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Journal of Integrative Agriculture 2013年第6期12卷 1112-1121页

作者： zhou jie-hong YAN Zhen LIU Qing-yu Center for Agricultural and Rural Development Zhejiang University

In recent years, the Chinese government has highlighted the importance of adopting hog safety/quality traceability, and a growing amount of research continues to entice firms to adopt traceability systems. In this study, a survey was conducted on a sample of pig slaughtering and processing firms in Zhejiang, China through personal interviews and emails. The aim of this study was to examine the determinants of firm behavior on the implementation of voluntary traceability systems with more stringent standards and controls than those of the mandatory system in China. The results revealed that motivation based on product quality improvement, capital ability and role perception （business type） had significantly positive relationships with a firm＇s voluntary traceability. Other incentives, such as operation improvement, recall risk reduction, reduced occurrence of safety issues, and technical strength were not found to be supportive in our study. This study provides an opportunity to better understand the determinants of firm behavior on voluntary traceability, particularly in light of the fact that some Chinese firms are facing the threat of criminal action for the use of illegal additives and the abuse of Clenbuterol. Policy recommendations on encouraging the implementation of pork safety voluntary traceability by hog slaughtering and processing firms are also discussed.

关键词： voluntary traceable behavior product quality improvement capital ability role perception hog slaughtering and processing firm

A Class of Weighted Estimators for Additive Hazards Model in Case-cohort Studies

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Acta Mathematicae Applicatae Sinica 2014年第4期30卷 1153-1168页

作者： Cai-lin DONG jie zhou Liu-quan SUN School of Mathematics and Statistics Huazhong Normal University Academy of Mathematics and Systems Science Chinese Academy of Sciences School of Mathematics Capital Normal University

Case-cohort sampling is a commonly used and efficient method for studying large cohorts. In many situations, some covariates are easily measured on all cohort subjects, and surrogate measurements of the expensive covariates also may be observed. In this paper, to make full use of the covariate data collected outside the case-cohort sample, we propose＇a class of weighted estimators with general time-varying weights for the additive hazards model, and the estimators are shown to be consistent and asymptotically normal. We also identify the estimator within this class that maximizes efficiency, and simulation studies show that the efficiency gains of the proposed estimator over the existing ones can be substantial in practical situations. A real example is provided.

关键词： additive hazards case-cohort study stratified sampling survival data two-phase design

Holocene Dune Mobility and Forcing Mechanisms at the Northern Margin of the East Asian Monsoon

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Acta Geologica Sinica(English Edition) 2013年第4期87卷 1168-1178页

作者： HE Zhong zhou jie YANG Linhai HE Hongming Institute of Soil and Water Conservation Northwest A&F University Institute of Soil and Water Conservation Chinese Academy of Sciences & Ministry of Water Resource Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences

Dune fields at the northern margin of the East Asian monsoon （EAM）, are mosaics of mobile and vegetation-stabilized aeolian dunes. These sand dunes are highly sensitive to environmental change, thus the distribution and the timing of their development may provide important clues to past environmental dynamics. Due to the strong wind erosion and dune migration, long and continuous stratigraphic records are seldom preserved. Synthesizing a large body of events, ultimately producing a relatively complete and high-resolution record, may be a proper method to investigate the dune development history and climate change. In this study, we synthesized a large body of luminescence ages for aeolian deposits from the Mu Us, Otindag, Horqin dune fields at the northern margin of the EAM. The results show that these dune fields, as a whole experienced a most extensive mobility during the early Holocene, followed by a widespread shift toward limited mobility and soil development in the mid-Holocene, and widespread reactivation occurred during late Holocene. The dune developments are directly linked to the effective moisture change controlled by the EAM changes, which respond to the low latitude summer insolation variation. The increased subsidence at the margin contrary to the core EAM, the delay from the feedback of the soil-vegetation-air coupled system, the increased evaporation due to the high temperature all play partial role in the lag of the margin EAM effective moisture change to the low latitude summer insolation. The asynchronous end of the wetter mid-Holocene mainly responds to the southeastwardly shift of the precipitation belt, while the regional sensitivity, response speed and internal feedback also contributed. The correspondence between dune records and North Atlantic drift-ice records of the rapid climate changes implies a close relationship between North Atlantic climate and the frequent dune activity at the northern margin of EAM.

