WorldWideScience

Sample records for small scale production

  1. Adopting small-scale production of electricity

    Energy Technology Data Exchange (ETDEWEB)

    Tengvard, Maria; Palm, Jenny (Linkoeping Univ., Dept. of Technology and Social Change, Linkoeping (Sweden)). e-mail: maria.tengvard@liu.se

    2009-07-01

    In Sweden in 2008, a 'new' concept for small-scale electricity production attracted massive media attention. This was mainly due to the efforts of Swedish company Egen El, which is marketing small-scale photovoltaics (PVs) and wind turbines to households, both homeowners and tenants. Their main selling point is simplicity: their products are so easy to install that everyone can do it. Autumn 2008 also saw IKEA announce that within three years it would market solar panels. How, then, do households perceive these products? Why would households choose to buy them? How do households think about producing their own electricity? Analysis of material based on in-depth interviews with members of 20 households reveals that environmental concerns supply the main motive for adopting PVs or micro wind power generation. In some cases, the adopting households have an extensively ecological lifestyle and such adoption represents a way to take action in the energy area. For some, this investment is symbolic: a way of displaying environmental consciousness or setting an example to others. For still others, the adoption is a protest against 'the system' with its large dominant actors or is a way to become self-sufficient. These microgeneration installations are rejected mainly on economic grounds; other motives are respect for neighbours and difficulties finding a place to install a wind turbine.

  2. Productivity and production efficiency among small scale irrigated ...

    African Journals Online (AJOL)

    The study examined productivity and production efficiency among small scale irrigated sugarcane farmers in Niger State, Nigeria using a stochastic translog frontier function. Data for the study were obtained using structured questionnaires administered to 100 randomly selected sugarcane farmers from Paiko and Gurara ...

  3. Economic Analysis of Small Scale Fish Pond Production in Oguta ...

    African Journals Online (AJOL)

    What are the costs and returns of small-scale fishpond enterprises? What problems hinder the development of small-scale fishpond production? Data were collected with the aid of structured questionnaires and interviews. Descriptive statistics, gross margin and likert scale were employed in data analysis. Gross margin ...

  4. Development of small-scale peat production; Pienturvetuotannon kehittaeminen

    Energy Technology Data Exchange (ETDEWEB)

    Erkkilae, A.; Kallio, E. [VTT Energy, Jyvaeskylae (Finland)

    1997-12-01

    The aim of the project is to develop production conditions, methods and technology of small-scale peat production to such a level that the productivity is improved and competitivity maintained. The aim in 1996 was to survey the present status of small-scale peat production, and research and development needs and to prepare a development plan for small-scale peat production for a continued project in 1997 and for the longer term. A questionnaire was sent to producers by mail, and its results were completed by phone interviews. Response was obtained from 164 producers, i.e. from about 75 - 85 % of small-scale peat producers. The quantity of energy peat produced by these amounted to 3.3 TWh and that of other peat to 265 000 m{sup 3}. The total production of energy peat (large- scale producers Vapo Oy and Turveruukki Oy included) amounted to 25.0 TWh in 1996 in Finland, of which 91 % (22.8 TWh) was milled peat and 9 % (2.2 TWh) of sod peat. The total production of peat other than energy peat amounted to 1.4 million m{sup 3}. The proportion of small-scale peat production was 13 % of energy peat, 11 % of milled peat and 38 % of sod peat. The proportion of small-scale producers was 18 % of other peat production. The results deviate clearly from those obtained in a study of small-scale production in the 1980s. The amount of small-scale production is clearly larger than generally assessed. Small-scale production focuses more on milled peat than on sod peat. The work will be continued in 1997. Based on development needs appeared in the questionnaire, the aim is to reduce environmental impacts and runoff effluents from small- scale production, to increase the efficiency of peat deliveries and to reduce peat production costs by improving the service value of machines by increasing co-operative use. (orig.)

  5. Characteristics of small-scale palm oil production enterprise in ...

    African Journals Online (AJOL)

    The study examined characteristics of small-scale palm oil production enterprise in Anambra State, Nigeria. All the palm oil producers in Anambra State formed the population of the study. Multi-stage sampling technique was used to select 120 respondents for the study. Data were collected from primary source through ...

  6. Economic Analysis of Small Scale Egg Production in Gombe Local ...

    African Journals Online (AJOL)

    This study was conducted to determine the economic profitability of small-scale egg production in Gombe L.G.A. Gombe State. Data were collected from 36 famers using simple random sampling technique. The data collected were analyzed using descriptive statistics, gross margin and farm financial ratio analysis. The study ...

  7. Small scale studies of production of fissium aerosols

    International Nuclear Information System (INIS)

    Lindqvist, O.; Rydberg, J.

    1983-02-01

    A small scale study concerning the production and analysis of fission product aerosols formed at various temperatures as a function of the chemical composition of the fissium/corium mixture at the source is presented. CsOH, CsJ and Te are the main aerosol components to be expected. The thermodynamic characterization of occuring Te-iodides and other phases is of great importance for reactor core meltdown chemistry and for the evaluation of the aerosol transport tests. Elemental iodine seems not to be released in significant amounts in reducing atmosphere. Analysis data concerning elements, phases, themral analysis and gases are presented. (G.B.)

  8. Economic feasibility of small scale button mushroom production in pakistan

    International Nuclear Information System (INIS)

    Tahir, A.; Hassan, S.

    2013-01-01

    Abstract:- Mushroom is widely cultivated as a proteineous vegetable in many countries of the world including Pakistan. Its cultivation requires less space, care, equipment and cost compared to many other crops and livestock. The present study was conducted in 2010 to estimate the profitability of small scale button mushroom production at National Agricultural Research Centre (NARC) Islamabad, Pakistan. The cost of production methodology was used for this study. The yield and gross return of mushroom was estimated at 155.6 kg ha and Rs.77,800 ha , respectively. The results indicated the fact that mushroom production is very much remunerative to its producers as it can give maximum net return by reducing their cost of production as its cultivation is dependent on the agricultural raw material which is cheaply available. (author)

  9. Resource-Use Efficiency in Rice Production Under Small Scale ...

    African Journals Online (AJOL)

    acer

    specific objectives of the study were to determine resource use efficiency, describe ... economic level. ... this key variable with a view to stepping ... focused on small-scale irrigation systems for ... farmers were assumed to be operating under.

  10. Productive Efficiency of Small Scale Sawmilling Industries in Mufindi ...

    African Journals Online (AJOL)

    A structured questionnaire was used to collect data from 80 small-scale sawmills in Mufindi District. Data were analysed using descriptive as well as quantitative methods. Technical, scale and allocative efficiency score of sawmills were computed using data envelopment analysis programme developed by Coelli. Censored ...

  11. Resource-Use Efficiency in Rice Production Under Small Scale ...

    African Journals Online (AJOL)

    This was attested by the high ratios (greater than unity) of MVP/MFC of all the variables. For optimum resource allocation to fertilizer, labour and land about 85.7%, 83.3% and 69% increase in MVP is required respectively. The estimated elasticity of production summed up to 0.815 meaning decreasing return to scale.

  12. Process improvement of knives production in a small scale industry

    Science.gov (United States)

    Ananto, Gamawan; Muktasim, Irfan

    2017-06-01

    Small scale industry that produces several kinds of knive should increase its capacity due to the demand from the market. Qualitatively, this case study consisted of formulating the problems, collecting and analyzing the necessary data, and determining the possible recommendations for the improvement. While the current capacity is only 9 (nine), it is expected that 20 units of knife will produced per month. The processes sequence are: profiling (a), truing (b), beveling (c), heat treatment (d), polishing (e), assembly (f), sharpening (g) and finishing (h). The first process (a) is held by out-house vendor company while other steps from (b) to (g) are executed by in-house vendor. However, there is a high dependency upon the high skilled operator who executes the in -house processes that are mostly held manually with several unbalance successive tasks, where the processing time of one or two tasks require longer duration than others since the operation is merely relied on the operator's skill. The idea is the improvement or change of the profiling and beveling process. Due to the poor surface quality and suboptimal hardness resulted from the laser cut machine for profiling, it is considered to subst itute this kind of process with wire cut that is capable to obtain good surface quality with certain range levels of roughness. Through simple cutting experiments on the samples, it is expected that the generated surface quality is adequate to omit the truing process (b). In addition, the cutting experiments on one, two, and four test samples resulted the shortest time that was obtained through four pieces in one cut. The technical parameters were set according to the recommendation of machine standard as referred to samples condition such as thickness and path length that affect ed the rate of wear. Meanwhile, in order to guarantee the uniformity of knife angles that are formed through beveling process (c), a grinding fixture was created. This kind of tool diminishes the

  13. Resource Use Productivity Among Small-Scale Farmers In Yola ...

    African Journals Online (AJOL)

    The findings of the study revealed that characteristics of the farmers such as age, level of education, farm size, sources of farm labour and of farm finance do not have significant relationship with resource use productivity. However, net annual income from farming was found to have a significant relationship with resource ...

  14. Economic Analysis Of Small Scale Poultry Production In Zaria ...

    African Journals Online (AJOL)

    Data collected was analyzed using descriptive statistics, farm budgeting analysis, production and profit functions. Fixed and variable costs were estimated and deducted from gross returns to give net cash returns. The major investment includes cost of day old chicks and feeding. Feeding constitute the highest, accounting for ...

  15. Energy harvesting: small scale energy production from ambient sources

    Science.gov (United States)

    Yeatman, Eric M.

    2009-03-01

    Energy harvesting - the collection of otherwise unexploited energy in the local environment - is attracting increasing attention for the powering of electronic devices. While the power levels that can be reached are typically modest (microwatts to milliwatts), the key motivation is to avoid the need for battery replacement or recharging in portable or inaccessible devices. Wireless sensor networks are a particularly important application: the availability of essentially maintenance free sensor nodes, as enabled by energy harvesting, will greatly increase the feasibility of large scale networks, in the paradigm often known as pervasive sensing. Such pervasive sensing networks, used to monitor buildings, structures, outdoor environments or the human body, offer significant benefits for large scale energy efficiency, health and safety, and many other areas. Sources of energy for harvesting include light, temperature differences, and ambient motion, and a wide range of miniature energy harvesters based on these sources have been proposed or demonstrated. This paper reviews the principles and practice in miniature energy harvesters, and discusses trends, suitable applications, and possible future developments.

  16. Cost analysis of enzymatic biodiesel production in small-scaled packed-bed reactors

    NARCIS (Netherlands)

    Budzaki, S.; Miljic, G.; Sundaram, S.; Tisma, M.; Hessel, V.

    2017-01-01

    A cost analysis of enzymatic biodiesel production in small-scaled packed-bed reactors using refined sunflower oil is performed in this work. A few enzymatic micro-flow reactors have so far reached a performance close to gram-scale, which might be sufficient for the pharmaceutical industry. This

  17. Assessment of Small-scale Buffalo Milk Dairy Production-A Premise for a Durable Development

    Directory of Open Access Journals (Sweden)

    Marian MIHAIU

    2012-05-01

    Full Text Available Buffalo husbandry is an important source of income for a number of small-scale producers in Romania that is why an assessment of its products quality is much needed for improvement and evaluation of their vulnerability to international competition. In order to ascertain possible developments in the buffalo dairy sector and to broadly identify areas of intervention that favor small-scale dairy producers, the study examined the potential to improve buffalo milk production by evaluating its authenticity and hygienic quality. The methods used involved the molecular testing (PCR-technique for identifying cow, sheep or goat DNA in the dairy products samples collected from the small-scale producers market. The hygienic quality of these samples was determined through classical microbiology methods, highly developed techniques (Trek System and PCR for bacterial species confirmation. The results showed that a high percent (65%, from the products found were adulterated with other species milk, mostly cow milk. The most commonly falsified buffalo dairy products were the cheese and the traditional product telemea. The prevalence of the bacterial species identified belonged to Listeria innocua and Listeria welshmeri. The conclusion of this study is the need of a durable development system in this particular dairy chain to improve and assure the authenticity and quality of the small-scale producers products and their reliability for the consumers.

  18. The Role of Small-Scale Biofuel Production in Brazil: Lessons for Developing Countries

    Directory of Open Access Journals (Sweden)

    Arielle Muniz Kubota

    2017-07-01

    Full Text Available Small-scale biofuel initiatives to produce sugarcane ethanol are claimed to be a sustainable opportunity for ethanol supply, particularly for regions with price-restricted or no access to modern biofuels, such as communities located far from the large ethanol production centers in Brazil and family-farm communities in Sub-Saharan Africa, respectively. However, smallholders often struggle to achieve economic sustainability with ethanol microdistilleries. The aim of this paper is to provide an assessment of the challenges faced by small-scale bioenergy initiatives and discuss the conditions that would potentially make these initiatives economically feasible. Ethanol microdistilleries were assessed through a critical discussion of existent models and through an economic analysis of different sugarcane ethanol production models. The technical-economic analysis showed that the lack of competitiveness against large-scale ethanol distillery, largely due to both low crop productivity and process efficiency, makes it unlikely that small-scale distilleries can compete in the national/international ethanol market without governmental policies and subsidies. Nevertheless, small-scale projects intended for local supply and integrated food–fuel systems seem to be an interesting alternative that can potentially make ethanol production in small farms viable as well as increase food security and project sustainability particularly for local communities in developing countries.

  19. Small-scale production and utilization of wood fuels; Puupolttoaineen pientuotanto ja -kaeyttoe - katsaus tutkimus- projekteihin

    Energy Technology Data Exchange (ETDEWEB)

    Tuomi, S. [Work Efficiency Inst., Rajamaeki (Finland)

    1996-12-31

    The objective of the research on small-scale production of wood fuels was to promote the forest owners` own utilization and procurement of firewood. The profitability of firewood was improved by developing new farm-tractor mountable equipment and methods for forest owners and small-entrepreneurs for harvesting of first-thinning wood and other small-dimeter wood. Totally new solution for machine felling of small trees and chopwood production were developed to serial production level. Recyclable processing and delivery units were developed for delivery of chopwood. A calculation model for analysing the costs of small-scale production of firewood became ready. A guide on the development of heating-entrepreneur activities, serving the entrepreneurs, was published. The objective of the firewood utilization research was to reduce the technical barriers of the utilization of firewood in small-house and real-estate scales. The main aim was to reduce the flue-gas emissions. The emissions of the fireplaces were reduced by developing the construction of fireplaces, catalytic combustion and heating methods. An automatic stoker-burner was developed for real-estate scale and a boiler series was designed for biofuels

  20. Small-scale production and utilization of wood fuels; Puupolttoaineen pientuotanto ja -kaeyttoe - katsaus tutkimus- projekteihin

    Energy Technology Data Exchange (ETDEWEB)

    Tuomi, S [Work Efficiency Inst., Rajamaeki (Finland)

    1997-12-31

    The objective of the research on small-scale production of wood fuels was to promote the forest owners` own utilization and procurement of firewood. The profitability of firewood was improved by developing new farm-tractor mountable equipment and methods for forest owners and small-entrepreneurs for harvesting of first-thinning wood and other small-dimeter wood. Totally new solution for machine felling of small trees and chopwood production were developed to serial production level. Recyclable processing and delivery units were developed for delivery of chopwood. A calculation model for analysing the costs of small-scale production of firewood became ready. A guide on the development of heating-entrepreneur activities, serving the entrepreneurs, was published. The objective of the firewood utilization research was to reduce the technical barriers of the utilization of firewood in small-house and real-estate scales. The main aim was to reduce the flue-gas emissions. The emissions of the fireplaces were reduced by developing the construction of fireplaces, catalytic combustion and heating methods. An automatic stoker-burner was developed for real-estate scale and a boiler series was designed for biofuels

  1. Assessment of Small-scale Buffalo Milk Dairy Production-A Premise for a Durable Development

    Directory of Open Access Journals (Sweden)

    Marian MIHAIU

    2012-05-01

    Full Text Available Buffalo husbandry is an important source of income for a number of small-scale producers in Romania that is why an assessment of its� product�s quality is much needed for improvement and evaluation of their vulnerability to international competition. In order to ascertain possible developments in the buffalo dairy sector and to broadly identify areas of intervention that favor small-scale dairy producers, the study examined the potential to improve buffalo milk production by evaluating its authenticity and hygienic quality. The methods used involved the molecular testing (PCR-technique for identifying cow, sheep or goat DNA in the dairy products� samples collected from the small-scale producers market. The hygienic quality of these samples was determined through classical microbiology methods, highly developed techniques (Trek System and PCR for bacterial species confirmation. The results showed that a high percent (65%, from the products found were adulterated with other species milk, mostly cow milk. The most commonly falsified buffalo dairy products were the cheese and the traditional product �telemea�. The prevalence of the bacterial species identified belonged to Listeria innocua and Listeria welshmeri. The conclusion of this study is the need of a durable development system in this particular dairy chain to improve and assure the authenticity and quality of the small-scale producers� products and their reliability for the consumers.

  2. analysis of cost efficiency in food crop production among small-scale

    African Journals Online (AJOL)

    PROF. BARTH EKWEME

    Food crop production in Nigeria is dominated by small-scale farmers ... influenced by farm-specific factors, which delineate their ..... vii). Cost of seed: This is the total expenses on seed incurred by the farmer during the last cropping season. It.

  3. Could small scale vegetable production contribute to a green economy in South Africa?

    CSIR Research Space (South Africa)

    Musvoto, Constansia D

    2015-02-01

    Full Text Available and produces for sale. Some of the practices on these farms are compatible with a green economy, and with interventions that improve alignment with green economy principles, small scale vegetable production could contribute to a green economy and open up...

  4. Productivity, Efficiency, and Competitiveness of Small-Scale Organic Cotton Production in Tanzania

    DEFF Research Database (Denmark)

    Mgeni, Dotto; Henningsen, Arne

    cannot be adjusted in the short run. However, land, labor, and organic fertilizer can neither be traded on a perfect market nor are their quantities completely fixed for cotton production, but these input quantities can be adjusted by adjusting their use for other activities of the household. Hence......Cotton is known as the “white gold” of Africa since it is the only export crop in which the continent’s share in the world market has increased over the past decades. Total cotton production as well as productivity grew particularly in Western and Central Africa. In contrast, cotton production grew...... and output, as well as socio-economic and agronomic factors, but also on the shadow prices of all sparsely traded inputs, i.e. land, labor, and organic fertilizer. Hence, we can not only analyze productivity, technical efficiency, and scale efficiency, but also allocative efficiency, profitability...

  5. Fuel from farms: a guide to small-scale ethanol production

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-02-01

    A guide on fermentation processes with emphasis on small-scale production of ethanol using farm crops as a source of raw material is published. The current status of on-farm ethanol production as well as an overview of some of the technical and economic factors is presented. Decision and planning worksheets and a sample business plan for use in decision making are included. Specifics in production including information on the raw materials, system components, and operational requirements are also provided. Diagrams of fermentors and distilling apparatus are included. (DC)

  6. Small-scale production and use of wood fuels. Report of the year 2005

    International Nuclear Information System (INIS)

    Alakangas, E.

    2005-01-01

    The target areas of the research programme are: Small-scale production and handling of wood fuels, Pellet production, distribution and use, Heating technology and Business and service concepts. Production and processing technology focuses on cost-effectiveness, fuel quality, logistics of production chains and storage, transport and feeding solutions. The quality of pellets in the view of the whole chain: production, storage, distribution and feeding, is under scrutiny. In addition, storage and distribution systems are being developed. The aim is to create functional and comprehensive heat production systems based on the use of wood pellets. Emissions from small-scale use are reduced and efficiency of combustion improved to meet the Central European standard. Modern control, automation and data management systems are applied cost-effectively. The aim is to create comprehensive systems and modular solutions. Business and service concepts relate to all target areas such as heat entrepreneurship and energy service companies (ESCO). The aim is to promote the networking of companies and develop new solutions for fuel and heat production services

  7. Climate change impacts and adaptations on small-scale livestock production

    Directory of Open Access Journals (Sweden)

    Taruvinga, A.

    2013-06-01

    Full Text Available The paper estimated the impacts of climate change and adaptations on small-scale livestock production. The study is based on a survey of 1484 small-scale livestock rural farmers across the Eastern Cape Province of South Africa. Regression estimates finds that with warming, the probability of choosing the following species increases; goats, dual purpose chicken (DPC, layers, donkeys and ducks. High precipitation increases the probability of choosing the following animals; beef, goats, DPC and donkeys. Further, socio-economic estimates indicate that livestock selection choices are also conditioned by gender, age, marital status, education and household size. The paper therefore concluded that as climate changes, rural farmers switch their livestock combinations as a coping strategy. Unfortunately, rural farmers face a limited preferred livestock selection pool that is combatable to harsh climate which might translate to a bleak future for rural livestock farmers.

  8. Novel Production Protocol for Small-scale Manufacture of Probiotic Fermented Foods

    Science.gov (United States)

    Westerik, Nieke; Wacoo, Alex Paul; Sybesma, Wilbert; Kort, Remco

    2016-01-01

    A novel dried bacterial consortium of Lactobacillus rhamnosus yoba 2012 and Streptococcus thermophilus C106 is cultured in 1 L of milk. This fresh starter can be used for the production of fermented milk and other fermented foods either at home or at small-scale in rural settings. For the fresh starter, 1 L of milk is pasteurized in a pan that fits into a larger pan containing water, placed on a source of heat. In this water bath, the milk is heated and incubated at 85 °C for 30 min. Thereafter, the milk is cooled down to 45 °C, transferred to a vacuum flask, inoculated with the dried bacteria and left for at least 16 hr between 30 °C and 45 °C. For the purpose of frequent home production, the fresh starter is frozen into ice cubes, which can be used for the production of small volumes of up to 2 L of fermented milk. For the purpose of small-scale production in resource-poor countries, pasteurization of up to 100 L of milk is conducted in milk cans that are placed in a large sauce pan filled with water and heated on a fire at 85 °C for 30 min, and subsequently cooled to 45 °C. Next, the 100 L batch is inoculated with the 1 L freshly prepared starter mentioned before. To assure an effective fermentation at a temperature between 30 and 45 °C, the milk can is covered with a blanket for 12 hr. For the production of non-dairy fermented foods, the fresh starter is left in a cheese cloth for 12 hr, and the drained-off whey can be subsequently used for the inoculation of a wide range of food raw materials, including vegetables and cereal-based foods. PMID:27684196

  9. Qualification of academic facilities for small-scale automated manufacture of autologous cell-based products.

    Science.gov (United States)

    Hourd, Paul; Chandra, Amit; Alvey, David; Ginty, Patrick; McCall, Mark; Ratcliffe, Elizabeth; Rayment, Erin; Williams, David J

    2014-01-01

    Academic centers, hospitals and small companies, as typical development settings for UK regenerative medicine assets, are significant contributors to the development of autologous cell-based therapies. Often lacking the appropriate funding, quality assurance heritage or specialist regulatory expertise, qualifying aseptic cell processing facilities for GMP compliance is a significant challenge. The qualification of a new Cell Therapy Manufacturing Facility with automated processing capability, the first of its kind in a UK academic setting, provides a unique demonstrator for the qualification of small-scale, automated facilities for GMP-compliant manufacture of autologous cell-based products in these settings. This paper shares our experiences in qualifying the Cell Therapy Manufacturing Facility, focusing on our approach to streamlining the qualification effort, the challenges, project delays and inefficiencies we encountered, and the subsequent lessons learned.

  10. A versatile, steam reforming based small-scale hydrogen production process

    International Nuclear Information System (INIS)

    P C Hulteberg; F A Silversand; B Porter; R Woods

    2006-01-01

    In this paper, a new design methodology and process is proposed for small scale pure hydrogen production capable of serving energy markets ranging from distributed generation to vehicular refuelling. The system was designed for producing 7 Nm 3 /hr pure hydrogen (purity of ≤ 1 ppm CO dry), yielding 10 kWe net power from a fuel cell system with an overall parasitic power loss ≤ 10 %. The discussion of this process includes a detailed description of the design methodology and operational results of the catalytic converter, the hydrogen purification system and the fuel cell system. This paper will discuss the design methodology of the overall system, as well as the specific design of the catalytic converter, the catalysts used within, and the hydrogen purification system. It will also report the system performance including gas purity, recovery rate, overall hydrogen production efficiencies, and electrical efficiencies during fuel cell operation. (authors)

  11. Resource use efficiency in small-scale rice production in Nigeria ...

    African Journals Online (AJOL)

    The production function for rice, elasticity of production, return to scale, marginal productivity and level of efficiency of inputs used in rice production were determined. ... With the exception of fertilizer that was over-utilized, all other inputs were underutilized with ratios of marginal value products to unit prices greater than unity ...

  12. Assessing the Sustainability of Different Small-Scale Livestock Production Systems in the Afar Region, Ethiopia

    Directory of Open Access Journals (Sweden)

    Ngufor L. Atanga

    2013-12-01

    Full Text Available Livestock production is a key income source in eastern Africa, and 80% of the total agricultural land is used for livestock herding. Hence, ecological and socio-economically sustainable rangeland management is crucial. Our study aimed at selecting operational economic, environmental and social sustainability indicators for three main pastoral (P, agro-pastoral (AP, and landless intensive (LI small scale livestock production systems for use in sustainability assessment in Ethiopia. Quantitative and qualitative data were collected through grey literature and semi-structured interviews, assessing livestock and feed resources, production technology, land tenure, financial and gender issues. Our results suggested that feed shortages (FS are directly related to grazing pressure (G and inversely related to grass recovery rates (R. According to our indicators, AP was the most sustainable while P and LI were only conditionally sustainable production systems. 93% of 82 interviewees claimed that private land ownership was the best land tenure incentive for efficient rangeland management. Farmers perceived Prosopis juliflora expansion, sporadic rainfall, and disease infestation as the most significant causes for decreasing livestock productivity. Landless intensive farmers had the highest equality in income distribution (Gini Index: GI = 0.4, followed by P and AP (each with a GI = 0.5. Neither educational background nor income seemed to determine grazing species conservation efforts. We claimed that sustainability indicators are valuable tools to highlight shortcomings and strengths of the three main livestock production systems and help with future livestock management in Ethiopia. Selecting suitable indicators, however, is crucial as data requirements and availability can vary across livestock systems.

  13. Scaling Up Small Millet Post-Harvest and Nutritious Food Products ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Technology solutions to improve processing Processing millets for modern food ... Small scale, large impact By the end of the project, two new business models will be ... The Royal Institution for the Advancement of Learning/McGill University.

  14. Occurrence of Staphylococcus aureus on Farms with Small Scale Production of Raw Milk Cheeses in Poland

    Directory of Open Access Journals (Sweden)

    Jolanta G. Rola

    2016-03-01

    Full Text Available This paper describes the results of a 3-year study on the prevalence, enterotoxinogenicity and resistance to antimicrobials of S. aureus isolated on dairy farms with small scale production of raw cow milk cheeses. The samples of raw milk, semi-finished products and the final products as well as swabs were collected between 2011 and 2013 from nine dairy farms in Poland. A total of 244 samples were examined, of which 122 (50.0% were contaminated with S. aureus including 18 of 26 (69.2% mature cheese samples with log10 CFU g−1 between <1- and 7.41. In swabs collected from the staff and production environment the highest contamination rate with coagulase positive staphylococci (CPS was detected on hands of cheese makers (4.34 log10 CFU/swab. None of the cheese samples contaminated with CPS contained staphylococcal enterotoxins (SEs. However, 55 of 122 (45.1% S. aureus isolates possessed SEs genes, mainly (26 of 55; 47.3% a combination of the sed, sej and ser genes. Furthermore, the sep (15 of 55; 27.3% as well as seg and sei (9 of 55; 16.4% genes were also identified. The remaining S. aureus isolates possessed the sea gene (one isolate, the combination of sec, seg and sei (three isolates as well as the sed, sej, sep and ser markers together (one CPS. Resistance to penicillin (62 of 122 isolates; 50.8% was the most common among the tested isolates. Some CPS were also resistant to chloramphenicol (7; 5.7% and tetracycline (5; 4.1%. The obtained results indicated that the analyzed cheeses were safe for consumers. To improve the microbiological quality of traditional cheese products more attention should be paid to animal welfare and hygiene practices during the process of cheese manufacturing in some dairy farms.

  15. Assessment of welfare and egg production of laying hens moravia ssl in small-scale breeding

    Directory of Open Access Journals (Sweden)

    Mária Angelovičová

    2015-10-01

    Full Text Available The purpose of this study was to investigate the welfare of laying hens Moravia SSL housed in small-scale hen house with free range, behavior, egg production and selected physical indicators of eggs and chemical indicators of egg mass. The laying hens were kept in a hen house on deep litter. Breeding facility of hen house was within the meaning of recommendation for applying the principles of welfare, i.e. the space and breeding facility within the meaning of enriched breeding environment. Stocking density of the laying hens corresponded with recommendations for unrestricted movement and implementing natural activities. The hen house was equipped with the perch, nest, feeder and drinker. The commercial feed mixture was used for feeding, which is intended for laying hens. The kitchen remains were added to feed mixture, as are wet bread, the non-edible remains of foodstuffs. A feed mixture was served to laying hens 825 g per day. The laying hens had free access to drinking water, grazing, ground pecking, ground scratching and dust-bathing and in the free range. We focused investigation of on the egg laying intensity, selected parameters of physical egg quality and chemical egg contents. Time to relax of laying hens was adjusted according to the summer and winter breeding seasons. The main activities of free-range hens are grazing, ground pecking, ground scratching and dust-bathing. The main activities of free-range hens are grazing, ground pecking, ground scratching and dust-bathing. These activities were investigated in laying hens too in dependent of year period, more in the summer. Housing of the hens was equipped with the perch. The laying hens regularly used a perch. A beginning of occupation the perch was at the time of time growing dark, at the end of the light day. A nesting material was selected regular, monthly exchange. It was meadow hay of excellent quality for the collection of high quality and safe eggs from nests in the hen house

  16. Life cycle assessment of small-scale high-input Jatropha biodiesel production in India

    International Nuclear Information System (INIS)

    Pandey, Krishan K.; Pragya, Namita; Sahoo, P.K.

    2011-01-01

    Highlights: → NEB and NER of high input Jatropha biodiesel system was higher than those of low input. → These values further increase on including the energy content of the co-products, and in the further years. → Maximum energy use was during oil extraction, followed by oil processing and fertilizer use. → Allocation of resources at right time and with proper care increase the overall system productivity. -- Abstract: In the current scenario of depleting energy resources, increasing food insecurity and global warming, Jatropha has emerged as a promising energy crop for India. The aim of this study is to examine the life cycle energy balance for Jatropha biodiesel production and greenhouse gas emissions from post-energy use and end combustion of biodiesel, over a period of 5 years. It's a case specific study for a small scale, high input Jatropha biodiesel system. Most of the existing studies have considered low input Jatropha biodiesel system and have used NEB (Net energy balance i.e. difference of energy output and energy input) and NER (Net energy ratio i.e. ratio of energy output to energy input) as indicators for estimating the viability of the systems. Although, many of them have shown these indicators to be positive, yet the values are very less. The results of this study, when compared with two previous studies of Jatropha, show that the values for these indicators can be increased to a much greater extent, if we use a high input Jatropha biodiesel system. Further, when compared to a study done on palm oil and Coconut oil, it was found even if the NEB and NER of biodiesel from Jatropha were lesser in comparison to those of Palm oil and Coconut oil, yet, when energy content of the co-products were also considered, Jatropha had the highest value for both the indicators in comparison to the rest two.

  17. Impact of improved technologies on small-scale soybean production: empirical evidence from benue state, nigeria

    International Nuclear Information System (INIS)

    Adisa, R.S.; Balogun, K.S.

    2013-01-01

    The study examined the impact of improved technologies on the lives of small-scale soybean farmers in Benue State, Nigeria. A total of 160 respondents were selected using simple random sampling technique. Data were analyzed using descriptive statistics, Tobit model and the Kruskal-Wallis test. Findings revealed that 35.6% of the respondents were between 31 and 40 years old, 40.6% had household size of between 6 and 10 members. Majority of the respondents were male, married, and had secondary school education. Tobit analysis revealed that farmers socioeconomic characteristics which include gender, educational status and farming experience; and farmers knowledge on soybean innovations were significant factors determining the adoption of improved soybean production technologies. These factors were statistically significant at p=0.05. The adoption of improved soybean technologies has had a clear positive impact on farmers belief on soybean innovations. The major problems facing farmers in the adoption of improved soybean production technologies according to Kruskal-Wallis ranking were high cost of inputs, problem of labour availability and lack of credit/loan. The results of this study provide a strong case for the promotion of soybean as a solution for malnutrition and a means of poverty alleviation for poor people. (author)

  18. Economic Appraisal of Small and Medium Scale Poultry Egg Production in Ife and Ilesha Metropolis, Osun State, Nigeria.

    Directory of Open Access Journals (Sweden)

    Busari Ahmed Olugbenga

    2015-06-01

    Full Text Available The study appraised the economic performance of small and medium scale poultry egg production in Ife and Ilesha metropolis, Osun State Nigeria. A purposive sampling was used to select one hundred and twenty poultry egg farmers, cluster sampling was used to select areas where small and medium scale were concentrated in the study area then sixty (60 small scale and sixty (60 medium scale were randomly selected to form the population of the study. Data were collected through structured interview schedule. Descriptive statistics such as means and percentages were employed for budgetary analysis and economic performance. The ordinary least square was used to determine the significant variables influencing the gross margin of poultry egg farmers at different levels of scale of production. The study shows that the gross margin of small farms was ₦575.65 while the gross margin of medium farms was ₦43672.62. The total production cost of small and medium farms were ₦1480.25 and ₦29654.43 respectively. The results further reveal that costs of feed constituted the largest share of the total costs for the two categories of farm size. The amount spent on drug and feed were the only significant determining factors of revenue accruable to both categories of poultry egg farmers. Although, poultry egg production was profitable in the study area, the level of profit depended on the scale of operation.

  19. Small scale optics

    CERN Document Server

    Yupapin, Preecha

    2013-01-01

    The behavior of light in small scale optics or nano/micro optical devices has shown promising results, which can be used for basic and applied research, especially in nanoelectronics. Small Scale Optics presents the use of optical nonlinear behaviors for spins, antennae, and whispering gallery modes within micro/nano devices and circuits, which can be used in many applications. This book proposes a new design for a small scale optical device-a microring resonator device. Most chapters are based on the proposed device, which uses a configuration know as a PANDA ring resonator. Analytical and nu

  20. Progress towards a small-scale, automated optical thin-film production capability

    International Nuclear Information System (INIS)

    Drage, D.J.; Netterfield, R.P.; Dligatch, S.; Blenman, N.; Fairman, P.S.; Katsaros, A.; Preston, E.W.

    2000-01-01

    Full text: The Optical Thin-film group at CSIRO Telecommunications and Industrial Physics (CTIP) has, working over a number of years, built up considerable expertise in producing complex dielectric, multilayer thin-film designs to meet unusual and demanding optical performance specifications. At the same time the process of vacuum deposition of dielectric materials has been advanced, particularly by the development and use of ion-assisted deposition (IAD). Proposed modifications to our existing chamber (DB600) and the addition of a new, larger diameter chamber (DD750), presently under construction, will increase output and reliability while improving quality. We will describe the changes already made to the DB600 such as: the gridless ion source, in-situ ellipsometric monitoring along with spectrophotometric monitoring, full e-beam scan on the material source, complete source shuttering and reactive deposition of SiO 2 from thermally evaporated SiO. The effects of making these beneficial changes will be described. Further changes to be made to the DB600 include, replacing its diffusion pump with a cryo-pump and automatic control of the deposition process. All the changes described for the DB600 along with a positive drive system for rotation of the substrate holder, rod feed e-gun hearths, and multiple crystal monitor heads, will be included in the DD750 design which will also be described. We believe that these improvements will give us the capability of small-scale production of reproducible, high quality filters

  1. Incidence of Listeria monocytogenes and Listeria spp. in a small-scale mushroom production facility.

    Science.gov (United States)

    Viswanath, Prema; Murugesan, Latha; Knabel, Stephen J; Verghese, Bindhu; Chikthimmah, Naveen; Laborde, Luke F

    2013-04-01

    Listeria monocytogenes is a foodborne pathogen of significant concern to the agricultural and food processing industry because of its ability to grow and persist in cool and moist environments and its association with listeriosis, a disease with a very high mortality rate. Although there have been no listeriosis outbreaks attributed to fresh mushrooms in the United States, retail surveys and recalls are evidence that L. monocytogenes contamination of mushrooms (Agaricus bisporus) can occur. The objective of this study was to determine the prevalence of Listeria spp., including L. monocytogenes, in a small-scale mushroom production facility on the campus of the Pennsylvania State University in the United States. Of 184 samples taken from five production zones within the facility, 29 (15.8%) samples were positive for Listeria spp. Among the Listeria spp. isolates, L. innocua was most prevalent (10.3%) followed by L. welshimeri (3.3%), L. monocytogenes (1.6%), and L. grayi (0.5%). L. monocytogenes was recovered only from the phase I raw material composting area. Isolates of L. monocytogenes were confirmed and serotyped by multiplex PCR. The epidemiological relatedness of the three L. monocytogenes isolates to those serotypes or lineages frequently encountered in listeriosis infections was determined by multi-virulence-locus sequence typing using six virulence genes, namely, prfA, inlB, inlC, dal, clpP, and lisR. The phylogenetic positions of the three isolates in the dendrogram prepared with data from other isolates of L. monocytogenes showed that all isolates were grouped with serotype 4a, lineage IIIA. To date, this serotype has rarely been reported in foodborne disease outbreaks.

  2. A small-scale flow alkaline fuel cell for on-site production of hydrogen peroxide

    International Nuclear Information System (INIS)

    Brillas, Enric; Alcaide, Francisco; Cabot, Pere-Lluis

    2002-01-01

    The behavior of a small-scale flow alkaline fuel cell (AFC) built-up for on-site production of HO 2 - using commercial gas-diffusion electrodes has been studied. It produces a spontaneous current due to the oxidation of H 2 to H 2 O at the H 2 -diffusion anode and the reduction of O 2 to HO 2 - at the O 2 -diffusion cathode, while a fresh 1.0-6.0 mol dm -3 KOH electrolyte at 15.0-45.0 deg. C is injected through it. Under circulation of HO 2 - +KOH solutions in open circuit, the flow AFC behaves as a two-electron reversible system. When it is shorted with an external load (R ext ), steady cell voltage-current density curves are found. The use of O 2 /N 2 mixtures to fed the cathode causes a loss of its performance, being required to supply pure O 2 to yield a maximum HO 2 - electrogeneration. The current density and HO 2 - productivity increase with raising OH - concentration, temperature and pressure of O 2 fed. At R ext =0.10 Ω, a current efficiency close to 100% is obtained, and current densities >100 mA cm -2 are achieved for 1.0 mol dm -3 KOH at 45.0 deg. C and for higher KOH concentrations at 25.0 deg. C. The flow AFC can work under optimum conditions up to 6.0 mol dm -3 KOH and 45.0 deg. C for possible industrial applications

  3. Catalytic heat exchangers for small-scale production of hydrogen - feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Silversand, F [Catator AB, Lund (Sweden)

    2002-02-01

    A feasibility study concerning heat-exchanger reactors in small-scale production of hydrogen has been performed on the request of Svenskt Gastekniskt Center AB and SWEP International AB. The basic idea is to implement different catalysts into brazed plate-type heat exchangers. This can be achieved by installing catalytic cylinders in the inlet-and outlet ports of the heat exchangers or through treatment of the plates to render them catalytically active. It is also possible to sandwich catalytically active wire meshes between the plates. Experiments concerning steam reforming of methanol and methane have been performed in a micro-reactor to gather kinetic data for modelling purposes. Performance calculations concerning heat exchanger reactors have then been conducted with Catator's generic simulation code for catalytic reactors (CatalystExplorer). The simulations clearly demonstrate the technical performance of these reactors. Indeed, the production rate of hydrogen is expected to be about 10 nm{sup 3}/h per litre of heat exchanger. The corresponding value for a conventional steam-reforming unit is about 1 nm{sup 3}/h or less per litre of reactor volume. Also, the compactness and the high degree of integration together with the possibilities of mass production will give an attractive cost for such units. Depending on the demands concerning the purity of the hydrogen it is possible to add secondary catalytic steps like water-gas shifters, methanation and selective oxidation, into a one-train unit, i.e. to design an all-inclusive design. Such reactors can be used for the supply of hydrogen to fuel cells. The production cost for hydrogen can be cut by 60 - 70% through the utilisation of heat exchanger reactors instead of conventional electrolysis. This result is primarily a result of the high price for electricity compared to the feed stock prices in steam reforming. It is important to verify the performance calculations and the simulation results through experimental

  4. Catalytic heat exchangers for small-scale production of hydrogen - feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Silversand, F. [Catator AB, Lund (Sweden)

    2002-02-01

    A feasibility study concerning heat-exchanger reactors in small-scale production of hydrogen has been performed on the request of Svenskt Gastekniskt Center AB and SWEP International AB. The basic idea is to implement different catalysts into brazed plate-type heat exchangers. This can be achieved by installing catalytic cylinders in the inlet-and outlet ports of the heat exchangers or through treatment of the plates to render them catalytically active. It is also possible to sandwich catalytically active wire meshes between the plates. Experiments concerning steam reforming of methanol and methane have been performed in a micro-reactor to gather kinetic data for modelling purposes. Performance calculations concerning heat exchanger reactors have then been conducted with Catator's generic simulation code for catalytic reactors (CatalystExplorer). The simulations clearly demonstrate the technical performance of these reactors. Indeed, the production rate of hydrogen is expected to be about 10 nm{sup 3}/h per litre of heat exchanger. The corresponding value for a conventional steam-reforming unit is about 1 nm{sup 3}/h or less per litre of reactor volume. Also, the compactness and the high degree of integration together with the possibilities of mass production will give an attractive cost for such units. Depending on the demands concerning the purity of the hydrogen it is possible to add secondary catalytic steps like water-gas shifters, methanation and selective oxidation, into a one-train unit, i.e. to design an all-inclusive design. Such reactors can be used for the supply of hydrogen to fuel cells. The production cost for hydrogen can be cut by 60 - 70% through the utilisation of heat exchanger reactors instead of conventional electrolysis. This result is primarily a result of the high price for electricity compared to the feed stock prices in steam reforming. It is important to verify the performance calculations and the simulation results through

  5. Planimetric Features Generalization for the Production of Small-Scale Map by Using Base Maps and the Existing Algorithms

    Directory of Open Access Journals (Sweden)

    M. Modiri

    2014-10-01

    Full Text Available Cartographic maps are representations of the Earth upon a flat surface in the smaller scale than it’s true. Large scale maps cover relatively small regions in great detail and small scale maps cover large regions such as nations, continents and the whole globe. Logical connection between the features and scale map must be maintained by changing the scale and it is important to recognize that even the most accurate maps sacrifice a certain amount of accuracy in scale to deliver a greater visual usefulness to its user. Cartographic generalization, or map generalization, is the method whereby information is selected and represented on a map in a way that adapts to the scale of the display medium of the map, not necessarily preserving all intricate geographical or other cartographic details. Due to the problems facing small-scale map production process and the need to spend time and money for surveying, today’s generalization is used as executive approach. The software is proposed in this paper that converted various data and information to certain Data Model. This software can produce generalization map according to base map using the existing algorithm. Planimetric generalization algorithms and roles are described in this article. Finally small-scale maps with 1:100,000, 1:250,000 and 1:500,000 scale are produced automatically and they are shown at the end.

  6. Gel Generator Technology Viability for Small Scale Production - Indian Experience [Country report: India - GEL Gen.

    International Nuclear Information System (INIS)

    Sarkar, S.K.; Kothalkar, C.; Naskar, P.; Sneha, P.; Saraswathy, P.; Dey, A.C.; Venkatesh, Meera

    2015-01-01

    of the process. After successful completion of feasibility studies and small scale production and supply of gel generators to local hospitals, development of technology for regular production and supply was undertaken. A multidisciplinary core team comprising of chemists and engineers working in close collaboration enabled successful completion of the project. The technology development entailed four major aspects: (i) adaptation of chemical process to automation, (ii) design and erection of a production facility with adequate shielding, (iii) design/fabrication/installation of operation specific gadgets, and (iv) design of a compact, portable, easy to assemble and reusable generator assembly. The production facility, having a capacity to produce up to 25 generators per batch in an 8 hour shift operation, has been operational since the past five years. We report here the salient aspects of technology development and operational experience of producing the gel generators thereby demonstrating the viability of the technology

  7. Assessment of advanced small-scale combined heat and power production

    Energy Technology Data Exchange (ETDEWEB)

    Spitzer, J. [Joanneum Research (Austria)

    1996-12-31

    To increase the share of renewable energy sources, bioenergy has to be used for electricity generation, preferably in combined heat and power (CHP) production systems, besides its traditional use in space heating. The need for small-scale, i.e. below 5 MW{sub el}, CHP production arises from the fact that a considerable portion of the available solid biofuels may not be transported over long distances for economic reasons and that in many cases the heat demand is below 10 MW{sub el} in district heating schemes in communities with less than 10 000 inhabitants. The available technical options have to be assessed with respect to performance, reliability and economy. Such an assessment has been performed in a study where the following options have been compared: Gasification - combustion engine or gas turbine; Combustion - steam turbine/engine; Combustion - hot air turbine; Combustion - Stirling engine. While conventional steam cycle systems are available and reliable they are generally not economical in the power range under consideration. Among the other systems, which are not yet commercially available, the Stirling engine system seems to be attractive in the power range below 500 kW{sub el} and the hot air system could close the gap to the steam cycle systems, i.e. cover the power range between 0.5 and 5.0 MW{sub el}. Gasification schemes seem less suitable: The power generation part (combustion engine and gas turbine) is well established for natural gas, with the combustion engine in the lower (<5 MW{sub el}) and the gas turbine in the higher (>5MW{sub el}) power range. However, the gas quality needed for the operation of a combustion engine requires expensive pre-treatment of the gas from wood gasification so that this scheme is less attractive for the power range under consideration. These conclusions lead to R and D efforts in Austria in two directions: Hot air turbine: A utility demonstration plant is under construction with a power of 1 600 kW{sub el

  8. Assessment of advanced small-scale combined heat and power production

    Energy Technology Data Exchange (ETDEWEB)

    Spitzer, J [Joanneum Research (Austria)

    1997-12-31

    To increase the share of renewable energy sources, bioenergy has to be used for electricity generation, preferably in combined heat and power (CHP) production systems, besides its traditional use in space heating. The need for small-scale, i.e. below 5 MW{sub el}, CHP production arises from the fact that a considerable portion of the available solid biofuels may not be transported over long distances for economic reasons and that in many cases the heat demand is below 10 MW{sub el} in district heating schemes in communities with less than 10 000 inhabitants. The available technical options have to be assessed with respect to performance, reliability and economy. Such an assessment has been performed in a study where the following options have been compared: Gasification - combustion engine or gas turbine; Combustion - steam turbine/engine; Combustion - hot air turbine; Combustion - Stirling engine. While conventional steam cycle systems are available and reliable they are generally not economical in the power range under consideration. Among the other systems, which are not yet commercially available, the Stirling engine system seems to be attractive in the power range below 500 kW{sub el} and the hot air system could close the gap to the steam cycle systems, i.e. cover the power range between 0.5 and 5.0 MW{sub el}. Gasification schemes seem less suitable: The power generation part (combustion engine and gas turbine) is well established for natural gas, with the combustion engine in the lower (<5 MW{sub el}) and the gas turbine in the higher (>5MW{sub el}) power range. However, the gas quality needed for the operation of a combustion engine requires expensive pre-treatment of the gas from wood gasification so that this scheme is less attractive for the power range under consideration. These conclusions lead to R and D efforts in Austria in two directions: Hot air turbine: A utility demonstration plant is under construction with a power of 1 600 kW{sub el

  9. Single-tube hydroponics as a novel idea for small-scale production of crop seed in a plant incubator.

    Science.gov (United States)

    Kuroda, Masaharu; Ikenaga, Sachiko

    2015-01-01

    We present a novel protocol for small-scale production of crop seed in a plant incubator termed "Single-tube hydroponics." Our protocol minimizes the materials and methods for cultivation whereby a large number of independent plants can be cultured in a limited space. This study may aid in the improvement of crop seed components, especially in the cultivation of transgenic plants.

