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A Spectrum Access Method based on Capacity Utility Maximization for Cognitive Mesh Networks

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A Spectrum Access Method based on Capacity Utility Maximizat...

Methanogenic community structure in simultaneous methanogenesis and denitrification granular sludge

第25届中国控制与决策会议

作者： zhao juanjuan zhao Peikun Department of Basic Science Baoding Vocational and Technical College

ISBN: (纸本)9781467355339

This paper proposes a spectrum access method based on the capacity utility maximization in wireless cognitive mesh networks. By taking into account the inactivity probability of the primary users, the spectrum sensing time, the probability of false alarm and the channel usage of the surrounding secondary users, a capacity utility function is formed. Through maximizing the capacity utility function, the optimal channel allocation method is proposed. In addition, the channel switching of secondary users is novel designed by lowering the transmitting power in the duration of finding new optimal channel. The simulation results show that, the proposed method obtains a good performance with the system throughput and the average end-to-end delay.

关键词： cognitive mesh networks spectrum access capacity utility channel switching

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Frontiers of Environmental Science & Engineering 2018年第4期12卷 99-107页

作者： Yujiao Sun juanjuan zhao Lili Chen Yueqiao Liu Jiane Zuo College of Water Science Beijing Normal University Beijing 100875 China School of Environment Tsinghua University Beijing 100084 China Envbonmental Engineering Department North China Institute of Science and Tectmology Beijing 101601 China

A laboratory scale up-flow anaerobic sludge bed （UASB） bioreactor ted with synthetic wastewater was operated with simultaneous methanogenesis and denitrification （SMD） granules for 235 days with a gradient decrease of C/N. Molecular cloning, qRT-PCR and T-RFLP were applied to study tile methanogenic community structures in SMD granules and their changes in response to changing influent C/N. The results indicate that when C/N was 20：1, the methane production rate was tastest, and Methanosaetaceae and Methanobacteriaceae were the primary methanogens within tile Archaea. The richness and evenness of methanogenic bacteria was best with the highest T-RFLP diversity index of 1.627 in the six granular sludge samples. When C/N was reduced from 20：1 to 5：1, tbe methanogenic activity of SMD granules decreased gradually, and the relative quantities of methanogens decreased from 36.5% to 10.9%. The abundance of Methanosaetaceae in Archaea increased from 64.5% to 84.2%, while that of Methanobacteriaceae decreased from 18.6% to 11.8%, and the richness and evenness of methanogens decreased along with the T-RFLP diversity index to 1.155, suggesting that the community structure reflected the succession to an unstable condition represented by high nitrate concentrations.

关键词： Simultaneous methanogenesis and denitrifi-cation (SMD) Methanogens Community structure Diversity index Granular sludge

An automated pulmonary parenchyma segmentation method based on an improved region growing algorithm in PET-CT imaging

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Frontiers of Computer Science 2016年第1期10卷 189-200页

作者： juanjuan zhao Guohua JI Xiaohong HAN Yan QIANG Xiaolei LIAO College of Computer Science and Technology Taiyuan University of Technology Taiyuan 030024 China Key Laboratory of Advanced Transducers and Intelligent Control Systems Taiyuan University of Technology Taiyuan 030024 China

To address the incomplete problem in pulmonary parenchyma segmentation based on the traditional methods, a novel automated segmentation method based on an eight- neighbor region growing algorithm with left-right scanning and four-corner rotating and scanning is proposed in this pa- per. The proposed method consists of four main stages： image binarization, rough segmentation of lung, image denoising and lung contour refining. First, the binarization of images is done and the regions of interest are extracted. After that, the rough segmentation of lung is performed through a general region growing method. Then the improved eight-neighbor region growing is used to remove noise for the upper, mid- dle, and bottom region of lung. Finally, corrosion and ex- pansion operations are utilized to smooth the lung boundary. The proposed method was validated on chest positron emis- sion tomography-computed tomography （PET-CT） data of 30 cases from a hospital in Shanxi, China. Experimental results show that our method can achieve an average volume overlap ratio of 96.21 ± 0.39% with the manual segmentation results. Compared with the existing methods, the proposed algorithm segments the lung in PET-CT images more efficiently and ac- curately.

