WorldWideScience
1

The potential of periphyton-based aquaculture production systems  

OpenAIRE

Key words : Periphyton; Biofilm; Artificial substrates; Pond productivity; Tropical aquaculture; Monoculture; Polyculture; Fertilization; Proximate composition; Stocking ratio; Stable isotope ratio; Nutrient efficiency; Production economics; Indian major carps; Catla catla ; Labeo rohita ; Labeo gonius ; Labeo calbasu . The overall objective of this study was to determine the technical and economical performance of periphyton-based aquaculture systems in Bangladesh. It thus addressed one of ...

Ul Azim, M. E.

2001-01-01

2

Does aquaculture add resilience to the global food system?  

Science.gov (United States)

Aquaculture is the fastest growing food sector and continues to expand alongside terrestrial crop and livestock production. Using portfolio theory as a conceptual framework, we explore how current interconnections between the aquaculture, crop, livestock, and fisheries sectors act as an impediment to, or an opportunity for, enhanced resilience in the global food system given increased resource scarcity and climate change. Aquaculture can potentially enhance resilience through improved resource use efficiencies and increased diversification of farmed species, locales of production, and feeding strategies. However, aquaculture's reliance on terrestrial crops and wild fish for feeds, its dependence on freshwater and land for culture sites, and its broad array of environmental impacts diminishes its ability to add resilience. Feeds for livestock and farmed fish that are fed rely largely on the same crops, although the fraction destined for aquaculture is presently small (?4%). As demand for high-value fed aquaculture products grows, competition for these crops will also rise, as will the demand for wild fish as feed inputs. Many of these crops and forage fish are also consumed directly by humans and provide essential nutrition for low-income households. Their rising use in aquafeeds has the potential to increase price levels and volatility, worsening food insecurity among the most vulnerable populations. Although the diversification of global food production systems that includes aquaculture offers promise for enhanced resilience, such promise will not be realized if government policies fail to provide adequate incentives for resource efficiency, equity, and environmental protection. PMID:25136111

Troell, Max; Naylor, Rosamond L; Metian, Marc; Beveridge, Malcolm; Tyedmers, Peter H; Folke, Carl; Arrow, Kenneth J; Barrett, Scott; Crépin, Anne-Sophie; Ehrlich, Paul R; Gren, Asa; Kautsky, Nils; Levin, Simon A; Nyborg, Karine; Österblom, Henrik; Polasky, Stephen; Scheffer, Marten; Walker, Brian H; Xepapadeas, Tasos; de Zeeuw, Aart

2014-09-16

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Recirculating Systems for Pollution Prevention in Aquaculture Facilities  

Directory of Open Access Journals (Sweden)

Full Text Available As all other forms of livestock production, fish farming has numerous environmental impacts. Water pollution is one of the most significant outcomes, since aquaculture effluents contain non-ingested food and fish dregs that affect the receiving water bodies when discharged without any treatment. Conventional pollutants (suspended solids, dissolved organic matter and nutrients, as well as pesticides, heavy metals and emerging pollutants (as antibiotics and hormones, are commonly found in these effluents. Recirculating aquaculture systems (RAS, systems that integrate the treatment and the reuse of water in the process are an invaluable alternative for preventing water pollution by diminishing both the volume and the eutrophication potential of the effluents. Based on our review of the extant literature in the field, we conclude that activated carbon-based biofilters are a favorable technology to achieve a level of water quality that is compatible with environmentally-sound aquaculture practices.

Maribel Quezada-Cruz

2013-07-01

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An Inexpensive Recirculating Aquaculture System with Multiple Use Capabilities.  

Science.gov (United States)

Describes the construction of an inexpensive recirculating aquaculture system that can hold up to 46 pounds of fish, invertebrates, and mussels for classroom use. The system is versatile, requires little maintenance, and can be used for both teaching and research purposes. (WRM)

Scurlock, Gerald Don, Jr.; Cook, S. Bradford; Scurlock, Carrie Ann

1999-01-01

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Aquaculture Network Information Center  

Science.gov (United States)

Given the declining schools of fish in many of the world's oceans, interest in aquaculture has grown exponentially in the past few years. The Aquaculture Network Information Center (ANIC) serves as an electronic gateway to thousands of online aquaculture-related resources, and is hosted by Purdue University and the University of Illinois through the Illinois - Indiana Sea Grant College Program. ANIC was started in 1994, and currently contains links to hundreds of aquaculture publications from around the globe, visual media (such as Power Point presentations), calendars of germane conferences and events, and specialty sections for species and production systems. From the ANIC home page, visitors may join discussion groups about aquaculture (organized by species), learn about different aquaculture cultivation systems, and peruse recent and archive publications from the relevant federal, state, and international agencies. For aquaculture neophytes, a FAQ section will answer ever quandary possible about the world of pond management, the perplexity of pond construction, and the inevitable debates surrounding which form of aquaculture production is most appropriate for different regions of the world.

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ECONOMIC ASSESSMENT OF WASTE WATER AQUACULTURE TREATMENT SYSTEMS  

Science.gov (United States)

This study attempted to ascertain the economic viability of aquaculture as an alternative to conventional waste water treatment systems for small municipalities in the Southwestern region of the United States. A multiple water quality objective level cost-effectiveness model was ...

7

ALTERNATIVE PRACTICE FROM COASTAL POND TO RECIRCULATION AQUACULTURE SYSTEM  

Directory of Open Access Journals (Sweden)

Full Text Available Coastal pond aquaculture used solar energy to produce oxygen via phytoplankton with their cultivation can be extensive such as the culture of low value cultured animals. Pond encompasses a larger culture area for juvenile or grow-out culture which is depending on their carrying capacity of the pond. There is no feeding and the amount of food available depends on pond management which can be increased by manuring. As well as in hatcheries that require a very well environmental control, Recirculation aquaculture systems (RAS tend to occupy a small area to culture high value species at high densities. The key parameter affecting RAS is the biological filtration system that removes metabolic and other waste products. This contains bacteria which break down the ammonia and nitrite in the water. Moreover, the food from RAS is supplied externally from cultured or formulated feed. Recirculation systems offer the advantage over pond aquaculture of being able to control the environment and water quality parameters to optimise fish health. For production of commodity food fish that are low in price, pond aquaculture is better than recirculation system due to their lower overheads and production cost as the environment acts as a natural water reconditioning system compared to money spent on water recirculation technology. In developing countries, pond will still remain dominant due to the ease of culture and the low initial investments. While, in developed countries, the growing concern about environmentally friendly discharges, the high labour costs and the need for controlling niche markets will result in the adoption of recirculation technology and the production of high value species at high densities. In comparison to pond culture, RAS offered more control and independent from the environment influence.

Ludi Parwadani Aji

2012-02-01

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Solar energy system design for a lobster aquaculture facility  

Energy Technology Data Exchange (ETDEWEB)

In aquaculture, as in most manufacturing processes, the operating cost is greatly dependent upon the cost of energy. The objectives were to: (a) analyze the power requirements for a lobster aquaculture plant, and (b) to evaluate the use of solar energy as a cost reduction measure in plant operation. A flat plate collector system capable of supplying heat alone was compared with a total energy system in which both electrical power and heat were supplied. The flat plate collector was not cost effective because when heat was needed in December, the least amount of heat was available from solar radiation. Therefore, the collector area and cost were prohibitive. However, the total energy system was cost effective when the capital investment was amortized over ten or more years. The optimum solar power plant was designed to provide 100% of the average yearly power demands, or 60% of the December power requirement. This plant would consist of 60,000 square feet of mirror surface (3.5 acres of land for 40% packing density) which would concentrate 1500 to 2000 suns on a receiver mounted on an 85 foot tower. In the tower would be the three storage stoves which would contain the heat required to operate a 343 KWe Brayton gas turbine engine and alternator for 27 hours. Equipment to generate 3 million kw-hr annually will cost an estimated $1.3 million.

1977-09-30

9

Exergetic performance analysis of a recirculating aquaculture system  

Energy Technology Data Exchange (ETDEWEB)

This paper examines exergetic aspects of a Recirculation Aquaculture System (RAS) for Black Sea trout (Salmo trutta labrax) fingerling rearing at the Trabzon Central Fisheries Research Institute, Turkey. In its thermodynamic analysis, each component of the RAS is treated as a steady-state steady flow system and its exergetic efficiencies are studied. In addition, the following parameters are measured and recorded in experiments: the mass flow rates, inlet and outlet temperatures and of the system components, surrounding temperatures, and electrical work utilized by the components in the RAS. Based on these experimental data, inlet and outlet exergy values, exergy losses, and exergetic efficiencies of each component in the system are determined to assess their performance. Moreover, the overall system exergy efficiency is determined. The results show that exergy efficiencies of the system components are highly affected by varying input exergy flows as a function of the surrounding temperature and chiller's operating period. (author)

Kucuk, Haydar [Mechanical Engineering Department, Guemueshane University, 29000 Guemueshane (Turkey); Midilli, Adnan [Energy Division, Mechanical Engineering Department. Nigde University, 51000 Nigde (Turkey); Oezdemir, Atilla; Cakmak, Eyuep [Central Fisheries Research Institute, Ministry of Agricultural and Rural Affairs, Trabzon (Turkey); Dincer, Ibrahim [Faculty of Engineering and Applied Science, University of Ontario Institute of Technology, 2000 Simcoe Street North, Oshawa, Ont. (Canada)

2010-05-15

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Exergetic performance analysis of a recirculating aquaculture system  

International Nuclear Information System (INIS)

This paper examines exergetic aspects of a Recirculation Aquaculture System (RAS) for Black Sea trout (Salmo trutta labrax) fingerling rearing at the Trabzon Central Fisheries Research Institute, Turkey. In its thermodynamic analysis, each component of the RAS is treated as a steady-state steady flow system and its exergetic efficiencies are studied. In addition, the following parameters are measured and recorded in experiments: the mass flow rates, inlet and outlet temperatures and of the system components, surrounding temperatures, and electrical work utilized by the components in the RAS. Based on these experimental data, inlet and outlet exergy values, exergy losses, and exergetic efficiencies of each component in the system are determined to assess their performance. Moreover, the overall system exergy efficiency is determined. The results show that exergy efficiencies of the system components are highly affected by varying input exergy flows as a function of the surrounding temperature and chiller's operating period.

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The Use of Vision in a Sustainable Aquaculture Feeding System  

Directory of Open Access Journals (Sweden)

Full Text Available Dairy feeding causes significant water pollution. By controlling the proper amount of feed, reducing the waste to minimum will effectively reduce the problem of water contamination. In this project, a Sustainable Aquaculture Feed System (SAFS has been designed and developed. It can automatically feed the fishes by estimating fishes’ appetite through machine vision. The discussion includes design and optimization of the vision system using Labview as well as the integration of various components in the SAFS. With the developed algorithm, the system is able to detect the presence of fishes and count the number of fishes. The outcome is able to estimate and infer the fish appetite. Therefore, the feeding time can be planned ahead. In addition, the system includes a Graphical User Interface (GUI for monitoring, display the feeding status and sensors reading such as pH, turbidity and temperature.

Jer-Vui Lee

2013-10-01

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Aquaculture Industry Potential and Issues: A Case from Cage Culture System Entrepreneurs: Suggestions for Intensification of Aquaculture Industry  

Directory of Open Access Journals (Sweden)

Full Text Available Problem statement: Cage culture has become a popular aquaculture system nowadays. In the recent statistics provided by DOF, the cage culture system has generated almost USD 400 m (RM 1.39 b of income per year. In order to further intensify this economic activity the Ministry of Agriculture and Agro-based Industry (MOA through the DOF has zoned the aquaculture industry via Aquaculture Industry Zone (ZIA Programs throughout Malaysia. Cage culture system seems to have the ability to be a catalyst in enhancing the economy level of local people but it is well known that certain problems must be overcome first before the potential can be clearly seen. Thus the main focus of this study is to clarify all the potentials and problems faced by the cage culture system entrepreneurs in running their aquaculture activity. Approach: The research approach for this study was a qualitative case study that provided an in-depth description of potentials and issues in aquaculture industry in the district of Kuala Pahang, Malaysia. Data was gained using a Focus Group Discussion (FGD among the cage culture system entrepreneurs guided by an interview guide. A total of 10 cage culture entrepreneurs were selected as the FGD members. The questions served as a guide, but allowed respondents freedom and flexibility in their answers. The findings were in descriptive analysis. Results: The cage culture system was found to provide better income that lead to a higher quality of life for the entrepreneurs, positive intangible values existed among the entrepreneurs; experiences have taught them to become self independent. There were problems identified such as no independence in selecting the fingerlings, environmental problems seem to burden them, unstable pellet price, no official agreement between them and the government emphasizing the portion of the river is given to them for running their business and lot of bureaucracies that the entrepreneurs need to face. Conclusion/Recommendations: Based on the results gained, it can be concluded that even though cage culture industry proved to enhance the level of income and quality of life, a number of problems must be overcome first to further enhance their level of income and quality of life. Therefore, it is a need that the related agencies to provide more financial supports help to solve the environmental problems and further develop their administration aspects to reduce issues such as bureaucracy and official agreement.

A. N.A. Faiz

2010-01-01

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Bacterial resistance to oxytetracycline in different life stages of Indian freshwater carp aquaculture system  

OpenAIRE

In India antibiotics are frequently used for preventing and controlling bacterial pathogens incarp aquaculture system, yet no studies have been performed to evaluate the ecological impact of itsintensive and prolonged use. In this work the frequency of oxytetracycline-resistant bacteria from water,palletized feed and different life stages of fish from Indian freshwater carp aquaculture system as well asthe level of resistance of selected strains was investigated. Viable as well as antibiotic-...

Singh A.K.; Rathore G; Singh V.; Mani I.; Singh R.K; Mishra S K; Mishra B.N.; Verma O.P.

2009-01-01

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Microscreen effects on water quality in replicated recirculating aquaculture systems  

DEFF Research Database (Denmark)

This study investigated the effects of three microscreen mesh sizes (100, 60 and 20 ?m) on water quality and rainbow trout (Oncorhynchus mykiss) performance compared to a control group without microscreens, in triplicated recirculating aquaculture systems (RAS). Operational conditions were kept constant during a 6-week period where the microscreens were manually rinsed three times a day. The effects of microscreen cleaning frequency and nitrification performance were subsequently assessed. Compared to the control group, microscreens removed particles, reduced particulate organic matter, and increased ?-values. Particulate parameters reached steady-state in all treatment groups having microscreens at the end of the trial. The time to reach equilibrium seemingly increased with increasing mesh size but the three treatment groups (100, 60 and 20 ?m) did not significantly differ at the end of the trial. Increased backwashing frequency over a 24-h period had no further significant effects on the parameters measured. The results demonstrated the role and importance of a microscreen, and showed that mesh size, within the range tested, is less important at long operations under constant conditions. Fish performed similarly in all treatments. Preliminary screening of trout gills did not reveal any pathological changes related to microscreen filtration and the resulting water quality. Biofilter performance was also unaffected, with 0?-order nitrification rates (k0a) being equivalent for all twelve systems (0.148 ± 0.022 g N m?2 d?1). Mechanisms for RAS equilibrium establishment, within and between systems with different mesh sizes, are discussed

Fernandes, Paulo; Pedersen, Lars-Flemming

2014-01-01

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Participatory Monitoring and Feedback System: An Important Entry Towards Sustainable Aquaculture in Bolinao, Northern Philippines  

Directory of Open Access Journals (Sweden)

Full Text Available The aquaculture industry in Caquiputan Channel contributed P2.3M to municipal revenues in 1998. However, the uncontrolled construction of fish pens and fish cages have contributed to the deterioration of the water quality in the Caquiputan Channel. Despite monitoring of parameters (e.g. DO, salinity, and temperature, low production was implicated because of limited dissolved oxygen supply.A participatory monitoring of fish pens and fish cages was facilitated to pave the way for sustainable aquaculture. A system for monitoring and disseminating information on water quality, production and zonation of pens and cages, has been pursued to assess the situation and identify mechanisms to regulate aquaculture activities. The feedback system adopted has raised and facilitated environmental awareness, issue identification, and implementation, of solutions to some major issues. Furthermore, the results have resulted in policy reforms, as embodied in the provisions on aquaculture in the Municipal Fisheries Ordinance.

Lailany Verceles

2000-12-01

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Nutrient fate in aquacultural systems for waste treatment  

Energy Technology Data Exchange (ETDEWEB)

Twelve small, recirculating aquacultural systems were operated for livestock waste treatment to determine nutrient fate. Each system consisted of a 730-L fish tank coupled in a recirculating loop with three sand beds (serving as biofilters) in parallel. Fish (Tilapia species) were grown in the tanks while cattails, reed canary grass, and tomatoes were grown in separate sand beds. Swine waste was added to the fish tanks every other day at average rates of 50, 72, 95, and 118 kg-COD/ha/day of fish tank surface (three replications of each loading rate). Water from the fish tanks was filtered through the sand beds three times per day with 20% of the tank volume passing through the sand each day. The systems were operated in a greenhouse for eight months (21 July to 8 March). Aboveground plant matter was harvested at eight-week intervals. The fish were removed after four months and the tanks were restocked with fingerlings. Initial and final nitrogen (N), phosphorus (P), and potassium (K) contents of the system components, as well as that of the harvested plants and fish, were determined. Nutrient balance calculations revealed that 30 to 68% of added N was lost from the systems, probably via denitrification. Nutrient removal by plants was 6 to 18% for N, 8 to 21% for P, and 25 to 71% for K, with tomatoes (foliage and fruit) accounting for the majority of the removal. Plant growth was limited by growing conditions (particularly day length), not be nutrient availability. Fish growth was limited by temperature; thus nutrient extraction by the fish was minimal. Under the conditions of this experiment, the system required supplemental aeration.

Dontje, J.H.; Clanton, C.J.

1999-08-01

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Multidrug-Resistance and Toxic Metal Tolerance of Medically Important Bacteria Isolated from an Aquaculture System  

OpenAIRE

The use of antimicrobials and toxic metals should be considered carefully in aquaculture and surrounding environments. We aimed to evaluate medically relevant bacteria in an aquaculture system and their susceptibility to antimicrobials and toxic metals. Selective cultures for enterobacteria (ENT), non-fermenting Gram-negative rods (NFR) and Gram-positive cocci (GPC) were obtained from water samples collected in two different year seasons. The isolated bacteria were biochemically identified an...

Resende, Juliana Alves; Silva, Va?nia L.; Fontes, Cla?udia Oliveira; Souza-filho, Job Alves; Oliveira, Tamara Lopes Rocha; Coelho, Ci?ntia Marques; Ce?sar, Dione?ia Evangelista; Diniz, Cla?udio Galuppo

2012-01-01

18

Geothermal aquaculture project: Real Property Systems Inc. , Harney Basin, Oregon  

Energy Technology Data Exchange (ETDEWEB)

Real Property Systems Inc., (RPS) owns two parcels in the vicinity of Harney Lake, Oregon. One parcel is 120 acres in size, the other is 200 acres. A study concludes that the 200 acre parcel has the greater potential for geothermal development. RPS is interested in an aquaculture operation that produces fresh water prawns, (Macrobrachium rosenbergii) for the market. To supply the heat necessary to maintain the ideal temperature of 82/sup 0/F desired for these prawns, a geothermal resource having a 150/sup 0/F temperature or higher, is needed. The best estimate is that 150/sup 0/F water can be found from a minimum 1090 feet depth to 2625 feet, with no absolute assurances that sufficient quantities of geothermal waters exist without drilling for the same. This study undertakes the preliminary determination of project economics so that a decision can be made whether or not to proceed with exploratory drilling. The study is based on 10 acres of ponds, with a peak requirement of 2500 gpm of 150/sup 0/F geothermal water.

1981-08-14

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Aquaculture; Acquacoltura  

Energy Technology Data Exchange (ETDEWEB)

This paper attempts an overview of the progress made in the field of aquaculture. Aquaculture is a system of techniques strongly influenced by natural environmental conditions. Aquaculture as a biological technique oriented towards the production of useful aquatic organisms, is reaching a stage of consolidation which will place it on an equal footing which agriculture and animal husbandry. Aquaculture provides important economic and nutritional benefits to many regions of developing world. In 1994, over 90 percent of total aquaculture production was in Asia, with China, India, Japan, Indonesia, Thailand, Philippines and Republic of Korea as the seven leader producers. [Italiano] L`acquacoltura, vale a dire l`arte di riprodurre artificialmente pesci, alghe, molluschi e crostacei ed altri organismi acquatici utili all`uomo, si presenta oggi come un`attivita` di assoluto rilievo nell`insieme dei vari comparti di produzione alimentare. L`aumento della produzione e` costante anche se cinque paesi asiatici (Cina, India, Giappone, Filippine e Corea del Sud) contribuiscono per l`80% al volume della produzione mondiale. Nel presente lavoro vengono descritti lo stato dell`acquacoltura e della maricoltura nel mondo e le filiere di allevamento delle principali specie.

De Murtas, I.D. [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dipt. Ambiente

1998-12-01

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Use of a micro programmable logic controller for oxygen monitoring and control in multiple tanks of a recirculating aquaculture system  

Science.gov (United States)

In intensive recirculating aquaculture systems the use of supplemental oxygen, specifically pure liquid oxygen, increases the mass of fish that can be supported and eliminates oxygen as a major limiting factor to a system’s carrying capacity. The use of pure oxygen in a recirculating aquaculture sys...

21

An agro-ecological evaluation of aquaculture integration into farming systems of the Mekong Delta  

OpenAIRE

This study compared ecological sustainability of Integrated Agriculture-Aquaculture (IAA) systems with different forms and intensity of aquaculture integration in the Mekong Delta of Vietnam: orchard-based and low-input fish (O-LF); rice-based and medium-input fish (R-MF); and rice-based and high-input fish (R-HF) farming systems. We monitored eleven IAA-farms from September 2002 to September 2004. ECOPATH models, based on nitrogen flows, produced 19 agro-ecological system attributes that wer...

Phong, L. T.; Dam, A. A.; Udo, H. M. J.; Mensvoort, M. E. F.; Tri, L. Q.; Steenstra, F. A.; Zijpp, A. J.

2010-01-01

22

Measuring System for Growth Control of the Spirulina Aquaculture  

Science.gov (United States)

It describes the workings of a data-logging instrument that measures growth levels of the Spirulina aquaculture. The Spirulina is a very delicate algae and its culture may be suddenly lost due to overgrowth. This kind of instrument is not at present available in the market. The transduction is a submergible laser device whose measuring margin of error is near to 0.28%. The advantage of this new instrument is the improvement in the measurement and the low cost. The future application of this work is related to the industrial production of food and fuel from micro algae culture, for the growing world population.

Ponce S., Claudio; Ponce L., Ernesto; Bernardo S., Barraza

2008-11-01

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Context-Aware Services in Aquaculture : FiFaMoS - Fish Farm Monitoring System  

OpenAIRE

This thesis focuses on context-aware services that make decisions based on the situation (i.e. context) of the involved entities. Context may in general be based on user input, sensed or derived (e.g. combination of multiple context entities). The type of such services is vast, but in this thesis the system is aimed towards the aquaculture industry. During the last years, aquaculture quality has become more and more important in the fish farming industry. But this importance has not been re...

Grødal, Jon Arne; Paaske, Frank Gjervik

2006-01-01

24

Biodiesel Production by the Green Microalga Scenedesmus obliquus in a Recirculatory Aquaculture System  

OpenAIRE

Biodiesel production was examined with Scenedesmus obliquus in a recirculatory aquaculture system with fish pond discharge and poultry litter to couple with waste treatment. Lipid productivity of 14,400 liter ha?1 year?1 was projected with 11 cultivation cycles per year. The fuel properties of the biodiesel produced adhered to Indian and international standards.

Mandal, Shovon; Mallick, Nirupama

2012-01-01

25

Low-dose hydrogen peroxide application in closed recirculating aquaculture systems  

Science.gov (United States)

The aim of the present work was to simulate water treatment practice with hydrogen peroxide (HP) in recirculating aquaculture systems (RAS). Six identical 1700 L pilot scale RAS were divided into two experimental groups based on daily feed allocation and were operated under constant conditions durin...

26

Geosmin causes off-flavour in arctic charr in recirculating aquaculture systems  

Science.gov (United States)

The “earthy” and “muddy” off-flavors in pond-reared fish are due to the presence of geosmin or 2-methylisoborneol (MIB) in the flesh of the fish. Similar off-flavors have been reported in fish raised in recirculating aquaculture systems (RAS); however, little information is available regarding the ...

27

Purification Performance and Production of a Re-circulating Pond Aquaculture System Based on Paddy Field  

Directory of Open Access Journals (Sweden)

Full Text Available Developing improved aquaculture systems with a more efficient use of water and less environmental impact is becoming a crying need. A re-circulating aquaculture system consisting of paddy field and fish pond is a new culture mode due to aquaculture combing with agriculture. The present study focused on the purification capacity of the paddy field on nitrogen, phosphorus and organic matter, the fluctuation trend of water quality conditions during the whole rearing process and the culture efficacy of the main culture species of grass carp (Ctenopharyngodon idella. The results were as follows: under a flow rate of 1.4-5.5 m3/h for the recirculation treatment, the average removal rate of ammonia nitrogen, nitrate nitrogen, total nitrogen, total phosphorus and biochemical oxygen demand for the aquaculture effluent amounted to 40.5, 43.5, 31.9, 23.9, 20.7 and 52.4%, respectively, But the dissolved oxygen content in the rice fields increased obviously. During the whole process of fish rearing, the main physicochemical parameters of water quality for the experimental ponds were all maintained at a suitable level for the growth of the grass carp. In addition, there were significant differences (p<0.05 in DO, TSS, NH4+ -N, NO--N, BOD5 and Chl-&alpha between the experimental and control ponds. As far as the yield per unit and survival rate was concerned, the level of the experimental ponds was obviously higher than that of the control, while the feed conversion ratio displayed the opposite trend. Overall, the new aquaculture system realized the double aims of water reuse and the reduction of waste water discharge.

Gu Li

2012-10-01

28

Recent advances within intensive Recirculated Aquaculture System cultivation of the calanoid copepod Acartia tonsa (Dana)  

DEFF Research Database (Denmark)

Danish aquaculture has within recent years focused upon rearing of new marine fish species. A major challenge for rearing of marine fish species is relevant diets for their fish larvae. Copepods and their larvae stage “nauplii” are well documented as the ideal live feed for a variety of marine aquaculture species. Copepodites and nauplii are superior as live feed compared to rotifers and Artemia both in terms of nutritional value, behaviour and prey size. In 1980s the copepod Acartia tonsa (Dana) was isolated in the Danish strait of Øresund and has been studied and kept in cultures ever since. An interesting trait with the species is that the eggs can be provoked into a resting stage, where the egg can be stored for one year, similar to Artemia cysts. This is the most promising storage technique for distribution of copepod eggs to aquaculture facilities worldwide. The eggs can be hatched and the nauplii can be feed to marine fish larvae. A restriction is that copepod cultures for producing eggs are after 30years of research still not stable and in large enough scale for bulk production of eggs. Recently a unique copepod Recirculated Aquaculture System (RAS) at Roskilde University (Denmark) was constructed as a part of the IMPAQ project “IMProvement of AQuaculture high quality fish fry production”. We present recent advance within RAS culture for copepods, and lesson learned from rearing the specie. Further we present physical and biological culture restrictions in terms of water quality (NH3), chemical and physical copepod densities, and its effects on copepod egg production (fecundity). We found that NH3 affect nauplii cultures negatively at levels above 30 ?g NH3 L-1, and adult cultures at levels above 477 ?g NH3 L-1. In terms of chemical and physical densities egg production was limited at densities above 2000 adults L-1.

Jepsen, Per Meyer; HØjgaard, Jacob Kring

29

Degradation and effect of hydrogen peroxide in small-scale recirculation aquaculture system biofilters  

OpenAIRE

From an environmental point of view, hydrogen peroxide (HP) has beneficial attributes compared with other disinfectants in terms of its ready degradation and neutral by-products. The rapid degradation of HP can, however, cause difficulties with regard to safe and efficient water treatment when applied in different systems. In this study, we investigated the degradation kinetics of HP in biofilters from water recirculating aquaculture systems (RAS). The potential effect of HP on the nitrificat...

Møller, Martin Sune; Arvin, Erik; Pedersen, Lars-flemming

2009-01-01

30

A ZigBee Wireless Sensor Network for Monitoring an Aquaculture Recirculating System  

OpenAIRE

A ZigBee wireless sensor network was developed for monitoring an experimental aquaculture recirculating system.Temperature, dissolved oxygen, water and air pressure as well as electric current sensors were included in the setup.The high fish densities required in these systems to become economically viable present a case where sensornetworks can be applied to preserve a healthy livestock and to reduce the risk of failures that end up in the loss ofproduction. Modules for reading and transmitt...

Espinosa-faller, Francisco J.; Rendo?n-rodri?guez, Guillermo E.

2012-01-01

31

A ZigBee Wireless Sensor Network for Monitoring an Aquaculture Recirculating System  

Directory of Open Access Journals (Sweden)

Full Text Available A ZigBee wireless sensor network was developed for monitoring an experimental aquaculture recirculating system.Temperature, dissolved oxygen, water and air pressure as well as electric current sensors were included in the setup.The high fish densities required in these systems to become economically viable present a case where sensornetworks can be applied to preserve a healthy livestock and to reduce the risk of failures that end up in the loss ofproduction. Modules for reading and transmitting sensor values through a ZigBee wireless network were developedand tested. The modules were installed in an aquaculture recirculating system to transmit sensor values to thenetwork coordinator. A monitoring program was created in order to display and store sensor values and to comparethem with reference limits. An alert is emitted in case reference limits have been reached. E-mail and an SMSmessage alert can also be sent to the cellular phone of the system administrator, so immediate action can be taken. Aweb interface allows Internet access to the sensor values. The present work demonstrates the applicability of ZigBeewireless sensor network technology to aquaculture recirculating systems.

Francisco J. Espinosa-Faller

2012-06-01

32

Wastewater Utilization for Poly-?-Hydroxybutyrate Production by the Cyanobacterium Aulosira fertilissima in a Recirculatory Aquaculture System?  

OpenAIRE

Intensive aquaculture releases large quantities of nutrients into aquatic bodies, which can lead to eutrophication. The objective of this study was the development of a biological recirculatory wastewater treatment system with a diazotrophic cyanobacterium, Aulosira fertilissima, and simultaneous production of valuable product in the form of poly-?-hydroxybutyrate (PHB). To investigate this possible synergy, batch scale tests were conducted under a recirculatory aquaculture system in fiber-r...

Samantaray, Shilalipi; Nayak, Jitendra Kumar; Mallick, Nirupama

2011-01-01

33

An economic analysis of the use of recirculating aquaculture systems in the production of Tilapia  

OpenAIRE

An economic analysis of tilapia production was conducted using a recirculating aquaculture system facility, situated at the Norwegian University of Life Science (UMB). The goals were; (1) to evaluate and estimate the operational cost involved and from this, estimate the breakeven cost, (2) identify and describe the constraints unique to the RAS, (3) to perform financial feasibility of a (hypothetical) scale-up production, and (4) to conduct sensitivity analysis on some variables to highlight ...

Appiah-kubi, Frank

2012-01-01

34

Fixed-biofilm reactors applied to waste water treatment and aquacultural water recirculating systems.  

OpenAIRE

Fixed-biofilm waste water treatment may be regarded as one of the oldest engineered biological waste water treatment methods. With the recent introduction of modern packing materials, this type of reactor has received a renewed impuls for implementation in a wide field of water treatment.In this thesis the possibilities are presented for fixed-film post-treatment of anaerobically digested domestic sewage and water reconditioning in aquacultural water recirculation systems. Emphasis is put on ...

Bovendeur, J.

1989-01-01

35

Multidrug-resistance and toxic metal tolerance of medically important bacteria isolated from an aquaculture system.  

Science.gov (United States)

The use of antimicrobials and toxic metals should be considered carefully in aquaculture and surrounding environments. We aimed to evaluate medically relevant bacteria in an aquaculture system and their susceptibility to antimicrobials and toxic metals. Selective cultures for enterobacteria (ENT), non-fermenting Gram-negative rods (NFR) and Gram-positive cocci (GPC) were obtained from water samples collected in two different year seasons. The isolated bacteria were biochemically identified and antimicrobial and toxic metal susceptibility patterns were determined. Overall, 407 representative strains were recovered. In general, bacteria isolated from fish ponds showed higher multiple antibiotic resistance indices when compared to those isolated from a water-fed canal. Resistance to penicillin and azithromycin was observed more frequently in the GPC group, whereas resistance to ampicillin and ampicillin/sulbactam or gentamicin was observed more frequently in the ENT and NFR groups, respectively. All the isolated bacteria were tolerant to nickel, zinc, chromium and copper at high levels (?1,024 ?g mL(-1)), whereas tolerance to cadmium and mercury varied among the isolated bacteria (2-1,024 ?g mL(-1)). Multidrug-resistant bacteria were more frequent and diverse in fish ponds than in the water-fed canal. A positive correlation was observed between antimicrobial resistance and metal tolerance. The data point out the need for water treatment associated with the aquaculture system. PMID:22972388

Resende, Juliana Alves; Silva, Vânia L; Fontes, Cláudia Oliveira; Souza-Filho, Job Alves; Rocha de Oliveira, Tamara Lopes; Coelho, Cíntia Marques; César, Dionéia Evangelista; Diniz, Cláudio Galuppo

2012-01-01

36

Fate of water borne therapeutic agents and associated effects on nitrifying biofilters in recirculating aquaculture systems  

DEFF Research Database (Denmark)

Recent discharge restrictions on antibiotics and chemotherapeutant residuals used in aquaculture have several implications to the aquaculture industry. Better management practices have to be adopted, and documentation and further knowledge of the chemical fate is required for proper administration and to support the ongoing development of a sustainable aquaculture industry. A focal point of this thesis concerns formaldehyde (FA), a commonly used chemical additive with versatile aquaculture applications. FA is safe for use with fish and has a high treatment efficiency against fungal and parasite infections; however, current treatment practices have proven difficult to comply with existing discharge regulations. Hydrogen peroxide (HP) and peracetic acid (PAA) are potential candidates to replace FA, as they have similar antimicrobial effects and are more easily degradable than FA, but empirical aquaculture experience is limited. The two main objectives of this Ph.D. project were to 1) investigate the fate of FA in nitrifying aquaculture biofilters, focusing on factors influencing degradation rates, and 2) investigate the fate of HP and PAA in nitrifying aquaculture biofilters and evaluate the effects of these agents on biofilter nitrification performance. All experiments were conducted through addition of chemical additives to closed pilot scale recirculating aquaculture systems (RAS) with fixed media submerged biofilters under controlled operating conditions with rainbow trout (Oncorhynchus mykiss) in a factorial design with true replicates. Biofilter nitrification performances were evaluated by changes in chemical processes, and nitrifying populations were identified by fluorescence in situ hybridisation (FISH) analysis. FA was degraded at a constant rate immediately after addition, and found to positively correlate to temperature, available biofilter surface-area, and the frequency of FA-exposure. Prolonged biofilter exposure to FA did not negatively affect nitrification, and could therefore be a method to optimize FA treatment in RAS and reduce FA discharge. HP degradation was rapid and could be described as a concentration-dependent exponential decay. HP was found to be enzymatically eliminated by microorganisms, with degradation rates correlated to organic matter content and microbial abundance. Nitrification performance was not affected by HP when applied in dosages less than 30 mg/L, whereas prolonged multiple HP dosages at 10 mg/L were found to inhibit nitrite oxidation in systems with low organic loading. PAA decay was found to be concentration-dependent. It had a considerable negative effect on nitrite oxidation over a prolonged period of time when applied at a dosage ?2 mg/L. PAA and HP decay patterns were significantly affected by water quality parameters, i.e. at low organic matter content HP degradation was impeded due to microbial inhibition. FISH analysis on biofilm samples from two different types of RAS showed that Nitrosomonas oligotropha was the dominant ammonia oxidizing bacteria, whereas abundant nitrite oxidizing bacteria consisted of Nitrospira spp. In conclusion, measures to reduce FA have been documented, and investigations of HP and PAA have reflected a relatively narrow safety margin when applied to biofilters

Pedersen, Lars-Flemming

2009-01-01

37

Use of planted biofilters in integrated recirculating aquaculture-hydroponics systems in the Mekong Delta, Vietnam  

DEFF Research Database (Denmark)

The feasibility of using planted biofilters for purification of recirculated aquaculture water in the Mekong Delta of Vietnam was assessed. The plant trenches were able to clean tilapia aquaculture water and to maintain good water quality in the fish tanks without renewal of the water. NH4-N was removed efficiently in the plant trenches, particularly in the trenches with Canna glauca L., probably because of plant uptake and nitrification-denitrification. Plant uptake constituted 6% of N and 7% of P in the input feed. Approximately 1.0 m3 of water was needed per kg of fish produced, and 370, 97 and 2842 g fresh aboveground biomass of Ipomoea aquatica Forssk., Lactuca sativa L. and C. glauca, respectively, were produced. The leafy vegetables provide some extra income besides fish products, whereas C. glauca provides nice flowers and contributes to a significant nutrient removal with annual uptake rates of 725 kg N and 234 kg P ha-1 year-1. This research demonstrates that integrated recirculating aquaculture-hydroponics (aquaponics) systems provide significant water savings and nutrient recycling as compared with traditional fish ponds. © 2012 John Wiley & Sons Ltd.

Trang, N.T.D.; Brix, Hans

2014-01-01

38

Application and analytical verification of peracetic acid use in different types of freshwater aquaculture systems  

DEFF Research Database (Denmark)

Peracetic acid (PAA) is a highly reactive peroxygen compound with wide-ranging antimicrobial effects. PAA has recently gained substantial attention, due to additional beneficial attributes such as easily degradability and harmless disinfection byproducts. However, PAA is only sporadically used by the aquaculture industry as it is difficult to apply in correct dosages. This study describes the degradation kinetics of PAA when used as an aquaculture disinfectant. Effects of temperature, organic matter content and initial PAA dosage on the chemical fate of PAA is reported. Furthermore, investigations of water sanitation with PAA application were used to analytically verify actual PAA concentration under real conditions at different kinds of aquaculture systems. A characteristic instant disinfection demand was found to be significantly positively related to water COD content, and PAA half-lives were found to be in the order of a few minutes. The study revealed that PAA degrades so rapidly that insufficient disinfection is a likely outcome. The observations have applications for optimizing water treatment strategies with PAA. The investigations also indicated that the rapid degradation and hence swift presence of PAA in RAS made raceway disinfection possible without bypassing the biofilters. Future perspectives, benefits and drawbacks on the use of PAA in RAS are discussed

Pedersen, Lars-Flemming

2011-01-01

39

Electronics and electronic systems  

CERN Document Server

Electronics and Electronic Systems explores the significant developments in the field of electronics and electronic devices. This book is organized into three parts encompassing 11 chapters that discuss the fundamental circuit theory and the principles of analog and digital electronics. This book deals first with the passive components of electronic systems, such as resistors, capacitors, and inductors. These topics are followed by a discussion on the analysis of electronic circuits, which involves three ways, namely, the actual circuit, graphical techniques, and rule of thumb. The remaining p

Olsen, George H

1987-01-01

40

Long term/low dose formalin exposure to small-scale recirculation aquaculture systems  

DEFF Research Database (Denmark)

Repetitive long term formalin application at low dose was investigated to determine the effect on formaldehyde removal rate, biofilter nitrification and the microbial composition in small-scale recirculation aquaculture biofilters. Six pilot-scale recirculation aquaculture systems holding rainbow trout (Oncorhynchus mykiss) were designated to formalin treatments (C-0 at 10 and 20mg/L formaldehyde) on a daily or weekly basis. Formaldehyde removal rates were measured over 10 weeks, during which biofilter nitrification rates were measured in terms of standardized NH4Cl spiking events. The rates were positively correlated to the amount and frequency of formalin treatment. In systems with regularly low formalin dosage, the formaldehyde removal rate increased up to tenfold from 0.19 +/- 0.05 to 1.81 +/- 0.13 mg/(L h). Biofilter nitrification was not impaired in systems treated with formalin on a daily basis as compared to untreated systems. In systems intermittently treated with formalin, increased variation and minor reductions of ammonium and nitrite oxidation rates were observed. Nitrifying bacteria were screened by specific gene probes using fluorescence in situ hybridization and quantified by digital image analysis. The relative abundance of ammonia-oxidizing bacteria (AOB) was up to 5.4% of all Bacteria (EUB) positive cells, predominantly Nitrosomonas oligotropha. Nitrite-oxidizing bacteria (NOB), mainly consisting of Nitrospira sp. were found in all biofilm samples up to 2.9%, whereas Nitrobacter sp. was not detected. The relative abundances of AOB and NOB in the untreated system were generally higher compared to the system exposed to formalin. Low dose formalin in recirculated aquaculture systems proved to be a possible treatment strategy, as the effect on nitrification was minimal. Since formaldehyde was steadily removed by microorganisms, available biofilter surface area, hydraulic retention time a:id temperature can be used to predict removal and hence estimate e.g. effluent concentration, (C) 2009 Elsevier B.V. All rights reserved.

Pedersen, Lars-Flemming; Pedersen, Per Bovbjerg

2010-01-01

41

Background paper on aquaculture research  

DEFF Research Database (Denmark)

The Board of MISTRA established in 2012 a Working Group (WG) on Aquaculture to provide the Board with background information for its upcoming decision on whether the foundation should invest in aquaculture research. The WG included Senior Advisor Axel Wenblad, Sweden (Chairman), Professor Ole Torrissen, Norway, Senior Advisory Scientist Unto Eskelinen, Finland and Senior Advisory Scientist Alfred Jokumsen, Denmark. The WG performed an investigation of the Swedish aquaculture sector including interviews with a range of stakeholders within aquaculture research, farming organisations, authorities, NGOs and the Ministry of Rural Affairs. The term aquaculture corresponds to the Swedish term Vattenbruk. Aquaculture is the cultivation of fish, shellfish or plants in fresh water (FW) or sea water (SW). Aquaculture has become the fastest growing food producing sector currently producing totally about 80 million tonnes accounting for close to 50 % of all aquatic food destined for the global human consumption. The Swedish aquaculture production currently includes about 11,000 tonnes rainbow trout in FW and SW, 1,100 tonnes arctic char (FW), 90 tonnes eel (FW), 1,500 tonnes mussels (SW) and a few tonnes of crayfish altogether corresponding to a total value of SEK 328 million in 2011. Further about 1,000 tonnes of fish and crustaceans were produced for restocking as well as about 3 million fry of salmon and trout were released into rivers. Swedish aquaculture research was overall assessed to be of very high quality and highly acknowledged at international level. However, integration of the research issues with the main stakeholders in the aquaculture sector needs focus; i.e. integration of the political frameworks, regional administrations, the aquaculture producers and the research groups on aquaculture. A closer connection and dialogue between the stakeholders may be facilitated through the regional aquaculture centres interconnected through the National Competence Centre for Aquaculture, and the National Aquaculture Council being established. These structures may create a common and focused platform for cooperation on research and education, exchange and transfer of knowledge from research to aquaculture practice. Further, integration of biological and technological research combined with education and training of skilled professionals as well as authority staff dealing with aquaculture is strongly called upon. Hence, a strong integration of the stakeholders within the aquaculture sector is assessed to be an important platform for a trans-disciplinary research and development program for strategic and efficient development of Swedish Aquaculture. Sweden has large potentials for aquaculture due to the availability of vast water resources of good quality (both marine and fresh water), a high veterinary status and generally well developed public infrastructure. Swedish aquaculture has the potential to develop into a green business producing environmentally sustainable healthy food with low ecosystem and climate impact. Swedish import of aquaculture products may be reduced by increased domestic production. Further Swedish aquaculture may be a driving force in the development of employment, infrastructures and improvement of economic and social conditions in rural areas. Swedish 4 • mistra aquaculture has the potential to contribute significantly to food security. It is therefore important that aquaculture becomes an integrated part of the food production system, i.e. being accepted as an equal food producing sector in line with the agricultural sector.Innovative development of Swedish aquaculture requires production systems with minimal environmental impact, e.g. recirculation technology, efficient feeds and waste management. Although the nutrient-poor hydropower dams in northern Sweden may tolerate nutrient load the strategy for the required development of Swedish aquaculture has to include technologies and strategies to minimize the environmental impact, in particular to the Baltic Sea. Swedish aquaculture may develop to be an env

Wenblad, Axel; Jokumsen, Alfred

2013-01-01

42

The OMEGA system for marine bioenergy, wastewater treatment, environmental enhancement, and aquaculture  

Science.gov (United States)

OMEGA is an acronym for Offshore Membrane Enclosure for Growing Algae. The OMEGA system consists of photobioreactors (PBRs) made of flexible, inexpensive clear plastic tubes attached to floating docks, anchored offshore in naturally or artificially protected bays [1]. The system uses domestic wastewater and CO2 from coastal facilities to provide water, nutrients, and carbon for algae cultivation [2]. The surrounding seawater maintains the temperature inside the PBRs and prevents the cultivated (freshwater) algae from becoming invasive species in the marine environment (i.e., if a PBR module accidentally leaks, the freshwater algae that grow in wastewater cannot survive in the marine environment). The salt gradient between seawater and wastewater is used for forward osmosis (FO) to concentrate nutrients and facilitate algae harvesting [3]. Both the algae and FO clean the wastewater, removing nutrients as well as pharmaceuticals and personal-care products [4]. The offshore infrastructure provides a large surface area for solar-photovoltaic arrays and access to offshore wind or wave generators. The infrastructure can also support shellfish, finfish, or seaweed aquaculture. The economics of the OMEGA system are supported by a combination of biofuels production, wastewater treatment, alternative energy generation, and aquaculture. By using wastewater and operating offshore from coastal cities, OMEGA can be located close to wastewater and CO2 sources and it can avoid competing with agriculture for water, fertilizer, and land [5]. By combining biofuels production with wastewater treatment and aquaculture, the OMEGA system provides both products and services, which increase its economic feasibility. While the offshore location has engineering challenges and concerns about the impact and control of biofouling [6], large OMEGA structure will be floating marine habitats and will create protected 'no-fishing' zones that could increase local biodiversity and fishery productivity. Potential test sites for the next phase of OMEGA (1-hectare integrated system) will be discussed.

Trent, J. D.

2013-12-01

43

Analysis of river basin of Piarg aquaculture system  

International Nuclear Information System (INIS)

In this paper the system of dams near vicinity Piarg (on the present Stiavnicke Bane, the Slovak Republic) which was constructed in 18thcentury for drainage of underground mines is described. Basin and water captured by dams are analysed and produced power is calculated. This Piarg system of ponds was capable to produce about 173 kW of power that has spared work of 940 horses in 4 shift operation.

44

Program to monitor and evaluate a passive solar greenhouse/aquaculture system. Final report  

Energy Technology Data Exchange (ETDEWEB)

A temperature monitoring program of Amity's solar greenhouse demonstrated that air, soil, and water temperatures can be maintained at optimal levels without supplemental heat. A foil reflector placed in front of the greenhouse glazing at an angle of between 0 and 5/sup 0/ above horizontal enhanced direct light entering the greenhouse by as much as 22%. Aquaculture in the water heat storage of a solar greenhouse has been a success. Fish reached harvest size in about seven months. The two species that were received the best by the public were African perch (Tilapia mossambica) and channel catfish (Ictalurus punctatus). Although carp (Cyprinus carpio) were the fastest growers they were not well received by the public. Linking hydroponics to greenhouse aquaculture shows a lot of promise. Different support medias were examined and tomatoes and European cucumbers were raised successfully. A savonius windmill was successfully linked to an aquaculture aeration system but because of the wind pattern in the Willamette valley the windmill system did not provide air in the evening when it was needed most. Alternate designs are discussed. Locally grown fish diets were evaluated for their ability to promote fish growth. Diets such as water hyacinth, duckweed, earthworms, beans, and comfrey were raised on the Amity site, pelleted with a hand grinder and solar dried. Duckweed and earthworms appear to hold promise for a nutritous, easy to grow and pelletize, food source. Amity's solar greenhouse, three coldframe designs and a PVC tunnel cloche were compared in a vegetable growing trial. Most impressive was the cloche design because it provided adequate protection, was inexpensive and very easy to build.

1982-01-01

45

Aquaculture Network Information Center (AquaNIC)  

Science.gov (United States)

Links to national and international level electronic resources for aquaculture information including: scientific institutions, agencies, industries, news, newsletters, job listings, discussion groups, courses, species, publications, and commercial products. Goals include: providing self-paced aquaculture instruction to the aquaculture industry, and obtaining user input in directing AquaNIC services. A version in Spanish is being prepared.

46

The formation of a risk management system for projects in the field of aquaculture innovative development in the Kaliningrad region: a case study  

Directory of Open Access Journals (Sweden)

Full Text Available This article sets out to develop the concept and the principal scheme of the formation of a risk management system for innovative economic development projects in the field of aquaculture. The research carried out by the authors helps identify the main problems and characteristics of risk management projects for the development of aquaculture in presentday Russia. The authors outline the status and features of aquaculture development projects in the North-western federal district and the Kaliningrad region. The article formulates and justifies the concept of “risk management projects in innovative development of aquaculture in the region” focusing on the classification of aquaculture risks in relation to innovative development projects, which expands the conceptual framework of risk management in view of the specific risks relating to economic development projects in the field of aquaculture. The authors characterize modern methods and approaches to risk management projects and organizations in the context of their application in the framework of aquaculture development projects and offer mechanisms for risk management of aquaculture development projects, which make it possible to include risk management activity in the general context of activities of parent project organizations. The authors develop the concept and principal scheme of the formation of risk management system for innovative development projects in aquaculture.

Serbulov A. V.

2012-01-01

47

Abundance, diversity and seasonal dynamics of predatory bacteria in aquaculture zero discharge systems.  

