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Performance analysis and optimization for chunked network coding based wireless cooperative downloading systems

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Frontiers of Information Technology & Electronic Engineering 2017年第10期18卷 1601-1613页

作者： Xiu-xiu WEN hui-qiang wang Jun-yu LIN Guang-sheng FENG Hong-wu LV Ji-zhong HAN College of Computer Science and Technology Harbin Engineering University Institute of Information Engineering Chinese Academy of Sciences

Dense network coding(NC) is widely used in wireless cooperative downloading systems. Wireless devices have limited computing resources. Researchers have recently found that dense NC is not suitable because of its high coding complexity, and it is necessary to use chunked NC in wireless environments. However, chunked NC can cause more communications, and the amount of communications is affected by the chunk size. Therefore, setting a suitable chunk size to improve the overall performance of chunked NC is a prerequisite for applying it in wireless cooperative downloading systems. Most of the existing studies on chunked NC focus on centralized wireless broadcasting systems, which are different from wireless cooperative downloading systems with distributed features. Accordingly, we study the performance of chunked NC based wireless cooperative downloading systems. First, an analysis model is established using a Markov process taking the distributed features into consideration, and then the block collection completion time of encoded blocks for cooperative downloading is optimized based on the analysis model. Furthermore, queuing theory is used to model the decoding process of the chunked NC. Combining queuing theory with the analysis model, the decoding completion time for cooperative downloading is optimized, and the optimal chunk size is derived. Numerical simulation shows that the block collection completion time and the decode completion time can be largely reduced after optimization.

关键词： Wireless environments Cooperative downloading Chunked network coding Markov process

PML Suppresses Influenza Virus Replication by Promoting FBXW7 Expression

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Virologica Sinica 2021年第5期36卷 1154-1164页

作者： Hai-Yan Yan hui-qiang wang Ming Zhong Shuo Wu Lu Yang Ke Li Yu-Huan Li CAMS Key Laboratory of Antiviral Drug Research Institute of Medicinal BiotechnologyChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China Beijing Key Laboratory of Antimicrobial Agents Institute of Medicinal BiotechnologyChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China NHC Key Laboratory of Biotechnology of Antibiotics Institute of Medicinal BiotechnologyChinese Academy of Medical ScienceBeijing 100050China

Influenza A viruses(IAV)are responsible for seasonal flu epidemics,which can lead to high morbidity and mortality each *** other viruses,influenza virus can hijack host cellular machinery for its *** cells have evolved diverse cellular defense to resist the invasion of *** the main components of promyelocytic leukemia protein nuclear bodies(PML-NBs),PML can inhibit the replication of many medically important viruses including ***,the mechanism of PML against IAV is *** the present study,we found PML was induced in response to IAV infection and ectopic expression of PML could inhibit IAV replication,whereas knockdown of endogenous PML expression could enhance IAV *** studies showed that PML increased the expression of FBXW7 by inhibiting its K48-linked ubiquitination and enhanced the interaction between FBXW7 and SHP2,which negatively regulated IAV replication during ***,PML stabilized RIG-I to promote the production of typeⅠ***,these data indicated that PML inhibited IAV replication by enhancing FBXW7 expression in the antiviral immunity against influenza virus and extended the mechanism of PML in antiviral immunity.

关键词： Influenza A virus(IAV) Promyelocytic leukemia(PML) FBXW7 RIG-I

Effect of Preoperative Double-J Ureteral Stenting before Flexible Ureterorenoscopy on Stone-free Rates and Complications

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Current Medical Science 2021年第1期41卷 140-144页

作者： Pei-de BAI Tao wang Hai-chao HUANG Zhun WU Xue-gang wang Jia-xuan QIN hui-qiang wang Bin CHEN Meng-bo HU Jin-chun XING The Key Laboratory of Urinary Tract Tumors and Calculi Department of Urology SurgeryThe First Affiliated Hospital of Xiamen UniversityXiamen361003China Department of Urology Huashan HospitalFudan UniversityShanghai200000China

The effect of preoperative Double-J(DJ)ureteral stenting before flexible ureterorenoscopy(FURS)in the treatment for urinary stones was *** retrospectively enrolled 306 consecutive patients who underwent FURS from Jan.2014 to *** the patients were classified into two groups according to whether they had DJ ureteral stenting before *** characteristics(age,sex,stone location,stone size,surgical success rate,operation time,stone-free rate of the first day after surgery,stone-free rate of the first month after surgery,total complication rate)were compared using Chi-square test for categorical variables and Kruskal-Wallis test for continuous *** total,306 patients were included in this *** group of DJ stenting before FURS included 203(66.3%)patients,and non-DJ stenting before FURS was observed in 103(33.7%)*** group of DJ stenting before FURS was significantly associated with a shorter operation time(53.8 vs.59.3 min,P<0.001),a higher stone-free rate of the first day after surgery(69.0%vs.51.5%,P=0.003).However,statistical significant differences were not found in the age,sex,stone location,stone size,surgical success rate,stone-free rate of the first month after surgery(89.2%vs.81.6%,P=0.065)and total complication rate(5.4%vs.9.7%,P=0.161)between the two *** DJ ureteral stenting before FURS could reduce the operation time and increase stone-free rate of the first day after ***,it might not benefit the stone-free rate of the first month after surgery and reduce the complication *** DJ stenting should be not routinely performed.

