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HRRP target recognition based on kernel joint discriminant analysis

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Journal of Systems Engineering and Electronics 2019年第4期30卷 703-708页

作者： LIU Wenbo YUAN Jiawen ZHANG Gong shen qian College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China

With the improvement of radar resolution,the dimension of the high resolution range profile(HRRP)has *** order to solve the small sample problem caused by the increase of HRRP dimension,an algorithm based on kernel joint discriminant analysis(KJDA)is *** with the traditional feature extraction methods,KJDA possesses stronger discriminative ability in the kernel feature space.K-nearest neighbor(KNN)and kernel support vector machine(KSVM)are applied as feature classifiers to verify the classification *** results on the measured aircraft datasets show that KJDA can reduce the dimensionality,and improve target recognition performance.

关键词： high resolution range profile(HRRP) target recognition small sample problem feature extraction dimension reduction

Neural compositing for real-time augmented reality rendering in low-frequency lighting environments

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Science China(Information Sciences) 2021年第2期64卷 139-153页

作者： shengjie MA qian shen Qiming HOU Zhong REN Kun ZHOU State Key Lab of CAD&CG Zhejiang University ZJU-FaceUnity Joint Lab of Intelligent Graphics

We present neural compositing, a deep-learning based method for augmented reality rendering,which uses convolutional neural networks to composite rendered layers of a virtual object with a real photograph to emulate shadow and reflection effects. The method starts from estimating the lighting and roughness information from the photograph using neural networks, renders the virtual object with a virtual floor into color, shadow and reflection layers by applying the estimated lighting, and finally refines the reflection and shadow layers using neural networks and blends them with the color layer and input image to yield the output image. We assume low-frequency lighting environments and adopt PRT(precomputed radiance transfer) for layer rendering, which makes the whole pipeline differentiable and enables fast end-to-end network training with synthetic scenes. Working on a single photograph, our method can produce realistic reflections in a real scene with spatially-varying material and cast shadows on background objects with unknown geometry and material at real-time frame rates.

关键词： augmented reality neural networks differentiable renderer reflection shadow

Equation of State for Neutralino Star as a Form of Cold Dark Matter

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Communications in Theoretical Physics 2008年第1期49卷 212-216页

作者： REN Jie LI Xue-qian shen Hong Department of Physics Nankai University Tianjin 300071 China

In order to study the structure of neutralino star and dark galaxy, we consider dynamical interactions due to boson-exchange in the neutralino matter. Taking into account interactions of neutralinos with bosons, we derive the equation of state （EOS） of neutralino stars in terms of the relativistic mean-field approach. Then we apply the resulting EOS to investigate properties of the neutralino star such as its density profile and mass limit. For example, if the neutralino mass is around 1 TeV, the Oppenheimer mass limit of the neutralino star is obtained as 6.06 ×10^-7 M⊙, and the corresponding radius is about 7.8 mm. Actually, due to an increasing annihilation rate as indicated by our calculation, this dense state can never be realized in practice. Our results also show that the low-density neutralino star may be a possible aggregation of the cold dark matter.

关键词： neutralino star equation of state dark matter

Transcriptional regulation of artemisinin biosynthesis in Artemisia annua L.

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Science Bulletin 2016年第1期61卷 18-25页

作者： qian shen Tingxiang Yan Xueqing Fu Kexuan Tang Key Laboratory of Urban Agriculture (South) Ministry of Agriculture Plant Biotechnology Research Center Fudan-SJTU-Nottingham Plant Biotechnology R&D Center School of Agriculture and Biology Shanghai Jiao Tong University

Artemisinin, also known as qinghaosu, a sesquiterpene endoperoxide lactone isolated from the Chinese medicinal plant Artemisia annua L., is the most effective antimalarial drug which has saved millions of *** to its great antimalarial activity and low content in wild A. annua plants, researches focused on enhancing the artemisin yield in plants became a hotspot. Several families of transcription factors have been reported to participate in regulating the biosynthesis and accumulation of *** this review, we summarize recent investigations in these fields, with emphasis on newly identified transcription factors and their functions in artemisinin biosynthesis regulation, and provide new insight for further research.

关键词： Artemisia annua L. Artemisinin ,Transcription factor Biosynthesis

Mechanically scanned leaky-wave antenna based on a topological one-way waveguide

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Frontiers of physics 2020年第3期15卷 97-103页

作者： qian shen Yun You Jie Xu Yun shen Xiaohua Deng Zhuoyuan Wang Weidong Min Linfang shen Sanshui Xiao Information Engineering School Nanchang UniversityNanchang330031China Institute of Space Science and Technology Nanchang UniversityNanchang330031China Department of Photonics Engineering Technical University of DenmarkDK-2800Kgs.LyngbyDenmark Electronic and Information Engineering College Ningbo University of TechnologyNingbo315016China School of Software Nanchang UniversityNanchang330031China Department of Applied Physics Zhejiang University of TechnologyHangzhou310023China

We propose a uniform backfire-to-endfire leaky-wave antenna(LWA)based on a topological one-way waveguide under external bias magnetic *** systematically analyze the dispersion,showing that the proposed structure supports leaky mode arisen from total internal *** means of tuning frequency or magnetic field,we obtain fixed-bias frequency and fixed-frequency bias LWA with continuous beam scanning from backward,broadside to forward *** importantly,we,for the first time,demonstrate that this proposed LWA shows mechanical tunability,allowing us to manipulate the radiation direction from backward,broadside to forward direction by mechanically tuning the air layer *** simulated results show that our system exhibits super low 3dB beam width,high radiation efficiency as well as high antenna *** provided such multiple controlled(especially mechanically)beam scanning manners,the present LWA paves an advanced approach for continuous beam scanning,holding a great potential for applications in modern communication and radar system.