Science.gov (United States)

Standard aquaculture generates large-scale pollution and strains water resources. In aquaculture using zero discharge systems (ZDS), highly efficient fish growth and water recycling are combined. The wastewater stream is directed through compartments in which beneficial microbial activities induced by creating suitable environmental conditions remove biological and chemical pollutants, alleviating both problems. Bacterial predators, preying on bacterial populations in the ZDS, may affect their diversity, composition and functional redundancy, yet in-depth understanding of this phenomenon is lacking. The dynamics of populations belonging to the obligate predators Bdellovibrio and like organisms (BALOs) were analyzed in freshwater and saline ZDS over a 7-month period using QPCR targeting the Bdellovibrionaceae, and the Bacteriovorax and Bacteriolyticum genera in the Bacteriovoracaeae. Both families co-existed in ZDS compartments, constituting 0.13-1.4% of total Bacteria. Relative predator abundance varied according to the environmental conditions prevailing in different compartments, most notably salinity. Strikingly, the Bdellovibrionaceae, hitherto only retrieved from freshwater and soil, also populated the saline system. In addition to the detected BALOs, other potential predators were highly abundant, especially from the Myxococcales. Among the general bacterial population, Flavobacteria, Bacteroidetes, Fusobacteriaceae and unclassified Bacteria dominated a well mixed but seasonally fluctuating diverse community of up to 238 operational taxonomic units, as revealed by 16S rRNA gene sequencing. PMID:24749684

Kandel, Prem P; Pasternak, Zohar; van Rijn, Jaap; Nahum, Ortal; Jurkevitch, Edouard

2014-07-01

48

Peracetic acid degradation in freshwater aquaculture systems and possible practical implications  

DEFF Research Database (Denmark)

Peracetic acid (PAA) is a highly reactive peroxygen compound with wide-ranging antimicrobial effects and is considered an alternative sanitizer to formaldehyde. Products containing PAA are available in solution with acetic acid and hydrogen peroxide to maintain the stability of the chemical, and it decays rapidly when applied to freshwater in aquaculture systems. The rapid decay is beneficial in an environmental context but a challenge to aquaculturists. To assess the impact of organic matter content and temperature on PAA decay, twenty-four batch experiments were set up using PAA doses ranging from 0 to 2.0 mg/l. The results revealed that increasing organic matter content significantly facilitated PAA decay, and positive temperature-decay correlations were found. Instantaneous PAA consumption above 0.2 mg/l was observed, and PAA half-lives were found to be in the order of a few minutes. The relative PAA recovery, calculated as measured PAA concentration over time compared to the PAA concentration applied, decreased with declining dose. Measurements of PAA residuals during water treatment scenarios at three different freshwater fish farms revealed moderate to substantial PAA consumption, documenting a large discrepancy between delivered quantities and realized residuals. Recent investigations of PAA application to manage parasitic diseases in aquaculture are briefly reviewed, and practical implication and guidelines are addressed

Pedersen, Lars-Flemming; Meinelt, Thomas

2013-01-01

49

Recirculating aquaculture system for high density production of the calanoid copepod Acartia tonsa (Dana)  

DEFF Research Database (Denmark)

The calanoid copepod Acartia tonsa (Dana) is one of the most promising copepod species for marine larviculture. This species has a wide tolerance to temperature and salinity, small size, can produce resting eggs. All their nauplii, copepodites and adults can be use as excellent feeds for marine fish larvae. Yet, the biomass and egg production of A. tonsa has been limited mainly due to the challanges to culture them at high density. The development of recirculating aquaculture system (RAS) in recent decades has opened a new culturing system that is expected to provide more stable environmental conditions to favor the production of A. tonsa at high density. The current study was initiated to preliminarily apply a recircultating aquaculture system (RAS) for A. tonsa production. A flow through aquaculture system (FTAS) was also run in parallel to evaluate the capacity of RAS compared to the FTAS. Both RAS and FTAS (3 replicates per system) were set up in the same room to ensure the equal condition. The initial densities of copepods were 20000 nauplii L-1 for investigation of growth and development in the early phase and 5000 ind L-1 in the copepodite and adult stages for testing reproduction capacity. A. tonsa fed the unicellular algae Rhodomonas baltica were registered for four weeks in triplicate 50 L tanks in each system. Water quality parameters were recorded daily for temperature, oxygen, pH, salinity, particles and every five days for nitrogenous waste and bacteria through the experimental period in both systems. Unexpectedly, the hatching ratio of eggs was lower in RAS compared to FTAS that may be explained by a higher concentration of nitrite, nitrate and bacteria including Vibrio spp., haemolytic bacteria and fast growing bacteria. A. tonsa cultured in both RAS and FTAS had the similar survival, growth, and reproduction, yet the nauplii developed into copepodites faster in RAS (110h) compared to FTAS (158h). This can be an indication for the potential for culturing or maintaining A. tonsa nauplii and early copepodite stages at higher densities before feeding larvae of marine species. The RAS also needs a further optimisation of water quality by a denitrifying filter component to stabilize for copepod cultivation and an implementation of disease control treatment is also required.

Vu, Minh Thi Thuy; Øie, Gunvor

50

A ZigBee Wireless Sensor Network for Monitoring an Aquaculture Recirculating System  

Scientific Electronic Library Online (English)

Full Text Available SciELO Mexico | Language: English Abstract in spanish Se desarrolló una red de sensores inalámbrica con el protocolo ZigBee para monitorear un sistema experimental acuícola con recirculación de agua. La red incluye sensores de temperatura, oxígeno disuelto, presión de agua y aire, así como de corriente eléctrica. La alta densidad de organismos requerid [...] a para que estos sistemas sean económicamente viables nos presentan un caso donde las redes de sensores pueden ser aplicadas para preservar un stock de peces saludable reduciendo las probabilidades de fallas que conlleven pérdidas en la producción. Se desarrollaron y probaron módulos para la toma y transmisión de datos a través de una red ZigBee y se implementaron en una granja acuícola experimental. Se desarrolló un programa de monitoreo para desplegar los valores de los sensores y emitir alertas cuando se rebasen los límites de referencia especificados. Una alerta por medio de un mensaje SMS y un correo electrónico pueden ser emitidas. Una interfase WEB permite el acceso a los valores de los sensores. El presente trabajo demuestra la aplicabilidad de las redes inalámbricas ZigBee al monitoreo de sistemas acuícolas. Abstract in english A ZigBee wireless sensor network was developed for monitoring an experimental aquaculture recirculating system. Temperature, dissolved oxygen, water and air pressure as well as electric current sensors were included in the setup. The high fish densities required in these systems to become economical [...] ly viable present a case where sensor networks can be applied to preserve a healthy livestock and to reduce the risk of failures that end up in the loss of production. Modules for reading and transmitting sensor values through a ZigBee wireless network were developed and tested. The modules were installed in an aquaculture recirculating system to transmit sensor values to the network coordinator. A monitoring program was created in order to display and store sensor values and to compare them with reference limits. An alert is emitted in case reference limits have been reached. E-mail and an SMS message alert can also be sent to the cellular phone of the system administrator, so immediate action can be taken. A web interface allows Internet access to the sensor values. The present work demonstrates the applicability of ZigBee wireless sensor network technology to aquaculture recirculating systems.

Francisco J., Espinosa-Faller; Guillermo E., Rendón-Rodríguez.

2012-12-01

51

The potential use of constructed wetlands in a recirculating aquaculture system for shrimp culture  

International Nuclear Information System (INIS)

Constructed wetlands improved water qualities and consequently increased the shrimp growth and survival in a recirculating system. - A pilot-scale constructed wetland unit, consisting of free water surface (FWS) and subsurface flow (SF) constructed wetlands arranged in series, was integrated into an outdoor recirculating aquaculture system (RAS) for culturing Pacific white shrimp (Litopenaeus vannamei). This study evaluated the performance of the wetland unit in treating the recirculating wastewater and examined the effect of improvement in water quality of the culture tank on the growth and survival of shrimp postlarvae. During an 80-day culture period, the wetland unit operated at a mean hydraulic loading rate of 0.3 m/day and effectively reduced the influent concentrations of 5-day biochemical oxygen demand (BOD5, 24%), suspended solids (SS, 71%), chlorophyll a (chl-a, 88%), total ammonium (TAN, 57%), nitrite nitrogen (NO2-N, 90%) and nitrate nitrogen (NO3-N, 68%). Phosphate (PO4-P) reduction was the least efficient (5.4%). The concentrations of SS, Chl-a, turbidity and NO3-N in the culture tank water in RAS were significantly (P?0.05) lower than those in a control aquaculture system (CAS) that simulated static pond culture without wetland treatment. However, no significant difference (P?0.05) in BOD5, TAN and NO2-N was found between the two systems. At the end of the study, the harvess. At the end of the study, the harvest results showed that shrimp weight and survival rate in the RAS (3.8±1.8 g/shrimp and 90%) significantly (P?0.01) exceeded those in the CAS (2.3±1.5 g/shrimp and 71%). This study concludes that constructed wetlands can improve the water quality and provide a good culture environment, consequently increasing the shrimp growth and survival without water exchange, in a recirculating system

52

BIOFILTERS IN AQUACULTURE  

Directory of Open Access Journals (Sweden)

Full Text Available Recirculating aquaculture is one of the solutions to an environmentally sustainable and economically feasible aquaculture production, and can be established in either urban or rural communities. Controlled conditions enable optimal growth conditions suitable for the species in question during the whole growth process, as well as the shortening of the process itself, when compared to open uncontrolled systems. Recirculating systems are now one of the most researched fields of aquaculture, and biofiltration as the reduction of the poisonous ammonia compounds generated by digestion of proteins, is one of its most important parts. The aim of this study was to stress the importance of biofiltration, and to describe different designs of biofilters. Many biofilters are being used in commercial and research aquaculture facilities with differences in choice of working organism, design, material, price and etc. For the proper choice of biofilter it is necessary to know characteristics of each recirculating aquaculture system, because there are still no strict criteria for categorizing and applying different biofilter designs.

Ivo Šari?

2010-07-01

53

Low-dose hydrogen peroxide application in closed recirculating aquaculture systems  

DEFF Research Database (Denmark)

The aim of the present work was to simulate water treatment practices with hydrogen peroxide (HP) in recirculating aquaculture systems (RAS). Six identical 1,700-L pilot-scale RAS were divided into two experimental groups based on daily feed allocation and operated under constant conditions for a period of 3 months. The organic and nitrogenous loadings of the systems differed fourfold between the two groups and were achieved by predefined constant daily feed loads and constant additions of water. The fixed cumulative feed burden was 1.6 × 103 mg feed/L in the low-intensity RAS and 6.3 × 103 mg/L in the high-intensity RAS. The decay of HP in rearing tanks and disconnected biofilter units was investigated by means of HP spiking experiments. The decay in high-intensity RAS rearing units and biofilters was orders of magnitude faster than that in low-intensity units. The application of HP impaired biofilter nitrite oxidation in low-intensity RAS but not in high-intensity RAS. The impact of HP exposure time on biofilter nitrification capacity was then assessed in biofilter bench-scale experiments with nitrite spiking. Exposure time was found to significantly affect nitrite oxidation. Compared with unexposed biofilter elements, nitrite oxidation was reduced more than 90% following 3 h of exposure to 15 mg HP/L, whereas 30 min of exposure had only minor negative effects on nitrite oxidation. The findings of this study demonstrate the potential for developing HP water treatment practices for RAS and contradict prevailing notions that HP cannot be used safely in RAS that employ biofiltration. The development of effective new HP treatment protocols for recirculating aquaculture could reduce the current dependence on formalin to improve water quality and control parasitic loads

Pedersen, Lars-Flemming; Good, C.

2012-01-01

54

Nitrogen and Phosphorus Removal in the Recirculating Aquaculture System with Water Treatment Tank containing Baked Clay Beads and Chinese Cabbage  

OpenAIRE

This research aims to describe the nitrogen and phosphorus removal in Recirculating Aquaculture System (RAS) by crop plants biomass production. The 3 experiment systems consisted of 1 treatment (fish tank + baked clay beads + Chinese cabbage) and 2 controls as control-1 (fish tank only) and control-2 (fish tank + baked clay beads), were performed. With all experimental RAS, Nile tilapia (Oreochromis niloticus) was cultured at 2 kg/m3 density. The baked clay beads (8-16 mm in diameter) were fi...

Aeknarin Thanakitpairin; Wiboonluk Pungrasmi; Sorawit Powtongsook

2014-01-01

55

Nutrient Discharge from aquaculture operations in function of system design and production enviorment (Online first)  

OpenAIRE

In aquaculture, nutrient loading is defined as the difference between nutrients supplied with fertilizers and feed and nutrients harvested in the form of finfish, crustaceans, molluscs and seaweeds. On average, the production of finfish and crustaceans results in a net nutrient loading, while for the production of molluscs and seaweeds the nutrient loading is negative. In marine and brackish water aquaculture, on a global scale, more nutrients are extracted than added to the environment. Howe...

Verdegem, M. C. J.

2013-01-01

56

Aquaculture Information Package  

Energy Technology Data Exchange (ETDEWEB)

This package of information is intended to provide background to developers of geothermal aquaculture projects. The material is divided into eight sections and includes information on market and price information for typical species, aquaculture water quality issues, typical species culture information, pond heat loss calculations, an aquaculture glossary, regional and university aquaculture offices and state aquaculture permit requirements.

Boyd, T.; Rafferty, K. [editors

1998-01-01

57

Enhancing the resilience of inland fisheries and aquaculture systems to climate change  

Directory of Open Access Journals (Sweden)

Full Text Available Some of the most important inland fisheries in the World are found in semi-arid regions. Production systems and livelihoods in arid and semi-arid areas are at risk from future climate variability and change; their fisheries are no exception. This paper reviews the importance of fisheries to livelihoods in ‘wetlands in drylands’, with a focus on case-studies in Africa. We examine the threats posed by climate change to the traditional ‘tri-economy’ of fishing, farming and livestock herding. Although both livelihood strategies and local institutions are highly adapted to cope with, and benefit from, climate-induced variability, weaknesses in the wider governance and macro-economic environment mean that the overall adaptive capacity of these regions is low and the farmer-herder-fishers are vulnerable to projected climate change. In order to maintain the important nutritional, economic, cultural and social benefits of fisheries in the face of climate change, planned adaptation at scales from the local to the regional (trans-national is required. We use the concept of resilience in linked social-ecological systems to examine how such responses may be developed and promoted. Key strategies include facilitating people’s geographical and occupational mobility, improving intersectoral water and land-use planning, and promoting forms of aquaculture that help build resilience of farming systems to seasonal and episodic water deficits.

Edward H Allison

2007-12-01

58

Potential and limitations of ozone in marine recirculating aquaculture systems - Guidelines and thresholds for a safe application  

OpenAIRE

The aim of the present thesis was to assess the potential and limitations of ozonation in marine recirculating aquaculture systems (RAS) while particularly focussing on the toxicity, formation and removal of ozone-produced oxidants (OPO) in order to develop guidelines and thresholds for a reasonable and safe ozone application. In the first two chapters the toxicity of OPO was investigated for Pacific white shrimp (Litopenaeus vannamei) and turbot (Psetta maxima) and maximum safe exposure leve...

Schro?der, Jan

2011-01-01

59

Managing sea cucumber fisheries and aquaculture : Studies of social-ecological systems in the Western Indian Ocean  

OpenAIRE

Collecting sea cucumbers to supply the high value Chinese dried seafood market is a livelihood activity available to many people in the Western Indian Ocean (WIO), making it an important part of local economies. These fisheries are generally not successfully managed and tropical sea cucumber fisheries show continuing signs of decline. This thesis takes a social-ecological systems approach to guide better management of sea cucumber fisheries and aquaculture in the WIO. Papers 1 and 2 analyse t...

Eriksson, Hampus

2012-01-01

60

Total ammoniacal nitrogen biofiltration of wastewaters from aquaculture systems using Macrocystis spp.  

Science.gov (United States)

The results of total ammoniacal nitrogen (NH(3) + NH(4) (+)) removal in aquaculture systems using two experimental sets, aquatic seedlings produced in laboratory controlled conditions and wild seaweed (Macrocystis spp.) in reproductive state, are shown in this work. Biofiltration assays were carried out using a load of total ammoniacal nitrogen (TAN) of 1 mg/L. Absorption rates were measured taking into account a previous surface characterization, which gave values of 44 ± 14 cm(2)/g and 18 ± 6 cm(2)/g for aquatic seedlings and wild algae, respectively. The following parameters were measured during the experimental runs: temperature, pH, O(2), illuminance or light intensity, salinity and total solids. TAN removals of 61% and 70% were achieved for the seedlings and Macrocystis spp., respectively, after 17 h of treatment. The TAN absorption results were expressed as a function of surface and mass achieving the following values: 3.0 nmol N cm(-2) h(-1) and 111 nmol N g(-1) h(-1) for the seedlings, and 6.9 nmol N cm(-2) h(-1) and 122.4 nmol N g(-1) h(-1) for the macroalgae. In the light of these biofiltration processes, the initial TAN concentration decreased by 90% for the seedlings and wild algae over approximately 110 and 41 h, respectively. In addition, TAN removals achieved with Macrocystis spp. were always higher than those obtained with aquatic seedlings for the same operating periods. PMID:23379944

Bravo, R; Segovia, E; Guerrero, L; Montalvo, S; Barahona, A; Borja, R

2013-01-01

61

An optimized and simplified method for analysing urea and ammonia in freshwater aquaculture systems  

DEFF Research Database (Denmark)

This study presents a simple urease method for analysis of ammonia and urea in freshwater aquaculture systems. Urea is hydrolysed into ammonia using urease followed by analysis of released ammonia using the salicylate-hypochlorite method. The hydrolysis of urea is performed at room temperature and without addition of a buffer. A number of tests were performed on water samples obtained from a commercial rainbow trout farm to determine the optimal urease concentration and time for complete hydrolysis. One mL of water sample was spiked with 1.3 mL urea at three different concentrations: 50 lg L 1, 100 lg L 1 and 200 lg L 1 urea-N. In addition, five concentrations of urease were tested, ranging from 0.1 U mL 1 to 4 U mL 1. Samples were hydrolysed for various time periods ranging from 5 to 120 min. A urease concentration of 0.4 U mL 1 and a hydrolysis period of 120 min gave the best results, with 99.6–101% recovery of urea-N in samples spiked with 100 or 200 lg L 1 urea-N. The level of accurate quantification of ammonia using the method is 50 lg L 1 NH4 +-N, and the detection level is 5–10 lg L 1 NH4 +-N

Larsen, Bodil Katrine; Dalsgaard, Anne Johanne Tang

2013-01-01

62

An integrated closed system for fish-plankton aquaculture in Amazonian fresh water.  

Science.gov (United States)

A prototype of an integrated closed system for fish-plankton aquaculture was developed in Iquitos (Peruvian Amazonia) in order to cultivate the Tiger Catfish, Pseudoplatystoma punctifer (Castelnau, 1855). This freshwater recirculating system consisted of two linked sewage tanks with an intensive rearing unit (a cage) for P. punctifer placed in the first, and with a fish-plankton trophic chain replacing the filters commonly used in clear water closed systems. Detritivorous and zooplanktivorous fishes (Loricariidae and Cichlidae), maintained without external feeding in the sewage volume, mineralized organic matter and permitted the stabilization of the phytoplankton biomass. Water exchange and organic waste discharge were not necessary. In this paper we describe the processes undertaken to equilibrate this ecosystem: first the elimination of an un-adapted spiny alga, Golenkinia sp., whose proliferation was favored by the presence of a small rotifer, Trichocerca sp., and second the control of this rotifer proliferation via the introduction of two cichlid species, Acaronia nassa Heckel, 1840 and Satanoperca jurupari Heckel, 1840, in the sewage part. This favored some development of the green algae Nannochloris sp. and Chlorella sp. At that time we took the opportunity to begin a 3-month rearing test of P. punctifer. The mean specific growth rate and feed conversion ratio (FCR) of P. punctifer were 1.43 and 1.27, respectively, and the global FCR, including fish in the sewage part, was 1.08. This system has proven to be suitable for growing P. punctifer juveniles out to adult, and provides several practical advantages compared with traditional recirculating clear water systems, which use a combination of mechanical and biological filters and require periodic waste removal, leading to water and organic matter losses. PMID:24849417

Gilles, S; Ismiño, R; Sánchez, H; David, F; Núñez, J; Dugué, R; Darias, M J; Römer, U

2014-05-22

63

Identification of Bacterial Community Composition in Freshwater Aquaculture System Farming of Litopenaeus vannamei Reveals Distinct Temperature-Driven Patterns  

Directory of Open Access Journals (Sweden)

Full Text Available Change in temperature is often a major environmental factor in triggering waterborne disease outbreaks. Previous research has revealed temporal and spatial patterns of bacterial population in several aquatic ecosystems. To date, very little information is available on aquaculture environment. Here, we assessed environmental temperature effects on bacterial community composition in freshwater aquaculture system farming of Litopenaeus vannamei (FASFL. Water samples were collected over a one-year period, and aquatic bacteria were characterized by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE and 16S rDNA pyrosequencing. Resulting DGGE fingerprints revealed a specific and dynamic bacterial population structure with considerable variation over the seasonal change, suggesting that environmental temperature was a key driver of bacterial population in the FASFL. Pyrosequencing data further demonstrated substantial difference in bacterial community composition between the water at higher (WHT and at lower (WLT temperatures in the FASFL. Actinobacteria, Proteobacteria and Bacteroidetes were the highest abundant phyla in the FASFL, however, a large number of unclassified bacteria contributed the most to the observed variation in phylogenetic diversity. The WHT harbored remarkably higher diversity and richness in bacterial composition at genus and species levels when compared to the WLT. Some potential pathogenenic species were identified in both WHT and WLT, providing data in support of aquatic animal health management in the aquaculture industry.

Yuyi Tang

2014-08-01

64

End-of-pipe single-sludge denitrification in pilot-scale recirculating aquaculture systems  

DEFF Research Database (Denmark)

A step toward environmental sustainability of recirculat aquaculture systems (RAS) is implementation ofsingle-sludge denitrification, a process eliminating nitrate from the aqueous environment while reduc-ing the organic matter discharge simultaneously. Two 1700 L pilot-scale RAS systems each with a 85 Ldenitrification (DN) reactor treating discharged water and hydrolyzed solid waste were setup to testthe kinetics of nitrate and COD removal. Nitrate removal and COD reduction efficiency was measured attwo different DN-reactor sludge ages (high X: 33–42 days and low X: 17–23 days). Nitrate and total N(NO3?+ NO2?+ NH4+) removal of the treated effluent water ranged from 73–99% and 60–95% during theperiods, respectively, corresponding to an overall maximum RAS nitrate removal of approximately 75%.The specific nitrate removal rate increased from 17 to 23 mg NO3?-N (g TVS d)?1and the maximal poten-tial DN rate (measured at laboratory ideal conditions) increased correspondingly from 64–68 mg NO3?-N(g TVS d)?1to 247–294 mg NO3?-N (g TVS d)?1at high and low X, respectively. Quantification of denitri-fiers in the DN-reactors by qPCR showed only minor differences upon the altered sludge removal practice.The hydrolysis unit improved the biodegradability of the solid waste by increasing volatile fatty acid CODcontent 74–76%. COD reductions in the DN-reactors were 64–70%. In conclusion, this study showed thatsingle-sludge denitrification was a feasible way to reduce nitrate discharge from RAS, and higher DN rateswere induced at lower sludge age/increased sludge removal regime. Improved control and optimizationof reactor DN-activity may be achieved by further modifying reactor design and management scheme asindicated by the variation in and between the two DN-reactors.

Suhr, Karin Isabel; Pedersen, Lars-Flemming

2014-01-01

65

Degradation and effect of hydrogen peroxide in small-scale recirculation aquaculture system biofilters  

DEFF Research Database (Denmark)

From an environmental point of view, hydrogen peroxide (HP) has beneficial attributes compared with other disinfectants in terms of its ready degradation and neutral by-products. The rapid degradation of HP can, however, cause difficulties with regard to safe and efficient water treatment when applied in different systems. In this study, we investigated the degradation kinetics of HP in biofilters from water recirculating aquaculture systems (RAS). The potential effect of HP on the nitrification process in the biofilters was also examined. Biofilter elements from two different pilot-scale RAS were exposed to various HP treatments in batch experiments, and the HP concentration was found to follow an exponential decay. The biofilter ammonia and nitrite oxidation processes showed quick recuperation after exposure to a single dose of HP up to 30 mg L?1. An average HP concentration of 10–13 mg L?1 maintained over 3 h had a moderate inhibitory effect on the biofilter elements from one of the RAS with relatively high organic loading, while the nitrification was severely inhibited in the pilot-scale biofilters from the other RAS with a relatively low organic loading. A pilot-scale RAS, equipped with two biofilter units, both a moving-bed (Biomedia) and a fixed-bed (BIO-BLOK®) biofilter, was subjected to an average HP concentration of ?12 mg L?1 for 3 h. The ammonium- and nitrite-degrading efficiencies of both the Biomedia and the BIO-BLOK® filters were drastically reduced. The filters had not reverted to pre-HP exposure efficiency after 24 h, suggesting a possible long-term impact on the biofilters.

MØller, Martin Sune; Arvin, Erik

2010-01-01

66

Public Health Perspectives on Aquaculture  

OpenAIRE

Nearly half of all seafood consumed globally comes from aquaculture, a method of food production that has expanded rapidly in recent years. Increasing seafood consumption has been proposed as part of a strategy to combat the current non-communicable disease (NCD) pandemic, but public health, environmental, social, and production challenges related to certain types of aquaculture production must be addressed. Resolving these complicated human health and ecologic trade-offs requires systems thi...

Gormaz, Juan G.; Fry, Jillian P.; Erazo, Marcia; Love, David C.

2014-01-01

67

Expanded concept of aquaculture  

OpenAIRE

A new expanded definition of the concept "aquaculture" is offered; according to it aquaculture includes fishery, commercial fishing, processing of hydrobionts and ecology of aquaculture. The general concepts, the structure of aquaculture types and the major theoretical and applied problems are considered.

Melnikov Victor Nickolaevich; Melnikov Alexander Victorovich

2012-01-01

68

Expanded concept of aquaculture  

Directory of Open Access Journals (Sweden)

Full Text Available A new expanded definition of the concept "aquaculture" is offered; according to it aquaculture includes fishery, commercial fishing, processing of hydrobionts and ecology of aquaculture. The general concepts, the structure of aquaculture types and the major theoretical and applied problems are considered.

Melnikov Victor Nickolaevich

2012-11-01

69

Aquaculture information package  

Energy Technology Data Exchange (ETDEWEB)

This package of information is intended to provide background information to developers of geothermal aquaculture projects. The material is divided into eight sections and includes information on market and price information for typical species, aquaculture water quality issues, typical species culture information, pond heat loss calculations, an aquaculture glossary, regional and university aquaculture offices and state aquaculture permit requirements. A bibliography containing 68 references is also included.

Boyd, T.; Rafferty, K.

1998-08-01

70

Effect of oxidation–reduction potential on performance of European sea bass (Dicentrarchus labrax) in recirculating aquaculture systems  

OpenAIRE

The direct impact of oxidation–reduction potential (ORP) on fish welfare and water quality in marine recirculating aquaculture systems (RAS) is poorly documented. In this study, the effects of the fish size (S1, S2, S3) and ORP level (normal, four successive levels) on the performance of European sea bass (Dicentrarchus labrax) were investigated. Three size fish were distributed into two RAS (RAS and RAS O3). Ozone was injected into RAS O3 to increase the ORP level. The ORP was stabilized t...

Li, Xian; Blancheton, Jean-paul; Liu, Ying; Triplet, Sebastien; Michaud, Luigi

2014-01-01

71

Osnovy formirovanija sistemy upravlenija riskami proektov innovacionnogo razvitija akvakul'tury v regione (Na primere Kaliningradskoj oblasti) [The formation of a risk management system for projects in the field of aquaculture innovative development in the Kaliningrad region: a case study  

OpenAIRE

This article sets out to develop the concept and the principal scheme of the formation of a risk management system for innovative economic development projects in the field of aquaculture. The research carried out by the authors helps identify the main problems and characteristics of risk management projects for the development of aquaculture in presentday Russia. The authors outline the status and features of aquaculture development projects in the North-western federal district and the Kali...

Serbulov Alexey; Stepanov Alexey; Polyakov Oleg

2012-01-01

72

[Treatment of marine-aquaculture effluent by the multi-soil-layer (MSL) system and subsurface flow constructed wetland].  

Science.gov (United States)

To evaluate the feasibility of using multi-soil-layer (MSL) system and subsurface flow constructed wetland to treat the wastewater of marine cultured Penaeus vannamei and to determine the suitable process for the local aquaculture wastewater pollution characteristics. In this study, MSL system and four constructed wetland systems with Spartina anglica, Phragmites australis, Typha latifolia and unplanted system were evaluated for their potentials of pollutants removal capacity. The results showed the average removal rates of chemical oxygen demand (COD), total phosphorus (TP), total nitrogen (TN), ammonia nitrogen (NH(4)+ -N) and nitrate (NO-(3) -N) by MSL system were 80. 38% ± 2. 14% , 68. 14% ± 3.51% , 40.79% ± 3. 10% , 42. 68% ± 2.90% and 54. 19% ± 5. 15% , respectively. Additionally, the ability of pollutants removal of other four wetland systems decreased in the order: Spartina anglica, Phragmites australis, Typha latifolia and unplanted system. PMID:25518662

Song, Ying; Huang, Yu-ting; Ge, Chuan; Zhang, Hao; Chen, Xin; Zhang, Zhi-jianz; Luo, An-cheng

2014-09-01

73

Osnovy formirovanija sistemy upravlenija riskami proektov innovacionnogo razvitija akvakul'tury v regione (Na primere Kaliningradskoj oblasti [The formation of a risk management system for projects in the field of aquaculture innovative development in the Kaliningrad region: a case study  

Directory of Open Access Journals (Sweden)

Full Text Available This article sets out to develop the concept and the principal scheme of the formation of a risk management system for innovative economic development projects in the field of aquaculture. The research carried out by the authors helps identify the main problems and characteristics of risk management projects for the development of aquaculture in presentday Russia. The authors outline the status and features of aquaculture development projects in the North-western federal district and the Kaliningrad region. The article formulates and justifies the concept of “risk management projects in innovative development of aquaculture in the region” focusing on the classification of aquaculture risks in relation to innovative development projects, which expands the conceptual framework of risk management in view of the specific risks relating to economic development projects in the field of aquaculture. The authors characterize modern methods and approaches to risk management projects and organizations in the context of their application in the framework of aquaculture development projects and offer mechanisms for risk management of aquaculture development projects, which make it possible to include risk management activity in the general context of activities of parent project organizations. The authors develop the concept and principal scheme of the formation of risk management system for innovative development projects in aquaculture.

Serbulov Alexey

2012-01-01

74

Effectiveness of Floating Micro-Bead Bio-Filter for Ornamental Fish in a Re-Circulating Aquaculture System  

Directory of Open Access Journals (Sweden)

Full Text Available Bio-filtration has been widely used in re-circulating aquaculture system to remove waste and to convert toxic ammonia andnitrite into safe end products ornamental fish and other aquatic organisms. However, the study of micro-bead usage as the filter medium has not yet been broadened and thoroughly developed. Therefore, the aim of this study is to construct a biological filter made from polyethylene micro-bead as the filter medium and to analyze its effectiveness in removingwaste as well as in converting the toxic organic matter into stable substances. The bio-filter was constructed under a rotational molding process. The tubes, hoses, and piping were made from polyvinyl chloride (PVC while the fasteners were made from stainless steel and other non-corrosive materials. The effectiveness of this bio-filter was measured by using biochemical oxygen demand (BOD and total suspended solids (TSS analysis. Results indicated that this bio-filter is efficient enough to remove suspended solids and BOD. Therefore, this floating micro-bead bio-filter can be used in aquaculture systems.

R Fadhil

2011-01-01

75

Future prospects for prophylactic immune stimulation in crustacean aquaculture - the need for improved metadata to address immune system complexity.  

Science.gov (United States)

Future expansion of the crustacean aquaculture industry will be required to ensure global food security. However, this expansion must ensure: (a) that natural resources (including habitat use and fish meal) are sustainably exploited, (b) that the socio-economic development of producing nations is safeguarded, and (c) that the challenge presented by crustacean diseases is adequately met. Conventionally, the problem of disease in crustacean aquaculture has been addressed through prophylactic administration of stimulants, additives or probiotics. However, these approaches have been questioned both experimentally and philosophically. In this review, we argue that real progress in the field of crustacean immune stimulants has now slowed, with only incremental advances now being made. We further contend that an overt focus on the immune effector response has been misguided. In light of the wealth of new data reporting immune system complexity, a more refined approach is necessary - one that must consider the important role played by pattern recognition proteins. In support of this more refined approach, there is now a much greater requirement for the reporting of essential metadata. We propose a broad series of recommendations regarding the 'Minimum Information required to support a Stimulant Assessment experiment' (MISA guidelines) to foster new progression within the field. PMID:24796867

Hauton, Chris; Hudspith, Meggie; Gunton, Laetitia

2015-02-01

76

Public, animal, and environmental health implications of aquaculture.  

OpenAIRE

Aquaculture is important to the United States and the world's fishery system. Both import and export markets for aquaculture products will expand and increase as research begins to remove physiologic and other animal husbandry barriers. Overfishing of wild stock will necessitate supplementation and replenishment through aquaculture. The aquaculture industry must have a better understanding of the impact of the "shrouded" public and animal health issues: technology ignorance, abuse, and neglec...

Garrett, E. S.; Dos Santos, C. L.; Jahncke, M. L.

1997-01-01

77

Public Health Perspectives on Aquaculture.  

Science.gov (United States)

Nearly half of all seafood consumed globally comes from aquaculture, a method of food production that has expanded rapidly in recent years. Increasing seafood consumption has been proposed as part of a strategy to combat the current non-communicable disease (NCD) pandemic, but public health, environmental, social, and production challenges related to certain types of aquaculture production must be addressed. Resolving these complicated human health and ecologic trade-offs requires systems thinking and collaboration across many fields; the One Health concept is an integrative approach that brings veterinary and human health experts together to combat zoonotic disease. We propose applying and expanding the One Health approach to facilitate collaboration among stakeholders focused on increasing consumption of seafood and expanding aquaculture production, using methods that minimize risks to public health, animal health, and ecology. This expanded application of One Health may also have relevance to other complex systems with similar trade-offs. PMID:25152863

Gormaz, Juan G; Fry, Jillian P; Erazo, Marcia; Love, David C

2014-01-01

78

Wastewater Utilization for Poly-?-Hydroxybutyrate Production by the Cyanobacterium Aulosira fertilissima in a Recirculatory Aquaculture System?  

Science.gov (United States)

Intensive aquaculture releases large quantities of nutrients into aquatic bodies, which can lead to eutrophication. The objective of this study was the development of a biological recirculatory wastewater treatment system with a diazotrophic cyanobacterium, Aulosira fertilissima, and simultaneous production of valuable product in the form of poly-?-hydroxybutyrate (PHB). To investigate this possible synergy, batch scale tests were conducted under a recirculatory aquaculture system in fiber-reinforced plastic tanks enhanced by several manageable parameters (e.g., sedimentation, inoculum size, depth, turbulence, and light intensity), an adequate combination of which showed better productivity. The dissolved-oxygen level increased in the range of 3.2 to 6.9 mg liter?1 during the culture period. Nutrients such as ammonia, nitrite, and phosphate decreased to as low as zero within 15 days of incubation, indicating the system's bioremediation capability while yielding valuable cyanobacterial biomass for PHB production. Maximum PHB accumulation in A. fertilissima was found in sedimented fish pond discharge at 20-cm culture depth with stirring and an initial inoculum size of 80 mg dry cell weight (dcw) liter?1. Under optimized conditions, the PHB yield was boosted to 92, 89, and 80 g m?2, respectively for the summer, rainy, and winter seasons. Extrapolation of the result showed that a hectare of A. fertilissima cultivation in fish pond discharge would give an annual harvest of ?17 tons dry biomass, consisting of 14 tons of PHB with material properties comparable to those of the bacterial polymer, with simultaneous treatment of 32,640 m3 water discharge. PMID:21984242

Samantaray, Shilalipi; Nayak, Jitendra Kumar; Mallick, Nirupama

2011-01-01

79

Group-selective enrichment and determination of pyrethroid insecticides in aquaculture seawater via molecularly imprinted solid phase extraction coupled with gas chromatography-electron capture detection.  

Science.gov (United States)

Two types of molecularly imprinted polymers (MIPs) for the simultaneous determination of six pyrethroid insecticides have been developed using deltamethrin (D-MIPs) and cypermethrin (C-MIPs) as template molecules. A comparison of the performance of D-MIPs, C-MIPs, and the corresponding non-imprinted polymers (NIPs) were conducted. Stronger group-selective interactions between the C-MIPs and the six pyrethroid insecticides were achieved. The MISPE method based on the C-MIPs displayed higher extraction recoveries (86.4-96.0%) with RSD values ranging from 2.4 to 7.8% for the six pyrethroid insecticides in aquaculture seawater. After the C-MIP cartridge procedure, the limits of detection and quantification for fenvalerate, deltamethrin, cypermethrin, cyfluthrin, and bifenthrin were in the 16.6-37.0 and 55.3-109.1 ng L?¹ ranges, respectively, and 0.68 and 2.26 ?g L?¹ for phenothrin, respectively. The proposed MISPE method coupled with gas chromatography-electron capture detection was successfully used for the determination of the six pyrethroid insecticides in aquaculture seawater. PMID:22265776

Shi, Xizhi; Liu, Jinghua; Sun, Aili; Li, Dexiang; Chen, Jiong

2012-03-01

80

Desarrollo de Sistemas de Vigilancia Tecnológica en la Acuicultura Española / Development of Technological Vigilance Systems in Spanish Aquaculture  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: Spanish Abstract in spanish En este artículo caracterizamos el proceso de vigilancia tecnológica como respuesta empresarial a la necesaria adaptación a entornos turbulentos y como origen de ventajas competitivas. En este sentido realizamos una recensión teórica, un análisis estratégico de la referida vigilancia como herramient [...] a para el desarrollo competitivo de la empresa en sectores involucrados con la investigación, el desarrollo y la innovación (I+D+i), así como una adaptación secuencial al desarrollo de la acuicultura. Sobre dicha base hemos realizado una aplicación al sector de la acuicultura en España, mediante el contraste de tres hipótesis relacionadas con el nivel global de desarrollo de los sistemas, los factores y agentes del entorno y la utilización de fuentes de información, todas ellas a través del programa estadístico SPSS 18. Como conclusión hemos identificado patrones globales para la vigilancia en el sector y especificidades por subsector, actividad, área geográfica o tipo de cultivo. Abstract in english In this paper we characterize the process of technological monitoring like enterprise answer to the necessary adjustment to turbulent environments and like origin of competitive advantages. In this respect we fulfil a theoretical critique, a strategic analysis of the above-mentioned monitoring like [...] tool for the competitive development of the company in sectors involved with the research, development and innovation (R+D+i), as well as a sequential adjustment to the development of aquaculture. On the above mentioned base we have realized an application to the Spanish Aquaculture, by means of the resistance of three hypotheses related to the global level of development of the systems, the factors and agents of the environment and the use of sources of intelligence, all of them through statistical program SPSS 18. Since conclusion we have identified global patterns for the monitoring in the sector and specificities by subsector, activity, geographical area or type of crop.

Francisco Javier, Sánchez Sellero; Montserrat, Cruz González.

2012-10-01

81

Evaluation of osmotic-stress tolerance of rapeseed (Brassica napus L. cultivars in aquaculture system  

Directory of Open Access Journals (Sweden)

Full Text Available This research was performed in 2011 at University of Mohaghegh Ardabili, Iran, to evaluate osmotic-stress tolerance, at seedling stage, of rapeseed (Brassica napus L., as a split plot experiment based on randomized complete blocks design with four replications. Levels of osmotic stress were considered as main factor and twelve rapeseed cultivars were sub-factor, that were evaluated under aquaculture conditions, based on length, volume, area and dry weight of roots, shoot dry weight and biological yield. The results showed that stress levels had signification effect on studied traits (P?0.01. Significant differences were observed between rapeseed cultivars. Effect of osmotic stress on length, volume, area and dry weight of roots, shoot dry weight and biological yield of different cultivars was not the same. The greatest amount of reduction in the studied traits under osmotic-stress conditions was observed in shoot dry weight and biological yield; root length was reduced the least. Based on cluster analysis, at all three levels of drought stress, canola cultivars were placed in three groups. The Licord cultivar, at all three conditions, was located in the group that its traits were higher than other groups. The Okapi, Quantum, Tallaye and Hyola308 cultivars showed lower tolerance to osmotic stress. The Licord cultivar had higher tolerance to osmotic stress as compared to other cultivars.

M. Nemati

2012-12-01

82

Disease in marine aquaculture  

Science.gov (United States)

It has become almost a truism that success in intensive production of animals must be based in part on development of methods for disease diagnosis and control. Excellent progress has been made in methods of diagnosis for major pathogens of cultivated fish, crustacean and molluscan species. In many instances these have proved to be facultative pathogens, able to exert severe effects in populations of animals under other stresses (marginal physical or chemical conditions; overcrowding). The concept of stress management as a critical prophylactic measure is not new, but its significance is being demonstrated repeatedly. The particular relationship of water quality and facultative pathogens such as Vibrio, Pseudomonas and Aeromonas species has been especially apparent. Virus diseases of marine vertebrates and invertebrates — little known two decades ago — are now recognized to be of significance to aquaculture. Virus infections of oysters, clams, shrimps and crabs have been described, and mortalities have been attributed to them. Several virus diseases of fish have also been recognized as potential or actual problems in culture. In some instances, the pathogens seem to be latent in natural populations, and may be provoked into patency by stresses of artificial environments. One of the most promising approaches to disease prophylaxis is through immunization. Fish respond well to various vaccination procedures, and new non-stressing methods have been developed. Vibriosis — probably the most severe disease of ocean-reared salmon — has been controlled to a great extent through use of a polyvalent bacterin, which can be modified as new pathogenic strains are isolated. Prophylactic immunization for other bacterial diseases of cultivated fish has been attempted, especially in Japan, with some success. There is also some evidence that the larger crustaceans may be immunologically responsive, and that at least short-term protection may be afforded to cultured populations. Some progress has been made in marine disease control through chemical treatment in intensive culture systems, principally through application and modification of methods developed for freshwater aquaculture. Major constraints to use of chemicals are restrictions due to public health concerns about food contamination, and the negative effects of some chemicals on biological filters and on algal food production. There is a continuing need, however, for development of specific treatments for acute disease episodes — such as the nitrofurans, developed in Japan, which are effective for some bacterial diseases. The history of aquaculture — freshwater as well as marine — has been characterized by transfers and introductions of species to waters beyond their present ranges. The process continues, and carries with it the possibility of transfers of pathogens to native species and to the recipient culture environments. International groups are attempting to define codes of practice to govern such mass movements, but examples of introductions of real or potential pathogens already exist. The most recent and the most dramatic is the world wide transfer of a virus pathogen of penaeid shrimps. Earlier examples include the introduction of a protozoan pathogen of salmonids to the western hemisphere, and the introduction of a parasitic copepod from the Far East to the west coast of North America and to France. The conclusion is inevitable — diseases are substantial deterrents to aquaculture production. Diagnostic and control procedures are and will be important components of emerging aquaculture technology.

Sindermann, C. J.

1984-03-01

83

RESEARCHES REGARDING THE TECHNOLOGICAL PERFORMANCES OF CARP REARING DURING WINTER PERIOD IN THE CONDITIONS OF A RECIRCULATING AQUACULTURE SYSTEM  

Directory of Open Access Journals (Sweden)

Full Text Available The techniques of carp culture are highly diversified, ranging from the extensive production in pond or open water with no fertilization or supplemental feeding to highly intensive systems in concrete tanks or cages. Among the different carp species, common carp is the best species reared in intensive monoculture, the others (Chinese and Indian carps being usually cultivated in polyculture (P. Kestemont, 1995. An experiment was conducted in inside recirculation system conditions to identify the technological performances on carp growth and survival at the Fishing and Aquaculture Department, Galati, during winter period (February, 2007 – March, 2007. The 1-year-old carp (Cyprinus carpio 4792g; 4594 g; 4561 g and 4525 g (total weight grew to 7384g; 7017g; 6924g and 7125 g in 44 days in aquarium 1, 2, 3 and 4, respectively. In all aquariums, the fish appeared healthy and no mortality was observed. Feed conversion efficiencies (FCE had similar values among all aquariums, the highest FCE being found in B4 aquarium with 1, 57 value. Water quality parameters were acceptable range for fish culture. Results show that the carp rearing during winter period in the inside recirculation system is a very good economic solution.

G. STEFAN

2013-12-01

84

Isotopes in aquaculture research  

International Nuclear Information System (INIS)

The applications of isotopes in aquaculture research include areas like aquatic production process, nutrient cycles and food chain dynamics, fish nutrition, fish physiology, genetics and immunology. The radioisotopes commonly used are beta emitters. The use of different radioisotopes in aquaculture research are presented. 2 tabs

85

Economic values of growth and feed efficiency for fish farming in recirculating aquaculture system with density and nitrogen output limitations: a case study with African catfish (Clarias gariepinus)  

OpenAIRE

In fish farming, economic values (EV) of breeding goal traits are lacking, even though they are key parameters when defining selection objectives. The aim of this study was to develop a bioeconomic model to estimate EV of 2 traits representing production performances in fish farming: the thermal growth coefficient (TGC) and the feed conversion ratio (FCR). This approach was applied to a farm producing African catfish (Clarias gariepinus) in a recirculating aquaculture system (RAS). In the RAS...

Besson, M.; Komen, H.; Aubin, J.; Boer, I. J. M.; Poelman, M.; Quillet, Edwige; Vancoillie, C.; Vandeputte, Marc; Arendonk, J. A. M.

2014-01-01

86

Impact of water boundary layer diffusion on the nitrification rate of submerged biofilter elements from a recirculating aquaculture system  

DEFF Research Database (Denmark)

Total ammonia nitrogen (TAN) removal by microbial nitrification is an essential process in recirculating aquaculture systems (RAS). In order to protect the aquatic environment and fish health, it is important to be able to predict the nitrification rates in RAS’s. The aim of this study was to determine the impact of hydraulic film diffusion on the nitrification rate in a submerged biofilter. Using an experimental batch reactor setup with recirculation, active nitrifying biofilter units from a RAS were exposed to a range of hydraulic flow velocities. Corresponding nitrification rates were measured following ammonium chloride, NH4Cl, spikes and the impact of hydraulic film diffusion was quantified. The nitrification performance of the tested biofilter could be significantly increased by increasing the hydraulic flow velocity in the filter. Area based first order nitrification rate constants ranged from 0.065 m d?1 to 0.192 m d?1 for flow velocities between 2.5 m h?1 and 40 m h?1 (18 °C). This study documents that hydraulic film diffusion may have a significant impact on the nitrification rate in fixed film biofilters with geometry and hydraulic flows corresponding to our experimental RAS biofilters. The results may thus have practical implications in relation to the design, operational strategy of RAS biofilters and how to optimize TAN removal in fixed film biofilter systems

Prehn, Jonas; Waul, Christopher Kevin

2012-01-01

87

Depletion of florfenicol amine in tilapia (Oreochromis sp.) maintained in a recirculating aquaculture system following Aquaflor®-medicated feed therapy  

Science.gov (United States)

Aquaflor® [50% w w?1 florfenicol (FFC)], is approved for use in freshwater-reared warmwater finfish which include tilapia Oreochromis spp. in the United States to control mortality from Streptococcus iniae. The depletion of florfenicol amine (FFA), the marker residue of FFC, was evaluated after feeding FFC-medicated feed to deliver a nominal 20 mg FFC kg?1 BW d?1 dose (1.33× the label use of 15 mg FFC kg?1 BW d?1) to Nile tilapia O. niloticus and hybrid tilapia O. niloticus × O. aureus held in a recirculating aquaculture system (RAS) at production-scale holding densities. Florfenicol amine concentrations were determined in fillets taken from 10 fish before dosing and from 20 fish at nine time points after dosing (from 1 to 240 h post-dosing). Water samples were assayed for FFC before, during and after the dosing period. Parameters monitored included daily feed consumption and biofilter function (levels of ammonia, nitrite and nitrate). Mean fillet FFA concentration decreased from 13.77 ?g g?1 at 1-h post dosing to 0.39 ?g g?1 at 240-h post dosing. Water FFC concentration decreased from a maximum of 1400 ng mL?1 at 1 day post-dosing to 847 ng mL?1 at 240 h post-dosing. There were no adverse effects noted on fish, feed consumption or biofilter function associated with FFC-medicated feed administration to tilapia.

Gaikowski, Mark P.; Whitsel, Melissa K.; Charles, Shawn; Schleis, Susan M.; Crouch, Louis S.; Endris, Richard G.

2013-01-01

88

Nitrogen and Phosphorus Removal in the Recirculating Aquaculture System with Water Treatment Tank containing Baked Clay Beads and Chinese Cabbage  

Directory of Open Access Journals (Sweden)

Full Text Available This research aims to describe the nitrogen and phosphorus removal in Recirculating Aquaculture System (RAS by crop plants biomass production. The 3 experiment systems consisted of 1 treatment (fish tank + baked clay beads + Chinese cabbage and 2 controls as control-1 (fish tank only and control-2 (fish tank + baked clay beads, were performed. With all experimental RAS, Nile tilapia (Oreochromis niloticus was cultured at 2 kg/m3 density. The baked clay beads (8-16 mm in diameter were filled as a layer of 10 cm in the water treatment tank of control-2. While in the treatment tank, Chinese cabbage (Brassica pekinensis was planted at 334 plants/m2 in baked clay beads layer. During 35 days of experiment, the average fish wet-weight in control-1, control-2 and treatment systems increased from 16.31±1.49, 15.18±1.28 and 11.31±1.49 g to 29.43±7.06, 28.65±3.12 and 27.20±6.56 g, respectively. It was found that the growth rate of 0.45±0.15 g-wet weight/day in a treatment tank was higher than in those 2 controls, which were rather similar at 0.37±0.16 and 0.38±0.05 g-wet weight/day, respectively. The fish survival rate of all experimental units was 100%. The average Chinese cabbage wet-weight in treatment system increased from 0.15±0.02 g to 1.00±0.38 g. For water quality, all parameters were within the acceptable range for aquaculture. The assimilation inorganic nitrogen in a treatment tank showed a slower rate and lower nitrite accumulation relative to those in control tanks. The nitrogen and phosphorus balance analysis illustrated that most of the nitrogen and phosphorus input in all systems was from feed (82-87% and 21-87% while at the final day of experiments, nitrogen and phosphorus in tilapia culture revealed at 15-19% and 4-13%. The accumulation of nitrogen and phosphorus in the water, up to 56% and 70%, was found in control-1 while water in the tank with baked clay beads had substantial lower nitrogen and phosphorus concentration. The most important part was unaccounted nitrogen and phosphorus as high as 60% and 17% in treatment and 53% and 10% in control-2 systems. Nitrogen and phosphorus incorporated in plant (treatment was only 1.31% and 0.11%, respectively. It can be implied from the results that the assimilation in plant was a minor process for nutrient removal in this RAS. On the other hand, the nitrification and denitrification occurred in the sediment layer of baked clay beads tank were the major treatment processes to maintain water quality in the recirculating system. Without baked clay bead, nitrogen waste was accumulated as nitrate in the water while in treatment tank with backed clay beads, nitrogen was significantly removed by denitrification process.

