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Study on the Characteristics of A New Hybrid Mooring System for DualPlatform Joint Operations 被引量:1
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作者 SHEN Zhong-xiang YUAN Zhao-jun +1 位作者 LI Hong-bin ZHU Chen-yang 《China Ocean Engineering》 SCIE EI CSCD 2023年第3期506-518,共13页
As the sustainable exploitation of marine resources develops,dual-platform joint operation has caught increasing attention.Dual-platform joint operation requires smaller relative motion between the two sub-platforms,w... As the sustainable exploitation of marine resources develops,dual-platform joint operation has caught increasing attention.Dual-platform joint operation requires smaller relative motion between the two sub-platforms,which is normally difficult to be satisfied by the traditional mooring system.Therefore,a new hybrid mooring system is developed and studied in this article.To ensure safety during platform movements,both the number of anchor chains and the relative motion between the two sub-platforms are reduced in the new hybrid mooring system.By performing numerical simulations based on three-dimensional potential flow theory in AQWA and physical experiments,the performances of both the new hybrid and traditional mooring systems under two different wave conditions(i.e.,working wave and freak wave conditions) are systematically investigated.Regarding the new hybrid mooring system,the relative stability between the two sub-platforms of the new system is better,and the platforms can restore stability faster when affected by freak waves. 展开更多
关键词 dual-platform joint operation platform relative stability hybrid mooring system freak wave
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A survey on joint-operation application for unmanned swarm formations under a complex confrontation environment
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作者 ZHANG Jialong HAN Kun +2 位作者 ZHANG Pu HOU Zhongxi YE Lei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第6期1432-1446,共15页
With the rapid development of informatization,autonomy and intelligence,unmanned swarm formation intelligent operations will become the main combat mode of future wars.Typical unmanned swarm formations such as ground-... With the rapid development of informatization,autonomy and intelligence,unmanned swarm formation intelligent operations will become the main combat mode of future wars.Typical unmanned swarm formations such as ground-based directed energy weapon formations,space-based kinetic energy weapon formations,and sea-based carrier-based formations have become the trump card for winning future wars.In a complex confrontation environment,these sophisticated weapon formation systems can precisely strike mobile threat group targets,making them extreme deterrents in joint combat applications.Based on this,first,this paper provides a comprehensive summary of the outstanding advantages,strategic position and combat style of unmanned clusters in joint warfare to highlight their important position in future warfare.Second,a detailed analysis of the technological breakthroughs in four key areas,situational awareness,heterogeneous coordination,mixed combat,and intelligent assessment of typical unmanned aerial vehicle(UAV)swarms in joint warfare,is presented.An in-depth analysis of the UAV swarm communication networking operating mechanism during joint warfare is provided to lay the theoretical foundation for subsequent cooperative tracking and control.Then,an indepth analysis of the shut-in technology requirements of UAV clusters in joint warfare is provided to lay a theoretical foundation for subsequent cooperative tracking control.Finally,the technical requirements of UAV clusters in joint warfare are analysed in depth so the key technologies can form a closed-loop kill chain system and provide theoretical references for the study of intelligent command operations. 展开更多