  10. Development and performance evaluation of frustum cone shaped churn for small scale production of butter.

    Science.gov (United States)

    Kalla, Adarsh M; Sahu, C; Agrawal, A K; Bisen, P; Chavhan, B B; Sinha, Geetesh

    2016-05-01

    The present research was intended to develop a small scale butter churn and its performance by altering churning temperature and churn speed during butter making. In the present study, the cream was churned at different temperatures (8, 10 and 12 °C) and churn speeds (35, 60 and 85 rpm). The optimum parameters of churning time (40 min), moisture content (16 %) and overrun (19.42 %) were obtained when cream was churned at churning temperature of 10 °C and churn speed of 60 rpm. Using appropriate conditions of churning temperature and churn speed, high quality butter can be produced at cottage scale.

  11. Upgrading of reformate gas for different applications with focus on small-scale hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Jannasch, Anna-Karin; Silversand, Fredrik [CATATOR AB, Lund (Sweden)

    2004-12-01

    Hydrogen gas or hydrogen rich gas is today used in many different applications, i.e. as fuel in fuel cells or additive in vehicle fuel (i.e. hythane) and as reagent or reducing agent in different industrial product lines. The majority of the hydrogen is produced either via electrolysis or reformation, where this work has entirely been focused on the latter alternative. The overarching aims of this project have been to demonstrate the need for reformate purification for different applications, and then, to investigate different available methods that can be used in order to enable the requested gas clean-up. The different purification methods have been examined with respect to parameters such as operating conditions (temperature, pressure), impurity tolerance, size, weight and cost. Another goal of the project has been to investigate how the reformer fuel type used influences the reformate gas quality and hence, the need for gas purification before the reformate can be fed to e.g. a low temperature polymer membrane fuel cell (PEMFC). For this reason, some experimental work has been performed. First, analysis of the reformate gas composition when natural gas, LPG, gasoline, diesel, kerosene (low and high S-concentration (i.e. JP8)) and ethanol have been processed. The reformation tests were carried out in a small scale reformer unit ({approx} 1 kW H{sub 2}) including Catator's catalyst formulations developed for the steam reforming, the water gas shift and the preferential oxidation reaction, respectively. Verification tests, with synthetic gas blends, including different potential reformate impurities, and with real reformate gas were thereafter performed with a commercial 4-cell PEMFC stack (3-5 W). Finally, some examination and also to some extent further development of Catator's existing gas purification units were made, i.e. chemical (WGS, PROX) and physical (regenerative adsorption). The Pd-alloy membrane seems to be the obvious choice of purification

  12. Rolling at small scales

    DEFF Research Database (Denmark)

    Nielsen, Kim L.; Niordson, Christian F.; Hutchinson, John W.

    2016-01-01

    The rolling process is widely used in the metal forming industry and has been so for many years. However, the process has attracted renewed interest as it recently has been adapted to very small scales where conventional plasticity theory cannot accurately predict the material response. It is well....... Metals are known to be stronger when large strain gradients appear over a few microns; hence, the forces involved in the rolling process are expected to increase relatively at these smaller scales. In the present numerical analysis, a steady-state modeling technique that enables convergence without...

  13. Apparatus for emulsion production in small scale and under controlled shear conditions

    DEFF Research Database (Denmark)

    Adler-Nissen, Jens; Mason, Sarah; Jacobsen, Charlotte

    2004-01-01

    In this article, a rotor-stator apparatus for the production of 5 g batches of emulsion is introduced. Special attention was paid to the design of the apparatus and its construction, ensuring close tolerances in all machined parts. The size of the dispersing gap was 500 µm. The need to prepare...... small quantities of homogeneous emulsion formulations containing costly ingredients formed the impetus for this work. We present a set of emulsion production experiments using a model mayonnaise recipe with a weight percentage of dispersed oil of 80%, and illustrate the effect of rotor speed...... on the average size and size distributions of the resulting oil droplets. These size distributions were within the same range as a commercial mayonnaise. The maximum shear rates and corresponding shear stresses existing in the apparatus at different rotational speeds were estimated. A stabilization time related...

  14. Life cycle assessment of biogas production in small-scale household digesters in Vietnam

    DEFF Research Database (Denmark)

    Vu, T.K.V.; Vu, D.Q.; Jensen, Lars Stoumann

    2015-01-01

    to transport, and the loss of biogas as a result of cracks and the intentional release of excess biogas. In this study, life cycle assessment (LCA) methodology was used to assess the environmental impacts associated with biogas digesters in Vietnam. Handling 1,000 kg of liquid manure and 100 kg of solid manure......Small-scale household digesters have been promoted across Asia as a sustainable way of handling manure. The major advantages are that they produce biogas and reduce odor. However their disadvantages include the low recycling of nutrients, because digestate is dilute and therefore difficult...... in a system with a biogas digester reduced the impact potential from 4.4 kg carbon dioxide (CO 2) equivalents to 3.2 kg CO2 equivalents compared with traditional manure management. However, this advantage could easily be compromised if digester construction is considered in the LCA or in situations where...

  15. Life Cycle Assessment of Biogas Production in Small-scale Household Digesters in Vietnam

    Directory of Open Access Journals (Sweden)

    T. K. V. Vu

    2015-05-01

    Full Text Available Small-scale household digesters have been promoted across Asia as a sustainable way of handling manure. The major advantages are that they produce biogas and reduce odor. However their disadvantages include the low recycling of nutrients, because digestate is dilute and therefore difficult to transport, and the loss of biogas as a result of cracks and the intentional release of excess biogas. In this study, life cycle assessment (LCA methodology was used to assess the environmental impacts associated with biogas digesters in Vietnam. Handling 1,000 kg of liquid manure and 100 kg of solid manure in a system with a biogas digester reduced the impact potential from 4.4 kg carbon dioxide (CO2 equivalents to 3.2 kg CO2 equivalents compared with traditional manure management. However, this advantage could easily be compromised if digester construction is considered in the LCA or in situations where there is an excess of biogas which is intentionally released. A sensitivity analysis showed that biogas digesters could be a means of reducing global warming if methane emissions can be kept low. In terms of eutrophication, farms with biogas digesters had 3 to 4 times greater impacts. In order to make biogas digesters sustainable, methods for recycling digestates are urgently required.

  16. Emergy Perspectives on the Environmental Performance and Sustainability of Small-Scale Gold Production Systems in Ghana

    Directory of Open Access Journals (Sweden)

    Ernest Frimpong Asamoah

    2017-11-01

    Full Text Available Small-scale gold mining is an important component of the Ghanaian economy but it has also caused enormous damage to local ecosystems. In this paper, an emergy analysis was conducted in Ghana to assess the environmental performance and the relative sustainability of two artisanal and small-scale gold production systems: alluvial “dig and wash” and underground “ghetto” mines. Results show that both production systems have high environmental impacts, as indicated by an environmental loading ratio (ELR of 4.31 and environmental sustainability index (ESI of 0.33 for the alluvial system and 2.53 and 0.52 for the underground system, respectively. Concerning the international trade balance, the emergy exchange ratios of the two systems are both lower than one, at, 0.23 and 0.33 for the alluvial and underground systems, respectively, indicating a significant amount of resource loss to foreign regions. This study could assist in the regulation of the small-scale mining sector bearing in mind the unsustainable nature of their activities. In addition, supporting miners to consider land rehabilitation ethics is urgently needed.

  17. Production and milk marketing strategies of small-scale dairy farmers in the South of Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Aline dos Santos Neutzling

    2017-12-01

    Full Text Available Milk production is a socio-economically relevant activity for many small-scale family farms in southern Brazil. The objective of this study was to analyse their production and marketing strategies. A questionnaire was administered to 199 farm households in Rio Grande do Sul State to collect information on farm assets and activities, and particularly on the contribution of milk sale to farm income. Through categorical principal component analysis and two-step clustering, farmers were classified into three types: farmers selling only milk (M; farmers selling cash crops and milk (CM; farmers selling cash crops and surplus milk (Cm. Cattle herd (heads and size of pasture land were larger on M farms (114 ±71.9; 51 ±49.4 ha than on CM (31 ±13.4; 9 ±8.9 ha and Cm (12 ±7.5; 5 ±8.1 ha farms. Livestock husbandry contributed 71, 59 and 16 % to family income on M, CM and Cm farms, respectively. Daily milk production of the individual cow depended on the area cultivated with fodder maize (ha per cow; p ≤ 0.001, on sale of milk to cooperatives or to private companies (p ≤ 0.01, on summer pasture area (ha per cow; p = 0.001 and on daily amount of concentrates offered (kg per cow; p ≤ 0.01. These results indicate that the area available for fodder cultivation is a key factor for milk production on small-scale dairy farms in southern Brazil, while concentrate feeding plays a less important role even for highly market-oriented farms. This must be accounted for when exploring options for strengthening the regional small-scale milk production, in which dairy cooperatives do play an important role.

  18. Small-Scale Coal-Biomass to Liquids Production Using Highly Selective Fischer-Tropsch Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Gangwal, Santosh K. [Southern Research Institute, Durham, NC (United States); McCabe, Kevin [Southern Research Institute, Durham, NC (United States)

    2015-04-30

    The research project advanced coal-to-liquids (CTL) and coal-biomass to liquids (CBTL) processes by testing and validating Chevron’s highly selective and active cobalt-zeolite hybrid Fischer-Tropsch (FT) catalyst to convert gasifier syngas predominantly to gasoline, jet fuel and diesel range hydrocarbon liquids, thereby eliminating expensive wax upgrading operations The National Carbon Capture Center (NCCC) operated by Southern Company (SC) at Wilsonville, Alabama served as the host site for the gasifier slip-stream testing/demonstration. Southern Research designed, installed and commissioned a bench scale skid mounted FT reactor system (SR-CBTL test rig) that was fully integrated with a slip stream from SC/NCCC’s transport integrated gasifier (TRIGTM). The test-rig was designed to receive up to 5 lb/h raw syngas augmented with bottled syngas to adjust the H2/CO molar ratio to 2, clean it to cobalt FT catalyst specifications, and produce liquid FT products at the design capacity of 2 to 4 L/day. It employed a 2-inch diameter boiling water jacketed fixed-bed heat-exchange FT reactor incorporating Chevron’s catalyst in Intramicron’s high thermal conductivity micro-fibrous entrapped catalyst (MFEC) packing to efficiently remove heat produced by the highly exothermic FT reaction.

  19. Productive, economic and environmental effects of optimised feeding strategies in small-scale dairy farms in the Highlands of Mexico

    Directory of Open Access Journals (Sweden)

    José Velarde-Guillén

    2017-06-01

    Full Text Available Since most dairy production in developing countries comes from small farms, there is scope to reduce their contribution to greenhouse gas (GHG emissions. In the highlands of Mexico, the limitations in these systems are high feeding costs. This paper assessed the production, economics and estimated methane emissions from traditional feeding strategies (TFS in 22 small-scale dairy farms compared to optimised feeding strategies (OFS evaluated through on-farm research in eight participating farms in the dry (DS and in the rainy (RS seasons. Results were analysed with a completely randomized design. There were no differences (P>0.05 in milk fat, body condition score (BCS or live weight between TFS and OFS, but there was higher (P

  20. Small-scale production and use of fuelwood of the Bioenergy research programme; Polttopuun pientuotanto ja -kaeyttoe Bioenergian tutkimusohjelmassa

    Energy Technology Data Exchange (ETDEWEB)

    Ryynaenen, S; Tuomi, S

    1997-12-31

    The objective of the research focusing on the small-scale production of fuelwood within the scope of the National Bioenergy research programme (1993-1998) under way in Finland is to promote the use of fuelwood. In addition to the Work Efficiency Institute (TTS-Institute), several manufacturers and organisations have participated in this work. New technology and work methods for the harvesting of fuelwood have been developed for application by the forest owners. Machines and devices intended for the harvesting and chopping into fuelwood of small-diameter trees have been developed to prototype and series production stages. Recyclable handling and distribution units have been developed for the purpose of distributing chopped fuelwood. A computer-based calculation model has been developed for calculating and analysing the costs of producing chipped and chopped fuelwood. A handbook serving the needs of entrepreneurs has been written on the basis of the results of a study focusing on heat entrepreneurship. The aim of the fuelwood use study, carried out under the leadership of VTT, was to eliminate technical obstacle to using fuelwood in detached houses and the category of small buildings. An other aim was to reduce emissions of the flue gases. This was achieved through the development of fireplace structures, catalyzer assisted combustion and heating methods. An automated stoker-assisted burner and a series of boilers designed for biofuels were developed for small buildings. (3 refs.)

  1. Implication of ICT use on productivity and regional development planning among small scale enterprises in Ondo state

    Directory of Open Access Journals (Sweden)

    Afolabi Francis Fatusin

    2018-03-01

    Full Text Available One of the reasons often cited for underdevelopment of African cities and regions is low application of smart technology to improve means of production. This often led to inefficiency which is ultimately reflected in space. This paper investigated the level of ICT usage among small scale manufacturing enterprises in Ondo State. The study also investigated intra-regional variations in use of smart technologies in the industrial subsector and compared same across the three regions of the state. A sample of 352 enterprises was taken from three senatorial regions and nine settlements which were purposively sampled and interviewed using questionnaire. The production and operational system of these firms were observed. The data collected were analysed using descriptive and inferential methods. The study established that proportion of ICT users concentrated more in Ondo Central 45.7% than Ondo south (28.7% and Ondo north (25.6%. It was also discovered that formal small scale enterprises made more use of ICT products, compared with those in the informal sector. Moreover ICT use among enterprises were urban biased as 91.2% of enterprises in this category were located in major towns of Akure, Okitipupa and Ikare, 8.1% in minor towns of Obaile, Ode Aye and Ugbe, with villages of Aponmu Iboropa and Ikoya being relatively insignificant (0.8%. The study established that enterprises that made use of smart technologies tend to be more efficient in terms of production and marketing especially in identification of new markets, networking, subcontracting, security and other linkage benefits. Also, regional industrial development entails not only quantitative growth of industries, but an industry that embrace a new opportunities in innovation, and technology especially in management, record keeping, production, decision making etc.

  2. Fuel from farms: A guide to small-scale ethanol production: Second edition

    Energy Technology Data Exchange (ETDEWEB)

    1982-05-01

    This guide presents the current status of on-farm fermentation ethanol production as well as an overview of some of the technical and economic factors. Tools such as decision and planning worksheets and a sample business plan for use in exploring whether or not to go into ethanol production are given. Specifics in production including information on the raw materials, system components, and operational requirements are also provided. Recommendation of any particular process is deliberately avoided because the choice must be tailored to the needs and resources of each individual producer. The emphasis is on providing the facts necessary to make informed judgments. 98 refs., 14 figs., 9 tabs.

  3. Small-scale production and utilisation of fuelwood. Review of research projects; Puupolttoaineen pientuotanto ja -kaeyttoe. Katsaus tutkimusprojekteihin

    Energy Technology Data Exchange (ETDEWEB)

    Tuomi, S [Work Efficiency Inst., Rajamaeki (Finland)

    1997-12-01

    The goal in the small-scale production of wood fuels in the context of the Bioenergy research programme is to reduce production costs by 20 % when compared to the 1992 cost level. Also, new harvesting technology and new work methods will be developed for forest owners and small-entrepreneurs in the course of the research programme. The goal of the research work will be to improve the competitiveness of harvesting machines, devices and work chains when dealing with small-diameter trees and logging residues. The aim in the development of measuring methods and quality requirements for purchased fuelwood is to eliminate obstacles resulting from the ambiguities in the measuring and quality of fuelwood. The objective of the fuelwood utilisation research is to eliminate technical obstacles and to develop new action models for organising energy generation in the categories of building-specific and district heating. Also, marketing of the new action models to potential entrepreneurs and heating energy purchasers is an important part of the work. The main objective of the work on the development of fireplaces is to reduce fluegas emissions. The main subject of development of heating equipment designed for buildings is stoker burners for wet fuels (orig.)

  4. ECONOMICS ANALYSIS OF OPTIMAL MILK PRODUCTION IN SMALL-SCALE DAIRY FARMING IN YOGYAKARTA, INDONESIA

    Directory of Open Access Journals (Sweden)

    Himawan Arif

    2015-12-01

    Full Text Available Dairy farm, which produces calf and milk jointly, is expected to raise household’s income in rural areas where potential resources are available. This study aims at examing the optimal production of milk and calf by estimating a relationship between both productions. The study was conducted in Sleman,Yogyakartawhere dairy farms exist. Theory used in this study is economies scope in joint production. The results of study indicate that the level of joint production is still low such that there is no degree in economies of scope. Consequently, household’s income generated from this farm has not been maximised. To increase the income, it can be conducted by two consecutive steps. First, is to increase the production milk and calf jointly until the degree of economies of scope reached. Second, is to produce milk and calf in the best combination after reaching economies of scope. Recently, the best way to maximise income is to produce calf as low as possible, and to increase the period of producing milk.  

  5. LABOUR USE IN SMALL-SCALE YAM PRODUCTION IN QUA'AN ...

    African Journals Online (AJOL)

    ... articulate organization of rural labour markets and migrant labour to ensure availability throughout the production season. Key Words: Labour use, Double log (Cobb-Douglas) fuctional form, Marginal analysis, Qua'an Pan Local Government Area, Plateau State. Global Journal of Agricultural Sciences Vol.2(2) 2003: 118- ...

  6. Collective Action for Small-scale Producers of Agricultural Biodiversity Products

    NARCIS (Netherlands)

    Kruijssen, F.; Keizer, M.; Giuliani, A.

    2009-01-01

    The role of well-functioning markets for development is now widely recognized. However the challenge remains to make these markets benefit the poor and the environment. Increasing attention is being given to the potential role markets can play for agrobiodiversity conservation through product

  7. Linking small-scale circulation dynamics with large-scale seasonal production (phytoplankton) in the Southern Ocean

    CSIR Research Space (South Africa)

    Nicholson, S

    2012-10-01

    Full Text Available Understanding the seasonal and intra-seasonal (daily to weekly) changes of the upper ocean and the impact on the primary production in the Southern Ocean is key to better understanding the sensitivities of the global carbon cycle....

  8. Cost calculation model concerning small-scale production of chips and split firewood

    International Nuclear Information System (INIS)

    Ryynaenen, S.; Naett, H.; Valkonen, J.

    1995-01-01

    The TTS-Institute's Forestry Department has developed a computer-based cost calculation model for the production of wood chips and split firewood. This development work was carried out in conjunction with the nation-wide BIOENERGY -research programme. The said calculation model eases and speeds up the calculation of unit costs and resource needs in harvesting systems for wood chips and split firewood. The model also enables the user to find out how changes in the productivity and costs bases of different harvesting chains influences the unit costs of the system as a whole. The undertaking was composed of the following parts: clarification and modification of productivity bases for application in the model as mathematical models, clarification of machine and device costs bases, designing of the structure and functions of the calculation model, construction and testing of the model's 0-version, model calculations concerning typical chains, review of calculation bases, and charting of development needs focusing on the model. The calculation model was developed to serve research needs, but with further development it could be useful as a tool in forestry and agricultural extension work, related schools and colleges, and in the hands of firewood producers. (author)

  9. Impact on food productivity by fossil fuel independence - A case study of a Swedish small-scale integrated organic farm

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, Sheshti [Dept. of Energy and Technology, Swedish Univ. of Agricultural Sciences, Uppsala (Sweden); Belfrage, Kristina [Centre for Sustainable Agriculture, Swedish Univ. of Agricultural Sciences, Uppsala (Sweden); Olsson, Mats [Dept. of Soil and Environment, Swedish Univ. of Agricultural Sciences, Uppsala (Sweden)

    2013-02-15

    The large-scale industrial agriculture that provides the majority of food at present is dependent upon fossil fuels in the form of tractor fuel, mineral fertilizers, pesticides, and irrigation. Yet, the age of cheap and abundant fossil fuels will likely come to an end within the coming decades. In this case study, the productivity of a small-scale farm (8 ha arable land, 5.5 ha meadow, 3.5 ha pasture and 18 ha forest) independent on fossil fuels by using organic methods and draught horse power was investigated. The aim was to quantify its productivity when the animal composition and possible alternatives to tractive power were varied. After an analysis of possible solutions, three scenarios for tractive power were selected: draught horse power, diesel tractor, and combination of draught horse power and rapeseed oil fueled tractor. A model that calculates the amount of food available at the farm in terms of meat, milk egg, and crops, converts it into energy units and calculates how many people can be supplied from the farm was developed. The most reasonable of the scenarios studied was when draught horse power was combined with tractor (and combine harvester) driven on locally produced rapeseed oil. Then the farm will have access to all advantages with the tractor and harvester, e.g., timeliness in harvest and lifting heavy loads, and the renewability and efficiency of draught horse power on smaller fields, and lighter operations. This system was able to support between 66 and 82 persons depending on crop yields, milk yields, meat production, fuel demand for the tractor, and availability of forest grazing. Most likely the production capacity lands on ability to support approximately 68 - 70 persons, and the farm may require fossil fuels to support more than 80 persons. If all farmland globally was to be operated with the same productivity, this would be enough for supplying the global population with food at present.

  10. Waste treatment and energy production from small-scale wastewater digesters.

    Science.gov (United States)

    Lansing, Stephanie; Maile-Moskowitz, Ayella; Eaton, Alexander

    2017-12-01

    Three tubular anaerobic digestion (AD) systems were installed in Haiti to treat black water (toilet-based wastewater), including a three cell 36m 3 clinic digester (CD), a two cell 2m 3 hotel digester (HD), and a three-cell 3m 3 farm digester (FD) for worker use. During digestion, total coliforms were reduced by 99.1%, E. coli by 98.5%, and chemical oxygen demand (COD) by 93.6%. Nutrients in the effluent averaged 99.4mg/L NH 4 + and 10.6mg/L PO 4 2- , producing an effective organic fertilizer. Average biogas production in CD was 108L/d, with 65.4% CH 4 . Survey participants (n=573) were willing to pay $0.10-0.30 per use for sanitation facilities. Seventy-two percent of the rural population surveyed in Cange, Haiti lacked access to improved sanitation due to financial constraints. The economic analysis calculated an investment cost for a shared toilet AD systems of $16-$47 (USD) per person based on daily use at design capacity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Economic Viability of Small Scale Organic Production of Rice, Common Bean and Maize in Goias State, Brazil

    Directory of Open Access Journals (Sweden)

    Alcido Elenor Wander

    2007-04-01

    Full Text Available This study was conducted to assess the economic feasibility of small scale organic production of rice, common bean and maize in Goias State, Brazil. During 2004/05 and 2005/06 growing seasons, rice, common bean and maize were produced at the organic farm of Embrapa Rice and Beans in five mulching systems (fallow, Crotalaria juncea, Cajanus cajan, Mucuna aterrima and Sorghum bicolor , with and without tillage. Soil tillage consisted of heavy disc harrowing followed by light disc harrowing. All operations and used inputs were recorded. Based on those records, the production costs for each crop were estimated for each cropping season. The costs included operations like sowing, ploughing, harrowing, spraying, fertilizer broadcasting and harvesting, as well as inputs like seeds, inoculant strains of Rhizobium, neem oil and organic fertilizers. The benefits include the gross revenue obtained by multiplying the production amount with the market price for non-organic products. For the purpose of analysis of competitiveness of organic production in comparison to conventional farming the market prices assumed were those of conventional production. In the analysis, the costs of certification were not considered yet due to lack of certifiers in the region. For comparison between traits, net revenue, the benefit-cost-ratio (BCR and the break even point were used. In 2004/05 growing season the BCR varied from 0.27 for common bean on S. bicolor mulch system with tillage up to 4.05 for green harvested maize produced after C. juncea in no tillage system. Common bean and rice were not economically viable in this growing season. In 2005/06 growing season the BCR varied between 0.75 for common bean after S. bicolor in tillage system and 4.50 for green harvested maize produced after fallow in no tillage system. In this season common bean was economically viable in leguminous mulching systems and green harvested maize was viable in all mulching systems.

  12. Small-scale production in the Congo basin of low-acid carotene-rich red palm oil

    Directory of Open Access Journals (Sweden)

    Silou Thomas

    2017-09-01

    Full Text Available The red palm oil consumed in the Congo basin come essentially from small-scale production from the dura or tenera varieties (the latter being a hybrid of dura and pisifera. These three varieties are endemic to the Congo basin. The tenera variety is characterized a thick pulp (about 50% of the nut from which 70–90% of oil (based on fresh pulp can be extracted. The dura variety has less pulp (30% of the nut by weight, and gives an oil yield of the same order of magnitude. The oil is extracted from the crushed pulp after a series of mixing steps in hot water at about 60 °C. When obtained from freshly harvested nuts (at most 3 days storage, this oil is rich in carotenoids (800–2600 ppm and polyphenols (5–13 mg/g, and presents low acid values (IA < 5 and peroxide values (IP < 10. Here we describe this traditional production process, widespread in the Congo basin, and suggest innovations that substantially increase the quantity of oil extracted and significantly improve the quality of the end product.

  13. Microbial background flora in small-scale cheese production facilities does not inhibit growth and surface attachment of Listeria monocytogenes.

    Science.gov (United States)

    Schirmer, B C T; Heir, E; Møretrø, T; Skaar, I; Langsrud, S

    2013-10-01

    The background microbiota of 5 Norwegian small-scale cheese production sites was examined and the effect of the isolated strains on the growth and survival of Listeria monocytogenes was investigated. Samples were taken from the air, food contact surfaces (storage surfaces, cheese molds, and brine) and noncontact surfaces (floor, drains, and doors) and all isolates were identified by sequencing and morphology (mold). A total of 1,314 isolates were identified and found to belong to 55 bacterial genera, 1 species of yeast, and 6 species of mold. Lactococcus spp. (all of which were Lactococcus lactis), Staphylococcus spp., Microbacterium spp., and Psychrobacter sp. were isolated from all 5 sites and Rhodococcus spp. and Chryseobacterium spp. from 4 sites. Thirty-two genera were only found in 1 out of 5 facilities each. Great variations were observed in the microbial background flora both between the 5 producers, and also within the various production sites. The greatest diversity of bacteria was found in drains and on rubber seals of doors. The flora on cheese storage shelves and in salt brines was less varied. A total of 62 bacterial isolates and 1 yeast isolate were tested for antilisterial activity in an overlay assay and a spot-on-lawn assay, but none showed significant inhibitory effects. Listeria monocytogenes was also co-cultured on ceramic tiles with bacteria dominating in the cheese production plants: Lactococcus lactis, Pseudomonas putida, Staphylococcus equorum, Rhodococcus spp., or Psychrobacter spp. None of the tested isolates altered the survival of L. monocytogenes on ceramic tiles. The conclusion of the study was that no common background flora exists in cheese production environments. None of the tested isolates inhibited the growth of L. monocytogenes. Hence, this study does not support the hypothesis that the natural background flora in cheese production environments inhibits the growth or survival of L. monocytogenes. Copyright © 2013 American

  14. Small scale power production

    Energy Technology Data Exchange (ETDEWEB)

    Muoniovaara, M [IVO International Ltd, Vantaa (Finland)

    1997-12-31

    IVO International is a major constructor of biomass power plants in Finland and abroad. As a subsidiary of Imatran Voima Oy, the largest power utility in Finland, it has designed and constructed ten power plants owned by IVO Group or others capable of burning biomasses. Sizes of the plants vary from the world`s largest condensing peat-fired power plant of 155 MWe to a 6 MWe combined heat and power producing unit. This article describes the biomass power plants designed and constructed by IVO Group 3 refs.

  15. Small scale power production

    Energy Technology Data Exchange (ETDEWEB)

    Muoniovaara, M. [IVO International Ltd, Vantaa (Finland)

    1996-12-31

    IVO International is a major constructor of biomass power plants in Finland and abroad. As a subsidiary of Imatran Voima Oy, the largest power utility in Finland, it has designed and constructed ten power plants owned by IVO Group or others capable of burning biomasses. Sizes of the plants vary from the world`s largest condensing peat-fired power plant of 155 MWe to a 6 MWe combined heat and power producing unit. This article describes the biomass power plants designed and constructed by IVO Group 3 refs.

  16. Biomass for energy - small scale technologies

    Energy Technology Data Exchange (ETDEWEB)

    Salvesen, F.; Joergensen, P.F. [KanEnergi, Rud (Norway)

    1997-12-31

    The bioenergy markets and potential in EU region, the different types of biofuels, the energy technology, and the relevant applications of these for small-scale energy production are reviewed in this presentation

  17. Biomass for energy - small scale technologies

    Energy Technology Data Exchange (ETDEWEB)

    Salvesen, F; Joergensen, P F [KanEnergi, Rud (Norway)

    1998-12-31

    The bioenergy markets and potential in EU region, the different types of biofuels, the energy technology, and the relevant applications of these for small-scale energy production are reviewed in this presentation

  18. Contribution of family labour to the profitability and competitiveness of small-scale dairy production systems in central Mexico.

    Science.gov (United States)

    Posadas-Domínguez, Rodolfo Rogelio; Arriaga-Jordán, Carlos Manuel; Martínez-Castañeda, Francisco Ernesto

    2014-01-01

    The objective of this work was to determine the effect of family labour on the profitability and competitiveness of small-scale dairy farms in the highlands of Central Mexico. Economic data from 37 farms were analysed from a stratified statistical sampling with a Neyman assignment. Three strata were defined taking herd size as criterion. Stratum 1: herds from 3 to 9 cows plus replacements, Stratum 2: herds from 10 to 19 cows and Stratum 3: herds from 20 to 30 cows. The policy analysis matrix was used as the method to determine profitability and competitiveness. The coefficient of private profitability (CPP) when the economic cost of family labour is included in the cost structure was 8.0 %, 31.0 % and 46.0 %. When the economic cost of family labour is not included, CPP increase to 47.0 %, 57.0 % and 66.0 % for each strata, respectively. The private cost ratio (PCR) when family labour is included was 0.79, 0.51 and 0.42 for strata 1, 2 and 3, respectively. When family labour is not included, the PCR was 0.07, 0.25 and 0.26. Net profit per litre of milk including family labour was US$0.03 l(-1) for Stratum 1, US$0.09 for Stratum 2 and US$0.12 l(-1) for Stratum 3; but increased to $0.12, 0.14 and 0.15, respectively, when the economic cost of family labour is not included. It is concluded that family labour is a crucial factor in the profitability and competitiveness of small-scale dairy production.

  19. A Bayesian Belief Network approach to assess the potential of non wood forest products for small scale forest owners

    Science.gov (United States)

    Vacik, Harald; Huber, Patrick; Hujala, Teppo; Kurtilla, Mikko; Wolfslehner, Bernhard

    2015-04-01

    It is an integral element of the European understanding of sustainable forest management to foster the design and marketing of forest products, non-wood forest products (NWFPs) and services that go beyond the production of timber. Despite the relevance of NWFPs in Europe, forest management and planning methods have been traditionally tailored towards wood and wood products, because most forest management models and silviculture techniques were developed to ensure a sustained production of timber. Although several approaches exist which explicitly consider NWFPs as management objectives in forest planning, specific models are needed for the assessment of their production potential in different environmental contexts and for different management regimes. Empirical data supporting a comprehensive assessment of the potential of NWFPs are rare, thus making development of statistical models particularly problematic. However, the complex causal relationships between the sustained production of NWFPs, the available ecological resources, as well as the organizational and the market potential of forest management regimes are well suited for knowledge-based expert models. Bayesian belief networks (BBNs) are a kind of probabilistic graphical model that have become very popular to practitioners and scientists mainly due to the powerful probability theory involved, which makes BBNs suitable to deal with a wide range of environmental problems. In this contribution we present the development of a Bayesian belief network to assess the potential of NWFPs for small scale forest owners. A three stage iterative process with stakeholder and expert participation was used to develop the Bayesian Network within the frame of the StarTree Project. The group of participants varied in the stages of the modelling process. A core team, consisting of one technical expert and two domain experts was responsible for the entire modelling process as well as for the first prototype of the network

  20. Interactive design of farm conversion : linking agricultural research and farmer learning for sustainable small scale horticulture production in Colombia

    NARCIS (Netherlands)

    Lee, R.A.

    2002-01-01

    Key words: interactive conversion design / vegetable production / small farms / sustainable farming / Colombia / learning processes / facilitation / agricultural research methods

  1. Small scale Entrepreneurship

    DEFF Research Database (Denmark)

    Gretzinger, Susanne; Fietze, Simon; Brem, Alexander

    2018-01-01

    entrepreneurs in a Danish rural area setting. Our results indicate that aspiring entrepreneurs connected to a regional entrepreneurship center, gain access to a wider network and depending on the level of embeddedness they can build new strong relationships or exploit information stemming from new “weak ties......” and harness more benefits. Results also support the fact that the opportunity to get access to the right network for different innovative needs were perceived as being very vital to gaining help in specialized cases (eg. prototyping, contract formulation, etc.). We find that aspiring entrepreneurs have...... different needs depending on their development status and type of innovation. Founders, who are developing or have developed new product innovations, seem to have an increased need for “strong ties” with consultants and those with knowledge about building up a professional network. Founders, who...

  2. Design and evaluation of a no-tillage seeder for small scale vegetable production using a two-wheeled tractor in Coahuila, Mexico

    NARCIS (Netherlands)

    Vries, de J.; Cadena Zapata, M.; Hoogmoed, W.B.

    2009-01-01

    Currently used conventional tillage systems for small-scale vegetable production in the region of Saltillo, Coahuila, Mexico require a considerable amount of hand labor, energy and materials for all activities. Seedbed preparation can require up to 60% of the total production cost in some systems in

  3. Evaluation of hollow fiber and mini perm bioreactors as an alternative to murine ascites for small scale monoclonal antibody production

    International Nuclear Information System (INIS)

    Abdalla, O. M.

    2006-12-01

    The objective of this study was to compare monoclonal antibody production in hollow fiber, mini perm bioreactor systems and murine ascites to determine the feasibility of the bioreactor system as a potential alternative to the use of mice. One hybridoma cell line was grown in hollow fiber, mini perm bioreactor systems and in groups of 5 mice. Mice were primed with 0.5 ml pristane intraperitoneally 14 days prior to inoculation of 1x10 7 hybridoma cells. Each mouse was tapped a maximum of three times for collection of ascites. Bioreactors were harvested three times weekly for 30 days and were monitored by cell counts, cell viability and media consumption. Time and materials logs were maintained. The total quantity of monoclonal antibody produced in 5 mice versus the total production for the two different bioreactors (hollow fiber and mini perm) in 30 days was as follows: cell line 2AC10E6C7 produce 158 mg vs.97.5 mg, vs 21.54 mg respectively. Mean monoclonal antibody concentration ranged from 4.07 to 8.37 mg/ml in murine ascites, from 0.71 to 3.8 mg/ml in hollow fiber bioreactor system, and from 0.035 to 1.06 in mini perm. Although time and material costs were generally greater for the bioreactors, these results suggest that hollow fiber and mini perm bioreactor systems merit further investigations as potentially viable in vitro alternatives to the use of mice for small scale (<1mg) monoclonal antibody production.(Author)

  4. Evaluation of Hollow Fiber And Miniperm Bioreactors as An Alternative to Murine Ascites for Small Scale Monoclonal Antibody Production

    International Nuclear Information System (INIS)

    Abedalla, O. M.

    2007-01-01

    The objective of this study was to compare monoclonal antibody production in hollow fiber, miniPERM bioreactor systems and murine ascites to determine the feasibility of the bioreactor system as a potential alternative to the use of mice. One hybridoma cell line was grown in hollow fiber, miniPERM bioreactor systems and in groups of 5 mice. Mice were primed with 0.5 ml pristane intraperitoneally 14 days prior to inoculation of 1X10 7 hybridoma cells. Each mouse was tapped a maximum of three times for collection of ascites. Bioreactors were harvested three times weekly for 30 days and were monitored by cell counts, cell viability and media consumption. Time and materials logs were maintained. The total quantity of monoclonal antibody produced in 5 mice versus the total production for the two different bioreactors (hollow fiber and miniPERM) in 30 days was as follows: cell line 2AC10E6C7 produce 158 mg vs.97.5 mg; vs 21.54 mg respectively. Mean monoclonal antibody concentration ranged from 4.07 to 8.37 mg/ml in murine ascites, from 0.71 to 3.8 mg/ml in hollow fiber bioreactor system, and from 0.035 to 1.06 in miniPERM. Although time and material costs were generally greater for the bioreactors, these results suggest that hollow fiber and miniPERM bioreactor systems merit further investigations as potentially viable in vitro alternatives to the use of mice for small scale (< 1 g) monoclonal antibody production.

  5. Why small-scale cannabis growers stay small: five mechanisms that prevent small-scale growers from going large scale.

    Science.gov (United States)

    Hammersvik, Eirik; Sandberg, Sveinung; Pedersen, Willy

    2012-11-01

    Over the past 15-20 years, domestic cultivation of cannabis has been established in a number of European countries. New techniques have made such cultivation easier; however, the bulk of growers remain small-scale. In this study, we explore the factors that prevent small-scale growers from increasing their production. The study is based on 1 year of ethnographic fieldwork and qualitative interviews conducted with 45 Norwegian cannabis growers, 10 of whom were growing on a large-scale and 35 on a small-scale. The study identifies five mechanisms that prevent small-scale indoor growers from going large-scale. First, large-scale operations involve a number of people, large sums of money, a high work-load and a high risk of detection, and thus demand a higher level of organizational skills than for small growing operations. Second, financial assets are needed to start a large 'grow-site'. Housing rent, electricity, equipment and nutrients are expensive. Third, to be able to sell large quantities of cannabis, growers need access to an illegal distribution network and knowledge of how to act according to black market norms and structures. Fourth, large-scale operations require advanced horticultural skills to maximize yield and quality, which demands greater skills and knowledge than does small-scale cultivation. Fifth, small-scale growers are often embedded in the 'cannabis culture', which emphasizes anti-commercialism, anti-violence and ecological and community values. Hence, starting up large-scale production will imply having to renegotiate or abandon these values. Going from small- to large-scale cannabis production is a demanding task-ideologically, technically, economically and personally. The many obstacles that small-scale growers face and the lack of interest and motivation for going large-scale suggest that the risk of a 'slippery slope' from small-scale to large-scale growing is limited. Possible political implications of the findings are discussed. Copyright

  6. Morocco - Small-Scale Fisheries

    Data.gov (United States)

    Millennium Challenge Corporation — The final performance evaluation roadmap for the Small-Scale Fisheries Project (PPA-MCC) is developed using a grid constructed around indicators relating to Project...

  7. Emissions from small-scale energy production using co-combustion of biofuel and the dry fraction of household waste.

    Science.gov (United States)

    Hedman, Björn; Burvall, Jan; Nilsson, Calle; Marklund, Stellan

    2005-01-01

    In sparsely populated rural areas, recycling of household waste might not always be the most environmentally advantageous solution due to the total amount of transport involved. In this study, an alternative approach to recycling has been tested using efficient small-scale biofuel boilers for co-combustion of biofuel and high-energy waste. The dry combustible fraction of source-sorted household waste was mixed with the energy crop reed canary-grass (Phalaris Arundinacea L.), and combusted in both a 5-kW pilot scale reactor and a biofuel boiler with 140-180 kW output capacity, in the form of pellets and briquettes, respectively. The chlorine content of the waste fraction was 0.2%, most of which originated from plastics. The HCl emissions exceeded levels stipulated in new EU-directives, but levels of equal magnitude were also generated from combustion of the pure biofuel. Addition of waste to the biofuel did not give any apparent increase in emissions of organic compounds. Dioxin levels were close to stipulated limits. With further refinement of combustion equipment, small-scale co-combustion systems have the potential to comply with emission regulations.

  8. Emissions from small-scale energy production using co-combustion of biofuel and the dry fraction of household waste

    International Nuclear Information System (INIS)

    Hedman, Bjoern; Burvall, Jan; Nilsson, Calle; Marklund, Stellan

    2005-01-01

    In sparsely populated rural areas, recycling of household waste might not always be the most environmentally advantageous solution due to the total amount of transport involved. In this study, an alternative approach to recycling has been tested using efficient small-scale biofuel boilers for co-combustion of biofuel and high-energy waste. The dry combustible fraction of source-sorted household waste was mixed with the energy crop reed canary-grass (Phalaris Arundinacea L.), and combusted in both a 5-kW pilot scale reactor and a biofuel boiler with 140-180 kW output capacity, in the form of pellets and briquettes, respectively. The chlorine content of the waste fraction was 0.2%, most of which originated from plastics. The HCl emissions exceeded levels stipulated in new EU-directives, but levels of equal magnitude were also generated from combustion of the pure biofuel. Addition of waste to the biofuel did not give any apparent increase in emissions of organic compounds. Dioxin levels were close to stipulated limits. With further refinement of combustion equipment, small-scale co-combustion systems have the potential to comply with emission regulations

  9. Inventory of future power and heat production technologies. Partial report Small-scale technology; Inventering av framtidens el- och vaermeproduktionstekniker. Delrapport Smaaskalig teknik

    Energy Technology Data Exchange (ETDEWEB)

    Ridell, Bengt (Grontmij AB (Sweden))

    2008-12-15

    The following techniques for small-scale production have been selected to be studied more carefully, Fuel cells, Photovoltaics, Organic Rankine Cycle (ORC), and Wave power. Of the four selected technologies, fuel cells, solar cells, ORC are appropriate for use in so-called distributed generation, to be used close to a consumer, and possibly also for the production of electricity. Wave power is more like the wind in nature and is probably better suited to be used by power companies for direct input to the transmission grid. None of these technologies are now competitive against buying electricity from the Swedish grid. However, there are opportunities for all to reduce production costs so that they can become competitive alternatives in the future, depending largely on the general development of electricity prices, taxes, delivery reliability, etc. The four different technologies have different development stages and requirements that affect their possibility for a commercial breakthrough. These technologies will probably not all get a breakthrough in Sweden. Small-scale technologies will in the time period up to 2030 not be able to compete with the large-scale technologies that exist in today's power grid. In the longer term the situation may be different. The power system might be reduced in importance if the small scale technologies become cheap, reliable and easy to use. Electricity can then be produced locally, directly related to user needs

  10. The paradoxical impacts of anti-cigarette campaigns in Indonesia: Between production increase and the faith of small-scale tobacco farmers

    Directory of Open Access Journals (Sweden)

    Bagong Suyanto

    2017-06-01

    Full Text Available This article explains the extent to which the anti-tobacco campaigns have brought about a paradoxical impact on Indonesian small-scale tobacco farmers. It draws on empirical studies undertaken in four areas of the Eastern Java Province, and involves 300 respondents. The findings of the survey indicate that while anticigarette campaigns have affected and restricted tobacco production, big distributors and multinational tobacco companies are enjoying more profits. In contrast, small-scale farmers are suffering from more losses caused by mainly three interrelated factors; the narrowing margin of profit, increasingly difficult access to sell tobacco products, and weak bargaining position in the face of the tobacco market.

  11. Production of recombinant antigens and antibodies in Nicotiana benthamiana using 'magnifection' technology: GMP-compliant facilities for small- and large-scale manufacturing.

    Science.gov (United States)

    Klimyuk, Victor; Pogue, Gregory; Herz, Stefan; Butler, John; Haydon, Hugh

    2014-01-01

    This review describes the adaptation of the plant virus-based transient expression system, magnICON(®) for the at-scale manufacturing of pharmaceutical proteins. The system utilizes so-called "deconstructed" viral vectors that rely on Agrobacterium-mediated systemic delivery into the plant cells for recombinant protein production. The system is also suitable for production of hetero-oligomeric proteins like immunoglobulins. By taking advantage of well established R&D tools for optimizing the expression of protein of interest using this system, product concepts can reach the manufacturing stage in highly competitive time periods. At the manufacturing stage, the system offers many remarkable features including rapid production cycles, high product yield, virtually unlimited scale-up potential, and flexibility for different manufacturing schemes. The magnICON system has been successfully adaptated to very different logistical manufacturing formats: (1) speedy production of multiple small batches of individualized pharmaceuticals proteins (e.g. antigens comprising individualized vaccines to treat NonHodgkin's Lymphoma patients) and (2) large-scale production of other pharmaceutical proteins such as therapeutic antibodies. General descriptions of the prototype GMP-compliant manufacturing processes and facilities for the product formats that are in preclinical and clinical testing are provided.

  12. Small-scale household biogas digesters

    DEFF Research Database (Denmark)

    Bruun, Sander; Jensen, Lars Stoumann; Khanh Vu, Van Thi

    2014-01-01

    There are a number of advantages to small-scale biogas production on farms, including savings on firewood or fossil fuels and reductions in odour and greenhouse gas emissions. For these reasons, governments and development aid agencies have supported the installation of biogas digesters. However......, biogas digesters are often poorly managed and there is a lack of proper distribution systems for biogas. This results in methane being released inadvertently through leaks in digesters and tubing, and intentionally when production exceeds demand. As methane has a global warming potential 25 times greater......% of the produced biogas is released, depending on the type of fuel that has been replaced. The limited information available as regards methane leaking from small-scale biogas digesters in developing countries indicates that emissions may be as high as 40%. With the best estimates of global numbers of small...

  13. An evaluation of a small-scale biodiesel production technology: Case study of Mango’o village, Center province, Cameroon

    Science.gov (United States)

    Sarantopoulos, Ioannis; Che, Franklin; Tsoutsos, Theocharis; Bakirtzoglou, Vagios; Azangue, Willy; Bienvenue, Donatien; Ndipen, Frankline Mulluh

    It is an undeniable fact that isolated areas lack sufficient energy resources and that energy supply is central in order to achieve sustainable development goals. On the other hand, agricultural materials, whose trade profit fluctuates in low levels, are produced locally in wide range. As a result, the implementation of an alternative, more effective approach, which ensures the sustainability in social, economical and environmental dimension, is a crucial issue for developing countries. In this particular study, in order to cover the local energy needs, the possibility of installing a small biodiesel plant in a rural area of Cameroon, has been analyzed. The final biodiesel product can also be disposed directly to the market leading to an additional local income. In this paper, both the monthly potential of palm oil in Mango’o region and the recommended biodiesel production process are presented. Some significant benefits that can be achieved are independence from fossil fuels, mechanization of palm oil production process and additional prevention of local depopulation.

  14. Technology Development of an Advanced Small-scale Microchannel-type Process Heat Exchanger (PHE) for Hydrogen Production in Iodine-sulfur Cycle

    Energy Technology Data Exchange (ETDEWEB)

    Sah, Injin; Kim, Chan Soo; Kim, Yong Wan; Park, Jae-Won; Kim, Eung-Seon; Kim, Min-Hwan [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    In this study, ongoing manufacturing processes of the components employed in an advanced small-scale microchannel-type PHE are presented. The components, such as mechanically machined microchannels and a diffusion-bonded stack are introduced. Also, preliminary studies on surface treatment techniques for improving corrosion resistance from the corrosive sulfuric environment will be covered. Ongoing manufacturing process for an advanced small-size microchannel-type PHE in KAERI is presented. Through the preliminary studies for optimizing diffusion bonding condition of Hastelloy-X, a diffusion-bonded stack, consisting of primary and secondary side layer by layer, is scheduled to be fabricated in a few months. Also, surface treatment for enhancing the corrosion resistance from the sulfuric acid environment is in progress for the plates with microchannels. A massive production of hydrogen with electricity generation is expected in a Process Heat Exchanger (PHE) in a Very High Temperature gas-cooled Reactor (VHTR) system. For the application of hydrogen production, a small-scale gas loop for feasibility testing of a laboratory-scale has constructed and operated in Korea Atomic Energy Research Institute (KAERI) as a precursor to an experimental- and a pilot-scale gas loops.

  15. Trading off natural resources and rural livelihoods. A framework for sustainability assessment of small-scale food production in water-limited regions

    Science.gov (United States)

    Recanati, Francesca; Castelletti, Andrea; Dotelli, Giovanni; Melià, Paco

    2017-12-01

    Enhancing local production is key to promoting food security, especially in rural households of low-income countries, but may conflict with limited natural resources and ecosystems preservation. We propose a framework integrating the water-food nexus and a sustainable livelihoods perspective to assess small-scale food production in water-poor regions. We demonstrate it by assessing alternative production scenarios in the Gaza Strip at different spatial scales. At the scale of a single farm, there is a clear conflict among objectives: while cash crops ensure good incomes but contribute scarcely to domestic protein supply, crops performing well from the nutritional and environmental viewpoint are among the worst from the economic one. At the regional scale, domestic production might cover an important fraction of nutritional needs while contributing to household income, but water scarcity impairs the satisfaction of food demand by domestic production alone. Pursuing food security under multiple constraints thus requires a holistic perspective: we discuss how a multidimensional approach can promote the engagement of different stakeholders and allow the exploration of trade-offs between food security, sustainable exploitation of natural resources and economic viability.

