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Orthogonal Frequency Division Multiplexing Adaptive Technology for Multinode Users of Seawater Channel Based on Inductively Coupled Mooring Chain
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作者 ZHENG Yu LIU Yingjie +3 位作者 REN Yuanhong FEI Chen ZHANG Shijiang LI Hongzhi 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第5期1243-1252,共10页
As an important part of buoy-type ocean monitoring systems,the inductively coupled mooring chain solves the problem of data cotransmission through the multinode sensors that it carries,which is significant for the rap... As an important part of buoy-type ocean monitoring systems,the inductively coupled mooring chain solves the problem of data cotransmission through the multinode sensors that it carries,which is significant for the rapid acquisition of fish,hydrology,and other information.This paper is based on a seawater channel transmission model with a depth of 300 m and a bandwidth of 2 MHz.An orthogonal frequency division multiplexing(OFDM)technology is used to overcome the multipath effect of signal transmission on a seawater medium.The adaptive technology is integrated into the OFDM,and an improved joint subcarrier and bit power allocation algorithm is proposed.This algorithm solves the problem of dynamic subcarrier allocation during the cotransmission of underwater multinode user data in seawater channels.The results show that the algorithm complexity can be reduced by 0.18126×10^(-2)s during one complete OFDM system data transmission by the improved greedy algorithm,and a total of 216 bits are transmitted by the OFDM.The normalized channel capacity can be improved by 0.012 bit s^(-1)Hz^(-1).At the bit error ratio(BER)of 10^(-3),the BER performance can be improved by approximately 6 d B.When the numbers of users are 4 and 8,the improved algorithm increases the channel capacity,and the higher the number of users,the more evident the channel capacity improvement effect is.The results of this paper have an important reference value for enhancing the transmission performance of inductively coupled mooring chain underwater multinode data. 展开更多
关键词 inductively coupled mooring chain seawater channel multinode users OFDM adaptive technology
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Adaptive Route Sink Relocation Using Cluster Head Chain Cycling Model in WSN
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作者 M.Sudha P.Shanmugapriya +1 位作者 Rami Q.Malik Ahmed Alkhayyat 《Intelligent Automation & Soft Computing》 SCIE 2023年第5期1811-1826,共16页
Wireless Sensor Networks(WSN)have revolutionized the processes involved in industrial communication.However,the most important challenge faced by WSN sensors is the presence of limited energy.Multiple research inves-t... Wireless Sensor Networks(WSN)have revolutionized the processes involved in industrial communication.However,the most important challenge faced by WSN sensors is the presence of limited energy.Multiple research inves-tigations have been conducted so far on how to prolong the energy in WSN.This phenomenon is a result of inability of the network to have battery powered-sensor terminal.Energy-efficient routing on packetflow is a parallel phenomenon to delay nature,whereas the primary energy gets wasted as a result of WSN holes.Energy holes are present in the vicinity of sink and it is an important efficient-routing protocol for WSNs.In order to solve the issues discussed above,an energy-efficient routing protocol is proposed in this study named as Adaptive Route Decision Sink Relocation Protocol using Cluster Head Chain Cycling approach(ARDSR-CHC2H).The proposed method aims at improved communica-tion at sink-inviting routes.At this point,Cluster Head Node(CHN)is selected,since it consumes low energy and permits one node to communicate with others in two groups.The main purpose of the proposed model is to reduce energy con-sumption and define new interchange technology.A comparison of simulation results demonstrates that the proposed algorithm achieved low cluster creation time,better network error and high Packet Delivery Rate with less network failure. 展开更多
关键词 Cluster head energy-efficient routing chain routing cycling approach sink relocation adaptive routing WSN
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Adaptive proportional integral differential control based on radial basis function neural network identification of a two-degree-of-freedom closed-chain robot
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作者 陈正洪 王勇 李艳 《Journal of Shanghai University(English Edition)》 CAS 2008年第5期457-461,共5页
A closed-chain robot has several advantages over an open-chain robot, such as high mechanical rigidity, high payload, high precision. Accurate trajectory control of a robot is essential in practical-use. This paper pr... A closed-chain robot has several advantages over an open-chain robot, such as high mechanical rigidity, high payload, high precision. Accurate trajectory control of a robot is essential in practical-use. This paper presents an adaptive proportional integral differential (PID) control algorithm based on radial basis function (RBF) neural network for trajectory tracking of a two-degree-of-freedom (2-DOF) closed-chain robot. In this scheme, an RBF neural network is used to approximate the unknown nonlinear dynamics of the robot, at the same time, the PID parameters can be adjusted online and the high precision can be obtained. Simulation results show that the control algorithm accurately tracks a 2-DOF closed-chain robot trajectories. The results also indicate that the system robustness and tracking performance are superior to the classic PID method. 展开更多
