Sample records for net virtual water
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Water Footprint and Virtual Water Trade of Brazil
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Vicente de Paulo R. da Silva
2016-11-01
Full Text Available Freshwater scarcity has increased at an alarming rate worldwide; improved water management plays a vital role in increasing food production and security. This study aims to determine the water footprint of Brazil’s national food consumption, the virtual water flows associated with international trade in the main agricultural commodities, as well as water scarcity, water self-sufficiency and water dependency per Brazilian region. While previous country studies on water footprints and virtual water trade focused on virtual water importers or water-scarce countries, this is the first study to concentrate on a water-abundant virtual water-exporting country. Besides, it is the first study establishing international virtual water trade balances per state, which is relevant given the fact that water scarcity varies across states within the country, so the origin of virtual water exports matters. The results show that the average water footprint of Brazilian food consumption is 1619 m3/person/year. Beef contributes most (21% to this total. We find a net virtual water export of 54.8 billion m3/year, mainly to Europe, which imports 41% of the gross amount of the virtual water exported from Brazil. The northeast, the region with the highest water scarcity, has a net import of virtual water. The southeast, next in terms of water scarcity, shows large virtual water exports, mainly related to the export of sugar. The north, which has the most water, does not show a high virtual water export rate.
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Virtual water and water self-sufficiency in agricultural and livestock products in Brazil.
da Silva, Vicente de Paulo R; de Oliveira, Sonaly D; Braga, Célia C; Brito, José Ivaldo B; de Sousa, Francisco de Assis S; de Holanda, Romildo M; Campos, João Hugo B C; de Souza, Enio P; Braga, Armando César R; Rodrigues Almeida, Rafaela S; de Araújo, Lincoln E
2016-12-15
Virtual water trade is often considered a solution for restricted water availability in many regions of the world. Brazil is the world leader in the production and export of various agricultural and livestock products. The country is either a strong net importer or a strong net exporter of these products. The objective of this study is to determine the volume of virtual water contained in agricultural and livestock products imported/exported by Brazil from 1997 to 2012, and to define the water self-sufficiency index of agricultural and livestock products in Brazil. The indexes of water scarcity (WSI), water dependency (WDI) and water self-sufficiency (WSSI) were calculated for each Brazilian state. These indexes and the virtual water balance were calculated following the methodology developed by Chapagain and Hoekstra (2008) and Hoekstra and Hung (2005). The total water exports and imports embedded in agricultural and livestock products were 5.28 × 10 10 and 1.22 × 10 10 Gm 3 yr -1 , respectively, which results in positive virtual water balance of 4.05 × 10 10 Gm 3 yr -1 . Brazil is either a strong net importer or a strong net exporter of agricultural and livestock products among the Mercosur countries. Brazil has a positive virtual water balance of 1.85 × 10 10 Gm 3 yr -1 . The indexes used in this study reveal that Brazil is self-sufficient in food production, except for a few products such as wheat and rice. Horticultural products (tomato, onion, potato, cassava and garlic) make up a unique product group with negative virtual water balance in Brazil. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Recent History and Geography of Virtual Water Trade
Carr, Joel A.; D’Odorico, Paolo; Laio, Francesco; Ridolfi, Luca
2013-01-01
The global trade of goods is associated with a virtual transfer of the water required for their production. The way changes in trade affect the virtual redistribution of freshwater resources has been recently documented through the analysis of the virtual water network. It is, however, unclear how these changes are contributed by different types of products and regions of the world. Here we show how the global patterns of virtual water transport are contributed by the trade of different commodity types, including plant, animal, luxury (e.g., coffee, tea, and alcohol), and other products. Major contributors to the virtual water network exhibit different trade patterns with regard to these commodity types. The net importers rely on the supply of virtual water from a small percentage of the global population. However, discrepancies exist among the different commodity networks. While the total virtual water flux through the network has increased between 1986 and 2010, the proportions associated with the four commodity groups have remained relatively stable. However, some of the major players have shown significant changes in the virtual water imports and exports associated with those commodity groups. For instance, China has switched from being a net exporter of virtual water associated with other products (non-edible plant and animal products typically used for manufacturing) to being the largest importer, accounting for 31% of the total water virtually transported with these products. Conversely, in the case of The United states of America, the commodity proportions have remained overall unchanged throughout the study period: the virtual water exports from The United States of America are dominated by plant products, whereas the imports are comprised mainly of animal and luxury products. PMID:23457481
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Recent history and geography of virtual water trade.
Carr, Joel A; D'Odorico, Paolo; Laio, Francesco; Ridolfi, Luca
2013-01-01
The global trade of goods is associated with a virtual transfer of the water required for their production. The way changes in trade affect the virtual redistribution of freshwater resources has been recently documented through the analysis of the virtual water network. It is, however, unclear how these changes are contributed by different types of products and regions of the world. Here we show how the global patterns of virtual water transport are contributed by the trade of different commodity types, including plant, animal, luxury (e.g., coffee, tea, and alcohol), and other products. Major contributors to the virtual water network exhibit different trade patterns with regard to these commodity types. The net importers rely on the supply of virtual water from a small percentage of the global population. However, discrepancies exist among the different commodity networks. While the total virtual water flux through the network has increased between 1986 and 2010, the proportions associated with the four commodity groups have remained relatively stable. However, some of the major players have shown significant changes in the virtual water imports and exports associated with those commodity groups. For instance, China has switched from being a net exporter of virtual water associated with other products (non-edible plant and animal products typically used for manufacturing) to being the largest importer, accounting for 31% of the total water virtually transported with these products. Conversely, in the case of The United states of America, the commodity proportions have remained overall unchanged throughout the study period: the virtual water exports from The United States of America are dominated by plant products, whereas the imports are comprised mainly of animal and luxury products.
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Recent history and geography of virtual water trade.
Directory of Open Access Journals (Sweden)
Joel A Carr
Full Text Available The global trade of goods is associated with a virtual transfer of the water required for their production. The way changes in trade affect the virtual redistribution of freshwater resources has been recently documented through the analysis of the virtual water network. It is, however, unclear how these changes are contributed by different types of products and regions of the world. Here we show how the global patterns of virtual water transport are contributed by the trade of different commodity types, including plant, animal, luxury (e.g., coffee, tea, and alcohol, and other products. Major contributors to the virtual water network exhibit different trade patterns with regard to these commodity types. The net importers rely on the supply of virtual water from a small percentage of the global population. However, discrepancies exist among the different commodity networks. While the total virtual water flux through the network has increased between 1986 and 2010, the proportions associated with the four commodity groups have remained relatively stable. However, some of the major players have shown significant changes in the virtual water imports and exports associated with those commodity groups. For instance, China has switched from being a net exporter of virtual water associated with other products (non-edible plant and animal products typically used for manufacturing to being the largest importer, accounting for 31% of the total water virtually transported with these products. Conversely, in the case of The United states of America, the commodity proportions have remained overall unchanged throughout the study period: the virtual water exports from The United States of America are dominated by plant products, whereas the imports are comprised mainly of animal and luxury products.
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Understanding virtual water flows: A multiregion input-output case study of Victoria
Lenzen, Manfred
2009-09-01
This article explains and interprets virtual water flows from the well-established perspective of input-output analysis. Using a case study of the Australian state of Victoria, it demonstrates that input-output analysis can enumerate virtual water flows without systematic and unknown truncation errors, an issue which has been largely absent from the virtual water literature. Whereas a simplified flow analysis from a producer perspective would portray Victoria as a net virtual water importer, enumerating the water embodiments across the full supply chain using input-output analysis shows Victoria as a significant net virtual water exporter. This study has succeeded in informing government policy in Australia, which is an encouraging sign that input-output analysis will be able to contribute much value to other national and international applications.
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Goswami, Prashant; Nishad, Shiv Narayan
2015-03-20
Assessment and policy design for sustainability in primary resources like arable land and water need to adopt long-term perspective; even small but persistent effects like net export of water may influence sustainability through irreversible losses. With growing consumption, this virtual water trade has become an important element in the water sustainability of a nation. We estimate and contrast the virtual (embedded) water trades of two populous nations, India and China, to present certain quantitative measures and time scales. Estimates show that export of embedded water alone can lead to loss of water sustainability. With the current rate of net export of water (embedded) in the end products, India is poised to lose its entire available water in less than 1000 years; much shorter time scales are implied in terms of water for production. The two cases contrast and exemplify sustainable and non-sustainable virtual water trade in long term perspective.
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Virtual scarce water in China.
Feng, Kuishuang; Hubacek, Klaus; Pfister, Stephan; Yu, Yang; Sun, Laixiang
2014-07-15
Water footprints and virtual water flows have been promoted as important indicators to characterize human-induced water consumption. However, environmental impacts associated with water consumption are largely neglected in these analyses. Incorporating water scarcity into water consumption allows better understanding of what is causing water scarcity and which regions are suffering from it. In this study, we incorporate water scarcity and ecosystem impacts into multiregional input-output analysis to assess virtual water flows and associated impacts among 30 provinces in China. China, in particular its water-scarce regions, are facing a serious water crisis driven by rapid economic growth. Our findings show that inter-regional flows of virtual water reveal additional insights when water scarcity is taken into account. Consumption in highly developed coastal provinces is largely relying on water resources in the water-scarce northern provinces, such as Xinjiang, Hebei, and Inner Mongolia, thus significantly contributing to the water scarcity in these regions. In addition, many highly developed but water scarce regions, such as Shanghai, Beijing, and Tianjin, are already large importers of net virtual water at the expense of water resource depletion in other water scarce provinces. Thus, increasingly importing water-intensive goods from other water-scarce regions may just shift the pressure to other regions, but the overall water problems may still remain. Using the water footprint as a policy tool to alleviate water shortage may only work when water scarcity is taken into account and virtual water flows from water-poor regions are identified.
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Local and global perspectives on the virtual water trade
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S. Tamea
2013-03-01
Full Text Available Recent studies on fluxes of virtual water are showing how the global food and goods trade interconnects the water resources of different and distant countries, conditioning the local water balances. This paper presents and discusses the assessment of virtual water fluxes between a single country and its network of trading partners, delineating a country's virtual water budget in space and time (years 1986–2010. The fluxes between the country under study and its importing/exporting partners are visualized with a geographical representation shaping the trade network as a virtual river/delta. Time variations of exchanged fluxes are quantified to show possible trends in the virtual water balance, while characterizing the time evolution of the trade network and its composition in terms of product categories (plant-based, animal-based, luxury food, and non-edible. The average distance traveled by virtual water to arrive to the place of consumption is also introduced as a new measure for the analysis of globalization of the virtual water trade. Using Italy as an example, we find that food trade has a steadily growing importance compared to domestic production, with a major component represented by plant-based products, and luxury products taking an increasingly larger share (26% in 2010. In 2010 Italy had an average net import of 55 km3 of virtual water (38 km3 in 1986, a value which poses the country among the top net importers in the world. On average each cubic meter of virtual water travels nearly 4000 km before entering Italy, while export goes to relatively closer countries (average distance: 2600 km, with increasing trends in time which are almost unique among the world countries. Analyses proposed for Italy are replicated for 10 other world countries, triggering similar investigations on different socio-economic actualities.
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Local and global perspectives on the virtual water trade
Tamea, S.; Allamano, P.; Carr, J. A.; Claps, P.; Laio, F.; Ridolfi, L.
2013-03-01
Recent studies on fluxes of virtual water are showing how the global food and goods trade interconnects the water resources of different and distant countries, conditioning the local water balances. This paper presents and discusses the assessment of virtual water fluxes between a single country and its network of trading partners, delineating a country's virtual water budget in space and time (years 1986-2010). The fluxes between the country under study and its importing/exporting partners are visualized with a geographical representation shaping the trade network as a virtual river/delta. Time variations of exchanged fluxes are quantified to show possible trends in the virtual water balance, while characterizing the time evolution of the trade network and its composition in terms of product categories (plant-based, animal-based, luxury food, and non-edible). The average distance traveled by virtual water to arrive to the place of consumption is also introduced as a new measure for the analysis of globalization of the virtual water trade. Using Italy as an example, we find that food trade has a steadily growing importance compared to domestic production, with a major component represented by plant-based products, and luxury products taking an increasingly larger share (26% in 2010). In 2010 Italy had an average net import of 55 km3 of virtual water (38 km3 in 1986), a value which poses the country among the top net importers in the world. On average each cubic meter of virtual water travels nearly 4000 km before entering Italy, while export goes to relatively closer countries (average distance: 2600 km), with increasing trends in time which are almost unique among the world countries. Analyses proposed for Italy are replicated for 10 other world countries, triggering similar investigations on different socio-economic actualities.
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Economic aspects of virtual water trade
Oki, Taikan; Yano, Shinjiro; Hanasaki, Naota
2017-04-01
Although water is rarely traded over long distances by itself, the total weight of the water consumed to produce traded commodities exceeds the weight of any other commodity traded in the world. This concept is known as virtual water trade. Although space-/time-/commodity-based quantification has been conducted extensively, the underlying causes of this peculiar feature have thus far received little exploration. Here, we use estimates of water consumption from a global hydrological model and statistical data related to food trade to elucidate three facts that explain the fundamental nature of virtual water trade with respect to alleviating water scarcity. First, we quantitatively illustrate the unique position of water among commodities based on its unit price and quantity of sales. Water has an extremely low unit price, and a tremendous volume of water is consumed per person each day. Second, we show that rich but water-scarce countries tend to reduce local water consumption by importing virtual water. Third, we demonstrate that nations characterized by net virtual water exports have higher water resources and income per capita and that no countries fall below a certain threshold with respect to both GDP and water resources. These points suggest that the virtual water trade is explained by economic characteristics of water and that sustainable development depends on promoting the co-development of poverty alleviation and water resource development.
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Shi, J.; Liu, J.; Pinter, L.
2014-04-01
China has dramatically increased its virtual water import over recent years. Many studies have focused on the quantity of traded virtual water, but very few go into analysing geographic distribution and the properties of China's virtual water trade network. This paper provides a calculation and analysis of the crop-related virtual water trade network of China based on 27 major primary crops between 1986 and 2009. The results show that China is a net importer of virtual water from water-abundant areas of North America and South America, and a net virtual water exporter to water-stressed areas of Asia, Africa, and Europe. Virtual water import is far larger than virtual water export, and in both import and export a small number of trade partners control the supply chain. Grain crops are the major contributors to virtual water trade, and among grain crops, soybeans, mostly imported from the US, Brazil and Argentina, are the most significant. In order to mitigate water scarcity and secure the food supply, virtual water should actively be incorporated into national water management strategies. And the sources of virtual water import need to be further diversified to reduce supply chain risks and increase resilience.
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Zhang, Zhuoying; Yang, Hong; Shi, Minjun
2016-04-01
The North China Plain is the most water scarce region in China. Its water security is closely relevant to interregional water movement, which can be realized by real water transfers and/or virtual water transfers. This study investigates the roles of virtual water trade and real water transfer using Interregional Input-Output model. The results show that the region is receiving 19.4 billion m3/year of virtual water from the interregional trade, while exporting 16.4 billion m3/year of virtual water in the international trade. In balance, the region has a net virtual water gain of 3 billion m3/year from outside. Its virtual water inflow is dominated by agricultural products from other provinces, totalling 16.6 billion m3/year, whilst its virtual water export is dominated by manufacturing sectors to other countries, totalling 11.7 billion m3/year. Both virtual water import and real water transfer from South to North Water Diversion Project are important water supplements for the region. The results of this study provide useful scientific references for the establishment of combating strategies to deal with the water scarcity in the future.
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Shi, J.; Liu, J.; Pinter, L.
2013-09-01
China has dramatically increased its virtual water import unconsciously for recent years. Many studies have focused on the quantity of traded virtual water but very few go into analysing geographic distribution and the properties of China's virtual water trade network. This paper provides a calculation and analysis of the crop-related virtual water trade network of China based on 27 major primary crops between 1986 and 2009. The results show that China is a net importer of virtual water from water-abundant areas of North and South America, and a net virtual water exporter to water-stressed areas of Asia, Africa, and Europe. Virtual water import is far larger than virtual water export and in both import and export a small number of trade partners control the supply chain. Grain crops are the major contributors to virtual water trade, and among grain crops soybeans, mostly imported from the US, Brazil and Argentina are the most significant. As crop yield and crop water productivity in North and South America are generally higher than those in Asia and Africa, the effect of China's crop-related virtual water trade positively contributes to optimizing crop water use efficiency at the global scale. In order to mitigate water scarcity and secure the food supply, virtual water should be actively incorporated into national water management strategies. From the national perspective, China should reduce the export and increase the import of water-intensive crops. But the sources of virtual water import need to be further diversified to reduce supply chain risks and increase resilience.
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Virtual water: Virtuous impact? : the unsteady state of virtual water
Roth, D.; Warner, J.F.
2008-01-01
“Virtual water,” water needed for crop production, is now being mainstreamed in the water policy world. Relying on virtual water in the form of food imports is increasingly recommended as good policy for water-scarce areas. Virtual water globalizes discussions on water scarcity, ecological
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CSIR Research Space (South Africa)
Lindeque, M
2013-01-01
Full Text Available the national grid. The unfortunate situation with water is that there is no replacement technology for water. Water can be supplied from many different sources. A net zero energy development will move closer to a net zero water development by reducing...
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Virtual water flows in the international trade of agricultural products of China.
Zhang, Yu; Zhang, Jinhe; Tang, Guorong; Chen, Min; Wang, Lachun
2016-07-01
With the rapid development of the economy and population, water scarcity and poor water quality caused by water pollution have become increasingly severe in China. Virtual water trade is a useful tool to alleviate water shortage. This paper focuses on a comprehensive study of China's international virtual water flows from agricultural products trade and completes a diachronic analysis from 2001 to 2013. The results show that China was in trade surplus in relation to the virtual water trade of agricultural products. The exported virtual water amounted to 29.94billionm(3)/yr. while 155.55billionm(3)/yr. was embedded in imported products. The trend that China exported virtual water per year was on the decline while the imported was on a rising trend. Virtual water trade of China was highly concentrated. Not all of the exported products had comparative advantages in virtual water content. Imported products were excessively concentrated on water intensive agricultural products such as soya beans, cotton, and palm oil. The exported virtual water mainly flowed to the Republic of Korea, Hong Kong of China and Japan, while the imported mainly flowed from the United States of America, Brazil and Argentina. From the ethical point of view, the trade partners were classified into four types in terms of "net import" and "water abundance": mutual benefit countries, such as Australia and Canada; unilateral benefit countries, such as Mongolia and Norway; supported countries, such as Egypt and Singapore; and double pressure countries, such as India and Pakistan. Virtual water strategy refers to water resources, agricultural products and human beings. The findings are beneficial for innovating water resources management system, adjusting trade structure, ensuring food security in China, and promoting the construction of national ecological security system. Copyright © 2016 Elsevier B.V. All rights reserved.
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Mubako, S. T.; Ruddell, B. L.; Mayer, A. S.
2013-12-01
The impact of human water uses and economic pressures on freshwater ecosystems is of growing interest for water resource management worldwide. This case study for a water-rich watershed in the Great Lakes region links the economic pressures on water resources as revealed by virtual water trade balances to the nature of the economic water use and the associated impacts on the freshwater ecosystem. A water accounting framework that combines water consumption data and economic data from input output tables is applied to quantify localized virtual water imports and exports in the Kalamazoo watershed which comprises ten counties. Water using economic activities at the county level are conformed to watershed boundaries through land use-water use relationships. The counties are part of a region implementing the Michigan Water Withdrawal Assessment Process, including new regulatory approaches for adaptive water resources management under a riparian water rights framework. The results show that at local level, there exists considerable water use intensity and virtual water trade balance disparity among the counties and between water use sectors in this watershed. The watershed is a net virtual water importer, with some counties outsourcing nearly half of their water resource impacts, and some outsourcing nearly all water resource impacts. The largest virtual water imports are associated with agriculture, thermoelectric power generation and industry, while the bulk of the exports are associated with thermoelectric power generation and commercial activities. The methodology is applicable to various spatial levels ranging from the micro sub-watershed level to the macro Great Lakes watershed region, subject to the availability of reliable water use and economic data.
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[Research on the virtual water composition and virtual water trade for agriculture in Beijing].
Wang, Hong-rui; Wang, Yan; Wang, Jun-hong; Dong, Yan-yan; Han, Zhao-xing
2007-12-01
Based on the irrigation norm of typical district and county, and revised by the isoline map of Chinese crops water demand, the change of crops program was analyzed as well as the agricultural water use and its GDP benefits. Then the virtual water was calculated for years. At last, the input-output method was used to calculate the trade of virtual water in Beijing. As the results, the virtual water for cereal crops has been decreasing in Beijing, from 1.832 x 10(9) m3 in 1990 to 4.283 x 10(8) m3 in 2004. Otherwise the virtual water for technical crops has been increasing, which is from 9.06 x 10(8) m3 in 1990 to 1.492 x 10(9) m3 in 2004. On the whole, the virtual water for crops has been decreasing in Beijing. From the angle of primary products Beijing is a virtual water importing area. Virtual water importing of annual average is 2.37 x 10(8) m3, which is about 5.93% of the total water of Beijing. Virtual water has been an important supplement of local real water of Beijing.
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Evaluation of Virtual Water Trade by the Industrial Sector of Zanjan Province
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Morteza Tahami Pourzarandi
2017-07-01
Full Text Available Water crisis is of utmost importance due to the growing demand and consumption of water, especially in developing countries where its production and food security are facing serious challenges. Virtual water trade has been proposed as one strategy to combat the water scarcity crisis in arid and semi-arid regions. The strategy is based on the import of food and water-intensive supplies from neighboring regions that enjoy adequate supplies of water. Given the fact that the industrial sector has been proposed to serve as the basis of development in Zanjan Province, the present study was conducted to investigate the virtual water trade by the industrial sector in this province. For the purposes of this study, data from the statistical period 2010-2011 were obtained from the Statistical Center of Iran on enterprises employing ten member staffs or above. The data were used to categorize the industries surveyed, their water demands, and products to estimate the quantities of water needed for their continued operation. It was found that the highest quantities of virtual water in Zanjan are allocated to coking and petroleum plants, paper and cellulosic industries, and food and beverage processing factories with average values of 32.70, 26.14, and 11.63 cubic meters per million Rials, respectively. In addition, the total amount of virtual water exported from the industrial units operating in Zanjan Province is estimated at about 3.10 MCM, 50% of which belongs to base metal production. Conclusion: Our findings show that the industrial sector in Zanjan Province is a net exporter of virtual water.
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Virtual water trade of agricultural products: A new perspective to explore the Belt and Road.
Zhang, Yu; Zhang, Jin-He; Tian, Qing; Liu, Ze-Hua; Zhang, Hong-Lei
2018-05-01
The Belt and Road is an initiative of cooperation and development that was proposed by China. Moreover, most of the spanning countries faced water shortages and agriculture consumed a lot of water. Virtual water links water, food and trade and is an effective tool to ease water shortages. Therefore, this paper aims to understand the Belt and Road from the new perspective of virtual water trade of agricultural products. We considered agricultural products trade from 2001 to 2015. On the whole, the results indicated that China was in virtual water trade surplus with the countries along the Belt and Road. However, in terms of each country, >40 spanning countries were in virtual water trade surplus with China and eased water shortages. Russia had the largest net imported virtual water from China. Furthermore, the proportion of the grey water footprint that China exported to the spanning countries was much higher than that imported, no matter from the whole or different geographical regions. Moreover, more than half of the countries' virtual water trade with China conformed to the virtual water strategy, which helped to ease water crises. Furthermore, the products that they exported to China were mainly advantageous products that each spanning countries have. Virtual water trade is a new perspective to explore the Belt and Road. Agricultural products trade with China definitely benefits both the countries along the Belt and Road and China from the perspective of virtual water. The findings are beneficial for the water management of the countries along the Belt and Road and China, alleviating water shortages, encouraging the rational allocation of water resources in the various departments. They can provide references for optimizing trade structures as well. Copyright © 2017 Elsevier B.V. All rights reserved.
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The virtual water content of major grain crops and virtual water flows between regions in China.
Sun, Shi-Kun; Wu, Pu-Te; Wang, Yu-Bao; Zhao, Xi-Ning
2013-04-01
The disproportionate distribution of arable land and water resources has become a bottleneck for guaranteeing food security in China. Virtual water and virtual water trade theory have provided a potential solution to improve water resources management in agriculture and alleviate water crises in water-scarce regions. The present study evaluates the green and blue virtual water content of wheat, maize and rice at the regional scale in China. It then assesses the water-saving benefits of virtual water flows related to the transfer of the three crops between regions. The national average virtual water content of wheat, maize and rice were 1071 m(3) per ton (50.98% green water, 49.02% blue water ), 830 m(3) per ton (76.27% green water, 23.73% blue water) and 1294 m(3) per ton (61.90% green water, 38.10% blue water), respectively. With the regional transfer of wheat, maize and rice, virtual water flows reached 30.08 Gm(3) (59.91% green water, 40.09% blue water). Meanwhile, China saved 11.47 Gm(3) green water, while it consumed 7.84 Gm(3) more blue water than with a no-grain transfer scenario in 2009. In order to guarantee food security in China, the government should improve water productivity (reduce virtual water content of crops) during the grain production process. Meanwhile, under the preconditions of economic feasibility and land-water resources availability, China should guarantee the grain-sown area in southern regions for taking full advantage of green water resources and to alleviate the pressure on water resources. © 2012 Society of Chemical Industry.
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Liu, Jing; Wu, Pute; Wang, Yubao; Zhao, Xining; Sun, Shikun; Cao, Xinchun
2014-11-01
Analysis of cropping patterns is a prerequisite for their optimisation, and evaluation of virtual water flows could shed new light on water resources management. This study is intended to explore the effects of cropping pattern changes between 1960 and 2008 on virtual water flows related to crops transfer in the Hetao irrigation district, China. (1) The sown area of crops increased at an average rate of 3.57 × 10(3) ha year(-1) while the proportion of sown grain crops decreased from 92.83% in the 1960s to 50.22% in the 2000s. (2) Virtual water content decreased during the study period while net virtual water exports increased since the 1980s. (3) Assuming that the cropping pattern was constant and was equal to the average 1960s value, accumulated net virtual water export in 1980-2008 would have been 4.76 × 10(9) m(3) greater than that in the actual cropping pattern scenario. Cropping pattern changes in the Hetao irrigation district could not only be seen as resulting from the pursuit for higher economic returns, but also as a feedback response to limited water resources. A systematic framework is still needed for future cropping pattern planning by taking food security, continued agricultural expansion and other constraints into consideration. © 2014 Society of Chemical Industry.
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Intra-EU agricultural trade, virtual water flows and policy implications.
Antonelli, M; Tamea, S; Yang, H
2017-06-01
The development of approaches to tackle the European Union (EU) water-related challenges and shift towards sustainable water management and use is one of the main objectives of Horizon 2020, the EU strategy to lead a smart, sustainable and inclusive growth. The EU is an increasingly water challenged area and is a major agricultural trader. As agricultural trade entails an exchange of water embodied in goods as a factor of production, this study investigates the region's water-food-trade nexus by analysing intra-regional virtual water trade (VWT) in agricultural products. The analysed period (1993-2011) comprises the enactment of the Water Framework Directive (WFD) in the year 2000. Aspects of the VWT that are relevant for the WFD are explored. The EU is a net importer of virtual water (VW) from the rest of the world, but intra-regional VWT represents 46% of total imports and 75% of total exports. Five countries account for 60% of total VW imports (Germany, France, Italy, The Netherlands, Belgium) and 65% of total VW exports (The Netherlands, France, Germany, Belgium and Spain). Intra-EU VWT more than doubled over the period considered, while trade with extra-EU countries did not show such a marked trend. In the same period, blue VWT increased significantly within the region and net import from the rest of the world slightly decreased. Water scarce countries, such as Spain and Italy, are major exporters of blue water in the region. The traded volumes of VW have been increasing almost monotonically over the years, and with a substantial increase after 2000. The overall trend in changes in VWT does not seem to be in accordance with the WFD goals. This study demonstrated that VWT analyses can help evaluate intertwining effects of water, agriculture and trade policies which are often made separately in respective sectors. Copyright © 2017 Elsevier B.V. All rights reserved.
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Katyaini, Suparana; Barua, Anamika
2017-08-01
India is the largest global freshwater user despite being highly water scarce. Agriculture is largest consumer of water and is most affected by water scarcity. Water scarcity is a persistent challenge in India, due to a gap in science and policy spheres. Virtual Water (VW) flows concept to mitigate water scarcity is at the science-policy interface. The paper aims to address the gap in VW research in India by first analyzing the interstate VW-flows embedded in food grains, and then linking these VW-flows with the water scarcity situation in the states, and elements of state and national water policies for the postreforms, and recovery periods of India's agriculture. There were net water savings (WS) of 207.5 PL during 1996-2014, indicating sustainable flows at the national level. WS increased from 11.2 TL/yr (1996-2005) to 25931.7 TL/yr (2005-2014), with the increase in interstate movement of food grains, and yield. However, unsustainable flows are seen at subnational scale, as VW-flows are from highly water-scarce states in North to highly water-scarce states in West and South. These flows are causing a concentration of water scarcity in water-scarce zones/states. Net VW imports were found to be driven by larger population and net VW exports by arable land. Further, the absence of state water policy cripples water management. Therefore, the paper argues that there is a need to rethink policy decisions on agriculture at the national and state level by internalizing water as a factor of production, through VW research.
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Water Footprint and Virtual Water Trade of Brazil
da Silva, Vicente de Paulo R.; de Oliveira, Sonaly D.; Hoekstra, Arjen Ysbert; Neto, Jose Dantas; Campos, João Hugo B.C.; Braga, Celia C.; Araújo, Lincoln Eloi; Oliveira Aleixo, Danilo; de Brito, Jose Ivaldo B.; de Souza, Marcio Dionisio; de Holanda, Romildo M.
2016-01-01
Freshwater scarcity has increased at an alarming rate worldwide; improved water management plays a vital role in increasing food production and security. This study aims to determine the water footprint of Brazil’s national food consumption, the virtual water flows associated with international trade in the main agricultural commodities, as well as water scarcity, water self-sufficiency and water dependency per Brazilian region. While previous country studies on water footprints and virtual w...
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[Virtual water content of livestock products in China].
Wang, Hong-rui; Wang, Jun-hong
2006-04-01
The paper expatiated the virtual water content concept of livestock products and the study meaning on developing virtual water trade of livestock products in China, then summarized the calculation methods on virtual water and virtual water trade of livestock products. Based on these, the paper analyzed and researched every province virtual water content of livestock products in details, then elicited various situation of every province virtual water content of livestock products in China by year. Moreover, it compared virtual water content of livestock products with local water resources. The study indicated the following results: (1) The virtual water content of livestock products is increasing rapidly in China recently, especially poultry eggs and pork. (2) The distribution of virtual water content of livestock products is not balanced, mainly lies in North China, East China and so on; (3) The increasing production of livestock in Beijing City, Tianjin City, Hebei, Nei Monggol, Liaononing, Jilin, Shandong, Henan and Ningxia province and autonom ous region will bring pressure to local water shortage.
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WaterNet: The NASA water cycle solutions network - Danubian regional applications
International Nuclear Information System (INIS)
Matthews, Dave; Brilly, Mitja; Kobold, Mira; Zagar, Mark; Houser, Paul
2008-01-01
WaterNet is a new international network of researchers, stakeholders, and end-users of remote sensing tools that will benefit the water resources management community. This paper provides an overview and it discusses the concept of solutions networks focusing on the WaterNet. It invites Danubian research and applications teams to join our WaterNet network. The NASA Water cycle Solutions Network's goal is to improve and optimize the sustained ability of water cycle researchers, stakeholders, organizations and networks to interact, identify, harness, and extend NASA research results to augment decision support tools and meet national needs. Our team will develop WaterNet by engaging relevant NASA water cycle research resources and community-of-practice organizations, to develop what we term an 'actionable database' that can be used to communicate and connect NASA Water cycle research Results (NWRs) towards the improvement of water-related Decision Support Tools (DSTs). Recognizing that the European Commission and European Space Agency have also developed many related Water Research products (EWRs), we seek to learn about these and network with the EU teams to include their information in the WaterNet actionable data base and Community of Practice. WaterNet will then develop strategies to connect researchers and decision-makers via innovative communication strategies, improved user access to NASA and EU - Danubian resources, improved water cycle research community appreciation for user requirements, improved policymaker, management and stakeholder knowledge of research and application products, and improved identification of pathways for progress. Finally, WaterNet will develop relevant benchmarking and metrics, to understand the network's characteristics, to optimize its performance, and to establish sustainability. This paper provides examples of several NASA products based on remote sensing and land data assimilation systems that integrate remotely sensed and in
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Worse than imagined: Unidentified virtual water flows in China.
Cai, Beiming; Wang, Chencheng; Zhang, Bing
2017-07-01
The impact of virtual water flows on regional water scarcity in China had been deeply discussed in previous research. However, these studies only focused on water quantity, the impact of virtual water flows on water quality has been largely neglected. In this study, we incorporate the blue water footprint related with water quantity and grey water footprint related with water quality into virtual water flow analysis based on the multiregional input-output model of 2007. The results find that the interprovincial virtual flows accounts for 23.4% of China's water footprint. The virtual grey water flows are 8.65 times greater than the virtual blue water flows; the virtual blue water and grey water flows are 91.8 and 794.6 Gm 3 /y, respectively. The use of the indicators related with water quantity to represent virtual water flows in previous studies will underestimate their impact on water resources. In addition, the virtual water flows are mainly derived from agriculture, chemical industry and petroleum processing and the coking industry, which account for 66.8%, 7.1% and 6.2% of the total virtual water flows, respectively. Virtual water flows have intensified both quantity- and quality-induced water scarcity of export regions, where low-value-added but water-intensive and high-pollution goods are produced. Our study on virtual water flows can inform effective water use policy for both water resources and water pollution in China. Our methodology about virtual water flows also can be used in global scale or other countries if data available. Copyright © 2017 Elsevier Ltd. All rights reserved.
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U-Net/SLE: A Java-Based User-Customizable Virtual Network Interface
Directory of Open Access Journals (Sweden)
Matt Welsh
1999-01-01
Full Text Available We describe U‐Net/SLE (Safe Language Extensions, a user‐level network interface architecture which enables per‐application customization of communication semantics through downloading of user extension applets, implemented as Java classfiles, to the network interface. This architecture permits applications to safely specify code to be executed within the NI on message transmission and reception. By leveraging the existing U‐Net model, applications may implement protocol code at the user level, within the NI, or using some combination of the two. Our current implementation, using the Myricom Myrinet interface and a small Java Virtual Machine subset, allows host communication overhead to be reduced and improves the overlap of communication and computation during protocol processing.
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Virtual water trade and bilateral conflicts
De Angelis, Enrico; Metulini, Rodolfo; Bove, Vincenzo; Riccaboni, Massimo
2017-12-01
In light of growing water scarcity, virtual water, or the water embedded in key water-intensive commodities, has been an active area of debate among practitioners and academics alike. As of yet, however, there is no consensus on whether water scarcity affects conflict behavior and we still lack empirical research intending to account for the role of virtual water in affecting the odds of militarized disputes between states. Using quantitative methods and data on virtual water trade, we find that bilateral and multilateral trade openness reduce the probability of war between any given pair of countries, which is consistent with the strategic role of this important commodity and the opportunity cost associated with the loss of trade gains. We also find that the substantive effect of virtual water trade is comparable to that of oil and gas, the archetypal natural resources, in determining interstate conflicts' probability.
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Diaz-Alcaide, Silvia; Martinez-Santos, Pedro; Willaarts, Barbara; Hernández-Moreno, Enrique; Llamas, M. Ramon
2015-04-01
Water footprint assessments have gradually gained recognition as valuable tools for water management, to the point that they have been officially incorporated to water planning in countries such as Spain. Adequate combinations of the virtual water and water footprint concepts present the potential to link a broad range of sectors and issues, thus providing appropriate frameworks to support optimal water allocation and to inform production and trade decisions from the water perspective. We present the results of a regional study carried out in Cantabria, a 5300 km2 autonomous region located in northern Spain. Our approach deals with the municipal, shire and regional scales, combining different methods to assess each of the main components of Cantabria's water footprint (agriculture, livestock, forestry, industry, mining, tourism, domestic use and reservoirs), as well as exploring the significance of different approaches, assumptions and databases in the overall outcomes. The classic water footprint method is coupled with extended water footprint analyses in order to provide an estimate of the social and economic value of each sector. Finally, virtual water imports and exports are computed between Cantabria and the rest of Spain and between Cantabria and the world. The outcome of our work (a) highlights the paramount importance of green water (mostly embedded in pastures) in the region's water footprint and virtual water exports; (b) establishes the role of the region as a net virtual water exporter; (c) shows the productivity of water (euro/m3 and jobs/m3) to be highest in tourism and lowest in agriculture and livestock; and (d) demonstrates that statistical databases are seldom compiled with water footprint studies in mind, which is likely to introduce uncertainties in the results. Although our work shows that there is still plenty of room for improvement in regional-scale water footprint assessments, we contend that the available information is sufficient to
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(Virtual) Water-repellent Law? Why Legal Studies Should Be Brought Into the Virtual Water Debate
Turrini, Paolo
2014-05-01
Virtual water studies are a marvelous example of the much praised "interdisciplinary approach", efficaciously intertwining many threads woven by scholars of very diverse fields of research. After all, if water is an object of biological interest and the word "virtual" becomes especially significant in the framework of the international trade flows, why should agronomists and economists not work together? And, with them, hydrologists, environmental engineers, network analysis experts… either working side by side or, at least, following one another's steps. Browsing the relevant academic literature one may notice that a vast array of disciplines is dealing with the topic. As a consequence, it may come as a surprise that lawyers seem to have remained almost deaf to the charming call of virtual water. A social science thoroughly "social" even if sometimes deemed (also by its practitioners) akin to humanities - and for this reason not always timely in catching the hints by hard sciences - law has a lot to say about virtual water and its manifold aspects. And it is so, in my opinion, in at least two respects. First of all, legal provisions can be determinants of social facts no less than other types of norms, such as physical or economic laws. Law shapes the human behavior by giving incentives or establishing constraints to the conduct of virtually any kind of social actor, be they farmers needing to decide what to grow, entrepreneurs willing to invest in the water market, or governments requested to address their communities' problems. All of them will make their choices in consideration of the costs, opportunities, and limits set by a number of regulations. In the second place, and strictly connected with the first reason, law may offer some answers to the challenges that virtual water and, more in general, the water-food nexus bring with them. In fact, understanding the way legal provisions affect the taking of decisions in the water sector, one may try to devise
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Virtual water transfers unlikely to redress inequality in global water use
International Nuclear Information System (INIS)
Seekell, D A; D'Odorico, P; Pace, M L
2011-01-01
The distribution of renewable freshwater resources between countries is highly unequal and 80% of humanity lives in regions where water security is threatened. The transfer of agricultural and industrial products to areas where water is limited through global trade may have potential for redressing water imbalances. These transfers represent 'virtual water' used in commodity production. We evaluated the current water-use inequality between countries and the potential of virtual water transfers to equalize water use among nations using multiple statistical measures of inequality. Overall, the actual use of renewable water resources is relatively equal even though the physical distribution of renewable water resources is highly unequal. Most inequality (76%) in water use is due to agricultural production and can be attributed to climate and arable land availability, not social development status. Virtual water use is highly unequal and is almost completely explained by social development status. Virtual water transfer is unlikely to increase water-use equality primarily because agricultural water use dominates national water needs and cannot be completely compensated by virtual water transfers.
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Virtual water transfers unlikely to redress inequality in global water use
Energy Technology Data Exchange (ETDEWEB)
Seekell, D A; D' Odorico, P; Pace, M L [Department of Environmental Sciences, University of Virginia, Charlottesville, VA (United States)
2011-04-15
The distribution of renewable freshwater resources between countries is highly unequal and 80% of humanity lives in regions where water security is threatened. The transfer of agricultural and industrial products to areas where water is limited through global trade may have potential for redressing water imbalances. These transfers represent 'virtual water' used in commodity production. We evaluated the current water-use inequality between countries and the potential of virtual water transfers to equalize water use among nations using multiple statistical measures of inequality. Overall, the actual use of renewable water resources is relatively equal even though the physical distribution of renewable water resources is highly unequal. Most inequality (76%) in water use is due to agricultural production and can be attributed to climate and arable land availability, not social development status. Virtual water use is highly unequal and is almost completely explained by social development status. Virtual water transfer is unlikely to increase water-use equality primarily because agricultural water use dominates national water needs and cannot be completely compensated by virtual water transfers.
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[Distribution of virtual water of crops in Beijing].
Wang, Hong-Rui; Dong, Yan-Yan; Wang, Jun-Hong; Wang, Yan; Han, Zhao-Xing
2007-11-01
Virtual water content of grains and vegetables in Beijing's districts is calculated and analyzed for many years by irrigating water quota method, which is compared with the distribution and exploitation of groundwater in Beijing. The results indicate the virtual water content of grains shows a downward trend in all the districts, but the grain production in Yanqing district brings great pressure to the local groundwater. Secondly, the virtual water content of vegetables shows an upward trend in Shunyi District, Daxing district and Pinggu District and is accounting for more and more gradually. Thirdly, the total virtual water volume of grains is decreasing, and the total virtual water volume of vegetables is increasing and the total virtual water volume of crops in Beijing is reducing in recent years, which corresponds with the structural adjustment of policies.
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Virtual water trade and development in Africa
Konar, Megan; Caylor, Kelly
2014-05-01
A debate has long existed on the relationships between human population, natural resources, and development. Recent research has expanded this debate to include the impacts of trade; specifically, virtual water trade, or the water footprint of traded commodities. We conduct an empirical analysis of the relationships between virtual water trade, population, and development in Africa. We find that increases in virtual water imports do not lead to increases in population growth nor do they diminish human welfare. We establish a new index of virtual water trade openness and show that levels of undernourishment tend to fall with increased values of virtual water trade openness. Countries with small dam storage capacity obtain a higher fraction of their agricultural water requirements from external sources, which may indicate implicit `infrastructure sharing' across nations. Globally, increased crop exports tends to correlate with increased crop water use efficiency, though this relationship does not hold for Africa. However, internal African trade is much more efficient in terms of embodied water resources than any other region in the world. Thus, internal African trade patterns may be compensating for poor internal production systems.
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Virtual water trade and development in Africa
Directory of Open Access Journals (Sweden)
M. Konar
2013-10-01
Full Text Available A debate has long existed on the relationships between human population, natural resources, and development. Recent research has expanded this debate to include the impacts of trade; specifically, virtual water trade, or the water footprint of traded commodities. We conduct an empirical analysis of the relationships between virtual water trade, population, and development in Africa. We find that increases in virtual water imports do not lead to increases in population growth nor do they diminish human welfare. We establish a new index of virtual water trade openness and show that levels of undernourishment tend to fall with increased values of virtual water trade openness. Countries with small dam storage capacity obtain a higher fraction of their agricultural water requirements from external sources, which may indicate implicit "infrastructure sharing" across nations. Globally, increased crop exports tend to correlate with increased crop water use efficiency, though this relationship does not hold for Africa. However, internal African trade is much more efficient in terms of embodied water resources than any other region in the world. Thus, internal African trade patterns may be compensating for poor internal production systems.
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Determinants of virtual water flows in the Mediterranean.
Fracasso, Andrea; Sartori, Martina; Schiavo, Stefano
2016-02-01
The aim of the paper is to investigate the main determinants of the bilateral virtual water (water used in the production of a commodity or service) flows associated with international trade in agricultural goods across the Mediterranean basin. We consider the bilateral gross flows of virtual water in the area and study what export-specific and import-specific factors are significantly associated with virtual water flows. We follow a sequential approach. Through a gravity model of trade, we obtain a "refined" version of the variable we aim to explain, one that is free of the amount of flows due to pair-specific factors affecting bilateral trade flows and that fully reflects the impact of country-specific determinants of virtual water trade. A number of country-specific potential explanatory variables, ranging from water endowments to trade barriers, from per capita GDP to irrigation prices, is presented and tested. To identify the variables that help to explain the bilateral flows of virtual water, we adopt a model selection procedure based on model averaging. Our findings confirm one of the main controversial results in the literature: larger water endowments do not necessarily lead to a larger 'export' of virtual water, as one could expect. We also find some evidence that higher water irrigation prices reduce (increase) virtual water 'exports' ('imports'). Copyright © 2015 Elsevier B.V. All rights reserved.
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Virtual water trade: an assessment of water use efficiency in the international food trade
Directory of Open Access Journals (Sweden)
H. Yang
2006-01-01
Full Text Available Amid an increasing water scarcity in many parts of the world, virtual water trade as both a policy instrument and practical means to balance the local, national and global water budget has received much attention in recent years. Building upon the knowledge of virtual water accounting in the literature, this study assesses the efficiency of water use embodied in the international food trade from the perspectives of exporting and importing countries and at the global and country levels. The investigation reveals that the virtual water flows primarily from countries of high crop water productivity to countries of low crop water productivity, generating a global saving in water use. Meanwhile, the total virtual water trade is dominated by green virtual water, which constitutes a low opportunity cost of water use as opposed to blue virtual water. A sensitivity analysis, however, suggests high uncertainties in the virtual water accounting and the estimation of the scale of water saving. The study also raises awareness of the limited effect of water scarcity on the global virtual water trade and the negative implications of the global water saving for the water use efficiency and food security in importing countries and the environment in exporting countries. The analysis shows the complexity in evaluating the efficiency gains in the international virtual water trade. The findings of the study, nevertheless, call for a greater emphasis on rainfed agriculture to improve the global food security and environmental sustainability.
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Directory of Open Access Journals (Sweden)
Pier Paolo Miglietta
2018-02-01
Full Text Available The management of natural resources in economic activities has become a fundamental issue when considering the perspective of sustainable development. It is necessary to rethink every process in order to reach efficiency from different points of view, not only environmentally but also economically. Water scarcity is growing because of economic and population growth, climate change, and the increasing water demand. Currently, agri-food represents the most water consumptive sector, and the increasing importance of international trade in this industry puts freshwater issues in a global context that should be analyzed and regulated by sustainable policies. This analysis is focused on virtual water flows and economic water productivity related to the wine trade, and aims to evaluate water loss/savings achieved through bilateral trade relations. The choice fell on Italy, the first wine producer in the world, and the Balkan countries. The latter are new markets for wine production/consumption, in which Italian wines are strongly positioned for different reasons. The results show that, from a national point of view and considering wine trade, Italy exports water in virtual form to the Balkan countries, more than it imports, so that in effect it partially uses its own water resources for the wine supply of the Balkans. The latter, on the other hand, being a net importer of wine, partially depends on Italian water resources and exerts less pressure on their own water basins in the supporting wine supply. We also observed that the wine trade between Italy and the Balkans implies global water savings.
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A Method for Modeling the Virtual Instrument Automatic Test System Based on the Petri Net
Institute of Scientific and Technical Information of China (English)
MA Min; CHEN Guang-ju
2005-01-01
Virtual instrument is playing the important role in automatic test system. This paper introduces a composition of a virtual instrument automatic test system and takes the VXIbus based a test software platform which is developed by CAT lab of the UESTC as an example. Then a method to model this system based on Petri net is proposed. Through this method, we can analyze the test task scheduling to prevent the deadlock or resources conflict. At last, this paper analyzes the feasibility of this method.
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Propagation of crises in the virtual water trade network
Tamea, Stefania; Laio, Francesco; Ridolfi, Luca
2015-04-01
The international trade of agricultural goods is associated to the displacement of the water used to produce such goods and embedded in trade as a factor of production. Water virtually exchanged from producing to consuming countries, named virtual water, defines flows across an international network of 'virtual water trade' which enable the assessment of environmental forcings and implications of trade, such as global water savings or country dependencies on foreign water resources. Given the recent expansion of commodity (and virtual water) trade, in both displaced volumes and network structure, concerns have been raised about the exposure to crises of individuals and societies. In fact, if one country had to markedly decrease its export following a socio-economical or environmental crisis, such as a war or a drought, many -if not all- countries would be affected due to a cascade effect within the trade network. The present contribution proposes a mechanistic model describing the propagation of a local crisis into the virtual water trade network, accounting for the network structure and the virtual water balance of all countries. The model, built on data-based assumptions, is tested on the real case study of the Argentinean crisis in 2008-09, when the internal agricultural production (measured as virtual water volume) decreased by 26% and the virtual water export of Argentina dropped accordingly. Crisis propagation and effects on the virtual water trade are correctly captured, showing the way forward to investigations of crises impact and country vulnerability based on the results of the model proposed.
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Application of virtual water trade theory in interregional grain ...
African Journals Online (AJOL)
Application of virtual water trade theory in interregional grain allocation and ... was calculated in 2008 based on virtual water and virtual water trade theories. ... The whole country saved about 3.05×1010m³ water resource as a result of the well ...
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Evolution of the global virtual water trade network.
Dalin, Carole; Konar, Megan; Hanasaki, Naota; Rinaldo, Andrea; Rodriguez-Iturbe, Ignacio
2012-04-17
Global freshwater resources are under increasing pressure from economic development, population growth, and climate change. The international trade of water-intensive products (e.g., agricultural commodities) or virtual water trade has been suggested as a way to save water globally. We focus on the virtual water trade network associated with international food trade built with annual trade data and annual modeled virtual water content. The evolution of this network from 1986 to 2007 is analyzed and linked to trade policies, socioeconomic circumstances, and agricultural efficiency. We find that the number of trade connections and the volume of water associated with global food trade more than doubled in 22 years. Despite this growth, constant organizational features were observed in the network. However, both regional and national virtual water trade patterns significantly changed. Indeed, Asia increased its virtual water imports by more than 170%, switching from North America to South America as its main partner, whereas North America oriented to a growing intraregional trade. A dramatic rise in China's virtual water imports is associated with its increased soy imports after a domestic policy shift in 2000. Significantly, this shift has led the global soy market to save water on a global scale, but it also relies on expanding soy production in Brazil, which contributes to deforestation in the Amazon. We find that the international food trade has led to enhanced savings in global water resources over time, indicating its growing efficiency in terms of global water use.
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WaterNet: The NASA Water Cycle Solutions Network
Houser, P. R.; Belvedere, D. R.; Pozzi, W. H.; Imam, B.; Schiffer, R.; Lawford, R.; Schlosser, C. A.; Gupta, H.; Welty, C.; Vorosmarty, C.; Matthews, D.
2007-12-01
Water is essential to life and directly impacts and constrains society's welfare, progress, and sustainable growth, and is continuously being transformed by climate change, erosion, pollution, and engineering practices. The water cycle is a critical resource for industry, agriculture, natural ecosystems, fisheries, aquaculture, hydroelectric power, recreation, and water supply, and is central to drought, flood, transportation-aviation, and disease hazards. It is therefore a national priority to use advancements in scientific observations and knowledge to develop solutions to the water challenges faced by society. NASA's unique role is to use its view from space to improve water and energy cycle monitoring and prediction. NASA has collected substantial water cycle information and knowledge that must be transitioned to develop solutions for all twelve National Priority Application (NPA) areas. NASA cannot achieve this goal alone -it must establish collaborations and interoperability with existing networks and nodes of research organizations, operational agencies, science communities, and private industry. Therefore, WaterNet: The NASA Water Cycle Solutions Network goal is to improve and optimize the sustained ability of water cycle researchers, stakeholders, organizations and networks to interact, identify, harness, and extend NASA research results to augment decision support tools and meet national needs. WaterNet is a catalyst for discovery and sharing of creative solutions to water problems. It serves as a creative, discovery process that is the entry-path for a research-to-solutions systems engineering NASA framework, with the end result to ultimately improve decision support.
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The Politics and Consequences of Virtual Water Export
Vos, J.; Boelens, R.A.; Jackson, P.; Spiess, W.E.L.; Sultana, F.
2016-01-01
Virtual water is the water used or contaminated to produce a good or a service. With the large increase of export of agricultural produce during the last decades the amount of virtual water export has grown as well. Increased water contamination and water extraction for export from relative dry
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Measuring scarce water saving from interregional virtual water flows in China
Zhao, X.; Li, Y. P.; Yang, H.; Liu, W. F.; Tillotson, M. R.; Guan, D.; Yi, Y.; Wang, H.
2018-05-01
Trade of commodities can lead to virtual water flows between trading partners. When commodities flow from regions of high water productivity to regions of low water productivity, the trade has the potential to generate water saving. However, this accounting of water saving does not account for the water scarcity status in different regions. It could be that the water saving generated from this trade occurs at the expense of the intensified water scarcity in the exporting region, and exerts limited effect on water stress alleviation in importing regions. In this paper, we propose an approach to measure the scarce water saving associated with virtual water trade (measuring in water withdrawal/use). The scarce water is quantified by multiplying the water use in production with the water stress index (WSI). We assessed the scarce water saving/loss through interprovincial trade within China using a multi-region input-output table from 2010. The results show that interprovincial trade resulted in 14.2 km3 of water loss without considering water stress, but only 0.4 km3 scarce water loss using the scarce water concept. Among the 435 total connections of virtual water flows, 254 connections contributed to 20.2 km3 of scarce water saving. Most of these connections are virtual water flows from provinces with lower WSI to that with higher WSI. Conversely, 175 connections contributed to 20.6 km3 of scarce water loss. The virtual water flow connections between Xinjiang and other provinces stood out as the biggest contributors, accounting for 66% of total scarce water loss. The results show the importance of assessing water savings generated from trade with consideration of both water scarcity status and water productivity across regions. Identifying key connections of scarce water saving is useful in guiding interregional economic restructuring towards water stress alleviation, a major goal of China’s sustainable development strategy.
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The role of scarcity in global virtual water flows
Lenzen, Manfred; Bhaduri, Anik; Moran, Daniel; Kanemoto, Keiichiro; Bekchanov, Maksud
2012-01-01
Recent analyses of the evolution and structure of trade in virtual water revealed that the number of trade connections and volume of virtual water trade have more than doubled over the past two decades, and that developed countries increasingly draw on the rest of the world to alleviate the pressure on their domestic water resources. Our work builds on these studies, but fills three important gaps in the research on global virtual water trade. First, we note that in previous studies virtual w...
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Entropy of Egypt's virtual water trade gravity field
Karakatsanis, Georgios; Bierbach, Sandra
2016-04-01
The study investigates the entropy of Egypt's virtual water trade gravity distribution, in order to provide a chart of Egypt's embodied water balance in agricultural trade, in relation to distances with its major counterparties. Moreover, our calculations on the amount of the embodied water traded between Egypt and each of its partners take place according to a combination of available data on the blue, green and grey water footprints as well as the Food and Agriculture Organization (FAO) database of traded amounts per crop type. A study on the virtual water trade gravity, enables us to enrich former related studies (Fracasso 2014; Fracasso, Sartori and Schiavo 2014) via examining Egypt's water supply dependence on the Nile River and if comparative advantages -purely from the side of water quantities- can be identified via recognizing which water footprint categories are particularly high. Additionally, this methodology can comprise -from a fundamental level- a guide for revealing the importance of water footprint types for Egypt's agricultural sector; hence, Egypt's potential comparative advantages, as far as quantitative water endowments are exclusively concerned (without consideration of water or crop prices). Although it is pointed out very correctly by various authors (Antonelli and Sartori 2014) that the virtual water trade concept does not incorporate many important aspects of water supply -such as heavy water price subsidizing- to be used accurately for the identification of comparative advantages, we consider that the purely quantitative examination can provide strong fundamental indications -especially for green and grey water footprints, which are hypothesized to be less sensitive to subsidizing. In overall, this effect can very well provide a primary indication on the organization of the global alimentation trade network (Yang et al. 2006). The gravity equation used contains water footprint data for the 15 top traded crops and the distances for Egypt
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Directory of Open Access Journals (Sweden)
J. M. Dabrowski
2009-10-01
Full Text Available The concept of virtual water encourages a country to view agricultural crops in terms of the amount of water required to produce those crops, with a view to implementing trading policies that promote the saving of scarce water resources. Recently, increased attention has focussed on partitioning the virtual water content of crops into green and blue water (derived from rainfall and irrigation, respectively as the latter has higher opportunity costs associated with its use and therefore impacts directly on scarcity. Maize is the most important crop traded within the SADC region. South Africa is the largest producer and exporter of maize, with the majority of its exports destined for other SADC countries. In comparison to other SADC countries, South Africa produces maize relatively efficiently, with a low virtual water content and a high green (868 m3 t−1 to blue (117 m3 t−1 water ratio. The blue water content is however higher than for maize produced in all other SADC countries, with the exception of Namibia (211 m3 t−1. Current trade patterns therefore result in a net expenditure of blue water (66×106 m3, almost all of which is exported by South Africa (65×106 m3. South Africa is one of the most water scarce countries in the region and analysis of virtual water flows indicates that current SADC maize trading patterns are influenced by national productivity as opposed to water scarcity. The virtual water content of maize was estimated for each of South Africa's nineteen Water Management Area's (WMA and used as a proxy to represent water use efficiency for maize production. The virtual water content varied widely across all of the WMAs, ranging from 360 m3 t−1 in the Ustutu Mhlatuze to 1000 m3 t−1 in the Limpopo. A comparison of the virtual water content and production of maize
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Water Footprint and Virtual Water Trade of Brazil
da Silva, Vicente de Paulo R.; de Oliveira, Sonaly D.; Hoekstra, Arjen Ysbert; Neto, Jose Dantas; Campos, João Hugo B.C.; Braga, Celia C.; Araújo, Lincoln Eloi; Oliveira Aleixo, Danilo; de Brito, Jose Ivaldo B.; de Souza, Marcio Dionisio; de Holanda, Romildo M.
2016-01-01
Freshwater scarcity has increased at an alarming rate worldwide; improved water management plays a vital role in increasing food production and security. This study aims to determine the water footprint of Brazil’s national food consumption, the virtual water flows associated with international
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Hoekstra, Arjen Ysbert; Hung, P.Q.
2005-01-01
The water that is used in the production process of a commodity is called the ‘virtual water’ contained in the commodity. International trade of commodities brings along international flows of virtual water. The objective of this paper is to quantify the volumes of virtual water flows between
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Virtual water exported from Californian agriculture
Nicholas, K. A.; Johansson, E. L.
2015-12-01
In an increasingly teleconnected world, international trade drives the exchange of virtual land and water as crops produced in one region are consumed in another. In theory, this can be an optimal use of scarce resources if crops are grown where they can most efficiently be produced. Several recent analyses examine the export of land and water from food production in developing countries where these resources may be more abundant. Here we focus on a developed region and examine the virtual export of land and water from California, the leading agricultural state in the US and the leading global producer of a wide range of fruit, nut, and other specialty crops. As the region faces a serious, ongoing drought, water use is being questioned, and water policy governance re-examined, particularly in the agricultural sector which uses over three-quarters of water appropriations in the state. We look at the blue water embodied in the most widely grown crops in California and use network analysis to examine the trading patterns for flows of virtual land and water. We identify the main crops and export partners representing the majority of water exports. Considered in the context of tradeoffs for land and water resources, we highlight the challenges and opportunities for food production systems to play a sustainable role in meeting human needs while protecting the life-support systems of the planet.
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Physical and virtual water transfers for regional water stress alleviation in China.
Zhao, Xu; Liu, Junguo; Liu, Qingying; Tillotson, Martin R; Guan, Dabo; Hubacek, Klaus
2015-01-27
Water can be redistributed through, in physical terms, water transfer projects and virtually, embodied water for the production of traded products. Here, we explore whether such water redistributions can help mitigate water stress in China. This study, for the first time to our knowledge, both compiles a full inventory for physical water transfers at a provincial level and maps virtual water flows between Chinese provinces in 2007 and 2030. Our results show that, at the national level, physical water flows because of the major water transfer projects amounted to 4.5% of national water supply, whereas virtual water flows accounted for 35% (varies between 11% and 65% at the provincial level) in 2007. Furthermore, our analysis shows that both physical and virtual water flows do not play a major role in mitigating water stress in the water-receiving regions but exacerbate water stress for the water-exporting regions of China. Future water stress in the main water-exporting provinces is likely to increase further based on our analysis of the historical trajectory of the major governing socioeconomic and technical factors and the full implementation of policy initiatives relating to water use and economic development. Improving water use efficiency is key to mitigating water stress, but the efficiency gains will be largely offset by the water demand increase caused by continued economic development. We conclude that much greater attention needs to be paid to water demand management rather than the current focus on supply-oriented management.
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The Virtual Water Transactions Promote Environmental Justice?
Directory of Open Access Journals (Sweden)
Thaís Dalla Corte
2016-12-01
Full Text Available As natural water, virtual water is essential for the dynamics of life. It, that correspond to the total volume of fresh water used in the production process in one place and that was incorporated into the final goods, is a calculation that can contribute to human access to water be assured in sufficient quantities for a dignified life. Therefore, the objective of this research is, through the hypothetical-deductive method of approach, evaluate virtual water transfers from the perspective of environmental justice in a globalized world in the Anthropocene.
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Kasperiuniene, Judita; Zydziunaite, Vilma; Eriksson, Malin
2017-01-01
This qualitative study explored the self-regulated learning (SRL) of teachers and their students in virtual social spaces. The processes of SRL were analyzed from 24 semi-structured individual interviews with professors, instructors and their students from five Lithuanian universities. A core category stroking the net whale showed the process of…
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Analyses of impacts of China's international trade on its water resources and uses
Zhang, Z. Y.; Yang, H.; Shi, M. J.; Zehnder, A. J. B.; Abbaspour, K. C.