关键词 unmanned swarm operation style weapon formation system mobile group target joint operation
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Improved particle swarm optimization algorithm for multi-reservoir system operation 被引量:2
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作者 Jun ZHANG Zhen WU +1 位作者 Chun-tian CHENG Shi-qin ZHANG 《Water Science and Engineering》 EI CAS 2011年第1期61-73,共13页
In this paper, a hybrid improved particle swarm optimization (IPSO) algorithm is proposed for the optimization of hydroelectric power scheduling in multi-reservoir systems. The conventional particle swarm optimizati... In this paper, a hybrid improved particle swarm optimization (IPSO) algorithm is proposed for the optimization of hydroelectric power scheduling in multi-reservoir systems. The conventional particle swarm optimization (PSO) algorithm is improved in two ways: (1) The linearly decreasing inertia weight coefficient (LDIWC) is replaced by a self-adaptive exponential inertia weight coefficient (SEIWC), which could make the PSO algorithm more balanceable and more effective in both global and local searches. (2) The crossover and mutation idea inspired by the genetic algorithm (GA) is imported into the particle updating method to enhance the diversity of populations. The potential ability of IPSO in nonlinear numerical function optimization was first tested with three classical benchmark functions. Then, a long-term multi-reservoir system operation model based on IPSO was designed and a case study was carried out in the Minjiang Basin in China, where there is a power system consisting of 26 hydroelectric power plants. The scheduling results of the IPSO algorithm were found to outperform PSO and to be comparable with the results of the dynamic programming successive approximation (DPSA) algorithm. 展开更多
关键词 particle swarm optimization self-adaptive exponential inertia weight coefficient multi-reservoir system operation hydroelectric power generation Minjiang Basin
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ADC-GERT network parameter estimation model for mission effectiveness of joint operation system 被引量:3
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作者 FANG Zhigeng WU Shuang +1 位作者 ZHANG Xiaoli SUN Yunke 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第6期1394-1406,共13页
Effectiveness evaluation of the joint operation system is an important basis for the demonstration and development of weapon equipment.With the consideration that existing models of system effectiveness evaluation sel... Effectiveness evaluation of the joint operation system is an important basis for the demonstration and development of weapon equipment.With the consideration that existing models of system effectiveness evaluation seldom describe the structural relationship among equipment clearly as well as reflect the dynamic,the analog-to-digital converter-graphical evaluation and review technique(ADC-GERT)network parameter estimation model is proposed based on the ADC model and the joint operation system structure.Firstly,analysis of the joint operation system structure and operation process is conducted to build the GERT network,where equipment subsystems are nodes and activities are directed arches.Then the mission effectiveness of equipment subsystems is calculated by the ADC model.The probability transfer parameters are modified by the mission effectiveness of equipment subsystems based on the Bayesian theorem,with the ADC-GERT network parameter estimation model constructed.Finally,a case study is used to validate the efficiency and dynamic of the ADC-GERT network parameter estimation model. 展开更多
