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Biomedical and Environmental Sciences 2021年第4期34卷 265-271页

作者： guo Jian guo kong Qi LIU Ce KANG Tai Sheng QIN Chuan NHC Key Laboratory of Human Disease Comparative Medicine Institute of Laboratory Animal SciencesCAMS&PUMCBeijing 100021China Key Laboratory of Human Diseases Animal Model State Administration of Traditional Chinese MedicineBeijing 100021China Department of Infectious Disease Beijing Chuiyangliu Hospital affiliated to Tsinghua UniversityBeijing 100022China

Objective Airborne microbial communities include a significant number of uncultured and poorly characterized *** effective method currently exists to evaluate the health risks of such complex bacterial populations,particularly for *** We developed a method to evaluate risks from airborne microorganisms,guided by the principle that closer evolutionary relationships reflect similar biological characteristics,and thus used16 S rDNA sequences of 10 common pneumonia-related bacterial *** calculated a risk of breath-related(Rbr)index of airborne bacterial communities and verified effectiveness with artificial flora and a clinical *** We suggested applying Rbr80 to evaluate the health risks of airborne bacterial communities that comprise 80% of dominant operational taxonomic units(OTUs).The feasibility of Rbr80 was confirmed by artificial flora and by pneumonia data from a hospital.A high Rbr80 value indicated a high risk of pneumonia from airborne bacterial *** Rbr80 is an effective index to evaluate the pneumonia-associated risk from airborne *** of Rbr80 greater than 15.40 are considered high risk.

关键词： Airborne bacteria The risk of breath related index(Rbr) Pneumonia Health risk

Recursive Dictionary-Based Simultaneous Orthogonal Matching Pursuit for Sparse Unmixing of Hyperspectral Data

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Transactions of Nanjing University of Aeronautics and Astronautics 2017年第4期34卷 456-464页

作者： kong Fanqiang guo Wenjun Shen Qiu Wang Dandan College of Astronautics Nanjing University of Aeronautics and Astronautics

The sparse unmixing problem of greedy algorithms still remains a great challenge at finding an optimal subset of endmembers for the observed data from the spectral library,due to the usually high correlation of the spectral *** such circumstances,a novel greedy algorithm for sparse unmixing of hyperspectral data is presented,termed the recursive dictionary-based simultaneous orthogonal matching pursuit(RD-SOMP).The algorithm adopts a block-processing strategy to divide the whole hyperspectral image into several *** each iteration of the block,the spectral library is projected into the orthogonal subspace and renormalized,which can reduce the correlation of the spectral *** RD-SOMP selects a new endmember with the maximum correlation between the current residual and the orthogonal subspace of the spectral *** endmembers picked in all the blocks are associated as the endmember sets of the whole hyperspectral ***,the abundances are estimated using the whole hyperspectral data with the obtained endmember *** can be proved that RD-SOMP can recover the optimal endmembers from the spectral library under certain *** results demonstrate that the RD-SOMP algorithm outperforms the other algorithms,with a better spectral unmixing accuracy.

关键词： hyperspectral unmixing greedy algorithm simultaneous sparse representation sparse unmixing

A Survivability Routing Mechanism in SDN Enabled Wireless Mesh Networks:Design and Evaluation

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China Communications 2016年第7期13卷 32-38页

作者： Yuhuai Peng Xiaoxue Gong Lei guo Dezhi kong School of Computer Science and Engineering Northeastern University

In software-defined networking,the separation of control plane from forwarding plane introduces new challenges to network *** paper proposes a fault-tolerant routing mechanism to improve survivability by converting the survivability problem into two sub-problems:constructing an elastic-aware routing tree and controller *** on the shortest path tree,this scheme continuously attempts to prune the routing tree to enhance network *** a certain number of iterations,elastic-aware routing continues to improve network resiliency by increasing the number of edges in this *** results demonstrate this fault-tolerant mechanism performs better than the traditional method in terms of the number of protected nodes and network fragility indicator.