2011-04-01
This study provides an insight into the impact of China's international trade of goods and services on its water resources and uses. Virtual water flows associated with China's international trade are quantified in an input-output framework. The analysis is scaled down to the sectoral and provincial levels to trace the origins and destinations of virtual water flows associated with the international trade. The results reveal that China is a net virtual water exporter of 4.7 × 1010 m3 year-1, accounting for 2.1% of its total water resources and 8.9% of the total water use. Water scarce regions tend to have higher percentages of virtual water export relative to their water resources and water uses. In the water scarce Huang-Huai-Hai region, the net virtual water export accounts for 7.9% of the region's water resources and 11.2% of its water uses. For individual sectors, major net virtual water exporters are those where agriculture provides raw materials in the initial process of the production chain and/or pollution intensity is high. The results suggest that China's economic gains from being a world "manufacture factory" have come at a high cost to its water resources and through pollution to its environment.
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Virtual versus real water transfers within China
Ma, Jing; Hoekstra, Arjen Y; Wang, Hao; Chapagain, Ashok K; Wang, Dangxian
2005-01-01
North China faces severe water scarcity—more than 40% of the annual renewable water resources are abstracted for human use. Nevertheless, nearly 10% of the water used in agriculture is employed in producing food exported to south China. To compensate for this ‘virtual water flow’ and to reduce water scarcity in the north, the huge south–north Water Transfer Project is currently being implemented. This paradox—the transfer of huge volumes of water from the water-rich south to the water-poor north versus transfer of substantial volumes of food from the food-sufficient north to the food-deficit south—is receiving increased attention, but the research in this field has not yet reached further than rough estimation and qualitative description. The aim of this paper is to review and quantify the volumes of virtual water flows between the regions in China and to put them in the context of water availability per region. The analysis shows that north China annually exports about 52 billion m3 of water in virtual form to south China, which is more than the maximum proposed water transfer volume along the three routes of the Water Transfer Project from south to north. PMID:16767828
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Virtual scarce water embodied in inter-provincial electricity transmission in China
International Nuclear Information System (INIS)
Zhang, Chao; Zhong, Lijin; Liang, Sai; Sanders, Kelly T.; Wang, Jiao; Xu, Ming
2017-01-01
Highlights: • Virtual water in inter-provincial electricity transmission in China is calculated. • A Water Stress Index is used to reflect relative scarcity of water consumption. • West Inner Mongolia is the largest exporter of scarce water. • Hebei, Beijing and Shandong are the three largest receivers of scarce water. - Abstract: Intra-national electricity transmission drives virtual water transfer from electricity production regions to electricity consumption regions. In China, the water-intensive thermoelectric power industry is expanding quickly in many water-scarce energy production hubs in northern and northwestern provinces. This study constructed a node-flow model of inter-provincial electricity transmission to investigate the virtual water and scarcity-adjusted virtual water (or virtual scarce water) embodied in the electricity transmission network. It is revealed that total inter-provincial virtual water transfer embodied in electricity transmission was 623 million m"3 in 2011, equivalent to 12.7% of the national total thermoelectric water consumption. The top three largest single virtual water flows are West Inner Mongolia-to-Beijing (44 million m"3), East Inner Mongolia-to-Liaoning (39 million m"3), and Guizhou-to-Guangdong (37 million m"3). If the actual volumes of consumptive water use are translated into scarcity-adjusted water consumption based on Water Stress Index, West Inner Mongolia (81 million m"3), Shanxi (63 million m"3) and Ningxia (30 million m"3) become the top three exporters of virtual scarce water. Many ongoing long-distance electricity transmission projects in China will enlarge the scale of scarce water outflows from northwestern regions and potentially increase their water stress.
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Virtuous and vicious virtual water trade with application to Italy.
Directory of Open Access Journals (Sweden)
Julia Anna Winter
Full Text Available The current trade of agricultural goods, with connections involving all continents, entails for global exchanges of "virtual" water, i.e. water used in the production process of alimentary products, but not contained within. Each trade link translates into a corresponding virtual water trade, allowing quantification of import and export fluxes of virtual water. The assessment of the virtual water import for a given nation, compared to the national consumption, could give an approximate idea of the country's reliance on external resources from the food and the water resources point of view. A descriptive approach to the understanding of a nation's degree of dependency from overseas food and water resources is first proposed, and indices of water trade virtuosity, as opposed to inefficiency, are devised. Such indices are based on the concepts of self-sufficiency and relative export, computed systematically on all products from the FAOSTAT database, taking Italy as the first case study. Analysis of time series of the self-sufficiency and relative export can demonstrate effects of market tendencies and influence water-related policies at the international level. The goal of this approach is highlighting incongruent terms in the virtual water balances by the viewpoint of single products. Specific products, which are here referred to as "swap products", are in fact identified as those that lead to inefficiencies in the virtual water balance due to their contemporaneously high import and export. The inefficiencies due to the exchanges of the same products between two nations are calculated in terms of virtual water volumes. Furthermore, the cases of swap products are investigated by computing two further indexes denoting the ratio of virtual water exchanged in the swap and the ratio of the economic values of the swapped products. The analysis of these figures can help examine the reasons behind the swap phenomenon in trade.
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Virtuous and vicious virtual water trade with application to Italy.
Winter, Julia Anna; Allamano, Paola; Claps, Pierluigi
2014-01-01
The current trade of agricultural goods, with connections involving all continents, entails for global exchanges of "virtual" water, i.e. water used in the production process of alimentary products, but not contained within. Each trade link translates into a corresponding virtual water trade, allowing quantification of import and export fluxes of virtual water. The assessment of the virtual water import for a given nation, compared to the national consumption, could give an approximate idea of the country's reliance on external resources from the food and the water resources point of view. A descriptive approach to the understanding of a nation's degree of dependency from overseas food and water resources is first proposed, and indices of water trade virtuosity, as opposed to inefficiency, are devised. Such indices are based on the concepts of self-sufficiency and relative export, computed systematically on all products from the FAOSTAT database, taking Italy as the first case study. Analysis of time series of the self-sufficiency and relative export can demonstrate effects of market tendencies and influence water-related policies at the international level. The goal of this approach is highlighting incongruent terms in the virtual water balances by the viewpoint of single products. Specific products, which are here referred to as "swap products", are in fact identified as those that lead to inefficiencies in the virtual water balance due to their contemporaneously high import and export. The inefficiencies due to the exchanges of the same products between two nations are calculated in terms of virtual water volumes. Furthermore, the cases of swap products are investigated by computing two further indexes denoting the ratio of virtual water exchanged in the swap and the ratio of the economic values of the swapped products. The analysis of these figures can help examine the reasons behind the swap phenomenon in trade.
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Modeling of water treatment plant using timed continuous Petri nets
Nurul Fuady Adhalia, H.; Subiono, Adzkiya, Dieky
2017-08-01
Petri nets represent graphically certain conditions and rules. In this paper, we construct a model of the Water Treatment Plant (WTP) using timed continuous Petri nets. Specifically, we consider that (1) the water pump always active and (2) the water source is always available. After obtaining the model, the flow through the transitions and token conservation laws are calculated.
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Virtual water embodied in international trade of soybean
DEFF Research Database (Denmark)
Caro, Dario; Thomsen, Marianne
This study focuses on hidden water flows embodied in the international trade of soybean. The virtual water content embedded in soybean imported and exported by 174 countries during the period 2000-2013 is estimated.......This study focuses on hidden water flows embodied in the international trade of soybean. The virtual water content embedded in soybean imported and exported by 174 countries during the period 2000-2013 is estimated....
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Today's virtual water consumption and trade under future water scarcity
International Nuclear Information System (INIS)
Orlowsky, B; Gudmundsson, L; Seneviratne, Sonia I; Hoekstra, A Y
2014-01-01
The populations of most nations consume products of both domestic and foreign origin, importing together with the products the water which is expended abroad for their production (termed ‘virtual water’). Therefore, any investigation of the sustainability of present-day water consumption under future climate change needs to consider the effects of potentially reduced water availability both on domestic water resources and on the trades of virtual water. Here we use combinations of Global Climate and Global Impact Models from the ISI–MIP ensemble to derive patterns of future water availability under the RCP2.6 and RCP8.5 greenhouse gas (GHG) concentrations scenarios. We assess the effects of reduced water availability in these scenarios on national water consumptions and virtual water trades through a simple accounting scheme based on the water footprint concept. We thereby identify countries where the water footprint within the country area is reduced due to a reduced within-area water availability, most prominently in the Mediterranean and some African countries. National water consumption in countries such as Russia, which are non-water scarce by themselves, can be affected through reduced imports from water scarce countries. We find overall stronger effects of the higher GHG concentrations scenario, although the model range of climate projections for single GHG concentrations scenarios is in itself larger than the differences induced by the GHG concentrations scenarios. Our results highlight that, for both investigated GHG concentration scenarios, the current water consumption and virtual water trades cannot be sustained into the future due to the projected patterns of reduced water availability. (letter)
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Ecological network analysis for a virtual water network.
Fang, Delin; Chen, Bin
2015-06-02
The notions of virtual water flows provide important indicators to manifest the water consumption and allocation between different sectors via product transactions. However, the configuration of virtual water network (VWN) still needs further investigation to identify the water interdependency among different sectors as well as the network efficiency and stability in a socio-economic system. Ecological network analysis is chosen as a useful tool to examine the structure and function of VWN and the interactions among its sectors. A balance analysis of efficiency and redundancy is also conducted to describe the robustness (RVWN) of VWN. Then, network control analysis and network utility analysis are performed to investigate the dominant sectors and pathways for virtual water circulation and the mutual relationships between pairwise sectors. A case study of the Heihe River Basin in China shows that the balance between efficiency and redundancy is situated on the left side of the robustness curve with less efficiency and higher redundancy. The forestation, herding and fishing sectors and industrial sectors are found to be the main controllers. The network tends to be more mutualistic and synergic, though some competitive relationships that weaken the virtual water circulation still exist.
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Zhuo, La; Mekonnen, Mesfin M; Hoekstra, Arjen Y
2016-09-01
The study assesses green and blue water footprints (WFs) and virtual water (VW) trade in China under alternative scenarios for 2030 and 2050, with a focus on crop production, consumption and trade. We consider five driving factors of change: climate, harvested crop area, technology, diet, and population. Four scenarios (S1-S4) are constructed by making use of three of IPCC's shared socio-economic pathways (SSP1-SSP3) and two of IPCC's representative concentration pathways (RCP 2.6 and RCP 8.5) and taking 2005 as the baseline year. Results show that, across the four scenarios and for most crops, the green and blue WFs per tonne will decrease compared to the baseline year, due to the projected crop yield increase, which is driven by the higher precipitation and CO2 concentration under the two RCPs and the foreseen uptake of better technology. The WF per capita related to food consumption decreases in all scenarios. Changing to the less-meat diet can generate a reduction in the WF of food consumption of 44% by 2050. In all scenarios, as a result of the projected increase in crop yields and thus overall growth in crop production, China will reverse its role from net VW importer to net VW exporter. However, China will remain a big net VW importer related to soybean, which accounts for 5% of the WF of Chinese food consumption (in S1) by 2050. All scenarios show that China could attain a high degree of food self-sufficiency while simultaneously reducing water consumption in agriculture. However, the premise of realizing the presented scenarios is smart water and cropland management, effective and coherent policies on water, agriculture and infrastructure, and, as in scenario S1, a shift to a diet containing less meat. Copyright © 2016 Elsevier Ltd. All rights reserved.
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Urban water metabolism efficiency assessment: integrated analysis of available and virtual water.
Huang, Chu-Long; Vause, Jonathan; Ma, Hwong-Wen; Yu, Chang-Ping
2013-05-01
Resolving the complex environmental problems of water pollution and shortage which occur during urbanization requires the systematic assessment of urban water metabolism efficiency (WME). While previous research has tended to focus on either available or virtual water metabolism, here we argue that the systematic problems arising during urbanization require an integrated assessment of available and virtual WME, using an indicator system based on material flow analysis (MFA) results. Future research should focus on the following areas: 1) analysis of available and virtual water flow patterns and processes through urban districts in different urbanization phases in years with varying amounts of rainfall, and their environmental effects; 2) based on the optimization of social, economic and environmental benefits, establishment of an indicator system for urban WME assessment using MFA results; 3) integrated assessment of available and virtual WME in districts with different urbanization levels, to facilitate study of the interactions between the natural and social water cycles; 4) analysis of mechanisms driving differences in WME between districts with different urbanization levels, and the selection of dominant social and economic driving indicators, especially those impacting water resource consumption. Combinations of these driving indicators could then be used to design efficient water resource metabolism solutions, and integrated management policies for reduced water consumption. Copyright © 2013 Elsevier B.V. All rights reserved.
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Virtual water trade of agri-food products: Evidence from italian-chinese relations.
Lamastra, Lucrezia; Miglietta, Pier Paolo; Toma, Pierluigi; De Leo, Federica; Massari, Stefania
2017-12-01
At global scale, the majority of world water withdrawal is for the agricultural sector, with differences among countries depending on the relevance of agri-food sector in the economy. Virtual water and water footprint could be useful to express the impact on the water resources of each production process and good with the objective to lead to a sustainable use of water at a global level. International trade could be connected to the virtual water flows, in fact through commodities importation, water poor countries can save their own water resources. The present paper focuses on the bilateral virtual water flows connected to the top ten agri-food products traded between Italy and China. Comparing the virtual water flow related to the top 10 agri-food products, the virtual water flow from Italy to China is bigger than the water flow in the opposite direction. Moreover, the composition of virtual water flows is different; Italy imports significant amounts of grey water from China, depending on the different environmental strategies adopted by the two selected countries. This difference could be also related to the fact that traded commodities are very different; the 91% of virtual water imported by Italy is connected to crops products, while the 95% of virtual water imported by China is related to the animal products. Considering national water saving and global water saving, appears that Italy imports virtual water from China while China exerts pressure on its water resources to supply the exports to Italy. This result at global scale implies a global water loss of 129.29millionm3 because, in general, the agri-food products are traded from the area with lower water productivity to the area with the higher water productivity. Copyright © 2017 Elsevier B.V. All rights reserved.
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Wang, Weiping; Gao, Lei; Liu, Pin; Hailu, Atakelty
2014-07-01
Northern China has been facing severe water scarcity as a result of vigorous economic growth, population expansion and changing lifestyles. A typical case is Shandong province whose water resources per capita is approximately only a sixth of the national average and a twentieth of the global average. It is useful to assess the implications of the province’s growth and trade patterns for water use and water conservation strategies. This study quantitatively analyses relationships between regional economic sectors and water use in Shandong using an input-output model for virtual water resources. The changes in key indicators for 1997-2007 are tracked and the effects of water-saving policies on these changes are examined. The results highlight the benefits of applying a virtual water trade analysis on a water-scarce region where water resources exhibit highly heterogeneous temporal and geographical distributions. The net export of virtual water in Shandong was initially large, but this declined over the years and the province has recently become a net importer. Between 1997 and 2002, water use in most sectors increased due to rapid urbanisation and industrialisation. Since then, water use in all Shandong economic sectors exhibit a downward trend despite continued increases in goods and services net exports, a trend which can be attributed to the vigorous implementation of water-saving policies and measures, especially water use quotas. Economic sectors consume water directly and indirectly and understanding the pattern of virtual water trade implied by sectoral relationships is important for managing water scarcity problems. This study fills the knowledge gap in the existing literature created by the lack of case studies that dynamically assess virtual water trade and analyse the effects of water-saving policies and measures. The study draws policy recommendations that are relevant for future water planning in Shandong and other regions in northern China.
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Spatial organization and drivers of the virtual water trade: a community-structure analysis
International Nuclear Information System (INIS)
D’Odorico, Paolo; Carr, Joel; Laio, Francesco; Ridolfi, Luca
2012-01-01
The trade of agricultural commodities can be associated with a virtual transfer of the local freshwater resources used for the production of these goods. Thus, trade of food products virtually transfers large amounts of water from areas of food production to far consumption regions, a process termed the ‘globalization of water’. We consider the (time-varying) community structure of the virtual water network for the years 1986–2008. The communities are groups of countries with dense internal connections, while the connections are sparser among different communities. Between 1986 and 2008, the ratio between virtual water flows within communities and the total global trade of virtual water has continuously increased, indicating the existence of well defined clusters of virtual water transfers. In some cases (e.g. Central and North America and Europe in recent years) the virtual water communities correspond to geographically coherent regions, suggesting the occurrence of an ongoing process of regionalization of water resources. However, most communities also include countries located on different ‘sides’ of the world. As such, geographic proximity only partly explains the community structure of virtual water trade. Similarly, the global distribution of people and wealth, whose effect on the virtual water trade is expressed through simple ‘gravity models’, is unable to explain the strength of virtual water communities observed in the past few decades. A gravity model based on the availability of and demand for virtual water in different countries has higher explanatory power, but the drivers of the virtual water fluxes are yet to be adequately identified. (letter)
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Shang Hai-Yang
2015-01-01
The scarcity of water is the key factor which restricted the growth of social-economy. The virtual water theory provides a new way to solve the problem of water scarcity. In this thesis, we have calculated the virtual water consumption of each household grouped by income in the cities of Gansu in 1992-2005 after introduced the virtual water theory and calculations briefly. Then we advanced the indicator of virtual water per unit of consumption expenditure to analyze the efficiency of virtual ...
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Can virtual water 'trade' reduce water scarcity in semi-arid countries? The case of Spain
Garrido, Alberto; Novo, Paula; Rodriguez Casado, Roberto; Varela-Ortega, Consuelo
2009-01-01
Agricultural trade is by far the largest vehicle to ‘move’ water virtually around the world. Observing that most countries import and export water embedded in the exchanged products, the objective of this study is to assess the virtual water ‘trade’ in Spain for the period 1997-2006. We differentiate between the green and blue components of virtual water from a hydrological and economic perspective. The combination of spatial and time dimensions offers a unique empirical setting to determine ...
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The trade of virtual water: do property rights matter?
Xu, Ankai
2016-04-01
My paper examines the determinants of the virtual water trade - embodied in the trade of agriculture products - by estimating a structural gravity model. In particular, it tests the relationship between property rights and the export of water-intensive agricultural products based on water footprint data in Mekonnen and Hoekstra (2011, 2012). Using two different measures of property rights protection, I show that countries with weaker property rights have an apparent comparative advantage in the trade of water-intensive products. After controlling for the economic size, natural resource endowments, and possible effects of reverse causality, the trade flow of virtual water is negatively and significantly correlated with the property rights index of the exporting country. Holding other factors constant, one point increase in the property rights index of a country is associated with a 24% - 36% decrease in its virtual water export, whereas a 1% increase in the natural resource protection index of a country is associated with a 16% decrease in its virtual water export. This paper is the first empirical work that tests the relationship between property rights and trade of water-intensive products, offering a new perceptive in the debate of virtual water trade. The findings provide a possible explanation on the paradoxical evidence that some countries with scarce water resources export water-intensive products. The result is important not only in terms of its theoretical relevance, but also its policy implications. As prescribed by the model of trade and property rights, when countries with weaker property rights open to international trade, they are more likely to over-exploit and thus expedite the depletion of natural resources.
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Coarse-Grained Model for Water Involving a Virtual Site.
Deng, Mingsen; Shen, Hujun
2016-02-04
In this work, we propose a new coarse-grained (CG) model for water by combining the features of two popular CG water models (BMW and MARTINI models) as well as by adopting a topology similar to that of the TIP4P water model. In this CG model, a CG unit, representing four real water molecules, consists of a virtual site, two positively charged particles, and a van der Waals (vdW) interaction center. Distance constraint is applied to the bonds formed between the vdW interaction center and the positively charged particles. The virtual site, which carries a negative charge, is determined by the locations of the two positively charged particles and the vdW interaction center. For the new CG model of water, we coined the name "CAVS" (charge is attached to a virtual site) due to the involvment of the virtual site. After being tested in molecular dynamic (MD) simulations of bulk water at various time steps, under different temperatures and in different salt (NaCl) concentrations, the CAVS model offers encouraging predictions for some bulk properties of water (such as density, dielectric constant, etc.) when compared to experimental ones.
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Ainge, David J.
1996-01-01
A grade 6/7 class which constructed and explored three-dimensional shapes with the VREAM virtual reality (VR) development system program was compared with a grade 5/6/7 control group using card nets (diagrams which can be cut out/folded). Results indicated that VR had little impact on shape visualization and name writing, but it strongly enhanced…
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Virtual versus real water transfers within China
Ma, Jing; Hoekstra, Arjen Ysbert; wang, Hao; Chapagain, Ashok; Wang, Dangxian
2006-01-01
North China faces severe water scarcity—more than 40% of the annual renewable water resources are abstracted for human use. Nevertheless, nearly 10% of the water used in agriculture is employed in producing food exported to south China. To compensate for this ‘virtual water flow’ and to reduce water
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Uncovering regional disparity of China's water footprint and inter-provincial virtual water flows.
Dong, Huijuan; Geng, Yong; Fujita, Tsuyoshi; Fujii, Minoru; Hao, Dong; Yu, Xiaoman
2014-12-01
With rapid economic development in China, water crisis is becoming serious and may impede future sustainable development. The uneven distribution of water resources further aggravates such a problem. Under such a circumstance, the concepts of water footprint and virtual water have been proposed in order to respond water scarcity problems. This paper focuses on studying provincial disparity of China's water footprints and inter-provincial virtual water trade flows by adopting inter-regional input-output (IRIO) method. The results show that fast developing areas with larger economic scales such as Guangdong, Jiangsu, Shandong, Zhejiang, Shanghai and Xinjiang had the largest water footprints. The most developed and water scarce areas such as Shanghai, Beijing, Tianjin and Shandong intended to import virtual water, a rational choice for mitigating their water crisis. Xinjiang, Jiangsu, Heilongjiang, Inner Mongolia, Guangxi and Hunan, had the largest per GDP water intensities and were the main water import regions. Another key finding is that agriculture water footprint was the main part in water footprint composition and water export trade. On the basis of these findings, policy implications on agriculture geographical dispersion, consumption behavior changes, trade structure adjustment and water use efficiency improvement are further discussed. Copyright © 2014 Elsevier B.V. All rights reserved.
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Ye, Quanliang; Li, Yi; Zhuo, La; Zhang, Wenlong; Xiong, Wei; Wang, Chao; Wang, Peifang
2018-02-01
This study provides an innovative application of virtual water trade in the traditional allocation of physical water resources in water scarce regions. A multi-objective optimization model was developed to optimize the allocation of physical water and virtual water resources to different water users in Beijing, China, considering the trade-offs between economic benefit and environmental impacts of water consumption. Surface water, groundwater, transferred water and reclaimed water constituted the physical resource of water supply side, while virtual water flow associated with the trade of five major crops (barley, corn, rice, soy and wheat) and three livestock products (beef, pork and poultry) in agricultural sector (calculated by the trade quantities of products and their virtual water contents). Urban (daily activities and public facilities), industry, environment and agriculture (products growing) were considered in water demand side. As for the traditional allocation of physical water resources, the results showed that agriculture and urban were the two predominant water users (accounting 54% and 28%, respectively), while groundwater and surface water satisfied around 70% water demands of different users (accounting 36% and 34%, respectively). When considered the virtual water trade of eight agricultural products in water allocation procedure, the proportion of agricultural consumption decreased to 45% in total water demand, while the groundwater consumption decreased to 24% in total water supply. Virtual water trade overturned the traditional components of water supplied from different sources for agricultural consumption, and became the largest water source in Beijing. Additionally, it was also found that environmental demand took a similar percentage of water consumption in each water source. Reclaimed water was the main water source for industrial and environmental users. The results suggest that physical water resources would mainly satisfy the consumption
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Recent work on network application layer: MioNet, the virtual workplace for small businesses
Hesselink, Lambertus; Rizal, Dharmarus; Bjornson, Eric; Miller, Brian; Chan, Keith
2005-11-01
Small businesses must be extremely efficient and smartly leverage their resources, suppliers, and partners to successfully compete with larger firms. A successful small business requires a set of companies with interlocking business relationships that are dynamic and needs-based. There has been no software solution that creates a secure and flexible way to efficiently connect small business computer-based employees and partners. In this invited paper, we discuss MioNet, a secure and powerful data management platform which may provide millions of small businesses with a virtual workplace and help them to succeed.
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Ecological network analysis on global virtual water trade.
Yang, Zhifeng; Mao, Xufeng; Zhao, Xu; Chen, Bin
2012-02-07
Global water interdependencies are likely to increase with growing virtual water trade. To address the issues of the indirect effects of water trade through the global economic circulation, we use ecological network analysis (ENA) to shed insight into the complicated system interactions. A global model of virtual water flow among agriculture and livestock production trade in 1995-1999 is also built as the basis for network analysis. Control analysis is used to identify the quantitative control or dependency relations. The utility analysis provides more indicators for describing the mutual relationship between two regions/countries by imitating the interactions in the ecosystem and distinguishes the beneficiary and the contributor of virtual water trade system. Results show control and utility relations can well depict the mutual relation in trade system, and direct observable relations differ from integral ones with indirect interactions considered. This paper offers a new way to depict the interrelations between trade components and can serve as a meaningful start as we continue to use ENA in providing more valuable implications for freshwater study on a global scale.
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UV sensitivity of planktonic net community production in ocean surface waters
Regaudie-de-Gioux, Aurore; Agustí, Susana; Duarte, Carlos M.
2014-05-01
The net plankton community metabolism of oceanic surface waters is particularly important as it more directly affects the partial pressure of CO2 in surface waters and thus the air-sea fluxes of CO2. Plankton communities in surface waters are exposed to high irradiance that includes significant ultraviolet blue (UVB, 280-315 nm) radiation. UVB radiation affects both photosynthetic and respiration rates, increase plankton mortality rates, and other metabolic and chemical processes. Here we test the sensitivity of net community production (NCP) to UVB of planktonic communities in surface waters across contrasting regions of the ocean. We observed here that UVB radiation affects net plankton community production at the ocean surface, imposing a shift in NCP by, on average, 50% relative to the values measured when excluding partly UVB. Our results show that under full solar radiation, the metabolic balance shows the prevalence of net heterotrophic community production. The demonstration of an important effect of UVB radiation on NCP in surface waters presented here is of particular relevance in relation to the increased UVB radiation derived from the erosion of the stratospheric ozone layer. Our results encourage design future research to further our understanding of UVB effects on the metabolic balance of plankton communities.
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Directory of Open Access Journals (Sweden)
Dennis Wichelns
2015-10-01
Full Text Available The notions of virtual water and water footprints were introduced originally to bring attention to the large amounts of water required to produce crops and livestock. Recently, several authors have begun applying those notions in efforts to describe efficiency, equity, and the sustainability of resources and production activities. In this paper, I describe why the notions of virtual water and water footprints are not appropriate for analysing issues pertaining to those topics. Both notions lack a supporting conceptual framework and they contain too little information to enhance understanding of important policy issues. Neither notion accounts for the opportunity cost or scarcity value of water in any setting, or the impacts of water availability and use on livelihoods. In addition, countries trade in goods and services – not in crop and livestock water requirements. Thus, the notions of virtual water and water footprints cannot provide helpful insight regarding the sustainability of water use, economic efficiency, or social equity. Gaining such insight requires the application of legitimate conceptual frameworks, representing a broad range of perspectives from the physical and social sciences, with due consideration of dynamics, uncertainty, and the impacts of policy choices on livelihoods and natural resources.
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Temporal dynamics of blue and green virtual water trade networks
Konar, M.; Dalin, C.; Hanasaki, N.; Rinaldo, A.; Rodriguez-Iturbe, I.
2012-12-01
Global food security increasingly relies on the trade of food commodities. Freshwater resources are essential to agricultural production and are thus embodied in the trade of food commodities, referred to as "virtual water trade." Agricultural production predominantly relies on rainwater (i.e., "green water"), though irrigation (i.e., "blue water") does play an important role. These different sources of water have distinctly different opportunity costs, which may be reflected in the way these resources are traded. Thus, the temporal dynamics of the virtual water trade networks from these distinct water sources require characterization. We find that 42 × 109 m3 blue and 310 × 109 m3 green water was traded in 1986, growing to 78 × 109 m3 blue and 594 × 109 m3 green water traded in 2008. Three nations dominate the export of green water resources: the USA, Argentina, and Brazil. As a country increases its export trade partners it tends to export relatively more blue water. However, as a country increases its import trade partners it does not preferentially import water from a specific source. The amount of virtual water that a country imports by increasing its import trade partners has been decreasing over time, with the exception of the soy trade. Both blue and green virtual water networks are efficient: 119 × 109 m3 blue and 105 × 109 m3 green water were saved in 2008. Importantly, trade has been increasingly saving water over time, due to the intensification of crop trade on more water-efficient links.
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Effects of virtual water flow on regional water resources stress: A case study of grain in China.
Sun, Shikun; Wang, Yubao; Engel, Bernie A; Wu, Pute
2016-04-15
Scarcity of water resources is one of the major challenges in the world, particularly for the main water consumer, agriculture. Virtual water flow (VWF) promotes water redistribution geographically and provides a new solution for resolving regional water shortage and improving water use efficiency in the world. Virtual water transfer among regions will have a significant influence on the water systems in both grain export and import regions. In order to assess the impacts of VWF related grain transfer on regional water resources conditions, the study takes mainland China as study area for a comprehensive evaluation of virtual water flow on regional water resources stress. Results show that Northeast China and Huang-Huai-Hai region are the major grain production regions as well as the major virtual water export regions. National water savings related to grain VWF was about 58Gm(3), with 48Gm(3) blue water and 10Gm(3) green water. VWF changes the original water distribution and has a significant effect on water resources in both virtual water import and export regions. Grain VWF significantly increased water stress in grain export regions and alleviated water stress in grain import regions. Water stress index (WSI) of Heilongjiang and Inner Mongolia has been increased by 138% and 129% due to grain export. Stress from water shortages is generally severe in export regions, and issues with the sustainability of grain production and VWF pattern are worthy of further exploration. Copyright © 2016 Elsevier B.V. All rights reserved.
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Global effects of local food-production crises: a virtual water perspective.
Tamea, Stefania; Laio, Francesco; Ridolfi, Luca
2016-01-25
By importing food and agricultural goods, countries cope with the heterogeneous global water distribution and often rely on water resources available abroad. The virtual displacement of the water used to produce such goods (known as virtual water) connects together, in a global water system, all countries participating to the international trade network. Local food-production crises, having social, economic or environmental origin, propagate in this network, modifying the virtual water trade and perturbing local and global food availability, quantified in terms of virtual water. We analyze here the possible effects of local crises by developing a new propagation model, parsimonious but grounded on data-based and statistically-verified assumptions, whose effectiveness is proved on the Argentinean crisis in 2008-09. The model serves as the basis to propose indicators of crisis impact and country vulnerability to external food-production crises, which highlight that countries with largest water resources have the highest impact on the international trade, and that not only water-scarce but also wealthy and globalized countries are among the most vulnerable to external crises. The temporal analysis reveals that global average vulnerability has increased over time and that stronger effects of crises are now found in countries with low food (and water) availability.
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Directory of Open Access Journals (Sweden)
Roberto Luiz do Carmo
2007-12-01
Full Text Available Recentemente, a valoração econômica da água tem sido discutida no cenário político brasileiro. Faz parte dessa discussão a incorporação da água nos produtos que circulam no mercado, especialmente através de commodities, utilizando o conceito de "água virtual". Este trabalho avalia o impacto da utilização do conceito de água virtual no cenário brasileiro, ao mesmo tempo em que discute as decorrências dessa exportação.The economic valuation of water has recently been discussed in the Brazilian political scenario. Incorporation of water in trade and commerce, especially in commodities is part of the proposed discussion , using the "virtual water" concept. In this article we search for the impact that the utilization of the "virtual water" concept may have in the Brazilian scenario and discuss, at the same time, the consequences of this exportation.
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Design of virtual SCADA simulation system for pressurized water reactor
International Nuclear Information System (INIS)
Wijaksono, Umar; Abdullah, Ade Gafar; Hakim, Dadang Lukman
2016-01-01
The Virtual SCADA system is a software-based Human-Machine Interface that can visualize the process of a plant. This paper described the results of the virtual SCADA system design that aims to recognize the principle of the Nuclear Power Plant type Pressurized Water Reactor. This simulation uses technical data of the Nuclear Power Plant Unit Olkiluoto 3 in Finland. This device was developed using Wonderware Intouch, which is equipped with manual books for each component, animation links, alarm systems, real time and historical trending, and security system. The results showed that in general this device can demonstrate clearly the principles of energy flow and energy conversion processes in Pressurized Water Reactors. This virtual SCADA simulation system can be used as instructional media to recognize the principle of Pressurized Water Reactor
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Design of virtual SCADA simulation system for pressurized water reactor
Energy Technology Data Exchange (ETDEWEB)
Wijaksono, Umar, E-mail: umar.wijaksono@student.upi.edu; Abdullah, Ade Gafar; Hakim, Dadang Lukman [Electrical Power System Research Group, Department of Electrical Engineering Education, Jl. Dr. Setiabudi No. 207 Bandung, Indonesia 40154 (Indonesia)
2016-02-08
The Virtual SCADA system is a software-based Human-Machine Interface that can visualize the process of a plant. This paper described the results of the virtual SCADA system design that aims to recognize the principle of the Nuclear Power Plant type Pressurized Water Reactor. This simulation uses technical data of the Nuclear Power Plant Unit Olkiluoto 3 in Finland. This device was developed using Wonderware Intouch, which is equipped with manual books for each component, animation links, alarm systems, real time and historical trending, and security system. The results showed that in general this device can demonstrate clearly the principles of energy flow and energy conversion processes in Pressurized Water Reactors. This virtual SCADA simulation system can be used as instructional media to recognize the principle of Pressurized Water Reactor.
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'Virtual Water' - Real People: Useful Concept or Prescriptive Tool?
Warner, J.F.; Johnson, C.L.
2007-01-01
The 'virtual water' thesis is beginning to take centre stage in the water security global discourse. From its origins as a conceptual tool for countering the gloomy Malthusian ('water scarcity leads to water wars') argument, it is now increasingly seen as a serious prescriptive tool for the
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Darzi-Naftchali, Abdullah; Karandish, Fatemeh
2017-12-01
Sustainable utilization of blue water resources under climate change is of great significance especially for producing high water-consuming crops in water-scarce regions. Based on the virtual water concept, we carried out a comprehensive field-modeling research to find the optimal agricultural practices regarding rice blue water consumption under prospective climate change. The DSSAT-CERES-Rice model was used in combination with 20 GCMs under three Representative Concentration Pathways of low (RCP2.6), intermediate (RCP4.6), and very high (RCP8.5) greenhouse concentrations to predict rice yield and water requirement and related virtual water and economic return for the base and future periods. The crop model was calibrated and validated based on the 2-year field data obtained from consolidated paddy fields of the Sari Agricultural Sciences and Natural Resources University during 2011 and 2012 rice cropping cycles. Climate change imposes an increase of 0.02-0.04 °C in air temperature which consequently shifts rice growing seasons to winter season, and shorten the length of rice physiological maturity period by 2-15 days. While rice virtual water reduces by 0.1-20.6% during 2011-2070, reduced rice yield by 3.8-22.6% over the late twenty-first century results in a considerable increase in rice virtual water. By increasing the contribution of green water in supplying crop water requirement, earlier cropping could diminish blue water consumption for rice production in the region while cultivation postponement increases irrigation water requirement by 2-195 m3 ha-1. Forty days delay in rice cultivation in future will result in 29.9-40.6% yield reduction and 43.9-60% increase in rice virtual water under different scenarios. Earlier cropping during the 2011-2040 and 2041-2070 periods would increase water productivity, unit value of water, and economic value of blue water compared to the base period. Based on the results, management of rice cultivation calendar is a
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Risk classification and uncertainty propagation for virtual water distribution systems
International Nuclear Information System (INIS)
Torres, Jacob M.; Brumbelow, Kelly; Guikema, Seth D.
2009-01-01
While the secrecy of real water distribution system data is crucial, it poses difficulty for research as results cannot be publicized. This data includes topological layouts of pipe networks, pump operation schedules, and water demands. Therefore, a library of virtual water distribution systems can be an important research tool for comparative development of analytical methods. A virtual city, 'Micropolis', has been developed, including a comprehensive water distribution system, as a first entry into such a library. This virtual city of 5000 residents is fully described in both geographic information systems (GIS) and EPANet hydraulic model frameworks. A risk classification scheme and Monte Carlo analysis are employed for an attempted water supply contamination attack. Model inputs to be considered include uncertainties in: daily water demand, seasonal demand, initial storage tank levels, the time of day a contamination event is initiated, duration of contamination event, and contaminant quantity. Findings show that reasonable uncertainties in model inputs produce high variability in exposure levels. It is also shown that exposure level distributions experience noticeable sensitivities to population clusters within the contaminant spread area. High uncertainties in exposure patterns lead to greater resources needed for more effective mitigation strategies.
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Virtual Crop Water Export Analysis: The Case of Greece at River Basin District Level
Directory of Open Access Journals (Sweden)
Nikolaos Mellios
2018-05-01
Full Text Available An analysis of virtual crop water export through international trade is conducted for Greece, downscaled to the River Basin District (RBD level, in order to identify critical “hotspots” of localized water shortage in the country. A computable general equilibrium model (MAGNET was used to obtain the export shares of crops and associated irrigation water was calculated for all major crops in Greece. A distinction between virtual crop water locally consumed and traded internationally was made for all Greek RBDs. Cotton was identified as a large water consumer and virtual water exporter, while GR08 and GR10 were identified as the RBDs mostly impacted. The value of virtual water exported was calculated for all crop types and fruits and vegetables were identified as the crop most beneficial, since they consume the least water for the obtained value.
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Transfer of Virtual Water of Woody Forest Products from China
Directory of Open Access Journals (Sweden)
Kaisheng Luo
2018-02-01
Full Text Available Global freshwater resources are under increasing pressure. It is reported that international trade of water-intensive products (the so-called virtual water trade can be used to ease global water pressure. In spite of the significant amount of international trade of woody forest products, virtual water of woody forest products (VWWFP and the corresponding international trade are largely ignored. However, virtual water research has progressed steadily. This study maps VWWFP and statistically analyzes China’s official data for the period 1993–2014. The results show a rapid increase in the trend of VWWFP flow from China, reaching 7.61 × 1012 m3 or 3.48 times annual virtual water trade for agricultural products. The export and import volumes of China are respectively 1.27 × 1012 m3 and 6.34 × 1012 m3 for 1993–2014. China imported a total of 5.07 × 1012 m3 of VWWFP in 1993–2014 to lessen domestic water pressure, which is five times the annual water transfer via China’s South–North Water Transfer project. Asia and Europe account for the highest contribution (50.52% to China’s import. Other contributors include the Russian Federation (16.63%, Indonesia (13.45%, Canada (13.41%, the United States of America (9.60%, Brazil (7.23% and Malaysia (6.33%. China mainly exports VWWFP to Asia (47.68%, North America (23.24%, and Europe (20.01%. The countries which export the highest amount of VWWFP include the United States of America, Japan, Republic of Korea and Canada. Then the countries which import the highest amount of VWWFP include the Russian Federation, Canada, United States of America, and Brazil. The VWWFP flow study shows an obvious geographical distribution that is driven by proximity and traffic since transportation cost of woody forest products could be significant.
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Virtual Class Support at the Virtual Machine Level
DEFF Research Database (Denmark)
Nielsen, Anders Bach; Ernst, Erik
2009-01-01
This paper describes how virtual classes can be supported in a virtual machine. Main-stream virtual machines such as the Java Virtual Machine and the .NET platform dominate the world today, and many languages are being executed on these virtual machines even though their embodied design choices...... conflict with the design choices of the virtual machine. For instance, there is a non-trivial mismatch between the main-stream virtual machines mentioned above and dynamically typed languages. One language concept that creates an even greater mismatch is virtual classes, in particular because fully...... general support for virtual classes requires generation of new classes at run-time by mixin composition. Languages like CaesarJ and ObjectTeams can express virtual classes restricted to the subset that does not require run-time generation of classes, because of the restrictions imposed by the Java...
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Globalisation of water: opportunities and threats of virtual water trade
Chapagain, A.K.
2006-01-01
Where the river basin is generally seen as the appropriate unit for analyzing freshwater availability and use, it becomes increasingly important to put freshwater issues in a global context. The book analyses the opportunities and threats of international virtual water trade in the context of
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Hapsari, Trisnani D.; Jayanto, Bogi B.; Fitri, Aristi D. P.; Triarso, I.
2018-02-01
Lift net is one of the fishing gears that is used widely in the Morodemak coastal fishing port (PPP) for catching pelagic fish. The yield of fish captured by these fishing gear has high economic value, such as fish belt (Trichiurus sp), squids (Loligo sp) and anchovies (Stelophorus sp). The aims of this research were to determine the technical aspects of boat lift net and stationary lift net fishing gear in Morodemak Waters Demak Regency; to find out the financial aspect of those fishing gears and to analyze the financial feasibility by counting PP, NPV, IRR, and B/C ratio criteria. This research used case study method with descriptive analysis. The sampling method was purposive sampling with 22 fishermen as respondents. The result of the research showed that the average of boat lift net acceptance was Rp 388,580,000. The financial analysis of fisheries boat lift net with the result of NPV Rp 836,149,272, PP 2.44 years, IRR value 54%, and B/C ratio 1.73. The average of stationary lift net acceptance was Rp 27,750,000. The financial analysis lift net with the result of NPV Rp 37,937,601; PP 1.96 years, IRR value 86%, and B/C ratio 1.32. This research had a positive NPV value, B/C ratio >1, and IRR > discount rate (12 %). This study concluded that the fishery business of boat lift net and stationary lift net in Morodemak coastal fishing port (PPP) was worth running.
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Zhao, Xu; Yang, Hong; Yang, Zhifeng; Chen, Bin; Qin, Yan
2010-12-01
The virtual water strategy which advocates importing water intensive products and exporting products with low water intensity is gradually accepted as one of the options for solving water crisis in severely water scarce regions. However, if we count the virtual water embodied in imported products as the water saved for a region, we might overestimate the saving by including the virtual water that is later re-exported in association with the proceeded products made from the originally imported products. This problem can be avoided by accounting for the saved water through calculating water footprint (WF) in domestic final consumptive products. In this paper, an input-output analysis (IOA) based on the water footprint accounting framework is built to account for WF and virtual water trade of final consumptive products in the water stressed Haihe River basin in China for the year 1997, 2000, and 2002. The input-output transaction tables of the three years are constructed. The results show WF of 46.57, 44.52, and 42.71 billion m(3) for the three years, respectively. These volumes are higher than the water used directly in the corresponding years in the basin. A WF intensity (WFI) indicator is then used to assess if the economic activities in the basin are consistent with the virtual water strategy. The temporal change of the WFI is also decomposed by the index number analysis method. The results showed that the basin was silently importing virtual water through the trade of raw and processed food commodities under the background of the whole economic circulation.
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The Water Suitcase of Migrants: Assessing Virtual Water Fluxes Associated to Human Migration.
Metulini, Rodolfo; Tamea, Stefania; Laio, Francesco; Riccaboni, Massimo
2016-01-01
Disentangling the relations between human migrations and water resources is relevant for food security and trade policy in water-scarce countries. It is commonly believed that human migrations are beneficial to the water endowments of origin countries for reducing the pressure on local resources. We show here that such belief is over-simplistic. We reframe the problem by considering the international food trade and the corresponding virtual water fluxes, which quantify the water used for the production of traded agricultural commodities. By means of robust analytical tools, we show that migrants strengthen the commercial links between countries, triggering trade fluxes caused by food consumption habits persisting after migration. Thus migrants significantly increase the virtual water fluxes and the use of water in the countries of origin. The flux ascribable to each migrant, i.e. the "water suitcase", is found to have increased from 321 m3/y in 1990 to 1367 m3/y in 2010. A comparison with the water footprint of individuals shows that where the water suitcase exceeds the water footprint of inhabitants, migrations turn out to be detrimental to the water endowments of origin countries, challenging the common perception that migrations tend to relieve the pressure on the local (water) resources of origin countries.
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From water to energy. The virtual water content and water footprint of biofuel consumption in Spain
Energy Technology Data Exchange (ETDEWEB)
Elena, Galan-del-Castillo [Universitat Autonoma de Barcelona (Spain); Esther, Velazquez [Pablo de Olavide University, Department of Economics, Crta. Utrera, Km.1, 41013 Seville (Spain)
2010-03-15
Energy diversification and the use of renewable energy sources are key points in the European energy strategy. Biofuels are the most popular renewable resource option for the transport sector, and the European Union has established objectives that the Member States must adopt and implement. However, biofuel production at such a scale requires a considerable amount of water resources, and this water-energy nexus is rarely taken into account. This paper shows the strong nexus between water and energy in biofuel production and estimates the virtual water (VW) content and the water footprint (WF) from the raw material production that will be needed to reach the Spanish targets for biofuel consumption by 2010. The results show how the impact of such targets on the global and local water situation could be reduced through virtual water imports and, at the same time, how these imports could increase Spain's water and energy dependence. Hence, in order to manage water from an integral perspective of the territory, the inclusion of biofuel consumption objectives should go hand in hand with measures to reduce the demand of energy in the transport sector. (author)
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From water to energy: The virtual water content and water footprint of biofuel consumption in Spain
Energy Technology Data Exchange (ETDEWEB)
Galan-del-Castillo, Elena [Universitat Autonoma de Barcelona (Spain); Velazquez, Esther, E-mail: evelalo@upo.e [Pablo de Olavide University, Department of Economics, Crta. Utrera, Km.1, 41013 Seville (Spain)
2010-03-15
Energy diversification and the use of renewable energy sources are key points in the European energy strategy. Biofuels are the most popular renewable resource option for the transport sector, and the European Union has established objectives that the Member States must adopt and implement. However, biofuel production at such a scale requires a considerable amount of water resources, and this water-energy nexus is rarely taken into account. This paper shows the strong nexus between water and energy in biofuel production and estimates the virtual water (VW) content and the water footprint (WF) from the raw material production that will be needed to reach the Spanish targets for biofuel consumption by 2010. The results show how the impact of such targets on the global and local water situation could be reduced through virtual water imports and, at the same time, how these imports could increase Spain's water and energy dependence. Hence, in order to manage water from an integral perspective of the territory, the inclusion of biofuel consumption objectives should go hand in hand with measures to reduce the demand of energy in the transport sector.
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From water to energy. The virtual water content and water footprint of biofuel consumption in Spain
International Nuclear Information System (INIS)
Elena, Galan-del-Castillo; Esther, Velazquez
2010-01-01
Energy diversification and the use of renewable energy sources are key points in the European energy strategy. Biofuels are the most popular renewable resource option for the transport sector, and the European Union has established objectives that the Member States must adopt and implement. However, biofuel production at such a scale requires a considerable amount of water resources, and this water-energy nexus is rarely taken into account. This paper shows the strong nexus between water and energy in biofuel production and estimates the virtual water (VW) content and the water footprint (WF) from the raw material production that will be needed to reach the Spanish targets for biofuel consumption by 2010. The results show how the impact of such targets on the global and local water situation could be reduced through virtual water imports and, at the same time, how these imports could increase Spain's water and energy dependence. Hence, in order to manage water from an integral perspective of the territory, the inclusion of biofuel consumption objectives should go hand in hand with measures to reduce the demand of energy in the transport sector. (author)
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Drivers and Effects of Virtual Water Cycling
D'Odorico, P.
2016-12-01
The increasing global demand for farmland products by the growing and increasingly burgeoning human population is placing unprecedented pressure on the global agricultural system and its water resources. Many regions of the world that are not self-sufficient because of their chronic water scarcity or lack of suitable agricultural land strongly depend on the importation of agricultural commodities and associated embodied (or "virtual") water. International trade, however, may become unreliable when the supplies in the international food market are scarce. As a result, transboundary investments in agricultural land have become a priority for a number of governments and corporations that are trying to expand their agricultural production while securing good profits. This global "land rush" is often driven by the need for a secure access to water resources for agriculture. The globalization of water and land through trade and foreign land acquisitions is leading to a displacement of land use and a disconnection between human populations and the water resources they rely on. Despite the recognized importance of these phenomena in reshaping the patterns of water dependency through teleconnections between consumer behavior and production areas, their effect on global and regional food security, remains poorly quantified. New teleconnections are also emerging from the increasing water use for energy production. Competition in water use for food and energy security constitutes the core of an emerging debate that is generating new questions on the environmental, ethical, economic, and policy implications of human appropriation of water resources. This lecture will examine the ways societies virtually modify their access to water through trade and foreign land acquisitions to meet their growing food and energy needs.
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Souissi, Asma; Benalaya, Abdallah; Abdelkefi, Belhassen; Stambouli, Talel Ben Bechir; Ghezal, Lamia; Belaid, Rabeh; Naceur, Youssef; Oueslati, Marwa; Fekih, Saida; Benabdallah, Saker; Frija, Aymen
2013-01-01
Virtual water represents all freshwater used in the process of producing a commodity. In the case of agricultural products, many studies have focused on quantifying virtual water flows through international trade products. The concept of virtual water commercialization should be carefully studied as a potential solution for water scarcity, especially in countries facing risks of water shortage in a few years such as in Tunisia. The main idea of this paper is to optimize water u...
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Fat ViP MRI: Virtual Phantom Magnetic Resonance Imaging of water-fat systems.
Salvati, Roberto; Hitti, Eric; Bellanger, Jean-Jacques; Saint-Jalmes, Hervé; Gambarota, Giulio
2016-06-01
Virtual Phantom Magnetic Resonance Imaging (ViP MRI) is a method to generate reference signals on MR images, using external radiofrequency (RF) signals. The aim of this study was to assess the feasibility of ViP MRI to generate complex-data images of phantoms mimicking water-fat systems. Various numerical phantoms with a given fat fraction, T2* and field map were designed. The k-space of numerical phantoms was converted into RF signals to generate virtual phantoms. MRI experiments were performed at 4.7T using a multi-gradient-echo sequence on virtual and physical phantoms. The data acquisition of virtual and physical phantoms was simultaneous. Decomposition of the water and fat signals was performed using a complex-based water-fat separation algorithm. Overall, a good agreement was observed between the fat fraction, T2* and phase map values of the virtual and numerical phantoms. In particular, fat fractions of 10.5±0.1 (vs 10% of the numerical phantom), 20.3±0.1 (vs 20%) and 30.4±0.1 (vs 30%) were obtained in virtual phantoms. The ViP MRI method allows for generating imaging phantoms that i) mimic water-fat systems and ii) can be analyzed with water-fat separation algorithms based on complex data. Copyright © 2016 Elsevier Inc. All rights reserved.
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Zhuo, La; Mekonnen, Mesfin M.; Hoekstra, Arjen Y.
2015-04-01
China is facing water-related challenges, including an uneven distribution of water resources, both temporally and spatially, and an increasing competition over the limited water resources among different sectors. This issue has been widely researched and was finally included into the National Plan 2011 (the 2011 No. 1 Document by the State Council of China). However, there is still lack of information on how population growth and rapid urbanization have affected the water resources in China over the last decades. The current study aims at investigating (i) the intra-annual variation of green and blue water footprints (WFs) of crop production in China over the period 1978-2009 at a spatial resolution of 5 by 5 arc-minute; (ii) the yearly virtual water (VW) balances of 31 provinces within China, related water savings for the country, as well as the VW flows among eight economic regions resulting from inter-regional crop trade over the same period; and (iii) the development of the WF related to crop consumption by Chinese consumers. Results show that, over the period 1978-2009, the total WF related to crop production within China increased by only 4%), but regional changes were significant. From the 1980s to the 2000s, the shift of the cropping centre from the South to the North resulted in an increase of about 16% in the blue WF and 19% in the green WF in the North and a reduction of the blue and green WF in the South by 11% and 3%, respectively. China as a whole was a net virtual water importer related to crop trade, thus saving domestic water resources. China's inter-regional crop trade generated a blue water 'loss' annually by transferring crops from provinces with relatively low crop water productivity to provinces with relatively high productivity. Over the decades, the original VW flow from the South coastal region to the Northeast was reversed. Rice was the all-time dominant crop in the inter-regional VW flows (accounting for 34% in 2009), followed by wheat
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Martinez-Aldaya, Maite; Martínez-Santos, Pedro; Llamas, M. Ramón
2010-01-01
Water resource management is often a controversial issue in semiarid regions. Most water resources experts admit that water conflicts are not caused by the physical water scarcity but they are mainly due to inadequate water management. The virtual water concept (the volume of water used in the
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Mineralizing urban net-zero water treatment: Phase II field results and design recommendations
Net-zero water (NZW) systems, or water management systems achieving high recycling rates and low residuals generation so as to avoid water import and export, can also conserve energy used to heat and convey water, while economically restoring local eco-hydrology. However, design ...
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Chouchane, Hatem; Krol, Martinus S.; Hoekstra, Arjen Y.
2018-01-01
Growing water demands put increasing pressure on local water resources, especially in water-short countries. Virtual water trade can play a key role in filling the gap between local demand and supply of water-intensive commodities. This study aims to analyse the dynamics in virtual water trade of
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Characterization of the phantom material virtual water in high-energy photon and electron beams.
McEwen, M R; Niven, D
2006-04-01
The material Virtual Water has been characterized in photon and electron beams. Range-scaling factors and fluence correction factors were obtained, the latter with an uncertainty of around 0.2%. This level of uncertainty means that it may be possible to perform dosimetry in a solid phantom with an accuracy approaching that of measurements in water. Two formulations of Virtual Water were investigated with nominally the same elemental composition but differing densities. For photon beams neither formulation showed exact water equivalence-the water/Virtual Water dose ratio varied with the depth of measurement with a difference of over 1% at 10 cm depth. However, by using a density (range) scaling factor very good agreement (water and Virtual Water at all depths was obtained. In the case of electron beams a range-scaling factor was also required to match the shapes of the depth dose curves in water and Virtual Water. However, there remained a difference in the measured fluence in the two phantoms after this scaling factor had been applied. For measurements around the peak of the depth-dose curve and the reference depth this difference showed some small energy dependence but was in the range 0.1%-0.4%. Perturbation measurements have indicated that small slabs of material upstream of a detector have a small (<0.1% effect) on the chamber reading but material behind the detector can have a larger effect. This has consequences for the design of experiments and in the comparison of measurements and Monte Carlo-derived values.
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Sandbu, Marius
2014-01-01
An easy-to-follow guide with detailed step-by step-instructions on how to implement the different key components in NetScaler, with real-world examples and sample scenarios.If you are a Citrix or network administrator who needs to implement NetScaler in your virtual environment to gain an insight on its functionality, this book is ideal for you. A basic understanding of networking and familiarity with some of the different Citrix products such as XenApp or XenDesktop is a prerequisite.
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Vulnerability of countries to food-production crises propagating in the virtual water trade network
Tamea, S.; Laio, F.; Ridolfi, L.
2015-12-01
In recent years, the international trade of food and agricultural commodities has undergone a marked increase of exchanged volumes and an expansion of the trade network. This globalization of trade has both positive and negative effects, but the interconnectedness and external dependency of countries generate complex dynamics which are often difficult to understand and model. In this study we consider the volume of water used for the production of agricultural commodities, virtually exchanged among countries through commodity trade, i.e. the virtual water trade. Then, we set up a parsimonious mechanistic model describing the propagation, into the global trade network, of food-production crises generated locally by a social, economic or environmental event (such as war, economic crisis, drought, pest). The model, accounting for the network structure and the virtual water balance of all countries, bases on rules derived from observed virtual water flows and on data-based and statistically verified assumption. It is also tested on real case studies that prove its capability to capture the main features of crises propagation. The model is then employed as the basis for the development of an index of country vulnerability, measuring the exposure of countries to crises propagating in the virtual water trade network. Results of the analysis are discussed within the context of socio-economic and environmental conditions of countries, showing that not only water-scarce, but also wealthy and globalized countries, are among the most vulnerable to external crises. The temporal analysis for the period 1986-2011 reveals that the global average vulnerability has strongly increased over time, confirming the increased exposure of countries to external crises which may occur in the virtual water trade network.
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Can net photosynthesis and water relations provide a clue on the ...
African Journals Online (AJOL)
Net photosynthesis, sap flow density (SFD) and water use efficiency (WUE) were measured in a Quercus suber forest in north Tunisia in an attempt to explain the forest decline. In general, sap flow was positively related to light intensity and water loss, indicating that high light intensities can increase the SFD up to the ...
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CPN Tools-Assisted Simulation and Verification of Nested Petri Nets
Directory of Open Access Journals (Sweden)
L. W. Dworza´nski
2012-01-01
Full Text Available Nested Petri nets (NP-nets are an extension of Petri net formalism within the “netswithin-nets” approach, when tokens in a marking are Petri nets, which have an autonomous behavior and are synchronized with the system net. The formalism of NP-nets allows modeling multi-level multi-agent systems with dynamic structure in a natural way. Currently, there is no tool for supporting NP-nets simulation and analysis. The paper proposes the translation of NP-nets into Colored Petri nets and the use of CPN Tools as a virtual machine for NP-nets modeling, simulation and automatic verification.
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Spontaneous Recovery of Human Spatial Memory in a Virtual Water Maze
Luna, David; Martínez, Héctor
2015-01-01
The occurrence of spontaneous recovery in human spatial memory was assessed using a virtual environment. In Experiment 1, spatial memory was established by training participants to locate a hidden platform in a virtual water maze using a set of four distal landmarks. In Experiment 2, after learning about the location of a hidden platform, the…
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Directory of Open Access Journals (Sweden)
Richard R. Rushforth
2015-06-01
Full Text Available Water footprinting has revealed hydro-economic interdependencies between distant global geographies via trade, especially of agricultural and manufactured goods. However, for metropolitan areas, trade not only entails commodity flows at many scales from intra-municipal to global, but also substantial intra-metropolitan flows of the skilled labor that is essential to a city’s high-value economy. Virtual water flows between municipalities are directly relevant for municipal water supply policy and infrastructure investment because they quantify the hydro-economic dependency between neighboring municipalities. These municipalities share a physical water supply and also place demands on their neighbors’ water supplies by outsourcing labor and commodity production outside the municipal and water supply system boundary to the metropolitan area. Metropolitan area communities span dense urban cores to fringe agricultural towns, spanning a wide range of the US hydro-economy. This study quantifies water footprints and virtual water flows of the complete economy of the Phoenix Metropolitan Area’s municipalities. A novel approach utilized journey to work data to estimate virtual water flows embedded in labor. Commodities dominate virtual water flows at all scales of analysis, however labor is shown to be important for intra-metropolitan virtual water flows. This is the first detailed water footprint analysis of Phoenix, an important city in a water-scarce region. This study establishes a hydro-economic typology for communities to define several niche roles and decision making points of view. This study’s findings can be used to classify communities with respect to their relative roles, and to benchmark future improvements in water sustainability for all types of communities. More importantly, these findings motivate cooperative approaches to intra-metropolitan water supply policy that recognize the hydro-economic interdependence of these
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How water is different from energy and food?
Hanasaki, N.; Oki, T.; Yano, S.
2017-12-01
Although water is rarely traded over long distances by itself, the total weight of the water consumed to produce traded commodities exceeds the weight of any other commodity traded in the world. This concept is known as virtual water trade. Although space-/time-/commodity-based quantification has been conducted extensively, the underlying causes of this peculiar feature have thus far received little exploration. Here, we use estimates of water consumption from a global hydrological model and statistical data related to food trade to elucidate three facts that explain the fundamental nature of virtual water trade with respect to alleviating water scarcity. First, we quantitatively illustrate the unique position of water among commodities based on its unit price and quantity of sales. Water has an extremely low unit price, and a tremendous volume of water is consumed per person each day. Second, we show that rich but water-scarce countries tend to reduce local water consumption by importing virtual water. Third, we demonstrate that nations characterized by net virtual water exports have higher water resources and income per capita and that no countries fall below a certain threshold with respect to both GDP and water resources. These points suggest that the virtual water trade is explained by economic characteristics of water and that sustainable development depends on promoting the co-development of poverty alleviation and water resource development.
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UV sensitivity of planktonic net community production in ocean surface waters
Regaudie de Gioux, Aurore; Agustí, Susana; Duarte, Carlos M.
2014-01-01
The net plankton community metabolism of oceanic surface waters is particularly important as it more directly affects the partial pressure of CO2 in surface waters and thus the air-sea fluxes of CO2. Plankton communities in surface waters are exposed to high irradiance that includes significant ultraviolet blue (UVB, 280-315 nm) radiation. UVB radiation affects both photosynthetic and respiration rates, increase plankton mortality rates, and other metabolic and chemical processes. Here we tes...
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Jonker, L.; van der Zaag, P.; Gumbo, B.; Rockström, J.; Love, D.; Savenije, H. H. G.
2012-03-01
This paper reports the experience of a regional network of academic departments involved in water education that started as a project and evolved, over a period of 12 yr, into an independent network organisation. The paper pursues three objectives. First, it argues that it makes good sense to organise postgraduate education and research on water resources on a regional scale. This is because water has a transboundary dimension that poses delicate sharing questions, an approach that promotes a common understanding of what the real water-related issues are, results in future water specialists speaking a common (water) language, enhances mutual respect, and can thus be considered an investment in future peace. Second, it presents the WaterNet experience as an example that a regional approach can work and has an impact. Third, it draws three generalised lessons from the WaterNet experience. Lesson 1: For a regional capacity building network to be effective, it must have a legitimate ownership structure and a clear mandate. Lesson 2: Organising water-related training opportunities at a regional and transboundary scale makes sense - not only because knowledge resources are scattered, but also because the topic - water - has a regional and transboundary scope. Lesson 3: Jointly developing educational programmes by sharing expertise and resources requires intense intellectual management and sufficient financial means.
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Virtual Water and Food Security in Tunisia | IDRC - International ...
International Development Research Centre (IDRC) Digital Library (Canada)
... on the world grain market has social implications for Tunisia's small farmers and ... Thus, when a country exports an agricultural product, in effect it also exports ... Tunisia that incorporates the virtual water concept in a food security strategy.
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Horizontal ichthyoplankton tow-net system with unobstructed net opening
Nester, Robert T.
