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Feature Solution in the Process of Parameterizing Port Model
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作者 彭禹 郝志勇 +2 位作者 孙秀永 刘东航 付鲁华 《Transactions of Tianjin University》 EI CAS 2004年第2期118-125,共8页
Aimed at attaining to an integrated and effective pattern to guide the port design process, this paper puts forward a new conception of feature solution, which is based on the parameterized feature modeling. With this... Aimed at attaining to an integrated and effective pattern to guide the port design process, this paper puts forward a new conception of feature solution, which is based on the parameterized feature modeling. With this solution, the overall port pre-design process can be conducted in a virtual pattern. Moreover, to evaluate the advantages of the new design pattern, an application of port system has been involved in this paper; and in the process of application a computational fluid dynamic analysis is concerned. An ideal effect of cleanness, high efficiency and high precision has been achieved. 展开更多
关键词 feature solution port modeling PARAMETERIZATION port computational fluid dynamics internal-combustion engine intake-exhaust system
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Multi-port cavity model and low-level RF systems design for VHF gun 被引量:3
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作者 Kui Liu Lin Li +2 位作者 Cheng Wang Qiang Gu Ming-Hua Zhao 《Nuclear Science and Techniques》 SCIE CAS CSCD 2020年第1期80-87,共8页
Very high frequency(VHF) photocathode guns have excellent performance and are being increasingly selected as electron sources for high-repetition-rate X-ray free-electron lasers. As a highly loaded quality factor cavi... Very high frequency(VHF) photocathode guns have excellent performance and are being increasingly selected as electron sources for high-repetition-rate X-ray free-electron lasers. As a highly loaded quality factor cavity, the VHF gun requires high stability in the amplitude and phase of the cavity field. However, the gun is microwave powered by two solid-state power sources through two separate power couplers. The input difference between the two power couplers will influence the stability of the cavity field. To systematically study this influence and obtain measurement formulae, a multi-port VHF gun LCR circuit model is built and analyzed. During the warm-up condition, the cavity structure will be deformed due to the large-scale change in the cavity temperature. Then, the deformation will result in cavity resonant frequency changes. To prevent the mechanic tuner from suffering damages due to the frequent and long-distance movement for correcting the cavity resonant frequency, a self-excited loop(SEL) control system is considered for changing the loop phase and make the loop frequency follow the resonant frequency. In this study, a steady-state model of the VHF gun cavity is built for obtaining the optimal input coupler coefficient and the stability requirement of the forward voltage. Then, the generator-driven resonator and SEL control system, which combine with the VHF multiport modeling, are modeled and simulated. The simulated results show that the SEL system can perfectly operate in the process of condition and warm-up. 展开更多
关键词 VHF photocathode gun Multi-port modeling Self-excited loop LLRF control
