检索结果-南通市图书馆

维普期刊数据库博看期刊

Aerial refueling scheduling of multi-receiver and multi-tanker under spatial-temporal constraints for forest firefighting

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第5期37卷 71-91,I0001页

作者： Jing HUANG Jiaqi xing Jinrui REN quan quan Youmin ZHANG Department of Information and Control Engineering Xi’an University of TechnologyXi’an 710048China Jiujiang Measuring Test Technology Research Institute Jiujiang 332000China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China School of Automation Xi’an University of Posts&TelecommunicationsShaanxiXi’an 710121China Department of Mechanical Industrial and Aerospace EngineeringConcordia UniversityMontreal H3G 1M8Canada

Forest fires pose a significant threat to human life and property,so the utilization of unmanned aircraft systems provides new ways for forest *** the constrained load capacities of these aircraft,aerial refueling becomes crucial to extend their operational time and *** order to address the complexities of firefighting missions involving multi-receiver and multi-tanker deployed from various airports,first,a fuel consumption calculation model for aerial refueling scheduling is established based on the receiver ***,two distinct methods,including an integrated one and a decomposed one,are designed to address the challenges of establishing refueling airspace and allocating tasks for *** methods aim to optimize total fuel consumption of the receivers and tankers within the aerial refueling scheduling *** optimization problem is established as nonlinear optimization models along with *** integrated method seamlessly combines refueling rendezvous point scheduling and tanker task allocation into unified *** has a complete solution space and excels in optimizing total fuel *** decomposed method,through the separation of rendezvous point scheduling and task allocation,achieves a reduced computational ***,this comes at the cost of sacrificing optimality by excluding specific feasible ***,numerical simulations are carried out to verify the feasibility and effectiveness of the proposed *** simulations yield insights crucial for the practical engineering application of both the integrated and decomposed methods in real-world *** comprehensive approach aims to enhance the efficiency of forest firefighting operations,mitigating the risks posed by forest fires to human life and property.

关键词： Aerial refueling Scheduling Planning Spatial-temporal constraint Firefighting

Dynamic plugging regulating strategy of pipeline robot based on reinforcement learning

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第1期21卷 597-608页

作者： xing-Yuan Miao Hong zhao College of Mechanical and Transportation Engineering China University of PetroleumBeijing102249China

Pipeline isolation plugging robot (PIPR) is an important tool in pipeline maintenance operation. During the plugging process, the violent vibration will occur by the flow field, which can cause serious damage to the pipeline and PIPR. In this paper, we propose a dynamic regulating strategy to reduce the plugging-induced vibration by regulating the spoiler angle and plugging velocity. Firstly, the dynamic plugging simulation and experiment are performed to study the flow field changes during dynamic plugging. And the pressure difference is proposed to evaluate the degree of flow field vibration. Secondly, the mathematical models of pressure difference with plugging states and spoiler angles are established based on the extreme learning machine (ELM) optimized by improved sparrow search algorithm (ISSA). Finally, a modified Q-learning algorithm based on simulated annealing is applied to determine the optimal strategy for the spoiler angle and plugging velocity in real time. The results show that the proposed method can reduce the plugging-induced vibration by 19.9% and 32.7% on average, compared with single-regulating methods. This study can effectively ensure the stability of the plugging process.

关键词： Pipeline isolation plugging robot Plugging-induced vibration Dynamic regulating strategy Extreme learning machine Improved sparrow search algorithm Modified Q-learning algorithm

Relationship of Retinal Nerve Fiber Layer Thickness and Retinal Vessel Calibers with Cognitive Impairment in the Asymptomatic Polyvascular Abnormalities Population

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2024年第2期37卷 196-203页

作者： WANG Dan Dan WANG An Xin ZHANG Xiao Li WEI Wen Bin WU Shou Ling zhao xing quan Department of Neurology Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China China National Clinical Research Center for Neurological Diseases Beijing 100070China Beijing Tongren Eye Center Beijing Key Laboratory of Ophthalmology and Visual ScienceBeijing Tongren HospitalCapital Medical UniversityBeijing 100005China Department of Cardiology Kailuan HospitalTangshan 063001HebeiChina

Objective Cognitive impairment(CI)in older individuals has a high morbidity rate worldwide,with poor diagnostic methods and susceptible population *** study aimed to investigate the relationship between different retinal metrics and CI in a particular population,emphasizing polyvascular *** We collected information from the Asymptomatic Polyvascular Abnormalities Community Study on retinal vessel calibers,retinal nerve fiber layer(RNFL)thickness,and cognitive function of 3,785participants,aged 40 years or *** regression was used to analyze the relationship between retinal metrics and cognitive *** stratified by different vascular statuses were also *** RNFL thickness was significantly thinner in the CI group(odds ratio:0.973,95%confidence interval:0.953–0.994).In the subgroup analysis,the difference still existed in the non-intracranial arterial stenosis,non-extracranial carotid arterial stenosis,and peripheral arterial disease subgroups(P<0.05).Conclusion A thin RNFL is associated with CI,especially in people with non-large vessel *** underlying small vessel change in RNFL and CI should be investigated in the future.

