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Hierarchical Feature-Based Detection Method for SAR Targets Under Complex Environment

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Chinese Journal of Electronics 2017年第3期26卷 647-653页

作者： GAO Fei MA Fei luo Xiling WANG Jun SUN Jinping School of Electronic and Information Engineering Beihang University

A reliable target detection method for Synthetic aperture radar(SAR)images is needed urgently with the wide application of SAR *** performance of conventional detection algorithms,such as Constant false alarm rate(CFAR),degrade significantly in low SCR or complex regions while the Human visual system(HVS)can identify targets of interest without knowing characteristics of the background even in complicated *** combination of HVS with the SAR-ATR system may effectively achieve real-time multi-target detection in complex occlusion scenes.A new effective target detection algorithm is put forward using hierarchical characteristics of *** by different roles of the retina and visual cortex in the HVS,this detection algorithm is divided into coarse detection and fine detection *** kinds of features based on the correlation between target features and suspicious targets,namely overall feature and refined feature,are used in these two stages respectively to extract real *** results verify its correctness and effectiveness in complex environment.

关键词： Synthetic aperture radar(SAR) Targets detection Human visual system(HVS) Complex background Hierarchical model and X(HMAX)

Quantification of ventilation enhancement using the Eye CAN roof support

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International Journal of Mining Science and Technology 2017年第1期27卷 153-158页

作者： Shook Michael T Sindelar Mark F, Jiang Hua luo Yi Burrell Mining Products Inc.New KensingtonPA 15068USA Department of Mining Engineering West Virginia UniversityMorgantownWV 26506USA

Convergence of roof and floor in underground mine openings is a common occurrence. This convergence not only adversely affects the ability of workers, equipment and supplies to travel through the mine, it also reduces the effectiveness of the mine ventilation system, which is essential for the dilution of methane gas and airborne respirable dust. While installing secondary standing supports to control floor and roof convergence, such supports, by nature, partially obstruct a portion of the airway. These added obstructions inhibit the ability of the ventilation system to operate as efficiently as it could by increasing the resistance in and reducing the cross-sectional area of the airway. This study introduces and demonstrates the benefits of The Eye CAN^(TM) standing roof support, which controls floor and roof convergence and is less obstructive to air flow than conventional wooden cribs. Laboratory findings show that the normal resistance of a supported lined airway is reduced by using this new product from Burrell Mining Products, Inc., while providing the same roof support characteristics of an established product—The CANò. Load vs. displacement curves generated from laboratory tests demonstrated that this new product behaves with the same roof support characteristics as others in The CAN product family. Ventilation data gathered from a simulated mine entry was then used for computational fluid dynamics(CFD) *** CFD analysis showed an improvement with The Eye CAN vs. other accepted forms of standing roof support. This proof-of-concept study suggests that, when using this new product made by Burrell Mining Products, Inc., not only will the convergence from the roof and floor be controlled, but airway resistance will also be reduced.

关键词： Standing roof support CAN Ventilation Load-displacement Eye CAN

Assimilating Doppler radar observations with an ensemble Kalman filter for convection-permitting prediction of convective development in a heavy rainfall event during the pre-summer rainy season of South China

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Science China Earth Sciences 2017年第10期60卷 1866-1885页

作者： BAO XingHua luo YaLi SUN JiaXiang MENG ZhiYong YUE Jian State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology Nanjing 210044 China CAAC East China Regional Air Traffic Administration Shanghai 200335 China Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic Sciences School of Physics Peking University Beijing 100871 China National Meteorological Center China Meteorological Administration Beijing 100081 China

This study examines the effectiveness of an ensemble Kalman filter based on the weather research and forecasting model to assimilate Doppler-radar radial-velocity observations for convection-permitting prediction of convection evolution in a high-impact heavy-rainfall event over coastal areas of South China during the pre-summer rainy season. An ensemble of 40 deterministic forecast experiments(40 DADF) with data assimilation(DA) is conducted, in which the DA starts at the same time but lasts for different time spans(up to 2 h) and with different time intervals of 6, 12, 24, and 30 min. The reference experiment is conducted without DA(NODA).To show more clearly the impact of radar DA on mesoscale convective system(MCS)forecasts, two sets of 60-member ensemble experiments(NODA EF and exp37 EF) are performed using the same 60-member perturbed-ensemble initial fields but with the radar DA being conducted every 6 min in the exp37 EF experiments from 0200 to0400 BST. It is found that the DA experiments generally improve the convection prediction. The 40 DADF experiments can forecast a heavy-rain-producing MCS over land and an MCS over the ocean with high probability, despite slight displacement errors. The exp37 EF improves the probability forecast of inland and offshore MCSs more than does NODA EF. Compared with the experiments using the longer DA time intervals, assimilating the radial-velocity observations at 6-min intervals tends to produce better forecasts. The experiment with the longest DA time span and shortest time interval shows the best ***, a shorter DA time interval(e.g., 12 min) or a longer DA time span does not always help. The experiment with the shortest DA time interval and maximum DA window shows the best performance, as it corrects errors in the simulated convection evolution over both the inland and offshore areas. An improved representation of the initial state leads to dynamic and thermodynamic conditions that are more conducive to

