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A 2.5 ppm/degrees C Voltage Reference Combining Traditional BGR and ZTC MOSFET High-Order Curvature Compensation 期刊论文 OAI收割
IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS II-EXPRESS BRIEFS, 2021, 卷号: 68, 期号: 4, 页码: 1093-1097
作者: Liu, Xifeng; Liang, Shan; Liu, Wenju; Sun, Ping

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收藏 | 浏览/下载：34/0 | 提交时间：2021/05/17

Voltage reference ZTC curvature compensation a power model CMOS process PSRR

The braking index of PSR B0540-69 and the associated pulsar wind nebula emission after spin-down rate transition 期刊论文 OAI收割
Monthly Notices of the Royal Astronomical Society, 2020, 卷号: 494, 页码: 1865-1870
作者: HXMT

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收藏 | 浏览/下载：54/0 | 提交时间：2022/02/08

stars: magnetic field stars: neutron pulsars: general Astrophysics - High Energy Astrophysical Phenomena Abstract: In 2011 December, PSR B054-69 experienced a spin-down rate transition (SRT), after which the spin-down power of the pulsar increased by $\sim 36{{\ \rm per\ cent}}$. About 1000 d after the SRT, the X-ray luminosity of the associated pulsar wind nebula (PWN) was found to brighten by $32\pm 8{{\ \rm per\ cent}}$. After the SRT, the braking index n of PSR B0540-69 changes from n = 2.12 to 0.03 and then keeps this value for about five years before rising to n = 0.9 in the following years. We find that most of the current models have difficulties in explaining the measured braking index. One exceptive model of the braking index evolution is the increasing dipole magnetic field of PSR B0540-69. We suggest that the field increase may result from some instabilities within the pulsar core that enhance the poloidal component at the price of toroidal component of the magnetic field. The increasing dipole magnetic field will result in the X-ray brightening of the PWN. We fit the PWN X-ray light curve by two models: one assumes a constant magnetic field within the PWN during the brightening and the other assumes an enhanced magnetic field proportional to the energy density of the PWN. It appears that the two models fit the data well, though the later model seems to fit the data a bit better. This provides marginal observational evidence that magnetic field in the PWN is generated by the termination shock. Future high-quality and high-cadence data are required to draw a solid conclusion.

Effect of design parameters on the reduction of top piston ring friction (EI CONFERENCE) 会议论文 OAI收割
2nd International Conference on Computer-Aided Design, Manufacturing, Modeling and Simulation, CDMMS 2012, September 21, 2012 - September 23, 2012, Chongqing, China
作者: Wang P.

收藏 | 浏览/下载：137/0 | 提交时间：2013/03/25

In order to reduce ring-liner interface friction power loss this paper focuses on the structure parameters of the top ring and investigates how the value of those parameters will influence top ring-liner friction power loss and the minimum thickness of oil film at top ring-liner interface. A mixed lubrication model is developed to simulate the effect of varying design parameters on ring-liner friction. Case study shows that ring-liner friction power loss will be reduced with decreased axial ring height and barrel height. This study provides a theoretical basis for design the top ring with reduced friction power loss at ring-liner interface. (2013) Trans Tech Publications Switzerland.

Structural design and simulation analysis of ejector used in automotive power steering oil discharge equipment (EI CONFERENCE) 会议论文 OAI收割
2012 International Conference on Mechanical Engineering, Materials Science and Civil Engineering, ICMEMSCE 2012, August 18, 2012 - August 20, 2012, Harbin, China
Cheng K.; Zou H.; Kong X.; Tang J.

收藏 | 浏览/下载：26/0 | 提交时间：2013/03/25

The structure of ejector used in automotive power steering oil discharge equipment is designed in accordance with the theory of gas-liquid ejector.The two important parameters of the ejector are elected respectively to five values and then 25 ejector models are obtained by the permutations and combinations.The ejector's CFD model is created by Fluent module of Ansys then it is divided into a grid and analyzed. Analyse its pressure distribution and velocity vector which provides the optimal size for the manufacture of the ejectors and a theoretical basis for experiment. (2013) Trans Tech Publications Switzerland.

Evaluation of the operating range for ground-based infrared imaging tracking system (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China
作者: Zhang Z.-D.

收藏 | 浏览/下载：47/0 | 提交时间：2013/03/25

Ground-based infrared imaging tracking system (GIITS) is of great importance for aerial target warning and guard. The operating range is one of the key performance specifications on the other which should be calculated calculate the radiation power received on the detector in order to analysis whether the output signal meets the detection requirements or not analyzed and studied during the whole GIITS design process. The operating range is mostly influenced by a few factors without considering the effect of the background radiation. By improving of the traditional method including atmospheric attenuation a new operating range calculation model of the GIITS was established based on two requirements. One is that the image size of observed target should meet the requirement of the processor signal extraction. The number of the pixel occupied by target image should be more than 9. The other is that the signal noise ratio (SNR) of the GIITS should not be less than 5 to meet the requirements of the target detection probability and spatial frequency. The SNR calculation equation in form of energy is deduced and the radiation characteristic of the observed target and background are analyzed. When evaluate the operating range of the GIITS using the new method the performance of GIITS and feature of target and background. This paper firstly makes analysis and summarization on the definite localizations of the traditional operating range equation of the GIITS. The localizations are mainly in two aspects. On one hand we should successively calculate two operating range values according to two requirements mentioned above and choose the minimum value as the analytic result. In the end the dispersion of the image and the effect of image dispersion are not considered in the traditional method an evaluation of operating range for fighter aircraft is accomplished as an example. The influence factors in every aspect on operating range were explored by the calculated result. The new operating range calculation model provides the theoretical basis for the design and applications as well as the comprehensive evaluation of a GIITS. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).

