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| 1 | Optimal guidance of extended trajectory shaping显示文摘To control missile's miss distance as well as terminal impact angle, by involving the timeto-go-nth power in the cost function, an extended optimal guidance law against a constant maneuvering target or a stationary target is proposed using the linear quadratic optimal control theory.An extended trajectory shaping guidance(ETSG) law is then proposed under the assumption that the missile-target relative velocity is constant and the line of sight angle is small. For a lag-free ETSG system, closed-form solutions for the missile's acceleration command are derived by the method of Schwartz inequality and linear simulations are performed to verify the closed-form results. Normalized adjoint systems for miss distance and terminal impact angle error are presented independently for stationary targets and constant maneuvering targets, respectively. Detailed discussions about the terminal misses and impact angle errors induced by terminal impact angle constraint, initial heading error, seeker zero position errors and target maneuvering, are performed. | Wang Hui Lin Defu Cheng Zhenxuan Wang Jiang | 2014 | Chinese Journal of Aeronautics2014，27，5： | 11 |
| 2 | Analysis and improvement of missile three-loop autopilots显示文摘The non-minimum phase feature of tail-controlled missile airframes is analyzed.Three selection strategies for desired performance indexes are presented.An acceleration autopilot design methodology based on output feedback and optimization is proposed.Performance and robustness comparisons between the two-loop and classical three-loop topologies are made.Attempts to improve the classical three-loop topology are discussed.Despite the same open-loop structure,the classical three-loop autopilot shows distinct characteristics from a two-loop autopilot with PI compensator.Both the two-loop and three-loop topologies can stabilize a static unstable missile.However, the finite actuator resource is the crucial factor dominating autopilot function. | Lin Defu Fan Junfang Qi Zaikang Mou Yu | 2009 | Journal of Systems Engineering and Electronics2009，20，4： | 10 |
| 3 | Development of the Array Transient Electromagnetic System and Its Experiments显示文摘Transient electromagnetic (TEM) technique plays a significant role in mineral exploration. To accommodate the complicated survey environments in the west part of China, we developed a portable array TEM equipment (ATEM-1), which was implemented based upon the idea to apply the GPS timing signal for the synchronization among transmitters and receivers. The structure of the system and its performance are discussed and the case study is also described. | Lin Jun Cheng Defu Liu Guoxing Duan Qingming Zhang Linhang Yu Shengbao | 2000 | Global Geology2000，5，1： | 3 |
| 4 | Control of static unstable airframes显示文摘The challenge and control problems of static unstable missiles are presented. The steady-state benefits of static instability are illustrated, while the corresponding control challenge is described both by the characteristic lag of airframe and the increment of necessary control usage. Control limitation led by unstable zero-pole pair is analyzed for preliminary design and evaluation. Linear control strategy is examined wherein two and three loop acceleration autopilots with different control usages are developed using an optimal control approach combined with frequency domain constraint. The weights selection and relation with system performance are detailed. Then the nonlinear backstepping recursive method is detailed to determine how well it is able to follow command and its engineering feasibility. The results show that a static unstable missile is controllable, while the actuator bandwidth is the crucial limited factor. There should be a compromise between overall performance and actuator payment. | Junfang Fan Defu Lin Zhong Su Qing Li | 2010 | Journal of Systems Engineering and Electronics2010，21，6： | 2 |
| 5 | Extended locglsearch algorithm based on nonlinear programming for two-di-mensional irregular strip packing problem显示文摘 | Leung S C H Lin Yangbin Zhang Defu | 2012 | Computers &Operations Research2012，39，3： | 1 |
| 6 | Temperature In- duced Denaturation of Collagen in Acidic Solution 显示文摘 | Changdao Mu Defu Li Wei Lin | 2007 | Biopolymers2007，86，： | 1 |
| 7 | Time-to-go weighted optimal trajectory shaping guidance law 显示文摘 | Wang Hui Lin Defu Cheng Zhenxuan | 2011 | Journal of Beifing Institute of Technology2011，20，3： | 1 |
| 8 | Extended local search algorithm based on nonlinear programming for two-dimensional irregular strip packing problem 显示文摘 | Stephen C H Leung Lin Yangbin Zhang Defu | 2012 | Computers & Operations Research2012，39，3： | 1 |
| 9 | Ultrasonic irradiation in the enzymatic extraction of collagen显示文摘 | Defu Li Changdao Mu Sumei Cai Wei Lin | 2009 | Ultrasonics - Sonochemistry2009，，5： | 1 |
| 10 | Impact time control guidance against maneuvering targets based on a nonlinear virtual relative model显示文摘Aiming at the problem of high-precision interception of air-maneuvering targets with impact time constraints,this paper proposes a novel guidance law based on a nonlinear virtual relative model in which the origin is attached to the target.In this way,the original maneuvering target is transformed into a stationary one.A polynomial function of the guidance command in the range domain with two unknown coefficients is introduced into the virtual model,one of the coefficients is determined to achieve the impact time constraint,and the other is determined to satisfy a newly defined virtual look angle constraint.For meeting the terminal constraints simultaneously,the guidance command can finally be obtained.The resulting solution is represented as a combination of proportional navigation guidance-like term which is aimed to meet the zero miss distance constraint,a bias term for impact time control by adjusting the length of the homing trajectory,and an additional term for target maneuvers.Numerous simulations demonstrate that the proposed law achieves an acceptable impact time error for various initial conditions against different types of maneuvering targets and shows more effective performance in comparison with those of other existing guidance laws. | Yuru BIN Hui WANG Defu LIN Yaning WANG Xin SUN | 2023 | Chinese Journal of Aeronautics2023，36，7： | 0 |