关键词 closed-chain robot radial basis function (RBF) neural network adaptive proportional integral differential (PID) control identification neural network
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An adaptive genetic algorithm with diversity-guided mutation and its global convergence property 被引量:9
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作者 李枚毅 蔡自兴 孙国荣 《Journal of Central South University of Technology》 EI 2004年第3期323-327,共5页
An adaptive genetic algorithm with diversity-guided mutation, which combines adaptive probabilities of crossover and mutation was proposed. By means of homogeneous finite Markov chains, it is proved that adaptive gene... An adaptive genetic algorithm with diversity-guided mutation, which combines adaptive probabilities of crossover and mutation was proposed. By means of homogeneous finite Markov chains, it is proved that adaptive genetic algorithm with diversity-guided mutation and genetic algorithm with diversity-guided mutation converge to the global optimum if they maintain the best solutions, and the convergence of adaptive genetic algorithms with adaptive probabilities of crossover and mutation was studied. The performances of the above algorithms in optimizing several unimodal and multimodal functions were compared. The results show that for multimodal functions the average convergence generation of the adaptive genetic algorithm with diversity-guided mutation is about 900 less than that of (adaptive) genetic algorithm with adaptive probabilities and genetic algorithm with diversity-guided mutation, and the adaptive genetic algorithm with diversity-guided mutation does not lead to premature convergence. It is also shown that the better balance between overcoming premature convergence and quickening convergence speed can be gotten. 展开更多
关键词 diversity-guided mutation adaptive genetic algorithm Markov chain global convergence
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An Improved Cooperative Adaptive Cruise Control(CACC) Algorithm Considering Invalid Communication 被引量:3
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作者 WANG Pangwei WANG Yunpeng +1 位作者 YU Guizhen TANG Tieqiao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第3期468-474,共7页
For the Cooperative Adaptive Cruise Control (CACC) Algorithm, existing research studies mainly focus on how inter-vehicle communication can be used to develop CACC controller, the influence of the communication dela... For the Cooperative Adaptive Cruise Control (CACC) Algorithm, existing research studies mainly focus on how inter-vehicle communication can be used to develop CACC controller, the influence of the communication delays and lags of the actuators to the string stability. However, whether the string stability can be guaranteed when inter-vehicle communication is invalid partially has hardly been considered. This paper presents an improved CACC algorithm based on the sliding mode control theory and analyses the range of CACC controller parameters to maintain string stability. A dynamic model of vehicle spacing deviation in a platoon is then established, and the string stability conditions under improved CACC are analyzed. Unlike the traditional CACC algorithms, the proposed algorithm can ensure the functionality of the CACC system even if inter-vehicle communication is partially invalid. Finally, this paper establishes a platoon of five vehicles to simulate the improved CACC algorithm in MATLAB/Simulink, and the simulation results demonstrate that the improved CACC algorithm can maintain the string stability of a CACC platoon through adjusting the controller parameters and enlarging the spacing to prevent accidents. With guaranteed string stability, the proposed CACC algorithm can prevent oscillation of vehicle spacing and reduce chain collision accidents under real-world circumstances. This research proposes an improved CACC algorithm, which can guarantee the string stability when inter-vehicle communication is invalid. 展开更多
关键词 Cooperative adaptive cruise control (CACC) sliding mode control chain collision accidents vehicular ad hoc networks (VANETs)
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Adaptive designs for sequential experiments 被引量:3
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作者 林正炎 张立新 《Journal of Zhejiang University Science》 EI CSCD 2003年第2期214-220,共7页
Various adaptive designs have been proposed and applied to clinical trials, bio assay, psychophysics, etc.Adaptive designs are also useful in high cost engineering trials.More and more people have been paying attentio... Various adaptive designs have been proposed and applied to clinical trials, bio assay, psychophysics, etc.Adaptive designs are also useful in high cost engineering trials.More and more people have been paying attention to these design methods. This paper introduces several broad families of designs, such as the play-the-winner rule, randomized play-the-winner rule and its generalization to the multi-arm case, doubly biased coin adaptive design, Markov chain model. 展开更多
关键词 Clinical trial adaptive designs (Randomized) Play-the-winner rule Biased coin design Markov chain Asymptotic properties Urn model.