1987-01-01
The larval fish sampler described here consists of a modified bridle, frame, and net system with an obstruction-free net opening and is small enough for use on boats 10 m or less in length. The tow net features a square net frame attached to a 0.5-m-diameter cylinder-on-cone plankton net with a bridle designed to eliminate all obstructions forward of the net opening, significantly reducing currents and vibrations in the water directly preceding the net. This system was effective in collecting larvae representing more than 25 species of fish at sampling depths ranging from surface to 10 m and could easily be used at greater depths.
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MOOving around the Net: The Educational Potential of MOOs.
1996
The use of MOOs, multi-user simulated environments in education examined in three papers include: "MOOving around the Net: The Educational Potential of MOOs: A Point of View" (Daniel Ingvarson); "MOOing in a Foreign Language: How, Why and Who?" (Lonnie Turbee) and "MOOving around the Net: Real to Virtual and Back…
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Frisch, Noreen; Atherton, Pat; Borycki, Elizabeth; Mickelson, Grace; Cordeiro, Jennifer; Novak Lauscher, Helen; Black, Agnes
2014-02-21
Use of Web 2.0 and social media technologies has become a new area of research among health professionals. Much of this work has focused on the use of technologies for health self-management and the ways technologies support communication between care providers and consumers. This paper addresses a new use of technology in providing a platform for health professionals to support professional development, increase knowledge utilization, and promote formal/informal professional communication. Specifically, we report on factors necessary to attract and sustain health professionals' use of a network designed to increase nurses' interest in and use of health services research and to support knowledge utilization activities in British Columbia, Canada. "InspireNet", a virtual professional network for health professionals, is a living laboratory permitting documentation of when and how professionals take up Web 2.0 and social media. Ongoing evaluation documents our experiences in establishing, operating, and evaluating this network. Overall evaluation methods included (1) tracking website use, (2) conducting two member surveys, and (3) soliciting member feedback through focus groups and interviews with those who participated in electronic communities of practice (eCoPs) and other stakeholders. These data have been used to learn about the types of support that seem relevant to network growth. Network growth exceeded all expectations. Members engaged with varying aspects of the network's virtual technologies, such as teams of professionals sharing a common interest, research teams conducting their work, and instructional webinars open to network members. Members used wikis, blogs, and discussion groups to support professional work, as well as a members' database with contact information and areas of interest. The database is accessed approximately 10 times per day. InspireNet public blog posts are accessed roughly 500 times each. At the time of writing, 21 research teams
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To trade or not to trade: Link prediction in the virtual water network
Tuninetti, Marta; Tamea, Stefania; Laio, Francesco; Ridolfi, Luca
2017-12-01
In the international trade network, links express the (temporary) presence of a commercial exchange of goods between any two countries. Given the dynamical behaviour of the trade network, where links are created and dismissed every year, predicting the link activation/deactivation is an open research question. Through the international trade network of agricultural goods, water resources are 'virtually' transferred from the country of production to the country of consumption. We propose a novel methodology for link prediction applied to the network of virtual water trade. Starting from the assumption of having links between any two countries, we estimate the associated virtual water flows by means of a gravity-law model using country and link characteristics as drivers. We consider the links with estimated flows higher than 1000 m3/year as active links, while the others as non-active links. Flows traded along estimated active links are then re-estimated using a similar but differently-calibrated gravity-law model. We were able to correctly model 84% of the existing links and 93% of the non-existing links in year 2011. It is worth to note that the predicted active links carry 99% of the global virtual water flow; hence, missed links are mainly those where a minimum volume of virtual water is exchanged. Results indicate that, over the period from 1986 to 2011, population, geographical distances between countries, and agricultural efficiency (through fertilizers use) are the major factors driving the link activation and deactivation. As opposed to other (network-based) models for link prediction, the proposed method is able to reconstruct the network architecture without any prior knowledge of the network topology, using only the nodes and links attributes; it thus represents a general method that can be applied to other networks such as food or value trade networks.
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Analysis of intra-country virtual water trade strategy to alleviate water scarcity in Iran
Faramarzi, M.; Yang, H.; Mousavi, J.; Schulin, R.; Binder, C. R.; Abbaspour, K. C.
2010-08-01
Increasing water scarcity has posed a major constraint to sustain food production in many parts of the world. To study the situation at the regional level, we took Iran as an example and analyzed how an intra-country "virtual water trade strategy" (VWTS) may help improve cereal production as well as alleviate the water scarcity problem. This strategy calls, in part, for the adjustment of the structure of cropping pattern (ASCP) and interregional food trade where crop yield and crop water productivity as well as local economic and social conditions are taken into account. We constructed a systematic framework to assess ASCP at the provincial level under various driving forces and constraints. A mixed-integer, multi-objective, linear optimization model was developed and solved by linear programming. Data from 1990-2004 were used to account for yearly fluctuations of water availability and food production. Five scenarios were designed aimed at maximizing the national cereal production while meeting certain levels of wheat self-sufficiency under various water and land constraints in individual provinces. The results show that under the baseline scenario, which assumes a continuation of the existing water use and food policy at the national level, some ASCP scenarios could produce more wheat with less water. Based on different scenarios in ASCP, we calculated that 31% to 100% of the total wheat shortage in the deficit provinces could be supplied by the wheat surplus provinces. As a result, wheat deficit provinces would receive 3.5 billion m3 to 5.5 billion m3 of virtual water by importing wheat from surplus provinces.
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(Virtual) Water Flows Uphill toward Money.
Wang, Ranran; Hertwich, Edgar; Zimmerman, Julie B
2016-11-15
This study provides a more precise understanding of the main driving forces of anthropogenic water use across countries. The anthropogenic water use was distinguished as blue water (i.e., fresh surface and groundwater) and total water (i.e. blue + green water; green water is rainwater insofar as it does not become runoff) used for producing, consuming, exporting, and importing of primary and manufactured goods and services, measured on a per country and per capita basis. The population effect on national blue water consumption associated with producing and consuming was found to be bigger than what the commonly assumed unitary population elasticity indicates. Distinct from the homogeneous affluence-water relationships conventionally assumed, this study revealed varying and potentially opposite effects affluence can have depending on the water use account of interest (e.g., production-based or consumption-based, blue or green) and the income level. Affluence, not the availability of freshwater resources, was found to be the most critical driver of virtual water imports. And a more affluent lifestyle in high-income countries was still associated with greater blue water consumption. With each doubling of income, blue water embedded in the goods and services a nation consumed and imported on a per capita basis increased by 82% and 86%, respectively, across the 110 countries analyzed for 2007. In comparison to affluence, the varying per capita water consumption accounts across the nations were much less sensitive to food consumption patterns. Given its critical role for water, land, and energy use shown by this and previous studies, affluence should be taken as a critical factor in future studies to better understand and leverage the water-energy-food-land nexus.
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System and method for determining the net output torque from a waste heat recovery system
Tricaud, Christophe; Ernst, Timothy C.; Zigan, James A.
2016-12-13
The disclosure provides a waste heat recovery system with a system and method for calculation of the net output torque from the waste heat recovery system. The calculation uses inputs from existing pressure and speed sensors to create a virtual pump torque sensor and a virtual expander torque sensor, and uses these sensors to provide an accurate net torque output from the WHR system.
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Wang, Y B; Wu, P T; Engel, B A; Sun, S K
2014-11-01
Water shortages are detrimental to China's grain production while food production consumes a great deal of water causing water crises and ecological impacts. Increasing crop water productivity (CWP) is critical, so China is devoting significant resources to develop water-saving agricultural systems based on crop planning and agricultural water conservation planning. A comprehensive CWP index is necessary for such planning. Existing indices such as water use efficiency (WUE) and irrigation efficiency (IE) have limitations and are not suitable for the comprehensive evaluation of CWP. The water footprint (WF) index, calculated using effective precipitation and local water use, has advantages for CWP evaluation. Due to regional differences in crop patterns making the CWP difficult to compare directly across different regions, a unified virtual crop pattern is needed to calculate the WF. This project calculated and compared the WF of each grain crop and the integrated WFs of grain products with actual and virtual crop patterns in different regions of China for 2010. The results showed that there were significant differences for the WF among different crops in the same area or among different areas for the same crop. Rice had the highest WF at 1.39 m(3)/kg, while corn had the lowest at 0.91 m(3)/kg among the main grain crops. The WF of grain products was 1.25 m(3)/kg in China. Crop patterns had an important impact on WF of grain products because significant differences in WF were found between actual and virtual crop patterns in each region. The CWP level can be determined based on the WF of a virtual crop pattern, thereby helping optimize spatial distribution of crops and develop agricultural water savings to increase CWP. Copyright © 2014 Elsevier B.V. All rights reserved.
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Controls of the U.S. Virtual Water Transfer Network
Garcia, S.; Mejia, A.
2017-12-01
A complex interplay of human and natural factors shape the economic geography of the U.S., operating through socioeconomic forces that drive the consumption, production, and exchange of commodities. The virtual water content of a commodity represents the water embedded in its production. This work investigates the controls of national bilateral transfers of the virtual water transfer network (VWTN), through a gravity-type spatial interaction model. We use a probabilistic model to predict the binary network and investigate whether the gravity model can explain the topological properties of the empirical weighted network. In general, the gravity model relates transfer flows to the mass of the trading regions and their geographical distance. We hypothesize that properties of the nodes such as population, employment, and availability of land, together with the Euclidean distance between two trading regions, capture the main drivers of the national VWTN. The results from the model are then compared to the empirical weighted network to verify its ability to model the structure of this self-organized system. The proposed empirical model provides insight into the processes that underlie the formation of the VWTN. It can be a promising tool to study how flows are affected by changes in the generating conditions due to shocks and/or stresses.
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DeepNet: An Ultrafast Neural Learning Code for Seismic Imaging
International Nuclear Information System (INIS)
Barhen, J.; Protopopescu, V.; Reister, D.
1999-01-01
A feed-forward multilayer neural net is trained to learn the correspondence between seismic data and well logs. The introduction of a virtual input layer, connected to the nominal input layer through a special nonlinear transfer function, enables ultrafast (single iteration), near-optimal training of the net using numerical algebraic techniques. A unique computer code, named DeepNet, has been developed, that has achieved, in actual field demonstrations, results unattainable to date with industry standard tools
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Catch me if you can: Comparing ballast water sampling skids to traditional net sampling
Bradie, Johanna; Gianoli, Claudio; Linley, Robert Dallas; Schillak, Lothar; Schneider, Gerd; Stehouwer, Peter; Bailey, Sarah
2018-03-01
With the recent ratification of the International Convention for the Control and Management of Ships' Ballast Water and Sediments, 2004, it will soon be necessary to assess ships for compliance with ballast water discharge standards. Sampling skids that allow the efficient collection of ballast water samples in a compact space have been developed for this purpose. We ran 22 trials on board the RV Meteor from June 4-15, 2015 to evaluate the performance of three ballast water sampling devices (traditional plankton net, Triton sampling skid, SGS sampling skid) for three organism size classes: ≥ 50 μm, ≥ 10 μm to Natural sea water was run through the ballast water system and untreated samples were collected using paired sampling devices. Collected samples were analyzed in parallel by multiple analysts using several different analytic methods to quantify organism concentrations. To determine whether there were differences in the number of viable organisms collected across sampling devices, results were standardized and statistically treated to filter out other sources of variability, resulting in an outcome variable representing the mean difference in measurements that can be attributed to sampling devices. These results were tested for significance using pairwise Tukey contrasts. Differences in organism concentrations were found in 50% of comparisons between sampling skids and the plankton net for ≥ 50 μm, and ≥ 10 μm to < 50 μm size classes, with net samples containing either higher or lower densities. There were no differences for < 10 μm organisms. Future work will be required to explicitly examine the potential effects of flow velocity, sampling duration, sampled volume, and organism concentrations on sampling device performance.
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Importance of the virtual mass force in accelerating steam/water mixtures
International Nuclear Information System (INIS)
Khalil, Y.F.; Kazimi, M.S.
1987-01-01
Virtual mass force is one of the forces that must be considered against accelerating a dispersed fluid flowing in the bulk of a continuous fluid. This force depends on the geometry of the interface and the flow pattern of the two fluids. For dilute two-phase flow mixtures where the bubbles are singly dispersed, the value of the virtual mass force coefficient is dependent on the geometry of the bubble. However, for high void fraction cases, such as depressurization initiated by a pipe break in light water reactors, more intense interaction is expected between the two phase and, therefore, the value of the virtual mass force must be well defined. The effects of implementing the virtual mass force term in the momentum equations of a two-fluid model may be significant for improving the stability of the solution of the conservation equations, the accuracy of the numerical results, and the computation time. In the current work, a new stability criterion is derived after implementing Hancox's model for the virtual mass force in the momentum equations of the six-equation two-phase flow model of TERMIT. A one-dimensional blow-down in a horizontal pipe is considered to investigate the importance of incorporating the virtual mass force in accelerating mixtures flows
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Tsunamis 406 EPIRB's National Weather Service Marine Forecasts INMARSAT-C SafetyNET Marine Forecast Offices greater danger near shore or any shallow waters? NATIONAL WEATHER SERVICE PRODUCTS VIA INMARSAT-C SafetyNET Inmarsat-C SafetyNET is an internationally adopted, automated satellite system for promulgating
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Characterization of the phantom material Virtual WaterTM in high-energy photon and electron beams
International Nuclear Information System (INIS)
McEwen, M.R.; Niven, D.
2006-01-01
The material Virtual Water TM has been characterized in photon and electron beams. Range-scaling factors and fluence correction factors were obtained, the latter with an uncertainty of around 0.2%. This level of uncertainty means that it may be possible to perform dosimetry in a solid phantom with an accuracy approaching that of measurements in water. Two formulations of Virtual Water TM were investigated with nominally the same elemental composition but differing densities. For photon beams neither formulation showed exact water equivalence--the water/Virtual Water TM dose ratio varied with the depth of measurement with a difference of over 1% at 10 cm depth. However, by using a density (range) scaling factor very good agreement ( TM at all depths was obtained. In the case of electron beams a range-scaling factor was also required to match the shapes of the depth dose curves in water and Virtual Wate TM . However, there remained a difference in the measured fluence in the two phantoms after this scaling factor had been applied. For measurements around the peak of the depth-dose curve and the reference depth this difference showed some small energy dependence but was in the range 0.1%-0.4%. Perturbation measurements have indicated that small slabs of material upstream of a detector have a small (<0.1% effect) on the chamber reading but material behind the detector can have a larger effect. This has consequences for the design of experiments and in the comparison of measurements and Monte Carlo-derived values
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Yang, Shihong; Xiao, Ya Nan; Xu, Junzeng
2018-04-01
Quantifying carbon sequestration in paddy soil is necessary to understand the effect of agricultural practices on carbon cycles. The objective of this study was to assess the effect of organic fertilizer addition (MF) on the soil respiration and net ecosystem carbon dioxide (CO 2 ) absorption of paddy fields under water-saving irrigation (CI) in the Taihu Lake Region of China during the 2014 and 2015 rice-growing seasons. Compared with the traditional fertilizer and water management (FC), the joint regulation of CI and MF (CM) significantly increased the rice yields and irrigation water use efficiencies of paddy fields by 4.02~5.08 and 83.54~109.97% (p < 0.05). The effects of organic fertilizer addition on soil respiration and net ecosystem CO 2 absorption rates showed inter-annual differences. CM paddy fields showed a higher soil respiration and net CO 2 absorption rates during some periods of the rice growth stage in the first year and during most periods of the rice growth stage in the second year. These fields also had significantly higher total CO 2 emission through soil respiration (total R soil ) and total net CO 2 absorption compared with FC paddy fields (p < 0.05). The total R soil and net ecosystem CO 2 absorption of CM paddy fields were 67.39~91.55 and 129.41~113.75 mol m -2 , which were 27.66~135.52 and 12.96~31.66% higher than those of FC paddy fields. The interaction between water and fertilizer management had significant effects on total net ecosystem CO 2 absorption. The frequent alternate wet-dry cycles of CI paddy fields increased the soil respiration and reduced the net CO 2 absorption. Organic fertilizer promoted the soil respiration of paddy soil but also increased its net CO 2 absorption and organic carbon content. Therefore, the joint regulation of water-saving irrigation and organic fertilizer is an effective measure for maintaining yield, increasing irrigation water use efficiency, mitigating CO 2 emission, and promoting paddy
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OtagoNet: One Region's Model for Virtual Schooling
Pratt, Keryn; Pullar, Ken
2013-01-01
Virtual schools are increasingly common in New Zealand and internationally as schools are challenged to meet the needs of their students. This article presents a description of the distance-learning model used by a group of schools in rural Otago for the last decade. The leadership team and roles are described, and the funding model, which is…
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Improving Virtual Collaborative Learning through Canonical Action Research
Weber, Peter; Lehr, Christian; Gersch, Martin
2014-01-01
Virtual collaboration continues to gain in significance and is attracting attention also as virtual collaborative learning (VCL) in education. This paper addresses aspects of VCL that we identified as critical in a series of courses named "Net Economy": (1) technical infrastructure, (2) motivation and collaboration, and (3) assessment…
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Baldisserotto, Bernardo; Copatti, Carlos E; Gomes, Levy C; Chagas, Edsandra C; Brinn, Richard P; Roubach, Rodrigo
2008-12-01
Fishes that live in the Amazon environment may be exposed to several kinds of water: black water (BW), acidic black water (pH 3.5) (ABW) and white water (WW), among others. The aim of the present study was to analyze net ion fluxes in the facultative air-breather Hoplosternum littorale (tamoata) and the obligate air-breather Arapaima gigas (pirarucu) exposed to different types of water. Fishes were acclimated in well water and later placed in individual chambers containing one type of water for ion flux measurements. After 4 h, the water in the chambers was replaced by a different type of water. The transfer of both species to ABW (independent of previous water exposure) increased net ion loss. Tamoatas transferred from ABW to BW or WW presented a net ion influx, but pirarucus showed only small changes on net ion efflux. These results allow us to conclude that tamoatas and pirarucus present differences in terms of ion regulation but that the general aspects of the ion flux are similar: (1) exposure to ABW led to net ion loss; (2) transfer from BW to WW or vice-versa induced only minor changes on net ion fluxes. These observations demonstrate that any osmoregulatory difficulties encountered by either species during changes between these latter two waters can be easily overcome.
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The Comparison of Virtual Water Consumption among the Various Consumption Patterns of Diet
SHANG Hai-yang
2015-01-01
Water resource is the basic and necessary input in the process of production and various consumption patterns of products and goods causes cause different impacts on the water resource using. It is very important to analysis and measures those different influences, which is especially good for the sustainability of water resource, construction of sustainable consumption pattern and the implementation of Integrated Water Resource Management. In this text, the virtual water consumption of Gansu...
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Declarative virtual water maze learning and emotional fear conditioning in primary insomnia.
Kuhn, Marion; Hertenstein, Elisabeth; Feige, Bernd; Landmann, Nina; Spiegelhalder, Kai; Baglioni, Chiara; Hemmerling, Johanna; Durand, Diana; Frase, Lukas; Klöppel, Stefan; Riemann, Dieter; Nissen, Christoph
2018-05-02
Healthy sleep restores the brain's ability to adapt to novel input through memory formation based on activity-dependent refinements of the strength of neural transmission across synapses (synaptic plasticity). In line with this framework, patients with primary insomnia often report subjective memory impairment. However, investigations of memory performance did not produce conclusive results. The aim of this study was to further investigate memory performance in patients with primary insomnia in comparison to healthy controls, using two well-characterized learning tasks, a declarative virtual water maze task and emotional fear conditioning. Twenty patients with primary insomnia according to DSM-IV criteria (17 females, three males, 43.5 ± 13.0 years) and 20 good sleeper controls (17 females, three males, 41.7 ± 12.8 years) were investigated in a parallel-group study. All participants completed a hippocampus-dependent virtual Morris water maze task and amygdala-dependent classical fear conditioning. Patients with insomnia showed significantly delayed memory acquisition in the virtual water maze task, but no significant difference in fear acquisition compared with controls. These findings are consistent with the notion that memory processes that emerge from synaptic refinements in a hippocampal-neocortical network are particularly sensitive to chronic disruptions of sleep, while those in a basic emotional amygdala-dependent network may be more resilient. © 2018 European Sleep Research Society.
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Klipstein, A.; Schneider, K.; Breuer, L.; Frede, H. G.
2009-04-01
Due to low annual precipitation, agricultural production in Uzbekistan is depending on irrigation from the Syrdarya and Amudarya rivers to a great deal. One of the most important cash crops of the country is cotton. Current irrigation management leads to elevated groundwater levels, salinization of soils and to a degradation of soil and water resources. Through export of cotton and other crops, the problems related to water consumption and water management are transported beyond the producing country. The amount of water transported through production and export is referred to as virtual water. To distinguish between productive and unproductive partitioning of water flows, the terms green and blue water have been introduced. Information on virtual water flows due to crop production usually only exist on country level. To reduce uncertainties related to generalization, the effect of land management and environmental factors on the partitioning of water flows needs to be studied on smaller scales. The presented study analyzes water fluxes in an intensively used agricultural area in the Fergana Valley, Uzbekistan. The study aims to a) quantify crop specific water consumption in agricultural production under current management and b) analyze water use efficiency as subject to land use and irrigation management. Based on crop production, irrigation management and environmental conditions in the study area, virtual water flows will be calculated on the level of agricultural collectives (Water Users Associations). In a further step, the partitioning of green and blue water fluxes will be quantified. Alternative scenarios for improved water management will be analyzed in a model study.
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Well-to-Wheels Water Consumption: Tracking the Virtual Flow of Water into Transportation
Lampert, D. J.; Elgowainy, A.; Hao, C.
2015-12-01
Water and energy resources are fundamental to life on Earth and essential for the production of consumer goods and services in the economy. Energy and water resources are heavily interdependent—energy production consumes water, while water treatment and distribution consume energy. One example of this so-called energy-water nexus is the consumption of water associated with the production of transportation fuels. The Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model is an analytical tool that can be used to compare the environmental impacts of different transportation fuels on a consistent basis. In this presentation, the expansion of GREET to perform life cycle water accounting or the "virtual flow" of water into transportation and other energy sectors and the associated implications will be discussed. The results indicate that increased usage of alternative fuels may increase freshwater resource consumption. The increased water consumption must be weighed against the benefits of decreased greenhouse gas and fossil energy consumption. Our analysis highlights the importance of regionality, co-product allocation, and consistent system boundaries when comparing the water intensity of alternative transportation fuel production pathways such as ethanol, biodiesel, compressed natural gas, hydrogen, and electricity with conventional petroleum-based fuels such as diesel and gasoline.
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Virtual reality application for simulating and minimizing worker radiation exposure
International Nuclear Information System (INIS)
Kang, Ki Doo; Hajek, Brian K.; Lee, Yon Sik; Shin, Yoo Jin
2004-01-01
To plan work and preclude unexpected radiation exposures in a nuclear power plant, a virtual nuclear plant is a good solution. For this, there are prerequisites such as displaying real time radiation exposure data onto an avatar and preventing speed reduction caused by multiple users on the net-based system. The work space is divided into several sections and radiation information is extracted section by section. Based on the simulation algorithm, real time processing is applied to the events and movements of the avatar. Because there are millions of parts in a nuclear power plant, it is almost impossible to model all of them. Several parts of virtual plant have been modeled using 3D internet virtual reality for the model development. Optimum one-click Active-X is applied for the system, which provides easy access to the virtual plant. Connection time on the net is 20-30 sec for initial loading and 3-4 sec for the 2nd and subsequent times
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A Tutoring Wizard Guiding Tutorial Work in the Virtual University.
Mittrach, Silke; Schlageter, Gunter
The Virtual University is an Internet-based learning environment developed at the University of Hagen (Germany). Complex teaching activities based on new concepts integrating net-based communication and cooperation facilities take place in the Virtual University. Experiences show that there is a threshold, especially for tutors in non-computer…
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International Virtual Observatory System for Water Resources Information
Leinenweber, Lewis; Bermudez, Luis
2013-04-01
Sharing, accessing, and integrating hydrologic and climatic data have been identified as a critical need for some time. The current state of data portals, standards, technologies, activities, and expertise can be leverage to develop an initial operational capability for a virtual observatory system. This system will allow to link observations data with stream networks and models, and to solve semantic inconsistencies among communities. Prototyping a virtual observatory system is an inter-disciplinary, inter-agency and international endeavor. The Open Geospatial Consortium (OGC) within the OGC Interoperability Program provides the process and expertise to run such collaborative effort. The OGC serves as a global forum for the collaboration of developers and users of spatial data products and services, and to advance the development of international standards for geospatial interoperability. The project coordinated by OGC that is advancing an international virtual observatory system for water resources information is called Climatology-Hydrology Information Sharing Pilot, Phase 1 (CHISP-1). It includes observations and forecasts in the U.S. and Canada levering current networks and capabilities. It is designed to support the following use cases: 1) Hydrologic modeling for historical and near-future stream flow and groundwater conditions. Requires the integration of trans-boundary stream flow and groundwater well data, as well as national river networks (US NHD and Canada NHN) from multiple agencies. Emphasis will be on time series data and real-time flood monitoring. 2) Modeling and assessment of nutrient load into the lakes. Requires accessing water-quality data from multiple agencies and integrating with stream flow information for calculating loads. Emphasis on discrete sampled water quality observations, linking those to specific NHD stream reaches and catchments, and additional metadata for sampled data. The key objectives of these use cases are: 1) To link
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Water consumption in artificial desert oasis based on net primary productivity
Institute of Scientific and Technical Information of China (English)
无
2010-01-01
Analysis of the water consumption is the basis for water allocation in oasis. However, the method of estimating oasis water consumption remains a great challenge. Based on net primary productivity (NPP) and the transpiration coefficient, a vegetation water consumption model was developed to estimate the water consumption in desert oasis in ERDAS environment. Our results demonstrated that the ecosystem in the middle reaches of the Heihe oasis consumed water of 18.41×108-21.9×108 m3 for irrigation. Without taking precipitation into account, the water consumption in farmland accounted for 77.1%-77.8% (or about 13.97×108-16.84×108 m3) of the oasis vegetation water consumption and in the farmland protection system accounting for 22%. The growing period precipitation in desert environments is about 7.02×108 m3, and the total annual precipitation is about 8.29×108 m3. The modeled water consumption of desert vegetation, however, is about 4.57×108 m3, equivalent to only 65% of the growing period precipitation or 55% of the total annual precipitation. The modeled value equals to the cumulative precipitation of greater than 5 mm, which is defined as the effective precipitation in arid desert.
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LeatherNet: an evaluation as a mission planning and briefing tool
Hague, Tracy R.
1996-01-01
Information Technology Management The author evaluates LeatherNet, a Distributed Interactive Simulation compliant, virtual simulation system being developed by the Advanced Research Projects Agency to demonstrate Modeling and Simulation(M&S) technologies and to partially fulfill the U. S. Marine Corps M&S goals. The research focuses on evaluation of LeatherNet as a mission planning and briefing tool for Marine infantry company commanders, staff, and subordinate leaders. Evaluation is based...
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Directory of Open Access Journals (Sweden)
Michael A. Persinger
2015-09-01
Full Text Available The ~1.5 × 10−20 J which is considered a universal quantity and is associated with the movement of protons in water also relates to the ratio of the magnetic moment of a proton divided by its unit charge, multiplied by viscosity and applied over the O-H distance. There is quantitative evidence that thixotropy, the “spontaneous” increased viscosity in water when undisturbed, originates from the transformation of virtual particles or vacuum oscillations to real states through conversion of Casimir-magnetic energies that involve the frequency of the neutral hydrogen line and the upper bound threshold value for intergalactic magnetic fields. The results indicate that ½ of a single electron orbit is real (particle and the other ½ is virtual (wave. The matter equivalent per s for virtual-to-real states for electrons in 1 mL of water with a neutral pH is consistent with the numbers of protons (H+ and the measured range of molecules in the coherent domains for both width and duration of growth and is similar to widths of intergalactic dust grains from which planets and stars may condense. The de Broglie momentum for the lower boundary of the width of coherent domains multiplied by the fine structure velocity of an electron is concurrent with the quantum when one proton is being removed from another and when the upper boundary of the rest mass of a photon is transformed by the product of velocities for putative “entanglement” and light. Theoretical and experimental results indicate that components of thixotropy, such as specific domains of intercalated water molecules, could display excess correlations over very large distances. Because the energies of the universal quantity and water converge it may be a special conduit for discrete transformations from virtual to real states.
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The influence of fish culture in floating net cages on microbial indicators of water quality
Directory of Open Access Journals (Sweden)
K. Gorlach-Lira
Full Text Available This work was carried out to analyse the microbiological parameters of the water quality of a reservoir used for the irrigation and culture of tilapia (Oreochromis niloticus in floating net cages. The physico-chemical parameters, counts of mesophilic total aerobic bacteria, total and thermotolerant coliforms and fecal streptococci, and the presence of Escherichia coli in samples of water collected in three sites of the reservoir (pre-culture site, culture site, post-culture site were analysed. The levels of ammonia (0.047-0.059 mg/L, nitrite (0.001-0.021 mg/L and total phosphorus (0.050-0.355 mg/L in the water did not show significant differences (p > 0.05 between sampling sites. The levels of total bacteria in the water varied between 1.3 x 104 and 67.3 x 104 CFU/100 mL. The MPN values of thermotolerant coliforms (< 930 MPN/100 mL were within values recommended for water used for fish culture and/or irrigation. The presence of E. coli and fecal streptococci were verified in 48% and 56% of analysed samples, respectively. The site with floating net cages showed more samples contaminated with E. coli and fecal streptococci than other sampling points.
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Military bases resemble small cities and face similar sustainability challenges. As pilot studies in the U.S. Army Net Zero program, 17 locations are moving to 100% renewable energy, zero depletion of water resources, and/or zero waste to landfill by 2020. Some bases target net z...
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Foodsheds in Virtual Water Flow Networks: A Spectral Graph Theory Approach
Directory of Open Access Journals (Sweden)
Nina Kshetry
2017-06-01
Full Text Available A foodshed is a geographic area from which a population derives its food supply, but a method to determine boundaries of foodsheds has not been formalized. Drawing on the food–water–energy nexus, we propose a formal network science definition of foodsheds by using data from virtual water flows, i.e., water that is virtually embedded in food. In particular, we use spectral graph partitioning for directed graphs. If foodsheds turn out to be geographically compact, it suggests the food system is local and therefore reduces energy and externality costs of food transport. Using our proposed method we compute foodshed boundaries at the global-scale, and at the national-scale in the case of two of the largest agricultural countries: India and the United States. Based on our determination of foodshed boundaries, we are able to better understand commodity flows and whether foodsheds are contiguous and compact, and other factors that impact environmental sustainability. The formal method we propose may be used more broadly to study commodity flows and their impact on environmental sustainability.
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Mineralizing urban net-zero water treatment: Field experience for energy-positive water management.
Wu, Tingting; Englehardt, James D
2016-12-01
An urban net-zero water treatment system, designed for energy-positive water management, 100% recycle of comingled black/grey water to drinking water standards, and mineralization of hormones and other organics, without production of concentrate, was constructed and operated for two years, serving an occupied four-bedroom, four-bath university residence hall apartment. The system comprised septic tank, denitrifying membrane bioreactor (MBR), iron-mediated aeration (IMA) reactor, vacuum ultrafilter, and peroxone or UV/H 2 O 2 advanced oxidation, with 14% rainwater make-up and concomitant discharge of 14% of treated water (ultimately for reuse in irrigation). Chemical oxygen demand was reduced to 12.9 ± 3.7 mg/L by MBR and further decreased to below the detection limit (treatment. The process produced a mineral water meeting 115 of 115 Florida drinking water standards that, after 10 months of recycle operation with ∼14% rainwater make-up, had a total dissolved solids of ∼500 mg/L, pH 7.8 ± 0.4, turbidity 0.12 ± 0.06 NTU, and NO 3 -N concentration 3.0 ± 1.0 mg/L. None of 97 hormones, personal care products, and pharmaceuticals analyzed were detected in the product water. For a typical single-home system with full occupancy, sludge pumping is projected on a 12-24 month cycle. Operational aspects, including disinfection requirements, pH evolution through the process, mineral control, advanced oxidation by-products, and applicability of point-of-use filters, are discussed. A distributed, peroxone-based NZW management system is projected to save more energy than is consumed in treatment, due largely to retention of wastewater thermal energy. Recommendations regarding design and operation are offered. Copyright © 2016 Elsevier Ltd. All rights reserved.
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CM Net heterogeneous local network of microcomputers
International Nuclear Information System (INIS)
Gutche, R.Kh.
1988-01-01
Realization of the CM Net heterogeneous local network for the PDP-11 type computers with the RT-11 operational system control is described. The main advantage of the network is the realization of virtual disks in general form including a system unit. the network can be used everywhere, where the problem on computer connection by simple interfaces is stated. 6 refs
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Evaluation of water balance parameters from isotopic measurements in evaporation pans
International Nuclear Information System (INIS)
Allison, G.B.
1979-01-01
The evaluation of the parameters governing the isotopic composition of evaporating water bodies was attempted by means of evaporation pans. The instability of the meteorological conditions, however, makes it virtually impossible to evaluate the atmospheric relative humidity and its isotopic composition with pans. Pans are only suitable to obtain seasonal trends of the isotopic composition of the net evaporated water. For this, a technique based on two pans is also proposed. (author)
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Madel, R.; Olson-Sawyer, K.; Hanlon, P.; Rabin, K.
2017-12-01
Attari (2014) has shown through online surveys that Americans underestimate their water use, don't know what their water footprint is and don't know how much water it takes to produce food. The more people know about their water use, the better decisions they are capable of making and the more likely they are to conserve, which is especially important during periods of water stress. To increase awareness and help people decrease their daily water use, GRACE Communications Foundation created a Water Footprint Calculator [watercalculator.org] using US-oriented data and presented in US units in both English and Spanish. The calculator is based on direct water use data as well as the water consumed to create food, consumer goods and energy (also known as virtual or indirect water use). We learned that there is a lack of comparably-scaled, consumer-level virtual water research available. The direct use data gathered for the calculator came primarily from a study of residential water use in the US by Mayer et al. (1999), who conducted surveys of households in different US cities and averaged data for both inside and outside the home. The indirect use data came from various sources including the US government (USGS, EPA, EIA, NREL, Energy Star, etc.), the Water Footprint Network and the UN FAO. Much of the indirect use data was aggregated at a national level or came from combinations of various data sets. For all users, the food category accounts for the largest part of their water footprints. Gathering data of comparable scale at a personal consumption level proved to be a challenging exercise and provided several takeaways. While there is recent residential direct water use data at a consumer level, there is a lack of data at the personal, consumer level about indirect water use in manufacturing, energy production and agriculture. Because of this, we had to use national averages and generalized calculations. The resulting tool gives people a sense of the impacts of
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DEFF Research Database (Denmark)
Walli, A.; Tøttrup, C.; Naeimi, V.
As part of the TIGER initiative [1] the TIGER-NET project aims to support the assessment and monitoring of water resources from watershed to transboundary basin level delivering indispensable information for Integrated Water Resource Management in Africa through: 1. Development of an open......-source Water Observation and Information Systems (WOIS) for monitoring, assessing and inventorying water resources in a cost-effective manner; 2. Capacity building and training of African water authorities and technical centers to fully exploit the increasing observation capacity offered by current...... and upcoming generations of satellites, including the Sentinel missions. Dedicated application case studies have been developed and demonstrated covering all EO products required by and developed with the participating African water authorities for their water resource management tasks, such as water reservoir...
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Heavy Analysis and Light Virtualization of Water Use Data with Python
Kim, H.; Bijoor, N.; Famiglietti, J. S.
2014-12-01
Water utilities possess a large amount of water data that could be used to inform urban ecohydrology, management decisions, and conservation policies, but such data are rarely analyzed owing to difficulty in analyzation, visualization, and interpretion. We have developed a high performance computing resource for this purpose. We partnered with 6 water agencies in Orange County who provided 10 years of parcel-level monthly water use billing data for a pilot study. The first challenge that we overcame was to refine all human errors and unify the many different formats of data over all agencies. Second, we tested and applied experimental approaches to the data, including complex calculations, with high efficiency. Third, we developed a method to refine the data so it can be browsed along a time series index and/or geo-spatial queries with high efficiency, no matter how large the data. Python scientific libraries were the best match to handle arbitrary data sets in our environment. Further milestones include agency entry, sets of formulae, and maintaining 15M rows X 70 columns of data with high performance of cpu-bound processes. To deal with billions of rows, we performed an analysis virtualization stack by leveraging iPython parallel computing. With this architecture, one agency could be considered one computing node or virtual machine that maintains its own data sets respectively. For example, a big agency could use a large node, and a small agency could use a micro node. Under the minimum required raw data specs, more agencies could be analyzed. The program developed in this study simplifies data analysis, visualization, and interpretation of large water datasets, and can be used to analyze large data volumes from water agencies nationally or worldwide.
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Shtull-Trauring, E; Bernstein, N
2018-05-01
Agriculture is the largest global consumer of freshwater. As the volume of international trade continues to rise, so does the understanding that trade of water-intensive crops from areas with high precipitation, to arid regions can help mitigate water scarcity, highlighting the importance of crop water accounting. Virtual-Water, or Water-Footprint [WF] of agricultural crops, is a powerful indicator for assessing the extent of water use by plants, contamination of water bodies by agricultural practices and trade between countries, which underlies any international trade of crops. Most available studies of virtual-water flows by import/export of agricultural commodities were based on global databases, which are considered to be of limited accuracy. The present study analyzes the WF of crop production, import, and export on a country level, using Israel as a case study, comparing data from two high-resolution local databases and two global datasets. Results for local datasets demonstrate a WF of ~1200Million Cubic Meters [MCM]/year) for total crop production, ~1000MCM/year for import and ~250MCM/year for export. Fruits and vegetables comprise ~80% of Export WF (~200MCM/year), ~50% of crop production and only ~20% of the imports. Economic Water Productivity [EWP] ($/m 3 ) for fruits and vegetables is 1.5 higher compared to other crops. Moreover, the results based on local and global datasets varied significantly, demonstrating the importance of developing high-resolution local datasets based on local crop coefficients. Performing high resolution WF analysis can help in developing agricultural policies that include support for low WF/high EWP and limit high WF/low EWP crop export, where water availability is limited. Copyright © 2017 Elsevier B.V. All rights reserved.
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Ma, Xiaolei; Ma, Yanji
2017-05-15
With the rapid development of economic, water crisis is becoming more and more serious and would be an important obstacle to the sustainable development of society. Virtual water theory and its applications in agriculture can provide important strategies for realizing the reasonable utilization and sustainable development of water resources. Using the Penman-Monteith model and Theil index combining the CROPWAT software, this work takes Jilin Province as study area quantifying the virtual water content of agriculture and livestock husbandry and giving a comprehensive evaluation of their spatiotemporal structure evolution. This study aims to help make clear the water consumption of agriculture and livestock husbandry, and offer advice on rational water utilization and agricultural structure adjustment. The results show that the total virtual water (TVW) proportion of agriculture presents a gradual growth trend while that of livestock husbandry reduces during the study period. In space, central Jilin shows the highest virtual water content of agriculture as well as livestock husbandry, the TVW in central Jilin is about 35.8billionm 3 . The TVW of maize is highest among six studied crops, and the cattle shows the highest TVW in the four kinds of animals. The distribution of TVW calculated by us and the distribution of actual water resources have remarkable difference, which leads to the increase of water consumption and cost of agricultural production. Finally, we discuss the driving force of the spatiotemporal variation of the TVW for agriculture and livestock husbandry, and also give some advises for the planting structural adjustment. This work is helpful for the sustainable development of agricultural and livestock husbandry and realizing efficient utilization of water resources. Copyright © 2017 Elsevier B.V. All rights reserved.
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Hasik, Vaclav; Anderson, Naomi E; Collinge, William O; Thiel, Cassandra L; Khanna, Vikas; Wirick, Jason; Piacentini, Richard; Landis, Amy E; Bilec, Melissa M
2017-02-07
Aging water infrastructure and increased water scarcity have resulted in higher interest in water reuse and decentralization. Rating systems for high-performance buildings implicitly promote the use of building-scale, decentralized water supply and treatment technologies. It is important to recognize the potential benefits and trade-offs of decentralized and centralized water systems in the context of high-performance buildings. For this reason and to fill a gap in the current literature, we completed a life cycle assessment (LCA) of the decentralized water system of a high-performance, net-zero energy, net-zero water building (NZB) that received multiple green building certifications and compared the results with two modeled buildings (conventional and water efficient) using centralized water systems. We investigated the NZB's impacts over varying lifetimes, conducted a break-even analysis, and included Monte Carlo uncertainty analysis. The results show that, although the NZB performs better in most categories than the conventional building, the water efficient building generally outperforms the NZB. The lifetime of the NZB, septic tank aeration, and use of solar energy have been found to be important factors in the NZB's impacts. While these findings are specific to the case study building, location, and treatment technologies, the framework for comparison of water and wastewater impacts of various buildings can be applied during building design to aid decision making. As we design and operate high-performance buildings, the potential trade-offs of advanced decentralized water treatment systems should be considered.
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Wang, Ranran; Zimmerman, Julie
2016-05-17
As the fifth global water footprint assessment, this study enhanced previous estimates of national blue water consumption (including fresh surface and groundwater) and main economic activities with (1) improved spatial and sectoral resolution and (2) quantified the impacts of virtual water trade on water use and water stress at both the national and basin level. In 2007, 1194 Gm(3) of blue water was consumed globally for human purposes. The consuming (producing) of primary and manufactured goods and services from the sectors of "Primary Crops and Livestock", "Primary Energy and Minerals", "Processed Food and Beverages", "Non-food Manufactured Products", "Electricity", "Commercial and Public Services", and "Households" accounted for 33% (91%), ∼ 0% (1%), 37% (water consumption, respectively. The considerable differences in sectoral water consumption accounted for by the two perspectives (consumption- vs production-based) highlight the significance of the water consumed indirectly, upstream in the supply chain (i.e., > 70% of total blue water consumption) while offering additional insights into the water implications of critical interconnected economic activities, such as the water-energy nexus. With 145 Gm(3) (12%) of the blue water consumption embedded in the goods and services traded internationally, 89 countries analyzed were net blue water importers at the national level. On the basin level, the impacts of virtual water trade on water stress were statistically significant for basins across the world and within 104 countries; virtual water trade mitigated water stress for the basins within 85 of the 104 countries, including all of those where there are moderate and greater water stress countrywide (except Italy).
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Annual and Seasonal Mean Net Evaporation Rates of the Red Sea Water during Jan 1958 - Dec 2007
Nassir, Sahbaldeen Abdulaziz
2012-01-01
Data set including sea level, temperature, salinity, and current from Simple Ocean Data Assimilation (SODA) is used in this study to estimate the mean net annually and seasonally evaporation rates. Then wind data is used to examine its impact on the evaporation. This work calculated the seasonal and annual evaporation rates based on assumption of that there is no net mass transport (balanced). Hence, the difference in the transport supposed to be equal to the water that has eva...
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International Nuclear Information System (INIS)
Chazalon, M.; Daenner, W.; Libin, B.
1989-01-01
The testing stages in NET for the performance assessment of the various breeding blanket concepts developed at the present time in Europe for DEMO (LiPb and ceramic blankets) and the requirements upon NET to perform these tests are reviewed. Typical locations available in NET for blanket testing are the central outboard segments and the horizontal ports of in-vessel sectors. These test positions will be connectable with external test loops. The number of test loops (helium, water, liquid metal) will be such that each major class of blankets can be tested in NET. The test positions, the boundary conditions and the external test loops are identified and the requirements for test blankets are summarized (author). 6
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Increasing air temperature is expected to extend growing season length in temperate, broadleaf forests, leading to potential increases in evapotranspiration and net carbon uptake. However, other key processes affecting water and carbon cycles are also highly temperature-dependent...
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Zhuo, La; Mekonnen, Mesfin M; Hoekstra, Arjen Y
2016-05-01
Previous studies into the relation between human consumption and indirect water resources use have unveiled the remote connections in virtual water (VW) trade networks, which show how communities externalize their water footprint (WF) to places far beyond their own region, but little has been done to understand variability in time. This study quantifies the effect of inter-annual variability of consumption, production, trade and climate on WF and VW trade, using China over the period 1978-2008 as a case study. Evapotranspiration, crop yields and green and blue WFs of crops are estimated at a 5 × 5 arc-minute resolution for 22 crops, for each year in the study period, thus accounting for climate variability. The results show that crop yield improvements during the study period helped to reduce the national average WF of crop consumption per capita by 23%, with a decreasing contribution to the total from cereals and increasing contribution from oil crops. The total consumptive WFs of national crop consumption and crop production, however, grew by 6% and 7%, respectively. By 2008, 28% of total water consumption in crop fields in China served the production of crops for export to other regions and, on average, 35% of the crop-related WF of a Chinese consumer was outside its own province. Historically, the net VW within China was from the water-rich South to the water-scarce North, but intensifying North-to-South crop trade reversed the net VW flow since 2000, which amounted 6% of North's WF of crop production in 2008. South China thus gradually became dependent on food supply from the water-scarce North. Besides, during the whole study period, China's domestic inter-regional VW flows went dominantly from areas with a relatively large to areas with a relatively small blue WF per unit of crop, which in 2008 resulted in a trade-related blue water loss of 7% of the national total blue WF of crop production. The case of China shows that domestic trade, as governed by
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Directory of Open Access Journals (Sweden)
Andhika Prima Prasetyo
2014-12-01
Full Text Available This paper aims to develop cost-effective approach regarding the estimation unreported annual catch data of lift-net fishery using Google Earth imagery. Lift net fishery is one of the main fishing activities of coastal community in Kwandang Bay, it has been faced problem of uncertain fisheries status due to limited recorded data. Combination of a Monte Carlo procedure was applied by involving couple of assumptions on parameters such as estimate growth rate of the total number of lift-net per years (10%, day at sea per unit per month (21 days and operated lift-net per month (50% and 80%. The results showed that 101 units of lift-nets were found around Kwandang waters based on Google Earth imagery recorded in October, 7th 2010, and this were used as a benchmark of calculation. This prediction was 28 units higher than official data from North Gorontalo District of Marine Affairs and Fisheries Services (DKP Gorontalo Utara. Compared with capture fisheries statistics issued by Kwandang CFP, the estimated lift-net catches based on two-scenarios represent additional catches of 46 % and 86 %. These results suggested and could be used as a correction index to improve the reliability of Kwandang District officially reported fisheries statistics as a baseline to develop a local common fisheries policy.
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The phase diagram of water at negative pressures: virtual ices.
Conde, M M; Vega, C; Tribello, G A; Slater, B
2009-07-21
The phase diagram of water at negative pressures as obtained from computer simulations for two models of water, TIP4P/2005 and TIP5P is presented. Several solid structures with lower densities than ice Ih, so-called virtual ices, were considered as possible candidates to occupy the negative pressure region of the phase diagram of water. In particular the empty hydrate structures sI, sII, and sH and another, recently proposed, low-density ice structure. The relative stabilities of these structures at 0 K was determined using empirical water potentials and density functional theory calculations. By performing free energy calculations and Gibbs-Duhem integration the phase diagram of TIP4P/2005 was determined at negative pressures. The empty hydrates sII and sH appear to be the stable solid phases of water at negative pressures. The phase boundary between ice Ih and sII clathrate occurs at moderate negative pressures, while at large negative pressures sH becomes the most stable phase. This behavior is in reasonable agreement with what is observed in density functional theory calculations.
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From We-Media to I-Media: Identity Transformations in the Virtual World
Directory of Open Access Journals (Sweden)
Alexandr G. Asmolov
2009-01-01
Full Text Available The blogs as the platform for a virtual personality construction are considered in the article on the assumption of the positions of Lev S.Vygotsky’s cultural-historical approach. Internet journalism practices are considered as the example for the processes of virtual “I” formation. The authors affirm that the appearance of consecutive and stable “I-representation” in Internet is the necessary condition for a change in dynamics of social nets development from motives which are out of Internet in physical space towards situation when a virtual personality is enough full-fledged to be a motive for new social interactions creation not leaving Internet. As a result a virtual personality turns into a net-creating factor and Internet loses its unoriginality in relation to physical space. Using Lev Vygotsky’s “internal speech” concept, the article suggests to consider this interaction as a dairy discourse – “A dialog of internal voices”, which turns a virtual personality from the product of self representation into the product of social interaction. The authors affirm that the ability to construct a virtual personality is the integral part for personality formation in the new information society and propose to regard journalism practices as one of the methods of effective self representation in Internet.
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MLS-Net and SecureParser®: A New Method for Securing and Segregating Network Data
Directory of Open Access Journals (Sweden)
Robert A. Johnson
2008-10-01
Full Text Available A new method of network security and virtualization is presented which allows the consolidation of multiple network infrastructures dedicated to single security levels or communities of interest onto a single, virtualized network. An overview of the state of the art of network security protocols is presented, including the use of SSL, IPSec, and HAIPE IS, followed by a discussion of the SecureParser® technology and MLS-Net architecture, which in combination allow the virtualization of local network enclaves.
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Microbial activity in district cooling nets; Mikrobiell Aktivitet i Fjaerrkylenaet
Energy Technology Data Exchange (ETDEWEB)
Nordling, Magnus [Swedish Corrosion Inst., Stockholm (Sweden)
2004-07-01
Four district cooling nets with varying water quality have been investigated according to presence of microbially related problems. The aim has been to formulate recommendations regarding the water quality and regarding other procedures that might reduce the risk for biofilm formation and microbial corrosion. The method has consisted of using so called exposure containers, connected to each net. The water has been allowed to flow through the exposure containers where coupons of carbon steel have been exposed. The coupons have been withdrawn at different times, and analysed regarding the presence of biofilm and corrosion attack. Analyses have also been made regarding the amount of a number of different types of micro-organisms in the biofilm and in the district cooling water. The project has been divided in two phases. During the first phase of the project only two nets were investigated, one with municipal water and one with water of district heating quality, i.e. degassed and deionised. Biofilms could be seen on the coupons from both nets, even though the exposure time only had been 1.5 month. Considerable concentrations of micro-organisms were found in the biofilms and in the water for both nets, however much larger amounts for the net with municipal water. During the second phase of the project four nets were investigated, two with mainly municipal water and two with water of district heating quality. Here, on the other hand, it could be seen that the two nets with municipal water had micro-organisms of equivalent or lower concentrations compared to the two nets with water of district heating quality. One explanation to this is that the colouring substance pyranine is added to these two nets. Pyranine is added for the purpose of easily detecting a leakage but is at the same time a carbon compound, and as such a possible nutrient for the micro-organisms. This illustrates the importance of having the district cooling water as free from additives as possible. Other
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CSIR Research Space (South Africa)
Dabrowski, James M
2009-10-01
Full Text Available The concept of virtual water encourages a country to view agricultural crops in terms of the amount of water required to produce those crops, with a view to implementing trading policies that promote the saving of scarce water resources. Recently...
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Directory of Open Access Journals (Sweden)
Efraín Alfonso Rubio
1999-07-01
Full Text Available Two species of estuary catfish the Arius kessleri (CoCoCo and the Sciadeops troschelii (Nato were held in floating net cages at varying densities in estuarine waters of Buenventura Bay-Colombia. After 120 days for the Cococo had weights of 84.1 g Y64 g with densities of 5 and 30 specimen/rn'. The growth average was 0.58-0.39 g/day; the net yield obtained vary from 0.35 to 1.16 Kg/m', the food conversion ratio vary from 3.3 to 5.0 and de survival rate vary from 86% to 100%. With the Nato we obtained weights of 164 and 184 g, beginning with weights of 41 and 108 g their growth average vary from 0.50 to 0.82 g/day. The net yield obtained vary from 0.58 to 0.75 Kg/m' and the survival rate vary from 83% to 100%. From these results we conclude that the two species of catfish studied are strong species but they do not offer good possibilities for fish farming in estuarine waters.
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A global sensitivity analysis of crop virtual water content
Tamea, S.; Tuninetti, M.; D'Odorico, P.; Laio, F.; Ridolfi, L.
2015-12-01
The concepts of virtual water and water footprint are becoming widely used in the scientific literature and they are proving their usefulness in a number of multidisciplinary contexts. With such growing interest a measure of data reliability (and uncertainty) is becoming pressing but, as of today, assessments of data sensitivity to model parameters, performed at the global scale, are not known. This contribution aims at filling this gap. Starting point of this study is the evaluation of the green and blue virtual water content (VWC) of four staple crops (i.e. wheat, rice, maize, and soybean) at a global high resolution scale. In each grid cell, the crop VWC is given by the ratio between the total crop evapotranspiration over the growing season and the crop actual yield, where evapotranspiration is determined with a detailed daily soil water balance and actual yield is estimated using country-based data, adjusted to account for spatial variability. The model provides estimates of the VWC at a 5x5 arc minutes and it improves on previous works by using the newest available data and including multi-cropping practices in the evaluation. The model is then used as the basis for a sensitivity analysis, in order to evaluate the role of model parameters in affecting the VWC and to understand how uncertainties in input data propagate and impact the VWC accounting. In each cell, small changes are exerted to one parameter at a time, and a sensitivity index is determined as the ratio between the relative change of VWC and the relative change of the input parameter with respect to its reference value. At the global scale, VWC is found to be most sensitive to the planting date, with a positive (direct) or negative (inverse) sensitivity index depending on the typical season of crop planting date. VWC is also markedly dependent on the length of the growing period, with an increase in length always producing an increase of VWC, but with higher spatial variability for rice than for
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Smith, David W.; Moreo, Michael T.; Garcia, C. Amanda; Halford, Keith J.; Fenelon, Joseph M.
2017-08-29
This report documents a process used to estimate net infiltration from precipitation, evapotranspiration (ET), and soil data acquired at two sites on Rainier Mesa. Rainier Mesa is a groundwater recharge area within the Nevada National Security Site where recharged water flows through bedrock fractures to a deep (450 meters) water table. The U.S. Geological Survey operated two ET stations on Rainier Mesa from 2002 to 2005 at sites characterized by pinyon-juniper and scrub-brush vegetative cover. Precipitation and ET data were corrected to remove measurement biases and gap-filled to develop continuous datasets. Net infiltration (percolation below the root zone) and changes in root-zone water storage were estimated using a monthly water-balance model.Site-scale water-budget results indicate that the heavily-fractured welded-tuff bedrock underlying thin (water source for vegetation during dry periods. Annual precipitation during the study period ranged from fourth lowest (182 millimeters [mm]) to second highest (708 mm) on record (record = 55 years). Annual ET exceeded precipitation during dry years, indicating that the fractured-bedrock reservoir capacity is sufficient to meet atmospheric-evaporative demands and to sustain vegetation through extended dry periods. Net infiltration (82 mm) was simulated during the wet year after the reservoir was rapidly filled to capacity. These results support previous conclusions that preferential fracture flow was induced, resulting in an episodic recharge pulse that was detected in nearby monitoring wells. The occurrence of net infiltration only during the wet year is consistent with detections of water-level rises in nearby monitoring wells that occur only following wet years.
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Urban net-zero water treatment and mineralization: experiments, modeling and design.
Englehardt, James D; Wu, Tingting; Tchobanoglous, George
2013-09-01
Water and wastewater treatment and conveyance account for approximately 4% of US electric consumption, with 80% used for conveyance. Net zero water (NZW) buildings would alleviate demands for a portion of this energy, for water, and for the treatment of drinking water for pesticides and toxic chemical releases in source water. However, domestic wastewater contains nitrogen loads much greater than urban/suburban ecosystems can typically absorb. The purpose of this work was to identify a first design of a denitrifying urban NZW treatment process, operating at ambient temperature and pressure and circum-neutral pH, and providing mineralization of pharmaceuticals (not easily regulated in terms of environmental half-life), based on laboratory tests and mass balance and kinetic modeling. The proposed treatment process is comprised of membrane bioreactor, iron-mediated aeration (IMA, reported previously), vacuum ultrafiltration, and peroxone advanced oxidation, with minor rainwater make-up and H2O2 disinfection residual. Similar to biological systems, minerals accumulate subject to precipitative removal by IMA, salt-free treatment, and minor dilution. Based on laboratory and modeling results, the system can produce potable water with moderate mineral content from commingled domestic wastewater and 10-20% rainwater make-up, under ambient conditions at individual buildings, while denitrifying and reducing chemical oxygen demand to below detection (<3 mg/L). While economics appear competitive, further development and study of steady-state concentrations and sludge management options are needed. Copyright © 2013 Elsevier Ltd. All rights reserved.
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RadNet Air Data From Sacramento, CA
This page presents radiation air monitoring and air filter analysis data for Sacramento, CA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
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RadNet Air Data From Honolulu, HI
This page presents radiation air monitoring and air filter analysis data for Honolulu, HI from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
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RadNet Air Data From Houston, TX
This page presents radiation air monitoring and air filter analysis data for Houston, TX from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
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RadNet Air Data From Austin, TX
This page presents radiation air monitoring and air filter analysis data for Austin, TX from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
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RadNet Air Data From Orlando, FL
This page presents radiation air monitoring and air filter analysis data for Orlando, FL from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
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Virtual water trade and country vulnerability: A network perspective
Sartori, Martina; Schiavo, Stefano
2015-04-01
This work investigates the relationship between countries' participation in virtual water trade and their vulnerability to external shocks from a network perspective. In particular, we investigate whether (i) possible sources of local national crises may interact with the system, propagating through the network and affecting the other countries involved; (ii) the topological characteristics of the international agricultural trade network, translated into virtual water-equivalent flows, may favor countries' vulnerability to external crises. Our work contributes to the debate on the potential merits and risks associated with openness to trade in agricultural and food products. On the one hand, trade helps to ensure that even countries with limited water (and other relevant) resources have access to sufficient food and contribute to the global saving of water. On the other hand, there are fears that openness may increase the vulnerability to external shocks and thus make countries worse off. Here we abstract from political considerations about food sovereignty and independence from imports and focus instead on investigating whether the increased participation in global trade that the world has witnessed in the last 30 years has made the system more susceptible to large shocks. Our analysis reveals that: (i) the probability of larger supply shocks has not increased over time; (ii) the topological characteristics of the VW network are not such as to favor the systemic risk associated with shock propagation; and (iii) higher-order interconnections may reveal further important information about the structure of a network. Regarding the first result, fluctuations in output volumes, among the sources of shock analyzed here, are more likely to generate some instability. The first implication is that, on one side, past national or regional economic crises were not necessarily brought about or strengthened by global trade. The second, more remarkable, implication is that, on
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Verma, Shilp; Kampman, Doeke A.; van der Zaag, Pieter; Hoekstra, Arjen Ysbert
2008-01-01
Virtual water trade has been promoted as a tool to address national and regional water scarcity. In the context of international (food) trade, this concept has been applied with a view to optimize the flow of commodities considering the water endowments of nations. The concept states that water-rich
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Herting, Megan M.; Nagel, Bonnie J.
2012-01-01
In rodents, exercise increases hippocampal neurogenesis and allows for better learning and memory performance on water maze tasks. While exercise has also been shown to be beneficial for the brain and behavior in humans, no study has examined how exercise impacts spatial learning using a directly translational water maze task, or if these relationships exist during adolescence – a developmental period which the animal literature has shown to be especially vulnerable to exercise effects. In this study, we investigated the influence of aerobic fitness on hippocampal size and subsequent learning and memory, including visuospatial memory using a human analogue of the Morris Water Task, in 34 adolescents. Results showed that higher aerobic fitness predicted better learning on the virtual Morris Water Task and larger hippocampal volumes. No relationship between virtual Morris Water Task memory recall and aerobic fitness was detected. Aerobic fitness, however, did not relate to global brain volume, or verbal learning, which might suggest some specificity of the influence of aerobic fitness on the adolescent brain. This study provides a direct translational approach to the existing animal literature on exercise, as well as adds to the sparse research that exists on how aerobic exercise impacts the developing human brain and memory. PMID:22610054
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Herting, Megan M; Nagel, Bonnie J
2012-08-01
In rodents, exercise increases hippocampal neurogenesis and allows for better learning and memory performance on water maze tasks. While exercise has also been shown to be beneficial for the brain and behavior in humans, no study has examined how exercise impacts spatial learning using a directly translational water maze task, or if these relationships exist during adolescence--a developmental period which the animal literature has shown to be especially vulnerable to exercise effects. In this study, we investigated the influence of aerobic fitness on hippocampal size and subsequent learning and memory, including visuospatial memory using a human analogue of the Morris Water Task, in 34 adolescents. Results showed that higher aerobic fitness predicted better learning on the virtual Morris Water Task and larger hippocampal volumes. No relationship between virtual Morris Water Task memory recall and aerobic fitness was detected. Aerobic fitness, however, did not relate to global brain volume or verbal learning, which might suggest some specificity of the influence of aerobic fitness on the adolescent brain. This study provides a direct translational approach to the existing animal literature on exercise, as well as adds to the sparse research that exists on how aerobic exercise impacts the developing human brain and memory. Published by Elsevier B.V.
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New Desktop Virtual Reality Technology in Technical Education
Ausburn, Lynna J.; Ausburn, Floyd B.
2008-01-01
Virtual reality (VR) that immerses users in a 3D environment through use of headwear, body suits, and data gloves has demonstrated effectiveness in technical and professional education. Immersive VR is highly engaging and appealing to technically skilled young Net Generation learners. However, technical difficulty and very high costs have kept…
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Model and calculations for net infiltration
International Nuclear Information System (INIS)
Childs, S.W.; Long, A.