Aeknarin Thanakitpairin

2014-01-01

89

Optimization and evaluation of a bottom substrate denitrification tank for nitrate removal from a recirculating aquaculture system.  

Science.gov (United States)

A bottom substrate denitrification tank for a recirculating aquaculture system was developed. The laboratory scale denitrification tank was an 8 L tank (0.04 m2 tank surface area), packed to a depth of 5 cm with a bottom substrate for natural denitrifying bacteria. An aquarium pump was used for gentle water mixing in the tank; the dissolved oxygen in the water was maintained in aerobic conditions (e.g. > 2 mg/L) while anoxic conditions predominated only at the bottom substrate layer. The results showed that, among the four substrates tested (soil, sand, pumice stone and vermiculite), pumice was the most preferable material. Comparing carbon supplementation using methanol and molasses, methanol was chosen as the carbon source because it provided a higher denitrification rate than molasses. When methanol was applied at the optimal COD:N ratio of 5:1, a nitrate removal rate of 4591 +/- 133 mg-N/m2 tank bottom area/day was achieved. Finally, nitrate removal using an 80 L denitrification tank was evaluated with a 610 L recirculating tilapia culture system. Nitrate treatment was performed by batch transferring high nitrate water from the nitrification tank into the denitrification tank and mixing with methanol at a COD:N ratio of 5:1. The results from five batches of nitrate treatment revealed that nitrate was successfully removed from water without the accumulation of nitrite and ammonia. The average nitrate removal efficiency was 85.17% and the average denitrification rate of the denitrification tank was 6311 +/- 945 mg-N/m2 tank bottom area/day or 126 +/- 18 mg-N/L of pumice packing volume/day. PMID:24520693

Pungrasmi, Wiboonluk; Playchoom, Cholticha; Powtongsook, Sorawit

2013-08-01

90

Electronic flight instrument system  

OpenAIRE

This thesis describes basic concepts in research and development of a simple electronic flight instrument system, which displays piston engine data to the pilot. The main purpose is to build a functional prototype and acquire knowledge, which will enable us to further develop the system. The second chapter presents fundamentals of electronic flight instrument systems used in large commercial aircrafts. A detailed description of basic approaches to system implementation used by two of the b...

Hauptman, Luka

2009-01-01

91

Modelling studies of fish production in integrated agriculture-aquaculture systems.  

OpenAIRE

The general objective of this thesis is to formulate a general model for fish production in integrated ponds and ricefields as a means of obtaining a better understanding of these production systems. Integrated culture systems produce fish without large industrial energy inputs and have positive effects on the whole farm system. A main characteristic is their environmental variability, notably dissolved oxygen concentration and temperature. A systems approach using mathematical models is advo...

Dam, A. A.

1995-01-01

92

Single-sludge denitrification in recirculating aquaculture systems: Effects of pre-fermentation and pH  

DEFF Research Database (Denmark)

Single-sludge denitrification (DN) reactors in aquaculture utilize the solid fish waste produced in the system to reduce the nitrate load discharged. The solid waste is available for denitrifiers when present in soluble readily biodegradable form. A transformation accomplished by bacterial hydrolysis (and fermentation). The objective of this study was to quantify the effect of pre-fermentation of the solid fish waste on single-sludge DN-reactor efficiency. Pre-fermentation times tested were; 0 (no pre-fermentation), 1 d, 5 d, and 10 d. The efficiency was quantified as the potential DN-rates in laboratory assessments. Results showed that the highest DN-rate obtained was achieved by 1 d pre-fermentation. The volumetric DN-rate measured in decreasing order was; 23.4 ± 0.00 (1 d); 20.5 ± 0.35 (5 d); 17.0 ± 0.47 (10 d); 14.2 ± 0.24 (0 d) mg NO3-N (L?h)-1 It was suspected that the poor utilization of sCOD in 5 and 10 d pre-fermentation treatments were due to low start pH (below 7). Subsequently, the experiments were repeated in 0.1 M HEPES buffer pH=7.1, and showed a clear correlation between specific DN-rate and soluble COD content. Overall, the highest increase in potential specific DN-rate was achieved by applying pre-fermentation, e.g. from 0 d to 1 d the increase was 85 % and 106 % at unadjusted pH and pH 7.1, respectively. Additional 20 % increase was achieved at pH 7.1 by prolonging the pre-fermentation time to 5 d. At unadjusted pH conditions, the higher sCOD obtained by longer pre-fermentation was futile due to inhibitory effect of low pH

Suhr, Karin Isabel; Letelier Gordo, Carlos Octavio

2014-01-01

93

Electronic personal dosimetry system  

International Nuclear Information System (INIS)

NRPB has developed and commissioned a complete electronic personal dosemeter dosimetry system, intended for use as an approved dosimetry service. Tests of the dosemeter and system trials have been completed and the system submitted for approval by the Health and Safety Executive. Some of the important details of the system are described here. (author)

94

Stressing fish in Recirculating Aquaculture Systems (RAS): Does stress induced in one group of fish affect the feeding motivation of other fish sharing the same RAS?  

OpenAIRE

As a consequence of water re-use and high stocking densities, Recirculating Aquaculture Systems (RAS) may lead to an accumulation of substances released by the fish into the water, e.g. cortisol and alarm pheromones. This study investigated the effect of stressing fish on the feeding motivation of other fish not subjected to stress but sharing the same water of stressed fish. Two identical RAS were used (operated at 30 L kg feed?1 day?1) and contained grouped (stressed fish) and individua...

Martins, C. I.; Eding, E. H.; Verreth, J. A. J.

2011-01-01

95

Long-term effects of moderate elevation of oxidation–reduction potential on European seabass (Dicentrarchus labrax) in recirculating aquaculture systems  

OpenAIRE

The long term effects of moderate elevation ORP (oxidation–reduction potential) around 300–320 mV on the growth, hematological parameters and the ability of European seabass (Dicentrarchus labrax) to react against bacterial infection was studied in recirculating aquaculture systems (RASs). Two RASs, one with a moderate ozonation (RAS-O3) and a control (RAS-C) were used in this experiment. After 60 days, seabass reared in the RAS-O3 were more able to react against a Vibrio anguillarum infe...

Li, Xian; Przybyla, Cyrille; Triplet, Sebastien; Liu, Ying; Blancheton, Jean-paul

2014-01-01

96

Capacity building improve Malaysia's inspection and monitoring system for aquaculture and fishery products  

OpenAIRE

The project aimed to help build a credible inspection and monitoring system that can guarantee safe quality products of Ministry of Health (MoH) and Department of Fisheries (DoF) by upgrading the analytical capacity of the laboratory staff directly involved in the analysis and detection of forbidden substances. Two training courses were implemented in 2011 in the Bio Security Centre in Kuantan, Malaysia. The first training course on 'Marine lipophilic toxins using LC-MS/MS has been implemente...

Gevers, G. J. M.; Zoontjes, P. W.; Essers, M. L.; Klijnstra, M.; Gerssen, A.

2012-01-01

97

Enhancing the resilience of inland fisheries and aquaculture systems to climate change  

OpenAIRE

Some of the most important inland fisheries in the World are found in semi-arid regions. Production systems and livelihoods in arid and semi-arid areas are at risk from future climate variability and change; their fisheries are no exception. This paper reviews the importance of fisheries to livelihoods in ‘wetlands in drylands’, with a focus on case-studies in Africa. We examine the threats posed by climate change to the traditional ‘tri-economy’ of fishing, farming and livestock herd...

Allison, Edward H.; Andrew, Neil L.; Jamie Oliver

2007-01-01

98

Preliminary research on the anammox process and control of nitrogen compounds in a recirculating aquaculture system  

Directory of Open Access Journals (Sweden)

Full Text Available Using anammox process in biological filtration of technological water within recirculatingaquaculture system is an alternative to nitrification / denitrification process which can reduce productioncosts, especially energy by replacing aerobic biological processes that require high oxygen consumption,provided through the addition for optimal function of biofilter (conversion of N-NH4 and N-NO2. Aim ofthis paper is to highlight the first steps in the control of nitrogen compounds in recirculating aquaculturesystems using anammox process. Data shown are obtained after 78 researching days (research stillongoing, the results being encouraging, registering an ammonium removal efficiency of 77% in SC1 andof 32% in SC2. Nitrites registered an increase in SC1 and a decrease in SC2 and there are allprerequisites showing that in SC2 anammox activity is more advanced than in SC1. The average ofoxygen consumption rate was 0.73 mgL-1 in SC1 smaller than 0.99 mgL-1 from SC2, which reinforces theidea that there are anammox process in SC2.

Savin Cristian

2013-01-01

99

ELECTRONIC KANBAN SYSTEM SUPPORT  

OpenAIRE

More and more companies are making a transition from classical - to the stock manufacturing in to the lean system of pull production. Lately popular is automation of kanban cards or the so called electronic kanban or e-kanban. For the investment in such electronic kanban system, corporation TPV d.d. has decided. At the business unit in Brežice there has been an implementation of system E-klic or the so called project »call of the forklift« developed by the enterprise Oria d.o.o. The id...

Kostanjs?ek, Grega

2011-01-01

100

An Overview of Aquaculture in the Nordic Countries  

DEFF Research Database (Denmark)

The goal of this review was to describe in some detail the Nordic aquaculture industries in order to illuminate the similarities and differences. Information that was gathered for each country includes aquaculture history, aquaculture acts and regulations, production and production systems, environmental concerns, organic aquaculture and outlook for the future. The information will be useful for risk assessments, design of risk-based surveillance programs and for construction of comparative risk profiles for endemic and exotic diseases affecting aquaculture in the Nordic countries. Aquaculture in the Nordic countries has a long history; beginning in the 1850s when hatcheries for restocking of salmon and trout were established in Norway. Nowadays, Atlantic salmon is the dominant cultured species in Norway and the Faroe Islands, whereas rainbow trout dominate in Denmark, Finland, and Sweden. Arctic char and cod are most important in Iceland. Other important cultured species include eel and blue mussels. There is much diversity in Nordic aquaculture industries in terms of production, farmed species, and production systems. Although the vast majority of the Nordic aquaculture production is for human consumption, significant numbers of fish are grown for restocking of rivers, lakes, or other bodies of freshwater or seawater.

Paisley, Larry; Ariel, Ellen

2010-01-01

101

The influence of stocking density on growth performance and hematological profile of stellate sturgeon (A. stellatus, Pallas, 1771, reared in an industrial ,, flow-through’’ aquaculture system  

Directory of Open Access Journals (Sweden)

Full Text Available 800x600 The aim of this paper is to evaluate the influence of four different stocking densities, ranging from 18.7 to 28.6 kg m3, on growth performance and welfare of juvenile stellate sturgeons, reared in an industrial ,,flow-through’’ aquaculture system. At the end of 60 days experimental period, a survival rate of 98% and a stocking density that ranged from 32.5 to 39.8 kg m-3 were registered. The physiological state of biological material is characterized by the values ??of hematological indices, that are not significant from the statistical point of view (p> 0.05, both at the beginning and at the end of experimental period, as well as between experimental variants. To assess the biological material growth performance, feed conversion ratio (FCR, specific growth rate (SGR and profile index were calculated. Regarding the growth performance parameters, better value are encountered at B1 (18.7 kg m-3 and B3 (23.3 kg m-3, appreciable values ??at B2 (20.4 kg m-3 and low values at B4 (28.6 kg m-3. As conclusion, it can be assert that the initial stocking density of 28.6 kg m-3 is not optimal for rearing juvenile stellate sturgeons in an industrial ,,flow-through’’ aquaculture system. Normal 0 21 false false false RO X-NONE X-NONE MicrosoftInternetExplorer4

Desimira Maria Dicu Stroe

2013-10-01

102

Aquacultural Occupational Task Analysis.  

Science.gov (United States)

A study was conducted by the Office of the Chancellor for Community Colleges in Hawaii to assess the vocational skills required of workers in the aquaculture industry and to determine if these skills should be reflected in the community college curriculum. In addition to a review of relevant literature, the study involved field observations at 17…

Dung, Elaine; Wakui, Lawrence S.

103

Water and nutrient budgets of ponds in integrated agriculture-aquaculture systems in the Mekong Delta, Vietnam.  

OpenAIRE

A participatory on-farm study analysed water and nutrient budgets of six low and four high water-exchange ponds of integrated agriculture-aquaculture (IAA) farms in the Mekong delta. Water, nitrogen (N), organic carbon (OC) and phosphorus (P) flows through the ponds were monitored, and data on fish production and nutrient accumulation in sediments were collected during a fish culture cycle. Results showed that, on average, only 5-6% of total N, OC or P inputs introduced into ponds were recove...

Nhan, D. K.; Verdegem, M. C. J.; Milstein, A.; Verreth, J. A. J.

2008-01-01

104

Electronic instrumentation timing system  

International Nuclear Information System (INIS)

An electronic timing system that serves two important functions has been implemented on Nova. First, pulses can be generated at precise, controlled times relative to the Nova system trigger. These pulses simulate experimental signals without the need for laser shots. Transient recorder and streak camera triggers can now be timed independently of the laser system, greatly reducing setup time. The second function of the Nova electronic timing system is to accurately cross time signals on transient recorders. In past experiments, signals were cross-timed assuming common breakout times. Now, fiducial signals that are common to all transient recorders allow them to be independently cross-timed to an accuracy of better than 50 ps

105

Electron beam processing system  

International Nuclear Information System (INIS)

Electron beam Processing Systems (EPS) are used as useful and powerful tools in many industrial application fields such as the production of cross-linked wire, rubber tire, heat shrinkable film and tubing, curing, degradation of polymers, sterilization and environmental application. In this paper, the feature and application fields, the selection of machine ratings and safety measures of EPS will be described. (author)

106

Removal of nutrients in denitrification system using coconut coir fibre for the biological treatment of aquaculture wastewater.  

Science.gov (United States)

Ideal bacterial support medium for fixed film denitrification processes/bioreactors must be inexpensive, durable and possess large surface area with sufficient porosity. The present study has been focussed on removing nitrate nitrogen at two different nitrate nitrogen loading rates (60 (NLR I) and 120 (NLR II) mg l(-1)) from simulated aquaculture wastewater. Coconut coir fibre and a commercially available synthetic reticulated plastic media (Fujino Spirals) were used as packing medium in two independent upflow anaerobic packed bed column reactors. Removal of nitrate nitrogen was studied in correlation with other nutrients (COD, TKN, dissolved orthophosphate). Maximum removal of 97% at NLR-I and 99% at NLR - II of nitrate nitrogen was observed in with either media. Greater consistency in the case of COD removal of upto 81% was observed at NLR II where coconut coir was used as support medium compared to 72% COD removal by Fujino Spirals. The results observed indicate that the organic support medium is just as efficient in nitrate nitrogen removal as conventionally used synthetic support medium. The study is important as it specifically focuses on denitrification of aquaculture wastewater using cheaper organic support medium in anoxic bioreactors for the removal of nitrate nitrogen; which is seldom addressed as a significant problem. PMID:23033693

Manoj, Valsa Remony; Vasudevan, Namasivayam

2012-03-01

107

Electron-electron interactions in disordered systems  

CERN Document Server

``Electron-Electron Interactions in Disordered Systems'' deals with the interplay of disorder and the Coulomb interaction. Prominent experts give state-of-the-art reviews of the theoretical and experimental work in this field and make it clear that the interplay of the two effects is essential, especially in low-dimensional systems.

Efros, AL

1985-01-01

108

Molecular analysis of bacterial communities and detection of potential pathogens in a recirculating aquaculture system for Scophthalmus maximus and Solea senegalensis.  

Science.gov (United States)

The present study combined a DGGE and barcoded 16S rRNA pyrosequencing approach to assess bacterial composition in the water of a recirculating aquaculture system (RAS) with a shallow raceway system (SRS) for turbot (Scophthalmus maximus) and sole (Solea senegalensis). Barcoded pyrosequencing results were also used to determine the potential pathogen load in the RAS studied. Samples were collected from the water supply pipeline (Sup), fish production tanks (Pro), sedimentation filter (Sed), biofilter tank (Bio), and protein skimmer (Ozo; also used as an ozone reaction chamber) of twin RAS operating in parallel (one for each fish species). Our results revealed pronounced differences in bacterial community composition between turbot and sole RAS, suggesting that in the systems studied there is a strong species-specific effect on water bacterial communities. Proteobacteria was the most abundant phylum in the water supply and all RAS compartments. Other important taxonomic groups included the phylum Bacteriodetes. The saltwater supplied displayed a markedly lower richness and appeared to have very little influence on bacterial composition. The following potentially pathogenic species were detected: Photobacterium damselae in turbot (all compartments), Tenacibaculum discolor in turbot and sole (all compartments), Tenacibaculum soleae in turbot (all compartments) and sole (Pro, Sed and Bio), and Serratia marcescens in turbot (Sup, Sed, Bio and Ozo) and sole (only Sed) RAS. Despite the presence of these pathogens, no symptomatic fish were observed. Although we were able to identify potential pathogens, this approach should be employed with caution when monitoring aquaculture systems, as the required phylogenetic resolution for reliable identification of pathogens may not always be possible to achieve when employing 16S rRNA gene fragments. PMID:24278329

Martins, Patrícia; Cleary, Daniel F R; Pires, Ana C C; Rodrigues, Ana Maria; Quintino, Victor; Calado, Ricardo; Gomes, Newton C M

2013-01-01

109

Hydrogen peroxide decomposition kinetics in aquaculture water  

DEFF Research Database (Denmark)

Hydrogen peroxide (HP) is used in aquaculture systems where preventive or curative water treatments occasionally are required. Use of chemical agents can be challenging in recirculating aquaculture systems (RAS) due to extended water retention time and because the agents must not damage the fish reared or the nitrifying bacteria in the biofilters at concentrations required to eliminating pathogens. This calls for quantitative insight into the fate of the disinfectant residuals during water treatment. This paper presents a kinetic model that describes the HP decomposition in aquaculture water facilitated by microbial enzyme activity. The model describes how the hydrogen peroxide removal declines and eventually stops at relatively low chemical oxygen demand (COD) concentrations. It is hypothesized that this is due to an enzyme deficit because it is destructed due to the reactive radicals created during the HP decomposition. The model assumes that the enzyme decay is controlled by an inactivation stoichiometry related to the HP decomposition. In order to make the model easily applicable, it is furthermore assumed that the COD is a proxy of the active biomass concentration of the water and thereby the enzyme activity. This was, however, not measured. The model developed successfully described the removal of HP in aquaculture water from three types of RAS and model parameters are estimated. The model and the model parameters provide new information and are valuable tools to improve HP application in RAS by addressing disinfection demand and identify efficient and safe water treatment routines.

Arvin, Erik; Pedersen, Lars-Flemming

2015-01-01

110

Effect of Recirculating Aquaculture System (RAS on Growth Performance, Body Composition and Hematological Indicators of Allogynogenetic crucian Carp (Carassius auratus gibelio  

Directory of Open Access Journals (Sweden)

Full Text Available A Ditch Constructed Wetland unit (DCW was integrated into an outdoor RAS with four fishponds. This study evaluated the performance of the wetland unit in treating the recirculating wastewater and examined the effect of Recirculating Aquaculture System (RAS on growth performance, body composition and hematological indicators of the rearing fish. During a 165-days culture period, the DCW effectively reduced the influent concentrations of nutrients and can keep a good water quality at acceptable concentrations for growth of the fish. Growth performance, body composition and hematological indicators of Allogynogenetic crucian carp were closely related to water quality of their living environment. The RAS had improved the growth performance and quality of Allogynogenetic crucian carp.

Xiao-li Li

2013-03-01

111

Nutrients valorisation via duckweed-based wastewater treatment and aquaculture  

OpenAIRE

Development of a sustainable wastewater treatment scheme to recycle sewage nutrients and water in tilapia aquaculture was the main objective of this PhD research. Use of an Integrated UASB-duckweed ponds system for domestic wastewater treatment linked to tilapia aquaculture was investigated. The treatment system was efficiënt in organic matter removal during the entire year, while nitrogen, phosphorus and faecal coliform removal were negatively affected by the decline in tempera...

El-shafai, S. A. A. M.

2004-01-01

112

Leaf vegetables for use in integrated hydroponics and aquaculture systems: Effects of root flooding on growth, mineral composition and nutrient uptake  

DEFF Research Database (Denmark)

In recirculating aquaculture and hydroponics systems, the waste products from fish production are used to produce vegetables or other crops of economic value, and the water is recirculated to the fish tanks. We studied growth, productivity and nutrient uptake of four leaf vegetable species (Lactuca sativa, Ipomoea aquatica, Brassica rapa var. chinensis and Brassica rapa var. parachinensis) in a controlled growth experiment with three root flooding treatments (drained, half-flooded and flooded) to assess their preferred hydroponic growth requirements, biomass production and nutrient removal capacities. Growth of the two Brassica varieties was clearly best at drained root conditions, while L. sativa and I. aquatica grew best with half-flooded and flooded roots. I. aquatica took up 3 times more N, P and K per plant than L. sativa, and 4 to 6 times more than the two Brassica varieties. At a plant density of 30 plants/m2, I. aquatica produced 146 g DW/m2 aboveground biomass during a 30-day cultivation period containing 2.8, 0.9 and 6.8 g/m2 of N, P and K, respectively. L. sativa produced 115 g DW/m2 of aboveground DW during a 60-day cultivation period, containing 2.2, 0.6 and 4.6 g/m2 of N, P and K, respectively. The two Brassica varieties produced much less aerial biomass (50-54 g DW/m2 during a 60-day period). Both I. aquatica and L. sativa are promising species to be included in integrated hydroponic and aquaculture facilities, with I. aquatica showing the most promise because of its higher growth and nutrient uptake capacity. © 2010 Academic Journals

Trang, Ngo Thuy Diem; Schierup, Hans-Henrik

2010-01-01

113

Strongly Correlated Electronic Systems  

Science.gov (United States)

This dissertation presents several explorations into the field of many-body physics. In chapters 1-3 the fundamental nature of many-body interactions in quantum antiferromagnets is scrutinized. Chapter 1 surveys the modern theory of magnetic insulators, focusing on quantum antiferromagnets. Chapter 2 presents an improved method for computing expectation values of local operators in fully Gutzwiller -projected variational states. This embedded cluster method allows accurate extrapolation to the thermodynamic limit when the correlations are sufficiently short-range. The method is used to calculate static spin-spin correlations in a variety of one- and two-dimensional variational states for quantum antiferromagnets. Section 2.3.3 presents a study of the Heisenberg spin Hamiltonian on several lattices using Gutzwiller-projected variational wavefunctions with non-zero Neel order. The variational energies are comparable to more sophisticated calculations, suggesting that these variational wavefunctions are close to the true ground state wavefunction of the Heisenberg antiferromagnet. Chapter 3 discusses Gutzwiller-projected variational wavefunctions for charged, spinless holon excitations in chiral spin liquids. We find that these states describe anyons, with a statistical phase Phi_ {s} that is continuously adjustable between 0 and pi/2, depending on a variational parameter. The statistical flux attached to each holon is localized to within a lattice constant. Chapters 4 and 5 consider a superconducting and a magnetically ordered system, respectively, with the aim of understanding the many-body effects phenomenologically. Chapter 4 presents a self-contained overview of solid Buckminsterfullerene, C_{60}, with an emphasis on those aspects relevant to superconductivity. A BCS theory for superconductivity based on phonon-mediated electron pairing is also presented in some detail. In this model, the isotope effect is the most direct experimental indicator of the role played by phonons in the electron-electron pairing. The superconducting transition temperature of doped C_{60 } is unusually sensitive to partial substitution of ^{13}C for the naturally abundant isotope ^{12}C. Section 4.6 presents the theoretical temperature -dependent resistivity rho(T) resulting from a complete theory of the phonons in rm K_3C_{60} and rm Rb_3C_{60}. The electron-phonon couplings are derived from the theory highlighted in chapter 4. The theory accounts for the unusual non -linear temperature dependence in rho(T). . Finally, chapter 5 reviews several experiments on a variety of magnetic multi-layer and sandwich structures are reviewed. These systems have revealed an indirect exchange coupling between layers of ferromagnets separated by nonmagnetic spacer layers. This coupling oscillates from ferromagnetic to antiferromagnetic depending on the thickness of the spacer layers, with an anomalously long period. (Abstract shortened by UMI.).

Deaven, David Matthew

114

Evaluation on Biofilter in Recirculating Integrated Multi-Trophic Aquaculture  

OpenAIRE

Integrated multi-trophic aquaculture pays more attention as a bio-integrated food production system that serves as a model of sustainable aquaculture, minimizes waste discharge, increases diversity and yields multiple products. The objectives of this research were to analyze the efficiency of total ammonia nitrogen biofiltration and its effect on carrying capacity of fish rearing units. Pilot-scale bioreactor was designed with eight run-raceways (two meters of each) that assembled in serie...

Asfie Maidie; Sumoharjo, S.

2013-01-01

115

An ecosystem-based approach and management framework for the integrated evaluation of bivalve aquaculture impacts  

OpenAIRE

An ecosystem-based approach to bivalve aquaculture management is a strategy for the integration of aquaculture within the wider ecosystem, including human aspects, in such a way that it promotes sustainable development, equity, and resilience of ecosystems. Given the linkage between social and ecological systems, marine regulators require an ecosystem-based decision framework that structures and integrates the relationships between these systems and facilitates communication of aquaculture–...

Cranford, Peter J.; Kamermans, Pauline; Krause, Gesche; Mazurie?, Joseph; Buck, Bela H.; Dolmer, Per; Fraser, David; Nieuwenhove, Kris; O’beirn, Francis X.; Sanchez-mata, Adoracio?n; Thorarinsdo?ttir, Gudrun G.; Strand, Øivind

2012-01-01

116

Use of antimicrobial agents in aquaculture.  

Science.gov (United States)

The aquaculture industry has grown dramatically, and plays an important role in the world's food supply chain. Antimicrobial resistance in bacteria associated with food animals receives much attention, and drug use in aquaculture is also an important issue. There are many differences between aquatic and terrestrial management systems, such as the methods used for administration of drugs. Unique problems are related to the application of drugs in aquatic environments. Residual drugs in fish products can affect people who consume them, and antimicrobials released into aquatic environments can select for resistant bacteria. Moreover, these antimicrobial-resistant bacteria, or their resistance genes, can be transferred to humans. To decrease the risks associated with the use of antimicrobials, various regulations have been developed. In addition, it is necessary to prevent bacterial diseases in aquatic animals by vaccination, to improve culture systems, and to monitor the amount of antimicrobial drugs used and the prevalence of antimicrobial-resistant bacteria. PMID:22849275

Park, Y H; Hwang, S Y; Hong, M K; Kwon, K H

2012-04-01

117

BESIII online electronics calibration system  

International Nuclear Information System (INIS)

This paper introduce the components of BESIII DAQ System. It describe the relationship of internal online electrionics calibration's components, the mechanism of dataflow and message flow and the implementation of system functions. When BESIII is running, the system will be used to online calibrate electronics channels and provide the calibration params to adjust electronics data. (authors)

118

Aquaponics and its potential aquaculture wastewater treatment and human urine treatment  

OpenAIRE

The main objective of this thesis is to study the developing fields of aquaponics and its potential for aquaculture wastewater treatment and human urine treatment. Aquaponics is a food production system which combines fish farming (aquaculture) with soilless crop farming (hydroponics). In this thesis the concept of aquaponics and the underlying processes are explained. Research on aquaculture wastewater and human urine wastewater is reviewed and its potential application with aquaponic sys...

Sa?¡nchez, Henrique Junior Aiveca

2014-01-01

119

Efficiency of bioaugmentation in the removal of organic matter in aquaculture systems / Eficiência da bioadição na remoção de matéria orgânica em sistemas aquaculturais  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese Existem diversas tecnologias para tratamento de efluentes, o processo de bioadição consiste em uma vertente da biorremediação e tem sido empregado na melhoria da qualidade dos efluentes através do tratamento da água de produção. Esta tecnologia consiste basicamente na adição de microrganismos com a [...] capacidade de degradar ou remover compostos poluentes, especialmente matéria orgânica e nutrientes. Este estudo objetivou avaliar os efeitos da suplementação de composto bioativo sobre alguns parâmetros de matéria orgânica e de desempenho de juvenis de tilápias em um sistema intensivo de produção aquacultural. Foi empregada a combinação de dois consórcios bacterianos em delineamento inteiramente aleatorizado, em um esquema fatorial com dois fatores. As diferenças estatísticas entre os tratamentos foram analisadas por meio da análise de variância (ANOVA) e do teste de Tukey ao nível de 5%. Verificou-se neste estudo, que a bioadição heterotrófica foi capaz de reduzir em 23% a demanda bioquímica de oxigênio (DBO); em 83,7%, o carbono orgânico dissolvido (COD); e em 43%, a biomassa fitoplanctônica. Por outro lado, não se observou nenhum prejuízo com relação aos parâmetros físico-químicos de qualidade de água bem como ao desempenho de crescimento para juvenis de tilápias avaliados neste estudo. Abstract in english Several techniques are currently used to treat effluents. Bioaugmentation is a new bioremediation strategy and has been employed to improve effluent quality by treating the water during the production process. This technology consists basically of the addition of microorganisms able to degrade or re [...] move polluting compounds, especially organic matter and nutrients. The objective of this study was to assess the effects of bioaugmentation on some parameters of organic matter and on the performance of juvenile tilapias in an intensive aquaculture production system. The combination of two bacterial consortiums in a complete randomized design was employed in a factorial analysis with two factors. Statistical differences between treatments were analyzed by the analysis of variance (ANOVA) and Tukey test at the 5% level. One of the treatments, heterotrophic bacterial supplementation, was able to reduce biochemical oxygen demand (BOD) by 23%, dissolved organic carbon (DOC) by 83.7% and phytoplanktonic biomass by 43%. On the other hand, no damage was done to either the physical-chemical indicators of water quality or to the growth performance of juvenile tilapias assessed in this study.

RB, Lopes; RA., Olinda; BAI, Souza; JEP, Cyrino; CTS, Dias; JF, Queiroz; LHS, Tavares.

2011-05-01

120

Economic values of growth and feed efficiency for fish farming in recirculating aquaculture system with density and nitrogen output limitations: a case study with African catfish (Clarias gariepinus).  

Science.gov (United States)

In fish farming, economic values (EV) of breeding goal traits are lacking, even though they are key parameters when defining selection objectives. The aim of this study was to develop a bioeconomic model to estimate EV of 2 traits representing production performances in fish farming: the thermal growth coefficient (TGC) and the feed conversion ratio (FCR). This approach was applied to a farm producing African catfish (Clarias gariepinus) in a recirculating aquaculture system (RAS). In the RAS, 2 factors could limit production level: the nitrogen treatment capacity of the biofilter or the fish density in rearing tanks at harvest. Profit calculation includes revenue from fish sales, cost of juveniles, cost of feed, cost of waste water treatment, and fixed costs. In the reference scenario, profit was modeled to zero. EV were calculated as the difference in profit per kilogram of fish between the current population mean for both traits (µt) and the next generation of selective breeding (µt+?t) for either TGC or FCR. EV of TGC and FCR were calculated for three generations of hypothetical selection on either TGC or FCR (respectively 6.8% and 7.6% improvement per generation). The results show that changes in TGC and FCR can affect both the number of fish that can be stocked (number of batches per year and number of fish per batch) and the factor limiting production. The EV of TGC and FCR vary and depend on the limiting factors. When dissolved NH3-N is the limiting factor for both µt and µt+?t, increasing TGC decreases the number of fish that can be stocked but increases the number of batches that can be grown. As a result, profit remains constant and EVTGC is zero. Increasing FCR, however, increases the number of fish stocked and the ratio of fish produced per kilogram of feed consumed ("economic efficiency"). The EVFCR is 0.14 €/kg of fish, and profit per kilogram of fish increases by about 10%. When density is the limiting factor for both µt and µt+?t, the number of fish stocked per batch is fixed; therefore, extra profit is obtained by increasing either TGC, which increases the annual number of batches, or by decreasing FCR, which decreases annual feed consumption. EVTGC is 0.03 €/kg of fish and EVFCR is 0.05-0.06 €/kg of fish. These results emphasize the importance of calculating economic values in the right context to develop efficient future breeding programs in aquaculture. PMID:25414104

Besson, M; Komen, H; Aubin, J; de Boer, I J M; Poelman, M; Quillet, E; Vancoillie, C; Vandeputte, M; van Arendonk, J A M

2014-12-01

121

Reliability of electronic systems  

International Nuclear Information System (INIS)

Reliability techniques have been developed subsequently as a need of the diverse engineering disciplines, nevertheless they are not few those that think they have been work a lot on reliability before the same word was used in the current context. Military, space and nuclear industries were the first ones that have been involved in this topic, however not only in these environments it is that it has been carried out this small great revolution in benefit of the increase of the reliability figures of the products of those industries, but rather it has extended to the whole industry. The fact of the massive production, characteristic of the current industries, drove four decades ago, to the fall of the reliability of its products, on one hand, because the massively itself and, for other, to the recently discovered and even not stabilized industrial techniques. Industry should be changed according to those two new requirements, creating products of medium complexity and assuring an enough reliability appropriated to production costs and controls. Reliability began to be integral part of the manufactured product. Facing this philosophy, the book describes reliability techniques applied to electronics systems and provides a coherent and rigorous framework for these diverse activities providing a unifying scientific basis for the entire subject. It consists of eight chapters plus a lot of statistical tables and an extensive annotated bibliography. Chapters embrace the follod bibliography. Chapters embrace the following topics: 1- Introduction to Reliability; 2- Basic Mathematical Concepts; 3- Catastrophic Failure Models; 4-Parametric Failure Models; 5- Systems Reliability; 6- Reliability in Design and Project; 7- Reliability Tests; 8- Software Reliability. This book is in Spanish language and has a potentially diverse audience as a text book from academic to industrial courses. (author)

122

Application of chemical coagulation aids for the removal of suspended solids (TSS) and phosphorus from the microscreen effluent discharge of an intensive recirculating aquaculture system  

Science.gov (United States)

An evaluation of two commonly used coagulation-flocculation aids (alum and ferric chloride) was conducted to determine optimum conditions for treating the backwash effluent from microscreen filters in an intensive recirculating aquaculture system. Tests were carried out to evaluate the dosages and conditions (mixing and flocculation stirring speeds, durations, and settling times) required to achieve optimum waste capture. The orthophosphate removal efficiency for alum and ferric chloride were greater than 90% at a dosage of 60 mg/L. Optimum turbidity removal was achieved with a 60-mg/L dosage for both alum and ferric chloride. Both alum and ferric chloride demonstrated excellent removal of suspended solids from initial total suspended solid values of approximately 320 mg/L to approximately 10 mg/L at a dosage of 60 mg/L. Flocculation and mixing speed and duration played only a minor role in the removal efficiencies for both orthophosphates and suspended solids. Both coagulation-flocculation aids also exhibited excellent settling characteristics, with the majority of the floc quickly settling out in the first 5 min.

Ebeling, J.M.; Ogden, S.R.; Sibrell, P.L.; Rishel, K.L.

2004-01-01

123

Results regarding growth performance of Nile tilapia (Oreochromis niloticus, Linnaeus, 1758 fed with an additive feed, vitamin C, in a recirculating aquaculture system.  

Directory of Open Access Journals (Sweden)

Full Text Available The aim of this study was to determine the vitamin C status on growth performance, survival rate and biochimical parameters from tissue of Nile tilapia (Oreochromis niloticus, Linnaeus, 1758 with average weight of 93±1,0 g were fed with different dietary vitamin C rations and reared in a recirculating aquaculture system (RAS. Growth performance , survival rate and biochimical parameters from tissue of Nile tilapia were measured in groups fed diets supplemented with 100, 750, 2000 mg.kg-1L-ascorbic acid (AA and almost ascorbate free diet (Total AA> 5 mg.kg-1 as a control. They were stocked in 12 rearing units at 28 oC water temperature for 30 days. Diet of 33 % protein was offered as feed, 3 times daily. Growth measurements of tilapia were recorded on beginning and at the end of the experiment. Results showed that growth performance for Nile tilapia had not significantly (p>0.05 differences between the control and the tretments . Survival rate was the same for al the treatments. The feed conversio ratio (FCR was not significant (p>0.05 between the control and the treatments. Resuls showed that the feed impoved with AA had no significant differences between treatments and control regarding the  optimum growth performance and survival rate at Nile tilapia.  

Catalina Ciortan Mirea

2013-10-01

124

Potential use of power plant reject heat in commercial aquaculture  

International Nuclear Information System (INIS)

Current research and commercial activities in aquaculture operations have been reviewed. An aquaculture system using mostly herbivorous species in pond culture is proposed as a means of using waste heat to produce reasonably priced protein. The system uses waste water streams, such as secondary sewage effluent, animal wastes, or some industrial waste streams as a primary nutrient source to grow algae, which is fed to fish and clams. Crayfish feed on the clam wastes thereby providing a clean effluent from the aquaculture system. Alternate fish associations are presented and it appears that a carp or tilapia association is desirable. An aquaculture system capable of rejecting all the waste heat from a 1000-MW(e) power station in winter can accommodate about half the summer heat rejection load. The aquaculture facility would require approximately 133 ha and would produce 4.1 x 105 kg/year of fish, 1.5 x 106 kg/year of clam meat, and 1.5 x 104 kg/year of live crayfish. The estimated annual pretax profit from this operation is one million dollars. Several possible problem areas have been identified. However, technical solutions appear to be readily available to solve these problems. The proposed system shows considerable economic promise. Small scale experiments have demonstrated the technical feasibility of various components of the system. It therefore appears that a pilot scale experimental facility should be operated

125

Potential use of power plant reject heat in commercial aquaculture  

Energy Technology Data Exchange (ETDEWEB)

Current research and commercial activities in aquaculture operations have been reviewed. An aquaculture system using mostly herbivorous species in pond culture is proposed as a means of using waste heat to produce reasonably priced protein. The system uses waste water streams, such as secondary sewage effluent, animal wastes, or some industrial waste streams as a primary nutrient source to grow algae, which is fed to fish and clams. Crayfish feed on the clam wastes thereby providing a clean effluent from the aquaculture system. Alternate fish associations are presented and it appears that a carp or tilapia association is desirable. An aquaculture system capable of rejecting all the waste heat from a 1000-MW(e) power station in winter can accommodate about half the summer heat rejection load. The aquaculture facility would require approximately 133 ha and would produce 4.1 x 10/sup 5/ kg/year of fish, 1.5 x 10/sup 6/ kg/year of clam meat, and 1.5 x 10/sup 4/ kg/year of live crayfish. The estimated annual pretax profit from this operation is one million dollars. Several possible problem areas have been identified. However, technical solutions appear to be readily available to solve these problems. The proposed system shows considerable economic promise. Small scale experiments have demonstrated the technical feasibility of various components of the system. It therefore appears that a pilot scale experimental facility should be operated.

Olszewski, M.

1977-01-01

126

Electrodynamics of correlated electron systems  

OpenAIRE

Physical and chemical systems can be characterized by their natural frequency and energy scales. It is hardly an exaggeration that most of what we know about such systems, from the acoustics of a violin to the energy levels of atoms, comes from their response to perturbations at these natural frequencies. It is of course the same situation in `correlated' electron materials. We can learn about the novel effects of strong electron-electron interactions and the properties of c...

Armitage, N. P.

2009-01-01

127

Ecosystem-based approach to aquaculture management  

Directory of Open Access Journals (Sweden)

Full Text Available Ecosystems have real thresholds and limits which, when exceeded, can affect major system restructuring. Once thresholds and limits have been exceeded, changes can be irreversible. Diversity is important to ecosystem functioning. The ecosystem approach is a strategy for the integrated management of land, water, and living resources that promotes conservation and sustainable use in an equitable way. The application of the ecosystem approach will help to reach a balance of the three main objectives: conservation, sustainable use, and a fair and equitable sharing of the benefits and use of the natural resources. Aquaculture development needs to be within the carrying capacity of the water resource so that it is sustainable and does not greatly impact the environment. The determination of the carrying capacity needs to be science-based. The planning of development in ecosystems has been done for freshwater ecosystems within the PAMB (Protected Area Management Board framework, but in many cases this does not give the correct significance to the impact of aquaculture on the water resources in the ecosystem. It also needs to be extended to river basins and estuaries, brackishwater areas, and inland bays, and seas. The planning and management of aquaculture needs to be undertaken at the local government unit (LGU level in a coordinated manner by all the LGUs that have a part of the water resource. The co-management of aquaculture, in terms of monitoring of the environment, monitoring of production, and monitoring of licenses, needs to be funded out of license fees and non-compliance fines collected by the LGUs. A number of these management activities need to be undertaken jointly (monitoring the environment and others separately but in a coordinated manner (e.g., checking licenses and checking compliance.

Patrick White

2008-12-01

128

The ALS Gun Electronics system  

International Nuclear Information System (INIS)

The ALS Gun Electronics system has been designed to accommodate gun with a custom made socket and high speed electronics circuit which is capable of producing single and multiple electron bunches with time jitters measured at better than 50 PS. The system generates the gated RF signal at ground level before sending it up to the 120 KV-biased gun deck via a fiber optic cable. The current pulse width as a function of grid bias, using an Eimac 8847A planar triode simulating an electron gun, was measured to show the relationship between the two parameters

129

The ALS gun electronics system  

International Nuclear Information System (INIS)

The ALS Gun Electronics system has been designed to accommodate the gun with a custom made socket and a high speed electronics circuit which is capable of producing single and multiple electron bunches with time jitters measured at better than 50 PS. The system generates the gated RF signal at ground level before sending it up to the 120 KV-biased gun deck via a fiber optic cable. The current pulse width as a function of grid bias, using an Eimac 8847A planar triode simulating an electron gun, was measured to show the relationship between the two parameters

130

Realization of dynamical electronic systems  

OpenAIRE

This article gives an overview of a methodology for building dynamical electronic systems. As an example a part of a system for epileptic seizure prediction is used, which monitors EEG signals and continuously calculates the largest short-term Lyapunov exponents. In dynamical electronic systems, the cost of exploitation, for instance energy consumption, may vary substantially with the values of input signals. In addition, the functions describing the variations are not known at the time the s...

Hammari Elena; Catthoor Francky; Iasemidis Leonidas; Gunnar Kjeldsberg Per; Huisken Jos; Tsakalis Konstantinos

2014-01-01

131

Electronical Health Record's Systems. Interoperability  

CERN Document Server

Understanding the importance that the electronic medical health records system has, with its various structural types and grades, has led to the elaboration of a series of standards and quality control methods, meant to control its functioning. In time, the electronic health records system has evolved along with the medical data change of structure. Romania has not yet managed to fully clarify this concept, various definitions still being encountered, such as "Patient's electronic chart", "Electronic health file". A slow change from functional interoperability (OSI level 6) to semantic interoperability (level 7) is being aimed at the moment. This current article will try to present the main electronic files models, from a functional interoperability system's possibility to be created perspective.

Apostol, Simona Angela; Vernic, Corina

2009-01-01

132

ISO/TC 234, Fisheries and Aquaculture  

OpenAIRE

The largest standard developing organization, ISO, works these days at International Standards for Fisheries and Aquaculture. They created a technical committee divided in six work groups that will have to establish cage technology, aquaculture environmental management, aquaculture technology, food safety for aquaculture farms, traceability of fishery products and environmental monitoring on the seabed’s impact from marine finfish farms. These standards will promote the sustainable developm...

Costea, Ramona I.

2009-01-01

133

Application of Machine Learning Techniques in Aquaculture  

OpenAIRE

In this paper we present applications of different machine learning algorithms in aquaculture. Machine learning algorithms learn models from historical data. In aquaculture historical data are obtained from farm practices, yields, and environmental data sources. Associations between these different variables can be obtained by applying machine learning algorithms to historical data. In this paper we present applications of different machine learning algorithms in aquaculture...

Akhlaqur Rahman; Sumaira Tasnim

2014-01-01

134

Electronical Health Record's Systems. Interoperability  

OpenAIRE

Understanding the importance that the electronic medical health records system has, with its various structural types and grades, has led to the elaboration of a series of standards and quality control methods, meant to control its functioning. In time, the electronic health records system has evolved along with the medical data change of structure. Romania has not yet managed to fully clarify this concept, various definitions still being encountered, such as "Patient's elec...

Simona Angela Apostol; Catu Cosmin; Corina Vernic

2008-01-01

135

Applications of probiotic in aquaculture  

Directory of Open Access Journals (Sweden)

Full Text Available Ecological impacts including emergence of a large variety of pathogens and bacterial resistance is caused in increase of productivity in aquaculture. This negatively effects are seen as a results of made applications in production cycles (such as randomly use kemoteropatik. Using probi¬otic in aquaculture is a new approach to reduce these negatively effects. In this study is submi¬ted, definition of the concept probiotic, effect mechanisms of probiotics, colonization to host, selection of probiotics, use probiotic in fish, crustacean, the mollusk and the live feed.

Seval Bahad?r Koca

2011-10-01

136

FTU bolometer electronic system upgrade  

International Nuclear Information System (INIS)

Highlights: ? Design and realization of a new bolometer electronic system. ? Many improvements over the actual commercial system. ? Architecture based on digital electronic hardware with minimal analog front end. ? Auto off-set correction, real time visualization features and small system size. ? Test results for the electronic system. -- Abstract: The FTU (Frascati Tokamak Upgrade) requires a bolometer diagnostic in order to measure the total plasma radiation. The current diagnostic architecture is based on a full analog multichannel AC bolometer system, which uses a carrier frequency amplifier with a synchronous demodulation. Taking into account the technological upgrades in the field of electronics, it was decided to realize an upgrade for the bolometric electronic system by using a hybrid analog/digital implementation. The new system developed at the ENEA Frascati laboratories has many improvements, and mainly a massive system volume reduction, a good measurement linearity and a simplified use. The new hardware system consists of two subsystems: the Bolometer Digital Control and the Bolometer Analog System. The Bolometer Digital Control can control 16 bolometer bridges through the Bolometer Analog System. The Bolometer Digital Control, based on the FPGA architecture, is connected via Ethernet with a PC; therefore, it can receive commands settings from the PC and send the stream of bolometric measurements in real time to the PC. In order to solve the cross-talk between the bridges and the cables, each of the four bridges in the bolometer head receives a different synthesized excitation frequency. Since the system is fully controlled by a PC GUI (Graphic User Interface), it is very user friendly. Moreover, some useful features have been developed, such as: auto off-set correction, bridge amplitude regulation, software gain setting, real time visualization, frequency excitation selection and noise spectrum analyzer embedded function. In this paper, the hardware and software system architectures are described and some tests of the developed system are presented, with a related statistical analysis

137

ELECTRONIC PAYMENT SYSTEMS AND THE USE OF ELECTRONIC MONEY  

OpenAIRE

In this diploma thesis, we presented the concept of electronic money and electronic payment systems. We presented the advantages and disadvantages of electronic money and the reasons why it has been introduced. We presented and compared various examples of electronic money, technology that provides security and the risks that exist in the web and mobile use of electronic money. We have shown how electronic payment systems are classified and presented the SEPA project, which establishes these ...

Komel, Domen

2012-01-01

138

DNA vaccines for aquacultured fish  

DEFF Research Database (Denmark)

Deoxyribonucleic acid (DNA) vaccination is based on the administration of the gene encoding the vaccine antigen, rather than the antigen itself. Subsequent expression of the antigen by cells in the vaccinated hosts triggers the host immune system. Among the many experimental DNA vaccines tested in various animal species as well as in humans, the vaccines against rhabdovirus diseases in fish have given some of the most promising results. A single intramuscular (IM) injection of microgram amounts of DNA induces rapid and long-lasting protection in farmed salmonids against economically important viruses such as infectious haematopoietic necrosis virus (IHNV) and viral haemorrhagic septicaemia virus (VHSV). DNA vaccines against other types of fish pathogens, however, have so far had limited success. The most efficient delivery route at present is IM injection, and suitable delivery strategies for mass vaccination of small fish have yet to be developed. In terms of safety, no adverse effects in the vaccinated fishhave been observed to date. As DNA vaccination is a relatively new technology, various theoretical and long-term safety issues related to the environment and the consumer remain to be fully addressed, although inherently the risks should not be any greater than with the commercial fish vaccines that are currently used. Present classification systems lack clarity in distinguishing DNA-vaccinated animals from genetically modified organisms (GMOs), which could raise issues in terms of licensing and public acceptance of the technology. The potential benefits of DNA vaccines for farmed fish include improved animal welfare, reduced environmental impacts of aquaculture activities, increased food quality and quantity, and more sustainable production. Testing under commercial production conditions has recently been initiated in Canada and Denmark.

Lorenzen, Niels; LaPatra, S.E.

2005-01-01

139

ELECTRONIC SYSTEM FOR AQUARIUM CONTROL  

OpenAIRE

The main subject of this thesis is to develop an electronic system for aquarium control. We are going to implement both hardware and software solutions, which will provide remote control and measurements of basic quantities in aquarium. We also described all necessary knowledge, technology and tools used to implement the system.

S?korc, Jure

2011-01-01

140

Component reliability for electronic systems  

CERN Document Server

The main reason for the premature breakdown of today's electronic products (computers, cars, tools, appliances, etc.) is the failure of the components used to build these products. Today professionals are looking for effective ways to minimize the degradation of electronic components to help ensure longer-lasting, more technically sound products and systems. This practical book offers engineers specific guidance on how to design more reliable components and build more reliable electronic systems. Professionals learn how to optimize a virtual component prototype, accurately monitor product reliability during the entire production process, and add the burn-in and selection procedures that are the most appropriate for the intended applications. Moreover, the book helps system designers ensure that all components are correctly applied, margins are adequate, wear-out failure modes are prevented during the expected duration of life, and system interfaces cannot lead to failure.

Bajenescu, Titu-Marius I

2010-01-01

141

Realization of dynamical electronic systems  

Directory of Open Access Journals (Sweden)

Full Text Available This article gives an overview of a methodology for building dynamical electronic systems. As an example a part of a system for epileptic seizure prediction is used, which monitors EEG signals and continuously calculates the largest short-term Lyapunov exponents. In dynamical electronic systems, the cost of exploitation, for instance energy consumption, may vary substantially with the values of input signals. In addition, the functions describing the variations are not known at the time the system is designed. As a result, the architecture of the system must accommodate for the worst case exploitation costs, which rapidly exceed the available resources (for instance battery life when accumulated over time. The presented system scenario methodology solves these challenges by identifying at design time groups of possible exploitation costs, called system scenarios, and implementing a mechanism to detect system scenarios at run time and re-configure the system to cost-efficiently accommodate them. During reconfiguration, the optimized system architecture settings for the active system scenario are selected and the total exploitation cost is reduced. When the dynamic behavior is due to input data variables with a large number of possible values, current techniques for bottom-up scenario identification and detection becomes too complex. A new top-down technique, based on polygonal regions, is presented in this paper. The results for the example system indicate that with 10 system scenarios the average energy consumption of the system can be reduced by 28% and brought within 5% of the theoretically best solution.

