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作者： Imran Aziz 哈尔滨工程大学

学位级别：硕士

The green water problem has been known in the maritime world for a long time. Although there are much advanced experimental facilities available throughout the world in the form of towing tanks. But since it is expensive to carry out model tests, a reliable and efficient numerical tool for green water prediction is always needed.Thus present work aims at developing a numerical method that can predict the green water loads on ships and offshore structures. The work was divided into two main parts. At first the relative wave elevation was calculated taking into account all the factors that have there influence on relative wave motion. The importance of radiation and diffraction waves in overall wave elevation has also been explained in detail and results have been compared for various wave headings and positions along the surface of a cylinder and ship models. The results were calculated for a fixed cylinder, an FPSO model and an S-175 ship model. Hydrostar was used to predict the sea keeping characteristics for ship models in frequency domain at zero forward speed, later these results were transformed into time domain calculation of the said parameters.In the second part of the research work, the water flow onto the deck and the resulting loads on ship's deck and deck structure were calculated. Once the relative wave elevation and the freeboard exceedance were known, Dam break flow was used to calculate the resulting water heights and velocities at certain point on deck. The freeboard exceedance is taking as a time dependant variable for more realistic results. In order to cater for the water that is reflected back from the structure, a reverse dam flow method was introduced, the comparison of reverse dam flow results is also explained in detail. Finally the Newton's second law was used to formulate the expressions for vertical and horizontal loads on deck. The deck's vertical velocity and acceleration were also taken into account in load calculations. Th

关键词： green water relative wave motion radiation and diffraction reverse dam break flow CFX Swell up coefficient simulation freeboard exceedance Newton's formulation

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Effects of climate change and land-use changes on spatiotemporal distributions of blue water and green water in Ningxia, Northwest China

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Journal of Arid Land 2021年第7期13卷 674-687页

作者： WU Jun DENG Guoning ZHOU Dongmei ZHU Xiaoyan MA Jing CEN Guozhang JIN Yinli ZHANG Jun College of Resources and Environmental Science Gansu Agricultural UniversityLanzhou 730070China Research Center for water-saving Agriculture in Gansu Province Lanzhou 730070China Gansu Provincial Key Laboratory of Arid Land Crop Science Gansu Agricultural UniversityLanzhou 730070China

water resources are a crucial factor that determines the health of ecosystems and socio-economic development;however,they are under threat due to climate change and human *** quantitative assessment of water resources using the concept of blue water and green water can improve regional water resources *** this study,spatiotemporal distributions of blue water and green water were simulated and analyzed under scenarios of climate change and land-use changes using the Soil and water Assessment Tool(SWAT)in Ningxia Hui Autonomous Region,Northwest China,between 2009 and *** water,a leading component of water resources,accounted for more than 69.00%of the total water resources in *** water and green water showed a single peak trend on the monthly and annual scales during the study *** the spatial scale,the southern region of Ningxia showed higher blue water and green water resources than the northern *** spatiotemporal distribution features of blue water,green water,and green water flow had strong correlations with ***,the simulation identified the climate change in Ningxia to be more influential on blue water and green water than land-use *** study provides a specific scientific foundation to manage water resources in Ningxia when encountered with climate change together with human activities.

关键词： blue water green water climate change human activities SWAT semi-arid region

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强非线性规则波中内倾船的甲板上浪数值研究

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哈尔滨工程大学学报（英文版） 2023年第1期22卷 102-114页

作者：孙柏康赵彬彬徐杨马山段文洋 College of Shipbuilding Engineering Harbin Engineering UniversityHarbin 150001China School of Ocean Engineering and Technology Sun Yat-sen UniversityZhuhai 519082China

