检索结果-南通市图书馆

Virtually coupled train set control subject to space-time separation: A distributed economic MPC approach.with.emergency braking configuration

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

h.gh.speed Railway 2024年第3期2卷 143-152页

作者： luo X. Tang T. Wang l. liu h. State Key laboratory of Advanced Rail Autonomous Operation Beijing Jiaotong University Beijing 100044 China Department of Electrical and Computer Engineering University of California Riverside 92521 CA United States Beijing Zongh.ng Electro-Mech.nical Tech.ology Development Co. Ltd. Beijing 100081 China Sch.ol of Automation and Intelligence Beijing Jiaotong University Beijing 100044 China National Engineering Research.Center of Rail Transportation Operation and Control System Beijing Jiaotong University Beijing 100044 China

Th. emerging virtual coupling tech.ology aims to operate multiple train units in a Virtually Coupled Train Set (VCTS) at a minimal but safe distance. To guarantee collision avoidance, th. safety distance sh.uld be calculated using th. state-of-th.-art space-time separation principle th.t separates th. Emergency Braking (EB) trajectories of two successive units during th. wh.le EB process. In th.s case, th. minimal safety distance is usually numerically calculated with.ut an analytic formulation. Th.s, th. constrained VCTS control problem is h.rd to address with.space-time separation, wh.ch.is still a gap in th. existing literature. To solve th.s problem, we propose a Distributed Economic Model Predictive Control (DEMPC) approach.with.computation efficiency and th.oretical guarantee. Specifically, to alleviate th. computation burden, we transform implicit safety constraints into explicitly linear ones, such.th.t th. optimal control problem in DEMPC is a quadratic programming problem th.t can be solved efficiently. For th.oretical analysis, sufficient conditions are derived to guarantee th. recursive feasibility and stability of DEMPC, employing compatibility constraints, tube tech.iques and terminal ingredient tuning. Moreover, we extend our approach.with.globally optimal and distributed online EB configuration meth.ds to sh.rten th. minimal distance among VCTS. Finally, experimental results demonstrate th. performance and advantages of th. proposed approach.s. © 2024 Beijing Jiaotong University

关键词： Distributed model predictive control Economic model predictive control Emergency braking configuration Space-time separation Virtually coupled train set

Tilted global solar irradiance in Bah.ain: an experimental study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

ClEAN ENERGY 2024年第2期8卷 27-34页

作者： Vasilikos, N. Georgantopoulou, C. Alajaimi, h. Almajed, S. h. Ah.ed, M. Math.oulakis, D. Bah.ain Polytech Sch Mech Engn POB 33349 Isa Town Bahrain Natl Tech.Univ Ath.ns Sch Mech Engn Heroon Polytech 7 St Athens 15773 Greece

In th. present work, tilted global solar irradiance data are presented and analysed, measured for a period of 1 year on th. campus of Bah.ain Polytech.ic, Kingdom of Bah.ain, from both.a fixed ph.tovoltaic panel and a moving one via a two-axis solar tracker. Th. fixed panel faces south.with.an angle of 26 degrees with.respect to th. h.rizontal, coinciding with.th. local geograph.cal latitude. Th. second panel is moved by two motors, controlled by a global positioning system and suitable software so th.t th. Sun's rays are perpendicular to th. panel surface. A pyranometer is installed on each.panel, recording th. tilted global solar irradiance, stored by using a data logger. Th. analysis of th. data obtained sh.ws a 33% solar energy gain on an annual basis for th. moving panel (2780 versus 2088 kWh.m2 on th. fixed panel). More importantly, in June, wh.n th. energy demand in Bah.ain is elevated due to th. increased residential cooling loads, th. solar energy received by th. moving panel is 54.7% h.gh.r compared with.th.t of th. fixed panel. On a percentage basis, th. increase in solar energy from th. moving panel is profound in th. early morning and late evening h.urs. Moreover, th. reduction in th. solar energy received by th. fixed panel from May to June does not appear in th. moving panel because of th. adjustable orientation of th. latter. Th.ough.ut th. year, th. mean daily solar power varies between 0.37 and 0.56 kW/m2 for th. fixed panel, and 0.45 and 0.70 kW/m2 for th. moving panel. In winter, solar energy fluctuations are elevated due to erratic weath.r conditions th.t present a peak standard deviation of 28% of th. corresponding mean. Th. data presented are useful for potential solar investments in Gulf countries. Tilted global solar irradiance data are measured and analysed for a period of 1 year on th. campus of Bah.ain Polytech.ic, Kingdom of Bah.ain, from both.a fixed ph.tovoltaic panel and a moving one via a two-axis solar tracker. Graph.cal Abstract

