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Sample records for aquaculture system electronic

  1. PECONIC BAY SYSTEM AQUACULTURE

    PECONIC BAY SYSTEM AQUACULTURE This reference document serves as the aquaculture sub-section for Phase II of a four-phase series of economic studies being conducted by Economic Analysis, Inc., for the Peconic Estuary Program. It provides an evaluation of the history, current stat...

  2. Partitioned aquaculture systems

    Conventional aquaculture ponds provide a number of ecological services supporting fish and shellfish production. The pond provides confinement space for the aquatic organisms, while algal growth in the pond serves as the base of an aquatic food chain providing some or all of the feed, depending on p...

  3. Aquaculture Thesaurus: Descriptors Used in the National Aquaculture Information System.

    Lanier, James A.; And Others

    This document provides a listing of descriptors used in the National Aquaculture Information System (NAIS), a computer information storage and retrieval system on marine, brackish, and freshwater organisms. Included are an explanation of how to use the document, subject index terms, and a brief bibliography of the literature used in developing the…

  4. Prospective Analysis of the Aquaculture Sector in the EU. PART 2: Characterisation of Emerging Aquaculture Systems

    STURROCK Helen; Newton, Richard; PAFFRATH Susan; Bostock, John; MUIR James; Young, James; IMMINK Anton; DICKSON Malcolm

    2008-01-01

    This report is based on the outcome of the study on "Prospective analysis of the aquaculture sector in the EU", launched and coordinated by the JRC (IPTS) and carried out by the University of Stirling. The report consists of two parts: 1) "Prospective analysis of the aquaculture sector in the EU ¿ Part 1: Synthesis report", and 2) "Prospective analysis of the aquaculture sector in the EU ¿ Part 2: Characterisation of emerging aquaculture systems." This second report is concerned wit...

  5. Optimization of aquaculture systems in Spain

    Izquierdo, M. [Instituto Ciencias de la Construccion Eduardo Torroja, Madrid (Spain); Carrillo, M. [Instituto de Acuicultura de Torre la Sal, Castellon (Spain)

    1997-12-31

    An analysis of present heat production systems, using fossil fuel combustion, employed for sea water heating in Spanish hatcheries is given in this paper and compared to a technical solution based on the employment of a heat pump. Price per unit of produced energy is calculated for each system using liquid and gaseous fuels, and then these prices are compared to the price obtained for a heat pump. The heat pump system is also compared, from the point of view of its precision in maintaining temperatures, to the systems used at the present. A project prototype for thermal conditioning and temperature control in aquaculture rearing tanks is described. (author)

  6. Does aquaculture add resilience to the global food system?

    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

    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

  7. In-tank aeration, a necessary compliment of loaded systems in an airlift recirculating aquaculture system

    Water treatment components in recirculating aquaculture systems in generally address solids removal, nitrification, circulation, aeration, and degasification. Airlift pumps in a recirculating aquaculture system can address water circulation, aeration, and degasification. Recent data indicates oxygen...

  8. The potential of periphyton-based aquaculture production systems

    Ul Azim, M.E.

    2001-01-01

    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 t...

  9. Assessment of a closed greenhouse aquaculture and hydroponic system

    Head, W.D.

    1984-01-01

    Research was conducted to address three objectives: 1) to determine the nitrogen cycling of a closed greenhouse aquaculture and hydroponic system; 2) to determine the energy budget of a closed greenhouse aquaculture and hydroponic system; and 3) to determine which low cost fish diets could be used as a replacement or supplement to commercial diets for Tilapia mossambica. A 6435 liter recirculating aquaculture system was enclosed in a 32.6 m/sup 2/ greenhouse. Water was recirculated through two 416 liter trickling filter towers and three 5.5 m long hydroponic troughs. The aquaculture tank was stocked with a polyculture of channel catfish (Ictalurus punctatus) and tilapia (Tilapia mossambica) and the hydroponic troughs were planted with tomatoes (Lycopersicon esculentum). The fishes were fed a commercial fish diet and the tomatoes were irrigated with the aquaculture water using a modified Nutrient Film Technique. The fish yield was 42.2 kg and the average tomato yield from 24 plants was 4.1 kg/plant. The combined fish and tomato production accounted for 65% of the total nitrogen input. Leaf analyses and visual inspection showed that the tomato plants from the hydroponic troughs were deficient in potassium and magnesium. An energy analysis of the greenhouse and aquaculture-hydroponic system showed that when combining the energy outputs of heat, fish, and tomatoes the energy ratio (energy output/energy input) was similar to literature values for milkfish pond culture. When only the fish production was considered the energy ratio was similar to literature values reported for intensive water recirculating systems.

  10. Low-head saltwater recirculating aquaculture systems utilized for juvenile red drum production

    Recirculating aquaculture systems reuse water with mechanical and biological treatment between each use and thus require wastewater treatment techniques for continuous waste removal. However, the traditional techniques and equipment utilized in recirculating aquaculture systems are expensive. The d...

  11. Microscreen effects on water quality in replicated recirculating aquaculture systems

    Fernandes, Paulo; Pedersen, Lars-Flemming; Pedersen, Per Bovbjerg

    2015-01-01

    This study investigated the effects of three microscreen mesh sizes (100, 60 and 20 μm) 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...

  12. ECONOMIC ASSESSMENT OF WASTE WATER AQUACULTURE TREATMENT SYSTEMS

    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 ...

  13. Solar Thermal Aquaculture System Controller Based on Artificial Neural Network

    Doaa M. Atia; Faten H Fahmy; Ninet M Ahmed; Hassen T. Dorrah

    2011-01-01

    Temperature is one of the most principle factors affects aquaculture system. The water temperature is very important parameter for shrimp growth. It can cause stress and mortality or superior environment for growth and reproduction. The required temperature for optimal growth is 34oC, if temperature increase up to 38oC it causes death of the shrimp, so it is important to control water temperature. Solar thermal water heating system is designed to ...

  14. ALTERNATIVE PRACTICE FROM COASTAL POND TO RECIRCULATION AQUACULTURE SYSTEM

    Ludi Parwadani Aji

    2012-02-01

    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.

  15. Ideotyping integrated aquaculture systems to balance soil nutrients

    Johan A. J. Verreth

    2011-12-01

    Full Text Available Due to growing land scarcity and lack of nutrient inputs, African farmers switched from shifting cultivation to continuous cropping and extended crop area by bringing fragile lands such as river banks and hill slopes into production. This accelerated soil fertility decline caused by erosion, harvesting and insufficient nutrient replenishment. We explored the feasibility to reduce nutrient depletion by increasing nutrient utilization efficiencies, while diversifying and increasing food production through the development of integrated aquaculture – agriculture (IAA. Considering the climatic conditions prevailing in Kenyan highlands, aquaculture production scenarios were ideotyped per agro-ecological zone. These aquaculture production scenarios were integrated into existing NUTrient MONitoring (NUTMON farm survey data for the area. The nutrient balances and flows of the resulting IAA-systems were compared to present land use. The effects of IAA development on nutrient depletion and total food production were evaluated. With the development of IAA systems, nutrient depletion rates dropped by 23–35%, agricultural production increased by 2–26% and overall farm food production increased by 22–70%. The study demonstrates that from a bio-physical point of view, the development of IAA-systems in Africa is technically possible and could raise soil fertility and total farm production. Further studies that evaluate the economic feasibility and impacts on the livelihood of farming households are recommended.

  16. Solid waste reduction of closed recirculated aquaculture systems by secondary culture of detritivorous organisms

    Bischoff, Adrian A.

    2007-01-01

    Conventional production systems used in aquaculture such as ponds, raceways, net cages or recirculating systems have in common that they release large amounts of feed nutrients either in dissolved or particulate form. The efficient removal of suspended solids is a key factor for the successful operation of recirculating aquaculture systems (RAS). The here presented thesis utilised the solid wastes from modern aquaculture recirculating system for carnivorous fish for the secondary production o...

  17. Control methodologies based on geothermal recirculating aquaculture system

    One of the most common uses of geothermal heat is in RAS (recirculation aquaculture systems) where the water temperature is accurately controlled for optimum growing conditions for sustainable and intensive rearing of marine and freshwater fish. This paper presents a design for RAS rearing tank and plate type heat exchanger to be used with geothermal energy as a source of heating water. A well at Umm Huweitat on the Red Sea is used as a source of geothermal energy. The heat losses from the RAS tank are calculated using Geo Heat Center Software. Then a plate type heat exchanger is designed using the epsilon–NTU (number of transfer units) analysis method. For optimal growth and abundance of production, a different techniques of control system are applied to control the water temperature. The total system is built in MATLAB/SIMULINK to study the overall performance of control unit. Finally, a comparison between PI, Fuzzy-PID, and Fuzzy Logic Control has been done. - Highlights: • Design recirculating aquaculture system using geothermal energy. • Design a PI controller for water temperature control. • Design a Fuzzy logic controller for water temperature control. • Design a Fuzzy-PID controller for water temperature control. • Comparison between different control systems

  18. Solar energy system design for a lobster aquaculture facility

    1977-09-30

    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.

  19. Exergetic performance analysis of a recirculating aquaculture system

    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.

  20. Tracing dissolved organic matter (DOM) from land-based aquaculture systems in North Patagonian streams.

    Nimptsch, Jorge; Woelfl, Stefan; Osorio, Sebastian; Valenzuela, Jose; Ebersbach, Paul; von Tuempling, Wolf; Palma, Rodrigo; Encina, Francisco; Figueroa, David; Kamjunke, Norbert; Graeber, Daniel

    2015-12-15

    Chile is the second largest producer of salmonids worldwide. The first step in the production of salmonids takes place in land-based aquacultures. However, the effects of the discharge from these aquacultures on stream dissolved organic matter (DOM) content, molecular composition and degradability are unknown. The aim of this study was thus to investigate the inputs of anthropogenic DOM from land-based aquaculture to the predominantly pristine river systems of North Patagonia. We hypothesized, that i) DOM exported from land-based aquaculture mainly consists of protein-like fluorescence (tyrosine and tryptophan) released from fish feces and food remains, and that ii) this DOM is highly degradable and therefore rapidly turned-over within the receiving streams. In the North Patagonian region we conducted a screening of ten land-based aquacultures and an intensive sampling campaign for one aquaculture. This was combined with longitudinal transects and a degradation experiment in order to couple the composition of DOM exported from land-based aquacultures to its degradability in streams. We measured dissolved organic carbon (DOC) concentration by high-temperature catalytic oxidation and DOM composition by fluorescence spectroscopy and parallel factor analysis. In the effluent of the ten screened aquacultures and in the repeated sampling of one aquaculture, we consistently found an increase of DOC concentrations and a dominance of protein-like fluorescence. The protein-like fluorescence rapidly disappeared downstream of the aquacultures, and in the degradation experiment. 21% of the DOC export from the repeatedly sampled aquaculture resulted from food addition and 76% from fish production. We conclude that large amounts of degradable DOM are exported from land-based aquacultures. This probably has strong effects on the ecological structure and function of North Patagonian streams, and similarly affected streams worldwide. PMID:26282747

  1. Modeling of TAN in recirculating aquaculture systems by AQUASIM

    Arvin, Erik; Pedersen, Lars-Flemming

    2011-01-01

    Modeling of total ammonium nitrogen (TAN) in recirculating aquaculture systems (RAS) contribute to identifying and quantifying the most important processes and their relative contribution to removal of TAN. AQUASIM is a flexible modular simulation system for water quality in natural and technical...... Hirtshals, Denmark (Pedersen et al., 2009). Water from the fish rearing tank is treated in a sedimentation tank and subsequently by biological treatment in a submerged biofilter and in a trickling filter. Generally, the performance of the biological treatment was very well and average TAN concentrations in...... the RAS were in the range 0.1-0.4 mg TAN/L depending on the cumulative feed load. The average nitrite concentrations were a little higher than the average TAN concentrations, in the range 0.2-0.6 mg N/L. Our TAN model simulated TAN removal by the following processes: 1 & 2: Nitrification in the...

  2. Low-head recirculating aquaculture system for juvenile red drum production

    The USDA Agricultural Research Service and the Center for Aquaculture and Stock Enhancement at Harbor Branch Oceanographic Institute-FAU (HBOI-FAU) are collaborating to evaluate low-head recirculating aquaculture system designs to intensively produce red drum juveniles as part of the Florida Fish an...

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

    A. N.A. Faiz

    2010-01-01

    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.

  4. The evaluation of oxygen and carbon dioxide transfer associated with airlifts in recirculating aquaculture systems

    Airlifts in recirculating aquaculture systems (RAS) provide aeration, degasification, and water circulation. They allow the simplification of systems, and if designed properly, can reduce the capital costs and minimize operation and maintenance associated with alternative pumping systems. In order t...

  5. Effect of Wind-solar Complementary Increasing Oxygen System in Aquaculture

    Guodong You

    2013-12-01

    Full Text Available In order to explore a sustainable aquaculture methodology, water was increased oxygen by a wind-solar power which was tested in a production period of the Penaeus vannamei in paper. The result shows that, compareing with the conventional aerating comparison, the system could improve water environment in ponds and dissolved oxygen, temperature, pH value and the content of nitrite stably and uniformly change; make full use of wind energy and solar energy clean energy, save 100% on power consumption, 15.9% on bait, 46.0% on drug; save aquaculture costs, increase income 282%. Using "Wind-solar" complementary increasing oxygen can improve water environment, save power, reduce aquaculture costs, increase aquaculture production and income, provide a new thought and method for green and ecological aquaculture, so it has high value of practical application.

  6. Oxygen mass balance in a recirculation aquaculture system for raising European Wels (Silurus glanis L.)

    Mongirdas, Viktoras; Kusta, Albinas

    2006-01-01

    The growth of the European Wels or sheat-fish (Silurus glanis L.) was evaluated in a recirculation aquaculture system situated in a greenhouse. Recirculation aquaculture system components were evaluated in terms of oxygen use and generation. Oxygen gradients revealed the main fault of the originally constructed system elements – mechanical and biological filters. The influence of organic matter accumulation and biofilm formation in the mechanical filter was found to have a strong influence on...

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

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

    2014-01-01

    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 ...... 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....

  8. Microbial communities of recirculating aquaculture facilities: interaction between heterotrophic and autotrophic bacteria and the system itself

    Michaud, Luigi

    2007-01-01

    Les systèmes d'aquaculture en circuit recirculé (Recirculating Aquaculture Systems, RAS) peuvent être considérés comme une alternative à la technologie de l'aquaculture en milieu ouvert et en bassins (en consommant moins d'eau pour un même rendement de production) ou peuvent être intégrés dans une chaîne de production avec des systèmes d'enclos en filet. L'intérêt des RAS est dû à leurs avantages intrinsèques comme la réduction des besoins en surface et en eau, le haut niveau de contrôle e...

  9. New developments in recirculating aquaculture systems in Europe: A perspective on environmental sustainability

    2010-01-01

    The dual objective of sustainable aquaculture, i.e., to produce food while sustaining natural resources is achieved only when production systems with a minimum ecological impact are used. Recirculating aquaculture systems (RASs) provide opportunities to reduce water usage and to improve waste management and nutrient recycling. RAS makes intensive fish production compatible with environmental sustainability. This review aims to summarize the most recent developments within RAS that have contri...

  10. LCA and emergy accounting of aquaculture systems: towards ecological intensification.

    Wilfart, Aurélie; Prudhomme, Jehane; Blancheton, Jean-Paul; Aubin, Joël

    2013-05-30

    An integrated approach is required to optimise fish farming systems by maximising output while minimising their negative environmental impacts. We developed a holistic approach to assess the environmental performances by combining two methods based on energetic and physical flow analysis. Life Cycle Assessment (LCA) is a normalised method that estimates resource use and potential impacts throughout a product's life cycle. Emergy Accounting (EA) refers the amount of energy directly or indirectly required by a product or a service. The combination of these two methods was used to evaluate the environmental impacts of three contrasting fish-farming systems: a farm producing salmon in a recirculating system (RSF), a semi-extensive polyculture pond (PF1) and an extensive polyculture pond (PF2). The RSF system, with a low feed-conversion ratio (FCR = 0.95), had lower environmental impacts per tonne of live fish produced than did the two pond farms, when the effects on climate change, acidification, total cumulative energy demand, land competition and water dependence were considered. However, RSF was clearly disconnected from the surrounding environment and depended highly on external resources (e.g. nutrients, energy). Ponds adequately incorporated renewable natural resources but had higher environmental impacts due to incomplete use of external inputs. This study highlighted key factors necessary for the successful ecological intensification of fish farming, i.e., minimise external inputs, lower the FCR, and increase the use of renewable resources from the surrounding environment. The combination of LCA and EA seems to be a practical approach to address the complexity of optimising biophysical efficiency in aquaculture systems. PMID:23531606

  11. All about Aquaculture.

    Brody, Michael J.; Patterson, B. Patricia

    1992-01-01

    Describes a sequence of activities in which students set up a classroom aquarium to learn about aquaculture. Discusses the aquarium system, filtration and maintenance, adding organisms to the system, technological considerations, aquaculture economics, and political and social aspects of aquaculture. (MDH)

  12. Feasibility of adopting aquaculture without detriment to existing farming practices: a case of Bangladesh farming systems

    Ahmed, M.; Rab, M.A.

    1992-01-01

    Integrating agriculture aquaculture that would draw inputs from on farm sources is viewed as a viable option to improve the productivity, income and resource use efficiency of existing farms in Bangladesh. To assess the existing resource availability, use pattern and efficiency before introducing new aquaculture technology within the existing farm systems, a survey of 330 pond operating farm households was conducted in six selected unions from two thanas (subdistricts) of Bangladesh.

  13. The Usage of Aquatic Floating Macrophytes (Lemna And Wolffia) as Biofilter in Recirculation Aquaculture System (RAS)

    Velichkova, Katia Naneva; Sirakov, Ivaylo Nikolaev

    2013-01-01

    Conventional water treatment in recirculation aquaculture systems (RAS) is a limited technology to answer the challenges of so called "sustainable aquaculture". This is why new and innovative technologies need to be invented and introduced in RAS. The aim of the conducted study was to determine the possible advantages of using two macrophytic plants - Lemna minor and Wolffia arrhiza and their quality as biological filter in a RAS for the cultivation of fingerlings from common ca...

  14. Aquaculture; Acquacoltura

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

    1998-12-01

    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.

  15. Recirculating Systems for Pollution Prevention in Aquaculture Facilities

    Maribel Quezada-Cruz; Gabriela Vázquez-Rodríguez; Elizabeth Contreras-López; Claudia Coronel-Olivares; R. Icela Beltrán-Hernández; Juan Ramírez-Godínez

    2013-01-01

    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 th...

  16. ALTERNATIVE PRACTICE FROM COASTAL POND TO RECIRCULATION AQUACULTURE SYSTEM

    Ludi Parwadani Aji

    2012-01-01

    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, Recirc...

  17. An integrated fish-plankton aquaculture system in brackish water

    Gilles, Sylvain; Fargier, L.; Lazzaro, Xavier; Baras, Etienne; De Wilde, N.; Drakides, C.; Amiel, C.; Rispal, B.; Blancheton, J.P.

    2013-01-01

    Integrated Multi-Trophic Aquaculture takes advantage of the mutualism between some detritivorous fish and phytoplankton. The fish recycle nutrients by consuming live (and dead) algae and provide the inorganic carbon to fuel the growth of live algae. In the meanwhile, algae purify the water and generate the oxygen required by fishes. Such mechanism stabilizes the functioning of an artificially recycling ecosystem, as exemplified by combining the euryhaline tilapia Sarotherodon melanotheron heu...

  18. Description and Improvement of the 'Whedo'-Aquaculture-System in Malanville (North of Benin)

    Hauber, Melanie Erika

    2011-01-01

    This work delves into the recently developed ‘Whedo’-aquaculture-system in the rural community of Malanville (North Benin)and aims on providing a closer insight on this – for the area--recent system including the ecological but also the sociological and economical aspects in order to develop this extensive traditional fishery to a more productive semi-intensive aquaculture system. With the retreat of the flood ‘Whedos’ usually become infested with numerous hydato-and tenagophytes, while the p...

  19. Characterising organic matter in recirculating aquaculture systems with fluorescence EEM spectroscopy

    Hambly, Adam; Arvin, Erik; Pedersen, Lars-Flemming; Pedersen, Per Bovbjerg; Seredynska-Sobecka, Bozena; Stedmon, Colin

    2015-01-01

    The potential of recirculating aquaculture systems (RAS) in the aquaculture industry is increasingly being acknowledged. Along with intensified application, the need to better characterise and understand the accumulated dissolved organic matter (DOM) within these systems increases. Mature RASs......, stocked with rainbow trout and operated at steady state at four feed loadings, were analysed by dissolved organic carbon (DOC) analysis and fluorescence excitation-emission matrix (EEM) spectroscopy. The fluorescence dataset was then decomposed by PARAFAC analysis using the drEEM toolbox. This revealed...

  20. Development of a seaweed species-selection index for successful culture in a seaweed-based integrated aquaculture system

    Kang, Yun Hee; Hwang, Jae Ran; Chung, Ik Kyo; Park, Sang Rul

    2013-03-01

    Integrated multi-trophic aquaculture (IMTA) has been proposed as a concept that combines the cultivation of fed aquaculture species ( e.g., finfish/shrimp) with extractive aquaculture species ( e.g., shellfish/seaweed). In seaweed-based integrated aquaculture, seaweeds have the capacity to reduce the environmental impact of nitrogen-rich effluents on coastal ecosystems. Thus, selection of optimal species for such aquaculture is of great importance. The present study aimed to develop a seaweed species-selection index for selecting suitable species in seaweed-based integrated aquaculture system. The index was synthesized using available literature-based information, reference data, and physiological seaweed experiments to identify and prioritize the desired species. Undaria pinnatifida, Porphyra yezoensis and Ulva compressa scored the highest according to a seaweed-based integrated aquaculture suitability index (SASI). Seaweed species with the highest scores were adjudged to fit the integrated aquaculture systems. Despite the application of this model limited by local aquaculture environment, it is considered to be a useful tool for selecting seaweed species in IMTA.

  1. An evaluation of a micro programmable logic controller for oxygen monitoring and control in tanks of a recirculating aquaculture system

    Control of dissolved gases, especially oxygen is an essential component of recirculating aquaculture systems. The use of pure oxygen in a recirculating aquaculture system creates supersaturated concentrations of dissolved oxygen and can reduce fish production costs by supporting greater fish and fee...

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

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

    2014-01-01

    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...... 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....

  3. Low-dose hydrogen peroxide application in closed recirculating aquaculture systems

    Pedersen, Lars-Flemming; Good, C.; Pedersen, Per Bovbjerg

    2012-01-01

    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...... 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...

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

    Grødal, Jon Arne; Paaske, Frank Gjervik

    2006-01-01

    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 b...

  5. Mass transfer coefficients for carbon dioxide and oxygen for a polygeyser biofilter using airlift in an aquaculture reuse system

    Aquaculture is a rapidly growing industry, accounting for over one-third of all direct fisheries consumption. In recirculating aquaculture systems the primary technology being used is energy intensive because water must be moved continuously through the culture and treatment units to remove wastes ...

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

    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...

  7. Disinfection of water in recirculating aquaculture systems with peracetic acid (PAA)

    The disinfection behaviour of peracetic acid (PAA) in recirculating aquaculture systems (RAS) was investigated. Peracetic acid is a strong oxidizing agent found in various concentrations in different products. Three Wofasteril PAA products (E400 (c), Lspecical; AC 150) were tested in vitro for the...

  8. Practical design and application of airlift technology for aquaculture reuse systems

    Air-lift technology to support water movement in low-head water treatment units for recirculating aquacultures systems provides an energy efficient alternative to the use of centrifugal pumps. The benefits of air-lift are further realized when electrical requirements for aeration, CO2 degassing, and...

  9. Observations on side-swimming rainbow trout Oncorhynchus mykiss in water recirculation aquaculture systems

    During a controlled 6-month study using six replicated water recirculation aquaculture systems (WRAS), it was observed that rainbow trout Oncorhynchus mykiss in all WRAS exhibited a higher-than-normal prevalence of side-swimming (i.e. controlled, forward swimming, but with misaligned orientation suc...

  10. Performance evaluation of pumping systems used in commercial-scale, split-pond aquaculture

    Split-pond aquaculture systems have been adopted widely by United States catfish farmers as a way to improve production performance. The split-pond consists of a fish-culture basin that is connected to a waste-treatment lagoon by two water conveyance structures. Water is circulated between the two b...

  11. Low-dose hydrogen peroxide application in closed recirculating aquaculture systems

    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...

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

    Mandal, Shovon; Mallick, Nirupama

    2012-01-01

    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.

  13. DEVELOPMENT OF SUSTAINABLE INTEGRATED AQUACULTURE SYSTEMS WITH ASSESSMENT OF ENVIRONMENTAL, SOCIAL, AND ECONOMIC IMPLICATIONS

    The successful completion of this project was achieved using a multi-disciplinary approach in the design, testing, and implementation of a re-circulating integrated aquaculture production system. Graduate students were individually selected for this project based on their ex...

  14. Strategies to enhance the competitiveness of semi-intensive aquaculture systems in costal earth ponds: the organic aquaculture approach

    Manuel Sardinha

    2014-06-01

    Full Text Available Earthen ponds are the main production system for European seabass (Dicentrarchus labrax and gilthead seabream (Sparus aurata in Portugal and in Southern Spain. Production costs in this low productivity farming system are higher compared to intensive cage farms, and its economic sustainability depends on product differentiation and optimization of production. The development of new farming protocols, to enhance productivity of ponds and lagoons, or the implementation of certification processes to add value to products from extensive and semi-intensive systems, could render these activities more economics benefits and be attractive for a new generation of farmers. One clear strategy to differentiate and add value to seabream produced in semi-intensive systems is its production under organic standards. Feeds often represent 40-60% of the operational costs of fish farming. In relation to the traditional feeds, the organic certified feeds currently present a price-differential of about +30%. To assess it economic feasibility, it is therefore essential to validate if such higher feeding costs will represent an increase on productivity (fish growth and feed conversion or can be fully integrated in the final sale price. Throughout a full production cycle of gilthead seabream (from 9 grams until >350 grams, a series of trials allowed us to assess the effects of: a an organic certified feed; b variable feeding levels (100 and 80% of recommendations; and c culture density (0.5 and 1.0 kg/m3 on the overall growth performance, body composition and environmental impact at the fish farm level. Results show that growth performance (weight gain and feed conversion ratio of seabream fed the organic feed was similar to that found in fish fed a traditional diet. With the organic feed, a reduction of the feeding level by 20% of the manufacturer recommendations led to a lower growth, while a similar reduction on the feeding level of the traditional feed had no impact on the performance of seabream. Lower culture density (0.5 kg/m3 resulted in higher overall growth performance. The impact, in terms of nitrogenous (N and phosphorus (P loads, among the various scenarios were calculated and clearly reinforce the environmental sustainability of these semi-intensive production systems. The use of organic feeds does not lead to a significant enhancement of the growth performance. Therefore, the additional costs associated to feeding under organic standards, need to be incorporated in the sale price, thus requiring a targeted and differentiated marketing and distribution approach. Sociedade Piscicultura Farense Lda, as other traditional aquacultures depends on the enhancement of the natural environment, combined with production fine-tuning and product positioning, rewarding the quality of the final product. The positive effects of extensive and semi-intensive aquaculture in coastal areas, including environmental protection and restoration in areas of particular ecological interest, employment opportunity and development in rural and coastal areas are highly appealing concepts for the general community, particularly to conscious consumers.

  15. Design and performance characteristics of a low-head recirculating aquaculture tank system for low salinity finfish production

    Water treatment components of a recirculating aquaculture system (RAS) consist mainly of: solid removal devices, biofiltration, aeration, degassing units, and water distribution. For each component, multiple options are available and the selection is based on system volume, system hydrodynamics, fis...

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

    Gu Li

    2012-10-01

    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.

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

    Gilles, Sylvain; Ismino, R.; Sanchez, H.; David, F; Nunez Rodriguez, Jesus (ed.); Dugué, Rémi; Darias, Maria Jose; Römer, U.

    2014-01-01

    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 zooplan...

  18. Water quality in recirculating aquaculture systems (ras) for arctic charr (salvelinus alpinus L.) culture.

    Isla Molleda , M.

    2008-01-01

    Recirculating aquaculture systems (RAS) for fish culture have been used for more than three decades. The interest in RAS is due to their have advantages such as greatly reduced land and water requirements in places where the water resources are limited; but the RAS have also disadvantages like the deterioration of the water quality if the water treatment processes within the system are not controlled properly. The water quality problems in RAS were associated with low DO and high fish waste m...

  19. Colonised Coasts : Aquaculture and Emergy Flows in the World System: Cases from Sri Lanka and the Philippines

    Bergquist, Daniel A.

    2008-01-01

    This thesis conceives aquaculture as a transfer of resources within and between different parts of the world system. It is argued that due to inappropriate human-nature interactions, resources tend to flow from the South to the North, as a process of coastal colonisation. To study this resource transfer, coastal aquaculture is ap-proached from a transdisciplinary perspective, integrating natural, social, economic and spatial aspects. By combining world system theory and general systems theory...

  20. Treatment of turtle aquaculture effluent by an improved multi-soil-layer system.

    Song, Ying; Huang, Yu-ting; Ji, Hong-fang; Nie, Xin-jun; Zhang, Zhi-yuan; Ge, Chuan; Luo, An-cheng; Chen, Xin

    2015-02-01

    Concentrated turtle aquaculture effluent poses an environmental threat to water bodies, and therefore needs to be treated prior to disposal. This study was conducted to assess the effect of multi-soil-layer (MSL) systems treating turtle aquaculture effluent with adding different amounts of sludge. Four MSL systems were constructed with dry weight ratios of sludge with 0%, 5%, 10%, and 20% (MSL 1, MSL 2, MSL 3, and MSL 4, respectively). The turtle aquaculture effluent had an average chemical oxygen demand (COD), ammonia nitrogen (NH4(+)-N) and total nitrogen (TN) concentration of 288.4, 213.4, and 252.0 mg/L, respectively. The COD/TN (C/N) ratio was 1.2. The results showed that the four MSL systems could effectively treat the COD, NH4(+)-N, and TN, and MSL 4 showed significantly improved NH4(+)-N removal efficiency, suggesting the potential of sludge addition to improve the turtle aquaculture effluent treatment. The average COD, TN, and NH4(+)-N removal ef?ciencies of MSL 4 were 70.3%, 66.5%, and 72.7%, respectively. To further interpret the contribution of microorganisms to the removal, the microbial community compositions and diversities of the four MSL systems were measured. Comparisons of the denaturing gradient gel electrophoresis (DGGE) profiles revealed that the amount of nitrifying bacteria and diversity in MSL 4 were higher than those in the other three systems. We concluded that adding 20% of sludge improved the NH4(+)-N removal and stability of the system for nitrification, due to the enrichment of the nitrifying bacteria in MSL 4. PMID:25644469

  1. Electronics and electronic systems

    Olsen, George H

    1987-01-01

    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

  2. A ZigBee Wireless Sensor Network for Monitoring an Aquaculture Recirculating System

    Francisco J. Espinosa-Faller

    2012-06-01

    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.

  3. Integration of aquaculture and agriculture: a route to sustainable farming systems

    Lightfoot, C.

    1990-01-01

    The integration of agriculture and aquaculture as a means of intensifying resource use and improving the productivity of many current farming practices in Southeast Asian and African countries is discussed. A brief account is given of work undertaken by ICLARM in Malawi and India regarding the improved use of marginal lands to integrate crops, vegetables, trees, livestock and fish, outlining also the various problems involved in the extension of such integrated fish farming systems.

  4. Use of Barley for the Purification of Aquaculture Wastewater in a Hydroponics System

    A. M. Snow; Abdel E Ghaly

    2008-01-01

    Barley was examined for its ability to remove nutrients from aquaculture wastewater. The effects of seed sterilization using ethanol and bleach and seed density on germination and plant growth were investigated. Surface sterilization of barley seeds had a negative impact on germination. Increasing the ethanol concentration and/or the bleach concentration reduced the germination percentage. Barley seeds were first germinated in water in the hydroponics system. The seedlings then received waste...

  5. Effect of Wind-solar Complementary Increasing Oxygen System in Aquaculture

    Guodong You; Shuying Lei; Jisheng Li; Yong Hou; Shangwen Cui

    2013-01-01

    In order to explore a sustainable aquaculture methodology, water was increased oxygen by a wind-solar power which was tested in a production period of the Penaeus vannamei in paper. The result shows that, compareing with the conventional aerating comparison, the system could improve water environment in ponds and dissolved oxygen, temperature, pH value and the content of nitrite stably and uniformly change; make full use of wind energy and solar energy clean energy, save 100% on power consump...

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

    Bovendeur, J.

    1989-01-01

    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 ...

  7. Systemic granuloma observed in Atlantic salmon Salmo salar raised to market size in a freshwater recirculation aquaculture system

    Systemic granuloma was observed in sampled adult Atlantic salmon Salmo salar raised to harvest size in a freshwater recirculation aquaculture system. The prevalence of this condition was estimated at 10-20% of the population, with affected individuals grossly demonstrating pathology in varying degre...

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

    Singh A.K.

    2009-06-01

    Full Text Available 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-resistant bacterialcounts were performed by spread plate method in culture media supplemented with the oxytetracycline.Sixty two resistant Gram negative isolates which represented the oxytetracycline-resistant bacterialpopulation, were randomly selected on nutrient agar supplemented with oxytetracycline (50μg/ml fromcarp farms and feed pellet samples. Among these bacterial isolates Flavobacterium (21%, Alcaligenes(14.5%, Aeromonas (11%, Pseudomonas (10% and Enterobacteriace (19% were the most frequent.The Escherichia, Serratia, Citrobacter, Enterobacter, Shigella and Proteus from Enterobacteriace wererecovered. Twelve isolates of oxytetracycline resistant bacteria were mainly dominated in adult fishes bythe genus Flavobacterium (23% and Enterobacteriace(41%. Selected strains exhibited high levels ofoxytetracycline resistance with minimum inhibitory concentrations (MICs ranging from 50 to600μg/ml.This study shows the presence of an important population of oxytetracycline-resistant bacteriain the microflora of Indian carp aquaculture farms. Therefore the environment of these farms might playimportant roles as reservoirs of bacteria carrying genetic determinants for high level tetracyclineresistance, prompting an important risk to public health.

  9. Bioflocs technology: an integrated system for the removal of nutrients and simultaneous production of feed in aquaculture

    Crab, Roselien

    2010-01-01

    Future development of intensive aquaculture must deal with its impacts on the environment in the form of water pollution and the use of fish oil and fish meal. The bioflocs technology simultaneously addresses both problems co-occurring with the further expansion of the industry. While maintaining good water quality within the aquaculture systems it produces additional feed for the cultured animals. In contrast to conventional water quality control techniques, the bioflocs technology offers a ...

  10. Analysis of river basin of Piarg aquaculture system

    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.

