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A time-space network based international transportation scheduling problem incorporating CO_2 emission levels
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作者 Takashi IROHARA 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2010年第12期927-932,共6页
Environmental problems have received a great deal of attention in recent years.In particular,CO2 emissions worsen global warming and other environmental problems.The transport sector accounts for 20% of the total CO2 ... Environmental problems have received a great deal of attention in recent years.In particular,CO2 emissions worsen global warming and other environmental problems.The transport sector accounts for 20% of the total CO2 emissions.Therefore,the CO2 emission reduction of the transport sector is of great importance.In order to reduce emissions effectively,it is necessary to change the distribution and transportation processes.The purpose of this study is to minimize both the transportation costs and CO2 emissions during transportation.Our model considers a transportation scheduling problem in which loads are transported from an overseas production base to three domestic demand centers.The need for time-space networks arises naturally to improve the model.It is possible to know the distance carriers are moving,and also consider the timetables of carriers during transportation.Carrier choice,less-than carrier load,and domestic transportation among demand centers are considered as the three target areas to reduce CO2 emissions during the distribution process.The research model was formulated as a mixed integer programming (MIP) problem.It achieves cost reduction,and will contribute to improvement of the natural environment. 展开更多
关键词 time-space network TIMETABLE Transportation scheduling problem Mixed integer programming (MIP) problem Less-than carrier load
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A time-space network-based model for transportation service optimization of China Railway Express
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作者 Weichuan Yin Wenhu Hu +2 位作者 Xueting Yan Bo Peng Xiaoling Yang 《High-Speed Railway》 2024年第3期153-163,共11页
This paper describes the development and optimization plans for the China Railway Express(CR Express).As a new type of international land transport organization,CR Express has emerged with the continuous expansion of ... This paper describes the development and optimization plans for the China Railway Express(CR Express).As a new type of international land transport organization,CR Express has emerged with the continuous expansion of China toward European investment and trade,and in particular,has expanded with the continuous progress of the One Belt and One Road(OBOR)initiative.In addition to improving the service quality of CR Express,the operating costs must be reduced for developing“smart railways”that serve“smart cities”.We propose a dualobjective-based function mathematical optimization model;the satisfaction of the cargo owner is considered,and the timeliness,transportation capacity,and goods category constraints of CR Express transportation are designed.Moreover,we present the normalized equivalent method of the two-objective function of the model.Finally,a case study is conducted against the background of certain trains in the western corridor of CR Express to validate the effectiveness of the model and research methods proposed in this study. 展开更多
关键词 One Belt and One Road China Railway Express Transportation service Mathematical optimization time-space network
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Shrinking India:Visualizing time-space implication of introduction of semihigh-speed trains in India
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作者 Vimal Kumar Arulmozhi Shreyas P.Bharule 《High-Speed Railway》 2025年第2期93-104,共12页
Indian Railways have been the largest people moving transport infrastructure in India.Over the years the systems and trains have been upgraded resulting in both better passenger amenities and reduction in travel time.... Indian Railways have been the largest people moving transport infrastructure in India.Over the years the systems and trains have been upgraded resulting in both better passenger amenities and reduction in travel time.The newest addition is the Vande Bharat Express,a semi-high-speed train that was introduced in India in 2019.The train currently runs between 10 routes and has brought significant changes to India’s railway network.This article explores the introduction of Vande Bharat Express trains in India and its effects on the country’s interstation time-space shrinkage using cartographic techniques.The cartographic techniques like stepwise multidimensional scaling and interpolation using the distance cartogram plugin in QGIS are mainly used for generating the time-space maps for various speeds.The limitations of these techniques and the methods to overcome those limitations are also explored in this article. 展开更多
