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生态环境保护中基层环境监测管理的问题探讨
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作者 沈丽 《中国科技期刊数据库 工业A》 2024年第10期0030-0033,共4页
在当前我国的经济增长中,生态环监已成为生态环保领域所重点关注的议题。深入研究相关的技术并促进其进步,有助于更加有效地实现环境保护目标。环保机构在这方面应当给予高度关注,明确环境监控工作的重要性,并采纳相关实施措施,以确保... 在当前我国的经济增长中,生态环监已成为生态环保领域所重点关注的议题。深入研究相关的技术并促进其进步,有助于更加有效地实现环境保护目标。环保机构在这方面应当给予高度关注,明确环境监控工作的重要性,并采纳相关实施措施,以确保环监数据信息的准确性。本文以生态环境监控技术作为主要研究对象,对常见的环境监控技术手段进行了详细解释,详细描述了生态环境监测的工作流程,并探讨了其在环境保护工作中所起到的重要作用和价值,目的是为我国在环保领域的进一步发展贡献更强大的力量。 展开更多
关键词 生态环境保护 基层环境监测管理 干问题
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三峡库区带有干中学的跨界污染问题研究 被引量:1
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作者 鲁祖亮 李林 黄飞 《湘潭大学学报(自然科学版)》 CAS 2019年第1期72-81,共10页
主要考虑了一类三峡库区跨界污染问题,其排放权交易与减排成本是基于干中学理论,减排成本主要依赖于使用减排技术的经验和减排水平.对于合作型与非合作型跨界污染问题,利用最优控制理论研究了该模型的最优排放路径与最优污染减排策略.最... 主要考虑了一类三峡库区跨界污染问题,其排放权交易与减排成本是基于干中学理论,减排成本主要依赖于使用减排技术的经验和减排水平.对于合作型与非合作型跨界污染问题,利用最优控制理论研究了该模型的最优排放路径与最优污染减排策略.最后,针对重庆和湖北的实际经济数据,采用龙格-库塔方法求解了非合作型与合作型跨界污染问题的减排水平和污染库存,并分析了两个区域积累经验能力差异的改变对模型的影响. 展开更多
关键词 带有中学的跨界污染问题 三峡库区 最优控制理论 龙格-库塔方法
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市政污泥干化过程中能量梯级利用设想与热力计算
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作者 陈凯锋 骆律源 《华东科技(综合)》 2019年第7期408-408,430,共2页
随着国家污水处理设施不断完善,污水处理率逐年提高,处理程度逐渐深化,污泥处理量越来越多,污泥处置压力日益增大,成为城市污水处理行业的瓶颈。近年来,随着各地生活垃圾填埋场的陆续封场、或转变用途,市政污泥去向问题更加突出。
关键词 问题 废热利用方式
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ALC轻质隔墙板裂缝防治施工技术研究
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作者 晁静 《现代物业(中旬刊)》 2023年第8期166-168,共3页
轻质隔墙板在实践应用中具有自重轻、耐受力强,防水隔音效果好几方面优势。作为板材结构轻质隔墙板,在实践应用中会出现典型裂缝问题。针对ALC轻质隔墙板裂缝问题进行研究,并进一步提出防治施工技术措施,有利于提高ALC轻质隔墙板应用质... 轻质隔墙板在实践应用中具有自重轻、耐受力强,防水隔音效果好几方面优势。作为板材结构轻质隔墙板,在实践应用中会出现典型裂缝问题。针对ALC轻质隔墙板裂缝问题进行研究,并进一步提出防治施工技术措施,有利于提高ALC轻质隔墙板应用质量,降低裂缝问题发生率。通过本文实践分析可知,ALC轻质隔墙板产生裂缝的主要原因包括轻质隔墙板材料质量因素、施工工艺因素、隔墙板干缩率因素、隔墙板养护因素。需在裂缝防治环节通过加强原材料筛选合理性、有效优化施工工艺流程、做好ALC轻质隔墙板细部处理工作、重视轻质隔墙板养护工作。达到有效防治裂缝这一目标。 展开更多
关键词 ALC轻质隔墙板 裂缝防治 问题 养护工作
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ALC轻质隔墙板裂缝防治施工技术研究
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作者 赵思雨 《中文科技期刊数据库(全文版)工程技术》 2023年第11期97-100,共4页
轻质隔墙板在实践应用中具有自重轻、耐受力强,防水隔音效果好几方面优势。作为板材结构轻质隔墙板,在实践应用中会出现典型裂缝问题。针对ALC轻质隔墙板裂缝问题进行研究,并进一步提出防治施工技术措施,有利于提高ALC轻质隔墙板应用质... 轻质隔墙板在实践应用中具有自重轻、耐受力强,防水隔音效果好几方面优势。作为板材结构轻质隔墙板,在实践应用中会出现典型裂缝问题。针对ALC轻质隔墙板裂缝问题进行研究,并进一步提出防治施工技术措施,有利于提高ALC轻质隔墙板应用质量,降低裂缝问题发生率。通过本文实践分析可知,ALC轻质隔墙板产生裂缝的主要原因包括轻质隔墙板材料质量因素、施工工艺因素、隔墙板干缩率因素、隔墙板养护因素。需在裂缝防治环节通过加强原材料筛选合理性、有效优化施工工艺流程、做好ALC轻质隔墙板细部处理工作、重视轻质隔墙板养护工作。达到有效防治裂缝这一目标。 展开更多
关键词 ALC轻质隔墙板 裂缝防治 问题 养护工作
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一类推广的干摩擦问题周期解的存在性
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作者 柴彦红 邵晶 曹雪梅 《数学的实践与认识》 CSCD 北大核心 2011年第21期220-226,共7页
为了得到干摩擦问题存在周期解的判断方法,利用微分包含理论对系统+k^2x+μSngp(t)+T(t)a.e.进行了讨论.在周期外力p(t)周期等于固有周期2π/R的情形下得到了周期解存在的充要条件,在周期外力p(t)周期不等于固有周期整数倍2nπ/R的... 为了得到干摩擦问题存在周期解的判断方法,利用微分包含理论对系统+k^2x+μSngp(t)+T(t)a.e.进行了讨论.在周期外力p(t)周期等于固有周期2π/R的情形下得到了周期解存在的充要条件,在周期外力p(t)周期不等于固有周期整数倍2nπ/R的情形下得到了周期解存在的充分条件. 展开更多
关键词 摩擦问题 周期解 存在性
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LTE-A异构网络中新的用户选择接入和资源分配联合方法 被引量:3
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作者 姜来为 沙学军 +1 位作者 吴宣利 张乃通 《吉林大学学报(工学版)》 EI CAS CSCD 北大核心 2017年第6期1926-1932,共7页
将信干噪比估计不确定问题引入到有几乎空白子帧存在时的异构网络中,在异构网络中提出一种新的用户选择接入和资源分配联合算法。为了用最少的无线资源满足用户的传输速率需求,将问题建模为最小-最大差值广义分配模型,然后进行求解。仿... 将信干噪比估计不确定问题引入到有几乎空白子帧存在时的异构网络中,在异构网络中提出一种新的用户选择接入和资源分配联合算法。为了用最少的无线资源满足用户的传输速率需求,将问题建模为最小-最大差值广义分配模型,然后进行求解。仿真结果验证了本文方法的可行性。 展开更多
关键词 通信技术 LTE-A异构网络 噪比估计不确定问题 用户选择接入 资源分配 最小-最大差值广义分配
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Underdetermined Blind Source Separation of Adjacent Satellite Interference Based on Sparseness 被引量:10
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作者 Chengjie Li Lidong Zhu Zhongqiang Luo 《China Communications》 SCIE CSCD 2017年第4期140-149,共10页