  11. TECHNOLOGY ASSESSMENT OF AQUACULTURE SYSTEMS FOR MUNICIPAL WASTEWATER TREATMENT

    The innovative and alternative technology provisions of the Clean Water Act of 1977 (PL 95-217) provide financial incentives to communities that use wastewater treatment alternatives to reduce costs or energy consumption over conventional systems. Some of these technologies have ...

  12. Daily micro particle distribution of an experimental recirculating aquaculture system – A case study

    Fernandes, Paulo; Pedersen, Lars-Flemming; Pedersen, Per Bovbjerg

    2014-01-01

    The particle size distribution (PSD) in a recirculating aquaculture system (RAS) was investigated duringa 24-h cycle. PSD was analyzed in water sampled at several locations in a recirculation loop containing a60-m drum filter, a submerged fixed-bed biofilter and a trickling filter.In relation to....... Permanent volumetric particle removal above 60 m (31% reductionin the relative contribution from each size by the drum filter) per passage, but marginal productionand removal of particles throughout the rest of the system further support the ˇ-value stability andconsequent PSD equilibrium.The results showed...

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

    Trent, J. D.

    2013-12-01

    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.

  14. Use of Barley for the Purification of Aquaculture Wastewater in a Hydroponics System

    A. M. Snow

    2008-01-01

    Full Text Available Barley was examined for its ability to remove nutrients from aquaculture wastewater. The effects of seed sterilization using ethanol and bleach and seed density on germination and plant growth were investigated. Surface sterilization of barley seeds had a negative impact on germination. Increasing the ethanol concentration and/or the bleach concentration reduced the germination percentage. Barley seeds were first germinated in water in the 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 or disease. The average crop height at harvest was 25.5 cm and the yield varied from 25 to 59 t haˉ1, depending on the seed density. The hydroponically grown barley was able to significantly reduce the pollution load of the aquaculture wastewater. The TS, COD, NH4+-N, NO2--N, NO3--N, and PO43--P reductions ranged from 52.7 to 60.5%, from 72.9 to 83.1%, from 76.0 to 76.0%, from 97.6 to 99.2%, from 76.9 to 81.6% and from 87.1 to 95.1%, respectively. However, the effluent produced from the hydroponics system had slightly higher levels of TS (420-485 mg Lˉ1 than the 480 mg Lˉ1 recommended for aquatic animals. A sedimentation/filtration unit should be added to the hydroponics system.

  15. Removal efficiency and balance of nitrogen in a recirculating aquaculture system integrated with constructed wetlands.

    Zhong, Fei; Liang, Wei; Yu, Tao; Cheng, Shui P; He, Feng; Wu, Zhen B

    2011-01-01

    The nitrogen (N) balance for aquaculture is an important aspect, especially in China, and it is attributed to the eutrophication in many freshwater bodies. In recent years, constructed wetlands (CWs) have been widely used in wastewater treatment and ecosystem restoration. A recirculating aquaculture system (RAS) consisting of CWs and 4 fish ponds was set up in Wuhan, China. Channel catfish (Ictalurus punctatus) fingerlings were fed for satiation daily for 168 days with 2 diets containing 5.49 % and 6.53 % nitrogen, respectively. The objectives of this study were to investigate the N budget in the RAS, and try to find out the feasibility of controlling N accumulation in the fish pond. It is expected that the study can provide a mass balance for the fate of N in the eco-friendly treatment system to avoid eutrophication. The results showed that the removal rates of ammonia (NH(+)(4)-N), sum of nitrate & nitrite (NO(-)(X)-N), and total nitrogen (TN) by the CWs were 20-55%, 38-84 % and 39-57 %, respectively. Denitrification in the CWs was the main pathway of nitrogen loss (41.67 %). Nitrogen accumulation in pond water and sediment accounted for 3.39 % and 12.65 % of total nitrogen loss, respectively. The nitrogen removal efficiency and budget showed that the CW could be used to control excessive nitrogen accumulation in fish ponds. From the viewpoint of the nitrogen pollution control, the RAS combined with the constructed wetland can be applied to ensure the sustainable development for aquaculture. PMID:21644158

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

    1982-01-01

    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.

  17. Predictive model of food intake of the Seabass Dicentrarchus labrax in closed aquaculture systems

    Allan T Souza

    2015-12-01

    Full Text Available Fish feeding is the main source of waste in aquaculture and is also responsible for most of the environmental impacts derived from this activity. The European Seabass Dicentrarchus labrax is one of the most farmed fishes in the continent, generating an important load of waste on the environment. The consumption of food in fishes is highly dependent on the water temperature and salinity, which create a source of variability on the amount of the ration consumed by fishes. This issue is often neglected by farmers, which aggravates the ration waste. The use of models in aquaculture is increasing in the recent years, and is an excellent tool to combine an increased production with the mitigation of environmental impacts. In this context, this study aimed at developing a predictive model of the D. labrax consumption rate in closed aquaculture systems. Based on the literature review we were able to develop a conceptual diagram and a prototype of the model using the STELLA software (isee®. The preliminary results indicated that the model was capable of predicting the ration consumption of the D. labrax according to the oscillations in the water temperature and salinity. The consumption rate and growth were higher at 21ºC and with a salinity of 28 psu. Laboratory assays are need to validate the models outputs, and they are scheduled to start in October 2015. Finally, the model’s structure, equations, inputs and outputs were integrated into an easy-to-use software developed by the FoodInTech® company, that will help farmers to increase their yields and reduce the waste of ration and the nutrient load on the environment.

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

    Serbulov A. V.

    2012-01-01

    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.

  19. Oxygen Consumption of Tilapia and Preliminary Mass Flows through a Prototype Closed Aquaculture System

    Muller, Matthew S.; Bauer, Clarence F.

    1994-01-01

    Performance of NASA's prototype CELSS Breadboard Project Closed Aquaculture System was evaluated by estimating gas exchange quantification and preliminary carbon and nitrogen balances. The total system oxygen consumption rate was 535 mg/hr kg/fish (cv = 30%) when stocked with Tilapia aurea populations (fresh weights of 97 +/- 19 to 147 +/- 36 g/fish for various trials). Oxygen consumption by T. aurea (260 mg/hr kg/fish) contributed to approximately one-half of total system demand. Continuous carbon dioxide quantification methods were analyzed using the,relation of carbon dioxide to oxygen consumption. Overall food conversion rates averaged 18.2 +/- 3.2%. Major pathways for nitrogen and carbon in the system were described with preliminary mass closure of 60-80% and 60% for nitrogen and carbon.

  20. Probiotic effects on cobia Rachycentron canadum larvae reared in a recirculating aquaculture system

    M. Angélica Garrido-Pereira

    2014-11-01

    Full Text Available 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 hatching. 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.

  1. A ZigBee Wireless Sensor Network for Monitoring an Aquaculture Recirculating System

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

    2012-12-01

    Full Text Available 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.

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

    Lin, Y.-F.; Jing, S.-R.; Lee, D.-Y

    2003-05-01

    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 (BOD{sub 5}, 24%), suspended solids (SS, 71%), chlorophyll a (chl-a, 88%), total ammonium (TAN, 57%), nitrite nitrogen (NO{sub 2}-N, 90%) and nitrate nitrogen (NO{sub 3}-N, 68%). Phosphate (PO{sub 4}-P) reduction was the least efficient (5.4%). The concentrations of SS, Chl-a, turbidity and NO{sub 3}-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 BOD{sub 5}, TAN and NO{sub 2}-N was found between the two systems. 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.

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

    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 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

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

    Suhr, Karin Isabel; Pedersen, Lars-Flemming; Nielsen, J.L.

    2014-01-01

    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.......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......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...

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

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

    2010-01-01

    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...

  6. Modelling for an improved integrated multi-trophic aquaculture system for the production of highly valued marine species

    Luana Granada

    2014-05-01

    Full Text Available Integrated multi-trophic aquaculture (IMTA is regarded as a suitable approach to limit aquaculture nutrients and organic matter outputs through biomitigation. Here, species from different trophic or nutritional levels are connected through water transfer. The co-cultured species are used as biofilters, and each level has its own independent commercial value, providing both economic and environmental sustainability. In order to better understand and optimize aquaculture production systems, dynamic modelling has been developed towards the use of models for analysis and simulation of aquacultures. Several models available determine the carrying capacity of farms and the environmental effects of bivalve and fish aquaculture. Also, in the last two decades, modelling strategies have been designed in order to predict the dispersion and deposition of organic fish farm waste, usually using the mean settling velocity of faeces and feed pellets. Cultured organisms growth, effects of light and temperature on algae growth, retention of suspended solids, biodegradation of nitrogen and wastewater treatment are examples of other modelled parameters in aquaculture. Most modelling equations have been developed for monocultures, despite the increasing importance of multi-species systems, such as polyculture and IMTA systems. The main reason for the development of multi-species models is to maximize the production and optimize species combinations in order to reduce the environmental impacts of aquaculture. Some multi-species system models are available, including from the polyculture of different species of bivalves with fish to more complex systems with four trophic levels. These can incorporate ecosystem models and use dynamic energy budgets for each trophic group. In the proposed IMTA system, the bioremediation potential of the marine seaweed Gracilaria vermiculophylla (nutrient removal performance and the Mediterranean filter-feeding polychaete Sabella spallanzanii (capacity to filter, accumulate and remove particles and bacterial groups co-cultured with the highly valued marine fish Diplodus sargus is assessed. This study includes to development of a model to mathematically describe the proposed IMTA system. The main focus of this model is optimize species combinations and yields from each trophic level. Such a mathematical description of the system also opens the possibility of developing simulators to study the purposed system, comparing it under different conditions.

  7. Comparative performance of CO2 measuring methods: marine aquaculture recirculation system application

    Pfeiffer, T.J.; Summerfelt, S.T.; Watten, B.J.

    2011-01-01

    Many methods are available for the measurement of dissolved carbon dioxide in an aqueous environment. Standard titration is the typical field method for measuring dissolved CO2 in aquaculture systems. However, titrimetric determination of dissolved CO2 in marine water aquaculture systems is unsuitable because of the high dissolved solids, silicates, and other dissolved minerals that interfere with the determination. Other methods used to measure dissolved carbon dioxide in an aquaculture water included use of a wetted CO2 probe analyzer, standard nomographic methods, and calculation by direct measurements of the water's pH, temperature, and alkalinity. The determination of dissolved CO2 in saltwater based on partial pressure measurements and non-dispersive infra-red (NDIR) techniques with a CO2 gas analyzer are widely employed for oceanic surveys of surface ocean CO2 flux and are similar to the techniques employed with the head space unit (HSU) in this study. Dissolved carbon dioxide (DC) determination with the HSU using a infra-red gas analyzer (IRGA) was compared with titrimetric, nomographic, calculated, and probe measurements of CO2 in freshwater and in saltwater with a salinity ranging from 5.0 to 30 ppt, and a CO2 range from 8 to 50 mg/L. Differences in CO2 measurements between duplicate HSUs (0.1–0.2 mg/L) were not statistically significant different. The coefficient of variation for the HSU readings averaged 1.85% which was better than the CO2 probe (4.09%) and that for the titrimetric method (5.84%). In all low, medium and high salinity level trials HSU precision was good, averaging 3.39%. Differences existed between comparison testing of the CO2 probe and HSU measurements with the CO2 probe readings, on average, providing DC estimates that were higher than HSU estimates. Differences between HSU and titration based estimates of DC increased with salinity and reached a maximum at 32.2 ppt. These differences were statistically significant (P < 0.05) at all salinity levels greater than 0.3 ppt. Results indicated reliable replicated results from the head space unit with varying salinity and dissolved carbon dioxide concentrations.

  8. Characterization of integrons and tetracycline resistance determinants in Aeromonas spp. isolated from South African aquaculture systems.

    Jacobs, Liezl; Chenia, Hafizah Y

    2007-03-20

    An increasing incidence of multidrug resistance amongst Aeromonas spp. isolates, which are both fish pathogens and emerging opportunistic human pathogens, has been observed worldwide. This can be attributed to the horizontal transfer of mobile genetic elements, viz.: plasmids and class 1 integrons. The antimicrobial susceptibilities of 37 Aeromonas spp. isolates, from tilapia, trout and koi aquaculture systems, were determined by disc-diffusion testing. The plasmid content of each isolate was examined using the alkaline lysis protocol. Tet determinant type was determined by amplification using two degenerate primer sets and subsequent HaeIII restriction. The presence of integrons was determined by PCR amplification of three integrase genes, as well as gene cassettes, and the qacEDelta1-sulI region. Thirty-seven Aeromonas spp. isolates were differentiated into six species by aroA PCR-RFLP, i.e., A. veronii biovar sobria, A. hydrophila, A. encheleia, A. ichtiosoma, A. salmonicida, and A. media. High levels of resistance to tetracycline (78.3%), amoxicillin (89.2%), and augmentin (86.5%) were observed. Decreased susceptibility to erythromycin was observed for 67.6% of isolates. Although 45.9% of isolates displayed nalidixic acid resistance, majority of isolates were susceptible to the fluoroquinolones. The MAR index ranged from 0.12 to 0.59, with majority of isolates indicating high-risk contamination originating from humans or animals where antibiotics are often used. Plasmids were detected in 21 isolates, with 14 of the isolates displaying multiple plasmid profiles. Single and multiple class A family Tet determinants were observed in 27% and 48.7% of isolates, respectively, with Tet A being the most prevalent Tet determinant type. Class 1 integron and related structures were amplified and carried different combinations of the antibiotic resistance gene cassettes ant(3'')Ia, aac(6')Ia, dhfr1, oxa2a and/or pse1. Class 2 integrons were also amplified, but the associated resistance cassettes could not be identified. Integrons and Tet determinants were carried by 68.4% of isolates bearing plasmids, although it was not a strict association. These plasmids could potentially mobilize the integrons and Tet determinants, thus transferring antimicrobial resistance to other water-borne bacteria or possible human pathogens. The identification of a diversity of resistance genes in the absence of antibiotic selective pressure in Aeromonas spp. from aquaculture systems highlights the risk of these bacteria serving as a reservoir of resistance genes, which may be transferred to other bacteria in the aquaculture environment. PMID:17173998

  9. Tracing dissolved organic matter (DOM) from land-based aquaculture systems in North Patagonian streams

    Nimptsch, Jorge; Woelfl, Stefan; Osorio, Sebastian; Ebersbach, Paul; von Tümpling, Wolf; Palma, Rodrigo; Encina, Francisco; Figueroa, David; Kamjunke, Norbert; Graeber, Daniel

    2015-01-01

    Chile is the second largest producer of salmonids worldwide. The first step in the production of salmonids takes place in land-based aquacultures. However, the effects of the discharge from these aquacultures on stream dissolved organic matter (DOM) content, molecular composition and degradabilit...

  10. Abnormal swimming behavior and increased deformities in rainbow trout Oncorhynchus mykiss cultured in low exchange water recirculation aquaculture systems

    Two studies were conducted to determine if accumulating water quality parameters would negatively impact rainbow trout Oncorhynchus mykiss health and welfare within water recirculation aquaculture systems (WRAS) that were operated at low and near-zero water exchange, with and without ozonation, and ...

  11. Electron beam irradiation, oxygen, and temperature effects on nucleotide degradation in stored aquaculture hybrid striped bass fillets

    Skinless fillets from commercially-grown aquaculture hybrid striped bass (Morone saxatilis x M. chrysops) were electron beam-irradiated in the presence of air or vacuum-packaged and stored at 4C and -20C for 14 days. A mean low dose level of 2.0 or 3.0 kGy (+/- 0.5 kGy) and high dose level of 20 kGy (+/- 4 kGy) were used for irradiated samples. Hypoxanthine (Hx) concentrations, Ki-values ([(INO + Hx)/(IMP + INO + Hx)] x 100), and H-values ([(Hx)/(IMP + INO + Hx)] x 100) indicated that irradiation did not influence the rate of nucleotide degradation compared with nonirradiated controls at either refrigerated or frozen temperatures. Vacuum packaging or freezing of stored samples resulted in lower H-values and Hx contents compared with nonirradiated controls regardless of irradiation treatment

  12. Effects of feed loading on nitrogen balances and fish performance in replicated recirculating aquaculture systems

    Pedersen, Lars-Flemming; Suhr, Karin Isabel; Dalsgaard, Anne Johanne Tang; Pedersen, Per Bovbjerg; Arvin, Erik

    /L at steady state, and the concentration of nitrogenous compounds and organic matter were all positively correlated to feed loading.The TAN loading to the RAS from the specific feed type was assessed in a separate mass-balance study and used as input in a descriptive mathematical model (AQUASIM......This study investigated the effects of applying four fixed feed loadings to three replicated recirculating aquaculture systems (RAS) on water quality changes, nitrogenous balances and growth performance of rainbow trout (Oncorhynchus mykiss).Feed loadings ranged from 1.6 to 6.3kgfeed/m3 make......® software) developed to simulate processes affecting N mass-balances in the RAS. Nitrification kinetic rate constants were applied to the biofilter, and fractions of nitrifiers in suspended solids in the water phase were estimated based on existing information from waste water treatment processes. Two model...

  13. BIOFILTERS IN AQUACULTURE

    Ivo Šarić

    2010-07-01

    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.

  14. Strategies to enhance the competitiveness of semi-intensive aquaculture systems in costal earth ponds: the organic aquaculture approach

    Manuel Sardinha; Sofia Engrola; Paulo Gray

    2014-01-01

    Earthen ponds are the main production system for European seabass (Dicentrarchus labrax) and gilthead seabream (Sparus aurata) in Portugal and in Southern Spain. Production costs in this low productivity farming system are higher compared to intensive cage farms, and its economic sustainability depends on product differentiation and optimization of production. The development of new farming protocols, to enhance productivity of ponds and lagoons, or the implementation of certification process...

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

    Pedersen, Lars-Flemming

    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......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...... ≥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...

  16. The role of a fish pond in optimizing nutrient flows in integrated agriculture-aquaculture farming systems

    Nhan, D.K.

    2007-01-01

      In the Mekong delta, the Vietnamese government promoted integrated agriculture-aquaculture (IAA) farming systems as an example of sustainable agriculture. An important advantage of IAA-farming is the nutrient linkage between the pond and terrestrial components within a farm, which allows to improve resource use efficiency and income while reducing environmental impacts. This study monitored and analyzed water use in and nutrient flows through ponds that are part of an IAA-farming system. Th...

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

    Edward H Allison

    2007-12-01

    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.

  18. Aquaculture Information Package

    Boyd, T.; Rafferty, K. [editors

    1998-01-01

    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.

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

    Eriksson, Hampus

    2012-01-01

    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...

  20. Broodstock management of the fine flounder Paralichthys adspersus (Steindachner, 1867 using recirculating aquaculture systems

    Lili Carrera

    2013-03-01

    Full Text Available 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.

  1. Impact of water quality on the bacterial populations and off-flavours in recirculating aquaculture systems.

    Auffret, Marc; Yergeau, Étienne; Pilote, Alexandre; Proulx, Émilie; Proulx, Daniel; Greer, Charles W; Vandenberg, Grant; Villemur, Richard

    2013-05-01

    A variety of factors affecting water quality in recirculating aquaculture systems (RAS) are associated with the occurrence of off-flavours. In this study, we report the impact of water quality on the bacterial diversity and the occurrence of the geosmin-synthesis gene (geoA) in two RAS units operated for 252 days. Unit 2 displayed a higher level of turbidity and phosphate, which affected the fresh water quality compared with unit 1. In the biofilter, nitrification is one of the major processes by which high water quality is maintained. The bacterial population observed in the unit 1 biofilter was more stable throughout the experiment, with a higher level of nitrifying bacteria compared with the unit 2 biofilter. Geosmin appeared in fish flesh after 84 days in unit 2, whereas it appeared in unit 1 after 168 days, but at a much lower level. The geoA gene was detected in both units, 28 days prior to the detection of geosmin in fish flesh. In addition, we detected sequences associated with Sorangium and Nannocystis (Myxococcales): members of these genera are known to produce geosmin. These sequences were observed at an earlier time in unit 2 and at a higher level than in unit 1. This study confirms the advantages of new molecular methods to understand the occurrence of geosmin production in RAS. PMID:23228051

  2. Performance evaluation of the compact aquaculture system integrating submerged fibrousnitrifying biofilters

    Sorawit Powtongsook

    2012-02-01

    Full Text Available This experiment assessed the performance of submerged fibrous nitrifying biofilters (SFNBs to carry out the zerowaterexchange tilapia cultivation. Without biofilter cleaning, the SFNBs (21 m of biofilter length were susceptible tohydrogen sulfide production when operating beyond the aquaculture density of 13.62 kg/m3. The SFNBs were able tomaintain total ammonia nitrogen (TAN and nitrite below 1.0 mg N/L throughout the experiment and could handle inorganicnitrogen loading as high as 38.6 mg N/L/day when the solid removal from biofilters was performed biweekly. Ammoniumdegradation rate measured at the end of this study was 380±66 mg N/m2/day for biofilters subjected to cleaning. A significantlylower rate of 41.4±2.86 mg N/m2/day was associated with biofilters without any solid removal. Finally, the SFNBsshould be attractive for budget-limited farmers since they are simple to build and operate and can provide alternatives tocage-cultured systems.

  3. Membrane filtration coupled with chemical precipitation to treat recirculating aquaculture system effluents.

    Yang, Ling; Zhou, Hongde; Moccia, Richard

    2006-01-01

    Effluents from recirculating aquaculture systems (RAS) contain high concentrations of nitrogen and phosphorous wastes and thus often require proper treatment to prevent potential detrimental impacts on receiving water bodies. The purpose of this study was to evaluate the feasibility of membrane filtration coupled with chemical precipitation as a pretreatment step with emphasis on phosphorus removal from RAS effluents. Chemical precipitation tests were conducted by adding magnesium chloride and alum at different chemical concentrations and pH values, respectively. Crossflow, flat-sheet membrane filtration modules were used to examine the effects of transmembrane pressure and crossflow velocity in terms of solid/liquid separation efficiency and permeate flux decline. The results showed that membrane filtration can effectively separate the phosphorus precipitates after chemical precipitation. The total phosphorus in the treated effluent was reduced to less than 0.05 mg L(-1) with a removal efficiency of more than 90%. However, much lower removal efficiencies were obtained for total organic carbon (TOC), total nitrogen, and turbidity. It was concluded that membrane filtration coupled with chemical precipitation can become an effective, compact treatment technology to meet the stringent regulatory requirements for RAS effluent discharge. PMID:17071913

  4. Conditioning of broodstock of tiger grouper, Epinephelus fuscoguttatus, in a recirculating aquaculture system

    Saleem Mustafa

    2015-11-01

    Full Text Available Closing the cycle of commercial species of fish in a recirculating aquaculture system is gaining importance for a number of practical advantages. Founder broodstock originating from the wild population is conditioned to live in hatchery tanks under suitable environmental and feeding conditions and is induced to breed. The juveniles are grown to maturity and facilitated to spawn in captivity to close the life cycle in the hatchery. This experiment was carried out on tiger grouper (Epinephelus fuscoguttatus. After preliminary observations, it was possible to identify appropriate environmental conditions in terms of water quality parameters, volume of broodstock tanks and ration. Growth was nearly isometric (growth exponent = 2.9185 and the condition factor = 1.86. This reflected good management conditions. Cues that trigger sex reversal in this protogynous fish in the hatchery were different from those that operate in nature. It appears that the differentiation of some individuals of a cohort into male sex is linked to socio-demographic cues as well as internal condition of the fish because it related to age and physiological condition. This view was reinforced by a lack of response in young fish to similar cues. The information generated through this study defines what is required for optimum conditioning of tiger grouper broodstock and explains the cues involved in sex differentiation.

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

    Larsen, Bodil Katrine; Dalsgaard, Anne Johanne Tang; Pedersen, Per Bovbjerg

    2015-01-01

    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. Observations on side-swimming rainbow trout in water recirculation aquaculture systems.

    Good, Christopher; Davidson, John; Kinman, Christin; Kenney, P Brett; Bæverfjord, Grete; Summerfelt, Steven

    2014-12-01

    During a controlled 6-month study using six replicated water recirculation aquaculture systems (WRASs), it was observed that Rainbow Trout Oncorhynchus mykiss in all WRASs exhibited a higher-than-normal prevalence of side swimming (i.e., controlled, forward swimming but with misaligned orientation such that the fish's sagittal axis is approximately parallel to the horizontal plane). To further our understanding of this abnormality, a substudy was conducted wherein side swimmers and normally swimming fish were selectively sampled from each WRAS and growth performance (length, weight), processing attributes (fillet yield, visceral index, ventrum [i.e., thickness of the ventral "belly flap"] index), blood gas and chemistry parameters, and swim bladder morphology and positioning were compared. Side swimmers were found to be significantly smaller in length and weight and had less fillet yield but higher ventrum indices. Whole-blood analyses demonstrated that, among other things, side swimmers had significantly lower whole-blood pH and higher Pco2. Side swimmers typically exhibited swim bladder malformations, although the positive predictive value of this subjective assessment was only 73%. Overall, this study found several anatomical and physiological differences between side-swimming and normally swimming Rainbow Trout. Given the reduced weight and fillet yield of market-age side swimmers, producers would benefit from additional research to reduce side-swimming prevalence in their fish stocks. PMID:25250476

  7. Environmental sustainability assessment of a microalgae raceway pond treating aquaculture wastewater: From up-scaling to system integration.

    Sfez, Sophie; Van Den Hende, Sofie; Taelman, Sue Ellen; De Meester, Steven; Dewulf, Jo

    2015-08-01

    The environmental sustainability of aquaculture wastewater treatment by microalgal bacterial flocs (MaB-flocs) in an outdoor raceway pond was analyzed using life cycle assessment. Pikeperch aquaculture wastewater treated at pilot scale (Belgium; 28m(2)) and industrial scale (hypothetical up-scaling; 41 ponds of 245m(2)) were compared. The integration of the MaB-floc raceway pond in a broader aquaculture waste treatment system was studied, comparing the valorisation of MaB-flocs as shrimp feed and as biogas. Up-scaling improves the resource footprint of the plant (848MJex,CEENEkg(-1) MaB-floc TSS at pilot scale and 277MJex,CEENEkg(-1) MaB-floc TSS at industrial scale) as well as its carbon footprint and eutrophication potential. At industrial scale, the valorisation of MaB-flocs as shrimp feed is overall more sustainable than as biogas but improvements should be made to reduce the energy use of the MaB-floc raceway pond, especially by improving the energy-efficiency of the pond stirring system. PMID:25965258

  8. Errors in experimental design and statistical analysis of aquaculture diet evaluation studies induced by filtration systems

    Michael F. Tlusty

    2010-07-01

    Full Text Available While single factor diet studies appear to be of simple design, the space constraints in aquaculture caused by the need to filter the aqueous media often c reate constraints on the implementation of the experimental design. A number of papers have been published in which the experimental design and subsequent analysis is incorrect. This paper reviews the principles of experimental design as it related to single factor diet evaluation studies in aquaculture. By adhering tosimple design principles to ensure that experimental units are independent, the data generated by future experiments will be of high quality and results more robust.

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

    Yuyi Tang

    2014-08-01

    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.

  10. Inland marine fish culture in low-salinity recirculating aquaculture systems

    Expansion of marine aquaculture is challenged by the high cost and limited availability of coastal land and water resources, effluent concerns, high production costs, restricted growing seasons, lack of quality seedstock, and inadequate regulatory and permitting processes. Many of these constraints...

  11. Overview of sustainable marine aquaculture systems engineering projects with emphasis on biofiltration

    The rate of ammonia removal for moving bed and static bed biofilters with plastic media was determined for various feed loading rates, flow rates, and salinity. Ammonia removal rates in the eight propeller-wash floating plastic bead filters (0.71 m3) utilized in the 45 m3 recirculating aquaculture ...

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

    Jepsen, Per Meyer; Højgaard, Jacob Kring; Drillet, Guillaume; Mahjoub, Mohamed-Sofiane; Rais, Mouloud; Novac, Aliona; Schjelde, Johannes; Andersen, Claus V. B.; Hansen, Benni Winding

    2014-01-01

    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...

  13. Optimizing Hydraulic Retention Times in Denitrifying Woodchip Bioreactors Treating Recirculating Aquaculture System Wastewater.

    Lepine, Christine; Christianson, Laura; Sharrer, Kata; Summerfelt, Steven

    2016-05-01

    The performance of wood-based denitrifying bioreactors to treat high-nitrate wastewaters from aquaculture systems has not previously been demonstrated. Four pilot-scale woodchip bioreactors (approximately 1:10 scale) were constructed and operated for 268 d to determine the optimal range of design hydraulic retention times (HRTs) for nitrate removal. The bioreactors were operated under HRTs ranging from 6.6 to 55 h with influent nitrate concentrations generally between 20 and 80 mg NO-N L. These combinations resulted in N removal rates >39 g N m d, which is greater than previously reported. These high removal rates were due in large part to the relatively high chemical oxygen demand and warm temperature (∼19°C) of the wastewater. An optimized design HRT may not be the same based on metrics of N removal rate versus N removal efficiency; longer HRTs demonstrated higher removal efficiencies, and shorter HRTs had higher removal rates. When nitrate influent concentrations were approximately 75 mg NO-N L ( = 6 sample events), the shortest HRT (12 h) had the lowest removal efficiency (45%) but a significantly greater removal rate than the two longest HRTs (42 and 55 h), which were N limited. Sulfate reduction was also observed under highly reduced conditions and was exacerbated under prolonged N-limited environments. Balancing the removal rate and removal efficiency for this water chemistry with a design HRT of approximately 24 h would result in a 65% removal efficiency and removal rates of at least 18 g N m d. PMID:27136146

  14. Assessing the sustainability of brackish water aquaculture systems in the Philippines. Working Paper 4: Aquaculture and poverty - a case study of five coastal communities in the Philippines

    Irz, X.T.; Stevenson, J R; Tanoy, A.; Villarante, P.; Morissens, P.

    2003-01-01

    After reviewing the rather thin literature on the subject, we investigate the relationship between aquaculture and poverty based on a case study of five coastal communities in the Philippines. The analysis relies on a data set collated through a questionnaire survey of 148 households randomly selected in these five communities. The methodological approach combines the qualitative analysis of how this relationship is perceived by the surveyed households and a quantitative analysis of the le...

  15. Aquaculture information package

    Boyd, T.; Rafferty, K.

    1998-08-01

    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.

  16. Trophic structure in a pilot system for the integrated multi-trophic aquaculture off the east coast of Korean peninsula as determined by stable isotopes

    Highlights: • A pilot system for the integrated multi-trophic aquaculture was installed. • The black rockfish, sea cucumber, oyster, and macroalgae were co-cultured. • Co-cultured sea cucumber at the IMTA site assimilated aquaculture wastes. • Fish cage-waste contribution to food web in/around the IMTA system was minor. • The sea cucumber was identified as an extractive species of fish cage wastes. - Abstract: To assess the potential for nutritional exploitation of caged-fish-derived waste through the use of extractive co-cultured species in a pilot system for an integrated multi-trophic aquaculture (IMTA), we compared their C and N stable isotope ratios with those of uncultured macroinvertebrates in and around the system. Black rockfish were co-cultured with sea cucumber, oyster, and two macroalgae as extractive species. Isotope signatures of the co-cultured sea cucumber at the IMTA site differed from those at the control site, indicating their assimilation of aquaculture wastes. In contrast, δ13C and δ15N of individual taxa of the cultured oyster and uncultured invertebrates were consistent between sites, suggesting a minor contribution of the aquaculture waste to benthic and pelagic food chains in and around the IMTA system. These results provide evidence of the suitability of using sea cucumber as an extractive species to reduce the impact of a monoculture system on the ambient environment

  17. ECONOMIC ANALYSIS OF FRESHWATER AQUACULTURE PRODUCTION: A COMPARATIVE ANALYSIS OF DIFFERENT PRODUCTION SYSTEMS

    H. Kumar

    2013-01-01

    Full Text Available India produced 8.29 million tonnes of fish in 2010-2011. The industry contributes nearly INR 200 trillion to the national economy, forming 1.4 percent of national gross domestic product (GDP and 5.4 percent of Agricultural GDP. At present, almost 84 percent of the total inland fish production, in the country is contributed by freshwater aquaculture amounting to 3.9 million tonnes in 2008-09. Further, the potential of the vast freshwater resources covering 6.7 million hectare is yet to be fully realized. The freshwater aquaculture which began as small scale activity of stocking ponds with fish seed collected from riverine sources during early fifties in rural Bengal has now transformed into a major economic activity in almost all states. There is a further need to make the sector more vibrant so as to achieve the predicted target of 15 kg per capita fish availability in the country by 2030.

  18. Comparison of Atlantic salmon net pen and recirculating aquaculture systems:economical, technological and environmental issues

    Dekhtyarev, Vitaly

    2014-01-01

    The modern aquaculture industry is a rapidly developing sector of the fisheries industry. Among the fish species reared in marine waters Atlantic salmon (Salmo salar) shares a significant part. Nowadays, the largest salmon producing countries are Norway, Chile and Scotland. The common technology used in the salmon production is a sea cage, which is presented in a form of floating plastic rings or robust metal installations fastened to a barge. In both cases, the fish is placed ...

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

    R Fadhil

    2011-01-01

    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...

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

    Suhr, Karin Isabel; Letelier Gordo, Carlos Octavio; Prat Busquets, Pau

    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...

  1. Single-sludge denitrification in recirculating aquaculture systems: effects of pre-fermentation and pH

    Suhr, Karin Isabel; Letelier-Gordo, Carlos Octavio; Prat Busquets, Pau

    2015-01-01

    Single-sludge denitrification (DN) reactors in aquaculture use the carbonous solid fish waste produced in the system to reduce the discharged nitrate load. The solid waste is available for denitrifiers when present in soluble, readily biodegradable form, and the transformation is accomplished by...... bacterial hydrolysis and fermentation. The objective of this study was to quantify the effect of pre-fermentation of solid fish waste on single-sludge DN reactor efficiency. Pre-fermentation times tested were 0 d (no pre-fermentation), 1 d, 5 d, and 10 d, and the efficiency was quantified as the potential...

  2. Phosphatase activity and specific methanogenic activity in an anaerobic reactor treating sludge from a brackish recirculation aquaculture system.

    Zhang, Xuedong; Ferreira, Rui B; Spanjers, Henri; van Lier, Jules B

    2013-01-01

    Anaerobic treatment of high salinity sludge from marine/brackish recirculation aquaculture systems is potentially limited by inhibition of enzymatic activities and cell lysis resulting from high osmotic pressures. To further address these limitations the following investigations were conducted: effect of salinity on phosphatase activity (PA), soluble microbial products (SMP) production, and presence of extracellular polymeric substances (EPS); effect of iron (III) chloride (FeCl3) on PA and specific methanogenic activity (SMA); effect of addition of the compatible solute glycine betaine (GB) and potassium on PA, as well as on SMP and EPS production, all under saline conditions. The results show that salinity has different effects on PA of anaerobes under starvation and feeding conditions. FeCl3 increased the SMA of the sludge by 22.5% at 100 mg FeCl3/L compared with a control group (0 mg FeCl3/L). Furthermore, results of analysis of variance tests show that betaine increased the polysaccharide content of EPS and polypeptide content of SMP. However, addition of 1 mM potassium chloride did not show a significant effect on EPS and SMP composition. In conclusion, anaerobic digestion of salty sludges from a brackish aquaculture recirculation system may not be negatively affected by FeCl3 addition to concentrate waste streams, whereas GB boosts the production of SMP and EPS. PMID:23863432

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

    R Fadhil

    2011-01-01

    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.