1992-01-01
In this paper a conceptual model for calculating net infiltration is developed and implemented. It incorporates the following important factors: viability of climate for the next 10,000 years, areal viability of net infiltration, and important soil/plant factors that affect the soil water budget of desert soils. Model results are expressed in terms of occurrence probabilities for time periods. In addition the variability of net infiltration is demonstrated both for change with time and differences among three soil/hydrologic units present at the site modeled
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Hydrogen Economy Model for Nearly Net-Zero Cities with Exergy Rationale and Energy-Water Nexus
Directory of Open Access Journals (Sweden)
Birol Kılkış
2018-05-01
Full Text Available The energy base of urban settlements requires greater integration of renewable energy sources. This study presents a “hydrogen city” model with two cycles at the district and building levels. The main cycle comprises of hydrogen gas production, hydrogen storage, and a hydrogen distribution network. The electrolysis of water is based on surplus power from wind turbines and third-generation solar photovoltaic thermal panels. Hydrogen is then used in central fuel cells to meet the power demand of urban infrastructure. Hydrogen-enriched biogas that is generated from city wastes supplements this approach. The second cycle is the hydrogen flow in each low-exergy building that is connected to the hydrogen distribution network to supply domestic fuel cells. Make-up water for fuel cells includes treated wastewater to complete an energy-water nexus. The analyses are supported by exergy-based evaluation metrics. The Rational Exergy Management Efficiency of the hydrogen city model can reach 0.80, which is above the value of conventional district energy systems, and represents related advantages for CO2 emission reductions. The option of incorporating low-enthalpy geothermal energy resources at about 80 °C to support the model is evaluated. The hydrogen city model is applied to a new settlement area with an expected 200,000 inhabitants to find that the proposed model can enable a nearly net-zero exergy district status. The results have implications for settlements using hydrogen energy towards meeting net-zero targets.
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KM3NeT is a large scale next-generation neutrino telescope located in the deep waters of the Mediterranean Sea, optimized for the discovery of galactic neutrino sources emitting in the TeV energy region.
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Projections of Virtual Water Trade Under Agricultural Policy Scenarios in China
Dalin, C.; Hanasaki, N.; Qiu, H.; Mauzerall, D. L.; Rodriguez-Iturbe, I.
2014-12-01
China's economic growth is expected to continue into the next decades, accompanied by a sustained urbanization and industrialization. The associated increase in demand for land, water resources and rich foods will deepen the challenge to sustainably feed the population and balance environmental and agricultural policies. In previous work, Inner Mongolia was identified as a target province for trade or agricultural policies aimed at water-use efficiency improvements, due to its large production relying on particularly significant irrigation water use. In addition, water scarcity issues may arises in the greater Beijing area, which represents the largest urban area of arid Northern China. Increasing residential and industrial water demand in this region may lead to fewer available water for irrigation. For these reasons, it is important to estimate the impacts of specific policies aiming at reducing excessive water use for crop production in Inner Mongolia, as well as exploring ways to mitigate pressure on water resources in dry urban areas. In this study, we use socio-economic projections to assess the future state of China's virtual water trade (VWT) network. We then quantify the effects of agricultural policies on the national VWT system and on the efficiency of food trade in terms of water resources. This study addresses the following questions: (1) How future socio-economic changes will affect China's food trade and associated water transfers? (2) To which extent localized reductions of irrigated area can decrease agricultural water use while maintaining national food security? (3) How would these policies affect China's domestic and international VWT network and induced water resources savings (losses)?
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RadNet Air Data From Fort Smith, AR
This page presents radiation air monitoring and air filter analysis data for Fort Smith, AR from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
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RadNet Air Data From Little Rock, AR
This page presents radiation air monitoring and air filter analysis data for Little Rock, AR from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
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RadNet Air Data From Mason City, IA
This page presents radiation air monitoring and air filter analysis data for Mason City, IA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
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Novotny, V
2011-01-01
This article discusses the link between water conservation, reclamation, reuse and energy use as related to the goal of achieving the net zero carbon emission footprint in future sustainable cities. It defines sustainable ecocities and outlines quantitatively steps towards the reduction of energy use due to water and used water flows, management and limits in linear and closed loop water/stormwater/wastewater management systems. The three phase water energy nexus diagram may have a minimum inflection point beyond which reduction of water demand may not result in a reduction of energy and carbon emissions. Hence, water conservation is the best alternative solution to water shortages and minimizing the carbon footprint. A marginal water/energy chart is developed and proposed to assist planners in developing future ecocities and retrofitting older communities to achieve sustainability.
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Directory of Open Access Journals (Sweden)
A. J. Dolman
2004-01-01
Full Text Available Observations of the net ecosystem exchange of water and CO2 were made during two seasons in 2000 and 2001 above a Larch forest in Far East Siberia (Yakutsk. The measurements were obtained by eddy correlation. There is a very sharply pronounced growing season of 100 days when the forest is leaved. Maximum half hourly uptake rates are 18 µmol m-2 s-1; maximum respiration rates are 5 µmol m-2 s-1. Net annual sequestration of carbon was estimated at 160 gCm-2 in 2001. Applying no correction for low friction velocities added 60 g C m-2. The net carbon exchange of the forest was extremely sensitive to small changes in weather that may switch the forest easily from a sink to a source, even in summer. June was the month with highest uptake in 2001. The average evaporation rate of the forest approached 1.46 mm day-1 during the growing season, with peak values of 3 mm day-1 with an estimated annual evaporation of 213 mm, closely approaching the average annual rainfall amount. 2001 was a drier year than 2000 and this is reflected in lower evaporation rates in 2001 than in 2000. The surface conductance of the forest shows a marked response to increasing atmospheric humidity deficits. This affects the CO2 uptake and evaporation in a different manner, with the CO2 uptake being more affected. There appears to be no change in the relation between surface conductance and net ecosystem uptake normalized by the atmospheric humidity deficit at the monthly time scale. The response to atmospheric humidity deficit is an efficient mechanism to prevent severe water loss during the short intense growing season. The associated cost to the sequestration of carbon may be another explanation for the slow growth of these forests in this environment.
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International Nuclear Information System (INIS)
Tellez Guio, Patricia; Boschell Villamarin, Francisco; Tobon Marin, Conrado
2005-01-01
Hydrologic simulation is a technique, which allows us to understand the relationships among hydrological, biological and ecological variables in an ecosystem. In this research, the FORHYD model is used to simulate the net precipitation and the water intercepted by the canopies of a mature forest, a 30-year old secondary forest, an 18-year old secondary forest, a 5-year old secondary forest, and a shifting cultivation plot, all located in Colombia's amazonia. The model calculates the water budget of the canopy by using the precipitation rates, canopy drainage and evaporation of the water intercepted by the canopy. This paper is the second one in a series of papers reporting the results of the research on the simulation of the hydrological fluxes in three different land use types of Colombian amazonia. The research was carried out in middle Caqueta of Colombian amazonia (northwest amazon basin). The FORHYD model was calibrated and validated by using field observations of the climate, net precipitation (PT), thoughtful (TH) and stem flow (ST), which were monitored during a period of 15 months from March 2001 to June 2002. These observations were used as both input variables and diagnostic variables to probe the model's precision to simulate field observations. Results showed that FORHYD simulates with a good precision the net precipitation and the evaporation of the water intercepted by the canopy. However, the model's precision depends on a good parameterization, which in turn depends on a good database of field observations. The model is a good tool for simulating the hydrological cycle and can be used to simulate critical scenarios of climate variability
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Shearrow, Charles A.
1999-01-01
One of the identified goals of EM3 is to implement virtual manufacturing by the time the year 2000 has ended. To realize this goal of a true virtual manufacturing enterprise the initial development of a machinability database and the infrastructure must be completed. This will consist of the containment of the existing EM-NET problems and developing machine, tooling, and common materials databases. To integrate the virtual manufacturing enterprise with normal day to day operations the development of a parallel virtual manufacturing machinability database, virtual manufacturing database, virtual manufacturing paradigm, implementation/integration procedure, and testable verification models must be constructed. Common and virtual machinability databases will include the four distinct areas of machine tools, available tooling, common machine tool loads, and a materials database. The machine tools database will include the machine envelope, special machine attachments, tooling capacity, location within NASA-JSC or with a contractor, and availability/scheduling. The tooling database will include available standard tooling, custom in-house tooling, tool properties, and availability. The common materials database will include materials thickness ranges, strengths, types, and their availability. The virtual manufacturing databases will consist of virtual machines and virtual tooling directly related to the common and machinability databases. The items to be completed are the design and construction of the machinability databases, virtual manufacturing paradigm for NASA-JSC, implementation timeline, VNC model of one bridge mill and troubleshoot existing software and hardware problems with EN4NET. The final step of this virtual manufacturing project will be to integrate other production sites into the databases bringing JSC's EM3 into a position of becoming a clearing house for NASA's digital manufacturing needs creating a true virtual manufacturing enterprise.
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Directory of Open Access Journals (Sweden)
Le Qi
2018-05-01
Full Text Available In this study, we investigated the greenhouse gas emission under different application of biochar in the conditions of continuous flooding and water-saving irrigation in paddy fields, whereas, plant and soil carbon sequestration were considered in the calculation of net greenhouse gas emissions. The emission rates of methane (CH4, carbon dioxide (CO2, and nitrous oxide (N2O gases were simultaneously monitored once every 7–10 days using the closed-chamber method. As a whole, the net greenhouse gas emission in the water-saving irrigation was more than that of the continuous flooding irrigation conditions. Compared with the water-saving irrigation, the continuous flooding irrigation significantly increased the CH4 in the control (CK and chemical fertilizer treatments (NPK. The CO2 emissions increased in each treatment of the water-saving irrigation condition, especially in the chemical fertilizer treatments (NPKFW. Similarly, the soil N2O emission was very sensitive to the water-saving irrigation condition. An interesting finding is that the biochar application in soils cut down the soil N2O emission more significantly than NPKFW in the water-saving irrigation condition while the effect of biochar increased under the continuous flooding irrigation condition.
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Water footprint of Jing-Jin-Ji urban agglomeration in China
Zhao, D.
2017-12-01
A rapidly expanding economy and increasing water demand for economic production is placing enormous stress on water quantity and aquatic environment in Northern China, especially the so-called Jing-Jin-Ji (Beijing-Tianjin-Hebei) urban agglomeration. Several studies have focused on energy consumption, air pollution, CO2 emissions and regional blue water footprint (WF) following release of the Jing-Jin-Ji Integration Strategy by the China government. However, a comprehensive assessment distinguishing blue, green and grey WF amongst different industrial sectors, ascertaining how WF transfers internally and beyond the region and final demand consumption is not available. In this study, we quantified the WF and virtual water flow on a sectoral basis for the year 2010 through coupling the multi-regional input-output model (MRIO) with WF assessment. The results showed that Beijing and Tianjin are net importers of green, blue and grey water from Hebei and other provinces to support their needs. Conversely, Hebei exports all WF colors to Beijing, Tianjin and other provinces in China, more than 60% of WF is transferred as virtual water. For the overall Jing-Jin-Ji region a small amount of blue water (2,086 million m3) is exported, but huge amounts of green water (15,573 million m3) and grey water (30,620 million m3) are outsourced. A "Virtual Water Strategy" is one measure which could alleviate water stress at the regional scale, with consideration of financial compensation from water receiving regions made to water supplying regions for achieving water management targets. We also found that physical water transfer to Jing-Jin-Ji could not balance virtual blue water exports. Our research suggests that a continuation of an export-based economic development model will worsen Hebei's water stress. Reducing the dependency of Hebei's sectoral economy on export of water intensive and low value added agricultural products may be one strategy to reduce the pressure on regional water
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Native on the net indigenous and diasporic peoples in the virtual age
Landzelius, Kyra; Shi, Xianglin
2004-01-01
Exploring the influence of the Internet on the lives of indigenous and diasporic peoples, Kyra Landzelius leads a team of expert anthropologists and ethnographers who go on-site and on-line to explore how a diverse range of indigenous and transnational diasporic communities actually use the Internet. From the Taino Indians of the Caribbean, the U'wa of the Amazon rainforest, and the Tunomans and Assyrians of Iraq, to the Tingas and Zapatistas, Native on the Net is a lively and intriguing exploration of how new technologies have enabled these previously isolated peoples to reach new levels of communication and community: creating new communities online, confronting global corporations, or even challenging their own native traditions. Featuring case studies ranging from the Artic to the Australian outback, this book addresses important recurrent themes, such as the relationship between identity and place, community, traditional cultures and the nature of the 'indigenous'. Native on the Net is a unique contribut...
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Modeling the Economic Feasibility of Large-Scale Net-Zero Water Management: A Case Study.
Guo, Tianjiao; Englehardt, James D; Fallon, Howard J
While municipal direct potable water reuse (DPR) has been recommended for consideration by the U.S. National Research Council, it is unclear how to size new closed-loop DPR plants, termed "net-zero water (NZW) plants", to minimize cost and energy demand assuming upgradient water distribution. Based on a recent model optimizing the economics of plant scale for generalized conditions, the authors evaluated the feasibility and optimal scale of NZW plants for treatment capacity expansion in Miami-Dade County, Florida. Local data on population distribution and topography were input to compare projected costs for NZW vs the current plan. Total cost was minimized at a scale of 49 NZW plants for the service population of 671,823. Total unit cost for NZW systems, which mineralize chemical oxygen demand to below normal detection limits, is projected at ~$10.83 / 1000 gal, approximately 13% above the current plan and less than rates reported for several significant U.S. cities.
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Net CO2 and water exchanges of trees and grasses in a semi-arid region (Gourma, Mali)
Le Dantec, Valérie; Kergoat, Laurent; Timouk, Franck; Hiernaux, Pierre; Mougin, Eric
2010-05-01
An improved understanding of plant and soil processes is critical to predict land surface-atmosphere water exchanges, especially in semi-arid environments, where knowledge is still severely lacking. Within the frame of the African Monsoon Multidisciplinary Project (AMMA), eddy covariance and sapflow stations have been installed to document the intensity, the temporal variability and the main drivers of net CO2 fluxes, water fluxes and contribution of the trees to these fluxes in a pastoral Sahelian landscape. Indeed, although the importance of vegetation in the West African monsoon system has long been postulated, extremely few data were available sofar to test and develop land surface models. In particular, data documenting seasonal and inter-annual dynamics of vegetation/atmosphere exchanges did not exist at 15° N in West Africa before AMMA. The site is located in the Gourma, Mali. Vegetation in this area is sparse and mainly composed of annual grasses and forbs, and trees. Vegetation is organized according to soil type and lateral water redistribution, with bare soil with scattered trees on shallow soils and rocky outcrops (35% of the area), annual grasses and scattered trees on sandy soils (65% of the area), and more dense canopies of grasses and trees growing in valley bottoms over clay soil. To quantify tree transpiration in the overall evapotranspiration flux, sapflow measurements, associated to soil moisture measurements, have been conducted on the main tree species (Acacia senegal, A. seyal, A. raddiana, Combretum glutinosum, Balanites aegyptiaca) in a grassland site and in an open forest site, where eddy covariance fluxes measured the total flux. Using this dataset, we have studied the effects of plant diversity on carbon and water fluxes at the foot-print scale and seasonal dynamics of fluxes due to plant phenology and variations of soil water content (SWC). Carbon fluxes were documented as well, over two years. NEE was close to 0 during the dry season
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Verma, Shilp; Kampman, Doeke A.; van der Zaag, Pieter; Hoekstra, Arjen Ysbert
2009-01-01
Virtual water trade has been promoted as a tool to address national and regional water scarcity. In the context of international (food) trade, this concept has been applied with a view to optimize the flow of commodities considering the water endowments of nations. The concept states that water rich
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Net-bottom Cage Inserts for Water Bird Casualties
Directory of Open Access Journals (Sweden)
Jackie Belle
2017-10-01
Full Text Available My Bright Idea is a net-bottomed cage insert, which is used to support pelagic avian casualties. The idea was designed and modified by the International Bird Rescue in California (Bird Rescue.
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VIRTUAL NETWORK COMMUNICATION AND ITS IMPACT ON INTERPERSONAL RELATIONS
Directory of Open Access Journals (Sweden)
Сергей Николаевич Хуторной
2013-08-01
Full Text Available The Internet was playing an increasing role in human life. Increasingly popular sites, where visitors can interact with other visitors through this site. Becoming popular communication "online", partially displacing the real-мире. There arises a problem of Internet addiction, or dependence on the Internet, which includes not only the dependence on virtual communication in social networks, but also addiction to gambling, online games, electronic purchases, and so on. Virtual reality acts not only as an intermediary virtual communication, but also significantly affect the nature, means and methods of communication, which ultimately has a significant effect on identity, often negatively, transforming it. The article dedicated to the analysis of intercourse in virtual reality. The specification of net communication in comparing of real social communication is researching. The concept of Internet addicion is examined.DOI: http://dx.doi.org/10.12731/2218-7405-2013-6-9
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Directory of Open Access Journals (Sweden)
S.-H. Lee
2016-10-01
Full Text Available This study aims to analyze the characteristics of global virtual water trade (GVWT, such as the connectivity of each trader, vulnerable importers, and influential countries, using degree and eigenvector centrality during the period 2006–2010. The degree centrality was used to measure the connectivity, and eigenvector centrality was used to measure the influence on the entire GVWT network. Mexico, Egypt, China, the Republic of Korea, and Japan were classified as vulnerable importers, because they imported large quantities of virtual water with low connectivity. In particular, Egypt had a 15.3 Gm3 year−1 blue water saving effect through GVWT: the vulnerable structure could cause a water shortage problem for the importer. The entire GVWT network could be changed by a few countries, termed "influential traders". We used eigenvector centrality to identify those influential traders. In GVWT for food crops, the USA, Russian Federation, Thailand, and Canada had high eigenvector centrality with large volumes of green water trade. In the case of blue water trade, western Asia, Pakistan, and India had high eigenvector centrality. For feed crops, the green water trade in the USA, Brazil, and Argentina was the most influential. However, Argentina and Pakistan used high proportions of internal water resources for virtual water export (32.9 and 25.1 %; thus other traders should carefully consider water resource management in these exporters.
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Lee, Sang-Hyun; Mohtar, Rabi H.; Choi, Jin-Yong; Yoo, Seung-Hwan
2016-10-01
This study aims to analyze the characteristics of global virtual water trade (GVWT), such as the connectivity of each trader, vulnerable importers, and influential countries, using degree and eigenvector centrality during the period 2006-2010. The degree centrality was used to measure the connectivity, and eigenvector centrality was used to measure the influence on the entire GVWT network. Mexico, Egypt, China, the Republic of Korea, and Japan were classified as vulnerable importers, because they imported large quantities of virtual water with low connectivity. In particular, Egypt had a 15.3 Gm3 year-1 blue water saving effect through GVWT: the vulnerable structure could cause a water shortage problem for the importer. The entire GVWT network could be changed by a few countries, termed "influential traders". We used eigenvector centrality to identify those influential traders. In GVWT for food crops, the USA, Russian Federation, Thailand, and Canada had high eigenvector centrality with large volumes of green water trade. In the case of blue water trade, western Asia, Pakistan, and India had high eigenvector centrality. For feed crops, the green water trade in the USA, Brazil, and Argentina was the most influential. However, Argentina and Pakistan used high proportions of internal water resources for virtual water export (32.9 and 25.1 %); thus other traders should carefully consider water resource management in these exporters.
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Mezbahuddin, Mohammad; Grant, Robert F.; Flanagan, Lawrence B.
2017-12-01
Water table depth (WTD) effects on net ecosystem CO2 exchange of boreal peatlands are largely mediated by hydrological effects on peat biogeochemistry and the ecophysiology of peatland vegetation. The lack of representation of these effects in carbon models currently limits our predictive capacity for changes in boreal peatland carbon deposits under potential future drier and warmer climates. We examined whether a process-level coupling of a prognostic WTD with (1) oxygen transport, which controls energy yields from microbial and root oxidation-reduction reactions, and (2) vascular and nonvascular plant water relations could explain mechanisms that control variations in net CO2 exchange of a boreal fen under contrasting WTD conditions, i.e., shallow vs. deep WTD. Such coupling of eco-hydrology and biogeochemistry algorithms in a process-based ecosystem model, ecosys, was tested against net ecosystem CO2 exchange measurements in a western Canadian boreal fen peatland over a period of drier-weather-driven gradual WTD drawdown. A May-October WTD drawdown of ˜ 0.25 m from 2004 to 2009 hastened oxygen transport to microbial and root surfaces, enabling greater microbial and root energy yields and peat and litter decomposition, which raised modeled ecosystem respiration (Re) by 0.26 µmol CO2 m-2 s-1 per 0.1 m of WTD drawdown. It also augmented nutrient mineralization, and hence root nutrient availability and uptake, which resulted in improved leaf nutrient (nitrogen) status that facilitated carboxylation and raised modeled vascular gross primary productivity (GPP) and plant growth. The increase in modeled vascular GPP exceeded declines in modeled nonvascular (moss) GPP due to greater shading from increased vascular plant growth and moss drying from near-surface peat desiccation, thereby causing a net increase in modeled growing season GPP by 0.39 µmol CO2 m-2 s-1 per 0.1 m of WTD drawdown. Similar increases in GPP and Re caused no significant WTD effects on modeled
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Alebregtse, N. C.|info:eu-repo/dai/nl/345704304; de Swart, H. E.|info:eu-repo/dai/nl/073449725
2016-01-01
Tidal propagation in, and division of net water transport over different channels in an estuarine network are analyzed using a newly developed idealized model. The water motion in this model is governed by the cross-sectionally averaged shallow water equations and is forced by tides at the seaward
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Morikawa, Y.; Murata, K. T.; Watari, S.; Kato, H.; Yamamoto, K.; Inoue, S.; Tsubouchi, K.; Fukazawa, K.; Kimura, E.; Tatebe, O.; Shimojo, S.
2010-12-01
Main methodologies of Solar-Terrestrial Physics (STP) so far are theoretical, experimental and observational, and computer simulation approaches. Recently "informatics" is expected as a new (fourth) approach to the STP studies. Informatics is a methodology to analyze large-scale data (observation data and computer simulation data) to obtain new findings using a variety of data processing techniques. At NICT (National Institute of Information and Communications Technology, Japan) we are now developing a new research environment named "OneSpaceNet". The OneSpaceNet is a cloud-computing environment specialized for science works, which connects many researchers with high-speed network (JGN: Japan Gigabit Network). The JGN is a wide-area back-born network operated by NICT; it provides 10G network and many access points (AP) over Japan. The OneSpaceNet also provides with rich computer resources for research studies, such as super-computers, large-scale data storage area, licensed applications, visualization devices (like tiled display wall: TDW), database/DBMS, cluster computers (4-8 nodes) for data processing and communication devices. What is amazing in use of the science cloud is that a user simply prepares a terminal (low-cost PC). Once connecting the PC to JGN2plus, the user can make full use of the rich resources of the science cloud. Using communication devices, such as video-conference system, streaming and reflector servers, and media-players, the users on the OneSpaceNet can make research communications as if they belong to a same (one) laboratory: they are members of a virtual laboratory. The specification of the computer resources on the OneSpaceNet is as follows: The size of data storage we have developed so far is almost 1PB. The number of the data files managed on the cloud storage is getting larger and now more than 40,000,000. What is notable is that the disks forming the large-scale storage are distributed to 5 data centers over Japan (but the storage
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Design and Test of the Cross-Format Schema Protocol (XFSP) for Networked Virtual Environments
National Research Council Canada - National Science Library
Serin, Ekrem
2003-01-01
A Networked Virtual Environment (Net-VE) is a distributed software system in which multiple users interact with each other in real time even though these users may be located around the world Zyda 99...
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Directory of Open Access Journals (Sweden)
M. Mezbahuddin
2017-12-01
Full Text Available Water table depth (WTD effects on net ecosystem CO2 exchange of boreal peatlands are largely mediated by hydrological effects on peat biogeochemistry and the ecophysiology of peatland vegetation. The lack of representation of these effects in carbon models currently limits our predictive capacity for changes in boreal peatland carbon deposits under potential future drier and warmer climates. We examined whether a process-level coupling of a prognostic WTD with (1 oxygen transport, which controls energy yields from microbial and root oxidation–reduction reactions, and (2 vascular and nonvascular plant water relations could explain mechanisms that control variations in net CO2 exchange of a boreal fen under contrasting WTD conditions, i.e., shallow vs. deep WTD. Such coupling of eco-hydrology and biogeochemistry algorithms in a process-based ecosystem model, ecosys, was tested against net ecosystem CO2 exchange measurements in a western Canadian boreal fen peatland over a period of drier-weather-driven gradual WTD drawdown. A May–October WTD drawdown of ∼ 0.25 m from 2004 to 2009 hastened oxygen transport to microbial and root surfaces, enabling greater microbial and root energy yields and peat and litter decomposition, which raised modeled ecosystem respiration (Re by 0.26 µmol CO2 m−2 s−1 per 0.1 m of WTD drawdown. It also augmented nutrient mineralization, and hence root nutrient availability and uptake, which resulted in improved leaf nutrient (nitrogen status that facilitated carboxylation and raised modeled vascular gross primary productivity (GPP and plant growth. The increase in modeled vascular GPP exceeded declines in modeled nonvascular (moss GPP due to greater shading from increased vascular plant growth and moss drying from near-surface peat desiccation, thereby causing a net increase in modeled growing season GPP by 0.39 µmol CO2 m−2 s−1 per 0.1 m of WTD drawdown. Similar increases in
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[Zr(NEtMe)2(guan-NEtMe)2] as a novel ALD precursor: ZrO2 film growth and mechanistic studies
Blanquart, T.; Niinistö, J.; Aslam, N.; Banerjee, M.; Tomczak, Y.; Gavagnin, M.; Longo, V.; Puukilainen, E.; Wanzenboeck, H.D.; Kessels, W.M.M.; Devi, A.; Hoffmann-Eifert, S.; Ritala, M.; Leskelä, M.
2013-01-01
[Zr(NEtMe)2(guan-NEtMe2)2], a recently developed compound, was investigated as a novel precursor for the atomic layer deposition (ALD) of ZrO2. With water as the oxygen source, the growth rate remained constant over a wide temperature range, whereas with ozone the growth rate increased steadily with
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The water footprint of agricultural products in European river basins
International Nuclear Information System (INIS)
Vanham, D; Bidoglio, G
2014-01-01
This work quantifies the agricultural water footprint (WF) of production (WF prod, agr ) and consumption (WF cons, agr ) and the resulting net virtual water import (netVW i, agr ) of 365 European river basins for a reference period (REF, 1996–2005) and two diet scenarios (a healthy diet based upon food-based dietary guidelines (HEALTHY) and a vegetarian (VEG) diet). In addition to total (tot) amounts, a differentiation is also made between the green (gn), blue (bl) and grey (gy) components. River basins where the REF WF cons, agr, tot exceeds the WF prod, agr, tot (resulting in positive netVW i, agr, tot values), are found along the London–Milan axis. These include the Thames, Scheldt, Meuse, Seine, Rhine and Po basins. River basins where the WF prod, agr, tot exceeds the WF cons, agr, tot are found in Western France, the Iberian Peninsula and the Baltic region. These include the Loire, Ebro and Nemunas basins. Under the HEALTHY diet scenario, the WF cons, agr, tot of most river basins decreases (max −32%), although it was found to increase in some basins in northern and eastern Europe. This results in 22 river basins, including the Danube, shifting from being net VW importers to being net VW exporters. A reduction (max −46%) in WF cons, agr, tot is observed for all but one river basin under the VEG diet scenario. In total, 50 river basins shift from being net VW importers to being net exporters, including the Danube, Seine, Rhone and Elbe basins. Similar observations are made when only the gn + bl and gn components are assessed. When analysing only the bl component, a different river basin pattern is observed. (letters)
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Velpuri, Naga Manohar; Senay, Gabriel B.; Rowland, James; Verdin, James P.; Alemu, Henok; Melesse, Assefa M.; Abtew, Wossenu; Setegn, Shimelis G.
2014-01-01
Continental Africa has the highest volume of water stored in wetlands, large lakes, reservoirs, and rivers, yet it suffers from problems such as water availability and access. With climate change intensifying the hydrologic cycle and altering the distribution and frequency of rainfall, the problem of water availability and access will increase further. Famine Early Warning Systems Network (FEWS NET) funded by the United States Agency for International Development (USAID) has initiated a large-scale project to monitor small to medium surface water points in Africa. Under this project, multisource satellite data and hydrologic modeling techniques are integrated to monitor several hundreds of small to medium surface water points in Africa. This approach has been already tested to operationally monitor 41 water points in East Africa. The validation of modeled scaled depths with field-installed gauge data demonstrated the ability of the model to capture both the spatial patterns and seasonal variations. Modeled scaled estimates captured up to 60 % of the observed gauge variability with a mean root-mean-square error (RMSE) of 22 %. The data on relative water level, precipitation, and evapotranspiration (ETo) for water points in East and West Africa were modeled since 1998 and current information is being made available in near-real time. This chapter presents the approach, results from the East African study, and the first phase of expansion activities in the West Africa region. The water point monitoring network will be further expanded to cover much of sub-Saharan Africa. The goal of this study is to provide timely information on the water availability that would support already established FEWS NET activities in Africa. This chapter also presents the potential improvements in modeling approach to be implemented during future expansion in Africa.
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On the Role of Hyper-arid Regions within the Virtual Water Trade Network
Aggrey, James; Alshamsi, Aamena; Molini, Annalisa
2016-04-01
Climate change, economic development, and population growth are bound to increasingly impact global water resources, posing a significant threat to the sustainable development of arid regions, where water consumption highly exceeds the natural carrying capacity, population growth rate is high, and climate variability is going to impact both water consumption and availability. Virtual Water Trade (VWT) - i.e. the international trade network of water-intensive products - has been proposed as a possible solution to optimize the allocation of water resources on the global scale. By increasing food availability and lowering food prices it may in fact help the rapid development of water-scarce regions. The structure of the VWT network has been analyzed by a number of authors both in connection with trade policies, socioeconomic constrains and agricultural efficiency. However a systematic analysis of the structure and the dynamics of the VWT network conditional to aridity, climatic forcing and energy availability, is still missing. Our goal is hence to analyze the role of arid and hyper-arid regions within the VWN under diverse climatic, demographic, and energy constraints with an aim to contribute to the ongoing Energy-Water-Food nexus discussion. In particular, we focus on the hyper-arid lands of the Arabian Peninsula, the role they play in the global network and the assessment of their specific criticalities, as reflected in the VWN resilience.
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International Nuclear Information System (INIS)
McCoy, E.L.; Boersma, L.; Ekasingh, M.
1990-01-01
The influence of water stress at two soil temperatures on allocation of net photoassimilated carbon in soybean (Glycine max [L.] Merr.) was investigated using compartmental analysis. The experimental phase employed classical 14 C labeling methodology with plants equilibrated at soil water potentials of -0.04, -0.25 and -0.50 MPa; and soil temperatures of 25 and 10C. Carbon immobilization in the shoot apex generally followed leaf elongation rates with decreases in both parameters at increasing water stress at both soil temperatures. However, where moderate water stress resulted in dramatic declines in leaf elongation rates, carbon immobilization rates were sharply decreased only at severe water stress levels. Carbon immobilization was decreased in the roots and nodules of the nonwater stressed treatment by the lower soil temperature. This relation was reversed with severe water stress, and carbon immobilization in the roots and nodules was increased at the lower soil temperature. Apparently, the increased demand for growth and/or carbon storage in these tissues with increased water stress overcame the low soil temperature limitations. Both carbon pool sizes and partitioning of carbon to the sink tissues increased with moderate water stress at 25C soil temperature. Increased pool sizes were consistent with whole plant osmotic adjustment at moderate water stress. Increased partitioning to the sinks was consistent with carbon translocation processes being less severely influenced by water stress than is photosynthesis
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Worm, G.I.M.; Kelderman, J.P.; Lapikas, T.; Van der Helm, A.W.C.; Van Schagen, K.M.; Rietveld, L.C.
2012-01-01
This research deals with the contribution of process simulation models to the factory acceptance test (FAT) of process automation (PA) software of drinking water treatment plants. Two test teams tested the same piece of modified PA-software. One team used an advanced virtual commissioning (AVC)
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International Nuclear Information System (INIS)
Hevesi, J.A.; Flint, A.L.; Flint, L.E.
2002-01-01
A three-dimensional ground-water flow model has been developed to evaluate the Death Valley regional flow system, which includes ground water beneath the Nevada Test Site. Estimates of spatially distributed net infiltration and recharge are needed to define upper boundary conditions. This study presents a preliminary application of a conceptual and numerical model of net infiltration. The model was developed in studies at Yucca Mountain, Nevada, which is located in the approximate center of the Death Valley ground-water flow system. The conceptual model describes the effects of precipitation, runoff, evapotranspiration, and redistribution of water in the shallow unsaturated zone on predicted rates of net infiltration; precipitation and soil depth are the two most significant variables. The conceptual model was tested using a preliminary numerical model based on energy- and water-balance calculations. Daily precipitation for 1980 through 1995, averaging 202 millimeters per year over the 39,556 square kilometers area of the ground-water flow model, was input to the numerical model to simulate net infiltration ranging from zero for a soil thickness greater than 6 meters to over 350 millimeters per year for thin soils at high elevations in the Spring Mountains overlying permeable bedrock. Estimated average net infiltration over the entire ground-water flow model domain is 7.8 millimeters per year. To evaluate the application of the net-infiltration model developed on a local scale at Yucca Mountain, to net-infiltration estimates representing the magnitude and distribution of recharge on a regional scale, the net-infiltration results were compared with recharge estimates obtained using empirical methods. Comparison of model results with previous estimates of basinwide recharge suggests that the net-infiltration estimates obtained using this model may overestimate recharge because of uncertainty in modeled precipitation, bedrock permeability, and soil properties for
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Stroosnijder, L.; Lascano, R. J.; Newton, R. W.; Vanbavel, C. H. M.
1984-01-01
A general method to use a time series of L-band emissivities as an input to a hydrological model for continuously monitoring the net rainfall and evaporation as well as the water content over the entire soil profile is proposed. The model requires a sufficiently accurate and general relation between soil emissivity and surface moisture content. A model which requires the soil hydraulic properties as an additional input, but does not need any weather data was developed. The method is shown to be numerically consistent.
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Pérez-Pérez, J G; Syvertsen, J P; Botía, P; García-Sánchez, F
2007-08-01
Since salinity and drought stress can occur together, an assessment was made of their interacting effects on leaf water relations, osmotic adjustment and net gas exchange in seedlings of the relatively chloride-sensitive Carrizo citrange, Citrus sinensis x Poncirus trifoliata. Plants were fertilized with nutrient solution with or without additional 100 mm NaCl (salt and no-salt treatments). After 7 d, half of the plants were drought stressed by withholding irrigation water for 10 d. Thus, there were four treatments: salinized and non-salinized plants under drought-stress or well-watered conditions. After the drought period, plants from all stressed treatments were re-watered with nutrient solution without salt for 8 d to study recovery. Leaf water relations, gas exchange parameters, chlorophyll fluorescence, proline, quaternary ammonium compounds and leaf and root concentrations of Cl(-) and Na(+) were measured. Salinity increased leaf Cl(-) and Na(+) concentrations and decreased osmotic potential (Psi(pi)) such that leaf relative water content (RWC) was maintained during drought stress. However, in non-salinized drought-stressed plants, osmotic adjustment did not occur and RWC decreased. The salinity-induced osmotic adjustment was not related to any accumulation of proline, quaternary ammonium compounds or soluble sugars. Net CO(2) assimilation rate (A(CO2)) was reduced in leaves from all stressed treatments but the mechanisms were different. In non-salinized drought-stressed plants, lower A(CO2) was related to low RWC, whereas in salinized plants decreased A(CO2) was related to high levels of leaf Cl(-) and Na(+). A(CO2) recovered after irrigation in all the treatments except in previously salinized drought-stressed leaves which had lower RWC and less chlorophyll but maintained high levels of Cl(-), Na(+) and quaternary ammonium compounds after recovery. High leaf levels of Cl(-) and Na(+) after recovery apparently came from the roots. Plants preconditioned by
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WE-NET Hydrogen Energy Symposium proceedings; WE-NET suiso energy symposium koen yokoshu
Energy Technology Data Exchange (ETDEWEB)
NONE
1999-02-24
The research and development of WE-NET (World Energy Network) was started in 1993 as a NEDO (New Energy and Industrial Technology Development Organization) project in the New Sunshine Program of Agency of Industrial Science and Technology, Ministry of International Trade and Industry, and aims to contribute to the improvement of global environment and to ease the difficult energy supply/demand situation. The ultimate goal of WE-NET is the construction of a global-scale clean energy network in which hydrogen will be produced from renewable energies such as water and sunshine for distribution to energy consuming locations. Experts are invited to the Symposium from the United States, Germany, and Canada. Information is collected from the participants on hydrogen energy technology development in the three countries, the result of the Phase I program of WE-NET is presented to hydrogen energy scientists in Japan, and views and opinions on the project are collected from them. Accommodated in the above-named publication are 30 essays and three special lectures delivered at the Symposium. (NEDO)
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Vythilingam, I; Zainal, A R; Hamidah, T
1999-03-01
Two formulations of lambda-cyhalothrin (EC-Emulsion concentrate and MC-Microencapsulated) were impregnated into bednets made of polyethylene and polyester. The nets were treated at a dosage of 15 mg/m2. For bioassay of insecticidal efficacy, female Anopheles maculatus and Aedes aegypti were exposed to the nets for two minutes and mortality was scored 24 hours later. The nets were also tested after repeated washings with water and with soap and water. Microencapsulated (2.5CS) formulation was more effective than emulsion concentrate (2.5EC) formulation on both net materials--polyethylene and polyester. Repeated washing with water and soap reduces the efficacy of all bednet treatment combinations. Microencapsulated formulation on polyethylene gave best results; it could sustain up to five washes with water and two with soap and water.
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Directory of Open Access Journals (Sweden)
Débora Del Puppo
Full Text Available ABSTRACT: Two experiments were conducted to evaluate the effects of reducing dietary crude protein (CP, based on the ideal protein concept for Nile tilapia reared in net pens. The experimental (isocaloric, isocalcium, and isophosphoric diets were formulated to contain 270, 300, 330, and 360g kg-1 CP. In experiment 1, 4320 Nile tilapia (13.5±0.82g were used to evaluate the performance and hematological parameters. The experimental design was completely randomized and the fish were distributed in 24 net pens (1.0m3, with four diets, six replicates, and 180 fishes per experimental unit. In experiment 2, 40 Nile tilapia (22.5±0.56g were used to evaluate the ammonia excretion. Fish were distributed in 40 aquaria (3.0L, with one fish per aquarium (n=10. No protein reduction effect was observed in feed intake and the hematocrit and hemoglobin values. Regarding the statistic models used in the present study, difference was observed between CP values. The optimal level estimated by the quadratic equation first interception with the linear response plateau (LRP as a response to CP changes in the diet was determined for weight gain (324.3g kg-1 and feed conversion (317.8g kg-1. After reduction in the CP levels, a linear reduction was observed in the ammonia excretion in water. Based on the ideal protein concept for Nile tilapia reared in net pens, reducing the CP levels in the diets is possible, without change in the performance and hematological parameters, and with a reduction in the levels of ammonia excretion in water, since amino acids are supplemented.
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CellNet: Network Biology Applied to Stem Cell Engineering
Cahan, Patrick; Li, Hu; Morris, Samantha A.; da Rocha, Edroaldo Lummertz; Daley, George Q.; Collins, James J.
2014-01-01
SUMMARY Somatic cell reprogramming, directed differentiation of pluripotent stem cells, and direct conversions between differentiated cell lineages represent powerful approaches to engineer cells for research and regenerative medicine. We have developed CellNet, a network biology platform that more accurately assesses the fidelity of cellular engineering than existing methodologies and generates hypotheses for improving cell derivations. Analyzing expression data from 56 published reports, we found that cells derived via directed differentiation more closely resemble their in vivo counterparts than products of direct conversion, as reflected by the establishment of target cell-type gene regulatory networks (GRNs). Furthermore, we discovered that directly converted cells fail to adequately silence expression programs of the starting population, and that the establishment of unintended GRNs is common to virtually every cellular engineering paradigm. CellNet provides a platform for quantifying how closely engineered cell populations resemble their target cell type and a rational strategy to guide enhanced cellular engineering. PMID:25126793
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CellNet: network biology applied to stem cell engineering.
Cahan, Patrick; Li, Hu; Morris, Samantha A; Lummertz da Rocha, Edroaldo; Daley, George Q; Collins, James J
2014-08-14
Somatic cell reprogramming, directed differentiation of pluripotent stem cells, and direct conversions between differentiated cell lineages represent powerful approaches to engineer cells for research and regenerative medicine. We have developed CellNet, a network biology platform that more accurately assesses the fidelity of cellular engineering than existing methodologies and generates hypotheses for improving cell derivations. Analyzing expression data from 56 published reports, we found that cells derived via directed differentiation more closely resemble their in vivo counterparts than products of direct conversion, as reflected by the establishment of target cell-type gene regulatory networks (GRNs). Furthermore, we discovered that directly converted cells fail to adequately silence expression programs of the starting population and that the establishment of unintended GRNs is common to virtually every cellular engineering paradigm. CellNet provides a platform for quantifying how closely engineered cell populations resemble their target cell type and a rational strategy to guide enhanced cellular engineering. Copyright © 2014 Elsevier Inc. All rights reserved.
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Educational MOO: Text-Based Virtual Reality for Learning in Community. ERIC Digest.
Turbee, Lonnie
MOO stands for "Multi-user domain, Object-Oriented." Early multi-user domains, or "MUDs," began as net-based dungeons-and-dragons type games, but MOOs have evolved from these origins to become some of cyberspace's most fascinating and engaging online communities. MOOs are social environments in a text-based virtual reality…
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Mixed Methods for Mixed Reality: Understanding Users' Avatar Activities in Virtual Worlds
Feldon, David F.; Kafai, Yasmin B.
2008-01-01
This paper examines the use of mixed methods for analyzing users' avatar-related activities in a virtual world. Server logs recorded keystroke-level activity for 595 participants over a six-month period in Whyville.net, an informal science website. Participants also completed surveys and participated in interviews regarding their experiences.…
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Progress in design and analysis of the net water cooled liquid breeder blanket
International Nuclear Information System (INIS)
Danner, W.; Rieger, M.; Verschuur, K.A.; Vieider, G.; Casini, G.; Chazalon, M.; Libin, B.; Farfaletti-Casali, F.; Piana, R.
1987-01-01
The NET liquid breeder blanket was subjected to a major design revision and integrated in the new NET-DN machine configuration. In this paper briefly the most essential design features are summarized and some results from thermohydraulics and 1D as well as 3D neutronics analyses are presented. It is concluded that the performance meets well the requirements of NET but that the concept needs substantial improvement if applied to a reactor
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Net alkalinity and net acidity 2: Practical considerations
Kirby, C.S.; Cravotta, C.A.
2005-01-01
The pH, alkalinity, and acidity of mine drainage and associated waters can be misinterpreted because of the chemical instability of samples and possible misunderstandings of standard analytical method results. Synthetic and field samples of mine drainage having various initial pH values and concentrations of dissolved metals and alkalinity were titrated by several methods, and the results were compared to alkalinity and acidity calculated based on dissolved solutes. The pH, alkalinity, and acidity were compared between fresh, unoxidized and aged, oxidized samples. Data for Pennsylvania coal mine drainage indicates that the pH of fresh samples was predominantly acidic (pH 2.5-4) or near neutral (pH 6-7); ??? 25% of the samples had pH values between 5 and 6. Following oxidation, no samples had pH values between 5 and 6. The Standard Method Alkalinity titration is constrained to yield values >0. Most calculated and measured alkalinities for samples with positive alkalinities were in close agreement. However, for low-pH samples, the calculated alkalinity can be negative due to negative contributions by dissolved metals that may oxidize and hydrolyze. The Standard Method hot peroxide treatment titration for acidity determination (Hot Acidity) accurately indicates the potential for pH to decrease to acidic values after complete degassing of CO2 and oxidation of Fe and Mn, and it indicates either the excess alkalinity or that required for neutralization of the sample. The Hot Acidity directly measures net acidity (= -net alkalinity). Samples that had near-neutral pH after oxidation had negative Hot Acidity; samples that had pH mine drainage treatment can lead to systems with insufficient Alkalinity to neutralize metal and H+ acidity and is not recommended. The use of net alkalinity = -Hot Acidity titration is recommended for the planning of mine drainage treatment. The use of net alkalinity = (Alkalinitymeasured - Aciditycalculated) is recommended with some cautions
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WE-NET: Japanese hydrogen program
International Nuclear Information System (INIS)
Mitsugi, Chiba; Harumi, Arai; Kenzo, Fukuda
1998-01-01
The Agency of Industrial Science and Technology (AIST), in the Ministry of International Trade and Industry (MITI), started the New Sunshine Program in 1993 by unifying the Sunshine Program (R and D on new energy technology), the Moonlight Program (R and D on energy conservation technology), and the Research and Development Program for Environmental Technology. The objective of the new program is to develop innovative technologies to allow sustainable growth while solving energy and environmental issues. One of the new projects in this program is the ''International Clean Energy System Technology Utilizing Hydrogen (World Energy Network)'': WE-NET. The goal of WE-NET is to construct a worldwide energy network for effective supply, transportation and utilization of renewable energy using hydrogen. The WE-NET program extends over 28 years from 1993 to 2020. In Phase 1, we started core research in areas such as development of high efficiency technologies including hydrogen production using polymer electrolyte membrane water electrolysis, hydrogen combustion turbines, etc. (author)
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Virtual Mission First Results Supporting the WATER HM Satellite Concept
Alsdorf, D.; Andreadis, K.; Lettenmaier, D.; Moller, D.; Rodriguez, E.; Bates, P.; Mognard, N.; Participants, W.
2007-12-01
Surface fresh water is essential for life, yet we have surprisingly poor knowledge of its variability in space and time. Similarly, ocean circulation and ocean-atmosphere interactions fundamentally drive weather and climate variability, yet the global ocean current and eddy field (e.g., the Gulf Stream) that affects ocean circulation is poorly known. The Water And Terrestrial Elevation Recovery Hydrosphere Mapper satellite mission concept (WATER HM or SWOT per the NRC Decadal Survey) is a swath-based interferometric-altimeter designed to acquire elevations of ocean and terrestrial water surfaces at unprecedented spatial and temporal resolutions. WATER HM will have tremendous implications for estimation of the global water cycle, water management, ocean and coastal circulation, and assessment of many water-related impacts from climate change (e.g., sea level rise, carbon evasion, etc.). We describe a hydrological "virtual mission" (VM) for WATER HM which consists of: (a) A hydrodynamic-instrument simulation model that maps variations in water levels along river channels and across floodplains. These are then assimilated to estimate discharge and to determine trade-offs between resolutions and mission costs. (b) Measurements from satellites to determine feasibility of existing platforms for measuring storage changes and estimating discharge. First results demonstrate that: (1) Ensemble Kalman filtering of VM simulations recover water depth and discharge, reducing the discharge RMSE from 23.2% to 10.0% over an 84- day simulation period, relative to a simulation without assimilation. The filter also shows that an 8-day overpass frequency produces discharge relative errors of 10.0%, while 16-day and 32-day frequencies result in errors of 12.1% and 16.9%, respectively. (2) SRTM measurements of water surfaces along the Mississippi, Missouri, Ohio, and Amazon rivers, as well as smaller tributaries, show height standard deviations of 5 meters or greater (SRTM is the
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Directory of Open Access Journals (Sweden)
André Schardong
2009-01-01
Full Text Available Este artigo apresenta uma ferramenta para análise de sistemas complexos de recursos hídricos denominada AcquaNetXL, que foi desenvolvida no formato de planilha eletrônica, na qual foram incorporados dois modelos de otimização, um linear e outro não linear. Essa ferramenta mantém os conceitos e os atributos de um sistema de suporte a decisão, ou seja, possui as características de estreitar a comunicação entre o usuário e o computador, de facilitar o entendimento, a formulação do problema, a interpretação dos resultados de análise e auxiliar no processo de tomada de decisão, tornando-o mais ordenado, objetivo e transparente. O desempenho do algoritmo utilizado na solução dos problemas de alocação de água foi satisfatório, especialmente para o modelo linear.This article presents a tool for the allocation analysis of complex systems of water resources, called AcquaNetXL, developed in the form of spreadsheet in which a model of linear optimization and another nonlinear were incorporated. The AcquaNetXL keeps the concepts and attributes of a decision support system. In other words, it straightens out the communication between the user and the computer, facilitates the understanding and the formulation of the problem, the interpretation of the results and it also gives a support in the process of decision making, turning it into a clear and organized process. The performance of the algorithms used for solving the problems of water allocation was satisfactory especially for the linear model.
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Multi-agent: a technique to implement geo-visualization of networked virtual reality
Lin, Zhiyong; Li, Wenjing; Meng, Lingkui
2007-06-01
Networked Virtual Reality (NVR) is a system based on net connected and spatial information shared, whose demands cannot be fully meet by the existing architectures and application patterns of VR to some extent. In this paper, we propose a new architecture of NVR based on Multi-Agent framework. which includes the detailed definition of various agents and their functions and full description of the collaboration mechanism, Through the prototype system test with DEM Data and 3D Models Data, the advantages of Multi-Agent based Networked Virtual Reality System in terms of the data loading time, user response time and scene construction time etc. are verified. First, we introduce the characters of Networked Virtual Realty and the characters of Multi-Agent technique in Section 1. Then we give the architecture design of Networked Virtual Realty based on Multi-Agent in Section 2.The Section 2 content includes the rule of task division, the multi-agent architecture design to implement Networked Virtual Realty and the function of agents. Section 3 shows the prototype implementation according to the design. Finally, Section 4 discusses the benefits of using Multi-Agent to implement geovisualization of Networked Virtual Realty.
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Comparing virtual with physical wedge for the transmission factors
International Nuclear Information System (INIS)
Lin Kuei-Hua; Lin Jao-Perng; Chu Tieh-Chi; Liu Mu-Tai
2000-01-01
This paper investigates the discrepancies between virtual wedge and physical wedge at the standard wedge angles of 15, 30, 45, and 60 degrees. The dose distributions for virtual wedge and physics wedge were measured by using a commercial multichamber detector array. The transmission factors of each virtual wedge and physical wedge were measured for Siemens PRIMUS 3008 linear accelerator by single ion chamber. These factors were used to set-up the clinical treatment data tables for clinical dosimetry for virtual wedge utilization. The Wellhoefer IC15, 0.13cc chamber was installed on the chamber frame of Wellhoefer water phantom (48x48x40 cm 3 ). The surface of water was at 100 cm SSD. The output factor in water were measured on the central axis of each field at 5 cm depth for 6MV or 10 cm depth for 15MV X-ray on virtual wedge and physical wedge. Comparing virtual wedge with physical wedge for transmission factor as field size range from 4x4 to 25x25 cm 2 . We have measured the dose distributions using the chamber array for 25x25 cm 2 virtual wedge fields and physical wedge fields at wedge angles of 15deg to 60deg. The dose profiles at various depths were also measured using the chamber array. The transmission factors of each physical wedge were slowly increased as field sizes increase, and had different value for each wedge angle. The transmission factors of each virtual wedge were almost constant value as 1.0 for each wedge angle. The results show that the dose profiles including the penumbra dose measured by the chamber array for virtual wedge agree with those measured for the physical wedge. For transmission factors of virtual wedge were constant value as 1.0 for each angles, namely output without wedge is almost equal to output with wedge on the central axis. Virtual wedge has practical and dosimetric advantages over physical wedge. (author)
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Directory of Open Access Journals (Sweden)
Vera Menezes de O Paiva
2010-12-01
Full Text Available Este texto apresenta algumas visões epistemológicas - objetivismo, subjetivismo e experiencialismo -, em uma tentativa de compreender os conceitos de conhecimento e de aprendizagem subjacentes à construção de ambientes virtuais de aprendizagem. Apresenta, também, uma descrição de três plataformas de aprendizagem gratuitas - AulaNet, Moodle e TeleEduc - e enfatiza que outras ferramentas do internet pode ser adicionadas a esses ambientes educacionais virtuais, de forma a propiciar mais experiências de aprendizagem. Finalmente, conclui que o ambiente virtual retira os professores do palco da aprendizagem, pois eles também podem aprender com os alunos.This text presents some epistemological views - objectivism, subjectivism and experientialism - aiming at understanding the concepts of knowledge and learning which underlay the construction of virtual learning environments. It also presents a description of three free learning software - AulaNet, Moodle and TeleEduc - and emphasizes that other internet tools can be added to those virtual educational environments in order to offer more learning experiences. Finally, it concludes that learning environments remove teachers from the learning stage as they can also learn with the students.
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Drag of Clean and Fouled Net Panels--Measurements and Parameterization of Fouling.
Directory of Open Access Journals (Sweden)
Lars Christian Gansel
Full Text Available Biofouling is a serious problem in marine aquaculture and it has a number of negative impacts including increased forces on aquaculture structures and reduced water exchange across nets. This in turn affects the behavior of fish cages in waves and currents and has an impact on the water volume and quality inside net pens. Even though these negative effects are acknowledged by the research community and governmental institutions, there is limited knowledge about fouling related effects on the flow past nets, and more detailed investigations distinguishing between different fouling types have been called for. This study evaluates the effect of hydroids, an important fouling organism in Norwegian aquaculture, on the forces acting on net panels. Drag forces on clean and fouled nets were measured in a flume tank, and net solidity including effect of fouling were determined using image analysis. The relationship between net solidity and drag was assessed, and it was found that a solidity increase due to hydroids caused less additional drag than a similar increase caused by change in clean net parameters. For solidities tested in this study, the difference in drag force increase could be as high as 43% between fouled and clean nets with same solidity. The relationship between solidity and drag force is well described by exponential functions for clean as well as for fouled nets. A method is proposed to parameterize the effect of fouling in terms of an increase in net solidity. This allows existing numerical methods developed for clean nets to be used to model the effects of biofouling on nets. Measurements with other types of fouling can be added to build a database on effects of the accumulation of different fouling organisms on aquaculture nets.
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Virtual water content of temperate cereals and maize: Present and potential future patterns
Fader, Marianela; Rost, Stefanie; Müller, Christoph; Bondeau, Alberte; Gerten, Dieter
2010-04-01
SummaryKnowledge of the virtual water content (VWC) of crops and especially its possible future developments is helpful for improvements in water productivity and water management, which are necessary at global scale due to rising demand for food, the necessity to ease present and future water scarcity, and the reduction of poverty. Using a dynamic global vegetation and water balance model (LPJmL), this study quantifies the VWC of two of the most important crop types worldwide, temperate cereals and maize, at high spatial resolution (0.5°). We analyzed present conditions (1999-2003) and also for the first time also for scenarios of future climate and increasing atmospheric CO 2 concentrations (2041-2070; HadCM3, ECHAM5 and CCSM3 climate models, A2 emissions scenario). VWC presently differs significantly among regions: highest values are common in large parts of Africa (>2 m 3 kg -1), and lowest values were found e.g. for Central Europe (Europe, South Africa, Argentina, Australia and South East Asia—are projected to become less water efficient (higher VWC) for at least one of the crop types. CO 2 fertilisation was simulated to generally reduce VWC, though realisation of this effect in the field will depend, for example, on the intensity of nutrient management in the future. The potentially adverse future changes in VWC found here pose a challenge to water management efforts and eventually global trade policies.
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Higher-moment measurements of net-kaon, net-charge and net-proton multiplicity distributions at STAR
International Nuclear Information System (INIS)
Sarkar, Amal
2014-01-01
In this paper, we report the measurements of the various moments, such as mean, standard deviation (σ), skewness (S) and kurtosis (κ) of the net-kaon, net-charge and net-proton multiplicity distributions at mid-rapidity in Au + Au collisions from √(s NN )=7.7 to 200 GeV with the STAR experiment at RHIC. This work has been done with the aim to locate the critical point on the QCD phase diagram. These moments and their products are related to the thermodynamic susceptibilities of conserved quantities such as net baryon number, net charge, and net strangeness as well as to the correlation length of the system which diverges in an ideal infinite thermodynamic system at the critical point. For a finite system, existing for a finite time, a non-monotonic behavior of these variables would indicate the presence of the critical point. Furthermore, we also present the moment products Sσ, κσ 2 of net-kaon, net-charge and net-proton multiplicity distributions as a function of collision centrality and energy. The energy and the centrality dependence of higher moments and their products have been compared with different models
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Virtual VMASC: A 3D Game Environment
Manepalli, Suchitra; Shen, Yuzhong; Garcia, Hector M.; Lawsure, Kaleen
2010-01-01
The advantages of creating interactive 3D simulations that allow viewing, exploring, and interacting with land improvements, such as buildings, in digital form are manifold and range from allowing individuals from anywhere in the world to explore those virtual land improvements online, to training military personnel in dealing with war-time environments, and to making those land improvements available in virtual worlds such as Second Life. While we haven't fully explored the true potential of such simulations, we have identified a requirement within our organization to use simulations like those to replace our front-desk personnel and allow visitors to query, naVigate, and communicate virtually with various entities within the building. We implemented the Virtual VMASC 3D simulation of the Virginia Modeling Analysis and Simulation Center (VMASC) office building to not only meet our front-desk requirement but also to evaluate the effort required in designing such a simulation and, thereby, leverage the experience we gained in future projects of this kind. This paper describes the goals we set for our implementation, the software approach taken, the modeling contribution made, and the technologies used such as XNA Game Studio, .NET framework, Autodesk software packages, and, finally, the applicability of our implementation on a variety of architectures including Xbox 360 and PC. This paper also summarizes the result of our evaluation and the lessons learned from our effort.
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TiArA: a virtual appliance for the analysis of Tiling Array data.
Directory of Open Access Journals (Sweden)
Jason A Greenbaum
2010-04-01
Full Text Available Genomic tiling arrays have been described in the scientific literature since 2003, yet there is a shortage of user-friendly applications available for their analysis.Tiling Array Analyzer (TiArA is a software program that provides a user-friendly graphical interface for the background subtraction, normalization, and summarization of data acquired through the Affymetrix tiling array platform. The background signal is empirically measured using a group of nonspecific probes with varying levels of GC content and normalization is performed to enforce a common dynamic range.TiArA is implemented as a standalone program for Linux systems and is available as a cross-platform virtual machine that will run under most modern operating systems using virtualization software such as Sun VirtualBox or VMware. The software is available as a Debian package or a virtual appliance at http://purl.org/NET/tiara.
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Virtual Team Communication and Collaboration in Army and Corporate Applications
2009-06-12
including e-mail, instant messaging, net meetings, audio conferences, and a virtual team work space (Lipnack and Stamps 2007, 1). This case study...Figure 15. Digital Avatar Filing System Example Source: Joe Fernandez, IBM Uses 3D Imaging to Visualise Patient Records...Use of multiple modes of media to transmit data. Examples include audio , video videoconference, and e-mail Structured Problem or Task Clearly
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Directory of Open Access Journals (Sweden)
André Luiz Scarano Camargo
2012-06-01
Full Text Available In order to understand the influence of a net cage tilapia culture on the environment, water quality parameters were investigated during the period between December, 2005 and November, 2007. Three sampling stations were established in the reservoir of Nova Avanhandava (Zacarias, São Paulo State as follows: upstream of net cage area (P1, in the rearing place (P2 and downstream of net cage area (P3. The mean values of the parameters examined in the water sampling stations were within the standards of water quality recommended by resolution no. 357/2005 of the Conselho Nacional do Meio Ambiente for class 2 freshwater bodies. A significantly higher mean concentration of total phosphorus (p -1 was the result of the uneaten feed and feces of fish. The average concentration of total phosphorus in P3 was lower (0.015 mg L-1, which was assimilated by the aquatic ecosystem. The frequent monitoring of the water parameters is fundamental, so the producer can adjust the management according to environmental conditions, by reducing fish density or changing feeding rates for example, to mitigate or avoid water quality deterioration.
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Directory of Open Access Journals (Sweden)
José Antonio Jerónimo Montes
2010-12-01
Full Text Available Se presentan los resultados de un análisis de los procesos de formación, considerando las posibilidades de los entornos virtuales para facilitar u obstaculizar la colaboración en Red, y por ende la construcción de comunidades de práctica, con la finalidad de avanzar hacia la construcción de comunidades de aprendizaje, basadas en la colaboración a distancia haciendo uso de un entorno de teleformación. lo anterior para de evaluar de que forma esos sistemas de gestión de los aprendizajes en Red (LMS incorporan elementos de diseño virtual para la metodología que se desea incorporar en los procesos de evaluación cualitativa y cuantitativa, específicamente los espacios virtuales para el trabajo colaborativo y las herramientas de comunicación como son los foros virtuales.The results of an analysis of the processes of formation in the educative modality through Internet a distance, considering the possibilities of the virtual environment to facilitate or to prevent the collaboration in network, and therefore the construction of practice communities; the previous thing with the intention to evaluate of that forms those systems of management of the learning in Net (LMS incorporates elements of virtual design for the methodology that is desired to incorporate in the processes of qualitative and quantitative evaluation, specifically the virtual spaces for the collaborative work and the tools of communication as they are the virtual forums.
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Astronomical Virtual Observatories Through International Collaboration
Directory of Open Access Journals (Sweden)
Masatoshi Ohishi
2010-03-01
Full Text Available Astronomical Virtual Observatories (VOs are emerging research environment for astronomy, and 16 countries and a region have funded to develop their VOs based on international standard protocols for interoperability. The 16 funded VO projects have established the International Virtual Observatory Alliance (http://www.ivoa.net/ to develop the standard interoperable interfaces such as registry (meta data, data access, query languages, output format (VOTable, data model, application interface, and so on. The IVOA members have constructed each VO environment through the IVOA interfaces. National Astronomical Observatory of Japan (NAOJ started its VO project (Japanese Virtual Observatory - JVO in 2002, and developed its VO system. We have succeeded to interoperate the latest JVO system with other VOs in the USA and Europe since December 2004. Observed data by the Subaru telescope, satellite data taken by the JAXA/ISAS, etc. are connected to the JVO system. Successful interoperation of the JVO system with other VOs means that astronomers in the world will be able to utilize top-level data obtained by these telescopes from anywhere in the world at anytime. System design of the JVO system, experiences during our development including problems of current standard protocols defined in the IVOA, and proposals to resolve these problems in the near future are described.
