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Multi-Frequency-Ranging Positioning Algorithm for 5G OFDM Communication Systems

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Chinese Journal of electronics 2023年第4期32卷 773-784页

作者： LI Wengang xu Yaqin ZHANG Chenmeng tian Yiheng liu Mohan HUANG Jun State key laboratory of Integrated Services Networks College of Communication EngineeringXidian University Electronic Countermeasures Academy National University of Defense Technology

The accurate determination of vehicle location is of great research significance, considering challenges such as the multipath environment and the absence of Global Navigation Satellite System(GNSS) signals. In this particular environment, vehicles equipped with 5G wireless communication devices can enhance their positioning accuracy by exchanging information with infrastructure(vehicle-to-infrastructure, V2I). Therefore,in this paper, we propose a multifrequency ranging method and positioning algorithm specifically designed for 5G orthogonal frequency division multiplexing(OFDM) communication systems. Our approach involves selecting specific subcarriers within the OFDM communication system for transmitting ranging frames and capturing delay observations. Importantly, this selection does not affect the functionality of other subcarriers used for regular communication. By utilizing dedicated subcarriers for ranging and positioning, we achieve accurate vehicle location without significantly impacting communication *** outline the method for selecting ranging subcarriers and describe the format of the ranging frame carried by these subcarriers. To evaluate the effectiveness of our system, we prove the Cramér-Rao lower bound of this ranging positioning system. The obtained ranging positioning accuracy meets the requirements for vehicle location applications. In our experimental simulations, we compare the performance of our system with other positioning methods, demonstrating its superiority. Additionally,we provide theoretical proofs and simulations that establish the relationship between ranging accuracy and channel parameters in a multipath environment. The simulation results indicate that, under the conditions of a 5 GHz frequency and a high signal-to-noise ratio, our system achieves a positioning accuracy of approximately 5 cm.

关键词： Wireless communication Base stations Global navigation satellite system 5G mobile communication OFDM Vehicle-to-infrastructure Simulation

Pulsar/CNS integrated navigation based on federated UKF

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Journal of Systems engineering and electronics 2010年第4期21卷 675-681页

作者： Jin liu Jie Ma Jinwen tian State key laboratory for Multi-spectral Information Processing Technologies Institue for Pattern Recognition and artifical Intelligence Huazhong University of Science and Technology Wuhan 430074 P. R. China

In order to improve the autonomous navigation capability of satellite,a pulsar/CNS（celestial navigation system） integrated navigation method based on federated unscented Kalman filter（UKF） is *** celestial navigation is a mature and stable navigation ***,its position determination performance is not satisfied due to the low accuracy of horizon *** pulsar navigation is a new navigation method,which can provide highly accurate range *** major drawback of single pulsar navigation is that the system is completely *** two methods are complementary to each other,the federated UKF is used here for fusing the navigation data from single pulsar navigation and *** to the traditional celestial navigation method and single pulsar navigation,the integrated navigation method can provide better navigation *** simulation results demonstrate the feasibility and effectiveness of the navigation method.

关键词： autonomous navigation celestial navigation system(CNS) pulsar federated unscented Kalman filter(UKF).

Extension of TOPSIS for fuzzy multi-attribute decision making problem based on experimental analysis

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Journal of Systems engineering and electronics 2010年第3期21卷 416-422页

作者： Min tian Yuanyuan He Sifeng liu College of Economics and Management Nanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China

This paper is concerned with a technique for order performance by similarity to ideal solution（TOPSIS） method for fuzzy multi-attribute decision making,in which the information about attribute weights is partly known and the attribute values take form of triangular fuzzy *** the fact that the triangular fuzzy TOPSIS results yielded by different distance measures are different from others,a comparative analysis of triangular fuzzy TOPSIS ranking from each distance measure is illustrated with discussion on standard *** applying the most reasonable distance,the deviation degrees between attribute values are measured.A linear programming model based on the maximal deviation of weighted attribute values is established to obtain the attribute ***,alternatives are ranked by using TOPSIS ***,a numerical example is given to show the feasibility and effectiveness of the method.

关键词： fuzzy multi-attribute decision making technique for order performance by similarity to ideal solution(TOPSIS) method triangular fuzzy number distance measure.