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Active Kriging-Based Adaptive Importance Sampling for Reliability and Sensitivity Analyses of Stator Blade Regulator 被引量:2
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作者 Hong Zhang Lukai Song Guangchen Bai 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第3期1871-1897,共27页
The reliability and sensitivity analyses of stator blade regulator usually involve complex characteristics like highnonlinearity,multi-failure regions,and small failure probability,which brings in unacceptable computi... The reliability and sensitivity analyses of stator blade regulator usually involve complex characteristics like highnonlinearity,multi-failure regions,and small failure probability,which brings in unacceptable computing efficiency and accuracy of the current analysismethods.In this case,by fitting the implicit limit state function(LSF)with active Kriging(AK)model and reducing candidate sample poolwith adaptive importance sampling(AIS),a novel AK-AIS method is proposed.Herein,theAKmodel andMarkov chainMonte Carlo(MCMC)are first established to identify the most probable failure region(s)(MPFRs),and the adaptive kernel density estimation(AKDE)importance sampling function is constructed to select the candidate samples.With the best samples sequentially attained in the reduced candidate samples and employed to update the Kriging-fitted LSF,the failure probability and sensitivity indices are acquired at a lower cost.The proposed method is verified by twomulti-failure numerical examples,and then applied to the reliability and sensitivity analyses of a typical stator blade regulator.Withmethods comparison,the proposed AK-AIS is proven to hold the computing advantages on accuracy and efficiency in complex reliability and sensitivity analysis problems. 展开更多
关键词 Markov chain Monte Carlo active Kriging adaptive kernel density estimation importance sampling
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Supply Chain Finance Credit Risk Evaluation Method Based on Self-Adaption Weight 被引量:4
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作者 Yueliang Su Nan Lu 《Journal of Computer and Communications》 2015年第7期13-21,共9页
Credit risk is the core issue of supply chain finance. In the supply chain, problems happened in different enterprises can influent the whole to different degrees through transferring, thus statuses of all enterprises... Credit risk is the core issue of supply chain finance. In the supply chain, problems happened in different enterprises can influent the whole to different degrees through transferring, thus statuses of all enterprises and their different influences should be considered when evaluating the supply chain’s credit risk. We examine the characters of supply chain network and complex network, use the local growing complex network to simulate the real supply chain, use cluster analysis to classify the company into several levels;Introducing each level’s self-adaption weight formula according to the company’s quantity and degrees of this level and use the weight to improve the credit evaluation method. The research results indicate that complex network can be used to simulate the supply chain. The credit risk evaluation (CRE) of an enterprise level with bigger note degrees has a greater weight in the supply chain system’s CRE, thus has greater effect on the whole chain. Considering different influences of different enterprise levels can improve credit risk evaluation method’s sensitivity. 展开更多
关键词 Supply chain FINANCE CREDIT RISK Self-adaption WEIGHT Complex Network
