This PDF file contains the front matter associated with SPIE Proceedings Volume 7821, including the Title Page, Copyright information, Table of Contents, Introduction and the Conference Committee listing.

Clock synchronization is a critical component in wireless sensor networks, as it provides a common time frame to different nodes. It supports functions such as fusing voice and video data from different sensor nodes, time-based channel sharing, and sleep wake-up scheduling, etc. Early studies on clock synchronization for wireless sensor networks mainly focus on protocol design. However, clock synchronization problem is inherently related to parameter estimation, and recently, studies of clock synchronization from the signal processing viewpoint started to emerge. In this article, a survey of latest advances on clock synchronization is provided by adopting a signal processing viewpoint. We demonstrate that many existing and intuitive clock synchronization protocols can be interpreted by common statistical signal processing methods. Furthermore, the use of advanced signal processing techniques for deriving optimal clock synchronization algorithms under challenging scenarios will be illustrated.

The discovery of the Fast Fourier transform (FFT) algorithm by Cooley and Tukey meant for diffraction computation what the invention of computers meant for computation in general. The computation time reduction is more significant for large input data, but generally FFT reduces the computation time with several orders of magnitude. This was the beginning of an entire revolution in optical signal processing and resulted in an abundance of fast algorithms for diffraction computation in a variety of situations. The property that allowed the creation of these fast algorithms is that, as it turns out, most diffraction formulae contain at their core one or more Fourier transforms which may be rapidly calculated using the FFT. The key in discovering a new fast algorithm is to reformulate the diffraction formulae so that to identify and isolate the Fourier transforms it contains. In this way, the fast scaled transformation, the fast Fresnel transformation and the fast Rayleigh-Sommerfeld transform were designed. Remarkable improvements were the generalization of the DFT to scaled DFT which allowed freedom to choose the dimensions of the output window for the Fraunhofer-Fourier and Fresnel diffraction, the mathematical concept of linearized convolution which thwarts the circular character of the discrete Fourier transform and allows the use of the FFT, and last but not least the linearized discrete scaled convolution, a new concept of which we claim priority.

The application of coherence proprieties of bimodal field in quantum lithography and quantum holography is proposed. The coherence effect between the photons from Stokes and anti-Stokes waves generated in Raman lasing emission is established. The application of Stokes and anti-Stokes bimodal coherent field in lithography and holography are given in according with the definition of amplitude and phase of such entangled states of light. The optical scheme of holographic representation of object in bimodal representation is proposed.

The deployment of Wireless Sensors Network for Structure Health Monitoring will allow better maintenance of the aircraft and predictive diagnosis of the aircrafts in a long term approach. This paper presents our research on the design of wireless communicating nano-objects for Structure Health Monitoring in the aircrafts and the improvements bring by the nanotechnologies. The main challenges we address here are the design of ultra low power communicating circuits to enable high lifetime for the communicating nodes and their integration on flexible substrate to allow their deployment in difficult accessible places on the aircraft using conventional technologies. Other main issues are the choice of the communicating frequency which will allow a high number of communicating nodes in such a small area like the cabin of an aircraft and the choice of the network architecture.

Femtosecond filamentation of 800 nm laser pulses in the conditions of strong two-photon absorption was first directly observed in As₄Ge₃₀S₆₆ chalcogenide glass. In this paper we also present the experimental results on laser self-written waveguides in arsenic-germanium-sulfide glasses. In contrast, there was no filamentation and spectrum widening in stoichiometric As₂S₃ glass. It was shown that nonlinear figure of merit was as high as 0.52 and only 0.04 in glassy As₄Ge₃₀S₆₆ and As₂S₃, respectively.

We present the results of computer simulation of spatial distribution of the Poynting vector and illustrate motion of microparticles in spatially inhomogeneously polarized fields. The influence of phase relations and the degree of mutual coherence of superposing waves in the arrangements of two-wave and four-wave superposition on the characteristics of microparicle's motion has been analyzed. The prognosis of prospects of the study of temporal coherence using the proposed approach is made.

Spectral system (acronym SPECTECH) is designed to meet the following basics: a) to assure measuring tiny optical single lens in a standard configuration; b) configured for reflected or transmitted beam light; c) configured by user off line to monitor manufacturing or mounting optical components; d) to be flexible to be equipped with more than one spectral detector. Initially, it is equipped with two spectral detectors, but in short time to be able to use more than two. e) configured as process spectrophotometer (continuously) to monitor manufacturing or mounting optical components; f) to be updated or upgraded to meet other necessities. SPECTECH system is a modular one, allowing spectral determinations in a wide range of spectrum (385-1100 nm) and with two detectors UV-VIS (190-1100) and NIR (1000-1700nm) the domain can be wider, covering spectrum from 190 to 1700 nm. Keywords: spectral signal, spectrometry.

The optical properties of amorphous Ge_xAs_xSe_2-x (x=0.05÷0.30) thin films prepared by thermal evaporation on the glass substrates held at T_substr=100°C are reported. The transmission spectra was used for calculation of the absorption coefficient α, optical band gap E_g, and the values of the refractive index n. The dependences of α, E_g, and n on the film composition in the Ge_xAs_xSe_2-x glassy system were determined. It was established that the optical band gap E_g decreases, while the refractive index n increases with the increasing of the concentration of Ge and As in the Ge_xAs_xSe_2-x glassy system. The time dependence of the transmission T(t) during the light exposure for the above band gap illumination (photodarkening) is described by a strength exponential behaviour T(t)/T(0) = A₀+Aexp[-(t-t₀)/τ]^(1-β), where t is the exposure time, τ is the apparent time constant, A characterizes the exponent amplitude, t₀ and A₀ are the initial coordinates, and β is the dispersion parameter (0<β<1).

Two different designs of 2D photonic crystal lattices that exhibit large complete photonic band gaps have been recently proposed [1] : (1) honey-comb lattice with two different hole radii; (2) "tri-ellipse" pattern in a triangular lattice. We perform a full 3D analysis of guided and leaky modes in vertically symmetric slabs based on these lattices. Guided modes are obtained through the plane-wave expansion method (PWEM) with a vertical supercell. Leaky modes are obtained through a finite difference time domain (FDTD) analysis with a combination of Bloch and perfectly matched layers boundary conditions. The analysis is carried out for both even and odd modes with respect to the plane bisecting the slab. It turns out that the classical 2D effective index method predicts a false bandgap in odd modes for high-indexcontrast photonic crystal slabs studied here.

It is well-known that hydroxyapatite have multiple applications in tissue engineering due to compositional similarities with bone tissue. In this work, hydroxyapatite powders obtained by modified chemical precipitation route, has been investigated by AMF and SEM analysis grain size, X-ray diffraction and infra-red spectroscopy. The particle size of hydroxyapatite was observed to be very fine, uniform, around 50 -60 nm. SEM observation of the HA coatings showed the presence of nano-sized needles, with a significant level of agglomeration. The infrared analysis show the characteristic peaks of absorbed water, hydroxyl, phosphate and carbonate species. The XRD pattern clearly indicated the crystallites responsible for the Bragg reflection of the (002) and (003) planes are useful for size determination by Sherrer relationship (around 68 nm).

After many experimental investigations of passive harmonic mode-locking erbium doped fiber ring laser cavity, we have observed some new typical characteristics of the solitons and we propose here a circular cavity laser where a high frequency cavity transmission modulation is possible by sending a reflected pulse into the cavity, in the opposite direction to the direct pulse. The pre-saturation of the absorber and the gain depletion at the optimum frequency, superposed on the natural effect of harmonic state, determine a stable harmonic solitonic state. In this mode we can better estimate the importance of the role of unstable continuous waves and of gain recovery in forming a stable equidistant multisoliton state.

Passively Mode-Locked Fiber Lasers (PMFL) performances strongly depend on the type and position of the elements used in the cavity. We report, based on various experimental attempts to improve the performances of PMFL, an increase of up to seven times of the sol tonic stability if a length of dispersion compensating fiber (DCF) is introduced between the amplifier and the saturable absorber. This area of the cavity is very important, as found when using the same length of DCF in other positions. We also observe that the performances of the laser are improved; for the same pumping power the spectral width of the sol tonic pulse grows and its duration decreases sensitively. The optimum length of the DCF depends on cavity properties such as total length, cavity gain, and attenuation.