Owing to the large amplitude and nonlinearity of extreme sea waves,sailing ships exhibit obvious large-amplitude motion and green *** a tumblehome vessel,a low-tumblehome freeboard and wave-piercing bow make green water more *** study the green water of a wave-facing sailing tumblehome vessel in strong nonlinear regular waves,the computational fluid dynamics software STAR-CCM+was *** Reynolds-averaged Navier–Stokes method was used for the numerical simulation,and the k-epsilon model was adopted to deal with viscous *** volume of the fluid method was used to capture the free surface,and overset grids were utilized to simulate the large-amplitude ship *** study delves into the influence of wave height on the ship motion response and a tumblehome vessel green water under a large wave steepness(0.033≤H/λ≤0.067)at Fr=*** addition,the dynamic process of green water and the“wave run-up”phenomenon were *** results suggest that when the wavelength is equal to the ship length and the wave steepness increases to 0.056,the increase in the water height on the deck is ***,the wave height had little effect on the green water *** wave steepness and“backwater”have a great impact on the value and number of the peak of the water height on the *** the wave steepness exceeded 0.056,the water climbed up,and the plunging-type water body was formed at the top of the wave baffle,resulting in a large water area on the deck.

关键词： Tumblehome vessel green water Impact loads Wave run-up Strong nonlinear regular waves

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Effect of future climate change on the water footprint of major crops in southern Tajikistan

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Regional Sustainability 2021年第1期2卷 60-72页

作者： Muhammadjon Kobuliev Tie Liu Zainalobudin Kobuliev Xi Chen Aminjon Gulakhmadov Anming Bao State Key Laborutory of Desert and Oasis Xinjiang Instinite of Fcology and GeographyChinese Academy of Sciences Urmgi830011China University of Chinese Acadeny of Sciences Beijing 100049China Instinite of water Problems Hydropower and Rcology of the Academy of Sciences of the Repubic of Taikisan Dushanbe734042Tajikistan Research Center for Ecology and Emironment of Central Asia Chinese Acadmy of SciencesUrumqi830011China China-Pakistan Joint Research Center on Farth Sciences CAS-HECIslamabad 45320Pakistan

Danghara,a major food production area in southern Tajikistan,is currently suffering from the impact of rapid climate change and intensive human *** the future impact of climate change on crop water requirements(CWRs)for the current growing period and defining the optimal sowing date to reduce future crop water demand are essential for local/regional water and food ***,this study attempted to analyze possible future climate change effects on the water requirements of major crops using the statistical downscaling method in the Danghara District to simulate the future temperature and precipitation for two future periods(2021-2050 and 2051-2080),under three representative concentration pathways(RCP2.6,RCP4.5,and RCP8.5)according to the CanESM2 global climate *** water footprint(WFP)of major crops was calculated as a measure of their *** increased projection of precipitation and temperature probably caused an increase in the main crop’s WFP for the current growing period,which was mainly due to the green water(GW)component in the long term and a decrease in the blue water(BW)component during the second future period,except for cotton,where all components were predicted to remain *** three scenarios for the two future potato and winter wheat decreased from 5.7%to 4.8%and 3.4%to 2.2%,*** the WFP of cotton demonstrated a stable increase,according to the optimal sowing date,adecrease in irrigation demand or Bw was *** results of our study might be useful fordeveloping a new strategy related to irrigation systems and could help to find a balance betweenwater and food for environmental water demands and human use.

关键词： Optimal sowing date Representative concentration pathway Crop water requirement Statistical downscaling method green water Blue water Southern Tajikistan

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Environmental Sustainability of water Footprint in China' Mainland

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Geography and Sustainability 2020年第1期1卷 8-17页

作者： Junguo Liu Dandan Zhao Ganquan Mao Wenhui Cui He Chena Hong Yang School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen 518055China water&Development Research Group Department of Built EnvironmentAalto UniversityPO Box 15200Espoo 00076Finland Department of Systems Analysis Integrated Assessment and ModellingSwiss Federal Institute for Aquatic Science and Technology(Eawag)Dübendorf 8600Switzerland

water footprint(WF)measures human appropriation of water resources for consumptive use of surface and ground water(blue WF)and soil water(green WF)and for assimilating polluted water(grey WF).Questions have been often asked about the exact meaning behind the numbers from WF ***,to date environmental sustainability of WF has never been assessed at the sub-national level over *** study evaluated the environmental sustainability of blue,green and grey WF for China’s 31 mainland provinces in 2002,2007 and 2012,and identified the unsustainable ***,the total WF increased by 30%between 2002 and *** growth can be attributed to the increase of grey WF because the green and blue WF showed only a slight *** all provinces investigated in 2012,eleven showed unsustainable blue WF(sustainability index SIgreen WF,and they were distributed in China’s southern and southeastern *** grey WF was not sustainable in approximately two third of provinces(19),which were mainly located in China’s middle and northern regions and Guangdong *** than half of China’s provinces showed trends of improved SI of green and blue WF from 2002 to ***,the SI of grey WF decreased in almost two third of *** levels of WF sustainability were due to water scarcity and pollution,which intensify the degradation of local rivers and ecosystems and make restoration more *** results shed light on the policy making needed to improve sustainable water management,and ecological restoration of hotspot regions.