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Innovation in two contrasting value chains:Constraints and opportunities for adopting alternative crop production in the Vietnamese Mekong River Delta
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作者 Sang Thanh LE Nhu Huynh MAO +1 位作者 Paul KRISTIANSEN Michael COLEMAN 《Regional Sustainability》 2025年第1期75-89,共15页
Agricultural production(especially intensive rice production)is a primary income source for over 2.0×10^(7) people in the Vietnamese Mekong River Delta.However,adverse climate change impacts,socio-economic change... Agricultural production(especially intensive rice production)is a primary income source for over 2.0×10^(7) people in the Vietnamese Mekong River Delta.However,adverse climate change impacts,socio-economic change,and high dependence on farm inputs for intensive production constrain the longer-term sustainability of rice systems.Government and agribusiness actors are encouraging more farmers to grow non-rice crops and supporting the upscaling of alternative crops to paddy rice.We used a qualitative approach to investigate the value chain characteristics,as well as constraints and opportunities of alternative crops via two case studies(baby corn and honeydew melon)in An Giang and Hau Giang provinces,Vietnam.Data collection involved focus group discussions with local farmers and interviews with farmers and industry experts.Thematic analysis was used to compile the findings,and the results were validated with local government staff.The baby corn value chain featured on-going and stable market demand(including value-addition)and better vertical coordination(e.g.,written contracts and financial support).The honeydew melon value chain featured positive relationships between farmers and traders despite less-developed vertical coordination.There are opportunities for value chain engagement through product quality certification,value-addition,and accessing high-value domestic and export markets.However,farmers require crop-specific and generic support from private and public sectors.Increased labour requirements and limited access to finance and credit limit value chain participation.Upscaling and marketing alternative crops can enhance farmer profitability and support non-farming agricultural business establishment,economic growth,and community development.Efficient value chains will be critical to ensure the adoption of alternative crops and development of crop-specific agribusiness models.These findings can inform policy-makers and change facilitators in designing targeted interventions to support the adoption of alternative crops in the study area as well as in Vietnam and globally. 展开更多
关键词 Value chain Transformative adaptation Alternative crop Honeydew melon Baby corn Vietnamese Mekong River Delta
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Model-driven full system dynamics estimation of PMSM-driven chain shell magazine 被引量:2
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作者 Kai Wei Longmiao Chen Quan Zou 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第9期147-156,共10页
Based on the system dynamic model, a full system dynamics estimation method is proposed for a chain shell magazine driven by a permanent magnet synchronous motor(PMSM). An adaptive extended state observer(AESO) is pro... Based on the system dynamic model, a full system dynamics estimation method is proposed for a chain shell magazine driven by a permanent magnet synchronous motor(PMSM). An adaptive extended state observer(AESO) is proposed to estimate the unmeasured states and disturbance, in which the model parameters are adjusted in real time. Theoretical analysis shows that the estimation errors of the disturbances and unmeasured states converge exponentially