Hammari Elena

2014-04-01

142

Produção do híbrido "cachadia" em diferentes densidades de estocagem em sistema de recirculação de água / Production of cachadia hybrid at different densities in a recirculating aquaculture system  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Avaliou-se o efeito da densidade de estocagem na produção de "cachadia" (Pseudoplatystoma fasciatum x Leiarius marmoratus) em sistema de recirculação de água. Nas duas primeiras fases, com duração de 27 e 40 dias e usando animais com média de peso inicial de 31 e 57g, respectivamente, foram testados [...] 20, 40, 60 e 80 peixes/m³. Na terceira e quarta fase, usando peixes com média de peso de 169 e 399g durante 41 e 99 dias, respectivamente, foram testados 10, 20, 30 e 40 peixes/m³. A taxa de sobrevivência foi acima de 92%, sem diferenças significativas entre tratamentos. Verificou-se redução no ganho de peso diário com redução com o incremento da densidade na segunda e na quarta fase experimental. A biomassa final apresentou relação direta com a densidade em todas as fases. Taxas de conversão alimentar entre 0,8 e 1,3:1 foram registradas. O "cachadia" atingiu 1,1kg em 207 dias de cultivo, mostrando-se promissor para a piscicultura intensiva. Abstract in english The aim of this study was to investigate the effect of different stocking densities on cachadia production (Pseudoplatystoma fasciatum x Leiarius marmoratus) in recirculating aquaculture system. In the two first phases for 27 and 40 days using fish with average weight of 31 and 57g, respectively, de [...] nsities 20, 40, 60, and 80 fish/m³ were tested. In the third and fourth trial, using fish with an average weight of 169 and 399g during 41 and 99 days, respectively, densities 10, 20, 30, and 40 fish/m³ were tested. Survival rate was higher than 92%, without stocking density differences between the treatments. Daily weight gain showed reduction with the increase of the density in the second and fourth trial. However, final biomass presented direct relationship with increase density in all trials. Feed conversion rates ranged 0.8 from 1.3:1 were registered. Cachadia hybrid reached 1.1kg in approximately seven months of rearing indicating promise for intensive production.

P.M.C, Faria; R.K, Luz; S.A, Prado; E.M, Turra; T.B.F, Jorge; A.M.Q, Lana; E.A, Teixeira.

1208-12-01

143

PREFACE: Strongly correlated electron systems Strongly correlated electron systems  

Science.gov (United States)

This special section is dedicated to the Strongly Correlated Electron Systems Conference (SCES) 2011, which was held from 29 August-3 September 2011, in Cambridge, UK. SCES'2011 is dedicated to 100 years of superconductivity and covers a range of topics in the area of strongly correlated systems. The correlated electronic and magnetic materials featured include f-electron based heavy fermion intermetallics and d-electron based transition metal compounds. The selected papers derived from invited presentations seek to deepen our understanding of the rich physical phenomena that arise from correlation effects. The focus is on quantum phase transitions, non-Fermi liquid phenomena, quantum magnetism, unconventional superconductivity and metal-insulator transitions. Both experimental and theoretical work is presented. Based on fundamental advances in the understanding of electronic materials, much of 20th century materials physics was driven by miniaturisation and integration in the electronics industry to the current generation of nanometre scale devices. The achievements of this industry have brought unprecedented advances to society and well-being, and no doubt there is much further to go—note that this progress is founded on investments and studies in the fundamentals of condensed matter physics from more than 50 years ago. Nevertheless, the defining challenges for the 21st century will lie in the discovery in science, and deployment through engineering, of technologies that can deliver the scale needed to have an impact on the sustainability agenda. Thus the big developments in nanotechnology may lie not in the pursuit of yet smaller transistors, but in the design of new structures that can revolutionise the performance of solar cells, batteries, fuel cells, light-weight structural materials, refrigeration, water purification, etc. The science presented in the papers of this special section also highlights the underlying interest in energy-dense materials, which make use of 'small' electrons packed to the highest possible density. These are by definition 'strongly correlated'. For example: good photovoltaics must be efficient optical absorbers, which means that photons will generate tightly bound electron-hole pairs (excitons) that must then be ionised at a heterointerface and transported to contacts; efficient solid state refrigeration depends on substantial entropy changes in a unit cell, with large local electrical or magnetic moments; efficient lighting is in a real sense the inverse of photovoltaics; the limit of an efficient battery is a supercapacitor employing mixed valent ions; fuel cells and solar to fuel conversion require us to understand electrochemistry on the scale of a single atom; and we already know that the only prospect for effective high temperature superconductivity involves strongly correlated materials. Even novel IT technologies are now seen to have value not just for novel function but also for efficiency. While strongly correlated electron systems continue to excite researchers and the public alike due to the fundamental science issues involved, it seems increasingly likely that support for the science will be leveraged by its impact on energy and sustainability. Strongly correlated electron systems contents Strongly correlated electron systemsSiddharth S Saxena and P B Littlewood Magnetism, f-electron localization and superconductivity in 122-type heavy-fermion metalsF Steglich, J Arndt, O Stockert, S Friedemann, M Brando, C Klingner, C Krellner, C Geibel, S Wirth, S Kirchner and Q Si High energy pseudogap and its evolution with doping in Fe-based superconductors as revealed by optical spectroscopyN L Wang, W Z Hu, Z G Chen, R H Yuan, G Li, G F Chen and T Xiang Structural investigations on YbRh2Si2: from the atomic to the macroscopic length scaleS Wirth, S Ernst, R Cardoso-Gil, H Borrmann, S Seiro, C Krellner, C Geibel, S Kirchner, U Burkhardt, Y Grin and F Steglich Confinement of chiral magnetic modulations in the precursor region of FeGeH Wilhelm, M Baenitz, M Schmidt, C Naylor, R Lortz, U

Saxena, Siddharth S.; Littlewood, P. B.

2012-07-01

144

Vehicle electronic systems: 1999. Proceedings  

Energy Technology Data Exchange (ETDEWEB)

These conference proceedings present papers on new developments in technologies and tools for the automotive electronics industry. Topics covered include: electric-powered vehicles; energy storage systems; new batteries for future vehicles; propulsion motors for electric hybrid vehicles. Telematics - driver information, looked at future products and services such as digital radio, multimedia and intelligent transportation systems. Telematics - vehicle control, included collision mitigation and headway monitoring sensors. A diagnostic system to analyse any problems on power drive and control systems, and analysis of exhaust gases after treatment to reduce NO{sub x} emissions in diesel engines, is also included. One paper is abstracted.

Anon

1999-07-01

145

Power electronic systems Walsh analysis with Matlab  

CERN Document Server

A Totally Different Outlook on Power Electronic System AnalysisPower Electronic Systems: Walsh Analysis with MATLAB® builds a case for Walsh analysis as a powerful tool in the study of power electronic systems. It considers the application of Walsh functions in analyzing power electronic systems, and the advantages offered by Walsh domain analysis of power electronic systems. Solves Power Electronic Systems in an Unconventional WayThis book successfully integrates power electronics as well as systems and control. Incorporating a complete orthonormal function set very much unlike the sine-cosin

Deb, Anish

2014-01-01

146

Enfoque sistémico para el diseño de sistemas energéticos acuícolas resilientes: discusión aplicada al caso de una empresa de cultivos / Systematic approach to design resilient energy systems to aquaculture: discussion applied in a private hatchery  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: Spanish Abstract in spanish El presente trabajo documenta experiencias en la aplicación del enfoque sistémico a un proceso productivo en el campo de la acuicultura. Particularmente, se analiza el modelo de producción de energía, orientado a la resiliencia y baja emisión de carbono, implementado en un hatchery privado. Lo anter [...] ior pretende contribuir con una herramienta que apoye a disminuir los impactos ambientales y consecuentemente sociales y económicos, a escala local, regional y global, asociados a la producción y gestión energética, incrementando la eficiencia en el uso de recursos, la competitividad y resiliencia de la actividad acuícola. Adicionalmente, se presenta un enfoque de modelo de negocios sistémico, que podría ser adaptado a cualquier proceso productivo, extendiendo el campo de aplicación a diversos rubros. Abstract in english This paper documents the experiences of applying the systemic approach to a production process in the field of aquaculture. Particularly, we analyze the energy production model, oriented to resilience and low carbon emission, implemented in a private hatchery. This intends to contribute a tool to su [...] pport lessen environmental, and consequently social and economic impacts at local, regional and global production and associated energy management, increasing efficiency in the use of resources, competitiveness and resilience of aquaculture. Additionally, we present an approach for systemic business model that could be adapted to any production process, extending the scope to diverse areas.

Marcelo, Concha; Claudia, Cerda; Mariana, Zappi.

2012-09-01

147

EDITORIAL: Strongly correlated electron systems Strongly correlated electron systems  

Science.gov (United States)

Strongly correlated electrons is an exciting and diverse field in condensed matter physics. This special issue aims to capture some of that excitement and recent developments in the field. Given that this issue was inspired by the 2010 International Conference on Strongly Correlated Electron Systems (SCES 2010), we briefly give some history in order to place this issue in context. The 2010 International Conference on Strongly Correlated Electron Systems was held in Santa Fe, New Mexico, a reunion of sorts from the 1989 International Conference on the Physics of Highly Correlated Electron Systems that also convened in Santa Fe. SCES 2010—co-chaired by John Sarrao and Joe Thompson—followed the tradition of earlier conferences, in this century, hosted by Buzios (2008), Houston (2007), Vienna (2005), Karlsruhe (2004), Krakow (2002) and Ann Arbor (2001). Every three years since 1997, SCES has joined the International Conference on Magnetism (ICM), held in Recife (2000), Rome (2003), Kyoto (2006) and Karlsruhe (2009). Like its predecessors, SCES 2010 topics included strongly correlated f- and d-electron systems, heavy-fermion behaviors, quantum-phase transitions, non-Fermi liquid phenomena, unconventional superconductivity, and emergent states that arise from electronic correlations. Recent developments from studies of quantum magnetism and cold atoms complemented the traditional subjects and were included in SCES 2010. 2010 celebrated the 400th anniversary of Santa Fe as well as the birth of astronomy. So what's the connection to SCES? The Dutch invention of the first practical telescope and its use by Galileo in 1610 and subsequent years overturned dogma that the sun revolved about the earth. This revolutionary, and at the time heretical, conclusion required innovative combinations of new instrumentation, observation and mathematics. These same combinations are just as important 400 years later and are the foundation of scientific discoveries that were discussed during SCES 2010. As we learned, past dogmas about strongly correlated materials and phenomena must be re-examined with an open and inquisitive mind. Invited speakers and respected leaders in the field were invited to contribute to this special issue and we have insisted that they present new data, ideas, or perspectives, as opposed to simply an overview of their past work. As with the conference, this special issue touches upon recent developments of strongly correlated electron systems in d-electron materials, such as Sr3Ru2O7, graphene, and the new Fe-based superconductors, but it is dominated by topics in f-electron compounds. Contributions reflect the growing appreciation for the influence of disorder and frustration, the need for organizing principles, as well as detailed investigations on particular materials of interest and, of course, new materials. As this special issue could not possibly capture the full breadth and depth that the conference had to offer, it is being published simultaneously with an issue of Journal of Physics: Conference Series containing 157 manuscripts in which all poster presenters at SCES 2010 were invited to contribute. Since this special issue grew out of the 2010 SCES conference, we take this opportunity to give thanks. This conference would not have been possible without the hard work of the SCES 2010 Program Committee, International and National Advisory Committees, Local Committee, and conference organizers, the New Mexico Consortium. We thank them as well as those organizations that generously provided financial support: ICAM-I2CAM, Quantum Design, Lakeshore, the National High Magnetic Field Laboratory and the Department of Energy National Laboratories at Argonne, Berkeley, Brookhaven, Los Alamos and Oak Ridge. Of course, we especially thank the participants for bringing new ideas and new results, without which SCES 2010 would not have been possible. Strongly correlated electron systems contents Spin-orbit coupling and k-dependent Zeeman splitting in strontium ruthenate Emil J Rozbicki, James F Annett, Jean-René Souquet an

Ronning, Filip; Batista, Cristian

2011-03-01

148

Genomic approaches in aquaculture and fisheries  

DEFF Research Database (Denmark)

Despite the enormous input into the worldwide development of fish and shellfish farming in the recent decades, in part as an attempt to minimize the impact of fishing on already overexploited natural populations, the application of genomics to aquaculture and fisheries remains poorly developed. Improving state-of-the-art genomics research in various aquaculture systems, as well as its industrial applications, remains one of the major challenges in this area and should be the focus of well developed strategies to be implemented in the next generation of projects. This chapter will first provide an overview of the genomic tools and resources available, then discuss the application of genomic approaches to the improvement of fish and shellfish farming (e.g. breeding, reproduction, growth, nutrition and product quality), including the evaluation of stock diversity and the use of selection procedures. The chapter will also discuss the use of genomic approaches to study and monitor natural fish and shellfish populations and to understand interactions within their ecosystems.

Cancela, M. Leonor; Bargelloni, Luca

2010-01-01

149

Status of Irish Aquaculture 2007  

OpenAIRE

This is the fifth annual report to review the status of Irish aquaculture (see Parsons et al., 2004, Parsons et al., 2005, Browne et al., 2006, and Browne et al., 2007). As with previous editions it has been produced in collaboration with the three main State agencies that provide support services in the areas of research and development to the industry – Bord Iascaigh Mhara (BIM), the Marine Institute (MI) and Údarás na Gaeltachta. The objectives of this and previous reports are: (1) To ...

Institute, Marine; Mhara, Bord Iascaigh; Gaeltachta, U?dara?s Na

2008-01-01

150

Use of Probiotics in Aquaculture  

Science.gov (United States)

The growth of aquaculture as an industry has accelerated over the past decades; this has resulted in environmental damages and low productivity of various crops. The need for increased disease resistance, growth of aquatic organisms, and feed efficiency has brought about the use of probiotics in aquaculture practices. The first application of probiotics occurred in 1986, to test their ability to increase growth of hydrobionts (organisms that live in water). Later, probiotics were used to improve water quality and control of bacterial infections. Nowadays, there is documented evidence that probiotics can improve the digestibility of nutrients, increase tolerance to stress, and encourage reproduction. Currently, there are commercial probiotic products prepared from various bacterial species such as Bacillus sp., Lactobacillus sp., Enterococcus sp., Carnobacterium sp., and the yeast Saccharomyces cerevisiae among others, and their use is regulated by careful management recommendations. The present paper shows the current knowledge of the use of probiotics in aquaculture, its antecedents, and safety measures to be carried out and discusses the prospects for study in this field. PMID:23762761

Martínez Cruz, Patricia; Ibáñez, Ana L.; Monroy Hermosillo, Oscar A.; Ramírez Saad, Hugo C.

2012-01-01

151

Field reliability of electronic systems  

International Nuclear Information System (INIS)

This report investigates, through several examples from the field, the reliability of electronic units in a broader sense. That is, it treats not just random parts failure, but also inadequate reliability design and (externally and internally) induced failures. The report is not meant to be merely an indication of the state of the art for the reliability prediction methods we know, but also as a contribution to the investigation of man-machine interplay in the operation and repair of electronic equipment. The report firmly links electronics reliability to safety and risk analyses approaches with a broader, system oriented view of reliability prediction and with postfailure stress analysis. It is intended to reveal, in a qualitative manner, the existence of symptom and cause patterns. It provides a background for further investigations to identify the detailed mechanisms of the faults and the remedical actions and precautions for achieving cost effective reliability. (author)

152

REVIEW OF AQUACULTURE GENETIC RESEARCHES IN THAILAND  

OpenAIRE

Aquaculture business has been well established in Thailand for more than 40 years. The most recent data indicated a total production of 260 380 tons. Sixty-five percent of the total production came from coastal aquaculture, mainly tiger prawn (Penaeus monodon) culture. Other important species for coastal aquaculture are banana prawn (P. merguensis), cockle (Anadara granosa), green mussel (Perna viridis), oyster (Crassostrea belcheri, Saccostrea commercialis), sea bass (Lates calcarifer) and g...

UTHAIRAT NA-NAKORN

1992-01-01

153

7 CFR 1437.303 - Aquaculture, including ornamental fish.  

Science.gov (United States)

...false Aquaculture, including ornamental fish. 1437.303 Section 1437.303 Agriculture...303 Aquaculture, including ornamental fish. (a) Aquaculture is a value loss...consumption as determined by CCC. (2) Fish raised as feed for other fish that...

2010-01-01

154

Use of an Electronic Tongue System to Detect Methylisoborneol in Distilled Water  

Science.gov (United States)

An electronic tongue (ET) system consisting of conducting polymer sensors was employed to detect 2-methylisoborneol (MIB) in distilled water. MIB is a tainting compound and known to cause undesirable tastes and odours in water and aquaculture farming. Samples of distilled water with different concentrations of MIB were analysed in order to evaluate the capabilities of the ET system. Principal component analysis (PCA) showed that for higher concentrations of MIB (50 and 100 ng?L-1) the ET could separate the tainted samples into distinct clusters. Clusters of untainted and tainted samples with lower concentrations (bellow 10 ng?L-1) overlapped and resulted in a single cluster. Nevertheless, close grouping between repeated tests indicated that the ET system response is reproducible.

Braga, Guilherme S.; Paterno, Leonardo G.; Fonseca, Fernando J.

2009-05-01

155

Computer Aided Control and Monitoring of Aquaculture Plants  

OpenAIRE

A computer system for control and monitoring of aquaculture plants has been developed by the Norwegian company NODEC. The system is based on a local area network which interfaces a computer system to the primary instruments located at various sites in the plant. Special software modules have been developed to handle different tasks such as data gathering, automatic control, alarming, logging, trend analysis and reporting. Special effort has been made to develop a user-friendly high level man-...

Erik Hansen

1987-01-01

156

Sediment quality and production data of black tiger shrimp (Penaeus monodon culture under Code of Conduct for Responsible Shrimp Aquaculture (CoC system and ordinary system of intensive shrimp farms  

Directory of Open Access Journals (Sweden)

Full Text Available The study of sediment qualities and production data of black tiger shrimp (Penaeus monodon culture was carried out in 5 ponds practised following CoC guideline (CoC: “Code of Conduct for Responsible Shrimp Aquaculture” and in 10 ponds practised following common guideline of ordinary intensive farm (OIF. All the ponds were located in Songkhla and Nakhon Si Thammarat provinces and the study period was during March 2003-January 2004. It was found that sediment qualities (organic matter as %ignition loss, TN andTOC and pH of OIF system were significantly higher (p<0.05 than those of the CoC system only during the period 30-60 days of culture which was the most critical period of shrimp culture. This evidence suggests a significant effect on deterioration of the pond bottom causing an unsuitable ecological condition for shrimp living on the pond bottom. Our result on production data showed that the production and variable cost of production were about 794 kg/rai, and 114.6 baht/kg in the CoC system, while those of the OIF were 377 kg/ rai and 185.6 baht/kg, respectively.

Klaysri, S.

2005-02-01

157

Antimicrobial use and resistance in aquaculture: findings of a globally administered survey of aquaculture-allied professionals.  

Science.gov (United States)

There is limited published information regarding antimicrobial use (AMU) and antimicrobial resistance (AMR) in aquaculture. Our objective was to determine the opinions of aquaculture-allied professionals around the world on the frequency of AMU and AMR in common aquatic species. The study questionnaire included five sections: respondent demographics, extent of AMU in aquaculture, frequency of observations of AMR in aquaculture, AMR monitoring and surveillance and antimicrobial susceptibility testing in various jurisdictions. It was administered in English and Spanish to 604 professionals in 25 countries and with varying expertise in aquaculture. The response rate was 33% (199/604). Over half of the participants had >10 years of experience in aquaculture: 70% (140/199) were involved in fish health/clinical work and their primary experience was with salmon, tilapia, trout, shrimp (including prawn) and/or catfish. Tetracycline use was reported by 28%, 46%, 18%, 37% and 9% of respondents working with catfish, salmon, tilapia, trout and shrimp, respectively. Resistance to tetracycline in one or more species of bacteria was reported as 'frequent-to-almost always' for the same aquaculture species by 39%, 28%, 17%, 52% and 36% of respondents, respectively. 'Frequent-to-almost always' use of quinolone was reported by 70% (32/46) and 67% (8/12) of respondents from the United States and Canada, respectively, where quinolone products are not approved for aquaculture, and extra-label fluoroquinolone use is either prohibited (United States) or discouraged (Canada). Similar frequencies of quinolone use were also reported by the majority of respondents from Europe [70% (7/10)] and Asia [90% (9/10)] where labelled indications exist. This baseline information can be used to prioritize research or surveillance for AMU and AMR in aquaculture. PMID:23072270

Tuševljak, N; Dutil, L; Raji?, A; Uhland, F C; McClure, C; St-Hilaire, S; Reid-Smith, R J; McEwen, S A

2013-09-01

158

Feed Additives for Aquaculture and Aquarium Culture  

OpenAIRE

The presente invention refers of feed additives for aquaculture and aquarium culture. These additives comprise the amino acid, 1-methyl-L-tryptophane, or its isomers with the objective of improving the attractiveness of feeds used in aquaculture and aquaria for fish, as well as other aquatic organisms, under culture conditions. Therefore, this invention has applications in the agriculture-food industry.

Barata, Eduardo N.; Velez, Ze?lia

2011-01-01

159

Fishing the Future: The Need For Aquaculture  

Science.gov (United States)

The issue-focused, reviewed, student article illustrates how aquaculture, or seafood farming, may be the best solution to dwindling food supplies. Its development is urgently needed because: overpopulation has exceeded Earth's capacity to feed us, fisheries have been exploited to a dangerous level, and aquaculture is a reliable, safe, and inexpensive source of food.

Ronald Hsu (West Shore Jr./Sr. High School in Melbourne, FL;)

2001-07-01

160

Sustainable Treatment of Aquaculture Effluents—What Can We Learn from the Past for the Future?  

Directory of Open Access Journals (Sweden)

Full Text Available Many aquaculture systems generate high amounts of wastewater containing compounds such as suspended solids, total nitrogen and total phosphorus. Today, aquaculture is imperative because fish demand is increasing. However, the load of waste is directly proportional to the fish production. Therefore, it is necessary to develop more intensive fish culture with efficient systems for wastewater treatment. A number of physical, chemical and biological methods used in conventional wastewater treatment have been applied in aquaculture systems. Constructed wetlands technology is becoming more and more important in recirculating aquaculture systems (RAS because wetlands have proven to be well-established and a cost-effective method for treating wastewater. This review gives an overview about possibilities to avoid the pollution of water resources; it focuses initially on the use of systems combining aquaculture and plants with a historical review of aquaculture and the treatment of its effluents. It discusses the present state, taking into account the load of pollutants in wastewater such as nitrates and phosphates, and finishes with recommendations to prevent or at least reduce the pollution of water resources in the future.

Ariel E. Turcios

2014-02-01

161

Decomposition of high protein aquaculture feed under variable oxic conditions  

OpenAIRE

The microbial decomposition of nitrogen-rich organic matter in aquaculture ponds is affected by the oxic-anoxic conditions gradient at the soil¿water interface as well as by resuspension practices. To investigate these interactions, the decomposition of a 49% protein fish feed was analyzed in 10 marine lab-scale systems with different exposures to aerobic and anaerobic conditions. The degree of coupling between oxic and anoxic conditions in the system had a strong effect on product accumulat...

Torres Beristain, B.; Verdegem, M. C. J.; Kerepeczki, E.; Verreth, J. A. J.

2006-01-01

162

DIFFERENT PLANT DERIVED BY-PRODUCTS USE IN FRESHWATER AQUACULTURE IN INDIA  

Directory of Open Access Journals (Sweden)

Full Text Available As aquacultural practices increase in magnitude and hasten the flow ofmaterials and energy through the systems, compared to natural conditions, it stands toreason that many organic wastes can, save both monetary and caloric inputs into themodern aquaculture if these wastes are processed suitably and used as manure inincreasing productivity of the pond or as feed stuff to replace high cost ingredients in theformulation of diet for fish.

KAUSIK MONDAL

2013-05-01

163

How to measure the economic impacts of changes in growth, feed efficiency and survival in aquaculture  

OpenAIRE

In this article we introduce a variety of bio-economic models that can be used to calculate the economic benefits associated with improved productivity in aquaculture. In the aquaculture industry, three important biological productivity factors are growth, survival and feed efficiency. The profitability of improving productivity factors, especially growth, is highly dependent upon the cost factor structure, production system, its constraints and other factors within the supply chain. Therefor...

Kankainen, M.; Setala, J.; Berrill, I. K.; Ruohonen, K.; Noble, C.; Schneider, O.

2012-01-01

164

Digital simulation of power electronic systems  

International Nuclear Information System (INIS)

The following paper contains the final report on the NETSIM-Project. The purpose of this project is to develop a special digital simulation system, which could serve as a base for routine application of simulation in planning and development of power electronic systems. The project is realized in two steps. First a basic network analysis system is established. With this system the basic models and methods in treating power electronic networks could be probed. The resulting system is then integrated into a general digital simulation system for continous systems (CSSL-System). This integrated simulation system allows for convenient modeling and simulation of power electronic systems. (orig.)

165

REVIEW OF AQUACULTURE GENETIC RESEARCHES IN THAILAND  

Directory of Open Access Journals (Sweden)

Full Text Available Aquaculture business has been well established in Thailand for more than 40 years. The most recent data indicated a total production of 260 380 tons. Sixty-five percent of the total production came from coastal aquaculture, mainly tiger prawn (Penaeus monodon culture. Other important species for coastal aquaculture are banana prawn (P. merguensis, cockle (Anadara granosa, green mussel (Perna viridis, oyster (Crassostrea belcheri, Saccostrea commercialis, sea bass (Lates calcarifer and grouper (Epinephelus tauvina. Freshwater aquaculture, although produced only 35% of the annual production, provides major protein source for people in rural areas. Important freshwater species are Nile tilapia (Oreochromis niloticus, tawes (Puntius gonionotus, sepat Siam (Trichogasterpectoralis, walking catfish (Glorias spp., stripped catfish (Pangasius sutchi and giant freshwater prawn (Macrobrachium rosenbergii. Optimum aquacultural practises, namely stocking density, nutrition requirement and water quality have been obtained in most cultured species. But genetic approach has not been considered, thus resulting in deterioration in economic traits which might be due to excessive inbreeding (reviewed by Uraiwan 1989 and/or negative selection (Wongsangchan 1985. The history of researches on genetics in aquaculture in Thailand started in 1982 when the aquaculture genetic programme in form of a network has been established at the National Inland Fisheries Institute, Department of Fisheries. This programme was supported by the International Development Research Centre (IDRC, Canada in cooperation with Dalhousie University, Canada (Uraiwan 1989. In the same year a genetic improvement programme aiming at improving economic characters of some economic fish species has been conducted at the Department of Aquaculture, Kasetsart University. Paralelly a course in Fish Genetics has been offered. Since then different approaches of genetics have been applied with final objectives on improving aquaculture production of the country. Researches being conducted are reviewed according to the following fish species.

UTHAIRAT NA-NAKORN

1992-01-01

166

PROBLEMS OF BIOFOULING ON FISH–CAGE NETS IN AQUACULTURE  

OpenAIRE

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 ne...

Merica Sliškovi?; Gorana Jeli?

2002-01-01

167

Scenarios for Resilient Shrimp Aquaculture in Tropical Coastal Areas  

OpenAIRE

We contend there are currently two competing scenarios for the sustainable development of shrimp aquaculture in coastal areas of Southeast Asia. First, a landscape approach, where farming techniques for small-scale producers are integrated into intertidal areas in a way that the ecological functions of mangroves are maintained and shrimp farming diseases are controlled. Second, a closed system approach, where problems of disease and effluent are eliminated in closed recirculation ponds behind...

Boer, Willem F.; Roel Bosma; Han van Dijk; Leontine Visser; Zwieten, Paul A. M.; Bush, Simon R.; Marc Verdegem

2010-01-01

168

Knowledge and Skill Guidelines for Aquaculture Technicians  

Science.gov (United States)

The Marine Advanced Technology Education Center (MATE) has provided this overview of knowledge and skill guidelines for aquaculture technicians. The report begins with detailing the background of the creation of these guidelines, which occurred at the third annual Rhode Island Aquaculture Conference in Warwick, Rhode Island. Competency areas for aquaculture technicians outlined in the report are laboratory skills, math skills, knowledge of basic chemistry, field experience, knowledge of basic biology, mechanical skills, communication skills, analytical skills, internship experience, time management skills, computer skills, basic business skills and staying up-to-date.

169

Biogeochemical ecology of aquaculture ponds  

International Nuclear Information System (INIS)

Two methods to determine rates of organic matter production and consumption were applied in shrimp aquaculture ponds. Several questions were posed: can net rates of organic matter production and consumption be determined accurately through application of dissolved inorganic carbon (DIC) mass balance in a pond with high advective through-put? Are organically loaded aquaculture ponds autotrophic? How do rates of organic production vary temporally? Are there diurnal changes in respiration rates? Four marine ponds in Hawaii have been evaluated for a 53 day period through the use of geochemical mass balances. All fluxes of DIC into and out of the ponds were considered. DIC was calculated from hourly pH measurements and weekly alkalinity measurements. Average uptake of DIC from the pond water, equivalent to net community production, revealed net autotrophy in all cases. Hourly and longer period variations in organic matter production rates were examined. The daily cycle dominated the variation in rates of net community production. Maximal rates of net community production were maintained for four to six hours starting in mid-morning. Respiration rates decreased rapidly during the night in two of the ponds and remained essentially constant in the others. A similar pattern of decreasing respiration at night was seen in freshwater shrimp ponds which were studied with incubations. A new method involving isotope dilution of 14C-labeled DIC was used to measure respiratC-labeled DIC was used to measure respiration rates in light and dark bottles. This method is an inexpensive and convenient procedure which should also be useful in other environments. The incubations demonstrated that plankton respiration rates peak at or soon after solar noon and vary over the course of the day by about a factor of two

170

Carbon dioxide stripping in aquaculture. part 1: terminology and reporting  

Science.gov (United States)

The removal of carbon dioxide gas in aquacultural systems is much more complex than for oxygen or nitrogen gas because of liquid reactions of carbon dioxide and their kinetics. Almost all published carbon dioxide removal information for aquaculture is based on the apparent removal value after the CO2(aq) + HOH ? H2CO3 reaction has reached equilibrium. The true carbon dioxide removal is larger than the apparent value, especially for high alkalinities and seawater. For low alkalinity freshwaters (<2000 ?eq/kg), the difference between the true and apparent removal is small and can be ignored for many applications. Analytical and reporting standards are recommended to improve our understanding of carbon dioxide removal.

Colt, John; Watten, Barnaby; Pfeiffer, Tim

2012-01-01

171

Liposarcoma in clownfish, Amphiprion ocellaris Cuvier, produced in indoor aquaculture.  

Science.gov (United States)

Clownfish, Amphiprion ocellaris Cuvier, produced and grown in an experimental indoor aquaculture facility, presented with lipomatous tumours. A total of 14 affected fish were examined. Based on the total number of fish at the aquaculture facility at the time of outbreak of this pathology, the scope of the incident is estimated to be 1 of 300 fish. The tumours were characterized by the presence of mature adipocytes of variable sizes, lipoblasts and by an invasive behaviour, which affected internal organs, muscle, central nervous system and, in one case, an eye. Detailed macroscopic and histopathological features are presented. The suggested diagnosis is that of a well-differentiated liposarcoma, a diagnosis so far never applied to fish. The limited outbreak of the neoplasm lasted a few months in 2011 and did not recur. Possible factors leading to this phenomenon, notably the metastasis, are discussed. PMID:24917512

Sharon, G; Benharroch, D; Kachko, L; Reis-Hevlin, N; Zilberg, D

2014-06-11

172

Characterization and significance of indicator bacteria in commercial aquaculture production facilities  

Energy Technology Data Exchange (ETDEWEB)

Catfish production is the single largest segment of the domestic aquaculture industry. Waste discharges from aquaculture operations are regulated at both the federal and state level. The federal government regulates surface water discharges from aquaculture facilities using regulations promulgated under the Clean Water Act. These regulations designate concentrated aquatic animal production facilities as point sources of pollution, thus subjecting them to National Pollution Discharge Elimination Systems (NPDES) permit requirements. Previous studies of aquaculture effluents have primarily characterized the organic, chemical, and physical components of discharged wastewater and have only characterized to a limited extent the microbial component of discharged wastewater. This study was initiated to examine the levels of four wastewater indicator bacteria groups and to examine to the genus level the members of one of these groups in wastewater, or potential wastewater, from aquaculture facilities over the course of the growout season of several different species of fish. This study also examined the relationships between these bacterial levels and other water quality parameters and operational variables and enumerated and characterized Aeromonas hydrophila complex bacteria, members of which are potential water-borne pathogens. The effectiveness of waste stabilization ponds in the treatment of aquaculture wastewaters was also evaluated.

Fiederlein, R.J.; Davis, E.M.; Mathewson, J.J. [Univ. of Texas School of Public Health, Houston, TX (United States)

1996-11-01

173

X2000 power system electronics development  

Science.gov (United States)

The X2000 Power System Electronics (PSE) is a Jet Propulsion Laboratory (JPL) task to develop a new generation of power system building blocks for potential use on future deep space missions. The effort includes the development of electronic components and modules that can be used as building blocks in the design of generic spacecraft power systems.

Carr, Greg; Deligiannis, Frank; Franco, Lauro; Jones, Loren; Lam, Barbara; Nelson, Ron; Pantaleon, Jose; Ruiz, Ian; Treichler, John; Wester, Gene; Sauers, Jim; Giampoli, Paul; Haskell, Russ; Mulvey, Jim; Repp, John

2005-01-01

174

Risks of Using Antifouling Biocides in Aquaculture  

OpenAIRE

Biocides are chemical substances that can deter or kill the microorganisms responsible for biofouling. The rapid expansion of the aquaculture industry is having a significant impact on the marine ecosystems. As the industry expands, it requires the use of more drugs, disinfectants and antifoulant compounds (biocides) to eliminate the microorganisms in the aquaculture facilities. The use of biocides in the aquatic environment, however, has proved to be harmful as it has toxic effects on the ma...

José Meseguer; Maria Angeles Esteban; Francisco Antonio Guardiola; Alberto Cuesta

2012-01-01

175

Understanding electronic systems in semiconductor quantum dots  

International Nuclear Information System (INIS)

Systems of confined electrons are found everywhere in nature in the form of atoms where the orbiting electrons are confined by the Coulomb attraction of the nucleus. Advancement of nanotechnology has, however, provided us with an alternative way to confine electrons by using artificial confining potentials. A typical structure of this nature is the quantum dot, a nanoscale system which consists of few confined electrons. There are many types of quantum dots ranging from self-assembled to miniaturized semiconductor quantum dots. In this work we are interested in electrostatically confined semiconductor quantum dot systems where the electrostatic confining potential that traps the electrons is generated by external electrodes, doping, strain or other factors. A large number of semiconductor quantum dots of this type are fabricated by applying lithographically patterned gate electrodes or by etching on two-dimensional electron gases in semiconductor heterostructures. Because of this, the whole structure can be treated as a confined two-dimensional electron system. Quantum confinement profoundly affects the way in which electrons interact with each other, and external parameters such as a magnetic field. Since a magnetic field affects both the orbital and the spin motion of the electrons, the interplay between quantum confinement, electron–electron correlation effects and the magnetic field gives rise to very interesting physical phenomena. Thus, confined systems of electrons in a semiconductor quantum dot represent a unique opportunity to study fundamental quantum theories in a controllable atomic-like setup. In this work, we describe some common theoretical models which are used to study confined systems of electrons in a two-dimensional semiconductor quantum dot. The main emphasis of the work is to draw attention to important physical phenomena that arise in confined two-dimensional electron systems under various quantum regimes. (comment)

176

Coincidence imaging system with electron optics  

Energy Technology Data Exchange (ETDEWEB)

As a part of multiple-detector system for coincidence instrumental neutron activation analysis (CINAA) a new method which includes a devoted electron optic unit has been built. In order to achieve higher sensitivity, enhanced contrast and higher spatial resolution the new coincidence imaging arrangement newly incorporates to electron optic unit, source, the gamma detector and the Timepix electron detector. The electron optic unit can be configured for different electron energies. The description of the assembled apparatus, calibration and performance for different electron energies are presented.

Kroupa, Martin, E-mail: martin.kroupa@utef.cvut.cz [Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horska 3a/22, CZ-12800 Prague 2 (Czech Republic); Jakubek, Jan; Krejci, Frantisek; Zemlicka, J. [Institute of Experimental and Applied Physics, Czech Technical University in Prague, Horska 3a/22, CZ-12800 Prague 2 (Czech Republic); Horacek, M.; Radlicka, T.; Vlcek, I. [Institute of Scientific Instruments AS CR, v.v.i., Kralovopolska 147, 61264 Brno (Czech Republic)

2011-05-15

177

Coincidence imaging system with electron optics  

International Nuclear Information System (INIS)

As a part of multiple-detector system for coincidence instrumental neutron activation analysis (CINAA) a new method which includes a devoted electron optic unit has been built. In order to achieve higher sensitivity, enhanced contrast and higher spatial resolution the new coincidence imaging arrangement newly incorporates to electron optic unit, source, the gamma detector and the Timepix electron detector. The electron optic unit can be configured for different electron energies. The description of the assembled apparatus, calibration and performance for different electron energies are presented.

178

Coincidence imaging system with electron optics  

Science.gov (United States)

As a part of multiple-detector system for coincidence instrumental neutron activation analysis (CINAA) a new method which includes a devoted electron optic unit has been built. In order to achieve higher sensitivity, enhanced contrast and higher spatial resolution the new coincidence imaging arrangement newly incorporates to electron optic unit, source, the gamma detector and the Timepix electron detector. The electron optic unit can be configured for different electron energies. The description of the assembled apparatus, calibration and performance for different electron energies are presented.

Kroupa, Martin; Jakubek, Jan; Krejci, Frantisek; Zemlicka, J.; Horacek, M.; Radlicka, T.; Vlcek, I.

2011-05-01

179

Evaluation of Pacific White Shrimp (Litopenaeus vannamei) Health during a Superintensive Aquaculture Growout Using NMR-Based Metabolomics  

OpenAIRE

Success of the shrimp aquaculture industry requires technological advances that increase production and environmental sustainability. Indoor, superintensive, aquaculture systems are being developed that permit year-round production of farmed shrimp at high densities. These systems are intended to overcome problems of disease susceptibility and of water quality issues from waste products, by operating as essentially closed systems that promote beneficial microbial communities (biofloc). The re...

Schock, Tracey B.; Duke, Jessica; Goodson, Abby; Weldon, Daryl; Brunson, Jeff; Leffler, John W.; Bearden, Daniel W.

2013-01-01

180

Electron beam channel for photon tagging system  

International Nuclear Information System (INIS)

An electron beam channel dedicated to the photon tagging system has been constructed at the 1.3 GeV electron Synchrotron, Institute for Nuclear Study, University of Tokyo. Electron beams with intensities up to 3 x 109 e-/sec have been extracted by the Piccioni method. The tagged photon beam in the #betta#3 and the Bremmstrahlung photon beam of full intensity in the #betta#2 can be used simultaneously. In this report, brief descriptions on the extraction system, the transport system, the characteristics of the extracted electron beam, and an operational manual are presented. (author)

181

NATIONAL ELECTRONIC DISEASE SURVEILLANCE SYSTEM (NEDSS)  

Science.gov (United States)

The National Electronic Disease Surveillance System (NEDSS) project is a public health initiative to provide a standard-based, integrated approach to disease surveillance and to connect public health surveillance to the burgeoning clinical information systems infrastructure. NEDS...

182

The Packing System of Electronical learning objects  

OpenAIRE

The subject of this job is „The Packing System of Electronical learning objects“. The main purpose of this job consists of research what is necessary to make the electronical learning course become totally independent from LMS; of the Project and the realization of the tool, which would allow demonstrating the quality of creating this type of course. Universal systems, able to create every necessary elements for the electronical learning allow to produce learning courses and other related...

Liekis, Ric?ardas

2006-01-01

183

Control system for JAERI Free Electron Laser  

International Nuclear Information System (INIS)

A control system comprising of the personal computers network and the CAMAC stations for the JAERI Free Electron Laser is designed and is in the development stage. It controls the equipment and analyzes the electron and optical beam experiments. The concept and the prototype of the control system are described. (author)

184

Prototype model of electronic toll system  

OpenAIRE

In some segments electronic toll system based on satellite technology is quite different from the toll payment procedures that we know today. The new system is based on an intelligent device in a vehicle and on a number of virtual billing and control points that cover the road network. Main advantage of the new system is simultaneously tolling which base on the principle 'Pay as you drive', without stopping or slowing down your vehicle. That kind of electronic toll system will probabl...

Alfirevic?, Igor

2008-01-01

185

Bioactivity of phytochemicals in some lesser-known plants and their effects and potential applications in livestock and aquaculture production systems.  

Science.gov (United States)

Livestock and aquaculture production is under political and social pressure, especially in the European Union (EU), to decrease pollution and environmental damage arising due to animal agriculture. The EU has banned the use of antibiotics and other chemicals, which have been shown to be effective in promoting growth and reducing environment pollutants because of the risk caused to humans by chemical residues in food and by antibiotic resistance being passed on to human pathogens. As a result of this, scientists have intensified efforts in exploiting plants, plant extracts or natural plant compounds as potential natural alternatives for enhancing the livestock productivity. This paper discusses work on the effects of various phytochemicals and plant secondary metabolites in ruminant and fish species. The focus is on (i) plants such as Ananas comosus (pine apple), Momordica charantia (bitter gourd) and Azadirachta indica (neem) containing anthelmintic compounds and for their use for controlling internal parasites; (ii) plants containing polyphenols and their applications for protecting proteins from degradation in the rumen, increasing efficiency of microbial protein synthesis in rumen and decreasing methane emission; for using as antioxidants, antibacterial and antihelmintic agents; and for changing meat colour and for increasing n-3 fatty acids and conjugated linoleic acid in meat; (iii) saponin-rich plants such as quillaja, yucca and Sapindus saponaria for increasing the efficiency of rumen fermentation, decreasing methane emission and enhancing growth; for producing desired nutritional attributes such as lowering of cholesterol in monogastric animals; for increasing growth of fish (common carp and Nile tilapia) and for changing male to female ratio in tilapia; and for use as molluscicidal agents; (iv) Moringa oleifera leaves as a source of plant growth factor(s), antioxidants, beta-carotene, vitamin C, and various glucosinolates and their degraded products for possible use as antibacterial, antioxidant, anticarcinogenic and antipest agents; (v) Jatropha curcas toxic variety with high levels of various phytochemicals such as trypsin inhibitor, lectin, phytate and phorbol esters in seeds limiting the use of seed meal in fish and livestock diets; and the use of phorbol esters as bio-pesticidal agent; and (vi) lesser-known legumes such as Entada phaseoloides seeds containing high levels of trypsin inhibitor and saponins, Sesbania aculeate seeds rich in non-starch polysaccharides and Mucuna pruriens var. utilis seeds rich in l-3,4-dihydroxyphenylalanine and their potential as fish feed; Cassia fistula seeds as a source of antioxidants; and the use of Canavalia ensiformis, C. gladiata and C. virosa seeds containing high levels of trypsin inhinitor, lectins and canavanine. The paper also presents some challenges and future areas of work in this field. PMID:22444893

Makkar, H P S; Francis, G; Becker, K

2007-10-01

186

'Halophyte filters': the potential of constructed wetlands for application in saline aquaculture.  

Science.gov (United States)

World consumption of seafood continues to rise, but the seas and oceans are already over-exploited. Land-based (saline) aquaculture may offer a sustainable way to meet the growing demand for fish and shellfish. A major problem of aquaculture is nutrient waste, as most of the nutrients added through feed are released into the environment in dissolved form. Wetlands are nature's water purifiers. Constructed wetlands are commonly used to treat contaminated freshwater effluent. Experience with saline systems is more limited. This paper explores the potential of constructed saline wetlands for treating the nutrient-rich discharge from land-based saline aquaculture systems. The primary function of constructed wetlands is water purification, but other ancillary benefits can also be incorporated into treatment wetland designs. Marsh vegetation enhances landscape beauty and plant diversity, and wetlands may offer habitat for fauna and recreational areas. Various approaches can be taken in utilizing plants (halophytes, macro-algae, micro-algae) in the treatment of saline aquaculture effluent. Their strengths and weaknesses are reviewed here, and a conceptual framework is presented that takes into account economic and ecological benefits as well as spatial constraints. Use of the framework is demonstrated for assessing various saline aquaculture systems in the southwestern delta region of the Netherlands. PMID:23488001

De Lange, H J; Paulissen, M P C P; Slim, P A

2013-01-01

187

A Comparative Assessment of Hydroponically Grown Cereal Crops for the Purification of Aquaculture Wastewater and the Production of Fish Feed  

OpenAIRE

Hydroponically grown wheat, barley and oats were examined for their ability to remove nutrients from aquaculture wastewater. Wheat, barley and oats seeds were germinated in water in a hydroponics system. The seedlings then received wastewater from an aquaculture system stocked with Arctic charr. During the experiment, the crops grew rapidly and fairly uniformly and showed no signs of mineral deficiency although fungal growth was evident. The average crop heights and yields at harvest were 19....

Snow, A. M.; Ghaly, Abdel E.

2008-01-01

188

Electron transport in molecular systems  

International Nuclear Information System (INIS)

Large-scale quantum electronic structure calculations coupled with nonequilibrium Green function theory are employed for determining quantum conductance on practical length scales. The combination of state-of-the-art quantum mechanical methods, efficient numerical algorithms, and high performance computing allows for realistic evaluation of properties at length scales that are routinely reached experimentally. Two illustrations of the method are presented. First, quantum chemical calculations using up to 104 basis functions are used to investigate the amphoteric doping of carbon nanotubes by encapsulation of organic molecules. As a second example, we investigate the electron transport properties of a Si/organic molecule/Si junction using a numerically optimized basis

189

Sediment quality and production data of black tiger shrimp (Penaeus monodon) culture under Code of Conduct for Responsible Shrimp Aquaculture (CoC) system and ordinary system of intensive shrimp farms  

OpenAIRE

The study of sediment qualities and production data of black tiger shrimp (Penaeus monodon) culture was carried out in 5 ponds practised following CoC guideline (CoC: “Code of Conduct for Responsible Shrimp Aquaculture”) and in 10 ponds practised following common guideline of ordinary intensive farm (OIF). All the ponds were located in Songkhla and Nakhon Si Thammarat provinces and the study period was during March 2003-January 2004. It was found that sediment qualities (organic matter as...

Klaysri, S.; Pornpinidvorakul, P.; Keawtawee, T.; Songsangjinda, P.; Muangyao, P.; Limsuwan, C.

2005-01-01

190

Vertical Integration in the Taiwan Aquaculture Industry  

Directory of Open Access Journals (Sweden)

Full Text Available The study aims to improve the distribution channels in the Taiwanaquaculture industry through a better vertical integration. This studyis derived from a need to improve the distribution performance ofagricultural-based industries in response to increasing food demandsin Asia and elsewhere. Based on a four-by-eight matrix derived fromboth a value chain and a service profit chain, thirty different strategiesare developed. This development is based on key success factors andstrategies for vertical integration interviewed and cited in the literatures.The findings are identified by applying the Gray Relational Analysis(GRA. For this study, the key success factors for aquaculture wholesalemarkets include the communication, integration and cohesion ofopinion within the wholesale market; government support; andmutualtrust between members of the vertical integration scheme. The suitablevertical integration strategies are an improved safety and hygiene inspectionof aquaculture products, accuracy of aquaculture product categorization,and precision in product weighing.

Tzong-Ru Lee (Jiun-Shen

2011-12-01

191

High performance electron processing systems  

International Nuclear Information System (INIS)

Many of the processes of immediate interest for commercial electron curing require large, single pass doses at high speed. The machine designer is faced with some practical upper limits to the dose rate (or electron current density) which can be used efficiently by the chemistry being initiated in the product. In addition, he must pay attention to the temperature excursions in the product due to the relatively low glass transition temperatures or softening temperatures in the substrates of interest. A new family of processors is described capable of delivering up to one megarad at 1500 meters per minute (typically 10 megarads at 150 m/minute). Product temperature excursions are controlled by the use of a shielded drum located within the processor Selfshield. Considerations of the real time diagnosis and control of these processors in production application are discussed, along with typical uniformity and penetration performance in the product

192

High performance electron processing systems  

International Nuclear Information System (INIS)

Many of the processes of immediate interest for commercial electron curing require large, single pass doses at high speed. The machine designer is faced with some practical upper limits to the dose rate (or electron current density) which can be used efficiently by the chemistry being initiated in the product. In addition, he must pay attention to the temperature excursions in the product due to the relatively low glass transition temperatures or softening temperatures in the substrates of interest. A new family of processors is described capable of delivering up to one megarad at 1500 meters per minute (typically 10 megarads at 150 m/minute). Product temperature excursions are controlled by the use of a shielded drum located within the processor. Considerations of the real time diagnosis and control of these processors in production application are discussed, along with typical uniformity and penetration performance in the product. (author)

193

Increased competition for aquaculture from fisheries : does improved fisheries management limit aquaculture growth?  

DEFF Research Database (Denmark)

The global fisheries sector has been characterized by three main trends over the last 2–3 decades; fish stocks have been overexploited and supply from wild fisheries is stagnating; fisheries management has improved slowly with the aims of achieving biological sustainability and rent maximization; and supplies from aquaculture have grown continuously. In this paper, the impact of improved fisheries management on aquaculture growth is studied assuming perfect substitution between farmed and wild fish. We find that improved fisheries management, ceteris paribus, reduces the growth potential of global aquaculture in markets where wild fisheries constitute a large share of total supply.