关键词 joint operation system system mission effectiveness analog-to-digital converter(ADC)model graphical evaluation and review technique(GERT) parameter estimation
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Hemocoagulase Injection blood anesthesia in joint operation 被引量:1
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作者 Li Yang 《Journal of Medical Colleges of PLA(China)》 CAS 2011年第3期152-157,共6页
Objective:To investigate the role of Hemocoagulase Injection used in the joint operation and the effect on the blood coagulable function.Methods:A total of 60 patients who undergoing joint operation in our hospital we... Objective:To investigate the role of Hemocoagulase Injection used in the joint operation and the effect on the blood coagulable function.Methods:A total of 60 patients who undergoing joint operation in our hospital were randomly divided into two groups.Experiment group(Group A,n=30)was injected with 2 U Hemocoagulase Injection in 5 min before anesthesia induction.The contrast group(Group B,n=30)was treated with 0.9%normal saline in 5 min before anesthesia induction.Then common anesthesia was given to the two groups of patients.The venous blood was withdrawn for blood routine examination,thrombelastography and coagulable function at the time of pre-inducement, end of operation,and in 6 and 12 h after operation.The change of thrombelastograph and coagulable state were monitored during the whole surgery.And the volume of transfusion and hemorrhage between two groups was contrasted. Results:After the use of Hemocoagulase Injection,the operative time was shortened obviously(P<0.05).The volumes hemorrhage and transfusion was obviously smaller in Group A than in Group B(P<0.01).Hemocoagulase Injection did not influence fibrinogen and thrombelastograph of Group A(P>0.05).Conclusion:Hemocoagulase Injection can reduce the volumes of hemorrhage and transfusion and not influence the coagulable function.It is worth using in the joint operation. 展开更多
关键词 Hemocoagulase Injection ANESTHESIA joint operation
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An Ecologically Oriented Operation Strategy for a Multi-Reservoir System: A Case Study of the Middle and Lower Han River Basin, China 被引量:6
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作者 Hao Wang Xiaohui Lei +4 位作者 Denghua Yan Xu Wang Shuyue Wu Zhengjie Yin Wenhua Wan 《Engineering》 2018年第5期627-634,共8页
Constructing and operating a multi-reservoir system changes the natural flow regime of rivers, and thus imposes adverse impacts on riverine ecosystems. To balance human needs with ecosystem needs, this study proposes ... Constructing and operating a multi-reservoir system changes the natural flow regime of rivers, and thus imposes adverse impacts on riverine ecosystems. To balance human needs with ecosystem needs, this study proposes an ecologically oriented operation strategy for a multi-reservoir system that integrates environmental flow requirements into the joint operation of a multi-reservoir system in order to main- tain different ecological functions throughout the river. This strategy is a combination of a regular opti-mal operation scheme and a series of real-time ecological operation schemes. During time periods when the incompatibilities between human water needs and ecosystem needs for environmental flows are rel- atively small, the regular optimal operation scheme is implemented in order to maximize multiple human water-use benefits under the constraints of a