关键词： pulmonary parenchyma segmentation bot-tom region of lung image binarization iterative threshold seeded region growing four-corner rotating and scanning,denoising contour refining PET-CT

Humoral immunity, the underestimated player in hepatitis B

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Cellular & Molecular Immunology 2018年第6期15卷 645-648页

作者： Shuye Zhang juanjuan zhao Zheng Zhang Shanghai Public Health Clinical Center and Institute of Biomedical Sciences Fudan UniversityShanghai 201508China Research Center for Clinical&Translational Medicine Beijing 302 HospitalBeijing 100039China

Over decades,the immunological research of hepatitis B virus(HBV)infection has focused on HBVspecific T *** chimpanzees acutely infected with HBV,the deletion of CD4+or CD8+T cells causes chronic HBV *** humans,the HBV-specific T-cell response is temporally correlated with serum HBV clearance during an acute HBV infection,whereas HBVspecific T cells are both quantitatively and qualitatively defective in chronic HBV patients.

关键词： immunity acute infection

Vulnerability of Chinese rural-to-urban migrants to social exclusion:Spatial pattern and mechanism

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Frontiers of Architectural Research 2021年第3期10卷 572-583页

作者： juanjuan zhao Haojie Pan Merih Wahid Fangzhou Liu College of Resource Environment and Tourism Capital Normal UniversityBeijing100048China Manatee County Public Works BradentonFL34208USA Department of Electrical and Computer Engineering Technical University of MunichMunich80333Germany

In response to China’s new“people-oriented urbanization”strategy,investigating the current integration situation of rural-to-urban migrants(RUMs)in cities is ***,existing studies have not focused on their subjective willingness and adaptive ***,the mechanism of RUMs’urban integration has not been fully *** conceptual framework of vulnerability,which originated from the discipline of natural hazards,is perfectly constructive to address these *** consists of three main components,including exposure,sensitivity,and adaptive *** index has been constructed and calculated by combining the analytic hierarchy process(AHP)and Delphi *** spatial pattern of vulnerability level is also analyzed with geographic information system(GIS).Furthermore,the underlying mechanism of vulnerability and its associated factors are investigated with the principle component *** major conclusions are ***,the vulnerability level of the RUMs to social exclusion presents a heterogeneous pattern between inland and coastal cities in Shandong ***,while the exposure and sensitivity level of each city correlate spatially with the vulnerability level,RUMs’adaptive capacity further moderates ***,the level of urban development is revealed to be a key factor influencing *** study offers meaningful references to promote inclusive urbanization and sustainable urban development.

关键词： RUMs Social exclusion Vulnerability Spatial pattern Mechanism

Lung Nodule Image Retrieval Based on Convolutional Neural Networks and Hashing

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Journal of Beijing Institute of Technology 2019年第1期28卷 17-26页

作者： Yan Qiang Xiaolan Yang juanjuan zhao Qiang Cui Xiaoping Du College of Computer Science and Technology Taiyuan University of Science and Technology Shanxi Coal Central Hospital

Lung medical image retrieval based on content similarity plays an important role in computer-aided diagnosis of lung *** recent years,binary hashing has become a hot topic in this field due to its compressed storage and fast query *** hashing methods often rely on highdimensional features based hand-crafted methods,which might not be optimally compatible with lung nodule ***,different hashing bits contribute to the image retrieval differently,and therefore treating the hashing bits equally affects the retrieval ***,an image retrieval method of lung nodule images is proposed with the basis on convolutional neural networks and ***,apre-trained and fine-tuned convolutional neural network is employed to learn multilevel semantic features of the lung *** components analysis is utilized to remove redundant information and preserve informative semantic features of the lung ***,the proposed method relies on nine sign labels of lung nodules for the training set,and the semantic feature is combined to construct hashing ***,returned lung nodule images can be easily ranked with the query-adaptive search method based on weighted Hamming *** experiments and evaluations on the dataset demonstrate that the proposed method can significantly improve the expression ability of lung nodule images,which further validates the effectiveness of the proposed method.