  16. Small-scale classification schemes

    DEFF Research Database (Denmark)

    Hertzum, Morten

    2004-01-01

    Small-scale classification schemes are used extensively in the coordination of cooperative work. This study investigates the creation and use of a classification scheme for handling the system requirements during the redevelopment of a nation-wide information system. This requirements...... classification inherited a lot of its structure from the existing system and rendered requirements that transcended the framework laid out by the existing system almost invisible. As a result, the requirements classification became a defining element of the requirements-engineering process, though its main...... effects remained largely implicit. The requirements classification contributed to constraining the requirements-engineering process by supporting the software engineers in maintaining some level of control over the process. This way, the requirements classification provided the software engineers...

  17. Small-scale rural bakery; Maaseudun pienleipomo

    Energy Technology Data Exchange (ETDEWEB)

    Alkula, R.; Malin, A.; Reisbacka, A.; Rytkoenen, A.

    1997-12-31

    The purpose of the study was to clarify how running a small-scale bakery can provide a farming enterprise with its primary or secondary source of livelihood. A questionnaire and interviews were conducted to clarify the current situation concerning small-scale rural bakeries. The experimental part of the study looked into different manners of production, devices used in preparing and processing of doughs, and baking of different kinds of pastries in different types of ovens in laboratory conditions. Based on the results obtained, solutions serving as examples were formulated for small-scale bakeries run with various modes and methods of production. Additionally, market reviews were conducted concerning appropriate equipment for small-scale bakeries. Baking for commercial purposes on the farm is still something new as ca. 80 % of the enterprises covered by the study had operated for no more than five years. Many entrepreneurs (ca. 70 %) expressed a need for supplementary knowledge from some field related to baking. Rural bakeries are small-scale operations with one-person enterprises amounting to 69 % and two-person enterprises to 29 %. Women are primarily responsible for baking. On average, the enterprises baked seven different products, but the amounts baked were usually small. In the experimental part of the study, loaves of rye bread were baked using five different types and sizes of oven accommodating 5-22 loaves of rye bread at the one time. The oven type was found not to affect bread structure. The energy consumption for one ovenful varied between 2.4 and 7.0 kWh, i.e. 0.25-0.43 kWh per kilo. When baking rolls (30-140 rolls at a time), the power consumption varied between 1.2 and 3.5 kWh, i.e. 0.32-0.53 kWh per kilo. The other devices included in the comparative study were an upright deep-freezer, a multi-temperature cabinet and a fermenting cabinet. Furthermore, making rolls by hand was compared to using a machine for the same job, and likewise manual

  18. Developing Techniques for Small Scale Indigenous Molybdenum-99 Production Using LEU Fission at Tajoura Research Center-Libya [Country report: Libya

    International Nuclear Information System (INIS)

    Alwaer, Sami M.

    2015-01-01

    The object of this work was to assist the IAEA by providing the Libyan country report about the Coordination Research Project (CRP), on the subject of “Developing techniques for small scale indigenous Mo-99 production using LEU-foil” which took place over five years and four RCMs. A CRP on this subject was approved in early 2005. The objectives of this CRP are to: transfer know-how in the area of 99 Mo production using LEU targets based on reference technologies from leading laboratories in the field to the participating laboratories in the CRP; develop national work plans based on various stages of technical development and objectives in this field; establish the procedures and protocols to be employed, including quality control and assurance procedures; establish the coordinated activities and programme for preparation, irradiation, and processing of LEU targets [a]; and to compare results obtained in the implementation of the technique in order to provide follow up advice and assistance. Technetium-99m ( 99m Tc), the daughter product of molybdenum-99 ( 99 Mo), is the most commonly utilized medical radioisotope in the world, used for approximately 20-25 million medical diagnostic procedures annually, comprising some 80% of all diagnostic nuclear medicine procedures. National and international efforts are underway to shift the production of medical isotopes from highly enriched uranium (HEU) to low enriched uranium (LEU) targets. A small but growing amount of the current global 99 Mo production is derived from the irradiation of LEU targets. The IAEA became aware of the interest of a number of developing Member States that are seeking to become small scale, indigenous producers of 99 Mo to meet local nuclear medicine requirements. The IAEA initiated Coordinated Research Project (CRP) T.1.20.18 “Developing techniques for small-scale indigenous production of Mo-99 using LEU or neutron activation” in order to assist countries in this field. The more

  19. Spatial modeling of personalized exposure dynamics: the case of pesticide use in small-scale agricultural production landscapes of the developing world

    Directory of Open Access Journals (Sweden)

    Binder Claudia R

    2009-03-01

    Full Text Available Abstract Background Pesticide poisoning is a global health issue with the largest impacts in the developing countries where residential and small-scale agricultural areas are often integrated and pesticides sprayed manually. To reduce health risks from pesticide exposure approaches for personalized exposure assessment (PEA are needed. We present a conceptual framework to develop a spatial individual-based model (IBM prototype for assessing potential exposure of farm-workers conducting small-scale agricultural production, which accounts for a considerable portion of global food crop production. Our approach accounts for dynamics in the contaminant distributions in the environment, as well as patterns of movement and activities performed on an individual level under different safety scenarios. We demonstrate a first prototype using data from a study area in a rural part of Colombia, South America. Results Different safety scenarios of PEA were run by including weighting schemes for activities performed under different safety conditions. We examined the sensitivity of individual exposure estimates to varying patterns of pesticide application and varying individual patterns of movement. This resulted in a considerable variation in estimates of magnitude, frequency and duration of exposure over the model runs for each individual as well as between individuals. These findings indicate the influence of patterns of pesticide application, individual spatial patterns of movement as well as safety conditions on personalized exposure in the agricultural production landscape that is the focus of our research. Conclusion This approach represents a conceptual framework for developing individual based models to carry out PEA in small-scale agricultural settings in the developing world based on individual patterns of movement, safety conditions, and dynamic contaminant distributions. The results of our analysis indicate our prototype model is sufficiently

  20. Design of a Small Scale Pilot Biodiesel Production Plant and Determination of the Fuel Properties of Biodiesel Produced With This Plant

    Directory of Open Access Journals (Sweden)

    Tanzer Eryılmaz

    2014-09-01

    Full Text Available A small scale pilot biodiesel production plant that has a volume of 65 liters/day has been designed, constructed and tested. The plant was performed using oil mixture (50% wild mustard seed oil + 50% refined canola oil and methanol with sodium hydroxide (NaOH catalyst. The fuel properties of biodiesel indicated as density at 15oC (889.64 kg/m3, kinematic viscosity at 40oC (6.975 mm2/s, flash point (170oC, copper strip corrosion (1a, water content (499.87 mg/kg, and calorific value (39.555 MJ/kg, respectively.

  1. Small scale models equal large scale savings

    International Nuclear Information System (INIS)

    Lee, R.; Segroves, R.

    1994-01-01

    A physical scale model of a reactor is a tool which can be used to reduce the time spent by workers in the containment during an outage and thus to reduce the radiation dose and save money. The model can be used for worker orientation, and for planning maintenance, modifications, manpower deployment and outage activities. Examples of the use of models are presented. These were for the La Salle 2 and Dresden 1 and 2 BWRs. In each case cost-effectiveness and exposure reduction due to the use of a scale model is demonstrated. (UK)

  2. Gasification for fuel production in large and small scale polygeneration plants; Foergasning foer braensleproduktion i stor- och smaaskaliga energikombinat

    Energy Technology Data Exchange (ETDEWEB)

    Rodin, Jennie; Wennberg, Olle

    2010-09-15

    This report investigates the possibility of integrating biofuel production through gasification with an existing energy production system. Previous work within Vaermeforsk (report 904, 1012) has concluded that gasification for motor fuel production as a part of a polygeneration plant seems promising when looking at the energy efficiency. However, comparable data between different types of integration, energy plants and fuels was found to be needed in order to get a better understanding of how a gasifier would affect an energy system. The systems studied are the heat- and power production of a bigger city (Goeteborg) and a medium sized city (Eskilstuna), and a pulp mill (Soedra Cell Vaeroe). The latter already runs a commercial gasifier for burner gas production, where the gas is used in the lime kiln. The different types of polygeneration plants have been studied by setting up and evaluating mass- and energy balances for each system. The fuel products that are looked upon in this project are DME, methane, methanol and burner gas. The burner gas is used on site. The case studies have been evaluated based on energy efficiency for fuel production, electricity and district heating. The efficiency is foremost calculated for the higher heating value. In the case of the boiler integrated gasifier in Eskilstuna, the efficiencies have been calculated on the marginal fuel. We have also let the district heating remain unchanged

  3. Biological resources and breeding for improvements in the production of the button mushroom in small-scale farming

    OpenAIRE

    Savoie, Jean-Michel

    2013-01-01

    Gourmet mushrooms may contribute to the development of a new agriculture by addressing the consumer demand and some of the non-nutritional uses of agricultural productions. The value of recycling with gourmet and medicinal mushrooms is clearly understood and wastes can be viewed as positive products, at least in term of providing new economic opportunities and positive environmental consequences. Important cultivated edible and medicinal mushrooms are members of the Agaricus genus. They are s...

  4. The effects of contract farming on efficiency and productivity of small-scale sunflower farmers in Tanzania

    DEFF Research Database (Denmark)

    Henningsen, Arne; Mpeta, Daniel F.; Adem, Anwar S.

    impact on efficiency and productivity is mostly overlooked. This study addresses this salient gap by combining the approaches of Bravo-Ureta, Greene, and Solís (Empirical Economics, 2012) and Rao, Brümmer, and Qaim (AJAE, 2012). We first estimate separate production frontiers for contract farmers and non......-contract farmers that account for potential selection biases, and second, we create a meta-frontier. Using cross-sectional data from sunflower farmers in Tanzania, we find a significant selection bias. Contract farming significantly increases the yield potential but lowers the average group technical efficiency...

  5. Productivity and performance of small scale blast furnaces; Produtividade e performance de altos fornos de pequeno porte

    Energy Technology Data Exchange (ETDEWEB)

    Melo, Vamberto Ferreira de; Grandin, Friedrich Hans G.; Lanna, Pitagoras Gomes de; Castello Branco, Marco Antonio S.C. [Mannesmann SA, Belo Horizonte, MG (Brazil)

    1994-05-01

    This work presents some data concerning the re-start of the blast furnace number 2 of Mannesmann siderurgic company. The main characteristics concerning the operation with 100% coke fuel and the measurements adopted to increase the furnace productivity are described 2 refs., 6 figs., 5 tabs

  6. Environmental impact of cheese production: A case study of a small-scale factory in southern Europe and global overview of carbon footprint.

    Science.gov (United States)

    Canellada, Fernando; Laca, Amanda; Laca, Adriana; Díaz, Mario

    2018-09-01

    The environmental performance of a small-scale cheese factory sited in a NW Spanish region has been analysed by Life Cycle Assessment (LCA) as representative of numerous cheese traditional factories that are scattered through the European Union, especially in the southern countries. Inventory data were directly obtained from this facility corresponding to one-year operation, and the main subsystems involved in cheese production were included, i.e. raw materials, water, electricity, energy, cleaning products, packaging materials, transports, solid and liquid wastes and gas emissions. Results indicated that the environmental impacts derived from cheese making were mainly originated from raw milk production and the natural land transformation was the most affected of the considered categories. On the contrary, the manufacturing of packaging material and other non-dairy ingredients barely influenced on the total impact. Additionally, an average carbon footprint of the cheeses produced in the analysed facility has also been calculated, resulting milk production and pellet boiler emissions the most contributing subsystems. Furthermore, it was notable the positive environmental effect that entailed the direct use of whey as animal feed, which was considered in this study as avoided fodder. Finally, a revision of published works regarding the environmental performance of cheese production worldwide was provided and compared to results found in the present work. According to the analysed data, it is clear that the content of fat and dry extract are determinant factors for the carbon footprint of cheeses, whereas the cheesemaking scale and the geographical area have a very low effect. Copyright © 2018. Published by Elsevier B.V.

  7. Inclusive fitness and differential productivity across the life course determine intergenerational transfers in a small-scale human society.

    Science.gov (United States)

    Hooper, Paul L; Gurven, Michael; Winking, Jeffrey; Kaplan, Hillard S

    2015-03-22

    Transfers of resources between generations are an essential element in current models of human life-history evolution accounting for prolonged development, extended lifespan and menopause. Integrating these models with Hamilton's theory of inclusive fitness, we predict that the interaction of biological kinship with the age-schedule of resource production should be a key driver of intergenerational transfers. In the empirical case of Tsimane' forager-horticulturalists in Bolivian Amazonia, we provide a detailed characterization of net transfers of food according to age, sex, kinship and the net need of donors and recipients. We show that parents, grandparents and siblings provide significant net downward transfers of food across generations. We demonstrate that the extent of provisioning responds facultatively to variation in the productivity and demographic composition of families, as predicted by the theory. We hypothesize that the motivation to provide these critical transfers is a fundamental force that binds together human nuclear and extended families. The ubiquity of three-generational families in human societies may thus be a direct reflection of fundamental evolutionary constraints on an organism's life-history and social organization.

  8. Economic efficiency among small scale poultry farmers in Imo State ...

    African Journals Online (AJOL)

    ... household size and extension, were found to be the significant factors that account for the observed variation in efficiency among the small scale poultry farmers. Keywords: economic efficiency, small scale poultry farmers, stochastic frontier production model. International Journal of Agriculture and Rural Development Vol.

  9. Undermining the myths about small-scale mining

    NARCIS (Netherlands)

    Verbrugge, B.L.P.; Besmanos, B.

    2015-01-01

    Along with many other countries, in recent decades the Philippines –have witnessed a dramatic expansion of small-scale mining (SSM), mostly (but not exclusively)in the form of small-scale gold mining. As can be seen in the graph below (figure 1), official gold production fromSSM has

  10. Tapping the Vast Potential of the Data Deluge in Small-scale Food-Animal Production Businesses: Challenges to Near Real-time Data Analysis and Interpretation.

    Science.gov (United States)

    Vial, Flavie; Tedder, Andrew

    2017-01-01

    Food-animal production businesses are part of a data-driven ecosystem shaped by stringent requirements for traceability along the value chain and the expanding capabilities of connected products. Within this sector, the generation of animal health intelligence, in particular, in terms of antimicrobial usage, is hindered by the lack of a centralized framework for data storage and usage. In this Perspective, we delimit the 11 processes required for evidence-based decisions and explore processes 3 (digital data acquisition) to 10 (communication to decision-makers) in more depth. We argue that small agribusinesses disproportionally face challenges related to economies of scale given the high price of equipment and services. There are two main areas of concern regarding the collection and usage of digital farm data. First, recording platforms must be developed with the needs and constraints of small businesses in mind and move away from local data storage, which hinders data accessibility and interoperability. Second, such data are unstructured and exhibit properties that can prove challenging to its near real-time preprocessing and analysis in a sector that is largely lagging behind others in terms of computing infrastructure and buying into digital technologies. To complete the digital transformation of this sector, investment in rural digital infrastructure is required alongside the development of new business models to empower small businesses to commit to near real-time data capture. This approach will deliver critical information to fill gaps in our understanding of emerging diseases and antimicrobial resistance in production animals, eventually leading to effective evidence-based policies.

  11. Tapping the Vast Potential of the Data Deluge in Small-scale Food-Animal Production Businesses: Challenges to Near Real-time Data Analysis and Interpretation

    Directory of Open Access Journals (Sweden)

    Flavie Vial

    2017-09-01

    Full Text Available Food-animal production businesses are part of a data-driven ecosystem shaped by stringent requirements for traceability along the value chain and the expanding capabilities of connected products. Within this sector, the generation of animal health intelligence, in particular, in terms of antimicrobial usage, is hindered by the lack of a centralized framework for data storage and usage. In this Perspective, we delimit the 11 processes required for evidence-based decisions and explore processes 3 (digital data acquisition to 10 (communication to decision-makers in more depth. We argue that small agribusinesses disproportionally face challenges related to economies of scale given the high price of equipment and services. There are two main areas of concern regarding the collection and usage of digital farm data. First, recording platforms must be developed with the needs and constraints of small businesses in mind and move away from local data storage, which hinders data accessibility and interoperability. Second, such data are unstructured and exhibit properties that can prove challenging to its near real-time preprocessing and analysis in a sector that is largely lagging behind others in terms of computing infrastructure and buying into digital technologies. To complete the digital transformation of this sector, investment in rural digital infrastructure is required alongside the development of new business models to empower small businesses to commit to near real-time data capture. This approach will deliver critical information to fill gaps in our understanding of emerging diseases and antimicrobial resistance in production animals, eventually leading to effective evidence-based policies.

  12. Monitoring of biogenic amines in cheeses manufactured at small-scale farms and in fermented dairy products in the Czech Republic.

    Science.gov (United States)

    Buňková, Leona; Adamcová, Gabriela; Hudcová, Kateřina; Velichová, Helena; Pachlová, Vendula; Lorencová, Eva; Buňka, František

    2013-11-01

    The aim of the study was the monitoring of six biogenic amines (histamine, tyramine, phenylethylamine, tryptamine, putrescine, and cadaverine) and two polyamines (spermidine and spermine) in 112 samples of dairy products purchased in the Czech Republic, namely in 55 cheeses made in small-scale farms and in 57 fermented dairy products. The products were tested at the end of their shelf-life period. Neither tryptamine nor phenylethylamine was detected in the monitored samples; histamine was found only in four cheese samples containing up to 25mg/kg. The contents of spermine and spermidine were low and did not exceed the values of 35 mg/kg. Significant amounts of tyramine, putrescine, and cadaverine occurred especially in cheeses produced from ewe's milk or in long-term ripened cheeses. In about 10% of the tested cheeses, the total concentration of all the monitored biogenic amines and polyamines exceeded the level of 200mg/kg, which can be considered toxicologically significant. In fermented dairy products, the tested biogenic amines occurred in relatively low amounts (generally up to 30 mg/kg) that are regarded safe for the consumer's health. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Steam reforming of methane over Pt/Rh based wire mesh catalyst in single channel reformer for small scale syngas production

    DEFF Research Database (Denmark)

    Sigurdsson, Haftor Örn; Kær, Søren Knudsen

    2012-01-01

    of a catalytic parallel plate type heat exchanger (CPHE) reformer stack, where coated Pt/Rh based wire mesh is used as a catalyst. Heat is supplied to the endothermic reaction with infrared electric heaters. All the experiments were performed under atmospheric pressure and at stable operating conditions......The purpose of this study is to investigate a small scale steam methane reformer for syngas production for a micro combined heat and power (mCPH) unit under different operational conditions. The study presents an experimental analysis of the performance of a specially built single channel...... to evaluate the effect of flow maldistribution in a CPHE reformer stack on the CH4 conversion and H2 yield....

  14. Small Scale LNG in Europe

    International Nuclear Information System (INIS)

    2005-09-01

    The conference has 19 presentation that addresses topics within the economic and marketing aspects, distribution and transmission, size, operation and design of LNG production units, transportation aspects, technology assessment, storage of LNG and risk and safety aspects of the use and production of LNG. Some LNG application cases are also presented

  15. Small Scale LNG in Europe

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-09-15

    The conference has 19 presentation that addresses topics within the economic and marketing aspects, distribution and transmission, size, operation and design of LNG production units, transportation aspects, technology assessment, storage of LNG and risk and safety aspects of the use and production of LNG. Some LNG application cases are also presented.

  16. Small Scale Air Driven Generator

    Science.gov (United States)

    2016-12-01

    ESOI energy stored on invested IC integrated circuit RC radio controlled RPM revolutions per minute UPS uninterruptible power supply...used in microgrid systems. The additional electrical power produced could be enough to offset the power required to start up heavy machinery, or power...include automobile 3 turbochargers and small permanent magnet motors commonly used in remote controlled devices. The pairing of these two technologies

  17. Contributions of Small-Scale Community-Owned Infrastructure (SCI ...

    African Journals Online (AJOL)

    Contributions of Small-Scale Community-Owned Infrastructure (SCI) and Asset ... Descriptive analysis was employed to explain access to productive rural ... for asset maintenance and replacement; support targeted value chains given the ...

  18. Small scale structure on cosmic strings

    International Nuclear Information System (INIS)

    Albrecht, A.

    1989-01-01

    I discuss our current understanding of cosmic string evolution, and focus on the question of small scale structure on strings, where most of the disagreements lie. I present a physical picture designed to put the role of the small scale structure into more intuitive terms. In this picture one can see how the small scale structure can feed back in a major way on the overall scaling solution. I also argue that it is easy for small scale numerical errors to feed back in just such a way. The intuitive discussion presented here may form the basis for an analytic treatment of the small structure, which I argue in any case would be extremely valuable in filling the gaps in our resent understanding of cosmic string evolution. 24 refs., 8 figs

  19. Development of Techniques for Small Scale Indigenous 99Mo Production Using LEU Targets at ICN Pitesti-Romania [Country report: Romania

    International Nuclear Information System (INIS)

    2015-01-01

    Initiation of the IAEA Coordinated Research Project (CRP) “Development Techniques for Small Scale Indigenous 99 Mo Production Using LEU Fission or Neutron Activation” during 2005 allowed Member States to participate through their research organization on contractor arrangement to accomplish the CRP objectives. Among these, the participating research organization Institute for Nuclear Research Pitesti Romania (ICN), was the beneficiary of financial support and Argonne National Laboratory assistance provided by US Department of Energy to the CRP for development of techniques for fission 99 Mo production based on LEU modified CINTICHEM process. The Agency’s role in this field was to assist in the transfer and adaptation of existing technology in order to disseminate a technique, which advances international non-proliferation objectives and promotes sustainable development needs, while also contributing to extend the production capacity for addressing supply shortages from the latest years. The Institute for Nuclear Research, considering the existing good conditions of infrastructure of the research reactor with suitable irradiation conditions for radioisotopes, a post irradiation laboratory with direct transfer of irradiated targets from the reactor and handling of high radioactive sources, and simultaneously the existence of an expanding internal market, decided to undertake the necessary steps in order to produce fission molybdenum. The Institute intends to develop the capability to respond to the domestic needs in cooperation with the IFINN–HH from Bucharest, which is able to perform the last step consisting in the loading of fission molybdenum on chromatography generators and dispensing to the final client. The primary scope of the project is the development of the necessary technological steps and chemical processing steps in order to be able to cover the entire process for fission molybdenum production at the required standard of purity

  20. Designing of network planning system for small-scale manufacturing

    Science.gov (United States)

    Kapulin, D. V.; Russkikh, P. A.; Vinnichenko, M. V.

    2018-05-01

    The paper presents features of network planning in small-scale discrete production. The procedure of explosion of the production order, considering multilevel representation, is developed. The software architecture is offered. Approbation of the network planning system is carried out. This system allows carrying out dynamic updating of the production plan.

  1. Biofiltration and electrochemical treatment for the production of service water from outflows of small-scaled sewage treatment plants; Biofiltration und elektrochemische Behandlung zur Brauchwassererzeugung aus Kleinklaeranlagenablaeufen

    Energy Technology Data Exchange (ETDEWEB)

    Ilian, Jens

    2010-12-14

    Up to the 1990s a mechanical partly biological wastewater treatment was performed at remote locations or collected in reservoirs without outflow. The currently valid legal regulations require a biological treatment of wastewater. Thus, biological small-scale sewage treatment plants experience a broad dissemination recently. Under this aspect, the author of the contribution under consideration reports on the bio filtration and electrochemical treatment in order to produce service water from outflows of small-scale sewage treatment plants. The author investigates the legal regulations, and supplements these regulations by own definitions and requirements on the consideration of a hygienic potential for damage. Additionally, investigations on the cleaning performance of properly operated small-scaled sewage treatment plants are performed. The hygienic risk potential as an inflow condition of a disinfection is determined.

  2. Chemical Transfer (Single Small-Scale) Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Description/History: Chemistry laboratoryThe Chemical Transfer Facility (CTF)  is the only U.S. single small-scale  facility, a single repository for the Army’s...

  3. Small-scale irradiated fuel electrorefining

    International Nuclear Information System (INIS)

    Benedict, R.W.; Krsul, J.R.; Mariani, R.D.; Park, K.; Teske, G.M.

    1993-01-01

    In support of the metallic fuel cycle development for the Integral Fast Reactor (IFR), a small scale electrorefiner was built and operated in the Hot Fuel Examination Facility (HFEF) at Argonne National Laboratory-West. The initial purpose of this apparatus was to test the single segment dissolution of irradiated metallic fuel via either direct dissolution in cadmium or anodic dissolution. These tests showed that 99.95% of the uranium and 99.99% of the plutonium was dissolved and separated from the fuel cladding material. The fate of various fission products was also measured. After the dissolution experiments, the apparatus was upgraded to stady fission product behavior during uranium electrotransport. Preliminary decontamination factors were estimated for different fission products under different processing conditions. Later modifications have added the following capabilities: Dissolution of multiple fuel segments simultaneously, electrotransport to a solid cathode or liquid cathode and actinide recovery with a chemical reduction crucible. These capabilities have been tested with unirradiated uranium-zirconium fuel and will support the Fuel Cycle Demonstration program

  4. The Phenomenology of Small-Scale Turbulence

    Science.gov (United States)

    Sreenivasan, K. R.; Antonia, R. A.

    I have sometimes thought that what makes a man's work classic is often just this multiplicity [of interpretations], which invites and at the same time resists our craving for a clear understanding. Wright (1982, p. 34), on Wittgenstein's philosophy Small-scale turbulence has been an area of especially active research in the recent past, and several useful research directions have been pursued. Here, we selectively review this work. The emphasis is on scaling phenomenology and kinematics of small-scale structure. After providing a brief introduction to the classical notions of universality due to Kolmogorov and others, we survey the existing work on intermittency, refined similarity hypotheses, anomalous scaling exponents, derivative statistics, intermittency models, and the structure and kinematics of small-scale structure - the latter aspect coming largely from the direct numerical simulation of homogeneous turbulence in a periodic box.

  5. To What Extent Do Improved Practices Increase Productivity of Small-Scale Rice Cultivation in A Rain-fed Area? : Evidence from Tanzania

    OpenAIRE

    Yuko Nakano; Yuki Tanaka; Keijiro Otsuka

    2014-01-01

    This paper investigates the impact of training provided by a large-scale private farm on the performance of surrounding small-scale rice farmers in a rain-fed area in Tanzania. We found that the training effectively enhances the adoption of improved rice cultivation practices, paddy yield, and profit of rice cultivation by small-holder farmers. In fact, the trainees achieve paddy yield of 5 tons per hectare on average, which is remarkably high for rain-fed rice cultivation. Our results sugges...

  6. Small scale smugglers in Tamaulipas, Mexico

    Directory of Open Access Journals (Sweden)

    Simón Pedro Izcara Palacios

    2013-07-01

    Full Text Available Small-scale part-time smugglers are embedded in the migrant community itself. They work in the United States for several months before returning to their place of origin to organize, with the help of several assistants, a small group of migrants, who are transported where the coyotes themselves are going. This article analyses small-scale smuggling carried out by Tamaulipas' polleros, who transport to the United States, one or a few times per year, migrants from their hometowns or other neighboring areas in order to be employed in the farming sector.

  7. Quantitative transfer of Escherichia coli O157:H7 to equipment during small-scale production of fresh-cut leafy greens.

    Science.gov (United States)

    Buchholz, Annemarie L; Davidson, Gordon R; Marks, Bradley P; Todd, Ewen C D; Ryser, Elliot T

    2012-07-01

    Postharvest contamination and subsequent spread of Escherichia coli O157:H7 can occur during shredding, conveying, fluming, and dewatering of fresh-cut leafy greens. This study quantified E. coli O157:H7 transfer from leafy greens to equipment surfaces during simulated small-scale commercial processing. Three to five batches (22.7 kg) of baby spinach, iceberg lettuce, and romaine lettuce were dip inoculated with a four-strain cocktail of avirulent, green fluorescent protein-labeled, ampicillinresistant E. coli O157:H7 to contain ∼10(6), 10(4), and 10(2) CFU/g, and then were processed after 1 h of draining at ∼23°C or 24 h of storage at 4°C. Lettuce was shredded using an Urschel TransSlicer at two different blade and belt speeds to obtain normal (5 by 5 cm) and more finely shredded (0.5 by 5 cm) lettuce. Thereafter, the lettuce was step conveyed to a flume tank and was washed and then dried using a shaker table and centrifugal dryer. Product (25-g) and water (40-ml) samples were collected at various points during processing. After processing, product contact surfaces (100 cm(2)) on the shredder (n = 14), conveyer (n = 8), flume tank (n = 11), shaker table (n = 9), and centrifugal dryer (n = 8) were sampled using one-ply composite tissues. Sample homogenates diluted in phosphate or neutralizing buffer were plated, with or without prior 0.45- m m membrane filtration, on Trypticase soy agar containing 0.6% yeast extract supplemented with 100 ppm of ampicillin to quantify green fluorescent protein-labeled E. coli O157:H7 under UV light. During leafy green processing, ∼90% of the E. coli O157:H7 inoculum transferred to the wash water. After processing, E. coli O157:H7 populations were highest on the conveyor and shredder (Ptransfer.

  8. Auto-Thermal Reforming Using Mixed Ion-Electronic Conducting Ceramic Membranes for a Small-Scale H2 Production Plant

    Directory of Open Access Journals (Sweden)

    Vincenzo Spallina

    2015-03-01

    Full Text Available The integration of mixed ionic electronic conducting (MIEC membranes for air separation in a small-to-medium scale unit for H2 production (in the range of 650–850 Nm3/h via auto-thermal reforming of methane has been investigated in the present study. Membranes based on mixed ionic electronic conducting oxides such as Ba0.5Sr0.5Co0.8Fe0.2O3-δ (BSCF give sufficiently high oxygen fluxes at temperatures above 800 °C with high purity (higher than 99%. Experimental results of membrane permeation tests are presented and used for the reactor design with a detailed reactor model. The assessment of the H2 plant has been carried out for different operating conditions and reactor geometry and an energy analysis has been carried out with the flowsheeting software Aspen Plus, including also the turbomachines required for a proper thermal integration. A micro-gas turbine is integrated in the system in order to supply part of the electricity required in the system. The analysis of the system shows that the reforming efficiency is in the range of 62%–70% in the case where the temperature at the auto-thermal reforming membrane reactor (ATR-MR is equal to 900 °C. When the electric consumption and the thermal export are included the efficiency of the plant approaches 74%–78%. The design of the reactor has been carried out using a reactor model linked to the Aspen flowsheet and the results show that with a larger reactor volume the performance of the system can be improved, especially because of the reduced electric consumption. From this analysis it has been found that for a production of about 790 Nm3/h pure H2, a reactor with a diameter of 1 m and length of 1.8 m with about 1500 membranes of 2 cm diameter is required.

  9. Small Scale Hydrocarbon Fire Test Concept

    Directory of Open Access Journals (Sweden)

    Joachim Søreng Bjørge

    2017-11-01

    Full Text Available In the oil and gas industry, hydrocarbon process equipment was previously often thermally insulated by applying insulation directly to the metal surface. Fire protective insulation was applied outside the thermal insulation. In some cases, severe corrosion attacks were observed due to ingress of humidity and condensation at cold surfaces. Introducing a 25 mm air gap to prevent wet thermal insulation and metal wall contact is expected to solve the corrosion issues. This improved insulation methodology does, however, require more space that may not be available when refurbishing older process plants. Relocating structural elements would introduce much hot work, which should be minimized in live plants. It is also costly. The aim of the present study is therefore to develop a test concept for testing fire resistance of equipment protected with only air-gap and thermal insulation, i.e., without the fire-protective insulation. The present work demonstrates a conceptual methodology for small scale fire testing of mockups resembling a section of a distillation column. The mockups were exposed to a small-scale propane flame in a test configuration where the flow rate and the flame zone were optimized to give heat flux levels in the range 250–350 kW/m2. Results are presented for a mockup resembling a 16 mm thick distillation column steel wall. It is demonstrated that the modern distance insulation in combination with the heat capacity of the column wall indicates 30+ minutes fire resistance. The results show that this methodology has great potentials for low cost fire testing of other configurations, and it may serve as a set-up for product development.

  10. Does Actor Perspective Matter? A Case Study of Designing Intervention for Small-Scale Palm Oil Production Enterprises in Kwaebibirem District of Ghana

    NARCIS (Netherlands)

    Osei-Amponsah, C.; Visser, Leontine

    2016-01-01

    Despite the fact that the government of Ghana imports the bulk of its industrial palm oil needs, it still fails to give assistance to about 80 percent of small-scale producers to enhance development in the industry. To design interventions that will be sustainable for and beneficial to these

  11. The small-scale production of hydrogen, with the co-production of electricity and district heat, by means of the gasification of municipal solid waste

    International Nuclear Information System (INIS)

    Hognert, Johannes; Nilsson, Lars

    2016-01-01

    Highlights: • Outline of a process for handling municipal solid waste potentially leading to reduced use of fossil transportation fuels. • The integration of waste gasification into a district heat plant leads to excellent energy efficiency. • Analysis based on actual production data from a district heat plant over the period of one year. • Simulation of a plant with productions of heat, power and gaseous hydrogen. - Abstract: Reducing the use of fossil fuels and increasing the recycling of waste are two important challenges for a sustainable society. Fossil fuels contribute to global warming whilst waste causes the pollution of land, water and air. Alternative fuels and innovative waste management systems are needed to address these issues. In this study a gasification process, fuelled with municipal solid waste, was assumed to be integrated into a heat plant to produce hydrogen, electricity and district heat. A whole system, which includes a gasification reactor, heat plant, steam cycle, pressure swing adsorption, gas turbine and compressors was modelled in Microsoft Excel and an energy balance of the system was solved. Data from the scientific literature were used when setting up the heat and mass balances of the gasification process as well as for assessment of the composition of the syngas. The allocation of energy of the products obtained in the process is 29% hydrogen, 26% electricity and 45% district heat. A significant result of the study is the high energy efficiency (88%) during the cold period of the year when the produced heat in the system is utilized for district heat. The system also shows a competitive energy efficiency (56.5%) all year round.

  12. Small Scale Foundries in Ghana: The challenges

    Directory of Open Access Journals (Sweden)

    Anthony ANDREWS

    2012-08-01

    Full Text Available Small Scale Foundries (SSFs have been in existence for several years in Ghana. The industry has created several jobs for the people of Ghana and has minimized the burden on government to find ways of disposing scrap metals generated within the country. While scrap metals are still being exported, the quantity exported has decreased as a result of recycling by foundrymen in producing various parts. The government of Ghana has not paid special attention to this industry. Nevertheless, individuals and private investors are heavily involved in producing several thousands of tonnes of castings annually generating revenue for the government through taxation as well as helping with metal waste disposal. Metal cast products are sold both locally and internationally to neighbouring countries. The industry is however faced with numerous challenges. These include quality issues due to lack of technical know-how, access to funding from both government and private financial institutions and foundry waste management. To promote this industry, government and private financial institutions must be encouraged to come on board. Policies must be established and proper training programme developed to improve and promote this technology. This could go a long way in reducing the high unemployment rate in Ghana.

  13. A multi scale model for small scale plasticity

    International Nuclear Information System (INIS)

    Zbib, Hussein M.

    2002-01-01

    Full text.A framework for investigating size-dependent small-scale plasticity phenomena and related material instabilities at various length scales ranging from the nano-microscale to the mesoscale is presented. The model is based on fundamental physical laws that govern dislocation motion and their interaction with various defects and interfaces. Particularly, a multi-scale model is developed merging two scales, the nano-microscale where plasticity is determined by explicit three-dimensional dislocation dynamics analysis providing the material length-scale, and the continuum scale where energy transport is based on basic continuum mechanics laws. The result is a hybrid simulation model coupling discrete dislocation dynamics with finite element analyses. With this hybrid approach, one can address complex size-dependent problems, including dislocation boundaries, dislocations in heterogeneous structures, dislocation interaction with interfaces and associated shape changes and lattice rotations, as well as deformation in nano-structured materials, localized deformation and shear band

  14. Cassini RTG's -- Small scale module tests

    International Nuclear Information System (INIS)

    Kelly, C.E.; Klee, P.M.

    1994-01-01

    The Cassini spacecraft, scheduled for a 1997 launch to Saturn, will be powered by three GPHS RTGs (General Purpose Heat Source Radioisotope thermoelectric Generators). The RTGs are the same type as those powering the Galileo and Ulysses spacecraft. Three new converters (F-6, F-7, and F-8) are to be built and one converter (F-2) remaining from the GPHS program will be used. F-6 and F-7 are to be fueled and F-8 serves as a spare converter. In addition, the back-up RTG (F-5) from the Ulysses launch, which is still fueled, will serve as the Cassini back-up RTG. The new RTGs will have a lower fuel loading than in the past and will provide a minimum of 276 watts each at B.O.M. (beginning of mission). The mission length is 10.75 years, at which time these RTGs will provide a minimum of 216 watts and a possible extension to 16 years when the power will be 199 watts. This paper discusses tests performed to date to confirm the successful re-establishment of the unicouple production at Martin Marietta. This production line, shut down 10 years ago, has been restarted and over 1,500 unicouples have been produced to date. Confirmation will be primarily obtained by the performance of three small scale converters in comparison with previously tested modules from the Multi Hundred Watt (MHW) (Voyager) and GPHS (Galileo, Ulysses) programs. Test results to date have shown excellent agreement with the data base

  15. Microcredit Loan Repayment Default among Small Scale ...

    African Journals Online (AJOL)

    The model is applied to primary data from a survey of 200 small scale entrepreneurs in the Upper West Region of Ghana. Results show that enterprise size, interest rate, loan duration, level of profit and loan amount are the simultaneous determinants of probability and rate of default. The study recommends that the National ...

  16. Small Scale Regenerative Desulfurization of Biogas

    NARCIS (Netherlands)

    Linders, M.J.G.; Stille, L.C.; Miedema, M.C.; Groenestijn, J.W. van; Goetheer, E.L.V.

    2016-01-01

    The application of small scale biogas digesters to supply biogas to households in developing countries is well established. The biogas is used for different applications, amongst other cooking. Generally, no further treatment of the biogas is applied. Hydrogen Sulfide (H2S) is present in varying

  17. New markets for small-scale hydro

    International Nuclear Information System (INIS)

    Maurer, E.A.

    1997-01-01

    The market for small and medium sized hydro-electric power plant is more attractive than ever. The boom in Europe has increasingly spread to the emerging countries, and here too small hydro plays an important ecological role. In addition to new plant rehabilitation of 'historical' plant is now a major factor. The last few years have seen a market shift from single machine components to complete plant and systems, requiring a strategy re-think on the part of larger companies. Following the influx of private capital into the power industry, business conditions have also undergone a thorough transformation. In place of 'fast money', hydro power offers the prospect of earning longer-term, sustainable money'. The term small-scale hydro-electric power (or simply 'small hydro') is used slightly differently depending on the country and market. Here, it is used to denote plant with turbines up to 10 MW. (Author)

  18. Biofuels in Africa: growing small-scale opportunities

    Energy Technology Data Exchange (ETDEWEB)

    Sulle, Emmanuel [Tanzania Natural Resources Forum (Tanzania, United Republic of); Fauveaud, Swan [Renewable Energy Group, Environment and Solidarity (France); Vermeulen, Sonja

    2009-11-15

    Global demand for climate-friendly transport fuels is driving vast commercial biofuels projects in developing countries. At the opposite end of the spectrum is small-scale bioenergy production. This offers a way for the poor to meet their energy needs and diversify their livelihoods without compromising food security or environmental integrity. Governments hope that it will be possible to combine the advantages of both large- and small-scale production of biofuels to generate energy security and GDP at the national level, while opening up local opportunities. In Africa, most governments are keen to attract foreign direct investment, and see big business as a strategic means of scaling up rural development. But there is a middle way. By encouraging business models that bridge large and small enterprise, African governments could show that commercial competition can go hand in hand with a range of real local benefits.

  19. Small scale structure formation in chameleon cosmology

    International Nuclear Information System (INIS)

    Brax, Ph.; Bruck, C. van de; Davis, A.C.; Green, A.M.

    2006-01-01

    Chameleon fields are scalar fields whose mass depends on the ambient matter density. We investigate the effects of these fields on the growth of density perturbations on sub-galactic scales and the formation of the first dark matter halos. Density perturbations on comoving scales R<1 pc go non-linear and collapse to form structure much earlier than in standard ΛCDM cosmology. The resulting mini-halos are hence more dense and resilient to disruption. We therefore expect (provided that the density perturbations on these scales have not been erased by damping processes) that the dark matter distribution on small scales would be more clumpy in chameleon cosmology than in the ΛCDM model

  20. Philippines: Small-scale renewable energy update

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-01

    This paper gives an overview of the application of small scale renewable energy sources in the Philippines. Sources looked at include solar, biomass, micro-hydroelectric, mini-hydroelectric, wind, mini-geothermal, and hybrid. A small power utilities group is being spun off the major utility, to provide a structure for developing rural electrification programs. In some instances, private companies have stepped forward, avoiding what is perceived as overwhelming beaurocracy, and installed systems with private financing. The paper provides information on survey work which has been done on resources, and the status of cooperative programs to develop renewable systems in the nation.

  1. Small-scale power production for sustainable development. Households', Utilities' and Retailers' experiences from the market for small-scale solar panels and wind turbines; Smaaskalig elproduktion foer en haallbar utveckling. Hushaalls, energibolags och aaterfoersaeljares erfarenheter av marknaden foer smaaskaliga solpaneler och vindturbiner

    Energy Technology Data Exchange (ETDEWEB)

    Palm, Jenny; Tengvard, Maria

    2009-06-15

    In this report, a special form of small scale renewable solutions marketed towards Swedish households is targeted. During the autumn 2008 the Swedish companies 'Egen El i Stockholm AB' ('Egen El') and 'Home Energy' launched a concept with small scale wind turbines and solar cells that the households connect to the electricity socket so that the own produced electricity can be used directly. The purpose with this report is to analyze how users, retailers and grid companies look upon such small scale production of electricity and discuss what institutional effects own produced energy could have on the electricity market. The main research method used was in-depth interviews. We conducted interviews with representatives of eight retail companies, five grid companies, the industry organization Swedenergy, IKEA Greentech, and 20 households. A main conclusion is that the market concerning households small scale production of electricity is still immature. Though, the media attention that Egen El relieved during spring 2008 has made more households aware of the concept and householders increased interest in the concept is also recognized by other retailers and amongst the grid companies. According to the retailers, it is still hard to make a living from selling these kind of products to household. Nevertheless, they are optimistic and believe that the changes in regulations concerning small scale production of electricity and IKEA's investment in PVs will improve the situation. The grid companies, too, have a positive outlook. Though, they stress a number of problems that could occur with many households producing their own electricity. This is mainly related to security and whether the grid will be able to handle this produced electricity. As for the households, environmental concerns supply the main motive for adopting PVs or micro wind power generation. In some cases, the adopting households have an extensively ecological lifestyle

  2. Training needs of small scale poultry farmers on improved ...

    African Journals Online (AJOL)

    Poultry business is a job opportunity for numerous for earning income and ... needs of the small scale commercial poultry farmers to improve poultry production ... strategies (88%) while only 24.1% of the respondents need training on types of ...

  3. A Success Story of Organizing Small Scale Farmers in Kenya

    DEFF Research Database (Denmark)

    Buch-Hansen, Mogens

    2012-01-01

    , but not least to be used in PES schemes. The article emphasizes vertical integration and production diversification, enabling market conditions, and democratization as the main factors in KTDA’s success that could possibly be replicated in promoting small scale farmers participating in the post-Kyoto carbon...

  4. Degradation mechanisms of small scale piping systems

    International Nuclear Information System (INIS)

    Bartonicek, J.; Koenig, G.; Blind, D.

    1996-01-01

    Operational experience shows that many degradation mechanisms can have an effect on small-scale piping systems. We can see from the analyses carried out that the degradation which has occurred is primarily linked with the fact that these piping systems were classified as being of low safety relevance. This is mainly due to such components being classified into low safety relevance category at the design stage, as well as to the low level of operational monitoring. Since in spite of the variety of designs and operational modes the degradation mechanisms detected may be attributed to the piping systems, we can make decisive statements on how to avoid such degradation mechanisms. Even small-scale piping systems may achieve guaranteed integrity in such cases by taking the appropriate action. (orig.) [de

  5. Small-scale tearing mode in tokamaks

    International Nuclear Information System (INIS)

    Ivanov, N.V.

    1983-01-01

    Considerations are given on the possible effect of small-scale tearing mode with m >> 1 on the plasma electron thermal conductivity in a tokamak. The estimate of the electron thermal conductivity coefficient is obtained. Calculation results are compared with experimental data. The calculated dependence of radial distribution of electron temperature is shown to vary weakly with the tn(m 2 /m 1 ) alteration everywhere, except for the vicinity of point r approximately 0

  6. a Model Study of Small-Scale World Map Generalization

    Science.gov (United States)

    Cheng, Y.; Yin, Y.; Li, C. M.; Wu, W.; Guo, P. P.; Ma, X. L.; Hu, F. M.

    2018-04-01

    With the globalization and rapid development every filed is taking an increasing interest in physical geography and human economics. There is a surging demand for small scale world map in large formats all over the world. Further study of automated mapping technology, especially the realization of small scale production on a large scale global map, is the key of the cartographic field need to solve. In light of this, this paper adopts the improved model (with the map and data separated) in the field of the mapmaking generalization, which can separate geographic data from mapping data from maps, mainly including cross-platform symbols and automatic map-making knowledge engine. With respect to the cross-platform symbol library, the symbol and the physical symbol in the geographic information are configured at all scale levels. With respect to automatic map-making knowledge engine consists 97 types, 1086 subtypes, 21845 basic algorithm and over 2500 relevant functional modules.In order to evaluate the accuracy and visual effect of our model towards topographic maps and thematic maps, we take the world map generalization in small scale as an example. After mapping generalization process, combining and simplifying the scattered islands make the map more explicit at 1 : 2.1 billion scale, and the map features more complete and accurate. Not only it enhance the map generalization of various scales significantly, but achieve the integration among map-makings of various scales, suggesting that this model provide a reference in cartographic generalization for various scales.

  7. Enhancing the Productivity of High Value Crops and Income Generation with Small-Scale Irrigation Technologies in Kenya. Final Report 2009-2013

    International Nuclear Information System (INIS)

    2014-02-01

    The project was implemented by the Kenya Agricultural Research Institute in collaboration with key irrigation stakeholders including Horticultural Crops Development Authority (HCDA), G North and Son limited, Kenya Irrigation and Drainage Association (KIDA), Jomo Kenyatta University of Agriculture and Technology (JKUAT), Greenbelt Movement and Ministry of Agriculture. The objective was to develop and pilot test appropriate irrigation systems (methods and related water/nutrient management practices) for small-scale farmers for increasing yield, quality of high value crops and farmers income to improved livelihood. The project built on earlier work on low head drip irrigation in Kenya involving KARI led promotion among the peri-urban and rural communities. The Equipment used include Neutron Probe Hydroprobe, Ammonium Sulphate Fertilizers (5% a.e), drip irrigation kits, MoneyMaker irrigation pumps, Pessl imetos weather station, SDEC tensimetre and tensiometers), Venturi injectors, among others.

  8. 2010 Thin Film & Small Scale Mechanical Behavior Gordon Research Conference

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Thomas Balk

    2010-07-30

    Over the past decades, it has been well established that the mechanical behavior of materials changes when they are confined geometrically at least in one dimension to small scale. It is the aim of the 2010 Gordon Conference on 'Thin Film and Small Scale Mechanical Behavior' to discuss cutting-edge research on elastic, plastic and time-dependent deformation as well as degradation mechanisms like fracture, fatigue and wear at small scales. As in the past, the conference will benefit from contributions from fundamental studies of physical mechanisms linked to material science and engineering reaching towards application in modern applications ranging from optical and microelectronic devices and nano- or micro-electrical mechanical systems to devices for energy production and storage. The conference will feature entirely new testing methodologies and in situ measurements as well as recent progress in atomistic and micromechanical modeling. Particularly, emerging topics in the area of energy conversion and storage, such as material for batteries will be highlighted. The study of small-scale mechanical phenomena in systems related to energy production, conversion or storage offer an enticing opportunity to materials scientists, who can provide new insight and investigate these phenomena with methods that have not previously been exploited.