关键词 Vande Bharat trains Multidimensional scaling INTERPOLATION time-space Map distortion
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SPREADING SPEED FOR A TIME-SPACE PERIODIC EPIDEMIC MODEL IN DISCRETE MEDIA
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作者 Haiqin ZHAO 《Acta Mathematica Scientia》 2025年第3期1005-1018,共14页
This paper is devoted to investigating the spreading speed of a time-space periodic epidemic model with vital dynamics and standard incidence in discrete media. We establish the existence of the leftward and rightward... This paper is devoted to investigating the spreading speed of a time-space periodic epidemic model with vital dynamics and standard incidence in discrete media. We establish the existence of the leftward and rightward spreading speeds for the infective individuals, which can be used to estimate how fast the disease spreads. To overcome the difficulty arising from the lack of comparison principle for such time-space periodic nonmonotone systems, our proof is mainly based on constructing a series of scalar time-space periodic equations, establishing the spreading speeds for such auxiliary equations and using comparison methods. It may be the first work to study the spreading speed for time-space periodic non-monotone systems. 展开更多
关键词 spreading speed epidemic models time-space periodic habitats
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A traffic model of optical networks based on time-space complexity and traffic grooming
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作者 赵永利 《High Technology Letters》 EI CAS 2009年第2期198-202,共5页
This paper researched the traffic of optical networks in time-space complexity,proposed a novel traf-fic model for complex optical networks based on traffic grooming,designed a traffic generator GTS(gener-ator based o... This paper researched the traffic of optical networks in time-space complexity,proposed a novel traf-fic model for complex optical networks based on traffic grooming,designed a traffic generator GTS(gener-ator based on time and space)with 'centralized+distributed' idea,and then made a simulation in Clanguage.Experiments results show that GTS can produce the virtual network topology which can changedynamically with the characteristic of scaling-free network.GTS can also groom the different traffic andtrigger them under real-time or scheduling mechanisms,generating different optical connections.Thistraffic model is convenient for the simulation of optical networks considering the traffic complexity. 展开更多
关键词 optical networks traffic model time-space complexity scaling-free SELF-SIMILARITY traffic grooming
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Effective pure qP-wave equation and its numerical implementation in the time-space domain for 3D complicated anisotropic media
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作者 Shi-Gang Xu Xing-Guo Huang Li Han 《Petroleum Science》 2025年第4期1534-1547,共14页
Seismic anisotropy has been extensively acknowledged as a crucial element that influences the wave propagation characteristic during wavefield simulation,inversion and imaging.Transversely isotropy(TI)and orthorhombic... Seismic anisotropy has been extensively acknowledged as a crucial element that influences the wave propagation characteristic during wavefield simulation,inversion and imaging.Transversely isotropy(TI)and orthorhombic anisotropy(OA)are two typical categories of anisotropic media in exploration geophysics.In comparison of the elastic wave equations in both TI and OA media,pseudo-acoustic wave equations(PWEs)based on the acoustic assumption can markedly reduce computational cost and complexity.However,the presently available PWEs may experience SV-wave contamination and instability when anisotropic parameters cannot satisfy the approximated condition.Exploiting pure-mode wave equations can effectively resolve the above-mentioned issues and generate pure P-wave events without any artifacts.To further improve the computational accuracy and efficiency,we develop two novel pure qP-wave equations(PPEs)and illustrate the corresponding numerical solutions in the timespace domain for 3D tilted TI(TTI)and tilted OA(TOA)media.First,the rational polynomials are adopted to estimate the exact pure qP-wave dispersion relations,which contain complicated pseudo-differential operators with irrational forms.The polynomial coefficients are produced by applying a linear optimization algorithm to minimize the objective function difference between the expansion formula and the exact one.Then,the developed optimized PPEs are efficiently implemented using the finite-difference(FD)method in the time-space domain by introducing a scalar operator,which can help avoid the problem of spectral-based algorithms and other calculation burdens.Structures of the new equations are concise and corresponding implementation processes are straightforward.Phase velocity analyses indicate that our proposed optimized equations can lead to reliable approximation results.3D synthetic examples demonstrate that our proposed FD-based PPEs can produce accurate and stable P-wave responses,and effectively describe the wavefield features in complicated TTI and TOA media. 展开更多
