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Journal of Central South University 2012年第10期19卷 2940-2948页

作者：余先锋全涌顾明 State Key Laboratory of Disaster Reduction in Civil Engineering(Tongji University)

The equations governing wind-induced internal pressure responses for a two-compartment building with a dominant opening and background porosity were *** unsteady form of the Bernoulli equation,the law of mass conservation,and adiabatic equation were used for the *** precision of the governing equations was verified by a wind tunnel test on a rigid model of a low-rise *** results show that the governing equations can effectively analyze the wind-induced internal pressure *** internal pressure responses in both compartments are suppressed due to the additional damping provided by background *** responses of internal pressure in both compartments,especially in the compartment without an external opening,decrease with increased lumped leakage area.

关键词： dominant opening internal pressure background porosity additional damping wind tuunel test

Syntheses of Substituted Indan-1-onesand Indenes

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Chemical Research in Chinese Universities 1999年第3期15卷 281-285页

作者： YASIN Tariq FAN Zhi-qiang feng Lin-xian Department of Polymer Science and Engineering Zhejiang UniversityHangzhou 310027P.R.China

The syntheses of three novel substituted indanones namely 2,7 dimethylindan 1 one, 2 methyl 4,7 diethylindan 1 one and 2,4 dimethyl 7 methoxyindan 1 one are described. These indanones were prepared by different routes involving intramolecular ring closure of aryl substituted compounds by Friedel Crafts reaction. The t butyl was used as the positional protective group in the selective preparation of 2,7 dimethylindan 1 one. The corresponding indenes were prepared by reduction and dehydration reactions from these indanones.

关键词： Friedel Crafts reaction 1 Indanone Substituted indene

Research Article Understanding the role of streamers in livestreaming commerce:a vocal–visual perspective

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Journal of Management Analytics 2023年第2期10卷 247-269页

作者： Wei Gao Ning Jiang feng gu College of Economics and Management Southwest UniversityChongqingPeople’s Republic of China Antai College of Economics and Management Shanghai Jiao Tong UniversityShanghaiPeople’s Republic of China

Despite streamers having earned widespread attention,no studies have explored the relationship between streamers and customer engagement from a vocal–visual perspective in the livestreaming commerce *** on the elaboration likelihood model,we examine how streamers’speech rate and facial attractiveness influence customer engagement using 434 pieces of unstructured livestreaming video data extracted from *** findings show that speech rate is positively related to customer engagement *** attractiveness has a significant positive effect on the number of comments and viewers obtained,but it has no impact on the number of likes received in a *** rate and facial attractiveness demonstrate a significant interaction effect,increasing customer engagement ***,the numbers of comments and viewers obtained are positively related to sales *** results offer new insights into the vital role of streamers and provide practical implications for improving customer engagement in livestreaming commerce.

关键词： speech rate facial attractiveness customer engagement unstructured data livestreaming commerce

A construction of inter-group complementary codes with flexible ZCZ length

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第10期12卷 846-854页

作者： Li-fang feng xian-wei ZHOU Ping-zhi FAN School of Information Engineering University of Science and Technology Beijing Beijing 100083 China Provincial Key Lab of Information Coding and Transmission Institute of Mobile Communications Southwest Jiaotong University Chengdu 610031 China

A general construction of inter-group complementary (IGC) codes is proposed based on perfect complementary (PC) codes,interleaving operation,and the orthogonal *** correlation properties of the newly constructed IGC codes can be described as follows:(1) the autocorrelation sidelobes of the codes are zeros in the zero correlation zone (ZCZ);(2) the cross-correlation functions (CCFs) between any two different codes of the same group are zeros in the ZCZ;(3) the CCFs between any two codes of different groups are zeros *** key point of this construction is that the ZCZ length of the generated IGC codes can be chosen *** is well known that there is a limitation between the ZCZ length and the number of mates;that is,the smaller is the length of ZCZ,the more are the IGC codes that can be ***,if we can choose the ZCZ length of the IGC codes flexibly according to the requirement of the system,more users can be accommodated in the system.