Scientific research of surface acoustic wave (SAW) devices had an early start by the end of 1960s and led to the development of high frequency and small size piezo devices. A sustained effort was dedicated for these components to be transformed into many more interesting applications for telecom market. Recently the employment of new piezo materials and crystallographic orientations open new opportunities for SAW filters. New piezoelectric crystals of gallium orthophosphate (GaPO₄) provide higher electromechanical coupling than quartz, while maintaining temperature compensated characteristics similar to quartz. Based on this material phase transition of 970°C, development of new piezo devices to operate at higher temperatures up to 800°C can be done. SAW velocities about 30% lower than ST-X quartz, favors smaller and more compact devices. Other advantages of GaPO₄ are: stability with high resistance to stress induced twinning, 3~4 times higher electromechanical coupling than quartz and existence of SAW temperature compensated orientations. Another family of new materials of the trigonal 32 class has received much attention recently because of their temperature behavior similar to quartz and the promise of higher electromechanical coupling coefficients. It is the family of langasite (LGS, La₃Ga₅SiO₁₄), langatate (LGT, La₃Ga_5.5Ta_0.5O₁₄) and langanite (La₃Ga₅.5Nb_0.5O₁₄). Langasite crystals, easier to obtain and with the value of electromechanical coupling coefficient intermediate between quartz and lithium tantalate (k²=0.32% for 0°, 140°, 22.5° orientation and k²=0.38% for 0°, 140°, 25° orientation), enable us to design SAW filters with a relative pass band of 0.3% to 0.85%. Other piezoelectric materials are reviewed for comparison.

Over the years extensive studies have been carried out to apply coherent optics methods in real-time processing, communications and transmission image. This is especially true when a large amount of information needs to be processed, e.g., in high-resolution imaging. The recent progress in data-processing networks and communication systems has considerably increased the capacity of information exchange. We describe the results of literature investigation research of processing methods for the signals of the three-dimensional images. All commercially available 3D technologies today are based on stereoscopic viewing. 3D technology was once the exclusive domain of skilled computer-graphics developers with high-end machines and software. The images capture from the advanced 3D digital camera can be displayed onto screen of the 3D digital viewer with/ without special glasses. For this is needed considerable processing power and memory to create and render the complex mix of colors, textures, and virtual lighting and perspective necessary to make figures appear three-dimensional. Also, using a standard digital camera and a technique called phase-shift interferometry we can capture "digital holograms." These are holograms that can be stored on computer and transmitted over conventional networks. We present some research methods to process "digital holograms" for the Internet transmission and results.

The pulsed laser ablation of aluminium, copper and titanium irradiated with 4.5 ns pulses at 355 nm, 532 nm and 1064 nm wavelengths is investigated in open air at normal atmospheric conditions. The effect of pulse number, which is varied in the range of 5 to 50, on ablation rate in these three wavelength regimes is determined. The results indicate a higher efficiency of the ablation in VIS and UV regimes as compared to IR regime which is characterised by a very small optical absorbtivity. The ablation rate is demonstrated to be approximately constant when increasing the pulse number up to a certain value which strongly depends on the thermal properties of the material. Further increase of pulse number leads to a progressive decrease of ablation rate. The most pronounced decrease was obtained at 355 nm in aluminium where the ablation rate corresponding to the 50^th pulse is about 20% of the ablation rate corresponding to of first pulse. The decay of the ablation rate with the pulse number is attributed to the superposition of two phenomena: the enhanced attenuation of the laser beam in the plasma plume which is confined within the crater, and the decay of the effective laser fluence at the target surface due to the gradual increment of the effective irradiated area with pulse number.

LTCC (Low Temperature Co-Fired Ceramic) has great potential in the field of sensors and transducers due to its thermal, electrical and mechanical properties. The paper describes work concerning a capacitive pressure sensor realized on LTCC with thick-film deposition technologies. A capacitive pressure sensor converts a change in the position of the conductive plates to an electrical signal; for this a deformable diaphragm is used. In the presented case one electrode is bonded to the deformable diaphragm (an edge-clamped, circular diaphragm) and the other electrode is fixed. The signal from the sensor is processed by the AD7745 circuit. This circuit is a high resolution digital capacity-signal converter with high performances, high linearity ±0.01% and very good accuracy ±4 fF. The circuit also encompasses a voltage reference and a temperature sensor with a resolution of 0.1°C. The external connection is made through the I2C interface, using a signal control unit which processes the signal and sends the information to an LCD (liquid crystal display) and/or to a computer which, in turn, records the information for later use through the USB interface.

Based on the transmission experimental spectra of Er³⁺ -doped Ti:LiNbO₃ optical waveguides in this paper we report some experimental and theoretical results concerning the evaluation of the the radiative lifetime and the real and imaginary parts of the complex atomic susceptibility of the above mentioned waveguides in the visible and near infrared spectral range. The homogeneous absorption and emission cross sections were determined from the the corresponding experimental transmission spectra around 1550 nm, 980 nm and 550 nm using the density matrix formalism and the McCumber's theory and taking into account the Stark splitting of the levels.

Nanomedicine is defined as the monitoring, repair, construction, and control of human biological systems at the molecular level using engineered nanodevices and nanostructures. Polyacrylonitrile (PAN) solution containing the iron oxide precursor iron (III) was electrospun and thermally treated to produce electrically conducting, magnetic carbon nanofiber mats with hierarchical pore structures. This paper discusses the synthesis of magnetite (Fe₃O₄) nanoparticles with mean crystallite size of 10 nm with polyacrylonitrile (PAN) as the protecting agent, creating nanofiber. The morphology and material properties of the resulting multifunctional nanofiber including the surface area were examined using various characterization techniques. Optical microscopy images show that uniform fibers were produced with a fiber diameter of ~600 nm, and this uniform fiber morphology is maintained after graphitization with a fiber diameter of ~330 nm. X-ray diffraction (XRD) studies reveal the size of Fe₃O₄ crystals. A combination of XRD and electron microscopy experiments reveals the formation of pores with graphitic nanoparticles in the walls as well as the formation of magnetite nanoparticles distributed throughout the fibers.

Tin chalcogenides SnX₂ and SnX, where X = S, Se and Te present a particularly interest for their electronic properties and applications in gas sensors. The state of tin in these materials is important for understanding of the sensing effect and improvement of the sensor performances. Mössbauer spectroscopy is a widely used technique for the analysis of the local electronic structure or chemical bonding in solids. In this paper we applied Mössbauer technique for the investigation of bulk and thin films of SnSe₂ chalcogenide. The films of SnSe₂ chalcogenide were obtained by the methods: PLD ("Pulsed laser deposition") and PED ("Pulsed electron deposition"). Mössbauer measurements were performed by transmission (TMS), respectively conversion electron spectroscopy (CEMS). By CEMS spectroscopy surfaces, coatings and thin films containing Sn can be studied on substrates and to various depths up to 1000 nanometers.

The action of detergents is thought to be connected primarily with micelle formation. However, detergent monomers can also affect biological systems. It was found that human red blood cells can be disintegrated with Triton X-100 non-ionic detergent at a concentration of 0.007%, lower than the critical micellar concentration (CMC). The lytic membrane of non-ionic detergent Triton X-100 (as a model), and its ability to lyse red blood cells in vitro used as an indicator of conjugate conformation at different pHs. The time dependent release of hemoglobin (Hb) and potassium from red blood cells was detected at 37 °C and both were sigmoid in character. Although Triton X-100 was highly lytic at pH 5.5, 7.4 and 8.0, the conjugate only show a lysis concentration-dependent of red blood cell at pH 5.5. Triton X-100 causes the Hb to aggregate, a condition that can be simulated when this non-ionic surfactant is incubated with Hb in vitro. The determination of Triton-X was done by HPLC, in accordance to characterize the surfactant. The increased stability in micellar medium can be attributed to deep penetration with the polar group -OH oriented towarded to the micelle surface. Thermal stability of hemoglobin has been investigated in order to evaluate the nature of thermal behavior of this compound. We studied the effects of surfactant Triton -X on the rate constants for the destroying of hemoglobin.

