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1.
《Coastal Engineering》2007,54(6-7):493-505
This contribution evaluates the application of coastal video systems to monitoring and management of coastal stability problems on sandy coastlines. Specifically, video-derived parameters (coastal state indicators or CSIs) are developed which facilitate the measurement of the shoreline evolution (erosion/accretion) and response to storms, seasonal cycles and anthropogenic interventions like beach/shoreface nourishment and dredging. The primary variable which forms the basis for all the CSIs discussed in this contribution is the shoreline position derived from time-averaged video images. These waterlines are used to generate secondary products including shoreline contours at a constant pre-defined level, (intertidal) beach volumes, and momentary shoreline positions which reflect the sand volume in a meter wide section of the intertidal coast. Video-derived coastal state indicators were verified via comparisons with traditional topographical/bathymetric surveying techniques and a good agreement was found in all cases. CSIs were computed for three contrasting sandy coastal environments including an unprotected natural beach, a protected beach and a spit. Firstly, results are presented which demonstrate the advantages of coastal video systems over and above infrequent traditional topographic/bathymetric surveying methods. Namely, the ability of video-derived CSIs to quantify the magnitude, accurate location, precise timing and rates of change associated with individual extreme events and seasonal variability in the wave climate. Secondly, video-derived coastal state indicators were used to monitor two different types of human intervention, including beach nourishments and a dredged pit in a navigation channel. The video-derived datasets of coastal state indicators offered significant improvement to current CZM practices, facilitating better timing of management interventions as well as more effective monitoring of the spatial impact and longevity of these actions.  相似文献   

2.
The fisheries sector is a significant contributor to the Egyptian economy. Recently, issues relating to fishing ports have been highlighted in port planning, availability of facilities, management, and environmental issues. Additional problems include Egypt's lack of specific guidelines for planning and design of fishing ports. This paper aims to assess the current status of five fishing ports (both natural and artificial) located along the Mediterranean coast of Egypt. Data were collected via a questionnaire supplied directly to the fishermen. The questionnaire contains two sections that cover information regarding the fishermen and fishing vessels. There are sections to assess the degree of satisfaction of the fishermen regarding economic, environmental, planning, facilities, and managerial issues. 250 fishermen received the questionnaire. The data were analyzed quantitatively and qualitatively. The results confirm that the fishing ports are negatively affected by a number issues, as well as management deficiencies, resulting in several weaknesses. The main issues include pollution, sedimentation, deterioration of infrastructure, and lack of port facilities. It is recommended that decision-makers should develop monitoring tools and improve infrastructure and services. Recommendations are made for future development to enable the expansion in the fishing industry and improve the sustainability of fishing ports.  相似文献   

3.
《Coastal Engineering》2007,54(6-7):567-576
This contribution provides a critical review of the CoastView project; a research program designed to develop and quantify video-derived Coastal State Indicators (CSIs) which simplify various aspects of coastal zone management including, coastal protection, navigation and recreation. This paper aims to provide a guide to future applied research projects of this kind. The research program implemented a ‘frame of reference’ methodology in order to effectively match research outcomes to the needs of end users and to facilitate communication within a consortium comprising both scientists and end users of the technology. Data derived from coastal video systems played a crucial role in defining CSIs which form a central component of the ‘frame of reference’ process. In general coastal video systems were demonstrated to be a very effective coastal management tool in all of the areas under investigation, uniquely providing data with excellent spatial and temporal resolution and coverage. Additionally, the ‘frame of reference’ ensured the appropriate match of science to the needs of the end user. However, even given these significant advances, the transfer of useful methodologies to applied tools is not guaranteed. The importance of providing simple, robust tools for delivering CSIs simply and efficiently to the coastal manager at the appropriate time-scale was recognised; ideally this should be completed within the timeframe of the research program. The acceptance of new methodologies is greatly enhanced by demonstrating them alongside more established techniques and other data sources, clearly showing the advantages, reliability and accuracy of the new approach.  相似文献   