minimum water-release policy. During time periods when reservoir-induced hydrological alteration imposes significant negative impacts on the river's key ecological functions, real-time ecological operation schemes are implemented in order to modify the out- flow from reservoirs to meet the environmental flow requirements of these functions. The practical use of this strategy is demonstrated for the simulation operation of a large-scale multi-reservoir system which located in the middle and lower Han River Basin in China. The results indicate that the real-time ecological operation schemes ensure the environmental flow requirements of the river's key ecological functions, and that adverse impacts on human water-use benefits can be compensated for by the regular optimal operation scheme. The ecologically oriented operation strategy for a multi-reservoir system that is proposed in this study enriches the theoretical application of the multi-reservoir system joint operation which considers environmental flow requirements. 展开更多
关键词 multi-reservoir system Ecologically oriented operation Environmental flow requirements Han River Basin
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Superconducting joints using reacted multifilament MgB_(2)wires:A technology toward cryogen-free MRI magnets
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作者 Dipak Patel Akiyoshi Matsumoto +8 位作者 Hiroaki Kumakura Yuka Hara Toru Hara Minoru Maeda Hao Liang Yusuke Yamauchi Seyong Choi Jung Ho Kim Md Shahriar A.Hossain 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期159-170,共12页
The development of superconducting joining technology for reacted magnesium diboride(MgB_(2))conductors remains a critical challenge for the advancement of cryogen-free MgB_(2)-based magnets for magnetic resonance ima... The development of superconducting joining technology for reacted magnesium diboride(MgB_(2))conductors remains a critical challenge for the advancement of cryogen-free MgB_(2)-based magnets for magnetic resonance imaging(MRI).Herein,the fabrication of superconducting joints using reacted carbon-doped multifilament MgB_(2)wires for MRI magnets is reported.To achieve successful superconducting joints,the powder-in-mold method was employed,which involved tuning the filament protection mechanism,the powder compaction pressure,and the heat treatment condition.The fabricated joints demonstrated clear superconducting-to-normal transitions in self-field,with effective magnetic field screening up to 0.5 T at 20 K.To evaluate the interface between one of the MgB_(2)filaments and the MgB_(2)bulk within the joint,serial sectioning was conducted for the first time in this type of superconducting joint.The serial sectioning revealed space formation at the interface,potentially caused by the volume shrinkage associated with the MgB_(2)formation or the combined effect of the volume shrinkage and the different thermal expansion coefficients of the MgB_(2)bulk,the filament,the mold,and the sealing material.These findings are expected to be pivotal in developing MgB_(2)superconducting joining technology for MRI magnet applications through interface engineering. 展开更多
关键词 Mg B2 superconducting joint MgB_(2)conductor MRI applications Cryogen-free magnet Persistent-mode operation
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Study on joint optimization operation scheme forPangduo reservoir and Zhikong reservoir
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作者 WANG Qiang 《东北水利水电》 2018年第12期71-72,共2页