  4. Animal protein production modules in biological life support systems: Novel combined aquaculture techniques based on the closed equilibrated biological aquatic system (C.E.B.A.S.)

    Blüm, V.; Andriske, M.; Kreuzberg, K.; Schreibman, M. P.

    Based on the experiences made with the Closed Equilibrated Biological Aquatic System (C.E.B.A.S.) which was primarily deveoloped for long-term and multi-generation experiments with aquatic animals and plants in a space station highly effective fresh water recycling modules were elaborated utilizing a combination of ammonia oxidizing bacteria filters and higher plants. These exhibit a high effectivity to eliminate phosphate and anorganic nitrogen compounds and arc. in addidition. able to contribute to the oxygen supply of the aquatic animals. The C.E.B.A.S. filter system is able to keep a closed artificial aquatic ecosystem containing teleost fishes and water snails biologically stable for several month and to eliminate waste products deriving from degraded dead fishes without a decrease of the oxygen concentration down to less than 3.5 mg/l at 25 °C. More advanced C.E.B.A.S. filter systems, the BIOCURE filters, were also developed for utilization in semiintensive and intensive aquaculture systems for fishes. In fact such combined animal-plant aquaculture systems represent highly effective productions sites for human food if proper plant and fish species are selected The present papers elucidates ways to novel aquaculture systems in which herbivorous fishes are raised by feeding them with plant biomass produced in the BIOCURE filters and presents the scheme of a modification which utilizes a plant species suitable also for human nutrition. Special attention is paid to the benefits of closed aquaculture system modules which may be integrated into bioregenerative life support systems of a higher complexity for, e. g.. lunar or planetary bases including some psychologiccal aspects of the introduction of animal protein production into plant-based life support systems. Moreover, the basic reproductive biological problems of aquatic animal breeding under reduced gravity are explained leading to a disposition of essential research programs in this context.

  5. 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

    Serbulov Alexey

    2012-01-01

    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.

  6. Enhancement of Anaerobic Digestion to Treat Saline Sludge from Recirculating Aquaculture Systems

    Luo, Guo-zhi; Ma, Niannian; Li, Ping; Tan, Hong-xin; Liu, Wenchang

    2015-01-01

    The effectiveness of carbohydrate addition and the use of ultrasonication as a pretreatment for the mesophilic anaerobic digestion of saline aquacultural sludge was assessed. Analyses were conducted using an anaerobic sequencing batch reactor (ASBR), which included stopped gas production attributed to the saline inhibition. After increasing the C?:?N ratio, gas production was observed, and the total chemical oxygen demand (TCOD) removal efficiency increased from 75% to 80%. The TCOD removal efficiency of the sonication period was approximately 85%, compared to 75% for the untreated waste. Ultrasonication of aquaculture sludge was also found to enhance the gas production rate and the TCOD removal efficiency. The average volatile fatty acid (VFA) to alkalinity ratios ranged from 0.1 to 0.05, confirming the stability of the digesters. Furthermore, soluble chemical oxygen demand (SCOD), VFA, and PO43? concentrations increased in the effluents. There was a 114% greater gas generation during the ultrasonication period, with an average production of 0.08?g COD/L·day?1. PMID:26301258

  7. Prototype recirculating aquaculture system design for juvenile red drum production as part of the Florida Fish and Wildlife Conservation commission’s Hatchery Network Initative

    A prototype recirculating aquaculture system for the production of red drum (Sciaenops ocellatus) includes four 10-foot diameter by four foot height tanks for a tank volume of approximately 300 ft3 each (2200 gallons). Water flow for the system is provided for by a low head propeller pump which prov...

  8. Electron beam focusing system

    Dikansky, N.; Nagaitsev, S.; Parkhomchuk, V.

    1997-09-01

    The high energy electron cooling requires a very cold electron beam. Thus, the electron beam focusing system is very important for the performance of electron cooling. A system with and without longitudinal magnetic field is presented for discussion. Interaction of electron beam with the vacuum chamber as well as with the background ions and stored antiprotons can cause the coherent electron beam instabilities. Focusing system requirements needed to suppress these instabilities are presented.

  9. An Overview of Aquaculture in the Nordic Countries

    Paisley, Larry; Ariel, Ellen; Lyngstad, T. M.; Jónsson, G.; Vennerström, P.; Hellström, A.; Østergaard, P.

    2010-01-01

    , 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 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....... 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...

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

    Trang, Ngo Thuy Diem; Schierup, Hans-Henrik; Brix, Hans

    2010-01-01

    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...

  11. Temperature effects on biomass, geosmin, and 2-methylisoborneol production and cellular activity by Nocardia spp. and Streptomyces spp. isolated from rainbow trout recirculating aquaculture systems

    Isolates of Nocardia cummidelens, Nocardia fluminea, Streptomyces albidoflavus, and Streptomyces luridiscabiei attributing to geosmin-related off-flavor in rainbow trout (Oncorhynchus mykiss) raised in recirculating aquaculture systems (RAS) were evaluated for the effect of temperature (10-30 degree...

  12. Public, animal, and environmental health implications of aquaculture.

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

    1997-01-01

    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...

  13. Establishment of a real-time PCR method for quantification of geosmin-producing Streptomyces spp. in recirculating aquaculture systems.

    Auffret, Marc; Pilote, Alexandre; Proulx, Emilie; Proulx, Daniel; Vandenberg, Grant; Villemur, Richard

    2011-12-15

    Geosmin and 2-methylisoborneol (MIB) have been associated with off-flavour problems in fish and seafood products, generating a strong negative impact for aquaculture industries. Although most of the producers of geosmin and MIB have been identified as Streptomyces species or cyanobacteria, Streptomyces spp. are thought to be responsible for the synthesis of these compounds in indoor recirculating aquaculture systems (RAS). The detection of genes involved in the synthesis of geosmin and MIB can be a relevant indicator of the beginning of off-flavour events in RAS. Here, we report a real-time polymerase chain reaction (qPCR) protocol targeting geoA sequences that encode a germacradienol synthase involved in geosmin synthesis. New geoA-related sequences were retrieved from eleven geosmin-producing Actinomycete strains, among them two Streptomyces strains isolated from two RAS. Combined with geoA-related sequences available in gene databases, we designed primers and standards suitable for qPCR assays targeting mainly Streptomyces geoA. Using our qPCR protocol, we succeeded in measuring the level of geoA copies in sand filter and biofilters in two RAS. This study is the first to apply qPCR assays to detect and quantify the geosmin synthesis gene (geoA) in RAS. Quantification of geoA in RAS could permit the monitoring of the level of geosmin producers prior to the occurrence of geosmin production. This information will be most valuable for fish producers to manage further development of off-flavour events. PMID:22060964

  14. Aquaculture and food crisis: opportunities and constraints.

    Liao, I Chiu; Chao, Nai-Hsien

    2009-01-01

    Fish farming, now well known as aquaculture, has been well recognized since the ancient era. The first written document on fish culture was published in China in 475 BC, and the first koi pond was constructed at the Japanese Imperial Palace grounds during 71-130 AD. In recent years, aquaculture has progressively played an important role in the provision of: animal protein and gourmet cuisines, job opportunities, and foreign currency for developing countries. Asian countries produce around 91 percent of the world's total aquaculture production. Among the top ten aquaculture-producing countries, nine are from Asia. The current global population consist of more than 6.5 billion individuals; over one billion of which face hunger problem. In the highly populated Asia-Pacific region with moderately high-productivity, 642 million people are still facing hunger. Being a proficient and potential source of animal protein, aquaculture will play an increasing and important role in solving the world food problem in the future. This paper discusses both the opportunities and constraints in the aquaculture industry, specifically in the Asia-Pacific region, and its possible role in solving the current global food crisis. Strategies including promotion and adoption of traceability and HACCP systems for food safety, and marketing management for aquaculture products are also suggested. It is hoped that traditional administration of aquaculture management for survival, profit, as well as food safety will successfully match sustainability management to meet the urgent global need for food. PMID:19965349

  15. Aquaculture-fisheries interactions

    Mikkelsen, Eirik

    2006-01-01

    Assuming externalities from aquaculture to fisheries, we use a Verhulst-Schaefer model of fish population-dynamics and production, coupled with an aquaculture production model, to investigate effects on open-access and rent-maximising fisheries. Externalities are modelled by letting carrying capacity, intrinsic growth rate or catchability coefficient in the fishery depend on aquaculture production. We find that the different externalities can give opposite effects on steady state fishing effo...

  16. Marketing Netcoatings for Aquaculture

    Martin, Robert J.

    2014-01-01

    Unsustainable harvesting of natural fish stocks is driving an ever growing marine aquaculture industry. Part of the aquaculture support industry is net suppliers who provide producers with nets used in confining fish while they are grown to market size. Biofouling must be addressed in marine environments to ensure maximum product growth by maintaining water flow and waste removal through the nets. Biofouling is managed with copper and organic biocide based net coatings. The aquaculture indust...

  17. Cultivable intestinal microbiota of yellowtail juveniles (Seriola lalandi in an aquaculture system

    Eduardo Aguilera

    2013-07-01

    Full Text Available 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 Seriola 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.

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

    G. STEFAN

    2013-12-01

    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.

  19. Isotopes in aquaculture research

    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

  20. Aquaculture in mangrove environment

    Parulekar, A.H.

    A general account of aquaculture of India in mangrove environment has been discussed. In-spite of being a none-too-tidal aquaculture site, the estuaries and backwaters fringEd. by mangrove vegetation have long been used for rearing and fattening...

  1. Aquaculture activities in Fiji

    Vereivalu, T

    1989-01-01

    Fiji has no aquaculture tradition, but the Government is engaged in aquaculture production since 1969, with the help of other countries and international organization like F.A.O. Some species have been tested: Fishes: Grass carp (Ctenopharyngodon idellus ) and Tilapia ; Molluscs: Oyster (Crassostrea echinata ) and Mussel (Mytilus viridis ); Crustacean: freshwater prawn (Macrobrachium rosenbergii ) and shrimps (Penaeus monodon, P. indicus, P. stylirostris ).

  2. Aquaculture in New Zealand

    Hayden, B.

    1989-01-01

    Aquaculture is a relatively new activity in New Zealand. The indigenous rock oyster (Saccostrea glomerata ) was the first target for aquaculture in the 1930's although it was not intensively cultured until the 1960's. The faster growing Pacific oyster (Crassostrea gigas ) appeared in 1969/70 and now comprises virtually all the farmed oysters in New Zealand.

  3. Electronic voting systems

    Ødegård, Rune Steinsmo

    2006-01-01

    We present the cryptographic primitives needed in the construction of electronic voting systems based on homomorphic encryptions and on verifiable secret sharing. Then "The theory and implementation of an electronic voting system" by Ivan Damgård, Jens Groth and Gorm Salomonsen is presented as an example of electronic voting systems based on homomorphic encryptions, while "Multi-authority secret-ballot election with linear work" by Ronald Cramer, Matthew Franklin, Be...

  4. Effect of hydraulic loading rate on the efficiency of effluent treatment in a recirculating puffer aquaculture system coupled with constructed wetlands

    Xu, Jiabo; Shi, Yonghai; Zhang, Genyu; Liu, Jianzhong; Zhu, Yazhu

    2013-11-01

    Constructed wetlands (CWs) were integrated into an indoor recirculating aquaculture system of obscure puffer (Takifugu obscurus) for effluent treatment. The effect of hydraulic loading rate (HLR) on the efficiency of effluent treatment by CWs was examined for over a month. The CWs were operated under brackish conditions (salinity 7.4-7.6) at 3 different HLRs (0.762, 0.633, and 0.458 m d-1) 3 times, 10 days each. Overall, the CWs exhibited high efficiency in removal of total ammonium nitrogen (by 81.03-92.81%) and nitrite nitrogen (by 99.40%-99.68%). The efficiency of CWs in removal of total ammonium nitrogen, nitrate nitrogen, total Kjeldahl nitrogen, total phosphorous, and total suspended solids (TSS) increased with the decrease of HLR. The CWs operated at the 3 HLRs in a decreasing trend proves to be effective, providing a useful method for effluent treatment in commercial puffer aquaculture systems.

  5. Trophic structure in a pilot system for the integrated multi-trophic aquaculture off the east coast of Korean peninsula as determined by stable isotopes.

    Park, Hyun Je; Han, Eunah; Lee, Won Chan; Kwak, Jung Hyun; Kim, Hyung Chul; Park, Mi Seon; Kang, Chang-Keun

    2015-06-15

    To assess the potential for nutritional exploitation of caged-fish-derived waste through the use of extractive co-cultured species in a pilot system for an integrated multi-trophic aquaculture (IMTA), we compared their C and N stable isotope ratios with those of uncultured macroinvertebrates in and around the system. Black rockfish were co-cultured with sea cucumber, oyster, and two macroalgae as extractive species. Isotope signatures of the co-cultured sea cucumber at the IMTA site differed from those at the control site, indicating their assimilation of aquaculture wastes. In contrast, δ(13)C and δ(15)N of individual taxa of the cultured oyster and uncultured invertebrates were consistent between sites, suggesting a minor contribution of the aquaculture waste to benthic and pelagic food chains in and around the IMTA system. These results provide evidence of the suitability of using sea cucumber as an extractive species to reduce the impact of a monoculture system on the ambient environment. PMID:25916198

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

    Trang, Ngo Thuy Diem; Schierup, Hans-Henrik; Brix, Hans

    2010-01-01

    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...

  7. Electronic theodolite intersection systems

    Bingley, R. M.

    1990-01-01

    The development of electronic surveying instruments, such as electronic theodolites, and concurrent advances in computer technology, has revolutionised engineering surveying; one of the more recent examples being the introduction of Electronic Theodolite Intersection Systems (ETISs). An ETIS consists of two or more electronic theodolites and a computer, with peripheral hardware and suitable software. The theoretical principles on which they are based have been known for a long time, but ...

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

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

    2015-01-01

    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.

  9. Effects of solid-phase denitrification on the nitrate removal and bacterial community structure in recirculating aquaculture system.

    Qiu, Tianlei; Liu, Lili; Gao, Min; Zhang, Lanhe; Tursun, Haireti; Wang, Xuming

    2016-06-01

    A solid-phase denitrification (SPD) reactor packed with poly (3-hydroxybutyrate-co-3-hydroxyvalerate) as a carbon source was incorporated into a recirculating aquaculture system (RAS) to remove accumulated nitrate. Bacterial community structures in different parts of the RAS, including biofilter unit, SPD reactor, and culture water, were analyzed using Illumina MiSeq sequencing technology. The data showed that nitrate levels decreased remarkably in the RAS connected with SPD reactor (RAS-DR). In contrast, nitrate levels increased continuously in the conventional RAS without SPD reactor (RAS-CK). Biofilter unit and culture water in RAS-DR developed lower species richness and higher bacterial community diversity than that in RAS-CK. The bacterial community structure of RAS was significantly affected by the SPD process and the changes included an increase in the proportion of Proteobacteria and Firmicutes and a decrease in Nitrospira abundance in RAS-DR. Firmicutes was the most abundant phylum (56.9 %) and mainly consisted of Clostridium sensu stricto (48.3 %) in SPD reactor. PMID:27125529

  10. Hydrogen peroxide decomposition kinetics in aquaculture water

    Arvin, Erik; Pedersen, Lars-Flemming

    2015-01-01

    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...... 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...

  11. Importance of kelp-derived organic carbon to the scallop Chlamys farreri in an integrated multi-trophic aquaculture system

    Xu, Qiang; Gao, Fei; Yang, Hongsheng

    2015-10-01

    Bivalves and seaweeds are important cleaners that are widely used in integrated multi-trophic aquaculture (IMTA) systems. A beneficial relationship between seaweed and bivalve in the seaweedbased IMTA system has been confirmed, but the trophic importance of seaweed-derived particulate organic materials to the co-cultured bivalve is still unclear. We evaluated the trophic importance of the kelp Saccharina japonica to the co-cultured scallop Chlamys farreri in a typical IMTA farm in Sungo Bay (Weihai, North China). The dynamics of detritus carbon in the water were monitored during the culturing period. The proportion of kelp-derived organic matter in the diet of the co-cultured scallop was assessed via the stable carbon isotope method. Results showed that the detritus carbon in the water ranged from 75.52 to 265.19 ?g/L, which was 25.6% to 73.8% of total particulate organic carbon (TPOC) during the study period. The amount of detritus carbon and its proportion in the TPOC changed throughout the culture cycle of the kelp. Stable carbon isotope analysis showed that the cultured scallop obtained 14.1% to 42.8% of its tissue carbon from the kelp, and that the percentages were closely correlated with the proportion of detritus carbon in the water (F=0.993, P=0.003). Evaluation showed that for 17 000 tons (wet weight) of annual scallop production, the kelp contributed about 139.3 tons of carbon (535.8 tons of dry mass). This confirms that cultured kelp plays a similar trophic role in IMTA systems as it does in a natural kelp bed. It is a major contributor to the detritus pool and supplies a vital food source to filter-feeding scallops in the IMTA system, especially during winter and early spring when phytoplankton are scarce.

  12. Importance of kelp-derived organic carbon to the scallop Chlamys farreri in an integrated multi-trophic aquaculture system

    Xu, Qiang; Gao, Fei; Yang, Hongsheng

    2016-03-01

    Bivalves and seaweeds are important cleaners that are widely used in integrated multi-trophic aquaculture (IMTA) systems. A beneficial relationship between seaweed and bivalve in the seaweed-based IMTA system has been confirmed, but the trophic importance of seaweed-derived particulate organic materials to the co-cultured bivalve is still unclear. We evaluated the trophic importance of the kelp Saccharina japonica to the co-cultured scallop Chlamys farreri in a typical IMTA farm in Sungo Bay (Weihai, North China). The dynamics of detritus carbon in the water were monitored during the culturing period. The proportion of kelp-derived organic matter in the diet of the co-cultured scallop was assessed via the stable carbon isotope method. Results showed that the detritus carbon in the water ranged from 75.52 to 265.19 μg/L, which was 25.6% to 73.8% of total particulate organic carbon (TPOC) during the study period. The amount of detritus carbon and its proportion in the TPOC changed throughout the culture cycle of the kelp. Stable carbon isotope analysis showed that the cultured scallop obtained 14.1% to 42.8% of its tissue carbon from the kelp, and that the percentages were closely correlated with the proportion of detritus carbon in the water ( F =0.993, P= 0.003). Evaluation showed that for 17 000 tons (wet weight) of annual scallop production, the kelp contributed about 139.3 tons of carbon (535.8 tons of dry mass). This confirms that cultured kelp plays a similar trophic role in IMTA systems as it does in a natural kelp bed. It is a major contributor to the detritus pool and supplies a vital food source to filter-feeding scallops in the IMTA system, especially during winter and early spring when phytoplankton are scarce.

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

    Aeknarin Thanakitpairin

    2014-01-01

    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.

  14. Performance of Nile tilapia Oreochromis niloticus fingerlings in a hyper-intensive recirculating aquaculture system with low water exchange

    M Gullian-Klanian

    2013-03-01

    Full Text Available 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.

  15. Nitrogen removal techniques in aquaculture for a sustainable production

    Crab, R.; Avnimelech, Y.; Defoirdt, T; Bossier, P; Verstraete, W

    2007-01-01

    As the aquaculture industry intensively develops, its environmental impact increases. Discharges from aquaculture deteriorate the receiving environment and the need for fishmeal and fish oil for fish feed production increases. Rotating biological contactors, trickling filters, bead filters and fluidized sand biofilters are conventionally used in intensive aquaculture systems to remove nitrogen from culture water. Besides these conventional water treatment systems, there are other possible mod...

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

    Pungrasmi, Wiboonluk; Playchoom, Cholticha; Powtongsook, Sorawit

    2013-08-01

    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

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

    Dam, van, P.H.A.

    1995-01-01

    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...

  18. MUNICIPAL WASTEWATER AQUACULTURE

    The developmental status of the aquacultural alternative for treatment and reuse of municipal wastewater is reviewed. Major emphasis is given to the reduction or fate of pollutants in such areas as organics, solids, nutrients, heavy metals, residual hydrocarbons, and potentially ...

  19. Microalgae for aquaculture

    Michels, M.H.A.

    2015-01-01

    In 2007, the project ‘Zeeuwse Tong’ (Zeeland Sole) was founded with support of the province of Zeeland, the Netherlands. The aim of the Zeeuwse Tong project was to establish an innovative land-based integrated multi-trophic aquaculture sector, which is producing sole, ragworms, algae, shellfish and saline crops in close harmony with nature. The project was divided into two sub-projects: The integrated saline aquaculture farm and the integrated nursery. The research described in this thesis re...

  20. Electronics circuits and systems

    Bishop, Owen

    2007-01-01

    The material in Electronics - Circuits and Systems is a truly up-to-date textbook, with coverage carefully matched to the electronics units of the 2007 BTEC National Engineering and the latest AS and A Level specifications in Electronics from AQA, OCR and WJEC. The material has been organized with a logical learning progression, making it ideal for a wide range of pre-degree courses in electronics. The approach is student-centred and includes: numerous examples and activities; web research topics; Self Test features, highlighted key facts, formulae and definitions. Each chapter ends with a set

  1. Electronics circuits and systems

    Bishop, Owen

    2011-01-01

    The material in Electronics - Circuits and Systems is a truly up-to-date textbook, with coverage carefully matched to the electronics units of the 2007 BTEC National Engineering and the latest AS and A Level specifications in Electronics from AQA, OCR and WJEC. The material has been organized with a logical learning progression, making it ideal for a wide range of pre-degree courses in electronics. The approach is student-centred and includes: numerous examples and activities; web research topics; Self Test features, highlighted key facts, formulae and definitions. Ea

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

    Vu, Minh Thi Thuy; Øie, Gunvor; Reinertsen, Helge

    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...... 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....

  3. 2-Methylisoborneol and geosmin uptake by organic sludge derived from a recirculating aquaculture system.

    Guttman, Lior; van Rijn, Jaap

    2009-02-01

    In a previous study on a recirculating fish culture system, levels of geosmin and 2-methylisoborneol were found to decrease when culture water was recirculated through the anaerobic sludge digestion treatment stage of the system. This finding led us to the present study in which the geosmin and 2-methylisoborneol removal capacity of the sludge derived from this treatment stage was examined in vitro. It was found that reduction of off-flavor compounds by the sludge was mediated by both chemical/physical sorption and biological degradation. At geosmin and 2-methylisoborneol concentrations within the range of those experienced in fish culture systems, chemical/physical sorption by the sludge was found to account for a 93% reduction in geosmin and a 79% reduction in 2-methylisoborneol from the overlying water within 48h of incubation. Combined with the biological degradation taking place in the sludge, a complete removal of these compounds from the water phase occurred within 9 days of incubation. By means of repeated washing of the geosmin and 2-methylisoborneol contaminate sludge with clean water, relatively small amounts of these compounds were released from the sludge, a possible indication for the fact that absorption, rather than adsorption, underlies the chemical/physical removal process. PMID:18986667

  4. Fuzzy logic based control system for fresh water aquaculture: A MATLAB based simulation approach

    Rana Dinesh Singh

    2015-01-01

    Full Text Available Fuzzy control is regarded as the most widely used application of fuzzy logic. Fuzzy logic is an innovative technology to design solutions for multiparameter and non-linear control problems. One of the greatest advantages of fuzzy control is that it uses human experience and process information obtained from operator rather than a mathematical model for the definition of a control strategy. As a result, it often delivers solutions faster than conventional control design techniques. The proposed system is an attempt to apply fuzzy logic techniques to predict the stress factor on the fish, based on line data and rule base generated using domain expert. The proposed work includes a use of Data acquisition system, an interfacing device for on line parameter acquisition and analysis, fuzzy logic controller (FLC for inferring the stress factor. The system takes stress parameters on the fish as inputs, fuzzified by using FLC with knowledge base rules and finally provides single output. All the parameters are controlled and calibrated by the fuzzy logic toolbox and MATLAB programming.

  5. Aquaculture in Sweden : Sustainability of land-based recirculation aquaculture as a future alternative for Swedish fish farmers

    van der Blom, Daan Wilhelmus

    2013-01-01

    With the world’s population expanding rapidly and estimated to reach nine billion in 2050, the demand for food will increase. Therefore the need for more sustainable ways of food production, in particular meat, poultry and fish are needed. Aquaculture can significantly contribute to this. This thesis focuses on Swedish aquaculture and in particular the increasingly used method of food fish farming in Recirculation Aquaculture Systems (RAS). The aim of the thesis is to analyze and discern the ...

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

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

    2007-01-01

    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. Alt...

  7. Electronic components and systems

    Dennis, W H

    2013-01-01

    Electronic Components and Systems focuses on the principles and processes in the field of electronics and the integrated circuit. Covered in the book are basic aspects and physical fundamentals; different types of materials involved in the field; and passive and active electronic components such as capacitors, inductors, diodes, and transistors. Also covered in the book are topics such as the fabrication of semiconductors and integrated circuits; analog circuitry; digital logic technology; and microprocessors. The monograph is recommended for beginning electrical engineers who would like to kn

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

    Pedersen, Lars-Flemming

    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...

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

    Savin Cristian

    2013-01-01

    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.

  10. The effect of temperature and pH on the growth and physiological response of juvenile yellowtail kingfish Seriola lalandi in recirculating aquaculture systems

    Abbink, W.; A.B. Garcia; Roques, J.A.C.; Partridge, G.J.; Kloet, K.; Schneider, O.

    2012-01-01

    A search for a viable new fish species for culture in recirculating aquaculture systems (RAS) in the Netherlands identified yellowtail kingfish Seriola lalandi as having excellent potential. To assist in determining the most appropriate water quality conditions for this species in RAS, the effect of water temperature (21, 23.5, 25, 26.5 and 29 °C) and pH (6.58, 7.16 and 7.85) was tested in two separate experiments. Growth performance, feed conversion, stress-physiological and metabolic parame...

  11. Production Characteristics and Changes in Fatty Acids Profiles of Nile Tilapia (Oreochromis niloticus) Using Algae as a Food Source in Partitioned Aquaculture System

    TEPE, Alp Yalç?n

    2005-01-01

    Small (57.56 ± 0.03 g) and large (172.46 ± 1.14 g) Nile tilapia fingerlings (Oreochromis niloticus) were stocked in six 0.15 ha partitioned aquaculture system (PAS) units on May 1 1997 at a rate of 100 kg/0.15 ha (low density) and 200 kg/0.15 ha (high density) in triplicate to determine the growth rates and production characteristics and the changes in fatty acid profiles of the fish. The primary food source for the 152-day rearing period available to the fish confined within the raceway sect...

  12. Handbook for aquaculture water quality

    Efficient aquaculture production depends upon maintaining acceptable water quality conditions in culture units. This handbook discusses background information from chemistry, physics, biology, and engineering necessary for understanding the principles of water quality management in aquaculture. It a...

  13. Criterios hidrodinámicos para el diseño de sistemas de recirculación en acuicultura / Hydrodynamic Criteria to Design Water Recirculation Systems for Aquaculture

    Juan A., García-Aragón; Humberto, Salinas-Tapia; Víctor, Díaz-Palomarez; Boris M., López-Rebollar; Javier, Moreno-Guevara; Leonarda M., Flores-Gutiérrez.

    2014-10-01

    Full Text Available Con el objetivo de hacer más eficiente el uso del agua se ha desarrollado la técnica de sistemas cerrados de recirculación de agua (SRA) para acuicultura. Un aspecto que se ha relegado, en cuanto a los estudios de calidad de agua y biológicos, es el relativo a la hidrodinámica de esos tanques de rec [...] irculación. En este trabajo se describe una investigación experimental llevada a cabo en un modelo en plexiglass a escala reducida de dichos tanques de recirculación. En un tanque circular se utilizó comida para peces; los flóculos resultantes sirvieron de trazadores para establecer las características de sedimentación. Por medio de técnicas ópticas, velocimetría por imágenes de partículas (PIV), se pudo determinar una distribución óptima de difusores para lograr diferentes velocidades en el tanque, a fin de facilitar los procesos de floculación y, a su vez, los de sedimentación. Igualmente se propone un diseño del sedimentador central en función de las características de los flóculos y de su comportamiento hidrodinámico, en especial su velocidad de caída. Para calcular las velocidades de caída de los flóculos se utilizó la técnica de velocimetría por rastreo de partículas (PTV). Los resultados experimentales permitieron calibrar un modelo matemático de velocidades de caída de flóculos. Abstract in english Closed water recirculation systems (WRS) have been developed for aquaculture in order to more efficiently use water. In terms of water quality and biological studies, the hydrodynamics of recirculation tanks is an aspect that has been least studied. The work herein describes an experimental investig [...] ation carried out with a reduced-scale plexiglass model of these tanks. Fish food was used in one tank in which the resulting flocs served as tracers to determine sedimentation characteristics. Using optical techniques ¾ particle image velocimetry (PIV)¾ it was possible to determine the optimal distribution of diffusers to obtain different velocities in the tank in order to facilitate the flocculation and sedimentation processes. A design for a central settling basin is also proposed based on the characterization of the flocs and their hydrodynamic behavior, particularly the fall velocity. Particle trace velocimetry (PTV) was used to calculate the fall velocity of the flocs. The experimental results enabled calibrating a mathematical model for fall velocities of flocs.

  14. PROTEOMICS in aquaculture

    Rodrigues, Pedro M.; Silva, Tomé S.; Dias, Jorge; Jessen, Flemming

    2012-01-01

    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...

  15. Electron beam processing system

    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)

  16. Certify Sustainable Aquaculture?

    Bush, Simon; Belton, Ben; Hall, Derek; Vandergeest, Peter; Murray, Francis J.; Ponte, Stefano; Oosterveer, Peter; Islam, Muhammad Saidul; Mol, Arthur P. J.; Hatanaka, Maki; Kruijssen, Froukje; Ha, Tran Thi Thu; Little, David C.; Kusumawati, Rini

    2013-01-01

    Aquaculture, the farming of aquatic organisms, provides close to 50% of the world's supply of seafood, with a value of U.S. $125 billion. It makes up 13% of the world's animal-source protein (excluding eggs and dairy) and employs an estimated 24 million people (1). With capture (i.e., wild......) fisheries production stagnating, aquaculture may help close the forecast global deficit in fish protein by 2020 (2). This so-called “blue revolution” requires addressing a range of environmental and social problems, including water pollution, degradation of ecosystems, and violation of labor standards....

  17. Certify Sustainable Aquaculture?

    Bush, Simon; Belton, Ben; Hall, Derek; Vandergeest, Peter; Murray, Francis J.; Ponte, Stefano; Oosterveer, Peter; Islam, Muhammad Saidul; Mol, Arthur P. J.; Hatanaka, Maki; Kruijssen, Froukje; Ha, Tran Thi Thu; Little, David C.; Kusumawati, Rini

    2013-01-01

    ) fisheries production stagnating, aquaculture may help close the forecast global deficit in fish protein by 2020 (2). This so-called “blue revolution” requires addressing a range of environmental and social problems, including water pollution, degradation of ecosystems, and violation of labor standards.......Aquaculture, the farming of aquatic organisms, provides close to 50% of the world's supply of seafood, with a value of U.S. $125 billion. It makes up 13% of the world's animal-source protein (excluding eggs and dairy) and employs an estimated 24 million people (1). With capture (i.e., wild...

  18. MDT DCS Electronics System

    Tsarouchas, Charilaos; Gazis, Evangelos; Tsipolitis, Georgios

    This note has the aim to present the Detector Control System for the Monitor- ing of the electronics values of MDT chambers in ATLAS experiment in CERN. This system is decided to be called in short ELTX. The principal task of DCS is to enable and ensure the coherent and safe oper- ation of the detector. The interaction of detector expers, users or shifters to the detector hardware is also done via DCS. This is the responsible system of moni- toring the operational parameters and the overall state of the detector, the alarm generation and handling, the connection of hardware values to databases and the interaction with the DAQ system. Through this thesis, one can see what ELTX system has to offer as a Detector Control System and in detail, what is the hardware to be controlled and monitored. Moreover it is presented the mainstream of central Atlas DCS concerning the active interfaces.ELTX is a system following these standards.

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

    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 w...

  20. Electron-electron interactions in disordered systems

    Efros, AL

    1985-01-01

    ``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.

  1. Hydrogen peroxide decomposition kinetics in aquaculture water

    Arvin, Erik; Pedersen, Lars-Flemming

    2015-01-01

    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...... 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...

  2. Confinement Aquaculture. Final Report.

    Delaplaine School District, AR.

    The Delaplaine Agriculture Department Confinement Project, begun in June 1988, conducted a confinement aquaculture program by comparing the growth of channel catfish raised in cages in a pond to channel catfish raised in cages in the Black River, Arkansas. The study developed technology that would decrease costs in the domestication of fish, using…

  3. Aquaculture. Teacher Edition.

    Walker, Susan S.

    This color-coded guide was developed to assist teachers in helping interested students plan, build, stock, and run aquaculture facilities of varied sizes. The guide contains 15 instructional units, each of which includes some or all of the following basic components: objective sheet, suggested activities for the teacher, instructor supplements,…

  4. Aquacultural Occupational Task Analysis.

    Dung, Elaine; Wakui, Lawrence S.

    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…

  5. Background paper on aquaculture research

    Wenblad, Axel; Jokumsen, Alfred; Eskelinen, Unto; Torrissen, Ole

    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...

  6. Cooling system for electronic components

    Anderl, William James; Colgan, Evan George; Gerken, James Dorance; Marroquin, Christopher Michael; Tian, Shurong

    2015-12-15

    Embodiments of the present invention provide for non interruptive fluid cooling of an electronic enclosure. One or more electronic component packages may be removable from a circuit card having a fluid flow system. When installed, the electronic component packages are coincident to and in a thermal relationship with the fluid flow system. If a particular electronic component package becomes non-functional, it may be removed from the electronic enclosure without affecting either the fluid flow system or other neighboring electronic component packages.

  7. Cooling system for electronic components

    Anderl, William James; Colgan, Evan George; Gerken, James Dorance; Marroquin, Christopher Michael; Tian, Shurong

    2016-05-17

    Embodiments of the present invention provide for non interruptive fluid cooling of an electronic enclosure. One or more electronic component packages may be removable from a circuit card having a fluid flow system. When installed, the electronic component packages are coincident to and in a thermal relationship with the fluid flow system. If a particular electronic component package becomes non-functional, it may be removed from the electronic enclosure without affecting either the fluid flow system or other neighboring electronic component packages.