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Simulation of machine-maintenance training in virtual environment
International Nuclear Information System (INIS)
Yoshikawa, Hidekazu; Tezuka, Tetsuo; Kashiwa, Ken-ichiro; Ishii, Hirotake
1997-01-01
The periodical inspection of nuclear power plants needs a lot of workforces with a high degree of technical skill for the maintenance of various sorts of machines. Therefore, a new type of maintenance training system is required, where trainees can get training safely, easily and effectively. In this study we developed a training simulation system for disassembling a check valve in virtual environment (VE). The features of this system are as follows: Firstly, the trainees can execute tasks even in wrong order, and can experience the resultant conditions. In order to realize this environment, we developed a new Petri-net model for representing the objects' states in VE. This Petri-net model has several original characteristics, which make it easier to manage the change of the objects' states. Furthermore, we made a support system for constructing the Petri-net model of machine-disassembling training, because the Petri-net model is apt to become of large size. The effectiveness of this support system is shown through the system development. Secondly, this system can perform appropriate tasks to be done next in VE whenever the trainee wants even after some mistakes have been made. The effectiveness of this function has also been confirmed by experiments. (author)
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Directory of Open Access Journals (Sweden)
Raul Munoz Castillo
2017-11-01
Full Text Available Brazil plays a major role in the global biofuel economy as the world’s second largest producer and consumer and the largest exporter of ethanol. Its demand is expected to significantly increase in coming years, largely driven by national and international carbon mitigation targets. However, biofuel crops require significant amounts of water and land resources that could otherwise be used for the production of food, urban water supply, or energy generation. Given Brazil’s uneven spatial distribution of water resources among regions, a potential expansion of ethanol production will need to take into account regional or local water availability, as an increased water demand for irrigation would put further pressure on already water-scarce regions and compete with other users. By applying an environmentally extended multiregional input-output (MRIO approach, we uncover the scarce water footprint and the interregional virtual water flows associated with sugarcane-derived biofuel production driven by domestic final consumption and international exports in 27 states in Brazil. Our results show that bio-ethanol is responsible for about one third of the total sugarcane water footprint besides sugar and other processed food production. We found that richer states such as São Paulo benefit by accruing a higher share of economic value added from exporting ethanol as part of global value chains while increasing water stress in poorer states through interregional trade. We also found that, in comparison with other crops, sugarcane has a comparative advantage when rainfed while showing a comparative disadvantage as an irrigated crop; a tradeoff to be considered when planning irrigation infrastructure and bioethanol production expansion.
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Liao, Chenzhong; Liu, Bing; Shi, Leming; Zhou, Jiaju; Lu, Xian-Ping
2005-07-01
Based on the structural characters of PPAR modulators, a virtual combinatorial library containing 1226,625 compounds was constructed using SMILES strings. Selected ADME filters were employed to compel compounds having poor drug-like properties from this library. This library was converted to sdf and mol2 files by CONCORD 4.0, and was then docked to PPARgamma by DOCK 4.0 to identify new chemical entities that may be potential drug leads against type 2 diabetes and other metabolic diseases. The method to construct virtual combinatorial library using SMILES strings was further visualized by Visual Basic.net that can facilitate the needs of generating other type virtual combinatorial libraries.
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Utilization of virtual prototyping in development of CMM
International Nuclear Information System (INIS)
Raneda, A.; Pessi, P.; Siuko, M.; Handroos, H.; Palmer, J.; Vilenius, M.
2003-01-01
The characteristic advantages of hydraulics (high power density, simple construction and reliability) together with the characteristics of water as the pressure medium (fire and environmentally safe, chemically neutral, not activated nor affected by radiation) are highlighted in critical applications such as remote handling operations in International Thermonuclear Experimental Reactor (ITER). However, component cost and lack of wide selection of water hydraulic components make it difficult to build and to test complex water hydraulic systems. The use of virtual prototyping for the development of water hydraulic tools can be used to address this problem. Rapidly increased computational power has created conditions for extensive numerical calculations, enabling computer aided virtual prototyping to replace physical prototype phases in product development
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Data Driven Estimation of Transpiration from Net Water Fluxes: the TEA Algorithm
Nelson, J. A.; Carvalhais, N.; Cuntz, M.; Delpierre, N.; Knauer, J.; Migliavacca, M.; Ogee, J.; Reichstein, M.; Jung, M.
2017-12-01
The eddy covariance method, while powerful, can only provide a net accounting of ecosystem fluxes. Particularly with water cycle components, efforts to partitioning total evapotranspiration (ET) into the biotic component (transpiration, T) and the abiotic component (here evaporation, E) have seen limited success, with no one method emerging as a standard.Here we demonstrate a novel method that uses ecosystem WUE to predict transpiration in two steps: (1) a filtration step that to isolate the signal of ET for periods where E is minimized and ET is likely dominated by the signal of T; and (2) a step which predicts the WUE using meteorological variables, as well as information derived from the carbon and energy fluxes. To assess the the underlying assumptions, we tested the proposed method on three ecological models, allowing validation where the underlying carbon:water relationships, as well as the transpiration estimates, are know.The partitioning method shows high correlation (R²>0.8) between Tmodel/ET and TTEA/ET across timescales from half-hourly to annually, as well as capturing spatial variability across sites. Apart from predictive performance, we explore the sensitivities of the method to the underlying assumptions, such as the effects of residual evaporation in the training dataset. Furthermore, we show initial transpiration estimates from the algorithm at global scale, via the FLUXNET dataset.
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Directory of Open Access Journals (Sweden)
Muhammad Junaidi
2015-02-01
Full Text Available ABSTRACT The development of lobster farming in floating net cage in Ekas Bay caused an environmental degradation such as decrease water quality due to some aquaculture wastes. The purposes of this study were to determine the status of water quality and their effect on growth and survival rate of lobster reared in floating net cages (FNC in the Ekas Bay, West Nusa Tenggara Province. Water sample collection and handling referred to the APHA (1992. Analyses of water quality data were conducted using Principal Component Analysis. Determination of the water quality status of Ekas Bay was performed with STORET system. Multivariate analyses were used to determine the relationship between water quality, growth, and survival rate of lobster reared in FNC. Results showed that Ekas Bay water quality status was categorized in class C (medium contaminated, which exceeded some quality standard parameters such as ammonia (0.3 mg/l, nitrate (0.008 mg/l, and phosphate (0.015 mg/l. During lobster farming activities feeding with trash fish for 270 days, we obtained daily growth rate of 0.74% (lower than normal growth rate of 0.86%, survival rate of 66% (lower than normal survival rate of 86.7%, and feed conversion ratio of 11.15. Ammonia was found as a dominant factor reducing growth and survival rate of lobster reared in FNC. Keywords: water quality, lobsters, growth, survival, Ekas Bay
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Virtually teaching virtual leadership
DEFF Research Database (Denmark)
Henriksen, Thomas Duus; Nielsen, Rikke Kristine; Børgesen, Kenneth
2017-01-01
This paper seeks to investigate the challenges to virtual collaboration and leadership on basis of findings from a virtual course on collaboration and leadership. The course used for this experiment was designed as a practical approach, which allowed participants to experience curriculum phenomena....... This experimental course provided insights into the challenges involved in virtual processes, and those experiences where used for addressing the challenges that virtual leadership is confronted with. Emphasis was placed on the reduction of undesired virtual distance and its consequences through affinity building....... We found that student scepticism appeared when a breakdown resulted in increasing virtual distance, and raises questions on how leaders might translate or upgrade their understandings of leadership to handling such increased distance through affinity building....
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Virtual water content for meat and egg production through livestock farming in Saudi Arabia
Chowdhury, Shakhawat; Ouda, Omar K. M.; Papadopoulou, Maria P.
2017-12-01
The concept of virtual water content (VWC) may facilitate an understanding of total water demand for commodity production. The water consumption for livestock production forms a significant fraction of freshwater demand in arid regions, i.e., Saudi Arabia. In this paper, VWC was estimated for different livestocks in the 13 regions of Saudi Arabia. The VWC for camel production was also estimated, which has not been investigated in the previous studies. The overall VWC for livestock in Saudi Arabia was about 10.5 and 8.9 billion m3 in 2006 and 2010, respectively. This study shows the decreasing trend of overall VWC in producing livestock in Saudi Arabia. The VWC were highest in Riyadh followed by Eastern region, Qaseem, Hail, and Makkah with ranges of 3587-4112, 1684-2044, 1007-1331, 644-810, and 504-715 million m3/year, respectively. The results demonstrate that a shift in diet from the high VWC meat to low VWC meat may reduce the overall VWC for livestock production. The findings of this analysis provide an assessment of the quantity and trend of water demand for livestock production in Saudi Arabia, which is useful to assess the development of an information-based agricultural water management strategy.
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Optimum Temperatures for Net Primary Productivity of Three Tropical Seagrass Species
Directory of Open Access Journals (Sweden)
Catherine J. Collier
2017-08-01
Full Text Available Rising sea water temperature will play a significant role in responses of the world's seagrass meadows to climate change. In this study, we investigated seasonal and latitudinal variation (spanning more than 1,500 km in seagrass productivity, and the optimum temperatures at which maximum photosynthesis and net productivity (for the leaf and the whole plant occurs, for three seagrass species (Cymodocea serrulata, Halodule uninervis, and Zostera muelleri. To obtain whole plant net production, photosynthesis, and respiration rates of leaves and the root/rhizome complex were measured using oxygen-sensitive optodes in closed incubation chambers at temperatures ranging from 15 to 43°C. The temperature-dependence of photosynthesis and respiration was fitted to empirical models to obtain maximum metabolic rates and thermal optima. The thermal optimum (Topt for gross photosynthesis of Z. muelleri, which is more commonly distributed in sub-tropical to temperate regions, was 31°C. The Topt for photosynthesis of the tropical species, H. uninervis and C. serrulata, was considerably higher (35°C on average. This suggests that seagrass species are adapted to water temperature within their distributional range; however, when comparing among latitudes and seasons, thermal optima within a species showed limited acclimation to ambient water temperature (Topt varied by 1°C in C. serrulata and 2°C in H. uninervis, and the variation did not follow changes in ambient water temperature. The Topt for gross photosynthesis were higher than Topt calculated from plant net productivity, which includes above- and below-ground respiration for Z. muelleri (24°C and H. uninervis (33°C, but remained unchanged at 35°C in C. serrulata. Both estimated plant net productivity and Topt are sensitive to the proportion of below-ground biomass, highlighting the need for consideration of below- to above-ground biomass ratios when applying thermal optima to other meadows. The
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Virtual experiments: a new approach for improving process conceptualization in hillslope hydrology
Weiler, Markus; McDonnell, Jeff
2004-01-01
We present an approach for process conceptualization in hillslope hydrology. We develop and implement a series of virtual experiments, whereby the interaction between water flow pathways, source and mixing at the hillslope scale is examined within a virtual experiment framework. We define these virtual experiments as 'numerical experiments with a model driven by collective field intelligence'. The virtual experiments explore the first-order controls in hillslope hydrology, where the experimentalist and modeler work together to cooperatively develop and analyze the results. Our hillslope model for the virtual experiments (HillVi) in this paper is based on conceptualizing the water balance within the saturated and unsaturated zone in relation to soil physical properties in a spatially explicit manner at the hillslope scale. We argue that a virtual experiment model needs to be able to capture all major controls on subsurface flow processes that the experimentalist might deem important, while at the same time being simple with few 'tunable parameters'. This combination makes the approach, and the dialog between experimentalist and modeler, a useful hypothesis testing tool. HillVi simulates mass flux for different initial conditions under the same flow conditions. We analyze our results in terms of an artificial line source and isotopic hydrograph separation of water and subsurface flow. Our results for this first set of virtual experiments showed how drainable porosity and soil depth variability exert a first order control on flow and transport at the hillslope scale. We found that high drainable porosity soils resulted in a restricted water table rise, resulting in more pronounced channeling of lateral subsurface flow along the soil-bedrock interface. This in turn resulted in a more anastomosing network of tracer movement across the slope. The virtual isotope hydrograph separation showed higher proportions of event water with increasing drainable porosity. When
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International Nuclear Information System (INIS)
Nahrgang, Marlene; Schuster, Tim; Stock, Reinhard; Mitrovski, Michael; Bleicher, Marcus
2012-01-01
We explore the potential of net-baryon, net-proton and net-charge kurtosis measurements to investigate the properties of hot and dense matter created in relativistic heavy-ion collisions. Contrary to calculations in a grand-canonical ensemble we explicitly take into account exact electric and baryon charge conservation on an event-by-event basis. This drastically limits the width of baryon fluctuations. A simple model to account for this is to assume a grand-canonical distribution with a sharp cut-off at the tails. We present baseline predictions of the energy dependence of the net-baryon, net-proton and net-charge kurtosis for central (b≤2.75 fm) Pb+Pb/Au+Au collisions from E lab =2A GeV to √(s NN )=200 GeV from the UrQMD model. While the net-charge kurtosis is compatible with values around zero, the net-baryon number decreases to large negative values with decreasing beam energy. The net-proton kurtosis becomes only slightly negative for low √(s NN ). (orig.)
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Pajusalu, Liina; Martin, Georg; Põllumäe, Arno; Paalme, Tiina
2016-01-01
Seagrasses are distributed across the globe and their communities may play key roles in the coastal ecosystems. Seagrass meadows are expected to benefit from the increased carbon availability which might be used in photosynthesis in a future high CO2 world. The main aim of this study was to examine the effect of elevated pCO2 on the net photosynthesis of seagrass Zostera marina in a brackish water environment. The short-term mesocosm experiments were conducted in Kõiguste Bay (northern part o...
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Comparison of the performance of net radiation calculation models
DEFF Research Database (Denmark)
Kjærsgaard, Jeppe Hvelplund; Cuenca, R.H.; Martinez-Cob, A.
2009-01-01
. The long-wave radiation models included a physically based model, an empirical model from the literature, and a new empirical model. Both empirical models used only solar radiation as required for meteorological input. The long-wave radiation models were used with model calibration coefficients from......Daily values of net radiation are used in many applications of crop-growth modeling and agricultural water management. Measurements of net radiation are not part of the routine measurement program at many weather stations and are commonly estimated based on other meteorological parameters. Daily...... values of net radiation were calculated using three net outgoing long-wave radiation models and compared to measured values. Four meteorological datasets representing two climate regimes, a sub-humid, high-latitude environment and a semi-arid mid-latitude environment, were used to test the models...
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Nitrogen transformations in wetlands: Effects of water flow patterns
Energy Technology Data Exchange (ETDEWEB)
Davidsson, T.
1997-11-01
In this thesis, I have studied nitrogen turnover processes in water meadows. A water meadow is a wetland where water infiltrates through the soil of a grassland field. It is hypothesized that infiltration of water through the soil matrix promotes nutrient transformations compared to surface flow of water, by increasing the contact between water, nutrients, soil organic matter and bacteria. I have studied how the balance between nitrogen removal (denitrification, assimilative uptake, adsorption) and release (mineralization, desorption) processes are affected by water flow characteristics. Mass balance studies and direct denitrification measurements at two field sites showed that, although denitrification was high, net nitrogen removal in the water meadows was poor. This was due to release of ammonium and dissolved organic nitrogen (DON) from the soils. In laboratory studies, using {sup 15}N isotope techniques, I have shown that nitrogen turnover is considerably affected by hydrological conditions and by soil type. Infiltration increased virtually all the nitrogen processes, due to deeper penetration of nitrate and oxygen, and extended zones of turnover processes. On the contrary, soils and sediments with surface water flow, diffusion is the main transfer mechanism. The relation between release and removal processes sometimes resulted in shifts towards net nitrogen production. This occurred in infiltration treatments when ammonium efflux was high in relation to denitrification. It was concluded that ammonium and DON was of soil origin and hence not a product of dissimilatory nitrate reduction to ammonium. Both denitrification potential and mineralization rates were higher in peaty than in sandy soil. Vertical or horizontal subsurface flow is substantial in many wetland types, such as riparian zones, tidal salt marshes, fens, root-zone systems and water meadows. Moreover, any environment where aquatic and terrestrial ecosystems meet, and where water level fluctuates
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Yao, Z.; Du, Y.; Tao, Y.; Zheng, X.; Liu, C.; Lin, S.; Butterbach-Bahl, K.
2014-11-01
To safeguard food security and preserve precious water resources, the technology of water-saving ground cover rice production system (GCRPS) is being increasingly adopted for rice cultivation. However, changes in soil water status and temperature under GCRPS may affect soil biogeochemical processes that control the biosphere-atmosphere exchanges of methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2). The overall goal of this study is to better understand how net ecosystem greenhouse gas exchanges (NEGE) and grain yields are affected by GCRPS in an annual rice-based cropping system. Our evaluation was based on measurements of the CH4 and N2O fluxes and soil heterotrophic respiration (CO2 emissions) over a complete year, and the estimated soil carbon sequestration intensity for six different fertilizer treatments for conventional paddy and GCRPS. The fertilizer treatments included urea application and no N fertilization for both conventional paddy (CUN and CNN) and GCRPS (GUN and GNN), and solely chicken manure (GCM) and combined urea and chicken manure applications (GUM) for GCRPS. Averaging across all the fertilizer treatments, GCRPS increased annual N2O emission and grain yield by 40 and 9%, respectively, and decreased annual CH4 emission by 69%, while GCRPS did not affect soil CO2 emissions relative to the conventional paddy. The annual direct emission factors of N2O were 4.01, 0.09 and 0.50% for GUN, GCM and GUM, respectively, and 1.52% for the conventional paddy (CUN). The annual soil carbon sequestration intensity under GCRPS was estimated to be an average of -1.33 Mg C ha-1 yr-1, which is approximately 44% higher than the conventional paddy. The annual NEGE were 10.80-11.02 Mg CO2-eq ha-1 yr-1 for the conventional paddy and 3.05-9.37 Mg CO2-eq ha-1 yr-1 for the GCRPS, suggesting the potential feasibility of GCRPS in reducing net greenhouse effects from rice cultivation. Using organic fertilizers for GCRPS considerably reduced annual emissions of CH4
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Additive Manufacturing of Near-net Shaped Permanent Magnets
Energy Technology Data Exchange (ETDEWEB)
Paranthaman, M Parans [ORNL
2016-07-26
The technical objective of this technical collaboration phase I proposal is to fabricate near net-shaped permanent magnets using alloy powders utilizing direct metal deposition technologies at the ORNL MDF. Direct Manufacturing using the POM laser system was used to consolidate Nd2Fe14B (NdFeB) magnet powders into near net-shape parts efficiently and with virtually no wasted material as part of the feasibility study. We fabricated builds based on spherical NdFeB magnet particles. The results show that despite the ability to fabricate highly reactive materials in the laser deposition process, the magnetic coercivity and remanence of the NdFeB hard magnets is significantly reduced. X-ray powder diffraction in conjunction with electron microscopy showed that the material experienced a primary Nd2Fe17Bx solidification due to the undercooling effect (>60K). Consequently the presence of alpha iron phase resulted in deterioration of the build properties. Further optimization of the processing parameters is needed to maintain the Nd2Fe14B phase during fabrication.
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Beckmann, Jennifer; Weber, Peter
2015-01-01
The paper introduces a virtual collaborative learning setting called "Net Economy," which we established as part of an international learning network of currently seven universities. Using the Community of Inquiry framework as guidance and Canonical Action Research (CAR) as the chosen research design, the discussion forum of the online…
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Indian Academy of Sciences (India)
In a computer system, for example, typical discrete events ... This project brought out a series of influential reports on Petri net theory in the mid and late ... Technology became a leading centre for Petri net research and from then on, Petri nets ...
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Mekonnen, Mesfin; Hoekstra, Arjen Ysbert
2011-01-01
This study quantifies and maps the water footprints of nations from both a production and consumption perspective and estimates international virtual water flows and national and global water savings as a result of trade. The entire estimate includes a breakdown of water footprints, virtual water
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Water Sustainability Assessments for Four Net Zero Water Installations
2013-12-01
average daily water use, in six leaks. While the cost of the lost water might seem insignificant using current valuation methods, the financial impacts...One function of GFEBS is to identify facility maintenance requirements through integrated asset valuation and depreciation. The desired outcome is...considers tapping groundwater reservoirs as an additional water source. The most feasible groundwater source would likely originate in an alluvial valley
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Greco, F.
2008-12-01
This research considers the historical impact of virtual water into the geophysical arena by considering it as a human-led phenomenon that impacts the hydrologic system and, consequently, the environment as a whole. This paper is in line with the idea of including the humans into the water-balance model, and it is deepening the idea that this has to be done not only at the light of each watershed, but globally, looking at the role of water-trade embedded in food and tradable goods. Starting from a definition of what virtual water is, this research explores the role of crops export in the early U.S. Colonial time. As early as 1630 a huge biomass from here was already exported to the UK (the fur trade). In 1700 the tobacco export started, along with cereals exports and timber. An entire ecosystem has been "exported" in terms of water-embedded-in-goods. This was the beginning of a massive depletion of bio-mass stocks and flows, a raise in nitrogen discharge into the environment and its impact on the hydrological systems ( CUAHSI Summer Institute findings). Immigration and its effects on the water balance is also considered in this work. The experiment of interdisciplinary work of CUAHSI Summer Institute 2008 has proven that there is space for a historical reconstruction of evidence of human-led changes to the hydrological systems. This has been possible through the analysis of material stocks and flows, water-balance analysis of these stocks and flows, including human-led changes like international trade and population growth. This proposal will argue that these changes can also be identified by the term of 'socio- economic metabolism', in which societies are trading their goods internationally but taking the primary resources, including water, locally. This work will put the basis for the history of virtual water and its implications on both socio-economic metabolism and local geophysical changes.
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SIMULATION OF NET INFILTRATION FOR MODERN AND POTENTIAL FUTURE CLIMATES
Energy Technology Data Exchange (ETDEWEB)
J.A. Heveal
2000-06-16
This Analysis/Model Report (AMR) describes enhancements made to the infiltration model documented in Flint et al. (1996) and documents an analysis using the enhanced model to generate spatial and temporal distributions over a model domain encompassing the Yucca Mountain site, Nevada. Net infiltration is the component of infiltrated precipitation, snowmelt, or surface water run-on that has percolated below the zone of evapotranspiration as defined by the depth of the effective root zone, the average depth below the ground surface (at a given location) from which water is removed by evapotranspiration. The estimates of net infiltration are used for defining the upper boundary condition for the site-scale 3-dimensional Unsaturated-Zone Ground Water Flow and Transport (UZ flow and transport) Model (CRWMS M&O 2000a). The UZ flow and transport model is one of several process models abstracted by the Total System Performance Assessment model to evaluate expected performance of the potential repository at Yucca Mountain, Nevada, in terms of radionuclide transport (CRWMS M&O 1998). The net-infiltration model is important for assessing potential repository-system performance because output from this model provides the upper boundary condition for the UZ flow and transport model that is used to generate flow fields for evaluating potential radionuclide transport through the unsaturated zone. Estimates of net infiltration are provided as raster-based, 2-dimensional grids of spatially distributed, time-averaged rates for three different climate stages estimated as likely conditions for the next 10,000 years beyond the present. Each climate stage is represented using a lower bound, a mean, and an upper bound climate and corresponding net-infiltration scenario for representing uncertainty in the characterization of daily climate conditions for each climate stage, as well as potential climate variability within each climate stage. The set of nine raster grid maps provide spatially
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SIMULATION OF NET INFILTRATION FOR MODERN AND POTENTIAL FUTURE CLIMATES
International Nuclear Information System (INIS)
J.A. Heveal
2000-01-01
This Analysis/Model Report (AMR) describes enhancements made to the infiltration model documented in Flint et al. (1996) and documents an analysis using the enhanced model to generate spatial and temporal distributions over a model domain encompassing the Yucca Mountain site, Nevada. Net infiltration is the component of infiltrated precipitation, snowmelt, or surface water run-on that has percolated below the zone of evapotranspiration as defined by the depth of the effective root zone, the average depth below the ground surface (at a given location) from which water is removed by evapotranspiration. The estimates of net infiltration are used for defining the upper boundary condition for the site-scale 3-dimensional Unsaturated-Zone Ground Water Flow and Transport (UZ flow and transport) Model (CRWMS M and O 2000a). The UZ flow and transport model is one of several process models abstracted by the Total System Performance Assessment model to evaluate expected performance of the potential repository at Yucca Mountain, Nevada, in terms of radionuclide transport (CRWMS M and O 1998). The net-infiltration model is important for assessing potential repository-system performance because output from this model provides the upper boundary condition for the UZ flow and transport model that is used to generate flow fields for evaluating potential radionuclide transport through the unsaturated zone. Estimates of net infiltration are provided as raster-based, 2-dimensional grids of spatially distributed, time-averaged rates for three different climate stages estimated as likely conditions for the next 10,000 years beyond the present. Each climate stage is represented using a lower bound, a mean, and an upper bound climate and corresponding net-infiltration scenario for representing uncertainty in the characterization of daily climate conditions for each climate stage, as well as potential climate variability within each climate stage. The set of nine raster grid maps provide
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Discards of Danish set nets fisheries in the Kattegat
DEFF Research Database (Denmark)
Savina, Esther; Krag, Ludvig Ahm; Frandsen, Rikke
to the food web. These ecological interactions can be of importance for the surrounding ecosystem, especially regarding small-scale fisheries which take place in relatively shallow waters. Previous studies on gill- or trammel nets discards mostly focus either on commercially valuable fish, or on incidentally...... caught rare or protected species. Data collected by observers aboard commercial fishing vessels gives a first insight into the discards of non-commercial fish and invertebrates in the Danish small-scale set nets fisheries...
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The Virtual Beach Manager Toolset (VB) is a set of decision support software tools developed to help local beach managers make decisions as to when beaches should be closed due to predicted high levels of water borne pathogens. The tools are being developed under the umbrella of...
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The equivalency between logic Petri workflow nets and workflow nets.
Wang, Jing; Yu, ShuXia; Du, YuYue
2015-01-01
Logic Petri nets (LPNs) can describe and analyze batch processing functions and passing value indeterminacy in cooperative systems. Logic Petri workflow nets (LPWNs) are proposed based on LPNs in this paper. Process mining is regarded as an important bridge between modeling and analysis of data mining and business process. Workflow nets (WF-nets) are the extension to Petri nets (PNs), and have successfully been used to process mining. Some shortcomings cannot be avoided in process mining, such as duplicate tasks, invisible tasks, and the noise of logs. The online shop in electronic commerce in this paper is modeled to prove the equivalence between LPWNs and WF-nets, and advantages of LPWNs are presented.
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The Equivalency between Logic Petri Workflow Nets and Workflow Nets
Wang, Jing; Yu, ShuXia; Du, YuYue
2015-01-01
Logic Petri nets (LPNs) can describe and analyze batch processing functions and passing value indeterminacy in cooperative systems. Logic Petri workflow nets (LPWNs) are proposed based on LPNs in this paper. Process mining is regarded as an important bridge between modeling and analysis of data mining and business process. Workflow nets (WF-nets) are the extension to Petri nets (PNs), and have successfully been used to process mining. Some shortcomings cannot be avoided in process mining, such as duplicate tasks, invisible tasks, and the noise of logs. The online shop in electronic commerce in this paper is modeled to prove the equivalence between LPWNs and WF-nets, and advantages of LPWNs are presented. PMID:25821845
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Physical characteristics comparison of virtual wedge device with physical wedge
International Nuclear Information System (INIS)
Cho, Jung Keun; Choi, Kye Sook; Lim, Cheong Hwan; Kim, Jeong Koo; Jung, Hong Ryang; Lee, Jung Ok; Lee, Man Goo
2001-01-01
We compared the characteristics of Siemens virtual wedge device with physical wedges for clinical application. We investigated the characteristics of virtual and physical wedges for various wedge angles (15, 30, 45, and 60) using 6- and 15- MV photon beams. Wedge factors were measured in water using an ion chamber for various field sizes and depths. In case of virtual wedge device, as upper jaw moves during irradiation, wedge angles were estimated by accumulated doses. These measurements were performed at off-axis points perpendicular to the beam central axis in water for a 15 cm x 20 cm radiation field size at the depth of 10 cm. Surface does without and with virtual or physical wedges were measured using a parallel plate ion chamber at surface. Field size was 15 cm * 20 cm and a polystyrene phantom was used. For various field sizes, virtual and physical wedge factors were changed by maximum 2.1% and 3.9%, respectively. For various depths, virtual and physical wedge factors were changed by maximum 1.9% and 2.9%, respectively. No major difference was found between the virtual and physical wedge angles and the difference was within 0.5. Surface dose with physical wedge was reduced by maximum 20% (x-ray beam : 6 MV, wedge angle : 45, SSD : 80 cm) relative to one with virtual wedge or without wedge. Comparison of the characteristics of Siemens virtual wedge device with physical wedges was performed. Depth dependence of virtual wedge factor was smaller than that of physical wedge factor. Virtual and physical wedge factors were nearly independent of field sizes. The accuracy of virtual and physical wedge angles was excellent. Surface dose was found to be reduced using a physical wedge
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Physical characteristics comparison of virtual wedge device with physical wedge
International Nuclear Information System (INIS)
Choi, Dong Rak; Shin, Kyung Hwan; Lee, Kyu Chan; Kim, Dae Yong; Ahn, Yong Chan; Lim, Do Hoon; Kim, Moon Kyung; Huh, Seung Jae
1999-01-01
We have compared the characteristics of Siemens virtual wedge device with physical wedges for clinical application. We investigated the characteristics of virtual and physical wedges for various wedge angles (15, 30, 45, and 60 ) using 6- and 15MV photon beams. Wedge factors were measured in water using an ion chamber for various field sizes and depths. In case of virtual wedge device, as upper jaw moves during irradiation, wedge angles were estimated by accumulated doses. These measurements were performed at off-axis points perpendicular to the beam central axis in water for a 15 cm x 20 cm radiation field size at the depth of 10 cm. Surface doses without and with virtual or physical wedges were measured using a parallel plate ion chamber at surface. Field size was 15 cm x 20 cm and a polystyrene phantom was used. For various field sizes, virtual and physical wedge factors were changed by maximum 2.1% and 3.9%, respectively. For various depths, virtual and physical wedge factors were changed by maximum 1.9% and 2.9%, respectively. No major difference was found between the virtual and physical wedge angles and the difference was within 0.5 .deg. . Surface dose with physical wedge was reduced by maximum 20% (x-ray beam: 6 MV, wedge angle: 45 .deg. , SSD: 80cm) relative to one with virtual wedge or without wedge. Comparison of the characteristics of Siemens virtual wedge device with physical wedges was performed. Depth dependence of virtual wedge factor was smaller than that of physical wedge factor. Virtual and physical wedge factors were nearly independent of field sizes. The accuracy of virtual and physical wedge angles was excellent. Surface dose was found to be reduced using physical wedge
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International Nuclear Information System (INIS)
Lester, G.
1989-01-01
Nonchemical treatments of gamma irradiation (2 Kilograys) and hot water (57°C) and the fungicide imazalil (1000 ppm) were compared with and without shrink-film wrap for effects on decay and physical quality of netted muskmelon fruit stored at 4°C for 0 through 60 days. Gamma irradiation was ineffective in controlling decay and surface molds, and injurious to physical quality by decreasing firmness, increasing fresh weight loss, membrane leakage and vein track browning. Hot water treatment coupled with shrink-film wrap was effective in controlling decay activity and maintaining physical quality up to 20 days storage. Imazalil coupled with shrink-film wrap controlled the incidence and severity of decay and maintained fruit firmness, moisture loss, membrane permeability and vein track browning for almost 60 days storage. (author)
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Murrell, Michael C.; Stanley, Roman S.; Lehrter, John C.; Hagy, James D.
2013-01-01
We conducted a multi-year study of the Louisiana continental shelf (LCS) to better understand the linkages between water column metabolism and the formation of hypoxia (dissolved oxygen Continental Shelf Research, 29: 1861-1872) to estimate net water column metabolism. There was consistent evidence of net heterotrophy, particularly in western transects, and in deeper waters (>40 m depth), indicating a net organic carbon deficit on the LCS. We offer a simple scale argument to suggest that riverine and inshore coastal waters may be significant sources of organic carbon to account for this deficit. This study provided unprecedented, continental shelf scale coverage of heterotrophic metabolism, which is useful for constraining models of oxygen, carbon, and nutrient dynamics along the LCS.
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Optimum Temperatures for Net Primary Productivity of Three Tropical Seagrass Species.
Collier, Catherine J; Ow, Yan X; Langlois, Lucas; Uthicke, Sven; Johansson, Charlotte L; O'Brien, Katherine R; Hrebien, Victoria; Adams, Matthew P
2017-01-01
Rising sea water temperature will play a significant role in responses of the world's seagrass meadows to climate change. In this study, we investigated seasonal and latitudinal variation (spanning more than 1,500 km) in seagrass productivity, and the optimum temperatures at which maximum photosynthesis and net productivity (for the leaf and the whole plant) occurs, for three seagrass species ( Cymodocea serrulata, Halodule uninervis , and Zostera muelleri ). To obtain whole plant net production, photosynthesis, and respiration rates of leaves and the root/rhizome complex were measured using oxygen-sensitive optodes in closed incubation chambers at temperatures ranging from 15 to 43°C. The temperature-dependence of photosynthesis and respiration was fitted to empirical models to obtain maximum metabolic rates and thermal optima. The thermal optimum ( T opt ) for gross photosynthesis of Z. muelleri , which is more commonly distributed in sub-tropical to temperate regions, was 31°C. The T opt for photosynthesis of the tropical species, H. uninervis and C. serrulata , was considerably higher (35°C on average). This suggests that seagrass species are adapted to water temperature within their distributional range; however, when comparing among latitudes and seasons, thermal optima within a species showed limited acclimation to ambient water temperature ( T opt varied by 1°C in C. serrulata and 2°C in H. uninervis , and the variation did not follow changes in ambient water temperature). The T opt for gross photosynthesis were higher than T opt calculated from plant net productivity, which includes above- and below-ground respiration for Z. muelleri (24°C) and H. uninervis ( 33°C), but remained unchanged at 35°C in C. serrulata . Both estimated plant net productivity and T opt are sensitive to the proportion of below-ground biomass, highlighting the need for consideration of below- to above-ground biomass ratios when applying thermal optima to other meadows. The
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Virtual goods recommendations in virtual worlds.
Chen, Kuan-Yu; Liao, Hsiu-Yu; Chen, Jyun-Hung; Liu, Duen-Ren
2015-01-01
Virtual worlds (VWs) are computer-simulated environments which allow users to create their own virtual character as an avatar. With the rapidly growing user volume in VWs, platform providers launch virtual goods in haste and stampede users to increase sales revenue. However, the rapidity of development incurs virtual unrelated items which will be difficult to remarket. It not only wastes virtual global companies' intelligence resources, but also makes it difficult for users to find suitable virtual goods fit for their virtual home in daily virtual life. In the VWs, users decorate their houses, visit others' homes, create families, host parties, and so forth. Users establish their social life circles through these activities. This research proposes a novel virtual goods recommendation method based on these social interactions. The contact strength and contact influence result from interactions with social neighbors and influence users' buying intention. Our research highlights the importance of social interactions in virtual goods recommendation. The experiment's data were retrieved from an online VW platform, and the results show that the proposed method, considering social interactions and social life circle, has better performance than existing recommendation methods.
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Madin, John; Chong, V. C.; Basri, Badrulnizam
2009-06-01
A study was conducted at a fish culture farm in the Jaha River estuary, Malaysia, to examine the structure and development of macrofouling assemblages on floating net-cages. The study was conducted during the dry (August-October 2001) and wet (December-February 2002) seasons. Biofouling on 1.6 cm mesh net panels (size 0.2 m × 2 m) suspended inside (P, T) and outside (O) experimental net-cages was monitored every week until net openings were completely occluded by macrofouling organisms (8 wk and 12 wk for dry and wet seasons respectively). Seven species (6 phyla) of sessile organisms and 23 species (3 phyla) of non-sessile associates were recorded. Macro-colonization of net panels began with the hydroid Plumularia sp. irrespective of season and treatment (P, T, and O), while other species only appeared after 1 or 2 weeks of immersion. Inside net-cages where water flow was slow (mean macroalgae ( Polysiphonia sp.), anthozoans (unidentified anemone), barnacles ( Balanus amphitrite), amphipods ( Gammaropsis sp. & Photis sp.), and tanaids ( Leptognathia sp.) were dominant on the net panels during the dry season. In the wet season, hydroid ( Plumularia sp.), mussel ( Xenostrobus mangle), and nematode abundance were however significant. With stronger water flow (mean ≈ 20 cm s -1) as occurring outside the net-cages, macrofouling assemblages for both seasons comprised mainly Plumularia sp. and Gammaropsis sp. The macrofouling assemblage showed a clear succession of species that occupied different layers of the net panels. The study shows that while organic enrichment and retarded water flow together enhance the development of macrofouling assemblages, salinity, depth, substrate (net) area and species competition specifically influence community structure, colonization, and depth distribution of the macrofouling organisms.
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Controls on the variability of net infiltration to desert sandstone
Heilweil, Victor M.; McKinney, Tim S.; Zhdanov, Michael S.; Watt, Dennis E.
2007-01-01
As populations grow in arid climates and desert bedrock aquifers are increasingly targeted for future development, understanding and quantifying the spatial variability of net infiltration becomes critically important for accurately inventorying water resources and mapping contamination vulnerability. This paper presents a conceptual model of net infiltration to desert sandstone and then develops an empirical equation for its spatial quantification at the watershed scale using linear least squares inversion methods for evaluating controlling parameters (independent variables) based on estimated net infiltration rates (dependent variables). Net infiltration rates used for this regression analysis were calculated from environmental tracers in boreholes and more than 3000 linear meters of vadose zone excavations in an upland basin in southwestern Utah underlain by Navajo sandstone. Soil coarseness, distance to upgradient outcrop, and topographic slope were shown to be the primary physical parameters controlling the spatial variability of net infiltration. Although the method should be transferable to other desert sandstone settings for determining the relative spatial distribution of net infiltration, further study is needed to evaluate the effects of other potential parameters such as slope aspect, outcrop parameters, and climate on absolute net infiltration rates.
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Woolley, Daniel G; Mantini, Dante; Coxon, James P; D'Hooge, Rudi; Swinnen, Stephan P; Wenderoth, Nicole
2015-04-01
Recent work has demonstrated that functional connectivity between remote brain regions can be modulated by task learning or the performance of an already well-learned task. Here, we investigated the extent to which initial learning and stable performance of a spatial navigation task modulates functional connectivity between subregions of hippocampus and striatum. Subjects actively navigated through a virtual water maze environment and used visual cues to learn the position of a fixed spatial location. Resting-state functional magnetic resonance imaging scans were collected before and after virtual water maze navigation in two scan sessions conducted 1 week apart, with a behavior-only training session in between. There was a large significant reduction in the time taken to intercept the target location during scan session 1 and a small significant reduction during the behavior-only training session. No further reduction was observed during scan session 2. This indicates that scan session 1 represented initial learning and scan session 2 represented stable performance. We observed an increase in functional connectivity between left posterior hippocampus and left dorsal caudate that was specific to scan session 1. Importantly, the magnitude of the increase in functional connectivity was correlated with offline gains in task performance. Our findings suggest cooperative interaction occurs between posterior hippocampus and dorsal caudate during awake rest following the initial phase of spatial navigation learning. Furthermore, we speculate that the increase in functional connectivity observed during awake rest after initial learning might reflect consolidation-related processing. © 2014 Wiley Periodicals, Inc.
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Directory of Open Access Journals (Sweden)
Juan Gabriel León Hernández
2009-01-01
Full Text Available Using satellite altimeter radar technology for monitoring changes in water levels at continental scale is a relatively recent ad- vance. Several studies have demonstrated the interest being shown in applying this technology to monitoring the hydrographic patterns of large-scale basins worldwide. The current study presents the inference of time series representing changes in water le- vel for bodies of water by defining virtual gauge stations deduced for two very different rivers in terms of their biophysical and to- pographic characteristics; the two rivers were the Rio Negro in the Brazilian Amazon Basin and the Caqueta River on the Colombian side. The differences between the two rivers revealed the limits of satellite radar altimeter when applied to continental waters (±20cm and ±40 cm precision for Río Negro and Río Caquetá, respectively. However, applying this technology seems very promising, since new missions have been scheduled to be put into orbit by the end of 2008.
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Sartori, Martina; Schiavo, Stefano; Fracasso, Andrea; Riccaboni, Massimo
2017-12-01
The paper investigates how the topological features of the virtual water (VW) network and the size of the associated VW flows are likely to change over time, under different socio-economic and climate scenarios. We combine two alternative models of network formation -a stochastic and a fitness model, used to describe the structure of VW flows- with a gravity model of trade to predict the intensity of each bilateral flow. This combined approach is superior to existing methodologies in its ability to replicate the observed features of VW trade. The insights from the models are used to forecast future VW flows in 2020 and 2050, under different climatic scenarios, and compare them with future water availability. Results suggest that the current trend of VW exports is not sustainable for all countries. Moreover, our approach highlights that some VW importers might be exposed to "imported water stress" as they rely heavily on imports from countries whose water use is unsustainable.
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Real-time recording and classification of eye movements in an immersive virtual environment.
Diaz, Gabriel; Cooper, Joseph; Kit, Dmitry; Hayhoe, Mary
2013-10-10
Despite the growing popularity of virtual reality environments, few laboratories are equipped to investigate eye movements within these environments. This primer is intended to reduce the time and effort required to incorporate eye-tracking equipment into a virtual reality environment. We discuss issues related to the initial startup and provide algorithms necessary for basic analysis. Algorithms are provided for the calculation of gaze angle within a virtual world using a monocular eye-tracker in a three-dimensional environment. In addition, we provide algorithms for the calculation of the angular distance between the gaze and a relevant virtual object and for the identification of fixations, saccades, and pursuit eye movements. Finally, we provide tools that temporally synchronize gaze data and the visual stimulus and enable real-time assembly of a video-based record of the experiment using the Quicktime MOV format, available at http://sourceforge.net/p/utdvrlibraries/. This record contains the visual stimulus, the gaze cursor, and associated numerical data and can be used for data exportation, visual inspection, and validation of calculated gaze movements.
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Wang, Tzu-Ling; Tseng, Yi-Kuan
2018-01-01
The purpose of this study was to investigate the relative effectiveness of experimenting with physical manipulatives alone, virtual manipulatives alone, and virtual preceding physical manipulatives (combination environment) on third-grade students' science achievement and conceptual understanding in the domain of state changes of water, focusing…
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DEFF Research Database (Denmark)
Jensen, Kurt
1987-01-01
The author describes a Petri net model, called coloured Petri nets (CP-nets), by means of which it is possible to describe large systems without having to cope with unnecessary details. The author introduces CP-nets and provide a first impression of their modeling power and the suitability...
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Solar and Net Radiation for Estimating Potential Evaporation from Three Vegetation Canopies
D.M. Amatya; R.W. Skaggs; G.W. Cheschier; G.P. Fernandez
2000-01-01
Solar and net radiation data are frequent/y used in estimating potential evaporation (PE) from various vegetative surfaces needed for water balance and hydrologic modeling studies. Weather parameters such as air temperature, relative humidity, wind speed, solar radiation, and net radiation have been continuously monitored using automated sensors to estimate PE for...
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Net one, net two: the primary care network income statement.
Halley, M D; Little, A W
1999-10-01
Although hospital-owned primary care practices have been unprofitable for most hospitals, some hospitals are achieving competitive advantage and sustainable practice operations. A key to the success of some has been a net income reporting tool that separates practice operating expenses from the costs of creating and operating a network of practices to help healthcare organization managers, physicians, and staff to identify opportunities to improve the network's financial performance. This "Net One, Net Two" reporting allows operations leadership to be held accountable for Net One expenses and strategic leadership to be held accountable for Net Two expenses.
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Virtual marketing in virtual enterprises
Ale Ebrahim, Nader; Fattahi, Hamaid Ali; Golnam, Arash
2008-01-01
Virtualization caused tremendous evolution in the economics of marketing channels, patterns of physical distribution and the structure of distributors and developed a new concept that is known as virtual marketing (VM). VM combines the powerful technologies of interactive marketing and virtual reality. Virtual enterprise (VE) refers to an organization not having a clear physical locus. In other words, VE is an organization distributed geographically and whose work is coordinated through e...
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Virtual Presenters: Towards Interactive Virtual Presentations
Nijholt, Antinus; Cappellini, V.; Hemsley, J.
2005-01-01
We discuss having virtual presenters in virtual environments that present information to visitors of these environments. Some current research is surveyed and we will look in particular to our research in the context of a virtual meeting room where a virtual presenter uses speech, gestures, pointing
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Virtual Worlds for Virtual Organizing
Rhoten, Diana; Lutters, Wayne
The members and resources of a virtual organization are dispersed across time and space, yet they function as a coherent entity through the use of technologies, networks, and alliances. As virtual organizations proliferate and become increasingly important in society, many may exploit the technical architecture s of virtual worlds, which are the confluence of computer-mediated communication, telepresence, and virtual reality originally created for gaming. A brief socio-technical history describes their early origins and the waves of progress followed by stasis that brought us to the current period of renewed enthusiasm. Examination of contemporary examples demonstrates how three genres of virtual worlds have enabled new arenas for virtual organizing: developer-defined closed worlds, user-modifiable quasi-open worlds, and user-generated open worlds. Among expected future trends are an increase in collaboration born virtually rather than imported from existing organizations, a tension between high-fidelity recreations of the physical world and hyper-stylized imaginations of fantasy worlds, and the growth of specialized worlds optimized for particular sectors, companies, or cultures.
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Ramesh Murthy; Stanley J. Zarnoch; P.M. Dougherty
1997-01-01
Repeated measures analysis was used to evaluate the effect of long-term CO2 enhancement on seasonal trends of light-saturated rates of net photosynthesis (Asat) and stomatal conductance to water vapour (gsat) of 9-year-old loblolly pine (Pinus taeda L.; trees grown in a 2x2...
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Simulation of Net Infiltration for Present-Day and Potential Future Climates
Energy Technology Data Exchange (ETDEWEB)
D. Levitt
2004-11-09
The purpose of this model report is to document the infiltration model used to estimate upper-bound, mean, and lower-bound spatially-distributed average annual net infiltration rates for present-day and potential future climates at Yucca Mountain, Nevada. Net infiltration is the component of infiltrated precipitation, snowmelt, or surface water run-on that has percolated below the zone of evapotranspiration as defined by the depth of the effective root zone. The estimates of net infiltration are primarily used for defining the upper boundary condition for the site-scale three-dimensional unsaturated zone (UZ) model. The UZ flow model is one of several process models abstracted by the total system performance assessment (TSPA) model used to evaluate performance of the repository at Yucca Mountain, Nevada. The net-infiltration model is important for assessing repository-system performance because output from this model provides the upper boundary condition for the UZ flow model used to generate flow fields; water percolating downward from the UZ will be the principal means by which radionuclides are potentially released to the saturated zone (SZ). The SZ is the principal pathway to the biosphere where the reasonably maximally exposed individual (RMEI) is exposed to radionuclides.
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Simulation of Net Infiltration for Present-Day and Potential Future Climates
International Nuclear Information System (INIS)
Levitt, D.
2004-01-01
The purpose of this model report is to document the infiltration model used to estimate upper-bound, mean, and lower-bound spatially-distributed average annual net infiltration rates for present-day and potential future climates at Yucca Mountain, Nevada. Net infiltration is the component of infiltrated precipitation, snowmelt, or surface water run-on that has percolated below the zone of evapotranspiration as defined by the depth of the effective root zone. The estimates of net infiltration are primarily used for defining the upper boundary condition for the site-scale three-dimensional unsaturated zone (UZ) model. The UZ flow model is one of several process models abstracted by the total system performance assessment (TSPA) model used to evaluate performance of the repository at Yucca Mountain, Nevada. The net-infiltration model is important for assessing repository-system performance because output from this model provides the upper boundary condition for the UZ flow model used to generate flow fields; water percolating downward from the UZ will be the principal means by which radionuclides are potentially released to the saturated zone (SZ). The SZ is the principal pathway to the biosphere where the reasonably maximally exposed individual (RMEI) is exposed to radionuclides
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National Oceanic and Atmospheric Administration, Department of Commerce — Zooplankton and other data were collected using net casts from T-441 in the Coastal Waters of California. Data were collected from 19 April 1967 to 13 September 1967...
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Bastiaanssen, Wim G.M.; Karimi, Poolad; Rebelo, Lisa-Maria; Duan, Zheng; Senay, Gabriel; Muthuwatte, Lal; Smakhtin, Vladimir
2014-01-01
The increasing competition for water resources requires a better understanding of flows, fluxes, stocks, and the services and benefits related to water consumption. This paper explains how public domain Earth Observation data based on Moderate Resolution Imaging Spectroradiometer (MODIS), Second Generation Meteosat (MSG), Tropical Rainfall Measurement Mission (TRMM) and various altimeter measurements can be used to estimate net water production (rainfall (P) > evapotranspiration (ET)) and net water consumption (ET > P) of Nile Basin agro-ecosystems. Rainfall data from TRMM and the Famine Early Warning System Network (FEWS-NET) RainFall Estimates (RFE) products were used in conjunction with actual evapotranspiration from the Operational Simplified Surface Energy Balance (SSEBop) and ETLook models. Water flows laterally between net water production and net water consumption areas as a result of runoff and withdrawals. This lateral flow between the 15 sub-basins of the Nile was estimated, and partitioned into stream flow and non-stream flow using the discharge data. A series of essential water metrics necessary for successful integrated water management are explained and computed. Net water withdrawal estimates (natural and humanly instigated) were assumed to be the difference between net rainfall (Pnet) and actual evapotranspiration (ET) and some first estimates of withdrawals—without flow meters—are provided. Groundwater-dependent ecosystems withdraw large volumes of groundwater, which exceed water withdrawals for the irrigation sector. There is a strong need for the development of more open-access Earth Observation databases, especially for information related to actual ET. The fluxes, flows and storage changes presented form the basis for a global framework to describe monthly and annual water accounts in ungauged river basins.
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Net ion fluxes and ammonia excretion during transport of Rhamdia quelen juveniles
Directory of Open Access Journals (Sweden)
Luciano de Oliveira Garcia
2015-10-01
Full Text Available The objective of this study was to verify net ion fluxes and ammonia excretion in silver catfish transported in plastic bags at three different loading densities: 221, 286 and 365g L-1 for 5h. A water sample was collected at the beginning and at the end of the transport for analysis of water parameters. There was a significant positive relationship between net ion effluxes and negative relationship between ammonia excretion and loading density, demonstrated by the following equations: Na+: y-24.5-0.27x, r2=0.99, Cl-: y=40.2-0.61x, r2=0.98, K+: y=8.0-27.6x, r2=0.94; ammonia excretion: y=-11.43+0.017x, r2=0.95, where y: net ion flux (mmol kg-1 h-1 or ammonia excretion (mg kg-1h-1 and x: loading density (g. Therefore, the increase of loading density increases net ion loss, but reduces ammonia excretion during the transport of silver catfish, indicating the possibility of ammonia accumulation
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Water conservation through trade: the case of Kenya
Mekonnen, Mesfin; Hoekstra, Arjen Ysbert
2014-01-01
This study quantifies and maps the water footprint of Kenya from both production and consumption perspectives and estimates the country’s virtual water export and import. Kenya’s virtual water export related to trade in agricultural products was 4.1 km3/y; its virtual water import was 4.0 km3/y. The
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QUAL-NET, a high temporal-resolution eutrophication model for large hydrographic networks
Minaudo, Camille; Curie, Florence; Jullian, Yann; Gassama, Nathalie; Moatar, Florentina
2018-04-01
To allow climate change impact assessment of water quality in river systems, the scientific community lacks efficient deterministic models able to simulate hydrological and biogeochemical processes in drainage networks at the regional scale, with high temporal resolution and water temperature explicitly determined. The model QUALity-NETwork (QUAL-NET) was developed and tested on the Middle Loire River Corridor, a sub-catchment of the Loire River in France, prone to eutrophication. Hourly variations computed efficiently by the model helped disentangle the complex interactions existing between hydrological and biological processes across different timescales. Phosphorus (P) availability was the most constraining factor for phytoplankton development in the Loire River, but simulating bacterial dynamics in QUAL-NET surprisingly evidenced large amounts of organic matter recycled within the water column through the microbial loop, which delivered significant fluxes of available P and enhanced phytoplankton growth. This explained why severe blooms still occur in the Loire River despite large P input reductions since 1990. QUAL-NET could be used to study past evolutions or predict future trajectories under climate change and land use scenarios.
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QUAL-NET, a high temporal-resolution eutrophication model for large hydrographic networks
Directory of Open Access Journals (Sweden)
C. Minaudo
2018-04-01
Full Text Available To allow climate change impact assessment of water quality in river systems, the scientific community lacks efficient deterministic models able to simulate hydrological and biogeochemical processes in drainage networks at the regional scale, with high temporal resolution and water temperature explicitly determined. The model QUALity-NETwork (QUAL-NET was developed and tested on the Middle Loire River Corridor, a sub-catchment of the Loire River in France, prone to eutrophication. Hourly variations computed efficiently by the model helped disentangle the complex interactions existing between hydrological and biological processes across different timescales. Phosphorus (P availability was the most constraining factor for phytoplankton development in the Loire River, but simulating bacterial dynamics in QUAL-NET surprisingly evidenced large amounts of organic matter recycled within the water column through the microbial loop, which delivered significant fluxes of available P and enhanced phytoplankton growth. This explained why severe blooms still occur in the Loire River despite large P input reductions since 1990. QUAL-NET could be used to study past evolutions or predict future trajectories under climate change and land use scenarios.
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Numerical study on the hydrodynamic characteristics of biofouled full-scale net cage
Bi, Chun-wei; Zhao, Yun-peng; Dong, Guo-hai
2015-06-01
The effect of biofouling on the hydrodynamic characteristics of the net cage is of particular interest as biofouled nettings can significantly reduce flow of well-oxygenated water reaching the stocked fish. For computational efficiency, the porous-media fluid model is proposed to simulate flow through the biofouled plane net and full-scale net cage. The porous coefficients of the porous-media fluid model can be determined from the quadratic-function relationship between the hydrodynamic forces on a plane net and the flow velocity using the least squares method. In this study, drag forces on and flow fields around five plane nets with different levels of biofouling are calculated by use of the proposed model. The numerical results are compared with the experimental data of Swift et al. (2006) and the effectiveness of the numerical model is presented. On that basis, flow through full-scale net cages with the same level of biofouling as the tested plane nets are modeled. The flow fields inside and around biofouled net cages are analyzed and the drag force acting on a net cage is estimated by a control volume analysis method. According to the numerical results, empirical formulas of reduction in flow velocity and load on a net cage are derived as function of drag coefficient of the corresponding biofouled netting.
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Water footprint characteristic of less developed water-rich regions: Case of Yunnan, China.
Qian, Yiying; Dong, Huijuan; Geng, Yong; Zhong, Shaozhuo; Tian, Xu; Yu, Yanhong; Chen, Yihui; Moss, Dana Avery
2018-03-30
Rapid industrialization and urbanization pose pressure on water resources in China. Virtual water trade proves to be an increasingly useful tool in water stress alleviation for water-scarce regions, while bringing opportunities and challenges for less developed water-rich regions. In this study, Yunnan, a typical province in southwest China, was selected as the case study area to explore its potential in socio-economic development in the context of water sustainability. Both input-output analysis and structural decomposition analysis on Yunnan's water footprint for the period of 2002-2012 were performed at not only an aggregated level but also a sectoral level. Results show that although the virtual water content of all economic sectors decreased due to technological progress, Yunnan's total water footprint still increased as a result of economic scale expansion. From the sectoral perspective, sectors with large water footprints include construction sector, agriculture sector, food manufacturing & processing sector, and service sector, while metal products sector and food manufacturing & processing sector were the major virtual water exporters, and textile & clothing sector and construction sector were the major importers. Based on local conditions, policy suggestions were proposed, including economic structure and efficiency optimization, technology promotion and appropriate virtual water trade scheme. This study provides valuable insights for regions facing "resource curse" by exploring potential socio-economic progress while ensuring water security. Copyright © 2018 Elsevier Ltd. All rights reserved.
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Sensorial Virtualization: Coupling Gaming and Virtual Environment
Garbaya, S.; Miraoui, C.; Wendrich, Robert E.; Lim, T.; Stanescu, I.A.; Hauge, J.B.
2014-01-01
Virtual reality and virtualization are currently used to design complex systems and demonstrate that they represent the functionalities of real systems. However, the design refinement of the virtual environment (VE) and distributed virtual environment (DVE) are still time consuming and costly, as it
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Doell, Petra; Hoffmann-Dobrev, Heike; Portmann, Felix T.; Siebert, Stefan; Eicker, Annette; Rodell, Matthew; Strassberg, Gil
2011-01-01
Humans have strongly impacted the global water cycle, not only water flows but also water storage. We have performed a first global-scale analysis of the impact of water withdrawals on water storage variations, using the global water resources and use model WaterGAP. This required estimation of fractions of total water withdrawals from groundwater, considering five water use sectors. According to our assessment, the source of 35% of the water withdrawn worldwide (4300 cubic km/yr during 1998-2002) is groundwater. Groundwater contributes 42%, 36% and 27% of water used for irrigation, households and manufacturing, respectively, while we assume that only surface water is used for livestock and for cooling of thermal power plants. Consumptive water use was 1400 cubic km/yr during 1998-2002. It is the sum of the net abstraction of 250 cubic km/yr of groundwater (taking into account evapotranspiration and return flows of withdrawn surface water and groundwater) and the net abstraction of 1150 km3/yr of surface water. Computed net abstractions indicate, for the first time at the global scale, where and when human water withdrawals decrease or increase groundwater or surface water storage. In regions with extensive surface water irrigation, such as Southern China, net abstractions from groundwater are negative, i.e. groundwater is recharged by irrigation. The opposite is true for areas dominated by groundwater irrigation, such as in the High Plains aquifer of the central USA, where net abstraction of surface water is negative because return flow of withdrawn groundwater recharges the surface water compartments. In intensively irrigated areas, the amplitude of seasonal total water storage variations is generally increased due to human water use; however, in some areas, it is decreased. For the High Plains aquifer and the whole Mississippi basin, modeled groundwater and total water storage variations were compared with estimates of groundwater storage variations based on
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A Water-Withdrawal Input-Output Model of the Indian Economy.
Bogra, Shelly; Bakshi, Bhavik R; Mathur, Ritu
2016-02-02
Managing freshwater allocation for a highly populated and growing economy like India can benefit from knowledge about the effect of economic activities. This study transforms the 2003-2004 economic input-output (IO) table of India into a water withdrawal input-output model to quantify direct and indirect flows. This unique model is based on a comprehensive database compiled from diverse public sources, and estimates direct and indirect water withdrawal of all economic sectors. It distinguishes between green (rainfall), blue (surface and ground), and scarce groundwater. Results indicate that the total direct water withdrawal is nearly 3052 billion cubic meter (BCM) and 96% of this is used in agriculture sectors with the contribution of direct green water being about 1145 BCM, excluding forestry. Apart from 727 BCM direct blue water withdrawal for agricultural, other significant users include "Electricity" with 64 BCM, "Water supply" with 44 BCM and other industrial sectors with nearly 14 BCM. "Construction", "miscellaneous food products"; "Hotels and restaurants"; "Paper, paper products, and newsprint" are other significant indirect withdrawers. The net virtual water import is found to be insignificant compared to direct water used in agriculture nationally, while scarce ground water associated with crops is largely contributed by northern states.
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Application of deconvolution interferometry with both Hi-net and KiK-net data
Nakata, N.
2013-12-01
Application of deconvolution interferometry to wavefields observed by KiK-net, a strong-motion recording network in Japan, is useful for estimating wave velocities and S-wave splitting in the near surface. Using this technique, for example, Nakata and Snieder (2011, 2012) found changed in velocities caused by Tohoku-Oki earthquake in Japan. At the location of the borehole accelerometer of each KiK-net station, a velocity sensor is also installed as a part of a high-sensitivity seismograph network (Hi-net). I present a technique that uses both Hi-net and KiK-net records for computing deconvolution interferometry. The deconvolved waveform obtained from the combination of Hi-net and KiK-net data is similar to the waveform computed from KiK-net data only, which indicates that one can use Hi-net wavefields for deconvolution interferometry. Because Hi-net records have a high signal-to-noise ratio (S/N) and high dynamic resolution, the S/N and the quality of amplitude and phase of deconvolved waveforms can be improved with Hi-net data. These advantages are especially important for short-time moving-window seismic interferometry and deconvolution interferometry using later coda waves.
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Piber, Dominique; Schultebraucks, Katharina; Mueller, Sven C; Deuter, Christian Eric; Wingenfeld, Katja; Otte, Christian
2016-12-01
Stress hormones such as cortisol are known to influence a wide range of cognitive functions, including hippocampal based spatial memory. In the brain, cortisol acts via two different receptors: the glucocorticoid (GR) and the mineralocorticoid receptor (MR). As the MR has a high density in the hippocampus, we examined the effects of pharmacological MR stimulation on spatial memory. Eighty healthy participants (40 women, 40 men, mean age=23.9years±SD=3.3) completed the virtual Morris Water Maze (vMWM) task to test spatial encoding and spatial memory retrieval after receiving 0.4mg fludrocortisone, a MR agonist, or placebo. There was no effect of MR stimulation on spatial encoding during the vMWM task. However, participants who received fludrocortisone exhibited improved spatial memory retrieval performance. There was neither a main effect of sex nor a sex-by-treatment interaction. In young healthy participants, MR stimulation improved hippocampal based spatial memory retrieval in a virtual Morris Water Maze task. Our study not only confirms the importance of MR function in spatial memory, but suggests beneficial effects of acute MR stimulation on spatial memory retrieval in humans. Copyright © 2016 Elsevier Inc. All rights reserved.