In this paper, the study of obtaining new coordination compounds of Ni (II) and Co(II) using as ligand, N-hydroxy-succinimide, was presented. Also, the stability constants of these compounds in aqueous medium were determined. The obtaining conditions and the stability of the new compounds were accomplished in aqueous solutions using characteristic methods for coordination compounds: pH-metry, conductometry and UV-VIS absorption spectroscopy. The combination ratios and the stability constants were determined with methods characteristic for studies in solutions. From experimental data resulted that the combination ratio of central metallic atoms with the ligand N-hydroxy-succinimide was: 1:1 and respectively 1:2. In the experiments were used salts of NiCl₂·6H₂O and CoCl₂·6H₂O. The optimal domain of pH stability of the studied compounds is limited between 5.74 - 5.86 for Co- N-hydroxy-succinimide (for molar ratio 1:1 and 1:2) and respectively 5.69 - 5.87 for Ni-N-hydroxysuccinimide( for molar ratio 1:1 and 1:2, too). It is important to mention that these compounds were used with very good results in determination of wastewaters from textile, metallurgical, chemical and food industry. Complexion reactions with this ligand are very sensitive for the cations in this paper mentioned. Therefore it is used most often with success in analytical chemistry and also it is posibil to use as sensors. The new complex compounds has electronics transitions at λ = 517 nm for both complexes Co-N-hydroxy-succinimide at molar ratio 1:1 and 1:2 and also at the same λ = 397nm for Ni-N-hydroxysuccinimide at molar ratio 1:1 and 1:2. These complexes compounds was separated and recrystallized from aqueous solution. From the spectrophotometric data it was determined the type and the nature of the electronics transitions by Dq parameters.

The aim of this paper is to present two different types of MEMS switch structures developed in IMT: bridge and cantilever. For these two configurations were chosen different length of bridges and cantilevers; also, for the actuation pads used were considered different size. Finite Element Method simulations were performed in order to determine the pull-in voltage. Comparison between simulated and measured results will be presented for the bridge type switch structure.

The aim of this work was to develop a new MEMS switch structure for millimeter wave applications, which can be integrated with other more complex devices for developing of reconfigurable filters or antennae for microwave or millimeter wave frequency range. Electrostatic force was chosen for the switching operation, which seams to be the only way to obtain high reliable and wafer scale manufacturing techniques at these frequencies. Different geometries of the switching element were designed and manufactured in order to study the mechanical stability of these structures; the measured actuation voltage, of about 24,5V, shows an acceptable value for the further applications. Measured and simulated results of these structures (insertion losses of about 0.75dB@60GHz and isolation >50dB@60GHz) were in good agreement and are promising for further applications in this frequency range.

The objectives of this study are to survey the literature regarding energy evaluation and find optimal solution based on models and experimental set-up's for small and medium home in Alba area. Wind resource evaluation is a critical element in projecting turbine performance at a given site. The energy available in a wind stream is proportional to the cube of its speed, which means that doubling the wind speed increases the available energy by a factor of eight. Furthermore, the wind resource itself is seldom a steady, consistent flow. It varies with the time of day, season, height above ground, and type of terrain. Proper siting in windy locations, away from large obstructions, enhances a wind turbine's performance. We used our measured data in 2 locations around our town and with this data inserted in some Matlab models we intend to build optimal experimental solution for produced home's generator's, around Alba town, up to 5 kW.

In this paper we report some experimental and theoretical results concerning the characterization of the Er ³⁺ :Ti:LiNbO₃ and Ti:LiNbO₃ optical waveguides using the near-field measurements at 1540 nm wavelength. The near-field measurements have been performed using a standard fibre probe for the scanning of the waveguide transversal section, but also an infrared vidicon camera. Using the Helmholtz scalar equation and a deconvolution procedure we evaluated some parameters which characterize Er ³⁺ :Ti:LiNbO₃ waveguides: the refractive-index difference and the penetration depth. Also, we evaluated the coupling loss coefficients between a standard optical fibre and Ti:LiNbO₃ and Er ³⁺ :Ti:LiNbO₃ optical waveguides for λ =1.54 μm.

This work tries to optimize the conditions for chemical synthesis of nanosized magnetic iron oxide powders with desired biological properties. It was obtained iron oxides by sonochemical method, favoring the synthesis at low-temperature, low costs, high material purity and nanostructure control. For biomedical applications like magnetic biofunctional material vectors to target tissues, the iron oxide particles obtained have to be spherical with 10 nm average diameter. The influences of Fe ions concentration on the shape, size and size distribution of the obtained nanoparticles it is important for synthesis of nanoparticles used in medical application because it is necessary to have small size distribution and similar shapes. The paper it compares the size variation for five different concentrations. Some investigation techniques as: Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD), termogravimetric analysis (TGA), magnetization analysis, has been used.

With the globalization of the markets and the growth of competitiveness in the manufacturing sector, quality has become a key factor of success. Quality is particularly important for the companies which activate in the micro(electronics) field. The quality management system holds a vital place in the company's structure. Implementing such a system requires important operating costs. These costs are known as Quality Obtaining Costs (QOC) and may be considered as an investment. Planning an investment, means evaluating its return in order to see if it is profitable or not. Measuring the return of quality politics investment raise some delicate problems. We may calculate some aspects of the return of investment by measuring the shape of non-quality costs. An eventual decrease of these costs could be synonym with a profitable investment. But the advantages of good quality politics cannot be measured only by taking into consideration the non-quality costs (even if they include direct and indirect costs). There are also intangible advantages (like mark image, competences, polyvalence, client's satisfaction...) that derive from quality approaches. How to evaluate this type of consequences / advantages? The idea developed in this article is to considerate the quality politics like un immaterial/intelligent investment. Therefore could it be advantageous / possible to use the immaterial investment's measuring and evaluation techniques for studying the quality politics return of investment?

The use of the method of field polarization modulation for defining the degree of coherence of circularly polarized waves is offered. The role of the reference circularly polarized wave in transforming the spatial distribution of polarization into the depth of visibility modulation of the resulting distribution which can be metrologically estimated and analyzed is demonstrated.

The rapid diffusion of wireless communication systems has caused an increased concern for the potential detrimental effects on human health deriving from exposure to electromagnetic field. It penetrates the body and acts on all the organs, altering the cell membrane potential and the distribution of ions and dipoles. The thyroid gland is one of the most exposed vital organs and may be a target for electromagnetic radiation. This paper presents the computed temperature and specific absorption rate inside to a generic model of a human thyroid using signals radiated by an antenna operating in the 2450 MHz band and the power density levels up to 100 W/cm². Calculations were carried out using the Finite Difference Time Domain method for the solving of two coupled differential equations, Maxwell and Pennes. The results show that the temperature can rise up to very dangerous levels, i.e., 46 °C, in a very short time. The estimated temperature distribution in the human thyroid due to exposure from microwave signals can be used to design the dangerous aria for personal working around high power emitted antenna and for medical applications.

This work is directed to the investigation of the scope of the technique of laser polarimetry and polarization spectrometry of oncological changes of the human prostate tissue under the conditions of multiple scattering. It was shown that the third statistic moment in the intensity distribution proved to be the most sensitive to pathological changes in orientation structure. Its value in the intensity distribution of polarization image I (0 - 90) of oncologically changed tissue is 21 times higher if compared with the similar statistic parameter of the intensity distribution of the healthy tissue. The results of studies of size linear dichroism prostate gland, as healthy and affected by malignant tumor at different stages of its development was presented. Significant difference in the values of linear dichroism and its spectral dependence in the spectral range λ = 280 - 840 nm as between research facilities, and between biotissues - healthy (or affected by benign tumors) and cancer patients was shown. These results may have diagnostic value for detection and assessment of the development of cancer.

The qualities of the polarization-correlation structure of the images of thin film of amino acid are researched. The samples of 20 amino acid were used in the experiment on the modified micropolarimeter. Research methods are Mueller matrices polarimetry and spectropolarimetry in 200-2000 nm, as well as spectrometry in 2500-25 000 nm. The two-dimensional distribution of Stocks image and Mueller matrix elements of amino acid are obtained, the correlated analysis of the necessary images was carried out. The specific for every amino acids uniaxial character of the crystals was corroborated.