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Three-Dimensional Model Test for Port Engineering with Multi-Directional Waves 被引量:1
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作者 Yu Yuxiu Liu Shuxue Professor, State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology (DUT), Dalian 116024 Assistant Researcher, State Key Laboratory of Coastal and Offshore Engineering, DUT, Dalian 116024 《China Ocean Engineering》 SCIE EI 1994年第1期51-66,共16页
-The necessity of using irregular waves, especially multi- directional waves to conduct three-dimensional model tests for port engineering and the test method are described in this paper through an example of model te... -The necessity of using irregular waves, especially multi- directional waves to conduct three-dimensional model tests for port engineering and the test method are described in this paper through an example of model test for a port. The test results show that a deep navigation channel has a large effect on the waves in front of the breakwater near the port entrance and on the wave condition in the port. 展开更多
关键词 port engineering three-dimensional model test irregular waves multi-directional waves
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Environmental stress model for evaluation of vessel traffic in ports and waterways
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作者 HU Zhiwu CHEN Weijiong INOUE K 《上海海事大学学报》 北大核心 2005年第3期35-39,共5页
Environmental stress model is proposed as an effective tool to the analysis and evaluation of navigational safety in ports and waterways. Marine traffic simulations are carried out in a virtual port area with various ... Environmental stress model is proposed as an effective tool to the analysis and evaluation of navigational safety in ports and waterways. Marine traffic simulations are carried out in a virtual port area with various arrangements and conditions. Calculations of stress values and traffic volume criteria are illustrated. The simulation results provide a valuable hint for safety management of vessel traffic. The model provides quantitative information and helps administrators in decision making to achieve desired safety level and improve the efficiency of vessel traffic in ports and waterways. 展开更多
关键词 船舶 港口 水路 环境压力模型 交通管理
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Numerical model for sedimentation in the access channel and harbor basin of Belawan Port
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作者 Hang Tuah. Salim 《水道港口》 2010年第5期321-321,共1页
Belawan is the largest port serving North Sumatra for the import and export.Port has facilities for handling container,CPO liquid bulk cargo,Oil,and other agriculture products.Its location is at the river mouth which ... Belawan is the largest port serving North Sumatra for the import and export.Port has facilities for handling container,CPO liquid bulk cargo,Oil,and other agriculture products.Its location is at the river mouth which is subjected to the heavy sedimentation especially after many deforestation activities in its catchment area. The numerical modeling was developed for predicting the rate of sediment caused by erosion in the catchment area for several scenarios.This predicted rate of sediment was applied as input to model of sedimentation in the ocean.Present condition of sedimentation data was used as calibrated data.This integrated model was used to simulate the sedimentation in Belawan access channel and harbor basin for several development plans. 展开更多