关键词： Radial velocity EnKF Heavy rainfall forecast Pre-summer rainy season South China

Coal and gas outburst dynamic system

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International Journal of Mining Science and Technology 2017年第1期27卷 49-55页

作者： Fan Chaojun Li Sheng luo Mingkun Du Wenzhang Yang Zhenhua College of Mining Engineering Liaoning Technical UniversityFuxin 123000China State Key Laboratory for Geo Mechanics and Deep Underground Engineering China University of Mining&Technology Xuzhou 221116China State Key Laboratory of Coal Resources and Safe Mining China University of Mining&TechnologyXuzhou 221116China

Coal and gas outburst is an extremely complex dynamic disaster in coal mine production process which will damage casualties and equipment facilities, and disorder the ventilation system by suddenly ejecting a great amount of coal and gas into roadway or working face. This paper analyzed the interaction among the three essential elements of coal and gas outburst dynamic system. A stress-seepage-damage coupling model was established which can be used to simulate the evolution of the dynamical system, and then the size scale of coal and gas outburst dynamical system was investigated. Results show that the dynam- ical system is consisted of three essential elements, coal-gas medium （material basis）, geology dynamic environment （internal motivation） and mining disturbance （external motivation）. On the case of CI 3 coal seam in Panyi Mine, the dynamical system exists in the range of 8-12 m in front of advancing face. The size scale will be larger where there are large geologic structures. This research plays an important guid- ing role for developing measures of coal and gas outburst prediction and prevention.

关键词： Coal and gas outburst Dynamic system Coal-gas mediumlGeology dynamic environment Mining disturbanceStress-seepage-damage coupling model

Synthesis of refrigeration system based on generalized disjunctive programming model

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Chinese Journal of Chemical Engineering 2018年第8期26卷 1613-1620页

作者： Danlei Chen Xue Ma Yiqing luo Yingjie Ma Xigang Yuan School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China State Key Laboratory of Chemical Enineering Tianjin University Tianjin 300072China

Refrigeration system holds an important role in process industries. The optimal synthesis cannot only reduce the energy consumption, but also save the production costs. In this study, a general methodology is developed for the optimal design of refrigeration cycle and heat exchanger network(HEN) simultaneously. Taking the heat integration between the external heat sources/sinks and the refrigeration cycle into consideration, a superstructure with sub-coolers is developed. Through defining logical variables that indicate the relative temperature positions of refrigerant streams after sub-coolers, the synthesis is formulated as a Generalized Disjunctive Programming(GDP) problem based on LP transshipment model, with the target of minimizing the total compressor shaft work in the refrigeration system. The GDP model is then reformulated as a Mixed Integer Nonlinear Programming(MINLP) problem with the aid of binary variables and Big-M Constraint Method. The efficacy of the process synthesis model is demonstrated by a case study of ethylene refrigeration system. The result shows that the optimization can significantly reduce the exergy loss as well as the total compression shaft work.

关键词： Refrigeration system Process synthesis Generalized Disjunctive Programming (GDP) Mixed Integer Nonlinear Programming (MINLP)

Home location inference from sparse and noisy data:models and applications

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Frontiers of Information Technology & Electronic Engineering 2016年第5期17卷 389-402页

作者： Tian-ran HU Jie-bo luo Henry KAUTZ Adam SADILEK Computer Science Department University of Rochester

Accurate home location is increasingly important for urban computing. Existing methods either rely on continuous(and expensive) Global Positioning System(GPS) data or suffer from poor accuracy. In particular, the sparse and noisy nature of social media data poses serious challenges in pinpointing where people live at scale. We revisit this research topic and infer home location within 100 m×100 m squares at 70% accuracy for 76% and 71%of active users in New York City and the Bay Area, respectively. To the best of our knowledge, this is the first time home location has been detected at such a fine granularity using sparse and noisy data. Since people spend a large portion of their time at home, our model enables novel applications. As an example, we focus on modeling people's health at scale by linking their home locations with publicly available statistics, such as education disparity. Results in multiple geographic regions demonstrate both the effectiveness and added value of our home localization method and reveal insights that eluded earlier studies. In addition, we are able to discover the real buzz in the communities where people live.