The goal of this paper is to simulate the conversion from light to numerical signal which occurs during the image propagations through the digital camera pipeline. We focus on the spectral and resolution analysis of the optical system, the Bayer sampling, the photon shot and fixed pattern noise, the high dynamic range image, the amplitude and bilateral filters and the analog to digital conversion. The image capture system consists of a flash illumination source, a Cooke triplet photographic objective and a passive pixel CMOS sensor. We use a spectral image in order to simulate the illumination and the propagation of the light through the optical system components. The Fourier optics is used to compute the point spread function specific to each optical component. We consider the image acquisition system to be linear shift invariant and axial. The light propagation is orthogonal to the system.

The human eyes' visual system interprets the information from the visible light in order to build a representation of the world surrounding the body. It derives color by comparing the responses to light from the three types of photoreceptor cones in the eyes. These long medium and short cones are sensitive to blue, green and red portions of the visible spectrum. We simulate the color vision for the normal eyes. We see the effects of the dyes, filters, glasses and windows on color perception when the test image is illuminated with the D65 light sources. In addition to colors' perception, the human eyes can suffer from diseases and disorders. The eye can be seen as an optical instrument which has its own eye print. We present aspects of some nowadays methods and technologies which can capture and correct the human eyes' wavefront aberrations. We focus our attention to Siedel aberrations formula, Zenike polynomials, Shack-Hartmann Sensor, LASIK, interferograms fringes aberrations and Talbot effect.

Performed in this work are complex statistical, fractal and singular analyses of phase properties inherent to birefringence networks of protein crystals consisting of optically-thin layers prepared from blood plasma. Within the framework of a statistical approach, the authors have investigated values and ranges for changes of statistical moments of the 1-st to 4-th orders that characterize coordinate distributions for phase shifts between orthogonal components of amplitudes inherent to laser radiation transformed by blood plasma with various pathologies. In the framework of the fractal approach, determined are dimensionalities of self-similar coordinate phase distributions as well as features of transformation of logarithmic dependences for power spectra of these distributions for various types of human pathologies.

This paper follows to combine optical and biochemical techniques for identification the cell membrane transformation in the dynamic of growth and development of experimental solid tumour. It is researched that in all the cases the linear dichroism appears in biotissues (the human esophagus, the muscle tissue of rats, prostate tissue) with the cancer disease the magnitude of which depends on the type of the tissue and on the time of the cancer process development. As the linear dichroism is lacking for healthy tissues, then the obtained results can have diagnostic values with the purpose of detection and estimation of the stage of the cancer disease development.

The possibilities of local wavelet analysis of phase inhomogeneous laser images of human blood plasma have been considered in this work. It has been defined the set of statistic, correlation and fractal parameters of wavelet coefficient distributions, which characterize the different scales of polarization maps of blood plasma. Also, the discrimination criteria of the birefringence transformation processes of blood plasma anisotropic structures on different geometric scales have been estimated.

Computer generated holograms are designed starting with the images of the desired objects, which will be formed on a screen, after laser diffraction on the holograms. In the design step, these digitized images are placed inside the signal window. We analyzed the influence of the size and the position of the signal window on the parameters values of the diffracted intensity distribution (diffraction efficiency and uniformity). First, we considered simple objects (three points and a line with a given size) and then an object of a logo type. The distance between the hologram plane and the image plane was also preset. Simulation and experimental results are presented.

We investigated the recording-erase processes of a hologram in photochromic glass using a continuum Nd:YVO₄ laser radiation (λ=532nm). Its dynamic was evaluated in the reconstruction step. A bidimensional micrograting pattern was formed and visualized in photochromic glass. In the reconstruction step, we monitored the time decay of the diffraction efficiencyin plane oh the reconstructed object image. It gave information about the processes induced inside the material. Recording and reconstruction processes were done in an off-axis setup, and the movies of the reconstructed object images were recorded on a CCD camera. Measurements from the reconstruction kinetic, gave us information used to computing the variation of the refractive index of the photochromic glass during these processes.

Ellipsometry is a convenient means to ascertain electro-optic properties, and the null-type methods are particularly so because they do not require a powermeter. Electro-optic materials like Strontium Barium Niobate (SBN) with the symmetry axis normal or parallel to the surface are materials suitable for thin film integrated optic devices, therefore of practical interest. For this reason we endeavoured to devise and to test experimental arrangements that measure the birefringence of uniaxial structures with the symmetry axis parallel and perpendicular to the surface.

The GEANT4 package programs were used to calculate the contribution of external γ dose due to natural radioactivity of building materials. The method correlates the activity concentrations of 40K and members of the 238U and 232Th radioactive decay chains in building materials used for constructing the walls with the γ dose absorbed by a water phantom at the center of the room. The obtained results are in agreement with values measured and calculated by other authors.

Digital video transmission is a permanent subject of development, research and improvement. This field of research has an exponentially growing market in civil, surveillance, security and military aplications. A lot of solutions: FPGA, ASIC, DSP have been used for this purpose. The paper presents the implementation of an encrypted, IP based, video communication system having a competitive performance/cost ratio .

The GEANT4 package programs were used to calculate the contribution of external γ dose due to natural radioactivity of soils. The method correlates the activity concentrations of ⁴⁰K and members of the ²³⁸U and ²³²Th radioactive decay chains in soil with the γ dose absorbed by a water phantom. The obtained results are in agreement with values measured and calculated by other authors.

In this paper, the authors present a comparison between two types of photonic logical circuits. Both of them there are based not only interference but also birefringence phenomena. The main device is the double-slit interferometer. In first version of circuit the output of logical gate is in the place where the central maximum interference is. We consider that there is signal to the output of logical gate only when the interference phenomenon appears. In second version of circuit the output of logical gate is in the place where the first minimum interference is. We consider that there is signal to the output of logical gate only when the interference phenomenon doesn't appear. Both types of circuits can be implemented not only in the integrated optics but also in the classic optics (where the laser beam is propagated through air). There are immune to electromagnetic fields and to any type of radiation. The light signal remains all the time into optical domain in both versions of photonic circuits. They are fast. The speed of the information transfer is limited only by the speed of light through the respective medium.

In this paper, the authors present from theoretical point of view a comparison between two types of photonic logical circuits based on nonlinear optics phenomena. The linearly polarized light after two orthogonal directions is used for information processing by both types of photonic logical circuits. In first type of circuit at the each logical gate the input signals are amplified to a certain power value. In second type of circuit we assume that the power of signals can not be smaller than approximately 55% of the biggest signal power. This second type of circuit can be used in the circuits where it is well to know the losses, where the signal don't propagate on very long distances, in other words they can be used in good quality circuits where it is sure that the power of any signals can not be smaller than approximately 55% of biggest power of signal. The advantages of photonic logical circuits presented there are: the output signal is amplified to a certain value of power, they have a strong decidability, there are fast (switching time of photonic devices is about 10^-12- 10^-14s), the light signal remains all the time into optical domain etc.

The cooperative nonlinear scattering processes between two resonator modes stimulated by the excited atomic beam, it is studied. It is demonstrated that these collective scattering phenomena between the Stokes and Anti-Stokes resonator modes take place due to energy transfer between these fields. The quantum proprieties of Stokes and Anti- Stokes fluctuations of the photon numbers have been found. The correlation functions between these fields are expressed through the lasing parameters of the cavity. The experimental scheme of realization of such collective amplification of Stokes (Anti-Stokes) of photon number is proposed.

New light-emitting layers of nanocomposites on polymer base have been obtained. As polymeric matrices the copolymers of styrene and butilmetacrylate in the ratio (1:1) have been used. As organic luminophore compounds from izotiocianatopropenone and propenone classes were utilized. Transparent composite layers were deposited by spin-coating method on glass and quartz substrates. The morphological and optical properties of the obtained nanocomposites have been investigated. An intensive photoluminescence signal has been identified in green area of the spectrum. Nanocomposites are proposed for various practical applications.

