Great achievements in modern medicine benefit human beings. Also, it has brought about an explosive growth of pharmaceuticals that current in the market. In daily life, pharmaceuticals sometimes confuse people when they are found unlabeled. In this paper, we propose an automatic pill recognition technique to solve this problem. It functions mainly based on the imprint feature of the pills, which is extracted by proposed MSWT (modified stroke width transform) and described by WSC (weighted shape context). Experiments show that our proposed pill recognition method can reach an accurate rate up to 92.03% within top 5 ranks when trying to classify more than 10 thousand query pill images into around 2000 categories.
In order to study the impact of the thermal environment on the optical performance of the Ha and White light
telescope(HWT), a thermo-optical experimental system is built test the optical performance of the HWT under a thermal
vacuum condition. This system is made up of four sub-systems: an optical system to be tested, a vacuum system, a
temperature measurement and control system, and a wavefront sensing system. The temperature conditions of the
thermo-optical testing are designed on the basis of the measurement and numerical simulation of the ground observing
condition. An integrated STOP test based on the HWT is performed. The optical performances of the HWT under
different vacuum degree and different thermal control conditions are tested using the wavefront sensing system. The
results show that when the temperature of the secondary mirror is below 40°C, the optical performance of HWT is about
λ/8, which satisfies the requirement of λ/6. The secondary mirror structure is the most effect to the system optical
performance, which is the key part improving HWT. After the analytical model of HWT is set up by using the finite
element analysis software MSC.PATRAN/NASTRAN, finite element based optical analysis (FEMOPT) software is
used to calculate the optical performance. The comparison of the temperature control condition simulation and
experimental results show that FEMOPT optical structural thermal integral analysis is reasonable.
The World Space Observatory - Ultraviolet (WSO-UV) is a space astronomy project led by Russia, with contributions
from China, Germany, Italy, Spain, United Kingdom and a number of other countries in the world. WSO-UV consists of
a 1.7-meter diameter telescope and three focal plane science instruments. The Long Slit Spectrograph instrument on-board
WSO-UV will produce moderate spectral resolution (R=1000-2500) spectra in the 102nm ~ 320nm wavelength
range along a slit of 75 arcsec in length and 1 arcsec in width. The spatial resolution of the instrument will be ~1 arcsec.
A two-channel scheme is proposed to optimize performance, with each of these using a Rowland Circle optical design
with Microchannel Plate detectors in the focal plane. We will discuss the detailed design of the spectrograph and its
expected performance in this paper.
The H-alpha and White Light Telescope (HWT), one of the five payloads on board the Space Solar Telescope (SST), is
mainly for the observation of the chromosphere, solar flares and white light of the full solar disc, also as a location
reference for the detailed Main Optical Telescope (MOT). The HWT prototype experiment, structure analysis and modal
testing are discussed. The HWT alignment is addressed. The result of interferometric tests is presented. In order to
realize the mechanical characteristics of Hα and white light telescope (HWT), the analytical model of HWT is set up by
using the finite element analysis software MSC.PATRAN/NASTRAN, and the first several orders of natural frequencies
and modal shapes are calculated with eigenvectors method. Based on modal experiment with free hanging, single input /
multi-output methods, the modal parameters of HWT are identified. The maximum relative error between the experiment
results and the calculated results is 6.4%, and the vibration shapes of experiment are similar to ones of calculation. The
vibration environmental simulation test is accomplished to check the HWT structural strength.
This paper describes the application tendency of beryllium mirror of space astronomical instruments and the tip-tilt
mirror of the correlation tracker of a Space Solar Telescope (SST). The optimization choice of tip-tilt mirror substrate
material, the light-weighted scheme of tip-tilt mirror substrate, the analysis and optimization design of mirror structure
were accomplished. At last, the final RMS surface figure error of 2.18×10-6mm and PV of 1.69×10-5mm were obtained
with resonant frequency of 1609Hz, and the mass of the beryllium mirror of 47.88g. These results satisfy the technology
requirements of the tip-tilt mirror of the correlation tracker. The manufacture technology of beryllium mirror substrate,
the nickel plating technique on beryllium mirror substrate and optical fabrication were discussed in detail.
For the design of a space solar telescope (SST), the large reflect mirror faces to the sun directly, which is in an
abominable thermal condition with seriously thermal distortion. In this paper, it sets up the thermal mode and analyzes
the temperature field and thermal distortion of the main mirror of SST. Further more, it uses the thermal design software
SINDA/G (System Improved Numerical Differencing Analyzer/Gaski) and the finite element analysis software
MSC.Patran to set up different models and various temperature distributions of the main mirror. Though comparing with
these models, the paraboloid mirror model is confirmed, which becomes a reference to later thermal analysis of the
Primary mirror with Φ 1m and f 3.5m is the most important optical part in the space Main Optical Telescope (MOT).
Since its required surface error is less than λ/40(rms.), where λ is about 0.6μm, the mirror deformation induced by space
heat and gravity must be within 0.015μm, it's necessary to make thermal calculation and structural analysis to improve
its structure. In this paper, the MOT structure and its finite element model is described. The mechanical properties are
then analyzed in order to verify whether this structure can meet the optical requirements of sufficient strength, stiffness,
and thermal stability. Mechanical analysis is carried out with MSC.Nastran software under 3 different load cases: gravity
influence on-ground, dynamic impact during launching, weightlessness and heat environment in-orbit. Space thermal
analyses are also done to simulate the space environment. The coupled deformation of heat and structure is finally
analyzed. Calculation results show that different support ways and support forces will be the keys to determine the
surface precision of primary mirror. The structure can meet the optical demands, but the thermal deformation can not,
especially in an asymmetric temperature distribution, which should be tested and controlled by some strict methods.
Primary mirror with Φ 1m and f 3.5m is the most important optical part in Space Solar Telescope (SST), which is
designed to make observations of transient and steady state solar hydrodynamic and magnetohydrodynamic processes
and is being researched and manufactured by National Astronomical Observatories. The primary mirror structure(PMS),
a crucial linker for the optical and other subsystems, includes primary mirror and its supporting frame. Therefore, this
part must satisfy the optical sufficient strength, stiffness, and thermal stability requirements under the space environment
and in the launching process. In this paper the primary mirror structure and its connection are described. The scheme of
modal analysis and experiment is built, according to the specific dynamic requirements of the primary mirror structure in
Space Solar Telescope. The dynamic response on the primary mirror structure is analyzed with MSC.NASTRAN
software. Comparing these results with mode parameters obtained from modal experiment analysis. Modal experiment
uses freely hanging primary mirror structure, simple input multi-output, and modal parameter identification through
CADA-X software. Both results provide evidences to develop this satellite design.
Space frame including satellite platform is the most important structure part in Space Solar Telescope (SST), which is designed to make observations of transient and steady state solar hydrodynamic and magnetohydrodynamic processes. This paper first introduces the space frame, which is not only a crucial linker between the optical and other subsystems but also a mechanical interface for the telescope and launching rocket. It must satisfy the optics with sufficient strength, stiffness, and thermal stability under the space environment and in the launching process. Then the author sets up finite element analysis model by MSC.Patran software and analyzes the mechanical quality under different load cases such as on-ground, during launching and in-orbit. In order to simulate the space environment and evaluate the influence of space heat to the whole space frame, the paper also presents space thermal calculation and analysis. Calculation results show that this space frame can meet the satellite’s requirements in space running. However, the thermal problem is still serious in primary mirror, which needs to be tested and controlled with strict way. Finally, the paper gives conclusions and forward suggestions, which will be applied to further research and fabrication in SST.