关键词： Z-complementary codes Perfect complementary codes Zero correlation zone

Zebra chip disease incidence on potato is influenced by timing of potato psyllid infestation, but not by the host plants on which they were reared

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Insect Science 2009年第5期16卷 399-408页

作者： feng Gao John Jifon xiangbing Yang Tong-xian Liu Texas AgriLife Research Texas A&M University System 2415 E. Highway 83 Weslaco TX 78596 USA

The Zebra chip （ZC） syndrome is an emerging disease of potato and a major threat to the potato industry. The potato psyllid, Bactericerca cockerelli （Sulc） is believed to be a vector of the ZC pathogen, which is now thought to be Candidatus Liberibacter, a bacterium. To further understand the relationship between potato psyllid infestation and ZC disease expression, healthy potato plants at different growth stages （4, 6 and 10 weeks after germination） were exposed separately to potato psyllids that were separately reared on four solanaceous hosts plants （potato, tomato, eggplant or bell pepper） for more than 1 year. ZC symptoms, leaf rates and total nonstructural carbohydrate accumulation in leaves and tubers of healthy and psyllid-infested plants were monitored and recorded. Typical ZC symptoms were observed in leaves and tubers of all plants exposed to potato psyllids regardless of the host plant on which they were reared. This was also accompanied by significant reductions in net photosynthetic rate. Caged potato plants without exposure to potato psyllids （uninfested controls） did not show any ZC symptom in both foliage and in harvested tubers. Foliage damage and ZC expression were most severe in the potato plants that were exposed to potato psyllids 4 weeks after germination compared to plants infested at later growth stages. Tubers from potato psyllid-infested plants had significantly higher levels of reducing sugars （glucose） and lower levels of starch than those in healthy plants, indicating that potato psyllid infestation interfered with carbohydrate metabolism in either leaves or tubers, resulting in ZC expression.

关键词： Bactericerca cockerelli glucose reducing sugars starch sucrose zebra chip disease

Optimization of Processing Parameters of Power Spinning for Bushing Based on Neural Network and Genetic Algorithms

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Journal of Beijing Institute of Technology 2019年第3期28卷 606-616页

作者： Junsheng Zhao Yuantong gu Zhigang feng School of Mechanical Engineering North University of ChinaTaiyuan 030051China School of Chemistry Physics and Mechanical EngineeringQueensland University of TechnologyBrisbaneQLD 4001Australia

A neural network model of key process parameters and forming quality is developed based on training samples which are obtained from the orthogonal experiment and the finite element numerical simulation. Optimization of the process parameters is conducted using the genetic algorithm (GA). The experimental results have shown that a surface model of the neural network can describe the nonlinear implicit relationship between the parameters of the power spinning process:the wall margin and amount of expansion. It has been found that the process of determining spinning technological parameters can be accelerated using the optimization method developed based on the BP neural network and the genetic algorithm used for the process parameters of power spinning formation. It is undoubtedly beneficial towards engineering applications.

关键词： power spinning process parameters optimization BP neural network genetic algorithms (GA) response surface methodology (RSM)

The utility of two-dimensional shear wave elastography and texture analysis for monitoring liver fibrosis in rat model

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Hepatobiliary & Pancreatic Diseases International 2021年第1期20卷 46-52页

作者： Li-Hong gu guang-xiang gu Ping Wan feng-Hua Li Qiang Xia Department of Liver Surgery Renji HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai 200127China Department of Ultrasound Renji HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai 200127China

Background:Liver fibrosis is a common pathological change caused by a variety of *** diagnosis and timely treatment can reverse or delay disease progression and improve the *** study aimed to assess the potential utility of two-dimensional shear wave elastography and texture analysis in dynamic monitoring of the progression of liver fibrosis in rat ***:Twenty rats were divided into control group(n=4)and experimental groups(n=4 per group)with carbon tetrachloride administration for 2,3,4,and 6 *** liver stiffness measurement was performed by two-dimensional shear wave elastography,while the optimal texture analysis subsets to distinguish fibrosis stage were generated by *** results of elastography and texture analysis were validated through comparing with ***:Liver stiffness measurement was 6.09±0.31 kPa in the control group and 7.10±0.41 kPa,7.80±0.93 kPa,8.64±0.93 kPa,9.91±1.13 kPa in the carbon tetrachloride induced groups for 2,3,4,6 weeks,respectively(P<0.05).By texture analysis,histogram and co-occurrence matrix had the most frequency texture parameters in staging liver *** operating characteristic curve of liver elasticity showed that the sensitivity and specificity were 95.0%and 92.5%to discriminate liver fibrosis and non-fibrosis,*** texture analysis,five optimal parameters were selected to classify liver fibrosis and ***:Two-dimensional shear wave elastography showed potential applications for noninvasive monitoring of the progression of hepatic fibrosis,even in mild *** analysis can further extract and quantify the texture features in ultrasonic image,which was a supplementary to further visual information and acquired high diagnostic accuracy for severe fibrosis.