The present research aims to investigate the effect of surface micro-topography on microchannel and microtube performance, both in terms of pressure drop and heat transfer. A test rig was conceived and built in order to study CPU thermal grease behavior when subjected to high temperatures, close to those leading to CPU failure. The rig allows the CPU to reach temperatures up to 110°C. A thin layer of thermal grease Keratherm Thermal Grease KP97 is applied on the CPU surface and then the temperature is gradually elevated. Once a stable thermal regime is established at a certain temperature level, the CPU surface covered in thermal grease is scanned by laser profilometry. Experimental results show a few interesting effects such as a significant volume growth leading to a "pump up" effect, roughness variations for different temperatures and roughness decrease when a crystal window is placed on thermal grease covered surface.

In recent years aluminum doped zinc oxide (AZO) film has attracted more attention due to many advantages including low cost, non-toxicity, and high stability to H2 plasma in comparison with indium tin oxide (ITO) film, the best known and used transparent conductive oxide (TCO) film. In this work, mono and multilayer Al-doped ZnO coatings have been obtained by dip coating sol-gel method on the glass and silicon supports. X-ray Diffraction, Atomic Force Microscopy (AFM) and Fluorescence Spectroscopy were used for the structural, morphological and optical characterization of the obtained coatings. The multilayer Al-doped ZnO coatings (after five layer depositions) on the silicon substrate present a polycrystalline wurtzite type structure with crystallite size of 20 nm. The AFM measurements have shown that no matter the support type, the Al-doped ZnO coatings present a similar morphology consisting in a smooth distribution of the circular grains leading also to similar values of the RMS roughness, around 2 nm. The photoluminescence properties of the Al-doped ZnO coatings depend on the number of depositions and type of substrate. Systematic study performed allows finding most suitable parameters for obtaining coatings with desired properties.

In this communication, the 3D heterogeneous integration of miniaturized communicating modules used for wireless network application is described. These communicating objects present the particularity of being in Nano-scale range. In fact, each object is composed of Nano-sensors, transceivers and E/R antenna. Such investigated ways of Nano-system integration will allow the development of sensor communicating modules which can be inserted and located in areas with access difficulty (in particular in non planar area) or even in inaccessible places. This attractive integration concept is discussed and illustrated here.

In the last decade, on the world wide it has been started to be applied the conservation of cultural heritage with nanomaterials. A deep investigation about the degradation mechanism of cultural heritage means the decisive step in the historical paper conservation. In particular, by using these compatible methods, it is possible to perform interventions without modification of the physicochemical and mechanical behavior of the materials, ensuring long-lasting effects. In this study alkaline nano-sized particles have been synthesized, as non-aqueous dispersions, because of their efficiency for the preservation of cellulose-based materials. The particles size and theirs size distribution have been measured by Dynamic Light Scattering (DLS) technique. The historical papers have been treated with the obtained nanoparticles and then the initial and treated book papers have been examined by Scanning Electron Microscopy (SEM).

Precise laser-dressing effects are considered for both the confinement potential of the coaxial cylindrical quantum well wires and the Coulomb potential of the impurities. The computation of the ground state subband energy eigenfunctions for different laser field parameters is based on the finite element method. Significant changes of the electron probability density under intense laser field are predicted. The binding energies of the shallow-donor impurities are variationally calculated within the effective-mass approximation. The study reveals that the laser field competes with the quantum confinement and breaks down the degeneracy of states for donors symmetrically positioned within the coaxial nanowires. A proper interpretation of the density of impurity states is considered to be essential for controlling the optoelectronic properties of doped semiconductor quantum well wires.

In this paper we present simulation of transmission / reflection spectra of polymeric rectangular and hexagonal photonic crystals (PC) as well as the propagation of radiation in a hexagonal PC - based waveguide. The polymeric PC are periodic structures consisting in square arrays of holes configured in suspended membranes of PMMA with different diameters and pitch (100 nm diameter with 500 nm, respectively 800 nm pitch; 200 nm diameter with 500 nm pitch; 400 nm diameter with 700 nm pitch). For fabrication, we propose the bi-layer EBL technique based on simultaneous patterning of a bottom sacrificial layer (LOR 5A - Microchem Corporation) and a positive electron resist (PMMA of different molecular weights). Characterization of nanostructures was performed using SEM imaging and AFM measurements .

The preservation of the cultural heritage is important for all countries, as this is a reminder of what they were once, being the most important element of identity in these modern days. The different directions and ways in which these processes are realized depend on the particular stage of development of science and technology, welfare of society, and encountered dangers of this identity. Very important objects of cultural heritage are material objects and objects of art produced by all communities. The study of nanostructured materials is considered an emerging field for the next years. To advance the field of preservation of cultural heritage science and nanostructured materials there is a continuous interdisciplinary collaboration between material science specialists and preservationists. In this work we present a complex study on the synthesis and the application of nanomaterials for the restoration and conservation of different artifacts.

The nanoengineering of various materials for biomedical application has became in the last decade one of the most important research areas, due to the continuous struggle to find new and more efficient instruments for the therapy of cancer and other diseases. Attempts to obtain functionalized derivatives of fullerene seek the synthesis of watersoluble materials, in order to investigate their effects in physiological conditions. International studies on the biological properties of fullerenes and their derivatives, are now targeted towards anti-tumor effects, pharmacology and their involvement in oxidative stress. Their toxicity, demonstrated both in vitro and in vivo is important for characterization and selection of applications. Phototoxicity of some molecules of fullerenes has been identified as future therapeutic tool. The present paper describes the synthesis, characterization and some biomedical applications of some nanomaterials based on fullerenes.

Nanomaterials as novel materials with nanometer sizes are involved in higher performance technology. On this context nanobiotechnology is able to create different nanostructures using living organisms.An attractive research area is the application of microorganisms to synthesize nanoparticles from different metals, one of which is silver, an antimicrobial agent. Green production methods have a considerable interest for environmental protection, often based on plant extracts, organic compounds or microorganisms (bacteria, fungi, algae). Marine plants were used as "real factors" for synthesis of nanoparticles of Au and Ag using different processes of biomineralization. This paper deals with a complete study about obtaining silver nanoparticles from AgNO₃ using red algae (Porphyridium purpureum). The red algae contain the red pigment-phycobilins, responsible for red color and for the strong absorption in visible spectrum. The properties and structure of silver nanoparticles have been put into evidence by means of: Fourier transform infrared spectroscopy-FTIR, optical microscopy, X-ray fluorescence spectrometry-EDXRF.

A numerical analysis of TE mode of electric field propagation through the interface between a thin film of TiO2 and periodic metal slits of silver is presented. The lossy metallic slits are optically described by Drude model. A grid of regular slits generates sharp hotspots of electric field at the exit plane. Adding a 2D rectangular photonic crystal made of air cylinders in titanium dioxide will enhance the electric field at the exit from the metallic slits without any loses in propagation distance and peak width. An optimization of geometrical parameters of metallic slits and photonic crystals is made for the propagation of a visible incident radiation with the wavelength of 650nm.

The main paper presents studies and research concerning the development of new open architectures for real-time control of a 5 degrees of freedom platform with 4 nano-manipulators, based on multiprocessor systems operating in a cooperation regime in order to achieve experiments in the 4 research domains: robotics, vibro-acustica, tribology, carbon nano tubes (CNTs ). In order to obtain this performance a positioning method with high precision at high speed is developed through reducing and compensating the induced dynamic vibrations by the system movement using the inverse dynamics method. The system's performance will allow the introduction of new functions without significant change to the hardware system. Through determining the optimal trajectory using a quadratic cost function for reducing tracking errors results increased motion speed and micro or nanometric positioning precision.

An exact analytical approach for studying the time evolution of equidistant system of radiators prepared in a superposition of states in interaction with single cavity mode it is proposed. This method gives us the possibility to find the analytical representation of wave function for a large system of atoms. Exact solution for interaction of four radiators with quantum cavity field is presented. The representation of cavity field is studied as function of the number of atoms in the system. For odd numbers of radiators was established the following role: one atom have one quantum Rabi frequency, three atoms have two frequencies; fife atoms- thee nonzero frequencies. The zero value Rabi frequencies in the system is absent. For even atomic numbers the zero value of Rabi frequencies appear: two, four, six and so one. In the last case the number of collective level in the system is odd and the trapping states of the atoms in the cavity are possible.