Cloud detection from visual band of satellite image based on variance of fractal dimension

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Journal of Systems engineering and electronics 2019年第3期30卷 485-491页

作者： tian Pingfang GUANG Qiang liu Xing School of Computer science and Technology Wuhan University of Science and Technology Wuhan 430065 China key laboratory of Intelligent Information Processing and Real-Time Industrial System in Hubei Province Wuhan 430065 China Institute of Big Data science and engineering Wuhan University of Science and Technology Wuhan 430065 China key laboratory of Rich-Media Knowledge Organization and Service of Digital Publishing Content National Press and Publication Administration Beijing 100038 China

Cover ratio of cloud is a very important factor which affects the quality of a satellite image, therefore cloud detection from satellite images is a necessary step in assessing the image quality. The study on cloud detection from the visual band of a satellite image is developed. Firstly, we consider the differences between the cloud and ground including high grey level, good continuity of grey level, area of cloud region, and the variance of local fractal dimension (VLFD) of the cloud region. A single cloud region detection method is proposed. Secondly, by introducing a reference satellite image and by comparing the variance in the dimensions corresponding to the reference and the tested images, a method that detects multiple cloud regions and determines whether or not the cloud exists in an image is described. By using several Ikonos images, the performance of the proposed method is demonstrated.

关键词： cloud detection visual image satellite image variance of local fractal dimension (VLFD)

A Point-of-Care Test System for Biochemical Blood Analysis Based on ADUC824

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稀有金属材料与工程 2006年第S3期 75-79页

作者： Hui Wang~(1,2) Qing tian~(1,2) Liying Jiang~(1,2) Chunxiu liu~(1,2) Zonghui Guo~(1,2) Xinxia Cai~1 (1.State key laboratory of Transducer Technology,Institute of electronics,Chinese Academy of science Chinese Academy of sciences,Beijing 100080,China) (2.Graduate School of Chinese Academy of sciences,Beijing 100080,China)

A point-of-care test system has been studied in this *** was used to determine substances in blood such as Hemoglobin (HB),Aspartate Aminotransferase (AST),Creatine Kinase (CK) and so *** on the principle of amperometric determination,the research on detecting weak current signals was carried *** the same time as to the weak signals (nA level),magnifying,sampling and processing the signals were also *** by ADUC824 and assisted by other units, every substance could be determined automatically and rapidly integrated with the corresponding *** the experiment, the minimum detectable current of the instrument (YT2005-1) is 0.2 *** regard to the 1 nA which the experiment demanded,it could be up to the *** the system can provide results in 180 s with a long term stability.

关键词： point-of-care test ADUC824 weak signals HB,AST and CK

人工智能在结直肠癌诊疗中的研究进展及前景展望

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中华胃肠外科杂志 2024年第1期27卷 15-23页

作者：魏炜何坤山胡振远刘振宇汤坚强田捷西安工程大学电子信息学院西安710048 中国科学院自动化研究所中国科学院分子影像重点实验室北京100190 国家癌症中心/国家肿瘤临床医学研究中心、中国医学科学院北京协和医学院肿瘤医院结直肠外科北京100021 北京航空航天大学北京市大数据精准医疗高精尖创新中心北京100191

结直肠癌是全球最常见的恶性肿瘤之一, 由于患者对标准治疗方案存在异质性的治疗反应及预后, 其个性化诊疗策略一直是备受关注的研究热点。近年来, 随着人工智能(AI)技术在医疗领域的迅猛发展, AI在辅助结直肠癌的术前、术中、术后各阶... 详细信息

结直肠癌是全球最常见的恶性肿瘤之一, 由于患者对标准治疗方案存在异质性的治疗反应及预后, 其个性化诊疗策略一直是备受关注的研究热点。近年来, 随着人工智能(AI)技术在医疗领域的迅猛发展, AI在辅助结直肠癌的术前、术中、术后各阶段诊疗方案决策方面均涌现出大量阶段性研究成果, 展现出了巨大的应用潜力, 为结直肠癌患者的个体化评估和辅助诊疗提供了全新且高效的解决方案。未来, AI系统可能会进一步向多模态、多组学、实时化方向发展。本文旨在探讨AI在结直肠癌诊疗多个方面的辅助应用研究现状, 并对AI技术在未来结直肠癌个性化诊疗中可能带来的创新和面临的挑战予以展望。