Jensen, Frank; Nielsen, Max

2014-01-01

194

Cultivable intestinal microbiota of yellowtail juveniles (Seriola lalandi) in an aquaculture system / Microbiota intestinal cultivable de juveniles de dorada (Seriola lalandi) en un sistema de acuicultura  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: English Abstract in spanish La dorada ("yellowtail", Seriola lalandi) ha sido cultivada durante los últimos años, y su expansión se ha debido al mayor conocimiento científico-técnico así como a la creciente demanda, convirtiéndose en una promisoria especie para la acuicultura. Dado que el conocimiento de la microbiota intestin [...] al de esta especie es muy limitado, el objetivo de este estudio es describir las poblaciones bacterianas asociadas al tracto intestinal de Seriola lalandi cultivada en Chile. La composición de la microbiota fue analizada en dos etapas de crecimiento diferenciadas por peso y parámetros como SGR y FCR. Los juveniles (peso inicial promedio 7.33 ± 0.30 g) y pre-adultos (81.7 ± 19.0 g) fueron alimentados con dieta comercial por 33 y 50 días, respectivamente. Las primeras muestras fueron recolectadas al término del primer ensayo en ejemplares de 50 g app., y la segunda muestra fue tomada al término del segundo ensayo en peces de 370 g app. La composición de la microbiota fue examinada mediante aislamiento convencional en medio de cultivo de Agar Tripticasa Soya (TSA) seguido de secuenciación e identificación por 16S rRNA. Un total de dieciséis géneros fueron identificados, donde Pseudomonas, Vibrio y Staphylococcus fueron los géneros predominantes en peces de 50 g, mientras que Microbacterium y Francisella fueron los géneros predominantes en los peces de 370 g. Se determinó que la composición de la microbiota se ajustó a diferentes arreglos en función del tamaño del hospedero, donde los únicos géneros compartidos fueron Bacillus y Vibrio. El conocimiento de la microbiota intestinal de Seriola lalandi es el primer paso para explorar el adecuado manejo de la misma, así como el desarrollo de probióticos y también obtener referencias de la microbiota de peces sanos en condiciones de cultivo. Abstract in english The yellowtail (Seriola lalandi) has been farmed for many years and is becoming a promising aquaculture species. Knowledge of the intestinal microbiota of this species is very limited. Thus, the aim of this study is to describe the bacterial populations associated with the intestinal tract of Seriol [...] a lalandi reared in Chile. The microbiota composition was analyzed at two growth stages distinguished by weight and parameters such as Specific Growth Rate (SGR) and Feed Conversion Ratio (FCR). Juveniles (mean initial weight 7.33 ± 0.30 g) and pre-adults (81.7 ± 19.0 g) were fed with commercial diet for 33 and 50 days, respectively. The first intestinal samples were collected at the end of Trial 1 from specimens weighing approximately 50 g while the second samples were obtained at the end of Trial 2 from specimens weighing approximately 370 g. The microbiota composition was examined using conventional isolation in Tryptic Soy Agar (TSA) followed by 16S rRNA sequencing and identification. In total, 16 genera were identified. Pseudomonas, Vibrio and Staphylococcus were the predominant genera in fish at the 50 g stage, whereas Microbacterium and Francisella were the predominant genera in the 370 g stage. The microbiota composition showed different assemblages, depending on host size, with Bacillus and Vibrio being the only genera that were shared. Knowledge of the intestinal microbiota of Seriola lalandi is the first step in the exploration of microbiota management and the development of probiotics, as well as in the identification of the bacterial populations in healthy fish under cultured conditions.

Eduardo, Aguilera; Gabriel, Yany; Jaime, Romero.

2013-07-01

195

Electronic states in systems of reduced dimensionality  

International Nuclear Information System (INIS)

This report briefly discusses the following research: magnetically modulated systems, inelastic magnetotunneling, ballistic transport review, screening in reduced dimensions, raman and electron energy loss spectroscopy; and ballistic quantum interference effects. (LSP)

196

Magnetic impurity in correlated electrons system  

OpenAIRE

We study a magnetic impurity embedded in a correlated electron system using the density-matrix renormalization group method. The correlated electron system is described by the one-dimensional Hubbard model. At half filling, we confirm that the binding energy of the singlet bound state increases exponentially in the weak-coupling regime and decreases inversely proportional to the correlation in the strong-coupling regime. The spin-spin correlation shows an exponential decay w...

Nishimoto, S.; Fulde, P.

2007-01-01

197

Recommendations for practical measures to mitigate the impact of aquaculture on the environment in three areas of the Philippines  

OpenAIRE

An assessment of the severity and extent of aquaculture impact and the estimation of sustainable carrying capacity were undertaken in three areas of the Philippines - Bolinao (marine site), Dagupan, (brackishwater) and Taal Lake (freshwater). This paper describes the potential mitigating measures that could be taken to reduce nutrient release from aquaculture, increase nutrient uptake using extractive species, and possible early warning systems for critical states of the tide when there is re...

Tarzan Legovi?; Guttorm Christensen; Rune Palerud; Patrick White; Regie Regpala

2008-01-01

198

Recommendations for practical measures to mitigate the impact of aquaculture on the environment in three areas of the Philippines  

Directory of Open Access Journals (Sweden)

Full Text Available An assessment of the severity and extent of aquaculture impact and the estimation of sustainable carrying capacity were undertaken in three areas of the Philippines - Bolinao (marine site, Dagupan, (brackishwater and Taal Lake (freshwater. This paper describes the potential mitigating measures that could be taken to reduce nutrient release from aquaculture, increase nutrient uptake using extractive species, and possible early warning systems for critical states of the tide when there is reduced flushing.

Tarzan Legovi?

2008-12-01

199

Probiotic effects on cobia Rachycentron canadum larvae reared in a recirculating aquaculture system / Efectos probióticos sobre las larvas de cobia Rachycentron canadum criadas en un sistema de recirculación de agua  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: English Abstract in spanish Cobia (Rachycentron canadum) es una especie de pez marino con buen potencial para la maricultura. Este estudio analiza los efectos del probiótico Bacillus spp. sobre el desempeño de las larvas de cobia criadas en un sistema de recirculación de agua (RAS). Las larvas fueron sembradas en dos RAS indep [...] endientes durante 26 días después de la eclosión. Uno de los sistemas (tratamiento experimental) recibió la adición de un probiótico comercial que consiste en B. subtilis, B. licheniformis y B. pumilus directamente en el agua y por alimento vivo. La sobrevivencia, peso final y calidad del agua no se vieron afectados por los probióticos. Los resultados mostraron que las larvas del tratamiento probiótico presentaron una mayor resistencia al estrés por estrés salino. El análisis inmunohistoquímico mostró una mayor expresión de CD4 en el tratamiento probiótico. Estos resultados sugieren que estos probióticos utilizados en las larvas de cobia en RAS tienen un potencial impacto estimulante sobre la diferenciación del sistema inmunológico y aumenta la resistencia al estrés de las larvas de cobia. Abstract in english Cobia (Rachycentron canadum) is a marine finfish with good potential for mariculture. This study analyzes the effects of probiotic Bacillus spp. on the performance of cobia larvae reared in a recirculating aquaculture system (RAS). Larvae were stocked into two independent RAS for 26 days after hatch [...] ing. One of the systems (Probiotic treatment) received the addition of a commercial probiotic consisting of B. subtilis, B. licheniformis and B. pumilus directly into the water and by live feed. Survival, final weight and water quality were not affected by probiotics. Results showed larvae of the probiotic treatment demonstrated a greater resistance to salinity stress. Immunohistochemical analysis showed a higher expression of CD4 in probiotic treatment. These results suggest that Bacillus spp. probiotics used in RAS have a potential stimulating impact on immune system differentiation and increases salinity stress resistance of cobia larvae.

M. Angélica, Garrido-Pereira; Michael, Schwarz; Brendan, Delbos; Ricardo V, Rodrigues; Luis, Romano; Luís, Sampaio.

1169-11-01

200

Corrosion Reliability of Electronic Systems  

DEFF Research Database (Denmark)

Inherently two factors namely multi-material usage and potential bias makes electronic devices susceptible to corrosion if exposed to humid conditions. The problem is compounded today due to miniaturization and contamination effects. The reduction in size of the components and close spacing on a Printed Circuit Board (PCB) for high density packing has greatly increased the risk of corrosion under humid conditions. An important issue is the failures due to electrolytic metal migration. This paper describes an investigation of the electrolytic migration of Sn-Pb solder lines on PCBs in humid environments under applied potential conditions. Studies were carried out using two electrode potentiostatic polarization experiments and measuring the resulting current due to electrolytic migration. The surface morphology of the electrodes before and after migration testing was investigates using SEM and EDS. An in-service failure of a Ceramic Capacitor due to electrolytic migration in humid environments is also presented.

Ambat, Rajan; Jensen, Stine G.

2008-01-01

201

Quantum-based electronic devices and systems selected topics in electronics and systems, v.14  

CERN Document Server

This volume includes highlights of the theories and experimental findings that underlie essential phenomena occurring in quantum-based devices and systems as well as the principles of operation of selected novel quantum-based electronic devices and systems. A number of the emerging approaches to creating new types of quantum-based electronic devices and systems are also discussed.

Dutta, Mitra

1998-01-01

202

THE STATUS OF AQUACULTURE IN THE WORLD AND IN EUROPE  

Directory of Open Access Journals (Sweden)

Full Text Available During the past few years, several authors have presented the production data and the problems in Croatian aquaculture and suggested measures for improvements. Some of these authors referred to some sectors of aquaculture in the world. This paper reports basic statistical data of the Food and Agriculture Organization (FAO, United Nations of the world aquaculture during the period of 1990–1999. The annual growth rate in that period averaged about 10%, and in the year 1999 the aquaculture provided 31.7% of the world needs for aquatic products. The total production and industrialization of aquaculture will continue. Planning of aquaculture development in Croatia and the preparations for joining the European Economic Community must take into account the status of aquaculture and trends in the world, the common fishery policy of EEC (green document, the production in EEC member states and EEC–candidate states and especially the production in neighboring countries. The number, the size and the strength of organizational structures helping the development of aquaculture in EEC are showing these factors to be of decisive importance for the future of sustainable aquaculture in Croatia, too. The very low fish consumption in the country is a negative health factor for the Croatian citizens and it emphasizes the importance of faster development of aquaculture. The paper is intended to stimulate improvements in the aquaculture development strategy, to promote more positive approach towards this food production sector and to speed up its successfulness in Croatia.

Nikola Fijan

2002-06-01

203

Electron beam size measurements in the Fermilab Electron Cooling System  

Energy Technology Data Exchange (ETDEWEB)

The Fermilab Electron Cooling Project requires a straight trajectory and constant beam size to provide maximum cooling of the antiprotons in the Recycler. A measurement system was developed using movable apertures and steering bumps to measure the beam size in a 20m long, nearly continuous, solenoid. This paper will focus on results of these measurements of the beam size and the difficulties in making those measurements.

Kroc, T.K.; Burov, A.V.; Bolshakov, T.B.; Shemyakin, A.; /Fermilab; Seletskiy, S.M.; /Rochester U.

2005-09-01

204

PROTEOMICS in aquaculture : Applications and trends  

DEFF Research Database (Denmark)

Over the last forty years global aquaculture presented a growth rate of 6.9% per annum with an amazing production of 52.5million tonnes in 2008, and a contribution of 43% of aquatic animal food for human consumption. In order to meet the world's health requirements of fish protein, a continuous growth in production is still expected for decades to come. Aquaculture is, though, a very competitive market, and a global awareness regarding the use of scientific knowledge and emerging technologies to obtain a better farmed organism through a sustainable production has enhanced the importance of proteomics in seafood biology research. Proteomics, as a powerful comparative tool, has therefore been increasingly used over the last decade to address different questions in aquaculture, regarding welfare, nutrition, health, quality, and safety. In this paper we will give an overview of these biological questions and the role of proteomics in their investigation, outlining the advantages, disadvantages and future challenges. A brief description of the proteomics technical approaches will be presented. Special focus will be on the latest trends related to the aquaculture production of fish with defined nutritional, health or quality properties for functional foods and the integration of proteomics techniques in addressing this challenging issue. This article is part of a Special Issue entitled: Farm animal proteomics.

Rodrigues, Pedro M.; Silva, Tomé S.

2012-01-01

205

Electron correlation energy in confined two-electron systems  

International Nuclear Information System (INIS)

Radial, angular and total correlation energies are calculated for four two-electron systems with atomic numbers Z=0-3 confined within an impenetrable sphere of radius R. We report accurate results for the non-relativistic, restricted Hartree-Fock and radial limit energies over a range of confinement radii from 0.05-10a0. At small R, the correlation energies approach limiting values that are independent of Z while at intermediate R, systems with Z?1 exhibit a characteristic maximum in the correlation energy resulting from an increase in the angular correlation energy which is offset by a decrease in the radial correlation energy.

206

Quantum phase transitions in electronic systems  

CERN Document Server

Quantum phase transitions occur at zero temperature when some non-thermal control-parameter like pressure or chemical composition is changed. They are driven by quantum rather than thermal fluctuations. In this review we first give a pedagogical introduction to quantum phase transitions and quantum critical behavior emphasizing similarities with and differences to classical thermal phase transitions. We then illustrate the general concepts by discussing a few examples of quantum phase transitions occurring in electronic systems. The ferromagnetic transition of itinerant electrons shows a very rich behavior since the magnetization couples to additional electronic soft modes which generates an effective long-range interaction between the spin fluctuations. We then consider the influence of rare regions on quantum phase transitions in systems with quenched disorder, taking the antiferromagnetic transitions of itinerant electrons as a primary example. Finally we discuss some aspects of the metal-insulator transit...

Vojta, T

1999-01-01

207

Bioinspired electron-transfer systems and applications  

International Nuclear Information System (INIS)

Bioinspired electron-transfer systems including artificial photosynthesis and respiration are presented herein together with some of their applications. First, multi-step electron-transfer systems composed of electron donor-acceptor ensembles have been developed, mimicking functions of the photosynthetic reaction center. However, a significant amount of energy is lost during the multi-step electron-transfer processes. Then, as an alternative to conventional charge-separation functional molecular models based on multi-step long-range electron transfer within redox cascades, simple donor-acceptor dyads have been developed to attain along-lived and high energy charge-separated state without significant loss of excitation energy, by fine control of the redox potentials and of the geometry of donor-acceptor dyads that have small reorganization energies of electron transfer. Such simple molecular dyads, capable of fast charge separation but extremely slow charge recombination, have significant advantages with regard to synthetic feasibility, providing a variety of applications including construction of organic solar cells and development of efficient photo-catalytic systems for the solar energy conversion. An efficient four-electron reduction of dioxygen to water by one-electron reductants such as ferrocene derivatives as well as by an NADH analog has also been achieved as a respiration model by using a cofacial dicobalt porphyrin that can form the ?-peroxo Co(III)-O2hat can form the ?-peroxo Co(III)-O2Co(III) complex. The catalytic mechanism of the four-electron reduction of dioxygen has been clarified based on the detailed kinetic study and the detection of the intermediate. (author)

208

Evaluation on Biofilter in Recirculating Integrated Multi-Trophic Aquaculture  

Directory of Open Access Journals (Sweden)

Full Text Available Integrated multi-trophic aquaculture pays more attention as a bio-integrated food production system that serves as a model of sustainable aquaculture, minimizes waste discharge, increases diversity and yields multiple products. The objectives of this research were to analyze the efficiency of total ammonia nitrogen biofiltration and its effect on carrying capacity of fish rearing units. Pilot-scale bioreactor was designed with eight run-raceways (two meters of each that assembled in series. Race 1-3 were used to stock silky worm (Tubifex sp as detrivorous converter, then race 4-8 were used to plant three species of leaf-vegetable as photoautotrophic converters, i.e; spinach (Ipomoea reptana, green mustard (Brassica juncea and basil (Ocimum basilicum. The three plants were placed in randomized block design based on water flow direction. Mass balance of nutrient analysis, was applied to figure out the efficiency of bio-filtration and its effect on carrying capacity of rearing units. The result of the experiment showed that 86.5 % of total ammonia nitrogen removal was achieved in 32 days of culturing period. This efficiency able to support the carrying capacity of the fish tank up to 25.95 kg/lpm with maximum density was 62.69 kg/m3 of fish biomass productionDoi: http://dx.doi.org/10.12777/ijse.4.2.2013.80-85 [How to cite this article: Sumoharjo, S.  and Maidie, A. (2013. Evaluation on Biofilter in Recirculating Integrated Multi-Trophic Aquaculture.  International Journal of  Science and Engineering, 4(2,80-85. Doi: http://dx.doi.org/10.12777/ijse.4.2.2013.80-85

Asfie Maidie

2013-06-01

209

Radial conical electron-optical systems  

International Nuclear Information System (INIS)

Electron-optical systems formed by conical electrodes or pole tips with the internal surfaces made in the from of parts of straight circular cone are investigated. The electric potential distribution in radial conical electron-optical elements is determined analytically. Expressions are obtained for paraxial tra ectories of charged particles as well as focus distances and focus positions of radial lenses. Achromatism conditions are considered

210

Radial conical electron-optical systems  

Energy Technology Data Exchange (ETDEWEB)

Electron-optical systems formed by conical electrodes or pole tips with the internal surfaces made in the from of parts of straight circular cone are investigated. The electric potential distribution in radial conical electron-optical elements is determined analytically. Expressions are obtained for paraxial tra ectories of charged particles as well as focus distances and focus positions of radial lenses. Achromatism conditions are considered.

Baranova, L.A.; Yavor, S.Ya.

1984-10-01

211

Electron motions in aqueous systems - a survey  

International Nuclear Information System (INIS)

This paper reviews current experimental and theoretical information about the immediate fate of electrons generated in aqueous systems by ionizing radiation or photolysis of solutes. The applications of spur diffusion theory to pulse radiolysis and flash photolysis results are considered, with brief accounts of related developments in connection with time-dependent rate constants, the radiation sensitivity of large biological targets, and long-range electron interactions including tunneling. (author)

212

Relaxation of an Electron System : Conserving Approximation  

OpenAIRE

The dynamic response of an interacting electron system is determined by an extension of the relaxation-time approximation forced to obey local conservation laws for number, momentum and energy. A consequence of these imposed constraints is that the local electron equilibrium distribution must have a space- and time-dependent chemical potential, drift velocity and temperature. Both quantum kinetic and semi-classical arguments are given, and we calculate and analyze the corres...

Atwal, G. S.; Ashcroft, N. W.

2001-01-01

213

Induced superconductivity in 2D electronic systems  

OpenAIRE

The approach applicable for spatially inhomogeneous and time-dependent problems associated with the induced superconductivity in low dimensional electronic systems is developed. This approach is based on the Fano--Anderson model which describes the decay of a resonance state coupled to a continuum. We consider two types of junctions made of a ballistic 2D electron gas placed in a tunnel finite-length contact with a bulk superconducting leads. We calculate the spectrum of the...

Kopnin, N. B.; Melnikov, A. S.

2011-01-01

214

Inelastic Electron Lifetime in Disordered Mesoscopic Systems  

OpenAIRE

The inelastic quasiparticle lifetime due to the electron-electron interaction (out-scattering time in the kinetic equation formalism) is calculated for finite metallic diffusive systems (quantum dots) in the whole range of parameters. Both cases of ``continuous'' (the inelastic level broadening much exceeds the mean level spacing) and ``discrete'' spectrum are analyzed. In particular, crossover between one- and zero-dimensional regimes is studied in detail. In the case of co...

Blanter, Yaroslav M.

1996-01-01

215

Molecular electronics device modeling for system design.  

OpenAIRE

We have used the Breit-Wigner resonance formula to model a class of molecular electronics devices with the aim to establish an abstract model for a molecular electronic device that can be used in a general cross bar architecture of future nanoelectronic systems. We show that the molecular I-V curves can be characterized by a very small number of variables including the couplings between the contact and leads.

Lei, Ci; Pamunuwa, Dinesh B.; Bailey, Stephen; Lambert, Colin

2007-01-01

216

Electron localization in one-dimensional systems  

International Nuclear Information System (INIS)

The pure regional localization and the global localization have been investigated via the inverse participation ratio and te moment analysis. If the envelop function of a localized state is more complicated than the simple exponential function e sup(-r/xi), the inverse participation ratio is inadequate to describe the localization properties of an electron. This is the case discovered recently in a stereo-irregular chain fo atoms including the electron-electron interaction and the structure disorder. The localization properties in this system are analysed in terms of the moments. (Author)

217

Electron-ion-x-ray spectrometer system  

Energy Technology Data Exchange (ETDEWEB)

The authors describe a spectrometer system developed for electron, ion, and x-ray spectroscopy of gas-phase atoms and molecules following inner-shell excitation by tunable synchrotron radiation. The spectrometer has been used on beamline X-24A at the National Synchrotron Light Source for excitation-dependent studies of Ar L-shell and K-shell photoexcitation and vacancy decay processes. The instrumentation and experimental methods are discussed, and examples are given of electron spectra and coincidence spectra between electrons and fluorescent x-rays.

Southworth, S.H.; Deslattes, R.D. [National Inst. of Standards and Technology, Gaithersburg, MD (United States); MacDonald, M.A. [SERC, Warrington (United Kingdom). Daresbury Lab.; LeBrun, T. [Argonne National Lab., IL (United States)

1993-10-01

218

A Flexible Electronic Commerce Recommendation System  

Science.gov (United States)

Recommendation systems have become very popular in E-commerce websites. Many of the largest commerce websites are already using recommender technologies to help their customers find products to purchase. An electronic commerce recommendation system learns from a customer and recommends products that the customer will find most valuable from among the available products. But most recommendation methods are hard-wired into the system and they support only fixed recommendations. This paper presented a framework of flexible electronic commerce recommendation system. The framework is composed by user model interface, recommendation engine, recommendation strategy model, recommendation technology group, user interest model and database interface. In the recommender strategy model, the method can be collaborative filtering, content-based filtering, mining associate rules method, knowledge-based filtering method or the mixed method. The system mapped the implementation and demand through strategy model, and the whole system would be design as standard parts to adapt to the change of the recommendation strategy.

Gong, Songjie

219

Electronic instrumentation system for pulsed neutron measurements  

International Nuclear Information System (INIS)

An essential point of pulsed neutron measurement of thermal neutron parameters for different materials is the registration of the thermal neutron die-away curve after a fast neutron bursts have been injected into the system. An electronic instrumentation system which is successfully applied for pulsed neutron measurements is presented. An important part of the system is the control unit which has been designed and built in the Laboratory of Neutron Parameters of Materials. (author)

220

Collimation system for electron arc therapy  

International Nuclear Information System (INIS)

An electron collimation system for electron arc therapy treatments consists of a slit collimation system which is movable with the electron beam applicator and is designed to allow for dose compensation in the sagittal direction and a hoop-and-clamp assembly for final field shaping. By correctly designing the shape of the slit in the former and properly adjusting the components of the latter, it is possible to accomplish quite uniform shielding without causing any weight of the shielding material to rest on the patient. The slit collimation system has a specially shaped aperture for confining the radiation beam. The hoop-and-clamp assembly has hoops and clamps which locate shielding over the patient's body. The shielding locating clamps are adjustably movable radially with respect to the hoops. (author)

221

Merging remotely sensed data, models and indicators for a sustainable development of coastal aquaculture in Algeria  

Science.gov (United States)

Finfish cage farming is an economically relevant activity, which exerts pressures on coastal systems and thus require a science-based management, based on the Ecosystem Approach, in order to be carry out in a sustainable way. Within MEDINA project (EU 282977), ocean color data and models were used for estimating indicators of pressures of aquaculture installations along the north African coast. These indicators can provide important support for decision makers in the allocation of new zones for aquaculture, by taking into account the suitability of an area for this activity and minimizing negative environmental effects, thus enhancing the social acceptability of aquaculture. The increase in the number of farms represents a strategic objective for the Algerian food production sector, which is currently being supported by different national initiatives. The case-study presented in this work was carried out in the Gulf of Bejaia. Water quality for aquaculture was first screened based on ocean color CDOM data (http://www.globcolour.info/). The SWAN model was subsequently used to propagate offshore wave data and to derive wave height statistics. On this basis, sub-areas of the Gulf were ranked, according their optimality in respect to cage resistance and fish welfare requirements. At the three best sites an integrated aquaculture impact assessment model was therefore applied: this tool allows one to obtain a detailed representation of fish growth and population dynamics inside the rearing cages, and to simulate the deposition of uneaten food and faeces on the sediment and the subsequent mineralization of organic matter. This integrated model was used to produce a set of indicators of the fish cages environmental interaction under different scenarios of forcings (water temperature, feeding, currents). These model-derived indicators could usefully contribute to the implementation of the ecosystem approach for the management of aquaculture activities, also required by the implementation of the UNEP/MAP ecological approach.

Brigolin, Daniele; Venier, Chiara; Amine Taji, Mohamed; Lourguioui, Hichem; Mangin, Antoine; Pastres, Roberto

2014-05-01

222

Minimizing noise in fiberglass aquaculture tanks: Noise reduction potential of various retrofits  

Science.gov (United States)

Equipment used in intensive aquaculture systems, such as pumps and blowers can produce underwater sound levels and frequencies within the range of fish hearing. The impacts of underwater noise on fish are not well known, but limited research suggests that subjecting fish to noise could result in imp...

223

Electronic system of TBR tokamak device  

International Nuclear Information System (INIS)

The electronics developed as a part of the TBR project, which involves the construction of a small tokamak at the Physics Institute of the University of Sao Paulo, is described. On the basis of tokamak parameter values, the electronics for the toroidal field, ohmic/heating and vertical field systems is presented, including capacitors bank, switches, triggering circuits and power supplies. A controlled power oscilator used in discharge cleaning and pre-ionization is also described. The performance of the system as a function of the desired plasma parameters is discussed. (Author)

224

Method of fabricating a cooled electronic system  

Science.gov (United States)

A method of fabricating a liquid-cooled electronic system is provided which includes an electronic assembly having an electronics card and a socket with a latch at one end. The latch facilitates securing of the card within the socket. The method includes providing a liquid-cooled cold rail at the one end of the socket, and a thermal spreader to couple the electronics card to the cold rail. The thermal spreader includes first and second thermal transfer plates coupled to first and second surfaces on opposite sides of the card, and thermally conductive extensions extending from end edges of the plates, which couple the respective transfer plates to the liquid-cooled cold rail. The extensions are disposed to the sides of the latch, and the card is securable within or removable from the socket using the latch without removing the cold rail or the thermal spreader.

Chainer, Timothy J; Gaynes, Michael A; Graybill, David P; Iyengar, Madhusudan K; Kamath, Vinod; Kochuparambil, Bejoy J; Schmidt, Roger R; Schultz, Mark D; Simco, Daniel P; Steinke, Mark E

2014-02-11

225

Dissociative electron attachment to polyatomic systems  

Science.gov (United States)

In this dissertation, we have investigated molecular dissociation processes induced by electron collisions and addressed the inherent polyatomic effects involved. Dissociative electron attachment is known to be an important decay channel for resonant states formed in low-energy electron-molecule collisions. In analyzing these processes, the community has built an intuition based on studies of diatomics. The simple 1-D picture used in these studies appears to be inadequate for making correct predictions of the nuclear dynamics in the case of polyatomic systems where multiple degrees of freedom come into play. Generally, dissociation processes involve distortions of the molecule's geometry thus lowering its point group symmetry. Symmetry breaking events are known to cause a split of degenerate states causing transformations of the potential energy surfaces' topology; thus, leading to intersurface interactions. It is therefore necessary to introduce the various effects of coupling between the states of the compound system {electron, molecule} into the study of polyatomic molecules dissociation dynamics. Four polyatomic systems of astrophysical, biological and technological relevance have been treated by ab initio methods: acetylene (HCCH), hydrogen cyanide (HCN), hydrogen isocyanide (HNC) and cyano-acetylene (HCCCN). For each molecule, we constructed the complex potential energy surfaces using the complex Kohn variational method, performed nuclear dynamics computations within the multi-configuration time-dependent Hartree formalism and computed the dissociative electron attachment (DEA) cross sections. The dissociation dynamic behavior is discussed and the results are compared to available experimental data.

Chourou, Slim Taieb

226

Magnetoconductivity of two-dimensional electron systems  

Science.gov (United States)

The conductivity sigmaxx(o) of a low-density nondegenerate 2D electron gas is investigated under conditions where hoc ? kBT ? hgamma (oc is the cyclotron frequency and hgamma is the disorder-induced width of the Landau level). Such conditions have been met for electrons on helium surface, and can also be achieved in ultra high quality heterostructures. Because of the random potential of defects, single-electron states of the lowest Landau level form a band of a width hgamma ? hoc. Almost all of these states are localized. Therefore, for ho c ? kBT ? hgamma, the static single-electron conductivity sigma xx(0) may be expected to be equal to zero. Since for o ? gamma the conductivity should decay, on the whole sigma xx(o) has a peak at a finite frequency. From scaling arguments, we show that in the single-electron approximation sigma xx(o) ? omu for o ? 0, with the exponent mu in the range from 0.21 to 0.22, whereas the frequency dependence of the cyclotron resonance absorption peak is non-critical. The far tails of the conductivity peaks are obtained using the method of optimal fluctuation and are shown to be Gaussian. In order to investigate the shape of the low frequency peak and cyclotron resonance absorption peak, we use the method of moments (MOM). In MOM, the low-frequency conductivity is restored from its 14 spectral moments, whereas the cyclotron resonance absorption is restored from the calculated 10 spectral moments using the continuous fraction expansion. In combination with the analytical asymptotics, both expansions converge rapidly with increasing number of included moments, and give numerically accurate results throughout the region of interest. The effect of electron-electron interaction (EEI) on the low frequency conductivity is also investigated. EEI makes the static conductivity finite. For a low-density system, the effect can be described using the notion of a fluctuational field Efl which drives an electron because of electron density fluctuations. Due to this field, spatial diffusion of electrons in a (comparatively strong) random potential of defects gives rise to energy diffusion of each individual electron, with a diffusion coefficient Depsilon = gammae2h/mo c. In combination with the known power-law asymptotic of the single-electron conductivity for sigmase(o) for o ? 0, this allows us to find the static many-electron conductivity sigma me.

Kuehnel, Frank Oliver

227

Control system of Beijing electron positron collider  

International Nuclear Information System (INIS)

The BEPC II project started in summer of 2001 and has passed the National Acceptance Test in July 2009, which is for upgrading the Beijing Electron Positron Collider to reach a higher luminosity and keep its leading position among the same kind of facilities in the world.The BEPC II control system has been re-built which adopted the distribution architecture,and developed with the EPICS (Experimental Physics and Industrial Control System). The BEPC II control system was put into operation in November 2006. Till now it runs well and has reached the design goal. This paper describes the new BEPC II control system. (authors)

228

DESIGN OF ADVANCED ELECTRONIC BIOMEDICAL SYSTEMS  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper we present a review of some of our projects in the field of biomedical electronics, developed at Electronic Devices Laboratory of Polytechnic University of Bari, Italy, within a research program, with the support of national university medical centre. In particular we have proposed a medical electronic-computerized platform for diagnostic use, which allows the doctor to carry out a complete cardio-respiratory control on remote patients in real time. The system has been patented and has been designed to be employed also to real-time rescue in case of emergency without the necessity for data to be constantly monitored by a medical centre, leaving patients free to move. Then we have also examined a low-cost, electronic medical system, designed for the non-invasive continuous real-time monitoring of breathing functions. At last a new system for cardioholter applications, characterized by the possibility to send ECG by Bluetooth to 6 or 12 leads, has been described. All designed systems are characterized by originality and plainness of use, as they planned with a very high level of automation.

Anna Gina Perri

2012-07-01

229

NATIONAL ELECTRONIC INJURY SURVEILLANCE SYSTEM (NEISS)  

Science.gov (United States)

The National Center for Injury Prevention and Control (NCIPC), Centers for Disease Control and Prevention (CDC) is collaborating with the U.S. Consumer Product Safety Commission (CPSC) to expand the National Electronic Injury Surveillance System (NEISS) to collect data on all typ...

230

Soft errors in modern electronic systems  

CERN Document Server

This book provides a comprehensive presentation of the most advanced research results and technological developments enabling understanding, qualifying and mitigating the soft errors effect in advanced electronics, including the fundamental physical mechanisms of radiation induced soft errors, the various steps that lead to a system failure, the modelling and simulation of soft error at various levels (including physical, electrical, netlist, event driven, RTL, and system level modelling and simulation), hardware fault injection, accelerated radiation testing and natural environment testing, s

Nicolaidis, Michael

2010-01-01

231

The SLAC polarized electron source laser system  

International Nuclear Information System (INIS)

The Stanford Linear Collider (SLC) has operated a polarized photocathode electron source and titanium sapphire laser for high energy physics collisions for over 6,500 hours of nearly continuous operation. The laser system for the source has demonstrated > 98.5% total uptime for the duration of the experiment. The laser system uses a pair of titanium sapphire oscillators pumped by frequency doubled YAG lasers to produce 2ns, 250 microJ pulses at wavelengths from 740nm to 870nm

232

Scenarios for Resilient Shrimp Aquaculture in Tropical Coastal Areas  

Directory of Open Access Journals (Sweden)

Full Text Available We contend there are currently two competing scenarios for the sustainable development of shrimp aquaculture in coastal areas of Southeast Asia. First, a landscape approach, where farming techniques for small-scale producers are integrated into intertidal areas in a way that the ecological functions of mangroves are maintained and shrimp farming diseases are controlled. Second, a closed system approach, where problems of disease and effluent are eliminated in closed recirculation ponds behind the intertidal zone controlled by industrial-scale producers. We use these scenarios as two ends of a spectrum of possible interactions at a range of scales between the ecological, social, and political dynamics that underlie the threat to the resilience of mangrove forested coastal ecosystems. We discuss how the analytical concepts of resilience, uncertainty, risk, and the organizing heuristic of scale can assist us to understand decision making over shrimp production, and in doing so, explore their use in the empirical research areas of coastal ecology, shrimp health management and epidemiology, livelihoods, and governance in response to the two scenarios. Our conclusion focuses on a series of questions that map out a new interdisciplinary research agenda for sustainable shrimp aquaculture in coastal areas.

Willem F. de Boer

2010-06-01

233

Probiotics as Antiviral Agents in Shrimp Aquaculture  

OpenAIRE

Shrimp farming is an aquaculture business for the cultivation of marine shrimps or prawns for human consumption and is now considered as a major economic and food production sector as it is an increasingly important source of protein available for human consumption. Intensification of shrimp farming had led to the development of a number of diseases, which resulted in the excessive use of antimicrobial agents, which is finally responsible for many adverse effects. Currently, probiotics are ch...

Bestha Lakshmi; Buddolla Viswanath; Sai Gopal, D. V. R.

2013-01-01

234

Genomics in Eels — Towards Aquaculture and Biology  

OpenAIRE

Freshwater eels (genus Anguilla), especially the species inhabiting the temperate areas such as the European, American and Japanese eels, are important aquaculture species. Although artificial reproduction has been attempted since the 1930s and large numbers of studies have been conducted, it has not yet fully succeeded. Problems in eel artificial breeding are highly diverse, for instance, lack of basic information about reproduction in nature, no appropriate food for larvae, high mortality, ...

Minegishi, Yuki; Henkel, Christiaan V.; Dirks, Ron P.; Den Thillart, Guido E. E. J. M.

2012-01-01

235

Organic matter decomposition in simulated aquaculture ponds  

OpenAIRE

Different kinds of organic and inorganic compounds (e.g. formulated food, manures, fertilizers) are added to aquaculture ponds to increase fish production. However, a large part of these inputs are not utilized by the fish and are decomposed inside the pond. The microbiological decomposition of the organic matter is a critical factor for water quality control and nutrient recycle. Usually, management practices are developed to control the survival and health of the cultured animals and to mai...

Torres Beristain, B.

2005-01-01

236

Probiotics as control agents in aquaculture  

Science.gov (United States)

Infectious diseases constitute a limiting factor in the development of the aquaculture production, and control has solely concentrated on the use of antibiotics. However, the massive use of antibiotics for the control of diseases has been questioned by acquisition of antibiotic resistance and the need of alternative is of prime importance. Probiotics, live microorganisms administered in adequate amounts that confer a healthy effect on the host, are emerging as significant microbial food supplements in the field of prophylaxis.

Geovanny D, Gómez R.; Balcázar, José Luis; Ma, Shen

2007-01-01

237

PCR AS DIAGNOSTIC METHOD IN AQUACULTURE  

OpenAIRE

PCR is an acronym for »polymerase chain reaction«, a technique based on detection and amplification of specific DNA and RNA sequences. It can be applied in diagnostics of hereditary diseases, forensics, population genetics, systematics, bioengineering, evolution biology, and also aquaculture. With this method it is possible to diagnose an array of viral, bacterial and parasitic diseases of fish, shellfish and crustaceans. The advantages of the technique are manifested in rapid obtaining of ...

Ivan?ica Strunjak-Perovi?; Natalija Topi? Popovi?

1999-01-01

238

Electron gun system for NSC KIPT linac  

Science.gov (United States)

In the NSC KIPT linac, a neutron source based on a subcritical assembly driven by a 100 MeV/100 kW electron linear accelerator is under design and development. The linear accelerator needs a new high current electron gun. In this paper, the physical design, mechanical fabrication and beam test of this new electron gun are described. The emission current is designed to be higher than 2 A for the pulse width of 3 ?s with repetition rate of 50 Hz. The gun will operate with a DC high voltage power supply that can provide a high voltage up to 150 kV. Computer simulations and optimizations have been carried out in the design stage, including the gun geometry and beam transport line. The test results of high voltage conditioning and beam test are presented. The operation status of the electron gun system is also included. The basic test results show that the design, manufacture, and operation of the new electron system are basically successful.

Zhou, Zu-Sheng; He, Da-Yong; Chi, Yun-Long

2014-06-01

239

Probiotics as antiviral agents in shrimp aquaculture.  

Science.gov (United States)

Shrimp farming is an aquaculture business for the cultivation of marine shrimps or prawns for human consumption and is now considered as a major economic and food production sector as it is an increasingly important source of protein available for human consumption. Intensification of shrimp farming had led to the development of a number of diseases, which resulted in the excessive use of antimicrobial agents, which is finally responsible for many adverse effects. Currently, probiotics are chosen as the best alternatives to these antimicrobial agents and they act as natural immune enhancers, which provoke the disease resistance in shrimp farm. Viral diseases stand as the major constraint causing an enormous loss in the production in shrimp farms. Probiotics besides being beneficial bacteria also possess antiviral activity. Exploitation of these probiotics in treatment and prevention of viral diseases in shrimp aquaculture is a novel and efficient method. This review discusses the benefits of probiotics and their criteria for selection in shrimp aquaculture and their role in immune power enhancement towards viral diseases. PMID:23738078

Lakshmi, Bestha; Viswanath, Buddolla; Sai Gopal, D V R

2013-01-01

240

Risks of Using Antifouling Biocides in Aquaculture  

Science.gov (United States)

Biocides are chemical substances that can deter or kill the microorganisms responsible for biofouling. The rapid expansion of the aquaculture industry is having a significant impact on the marine ecosystems. As the industry expands, it requires the use of more drugs, disinfectants and antifoulant compounds (biocides) to eliminate the microorganisms in the aquaculture facilities. The use of biocides in the aquatic environment, however, has proved to be harmful as it has toxic effects on the marine environment. Organic booster biocides were recently introduced as alternatives to the organotin compounds found in antifouling products after restrictions were imposed on the use of tributyltin (TBT). The replacement products are generally based on copper metal oxides and organic biocides. The biocides that are most commonly used in antifouling paints include chlorothalonil, dichlofluanid, DCOIT (4,5-dichloro-2-n-octyl-4-isothiazolin-3-one, Sea-nine 211®), Diuron, Irgarol 1051, TCMS pyridine (2,3,3,6-tetrachloro-4-methylsulfonyl pyridine), zinc pyrithione and Zineb. There are two types of risks associated with the use of biocides in aquaculture: (i) predators and humans may ingest the fish and shellfish that have accumulated in these contaminants and (ii) the development of antibiotic resistance in bacteria. This paper provides an overview of the effects of antifouling (AF) biocides on aquatic organisms. It also provides some insights into the effects and risks of these compounds on non-target organisms. PMID:22408407

Guardiola, Francisco Antonio; Cuesta, Alberto; Meseguer, José; Esteban, Maria Angeles

2012-01-01

241

Risks of Using Antifouling Biocides in Aquaculture  

Directory of Open Access Journals (Sweden)

Full Text Available Biocides are chemical substances that can deter or kill the microorganisms responsible for biofouling. The rapid expansion of the aquaculture industry is having a significant impact on the marine ecosystems. As the industry expands, it requires the use of more drugs, disinfectants and antifoulant compounds (biocides to eliminate the microorganisms in the aquaculture facilities. The use of biocides in the aquatic environment, however, has proved to be harmful as it has toxic effects on the marine environment. Organic booster biocides were recently introduced as alternatives to the organotin compounds found in antifouling products after restrictions were imposed on the use of tributyltin (TBT. The replacement products are generally based on copper metal oxides and organic biocides. The biocides that are most commonly used in antifouling paints include chlorothalonil, dichlofluanid, DCOIT (4,5-dichloro-2-n-octyl-4-isothiazolin-3-one, Sea-nine 211®, Diuron, Irgarol 1051, TCMS pyridine (2,3,3,6-tetrachloro-4-methylsulfonyl pyridine, zinc pyrithione and Zineb. There are two types of risks associated with the use of biocides in aquaculture: (i predators and humans may ingest the fish and shellfish that have accumulated in these contaminants and (ii the development of antibiotic resistance in bacteria. This paper provides an overview of the effects of antifouling (AF biocides on aquatic organisms. It also provides some insights into the effects and risks of these compounds on non-target organisms.

José Meseguer

2012-02-01

242

DIAGNOSIS OF AQUACULTURE IN THE MUNICIPALITY OF ALVARADO VERACRUZ, MEXICO  

OpenAIRE

This research aims to analyze the current situation of aquaculture farms in the Municipality of Alvarado, Veracruz, Mexico. During this study, 29 interviews were conducted aimed to the units of aquaculture producers; 24 variables were analyzed within the aspects of the socio-economic, technical, marketing and legal framework. The most relevant results within the legal framework: 21% of units has “National Registration of Fisheries and Aquaculture” (RNPyA) and 7% has “Federal Taxpayer Re...

Lenin Rangel-López; Fabiola Lango-Reynoso; Alberto Asian-Hoyos; María del Refugio Castañeda-Chávez

2014-01-01

243

Analysis of economic and biological factors of waste heat aquaculture  

Energy Technology Data Exchange (ETDEWEB)

A waste heat aqualculture system using extensive culture techniques is currently under investigation at the Oak Ridge National Lab. The system uses nutrients in waste water streams to grow algae and zooplankton which provide feed for fish and clams. A tilapia polyculture association and the freshwater clam Corbicula are the animals cultured in the system. The investigations detailed in this study have been performed to determine the economic and biological fesibility of the system and to examine energy utilization. The economic study indicated that fish producion costs of $0.24/lb were possible. This cost, however, depends upon the fish production rate and food conversion efficiency and could rise to as much as $0.75/lb. The biological studies have examined growth relationships and production potential of the cultured organisms. In the laboratory, growth-temperature optima have been deinfed (32/sup 0/C, with good growth rates between 26 and 34/sup 0/C) for tilapia hybrids. Using cage culture techniques in sewage oxidation ponds, we have obtained production estimates in excess of 50,000 lb/acre/yr. The energy utilization study indicated that, when all energy costs are included, fish from the aquaculture system may require only 35% of the net energy now required for fish products from the ocean. However, the energy requirements also depend on system parameters and could be large as those required for ocean-caught products. The analyses indicate that the system is economically feasible. They also indicate that significant energy savings are possible if waste heat aquaculture products replace ocean-caught products.

Suffern, J. S.; Olszewski, M.

1978-01-01

244

Electron dynamics inside short-coherence systems  

International Nuclear Information System (INIS)

We present theoretical results on electron dynamics inside nanometric systems, where the coherence of the electron ensemble is maintained in a very short region. The contacts are supposed to spoil such a coherence, therefore the interference processes between the carrier wavefunction and the internal potential profile can be affected by the proximity of the contacts. The problem has been analysed by using the Wigner-function formalism. For very short devices, transport properties, such as tunnelling through potential barriers, are significantly influenced by the distance between the contacts

245

Design for Reliability of Power Electronic Systems  

DEFF Research Database (Denmark)

Advances in power electronics enable efficient and flexible processing of electric power in the application of renewable energy sources, electric vehicles, adjustable-speed drives, etc. More and more efforts are devoted to better power electronic systems in terms of reliability to ensure high availability, long lifetime, sufficient robustness, low maintenance cost and low cost of energy. However, the reliability predictions are still dominantly according to outdated models and terms, such as MIL-HDBK-217F handbook models, Mean-Time-To-Failure (MTTF), and Mean-Time-Between-Failures (MTBF). A collection of methodologies based on Physics-of-Failure (PoF) approach and mission profile analysis are presented in this paper to perform reliability-oriented design of power electronic systems. The corresponding design procedures and reliability prediction models are provided. Further on, a case study on a 2.3 MW wind power converter is discussed with emphasis on the reliability critical components IGBTs. Different aspects of improving the reliability of the power converter are mapped. Finally, the challenges and opportunities to achieve more reliable power electronic systems are addressed.

Wang, Huai; Ma, Ke

2012-01-01

246

The Small Explorer power system electronics  

Science.gov (United States)

The power system electronics for the NASA Goddard Space Flight Center Small Explorer Satellites are intended to satisfy various planned missions. The selected topology is a direct energy transfer (DET) system with the battery connected directly to the bus. The shunt control technique is a linear sequential full shunt which provides a simple solar array interface and can support both 3 axis stabilized and spinner satellites. In addition, it can meet stringent electromagnetic interference requirements which are expected on some Small Explorer Missions. The Power Systems Electronics (PSE) performs battery charge control using both temperature compensated charge/discharge ratio ampere hour integration and voltage-temperature control. The PSE includes all the circuits needed to perform telemetry and command functions using an optical MIL-STD-1773 interface.

Dakermanji, G.; Carlsson, U.; Temkin, D.; Culver, H.; Rodriguez, G. E.; Ahmad, A.

1991-01-01

247

Electron cyclotron resonance ion source control system  

International Nuclear Information System (INIS)

The ECR Ion source control system is a computer based control system. Main components of the ECR ion source are microwave generation, plasma chamber, solenoid magnets and power supplies, extraction electrodes and power supplies, beam measuring device and vacuum system. All electronics devices have their built in microprocessor base electronic interface, which can be remotely accessed by serial or Ethernet link. Two Ethernet to four port serial converter are used to extend the serial port of the computer. Serial interface of all the devices are connected to the extended serial ports of the computer. A serial link of high voltage power supplies have provided optical isolation using serial to optical converter to overcome EMI and EMC problems. The software has been developed in house for remote operation of the ECR ion source. (author)

248

Application of refrigeration system in electronics cooling  

International Nuclear Information System (INIS)

An experimental investigation of the transient response of the vapor compression refrigeration (VCR) system to rapid change in evaporator (simulated electronics) heat load is presented. In this study, the VCR system is designed and constructed specifically for applications to cool high heat flux electronics and high-end computers. Temperature and pressure data were measured at pre-selected locations to study the behavior of the refrigeration system to alterations in evaporator heat load. Results show that the VCR system maintains the junction temperature of the simulated electronics at a much lower temperature compared to conventional air-cooling systems. The maximum temperature was registered near the exit of the evaporator cold plate. Experimental evidence shows an oscillation in temperature with time at the evaporator cold plate and the thermostatic expansion valve prior to attaining steady-state condition, and that the thermostatic expansion valve and the evaporator time constants are equal; and have a value of 70 s. Also, for analytical and numerical models of heat transfer in evaporator cold plate, results shows that the assumption of one-dimensional temperature distribution is unrealistic

249

The electronic structure of condensed molecular systems  

Energy Technology Data Exchange (ETDEWEB)

We have reviewed some of the basic properties of the electronic structure of condensed molecular systems. For the rare-gas solids, we concentrated our discussion on changes in the ground- and excited-state crystal-atomic wave functions as calculated with an approximate theoretical method. Compression of these wave functions leads to a softening of the equation of state at high densities, which seems to account for much of the total many-body effects. This compression is a true many-body effect and cannot be easily decomposable into a sum of 3-body and higher terms. We reviewed the electronic properties of four molecular systems, each manifesting different behavior at high densities. Because of a general lack of theory of the electronic structure of molecular solids, we restricted ourselves to a descriptive account. Solid oxygen, for instance, seems to exhibit the beginnings of covalent bonding between the ..pi..* orbitals on adjacent molecules in its epsilon phase. It was a combination of optical-absorption data and infrared and Raman spectroscopy that led to these conclusions. Iodine is unique in that it becomes metallic as a molecular crystal at pressures easily obtainable experimentally. It is interesting that the x-ray data, which indicates a transition to a monatomic lattice at 21 GPa, and the Moessbauer spectra, which implies that molecular character is retained to 30 GPa, are in such disagreement. The next system discussed, solid acetylene, is a nice example of high-pressure polymerization and study of this system should shed light on the polymerization of more complicated systems. Finally, we briefly discussed the predicted dissociation of solid molecular nitrogen at high pressures. Here, theory has made a prediction and experiment has disproven it. Molecular systems show a diverse range of behavior in electronic structures at high pressures, from metallization to chemistry; theory is lagging. 68 refs., 10 figs.

LeSar, R.A.

1988-01-01

250

Freshwater aquaculture in the United States: Complying with environmental protection law and policy  

OpenAIRE

The author deal with the relations between the freshwater fish culture and the many regulations of the environmental protection in USA. The author develops the federal and state administrative frameworks (federal government administration of aquaculture, the state government administration of aquaculture), the freshwater aquaculture and water rights, the freshwater aquaculture and wetlands regulation, the freshwater aquaculture and water quality regulation, the freshwater aquaculture and wild...

Noble, M.

1993-01-01

251

Zope based electronic operation log system - Zlog  

International Nuclear Information System (INIS)

Since January 2004, the Zope based electronic operation logging system, named Zlog, has been running at the KEKB and AR accelerator facilities. Since Zope is the python based open source web application server software and python language is familiar for the members in the KEKB accelerator control group, we have developed the Zlog system rapidly. In this paper, we report the development history and the present status of Zlog system. Also we show some general plug-in components, called Zope products, have been useful for our Zlog development. (author)

252

Temperature measurement systems in wearable electronics  

Science.gov (United States)

The aim of this paper is to present the concept of temperature measurement system, adapted to wearable electronics applications. Temperature is one of the most commonly monitored factor in smart textiles, especially in sportswear, medical and rescue products. Depending on the application, measured temperature could be used as an initial value of alert, heating, lifesaving or analysis system. The concept of the temperature measurement multi-point system, which consists of flexible screen-printed resistive sensors, placed on the T-shirt connected with the central unit and the power supply is elaborated in the paper.

Walczak, S.; Go?ebiowski, J.

