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Baseline design of the KunLun Turbulence Profiler instrument

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Astronomical Techniques and Instruments 2024年第4期1卷 218-226页

作者： Xiaohui Guo Yi Hu Jing Li Xu Yang zhengzhou Yan School of Physics&Astronomy China West Normal UniversityNanchong 637002China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China university of Chinese Academy of Sciences Beijing 101408China

Adaptive optics systems are the most powerful tools to counteract the image blurring caused by atmospheric turbulence,allowing ground-based telescopes to capture high-resolution images.A critical parameter influencing adaptive optics system performance is the atmospheric refractive index structure constant,C_(n)^(2.,which characterizes the intensity of atmospheric optical turbulence as a function of *** its simplicity,the lunar scintillometer is the preferred method for detecting atmospheric turbulence in challenging environments like Dome A in Antarctica,where sites are still in the developmental stages and local environmental conditions are extremely ***,optimizing the performance of such instruments requires carefully determining the baseline configuration of photon sensors according to each site's specific optical turbulence profile *** study uses a Monte Carlo method to identify the optimal configuration for the KunLun Turbulence Profiler(KLTP),an instrument comparable to the lunar scintillometer,developed for use at Dome *** conducted using the obtained optimal baseline configuration recovered three different model optical turbulence profiles,demonstrating the effectiveness of our method in obtaining an optimal baseline *** approach can be easily applied to baseline design for similar turbulence profilers at other sites.

关键词： KunLun Turbulence Profiler Monte Carlo Simulation Turbulence profile

Local and Global Character Sums

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Acta Mathematica Sinica,English Series 2000年第3期16卷 535-540页

作者： Chunlei Liu zhengzhou university of Information Engineering,zhengzhou {{2.P.R.china zhengzhou university of Information Engineering Zhengzhou 450002 P. R. China

Hua’s estimate is established for character sums in a number field.A relationship between liftings of a character sum in a local field is also studied.

关键词： Character sum Exponential sum

Fracture analysis of a functionally graded interfacial zone between two dissimilar homogeneous materials

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Science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 540-552页

作者： CHENG Zhanqi1,2.& ZHONG Zheng1 1. School of Aerospace Engineering and Applied mechanics, Tongji university, Shanghai 2.0092. china 2. College of Civil Engineering,{2., zhengzhou 450002. china School of Aerospace Engineering and Applied mechanics Tongji University Shanghai China College of Civil Engineering Zhengzhou University Zhengzhou China

In this paper the plane elasticity problem for a functionally graded interfacial zone containing a crack between two dissimilar homogeneous materials has been considered. It is assumed that in the interfacial zone the reciprocal of the shear modulus is a linear function of the coordinate, while Possion’s ratio keeps constant. By utilizing the Fourier transformation technique and the transfer matrix method, the mixed boundary problem is reduced to a system of singular integral equations that are solved numerically. The influences of the geometric parameters and the graded parameter on the stress intensity factors are investigated. The numerical results show that the graded parameters, the thickness of interfacial zone, the crack size and location have significant effects on the stress intensity factors.

关键词： functionally graded material interfacial zone fracture stress intensity factor

The GPS-gravimetry boundary value problem

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Science china Earth Sciences 2005年第3期48卷 398-405页

作者： YU Jinhai1,2.& ZHANG Chuanding2.1. Institute of Geodesy and Geophysics of Chinese Academy of Sciences, Wuhan 430077, {2. 2. zhengzhou Information Engineering {2., zhengzhou 450052. {2. Institute of Geodesy and Geophysics of Chinese Academy of Sciences Wuhan China zhengzhou Information Engineering university Zhengzhou China

How to determine the earth’s external gravity field with the accuracy of O(T2. by making use of GPS data and gravity values measured on the earth’s surface is dealt with in this paper. There are two main steps: to extend these measured values on the earth’s surface onto the reference ellipsoid at first and then to seek for the integral solution of the external Neumann problem outside the ellipsoid. In addition, the corresponding judging criteria of accuracy to solve the GPS-gravity boundary value problem are established. The integral solution given in the paper not only contains all frequency-spectral information of the gravity field with the accuracy of O(T 2., but is also easily computed. In fact, the solution has great significance for both theory and prac- tice.

