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折/衍混合光学系统在纳型星敏感器中的应用

光子学报 2024年第6期53卷 251-263页

作者：邓骞张国玉孟遥孙高飞杜宗育长春理工大学光电工程学院长春130022 光电测控与光电信息传输技术教育部重点实验室长春130022 吉林省光电测控仪器工程技术研究中心长春130022

微纳卫星是一种新兴的微小卫星,与之适配的纳型星敏感器的光学系统应在小型化的同时实现大相对孔径、高成像质量。针对这一需求,由星敏感器的系统设计精度和探测星等分配了光学系统设计参数及指标,设计了一种全视场17°、焦距25 mm、相... 详细信息

微纳卫星是一种新兴的微小卫星,与之适配的纳型星敏感器的光学系统应在小型化的同时实现大相对孔径、高成像质量。针对这一需求,由星敏感器的系统设计精度和探测星等分配了光学系统设计参数及指标,设计了一种全视场17°、焦距25 mm、相对孔径1∶1.086、光学系统总长36.4 mm的七片式折衍混合结构的星敏感器光学系统。根据衍射元件的负色散特性,用折衍混合透镜代替常规材料正负透镜组合的方式减少了镜片数量,缩短了光学系统长度,并提高了光学系统的成像质量,使点扩散函数趋于正态分布,有利于质心提取精度的提高。所设计的光学系统在3×3像元内的能量集中度超过90%;最大畸变仅0.013%;全视场垂轴色差小于0.6μm。通过标量衍射理论计算衍射元件在520~780 nm内衍射效率可以达80%以上,通过杂散光分析软件ASAP对系统进行了视场内鬼像分析,系统在多级衍射时探测目标成像光斑路径下的光通量与最亮鬼像光斑路径下的光通量之比大于3.17×10^(4),验证了在极限星等为6.5时满足信噪比大于8.1的结论。最后对所设计的系统进行了公差分析,结果表明加工后该光学系统可满足微纳卫星对星敏感器的使用要求。

关键词：纳型星敏感器光学设计折衍混合光学系统大相对孔径衍射面鬼像

基于Isabelle/HOL的文件系统形式化设计与验证

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计算机工程 2024年第4期50卷 277-285页

作者：王文斌钱振江靳勇孙高飞邢晓双苏超孙天琦苏州大学计算机科学与技术学院江苏苏州215000 常熟理工学院计算机科学与工程学院江苏苏州215500

对于构建可信操作系统而言,文件系统设计和实现的正确性至关重要,即使是已经得到广泛运用的文件系统仍然有漏洞被检测出来。采用形式化方法对文件系统的设计和实现的正确性进行严格的验证是公认的可行方法。当前文件系统的形式化验证工... 详细信息

对于构建可信操作系统而言,文件系统设计和实现的正确性至关重要,即使是已经得到广泛运用的文件系统仍然有漏洞被检测出来。采用形式化方法对文件系统的设计和实现的正确性进行严格的验证是公认的可行方法。当前文件系统的形式化验证工作大多基于宏内核操作系统,而忽视了微内核操作系统架构下文件系统的验证。为此,提出一种微内核架构下采用内联数据机制的文件系统的形式化设计和验证方法。以高阶逻辑(HOL)和自动机模型为基础,将文件系统中的工作对象和系统资源抽象为系统对象来构建文件系统的工作状态,形式化地描述文件系统的相关系统调用的功能语义,将系统调用提供服务的过程抽象为系统工作状态发生跃迁的过程,并给出文件系统功能正确性和安全属性的断言。以实现的安全可信微内核操作系统(VSOS)中的安全可信文件系统(VSFS)为例,在设计阶段构建VSFS的有限状态机模型,并在Isabelle/HOL中抽象描述VSFS的可移植操作系统接口(POSIX)系统调用,分析和归纳出VSFS文件系统正确性断言,使用定理证明的方式来验证VSFS的正确性。实验结果表明,该方法在Isabella/HOL中完成VSFS有限状态机模型细粒度的形式化验证,满足预期的安全需求规范。

关键词：形式化验证文件系统定理证明有限状态机微内核

A measurable refinement method of design and verification for micro-kernel operating systems in communication network

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Digital Communications and Networks 2023年第5期9卷 1070-1079页

作者： Zhenjiang Qian Rui Xia gaofei sun Xiaoshuang Xing Kaijian Xia School of Computer Science and Engineering Changshu Institute of TechnologySuzhou215500China Changshu Hospital of Soochow University Jiangsu215500ChangshuChina

A secure operating system in the communication network can provide the stable working environment,which ensures that the user information is not *** micro-kernel operating system in the communication network retains the core functions in the kernel,and unnecessary tasks are implemented by calling external *** to the small amount of code,the micro-kernel architecture has high reliability and *** the microkernel operating system in the communication network prototype VSOS as an example,we employ the objdump tool to disassemble the system source code and get the assembly layer *** this basis,we apply the Isabelle/HOL,a formal verification tool,to model the system *** referring to the mathematical model of finite automata and taking the process scheduling module as an example,the security verification based on the assembly language layer is *** on the Hoare logic theory,each assembly statement of the module is verified in *** verification results show that the scheduling module of VSOS has good functional security,and also show the feasibility of the refinement framework.