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Intelligent Controls for Net-Zero Energy Buildings
Energy Technology Data Exchange (ETDEWEB)
Li, Haorong; Cho, Yong; Peng, Dongming
2011-10-30
The goal of this project is to develop and demonstrate enabling technologies that can empower homeowners to convert their homes into net-zero energy buildings in a cost-effective manner. The project objectives and expected outcomes are as follows: • To develop rapid and scalable building information collection and modeling technologies that can obtain and process “as-built” building information in an automated or semiautomated manner. • To identify low-cost measurements and develop low-cost virtual sensors that can monitor building operations in a plug-n-play and low-cost manner. • To integrate and demonstrate low-cost building information modeling (BIM) technologies. • To develop decision support tools which can empower building owners to perform energy auditing and retrofit analysis. • To develop and demonstrate low-cost automated diagnostics and optimal control technologies which can improve building energy efficiency in a continual manner.
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THE DEVELOPMENT OF MARINE SPATIAL PLANNING AND ITS APPLICATION FOR FLOATING FISH NET CULTURE
Directory of Open Access Journals (Sweden)
Dewayany Sutrisno
2017-01-01
Full Text Available Marine spatial planning has become the crucial issues for an archipelagic state such as Indonesia. The global market demand on marine economic species has been initiated the exploitation of the marine species which will become the hindrance in maintaining the sustainable marine biodiversity. Besides that, the degradation of marine species will also become the problem for traditional fishermen. Therefore, a model has to be employed to spatially manage the coastal waters as the alternative for fishermen activities during closed seasons, such as floating fish net culture. The aim of this study was to develop marine spatial planning model based on ecological approach in order to identify the potentiality of marine waters for marine culture such as floating fish net culture. The method for the model consisted of social assessment using the Delphi for developing the rule of marine planning for floating fish net culture and the spatial analysis technique for determining the model of marine spatial planning for floating fish net culture. The area of Kupang Bay waters, East Nusa Tenggara was used as the study area. The result indicated that the model can be used to sustainable marine spatial planning, especially for floating fish net culture. The model considered the aspects of potential area for marine culture, the management of zonation and transportation lanes, the conservation and protected area and the strategic area. Application in Kupang bay illustrated the aspect of technology input such as raceways since the majority of the area of Kupang Bay waters is classified as medium potential. Further research still needs to optimum the application of model to others marine area.
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Environmental impact analysis of aquaculture in net cages in a ...
African Journals Online (AJOL)
Environmental impact analysis of aquaculture in net cages in a Brazilian water reservoir, based in zooplankton communities. Maria Cristina Crispim, Karla Patrícia Ponte Araújo, Hênio do Nascimento Melo Júnior ...
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Land-Water-Food Nexus and indications of crop adjustment for water shortage solution.
Ren, Dandan; Yang, Yonghui; Yang, Yanmin; Richards, Keith; Zhou, Xinyao
2018-06-01
While agriculture places the greatest demand on water resources, increasing agricultural production is worsening a global water shortage. Reducing the cultivation of water-consuming crops may be the most effective way to reduce agricultural water use. However, when also taking food demand into consideration, sustaining the balance between regional water and food securities is a growing challenge. This paper addresses this task for regions where water is unsustainable for food production (Beijing-Tianjin-Hebei Region for example) by: (i) assessing the different effects of wheat and maize on water use; (ii) analyzing virtual water and virtual land flows associated with food imports and exports between Beijing-Tianjin-Hebei and elsewhere in China; (iii) identifying sub-regions where grain is produced using scarce water resources but exported to other regions; and (iv) analyzing the potentiality for mitigating water shortage via Land-Water-Food Nexus. In the Beijing-Tianjin-Hebei Region, the study reveals that 29.76 bn m 3 of virtual water (10.81 bn m 3 of blue virtual water) are used by wheat and maize production and 8.77 bn m 3 of virtual water used in nearly 2 million ha of cropland to overproduce 12 million ton of maize for external food consumption. As an importing-based sub-region with high population density, Beijing & Tianjin imported mostly grain (wheat and maize) from Shandong Province. Then, Hebei Province, as an exporting-based sub-region with severe water shortage, overproduced too much grain for other regions, which aggravated the water crisis. To achieve an integrated and sustainable development of the Beijing-Tianjin-Hebei Region, Hebei Province should stop undertaking the breadbasket role for Beijing & Tianjin and pay more attention to groundwater depletion. The analysis of the Land-Water-Food Nexus indicates how shifts in cultivated crops can potentially solve the overuse of water resources without adverse effects on food supply
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Land-Water-Food Nexus and Indications of Crop Adjustment for Water Shortage Solution
Yang, Y.; Ren, D.; Zhou, X.
2017-12-01
Agriculture places the greatest demand on water resources, and increasing agricultural production is worsening a global water shortage. Reducing the cultivation of water-consuming crops may be the most effective way to reduce agricultural water use. However, when also taking food demand into consideration, sustaining the balance between regional water and food securities is a growing challenge. This paper addresses this task for regions where water is unsustainable for food production (Beijing-Tianjin-Hebei Region for example), by (i) assessing the different effects of wheat and maize on water use; (ii) analyzing virtual water and virtual land flows associated with food imports and exports between Beijing-Tianjin-Hebei and elsewhere in China; (iii) identifying sub-regions where grain are produced using scarce water resources but exported to other regions. (iv) analyzing the potentiality for mitigating water shortage via Land-Water-Food Nexus. In the Beijing-Tianjin-Hebei Region, the study reveals that 29.76 bn m3 of virtual water (10.81 bn m3 of blue virtual water) are used by wheat and maize production and nearly 2 million ha of cropland using 8.77 bn m3 of virtual water overproduced 12 million ton of maize for external food consumption. As an importing-based sub-region with high population density, Beijing and Tianjin (BT) imported mostly grain (wheat and maize) from Shandong (SD). Whereas, Hebei (HB), as an exporting-based sub-region with sever water shortage, overproduced too much grain for other regions (like Central area), which aggravated water crisis. To achieve Beijing-Tianjin-Hebei's integrated and sustainable development, HB should not undertake the breadbasket role for BT but pay more attention to groundwater depletion. The analysis of the Land-Water-Food Nexus indicates how shifts in the cultivated crops can potentially solve the overuse of water resources without adverse effect on food supply, and provides meaningful information to support policy
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Manoharan, Prabu; Chennoju, Kiranmai; Ghoshal, Nanda
2015-07-01
BACE1 is an attractive target in Alzheimer's disease (AD) treatment. A rational drug design effort for the inhibition of BACE1 is actively pursued by researchers in both academic and pharmaceutical industries. This continued effort led to the steady accumulation of BACE1 crystal structures, co-complexed with different classes of inhibitors. This wealth of information is used in this study to develop target specific proteochemometric models and these models are exploited for predicting the prospective BACE1 inhibitors. The models developed in this study have performed excellently in predicting the computationally generated poses, separately obtained from single and ensemble docking approaches. The simple protein-ligand contact (SPLC) model outperforms other sophisticated high end models, in virtual screening performance, developed during this study. In an attempt to account for BACE1 protein active site flexibility information in predictive models, we included the change in the area of solvent accessible surface and the change in the volume of solvent accessible surface in our models. The ensemble and single receptor docking results obtained from this study indicate that the structural water mediated interactions improve the virtual screening results. Also, these waters are essential for recapitulating bioactive conformation during docking study. The proteochemometric models developed in this study can be used for the prediction of BACE1 inhibitors, during the early stage of AD drug discovery.
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Optimum Temperatures for Net Primary Productivity of Three Tropical Seagrass Species
Collier, Catherine J.; Ow, Yan X.; Langlois, Lucas; Uthicke, Sven; Johansson, Charlotte L.; O'Brien, Katherine R.; Hrebien, Victoria; Adams, Matthew P.
2017-01-01
Rising sea water temperature will play a significant role in responses of the world's seagrass meadows to climate change. In this study, we investigated seasonal and latitudinal variation (spanning more than 1,500 km) in seagrass productivity, and the optimum temperatures at which maximum photosynthesis and net productivity (for the leaf and the whole plant) occurs, for three seagrass species (Cymodocea serrulata, Halodule uninervis, and Zostera muelleri). To obtain whole plant net production...
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A novel method for direct localized sound speed measurement using the virtual source paradigm
DEFF Research Database (Denmark)
Byram, Brett; Trahey, Gregg E.; Jensen, Jørgen Arendt
2007-01-01
) mediums. The inhomogeneous mediums were arranged as an oil layer, one 6 mm thick and the other 11 mm thick, on top of a water layer. To complement the phantom studies, sources of error for spatial registration of virtual detectors were simulated. The sources of error presented here are multiple sound...... registered virtual detector. Between a pair of registered virtual detectors a spherical wave is propagated. By beamforming the received data the time of flight between the two virtual sources can be calculated. From this information the local sound speed can be estimated. Validation of the estimator used...... both phantom and simulation results. The phantom consisted of two wire targets located near the transducer's axis at depths of 17 and 28 mm. Using this phantom the sound speed between the wires was measured for a homogeneous (water) medium and for two inhomogeneous (DB-grade castor oil and water...
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Olzak, Thomas; Boomer, Jason; Keefer, Robert M
2010-01-01
Microsoft Virtualization helps you understand and implement the latest virtualization strategies available with Microsoft products. This book focuses on: Server Virtualization, Desktop Virtualization, Application Virtualization, and Presentation Virtualization. Whether you are managing Hyper-V, implementing desktop virtualization, or even migrating virtual machines, this book is packed with coverage on all aspects of these processes. Written by a talented team of Microsoft MVPs, Microsoft Virtualization is the leading resource for a full installation, migration, or integration of virtual syste
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Artisanal fishing net float loss and a proposal for a float design solution
Directory of Open Access Journals (Sweden)
Paulo de Tarso Chaves
2016-03-01
Full Text Available Abstract Plastic floats from fishing nets are commonly found washed up on beaches in southern Brazil. They are usually broken and show signs of having been repaired. Characteristics of floats and interviews with fishermen suggest two main causes of float loss. First, collisions between active gear, bottom trawl nets for shrimp, and passive gear, drift nets for fish, destroy nets and release fragments of them, including floats. Second, the difficulty with which floats are inserted on the float rope of the nets when they are used near the surface. Floats are inserted to replace damaged or lost floats, or they may be removed if it is desired that the nets be used in deeper waters. Floats may thus be poorly fixed to the cables and lost. Here a new float design that offers greater safety in use and for the replacement of floats is described and tested.
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RadNet Radiological Air Monitoring Network
International Nuclear Information System (INIS)
Scott Telofski, J.; Askren, D.R.; Petko, Ch.M.; Fraass, R.G.
2010-01-01
The United States Environmental Protection Agency operates a national environmental radiation monitoring program called RadNet. RadNet monitors airborne particulates, precipitation, milk, and drinking water for radiation levels. The primary purpose of the original program in the 1950's and 1960's was to collect and analyze samples in various media to assess the effects of radioactive fallout from above-ground nuclear weapon testing. As above-ground testing diminished in the 1970's, the program, especially the air network, became critical in evaluating effects of other types of nuclear incidents, such as the nuclear reactor accident at Chernobyl, as well as monitoring trends in environmental radioactive contamination. The value of rapid data collection subsequent to such incidents led to the consideration of developing air monitors with radiation detectors and telecommunication equipment for real-time radiation measurement. The strengthened United States homeland security posture after 2001 led to production and installation of the current real-time RadNet air monitors. There are now 118 stationary, continuously operating air monitoring stations and 40 mobile air monitors for site specific monitoring. The stationary air monitors include radiation detectors, meteorological sensors, a high-volume air sampler, and communication devices for hourly data transfers. When unusual levels are detected, scientists download a full sodium iodide detector spectrum for analysis. The real-time data collected by RadNet stationary systems permit rapid identification and quantification of airborne nuclides with sufficient sensitivity to provide critical information to help determine protective actions. The data also may help to rapidly refine long-range radioactive plume models and estimate exposure to the population. This paper provides an overview of the airborne particulate monitoring conducted during above-ground nuclear weapon testing, summarizes the uses of data from the program
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Virtual Library: An essential component of virtual education
Directory of Open Access Journals (Sweden)
M zarghani
2015-06-01
Full Text Available Abstract Introduction: Library is one of the essential elements of universities which provide some important educational needs of students. Virtual education can not be exempted and virtual libraries are important support for virtual training programs. The purpose of this study is to evaluate the viewpoint of administrators and students in virtual education centers about the virtual library, its role and resources. Methods: This study was a descriptive survey. The research instrument was a researcher made questionnaire that its validity and reliability was confirmed. The study population consisted of 19 virtual training centers in Tehran city. Out of 19 centers, simple randomized sampling was done in five Centers. The sample size was 360 students. Data collection was conducted online and descriptive statistics using SPSS 18 and Excel software were used. Results: The results showed that viewpoints of administrators and students about the mission and services of virtual libraries in some cases were similar and in some cases were different. One of the administrators’ reasons for setting up a virtual learning system was lifelong learning, and lack of knowledge about virtual libraries was the reason for inadequate use of virtual libraries. The best format of virtual library from the administrators’ and students’ viewpoint, was portal document format (PDF. Conclusion: One of the most important function of a virtual library, is lifelong learning and empowering users to provide information and educational needs. The main reason for not setting up a virtual library is t lack of knowledge about it.
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CLIMATIC FORECASTING OF NET INFILTRATION AT YUCCA MOUNTAIN, USING ANALOGUE METEOROLOGICAL DATA
International Nuclear Information System (INIS)
B. Faybishenko
2005-01-01
Net infiltration is a key hydrologic parameter that controls the rate of deep percolation through the unsaturated zone, the groundwater recharge, radionuclide transport, and seepage into the underground tunnels. Because net infiltration is largely affected by climatic conditions, future changes in climatic conditions will potentially alter net infiltration. The objectives of this presentation are to: (1) Present a conceptual model and a semi-empirical approach for regional, climatic forecasting of net infiltration, based on the precipitation and temperature data from analogue meteorological stations, and (2) Demonstrate the results of forecasting net infiltration for future climates--interglacial, monsoon and glacial--over the Yucca Mountain region for the period of 500,000 years. Calculations of the net infiltration were performed using a modified Budyko's water-balance model, for which potential evapotranspiration was evaluated from the temperature-based Thornthwaite formula. (Both Budyko's and Thornthwaite's formulae have been used broadly in hydrological studies.) The results of calculations were used for ranking net infiltration, along with the aridity and precipitation-effectiveness (P-E) indexes, for future climatic scenarios. Using this approach, we determined a general trend of increasing net infiltration from the present-day (interglacial) climate to monsoon, intermediate (glacial transition), and then to the glacial climate. Ranking of the aridity and P-E indexes is practically the same as that of net infiltration. The validation of the computed net infiltration rates yielded a good match with other field and modeling study results of groundwater recharge and net infiltration evaluation
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Virtual Reality and the Virtual Library.
Oppenheim, Charles
1993-01-01
Explains virtual reality, including proper and improper uses of the term, and suggests ways that libraries might be affected by it. Highlights include elements of virtual reality systems; possible virtual reality applications, including architecture, the chemical industry, transport planning, armed forces, and entertainment; and the virtual…
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From virtual environment to virtual community
Nijholt, Antinus; Terano, Takao; Nishida, Toyoaki; Namatame, Akira; Tsumoto, Syusaku; Ohsawa, Yukido; Washio, Takashi
2001-01-01
We discuss a virtual reality theater environment and its transition to a virtual community by adding domain agents and by allowing multiple users to visit this environment. The environment has been built using VRML (Virtual Reality Modeling Language). We discuss how our ideas about this environment
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DEFF Research Database (Denmark)
Savin, Andrej
2017-01-01
Repealing “net neutrality” in the US will have no bearing on Internet freedom or security there or anywhere else.......Repealing “net neutrality” in the US will have no bearing on Internet freedom or security there or anywhere else....
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Annotating Coloured Petri Nets
DEFF Research Database (Denmark)
Lindstrøm, Bo; Wells, Lisa Marie
2002-01-01
Coloured Petri nets (CP-nets) can be used for several fundamentally different purposes like functional analysis, performance analysis, and visualisation. To be able to use the corresponding tool extensions and libraries it is sometimes necessary to include extra auxiliary information in the CP......-net. An example of such auxiliary information is a counter which is associated with a token to be able to do performance analysis. Modifying colour sets and arc inscriptions in a CP-net to support a specific use may lead to creation of several slightly different CP-nets – only to support the different uses...... of the same basic CP-net. One solution to this problem is that the auxiliary information is not integrated into colour sets and arc inscriptions of a CP-net, but is kept separately. This makes it easy to disable this auxiliary information if a CP-net is to be used for another purpose. This paper proposes...
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Riva, G; Bacchetta, M; Baruffi, M; Borgomainerio, E; Defrance, C; Gatti, F; Galimberti, C; Fontaneto, S; Marchi, S; Molinari, E; Nugues, P; Rinaldi, S; Rovetta, A; Ferretti, G S; Tonci, A; Wann, J; Vincelli, F
1999-01-01
Due, in large part, to the significant advances in PC hardware that have been made over the last 3 years, PC-based virtual environments are approaching reality. Virtual Reality Environments for Psychoneurophysiological Assessment and Rehabilitation (VREPAR) are two European Community funded projects (Telematics for health-HC 1053/HC 1055, http:// www.psicologia.net) that are trying to develop a PC-based virtual reality system (PC-VRS) for the medical market that can be marketed at a price that is accessible to its possible endusers (hospitals, universities, and research centres) and that would have the modular, connectability, and interoperability characteristics that the existing systems lack. In particular, the projects are developing three hardware/software modules for the application of the PCVRS in psycho-neuro-physiological assessment and rehabilitation. The chosen development areas are eating disorders (bulimia, anorexia, and obesity), movement disorders (Parkinson's disease and torsion dystonia) and stroke disorders (unilateral neglect and hemiparesis). This article describes the rationale of the modules and the preliminary results obtained.
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Open web system of Virtual labs for nuclear and applied physics
International Nuclear Information System (INIS)
Saldikov, I S; Afanasyev, V V; Petrov, V I; Ternovykh, M Yu
2017-01-01
An example of virtual lab work on unique experimental equipment is presented. The virtual lab work is software based on a model of real equipment. Virtual labs can be used for educational process in nuclear safety and analysis field. As an example it includes the virtual lab called “Experimental determination of the material parameter depending on the pitch of a uranium-water lattice”. This paper included general description of this lab. A description of a database on the support of laboratory work on unique experimental equipment which is included this work, its concept development are also presented. (paper)
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RadNet Map Interface for Near-Real-Time Radiation Monitoring Data
U.S. Environmental Protection Agency — RadNet is a national network of monitoring stations that regularly collect air, precipitation, drinking water, and milk samples for analysis of radioactivity. The...
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DEFF Research Database (Denmark)
Horn, Heiko; Lawrence, Michael S; Chouinard, Candace R
2018-01-01
Methods that integrate molecular network information and tumor genome data could complement gene-based statistical tests to identify likely new cancer genes; but such approaches are challenging to validate at scale, and their predictive value remains unclear. We developed a robust statistic (Net......Sig) that integrates protein interaction networks with data from 4,742 tumor exomes. NetSig can accurately classify known driver genes in 60% of tested tumor types and predicts 62 new driver candidates. Using a quantitative experimental framework to determine in vivo tumorigenic potential in mice, we found that Net......Sig candidates induce tumors at rates that are comparable to those of known oncogenes and are ten-fold higher than those of random genes. By reanalyzing nine tumor-inducing NetSig candidates in 242 patients with oncogene-negative lung adenocarcinomas, we find that two (AKT2 and TFDP2) are significantly amplified...
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Maurer, M
2009-05-01
A specific net present value (SNPV) approach is introduced as a criterion in economic engineering decisions. The SNPV expresses average costs, including the growth rate and plant utilisation over the planning horizon, factors that are excluded from a standard net present value approach. The use of SNPV favours alternatives that are cheaper per service unit and are therefore closer to the costs that a user has to cover. It also shows that demand growth has a similar influence on average costs as an economy of scale. In a high growth scenario, solutions providing less idle capacity can have higher present value costs and still be economically favourable. The SNPV approach is applied in two examples to calculate acceptable additional costs for modularisation and comparable costs for on-site treatment (OST) as an extreme form of modularisation. The calculations show that: (i) the SNPV approach is suitable for quantifying the comparable costs of an OST system in a different scenario; (ii) small systems with projected high demand growth rates and high real interest rates are the most probable entry market for OST water treatment systems; (iii) operating expenses are currently the main economic weakness of membrane-based wastewater OST systems; and (iv) when high growth in demand is expected, up to 100% can be additionally invested in modularisation and staging the expansion of a treatment plant.
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In-beam experience with a highly granular DAQ and control network: TrbNet
International Nuclear Information System (INIS)
Michel, J; Korcyl, G; Maier, L; Traxler, M
2013-01-01
Virtually all Data Acquisition Systems (DAQ) for nuclear and particle physics experiments use a large number of Field Programmable Gate Arrays (FPGAs) for data transport and more complex tasks as pattern recognition and data reduction. All these FPGAs in a large system have to share a common state like a trigger number or an epoch counter to keep the system synchronized for a consistent event/epoch building. Additionally, the collected data has to be transported with high bandwidth, optionally via the ubiquitous Ethernet protocol. Furthermore, the FPGAs' internal states and configuration memories have to be accessed for control and monitoring purposes. Another requirement for a modern DAQ-network is the fault-tolerance for intermittent data errors in the form of automatic retransmission of faulty data. As FPGAs suffer from Single Event Effects when exposed to ionizing particles, the system has to deal with failing FPGAs. The TrbNet protocol was developed taking all these requirements into account. Three virtual channels are merged on one physical medium: The trigger/epoch information is transported with the highest priority. The data channel is second in the priority order, while the control channel is the last. Combined with a small frame size of 80 bit this guarantees a low latency data transport: A system with 100 front-ends can be built with a one-way latency of 2.2 us. The TrbNet-protocol was implemented in each of the 550 FPGAs of the HADES upgrade project and has been successfully used during the Au+Au campaign in April 2012. With 2⋅10 6 /s Au-ions and 3% interaction ratio the accepted trigger rate is 10 kHz while data is written to storage with 150 MBytes/s. Errors are reliably mitigated via the implemented retransmission of packets and auto-shut-down of individual links. TrbNet was also used for full monitoring of the FEE status. The network stack is written in VHDL and was successfully deployed on various Lattice and Xilinx devices. The TrbNet is also
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In-beam experience with a highly granular DAQ and control network: TrbNet
Michel, J.; Korcyl, G.; Maier, L.; Traxler, M.
2013-02-01
Virtually all Data Acquisition Systems (DAQ) for nuclear and particle physics experiments use a large number of Field Programmable Gate Arrays (FPGAs) for data transport and more complex tasks as pattern recognition and data reduction. All these FPGAs in a large system have to share a common state like a trigger number or an epoch counter to keep the system synchronized for a consistent event/epoch building. Additionally, the collected data has to be transported with high bandwidth, optionally via the ubiquitous Ethernet protocol. Furthermore, the FPGAs' internal states and configuration memories have to be accessed for control and monitoring purposes. Another requirement for a modern DAQ-network is the fault-tolerance for intermittent data errors in the form of automatic retransmission of faulty data. As FPGAs suffer from Single Event Effects when exposed to ionizing particles, the system has to deal with failing FPGAs. The TrbNet protocol was developed taking all these requirements into account. Three virtual channels are merged on one physical medium: The trigger/epoch information is transported with the highest priority. The data channel is second in the priority order, while the control channel is the last. Combined with a small frame size of 80 bit this guarantees a low latency data transport: A system with 100 front-ends can be built with a one-way latency of 2.2 us. The TrbNet-protocol was implemented in each of the 550 FPGAs of the HADES upgrade project and has been successfully used during the Au+Au campaign in April 2012. With 2ṡ106/s Au-ions and 3% interaction ratio the accepted trigger rate is 10 kHz while data is written to storage with 150 MBytes/s. Errors are reliably mitigated via the implemented retransmission of packets and auto-shut-down of individual links. TrbNet was also used for full monitoring of the FEE status. The network stack is written in VHDL and was successfully deployed on various Lattice and Xilinx devices. The TrbNet is also
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Liberty, Jesse
2009-01-01
Learning Visual Basic .NET is a complete introduction to VB.NET and object-oriented programming. By using hundreds of examples, this book demonstrates how to develop various kinds of applications--including those that work with databases--and web services. Learning Visual Basic .NET will help you build a solid foundation in .NET.
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International Nuclear Information System (INIS)
Miguel, Lucas de Castro
2017-01-01
In the last few decades, several studies have been conducted regarding the effectiveness of the use of virtual reality as a teaching tool. New and complex IT tools (Information and Communication Technologies) have also been developed. One such tool, is the Virtual Learning Environment (VLE). VLEs are internet media that use cyberspace to convey didactic content and can complement the orthodox teaching method, allowing students a new way of understanding complex content through digital interaction. This work aims to teach the operation of the first and second cycles of a pressurized water nuclear reactor through the development and use of a VLE. The VLE will use interactive virtual reality to demonstrate to the student the 'anatomy' of a generating nuclear power plant. There are several possibilities for future work using this VLE. One is the use as a data repository and 'virtual exhibition room' of each component of the nuclear reactor that researchers are modelling and developing. With these virtual objects allocated in a category, teachers could use this VLE in the classroom as a teaching tool while researchers could use the platform as a quick and practical way of viewing their online work and sharing it with other researchers. Thus, this VLE will be an effective tool for spreading knowledge of nuclear power more easily within, as well as outside of the research community. (author)
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Cloud Communities and Travel Diaries. Virtual Representations of Tourist Areas
Directory of Open Access Journals (Sweden)
Marco Platania
2014-06-01
Full Text Available Collective construction of descriptions can radically change the image of an area. This uncontrollable process is destined to become one of the main priority research areas also in tourism studies. The spread of Web sites in which telling stories and descriptions of territories has become a significant element in the network society, and the growing use of social networks and cloud communities, often in planning tourism, contributes to social description of touristic landscapes and influence the collective imaginary. In social space, territories are the result of the superposition of different layers, from the real one to the virtual, bound to a constant exchange of information. This phenomenon that could guide tourist attraction, begins to affect the choices of local institutions and residents.The aim of the paper is to give an interpretation on the construction of collective representation, which takes place, after the journey, through the on-line publication of a diary. The research is divided into two parts. In the first, we explain some theoretical aspects related to the representation of the travel, the sharing of information in virtual form and the construction of an imaginary touristic. Subsequently, are taken into account the results obtained in previous studies related to the analysis of the narratives of tourism experiences, shared within virtual spaces freely accessible on the net. These results will be used to develop a model of interpretation on the virtual representation of tourist areas.
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Briët, Olivier J T; Yukich, Joshua O; Pfeiffer, Constanze; Miller, William; Jaeger, Mulako S; Khanna, Nitin; Oppong, Samuel; Nardini, Peter; Ahorlu, Collins K; Keating, Joseph
2017-01-03
Long-lasting insecticidal nets (LLINs) are ineffective malaria transmission prevention tools if they are unused. Discomfort due to heat is the most commonly reported reason for not using nets, but this problem is largely unaddressed. With increasing rural electrification and the dropping price of solar power, fans could improve comfort inside nets and be affordable to populations in malaria endemic areas. Here, results are presented from a pilot randomized controlled cross-over study testing the effect of fans on LLIN use. Eighty-three households from two rural communities in Greater Accra, Ghana, randomized into three groups, participated in a 10-month cross-over trial. After a screening survey to identify eligible households, all households received new LLINs. Bͻkͻͻ net fan systems (one fan per member) were given to households in Group 1 and water filters were given to households in Group 2. At mid-point, Group 1 and 2 crossed over interventions. Households in Group 1 and 2 participated in fortnightly surveys on households' practices related to nets, fans and water filters, while households in Group 3 were surveyed only at screening, mid-point and study end. Entomological and weather data were collected throughout the study. Analysis took both 'per protocol' (PP) and 'intention to treat' (ITT) approaches. The mid- and end-point survey data from Group 1 and 2 were analysed using Firth logistic regressions. Fortnightly survey data from all groups were analysed using logistic regressions with random effects. Provision of fans to households appeared to increase net use in this study. Although the increase in net use explained by fans was not significant in the primary analyses (ITT odds ratio 3.24, p > 0.01; PP odds ratio = 1.17, p > 0.01), it was significant in secondary PP analysis (odds ratio = 1.95, p Fan use was 90-100% depending on the fortnightly visit. This pilot study could not provide definitive evidence that fans increase net use. A larger
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Combination of Assessment Indicators for Policy Support on Water Scarcity and Pollution Mitigation
Directory of Open Access Journals (Sweden)
Wei Yang
2016-05-01
Full Text Available Given increasing concern about seeking solutions to water scarcity and pollution (WSP, this paper is intent on developing significant assessment indicators as decision variables for providing reference for policy proposals on the mitigation of WSP. An indicator package consisting of footprints of freshwater consumption (FC and water pollutant discharge (WPD, virtual contents of freshwater and water pollutants, and inter-sectoral linkages in terms of industrial production, FC and WPD has been newly set up based on an extended input-output model. These indicators allow to provide specific and well-structured analysis on FC, WPD and the economy as well as their implicated interrelationships. The Source Region of Liao River located in northeastern China was selected as an empirical study area to apply the indicator package. The results indicate that farming and production of electricity industries are major contributors to FC; farming and breeding industries, and households are major contributors to WPD. The study area exports a large amount of net virtual total nitrogen, total phosphorus and chemical oxygen demand (29.01 × 103 t, 4.66 × 103 t, 60.38 × 103 t, respectively. Farming and breeding industries are the sectors whose production could be constrained to contribute to mitigating WSP without excessive negative impacts on the economy. Two categories of policies have been proposed to mitigate WSP based on the analysis of the indicator package. One is to introduce direct water pollutant treatment and water-saving policies to the target sectors; the other is to adjust industrial structure. The integrated indicator package developed and the methodology presented are expected to provide policy researchers and decision makers with references for more sound water management.
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Spring and surface water quality of the Cyprus ophiolites
Directory of Open Access Journals (Sweden)
C. Neal
2002-01-01
Full Text Available A survey of surface, spring and borehole waters associated with the ophiolite rocks of Cyprus shows five broad water types (1 Mg-HCO3, (2 Na-SO4-Cl-HCO3, (3 Na-Ca-Cl-SO4-OH-CO3, (4 Na-Cl-SO4 and (5 Ca-SO4. The waters represent a progression in chemical reactivity from surface waters that evolve within a groundwater setting due to hydrolysis of the basic/ultrabasic rock as modified by CO2-weathering. An increase in salinity is also observed which is due to mixing with a saline end-member (modified sea-water and dissolution of gypsum/anhydrite. In some cases, the waters have pH values greater than 11. Such high values are associated with low temperature serpentinisation reactions. The system is a net sink for CO2. This feature is related not only to the hydrolysis of the primary minerals in the rock, but also to CaCO3 or Ca-Mg-CO3 solubility controls. Under hyperalkaline conditions, virtually all the carbon dioxide is lost from the water due to the sufficiently high calcium levels and carbonate buffering is then insignificant. Calcium sulphate solubility controls may also be operative when calcium and sulphate concentrations are particularly high. Keywords: Cyprus, Troodos, ophiolite, serpentinisation, spring, stream, water quality, bromide, iodine, boron, trace elements, hyperalkaline.
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Pro-Nets versus No-Nets: Differences in Urban Older Adults' Predilections for Internet Use
Cresci, M. Kay; Yarandi, Hossein N.; Morrell, Roger W.
2010-01-01
Enthusiasm for information technology (IT) is growing among older adults. Many older adults enjoy IT and the Internet (Pro-Nets), but others have no desire to use it (No-Nets). This study found that Pro-Nets and No-Nets were different on a number of variables that might predict IT use. No-Nets were older, had less education and income, were…
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Sanchez-Murillo, R.; Brooks, E. S.; Boll, J.
2010-12-01
Discharge of waste water treatment plants (WWTPs) typically is viewed to result in water quality impairment. However, WWTPs can also be a source of nutrients to enhance the salmonid food web as well as an efficient way to maintain acceptable water temperature regimes and flow conditions during summer. We observed this paradox in West Fork Little Bear Creek (WFLB) in the City of Troy, Idaho. Despite the nutrient load, the WFLB had the highest Steelhead trout density in the watershed, with a mean density of 13.2 fish/100 m2. The objective of this project was to utilize a water quality model, QUAL2kw, and an ecology assessment to examine how the nutrient load from the WWTP affects: a) habitat conditions for steelhead juveniles, and b) physic-chemical parameters. Four monitoring stations were installed from May through November in 2009 and 2010. An undisturbed creek was used as a control site in 2010. Dissolved oxygen (DO), electrical conductivity, temperature, and discharge were measured continuously at each monitoring station. Weekly samples were collected at each monitoring station and analyzed for nitrate, nitrite, ammonia, total Kjeldahl nitrogen, total phosphorous, and orthophosphates. In 2010, Chlorophyll a was analyzed weekly, while bottom algae biomass was determined monthly. Results show that during summer months, the WWTP provides the majority of the flow (0.1 cfs) in the creek. Water samples and DO measurements taken 200 m downstream of the plant during late summer months indicate that nitrification process leads to low DO level well below the state standard of 6 mg/L for cold water biota. However dissolved oxygen levels recover within 1 km downstream. Discharge data suggest that without the flow from the treatment most of the creek would dry during late summer months. Abundance of macroinverbrates, high primary productivity, and sustained flow during summer suggests that the effluent from the WWTP is a net benefit to the Steelhead habitat in the basin
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Experiments and simulation of a net closing mechanism for tether-net capture of space debris
Sharf, Inna; Thomsen, Benjamin; Botta, Eleonora M.; Misra, Arun K.
2017-10-01
This research addresses the design and testing of a debris containment system for use in a tether-net approach to space debris removal. The tether-net active debris removal involves the ejection of a net from a spacecraft by applying impulses to masses on the net, subsequent expansion of the net, the envelopment and capture of the debris target, and the de-orbiting of the debris via a tether to the chaser spacecraft. To ensure a debris removal mission's success, it is important that the debris be successfully captured and then, secured within the net. To this end, we present a concept for a net closing mechanism, which we believe will permit consistently successful debris capture via a simple and unobtrusive design. This net closing system functions by extending the main tether connecting the chaser spacecraft and the net vertex to the perimeter and around the perimeter of the net, allowing the tether to actuate closure of the net in a manner similar to a cinch cord. A particular embodiment of the design in a laboratory test-bed is described: the test-bed itself is comprised of a scaled-down tether-net, a supporting frame and a mock-up debris. Experiments conducted with the facility demonstrate the practicality of the net closing system. A model of the net closure concept has been integrated into the previously developed dynamics simulator of the chaser/tether-net/debris system. Simulations under tether tensioning conditions demonstrate the effectiveness of the closure concept for debris containment, in the gravity-free environment of space, for a realistic debris target. The on-ground experimental test-bed is also used to showcase its utility for validating the dynamics simulation of the net deployment, and a full-scale automated setup would make possible a range of validation studies of other aspects of a tether-net debris capture mission.
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Trends and Consumption Structures of China’s Blue and Grey Water Footprint
Directory of Open Access Journals (Sweden)
Huixiao Wang
2018-04-01
Full Text Available Water footprint has become a common method to study the water resources utilization in recent years. By using input–output analysis and dilution theory, the internal water footprint, blue water footprint and grey water footprint of China from 2002 to 2012 were estimated, and the consumption structure of water footprint and virtual water trade were analyzed. The results show: (1 From 2002 to 2012, the average annual internal water footprint was 3.83 trillion m3 in China, of which the blue water footprint was 0.25 trillion m3, and the grey water footprint was 3.58 trillion m3 (with Grade III water standard accounting; both the internal water footprint and grey water footprint experienced decreasing trends from 2002 to 2012, except for a dramatic increase in 2010; (2 Average annual virtual blue water footprint was the greatest in agriculture (39.2%, while tertiary industry (27.5% and food and tobacco processing (23.7% were the top two highest for average annual virtual grey water footprint; (3 Virtual blue water footprint in most sectors showed increasing trends due to the increase of final demand, while virtual grey water footprint in most sectors showed decreasing trends due to the decreases of total return water coefficients and conversion coefficients of virtual grey water footprint; (4 For water resources, China was self-reliant: the water used for producing the products and services to meet domestic consumption was taken domestically; meanwhile, China exported virtual water to other countries, which aggravated the water stress in China.
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Swancar, Amy; Lee, T.M.; O'Hare, T. M.
2000-01-01
Lake Starr, a 134-acre seepage lake of multiple-sinkhole origin on the Lake Wales Ridge of central Florida, was the subject of a detailed water-budget study from August 1996 through July 1998. The study monitored the effects of hydrogeologic setting, climate, and ground-water pumping on the water budget and lake stage. The hydrogeologic setting of the Lake Starr basin differs markedly on the two sides of the lake. Ground water from the surficial aquifer system flows into the lake from the northwest side of the basin, and lake water leaks out to the surficial aquifer system on the southeast side of the basin. Lake Starr and the surrounding surficial aquifer system recharge the underlying Upper Floridan aquifer. The rate of recharge to the Upper Floridan aquifer is determined by the integrity of the intermediate confining unit and by the downward head gradient between the two aquifers. On the inflow side of the lake, the intermediate confining unit is more continuous, allowing ground water from the surficial aquifer system to flow laterally into the lake. Beneath the lake and on the southeast side of the basin, breaches in the intermediate confining unit enhance downward flow to the Upper Floridan aquifer, so that water flows both downward and laterally away from the lake through the ground-water flow system in these areas. An accurate water budget, including evaporation measured by the energy-budget method, was used to calculate net ground-water flow to the lake, and to do a preliminary analysis of the relation of net ground-water fluxes to other variables. Water budgets constructed over different timeframes provided insight on processes that affect ground-water interactions with Lake Starr. Weekly estimates of net ground-water flow provided evidence for the occurrence of transient inflows from the nearshore basin, as well as the short-term effects of head in the Upper Floridan aquifer on ground-water exchange with the lake. Monthly water budgets showed the effects
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Virtual Team Governance: Addressing the Governance Mechanisms and Virtual Team Performance
Zhan, Yihong; Bai, Yu; Liu, Ziheng
As technology has improved and collaborative software has been developed, virtual teams with geographically dispersed members spread across diverse physical locations have become increasingly prominent. Virtual team is supported by advancing communication technologies, which makes virtual teams able to largely transcend time and space. Virtual teams have changed the corporate landscape, which are more complex and dynamic than traditional teams since the members of virtual teams are spread on diverse geographical locations and their roles in the virtual team are different. Therefore, how to realize good governance of virtual team and arrive at good virtual team performance is becoming critical and challenging. Good virtual team governance is essential for a high-performance virtual team. This paper explores the performance and the governance mechanism of virtual team. It establishes a model to explain the relationship between the performance and the governance mechanisms in virtual teams. This paper is focusing on managing virtual teams. It aims to find the strategies to help business organizations to improve the performance of their virtual teams and arrive at the objectives of good virtual team management.
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Munir, T. M.; Perkins, M.; Kaing, E.; Strack, M.
2015-02-01
Midlatitude treed bogs represent significant carbon (C) stocks and are highly sensitive to global climate change. In a dry continental treed bog, we compared three sites: control, recent (1-3 years; experimental) and older drained (10-13 years), with water levels at 38, 74 and 120 cm below the surface, respectively. At each site we measured carbon dioxide (CO2) fluxes and estimated tree root respiration (Rr; across hummock-hollow microtopography of the forest floor) and net primary production (NPP) of trees during the growing seasons (May to October) of 2011-2013. The CO2-C balance was calculated by adding the net CO2 exchange of the forest floor (NEff-Rr) to the NPP of the trees. From cooler and wetter 2011 to the driest and the warmest 2013, the control site was a CO2-C sink of 92, 70 and 76 g m-2, the experimental site was a CO2-C source of 14, 57 and 135 g m-2, and the drained site was a progressively smaller source of 26, 23 and 13 g CO2-C m-2. The short-term drainage at the experimental site resulted in small changes in vegetation coverage and large net CO2 emissions at the microforms. In contrast, the longer-term drainage and deeper water level at the drained site resulted in the replacement of mosses with vascular plants (shrubs) on the hummocks and lichen in the hollows leading to the highest CO2 uptake at the drained hummocks and significant losses in the hollows. The tree NPP (including above- and below-ground growth and litter fall) in 2011 and 2012 was significantly higher at the drained site (92 and 83 g C m-2) than at the experimental (58 and 55 g C m-2) and control (52 and 46 g C m-2) sites. We also quantified the impact of climatic warming at all water table treatments by equipping additional plots with open-top chambers (OTCs) that caused a passive warming on average of ~ 1 °C and differential air warming of ~ 6 °C at midday full sun over the study years. Warming significantly enhanced shrub growth and the CO2 sink function of the drained
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Assessing the engineering performance of affordable net-zero energy housing
Wallpe, Jordan P.
The purpose of this research was to evaluate affordable technologies that are capable of providing attractive, cost-effective energy savings to the housing industry. The research did so by investigating the 2011 Solar Decathlon competition, with additional insight from the Purdue INhome. Insight from the Purdue INhome verified the importance of using a three step design process to design a net-zero energy building. In addition, energy consumption values of the INhome were used to compare and contrast different systems used in other houses. Evaluation of unbiased competition contests gave a better understanding of how a house can realistically reach net-zero. Upon comparison, off-the-shelf engineering systems such as super-efficient HVAC units, heat pump hot water heaters, and properly designed photovoltaic arrays can affordably enable a house to become net-zero. These important and applicable technologies realized from the Solar Decathlon will reduce the 22 percent of all energy consumed through the residential sector in the United States. In conclusion, affordable net-zero energy buildings can be built today with commitment from design professionals, manufacturers, and home owners.
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Prospects of the aqueous self-cooled blanket concept for NET
International Nuclear Information System (INIS)
Snykers, M.; Bruggeman, A.; Bogaerts, W.F.; Embrechts, M.J.; Steiner, D.; Daenner, W.
1989-01-01
A low-technology Aqueous Self-Cooled Blanket (ASCB) concept has been proposed for the Next European Torus (NET). This concept relies on structural material and cooling water, with small amounts of lithium compounds for tritium production. Following preliminary investigations, LiOH, LiNO 3 , LiNO 2 and Li 2 SO 4 are currently under consideration as tritium breeding materials in solution. The concept may benefit from the proven technologies from the PWRs and from the CANDU tritium extraction systems. It combines good shielding and breeding capabilities. It would serve as a reliable environment for experimenting with several DEMOnstration reactor-relevant blanket modules in NET. Since net tritium breeding is not a design requirement for NET, sufficient tritium breeding can be obtained without the application of external neutron multipliers if enrichment in 6 Li is utilized. For a DEMOnstration reactor ASCB-based blanket, neutron multipliers have to be incorporated and temperature and pressure have to be increased. Radiolysis and corrosion aspects are of particular concern and need further investigation. (orig.)
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Nutrient fluxes and net metabolism in a coastal lagoon SW peninsula of Baja California, Mexico
Directory of Open Access Journals (Sweden)
Cervantes Duarte, R.
2016-09-01
Full Text Available Fluxes of nutrients and net metabolism were estimated in coastal lagoon Magdalena Bay using LOICZ biogeochemical model. In situ data were obtained from 14 sites in the lagoon and also from a fixed site in the adjacent ocean area. Intense upwelling (February to July and faint upwelling (August to January were analyzed from monthly time series. The Temperature, nitrite + nitrate, ammonium and phosphate within the lagoon showed significant differences (p<0.05 between the two periods. Salinity (p=0.408 was more homogeneous (no significantly different due to mixing processes. During the intense upwelling period, nutrients increased in and out of the lagoon due to the influence of Transitional Water and Subartic Water transported by the California Current. However, during the faint upwelling, from August to January, the Transition Water and Subtropical Surface Water were predominant. Magdalena Bay showed denitrification processes of throughout the year as it occurred in other semi-arid coastal lagoons. It also showed a net autotrophic metabolism during intense upwelling and heterotrophic metabolism during faint upwelling. Understanding nutrient flows and net metabolism through simple biogeochemical models can provide tools for better management of the coastal zone.
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Server consolidation for heterogeneous computer clusters using Colored Petri Nets and CPN Tools
Directory of Open Access Journals (Sweden)
Issam Al-Azzoni
2015-10-01
Full Text Available In this paper, we present a new approach to server consolidation in heterogeneous computer clusters using Colored Petri Nets (CPNs. Server consolidation aims to reduce energy costs and improve resource utilization by reducing the number of servers necessary to run the existing virtual machines in the cluster. It exploits the emerging technology of live migration which allows migrating virtual machines between servers without stopping their provided services. Server consolidation approaches attempt to find migration plans that aim to minimize the necessary size of the cluster. Our approach finds plans which not only minimize the overall number of used servers, but also minimize the total data migration overhead. The latter objective is not taken into consideration by other approaches and heuristics. We explore the use of CPN Tools in analyzing the state spaces of the CPNs. Since the state space of the CPN model can grow exponentially with the size of the cluster, we examine different techniques to generate and analyze the state space in order to find good plans to server consolidation within acceptable time and computing power.
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ROOT.NET: Using ROOT from .NET languages like C# and F#
Watts, G.
2012-12-01
ROOT.NET provides an interface between Microsoft's Common Language Runtime (CLR) and .NET technology and the ubiquitous particle physics analysis tool, ROOT. ROOT.NET automatically generates a series of efficient wrappers around the ROOT API. Unlike pyROOT, these wrappers are statically typed and so are highly efficient as compared to the Python wrappers. The connection to .NET means that one gains access to the full series of languages developed for the CLR including functional languages like F# (based on OCaml). Many features that make ROOT objects work well in the .NET world are added (properties, IEnumerable interface, LINQ compatibility, etc.). Dynamic languages based on the CLR can be used as well, of course (Python, for example). Additionally it is now possible to access ROOT objects that are unknown to the translation tool. This poster will describe the techniques used to effect this translation, along with performance comparisons, and examples. All described source code is posted on the open source site CodePlex.
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ROOT.NET: Using ROOT from .NET languages like C and F
International Nuclear Information System (INIS)
Watts, G
2012-01-01
ROOT.NET provides an interface between Microsoft's Common Language Runtime (CLR) and .NET technology and the ubiquitous particle physics analysis tool, ROOT. ROOT.NET automatically generates a series of efficient wrappers around the ROOT API. Unlike pyROOT, these wrappers are statically typed and so are highly efficient as compared to the Python wrappers. The connection to .NET means that one gains access to the full series of languages developed for the CLR including functional languages like F (based on OCaml). Many features that make ROOT objects work well in the .NET world are added (properties, IEnumerable interface, LINQ compatibility, etc.). Dynamic languages based on the CLR can be used as well, of course (Python, for example). Additionally it is now possible to access ROOT objects that are unknown to the translation tool. This poster will describe the techniques used to effect this translation, along with performance comparisons, and examples. All described source code is posted on the open source site CodePlex.
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Innovative application of virtual display technique in virtual museum
Zhang, Jiankang
2017-09-01
Virtual museum refers to display and simulate the functions of real museum on the Internet in the form of 3 Dimensions virtual reality by applying interactive programs. Based on Virtual Reality Modeling Language, virtual museum building and its effective interaction with the offline museum lie in making full use of 3 Dimensions panorama technique, virtual reality technique and augmented reality technique, and innovatively taking advantages of dynamic environment modeling technique, real-time 3 Dimensions graphics generating technique, system integration technique and other key virtual reality techniques to make sure the overall design of virtual museum.3 Dimensions panorama technique, also known as panoramic photography or virtual reality, is a technique based on static images of the reality. Virtual reality technique is a kind of computer simulation system which can create and experience the interactive 3 Dimensions dynamic visual world. Augmented reality, also known as mixed reality, is a technique which simulates and mixes the information (visual, sound, taste, touch, etc.) that is difficult for human to experience in reality. These technologies make virtual museum come true. It will not only bring better experience and convenience to the public, but also be conducive to improve the influence and cultural functions of the real museum.
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FishNet: an online database of zebrafish anatomy
Directory of Open Access Journals (Sweden)
Gibson Abigail J
2007-08-01
Full Text Available Abstract Background Over the last two decades, zebrafish have been established as a genetically versatile model system for investigating many different aspects of vertebrate developmental biology. With the credentials of zebrafish as a developmental model now well recognized, the emerging new opportunity is the wider application of zebrafish biology to aspects of human disease modelling. This rapidly increasing use of zebrafish as a model for human disease has necessarily generated interest in the anatomy of later developmental phases such as the larval, juvenile, and adult stages, during which many of the key aspects of organ morphogenesis and maturation take place. Anatomical resources and references that encompass these stages are non-existent in zebrafish and there is therefore an urgent need to understand how different organ systems and anatomical structures develop throughout the life of the fish. Results To overcome this deficit we have utilized the technique of optical projection tomography to produce three-dimensional (3D models of larval fish. In order to view and display these models we have created FishNet http://www.fishnet.org.au, an interactive reference of zebrafish anatomy spanning the range of zebrafish development from 24 h until adulthood. Conclusion FishNet contains more than 36 000 images of larval zebrafish, with more than 1 500 of these being annotated. The 3D models can be manipulated on screen or virtually sectioned. This resource represents the first complete embryo to adult atlas for any species in 3D.
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IMPACT OF HEAVY METAL TO FISH AQUACULTURE IN FLOATING NET CAGE IN CIRATA RESERVOIR, INDONESIA
Directory of Open Access Journals (Sweden)
Tri Heru Prihadi
2008-06-01
Full Text Available Utilization of Cirata Reservoir for fisheries aquaculture with floating net cage system has been increasing rapidly. Industrial waste existed along watershed brings significant heavy metal pollutant that flows and difficult to control. Consequences of such activities were reflected in the degradation of reservoir environment indicated by sedimentation, water quality degradation and fish mass mortality because of up welling. The objectives of this research were: 1 to obtain data and information on heavy metal content in Cirata Reservoir waters, and 2 to observe and understand the effect of heavy metal to the fish cultured in floating net cage to support aquaculture in floating net cage system. Water quality and fish histology analyses were the methodologies used in this research. Descriptive and laboratory analysis were carry out to analysis the data. Based on observation and descriptive analyses, the content of heavy metal in Cirata Reservoir was classified as worse. Concentration of Pb, Cr, Hg, and Cd in the sample of water and tilapia digestive organ becomes fragile. Infiltration of hemoglobin cell, necrosis, degeneration and pigmentation occurred in body organs when up welling happened. Beside that, during up-welling digestive organ become easily breakable resulted in fish mass mortality in floating net cage. The affinity of hemoglobin to the toxic gas was higher than to oxygen, therefore aeration was not affective and mass mortality cannot be avoided. This was because of various events that occured to the fish and the other water biota that encompassed regular diffusion, bio-magnification, and bio-concentration to fish.
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Virtual modeling of robot-assisted manipulations in abdominal surgery.
Berelavichus, Stanislav V; Karmazanovsky, Grigory G; Shirokov, Vadim S; Kubyshkin, Valeriy A; Kriger, Andrey G; Kondratyev, Evgeny V; Zakharova, Olga P
2012-06-27
To determine the effectiveness of using multidetector computed tomography (MDCT) data in preoperative planning of robot-assisted surgery. Fourteen patients indicated for surgery underwent MDCT using 64 and 256-slice MDCT. Before the examination, a specially constructed navigation net was placed on the patient's anterior abdominal wall. Processing of MDCT data was performed on a Brilliance Workspace 4 (Philips). Virtual vectors that imitate robotic and assistant ports were placed on the anterior abdominal wall of the 3D model of the patient, considering the individual anatomy of the patient and the technical capabilities of robotic arms. Sites for location of the ports were directed by projection on the roentgen-positive tags of the navigation net. There were no complications observed during surgery or in the post-operative period. We were able to reduce robotic arm interference during surgery. The surgical area was optimal for robotic and assistant manipulators without any need for reinstallation of the trocars. This method allows modeling of the main steps in robot-assisted intervention, optimizing operation of the manipulator and lowering the risk of injuries to internal organs.
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Realistic Visualization of Virtual Views and Virtual Cinema
DEFF Research Database (Denmark)
Livatino, Salvatore
2005-01-01
Realistic Virtual View Visualization is a new field of research which has received increasing attention in recent years. It is strictly related to the increased popularity of virtual reality and the spread of its applications, among which virtual photography and cinematography. The use of computer...... generated characters, "virtual actors", in the motion picture production increases every day. While the most known computer graphics techniques have largely been adopted successfully in nowadays fictions, it still remains very challenging to implement virtual actors which would resemble, visually, human...... beings. Interestingly, film directors have been looking at the recent progress achieved by the research community in the field of realistic visualization of virtual views, and they have successfully implemented state of the art research approaches in their productions. An innovative concept...
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Application of a virtual watershed in academic education
Directory of Open Access Journals (Sweden)
A. L. Horn
2005-01-01
Full Text Available Hydrologic models of watersheds often represent complex systems which are difficult to understand regarding to their structure and dynamics. Virtual watersheds, i.e. watersheds which exist only in the virtual reality of a computer system, are an approach to simplify access to this real-world complexity. In this study we present the virtual watershed KIELSHED-1, a 117 km2 v-shaped valley with grassland on a "Cambisol" soil type. Two weather scenarios are delivered with the watershed: a simplified artificial weather scenario based on long-term data of a German weather station as well as an unmodified data record. The input data and parameters are compiled according to the conventions of the SWAT 2000 hydrological model. KIELSHED-1 is mainly used for education, and illustrative application examples, i.e. calculation of water balance, model calibration, development of land use scenarios, give an insight to the capabilities of the virtual watershed.
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Virtual Satellite Construction and Application for Image Classification
International Nuclear Information System (INIS)
Su, W G; Su, F Z; Zhou, C H
2014-01-01
Nowadays, most remote sensing image classification uses single satellite remote sensing data, so the number of bands and band spectral width is consistent. In addition, observed phenomenon such as land cover have the same spectral signature, which causes the classification accuracy to decrease as different data have unique characteristic. Therefore, this paper analyzes different optical remote sensing satellites, comparing the spectral differences and proposes the ideas and methods to build a virtual satellite. This article illustrates the research on the TM, HJ-1 and MODIS data. We obtained the virtual band X 0 through these satellites' bands combined it with the 4 bands of a TM image to build a virtual satellite with five bands. Based on this, we used these data for image classification. The experimental results showed that the virtual satellite classification results of building land and water information were superior to the HJ-1 and TM data respectively
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Virtual Trondheim: A Virtual Environment for Tourism and Education
Jose, Dawn Alphonse
2015-01-01
The purpose of this study is to investigate whether educational activities in tourism can be supported by virtual reality technologies, using virtual world frameworks. Settings of virtual world of SecondLife and a recent Virtual Reality technology known as Oculus Rift were used in the thesis work with the city of Trondheim as the main context. Theoretical studies on Virtual Reality systems were conducted and data for the research were obtained through empirical studies condu...
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Petri nets and fault diagnosis in nuclear reactors
International Nuclear Information System (INIS)
Jalel, N.A.; Nicholson, H.
1990-11-01
The possibility of applying Petri nets (Pns) as a modelling tool to represent any fault or accident that might occur in the Loss Of Fluid Test (LOFT) reactor, small scale pressurised water reactor, is discussed and analysed. Pns are developed to assist the nuclear reactor operator in identifying any fault or alarm that might arise in the power station. (author)
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DEFF Research Database (Denmark)
Henriksen, Knud; Sporring, Jon; Hornbæk, Kasper
2004-01-01
reviews and provides a mathematical foundation for virtual trackballs. The first, but still popular, virtual trackball was described by Chen et al. [CHECK END OF SENTENCE]. We show that the virtual trackball by Chen et al. does not rotate the object along the intended great circular arc on the virtual...... trackball and we give a correction. Another popular virtual trackball is Shoemake's quaternion implementation [CHECK END OF SENTENCE], which we show to be a special case of the virtual trackball by Chen et al.. Shoemake extends the scope of the virtual trackball to the full screen. Unfortunately, Shoemake......'s virtual trackball is inhomogeneous and discontinuous with consequences for usability. Finally, we review Bell's virtual trackball [CHECK END OF SENTENCE] and discuss studies of the usability of virtual trackballs....
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Pappas, Marjorie L.
2004-01-01
Virtual libraries are becoming more and more common. Most states have a virtual library. A growing number of public libraries have a virtual presence on the Web. Virtual libraries are a growing addition to school library media collections. The next logical step would be personal virtual libraries. A personal virtual library (PVL) is a collection…
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Energy Technology Data Exchange (ETDEWEB)
Miguel, Lucas de Castro
2017-07-01
In the last few decades, several studies have been conducted regarding the effectiveness of the use of virtual reality as a teaching tool. New and complex IT tools (Information and Communication Technologies) have also been developed. One such tool, is the Virtual Learning Environment (VLE). VLEs are internet media that use cyberspace to convey didactic content and can complement the orthodox teaching method, allowing students a new way of understanding complex content through digital interaction. This work aims to teach the operation of the first and second cycles of a pressurized water nuclear reactor through the development and use of a VLE. The VLE will use interactive virtual reality to demonstrate to the student the 'anatomy' of a generating nuclear power plant. There are several possibilities for future work using this VLE. One is the use as a data repository and 'virtual exhibition room' of each component of the nuclear reactor that researchers are modelling and developing. With these virtual objects allocated in a category, teachers could use this VLE in the classroom as a teaching tool while researchers could use the platform as a quick and practical way of viewing their online work and sharing it with other researchers. Thus, this VLE will be an effective tool for spreading knowledge of nuclear power more easily within, as well as outside of the research community. (author)
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Wen, Heming; Le-Ngoc, Tho
2013-01-01
This SpringerBriefs is an overview of the emerging field of wireless access and mobile network virtualization. It provides a clear and relevant picture of the current virtualization trends in wireless technologies by summarizing and comparing different architectures, techniques and technologies applicable to a future virtualized wireless network infrastructure. The readers are exposed to a short walkthrough of the future Internet initiative and network virtualization technologies in order to understand the potential role of wireless virtualization in the broader context of next-generation ubiq
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International Nuclear Information System (INIS)
Finkelstein, D.
1989-01-01
The quantum net unifies the basic principles of quantum theory and relativity in a quantum spacetime having no ultraviolet infinities, supporting the Dirac equation, and having the usual vacuum as a quantum condensation. A correspondence principle connects nets to Schwinger sources and further unifies the vertical structure of the theory, so that the functions of the many hierarchic levels of quantum field theory (predicate algebra, set theory, topology,hor-ellipsis, quantum dynamics) are served by one in quantum net dynamics
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DEFF Research Database (Denmark)
various journals and collections. As a result, much of this knowledge is not readily available to people who may be interested in using high-level nets. Within the Petri net community this problem has been discussed many times, and as an outcome this book has been compiled. The book contains reprints...... of some of the most important papers on the application and theory of high-level Petri nets. In this way it makes the relevant literature more available. It is our hope that the book will be a useful source of information and that, e.g., it can be used in the organization of Petri net courses. To make......High-level Petri nets are now widely used in both theoretical analysis and practical modelling of concurrent systems. The main reason for the success of this class of net models is that they make it possible to obtain much more succinct and manageable descriptions than can be obtained by means...
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Ruiz-Corbella, Marta; Álvarez-González, Beatriz
2014-01-01
Mobility of higher education students is one of the main indicators of competitiveness among universities, and a key aspect for quality in education. Colleges with virtual and distance methodologies include student mobility programmes. Within this context, the Active Projects (Erasmus MUNDUS Programme, EC: Net-Active and Active-Asia) compare and…
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Climatic Forecasting of Net Infiltration at Yucca Mountain Using Analogue Meteorological Data
International Nuclear Information System (INIS)
B. Faybishenko
2006-01-01
At Yucca Mountain, Nevada, future changes in climatic conditions will most likely alter net infiltration, or the drainage below the bottom of the evapotranspiration zone within the soil profile or flow across the interface between soil and the densely welded part of the Tiva Canyon Tuff. The objectives of this paper are to: (a) develop a semi-empirical model and forecast average net infiltration rates, using the limited meteorological data from analogue meteorological stations, for interglacial (present day), and future monsoon, glacial transition, and glacial climates over the Yucca Mountain region, and (b) corroborate the computed net-infiltration rates by comparing them with the empirically and numerically determined groundwater recharge and percolation rates through the unsaturated zone from published data. In this paper, the author presents an approach for calculations of net infiltration, aridity, and precipitation-effectiveness indices, using a modified Budyko's water-balance model, with reference-surface potential evapotranspiration determined from the radiation-based Penman (1948) formula. Results of calculations show that net infiltration rates are expected to generally increase from the present-day climate to monsoon climate, to glacial transition climate, and then to the glacial climate. The forecasting results indicate the overlap between the ranges of net infiltration for different climates. For example, the mean glacial net-infiltration rate corresponds to the upper-bound glacial transition net infiltration, and the lower-bound glacial net infiltration corresponds to the glacial transition mean net infiltration. Forecasting of net infiltration for different climate states is subject to numerous uncertainties-associated with selecting climate analogue sites, using relatively short analogue meteorological records, neglecting the effects of vegetation and surface runoff and runon on a local scale, as well as possible anthropogenic climate changes
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Liquid metal cooled blanket concept for NET
International Nuclear Information System (INIS)
Malang, S.; Casal, V.; Arheidt, K.; Fischer, U.; Link, W.; Rust, K.