  8. Genomic approaches in aquaculture and fisheries

    Cancela, M. Leonor; Bargelloni, Luca; Boudry, Pierre; Boulo, Viviane; Dias, Jorge; Huvet, Arnaud; Laize, Vincent; Lapegue, Sylvie; Leite, Ricardo; Mira, Sara; Eg Nielsen, Einar; Planas, Josep V.; Roher, Nerea; Sarropoulou, Elena; Volckaert, Filip A. M.; Cock, JM; TessmarRaible, K; Boyen, C; Viard, F

    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...

  9. Sustainability in aquaculture

    Surtida, M.B.

    1998-01-01

    Sustainable aquaculture in Asia is discussed, considering in particular the loss of mangroves associated with the rapid increase in production of cultured shrimp. Southeast Asia's development and population growth brought non-sustainable exploitation of its coastline; the destruction has increased through the years as development proceeded and the international markets entered the scenario. An outline is given of the current status of mangroves in some Asian countries. Some worldwide remedies...

  10. Marketing Netcoatings for Aquaculture

    Martin, Robert J.

    2014-01-01

    Unsustainable harvesting of natural fish stocks is driving an ever growing marine aquaculture industry. Part of the aquaculture support industry is net suppliers who provide producers with nets used in confining fish while they are grown to market size. Biofouling must be addressed in marine environments to ensure maximum product growth by maintaining water flow and waste removal through the nets. Biofouling is managed with copper and organic biocide based net coatings. The aquaculture industry provides a case study for business issues related to entry of improved fouling management technology into the marketplace. Several major hurdles hinder entry of improved novel technologies into the market. The first hurdle is due to the structure of business relationships. Net suppliers can actually cut their business profits dramatically by introducing improved technologies. A second major hurdle is financial costs of registration and demonstration of efficacy and quality product with a new technology. Costs of registration are prohibitive if only the net coatings market is involved. Demonstration of quality product requires collaboration and a team approach between formulators, net suppliers and farmers. An alternative solution is a vertically integrated business model in which the support business and product production business are part of the same company. PMID:25329615

  11. Comparing the effects of feeding a grain- or a fish meal-based diet on water quality, waste production, and rainbow trout Oncorhynchus mykiss performance within low exchange water recirculating aquaculture systems

    Feeding a fish meal-free grain-based diet (GB) was compared to feeding a fish meal-based diet (FM) relative to water quality criteria, waste production, water treatment process performance, and rainbow trout Oncorhynchus mykiss performance within six replicated water recirculating aquaculture system...

  12. Reduced photoperiod (18 h light vs 24 h light) during first-year rearing associated with increased early male maturation in Atlantic salmon Salmo salar cultured in a freshwater recirculation aquaculture system

    Early male sexual maturation in Atlantic salmon Salmo salar is undesirable for a number of reasons related to production efficiency, and it appears that precocious maturation is a particular problem when raising this species to market size in water recirculation aquaculture systems (RAS). We investi...

  13. Application of a fluidized bed reactor charged with aragonite for control of alkalinity, pH and carbon dioxide in marine recirculating aquaculture systems

    Paul S Wills, PhD; Pfeiffer, Timothy; Baptiste, Richard; Watten, Barnaby J.

    2016-01-01

    Control of alkalinity, dissolved carbon dioxide (dCO2), and pH are critical in marine recirculating aquaculture systems (RAS) in order to maintain health and maximize growth. A small-scale prototype aragonite sand filled fluidized bed reactor was tested under varying conditions of alkalinity and dCO2 to develop and model the response of dCO2 across the reactor. A large-scale reactor was then incorporated into an operating marine recirculating aquaculture system to observe the reactor as the system moved toward equilibrium. The relationship between alkalinity dCO2, and pH across the reactor are described by multiple regression equations. The change in dCO2 across the small-scale reactor indicated a strong likelihood that an equilibrium alkalinity would be maintained by using a fluidized bed aragonite reactor. The large-scale reactor verified this observation and established equilibrium at an alkalinity of approximately 135 mg/L as CaCO3, dCO2 of 9 mg/L, and a pH of 7.0 within 4 days that was stable during a 14 day test period. The fluidized bed aragonite reactor has the potential to simplify alkalinity and pH control, and aid in dCO2 control in RAS design and operation. Aragonite sand, purchased in bulk, is less expensive than sodium bicarbonate and could reduce overall operating production costs.

  14. INSENTIF EKONOMI TERHADAP USAHA AQUACULTURE

    Mira Mira

    2012-01-01

    The purpose of this study is to analyze the incentives for aquaculture businesses, one of these efforts is seaweed in Bone, South Sulawesi. Government intervention to develop the aquaculture business can be seen from the incentives provided. Incentives can be subsidized (at nursery) or in the form of protection (when the product is sold in the market). Incentives provided by the government in the form of policies, pay tax breaks or subsidies, have not touched this aquaculture business effecti...

  15. Background paper on aquaculture research

    Wenblad, Axel; Jokumsen, Alfred; Eskelinen, Unto; Torrissen, Ole

    2013-01-01

    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 ...

  16. Direct utilization of geothermal heat in cascade application to aquaculture and greenhouse systems at Navarro College. Final report, March 1, 1979-September 30, 1984

    Smith, K.

    1984-09-01

    This final report documents the Navarro College geothermal use project, which is one of nineteen direct-use geothermal projects funded principally by DOE. The six-year project encompassed a broad range of technical, institutional, and economic activities including: resource and environmental assessment; well drilling and completion; system design, construction, and monitoring; economic analysis; and public awareness programs. Some of the project conclusions are that: (1) the 130/sup 0/F Central Texas geothermal resource can support additional geothermal development; (2) private sector economic incentives currently exist which encourage commercial development of this geothermal resource; (3) potential uses for this geothermal resource include water and space heating, aquacultural and agricultural heating uses, and fruit and vegetable dehydration; (4) high maintenance costs arising from the geofluids' scaling and corrosion characteristics can be avoided through proper analysis and design.

  17. Evaluation of feed and feeding regime on growth performance, flesh quality and fecal viscosity of Atlantic salmon ( Salmo salar L.) in recirculating aquaculture systems

    Sun, Guoxiang; Liu, Ying; Li, Yong; Li, Xian; Wang, Shunkui

    2015-10-01

    The effects of different feeds and feeding regimes on growth performance, flesh quality and fecal viscosity of Atlantic salmon ( Salmo salar L.) in recirculating aquaculture systems (RAS) were investigated. Fish (initial body weight of 1677 g ± 157 g) were fed with four commercial feeds (Nosan salmon-NS, Aller gold-AG, Skretting salmon-SS and Han ye-HY) in two feeding regimes (80% and 100% satiation) for 78 d. The results showed that salmon specific growth ratio (SGR) and weight gain ratio (WGR) were significantly affected by feed type and feeding regime ( P activities of digestive enzymes including protease, lipase and amylase were also significantly affected by feed type and feeding regime ( P pH among all groups showed significant differences ( P experiment, it was concluded that both feed type and feeding regime can affect the important quality attributes of Atlantic salmon.

  18. Literature review of the potential effects of hydrogen peroxide on nitrogen oxidation efficiency of the biofilters of recirculating aquaculture systems (RAS) for freshwater finfish

    Fredricks, Kim T.

    2015-01-01

    A comprehensive literature review was done for the effects of hydrogen peroxide (HP) on biofilter function in recirculating aquaculture systems (RAS) using these databases: ISI/Web of Knowledge, Scopus, and Pubmed. Inclusion and exclusion criteria were developed as the literature review was conducted. The initial search produced 5,748 potential citations. Once the literature search was complete, these 5,748 titles were screened for applicable papers using the inclusion and exclusion criteria. If the title contained any of the inclusion terms, it was retained. Titles of the remaining papers were then screened for exclusion terms. If the title contained one or more of the exclusion terms, it was eliminated from further consideration. This refined search produced 1,405 papers.

  19. 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

    Desimira Maria Dicu Stroe

    2013-10-01

    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

  20. Nitrous oxide (N2O) emission from aquaculture: a review.

    Hu, Zhen; Lee, Jae Woo; Chandran, Kartik; Kim, Sungpyo; Khanal, Samir Kumar

    2012-06-19

    Nitrous oxide (N(2)O) is an important greenhouse gas (GHG) which has a global warming potential 310 times that of carbon dioxide (CO(2)) over a hundred year lifespan. N(2)O is generated during microbial nitrification and denitrification, which are common in aquaculture systems. To date, few studies have been conducted to quantify N(2)O emission from aquaculture. Additionally, very little is known with respect to the microbial pathways through which N(2)O is formed in aquaculture systems. This review suggests that aquaculture can be an important anthropogenic source of N(2)O emission. The global N(2)O-N emission from aquaculture in 2009 is estimated to be 9.30 × 10(10) g, and will increase to 3.83 × 10(11)g which could account for 5.72% of anthropogenic N(2)O-N emission by 2030 if the aquaculture industry continues to increase at the present annual growth rate (about 7.10%). The possible mechanisms and various factors affecting N(2)O production are summarized, and two possible methods to minimize N(2)O emission, namely aquaponic and biofloc technology aquaculture, are also discussed. The paper concludes with future research directions. PMID:22594516

  1. Heterotrophic denitrification of aquaculture effluent using fluidized sand biofilters

    The ability to consistently and cost-effectively reduce nitrate-nitrogen loads in effluent from recirculating aquaculture systems would enhance the industry's environmental stewardship and allow improved facility proximity to large markets in sensitive watersheds. Heterotrophic denitrification techn...

  2. Aquaculture. Second Edition. Teacher Edition.

    Walker, Susan S.; Crummett, Dan

    This teacher and student guide for aquaculture contains 15 units of instruction that cover the following topics: (1) introduction to aquaculture; (2) the aquatic environment; (3) fundamental fish biology; (4) marketing; (5) site selection; (6) facility design and layout; (7) water quality management; (8) fish health management; (9) commercial…

  3. Reliability of electronic systems

    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 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)

  4. Nutrients valorisation via Duckweed-based wastewater treatment and aquaculture

    Mohamed El-Shafai, S.A.A.

    2004-01-01

    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 temperature in winter...

  5. Nutrients valorisation via duckweed-based wastewater treatment and aquaculture

    El-Shafai, S.A.A.M.

    2004-01-01

    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 temperat...

  6. Optimizing nitrate removal in woodchip beds treating aquaculture effluents

    von Ahnen, Mathis; Pedersen, Per Bovbjerg; Hoffmann, Carl Christian; Dalsgaard, Anne Johanne Tang

    2016-01-01

    Nitrate is typically removed from aquaculture effluents using heterotrophic denitrification reactors. Heterotrophic denitrification reactors, however, require a constant input of readily available organic carbon (C) sources which limits their application in many aquaculture systems for practical...... potential of optimizing woodchip reactors for treating aquaculture effluent. A central composite design (CCD) was applied to assess the effects of simultaneously changing the empty bed contact time (EBCTs of 5.0-15.0 h; corresponding to theoretical hydraulic retention times of 3.3-9.9 h) and bicarbonate...... (HCO3 -) inlet concentration (0.50-1.59 g HCO3 -/l) on the removal rate of NO3 -N, and additional organic and inorganic nutrients, in effluent deriving from an experimental recirculating aquaculture system (RAS).Volumetric NO3 -N removal rates ranged from 5.20 ± 0.02 to 8.96 ± 0.19 g/m3/day and were...

  7. [Electronic poison information management system].

    Kabata, Piotr; Waldman, Wojciech; Kaletha, Krystian; Sein Anand, Jacek

    2013-01-01

    We describe deployment of electronic toxicological information database in poison control center of Pomeranian Center of Toxicology. System was based on Google Apps technology, by Google Inc., using electronic, web-based forms and data tables. During first 6 months from system deployment, we used it to archive 1471 poisoning cases, prepare monthly poisoning reports and facilitate statistical analysis of data. Electronic database usage made Poison Center work much easier. PMID:24466697

  8. Use of antimicrobial agents in aquaculture.

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

    2012-04-01

    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

  9. Japanese aquaculture with thermal water from power plants

    The present level of thermal aquaculture, utilizing thermal water which is waste cooling water from nuclear power plant, in Japan is reported. There are 13 major potential areas for thermal aquaculture in cooperation with conventional type thermal power plants, seven of which are actually operating. Aquaculture facilities of all these are on land, none in the sea. Of these seven centers, those that have already commercialized their nursery methods or are approaching that stage of research and development, are Tohoku Hatsuden Kogyo Ltd., Tsuruga Hama Land Ltd. and Kyushu Rinsan Ltd. Major problems faced specialists in Japanese thermal aquaculture are water temperature, water quality, radioactivity and costs. For keeping the water temperature constant all seasons, cooling or heating by natural sea water may be used. Even negligible amounts of radioactivity that nuclear power plants release into the sea will concentrate in the systems of marine life. A strict precautionary checking routine is used to detect radioactivity in marine life. (Kobatake, H.)

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

    Cranford, P.J.; Kamermans, P.; Krause, G.H.M.; Mazurie, J.

    2012-01-01

    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–en...

  11. 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).

    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

    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

  12. The ALS Gun Electronics system

    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

  13. The ALS gun electronics system

    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

  14. DNA vaccines for aquacultured fish

    Lorenzen, Niels; LaPatra, S.E.

    2005-01-01

    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...

  15. Temperature effects on biomass, geosmin, and 2-methylisoborneol production and cellular activity by Nocardia spp. and Streptomyces spp. isolated from rainbow trout recirculating aquaculture systems.

    Schrader, Kevin K; Harries, Marcuslene D; Page, Phaedra N

    2015-05-01

    Isolates of Nocardia cummidelens, Nocard ia fluminea, Streptomyces albidoflavus, and Streptomyces luridiscabiei attributed as the cause of "earthy-musty" off-flavor in rainbow trout (Oncorhynchus mykiss) raised in recirculating aquaculture systems (RAS) were evaluated for the effect of temperature (10-30 °C) on biomass, geosmin, and 2-methylisoborneol (MIB) production and cellular activity. Cultures of these isolates were monitored over 7 days by measuring culture dry weight, geosmin, and MIB production using solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS), and ATP production via a luminometer. Compared to the other isolates, S. luridiscabiei had significantly (P water temperature in the RAS) after 7 days incubation. In addition, S. luridiscabiei produced significantly (P geosmin (69,976 ± 15,733 ng/L) at 15 °C. At 25 °C and 30 °C, S. albidoflavus produced significantly (P geosmin (182,074 ± 60,272 ng/L and 399,991 ± 102,262 ng/L, respectively). All isolates produced MIB at 15 °C, but S. luridiscabiei produced significantly (P geosmin and MIB in the RAS. PMID:25724337

  16. 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

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

    2004-01-01

    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.

  17. Cost analysis of electronic systems

    Sandborn, Peter

    2012-01-01

    Understanding the cost ramifications of design, manufacturing and life-cycle management decisions is of central importance to businesses associated with all types of electronic systems. Cost Analysis of Electronic Systems contains carefully developed models and theory that practicing engineers can directly apply to the modeling of costs for real products and systems. In addition, this book brings to light and models many contributions to life-cycle costs that practitioners are aware of but never had the tools or techniques to address quantitatively in the past.Cost Analysis of Electronic Syste

  18. A Comparative Economic Evaluation of Farming of three Important Aquaculture Species in Kenya.

    Mbugua, Henry Mwangi

    2007-01-01

    Information on the economic viability of aquaculture is crucial for investors when assessing the feasibility of an aquaculture investment. Unfortunately, such information has been scarce in Kenya. This paper evaluates the viability of commercial culture of three aquaculture species in Kenya under four culture practices. These are: Nile tilapia (Oreochromis niloticus) and African catfish (Clarias gariepinus), mainly produced using mono- or polyculture under semi intensive systems; and rainbow ...

  19. Aquaponics and its potential aquaculture wastewater treatment and human urine treatment

    Sánchez, Henrique Junior Aiveca

    2014-01-01

    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...

  20. Electronic Journal Publishing System - SEER

    R.Martins So da Fonseca; M.Angel Mard Arellano; C.Roberto Meinert; L. Café

    2004-01-01

    The present work describes the adaptation to Portuguese of the Open Journal Systems (OJS), a software applied to the administration of the editorial process of electronic journals, developed by the Public Knowledge Project (PKP), of the University of British Columbia, Canada. The customization resulted in the ELECTRONIC JOURNAL PUBLISHING SYSTEM (SEER), which has become part of the Brazilian Digital Library (BDB) project of the Instituto Brasileiro de Informação em Ciência e Tecnologia (IBICT...

  1. Issues, impacts, and implications of shrimp aquaculture in Thailand

    Dierberg, Forrest E.; Kiattisimkul, Woraphan

    1996-09-01

    Water quality impacts to and from intensive shrimp aquaculture in Thailand are substantial. Besides the surface and subsurface salinization of freshwaters, loadings of solids, oxygen-consuming organic matter, and nutrients to receiving waters are considerable when the cumulative impacts from water exchange during the growout cycle, pond drainage during harvesting, and illegal pond sediment disposal are taken into account. Although just beginning to be considered in Thailand, partial recirculating and integrated intensive farming systems are producing promising, if somewhat limited, results. By providing on-site treatment of the effluent from the shrimp growout ponds, there is less reliance on using outside water supplies, believed to be the source of the contamination. The explosion in the number of intensively operated shrimp farms has not only impacted the coastal zone of Thailand, but has also resulted in an unsustainable aquaculture industry. Abandonment of shrimp ponds due to either drastic, disease-caused collapses or more grandual, year-to-year reductions in the productivity of the pond is common. To move Thailand towards a more sustainable aquaculture industry and coastal zone environment, integrated aquaculture management is needed. Components of integrated aquaculture management are technical and institutional. The technical components involve deployment of wastewater treatment and minimal water-use systems aimed at making aquaculture operations more hydraulically closed. Before this is possible, technical and economic feasibility studies on enhanced nitrification systems and organic solids removal by oxidation between production cycles and/or the utilization of plastic pond liners need to be conducted. The integration of semi-intensive aquaculture within mangrove areas also should be investigated since mangrove losses attributable to shrimp aquaculture are estimated to be between 16 and 32% of the total mangrove area destroyed betweeen 1979 and 1993. Government policy needs to devote as much attention to sustainability issues as it has on promoting intensive pond culture. Such a balanced policy would include training and education monitoring and enforcement, rehabilitating abandoned ponds, managing land use within the coastal zone, more community involvement, and government reorganization to eliminate overlapping jurisdictions among agencies. As integrated aquaculture management becomes more the practice than the exception, less risk of crop failure to the industry and reduced discharge loadings from intensively managed shrimp ponds to receiving waters can be expected. Projected limitations on growing and marketing shrimp in the future, such as scarcity of land and broodstock, continued disease outbreaks, negative publicity, regulatory enforcement, water treatment and solids disposal costs, and increased competition from growers in other Asian countries will also drive the government and the industry towards adopting integrated aquaculture management.

  2. Potential use of power plant reject heat in commercial aquaculture

    Olszewski, M.

    1977-01-01

    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.

  3. Potential use of power plant reject heat in commercial aquaculture

    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

  4. FTU bolometer electronic system upgrade

    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

  5. Component reliability for electronic systems

    Bajenescu, Titu-Marius I

    2010-01-01

    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.

  6. Analytical purpose electron backscattering system

    In this work an analytical purposes electron backscattering system improved at the Center of Applied Studies for Nuclear Development is described. This system can be applied for fast, exact and nondestructive testing of binary and AL/Cu, AL/Ni in alloys and for other applications

  7. Thalassotalea marina sp. nov., isolated from a marine recirculating aquaculture system, reclassification of Thalassomonas eurytherma as Thalassotalea eurytherma comb. nov. and emended description of the genus Thalassotalea.

    Hou, Ting-Ting; Liu, Ying; Zhong, Zhi-Ping; Liu, Hong-Can; Liu, Zhi-Pei

    2015-12-01

    A Gram-stain-negative, facultatively anaerobic bacterium, strain QBLM2T, was isolated from rearing water of a marine recirculating aquaculture system in Tianjin, China. Its taxonomic position was investigated through a polyphasic approach. Cells of strain QBLM2T were non-spore-forming rods, motile by means of a single polar flagellum. Positive for oxidase and catalase. Growth occurred at 15-40?°C (optimum 30?°C), at pH?6.5-10.5 (optimum pH?7.5-8.5) and in the presence of 0-5.0?% (w/v) NaCl (optimum 3?%). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain QBLM2T formed a distinct lineage within the genus Thalassotalea and exhibited sequence similarities of 94.5-96.3?% to members of the genus Thalassotalea. The predominant fatty acids (>10?%) were C17?:?1?8c and summed feature 3 (C16?:?1?7c and/or C16?:?1?6c). The major polar lipids were phosphatidylglycerol and phosphatidylethanolamine. Ubiquinone 8 (Q-8) was the major ubiquinone. The DNA G+C content was 37.1?mol%. Based on the data above, strain QBLM2T is considered to represent a novel species of the genus Thalassotalea, for which the name Thalassotalea marina sp. nov. is proposed. The type strain is QBLM2T (?=?CGMCC 1.12814T?=?KCTC 42731T). Phylogenetic analyses indicated that Thalassomonas eurytherma Za6a-12T fell within the genus Thalassotalea, so it is reclassified as Thalassotalea eurytherma comb. nov. and the description of the genus Thalassotalea is emended. PMID:26400666

  8. THE DEVELOPMENT OF ROMANIAN AQUACULTURE SECTOR

    Florina Oana VÎRLĂNUȚĂ

    2015-12-01

    Full Text Available Aquaculture contribute ever more to the production of aquatic food worldwide, even if the sustainable limits for majority of wild fish stocks, are now almost reached or even exceeded. In the EU, aquaculture is an important economic activity in many coastal and continental regions. Aquaculture plays an important role in terms of access to food resources and it is necessary to use its potential to contribute to sustainable development, food security, economic growth and employment. In this regard, starting from EU aquaculture objectives, we intend to make an analysis of the national situation of aquaculture and its current potential. We will also analyse the progress of Romanian investments in aquaculture, identifying needs and opportunities for Romanian aquaculture development. The conclusions of the research may be useful for academic and business environment, to develop sustainable activities in aquaculture sector.

  9. Aquaculture practices and the coastal marine environment

    Ingole, B.S.; Ansari, Z.A.; Sreepada, R.A.

    Aquaculture has the potential for causing environmental harm as well as for improving livelihood and nutrition. Aquaculture development, therefore requires to be seen in the wider context of aquatic resource use, land use development and its...

  10. INSENTIF EKONOMI TERHADAP USAHA AQUACULTURE

    Mira Mira

    2012-12-01

    Full Text Available The purpose of this study is to analyze the incentives for aquaculture businesses, one of these efforts is seaweed in Bone, South Sulawesi. Government intervention to develop the aquaculture business can be seen from the incentives provided. Incentives can be subsidized (at nursery or in the form of protection (when the product is sold in the market. Incentives provided by the government in the form of policies, pay tax breaks or subsidies, have not touched this aquaculture business effectively. It can be seen from the value of the effectiveness of incentives for a commodity that is less than one (0.67. The government has not provided direct subsidies to farmers, unlike the fishing effort to get direct subsidies in the form of fuel prices (fuel oil are relatively inexpensive for the fishermen. It can be seen from the value of subsidies for farmers who are negative (-0.3.

  11. Realization of dynamical electronic systems

    Hammari Elena

    2014-04-01

    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.

  12. Portable digital electronic radiography system

    Radiography is a standard nondestructive technique in the industrial testing of materials and components. It is routinely used during the construction, maintenance and repair of nuclear plants. Traditionally, radiography is performed using photographic film (film radiography, FR). Recent developments in solid-state area imaging radiation detectors, miniature electronics and computer software/hardware techniques have brought electronic alternatives to FR. In recent years various electronic radiography (ER) techniques have served as alternatives to FR, these proved beneficial in some applications. While originally developed to provide real time imaging, ER may offer other advantages over FR, depending on the application. Work was undertaken at CRL to review progress in ER techniques and evaluate the possibility of constructing a portable DER (digital electronic radiography) system, for the inspection of power plant components. A suitable DER technique has been developed and a proof of principle portable system constructed. As this paper demonstrates, a properly designed ER system can be small and compact, while providing radiographic examination with acceptable image quality and the benefits of ER imaging. The CRL DER system can operate with radioactive sources typical of FR. While it does not replace FR, our DER system is expected to be beneficial in specific applications for Candu maintenance, reducing cost, labour and time. Practical, cost saving applications of this system are expected to include valve monitoring and foreign object location during maintenance at Candu reactors

  13. Applications of probiotic in aquaculture

    Seval Bahadır Koca

    2011-10-01

    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.

  14. Status of Irish Aquaculture 2004

    Institute, Marine; Mhara, Bord Iascaigh; Teo, Taighde Mara

    2005-01-01

    This report is the second annual report on the status of Irish aquaculture (see Parsons et al., 2004). 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 and Taighde Mara. The aims of the report are to: (1) provide an objective and comprehensive source of information on the status of Irish aquaculture in 2004; (2) show the main trends i...

  15. Knowing Asian aquaculture and fisheries. Part 1

    Surtida, M.B.

    1998-01-01

    An outline is given of aquaculture and fisheries in Asia, providing information of use to students whose work can influence laws, rules, policy and regulations on aquaculture and fisheries, with the view in mind to sustainable aquaculture. In this issue, the following countries are examined: China, Indonesia, and Bangladesh.

  16. Increased competition for aquaculture from fisheries

    Jensen, Frank; Nielsen, Max; Nielsen, Rasmus

    2014-01-01

    ; 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....

  17. United States Aquaculture and the Environment

    This is the introductory chapter to the book “Environmental Best Management Practices for Aquaculture.” The chapter broadly focuses on interactions between aquaculture and the environment. The first sections describe global and United States aquaculture, including a detailed summary of U.S. aquacu...

  18. Exploring Aquaculture. Curriculum Guide for Agriscience 282.

    Texas A and M Univ., College Station. Dept. of Agricultural Education.

    This curriculum guide provides materials for teachers to use in developing a course in "Exploring Aquaculture, Agriscience 282," one of 28 semester courses in agricultural science and technology for Texas high schools. This introductory course is designed to acquaint students with the growing industry of aquaculture; it includes aquaculture career…

  19. Performance evaluation of four different methods for circulating water in commercial-scale, split-pond aquaculture systems

    The split-pond consists of a fish-culture basin that is connected to a waste-treatment lagoon by two conveyance structures. Water is circulated between the two basins with high-volume pumps and many different pumping systems are being used on commercial farms. Pump performance was evaluated with fou...

  20. DNA vaccines for aquacultured fish.

    Lorenzen, N; LaPatra, S E

    2005-04-01

    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 fish have 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. PMID:16110889

  1. CRT electron-optical system

    Shirai, Shoji

    1995-09-01

    CRT is the most successful electron optical system, commercially. Over a hundred million systems are produced each year, and distributed to the whole world as television sets or personal computers. Therefore, the system has to be extremely cost and power effective, and ergonomics is the important issue at its design. Also, CRT has to be bright enough to be watched in the luminous living or office room. Therefore, electron beam current and anode voltage (CRT screen voltage) are as high as 0.5 to 7 mA and 20 to 33 kV, respectively. These unique restrictions cause unique electron lens design such as in-line rotationally asymmetrical lens or dynamic quadrupole lens and deflection yoke design such as self converging deflection yoke which produces barrel shaped vertical and pin-cushion shaped horizontal magnetic fields. In this paper the recent technical advancement and future trends of the CRT electron optical system will be discussed. The discussion will be restricted only to the picture tube, and other devices such as camera tube, oscilloscope tube will be excluded.

  2. Tevatron electron lens magnetic system

    Vladimir Shiltsev et al.

    2001-07-12

    In the framework of collaboration between IHEP and FNAL, a magnetic system of the Tevatron Electron Lens (TEL) has been designed and built. The TEL is currently installed in the superconducting ring of the Tevatron proton-antiproton collider and used for experimental studies of beam-beam compensation [1].

  3. DNA vaccines for aquacultured fish

    Lorenzen, Niels; LaPatra, S.E.

    2005-01-01

    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....

  4. Generative electronic background music system

    Mazurowski, Lukasz [Faculty of Computer Science, West Pomeranian University of Technology in Szczecin, Zolnierska Street 49, Szczecin, PL (Poland)

    2015-03-10

    In this short paper-extended abstract the new approach to generation of electronic background music has been presented. The Generative Electronic Background Music System (GEBMS) has been located between other related approaches within the musical algorithm positioning framework proposed by Woller et al. The music composition process is performed by a number of mini-models parameterized by further described properties. The mini-models generate fragments of musical patterns used in output composition. Musical pattern and output generation are controlled by container for the mini-models - a host-model. General mechanism has been presented including the example of the synthesized output compositions.

  5. Generative electronic background music system

    In this short paper-extended abstract the new approach to generation of electronic background music has been presented. The Generative Electronic Background Music System (GEBMS) has been located between other related approaches within the musical algorithm positioning framework proposed by Woller et al. The music composition process is performed by a number of mini-models parameterized by further described properties. The mini-models generate fragments of musical patterns used in output composition. Musical pattern and output generation are controlled by container for the mini-models - a host-model. General mechanism has been presented including the example of the synthesized output compositions

  6. Field reliability of electronic systems

    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)

  7. Power electronic systems Walsh analysis with Matlab

    Deb, Anish

    2014-01-01

    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

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

    Colt, John; Watten, Barnaby; Pfeiffer, Tim

    2012-01-01

    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 (carbon dioxide removal.

  9. PREFACE: Strongly correlated electron systems Strongly correlated electron systems

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

    2012-07-01

    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 K Rößler, A A Leonov and A N Bogdanov Antiferromagnetism in metals: from the cuprate superconductors to the heavy fermion materialsSubir Sachdev, Max A Metlitski and Matthias Punk Superconducting gap structure of the 115s revisitedF Ronning, J-X Zhu, Tanmoy Das, M J Graf, R C Albers, H B Rhee and W E Pickett Nonmagnetic ground states and phase transitions in the caged compounds PrT2Zn20 (T = Ru, Rh and Ir)T Onimaru, K T Matsumoto, N Nagasawa, Y F Inoue, K Umeo, R Tamura, K Nishimoto, S Kittaka, T Sakakibara and T Takabatake New universality class of quantum criticality in Ce- and Yb-based heavy fermionsShinji Watanabe and Kazumasa Miyake

  10. Reproductive engineering in crustacean aquaculture

    Subramoniam, T.

    1988-01-01

    Crustacean aquaculture industry in India suffers greatly from lack of technological developments. A major constraint in this enterprise is the limitation of seed stock availability. A critical appraisal is made of the techniques used in the manipulation of reproductive processes in order to augment year-round production of seeds. A new possibility of induced ovarian maturation in crustaceans is by administering steroid hormones of vertebrate source. Environmental factors are known to govern t...

  11. Training in African aquaculture development

    Brummett, R E

    1994-01-01

    The article focuses on the types of training needed in African aquaculture development. The author suggested that rather than needing less training, extension agents and others who operate in the idiosyncratic world of the poor African farmer, need a far deeper understanding of fish culture (particularly the basics of pond dynamics and ecology) than do those who can take advantage of industrialized-country infrastructure.

  12. Importance of Prebiotic in Aquaculture

    Arzu Özlüer-Hunt; Ferbal Özkan-Yılmaz; Mükerrem Çetinkaya

    2015-01-01

    The world aquaculture industry shows a rapid increase in production recently. Depending on production methods, culture techniques and culture methods are also developing. With developing culture methods, decrease of water quality, increase of stress, decrease of food quality, increase bacterial, viral or parasite infections can suppress on growth. Lately the use of alternative materials such as prebiotics widespread to improve the health of the fish. A prebiotic is a non-digestible food ingre...

  13. Status of Irish Aquaculture 2005

    Institute, Marine; Mhara, Bord Iascaigh; Teo, Taighde Mara

    2006-01-01

    This is the third annual report on the status of Irish aquaculture (see Parsons et al., 2003, Parsons et al., 2004). As with the previous reports 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 Taighde Mara Teo (TMT). The objectives of this report are: (1) To provide a useful, objective and comprehensive source of informatio...

  14. Comparing Denitrification Rates and Carbon Sources in Commercial Scale Upflow Denitrification Biological Filters in Aquaculture

    Aerobic biological filtration systems employing nitrifying bacteria to remediate excess ammonia and nitrite concentrations are common components of recirculating aquaculture systems (RAS). However, significant water exchange may still be necessary to reduce nitrate concentrations to acceptable leve...

  15. Potential drivers of virulence evolution in aquaculture.

    Kennedy, David A; Kurath, Gael; Brito, Ilana L; Purcell, Maureen K; Read, Andrew F; Winton, James R; Wargo, Andrew R

    2016-02-01

    Infectious diseases are economically detrimental to aquaculture, and with continued expansion and intensification of aquaculture, the importance of managing infectious diseases will likely increase in the future. Here, we use evolution of virulence theory, along with examples, to identify aquaculture practices that might lead to the evolution of increased pathogen virulence. We identify eight practices common in aquaculture that theory predicts may favor evolution toward higher pathogen virulence. Four are related to intensive aquaculture operations, and four others are related specifically to infectious disease control. Our intention is to make aquaculture managers aware of these risks, such that with increased vigilance, they might be able to detect and prevent the emergence and spread of increasingly troublesome pathogen strains in the future. PMID:26834829

  16. EDITORIAL: Strongly correlated electron systems Strongly correlated electron systems

    Ronning, Filip; Batista, Cristian

    2011-03-01

    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 and Andrew P Mackenzie Thermodynamics of itinerant metamagnetic transitions A M Berridge Magnon-mediated pairing and isotope effect in iron-based superconductors Jiansheng Wu and Philip Phillips Nernst quantum oscillations in bulk semi-metals Zengwei Zhu, Huan Yang, Aritra Banerjee, Liam Malone, Benoît Fauqué and Kamran Behnia Signatures of a quantum Griffiths phase in a d-metal alloy close to its ferromagnetic quantum critical point Almut Schroeder, Sara Ubaid-Kassis and Thomas Vojta Influence of super-ohmic dissipation on a disordered quantum critical point Thomas Vojta, José A Hoyos, Priyanka Mohan and Rajesh Narayanan The van Hemmen-Kondo model for disordered cerium systems S G Magalhaes, F M Zimmer and B Coqblin Chemical pressure, dilution and disorder in the heavy fermion compounds Ce3 - xLaxPd20Si6 (x = 1/3, 2/3) H Winkler, K-A Lorenzer, S Laumann, J Custers, A Prokofiev and S Paschen Magnetism of fine particles of Kondo lattices, obtained by high-energy ball-milling E V Sampathkumaran, K Mukherjee, Kartik K Iyer, Niharika Mohapatra and Sitikantha D Das Heavy fermion scaling: uranium versus cerium and ytterbium compounds J M Lawrence, C H Wang, A D Christianson and E D Bauer Temperature dependence of hybridization gaps in metallic heavy-fermion systems Xiaodong Yang, Peter S Riseborough and Tomasz Durakiewicz Low-energy properties of the Kondo lattice model O Bodensiek, R Žitko, R Peters and T Pruschke Temperature dependence of the zero-bias anomaly in the Anderson-Hubbard model: insights from an ensemble of two-site systems R Wortis and W A Atkinson A charge density wave in the hidden order state of URu2Si2 Jung-Jung Su, Yonatan Dubi, Peter Wölfle and Alexander V Balatsky Field-induced suppression of the heavy-fermion state in YbRh2Si2 Gertrud Zwicknagl Discontinuous Hall coefficient at the quantum critical point in YbRh2Si2 Sven Friedemann, Niels Oeschler, Steffen Wirth, Cornelius Krellner, Christoph Geibel, Frank Steglich, Silke Paschen, Stefan Kirchner and Qimiao Si Roles of critical valence fluctuations in Ce- and Yb-based heavy fermion metals Shinji Watanabe and Kazumasa Miyake Unconventional quantum criticality in the pressure-induced heavy-fermion superconductor CeRhIn5 Tuson Park, V A Sidorov, H Lee, F Ronning, E D Bauer, J L Sarrao and J D Thompson Magnetic structure of the antiferromagnetic Fulde-Ferrell-Larkin-Ovchinnikov state Youichi Yanase and Manfred Sigrist Magnetic transition and spin fluctuations in the unconventional antiferromagnetic compound Yb3Pt4 S Zhao, D E MacLaughlin, O O Bernal, J M Mackie, C Marques, Y Janssen and M C Aronson The non-centrosymmetric heavy fermion ferromagnet Sm2Fe12P7 M Janoschek, R E Baumbach, J J Hamlin, I K Lum and M B Maple Magnetic, thermal, and transport properties of the actinide based noncentrosymmetric compounds Th2Fe12P7 and U2Fe12P7 R E Baumbach, J J Hamlin, M Janoschek, I K Lum and M B Maple Magnetic order in Pu2M3Si5 (M = Co, Ni) E D Bauer, P H Tobash, J N Mitchell, J A Kennison, F Ronning, B L Scott and J D Thompson

  17. Probiotics in aquaculture: importance and future perspectives

    Sahu, Maloy Kumar; Swarnakumar, N. S.; Sivakumar, K.; Thangaradjou, T.; Kannan, L.