关键词 numerical model SEDIMENTATION Belawan port
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The Selection of Dry Port Location by Analytic Network Process Model: A Case Study of Dosso-Niger
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作者 Hamadou Tahirou Abdoulkarim Seydou Harouna Fatouma Bomboma Kalgora 《Journal of Transportation Technologies》 2019年第2期146-155,共10页
The aim of this paper is to select the best location for the construction of a dry port in Niger which is a land locked country (LLC). Niger is located in the Sahel and has a land area of 1,267,000 square kilometers [... The aim of this paper is to select the best location for the construction of a dry port in Niger which is a land locked country (LLC). Niger is located in the Sahel and has a land area of 1,267,000 square kilometers [1], with the closest port being port of Cotonou in Benin. The transport corridor from Niamey to Cotonou is approximately 1036 km long [2]. It is estimated that this corridor carries about 40 percent of Niger’s overseas trade traffic [3]. In this work, the Analytic Network Process (ANP) model is used to determine the optimal location of the dry port, among three major cities: Niamey (capital city), Dosso and Gaya. From the application of this selection model, Dosso was selected as the best location for the location of the dry port, while Gaya and Niamey were placed second and third respectively. The results obtained in this work strongly confirm the decision of the government of Niger to construct a dry port in Dosso, a project that commenced in 2010 and is still in progress. 展开更多
关键词 DRY port Localization ANALYTIC Network Process (ANP) model
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自发性气胸单孔胸腔镜手术后肺部并发症预测模型的构建 被引量:2
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作者 王永平 王辉 +4 位作者 郑翔 闻作川 田浩 陈鹏 刘冠群 《腹腔镜外科杂志》 2024年第5期321-325,共5页
目的:探讨自发性气胸单孔胸腔镜手术后肺部并发症预测模型的构建。方法:选取2021年5月至2022年5月行单孔胸腔镜手术的106例自发性气胸患者,根据术后是否发生肺部并发症将患者分为并发症组(n=22)与无并发症组(n=84)。对两组患者临床资料... 目的:探讨自发性气胸单孔胸腔镜手术后肺部并发症预测模型的构建。方法:选取2021年5月至2022年5月行单孔胸腔镜手术的106例自发性气胸患者,根据术后是否发生肺部并发症将患者分为并发症组(n=22)与无并发症组(n=84)。对两组患者临床资料进行单因素与多因素分析,筛选出影响术后肺部并发症的危险因素,并构建列线图预测模型。结果:并发症组患者年龄、吸烟史、合并肺部疾病、胸膜粘连严重、肺大疱数量、术后24 h疼痛分级、术中出血量高于无并发症组,术前白蛋白水平低于无并发症组。多因素Logistic回归分析结果显示,年龄≥50岁(OR=1.240,95%CI=1.064~1.445)、合并肺部疾病(OR=26.154,95%CI=1.224~558.648)、胸膜粘连严重(OR=23.289,95%CI=2.940~184.520)、肺大疱数量>2个(OR=2.878,95%CI=1.787~4.633)是影响术后肺部并发症的独立危险因素(P<0.05)。根据以上危险因素建立预测模型预测术后肺部并发症的受试者工作特征曲线下面积为0.82(95%CI=0.756~0.874),敏感度与特异度分别为82.33%与65.47%。结论:年龄、合并肺部疾病、胸膜粘连严重、肺大疱数量是影响自发性气胸单孔胸腔镜手术后肺部并发症的独立危险因素,根据其构建的列线图预测模型对术后肺部并发症的发生风险具有较好的预测价值。 展开更多
关键词 自发性气胸 胸腔镜检查 单孔 术后肺部并发症 预测模型
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MATHEMATICAL MODEL FOR WAVE DIFFRACTION WITH ARBITRARY RATE OF REFLECTION
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作者 Chongzhun, Gong Changkuan, Zhang 《China Ocean Engineering》 SCIE EI 1989年第2期141-151,共11页
