检索结果-南通市图书馆

Space-time prism in multimodal supernetwork-Part 1:Methodology

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in Transportation Research 2021年第1期1卷 130-138页

作者： jing Qin Feixiong liao Urban Planning and Transportation Group Eindhoven University of TechnologyEindhoven5600 MBthe Netherlands

Space-time prism(STP)modeling offers a theoretical base for various person-based space-time accessibility *** has been challenging to construct STPs in multimodal transportation networks because of the vast multimodal trip chaining options between private vehicles and public *** study suggests an effective method for narrowing down the trip chaining *** method involves three incremental strategies to eliminate parking locations that contribute little to enlarging the ***,an upper bound potential path area(PPA)is constructed to remove all inferior parking ***,the study area is partitioned and only complementary parking locations attractive to trip chaining are ***,triangular inequalities are applied for *** selected parking locations are used to construct a compact multimodal supernetwork encompassing one episode of activity ***,the STP and PPA can be found by an existing twostage bidirectional search *** tests are conducted to demonstrate the effectiveness of the *** is found that 1-2 orders of speedups can be achieved with little compromising the accuracy of measuring space-time *** suggested method is applicable for measuring space-time accessibility in large-scale multimodal transportation networks.

关键词： Space-time prism Accessibility Trip chaining Multimodal supernetwork

Packet Cache-Forward Method Based on Improved Bayesian Outlier Detection for Mobile Handover in Satellite Networks

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

China Communications 2016年第6期13卷 167-177页

作者： Hefei Hu Dongming yuan Mingxia liao yuan'an Liu School of Information and Communication Engineering Beijing University of Posts and Telecommunications School of Electronic Engineering Beijing University of Posts and Telecommunications

In this paper, we propose a Packet Cache-Forward(PCF) method based on improved Bayesian outlier detection to eliminate out-of-order packets caused by transmission path drastically degradation during handover events in the moving satellite networks, for improving the performance of TCP. The proposed method uses an access node satellite to cache all received packets in a short time when handover occurs and forward them out in order. To calculate the cache time accurately, this paper establishes the Bayesian based mixture model for detecting delay outliers of the entire handover scheme. In view of the outliers' misjudgment, an updated classification threshold and the sliding window has been suggested to correct category collections and model parameters for the purpose of quickly identifying exact compensation delay in the varied network load statuses. Simulation shows that, comparing to average processing delay detection method, the average accuracy rate was scaled up by about 4.0%, and there is about 5.5% cut in error rate in the meantime. It also behaves well even though testing with big dataset. Benefiting from the advantage of the proposed scheme in terms of performance, comparing to conventional independent handover and network controlled synchronizedhandover in simulated LEO satellite networks, the proposed independent handover with PCF eliminates packet out-of-order issue to get better improvement on congestion window. Eventually the average delay decreases more than 70% and TCP performance has improved more than 300%.

关键词： satellite networks handover bayesian method outlier detection

Vibration and sound transmission loss characteristics of porous foam functionally graded sandwich panels in thermal environment

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2023年第6期44卷 897-916页

作者： Wenhao yuan Haitao liao Ruxin GAO Fenglian LI Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China School of Mechanical and Electrical Engineering Beijing Information Science and Technology UniversityBeijing 100192China

This study investigates the vibration and acoustic properties of porous foam functionally graded(FG)plates under the influence of the temperature *** dynamics equations of the system are established based on Hamilton's principle by using the higher-order shear deformation theory under the linear displacement-strain *** displacement shape function is assumed according to the four-sided simply-supported(SSSS)boundary condition,and the characteristic equations of the system are derived by combining the motion control *** theoretical model of vibro-acoustic coupling is established by using the acoustic theory and fluid-structure coupling solution method under the simple harmonic acoustic *** system's natural frequency and sound transmission loss(STL)are obtained through programming calculations and compared with the literature and COMSOL simulation to verify the validity and reliability of the theoretical *** effects of various factors,such as temperature,porosity coefficients,gradient index,core thickness,width-to-thickness ratio on the vibration,and STL characteristics of the system,are *** results provide a theoretical basis for the application of porous foam FG plates in engineering to optimize vibration and sound transmission properties.