关键词： leaky-wave antenna one-way waveguide magneto-optic materials

Plant diversity in Yunnan:Current status and future directions

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Plant Diversity 2020年第4期42卷 281-291页

作者： Li-shen qian Jia-Hui Chen Tao Deng Hang Sun CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming650201China University of Chinese Academy of Sciences Beijing100049China School of Life Science Yunnan UniversityKunming650091China

Yunnan,located in southwestern China,harbors more than 19,000 higher plants,which represents the highest plant diversity in the ***,plant diversity in Yunnan faces enormous threats today,including habitat destruction and fragmentation,environmental pollution,and over-exploitation of natural *** recent efforts to protect biodiversity,there are still thousands of threatened species,some of which have become *** analyzed available data to gain a greater understanding of plant diversity and the status of plant conservation in *** found that southern,southeastern,and northwestern Yunnan are hotspots of total species,endemic species,specimens,new species and threatened species,whereas southeastern Yunnan is a hotspot for plant species with extremely small ***,we found that there are still conservation gaps and poorly protected areas in central,eastern,and northeastern *** conclude that conservation of plant diversity in Yunnan requires modern field investigation,systematic research,the development of comprehensive databases,and government *** recommend that conservationists pay more attention to building and improving functional protection systems and popularizing science.

关键词： Biodiversity Conservation status Protection Yunnan Province Hotspot

Programmed death-1 upregulation is correlated with dysfunction of tumor-infiltrating CD8^(+ ) T lymphocytes in human non-small cell lung cancer

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Cellular & Molecular Immunology 2010年第5期7卷 389-395页

作者： Yan Zhang shengdong Huang Dejun Gong Yanghua Qin qian shen Department of Laboratory Diagnosis Changhai HospitalSecond Military Medical UniversityShanghaiChina Institute of Cardiothoracic Surgery Changhai HospitalSecond Military Medical UniversityShanghaiChina

T-cell tolerance is an important mechanism for tumor escape,but the molecular pathways involved in T-cell tolerance remain poorly *** remains unknown whether the inhibitory immunoreceptor programmed death-1(PD-1)plays a role in conditions of human non-small cell lung cancer(NSCLC).In this study,we detected PD-1 expression on CD81 T cells from healthy control peripheral blood mononuclear cells(PBMCs)and the PBMCs of NSCLC patients as well as NSCLC *** showed that tumor-infiltrating CD81 T cells had increased PD-1 expression and impaired immune function,including reducing cytokine production capability and impairing capacity to *** of the PD-1/PD-L1 pathway by the PD-L1-specific antibody partially restored cytokine production and cell *** data provide direct evidence that the PD-1/PD-L1 pathway is involved in CD81 T-cell dysfunction in NSCLC ***,blocking this pathway provides a potential therapy target in lung cancer.

关键词： lung cancer programmed death-1 tumor-infiltrating lymphocyte

Quantum support vector machine for multi classification

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Communications in Theoretical Physics 2024年第7期76卷 57-62页

作者： Li Xu Xiao-yu Zhang Ming Li Shu-qian shen College of Science China University of PetroleumQingdao 266580China

Classical machine learning algorithms seem to be totally incapable of processing tremendous data,while quantum machine learning algorithms could deal with big data unhurriedly and provide exponential acceleration over classical *** this paper,we propose two quantum support vector machine algorithms for multi *** is the quantum version of the directed acyclic graph support vector *** other one is to use the Grover search algorithm before measurement,which amplifies the amplitude of the phase storing of the classification *** k classification,the former provides quadratic reduction in computational complexity when *** latter accelerates the training speed significantly and more importantly,the classification result can be read out with a probability of at least 50%using only one *** conduct numerical simulations on two algorithms,and their classification success rates are 96%and 88.7%,respectively.

关键词： quantum support vector machine quantum feature mapping Grover search algorithm

Variational quantum algorithms for trace norms and their applications

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Communications in Theoretical Physics 2021年第10期73卷 90-96页

作者： sheng-Jie Li Jin-Min Liang Shu-qian shen Ming Li College of Science China University of Petroleum266580 QingdaoChina School of Mathematical Sciences Capital Normal University100048 BeijingChina

The trace norm of matrices plays an important role in quantum information and quantum computing. How to quantify it in today’s noisy intermediate scale quantum(NISQ) devices is a crucial task for information processing. In this paper, we present three variational quantum algorithms on NISQ devices to estimate the trace norms corresponding to different *** with the previous methods, our means greatly reduce the requirement for quantum resources. Numerical experiments are provided to illustrate the effectiveness of our algorithms.

关键词： quantum algorithm trace norm variational algorithm