关键词： Assembly-level verification Finite automaton Hoare logic Isabelle/HOL Micro-kernel OS

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同轴零盲区米散射激光雷达系统仿真与设计

应用激光 2024年第3期44卷 142-149页

作者：李东旭孙高飞衣文索蒋雨辰赵瑞安长春理工大学光电工程学院吉林长春130022

针对传统米散射激光雷达近距离探测盲区大的缺陷,设计一款同轴的米散射激光雷达气溶胶探测系统。首先,通过美国标准大气模型和激光雷达系统参数对系统回波信噪比进行了数值模拟研究。主要讨论激光脉冲能量、雷达接收口径、脉冲累加数对... 详细信息

针对传统米散射激光雷达近距离探测盲区大的缺陷,设计一款同轴的米散射激光雷达气溶胶探测系统。首先,通过美国标准大气模型和激光雷达系统参数对系统回波信噪比进行了数值模拟研究。主要讨论激光脉冲能量、雷达接收口径、脉冲累加数对回波信噪比的影响。仿真结果表明,提高发射激光脉冲能量、增加雷达接收口径、增加脉冲累加数都可以提高回波信噪比,其中,增加雷达接收口径对回波信噪比的提升最为明显。其次,设计平衡探测器对散射回光进行光电转换。最后,基于系统结构搭建了可移动式米散射激光雷达实验平台,对大气气溶胶进行初步探测,试验结果表明:提高发射激光脉冲能量对探测距离的影响不大,该系统的有效探测距离在约10 km;平衡探测法相对于直接探测法信噪比提高了2.7倍;系统的同轴设计使得近距离探测盲区几乎为0,空间分辨率可以达到120 m。

关键词：米散射大气气溶胶数值模拟盲区

Expression patterns and functional divergence of homologous genes accompanied by polyploidization in cotton(Gossypium hirsutum L.)

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Science China(Life Sciences) 2020年第10期63卷 1565-1579页

作者： Zhen Peng Hua Cheng gaofei sun Zhaoe Pan Xiao Wang Xiaoli Geng Shoupu He Xiongming Du Research Base Anyang Institute of TechnologyState Key Laboratory of Cotton Biology/Institute of Cotton ResearchChinese Academy of Agricultural Science(ICRCAAS)Anyang 455000China Zhengzhou Research Base State Key Laboratory of Cotton BiologyZhengzhou UniversityZhengzhou 450001China Anyang Institute of Technology Anyang 455000China

Naturally allotetraploid cotton has been widely used as an ideal model to investigate gene expression remodeling as a consequence of ***,the global gene pattern variation during early fiber development was *** this study,through RNA-seq technology,we comprehensively investigated the expression patterns of homologous genes between allotetraploid cotton(***)and its diploid progenitors(*** and ***)at the fiber early development *** tetraploid cotton,genes showed expression level dominance(ELD)bias toward the A *** phenomenon was explained by the up-/downregulation of the homologs from the nondominant progenitor(D genome).Gene ontology(GO)enrichment results indicated that the ELD-A genes might be a prominent cause responsible for fiber property change through regulating the fatty acid biosynthesis/metabolism and microtubule procession,and the ELD-D genes might be involved in transcription regulation and stress *** addition,the number and proportion of completely A-and D-subfunctionalized gene were similar at different fiber development ***,for neofunctionalization,the number and proportion of reactivated D-derived genes were greater than those of A at 3 and 5 ***,we found that some homologous genes belonging to several specific pathways might create novel asymmetric transcripts between two subgenomes during polyploidization and domestication process,further making the fiber property meet the human *** study identified determinate pathways and their involved genes between allotetraploid cotton and their progenitors at early fiber development stages,providing new insights into the mechanism of cotton fiber evolution.

关键词： Gossypium fiber development polyploid evolution expression level dominance sub-and neofunctionalization

Design of Optical and Mechanical Structure for Lunar Simulator Based on Variable Shape and Adjustable Radiance

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空间科学学报 2015年第5期35卷 647-652页

作者： LIU Shi ZHANG Guoyu sun gaofei WANG Lingyun GAO Yujuni College of Optoelectronic Engineering Changchun University of Science and Technology Optical Measurement and Control Instrumentation Jilin Province Engineering Research Center Changchun Institute of Optics Fine Machines and PhysicsChinese Academy of Sciences

To simulate the different lunar phases and ensure continuous adjustability of the radiant brightness,a new broad spectrum light and frosted glass were applied and designed in the optical system for lunar simulator with the shapes and radiance being able to be *** to the engineering demand and index requirements of the optical system,three major design aspects are addressed,including the high reliability and maintainability for broad-spectrum light,heat dissipation in lunar simulator for long working hours,and bearing of the main frame under different working *** designing a reasonable machine structure,and through the structure itself with the matrix arrangement of 48 axial flow fans,an effectively cooling air duct is *** and temperature were calculated by the finite element software *** results showed that the displacement deformation reached 0.33 mm and stress deformation reached 0.02 MPa at the temperature of 20℃;when the main frame was in the temperature field between 20℃ and65℃,the maximum displacement deformation reached 13.30 mm and maximum stress deformation is 97.90 MPa,and the amount of this deformation is very small in considering of the mechanical structure dimensions and weight of the lunar simulator.