The cascade hydropower system composed of Pangduo reservoir and Zhikong reservoir are formed on the middlereach of the main Lasahe river. For giving full play of joint compensation effect of the two reservoirs, the pa... The cascade hydropower system composed of Pangduo reservoir and Zhikong reservoir are formed on the middlereach of the main Lasahe river. For giving full play of joint compensation effect of the two reservoirs, the paper studied the joint operationscheme for Pangduo reservoir and Zhikong reservoir. Based on the respective operation scheme, a reservoir group joint operationmodel is built, the model is solved by the simulation- optimization method, and then the practical and operational scheme isachieved. The scheme could give full play of the joint regulation and storage effect of the reservoir group and improve effectivelythe utilization factor of hydropower resources. 展开更多
关键词 RESERVOIR operation CASCADE RESERVOIRS joint operation SCHEME simulation OPTIMIZATION
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Autonomous process collaboration framework for C4ISR system interoperation 被引量:4
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作者 Lin Yang Minggang Yu Qingchao Dong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第6期1098-1113,共16页
Interoperability plays an important role in the joint command, control, communication, computer, intelligence, surveillance, reconnaissance(C4 ISR) operations. Coordinating and integrating operational processes to ful... Interoperability plays an important role in the joint command, control, communication, computer, intelligence, surveillance, reconnaissance(C4 ISR) operations. Coordinating and integrating operational processes to fulfill a common mission are challenged by the ever-changing battlefield and hence requires a cross-organizational process management that produces an autonomous, flexible and adaptable architecture for collaborative process evolution. The traditional business process collaboration pattern is based on the predefined "public-view" perspective and cannot meet the requirement of the joint task operations. This paper proposes a flexible visibility control mechanism and a dynamic collaboration framework for modeling and generating collaborative processes. The mechanism allows collaborators to define a set of visibility rules to generate different views of the private processes for different collaborations, which gives a great flexibility for the collaboration initiator to decide on an appropriate collaboration pattern. The framework supports collaborators to dynamically and recursively add a new process or even a new organization to an existing collaboration. Moreover, a formal representation of the processes and a set of generation algorithms are provided to consolidate the proposed theory. 展开更多
关键词 cross-organizational collaboration INTERoperABILITY collaborative process joint operations
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Simulation-optimization model of reservoir operation based on target storage curves
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作者 Hong-bin FANG Tie-song HU +1 位作者 Xiang ZENG Feng-yan WU 《Water Science and Engineering》 EI CAS CSCD 2014年第4期433-445,共13页
This paper proposes a new storage allocation rule based on target storage curves. Joint operating rules are also proposed to solve the operation problems of a multi-reservoir system with joint demands and water transf... This paper proposes a new storage allocation rule based on target storage curves. Joint operating rules are also proposed to solve the operation problems of a multi-reservoir system with joint demands and water transfer-supply projects. The joint operating rules include a water diversion rule to determine the amount of diverted water in a period, a hedging rule based on an aggregated reservoir to determine the total