to zero, and the parameter estimation error can be obtained from the extended state. Then, based on the extended state of the AESO, a novel parameter estimation law is designed. Due to the convergence of AESO, the novel parameter estimation law is insensitive to controllers and excitation signal. Under persistent excitation(PE) condition, the estimated parameters will converge to a compact set around the actual parameter value. Without PE signal, the estimated parameters will converge to zero for the extended state. Simulation and experimental results show that the proposed method can accurately estimate the unmeasured states and disturbance of the chain shell magazine, and the estimated parameters will converge to the actual value without strictly continuous PE signals. 展开更多
关键词 chain shell magazine Full system dynamics estimation Disturbance estimation Parameter estimation adaptive extended state observer
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Integrating value-chain approach with participatory multicriteria analysis for sustainable planning of a niche crop in Indian Himalayas
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作者 Sudeshna Maya SEN Arun KANSAL 《Journal of Mountain Science》 SCIE CSCD 2019年第10期2417-2434,共18页
The value-chain approach(VCA)was used for exploring how a niche crop,namely large cardamom(Amomum subulatum Roxb.),can be developed sustainably to increase incomes and enhance rural livelihoods in the mountains.Large ... The value-chain approach(VCA)was used for exploring how a niche crop,namely large cardamom(Amomum subulatum Roxb.),can be developed sustainably to increase incomes and enhance rural livelihoods in the mountains.Large cardamom is a high-value,agro-climatically suitable,and non-perishable spice crop grown in the Himalayan region.Originating in Sikkim,the crop is important to the local economy and is sold in both domestic and international markets;however,its production in India has been declining significantly in recent years.Using VCA and participatory methods of data collection the study helped elicit value chain actors’perspectives on various reasons for the decline as well as potential strategies to improve the cardamom value chain.The results present the multiple environmental and climatic(e.g.water stress),social(e.g.women participation)and institutional(e.g.lack of trust between actors)challenges and corresponding upgrading strategies.Through participatory multi-criteria analysis(MCA),the strategies were prioritized based on the overall preferences of multiple stakeholders.The analysis considered eight criteria and 25 options,or strategies,and found that that marketability and profitability were the most important criteria,and increasing cardamom production,the most important optiontrait.Stakeholder discussions along with sensitivity analysis also showed how these options could be implemented and revealed how criteria preferences can change with expert inputs.This combination of VCA and MCA,because it supports participatory decision-making and balances multiple dimensions of sustainable development,can be effectively deployed in planning for agricultural development in the mountains. 展开更多
关键词 Large CARDAMOM PARTICIPATORY decision-making UPGRADING strategies Climate change adaptation SIKKIM Sustainable Value chain
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Japanese Media Strategy: The Recognition of Economic Value Chains
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作者 Seiko Yasumoto 《Journalism and Mass Communication》 2012年第10期998-1011,共14页