The skin is the largest organ of the body and it protects against heat, light, injury and infection. Skin temperature is an important parameter for diagnosing diseases. Thermal analysis is non-invasive, painless, and relatively inexpensive, showing a great potential research. Since the thyroid regulates metabolic rate it is intimately connected to body temperature, more than, any modification of its function generates a specific thermal image on the neck skin. The shapes of thermal signatures are often irregular in size and shape. Euclidean geometry is not able to evaluate their shape for different thyroid diseases, and fractal geometry is used in this paper. Different thyroid diseases generate different shapes, and their complexity are evaluated by specific mathematical approaches, fractal analysis, in order to the evaluate selfsimilarity and lacunarity. Two kinds of thyroid diseases, hyperthyroidism and papillary cancer are analyzed in this paper. The results are encouraging and show the ability to continue research for thermal signature to be used in early diagnosis of thyroid diseases.

The goal of this paper is to present the building of a quadrant sensor based on an ultra low power microcontroller. The application of this sensor is a solar tracker system, and we will optimize it by comparing fixed solar panel efficiency versus a solar panel equipped with a solar tracker, based on an energetic balance. The related quality of services is fulfilled by functions dedicated to time related coordinates correction. The main requirements in solar cells system optimization are related to lifetime, reliability, robustness and quality of services. The life expectancy of the system is improved by using a microcontroller- based implementation. Our solar tracker implementation is used for orienting systems like day light reflectors or photovoltaic cells toward the sun, with some major additional improved functions in respect with the amelioration of reliability and robustness. The implementation of solar tracker system is based on a microcontroller, two servo motors and four photo resistors that are used as two half bridges sensors.

The design of the control systems for sensor networks presents important challenges. One aspect regarding large sensor networks represents the processes of monitoring the evolution in time of any sensor from the network and finding every critical or faulty situation which can affect the stability and functionality of the entire distributed sensors network. All these faulty or critical situations from the system are called in this study"mission-critical". In this paper we present one method to detect a possible "mission-critical" situation in a complex, sensor-based distributed control system. In order to fulfill this goal we optimize the sampling rate of some sensors for common distributed network system parameters for easily finding the moments which can be critical for the entire system.

Present paper describes a long term monitoring process of few environmental parameters for evaluating green energy potential (wind energy and solar energy) of a small geographical area (~ 32 km²). The monitoring approach presented in this paper consists in: real-time data acquisition process using two real-time data acquisition devices (DAQ); a wireless network used for long distance data transmission in order to send all acquired data to a remote location for processing; Virtual Instrument (VI's) applications used for controlling data acquisition devices and the acquisition process; a network protocol analyzer used for a detailed analysis of the communication protocols and data packets; the management of the huge volume of sensor data by using a high level software application; long term sensor monitoring using a complex graphic software application. The measured environment parameters are the following: wind speed, wind direction, temperature, sun intensity and illumination, steel pylon vibrations on three axes.

Temperature and humidity sensors have a broad range of applications, from heating and ventilation of houses to controlled drying of fruits, vegetables or meat in food industry. Modern sensors are integrated devices, usually MEMS, factory-calibrated and with digital output of measured parameters. They can have power down modes for reduced energy consumption. Such an integrated device allows the implementation of a battery powered wireless sensor when coupled with a low power microcontroller and a radio subsystem. A radio sensor can work independently or together with others in a radio network. Presented paper focuses mainly on measurement and construction aspects of sensors for temperature and humidity designed and implemented by authors; network aspects (communication between two or more sensors) are not analyzed.

The paper presents the three most efficient methods of biometric identification: fingerprint recognition, face recognition and iris recognition. The authors evaluated the performance of each method, based on the concept of error rates. The paper also presents an overview of the biometric identification implementations, highlighting the advantages and disadvantages from a practical point of view, based on a balance between reliability and invasiveness of each method.

The designed and simulated system will be used in the tanning industry, for Volatile Organic Compound (VOC) measurements. In this industry, about 90% of the solvent contained in the emulsions evaporates during its application, giving rise to VOC, which are at the same time hazardous atmospheric pollutants and one of the sources of ground level photochemical ozone formation. It results that a monitoring system is necessary in a leather finishing process, in order to detect hazardous VOC concentration and conducting process in order of VOC concentration diminishing. The paper presents the design of a VOC monitoring system, which includes sensors for VOCs and temperature, the conditioning circuitry for these sensors, the suction system of the gas in the hood, the data acquisition and the computing system and graphic interface. The used sensor in the detection system is a semiconductor sensor, produced by Figaro Engineering Inc., characterized by a short response time, high sensitivity at almost all VOC substances. The design of the conditioning circuitry and data acquisition is done in order to compensate the sensor response variation with temperature and to maintain the low response time of the sensor. The temperature compensation is obtained by using a thermistor circuitry, and the compensation is done within the software design. A Mitsubishi PLC is used to receive the output signals of the circuits including the sensor and of the thermistor, respectively. The acquisition and computing system is done using Mitsubishi ALPHA 2 controller and a graphical terminal, GOT 1000.

LTCC (Low Temperature Co-Fired Ceramic) has great potential in the field of sensors and transducers due to its thermal, electrical and mechanical properties. The paper describes mainly work concerning a piezoresistive pressure sensor realized on LTCC with thick-film deposition technologies. The most important part of a piezoresistive pressure sensor is the membrane. A deflection appears when pressure is applied. Bonded to the membrane is a Wheatstone bridge - when the membrane is deformed a current imbalance follows [1]. The measurement system is realized as two independent functional blocks. The converting and interfacing block, situated close to the sensor is a specialized circuit, AD7730. This circuit contains an amplifier with variable casting, a delta-sigma converter, a digital programmable filter to eliminate errors and an internal calibration and I2C interface with the outer unit. The signal delivered by the sensor is processed and displayed by the microcontroller (in our case PIC16F73). The capacitance value is displayed on an LCD (liquid crystal display) with 2 lines and 16 columns. Another possibility is to connect the circuit to a PC for long term study and in order to allow complex operations and to build up graphs. We shall compare the circuit for this piezoresistive sensor with that for a capacitive pressure sensor realized on LTCC [2].

Despite the fact that today vehicles are easier to drive and more reliable, the drivers' carefulness is diverted by a large number of factors (road conditions, traffic conditions, phone calls, navigation systems etc.). The automatic system of controlling the windscreen wipers meets exactly one of the carelessness factors. A rain sensor makes the activation of the system of windscreen wipers to become something that you turn on and forget about it. This completely automated system activated by rain measures the rain intensity and also the necessity to turn on the windscreen wipers and with what velocity. Using an advanced optical system, analogue signal processing and a control algorithm, this technology offers more safety and comfort on different weather conditions. The sensor beams an infrared light on the windshield at an angle carefully chosen. If the windshield is dry, the beam is reflected back in the sensor. If on the glass there are rain drops, they will reflect the light in different directions (the wetter the windshield is, the least of the beam ray is reflected back in the sensor).

In this paperwork based on the adequate models it is analysed the operating conditions, and are established the noise main characteristic for MOS Hall plates. By using the numerical simulation the values of the signal-to-noise ratio and the noise-equivalent magnetic induction for different structure devices are compared and it is also emphasized the way in which choosing the geometry and the material features allows getting high-performance sensors.

The noise-signal at the output of a Hall magnetic sensor can be interpreted as a results of an equivalent magnetic induction, acting on a noiseless Hall device. In the paperwork is defined this characteristic for two Hall devices realised in the bipolar and the MOS integrated circuits technology. The influence of geometry and material properties on these essential parameters in the characterisation of magnetic sensors performances, can be emphasised by simulating a few Hall devices structures.

An essential parameter in the setting up of the performance of the measurement systems that uses Hall microsensors is the detection limit of such devices. The paper presents the results of research work regarding the analysis and optimization of magnetic microsensor structures realized in bipolar and MOS integrated circuits technology. On the basis of adequate models these have been established the noise main characteristics for double collector vertical magnetotransistor and for double-drain MOSFET magnetotransistors. By using the numerical simulation the values of the signal-to-noise ratio and the detection limits for the two analysed structured are compared and it is also emphasized the way in which choosing the geometry and the material features allow getting high-performance sensors.