release from the system, and a storage allocation rule to specify the release from each reservoir. A simulation-optimization model was established to optimize the key points of the water diversion curves, the hedging rule curves, and the target storage curves using the improved particle swarm optimization (IPSO) algorithm. The multi-reservoir water supply system located in Liaoning Province, China, including a water transfer-supply project, was employed as a case study to verify the effectiveness of the proposed join operating rules and target storage curves. The results indicate that the proposed operating rules are suitable for the complex system. The storage allocation rule based on target storage curves shows an improved performance with regard to system storage distribution. 展开更多
关键词 reservoir operation joint operating rules simulation-optimization model improvedparticle swarm optimization
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深化职业教育产教融合的关键是实现跨界组织实体化运作 被引量:7
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作者 匡瑛 朱正茹 《河北大学学报(哲学社会科学版)》 2024年第2期81-92,共12页
深化产教融合是职业教育实现高质量发展的核心举措。改革开放以来,我国职业教育产教融合在政策牵引和实践演绎的相互作用下,展现了由松散到紧密、由浅层次到深层次的演变历程。但长期以来,产教“融而不合”、校企“跨而不实”的现实困... 深化产教融合是职业教育实现高质量发展的核心举措。改革开放以来,我国职业教育产教融合在政策牵引和实践演绎的相互作用下,展现了由松散到紧密、由浅层次到深层次的演变历程。但长期以来,产教“融而不合”、校企“跨而不实”的现实困境始终难以破题。伴随市域产教联合体、行业产教融合共同体等新型产教跨界组织的产生与发展,以制度突破为基本前提,推进跨界组织的实体化运作成为深化职业教育产教融合的关键。而实现这一点,需要跨界组织具有符合实际的组织结构、发挥实效的主导权力、约束有力的职责分工、稳定的利益共享机制、有效的激励保障政策,也需要多方主体协同有效的共建共治。 展开更多
关键词 产教融合 跨界组织 实体化运作 共建共治
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长江梯级水库群联合调度成效、挑战及对策 被引量:1
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作者 陈进 《长江科学院院报》 CSCD 北大核心 2024年第5期1-7,共7页
经过70 a的建设,长江流域控制性水库群基本建成。以三峡水库为核心的梯级水库群联合调度已经开展10 a。在总结控制性水库群在防洪、供水、生态和应急联合调度取得成绩的基础上,分析控制性水库群及与水网工程联合调度面临的问题和挑战,... 经过70 a的建设,长江流域控制性水库群基本建成。以三峡水库为核心的梯级水库群联合调度已经开展10 a。在总结控制性水库群在防洪、供水、生态和应急联合调度取得成绩的基础上,分析控制性水库群及与水网工程联合调度面临的问题和挑战,提出了相应的对策建议。研究表明:水库群联合调度因流域防洪调度而启,目前在防洪、抗旱供水、生态环境和应急等公益调度中发挥了重要作用。气候变化及水文中长期预报不确定性是联合调度面临的主要挑战,其次是水库群联合调度与单个水库多目标调度利益协调、定量评价调度效果及合理的补偿等管理问题。加强“四预”是解决气候变化和人类活动不确定性的主要对策。水库群与水网工程联合调度可以更广泛地发挥水利工程水安全保障作用。建立科学合理的水工程群联合调度体制和机制是解决联合调度管理问题的有效措施。 展开更多
关键词 梯级水库群 水网工程 联合调度 变化环境 应对措施
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考虑碳排放流的电-气互联系统源荷互动低碳经济调度 被引量:2
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作者 刘可真 李林耘 +3 位作者 林铮 赵庆丽 杨富宝 王玄弢 《电力自动化设备》 EI CSCD 北大核心 2024年第5期1-10,共10页
为应对电力系统存在的弃风、碳排放较高等问题,基于碳排放流理论提出了一种电-气互联系统源荷互动低碳经济调度模型。基于电力系统碳排放流计算方法,推导得到考虑气网动态特性的天然气系统碳排放流计算方法;构建以储液罐装置为主的储碳... 为应对电力系统存在的弃风、碳排放较高等问题,基于碳排放流理论提出了一种电-气互联系统源荷互动低碳经济调度模型。基于电力系统碳排放流计算方法,推导得到考虑气网动态特性的天然气系统碳排放流计算方法;构建以储液罐装置为主的储碳系统(CSS),CSS与火电机组(TU)、风电机组(WT)、电转气(P2G)设备组成TU-CSS-P2G-WT的联合运行方式;源侧以系统日运行总成本最小计算得到能源网络的碳势时空分布,荷侧根据源侧的碳势信号,基于低碳响应机制建立激励型低碳需求响应模型,合理调整用能行为最小化用户购能总成本;建立源荷互动两阶段低碳经济调度模型,并利用GUROBI进行求解。通过改进由IEEE 39节点和比利时20节点构成的电-气互联系统进行算例分析,验证了所提模型的低碳经济性和灵活性。 展开更多
关键词 碳排放流 联合运行方式 气网动态特性 激励型低碳需求响应 电碳特性
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面向战区联合作战的空间需求响应任务规划
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作者 鲁赢 李琳 +2 位作者 李翼鹏 穆冠杰 林文浩 《空军工程大学学报》 CSCD 北大核心 2024年第3期71-76,85,共7页
针对战区联合作战中的空间需求响应问题,描述了面向战区联合作战的空间需求响应任务规划的背景;从空间资源能力、空间需求响应机制、空间需求响应效益和代价等方面,分析了空间需求响应任务规划所需考虑的主要因素;定义并描述了任务规划... 针对战区联合作战中的空间需求响应问题,描述了面向战区联合作战的空间需求响应任务规划的背景;从空间资源能力、空间需求响应机制、空间需求响应效益和代价等方面,分析了空间需求响应任务规划所需考虑的主要因素;定义并描述了任务规划模型,设计了任务规划计算方法,并结合战区联合作战实际进行了案例仿真与分析,验证了模型和方法的有效性,为战区联合作战中空间需求的有效响应提供了理论和方法支撑。 展开更多
关键词 战区 联合作战 空间需求响应 任务规划
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基于元模型订单的联合作战仿真协同建模机制
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作者 李春洪 吴柱 赵晓东 《指挥信息系统与技术》 2024年第1期29-34,共6页