    2008-01-01

    Aquaculture is one of the fastest developing growth sectors in the world and Asia presently contributes about 90% to the global production. However, disease outbreaks are constraint to aquaculture production thereby affects both economic development of the country and socio-economic status of the local people in many countries of Asia-Pacifi c region. Disease control in aquaculture industry has been achieved by following different methods using traditional ways, synthetic chemicals and antibi...

  18. PARTICULARITIES OF ACCOUNTING IN ORGANIC AQUACULTURE INDUSTRY

    Aurora Aurelia Diaconu; Oana Daniela Lupoae; Iuliana Oana Mihai; Riana Iren Radu

    2015-01-01

    The purpose of this paper is to present our own vision about some general aspects of aquaculture and oyster farming expanded pearlite and their accounting implication. In our references we took into consideration the role of aquaculture as well as the benefits and drawbacks of it. Through this article we aimed to highlight a series of theoretical aspects regarding the role and importance of developing aquaculture national and international as well as a number of practical aspects about involv...

  19. Application of Machine Learning Techniques in Aquaculture

    Akhlaqur Rahman

    2014-04-01

    Full Text Available 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 applications.

  20. Application of Machine Learning Techniques in Aquaculture

    Akhlaqur Rahman; Sumaira Tasnim

    2014-01-01

    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 applications.

  1. Nutrient discharge from China’s aquaculture industry and associated environmental impacts

    Zhang, Ying; Bleeker, Albert; Liu, Junguo

    2015-04-01

    China’s aquaculture industry accounts for the largest share of the world’s fishery production, and provides a principal source of protein for the nation’s booming population. However, the environmental effects of the nutrient loadings produced by this industry have not been systematically studied or reviewed. Few quantitative estimates exist for nutrient discharge from aquaculture and the resultant nutrient enrichment in waters and sediments. In this paper, we evaluate nutrient discharge from aquacultural systems into aquatic ecosystems and the resulting nutrient enrichment of water and sediments, based on data from 330 cases in 51 peer-reviewed publications. Nitrogen use efficiency ranged from 11.7% to 27.7%, whereas phosphorus use efficiency ranged from 8.7% to 21.2%. In 2010, aquacultural nutrient discharges into Chinese aquatic ecosystems included 1044 Gg total nitrogen (184 Gg N from mariculture; 860 Gg N freshwater culture) and 173 Gg total phosphorus (22 Gg P from mariculture; 151 Gg P from freshwater culture). Water bodies and sediments showed high levels of nutrient enrichment, especially in closed pond systems. However, this does not mean that open aquacultural systems have smaller nutrient losses. Improvement of feed efficiency in cage systems and retention of nutrients in closed systems will therefore be necessary. Strategies to increase nutrient recycling, such as integrated multi-trophic aquaculture, and social measures, such as subsidies, should be increased in the future. We recommend the recycling of nutrients in water and sediments by hybrid agricultural-aquacultural systems and the adoption of nutrient use efficiency as an indicator at farm or regional level for the sustainable development of aquaculture; such indicators; together with water quality indicators, can be used to guide evaluations of technological, policy, and economic approaches to improve the sustainability of Chinese aquaculture.

  2. Electronic Nicotine Delivery Systems Key Facts Infographic

    U.S. Department of Health & Human Services — Explore the Electronic Nicotine Delivery Systems Key Facts Infographic which outlines key facts related to electronic nicotine delivery systems (ENDS), including...

  3. Electronic Nicotine Delivery Systems Key Facts Infographic

    U.S. Department of Health & Human Services — Explore the Electronic Nicotine Delivery Systems Key Facts Infographic which outlines key facts related to electronic nicotine delivery systems (ENDS), including...

  4. Reliability of Power Electronic Converter Systems

    The main aims of power electronic converter systems (PECS) are to control, convert, and condition electrical power flow from one form to another through the use of solid-state electronics. This book outlines current research into the scientific modeling, experimentation, and remedial measures for...... electronic converter systems; anomaly detection and remaining-life prediction for power electronics; reliability of DC-link capacitors in power electronic converters; reliability of power electronics packaging; modeling for life-time prediction of power semiconductor modules; minimization of DC......-link capacitance in power electronic converter systems; wind turbine systems; smart control strategies for improved reliability of power electronics system; lifetime modelling; power module lifetime test and state monitoring; tools for performance and reliability analysis of power electronics systems; fault...

  5. Ocean modelling for aquaculture and fisheries in Irish waters

    Dabrowski, T.; Lyons, K.; Cusack, C.; Casal, G.; Berry, A.; Nolan, G. D.

    2015-06-01

    The Marine Institute, Ireland, runs a suite of operational regional and coastal ocean models. Recent developments include several tailored products that focus on the key needs of the Irish aquaculture sector. In this article, an overview of the products and services derived from the models are presented. A shellfish model that includes growth and physiological interactions of mussels with the ecosystem and is fully embedded in the 3-D numerical modelling framework has been developed at the Marine Institute. This shellfish model has a microbial module designed to predict levels of coliform contamination in mussels. This model can also be used to estimate the carrying capacity of embayments, assess impacts of pollution on aquaculture grounds and help to classify shellfish waters. The physical coastal model of southwest Ireland provides a three day forecast of shelf water movement in the region. This is assimilated into a new harmful algal bloom alert system used to inform end-users of potential toxic shellfish events and high biomass blooms that include fish killing species. Further services include the use of models to identify potential sites for offshore aquaculture, to inform studies of potential cross-contamination in farms from the dispersal of planktonic sea lice larvae and other pathogens that can infect finfish and to provide modelled products that underpin the assessment and advisory services on the sustainable exploitation of the marine fisheries resources. This paper demonstrates that ocean models can provide an invaluable contribution to the sustainable blue growth of aquaculture and fisheries.

  6. Zebrafish as animal model for aquaculture nutrition research

    Ulloa, Pilar E.; Medrano, Juan F.; Feijoo, Carmen G.

    2014-01-01

    The aquaculture industry continues to promote the diversification of ingredients used in aquafeed in order to achieve a more sustainable aquaculture production system. The evaluation of large numbers of diets in aquaculture species is costly and requires time-consuming trials in some species. In contrast, zebrafish (Danio rerio) can solve these drawbacks as an experimental model, and represents an ideal organism to carry out preliminary evaluation of diets. In addition, zebrafish has a sequenced genome allowing the efficient utilization of new technologies, such as RNA-sequencing and genotyping platforms to study the molecular mechanisms that underlie the organism’s response to nutrients. Also, biotechnological tools like transgenic lines with fluorescently labeled neutrophils that allow the evaluation of the immune response in vivo, are readily available in this species. Thus, zebrafish provides an attractive platform for testing many ingredients to select those with the highest potential of success in aquaculture. In this perspective article aspects related to diet evaluation in which zebrafish can make important contributions to nutritional genomics and nutritional immunity are discussed. PMID:25309575

  7. Ocean modelling for aquaculture and fisheries in Irish waters

    Dabrowski, T.; Lyons, K.; Cusack, C.; Casal, G.; Berry, A.; Nolan, G. D.

    2016-01-01

    The Marine Institute, Ireland, runs a suite of operational regional and coastal ocean models. Recent developments include several tailored products that focus on the key needs of the Irish aquaculture sector. In this article, an overview of the products and services derived from the models are presented. The authors give an overview of a shellfish model developed in-house and that was designed to predict the growth, the physiological interactions with the ecosystem, and the level of coliform contamination of the blue mussel. As such, this model is applicable in studies on the carrying capacity of embayments, assessment of the impacts of pollution on aquaculture grounds, and the determination of shellfish water classes. Further services include the assimilation of the model-predicted shelf water movement into a new harmful algal bloom alert system used to inform end users of potential toxic shellfish events and high biomass blooms that include fish-killing species. Models are also used to identify potential sites for offshore aquaculture, to inform studies of potential cross-contamination in farms from the dispersal of planktonic sea lice larvae and other pathogens that can infect finfish, and to provide modelled products that underpin the assessment and advisory services on the sustainable exploitation of the resources of marine fisheries. This paper demonstrates that ocean models can provide an invaluable contribution to the sustainable blue growth of aquaculture and fisheries.

  8. Ocean modelling for aquaculture and fisheries in Irish waters

    T. Dabrowski

    2015-06-01

    Full Text Available The Marine Institute, Ireland, runs a suite of operational regional and coastal ocean models. Recent developments include several tailored products that focus on the key needs of the Irish aquaculture sector. In this article, an overview of the products and services derived from the models are presented. A shellfish model that includes growth and physiological interactions of mussels with the ecosystem and is fully embedded in the 3-D numerical modelling framework has been developed at the Marine Institute. This shellfish model has a microbial module designed to predict levels of coliform contamination in mussels. This model can also be used to estimate the carrying capacity of embayments, assess impacts of pollution on aquaculture grounds and help to classify shellfish waters. The physical coastal model of southwest Ireland provides a three day forecast of shelf water movement in the region. This is assimilated into a new harmful algal bloom alert system used to inform end-users of potential toxic shellfish events and high biomass blooms that include fish killing species. Further services include the use of models to identify potential sites for offshore aquaculture, to inform studies of potential cross-contamination in farms from the dispersal of planktonic sea lice larvae and other pathogens that can infect finfish and to provide modelled products that underpin the assessment and advisory services on the sustainable exploitation of the marine fisheries resources. This paper demonstrates that ocean models can provide an invaluable contribution to the sustainable blue growth of aquaculture and fisheries.

  9. Status of Irish Aquaculture 2007

    Institute, Marine; Mhara, Bord Iascaigh; Gaeltachta, Údarás na

    2008-01-01

    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 prov...

  10. Status of Irish Aquaculture 2003

    Institute, Marine; Mhara, Bord Iascaigh; Teo, Taighde Mara

    2004-01-01

    This is the first joint report on the status of Irish aquaculture, which has been produced in collaboration by the three main State agencies that provide support services in the areas of research and development to the industry – Bord Iascaigh Mhara, the Marine Institute and Taighde Mara. The value of industry output was over €1 billion in the period from 1990 to 2003 and this represents a significant socio economic impact in the coastal areas of the south and west coast. The aims of the repo...

  11. Modeling of power electronic systems with EMTP

    Tam, Kwa-Sur; Dravid, Narayan V.

    1989-01-01

    In view of the potential impact of power electronics on power systems, there is need for a computer modeling/analysis tool to perform simulation studies on power systems with power electronic components as well as to educate engineering students about such systems. The modeling of the major power electronic components of the NASA Space Station Freedom Electric Power System is described along with ElectroMagnetic Transients Program (EMTP) and it is demonstrated that EMTP can serve as a very useful tool for teaching, design, analysis, and research in the area of power systems with power electronic components. EMTP modeling of power electronic circuits is described and simulation results are presented.

  12. Directly measured denitrification reveals oyster aquaculture and restored oyster reefs remove nitrogen at comparable high rates

    Coastal systems are increasingly impacted by over-enrichment of nutrients, which has cascading effects for ecosystem functioning. Oyster restoration and aquaculture are both hypothesized to mitigate excessive nitrogen (N) loads via benthic denitrification (DNF). However, this has...

  13. The role of oyster restoration and aquaculture in nitrogen removal within a Rhode Island estuary

    Coastal systems are increasingly impacted by over-enrichment of nutrients, which has cascading effects for ecosystem functioning. Oyster aquaculture and restoration are hypothesized to mitigate excessive nitrogen (N) loads via assimilation, burial, or benthic denitrification. Stu...

  14. Towards functional equivalency: oyster reef restoration and oyster aquaculture remove nitrogen at comparable rates

    Coastal systems are increasingly impacted by over-enrichment of nutrients, which has cascading effects for ecosystem functioning. Oyster restoration and aquaculture are both hypothesized to mitigate excessive nitrogen (N) loads via benthic denitrification (DNF). However, this has...

  15. Feed Additives for Aquaculture and Aquarium Culture

    Barata, Eduardo N; Velez, Zélia

    2011-01-01

    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.

  16. Consumer behaviour and preferences for aquaculture products

    Brunsø, Karen; Scholderer, Joachim; Verbeke, Wim; Olsen, Svein Ottar

    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...

  17. Inland fisheries and aquaculture mission Myanmar

    2009-01-01

    Results of an inland fisheries and aquaculture mission in Myanmar carried out by the Department of Fisheries of Myanmar together with STREAM and NACA to evaluate and plan in the field of inland fisheries from the point of view of livelihoods from freshwater fisheries and aquaculture. (Pdf contains 22 pages)

  18. Environmental Best Management Practices for Aquaculture

    The book “Environmental Best Management Practices for Aquaculture” provides technical guidance to improve the environmental performance of fish and shellfish farming. The book is the only comprehensive guide to mitigation of environmental impacts of aquaculture. Topics include the histiory and use...

  19. Digital simulation of power electronic systems

    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.)

  20. Stringency of environmental regulation and aquaculture growth

    Gedefaw Abate, Tenaw; Nielsen, Rasmus; Tveterås, Ragnar

    2016-01-01

    During the last three decades, aquaculture has been the fastest growing animal-food-producing sector in the world, accounting for half of the present seafood supply. However, there is a significant growth disparity among aquaculture-producing countries. The reasons why some countries have achieved...... remarkable growth in aquaculture while others have stagnated or even declined have not been determined. In this article, we investigate whether environmental regulations have an impact on aquaculture growth. Using a cross-country regression analysis, we show that stringent environmental regulations are...... negatively related to aquaculture growth, whereas GDP growth has a positive effect. Countries often face a difficult balancing act between growth and environmental considerations when devising regulations. Our empirical results suggest that stricter environmental regulations in developed countries have...

  1. Micro-Electronic Nose System

    Zee, Frank C.

    2011-12-01

    The ability to "smell" various gas vapors and complex odors is important for many applications such as environmental monitoring for detecting toxic gases as well as quality control in the processing of food, cosmetics, and other chemical products for commercial industries. Mimicking the architecture of the biological nose, a miniature electronic nose system was designed and developed consisting of an array of sensor devices, signal-processing circuits, and software pattern-recognition algorithms. The array of sensors used polymer/carbon-black composite thin-films, which would swell or expand reversibly and reproducibly and cause a resistance change upon exposure to a wide variety of gases. Two types of sensor devices were fabricated using silicon micromachining techniques to form "wells" that confined the polymer/carbon-black to a small and specific area. The first type of sensor device formed the "well" by etching into the silicon substrate using bulk micromachining. The second type built a high-aspect-ratio "well" on the surface of a silicon wafer using SU-8 photoresist. Two sizes of "wells" were fabricated: 500 x 600 mum² and 250 x 250 mum². Custom signal-processing circuits were implemented on a printed circuit board and as an application-specific integrated-circuit (ASIC) chip. The circuits were not only able to measure and amplify the small resistance changes, which corresponded to small ppm (parts-per-million) changes in gas concentrations, but were also adaptable to accommodate the various characteristics of the different thin-films. Since the thin-films were not specific to any one particular gas vapor, an array of sensors each containing a different thin-film was used to produce a distributed response pattern when exposed to a gas vapor. Pattern recognition, including a clustering algorithm and two artificial neural network algorithms, was used to classify the response pattern and identify the gas vapor or odor. Two gas experiments were performed, one at low gas concentrations between 100 and 600 ppm for two gas vapors and the other at high gas concentrations between 2000 ppm and the saturated vapor pressure of three gas vapors. The array of sensors and circuits were able to uniquely detect and measure these gas vapors and showed a linear response to their concentration levels for both experiments. The results also demonstrated that a reduction in the sensor area by two orders of magnitude (from 4.32 mm² to 0.0625 mm²) did not affect the sensor response. By applying pattern-recognition algorithms, the electronic nose system was able to correctly identify the different gas vapors from the pattern responses of the sensor array.

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

    Ariel E. Turcios

    2014-02-01

    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.

  3. X2000 power system electronics development

    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

    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.

  4. A simple electron-beam lithography system

    Mølhave, Kristian; Madsen, Dorte Nørgaard; Bøggild, Peter

    2005-01-01

    A large number of applications of electron-beam lithography (EBL) systems in nanotechnology have been demonstrated in recent years. In this paper we present a simple and general-purpose EBL system constructed by insertion of an electrostatic deflector plate system at the electron-beam exit of the...

  5. REVIEW OF AQUACULTURE GENETIC RESEARCHES IN THAILAND

    UTHAIRAT NA-NAKORN

    1992-01-01

    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.

  6. Screening for biological activities with application in aquaculture in halophytes from the Algarve coastline

    Palmeira, João Pedro

    2013-01-01

    Infectious diseases often hamper the production of aquatic organisms in aquaculture systems, causing economical losses, environmental problems and consumer safety issues. The conventional way aquaculture producers had to control pathogens was by means of synthetic antibiotics and chemicals. This procedure had consequences in the emergence of more resilient pathogens, drug contamination of seafood products and local ecosystems. To avoid the repercussions of antibiotic use, vacci...

  7. Characterization of antibiotic resistance in commensal bacteria from an aquaculture ecosystem

    Huang, Ying; Zhang, Lu; Tiu, Laura; Wang, Hua H.

    2015-01-01

    The objective of the study was to improve the understanding of antibiotic resistance (AR) ecology through characterization of antibiotic-resistant commensal isolates associated with an aquaculture production system. A total of 4767 isolates non-susceptible to sulfamethoxazole/trimethoprim (Sul/Tri), tetracycline (Tet), erythromycin (Erm), or cefotaxime (Ctx), originated from fish, feed, and environmental samples of an aquaculture farm with no known history of antibiotic applications were exam...

  8. Electrons in 5f Systems

    Le, Duc-Anh

    2010-01-01

    The localized/delocalized duality of 5f electrons plays an important role in understanding the complex physics of actinides. Band-structure calculations based on the ad hoc assumption that 5f electrons are simultaneously localized and delocalized explained the observed dHvA experiments very well. This ad hoc assumption also gives the correct equilibrium volume for delta-Pu. Experimentally, the duality of 5f electrons is observed by inelastic neutron scattering experiments, or by soft X-ray a...

  9. Biogeochemical ecology of aquaculture ponds

    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 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

  10. Electronic Official Personnel Folder System

    US Agency for International Development — The eOPF is a digital recreation of paper personnel folder that stores electronic personnel data spanning an individual's Federal career. eOPF allows employees to...

  11. Understanding electronic systems in semiconductor quantum dots

    Ciftja, Orion

    2013-11-01

    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.

  12. Electronic document management in office systems

    Rabitti, Fausto

    1985-01-01

    This paper summarizes the main aspects concerning the management of electronic documents, that is, documents as they are represented inside the automated office. An electronic document is a multimedia data object which is an aggregation of text, images, attribute, and audio components. A system for the management of electronic documents will be constituted by a number of electronic document servers operating in a network environment together with the user workstations, which are the source of...

  13. Scenarios for Resilient Shrimp Aquaculture in Tropical Coastal Areas

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

    2010-01-01

    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...

  14. Simulations of the ILC Electron Gun and Electron Bunching System

    The International Linear Collider (ILC) is a proposed electron-positron collider, expected to provide insight into important questions in particle physics. A part of the global R and D effort for the ILC is the design of its electron gun and electron bunching system. The present design of the bunching system has two sub-harmonic bunchers, one operating at 108 MHz and one at 433MHz, and two 5-cell 1.3 GHz (L-band) bunchers. This bunching system has previously been simulated using the Phase and Radial Motion in Electron Linear Accelerators (PARMELA) software, and those simulations indicated that the design provides sufficient bunching and acceleration. Due to the complicated dynamics governing the electrons in the bunching system we decided to verify and expand the PARMELA results using the more recent and independent simulation software General Particle Tracer (GPT). GPT tracks the motion and interactions of a set of macro particles, each of which represent a number of electrons, and provides a variety of analysis capabilities. To provide initial conditions for the macro particles, a method was developed for deriving the initial conditions from detailed simulations of particle trajectories in the electron gun. These simulations were performed using the Egun software. For realistic simulation of the L-band bunching cavities, their electric and magnetic fields were calculated using the Superfish software and imported into GPT. The GPT simulations arrived at similar results to the PARMELA simulations for sub-harmonic bunching. However, using GPT it was impossible to achieve an efficient bunching performance of the first L-band bunching cavity. To correct this, the first L-band buncher cell was decoupled from the remaining 4 cells and driven as an independent cavity. Using this modification we attained results similar to the PARMELA simulations. Although the modified bunching system design performed as required, the modifications are technically challenging to implement. Further work is needed to optimize the L-Band buncher design

  15. Reproduction of European Eel in Aquaculture (REEL)

    Tomkiewicz, Jonna; Tybjerg, Lars; Støttrup, Josianne; McEvoy, Fintan; Ravn, Peter; Sørensen, Sune Riis; Lauesen, Peter; Graver, Christian; Munk, Peter; Holst, Lars K.; Vestbö, Bjarne; Svalastoga, Eiliv; Jacobsen, Charlotte; Holst, Bjørn; Steenfeldt, Svend Jørgen; Buelund, Lene; Hornum, Thomas; Kofoed, Tanja

    Project aim: Enhance methods and technology applied to produce and culture European eel larvae as basis for the development of a future self-sustained eel aquaculture. Background: The severe decline of the European eel stock calls for conservation measures including national eel management plans...... and establishment of a self-sustained eel aquaculture. In 2005, the National Institute of Aquatic Resources at the Technical University of Denmark (DTU Aqua), the Faculty of Life Sciences at Copenhagen University (KU-Life) and the eel aquaculture industry started to build up a research and technology...... platform for the development of methods to reproduce European eel in aquaculture. Two major projects: Artificial Reproduction of Eels II and III (ROE II and III) succeeded during 2005-2008 to produce viable eggs and larvae that lived up to 12 days. The larvae thereby accomplished the yolk-sac stage and...

  16. Nonlinear identification of power electronic systems

    Chau, KT; Chan, CC

    1995-01-01

    This paper presents a new approach to modelling power electronic systems using nonlinear system identification. By employing the nonlinear autoregressive moving average with exogenous input (NARMAX) technique, the parametric model of power electronic systems can be derived from the time-domain data. This approach possesses some advantages over available circuit-oriented modelling approaches, such as no small-signal approximation, no circuit idealization and no detailed knowledge of system ope...

  17. Marketing and Aquaculture Sector in Antalya Province

    Gümüş*(2), Erkan; YILMAZ, Serpil

    2011-01-01

    In Turkey, the aquaculture sector that is rapid progress has also become an important sector for Antalya province as in other provinces in recent years. Antalya Province have an important potential both marine and inland water for aquaculture. However, it is not possible to talk about this potential can be used effectively because of an important tourist resort of Antalya Province. Nevertheless, a total of 5482 tons / year capacity has been operating 86 license...

  18. Risks of Using Antifouling Biocides in Aquaculture

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

    2012-01-01

    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...

  19. Recent advances in tropical freshwater aquaculture

    Varghese, T.J.

    1988-01-01

    Several technological advances have been made in tropical freshwater aquaculture during the last three decades. Hatchery production of carp seed was achieved in India and China towards the late 1950's. Channel catfish farming in the U.S. has grown phenomenally. Development of the technology of high density culture using artificial aeration and nutritionally balanced diets has revolutionized freshwater aquaculture, particularly in Israel. Culture of fishes in cages, pens and running water have...

  20. Sustainability aspects of applying GMOs in aquaculture

    Haro, Monica Natalia

    2012-01-01

    Genetic modification technology has been suggested as a way to address challenges in aquaculture and other industries. For instance, the demand for fishmeal and fish oil in aquaculture industry is expected to increase rapidly, potentially resulting in increased prices. Salmon feed represents the majority expense (approximately 60-70%) of the total production costs. Genetically modified plants may be one option to replace the use of marine feed ingredients and at the same time reduce the expen...

  1. High perveance electron gun for the electron cooling system

    The cooling time in the electron cooling system is inversely proportional to the beam current. To obtain high current of the electron beam the control electrode of the gun is provided with a positive potential and an electrostatic trap for secondary electrons appears inside the electron gun. This leads to a decrease in the gun perveance. To avoid this problem, the adiabatic high perveance electron gun with the clearing control electrode is designed in JINR (J. Bosser, Y. Korotaev, I. Meshkov, E. Syresin et al., Nucl. Instr. and Meth. A 391 (1996) 103. Yu. Korotaev, I. Meshkov, A. Sidorin, A. Smirnov, E. Syresin, The generation of electron beams with perveance of 3-6 μA/V3/2, Proceedings of SCHEF'99). The clearing control electrode has a transverse electric field, which clears secondary electrons. Computer simulations of the potential map were made with RELAX3D computer code (C.J. Kost, F.W. Jones, RELAX3D User's Guide and References Manual)

  2. High perveance electron gun for the electron cooling system

    Korotaev, Yu V; Petrov, A; Sidorin, A; Smirnov, A; Syresin, E M; Titkova, I

    2000-01-01

    The cooling time in the electron cooling system is inversely proportional to the beam current. To obtain high current of the electron beam the control electrode of the gun is provided with a positive potential and an electrostatic trap for secondary electrons appears inside the electron gun. This leads to a decrease in the gun perveance. To avoid this problem, the adiabatic high perveance electron gun with the clearing control electrode is designed in JINR (J. Bosser, Y. Korotaev, I. Meshkov, E. Syresin et al., Nucl. Instr. and Meth. A 391 (1996) 103. Yu. Korotaev, I. Meshkov, A. Sidorin, A. Smirnov, E. Syresin, The generation of electron beams with perveance of 3-6 mu A/V sup 3 sup / sup 2 , Proceedings of SCHEF'99). The clearing control electrode has a transverse electric field, which clears secondary electrons. Computer simulations of the potential map were made with RELAX3D computer code (C.J. Kost, F.W. Jones, RELAX3D User's Guide and References Manual).

  3. Corrosion Reliability of Electronic Systems

    Ambat, Rajan; Jensen, Stine G.; Møller, Per

    2008-01-01

    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 pa...

  4. Green and technical efficient growth in Danish fresh water aquaculture

    Nielsen, Rasmus

    2011-01-01

    growth can be achieved by introducing new environmentally friendly water purification systems in Danish fresh water aquaculture. Data Envelopment Analysis is used to investigate whether different water purification systems and farm size influence technical efficiency. The empirical results indicate that...... different water purification systems have no significant influence, although it increases with farm size. The policy implications are that green growth is possible by implementing the new water purification systems, but farmers have no incentive to adopt the new systems under the present regulation. If...

  5. Power Electronics in Wind Turbine Systems

    Blaabjerg, Frede; Chen, Zhe; Teodorescu, Remus; Iov, Florin

    2006-01-01

    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....

  6. Corrosion Reliability of Electronic Systems

    Ambat, Rajan; Jensen, Stine G.; Møller, Per

    2008-01-01

    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...

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

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

    2007-10-01

    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

  8. Rectification in one--dimensional electronic systems

    Braunecker, Bernd; Feldman, D. E.; Marston, J. B.

    2005-01-01

    Asymmetric current--voltage ($I(V)$) curves, known as the diode or rectification effect, in one--dimensional electronic conductors can have their origin from scattering off a single asymmetric impurity in the system. We investigate this effect in the framework of the Tomonaga--Luttinger model for electrons with spin. We show that electron interactions strongly enhance the diode effect and lead to a pronounced current rectification even if the impurity potential is weak. For strongly interacti...

  9. HIRFL-CSR electron cooling system

    Electron cooling technique will be applied to the proposed Lanzhou heavy ion cooler-storage ring (HIRFL-CSR). A electron cooling device with a maximum electron energy of 165 keV and maximum current density of 0.244 A/cm2 is planned to cool heavy ions up to energies of 300 MeV/u. The preliminary design for the cooling system is presented

  10. Electronic Student Attendance Recording System

    Dr. AkramAbedelKarim Ahmad AbdelQader

    2013-03-01

    Full Text Available Bluetooth technology is offering a very robust way to transfer data in faster rates within a short range wireless communication local network. Wireless and radio communication technologies are giving organizations and users many benefits such as portability and flexibility, increased productivity, and lower the installation costs.  Register the attendance and absence for students in the classroom of all educational institutions is one of the most intensive daily operations. In this paper, we are interesting to use the free wireless communication via Bluetooth technology that is available in most mobile phones and computer systems to build a computerized wireless clients-server network system. The client side will be a mobile phone that used to fill the list of attendance and absence for students in a classroom of educational institutions in an easy and fast way.  Server side will contain the centralized database and monitoring attendance system for the distributing clients connected to the system. The idea of this system is developed and implemented on real educational institution. The recorded results show that the system saves a costs and efforts and helps the educational institution to get a more effective system than the old one.

  11. Electronic Student Attendance Recording System

    Dr. AkramAbedelKarim Ahmad AbdelQader

    2013-03-01

    Full Text Available Bluetooth technology is offering a very robust way to transfer data in faster rates within a short range wireless communication local network. Wireless and radio communication technologies are giving organizations and users many benefits such as portability and flexibility, increased productivity, and lower the installation costs.  Register the attendance and absence for students in the classroom of all educational institutions is one of the most intensive daily operations. In this paper, we are interesting to use the free wireless communication via Bluetooth technology that is available in most mobile phones and computer systems to build a computerized wireless clients-server network system. The client side will be a mobile phone that used to fill the list of attendance and absence for students in a classroom of educational institutions in an easy and fast way.  Server side will contain the centralized database and monitoring attendance system for the distributing clients connected to the system. The idea of this system is developed and implemented on real educational institution. The recorded results show that the system saves a costs and efforts and helps the educational institution to get a more effective system than the old one.

  12. Electronic Student Attendance Recording System

    Dr. AkramAbedelKarim Ahmad AbdelQader

    2013-02-01

    Full Text Available Bluetooth technology is offering a very robust way to transfer data in faster rates within a short range wireless communication local network. Wireless and radio communication technologies are giving organizations and users many benefits such as portability and flexibility, increased productivity, and lower the installation costs.  Register the attendance and absence for students in the classroom of all educational institutions is one of the most intensive daily operations. In this paper, we are interesting to use the free wireless communication via Bluetooth technology that is available in most mobile phones and computer systems to build a computerized wireless clients-server network system. The client side will be a mobile phone that used to fill the list of attendance and absence for students in a classroom of educational institutions in an easy and fast way.  Server side will contain the centralized database and monitoring attendance system for the distributing clients connected to the system. The idea of this system is developed and implemented on real educational institution. The recorded results show that the system saves a costs and efforts and helps the educational institution to get a more effective system than the old one.

  13. Electronic states in systems of reduced dimensionality

    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)

  14. Electronic Medical Records Management Systems: An Overview

    Lim Chee Siang Edmund,; Chennupati K. Ramaiah,; Surya Prakash Gulla

    2009-01-01

    Records document the actions of an organisation’s business activities. Nowadays, more and more government agencies, companies and healthcare organisations are moving towards electronic records from records on paper. In healthcare organisations, Electronic Medical Record (EMR) system is being used to capture, organize, maintain and retrieve patient’s medical records. EMR system consists of a comprehensive database used to store and access patient’s healthcare information. The EMR has replaced ...

  15. Facilitating electron transfer in bioelectrocatalytic systems

    Sekretaryova, Alina

    2016-01-01

    Bioelectrocatalytic systems are based on biological entities, such as enzymes, whole cells, parts of cells or tissues, which catalyse electrochemical processes that involve the interaction between chemical change and electrical energy. In all cases, biocatalysis is implemented by enzymes, isolated or residing inside cells or part of cells. Electron transfer (ET) phenomena, within the protein molecules and between biological redox systems and electronics, enable the development of various bioe...

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

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

    2013-01-01

    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...

  17. Magnetic system of the Tevatron electron lens

    The Tevatron Electron Lens (TEL) system consisting of seven SC and four conventional magnets has been developed and fabricated in IHEP for increase of luminosity in Tevatron. The SC cable tension and preload of SC coils are calculated. The chosen cable design and cooling of the SC magnets ensure sufficient temperature margin for operating of SC magnets and their safety during quench. The system of conventional and SC solenoids create necessary trajectory of magnetic field lines for the TEL electron beam motion. SC dipoles and warm correctors permit to carry out correction of the electron beam motion

  18. Electron beam size measurements in the Fermilab Electron Cooling System

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

    2005-09-01

    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.

  19. Data base systems in electronic design engineering

    Williams, D.

    1980-01-01

    The concepts of an integrated design data base system (DBMS) as it might apply to an electronic design company are discussed. Data elements of documentation, project specifications, project tracking, firmware, software, electronic and mechanical design can be integrated and managed through a single DBMS. Combining the attributes of a DBMS data handler with specialized systems and functional data can provide users with maximum flexibility, reduced redundancy, and increased overall systems performance. Although some system overhead is lost due to redundancy in transitory data, it is believed the combination of the two data types is advisable rather than trying to do all data handling through a single DBMS.