关键词： Retinal nerve fiber layer Cognitive impairment Polyvascular abnormality

Interference-induced suppression of particle emission from a Bose-Einstein condensate in lattice with time-periodic modulations

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第10期33卷 153-158页

作者： Long-quan Lai zhao Li School of Science Nanjing University of Posts and TelecommunicationsNanjing 210023China School of Electronic Engineering Chengdu Technological UniversityChengdu 611730China

Emission of matter-wave jets from a parametrically driven condensate has attracted significant experimental and theoretical attention due to the appealing visual effects and potential metrological *** this work,we investigate the collective particle emission from a Bose-Einstein condensate confined in a one-dimensional lattice with periodically modulated interparticle *** give the regimes for discrete modes,and find that the emission can be distinctly *** configuration induces a broad band,but few particles are ejected due to the interference of the matter *** further qualitatively model the emission process and demonstrate the short-time *** engineering provides a way to manipulate the propagation of particles and the corresponding dynamics of condensates in lattices,and may find application in the dynamical excitation control of other nonequilibrium problems with time-periodic driving.

关键词： Bose-Einstein condensate matter-wave jet periodic modulation

A Comparison of Brain Death Criteria between China and the United States

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2015年第21期128卷 2896-2901页

作者： Ze-Yu Ding Qian Zhang Jian-Wei Wu Zhong-Hua Yang xing-quan zhao Department of Neurology Beijing Tiantan Hospital Capital Medical University China National Clinical Research Center for Neurological Diseases Center of Stroke Beijing Institute for Brain Disorders Beijing Key Laboratory of Translational Medicine for Cerebrovascular Disease Beijing 100050 China

Background： Criteria for determining brain death （BD） vary between China and the United States. We reported the results of an investigation designed to compare procedures to determine BD in two countries. Methods： The latest criteria in the United states were published in 2010. The latest criteria in China were published in 2009. We used these two types of BD criteria to evaluate patients who were considered to be BD. The time, cost, and accuracy of the diagnosis were compared. Results： From January 1, 2012 to October 8, 2013, there were 37 patients which were applied for BD evaluation in the Neurological Intensive Care Unit of Beijing Tiantan Hospital. The cause of coma were known as subarachnoid hemorrhage （18 patients, 48.6%）, intracerebral hemorrhage （8 patients, 21.6%）, cerebral ischemia （9 patients, 24.3%）, brain stem tumor （1 patient, 2.7%）, and intracranial infection （1 patient, 2.7%）. The clinical examinations were done for all of the patients except 1 patient who had low blood pressure. Three patients had hrainstem reflexes that were excluded from BD. Twenty-five patients had apnea tests, and 20 tests were completed that were all positive. Confirmatory tests were completed differently： Transcranial Doppler （30 patients, positive rate 86.7%）, electroencephalogram （25 patients, positive rate 100%）, and somatosensory evoked potential （16 patients, positive rate 100%）. Thirty-three patients were diagnosed BD by criteria of the United States. Only 9 patients were diagnosed BD by Chinese criteria. The use of time and money in the USA criteria was obviously fewer than those in Chinese criteria （P = 0.000）. Conclusion： Compared with BD criteria of the United States, Chinese criteria were stricter, lower positive rate, more cost in money and time, and more reliable by families and doctors.

关键词： Apnea Test Brain Death Criteria China Diagnosis the United States

Link between periodontitis and diabetic retinopathy:Inflammatory pathways and clinical implications

在线全文

学校读者我要写书评

暂无评论

World Journal of Diabetes 2024年第9期15卷 1842-1846页

作者： Yu zhao quan-quan Shen Geriatric Medicine Center Department of EndocrinologyZhejiang Provincial People’s Hospital(Affiliated People’s Hospital)Hangzhou Medical CollegeHangzhou 310014Zhejiang ProvinceChina Urology and Nephrology Center Department of NephrologyZhejiang Provincial People’s Hospital(Affiliated People’s HospitalHangzhou Medical College)Hangzhou 310014Zhejiang ProvinceChina Department of Nephrology Zhejiang Provincial People’s Hospital Bijie HospitalBijie 551700Guizhou ProvinceChina

The bidirectional relationship between periodontitis and type 2 diabetes mellitus has been ***,the underlying molecular mechanisms remain *** retinopathy(DR)is an important complication of diabetes,but there are few studies on the relationship between DR and periodontitis,especially on the intrinsic inflammatory pathway *** article reviews the latest clinical data on how diabetes promotes susceptibility to periodontitis from the epidemiological and molecular perspectives,with a special focus on the key roles of systemic inflammation and endothelial dysfunction in the interplay between DR and *** of the intertwined pathogenesis of DR and periodontitis can better guide the development of comprehensive management strategies for glycemic control and periodontal health,with the aim of mitigating the progression of DR and enhancing overall well-being.