  9. Self-similarity of high-pT hadron production in cumulative processes and violation of discrete symmetries at small scales (suggestion for experiment)

    International Nuclear Information System (INIS)

    Tokarev, M.V.; Zborovsky, I.

    2009-01-01

    The hypothesis of self-similarity of hadron production in relativistic heavy ion collisions for search for phase transition in a nuclear matter is discussed. It is offered to use the established features of z-scaling for revealing signatures of new physics in cumulative region. It is noted that selection of events on centrality in cumulative region could help to localize a position of a critical point. Change of parameters of the theory (a specific heat and fractal dimensions) near to a critical point is considered as a signature of new physics. The relation of the power asymptotic of ψ(z) at high z, anisotropy of momentum space due to spontaneous symmetry breaking, and discrete (C, P, T) symmetries is emphasized

  10. Appendix - A small scale research review

    DEFF Research Database (Denmark)

    Larsen, Lea Lund

    over two questions asked in the abstract concerning workshop C - Effects of teacher training in lifelong learning - at the current ASEM conference. At first it is asked what do we already know about teacher training effects in relation to adult learners? This will be identified by a search...... for systematic reviews in the international This will be identified by a search for systematic reviews in the international clearinghouses and afterwards by a small scale mapping done in the pedagogic databaseERIC. The second question sounds: which methods can be used to measure the effects of teacher...... training? This will be illustrated by describing a research design in progress at the National Centre of Competence Development, DK, regarding a program where teachers are taught Cooperative Learning as a pedagogical and didactical method. This appendix concerns the first question. In search for empiric results concerning: What do...

  11. Small scale soft x-ray lasers

    International Nuclear Information System (INIS)

    Skinner, C.H.; DiCicco, D.S.; Kim, D.; Voorhees, D.; Suckewer, S.

    1990-01-01

    The widespread application of soft x-ray laser technology is contingent on the development of small scale soft x-ray lasers that do not require large laser facilities. Progress in the development of soft x-ray lasers pumped by a Nd laser of energy 6-12J is reported below. Application of an existing soft x-ray laser to x-ray microscopy has begun. A soft x-ray laser of output energy 1-3 mJ at 18,2 nm has been used to record high resolution images of biological specimens. The contact images were recorded on photoresist which was later viewed in a scanning electron microscope. The authors present a composite optical x-ray laser microscope design

  12. Cold dark matter: Controversies on small scales.

    Science.gov (United States)

    Weinberg, David H; Bullock, James S; Governato, Fabio; Kuzio de Naray, Rachel; Peter, Annika H G

    2015-10-06

    The cold dark matter (CDM) cosmological model has been remarkably successful in explaining cosmic structure over an enormous span of redshift, but it has faced persistent challenges from observations that probe the innermost regions of dark matter halos and the properties of the Milky Way's dwarf galaxy satellites. We review the current observational and theoretical status of these "small-scale controversies." Cosmological simulations that incorporate only gravity and collisionless CDM predict halos with abundant substructure and central densities that are too high to match constraints from galaxy dynamics. The solution could lie in baryonic physics: Recent numerical simulations and analytical models suggest that gravitational potential fluctuations tied to efficient supernova feedback can flatten the central cusps of halos in massive galaxies, and a combination of feedback and low star formation efficiency could explain why most of the dark matter subhalos orbiting the Milky Way do not host visible galaxies. However, it is not clear that this solution can work in the lowest mass galaxies, where discrepancies are observed. Alternatively, the small-scale conflicts could be evidence of more complex physics in the dark sector itself. For example, elastic scattering from strong dark matter self-interactions can alter predicted halo mass profiles, leading to good agreement with observations across a wide range of galaxy mass. Gravitational lensing and dynamical perturbations of tidal streams in the stellar halo provide evidence for an abundant population of low-mass subhalos in accord with CDM predictions. These observational approaches will get more powerful over the next few years.

  13. Profitability and sustainability of small - medium scale palm biodiesel plant

    Science.gov (United States)

    Solikhah, Maharani Dewi; Kismanto, Agus; Raksodewanto, Agus; Peryoga, Yoga

    2017-06-01

    The mandatory of biodiesel application at 20% blending (B20) has been started since January 2016. It creates huge market for biodiesel industry. To build large-scale biodiesel plant (> 100,000 tons/year) is most favorable for biodiesel producers since it can give lower production cost. This cost becomes a challenge for small - medium scale biodiesel plants. However, current biodiesel plants in Indonesia are located mainly in Java and Sumatra, which then distribute biodiesel around Indonesia so that there is an additional cost for transportation from area to area. This factor becomes an opportunity for the small - medium scale biodiesel plants to compete with the large one. This paper discusses the profitability of small - medium scale biodiesel plants conducted on a capacity of 50 tons/day using CPO and its derivatives. The study was conducted by performing economic analysis between scenarios of biodiesel plant that using raw material of stearin, PFAD, and multi feedstock. Comparison on the feasibility of scenarios was also conducted on the effect of transportation cost and selling price. The economic assessment shows that profitability is highly affected by raw material price so that it is important to secure the source of raw materials and consider a multi-feedstock type for small - medium scale biodiesel plants to become a sustainable plant. It was concluded that the small - medium scale biodiesel plants will be profitable and sustainable if they are connected to palm oil mill, have a captive market, and are located minimally 200 km from other biodiesel plants. The use of multi feedstock could increase IRR from 18.68 % to 56.52 %.

  14. Productivity in small dairy farms

    International Nuclear Information System (INIS)

    2007-12-01

    Over the past 10 years the IAEA has assisted the Ministerio de Agricultura y Ganaderia de la Republica del Paraguay in the area of animal production, through technical cooperation projects and research programs with emphasis on milk production. This will got the laboratory equipment, provision of materials and chemical reagents, as well as the training of technicians Paraguayans in specialized centers abroad, which enabled techniques used in the RIA and Ultrasound, used to monitor the reproductive and officials artificial insemination of cattle, with the consequent improvement in milk production [es

  15. N2O emission hotspots at different spatial scales and governing factors for small scale hotspots

    International Nuclear Information System (INIS)

    Heuvel, R.N. van den; Hefting, M.M.; Tan, N.C.G.; Jetten, M.S.M.; Verhoeven, J.T.A.

    2009-01-01

    Chronically nitrate-loaded riparian buffer zones show high N 2 O emissions. Often, a large part of the N 2 O is emitted from small surface areas, resulting in high spatial variability in these buffer zones. These small surface areas with high N 2 O emissions (hotspots) need to be investigated to generate knowledge on the factors governing N 2 O emissions. In this study the N 2 O emission variability was investigated at different spatial scales. Therefore N 2 O emissions from three 32 m 2 grids were determined in summer and winter. Spatial variation and total emission were determined on three different scales (0.3 m 2 , 0.018 m 2 and 0.0013 m 2 ) at plots with different levels of N 2 O emissions. Spatial variation was high at all scales determined and highest at the smallest scale. To test possible factors inducing small scale hotspots, soil samples were collected for slurry incubation to determine responses to increased electron donor/acceptor availability. Acetate addition did increase N 2 O production, but nitrate addition failed to increase total denitrification or net N 2 O production. N 2 O production was similar in all soil slurries, independent of their origin from high or low emission soils, indicating that environmental conditions (including physical factors like gas diffusion) rather than microbial community composition governed N 2 O emission rates

  16. Total Productivity Management in Small Industries

    OpenAIRE

    FARAJPOUR-KHANAPOSHTANI, Ghassem; HAYATI, Seyyed Iman

    2015-01-01

    Abstract. The importance of small businesses and SME's has been well established in the literature of the world economy. Thus, both industrialized and developing countries, development, support of small businesses as part and parcel of their productivity strategies have. Small industries are a major driver of employment, economic growth and productivity. About 80% of all companies in the world are less than 10 cases of human resources, so 95% of industries in the UK, Spain and Finland and 94 ...

  17. Small-Scale Renewable Energy Converters for Battery Charging

    Directory of Open Access Journals (Sweden)

    Mohd Nasir Ayob

    2018-03-01

    Full Text Available This paper presents two wave energy concepts for small-scale electricity generation. In the presented case, these concepts are installed on the buoy of a heaving, point-absorbing wave energy converter (WEC for large scale electricity production. In the studied WEC, developed by Uppsala University, small-scale electricity generation in the buoy is needed to power a tidal compensating system designed to increase the performance of the WEC in areas with high tides. The two considered and modeled concepts are an oscillating water column (OWC and a heaving point absorber. The results indicate that the OWC is too small for the task and does not produce enough energy. On the other hand, the results show that a hybrid system composed of a small heaving point absorber combined with a solar energy system would be able to provide a requested minimum power of around 37.7 W on average year around. The WEC and solar panel complement each other, as the WEC produces enough energy by itself during wintertime (but not in the summer, while the solar panel produces enough energy in the summer (but not in the winter.

  18. Small scale combined woodgas power plant

    International Nuclear Information System (INIS)

    Gulbis, V.

    2003-01-01

    As a first attempt to introduce biomass gasification technology in Latvia at the Faculty of Engineering of Latvia University of Agriculture an integral small scale combined heat and power (CHP) system based on a used Russian-made diesel-alternator set with electrical output 100 kWe was developed. The diesel is converted to dual fuel gas engine, using producer gas as the main fuel and gas oil as pilot fuel. To get sufficiently clean (tar content ≤ 250 mg/m 3 ) woodgas for using in IC engine a downdraft type of gasifier was chosen designed and constructed on the IMBERT gasifier principles. The test runs of the first experimental model showed that the engine does not develop expected power because of high resistance of gasifier and gas cleaning system does not work sufficiently enough. There was rather high level of tar content in woodgas because the temperature in the reduction zone was low. Calculations were carried out and new technological scheme of gasification system was worked out, introducing innovative ideas aimed on improving the working parameters (author)

  19. Hoopa Valley Small Scale Hydroelectric Feasibility Project

    Energy Technology Data Exchange (ETDEWEB)

    Curtis Miller

    2009-03-22

    This study considered assessing the feasibility of developing small scale hydro-electric power from seven major tributaries within the Hoopa Valley Indian Reservation of Northern California (http://www.hoopa-nsn.gov/). This study pursued the assessment of seven major tributaries of the Reservation that flow into the Trinity River. The feasibility of hydropower on the Hoopa Valley Indian Reservation has real potential for development and many alternative options for project locations, designs, operations and financing. In order to realize this opportunity further will require at least 2-3 years of intense data collection focusing on stream flow measurements at multiple locations in order to quantify real power potential. This also includes on the ground stream gradient surveys, road access planning and grid connectivity to PG&E for sale of electricity. Imperative to this effort is the need for negotiations between the Hoopa Tribal Council and PG&E to take place in order to finalize the power rate the Tribe will receive through any wholesale agreement that utilizes the alternative energy generated on the Reservation.

  20. Small scale imaging using ultrasonic tomography

    International Nuclear Information System (INIS)

    Zakaria, Z.; Abdul Rahim, R.; Megat Ali, M.S.A.; Baharuddin, M.Y.; Jahidin, A.H.

    2009-01-01

    Ultrasound technology progressed through the 1960 from simple A-mode and B-mode scans to today M-mode and Doppler two dimensional (2-D) and even three dimensional (3-D) systems. Modern ultrasound imaging has its roots in sonar technology after it was first described by Lord John Rayleigh over 100 years ago on the interaction of acoustic waves with media. Tomography technique was developed as a diagnostic tool in the medical area since the early of 1970s. This research initially focused on how to retrieve a cross sectional images from living and non-living things. After a decade, the application of tomography systems span into the industrial area. However, the long exposure time of medical radiation-based method cannot tolerate the dynamic changes in industrial process two phase liquid/ gas flow system. An alternative system such as a process tomography systems, can give information on the nature of the flow regime characteristic. The overall aim of this paper is to investigate the use of a small scale ultrasonic tomography method based on ultrasonic transmission mode tomography for online monitoring of liquid/ gas flow in pipe/ vessel system through ultrasonic transceivers application. This non-invasive technique applied sixteen transceivers as the sensing elements to cover the pipe/ vessel cross section. The paper also details the transceivers selection criteria, hardware setup, the electronic measurement circuit and also the image reconstruction algorithm applied. The system was found capable of visualizing the internal characteristics and provides the concentration profile for the corresponding liquid and gas phases. (author)

  1. Supply of wood fuel from small-scale woodlands for small-scale heating

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-07-01

    This report summarises the findings of a study aimed at stimulating a market for wood fuels. A desk study of harvesting in existing small woodland was conducted, and thirteen case studies covering early broadleaved thinnings, mixed broadleaved coppice, and crownwood, scrub and residues were examined to obtain information on woodland types, wood fuel supply, and combustion equipment. Details are given of the measurement of moisture content of woodchips and stacked roundwood, wood volume and green density, harvesting options, crop and site variables, and production and costs of wood fuels. Usage of wood fuels, and the drying of small roundwood was considered. (UK)

  2. Small scale pelletizing equipment for agriculture; Smaaskalig pelleteringsanlaeggning foer lantbruket

    Energy Technology Data Exchange (ETDEWEB)

    Paulrud, Susanne (The Swedish Environmental Research Inst. Ltd., Stockholm (Sweden)); Wallin, Mikael (Sweden Powers Chippers AB, Boraas (Sweden))

    2009-06-15

    Refining agricultural raw materials is one way for farmers to increase the value of their products. For example, briquettes or pellets made from straw, reed canary grass or hemp can sell for a higher price than in loose or baled forms. The aim of this project was to develop and build a plant for small-scale production of pellets on the farm. Working together with the farmer, the plant would then be tested and adapted for small-scale production of pellets from straw, reed canary grass and hemp. The project also aimed to investigate and summarise suitable systems and solutions for breaking up bales in preparation for use in the pellets module. A pelleting system has been developed and built as a container module (measuring 6 x 2.80 x 2.50 m) by Sweden Power Chippers (SPC). The container system includes a fuel store with push floor, a grinder, an SPC pellet press (pp150, capacity 150 kg/hour for woodbased material), a conveyor belt and a cooling system. The practical operation of the plant was tested on two Swedish farms: Laattra gaard in Vingaaker and Ek gaard in Vara. The bales were broken up in preparation for pelleting using a straw mill of model Tomahawk 505M. The project has demonstrated that the SPC plant has the capacity to be used for agricultural pelleting of fuels from straw, canary reed grass and hemp. Some modification and continued adjustment of the feed system for the fuel remains to be done in order to optimise and ensure the reliability of the pelleting process. A certain amount of modifications to the plant is required to enable cost-effective transportation between different locations. Tests showed that each batch of fuel was unique, even from the same raw material, and that optimisation of the dies is necessary for each specific case. Training is required to run the plant. The farmers have been able to run the plant themselves, for example, starting up the plant, changing the sieve on the grinder, changing dies etc. In order for such small-scale

  3. Small-Scale Milk Processing, Utilization and Marketing of Traditional Dairy Products in Bahir Dar Zuria and Mecha Districts, Northwestern Ethiopia

    OpenAIRE

    Eyassu Seifu; Asaminew Tassew

    2014-01-01

    This study was conducted to assess processing, utilization and marketing of traditional dairy products produced in Bahir Dar Zuria and Mecha districts in Northwestern Ethiopia. A single-visit-multiple-subject formal survey was conducted to collect data. A total of 150 households (75 households from each district) were individually interviewed using a semi-structured questionnaire. The major dairy products produced in the study area include butter, ghee, Ayib, Arera (defatted sour milk), Ergo ...

  4. The legalization of small scale mining in Colombia

    Directory of Open Access Journals (Sweden)

    Alexandra Urán

    2013-11-01

    Full Text Available The following article presents conceptual and analytical elements that allow us to broaden the debate about the legalization of the mining in Colombia. Looking for items to be able to propose alternatives in order to consolidate a new mining process socially and environmentally sustainable, claiming the value of the ancestral practices and forms of the redistributive production. To this end, it is necessary to start with the discussion of the concepts of formalization and legality, so that we can generate a theoretical framework that will allow us to explore such delicate matter, we will continue to make the framework socio-political, in which it is based that strategy. Then there is a brief context of thereformulation of legal mining, focusing our attention particularly standards which involves or has effects on artisanal mining and/or small-scale mining. There we will find ourselves with a debate on the typology of the mining and the current difficulties to define schemasof legalization or formalization of small-scale mining in Colombia. To conclude with a proposal to formalize as a mechanism of transition to an administrative system - legislativethat will connect more effectively with the realities and skills of the ethnic communities that practice small-scale mining.

  5. traditional medicinal uses of small mammal products

    African Journals Online (AJOL)

    Dr. Nelson Boniface

    hunted small mammals mainly by dogs for cultural and ornamental reasons. Products of African ... (WHO) defines traditional medicine as ''health practices ... particularly in Asian countries. ..... Ntiamoa- Baidu Y 1992 Local Perceptions and.

  6. Dimensional analysis of small-scale steam explosion experiments

    International Nuclear Information System (INIS)

    Huh, K.; Corradini, M.L.

    1986-01-01

    Dimensional analysis applied to Nelson's small-scale steam explosion experiments to determine the qualitative effect of each relevant parameter for triggering a steam explosion. According to experimental results, the liquid entrapment model seems to be a consistent explanation for the steam explosion triggering mechanism. The three-dimensional oscillatory wave motion of the vapor/liquid interface is analyzed to determine the necessary conditions for local condensation and production of a coolant microjet to be entrapped in fuel. It is proposed that different contact modes between fuel and coolant may involve different initiation mechanisms of steam explosions

  7. The potential for the production of bioenergy for lighting and cooking using Jatropha (Jatropha curcas L. Euphorbiaceae) by small scale farmers on the Kenyan coast

    OpenAIRE

    Boerstler, Fritjof

    2010-01-01

    The overall objective of this study is to examine the potential of introducing renewable biomass for a decentralized household energy provision in rural areas at the Kenyan South Coast. The main question posed in this research is whether the renewable products of an oil tree and related energy end-use appliances could potentially be a cheap, widely available and socially accepted substitute for kerosene and traditional biomass. The research data and results are based on a UNDP GEF SGP funded...

  8. The development for small scale soft X-ray spectrometer

    International Nuclear Information System (INIS)

    Sun Kexu; Jiang Shaoen; Yi Rongqing; Cui Yanli

    2004-12-01

    For the development of small-scale soft X-ray spectrometer, first, some small-scale soft X-ray detection elements are developed, it is included GaAs irradiated with neutron, GaAs irradiated with proton, multi-layer mirror, plane mirror and small scale X-ray diode et al. Soft X-ray spectrometers built of multi-layer mirror-GaAs (with neutron irradiation), and plane mirror-small-scale XRD, and plane mirror-GaAs (with proton irradiation) are prepared. These spectrometers are examined in Shen Guang-II laser facility, and some external estimation are given. (authors)

  9. Small-Scale Shock Testing of Propellants and Ingredients

    National Research Council Canada - National Science Library

    Dawley, S

    2004-01-01

    .... The use of small-scale gap testing to evaluate the shock sensitivity of individual propellant ingredients and propellant formulations is a valuable method for experimentally establishing shock...

  10. Exergoeconomic analysis of small-scale biomass steam cogeneration

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Sotomonte, Cesar Adolfo; Lora, Electo Eduardo Silva [Universidade Federal de Itajuba, MG (Brazil)], e-mails: c.rodriguez32@unifei.edu.br, electo@unifei.edu.br; Venturini, Osvaldo Jose; Escobar, Jose Carlos [Universidad Federal de Itajuba, MG (Brazil)], e-mail: osvaldo@unifei.edu.br

    2010-07-01

    The principal objective of this work is to develop a calculation process, based on the second law of thermodynamics, for evaluating the thermoeconomic potential of a small steam cogeneration plant using waste from pulp processing and/or sawmills as fuel. Four different configurations are presented and assessed. The exergetic efficiency of the cycles that use condensing turbines is found to be around 11%, which has almost 3 percent higher efficiency than cycles with back pressure turbines. The thermoeconomic equations used in this paper estimated the production costs varying the fuel price. The main results show that present cost of technologies in a small-scale steam cycle cogeneration do not justify the implementation of more efficient systems for biomass prices less than 100 R$/t. (author)

  11. Small volume target for F-18 production

    Science.gov (United States)

    Pellicioli, M.; Schuler, J.; Marchand, P.; Brasse, D.

    2017-05-01

    In order to reduce the volume of O-18 enriched water used for each F-18 production for research a small volume target of 1 ml has been designed at IPHC. The designed is derived from ACSI 3.8ml F-18 target and uses both water and Helium cooling. After one year of use production yield is reported.

  12. Appraisal of Hygiene Indicators and Farming Practices in the Production of Leafy Vegetables by Organic Small-Scale Farmers in uMbumbulu (Rural KwaZulu-Natal, South Africa)

    Science.gov (United States)

    Mdluli, Fezile; Thamaga-Chitja, Joyce; Schmidt, Stefan

    2013-01-01

    During October, November and December 2011 (when highest sales of Agri-Hub fresh produce are observed), irrigation water, compost, lettuce and spinach sampled from four different farmer cooperatives supplying the local Agri-Hub in uMbumbulu (KwaZulu-Natal, South Africa) were analyzed monthly for the presence of total and fecal coliforms and Escherichia coli using the most probable number (MPN) technique. The pH values for all irrigation water samples analyzed were within the acceptable range of 6.5–8.5 for agricultural use. Fecal coliform levels were vegetables produced by Agri-Hub small-scale farmers met the requirements for total coliforms of vegetables were below the limit of detection. In addition, the farming practices of 73 farmers were assessed via a survey. The results revealed that more than 40% of farmers used microbiologically safe tap water for irrigation and that trained farmers have a significantly better understanding of the importance of production hygiene than untrained farmers. These results reiterate the importance of interventions that build capacity in the area of food safety and hygiene of small-scale farmers for market access of formal value chains. PMID:24065036

  13. Appraisal of hygiene indicators and farming practices in the production of leafy vegetables by organic small-scale farmers in uMbumbulu (Rural KwaZulu-Natal, South Africa).

    Science.gov (United States)

    Mdluli, Fezile; Thamaga-Chitja, Joyce; Schmidt, Stefan

    2013-09-13

    During October, November and December 2011 (when highest sales of Agri-Hub fresh produce are observed), irrigation water, compost, lettuce and spinach sampled from four different farmer cooperatives supplying the local Agri-Hub in uMbumbulu (KwaZulu-Natal, South Africa) were analyzed monthly for the presence of total and fecal coliforms and Escherichia coli using the most probable number (MPN) technique. The pH values for all irrigation water samples analyzed were within the acceptable range of 6.5-8.5 for agricultural use. Fecal coliform levels were vegetables produced by Agri-Hub small-scale farmers met the requirements for total coliforms of vegetables were below the limit of detection. In addition, the farming practices of 73 farmers were assessed via a survey. The results revealed that more than 40% of farmers used microbiologically safe tap water for irrigation and that trained farmers have a significantly better understanding of the importance of production hygiene than untrained farmers. These results reiterate the importance of interventions that build capacity in the area of food safety and hygiene of small-scale farmers for market access of formal value chains.

  14. Pilot study on arsenic removal from groundwater using a small-scale reverse osmosis system-Towards sustainable drinking water production.

    Science.gov (United States)

    Schmidt, Stefan-André; Gukelberger, Ephraim; Hermann, Mario; Fiedler, Florian; Großmann, Benjamin; Hoinkis, Jan; Ghosh, Ashok; Chatterjee, Debashis; Bundschuh, Jochen

    2016-11-15

    Arsenic contamination of groundwater is posing a serious challenge to drinking water supplies on a global scale. In India and Bangladesh, arsenic has caused the most serious public health issue in the world for nearly two decades. The aim of this work was to study an arsenic removal system based on reverse osmosis at pilot scale treating two different water sources from two different locations in the State of Bihar, India. For this purpose two villages, Bind Toli and Ramnagar in the Patna District were selected, both located very close to the river Ganga. The trials were conducted with aerated and non-aerated groundwater. It is the first time that the arsenic removal efficiency for aerated and non-aerated groundwater by reverse osmosis technology in combination with an energy-saving recovery system have been studied. As the principle of reverse osmosis requires a relatively high pressure, its energy demand is naturally high. By using an energy recovery system, this demand can be lowered, leading to an energy demand per liter permeate of 3-4Wh/L only. Due to high iron levels in the groundwater and as a consequence the precipitation of ferric (hydr)oxides, it was necessary to develop a granular media filter for the trials under aeration in order to protect the membrane from clogging. Two different materials, first locally available sand, and second commercially available anthracite were tested in the granular media filter. For the trials with aerated groundwater, total arsenic removal efficiency at both locations was around 99% and the arsenic concentration in permeate was in compliance with the WHO and National Indian Standard of 10μg/L. However, trials under anoxic conditions with non-aerated groundwater could not comply with this standard. Additionally a possible safe discharge of the reverse osmosis concentrate into an abandoned well was studied. It was observed that re-injection of reject water underground may offer a safe disposal option. However, long

  15. Small scale production of vegetal coal in the state of Amazonas, Brazil: legal and social-economical aspects; Producao de carvao vegetal em pequena escala no Amazonas: aspectos legais e socio-ambientais

    Energy Technology Data Exchange (ETDEWEB)

    Lima, Roberto Ferreira de; Souza, Rubem Cesar Rodrigues de [Amazonas Univ., Manaus, AM (Brazil). Nucleo de Eficiencia Energetica (NEFEN)]. E-mail: nefen_ua@objetivomao.br

    2000-07-01

    Being a form of cheap energy, abundant and accessible, the vegetable coal is quite often used generally in the urban and rural areas in the Amazonas state, domestic and commercial use as well. Several families live of the production activity and commercialization of vegetable coal inside the State of Amazonas. However, actions of government organs of the environment area turn more and more difficult the exercise of those activities, creating a situation of clandestine production and in some cases making unfeasible the only form of subsistence of several families. Besides the legal aspect there exist the low technological level, being the production of vegetable coal done in ovens of the type 'hot tail', which cause problems for the users health. The mentioned subjects are discussed in that work based on the study accomplished at three places producing the vegetable coal in the the State of Amazonas hinter side, in the proximities of Manaus. Through the information obtained in the communities a proposal is presented for the small scale production of vegetable coal in a economical, social and environmentally self sustainable way. (author)

  16. Scaling in small-world resistor networks

    International Nuclear Information System (INIS)

    Korniss, G.; Hastings, M.B.; Bassler, K.E.; Berryman, M.J.; Kozma, B.; Abbott, D.

    2006-01-01

    We study the effective resistance of small-world resistor networks. Utilizing recent analytic results for the propagator of the Edwards-Wilkinson process on small-world networks, we obtain the asymptotic behavior of the disorder-averaged two-point resistance in the large system-size limit. We find that the small-world structure suppresses large network resistances: both the average resistance and its standard deviation approaches a finite value in the large system-size limit for any non-zero density of random links. We also consider a scenario where the link conductance decays as a power of the length of the random links, l -α . In this case we find that the average effective system resistance diverges for any non-zero value of α

  17. The case for small-scale domestic cannabis cultivation.

    Science.gov (United States)

    Decorte, Tom

    2010-07-01

    The shift to (inter)regional production, trade and domestic cultivation has become an irreversible international trend. Until now, the focus of most empirical work has been on large-scale, commercially oriented and professionally organized segments of the cannabis industry, often based on police data and on the perspective of law enforcement agencies. This paper offers a review of recent Dutch-language research that focuses on cannabis cultivation. Empirical studies were identified through literature searches using relevant search terms and Web of Science, Elin, Social Science Research Network and Elsevier ScienceDirect. The paper presents the main findings of Dutch and Belgian empirical work on the factors that stimulated the import substitution process on the cannabis market, aspects related to quality and potency issues, typologies of cannabis growers, and (unintended) effects of pursued policies. In the light of this (selective) review the author offers some commentary and analysis concerning the claims made by different stakeholders, and concludes with some reflections on future research and on policy implications. The author outlines the importance of small-scale, independent or ideologically oriented cannabis cultivation as an under-researched market segment. The author also makes a case for greater toleration of small-scale cannabis cultivation, to secure the least worst of cannabis markets. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  18. Production of the {sup 14}C-labeled insecticidal protein Cry1Ab for soil metabolic studies using a recombinant Escherichia coli in small-scale batch fermentations

    Energy Technology Data Exchange (ETDEWEB)

    Valldor, Petra; Miethling-Graff, Rona; Dockhorn, Susanne; Martens, Rainer; Tebbe, Christoph C. [Federal Research Institute for Rural Areas, Forestry and Fisheries, Braunschweig (Germany). Thuenen Institute (vTI) for Biodiversity

    2012-10-15

    Insecticidal Cry proteins naturally produced by Bacillus thuringiensis are a major recombinant trait expressed by genetically modified crops. They are released into the soil during and after cropping. The objective of this study was to produce {sup 14}C-labeled Cry1Ab proteins for soil metabolic studies in scope of their environmental risk assessment. Cry1Ab was synthesized as a protoxin by Escherichia coli HB101 pMP in 200-mL liquid batch culture fermentations and purified from inclusion bodies after trypsin digestion. For cultivation, U-{sup 14}C-glycerol was the main carbon source. Inclusion bodies were smaller and Cry1Ab yield was lower when the initial amount of total organic carbon in the cultivation broth was below 6.4 mg C L{sup -1}. Concentrations of 12.6 g {sup 14}C-labeled glycerol L{sup -1} (1 % v/v) resulted in the production of 17.1 mg {sup 14}C-Cry1Ab L{sup -1} cultivation medium. {sup 14}C mass balances showed that approx. 50 % of the label was lost by respiration and 20 % remained in the growth media, while the residual activity was associated with biomass. Depending on the production batch, 0.01 to 0.05 % of the total {sup 14}C originated from Cry1Ab. In the presence of 2.04 MBq {sup 14}C-labeled carbon sources, a specific activity of up to 268 Bq mg{sup -1} {sup 14}C-Cry1Ab was obtained. A more than threefold higher specific activity was achieved with 4.63 MBq and an extended cultivation period of 144 h. This study demonstrates that {sup 14}C-labeled Cry1Ab can be obtained from batch fermentations with E. coli in the presence of a simple {sup 14}C-labeled carbon source. It also provides a general strategy to produce {sup 14}C-labeled proteins useful for soil metabolic studies. (orig.)

  19. Production of sake from rice material exposed to γ-radiation and technical development for its production. Characterization of low-dose exposed rice and small-scale brewing with it

    International Nuclear Information System (INIS)

    Samuta, Takashi; Aramaki, Isao; Hashizume, Katsumi

    1997-01-01

    The effects of γ-ray radiation have been studied on rice materials for sake production. Previous studies showed that the radiation caused to decrease the viscosity as well as the gelatinization heat of those rice and also decrease the chain length of amylose in its endosperm starch. Therefore, it is possible that a new kind sake with excellent quality might be produced by exposing raw material to radiation at an appropriate dose. Here, it was demonstrated that even a low-dose radiation with γ-ray may change various properties of rice including milling characteristics, water absorbing capacity, digestibility, viscosity etc. However, the characteristics as to fermentation were not affected so much and significant changes were observed only in the degree of coloring of the products. The effects of radiation on the constituents of sake were found to be comparatively small. For the production of matured sake, γ-ray radiation was evaluated to be much effective, because the period of maturation was significantly shortened by using irradiated rice material. Thus, a fragrant matured-like sake could be easily produced from γ-ray radiated rice. There remains a trouble in the coloring of the product. (M.N.)

  20. Comparison Between Overtopping Discharge in Small and Large Scale Models

    DEFF Research Database (Denmark)

    Helgason, Einar; Burcharth, Hans F.

    2006-01-01

    The present paper presents overtopping measurements from small scale model test performed at the Haudraulic & Coastal Engineering Laboratory, Aalborg University, Denmark and large scale model tests performed at the Largde Wave Channel,Hannover, Germany. Comparison between results obtained from...... small and large scale model tests show no clear evidence of scale effects for overtopping above a threshold value. In the large scale model no overtopping was measured for waveheights below Hs = 0.5m as the water sunk into the voids between the stones on the crest. For low overtopping scale effects...

  1. [Small scale direct oxide reduction (DOR) experiments

    International Nuclear Information System (INIS)

    1987-01-01

    Objectives were to provide process design information to the Plutonium Recovery Project and to produce DOR (direct oxide reduction) product which meets Foundry purity specifications and Oh-0 Foundry specifications

  2. Technical efficiency of small-scale fishing households in Tanzanian ...

    African Journals Online (AJOL)

    This paper examines the technical efficiency of Tanzanian small-scale fishing households, based on data from two coastal villages located near Bagamoyo and Zanzibar, using a stochastic frontier model with technical inefficiency. The estimated mean technical efficiency of small-scale fishing households was 52%, showing ...

  3. Transaction Cost Of Borrowing Among Small Scale Farmers In ...

    African Journals Online (AJOL)

    The study examined transaction cost of borrowing among small scale farmers in Rivers State, Nigeria. Data was collected with the aid of structured questionnaire from 109 randomly selected small scale farmers in the study area. Data analysis was by frequency, percentage and mean. It was found that farmers mostly ...

  4. Pair production in small angle Bhabha scattering

    International Nuclear Information System (INIS)

    Arbuzov, A.B.; Kuraev, Eh.A.; Merenkov, N.P.; Trentadue, L.

    1995-01-01

    The radiative corrections due to a pair production in the small angle high energy e + e - Bhabha scattering are considered. The corrections due to the production of virtual pairs as well as real soft and hard ones are calculated analytically. The collinear and semi-collinear kinematical regions of the hard pair production are taken into account. The results in the leading and next-to-leading logarithmic approximations provide the accuracy of Ο (0.1%). The results of numerical calculations show that the effects of pairs production are to be taken into account in the precise luminosity determination at LEP. 9 refs., 3 figs., 2 tabs

  5. Investigation of the feasibility of a small scale transmutation device

    Science.gov (United States)

    Sit, Roger Carson

    This dissertation presents the design and feasibility of a small-scale, fusion-based transmutation device incorporating a commercially available neutron generator. It also presents the design features necessary to optimize the device and render it practical for the transmutation of selected long-lived fission products and actinides. Four conceptual designs of a transmutation device were used to study the transformation of seven radionuclides: long-lived fission products (Tc-99 and I-129), short-lived fission products (Cs-137 and Sr-90), and selective actinides (Am-241, Pu-238, and Pu-239). These radionuclides were chosen because they are major components of spent nuclear fuel and also because they exist as legacy sources that are being stored pending a decision regarding their ultimate disposition. The four designs include the use of two different devices; a Deuterium-Deuterium (D-D) neutron generator (for one design) and a Deuterium-Tritium (D-T) neutron generator (for three designs) in configurations which provide different neutron energy spectra for targeting the radionuclide for transmutation. Key parameters analyzed include total fluence and flux requirements; transmutation effectiveness measured as irradiation effective half-life; and activation products generated along with their characteristics: activity, dose rate, decay, and ingestion and inhalation radiotoxicity. From this investigation, conclusions were drawn about the feasibility of the device, the design and technology enhancements that would be required to make transmutation practical, the most beneficial design for each radionuclide, the consequence of the transmutation, and radiation protection issues that are important for the conceptual design of the transmutation device. Key conclusions from this investigation include: (1) the transmutation of long-lived fission products and select actinides can be practical using a small-scale, fusion driven transmutation device; (2) the transmutation of long

  6. Small-scale fisheries bycatch jeopardizes endangered Pacific loggerhead turtles.

    Directory of Open Access Journals (Sweden)

    S Hoyt Peckham

    2007-10-01

    Full Text Available Although bycatch of industrial-scale fisheries can cause declines in migratory megafauna including seabirds, marine mammals, and sea turtles, the impacts of small-scale fisheries have been largely overlooked. Small-scale fisheries occur in coastal waters worldwide, employing over 99% of the world's 51 million fishers. New telemetry data reveal that migratory megafauna frequent coastal habitats well within the range of small-scale fisheries, potentially producing high bycatch. These fisheries occur primarily in developing nations, and their documentation and management are limited or non-existent, precluding evaluation of their impacts on non-target megafauna.30 North Pacific loggerhead turtles that we satellite-tracked from 1996-2005 ranged oceanwide, but juveniles spent 70% of their time at a high use area coincident with small-scale fisheries in Baja California Sur, Mexico (BCS. We assessed loggerhead bycatch mortality in this area by partnering with local fishers to 1 observe two small-scale fleets that operated closest to the high use area and 2 through shoreline surveys for discarded carcasses. Minimum annual bycatch mortality in just these two fleets at the high use area exceeded 1000 loggerheads year(-1, rivaling that of oceanwide industrial-scale fisheries, and threatening the persistence of this critically endangered population. As a result of fisher participation in this study and a bycatch awareness campaign, a consortium of local fishers and other citizens are working to eliminate their bycatch and to establish a national loggerhead refuge.Because of the overlap of ubiquitous small-scale fisheries with newly documented high-use areas in coastal waters worldwide, our case study suggests that small-scale fisheries may be among the greatest current threats to non-target megafauna. Future research is urgently needed to quantify small-scale fisheries bycatch worldwide. Localizing coastal high use areas and mitigating bycatch in

  7. Small-scale fisheries bycatch jeopardizes endangered Pacific loggerhead turtles.

    Science.gov (United States)

    Peckham, S Hoyt; Maldonado Diaz, David; Walli, Andreas; Ruiz, Georgita; Crowder, Larry B; Nichols, Wallace J

    2007-10-17

    Although bycatch of industrial-scale fisheries can cause declines in migratory megafauna including seabirds, marine mammals, and sea turtles, the impacts of small-scale fisheries have been largely overlooked. Small-scale fisheries occur in coastal waters worldwide, employing over 99% of the world's 51 million fishers. New telemetry data reveal that migratory megafauna frequent coastal habitats well within the range of small-scale fisheries, potentially producing high bycatch. These fisheries occur primarily in developing nations, and their documentation and management are limited or non-existent, precluding evaluation of their impacts on non-target megafauna. 30 North Pacific loggerhead turtles that we satellite-tracked from 1996-2005 ranged oceanwide, but juveniles spent 70% of their time at a high use area coincident with small-scale fisheries in Baja California Sur, Mexico (BCS). We assessed loggerhead bycatch mortality in this area by partnering with local fishers to 1) observe two small-scale fleets that operated closest to the high use area and 2) through shoreline surveys for discarded carcasses. Minimum annual bycatch mortality in just these two fleets at the high use area exceeded 1000 loggerheads year(-1), rivaling that of oceanwide industrial-scale fisheries, and threatening the persistence of this critically endangered population. As a result of fisher participation in this study and a bycatch awareness campaign, a consortium of local fishers and other citizens are working to eliminate their bycatch and to establish a national loggerhead refuge. Because of the overlap of ubiquitous small-scale fisheries with newly documented high-use areas in coastal waters worldwide, our case study suggests that small-scale fisheries may be among the greatest current threats to non-target megafauna. Future research is urgently needed to quantify small-scale fisheries bycatch worldwide. Localizing coastal high use areas and mitigating bycatch in partnership with small-scale

  8. Responsible and Sustainable Tourism : Strengthening Small-Scale ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Responsible and Sustainable Tourism : Strengthening Small-Scale ... to work with the Costa Rican association of small and medium tourism enterprises of the ... as the hub of a network of small service providers operating within the model. ... marketing and outreach, distance learning, and the integration of services that are ...

  9. Small-scale upgrading and refinement of biogas; Smaaskalig uppgradering och foeraedling av biogas

    Energy Technology Data Exchange (ETDEWEB)

    Blom, Helena; Mccann, Michael; Westman, Johan (Poeyry SwedPower AB, Stockholm (Sweden))

    2012-02-15

    Small-scale upgrading and refinement of biogas is a report which aims to compile the state of knowledge in small-scale biogas upgrading. The project have been a collaboration with Agrovaest and Energy Farm and was funded by the Foundation for Agricultural Research, Western Goetaland and the Agriculture Department. The technology available for small scale upgrade has been examined from the technical and economic standpoint. An economic comparison has been made and the production of upgraded biogas has been estimated for different raw gas flows. The work also contains information related to biogas production, upgrading and a comparison of liquid biogas, DME and Ecopar-diesel

  10. Dermatitis in small-scale metal industries

    Energy Technology Data Exchange (ETDEWEB)

    Coenraads, P J; Foo, S C; Phoon, W O; Lun, K C

    1985-03-01

    A survey in 21 small metal factories in Singapore revealed that 6.6% of 751 workers (530 male, 221 female) had a skin disorder on their hands and arms. Dermatitis accounted for 4.5% (34 cases) and follicular rashes for 1% (8 cases). Positive patch tests were found in 23% (8 cases) of those with dermatitis and in 9.8% (21 workers) of a control group without any skin problem. Dermatitis was found to be associated with exposure to solvents. Simultaneous analysis of various exposure/risk factors by multiple logistic regression indicated a significant effect of combined exposure to oils and solvents (interaction). Being over 35 years of age was also a significant risk factor, whereas the role of contact allergy, detected by patch testing, was less pronounced.

  11. Development of Production Control in Small Batch Production

    Directory of Open Access Journals (Sweden)

    Németh Péter

    2016-01-01

    Full Text Available Our aim with this paper is to develop a new performance measurement and control system for small batch production in the automotive industry. For this reason, we present our previous research results for warehouse performance measurement and adopt its methodology to production control. The proposed method is based on artificial intelligence (neural networks.

  12. A Guide to Bundling Small-scale CDM Projects

    International Nuclear Information System (INIS)

    Mariyappan, J.; Bhardwaj, N.; De Coninck, H.; Van der Linden, N.

    2005-07-01

    Small-scale renewable energy and energy efficiency projects that fit the development needs of many developing countries, can potentially be supported via the Clean Development Mechanism (CDM), one of the Kyoto Protocol's flexible mechanisms for tackling climate change. However, there is concern that due to high transaction costs, as well as many existing barriers, very few investments will be made in small-scale projects, which are often the most suitable development option in countries such as India. In view of this, the 'bundling' together of appropriate small-scale projects on a regional basis has been proposed as a way in which funding can be leveraged from international sources and transaction costs reduced. IT Power, IT Power India and the Energy research Centre of the Netherlands (ECN) are carrying out a 2-year project to establish the capacity within India to enable individual small scale projects to be bundled as a single CDM project. Overall objectives are to develop the necessary institutional capabilities to formulate and implement small scale CDM projects in India; to provide a guide on how to bundle small scale projects under the CDM in developing countries; and to raise the awareness of the potential for investment in small scale energy projects which can gain funding through the CDM

  13. The Hetex small-scale hydro plant

    International Nuclear Information System (INIS)

    Guentert, P.; Boller, F.; Wanner, A.

    2006-01-01

    This final report for the Swiss Federal Office of Energy (SFOE) takes a look at the 400 kW small hydroelectric power plant (SHP) installed on the Aabach stream in Niederlenz, Switzerland. With a maximum water-flow of 4.5 m 3 /s, the turbine can produce about 1.5 GWh of electricity per year. In spring 2005, bearing damage necessitated substantial renovation to the turbine and the generator. This study examines the state of the rest of the plant noted during maintenance work. It also focuses on the feeding of the electricity produced into the grid, the effects of increased residual water-flow, the option of using the Hallwilersee lake as a buffer, upstream flood evacuation and the possibility of green electricity certification. The calculation of the amount of water available is discussed. Due to inconsistent data, a corrected flow-duration curve was used. For the local river authorities, the through passage for fish from the Aare river up to the Hallwilersee has a high priority. The Hetex SHP weir is one of nine barriers to a direct connection. The planning of a fish-pass to be built in 2006 is discussed

  14. Small-scale eruptive filaments on the quiet sun

    International Nuclear Information System (INIS)

    Hermans, L.M.; Martin, S.F.

    1986-01-01

    A study of a little known class of eruptive events on the quiet sun was conducted. All of 61 small-scale eruptive filamentary structures were identified in a systematic survey of 32 days of H alpha time-lapse films of the quiet sun acquired at Big Bear Solar Observatory. When fully developed, these structures have an average length of 15 arc seconds before eruption. They appear to be the small-scale analog of large-scale eruptive filaments observed against the disk. At the observed rate of 1.9 small-scale eruptive features per field of view per average 7.0 hour day, the rate of occurence of these events on the sun were estimated to be greater than 600 per 24 hour day.. The average duration of the eruptive phase was 26 minutes while the average lifetime from formation through eruption was 70 minutes. A majority of the small-scale filamentary sturctures were spatially related to cancelling magnetic features in line-of-sight photospheric magnetograms. Similar to large-scale filaments, the small-scale filamentary structures sometimes divided opposite polarity cancelling fragments but often had one or both ends terminating at a cancellation site. Their high numbers appear to reflect the much greater flux on the quiet sun. From their characteristics, evolution, and relationship to photospheric magnetic flux, it was concluded that the structures described are small-scale eruptive filaments and are a subset of all filaments

  15. Models of Small-Scale Patchiness

    Science.gov (United States)

    McGillicuddy, D. J.

    2001-01-01

    Patchiness is perhaps the most salient characteristic of plankton populations in the ocean. The scale of this heterogeneity spans many orders of magnitude in its spatial extent, ranging from planetary down to microscale. It has been argued that patchiness plays a fundamental role in the functioning of marine ecosystems, insofar as the mean conditions may not reflect the environment to which organisms are adapted. Understanding the nature of this patchiness is thus one of the major challenges of oceanographic ecology. The patchiness problem is fundamentally one of physical-biological-chemical interactions. This interconnection arises from three basic sources: (1) ocean currents continually redistribute dissolved and suspended constituents by advection; (2) space-time fluctuations in the flows themselves impact biological and chemical processes, and (3) organisms are capable of directed motion through the water. This tripartite linkage poses a difficult challenge to understanding oceanic ecosystems: differentiation between the three sources of variability requires accurate assessment of property distributions in space and time, in addition to detailed knowledge of organismal repertoires and the processes by which ambient conditions control the rates of biological and chemical reactions. Various methods of observing the ocean tend to lie parallel to the axes of the space/time domain in which these physical-biological-chemical interactions take place. Given that a purely observational approach to the patchiness problem is not tractable with finite resources, the coupling of models with observations offers an alternative which provides a context for synthesis of sparse data with articulations of fundamental principles assumed to govern functionality of the system. In a sense, models can be used to fill the gaps in the space/time domain, yielding a framework for exploring the controls on spatially and temporally intermittent processes. The following discussion highlights

  16. Scale dependence and small x behaviour of polarized parton distributions

    CERN Document Server

    Ball, R D; Ridolfi, G; Forte, S; Ridolfi, G

    1995-01-01

    We discuss perturbative evolution of the polarized structure function g_1 in the (x,Q^2) plane, with special regard to the small-x region. We determine g_1 in terms of polarized quark and gluon distributions using coefficient functions to order alpha_s. At small x g_1 then displays substantial scale dependence, which necessarily implies a corresponding scale dependence in the large-x region. This scale dependence has significant consequences for the extraction of the first moment from the experimental data, reducing its value while increasing the error. Conversely, the scale dependence may be used to constrain the size of the polarized gluon distribution.

  17. A Small-Scale Low-Cost Gas Chromatograph

    Science.gov (United States)

    Gros, Natasa; Vrtacnik, Margareta

    2005-01-01

    The design and application of a small-scale portable gas chromatograph for learning of the basic concepts of chromatography is described. The apparatus consists of two basic separable units, which includes a chromatographic unit and an electronic unit.

  18. management and growth paradox of rural small-scale industrial

    African Journals Online (AJOL)

    User

    Keywords: Rural Small-Scale Industries, firm growth, management, proprietors, workforce ... veloping countries as a solution to the problem of scarcity .... In the analysis logistic regression sta- ..... of imported raw materials such as high cost and.

  19. Options for Sustaining Small and Medium Scale Enterprises in ...

    African Journals Online (AJOL)

    FIRST LADY

    problems in Nigeria due to numerous domestic and global economic problems, and policy ... national income till today remains low (Osamwonyi, 2009). For ... managers. Nwakoby (1988) defines Small and Medium-Scale business as “any.

  20. Strengthening industry-research linkage for small scale industrial ...

    African Journals Online (AJOL)

    Strengthening industry-research linkage for small scale industrial development in Ghana - the relevance of scientific and technological information. ... Journal of Applied Science and Technology. Journal Home · ABOUT · Advanced Search ...