  20. Depletion of florfenicol amine in tilapia (Oreochromis sp.) maintained in a recirculating aquaculture system following Aquaflor(R)-medicated feed therapy (20 mg/kg BW/d for 10 days)

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

    2013-01-01

    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.

  1. Security in Electronic Payment Systems

    Roxana Turcu

    2014-12-01

    Full Text Available The payment security becomes fundamental in our days. Based on this statement I have decided to deepen this subject and to study the online payment systems and the connection between them. I have observed that this area becomes the hackers’ attraction and I have realized how important the security of the ecommerce is. Also I have done a research of the possible attacks and I have searched for the countermeasures of this attacks. The result of my research is my payment gateway solution presented in the following lines.

  2. An Internet Based Anonymous Electronic Cash System

    Israt Jahan

    2015-04-01

    Full Text Available There is an increase activity in research to improve the current electronic payment system which is parallel with the progress of internet. Electronic cash system is a cryptographic payment system which offers anonymity during withdrawal and purchase. Electronic cash displays serial numbers which can be recorded to allow further tracing. Contrary to their physical counterparts, e-cash have an inherent limitation; they are easy to copy and reuse (double-spending. An observer is a tamper-resistant device, issued by the Internet bank, which is incorporated with the Internet user’s computer that prevents double-spending physically, i.e., the user has no access to her e-cash and therefore he cannot copy them. In this paper, we shall present an anonymous electronic cash scheme on the internet which incorporates tamper-resistant device with user-module.

  3. Design for Reliability of Power Electronic Systems

    Wang, Huai; Ma, Ke; Blaabjerg, Frede

    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.......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...... 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...

  4. THE DEVELOPMENT OF THE ORGANIC AQUACULTURE. CASE STUDY: ROMANIA

    Silvius STANCIU

    2015-12-01

    Full Text Available Aquaculture contribute ever more to the production of aquatic food worldwide, even if the sustainable limits for majority of wild fish stocks, are now almost reached or even exceeded. In the EU, aquaculture is an important economic activity in many coastal and continental regions. Aquaculture plays an important role in terms of access to food resources and it is necessary to use its potential to contribute to sustainable development, food security, economic growth and employment. In this regard, starting from EU aquaculture objectives, the paper intend to make an analysis of the national situation of aquaculture and its current potential. The paper presented the progress of Romanian investments in aquaculture, identifying needs and opportunities for the Romanian aquaculture development. Taking into consideration the natural resources available and the growth of global request of organic product, the development of ecologic aquaculture might represent o niche market for local producers.

  5. Research Progress in Biological Package for Aquaculture Wastewater Treatment

    Mu, Xi-Dong; Yin-chang Hu; Guang-jun Wang; Jun Chen; Jian-ren Luo

    2010-01-01

    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.

  6. Simple aquaculture training for rural development in Zimbabwe

    Kibria, G.

    1991-01-01

    A summary is provided of a course introduced in 1987 at the Chaminuka Training Centre in Zimbabwe for training in rural aquaculture. The recruitment of trainees, aquaculture and rural development, the curriculum and practical training are outlined.

  7. Vertical Integration in the Taiwan Aquaculture Industry

    Tzong-Ru Lee (Jiun-Shen

    2011-12-01

    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.

  8. Streptomyces Bacteria as Potential Probiotics in Aquaculture

    Tan, Loh Teng-Hern; Chan, Kok-Gan; Lee, Learn-Han; Goh, Bey-Hing

    2016-01-01

    In response to the increased seafood demand from the ever-going human population, aquaculture has become the fastest growing animal food-producing sector. However, the indiscriminate use of antibiotics as a biological control agents for fish pathogens has led to the emergence of antibiotic resistance bacteria. Probiotics are defined as living microbial supplement that exert beneficial effects on hosts as well as improvement of environmental parameters. Probiotics have been proven to be effective in improving the growth, survival and health status of the aquatic livestock. This review aims to highlight the genus Streptomyces can be a good candidate for probiotics in aquaculture. Studies showed that the feed supplemented with Streptomyces could protect fish and shrimp from pathogens as well as increase the growth of the aquatic organisms. Furthermore, the limitations of Streptomyces as probiotics in aquaculture is also highlighted and solutions are discussed to these limitations. PMID:26903962

  9. Involvement of rural women in aquaculture: an innovative approach

    Shaleesha, A.; Stanley, V.A.

    2000-01-01

    Although women have proved to be competent in adopting new aquaculture technologies, their role is very much restricted and often ignored. One of the major reasons is the location of aquaculture sites and several sociocultural taboos against women who strive to earn for their familyÆs subsistence in rural areas. There is a gender bias in many aquaculture activities. To ensure that women utilize their full potential in profitable activities like aquaculture, it is necessary to provide capacity...

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

    Dutta, Mitra

    1998-01-01

    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.

  11. Quantifying electron transfer reactions in biological systems

    Sjulstok, Emil Sjulstok; Olsen, Jógvan Magnus Haugaard; Solov'yov, Ilia A

    2015-01-01

    which for example occur in photosynthesis, cellular respiration, DNA repair, and possibly magnetic field sensing. Quantum biology uses computation to model biological interactions in light of quantum mechanical effects and has primarily developed over the past decade as a result of convergence between...... quantum physics and biology. In this paper we consider electron transfer in biological processes, from a theoretical view-point; namely in terms of quantum mechanical and semi-classical models. We systematically characterize the interactions between the moving electron and its biological environment to...... deduce the driving force for the electron transfer reaction and to establish those interactions that play the major role in propelling the electron. The suggested approach is seen as a general recipe to treat electron transfer events in biological systems computationally, and we utilize it to describe...

  12. General-Purpose Electronic System Tests Aircraft

    Glover, Richard D.

    1989-01-01

    Versatile digital equipment supports research, development, and maintenance. Extended aircraft interrogation and display system is general-purpose assembly of digital electronic equipment on ground for testing of digital electronic systems on advanced aircraft. Many advanced features, including multiple 16-bit microprocessors, pipeline data-flow architecture, advanced operating system, and resident software-development tools. Basic collection of software includes program for handling many types of data and for displays in various formats. User easily extends basic software library. Hardware and software interfaces to subsystems provided by user designed for flexibility in configuration to meet user's requirements.

  13. Electronic control systems for commercial refrigerating units

    Giegold, D.

    1987-08-01

    A practical example facilitates access to the changes and consequences of the conversion of conventional electromechanically controlled refrigerating systems into electronic ones (measured-value sensors, time programs, CMOS functions, cooling circuits). Details are given on cold storage control systems. A summary informs about the considerable advantages of electronic control systems, i.e. their improved reliability and operational safety (absence of mechanical components), very accurate timing functions, self-diagnoses, easy-to-maintain/easy-to-service characteristics, and high retrofitting flexibility. (HWJ).

  14. Symmetry of many-electron systems

    Kaplan, I G

    2013-01-01

    Symmetry of Many-Electron Systems discusses the group-theoretical methods applied to physical and chemical problems. Group theory allows an individual to analyze qualitatively the elements of a certain system in scope. The text evaluates the characteristics of the Schrodinger equations. It is proved that some groups of continuous transformation from the Lie groups are useful in identifying conditions and in developing wavefunctions. A section of the book is devoted to the utilization of group-theoretical methods in quantal calculations on many-electron systems. The focus is on the use of group

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

    A. M. Snow; Abdel E. Ghaly

    2008-01-01

    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....

  16. Harry K. Dupree Stuttgart National Aquaculture Research Center

    Aquaculture (fish farming) has played an ever-increasing role in providing people with fish, shrimp, and shellfish. Aquaculture is currently the fastest growing sector of global food production and in 2011 totaled 60 million tons valued at $119 billion. The production of food-fish from aquaculture...

  17. Design and Application of a Solar Mobile Pond Aquaculture Water Quality-Regulation Machine Based in Bream Pond Aquaculture.

    Liu, Xingguo; Xu, Hao; Ma, Zhuojun; Zhang, Yongjun; Tian, Changfeng; Cheng, Guofeng; Zou, Haisheng; Lu, Shimin; Liu, Shijing; Tang, Rong

    2016-01-01

    Bream pond aquaculture plays a very important role in China's aquaculture industry and is the main source of aquatic products. To regulate and control pond water quality and sediment, a movable solar pond aquaculture water quality regulation machine (SMWM) was designed and used. This machine is solar-powered and moves on water, and its primary components are a solar power supply device, a sediment lifting device, a mechanism for walking on the water's surface and a control system. The solar power supply device provides power for the machine, and the water walking mechanism drives the machine's motion on the water. The sediment lifting device orbits the main section of the machine and affects a large area of the pond. Tests of the machine's mechanical properties revealed that the minimum illumination necessary for the SMWM to function is 13,000 Lx and that its stable speed on the water is 0.02-0.03 m/s. For an illumination of 13,000-52,500 Lx, the sediment lifting device runs at 0.13-0.35 m/s, and its water delivery capacity is 110-208 m3/h. The sediment lifting device is able to fold away, and the angle of the suction chamber can be adjusted, making the machine work well in ponds at different water depths from 0.5 m to 2 m. The optimal distance from the sediment lifting device to the bottom of the pond is 10-15 cm. In addition, adjusting the length of the connecting rod and the direction of the traction rope allows the SMWM to work in a pond water area greater than 80%. The analysis of water quality in Wuchang bream (Parabramis pekinensis) and silver carp (Hypophthalmichthys molitrix) culture ponds using the SMWM resulted in decreased NH3+-N and available phosphorus concentrations and increased TP concentrations. The TN content and the amount of available phosphorus in the sediment were reduced. In addition, the fish production showed that the SMWM enhanced the yields of Wuchang bream and silver carp by more than 30% and 24%, respectively. These results indicate that the SMWM may be suitable for Wuchang bream pond aquaculture in China and that it can be used in pond aquaculture for regulating and controlling water quality. PMID:26789004

  18. Design and Application of a Solar Mobile Pond Aquaculture Water Quality-Regulation Machine Based in Bream Pond Aquaculture

    Liu, Xingguo; Xu, Hao; Ma, Zhuojun; Zhang, Yongjun; Tian, Changfeng; Cheng, Guofeng; Zou, Haisheng; Lu, Shimin; Liu, Shijing; Tang, Rong

    2016-01-01

    Bream pond aquaculture plays a very important role in China’s aquaculture industry and is the main source of aquatic products. To regulate and control pond water quality and sediment, a movable solar pond aquaculture water quality regulation machine (SMWM) was designed and used. This machine is solar-powered and moves on water, and its primary components are a solar power supply device, a sediment lifting device, a mechanism for walking on the water’s surface and a control system. The solar power supply device provides power for the machine, and the water walking mechanism drives the machine’s motion on the water. The sediment lifting device orbits the main section of the machine and affects a large area of the pond. Tests of the machine’s mechanical properties revealed that the minimum illumination necessary for the SMWM to function is 13,000 Lx and that its stable speed on the water is 0.02–0.03 m/s. For an illumination of 13,000–52,500 Lx, the sediment lifting device runs at 0.13–0.35 m/s, and its water delivery capacity is 110–208 m3/h. The sediment lifting device is able to fold away, and the angle of the suction chamber can be adjusted, making the machine work well in ponds at different water depths from 0.5 m to 2 m. The optimal distance from the sediment lifting device to the bottom of the pond is 10–15 cm. In addition, adjusting the length of the connecting rod and the direction of the traction rope allows the SMWM to work in a pond water area greater than 80%. The analysis of water quality in Wuchang bream (Parabramis pekinensis) and silver carp (Hypophthalmichthys molitrix) culture ponds using the SMWM resulted in decreased NH3+–N and available phosphorus concentrations and increased TP concentrations. The TN content and the amount of available phosphorus in the sediment were reduced. In addition, the fish production showed that the SMWM enhanced the yields of Wuchang bream and silver carp by more than 30% and 24%, respectively. These results indicate that the SMWM may be suitable for Wuchang bream pond aquaculture in China and that it can be used in pond aquaculture for regulating and controlling water quality. PMID:26789004

  19. Electron-phonon interactions in correlated systems

    There exist attempts to describe the superconducting mechanism operating in HTS as based on antiferromagnetic fluctuations. It is not our intention to dwell on the superconducting mechanism, even though this is very a important issue. The main aim is to discuss the problem of interplay between electron-phonon and electron-electron interactions in correlated systems. We believe such analysis can be of importance for various materials and not only HTS'S. We shall however mainly refer to experiments on this last class of superconductors. Severe complications are to be expected by studying the problem. As is well known electron correlations are very important in narrow band systems, where the relevant electronic scale EF is quite small. In those circumstances, the phonon energy scale ωD is of comparable magnitude, with the ratio ωD/EF of order 1 signalling a possible break down of the Migdal - Eliashberg description of the electron-phonon interaction in metals. Here we shall assume the validity of the Migdal-Eliashberg approximation and concentrate on the mutual influence of electron and phonon subsystems. In the next section we shall discuss experimental motivation for and theoretical work related to the present problem. Section 3 contains a brief discussion of our theory. It is a self-consistent theory a la Migdal with strong correlations treated with an auxiliary boson technique. We conclude with results and their discussion. (orig.)

  20. Bio-integrated electronics and sensor systems

    Yeo, Woon-Hong; Webb, R. Chad; Lee, Woosik; Jung, Sungyoung; Rogers, John A.

    2013-05-01

    Skin-mounted epidermal electronics, a strategy for bio-integrated electronics, provide an avenue to non-invasive monitoring of clinically relevant physiological signals for healthcare applications. Current conventional systems consist of single-point sensors fastened to the skin with adhesives, and sometimes with conducting gels, which limits their use outside of clinical settings due to loss of adhesion and irritation to the user. In order to facilitate extended use of skin-mounted healthcare sensors without disrupting everyday life, we envision electronic monitoring systems that integrate seamlessly with the skin below the notice of the user. This manuscript reviews recent significant results towards our goal of wearable electronic sensor systems for long-term monitoring of physiological signals. Ultra-thin epidermal electronic systems (EES) are demonstrated for extended use on the skin, in a conformal manner, including during everyday bathing and sleeping activities. We describe the assessment of clinically relevant physiological parameters, such as electrocardiograms (ECG), electromyograms (EMG), electroencephalograms (EEG), temperature, mechanical strain and thermal conductivity, using examples of multifunctional EES devices. Additionally, we demonstrate capability for real life application of EES by monitoring the system functionality, which has no discernible change, during cyclic fatigue testing.

  1. VHDL Model of Electronic-Lock System

    Noga, J.; Bartsch, E.; Bell, I.M; D. Miklik; B. R. Bannister; K. Vlcek

    2000-01-01

    The paper describes the design of an electronic-lock system which wascompleted as part of the Basic VHDL course in the Department of Controland Measurement Faculty of Electrical Engineering and Informatics,Technical University of Ostrava, Czech Republic in co-operation withthe Department if Electronic Engineering, University of Hull, GreatBritain in the frame of TEMPUS project no. S_JEP/09468-95.

  2. Electronic nicotine delivery systems: a research agenda

    Etter, Jean-François; Bullen, Chris; Flouris, Andreas D; Laugesen, Murray; Eissenberg, Thomas

    2011-01-01

    Electronic nicotine delivery systems (ENDS, also called electronic cigarettes or e-cigarettes) are marketed to deliver nicotine and sometimes other substances by inhalation. Some tobacco smokers report that they used ENDS as a smoking cessation aid. Whether sold as tobacco products or drug delivery devices, these products need to be regulated, and thus far, across countries and states, there has been a wide range of regulatory responses ranging from no regulation to complete bans. The empiric...

  3. Electronic Toll Collection System (ETC) User Survey

    Yim, Youngbin

    1991-01-01

    This is a summary of several surveys concerning the use of an electronic toll collection system (ETC) among San Francisco Bay Area motorists. The objective of these surveys was to determine the level of interest in subscribing to an electronic toll collection service for Bay Area toll bridges. The issues addressed in the surveys were: (1) interest in the ETC service; (2) preferred types of automated vehicle identification (AVI) tags; (3) preferred location or placement of AVI tags on the vehi...

  4. VHDL Model of Electronic-Lock System

    J. Noga

    2000-04-01

    Full Text Available The paper describes the design of an electronic-lock system which wascompleted as part of the Basic VHDL course in the Department of Controland Measurement Faculty of Electrical Engineering and Informatics,Technical University of Ostrava, Czech Republic in co-operation withthe Department if Electronic Engineering, University of Hull, GreatBritain in the frame of TEMPUS project no. S_JEP/09468-95.

  5. Electron localization in one-dimensional systems

    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)

  6. Threat modeling for electronic health record systems.

    Almulhem, Ahmad

    2012-10-01

    The security of electronic health record (EHR) systems is crucial for their growing acceptance. There is a need for assurance that these records are securely protected from attacks. For a system as complex as an EHR system, the number of possible attacks is potentially very large. In this paper, a threat modeling methodology, known as attack tree, is employed to analyze attacks affecting EHR systems. The analysis is based on a proposed generic client-server model of EHR systems. The developed attack tree is discussed along with some system properties that enable quantitative and qualitative analysis. A list of suggested countermeasures are also highlighted. PMID:21870030

  7. Investigation into the sustainability of organic aquaculture of Atlantic cod (Gadus morhua

    Benjamin Birt

    2009-09-01

    Full Text Available Wild stocks of Atlantic cod (Gadus morhua are low. With fisheries in decline, continued demand for cod has led to a fledgling aquaculture industry and current forecasts call for rapid growth. However, critics blame aquaculture of carnivorous species for further depleting fish stocks and for its wider effects on the marine environment. We examine the activities of Johnson Seafarms, a sea-cage organic cod farming facility in the Shetland Islands, to investigate whether “organic” cod farming can be environmentally, economically, and socially sustainable. Data were collected via public questionnaires and interviews with aquaculture experts. The results show that, before it closed in 2008, Johnson Seafarms was addressing the environmental concerns traditionally associated with aquaculture of carnivorous species and that economic viability is possible as a market exists for organically farmed cod at prices higher than for wild fish. We conclude that organic cod farming, as was practiced in the Shetland Islands, is sustainable on that scale. While the industry has room for measured expansion, overexpansion would increase pressure on natural systems, undermining environmental and, ultimately, social and economic sustainability. Producers and regulators should consider alternative techniques, including land-based or integrated aquaculture systems. Any development should be accompanied by further research regarding the industry’s sustainability.

  8. Power electronics system modeling and simulation

    Lai, Jih-Sheng

    1994-12-31

    This paper introduces control system design based softwares, SIMNON and MATLAB/SIMULINK, for power electronics system simulation. A complete power electronics system typically consists of a rectifier bridge along with its smoothing capacitor, an inverter, and a motor. The system components, featuring discrete or continuous, linear or nonlinear, are modeled in mathematical equations. Inverter control methods,such as pulse-width-modulation and hysteresis current control, are expressed in either computer algorithms or digital circuits. After describing component models and control methods, computer programs are then developed for complete systems simulation. Simulation results are mainly used for studying system performances, such as input and output current harmonics, torque ripples, and speed responses. Key computer programs and simulation results are demonstrated for educational purposes.

  9. A Flexible Electronic Commerce Recommendation System

    Gong, Songjie

    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.

  10. Electron-optical system of ultrahigh-voltage electron microscope

    Stoyanov, P.A.; Makarova, I.S.; Freidman, A.V.

    1988-06-01

    The main features of the electron-optical SVEM-1 complex, which is currently being built and has an accelerating voltage of 2 MV, are described. These include the modular windings of the lenses, the attachments for mechanically centering the lens poles, the deflection systems for adjustment purposes and other operations, an objective with a stigmator and interchangeable pole pieces, and other column lenses. The theoretical resolution of the instrument with attachments is 0.12 to 0.15 nanometer and the ultimate resolution is up to 0.09 nanometers.

  11. Electron processing systems for environmental applications

    Electron Beam processing is widely used in a variety of fields. Examples are: crosslinking of plastics and rubber materials, curing of coatings, and so on. Nissin-High Voltage (NHV) has been supplying many types of EB accelerators for many years for a variety of applications. Recently the demand to use Electron Beam Technology for environmental applications has been increasing. DeSO2 and deNOx treatment plus decontamination of water by Electron Beam appear to be the most promising. Over the past several years, NHV has installed several EB units for deSO2 and deNOx applications. Currently NHV will be supplying two 800KV-300Wx2 heads units to IAEA. This system will be installed in Poland and has been designated ''Demo Plant for deSO2 and deNOx''. This paper describes the requirements for this EB System and also discusses the unique parameters of the system

  12. Collimation system for electron arc therapy

    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)

  13. Electronic system of TBR tokamak device

    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)

  14. Power Electronics for Renewable Energy Systems

    Choi, U. M.; Lee, K. B.; Blaabjerg, Frede

    The use of renewable energy sources are increased because of the depletion of natural resources and the increasing pollution level from energy production. The wind energy and the solar energy are most widely used among the renewable energy sources. Power electronics is needed in almost all kinds of...... renewable energy system. It controls the renewable source and interfaces with the load effectively, which can be grid-connected or van work in stand-alone mode. In this presentation, overview of wind and photovoltaic energy systems are introduced. Next, the power electronic circuits behind the most common...

  15. AQUA-USERS: AQUAculture USEr Driven Operational Remote Sensing Information Services

    Laanen, Marnix; Poser, Kathrin; Peters, Steef; de Reus, Nils; Ghebrehiwot, Semhar; Eleveld, Marieke; Miller, Peter; Groom, Steve; Clements, Oliver; Kurekin, Andrey; Martinez Vicente, Victor; Brotas, Vanda; Sa, Carolina; Couto, Andre; Brito, Ana; Amorim, Ana; Dale, Trine; Sorensen, Kai; Boye Hansen, Lars; Huber, Silvia; Kaas, Hanne; Andersson, Henrik; Icely, John; Fragoso, Bruno

    2015-12-01

    The FP7 project AQUA-USERS provides the aquaculture industry with user-relevant and timely information based on the most up-to-date satellite data and innovative optical in-situ measurements. Its key purpose is to develop an application that brings together satellite information on water quality and temperature with in-situ observations as well as relevant weather prediction and met-ocean data. The application and its underlying database are linked to a decision support system that includes a set of (user-determined) management options. Specific focus is on the development of indicators for aquaculture management including indicators for harmful algae bloom (HAB) events. The methods and services developed within AQUA-USERS are tested by the members of the user board, who represent different geographic areas and aquaculture production systems.

  16. Automatic control variac system for electronic accelerator

    An automatic control variac system is designed in order to satisfy the controlling requirement of the electronic accelerator developed by the Institute. Both design and operational principles, structure of the system as well as the software of industrial PC and micro controller unit are described. The interfaces of the control module are RS232 and RS485. A fiber optical interface (FOC) could be set up if an industrial FOC network is necessary, which will extend the filed of its application and make the communication of the system better. It is shown in practice that the system can adjust the variac output voltage automatically and assure the accurate and automatic control of the electronic accelerator. The system is designed in accordance with the general design principles and possesses the merits such as easy operation and maintenance, good expansibility, and low cost, thus it could also be used in other industrial branches. (authors)

  17. Prognostics for Electronics Components of Avionics Systems

    Celaya, Jose R.; Saha, Bhaskar; Wysocki, Philip F.; Goebel, Kai F.

    2009-01-01

    Electronics components have and increasingly critical role in avionics systems and for the development of future aircraft systems. Prognostics of such components is becoming a very important research filed as a result of the need to provide aircraft systems with system level health management. This paper reports on a prognostics application for electronics components of avionics systems, in particular, its application to the Isolated Gate Bipolar Transistor (IGBT). The remaining useful life prediction for the IGBT is based on the particle filter framework, leveraging data from an accelerated aging tests on IGBTs. The accelerated aging test provided thermal-electrical overstress by applying thermal cycling to the device. In-situ state monitoring, including measurements of the steady-state voltages and currents, electrical transients, and thermal transients are recorded and used as potential precursors of failure.

  18. Copper toxicity in aquaculture: A practical approach

    Copper sulfate has been used in aquaculture for many years to control weeds, algae, snails (which carry catfish trematode), and ecto-parasitic organisms in catfish production. Our research has also shown it to be safe and effective to treat fungus on various fish eggs (catfish, hybrid striped bass,...

  19. Application of physics technology in aquaculture

    Experiments show that after hydrobiology stimulation by a certain dosage of a physical field such as electromagnetic, laser, or neutron irradiation, hydorbiological activity can be improved, and consequently yield and quality enhanced. Recent advances in the application of physical fields in aquaculture are summarized, and prospects for future developments presented

  20. Prevention of infectious diseases in aquaculture

    1989-01-01

    Infectious diseases remain one of the most important limitations to the successful propagation of aquatic animals. Most of the losses caused by pathogens in aquaculture could be prevented by health inspection, adequate environment and sound management practices. Effective control measures, mainly based upon 1) avoidance of pathogens 2) modification of the environment 3) improvement of host resistance 4) vaccination and 5) chemoprophylaxis are described.

  1. Inverness College: Innovations in Aquaculture Training.

    Regional Technology Strategies, Inc., Carrboro, NC.

    This paper describes the aquaculture program developed at Inverness College in Scotland. Inverness is located in the Scottish Highlands and serves an area roughly the size of Belgium, but with a population of only 300,000. The regional infrastructure and human capital resources in the Highlands are relatively weak due to inadequate transportation,…

  2. Constitution of aquacultural stocks: Genetic aspects.

    Chevassus, B.

    1989-01-01

    Before reaching of production level justifying an elaborated genetic improvement program, the new aquaculture species deserve a minimal strategy to avoid the consequences of uncontrolled genetic phenomena. Three main aspects will be discussed: initial constitution of the broodstock; maintenance of the broodstock; selection of the broodstock.

  3. Perception of Alabama Science and Career Technology Teachers Concerning Teaching the Alabama Aquaculture Course of Study

    Cline, David John

    The purpose of this study was to improve teachers' ability to effectively use aquaculture as a tool to teach math and science. The study population included Alabama science and career tech teachers that were certified to teach the Alabama aquaculture course of study. The teachers were electronically surveyed regarding their perceptions of the importance of the aquascience elective and aquaculture science course content standards, their knowledge of those topics and how they perceived the quality of available teaching materials. While all of the content standards were rated above average in importance, aquaculture career awareness and safety concerns were rated the highest by teachers. Teachers were most knowledgeable about career opportunities, categorization of aquaculture species, and the adaptations of aquatic organisms. The average materials ratings were below average for all content standards. The highest rated materials were for career opportunities, categorization of species and safety topics. Using Borich's (1980) model of mean weighted discrepancy scores, the control of diseases and pests in the aquatic environment and concepts associated with health management of aquacrops were identified as top priorities for in-service teacher training. Aquaculture industry infrastructure and the effects of the fishing industry were also identified as priority training topics. Teachers were self-divided into 3 categories those that taught science (SCI), career tech (CTE) and those that taught both (BOTH). They were further divided by their level of experience. A multivariate analysis of variance (MANOVA) revealed a significant effect between teacher types but there was no significant interaction effect between (a) teacher type and experience level or (b) the two levels of experience. A follow-up analysis of variance (ANOVA) indicated that the science teachers thought significantly less of the available materials than either the CTE or BOTH groups.

  4. Exotic Superconductivity in Correlated Electron Systems

    Over the past decades, the search for high-Tc superconductivity (SC) and its novel superconducting mechanisms is one of the most challenging tasks of condensed matter physicists and material scientists, wherein the most striking achievement is the discovery of high-c and unconventional superconductivity in strongly correlated 3d-electron systems, such as cuprates and iron pnictides/chalcogenides. Those exotic superconductors display the behaviors beyond the scope of the BCS theory (in the SC states) and the Landau-Fermi liquid theory (in the normal states). In general, such exotic superconductivity can be seen as correlated electron systems, where there are strong interplays among charge, spin, orbital, and lattice degrees of freedom. Thus, we focus on the exotic superconductivity in materials with correlated electrons in the present special issue

  5. Capturing Ecosystem Services, Stakeholders' Preferences and Trade-Offs in Coastal Aquaculture Decisions: A Bayesian Belief Network Application

    Schmitt, Laetitia Helene Marie; Brugere, Cecile

    2013-01-01

    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...

  6. Electronic Performance Support Systems and Technological Literacy

    Maughan, George R.

    2005-01-01

    Electronic performance support systems (EPSS) can provide alternative learning opportunities to supplement traditional classroom or training strategies. Today's students may benefit from educational settings and strategies that they will use in the future. In using EPSS to nurture the development of technological literacy, workers and students can…

  7. Soft errors in modern electronic systems

    Nicolaidis, Michael

    2010-01-01

    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

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

    RB Lopes

    2011-05-01

    Full Text Available 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 remove 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.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.

  9. The electron-neutrino system, ch. 3

    Relativistic kinetic gas theory is applied to a mixture of electrons and electronic neutrinos. The phenomena of diffusion are especially studied in this system, assuming properties comparable to those of the universe in the lepton era as assumed in the hot big bang theory: a hot (Tapproximately 1012K), dense (n = 1038) mixture, colliding elastically. An expression for the diffusion coefficient is derived and numerical values are computed as a function of the reduced temperature z-1 = kT/mc2, assuming equal number densities

  10. Evaluation on Biofilter in Recirculating Integrated Multi-Trophic Aquaculture

    Asfie Maidie

    2013-06-01

    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

  11. Electron cyclotron resonance ion source control system

    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)

  12. The Small Explorer power system electronics

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

    1991-01-01

    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.

  13. Application of refrigeration system in electronics cooling

    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

  14. Temperature measurement systems in wearable electronics

    Walczak, S.; Go?ebiowski, J.

    2014-08-01

    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.

  15. NASA Electronic Library System (NELS) optimization

    Pribyl, William L.

    1993-01-01

    This is a compilation of NELS (NASA Electronic Library System) Optimization progress/problem, interim, and final reports for all phases. The NELS database was examined, particularly in the memory, disk contention, and CPU, to discover bottlenecks. Methods to increase the speed of NELS code were investigated. The tasks included restructuring the existing code to interact with others more effectively. An error reporting code to help detect and remove bugs in the NELS was added. Report writing tools were recommended to integrate with the ASV3 system. The Oracle database management system and tools were to be installed on a Sun workstation, intended for demonstration purposes.

  16. 42 CFR 456.722 - Electronic claims management system.

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Electronic claims management system. 456.722... Electronic Claims Management System for Outpatient Drug Claims § 456.722 Electronic claims management system... electronic claims management (ECM) system to perform on-line, real-time (that is, immediate)...

  17. Enhancement of existing geothermal resource utilization by cascading to intensive aquaculture

    Zachritz, W.H., II; Polka, R.; Schoenmackers

    1996-04-01

    A demonstration high rate aquaculture production system utilizing a cascaded geothermal resource was designed, constructed and operated to fulfill the objectives of this project. Analysis of the energy and water balances for the system indicated that the addition of an Aquaculture Facility expanded the use of the existing resource. This expanded use in no way affected the up- stream processes. Analysis of the system`s energy and water requirements indicated that the present resource was under-utilized and could be expanded. Energy requirements appeared more limiting than water use, but the existing system could be expanded to a culture volume of 72,000 gal. This system would have a potential production capacity of 93,600 lb/yr with a potential market value of $280,00/yr. Based on the results of this study, the heat remaining in the geothermal fluid from one square foot of operating greenhouse is sufficient to support six gallons of culture water for a high density aquaculture facility. Thus, the over 1.5M ft{sup 2} of existing greenhouse space in New Mexico, has the potential to create an aquaculture industry of nearly 9M gal. This translates to an annual production potential of 11.7M lb with a market value of $35.lM.

  18. Evaluation of three types of structured floating plastic media in moving bed biofilters for total ammonia nitrogen removal in a low salinity hatchery recirculating aquaculture system

    Three different commercially available structural plastic media were evaluated in triplicate in moving bed toriod filters under low salinity (11-12 ppt) warm water culture conditions and two different feed loading rates. The culture system consisted of nine separate modules that include a double dra...

  19. Electron correlations in narrow band systems

    The effect of the electron correlations in narrow bands, such as d(f) bands in the transition (rare earth) metals and their compounds and the impurity bands in doped semiconductors is studied. The narrow band systems is described, by the Hubbard Hamiltonian. By proposing a local self-energy for the interacting electron, it is found that the results are exact in both atomic and band limits and reduce to the Hartree Fock results for U/Δ → 0, where U is the intra-atomic Coulomb interaction and Δ is the bandwidth of the noninteracting electrons. For the Lorentzian form of the density of states of the noninteracting electrons, this approximation turns out to be equivalent to the third Hubbard approximation. A simple argument, based on the mean free path obtained from the imaginary part of the self energy, shows how the electron correlations can give rise to a discontinous metal-nonmetal transition as proposed by Mott. The band narrowing and the existence of the satellite below the Fermi energy in Ni, found in photoemission experiments, can also be understood. (Author)

  20. Electron radiation belts of the solar system

    Mauk, B. H.; Fox, N. J.

    2010-12-01

    To address factors dictating similarities and differences between solar system radiation belts, we present comparisons between relativistic electron radiation belt spectra of all five strongly magnetized planets: Earth, Jupiter, Saturn, Uranus, and Neptune. We choose observed electron spectra with the highest intensities near ˜1 MeV and compare them against expectations based on the so-called Kennel-Petschek limit (KP). For evaluating the KP limit, we begin with a recently published relativistic formulation and then add several refinements of our own. Specifically, we utilized a more flexible analytic spectral shape that allows us to accurately fit observed radiation belt spectra, and we examine the differential characteristics of the KP limit. We demonstrate that the previous finding that KP-limited spectra take on an E-1 shape in the nonrelativistic formulation is also roughly preserved with the relativistic formulation; this shape is observed at several of the planets studied. We also conclude that three factors limit the highest relativistic electron radiation belt intensities within solar system planetary magnetospheres: (1) plasma whistler mode interactions that limit differential spectral intensities to a differential Kennel-Petschek limit (Earth, Jupiter, and Uranus), (2) the absence of robust acceleration processes associated with injection dynamics (Neptune), and (3) material interactions between the radiation electrons and clouds of gas and dust (Saturn).

  1. Power Electronics for Renewable Energy Systems

    Choi, U. M.; Lee, K. B.; Blaabjerg, Frede

    The use of renewable energy sources are increased because of the depletion of natural resources and the increasing pollution level from energy production. The wind energy and the solar energy are most widely used among the renewable energy sources. Power electronics is needed in almost all kinds of...... renewable energy system. It controls the renewable source and interfaces with the load effectively, which can be grid-connected or van work in stand-alone mode. In this presentation, overview of wind and photovoltaic energy systems are introduced. Next, the power electronic circuits behind the most common...... wind and photovoltaic configurations are discussed. Finally, their controls and important requirements for grid connection are explained....

  2. Magnetic properties of strongly disordered electronic systems

    Sachdev, Subir

    1997-01-01

    We present a unified, global perspective on the magnetic properties of strongly disordered electronic systems, with special emphasis on the case where the ground state is metallic. We review the arguments for the instability of the disordered Fermi liquid state towards the formation of local magnetic moments, and argue that their singular low temperature thermodynamics are the ``quantum Griffiths'' precursors of the quantum phase transition to a metallic spin glass; the local moment formation...