关键词： porous foam functionally graded(FG)plate thermal environment natural frequency sound transmission loss(STL)

On some problems of weak consistency of quasi-maximum likelihood estimates in generalized linear models

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2008年第7期51卷 1287-1296页

作者： Zhang SanGuo liao yuan School of Mathematical Sciences Graduate University of Chinese Academy of SciencesBeijing 100049China

In this paper, we explore some weakly consistent properties of quasi-maximum likelihood estimates (QMLE) concerning the quasi-likelihood equation $ \sum\nolimits_{i = 1}^n {X_i (y_i - \mu (X_i^\prime \beta ))} $ for univariate generalized linear model E(y|X) = μ(X′β). Given uncorrelated residuals {e i = Y i ? μ(X i ′ β0), 1 ? i ? n} and other conditions, we prove that $$ \hat \beta _n - \beta _0 = O_p (\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle-}$}}{\lambda } _n^{ - 1/2} ) $$ holds, where $ \hat \beta _n $ is a root of the above equation, β 0 is the true value of parameter β and $$ \underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle-}$}}{\lambda } _n $$ denotes the smallest eigenvalue of the matrix S n = ∑ i=1 n X i X i ′ . We also show that the convergence rate above is sharp, provided independent non-asymptotically degenerate residual sequence and other conditions. Moreover, paralleling to the elegant result of Drygas (1976) for classical linear regression models, we point out that the necessary condition guaranteeing the weak consistency of QMLE is S n ?1 → 0, as the sample size n → ∞.

关键词： generalized linear models (GLMs) quasi-maximum likelihood estimates (QMLE) weak consistency convergence rate 62E20 62J12

中国共病加权指数与老年人卫生服务利用的关联性研究

在线全文

学校读者我要写书评

暂无评论

中国全科医学 2025年第1期28卷 65-70页

作者：李丽萍廖婧高鑫源王力赖颖斯中山大学公共卫生学院广东省广州市510000 广东省肇庆市疾病预防控制中心传染病预防控制科 526000

背景慢性病共病给老年人卫生服务带来挑战,探索老年人慢性病共病负担对卫生服务利用的影响具有重要意义。中国共病加权指数(CMWI)是衡量我国中老年人群共病负担的指标,目前尚缺乏CMWI与卫生服务利用关联性的队列研究。目的探索老年人慢... 详细信息

背景慢性病共病给老年人卫生服务带来挑战,探索老年人慢性病共病负担对卫生服务利用的影响具有重要意义。中国共病加权指数(CMWI)是衡量我国中老年人群共病负担的指标,目前尚缺乏CMWI与卫生服务利用关联性的队列研究。目的探索老年人慢性病共病负担与卫生服务利用的关联,为改善老年人慢性病共病干预与管理提供科学依据。方法于2021年12月—2024年1月,以广东省肇庆市四会市为例,收集该市全民健康信息平台中2017—2021年的居民电子健康档案信息,建立老年人健康体检自然人群队列。以该时间段内首次体检时间为基线,使用CMWI衡量老年人基线的慢性病共病负担,采用负二项回归分析个体基线的CMWI分别与其在随访时间内利用的总门诊次数、慢性病相关门诊次数、总住院次数以及慢性病相关住院次数的关联性。结果39989例老年人中,14991例(55.18%)患有慢性病共病,CMWI值为1.3(0,2.3);在平均1268 d随访时间内,26141例(65.37%)利用过门诊服务,总门诊次数为2(0,6)次,慢性病相关门诊次数为1(0,4)次;7332例(18.34%)利用过住院服务,总住院次数为0(0,0)次,慢性病相关住院次数为0(0,0)次。不同年龄、性别、文化程度及CMWI的老年人卫生服务利用比较,差异有统计学意义(P0.05)。在调整年龄、性别、居住地、文化程度后,负二项回归分析结果显示,CMWI是老年人卫生服务利用次数增加的危险因素(IRR>1),CMWI每增加1个单位,总门诊次数增加1.210次(95%CI=1.196~1.224次),慢性病相关门诊次数增加1.276次(95%CI=1.259~1.292次),总住院次数增加1.277次(95%CI=1.244~1.312次),慢性病相关住院次数增加1.286次(95%CI=1.252~1.321次)。结论CMWI是老年人卫生服务利用次数增加的危险因素,老年人卫生服务利用次数随CMWI值增大而增加,应重视老年人的慢性病共病负担,为改进我国老年人慢性病共病干预与管理提供科学依据。