关键词 Anisotropic media Wavefield extrapolation Pure qP-wave equation Optimization algorithm Finite-difference method time-space domain
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Network perspective on rumination and non-suicidal self-injury among adolescents with depressive disorders
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作者 Fang-Fang Zhang Rui Guo +3 位作者 Si-Lan Chen Wei Yang Xing-Li Liang Ming-Fang Ma 《World Journal of Psychiatry》 2026年第1期346-355,共10页
BACKGROUND Non-suicidal self-injury(NSSI)is common among adolescents with depressive disorders and poses a major public health challenge.Rumination,a key cognitive feature of depression,includes different subtypes tha... BACKGROUND Non-suicidal self-injury(NSSI)is common among adolescents with depressive disorders and poses a major public health challenge.Rumination,a key cognitive feature of depression,includes different subtypes that may relate to NSSI through distinct psychological mechanisms.However,how these subtypes interact with specific NSSI behaviors remains unclear.AIM To examine associations between rumination subtypes and specific NSSI behaviors in adolescents.METHODS We conducted a cross-sectional study with 305 hospitalized adolescents diagnosed with depressive disorders.The subjects ranged from 12-18 years in age.Rumi-nation subtypes were assessed using the Ruminative Response Scale,and 12 NSSI behaviors were evaluated using a validated questionnaire.Network analysis was applied to explore symptom-level associations and identify central symptoms.RESULTS The network analysis revealed close connections between rumination subtypes and NSSI behaviors.Brooding was linked to behaviors such as hitting objects and burning.Scratching emerged as the most influential NSSI symptom.Symptomfocused rumination served as a key bridge connecting rumination and NSSI.CONCLUSION Symptom-focused rumination and scratching were identified as potential intervention targets.These findings highlight the psychological significance of specific cognitive-behavioral links in adolescent depression and suggest directions for tailored prevention and treatment.However,the cross-sectional,single-site design limits causal inference and generalizability.Future longitudinal and multi-center studies are needed to confirm causal pathways and verify the generalizability of the findings to broader adolescent populations. 展开更多
关键词 Depressive disorders Adolescents network analysis RUMINATION Non-suicidal self-injury
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Investigating the potential mechanisms of Wenqing Yin against atopic dermatitis based on network pharmacology,experimental pharmacology,and molecular docking
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作者 Yi Wang Zhen Liu +3 位作者 Si-Man Li Lin Lin Wei Dai Meng-Yue Ren 《Traditional Medicine Research》 2026年第2期1-11,共11页
Background:Wenqing Yin(WQY)is a classic prescription used to treat skin diseases like atopic dermatitis(AD)in China,and the aim of this study is to investigate the therapeutic effects and molecular mechanisms of WQY o... Background:Wenqing Yin(WQY)is a classic prescription used to treat skin diseases like atopic dermatitis(AD)in China,and the aim of this study is to investigate the therapeutic effects and molecular mechanisms of WQY on AD.Methods:The DNFB-induced mouse models of AD were established to investigate the therapeutic effects of WQY on AD.The symptoms of AD in the ears and backs of the mice were assessed,while inflammatory factors in the ear were quantified using quantitative real-time-polymerase chain reaction(qRT-PCR),and the percentages of CD4^(+)and CD8^(+)cells in the spleen were analyzed through flow cytometry.The compounds in WQY were identified using ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS)analysis and the key targets and pathways of WQY to treat AD were predicted by network pharmacology.Subsequently,the key genes were tested and verified by qRT-PCR,and the potential active components and target proteins were verified by molecular docking.Results:WQY