  1. Financing small scale wind energy projects in the UK

    International Nuclear Information System (INIS)

    Mitchell, Catherine

    1993-01-01

    This paper shows how wind energy projects in the UK have obtained finance. It attempts to list the financing options open to small scale developments and to note any likely problems which may occur. (UK)

  2. The hazardous nature of small scale underground mining in Ghana

    Directory of Open Access Journals (Sweden)

    K.J. Bansah

    2016-01-01

    Full Text Available Small scale mining continues to contribute significantly to the growth of Ghana's economy. However, the sector poses serious dangers to human health and the environment. Ground failures resulting from poorly supported stopes have led to injuries and fatalities in recent times. Dust and fumes from drilling and blasting of ore present health threats due to poor ventilation. Four prominent small scale underground mines were studied to identify the safety issues associated with small scale underground mining in Ghana. It is recognized that small scale underground mining in Ghana is inundated with unsafe acts and conditions including stope collapse, improper choice of working tools, absence of personal protective equipment and land degradation. Inadequate monitoring of the operations and lack of regulatory enforcement by the Minerals Commission of Ghana are major contributing factors to the environmental, safety and national security issues of the operations.

  3. Mercury use in small scale gold mining in Ghana: an assessment of its impact on miners

    International Nuclear Information System (INIS)

    Biagya, Robert Yakubu

    2002-12-01

    Small scale gold mining is responsible for about 5% of Ghana’s annual gold production. It is estimated that between 80,000 and 100,000 people are engaged in small scale gold mining either on part-time or permanent basis. Amalgamation is the preferred method used by small scale gold miners for extracting free gold from its ores. The rate at which mercury, an important input in this method, is discharged into the atmosphere and water bodies is alarming. This research describes the various mining and processing methods in small scale gold mining and the extent of mercury use and releases to the environment. It discusses mercury and its human and environmental effects. It defines the various forms of mercury, routes of exposure, toxic effects. The levels of exposure to mercury by all groups of small scale gold miners are determined, and the impacts on the miners and the environment are assessed. It concludes that: • Mercury is mainly released into the environment as a result of small scale gold mining through spillage of elemental mercury and evaporation of mercury from the amalgam and sponge gold when they are heated on open fire. • Mercury in environmental samples from small scale gold mining areas is well above standard limit values. • Mercury released into the environment through small scale gold mining impacts negatively on the miners themselves and the general environment. Finally, it recommends the need for the adoption of mercury emission reduction strategies for dealing with the mercury problem. (au)

  4. Small-scale Aquaculture to Strengthen Food Security in Cambodia ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Small-scale Aquaculture to Strengthen Food Security in Cambodia (CIFSRF) ... for their families' consumption in the same ponds as large fish, which can be sold for income. ... The project also studies opportunities to scale up the model for broader use ... Assessing improvements in nutrition outcomes following agricultural ...

  5. Analysis of small-scale rotor hover performance data

    Science.gov (United States)

    Kitaplioglu, Cahit

    1990-01-01

    Rotor hover-performance data from a 1/6-scale helicopter rotor are analyzed and the data sets compared for the effects of ambient wind, test stand configuration, differing test facilities, and scaling. The data are also compared to full scale hover data. The data exhibited high scatter, not entirely due to ambient wind conditions. Effects of download on the test stand proved to be the most significant influence on the measured data. Small-scale data correlated resonably well with full scale data; the correlation did not improve with Reynolds number corrections.

  6. Fair trade for coffee producing small-scale farmers in Mexico

    Directory of Open Access Journals (Sweden)

    Nam kwon Mun

    2012-10-01

    Full Text Available The agriculture played an important role in the industrialization process of Mexico. However, the agricultural policy of State has isolated small scale farmers, giving priority just to large agricultural exporters. This study analyzes the implications that can have fair trade for the Mexican small scale farmers. The fair trade tries to cover the production cost and basic necessities for the small scale farmers, making direct ties between producers and consumers. This type of linkage guarantees the minimum price and the extra social payment to the small scale farmers, grouped in cooperatives o associations.Coffee is one of the most known fair trade product, and Mexico is one of the most important coffer exporters of the world. The fair trade of coffee production where many small farmers work is carried out by cooperative like UCIRI (Unión de Comunidades Indígenas de la Región Istmo. The case study shows that fair trade cannot provide complete answers to the all problems that have small farmers. But, since fair trade tries to promote small farmers well-being and many small farmers could get rid of extreme poverty thanks to fair trade, it might be possible to say that fair trade can be one valuable option for the sustainable development of small farmers.

  7. Small-scale soft-bodied robot with multimodal locomotion

    Science.gov (United States)

    Hu, Wenqi; Lum, Guo Zhan; Mastrangeli, Massimo; Sitti, Metin

    2018-02-01

    Untethered small-scale (from several millimetres down to a few micrometres in all dimensions) robots that can non-invasively access confined, enclosed spaces may enable applications in microfactories such as the construction of tissue scaffolds by robotic assembly, in bioengineering such as single-cell manipulation and biosensing, and in healthcare such as targeted drug delivery and minimally invasive surgery. Existing small-scale robots, however, have very limited mobility because they are unable to negotiate obstacles and changes in texture or material in unstructured environments. Of these small-scale robots, soft robots have greater potential to realize high mobility via multimodal locomotion, because such machines have higher degrees of freedom than their rigid counterparts. Here we demonstrate magneto-elastic soft millimetre-scale robots that can swim inside and on the surface of liquids, climb liquid menisci, roll and walk on solid surfaces, jump over obstacles, and crawl within narrow tunnels. These robots can transit reversibly between different liquid and solid terrains, as well as switch between locomotive modes. They can additionally execute pick-and-place and cargo-release tasks. We also present theoretical models to explain how the robots move. Like the large-scale robots that can be used to study locomotion, these soft small-scale robots could be used to study soft-bodied locomotion produced by small organisms.

  8. Validity of thermally-driven small-scale ventilated filling box models

    Science.gov (United States)

    Partridge, Jamie L.; Linden, P. F.

    2013-11-01

    The majority of previous work studying building ventilation flows at laboratory scale have used saline plumes in water. The production of buoyancy forces using salinity variations in water allows dynamic similarity between the small-scale models and the full-scale flows. However, in some situations, such as including the effects of non-adiabatic boundaries, the use of a thermal plume is desirable. The efficacy of using temperature differences to produce buoyancy-driven flows representing natural ventilation of a building in a small-scale model is examined here, with comparison between previous theoretical and new, heat-based, experiments.

  9. Small-scale dynamo at low magnetic Prandtl numbers

    Science.gov (United States)

    Schober, Jennifer; Schleicher, Dominik; Bovino, Stefano; Klessen, Ralf S.

    2012-12-01

    The present-day Universe is highly magnetized, even though the first magnetic seed fields were most probably extremely weak. To explain the growth of the magnetic field strength over many orders of magnitude, fast amplification processes need to operate. The most efficient mechanism known today is the small-scale dynamo, which converts turbulent kinetic energy into magnetic energy leading to an exponential growth of the magnetic field. The efficiency of the dynamo depends on the type of turbulence indicated by the slope of the turbulence spectrum v(ℓ)∝ℓϑ, where v(ℓ) is the eddy velocity at a scale ℓ. We explore turbulent spectra ranging from incompressible Kolmogorov turbulence with ϑ=1/3 to highly compressible Burgers turbulence with ϑ=1/2. In this work, we analyze the properties of the small-scale dynamo for low magnetic Prandtl numbers Pm, which denotes the ratio of the magnetic Reynolds number, Rm, to the hydrodynamical one, Re. We solve the Kazantsev equation, which describes the evolution of the small-scale magnetic field, using the WKB approximation. In the limit of low magnetic Prandtl numbers, the growth rate is proportional to Rm(1-ϑ)/(1+ϑ). We furthermore discuss the critical magnetic Reynolds number Rmcrit, which is required for small-scale dynamo action. The value of Rmcrit is roughly 100 for Kolmogorov turbulence and 2700 for Burgers. Furthermore, we discuss that Rmcrit provides a stronger constraint in the limit of low Pm than it does for large Pm. We conclude that the small-scale dynamo can operate in the regime of low magnetic Prandtl numbers if the magnetic Reynolds number is large enough. Thus, the magnetic field amplification on small scales can take place in a broad range of physical environments and amplify week magnetic seed fields on short time scales.

  10. Small-scale dynamo at low magnetic Prandtl numbers.

    Science.gov (United States)

    Schober, Jennifer; Schleicher, Dominik; Bovino, Stefano; Klessen, Ralf S

    2012-12-01

    The present-day Universe is highly magnetized, even though the first magnetic seed fields were most probably extremely weak. To explain the growth of the magnetic field strength over many orders of magnitude, fast amplification processes need to operate. The most efficient mechanism known today is the small-scale dynamo, which converts turbulent kinetic energy into magnetic energy leading to an exponential growth of the magnetic field. The efficiency of the dynamo depends on the type of turbulence indicated by the slope of the turbulence spectrum v(ℓ)∝ℓ^{ϑ}, where v(ℓ) is the eddy velocity at a scale ℓ. We explore turbulent spectra ranging from incompressible Kolmogorov turbulence with ϑ=1/3 to highly compressible Burgers turbulence with ϑ=1/2. In this work, we analyze the properties of the small-scale dynamo for low magnetic Prandtl numbers Pm, which denotes the ratio of the magnetic Reynolds number, Rm, to the hydrodynamical one, Re. We solve the Kazantsev equation, which describes the evolution of the small-scale magnetic field, using the WKB approximation. In the limit of low magnetic Prandtl numbers, the growth rate is proportional to Rm^{(1-ϑ)/(1+ϑ)}. We furthermore discuss the critical magnetic Reynolds number Rm_{crit}, which is required for small-scale dynamo action. The value of Rm_{crit} is roughly 100 for Kolmogorov turbulence and 2700 for Burgers. Furthermore, we discuss that Rm_{crit} provides a stronger constraint in the limit of low Pm than it does for large Pm. We conclude that the small-scale dynamo can operate in the regime of low magnetic Prandtl numbers if the magnetic Reynolds number is large enough. Thus, the magnetic field amplification on small scales can take place in a broad range of physical environments and amplify week magnetic seed fields on short time scales.

  11. Experimental, theoretical, and numerical studies of small scale combustion

    Science.gov (United States)

    Xu, Bo

    Recently, the demand increased for the development of microdevices such as microsatellites, microaerial vehicles, micro reactors, and micro power generators. To meet those demands the biggest challenge is obtaining stable and complete combustion at relatively small scale. To gain a fundamental understanding of small scale combustion in this thesis, thermal and kinetic coupling between the gas phase and the structure at meso and micro scales were theoretically, experimentally, and numerically studied; new stabilization and instability phenomena were identified; and new theories for the dynamic mechanisms of small scale combustion were developed. The reduction of thermal inertia at small scale significantly reduces the response time of the wall and leads to a strong flame-wall coupling and extension of burning limits. Mesoscale flame propagation and extinction in small quartz tubes were theoretically, experimentally and numerically studied. It was found that wall-flame interaction in mesoscale combustion led to two different flame regimes, a heat-loss dominant fast flame regime and a wall-flame coupling slow flame regime. The nonlinear transition between the two flame regimes was strongly dependent on the channel width and flow velocity. It is concluded that the existence of multiple flame regimes is an inherent phenomenon in mesoscale combustion. In addition, all practical combustors have variable channel width in the direction of flame propagation. Quasi-steady and unsteady propagations of methane and propane-air premixed flames in a mesoscale divergent channel were investigated experimentally and theoretically. The emphasis was the impact of variable cross-section area and the flame-wall coupling on the flame transition between different regimes and the onset of flame instability. For the first time, spinning flames were experimentally observed for both lean and rich methane and propane-air mixtures in a broad range of equivalence ratios. An effective Lewis number

  12. Small watershed-scale research and the challenges ahead

    Science.gov (United States)

    Larsen, M. C.; Glynn, P. D.

    2008-12-01

    For the past century, Federal mission science agencies (eg. USFS, NRCS, ARS, USGS) have had the long- term agency goals, infrastructure, and research staff to conduct research and data collection in small watersheds as well as support these activities for non-Federal partners. The National Science Foundation has been a strong partner with the Federal mission science agencies, through the LTER network, which is dependent on Federally supported research sites, and more recently with the emerging CUAHSI, WATERS, CZEN, and NEON initiatives. Much of the NSF-supported research builds on the foundations provided by their Federally supported partners, who sustain the long-term, extensive monitoring activity and research sites, including making long-term data available to all users via public interfaces. The future of these programs, and their enhancement/expansion to face the intensifying concurrent challenges of population growth, land-use change, and climate change, is dependent on a well-funded national commitment to basic science. Such a commitment will allow the scientific community to advance our understanding of these scientific challenges and to synthesize our understanding among research sites and at the national scale. Small watersheds serve as essential platforms where hypotheses can be tested, as sentinels for climate change, and as a basis for comparing and scaling up local information and syntheses to regional and continental scales. The science guides resource management and mitigation decisions and is fundamental to the development of predictive models. Furthermore, small-watershed research and monitoring programs are generally undervalued because many research questions that can be addressed now or in the future were not anticipated when the sites were initiated. Some examples include: 1) the quantification, characterization, and understanding of how emerging contaminants, personal care products, and endocrine disruptors affect organisms - substances that

  13. Small scale wood combustion in Germany. Recent research and trends

    Energy Technology Data Exchange (ETDEWEB)

    Maier, H.; Unterberger, S.; Hein, K.R.G. [Institute of Process Engineering and Power Plant Technology, University of Stuttgart (Germany)

    1998-12-31

    To reduce Europe`s greenhouse gas emission CO{sub 2} it is a challenging task utilising biomass fuels as there are wood or wood residues from the forest industry. The utilisation can be done either in commercially operated medium (> 50 kWth) or full scale (> 1 MWth) decentralised heat and power stations or in small scale (< 50 kWth) domestic heating systems. In small scale heating systems untreated wood logs, wood briquette or wood pellets and in few cases wood chips are used. The present market in Germany is focused on the use of wood logs. Presently, the use of wood pellets in small scale automatically operated boilers < 15 kW especially for low energy houses is discussed more and more. Since 1980 the installation of new wood fired small scale domestic heating systems reached a significant size due to the interest of the customers to have a alternative inhouse heating system and to increase the living comfort. In 1994 the amount of sold small scale heaters in Germany were in total about 133.258 units. The thermal power of in 1994 sold units is estimated of about 1350 MW which is a significant size in total with regard to domestic heating purposes. Since few years there is a clear market trend in Germany towards the installation of open fire stoves. Due to this trend in Germany and the design characteristic of open fire stoves using huge glass doors of glass windows it is very difficult to achieve a further reduction of emissions like CO and unburned volatile hydrocarbons (VOC). In the text the requirements for modern small scale wood fired stoves in Germany as well as the actual stage and trend of research and development (R and D) are discussed 4 refs.

  14. Engineering development for a small-scale recirculator experiment

    International Nuclear Information System (INIS)

    Newton, M.A.; Deadrick, F.J.; Hanks, R.L.; Hawkins, S.A.; Holm, K.A.; Kirbie, H.C.; Karpenko, V.P.; Nattrass, L.A.; Longinotti, D.B.

    1995-01-01

    Lawrence Livermore National Laboratory (LLNL) is evaluating the physics and technology of recirculating induction accelerators for heavy-ion inertial-fusion drivers. As part of this evaluation, the authors are building a small-scale recirculator to demonstrate the concept and to use as a test bed for the development of recirculator technologies. System designs have been completed and components are presently being designed and developed for the small-scale recirculator. This paper discusses results of the design and development activities that are presently being conducted to implement the small-scale recirculator experiments. An, overview of the system design is presented along with a discussion of the implications of this design on the mechanical and electrical hardware. The paper focuses primarily on discussions of the development and design of the half-lattice period hardware and the advanced solid-state modulator

  15. Airfoil optimization for noise emission problem on small scale turbines

    Energy Technology Data Exchange (ETDEWEB)

    Gocmen, Tuhfe; Ozerdem, Baris [Mechanical Engineering Department, Yzmir Institute of Technology (Turkey)

    2011-07-01

    Wind power is a preferred natural resource and has had benefits for the energy industry and for the environment all over the world. However, noise emission from wind turbines is becoming a major concern today. This study paid close attention to small scale wind turbines close to urban areas and proposes an optimum number of six airfoils to address noise emission concerns and performance criteria. The optimization process aimed to decrease the noise emission levels and enhance the aerodynamic performance of a small scale wind turbine. This study determined the sources and the operating conditions of broadband noise emissions. A new design is presented which enhances aerodynamic performance and at the same time reduces airfoil self noise. It used popular aerodynamic functions and codes based on aero-acoustic empirical models. Through numerical computations and analyses, it is possible to derive useful improvements that can be made to commercial airfoils for small scale wind turbines.

  16. CO2-impacts of a small-scale consumers levy

    International Nuclear Information System (INIS)

    1995-02-01

    Because of a number of developments (altered budgets of Dutch ministries and implementation of environmental policy plans of energy distribution companies in the Netherlands) the 1993 analyses of the effects of a small-scale consumer levy on the emission of CO 2 are updated. First, attention is paid to the conservation impetus as a result of an increase of the energy price for small-scale consumers. Next, the effects that can occur as a consequence of the presently suggested form of the levy (in particular, the exemption of renewable energy and waste heat) are discussed. Subsequently, the alterations of other policy tools, that are necessary in case a higher effectiveness of conservation measures is realized, are dealt with. The direct effect of a higher energy price on the saving behavior of the small-scale consumers is calculated by means of the CENECA-model. 4 tabs., 1 appendix, 8 refs

  17. Still Another Book of Small-Scale Motets

    OpenAIRE

    Rodríguez-Garcia, Esperanza

    2016-01-01

    UID/EAT/00693/2013 PTDC/CPC-MMU/0314/2014 ‘Still another book of small-scale motets: Sebastián Raval’s Motecta (1600)’ Lodovico Viadana’s Cento concerti ecclesiastici (Venice: Giacomo Vincenti, 1602), a collection of small-scale motets with basso continuo, is still considered ‘chronologically the first publication to include a basso continuo with sacred vocal music’. It has become the epitome of the advent of the Baroque in Italian sacred music. But, as has been argued in recent times, ...

  18. Design and Modelling of Small Scale Low Temperature Power Cycles

    DEFF Research Database (Denmark)

    Wronski, Jorrit

    he work presented in this report contributes to the state of the art within design and modelling of small scale low temperature power cycles. The study is divided into three main parts: (i) fluid property evaluation, (ii) expansion device investigations and (iii) heat exchanger performance......-oriented Modelica code and was included in the thermo Cycle framework for small scale ORC systems. Special attention was paid to the valve system and a control method for variable expansion ratios was introduced based on a cogeneration scenario. Admission control based on evaporator and condenser conditions...

  19. The scale of biomass production in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Matsumura, Yukihiko [School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashihiroshima-shi 739-8527 (Japan); Inoue, Takashi; Fukuda, Katsura [Global Warming Research Department, Mitsubishi Research Institute, Inc., 2-3-6 Ohtemachi, Chiyoda-ku, Tokyo 100-8141 (Japan); Komoto, Keiichi; Hada, Kenichiro [Renewable energy Team, Environment, Natural Resources and Energy Division, Mizuho Information and Research Institute, Inc., 2-3 Kanda-nishikicho, Chiyoda-ku, Tokyo 101-8443 (Japan); Hirata, Satoshi [Technical Institute, Kawasaki Heavy Industries, Ltd., 1-1 Kawasakicho, Akashi-shi, Hyogo 673-8666 (Japan); Minowa, Tomoaki [Biomass Recycle Research Laboratory, National Institute of Advanced and Industrial Science and Technology, 2-2-2 Hiro, Suehiro, Kure-shi, Hiroshima 737-0197 (Japan); Yamamoto, Hiromi [Socioeconomic Research Center, Central Research Institute of Electric Power Industry, 1-6-1 Ohtemachi, Chiyoda-ku, Tokyo 100-8126 (Japan)

    2005-11-01

    Policymakers working to introduce and promote the use of bioenergy in Japan require detailed information on the scales of the different types of biomass resources generated. In this research, the first of its type in Japan, the investigators reviewed various statistical resources to quantify the scale distribution of forest residues, waste wood from manufacturing, waste wood from construction, cattle manure, sewage sludge, night soil, household garbage, and waste food oil. As a result, the scale of biomass generation in Japan was found to be relatively small, on the average is no more than several tons in dry weight per day. (author)

  20. Fractal properties and small-scale structure of cosmic string networks

    International Nuclear Information System (INIS)

    Martins, C.J.A.P.; Shellard, E.P.S.

    2006-01-01

    We present results from a detailed numerical study of the small-scale and loop production properties of cosmic string networks, based on the largest and highest resolution string simulations to date. We investigate the nontrivial fractal properties of cosmic strings, in particular, the fractal dimension and renormalized string mass per unit length, and we also study velocity correlations. We demonstrate important differences between string networks in flat (Minkowski) spacetime and the two very similar expanding cases. For high resolution matter era network simulations, we provide strong evidence that small-scale structure has converged to 'scaling' on all dynamical length scales, without the need for other radiative damping mechanisms. We also discuss preliminary evidence that the dominant loop production size is also approaching scaling

  1. Macroscopic High-Temperature Structural Analysis Model of Small-Scale PCHE Prototype (II)

    International Nuclear Information System (INIS)

    Song, Kee Nam; Lee, Heong Yeon; Hong, Sung Deok; Park, Hong Yoon

    2011-01-01

    The IHX (intermediate heat exchanger) of a VHTR (very high-temperature reactor) is a core component that transfers the high heat generated by the VHTR at 950 .deg. C to a hydrogen production plant. Korea Atomic Energy Research Institute manufactured a small-scale prototype of a PCHE (printed circuit heat exchanger) that was being considered as a candidate for the IHX. In this study, as a part of high-temperature structural integrity evaluation of the small-scale PCHE prototype, we carried out high-temperature structural analysis modeling and macroscopic thermal and elastic structural analysis for the small-scale PCHE prototype under small-scale gas-loop test conditions. The modeling and analysis were performed as a precedent study prior to the performance test in the small-scale gas loop. The results obtained in this study will be compared with the test results for the small-scale PCHE. Moreover, these results will be used in the design of a medium-scale PCHE prototype

  2. Small-Scale Helicopter Automatic Autorotation : Modeling, Guidance, and Control

    NARCIS (Netherlands)

    Taamallah, S.

    2015-01-01

    Our research objective consists in developing a, model-based, automatic safety recovery system, for a small-scale helicopter Unmanned Aerial Vehicle (UAV) in autorotation, i.e. an engine OFF flight condition, that safely flies and lands the helicopter to a pre-specified ground location. In pursuit

  3. Nitrate-nitrogen removal with small-scale reverse osmosis ...

    African Journals Online (AJOL)

    The nitrate-nitrogen concentration in water supplied to clinics in Limpopo Province is too high to be fit for human consumption (35 to 75 mg/ℓ NO3-N). Therefore, small-scale technologies (reverse osmosis, ion-exchange and electrodialysis) were evaluated for nitrate-nitrogen removal to make the water potable (< 10 mg/ℓ ...

  4. Risk management strategies utilized by small scale poultry farmers ...

    African Journals Online (AJOL)

    Birds can only tolerate narrow temperature changes; therefore, poultry flocks are vulnerable to climate induced risk. This study investigated risk management strategies utilized by small scale poultry farmers in Oyo state. A total of 118 respondents were sampled using multi stage sampling procedure. Interview schedule was ...

  5. Effects of artisanal small-scale gold mining on fisheries ...

    African Journals Online (AJOL)

    Artisanal Small-scale Gold Mining (ASGM) has direct and indirect impacts on fisheries management. These impacts are mainly about the quality of the water where fish lives, ownership of the surrounding waters, land and human health. This study was carried out in two landing sites of Wagusu and Riskis Kogwari in ...

  6. Climate change adaptation strategies by small-scale farmers in ...

    African Journals Online (AJOL)

    Mburu

    SPSS) ... were financial constraints (93.4%), lack of relevant skills (74.5%) and lack of ... Key words: Climate change, small-scale farmers, adaptation strategies. ... investment in irrigation infrastructure, high post-harvest ..... 72.0 School drop out.

  7. New perspectives in small-scale fisheries management: challenges ...

    African Journals Online (AJOL)

    This is in response to the recognition that conventional fisheries management is not equipped to deal with the complexities, uncertainties and challenges prevalent in small-scale fishery systems. Consequently, a new fisheries paradigm is emerging based on the principles and ideas underpinning systems thinking, ...

  8. Development and utilization of spring water in small scale supply ...

    African Journals Online (AJOL)

    Development and utilization of spring water in small scale supply scheme for the Kogi State Polytechnic, Lokoja, central Nigeria. Joseph Omada. Abstract. No Abstract. Journal of Mining and Geology 2005, Vol. 41(1): 131-135. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL ...

  9. Agricultural Credit Utilization among Small Scale Women Farmers in ...

    African Journals Online (AJOL)

    ... monitor regularly the disbursement of agricultural loan to women farmers at the appropriate planning season with reasonable interest charge and that extension agents should ensure that the loan is utilized for only agricultural purposes. Key words: Credit utilization, small-scale farmer's income generation, Niger State.

  10. Lessons from Small-scale Standardised Testing of English Reading ...

    African Journals Online (AJOL)

    The superior performance by the public school can partly be explained by teachers teaching experience, most of them have been teaching for more than ten years and greater community support for the school. It is recommended that data produced through small-scale standardised testing should be used by school ...

  11. Work related injuries and associated factors among small scale ...

    African Journals Online (AJOL)

    Objective: This study aims to assess the magnitude of work related injury and associated factors among small scale industrial workers in Mizan-Aman town, Bench Maji Zone, Southwest Ethiopia. Method: A cross-sectional study design was conducted from February to May, 2016. Data was collected using a structured face to ...

  12. Role of Cooperatives in Small and Medium Scale Enterprises (SMEs ...

    African Journals Online (AJOL)

    The paper examined the contributions of cooperatives to small and medium scale enterprises (SME) development, identified the challenges and to suggested ways of strengthening this role. The paper argued that SMEs are the key to Nigeria‟s prosperity, but that past efforts by the government to promote SMEs has not ...

  13. The small-scale spatial distribution of an invading moth

    DEFF Research Database (Denmark)

    Nash, David Richard; Agassiz, David J. L.; Godfray, H. C. J.

    1995-01-01

    We studied the spread of a small leaf-mining moth [Phyllonorycter leucographella (Zeller), Gracillariidae] after its accidental introduction into the British Isles. At large geographical scales, previous work had shown the spread to be well described by a travelling wave of constant velocity. Her...

  14. Development of small-scale fisheries in Yemen: An exploration

    NARCIS (Netherlands)

    Wagenaar, A.; Haese, D' M.F.C.

    2007-01-01

    Yemen is one of the poorest countries in the world. The development of its fishery sector is increasingly being mentioned as a source of livelihood creation. The aims of this paper are to: (a) provide an overview of the institutional environment in which small-scale fishermen in Yemen operate; (b)

  15. Smoke emissions in small-scale burning of wood

    International Nuclear Information System (INIS)

    Tuomi, S.

    1993-01-01

    The article is based on research carried out in Finland and Sweden on the subject of emissions of smoke in the small-scale burning of wood and the factors affecting it. Due to incomplete combustion, small-scale burning of wood is particularly typified by its emissions of solid particles, carbon monoxide, hydrocarbons and PAH compounds. Included among factors influencing the volume of emissions are the load imposed on the heating device, the manner in which the fuel is fed into the firebox, fuel quality, and heating device structure. Emissions have been found to be at their minimum in connection with heating systems based on accumulators. Emissions can be significantly reduced by employing state-of-the-art technology, appropriate ways of heating and by dry fuel. A six-year bioenergy research programme was launched early in 1993 in Finland. All leading research institutions and enterprises participate in this programme. Reduction of emissions has been set as the central goal in the part dealing with small-scale burning of wood. Application of catalytic combustion in Finnish-made heating devices is one of the programmes development targets. Up to this date, the emissions produced in the small-scale burning of wood are not mentioned in official regulations pertaining to approved heating devices. In Sweden tar emissions are applied as a measure of the environmental impact imposed by heating devices

  16. A feasibility and implementation model of small-scale hydropower ...

    African Journals Online (AJOL)

    Large numbers of households and communities will not be connected to the national electricity grid for the foreseeable future due to high cost of transmission and distribution systems to remote communities and the relatively low electricity demand within rural communities. Small-scale hydropower used to play a very ...

  17. The Role of Small and Medium Scale Enterprises in Poverty ...

    African Journals Online (AJOL)

    It is aimed at finding out the extent to which small and medium scale enterprises, through their employment activities, helped to address poverty reduction. In trying to establish the thrust of the paper we used secondary data and the adoption of econometric model, specifically simple linear regression, to empirically explain ...

  18. Scaling and percolation in the small-world network model

    Energy Technology Data Exchange (ETDEWEB)

    Newman, M. E. J. [Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, New Mexico 87501 (United States); Watts, D. J. [Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, New Mexico 87501 (United States)

    1999-12-01

    In this paper we study the small-world network model of Watts and Strogatz, which mimics some aspects of the structure of networks of social interactions. We argue that there is one nontrivial length-scale in the model, analogous to the correlation length in other systems, which is well-defined in the limit of infinite system size and which diverges continuously as the randomness in the network tends to zero, giving a normal critical point in this limit. This length-scale governs the crossover from large- to small-world behavior in the model, as well as the number of vertices in a neighborhood of given radius on the network. We derive the value of the single critical exponent controlling behavior in the critical region and the finite size scaling form for the average vertex-vertex distance on the network, and, using series expansion and Pade approximants, find an approximate analytic form for the scaling function. We calculate the effective dimension of small-world graphs and show that this dimension varies as a function of the length-scale on which it is measured, in a manner reminiscent of multifractals. We also study the problem of site percolation on small-world networks as a simple model of disease propagation, and derive an approximate expression for the percolation probability at which a giant component of connected vertices first forms (in epidemiological terms, the point at which an epidemic occurs). The typical cluster radius satisfies the expected finite size scaling form with a cluster size exponent close to that for a random graph. All our analytic results are confirmed by extensive numerical simulations of the model. (c) 1999 The American Physical Society.

  19. Scaling and percolation in the small-world network model

    International Nuclear Information System (INIS)

    Newman, M. E. J.; Watts, D. J.

    1999-01-01

    In this paper we study the small-world network model of Watts and Strogatz, which mimics some aspects of the structure of networks of social interactions. We argue that there is one nontrivial length-scale in the model, analogous to the correlation length in other systems, which is well-defined in the limit of infinite system size and which diverges continuously as the randomness in the network tends to zero, giving a normal critical point in this limit. This length-scale governs the crossover from large- to small-world behavior in the model, as well as the number of vertices in a neighborhood of given radius on the network. We derive the value of the single critical exponent controlling behavior in the critical region and the finite size scaling form for the average vertex-vertex distance on the network, and, using series expansion and Pade approximants, find an approximate analytic form for the scaling function. We calculate the effective dimension of small-world graphs and show that this dimension varies as a function of the length-scale on which it is measured, in a manner reminiscent of multifractals. We also study the problem of site percolation on small-world networks as a simple model of disease propagation, and derive an approximate expression for the percolation probability at which a giant component of connected vertices first forms (in epidemiological terms, the point at which an epidemic occurs). The typical cluster radius satisfies the expected finite size scaling form with a cluster size exponent close to that for a random graph. All our analytic results are confirmed by extensive numerical simulations of the model. (c) 1999 The American Physical Society

  20. Optimisation of a cheap and residential small-scale production of edible crickets with local by-products as an alternative protein-rich human food source in Ratanakiri Province, Cambodia.

    Science.gov (United States)

    Caparros Megido, Rudy; Alabi, Taofic; Nieus, Clément; Blecker, Christophe; Danthine, Sabine; Bogaert, Jan; Haubruge, Éric; Francis, Frédéric

    2016-01-30

    The health status of the indigenous people of Ratanakiri Province, Cambodia, is significantly lower compared with that of the rest of the nation. The domestication and mass production of insects may represent a sustainable, cost effective and high quality alternative source of protein to traditional livestock. This study aimed to optimise a cheap and residential cricket breeding system based on unused wild resources. The development of crickets, Teleogryllus testaceus (Walker), under seven diets composed of taro aerial parts, young cassava leaves, young cashew leaves and brown rice flour (with or without banana slices), versus a traditionally used broiler feed diet was studied. Cricket mortality was low in all diets, except the two cashew-based diets. Total biomass was significantly higher under the broiler feed, in addition to the two diets containing a combination of cassava leaf powder and brown rice. Yet, crickets fed with the taro diet had the highest percentage of protein. Concerning the breeding system cost, units using cassava leaves were the cheapest. Diets based on cassava leaves seem to be the most promising. Nevertheless, to produce crickets with a high body mass and a high protein level, a new experiments must be devised in which cassava leaf maturity will be adapted to fit with the cricket growth stage. Moreover, to reduce the cost of the breeding units, handmade local products should be used instead of purchased components. © 2015 Society of Chemical Industry.

  1. Market-Oriented Product Innovation in Small Firms

    NARCIS (Netherlands)

    Verhees, F.J.H.M.

    2005-01-01

    Description: This thesis deals with product-innovation in small firms. It aims at a better understanding of the determinants of product innovation in small firms, particularly those determinants that are related to the market orientation of small firms. The focus of the study is on small firms that

  2. Thermodynamic modeling of small scale biomass gasifiers: Development and assessment of the ''Multi-Box'' approach.

    Science.gov (United States)

    Vakalis, Stergios; Patuzzi, Francesco; Baratieri, Marco

    2016-04-01

    Modeling can be a powerful tool for designing and optimizing gasification systems. Modeling applications for small scale/fixed bed biomass gasifiers have been interesting due to their increased commercial practices. Fixed bed gasifiers are characterized by a wide range of operational conditions and are multi-zoned processes. The reactants are distributed in different phases and the products from each zone influence the following process steps and thus the composition of the final products. The present study aims to improve the conventional 'Black-Box' thermodynamic modeling by means of developing multiple intermediate 'boxes' that calculate two phase (solid-vapor) equilibriums in small scale gasifiers. Therefore the model is named ''Multi-Box''. Experimental data from a small scale gasifier have been used for the validation of the model. The returned results are significantly closer with the actual case study measurements in comparison to single-stage thermodynamic modeling. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Is small beautiful? A multicriteria assessment of small-scale energy technology applications in local governments

    International Nuclear Information System (INIS)

    Burton, Jonathan; Hubacek, Klaus

    2007-01-01

    In its 2003 White Paper the UK government set ambitious renewable energy targets. Local governments and households have an increasing role in the overall energy system as consumers, suppliers of smaller-scale applications and citizens discussing energy projects. In this paper, we consider if small-scale or large-scale approaches to renewable energy provision can achieve energy targets in the most socially, economically and environmentally (SEE) effective way. We take a local case study of renewable energy provision in the Metropolitan Borough of Kirklees in Yorkshire, UK, and apply a multi-criteria decision analysis methodology to compare the small-scale schemes implemented in Kirklees with large-scale alternatives. The results indicate that small-scale schemes are the most SEE effective, despite large-scale schemes being more financially viable. The selection of the criteria on which the alternatives are assessed and the assigned weights for each criterion are of crucial importance. It is thus very important to include the relevant stakeholders to elicit this information

  4. Experimental investigation of small-scale gasification of woody biomass

    Energy Technology Data Exchange (ETDEWEB)

    Barrio, Maria

    2002-05-01

    A small-scale stratified down draft gasifier has been built and operated under stable conditions using wood pellets as fuel and air as gasification agent. The problems observed during the preliminary experiments have been described and explained; they are mainly related to the stability of the process. The stable operation of the gasifier has been characterised by the gas composition and the product gas tar and particle content. The biomass feeding rate has varied between 4,5 and 6,5 kg/h. The CO content of the product gas (23-26 % vol.) is higher than in similar gasifiers and the H{sub 2} content has been found to vary between 14 and 16 % vol. The tar content in the product gas (Ca. 3 g/Nm{sup 3}) is rather high compared with similar gasifiers. The temperature profile, together with other relevant parameters like the air-excess ratio, the air to fuel ratio and gas to fuel ratio have been calculated. The experiments show that the air excess ratio is rather constant, varying between 0,25 and 0,3. Experiments have been conducted with a gas engine using mixtures of CH{sub 4}, CO, H{sub 2}, CO{sub 2} and N{sub 2} as a fuel. NO{sub x} and CO emissions are analysed. The char gasification process has been studied in detail by means of Thermogravimetric Analysis. The study comprises the chemical kinetics of the gasification reactions of wood char in CO{sub 2} and H{sub 2}O, including the inhibition effect of CO and H{sub 2}. A kinetic model based on Langmuir-Hinshelwood kinetics has been found which relates the mass loss rate to the temperature, gas composition and degree of conversion for each reaction. The ratio CO/CO{sub 2} has been found to be a relevant parameter for reactivity. The gasification experiments in mixtures of CO{sub 2} and H{sub 2}O give reasons to believe that the rate of desorption for the complex C(O) varies depending on the gas mixture surrounding the char. It has been found that if the experimental data are obtained from separate H{sub 2}O/N{sub 2

  5. Impact of small-scale structures on estuarine circulation

    Science.gov (United States)

    Liu, Zhuo; Zhang, Yinglong J.; Wang, Harry V.; Huang, Hai; Wang, Zhengui; Ye, Fei; Sisson, Mac

    2018-05-01

    We present a novel and challenging application of a 3D estuary-shelf model to the study of the collective impact of many small-scale structures (bridge pilings of 1 m × 2 m in size) on larger-scale circulation in a tributary (James River) of Chesapeake Bay. We first demonstrate that the model is capable of effectively transitioning grid resolution from 400 m down to 1 m near the pilings without introducing undue numerical artifact. We then show that despite their small sizes and collectively small area as compared to the total channel cross-sectional area, the pilings exert a noticeable impact on the large-scale circulation, and also create a rich structure of vortices and wakes around the pilings. As a result, the water quality and local sedimentation patterns near the bridge piling area are likely to be affected as well. However, when evaluating over the entire waterbody of the project area, the near field effects are weighed with the areal percentage which is small compared to that for the larger unaffected area, and therefore the impact on the lower James River as a whole becomes relatively insignificant. The study highlights the importance of the use of high resolution in assessing the near-field impact of structures.

  6. Ethanol production in small- to medium-size facilities

    Science.gov (United States)

    Hiler, E. A.; Coble, C. G.; Oneal, H. P.; Sweeten, J. M.; Reidenbach, V. G.; Schelling, G. T.; Lawhon, J. T.; Kay, R. D.; Lepori, W. A.; Aldred, W. H.

    1982-04-01

    In early 1980 system design criteria were developed for a small-scale ethanol production plant. The plant was eventually installed on November 1, 1980. It has a production capacity of 30 liters per hour; this can be increased easily (if desired) to 60 liters per hour with additional fermentation tanks. Sixty-six test runs were conducted to date in the alcohol production facility. Feedstocks evaluated in these tests include: corn (28 runs); grain sorghum (33 runs); grain sorghum grits (1 run); half corn/half sorghum (1 run); and sugarcane juice (3 runs). In addition, a small bench-scale fermentation and distillation system was used to evaluate sugarcane and sweet sorghum feedstocks prior to their evaluation in the larger unit. In each of these tests, evaluation of the following items was conducted: preprocessing requirements; operational problems; conversion efficiency (for example, liters of alcohol produced per kilogram of feedstock); energy balance and efficiency; nutritional recovery from stillage; solids separation by screw press; chemical characterization of stillage including liquid and solids fractions; wastewater requirements; and air pollution potential.

  7. Higgs-boson production at small transverse momentum

    Science.gov (United States)

    Becher, Thomas; Neubert, Matthias; Wilhelm, Daniel

    2013-05-01

    Using methods from effective field theory, we have recently developed a novel, systematic framework for the calculation of the cross sections for electroweak gauge-boson production at small and very small transverse momentum q T , in which large logarithms of the scale ratio m V / q T are resummed to all orders. This formalism is applied to the production of Higgs bosons in gluon fusion at the LHC. The production cross section receives logarithmically enhanced corrections from two sources: the running of the hard matching coefficient and the collinear factorization anomaly. The anomaly leads to the dynamical generation of a non-perturbative scale {q_{*}}tilde{mkern6mu} {m_H}{e^{{{{{-const}} / {{{α_s}( {{m_H}} )}} .}}}}≈ 8 GeV, which protects the process from receiving large long-distance hadronic contributions. We present numerical predictions for the transverse-momentum spectrum of Higgs bosons produced at the LHC, finding that it is quite insensitive to hadronic effects.

  8. Robust, small-scale cultivation platform for Streptomyces coelicolor

    DEFF Research Database (Denmark)

    Sohoni, Sujata Vijay; Bapat, Prashant Madhusudan; Lantz, Anna Eliasson

    2012-01-01

    rates of antibiotics. CONCLUSION: We observed good agreement of the physiological data obtained in the developed MTP platform with bench-scale. Hence, the described MTP-based screening platform has a high potential for investigation of secondary metabolite biosynthesis in Streptomycetes and other....... The MTP cultivations were found to behave similar to bench-scale in terms of growth rate, productivity and substrate uptake rate and so was the onset of antibiotic synthesis. Shake flask cultivations however, showed discrepancy with respect to morphology and had considerably reduced volumetric production...

  9. Biomedical device prototype based on small scale hydrodynamic cavitation

    Directory of Open Access Journals (Sweden)

    Morteza Ghorbani

    2018-03-01

    Full Text Available This study presents a biomedical device prototype based on small scale hydrodynamic cavitation. The application of small scale hydrodynamic cavitation and its integration to a biomedical device prototype is offered as an important alternative to other techniques, such as ultrasound therapy, and thus constitutes a local, cheap, and energy-efficient solution, for urinary stone therapy and abnormal tissue ablation (e.g., benign prostate hyperplasia (BPH. The destructive nature of bubbly, cavitating, flows was exploited, and the potential of the prototype was assessed and characterized. Bubbles generated in a small flow restrictive element (micro-orifice based on hydrodynamic cavitation were utilized for this purpose. The small bubbly, cavitating, flow generator (micro-orifice was fitted to a small flexible probe, which was actuated with a micromanipulator using fine control. This probe also houses an imaging device for visualization so that the emerging cavitating flow could be locally targeted to the desired spot. In this study, the feasibility of this alternative treatment method and its integration to a device prototype were successfully accomplished.

  10. Biomedical device prototype based on small scale hydrodynamic cavitation

    Science.gov (United States)

    Ghorbani, Morteza; Sozer, Canberk; Alcan, Gokhan; Unel, Mustafa; Ekici, Sinan; Uvet, Huseyin; Koşar, Ali

    2018-03-01

    This study presents a biomedical device prototype based on small scale hydrodynamic cavitation. The application of small scale hydrodynamic cavitation and its integration to a biomedical device prototype is offered as an important alternative to other techniques, such as ultrasound therapy, and thus constitutes a local, cheap, and energy-efficient solution, for urinary stone therapy and abnormal tissue ablation (e.g., benign prostate hyperplasia (BPH)). The destructive nature of bubbly, cavitating, flows was exploited, and the potential of the prototype was assessed and characterized. Bubbles generated in a small flow restrictive element (micro-orifice) based on hydrodynamic cavitation were utilized for this purpose. The small bubbly, cavitating, flow generator (micro-orifice) was fitted to a small flexible probe, which was actuated with a micromanipulator using fine control. This probe also houses an imaging device for visualization so that the emerging cavitating flow could be locally targeted to the desired spot. In this study, the feasibility of this alternative treatment method and its integration to a device prototype were successfully accomplished.

  11. Small signal gain measurements in a small scale HF overtone laser

    Energy Technology Data Exchange (ETDEWEB)

    Wisniewski, C.F.; Hewett, K.B.; Manke, G.C. II; Hager, G.D. [Air Force Research Laboratory, Directed Energy Directorate, 3550 Aberdeen Ave SE, Kirtland AFB, NM 87117-5776 (United States); Crowell, P.G. [Northrup Grumman Information Technology, Science and Technology Operating Unit, Advanced Technology Division, P.O. Box 9377, Albuquerque, NM 87119-9377 (United States); Truman, C.R. [Mechanical Engineering Department, University of New Mexico, Albuquerque, NM 87131 (United States)

    2003-07-01

    The overtone gain medium of a small-scale HF overtone laser was probed using a sub-Doppler tunable diode laser. Two-dimensional spatially resolved small signal gain and temperature maps were generated for several ro-vibrational transitions in the HF (v=2{yields}v=0) overtone band. Our results compare well with previous measurements of the overtone gain in a similar HF laser device. (orig.)

  12. Small-scale impacts as potential trigger for landslides on small Solar system bodies

    Science.gov (United States)

    Hofmann, Marc; Sierks, Holger; Blum, Jürgen

    2017-07-01

    We conducted a set of experiments to investigate whether millimetre-sized impactors impinging on a granular material at several m s-1 are able to trigger avalanches on small, atmosphereless planetary bodies. These experiments were carried out at the Zentrum für angewandte Raumfahrttechnologie und Mikrogravitation (ZARM) drop tower facility in Bremen, Germany to facilitate a reduced gravity environment. Additional data were gathered at Earth gravity levels in the laboratory. As sample materials we used a ground Howardites, Eucrites and Diogenites (HED) meteorite and the Johnson Space Center (JSC) Mars-1 Martian soil simulant. We found that this type of small-scale impact can trigger avalanches with a moderate probability, if the target material is tilted to an angle close to the angle of repose. We additionally simulated a small-scale impact using the discrete element method code esys-particle. These simulations show that energy transfer from impactor to the target material is most efficient at low- and moderate-impactor inclinations and the transferred energy is retained in particles close to the surface due to a rapid dissipation of energy in lower material layers driven by inelastic collisions. Through Monte Carlo simulations we estimate the time-scale on which small-scale impacts with the observed characteristics will trigger avalanches covering all steep slopes on the surface of a small planetary body to be of the order 105 yr.

  13. Small-scale power plant potential in Finland

    International Nuclear Information System (INIS)

    Helynen, S.

    1993-01-01

    The presentation discusses the small-scale power plant potential in Finland. The study of the potential is limited to W-scale power plants producing both electric power and heat using solid fuels. The basic power plant dimensioning and electric power load determination is based on traditional boiler and gas turbine technology. The possible sites for power plants are communities using district heating, and industrialized sites needing process steam or heat. In 1990 70 % (17 TWh) of district heat was produced by gas turbines. Ten communities have an own back-pressure power plant, and 40 communities buy heat from industrial plants, owing back-pressure power generation. Additionally about 40 communes buy district heat from companies, owned by power companies and industry. Estimates of small-scale power plant potential has been made plant wise on the basis of district heat loads and industrial heat needs. The scale of the plants has been limited to scale 3 MWe or more. The choosing of the fuel depends on the local conditions. The cheapest indigenous fuels in many communes are industrial wood wastes, and both milled and sod peat. The potential of steam technology based small-scale power plants has been estimated to be about 50 plants in 1992/1993, the total power of which is 220-260 MW. The largest estimate is base situation, in which there would be energy cooperation between the communes and industry. The fuel used by the power plants would be about 5.4-6.6 TWh/a corresponding to 270-330 million FIM/a. The total investment costs of the plants would be about 2.0 billion FIM. The plants would employ about 250 persons, and the fuel supply (wood or peat) about 100 persons

  14. Effects of thermal inflation on small scale density perturbations

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Sungwook E. [School of Physics, Korea Institute for Advanced Study, 85 Hoegiro, Seoul 130-722 (Korea, Republic of); Lee, Hyung-Joo; Lee, Young Jae; Stewart, Ewan D. [Department of Physics, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 305-338 (Korea, Republic of); Zoe, Heeseung, E-mail: swhong@kias.re.kr, E-mail: ohsk111@kaist.ac.kr, E-mail: noasac@kaist.ac.kr, E-mail: jcap@profstewart.org, E-mail: heezoe@dgist.ac.kr [School of Basic Science, Daegu Gyeongbuk Institute of Science and Technology (DGIST), 333 Techno jungang-daero, Daegu 711-873 (Korea, Republic of)

    2015-06-01

    In cosmological scenarios with thermal inflation, extra eras of moduli matter domination, thermal inflation and flaton matter domination exist between primordial inflation and the radiation domination of Big Bang nucleosynthesis. During these eras, cosmological perturbations on small scales can enter and re-exit the horizon, modifying the power spectrum on those scales. The largest modified scale, k{sub b}, touches the horizon size when the expansion changes from deflation to inflation at the transition from moduli domination to thermal inflation. We analytically calculate the evolution of perturbations from moduli domination through thermal inflation and evaluate the curvature perturbation on the constant radiation density hypersurface at the end of thermal inflation to determine the late time curvature perturbation. Our resulting transfer function suppresses the power spectrum by a factor 0∼ 5 at k >> k{sub b}, with k{sub b} corresponding to anywhere from megaparsec to subparsec scales depending on the parameters of thermal inflation. Thus, thermal inflation might be constrained or detected by small scale observations such as CMB distortions or 21cm hydrogen line observations.