关键词：慢性病共病老年人卫生服务利用负二项回归中国共病加权指数

Conceptual design and control method for a noncontact annular electromagnetic stabilized satellite platform

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第1期37卷 256-270页

作者： He liao Daixin WANG yuan REN Weijie WANG Institute of Astronautics Nanjing University of Aeronautics and AstronauticsNanjing 211106China Department of Basic Course Space Engineering UniversityHuairou DistrictBeijing 101416China

Disturbance-Free Payload(DFP)spacecraft can meet the requirements of ultra-high attitude pointing accuracy and stability for future space ***,as the main control actuators of DFP spacecraft,Linear Non-Contact Lorentz Actuators(LNCLAs)have control output problems with six-degree-of-freedom coupling and nonlinear effects,which will affect the attitude control performance of DFP *** solve this problem,a novel concept for Non-Contact Annular Electromagnetic Stabilized Satellite Platform(NCAESSP)is proposed in this *** concept is centered on replacing the LNCLAs with a non-contact annular electromagnetic actuator to solve the two problems mentioned ***,for the different control requirements of the payload module and the support module of the NCAESSP,a high-precision attitude controller based on the robust model matching method and a dual quaternion-based adaptive sliding mode controller are ***,the simulation results verify the feasibility and effectiveness of the proposed approach.

关键词： Disturbance-free payload Robust model matching Dual quaternion Sliding mode control Collision avoidance

The altered expression of inflammation-related microRNAs with microRNA-155 expression correlates with Th17 differentiation in patients with acute coronary syndrome

在线全文

学校读者我要写书评

暂无评论

Cellular & Molecular Immunology 2011年第6期8卷 486-495页

作者： Rui Yao Yulan Ma Youyou Du Mengyang liao Huanhuan Li Wei Liang jing yuan Zhijun Ma Xian Yu Hong Xiao Yuhua liao Laboratory of Cardiovascular Immunology Institute of CardiologyUnion HospitalHuazhong University of Science and TechnologyWuhanChina Department of Cardiology the First Affiliated Hospital of Zhengzhou UniversityZhengzhouChina Department of General Surgery Union HospitalHuazhong University of Science and TechnologyWuhanChina Pharmaceutical Preparation Section the First Hospital of Wuhan CityWuhanChina

MicroRNAs(miRNAs)are a novel class of small,non-coding RNAs that play a significant role in both inflammatory and cardiovascular *** cells,especially T helper(Th)cells,are critical in the development of atherosclerosis and the onset of acute coronary syndrome(ACS).To assess whether inflammation-related miRNAs(such as miR-155,146a,21,125a-5p,125b,31)are involved in the imbalance of Th cell subsets in patients with ACS,we measured the expression of related miRNAs in patients with acute myocardial infarction(AMI),unstable angina(UA),stable angina(SA)and chest pain syndrome(CPS);analyzed the relationship between miRNA expression and the frequency of Th cell subsets;and observed the co-expression of miR-155 and IL-17A in peripheral blood mononuclear cells(PBMCs)of patients with *** results showed that the expression of miR-155 in the PBMCs of patients with ACS was decreased by approximately 60%,while the expression of both miR-21 and miR-146a was increased by approximately *** expression patterns of miRNAs in plasma correlated with those in PBMCs,except for miR-21,which was increased by approximately sixfold in the AMI group and showed no significant difference between the UA group and the CPS *** also found that the expression of miR-155 inversely correlated with the frequency of Th17 cells(r520.896,P,0.01)and that miR-155 was co-expressed with IL-17A in patients with *** conclusion,our study revealed the expression patterns of inflammation-related miRNAs in patients with ACS and found that miR-155 may be associated with Th17 cell differentiation.