This paper examines, as a case study, Japanese media production, remaking, and transferences of media content derived from the manga Janguru Taitei (Jungle Emperor) and contemporary Japanese government strategies to... This paper examines, as a case study, Japanese media production, remaking, and transferences of media content derived from the manga Janguru Taitei (Jungle Emperor) and contemporary Japanese government strategies to protect and promote Japanese cultural and economic value within the content business. The study utilizes methodological triangulation inclusive of textual, document, and value chain analysis. The Japanese government has progressively appreciated the intrinsic value of the media content from both a commercial and cultural context and the loss of value in unregulated segments of the regional market. In 2003, they established an Intellectual Property Strategy Group to support and promote the Japanese media content business. There has been a continuum of policy development since then to protect and amplify the financial value of Japanese media products. All of the developments in media industry are fuelled not only by government regulations, the imagination of talented artists and writers, and the growing regionalization and internationalization of the industry but also the "bottom line" emerging from the value chain. The recognition of the need for sustaining profit growth to continue the viability of original and remade content in Japan is paramount for Japan. 展开更多
关键词 Japanese media strategy economic value chains adaptATION
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气候适应型城市建设、企业韧性与供应链溢出 被引量:1
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作者 刘嫦 夏琴 孙洪锋 《技术经济与管理研究》 北大核心 2025年第8期31-39,共9页
以政策工具赋能企业韧性培育,是筑牢供应链安全屏障的关键路径。以气候适应型城市建设作为准自然实验,研究气候适应政策对企业韧性的影响及其供应链溢出效应。研究发现:气候适应型城市建设通过优化城市气候适应基础设施、提高企业气候... 以政策工具赋能企业韧性培育,是筑牢供应链安全屏障的关键路径。以气候适应型城市建设作为准自然实验,研究气候适应政策对企业韧性的影响及其供应链溢出效应。研究发现:气候适应型城市建设通过优化城市气候适应基础设施、提高企业气候风险感知能力和推动企业绿色转型等渠道显著提升企业韧性。异质性分析呈现“风险匹配”与“能力适配”特征,即高物理气候风险暴露区、强环境规制区及脆弱性企业群体的政策响应更显著。进一步分析发现,气候适应政策存在显著后向溢出效应,其通过运营协同强化与绿色技术扩散双通道,驱动上游企业韧性增强。研究表明,激活气候适应政策的韧性催化效能,对推动气候适应型绿色化协同转型、提升产业链供应链韧性和促进经济高质量发展具有重要意义。 展开更多
关键词 气候适应型城市建设 企业韧性 供应链溢出 供应链韧性 城市韧性
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“人才-科技-产业”三链协同下中国新质生产力发展路径研究——基于动态QCA方法的实证检验 被引量:1
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作者 李亚玲 饶静 《工业技术经济》 北大核心 2025年第5期33-42,共10页
本文基于“人才-科技-产业”三链协同理论框架,以2014~2023年我国30个省(区、市)为样本,运用动态QCA方法深入探究“人才-科技-产业”复杂生态系统下各省(区、市)发展新质生产力的最优适配路径。研究发现,新质生产力发展存在5条有效组态... 本文基于“人才-科技-产业”三链协同理论框架,以2014~2023年我国30个省(区、市)为样本,运用动态QCA方法深入探究“人才-科技-产业”复杂生态系统下各省(区、市)发展新质生产力的最优适配路径。研究发现,新质生产力发展存在5条有效组态路径,在不同地区与不同时期各显成效;产业基础、科技产出、科技投入、人才储备、人才培育、“三链”协同为新质生产力发展的6个关键核心条件,其中“三链”协同是唯一一个在5条高组态路径中均未缺失的条件,表现出其对新质生产力发展的核心支撑作用。本文为剖析新质生产力的驱动因素及其在不同地区、不同时期的实践路径提供了理论依据和实证支持,为制定因地制宜、因时制宜发展新质生产力的政策提供了有益建议。 展开更多
关键词 “人才-科技-产业”三链协同 新质生产力 因地制宜 因时制宜 动态QCA方法 多元组态路径 复杂生态系统 区域经济
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统筹区域与城市的“精准适配”安全韧性规划方法探索
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作者 王凯 徐辉 +5 位作者 贾鹏飞 付凯 李长风 周亚杰 陈志芬 高均海 《中国工程科学》 北大核心 2025年第4期43-54,共12页
安全韧性是城市建设的基本前提,构建多尺度联动的安全韧性规划方法对于提升城市整体韧性能力、促进城市高质量发展具有重要的科学意义。本研究立足国家和区域视角,针对城镇空间发展与安全风险之间的适配机理这一科学问题,解析不同空间... 安全韧性是城市建设的基本前提,构建多尺度联动的安全韧性规划方法对于提升城市整体韧性能力、促进城市高质量发展具有重要的科学意义。本研究立足国家和区域视角,针对城镇空间发展与安全风险之间的适配机理这一科学问题,解析不同空间层次的安全风险特征,构建统筹区域与城市的安全韧性规划框架及“精准适配”的安全韧性规划技术体系,形成对安全韧性本底的精准分析、因地制宜的韧性规划生成、智慧响应的动态评估等三大关键技术;建立了5类一级、18类二级的全国安全韧性建设模式分区,以及不同地区差异化的“密度-规模”双控指标体系及关键阈值。该方法在京津冀地区、甘肃舟曲特大泥石流灾后重建等规划实践中实现了工程化应用,为从源头推进城市建设的安全风险预控,整体提升城市韧性能力提供了科学的解决方案。 展开更多
关键词 精准适配 灾害链 安全韧性要素 韧性空间 多尺度联动
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从脆弱性到适应性:气候风险对供应链韧性的影响研究
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作者 余怒涛 成杭 +1 位作者 阮萍 王蓬 《证券市场导报》 北大核心 2025年第10期30-42,54,共14页