2014-08-01

253

Test software for BESIII MDC electronics system  

International Nuclear Information System (INIS)

This paper presents the design of Test System Software for BESIII MDC Electronics. Two kinds of test systems, SBS VP7 based and PowerPC based systems, and their corresponding test software are introduced. The software is developed in LabVIEW 7.1 and Microsoft Visual C++ 6.0, some test functions of the software, as well as their user interfaces, are described in detail. The software has been applied in hardware debugging, performance test and long term stability test. (authors)

254

Research about the electromagnetic interference of BES some electronics system  

International Nuclear Information System (INIS)

Authors introduces the influence of environmental temperature on the electromagnetic interference generated during the operation of BES some electronics system. Using EMC test system tests the conducted interference generated by BES shower counter electronics system. (authors)

255

Electronic Document Management Using Inverted Files System  

Directory of Open Access Journals (Sweden)

Full Text Available The amount of documents increases so fast. Those documents exist not only in a paper based but also in an electronic based. It can be seen from the data sample taken by the SpringerLink publisher in 2010, which showed an increase in the number of digital document collections from 2003 to mid of 2010. Then, how to manage them well becomes an important need. This paper describes a new method in managing documents called as inverted files system. Related with the electronic based document, the inverted files system will closely used in term of its usage to document so that it can be searched over the Internet using the Search Engine. It can improve document search mechanism and document save mechanism.

Suhartono Derwin

2014-03-01

256

Electronic Document Management Using Inverted Files System  

Science.gov (United States)

The amount of documents increases so fast. Those documents exist not only in a paper based but also in an electronic based. It can be seen from the data sample taken by the SpringerLink publisher in 2010, which showed an increase in the number of digital document collections from 2003 to mid of 2010. Then, how to manage them well becomes an important need. This paper describes a new method in managing documents called as inverted files system. Related with the electronic based document, the inverted files system will closely used in term of its usage to document so that it can be searched over the Internet using the Search Engine. It can improve document search mechanism and document save mechanism.

Suhartono, Derwin; Setiawan, Erwin; Irwanto, Djon

2014-03-01

257

Nonequilibrium quantum criticality in open electronic systems  

OpenAIRE

A theory is presented of quantum criticality in open (coupled to reservoirs) itinerant electron magnets, with nonequilibrium drive provided by current flow across the system. Both departures from equilibrium at conventional (equilibrium) quantum critical points and the physics of phase transitions induced by the nonequilibrium drive are treated. Nonequilibrium-induced phase transitions are found to have the same leading critical behavior as conventional thermal phase transit...

Mitra, Aditi; Takei, So; Kim, Yong Baek; Millis, A. J.

2006-01-01

258

Topology of bonding in ?-electron systems  

OpenAIRE

Delocalization in conjugated ?-electron systems is shown to be closely related to the topological concept of connectivity. A topological bond order is defined as a quantitative measure of the extent to which the subspace of a pair of adjacent atoms approximates a disconnected component of the molecular topological space. The agreement between this measure and molecular-orbital bond orders in the ordering of bond strengths within molecules is near perfect. There is also excellent quantitative...

Merrifield, R. E.; Simmons, H. E.

1985-01-01

259

Electronic circuits for communications systems: A compilation  

Science.gov (United States)

The compilation of electronic circuits for communications systems is divided into thirteen basic categories, each representing an area of circuit design and application. The compilation items are moderately complex and, as such, would appeal to the applications engineer. However, the rationale for the selection criteria was tailored so that the circuits would reflect fundamental design principles and applications, with an additional requirement for simplicity whenever possible.

1972-01-01

260

Electronic integrated disease surveillance system and pathogen asset control system.  

Science.gov (United States)

Electronic Integrated Disease Surveillance System (EIDSS) has been used to strengthen and support monitoring and prevention of dangerous diseases within One Health concept by integrating veterinary and human surveillance, passive and active approaches, case-based records including disease-specific clinical data based on standardised case definitions and aggregated data, laboratory data including sample tracking linked to each case and event with test results and epidemiological investigations. Information was collected and shared in secure way by different means: through the distributed nodes which are continuously synchronised amongst each other, through the web service, through the handheld devices. Electronic Integrated Disease Surveillance System provided near real time information flow that has been then disseminated to the appropriate organisations in a timely manner. It has been used for comprehensive analysis and visualisation capabilities including real time mapping of case events as these unfold enhancing decision making. Electronic Integrated Disease Surveillance System facilitated countries to comply with the IHR 2005 requirements through a data transfer module reporting diseases electronically to the World Health Organisation (WHO) data center as well as establish authorised data exchange with other electronic system using Open Architecture approach. Pathogen Asset Control System (PACS) has been used for accounting, management and control of biological agent stocks. Information on samples and strains of any kind throughout their entire lifecycle has been tracked in a comprehensive and flexible solution PACS.Both systems have been used in a combination and individually. Electronic Integrated Disease Surveillance System and PACS are currently deployed in the Republics of Kazakhstan, Georgia and Azerbaijan as a part of the Cooperative Biological Engagement Program (CBEP) sponsored by the US Defense Threat Reduction Agency (DTRA). PMID:23327375

Wahl, Tom G; Burdakov, Aleksey V; Oukharov, Andrey O; Zhilokov, Azamat K

2012-01-01

261

Electronic Integrated Disease Surveillance System and Pathogen Asset Control System  

Scientific Electronic Library Online (English)

Full Text Available SciELO South Africa | Language: English Abstract in english Electronic Integrated Disease Surveillance System (EIDSS) has been used to strengthen and support monitoring and prevention of dangerous diseases within One Health concept by integrating veterinary and human surveillance, passive and active approaches, case-based records including disease-specific c [...] linical data based on standardised case definitions and aggregated data, laboratory data including sample tracking linked to each case and event with test results and epidemiological investigations. Information was collected and shared in secure way by different means: through the distributed nodes which are continuously synchronised amongst each other, through the web service, through the handheld devices. Electronic Integrated Disease Surveillance System provided near real time information flow that has been then disseminated to the appropriate organisations in a timely manner. It has been used for comprehensive analysis and visualisation capabilities including real time mapping of case events as these unfold enhancing decision making. Electronic Integrated Disease Surveillance System facilitated countries to comply with the IHR 2005 requirements through a data transfer module reporting diseases electronically to the World Health Organisation (WHO) data center as well as establish authorised data exchange with other electronic system using Open Architecture approach. Pathogen Asset Control System (PACS) has been used for accounting, management and control of biological agent stocks. Information on samples and strains of any kind throughout their entire lifecycle has been tracked in a comprehensive and flexible solution PACS. Both systems have been used in a combination and individually. Electronic Integrated Disease Surveillance System and PACS are currently deployed in the Republics of Kazakhstan, Georgia and Azerbaijan as a part of the Cooperative Biological Engagement Program (CBEP) sponsored by the US Defense Threat Reduction Agency (DTRA).

Tom G., Wahl; Aleksey V., Burdakov; Andrey O., Oukharov; Azamat K., Zhilokov.

262

Electronic document management systems: an overview.  

Science.gov (United States)

For over a decade, most health care information technology (IT) professionals erroneously learned that document imaging, which is one of the many component technologies of an electronic document management system (EDMS), is the only technology of an EDMS. In addition, many health care IT professionals erroneously believed that EDMSs have either a limited role or no place in IT environments. As a result, most health care IT professionals do not understand documents and unstructured data and their value as structured data partners in most aspects of transaction and information processing systems. PMID:12402630

Kohn, Deborah

2002-08-01

263

Gas supply system for the ''Electron'' installation  

International Nuclear Information System (INIS)

The investigation results are described on a system for purifying and controlling the working gas of a helium streamer chamber operating on a bean of a electron linear accelerator. Maximum pressure in the system is 2 atm, and productivity at continuous helium circulation is 0.2 m2/hr. A chromatograph is used for determining the qualitative and quantitative composition of the gas. A gas-discharge cell is used for remote continuous control. Under operating conditions, the air impurity in the streamer chamber does not exceed 0.05%

264

The effects of aquaculture production noise on the growth, condition factor, feed conversion, and survival of rainbow trout, Oncorhynchus mykiss  

Science.gov (United States)

Intensive aquaculture systems, particularly recirculating systems, utilize equipment such as aerators, air and water pumps, blowers, and filtration systems that inadvertently increase noise levels in fish culture tanks. Sound levels and frequencies measured within intensive aquaculture systems are within the range of fish hearing, but species-specific effects of aquaculture production noise are not well defined. Field and laboratory studies have shown that fish behavior and physiology can be negatively impacted by intense sound. Therefore, chronic exposure to aquaculture production noise could cause increased stress, reduced growth rates and feed conversion efficiency, and decreased survival. The objective of this study was to provide an in-depth evaluation of the long term effects of aquaculture production noise on the growth, condition factor, feed conversion efficiency, and survival of cultured rainbow trout, Oncorhynchus mykiss. Rainbow trout were cultured in replicated tanks using two sound treatments: 117??dB re 1????Pa RMS which represented sound levels lower than those recorded in an intensive recycle system and 149??dB re 1????Pa RMS, representing sound levels near the upper limits known to occur in recycle systems. To begin the study mean fish weights in the 117 and 149??dB tanks were 40 and 39??g, respectively. After five months of exposure no significant differences were identified between treatments for mean weight, length, specific growth rates, condition factor, feed conversion, or survival (n = 4). Mean final weights for the 117 and 149??dB treatments were 641 ?? 3 and 631 ?? 10??g, respectively. Overall specific growth rates were equal, i.e. 1.84 ?? 0.00 and 1.84 ?? 0.01%/day. Analysis of growth rates of individually tagged rainbow trout indicated that fish from the 149??dB tanks grew slower during the first month of noise exposure (p growth and survival are unlikely to be affected over the long term by noise levels common to intensive aquaculture systems. ?? 2008 Elsevier B.V.

Davidson, J.; Bebak, J.; Mazik, P.

2009-01-01

265

Perception of Aquaculture Education to Support Further Growth of Aquaculture Industry in Victoria, Australia  

Science.gov (United States)

Purpose: The central aim of this study was to determine the perception of aquaculture educational provisions in the state of Victoria, and whether they are sufficient to ultimately support further growth of the industry. Design/methodology/approach: Questionnaires were formulated and distributed to participants in a variety of ways, including via…

Awal, Sadiqul; Christie, Andrew; Watson, Matthew; Hannadige, Asanka G. T.

2012-01-01

266

Capturing ecosystem services, stakeholders' preferences and trade-offs in coastal aquaculture decisions: a Bayesian belief network application.  

Science.gov (United States)

Aquaculture activities are embedded in complex social-ecological systems. However, aquaculture development decisions have tended to be driven by revenue generation, failing to account for interactions with the environment and the full value of the benefits derived from services provided by local ecosystems. Trade-offs resulting from changes in ecosystem services provision and associated impacts on livelihoods are also often overlooked. This paper proposes an innovative application of Bayesian belief networks - influence diagrams - as a decision support system for mediating trade-offs arising from the development of shrimp aquaculture in Thailand. Senior experts were consulted (n?=?12) and primary farm data on the economics of shrimp farming (n?=?20) were collected alongside secondary information on ecosystem services, in order to construct and populate the network. Trade-offs were quantitatively assessed through the generation of a probabilistic impact matrix. This matrix captures nonlinearity and uncertainty and describes the relative performance and impacts of shrimp farming management scenarios on local livelihoods. It also incorporates export revenues and provision and value of ecosystem services such as coastal protection and biodiversity. This research shows that Bayesian belief modeling can support complex decision-making on pathways for sustainable coastal aquaculture development and thus contributes to the debate on the role of aquaculture in social-ecological resilience and economic development. PMID:24155876

Schmitt, Laetitia Helene Marie; Brugere, Cecile

2013-01-01

267

Application of Medicinal Herbs to Aquaculture in Asia  

Directory of Open Access Journals (Sweden)

Full Text Available Aquaculture has increased greatly in Asia, but there are various problems associated with acquacultural production one of which is the use of antimicrobial agents resulting in more resistant bacterial strains which adversely affect human health and the natural environment. This paper presents information on the role and application of herbs for aquaculture in Asia.

Sataporn DIREKBUSARAKOM

2004-01-01

268

76 FR 9209 - Draft NOAA National Aquaculture Policy  

Science.gov (United States)

...the development of all forms of marine aquaculture, from shellfish farming...habitat restoration to the culture of marine fish and algae on land and offshore. The policy...affirms that sustainable U.S. marine aquaculture is vital to the...

2011-02-16

269

Research Progress in Biological Package for Aquaculture Wastewater Treatment  

Directory of Open Access Journals (Sweden)

Full Text Available The classification of biological package was reviewed in the present paper, and the application status of variousfillers for aquaculture wastewater treatment was introduced in detail. The developing direction of biologicalpackage in the field of aquaculture wastewater treatment was also presented.

Xi-dong MU

2010-05-01

270

Electronic journal management systems experiences from the field  

CERN Document Server

Discover how to manage your library's electronic journals?with tips from those who've already met the challenge!The explosive growth of electronic journals presents unique challenges for libraries. Electronic Journal Management Systems: Experiences from the Field comprehensively examines these complex topics, including explanations of the automated systems libraries have developed or adopted, licensing issues, and the provision of access to electronic journals. Respected library professionals discuss their own experiences in the implementation and use of electronic journal management systems,

Ives, Gary W

2013-01-01

271

Mechanisms of antimicrobial resistance in finfish aquaculture environments  

Directory of Open Access Journals (Sweden)

Full Text Available Consumer demand for affordable fish drives the ever-growing global aquaculture industry. The intensification and expansion of culture conditions in the production of several finfish species has been coupled with an increase in bacterial fish disease and the need for treatment with antimicrobials. Understanding the molecular mechanisms of antimicrobial resistance prevalent in aquaculture environments is important to design effective disease treatment strategies, to prioritize the use and registration of antimicrobials for aquaculture use, and to assess and minimize potential risks to public health. In this brief article we provide an overview of the molecular mechanisms of antimicrobial resistance mechanisms in finfish aquaculture environments and highlight specific research that should provide the basis of sound, science-based policies for the use of antimicrobials in aquaculture.

PatriciaL.Keen

2013-08-01

272

Mechanisms of antimicrobial resistance in finfish aquaculture environments.  

Science.gov (United States)

Consumer demand for affordable fish drives the ever-growing global aquaculture industry. The intensification and expansion of culture conditions in the production of several finfish species has been coupled with an increase in bacterial fish disease and the need for treatment with antimicrobials. Understanding the molecular mechanisms of antimicrobial resistance prevalent in aquaculture environments is important to design effective disease treatment strategies, to prioritize the use and registration of antimicrobials for aquaculture use, and to assess and minimize potential risks to public health. In this brief article we provide an overview of the molecular mechanisms of antimicrobial resistance in genes found in finfish aquaculture environments and highlight specific research that should provide the basis of sound, science-based policies for the use of antimicrobials in aquaculture. PMID:23986749

Miranda, Claudio D; Tello, Alfredo; Keen, Patricia L

2013-01-01

273

Synchronization system for electron linear accelerator  

International Nuclear Information System (INIS)

A system for synchronization of an electron linac providing reliable synchronous actuation of accelerator units at pulse frequency from single actuation to 1200 Hz, stabilization of mean current of an electron beam, automatic reduction of mean beam current when exceeding radiation safety standards, protection of clustron pulse amplifiers (CPa) in case of high-frequency breakdown, digital indication of CPa actuation frequency and pulse frequency is described. Rigid fixation of starting pulses to an arbitrary chosen phase of three-phase power line is reached with the application of frequency phase autotuning. Synchropulse delay during 0-20 ms (which corresponds to shift phase of 0-360 deg) with 20 ?s pitch and fine synchropulse delay tuning for separate accelerator units in the range of 0-35.6 ?s with 50 ns pitch is performed with digital lines of delay providing high time and temperature stabilities

274

SCOPE AND LIMITATION OF ELECTRONIC VOTING SYSTEM  

Directory of Open Access Journals (Sweden)

Full Text Available Electronic Voting are now being performed using World Wide Web in many countries of theworld due to this advancement a voter need not to visit the polling place. But has to just logging on thecomputer with an internet connection. Also, this voting requires an access code for the e-voting through theadvance report of a voter. To reduce these disadvantages, we suggest a process in which a voter, who has thewireless certificate issued in advance, uses its own mobile phone for an e-voting without the uniqueregistration for a vote. In this paper, a polling scheme by means of mobile technology is resented as mostfundamental application of GSM based Personal Response System, which allows a voter to cast his vote insimple and convenient way without the limit of time and location by integrating an electronic voting methodwith the GSM infrastructure.

Atiya Parveen

2013-05-01

275

Water Quality Monitoring and Control for Aquaculture Based on Wireless Sensor Networks  

OpenAIRE

We have designed and presented a wireless sensor network monitoring and control system for aquaculture. The system can detect and control water quality parameters of temperature, dissolved oxygen content, pH value, and water level in real-time. The sensor nodes collect the water quality parameters and transmit them to the base station host computer through ZigBee wireless communication standard. The host computer is used for data analysis, processing and presentation using LabVIEW software pl...

Simbeye, Daudi S.; Shi Feng Yang

2014-01-01

276

Antimicrobial resistance and antimicrobial resistance genes in marine bacteria from salmon aquaculture and non-aquaculture sites.  

Science.gov (United States)

Antimicrobial resistance (AR) detected by disc diffusion and antimicrobial resistance genes detected by DNA hybridization and polymerase chain reaction with amplicon sequencing were studied in 124 marine bacterial isolates from a Chilean salmon aquaculture site and 76 from a site without aquaculture 8 km distant. Resistance to one or more antimicrobials was present in 81% of the isolates regardless of site. Resistance to tetracycline was most commonly encoded by tetA and tetG; to trimethoprim, by dfrA1, dfrA5 and dfrA12; to sulfamethizole, by sul1 and sul2; to amoxicillin, by blaTEM ; and to streptomycin, by strA-strB. Integron integrase intl1 was detected in 14 sul1-positive isolates, associated with aad9 gene cassettes in two from the aquaculture site. intl2 Integrase was only detected in three dfrA1-positive isolates from the aquaculture site and was not associated with gene cassettes in any. Of nine isolates tested for conjugation, two from the aquaculture site transferred AR determinants to Escherichia coli. High levels of AR in marine sediments from aquaculture and non-aquaculture sites suggest that dispersion of the large amounts of antimicrobials used in Chilean salmon aquaculture has created selective pressure in areas of the marine environment far removed from the initial site of use of these agents. PMID:24612265

Shah, Syed Q A; Cabello, Felipe C; L'abée-Lund, Trine M; Tomova, Alexandra; Godfrey, Henry P; Buschmann, Alejandro H; Sørum, Henning

2014-05-01

277

The EH101 Electronic Instrument Systems  

Directory of Open Access Journals (Sweden)

Full Text Available This paper describes the background to the introduction of an electronic instrument system on the Anglo-Italian EH101 helicopter. The demanded flexibility to accommodate the display needs of several roles leading logically to the adoption of full colour multi-purpose display surfaces and the drive to achieve maximum commonality between military and civil variants is discussed. The configurations arrived at for both variants are described together with the operating philosophy and display formats developed during an ongoing simulator program. The paper also deals with a detailed description of the hardware implementation of the EIS including the fully integrated systems architecture and details of the symbol generators (SGs, display units (DUs and display mode selectors (DMSs. Emphasis is placed on the robust integrity characteristics and reversionary switching philosophy of the system."

Kieth N. Atkin

2013-04-01

278

Hy914, an electronic equipment test system  

International Nuclear Information System (INIS)

The article introduced the needs for thorough testing of electronic equipment with comparison between manual testing and automatic testing. An electronic equipment test system -HY914- which was used to test one network communication system was discussed in detail. HY914, which is able to do both black box testing and white box testing, is a integrated automatic test platform that provides rich features including test script, function testing, load testing, abnormal behaviour checking, application status monitoring, hardware resource monitoring and etc. HY914 also provides capability for doing complicated testing in short period and it helps to cut both labour cost and hours spent greatly. In between testing of the network communication system, engineers found and fixed a lot of software bugs such as device hanging, downgrading of voice quality and etc. By just doing minor changes of the test scripts, HY914 also provides the capability for users to test the device with minimum effort before a new software version is released. HY914 is designed to be used as a generic test platform and automatic testing of various products can be done by customising the test scripts, platform virtual machine, and virtual device driver. (authors)

279

Power Electronics in Wind Turbine Systems  

DEFF Research Database (Denmark)

The global electrical energy consumption is still rising and there is a steady demand to increase the power capacity. The production, distribution and the use of the energy should be as technological efficient as possible and incentives to save energy at the end-user should be set up. The deregulation of energy has lowered the investment in larger power plants, which means the need for new electrical power sources may be very high in the near future. Two major technologies will play important roles to solve the future problems. One is to change the electrical power production sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. The other is to use high efficient power electronics in power systems, power production and end-user application. This paper discuss the most emerging renewable energy source, wind energy, which by means of power electronics is changing from being a minor energy source to be acting as an important power source in the energy system. By that wind power is also getting an added value in the power system operation.

Blaabjerg, Frede; Chen, Zhe

2006-01-01

280

Electronic readout systems for microchannel plates  

International Nuclear Information System (INIS)

The microchannel plate (MCP) is an electron multiplier with a two-dimensional imaging capability. When coupled to a semi-transparent photocathode, the MCP forms a compact image intensifier which is widely used for night vision imaging applications. Alternatively, the MCP can be used in an open-structure configuration to detect high energy photons at extreme ultraviolet (EUV) and soft x-ray wavelengths or to directly detect charged particles. The recent development of MCPs which can be operated at high gain in the pulse-counting mode has made it possible to develop position-sensitive electronic systems which can directly detect the charge pulse from the MCP. These digital imaging systems have a large number of applications in astrophysics, plasma physics, and high-energy nuclear physics. The operating characteristics of the different systems which are currently in use or under development and their requirements on the performance characteristics of the high-gain MCPs are described in this paper

281

Structural dynamics of electronic and photonic systems  

CERN Document Server

The proposed book will offer comprehensive and versatile methodologies and recommendations on how to determine dynamic characteristics of typical micro- and opto-electronic structural elements (printed circuit boards, solder joints, heavy devices, etc.) and how to design a viable and reliable structure that would be able to withstand high-level dynamic loading. Particular attention will be given to portable devices and systems designed for operation in harsh environments (such as automotive, aerospace, military, etc.)  In-depth discussion from a mechanical engineer's viewpoint will be conducte

Suhir, Ephraim; Steinberg, David S

2011-01-01

282

Genomic approaches in marine biodiversity and aquaculture.  

Science.gov (United States)

Recent advances in genomic and post-genomic technologies have now established the new standard in medical and biotechnological research. The introduction of next-generation sequencing, NGS,has resulted in the generation of thousands of genomes from all domains of life, including the genomes of complex uncultured microbial communities revealed through metagenomics. Although the application of genomics to marine biodiversity remains poorly developed overall, some noteworthy progress has been made in recent years. The genomes of various model marine organisms have been published and a few more are underway. In addition, the recent large-scale analysis of marine microbes, along with transcriptomic and proteomic approaches to the study of teleost fishes, mollusks and crustaceans, to mention a few, has provided a better understanding of phenotypic variability and functional genomics. The past few years have also seen advances in applications relevant to marine aquaculture and fisheries. In this review we introduce several examples of recent discoveries and progress made towards engendering genomic resources aimed at enhancing our understanding of marine biodiversity and promoting the development of aquaculture. Finally, we discuss the need for auspicious science policies to address challenges confronting smaller nations in the appropriate oversight of this growing domain as they strive to guarantee food security and conservation of their natural resources. PMID:24510138

Huete-Pérez, Jorge A; Quezada, Fernando

2013-01-01

283

Genomic Approaches in Marine Biodiversity and Aquaculture  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: English Abstract in english Recent advances in genomic and post-genomic technologies have now established the new standard in medical and biotechnological research. The introduction of next-generation sequencing, NGS,has resulted in the generation of thousands of genomes from all domains of life, including the genomes of compl [...] ex uncultured microbial communities revealed through metagenomics. Although the application of genomics to marine biodiversity remains poorly developed overall, some noteworthy progress has been made in recent years. The genomes of various model marine organisms have been published and a few more are underway. In addition, the recent large-scale analysis of marine microbes, along with transcriptomic and proteomic approaches to the study of teleost fishes, mollusks and crustaceans, to mention a few, has provided a better understanding of phenotypic variability and functional genomics. The past few years have also seen advances in applications relevant to marine aquaculture and fisheries. In this review we introduce several examples of recent discoveries and progress made towards engendering genomic resources aimed at enhancing our understanding of marine biodiversity and promoting the development of aquaculture. Finally, we discuss the need for auspicious science policies to address challenges confronting smaller nations in the appropriate oversight of this growing domain as they strive to guarantee food security and conservation of their natural resources.

Jorge A, Huete-Pérez; Fernando, Quezada.

284

76 FR 43206 - Electronic Tariff Filing System (ETFS)  

Science.gov (United States)

...10-141; FCC 11-92] Electronic Tariff Filing System (ETFS...over the Internet, using the Electronic Tariff Filing System (ETFS...sought; (3) A showing of good cause; and (4) The appropriate...Washington, DC 20554.'' The Electronic Tariff Filing System...

2011-07-20

285

BPM System for Electron Cooling in the Fermilab Recycler Ring  

International Nuclear Information System (INIS)

We report a VXI based system used to acquire and process BPM data for the electron cooling system in the Fermilab Recycler ring. The BPM system supports acquisition of data from 19 BPM locations in five different sections of the electron cooling apparatus. Beam positions for both electrons and anti-protons can be detected simultaneously with a resolution of ±50 ?m. We calibrate the system independently for each beam type at each BPM location. We describe the system components, signal processing and modes of operation used in support of the electron-cooling project and present experimental results of system performance for the developmental electron cooling installation at Fermilab

286

Single Spin Measurement using Single Electron Transistors to Probe Two Electron Systems  

OpenAIRE

We present a method for measuring single spins embedded in a solid by probing two electron systems with a single electron transistor (SET). Restrictions imposed by the Pauli Principle on allowed two electron states mean that the spin state of such systems has a profound impact on the orbital states (positions) of the electrons, a parameter which SET's are extremely well suited to measure. We focus on a particular system capable of being fabricated with current technology: a ...

Kane, B. E.; Mcalpine, N. S.; Dzurak, A. S.; Clark, R. G.; Milburn, G. J.; Sun, He Bi; Wiseman, Howard

1999-01-01

287

Electron-beam evaporator for superhighvacuum systems  

International Nuclear Information System (INIS)

A small-size electron-beam evaporator with power of 1 kW for sputtering thin films of refractory metals in superhigh vacuum on vertical substrates is described. Main parts of the evaporator are the following: a cathode, shaping electrode, anode, copper unit, cooled with water and an evaporating sample placed on it in a small conical recess, which is previously flashed to make it approximately spherical. Such construction permits to reduce heat transfer from the sample to the water-cooled unit and to use an electron beam of low power for the evaporation. A compact electron gun with electron beam of about 3 mm diameter and power of 1 kW at an accelerating voltage up to 10 kV is developed for the evaporator. It consists of three electrodes arranged according to the Piers system, these electrodes are: tungsten foil cathode 20 mcm thick and 3.5 mm broad, shaping electrode with an opening 3.2 mm in diameter extruded of a tantalum foil and a copper anode. Evaporator performance testing have shown that when evaporating the refractory metals (Mo, W, Nb) the vacuum of an order of (2-7)x10-8 Pa is obtained. At that the maximum sputtering rate is reached at 0.5-1 kW power and constitutes about 20 A/s for Mo and W and 3-4 A/s for Nb when sputtering on substrates located at a distance of 100 mm from the sample

288

Effect of electron-electron interaction on thermal conductivity of disordered systems  

International Nuclear Information System (INIS)

Arfi presents a calculation of a correction to the thermal conductivity due to the inclusion of electron-electron interaction in a disordered metallic system. He finds that, to the first order in electron-electron interaction, the Wiedemann-Franz law is not satisfied

289

Nanomanipulation system for scanning electron microscope  

Science.gov (United States)

Traditionally scanning electron microscopy (SEM) is often used as a scientific instrument for providing high magnification images and analytical capability for microstructural analysis. In recent years different applications for SEM has been developed and is gaining popularity in doing characterizations of fine-scale materials such as in-situ annealing, cryo-microscopy, micro-tensile testing, electrical resistivity measurements and grain boundary/texture analysis (EBSD). With the increasing demand in these sub-micron to nano-scale characterizations, there's an increasing need to have a more sophisticated stage within the microscope. In other word, a stage that would have "hands" built onto the SEM stage to allow operator to manipulate objects and execute different tasks under high magnification. In this paper we presented a compact nanomanipulation system that is designed to be retrofitted easily onto many SEMs. Capabilities and potential applications of using such manipulation system will be discussed.

Woo, P.; Mekuz, I.; Chen, B.

2012-06-01

290

Broodstock management of the fine flounder Paralichthys adspersus (Steindachner, 1867) using recirculating aquaculture systems / Manejo de reproductores del lenguado Paralichthys adspersus (Steindachner, 1867) usando sistemas de recirculación en acuicultura  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: English Abstract in spanish El presente trabajo, describe la metodología desarrollada en IMARPE para la captura, aclimatación y acondicionamiento de ejemplares adultos de P. adspersus en sistemas de recirculación (SRA), con la finalidad de formar un stock de reproductores. El SRA permitió manejar parámetros medioambientales es [...] tables durante el periodo de acondicionamiento, como: temperatura del agua (17,2±1°C), oxígeno disuelto (8,1±0,7 mg L-1), pH (7,3±0,2), amonio (0,004±0,003 mg L-1), nitrito (0,52±0,2 mg L-1) y nitrato (3,45±2,6 mg L-1). Se dio inicio a la alimentación el día 15 post-captura, utilizando alimento vivo (Odonthestes regia regia, Mugil cephalus), crustáceos (Emerita analoga), alimento fresco (Engraulis ringens y Dosidicus gigas) y artificial semihúmedo. Durante los primeros días de acondicionamiento los peces mostraron una disminución en el peso, hasta su adaptación a las condiciones de cultivo, luego de lo cual se produjo un incremento continuo en ambos sexos. La tasa específica de crecimiento fue positiva a partir del tercer mes y la tasa de crecimiento relativo mostró que en agosto 2010, el peso promedio se incrementó 24,5% en machos y 16,2% en hembras. Se realizó un análisis patológico a los ejemplares capturados y se observó la presencia de diferentes parásitos internos y externos, entre ellos predominaron Entobdella sp. y Philometra sp. Abstract in english The present study describes the methodology used at IMARPE for the capture, acclimation and management of P. adspersus broodstock using recirculating aquaculture systems (RAS). RAS improved the water quality and maintained the environmental parameters during the acclimation period, temperature (17.2 [...] ±1°C), oxygen (8.1±0.7 mg L-1), pH (7.3±0.2), ammonia (0.004±0.003 mg L-1), nitrite (0.52±0.2 mg L-1) and nitrate (3.45±2.6 mg L-1). Fish began to be fed normally from day 15 post-capture, once or twice a day using live fish (Odonthestes regia regia, Mugil cephalus), crustacean (Emerita analoga), fresh food (Engraulis ringens and Dosidicus gigas) and artificial feed. A significant loss in the weight of the fish was registered during the first days of captivity, followed by a continuous increase in both sexes. The specific growth rate was positive from the third month of captivity, being the relative growth rate 24.5% and 16.2% in August 2010 in males and females, respectively. Different internal and external parasites were detected in the fish, being Entobdella sp. and Philometra sp. the prevailing parasites observed during samplings.

Lili, Carrera; Noemí, Cota; Melissa, Montes; Enrique, Mateo; Verónica, Sierralta; Teresa, Castro; Angel, Perea; Cristian, Santos; Christian, Catcoparco; Carlos, Espinoza.

2013-03-01

291

Key Performance Characteristics of Organic Shrimp Aquaculture in Southwest Bangladesh  

Directory of Open Access Journals (Sweden)

Full Text Available In Bangladesh, black tiger shrimp (Penaeus monodon; Fabricius, 1798 aquaculture has come to be one of the most important sectors in both the rural and national economies. Likewise, organic shrimp aquaculture has emerged as an alternative farming enterprise for farmers especially in the southwestern districts of Bangladesh. The present study aims to show key performance characteristics of organic shrimp farmers and farming in a prototypical shrimp farming area in Bangladesh. Data was collected in 2009 from organic shrimp farmers in the Kaligonj and Shyamnagar sub-districts through questionnaire interviews, transect walks and focus group discussions. The mean productivity of organic shrimp farming in the area is 320 kg ha?1 yr?1 (ranging from 120 to 711 kg ha?1year?1. Organic farmers are more likely to have a higher monthly income and less aquaculture experience. Moreover, suitable landholdings and classified labor distribution have been found to play an important role in the development of organic shrimp aquaculture. The most common assets of organic shrimp aquaculture are high yield, low production cost, available post larvae and high market prices. Small business farmers are likely to earn more income benefits from organic shrimp aquaculture than their larger-scale counterparts. Finally, the paper suggests that more research is needed to stimulate the success of organic shrimp aquaculture.

Christian Reinhard Vogl

2012-05-01

292

Engineering Automotive Electronic Systems: Decision Support for Successful Integration  

OpenAIRE

The electronic system of a modern vehicle is essential to achieve a successful automotive product. Vehicle development is performed by integrating components that include embedded electronics from several suppliers. This thesis present results on the subject of integration of automotive electronic systems. Our studies aim at providing knowledge on how to integrate automotive electronic systems successfully in a setting where vehicles are developed based on existing platforms. We focus on earl...

Fro?berg, Joakim

2007-01-01

293

Nonlinear Quantum Wave Equation of Radiation Electron and Dissipative Systems  

CERN Document Server

As well known, an electron will produce radiative reaction force when the electron emits electromagnetism radiation. The electron radiative effect had not been considered in Schr\\"{o}dinger wave equation. In this paper, we give the nonlinear quantum wave equations for the radiative electron and some dissipative systems.

Wu, Xiang-Yao; Zhang, Bai-Jun; Wu, Yi-Heng

2010-01-01

294

Parallel data acquisition system for electron momentum spectrometer  

CERN Document Server

A parallel data acquisition system has been developed for the study of electron impact ionization of atoms and molecules. The system has a large data storage capacity providing good experimental resolution and system flexibility. The system is used to collect and analyze data from electron momentum spectroscopy experiment. Results from electron momentum spectroscopy experiments on C sub 4 H sub 1 sub 0 molecules, at an incident energy of 1200 eV, are presented to demonstrate the performance of the system. (author)

Pang, W N

1999-01-01

295

Greening the Blue Revolution: How History Can Inform a Sustainable Aquaculture Movement  

OpenAIRE

This Paper traces the history of aquaculture from ancient China until the present, highlighting the various degrees of, and reasons for, aquaculture’s popularity at different points throughout history. The history of aquaculture demonstrates that the industry is largely a manifestation of concern over environmental and economic costs of the capture fishery industry; yet the current practice of aquaculture has begun to resemble the tortured past of wild-caught fish, with mono-culture fish f...

Smith, Turner

2014-01-01

296

THE FISHERIES AND AQUACULTURE COMPONENT OF RURAL DEVELOPMENT  

Directory of Open Access Journals (Sweden)

Full Text Available Fisheries and aquaculture can provide a key contribution to food security and poverty alleviation. Fisheries and aquaculture policy is an instrument for the conservation and management of fisheries and aquaculture. It was created with the aims of managing a common resource. Fisheries policies and management strategies the world over is in a state of flux, continued attempts to use fisheriesas the key to solving a complex web of social and economic issues threaten to overwhelm the basic fact that, if this resources are overfished, they will not sustain either social or development.

Adrian ZUGRAVU

2006-01-01

297

NMR study of strongly correlated electron systems  

International Nuclear Information System (INIS)

Various types of ground states in strongly correlated electron systems have been systematically investigated by means of NMR/NQR at low temperatures under high magnetic field and pressure. We focus on two well-known heavy-electron families, CeCu2X2 (X=Si and Ge) (Ce(122)) and UM2Al3 (M=Ni and Pd) (U(123)). The Cu NQR experiments on CeCu2X2 under high pressure indicate that the physical property of CeCu2Ge2 at high pressure, i.e. above the transition at 7.6GPa from antiferromagnetic (AF) to superconductivity, are clearly related to that of CeCu2Si2 at ambient pressure. In addition to the H-T phase diagram established below 7T, NMR and specific heat experiments on polycrystal CeCu2.05Si2 have revealed the presence of a new phase above 7T. In a high-quality polycrystal of UPd2Al3 with a record high-Tc of 2K at ambient pressure and the narrowest Al NQR line width, the nuclear-spin lattice relaxation rate, 27(1/T1) measured in zero field has been found to obey the T3 law down to 0.13K, giving strong evidence that the energy gap vanishes along lines on the Fermi surface. Thus it seems that all heavy-electron superconductors exhibit lines of zero gap, regardless of their different magnetic properties. ((orig.))

298

Ariadne: The Next Generation of Electronic Document Delivery Systems.  

Science.gov (United States)

Describes an approach to electronic document delivery which has evolved at Tilburg University (Netherlands), leading to the development of a system called Ariadne. Highlights include various generations of electronic document delivery systems; standards, including the work of the Group on Electronic Document Interchange; and a description of the…

Roes, Hans; Dijkstra, Joost

1994-01-01

299

75 FR 48629 - Electronic Tariff Filing System (ETFS)  

Science.gov (United States)

...10-141; FCC 10-127] Electronic Tariff Filing System (ETFS...the initiation of mandatory electronic filing. * * * * * 7. Section...sought; (3) A showing of good cause; and (4) The appropriate...Washington, DC 20554.'' The Electronic Tariff Filing System...

2010-08-11

300

Electron-optical systems for planar gyrotrons  

International Nuclear Information System (INIS)

The methodology of designing an electron-optical system (EOS) that forms sheet helical electron beams (HEBs) for high-power gyrotrons is developed. As an example, we consider the EOS for a 140-GHz gyrotron operated at the first harmonic of the cyclotron frequency with an accelerating voltage of 50?kV, a beam current of 30?A, and a magnetic field compression of 36. A planar geometry of the magnetron-injection gun (MIG) is suggested. The adiabatic theory of MIGs modified for the planar geometry of EOS is used for preliminary estimations of MIG parameters. Numerical simulation of the HEB properties based on the CST STUDIO SUITE 3D code is performed to find the optimal configuration of a planar MIG. The accuracy of the calculated data is discussed. The main factors that affect the HEB quality are considered. It is shown that a sheet HEB with a pitch-factor of 1.3 and velocity spread not exceeding 25%–30% can be formed; this is quite acceptable for high-efficiency operation of modern gyrotrons. Calculation of the beam-wave interaction with the obtained HEB parameters proved that a high output power with a sufficiently good efficiency of about 20% can be reached. Simulations show the feasibility of the experimental implementation of a novel planar EOS and its use in short-wave planar gyrotrons. The developed technique can be used for the study and optimization of planar gyrotrons of different frequency bands and power levels

301

Electron-optical systems for planar gyrotrons  

Science.gov (United States)

The methodology of designing an electron-optical system (EOS) that forms sheet helical electron beams (HEBs) for high-power gyrotrons is developed. As an example, we consider the EOS for a 140-GHz gyrotron operated at the first harmonic of the cyclotron frequency with an accelerating voltage of 50 kV, a beam current of 30 A, and a magnetic field compression of 36. A planar geometry of the magnetron-injection gun (MIG) is suggested. The adiabatic theory of MIGs modified for the planar geometry of EOS is used for preliminary estimations of MIG parameters. Numerical simulation of the HEB properties based on the CST STUDIO SUITE 3D code is performed to find the optimal configuration of a planar MIG. The accuracy of the calculated data is discussed. The main factors that affect the HEB quality are considered. It is shown that a sheet HEB with a pitch-factor of 1.3 and velocity spread not exceeding 25%-30% can be formed; this is quite acceptable for high-efficiency operation of modern gyrotrons. Calculation of the beam-wave interaction with the obtained HEB parameters proved that a high output power with a sufficiently good efficiency of about 20% can be reached. Simulations show the feasibility of the experimental implementation of a novel planar EOS and its use in short-wave planar gyrotrons. The developed technique can be used for the study and optimization of planar gyrotrons of different frequency bands and power levels.

Manuilov, V. N.; Zaslavsky, V. Yu.; Ginzburg, N. S.; Glyavin, M. Yu.; Kuftin, A. N.; Zotova, I. V.

2014-02-01

302

Power electronics for renewable energy systems  

DEFF Research Database (Denmark)

The global electrical energy consumption is still rising and there is a demand to double the power capacity within 20 years. The production, distribution and use of energy should be as technological efficient as possible and incentives to save energy at the end-user should also be set up. Deregulation of energy has in the past lowered the investment in larger power plants, which means the need for new electrical power sources may be very high in the near future. Two major technologies will play important roles to solve the future problems. One is to change the electrical power production sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. Another is to use high efficient power electronics in power generation, power transmission/distribution and end-user application. This paper discuss some of the most emerging renewable energy sources, wind energy and photovoltaics, which by means of power electronics are changing from being minor energy sources to be acting as important power sources in the energy system.

Iov, Florin; Blaabjerg, Frede

2009-01-01

303

Electron-optical systems for planar gyrotrons  

Energy Technology Data Exchange (ETDEWEB)

The methodology of designing an electron-optical system (EOS) that forms sheet helical electron beams (HEBs) for high-power gyrotrons is developed. As an example, we consider the EOS for a 140-GHz gyrotron operated at the first harmonic of the cyclotron frequency with an accelerating voltage of 50?kV, a beam current of 30?A, and a magnetic field compression of 36. A planar geometry of the magnetron-injection gun (MIG) is suggested. The adiabatic theory of MIGs modified for the planar geometry of EOS is used for preliminary estimations of MIG parameters. Numerical simulation of the HEB properties based on the CST STUDIO SUITE 3D code is performed to find the optimal configuration of a planar MIG. The accuracy of the calculated data is discussed. The main factors that affect the HEB quality are considered. It is shown that a sheet HEB with a pitch-factor of 1.3 and velocity spread not exceeding 25%–30% can be formed; this is quite acceptable for high-efficiency operation of modern gyrotrons. Calculation of the beam-wave interaction with the obtained HEB parameters proved that a high output power with a sufficiently good efficiency of about 20% can be reached. Simulations show the feasibility of the experimental implementation of a novel planar EOS and its use in short-wave planar gyrotrons. The developed technique can be used for the study and optimization of planar gyrotrons of different frequency bands and power levels.

Manuilov, V. N.; Zaslavsky, V. Yu.; Ginzburg, N. S.; Glyavin, M. Yu. [Institute of Applied Physics of the Russian Academy of Sciences, 46 Ul' yanov St., Nizhny Novgorod 603950 (Russian Federation); Nizhny Novgorod State University, 23 Gagarin Ave., Nizhny Novgorod 603950 (Russian Federation); Kuftin, A. N.; Zotova, I. V. [Institute of Applied Physics of the Russian Academy of Sciences, 46 Ul' yanov St., Nizhny Novgorod 603950 (Russian Federation)

2014-02-15

304

Performance of a constructed wetland treating intensive shrimp aquaculture wastewater under high hydraulic loading rate  

International Nuclear Information System (INIS)

A water treatment unit, mainly consisting of free water surface (FWS) and subsurface flow (SF) constructed wetland cells, was integrated into a commercial-scale recirculating aquaculture system for intensive shrimp culture. This study investigated performance of the treatment wetlands for controlling water quality. The results showed that the FWS-SF cells effectively removed total suspended solids (55-66%), 5-day biochemical oxygen demand (37-54%), total ammonia (64-66%) and nitrite (83-94%) from the recirculating water under high hydraulic loading rates (1.57-1.95 m/day). This led to a water quality that was suitable for shrimp culture and effluent that always satisfied the discharge standards. The area ratios of wetlands to culture tank being demonstrated (0.43) and calculated (0.096) in this study were both significantly lower than the reported values. Accordingly, a constructed wetland was technically and economically feasible for managing water quality of an intensive aquaculture system. - A constructed wetland was found to be technically and economically feasible for managing water quality of an intensive recirculating aquaculture system

305

Survey and Alignment of the Fermilab Electron Cooling System  

International Nuclear Information System (INIS)

The goal of achieving the Tevatron luminosity of 3 x 1032 cm-2s-1 requires Electron Cooling in the Recycler Ring to provide an increased flux of antiprotons. The Fermilab Electron Cooling system has been designed to assist accumulation of antiprotons for the Tevatron collider operations. The installation along with the survey and alignment of the Electron Cooling system in the Recycler Ring were completed in November 2004. The Electron Cooling system was fully commissioned in May 2005 and the first cooling of antiprotons was achieved in July 2005. This paper discusses the alignment methodology employed to survey and align the Electron Cooling system

306

Survey and Alignment of the Fermilab Electron Cooling System  

Energy Technology Data Exchange (ETDEWEB)

The goal of achieving the Tevatron luminosity of 3 x 10{sup 32} cm{sup -2}s{sup -1} requires Electron Cooling in the Recycler Ring to provide an increased flux of antiprotons. The Fermilab Electron Cooling system has been designed to assist accumulation of antiprotons for the Tevatron collider operations. The installation along with the survey and alignment of the Electron Cooling system in the Recycler Ring were completed in November 2004. The Electron Cooling system was fully commissioned in May 2005 and the first cooling of antiprotons was achieved in July 2005. This paper discusses the alignment methodology employed to survey and align the Electron Cooling system.

Oshinowo, Babatunde O' Sheg; Leibfritz, Jerry

2006-09-01

307

Raft River aquaculture project. Final report  

Energy Technology Data Exchange (ETDEWEB)

The commercial potential for geothermal aquaculture was evaluated for 2 years at the Department of Energy's Raft River geothermal site in southcentral Idaho. Common carp '(Cyprinus carpio) and channel catfish (Ictalurus punctatus) were selected as culture species. Objectives of the study included investigation of: (1) growth rates; (2) nutrition trials; (3) histological and physiological parameters; (4) bioaccumulation of heavy metals; and (5) reproductive capacity. The second year project efforts were primarily studying the effects of geothermal water on the reproductive capacity of common carp by: (1) determining the effects of geothermal water on gonadal development of common carp; and (2) determining the effects of geothermal water on common carp embryogenesis.

Beleau, M.H.; Woiwode, J.G.

1980-07-01

308

CERN Sells its Electronic Document Handling System  

CERN Multimedia

The EDH team. Left to right: Derek Mathieson, Rotislav Titov, Per Gunnar Jonsson, Ivica Dobrovicova, James Purvis. Missing from the photo is Jurgen De Jonghe. In a 1 MCHF deal announced this week, the British company Transacsys bought the rights to CERN's Electronic Document Handling (EDH) system, which has revolutionised the Laboratory's administrative procedures over the last decade. Under the deal, CERN and Transacsys will collaborate on developing EDH over the coming 12 months. CERN will provide manpower and expertise and will retain the rights to use EDH, which will also be available freely to other particle physics laboratories. This development is an excellent example of the active technology transfer policy CERN is currently pursuing. The negotiations were carried out through a fruitful collaboration between AS and ETT Divisions, following the recommendations of the Technology Advisory Board, and with the help of SPL Division. EDH was born in 1991 when John Ferguson and Achille Petrilli of AS Divisi...

2001-01-01

309

Advanced Photonic and Electronic Systems WILGA 2010  

CERN Document Server

SPIE – PSP WILGA Symposium gathers two times a year in January and in May new adepts of advanced photonic and electronic systems. The event is oriented on components and applications. WILGA Symposium on Photonics and Web Engineering is well known on the web for its devotion to “young research” promotion under the eminent sponsorship of international engineering associations like SPIE and IEEE and their Poland Sections or Counterparts. WILGA is supported by the most important national professional organizations like KEiT PAN and PSP-Photonics Society of Poland. The Symposium is organized since 1998 twice a year. It has gathered over 4000 young researchers and published over 2000 papers mainly internationally, including more than 900 in 10 published so far volumes of Proc. SPIE. This paper is a digest of WILGA Symposium Series and WILGA 2010 summary. Introductory part treats WILGA Photonics Applications characteristics over the period 1998-2010. Following part presents a short report on the XXVth and XXVI...

Romaniuk, R S

2010-01-01

310

The ALTA cosmic ray experiment electronics system  

International Nuclear Information System (INIS)

Understanding the origin and propagation of high-energy cosmic rays is a fundamental area of astroparticle physics with major unanswered questions. The study of cosmic rays with energy more than 1014 eV, probed only by ground-based experiments, has been restricted by the low particle flux. The Alberta Large-area Time-coincidence Array (ALTA) uses a sparse array of cosmic ray detection stations located in high schools across a large geographical area to search for non-random high-energy cosmic ray phenomena. Custom-built ALTA electronics is based on a modular board design. Its function is to control the detectors at each ALTA site allowing precise measurements of event timing and energy in the local detectors as well as time synchronization of all of the sites in the array using the global positioning system

311

RAD: a comprehensive software system for analytical electron microscopy  

International Nuclear Information System (INIS)

It is the purpose of this paper to describe a comprehensive software system called RAD designed to facilitate both electron diffraction analysis and x-ray EDS analysis in real-time on an analytical electron microscope

312

Aquaculture applications of a thermal effluent and considerations on geothermal water use  

Energy Technology Data Exchange (ETDEWEB)

Aquaculture may benefit from the use of thermal discharges from power plants or geothermal waters. Fish culture technology applicable to use of heated effluents should also apply generally to geothermal water sources. In the early 1970's the Tennessee Valley Authority and a private cooperator pumped thermal effluent from the discharge canal of the Gallatin Steam Plant near Nashville, TN, through a raceway facility, to evaluate an intensive culture system for catfish. Water tempertures averaged 5/sup 0/C above ambient plant intake water. Results demonstrated the potential of heated water to extend the growing season, enhance growth rates, and increase production. Numerous constraints hindering commercial use of thermal effluents for aquaculture were also identified.

Hubert, W.A.; Meriwether, J.

1977-11-16

313

Transmission Phase and Electron-Electron Interactions in Mesoscopic Systems  

International Nuclear Information System (INIS)

In a series of beautiful experiments by Yacobi, Schuster, Heiblum, Buksi Mahalu, Umansky and Shtrikman, the (relative) phase of an electron beam transmitted through a quantum dot has been measured. A high degree of correlation of this phase has been observed as consecutive transmission resonances through the dot were scanned (by varying a gate voltage). Notwithstanding a considerable theoretical effort, this result has not yet been accounted for. In particular, an independent electron picture cannot provide such correlations. We propose a model combining the effects of disorder and charging energy which results in generic phase correlations. We identify a large dimensionless parameter in tile theory which provides for such correlations. Possible experimental tests are proposed. The work has been supported by German-Israeli Foundation (GIF), by Israel Science Foundation founded by Israel Academy of Science and humanities- Centres of Excellence program, and by the Minerva foundation. Y.G. was an EPSRC fellow under grant GR/L67103

314

What Shapes Food Value Chains? : Lessons from Aquaculture in Asia  

DEFF Research Database (Denmark)

In this article, we explain what shapes food value chains through the analysis of selected aquaculture industries in four key Asian producing countries. Worldwide production of aquatic resources has grown rapidly in the past few decades, and aquaculture production in Asia has played a decisive role in this growth. We examine the main forms of coordination found along these value chains and the role that institutional frameworks play in governing them. We observe that negative publicity, driven by NGO and media campaigns, has led to increased use of third-party certification and the adoption of public and private standards. We find that the most sophisticated aquaculture operations in Asia are found in value chains led by retailers and branded processors and where the quality of domestic institutional frameworks has facilitated compliance with increasing demands from buyers overseas. Finally, we reflect on the sustainability challenges of aquaculture and provide four broad observations on the governance of food value chains.