关键词： Type 2 diabetes mellitus Diabetic retinopathy Microvascular complications Periodontitis Systemic inflammation Endothelial dysfunction

Accelerated Primal-Dual Projection Neurodynamic Approach With Time Scaling for Linear and Set Constrained Convex Optimization Problems

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

IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1485-1498页

作者： You zhao xing He Mingliang Zhou Tingwen Huang Chongqing Key Laboratory of Nonlinear Circuits and Intelligent Information Processing College of Electronic and Information EngineeringSouthwest UniversityChongqing 400715China School of Computer Science Chongqing UniversityChongqing 400044China Department of Mathematics Texas A&M University at QatarDoha 23874Qatar IEEE

The Nesterov accelerated dynamical approach serves as an essential tool for addressing convex optimization problems with accelerated convergence *** previous studies in this field have primarily concentrated on unconstrained smooth con-vex optimization *** this paper,on the basis of primal-dual dynamical approach,Nesterov accelerated dynamical approach,projection operator and directional gradient,we present two accelerated primal-dual projection neurodynamic approaches with time scaling to address convex optimization problems with smooth and nonsmooth objective functions subject to linear and set constraints,which consist of a second-order ODE(ordinary differential equation)or differential conclusion system for the primal variables and a first-order ODE for the dual *** satisfying specific conditions for time scaling,we demonstrate that the proposed approaches have a faster conver-gence *** only requires assuming convexity of the objective *** validate the effectiveness of our proposed two accel-erated primal-dual projection neurodynamic approaches through numerical experiments.

关键词： Accelerated projection neurodynamic approach lin-ear and set constraints projection operators smooth and nonsmooth convex optimization time scaling.

Design and synthesis of thiol-terminated imidothioether oligomer as thermally latent hardener and modifier for high-performance epoxy/thiol thermosets

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第2期67卷 632-641页

作者： xing Liu Jianjun Zhou Shumei Liu Jianqing zhao School of Materials Science and Engineering South China University of TechnologyGuangzhou510640China Key Lab Guangdong High Property&Functional Polymer Materials Key Laboratory of Polymer Processing EngineeringMinistry of EducationGuangzhou510640China

Conventional base-catalyzed epoxy/aliphatic thiol systems have a poor storage stability,and are impossible to be one-pot systems.A widely accepted solution is to use the latent catalysts,which are usually insoluble anionic initiators sensitive to impurities and moisture,and have many limitations in practical *** this work,a soluble thiol-terminated imidothioether oligomer(TPI) was synthesized and used as a latent hardener and modifier to prepare one-pot epoxy/thiol systems without the latent *** latent behavior and curing mechanism of epoxy systems(EP/TPI series),consisted of bisphenol A diglycidyl ether(DGEBA),pentaerythritol tetrakis(mercaptoacetate)(PETMP) and TPI,were *** thiol exchange reaction between TPI and PETMP preceded the curing reaction of DGEBA,and produced aromatic thiols,which were unreactive at ambient conditions and reacted with DGEBA to form the thermosets at temperatures above 130 ℃.At the loading of 24.4 wt%TPI,the epoxy system(EP/TPI-3) had a shelf life of 13 days and was completely cured within 20 min at 180 ℃.Meanwhile,the catalyst-free curing process of EP/TPI-3 system was insensitive to impurities and ***,the thermal and mechanical properties of EP/TPI-3 thermoset were simultaneously improved,thereinto,the glass transition temperature,Young's modulus and ultimate tensile strength were increased by 16.7 ℃,12.9%,and 13.6%,respectively,compared with those of the commercial DGEBA/PETMP *** work shows that TPI has the potential to be a powerful alternative to commercial latent catalysts,and EP/TPI thermosets with high performance have broad application prospects.

关键词： thiol-terminated imidothioether oligomer epoxy systems thiol exchange reaction thermal latency high performance

Multidisciplinary experts consensus for assessment and management of vestibular migraine

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2019年第2期132卷 183-189页

作者： Stroke and Vertigo Association of Chinese Stroke Association Xiao-Kun Qi xing-quan zhao 不详 Department of Neurology the Sixth Medical CenterChinese PLA General HospitalBeijing 100048China Department of Neurology Tiantan Hospital of Capital Medical UniversityBeijing 100050China

Introduction Vestibular migraine (VM), a common disorder with familiar predisposition, is characterized by recurrent episode of dizziness or vertigo and accompanying symptoms of nausea, vomiting, and/or *** patients with VM may require neurologic, emergency, or otorhinolaryngologic services, and the disorder is often misdiagnosed with posterior circulation ischemia (PCI) or transient ischemic attack (TIA), peripheral vestibular vertigo, Meniere’s disease (MD), and multiple (lacunar) cerebral *** from population-based study showed that the prevalence of VM was up to 1%,^[1] which was one of the common disorders causing dizziness/vertigo, and the rate of misdiagnosis was up to 80%.[2] Thus, a multidisciplinary expert consensus about the definition, characteristics, related work-ups, and diagnostic criteria is needed for the accurate diagnosis and standardized management.

关键词： Introduction Vestibular familiar predisposition characterized