关键词： acute coronary syndrome microRNA-155 Th17

Cross-linked lipoic acid nanocapsules serve as H_(2)O_(2) amplifier to strengthen the H_(2)O_(2)-sensitive prodrug activation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2023年第9期66卷 2654-2663页

作者： Jiangbing Tan Pei jing Xiao Xiao Yulong liao Chunyan liao Shiyong Zhang College of Biomedical Engineering and National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610064China Department of Pharmacy the Affiliated Hospital of Southwest Medical UniversityLuzhou 646000China

The H_(2)O_(2) -triggered prodrug activation represents a hot topic while the low H_(2)O_(2) level of cancer cells hindered the complete activation of parent drugs and resulted in the poor therapeutic effect. Here, we developed an H_(2)O_(2) amplifier fabricated by crosslinked lipoic acid nanocapsules(cLANCs), which would selectively elevate the intracellular H_(2)O_(2) level of cancer cells 3.4-fold higher than that of untreated cancer cells so as to speed up the activation of parent drug from the loaded prodrugs(Pro-5-FU). The cytotoxicity showed that the killing effect of Pro-5-FU loaded in cLANCs(Pro-5-FU@cLANCs) arrived up to 1.6-time higher than that of Pro-5-FU alone against A549 cells, and was even close to free 5-FU. The in vivo anticancer evaluation gave the tumor inhibition rate(TIR) and survival rate(SR) of Pro-5-FU@cLANCs against A549 tumor-bearing nude mice up to 73.1% and 80%,respectively, much higher than those of Pro-5-FU(TIR: 41.2%, SR: 20%) or free 5-FU(TIR: 50.6%, SR: 0%). This nanodrug constructed the first example that utilizes the drug carriers as H_(2)O_(2) amplifier to strengthen the prodrug activation.

关键词： cancer therapy prodrug activation H_(2)O_(2)amplifier drug carrier

Lipid homeostasis and the formation of macrophage-derived foam cells in atherosclerosis

在线全文

学校读者我要写书评

暂无评论

Protein & Cell 2012年第3期3卷 173-181页

作者： yuan yuan Peng Li jing Ye Department of Pathology Xijing HospitalFourth Military Medical UniversityXi'an 710032China Tsinghua-Peking Center for Life Sciences School of Life SciencesTsinghua UniversityBeijing 100084China

Atherosclerosis is a chronic,inflammatory disorder characterized by the deposition of excess lipids in the arterial *** formation of macrophage-derived foam cells in a plaque is a hallmark of the development of *** homeostasis,especially cho-lesterol homeostasis,plays a crucial role during the formation of foam ***,lipid droplet-associated proteins,including PAT and CIDE family proteins,have been shown to control the development of athero-sclerosis by regulating the formation,growth,stabiliza-tion and functions of lipid droplets in macrophage-derived foam *** review focuses on the potential mechanisms of formation of macrophage-derived foam cells in atherosclerosis with particular emphasis on the role of lipid homeostasis and lipid droplet-associated *** the process of foam cell for-mation will aid in the future discovery of novel thera-peutic interventions for atherosclerosis.

关键词： macrophage foam cell atherosclerosis cholesterol lipid droplet-associated proteins