  15. Development of small scale soft x-ray lasers

    International Nuclear Information System (INIS)

    Kim, D.; Suckewer, S.; Princeton Univ., NJ; Skinner, C.H.; Voorhees, D.

    1991-05-01

    At present rapid progress is being made in the application of soft x-ray lasers to fields such as microscopy and microlithography. A critical factor in the range of suitable applications is the scale and hence cost of the soft x-ray lasers. At Princeton, gain at 183 angstrom has been obtained with relatively low pump laser energies (as low as 6J) in a ''portable'' small-scale soft x-ray laser system. We will also discuss aspects of data interpretation and pitfalls to be avoided in measurements of gain in such systems. 14 refs., 7 figs

  16. RPC Production at General Tecnica: a mass scale production

    International Nuclear Information System (INIS)

    Della Volpe, D.; Morganti, S.

    2006-01-01

    The construction of LHC has deeply changed the RPC production. The enormous amount of detector needed and the strong requirements on gas volume quality had a deep impact on the production chain and on the QC and QA at the production site. This basically has brought the RPC from an almost hand-crafted detector to a medium scale mass product. The most critical aspects of the production chain have been modified and/or improved introducing new and more rigorous QC and QA procedures to guarantee the detector quality and improve the management of storage and the procurement on materials. Here it will be presented the work carried on in the last four year at the production site to improve and check the quality and the results achieved. Something like 10000 RPC were produced between 2002 and 2005. Also a preliminary and rough analysis on the efficiencies of the various phases in the chain production based on ATLAS production will be presented

  17. Bt maize for small scale farmers: A case study | Keetch | African ...

    African Journals Online (AJOL)

    In South Africa, genetically modified (GM) white maize was approved for commercial production in 1998. To educate and inform small-scale farmers and to give them the opportunity to evaluate GM white maize for themselves, six demonstration plots were planted at strategic locations. This communications presents the ...

  18. Management of small-scale fisheries in developing countries : The case of Elephant Marsh in Malawi

    NARCIS (Netherlands)

    Kosamu, I.B.M.

    2017-01-01

    Wetlands provide many ecosystem goods and services which include fish production. The sustainability of small-scale fisheries (SSF) has received considerable attention in recent years because fish is one of the major sources of animal protein to a considerable fraction of the global population which

  19. Cultivating sources of competitive advantage : Opportunities for small-scale African farmers in global value chains

    NARCIS (Netherlands)

    Olthaar, Matthias

    2015-01-01

    Small-scale farmers in developing countries often appropriate little of the value created in global value chains. The farmers typically receive only a fraction of what consumers pay for a certain product. In the current thesis we studied which resources farmers have access to that enable them to

  20. Adapted Technology for Small-scale Manufacture of Caerphilly-Type ...

    African Journals Online (AJOL)

    Adapted Technology for Small-scale Manufacture of Caerphilly-Type Cheese from Cow's Milk in the Western Highlands Region of Cameroon. ... The production of the cheese should be encouraged at the household level. The Journal of Food Technology in Africa Volume 5 Number 4 (October - December 2000), pp. 120- ...

  1. Leadership solves collective action problems in small-scale societies

    Science.gov (United States)

    Glowacki, Luke; von Rueden, Chris

    2015-01-01

    Observation of leadership in small-scale societies offers unique insights into the evolution of human collective action and the origins of sociopolitical complexity. Using behavioural data from the Tsimane forager-horticulturalists of Bolivia and Nyangatom nomadic pastoralists of Ethiopia, we evaluate the traits of leaders and the contexts in which leadership becomes more institutional. We find that leaders tend to have more capital, in the form of age-related knowledge, body size or social connections. These attributes can reduce the costs leaders incur and increase the efficacy of leadership. Leadership becomes more institutional in domains of collective action, such as resolution of intragroup conflict, where collective action failure threatens group integrity. Together these data support the hypothesis that leadership is an important means by which collective action problems are overcome in small-scale societies. PMID:26503683

  2. Scaling effects concerning the analysis of small break experiments

    International Nuclear Information System (INIS)

    Austregesilo Filho, H.

    1985-01-01

    Some scaling effects related to the experimental facilities as well as to the analytical models used for the design and safety analysis of nuclear power plants are discussed or the basis of phenomena expected to occur during small-break loss - of - coolant accidents. The results of isolated small-break experiments should not be directly extrapolated to the safety analysis of commercial reactors, due to the scaling distortions inherent to the test facilities. With respect to the analytical models used to simulate thermohydraulic processes in experimental facilities, their eventual dependence relative to the system dimension should be examined in order to assess their applicability to the safety analysis of commercial power plants. (Author) [pt

  3. Sustainability Metrics of a Small Scale Turbojet Engine

    Science.gov (United States)

    Ekici, Selcuk; Sohret, Yasin; Coban, Kahraman; Altuntas, Onder; Karakoc, T. Hikmet

    2018-05-01

    Over the last decade, sustainable energy consumption has attracted the attention of scientists and researchers. The current paper presents sustainability indicators of a small scale turbojet engine, operated on micro-aerial vehicles, for discussion of the sustainable development of the aviation industry from a different perspective. Experimental data was obtained from an engine at full power load and utilized to conduct an exergy-based sustainability analysis. Exergy efficiency, waste exergy ratio, recoverable exergy ratio, environmental effect factor, exergy destruction factor and exergetic sustainability index are evaluated as exergetic sustainability indicators of the turbojet engine under investigation in the current study. The exergy efficiency of the small scale turbojet engine is calculated as 27.25 % whereas the waste exergy ratio, the exergy destruction factor and the sustainability index of the engine are found to be 0.9756, 0.5466 and 0.2793, respectively.

  4. Leadership solves collective action problems in small-scale societies.

    Science.gov (United States)

    Glowacki, Luke; von Rueden, Chris

    2015-12-05

    Observation of leadership in small-scale societies offers unique insights into the evolution of human collective action and the origins of sociopolitical complexity. Using behavioural data from the Tsimane forager-horticulturalists of Bolivia and Nyangatom nomadic pastoralists of Ethiopia, we evaluate the traits of leaders and the contexts in which leadership becomes more institutional. We find that leaders tend to have more capital, in the form of age-related knowledge, body size or social connections. These attributes can reduce the costs leaders incur and increase the efficacy of leadership. Leadership becomes more institutional in domains of collective action, such as resolution of intragroup conflict, where collective action failure threatens group integrity. Together these data support the hypothesis that leadership is an important means by which collective action problems are overcome in small-scale societies. © 2015 The Author(s).

  5. Small-Scale Combined Heat and Power Plants Using Biofuels

    Energy Technology Data Exchange (ETDEWEB)

    Salomon-Popa, Marianne [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Energy Technology

    2002-11-01

    In this time period where energy supply and climate change are of special concern, biomass-based fuels have attracted much interest due to their plentiful supply and favorable environmental characteristics (if properly managed). The effective capture and continued sustainability of this renewable resource requires a new generation of biomass power plants with high fuel energy conversion. At the same time, deregulation of the electricity market offers new opportunities for small-scale power plants in a decentralized scheme. These two important factors have opened up possibilities for small-scale combined heat and power (CHP) plants based on biofuels. The objective of this pre-study is to assess the possibilities and technical limitations for increased efficiency and energy utilization of biofuels in small size plants (approximately 10 MWe or lower). Various energy conversion technologies are considered and proven concepts for large-scale fossil fuel plants are an especially important area. An analysis has been made to identify the problems, technical limitations and different possibilities as recognized in the literature. Beyond published results, a qualitative survey was conducted to gain first-hand, current knowledge from experts in the field. At best, the survey results together with the results of personal interviews and a workshop on the role of small-scale plants in distributed generation will serve a guideline for future project directions and ideas. Conventional and novel technologies are included in the survey such as Stirling engines, combustion engines, gas turbines, steam turbines, steam motors, fuel cells and other novel technologies/cycles for biofuels. State-of-the-art heat and power plants will be identified to clarify of the advantages and disadvantages as well as possible obstacles for their implementation.

  6. Financing small-scale infrastructure investments in developing countries

    OpenAIRE

    Daniel L. Bond; Daniel Platz; Magnus Magnusson

    2012-01-01

    In most developing countries a shortage of long-term, local-currency financing for small-scale infrastructure projects impedes local economic development. Inadequate fiscal transfers, little own source revenue and low creditworthiness make it difficult for local governments to fully fund projects on their own. This paper proposes the use of project finance as a means to attract financing from domestic banks and institutional investors. Donors can play a catalytic role by providing technical a...

  7. Managing Small-Scale Fisheries : Alternative Directions and Methods

    International Development Research Centre (IDRC) Digital Library (Canada)

    Managing Small-scale Fisheries va plus loin que le champ d'application de la gestion classique des pêches pour aborder d'autres concepts, outils, méthodes et ... Les gestionnaires des pêches, tant du secteur public que du secteur privé, les chargés de cours et les étudiants en gestion des pêches, les organisations et les ...

  8. Integrated bioenergy conversion concepts for small scale gasification power systems

    Science.gov (United States)

    Aldas, Rizaldo Elauria

    Thermal and biological gasification are promising technologies for addressing the emerging concerns in biomass-based renewable energy, environmental protection and waste management. However, technical barriers such as feedstock quality limitations, tars, and high NOx emissions from biogas fueled engines impact their full utilization and make them suffer at the small scale from the need to purify the raw gas for most downstream processes, including power generation other than direct boiler use. The two separate gasification technologies may be integrated to better address the issues of power generation and waste management and to complement some of each technologies' limitations. This research project investigated the technical feasibility of an integrated thermal and biological gasification concept for parameters critical to appropriately matching an anaerobic digester with a biomass gasifier. Specific studies investigated the thermal gasification characteristics of selected feedstocks in four fixed-bed gasification experiments: (1) updraft gasification of rice hull, (2) indirect-heated gasification of rice hull, (3) updraft gasification of Athel wood, and (4) downdraft gasification of Athel and Eucalyptus woods. The effects of tars and other components of producer gas on anaerobic digestion at mesophilic temperature of 36°C and the biodegradation potentials and soil carbon mineralization of gasification tars during short-term aerobic incubation at 27.5°C were also examined. Experiments brought out the ranges in performance and quality and quantity of gasification products under different operating conditions and showed that within the conditions considered in the study, these gasification products did not adversely impact the overall digester performance. Short-term aerobic incubation demonstrated variable impacts on carbon mineralization depending on tar and soil conditions. Although tars exhibited low biodegradation indices, degradation may be improved if the

  9. Empirical spatial econometric modelling of small scale neighbourhood

    Science.gov (United States)

    Gerkman, Linda

    2012-07-01

    The aim of the paper is to model small scale neighbourhood in a house price model by implementing the newest methodology in spatial econometrics. A common problem when modelling house prices is that in practice it is seldom possible to obtain all the desired variables. Especially variables capturing the small scale neighbourhood conditions are hard to find. If there are important explanatory variables missing from the model, the omitted variables are spatially autocorrelated and they are correlated with the explanatory variables included in the model, it can be shown that a spatial Durbin model is motivated. In the empirical application on new house price data from Helsinki in Finland, we find the motivation for a spatial Durbin model, we estimate the model and interpret the estimates for the summary measures of impacts. By the analysis we show that the model structure makes it possible to model and find small scale neighbourhood effects, when we know that they exist, but we are lacking proper variables to measure them.

  10. Examples of backreaction of small-scale inhomogeneities in cosmology

    Science.gov (United States)

    Green, Stephen R.; Wald, Robert M.

    2013-06-01

    In previous work, we introduced a new framework to treat large-scale backreaction effects due to small-scale inhomogeneities in general relativity. We considered one-parameter families of spacetimes for which such backreaction effects can occur, and we proved that, provided the weak energy condition on matter is satisfied, the leading effect of small-scale inhomogeneities on large-scale dynamics is to produce a traceless effective stress-energy tensor that itself satisfies the weak energy condition. In this work, we illustrate the nature of our framework by providing two explicit examples of one-parameter families with backreaction. The first, based on previous work of Berger, is a family of polarized vacuum Gowdy spacetimes on a torus, which satisfies all of the assumptions of our framework. As the parameter approaches its limiting value, the metric uniformly approaches a smooth background metric, but spacetime derivatives of the deviation of the metric from the background metric do not converge uniformly to zero. The limiting metric has nontrivial backreaction from the small-scale inhomogeneities, with an effective stress energy that is traceless and satisfies the weak energy condition, in accord with our theorems. Our second one-parameter family consists of metrics which have a uniform Friedmann-Lemaître-Robertson-Walker limit. This family satisfies all of our assumptions with the exception of the weak energy condition for matter. In this case, the limiting metric has an effective stress-energy tensor which is not traceless. We emphasize the importance of imposing energy conditions on matter in studies of backreaction.

  11. The Multifractal Structure of Small-Scale Artificial Ionospheric Turbulence

    Directory of Open Access Journals (Sweden)

    Vybornov F. I.

    2013-03-01

    Full Text Available We present the results of investigation of a multifractal structure of the artificial ionospheric turbulence when the midlatitude ionosphere is affected by high-power radio waves. The experimental studies were performed on the basis of the SURA heating facility with the help of radio sounding of the disturbed region of ionospheric plasma by signals from the Earth’s orbital satellities. In the case of vertical radio sounding of the disturbed ionosphere region, the measured multipower and generalized multifractal spectra of turbulence coincide well with similar multifractal characteristics of the ionosperic turbulence under the natural conditions. In the case of oblique sounding of the disturbance region at small angles between the line of sight to the satellite and the direction of the Earth’s magnetic field, a nonuniform structure of the small-scale turbulence with a relatively narrow multipower spectrum and small variations in the generalized multifractal spectrum of the electron density was detected.

  12. Small is beautiful: Marine small-scale fisheries catches from the South-West Maluku Regency

    Science.gov (United States)

    Hutubessy, BG; Mosse, JW; Hayward, P.

    2017-10-01

    The fisheries data supplied by fisheries agency have served as the primary tool for regional fisheries statistics. However, it is recognized these data are incomplete and often underestimate actual catches, particularly for small-scale fisheries. There is no widely accepted definition of small-scale fisheries or global data on number of small-scale fishers and their catches. This study reconstructed total marine catches from 1980 to 2015 for South-west Maluku (MBD) regency, by applying an established catch construction approach utilizing all available quantitative and qualitative data, combined with assumption-based estimations and interpolations. As newly established regency since 2009, there is lack of fisheries data available which is needed for fisheries management. Fishers’ knowledge is important information taken from to construct long-term fisheries data. Estimated total fish withdrawal from MBD waters was 86,849.66 tonnes during 1980 - 2015, dominated by pelagic fishes. Consistency of estimated total removal and total landings at MBD regency play important role in small-scale fisheries management and this method of visualizing the history of fishery from poor-data condition might be an optimistic effort.

  13. Small-scale variability in tropical tropopause layer humidity

    Science.gov (United States)

    Jensen, E. J.; Ueyama, R.; Pfister, L.; Karcher, B.; Podglajen, A.; Diskin, G. S.; DiGangi, J. P.; Thornberry, T. D.; Rollins, A. W.; Bui, T. V.; Woods, S.; Lawson, P.

    2016-12-01

    Recent advances in statistical parameterizations of cirrus cloud processes for use in global models are highlighting the need for information about small-scale fluctuations in upper tropospheric humidity and the physical processes that control the humidity variability. To address these issues, we have analyzed high-resolution airborne water vapor measurements obtained in the Airborne Tropical TRopopause EXperiment over the tropical Pacific between 14 and 20 km. Using accurate and precise 1-Hz water vapor measurements along approximately-level aircraft flight legs, we calculate structure functions spanning horizontal scales ranging from about 0.2 to 50 km, and we compare the water vapor variability in the lower (about 14 km) and upper (16-19 km) Tropical Tropopause Layer (TTL). We also compare the magnitudes and scales of variability inside TTL cirrus versus in clear-sky regions. The measurements show that in the upper TTL, water vapor concentration variance is stronger inside cirrus than in clear-sky regions. Using simulations of TTL cirrus formation, we show that small variability in clear-sky humidity is amplified by the strong sensitivity of ice nucleation rate to supersaturation, which results in highly-structured clouds that subsequently drive variability in the water vapor field. In the lower TTL, humidity variability is correlated with recent detrainment from deep convection. The structure functions indicate approximately power-law scaling with spectral slopes ranging from about -5/3 to -2.

  14. Passive Plasma Contact Mechanisms for Small-Scale Spacecraft

    Science.gov (United States)

    McTernan, Jesse K.

    Small-scale spacecraft represent a paradigm shift in how entities such as academia, industry, engineering firms, and the scientific community operate in space. However, although the paradigm shift produces unique opportunities to build satellites in unique ways for novel missions, there are also significant challenges that must be addressed. This research addresses two of the challenges associated with small-scale spacecraft: 1) the miniaturization of spacecraft and associated instrumentation and 2) the need to transport charge across the spacecraft-environment boundary. As spacecraft decrease in size, constraints on the size, weight, and power of on-board instrumentation increase--potentially limiting the instrument's functionality or ability to integrate with the spacecraft. These constraints drive research into mechanisms or techniques that use little or no power and efficiently utilize existing resources. One limited resource on small-scale spacecraft is outer surface area, which is often covered with solar panels to meet tight power budgets. This same surface area could also be needed for passive neutralization of spacecraft charging. This research explores the use of a transparent, conductive layer on the solar cell coverglass that is electrically connected to spacecraft ground potential. This dual-purpose material facilitates the use of outer surfaces for both energy harvesting of solar photons as well as passive ion collection. Mission capabilities such as in-situ plasma measurements that were previously infeasible on small-scale platforms become feasible with the use of indium tin oxide-coated solar panel coverglass. We developed test facilities that simulate the space environment in low Earth orbit to test the dual-purpose material and the various application of this approach. Particularly, this research is in support of two upcoming missions: OSIRIS-3U, by Penn State's Student Space Programs Lab, and MiTEE, by the University of Michigan. The purpose of

  15. Small-scale semi-continuous reactor for the conversion of wood to fuel oil

    Energy Technology Data Exchange (ETDEWEB)

    Eager, R L; Pepper, J M; Mathews, J F

    1983-04-01

    The design and operation of a small-scale semi-continuous reactor to convert aspen wood meal into an oil product is described. Modifications that reduce erosion/corrosion are also presented. Short residence times and relatively low operating pressures have been achieved for the reaction of aspen with CO and H2O in the presence of Na2CO3. Conversions, char formation, and the effect of sodium carbonate concentration on oil product are reported.

  16. Small-Scale Spray Releases: Additional Aerosol Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Schonewill, Philip P.; Gauglitz, Phillip A.; Kimura, Marcia L.; Brown, G. N.; Mahoney, Lenna A.; Tran, Diana N.; Burns, Carolyn A.; Kurath, Dean E.

    2013-08-01

    One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. To expand the data set upon which the WTP accident and safety analyses were based, an aerosol spray leak testing program was conducted by Pacific Northwest National Laboratory (PNNL). PNNL’s test program addressed two key technical areas to improve the WTP methodology (Larson and Allen 2010). The first technical area was to quantify the role of slurry particles in small breaches where slurry particles may plug the hole and prevent high-pressure sprays. The results from an effort to address this first technical area can be found in Mahoney et al. (2012a). The second technical area was to determine aerosol droplet size distribution and total droplet volume from prototypic breaches and fluids, including sprays from larger breaches and sprays of slurries for which literature data are largely absent. To address the second technical area, the testing program collected aerosol generation data at two scales, commonly referred to as small-scale and large-scale. The small-scale testing and resultant data are described in Mahoney et al. (2012b) and the large-scale testing and resultant data are presented in Schonewill et al. (2012). In tests at both scales, simulants were used to mimic the

  17. Large Scale Community Detection Using a Small World Model

    Directory of Open Access Journals (Sweden)

    Ranjan Kumar Behera

    2017-11-01

    Full Text Available In a social network, small or large communities within the network play a major role in deciding the functionalities of the network. Despite of diverse definitions, communities in the network may be defined as the group of nodes that are more densely connected as compared to nodes outside the group. Revealing such hidden communities is one of the challenging research problems. A real world social network follows small world phenomena, which indicates that any two social entities can be reachable in a small number of steps. In this paper, nodes are mapped into communities based on the random walk in the network. However, uncovering communities in large-scale networks is a challenging task due to its unprecedented growth in the size of social networks. A good number of community detection algorithms based on random walk exist in literature. In addition, when large-scale social networks are being considered, these algorithms are observed to take considerably longer time. In this work, with an objective to improve the efficiency of algorithms, parallel programming framework like Map-Reduce has been considered for uncovering the hidden communities in social network. The proposed approach has been compared with some standard existing community detection algorithms for both synthetic and real-world datasets in order to examine its performance, and it is observed that the proposed algorithm is more efficient than the existing ones.

  18. Energy transfers in large-scale and small-scale dynamos

    Science.gov (United States)

    Samtaney, Ravi; Kumar, Rohit; Verma, Mahendra

    2015-11-01

    We present the energy transfers, mainly energy fluxes and shell-to-shell energy transfers in small-scale dynamo (SSD) and large-scale dynamo (LSD) using numerical simulations of MHD turbulence for Pm = 20 (SSD) and for Pm = 0.2 on 10243 grid. For SSD, we demonstrate that the magnetic energy growth is caused by nonlocal energy transfers from the large-scale or forcing-scale velocity field to small-scale magnetic field. The peak of these energy transfers move towards lower wavenumbers as dynamo evolves, which is the reason for the growth of the magnetic fields at the large scales. The energy transfers U2U (velocity to velocity) and B2B (magnetic to magnetic) are forward and local. For LSD, we show that the magnetic energy growth takes place via energy transfers from large-scale velocity field to large-scale magnetic field. We observe forward U2U and B2B energy flux, similar to SSD.

  19. Impact of small-scale geometric roughness on wetting behavior.

    Science.gov (United States)

    Kumar, Vaibhaw; Errington, Jeffrey R

    2013-09-24

    We examine the extent to which small-scale geometric substrate roughness influences the wetting behavior of fluids at solid surfaces. Molecular simulation is used to construct roughness wetting diagrams wherein the progression of the contact angle is traced from the Cassie to Wenzel to impregnation regime with increasing substrate strength for a collection of systems with rectangularly shaped grooves. We focus on the evolution of these diagrams as the length scale of the substrate features approaches the size of a fluid molecule. When considering a series of wetting diagrams for substrates with fixed shape and variable feature periodicity, we find that the diagrams progressively shift away from a common curve as the substrate features become smaller than approximately 10 fluid diameters. It is at this length scale that the macroscopic models of Cassie and Wenzel become unreliable. Deviations from the macroscopic models are attributed to the manner in which the effective substrate-fluid interaction strength evolves with periodicity and the important role that confinement effects play for substrates with small periodicities.

  20. Atmospheric dispersion modelling over complex terrain at small scale

    Science.gov (United States)

    Nosek, S.; Janour, Z.; Kukacka, L.; Jurcakova, K.; Kellnerova, R.; Gulikova, E.

    2014-03-01

    Previous study concerned of qualitative modelling neutrally stratified flow over open-cut coal mine and important surrounding topography at meso-scale (1:9000) revealed an important area for quantitative modelling of atmospheric dispersion at small-scale (1:3300). The selected area includes a necessary part of the coal mine topography with respect to its future expansion and surrounding populated areas. At this small-scale simultaneous measurement of velocity components and concentrations in specified points of vertical and horizontal planes were performed by two-dimensional Laser Doppler Anemometry (LDA) and Fast-Response Flame Ionization Detector (FFID), respectively. The impact of the complex terrain on passive pollutant dispersion with respect to the prevailing wind direction was observed and the prediction of the air quality at populated areas is discussed. The measured data will be used for comparison with another model taking into account the future coal mine transformation. Thus, the impact of coal mine transformation on pollutant dispersion can be observed.

  1. Variability of the raindrop size distribution at small spatial scales

    Science.gov (United States)

    Berne, A.; Jaffrain, J.

    2010-12-01

    Because of the interactions between atmospheric turbulence and cloud microphysics, the raindrop size distribution (DSD) is strongly variable in space and time. The spatial variability of the DSD at small spatial scales (below a few km) is not well documented and not well understood, mainly because of a lack of adequate measurements at the appropriate resolutions. A network of 16 disdrometers (Parsivels) has been designed and set up over EPFL campus in Lausanne, Switzerland. This network covers a typical operational weather radar pixel of 1x1 km2. The question of the significance of the variability of the DSD at such small scales is relevant for radar remote sensing of rainfall because the DSD is often assumed to be uniform within a radar sample volume and because the Z-R relationships used to convert the measured radar reflectivity Z into rain rate R are usually derived from point measurements. Thanks to the number of disdrometers, it was possible to quantify the spatial variability of the DSD at the radar pixel scale and to show that it can be significant. In this contribution, we show that the variability of the total drop concentration, of the median volume diameter and of the rain rate are significant, taking into account the sampling uncertainty associated with disdrometer measurements. The influence of this variability on the Z-R relationship can be non-negligible. Finally, the spatial structure of the DSD is quantified using a geostatistical tool, the variogram, and indicates high spatial correlation within a radar pixel.

  2. Scale up of proteoliposome derived Cochleate production.

    Science.gov (United States)

    Zayas, Caridad; Bracho, Gustavo; Lastre, Miriam; González, Domingo; Gil, Danay; Acevedo, Reinaldo; del Campo, Judith; Taboada, Carlos; Solís, Rosa L; Barberá, Ramón; Pérez, Oliver

    2006-04-12

    Cochleate are highly stable structures with promising immunological features. Cochleate structures are usually obtaining from commercial lipids. Proteoliposome derived Cochleate are derived from an outer membrane vesicles of Neisseria meningitidis B. Previously, we obtained Cochleates using dialysis procedures. In order to increase the production process, we used a crossflow system (CFS) that allows easy scale up to obtain large batches in an aseptic environment. The raw material and solutions used in the production process are already approved for human application. This work demonstrates that CFS is very efficient process to obtain Cochleate structures with a yield of more than 80% and the immunogenicity comparable to that obtained by dialysis membrane.

  3. Concepts for Large Scale Hydrogen Production

    OpenAIRE

    Jakobsen, Daniel; Åtland, Vegar

    2016-01-01

    The objective of this thesis is to perform a techno-economic analysis of large-scale, carbon-lean hydrogen production in Norway, in order to evaluate various production methods and estimate a breakeven price level. Norway possesses vast energy resources and the export of oil and gas is vital to the country s economy. The results of this thesis indicate that hydrogen represents a viable, carbon-lean opportunity to utilize these resources, which can prove key in the future of Norwegian energy e...

  4. Commercial Scale Production of Mushroom Liquid Seeds

    International Nuclear Information System (INIS)

    Rosnani Abdul Rashid; Hassan Hamdani Hassan Mutaat; Mohd Meswan Maskom; Khairuddin Abdul Rahim

    2015-01-01

    Mushroom liquid seed production technology was developed by Malaysian Nuclear Agency (Nuclear Malaysia) in the late 1990s. Initially, the liquid seeds were used mainly in the solid state fermentation process for converting oil palm empty fruit bunch fibres into ruminant feed. Considering widespread problems encountered by mushroom growers from use of solid seeds, especially in cases of contaminant agents infecting cultivated bags and inconsistencies in yield, we diverted our focus to utilising liquid seeds as alternative inocula for mushroom cultivation. These problems provide us opportunities to look into the issues and address the problems faced by mushroom growers. However, the technology of producing liquid seed at laboratory scale needs to be primed for commercial production. This paper discusses developmental aspects of mushroom liquid seed at commercial scale for the advancement of the country's mushroom industry. (author)

  5. Exploring the role of small-scale livestock keepers for national biosecurity-The pig case.

    Science.gov (United States)

    Correia-Gomes, Carla; Henry, Madeleine K; Auty, Harriet K; Gunn, George J

    2017-09-15

    Small-scale keepers are less likely to engage with production organisations and may therefore be less aware of legislation, rules and biosecurity practices which are implemented in the livestock sector. Their role in the transmission of endemic and exotic diseases is not well studied, but is believed to be important. The authors use small-scale pig keepers in Scotland as an example of how important small-scale livestock keepers might be for national biosecurity. In Scotland more than two thirds of pig producers report that they keep less than 10 pigs, meaning that biosecurity practices and pig health status on a substantial number of holdings are largely unknown; it is considered important to fill this knowledge gap. A questionnaire was designed and implemented in order to gather some of this information. The questionnaire comprised a total of 37 questions divided into seven sections (location of the enterprise, interest in pigs, details about the pig enterprise, marketing of pigs, transport of pigs, pig husbandry, and pig health/biosecurity). Over 610 questionnaires were sent through the post and the questionnaire was also available online. The questionnaire was implemented from June to October 2013 and 135 questionnaires were returned by target respondents. The responses for each question are discussed in detail in this paper. Overall, our results suggest that the level of disease identified by small-scale pig keepers is low but the majority of the small-scale pig keepers are mixed farms, with associated increased risk for disease transmission between species. Almost all respondents implemented at least one biosecurity measure, although the measures taken were not comprehensive in the majority of cases. Overall as interaction between small-scale keepers and commercial producers exists in Scotland the former can pose a risk for commercial production. This investigation fills gaps in knowledge which will allow industry stakeholders and policy makers to adapt their

  6. Unit Price Scaling Trends for Chemical Products

    Energy Technology Data Exchange (ETDEWEB)

    Qi, Wei [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sathre, Roger [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Morrow, III, William R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Shehabi, Arman [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-08-01

    To facilitate early-stage life-cycle techno-economic modeling of emerging technologies, here we identify scaling relations between unit price and sales quantity for a variety of chemical products of three categories - metal salts, organic compounds, and solvents. We collect price quotations for lab-scale and bulk purchases of chemicals from both U.S. and Chinese suppliers. We apply a log-log linear regression model to estimate the price discount effect. Using the median discount factor of each category, one can infer bulk prices of products for which only lab-scale prices are available. We conduct out-of-sample tests showing that most of the price proxies deviate from their actual reference prices by a factor less than ten. We also apply the bootstrap method to determine if a sample median discount factor should be accepted for price approximation. We find that appropriate discount factors for metal salts and for solvents are both -0.56, while that for organic compounds is -0.67 and is less representative due to greater extent of product heterogeneity within this category.

  7. Risk management strategies on small-scale commercial farms in three zobatat of Eritrea

    Directory of Open Access Journals (Sweden)

    MA Mohammed

    2014-05-01

    Full Text Available In this study the perceptions of small-scale commercial farmers in Eritrea of the importance of various risk responses are ascertained and analysed to gain insight into their risk-management strategies.  Data were elicited through a survey of 186 small-scale commercial farmers conducted in three zobatat (regions of Eritrea. Factor Analysis is used to investigate heterogeneity in sample farmers’ responses.  Results indicate that relatively more important risk responses include the use of internal and external sources of information, on-farm and off-farm diversification, choice of production system and product marketing arrangements. Farmers’ perceptions of risk responses vary according to farm type, geographical location, farm and farmer characteristics, as well as the existence of enterprise specific risk responses (e.g. livestock insurance and differences in the marketing regulations of various agricultural products.

  8. The situation of rural women in Spain: the case of small-scale artisan food producers

    Directory of Open Access Journals (Sweden)

    Veronica Escurriol Martinez

    2014-11-01

    Full Text Available Rural women's discrimination and the lack of effective implementation of the legislation on gender equality is a phenomenon found around the world. Women have been traditionally the responsible of family care and feeding, thus they have developed productive tasks that allow combining productive and reproductive activities in the farm. Food processing is one of these activities and it allows women to have a paid work or to complement agrarian rents in a context where most of agricultural works are vetoed to them. Nevertheless, women are usually linked to small-scale agricultural projects which prioritize quality and local food production, and the expansion of industrial food systems has worsened the situation of artisan women. In the present research we aimed, through the use of qualitative methodologies, at conducting a diagnosis of the situation of women leading small-scale food transformation projects in Spain while eliciting their main difficulties, needs and claims.

  9. Design of a Small Scale Roll to Roll Device

    OpenAIRE

    Pereira, Amon A; White, Edward; Kramer, Rebecca Krone

    2014-01-01

    In the soft robotics field, hyperelastic polymer films are used in conjunction with eutectic gallium indium to create flexible strain gages. However, rapid large scale manufacturing methods of such sensors have yet to be developed. Developing new manufacturing methods will allow for researchers to build and test new soft sensor concepts faster but also pave the way for future mass-production of these sensors for consumer or industrial consumption. One of those methods would be a Roll to...

  10. Small scale wind energy harvesting with maximum power tracking

    Directory of Open Access Journals (Sweden)

    Joaquim Azevedo

    2015-07-01

    Full Text Available It is well-known that energy harvesting from wind can be used to power remote monitoring systems. There are several studies that use wind energy in small-scale systems, mainly with wind turbine vertical axis. However, there are very few studies with actual implementations of small wind turbines. This paper compares the performance of horizontal and vertical axis wind turbines for energy harvesting on wireless sensor network applications. The problem with the use of wind energy is that most of the time the wind speed is very low, especially at urban areas. Therefore, this work includes a study on the wind speed distribution in an urban environment and proposes a controller to maximize the energy transfer to the storage systems. The generated power is evaluated by simulation and experimentally for different load and wind conditions. The results demonstrate the increase in efficiency of wind generators that use maximum power transfer tracking, even at low wind speeds.

  11. Pervasive Rise of Small-scale Deforestation in Amazonia.

    Science.gov (United States)

    Kalamandeen, Michelle; Gloor, Emanuel; Mitchard, Edward; Quincey, Duncan; Ziv, Guy; Spracklen, Dominick; Spracklen, Benedict; Adami, Marcos; Aragão, Luiz E O C; Galbraith, David

    2018-01-25

    Understanding forest loss patterns in Amazonia, the Earth's largest rainforest region, is critical for effective forest conservation and management. Following the most detailed analysis to date, spanning the entire Amazon and extending over a 14-year period (2001-2014), we reveal significant shifts in deforestation dynamics of Amazonian forests. Firstly, hotspots of Amazonian forest loss are moving away from the southern Brazilian Amazon to Peru and Bolivia. Secondly, while the number of new large forest clearings (>50 ha) has declined significantly over time (46%), the number of new small clearings (<1 ha) increased by 34% between 2001-2007 and 2008-2014. Thirdly, we find that small-scale low-density forest loss expanded markedly in geographical extent during 2008-2014. This shift presents an important and alarming new challenge for forest conservation, despite reductions in overall deforestation rates.

  12. Performance analysis of small-scale experimental facility of TWDEC

    International Nuclear Information System (INIS)

    Kawana, Ryoh; Ishikawa, Motoo; Takeno, Hiromasa; Yamamoto, Takayoshi; Yasaka, Yasuyoshi

    2008-01-01

    The objective of the present paper is to analyze small-scale experimental facilities of TWDEC (Travelling Wave type Direct Energy Converter) and to propose a modification in regard to a measuring device of the facilities by means of numerical simulation with the axisymmetrical two-dimensional approximation (a PIC method). The numerical simulation has given the following results: (1) tendency of the numerical results agree with the experimental results on the measured deceleration efficiency, (2) the deceleration efficiency measured in the experiment will increase if the radius of Faraday cup installed in the experiment increases and (3) the wave of condensation and rarefaction of measured electric charge density, which is averaged in the r-direction below the radius of Faraday cup, is not formed enough with a small radius of Faraday cup because of the r component of electric field which is induced by the electrode geometry

  13. Small Scale Turbopump Manufacturing Technology and Material Processes

    Science.gov (United States)

    Alvarez, Erika; Morgan, Kristin; Wells, Doug; Zimmerman, Frank

    2011-01-01

    As part of an internal research and development project, NASA Marshall Space Flight Center (MSFC) has been developing a high specific impulse 9,000-lbf LOX/LH2 pump-fed engine testbed with the capability to throttle 10:1. A Fuel Turbopump (FTP) with the ability to operate across a speed range of 30,000-rpm to 100,000-rpm was developed and analyzed. This small size and flight-like Fuel Turbopump has completed the design and analysis phase and is currently in the manufacturing phase. This paper highlights the manufacturing and processes efforts to fabricate an approximately 20-lb turbopump with small flow passages, intricately bladed components and approximately 3-in diameter impellers. As a result of the small scale and tight tolerances of the hardware on this turbopump, several unique manufacturing and material challenges were encountered. Some of the technologies highlighted in this paper include the use of powder metallurgy technology to manufacture small impellers, electron beam welding of a turbine blisk shroud, and casting challenges. The use of risk reduction efforts such as non-destructive testing (NDT) and evaluation (NDE), fractography, material testing, and component spin testing are also discussed in this paper.

  14. Cost and primary energy efficiency of small-scale district heating systems

    International Nuclear Information System (INIS)

    Truong, Nguyen Le; Gustavsson, Leif

    2014-01-01

    Highlights: • We analyzed minimum-cost options for small-scale DHSs under different contexts. • District heat production cost increases with reduced DHS scales. • Fewer technical options are suitable for small-scale DHSs. • Systems with combined technologies are less sensitive to changes in fuel prices. - Abstract: Efficient district heat production systems (DHSs) can contribute to achieving environmental targets and energy security for countries that have demands for space and water heating. The optimal options for a DHS vary with the environmental and social-political contexts and the scale of district heat production, which further depends on the size of the community served and the local climatic conditions. In this study, we design a small-scale, minimum-cost DHS that produces approximately 100 GWh heat per year and estimate the yearly production cost and primary energy use of this system. We consider conventional technologies, such as heat-only boilers, electric heat pumps and combined heat and power (CHP) units, as well as emerging technologies, such as biomass-based organic Rankine cycle (BORC) and solar water heating (SWH). We explore how different environmental and social-political situations influence the design of a minimum-cost DHS and consider both proven and potential technologies for small-scale applications. Our calculations are based on the real heat load duration curve for a town in southern Sweden. We find that the district heat production cost increases and that the potential for cogeneration decreases with smaller district heat production systems. Although the selection of technologies for a minimum-cost DHS depends on environmental and social-political contexts, fewer technical options are suitable for small-scale systems. Emerging technologies such as CHP-BORC and SWH improve the efficiency of primary energy use for heat production, but these technologies are more costly than conventional heat-only boilers. However, systems with

  15. Concepts for Small-Scale Testing of Used Nuclear Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Marschman, Steven Craig [Idaho National Lab. (INL), Idaho Falls, ID (United States); Winston, Philip Lon [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-09-01

    This report documents a concept for a small-scale test involving between one and three Boiling Water Rector (BWR) high burnup (HBU) fuel assemblies. This test would be similar to the DOE funded High Burn-Up (HBU) Confirmatory Data Project to confirm the behavior of used high burn-up fuel under prototypic conditions, only on a smaller scale. The test concept proposed would collect data from fuel stored under prototypic dry storage conditions to mimic, as closely as possible, the conditions HBU UNF experiences during all stages of dry storage: loading, cask drying, inert gas backfilling, and transfer to an Independent Spent Fuel Storage Installation (ISFSI) for multi-year storage.

  16. Aerodynamics of small-scale vertical-axis wind turbines

    Science.gov (United States)

    Paraschivoiu, I.; Desy, P.

    1985-12-01

    The purpose of this work is to study the influence of various rotor parameters on the aerodynamic performance of a small-scale Darrieus wind turbine. To do this, a straight-bladed Darrieus rotor is calculated by using the double-multiple-streamtube model including the streamtube expansion effects through the rotor (CARDAAX computer code) and the dynamicstall effects. The straight-bladed Darrieus turbine is as expected more efficient with respect the curved-bladed rotor but for a given solidity is operates at higher wind speeds.

  17. Interactive economic analysis of small-scale heating plant

    Energy Technology Data Exchange (ETDEWEB)

    Landen, R.A.; Sanders, D.L.; Douglas, B.H.

    1998-11-01

    This report contains the work that has been undertaken by LRZ Limited in pursuance of this agreement. The potential for small-scale biomass heating systems is identified, and surrounding issues relating to acceptance are discussed. Such systems are described, and the origins of capital and running costs examined. A full review of the calculation methods for boiler plant size and fuel consumption is made, and subsequently expounded in four varying case studies. The results of this work are discussed, and the final development of the computer models is reviewed, incorporating further refinements to the method. Finally, data not contained in the text is incorporated in comprehensive appendices. (author)

  18. Small-scale generator opportunities in the competitive supply market

    International Nuclear Information System (INIS)

    Scrivener, G.

    1998-01-01

    The last franchises for electricity supply held by Public Electricity Suppliers are due to expire early in 1998. As a consequence from then on, after a phased start-up, all electricity consumers will be free to choose their supplier, completing the process of introducing competition into the electricity market which started in 1990 with the privatisation of the Industry. Then the framework by which the industry operates will become very different. This paper will review the changes to the operation of the market and assess the opportunities for small scale embedded generators post 1998. (Author)

  19. Thermodynamic comparison of three small-scale gas liquefaction systems

    DEFF Research Database (Denmark)

    Nguyen, Tuong-Van; Rothuizen, Erasmus Damgaard; Markussen, Wiebke Brix

    2017-01-01

    . The present work investigates three configurations suitable for small-scale applications because of their simplicity and compactness: the single-mixed refrigerant, single and dual reverse Brayton cycles. The impact of different feed compositions and refrigerant properties is analysed. A detailed assessment...... to be more efficient (1000-2000 kJ/kgLNG) than expander-based ones (2500-5000 kJ/kgLNG) over larger ranges of operating conditions, at the expense of a greater system complexity and higher thermal conductance (250-500kW/K against 80-160 kW/K). The results show that the use of different thermodynamic models...

  20. Small-scale generator opportunities in the competitive supply market

    Energy Technology Data Exchange (ETDEWEB)

    Scrivener, G. [Energy Technology Support Unit (ETSU), Harwell (United Kingdom)

    1998-07-01

    The last franchises for electricity supply held by Public Electricity Suppliers are due to expire early in 1998. As a consequence from then on, after a phased start-up, all electricity consumers will be free to choose their supplier, completing the process of introducing competition into the electricity market which started in 1990 with the privatisation of the Industry. Then the framework by which the industry operates will become very different. This paper will review the changes to the operation of the market and assess the opportunities for small scale embedded generators post 1998. (Author)

  1. Model Predictive Control for a Small Scale Unmanned Helicopter

    Directory of Open Access Journals (Sweden)

    Jianfu Du

    2008-11-01

    Full Text Available Kinematical and dynamical equations of a small scale unmanned helicoper are presented in the paper. Based on these equations a model predictive control (MPC method is proposed for controlling the helicopter. This novel method allows the direct accounting for the existing time delays which are used to model the dynamics of actuators and aerodynamics of the main rotor. Also the limits of the actuators are taken into the considerations during the controller design. The proposed control algorithm was verified in real flight experiments where good perfomance was shown in postion control mode.

  2. Small Scales Structure of MHD Turbulence, Tubes or Ribbons?

    Science.gov (United States)

    Verdini, A.; Grappin, R.; Alexandrova, O.; Lion, S.

    2017-12-01

    Observations in the solar wind indicate that turbulent eddies change their anisotropy with scales [1]. At large scales eddies are elongated in direction perpendicular to the mean-field axis. This is the result of solar wind expansion that affects both the anisotropy and single-spacecraft measurments [2,3]. At small scales one recovers the anisotropy expected in strong MHD turbulence and constrained by the so-called critical balance: eddies are elongated along the mean-field axis. However, the actual eddy shape is intermediate between tubes and ribbons, preventing us to discriminate between two concurrent theories that predict 2D axysimmetric anisotropy [4] or full 3D anisotropy [5]. We analyse 10 years of WIND data and apply a numerically-derived criterion to select intervals in which solar wind expansion is expected to be negligible. By computing the anisotropy of structure functions with respect to the local mean field we obtain for the first time scaling relations that are in agreement with full 3D anisotropy, i.e. ribbons-like structures. However, we cannot obtain the expected scaling relations for the alignment angle which, according to the theory, is physically responsible for the departure from axisymmetry. In addition, a further change of anisotropy occurs well above the proton scales. We discuss the implication of our findings and how numerical simulations can help interpreting the observed spectral anisotropy. [1] Chen et al., ApJ, 768:120, 2012 [2] Verdini & Grappin, ApJL, 808:L34, 2015 [3] Vech & Chen, ApJL, 832:L16, 2016 [4] Goldreich & Shridar, ApJ, 438:763, 1995 [5] Boldyrev, ApJL, 626:L37, 2005

  3. Dark matter self-interactions and small scale structure

    Science.gov (United States)

    Tulin, Sean; Yu, Hai-Bo

    2018-02-01

    We review theories of dark matter (DM) beyond the collisionless paradigm, known as self-interacting dark matter (SIDM), and their observable implications for astrophysical structure in the Universe. Self-interactions are motivated, in part, due to the potential to explain long-standing (and more recent) small scale structure observations that are in tension with collisionless cold DM (CDM) predictions. Simple particle physics models for SIDM can provide a universal explanation for these observations across a wide range of mass scales spanning dwarf galaxies, low and high surface brightness spiral galaxies, and clusters of galaxies. At the same time, SIDM leaves intact the success of ΛCDM cosmology on large scales. This report covers the following topics: (1) small scale structure issues, including the core-cusp problem, the diversity problem for rotation curves, the missing satellites problem, and the too-big-to-fail problem, as well as recent progress in hydrodynamical simulations of galaxy formation; (2) N-body simulations for SIDM, including implications for density profiles, halo shapes, substructure, and the interplay between baryons and self-interactions; (3) semi-analytic Jeans-based methods that provide a complementary approach for connecting particle models with observations; (4) merging systems, such as cluster mergers (e.g., the Bullet Cluster) and minor infalls, along with recent simulation results for mergers; (5) particle physics models, including light mediator models and composite DM models; and (6) complementary probes for SIDM, including indirect and direct detection experiments, particle collider searches, and cosmological observations. We provide a summary and critical look for all current constraints on DM self-interactions and an outline for future directions.

  4. Development of small scale cluster computer for numerical analysis

    Science.gov (United States)

    Zulkifli, N. H. N.; Sapit, A.; Mohammed, A. N.

    2017-09-01

    In this study, two units of personal computer were successfully networked together to form a small scale cluster. Each of the processor involved are multicore processor which has four cores in it, thus made this cluster to have eight processors. Here, the cluster incorporate Ubuntu 14.04 LINUX environment with MPI implementation (MPICH2). Two main tests were conducted in order to test the cluster, which is communication test and performance test. The communication test was done to make sure that the computers are able to pass the required information without any problem and were done by using simple MPI Hello Program where the program written in C language. Additional, performance test was also done to prove that this cluster calculation performance is much better than single CPU computer. In this performance test, four tests were done by running the same code by using single node, 2 processors, 4 processors, and 8 processors. The result shows that with additional processors, the time required to solve the problem decrease. Time required for the calculation shorten to half when we double the processors. To conclude, we successfully develop a small scale cluster computer using common hardware which capable of higher computing power when compare to single CPU processor, and this can be beneficial for research that require high computing power especially numerical analysis such as finite element analysis, computational fluid dynamics, and computational physics analysis.

  5. Small-scale engagement model with arrivals: analytical solutions

    International Nuclear Information System (INIS)

    Engi, D.