关键词：人工智能结直肠肿瘤手术导航医学影像精准医学

Flight control for a flexible air-breathing hypersonic vehicle based on quasi-continuous high-order sliding mode

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Journal of Systems engineering and electronics 2013年第2期24卷 288-295页

作者： Jie Wang Qun Zong Bailing tian Helong liu School of Electrical engineering and Automation Tianjin University

The focus of this paper is on control design and simulation for the longitudinal model of a flexible air-breathing hypersonic vehicle（FAHV）.The model of interest includes flexibility effects and intricate couplings between the engine dynamics and flight *** overcome the analytical intractability of this model,a nominal control-oriented model is constructed for the purpose of feedback control design in the first ***,the multi-input multi-output（MIMO） quasi-continuous high-order sliding mode（HOSM） controller is proposed to track step changes in velocity and altitude,which is based on full state *** simulation results are presented to verify the effectiveness of the proposed control strategy.

关键词： flexible air-breathing hypersonic vehicle nonlinear robust controller high order sliding mode control output tracking control

Low complexity reconfigurable architecture for the 5/3 and 9/7 discrete wavelet transform

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Journal of Systems engineering and electronics 2006年第2期17卷 303-308页

作者： Xiong Cheng yi tian Jinwen liu Jian Coll. of Electronic Information engineering South Center Univ. for Nationalities Wuhan 430074 P.R. China Inst. of Pattern Recognition & Artificial Intelligence Key Lab. of Education Ministry for Image Processing and Intelligent Control Huazhong Univ. of Science & Technology Wuhan 430074 P.R. China

Efficient reconfigurable VLSI architecture for 1-D 5/3 and 9/7 wavelet transforms adopted in JPEG2000 proposal, based on lifting scheme is proposed. The embedded decimation technique based on fold and time multiplexing, as well as embedded boundary data extension technique, is adopted to optimize the design of the architecture. These reduce significantly the required numbers of the multipliers, adders and registers, as well as the amount of accessing external memory, and lead to decrease efficiently the hardware cost and power consumption of the design. The architecture is designed to generate an output per clock cycle, and the detailed component and the approximation of the input signal are available alternately. Experimental simulation and comparison results are presented, which demonstrate that the proposed architecture has lower hardware complexity, thus it is adapted for embedded applications. The presented architecture is simple, regular and scalable, and well suited for VLSI implementation.

关键词： VLSI discrete wavelet transform lifting scheme embedded decimation reeonfigurable.

Atomic origin of the traps in memristive interface

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Nano Research 2017年第6期10卷 1924-1931页

作者： Ye tian Lida Pan Chuan Fei Guo Qian liu CAS Center of Excellence for Nanoscience CAS Key Laboratory of Nanosystem and Hierarchical Fabrication National Center for Nanoscience and Technology No. 11 Beiyitiao Zhongguancun Beijing 100190 China School of Communication and electronics engineering Hunan City University Yiyang 413000 China department of Physics and Astronomy Vanderbilt University Nashville TN 37235 USA Institute of Physics Chinese Academy of Sciences Beijing 100190 China Photonics Research Group Department of Information Technology Ghent University-IMEC Ghent B-9000 Belgium department of Materials science and engineering South University of Science and Technology of China Shenzhen 518055 China

In recent years, trap-related interfacial transport phenomena have received great attention owing to their potential applications in resistive switching devices and photo detectors. Not long ago, one new type of memristive interface that is composed of F-doped SnO2 and Bi2S3 nano-network layers has demonstrated a bivariate-continuous-tunable resistance with a swift response comparable to the one in neuron synapses and with a brain-like memorizing capability. However, the resistive mechanism is still not clearly understood because of lack of evidence, and the limited improvement in the development of the interfacial device. By combining I-V characterization, electron energy-loss spectroscopy, and first- principle calculation, we studied in detail the macro/micro features of the memristive interface using experimental and theoretical methods, and confirmed that its atomic origin is attributed to the traps induced by O-doping. This implies that impurity-doping might be an effective strategy for improving switching features and building new interfacial memristors.

关键词： memristance interface trap state first principle calculation