The problem of underdetermined blind source separation of adjacent satellite interference is proposed in this paper. Density Clustering algorithm(DC-algorithm) presented in this article is different from traditional m... The problem of underdetermined blind source separation of adjacent satellite interference is proposed in this paper. Density Clustering algorithm(DC-algorithm) presented in this article is different from traditional methods. Sparseness representation has been applied in underdetermined blind signal source separation. However, some difficulties have not been considered, such as the number of sources is unknown or the mixed matrix is ill-conditioned. In order to find out the number of the mixed signals, Short Time Fourier Transform(STFT) is employed to segment received mixtures. Then, we formulate the blind source signal as cluster problem. Furthermore, we construct Cost Function Pair and Decision Coordinate System by using density clustering. At the end of this paper, we discuss the performance of the proposed method and verify the novel method based on several simulations. We verify the proposed method on numerical experiments with real signal transmission, which demonstrates the validity of the proposed method. 展开更多
关键词 adjacent satellite interference Short Time Fourier Transform Decision Coordinate System real signal transmission
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Indoor measurement method of smoke screen disturbance efficiency based on Gaussian diffusion model 被引量:1
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作者 曹营军 冯武斌 +1 位作者 李杏军 郝文波 《Journal of Measurement Science and Instrumentation》 CAS 2013年第2期116-118,共3页
Because of ground clutter wave interf e rence,it is difficult to measure smoke screen disturbance in the field.In this pape r,a kind of indoor measurement method of smoke screen disturbance efficiency ba sed on Gaussi... Because of ground clutter wave interf e rence,it is difficult to measure smoke screen disturbance in the field.In this pape r,a kind of indoor measurement method of smoke screen disturbance efficiency ba sed on Gaussian diffusion model is put forward.As a characteristic,the measur ement result of smoke screen area density proves that the indoor measurement met hod of smoke screen disturbance efficiency based on Gaussian diffusion model is fea sible. 展开更多
关键词 smoke screen disturbance efficiency Gaussian diffusion model indoor measurement
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BCS Ground State and XXZ Antiferromagnetic Model as SU(2),SU(1,1) Coherent States:AN Algebraic Diagonalization Method 被引量:2
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作者 XIEBing_Hao ZHANGHong-Biao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第3期292-296,共5页
An algebraic diagonalization method is proposed. As two examples, the Hamiltonians of BCS ground stateunder mean-field approximation and XXZ antiferromagnetic model in linear spin-wave frame have been diagonalized byu... An algebraic diagonalization method is proposed. As two examples, the Hamiltonians of BCS ground stateunder mean-field approximation and XXZ antiferromagnetic model in linear spin-wave frame have been diagonalized byusing SU(2), SU(1,1) Lie algebraic method, respectively. Meanwhile, the eigenstates of the above two models are revealedto be SU(2), SU(1,1) coherent states, respectively. The relation between the usual Bogoliubov Valatin transformationand the algebraic method in a special case is also discussed. 展开更多
关键词 algebraic diagonalization method coherent state
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Resource and Environmental Issues in Transitional China:A Perspective from the Interaction Among Market,Government and Society 被引量:1
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作者 Zhao Haixia Qu Futian +1 位作者 Zhu Peixin Shi Xiaoping 《Chinese Journal of Population,Resources and Environment》 2010年第2期13-23,共11页
Along with the rapid growth of economy in the postreform period after 1979,China has faced severe problems of resource overusing and environmental degradation which would threaten the sustainable development of econom... Along with the rapid growth of economy in the postreform period after 1979,China has faced severe problems of resource overusing and environmental degradation which would threaten the sustainable development of economy and society.This article explores an effective mechanism of managing resource and environment in China.It examines some major resource and environmental issues,and constructs a framework of institution innovation to cover three sectors(government,market and society) . In addition,the article analyzes their experience and evaluation in resource management and environmental conservation during the transitional period.We argue that the combination of market regulation,government intervention and public participation is an effective way of allocating resource and protecting environment. Some suggestions are put forward to balance the relationship between them,including coordinating role of government and market,building platform for market operation and creating an atmosphere of public participation. 展开更多