关键词： fault-tolerant routing controller selection software defined networking(SDN)

Sediment transportation and bed morphology reshaping in Yellow River Delta

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Science China(Technological Sciences) 2009年第11期52卷 3382-3390页

作者： kong QingRong JIANG ChunBo QIN JunJie guo Bin State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijing 100084China

The Yellow River Delta supports the ecological function as a typical estuarine foreshore wetland. The wetland area is changing greatly every year because of sediment deposition and erosion, which influences the wetland function tremendously. Application of environmental fluid dynamics code (EFDC) to the Yellow River Delta is on the basis of the mobile bed dynamic model and wetting-drying process. Careful calibration is carried out for the numerical model which is set up for the Yellow River Delta, the sediment transport process of the model is compatible to the Yellow River situation. The simulated bed elevation by considering the sediment deposition in the Mouth is particularly focused on, the numerical results are in agreement with the measured bed morphology within 1992 2000. Simulation in this paper indicates that most of the sediment deposited just out of the Mouth which makes the mouth move forward into the sea 2.5 km per year. This paper presents good results in simulation of varying sediment deposition and provides further methods to predict the future morphology and area of the Yellow River Delta.

关键词： sediment morphology environmental fluid dynamics code (EFDC) Yellow River Delta

Initial virtual flight test for a dynamically similar aircraft model with control augmentation system

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Chinese Journal of Aeronautics 2017年第2期30卷 602-610页

作者： guo Linliang Zhu Minghong Nie Bowen kong Peng Zhong Chengwen School of Aeronautics Northwestern Polytechnical University Low Speed Aerodynamics Institute China Aerodynamics Research and Development Center

To satisfy the validation requirements of flight control law for advanced aircraft,a wind tunnel based virtual flight testing has been implemented in a low speed wind tunnel.A 3-degree-offreedom gimbal,ventrally installed in the model,was used in conjunction with an actively controlled dynamically similar model of aircraft,which was equipped with the inertial measurement unit,attitude and heading reference system,embedded computer and *** model,which could be rotated around its center of gravity freely by the aerodynamic moments,together with the flow field,operator and real time control system made up the closed-loop testing *** model is statically unstable in longitudinal direction,and it can fly stably in wind tunnel with the function of control augmentation of the flight control *** experimental results indicate that the model responds well to the operator＇s *** response of the model in the tests shows reasonable agreement with the simulation *** difference of response of angle of attack is less than 0.5°.The effect of stability augmentation and attitude control law was validated in the test,meanwhile the feasibility of virtual flight test technique treated as preliminary evaluation tool for advanced flight vehicle configuration research was also verified.

关键词： 3-degree-of-freedom gimbal Dynamic test Flight dynamics simulation Flight control system Real time Wind tunnel

Single track and single layer formation in selective laser melting of niobium solid solution alloy

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Chinese Journal of Aeronautics 2018年第4期31卷 860-866页

作者： Yueling guo Lina JIA Bin kong Na WANG Hu ZHANG School of Materials Science and Engineering Beihang University

Selective laser melting（SLM） was employed to fabricate Nb-37 Ti-13 Cr-2 Al-1 Si（at%）alloy, using pre-alloyed powders prepared by plasma rotating electrode processing（PREP）. A series of single tracks and single layers under different processing parameters was manufactured to evaluate the processing feasibility by SLM, including laser power, scanning speed, and hatch *** showed that continuous single tracks could be fabricated using proper laser powers and scanning velocities. Both the width of a single track and its penetration depth into a substrate increased with an increase of the linear laser beam energy density（LED）, i.e., an increase of the laser power and a decrease of the scanning speed. Nb, Ti, Si, Cr, and Al elements distributed heterogeneously over the melt pool in the form of swirl-like patterns. An excess of the hatch distance was not able to interconnect neighboring tracks. Under improper processing parameters, a balling phenomenon occurred, but could be eliminated with an increased LED. This work testified the SLMprocessing feasibility of Nb-based alloy and promoted the application of SLM to the manufacture of niobium-based alloys.

关键词： Additive manufacturing Melt pool Niobium alloy Powder metallurgy Selective laser melting

Stochastic regression and its application to hedging in finance

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Science China Mathematics 2009年第6期52卷 1365-1372页

作者： JING BingYi kong XinBing LIU zhi ZHANG Bo Department of Mathematics Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina School of Statistics Renmin University of ChinaBeijing 100072China

In this paper we investigate how to employ stochastic regression to hedge risks in finance,where the risk of a security is measured by its quadratic variation *** and Zhang used this technique to demonstrate how to reduce the risk of a given security by introducing another *** this paper,we investigate how to further reduce the remaining unhedgable risk by adding more hedging *** practical guidelines on how to choose those hedging securities in practice is also given.