Jespersen, Karen Sau; Kelling, Ingrid

2014-01-01

315

Salmon Aquaculture and Antimicrobial Resistance in the Marine Environment  

OpenAIRE

Antimicrobials used in salmon aquaculture pass into the marine environment. This could have negative impacts on marine environmental biodiversity, and on terrestrial animal and human health as a result of selection for bacteria containing antimicrobial resistance genes. We therefore measured the numbers of culturable bacteria and antimicrobial-resistant bacteria in marine sediments in the Calbuco Archipelago, Chile, over 12-month period at a salmon aquaculture site approximately 20 m from a s...

Buschmann, Alejandro H.; Tomova, Alexandra; Lo?pez, Alejandra; Maldonado, Miguel A.; Henri?quez, Luis A.; Ivanova, Larisa; Moy, Fred; Godfrey, Henry P.; Cabello, Felipe C.

2012-01-01

316

Mechanisms of antimicrobial resistance in finfish aquaculture environments  

OpenAIRE

Consumer demand for affordable fish drives the ever-growing global aquaculture industry. The intensification and expansion of culture conditions in the production of several finfish species has been coupled with an increase in bacterial fish disease and the need for treatment with antimicrobials. Understanding the molecular mechanisms of antimicrobial resistance prevalent in aquaculture environments is important to design effective disease treatment strategies, to prioritize the use and regis...

PatriciaL.Keen; ClaudioD.Miranda; AlfredoTello

2013-01-01

317

The role of microalgae in aquaculture: situation and trends  

OpenAIRE

Algae are utilized diversely in aquaculture, but their main applications are related to nutrition. They are used in toto, as a sole component or as a food additive to supply basic nutrients, color the flesh of salmonids or for other biological activities. The need for nutritional sources safer than traditional animal products has renewed interest in plants in general and algae in particular. This report deals principally with the nutritional role of microalgae in aquaculture.The larvae of mol...

Muller-feuga, Arnaud

2000-01-01

318

Development of a GIS-Based Tool for Aquaculture Siting  

OpenAIRE

Nearshore aquaculture siting requires the integration of a range of physical, environmental, and social factors. As a result, the information demand often presents coastal managers with a range of complex issues regarding where specific types of aquaculture should be ideally located that reduce environmental and social impacts. Here we provide a framework and tool for managers faced with these issues that incorporate physical and biological parameters along with geospatial infrastructure. In ...

Noelani Puniwai; Lisa Canale; Maria Haws; James Potemra; Christopher Lepczyk; Steven Gray

2014-01-01

319

Key Performance Characteristics of Organic Shrimp Aquaculture in Southwest Bangladesh  

OpenAIRE

In Bangladesh, black tiger shrimp (Penaeus monodon; Fabricius, 1798) aquaculture has come to be one of the most important sectors in both the rural and national economies. Likewise, organic shrimp aquaculture has emerged as an alternative farming enterprise for farmers especially in the southwestern districts of Bangladesh. The present study aims to show key performance characteristics of organic shrimp farmers and farming in a prototypical shrimp farming area in Banglade...

Christian Reinhard Vogl; Brojo Gopal Paul

2012-01-01

320

Power electronic converter systems for direct drive renewable energy applications  

DEFF Research Database (Denmark)

This chapter presents power electronic conversion systems for wind and marine energy generation applications, in particular, direct drive generator energy conversion systems. Various topologies are presented and system design optimization and reliability are briefly discussed.

Chen, Zhe

2013-01-01

321

One nanosecond pulsed electron gun systems  

International Nuclear Information System (INIS)

At SLAC there has been a continuous need for the injection of very short bunches of electrons into the accelerator. Several time-of-flight experiments have used bursts of short pulses during a normal 1.6 micro-second rf acceleration period. Single bunch beam loading experiments made use of a short pulse injection system which included high power transverse beam chopping equipment. Until the equipment described in this paper came on line, the basic grid-controlled gun pulse was limited to a rise time of 7 nanoseconds and a pulse width of 10 nanoseconds. The system described here has a grid-controlled rise time of less than 500 pico-seconds, and a minimum pulse width of less than 1 nanosecond. Pulse burst repetition rate has been demonstrated above 20 MHz during a 1.6 microsecond rf accelerating period. The order-of-magnitude increase in gun grid switching speed comes from a new gun design which minimizes lead inductance and stray capacitance, and also increases gun grid transconductance. These gun improvements coupled with a newly designed fast pulser mounted directly within the gun envelope make possible subnanosecond pulsing of the gun

322

Performance of Nile tilapia Oreochromis niloticus fingerlings in a hyper-intensive recirculating aquaculture system with low water exchange / Rendimiento de juveniles de tilapia del Nilo Oreochromis niloticus en un sistema híperintensivo de recirculación acuícola con mínimo recambio de agua  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: English Abstract in spanish El objetivo de este trabajo fue evaluar el rendimiento de juveniles de tilapia del Nilo Oreochromis niloticus sembrados en densidades hiperintensivas en un sistema de recirculación acuícola (SRA) con mínimo remplazo de agua. El sistema experimental consistió en un sistema de precría de cosecha única [...] para obtener peces de 50 g en 60 días. Los peces (2,07 ± 0,14 g) se sembraron por triplicado a densidades de 400 (T1), 500 (T2) y 600 (T3) peces m-3 (0,84; 1,05; 1,22 kg m-3). El SRA funcionó con 12.000 L de agua recirculante y un remplazo diario de 252 L (2,1% por día). La densidad de siembra no afectó significativamente la supervivencia (89,5-93,6%). El biofiltro removió el amonio nitrogenado total con una eficiencia del 46,9 ± 7,0%. La tasa de crecimiento de T1 (0,96 g día-1; 5,01% día-1) y T2 (0,92 g día-1; 4,95% día-1) fue significativamente mayor que T3 (0,83 g día-1; 4,80% día-1). La temperatura influyó 41% en la tasa de crecimiento específico (TCE) de T1. La concentración de oxígeno disuelto (DO) influyó en la variación de peso en T2 (47%) y T3 (44%). La TCE de T3 también se vio afectada por la concentración de nitrógeno amoniacal (31%). El aumento de la densidad de siembra afectó el tamaño y la homogeneidad de tallas de los peces, pero no afectó la relación longitud-peso (L-P). Los datos respaldan la conclusión que los juveniles sembrados a densidades de 400 y 500 peces m-3 tienen alto rendimiento durante nueve semanas consecutivas, siempre y cuando la biomasa no se exceda de 37 kg m-3. En este tiempo los peces alcanzan el peso final esperado de precría (50 g) y pueden ser transferidos hacia las instalaciones de engorde. Abstract in english The aim of this paper was evaluate the performance of Nile tilapia fingerlings (Oreochromis niloticus) raised at hyper intensive stocking density in a recirculating aquaculture system (RAS) with minimum water replacing. The experimental system was performed in a single-batch nursery system to obtain [...] 50 g fish size in 60 days. Fish (2.07 ± 0.04 g) were stocked in triplicate at 400 (T1), 500 (T2) and 600 (T3) fish m-3 (0.84, 1.05, 1.22 kg m-3). RAS functioned with 12,000 L of recirculating water and 252 L day-1of water replacing (2.1% daily). The efficiency of the biofilter for removing the total ammonia nitrogen (TAN) was 48 ± 12.5 mg L-1. Stocking density did not affect significantly the survival (89.5 to 93.6%). The growth rate of T1 (0.96 g day-1; 5.01% day-1) and T2 (0.92 g day-1; 4.95 % day-1) was significantly higher than T3 (0.83 g day-1; 4.80% day-1). The specific growth rate (SGR) of T1 was 41% influenced by temperature. For T2 and T3 the SGR were influenced by the variation of dissolved oxygen (DO) that explained 47 and 44% of the fish weight variation, respectively. The SGR from T3 was also affected by the concentration of ammonia nitrogen (31%). The high stocking density affected the overall size of fish and the size homogeneity, but had no negative effect on the length-weight relationship (L-W). Data support the conclusion that fingerling stocked at 400 and 500 fish m-3 shows high performance during 9-weeks when the biomass not exceed 37 kg m-3. At this time fish have reached the desired final nursery weight (50 g) for transfer to grow-out facilities.

M, Gullian-Klanian; C, Arámburu-Adame.

2013-03-01

323

Non-Contact Electron Optics System for Coincidence Imaging Analysis  

Science.gov (United States)

An electron imaging system has been developed for spatial information in coincidence Instrumental Neutron Activation Analysis. In our technique, a beta-radioactive sample is scanned at once where the electrons are detected in the position-sensitive Timepix detector in coincidence with ?-rays. Following our previous work where the detector was used in close-contact sample geometry, we have built a devoted non-contact electron optic system to focus coincidence electrons for imaging measurements with enhanced spatial resolution and reduced blurring. This contribution describes the electron focusing system and its evaluation.

Kroupa, Martin; Jakubek, Jan; Krejci, Frantisek

2010-04-01

324

Magnetic ordering in strongly correlated-electron uranium systems: Consequences of two kinds of f-electron-band-electron states  

Science.gov (United States)

Magnetic ordering involves the electronic behavior globally; and for uranium-based systems, the hybridization-induced effects dominate over the Coulomb exchange effects in determining the magnetic ordering. Therefore, as long as the hybridization is treated as acting between properly exchange-symmetrized two-electron wave functions, the effects of exchange can be incorporated in the one-electron exchange-correlation potential. As a consequence of the necessary exchange symmetrization, there are essentially two kinds of f electrons, localized magnetic and itinerant nonmagnetic. This has enabled us to make absolute material-specific predictions of alloying or high-pressure effects on magnetic ordering in uranium strongly correlated-electron (SCE) systems using local-density approximation input into many-electron dynamics. Experimentally, the alloying effects can be dramatic, e.g., in UxLa1-xS the magnetic ordering abruptly disappears at about 55% uranium. The theory is quite successful in its detailed absolute predictions, and this has important implications for the overall understanding of electronic behavior in SCE systems including heavy fermion systems. The key conclusion is that strengthening the hybridization, as kinematically restricted by exchange symmetry, leads to a chemical-environment-dependent sharp phase transition in SCE systems with dramatic observable consequences. This phase transition is associated with the elimination of the localized-magnetic transition-shell electrons (f electrons for light actinide and cerium-based SCE materials, d electrons for transition-metal-oxide-based SCE materials).

Cooper, Bernard R.; Lin, Yeong-Lieh; Sheng, Qing-Guang

1999-04-01

325

Operation of Doublet III electron cyclotron system  

International Nuclear Information System (INIS)

The first phase of operation of the Doublet III 60 GHz ECH system has been completed. In this phase, the power from two gyrotrons which put out a total of 340 kW for pulse lengths to 85 msec was used to launch the ordinary wave from the low field side of the plasma. The gyrotrons were Varian VGE-8060 tubes designed for 100 msec pulses; the gyrotrons which will be used for subsequent experimental phases at total power up to 2 MW are Varian VGE-8006 cw tubes, for pulse lengths up to 5 sec. (Pulse lengths are limited by the power supply.) The high voltage system used to power up to ten gyrotrons is shown. The power source is an 80 kV,.100 A power supply that was designed for neutral beam operation and which was modified for negative polarity as required for gyrotron operation. This power supply provided a single series modulator/regulator for the entire system, with individual gyrotron operation controlled by a low power switch tube (Thompson 5185) and compensated resistive voltage divider. The voltage divider determines the voltage on the gyrotron gun anode, which acts as a control grid for the gyrotron electron gun. The individual gyrotrons are isolated from each other by 100 ? series resisters. This approach to gyrotron control has proved to be effective in operation of at least two gyrotrons simultaneously; it is also highly cost-effective compared to providing a series modulator/regulator for each gyrotron. Cross-talk between gyrotrons either through the power suppn gyrotrons either through the power supply or through the waveguide has not been a problem

326

Duke Electronic Mail Post Office A Practical Mail Linking System*  

OpenAIRE

This paper describes a system designed to integrate the many different electronic mail systems in use throughout Duke University. The Duke Electronic Mail Post Office project is part of Duke University Medical Center's model for Achieving an Integrated Academic Information Management System (IAIMS).

Dryfoos, James D.; Hammond, William E.; Spero, Laurence A.; Rabold, Jean S.; Straube, Mark J.; Stead, William W.

1988-01-01

327

Power electronics system integration for electric and hybrid vehicles  

OpenAIRE

The paper gives an overview of the basic requiremensts, concepts, and trends regarding a system intergration of power electronics in hybrid (HEV) an electric vehicles (EV). A site-of-action system integration of the various power electronics subsystems minimizes costs and construction space requirements. New technologies that foster a system integration of power electronics and a merging with the mechanical environment are presented. The focus is on power modules and passive components.

Ma?rz, M.; Schletz, A.; Eckardt, B.; Engelkraut, S.; Rauh, H.

2010-01-01

328

Establishment of a mobile electron beam treatment system  

International Nuclear Information System (INIS)

The main goal of the project was the construction of mobile electron beam treatment system. The system of mobile electron beam was needed against the environmental problem that was not able to be figured out by the conventional treatment technologies. The mobile electron beam system was constructed for the field demonstration of treatment and remediation of various contaminated environments to obtain New Environmental Technology (NET) of Ministry of Environment (MOE)

329

NASA Electronic Library System (NELS): The system impact of security  

Science.gov (United States)

This paper discusses security issues as they relate to the NASA Electronic Library System which is currently in use as the repository system for AdaNET System Version 3 (ASV3) being operated by MountainNET, Inc. NELS was originally designed to provide for public, development, and secure collections and objects. The secure feature for collections and objects was deferred in the initial system for implementation at a later date. The NELS system is now 9 months old and many lessons have been learned about the use and maintenance of library systems. MountainNET has 9 months of experience in operating the system and gathering feedback from the ASV3 user community. The user community has expressed an interest in seeing security features implemented in the current system. The time has come to take another look at the whole issue of security for the NELS system. Two requirements involving security have been put forth by MountainNET for the ASV3 system. The first is to incorporate at the collection level a security scheme to allow restricted access to collections. This should be invisible to end users and be controlled by librarians. The second is to allow inclusion of applications which can be executed only by a controlled group of users; for example, an application which can be executed by librarians only. The requirements provide a broad framework in which to work. These requirements raise more questions than answers. To explore the impact of these requirements a top down approach will be used.

Mcgregor, Terry L.

1993-01-01

330

Spin, spin-orbit, and electron-electron interactions in mesoscopic systems  

OpenAIRE

We review recent theoretical developments about the role of spins, electron-electron interactions, and spin-orbit coupling in metal nanoparticles and semiconductor quantum dots. For a closed system, in the absence of spin-orbit coupling or of an external magnetic field, electron-electron interactions make it possible to have ground states with spin $S > 1/2$. We review here a theoretical analysis which makes predictions for the probability of finding various values of spin $...

Oreg, Yuval; Brouwer, P. W.; Waintal, X.; Halperin, Bertrand I.

2001-01-01

331

Nonlinear electron-acoustic rogue waves in electron-beam plasma system with non-thermal hot electrons  

Science.gov (United States)

The properties of nonlinear electron-acoustic rogue waves have been investigated in an unmagnetized collisionless four-component plasma system consisting of a cold electron fluid, non-thermal hot electrons obeying a non-thermal distribution, an electron beam and stationary ions. It is found that the basic set of fluid equations is reduced to a nonlinear Schrodinger equation. The dependence of rogue wave profiles on the electron beam and energetic population parameter are discussed. The results of the present investigation may be applicable in auroral zone plasma.

Elwakil, S. A.; El-hanbaly, A. M.; Elgarayh, A.; El-Shewy, E. K.; Kassem, A. I.

2014-11-01

332

Nonlinear electron-acoustic solitary waves in a relativistic electron-beam plasma system with non-thermal electrons  

International Nuclear Information System (INIS)

The nonlinear properties of small amplitude electron-acoustic solitary waves (EASWs) have been investigated in an unmagnetized collisionless four-component plasma system consisting of a cold relativistic electron fluid, non-thermal hot electrons obeying a non-thermal distribution, a relativistic electron beam and stationary ions. It is found that the basic set of fluid equations is reduced to a Korteweg-de Vries (KdV) equation, which governs the nonlinear characteristics of EASWs. The effects of relativistic electrons and energetic population parameter ? on the nature of EASWs are discussed

333

Tocopherols in Seafood and Aquaculture Products.  

Science.gov (United States)

ABSTRACT Fish products contain various nutritionally beneficial components, namely, ?3 polyunsaturated fatty acids (?3-PUFA), minerals, and vitamins. Particularly, tocopherols (?-, ?-, ?-, and ?-tocopherol) can be provided by seafood and aquaculture products. Hence, this review shows the various aspects of tocopherols in seafood and aquaculture products. For tocopherol determination in these products, HPLC methods coupled with diode array detection in the UV area of the spectrum or fluorescence detection have been shown as sensitive and accurate. These newest methods have helped in understanding tocopherols fate upon ingestion by seafood organisms. Tocopherols pass through the intestinal mucosa mainly by the same passive diffusion mechanism as fats. After absorption, the transport mechanism is thought to consist of two loops. The first loop is dietary, including chylomicrons and fatty acids bound to carrier protein, transporting lipids mainly to the liver. The other is the transport from the liver to tissues and storage sites. Moreover, tocopherol levels in fish organisms correlate with diet levels, being adjusted in fish body depending on diet concentration. For farmed fish species, insufficient levels of tocopherols in the diet can lead to poor growth performance or to nutritional disease. The tocopherol quantity needed as a feed supplement depends on various factors, such as the vitamer mixture, the lipid level and source, the method of diet preparation, and the feed storage conditions. Other ingredients in diet may be of great importance, it has been proposed that ?-tocopherol may behave as a prooxidant synergist at higher concentrations when prooxidants such as transition metals are present. However, the antioxidant action of tocopherols outweighs this prooxidant effect, provided that adequate conditions are used. In fact, muscle-based foods containing higher levels of tocopherol show, for instance, higher lipid stability. Besides, tocopherols are important not only from the nutritional point of view but also from the physiological one, since they are involved in many metabolic processes in the human organism. Moreover, synergistic interactions with selenium and ascorbic acid have been reported. It deserves attention that there is evidence tocopherols taken with food can prevent heart disease, while no such evidence was found for ?-tocopherol as supplement. From this perspective, eating fish is advisable, since, for instance, a 100 g serving of salmon may provide nearly 14 % of recommended dietary allowance. PMID:24915325

Afonso, Cláudia; Bandarra, Narcisa M; Nunes, Leonor; Cardoso, Carlos

2013-10-11

334

Consumer behaviour and preferences for aquaculture products  

DEFF Research Database (Denmark)

During the last decades, the proportion of aquaculture products in the market place has increased dramatically and this trend seems to continue in the future as well. While both the producers of aquaculture products as well as the distribution channels are aware of this change in product composition, still little is known about the effect this has on consumer preferences and product choices. In connection with the SEAFOODplus project CONSUMERSURVEY, which aims at explaining seafood consumption, a major survey has been carried out in five European countries in order to achieve more knowledge about consumer preferences and choice in relation to fish in general as well as preferences for farmed and wild fish. Questionnaires were sent to a representative sample of consumers in 5 European countries: Denmark, Belgium, Netherlands, Poland and Spain, and a total of 4786 valid questionnaires were returned and analysed. Results show that there is widespread confusion regarding whether fish is wild or farmed. The data disclose large discrepancies in reported total fish consumption frequency as shown in Table 1 and reported consumption of wild and farmed fish as shown in table 2. From the total sample, 2.5% claim to never or seldom eat fish in general. About one third claim never to eat farmed fish, and also one third claims never to eat wild fish. Combining these, it turns out that 24.8% of the total sample claim neither to eat farmed nor wild fish. It seems, however, that the confusion about wild and farmed fish increases with age, since the reported consumption of wild fish decreases with increasing age, which is the opposite trend compared to reported overall fish consumption. The data shows that on average the consumption of fish increases with increasing age in all countries except Poland where differences in consumption frequencies were not significant across age groups. On average fresh wild fish is perceived to be of higher quality compared to farmed fish. On the other hand, fresh farmed fish is perceived to have a more consistent quality compared to fresh wild fish and to be more available and thus easier to purchase. Furthermore, when it comes to safety, consumers do not perceive any difference in relation to the safety of fresh wild fish and fresh farmed fish.

BrunsØ, Karen; Scholderer, Joachim

335

Diagnostic Neural Network Systems for the Electronic Circuits  

International Nuclear Information System (INIS)

Neural Networks is one of the most important artificial intelligent approaches for solving the diagnostic processes. This research concerns with uses the neural networks for diagnosis of the electronic circuits. Modern electronic systems contain both the analog and digital circuits. But, diagnosis of the analog circuits suffers from great complexity due to their nonlinearity. To overcome this problem, the proposed system introduces a diagnostic system that uses the neural network to diagnose both the digital and analog circuits. So, it can face the new requirements for the modern electronic systems. A fault dictionary method was implemented in the system. Experimental results are presented on three electronic systems. They are: artificial kidney, wireless network and personal computer systems. The proposed system has improved the performance of the diagnostic systems when applied for these practical cases

336

Electron scattering and few-nucleon systems  

International Nuclear Information System (INIS)

In these lectures, is discussed a selection of recent electron scattering data which illustrate some of the recent developments of this field. The last five years have seen the emergence of a new generation of electron scattering experiments. These data have clearly shown the limits of the traditional description of nuclear physics

337

A Layman's Guide to Geothermal Aquaculture  

Energy Technology Data Exchange (ETDEWEB)

The following paper is designed as an aid to anyone contemplating a venture into commercially raising giant freshwater prawns, Macrobrachium rosenbergii. Oregon Institute of Technology has been actively involved in a research program to determine the feasibility of such a venture and results to date have been very encouraging. This aquaculture research was initiated in 1975 and was developed as an effort to utilize excess energy from the school’s geothermal heating system. Therefore, most of the information gathered here, will apply to flow-through systems which use geothermal water to maintain a suitable environment for the animals. A study of the market potential for freshwater prawns has been conducted and a favorable response received from wholesale distributors in the Pacific Northwest. Not only is a good market available, but distributors have suggested paying from $4.50 to $5.00 per pound for whole prawns in the size category of 16 to 20 tails to the pound, for a constant fresh supply. By maintaining constant temperatures of 27 degrees Celsius (80 degrees Fahrenheit) ± 1 degree Celsius in our research ponds, we have been able to produce this size prawn in 6 to 8 months.

Smith, Kenan C.

1981-01-01

338

Electronic systems failures and anomalies attributed to electromagnetic interference  

Science.gov (United States)

The effects of electromagnetic interference can be very detrimental to electronic systems utilized in space missions. Assuring that subsystems and systems are electrically compatible is an important engineering function necessary to assure mission success. This reference publication will acquaint the reader with spacecraft electronic systems failures and anomalies caused by electromagnetic interference and will show the importance of electromagnetic compatibility activities in conjunction with space flight programs. It is also hoped that the report will illustrate that evolving electronic systems are increasingly sensitive to electromagnetic interference and that NASA personnel must continue to diligently pursue electromagnetic compatibility on space flight systems.

Leach, R. D. (editor); Alexander, M. B. (editor)

1995-01-01

339

Web Content Processing Method for Electronic Business Systems  

Directory of Open Access Journals (Sweden)

Full Text Available The given article is devoted to the development of standardized methods and software Web content processing in e-business systems. The model of electronic content commerce systems is developed. The models of commercial Web content processing subsystems are constructed. A new approach of business processes application and implementation for the construction of electronic content commerce systems is formulated. Complex methods of formation, management and support commercial content are developed. Software for information resources processing in electronic content commerce systems is developed. The methods of e-business systems designing and implementation are presented as example on online newspaper and online magazine that reflect the theoretical studies results.

Victoria Vysotska

2013-12-01

340

A control system for a free electron laser experiment  

International Nuclear Information System (INIS)

The general layout of a control and data acquisition system for a Free Electron Laser experiment will be discussed. Some general considerations about the requirements and the architecture of the whole system will be developed. (author)

341

Integrated measurement systems for electronic devices operating in radiation environment  

International Nuclear Information System (INIS)

Electronic systems in High Energy Physics experiments are exposed to radiation. Such hard environment provokes damages and errors in electronic devices. This M.Sc. thesis describes the radiation effects on different types of electronic components. Three measurement systems are presented, for irradiation experiments on Light Emitting Diodes, semiconductor memories (SDRAM and FLASH) and FPGA chips. Results of several tests that have been done are included and discussed. (orig.)

342

Electronic Liquid Crystal Phases in Strongly Correlated Systems  

OpenAIRE

In this lectures I discuss the electronic liquid crystal (ELC) phases in correlated electronic systems, what these phases are and in what context they arise. I will go over the strongest experimental evidence for these phases in a variety of systems: the two-dimensional electron gas in magnetic fields, the bilayer material Sr$_3$Ru$_2$O$_7$ (also in magnetic fields), and a set of phenomena in the cuprate superconductors (and more recently in the pnictide materials) that can ...

Fradkin, Eduardo

2010-01-01

343

Multilayer electronic component systems and methods of manufacture  

Science.gov (United States)

Multilayer electronic component systems and methods of manufacture are provided. In this regard, an exemplary system comprises a first layer of liquid crystal polymer (LCP), first electronic components supported by the first layer, and a second layer of LCP. The first layer is attached to the second layer by thermal bonds. Additionally, at least a portion of the first electronic components are located between the first layer and the second layer.

Thompson, Dane (Inventor); Wang, Guoan (Inventor); Kingsley, Nickolas D. (Inventor); Papapolymerou, Ioannis (Inventor); Tentzeris, Emmanouil M. (Inventor); Bairavasubramanian, Ramanan (Inventor); DeJean, Gerald (Inventor); Li, RongLin (Inventor)

2010-01-01

344

Biologically Induced Deposition of Fine Suspended Particles by Filter-Feeding Bivalves in Land-Based Industrial Marine Aquaculture Wastewater  

Science.gov (United States)

Industrial aquaculture wastewater contains large quantities of suspended particles that can be easily broken down physically. Introduction of macro-bio-filters, such as bivalve filter feeders, may offer the potential for treatment of fine suspended matter in industrial aquaculture wastewater. In this study, we employed two kinds of bivalve filter feeders, the Pacific oyster Crassostrea gigas and the blue mussel Mytilus galloprovincialis, to deposit suspended solids from marine fish aquaculture wastewater in flow-through systems. Results showed that the biodeposition rate of suspended particles by C. gigas (shell height: 8.67±0.99 cm) and M. galloprovincialis (shell height: 4.43±0.98 cm) was 77.84±7.77 and 6.37±0.67 mg ind?1•d?1, respectively. The total solid suspension (TSS) deposition rates of oyster and mussel treatments were 3.73±0.27 and 2.76±0.20 times higher than that of the control treatment without bivalves, respectively. The TSS deposition rates of bivalve treatments were significantly higher than the natural sedimentation rate of the control treatment (Pbivalve treatments were significantly lower than those in the sediments of the control (P<0.05). It was suggested that the filter feeders C. gigas and M. galloprovincialis had considerable potential to filter and accelerate the deposition of suspended particles from industrial aquaculture wastewater, and simultaneously yield value-added biological products. PMID:25250730

Zhou, Yi; Zhang, Shaojun; Liu, Ying; Yang, Hongsheng

2014-01-01

345

Diversity of Nitrate-Reducing and Denitrifying Bacteria in a Marine Aquaculture Biofilter and their Response to Sulfide  

DEFF Research Database (Denmark)

DIVERSITY OF NITRATE-REDUCING AND DENITRIFYING BACTERIA IN A MARINE AQUACULTURE BIOFILTER AND THEIR RESPONSE TO SULFIDE B.U. Krieger 1,5, C. Schwermer 2, N. Rezakhani 5, M.A. Horn 1, A. Gieseke 2, E. Cytryn 3, D. Minz 3, J. van Rijn 4, H.L. Drake 1, A. Schramm 5 1 Dept. of Ecological Microbiology, University of Bayreuth, Bayreuth, Germany; 2 Max Planck Institute for Marine Microbiology, Bremen, Germany; 3 Institute for Soil, Water and Environmental Sciences, ARO, The Volcani Center, Bet Dagan, Israel; 4 Faculty of Agricultural, Food And Environmental Quality Sciences, The Hebrew University of Jerusalem, Rehovot, Israel; 5 Dept of Biological Sciences, Microbiology, University of Aarhus, Denmark Conventional aquaculture systems release nitrogen compounds and organic matter into marine environments. As an environmentally-friendly alternative, a zero-discharge mariculture system recently was developed containing a 3-stage biofilter for nitrification, denitrification/anaerobic sludge digestion, and sulfide oxidation. Sulfate reduction in the anaerobic part of the system leads to sulfide concentrations exceeding 5 mM, which may affect nitrate reduction and denitrification. Sulfide can inhibit nitrous oxide reductase, trigger a shift from denitrification to dissimilatory nitrate reduction to ammonium (DNRA), or be used as electron donor for nitrate reduction. The goal of this study was to identify and isolate nitrate-reducing and denitrifying bacteria from the biofilter and to investigate their response to sulfide concentrations relevant for the system. Almost 500 nitrate-consuming isolates were screened by 16S rRNA gene-RFLP; for each RFLP pattern representatives were sequenced. In total, 40 different strains were identified, some of them novel species, mostly affiliating with Alphaproteobacteria but also including Beta- and Gammaproteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria. The diversity of the isolates was compared to the cultivation-independent diversity of nitrate-reducing and denitrifying bacteria based on narG and nosZ as functional marker genes. Growth experiments revealed great differences in sulfide-tolerance among isolates, ranging from < 50 µM to 5 mM; some strains were also able to oxidize sulfide. Increasing sulfide concentrations generally resulted in increased nitrous oxide production. Batch incubations of anaerobic sludge with 15N-nitrate confirmed the in situ relevance of these results and indicated a sulfide-induced shift from denitrification to DNRA.

Krieger, Bärbel; Schwermer, Carsten U.

2006-01-01

346

Lactococcus garvieae infections in humans: possible association with aquaculture outbreaks.  

Science.gov (United States)

Lactococcus garvieae is an important pathogen in aquaculture, outbreaks of which significantly affect production. It is a rare pathogen with a low virulence in human infection. The relation between the aquaculture outbreak and the human infection has not been clarified. Prospective and retrospective epidemiologic surveillance of the four patients with L. garvieae infection between 2000 and 2003 and their relations to the aquaculture outbreaks of L. garvieae were conducted. All the four patients with L. garvieae infection were associated with gastrointestinal disorders. Three of the four patients gave a history of consuming raw fish and in three of the four patients, the infection occurred in summer between June and August while there is a decrease of fisheries production and an increase in L. garvieae infection in aquaculture farms. There was a 100% identity of 16S rDNA sequence of L. garvieae isolates from patient 1 and from the squid muscle obtained from the restaurant where patient 1 consumed the raw fish. Sporadic occurrence of L. garvieae infection in human appears to correlate with the seasonal aquaculture outbreaks of L. garvieae infection. The presence of gastro-intestinal disorder may facilitate L. garvieae infection. PMID:16704679

Wang, C-Y C; Shie, H-S; Chen, S-C; Huang, J-P; Hsieh, I-C; Wen, M-S; Lin, F-C; Wu, D

2007-01-01

347

Human Health Consequences of Use of Antimicrobial Agents in Aquaculture  

DEFF Research Database (Denmark)

Intensive use of antimicrobial agents in aquaculture provides a selective pressure creating reservoirs of drug-resistant bacteria and transferable resistance genes in fish pathogens and other bacteria in the aquatic environment. From these reservoirs, resistance genes may disseminate by horizontal gene transfer and reach human pathogens, or drug-resistant pathogens from the aquatic environment may reach humans directly. Horizontal gene transfer may occur in the aquaculture environment, in the food chain, or in the human intestinal tract. Among the antimicrobial agents commonly used in aquaculture, several are classified by the World Health Organisation as critically important for use in humans. Occurrence of resistance to these antimicrobial agents in human pathogens severely limits the therapeutic options in human infections. Considering the rapid growth and importance of aquaculture industry in many regions of the world and the widespread, intensive, and often unregulated use of antimicrobial agents in thisarea of animal production, efforts are needed to prevent development and spread of antimicrobial resistance in aquaculture to reduce the risk to human health.

Heuer, Ole Eske; Kruse, H.

2009-01-01

348

Thermodynamic potential of electrons and phonons system of disordered alloy  

CERN Document Server

The cluster decomposition for the delayed two-time Green functions and the disordered crystal dynamic potential is obtained with an account of the electron-phonon and electron-electron interactions. The system electron states are described within the frames of the multizone strong coupling model. The calculations are based on the diagram technique for the Green temperature functions. The coherent potential approximation is chosen as the zero mononode approximation in this cluster decomposition method. It is shown that the processes of the contributions of the elementary excitations scattering on the clusters decrease with the cluster nodes number growth in the cluster in correspondence with certain small parameters. The analytical evaluations of the electron-phonon interaction impact on the electron energy spectrum of the ordering alloy are made in the monozone model. The possibility of applying the obtained results for describing the strong electron correlations impact on the electron structure and propertie...

Repetskij, S P

2002-01-01

349

Use of Geothermal Energy for Aquaculture Purposes - Phase III  

Energy Technology Data Exchange (ETDEWEB)

This project, financed by the Pacific Northwest Regional Commission (PNRC), was designed to provide information to evaluate the best methods to use for intensive aquaculture of freshwater prawns, Macrobrachium rosenbergii, using geothermal energy. The freshwater prawn is a tropical organism and is native to southeast Asia. Earlier projects at Oregon Institute of Technology have shown the feasibility of culturing this aquatic animal in geothermal water. This phase of the project was designed to investigate intensive culture of this animal as well as the advantages of growing rainbow trout, ornamental tropical fin fish, and mosquito fish, Gambusia affnis, for vector control using geothermal energy. The research data collected on the prawns was obtained from the stocking and sampling of two 0.2- ha (half-acre) ponds constructed as a part of the project. The ponds are equipped with recording monitors for temperature and flow. The geothermal energy used is the geothermal effluent from the Oregon Institute of Technology heating system. This water is of potable quality and ranges in temperature from 50 to 70oC. The geothermal water used in the ponds is controlled at 27oC, ± 2oC, by using thermostats and solenoid valves. A small building next to the ponds contains facilities for hatching larvae prawns and tanks for growing post-larvae prawns. The hatchery facility makes the project self-sustaining. The hatchery was obtained as part of an earlier PNRC project.

Johnson, W.C.; Smith, K.C.

1981-09-01

350

Electron attachment and ion mobility in hydrocarbons and related systems  

International Nuclear Information System (INIS)

During the last two decades, a firm base for the emerging field of liquid state electronics (LSE) has developed through studies of the transport and reaction properties of excess electrons in a variety of liquid-phase systems. Pulse-conductivity techniques were used in many of these studies to measure the mobilities of electrons and ions in pure liquids as well as the rate constants of electron attachment to a wide variety of electron-accepting solutes. Results obtained through such studies have interdisciplinary implications that are described in the discussion that follows which includes examples of the contributions of LSE to physics, chemistry and biology. 42 refs

351

Optical spectroscopy of strongly correlated electron systems  

Energy Technology Data Exchange (ETDEWEB)

In this thesis, both time-resolved, nonlinear optical spectroscopy and linear spectroscopy are used to investigate the interactions and dynamics of elementary excitations in strongly correlated electron systems. In the first part, we investigate the renormalization of magnetic elementary excitations in the transition metal oxide Cr{sub 2}O{sub 3}. We have created a non-equilibrium population of antiferromagnetic spin waves and characterized its dynamics, using frequency- and time-resolved optical spectroscopy of the exciton-magnon transition. We observed a time-dependent pump-probe line shape, which results from excitation induced renormalization of the spin wave band structure. We present a model that reproduces the basic characteristics of the data, in which we postulate the optical nonlinearity to be dominated by interactions with long-wavelength spin waves, and the dynamics due to spin wave thermalization. Using linear spectroscopy, coherent third-harmonic generation and pump-probe experiments, we measured the optical properties of the charge-transfer (CT) gap exciton in Sr{sub 2}CuO{sub 2}Cl{sub 2}, an undoped model compound for high-temperature superconductors. A model is developed which explains the pronounced temperature dependence and newly observed Urbach tail in the linear absorption spectrum by a strong, phonon-mediated coupling between the charge-transfer exciton and ligand field excitations of the Cu atoms. The third-order nonlinear optical susceptibility within the Cu-O plane of Sr{sub 2}CuO{sub 2}Cl{sub 2} is fully characterized in both amplitude and phase, and symmetry based conclusions are made with respect to the spatial arrangement of the underlying charge distribution. Theoretical considerations ascribe a newly reported resonance in the third-order nonlinear susceptibility at 0.7 eV to a three-photon transition from the ground state to the charge-transfer exciton. An even parity intermediate state of Cudd character, is found to contribute to the transition. Finally, preliminary results of time-resolved pump-probe spectroscopy confirm that the CT exciton or one of its constituent parts couples strongly to phonons, and we suggest ultrafast thermalization with the lattice as the dominating mechanism underlying the dynamical properties.

Schumacher, Andreas B.

2001-02-27

352

Genetic considerations for mollusk production in aquaculture: current state of knowledge  

OpenAIRE

In 2012, world mollusk production in aquaculture reached a volume of 15,171,000 tons, representing 23% of total aquaculture production and positioning mollusks as the second most important category of aquaculture products (fishes are the first). Clams and oysters are the mollusk species with the highest production levels, followed in descending order by mussels, scallops, and abalones. In view of the increasing importance attached to genetic information on aquaculture, which can help with goo...

Astorga, Marcela P.

2014-01-01

353

Aquaculture investigations with nuclear energy techniques  

International Nuclear Information System (INIS)

The culture of aquatic organisms, especially that of fishes under controlled conditions, up to their harvesting, processing, commercialization and consumption, has been pointed out as an activity that produces a lot of benefits, among them: the obtention high proteic valued food, the incorporation to the economy of lands not usefull for agriculture activities, the increment of fishing resources, the recycling of organic matter produced in the units, the regional development, the generation of employment, technologies and foreign currencies. Several research areas are identified that can be developed, using the nuclear technologies, for example in the reproduction, nutrition, diagnose and control of illnesses, environmental monitoring and quality certification of products. In the concerning to the Venezuelan aquaculture, investigations are required that need to use those techniques. For example: 1) Production of autochthonous inductive agents, by means of radioinmunoenssay (RIA), to determine the gonadotropines coming from the hypophysis of fish cultivated with the purpose of gathering the glands in its best moment, to generate the final maturation and spawn in autochthonous species. 2) Genetic improvement of cultivated species through the knowledge of the genetic load of different lines and breeds found in the natural means, and to achieve its maintenance to solve inbreeding problems, in autochthonous species aswell in as in exotic ones, by the use of marking techniques (ADE, RFLA and microsatellite techniques). 3) Nutritional and feeding studies of species under commertial culture, especially on the effect of the aflatoxins in the inputs or the portions, substances that influence in a negative way the aquatic nutrition. In this case, competitive immunoassays of enzymes bounded (ELISA) and radioinmunoessays. 4) Illness diagnose, by means of the ELISA kit, specifically of the more common illness in fishes cultivated in the country

354

Electronic solutions for Ethiopian health sector : electronic medical record (EMR) system  

OpenAIRE

This thesis gives general information about Ethiopia and addresses the electronic solutions planned and designed by Federal Ministry of Health (FMoH) mainly electronic medical records system (EMRS) in Ethiopia. As of research methodology I used site observation in government hospitals in Addis Ababa and interview doctors, health officers and high commissioners from federal health bureau. Based on my findings the federal bureau has done and is doing several electronic solutions for health...

Mengesha, Tewodros

2011-01-01

355

Magic Angle Electron Energy Loss Spectroscopy (MAEELS) of core electron excitation in anisotropic systems  

CERN Document Server

A general theory for the core-level electron excitation of anisotropic systems using angular integrated electron energy-loss spectroscopy has been derived. We show that it is possible to define a magic angle condition at which the specimen orientation has no effect on the electron energy-loss spectra. We have not only resolved the existing discrepancy between different studies of the magic angle condition, but also extended its applicability to all anisotropic systems. We have demonstrated that magic angle electron energy loss spectroscopy is equivalent to the orientation averaged EELS, although the specimen remains stationary. Our analysis provides the theoretical framework for the comparison between theoretical calculation and experimental measurement of core-level electron excitation spectra in anisotropic systems. In addition to MAEELS, we have also discovered a magic orientation condition which will also give rise to orientationally averaged spectra. It's relation with the magic angle X-ray absorption sp...

Sun, Y K

2004-01-01

356

Electron beam sterilization using an integrated systems approach  

International Nuclear Information System (INIS)

The sterilization of medical disposables is a complex process and requires a sophisticated system to meet today's stringent requirements. Such a system is in use today using electron beam sterilization from a Dynamitron accelerator. The process system components are described as is their functionality as part of an integrated system. Certain information is omitted to observe the confidentiality of the user. (orig.)

357

Electronics modules for particle beam monitoring system  

International Nuclear Information System (INIS)

Electronics modules, both digital and analogue for the extracted particle beam diagnostics, made in the Vector-SUMMA standard are described. A set of these modules together with a number of universal ones well allow to solve all main problems of extracted beam diagnostics. 12 refs.; 10 figs

358

DNA and microfluidics: Building molecular electronics systems  

International Nuclear Information System (INIS)

The development of molecular electronics using DNA molecules as the building blocks and using microfluidics to build nanowire arrays is reviewed. Applications of DNA conductivity to build sensors and nanowire arrays, and DNA conjugation with other nanostructures, offers an exciting opportunity to build extremely small analytical devices that are suitable for single-molecule detection and also target screening

359

Electron multiplier-ion detector system  

International Nuclear Information System (INIS)

This patent relates to an improved ion detector for use in mass spectrometers for pulse counting signal ions which may have a positive or a negative charge. The invention combines a novel electron multiplier with a scintillator type of ion detector. It is a high vacuum, high voltage device intended for use in ion microprobe mass spectrometers

360

Variational Monte Carlo method for electron-phonon coupled systems  

Science.gov (United States)

We develop a variational Monte Carlo (VMC) method for electron-phonon coupled systems. The VMC method has been extensively used for investigating strongly correlated electrons over the last decades. However, its applications to electron-phonon coupled systems have been severely restricted because of its large Hilbert space. Here, we propose a variational wave function with a large number of variational parameters, which is suitable and tractable for systems with electron-phonon coupling. In the proposed wave function, we implement an unexplored electron-phonon correlation factor, which takes into account the effect of the entanglement between electrons and phonons. The method is applied to systems with diagonal electron-phonon interactions, i.e., interactions between charge densities and lattice displacements (phonons). As benchmarks, we compare VMC results with previous results obtained by the exact diagonalization, the Green function Monte Carlo method and the density matrix renormalization group for the Holstein and Holstein-Hubbard model. From these benchmarks, we show that the present method offers an efficient way to treat strongly coupled electron-phonon systems.

Ohgoe, Takahiro; Imada, Masatoshi

2014-05-01

361

The electronic identification, signature and security of information systems  

Directory of Open Access Journals (Sweden)

Full Text Available The contribution deals with the actual methods and technologies of information and communication systems security. It introduces the overview of electronic identification elements such as static password, dynamic password and single sign-on. Into this category belong also biometric and dynamic characteristics of verified person. Widespread is authentication based on identification elements ownership, such as various cards and authentication calculators. In the next part is specified a definition and characterization of electronic signature, its basic functions and certificate categories. Practical utilization of electronic signature consists of electronic signature acquirement, signature of outgoing email message, receiving of electronic signature and verification of electronic signature. The use of electronic signature is continuously growing and in connection with legislation development it exercises in all resorts.

Horovèák Pavel

2002-12-01

362

Note on Modern Trends in Heavy Vehicle Electrical Electronic systems  

Directory of Open Access Journals (Sweden)

Full Text Available The paper presents an overview of some of the aerospace control systems that are being successfully adopted in the field of Armoured Fighting Vehicles. An automatic electronic transmission controller for an epicyclic gear box with a torque converter to select the forward and reverse speeds in a sequential logic has been developed. Transducers developed for monitoring various engine and transmission parameters are being used for Electronic Fuel Injection (EFI, variable valve timings and electronic governing.

B. S. Sastry

2014-03-01

363

Impact of Oceanographic Environmental Shifts and Atmospheric Events on the Sustainable Development of Coastal Aquaculture: A Case Study of Kelp and Scallops in Southern Hokkaido, Japan  

Directory of Open Access Journals (Sweden)

Full Text Available We provide an overview of selected recent operational applications of satellite remote sensing and marine Geographic Information Systems (GIS procedures to the practice of sustainable aquaculture in southern Hokkaido, Japan, focusing mainly on kelp and scallop aquaculture. We also developed a suitable aquaculture site-selection model (SASSM for suspension culture of Gagome (a kelp species in the same region. Models for Japanese kelp and Gagome showed that the distributions of the most suitable areas for both species overlapped. Competition between kelps was especially marked along the coastline between Hakodate and Esan. In addition, we examined the impact of oceanographic environmental changes and atmospheric events on scallop and kelp aquaculture sites, demonstrating that variations in the coastal Oyashio Current and the Tsugaru Warm Current significantly influenced the growth and harvesting seasons of scallops and kelps in Funka Bay and other sections of southern Hokkaido. Because a strong El Niño event occurred in 2010, January of that year was extremely cold. The proportion of suitable areas for both scallops and kelps during their respective growing seasons contracted in 2010. Thus, shifts in oceanographic and atmospheric conditions should be incorporated into sustainability management planning for coastal scallop and kelp aquaculture in southern Hokkaido.

Yang Liu

2015-01-01

364

Fisheries and aquaculture industries involvement to control product health and quality safety to satisfy consumer-driven objectives on retail markets in Europe  

Energy Technology Data Exchange (ETDEWEB)

Over the past years the export of agricultural and fishery products from developing countries has substantially increased to markets within the OECD. Retailers and importers are expanding their international operations to meet consumer demands for year-round delivery of products. Moreover, consumers have become increasingly concerned about the safety of food, including those derived from aquatic resources [FAO/NACA/WHO Joint Study Group, 1999. Report food safety issues associated with products from aquaculture. WHO Technical Report Series No 883: VII, pp. 1-55]. Governments and leading businesses are responding by imposing new safety regulations and standards to the international food system (e.g. HACCP, EUREP-GAP), product liability and labeling [Reilly, A., Howgate, P., Kaeferstein, F., 1997. Safety hazards and the application of HACCP in aquaculture. In: Proceedings of the Second International Conference on Fish Inspection and Quality Control: A Global Focus, Arlington, VA, 19-24 May 1996. Technomic Publishing, Lancaster, PA, pp. 353-373]. Initial concerns for imports of aquacultural products from developing to industrialized countries focussed on bacterial contamination [Buras, N. 1993. Microbial safety of produce from wastewater-fed aquaculture. In: Pullin, R.V.C., Rosenthal, H., MacLean, J.L.(Eds.), Proceedings of ICLARM Conferences, vol. 31, pp. 285-295]. Today, if trade opportunities are to be maintained, these countries must adapt to a full array of regulations and standards. This paper describes four scenarios in aquaculture and fishing product trade between developing countries and countries in the European Union.

Roth, Eva [University of South Denmark, Department of Environmental and Business Economics, Niels Bohrs vej 9, DK-6700 Esbjerg (Denmark); Institute for Marine Research, University Kiel, Duesternbrooker Weg 20, 24105 Kiel (Germany); Rosenthal, Harald [University of South Denmark, Department of Environmental and Business Economics, Niels Bohrs vej 9, DK-6700 Esbjerg (Denmark); Institute for Marine Research, University Kiel, Duesternbrooker Weg 20, 24105 Kiel (Germany)

2006-07-01

365

Conductivity of the electron-impurity system  

International Nuclear Information System (INIS)

The free-carrier absorption of electromagnetic radiation due to the presence of static scatterers is examined taking into account the electron-electron interaction, the plasma-phonon polar coupling and the plasma anisotropy. For the case of strong coupling in the isotropic plasma the absorption due to the collective-mode excitation processes is, for frequencies just above the plasmon-like collective mode frequency, shown to be dominant over the absorption due to single-particle excitations. The expression for the frequency-dependent absorptive part of the conductivity due to the long-wavelength collective-mode excitations is derived for the case of multicomponent anisotropic degenerate plasma (e.g. lead chalcogenides). The results are discussed in detail and compared with available experimental data for n-PbSe. The comparison with the previous theories is also given. (author)

366

Electronic transport in disordered interacting systems  

OpenAIRE

We numerically investigate the transport properties of disordered interacting electrons in three dimensions in the metallic as well as in the insulating phases. The disordered many-particle problem is modeled by the quantum Coulomb glass which contains a random potential, long-range unscreened Coulomb interactions and quantum hopping between different sites. We have recently developed the Hartree-Fock based diagonalization (HFD) method which amounts to diagonalizing the Hami...

Vojta, Thomas; Epperlein, Frank

1998-01-01

367

Electronic resource management systems a workflow approach  

CERN Document Server

To get to the bottom of a successful approach to Electronic Resource Management (ERM), Anderson interviewed staff at 11 institutions about their ERM implementations. Among her conclusions, presented in this issue of Library Technology Reports, is that grasping the intricacies of your workflow-analyzing each step to reveal the gaps and problems-at the beginning is crucial to selecting and implementing an ERM.

Anderson, Elsa K

2014-01-01

368

Energy Transformation in Molecular Electronic Systems  

Energy Technology Data Exchange (ETDEWEB)

This laboratory has developed many new ideas and methods in the electronic spectroscopy of molecules. This report covers the contract period 1993-1995. A number of the projects were completed in 1996, and those papers are included in the report. The DOE contract was terminated at the end of 1995 owing to a reorganizational change eliminating nationally the projects under the Office of Health and Environmental Research, U. S. Department of Energy.