关键词： Holocene dune mobility luminescence dating East Asian Monsoon forcing mechanisms

One-pot synthesis of dual-state emission(DSE)luminogens containing the V-shape furo[2,3-b]furan scaffold

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Chinese Chemical Letters 2021年第1期32卷 445-448页

作者： jie zhou Manna Huang Xinhai Zhu Yiqian Wan School of Chemical Engineering and Technology Guangdong Engineering Technology Research Center for Platform Chemicals from Marine Biomass and Their FunctionalizationSun Yat-sen UniversityZhuhai 519082China Instrument Analysis&Research Center Sun Yat-sen UniversityGuangzhou 510275China

To discover novel fluoro p hores of solution and solid dual-state emission(DSE) materials,unique V-shape furo[2,3-b]furans have been designed and synthesized by a one-pot method for the first time and their photoluminescent properties have been explored in benzene,THF,DMF and DMSO,as well as in the solid *** the best example,2,5-bis(4-(9 H-carbazol-9-yl)phenyl)-6 a-amino-3 a,6 a-dihydrofuro[2,3-b]furan-3,3 a,4-trica rbonitrile(3 g) exhibited solution and solid DSE properties in THF,benzene,and in the solid state with quantum yields of 55%,92%,and 45%,respectively.

关键词： One-pot synthesis Furo[2,3-b]furan Selenium dioxide V-Shape Dual-state emission

Fault Information Recognition for On-board Equipment of High-speed Railway Based on Multi-neural Network Collaboration

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International Journal of Automation and computing 2021年第6期18卷 935-946页

作者： Lu-jie zhou Jian-Wu Dang Zhen-Hai Zhang School of Automation and Electrical Engineering Lanzhou Jiaotong UniversityLanzhou 730070China Gansu Provincial Engineering Research Center for Artificial Intelligence and Graphic&Image Processing Lanzhou 730070China

It is of great significance to guarantee the efficient statistics of high-speed railway on-board equipment fault information,which also improves the efficiency of fault analysis. Considering this background, this paper presents an empirical exploration of named entity recognition(NER) of on-board equipment fault information. Based on the historical fault records of on-board equipment, a fault information recognition model based on multi-neural network collaboration is proposed. First, considering Chinese recorded data characteristics, a method of constructing semantic features and additional features based on character granularity is proposed. Then, the two feature representations are concatenated and passed into the gated convolutional layer to extract the dependencies from multiple different subspaces and adjacent characters in parallel. Next, the local features are transmitted to the bidirectional long short-term memory(BiLSTM) to learn long-term dependency information. On top of BiLSTM, the sequential conditional random field(CRF) is used to jointly decode the optimized tag sequence of the whole sentence. The model is tested and compared with other representative baseline models. The results show that the proposed model not only considers the language characteristics of on-board fault records, but also has obvious advantages on the performance of fault information recognition.

关键词： Train control system Chinese named entity recognition(NER) character feature gating mechanism bidirectional long short-term memory(BiLSTM)

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Geometrical statistical channel model arisen from scatterers around the mobile with an inverted-parabolic spatial distribution

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The Journal of China Universities of Posts and Telecommunications 2012年第5期19卷 1-8页

作者： zhou jie LI Chun-mei QIU Lin HISAKAZU Kikuchi Department of Communications Nanjing University of Information Science and Technology Nanjing 210044 China Department of Electronic and Electrical Engineering Niigata University Niigata 950-2181 Japan

In this paper, firstly presented a geometrically based statistical channel model with scatterers that are with an inverted parabolic spatial distribution around mobile station （MS） within a circle wherein the base station （BS） and MS are included. This paper proposed a technique to simply derive probability density functions （PDFs） of angle of arrival （AOA）, time of arrival （TOA） and Doppler spectra to characterize the outdoor macrocell and microcell environments by employing various distances between BS and MS, or different size of circular region. Employing this channel model, we analyze the impacts of a directional antenna at BS with the main-lobe width 2~z on the fading and the Doppler spectra.

关键词： inverted parabolic PDFs circular and elliptical scattering models directional antenna macrocell and microcell

Effect of alloying on high temperature fatigue performance of ZL114A(Al-7Si) alloy

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中国有色金属学会会刊：英文版 2012年第S3期22卷 661-667页

作者： DONG Xu-gang zhou jie JIA Yao-jun LIU Bin College of Materials Science and Engineering Chongqing University Baoji Petpoleum Steel Pipe Co. Ltd.