  3. Advanced Photonic and Electronic Systems WILGA 2010

    Romaniuk, R S

    2010-01-01

    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 professi...

  4. Symmetry of many-electron systems

    Two major sections are presented. In the first, mathematical apparatus, topics covered are: basic concepts and theorems of group theory, the permutation group, groups of linear transformations, and tensor representations and tensor operators. The second section covers symmetry and quantal calculations and includes: principles of the application of group theory to quantum mechanics, classification of states, the method of coefficients of fractional parentage, and calculation of electronic states of molecular systems. A large number of tables, useful in actual calculations, is provided

  5. Probiotics as control agents in aquaculture

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

    2007-01-01

    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.

  6. New aquaculture drugs under FDA review

    Bowker, James D.; Gaikowski, Mark P.

    2012-01-01

    Only eight active pharmaceutical ingredients available in 18 drug products have been approved by the U.S. Food and Drug Administration for use in aquaculture. The approval process can be lengthy and expensive, but several new drugs and label claims are under review. Progress has been made on approvals for Halamid (chloramine-T), Aquaflor (florfenicol) and 35% PeroxAid (hydrogen peroxide) as therapeutic drugs. Data are also being generated for AQUI-S 20E, a fish sedative.

  7. Probiotics as Antiviral Agents in Shrimp Aquaculture

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

    2013-01-01

    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...

  8. Design of the BEPCII electron gun system

    BEPCII upgrading project needs a new high current electron gun. The design stage such as physical design, mechanical design and control system design of this new electron gun is described. The emission current is designed to be higher than 10 A for the pulse width of 1 ns with repetition rate of 50 Hz. The gun will operate with a pulsed high voltage power supply which can provide up to 200 kV high voltage. Computer simulations and optimizations have been carried out in the design stage, including the gun geometry and beam transport. EGUN and DGUN codes are used to simulate the gun geometry, and the results show that the perveance is about 0.22 ?A·V-3/2, and the emittance at gun exit is about 16 ?·mm·mrad. PARMELA code shows that the electron beam can be easily transported to the end of the first accelerating tube with a capture efficiency of 67% and root mean square emittance of 25 mm·mrad. New scheme of the gun control system based on EPICS is also presented. Two-bunch operation mode and 2.5 ?s long pulse operation mode are available in the control system. (authors)

  9. High Concentration of Red Clay as an Alternative for Antibiotics in Aquaculture.

    Jung, Jaejoon; Jee, Seung Cheol; Sung, Jung-Suk; Park, Woojun

    2016-01-28

    The use of antibiotics in aquaculture raises environmental and food safety concerns because chronic exposure of an aquatic ecosystem to antibiotics can result in the spread of antibiotic resistance, bioaccumulation of antibiotics in the organisms, and transfer of antibiotics to humans. In an attempt to overcome these problems, high-concentration red clay was applied as an alternative antibiotic against the following common fish pathogens: Aeromonas salmonicida, Vibrio alginolyticus, and Streptococcus equinus. The growth of A. salmonicida and V. alginolyticus was retarded by red clay, whereas that of S. equinus was promoted. Phase contrast and scanning electron microscopy analyses confirmed the attachment of red clay on cell surfaces, resulting in rapid gravitational removal and cell surface damage in both A. salmonicida and V. alginolyticus, but not in S. equinus. Different cell wall properties of grampositive species may explain the unharmed cell surface of S. equinus. Significant levels of oxidative stress were generated in only the former two species, whereas significant changes in membrane permeability were found only in S. equinus, probably because of its physiological adaptation. The bacterial communities in water samples from Oncorhynchus mykiss aquacultures supplemented with red clay showed similar structure and diversity as those from oxytetracycline-treated water. Taken together, the antibiotic effects of high concentrations of red clay in aquaculture can be attributed to gravitational removal, cell surface damage, and oxidative stress production, and suggest that red clay may be used as an alternative for antibiotics in aquaculture. PMID:26528535

  10. PESCA Instrument Digital Electronics and Control System

    Prieto, Manuel

    The PESCA Instrument has been designed and built with the purpose of studying the Solar Energetic Particles and the Anomalous Cosmic Rays from hydrogen to iron in the energy range 1.5-50 MeV/uma. The instrument will be part of the Russian PHOTON satellite payload. The instrument electronics system comprises two blocks: the analog block for the amplification process and the digital block for the data acquisition process. The hardware is based on MAS281 microprocessor and consists of two units, nominal and redundant, in order to prevent faults. The software and hardware control system are described.

  11. Risks of Using Antifouling Biocides in Aquaculture

    José Meseguer

    2012-02-01

    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.

  12. Risks of using antifouling biocides in aquaculture.

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

    2012-01-01

    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

  13. Probiotics as antiviral agents in shrimp aquaculture.

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

    2013-01-01

    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

  14. Probiotics in shrimp aquaculture: avenues and challenges.

    Ninawe, A S; Selvin, Joseph

    2009-01-01

    As an alternative strategy to antibiotic use in aquatic disease management, probiotics have recently attracted extensive attention in aquaculture. However, the use of terrestrial bacterial species as probiotics for aquaculture has had limited success, as bacterial strain characteristics are dependent upon the environment in which they thrive. Therefore, isolating potential probiotic bacteria from the marine environment in which they grow optimally is a better approach. Bacteria that have been used successfully as probiotics belong to the genus Vibrio and Bacillus, and the species Thalassobacter utilis. Most researchers have isolated these probiotic strains from shrimp culture water, or from the intestine of different penaeid species. The use of probiotic bacteria, based on the principle of competitive exclusion, and the use of immunostimulants are two of the most promising preventive methods developed in the fight against diseases during the last few years. It also noticed that probiotic bacteria could produce some digestive enzymes, which might improve the digestion of shrimp, thus enhancing the ability of stress resistance and health of the shrimp. However, the probiotics in aquatic environment remain to be a controversial concept, as there was no authentic evidence / real environment demonstrations on the successful use of probiotics and their mechanisms of action in vivo. The present review highlights the potential sources of probiotics, mechanism of action, diversity of probiotic microbes and challenges of probiotic usage in shrimp aquaculture. PMID:19514908

  15. Importation of aquaculture seedlings to Japan.

    Wakabayashi, H

    1996-06-01

    Japan is one of the largest consumers of fishery products in the world. Importation of various fishery commodities - including larvae and eggs for aquaculture - is increasing due to high consumer demand. Elvers of Anguilla anguilla have been imported from Europe since the late 1960s. Eyed eggs of coho salmon (Oncorhynchus kisutch) are imported from North America. During the last decade, over-production caused the price of Japanese amberjack (or 'yellowtail') (Seriola quinqueradiata) and Japanese seabream (Pagrus major) to drop, forcing farmers to venture into the culture of other species. A variety of marine fish seedlings are now imported from Asian countries. Almost all aquaculture production of coho salmon, greater amberjack (Seriola dumerili), seabass (Lateolabrax japonicus), rockfish (Sebastes spp.) and groupers (Epinephlus septemfaciatus, etc.) depends on imported seedlings. These species accounted for approximately 9% by value of marine finfish production in Japan in 1993. Apart from ubiquitous or endemic pathogens, a considerable number of exotic microorganisms and parasites are suspected to have accompanied fish eggs and larvae imported for aquaculture purposes. On a voluntary basis, 80-90% of imported salmon eggs are being examined for bacterial kidney disease and salmon viruses by semi-governmental organisation. Voluntary inspections are also being conducted on some other fish species imported from foreign countries. No legislation exists, however, for the control of exotic fish pathogens. PMID:8890372

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

    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...

  17. Emerging research priorities for the aquaculture sector in sub-Saharan Africa - a case study of Nigeria

    Kafayat A. Fakoya

    2009-10-01

    Full Text Available This paper reviews the role of aquaculture research in Nigeria. The achievements and limitations of research in aquaculture development are discussed. It identifies strategic prioritization of research objectives in three phases namely; the short term, medium term and long term to properly foster real growth in the aquaculture sector with the dawn of privatization in the country. Ex post assessments are also fundamental in evaluating the viability and effectiveness of past research activities. Participatory approach in research prioritization and process, increased private funding of research and extension, programmes of intervention by the government are required to maximize the untapped potentials in aquaculture for its rapid transformation to a full-fledged economically viable sector. Thus, profitable, sustainable ecological aquaculture and ‘water smart’ culture systems consistent with different geographical zones of the country must be designed with potentials for sequestration of anthropogenic carbon and nutrients. Adoption of Guidelines on Best Management and Practices in Aquaculture Schemes is a necessity. Above all is the question of an enabling institutional framework, autonomy and pragmatic sector - specific policies without which nothing can be realistically achieved.

  18. Electronic Integrated Disease Surveillance System and Pathogen Asset Control System

    Tom G. Wahl

    2012-06-01

    Full Text Available 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.

  19. Electronic integrated disease surveillance system and pathogen asset control system.

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

    2012-01-01

    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

  20. 14 CFR 221.300 - Discontinuation of electronic tariff system.

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Discontinuation of electronic tariff system... (AVIATION PROCEEDINGS) ECONOMIC REGULATIONS TARIFFS Electronically Filed Tariffs § 221.300 Discontinuation of electronic tariff system. In the event that the electronic tariff system is discontinued, or...

  1. Electronic system for Langmuir probe measurements

    Mitov, M.; Bankova, A.; Dimitrova, M.; Ivanova, P.; Tutulkov, K.; Djermanova, N.; Dejarnac, R.; Stöckel, J.; Popov, Tsv K.

    2012-03-01

    A newly developed Langmuir probe system for measurements of current-voltage (IV) characteristics in the tokamak divertor area is presented and discussed. The system is partially controlled by a computer allowing simultaneous and independent feeding and registration of signals. The system is mounted in the COMPASS tokamak, Institute of Plasma Physics, Academy of Sciences of the Czech Republic. The new electronic circuit boards include also active low-pass filters which smooth the signal before recording by the data acquisition system (DAQ). The signal is thus less noisy and the data processing is much easier. We also designed and built a microcontroller-driven waveform generator with resolution of 1 Ms/s. The power supply is linear and uses a transformer. We avoided the use of a switching power supply because of the noise that it could generate. Examples of measurements of the IV characteristics by divertor probes in the COMPASS tokamak and evaluation of the EEDF are presented.

  2. Meeting the Needs for More Fish Through Aquaculture

    Giap, D. H.; Lam, T. J.

    2015-10-01

    Fish is one of the major sources of animal protein. Due to rising world populations, increasing income and urbanization, demand for fish has been increasing. In order to meet the need for more fish, aquaculture has become increasingly important as wild populations and production from capture fisheries have declined due to overfishing and poor management. In recent years, production from aquaculture has increased rapidly to address the shortfalls in capture fisheries, especially in Asia where aquaculture production accounts for about 90% of world aquaculture production by volume. This paper reviews the status of the world’s fish production, provides an update on Asian aquaculture, and highlights developments that are contributing to sustainable fish production, particularly integrated multi-trophic aquaculture and aquaponics.

  3. Probiotic, a tool in livestock and aquaculture production

    Edgar Alberto López-Acevedo

    2013-06-01

    Full Text Available The probiotics are products based on different microorganism strains, those products have evolved from a just simple mixture of active bacteria to products with specific properties of adherence, colonization, synergies, antibacterial activity, etc. Probiotic products for livestock and aquaculture production are designed with strains developed to operate under specific conditions and which need to be understood and taken into account by the producers because different results can be observed depending of specie(s, geographic area, and type of culture production. The available information suggests that probiotic display a progress from: (a a better understanding of the bacterial micro-ecosystem and target organs, (b strain source and their particular characteristics, (c doses and target species, (d specific adhesion and/or colonization mechanisms, (e specific activation of the immune system, and, (f environmental effects. The aim of this manuscript is to provide information to the livestock and aquaculture producers about the characteristics and qualities of probiotic so they can carry out a proper selection and use.

  4. Scenarios for Resilient Shrimp Aquaculture in Tropical Coastal Areas

    Willem F. de Boer

    2010-06-01

    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.

  5. What shapes food value chains? Lessons from aquaculture in Asia

    Jespersen, Karen Sau; Kelling, I; Ponte, Stefano; Kruijssen, F

    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......, we reflect on the sustainability challenges of aquaculture and provide four broad observations on the governance of food value chains....

  6. L'aquaculture au Sénégal

    Belot, J.; Niamadio, I.

    1988-01-01

    Aquaculture in Senegal. Different projects of aquaculture in Senegal are reviewed. In Senegal, the productions in aquaculture are : culture of oysters in Joal Fadiouth (about 6, 000 dozens/year) a test of shrimp production (Penaeusj in Casamance, the first one in West Africa (0.5 T to 4.5 T/ha/year) culture of Tilapia nilotica long the Senegal river in the north and Anambe in the south. Problems about these projects are discussed.

  7. A study on rural women's empowerment through participation in aquaculture

    Rahman, M.H.

    2005-01-01

    The study was undertaken to understand the rural women's (i) extent of participation in some selected aquaculture practices and (ii) extent of empowerment through participation in aquaculture program. Data were collected from 200 selected rural women of two districts - Sherpur and Kishoreganj. Each of the families where the selected rural women who were involved in aquaculture under the supervision of two partner NGOs of DSAP, namely- Foundation for Human Development (FHD) and Center for Rura...

  8. L'aquaculture au Sénégal

    Belot, J.

    1988-01-01

    Full Text Available Aquaculture in Senegal. Different projects of aquaculture in Senegal are reviewed. In Senegal, the productions in aquaculture are : culture of oysters in Joal Fadiouth (about 6, 000 dozens/year a test of shrimp production (Penaeusj in Casamance, the first one in West Africa (0.5 T to 4.5 T/ha/year culture of Tilapia nilotica long the Senegal river in the north and Anambe in the south. Problems about these projects are discussed.

  9. Probiotics in aquaculture of China - Current state, problems and prospect

    Qi, Z.Z.; Zhang, X. H.; Boon, N.; Bossier, P

    2011-01-01

    The development of non-antibiotic and environmental friendly agents is one of the key factors for health management in aquaculture. The application of probiotics in aquaculture of China emerged in 1980s; subsequently, commercial probiotic products from USA, Japan and United Kingdom were introduced into China in the middle of 1990s and evaluation experiments were conducted in vivo. In the mean time, scientists in China started to screen for new probiotic strains from local aquaculture rearing ...

  10. Concepts of Highly Excited Electronic Systems

    Berakdar, Jamal

    2003-05-01

    Knowledge of the excitation characteristics of matter is decisive for the descriptions of a variety of dynamical processes, which are of significant technological interest. E.g. transport properties and the optical response are controlled by the excitation spectrum. This self-contained work is a coherent presentation of the quantum theory of correlated few-particle excitations in electronic systems. It begins with a compact resume of the quantum mechanics of single particle excitations. Particular emphasis is put on Green function methods, which offer a natural tool to unravel the relations between the physics of small and large electronic systems. The book contains explicit expressions for the Coulomb Green function of two charge particles and a generalization to three-body systems. Techniques for the many-body Green function of finite systems are introduced and some explicit calculations of the Green functions are given. Concrete examples are provided and the theories are contrasted with experimental data, when available. The second volume presents an up-to-date selection of applications of the developed concepts and a comparison with available experiments is made

  11. Mask Fabrication Using Electron Beam Exposure System

    Watakabe, Y.; Shigetomi, A.; Morimoto, H.; Kato, T.

    1981-07-01

    This study describes the results of feature size distribution, pattern location accuracy and level to level registration error on chrominum master masks fabricated by EeBES-40. This system has the capability of high speed electron beam blanking at 40MHz, the capacity for large size masks (with 6 inch mask cassette), and the automatic cassette handling system. OEBR-100(PGMA), as the electron beam negative resist, is used for 5 inch and 6 inch chrominum masks. The chrominum etching process is used for both wet and dry plasma technology. Test patterns and 64 K bit memory TEG, as the practical pattern, are used in this study. More than 40 measurements are taken, uniformly distributed over 96 to 112mm square, and the feature size distribution is measured by a laser interferometer X-Y measuring system. Pattern location accuracy and level to level registration error are obtained using EeBES-40 quality assurance programs called MARKET/PLOTMARKET. This program operates by scanning over the resist image of the test pattern, utilizing the normal fiducial mark location hardware. The followinc results are obtained; (1) Feature size distribution within 6 inch mask : -/+0.1 μm (2) Level-to-level registration error2 : less than 0.1 pm High quality masks with about 0.02 defects/cm2 , and rapid throughput of 6 hr./10 masks using the auto-matic 10-cassette handling system are obtained.

  12. Effects of electron-electron interactions on electronic transport in disordered systems

    This thesis is concerned with the role of electron-electron interactions on electronic transport in disordered systems. We first consider a novel non-linear sigma model in order to microscopically treat the effects of disorder and electronic interaction. We successfully reproduce the perturbative results for the zero-bias anomaly and the interaction correction to the conductivity in a weakly disordered system, and discuss possible directions for future work. Secondly we consider the fluctuations of the dephasing rate for a closed diffusive and quantum dot system. Using the Keldysh technique we derive an expression for the inelastic scattering rate with which we self-consistently obtain the fluctuations in the dephasing rate. For the diffusive regime we find the relative fluctuations is given by F ∼ (Lφ/L)2/g2, where g is the dimensionless conductance, Lφ is the dephasing length and L is the sample size. For the quantum dot regime we find a perturbative divergence due to the presence of the zero mode. By mapping divergent diagrams to those for the two-level correlation function, we conjecture the existence of an exact relation between the two. Finally we discuss the consequences of this relation. (author)

  13. New Electron Gun System for BEPCII

    Liu, Bo; Long Chi, Yun; Zhang, Chuang

    2005-01-01

    The new electron gun system for BEPCII has been put into operation since Nov. 2004. The article describes the design, experiment and operation of this new system. The design current of the gun is 10 A for the pulse lengths of 1 ns, 2.5 ns and 1 μs with repetition rate of 50 Hz. The gun is operated with a pulsed high voltage power supply which can provide up to 200 kV high voltage. Computer simulations have been carried out in the design stage, including simulation of the gun geometry and beam transportation. Some important relation curves are obtained during the experiment. Two-bunch operation is available and some elementary tests have been performed. New scheme of the gun control system based on EPICS is also presented. The real operation shows that the design and manufacturing is basically successful.

  14. Expert system for WDS Electron Probe Microanalysis

    The electron microprobe is a complex tool for elemental micro-characterisation. The expert system developed during this thesis is a software to help and to advice the operator and its aim is to simplify the procedures, to improve the accuracy of the results and to control the analysis time. The starting point of the system is an interactive questionnaire regarding the sample,( i.e. what is already known), and about the expectations on the analysis,( i.e. the accuracy of the results required by the operator). Then, the system performs a semi-quantitative analysis of the sample. Based on the acquisition of a wavelength qualitative spectrum, this method is a way to obtain the sample composition in a short time with a reasonable accuracy. The results at the end of this first phase give a good idea of the present elements and the sample composition. All the information obtained in this first step are necessary to the system to optimise all the parameters of an accurate quantitative measure. For this study, we developed specific algorithms of simulation, in particular the X radiation emitted by an unknown under the electron beam, and the response of the microprobe for this emission. Then, we have developed models to calculate the intensity, the shape of the x-ray lines and of the continuum as they would be measured by the microprobe. These models were validated by comparison with measures. Moreover, they are created to be adapted to all kind of microprobe. These simulations give to the system expert the possibility to consider all the analysis configurations for the tested sample and to optimise the microprobe parameters in agreement with the operator's expectations. The final configuration proposed by the expert system is the one which better satisfies the expectations and which needs the minimal time of measure for each point. (author)

  15. Hy914, an electronic equipment test system

    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)

  16. Structural dynamics of electronic and photonic systems

    Suhir, Ephraim; Steinberg, David S

    2011-01-01

    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

  17. Contact phenomena in 2D electron systems

    Shikin, Valeri; Teske, Ekkehard; Leiderer, Paul; Wyder, Peter

    1998-01-01

    A promising way ro investigate 2D contact phenomena is proposed. This method is based on the idea of depositing surface state electrons (SSE) on a thin layer of liquid helium covering the surface of a solid sample containing a 2D-charge carrier system. The density of SSE adjusts to screen contact-induced perturbations or the electrostatic potential across the sample. As a result, the helium layer thickness varies due to the variation of the electrostatic pressure, thus providing a map. This m...

  18. Electron scattering and few nucleon systems

    Recent result obtained by electron scattering in the few-nucleon systems (A 3He charge and magnetic form factors are discussed. New theoretical results indicate that three body forces improve considerably the saturation properties of 3He, 4He and nuclear matter, but are not able to reconcile experiment and theory for the charge form factors of 3He and 4He. Calculations of meson exchange effects with different theoretical approaches bring the theory into reasonable agreement with the experimental charge and magnetic form factor fo 3He. Recent results of the measurements of the two and three body break-up of 3He are discussed

  19. Electronic journal management systems experiences from the field

    Ives, Gary W

    2013-01-01

    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,

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

    Noble, M.

    1993-01-01

    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...

  1. Superconductivity and Strongly Correlated Electron Systems

    Scarpetta, G.; Noce, C.; Romano, A.

    1994-10-01

    The Table of Contents for the book is as follows: * Preface * Towards a theory of copper-oxides metals * The Mott transition: mean field theories and real materials * The boson-fermion scenario for high-Tc superconductivity * Bipolaronic Bose-liquid in high-Tc superconductors: arguments against and evidence for * Superconductivity and density waves in high dimensions * Theory of dynamical screening effects in the exciton and bipolaron formation: an application to strongly photoexcited semiconductors and to the bipolaron model for high-Tc superconductivity * On the NMR properties of the quasi-2D Heisenberg antiferromagnet doped with real space pairs * Composite operator method for strongly correlated electron systems * Second order approximation for optical polarons in the strong coupling case * Fermion-spin transformation and strong coupling behavior of two-coupled t-J chains * t-J model and quasiparticles in NiO and in CuO2 * Electronic structure and pairing of strongly correlated fermions: Fermi liquid versus spin liquid * A multiple-subband solution of the t-t'-J model * Novel symmetries in condensed matter physics: quantum symmetry and the Hubbard model with phonons * Hubbard models: a Quantum Monte-Carlo study * Electron-hole asymmetry in a generalized one-band Hubbard model * The Hubbard model as a paradigm for strongly correlated electron systems * A study of La2Cu1-cZncO4 with implications for Fermi liquid models of high temperature superconductivity * Analysis of the Hubbard model by composite operator method in a generalized mean field approximation * Condensed particle structure in the inhomogeneous BCS-model and a mean field Hubbard model * A field theoretical investigation of the Hubbard hamiltonian * Magnetic and non-magnetic states of heavy fermion systems * Kinematical mechanism of superconductivity in the periodic Anderson model * Correlation effects in high-Tc superconductors and heavy fermion compounds * Are anyons relevant to condensed matter? Maybe * Fractional statistics in 2+1 dimensional U(1)-scalar-Chern-Simons gauge field theory * Weak disorder and phase transitions in unconventional superconductors * Fluctuation effects in superconductors with random-field-like quenched disorder * oscopic quantum theoretic approach to superconductive electrodynamics

  2. Electronic systems associated with radiation detectors

    This article deals with the instrumentation used for the detection of radiations in nuclear reactors and fuel reprocessing plants. In power reactors, the control of nuclear fissions is performed with the measurement of the neutron flux emitted by the pressure vessel. In fuel reprocessing plants the quantities of nuclear material are controlled all along the process by the measurement of the neutrons and gamma photons emitted. The measurement systems use the information contained in the series of electrical pulses delivered by the detectors. The number of pulses and the particular characteristics of each pulse are the methods used in the two different classes of measurements performed in nuclear facilities. Measurement systems are particularly sensible to the signal/noise ratio which is a determining factor in the quality of measurements: 1 - sources of error and filtering of detector pulses: detectors and processing of pulses; sources of errors (electronic noise, thermal drift, electromagnetic disturbances, piling up effects, ballistic deficit); optimum estimation and filtering (optimum energy estimation, counting optimization); 2 - measurement chains associated with detectors: counting and measurement of weak currents (effect of the connection cable, effects of high counting rates, method of fluctuations and advantage of a numerical processing of the signal, measurement of weak currents, effect of radiations on electronic components); energy measurement (filter for energy measurements, design of low-noise preamplifiers, high counting rate measurements). (J.S.)

  3. Energy transformation in molecular electronic systems

    Our new optical pumping spectroscopy (steady state, and double-laser pulse) allows the production and study of the unstable rare tautomer in its ground and excited states, including picosecond dynamic studies. Molecules under study here included 7-azaindole (model for biological purines), 3-hydroxyflavone (model for plant flavones), lumichrome, and other heterocyclics. New detailed molecular mechanisms for proton transfer are derived, especially with catalytic assisting molecules. A new proton-transfer laser of extraordinary efficiency has become a side dividend, possibly worth of industrial development. The excited and highly reactive singlet molecular oxygen species 1Δ/sub g/) has proven to be ubiquitous in chemical peroxide systems and in physically excited sensitizer-oxygen systems. Hyperbaric oxygen mechanisms in biology probably involve singlet oxygen. We have undertaken a spectroscopic study of tris - dibenzoylmethane chelates of Al, Gd, Eu, and Yb trivalent ions. These chelates offer a variety of electronic behaviors, from Z-effects on π-electron spin-orbital coupling (Al, Gd) to Weissman intramolecular energy transfer to 4f mestable levels (Eu, Gd). Elegant new spectroscopic resolution at 77K permits separation of tautomeric, parasitic self-absorption, dissociation, and cage effects to be resolved. 18 refs., 4 figs

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

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

    2012-01-01

    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…

  5. Plasma Oscillations and Electron-Elecron Interactions in 2D Electron Systems

    Electron-electron interactions in a single highly doped heterojunction are considered taking into account both transitions. Expressions are derived for the time of electron-electron interaction, matrix elements of the full screening potential and dynamic dielectric function in 2D electron system with fine structure of energy spectrum, and for the electron density spatial distribution. The calculated dependences provide a good description of the experimental times of Landau levels collisional broadening.

  6. Beam position monitoring electronics system for LEHIPA

    The primary function of beam position monitoring system (BPM) is to determine the position of the beam with respect to the centre of beam pipe. The present system is VME based and mainly consists of two VME boards one Analog and one Digital. The system has been developed for 352.21 MHz Low Energy High Intensity Proton Accelerator (LEHIPA). The electronic system processes the signals coming from the sensor which incorporates four button pick-ups placed orthogonally around the beam pipe. The fundamental component of the beam signal is extracted from the signals from the sensor and amplified with gain stabilized amplifiers on the analog board. Offset tone based technique has been used for the stabilization of the gain of the amplifiers against changes in temperature, power supply, etc. The filtered and amplified signals are given to the digital board for digitization and further processing. The signal processing consists of demodulation in I-Q domain followed by CORDIC which gives the signal information in the form of amplitude and phase. The stabilization of the gain is also carried out in the digital domain. The phase information can be utilized for energy gain measurements. The amplitudes give the position of the beam which is calculated online in FPGA using difference over sum method. The EPICS system has been chosen as the basic framework for command control. The hardware architecture is as per standard VME crate. (author)

  7. Radiation Risks and Mitigation in Electronic Systems

    Todd, B

    2015-01-01

    Electrical and electronic systems can be disturbed by radiation-induced effects. In some cases, radiation-induced effects are of a low probability and can be ignored; however, radiation effects must be considered when designing systems that have a high mean time to failure requirement, an impact on protection, and/or higher exposure to radiat ion. High-energy physics power systems suffer from a combination of these effects: a high mean time to failure is required, failure can impact on protection, and the proximity of systems to accelerators increases the likelihood of radiation-induced events. This paper presents the principal radiation-induced effects, and radiation environments typical to high-energy physics. It outlines a procedure for designing and validating radiation-tolerant systems using commercial off-the-shelf components. The paper ends with a worked example of radiation-tolerant power converter controls that are being developed for the Large Hadron Collider and High Luminosity-Large Hadron Colli...

  8. Water Diagnosis in Shrimp Aquaculture based on Neural Network

    Carbajal Hernández, J. J.; Sánchez Fernández, L. P.

    2007-05-01

    In many countries, the shrimp aquaculture has not advanced computational systems to supervise the artificial habitat of the farms and laboratories. A computational system of this type helps significantly to improve the environmental conditions and to elevate the production and its quality. The main idea of this study is the creation of a system using an artificial neural network (ANN), which can help to recognize patterns of problems and their evolution in shrimp aquaculture, and thus to respond with greater rapidity against the negative effects. Bad control on the shrimp artificial habitat produces organisms with high stress and as consequence losses in their defenses. It generate low nutrition, low reproduction or worse still, they prearrange to acquire lethal diseases. The proposed system helps to control this problem. Environmental variables as pH, temperature, salinity, dissolved oxygen and turbidity have an important effect in the suitable growth of the shrimps and influence in their health. However, the exact mathematical model of this relationship is unspecified; an ANN is useful for establishing a relationship between these variables and to classify a status that describes a problem into the farm. The data classification is made to recognize and to quantify two states within the pool: a) Normal: Everything is well. b) Risk: One, some or all environmental variables are outside of the allowed interval, which generates problems. The neural network will have to recognize the state and to quantify it, in others words, how normal or risky it is, which allows finding trend of the water quality. A study was developed for designing a software tool that allows recognizing the status of the water quality and control problems for the environment into the pond.

  9. Treatment of Aquaculture Wastewater Using Floating Vegetated Mats

    Methods are needed for treating aquaculture wastewater. The goal is to improve wastewater quality sufficiently for it to be recycled to production ponds. One potential method for improving aquaculture wastewater is to use floating vegetation in treatment tanks. Alternatively, potential exists for ...

  10. 7 CFR 1437.303 - Aquaculture, including ornamental fish.

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Aquaculture, including ornamental fish. 1437.303... ASSISTANCE PROGRAM Determining Coverage Using Value § 1437.303 Aquaculture, including ornamental fish. (a... human consumption as determined by CCC. (2) Fish raised as feed for other fish that are consumed...

  11. Aqua-Topics. Aquaculture for Youth and Youth Educators.

    McVey, Eileen

    This booklet contains information on aquaculture and ideas for aquaculture projects. The information provided is for students at upper elementary through high school learning levels. Recommended activities at the end of the text are organized by level of difficulty. The activities can be modified depending on area and availability of resources. A…

  12. Guide to Using Drugs, Biologics, and Other Chemicals in Aquaculture

    The Guide to Using Drugs, Biologics, and Other Chemicals in Aquaculture (Guide) describes regulated products that are approved for use in U.S. aquaculture. The Guide also describes drugs that are not yet approved for use in the U. S. but that can be used under an Investigational New Animal Drug (INA...

  13. The Harry K. Dupree Stuttgart National Aquaculture Research Center

    Aquaculture is currently the fastest growing sector of global food production. Global aquaculture production in 2011 totaled 60 million tonnes (excluding aquatic plants) valued at US$119 billion, while global capture fishery production has remained static at approximately 90 million tonnes annually...

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

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

    1999-01-01

    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 Te double donor in...

  15. Economic Analysis on Key Challenges for Sustainable Aquaculture Development

    Gedefaw Abate, Tenaw

    Aquaculture (farming of aquatic organisms) has been the fastest-growing animal food-producing sector in the world during the last three decades. At present, more than half of the world’s human fish consumption comes from aquaculture. Despite the positive trend, the aquaculture industry faces...... challenges that could obstruct its sustainable development, such as a lack of suitable feed, which includes fishmeal, fish oil and live feed, and negative environmental externalities. If the aquaculture industry is to reach its full potential, it must be both environmentally and economically sustainable. To...... this end, key challenges should be thoroughly examined to identify sustainable and efficient solutions. Thus, the thesis focuses on two important bottlenecks in the growth of the aquaculture sector—namely, lack of nutritionally suitable live feed items for marine finfish production and negative...

  16. Mechanisms of antimicrobial resistance in finfish aquaculture environments

    PatriciaL.Keen

    2013-08-01

    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.

  17. Advanced Photonic and Electronic Systems WILGA 2010

    Romaniuk, R S

    2010-01-01

    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...

  18. CERN Sells its Electronic Document Handling System

    2001-01-01

    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...

  19. Electron beam accelerator energy control system

    A control system has been developed for the energy control of the electron beam accelerator using PLC. The accelerating voltage of 3 MV has been obtained by using parallel coupled voltage multiplier circuit. A autotransformer controlled variable 0-10 KV DC is fed to a tube based push pull oscillator to generate 120 Khz, 10 KV AC. Oscillator output voltage is stepped up to 0-300 KV/AC using a transformer. 0-300 KVAC is fed to the voltage multiplier column to generate the accelerating voltage at the dome 0-3 MV/DC. The control system has been designed to maintain the accelerator voltage same throughout the operation by adjusting the input voltage in close loop. Whenever there is any change in the output voltage either because of beam loading or arcing in the accelerator. The instantaneous accelerator voltage or energy is a direct proportional to 0-10 KVDC obtained from autotransformer. A PLC based control system with user settable energy level has been installed for 3 MeV, EB accelerator. The PLC takes the user defined energy value through a touch screen and compares it to the actual accelerating voltage (obtained using resistive divider). Depending upon the error the PLC generates the pulses to adjust the autotransformer to bring the actual voltage to the set value within the window of error (presently set to +/- 0.1%). (author)

  20. Practical dc SQUID system: Devices and electronics

    Zhang, Guofeng; Zhang, Yi; Hong, Tao; Wang, Hai; Krause, Hans-Joachim; Xie, Xiaoming

    2015-11-01

    In order to set up a liquid helium-cooled practical dc SQUID system with acceptable noise figure, we employ a weakly damped dc SQUID with a large flux-to-voltage transfer coefficient ∂V/∂V in a direct readout scheme (DRS) without flux modulation. Two preamplifiers are utilized: (1) AD 797 for a so-called "single chip readout electronics" (SCRE); (2) 6 parallel-connected bipolar transistors (PCBT). The latter reduces the preamplifier voltage noise Vn but increases its current noise In, which plays a leading role in the system low-frequency noise. We introduce a current feedback circuit (CFC) consisting of an inductor Li coupled to the SQUID with mutual inductance Mi to improve the noise performance. In this work, the preamplifier In contribution and CFC are analyzed. To evaluate the In suppression with CFC, two criteria are presented. Furthermore, we establish a dimensionless parameter ξ to describe CFC quantitatively. The system noise is compared with and without CFC using the two preamplifiers. For a dc SQUID with a loop inductance of 350 pH, an intrinsic noise of about 5 μV0/√Hz and a corner frequency at 2 Hz are measured using PCBT with CFC.

  1. Fisheries And Aquaculture Resources And Their Interactions With Environment in Turkey

    Deniz, H.