4.
《Coastal Engineering》2007,54(6-7):507-521
This contribution proposes Coastal State Indicators (CSIs) for application to different aspects of recreational beach management. The beaches considered in this study are important leisure and tourism resources and of primary concern to the managers responsible is the recreational carrying capacity of the beach. Given the range of factors which potentially affect the carrying capacity this contribution is restricted to just two variables: the level of beach-use and safety. For each variable a detailed management framework is proposed together with a specific methodology to monitor appropriate CSIs. In all the cases, the proposed indicators make use of the capabilities of Argus video-cameras to record multi-purpose information in a single image. Specific algorithms are developed to deliver video-derived variables which are combined with supplementary data (e.g. wave and tide information) to yield beach management CSIs. The application of these CSIs is illustrated via two case studies.  相似文献   

5.
《Marine Policy》1999,23(4-5):413-425
Recent legislation aimed specifically at protecting the marine environment has had a direct impact on the environmental management of port and harbour operations. Effective implementation of suitable policies requires options and responses based on scientific data derived from appropriate technology and methodology. UK ports, operating under an increasingly European regime in terms of legislation, have responded to the environmental challenge through a series of organisational and research initiatives. Fundamental to the notion of sustainable port development is the ability to characterise environmental performance through appropriate monitoring and mapping protocols. Monitoring, the systematic and repeated measurement of the direct or indirect effect of our activity or contaminant on the environment, can play a crucial role in verifying implementation of port policy and evaluating the effectiveness of the management option. Aspects such as adherence to specific regulatory standards, investigation of pollution trends, provision of research data, measurements for the development of standards and early warning of critical changes in certain parameters are all facilitated by an appropriate monitoring protocol. The long established techniques of monitoring physical and chemical parameters to assess environmental quality are increasingly being supplemented by ecological monitoring programmes. By mapping marine habitats with their associated communities and species, the vulnerability and sensitivity of the habitats to port operations can be found and biological indicators such as the occurrence of particular species, species richness and diversity indices can be identified to assist decision making on environmental protection issues.  相似文献   

6.
7.
河口涨潮槽的研究进展   总被引:3,自引:0,他引:3  
河口涨潮槽是河口的重要地貌单元。对河口涨潮槽的发育过程与演化规律的研究在理论上可以丰富河口动力地貌的内容,而在实践上对港口和通航等具有重要的意义。文章认为河口涨潮槽不仅指河口涨潮流作用下形成的冲刷槽,还包括涨潮冲刷坑、涨潮冲刷槽和涨湖水道。国内外关于河口涨潮槽研究较为薄弱,研究内容多集中于涨潮槽的几何形态、涨落槽优势流判别和悬沙输移等方面,定性研究较多,缺乏全面而系统的定量研究,尤其缺乏成因机制方面的深入研究和沉积环境的研究。长江口涨潮槽种类较多,具有一定的研究基础,对其进行系统全面的研究具有重要的意义。  相似文献   

8.
To establish viable earthquake counterplans for ports in Korea, data regarding earthquake motion on the ground and in buildings must be collected using acceleration monitoring systems. Acceleration monitoring-based strategies for port facilities are useful not only for ensuring rapid responses during and after earthquakes but also for regional data collection to assist reliable seismic design. Acceleration monitoring systems were installed at coastal facility sites in target ports, including a soil site to represent the facility and a rock site as a reference. The systematic earthquake alert software was designed to help them in decision-making about a possible seismic hazard and its reporting. The earthquake alert system was composed of two sequential functional software systems sharing an acceleration monitoring database applied to the target ports. The earthquake response software system triggers an alarm based on the peak ground acceleration per second computed from the monitored data. Then, the earthquake hazard estimation software system evaluates possible earthquake-induced site-specific geotechnical hazards linked to the peak ground acceleration. The integrated system was successfully operated and was able to rapidly provide an emergency report containing event records and geotechnical earthquake hazards during the September 2016 Gyeongju earthquake, the largest recorded earthquake in Korea.  相似文献   

9.
A series of port constructions and large-scale reclamation projects have been extensively carried out in Quanzhou Bay to pursue social and economic benefits. These projects have changed the natural topographical and morphological evolution since 1970. In this research, from comparison of topographical and morphological characteristics of the study area in 2008, 1972 and 1934, the obvious differences between two evolution stages (1934-1972 and 1972-2008) were analyzed, and the impact of coastal engineering constructions on the evolution of topography and morphology was evaluated quantitatively. The results show that evolution before the 1970s was characterized as a stable whole with local erosion in the channel and slow aggradation of the shoal and that the morphology was dominated by natural processes, as there was little coastal engineering construction before 1970. Since the 1970s, because of a series of engineering projects such as those reclaiming land and constructing ports, the bay has been in a stage of continuous silting, characterized by the channel narrowing and shrinking and shoal silting and expanding, which may result in the abandonment of ports around the bay and endanger the salt field, aquaculture and other agriculture. Potential solutions for the management of the coastal zone of Quanzhou Bay and other similar bays by state and local agencies are suggested, such as calling for the attention of the state and local government, strengthening coastal zone management, scientific planning and reasonable exploitation, and in particular, changing the utilization of the sea area.  相似文献   