The boundaries of a natural harbor or artificial harbor are very complex as far as its shape and reflection condition are concerned. The schemes available for solving wave diffraction in a harbor are not very accurate... The boundaries of a natural harbor or artificial harbor are very complex as far as its shape and reflection condition are concerned. The schemes available for solving wave diffraction in a harbor are not very accurate due to the simplification of realistic boundaries into a single jetty, a gap breakwater and a detached breakwater, neglecting the reflection effect of boundaries along the quays and the shore line whose shapes are rather irregular. Physical models turn to be quite helpful and valid in this case. In the present paper a mathematical model for wave diffraction in a harbor is introduced by using the singularity distribution method which can take into account the boundaries with arbitrary rate of reflection. The present model has been applied to the estimation of wave diffraction in the harbor basin of Guangdong Dayawan Nuclear Plant, and verifications with corresponding physical models are quite favorable. 展开更多
关键词 Mathematical models Nuclear Power Plants ports and Harbors
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Air Emission Inventories Methodology for Port and Air Quality Simulation
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作者 Bang Q. Ho 《现代交通(中英文版)》 2013年第1期1-9,共9页
关键词 空气质量模型 港口起重机 空气排放 模拟 空气污染物浓度 污染物排放总量 单方 排放清单
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Assessment of Dry Port Efficiency in Africa Using Data Envelopment Analysis
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作者 Hamadou Tahirou Abdoulkarim Seydou Harouna Fatouma Hamadou Tahirou Hassane 《Journal of Transportation Technologies》 2019年第2期193-203,共11页
This work involves the evaluation of dry port competitiveness through analysis of efficiencies for selected dry ports in Africa. Five dry ports were selected and analysis carried out over a period of four years. The d... This work involves the evaluation of dry port competitiveness through analysis of efficiencies for selected dry ports in Africa. Five dry ports were selected and analysis carried out over a period of four years. The dry ports considered were Mojo and Kality in Ethiopia, Mombasa in Kenya, Isaka in Tanzania and Casablanca in Casablanca, Morocco. Data Envelopment Analysis (DEA) was applied for this work. Container throughputs for the various ports under consideration were used as the output variable for the data analysis model, while the number of reach stackers, the number of tractors, the number of forklifts and the size of the dry port were used as the input variables. From the results, the Mombasa dry port was found to be the most efficient with an average score of approximately 1 over the period under consideration. Casablanca was the second efficient dry port with an average score of 0.762, while Isaka was the least efficient with an average score of 0.142. This research is significant since the African countries have embraced the dry port concept, as witnessed in the huge investments in this sector, and would serve to highlight areas that need improvement for the few existing dry port facilities, most of which are undergoing expansion as well as modernization. 展开更多
关键词 DRY port DRY port EFFICIENCY DRY port Evaluation Data Envelopment Analysis (DEA) model
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柔性直流输电系统三端口混合参数建模及其稳定性分析
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作者 刘欣 袁易 +2 位作者 王利桐 贾焦心 孙海峰 《电工技术学报》 EI CSCD 北大核心 2024年第16期4968-4984,共17页