关键词： Neumann boundary value problem, integral solution, gravity disturbance.

Constructing quantum error correcting code via logic function

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Science china(Information Sciences) 2010年第3期53卷 515-523页

作者： ZHONG ShuQin, MA Zhi & XU YaJie zhengzhou Institute of Information Engineering, university of Information Engineering of {{2., zhengzhou 450002. china zhengzhou Institute of Information Engineering University of Information Engineering of China Zhengzhou China

We present a systematic way to construct p-ary quantum error correcting codes using logic functions. As a consequence, for a given function with APC distance d′ 2. we can construct quantum codes with parameters ((n, K, d))p and gain a lower bound of K for all 2.d d′. The basic states of the constructed quantum codes can be stated and the sufficient conditions for saturating quantum Singleton bound are also discussed. We give quantum codes [[5, 1, 3]]p with p prime, [[6, 0, 4]], [[6, 2. 3]]p with p > 2.prime and [[2., 2. - 2. 2.] as examples constructed in this way.

关键词： quantum error-correcting code logic states APC distance

Enhancement of H_2.Sensing Properties of In_2._3-based Gas Sensor by Chemical Modification with SiO_2

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Chinese Chemical Letters 2004年第12期15卷 1509-1512页

作者： Zi Li ZHAN Deng Gao JIANG Jia Qiang XU School of Chemical Engineering, zhengzhou university, zhengzhou {{2.Department of Chemical Engineering, zhengzhou Institute of Light Industry,zhengzhou 450002 School of Chemical Engineering Zhengzhou University Zhengzhou 450002 China Department of Chemical Engineering Zhengzhou Inst. of Light Industry Zhengzhou 450002 China

The sensitivity and selectivity to H_2.of a new In_2._3-based gas sensor were improvedsignificantly by surface chemical modification. A dense layer of SiO_2.near the surface of the porousIn_2._3 bead was formed by chemical vapor deposition(CVD)of diethoxydimethysilane(DEMS).The dense layer functioned as a molecular sieve, thereby the diffusion of gases with large moleculardiameters,except for H_2. was effectively controlled, resulting in a prominent selectivity and highsensitivity for H_2. The working mechanism of the sensor was also presented.

关键词： H_2.gas sensor indium oxide molecular sieve.

Silicon nanoporous pillar array and its surface copper deposition

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Chinese Science Bulletin 2005年第14期50卷 1424-1428页

作者： FU Xiaonan1,2.3, CHAI Huadou1,2.& LI Xinjian1,2.1. Department of Physics, zhengzhou university, zhengzhou 450052. {2. 2. Key Laboratory of Material Physics (zhengzhou university), Ministry of Education, zhengzhou 450052. {2. 3. Department of Mathematics and Physics, Henan university of Tech- nology, zhengzhou 450052. {2. Department of Physics Zhengzhou University Zhengzhou China Key Laboratory of Material Physics (zhengzhou university) Ministry of Education Zhengzhou China Department of Mathematics and Physics Henan University of Technology Zhengzhou China

Silicon nanoporous pillar array (Si-NPA) has been prepared by a hydrothermal etching technique. Using Si-NPA as substrate, a Cu/Si-NPA nanocomposite thin film has been obtained with immersion plating method. Morpho- logical and structural analysis indicates that Si-NPA is a typical structural composite system characterized by a triple hierarchical structure, i. e. the array of micron-sized silicon pillars, the nanopores densely distributed on the surface of the pillars, and the silicon nanocrystallites that constitute the pore walls. Cu/Si-NPA inherits the morphological character- istics of Si-NPA. The compactability of the deposited copper nanoparticles varies alternatively with the local geometrical features of Si-NPA and forms a quasi-periodical pattern. Such an experimental phenomenon is attributed to the veloc- ity dependence of the copper deposition upon the local geo- metrical features of Si-NPA. These results indicate that Si-NPA might be used as an ideal template for preparing specially patterned, structured or functionalized metal/ sili- con nanocomposite systems.