relieved the AD symptoms and histopathological injuries in the ear and back skin of mice with AD.Meanwhile,WQY significantly reduced the levels of inflammatory factors IL-6 and IL-1βin ear tissue,as well as the ratio of CD4^(+)/CD8^(+)cells in spleen.Additionally,a total of 142 compounds were identified from the water extract of WQY by UPLC-Orbitrap-MS/MS.39 key targets related to AD were screened out by network pharmacology methods.The KEGG analysis indicated that the effects of WQY were primarily mediated through pathways associated with Toll-like receptor signaling and T cell receptor signaling.Moreover,the results of qRT-PCR demonstrated that WQY significantly reduced the mRNA expressions of IL-4,IL-10,GATA3 and FOXP3,and molecular docking simulation verified that the active components of WQY had excellent binding abilities with IL-4,IL-10,GATA3 and FOXP3 proteins.Conclusion:The present study demonstrated that WQY effectively relieved AD symptoms in mice,decreased the inflammatory factors levels,regulated the balance of CD4^(+)and CD8^(+)cells,and the mechanism may be associated with the suppression of Th2 and Treg cell immune responses. 展开更多
关键词 Wenqing Yin atopic dermatitis mouse model UPLC-Orbitrap-MS/MS network pharmacology
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Combined Fault Tree Analysis and Bayesian Network for Reliability Assessment of Marine Internal Combustion Engine
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作者 Ivana Jovanović Çağlar Karatuğ +1 位作者 Maja Perčić Nikola Vladimir 《哈尔滨工程大学学报(英文版)》 2026年第1期239-258,共20页
This paper investigates the reliability of internal marine combustion engines using an integrated approach that combines Fault Tree Analysis(FTA)and Bayesian Networks(BN).FTA provides a structured,top-down method for ... This paper investigates the reliability of internal marine combustion engines using an integrated approach that combines Fault Tree Analysis(FTA)and Bayesian Networks(BN).FTA provides a structured,top-down method for identifying critical failure modes and their root causes,while BN introduces flexibility in probabilistic reasoning,enabling dynamic updates based on new evidence.This dual methodology overcomes the limitations of static FTA models,offering a comprehensive framework for system reliability analysis.Critical failures,including External Leakage(ELU),Failure to Start(FTS),and Overheating(OHE),were identified as key risks.By incorporating redundancy into high-risk components such as pumps and batteries,the likelihood of these failures was significantly reduced.For instance,redundant pumps reduced the probability of ELU by 31.88%,while additional batteries decreased the occurrence of FTS by 36.45%.The results underscore the practical benefits of combining FTA and BN for enhancing system reliability,particularly in maritime applications where operational safety and efficiency are critical.This research provides valuable insights for maintenance planning and highlights the importance of redundancy in critical systems,especially as the industry transitions toward more autonomous vessels. 展开更多
关键词 Fault tree analysis Bayesian network RELIABILITY REDUNDANCY Internal combustion engine
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改进Deep Q Networks的交通信号均衡调度算法
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作者 贺道坤 《机械设计与制造》 北大核心 2025年第4期135-140,共6页
为进一步缓解城市道路高峰时段十字路口的交通拥堵现象,实现路口各道路车流均衡通过,基于改进Deep Q Networks提出了一种的交通信号均衡调度算法。提取十字路口与交通信号调度最相关的特征,分别建立单向十字路口交通信号模型和线性双向... 为进一步缓解城市道路高峰时段十字路口的交通拥堵现象,实现路口各道路车流均衡通过,基于改进Deep Q Networks提出了一种的交通信号均衡调度算法。提取十字路口与交通信号调度最相关的特征,分别建立单向十字路口交通信号模型和线性双向十字路口交通信号模型,并基于此构建交通信号调度优化模型;针对Deep Q Networks算法在交通信号调度问题应用中所存在的收敛性、过估计等不足,对Deep Q Networks进行竞争网络改进、双网络改进以及梯度更新策略改进,提出相适应的均衡调度算法。通过与经典Deep Q Networks仿真比对,验证论文算法对交通信号调度问题的适用性和优越性。基于城市道路数据,分别针对两种场景进行仿真计算,仿真结果表明该算法能够有效缩减十字路口车辆排队长度,均衡各路口车流通行量,缓解高峰出行方向的道路拥堵现象,有利于十字路口交通信号调度效益的提升。 展开更多
关键词 交通信号调度 十字路口 Deep Q networks 深度强化学习 智能交通
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TIME-SPACE CONCEPT FOR PRECISION MEASUREMENT 被引量:4
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作者 LIU Xiaokang PENG Donglin ZHU Ge WANG Xianquan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第3期112-115,共4页