The flow field analysis of the automotive power streering congtrol unit's flow channel (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Advanced Design and Manufacturing Engineering, ADME 2011, September 16, 2011 - September 18, 2011, Guangzhou, China
Cheng K.; Yan L.; Li G.; Tang J.

收藏 | 浏览/下载：16/0 | 提交时间：2013/03/25

The automotive power steering units must be taken performance test after they are integrated assembly and then left the factory if it is qualified.Because its internal flow channel is very complicated and the residual hydraulic oil can not be eleminated clearly.So we can set up a 3D model flow channel based on CATIA and use FLUENT software to analysis the key flow channel analysing it's pressure distribution and velocity vector diagram then get the real reasonable resluts which can provide the basic for the ejector designing. (2011) Trans Tech Publications.

Experiment analysis of CO2 laser disturbance on long-wave infrared HgCdTe detector (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Electric Information and Control Engineering, ICEICE 2011, April 15, 2011 - April 17, 2011, Wuhan, China
作者: Wang S.-W.

收藏 | 浏览/下载：23/0 | 提交时间：2013/03/25

Theoretical analysis and experimental study were carried out on the high-power CO2 laser disturbance to long-wave infrared (LWIR) HgCdTe detector in this paper. Based on the practical parameters of experiment the theoretical model of temperature-rise is adopted to calculate the variation of the temperature with the time and the power of laser for laser irradiation on the detector. After that the damage threshold is 110W/cm2. This experimental phenomenon well agrees with the results predicted by the theoretical calculation. The conclusions have a certain reference value for the laser defense of detector. 2011 IEEE. the high-power laser damage mechanism to LWIR detector is discussed and compares with the experimental results of laser irradiation the detector on the distance of 15km. The theoretical and experimental results demonstrate that the interference threshold of the detector is 20.5W/cm 2

Study on annular polishing for a rectangle optical flat with high aspect ratio (EI CONFERENCE) 会议论文 OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, April 26, 2010 - April 29, 2010, Dalian, China
作者: Li J.; Li J.; Li J.

收藏 | 浏览/下载：20/0 | 提交时间：2013/03/25

The annular polishing is used to manufacture a rectangle optical flat with high aspect ratio in this paper. To control the polishing conveniently a theoretical model based on the Preston hypothesis is given. According to the model the problems related to control the power and the edge effect occurred during the process are analyzed and practically solved. Finally the surface PV of 60 nm was achieved. 2010 Copyright SPIE - The International Society for Optical Engineering.

Super-resolution using adaptive blur parameter estimation (EI CONFERENCE) 会议论文 OAI收割
2010 6th International Conference on Wireless Communications, Networking and Mobile Computing, WiCOM 2010, September 23, 2010 - September 25, 2010, Chengdu, China
作者: Wang H.; Wang H.; Wang H.; Wang H.; Liu G.

收藏 | 浏览/下载：15/0 | 提交时间：2013/03/25

Super-resolution is a term for a set of methods of increasing image or video resolution. All these methods are based on the same idea: using information from several images to create one upsized image. In most of the super-resolution algorithms the blur parameter of a LR-image model is always manually set as a default value. In this paper we propose a method to adaptively estimate the blur parameter. We get the initial image of iteration by fusing all low-resolution images. When it is used in MAP algorithm three iterations are enough to get a stable solution. It is greatly reduce the computational power compared with other MAP algorithms. Experiments to real image sequences show that it well preserved the image detail and the reconstructed image is clear. 2010 IEEE.

Analysis of laser jamming to satellite-based detector (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2009: Laser Sensing and Imaging, June 17, 2009 - June 19, 2009, Beijing, China
作者: Guo L.-H.; Guo R.-H.; Wang S.-W.

收藏 | 浏览/下载：29/0 | 提交时间：2013/03/25

The reconnaissance satellite communication satellite and navigation satellite used in the military applications have played more and more important role in the advanced technique wars and already become the significant support and aid system for military actions. With the development of all kinds of satellites anti-satellite laser weapons emerge as the times require. The experiments and analyses of laser disturbing CCD (charge coupled detector) in near ground have been studied by many research groups but their results are not suitable to the case that using laser disturbs the satellite-based detector. Because the distance between the satellite-based detector and the ground is very large it is difficult to damage it directly. However the optical receive system of satellite detector has large optical gain so laser disturbing satellite detector is possible. In order to determine its feasibility the theoretical analyses and experimental study are carried out in the paper. Firstly the influence factors of laser disturbing satellite detector are analyzed in detail which including laser power density on the surface of the detector after long distance transmission and laser power density threshold for disturbing etc. These factors are not only induced by the satellite orbit but dependence on the following parameters: laser average power in the ground laser beam quality tracing and aiming precision and atmospheric transmission. A calculation model is developed by considering all factors which then the power density entering into the detector can be calculated. Secondly the laser disturbing experiment is performed by using LD (laser diode) with the wavelength 808 nm disturbing CCD 5 kilometer away which the disturbing threshold value is obtained as 3.5510-4mW/cm2 that coincides with other researcher's results. Finally using the theoretical model the energy density of laser on the photosensitive surface of MSTI-3 satellite detector is estimated as about 100mW/cm2 which is largely exceed the disturbing threshold and therefore verify the feasibility of using this kind of laser disturbing the satellite-based detector. According to the results. using the similar laser power density absolutely saturate the requirements to laser disturbing satellite-based detector. If considering the peak power of pulsed laser even decrease laser average power it is also possible to damage the detector. This result will provide the reliable evidences to evaluate the effect of laser disturbing satellite-based detector. 2009 SPIE.