    1977-04-01

    This report presents an analytical model of small-scale battles. The specific impetus for this effort was provided by a need to characterize hypothetical battles between guards at a nuclear facility and their potential adversaries. The solution procedure can be used to find measures of a number of critical parameters; for example, the win probabilities and the expected duration of the battle. Numerical solutions are obtainable if the total number of individual combatants on the opposing sides is less than 10. For smaller force size battles, with one or two combatants on each side, symbolic solutions can be found. The symbolic solutions express the output parameters abstractly in terms of symbolic representations of the input parameters while the numerical solutions are expressed as numerical values. The input parameters are derived from the probability distributions of the attrition and arrival processes. The solution procedure reduces to solving sets of linear equations that have been constructed from the input parameters. The approach presented in this report does not address the problems associated with measuring the inputs. Rather, this report attempts to establish a relatively simple structure within which small-scale battles can be studied

  6. Small-Scale Smart Grid Construction and Analysis

    Science.gov (United States)

    Surface, Nicholas James

    The smart grid (SG) is a commonly used catch-phrase in the energy industry yet there is no universally accepted definition. The objectives and most useful concepts have been investigated extensively in economic, environmental and engineering research by applying statistical knowledge and established theories to develop simulations without constructing physical models. In this study, a small-scale version (SSSG) is constructed to physically represent these ideas so they can be evaluated. Results of construction show data acquisition three times more expensive than the grid itself although mainly due to the incapability to downsize 70% of data acquisition costs to small-scale. Experimentation on the fully assembled grid exposes the limitations of low cost modified sine wave power, significant enough to recommend pure sine wave investment in future SSSG iterations. Findings can be projected to full-size SG at a ratio of 1:10, based on the appliance representing average US household peak daily load. However this exposes disproportionalities in the SSSG compared with previous SG investigations and recommended changes for future iterations are established to remedy this issue. Also discussed are other ideas investigated in the literature and their suitability for SSSG incorporation. It is highly recommended to develop a user-friendly bidirectional charger to more accurately represent vehicle-to-grid (V2G) infrastructure. Smart homes, BEV swap stations and pumped hydroelectric storage can also be researched on future iterations of the SSSG.

  7. Small-scale tunnel test for blast performance

    International Nuclear Information System (INIS)

    Felts, J E; Lee, R J

    2014-01-01

    The data reported here provide a validation of a small-scale tunnel test as a tool to guide the optimization of new explosives for blast performance in tunnels. The small-scale arrangement consisted of a 2-g booster and 10-g sample mounted at the closed end of a 127 mm diameter by 4.6-m long steel tube with pressure transducers along its length. The three performance characteristics considered were peak pressure, initial energy release, and impulse. The relative performance from five explosives was compared to that from a 1.16-m diameter by 30-m long tunnel that used 2.27-kg samples. The peak pressure values didn't correlate between the tunnels. Partial impulse for the explosives did rank similarly. The initial energy release was determined from a one-dimensional point-source analysis, which nearly tracked with impulse suggesting additional energy released further down the tunnel for some explosives. This test is a viable tool for optimizing compositional variations for blast performance in target scenarios of similar geometry.

  8. Cost curves for implantation of small scale hydroelectric power plant project in function of the average annual energy production; Curvas de custo de implantacao de pequenos projetos hidreletricos em funcao da producao media anual de energia

    Energy Technology Data Exchange (ETDEWEB)

    Veja, Fausto Alfredo Canales; Mendes, Carlos Andre Bulhoes; Beluco, Alexandre

    2008-10-15

    Because of its maturity, small hydropower generation is one of the main energy sources to be considered for electrification of areas far from the national grid. Once a site with hydropower potential is identified, technical and economical studies to assess its feasibility shall be done. Cost curves are helpful tools in the appraisal of the economical feasibility of this type of projects. This paper presents a method to determine initial cost curves as a function of the average energy production of the hydropower plant, by using a set of parametric cost curves and the flow duration curve at the analyzed location. The method is illustrated using information related to 18 pre-feasibility studies made in 2002, at the Central-Atlantic rural region of Nicaragua. (author)

  9. 2012 THIN FILM AND SMALL SCALE MECHANICAL BEHAVIOR GRS/GRC, JULY 21-27, 2012

    Energy Technology Data Exchange (ETDEWEB)

    Balk, Thomas

    2012-07-27

    The mechanical behavior of materials with small dimension(s) is of both fundamental scientific interest and technological relevance. The size effects and novel properties that arise from changes in deformation mechanism have important implications for modern technologies such as thin films for microelectronics and MEMS devices, thermal and tribological coatings, materials for energy production and advanced batteries, etc. The overarching goal of the 2012 Gordon Research Conference on "Thin Film and Small Scale Mechanical Behavior" is to discuss recent studies and future opportunities regarding elastic, plastic and time-dependent deformation, as well as degradation and failure mechanisms such as fatigue, fracture and wear. Specific topics of interest include, but are not limited to: fundamental studies of physical mechanisms governing small-scale mechanical behavior; advances in test techniques for materials at small length scales, such as nanotribology and high-temperature nanoindentation; in-situ mechanical testing and characterization; nanomechanics of battery materials, such as swelling-induced phenomena and chemomechanical behavior; flexible electronics; mechanical properties of graphene and carbon-based materials; mechanical behavior of small-scale biological structures and biomimetic materials. Both experimental and computational work will be included in the oral and poster presentations at this Conference.

  10. Emissions from small scale combustion of pelletized wood fuels

    International Nuclear Information System (INIS)

    Bachs, A.

    1998-01-01

    Combustion of wood pellets in small scale heating systems with an effect below 20 kW has increased. During the winter season 1995/96 1500 small plants for heating houses are estimated to be in operation. Stack emissions from three pellet burners and two pellet stoves have been studied at laboratory. Different pellet qualities were tested. When the fraction of fines increased also the NO x emissions increased with about 10 %. As reference fuel 8 mm pellets was used. Tests with 6 mm pellets gave, in most cases, significant lower emissions of CO and THC. Eleven stoves, burners and boilers were studied in a field test. The results show that all the plants generally have higher emissions in the field than during conditions when the plants are adjusted with a stack gas monitoring instrument. A conclusion is that it is difficult for the operator to adjust the plant without a monitoring instrument. The emissions from the tested plants give an estimation of stack gas emissions from small scale pellet plants. The difference between the 'best' and 'worst' technologies is big. The span of emissions with the best technology to the worst is given below. The interval is concerning normal combustion . During abnormal conditions the emissions are on a significant higher level: * CO 80-1 000 mg/MJ; * Tar 0,3-19 mg/MJ; * THC (as methane equivalents) 2-100 mg/MJ; * NO x 50-70 mg/W;, and * Dust emissions 20-40 mg/MJ. Emissions from pellets heating are lower than from wood combustion and the best technology is close to the emission from oil burners. Wood and pellets have the same origin but the conditions to burn them in an environmental friendly way differ. Combustion of pellets could be improved through improved control of the air and fuel ratio that will create more stable conditions for the combustion

  11. Small-scale plasticity critically needs a new mechanics description

    Science.gov (United States)

    Ngan, Alfonso H. W.

    2013-06-01

    Continuum constitutive laws describe the plastic deformation of materials as a smooth, continuously differentiable process. However, provided that the measurement is done with a fine enough resolution, the plastic deformation of real materials is often found to comprise discrete events usually nanometric in size. For bulk-sized specimens, such nanoscale events are minute compared with the specimen size, and so their associated strain changes are negligibly small, and this is why the continuum laws work well. However, when the specimen size is in the micrometer scale or smaller, the strain changes due to the discrete events could be significant, and the continuum description would be highly unsatisfactory. Yet, because of the advent of microtechnology and nanotechnolgy, small-sized materials will be increasingly used, and so there is a strong need to develop suitable replacement descriptions for plasticity of small materials. As the occurrence of the discrete plastic events is also strongly stochastic, their satisfactory description should also be one of a probabilistic, rather than deterministic, nature.

  12. A Novel Multicriteria Evaluation of Small-Scale LNG Supply Alternatives: The Case of Greece

    Directory of Open Access Journals (Sweden)

    Eleni Strantzali

    2018-04-01

    Full Text Available Natural gas as fuel for electricity production has significant advantages, such as the reduction of environmental emissions and the lower operational cost. Due to the flexibility of gas engines, the exploitation of renewable energy sources in an area, can be maximized. The main objective of the present study is to investigate the possibility of LNG supply for sustainable electricity production in insular small-scale electricity systems. A novel multicriteria evaluation model has been developed, based on the methods of Additive Value Model, PROMETHEE and Simos approach. A set of coherent criteria has been selected, that fits perfectly with the demands of this type of problem. The proposed methodology has been implemented in four Greek islands (as they are the most indicative examples and with future perspectives to use natural gas for electricity production and in one power plant in the mainland (as another typical example of small-scale electricity production. The evaluation process included four supply alternatives that cover the annual fuel demands of the examined regions. The obtaining ranking showed that the development of a network supplying individual small-scale terminals in a roundtrip is preferable, compared to the separate supply of each terminal.

  13. Rural electrification in Malaysia via small scale biomass gasifier

    International Nuclear Information System (INIS)

    Zainal Alimuddin Zainal Alauddin

    2000-01-01

    It is the government of Malaysia's vision to see that the rural community is not left behind in its endeavour to be an industrialised nation in the year 2020. The standard of living in the rural areas is very far different from that in the urban areas. To obtain equality the standard of living of the rural folks need to be ungraded. This is done largely by electrification. Electricity has been in the past the catalyst for development and raising the standard of living of the poor. Electricity supplied by the nation's electricity company might not reach all remote areas and therefore there must be a means to provide alternative electrical supply to these places. Present method employ the use of diesel generator sets to provide electricity. The availability of biomass source of supply in the rural areas could be effectively exploited to provide alternative source of energy via a gasification system to run a reciprocating engine coupled to a generator to generated electricity. A small-scale biomass gasification generator set in the range of 2-5 kW is suitable to provide electrical supply to a typical house in the rural area. The present use of biomass source of energy is in its utilisation to provide source of heat for cooking. Several tests have been conducted and the performance is very good. Alternatively another medium scale system generating about 50-20O kW would be suitable for a typical village having about 50 houses. A small-scale system has been developed in USM to provide 5 kW of electrical power. The system used a petrol engine and produces an overall efficiency of 7% with a specific consumption of about 3 kg/kWh. The biomass material used is wood. However for application in the rural areas the biomass material will depend on the type available. A further 50 kW system is being develop in USM. (Author)

  14. Quantum universe on extremely small space-time scales

    International Nuclear Information System (INIS)

    Kuzmichev, V.E.; Kuzmichev, V.V.

    2010-01-01

    The semiclassical approach to the quantum geometrodynamical model is used for the description of the properties of the Universe on extremely small space-time scales. Under this approach, the matter in the Universe has two components of the quantum nature which behave as antigravitating fluids. The first component does not vanish in the limit h → 0 and can be associated with dark energy. The second component is described by an extremely rigid equation of state and goes to zero after the transition to large spacetime scales. On small space-time scales, this quantum correction turns out to be significant. It determines the geometry of the Universe near the initial cosmological singularity point. This geometry is conformal to a unit four-sphere embedded in a five-dimensional Euclidean flat space. During the consequent expansion of the Universe, when reaching the post-Planck era, the geometry of the Universe changes into that conformal to a unit four-hyperboloid in a five-dimensional Lorentzsignatured flat space. This agrees with the hypothesis about the possible change of geometry after the origin of the expanding Universe from the region near the initial singularity point. The origin of the Universe can be interpreted as a quantum transition of the system from a region in the phase space forbidden for the classical motion, but where a trajectory in imaginary time exists, into a region, where the equations of motion have the solution which describes the evolution of the Universe in real time. Near the boundary between two regions, from the side of real time, the Universe undergoes almost an exponential expansion which passes smoothly into the expansion under the action of radiation dominating over matter which is described by the standard cosmological model.

  15. Small-scale fixed wing airplane software verification flight test

    Science.gov (United States)

    Miller, Natasha R.

    The increased demand for micro Unmanned Air Vehicles (UAV) driven by military requirements, commercial use, and academia is creating a need for the ability to quickly and accurately conduct low Reynolds Number aircraft design. There exist several open source software programs that are free or inexpensive that can be used for large scale aircraft design, but few software programs target the realm of low Reynolds Number flight. XFLR5 is an open source, free to download, software program that attempts to take into consideration viscous effects that occur at low Reynolds Number in airfoil design, 3D wing design, and 3D airplane design. An off the shelf, remote control airplane was used as a test bed to model in XFLR5 and then compared to flight test collected data. Flight test focused on the stability modes of the 3D plane, specifically the phugoid mode. Design and execution of the flight tests were accomplished for the RC airplane using methodology from full scale military airplane test procedures. Results from flight test were not conclusive in determining the accuracy of the XFLR5 software program. There were several sources of uncertainty that did not allow for a full analysis of the flight test results. An off the shelf drone autopilot was used as a data collection device for flight testing. The precision and accuracy of the autopilot is unknown. Potential future work should investigate flight test methods for small scale UAV flight.

  16. Formation and fate of marine snow: small-scale processes with large- scale implications

    Directory of Open Access Journals (Sweden)

    Thomas Kiørboe

    2001-12-01

    Full Text Available Marine snow aggregates are believed to be the main vehicles for vertical material transport in the ocean. However, aggregates are also sites of elevated heterotrophic activity, which may rather cause enhanced retention of aggregated material in the upper ocean. Small-scale biological-physical interactions govern the formation and fate of marine snow. Aggregates may form by physical coagulation: fluid motion causes collisions between small primary particles (e.g. phytoplankton that may then stick together to form aggregates with enhanced sinking velocities. Bacteria may subsequently solubilise and remineralise aggregated particles. Because the solubilization rate exceeds the remineralization rate, organic solutes leak out of sinking aggregates. The leaking solutes spread by diffusion and advection and form a chemical trail in the wake of the sinking aggregate that may guide small zooplankters to the aggregate. Also, suspended bacteria may enjoy the elevated concentration of organic solutes in the plume. I explore these small-scale formation and degradation processes by means of models, experiments and field observations. The larger scale implications for the structure and functioning of pelagic food chains of export vs. retention of material will be discussed.

  17. Small-scale microwave background anisotropies implied by large-scale data

    Science.gov (United States)

    Kashlinsky, A.

    1993-01-01

    In the absence of reheating microwave background radiation (MBR) anisotropies on arcminute scales depend uniquely on the amplitude and the coherence length of the primordial density fluctuations (PDFs). These can be determined from the recent data on galaxy correlations, xi(r), on linear scales (APM survey). We develop here expressions for the MBR angular correlation function, C(theta), on arcminute scales in terms of the power spectrum of PDFs and demonstrate their accuracy by comparing with detailed calculations of MBR anisotropies. We then show how to evaluate C(theta) directly in terms of the observed xi(r) and show that the APM data give information on the amplitude, C(O), and the coherence angle of MBR anisotropies on small scales.

  18. Small-Scale Spray Releases: Initial Aerosol Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Mahoney, Lenna A.; Gauglitz, Phillip A.; Kimura, Marcia L.; Brown, Garrett N.; Kurath, Dean E.; Buchmiller, William C.; Smith, Dennese M.; Blanchard, Jeremy; Song, Chen; Daniel, Richard C.; Wells, Beric E.; Tran, Diana N.; Burns, Carolyn A.

    2013-05-29

    One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and net generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of antifoam agents was assessed with most of the simulants. Orifices included round holes and

  19. Small-Scale Spray Releases: Initial Aerosol Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Mahoney, Lenna A.; Gauglitz, Phillip A.; Kimura, Marcia L.; Brown, Garrett N.; Kurath, Dean E.; Buchmiller, William C.; Smith, Dennese M.; Blanchard, Jeremy; Song, Chen; Daniel, Richard C.; Wells, Beric E.; Tran, Diana N.; Burns, Carolyn A.

    2012-11-01

    One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of anti-foam agents was assessed with most of the simulants. Orifices included round holes and

  20. Impact of small-scale storage systems on the photovoltaic penetration potential at the municipal scale

    Science.gov (United States)

    Ramirez Camargo, Luis; Dorner, Wolfgang

    2016-04-01

    The yearly cumulated technical energy generation potential of grid-connected roof-top photovoltaic power plants is significantly larger than the demand of domestic buildings in sparsely populated municipalities in central Europe. However, an energy balance with cumulated annual values does not deliver the right picture about the actual potential for photovoltaics since these run on a highly variable energy source as solar radiation. The mismatch between the periods of generation and demand creates hard limitations for the deployment of the theoretical energy generation potential of roof-top photovoltaics. The actual penetration of roof-top photovoltaic is restricted by the energy quality requirements of the grid and/or the available storage capacity for the electricity production beyond the coverage of own demands. In this study we evaluate in how far small-scale storage systems can contribute to increment the grid-connected roof-top photovoltaic penetration in domestic buildings at a municipal scale. To accomplish this, we calculate, in a first step, the total technical roof-top photovoltaic energy generation potential of a municipality in a high spatiotemporal resolution using a procedure that relies on geographic information systems. Posteriorly, we constrain the set of potential photovoltaic plants to the ones that would be necessary to cover the total yearly demand of the municipality. We assume that photovoltaic plants with the highest yearly yield are the ones that should be installed. For this sub-set of photovoltaic plants we consider five scenarios: 1) no storage 2) one 7 kWh battery is installed in every building with a roof-top photovoltaic plant 3) one 10 kWh battery is installed in every building with a roof-top photovoltaic plant 4) one 7 kWh battery is installed in every domestic building in the municipality 5) one 10 kWh battery is installed in every domestic building in the municipality. Afterwards we evaluate the energy balance of the

  1. In-situ burning of Orimulsion : small scale burns

    International Nuclear Information System (INIS)

    Fingas, M.F.

    2002-01-01

    This study examined the feasibility of burning Orimulsion. In-situ burning has always been a viable method for cleaning oil spills on water because it can effectively reduce the amount of spilled oil and eliminate the need to collect, store, transport and dispose of recovered oil. Orimulsion, however, behaves very differently from conventional oil when it is spilled because of its composition of 70 per cent bitumen in 30 per cent water. In-situ burning of this surfactant-stablized oil-in-water emulsion has never been seriously considered because of the perception that Orimulsion could not be ignited, and if it could, ignition would not be sustained. In this study, burn tests were conducted on 3 scales in a Cleveland Open Cup apparatus of 5 cm, 10 cm and 50 cm diameters. Larger scale burns were conducted in specially built pans. All tests were conducted on salt water which caused the bitumen to separate from the water. The objective was to determine if sufficient vapours could be generated to ignite the Orimulsion. The study also measured if a sustained flame would result in successful combustion. Both objectives were successfully accomplished. Diesel fuel was used to ignite the Orimulsion in the specially designed pan for large scale combustion. Quantitative removal of Orimulsion was achieved in all cases, but in some burns it was necessary to re-ignite the Orimulsion. It was noted that when Orimulsion burns, some trapped water droplets in the bitumen explode with enough force to extinguish a small flame. This did not occur on large-scale burns. It was concluded that the potential for successful in-situ burning increases with size. It was determined that approximately 1 mm in thickness of diesel fuel is needed to ignite a burn. 5 refs., 3 tabs., 4 figs

  2. Small scale tests on the progressive retreat of soil slopes

    Science.gov (United States)

    Voulgari, Chrysoula; Utili, Stefano; Castellanza, Riccardo

    2015-04-01

    In this paper, the influence due to the presence of cracks on the morphologic evolution of natural cliffs subject to progressive retreat induced by weathering is investigated through small scale laboratory tests. Weathering turns hard rocks into soft rocks that maintain the structure of the intact rocks, but are characterised by higher void ratios and reduced bond strengths; soft rocks are transformed into granular soils generally called residual soils. A number of landslides develop in slopes due to weathering which results in the progressive retrogression of the slope face and the further degradation within the weathering zone. Cracks, that are widely present, can be a result of weathering and they can cause a significant decrease in their stability, as they provide preferential flow channels which increase the soil permeability and decrease the soil strength. The geological models employed until now are mainly empirical. Several researchers have tried to study the stability of slopes through experimental procedures. Centrifuge modelling is widely used to investigate the failure of slopes. Small scale tests are also an important approach, in order to study the behaviour of a slope under certain conditions, such as the existence of water, as they allow the observation of the infiltration processes, the movement of the weathering front, deformation and failure. However, the deformation response of a slope subject to weathering is not yet thoroughly clarified. In this work, a set of experiments were conducted to investigate weathering induced successive landslides. Weathering was applied to the slope model by wetting the slope crest through a rainfall simulator device. The moisture content of the soil during the tests was monitored by soil moisture sensors that were buried inside the slope model. High resolution cameras were recording the behaviour of the slope model. GeoPIV was used to analyse the frames and obtain the deformations of the slope model during the

  3. ''Small'' accelerator, radionuclide and radiopharmaceutical production

    International Nuclear Information System (INIS)

    Ruth, T.J.; Wolf, A.P.

    1978-01-01

    The scope of this discussion is limited to the proton/deuteron accelerators capable of producing the positron emitting isotopes carbon-11, nitrogen-13, oxygen-15, and fluorine-18. Attention is focussed on the production process from the selection of the target gas to the synthesis of the desired radiopharamaceutical

  4. Design report small-scale fuel alcohol plant. Volume 2: Detailed construction information

    Science.gov (United States)

    1980-12-01

    The objectives are to provide potential alcohol producers with a reference design and provide a complete, demonstrated design of a small scale fuel alcohol plant. The plant has the capability for feedstock preparation, cooking, saccharification, fermentation, distillation, by-product dewatering, and process steam generation. An interesting feature is an instrumentation and control system designed to allow the plant to run 24 hours per day with only four hours of operator attention.

  5. Flash hydropyrolysis of coal using a small scale of free fall reactor

    Energy Technology Data Exchange (ETDEWEB)

    Miura, K.; Morozumi, F. [Kyoto University, Kyoto (Japan). Department of Chemical Engineering

    1998-07-01

    A small scale of high-pressure free fall reactor was developed for the flash hydropyrolysis of coal. Taiheiyo coal (a Japanese subbituminous coal) was pyrolysed under a high hydrogen pressure without difficulty by use of this reactor. The effect of gas atmosphere, residence time, pressure, and temperature on the product yield was examined in detail. A flash hydropyrolysis reaction model was developed based on the experimental data, and its validity was examined. 8 refs., 5 figs., 1 tab.

  6. Numerical simulation of small scale soft impact tests

    International Nuclear Information System (INIS)

    Varpasuo, Pentti

    2008-01-01

    This paper describes the small scale soft missile impact tests. The purpose of the test program is to provide data for the calibration of the numerical simulation models for impact simulation. In the experiments, both dry and fluid filled missiles are used. The tests with fluid filled missiles investigate the release speed and the droplet size of the fluid release. This data is important in quantifying the fire hazard of flammable liquid after the release. The spray release velocity and droplet size are also input data for analytical and numerical simulation of the liquid spread in the impact. The behaviour of the impact target is the second investigative goal of the test program. The response of reinforced and pre-stressed concrete walls is studied with the aid of displacement and strain monitoring. (authors)

  7. Small-Scale Pellet Boiler with Thermoelectric Generator

    Energy Technology Data Exchange (ETDEWEB)

    Moser, Wilhelm; Friedl, Guenther; Haslinger, Walter [Austrian Bioenergy Centre GmbH, Wieselburg (Austria); Hofbauer, Hermann [Vienna Univ. of Technology (Austria). Inst. of Chemical Engineering

    2006-07-15

    Pellet burners need auxiliary electrical power to provide CO{sub 2}-balanced heat in a comfortable and environment-friendly way. The idea is to produce this and some extra electricity within the furnace in order to save resources and to gain operation reliability and independency. Thermoelectric generators (TEGs) allow the direct conversion of heat to electrical power to a certain extent. They have the advantages of a maintenance-free long life and soundless operation without moving parts or any working fluid. A novel kind of decentralised small-scale biomass-based combined heat and power generation will be developed. The basic system allows grid-independent operation of automatically running biomass furnaces including fuel delivery from storage and circulating the cooling respectively heating water or air. The advanced system also provides electricity for network supply or for other electrical devices and is an additional benefit.

  8. Small-scale wind power design, analysis, and environmental impacts

    CERN Document Server

    Abraham, John P

    2014-01-01

    In today's world, clean and robust energy sources are being sought to provide power to residences, commercial operations, and manufacturing enterprises. Among the most appealing energy sources is wind power-with its high reliability and low environmental impact. Wind power's rapid penetration into markets throughout the world has taken many forms, and this book discusses the types of wind power, as well as the appropriate decisions that need to be made regarding wind power design, testing, installation, and analysis. Inside, the authors detail the design of various small-wind systems including horizontal-axis wind turbines (HAWTs) and vertical-axis wind turbines (VAWTs). The design of wind turbines takes advantage of many avenues of investigation, all of which are included in the book. Analytical methods that have been developed over the past few decades are major methods used for design. Alternatively, experimentation (typically using scaled models in wind tunnels) and numerical simulation (using modern comp...

  9. Small scale renewable solar energy and the best result project

    Energy Technology Data Exchange (ETDEWEB)

    Bilbao, J.; Miguel, A.H.; Perez-Burgos, A.M. [Valladolid Univ. (Spain)

    2008-07-01

    The European Community has established programmes with different Projects in relation with the develop of an energy system according to de Kyoto objectives, improving energy efficiency, maintaining security supply and doubling the share of renewable energy use. The Best Result Project (Building and Energy Systems and Technology in Renewable Energy Sources Update and Linked Training), is financed by the European Commission, Intelligent Energy Agency (EIE) and the project objectives are to develop training and diffusion activities in the field of Renewable Energy Technology. The project aims to raise the renewable energy knowledge among suppliers and general public. The project activities are: basis and specialized training events, workshops, meetings, visits and e-learning common platform. The final objective is to extend the market of small scale RES applications in the building and energy sector through common and local activities addressing RES suppliers and consumers. (orig.)

  10. Optimal Combustion Conditions for a Small-scale Biomass Boiler

    Directory of Open Access Journals (Sweden)

    Viktor Plaček

    2012-01-01

    Full Text Available This paper reports on an attempt to achieve maximum efficiency and lowest possible emissions for a small-scale biomass boiler. This aim can be attained only by changing the control algorithm of the boiler, and in this way not raising the acquisition costs for the boiler. This paper describes the experimental facility, the problems that arose while establishing the facility, and how we have dealt with them. The focus is on discontinuities arising after periodic grate sweeping, and on finding the parameters of the PID control loops. Alongside these methods, which need a lambda probe signal for proper functionality, we inroduce another method, which is able to intercept the optimal combustion working point without the need to use a lambda sensor.

  11. Emissions from small scale biomass combustion - Research needs

    International Nuclear Information System (INIS)

    Gustavsson, L.; Karlsson, M.L.; Larfeldt, J.; Leckner, B.

    1994-01-01

    Earlier investigations have shown that small scale biomass combustion leads to unacceptable emissions in the air. The most important problem is high levels of unburnt hydrocarbons. This report analyzes which are the most important reasons to these emissions and which research efforts that are necessary to increase the knowledge about the combustion processes, thereby promoting the development of environmentally feasible equipment. The following factors are defined as most crucial to emission levels: size of combustion chamber, air excess ratio, means of combustion air supply, mixing between air and fuel, transient events, and fuel quality. It is concluded that both basic and research within the area is needed. More specific, research in the form of systematic analysis of best available technology, reactor experiments, compilation of knowledge about relevant basic combustion processes, mathematical modelling as well as development of measurement techniques are called for. 15 refs, 11 figs, 1 tab

  12. Massive Boson Production at Small qT in Soft-Collinear Effective Theory

    Science.gov (United States)

    Becher, Thomas; Neubert, Matthias; Wilhelm, Daniel

    2013-01-01

    We study the differential cross sections for electroweak gauge-boson and Higgs production at small and very small transverse-momentum qT. Large logarithms are resummed using soft-collinear effective theory. The collinear anomaly generates a non-perturbative scale q*, which protects the processes from receiving large long-distance hadronic contributions. A numerical comparison of our predictions with data on the transverse-momentum distribution in Z-boson production at the Tevatron and LHC is given.

  13. Analysis of small scale turbulent structures and the effect of spatial scales on gas transfer

    Science.gov (United States)

    Schnieders, Jana; Garbe, Christoph

    2014-05-01

    The exchange of gases through the air-sea interface strongly depends on environmental conditions such as wind stress and waves which in turn generate near surface turbulence. Near surface turbulence is a main driver of surface divergence which has been shown to cause highly variable transfer rates on relatively small spatial scales. Due to the cool skin of the ocean, heat can be used as a tracer to detect areas of surface convergence and thus gather information about size and intensity of a turbulent process. We use infrared imagery to visualize near surface aqueous turbulence and determine the impact of turbulent scales on exchange rates. Through the high temporal and spatial resolution of these types of measurements spatial scales as well as surface dynamics can be captured. The surface heat pattern is formed by distinct structures on two scales - small-scale short lived structures termed fish scales and larger scale cold streaks that are consistent with the footprints of Langmuir Circulations. There are two key characteristics of the observed surface heat patterns: 1. The surface heat patterns show characteristic features of scales. 2. The structure of these patterns change with increasing wind stress and surface conditions. In [2] turbulent cell sizes have been shown to systematically decrease with increasing wind speed until a saturation at u* = 0.7 cm/s is reached. Results suggest a saturation in the tangential stress. Similar behaviour has been observed by [1] for gas transfer measurements at higher wind speeds. In this contribution a new model to estimate the heat flux is applied which is based on the measured turbulent cell size und surface velocities. This approach allows the direct comparison of the net effect on heat flux of eddies of different sizes and a comparison to gas transfer measurements. Linking transport models with thermographic measurements, transfer velocities can be computed. In this contribution, we will quantify the effect of small scale

  14. Investigation of small break loss-of-coolant phenomena in a small scale nonnuclear test facility

    International Nuclear Information System (INIS)

    Cozzuol, J.M.; Fauble, T.J.; Harvego, E.A.

    1980-01-01

    A small-scale nonnuclear integral test facility designed to simulate a pressurized water reactor (PWR) system was used to evaluate the effects of a small break loss-of-coolant accident (LOCA) on the system thermal-hydraulic response. The experiment approximated a 2.5% (11-cm diameter) communicative break in the cold leg of a PWR, and included initial conditions which were similar to conditions in a PWR operating at full power. The 2.5% break size ensured that the nominal break flow rate was greater than the high pressure injection system (HPIS) flow rate, thus providing the potential for a continuous system depressurization. The sequence of events was similar to that used in evaluation model analysis of small break loss-of-coolant accidents, and included simulated reactor scram and loss of offsite power. Comparisions of experimental data with computer code calculations are used to demonstrate the capabilities and limitations of integral system calculations used to predict phenomena which can be important in the assessment of a small break LOCA in a PWR

  15. Evaluation of remotely sensed actual evapotranspiration data for modeling small scale irrigation in Ethiopia.

    Science.gov (United States)

    Taddele, Y. D.; Ayana, E.; Worqlul, A. W.; Srinivasan, R.; Gerik, T.; Clarke, N.

    2017-12-01

    The research presented in this paper is conducted in Ethiopia, which is located in the horn of Africa. Ethiopian economy largely depends on rainfed agriculture, which employs 80% of the labor force. The rainfed agriculture is frequently affected by droughts and dry spells. Small scale irrigation is considered as the lifeline for the livelihoods of smallholder farmers in Ethiopia. Biophysical models are highly used to determine the agricultural production, environmental sustainability, and socio-economic outcomes of small scale irrigation in Ethiopia. However, detailed spatially explicit data is not adequately available to calibrate and validate simulations from biophysical models. The Soil and Water Assessment Tool (SWAT) model was setup using finer resolution spatial and temporal data. The actual evapotranspiration (AET) estimation from the SWAT model was compared with two remotely sensed data, namely the Advanced Very High Resolution Radiometer (AVHRR) and Moderate Resolution Imaging Spectrometer (MODIS). The performance of the monthly satellite data was evaluated with correlation coefficient (R2) over the different land use groups. The result indicated that over the long term and monthly the AVHRR AET captures the pattern of SWAT simulated AET reasonably well, especially on agricultural dominated landscapes. A comparison between SWAT simulated AET and AVHRR AET provided mixed results on grassland dominated landscapes and poor agreement on forest dominated landscapes. Results showed that the AVHRR AET products showed superior agreement with the SWAT simulated AET than MODIS AET. This suggests that remotely sensed products can be used as valuable tool in properly modeling small scale irrigation.

  16. Small-Scale Fabrication of Biomimetic Structures for Periodontal Regeneration

    Science.gov (United States)

    Green, David W.; Lee, Jung-Seok; Jung, Han-Sung

    2016-01-01

    The periodontium is the supporting tissues for the tooth organ and is vulnerable to destruction, arising from overpopulating pathogenic bacteria and spirochaetes. The presence of microbes together with host responses can destroy large parts of the periodontium sometimes leading tooth loss. Permanent tissue replacements are made possible with tissue engineering techniques. However, existing periodontal biomaterials cannot promote proper tissue architectures, necessary tissue volumes within the periodontal pocket and a “water-tight” barrier, to become clinically acceptable. New kinds of small-scale engineered biomaterials, with increasing biological complexity are needed to guide proper biomimetic regeneration of periodontal tissues. So the ability to make compound structures with small modules, filled with tissue components, is a promising design strategy for simulating the anatomical complexity of the periodotium attachment complexes along the tooth root and the abutment with the tooth collar. Anatomical structures such as, intima, adventitia, and special compartments such as the epithelial cell rests of Malassez or a stellate reticulum niche need to be engineered from the start of regeneration to produce proper periodontium replacement. It is our contention that the positioning of tissue components at the origin is also necessary to promote self-organizing cell–cell connections, cell–matrix connections. This leads to accelerated, synchronized and well-formed tissue architectures and anatomies. This strategy is a highly effective preparation for tackling periodontitis, periodontium tissue resorption, and to ultimately prevent tooth loss. Furthermore, such biomimetic tissue replacements will tackle problems associated with dental implant support and perimimplantitis. PMID:26903872

  17. Small-Scale Fabrication of Biomimetic Structures for Periodontal Regeneration

    Directory of Open Access Journals (Sweden)

    David William Green

    2016-02-01

    Full Text Available The periodontium is the supporting tissues for the tooth organ and is vulnerable to destruction, arising from overpopulating pathogenic bacteria and spirochaetes. The presence of microbes together with host responses can destroy large parts of the periodontium sometimes leading tooth loss. Permanent tissue replacements are made possible with tissue engineering techniques. However, existing periodontal biomaterials cannot promote proper tissue architectures, necessary tissue volumes within the periodontal pocket and a water-tight barrier, to become clinically acceptable. New kinds of small-scale engineered biomaterials, with increasing biological complexity are needed to guide proper biomimetic regeneration of periodontal tissues. So the ability to make compound structures with small modules, filled with tissue components, is a promising design strategy for simulating the anatomical complexity of the periodotium attachement complexes along the tooth root and the abutment with the tooth collar. Anatomical structures such as, intima, adventitia and special compartments such as the epithelial cell rests of Malassez or a stellate reticulum niche need to be engineered from the start of regeneration to produce proper periodontium replacement.. It is our contention that the positioning of tissue components at the origin is also necessary to promote self-organising cell-cell connections, cell-matrix connections. This leads to accelerated, synchronized and well-formed tissue architectures and anatomies. This strategy is a highly effective preparation for tackling periodontitis, periodontium tissue resorption and to ultimately prevent tooth loss. Furthermore, such biomimetic tissue replacements will tackle problems associated with dental implant support and perimimplantitis.

  18. Hydropower harvesting from a small scale reciprocating system

    Energy Technology Data Exchange (ETDEWEB)

    Malla, Ramesh B.; Shrestha, Binu; Bagtzoglou, Amvrossios; Drasdis, Jonathon [Department of Civil and Environmental Engineering, University of Connecticut, 261 Glenbrook Road, Storrs, CT 06269-2037 (United States); Johnson, Paul [eGen LLC, 1084 Shennecossett Road, Groton, CT 06340 (United States)

    2011-05-15

    Conventional hydropower systems that can take advantage of low head movement of water require substantial flow rates. However, these systems cannot harvest hydro energy from small sources of water with low head and low discharge, such as streams and creeks. The reciprocating hydropower system discussed in this paper can harvest power from such low flow discharge and low head sources. This paper presents a detailed proof-of-concept study of the hydropower model, including the underlining theoretical principles. Laboratory test results demonstrating the dependence of the lift force in the reciprocating small scale hydropower model as a function of flow velocity, size and rotational speed of the cylinder and comparison of the results with a previous study are also included. Two methods of power harvesting from the output displacement obtained from the hydropower system are discussed. The first employs electromagnetic induction principles and the other is based on a linear inertial generator using a conventional second order spring mass damper system. Finally, results from a finite element analysis of the hydropower system are presented and facilitate future design of the structural aspects of the housing for the reciprocating cylinder. (author)

  19. Social Norms of Cooperation in Small-Scale Societies.

    Directory of Open Access Journals (Sweden)

    Fernando P Santos

    2016-01-01

    Full Text Available Indirect reciprocity, besides providing a convenient framework to address the evolution of moral systems, offers a simple and plausible explanation for the prevalence of cooperation among unrelated individuals. By helping someone, an individual may increase her/his reputation, which may change the pre-disposition of others to help her/him in the future. This, however, depends on what is reckoned as a good or a bad action, i.e., on the adopted social norm responsible for raising or damaging a reputation. In particular, it remains an open question which social norms are able to foster cooperation in small-scale societies, while enduring the wide plethora of stochastic affects inherent to finite populations. Here we address this problem by studying the stochastic dynamics of cooperation under distinct social norms, showing that the leading norms capable of promoting cooperation depend on the community size. However, only a single norm systematically leads to the highest cooperative standards in small communities. That simple norm dictates that only whoever cooperates with good individuals, and defects against bad ones, deserves a good reputation, a pattern that proves robust to errors, mutations and variations in the intensity of selection.

  20. Social Norms of Cooperation in Small-Scale Societies.

    Science.gov (United States)

    Santos, Fernando P; Santos, Francisco C; Pacheco, Jorge M

    2016-01-01

    Indirect reciprocity, besides providing a convenient framework to address the evolution of moral systems, offers a simple and plausible explanation for the prevalence of cooperation among unrelated individuals. By helping someone, an individual may increase her/his reputation, which may change the pre-disposition of others to help her/him in the future. This, however, depends on what is reckoned as a good or a bad action, i.e., on the adopted social norm responsible for raising or damaging a reputation. In particular, it remains an open question which social norms are able to foster cooperation in small-scale societies, while enduring the wide plethora of stochastic affects inherent to finite populations. Here we address this problem by studying the stochastic dynamics of cooperation under distinct social norms, showing that the leading norms capable of promoting cooperation depend on the community size. However, only a single norm systematically leads to the highest cooperative standards in small communities. That simple norm dictates that only whoever cooperates with good individuals, and defects against bad ones, deserves a good reputation, a pattern that proves robust to errors, mutations and variations in the intensity of selection.

  1. A review on technology maturity of small scale energy storage technologies★

    Directory of Open Access Journals (Sweden)

    Nguyen Thu-Trang

    2017-01-01

    Full Text Available This paper reviews the current status of energy storage technologies which have the higher potential to be applied in small scale energy systems. Small scale energy systems can be categorized as ones that are able to supply energy in various forms for a building, or a small area, or a limited community, or an enterprise; typically, they are end-user systems. Energy storage technologies are classified based on their form of energy stored. A two-step evaluation is proposed for selecting suitable storage technologies for small scale energy systems, including identifying possible technical options, and addressing techno-economic aspects. Firstly, a review on energy storage technologies at small scale level is carried out. Secondly, an assessment of technology readiness level (TRL is conducted. The TRLs are ranked according to information gathered from literature review. Levels of market maturity of the technologies are addressed by taking into account their market development stages through reviewing published materials. The TRLs and the levels of market maturity are then combined into a technology maturity curve. Additionally, market driving factors are identified by using different stages in product life cycle. The results indicate that lead-acid, micro pumped hydro storage, NaS battery, NiCd battery, flywheel, NaNiCl battery, Li-ion battery, and sensible thermal storage are the most mature technologies for small scale energy systems. In the near future, hydrogen fuel cells, thermal storages using phase change materials and thermochemical materials are expected to become more popular in the energy storage market.

  2. Latent hardening size effect in small-scale plasticity

    Science.gov (United States)

    Bardella, Lorenzo; Segurado, Javier; Panteghini, Andrea; Llorca, Javier

    2013-07-01

    We aim at understanding the multislip behaviour of metals subject to irreversible deformations at small-scales. By focusing on the simple shear of a constrained single-crystal strip, we show that discrete Dislocation Dynamics (DD) simulations predict a strong latent hardening size effect, with smaller being stronger in the range [1.5 µm, 6 µm] for the strip height. We attempt to represent the DD pseudo-experimental results by developing a flow theory of Strain Gradient Crystal Plasticity (SGCP), involving both energetic and dissipative higher-order terms and, as a main novelty, a strain gradient extension of the conventional latent hardening. In order to discuss the capability of the SGCP theory proposed, we implement it into a Finite Element (FE) code and set its material parameters on the basis of the DD results. The SGCP FE code is specifically developed for the boundary value problem under study so that we can implement a fully implicit (Backward Euler) consistent algorithm. Special emphasis is placed on the discussion of the role of the material length scales involved in the SGCP model, from both the mechanical and numerical points of view.

  3. Latent hardening size effect in small-scale plasticity

    International Nuclear Information System (INIS)

    Bardella, Lorenzo; Panteghini, Andrea; Segurado, Javier; Llorca, Javier

    2013-01-01

    We aim at understanding the multislip behaviour of metals subject to irreversible deformations at small-scales. By focusing on the simple shear of a constrained single-crystal strip, we show that discrete Dislocation Dynamics (DD) simulations predict a strong latent hardening size effect, with smaller being stronger in the range [1.5 µm, 6 µm] for the strip height. We attempt to represent the DD pseudo-experimental results by developing a flow theory of Strain Gradient Crystal Plasticity (SGCP), involving both energetic and dissipative higher-order terms and, as a main novelty, a strain gradient extension of the conventional latent hardening. In order to discuss the capability of the SGCP theory proposed, we implement it into a Finite Element (FE) code and set its material parameters on the basis of the DD results. The SGCP FE code is specifically developed for the boundary value problem under study so that we can implement a fully implicit (Backward Euler) consistent algorithm. Special emphasis is placed on the discussion of the role of the material length scales involved in the SGCP model, from both the mechanical and numerical points of view. (paper)

  4. Small-Scale Experiments.10-gallon drum experiment summary

    Energy Technology Data Exchange (ETDEWEB)

    Rosenberg, David M.

    2015-02-05

    A series of sub-scale (10-gallon) drum experiments were conducted to characterize the reactivity, heat generation, and gas generation of mixtures of chemicals believed to be present in the drum (68660) known to have breached in association with the radiation release event at the Waste Isolation Pilot Plant (WIPP) on February 14, 2014, at a scale expected to be large enough to replicate the environment in that drum but small enough to be practical, safe, and cost effective. These tests were not intended to replicate all the properties of drum 68660 or the event that led to its breach, or to validate a particular hypothesis of the release event. They were intended to observe, in a controlled environment and with suitable diagnostics, the behavior of simple mixtures of chemicals in order to determine if they could support reactivity that could result in ignition or if some other ingredient or event would be necessary. There is a significant amount of uncertainty into the exact composition of the barrel; a limited sub-set of known components was identified, reviewed with Technical Assessment Team (TAT) members, and used in these tests. This set of experiments was intended to provide a framework to postulate realistic, data-supported hypotheses for processes that occur in a “68660-like” configuration, not definitively prove what actually occurred in 68660.

  5. Small-Scale Testing of Laterally Loaded Monopiles in Sand

    DEFF Research Database (Denmark)

    Thomassen, Kristina; Roesen, Hanne Ravn; Ibsen, Lars Bo

    2011-01-01

    of small-scale laboratory tests. Six quasi-static tests are conducted on piles with diameters of 40mm and 100mm and a slenderness ratio, L/D, of 5. To minimise scale effects, the tests are carried out in a pressure tank at various stress levels. From the obtained load-deflection relationships......In current designs of offshore wind turbines, monopiles are often used as foundation. The behaviour of the monopoles when subjected to lateral loading has not been fully investigated. In this paper, the behaviour of two non-slender piles in sand subjected to lateral loading are analysed by means...... it is revealed that the uncertainties of the results for the pile with a diameter of 40mm are large. The load-deflection relationships normalised as H/(L2Dγ’) and y/D indicate that the lateral load, H, is proportional to L2D. Comparison of the normalised load-deflection relationships for different stress levels...

  6. Small-scale dislocation plasticity in strontium titanate

    Energy Technology Data Exchange (ETDEWEB)

    Stukowski, Alexander; Javaid, Farhan; Durst, Karsten; Albe, Karsten [Technische Universitaet Darmstadt (Germany)

    2016-07-01

    Strontium titanate (STO) is an optically transparent perovskite oxide ceramic material. In contrast to other ceramics, single crystal STO plastically deforms under ambient condition, without showing a phase transition or early fracture. This remarkable ductility makes it a prime candidate for different technological applications. However, while the mechanical behavior of bulk STO has been studied extensively using uniaxial compression testing techniques, little is known about the local, small-scale behavior and the details of dislocation-based nanoplasticity in this perovskite material. In this contribution we compare results obtained from new nanoindentation experiments and corresponding large-scale molecular dynamics simulations. The evolution of the plastic zone and dislocation structures that form underneath the indenter is investigated using etch-pit methods in experiments and a novel three-dimensional defect identification technique in atomistic computer models. The latter allows tracing the evolution of the complete dislocation line network as function of indentation depth, quantifying the activity of different slip systems, and correlating this information with the recorded load-displacement curves and hardness data.

  7. Structures and Intermittency in Small Scales Solar Wind Turbulence

    International Nuclear Information System (INIS)

    Sahraoui, Fouad; Goldstein, Melvyn

    2010-01-01

    Several observations in space plasmas have reported the presence of coherent structures at different plasma scales. Structure formation is believed to result from nonlinear interactions between the plasma modes, which depend strongly on their phase synchronization. Despite this important role of the phases in turbulence, very limited work has been devoted to study the phases as potential tracers of nonlinearities in comparison with the wealth of literature on power spectra of turbulence where phases are totally missed. The reason why the phases are seldom used is probably because they usually appear to be completely mixed (due to their dependence on an arbitrary time origin and to 2π periodicity). To handle the phases properly, a new method based on using surrogate data has been developed recently to detect coherent structures in magnetized plasmas [Sahraoui, PRE, 2008]. Here, we show new applications of the technique to study the nature (weak vs strong, self-similar vs intermittent) of the small scale turbulence in the solar wind using the Cluster observations.

  8. Small-scale structure in the diffuse interstellar medium

    International Nuclear Information System (INIS)

    Meyer, D.M.

    1990-01-01

    The initial results of a study to probe the small-scale structure in the diffuse interstellar medium (ISM) through IUE and optical observations of interstellar absorption lines toward both components of resolvable binary stars is reported. The binaries (Kappa CrA, 57 Aql, 59 And, HR 1609/10, 19 Lyn, and Theta Ser) observed with IUE have projected linear separations ranging from 5700 to 700 Au. Except for Kappa CrA, the strengths of the interstellar absorption lines toward both components of these binaries agree to within 10 percent. In the case of Kappa CrA, the optically thin interstellar Mg I and Mn II lines are about 50 percent stronger toward Kappa-2 CrA than Kappa-1 CrA. Higher resolution observations of interstellar Ca II show that this difference is concentrated in the main interstellar component at V(LSR) = 9 + or - 2 km/s. Interestingly, this velocity corresponds to an intervening cloud that may be associated with the prominent Loop I shell in the local ISM. Given the separation (23 arcsec) and distance (120 pc) of Kappa CrA, the line strength variations indicate that this cloud has structure on scales of 2800 AU or less. 21 refs

  9. Quantifying seismic anisotropy induced by small-scale chemical heterogeneities

    Science.gov (United States)

    Alder, C.; Bodin, T.; Ricard, Y.; Capdeville, Y.; Debayle, E.; Montagner, J. P.