The transformation between time and space is discussed. To improve real-time response speed of intelligent measuring system, the concept of exchanging program execution time with more circuitry is presented working in... The transformation between time and space is discussed. To improve real-time response speed of intelligent measuring system, the concept of exchanging program execution time with more circuitry is presented working in cycle mode. Displacement measuring by magnification is achieved with period measurement by magnification. To change the condition that traditional precision measurement depends on machining precision greatly, the concept of measuring space with time and theory of time-space coordinate transformation are proposed. Guided by the idea of measuring space with time, differential frequency measurement system and time grating displacement sensor are developed based on the proposed novel methods. And high-precision measurement is achieved without high-precision manufacture, which embeds the remarkable characteristics of low cost but high precision to the devices. Experiment and test results conform the validity of the proposed time-space concept. 展开更多
关键词 time-space Precision measurement Control flow Differential frequency Time grating
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Adaptive time-space resource and waveform control for collocated MIMO radar with simultaneous multi-beam 被引量:4
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作者 CHENG Ting LI Xi +1 位作者 TAN Qianqian SU Yang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第1期47-59,共13页
Collocated multiple input multiple output(MIMO)radar,which has agile multi-beam working mode,can offer enhanced multiple targets tracking(MTT)ability.In detail,it can illuminate different targets simultaneously with m... Collocated multiple input multiple output(MIMO)radar,which has agile multi-beam working mode,can offer enhanced multiple targets tracking(MTT)ability.In detail,it can illuminate different targets simultaneously with multi-beam or one wide beam among multi-beam,providing greater degree of freedom in system resource control.An adaptive time-space resource and waveform control optimization model for the collocated MIMO radar with simultaneous multi-beam is proposed in this paper.The aim of the proposed scheme is to improve the overall tracking accuracy and meanwhile minimize the resource consumption under the guarantee of effective targets detection.A resource and waveform control algorithm which integrates the genetic algorithm(GA)is proposed to solve the optimization problem.The optimal transmitting waveform parameters,system sampling period,sub-array number,binary radar tracking parameterχ_i(t_k),transmitting energy and multi-beam direction vector combination are chosen adaptively,where the first one realizes the waveform control and the latter five realize the timespace resource allocation.Simulation results demonstrate the effectiveness of the proposed control method. 展开更多
关键词 multiple targets tracking(MTT) collocated multiple input multiple output(MIMO)radar time-space resource allocation waveform control
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Adaptive resource management for multi-target tracking in co-located MIMO radar based on time-space joint allocation 被引量:2
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作者 SU Yang CHENG Ting +2 位作者 HE Zishu LI Xi LU Yanxi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第5期916-927,共12页
Compared with the traditional phased array radar, the co-located multiple-input multiple-output(MIMO) radar is able to transmit orthogonal waveforms to form different illuminating modes, providing a larger freedom deg... Compared with the traditional phased array radar, the co-located multiple-input multiple-output(MIMO) radar is able to transmit orthogonal waveforms to form different illuminating modes, providing a larger freedom degree in radar resource management. In order to implement the effective resource management for the co-located MIMO radar in multi-target tracking,this paper proposes a resource management optimization model,where the system resource consumption and the tracking accuracy requirements are considered comprehensively. An adaptive resource management algorithm for the co-located MIMO radar is obtained based on the proposed model, where the sub-array number, sampling period, transmitting energy, beam direction and working mode are adaptively controlled to realize the time-space resource joint allocation. Simulation results demonstrate the superiority of the proposed algorithm. Furthermore, the co-located MIMO radar using the proposed algorithm can satisfy the predetermined tracking accuracy requirements with less comprehensive cost compared with the phased array radar. 展开更多
关键词 co-located multiple-input multiple-output(MIMO)radar adaptive resource management multi-target tracking sub-array division time-space joint allocation
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A compass time-space model-based virtual IP routing scheme for NTSN satellite constellations 被引量:2
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作者 Yifei JIANG Shufan WU Qiankun MO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2023年第9期280-288,共9页