关键词：硅元素薄膜蚀刻技术电镀技术

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铁路客车技术整备所线路配置规模研究

中国铁路 2024年第5期 118-123页

作者：张雄张正舟中铁二院工程集团有限责任公司四川成都610031 中国铁路经济规划研究院有限公司北京100038

合理确定铁路客车技术整备所的整备线和车底停留线配置规模,对于节约用地和降低工程投资非常重要。TB 1002.—2.09《铁路客车车辆设备设计规范》第4.3.2.规定,按入所列车数量确定线路数量,并给出相应的计算表。结合规范修订工作,采用... 详细信息

合理确定铁路客车技术整备所的整备线和车底停留线配置规模,对于节约用地和降低工程投资非常重要。TB 1002.—2.09《铁路客车车辆设备设计规范》第4.3.2.规定,按入所列车数量确定线路数量,并给出相应的计算表。结合规范修订工作,采用线性回归法和概率分析法对线路配置规模进行研究,并对该条规定在当前的适用性进行验证。研究结论如下:(1)按照列车运行图确定客车车底出入客车技术整备所的时间,分析其最大车底停留数量,从而确定整备线和车底停留线数量之和的方法,是确定客车技术整备所线路数量的准确方法。(2.按照入所车底数量和配置系数确定线路数量方法可行,全路客车技术整备所计算平均数量与运行图分析法计算结果的误差为0.3%~7.5%,符合性较好。(3)将3种计算方法应用到具体铁路客车整备所时,全路各所的均方根误差为2.%~2.%,该误差受运行图编制主客观因素影响,由各客运站列车终到/始发时间分布规律差异造成,可通过运行图调整来适应。

关键词：铁路客车整备所整备线停留线线路配置规模

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Effects of Al on Microstructure and High-Temperature Wear Properties of Austenitic Heat-Resistant Steel

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Journal of Iron and Steel Research International 2012年第3期19卷 62-66页

作者： ZHANG Yan1, SUN Yu-fu2. ZHAO Jing-yu2. GUAN Shao-kang2.(1. School of Materials Engineering, Nanjing Institute of Technology, Nanjing 2.1167, Jiangsu, china 2. School of Materials Science and Engineering, zhengzhou university, {2. 450002. Henan, china) School of Materials Engineering Nanjing Institute of Technology Nanjing Jiangsu China School of Materials Science and Engineering Zhengzhou University Zhengzhou Henan China

Microstructure and high-temperature dry sliding wear at 600 ~C in ambient air of austenitic heat-resistant steel ZG40Cr2.Ni2. with different contents （mass percent） of AI （0 to 7.10~） have been investigated. The results show that microstructures of 4.68% and 7.10% A1 addition content consist of the matrix and reinforcement of inter- metallic compound y＇ and carbide, while microstructures of ZG40Cr2.Ni2. without A1 and with A1 of 1.68% are ab- sent of y＇. Higher wear resistance than the original ZG40Cr2.Ni2. alloy is achieved in alloys with higher content of A1 under the same high-temperature wear test condition. The wear rates of Fe-2.Cr-2.Ni-7.10A1 and Fe-2.Cr-2.Ni- 4.68A1 are only 2..83% and 45.83% of that of Fe-2.Cr-2.Ni, respectively. Heat-resistant steels with higher con- tents of AI （4.72. and 7.10%） have higher hardness than those with lower contents of AI （1.68% and 0）. Wear mechanisms of ZG40Cr2.Ni2. are considered as severe plough plastic deformation and slight adhesive. However, wear mechanisms of Fe-2.Cr-2.Ni 4.68A1 are light micro-cutting and oxidation-wear, while that of Fe-2.Cr-2.Ni- 7. 10A1 are severe adhesive transfer and oxidation-wear_

关键词： austenitic heat resistant steel Al microstructure high-temperature sliding wear mechanism