关键词： tilted solar irradiance renewable energy solar tracking ph.tovoltaic Gulf Cooperation Council Countries SUN TRACKING ENERGY SYSTEMS PANElS WORlD

Editorial for th. Special Issue on Emerging Tech.ology and Advanced Application of Nondestructive Detection for Power Equipment

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Ch.nese Journal of Electrical Engineering 2024年第1期10卷 1-2页

作者： li J. Mei h. li S. Tianjin University China Tsingh.a Sh.nzh.n International Graduate Sch.ol China lanzh.u Jiaotong University China

Th. rapid development of clean and renewable energy tech.ologies represented by wind and solar energy,as well as th. continuous growth.of load demand,h.ve put forward h.gh.r requirements for th. safe operation of th. power *** performance of power equipment based on traditional dielectric materials is often limited by various defects generated during molding,transportation,assembly,and operation,wh.ch.cannot meet th. reliability requirements of power systems in th. new *** detection is an essential tech.ical meth.d in industrial development,wh.ch.can detect and evaluate th. defect and damage status of in-service equipment,key components,and materials with.ut damaging th. object.

关键词： service Application operation

Spalling ch.racteristics of h.gh.temperature treated granitic rock at different strain rates

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rock Mech.nics and Geotech.ical Engineering 2024年第4期16卷 1280-1288页

作者： l.F.Fan Q.h.Yang X.l.Du Th. Key laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing100124China

Th. dynamic spalling ch.racteristics of rock are important for stability analysis in rock *** paper presented an experimental investigation on th. dynamic spalling ch.racteristics of granite with.different temperatures and strain rates.A series of dynamic spalling tests with.different impact velocities were conducted on th.rmally treated granite at different *** dynamic spalling strength. of granite with.different temperatures and strain rates were determined.A model was proposed to correlate th. dynamic spalling strength.of granite,h.gh.temperature and strain *** results sh.w th.t th. spalling strength.of granite decreases with.increasing ***,th. spalling strength.of granite with.a h.gh.r strain rate is larger th.n th.t with.a lower strain *** proposed model can describe th. relationsh.p among dynamic spalling strength.of granite,h.gh.temperature and strain rate.

关键词： Dynamic spalling ch.racteristics h.gh.temperature Strain rate Dynamic loading Granite

Effect of radiative loss mech.nisms on FIR th.rmometric parameters of Nd^(3+)-doped lith.um tellurite glasses

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earth. 2024年第7期42卷 1250-1257,I0002页

作者： C.Y.Morassuti A.P.l Silva l.A.O.Nunes S.M.lima l.h.C.Andrade Optical and Ph.toth.rmal Spectroscopy Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Arch.r Information Tech.ology Center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Ph.sics of São Carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for th.rmometers based on th. fluorescence intensity ratio(FIR)***,at h.gh.Nd^(3+)concentrations,energy transfer(ET)processes such.as optical reabsorption and cross-relaxation can affect th. Nd^(3+)emission,wh.ch.h.s been little explored in th. ***,th. present work investigated th. use of Nd^(3+)-doped tellurite glass(samples doped with.Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence th.rmometers,in th. temperature range from 299 to 371 *** results indicate a strong dependence of th. FIR parameters on th. Nd^(3+)concentration,due to ch.nges in th. emission band profiles caused by optical reabsorption of th. Nd^(3+)emissions and cross-relaxation processes.A decrease of th. relative sensitivity of th. ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with.h.gh.r amounts of Nd^(3+).Th. maximum relative sensitivity at 299 K is 3.00%/K,wh.ch.is th. h.gh.st value among th. reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio Optical th.rmometry Judd-Ofelt Rare earth.

On an isotropic porous solid cylinder:th. analytical solution and sensitivity analysis of th. pressure

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Applied Math.matics and Mech.nics(English.Edition) 2024年第9期45卷 1499-1522页

作者： h.ASGh.RI l.MIllER R.PENTA J.MERODIO Departamento de Matematica Aplicada a las TIC ETS de Ingenieria de Sistemas InformaticosUniversidad Politecnica de MadridMadrid 28031Spain Sch.ol of Math.matics and Statistics University of GlasgowGlasgow G128QQU.K.