Recently,Non-Terrestrial Satellite Networks(NTSTs)have gained more and more attentions due to global coverage,low latency,and high-speed communications.The routing scheme is one of the primary challenges for NTSNs,due... Recently,Non-Terrestrial Satellite Networks(NTSTs)have gained more and more attentions due to global coverage,low latency,and high-speed communications.The routing scheme is one of the primary challenges for NTSNs,due to the mega scale of an NTSN constellation and the dynamic topology feature.To solve many pressing problems,a Compass time-space Model-based Virtual IP(CMVIP)routing scheme is proposed in this paper.In order to compensate for discontinuities in existing topology models,a compass-shaped time-space model is proposed.It can be adapted with Inter-Satellite-Link(ISL)and Ground-Satellite-Link(GSL)transmissions.A distributed algorithm with multiple optimization objectives and multiple constraints is applied for routing path discovery.To more realistically verify the specific scheme,a traffic model that supports two different services is proposed.Access and bearer services are the two main applications of an NTSN.Experimental results demonstrate that the proposed scheme achieves superior Qualityof-Service(QoS)performance.In addition,comparison results demonstrate that the CMVIP routing scheme is superior to the Virtual-Topology-based Shortest Path(VT-SP)routing algorithm. 展开更多
关键词 Quality of service Routing scheme Satellite communication Satellite constellation Satellite network
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LATITUDES Network:提升证据合成稳健性的效度(偏倚风险)评价工具库
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作者 廖明雨 熊益权 +7 位作者 赵芃 郭金 陈靖文 刘春容 贾玉龙 任燕 孙鑫 谭婧 《中国循证医学杂志》 北大核心 2025年第5期614-620,共7页
证据合成是对现有研究证据进行系统收集、分析和整合的过程,其结果依赖于纳入原始研究的质量,而效度评价(validity assessment,又称偏倚风险评价)则是评估这些原始研究质量的重要手段。现有效度评价工具种类繁多,但部分工具缺乏严格的... 证据合成是对现有研究证据进行系统收集、分析和整合的过程,其结果依赖于纳入原始研究的质量,而效度评价(validity assessment,又称偏倚风险评价)则是评估这些原始研究质量的重要手段。现有效度评价工具种类繁多,但部分工具缺乏严格的开发过程和评估,证据合成过程中应用不恰当的效度评价工具开展文献质量评价,可能会影响研究结论的准确性,误导临床实践。为解决这一困境,2023年9月英国Bristol大学学者牵头成立了效度评价工具一站式资源站LATITUDES Network。该网站致力于收集、整理和推广研究效度评价工具,以促进原始研究效度评价的准确性,提升证据合成的稳健性和可靠性。本文对LATITUDES Network成立背景、收录的效度评价工具,以及评价工具使用的培训资源等内容进行了详细介绍,以期为国内学者更多地了解LATITUDES Network,更好地运用恰当的效度评价工具开展文献质量评价,以及为开发效度评价工具等提供参考。 展开更多
关键词 效度评价 偏倚风险 证据合成 LATITUDES network
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Application of virtual reality technology improves the functionality of brain networks in individuals experiencing pain 被引量:3
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作者 Takahiko Nagamine 《World Journal of Clinical Cases》 SCIE 2025年第3期66-68,共3页
Medical procedures are inherently invasive and carry the risk of inducing pain to the mind and body.Recently,efforts have been made to alleviate the discomfort associated with invasive medical procedures through the u... Medical procedures are inherently invasive and carry the risk of inducing pain to the mind and body.Recently,efforts have been made to alleviate the discomfort associated with invasive medical procedures through the use of virtual reality(VR)technology.VR has been demonstrated to be an effective treatment for pain associated with medical procedures,as well as for chronic pain conditions for which no effective treatment has been established.The precise mechanism by which the diversion from reality facilitated by VR contributes to the diminution of pain and anxiety has yet to be elucidated.However,the provision of positive images through VR-based visual stimulation may enhance the functionality of brain networks.The salience network is diminished,while the default mode network is enhanced.Additionally,the medial prefrontal cortex may establish a stronger connection with the default mode network,which could result in a reduction of pain and anxiety.Further research into the potential of VR technology to alleviate pain could lead to a reduction in the number of individuals who overdose on painkillers and contribute to positive change in the medical field. 展开更多
关键词 Virtual reality PAIN ANXIETY Salience network Default mode network
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Nonlinear Waves on Localized and Periodic Backgrounds with Time-Space Modulation
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作者 刘美坤 杨战营 杨文力 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第5期520-526,共7页
We present one family of general analytical solutions for the generalized nonlinear Schr?dinger equation with time-space modulation via the method of a combination of the Darboux transformation and similarity transfor... We present one family of general analytical solutions for the generalized nonlinear Schr?dinger equation with time-space modulation via the method of a combination of the Darboux transformation and similarity transformation. Nonlinear waves on different localized and periodic backgrounds depending on the corresponding nonlinearity modulations are obtained. In particular, we demonstrate the existence and property of localized modes on a doubleperiodic background under a special designed optical lattice potential. Our results may raise the possibility of related experiments and potential applications in nonlinear optics and Bose–Einstein condensates. 展开更多