关键词： green water Blue water Grey water Sustainable development Ecological restoration

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water harvesting experiences from the southern and eastern Africa rainwater network

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Journal of Southeast University(English Edition) 2014年第2期30卷 186-191页

作者： Maimbo M.Malesu Jan de Leeuw Alex Oduor The World Agroforestry Centre ( ICRAF) Nairobi 30677-00100 Kenya

This paper shares experiences of the southern and eastern Africa rainwater network on rainwater *** also shares the lessons drawn from policy research awareness creation and networking building of national networks and assessment of promising water harvesting techniques in the Sub-Saharan *** concerted promotional effort of the southern and eastern Africa rainwater network has resulted in the general acceptance of rainwater harvesting as a viable option for boosting domestic water supply agricultural production and environmental *** date twelve nationally registered rainwater harvesting associations have been established which are providing leadership and capacity building in rainwater *** and donors are also aligning their policies towards providing increased financial institutional and technical support for upscaling rainwater-harvesting techniques. This paper concludes that diligent land and water management is necessary for yielding the highest benefits from *** addition to enabling policies and institutions there must be ample budgetary support to increase adoption of the technology.

关键词： rainwater harvesting blue water water scarcity policy water harvesting techniques SearNet green water

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Impacts of Climate Change on water Resources in Diyala River Basin, Iraq

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Journal of Civil Engineering and Architecture 2016年第9期10卷 1059-1074页

作者： Nahlah Abbas Saleh A Wasimi Nadhir Al-Ansari School of Engineering and Technology Central Queensland University Melbourne 3000 Australia Department of Civil Environmental and Natural Resources Engineering Lulea University of Technology Lulea 971 87 Sweden

Diyala River is the third largest tributary of the Tigris River running 445 km length and draining an area of 32,600 km2. The river is the major source of water supply for Diyala City for municipal, domestic, agriculture and other purposes. Diyala River Basin currently is suffering from water scarcity and contamination problems. Up-to-date studies have shown that blue and green waters of a basin have been demonstrating increasing variability contributing to more severe droughts and floods seemingly due to climate change. To obtain better understanding of the impacts of climate change on water resources in Diyala River Basin in near 2046-2064 and distant future 2080~2100, SWAT （soil and water assessment tool） was used. The model is first examined for its capability of capturing the basin characteristics, and then, projections from six GCMs （general circulation models） are incorporated to assess the impacts of climate change on water resources under three emission scenarios： A2, AIB and B1. The results showed deteriorating water resources regime into the future.

关键词： Diyala River SWAT model blue water green water Iraq.

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Effect of Ship Bow Overhang on water Shipping for Ship Advancing in Regular Head Waves

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Journal of Marine Science and Application 2016年第1期15卷 33-40页

作者： Abdeljalil Benmansour Benameur Hamoudi Lahouari Adjlout Department of Maritime Engineering University of Science and Technology of Oran Mohamed Boudiaf Oran 31130 Algeria

This paper presents the results of an experimental investigation dealing with the effect of bow overhang extensions on the quantity of shipping water over the foredeck in case of ships advancing in regular head waves. To perform this investigation, a series of free-running tests was conducted in regular waves using an experimental model of a multipurpose cargo ship to quantify the amount of shipping water. The tests were performed on five bow overhang variants with several combinations of wavelength and ship speed conditions. It was observed that the quantity of shipping water was affected by some parameters such as wavelength, ship speed, and bow shape in terms of an overhang extension. The results show the significant influence of an overhang extension, which is associated with the bow flare shape, on the occurrence of water shipping. These results involve the combined incoming regular waves and model speed.