The effect of Cu,Fe and Ni on high-temperature mechanical performance and fatigue properties of ZL114A alloy was studied through high temperature fatigue test and *** results show that the three elements have a detrimental influence on high temperature cyclic fatigue *** the contents (mass fraction) of Fe,Cu and Ni in ZL114A alloy are 0.28%,1.53% and 0.16%,respectively,the high temperature tensile strength and cyclic fatigue of ZL114A alloy are improved from 194 MPa and 40.2 MPa to 236 MPa and 48.2 MPa by *** main reason that high temperature tensile strength and cyclic fatigue of ZL114A alloy are improved significantly is that the three elements greatly improve the proportion of Cu/Mg in ZL114A alloy and nickel content.

关键词： aluminum alloys alloying high temperature fatigue fracture

A Hybrid Conjugate Gradient Algorithm for Nonconvex Functions and Its Applications in Image Restoration Problems

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Journal of the Operations Research Society of China 2023年第4期11卷 759-781页

作者： Gong-Lin Yuan Ying-jie zhou Meng-Xiang Zhang College of Mathematics and Information Science Center for Applied Mathematics of GuangxiGuangxi UniversityNanning530004China

It is prominent that conjugate gradient method is a high-efficient solution way for large-scale optimization ***,most of the conjugate gradient methods do not have sufficient descent *** this paper,without any line search,the presented method can generate sufficient descent directions and trust region *** use some suitable conditions,the global convergence of the method is established with Armijo line ***,we study the proposed method for solving nonsmooth problems and establish its global *** experiments show that the presented method can be applied to solve smooth and nonsmooth unconstrained problems,image restoration problems and Muskingum model successfully.

关键词： Conjugate gradient Smooth and nonsmooth problems Nonconvex functions Global convergence

Enzyme-instructed self-assembly of peptides containing phosphoserine to form supramolecular hydrogels as potential soft biomaterials

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Frontiers of Chemical Science and Engineering 2017年第4期11卷 509-515页

作者： jie zhou Xuewen Du Jiaqing Wang Natsuko Yamagata Bing Xu Department of Chemistry Brandeis University 415 South St. Waltham MA 02453 USA.

Enzyme-instructed self-assembly （EISA） offers a facile approach to explore the supramolecular assemblies of small molecules in cellular milieu for a variety of biomedical applications. One of the commonly used enzymes is phosphatase, but the study of the substrates of phosphatases mainly focuses on the phos- photyrosine containing peptides. In this work, we examine the EISA of phosphoserine containing small peptides for the first time by designing and synthesizing a series of precursors containing only phosphoserine or both phos- phoserine and phosphotyrosine. Conjugating a phospho- serine to the C-terminal of a well-established self- assembling peptide backbone, （naphthalene-2-1y）-acetyl- diphenylalanine （NapFF）, affords a novel hydrogelation precursor for EISA. The incorporation ofphosphotyrosine, another substrate of phosphatase, into the resulting precursor, provides one more enzymatic trigger on a single molecule, and meanwhile increases the precursors＇ propensity to aggregate after being fully dephosphorylated. Exchanging the positions of phosphorylated serine and tyrosine in the peptide backbone provides insights on how the specific molecular structures influence self-assembling behaviors of small peptides and the subsequent cellular responses. Moreover, the utilization of D-amino acids largely enhances the biostability of the peptides, thus providing a unique soft material for potential biomedical applications.

关键词： enzyme-instructed self-assembly phosphoser-ine phosphatase supramolecular hydrogel

Fault Classification for On-board Equipment of High-speed Railway Based on Attention Capsule Network

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International Journal of Automation and computing 2021年第5期18卷 814-825页

The conventional troubleshooting methods for high-speed railway on-board equipment, with over-reliance on personnel experience, is characterized by one-sidedness and low efficiency. In the process of high-speed train operation, numerous text-based onboard logs are recorded by on-board computers. Machine learning methods can help technicians make a correct judgment of fault types using the on-board log reasonably. Therefore, a fault classification model of on-board equipment based on attention capsule networks is proposed. This paper presents an empirical exploration of the application of a capsule network with dynamic routing in fault classification. A capsule network can encode the internal spatial part-whole relationship between various entities to identify the fault types. As the importance of each word in the on-board log and the dependencies between them have a significant impact on fault classification, an attention mechanism is incorporated into the capsule network to distill important information. Considering the imbalanced distribution of normal data and fault data in the on-board log, the focal loss function is introduced into the model to adjust the imbalanced data. The experiments are conducted on the on-board log of a railway bureau and compared with other baseline models. The experimental results demonstrate that our model outperforms the compared baseline methods, proving the superiority and competitiveness of our model.

关键词： On-board equipment fault classification capsule network attention mechanism focal loss

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