模块化多电平换流器(MMC)与系统网络之间的交互是诱发振荡的主要原因,然而现有MMC单侧阻抗/导纳建模方法往往没有计及对端换流站的动态过程,因此该文重点通过建立可以考虑交直流耦合的换流器三端口混合参数模型实现整个双端柔直系统的... 模块化多电平换流器(MMC)与系统网络之间的交互是诱发振荡的主要原因,然而现有MMC单侧阻抗/导纳建模方法往往没有计及对端换流站的动态过程,因此该文重点通过建立可以考虑交直流耦合的换流器三端口混合参数模型实现整个双端柔直系统的稳定性分析。首先,该文基于谐波状态空间法推导考虑桥臂间谐波动态交互过程的MMC换流器交直流端口功率守恒方程,并据此建立换流器的三端口混合参数模型;其次,基于所建立的三端口混合参数模型和广义奈奎斯特判据,对MMC互联系统的稳定性进行分析,因该方法可避免计算开环传递函数右半平面零极点的数量,与传统单侧阻抗稳定性分析方法相比,可实现系统稳定性的准确判断;再次,推导了特征值相位关于三端口混合参数元素的灵敏度计算公式,揭示了系统振荡的诱因,进一步结合控制参数灵敏度分析,实现了一种用于改善互联系统直流侧稳定性的直流电流前馈附加阻尼控制策略;最后,结合时域仿真算例验证了稳定性分析和改善措施的有效性。 展开更多
关键词 模块化多电平换流器 三端口网络 混合参数模型 稳定性分析 谐波状态空间
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基于改进灰色预测模型的港口物流需求预测研究——以上海港为例
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作者 柳德才 张世林 《物流科技》 2024年第15期75-79,共5页
随着疫情防控政策的调整,我国外贸行业呈现快速增长态势。文章基于改进的灰色预测NGMG 1,(N)模型,运用MATLAB软件,以上海港2013至2022年的集装箱吞吐量为原始数据,预测未来五年上海港的集装箱吞吐量,并对改进的灰色NGMG 1,(N)模型预测... 随着疫情防控政策的调整,我国外贸行业呈现快速增长态势。文章基于改进的灰色预测NGMG 1,(N)模型,运用MATLAB软件,以上海港2013至2022年的集装箱吞吐量为原始数据,预测未来五年上海港的集装箱吞吐量,并对改进的灰色NGMG 1,(N)模型预测结果进行精度检验,结果显示该模型预测精度较高。最后基于预测结果,分析上海港未来五年物流需求趋势向好的主要原因并得出结论。 展开更多
关键词 灰色预测 NGMG 1 (N)模型 港口物流 需求预测
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煤炭港口数字孪生系统构建及应用
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作者 毕磊 郭享 +1 位作者 柳海宇 刘春泽 《水运工程》 2024年第5期185-192,共8页
针对当前煤炭港口数字化转型相关研究及实践中存在的技术应用场景比较单一、对全链条全场景覆盖度不够、子系统存在信息孤岛等问题,进行煤炭港口数字孪生系统构建及应用研究。基于对煤炭港口场景的深入了解和运营实践,采用物联网、系统... 针对当前煤炭港口数字化转型相关研究及实践中存在的技术应用场景比较单一、对全链条全场景覆盖度不够、子系统存在信息孤岛等问题,进行煤炭港口数字孪生系统构建及应用研究。基于对煤炭港口场景的深入了解和运营实践,采用物联网、系统仿真等关键技术,在已有研究的基础上实现数据标准化和接口标准化,提出涵盖全要素、全流程、全场景的煤炭港口数字孪生架构和五维模型。依托某煤炭港口进行应用,系统实现了全面准确反映港口运营情况、规避煤炭自燃安全隐患、大幅提升运营效率的目标。 展开更多
关键词 煤炭港口 数字孪生 五维模型 智慧运营
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Research on the Development Strategy of Ningbo Transportation Port &Shipping Industry
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作者 Ningyu Zhang 《Journal of Transportation Technologies》 2019年第4期474-488,共15页
Firstly, the development background of Ningbo Transportation Port & Shipping Industry is analyzed on a spatial scale. Based on that, the strategic goal of Ningbo transportation port Port & Shipping Industry is... Firstly, the development background of Ningbo Transportation Port & Shipping Industry is analyzed on a spatial scale. Based on that, the strategic goal of Ningbo transportation port Port & Shipping Industry is put forward, and strategic path analysis of strategic objectives is carried out. Finally, with the dynamic resource view, the strategic integration model of Ningbo Port & Shipping Industry is proposed. 展开更多
关键词 TRANSportATION port & SHIPPING Development Strategy Dynamic RESOURCE VIEW Integrated model
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海南自贸港建设进程中人民获得感理论模型与量表编制
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作者 邓彩艳 金盈楹 +3 位作者 高舒雅 杨倩颖 刘伟方 王瑛琦 《中国健康心理学杂志》 2024年第4期567-574,共8页
目的:旨在构建海南自贸港建设进程中人民获得感的理论模型并编制适合的获得感量表。方法:通过文献分析建构人民获得感的理论模型并通过开放式问卷和专家咨询编制量表初测问卷题项,然后分别进行了初测和正式施测,并对问卷数据进行统计分... 目的:旨在构建海南自贸港建设进程中人民获得感的理论模型并编制适合的获得感量表。方法:通过文献分析建构人民获得感的理论模型并通过开放式问卷和专家咨询编制量表初测问卷题项,然后分别进行了初测和正式施测,并对问卷数据进行统计分析,进而验证理论模型的拟合度并确定海南自贸港建设进程中人民获得感的正式量表。结果:(1)本研究进行探索性因子分析得出人民获得感的5个因子:经济获得感、政治获得感、社会获得感、文化获得感、生态获得感,累积解释总变异的65.008%;(2)正式量表包含5个维度30个题项,验证性因子分析表明,人民获得感五因子结构模型拟合良好(χ^(2)/df=2.93,P<0.001,TLI=0.923,CFI=0.930,RMSEA=0.057);(3)量表的Cronbach’s α为0.957,5个维度的Cronbach’s α分别为0.897、0.838、0.896、0.801、0.913,量表具有良好的内部一致性;(4)量表各维度之间相关系数小于维度与总分之间的相关系数,各维度具有一定的独立性又具有一致性,量表具有较好的结构效度。结论:正式量表具有较好的信度和效度,可以用来评估海南自贸港建设进程中人民的获得感,对提升人民获得感有一定的指导意义。 展开更多
关键词 海南自贸港建设 人民获得感 理论模型 量表编制