关键词： water on deck shipped water amount ship model tests bow overhang green water regular head waves

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Virtual water Trade and Food Security for Iraq

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Engineering（科研） 2023年第7期15卷 417-430页

作者： Nasrat Adamo Nadhir Al-Ansari Varoujan Sissakian Jan Laue Salwan Ali Abed Al Khanfar Consultant Engineer Norrk&#246ping Sweden Department of Civil Environmental and Natural Resources Engineering Lulea University of Technology Lulea Sweden Department of Petroleum Engineering Komar University of Science and Technology Sulaimaniyah Iraq College of Science University of Al-Qadisiyah Al-Qadisiyah Iraq

Iraq depends on its water resources from the water of the Tigris and Euphrates Rivers and their tributaries. Now, the flow of these rivers is decreasing, and Iraq is experiencing a water shortage problem. The situation is expected to be graver in the future if no action is considered. It is expected that the population will be about 70 million in 2050 and about 90 million in 2070. In such a case, thus, the quantities of water available in the future will not be sufficient to produce most of the requirements of food security, whether that be from agricultural or animal products. To overcome this problem, water management planning should be based on scientific background to overcome the present and expected problems. One of the main factors to be considered should be based on scientific studies of the virtual water footprint of different food crops to provide the largest possible amount of virtual water and avoid the acute shortage of its national water from surface and ground irrigation water (blue water) and rainwater (green water), in addition to working hard to provide the largest possible amount of desalinated water and refined sewage (gray water). In addition, any strategic plan for sustainable development in the country must be comprehensive so that it is not satisfied with improving the situation in the field of food security related to water security, but rather among its other elements is community development that directly affects food security, including setting policies to reduce consumption by reducing the steady increase in population where the population rate is 2.97% now. Collective awareness and guidance programs in all the fields of water and food security are very important to be adopted, so that everyone knows that the issue of food security and what derives from it are an existential issue related to the survival of Iraq as a state and people. In this research, facts are stated so that action is to be considered to minimize the water shortage pro

关键词： Virtual water Food Security Iraq Blue water green water Grey water

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A dynamic analysis of water footprint of Jinghe River basin

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Ecological Economy 2008年第2期4卷 161-171页

作者： Geng Yanhui Min Qingwen Cheng Shengkui Wan Xin Yang Yanzhao Institute o Geographic Sciences and Natural Resources Research Chinese ACademy of Sciences Beijing 100101P. R China Graduate School Chinese Academy of Sciences Beijing 100039 P. R. China Lanzhou Climate Centet Lanzhou 730020 P. R. China

water footprint in a region is defined as the volume of water needed for the production of goods and services consumed by the local people, Ecosystem services are a kind of important services, so ecological water use is one necessary component in water footprint. water footprint is divided into green water footprint and blue water footprint but the former one is often *** this paper waterJootprint includes blue water needed by agricultural irrigation, industrial and domestic water demand, and green water needed by crops, economic forests, livestock prochtcts, forestlalands and grasslands. The study calculates the footprint of the Jinghe River basin in 1990, 1995, 2000 and 2005 with quarto methods. Results of research show that water footprints reached 164.1 ×10^8m3, 175. 69 ×10^8m3 and 178. 45 ×10^8m3 respectively in 1990, 1995 and 2000 including that of ecological water use, but reached 77.68×10^8m3, 94.24×10^8m3, 92.92×10^8m3 and 111.36 ×10^8m3 respectively excluding that of ecological water use. green *** is much more than blue water footprint; thereby, green water plays an important role in economic development and ecological construction The dynamic change of water footprints shows that blue water use increases rapidly and that the ecological water use is occupied by economie and domestic water use. The change also shows that water use is transferred from primary industry to secondary industry In primary industry, it is transferred from crops farming to forestry, and animal agriculture. The factors impelling the change include development anticipation on econonomy; government policies, readjustment of the industrial structure, population growth, the raise of urbanization level, and structurul change of consumption, low level of waler-saving and poor ability of waste water *** blue water use per unit, green water use per unit, blue water use structure and green water use structure, we analyzed the difference of the six ecologiea

关键词： water footprint Blue water green water Dynamic change Influencing factors Jinghe River basin

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