关键词： Shear wave elastography Ultrasound Texture analysis Fibrosis Rat

Effects of sodium on nitrate uptake and osmotic adjustment of Suaeda physophora

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Journal of Arid Land 2010年第3期2卷 190-196页

作者： Yuan, Junfeng Tian, ChangYan feng, gu Chinese Acad Sci Xinjiang Inst Ecol & Geog Key Lab Oasis Ecol & Desert Environm Urumqi 830011 Peoples R China China Agr Univ Coll Resource & Environm Sci Beijing 100094 Peoples R China

Na+ ions play an important role in the growth of halophyte. The effect of Na+ ions on nitrate uptake and osmotic adjustment in the euhalophyte Suaeda physophora was investigated under glasshouse conditions. Seedlings were exposed to 1 mmol/L NaCl (control),300 mmol/L NaCl,150 mmol/L NaCl plus 150 mmol/L KCl or 300 mmol/L KCl treatments for 24 d. Dry weight was not affected greatly by different salt treatments,but water content and succulence in leaves of S. physophora were significantly increased at 300 mmol/L NaCl and 150 mmol/L NaCl plus 150 mmol/L KCl treatments. The concentrations of Na+ and NO3’ in leaves of S. physophora were the highest at 150 mmol/L NaCl plus 150 mmol/L KCl,but lowest at 300 mmol/L KCl treatment. Moreover,the increase of NO3’ concentration did not result in the decrease of Cl-concentration at 150 mmol/L NaCl plus 150 mmol/L KCl treatments. The estimated contribution of NO3’ to osmotic potential (CNO3) in leaves of S. physophora was 9.8% at 150 mmol/L NaCl plus 150 mmol/L KCl,and CNa and CCl were 31.0% and 23.3%,respectively. However,CNO3,CNa and CCl were respectively 1.6%,7.9% and 11.9% at 300 mmol/L KCl treatment. It is concluded that Na+ stimulates NO3’ absorption and the stimulation is independent on the internal or the external Cl-concentration in the euhalophyte S. physo-phora. These characteristics may explain the high levels of N in leaves of saline desert plants in arid ecosystem.

关键词： euhalophyte Suaeda physophora NaCl KCl NO3’

Distribution Approximation of Shrinkage Estimate in Censored Regression Model via Randomly Weighting Method

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Acta Mathematicae Applicatae Sinica 2019年第2期35卷 421-434页

作者： xian-hui LIU Zhan-feng WANG Yao-hua WU Department of Statistics and Finance University of Science and Technology of China School of Statistics and Research Center of Applied Statistics Jiangxi University of Finance and Economics

Censored regression("Tobit") model is a special case of limited dependent variable regression model, and plays an important role in econometrics. Based on this model, all kinds of methods for variable or group variable selection have been developed and the corresponding shrinkage parameter estimates are widely studied. However, asymptotic distributions of the shrinkage estimates involve unknown nuisance parameters,such as density function of error term. To avoid estimating nuisance parameters, this paper presents a randomly weighting method to approximate to the asymptotic distribution of the shrinkage estimate. A computation procedure of random approximation is provided and asymptotic properties of the randomly weighting estimates are also obtained. The proposed methods are evaluated with extensively numerical studies and a women labor supply example.

关键词： Censored regression model variable selection asymptotic properties randomly weighting

Quantifying the quantumness of ensembles via unitary similarity invariant norms

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Frontiers of physics 2018年第4期13卷 291-295页

作者： xian-Fei Qi Ting Gao feng-Li Yan College of Mathematics and Information Science Hebei Normal University Shijiazhuang 050024 China College of Physics Science and Information Engineering Hebei Normal University Shijiazhuang 050024 China

The quantification of the quantumness of a quantum ensemble has theoretical and practical signif- icance in quantum information theory. We propose herein a class of measures of the quantumness of quantum ensembles using the unitary similarity invariant norms of the commutators of the con- stituent density operators of an ensemble. Rigorous proof shows that they share desirable properties for a measure of quantumness, such as positivity, unitary invariance, concavity under probabilistic union, convexity under state decomposition, decreasing under coarse graining, and increasing under fine graining. Several specific examples illustrate the applications of these measures of quantumness in studying quantum information.

关键词： the quantumness of quantum ensemble measures of quantumness of quantum ensembles unitary similarity invariant norms