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集装箱货运网络优化问题的研究——以宁波舟山港集装箱运输为例
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作者 杨德志 邵杰 《辽东学院学报(自然科学版)》 CAS 2024年第1期70-76,共7页
为优化集装箱货运网络,对进出口货运集装箱装卸中转站的最佳地理位置的选择和集装箱运输计划的设计进行了研究。2个问题同时考虑建设成本、运输成本以及存储、运力等因素,建立了一种集装箱货运网络优化模型。利用国际集装箱货运代理公... 为优化集装箱货运网络,对进出口货运集装箱装卸中转站的最佳地理位置的选择和集装箱运输计划的设计进行了研究。2个问题同时考虑建设成本、运输成本以及存储、运力等因素,建立了一种集装箱货运网络优化模型。利用国际集装箱货运代理公司在宁波舟山港一整年的船期数据,使用LINGO软件对所建模型的效果进行求解。最终从宁波舟山港腹地现有38个存储中转仓中优选出32个中转仓存储集装箱,使大约5%的集装箱通过铁路运输,从而能节省5.74%的运营成本。 展开更多
关键词 宁波舟山港 网络设计 集装箱运输 优化模型
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干散货码头数字孪生综合管控平台架构与实践 被引量:3
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作者 李林 张钊 +1 位作者 范垂荣 鲁东起 《水运工程》 2024年第1期189-195,共7页
为加快干散货智慧港口建设,探讨了数字孪生技术在干散货码头中的应用。分析干散货码头运营呈现出的自动化、信息化、智能化发展趋势,指出当前面临的数据爆炸性增长、数据采集不全面等挑战。在此基础上,对数字孪生在港口的应用领域进行... 为加快干散货智慧港口建设,探讨了数字孪生技术在干散货码头中的应用。分析干散货码头运营呈现出的自动化、信息化、智能化发展趋势,指出当前面临的数据爆炸性增长、数据采集不全面等挑战。在此基础上,对数字孪生在港口的应用领域进行分析梳理,围绕数字孪生模型内容,提出7大应用业务领域。通过干散货码头数字孪生的建设路线,提出以数据驱动和模型驱动为核心的数字孪生模型构建方法。结合干散货码头智能化建设现状,提出干散货码头数字孪生平台架构方案。选取典型门机设备和港区全局典型案例,分别从微观设备孪生构建和宏观全局孪生场景两个层面阐述应用实践经验,以期为智慧港口的发展与建设提供参考。 展开更多
关键词 智慧港口 干散货码头 数字孪生 数据驱动 模型驱动
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自贸港视域下洋浦港港口物流竞争力的波特五力研究
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作者 丁琪 《物流科技》 2024年第17期75-77,共3页
文章利用波特五力模型,对洋浦港港口物流的现有竞争者的竞争力、购买者讨价还价能力、潜在竞争者威胁、替代品的替代能力、供应商的讨价还价能力五个方面进行分析,明确洋浦港港口物流发展所处的竞争环境,提出适应于洋浦港港口物流发展... 文章利用波特五力模型,对洋浦港港口物流的现有竞争者的竞争力、购买者讨价还价能力、潜在竞争者威胁、替代品的替代能力、供应商的讨价还价能力五个方面进行分析,明确洋浦港港口物流发展所处的竞争环境,提出适应于洋浦港港口物流发展的措施,以此提高其港口物流竞争力。 展开更多
关键词 港口物流 港口竞争力 洋浦港 波特五力模型
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CAGD AND NC MILLING OF THE CASTING MOULD OF HELICAL INTAKE PORT
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作者 Ma Xiangyang Qi Wenxing(Shanghai Institute of Railway Technology)Zou Huijun(Shanghai Jiaotong University) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 1994年第3期219-224,共17页
A new method of the design and machining the casting moulds of helical intake ports of diesel engines is presented based on CAD / CAM technique. The problems about the smooth continuity between patches, the cutter int... A new method of the design and machining the casting moulds of helical intake ports of diesel engines is presented based on CAD / CAM technique. The problems about the smooth continuity between patches, the cutter interference and the determination of the mould split curve are discussed in details.The CAGD system of the intake port has been developed. and the casting mould is machined sucessfully on NC machine. 展开更多
关键词 Geometric modelling Continuity between patches Cutter interference Intake port NC machining
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考虑生态限制的内河港口岸线等级评价研究
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作者 蒋军 陈丽璇 +2 位作者 杨琛 马志明 林丽 《交通运输研究》 2024年第1期70-81,共12页
为明晰港口岸线的优劣情况,给港口开发及整合提供参考,提出了一种考虑生态限制条件的港口岸线等级评价方法。首先,选取自然条件、社会经济、交通发展等3个方面的12个指标,借助物元可拓模型进行港口岸线资源等级初评。然后,以生态限制条... 为明晰港口岸线的优劣情况,给港口开发及整合提供参考,提出了一种考虑生态限制条件的港口岸线等级评价方法。首先,选取自然条件、社会经济、交通发展等3个方面的12个指标,借助物元可拓模型进行港口岸线资源等级初评。然后,以生态限制条件为减分因素对初评结果进行修正,得出岸线等级可划分为4类:一级规划岸线、二级规划岸线、三级规划岸线、四级规划岸线。其中,一级规划岸线最适宜建设深水港,二级规划岸线适宜建港,三级规划岸线和四级规划岸线不宜建港。最后,基于长江重庆段五段不同岸线的数据进行案例分析,分析结果表明:评价结果与实际情况基本一致;改进的等级评价指标、定性定量相结合的方法能够提高评价结果的准确性;将生态因素作为限制条件从综合评价中独立出来进行等级结果修正能够有效避免岸线开发利用时侵占生态资源。 展开更多
关键词 水路运输 内河港口岸线 物元可拓模型 生态限制 等级评价
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