Kasha, Michael

1999-05-17

369

The electronics readout system for the OPAL Vertex Drift Chamber  

International Nuclear Information System (INIS)

The Vertex Drift Chamber for the OPAL experiment at LEP provides high quality track co-ordinates using multi-hit sub-nanosecond timing to detect the drifted electrons. This paper explains the electronic techniques that have been devised and implemented for the detector. The overall performance of the system is demonstrated with measurements from the final OPAL chamber. (author)

370

F-electron systems: Pushing band theory  

Energy Technology Data Exchange (ETDEWEB)

The f-electron orbitals have always been the incomplete atomic shell acting as a local moment weakly interacting with the remaining electronic structure'' in the minds of most people. So examining them using a band theory where one views them as itinerant once was -- and to some extent even today still is -- considered with some skepticism. Nonetheless, a very significant community has successfully utilized band theory as a probe of the electronic structure of the appropriate actinides and rare earths. Those people actually using the approach would be the first to declare that it is not the whole solution. Instead, one is pushing and even exceeding its limits of applicability. However, the appropriate procedure is to push the model consistently to its limits, patch where possible, and then look to see where discrepancies remain. I propose to offer a selected review of past developments (emphasizing the career to date of A. J. Freeman in this area), offer a list of interesting puzzles for the future, and then make some guesses as to the techniques one might want to use. 27 refs.

Koelling, D.D.

1990-08-01

371

Infrastructures of the System for Developing Electronic Health Record  

Directory of Open Access Journals (Sweden)

Full Text Available The overall objective of a health system is to improve health through reducing disease, disability and death. Accomplishment of this goal depends on the worldwide integrated and coordinated care continuity. Information transmission is a prerequisite to ensure the continuity of care. Widespread acceptance of health information and communication technology (HICT and developing systems such as Electronic Health Record (EHR, have changed the health care industry. Electronic Health Record is the main part of information management in an integrated health care system. Electronic health record provides access to all health information at organizational, regional, national and international levels and allows for the patient's health data [usually with geographical distribution in several health information systems] to become integrated. Since Electronic health record integrates all care events data, it can make data sharing possible between all care providers to consequently minimize the repeated diagnostic tests, and drug and treatment interactions. Furthermore, Also health care professionals can easily access to patient information at any time and this could lead to improving the quality of care and reduce costs. Accordingly, a productive system is required to provide the electronic health record. Given the significance of the electronic health record and its generating system in improvement of care quality and reducing the health care costs, authors decided to study the needs for developing the national EHR system (NHIN The main focus of this paper was on selecting material related to the system developing an EHR and it prerequisites. Electronic health record system is a new source of valuable intelligence of real world for the whole health care industry. Electronic health record system includes people, rules, standards, storage and processing equipments, communication and support facilities. To shape this, existence of components and their coordination is necessary. Electronic health record system are established to enhance patient care and its outcome, increase efficiency, improving the availability of information and minimizing the medical errors. With the Europe union formation that in fact was an important step toward globalization, the electronic health record passed the national borders and turned into a global concept to make possible the worldwide integration and sharing of the health data. Therefore international standards are needed to share patient health information between national health systems and across borders. Infrastructure or national information network existence of proper hardware and software and finally participation of all stakeholders are necessary to develop the system. So it is necessary to prepare the infrastructures needed for development of the system in our country. Since EHR has a universal concept, it is needed to create a lifelong health information record for every individual accessible in every point in the world.

Hamid Moghaddasi

2011-01-01

372

Automotive mechatronics automotive networking, driving stability systems, electronics  

CERN Document Server

As the complexity of automotive vehicles increases this book presents operational and practical issues of automotive mechatronics. It is a comprehensive introduction to controlled automotive systems and provides detailed information of sensors for travel, angle, engine speed, vehicle speed, acceleration, pressure, temperature, flow, gas concentration etc. The measurement principles of the different sensor groups are explained and examples to show the measurement principles applied in different types. Contents Basics of mechatronics.- Architecture.- Electronic control unit.- Software development.- Basic principles of networking.- Automotive networking.- Bus systems.- Automotive sensors.- Sensor measuring principles.- Sensor types.- Electric actuators.- Electrohydraulic actuators.- Electronic transmission control.- Electronic transmission control unit.- Modules for transmission control.- Antilock braking system.- Traction control system.- Electronic stability program.- Automatic brake functions.- Hydraulic modu...

2015-01-01

373

8 CFR 217.5 - Electronic System for Travel Authorization.  

Science.gov (United States)

...Electronic System for Travel Authorization (ESTA), from CBP. In order to receive...States. (c) Required elements. ESTA will collect such information as the... A travel authorization issued under ESTA will be valid for a period of two...

2010-01-01

374

System and method for compressive scanning electron microscopy  

Energy Technology Data Exchange (ETDEWEB)

A scanning transmission electron microscopy (STEM) system is disclosed. The system may make use of an electron beam scanning system configured to generate a plurality of electron beam scans over substantially an entire sample, with each scan varying in electron-illumination intensity over a course of the scan. A signal acquisition system may be used for obtaining at least one of an image, a diffraction pattern, or a spectrum from the scans, the image, diffraction pattern, or spectrum representing only information from at least one of a select subplurality or linear combination of all pixel locations comprising the image. A dataset may be produced from the information. A subsystem may be used for mathematically analyzing the dataset to predict actual information that would have been produced by each pixel location of the image.

Reed, Bryan W

2015-01-13

375

Quantum Entanglement and Electron Correlation in Molecular Systems  

CERN Document Server

We study the relation between quantum entanglement and electron correlation in quantum chemistry calculations. We prove that the Hartree-Fock (HF) wave function does not violate Bell's inequality, thus is not entangled while the configuration interaction (CI) wave function is entangled since it violates Bell's inequality. Entanglement is related to electron correlation and might be used as an alternative measure of the electron correlation in quantum chemistry calculations. As an example we show the calculations of entanglement for the H$_2$ molecule and how it is related to electron correlation of the system, which is the difference between the exact and the HF energies.

Wang, H; Kais, Sabre; Wang, Hefeng

2007-01-01

376

Determination of radiation resistant of electronic components in robot system  

Energy Technology Data Exchange (ETDEWEB)

We investigated the characteristic change for the electronic components of the systems which were used in radiation area, when those were exposured by gamma rays. Bipolar transistor, FET, TTL, CMOS, operational amplifier, some capacitors, and several electronic components were selected for experiment. We applied irradiated gamma ray to the electronic components in the range of 10{sup 6} rad, by {sup 6}0Co(KAERI). We made up appropriate assessment circuit for each electronic component during the performance test, and assessed the reliability and radiation-resistance of them for the each radiation irradiation. (author). 59 refs., 35 figs., 8 tabs.

Kang, Hee Dong [Kyungpook National University, Taegu (Korea); Kim, Do Sung [Taegu University, Taegu (Korea); Woo, Hong [Kyungsan University, Kyungsan (Korea)

1998-04-01

377

36 CFR 1236.20 - What are appropriate recordkeeping systems for electronic records?  

Science.gov (United States)

...recordkeeping systems for electronic records? 1236.20...Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION RECORDS MANAGEMENT ELECTRONIC RECORDS MANAGEMENT Additional Requirements for Electronic Records §...

2010-07-01

378

36 CFR 1236.26 - What actions must agencies take to maintain electronic information systems?  

Science.gov (United States)

...agencies take to maintain electronic information systems...Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION RECORDS MANAGEMENT ELECTRONIC RECORDS MANAGEMENT Additional Requirements for Electronic Records §...

2010-07-01

379

Seafloor earthquake measurement system. Volume 2: Electronic hardware description  

Science.gov (United States)

The Seafloor Earthquake Measurement System, a unique instrument for collecting seismic motion data from remote ocean floor sites is described. The electronic systems of the data gathering and the command units are described, as well as the acoustic telemetry systems which provide the communication link.

Ryerson, D. E.

1981-12-01

380

Monitoring and control system of the Saclay electron linear accelerator  

International Nuclear Information System (INIS)

A description is given of the automatic monitoring and control system of the 60MeV electron linear accelerator of the Centre d'Etudes Nucleaires de Saclay. The paper is mostly concerned with the programmation of the system. However, in a real time device, there is a very close association between computer and electronics, the latter are therefore described in details and make up most of the paper

381

Infrastructures of the System for Developing Electronic Health Record  

OpenAIRE

The overall objective of a health system is to improve health through reducing disease, disability and death. Accomplishment of this goal depends on the worldwide integrated and coordinated care continuity. Information transmission is a prerequisite to ensure the continuity of care. Widespread acceptance of health information and communication technology (HICT) and developing systems such as Electronic Health Record (EHR), have changed the health care industry. Electronic Health Record is the...

Hamid Moghaddasi; Azamossadat Hosseini; Farkhondeh Asadi; Raheleh Ganjali

2011-01-01

382

An Electronic Voting System Using GSM Mobile Technology  

OpenAIRE

Electronic voting systems have the potential to improve traditional voting procedures by providing added convenience and flexibility to the voter. Numerous electronic voting schemes have been proposed in the past, but most of them have failed to provide voter authentication in an efficient and transparent way. On the other hand, GSM (Global System for Mobile communications) is the most widely used mobile networking standard. There are more than one billion GSM users worldwid...

Feng, Yang; Ng, Siaw-lynn; Schwiderski-grosche, Scarlet

2008-01-01

383

Control electronics of the PEP RF system  

International Nuclear Information System (INIS)

The operation of the major components used for controlling the phase and field level of the PEP RF cavities is described. The control electronics of one RF station is composed of several control loops: each cavity has a tuners' servo loop which maintains the frequency constant and also keeps the fields of each cavity balanced; the total gap voltage developed by a pair of cavities is regulated by a gap voltage controller; finally, the phase variation along the amplification chain, the klystron and the cavities are compensated by a phase lock loop. The design criteria of each loop are set forth and the circuit implementation and test results are presented

384

An Electronic Pressure Profile Display system for aeronautic test facilities  

Science.gov (United States)

The NASA Lewis Research Center has installed an Electronic Pressure Profile Display system. This system provides for the real-time display of pressure readings on high resolution graphics monitors. The Electronic Pressure Profile Display system will replace manometer banks currently used in aeronautic test facilities. The Electronic Pressure Profile Display system consists of an industrial type Digital Pressure Transmitter (DPI) unit which interfaces with a host computer. The host computer collects the pressure data from the DPI unit, converts it into engineering units, and displays the readings on a high resolution graphics monitor in bar graph format. Software was developed to accomplish the above tasks and also draw facility diagrams as background information on the displays. Data transfer between host computer and DPT unit is done with serial communications. Up to 64 channels are displayed with one second update time. This paper describes the system configuration, its features, and its advantages over existing systems.

Woike, Mark R.

1990-01-01

385

ANALYSIS OF ELECTRONIC VOTING SYSTEM IN VARIOUS COUNTRIES  

Directory of Open Access Journals (Sweden)

Full Text Available India is the world’s largest democracy with a population of more than 1 billion; India has an electorate of more than 668 million and covers 543 parliamentary constituencies. Voting is the bridge between the governed and government. The last few years have brought a renewed focus on to the technology used in the voting process. The current voting system has many security holes, and it is difficult to prove even simple security properties about them. A voting system that can be proven correct has many concerns. There are some reasons for a government to use electronic systems are to increase elections activities and to reduce the elections expenses. Still there is some scope of work in electronic voting system because there is no way of identification by the electronic voting system whether the user is authentic or not and securing electronic voting machine from miscreants. This paper provides an overview of the experiences of other countries using electronic voting machine. The comparative focus is on the adoption of electronic voting systems adopted at the international level.

Sanjay Kumar,

2011-05-01

386

Nutrients' removal from aquaculture wastewater using the macroalgae Gracilaria birdiae  

Energy Technology Data Exchange (ETDEWEB)

Intensive aquaculture releases large amount of nutrients into aquatic ecosystems and can lead to eutrophication of coastal waters. Studies conducted in aquaculture systems have demonstrated that the seaweeds are efficient in reducing nutrients and at the same time provides extra income, when species of economic importance are used. This study was conducted to evaluate whether Gracilaria birdiae could be cultivated efficiently for the production of useful algal biomass and removal of nutrients from shrimp pond effluents. The results obtained showed a gradual increase in biomass and relative growth rate (RGR) over the experimental period. Mean RGR between the weeks varied significantly (p < 0.01), reaching a maximum of 3.6 {+-} 0.35% d{sup -1} and a minimum of 1.6 {+-} 0.52% d{sup -1}. The mean for the whole period was 2.6% d{sup -1}. The biofiltration capacity of G. birdiae was confirmed by the significantly reduced concentration of the three nutrients analyzed (PO{sub 4}{sup 3-}, NH{sub 4}{sup +} and NO{sub 3}{sup -}) over the study period. The concentration of PO{sub 4}{sup 3-} decreased by 93.5%, NH{sub 4}{sup +} by 34% and NO{sub 3}{sup -} by 100% after the 4-week experimental period. The results obtained in this study indicated that G. birdiae can be used in aquaculture systems as a biofilter. In addition, the macroalgae biomass produced offers alternative source of raw material for the extraction of the phycocolloid agar, human food and animal feed. (author)

Marinho-Soriano, E.; Nunes, S.O.; Carneiro, M.A.A.; Pereira, D.C. [Universidade Federal do Rio Grande do Norte, Depto. de Oceanografia e Limnologia, Via Costeira, Praia de Mae Luiza, s/n, Natal, RN 59014-100 (Brazil)

2009-02-15

387

Plasma dispersion of multisubband electron systems over liquid helium  

CERN Document Server

Density-density response functions are evaluated for nondegenerate multisubband electron systems in the random-phase approximation for arbitrary wave number and subband index. We consider both quasi-two-dimensional and quasi-one- dimensional systems for electrons confined to the surface of liquid helium. The dispersion relations of longitudinal intrasubband and transverse intersubband modes are calculated at low temperatures and for long wavelengths. We discuss the effects of screening and two-subband occupancy on the plasmon spectrum. The characteristic absorption edge of the intersubband modes is shifted relatively to the single-particle intersubband separation and the depolarization shift correction can be significant at high electron densities.

Sokolov, S S; Sokolov, Sviatoslav S.; Studart, Nelson

2000-01-01

388

Counter-insurgents of the blue revolution? Parasites and diseases affecting aquaculture and science.  

Science.gov (United States)

Aquaculture is the fastest-growing segment of food production and is expected to supply a growing portion of animal protein for consumption by humans. Because industrial aquaculture developed only recently compared to industrial agriculture, its development occurred within the context of a growing environmental awareness and acknowledgment of environmental issues associated with industrial farming. As such, parasites and diseases have become central criticisms of commercial aquaculture. This focus on parasites and diseases, however, has created a nexus of opportunities for research that has facilitated considerable scientific advances in the fields of parasitology and aquaculture. This paper reviews Myxobolus cerebralis , Lepeophtheirus salmonis , white spot syndrome virus, and assorted flatworms as select marquee aquaculture pathogens, summarizes the status of the diseases caused by each and their impacts on aquaculture, and highlights some of the significant contributions these pathogens have made to the science of parasitology and aquaculture. PMID:25260074

Blaylock, Reginald B; Bullard, Stephen A

2014-12-01

389

Advanced Power Electronic Interfaces for Distributed Energy Systems Part 1: Systems and Topologies  

Energy Technology Data Exchange (ETDEWEB)

This report summarizes power electronic interfaces for DE applications and the topologies needed for advanced power electronic interfaces. It focuses on photovoltaic, wind, microturbine, fuel cell, internal combustion engine, battery storage, and flywheel storage systems.

Kramer, W.; Chakraborty, S.; Kroposki, B.; Thomas, H.

2008-03-01

390

BPM system of electron linac and its application  

International Nuclear Information System (INIS)

The beam profile measurement (BPM) system of 30 MeV linac in Beijing Free Electron Laser Laboratory (BFELL) is described. The BPM consists of remote control phosphor screen, four TV cameras, an image video signal processor and a computer system. The profile, position, emittance and distribution of electron beam for injection and output of the linac have been measured with it. The spatial resolution of the system is approximately 0.1 mm. The precision of measurement of beam width is about 0.05 mm that meets the requirement of BFEL. The system have been used on line over two years and have met the needs for test of BFEL

391

NASA three-laser airborne differential absorption lidar system electronics  

Science.gov (United States)

The system control and signal conditioning electronics of the NASA three laser airborne differential absorption lidar (DIAL) system are described. The multipurpose DIAL system was developed for the remote measurement of gas and aerosol profiles in the troposphere and lower stratosphere. A brief description and photographs of the majority of electronics units developed under this contract are presented. The precision control system; which includes a master control unit, three combined NASA laser control interface/quantel control units, and three noise pulse discriminator/pockels cell pulser units; is described in detail. The need and design considerations for precision timing and control are discussed. Calibration procedures are included.

Allen, R. J.; Copeland, G. D.

1984-12-01

392

Large magnetocapacitance in electronic ferroelectric manganite systems  

Energy Technology Data Exchange (ETDEWEB)

We have observed a sizable positive magnetocapacitance (?5%–90%) in perovskite Pr{sub 0.55}Ca{sub 0.45}MnO{sub 3} and bilayer Pr(Sr{sub 0.1}Ca{sub 0.9}){sub 2}Mn{sub 2}O{sub 7} system under 5?T magnetic field across 20–100?K below the magnetic transition point T{sub N}. The magnetodielectric effect, on the other hand, exhibits a crossover: (a) from positive to negative for the perovskite system and (b) from negative to positive for the bilayer system over the same temperature range. The bilayer Pr(Sr{sub 0.1}Ca{sub 0.9}){sub 2}Mn{sub 2}O{sub 7} system exhibits a sizable anisotropy as well. We have also noticed the influence of magnetic field on the dielectric relaxation characteristics of these systems. These systems belong to a class of improper ferroelectrics and are expected to exhibit charge/orbital order driven ferroelectric polarization below the transition point T{sub CO}. Large magnetocapacitance in these systems shows a typical multiferroic behavior even though the ferroelectric polarization is small in comparison to that of other ferroelectrics.

Chowdhury, Ujjal; Goswami, Sudipta; Bhattacharya, Dipten, E-mail: dipten@cgcri.res.in [Nanostructured Materials Division, CSIR-Central Glass and Ceramic Research Institute, Kolkata 700032 (India); Midya, Arindam; Mandal, P. [Experimental Condensed Matter Physics, Saha Institute of Nuclear Physics, Kolkata 700064 (India); Das, Pintu [Institute of Physics, J.W. Goethe University, D-60438 Frankfurt (Germany); Mukovskii, Ya. M. [National Research Technological University, “MISiS,” Moscow 119049 (Russian Federation)

2013-11-21

393

Large magnetocapacitance in electronic ferroelectric manganite systems  

Science.gov (United States)

We have observed a sizable positive magnetocapacitance (˜5%-90%) in perovskite Pr0.55Ca0.45MnO3 and bilayer Pr(Sr0.1Ca0.9)2Mn2O7 system under 5 T magnetic field across 20-100 K below the magnetic transition point TN. The magnetodielectric effect, on the other hand, exhibits a crossover: (a) from positive to negative for the perovskite system and (b) from negative to positive for the bilayer system over the same temperature range. The bilayer Pr(Sr0.1Ca0.9)2Mn2O7 system exhibits a sizable anisotropy as well. We have also noticed the influence of magnetic field on the dielectric relaxation characteristics of these systems. These systems belong to a class of improper ferroelectrics and are expected to exhibit charge/orbital order driven ferroelectric polarization below the transition point TCO. Large magnetocapacitance in these systems shows a typical multiferroic behavior even though the ferroelectric polarization is small in comparison to that of other ferroelectrics.

Chowdhury, Ujjal; Goswami, Sudipta; Bhattacharya, Dipten; Midya, Arindam; Mandal, P.; Das, Pintu; Mukovskii, Ya. M.

2013-11-01

394

Large magnetocapacitance in electronic ferroelectric manganite systems  

International Nuclear Information System (INIS)

We have observed a sizable positive magnetocapacitance (?5%–90%) in perovskite Pr0.55Ca0.45MnO3 and bilayer Pr(Sr0.1Ca0.9)2Mn2O7 system under 5?T magnetic field across 20–100?K below the magnetic transition point TN. The magnetodielectric effect, on the other hand, exhibits a crossover: (a) from positive to negative for the perovskite system and (b) from negative to positive for the bilayer system over the same temperature range. The bilayer Pr(Sr0.1Ca0.9)2Mn2O7 system exhibits a sizable anisotropy as well. We have also noticed the influence of magnetic field on the dielectric relaxation characteristics of these systems. These systems belong to a class of improper ferroelectrics and are expected to exhibit charge/orbital order driven ferroelectric polarization below the transition point TCO. Large magnetocapacitance in these systems shows a typical multiferroic behavior even though the ferroelectric polarization is small in comparison to that of other ferroelectrics

395

Environmental radiation effects in ULSI devices and electronic systems  

CERN Document Server

A practical guide on how mathematical approaches can be used to analyze and control radiation effects in semiconductor devices within various environments Covers faults in ULSI devices to failures in electronic systems caused by a wide variety of radiation fields, including electrons, alpha -rays, muons, gamma rays, neutrons and heavy ions. Readers will learn the environmental radiation features at the ground or avionics altitude. Readers will also learn how to make numerical models from physical insight and what kind of mathematical approaches should be implemented to analyze the radiation effects. A wide variety of mitigation techniques against soft-errors are reviewed and discussed. The author shows how to model sophisticated radiation effects in condensed matter in order to quantify and control them. The book provides the reader with the knowledge on a wide variety of radiation fields and their effects on the electronic devices and systems. It explains how electronic systems including servers and rout...

Ibe, Eishi H.

2015-01-01

396

Evaluation of Pacific white shrimp (Litopenaeus vannamei) health during a superintensive aquaculture growout using NMR-based metabolomics.  

Science.gov (United States)

Success of the shrimp aquaculture industry requires technological advances that increase production and environmental sustainability. Indoor, superintensive, aquaculture systems are being developed that permit year-round production of farmed shrimp at high densities. These systems are intended to overcome problems of disease susceptibility and of water quality issues from waste products, by operating as essentially closed systems that promote beneficial microbial communities (biofloc). The resulting biofloc can assimilate and detoxify wastes, may provide nutrition for the farmed organisms resulting in improved growth, and may aid in reducing disease initiated from external sources. Nuclear magnetic resonance (NMR)-based metabolomic techniques were used to assess shrimp health during a full growout cycle from the nursery phase through harvest in a minimal-exchange, superintensive, biofloc system. Aberrant shrimp metabolomes were detected from a spike in total ammonia nitrogen in the nursery, from a reduced feeding period that was a consequence of surface scum build-up in the raceway, and from the stocking transition from the nursery to the growout raceway. The biochemical changes in the shrimp that were induced by the stressors were essential for survival and included nitrogen detoxification and energy conservation mechanisms. Inosine and trehalose may be general biomarkers of stress in Litopenaeus vannamei. This study demonstrates one aspect of the practicality of using NMR-based metabolomics to enhance the aquaculture industry by providing physiological insight into common environmental stresses that may limit growth or better explain reduced survival and production. PMID:23555690

Schock, Tracey B; Duke, Jessica; Goodson, Abby; Weldon, Daryl; Brunson, Jeff; Leffler, John W; Bearden, Daniel W

2013-01-01

397

Electron transfer processes in photosynthetics biological systems  

International Nuclear Information System (INIS)

This seminar presents a conceptual model of the sequence of primary light induced electron transfer (ET) steps in photosynthetic bacteria. The temperature dependence of some of these redox reactions, like ET process between cytochrome and bacteriochlorophyll in Chromatium, is characterized by a temperature-independent rate at low temperatures and exhibits the Arrhenius-type dependence at high temperatures. The other primary ET processes, like an ET reaction between bacteriopheophytin and Fe-quinone complex in Rps. spheroides, are temperature-independent in the broad range of 4-300K. The third type of ET processes, exemplified by back ET reactions between Fe-quinone and bacteriochlorophyll in Rhs. rubrum, exhibits negative activation energy at high temperatures. The theoretical approach, describing the primary ET processes in photosynthesis, is based on the non-adiabatic multiphonon ET theory, which incorporates both a continuous distribution of optical phonons in a polar solvent and discrete intramolecular vibrational modes. The last two types of the redox reactions are attributed to activationless ET processes which play an essential role in highly efficient charge separation in primary photosynthetic processes. The transition temperature, separating the tunneling region from the activated region indicates the range of phonon frequencies involved in the ET process. Comparing the low-temperature rates with calculated Franck-Condon factors one can determine the value ondon factors one can determine the value of the electron-exchange matrix element, which in turn provides a rough estimate of the distance scale between a donor and an acceptor in the primary ET events

398

Data Acquisition System for Electron Energy Loss Coincident Spectrometers  

International Nuclear Information System (INIS)

A Data Acquisition System (DAQ) for electron energy loss coincident spectrometers (EELCS) has been developed. The system is composed of a Multiplex Time-Digital Converter (TDC) that measures the flying time of positive and negative ions and a one-dimension position-sensitive detector that records the energy loss of scattering electrons. The experimental data are buffered in a first-in-first-out (FIFO) memory module, then transferred from the FIFO memory to PC by the USB interface. The DAQ system can record the flying time of several ions in one collision, and allows of different data collection modes. The system has been demonstrated at the Electron Energy Loss Coincident Spectrometers at the Laboratory of Atomic and Molecular Physics, USTC. A detail description of the whole system is given and experimental results shown

399

Electron cyclotron emission diagnostic systems for electron temperature perturbation measurement in JT-60U  

International Nuclear Information System (INIS)

Three systems are now operational in JT-60U tokamak for the measurement of electron cyclotron emissions. They are the Fourier transform spectrometer, 20 channels grating polychrometer, and 24 channels heterodyne radiometer. The first system has been absolutely calibrated, and used in the relative calibration of remaining two systems. The paper describes major specifications and recent upgrading of each system. In JT-60U experiments, the heterodyne radiometer system is mainly used for electron temperature perturbations with high signal-to-noise ratio. One of the disadvantage of this system is that the measurement points uniquely determined by the toroidal field, and thus cannot be chosen freely. In the experiment the third system, grating polychrometer, which allows free choice of measurement points, is used to cover the wide cross-section of the JT-60U plasma. (author)

400

Electron cyclotron emission diagnostic systems for electron temperature perturbation measurement in JT-60U  

Energy Technology Data Exchange (ETDEWEB)

Three systems are now operational in JT-60U tokamak for the measurement of electron cyclotron emissions. They are the Fourier transform spectrometer, 20 channels grating polychrometer, and 24 channels heterodyne radiometer. The first system has been absolutely calibrated, and used in the relative calibration of remaining two systems. The paper describes major specifications and recent upgrading of each system. In JT-60U experiments, the heterodyne radiometer system is mainly used for electron temperature perturbations with high signal-to-noise ratio. One of the disadvantage of this system is that the measurement points uniquely determined by the toroidal field, and thus cannot be chosen freely. In the experiment the third system, grating polychrometer, which allows free choice of measurement points, is used to cover the wide cross-section of the JT-60U plasma. (author)

Isayama, Akihiko; Isei, Nobuaki; Ishida, Shinichi; Sato, Minoru [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

2000-03-01

401

36 CFR 1236.26 - What actions must agencies take to maintain electronic information systems?  

Science.gov (United States)

...take to maintain electronic information systems? 1236.26 Section 1236...take to maintain electronic information systems? (a) Agencies must maintain inventories of electronic information systems and review the...

2010-07-01

402

75 FR 448 - In the Matter of: Certain Authentication Systems, Including Software and Handheld Electronic...  

Science.gov (United States)

...Authentication Systems, Including Software and Handheld Electronic Devices...authentication systems, including software and handheld electronic devices...authentication systems, including software and handheld electronic devices...than 20 days after the date of service by the Commission of the...

2010-01-05

403

Integrated freshwater aquaculture, crop and livestock production in the Mekong delta, Vietnam: Determinants and the role of the pond  

OpenAIRE

Promotion of integrated aquaculture with agriculture, including crops and livestock (IAA-farming), requires consideration of both bio-physical and socio-economic contexts. The major factors influencing the adoption of IAA-farming by households at three sites in the Mekong delta were identified. Special attention was given to the multiple roles ponds play in IAA-farming systems. Information was collected through semi-structured interviews and discussions with focus groups and key individuals. ...

Nhan, D. K.; Phong, L. T.; Verdegem, M. C. J.; Duong, L. T.; Bosma, R. H.; Little, D. C.

2007-01-01

404

Passive reactor cooling system [electronic resource  

International Nuclear Information System (INIS)

A nuclear reactor cooling system with passive cooling capabilities operable during a reactor shutdown event without available electric power. In one embodiment, the system includes a reactor vessel with nuclear fuel core and a steam generator fluidly coupled thereto. Primary coolant circulates in a flow loop between the reactor vessel and steam generator to heat secondary coolant in the steam generator producing steam. The steam flows to a heat exchanger containing an inventory of cooling water in which a submerged tube bundle is immersed. The steam is condensed in the heat exchanger and returned to the steam generator forming a closed flow loop in which the secondary coolant flow is driven by natural gravity via changes in density from the heating and cooling cycles. In other embodiments, the cooling system is configured to extract and cool the primary coolant directly using the submerged tube bundle heat exchanger.

405

The integration of cryogenic cooling systems with superconducting electronic systems  

International Nuclear Information System (INIS)

The need for cryogenic cooling has been critical issue that has kept superconducting electronic devices from reaching the market place. Even though the performance of the superconducting circuit is superior to silicon electronics, the requirement for cryogenic cooling has put the superconducting devices at a disadvantage. This report will talk about the various methods for refrigerating superconducting devices. Cryocooler types will be compared for vibration, efficiency, and cost. Some solutions to specific problems of integrating cryocoolers to superconducting devices are presented.

406

The integration of cryogenic cooling systems with superconducting electronic systems  

Energy Technology Data Exchange (ETDEWEB)

The need for cryogenic cooling has been critical issue that has kept superconducting electronic devices from reaching the market place. Even though the performance of the superconducting circuit is superior to silicon electronics, the requirement for cryogenic cooling has put the superconducting devices at a disadvantage. This report will talk about the various methods for refrigerating superconducting devices. Cryocooler types will be compared for vibration, efficiency, and cost. Some solutions to specific problems of integrating cryocoolers to superconducting devices are presented.

Green, Michael A.

2003-07-01

407

Electronic firing systems and methods for firing a device  

Science.gov (United States)

An electronic firing system comprising a control system, a charging system, an electrical energy storage device, a shock tube firing circuit, a shock tube connector, a blasting cap firing circuit, and a blasting cap connector. The control system controls the charging system, which charges the electrical energy storage device. The control system also controls the shock tube firing circuit and the blasting cap firing circuit. When desired, the control system signals the shock tube firing circuit or blasting cap firing circuit to electrically connect the electrical energy storage device to the shock tube connector or the blasting cap connector respectively.

Frickey, Steven J. (Boise, ID); Svoboda, John M. (Idaho Falls, ID)

2012-04-24

408

Distributed Power Electronics for PV Systems (Presentation)  

Energy Technology Data Exchange (ETDEWEB)

An overview of the benefits and applications of microinverters and DC power optimizers in residential systems. Some conclusions from this report are: (1) The impact of shade is greater than just the area of shade; (2) Additional mismatch losses include panel orientation, panel distribution, inverter voltage window, soiling; (3) Per-module devices can help increase performance, 4-12% or more depending on the system; (4) Value-added benefits (safety, monitoring, reduced design constraints) are helping their adoption; and (5) The residential market is growing rapidly. Efficiency increases, cost reductions are improving market acceptance. Panel integration will further reduce price and installation cost. Reliability remains an unknown.

Deline, C.

2011-12-01

409

Antenna systems and electronic warfare applications  

CERN Document Server

This comprehensive book serves as a one-stop resource for practical EW antenna system know-how. Supported with over 700 illustrations and nearly 1,700 equations, this authoritative reference offers you detailed explanations of all the important foundations and aspects of this technology. Moreover, you get an in-depth treatment of a wide range of antenna system applications. The book presents the key characteristics of each type of antenna, including dipoles, monopoles, loops, arrays, horns, and patches. This authoritative volume enables you to analyze and design broadband communication and rad

Poisel, Richard

2012-01-01

410

Multi-electron beam system for high resolution electron beam induced deposition:  

OpenAIRE

The development of a multi-electron beam system is described which is dedicated for electron beam induced deposition (EBID) with sub-10 nm resolution. EBID is a promising mask-less nanolithography technique which has the potential to become a viable technique for the fabrication of 20-2 nm structures after 2013, as described by the International Technology Roadmap for Semiconductors (ITRS), or can be used for rapid prototyping in research applications. The key point is to combine the throughp...

Bruggen, Mattheus Johannes

2008-01-01

411

Magnetic Order in Kondo-Lattice Systems due to Electron-Electron Interactions  

OpenAIRE

The hyperfine interaction between the electron spin and the nuclear spins is one of the main sources of decoherence for spin qubits when the nuclear spins are disordered. An ordering of the latter largely suppresses this source of decoherence. Here we show that such an ordering can occur through a thermodynamic phase transition in two-dimensional (2D) Kondo-lattice type systems. We specifically focus on nuclear spins embedded in a 2D electron gas. The nuclear spins interact ...

Braunecker, Bernd; Simon, Pascal; Loss, Daniel

2008-01-01

412

Electronic Energy Transfer: Localized Operator Partitioning of Electronic Energy in Composite Quantum Systems  

OpenAIRE

A Hamiltonian based approach using spatially localized projection operators is introduced to give precise meaning to the chemically intuitive idea of the electronic energy on a quantum subsystem. This definition facilitates the study of electronic energy transfer in arbitrarily coupled quantum systems. In particular, the decomposition scheme can be applied to molecular components that are strongly interacting (with significant orbital overlap) as well as to isolated fragment...

Khan, Yaser R.; Brumer, Paul

2012-01-01

413

Self-consistent Coulomb picture of an electron-electron bilayer system  

OpenAIRE

In this work we implement the self-consistent Thomas-Fermi approach and a local conductivity model to an electron-electron bilayer system. The presence of an incompressible strip, originating from screening calculations at the top (or bottom) layer is considered as a source of an external potential fluctuation to the bottom (or top) layer. This essentially yields modifications to both screening properties and the magneto-transport quantities. The effect of the temperature, i...

Siddiki, A.

2006-01-01

414

NSTAR Ion Propulsion System Power Electronics  

Science.gov (United States)

The NASA Solar Electric Propulsion Technology Application Readiness (NSTAR) program, managed by the Jet Propulsion Laboratory (JPL), is currently developing a high performance, simplified ion propulsion system. This propulsion system, which is throttleable from 0.5- to 2.3-kW output power to the thruster, targets primary propulsion applications for planetary and Earth-space missions and has been baselined as the primary propulsion system for the first New Millennium spacecraft. The NASA Lewis Research Center is responsible for the design and delivery of a breadboard power processing unit (PPU) and an engineering model thruster (EMT) for this system and will manage the contract for the delivery of the flight hardware to JPL. The PPU requirements, which dictate a mass of less than 12 kg with an efficiency of 0.9 or greater at a 2.3-kW output, forced a departure from the state-of-the-art ion thruster PPU design. Several innovations--including dual-use topologies, simplified thruster control, and the use of ferrite magnetic materials--were necessary to meet these requirements.

1996-01-01

415

Review of power electronics for kinetic energy harvesting systems  

Science.gov (United States)

In the past decade, there has been a dramatic rise of research in the field of energy harvesting from ambient environment, such as mechanical vibrations and dissipated heat. As a key element connecting the harvester and energy storage element in energy harvesting systems, power electronic interface circuitry has drawn significant interests. Abundant research on the power electronic circuits with functions of voltage regulation, optimal power extraction and damping control for energy harvesting systems has been conducted and reported, together with control algorithms and implementations to achieve these functions. This paper reviews the reported concepts for power electronic interface circuits in kinetic energy harvesting systems, such as electromagnetic and piezoelectric harvesters. Power electronic interface circuit concepts included were grouped in the view of energy scale, power flow direction, functionality and complexity. An overview of the power electronic circuit topologies with various functions available for constructing the power electronic interface circuits and problems yet to be solved for kinetic energy harvesting systems is provided by this paper.

Li, Peng; Zhang, Chongxiao; Zuo, Lei

2013-04-01

416

An electron-beam charge neutralization system for ion implanters  

Science.gov (United States)

A new wafer-charge neutralization system which employs a curved solenoid magnetic guiding field and a large-area LaB 6 cathode is described. This system generates a directed beam of low-energy electrons with total current of about 100 mA. The majority of the electrons that impinge on the wafer surface have energies less than 10 eV. This neutralization system is simple and compact, and could be easily incorporated into the existing high-current ion implanters.

Leung, K. N.; Gordon, K. C.; Kunkel, W. B.; McKenna, C. M.; Walther, S. R.; Williams, M. D.

1991-04-01

417

Electronic Health Record A Systems Analysis of the Medications Domain  

CERN Document Server

An accessible primer, Electronic Health Record: A Systems Analysis of the Medications Domain introduces the tools and methodology of Structured Systems Analysis as well as the nuances of the Medications domain. The first part of the book provides a top-down decomposition along two main paths: data in motion--workflows, processes, activities, and tasks in parallel to the analysis of data at rest--database structures, conceptual, logical models, and entities relationship diagrams. Structured systems analysis methodology and tools are applied to: electronic prescription, computerized physician or

Scarlat, Alexander

2012-01-01

418

National electronic medical records integration on cloud computing system.  

Science.gov (United States)

Few Healthcare providers have an advanced level of Electronic Medical Record (EMR) adoption. Others have a low level and most have no EMR at all. Cloud computing technology is a new emerging technology that has been used in other industry and showed a great success. Despite the great features of Cloud computing, they haven't been utilized fairly yet in healthcare industry. This study presents an innovative Healthcare Cloud Computing system for Integrating Electronic Health Record (EHR). The proposed Cloud system applies the Cloud Computing technology on EHR system, to present a comprehensive EHR integrated environment. PMID:23920993

Mirza, Hebah; El-Masri, Samir

2013-01-01

419

Development of Electronic Data Processing /EDP/ augmented management system  

Science.gov (United States)

To tailor the existing Unified Flight Analysis System to management data rather than technical data, a pilot model could be produced in breadboard form, using electronic data processing, in a matter of a few months at very moderate cost. Such a system lends itself to continuous refinement.

Scott, J. E.; Waddleton, T. R.

1968-01-01

420

Development of the electron gun control system for LEBRA  

International Nuclear Information System (INIS)

The control system of the electron gun was replaced at LEBRA. This system was developed using EPICS. EPICS is de-fact standard control framework. Device Support for the high voltage station controller and high frequency grid pulser was developed. (author)

421

Teaching Case: Analysis of an Electronic Voting System  

Science.gov (United States)

This teaching case discusses the analysis of an electronic voting system. The development of the case was motivated by research into information security and management, but as it includes procedural aspects, organizational structure and personnel, it is a suitable basis for all aspects of systems analysis, planning and design tasks. The material…

Thompson, Nik; Toohey, Danny

2014-01-01

422

On the thermodynamics of strongly correlated integrable electron systems  

CERN Document Server

We reexamine the Yang-Yang-Takahashi method of deriving the thermodynamic Bethe ansatz equations which describe strongly correlated electron systems of fundamental physical interest, such as the Hubbard, $s-d$ exchange (Kondo) and Anderson models. It is shown that these equations contain some additional terms which may play an important role in the physics of the systems.

Rupasov, V I

1999-01-01

423

A set of dosimetry systems for electron beam irradiation  

International Nuclear Information System (INIS)

To follow the rapid development of radiation processing with electron beams, it is urgent to set up a set of dosimetric standards to provide Quality Assurance (QA) of electron beam irradiation and unify the values of the quality of the absorbed dose measurements for electron beams. This report introduces a set of dosimetry systems established in Radiometrology Center of China Institute of Atomic Energy (RCCIAE), which have been or will be used as dosimetric standards in the Nuclear Industry System (NIS) in China. For instance, the potassium (silver) dichromate and ceric-cerous sulfate dosimetry systems will be used as standard dosimeters, while alanine-ESR dosimetry system as a transfer dosimeter, and FJL-01 CTA as a routine dosimeter. (author)

424

Data transmission by ship electronic reporting in the RIS system  

Science.gov (United States)

This article presents normative-legal conditions and the principles of navigational data transmission by ship electronic reporting in the RIS (River Information Services) system. The principles of co-operation between the RIS System Management Centre and an inland VTS station are defined. Standards of the navigational data transmission: EDIFAC, ERIMAN, ebXML, BERMAN, eDocs and BICS 2.0 are presented. In this article the structure of the ERI(Electronic Reporting International) messages in electronic reporting for inland navigation are defined. The procedures of introducing changes in reference tables and XML schema is analyzed. Technical guidelines concerning planning, implementation and operational use of RIS on inland waterways are presented. Guidance for the protection of data and a code of conduct for electronic reporting is analyzed. The technical specifications of the message standards for the ship masters are defined.

Lisaj, A.

2009-04-01

425

How is shrimp aquaculture transforming coastal livelihoods and lagoons in Estero Real, Nicaragua? The need to integrate social-ecological research and ecosystem-based approaches.  

Science.gov (United States)

Ecosystem-based approaches to aquaculture integrate environmental concerns into planning. Social-ecological systems research can improve this approach by explicitly relating ecological and social dynamics of change at multiple scales. Doing so requires not only addressing direct effects of aquaculture but also considering indirect factors such as changes in livelihood strategies, governance dynamics, and power relations. We selected the community of Puerto Morazán, Nicaragua as a case study to demonstrate how the introduction of small-scale aquaculture radically transformed another key livelihood activity, lagoon shrimp fishing, and the effects that these changes have had on lagoons and the people that depend on them. We find that shrimp aquaculture played a key role in the collapse, in the 1990s, of an existing lagoon common-property management. Shrimp aquaculture-related capital enabled the adoption of a new fishing technique that not only degraded lagoons but also led to their gradual privatization. The existence of social ties between small-scale shrimp farmers and other community members mitigated the impacts of privatization, illustrating the importance of social capital. Since 2008, community members are seeking to communally manage the lagoons once again, in response to degraded environmental conditions and a consolidation of the shrimp industry at the expense of smaller actors. This research shows that shrimp aquaculture intersects with a complex set of drivers, affecting not only how ecosystems are managed but also how they are perceived and valued. Understanding these social-ecological dynamics is essential to implement realistic policies and management of mangrove ecosystems and address the needs of resource-dependent people. PMID:24912580

Benessaiah, Karina; Sengupta, Raja

2014-08-01

426

Dinámica del Carbono en estanques de peces / Carbon dynamics in aquaculture ponds  

Scientific Electronic Library Online (English)

Full Text Available SciELO Colombia | Language: Spanish Abstract in spanish En la dinámica del carbono en estanques dedicados a la piscicultura intervienen actividades físicas, químicas y biológicas las cuales transforman el carbono agregado en forma de alimento o de fertilizaciones orgánicas e inorgánicas. La intensificación de la producción de peces, está acompañada del i [...] ncremento de las entradas de carbono, en forma de alimento. Estas entradas, han excedido la capacidad metabólica del estanque lo que en consecuencia ha derivado en la acumulación de compuestos orgánicos y deterioro de la calidad del agua. Algunas investigaciones muestran que la calidad del agua, ha pasado a constituir la principal limitante en la búsqueda de una mayor intensificación de la producción piscícola. La mayor salida de carbono del sistema productivo está asociada con la evasión gaseosa en forma de CO2, situación que ubica a los sistemas productivos no como sumideros sino como generadores de huella de carbono. El principal medio de retención del CO2 en los estanques de peces, es el fitoplancton. En términos generales el balance de carbono en los sistemas productivos acuícolas es positivo, no obstante es posible lograr una mayor recuperación siendo necesario realizar ajustes a las prácticas de manejo y profundizar en la investigación de la dinámica del mismo. Entre los factores que inciden en la dinámica del Carbono en estanques están las características del alimento y las prácticas de alimentación, la especie cultivada, el recambio de agua, la aireación, la profundidad del estanque y los microorganismos presentes. Abstract in english Aquaculture ponds'carbon dynamicsare dominated by physical, chemical and biological transformations in feed and organic and inorganic fertilisation. Increasedfish productionhas been associated with an increase incarbon inputin the form of fish-feed exceeding ponds'metabolic capacity,thereby leading [...] to water quality deteriorating due toan accumulationof organic compounds. Water quality is a major constraint in terms of increasedfish crop density. The most important carbon loss within aproduction system is associated with CO2evaporation;this makes aquaculture ponds become carbon footprints instead of carbon sinks. Phytoplankton is the major means of CO2 retentionas it captures both that produced by the respiration of all organisms within a particularpond and within the atmosphere. Aquaculture production systemsusually have a negativeorganic carbon balance; however,higher carbon recovery is possible but this involves adjusting management practiceand increasedresearch into the pertinent dynamics. Feed, feedingpractices, the speciesbeing cultivated, water exchange, aeration, pond depth and the microorganisms living in a pondare factorswhich affect the biogeochemical carboncycle in aquaculture ponds.

Guillermo, Ladino-Orjuela.

2011-06-01

427

International Conference on Power Electronics and Renewable Energy Systems  

CERN Document Server

The book is a collection of high-quality peer-reviewed research papers presented in Proceedings of International Conference on Power Electronics and Renewable Energy Systems (ICPERES 2014) held at Rajalakshmi Engineering College, Chennai, India. These research papers provide the latest developments in the broad area of Power Electronics and Renewable Energy. The book discusses wide variety of industrial, engineering and scientific applications of the emerging techniques. It presents invited papers from the inventors/originators of new applications and advanced technologies.

Suresh, L; Dash, Subhransu; Panigrahi, Bijaya

2015-01-01

428

Automated averaging techniques for power electronic-based systems  

OpenAIRE

Average-value models are commonly used in the design and analysis of power electronic based systems. There are numerous averaging methodologies that have been developed that are applicable to specific classes of power electronic circuits including state-space averaging, canonical cell averaging, switch averaging, sampled-data modeling, and multi-rate averaging. Historically, the development of each averaging technique and the extensions thereof was motivated by a specific converter topology f...

Walters, Eric Allen

1999-01-01

429

Photoelectrochemical solar conversion systems molecular and electronic aspects  

CERN Document Server

Providing new insights into the molecular and electronic processes involved in the conversion of sunlight into chemical products, Photoelectrochemical Solar Conversion Systems: Molecular and Electronic Aspects begins with an historical overview and a survey of recent developments in the electrochemistry of semiconductors and spectroscopic techniques. It then provides a comprehensive introduction to the science of conversion cells, reviews current issues and potential directions, and covers a wide range of materials from organic to inorganic cells.Employing a tutorial organization with balanced

Munoz, Andres G

2012-01-01

430

Improvements in the electron gun system for higher voltage  

International Nuclear Information System (INIS)

In the PF linac we must accelerate high current beams for the KEK B-Factory. The electron gun system was improved for higher voltage (200 kV) in order both to increase emission current and to decrease space charge effects. We newly manufactured the electron gun, the pulse transformer, and the gun-pulser pulse forming network. They are now under stable operation. (author)

431

Electronic money model implementation in standard and limited arithmetics systems  

OpenAIRE

As mobile phones and technology advance new opportunities for implementation of elektronic money systems become possible. Electronic money is one of the latest methods for paying for goods and there are just a few implementations. In this work implementation of Stefan Brands electronic money model was performed. Stefan Brands protocol was implemented using Java langauge in standard computer and in mobile phone. Efficiency of these implementations was estimated and it was found that implementa...

Palevic?ius, Paulius

2013-01-01

432

Electronic realization of the fractional-order systems  

Directory of Open Access Journals (Sweden)

Full Text Available This article is devoted to the electronic (analogue realization of the fractional-order systems – controllers or controlled objects whose we earlier used, identified, and analyzed as a mathematical models only ??? namely a fractional-order differential equation, and solved numerically using a method based on the truncated version of the Grunwald - Letnikov formula for fractional derivative. The electronic realization of the fractional derivative is based on the continued fraction expansion of the rational approximation of the fractional differentiator from which we obtained the values of the resistors and capacitors of the electronic circuit. Along with the mathematical description are presented also simulation and measurement results.

Františka Dor?áková

2007-10-01

433

Positive safety electronic control system and process  

International Nuclear Information System (INIS)

The control process described is for a protection system, particularly of a nuclear reactor, according to which, as from N measurements of one or several physical values measurements are processed by N adaptation members and/or calculations. The median value is selected of the N signals corresponding to N determinations, and the median value is compared with a reference value so that this comparison initiates the triggering off of the desired protective action. This process can be used to carry out the emergency shutdown of a nuclear reactor by dropping safety absorbers into the core

434

Design of automatic tracking system for electron beam welding  

International Nuclear Information System (INIS)

The design and experimental process of an automatic tracking system applied to local vacuum electron beam welding are dealt with in this paper. When the annular parts of an exactitude apparatus were welded, the centre of rotation of the electron gun and the centre of the annular weld are usually not superposed because of the machining error, workpiece's setting error and so on. In this teaching process, a little bundle of electron beam is used to scan the weld groove, the amount of the secondary electrons reflected from the workpiece is different when the electron beam scans the both sides and the centre of the weld groove. The difference can indicate the position of the weld and then a computer will record the deviation between the electron beam spot and the centre of the weld groove. The computer will analyze the data and put the data into the storage software. During the welding process, the computer will modify the position of the electron gun based on the deviation to make the electron beam spot centered on the annular weld groove. (authors)

435

The dynamics of highly excited electronic systems: Applications of the electron force field  

Science.gov (United States)

Highly excited heterogeneous complex materials are essential elements of important processes, ranging from inertial confinement fusion to semiconductor device fabrication. Understanding the dynamics of these systems has been challenging because of the difficulty in extracting mechanistic information from either experiment or theory. We describe here the electron force field (eFF) approximation to quantum mechanics which provides a practical approach to simulating the dynamics of such systems. eFF includes all the normal electrostatic interactions between electrons and nuclei and the normal quantum mechanical description of kinetic energy for the electrons, but contains two severe approximations: first, the individual electrons are represented as floating Gaussian wave packets whose position and size respond instantaneously to various forces during the dynamics; and second, these wave packets are combined into a many-body wave function as a Hartree product without explicit antisymmetrization. The Pauli principle is accounted for by adding an extra spin-dependent term to the Hamiltonian. These approximations are a logical extension of existing approaches to simulate the dynamics of fermions, which we review. In this paper, we discuss the details of the equations of motion and potentials that form eFF, and evaluate the ability of eFF to describe ground-state systems containing covalent, ionic, multicenter, and/or metallic bonds. We also summarize two eFF calculations previously reported on electronically excited systems: (1) the thermodynamics of hydrogen compressed up to ten times liquid density and heated up to 200 000 K; and (2) the dynamics of Auger fragmentation in a diamond nanoparticle, where hundreds of electron volts of excitation energy are dissipated over tens of femtoseconds. These cases represent the first steps toward using eFF to model highly excited electronic processes in complex materials.

Su, Julius T.; Goddard, William A.

2009-12-01

436

2D electron systems viewed through an RF spectrometer  

International Nuclear Information System (INIS)

Electrons trapped at the liquid helium-vacuum interface are an almost ideal realization of a 2D electron