关键词 economic transition resource and environment management institution innovation triangle balance
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Dynamical Correction of Control Laws for Marine Ships’ Accurate Steering 被引量:1
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作者 Evgeny I. Veremey 《Journal of Marine Science and Application》 2014年第2期127-133,共7页
The objective of this work is the analytical synthesis problem for marine vehicles autopilots design. Despite numerous known methods for a solution, the mentioned problem is very complicated due to the presence of an ... The objective of this work is the analytical synthesis problem for marine vehicles autopilots design. Despite numerous known methods for a solution, the mentioned problem is very complicated due to the presence of an extensive population of certain dynamical conditions, requirements and restrictions, which must be satisfied by the appropriate choice of a steering control law. The aim of this paper is to simplify the procedure of the synthesis, providing accurate steering with desirable dynamics of the control system. The approach proposed here is based on the usage of a special unified multipurpose control law structure that allows decoupling a synthesis into simpler particular optimization problems. In particular, this structure includes a dynamical corrector to support the desirable features for the vehicle's motion under the action of sea wave disturbances. As a result, a specialized new method for the corrector design is proposed to provide an accurate steering or a trade-off between accurate steering and economical steering of the ship. This method guaranties a certain flexibility of the control law with respect to an actual environment of the sailing;its corresponding turning can be realized in real time onboard. 展开更多
关键词 marine ships control law dynamical corrector accurate steering autopilot sea wave
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Study of IMT-advanced heterogeneous network
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作者 Qin Fei Peng Ying Sun Shaohui Wang Yingmin 《Engineering Sciences》 EI 2011年第4期27-31,共5页
Referring to research on the Heterogeneous Network (Het-Net) application scenario and technique characters in IMT-Advaneed (The 4th Generation Mobile Communications) cellular system, this paper provides further an... Referring to research on the Heterogeneous Network (Het-Net) application scenario and technique characters in IMT-Advaneed (The 4th Generation Mobile Communications) cellular system, this paper provides further analysis on main technique aspects of Heterogeneous Network, discussion on interference issue due to multi-layer building by access points and their corresponding solutions from standardization and engineering implementation. The proposed solution can effectively solve the interference problem in IMT-advanced Het-Net, and also improves the networking performance dramaticaUy for future mobile communication systems. 展开更多
关键词 HETEROGENEOUS HIERARCHICAL home NodeB home eNodeB network deployment IMT-advaneed FEMTO
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《中国西北气候由暖干向暖湿转型问题评估》出版 被引量:1
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作者 王亚俊 《干旱区研究》 CSCD 2003年第2期147-147,共1页
关键词 《中国西北气候由暖向暖湿转型问题评估》 书评 气候变化 施雅风 中国科学院知识创新工程
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Machine Interference Problem with Reliable Server under Single Vacation
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作者 Ojobor, S. A. 《Journal of Mathematics and System Science》 2014年第11期732-742,共11页