关键词： lung nodule image retrieval convolutional neural networks informative semantic features hashing

Preparation and photoelectrochemical performance of TiO_2/Ag_2Se interface composite film

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Science China Chemistry 2009年第12期52卷 2213-2218页

作者： zhao juanjuan,JIANG BangTong,ZHANG ShengYi,NIU HeLin,JIN BaoKang & TIAN YuPeng Department of Chemistry,Anhui University,Hefei 230039,China Department of Chemistry Anhui University Hefei 230039 China

Coupling TiO2 with a narrow band gap semiconductor acting as the photosensitizer has attracted much attention in solar energy exploitation. In this work,the porous TiO2 film was first formed on the conducting glass plate (CGP) substrate by the decomposition of polyethylene glycol (PEG) mixing in titanium hydroxide sol at 450℃. Then,the TiO2/Ag2Se interface composite film was fabricated by interface reaction of AgNO3 with NaSeSO3 on the activated surface of porous TiO2 film. The results of SEM and XRD analyses indicated that the porous TiO2 layer was made up of the anatase crystal,and the Ag2Se layer was made up of congregative small particles that have low-temperature α-phase structure. Due to its efficient charge separation for the photo-induced electron-hole pairs,the TiO2/Ag2Se interface composite film as-prepared has good photovoltaic property and high photocurrent response for visible light,which have been confirmed by the photoelectrochemical measurements.

关键词： TiO2/Ag2Se interface composite film preparation measurement photoelectrochemistry

Big Data-Driven Residents’ Travel Mode Choice Choice: A Research Overview

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ZTE Communications 2019年第3期17卷 9-14页

作者： zhao juanjuan XU Chengzhong MENG Tianhui Shenzhen Institutes of Advanced Technology Chinese Academy of SciencesShenzhenGuangdong 518000China University of Macao Macao SAR 999078China

The research on residents'travel mode choice mainly studies how traffic flows are shared by different traffic modes,which is the prerequisite for the government to establish transportation planning and *** methods based on survey or small data sources are difficult to accurately describe,explain and verify residents'travel mode choice ***,thanks to upgrades of urban infrastructures,many real-time location-tracking devices become *** devices generate massive real-time data,which provides new opportunities to analyze and explain resident travel mode choice behavior more accurately and more *** paper surveys the current research status of big data-driven residents'travel mode choice from three aspects:residents'travel mode identification,acquisition of travel mode influencing factors,and travel mode choice model ***,the limitations of current research and directions of future research are discussed.

关键词： intelligent transportation travel modes choice urban computing

Isolation and characterization of mpox virus from the first mpox case in Shenzhen,China

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Virologica Sinica 2024年第2期39卷 335-337页

作者： Lin Cheng Liuqing Yang Miao Wang Yabo Peng Haiyan Wang Xiaoxiang Yang juanjuan zhao Mingxia Zhang Fuxiang Wang Zheng Zhang Institute for Hepatology National Clinical Research Center for Infectious DiseaseShenzhen Third People's HospitalShenzhen518112China Department of Infectious Diseases Shenzhen Third People's HospitalShenzhen 518112China The Second Affiliated Hospital School of MedicineSouthern University of Science and TechnologyShenzhen 518112China

Dear Editor,Unlike previous outbreaks of the mpox(previously known as monkeypox),which were localized in Africa and resulted in small numbers of infections due to limited human-to-human transmission,the current outbreak beginning in May 2022,has spread rapidly primarily through human-to-human transmission in non-endemic countries(Gong et al.,2022).As of 27 Sep 2023,115 countries and regions have reported cases of mpox to the World Health Organization(WHO),bringing the total number of confirmed cases to 90,618 including 125 *** the number of new cases has decreased in most WHO regions in the second half of 2022,the curves reveal a long outbreak tail in different subregions of the *** worrying,106 mpox cases were reported in the mainland of China in June 2023.

关键词： mainland bringing