关键词： Double-J ureteral stenting flexible ureterorenoscopy stone-free rate complication rate

Temperature Difference Between the Air and Organs of Rice Plant and Its Relation to Spikelet Fertility

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Agricultural Sciences in China 2008年第6期7卷 678-685页

作者： YAN Chuan DING Yan-feng LIU Zheng-hui wang qiang-sheng LI Gang-hua HE Ying wangShao-hua Key Laboratory of Crop Growth Regulation Ministry of Agriculture/Hi-Tech Key Laboratory of Information Agriculture of Jiangsu Province Nanjing Agricultural University Nanjing 210095 P.R.China

Based on the experiment of measuring panicles and leaves, air temperature, and humidity above the canopy of rice cultivars after heading in 2005 and 2006, we investigated the temperature difference （TD） between the air and organs of rice plant and its relationship with spikelet fertility. The results showed that TDs between the air and organs of rice varied with air temperature, air humidity, and plant type. For similar air humidity, TDs were lower at the air temperature of 28.5℃ than at higher temperature of 35.5℃, whereas for the same air temperature, the TDs decreased as the air humidity increased. TDs were also affected by plant type of the cultivars. Erect panicle cultivars showed higher TDs than those with droopy panicles under similar climatic conditions, and cultivars with panicles above flag leaf （PAFL） had higher TDs than those with panicles below the flag leaf （PBFL）. Cultivars grown in a location with lower air humidity and higher temperature, such as Taoyuan, China, had higher spikelet fertility than those in higher humidity under the similar air temperature during the grain filling stage. This is partially attributed to the larger TDs under the lower humidity. Rowspacing and the ratio of basal-tillering to panicle-spikelet fertilizer showed a significant influence on TD and subsequently on spikelet fertility, suggesting the possibility of increasing spikelet fertility by agronomic management.

关键词： rice air temperature temperature of organs spikelet fertility

Cellular mechanism for spontaneous calcium oscillations in astrocytes

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Acta Pharmacologica Sinica 2006年第7期27卷 861-868页

作者： Tong-fei wang~2 Chen ZHOU~2 Ai-hui TANG Shi-qiang wang Zhen CHAI~3 State Key Laboratory of Biomembrane and Membrane Biotechnology,College of Life Sciences,Peking University,Beijing 100871,China State Key Laboratory of Biomembrane and Membrane Biotechnology College of Life Sciences Peking University Beijing China

Aim:To determine the Ca2+source and cellular mechanisms of spontaneous Ca2+oscillations in hippocampal ***:The cultured cells were loadedwith Fluo-4 AM,the indicator of intracellular Ca2+,and the dynamic Ca2+tran-sients were visualized with confocal laser-scanning ***:Thespontaneous Ca2+oscillations in astrocytes were observed first in co-culturedhippocampal neurons and *** oscillations were not affected bytetrodotoxin(TTX)treatment and kept up in purity cultured *** Ca2+oscillations were not impacted after blocking the voltage-gatedCa2+channels or ethylenediamine tetraacetic acid(EDTA)bathing,indicating thatintracellular Ca2+elevation was not the result of extracellular Ca2+***,the correlation between the spontaneous Ca2+oscillations and theCa2+store in endoplasmic reticulum(ER)were investigated with *** oscillations were:1)enhanced when cells were exposed to bothlow Na~+(70 mmol/L)and high Ca2+(5 mmol/L)solution,and eliminated completelyby 2 μmol/L thapsigargin,a blocker of sarcoplasmic reticulum Ca2+-ATPase;and2)still robust alter the application with either 50μmol/L ryanodine or 400μmol/Ltetracaine,two specific antagonists of ryanodine receptors,but depressed in adose-dependent manner by 2-APB,an InsP3receptors(InsP3R)***:InsP3R-induced ER Ca2+release is an important cellular mechanismfor the initiation of spontaneous Ca2+oscillation in hippocampal astrocytes.