The machine interference problem with reliable server under single vacation is considered here. There are M similar machines that are subject to fail or breaks down with a single server who is responsible for repairin... The machine interference problem with reliable server under single vacation is considered here. There are M similar machines that are subject to fail or breaks down with a single server who is responsible for repairing or maintaining the failed machines. The machine fails completely at random with rate 2 and they are serviced in order of breaks down. More so, the machines operate independently but are subject to fail or break down. The service time distributions of the failed machines are assumed to be exponentially distributed with state dependent service rate #n, where n is the number of failed machines. By state dependent service rate we mean a situation where the rate of service depends on the number of failed machines present in the system. The Chapman-Kolmogorov differential equations obtained for the reliable server under single vacation model is solved through ODE45 (Runge-Kutta algorithm of order 4 and 5) in MATLAB programming language. The transient probabilities obtained are used to compute the operational measures of performance for the systems. The following time dependent operational measures of performance for the system are obtained: expected number of failed machines, expected number of operating machines, machine availability, expected idle period, expected busy period, operational utilization of the machine, the variance of the expected number of failed machine and variance of expected number of operating machine in the system. The effects of failure rate of machines, service rate of failed machines and the number of operating machines are investigated; it is observe that the rate at which machine fails and is serviced, affect the expected number of failed and operating machines in the system. The CPU time for obtaining the transient results for the systems and the variance of the systems are reported in this work. 展开更多
关键词 Transient solution machine interference problem Reliable server Single vacation ODE45 in MATLAB.
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浙江省与“一带一路”沿线国家贸易现状及发展思路研究
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作者 杨建国 《产业创新研究》 2018年第2期27-31,共5页
"一带一路"是中国特色社会主义新时代进一步深化开放的重大战略部署。浙江省现阶段处于工业化中后期,而"一带一路"沿线国家处于不同的工业化阶段,形成了不同的优势产业类型,浙江与"一带一路"沿线国家贸... "一带一路"是中国特色社会主义新时代进一步深化开放的重大战略部署。浙江省现阶段处于工业化中后期,而"一带一路"沿线国家处于不同的工业化阶段,形成了不同的优势产业类型,浙江与"一带一路"沿线国家贸易潜力巨大。本文选取越南、印度尼西亚、泰国、沙特阿拉伯、伊朗、南非6个国家作为分析样本,采集杭州海关与上述国家进出口数据,进行产业内贸易指数计算,并对机电、纺织、化工三大重点行业国际贸易情况进行分析,最后对浙江与"一带一路"沿线国家外贸发展提出建议。总体发展思路是,针对"一带一路"沿线国家不同的产业梯度及其与浙江省产业不同的竞争状态,对于产业内贸易指数高的行业,应着重产品差别化,对产业内贸易指数较低、互补性强的行业,则应着眼于利用"一带一路"带来的战略机遇,大力拓展新兴国家市场。 展开更多
关键词 “一带一路” 产业内贸易 差异化
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Mental health service to military retired cadres
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作者 Liang Wei Wu Qing Dai Jiuchun 《Journal of Medical Colleges of PLA(China)》 CAS 2012年第6期368-372,共5页
Military retired cadres were commonly in aged period with high-incidence of diseases. They were troubled with senility, illness, empty-nest syndrome and spouse-bereft, so they were more vulnerable to some psychologica... Military retired cadres were commonly in aged period with high-incidence of diseases. They were troubled with senility, illness, empty-nest syndrome and spouse-bereft, so they were more vulnerable to some psychological problems. Therefore, promoting the mental health service for retired cadres should be highly concerned and more professional service work should be provided to them. 展开更多
关键词 Mental health Health care MILITARY Retired cadres
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Neighbour Peer Selection Scheme Based on Effective Capacity for Mobile Peer-to-Peer Streaming
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作者 夏海轮 王宁 曾志民 《China Communications》 SCIE CSCD 2013年第5期89-98,共10页
For Peer-to-Peer (P2P) streaming services in mobile networks, the selection of appropriate neighbour peers from candidate peers with demanding data is an important approach to improve Quality-of-Service (QoS). This pa... For Peer-to-Peer (P2P) streaming services in mobile networks, the selection of appropriate neighbour peers from candidate peers with demanding data is an important approach to improve Quality-of-Service (QoS). This paper proposes a novel Effective Capacity Peer Selection (ECPS) scheme based on effective capacity. In the ECPS scheme, the neighbour peer selection problem was modeled using the Multiple Attribute Decision Making (MADM) theory, which considered multiple factors of candidate peers, including Signal to Interference and Noise Ratio (SINR), residency time, power level, security, moving speed, and effective capacity. This model could increase the suitability of ECPS for wireless mobile environments. Then, the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) was used to solve the MADM problem and identify the preferred neighbour peers. Simulation results show that the ECPS scheme can improve the network throughput, reduce packet delay by about 82%, and almost double the packet delivery ratio of the mobile P2P streaming service. 展开更多