Amanita is one of the most well known basidiomycetes genus throughout the world because some of its species that are acknowledged due to their toxic and/or hallucinogenic properties. Considering these properties in the last decades become more important for scientist to dignify exactly the chemical content of these mushroom species. Latter researches shown that A. phalloides contain two main groups of toxins: the amatoxins and the phallotoxins. As regards A. rubescens there are not so much studies referring to its biochemical "fingerprint". Two species (A. rubescens and A. phalloides) of Amanita genus were studied in order to determine the biochemical hall-mark at nanoscale for these basidiomycete's species. Parts as caps, gills, flesh and stem of these mushrooms were analyzed on quadrupole mass spectrometer engaged with a gas chromatograph (GC-qMS) using selective ion monitoring mode (SIM). The biochemical profiles of these species had shown the presence of compounds like fatty acid methyl esters (FAMEs), alkaloids, and volatile compounds (including alcohol compounds, carbonyl compounds, terpenes). The levels of biochemical compounds from these species were compared between the two types of species and also between young, mature and old samples for the same species as well as between the parts of mushroom. After this comparison were between the two species it was observed that in case of A. phalloides the alkaloid content were higher usually with almost 50 %. As regards presence of volatile compounds they have almost similar level in both mushroom species. Considering the levels of fatty acid methyl esters, their levels were higher with 30 - 40 % in case of A. rubescens.

Biomonitoring studies for estimation population health surveillance and exposure risk assessment of different chemical contaminants such as chlorinated compounds or polycyclic aromatic hydrocarbon (PAH) compounds has become an important task especially after the Stockholm Convention. If before the toxicological evaluation of humans were done using invasive methods like surgery or pricking, today many scientists tried to elaborate non-invasive analytical methods without disparage the final results. During the last years studies it was observed a relative higher pollution with organochlorine and polycyclic aromatic hydrocarbon compounds in surrounding regions of Dej, Transylvania. These past studies shown that pollution with chlorinated compounds as chlorinated solvents are attributed to the industrial activities from this region. The levels in soil and river water of these compounds were: ≈ 20 - 60 μg·kg^-1 and ≈ 15 - 45 μg·L^-1, respectively. In case of PAHs the following results were obtained for soil and river water: for two ring specie was between ≈ 26 - 35 μg·kg^-1 and ≈ 21 - 30 μg·L^-1, respectively; for three ring species was 15 - 35 μg·kg^-1 and ≈ 10 - 24 μg·L^-1, respectively; and in case of four ring species was between 10 - 20 μg·kg^-1 and ≈ 3 - 15 μg·L^-1, respectively. These results carry on concern regarding the bioaccumulation of these pollutants by humans through food web chain. In order to establish the uptake level of these compounds by humans, home grown animal hair as pig and cow were analyzed through SIM-GC-MS mode and ECD-FID-GC. The presence of chlorinated solvents detected in pig and cows hair were as follows: compounds from chloromethane family ≈ 5 - 10 ng·kg^-1 dry weight; compounds from chloroethane family ≈ 7 - 34 ng·kg^-1 dry weight for pig hair, and ≈ 12 - 17 ng·kg^-1 dry weight for compounds from chloromethane family and 14 - 48 ng·kg^-1 dry weight for cow hair. Difference between accumulation levels of PAH metabolites were observed also between cow and pig hair samples.

A self-referencing inteferometric method of wavefront sensing based on lateral shearing interferometry, able to measure the local slope of a wavefront is described. For this, a deformable mirror is used to manipulate the testing wavefront and a Murty plane-parallel plate interferometer to analyze this wavefront. We demonstrate the interferometer by measuring a series of different wavefront shapes using coherent light. The principle of operation is presented together with practical implementation and experimental results.

In case that a pattern recognition system is used for images recognition (in robot vision, handwritten recognition etc.), the system must have the capacity to identify an object indifferently of its size or position in the image. The problem of the invariance of recognition can be approached in some fundamental modes. One may apply the similarity criterion used in associative recall. The original pattern is replaced by a mathematical transform that assures some invariance (e.g. the value of two-dimensional Fourier transformation is translation invariant, the value of Mellin transformation is scale invariant). In a different approach the original pattern is represented through a set of features, each of them being coded indifferently of the position, orientation or position of the pattern. Generally speaking, it is easy to obtain invariance in relation with one transformation group, but is difficult to obtain simultaneous invariance at rotation, translation and scale. In this paper we analyze some methods to achieve invariant recognition of images, particularly for digit images. A great number of experiments are due and the conclusions are underplayed in the paper.

Developing robot technology has gained an increasing dynamics. Small unmanned ground vehicle - SUGV has gained a place in the robotics field. This paper describes the possibility of remote control of the SUGV using a fuzzy algorithm. This designed algorithm specifically for controlling of a semi-autonomous mobile robot for research, observation, and surveillance. The device can provide 360-degree panoramic images using an image system which includes a hyperboloid mirror and a CCD camera, designed for this specific purpose. Both components, fuzzy algorithm and image system were implemented, tested in the laboratory condition and outdoor on a mobile robot for research, observation, and surveillance.

A laser interferometer, a vision system, and 1-D precision translation stage are used to develop a high precision measuring station with a working range of 12 mm. The object inspected by the laser-and-vision system is moved using a linear translation stage (LUMINOS INDUSTRIES I1000 - 1-Axis Stage) so that the camera can take images of the feature points of the object at two (or more) different positions. Meanwhile, the displacement of the table is measured using a laser interferometer. Putting these two feature points successively in focus the distance between them can be evaluated and adding the displacement measured by the laser interferometer, the real distance between these two feature points is obtained. The developed 1-D laser-and-vision measuring system is used to measure the geometric size (pitch) of grating type linear encoders or industrial line scales. Software counts automatically the number of lines and the laser interferometer produces the corresponding length. For dial instruments the vision machine observes the coincidence of the moving needle with divisions representing (sub) units of length. The displacements measured by laser interferometer are compared with dial indicator and the measuring errors are observed.

The paper presents the results obtained by the authors in the field of the system cosimulation of optoelectronic sensors. The aim was to make investigations in the multidomain simulation of the optoelectronic components and devices using PSpice and MATLAB/Simulink environments. The conclusion of this study is that a co-simulation environment allows to simulate the whole system using accurate models for the electronic devices.

I propose a measurement technique for determining the thermally-induced wavelength drift associated with channel switching in tunable lasers. Using a tunable optical filter as frequency discriminator and a photodiode, the wavelength drift is electrically converted into a measurable voltage, while the laser is periodically switched between two channels. I account both for the filter nonlinearity and the laser output power variations during the measurement. I used this technique to evaluate the wavelength drift for a SG-DBR laser, but the method could be easily used for any other type of tunable lasers exploiting the plasma effect.

The number of radio frequency surface acoustic wave (SAW) filters produced presently exceeds 3 billion per year. The demand for high-frequency SAW filters for telecommunications and remote sensing, has led to extensive research, focusing on new SAW microdevices. SAW devices have shown compact structures, small size, low cost, high sensitivity and fast response. The need of miniaturized systems, with high sensitivity and low energy has motivated the need to integrate on the same substrate all the structure of SAW device and connecting electronic circuits. As a consequence, many types of methods of both constructive and operating characterization of SAW devices have been developed. This paper provides a short introduction regarding the developed level of SAW microdevices and describes the results of literature investigation research of optoelectronic techniques for constructive characterization of SAW microdevices. Further research will be done into the determination of SAW parameters such as the amplitude of surface wave, the velocity of wave propagation on the surface of the piezoelectric substrate. Substrates of quartz, lithium tantalite (LiTaO₃) and lithium niobate (LiNbO₃), are piezoelectric materials commonly used in manufacturing of SAW devices, but these materials are not compatible with the integrated circuit (IC) technology. Three optoelectronic measurement techniques are known for detection of surface acoustic waves: diffraction grating technique, the knife-edge technique, and the detection of ultrasonic vibrations using optical interferometry. The research work given in this paper concentrates on describing of optoelectronic techniques used for constructive characterization of SAW microdevices. Finally, we try to draw some conclusion where: optoelectronic techniques are predicted to be one of the fundamental measurement methods for measurement of future SAW microdevices.