研究了不同层次作战实验室协同开展联合作战仿真建模的问题。分析了联合作战仿真建模需求,并运用元模型建模原理及其特点,建立了一种基于元模型订单的联合作战仿真协同建模机制。基于该机制,战役层与战术层作战实验室围绕元模型订单的... 研究了不同层次作战实验室协同开展联合作战仿真建模的问题。分析了联合作战仿真建模需求,并运用元模型建模原理及其特点,建立了一种基于元模型订单的联合作战仿真协同建模机制。基于该机制,战役层与战术层作战实验室围绕元模型订单的下发与提交,在统一作战想定下进行了元模型功能分解、参数确定、试验构建和聚合应用等活动,从而实现了联合作战协同建模。以面向海上封锁作战效能评估的联合作战仿真建模为例,验证了该机制的有效性。 展开更多
关键词 联合作战 元模型 订单 协同建模
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双轨正性暗示在发育性髋关节发育不良患者手术室等候期间的应用研究
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作者 杨佳 谢美英 邓刚 《罕少疾病杂志》 2024年第6期104-106,共3页
目的 探讨双轨正性暗示在发育性髋关节发育不良(DDH)患者手术室等候期间的应用效果。方法 选取医院2021年8月-2023年10月拟行手术治疗的DDH患者108例,以随机数字表法分为对照组(54例)、观察组(54例);对照组于手术室等候期间行常规护理,... 目的 探讨双轨正性暗示在发育性髋关节发育不良(DDH)患者手术室等候期间的应用效果。方法 选取医院2021年8月-2023年10月拟行手术治疗的DDH患者108例,以随机数字表法分为对照组(54例)、观察组(54例);对照组于手术室等候期间行常规护理,研究组基于对照组行双轨正性暗示护理;对比两组生理应激反应、焦虑程度、心理等候时间及满意度。结果 观察组麻醉成功时心率(HR)、平均动脉压(MAP)较对照组低,差异有统计学意义(P<0.05);观察组入手术室时、术后1d焦虑自评量表(SAS)评分较对照组低,差异有统计学意义(P<0.05);观察组心理等候时间较对照组短,总满意度较对照组高,差异有统计学意义(P<0.05)。结论 DDH患者手术室等候期间采用双轨正性暗示护理可减轻生理应激反应,改善焦虑程度,缩短心理等候时间,提高满意度。 展开更多
关键词 发育性髋关节发育不良 双轨正性暗示 手术室等候期间 应激反应 焦虑
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超深井射孔冲击动载荷引起封隔器断裂失效分析
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作者 练章华 万智勇 +2 位作者 王飞文 赵朝阳 史君林 《天然气工业》 EI CAS CSCD 北大核心 2024年第6期44-51,共8页
中国超深层油气资源丰富,超深井油气开发过程中常采用一体化管柱完成射孔—试油—酸化三联作业,作业过程中超深井射孔冲击动载荷频繁导致封隔器断裂失效。为解决上述问题,基于弹塑性有限元法,结合实际井下测得的射孔管串起爆瞬态冲击动... 中国超深层油气资源丰富,超深井油气开发过程中常采用一体化管柱完成射孔—试油—酸化三联作业,作业过程中超深井射孔冲击动载荷频繁导致封隔器断裂失效。为解决上述问题,基于弹塑性有限元法,结合实际井下测得的射孔管串起爆瞬态冲击动力学载荷边界条件,开展了新疆某地X1井射孔作业RTTS封隔器(全开式挂壁封隔器)—减震器管串瞬态冲击动力学有限元仿真分析,建立了减震器二阶带阻尼的质量—弹簧力学系统模型,从理论上对比分析了双减震器的减震效果与有限元分析结果的可靠性。研究结果表明:(1)在射孔爆轰0.09 s和0.21 s时刻,中心管接头螺纹处分别出现805.4 MPa和925.1 MPa两个应力峰值,超过了管材的屈服强度和抗拉强度,且冲击波引起的交变应力导致局部位置开始发生裂纹失效,裂纹逐渐扩展到整个截面,造成螺纹接头断裂;(2)根据仿真模型计算结果以及中心管结构尺寸分析,发现其螺纹部分结构尺寸偏小,导致峰值应力超过其抗拉强度造成断裂失效;(3)建议采用中心管上部螺纹连接处镦粗2~3 mm的改进方案,其最大应力可降低27%以上,可明显提高结构强度;(4)使用双减震器能有效降低射孔管串上部冲击载荷,理论计算指出双减震器比单减震器的振幅降低约50%,其最大应力降低约42%。结论认为,研究成果可为超深井RTTS封隔器管柱安全射孔作业提供理论和技术支撑,并将有力推动我国超深层油气资源的高效勘探开发。 展开更多
关键词 超深井 射孔作业 封隔器断裂 减震器 公螺纹接头 冲击载荷 数值模拟
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数字经济下农村物流共同配送运营模式研究
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作者 宾厚 徐晶晶 王素杰 《物流研究》 2024年第1期18-22,共5页
随着我国数字乡村建设和电子商务向农村的深入,农村物流正向高质量发展转变。本文采用案例分析法研究数字经济下我国农村物流共同配送模式的运行流程及运营现状,发现其中存在产业结构不合理、基础设施落后、配送资源缺乏共享等问题。针... 随着我国数字乡村建设和电子商务向农村的深入,农村物流正向高质量发展转变。本文采用案例分析法研究数字经济下我国农村物流共同配送模式的运行流程及运营现状,发现其中存在产业结构不合理、基础设施落后、配送资源缺乏共享等问题。针对上述问题,提出设立共同配送管理机构、加强物流基础设施建设、打造物流共同配送联盟等发展性建议,以期解决数字经济下我国农村物流共同配送难题。 展开更多
关键词 数字经济 农村物流 共同配送 运营模式
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基于任务优先权的军民航飞行活动协同排序模型
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作者 张兆宁 杨雯 《中国民航大学学报》 CAS 2024年第2期23-29,共7页
随着空域资源需求的不断增大,军民航间飞行矛盾日益突显。为解决此问题,本文以国务院、中央军事委员会空中交通管制委员会提出的“军民航空管联合运行”为背景,引入军民航共享空域的概念,重点研究了在此类空域中军民航飞行活动协同排序(... 随着空域资源需求的不断增大,军民航间飞行矛盾日益突显。为解决此问题,本文以国务院、中央军事委员会空中交通管制委员会提出的“军民航空管联合运行”为背景,引入军民航共享空域的概念,重点研究了在此类空域中军民航飞行活动协同排序(CMFCS,civil-military aviation flight activity collaborative sequencing)问题。首先,基于军民航各自飞行任务特点与差异,对军民航飞行任务的种类进行划分,并使用层次分析法确定各类飞行任务的优先权原则;其次,以军民航飞行活动总延误时间成本最小为目标,建立CMFCS模型;最后,使用遗传算法对模型进行求解,确定军民航飞行活动批准进入共享空域的时间序列。研究结果表明,与经典的先到先服务(FCFS,first come first service)策略相比,协同排序策略得到的总延误时间成本降低了72.17%,优化效果显著且更符合实际,能够实现军民航共同使用国家空域资源,保障飞行活动安全、有序、高效地运行。 展开更多
关键词 空中交通流量管理 军民航空管联合运行 飞行活动协同排序 遗传算法
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玉米秸秆混埋联合作业机的研制与试验
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作者 班春华 姜国明 付冰 《农业科技与装备》 2024年第3期46-48,共3页
秸秆粉碎还田是一种环保且高效的农业技术,能够改善土壤结构,提高土壤的透气性和保水性,减少化肥和农药的使用量,降低农业生产成本,减轻对环境的压力。以秸秆粉碎后混埋地下技术为核心,设计一种玉米秸秆混埋联合作业机,通过田间试验来... 秸秆粉碎还田是一种环保且高效的农业技术,能够改善土壤结构,提高土壤的透气性和保水性,减少化肥和农药的使用量,降低农业生产成本,减轻对环境的压力。以秸秆粉碎后混埋地下技术为核心,设计一种玉米秸秆混埋联合作业机,通过田间试验来验证机具的性能和作业效果。结果表明,秸秆粉碎混埋作业机可以提高玉米秸秆资源化利用效率,为推动农业可持续发展提供参考。 展开更多
关键词 玉米秸秆 混埋联合作业机 秸秆还田 机具设计
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