关键词： Lunar simulator Adjustable shapes and radiance Opt

Comparative effect of allopolyploidy on transposable element composition and gene expression between Gossypium hirsutum and its two diploid progenitors

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Journal of Integrative Plant Biology 2019年第1期61卷 45-59页

作者： Hua Cheng gaofei sun Shoupu He Wenfang Gong Zhen Peng Ruiping Wang Zhongxu Lin Xiongming Du Research Base Anyang Institute of TechnologyState Key Laboratory of Cotton BiologyInstitute of Cotton Researchthe Chinese Academy of Agricultural Science College of Plant Science & Technology of Huazhong Agricultural University Department of Computer Science and Information Engineering Anyang Institute of Technology

An allopolyploidization event formed allotetraploid Gossypium species from an A-genome diploid species and a D-genome diploid species. To explore the responses of transposable elements(TEs) to allopolyploidy, we assembled parallel TE datasets from G. hirsutum, G. arboreum and G. raimondii and analyzed the TE types and the effects of TEs on orthologous gene expression in the three Gossypium *** was the most abundant TE type and most TEs were located $500 bp from genes in all three genomes. In G. hirsutum, 35.6% of genes harbored TE insertions, whereas insertions were more frequent in G. arboreum and G. raimondii. G. hirsutum had the highest proportion of uniquely matching 24-nt small interfering RNAs(siRNAs) that targeted TEs. TEs,particularly those targeted by 24-nt siRNAs, were associated with reduced gene expression, but the effect of TEs on orthologous gene expression varied substantially among species. Orthologous gene expression levels in G. hirsutum were intermediate between those of G. arboreum and G. raimondii, which did not experience TE expansion or reduction resulting from allopolyploidization. This study underscores the diversity of TEs co-opted by host genes and provides insights into the roles of TEs in regulating gene expression in Gossypium.

关键词： progenitors allopolyploidization

A Light Source System of Multi-star Simulator with Adjustable Background and Controllable Magnitude

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空间科学学报 2017年第6期37卷 760-765页

作者： sun gaofei LIU Shi ZHANG Guoyu ZHANG Yu LEI Jie MA Yiyuan College of Optoelectronic Engineering Changchun University of Science and Technology Changchun 130022 Optical Measurement and Control Instrumentation Jilin Province Engineering Research Center Changchun 130022 Key Laboratory of Space System Simulation Beijing 100853

A light source of multi-star simulator capable of background adjustment and magnitude control has been *** integrating spheres are employed as the star-point light source and the background light source respectively.A beam splitter prism has been designed to serve as the beam combiner for the star-point and the background light sources,and a mathematical model has been constructed respectively to compute the light flux of the two integrating spheres.A magnitude testing system and a background testing system have been created using low-light illuminometer,luminance meter,and testing instruments to measure the star-point magnitude and the background luminance of the multi-star *** test results suggest that the star-point magnitude is adjustable from0 to+5 m_v,with a simulation precision superior to ±0.026 m_*** maximum background luminance is 3.8×10~5 cd·m^(-2),and the minimum background luminance is6.4×10^(-2)cd·m^(-2).The designed light source system can meet the requirements for simulating the stellar map with a sky background.

关键词： Adjustable background Controllable magnitude Multi-Star simulator Light source

Star Point Energy Center Correction of Star Simulator Based on Polar Coordinates

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空间科学学报 2016年第3期36卷 407-412页

作者： WANG Lingyun WANG Xinghua WANG Bo ZHANG Guoyu sun gaofei LIU Shi LI Wenjun Changchun University of Science and Technology Changchun 130022 Jilin Engineering Research Center of Photoelectric Measurement and Control Instrument Changchun 130022 Tianjin Jinhang Institute of Technical Physics Tianjin 300308

In this paper,various aberrations have been *** only the effects of aberration on geometrical center position are taken into account,but also the deviation of displayed star position energy center caused by aberration is *** two aspects have been taken into comprehensive evaluation and star position *** correction method based on polar coordinates is proposed,and cumbersome partition correction and calculated quantity based on two-dimensional coordinates can be *** experimental results show that the correction processing based on polar coordinates is simpler and easier compared with any other correction *** addition,the correction results are significantly more accurate.

关键词： Aberration Energy center Correction Polar coordinates