全球气候风险已对企业供应链产生明显冲击,如何缓解气候风险对供应链韧性的不利影响成为亟待解决的问题。本文以沪深A股上市公司为样本,运用文本分析法和机器学习技术构建气候风险指标,探究气候风险对供应链韧性的影响。研究发现,气候... 全球气候风险已对企业供应链产生明显冲击,如何缓解气候风险对供应链韧性的不利影响成为亟待解决的问题。本文以沪深A股上市公司为样本,运用文本分析法和机器学习技术构建气候风险指标,探究气候风险对供应链韧性的影响。研究发现,气候风险降低了供应链匹配效率,抬高了企业的生产成本,从而降低了供应链韧性。异质性分析表明,针对位于产业链上游、绿色发展水平较低、管理者能力较低的企业,气候风险对供应链韧性的负向影响更显著。进一步分析发现,从企业内部管理的角度,提升数字技术创新水平、提高资源调整灵活性、提升ESG表现等,从外部监督的角度,营造正面的媒体环境形成“示范效应”、出台气候适应型城市建设试点政策等,均能有效缓解气候风险对供应链韧性的负向影响。本文从气候风险出发,为理解供应链韧性提供了新的视角,也为企业构建气候适应性供应链提供了启示。 展开更多
关键词 气候风险 供应链韧性 气候适应性
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供应链数字化促进企业高质量发展了吗?——基于企业动态能力视角的分析 被引量:1
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作者 黄静 阎洪睿 +1 位作者 向旺 郑婷 《珞珈管理评论》 2025年第5期1-28,共28页
供应链数字化的发展推动了链上企业的协同联动与价值延伸,逐渐成为企业转变生产方式和提升生产效率的重要动力。为探究供应链数字化是否真正促进了企业高质量发展,本文基于企业动态能力视角,选取2013—2022年中国沪深A股上市企业数据,... 供应链数字化的发展推动了链上企业的协同联动与价值延伸,逐渐成为企业转变生产方式和提升生产效率的重要动力。为探究供应链数字化是否真正促进了企业高质量发展,本文基于企业动态能力视角,选取2013—2022年中国沪深A股上市企业数据,采用双重差分法(DID)实证检验供应链数字化对企业高质量发展的影响及其异质性机制。研究发现:(1)供应链数字化能够显著促进企业高质量发展,且这一结论在多种稳健性检验下依然成立;(2)供应链数字化对企业高质量发展的促进作用在东部地区企业、高产业集聚水平地区企业和资本密集型企业中更显著;(3)企业适应能力、吸收能力和创新能力是供应链数字化驱动企业高质量发展的潜在机制,但在这一过程中企业普遍存在“短期主义”现象。具体表现为,企业更倾向于维护上游供应商关系网络,表现出对创新投入和技术吸收的阻碍,同时加强渐进性创新活动。本研究揭示了中国情境下,受“短期主义”影响的供应链数字化驱动企业高质量发展的内在机理,并为企业在动态环境中通过供应链数字化获取竞争优势、实现高质量发展提供了理论依据和决策参考。 展开更多
关键词 供应链数字化 企业高质量发展 动态能力 适应能力 吸收能力 创新能力
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双馈风机宽频受迫扭振抑制的模型参考自适应控制方法
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作者 王晓兰 李朝辉 《重庆大学学报》 北大核心 2025年第9期37-49,共13页
湍流风激励场景下双馈风力发电系统轴系传动链在低频段存在宽频受迫扭振问题,影响机组稳定运行。提出了扭振抑制的模型参考自适应控制(model reference adaptive control,MRAC)方法,建立了考虑最优转矩控制和带通滤波器参数的轴系宽频... 湍流风激励场景下双馈风力发电系统轴系传动链在低频段存在宽频受迫扭振问题,影响机组稳定运行。提出了扭振抑制的模型参考自适应控制(model reference adaptive control,MRAC)方法,建立了考虑最优转矩控制和带通滤波器参数的轴系宽频受迫扭振模型,利用系统输入量和输出量设计前馈控制器和自适应控制律,避免了传动链状态变量不易测量的难题,使向双馈风力发电系统传动链提供主动阻尼的带通滤波器主要参数进行自适应调节,最终传动链动态响应跟踪稳定的参考模型。以1.5 MW双馈风力发电系统为例,在持续性湍流风激励场景下,仿真验证MRAC的跟踪效果,对比电气阻尼重塑方法和MRAC方法对宽频受迫扭振的抑制性能。结果表明,所提出的MRAC方法能够使被控对象稳定跟踪参考模型,跟踪平均误差不超过4.94%;相比于电气阻尼重塑方法,采取MRAC对双馈风力发电系统传动链宽频受迫扭振抑制效果提升了21.77%,柔性传动轴扭矩和发电机输出有功功率波动均减小。 展开更多
关键词 双馈风力发电系统 轴系传动链 宽频受迫扭振 模型参考自适应控制 扭振抑制
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基于作战资源管控的自适应杀伤网构建方法 被引量:1
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作者 丁海斌 周霞 蔡刚 《指挥信息系统与技术》 2025年第2期20-26,共7页
总结分析了美军从杀伤链到杀伤网的发展历程,研究了作战资源的统一管理和敏捷构造关键技术,提出了一种基于作战资源管控的自适应杀伤网构建方法。探索研制了“即插即用”的作战资源统一管控、任务编排、任务派单和基于群组协同的模块原... 总结分析了美军从杀伤链到杀伤网的发展历程,研究了作战资源的统一管理和敏捷构造关键技术,提出了一种基于作战资源管控的自适应杀伤网构建方法。探索研制了“即插即用”的作战资源统一管控、任务编排、任务派单和基于群组协同的模块原型,初步构建了基于作战资源管控的自适应杀伤网,并在相关系统中进行了应用。实践证明,敏捷杀伤网的响应时间与体系对抗能力可得到有效提升。 展开更多
关键词 杀伤链 杀伤网 自适应 作战资源管控
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Strong Approximations of Martingale Vectors and Their Applications in Markov-Chain Adaptive Designs 被引量:3
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作者 Li-xinZhang 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2004年第2期337-352,共16页
The strong approximations of a class of R^d-valued martingales are considered.The conditions usedin this paper are easier to check than those used in [3] and [9].As an application,the strong approximation ofa class of... The strong approximations of a class of R^d-valued martingales are considered.The conditions usedin this paper are easier to check than those used in [3] and [9].As an application,the strong approximation ofa class of non-homogenous Markov chains is established,and the asymptotic properties are established for themulti-treatment Markov chain adaptive designs in clinical trials. 展开更多
关键词 MARTINGALE Non-homogenous Markov chain Wiener processes strong approximation adaptive designs asymptotic properties
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