1986-01-01
A blanket concept for NET using liquid lithium-lead both as breeder material and as coolant is described. The need for inboard breeding is avoided by using beryllium as neutron multiplier in the outboard blanket. Novel flow channel inserts are employed in all poloidal ducts to reduce the MHD pressure drop. The concept offers a simple mechanical design and a higher tritium breeding ratio compared to water- and gas-cooled blankets. (author)
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Colonoscopy - virtual; CT colonography; Computed tomographic colonography; Colography - virtual ... Differences between virtual and conventional colonoscopy include: VC can view the colon from many different angles. This is not as easy ...
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Gomez, Margarita Victoria
2009-01-01
The objective of this work is a reflection on the ethics of education on the net as a contribution to the face-to-face interaction in the virtual world. We think the ethics is a result of a process of responsible interchange with others. Two important thinkers of the last few decades, Emmanuel Levinas e Paulo Freire contribute each one with one's…
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DEFF Research Database (Denmark)
Jensen, Sisse Siggaard
2006-01-01
-systems, the paper introduces the designing strategy referred to as virtual exploratories. Some of the advanced virtual worlds may inspire the design of such provoking and challenging virtual exploratories, and especially the Massively Multi-User Online Role-Playing Games (MMORPGS). However, if we have to learn from...... the design and activity of the advanced virtual worlds and role-playing games, then the empirical research on the actors’ activity, while they are acting, is an important precondition to it. A step towards the conception of such a designing strategy for virtual exploratories is currently pursued....... [1] The research project: Actors and Avatars Communicating in Virtual Worlds – an Empirical Analysis of Actors’ Sense-making Strategies When Based on a Communication Theoretical Approach’ (2006-2007) is supported...
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The virtual mass of a growing and collapsing bubble
International Nuclear Information System (INIS)
Abdullah Abbas Kendoush
2005-01-01
Full text of publication follows: The acceleration of bubbles are encountered in flash evaporation, that results form the hypothetical sudden depressurization of the primary cooling circuit of light water nuclear reactors. Bubble growth during flash evaporation is a transient phenomenon, leads to a virtual mass force that should be introduced into the equation of motion. The importance of the virtual mass concept was appreciated by many investigators. They demonstrated that the inclusion of the virtual mass effect into the numerical solution of the transient two-phase flow appears to improve numerical stability and efficiency, and to achieve accurate results in many cases of practical concern. Analytical solutions were obtained for the virtual mass coefficient of a growing and collapsing bubble at high and low Jakob numbers. The method of solution was similar to that used previously by the author [Physics of Fluids 15(2782- 2785)2003]. The present solution is valid by its asymptotic approach to the limit of the virtual mass coefficient of the constant volume bubble. (author)
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Utilization of net energy analysis as a method of evaluating energy systems
International Nuclear Information System (INIS)
Lee, Gi Won; Cho, Joo Hyun; Hah, Yung Joon
1994-01-01
It can be said that the upturn of Korean nuclear power program started in early 70's while future plants for the construction of new nuclear power plants virtually came to a halt in United States since the late 70's. It is projected that power plant systems from combination of nuclear and coal fired types might shift to all coal fired type in U.S., considering the current U.S. trend of construction on the new plants. However, with the depletion of natural resources, it may be desirable to understand the utilization of two competitive utility technologies in terms of invested energy. Presented in this paper is a method of comparing two energy systems in terms of energy investment and a brief result from energy economic analysis of nuclear power plant and coal fired steam power plant to illustrate the methodology. The method of comparison is Net Energy Analysis (NEA). In doing so, Input-Output Analysis (lOA) among industries and commodities is done. Using these information, net energy ratios are calculated and compared. Although NEA does not offer conclusive solution, it can be used as a screening process in decision making
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PROBLEMS OF BIOFOULING ON FISH–CAGE NETS IN AQUACULTURE
Directory of Open Access Journals (Sweden)
Merica Slišković
2002-09-01
Full Text Available Biofouling on fish–cage netting is a serious technical and economical problem to aquaculture worldwide. Compensation for the effects of biofouling must be included in cage system design and planning, as fouling can dramatically increase both weight and drag. Settlements of sessile plants and animals, with accumulation of the detritus diminish the size of mesh and can rapidly occlude mesh. Negative effect of smaller mesh size is changing in water flow trough the cages. Biofouling problems necessitating purchase of a second sets of nets or more, and frequent cleaning and changing of biofouling. Changing and cleaning frequency depend on many factors such as: location of cages (near the coast or off shore, productivity of that location, time of the year, time period in which the cages are placed on that location (cause of loading of phosphorus and nitrogen from the unconsumed food in the sediment. Net changing and cleaning procedures are labor and capital intensive. Process of the cleaning of the nets is inadequate, especially when there isnžt adequate equipment available as it is case in smaller aquaculture industry. Chemical control of biofouling e. g. use of antifoulants is questioningly cause of their possible negative effects on breeding species and environment.
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International Nuclear Information System (INIS)
Carberry, M
1996-01-01
The paper is about the planning of nets in areas of low density like it is the case of the rural areas. The author includes economic and technological aspects, planning of nets, demands and management among others
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Assessment of food-water nexus by water footprint: a case study in Saskatchewan, Canada
Zhao, Y.; Si, B.
2016-12-01
It is important but challengeable to understand the water-food nexus complexity. The water footprint (WF), a relatively new index, is a comprehensive indicator that can be used to evaluate crop water production. This paper aims to 1) determine how water footprint changes at different crop rotational types; 2) investigate what is difference if WF is calculated by yield-based or protein-based; and 3) explore how virtual water flows are responding to regional meteorological, agricultural, and socio-economic factors. The result provided the water footprint and virtual water flow exemplified for Saskatchewan agri-food production industries. By using the water footprint, we determined the best rotation for pulse crops in terms of efficiency of water productivity and water-saving opportunity. While yield is a comprehensive index to assess the productivity (yield-based WF), it underestimated the contribution of some crops, such as pulse crops with relatively low yield but high protein contents (protein-based WF). Consequently, we concluded that water-saving benefits can be achieved by the development and adoption of water efficient technology and better virtual water flows may be achieved by increased area of low water footprint in Saskatchewan. Our finding improves the current concepts of water and food security, informs production and trade decisions, and thus suggests optimal strategies by reduced water footprints in terms of agricultural management.
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Ferrara, Alex
2007-01-01
Web services are poised to become a key technology for a wide range of Internet-enabled applications, spanning everything from straight B2B systems to mobile devices and proprietary in-house software. While there are several tools and platforms that can be used for building web services, developers are finding a powerful tool in Microsoft's .NET Framework and Visual Studio .NET. Designed from scratch to support the development of web services, the .NET Framework simplifies the process--programmers find that tasks that took an hour using the SOAP Toolkit take just minutes. Programming .NET
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Monitoring the englacial fracture state using virtual-reflector seismology
Lindner, F.; Weemstra, C.; Walter, F.; Hadziioannou, C.
2017-12-01
Fracturing and changes in the englacial macroscopic water content change the elastic bulk properties of ice bodies. Small seismic velocity variations, resulting from such changes, can be measured using a technique called coda-wave interferometry. Here, coda refers to the later-arriving, multiply scattered waves. Often, this technique is applied to so-called virtual-source responses, which can be obtained using seismic interferometry (a simple crosscorrelation process). Compared to other media (e.g., the Earth's crust), however, ice bodies exhibit relatively little scattering. This complicates the application of coda-wave interferometry to the retrieved virtual-source responses. In this work, we therefore investigate the applicability of coda-wave interferometry to virtual-source responses obtained using two alternative seismic interferometric techniques, namely, seismic interferometry by multidimensional deconvolution (SI by MDD), and virtual-reflector seismology (VRS). To that end, we use synthetic data, as well as active-source glacier data acquired on Glacier de la Plaine Morte, Switzerland. Both SI by MDD and VRS allow the retrieval of more accurate virtual-source responses. In particular, the dependence of the retrieved virtual-source responses on the illumination pattern is reduced. We find that this results in more accurate glacial phase-velocity estimates. In addition, VRS introduces virtual reflections from a receiver contour (partly) enclosing the medium of interest. By acting as a sort of virtual reverberation, the coda resulting from the application of VRS significantly increases seismic monitoring capabilities, in particular in cases where natural scattering coda is not available.
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Wang, Jingxian; Bernhöft, Silke; Pfister, Gerd; Schramm, Karl-Werner
2014-10-15
SPMD-based virtual organisms (VOs) were deployed at five to eight sites in the Three Gorges Reservoir (TGR), China for five periods in 2008, 2009 and 2011. The water exposure of aryl hydrocarbon receptor (AhR) agonists was assessed by the VOs. The chosen bioassay response for the extracts of the VOs, the induction of 7-ethoxyresorufin-O-deethylase (EROD) was assayed using a rat hepatoma cell line (H4IIE). The results show that the extracts from the VOs could induce AhR activity significantly, whereas the chemically derived 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) equivalent (TEQcal) accounted for water level reached a maximum of 175 m. Although the aqueous concentration of AhR agonists of 0.8-4.8 pg TCDDL(-1) in TGR was not alarming, the tendency of accumulating high concentration of AhR agonists in VO lipid and existence of possible synergism or antagonism in the water may exhibit a potential hazard to local biota being exposed to AhR agonists. Copyright © 2014 Elsevier B.V. All rights reserved.
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Lenselink, Eelke B; Beuming, Thijs; Sherman, Woody; van Vlijmen, Herman W T; IJzerman, Adriaan P
2014-06-23
A major challenge in structure-based virtual screening (VS) involves the treatment of explicit water molecules during docking in order to improve the enrichment of active compounds over decoys. Here we have investigated this in the context of the adenosine A2A receptor, where water molecules have previously been shown to be important for achieving high enrichment rates with docking, and where the positions of some binding site waters are known from a high-resolution crystal structure. The effect of these waters (both their presence and orientations) on VS enrichment was assessed using a carefully curated set of 299 high affinity A2A antagonists and 17,337 decoys. We show that including certain crystal waters greatly improves VS enrichment and that optimization of water hydrogen positions is needed in order to achieve the best results. We also show that waters derived from a molecular dynamics simulation - without any knowledge of crystallographic waters - can improve enrichments to a similar degree as the crystallographic waters, which makes this strategy applicable to structures without experimental knowledge of water positions. Finally, we used decision trees to select an ensemble of structures with different water molecule positions and orientations that outperforms any single structure with water molecules. The approach presented here is validated against independent test sets of A2A receptor antagonists and decoys from the literature. In general, this water optimization strategy could be applied to any target with waters-mediated protein-ligand interactions.
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Daugherty, Ana M; Yuan, Peng; Dahle, Cheryl L; Bender, Andrew R; Yang, Yiqin; Raz, Naftali
2015-09-01
Studies of human navigation in virtual maze environments have consistently linked advanced age with greater distance traveled between the start and the goal and longer duration of the search. Observations of search path geometry suggest that routes taken by older adults may be unnecessarily complex and that excessive path complexity may be an indicator of cognitive difficulties experienced by older navigators. In a sample of healthy adults, we quantify search path complexity in a virtual Morris water maze with a novel method based on fractal dimensionality. In a two-level hierarchical linear model, we estimated improvement in navigation performance across trials by a decline in route length, shortening of search time, and reduction in fractal dimensionality of the path. While replicating commonly reported age and sex differences in time and distance indices, a reduction in fractal dimension of the path accounted for improvement across trials, independent of age or sex. The volumes of brain regions associated with the establishment of cognitive maps (parahippocampal gyrus and hippocampus) were related to path dimensionality, but not to the total distance and time. Thus, fractal dimensionality of a navigational path may present a useful complementary method of quantifying performance in navigation. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
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Water Footprint of Cities: A Review and Suggestions for Future Research
Directory of Open Access Journals (Sweden)
Willa Paterson
2015-06-01
Full Text Available Cities are hotspots of commodity consumption, with implications for both local and systemic water resources. Water flows “virtually” into and out of cities through the extensive cross-boundary exchange of goods and services. Both virtual and real water flows are affected by water supply investments and urban planning decisions, which influence residential, commercial, and industrial development. This form of water “teleconnection” is being increasingly recognized as an important aspect of water decision-making. The role of trade and virtual water flows as an alternative to expanding a city’s “real” water supply is rarely acknowledged, with an emphasis placed instead on monotonic expansion of engineering potable water supplies. We perform a literature review of water footprint studies to evaluate the potential and importance of taking virtual flows into account in urban planning and policy. We compare and contrast current methods to assess virtual water flows. We also identify and discuss priorities for future research in urban water footprint analysis.
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Sensitivity-based virtual fields for the non-linear virtual fields method
Marek, Aleksander; Davis, Frances M.; Pierron, Fabrice
2017-09-01
The virtual fields method is an approach to inversely identify material parameters using full-field deformation data. In this manuscript, a new set of automatically-defined virtual fields for non-linear constitutive models has been proposed. These new sensitivity-based virtual fields reduce the influence of noise on the parameter identification. The sensitivity-based virtual fields were applied to a numerical example involving small strain plasticity; however, the general formulation derived for these virtual fields is applicable to any non-linear constitutive model. To quantify the improvement offered by these new virtual fields, they were compared with stiffness-based and manually defined virtual fields. The proposed sensitivity-based virtual fields were consistently able to identify plastic model parameters and outperform the stiffness-based and manually defined virtual fields when the data was corrupted by noise.
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On virtual displacement and virtual work in Lagrangian dynamics
International Nuclear Information System (INIS)
Ray, Subhankar; Shamanna, J
2006-01-01
The confusion and ambiguity encountered by students in understanding virtual displacement and virtual work is discussed in this paper. A definition of virtual displacement is presented that allows one to express them explicitly for holonomic (velocity independent), non-holonomic (velocity dependent), scleronomous (time independent) and rheonomous (time dependent) constraints. It is observed that for holonomic, scleronomous constraints, the virtual displacements are the displacements allowed by the constraints. However, this is not so for a general class of constraints. For simple physical systems, it is shown that the work done by the constraint forces on virtual displacements is zero. This motivates Lagrange's extension of d'Alembert's principle to a system of particles in constrained motion. However, a similar zero work principle does not hold for the allowed displacements. It is also demonstrated that d'Alembert's principle of zero virtual work is necessary for the solvability of a constrained mechanical problem. We identify this special class of constraints, physically realized and solvable, as the ideal constraints. The concept of virtual displacement and the principle of zero virtual work by constraint forces are central to both Lagrange's method of undetermined multipliers and Lagrange's equations in generalized coordinates
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1993-04-01
until exhausted. SECURITY CLASSIFICATION OF THIS PAGE All other editions are obsolete. UNCLASSIFIED " VIRTUAL REALITY JAMES F. DAILEY, LIEUTENANT COLONEL...US" This paper reviews the exciting field of virtual reality . The author describes the basic concepts of virtual reality and finds that its numerous...potential benefits to society could revolutionize everyday life. The various components that make up a virtual reality system are described in detail
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Framework for Virtual Cognitive Experiment in Virtual Geographic Environments
Directory of Open Access Journals (Sweden)
Fan Zhang
2018-01-01
Full Text Available Virtual Geographic Environment Cognition is the attempt to understand the human cognition of surface features, geographic processes, and human behaviour, as well as their relationships in the real world. From the perspective of human cognition behaviour analysis and simulation, previous work in Virtual Geographic Environments (VGEs has focused mostly on representing and simulating the real world to create an ‘interpretive’ virtual world and improve an individual’s active cognition. In terms of reactive cognition, building a user ‘evaluative’ environment in a complex virtual experiment is a necessary yet challenging task. This paper discusses the outlook of VGEs and proposes a framework for virtual cognitive experiments. The framework not only employs immersive virtual environment technology to create a realistic virtual world but also involves a responsive mechanism to record the user’s cognitive activities during the experiment. Based on the framework, this paper presents two potential implementation methods: first, training a deep learning model with several hundred thousand street view images scored by online volunteers, with further analysis of which visual factors produce a sense of safety for the individual, and second, creating an immersive virtual environment and Electroencephalogram (EEG-based experimental paradigm to both record and analyse the brain activity of a user and explore what type of virtual environment is more suitable and comfortable. Finally, we present some preliminary findings based on the first method.
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Borehole environmental tracers for evaluating net infiltration and recharge through desert bedrock
Heilweil, V.M.; Solomon, D.K.; Gardner, P.M.
2006-01-01
Permeable bedrock aquifers in arid regions are being increasingly developed as water supplies, yet little is generally known about recharge processes and spatial and temporal variability. Environmental tracers from boreholes were used in this study to investigate net infiltration and recharge to the fractured Navajo Sandstone aquifer. Vadose zone tracer profiles at the Sand Hollow study site in southwestern Utah look similar to those of desert soils at other sites, indicating the predominance of matrix flow. However, recharge rates are generally higher in the Navajo Sandstone than in unconsolidated soils in similar climates because the sandstone matrix allows water movement but not root penetration. Water enters the vadose zone either as direct infiltration of precipitation through exposed sandstone and sandy soils or as focused infiltration of runoff. Net infiltration and recharge exhibit extreme spatial variability. High-recharge borehole sites generally have large amounts of vadose zone tritium, low chloride concentrations, and small vadose zone oxygen-18 evaporative shifts. Annual net-infiltration and recharge rates at different locations range from about 1 to 60 mm as determined using vadose zone tritium, 0 to 15 mm using vadose zone chloride, and 3 to 60 mm using groundwater chloride. Environmental tracers indicate a cyclical net-infiltration and recharge pattern, with higher rates earlier in the Holocene and lower rates during the late Holocene, and a return to higher rates during recent decades associated with anomalously high precipitation during the latter part of the 20th century. The slightly enriched stable isotopic composition of modern groundwater indicates this recent increase in precipitation may be caused by a stronger summer monsoon or winter southern Pacific El Nin??o storm track. ?? Soil Science Society of America.
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Barbalios, N.; Ioannidou, I.; Tzionas, P.; Paraskeuopoulos, S.
2013-01-01
This paper introduces a realistic 3D model supported virtual environment for environmental education, that highlights the importance of water resource sharing by focusing on the tragedy of the commons dilemma. The proposed virtual environment entails simulations that are controlled by a multi-agent simulation model of a real ecosystem consisting…
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DEFF Research Database (Denmark)
Westergaard, Michael
2006-01-01
This paper introduces the notion of game coloured Petri nets. This allows the modeler to explicitly model what parts of the model comprise the modeled system and what parts are the environment of the modeled system. We give the formal definition of game coloured Petri nets, a means of reachability...... analysis of this net class, and an application of game coloured Petri nets to automatically generate easy-to-understand visualizations of the model by exploiting the knowledge that some parts of the model are not interesting from a visualization perspective (i.e. they are part of the environment...
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Water-controlled wealth of nations.
Suweis, Samir; Rinaldo, Andrea; Maritan, Amos; D'Odorico, Paolo
2013-03-12
Population growth is in general constrained by food production, which in turn depends on the access to water resources. At a country level, some populations use more water than they control because of their ability to import food and the virtual water required for its production. Here, we investigate the dependence of demographic growth on available water resources for exporting and importing nations. By quantifying the carrying capacity of nations on the basis of calculations of the virtual water available through the food trade network, we point to the existence of a global water unbalance. We suggest that current export rates will not be maintained and consequently we question the long-term sustainability of the food trade system as a whole. Water-rich regions are likely to soon reduce the amount of virtual water they export, thus leaving import-dependent regions without enough water to sustain their populations. We also investigate the potential impact of possible scenarios that might mitigate these effects through (i) cooperative interactions among nations whereby water-rich countries maintain a tiny fraction of their food production available for export, (ii) changes in consumption patterns, and (iii) a positive feedback between demographic growth and technological innovations. We find that these strategies may indeed reduce the vulnerability of water-controlled societies.
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Global net primary production and heterotrophic respiration for 1987
Energy Technology Data Exchange (ETDEWEB)
Hunt, R.E. Jr.; Piper, S.C.; Nemani, R. [Univ. of Montana, Missoula, MT (United States)]|[Scripps Institute of Oceanography, La Jolla, CA (United States)] [and others
1995-06-01
An ecosystem process model, BIOME-BGC, was parameterized and used to simulate the actual net primary production and heterotrophic respiration using daily climatic data, land cover type, leaf area index gridded to 1{degree} latitude by 1{degree} longitude grid cells for the year 1987. Global net primary production was 52 Pg C. These estimates were validated directly by two different methods. First, the grid cells were aggregated and used as inputs to a 3D atmospheric transport model, to compare CO{sub 2} station data with predictions. We simulated the intra-annual variation of atmospheric CO{sub 2} well for the northern hemisphere, but not for the southern hemisphere. Second, we calculated the net {sup 13}C uptake of vegetation, which is a function of water use efficiency. The {sup 13}C/{sup 12}C ratios agreed with measured data, indicating a strong limitation of global primary processes by the hydrologic cycle, especially precipitation. These are different from other global carbon models as we can simulate the year-to-year variation of climate, including El Nino, on the global carbon cycle.
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Tritium systems concepts for the next European torus (NET)
International Nuclear Information System (INIS)
Sood, S.K.; Bagli, K.S.; Busigin, A.; Kveton, O.K.; Dombra, A.H.; Miller, A.I.
1986-09-01
The study deals with the design of the various tritium processing facilities that will be required for the Next European Torus (NET) design. The reference data for the design of the NET Tritium Systems was provided by the NET team. Significant achievements of this study were: (a) Identification of new ways of handling some problems for example: 1) Recovery of tritium from the helium purge of the lithium-ceramic blanket using a novel Adsoprtion and Catalytic Exchange Process, 2) A new way of combining fuel component separation and coolant water detritiation using cryogenic distillation, 3) The use of parasitic refrigeration for the cryogenic isotope separation, 4) Tritium extraction from effluent gas streams at their respective sources, 5) Attempt to eliminate the need for Air Cleanup Systems. (b) Identification of uncertainties, for example: composition of plasma exhaust, required helium purge rate of Li-Pb for tritium recovery, uncertainty in requirements for decontaminating blanket sectors, etc. (c) Review of ways to limit tritium permeation into steam by swamping with hydrogen and to provide quantitative estimates for this permeation
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Virtualization Security Combining Mandatory Access Control and Virtual Machine Introspection
Win, Thu Yein; Tianfield, Huaglory; Mair, Quentin
2014-01-01
Virtualization has become a target for attacks in cloud computing environments. Existing approaches to protecting the virtualization environment against the attacks are limited in protection scope and are with high overheads. This paper proposes a novel virtualization security solution which aims to provide comprehensive protection of the virtualization environment.
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Climatic Forecasting of Net Infiltration at Yucca Mountain Using Analogue Meteorological Data
International Nuclear Information System (INIS)
Faybishenko, Boris
2005-01-01
At Yucca Mountain, NV, future changes in climatic conditions will probably alter net infiltration, drainage below the bottom of the evapotranspiration zone within the soil profile, or flow across the interface between soil and the densely welded part of the Tiva Canyon Tuff. The objectives of this study were to: (1) develop a semiempirical model and forecast average net infiltration rates, using the limited meteorological data from analog meteorological stations, for interglacial(present day), and future monsoon, glacial transition, and glacial climates over the Yucca Mountain region; and (2) corroborate the computed net infiltration rates by comparing them with the empirically and numerically determined groundwater recharge and percolation rates through the unsaturated zone from published data. This study approached calculations of net infiltration, aridity, and precipitation effectiveness indices using a modified Budyko's water-balance model, with reference-surface potential evapotranspiration determined from the radiation-based Penman formula. Results of calculations show that net infiltration rates are expected to generally increase from the present-day climate to monsoon climate, to glacial transition climate, and then to the glacial climate, following a power law relationship between net infiltration and precipitation. The forecasting results indicate the overlap between the ranges of net infiltration for different climates. Forecasting of net infiltration for different climate states is subject to numerous uncertainties associated with selecting climate analog sites, using relatively short analog meteorological records, neglecting the effects of vegetation and surface runoff and run-on on a local scale, as well as possible anthropogenically induced climate changes
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DEFF Research Database (Denmark)
Jensen, Kurt
1991-01-01
This paper describes how Coloured Petri Nets (CP-nets) have been developed — from being a promising theoretical model to being a full-fledged language for the design, specification, simulation, validation and implementation of large software systems (and other systems in which human beings and...
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Water footprint as a tool for integrated water resources management
Aldaya, Maite; Hoekstra, Arjen
2010-05-01
In a context where water resources are unevenly distributed and, in some regions precipitation and drought conditions are increasing, enhanced water management is a major challenge to final consumers, businesses, water resource users, water managers and policymakers in general. By linking a large range of sectors and issues, virtual water trade and water footprint analyses provide an appropriate framework to find potential solutions and contribute to a better management of water resources. The water footprint is an indicator of freshwater use that looks not only at direct water use of a consumer or producer, but also at the indirect water use. The water footprint of a product is the volume of freshwater used to produce the product, measured over the full supply chain. It is a multi-dimensional indicator, showing water consumption volumes by source and polluted volumes by type of pollution; all components of a total water footprint are specified geographically and temporally. The water footprint breaks down into three components: the blue (volume of freshwater evaporated from surface or groundwater systems), green (water volume evaporated from rainwater stored in the soil as soil moisture) and grey water footprint (the volume of polluted water associated with the production of goods and services). Closely linked to the concept of water footprint is that of virtual water trade, which represents the amount of water embedded in traded products. Many nations save domestic water resources by importing water-intensive products and exporting commodities that are less water intensive. National water saving through the import of a product can imply saving water at a global level if the flow is from sites with high to sites with low water productivity. Virtual water trade between nations and even continents could thus be used as an instrument to improve global water use efficiency and to achieve water security in water-poor regions of the world. The virtual water trade
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Use of the Budyko Framework to Estimate the Virtual Water Content in Shijiazhuang Plain, North China
Zhang, E.; Yin, X.
2017-12-01
One of the most challenging steps in implementing analysis of virtual water content (VWC) of agricultural crops is how to properly assess the volume of consumptive water use (CWU) for crop production. In practice, CWU is considered equivalent to the crop evapotranspiration (ETc). Following the crop coefficient method, ETc can be calculated under standard or non-standard conditions by multiplying the reference evapotranspiration (ET0) by one or a few coefficients. However, when current crop growing conditions deviate from standard conditions, accurately determining the coefficients under non-standard conditions remains to be a complicated process and requires lots of field experimental data. Based on regional surface water-energy balance, this research integrates the Budyko framework into the traditional crop coefficient approach to simplify the coefficients determination. This new method enables us to assess the volume of agricultural VWC only based on some hydrometeorological data and agricultural statistic data in regional scale. To demonstrate the new method, we apply it to the Shijiazhuang Plain, which is an agricultural irrigation area in the North China Plain. The VWC of winter wheat and summer maize is calculated and we further subdivide VWC into blue and green water components. Compared with previous studies in this study area, VWC calculated by the Budyko-based crop coefficient approach uses less data and agrees well with some of the previous research. It shows that this new method may serve as a more convenient tool for assessing VWC.
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Directory of Open Access Journals (Sweden)
felichesmi Selestine lyakurwa
2014-05-01
Full Text Available A comprehensive understanding of the link between water footprint and energy content of crop and animal products is vitally important for the sound management of water resources. In this study, we developed a mathematical relationship between water content, and energy content of many crops and animal products by using an improved LCA approach (water footprint. The standard values of the water and energy contents of crops and animal products were obtained from the databases of Agricultural Research Service, UNESCO Institute for water education and Food, and Agriculture Organization of the United Nations. The water footprint approach was applied to analyze the relationship between water requirement and energy of content of crop and animal products, in which the uncertainty and sensitivity was evaluated by Monte Carlo simulation technique that is contained in the Oracle Crystal Ball Fusion Edition v11.1.1.3.00. The results revealed significant water saving due to changes in food consumption pattern i.e. from consumption of more meat to vegetables. The production of 1kcal of crop and animal products requires about 98% of green, 4.8% blue water and 0.4% of gray water. In which changes in consumption pattern gave annual blue water saving of about 1605 Mm3 that is equivalent to 41.30m3/capita, extremely greater than the standard drinking water requirement for the whole population. Moreover, the projected results indicated, triple increase of dietary water requirement from 30.9 Mm3 in 2005 to 108 Mm3 by 2050. It was also inferred that, Tanzania has a positive virtual water balance of crop and animal products consumption with net virtual water import of 9.1 Mm3 that is the contribution margin to the water scarcity alleviation strategy. Therefore, developed relationship of water footprint and energy content of crops and animal products can be used by water resource experts for sustainable freshwater and food supply.
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Towards new information resources for public health--from WordNet to MedicalWordNet.
Fellbaum, Christiane; Hahn, Udo; Smith, Barry
2006-06-01
In the last two decades, WordNet has evolved as the most comprehensive computational lexicon of general English. In this article, we discuss its potential for supporting the creation of an entirely new kind of information resource for public health, viz. MedicalWordNet. This resource is not to be conceived merely as a lexical extension of the original WordNet to medical terminology; indeed, there is already a considerable degree of overlap between WordNet and the vocabulary of medicine. Instead, we propose a new type of repository, consisting of three large collections of (1) medically relevant word forms, structured along the lines of the existing Princeton WordNet; (2) medically validated propositions, referred to here as medical facts, which will constitute what we shall call MedicalFactNet; and (3) propositions reflecting laypersons' medical beliefs, which will constitute what we shall call the MedicalBeliefNet. We introduce a methodology for setting up the MedicalWordNet. We then turn to the discussion of research challenges that have to be met to build this new type of information resource. We build a database of sentences relevant to the medical domain. The sentences are generated from WordNet via its relations as well as from medical statements broken down into elementary propositions. Two subcorpora of sentences are distinguished, MedicalBeliefNet and MedicalFactNet. The former is rated for assent by laypersons; the latter for correctness by medical experts. The sentence corpora will be valuable for a variety of applications in information retrieval as well as in research in linguistics and psychology with respect to the study of expert and non-expert beliefs and their linguistic expressions. Our work has to meet several considerable challenges. These include accounting for the distinction between medical experts and laypersons, the social issues of expert-layperson communication in different media, the linguistic aspects of encoding medical knowledge, and
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Lin, Chien-Hung
2017-05-01
We generalize the string-net construction to multiple flavors of strings, each of which is labeled by the elements of an Abelian group Gi. The same flavor of strings can branch, while different flavors of strings can cross one another and thus they form intersecting string nets. We systematically construct the exactly soluble lattice Hamiltonians and the ground-state wave functions for the intersecting string-net condensed phases. We analyze the braiding statistics of the low-energy quasiparticle excitations and find that our model can realize all the topological phases as the string-net model with group G =∏iGi . In this respect, our construction provides various ways of building lattice models which realize topological order G , corresponding to different partitions of G and thus different flavors of string nets. In fact, our construction concretely demonstrates the Künneth formula by constructing various lattice models with the same topological order. As an example, we construct the G =Z2×Z2×Z2 string-net model which realizes a non-Abelian topological phase by properly intersecting three copies of toric codes.
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Water footprints of cities - indicators for sustainable consumption and production
Hoff, H.; Döll, P.; Fader, M.; Gerten, D.; Hauser, S.; Siebert, S.
2014-01-01
Water footprints have been proposed as sustainability indicators, relating the consumption of goods like food to the amount of water necessary for their production and the impacts of that water use in the source regions. We further developed the existing water footprint methodology, by globally resolving virtual water flows from production to consumption regions for major food crops at 5 arcmin spatial resolution. We distinguished domestic and international flows, and assessed local impacts of export production. Applying this method to three exemplary cities, Berlin, Delhi and Lagos, we find major differences in amounts, composition, and origin of green and blue virtual water imports, due to differences in diets, trade integration and crop water productivities in the source regions. While almost all of Delhi's and Lagos' virtual water imports are of domestic origin, Berlin on average imports from more than 4000 km distance, in particular soy (livestock feed), coffee and cocoa. While 42% of Delhi's virtual water imports are blue water based, the fractions for Berlin and Lagos are 2 and 0.5%, respectively, roughly equal to the water volumes abstracted in these two cities for domestic water use. Some of the external source regions of Berlin's virtual water imports appear to be critically water scarce and/or food insecure. However, for deriving recommendations on sustainable consumption and trade, further analysis of context-specific costs and benefits associated with export production will be required.
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Rare, but challenging tumors: NET
International Nuclear Information System (INIS)
Ivanova, D.; Balev, B.
2013-01-01
Full text: Introduction: Gastroenteropancreatic Neuroendocrine Tumors (GEP - NET) are a heterogeneous group of tumors with different locations and many different clinical, histological, and imaging performance. In a part of them a secretion of various organic substances is present. The morbidity of GEP - NET in the EU is growing, and this leads to increase the attention to them. What you will learn: Imaging methods used for localization and staging of GEP - NET, characteristics of the study’s protocols; Classification of GEP - NET; Demonstration of typical and atypical imaging features of GEP - NET in patients registered at the NET Center at University Hospital ‘St. Marina’, Varna; Features of metastatic NET, The role of imaging in the evaluation of treatment response and follow-up of the patients. Discussion: The image semiotics analysis is based on 19 cases of GEP - NET registered NET Center at University Hospital ‘St. Marina’. The main imaging method is multidetector CT (MDCT), and magnetic resonance imaging (MRI ) has advantages in the evaluation of liver lesions and the local prevalence of anorectal tumors. In patients with advanced disease and liver lesions the assessment of skeletal involvement (MRI/ nuclear medical method) is mandatory. The majority of GEP - NET have not any specific imaging findings. Therefore it is extremely important proper planning and conducting of the study (MDCT and MR enterography; accurate assessment phase of scanning, positive and negative contrast). Conclusion: GEP - NET is a major diagnostic challenge due to the absence of typical imaging characteristics and often an overlap with those of the tumors of different origin can be observed. Therefore, a good knowledge of clinical and imaging changes occurring at different locations is needed. MDCT is the basis for the diagnosis, staging and follow-up of these neoplasms
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ShadowNet: An Active Defense Infrastructure for Insider Cyber Attack Prevention
Energy Technology Data Exchange (ETDEWEB)
Cui, Xiaohui [ORNL; Beaver, Justin M [ORNL; Treadwell, Jim N [ORNL
2012-01-01
The ShadowNet infrastructure for insider cyber attack prevention is comprised of a tiered server system that is able to dynamically redirect dangerous/suspicious network traffic away from production servers that provide web, ftp, database and other vital services to cloned virtual machines in a quarantined environment. This is done transparently from the point of view of both the attacker and normal users. Existing connections, such as SSH sessions, are not interrupted. Any malicious activity performed by the attacker on a quarantined server is not reflected on the production server. The attacker is provided services from the quarantined server, which creates the impression that the attacks performed are successful. The activities of the attacker on the quarantined system are able to be recorded much like a honeypot system for forensic analysis.
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DEFF Research Database (Denmark)
Davis, Hilary; Skov, Mikael B.; Stougaard, Malthe
2007-01-01
. This paper reports on the design, implementation and initial evaluation of Virtual Box. Virtual Box attempts to create a physical and engaging context in order to support reciprocal interactions with expressive content. An implemented version of Virtual Box is evaluated in a location-aware environment...
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International Nuclear Information System (INIS)
Smirnov, A; Alekseev, G; Korablev, A; Esau, I
2010-01-01
The Nordic Seas are an important area of the World Ocean where warm Atlantic waters penetrate far north forming the mild climate of Northern Europe. These waters represent the northern rim of the global thermohaline circulation. Estimates of the relationships between the net heat flux and mixed layer properties in the Nordic Seas are examined. Oceanographic data are derived from the Oceanographic Data Base (ODB) compiled in the Arctic and Antarctic Research Institute. Ocean weather ship 'Mike' (OWS) data are used to calculate radiative and turbulent components of the net heat flux. The net shortwave flux was calculated using a satellite albedo dataset and the EPA model. The net longwave flux was estimated by Southampton Oceanography Centre (SOC) method. Turbulent fluxes at the air-sea interface were calculated using the COARE 3.0 algorithm. The net heat flux was calculated by using oceanographic and meteorological data of the OWS 'Mike'. The mixed layer depth was estimated for the period since 2002 until 2009 by the 'Mike' data as well. A good correlation between these two parameters has been found. Sensible and latent heat fluxes controlled by surface air temperature/sea surface temperature gradient are the main contributors into net heat flux. Significant correlation was found between heat fluxes variations at the OWS 'Mike' location and sea ice export from the Arctic Ocean.
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Energy Technology Data Exchange (ETDEWEB)
Smirnov, A; Alekseev, G [SI ' Arctic and Antarctic Research Institute' , St. Petersburg (Russian Federation); Korablev, A; Esau, I, E-mail: avsmir@aari.nw.r [Nansen Environmental and Remote Sensing Centre, Bergen (Norway)
2010-08-15
The Nordic Seas are an important area of the World Ocean where warm Atlantic waters penetrate far north forming the mild climate of Northern Europe. These waters represent the northern rim of the global thermohaline circulation. Estimates of the relationships between the net heat flux and mixed layer properties in the Nordic Seas are examined. Oceanographic data are derived from the Oceanographic Data Base (ODB) compiled in the Arctic and Antarctic Research Institute. Ocean weather ship 'Mike' (OWS) data are used to calculate radiative and turbulent components of the net heat flux. The net shortwave flux was calculated using a satellite albedo dataset and the EPA model. The net longwave flux was estimated by Southampton Oceanography Centre (SOC) method. Turbulent fluxes at the air-sea interface were calculated using the COARE 3.0 algorithm. The net heat flux was calculated by using oceanographic and meteorological data of the OWS 'Mike'. The mixed layer depth was estimated for the period since 2002 until 2009 by the 'Mike' data as well. A good correlation between these two parameters has been found. Sensible and latent heat fluxes controlled by surface air temperature/sea surface temperature gradient are the main contributors into net heat flux. Significant correlation was found between heat fluxes variations at the OWS 'Mike' location and sea ice export from the Arctic Ocean.
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Limitations of shallow nets approximation.
Lin, Shao-Bo
2017-10-01
In this paper, we aim at analyzing the approximation abilities of shallow networks in reproducing kernel Hilbert spaces (RKHSs). We prove that there is a probability measure such that the achievable lower bound for approximating by shallow nets can be realized for all functions in balls of reproducing kernel Hilbert space with high probability, which is different with the classical minimax approximation error estimates. This result together with the existing approximation results for deep nets shows the limitations for shallow nets and provides a theoretical explanation on why deep nets perform better than shallow nets. Copyright © 2017 Elsevier Ltd. All rights reserved.
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Graphics interfaces and numerical simulations: Mexican Virtual Solar Observatory
Hernández, L.; González, A.; Salas, G.; Santillán, A.
2007-08-01
Preliminary results associated to the computational development and creation of the Mexican Virtual Solar Observatory (MVSO) are presented. Basically, the MVSO prototype consists of two parts: the first, related to observations that have been made during the past ten years at the Solar Observation Station (EOS) and at the Carl Sagan Observatory (OCS) of the Universidad de Sonora in Mexico. The second part is associated to the creation and manipulation of a database produced by numerical simulations related to solar phenomena, we are using the MHD ZEUS-3D code. The development of this prototype was made using mysql, apache, java and VSO 1.2. based GNU and `open source philosophy'. A graphic user interface (GUI) was created in order to make web-based, remote numerical simulations. For this purpose, Mono was used, because it is provides the necessary software to develop and run .NET client and server applications on Linux. Although this project is still under development, we hope to have access, by means of this portal, to other virtual solar observatories and to be able to count on a database created through numerical simulations or, given the case, perform simulations associated to solar phenomena.
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Tang, Hao; Hu, Fuxiang; Xu, Liuxiong; Dong, Shuchuang; Zhou, Cheng; Wang, Xuefang
2017-10-01
Knotless polyethylene (PE) netting has been widely used in aquaculture cages and fishing gears, especially in Japan. In this study, the hydrodynamic coefficient of six knotless PE netting panels with different solidity ratios were assessed in a flume tank under various attack angles of netting from 0° (parallel to flow) to 90° (perpendicular to flow) and current speeds from 40 cm s-1 to 130 cm s-1. It was found that the drag coefficient was related to Reynolds number, solidity ratio and attack angle of netting. The solidity ratio was positively related with drag coefficient for netting panel perpendicular to flow, whereas when setting the netting panel parallel to the flow the opposite result was obtained. For netting panels placed at an angle to the flow, the lift coefficient reached the maximum at an attack angle of 50° and then decreased as the attack angle further increased. The solidity ratio had a dual influence on drag coefficient of inclined netting panels. Compared to result in the literature, the normal drag coefficient of knotless PE netting measured in this study is larger than that of nylon netting or Dyneema netting.
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Xu, Jian-wei; Liao, Yuan-mei; Liu, Hui; Nie, Ren-hua; Havumaki, Joshua
2014-01-01
Insecticide-treated nets (ITNs) are an integral part of vector control recommendations for malaria elimination in China. This study investigated the extent to which bed nets were used and which factors influence bed net use among Jinuo Ethnic Minority in China-Myanmar-Laos border areas. This study combined a quantitative household questionnaire survey and qualitative semi-structured in-depth interviews (SDI). Questionnaires were administered to 352 heads of households. SDIs were given to 20 key informants. The bed net to person ratio was 1∶2.1 (i.e., nearly one net for every two people), however only 169 (48.0%) households owned at least one net and 623 (47.2%) residents slept under bed nets the prior night. The percentages of residents who regularly slept under nets (RSUN) and slept under nets the prior night (SUNPN) were similar (48.0% vs. 47.2%, P>0.05), however the percentage correct use of nets (CUN) was significantly lower (34.5%, Pcash income per person (ACIP) was an independent factor that influenced bed net use (PHigh bed net availability does not necessarily mean higher coverage or bed net use. Household income, house type and knowledge of the ability of bed nets to prevent malaria are all independent factors that influence bed net use among Jinuo Ethnic Minority.
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International Nuclear Information System (INIS)
Spears, B.
1987-01-01
The paper concerns the next generation of fusion machines which are intended to demonstrate the technical viability of fusion. In Europe, the device that will follow on from JET is known as NET - the Next European Torus. If the design programme for NET proceeds, Europe could start to build the machine in 1994. The present JET programme hopes to achieve breakeven in the early 1990's. NET hopes to reach ignition in the next century, and so lay the foundation for a demonstration reactor. A description is given of the technical specifications of the components of NET, including: the first wall, the divertors to protect the wall, the array of magnets that provide the fields containing the plasma, the superconducting magnets, and the shield of the machine. NET's research programme is briefly outlined, including the testing programme to optimise conditions in the machine to achieve ignition, and its safety work. (U.K.)
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1993-01-01
This is the Final Technical Report for the NetView Technical Research task. This report is prepared in accordance with Contract Data Requirements List (CDRL) item A002. NetView assistance was provided and details are presented under the following headings: NetView Management Systems (NMS) project tasks; WBAFB IBM 3090; WPAFB AMDAHL; WPAFB IBM 3084; Hill AFB; McClellan AFB AMDAHL; McClellan AFB IBM 3090; and Warner-Robins AFB.
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Carbon dioxide addition to coral reef waters suppresses net community calcification
Albright, Rebecca; Takeshita, Yuichiro; Koweek, David A.; Ninokawa, Aaron; Wolfe, Kennedy; Rivlin, Tanya; Nebuchina, Yana; Young, Jordan; Caldeira, Ken
2018-03-01
Coral reefs feed millions of people worldwide, provide coastal protection and generate billions of dollars annually in tourism revenue. The underlying architecture of a reef is a biogenic carbonate structure that accretes over many years of active biomineralization by calcifying organisms, including corals and algae. Ocean acidification poses a chronic threat to coral reefs by reducing the saturation state of the aragonite mineral of which coral skeletons are primarily composed, and lowering the concentration of carbonate ions required to maintain the carbonate reef. Reduced calcification, coupled with increased bioerosion and dissolution, may drive reefs into a state of net loss this century. Our ability to predict changes in ecosystem function and associated services ultimately hinges on our understanding of community- and ecosystem-scale responses. Past research has primarily focused on the responses of individual species rather than evaluating more complex, community-level responses. Here we use an in situ carbon dioxide enrichment experiment to quantify the net calcification response of a coral reef flat to acidification. We present an estimate of community-scale calcification sensitivity to ocean acidification that is, to our knowledge, the first to be based on a controlled experiment in the natural environment. This estimate provides evidence that near-future reductions in the aragonite saturation state will compromise the ecosystem function of coral reefs.
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Kweka, Eliningaya J; Lyaruu, Lucile J; Mahande, Aneth M
2017-01-18
Mosquitoes have developed resistance against pyrethroids, the only class of insecticides approved for use on long-lasting insecticidal nets (LLINs). The present study sought to evaluate the efficacy of the pyrethroid synergist PermaNet® 3.0 LLIN versus the pyrethroid-only PermaNet® 2.0 LLIN, in an East African hut design in Lower Moshi, northern Tanzania. In this setting, resistance to pyrethroid insecticides has been identified in Anopheles gambiae mosquitoes. Standard World Health Organization bioefficacy evaluations were conducted in both laboratory and experimental huts. Experimental hut evaluations were conducted in an area where there was presence of a population of highly pyrethroid-resistant An. arabiensis mosquitoes. All nets used were subjected to cone bioassays and then to experimental hut trials. Mosquito mortality, blood-feeding inhibition and personal protection rate were compared between untreated nets, unwashed LLINs and LLINs that were washed 20 times. Both washed and unwashed PermaNet® 2.0 and PermaNet® 3.0 LLINs had knockdown and mortality rates of 100% against a susceptible strain of An. gambiae sensu stricto. The adjusted mortality rate of the wild mosquito population after use of the unwashed PermaNet® 3.0 and PermaNet® 2.0 nets was found to be higher than after use of the washed PermaNet® 2.0 and PermaNet® 3.0 nets. Given the increasing incidence of pyrethroid resistance in An. gambiae mosquitoes in Tanzania, we recommend that consideration is given to its distribution in areas with pyrethroid-resistant malaria vectors within the framework of a national insecticide-resistance management plan.
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PODATKOVNE STORITVE ADO.NET IN ADO.NET ENTITY FRAMEWORK
Volavc, Franc
2012-01-01
V diplomskem delu smo predstavili Microsoftovi ogrodji ADO.NET in ADO.NET Entity Framework. Preučili in analizirali smo metode za dostop do podatkovnih virov, ki jih ponujata ogrodji, ter nato te ugotovitve preslikati v odločitveno drevo, katero bo programerjem in razvijalcem informacijskih sistemov pomagalo pri odločanju glede pristopa za dostop do podatkovnih virov. Ker bomo v diplomskem delu predstavili Microsoftovi ogrodji, bomo posledično omejeni zgolj na Microsoftovo tehnologijo, se pra...
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Realidad virtual y materialidad
Pérez Herranz, Fernando Miguel
2009-01-01
1. Fenomenología de partida: Real / Simbólico / Imaginario 2. Realidad 3. Virtual 3.1. Virtual / real / posible / probable 3.2. Los contextos de la realidad virtual A) REALIDAD VIRTUAL INMERSIVA B) REALIDAD VIRTUAL NO INMERSIVA C) REALIDAD VIRTUAL Y DIGITALIZACIÓN 3.3. Cruce virtual / real 3.4. Cuestiones filosóficas 4. Materialidad 5. Materialidad y descentramiento 5.1. Ejemplos de descentramiento en los contextos de Realidad Virtual A’) DUALISMO CARTESIANO, CUERPO Y «CIBORG » B’) EL ESPÍRIT...
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Directory of Open Access Journals (Sweden)
D. Karimanzira
2014-12-01
Full Text Available Recently, underwater vehicles have become low cost, reliable and affordable platforms for performing various underwater tasks. While many aquaculture systems are closed with no harmful output, open net cage fish farms and land-based fish farms can discharge significant amounts of wastewater containing nutrients, chemicals, and pharmaceuticals that impact on the surrounding environment. Although aquaculture development has often occurred outside a regulatory framework, government oversight is increasingly common at both the seafood quality control level, and at baseline initiatives addressing the basic problem of pollution generated by culture operations, e.g. the European marine and maritime directives. This requires regular, sustainable and cost-effective monitoring of the water quality. Such monitoring needs devices to detect the water quality in a large sea area at different depths in real time. This paper presents a concept for a guidance system for a carrier (an autonomous underwater vehicle of such devices for the automated detection and analysis of water quality parameters.
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A virtual network computer's optical storage virtualization scheme
Wang, Jianzong; Hu, Huaixiang; Wan, Jiguang; Wang, Peng
2008-12-01
In this paper, we present the architecture and implementation of a virtual network computers' (VNC) optical storage virtualization scheme called VOSV. Its task is to manage the mapping of virtual optical storage to physical optical storage, a technique known as optical storage virtualization. The design of VOSV aims at the optical storage resources of different clients and servers that have high read-sharing patterns. VOSV uses several schemes such as a two-level Cache mechanism, a VNC server embedded module and the iSCSI protocols to improve the performance. The results measured on the prototype are encouraging, and indicating that VOSV provides the high I/O performance.
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International Nuclear Information System (INIS)
Rogalla, P.; Meiri, N.; Hamm, B.; Rueckert, J.C.; Schmidt, B.; Witt, C.
2001-01-01
Flexible bronchoscopy represents a clinically well-established invasive diagnostic tool. Virtual bronchoscopies, calculated from thin-slice CT sections, allow astonishing immitations of reality although principal differences exist between both technologies: the Fact that colour representation is artificial and concommitant interventions are impossible limits the clinical use of virtual bronchoscopy. However, its value increases when calculations can be attained within minutes due to technological advancements, and when virtually any chest CT is suitable for further postprocessing. Indications, findings and the clinical role of virtual bronchoscopy are discussed. (orig.) [de
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Magirl, Christopher S.; Breedlove, Michael J.; Webb, Robert H.; Griffiths, Peter G.
2008-01-01
Using widely-available software intended for modeling rivers, a new one-dimensional hydraulic model was developed for the Colorado River through Grand Canyon from Lees Ferry to Diamond Creek. Solving one-dimensional equations of energy and continuity, the model predicts stage for a known steady-state discharge at specific locations, or cross sections, along the river corridor. This model uses 2,680 cross sections built with high-resolution digital topography of ground locations away from the river flowing at a discharge of 227 m3/s; synthetic bathymetry was created for topography submerged below the 227 m3/s water surface. The synthetic bathymetry was created by adjusting the water depth at each cross section up or down until the model?s predicted water-surface elevation closely matched a known water surface. This approach is unorthodox and offers a technique to construct one-dimensional hydraulic models of bedrock-controlled rivers where bathymetric data have not been collected. An analysis of this modeling approach shows that while effective in enabling a useful model, the synthetic bathymetry can differ from the actual bathymetry. The known water-surface profile was measured using elevation data collected in 2000 and 2002, and the model can simulate discharges up to 5,900 m3/s. In addition to the hydraulic model, GIS-based techniques were used to estimate virtual shorelines and construct inundation maps. The error of the hydraulic model in predicting stage is within 0.4 m for discharges less than 1,300 m3/s. Between 1,300-2,500 m3/s, the model accuracy is about 1.0 m, and for discharges between 2,500-5,900 m3/s, the model accuracy is on the order of 1.5 m. In the absence of large floods on the flow-regulated Colorado River in Grand Canyon, the new hydraulic model and the accompanying inundation maps are a useful resource for researchers interested in water depths, shorelines, and stage-discharge curves for flows within the river corridor with 2002 topographic
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Jones, J.S.
1999-01-12
An apparatus and method of issuing commands to a computer by a user interfacing with a virtual reality environment are disclosed. To issue a command, the user directs gaze at a virtual button within the virtual reality environment, causing a perceptible change in the virtual button, which then sends a command corresponding to the virtual button to the computer, optionally after a confirming action is performed by the user, such as depressing a thumb switch. 4 figs.
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Current Status and Future Prospect of K-NET and KiK-net
Aoi, S.; Kunugi, T.; Suzuki, W.; Nakamura, H.; Fujiwara, H.
2014-12-01
During 18 years since the deployment of K-NET following the Kobe earthquake, our attention has mainly focused on rapidity of the data collection and an unfailing and reliable observation. In this presentation, we review three generations of the instruments employed by K-NET and KiK-net from these two points of view.At beginning of the 2000's, we newly developed the second generation instruments (K-NET02, K-NET02A, KiK-net06) to replace the first generation instruments (K-NET95, SMAC-MDK) employed when the networks were constructed in the 1990's. These instruments have an automatic dial-out function. It takes typically 2-5 s to establish communication and a few seconds to send the pre-trigger data. After that, data is available typically within a 1.5 s delay. Not only waveform data but also strong motion indexes such as real-time intensity, PGA, PGV, PGD, and response spectra are continuously sent once a second.After the 2011 Tohoku earthquake, we have developed the third generation instruments (K-NET11, KiK-net11) and have replaced almost half of the all stations country wide. Main improvement of this instrument is more unfailing and reliable observation. Because we have often experienced very large ground motions (e.g. 45 records exceeding gravity), the maximum measureable range was expanded from 2000 gal to 4000 gal for the second generation instrument, and to 8000 gal for the third. For the third generation instrument, in case of power failure, observation (including transmission of data) works for seven days thanks to the backup battery, while for the second generation instruments it works only for one day. By adding an oblique component to the three-component accelerometers, we could automatically distinguish shaking data from noise such as electric pulses which may cause a false alarm in EEW. Implementation to guarantee the continuity of observation under severe conditions such as during the Tohoku earthquake is very important, as well as a highly efficient
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Mapani, Benjamin; Magole, Lapologang; Makurira, Hodson; Meck, Maideyi; Mkandawire, Theresa; Mul, Marloes; Ngongondo, Cosmo
2017-08-01
This volume has brought together papers that are peer reviewed emanating from the WaterNet/WARFSA/GWP-SA 16th Symposium. The papers cover the following themes: Hydrology, Water and Environment, Water and Land, Water and Society, Water Supply and Sanitation and Water Resources Management.
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Markets, voucher subsidies and free nets combine to achieve high bed net coverage in rural Tanzania
Directory of Open Access Journals (Sweden)
Gerrets Rene PM
2008-06-01
Full Text Available Abstract Background Tanzania has a well-developed network of commercial ITN retailers. In 2004, the government introduced a voucher subsidy for pregnant women and, in mid 2005, helped distribute free nets to under-fives in small number of districts, including Rufiji on the southern coast, during a child health campaign. Contributions of these multiple insecticide-treated net delivery strategies existing at the same time and place to coverage in a poor rural community were assessed. Methods Cross-sectional household survey in 6,331 members of randomly selected 1,752 households of 31 rural villages of Demographic Surveillance System in Rufiji district, Southern Tanzania was conducted in 2006. A questionnaire was administered to every consenting respondent about net use, treatment status and delivery mechanism. Findings Net use was 62.7% overall, 87.2% amongst infants (0 to1 year, 81.8% amongst young children (>1 to 5 years, 54.5% amongst older children (6 to 15 years and 59.6% amongst adults (>15 years. 30.2% of all nets had been treated six months prior to interview. The biggest source of nets used by infants was purchase from the private sector with a voucher subsidy (41.8%. Half of nets used by young children (50.0% and over a third of those used by older children (37.2% were obtained free of charge through the vaccination campaign. The largest source of nets amongst the population overall was commercial purchase (45.1% use and was the primary means for protecting adults (60.2% use. All delivery mechanisms, especially sale of nets at full market price, under-served the poorest but no difference in equity was observed between voucher-subsidized and freely distributed nets. Conclusion All three delivery strategies enabled a poor rural community to achieve net coverage high enough to yield both personal and community level protection for the entire population. Each of them reached their relevant target group and free nets only temporarily
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Rykowski, Jarogniew
2007-01-01
In this paper we propose an application of software agents to provide Virtual Web Services. A Virtual Web Service is a linked collection of several real and/or virtual Web Services, and public and private agents, accessed by the user in the same way as a single real Web Service. A Virtual Web Service allows unrestricted comparison, information merging, pipelining, etc., of data coming from different sources and in different forms. Detailed architecture and functionality of a single Virtual We...
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Lapshin, Rostislav V.
2016-08-01
A method of distributed calibration of a probe microscope scanner is suggested. The main idea consists in a search for a net of local calibration coefficients (LCCs) in the process of automatic measurement of a standard surface, whereby each point of the movement space of the scanner can be characterized by a unique set of scale factors. Feature-oriented scanning (FOS) methodology is used as a basis for implementation of the distributed calibration permitting to exclude in situ the negative influence of thermal drift, creep and hysteresis on the obtained results. Possessing the calibration database enables correcting in one procedure all the spatial systematic distortions caused by nonlinearity, nonorthogonality and spurious crosstalk couplings of the microscope scanner piezomanipulators. To provide high precision of spatial measurements in nanometer range, the calibration is carried out using natural standards - constants of crystal lattice. One of the useful modes of the developed calibration method is a virtual mode. In the virtual mode, instead of measurement of a real surface of the standard, the calibration program makes a surface image ;measurement; of the standard, which was obtained earlier using conventional raster scanning. The application of the virtual mode permits simulation of the calibration process and detail analysis of raster distortions occurring in both conventional and counter surface scanning. Moreover, the mode allows to estimate the thermal drift and the creep velocities acting while surface scanning. Virtual calibration makes possible automatic characterization of a surface by the method of scanning probe microscopy (SPM).
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Initial CAD investigations for NET
International Nuclear Information System (INIS)
Katz, F.; Leinemann, K.; Ludwig, A.; Marek, U.; Olbrich, W.; Schlechtendahl, E.G.
1985-11-01
This report summarizes the work done under contract no. 164/84-7/FU-D-/NET between the Commission of the European Communities and KfK during the period from June 1, 1984, through May 31, 1985. The following topics are covered in this report: Initial modelling of NET version NET2A, CAD system extension for remote handling studies, analysis of the CAD information structure, work related to the transfer of CAD information between KfK and the NET team. (orig.) [de
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Salter, David
2014-01-01
If you're a Java developer of any level using NetBeans and want to learn how to get the most out of NetBeans, then this book is for you. Learning how to utilize NetBeans will provide a firm foundation for your Java application development.
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THE NET ADVANCE OF PHYSICS Review Articles and Tutorials in an Encyclopædic Format Established 1995 [Link to MIT] Computer support for The Net Advance of Physics is furnished by The Massachusetts Newest Additions SPECIAL FEATURES: Net Advance RETRO: Nineteenth Century Physics History of Science
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International Nuclear Information System (INIS)
Bramley, A.; Clabburn, R.J.T.
1976-01-01
A method is described for producing netting composed of longitudinal and transverse threads of irradiation cross linked thermoplastic material, the threads being joined together at their crossings by moulded masses of cross linked thermoplastic material. The thread may be formed of polyethylene filaments, subjected to a radiation dose of 15 to 25 MR. The moulding can be conducted at 245 0 to 260 0 C or higher. The product is claimed to be an improved quality of netting, with bonds of increased strength between crossing threads. (U.K.)
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Molotch, N. P.; Painter, T. H.; Bales, R. C.; Dozier, J.
2003-04-01
In this study, an accumulated net radiation / accumulated degree-day index snowmelt model was coupled with remotely sensed snow covered area (SCA) data to simulate snow cover depletion and reconstruct maximum snow water equivalent (SWE) in the 19.1-km2 Tokopah Basin of the Sierra Nevada, California. Simple net radiation snowmelt models are attractive for operational snowmelt runoff forecasts as they are computationally inexpensive and have low input requirements relative to physically based energy balance models. The objective of this research was to assess the accuracy of a simple net radiation snowmelt model in a topographically heterogeneous alpine environment. Previous applications of net radiation / temperature index snowmelt models have not been evaluated in alpine terrain with intensive field observations of SWE. Solar radiation data from two meteorological stations were distributed using the topographic radiation model TOPORAD. Relative humidity and temperature data were distributed based on the lapse rate calculated between three meteorological stations within the basin. Fractional SCA data from the Landsat Enhanced Thematic Mapper (5 acquisitions) and the Airborne Visible and Infrared Imaging Spectrometer (AVIRIS) (2 acquisitions) were used to derive daily SCA using a linear regression between acquisition dates. Grain size data from AVIRIS (4 acquisitions) were used to infer snow surface albedo and interpolated linearly with time to derive daily albedo values. Modeled daily snowmelt rates for each 30-m pixel were scaled by the SCA and integrated over the snowmelt season to obtain estimates of maximum SWE accumulation. Snow surveys consisting of an average of 335 depth measurements and 53 density measurements during April, May and June, 1997 were interpolated using a regression tree / co-krig model, with independent variables of average incoming solar radiation, elevation, slope and maximum upwind slope. The basin was clustered into 7 elevation / average
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Structure functions of longitudinal virtual photons at low virtualities
International Nuclear Information System (INIS)
Ioffe, B.L.; Shushpanov, I.A.
1996-01-01
The structure functions F L 1 and F L 2 of longitudinal virtual photons at low virtualities are calculated in the framework of chiral perturbation theory (ChPT) in the zero and first order of ChPT. It is assumed that the virtuality of a target longitudinal photon p 2 is much less than the virtuality of the hard projectile photon Q 2 and both are less than the characteristic ChPT scale. In this approximation the structure functions are determined by the production of two pions in γγ collisions. The numerical results for F L 2 and F L 1 are presented (the upper index refers to the longitudinal polarization of the virtual target photon). The possibilities of measurements of these structure functions are briefly discussed. copyright 1996 The American Physical Society
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A new divertor plates design concept for the double null NET configuration
International Nuclear Information System (INIS)
Farfaletti-Casali, F.; Renda, V.; Federici, G.; Papa, L.