关键词： Home location Mobility patterns Healthcare

An Active De-anonymizing Attack Against Tor Web Traffic

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Tsinghua Science and Technology 2017年第6期22卷 702-713页

作者： Ming Yang Xiaodan Gu Zhen Ling Changxin Yin Junzhou luo School of Computer Science and Engineering Southeast University Nanjing 211189 China

Tor is pervasively used to conceal target websites that users are visiting. A de-anonymization technique against Tor, referred to as website fingerprinting attack, aims to infer the websites accessed by Tor clients by passively analyzing the patterns of encrypted traffic at the Tor client side. However, HTTP pipeline and Tor circuit multiplexing techniques can affect the accuracy of the attack by mixing the traffic that carries web objects in a single TCP connection. In this paper, we propose a novel active website fingerprinting attack by identifying and delaying the HTTP requests at the first hop Tor node. Then, we can separate the traffic that carries distinct web objects to derive a more distinguishable traffic pattern. To fulfill this goal, two algorithms based on statistical analysis and objective function optimization are proposed to construct a general packet delay scheme. We evaluate our active attack against Tor in empirical experiments and obtain the highest accuracy of 98.64%, compared with 85.95% of passive attack. We also perform experiments in the open-world scenario. When the parameter k of k-NN classifier is set to 5, then we can obtain a true positive rate of 90.96% with a false positive rate of 3.9%.

关键词： traffic analysis active website fingerprinting anonymous communication Tor

Intra-Organizational Social Media and Employee Idea Generation:Analysis based on the Spanning-Relevance Framework

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Journal of Systems Science and Systems Engineering 2022年第6期31卷 649-676页

作者： Benjiang Lu Xunhua Gu Nianlong luo Xueli Wang Guoqing Chen School of Business Nanjing UniversityNanjing 210093China School of Economics and Management Tsinghua UniversityBeijing 10084China Information Technology Center Tsinghua University Beijing 100084China China Retail Research Center School of Economics and ManagementTsinghua UniversityBeijing 100084China

Intra-organizational social media platforms are expected to help build a flexible corporate stage that facilitates employees'communication and leverages creative idea ***,whether and how these systems can expedite the creativity of employees remains *** paper attempts to address the impacts of employees'social relationships on intra-organizational social media on their idea generation quantity and *** upon the extant literature in the fields of information systems and organizational behavior,a theoretical model is postulated on the basis of analyzing the attributes of social ties and exchanged information content in light of a two-dimensional framework that juxtaposes boundary spanning and work *** model is empirically tested using data obtained from two internal application systems of a large telecommunications *** results validate that employees'online social relationships with different attributes are discriminably associated with their group identification and proactive ***,proactive creativity and group identification both show the positive impacts on idea generation quantity,whereas only proactive creativity has a significant positive impact on idea generation *** findings contribute to the literature on intra-organizational social media and employee idea generation,by uncovering the links among employees'online social relationships,mental processes,and idea generation.

关键词： Intra-organizational social media online social relationship idea generation group identification proactivecreativity

Cloud-based smartphone-assisted chemiluminescent assay for rapid screening of electroactive bacteria

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Science China(Technological Sciences) 2023年第3期66卷 743-750页

作者： WEN JunLin HE DaiGui luo SongQing ZHOU ShunGui YUAN Yong Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control School of Environmental Science and EngineeringInstitute of Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China College of Artificial Intelligence Guangdong Mechanical&Electrical PolytechnicGuangzhou 510550China Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation College of Resources and EnvironmentFujian Agriculture and Forestry UniversityFuzhou 350002China

Electroactive bacteria(EAB)can transfer electrons to exocellular solid acceptors and have widespread applications in the fields of pollutant degradation,biosynthesis,and hydrogen *** EAB screening methods can precisely measure the bacterial extracellular electron transfer ability,but they suffer from time-consuming and labor-intensive *** chemiluminescence technique is effective for the rapid detection of hemoglobin but has not been applied for EAB ***,we utilized a chemiluminescent assay to identify EAB through a multiheme c-type cytochrome(c-Cyt)triggered chemiluminescent *** multiheme c-Cyts-triggered chemiluminescence was conveniently determined by taking photographs with commercial smartphones and cloud-based *** acquired image signal shows a significant and linear relationship with the bacterial *** results of the chemiluminescence intensity triggered by different bacterial species with the proposed method are strongly associated with those of the microplate reading method(Pearson’s r of 0.9795;P<0.01)and dissimilatory Fe(Ⅲ)reduction method(Pearson’s r of 0.9628;P<0.01).Furthermore,this cloud-based and smartphone-assisted chemiluminescent assay is instrument-free and easy to operate,and results can be obtained within 2 *** findings demonstrate that the proposed method can effectively detect ***,it will be an alternative approach for EAB screening and can have promising applications in microbiology,environmental science,and bioenergy.

关键词： electroactive bacteria c-type cytochrome chemiluminescence cloud computing smartphone