10.
-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.  相似文献   

11.
为充分发挥粤港澳大湾区港口的竞争优势,促进港口经济的协调发展,文章基于粤港澳大湾区主要港口的实际情况,构建供应链博弈模型并进行数值仿真,研究相关因素对深圳港和香港港绩效的影响。研究结果表明:随着商品价格和库存成本的提高,货物从深圳港向香港港转移,但转移幅度逐渐趋缓;深圳港在中低端商品的货源收集方面具有明显的竞争优势,而香港港对高端商品的吸引力更强;货运结构逐渐向中高端商品过渡对于提高港口收益具有促进作用,其中深圳港应通过降低商品库存成本而降低经营风险;深中通道和港珠澳大桥通车有效缩短腹地运输时间,对于绝大部分商品价格和库存成本组合都将提高粤港澳大湾区港口的总收益。  相似文献   

12.
《Marine Policy》2007,31(5):591-598
Cruise ships represent less than 1% of the global merchant fleet yet it has been estimated that they are responsible for 25% of all waste generated by merchant vessels. This volume of waste produces pressures on the environment, particularly with respect to ship-generated waste disposal at home ports and ports of call. Southampton, home port for both Cunard and P&O, and a port of call for Royal Caribbean Cruises, is the focus of this study. This paper investigates current waste management and disposal options for cruise ship generated waste and the associated impacts of this waste for ports. It is concluded that all cruise vessels should vigorously pursue a waste reduction strategy and for ports to provide adequate recycling, reduction and re-use facilities for cruise ship generated waste, optimising use of local facilities whenever possible.  相似文献   

13.
Spatial diversity equalization applied to underwater communications   总被引:1,自引:0,他引:1  
Underwater acoustic digital communication is difficult because of the nature of the fading multipath channels. Digital signal processing, such as adaptive equalization, is known to greatly improve the communication data rate by limiting intersymbol interference (ISI). However, existing underwater acoustic equalization studies are limited to single-channel techniques, and spatial diversity processing is limited to selection or combining. In this paper, we design minimum mean-square error (MMSE) equalizers jointly among all spatial diversity channels. We call this spatial diversity equalization (SDE). Results are based on a very sparse vertical array in a midrange underwater acoustic channel. We study the effect of element number and placement, the length of the equalization filters, and linear feedforward versus nonlinear decision feedback algorithms. A suboptimum equalizer combiner (EC) is studied to alleviate the computational intensity of JCE. We first design the system for a known acoustic channel; later, some results are verified using adaptive algorithms. Results are presented both in terms of the mean-square error (MSE) and the probability of a symbol error. The latter is important as it is the ultimate interest for a digital communication system. We found that system performance improves rapidly with an increase in the number of spatial channels  相似文献   

14.
- This paper, after briefly reviewing the experimental research on sediment transport on muddy beach since the 1950s, improves and perfects the method for forecasting siltation in navigation channels and harbour basins which was first put forward in China by the authors. In consideration of silty sediment and sand, some factors in forecasting methods have been changed and modified. Consequently, the modified methods can be used either to compute siltation in navigation channels and harbour basins on muddy beach or to compute siltation and scouring in navigation channels and harbour basins on both silty beach and sandy beach. The verification of field data from eleven large, medium and small natural harbours shows a good agreement between the forecasting by the modified method and the natural conditions. Finally, the paper deals with the rational utilization of water area after the construction of the West Dyke in Lianyungang, the maintenance of water depth of the navigation channel at the entrance, siltation distribution, siltation in the navigation channel and harbour basin for ships of 100 thousand tonnnage. Results once again prove that the prospect of constructing Lianyungang Harbour into a deepwater harbour is bright.  相似文献   