Obtaining mathematical models, as close as possible to physical phenomena which are intended to be replicated or improved, help us in deciding how to optimize them. The introduction of computers in monitoring and controlling processes caused changes in technological systems. With support from the methods for identification of processes and from the power of numerical computing equipment, researchers and designers can shorten the period for development of applications in various fields by generating a solution as close as possible to reality, since the design stage [1]. The paper presents a hybrid solution of modeling / simulation of a hydrostatic transmission with mixed adjustment. For simulation and control of the examined process we have used two distinct environments, AMESim and LabVIEW. The proposed solution allows coupling of the system's model to the software control modules developed using virtual instrumentation. Simulation network of the analyzed system was "tuned" and validated by an actual model of the process. This paper highlights some aspects regarding energy and functional advantages of hydraulic transmissions based on adjustable volumetric machines existing in their primary and secondary sectors [2].

This paper extends prior analysis of self-collimation effect in two dimensional photonic crystal structure patterned with a triangular lattice having hexagonal holes [1]. The equifrequency contours analysis is performed in order to determine the self-collimation effect frequency range for this structure. The routing of two self-collimated Gaussian beams travelling through a hexagonal photonic crystal, on the same optical layer is demonstrated. Using the unique advantage of allowing selfcollimated beams to cross each other without coupling, one can devise structureless interconnects for photonic integrated circuits [2].

Development of vertical cavity surface emitting lasers (VCSEL) is currently experiencing exponential growth. The main problem in achieving these lasers is the Bragg reflector that requires a large number of layers pairs with high contrast to obtain a high reflectivity DBR. But by increasing the number of layers and with the increase of contrast crack formation occurs due to the lattice mismatch between the different nitride compounds while keeping a large Refractive index contrast. By introducing a layer of superllatice (AlN)n/(GaN)n as one layer in the DBR pairs reduces lattice mismatch between the layers. Modeling was done using the self-consistent eight-band kp Schrödinger-Poisson solver. The refractive indices of these SLs were finally estimated for the design of an optimized high reflective Bragg mirror at 450 nm.

Free Space Optics (FSO) refers to the transmission of modulated visible or infrared (IR) beams through the atmosphere to obtain broadband communications. As long as there is a clear line of sight between the source and the destination, and enough transmitter power, communication is theoretically possible. FSO uses lasers to transmit data through the air rather than guided through an optical fiber. FSO technology requires no government licensing and can be readily deployed within hours of the availability of line-of-sight access. Systems capacities, for the available systems, are in the range of 100 Mbps to 2.5 Gbps. There have been reported systems with data rates as high as 160 Gbps. FSO is far more secure than Radio Frequency or other wireless-based transmission technologies for several reasons: (1) laser beams cannot be detected with spectrum analyzers; (2) laser transmissions are optical and travel along a line of sight path that cannot be intercepted easily; (3) the laser beams generated by FSO systems are narrow and invisible, making them harder to find and even harder to intercept and crack. This paper contains a detailed comparative analysis between the traditional radio links and Free Space Optics links. We present the advantages and challenges of FSO, the availability, capacity and transmission related issues.

In this paper the results of the simulation for a bimorph actuated micromirror on silicon substrate are presented. The response of the micromirrors, consisting in the displacement along z axis was investigated in static and dynamic regimes using Coventor software taking into account the material parameters and geometry of the structure. The structure is made from two layers gold and silicon oxide. The gold layer of the structure is patterned in two parts, one actuating part and one reflecting part. Due to this patterning thermal conduction through the gold layer is interrupted and as a result the reflective surface curling is reduced, thus improving reflectivity. The simulations were carried out in order to obtain an optimized structure geometry. We optimized the actuating part geometry analyzing convection, radiation, von Misses stress, temperature and displacement. As a result we need an actuating part with almost constant temperature and von Misses stress and higher displacement. Also we made simulations in order to reduce the stress in the reflective surface.

UV laser beam interaction with painting layers in case of aged mock-ups was investigated and ablation and cleaning thresholds were estimated as a function of each layer and sub-layer composition. Ablation depth measurements as a function of incident laser intensities and subsequent irradiation pulse number was measured with white light interferometry (WLI) and profilometric methods, demonstrating a selectivity of the removal of painting layers from submicrometric domain to micrometric domain as a function of surface cleaning needs. The laser cleaning station was designed and developed after careful evaluation of the irradiation conditions proper to the removal of painting layers. A Q-switched Nd:Yag laser radiation is delivered to the artwork through a mirror system consisting in an articulated arm and a laser head. A complete control of the incident laser parameters was envisaged with the laser remote control interface. The system also comprises diagnosis and monitoring tools for the remote control of the cleaning operation. The prototype is controlled by an integrated interface based on a user-friendly software to perform the available operations (e.g. laser cleaning, LIBS, colorimetry, live color monitoring, multispectral analysis, database management). The user interface is also used to start the treatment of a new work, to review or continue a previously started work.

The present research aims to study the way heat transfer occurs within micro and nano channels of a micro-heat exchanger. Several such heat exchangers were manufactured and a test rig was conceived and built in order to test them. For the experimental investigations, a method to test copper micro-tubes reaching 40μm in depth and 0.35 mm in width was advanced. The shape and dimensions of these micro-tubes were measured using laser profilometry. Experimental results showed different behavior for micro-heat exchangers, revealing a great importance of flow conduits configuration and the chosen path for working fluids.

Classification of sensory data is a major research problem in wireless sensor networks and it can be widely used in reducing the data transmission in wireless sensor networks effectively and also in process monitoring. In order to examine the huge size of data set in stream model generated by sensor network, it will be analyzed different sensor's output signal, topology of sensors network, number of sensor parameters and number of acquisition data. In our wind energy monitoring, sensor node monitors six attributes: speed, direction, temperature, pressure, humidity, and battery voltage. Every attribute value is set as four measures: average, instantaneous, minimum, and maximum. This paper presents several data mining techniques applied on the wireless sensor network's data considered: Naïve Bayes, k-nearest neighbor, decision trees, IF-THEN rules, and neural networks. Before classification, the data was clustered in order to be labeled. A similarity based algorithm, k-means, was selected in the clustering process for its simplicity and efficiency. A conclusion that decision trees are a suitable method to classify the large amount of data considered is made finally according to the mining result and its reasonable explanation.

Some pophyrins as molecular materials are discussed in this paper. Aggregates of these molecules have been known for some time to possess interesting properties. Their optical properties as isolated species in condensed phases have also recently become interesting, and their ability to form new hybrid materials, by mixing them with themselves or other molecules with different electron affinities and ionization potentials, now appears to be extremely attractive. Few porphyrin structures, 5,10,15,20-tetra-p-phenyl-porphyrin (TPP), 5,10,15,20-tetra-p-methoxy-phenyl-porphyrin (TMOPP), 5,10,15,20-tetra-p-tolyl-porphyrin (TTP), 5,10,15,20-tetra-p-sulphonato-phenyl-porphyrin (TSPP), have been synthesized in this paper. Some analytical investigations as UV-Vis spectrophotometry (UV-Vis), Fourier transformed infrared spectroscopy (FTIR), atomic force microscopy (AFM) have been discussed as purity and stability criteria. Also, some considerations about their aggregation ability are discussed, and not in the last time, their capacity to generate porphyrin nanotubes.

I propose an integrated multiplexer/demultiplexer that use a concave blazed diffraction grating on SiON wafer. The paper presents a technology that overcome existing issues regarding implementation of such a microoptic device. Two types of similar integrated systems were developed but both of them have not minimized chromatic, astigmatism and spherical aberrations. Both systems use gold coating for vertical walls of diffraction grating that has reflection index lower than aluminum for wavelength used. Technology proposed in this paper minimizes the chromatic, astigmatism and spherical aberrations. Also is used aluminum for coating of vertical walls of diffraction grating. SiON wafer is etched with Argon plasma through photoresist mask with thickness of 0,8 μm for grating configuration allowing reusing of the photoresist in next stage of coating. This makes possible that coating through liftoff to be aligned to vertical walls of concave diffraction grating, eliminating positioning errors due to coating mask.