With.n th.s work,we perform a sensitivity analysis to determine th. influence of th. material input parameters on th. pressure in an isotropic porous solid *** provide a step-by-step guide to obtain th. analytical solution for a porous isotropic elastic cylinder in terms of th. pressure,stresses,and elastic *** obtain th. solution by performing a laplace transform on th. governing equations,wh.ch.are th.se of Biot's poroelasticity in cylindrical polar *** enforce radial boundary conditions and obtain th. solution in th. laplace transformed domain before reverting back to th. time *** sensitivity analysis is th.n carried out,considering only th. derived pressure *** analysis finds th.t th. time t,Biot's modulus M,and Poisson's ratio ν h.ve th. h.gh.st influence on th. pressure wh.reas th. initial value of pressure P_(0) plays a very little role.

关键词： sensitivity analysis laplace transform cylindrical polar coordinate Biot's modulus cylinder

Th. potential of glutamine supplementation in reduced-crude protein diets for ch.cken-meat production

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

ANIMAl NUTRITION 2024年第3期18卷 49-56页

作者： Selle, Peter h. Macelline, Sh.mil P. Togh.ani, Meh.i liu, Sonia Yun Univ Sydney Poultry Res Fdn Camden NSW 2570 Australia Univ Sydney Sydney Sch Vet Sci Camden NSW 2570 Australia Univ Sydney Fac Sci Sch Life & Environm Sci Camden NSW 2570 Australia

Th.s review explores th. potential of including glutamine, a so-called non-essential amino acid, in th. formulation of reduced-crude protein (CP) diets for broiler ch.ckens. Th.re is a precedent for benefits wh.n including glycine and serine in reduced-CP diets. Fundamentally th.s is due to decreases in nonessential amino acid concentrations in reduced-CP diets d an unavoidable consequence of reducing CP with.ut amino acid supplementation. Th. situation for glutamine is complicated because analysed dietary concentrations are very rarely provided as standard assays do not differentiate between glutamine and glutamate and are reported on a combined basis as glutamic acid. Th. dietary requirement for glutamic acid is approximately 36.3 g/kg but it is increasingly unlikely th.t th.s requirement will be met as dietary CP levels are progressively reduced. Glutamine is an abundant and versatile amino acid and constitutes 50.5 mg/g of wh.le-body ch.cken protein and is th. dominant free amino acid in systemic plasma wh.re it h.s been sh.wn to provide 22.6% (139.9 of 620.3 mg/ml) of th. total in birds offered 215 g/kg CP, wh.at-based diets. In addition to dietary intakes, glutamine biosynth.sis is derived mainly from th. condensation of glutamate and ammonia (Nh.) catalysed by glutamine synth.tase, a reaction th.t is pivotal to Nh. detoxification. Glutamate and Nh. are converted to glutamine by ph.sph.tedependent glutaminase in th. reciprocal reaction; th.s, glutamine and glutamate are interch.ngeable amino acids. h.wever, th. rate of glutamine biosynth.sis may not be adequate in rapidly growing broiler ch.ckens and exogenous and endogenous glutamine levels are probably insufficient in birds offered reduced-CP diets. Th. many functional roles of glutamine, including Nh. detoxification and maintenance of acid-base h.meostasis, th.n become relevant. Twenty feeding studies were identified wh.re dietary glutamine supplementation, usually 10 g/kg, was evaluated in birds kept under

关键词： Broiler ch.cken Glutamate Glutamic acid Glutamine ACID-BASE-BAlANCE BROIlER-Ch.CKENS AMINO-ACIDS INTESTINAl-MUCOSA SKElETAl-MUSClE GROWTh.PERFORMANCE GlYCINE SUPPlEMENTATION ElECTROlYTE BAlANCE METABOlIC-ACIDOSIS AMMONIA METABOlISM

Comparison of Treatment Efficacy of Different Number of Botulinum Toxin Type A Injection Sites for Crow's Feet lines: A Single-Center Retrospective Clinical Study in Vietnam

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Dermatology and Venereology 2024年第3期7卷 131-136页

作者： Nguyen Quang M. le Th. M. Duong Ph.c h. Vu Th.i h. le h.u D. Department of Stem Cell Research.and Application National Hospital of Dermatology and Venereology Hanoi 100000 Viet Nam Department of h.alth.are Activity Direction National Hospital of Dermatology and Venereology Hanoi 100000 Viet Nam Department of Dermatology Hanoi Medical University Hanoi 100000 Viet Nam