关键词： hippocampal astrocytes spontaneous Ca2+ oscillations endoplasmic reticulum Ca2+ store InsP3 receptors confocal laser scanning microscope

Analyzing the service availability of mobile cloud computing systems by fluid-flow approximation

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Frontiers of Information Technology & Electronic Engineering 2015年第7期16卷 553-567页

作者： Hong-wu LV Jun-yu LIN hui-qiang wang Guang-sheng FENG Mo ZHOU College of Computer Science and Technology Harbin Engineering University Harbin 150001 China

Mobile cloud computing （MCC） has become a promising technique to deal with computation- or data-intensive tasks. It overcomes the limited processing power, poor storage capacity, and short battery life of mobile devices. Providing continuous and on-demand services, MCC argues that the service must be available for users at anytime and anywhere. However, at present, the service availability of MCC is usually measured by some certain metrics of a real-world system, and the results do not have broad representation since different systems have different load levels, different deployments, and many other random factors. Meanwhile, for large-scale and complex types of services in MCC systems, simulation-based methods （such as Monte- Carlo simulation） may be costly and the traditional state-based methods always suffer from the problem of state-space explosion. In this paper, to overcome these shortcomings, fluid-flow approximation, a breakthrough to avoid state-space explosion, is adopted to analyze the service availability of MCC. Four critical metrics, including response time of service, minimum sensing time of devices, minimum number of nodes chosen, and action throughput, are def＇med to estimate the availability by solving a group of ordinary differential equations even before the MCC system is fully deployed. Experimental results show that our method costs less time in analyzing the service availability of MCC than the Markov- or simulation-based methods.

关键词： Service availability Mobile cloud computing Fluid-flow approximation Ordinary differential equations

Current Global Almond Trade and Its Consumption Patterns Analysis

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Forestry Studies in China 2005年第4期7卷 35-40页

作者： wang hui-qiang wang Jian-zhong Wu Di wang Feng-jun College of Biological Sciences and Biotechnology Beijing Forestry University Beijing 100083 P. R. China

This article aims to investigate the current situation of the international almond trade and its consumption patterns. Traditionally, almonds are characterized by their good taste and high quality and regarded as an ideal source of several natural health nutrients. At present, the United States is the leading almond producer and exporter in the world, accompanied by Germany, Spain and Japan, the biggest almond importing countries. In order to study almond consumption patterns, two indicators were used in our study, the Food Consumer Location Ratio （FCLR） and the Food Consumer Location Relative Ratio （FCLRR）. Furthermore, to identify the almond consumption groups, we carried out two cluster analyses based on FCLR and FCLRR values, Finally, an analysis of the factors which have an impact on a country＇s almond consumption was conducted. It shows that income level, endowment of resources and tradition as well as dietary habits are key factors that help to shape a country＇s almond consumption pattern.

关键词： almonds global trade consumption patterns cluster analysis

DGTM： a dynamic grouping based trust model for mobile peer-to-peer networks

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Frontiers of Information Technology & Electronic Engineering 2017年第4期18卷 559-569页

作者： Mei-juan JIA hui-qiang wang Jun-yu LIN Guang-sheng FENG Hai-tao YU College of Computer Science and Technology Harbin Engineering University Harbin 150001 China College of Computer Science and Information Technology Daqing Normal University Daqing 163712 China Institute of Information Engineering Chinese Academy of Sciences Beijing 100093 China College of Tourism Guilin University of Technology Guilin 541001 China

The special characteristics of the mobile environment, such as limited bandwidth, dynamic topology, heterogeneity of peers, and limited power, pose additional challenges on mobile peer-to-peer （MP2P） networks. Trust management becomes an essential component of MP2P networks to promote peer transactions. However, in an MP2P network, peers frequently join and leave the network, which dynamically changes the network topology. Thus, it is difficult to establish long-term and effective trust relationships among peers. In this paper, we propose a dynamic grouping based trust model （DGTM） to classify peers. A group is formed according to the peers＇ interests. Within a group, mobile peers share resources and tend to keep stable trust relationships. We propose three peer roles （super peers, relay peers, and ordinary peers） and two novel trust metrics （intragroup trust and intergroup trust）. The two metrics are used to accurately measure the trust between two peers from the same group or from different groups. Simulations illustrate that our proposed DGTM always achieves the highest successful transaction rate and the best communication overhead under different circumstances.

关键词： Mobile P2P networks Trust

RF Optimizer Model for Predicting Compressive Strength of Recycled Concrete

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 215-223页

作者： LIU Lin wang Liuyan wang hui SUN Huayue School of Civil Engineering and Architecture Shenyang UniversityShenyang 110000China

Traditional machine learning(ML)encounters the challenge of parameter adjustment when predicting the compressive strength of reclaimed *** address this issue,we introduce two optimized hybrid models:the Bayesian optimization model(B-RF)and the optimal model(Stacking model).These models are applied to a data set comprising 438 observations with five input variables,with the aim of predicting the compressive strength of reclaimed ***,we evaluate the performance of the optimized models in comparison to traditional machine learning models,such as support vector regression(SVR),decision tree(DT),and random forest(RF).The results reveal that the Stacking model exhibits superior predictive performance,with evaluation indices including R2=0.825,MAE=2.818 and MSE=14.265,surpassing the traditional ***,we also performed a characteristic importance analysis on the input variables,and we concluded that cement had the greatest influence on the compressive strength of reclaimed concrete,followed by ***,the Stacking model can be recommended as a compressive strength prediction tool to partially replace laboratory compressive strength testing,resulting in time and cost savings.

关键词： machine learning recycled concrete compressive strength