关键词： risks hedging semimartingale Ito process

Adult duodenal intussusception with horizontal adenoma: A rare case report

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World Journal of Clinical Cases 2020年第15期8卷 3314-3319页

作者： Kun-Peng Wang Hao Jiang Can kong Lie-zhi Wang guo-Yu Wang Jing-Gang Mo Chong Jin Department of General Surgery Taizhou Central Hospital(Taizhou University Hospital)Taizhou 318000Zhejiang ProvinceChina Department of Radiology Taizhou Central Hospital(Taizhou University Hospital)Taizhou 318000Zhejiang ProvinceChina

BACKGROUND Adult duodenal intussusception rarely occurs,and the majority of duodenal adenomas are located in the descending part of the ***,adenomas in the horizontal part of the duodenum presenting as duodenal intussusception in adults are extremely *** SUMMARY A 36-year-old man complained of abdominal pain for 13 *** analysis showed *** resonance cholangiopancreatography and computed tomography revealed a tumor in the horizontal part of the duodenum as the main finding,leading to duodeno-duodenal *** obvious abnormalities were found on endoscopy or upper gastrointestinal *** was diagnosed with duodenal intussusception secondary to duodenal *** showed duodeno-duodenal intussusception and a tumor in the horizontal part of the duodenum near the ascending *** pathology revealed tubular-villous adenoma with low-grade glandular intraepithelial neoplasia(local high-grade intraepithelial neoplasia).He was discharged without *** This case highlights that rational use of computed tomography,magnetic resonance cholangiopancreatography,endoscopy and upper gastrointestinal radiography for preoperative diagnosis and timely surgery is an effective strategy for the treatment of adult duodenal intussusception with duodenal masses.

关键词： Adult duodenal intussusception Duodenal adenoma Horizontal part of the duodenum Intestinal obstruction Case report

A machine learning approach to query generation in plagiarism source retrieval

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Frontiers of Information Technology & Electronic Engineering 2017年第10期18卷 1556-1572页

作者： Lei-lei kong zhi-mao LU Hao-liang QI Zhong-yuan HAN College of Information and Communication Engineering Harbin Engineering University Harbin 150001 China School of Computer Science and Technology Heilongjiang Institute of Technology Harbin 150050 China State Key Laboratory of Digital Publishing Technology Beijing 100871 China

Plagiarism source retrieval is the core task of plagiarism detection. It has become the standard for plagiarism detection to use the queries extracted from suspicious documents to retrieve the plagiarism sources. Generating queries from a suspicious document is one of the most important steps in plagiarism source retrieval. Heuristic-based query generation methods are widely used in the current research. Each heuristic-based method has its own advantages, and no one statistically outperforms the others on all suspicious document segments when generating queries for source retrieval. Further improvements on heuristic methods for source retrieval rely mainly on the experience of experts. This leads to difficulties in putting forward new heuristic methods that can overcome the shortcomings of the existing ones. This paper paves the way for a new statistical machine learning approach to select the best queries from the candidates. The statistical machine learning approach to query generation for source retrieval is formulated as a ranking framework. Specifically, it aims to achieve the optimal source retrieval performance for each suspicious document segment. The proposed method exploits learning to rank to generate queries from the candidates. To our knowledge, our work is the first research to apply machine learning methods to resolve the problem of query generation for source retrieval. To solve the essential problem of an absence of training data for learning to rank, the building of training samples for source retrieval is also conducted. We rigorously evaluate various aspects of the proposed method on the publicly available PAN source retrieval corpus. With respect to the established baselines, the experimental results show that applying our proposed query generation method based on machine learning yields statistically significant improvements over baselines in source retrieval effectiveness.

关键词： Plagiarism detection Source retrieval Query generation Machine learning Learning to rank

A Study on Pollen Allergens in China

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Biomedical and Environmental Sciences 2010年第4期23卷 319-322页

作者： zhi-GANG LIU JUAN-JUAN SONG XIAO-LI kong State Key Laboratory of Allergic Respiratory Diseases School of Medicine Shenzhen University Shenzhen 518060 Guangdong China

Objective Allergic disease caused by airborne pollen is a major health problem in China. Intensive study on pollen allergens can be of great help for preventing and treating pollinosis. Four aspects of the study on pollen allergens in China including major allergic pollen in our country, analysis and purification of pollen allergen composition, recombinant pollen allergens and clinical application of pollen allergens are described in this paper.

关键词： Airborne pollen Allergens Clinical application Pollinosis Recombinant allergens