关键词 P2P mobile P2P streaming peer selection effective capacity MADM QoS
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Evaluation of the Collapsibility of Soils in the Semiarid Region of Pernambuco, Brazil 被引量:1
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作者 Silvio Romero de Melo Ferreira Stela Fucale 《Journal of Civil Engineering and Architecture》 2014年第10期1285-1292,共8页
Some unsaturated soils may undergo volumetric changes when submitted to an increase in its water content or are inundated under applied loads. This behavior is related to the volumetric instability when the water cont... Some unsaturated soils may undergo volumetric changes when submitted to an increase in its water content or are inundated under applied loads. This behavior is related to the volumetric instability when the water content is changed. Natural collapsible soils in Brazil are generally found in alluvial, colluvial and residual soils. There are known occurrences of natural collapsible soils in many states of Brasil. In the last two decades, many public projects have been developed in areas where the occurrence of collapsible soils has been associated to geotechnical problems. The present paper devoted to study the collapsible soils in the state of Pernambuco which has been associated with large engineering projects such as housing and irrigation canals. The geotechnical investigation program included test with a field apparatus, called Expanso-colapsometer, which allows the measurement of the field settlements of a small 0.10 m of diameter plate inserted at any depth inside an auger boring hole. Reconnaissance borings with SPT (standard penetration test), investigation pits with undisturbed block sampling and disturbed samples for laboratory tests were also made in order to assess the type and characteristics of the soil. Field tests used the Expanso-colapsometer to measure the settlement of the soil in selected depths under controlled flooding. Laboratory work included double and standard oedometer tests with a controlled rate of water inflow of 1.0 mL/s. It was found that the volume change of the soils when flooded depends on their natural stress state (vertical stress, suction head and structure of soil). 展开更多
关键词 Collapsible soils field tests laboratory tests.
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PIV Studies on Turbulence Structure in Air/Water Interface with Wind-Induced Water Waves
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作者 M. Sanjou, I. Nezu A. Toda 《Journal of Energy and Power Engineering》 2011年第11期1063-1067,共5页
When wind appears over the free surface, water waves and turbulence are generated by an interfacial shear stress. In particular, turbulent diffusion promotes significantly mass and momentum transport beneath the inter... When wind appears over the free surface, water waves and turbulence are generated by an interfacial shear stress. In particular, turbulent diffusion promotes significantly mass and momentum transport beneath the interface between the water and air significantly in ocean and lakes, and thus it is very important for global environment problems to reveal such turbulence property and coherent structure. Simultaneous measurements of velocities and free-surface elevation allow us to conduct reasonably the phase analysis of the coherent structure in interfacial shear layer. Furthermore, multi-point measurements such as PIV are very powerful to detect the space-time structure of coherent motions. Therefore, in the present study, we developed a specially designed PIV system which can measure the velocity components and surface-elevation fluctuation simultaneously by using two sets of high-speed cameras to reveal the coherent structure in the interfacial shear layer. 展开更多
关键词 Air/water interface wind-induced water waves PIV measurements.
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