1986-01-01
A new divertor plate design concept for the Double Null NET configuration (NET-DN) is presented. This concept applies to the plasma configuration of NET and takes advantage by the maintenance scheme of the internal components adopted in NET. According to this maintenance approach, which uses the top loading of the internal segments, 48 inboard removable segments, 3 for each of the 16 reactor sectors, act as simple protective panels, gathering together in only one piece the plates of both the upper and lower divertor regions and the intermediate portion of the inboard first wall. They are cooled by water flowing inside a set of hairpin-shaped, stainless steel tubes, arranged in poloidal direction inside a copper heat sink, and fed by supply lines at the top of the reactor. The surface facing the plasma is covered by a tungsten alloy layer. In such a way, the maintenance of the two divertor regions and of the inboard first wall can be easily achieved by removing the inboard panels from the top of the reactor. The layout of the cooling system and preliminary thermohydraulics and thermomechanical calculations, carried out for assessing the feasibility of the proposed system for the NET reference configuration, are reported in this paper. (author)
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A new divertor plates design concept for the double null net configuration
International Nuclear Information System (INIS)
Farfaletti-Casali, F.; Iop, O.; Renda, V.; Federici, G.; Papa, L.
1987-01-01
A new divertor plate design concept for the Double Null NET configuration (NET-DN) is presented in this paper. This concept applies to the plasma configuration of NET and takes advantage by the maintenance scheme of the internal components adopted in NET. According to this maintenance approach, which uses the top loading of the internal segments, 48 inboard removable segments, 3 for each of the 16 reactor sectors, act as simple protective panels, gathering together in only one piece the plates of both the upper and lower divertor regions and the intermediate portion of the inboard first wall. They are cooled by water flowing inside a set of hairpin-shaped, stainless steel tubes, arranged in poloidal direction inside a copper heat sink, and fed by supply lines at the top of the reactor. The surface facing the plasma is covered by a tungsten alloy layer. In such a way, the maintenance of the two divertor regions and of the inboard first wall can be easily achieved by removing the inboard panels from the top of the reactor. The layout of the cooling system and preliminary thermohydraulics and thermomechanical calculations, carried out for assessing the feasibility of the proposed system for the NET reference configuration, are reported in this paper
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Virtual hand: a 3D tactile interface to virtual environments
Rogowitz, Bernice E.; Borrel, Paul
2008-02-01
We introduce a novel system that allows users to experience the sensation of touch in a computer graphics environment. In this system, the user places his/her hand on an array of pins, which is moved about space on a 6 degree-of-freedom robot arm. The surface of the pins defines a surface in the virtual world. This "virtual hand" can move about the virtual world. When the virtual hand encounters an object in the virtual world, the heights of the pins are adjusted so that they represent the object's shape, surface, and texture. A control system integrates pin and robot arm motions to transmit information about objects in the computer graphics world to the user. It also allows the user to edit, change and move the virtual objects, shapes and textures. This system provides a general framework for touching, manipulating, and modifying objects in a 3-D computer graphics environment, which may be useful in a wide range of applications, including computer games, computer aided design systems, and immersive virtual worlds.
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Net alkalinity and net acidity 1: Theoretical considerations
International Nuclear Information System (INIS)
Kirby, Carl S.; Cravotta, Charles A.
2005-01-01
Net acidity and net alkalinity are widely used, poorly defined, and commonly misunderstood parameters for the characterization of mine drainage. The authors explain theoretical expressions of 3 types of alkalinity (caustic, phenolphthalein, and total) and acidity (mineral, CO 2 , and total). Except for rarely-invoked negative alkalinity, theoretically defined total alkalinity is closely analogous to measured alkalinity and presents few practical interpretation problems. Theoretically defined 'CO 2 -acidity' is closely related to most standard titration methods with an endpoint pH of 8.3 used for determining acidity in mine drainage, but it is unfortunately named because CO 2 is intentionally driven off during titration of mine-drainage samples. Using the proton condition/mass-action approach and employing graphs to illustrate speciation with changes in pH, the authors explore the concept of principal components and how to assign acidity contributions to aqueous species commonly present in mine drainage. Acidity is defined in mine drainage based on aqueous speciation at the sample pH and on the capacity of these species to undergo hydrolysis to pH 8.3. Application of this definition shows that the computed acidity in mgL -1 as CaCO 3 (based on pH and analytical concentrations of dissolved Fe II , Fe III , Mn, and Al in mgL -1 ):acidity calculated =50{1000(10 -pH )+[2(Fe II )+3(Fe III )]/56+2(Mn) /55+3(Al)/27}underestimates contributions from HSO 4 - and H + , but overestimates the acidity due to Fe 3+ and Al 3+ . However, these errors tend to approximately cancel each other. It is demonstrated that 'net alkalinity' is a valid mathematical construction based on theoretical definitions of alkalinity and acidity. Further, it is shown that, for most mine-drainage solutions, a useful net alkalinity value can be derived from: (1) alkalinity and acidity values based on aqueous speciation (2) measured alkalinity minus calculated acidity, or (3) taking the negative of the
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Net alkalinity and net acidity 1: Theoretical considerations
Kirby, C.S.; Cravotta, C.A.
2005-01-01
Net acidity and net alkalinity are widely used, poorly defined, and commonly misunderstood parameters for the characterization of mine drainage. The authors explain theoretical expressions of 3 types of alkalinity (caustic, phenolphthalein, and total) and acidity (mineral, CO2, and total). Except for rarely-invoked negative alkalinity, theoretically defined total alkalinity is closely analogous to measured alkalinity and presents few practical interpretation problems. Theoretically defined "CO 2-acidity" is closely related to most standard titration methods with an endpoint pH of 8.3 used for determining acidity in mine drainage, but it is unfortunately named because CO2 is intentionally driven off during titration of mine-drainage samples. Using the proton condition/mass- action approach and employing graphs to illustrate speciation with changes in pH, the authors explore the concept of principal components and how to assign acidity contributions to aqueous species commonly present in mine drainage. Acidity is defined in mine drainage based on aqueous speciation at the sample pH and on the capacity of these species to undergo hydrolysis to pH 8.3. Application of this definition shows that the computed acidity in mg L -1 as CaCO3 (based on pH and analytical concentrations of dissolved FeII, FeIII, Mn, and Al in mg L -1):aciditycalculated=50{1000(10-pH)+[2(FeII)+3(FeIII)]/56+2(Mn)/ 55+3(Al)/27}underestimates contributions from HSO4- and H+, but overestimates the acidity due to Fe3+ and Al3+. However, these errors tend to approximately cancel each other. It is demonstrated that "net alkalinity" is a valid mathematical construction based on theoretical definitions of alkalinity and acidity. Further, it is shown that, for most mine-drainage solutions, a useful net alkalinity value can be derived from: (1) alkalinity and acidity values based on aqueous speciation, (2) measured alkalinity minus calculated acidity, or (3) taking the negative of the value obtained in a
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Proof Nets for Lambek Calculus
Roorda, Dirk
1992-01-01
The proof nets of linear logic are adapted to the non-commutative Lambek calculus. A different criterion for soundness of proof nets is given, which gives rise to new algorithms for proof search. The order sensitiveness of the Lambek calculus is reflected by the planarity condition on proof nets;
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Properties of porous netted materials
International Nuclear Information System (INIS)
Daragan, V.D.; Drozdov, B.G.; Kotov, A.Yu.; Mel'nikov, G.N.; Pustogarov, A.V.
1987-01-01
Hydraulic and strength characteristics, efficient heat conduction and inner heat exchange coefficient are experimentally studied for porous netted materials on the base of the brass nets as dependent on porosity, cell size and method of net laying. Results of the studies are presented. It is shown that due to anisotropy of the material properties the hydraulic resistance in the direction parallel to the nets plane is 1.3-1.6 times higher than in the perpendicular one. Values of the effective heat conduction in the direction perpendicular to the nets plane at Π>0.45 agree with the data from literature, at Π<0.45 a deviation from the calculated values is marked in the direction of the heat conduction decrease
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Advanced server virtualization VMware and Microsoft platforms in the virtual data center
Marshall, David; McCrory, Dave
2006-01-01
Executives of IT organizations are compelled to quickly implement server virtualization solutions because of significant cost savings. However, most IT professionals tasked with deploying virtualization solutions have little or no experience with the technology. This creates a high demand for information on virtualization and how to properly implement it in a datacenter. Advanced Server Virtualization: VMware® and Microsoft® Platforms in the Virtual Data Center focuses on the core knowledge needed to evaluate, implement, and maintain an environment that is using server virtualization. This boo
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DEFF Research Database (Denmark)
Ernst, Erik; Ostermann, Klaus; Cook, William Randall
2006-01-01
Virtual classes are class-valued attributes of objects. Like virtual methods, virtual classes are defined in an object's class and may be redefined within subclasses. They resemble inner classes, which are also defined within a class, but virtual classes are accessed through object instances...... model for virtual classes has been a long-standing open question. This paper presents a virtual class calculus, vc, that captures the essence of virtual classes in these full-fledged programming languages. The key contributions of the paper are a formalization of the dynamic and static semantics of vc...
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Oki, T.; Kondo, T.; Pokhrel, Y. N.; Hanasaki, N.
2011-12-01
The original concept of virtual water trade was invented to illustrate how much water demand can be reduced by importing food products (Allan 1996), and expanded for meat products and industrial products (Oki and Kanae, 2004). However, there was a confusion between "virtual trade of water" (original) and "trade of virtual water" (misinterpretation but widely accepted), and "virtual water" has been recognized as how much water was used to produce the commodity. Then, the concept has some analogy to carbon footprint (CFP) which is an indicator of total emission of greenhouse gases, and nowadays called water footprint (WFP, Hoekstra, 2004). However, WFP itself is just an inventory of water usages under the framework of life cycle assessment (LCA), and the volume of WFP does not necessary reflect the environmental impacts of water usages because consumptive water use of 100 liter from ground water in arid regions just before rainy season would have more environmental impacts than consumptive water use of 100 liter from rain water in humid regions during snow melt season. In the case of CFP, the emissions of five greenhouse gases except for CO2 were converted into CO2 equivalent volumes by considering the sensitivity for the global warming potential, and summed up into CFP. Here, we propose a new idea objectively determining the weights (characterization factors) for blue water usages, such as from river and ground water, to be converted into green water equivalent in each region and time. The weights are inversely proportional to the area required to obtain the same amount of green water, and water balance model can provide the basic information. The new concept was applied to the WFP of Japan through the imports of major crops. As an inventory, WFP was 15.5 km3/y of rain water, 2.2 km3/y of river water, and 2.0 km3/y of non-renewable and non-local water (NRNL water) for year 2000, however, considering the proposed characterization factors in each region (0.5 x 0
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Understanding Net Zero Energy Buildings
DEFF Research Database (Denmark)
Salom, Jaume; Widén, Joakim; Candanedo, José
2011-01-01
Although several alternative definitions exist, a Net-Zero Energy Building (Net ZEB) can be succinctly described as a grid-connected building that generates as much energy as it uses over a year. The “net-zero” balance is attained by applying energy conservation and efficiency measures...... and by incorporating renewable energy systems. While based on annual balances, a complete description of a Net ZEB requires examining the system at smaller time-scales. This assessment should address: (a) the relationship between power generation and building loads and (b) the resulting interaction with the power grid...
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The Virtual Tablet: Virtual Reality as a Control System
Chronister, Andrew
2016-01-01
In the field of human-computer interaction, Augmented Reality (AR) and Virtual Reality (VR) have been rapidly growing areas of interest and concerted development effort thanks to both private and public research. At NASA, a number of groups have explored the possibilities afforded by AR and VR technology, among which is the IT Advanced Concepts Lab (ITACL). Within ITACL, the AVR (Augmented/Virtual Reality) Lab focuses on VR technology specifically for its use in command and control. Previous work in the AVR lab includes the Natural User Interface (NUI) project and the Virtual Control Panel (VCP) project, which created virtual three-dimensional interfaces that users could interact with while wearing a VR headset thanks to body- and hand-tracking technology. The Virtual Tablet (VT) project attempts to improve on these previous efforts by incorporating a physical surrogate which is mirrored in the virtual environment, mitigating issues with difficulty of visually determining the interface location and lack of tactile feedback discovered in the development of previous efforts. The physical surrogate takes the form of a handheld sheet of acrylic glass with several infrared-range reflective markers and a sensor package attached. Using the sensor package to track orientation and a motion-capture system to track the marker positions, a model of the surrogate is placed in the virtual environment at a position which corresponds with the real-world location relative to the user's VR Head Mounted Display (HMD). A set of control mechanisms is then projected onto the surface of the surrogate such that to the user, immersed in VR, the control interface appears to be attached to the object they are holding. The VT project was taken from an early stage where the sensor package, motion-capture system, and physical surrogate had been constructed or tested individually but not yet combined or incorporated into the virtual environment. My contribution was to combine the pieces of
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Water Accounting Plus for Water Resources Reporting and River Basin Planning
Karimi, P.
2014-01-01
This thesis introduces Water Accounting Plus (WA+), which is a new framework designed to provide explicit spatial information on water depletion and net withdrawal processes in complex river basins. WA+ is a simple, yet comprehensive and understandable water accounting framework that provides a
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Global Distribution of Net Electron Acceptance in Subseafloor Sediment
Fulfer, V. M.; Pockalny, R. A.; D'Hondt, S.
2017-12-01
We quantified the global distribution of net electron acceptance rates (e-/m2/year) in subseafloor sediment (>1.5 meters below seafloor [mbsf]) using (i) a modified version of the chemical-reaction-rate algorithm by Wang et al. (2008), (ii) physical properties and dissolved oxygen and sulfate data from interstitial waters of sediment cores collected by the Ocean Drilling Program, Integrated Ocean Drilling Program, International Ocean Discovery Program, and U.S. coring expeditions, and (iii) correlation of net electron acceptance rates to global oceanographic properties. Calculated net rates vary from 4.8 x 1019 e-/m2/year for slowly accumulating abyssal clay to 1.2 x 1023 e-/m2/year for regions of high sedimentation rate. Net electron acceptance rate correlates strongly with mean sedimentation rate. Where sedimentation rate is very low (e.g., 1 m/Myr), dissolved oxygen penetrates more than 70 mbsf and is the primary terminal electron acceptor. Where sedimentation rate is moderate (e.g., 3 to 60 m/Myr), dissolved sulfate penetrates as far as 700 mbsf and is the principal terminal electron acceptor. Where sedimentation rate is high (e.g., > 60 m/Myr), dissolved sulfate penetrates only meters, but is the principal terminal electron acceptor in subseafloor sediment to the depth of sulfate penetration. Because microbial metabolism continues at greater depths than the depth of sulfate penetration in fast-accumulating sediment, complete quantification of subseafloor metabolic rates will require consideration of other chemical species.
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History-dependent stochastic Petri nets
Schonenberg, H.; Sidorova, N.; Aalst, van der W.M.P.; Hee, van K.M.; Pnueli, A.; Virbitskaite, I.; Voronkov, A.
2010-01-01
Stochastic Petri Nets are a useful and well-known tool for performance analysis. However, an implicit assumption in the different types of Stochastic Petri Nets is the Markov property. It is assumed that a choice in the Petri net only depends on the current state and not on earlier choices. For many
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DEFF Research Database (Denmark)
Svejvig, Per; Commisso, Trine Hald
2012-01-01
that the best practice knowledge has not permeated sufficiently to the practice. Furthermore, the appropriate application of information and communication technology (ICT) remains a big challenge, and finally project managers are not sufficiently trained in organizing and conducting virtual projects....... The overall implications for research and practice are to acknowledge virtual project management as very different to traditional project management and to address this difference.......Virtual projects are common with global competition, market development, and not least the financial crisis forcing organizations to reduce their costs drastically. Organizations therefore have to place high importance on ways to carry out virtual projects and consider appropriate practices...
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Water security of nations: how international trade affects national water scarity and dependency
Hoekstra, Arjen Ysbert; Jones, J. Anthony A.; Vardanian, Trahel G.; Hakopian, Christina
2009-01-01
Import of water in virtual form, i.e. in the form of agricultural and industrial commodities, can be an effective means for water-scarce countries to preserve their domestic water resources. On the other hand, export of water-intensive commodities will increase the use and thus the scarcity of water
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MacDonald, Matthew; Freeman, Adam; Szpuszta, Mario; Agarwal, Vidya Vrat
2010-01-01
ASP.NET 4 is the latest version of Microsoft's revolutionary ASP.NET technology. It is the principal standard for creating dynamic web pages on the Windows platform. Pro ASP.NET 4 in VB 2010 raises the bar for high-quality, practical advice on learning and deploying Microsoft's dynamic web solution. This new edition is updated with everything you need to come to grips with the latest version of ASP.NET, including coverage of ASP.NET MVC, ASP.NET AJAX 4, ASP.NET Dynamic Data, and Silverlight 3. Seasoned .NET professionals Matthew MacDonald and Mario Szpuszta explain how you can get the most fro
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Energy Technology Data Exchange (ETDEWEB)
NONE
1999-03-01
Under the hydrogen-utilizing international clean energy system technology project WE-NET (World Energy NET Work), researches were conducted aiming at the establishment of a hydrogen production technology through electrolysis of polymer electrolyte solution. In fiscal 1998, element technologies were developed for the development of high-efficiency/large-capacity water electrolyzing plants using electrodeless deposition and hot pressing, research and investigation of optimum operating conditions were conducted, and a service plant conceptual design and a polymer electrolytic membrane were developed. In addition, literature was searched for the current state of ion exchange membranes and water electrolysis, both indispensable for the hydrogen production technology discussed in this paper. In the field of lamination of large cells (electrode surface:2500cm{sup 2}), an excellent energy efficiency level exceeding 90% set as the target for a large laminated cell performance test was achieved - 92.6% by electrodeless deposition and 94.4% by hot pressing. As for polymer membranes capable of resisting high temperatures, a membrane with an ionic conductivity of 0.066S/cm at 200 degrees C was newly developed. (NEDO)
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Lee, Jae Seong; Kang, Dong-Jin; Hineva, Elitsa; Slabakova, Violeta; Todorova, Valentina; Park, Jiyoung; Cho, Jin-Hyung
2017-06-01
We measured the community-scale metabolism of seagrass meadows in Bulgaria (Byala [BY]) and Korea (Hoopo Bay [HP]) to understand their ecosystem function in coastal waters. A noninvasive in situ eddy covariance technique was applied to estimate net O2 flux in the seagrass meadows. From the high-quality and high-resolution time series O2 data acquired over > 24 h, the O2 flux driven by turbulence was extracted at 15-min intervals. The spectrum analysis of vertical flow velocity and O2 concentration clearly showed well-developed turbulence characteristics in the inertial subrange region. The hourly averaged net O2 fluxes per day ranged from -474 to 326 mmol O2 m-2 d-1 (-19 ± 41 mmol O2 m-2 d-1) at BY and from -74 to 482 mmol O2 m-2 d-1 (31 ± 17 mmol O2 m-2 d-1) at HP. The net O2 production rapidly responded to photosynthetically available radiation (PAR) and showed a good relationship between production and irradiance (P-I curve). The hysteresis pattern of P-I relationships during daytime also suggested increasing heterotrophic respiration in the afternoon. With the flow velocity between 3.30 and 6.70 cm s-1, the community metabolism during daytime and nighttime was significantly increased by 20 times and 5 times, respectively. The local hydrodynamic characteristics may be vital to determining the efficiency of community photosynthesis. The net ecosystem metabolism at BY was estimated to be -17 mmol O2 m-2 d-1, which was assessed as heterotrophy. However, that at HP was 36 mmol O2 m-2 d-1, which suggested an autotrophic state.
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NASA Net Zero Energy Buildings Roadmap
Energy Technology Data Exchange (ETDEWEB)
Pless, S.; Scheib, J.; Torcellini, P.; Hendron, B.; Slovensky, M.
2014-10-01
In preparation for the time-phased net zero energy requirement for new federal buildings starting in 2020, set forth in Executive Order 13514, NASA requested that the National Renewable Energy Laboratory (NREL) to develop a roadmap for NASA's compliance. NASA detailed a Statement of Work that requested information on strategic, organizational, and tactical aspects of net zero energy buildings. In response, this document presents a high-level approach to net zero energy planning, design, construction, and operations, based on NREL's first-hand experience procuring net zero energy construction, and based on NREL and other industry research on net zero energy feasibility. The strategic approach to net zero energy starts with an interpretation of the executive order language relating to net zero energy. Specifically, this roadmap defines a net zero energy acquisition process as one that sets an aggressive energy use intensity goal for the building in project planning, meets the reduced demand goal through energy efficiency strategies and technologies, then adds renewable energy in a prioritized manner, using building-associated, emission- free sources first, to offset the annual energy use required at the building; the net zero energy process extends through the life of the building, requiring a balance of energy use and production in each calendar year.
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DEFF Research Database (Denmark)
Bjørn, Pernille
2005-01-01
Investigating virtual team collaboration in industry using grounded theory this paper presents the in-dept analysis of empirical work conducted in a global organization of 100.000 employees where a global virtual team with participants from Sweden, United Kingdom, Canada, and North America were...... studied. The research question investigated is how collaboration is negotiated within virtual teams? This paper presents findings concerning how collaboration is negotiated within a virtual team and elaborate the difficulties due to invisible articulation work and managing multiple communities...... in transforming the virtual team into a community. It is argued that translucence in communication structures within the virtual team and between team and management is essential for engaging in a positive transformation process of trustworthiness supporting the team becoming a community, managing the immanent...
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DEFF Research Database (Denmark)
Ess, Charles; Thorseth, May
2011-01-01
We collect diverse philosophical analyses of the issues and problems clustering around trust online with specific attention to establishing trust in virtual environments. The book moves forward important discussions of how virtual worlds and virtuality are to be defined and understood; the role o...... by virtuality, such as virtual child pornography. The introduction further develops a philosophical anthropology, rooted in Kantian ethics, phenomenology, virtue ethics, and feminist perspectives, that grounds a specific approach to ethical issues in virtual environments....
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Regional water footprint and water management: the case of Madrid region (Spain)
Soler Rovira, José; Arroyo Sanz, Juan Manuel; Conde Marcos, Hugo; Sanz Zudaire, Carlos; Mesa Moreno, Alfredo; Gil Pascual, Sergio
2010-01-01
Water resources and water footprint of the production and consumption in Madrid region were estimated, considering blue water (water resources), green water (soil moisture), grey water (polluted water) and virtual water (water trade in products imported and exported in the region). Water resources in Madrid relay mainly in surface waters and rainfall, so the periodic occurrence of meteorological droughts implies the scarcity of water supply. The main users of blue water are households, munici...
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Flanders, Jon
2008-01-01
RESTful .NET is the first book that teaches Windows developers to build RESTful web services using the latest Microsoft tools. Written by Windows Communication Foundation (WFC) expert Jon Flanders, this hands-on tutorial demonstrates how you can use WCF and other components of the .NET 3.5 Framework to build, deploy and use REST-based web services in a variety of application scenarios. RESTful architecture offers a simpler approach to building web services than SOAP, SOA, and the cumbersome WS- stack. And WCF has proven to be a flexible technology for building distributed systems not necessa
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Energy Technology Data Exchange (ETDEWEB)
2016-09-01
The technology necessary to build net zero energy buildings (NZEBs) is ready and available today, however, building to net zero energy performance levels can be challenging. Energy efficiency measures, onsite energy generation resources, load matching and grid interaction, climatic factors, and local policies vary from location to location and require unique methods of constructing NZEBs. It is recommended that Components start looking into how to construct and operate NZEBs now as there is a learning curve to net zero construction and FY 2020 is just around the corner.
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DEFF Research Database (Denmark)
Marszal, Anna Joanna; Bourrelle, Julien S.; Gustavsen, Arild
2010-01-01
and identify possible renewable energy supply options which may be considered in calculations. Finally, the gap between the methodology proposed by each organisation and their respective national building code is assessed; providing an overview of the possible changes building codes will need to undergo......The international cooperation project IEA SHC Task 40 / ECBCS Annex 52 “Towards Net Zero Energy Solar Buildings”, attempts to develop a common understanding and to set up the basis for an international definition framework of Net Zero Energy Buildings (Net ZEBs). The understanding of such buildings...
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Ritchie, Stephen D
2011-01-01
Pro .NET Best Practices is a practical reference to the best practices that you can apply to your .NET projects today. You will learn standards, techniques, and conventions that are sharply focused, realistic and helpful for achieving results, steering clear of unproven, idealistic, and impractical recommendations. Pro .NET Best Practices covers a broad range of practices and principles that development experts agree are the right ways to develop software, which includes continuous integration, automated testing, automated deployment, and code analysis. Whether the solution is from a free and
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Evolution-based Virtual Content Insertion with Visually Virtual Interactions in Videos
Chang, Chia-Hu; Wu, Ja-Ling
With the development of content-based multimedia analysis, virtual content insertion has been widely used and studied for video enrichment and multimedia advertising. However, how to automatically insert a user-selected virtual content into personal videos in a less-intrusive manner, with an attractive representation, is a challenging problem. In this chapter, we present an evolution-based virtual content insertion system which can insert virtual contents into videos with evolved animations according to predefined behaviors emulating the characteristics of evolutionary biology. The videos are considered not only as carriers of message conveyed by the virtual content but also as the environment in which the lifelike virtual contents live. Thus, the inserted virtual content will be affected by the videos to trigger a series of artificial evolutions and evolve its appearances and behaviors while interacting with video contents. By inserting virtual contents into videos through the system, users can easily create entertaining storylines and turn their personal videos into visually appealing ones. In addition, it would bring a new opportunity to increase the advertising revenue for video assets of the media industry and online video-sharing websites.
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2014-01-01
Background Electric nets (e-nets) are used to analyse the flight behaviour of insects and have been used extensively to study the host-oriented flight of tsetse flies. Recently we adapted this tool to analyse the oviposition behaviour of gravid malaria vectors, Anopheles gambiae s.s., orienting towards aquatic habitats and traps by surrounding an artificial pond with e-nets and collecting electrocuted mosquitoes on sticky boards on the ground next to the nets. Here we study whether e-nets themselves affect the responses of gravid An. gambiae s.s.. Methods Dual-choice experiments were carried out in 80 m2 screened semi-field systems where 200 gravid An. gambiae s.s. were released each night for 12 nights per experiment. The numbers of mosquito landing on or approaching an oviposition site were studied by adding detergent to the water in an artificial pond or surrounding the pond with a square of e-nets. We also assessed whether the supporting framework of the nets or the sticky boards used to retain electrocuted mosquitoes influenced the catch. Results Two similar detergent treated ponds presented in choice tests caught an equal proportion of the mosquitoes released, whereas a pond surrounded by e-nets caught a higher proportion than an open pond (odds ratio (OR) 1.7, 95% confidence interval (CI) 1.1 - 2.7; p electric nets and the yellow boards on the approach of gravid females towards a pond suggests that the tower-like construction of the square of electric nets did not restrict the approach of females but the yellow sticky boards on the ground attract gravid females to a source of water (OR 2.7 95% CI 1.7 – 4.3; p trapping efficiency of the electric nets is increased when large yellow sticky boards are placed on the ground next to the e-nets to collect electrocuted mosquitoes, possibly because of increased visual contrast to the aquatic habitat. It is therefore important when comparing two treatments that the same trapping device is used in both. The
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ASP.NET web API build RESTful web applications and services on the .NET framework
Kanjilal, Joydip
2013-01-01
This book is a step-by-step, practical tutorial with a simple approach to help you build RESTful web applications and services on the .NET framework quickly and efficiently.This book is for ASP.NET web developers who want to explore REST-based services with C# 5. This book contains many real-world code examples with explanations whenever necessary. Some experience with C# and ASP.NET 4 is expected.
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Theft of Virtual Property — Towards Security Requirements for Virtual Worlds
Beyer, Anja
The article is focused to introduce the topic of information technology security for Virtual Worlds to a security experts’ audience. Virtual Worlds are Web 2.0 applications where the users cruise through the world with their individually shaped avatars to find either amusement, challenges or the next best business deal. People do invest a lot of time but beyond they invest in buying virtual assets like fantasy witcheries, wepaons, armour, houses, clothes,...etc with the power of real world money. Although it is called “virtual” (which is often put on the same level as “not existent”) there is a real value behind it. In November 2007 dutch police arrested a seventeen years old teenager who was suspicted to have stolen virtual items in a Virtual World called Habbo Hotel [Reuters07]. In order to successfully provide security mechanisms into Virtual Worlds it is necessarry to fully understand the domain for which the security mechansims are defined. As Virtual Worlds must be clasified into the domain of Social Software the article starts with an overview of how to understand Web 2.0 and gives a short introduction to Virtual Worlds. The article then provides a consideration of assets of Virtual Worlds participants, describes how these assets can be threatened and gives an overview of appopriate security requirements and completes with an outlook of possible countermeasures.
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Interaction with virtual crowd in Immersive and semi‐Immersive Virtual Reality systems
Kyriakou, Marios; Pan, Xueni; Chrysanthou, Yiorgos
2016-01-01
This study examines attributes of virtual human behavior that may increase the plausibility of a simulated crowd and affect the user's experience in Virtual Reality. Purpose-developed experiments in both Immersive and semi-Immersive Virtual Reality systems queried the impact of collision and basic interaction between real-users and the virtual crowd and their effect on the apparent realism and ease of navigation within Virtual Reality (VR). Participants' behavior and subjective measurements i...
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Analysis of Blue and Green Water Consumption at the Irrigation District Scale
Directory of Open Access Journals (Sweden)
Jing Liu
2018-01-01
Full Text Available The concepts of virtual water and water footprint bring a new perspective for water management. Previous studies mainly focus on one type of water and the relationship between water footprint and water availability. In this study, three indicators were proposed to show water consumption and the influences of virtual water flows at the Hetao irrigation district, China, during 2001–2010, considering both blue and green water. Results indicate that the ratio of blue water footprint and blue water availability was 0.642 in 2010 and the value for green water was 0.148, coefficients on contribution of regional production on consumption in other areas were about 0.9, and coefficients on influences of trades from other regions to the district on regional water consumption were 0.528 (blue water and 0.433 (green water, respectively. Government should promote water pricing policies that can encourage the adoption of irrigation technologies and water-saving practices. Besides, the adjustment of the crop sowing date or the cultivation of new varieties may be helpful in using more rainfall. Lastly, a compensation mechanism for virtual water export should be built in the future, and virtual water importing can be advocated. Before actions are taken, the possible influences and related constraints should be considered.
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Directory of Open Access Journals (Sweden)
Anand K. Inamdar
2015-08-01
Full Text Available The Earth’s surface net radiation controls the energy and water exchanges between the Earth’s surface and the atmosphere, and can be derived from satellite observations. The ability to monitor the net surface radiation over large areas at high spatial and temporal resolution is essential for many applications, such as weather forecasting, short-term climate prediction or water resources management. The objective of this paper is to derive the net surface radiation in the shortwave domain at high temporal (half-hourly and spatial resolution (~1 km using visible imagery from Geostationary Operational Environmental Satellite (GOES. The retrieval algorithm represents an adaptation to GOES data of a standard algorithm initially developed for the NASA-operated Clouds and Earth’s Radiant Energy System (CERES scanner. The methodology relies on: (1 the estimation of top of atmosphere shortwave radiation from GOES spectral measurements; and (2 the calculation of net surface shortwave (SW radiation accounting for atmospheric effects. Comparison of GOES-retrieved net surface shortwave radiation with ground-measurements at the National Oceanic and Atmospheric Administration’s (NOAA Surface Radiation (SURFRAD stations yields very good agreement with average bias lower than 5 W·m−2 and root mean square difference around 70 W·m−2. The algorithm performance is usually higher over areas characterized by low spatial variability in term of land cover type and surface biophysical properties. The technique does not involve retrieval and assessment of cloud properties and can be easily adapted to other meteorological satellites around the globe.
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Translating Colored Control Flow Nets into Readable Java via Annotated Java Workflow Nets
DEFF Research Database (Denmark)
Lassen, Kristian Bisgaard; Tjell, Simon
2007-01-01
In this paper, we present a method for developing Java applications from Colored Control Flow Nets (CCFNs), which is a special kind of Colored Petri Nets (CPNs) that we introduce. CCFN makes an explicit distinction between the representation of: The system, the environment of the system, and the ......In this paper, we present a method for developing Java applications from Colored Control Flow Nets (CCFNs), which is a special kind of Colored Petri Nets (CPNs) that we introduce. CCFN makes an explicit distinction between the representation of: The system, the environment of the system......, and the interface between the system and the environment. Our translation maps CCFNs into Anno- tated Java Workflow Nets (AJWNs) as an intermediate step, and these AJWNs are finally mapped to Java. CCFN is intended to enforce the modeler to describe the system in an imperative manner which makes the subsequent...... translation to Java easier to define. The translation to Java preserves data dependencies and control-flow aspects of the source CCFN. This paper contributes to the model-driven software development paradigm, by showing how to model a system, environment, and their interface, as a CCFN and presenting a fully...
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International Nuclear Information System (INIS)
Kustas, W.P.; Prueger, J.H.; Hipps, L.E.; Hatfield, J.L.; Meek, D.
1998-01-01
Studies of surface energy and water balance generally require an accurate estimate of net radiation and its spatial distribution. A project quantifying both short term and seasonal water use of shrub and grass vegetation in the Jornada Experimental Range in New Mexico prompted a study to compare net radiation observations using two types of net radiometers currently being used in research. A set of 12 REBS net radiometers were compared with each other and one Swissteco, over wet and dry surfaces in an arid landscape under clear skies. The set of REBS exhibited significant differences in output over both surfaces. However, they could be cross calibrated to yield values within 10 W m −2 , on average. There was also a significant bias between the REBS and Swissteco over a dry surface, but not over a wet one. The two makes of instrument could be made to agree under the dry conditions by using regression or autoregression techniques. However, the resulting equations would induce bias for the wet surface condition. Thus, it is not possible to cross calibrate these two makes of radiometer over the range of environmental conditions observed. This result indicates that determination of spatial distribution of net radiation over a variable surface should be made with identical instruments which have been cross calibrated. The need still exists for development of a radiometer and calibration procedures which will produce accurate and consistent measurements over a range of surface conditions. (author)
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Feasibility of Achieving a Zero-Net-Energy, Zero-Net-Cost Homes
Energy Technology Data Exchange (ETDEWEB)
Al-Beaini, S.; Borgeson, S.; Coffery, B.; Gregory, D.; Konis, K.; Scown, C.; Simjanovic, J.; Stanley, J.; Strogen, B.; Walker, I.
2009-09-01
A green building competition, to be known as the Energy Free Home Challenge (EFHC), is scheduled to be opened to teams around the world in 2010. This competition will encourage both design innovation and cost reduction, by requiring design entries to meet 'zero net energy' and 'zero net cost' criteria. For the purposes of this competition, a 'zero net energy' home produces at least as much energy as it purchases over the course of a year, regardless of the time and form of the energy (e.g., electricity, heat, or fuel) consumed or produced. A 'zero net cost' home is no more expensive than a traditional home of comparable size and comfort, when evaluated over the course of a 30-year mortgage. In other words, the 'green premium' must have a payback period less than 30 years, based on the value of energy saved. The overarching goal of the competition is to develop affordable, high-performance homes that can be mass-produced at a large scale, and are able to meet occupant needs in harsh climates (as can be found where the competition will be held in Illinois). This report outlines the goals of the competition, and gauges their feasibility using both modeling results and published data. To ensure that the established rules are challenging, yet reasonable, this report seeks to refine the competition goals after exploring their feasibility through case studies, cost projections, and energy modeling. The authors of this report conducted a survey of the most progressive home energy-efficiency practices expected to appear in competition design submittals. In Appendix A, a summary can be found of recent projects throughout the United States, Canada, Germany, Switzerland, Sweden and Japan, where some of the most progressive technologies have been implemented. As with past energy efficient home projects, EFHC competitors will incorporate a multitude of energy efficiency measures into their home designs. The authors believe that
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DEFF Research Database (Denmark)
Gürsimsek, Remzi Ates
2014-01-01
The online social platforms known as virtual worlds present their users various affordances for avatar based co-presence, social interaction and provide tools for collaborative content creation, including objects, textures and animations. The users of these worlds navigate their avatars as personal...... the audio-visual characteristics of designing in multi-user virtual environments generate experiential, interpersonal and textual meaning potentials....... mediators in 3D virtual space to collaborate and co-design the digital content. These co-designers are also the residents of these worlds, as they socialize by building inworld friendships. This article presents a social semiotic analysis of the three-dimensional virtual places and artifacts in the virtual...
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Liberty, Jesse
2009-01-01
Bestselling author Jesse Liberty and industry expert Alex Horovitz uncover the common threads that unite the .NET 3.5 technologies, so you can benefit from the best practices and architectural patterns baked into the new Microsoft frameworks. The book offers a Grand Tour" of .NET 3.5 that describes how the principal technologies can be used together, with Ajax, to build modern n-tier and service-oriented applications. "
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The vulnerability and resilience of a city's water footprint: The case of Flagstaff, Arizona, USA
Rushforth, Richard R.; Ruddell, Benjamin L.
2016-04-01
Research has yet to operationalize water footprint information for urban water policy and planning to reduce vulnerability and increase resilience to water scarcity. Using a county-level database of the U.S. hydro-economy, NWED, we spatially mapped and analyzed the Water Footprint of Flagstaff, Arizona, a small city. Virtual water inflow and outflow networks were developed using the flow of commodities into and out of the city. The power law distribution of virtual water trade volume between Flagstaff and its county trading partners broke at a spatial distance of roughly 2000 km. Most large trading partners are within this geographical distance, and this distance is an objective definition for Flagstaff's zone of indirect hydro-economic influence—that is, its water resource hinterland. Metrics were developed to measure Flagstaff's reliance on virtual water resources, versus direct use of local physical water resources. Flagstaff's reliance on external water supplies via virtual water trade increases both its hydro-economic resilience and vulnerability to water scarcity. These methods empower city managers to operationalize the city's Water Footprint information to reduce vulnerability, increase resilience, and optimally balance the allocation of local physical water supplies with the outsourcing of some water uses via the virtual water supply chain.
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Server virtualization solutions
Jonasts, Gusts
2012-01-01
Currently in the information technology sector that is responsible for a server infrastructure is a huge development in the field of server virtualization on x86 computer architecture. As a prerequisite for such a virtualization development is growth in server productivity and underutilization of available computing power. Several companies in the market are working on two virtualization architectures – hypervizor and hosting. In this paper several of virtualization products that use host...
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Henriksen, Knud; Sporring, Jon; Hornbæk, Kasper
2004-01-01
Udgivelsesdato: March/April Rotation of three-dimensional objects by a two-dimensional mouse is a typical task in computer-aided design, operation simulations, and desktop virtual reality. The most commonly used rotation technique is a virtual trackball surrounding the object and operated by the mouse pointer. This article reviews and provides a mathematical foundation for virtual trackballs. The first, but still popular, virtual trackball was described by Chen et al. [CHECK END OF SENTENC...
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Interactive Virtual Cinematography
Burelli, Paolo
2012-01-01
A virtual camera represents the point-of-view of the player through which sheperceives the game world and gets feedback on her actions. Thus, the virtualcamera plays a vital role in 3D computer games and aects player experienceand enjoyability in games. Interactive virtual cinematography is the process ofvisualising the content of a virtual environment by positioning and animatingthe virtual camera in the context of interactive applications such as a computergame.Camera placement and animatio...
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Korthauer, L E; Nowak, N T; Frahmand, M; Driscoll, I
2017-01-15
Although effective spatial navigation requires memory for objects and locations, navigating a novel environment may also require considerable executive resources. The present study investigated associations between performance on the virtual Morris Water Task (vMWT), an analog version of a nonhuman spatial navigation task, and neuropsychological tests of executive functioning and spatial performance in 75 healthy young adults. More effective vMWT performance (e.g., lower latency and distance to reach hidden platform, greater distance in goal quadrant on a probe trial, fewer path intersections) was associated with better verbal fluency, set switching, response inhibition, and ability to mentally rotate objects. Findings also support a male advantage in spatial navigation, with sex moderating several associations between vMWT performance and executive abilities. Overall, we report a robust relationship between executive functioning and navigational skill, with some evidence that men and women may differentially recruit cognitive abilities when navigating a novel environment. Copyright © 2016 Elsevier B.V. All rights reserved.
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Net metering: zero electricity bill
International Nuclear Information System (INIS)
Mangi, A.; Khan, Z.
2011-01-01
Worldwide move towards renewable energy sources, environmental concerns and decentralization of the power sector have made net metering an attractive option for power generation at small scale. This paper discusses the net metering, economical issues of renewable sources in Pakistan, technical aspects, installation suitability according to varying terrain, existing utility rules and formulation of legislation for net metering making it economically attractive. (author)
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Isolated core vs. superficial cooling effects on virtual maze navigation.
Payne, Jennifer; Cheung, Stephen S
2007-07-01
Cold impairs cognitive performance and is a common occurrence in many survival situations. Altered behavior patterns due to impaired navigation abilities in cold environments are potential problems in lost-person situations. We investigated the separate effects of low core temperature and superficial cooling on a spatially demanding virtual navigation task. There were 12 healthy men who were passively cooled via 15 degrees C water immersion to a core temperature of 36.0 degrees C, then transferred to a warm (40 degrees C) water bath to eliminate superficial shivering while completing a series of 20 virtual computer mazes. In a control condition, subjects rested in a thermoneutral (approximately 35 degrees C) bath for a time-matched period before being transferred to a warm bath for testing. Superficial cooling and distraction were achieved by whole-body immersion in 35 degree water for a time-matched period, followed by lower leg immersion in 10 degree C water for the duration of the navigational tests. Mean completion time and mean error scores for the mazes were not significantly different (p > 0.05) across the core cooling (16.59 +/- 11.54 s, 0.91 +/- 1.86 errors), control (15.40 +/- 8.85 s, 0.82 +/- 1.76 errors), and superficial cooling (15.19 +/- 7.80 s, 0.77 +/- 1.40 errors) conditions. Separately reducing core temperature or increasing cold sensation in the lower extremities did not influence performance on virtual computer mazes, suggesting that navigation is more resistive to cooling than other, simpler cognitive tasks. Further research is warranted to explore navigational ability at progressively lower core and skin temperatures, and in different populations.
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The Virtual Watershed Observatory: Cyberinfrastructure for Model-Data Integration and Access
Duffy, C.; Leonard, L. N.; Giles, L.; Bhatt, G.; Yu, X.
2011-12-01
The Virtual Watershed Observatory (VWO) is a concept where scientists, water managers, educators and the general public can create a virtual observatory from integrated hydrologic model results, national databases and historical or real-time observations via web services. In this paper, we propose a prototype for automated and virtualized web services software using national data products for climate reanalysis, soils, geology, terrain and land cover. The VWO has the broad purpose of making accessible water resource simulations, real-time data assimilation, calibration and archival at the scale of HUC 12 watersheds (Hydrologic Unit Code) anywhere in the continental US. Our prototype for model-data integration focuses on creating tools for fast data storage from selected national databases, as well as the computational resources necessary for a dynamic, distributed watershed simulation. The paper will describe cyberinfrastructure tools and workflow that attempts to resolve the problem of model-data accessibility and scalability such that individuals, research teams, managers and educators can create a WVO in a desired context. Examples are given for the NSF-funded Shale Hills Critical Zone Observatory and the European Critical Zone Observatories within the SoilTrEC project. In the future implementation of WVO services will benefit from the development of a cloud cyber infrastructure as the prototype evolves to data and model intensive computation for continental scale water resource predictions.
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Jonker, Catholijn; Broekens, Joost; Plaat, Aske
2014-01-01
Virtual Reality is used successfully to treat people for regular phobias. A new challenge is to develop Virtual Reality Exposure Training for social skills. Virtual actors in such systems have to show appropriate social behavior including emotions, gaze, and keeping distance. The behavior must be realistic and real-time. Current approaches consist of four steps: 1) trainee social signal detection, 2) cognitive-affective interpretation, 3) determination of the appropriate bodily responses, and...
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Li, Zhanqing; Leighton, H. G.; Cess, Robert D.
1993-01-01
A parameterization that relates the reflected solar flux at the top of the atmosphere to the net solar flux at the surface in terms of only the column water vapor amount and the solar zenith angle was tested against surface observations. Net surface fluxes deduced from coincidental collocated satellite-measured radiances and from measurements from towers in Boulder during summer and near Saskatoon in winter have mean differences of about 2 W/sq m, regardless of whether the sky is clear or cloudy. Furthermore, comparisons between the net fluxes deduced from the parameterization and from surface measurements showed equally good agreement when the data were partitioned into morning and afternoon observations. This is in contrast to results from an empirical clear-sky algorithm that is unable to account adequately for the effects of clouds and that shows, at Boulder, a distinct morning to afternoon variation, which is presumably due to the predominance of different cloud types throughout the day. It is also demonstrated that the parameterization may be applied to irradiances at the top of the atmosphere that have been temporally averaged by using the temporally averaged column water vapor amount and the temporally averaged cosine of the solar zenith angle. The good agreement between the results of the parameterization and surface measurements suggests that the algorithm is a useful tool for a variety of climate studies.
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Evapotranspiration (ET) is often estimated with the Penman-Monteith (P-M) equation. Net radiation (Rn) is a major component of the surface energy balance and an input to the P-M equation, but it is challenging and expensive to measure accurately. For these reasons, most weather stations do not inclu...
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Chiang, Vico Chung-Lim; Lo, King-Hung; Choi, Kup-Sze
2017-10-01
To investigate the feasibility of using a virtual rehabilitation system with intuitive user interface and force feedback to improve the skills in activities of daily living (ADL). A virtual training system equipped with haptic devices was developed for the rehabilitation of three ADL tasks - door unlocking, water pouring and meat cutting. Twenty subjects with upper limb disabilities, supervised by two occupational therapists, received a four-session training using the system. The task completion time and the amount of water poured into a virtual glass were recorded. The performance of the three tasks in reality was assessed before and after the virtual training. Feedback of the participants was collected with questionnaires after the study. The completion time of the virtual tasks decreased during the training (p water successfully poured increased (p = 0.051). The score of the Borg scale of perceived exertion was 1.05 (SD = 1.85; 95% CI = 0.18-1.92) and that of the task specific feedback questionnaire was 31 (SD = 4.85; 95% CI = 28.66-33.34). The feedback of the therapists suggested a positive rehabilitation effect. The participants had positive perception towards the system. The system can potentially be used as a tool to complement conventional rehabilitation approaches of ADL. Implications for rehabilitation Rehabilitation of activities of daily living can be facilitated using computer-assisted approaches. The existing approaches focus on cognitive training rather than the manual skills. A virtual training system with intuitive user interface and force feedback was designed to improve the learning of the manual skills. The study shows that system could be used as a training tool to complement conventional rehabilitation approaches.
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DEFF Research Database (Denmark)
de Souza e Silva, Adriana Araujo; Gordon, Eric
Provides an introduction to the new theory of Net Locality and the profound effect on individuals and societies when everything is located or locatable. Describes net locality as an emerging form of location awareness central to all aspects of digital media, from mobile phones, to Google Maps......, to location-based social networks and games, such as Foursquare and facebook. Warns of the threats these technologies, such as data surveillance, present to our sense of privacy, while also outlining the opportunities for pro-social developments. Provides a theory of the web in the context of the history...... of emerging technologies, from GeoCities to GPS, Wi-Fi, Wiki Me, and Google Android....
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Construction of monophase nets
International Nuclear Information System (INIS)
Suarez A, Jose Antonio
1996-01-01
The paper refers to the use of monophase loads in commercial residential urbanizations and in small industries, for this reason it is considered unnecessary the construction of three-phase nets. The author makes a historical recount of these nets in Bogota, his capacities, uses and energy savings
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Virtual Beach: Decision Support Tools for Beach Pathogen Prediction
The Virtual Beach Managers Tool (VB) is decision-making software developed to help local beach managers make decisions as to when beaches should be closed due to predicted high levels of water borne pathogens. The tool is being developed under the umbrella of EPA's Advanced Monit...
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Beckhaus, Steffi
Virtual Reality aims at creating an artificial environment that can be perceived as a substitute to a real setting. Much effort in research and development goes into the creation of virtual environments that in their majority are perceivable only by eyes and hands. The multisensory nature of our perception, however, allows and, arguably, also expects more than that. As long as we are not able to simulate and deliver a fully sensory believable virtual environment to a user, we could make use of the fully sensory, multi-modal nature of real objects to fill in for this deficiency. The idea is to purposefully integrate real artifacts into the application and interaction, instead of dismissing anything real as hindering the virtual experience. The term virtual reality - denoting the goal, not the technology - shifts from a core virtual reality to an “enriched” reality, technologically encompassing both the computer generated and the real, physical artifacts. Together, either simultaneously or in a hybrid way, real and virtual jointly provide stimuli that are perceived by users through their senses and are later formed into an experience by the user's mind.
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Terzopoulos, Demetri; Qureshi, Faisal Z.
Computer vision and sensor networks researchers are increasingly motivated to investigate complex multi-camera sensing and control issues that arise in the automatic visual surveillance of extensive, highly populated public spaces such as airports and train stations. However, they often encounter serious impediments to deploying and experimenting with large-scale physical camera networks in such real-world environments. We propose an alternative approach called "Virtual Vision", which facilitates this type of research through the virtual reality simulation of populated urban spaces, camera sensor networks, and computer vision on commodity computers. We demonstrate the usefulness of our approach by developing two highly automated surveillance systems comprising passive and active pan/tilt/zoom cameras that are deployed in a virtual train station environment populated by autonomous, lifelike virtual pedestrians. The easily reconfigurable virtual cameras distributed in this environment generate synthetic video feeds that emulate those acquired by real surveillance cameras monitoring public spaces. The novel multi-camera control strategies that we describe enable the cameras to collaborate in persistently observing pedestrians of interest and in acquiring close-up videos of pedestrians in designated areas.
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Spring hydrology determines summer net carbon uptake in northern ecosystems
International Nuclear Information System (INIS)
Yi, Yonghong; Kimball, John S; Reichle, Rolf H
2014-01-01
Increased photosynthetic activity and enhanced seasonal CO 2 exchange of northern ecosystems have been observed from a variety of sources including satellite vegetation indices (such as the normalized difference vegetation index; NDVI) and atmospheric CO 2 measurements. Most of these changes have been attributed to strong warming trends in the northern high latitudes (⩾50° N). Here we analyze the interannual variation of summer net carbon uptake derived from atmospheric CO 2 measurements and satellite NDVI in relation to surface meteorology from regional observational records. We find that increases in spring precipitation and snow pack promote summer net carbon uptake of northern ecosystems independent of air temperature effects. However, satellite NDVI measurements still show an overall benefit of summer photosynthetic activity from regional warming and limited impact of spring precipitation. This discrepancy is attributed to a similar response of photosynthesis and respiration to warming and thus reduced sensitivity of net ecosystem carbon uptake to temperature. Further analysis of boreal tower eddy covariance CO 2 flux measurements indicates that summer net carbon uptake is positively correlated with early growing-season surface soil moisture, which is also strongly affected by spring precipitation and snow pack based on analysis of satellite soil moisture retrievals. This is attributed to strong regulation of spring hydrology on soil respiration in relatively wet boreal and arctic ecosystems. These results document the important role of spring hydrology in determining summer net carbon uptake and contrast with prevailing assumptions of dominant cold temperature limitations to high-latitude ecosystems. Our results indicate potentially stronger coupling of boreal/arctic water and carbon cycles with continued regional warming trends. (letters)
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Spring Hydrology Determines Summer Net Carbon Uptake in Northern Ecosystems
Yi, Yonghong; Kimball, John; Reichle, Rolf H.
2014-01-01
Increased photosynthetic activity and enhanced seasonal CO2 exchange of northern ecosystems have been observed from a variety of sources including satellite vegetation indices (such as the Normalized Difference Vegetation Index; NDVI) and atmospheric CO2 measurements. Most of these changes have been attributed to strong warming trends in the northern high latitudes (greater than or equal to 50N). Here we analyze the interannual variation of summer net carbon uptake derived from atmospheric CO2 measurements and satellite NDVI in relation to surface meteorology from regional observational records. We find that increases in spring precipitation and snow pack promote summer net carbon uptake of northern ecosystems independent of air temperature effects. However, satellite NDVI measurements still show an overall benefit of summer photosynthetic activity from regional warming and limited impact of spring precipitation. This discrepancy is attributed to a similar response of photosynthesis and respiration to warming and thus reduced sensitivity of net ecosystem carbon uptake to temperature. Further analysis of boreal tower eddy covariance CO2 flux measurements indicates that summer net carbon uptake is positively correlated with early growing-season surface soil moisture, which is also strongly affected by spring precipitation and snow pack based on analysis of satellite soil moisture retrievals. This is attributed to strong regulation of spring hydrology on soil respiration in relatively wet boreal and arctic ecosystems. These results document the important role of spring hydrology in determining summer net carbon uptake and contrast with prevailing assumptions of dominant cold temperature limitations to high-latitude ecosystems. Our results indicate potentially stronger coupling of boreal/arctic water and carbon cycles with continued regional warming trends.
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Caught in the Net: Perineuronal Nets and Addiction
Directory of Open Access Journals (Sweden)
Megan Slaker
2016-01-01
Full Text Available Exposure to drugs of abuse induces plasticity in the brain and creates persistent drug-related memories. These changes in plasticity and persistent drug memories are believed to produce aberrant motivation and reinforcement contributing to addiction. Most studies have explored the effect drugs of abuse have on pre- and postsynaptic cells and astrocytes; however, more recently, attention has shifted to explore the effect these drugs have on the extracellular matrix (ECM. Within the ECM are unique structures arranged in a net-like manner, surrounding a subset of neurons called perineuronal nets (PNNs. This review focuses on drug-induced changes in PNNs, the molecules that regulate PNNs, and the expression of PNNs within brain circuitry mediating motivation, reward, and reinforcement as it pertains to addiction.
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USE OF MIRROR PATTERN CUTTING OF NETTING MATERIALS FOR CONSTRUCTION OF LAKE BEACH SEINES
Directory of Open Access Journals (Sweden)
A. Nazarov
2014-12-01
Full Text Available Purpose. Justification and calculation of a new methodological approach to the construction of a standard beach seine (502 / 302 х 3.75 with the use of the properties of mirror netting ensuring the saving of the netting material, reduction of weight, price and drag resistance. Methodology. The carp age group selectivity of the constructed seine was assessed within fish fauna monitoring based on the catch analysis of monitoring gill nets with mesh sizes of 30-130 mm according to generally accepted methods [9, 10]. Calculation of netting materials and ropes was carried out according to generally accepted methods [12-14]. Seine resistance was calculated according to N. T. Senin formula for different netting materials and the angles of the movement of different seine parts in water [2]. The gear reliability and data processing were carried out according to standard methods [11, 14, 15]. Findings. A variant of the construction of the maximum lightweight beach lake seines made of mirror pattern netting taking into account the properties of the mirror pattern netting material, reduction of weight, price and drag resistance has been proposed. The provided recalculation of the properties of a serial seine made of rhombic mesh for the mirror netting seine taking into account netting properties allowed: 1 reducing the seine drag resistance value by 1,4 times; 2 reducing the weight of netting materials by 16.3% compared to the prototype; 3 increasing the seine selectivity when fishing older age groups of carp in non-drainable ponds. Originality. We presented the method of the calculation and construction of lake beach seines made of mirror netting, analyzed the technological stages of the construction of mirror netting, determined main qualitative and technological parameters, which had effect on the conditions of the construction and reliability of such fishing gears. A new method of the use of an insert of the combined netting material cutting ensuring
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Tangible interfaces in virtual environments, case study: Instituto de Engenharia Nuclear Virtual
Energy Technology Data Exchange (ETDEWEB)
Santo, Andre Cotelli do E.; Mol, Antonio Carlos A.; Pinto, Emanuele Oliveira; Melo, Joao Victor da C.; Paula, Vanessa Marcia de; Freitas, Victor Goncalves Gloria [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Machado, Daniel Mol [Coordenacao dos Programas de Pos-Graduacao em Engenharia (COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Instituto Alberto Luiz Coimbra
2015-07-01
Virtual Reality (VR) techniques allow the creation of realistic representations of an individual. These technologies are being applied in several fields such as training, simulations, virtual experiments and new applications are constantly being found. This work aims to present an interactive system in virtual environments without the use of peripherals typically found in computers such as mouse and keyboard. Through the movement of head and hands it is possible to control and navigate the virtual character (avatar) in a virtual environment, an improvement in the man-machine integration. The head movements are recognized using a virtual helmet with a tracking system. An infrared camera detects the position of infrared LEDs located in the operator's head and places the vision of the virtual character in accordance with the operator's vision. The avatar control is performed by a system that detects the movement of the hands, using infrared sensors, allowing the user to move it in the virtual environment. This interaction system was implemented in the virtual model of the Instituto de Engenharia Nuclear (IEN), which is located on the Ilha do Fundao - Rio de Janeiro - Brazil. This three-dimensional environment, in which avatars can move and interact according to the user movements, gives a feeling of realism to the operator. The results show an interface that allows a higher degree of immersion of the operator in the virtual environment, promoting a more engaging and dynamic way of working. (author)
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Tangible interfaces in virtual environments, case study: Instituto de Engenharia Nuclear Virtual
International Nuclear Information System (INIS)
Santo, Andre Cotelli do E.; Mol, Antonio Carlos A.; Pinto, Emanuele Oliveira; Melo, Joao Victor da C.; Paula, Vanessa Marcia de; Freitas, Victor Goncalves Gloria; Machado, Daniel Mol
2015-01-01
Virtual Reality (VR) techniques allow the creation of realistic representations of an individual. These technologies are being applied in several fields such as training, simulations, virtual experiments and new applications are constantly being found. This work aims to present an interactive system in virtual environments without the use of peripherals typically found in computers such as mouse and keyboard. Through the movement of head and hands it is possible to control and navigate the virtual character (avatar) in a virtual environment, an improvement in the man-machine integration. The head movements are recognized using a virtual helmet with a tracking system. An infrared camera detects the position of infrared LEDs located in the operator's head and places the vision of the virtual character in accordance with the operator's vision. The avatar control is performed by a system that detects the movement of the hands, using infrared sensors, allowing the user to move it in the virtual environment. This interaction system was implemented in the virtual model of the Instituto de Engenharia Nuclear (IEN), which is located on the Ilha do Fundao - Rio de Janeiro - Brazil. This three-dimensional environment, in which avatars can move and interact according to the user movements, gives a feeling of realism to the operator. The results show an interface that allows a higher degree of immersion of the operator in the virtual environment, promoting a more engaging and dynamic way of working. (author)
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International Nuclear Information System (INIS)
Kinoshita, S.; Ohtani, K.; Katayama, T.
2001-01-01
We started to release the K-NET strong-motion data from June 1996 and about one year passed. In this article, we report the development of K-NET and some applications using the K-NET information released on the Internet. (author)
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Silva, A. Christian; Prange, Richard E.
2007-03-01
We introduce the concept of virtual volatility. This simple but new measure shows how to quantify the uncertainty in the forecast of the drift component of a random walk. The virtual volatility also is a useful tool in understanding the stochastic process for a given portfolio. In particular, and as an example, we were able to identify mean reversion effect in our portfolio. Finally, we briefly discuss the potential practical effect of the virtual volatility on an investor asset allocation strategy.
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Incorporation of a Cuban radiological station to the global net of isotopes in precipitations
International Nuclear Information System (INIS)
Dominguez L, O.; Ramos V, E.O.; Prendes A, M.; Alonso A, D.; Caveda R, C.A.
2006-01-01
From March, 2002 the West station of the National Net of Environmental Radiological Surveillance located in the Center of Protection and Hygiene of the Radiations, belongs to the Global Net of Isotopes in Precipitations. The obtained isotopic information of the analysis of the samples of monthly monitored precipitations (oxygen-18, deuterium and tritium) its are stored in a database, which is available through Internet. For the acceptance in the Global Net, it was necessary the incorporation to the monitoring of the station the meteorological surface variables. Also it was developed a software for the calculation of the tension of the water steam starting from the values of humidity and temperature. The obtained results in 2002 and published recently, its are inside the range of values reported for these isotopes in the Caribbean area. (Author)
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Harri, A.-M.; Aleksashkin, S.; Arruego, I.; Schmidt, W.; Genzer, M.; Vazquez, L.; Haukka, H.; Palin, M.; Nikkanen, T.
2015-10-01
New kind of planetary exploration mission for Mars is under development in collaboration between the Finnish Meteorological Institute (FMI), Lavochkin Association (LA), Space Research Institute (IKI) and Institutio Nacional de Tecnica Aerospacial (INTA). The Mars MetNet mission is based on a new semihard landing vehicle called MetNet Lander (MNL). The scientific payload of the Mars MetNet Precursor [1] mission is divided into three categories: Atmospheric instruments, Optical devices and Composition and structure devices. Each of the payload instruments will provide significant insights in to the Martian atmospheric behavior. The key technologies of the MetNet Lander have been qualified and the electrical qualification model (EQM) of the payload bay has been built and successfully tested.
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Virtual laboratories : comparability of real and virtual environments for environmental psychology
Kort, de Y.A.W.; IJsselsteijn, W.A.; Kooijman, J.M.A.; Schuurmans, Y.
2003-01-01
Virtual environments have the potential to become important new research tools in environment behavior research. They could even become the future (virtual) laboratories, if reactions of people to virtual environments are similar to those in real environments. The present study is an exploration of
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Energy Technology Data Exchange (ETDEWEB)
Heilbron Filho, Paulo Fernando Lavalle
1984-04-15
This work is a continuation of many others studies that have been made in the field of two-phase flow, concerning the influence of the void fraction in a parameter known as 'induced mass' that appears in the constitutive equation of the inter-phase force called 'virtual mass force'. The determination of the influence of the void fraction in the induced mass is done using experiment involving a bubble flow in a vertical tube filled with water. Using the two-phase flow model together with some hypothesis concerning the bubble flow experience and the constitutive equation for the virtual mass force, we achieve through the analysis of the filming of the experiment our purpose in determining the influence of the void fraction on the induced mass. (author)