    2003-04-01

    Turkey, with 8333 km of coast line, 151 080 sq. km economic sea area, many rivers with 177 714 total length, nearly, 1 million ha of natural lakes, 500 000 ha of dam reservoirs has rich marine and inland aquatic resource potential. Despite of these large resources, Turkish fisheries has the characteristics of small-scale fisheries and in general it can be considered as coastal fisheries. There is also great potential for inland fisheries and aquaculture. Being in half closed position, these seas have different characteristics in respect of biological, physical, chemical and ecological points. In addition; Turkey has favourable geographic position between the Black Sea and Mediterranean Sea. Nevertheless, this potential seems not to be fully utilised and therefore fisheries is not a major sector in the economy. According to the statistics of the fisheries for 2000 published by the Turkish government, Turkey's total fisheries production was 582.376 tons. Total catch consists sea fish (441 690 tons, crustaceans and molluscs (18 831 tons), freshwater fish (42.824 tons) and aquaculture (79. 031 tons). The Ministry of Agriculture and Rural Affairs (MARA) is the Ministry responsible for the overall fisheries and aquaculture development, administration, regulation, promotion and technical assistance. In the past two decades, marine fish farming using net cages has developed in the coastal waters throughout Turkey. Such fish farming has allowed the production of large amounts of valuable fish and their supply to the internal and external markets on a regular basis. However, fish farming is sometimes fallowed by organic pollution of the water and bottom sediment in the vicinity of the cages. A comprehensive land and coastal planning survey of almost the whole coast of Turkey is currently being conducted. This master plan designates areas to be developed for forestry, agriculture, industry, urbanisation, environmentally protected areas, etc. The plan was undertaken before the potential of aquaculture was fully realised and there were, therefore, no areas specifically designated for aquaculture. Aquaculture development is therefore being restricted by the loss of access to some of the best sites. The most common conflicts occur with environmental protection, tourism, recreation, urbanisation, archaeology and navigation. In order to prevent such conflicts and minimise the environmental impacts the open sea fishery, offshore mariculture systems, and echo-friendly technologies have to be adopted. In addition to that integrated coastal management models must be developed and implemented. Key words: fisheries and aquaculture resources, environment, interaction, tourism, protected areas, mangement and sustainability.

  2. Genomic Approaches in Marine Biodiversity and Aquaculture

    Jorge A, Huete-Pérez; Fernando, Quezada.

    Full Text Available 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.

  3. Genomic Approaches in Marine Biodiversity and Aquaculture

    Jorge A Huete-Pérez

    2013-01-01

    Full Text Available 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.

  4. Experimental system of ejected electron spectroscopy with ECR ion source

    The experiment of analyzing energy spectrum of electrons ejected from multiple electron capture process on ion-atom collision is carried out using ECR (Electron Cyclotron Resonance) ion source. An old collision system using gas atoms as target and a new system using vapour atoms are developed. In this report, the developments and exploitations of the experimental systems for the ejected electron spectroscopy with ECR Ion source are presented. (author)

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

    Schmitt, Laetitia Helene Marie; Brugere, Cecile

    2013-01-01

    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

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

    Daudi S. Simbeye

    2014-04-01

    Full Text Available 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 platform. The water quality parameters will be sent to owners through short messages from the base station via the Global System for Mobile (GSM module for notification. The experimental evaluation of the network performance metrics of quality of communication link, battery performance and data aggregation was presented. The experimental results show that the system has great prospect and can be used to operate in real world environment for optimum control of aquaculture environment

  7. Parallel data acquisition system for electron momentum spectrometer

    Pang, W N

    1999-01-01

    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)

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

    Daudi S. Simbeye; Shi Feng Yang

    2014-01-01

    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...

  9. Development of integrated aquaculture : agriculture with brackish and salt water, Egypt

    Heijden, P.G.M. van der; Blom-Zandstra, G.; Sadek, S.; Elsamadony, E.; Eweas, M.; El-Dib, H.; Sabry, M.

    2013-01-01

    This report describes the development of an integrated saltwater aquaculture – agriculture farming system at Wadi El Natroun, Egypt. During the first two years of the project promising salt-tolerant plant species were identified, the methods for seed germination and growing of three salt-tolerant plant species with potential for human consumption and animal fodder were developed, and the culture of red tilapia in a so-called biofloc system with salt water was tested. Report number CDI-13-004

  10. Electron-electron interactions in a weakly screened two-dimensional electron system

    Karakurt, I.; Dahm, A. J.

    2002-01-01

    We probe the strength of electron-electron interactions using magnetoconductivity measurements of two-dimensional non-degenerate electrons on liquid helium at 1.22 K. Our data extend to electron densities that are two orders of magnitude smaller than previously reported. We span both the independent-electron regime where the data are qualitatively described by the self-consistent Born approximation (SCBA), and the strongly-interacting electron regime. At finite fields we observe a crossover f...

  11. Electron-optical systems for planar gyrotrons

    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

  12. Development of the electron gun control system of SSRF

    An electron gun is the key part of a linac, the beam quality of which depends on beam quality of the electron gun, hence the need of a stable control system of the electron gun to ensure its safe operation.In this paper, we report our progresses in developing the linac's electron gun control system of Shanghai Synchrotron Radiation Facility (SSRF). It uses PLC as the device controllers, with the monitoring software developed on EPICS. The whole system is connected by Ethernet. The PLC and Ethernet technology ensures good reliability and easy maintenance of the electron gun control system. (authors)

  13. Halophyte filter beds for treatment of saline wastewater from aquaculture.

    Webb, J M; Quintã, R; Papadimitriou, S; Norman, L; Rigby, M; Thomas, D N; Le Vay, L

    2012-10-15

    The expansion of aquaculture and the recent development of more intensive land-based marine farms require efficient and cost-effective systems for treatment of highly nutrient-rich saline wastewater. Constructed wetlands with halophytic plants offer the potential for waste-stream treatment combined with production of valuable secondary plant crops. Pilot wetland filter beds, constructed in triplicate and planted with the saltmarsh plant Salicornia europaea, were evaluated over 88 days under commercial operating conditions on a marine fish and shrimp farm. Nitrogen waste was primarily in the form of dissolved inorganic nitrogen (TDIN) and was removed by 98.2 ± 2.2% under ambient loadings of 109-383 μmol l(-1). There was a linear relationship between TDIN uptake and loading over the range of inputs tested. At peak loadings of up to 8185 ± 590 μmol l(-1) (equivalent to 600 mmol N m(-2) d(-1)), the filter beds removed between 30 and 58% (250 mmol N m(-2) d(-1)) of influent TDIN. Influent dissolved inorganic phosphorus levels ranged from 34 to 90 μmol l(-1), with 36-89% reduction under routine operations. Dissolved organic nitrogen (DON) loadings were lower (11-144 μmol l(-1)), and between 23 and 69% of influent DON was removed during routine operation, with no significant removal of DON under high TDIN loading. Over the 88-day study, cumulative nitrogen removal was 1.28 mol m(-2), of which 1.09 mol m(-2) was retained in plant tissue, with plant uptake ranging from 2.4 to 27.0 mmol N g(-1) dry weight d(-1). The results demonstrate the effectiveness of N and P removal from wastewater from land-based intensive marine aquaculture farms by constructed wetlands planted with S. europaea. PMID:22818948

  14. Gender training in aquaculture in northern Vietnam. A report.

    Voeten, J; Ottens, B J

    1997-01-01

    Described is a pilot project that integrated gender and technology in training and analysis in Vietnam. Many farmers in Vietnam use the VAC system of fishing, farming, and animal husbandry, which makes efficient use of resources and requires low inputs. Excess products are sold locally. Plants are used for food, fiber, and fuel. Waste products are recycled. Small ponds (under 0.5 ha) are created using rainwater. 2-8 tons/ha/year of fish are produced. The dug-out soil is used to build up gardens and house foundations as protection against flooding. Fresh water for the household comes from wells. Garden plots contain various intercropped species. Fruit trees and tuber crops are cultivated in shady areas. Timber trees and rattan are planted to form tree fences. Taro is planted around the ponds, and marsh lentils are planted on pond surfaces. Various fish feed in the top, middle, and bottom portions of ponds. Gourd is grown on trellises above the ponds. Pig manure is used for plant and fish food. Pond water, which is rich in nutrients and sludge, is used to fertilize gardens. During 1995-96, a pilot program provided training in aquaculture for poor rural women in the villages of My Xa and My Tan in Nam Ha province and Tuan Chinh and Yen Dong in Vihn Phu province in the north. The analysis identified gender relations in management, control of aquaculture, decision-making, and use of benefits. The concept of gender was explained to women in the training program. Women were more concerned with the technical training. The position of women improved in participation, decision-making, and control over benefits. The technical transfer of knowledge was viewed as less important than gender awareness. The aim to improve women's position should be clearly identified. Community participation in the training of trainers was beneficial. Follow-up activities continued during 1997-99. PMID:12179940

  15. T-3 electron-beam-excited laser system

    Klein, R A

    1981-02-01

    A laser system specifically designed to study the kinetics of electron-beam driven systems is described. Details of the system are given along with measurements of the electron-beam uniformity and deposition in the laser medium. Some HF laser results obtained with this system are also given.

  16. Enhancement of existing geothermal resource utilization by cascading to intensive aquaculture

    Zachritz, W.H. II; Polka, R.; Schoenmackers, R.

    1995-12-04

    Aquaculture, the farming and husbandry of freshwater and marine organisms, is the newest and fastest growing US agricultural sector. In New Mexico, low winter temperatures and limited freshwater sources narrow culture production possibilities; however, it has long been recognized that the state has abundant supplies of both saline and geothermal ground waters. The purpose of this project was to demonstrate the achievable energy savings and value enhancement of the byproduct geothermal energy by cascading fluids for the production of commercial aquaculture species. Specifically the project involved evaluating the heating systems performance in terms of heating budget for the geothermal assist, determine the total quantity of water used for culture and heating, amount of geothermal byproduct heat extracted, and ability of the system to maintain culture water temperatures during critical heating periods of the year. In addition, an analysis was conducted to determine the compatibility of this new system with existing greenhouse heating requirements.

  17. Power electronic converters and systems frontiers and applications

    Trzynadlowski, Andrzej M

    2016-01-01

    Power electronics is a branch of electrical engineering dealing with conversion and control of electric power using semiconductor power switches. This book provides an overview of modern power electronic converters and systems, and their applications.

  18. Cyclotron spin-wave in the 2D electron system

    Kulik, L V; Kirpichev, V E; Smet, J H; Klitzing, K V; Umansky, V; Wegscheider, W

    2001-01-01

    The cyclotron spin-wave mode of a two-dimensional electron system have been investigated by inelastic light scattering. It is observed at small electron filling factors of the Landau level (nu approx 0.1) when the electron system is spin-depolarized. As long as the electron system becomes fully spin-polarized (nu > 0.2) the cyclotron spin-wave disappears from the inelastic light scattering spectra. It reenters at electron filling factors nu > 1. Over the range of electron filling factors of 1 < nu < 2 the cyclotron spin-wave energy is insensitive to both the experimentally accessible momenta and the electron concentration, whereas inelastic light scattering efficiency is strongly influence by the spin polarization of the electron system

  19. Antibacterial Resistance in African Catfish Aquaculture: a Review

    Madubuike U. ANYANWU

    2016-03-01

    Full Text Available Antibacterial resistance (AR is currently one of the greatest threats to mankind as it constitutes health crisis. Extensive use of antibacterial agents in human and veterinary medicine, and farm crops have resulted in emergence of antibacterial-resistant organisms in different environmental settings including aquaculture. Antibacterial resistance in aquaculture is a serious global concern because antibacterial resistance genes (ARGs can be transferred easily from aquaculture setting to other ecosystems and the food chain. African catfish (ACF aquaculture has increased at a phenomenal rate through a continuous process of intensification, expansion and diversification. Risk of bacterial diseases has also increased and consequently there is increased use of antibacterial agents for treatment. Antibacterial resistance in ACF aquaculture has huge impact on the food chain and thus represents risk to public and animal health. In “one health” approach of curbing AR, knowledge of the sources, mechanisms and magnitude of AR in ACF aquaculture and its potential impact on the food chain is important in designing and prioritizing monitoring programs that may generate data that would be relevant for performing quantitative risk assessments, implementation of antibacterial stewardship plans, and developing effective treatment strategies for the control of ACF disease and reducing risk to public health. This review provides insight on the sources, mechanisms, prevalence and impact of antibacterial resistance in ACF aquaculture environment, a setting where the impact of AR is neglected or underestimated.

  20. Key Performance Characteristics of Organic Shrimp Aquaculture in Southwest Bangladesh

    Christian Reinhard Vogl

    2012-05-01

    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.

  1. Aquaculture Asia, Vol.13, No.1, pp.1-56, January-March 2008

    2008-01-01

    Developing guidelines for sustainable freshwater aquaculture planning in Vietnam. Aquaculture production, certification and trade: Challenges and opportunities for the small-scale farmer in Asia. The successful development of backyard hatcheries for crustaceans in Thailand. Alternate carp species for diversification in freshwater aquaculture in India. Genetic and reproduction technologies for enhanced aquaculture and fisheries management of Murray cod. Effluent and disease...

  2. Photoinduced electron transfer in model systems of photosynthesis.

    Hofstra, U.

    1988-01-01

    This Thesis describes Investigations on photoinduced electron transfer (ET) for several compounds, serving as model systems of the natural photosynthesis. In addition, the properties of the systems, e.g. the conformation in solution and the electronic properties of the photoexcited states are treated.Chapter 2 discusses present theories of photoinduced electron transfer. The following factors appear to effect the electron transfer rate constants:- donor-acceptor distance- nature of the linkin...

  3. Electron-electron interactions in a weakly screened two-dimensional electron system

    Karakurt, I

    2002-01-01

    We probe the strength of electron-electron interactions using magnetoconductivity measurements of two-dimensional non-degenerate electrons on liquid helium at 1.22 K. Our data extend to electron densities that are two orders of magnitude smaller than previously reported. We span both the independent-electron regime where the data are qualitatively described by the self-consistent Born approximation (SCBA), and the strongly-interacting electron regime. At finite fields we observe a crossover from SCBA to Drude theory as a function of electron density.

  4. Electronic Resource Management System. Vernetzung von Lizenzinformationen

    Michaela Selbach

    2014-12-01

    Full Text Available In den letzten zehn Jahren spielen elektronische Ressourcen im Bereich der Erwerbung eine zunehmend wichtige Rolle: Eindeutig lässt sich hier ein Wandel in den Bibliotheken (fort vom reinen Printbestand zu immer größeren E-Only-Beständen feststellen. Die stetig wachsende Menge an E-Ressourcen und deren Heterogenität stellt Bibliotheken vor die Herausforderung, die E-Ressourcen effizient zu verwalten. Nicht nur Bibliotheken, sondern auch verhandlungsführende Institutionen von Konsortial- und Allianzlizenzen benötigen ein geeignetes Instrument zur Verwaltung von Lizenzinformationen, welches den komplexen Anforderungen moderner E-Ressourcen gerecht wird. Die Deutsche Forschungsgemeinschaft (DFG unterstützt ein Projekt des Hochschulbibliothekszentrums des Landes Nordrhein-Westfalen (hbz, der Universitätsbibliothek Freiburg, der Verbundzentrale des Gemeinsamen Bibliotheksverbundes (GBV und der Universitätsbibliothek Frankfurt, in dem ein bundesweit verfügbares Electronic Ressource Managementsystem (ERMS aufgebaut werden soll. Ein solches ERMS soll auf Basis einer zentralen Knowledge Base eine einheitliche Nutzung von Daten zur Lizenzverwaltung elektronischer Ressourcen auf lokaler, regionaler und nationaler Ebene ermöglichen. Statistische Auswertungen, Rechteverwaltung für alle angeschlossenen Bibliotheken, kooperative Datenpflege sowie ein über standardisierte Schnittstellen geführter Datenaustausch stehen bei der Erarbeitung der Anforderungen ebenso im Fokus wie die Entwicklung eines Daten- und Funktionsmodells. In the last few years the importance of electronic resources in library acquisitions has increased significantly. There has been a shift from mere print holdings to both e- and print combinations and even e-only subscriptions. This shift poses a double challenge for libraries: On the one hand they have to provide their e-resource collections to library users in an appealing way, on the other hand they have to manage these collections efficiently. Not only libraries, but also the negotiators of Alliance and National Licences need a software application which helps them to handle these complex licences efficiently. The project presented in this paper aims at developing a national Electronic Resource Management System (ERMS. It is funded by the German Research Foundation/Deutsche Forschungsgemeinschaft (DFG. The project partners are the North Rhine-Westphalian Library Service Centre (hbz, the University Library Johann Christian Senckenberg Frankfurt, the Head Office of the Gemeinsamer Bibliotheksverbund (GBV and the Freiburg University Library. The projected ERMS  will provide a software system with a central knowledge base which supports a unified overview of licence data with a local, regional and national scope. In the current state of development, the focus is on data and function modelling and on designing concepts for rights management, cooperative data management, implementation of interface standards and the intended services such as statistical analyses.

  5. Unified thoery of strongly correlated electron systems

    Liu, Yu-Liang

    2000-01-01

    In framework of eigen-functional bosonization method, we introduce an imaginary phase field to uniquely represent electron correlation, and demonstrate that the Landau Fermi liquid theory and the Tomonaga-Luttinger liquid theory can be unified. It is very clear in this framework that the Tomonaga-Luttinger liquid behavior of one-dimensional interacting electron gases originates from their Fermi structure, and the non-Landau-Fermi liquid behavior of 2D interacting electron gases is induced by ...

  6. Local electronic properties in nanoscale systems

    Souza, Andre M. C.; Herrmann, Hans

    2007-01-01

    The local electronic structure on nanoscale chains is investigated theoretically. We propose a mechanism to explain the even-odd oscillation of length distribution of atom chains. We study the spatial peak structure as obtained by scanning tunneling microscopy (STM) constant-current topography as a function of the electron-electron interaction, band filling and temperature. The site-dependent magnetic moment is also examined.

  7. Electron trapping data storage system and applications

    Brower, Daniel; Earman, Allen; Chaffin, M. H.

    1993-01-01

    The advent of digital information storage and retrieval has led to explosive growth in data transmission techniques, data compression alternatives, and the need for high capacity random access data storage. Advances in data storage technologies are limiting the utilization of digitally based systems. New storage technologies will be required which can provide higher data capacities and faster transfer rates in a more compact format. Magnetic disk/tape and current optical data storage technologies do not provide these higher performance requirements for all digital data applications. A new technology developed at the Optex Corporation out-performs all other existing data storage technologies. The Electron Trapping Optical Memory (ETOM) media is capable of storing as much as 14 gigabytes of uncompressed data on a single, double-sided 54 inch disk with a data transfer rate of up to 12 megabits per second. The disk is removable, compact, lightweight, environmentally stable, and robust. Since the Write/Read/Erase (W/R/E) processes are carried out 100 percent photonically, no heating of the recording media is required. Therefore, the storage media suffers no deleterious effects from repeated Write/Read/Erase cycling.

  8. Raft River aquaculture project. Final report

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

    1980-07-01

    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.

  9. Potential application of microbial phytase in aquaculture

    Christopher M. A. Caipang

    2011-06-01

    Full Text Available Phytases are histidine acid phosphatases that catalyze the hydrolysis of phytic acid toinorganic phosphorus and myo-inositol phosphates. The phosphorus that is being released is used invarious metabolic processes. These enzymes are able to promote the growth of animals and plants aswell as increase the nutritional value of feedstuffs through dephytinization. Phytases are widespread innature because they are found in animals, plants and microorganisms. This paper discusses the differentmicrobial phytases that have been characterized and their beneficial roles in aquaculture. In order to beincorporated in the feed, microbial phytases must have the ability to withstand high temperatures duringprocessing, and to be stable in the gastrointestinal tract of the fish, the enzymes must be active at lowpH levels. The various effects of microbial phytases on the bioavailability of phosphorus in fish, ongrowth performance, on the immune responses, on the excretion of phosphorus and on the environmentare also reviewed.

  10. THE FISHERIES AND AQUACULTURE COMPONENT OF RURAL DEVELOPMENT

    Adrian ZUGRAVU

    2006-01-01

    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.

  11. Development of High Power Electron Beam Measuring and Analyzing System for Microwave Vacuum Electron Devices

    Ruan, C. J.; Wu, X. L.; Li, Q. S.; Li, C. S.

    The measurement and analysis of high power electron beam during its formation and transmission are the basic scientific problems and key techniques for the development of high performance microwave vacuum electron devices, which are widely used in the fields of military weapon, microwave system and scientific instruments. In this paper, the dynamic parameters measurement and analysis system being built in Institute of Electronics, Chinese Academy of Sciences (IECAS) recently are introduced. The instrument are designed to determine the cross-section, the current density, and the energy resolution of the high power electron beam during its formation and transmission process, which are available both for the electron gun and the electron optics system respectively. Then the three dimension trajectory images of the electron beam can be rebuilt and display with computer controlled data acquisition and processing system easily. Thus, much more complicated structures are considered and solved completely to achieve its detection and analysis, such as big chamber with 10-6 Pa high vacuum system, the controlled detector movement system in axis direction with distance of 600 mm inside the vacuum chamber, the electron beam energy analysis system with high resolution of 0.5%, and the electron beam cross-section and density detector using the YAG: Ce crystal and CCD imaging system et al. At present, the key parts of the instrument have been finished, the cross-section experiment of the electron beam have been performed successfully. Hereafter, the instrument will be used to measure and analyze the electron beam with the electron gun and electron optics system for the single beam and multiple beam klystron, gyrotron, sheet beam device, and traveling wave tube etc. thoroughly.

  12. Electron scattering and few-nucleon systems

    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

  13. Implementing CORAL: An Electronic Resource Management System

    Whitfield, Sharon

    2011-01-01

    A 2010 electronic resource management survey conducted by Maria Collins of North Carolina State University and Jill E. Grogg of University of Alabama Libraries found that the top six electronic resources management priorities included workflow management, communications management, license management, statistics management, administrative…

  14. Towards environmentally sustainable aquaculture: Exploiting fermentation products from anaerobic sludge digestion for fueling nitrate removal in RAS

    Suhr, Karin Isabel; Pedersen, Per Bovbjerg

    2011-01-01

    storage basins, to fuel denitrification in specific denitrification filters. In experimental filters (5.5 m3) nitrate-containing outlet water was mixed with drainage water from the sludge storage basins according to a factorial design varying C/N ratio from 4 to 12 (CODs /NO3-N) and hydraulic retention......Aquaculture is the world’s fastest growing food production sector (FAO, 2007). The continuous growth in many countries, however, relies heavily on the ability to reduce the emission of nutrients and chemicals from the fish farms. A way to manage and treat the nutrient aquaculture wastes is by...... production in recirculating aquaculture systems (RAS). In Denmark, more than 50 % of total fresh-water rainbow trout production is made in semi-intensive RAS, called ModelTroutFarms (MTF). MTF efficiently removes organic matter (93%), phosphorous (76%), and nitrogen (50%) (Svendsen et al., 2008). This makes...

  15. CHANGING PHENOMENON OF AQUACULTURE LAND THROUGH SPACE AND TIME USING GEOINFORMATICS TECHNIQUES: A CASE STUDY OF MOYNAAND NANDAKUMAR BLOCK, PURBA MEDINIPUR, WEST BENGAL, INDIA

    Nirupam Acharyya

    2015-03-01

    Full Text Available Aquaculture basically known as aqua farming that means the farming of aquatic organisms such as fish. This can be considered a sustainable land use in the same way as like the conventional terrestrial agriculture.It involves with raising fish commercially in tanks, ponds which is mainly for nutrition. Which is a highly regulated industry, and these regulations may well keep fish farming. Numbers of peoples are becoming dependent on the aquaculture system. Fundamentally, agricultural land provides space and opportunities for livelihood systems,however in many ways peoples are over-exploited land and water resources. In the present study an attempt has been made to identification and quantification of aquaculture zone occurring in the inland area of Moyna and Nandakumar Block, Purba Medinipur, West Bengal, India by using space-born Remote Sensing (RS technology, which has a good potentiality for change detection and good data availability and is consequently; well suited for the monitoring of land use change over a gap time period. The benefits of Geographic Information Systems (GIS application in aquaculture have promoted its quick expansion and as a most advantage to compare with the ground reality. The present study describes an efficient and scientific approach for aquaculture changing phenomenon with suitable illustrations of map to point out insight the respect of ground reality. The aquaculture area is delineated from satellite images through image processing technique and aquaculture zone are specially highlighted from spatially high resolution satellite images. Finally the study can shows that, the agriculture lands are highly vulnerable due to regular flooding and that land specially converted to aquaculture land

  16. Power electronic converter systems for direct drive renewable energy applications

    Chen, Zhe

    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.......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....

  17. Hydrocyclonic separation of invasive New Zealand mudsnails from an aquaculture water source

    Nielson, R. Jordan; Moffitt, Christine M.; Watten, Barnaby J.

    2012-01-01

    Invasive New Zealand mudsnails (Potamopyrgus antipodarum, NZMS) have infested freshwater aquaculture facilities in the western United States and disrupted stocking or fish transportation activities because of the risk of transporting NZMS to naive locations. We tested the efficacy of a gravity-fed, hydrocyclonicseparation system to remove NZMS from an aquaculture water source at two design flows: 367 L/min and 257 L/min. The hydrocyclone effectively filtered all sizes of snails (including newly emerged neonates) from inflows. We modeled cumulative recovery of three sizes of snails, and determined that both juvenile and adult sized snails were transported similarly through the filtration system, but the transit of neonates was faster and similar to the transport of water particles. We found that transit times through the filtration system were different between the two flows regardless of snail size, and the hydrocyclone filter operated more as a plug flow system with dispersion, especially when transporting and removing the larger sized adult and juvenile sized snails. Our study supports hydrocyclonic filtration as an important tool to provide snail free water for aquaculture operations that require uninfested water sources.

  18. Aquaculture Asia, Vol 12, No. 1, pp.1-51, January-March 2007

    2007-01-01

    Aquaculture Asia is a magazine for farmers and aquaculture-related service industries. Articles cover all aspects of aquaculture and the related processing, marketing, economic, environmental and social issues that surround the industry, with regular sections on sustainable aquaculture, marine finfish aquaculture, aquatic animal health, research and farming techniques and the NACA Newsletter. Emphasis is placed on the practical outcomes of research that are of direct benefit to the industry, ...

  19. Aquaculture Asia, vol. 12, no. 3, pp.1-52, July-September 2007

    2007-01-01

    Aquaculture Asia is a magazine for farmers and aquaculture-related service industries. Articles cover all aspects of aquaculture and the related processing, marketing, economic, environmental and social issues that surround the industry, with regular sections on sustainable aquaculture, marine finfish aquaculture, aquatic animal health, research and farming techniques and the NACA Newsletter. Emphasis is placed on the practical outcomes of research that are of direct benefit to the industry, ...

  20. Aquaculture Asia, vol. 12, no. 2, pp.1-50, April-June 2007

    2007-01-01

    Aquaculture Asia is a magazine for farmers and aquaculture-related service industries. Articles cover all aspects of aquaculture and the related processing, marketing, economic, environmental and social issues that surround the industry, with regular sections on sustainable aquaculture, marine finfish aquaculture, aquatic animal health, research and farming techniques and the NACA Newsletter. Emphasis is placed on the practical outcomes of research that are of direct benefit to the industry, ...

  1. Feasibility analysis of the utilization of moderator heat for agricultural and aquacultural purposes, Bruce nuclear power development

    A study is presented of the feasibility of using moderator reject heat from the Bruce nuclear power development either to heat greenhouses or to aid in a warm water hatchery or aquaculture operation. The study examines heat extraction and delivery plans, reliability of supply, pricing schedules, the Ontario greenhouse industry, site selection criteria, water transmission and distribution, costs, approvals required, and a construction timetable. Total system analysis shows that a greenhouse facility would be viable but the aquaculture/hatchery scheme is more cost-effective. (E.C.B.)

  2. Establishment of a mobile electron beam treatment system

    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)

  3. Correlation effects in 2-dimensional electron systems : composite fermions and electron liquid crystals

    Göres, Jörn

    2004-01-01

    The discovery of the Fractional Quantum Hall Effect (FQHE) and its explanation brought the importance of electron-electron correlation effects in 2-dimensional electron systems into focus. Correlations often dominate the physics of clean 2DES subjected to a strong perpendicular magnetic field, because the kinetic degrees of freedom are effectively frozen out. Up to this day, the complicated collective phenomena that arise from electron correlations remain a challenging subject of research thr...

  4. The Use of Garlic (Allium sativum) as a Growth Promoter in Aquaculture

    Suat Dikel

    2015-01-01

    The wide-ranging use of antibiotics and medicaments has resulted in chemical residue and resistant pathogens in cured fish. Chemical residue not only pollutes the environment, but also threatens consumer’s health. On the contrary, garlic as a well-known natural antibiotic that causes no environmental or physical side effects has shown to be effective for the treatment of many diseases in humans and animals. In aquaculture applications, garlic promotes growth, improves the immune system, stimu...

  5. The Multi-level Environmental Governance of Vietnamese Aquaculture: Global Certification, National Standards, Local Cooperatives

    Pham, T.A.; Bush, S.R.; Mol, A.P.J.; Kroeze, C.

    2011-01-01

    Poor water quality is one of the key environmental problems associated with shrimp and pangasius aquaculture in Vietnam. Several studies exist on the causes and effects of poor water quality, and on possible solutions for effluent control in these two economically important production systems. However, only a small number of Vietnamese farms apply these reduction options, raising questions over the state-enforced compliance with legislated water-quality measures. Voluntary standards and certi...

  6. Capacity building and services to assist local farmers to improve aquaculture management in Vietnam

    Lebailly, Philippe; Bui Thi, Nga; Ngo Thi Thu Hang; Tran Thi Nang, Thu

    2015-01-01

    Since 2000, we can observe important changes in traditional production systems of coastal communes in North Vietnam. Faced with relatively low incomes, rice farms converted the surfaces available to them in aquaculture ponds. These are difficult to reverse conversions were carried out by farmers seeking to improve family income in areas of relatively low rice productivity. These changes have had a significant impact on the revenues generated in coastal villages with changes in work organizati...

  7. I. Concepts of Highly Excited Electronic Systems / II. Electronic Correlation Mapping from Finite to Extended Systems

    Berakdar, Jamal

    2006-02-01

    Knowledge of the excitation characteristics of matter is decisive for the descriptions of a variety of dynamical processes, which are of significant technological interest. E.g. transport properties and the optical response are controlled by the excitation spectrum. This self-contained work is a coherent presentation of the quantum theory of correlated few-particle excitations in electronic systems. It begins with a compact resume of the quantum mechanics of single particle excitations. Particular emphasis is put on Green function methods, which offer a natural tool to unravel the relations between the physics of small and large electronic systems. The book contains explicit expressions for the Coulomb Green function of two charge particles and a generalization to three-body systems. Techniques for the many-body Green function of finite systems are introduced and some explicit calculations of the Green functions are given. Concrete examples are provided and the theories are contrasted with experimental data, when available. A complimentary volume presents an up-to-date selection of applications of the developed concepts and a comparison with available experiments is made

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

    Elwakil, S A [Theoretical Physics Group, Physics Department, Faculty of Science, Mansoura University, Mansoura (Egypt); Zahran, M A [Theoretical Physics Group, Physics Department, Faculty of Science, Mansoura University, Mansoura (Egypt); El-Shewy, E K [Theoretical Physics Group, Physics Department, Faculty of Science, Mansoura University, Mansoura (Egypt)

    2007-06-15

    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 {delta} on the nature of EASWs are discussed.

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

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

    2014-11-01

    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.

  10. Radiation Hard Electronics for Advanced Communication Systems Project

    National Aeronautics and Space Administration — Advanced reconfigurable/reprogrammable communication systems will require use of commercial sub 100 nm electronics. Legacy radiation tolerant circuits fail to...

  11. Electronic upgrade of the pneumatic Finnish system 'Rabbit'

    This paper describes the development of a new electronic module for control of the Finnish pneumatic system 'Rabbit', which usually use to send samples to RP-10 reactor core. The original analog electronic control is very old and replacement parts are very hard to obtain. Because of this, the system frequently was inoperative. A new electronic control system, fully digital, has been developed in the Electronic Development Laboratory of Huarangal Nuclear Center. This system is configurable, reliable and easier to use. Design details, operating considerations and its results are shown here. (orig.)

  12. National Electronic Injury Surveillance System (NEISS) On-line

    US Consumer Product Safety Commission — CPSC's National Electronic Injury Surveillance System (NEISS) is a national probability sample of hospitals. Patient information is collected for every emergency...

  13. Radiation Hard Electronics for Advanced Communication Systems Project

    National Aeronautics and Space Administration — Advanced reconfigurable/reprogrammable communication systems will require use of commercial sub 100 nm electronics. Legacy radiation tolerant circuits fail to...

  14. Hund's Rule in Two-Electron Atomic Systems

    Harriman, John E.

    2008-01-01

    A model proposed by Rioux to explain Hund's rule is investigated. Although the largest contribution to the singlet-triplet splitting in the two-electron atomic systems is the nuclear attraction term, this arises from different optimum scale factors in the two states and that difference is driven by the electron-electron exchange term. The…

  15. Highly Migratory Species Electronic Dealer Reporting System

    National Oceanic and Atmospheric Administration, Department of Commerce — Electronic dealer reporting for highly migratory species (HMS) dealers was instituted to expedite dealer reporting of federally-managed HMS, including swordfish,...

  16. Human Health Consequences of Use of Antimicrobial Agents in Aquaculture

    Heuer, Ole Eske; Kruse, H.; Grave, K.; Collignon, P.; Karunasagar, I.; Angulo, F.J.

    2009-01-01

    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...

  17. Impact of converison of mangrove ecosystem for aquaculture purposes

    Untawale, A; Wafar, S.

    in Indian mangroves. Conversion of mangroves for coconut and paddy cultivation alongwith setting of fish ponds is an age old practice in coastal India and is called as 'filtration' or 'trapping'. The brackish water aquaculture covers an area of 45...

  18. Integration of crustacean aquaculture with coastal rice farming in Vietnam

    Le Than Hung,

    1992-01-01

    Some examples are given of integration of crustacean aquaculture into coastal rice farming in Vietnam. Freshwater prawn (Macrobrachium rosenbergii ) and marine shrimp culture integrated with coastal rice farming and crab (Scylla serrata ) culture in backyard ponds and ricefields are described.

  19. Fishes of the Mekong River: conservation and need for aquaculture

    Nandeesha, M.C.

    1994-01-01

    Conservation and the potential and need for aquaculture of three major fish (Catlocarpio siamensis, Probarbus spp. and Pangasius gigas) of the Mekong River are discussed. Different steps being undertaken by the Cambodian government in doing such activities are highlighted.

  20. Proximate analyses - Utilization of Marine Process Waste for Aquaculture Feeds

    National Oceanic and Atmospheric Administration, Department of Commerce — Limited amounts of forage fish are available as an ingredient in feeds for the expanding aquaculture industry. Work is being conducted on a variety of underutilized...