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排序方式: 共有162条查询结果,搜索用时 31 毫秒
1.
范娜娜 《广东交通职业技术学院学报》2020,(1):51-54
物业管理作为一个新型的服务行业,近年来随着城市化迅猛建设而呈现高速发展的态势,对现代城市物业管理服务现有的模式进行分析,探索物业管理服务模式的特点,发现其中的问题所在,进一步挖掘物业管理服务企业在各方面多元的服务潜力,物业管理服务企业与业主共同协作延伸增值服务空间,缓解双方之间的矛盾,促进物业管理服务的发展。 相似文献
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Benthic community patterns reflect water column processes in the Northeast Water polynya (Greenland)
Dieter Piepenburg William G. Ambrose Jr. Angelika Brandt Paul E. Renaud Michael J. Ahrens Preben Jensen 《Journal of Marine Systems》1997,10(1-4)
Benthic community patterns were investigated in the Northeast Water polynya (Greenland) during the summers of 1992 and 1993 to elucidate to what extent the bottom fauna is influenced by the dynamics of the overlying water. Five different fractions of the benthos (foraminiferans, nematodes, polychaetes, peracarid crustaceans, and epibenthic megafauna), ranging in average adult body size over 6 orders of magnitude (from about 100 μm to about 10 cm), were sampled quantitatively at 69 stations in water depths from 40 to 515 m. Total abundances of nematodes, polychaetes and peracarid crustaceans were found to be primarily correlated with parameters characterizing the potential benthic food supply (water column pigment and nitrate concentrations, sediment bound pigments and sediment biological activity), whereas abundances of foraminiferans and megabenthos were largely associated with seabed properties. Four benthic zones were distinguished by separately analyzing the faunistic composition and distribution of the five community fractions for Ob Bank, Western Westwind Trough, Eastern Westwind Trough, and Belgica Trough. This pattern was shown principally to reflect pelagic regimes differing in surface water hydrography, ice cover and euphotic productivity. This is the first time that a synoptic study of several benthic community portions spanning such a range in sizes and life styles has been performed in a polar shelf ecosystem. Our results indicate that abundances as well as composition of Arctic benthos are largely influenced by mesoscale pelagic processes, and thus provide further evidence for the importance of the benthic-pelagic coupling in high latitude seas. 相似文献
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中国古代渔船源远流长,由原始浮具发展为筏与独木舟,而后又发展成为“木板船”、“木帆船”。我国北线的沙船和南线的福船两大基本船型,主要是由筏和独木舟演变发展而来,对世界造船技术的发展作出了独特的贡献,对我国渔业、航海的发展,起了不可磨灭的作用。 相似文献
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简要介绍202kW玻璃钢拖网渔船的总体结构和主要技术参数,并就船电设计有关的电制、电站、配电、动力、报警装置、防无线电干扰措施、避雷、接地保护、电缆选用、无线电通信、导航、助渔设备配备等问题作了系统阐述。 相似文献
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《Maritime Policy and Management》2012,39(8):957-966
ABSTRACTMaritime shipping necessitates flexible and cost-effective port access worldwide through the global shipping network. This paper presents an efficient method to identify major port communities, and analyses the network connectivity of the global shipping network based on community structure. The global shipping network is represented by a signless Laplacian matrix which can be decomposed to generate its eigenvectors and corresponding eigenvalues. The largest gaps between the eigenvalues were then used to determine the optimal number of communities within the network. The eigenvalue decomposition method offers the advantage of detecting port communities without relying on a priori assumption about the number of communities and the size of each community. By applying this method to a dataset collected from seven world leading liner shipping companies, we found that the ports are clustered into three communities in the global container shipping network, which is consistent with the major container trade routes. The sparse linkages between port communities indicate where access is relatively poor. 相似文献
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对于渔船避让的几点见解 总被引:2,自引:0,他引:2
阐述了大连——日本航线上经常遇到的渔船种类及作业特点,总结出针对不同种类的渔船在捕捞过程中应采取的必要措施,为以后在该航线上行驶的远洋船舶驾驶人员提供经验借鉴。 相似文献
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针对我国远洋渔船装备落后、操纵性差、机舱环境恶劣、电站管理水平低、劳动强度大以及渔船机舱自动化水平低等问题,介绍里海远洋渔船无人机舱系统的设计与组成。通过采用主机遥控系统、电站功率管理系统、机舱监测报警系统以及网络通信等技术,将自动化、电气化、信息化和智能化控制技术等船舶前沿科技应用于实船,构建一个满足法国船级社(BV)机舱自动化最高等级AUT-UMS要求的无人机舱系统,以提高远洋渔船的操控性、安全性和可靠性,提升供电系统自动化管理水平,改善作业人员工作环境。对该自动化系统的效果和特点进行分析,结果可为我国远洋渔船自动化系统的研究提供策略和思路。 相似文献
9.
渔港是沿海渔区渔船生产、航行,停泊安全的重要基础保障.为加强渔港安全管理、促进渔业经济发展和新农村建设,在研究渔港功能、渔港安全监控和信息管理系统现状的基础上,对船舶动态监控、船岸通信、综合信息管理3个子系统的设计原理和实现途径,对数据接受和处理,船舶动态数据库,目标船化标绘系统,基于AIS(Automatic Identification System)数据的智能船舶动态视频监控4个核心技术问题逐一进行了论述.系统的设计和研发达到了国家中心渔港的建设要求,并满足了渔港安全管理的需要. 相似文献
10.
Kenneth Wieand 《Coastal management》2013,41(2):208-223
The study develops a model of recreational fish catch probabilities, based on angler fishing strategies, that is conditional on uncertain information about the coastal ocean environment. We calculate expected catch based on a hypothetical Baseline Data Set and hypothetical data from an Integrated Ocean Observation System (IOOS) to demonstrate potential benefits from IOOS. The role of Bayesian probabilities in Random Utility Models of recreational fishing is identified. The study discusses the types of information that will be required by recreational anglers in the Gulf of Mexico. Results have implications for the construction of ocean observation systems for recreational fishermen. 相似文献