关键词 rogue waves BREATHERS localized and periodic background time-space modulation
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A Time-Space Optimal Parallel Sorting on a Hypercube
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作者 QI JIANXIAN (Beijing Institute of System Engineering P. O.Box 9702-19, Beijing, People ’s Repuslic of China) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第Z1期465-469,共5页
In this paper we discuss a parallel sorting algorithm on a hypercube. Its time complexity is O(n logn/p) +O(n). Here, P is the number of processors available and n, the amount of items to be sorted. Take the problem o... In this paper we discuss a parallel sorting algorithm on a hypercube. Its time complexity is O(n logn/p) +O(n). Here, P is the number of processors available and n, the amount of items to be sorted. Take the problem of time-space optimization into consideration, when P≤ O(log n), this algorithm is both timespace optimal and cost optimization. But this means only speedup is O(P) and it is not linear speedup. Therefore, we further discuss relevant parallel efficiency problems. 展开更多
关键词 HYPERCUBE Parallel Sorting time-space Optimal EFFICIENCY COST Operations.
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Analytical Solutions, Moments, and Their Asymptotic Behaviors for the Time-Space Fractional Cable Equation
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作者 李灿 邓伟华 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第7期54-60,共7页
Following the fractional cable equation established in the letter [B.I. Henry, T.A.M. Langlands, and S.L.Wearne, Phys. Rev. Lett. 100(2008) 128103], we present the time-space fractional cable equation which describes ... Following the fractional cable equation established in the letter [B.I. Henry, T.A.M. Langlands, and S.L.Wearne, Phys. Rev. Lett. 100(2008) 128103], we present the time-space fractional cable equation which describes the anomalous transport of electrodiffusion in nerve cells. The derivation is based on the generalized fractional Ohm's law;and the temporal memory effects and spatial-nonlocality are involved in the time-space fractional model. With the help of integral transform method we derive the analytical solutions expressed by the Green's function; the corresponding fractional moments are calculated; and their asymptotic behaviors are discussed. In addition, the explicit solutions of the considered model with two different external current injections are also presented. 展开更多
关键词 anomalous diffusion time-space FRACTIONAL CABLE EQUATION Green’s FUNCTION Fox-H FUNCTION
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A "TIME-SPACE" RELATED DESIGN METHOD OF FREEZING WALL
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作者 陈湘生 《Journal of Coal Science & Engineering(China)》 1996年第2期63-66,共4页
Artificially ground freezing (AGF) is one of the main methods to establish temporary support for shaft sinking in unstable water bearing strata. Domde (1915) formula based on frozen soil strength has widely been used ... Artificially ground freezing (AGF) is one of the main methods to establish temporary support for shaft sinking in unstable water bearing strata. Domde (1915) formula based on frozen soil strength has widely been used for designing freezing wall thickness. However, it can not ensure the stability of freezing wall, nor guarantee the safety of shaft construction as frozen depth increases in unstable water bearing strata. F A. Auld (1985, 1988)[1,2] presented a design method of freezing wall, which is on the basis of strength and stability, together with deformation of freezing wall. This paper, according to the practice in China, describes a "time -space" related design method for deep freezing wall. The method is based on "time-space" concept, which includes influence of excavation rate of advance, unsupported length of freezing wall and the sump state on inward deformation of freezing wall, and the allowable pipe deformation caused by inward deformation of freezing wall. Finally, successful application of this method to the large scale coal mine-Jining No. 2 Mine[3] in Shandong Province of China is presented. It saved much investment compared with F. A. Auld’s design for the same mine. 展开更多
关键词 ground freezing freezing wall DESIGN time-space concept
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