15.
海南省拟建琼州海峡铁路轮渡。本文通过对海峡南岸新海湾轮渡港址附近自然条件、岸滩演变和输沙特征的分析研究,对不同类型港区布置方案港内开挖区和航道的淤积强度、淤积量等进行了计算,并对不同防护建筑物的有效拦沙时间等进行了探讨和计算,提出了港区类型推荐方案。  相似文献   

16.
通过实地调研,结合历史记录资料,初步研究了风暴潮对广东省沿海港航设施的影响状况和特点,提出了相应的防护措施。研究发现,广东省沿海港口设施受风暴潮影响的主要特点为防波堤受损最为严重,施工期受风暴潮影响损坏普遍存在,码头护岸受损较普遍,大型码头结构受损较少,中、小型码头结构特别是渔港结构受损较多。损坏成因主要包括波浪基础资料不足、设计波浪偏低、护面块体偏小等。从技术、工程和管理三个方面提出了防护措施。技术措施主要为加强波浪观测和科学研究;改进设计波浪推算方法。工程措施包括适当提高设计波浪标准;适当提高护面块体标准;优化平面布置,缩短无防护施工期;设立安全岛和避险安全区;加强对已建港航设施的现状调查、复核和分析,采取针对性的加固措施等。管理措施包括设立沿海港口风暴潮预警预报系统;编制风暴潮应急预案;加强港航设施的维护等。  相似文献   

17.
The Tianjin Port is the largest man-made port in China.Since the navigation channel of the Tianjin Port is constructed by dredging,a very important problem,as many people concerned,is the submarine slope stability.As the environment on land is different from that in submarine,it is necessary to evaluate the influence of the environmental loading,such as wave and tide,on the stability of navigation channel slope.In the present study,based on the observed results,the characteristics of the navigation channel slope are summarized,and the causes of creating the special slope shape are analyzed.The roles of waves and tides are evaluated,and failure mechanics are discussed to helq us predict what will happen in the future.  相似文献   

18.
《Marine Policy》1999,23(4-5):307-327
The ability to comply fully with the discharge requirements set out in the MARPOL 73/78 Convention depends upon the availability of adequate facilities on land for the reception of shipgenerated waste. This paper considers ways of ensuring adequate provision of reception facilities, and discusses the approach taken by the UK to reduce the amount of pollution entering the marine environment from the deliberate discharge of waste from ships. Arguably, the most significant of the measures adopted by the UK is the requirement for all ports and harbours to prepare port waste management plans. Disincentives to the use of port waste reception facilities are examined, together with the benefits and shortcomings of various financing arrangements, and compulsory discharge of waste in ports. The paper concludes that the statutory approach to improving the provision and use of waste facilities should be supported by an appropriate awareness campaign to educate shipowners about the need to discharge waste legally to port reception facilities.  相似文献   

19.
北部湾茅尾海是中国南方重要的经济开发区,兴建有滨海新城和多个港口码头,近年来围垦开发严重。本研究通过建立二维水动力数值模型系统,分析重要潮汐动力参数,对比研究1985年与2020年间钦州湾围垦和港口建设对当地水动力环境的影响。结果表明:经过围填海和港口工程之后,茅尾海的潮差变化较小,略微增加了0.05 m左右;全日分潮K1、O1及半日分潮M2、S2是影响钦州湾潮汐动力较大的驱动力,围垦后在茅尾海内海地区都略微增加了0.02~0.03 m,其中K1、O1是影响茅尾海的关键潮汐动力参数,敏感性测试分析表明三墩公路建设、钦州港海岸围垦和核电厂导堤建设对茅尾海潮差增加贡献率大致占60%、20%和10%;同时,围垦对束窄钦州湾航道具有一定的优化效应,围垦后钦州湾外湾三条水道峰值通量都明显增加,形成航道束水攻沙效果,对通航和维护主航道稳定性具有一定优势。因此,仅从潮汐动力参数变化角度分析,目前的围垦和港口工程迎合了当地河势特征,对潮汐动力场扰动较小,具有优化局部水动力场环境和提升通航安全性作用。  相似文献   

20.
钱塘江河口段通航能力的初步分析   总被引:1,自引:0,他引:1  
本文阐述了钱塘江通海航道的现状,指出仓前至尖山的中段航道影响着河口出海通航能力,四工段浅滩是主要的碍航浅滩。文中还对不同水文条件下,钱塘江河口段的乘潮保证率和最大可能出海运量作了分析,在此基础上提出了改善航道条件的措施。  相似文献   

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