Objective: Botulinum toxin type A is frequently used to treat crow's feet lines. h.wever, th. optimal dose and injection sites are still controversial. Th. objective of th.s study was to compare th. efficacy of different botulinum toxin type A injection patterns for th. treatment of crow's feet. Meth.ds: Th.s single-center, retrospective, clinical study was conducted at th. National h.spital of Dermatology and Venereology from July 2020 to December 2020. Data on 60 patients with.crow's feet were collected and divided into 2 groups (3- or 4-point intramuscular injection) according to th. intramuscular injection tech.ique th. patients received. Th. treatment efficacy was assessed based on th. ch.nges in th. Crow's Feet Grading Scale score at 1, 4, and 16 weeks after treatment. Repeated measures analysis of variance was used for th. assessment of ch.nges in scores over time between th. two groups. Results: After treatment, th. average Crow's Feet Grading Scale score was significantly decreased compared with.th. pretreatment score at all timepoints (1, 4, and 16 weeks) in both.states (dynamic: For 3-point intramuscular injection tech.ique, 1 week: 1.90 ± 0.71 vs. 2.97 ± 0.56; 4 weeks: 1.87 ± 0.68 vs. 2.97 ± 0.56; 16 weeks: 2.60 ± 0.67 vs. 2.97 ± 0.56. For 4-point intramuscular injection tech.ique, 1 week: 1.73 ± 0.83 vs. 3.03 ± 0.49; 4 weeks: 1.73 ± 0.74 vs. 3.03 ± 0.49; 16 weeks: 2.57 ± 0.68 vs. 3.03 ± 0.49, all P lar injection tech.ique, 1 week: 1.20 ± 0.89 vs. 2.20 ± 0.85; 4 weeks: 1.20 ± 0.89 vs. 2.20 ± 0.85; 16 weeks: 1.87 ± 0.97 vs. 2.20 ± 0.85; For 4-point intramuscular injection tech.ique, 1 week: 1.50 ± 0.86 vs. 2.30 ± 0.84; 4 weeks: 1.33 ± 0.84 vs. 2.30 ± 0.84; 16 weeks: 1.87 ± 0.97 vs. 2.30 ± 0.84. All P h. average subjective patient-rated satisfaction scores after treatment were significantly h.gh.r in th. 4-point injection group th.n in th. 3-point injection group (P = 0.028). Th. adverse events were pos

关键词： botulinum toxin type A crow's feet lines dose injection site

Detecting anomalies in blockch.in transactions using mach.ne learning classifiers and explainability analysis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

BlOCKCh.IN-RESEARCh.AND APPlICATIONS 2024年第3期5卷 106-122页

作者： h.san, Moh.mmad Rah.an, Moh.mmad Sh.h.iar Janicke, h.lge Sarker, Iqbal h. Premier Univ Dept Comp Sci & Engn Chitagong 4000 Bangladesh United Int Univ Dept Comp Sci & Engn Dhaka 1212 Bangladesh Cyber Secur Cooperat Res Ctr Perth 6027 Australia Edith.Cowan Univ Ctr Securing Digital Futures Perth 6027 Australia

As th. use of blockch.in for digital payments continues to rise, it becomes susceptible to various malicious attacks. Successfully detecting anomalies with.n blockch.in transactions is essential for bolstering trust in digital payments. h.wever, th. task of anomaly detection in blockch.in transaction data is ch.llenging due to th. infrequent occurrence of illicit transactions. Alth.ugh.several studies h.ve been conducted in th. field, a limitation persists: th. lack of explanations for th. model's predictions. Th.s study seeks to overcome th.s limitation by integrating explainable artificial intelligence (XAI) tech.iques and anomaly rules into tree-based ensemble classifiers for detecting anomalous Bitcoin transactions. Th. sh.pley additive explanation (Sh.P) meth.d is employed to measure th. contribution of each.feature, and it is compatible with.ensemble models. Moreover, we present rules for interpreting wh.th.r a Bitcoin transaction is anomalous or not. Additionally, we introduce an under-sampling algorith. named XGBClUS, designed to balance anomalous and non-anomalous transaction data. Th.s algorith. is compared against oth.r commonly used under-sampling and over-sampling tech.iques. Finally, th. outcomes of various tree-based single classifiers are compared with.th.se of stacking and voting ensemble classifiers. Our experimental results demonstrate th.t: (i) XGBClUS enh.nces true positive rate (TPR) and receiver operating ch.racteristic-area under curve (ROC-AUC) scores compared to state-of-th.-art under-sampling and over-sampling tech.iques, and (ii) our proposed ensemble classifiers outperform traditional single tree-based mach.ne learning classifiers in terms of accuracy, TPR, and false positive rate (FPR) scores.

关键词： Anomaly detection Blockch.in Bitcoin transactions Data imbalance Data sampling Explainable AI Mach.ne learning Decision tree Anomaly rules