| 11 | SINGLET OXYGEN DETECTION DURING PHOTOSENSITIZATION显示文摘Singlet oxygen(^(1)O_(2))is a highly reactive oxygen species involved in numerous chemical and photochemical reactions in diferent biological systems and in particular,in photodynamic therapy(PDT).However,the quantifcation of^(1)O_(2) generation during in vitro and in vivo pho-tosensitization is still technically challenging.To address this problem,indirect and direct methods for^(1)O_(2)detection have been intensively studied.This review presents the available methods currently in use or under development for detecting and quantifying^(1)O_(2) generation during photosensitization.The advantages and limitations of each method will be presented.Moreover,the future trends in developing PDT-^(1)O_(2) dosimetry will be briefly discussed. | BUHONG LI HUIYUN LIN DEFU CHEN BRIAN C.WILSON YING GU | 2013 | Journal of Innovative Optical Health Sciences2013，6，1： | 0 |
| 12 | Editorial for the Special Issue on Unmanned Intelligent Cluster显示文摘Recent advances in networked cooperative autonomous sys-tems offer the potential to significantly improve system quality for a wide range of applications.Progress in embedded processor,sensor,communication,and networking technology in the last few decades has accelerated interest in networked cooperative autonomous systems,multirobot systems,and distributed sensor networks for applications such as manufacturing,logistics,pro-cess monitoring,enhanced situational awareness,plant safety,inspection,security,and rescue operations. | Jun Zhang Toshio Fukuda Defu Lin Florian Holzapfel | 2022 | Engineering2022，8，5： | 0 |
| 13 | UnIC: Towards Unmanned Intelligent Cluster and Its Integration into Society显示文摘Collaborative unmanned systems have emerged to meet our society’s wide-ranging grand challenges,with their advantages including high performance,efficiency,flexibility,and inherent resilience.Increasing levels of group/team autonomy have also been achieved due to the embodiment of artificial intelligence(AI).However,the current networked unmanned systems are primarily designed for and applicable to a narrow range of domain-specific missions,and do not have sufficient human-level intel-ligence and human needs fulfillment for the challenging missions in our lives.We propose in this paper a vision of human-centric networked unmanned systems:Unmanned Intelligent Cluster(UnIC).Within this vision,distributed unmanned systems and humans are connected via knowledge sharing and social awareness to achieve collaborative cognition.This paper details UnIC’s concept,sources of intelligence,and layered architecture,and reviews enabling technologies for achieving this vision.In addition to the technological aspects,the social acceptance issues are highlighted. | Fubiao Zhang Jing Yu Defu Lin Jun Zhang | 2022 | Engineering2022，8，5： | 0 |
| 14 | Research Status and Key Technologies of Geo-Electromagnetic Magnetic Induction Sensor显示文摘According to different applications,the performance parameters of the several Geo-Electromagnetic Magnetic Induction Sensors( GEMISs) which are the most representative in the world are compared. After discussing the several key technologies for improving the performance of GEMISs,the main conclusions are as follows: the application bandwidth can be expanded by adopting flux negative feedback( 1 m Hz-10 k Hz);'laminated'core structure is useful for suppressing eddy current loss; the effective permeability of the core has increased observably after adding flux concentrators to the two ends of the core; the chopper amplifier is a useful method to suppress 1/f noise for reducing the GEMIS's output noise; the indoor calibration scheme based on'long straight solenoid'proposed to obtain sensor sensitivity. Accordingly,the problem how to reduce the noise of GEMIS is urgent need to be solved,which will improve the performance of GEMIS. And there is plenty of work requires further study on parameters ' optimization of coil and core. In the future,miniaturization,intelligence and three-axis measurement are the development directions of GEMIS. | Yanzhang Wang Yunxia Wan Chen Chen Hongyu Shi Jun Lin Defu Cheng | 2017 | Journal of Harbin Institute of Technology(New Series)2017，24，4： | 0 |
| 15 | Effects of pulse width and repetition rate of pulsed laser on kinetics and production of singlet oxygen luminescence显示文摘Pulsed and continuous-wave(CW)lasers have been widely used as the light sources for photodynamic therapy(PDT)treatment.Singlet oxygen(^(1)O_(2))is known to be a major cytotoxic agent in type-II PDT and can be directly detected by its near-infrared luminescence at 1270 nm.As compared to CW laser excitation,the effiects of pulse width and repetition rate of pulsed laser on the kinetics and production of^(1)O_(2)luminescence were quantitatively studied during photosensitization of Rose Bengal.Significant di®erence in kinetics of^(1)O_(2)luminescence was found under the excitation with various pulse widths of nanosecond,microsecond and CW irradiation with power of 20mW.The peak intensity and duration of^(1)O_(2)production varied with the pulse widths for pulsed laser excitation,while the^(1)O_(2)was generated continuously and its production reached a steady state with CW excitation.However,no significant di®erence(P>0:05)in integral^(1)O_(2)production was observed.The results suggest that the PDT efficacy using pulsed laser may be identical to the CW laser with the same wavelength and the same average°uence rate below a threshold in solution. | Defu Chen Ying Wang Buhong Li Huiyun Lin Xuechun Lin Ying Gu | 2016 | Journal of Innovative Optical Health Sciences2016，9，6： | 0 |
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