    2017-12-01

    Observations of seismic anisotropy are usually used as a proxy for lattice-preferred orientation (LPO) of anisotropic minerals in the Earth's mantle. In this way, seismic anisotropy observed in tomographic models provides important constraints on the geometry of mantle deformation associated with thermal convection and plate tectonics. However, in addition to LPO, small-scale heterogeneities that cannot be resolved by long-period seismic waves may also produce anisotropy. The observed (i.e. apparent) anisotropy is then a combination of an intrinsic and an extrinsic component. Assuming the Earth's mantle exhibits petrological inhomogeneities at all scales, tomographic models built from long-period seismic waves may thus display extrinsic anisotropy. In this paper, we investigate the relation between the amplitude of seismic heterogeneities and the level of induced S-wave radial anisotropy as seen by long-period seismic waves. We generate some simple 1-D and 2-D isotropic models that exhibit a power spectrum of heterogeneities as what is expected for the Earth's mantle, that is, varying as 1/k, with k the wavenumber of these heterogeneities. The 1-D toy models correspond to simple layered media. In the 2-D case, our models depict marble-cake patterns in which an anomaly in shear wave velocity has been advected within convective cells. The long-wavelength equivalents of these models are computed using upscaling relations that link properties of a rapidly varying elastic medium to properties of the effective, that is, apparent, medium as seen by long-period waves. The resulting homogenized media exhibit extrinsic anisotropy and represent what would be observed in tomography. In the 1-D case, we analytically show that the level of anisotropy increases with the square of the amplitude of heterogeneities. This relation is numerically verified for both 1-D and 2-D media. In addition, we predict that 10 per cent of chemical heterogeneities in 2-D marble-cake models can

  10. Controls on sublithospheric small-scale convection on Curie depths

    Science.gov (United States)

    Likerman, Jeremias; Zlotnik, Sergio; Chun-Feng, Li

    2017-04-01

    As the ocean lithosphere cools and thickens, its bottom layer goes unstable leading to sub-lithospheric small-scale convection (SSC). Since SSC was originally proposed, there have been considerable efforts regarding the understanding of the physics that rules the thermal instabilities of the SSC (e.g. Dumoulin et al, 1999; Solomatov and Moresi, 2000). Over the last several years, it is understood that the interaction between the plate movement and the SSC tends to form longitudinal (LRs or also called 'Richter rolls') and transverse rolls (TRs), of which the axis is parallel and perpendicular to the plate motion, respectively. The geometry of these rolls have been been recently inferred by Li et al (2013) using Curie depths from the North Atlantic as proxies for plates temperatures. They showed that Curie depths have a large oscillating and heterogeneous patterns that could be related to SSC. In the North Atlantic transverse rolls seem predominant. In this work we analyze, by means of 3D dynamical numerical simulations, the influence of SSC on the Curie depths patterns observed in the North Atlantic and Pacific plates. We investigate the behaviour of the Curie isotherms trying to determine if SSC is able to reproduce the observed data, and the influence of several poorly constrained rheological parameters. Our numerical simulations show that: a) using realistic laboratory-constrained rheologies and temperature it is possible to modify temperatures as low as those at Curie depths; b) transverse rolls are generated as well as longitudinal rolls on those isotherms; c) the spreading rate is a first order control on the developing of transverse rolls. References Dumoulin, C., Doin, M. P., & Fleitout, L. (1999). Heat transport in stagnant lid convection with temperature-and pressure-dependent Newtonian or non-Newtonian rheology. Journal of Geophysical Research: Solid Earth, 104(B6), 12759-12777. Li, C. F., Wang, J., Lin, J., & Wang, T. (2013). Thermal evolution of the

  11. Intelligent Network Flow Optimization (INFLO) prototype : Seattle small-scale demonstration report.

    Science.gov (United States)

    2015-05-01

    This report describes the performance and results of the INFLO Prototype Small-Scale Demonstration. The purpose of : the Small-Scale Demonstration was to deploy the INFLO Prototype System to demonstrate its functionality and : performance in an opera...

  12. design of a small scale wind generator for low wind speed areas

    African Journals Online (AJOL)

    USER

    Most small scale level wind turbine generators are directly driven system, variable speed, and partially ... the best solutions for small-scale wind power plants. Low-speed multi-pole PM generators ..... Designs of the Same Magnet Structure for.

  13. Responsible tourism: A guide for tourism and sustainability in small-scale fisheries and agri-food

    OpenAIRE

    Ford, Adriana; Acott, Timothy

    2015-01-01

    ‘Responsible Tourism: a guide for tourism and sustainability in small-scale fisheries and agri-food’ is a product of TourFish, a project funded by the EU INTERREG IVA 2 Seas programme. The aim of TourFish was to explore opportunities for coastal areas through developing responsible tourism that draws together food, small-scale inshore fisheries, regional branding and place-based marketing opportunities.

  14. Social innovation to promote sustainability and independence of small-scale palm oil farmers in the Province of Jambi, Indonesia

    OpenAIRE

    Firman, Anita Nathalia

    2017-01-01

    The aim of this thesis was to investigate the situation of the independent small-scale palm oil farmers in the Province of Jambi, Indonesia regarding the practices of palm oil production that cause deforestation in Sumatra. The goal of this thesis was to provide sustainable opportunities for the independent small-scale farmers in Jambi through social innovation. The field research took place at the village of Mekar Jaya and Sungai Rotan Village in the Provinces of Jambi, Indonesia. In the fra...

  15. Small Scale Yielding Correction of Constraint Loss in Small Sized Fracture Toughness Test Specimens

    International Nuclear Information System (INIS)

    Kim, Maan Won; Kim, Min Chul; Lee, Bong Sang; Hong, Jun Hwa

    2005-01-01

    Fracture toughness data in the ductile-brittle transition region of ferritic steels show scatter produced by local sampling effects and specimen geometry dependence which results from relaxation in crack tip constraint. The ASTM E1921 provides a standard test method to define the median toughness temperature curve, so called Master Curve, for the material corresponding to a 1T crack front length and also defines a reference temperature, T 0 , at which median toughness value is 100 MPam for a 1T size specimen. The ASTM E1921 procedures assume that high constraint, small scaling yielding (SSY) conditions prevail at fracture along the crack front. Violation of the SSY assumption occurs most often during tests of smaller specimens. Constraint loss in such cases leads to higher toughness values and thus lower T 0 values. When applied to a structure with low constraint geometry, the standard fracture toughness estimates may lead to strongly over-conservative estimates. A lot of efforts have been made to adjust the constraint effect. In this work, we applied a small-scale yielding correction (SSYC) to adjust the constraint loss of 1/3PCVN and PCVN specimens which are relatively smaller than 1T size specimen at the fracture toughness Master Curve test

  16. Small Scale Irrigation within Water, Energy and Food Nexus Framework in Ethiopia.

    Science.gov (United States)

    Gerik, T.; Worqlul, A. W.; Yihun, D.; Bizimana, J. C.; Jeong, J.; Schmitter, P.; Srinivasan, R.; Richardson, J. W.; Clark, N.

    2017-12-01

    This study presents the nexus of food, energy and water framework in the context of small scale irrigation for vegetable production during the dry season in an irrigated agriculture system in Ethiopia. The study is based on detailed data collected in three sites of the Innovation Lab for Small Scale Irrigation (ILSSI) project in Ethiopia. The sites were Robit, Dangishta and Lemo and detailed field data was collected in 18 households in each site. The field data collected includes crop management (such as irrigation amount and dates, fertilizer rates, tillage practices, irrigation technologies, etc.) and agricultural production (crop yield, biomass, etc.) on tomato, onion and cabbage during the dry season. Four different water lifting technologies - namely rope with pulley and bucket, rope and washer pump, solar pump and motor pump - were used for water withdrawal from shallow groundwater wells. The Soil and Water Assessment Tool (SWAT) and Agricultural Policy Environmental eXtender (APEX) models were used in an integrated manner to assess water resource potential and develop water use efficiency of vegetables, which is a relationship between amount of water applied and vegetable yield. The water use efficiency for each vegetable crops were translated into energy requirement as pumping hours and potential irrigable areas for the water lifting technologies. This integrated approach was found useful to optimize water and energy use for sustainable food production using small scale irrigation. The holistic approach will not only provide a significant contribution to achieving food self-sufficiency, but will also be effective for optimizing agricultural input. Keyword: small scale irrigation, integrated modeling, water lifting technology, East Africa

  17. Evaluation of measurement uncertainty for purity of a monoterpenic acid by small-scale coulometry

    Science.gov (United States)

    Norte, L. C.; de Carvalho, E. M.; Tappin, M. R. R.; Borges, P. P.

    2018-03-01

    Purity of the perylic acid (HPe) which is a monoterpenic acid from natural product (NP) with anti-inflammatory and anticancer properties was analyzed by small-scale coulometry (SSC), due to the low availability of HPe on the pharmaceutic market and its high cost. This work aims to present the evaluation of the measurements uncertainty from the purity of HPe by using SSC. Coulometric mean of purity obtained from 5 replicates resulted in 94.23% ± 0.88% (k = 2.06, for an approximately 95% confidence level). These studies aim in the future to develop the production of certified reference materials from NPs.

  18. Employee turnover and productivity among small business entities in Nigeria

    Directory of Open Access Journals (Sweden)

    John N. N. Ugoani

    2016-12-01

    Full Text Available This study was designed to evaluate the problems of employee turnover on productivity among small business entities in Nigeria, and recommend remedial actions. Employee turnover is the separation of employees from employers and replacement with other employees. Productive manpower is a critical element for the economic survival of any small business entity. The survey research design was used for the study. The sample comprised of 320 respondents. Data generated were analyzed by using descriptive, and Z-test statistical techniques. It was found that employee turnover adversely affects productivity in small business entities.

  19. Scaling production and improving efficiency in DEA: an interactive approach

    Science.gov (United States)

    Rödder, Wilhelm; Kleine, Andreas; Dellnitz, Andreas

    2017-10-01

    DEA models help a DMU to detect its (in-)efficiency and to improve activities, if necessary. Efficiency is only one economic aim for a decision-maker; however, up- or downsizing might be a second one. Improving efficiency is the main topic in DEA; the long-term strategy towards the right production size should attract our attention as well. Not always the management of a DMU primarily focuses on technical efficiency but rather is interested in gaining scale effects. In this paper, a formula for returns to scale (RTS) is developed, and this formula is even applicable for interior points of technology. Particularly, technical and scale inefficient DMUs need sophisticated instruments to improve their situation. Considering RTS as well as efficiency, in this paper, we give an advice for each DMU to find an economically reliable path from its actual situation to better activities and finally to most productive scale size (mpss), perhaps. For realizing this path, we propose an interactive algorithm, thus harmonizing the scientific findings and the interests of the management. Small numerical examples illustrate such paths for selected DMUs; an empirical application in theatre management completes the contribution.

  20. LHC Report: Production and small angles

    CERN Multimedia

    Jan Uythoven for the LHC team

    2012-01-01

    The last two weeks have seen steady luminosity production. The total luminosity of ATLAS and CMS exceeded 19 fb-1, while LHCb reached 1.8 fb-1 and ALICE, 6 pb-1.   As reported in previous LHC reports, the continuous running with large beam intensities is resulting in beam-induced heating of certain elements, such as the synchrotron light monitor (BSRT), the ALFA detector and the injection kicker magnets. These first two elements had shown a sudden increase in temperature in the previous weeks - but only for the components that are on the counter-clockwise rotating beam. By making slight changes to the radiofrequency parameters, which affect the bunch length, the power spectrum of the beam was changed. This significantly reduced the observed heating of the BSRT and the ALFA detector. Another improvement was recently made to the measurement process of the number of transverse oscillations of the beam in one turn, known as the “betatron tune”. The frequency of the betatron tune ...

  1. ARCADE small-scale docking mechanism for micro-satellites

    Science.gov (United States)

    Boesso, A.; Francesconi, A.

    2013-05-01

    The development of on-orbit autonomous rendezvous and docking (ARD) capabilities represents a key point for a number of appealing mission scenarios that include activities of on-orbit servicing, automated assembly of modular structures and active debris removal. As of today, especially in the field of micro-satellites ARD, many fundamental technologies are still missing or require further developments and micro-gravity testing. In this framework, the University of Padova, Centre of Studies and Activities for Space (CISAS), developed the Autonomous Rendezvous Control and Docking Experiment (ARCADE), a technology demonstrator intended to fly aboard a BEXUS stratospheric balloon. The goal was to design, build and test, in critical environment conditions, a proximity relative navigation system, a custom-made reaction wheel and a small-size docking mechanism. The ARCADE docking mechanism was designed against a comprehensive set of requirements and it can be classified as small-scale, central, gender mating and unpressurized. The large use of commercial components makes it low-cost and simple to be manufactured. Last, it features a good tolerance to off-nominal docking conditions and a by-design soft docking capability. The final design was extensively verified to be compliant with its requirements by means of numerical simulations and physical testing. In detail, the dynamic behaviour of the mechanism in both nominal and off-nominal conditions was assessed with the multibody dynamics analysis software MD ADAMS 2010 and functional tests were carried out within the fully integrated ARCADE experiment to ensure the docking system efficacy and to highlight possible issues. The most relevant results of the study will be presented and discussed in conclusion to this paper.

  2. Life Cycle Inventory Analysis for a Small-Scale Trawl Fishery in Sendai Bay, Japan

    Directory of Open Access Journals (Sweden)

    Kazuhito Watanabe

    2016-04-01

    Full Text Available A reduced environmental burden, while maintaining high quality and low cost, has become an important factor for achieving sustainability in the fisheries sector. The authors performed life cycle inventory (LCI analysis targeting the fish production for a small-scale trawl fishery including small trawlers operating in Sendai Bay, Japan. The average annual cumulative CO2 emissions for the small trawlers were 4.7 ton-CO2/ton-product and 8.3 ton-CO2/million Japanese yen (JPN. Total fuel consumption contributed to 97% of the global warming potential. The range of variation in the basic unit of CO2 for each small trawler was also elucidated. Energy conservation through lower fuel consumption is shown to be an effective measure for reducing CO2 in a small trawler fishery. Moreover, the authors examined the system boundary, the determination of the functional unit, and the allocation method of applying LCI analysis to fisheries. Finally, the economy and environment of small trawler fisheries are discussed as important factors for sustainable fisheries, and the life cycle approach is applied to a new fishery type in Japan.

  3. Gas explosion characterization, wave propagation (small-scale experiments)

    International Nuclear Information System (INIS)

    Larsen, G.C.

    1985-01-01

    A number of experiments have been performed with blast waves arising from the ignition of homogeneous and well defined mixtures of methane, oxygen and nitrogen, contained within spherical balloons with controlled initial dimensions. In the initial small scale experiments pressure characteristics, ground reflection phenomena and pressure distribution on box like obstacles were studied. Both configurations with one box and two closely spaced boxes have been considered, and a wave-wave interaction phenomenom was observed in the case of closely spaced obstacles. Main emphasis has been placed on the half scale field experiments. In these, the maximum flame speed has been of the order of 100 m/s, resulting in positive peak pressures of 50-100.10 2 Pa in 5 - 10 m distance from the source. The explosion process was found to be reasonable symmetric. The attenuation of the blast wave due to vegetation and the influence of obstacles as banks, walls and houses on the pressure field have been investigated. The presence of the bank and the house was felt in a zone with a length corresponding to a typical dimension of the obstacles, whereas the overall pressure field is shown to be unaffected by the type of obstacles and vegetation investigated. For the wall and house, reflection factors have been established, and some variation over the surface has been measured. The scatter of the pressure measurements is estimated for stable, neutral and unstable atmospheric conditions, and an attempt to determine the ground reflection factor has been performed. Finally the accelerations of a house exposed to the blast wave have been examined

  4. Exporting environmental products: A small business's perspective

    International Nuclear Information System (INIS)

    Marsh, K.

    1992-01-01

    If the last year and a half are any indication it would appear that the early 1990's will be to international trade what the early 1980's were to entrepreneurship. Embraced by the popular and business press and encouraged by the administration, exporting has become one of the most talked about topics in business today. As manufacturers, consultants and service providers we are continually told that to survive in the world marketplace we must think globally and compete aggressively. There can be no doubt that export markets, always an interesting sector of business, have become both more important and exciting in recent years. On January 1, 1993 the unified common market of the European Community will officially open for business. Although most of the significant changes in that market have already taken place or been agreed upon, this historic event - creating the single largest market among industrial nations - will undoubtedly have an effect on how we as exporters do business in Europe. The Free Trade Agreement with Canada has been in effect for over two years now and there have been and will continue to be many benefits for us. In developing and newly capitalist countries we can point to Czechoslovakia and Hungary as the first of several potentially lucrative markets. Mexico, in the spotlight due to the new Free Trade initiative, will be a strong new export market in our own backyard. And finally the so called mini-dragons of Southeast Asia cannot be ignored. Whether or not they choose to create a formal trading bloc, their ever increasing foreign reserves should be looked at with hungry, but cautious eyes. In this paper the author identifies a large and ever increasing world of customers beyond our national borders and identifies how those companies and individuals in the environmental products market can benefit greatly

  5. Ammonia Production In Poultry Houses And Its Effect On The Growth Of Gallus Gallus Domestica Broiler Chickens A Case Study Of A Small Scale Poultry House In Riverside Kitwe Zambia

    Directory of Open Access Journals (Sweden)

    Patrick Sipalo Maliselo

    2015-04-01

    Full Text Available Abstract Chickens deaminate excess amino acids and excrete the derived nitrogen in the urine mainly as uric acid which is readily converted to ammonia. This gas has adverse effects on the health of chickens and air quality. Production of ammonia and its effect on the growth of chickens was monitored at a poultry house of House Number 5743 Mukuba Road in Riverside Kitwe from 21st August 2013 to 6th June 2014. Two batches of fifty day old hybrid broiler chicks were bred in house A and B 5 m x 7 m under the same management system in three phases. House A chicks were fed on Novatek feed only while those in house B were fed on Novatek feed blended with 0.5 0.7 and 0.9 ww bamboo charcoal of amp8804600m particle size. Weekly mass recording by the use of a weighing scale provided a measure of growth rate while analysis of the excreta using Kjeldahl method at the Copperbelt University and Nkana Water and Sewerage Company laboratories in Kitwe provided a means of monitoring the amount of ammonia generated. Chickens in house B showed a slightly faster growth rate from 28 to 42 days than those in house A. The f-test results from the study showed that there was a significant effect of ammonia concentration on chicken growth rate P0.05. The results obtained from excreta-litter mixture analysis showed a significant adsorption of ammonia by bamboo charcoal P0.05. The study further indicated a direct dependency of ammonia concentration in excreta on chicken age moisture content and pH.

  6. Small-scale geodiversity and dirt road management, Ede (NL)

    Science.gov (United States)

    van den Ancker, Hanneke; Jungerius, Pieter Dirk

    2016-04-01

    A large part of the countryside roads on the Pleistocene sands of The Netherlands are dirt roads. Most are footpaths, but a small percentage are relatively heavily used by motorized vehicles. These latter roads are a cause subject of debate. Puddles and potholes develop during periods of wet weather, while dust whirls from the roads form during spells of dry weather as do washboard ripples. They cause problems for people living along these roads and tourists (walkers and bikers. The community of Ede (NL), like many other communities on the sand, wants to keep its 80 km of dirt roads because of the natural values they harbour as well as for their characteristic landscape quality and cultural heritage value. A part of the dirt roads in Ede is heavily used. In 2009, the community of Ede developed a decision model to support management of the dirt roads. Ede acknowledges that each dirt road is unique and asks for a tailor-made solution. Road maintenance measures include grading, making a camber, digging pits, applying loam or sandy loam. If problems become too large, one-way traffic can be an option. In more and more cases the dirt roads are barred for motorized through traffic (Gemeente Ede, 2009). As a reconnaissance we have studied the dirt roads of the Horabos/Horalaan over the last year. Incidentally we looked at other parts of the main Horalaan and the footpaths in the adjacent forest of Hoekelum. All dirt roads lie near the top of a Saalian push-moraine in which the upper course of dry valleys are present. Some results of the reconnaissance: - Most dirt roads sections in the Horabos lie lower than the surrounding terrain; - The problems develop in a short period of time during special weather conditions; - Certain dirt road sections e.g. those sections crossing a slight depression are quickly developing potholes; - Even a small slope of the road (differences that have consequences for its maintenance. Knowledge of geodiversity of the terrain and study of small-scale

  7. US bureau of mines small-scale arc melter tests

    International Nuclear Information System (INIS)

    O'Connor, W.K.; Oden, L.L.; Turner, P.C.; Davis, D.L.

    1993-01-01

    The US Bureau of Mines, in cooperation with the Idaho National Engineering Laboratory (INEL), conducted over 30 hours of melting tests to vitrify simulated low-level radioactive wastes from the INEL. Radioactive Waste Management Complex (RWMC). Five separate waste compositions were investigated, each consisting of noncontaminated soil from the RWMC and surrogate materials used to simulate the actual buried wastes. The RWMC soil and five waste compositions were melted in a 50-lb, single-phase electric arc furnace with a water-cooled shell. These tests were conducted to determine melting parameters in preparation for a large-scale melting campaign to be conducted in the Bureau's 1-metric ton (mt), water-cooled-wall, 3-phase electric arc furnace. Bulk chemical composition was determined for each of the feed materials and for the slag, metal, fume solids, and offgas furnace products, and distributions were calculated for the key elements. The material balance for the furnace operation indicates that from 63 to 84 pct of the feed reported to the slag. Cerium, used as the surrogate for the radionuclides in the wastes, demonstrated an extremely strong affinity for the slag product. Although slag temperatures as low as 1,250 C were recorded when melting the RWMC soil, temperatures in excess of 1,600 C were necessary to achieve the fluidity required for a successful slag tap

  8. Dust: Small-scale processes with global consequences

    Science.gov (United States)

    Okin, G.S.; Bullard, J.E.; Reynolds, R.L.; Ballantine, J.-A.C.; Schepanski, K.; Todd, M.C.; Belnap, J.; Baddock, M.C.; Gill, T.E.; Miller, M.E.

    2011-01-01

    Desert dust, both modern and ancient, is a critical component of the Earth system. Atmospheric dust has important effects on climate by changing the atmospheric radiation budget, while deposited dust influences biogeochemical cycles in the oceans and on land. Dust deposited on snow and ice decreases its albedo, allowing more light to be trapped at the surface, thus increasing the rate of melt and influencing energy budgets and river discharge. In the human realm, dust contributes to the transport of allergens and pathogens and when inhaled can cause or aggravate respiratory diseases. Dust storms also represent a significant hazard to road and air travel. Because it affects so many Earth processes, dust is studied from a variety of perspectives and at multiple scales, with various disciplines examining emissions for different purposes using disparate strategies. Thus, the range of objectives in studying dust, as well as experimental approaches and results, has not yet been systematically integrated. Key research questions surrounding the production and sources of dust could benefit from improved collaboration among different research communities. These questions involve the origins of dust, factors that influence dust production and emission, and methods through which dust can be monitored. ?? Author(s) 2011.

  9. Dust emission: small-scale processes with global consequences

    Science.gov (United States)

    Okin, Gregory S.; Bullard, Joanna E.; Reynolds, Richard L.; Ballantine, John-Andrew C.; Schepanski, Kerstin; Todd, Martin C.; Belnap, Jayne; Baddock, Matthew C.; Gill, Thomas E.; Miller, Mark E.

    2011-01-01

    Desert dust, both modern and ancient, is a critical component of the Earth system. Atmospheric dust has important effects on climate by changing the atmospheric radiation budget, while deposited dust influences biogeochemical cycles in the oceans and on land. Dust deposited on snow and ice decreases its albedo, allowing more light to be trapped at the surface, thus increasing the rate of melt and influencing energy budgets and river discharge. In the human realm, dust contributes to the transport of allergens and pathogens and when inhaled can cause or aggravate respiratory diseases. Dust storms also represent a significant hazard to road and air travel. Because it affects so many Earth processes, dust is studied from a variety of perspectives and at multiple scales, with various disciplines examining emissions for different purposes using disparate strategies. Thus, the range of objectives in studying dust, as well as experimental approaches and results, has not yet been systematically integrated. Key research questions surrounding the production and sources of dust could benefit from improved collaboration among different research communities. These questions involve the origins of dust, factors that influence dust production and emission, and methods through which dust can be monitored.

  10. Cell therapy-processing economics: small-scale microfactories as a stepping stone toward large-scale macrofactories.

    Science.gov (United States)

    Harrison, Richard P; Medcalf, Nicholas; Rafiq, Qasim A

    2018-03-01

    Manufacturing methods for cell-based therapies differ markedly from those established for noncellular pharmaceuticals and biologics. Attempts to 'shoehorn' these into existing frameworks have yielded poor outcomes. Some excellent clinical results have been realized, yet emergence of a 'blockbuster' cell-based therapy has so far proved elusive.  The pressure to provide these innovative therapies, even at a smaller scale, remains. In this process, economics research paper, we utilize cell expansion research data combined with operational cost modeling in a case study to demonstrate the alternative ways in which a novel mesenchymal stem cell-based therapy could be provided at small scale. This research outlines the feasibility of cell microfactories but highlighted that there is a strong pressure to automate processes and split the quality control cost-burden over larger production batches. The study explores one potential paradigm of cell-based therapy provisioning as a potential exemplar on which to base manufacturing strategy.

  11. Small-scale electric generators for arctic applications

    International Nuclear Information System (INIS)

    Lamp, T.R.

    1995-01-01

    Forest fires that have endangered remote US Air Force sites equipped with radioisotope thermoelectric generators (RTGs) has prompted the assessment of power generating systems as substitutes for RTGs in small scale (10--120 watt) applications. A team of scientists and engineers of the US Air Forces' Wright Laboratory conductd an assessment of electrical power technologies for use by the Air Force in remote, harsh environments. The surprisingly high logistics costs of operating fossil fuel generators resulted in the extension of the assessment to non-RTG sites. The candidate power sources must operate unattended for long periods at a high level of operational reliability. Selection of the optimum power generation technology is complicated and heavily driven by the severe operating environment and compounded by the remoteness of the location. It is these site-related characteristics, more than any other, that drive the selection of a safe and economical power source for Arctic applications. A number of proven power generation technologies were evaluated. The assessment concluded that RGTs are clearly the safest, most reliable, and most economical approach to supplying electrical power for remote, difficult to assess locations. The assessment also indicated that the logistics costs associated with combustion driven generator systems could be substantially reduced through the use of conversion technologies which have been previously developed for space power applications. copyright 1995 American Institute of Physics

  12. Development of a small-scale computer cluster

    Science.gov (United States)

    Wilhelm, Jay; Smith, Justin T.; Smith, James E.

    2008-04-01

    An increase in demand for computing power in academia has necessitated the need for high performance machines. Computing power of a single processor has been steadily increasing, but lags behind the demand for fast simulations. Since a single processor has hard limits to its performance, a cluster of computers can have the ability to multiply the performance of a single computer with the proper software. Cluster computing has therefore become a much sought after technology. Typical desktop computers could be used for cluster computing, but are not intended for constant full speed operation and take up more space than rack mount servers. Specialty computers that are designed to be used in clusters meet high availability and space requirements, but can be costly. A market segment exists where custom built desktop computers can be arranged in a rack mount situation, gaining the space saving of traditional rack mount computers while remaining cost effective. To explore these possibilities, an experiment was performed to develop a computing cluster using desktop components for the purpose of decreasing computation time of advanced simulations. This study indicates that small-scale cluster can be built from off-the-shelf components which multiplies the performance of a single desktop machine, while minimizing occupied space and still remaining cost effective.

  13. Small scale lithium-lead/water-interaction studies

    International Nuclear Information System (INIS)

    Kranert, O.; Kottowski, H.

    1991-01-01

    One current concept in fusion blanket design is to utilize water as the coolant and liquid lithium-lead as the breeding/neutron multiplier material. Considering the complex design of the blanket module, it is likely that a water leakage into the liquid alloy may occur due to a tube rupture provoking an intolerable pressure increase in the blanket module. The pressure increase is caused by the combined chemical and thermohydraulic reaction of lithium-lead with water. Experiments which simulate such a transient event are necessary to obtain information which is important for the blanket module design. The interaction has been investigated by conducting small-scale experiments at various injection pressures, alloy- and coolant temperatures. Besides using eutectic Li 17 Pb 83 , Li 7 Pb 2 , lithium and lead have been used. Among other results, the experiments indicate increasing chemical reaction with increasing lithium concentration. At the same time, the chemical reaction inhibits violent thermohydaulic reactions due to the attenuating effect of the hydrogen produced. The preliminary epxerimental results from Li 17 Pb 83 and Li 7 Pb 2 reveal that the pressure- and temperature transients caused by the chemical and thermohydraulic reactions lie within technically manageable limits. (orig.)

  14. Numerical simulation of a small-scale biomass boiler

    International Nuclear Information System (INIS)

    Collazo, J.; Porteiro, J.; Míguez, J.L.; Granada, E.; Gómez, M.A.

    2012-01-01

    Highlights: ► Simplified model for biomass combustion was developed. ► Porous zone conditions are used in the bed. ► Model is fully integrated in a commercial CFD code to simulate a small scale pellet boiler. ► Pollutant emissions are well predicted. ► Simulation provides extensive information about the behaviour of the boiler. - Abstract: This paper presents a computational fluid dynamic simulation of a domestic pellet boiler. Combustion of the solid fuel in the burner is an important issue when discussing the simulation of this type of system. A simplified method based on a thermal balance was developed in this work to introduce the effects provoked by pellet combustion in the boiler simulation. The model predictions were compared with the experimental measurements, and a good agreement was found. The results of the boiler analysis show that the position of the water tubes, the distribution of the air inlets and the air infiltrations are the key factors leading to the high emission levels present in this type of system.

  15. Small-scale tactile graphics for virtual reality systems

    Science.gov (United States)

    Roberts, John W.; Slattery, Oliver T.; Swope, Brett; Min, Volker; Comstock, Tracy

    2002-05-01

    As virtual reality technology moves forward, there is a need to provide the user with options for greater realism for closer engagement to the human senses. Haptic systems use force feedback to create a large-scale sensation of physical interaction in a virtual environment. Further refinement can be created by using tactile graphics to reproduce a detailed sense of touch. For example, a haptic system might create the sensation of the weight of a virtual orange that the user picks up, and the sensation of pressure on the fingers as the user squeezes the orange. A tactile graphic system could create the texture of the orange on the user's fingertips. IN the real wold, a detailed sense of touch plays a large part in picking up and manipulating small objects. Our team is working to develop technology that can drive a high density fingertip array of tactile simulators at a rapid refresh rate, sufficient to produce a realistic sense of touch. To meet the project criteria, the mechanism must be much lower cost than existing technologies, and must be sufficiently lightweight and compact to permit portable use and to enable installation of the stimulator array in the fingertip of a tactile glove. The primary intended applications for this technology are accessibility for the blind and visually impaired, teleoperation, and virtual reality systems.

  16. Resonant Wave Energy Converters: Small-scale field experiments and first full-scale prototype

    International Nuclear Information System (INIS)

    Arena, Felice; Fiamma, Vincenzo; Iannolo, Roberto; Laface, Valentina; Malara, Giovanni; Romolo, Alessandra; Strati Federica Maria

    2015-01-01

    The Resonant Wave Energy Converter 3 (REWEC3) is a device belonging to the family of Oscillating Water Columns (OWCs), that can convert the energy of incident waves into electrical energy via turbines. In contrast to classical OWCs, it incorporates a small vertical U-shaped duct to connect the water column to the open wave field. This article shows the results of a small-scale field experiment involving a REWEC3 designed for working with a 2 kW turbine. Then, the next experimental activity on a REWEC3 installed in the NOEL laboratory with the collaboration of ENEA, is presented. Finally, the first prototype of ReWEC3 under construction in Civitavecchia (Rome, Italy) is shown. The crucial features of the construction stage are discussed and some initial performances are provided. [it

  17. Agricultural Incentives: Implications for Small-Scale and Subsistence Farming in the US Caribbean Islands

    Science.gov (United States)

    Alvarez-Berrios, N.; Parés-Ramos, I.; Gould, W. A.

    2017-12-01

    The effects of climate change threaten the world's most sensitive agroecosystems and our potential to reach agricultural productivity levels needed to feed a projected global population of 9.7 billion people by 2050. The US Caribbean agriculture is especially vulnerable to the effects of climate change, due to the region's frequent exposure to extreme weather events, its geographic and economic scale, shortage of labor force, and rapid urban expansion. Currently, agriculture contributes less than 1% of the island's GDP, and over 80% of the food consumed in the region is imported. Despite low production levels, there is widespread interest in reinvigorating the agricultural sector's contribution to the economy. Local and federal institutions play a major role strengthening the agricultural sector by providing access to incentives, loans, and education for best management practices. However, many of these efforts conform to agricultural systems of larger scale of production and temperate environments. In this study, we explore agricultural incentives programs and their implication for highly diverse, small-scale, and subsistence operations that characterize agricultural systems in Puerto Rico and the US Virgin Islands. We analyze records and maps from the USDA Farm Service Agency, to typify participating farms, and to track changes in land cover, farm size, crop diversity, practices, and production levels resulting from their enrollment in such programs. Preliminary results indicate that many incentives programs are not tailored to agricultural tropical systems and prescribe alternatives that exclude traditional farming methods employed in small-scale and subsistence farms (e.g. crop insurance that benefit monoculture over intercropped systems). Moreover, many of the incentives are contradictory in their recommendations (e.g., crop insurance benefit sun-grown coffee production, while best agricultural practices recommend agroforestry with shade-grown coffee

  18. External designers in product design processes of small manufacturing firms

    NARCIS (Netherlands)

    Berends, Hans; Reymen, Isabelle; Stultiëns, Rutger G L; Peutz, Murk

    Small manufacturing firms often fail to reap the benefits of good design practices. This study investigates how the involvement of external designers influences the evolution of product design processes in small manufacturing firms. Qualitative and quantitative process research methods were used to

  19. Small-scale hydro-electric scheme in Roches, Switzerland

    International Nuclear Information System (INIS)

    Hausmann, M.

    2006-01-01

    The small hydropower plant (SHPP) project 'PCH Roches' is planned to be built in Roches, a small village located in the Jura region of the canton of Bern. The goal of this undertaking is to reactivate a site with hydro potential of the river Birs on a section that was already well exploited by some ancient SHPP (since 1953 or probably even earlier). Several modifications were performed on this plant over the years; not all contributed positively on its production figures. Following a transfer of the water rights in 1987, claims became loud against the owner to perform maintenance on the river banks and to modify the weir such that a free passage for the fishes will be granted. Those issues contributed to inflate a conflict which ended in the repeal of the water rights and a total plant shut down in 2001. The new project plans to reuse the existing pen stock and to carry out some refurbishing activities to grant security and better performance. The weir and the intake structure are also redesigned such that the water storage can be somewhat raised for normal operation; a weir gate will however allow to better discharge the river in flood situations. A new turbine house will be erected at the current location where the tail water pen stock rejoins the river. Hence, the existing old turbine house will be obsolete and the upper and lower pen stock sections are to be linked with each other. Limited by the existing pen stock size, the new plant is expected to produce some 50 kW power and 362,000 kWh/year. This represents an increase in energy generation of around 200% compared with the ancient SHPP. Gross head is 5.38 m, net head 4.12 m with a turbine flow of at least 1.6 m 3 /s. The expected energy sales price applicable to this project reaches about 0.17 CHF/kWh as per the current tariffs set by the grid owner. This project calls for the building of a state-of-the-art SHPP. It will avoid the total dismantling of the existing works to take place and allow the small

  20. Analysis of Value Chain Governance: Scenarios to Develop Small-Scale Furniture Producers

    Directory of Open Access Journals (Sweden)

    Rika Harini Irawati

    2011-05-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Furniture industry had shown a long chain of production to consumption, from raw material producers (tree growers, semi-finished producers, finished product producers, and retailers to exporters. Jepara as a centre furniture industry in Indonesia incorporates around 15,000 business units and provide livelihoods to approximately 170,000 workers. This sector contributes about 27% of Jepara‘s people domestic income. Small and medium furniture enterprises (SMEs have significant roles in the furniture industry as production structures are characterized by them. Power and information imbalance throughout the furniture value chain have resulted in problems of uneven distribution of gains among actors of the industry. SME furniture producers have experienced an unfair value added distribution. Hence, development of SMEs is important for strengthening the industry and expected to result in a portion of value added distribution to them.  We are trying to develop scenarios for SME improvement in the furniture industry in Jepara by identifying their problems and implementing Value Chain Analysis (VCA. VCA is an approach to describe SME producer relations with other actors in the industry and the governance type of their relations. Data is collected by interviewing selected SMEs from the association of small scale producers in Jepara to get detailed maps of their value chain. The research will produce future scenarios and intervention points to improve small-scale producer sustainability and better value added distribution among furniture actors. The scenarios will not only benefit selected producers but also the furniture industry of Jepara, and can be adopted for similar industries throughout Indonesia and abroad. Keywords: furniture, value chain, governance, scenario, small-scale

  1. Comparison between full- and small-scale sensory assessments of air quality

    DEFF Research Database (Denmark)

    Wargocki, Pawel; Sabikova, J.; Lagercrantz, Love Per

    2002-01-01

    Thirty-nine untrained subjects made small- and full-scale evaluations of the acceptability of the quality of air at 22 deg.C and 40% RH, polluted by either carpet, felt floor covering, painted gypsum board, linoleum or chipboard. Small-scale evaluations were made on the air extracted from 200-L......-scale sensory ratings of acceptability of air polluted by carpet and by linoleum were systematically better than small-scale assessments, but not for the other three materials. Calculated sensory emission rates from carpet and linoleum were significantly lower in full scale than in small scale. When modelling...

  2. Limited usage of mechanical equipment in small-scale rice farming: a cause for concern

    Directory of Open Access Journals (Sweden)

    Gaudiose Mujawamariya

    2017-06-01

    Full Text Available The role of mechanization in agriculture is well documented in terms of improving productivity of farm labour and land and sustaining income status and welfare of small-scale farmers. In rice production, there is a high cost associated with labour intensive production practices especially in land preparation, weeding and harvesting, the limited adoption of mechanical equipment in these operations remains an issue of concern. The current study investigates the usage of mechanical equipment in a setting where majority of farmers are exposed to technologies but cases of non-usage/adoption are observed. The choice of usage of mechanical equipment is analysed through probit and poisson models. Mechanization generally has a positive effect on production. However, the cost associated with its usage high. The equipment should be made available and affordable to farmers especially because demand for rent is not met. Awareness is essential for adoption and ease of use of mechanization.

  3. Efficiency of small scale carbon mitigation by patch iron fertilization

    Science.gov (United States)

    Sarmiento, J. L.; Slater, R. D.; Dunne, J.; Gnanadesikan, A.; Hiscock, M. R.

    2010-11-01

    While nutrient depletion scenarios have long shown that the high-latitude High Nutrient Low Chlorophyll (HNLC) regions are the most effective for sequestering atmospheric carbon dioxide, recent simulations with prognostic biogeochemical models have suggested that only a fraction of the potential drawdown can be realized. We use a global ocean biogeochemical general circulation model developed at GFDL and Princeton to examine this and related issues. We fertilize two patches in the North and Equatorial Pacific, and two additional patches in the Southern Ocean HNLC region north of the biogeochemical divide and in the Ross Sea south of the biogeochemical divide. We evaluate the simulations using observations from both artificial and natural iron fertilization experiments at nearby locations. We obtain by far the greatest response to iron fertilization at the Ross Sea site, where sea ice prevents escape of sequestered CO2 during the wintertime, and the CO2 removed from the surface ocean by the biological pump is carried into the deep ocean by the circulation. As a consequence, CO2 remains sequestered on century time-scales and the efficiency of fertilization remains almost constant no matter how frequently iron is applied as long as it is confined to the growing season. The second most efficient site is in the Southern Ocean. The North Pacific site has lower initial nutrients and thus a lower efficiency. Fertilization of the Equatorial Pacific leads to an expansion of the suboxic zone and a striking increase in denitrification that causes a sharp reduction in overall surface biological export production and CO2 uptake. The impacts on the oxygen distribution and surface biological export are less prominent at other sites, but nevertheless still a source of concern. The century time scale retention of iron in this model greatly increases the long-term biological response to iron addition as compared with simulations in which the added iron is rapidly scavenged from the

  4. The challenges of biofuels from the perspective of small-scale producers in Ohio

    International Nuclear Information System (INIS)

    Morrone, Michele; Stuart, Ben J.; McHenry, Izaak; Buckley, Geoffrey L.

    2009-01-01

    Increased interest in renewable fuels in the United States, such as biodiesel and ethanol, is mainly the result of higher cost for traditional fuels after years of low prices. A growing concern over oil imports from politically unstable parts of the world has also led people to seriously consider alternatives to gasoline. Despite this attention, there are issues that challenge the widespread acceptance of biofuels, including the availability of raw materials and food security concerns. Ohio is one of the most productive agricultural states in the country, able to contribute significant amounts of corn and soybeans, the main feedstock for biofuels. Even though Ohio is rich in the raw materials needed for biofuel production, it is still an endeavor that mainly involves small businesses that face numerous challenges. Some of these challenges are national in scope, while others are localized. Interviews with small-scale biofuels producers in Ohio identify some of the major political, economic, and perceptual hurdles confronting this fledgling industry

  5. Thermal characteristics of various biomass fuels in a small-scale biomass combustor

    International Nuclear Information System (INIS)

    Al-Shemmeri, T.T.; Yedla, R.; Wardle, D.

    2015-01-01

    Biomass combustion is a mature and reliable technology, which has been used for heating and cooking. In the UK, biomass currently qualifies for financial incentives such as the Renewable Heat Incentive (RHI). Therefore, it is vital to select the right type of fuel for a small-scale combustor to address different types of heat energy needs. In this paper, the authors attempt to investigate the performance of a small-scale biomass combustor for heating, and the impact of burning different biomass fuels on useful output energy from the combustor. The test results of moisture content, calorific value and combustion products of various biomass samples were presented. Results from this study are in general agreement with published data as far as the calorific values and moisture contents are concerned. Six commonly available biomass fuels were tested in a small-scale combustion system, and the factors that affect the performance of the system were analysed. In addition, the study has extended to examine the magnitude and proportion of useful heat, dissipated by convection and radiation while burning different biomass fuels in the small-scale combustor. It is concluded that some crucial factors have to be carefully considered before selecting biomass fuels for any particular heating application. - Highlights: • Six biomass materials combustion performance in a small combustor was examined. • Fuel combustion rate and amount of heat release has varied between materials. • Heat release by radiation, convection and flue gasses varied between materials. • Study helps engineers and users of biomass systems to select right materials

  6. Irradiation facilities for materials research: IFMIF and small scale installations

    International Nuclear Information System (INIS)

    Perlado, J. M.; Victoria, M.

    2007-01-01

    The research of advance materials in nuclear fields such as new fission reactors (Generation-IV), Accelerator Driven Systems for Transmutation of Radioactive Wastes and Nuclear Fusion, is becoming very much common in the types of low activation and radiation resistant Materials. Ferritic-Martensitic Steels (based in 9-12 Cr) with or without Oxide Dispersion Techniques (Ytria Nanoparticles), Composites materials are becoming the new generation to answer requirements of high temperature, high radiation resistance of structural materials. Special dedication is appearing in general research programmes to this area of Materials. The understanding of their final performance needs a wider knowledge of the mechanisms of radiation damage in these materials from the atomistic scale to the macroscopic responses. New extensive campaigns are being funded to irradiate from simple elements to model alloys and finally the complex materials themselves. That sequence and its state of art will be presented One clear technique for that understanding is the Multi scale Modelling which includes simulation techniques from quantum mechanics, molecular dynamics, defects diffusion, mesoscopic modelling and finally the macroscopic constitutive relations for macroscopic analysis. However, in each one of these steps is necessary a systematic and well established program of experiments that combines the irradiation and the very detailed analysis with techniques such as Transmission Electron Microscope, Positron Annihilation, SIMS, Atom Probe, Nanoindebntation. A key aspect that wants to be presented in this work is the state of art and discussion of Irradiation Facilities for Materials studies. Those facilities goes from ion implantation sources, small accelerator, Experimental Reactors such High Flux Reactor, sophisticated Triple Beams Sources as JANNUS in France to generate at the same time displacements-hydrogen-helium, and projected very large neutron installation such as IFMIF. The role to

  7. Small size modular fast reactors in large scale nuclear power

    International Nuclear Information System (INIS)

    Zrodnikov, A.V.; Toshinsky, G.I.; Komlev, O.G.; Dragunov, U.G.; Stepanov, V.S.; Klimov, N.N.; Kopytov, I.I.; Krushelnitsky, V.N.

    2005-01-01

    The report presents an innovative nuclear power technology (NPT) based on usage of modular type fast reactors (FR) (SVBR-75/100) with heavy liquid metal coolant (HLMC) i. e. eutectic lead-bismuth alloy mastered for Russian nuclear submarines' (NS) reactors. Use of this NPT makes it possible to eliminate a conflict between safety and economic requirements peculiar to the traditional reactors. Physical features of FRs, an integral design of the reactor and its small power (100 MWe), as well as natural properties of lead-bismuth coolant assured realization of the inherent safety properties. This made it possible to eliminate a lot of safety systems necessary for the reactor installations (RI) of operating NPPs and to design the modular NPP which technical and economical parameters are competitive not only with those of the NPP based on light water reactors (LWR) but with those of the steam-gas electric power plant. Multipurpose usage of transportable reactor modules SVBR-75/100 of entirely factory manufacture assures their production in large quantities that reduces their fabrication costs. The proposed NPT provides economically expedient change over to the closed nuclear fuel cycle (NFC). When the uranium-plutonium fuel is used, the breeding ratio is over one. Use of proposed NPT makes it possible to considerably increase the investment attractiveness of nuclear power (NP) with fast neutron reactors even today at low costs of natural uranium. (authors)

  8. Introduction of an energy efficiency tool for small scale biomass gasifiers – A thermodynamic approach

    International Nuclear Information System (INIS)

    Vakalis, S.; Patuzzi, F.; Baratieri, M.

    2017-01-01

    Highlights: • Analysis of plants for electricity, heat and materials production. • Thermodynamic analysis by using exergy, entransy and statistical entropy. • Extrapolation of a single efficiency index by combining the thermodynamic parameters. • Application of methodology for two monitored small scale gasifiers. - Abstract: Modern gasification plants, should be treated as poly-generation facilities because, alongside the production of electricity and heat, valuable or waste materials streams are generated. Thus, integrated methods should be introduced in order to account for the full range and the nature of the products. Application of conventional hybrid indicators that convert the output into monetary units or CO_2 equivalents are a source of bias because of the inconsistency of the conversion factors and unreliability of the available data. Therefore, this study introduces a novel thermodynamic-based method for assessing gasification plants performance by means of exergy, entransy and statistical entropy. A monitoring campaign has been implemented on two small scale gasifiers and the results have been applied on the proposed method. The energy plants are compared in respect to their individual thermodynamic parameters for energy production and materials distribution. In addition, the method returns one single value which is a resultant of all the investigated parameters and is a characteristic value of the overall performance of an energy plant.

  9. High-Temperature Structural Analysis of a Small-Scale PHE Prototype under the Test Condition of a Small-Scale Gas Loop

    International Nuclear Information System (INIS)

    Song, K.; Hong, S.; Park, H.

    2012-01-01

    A process heat exchanger (PHE) is a key component for transferring the high-temperature heat generated from a very high-temperature reactor (VHTR) to a chemical reaction for the massive production of hydrogen. The Korea Atomic Energy Research Institute has designed and assembled a small-scale nitrogen gas loop for a performance test on VHTR components and has manufactured a small-scale PHE prototype made of Hastelloy-X alloy. A performance test on the PHE prototype is underway in the gas loop, where different kinds of pipelines connecting to the PHE prototype are tested for reducing the thermal stress under the expansion of the PHE prototype. In this study, to evaluate the high-temperature structural integrity of the PHE prototype under the test condition of the gas loop, a realistic and effective boundary condition imposing the stiffness of the pipelines connected to the PHE prototype was suggested. An equivalent spring stiffness to reduce the thermal stress under the expansion of the PHE prototype was computed from the bending deformation and expansion of the pipelines connected to the PHE. A structural analysis on the PHE prototype was also carried out by imposing the suggested boundary condition. As a result of the analysis, the structural integrity of the PHE prototype seems to be maintained under the test condition of the gas loop.

  10. Position Paper on Jatropha curcas. State of the Art Small and Large Scale Project Development

    Energy Technology Data Exchange (ETDEWEB)

    Daey Ouwens, K.; Franken, Y.J.; Rijssenbeek, W. [Fuels from Agriculture in Communal Technology FACT, Eindhoven (Netherlands); Francis, G. [University of Hohenheim, Hohenheim (Germany); Riedacker, A. [French National Institute for Agricultural Research INRA, Paris (France); Foidl, N.; Jongschaap, R.; Bindraban, P. [Plant Research International PRI, Wageningen (Netherlands)

    2007-06-15

    Much information has been collected during the Seminar on Jatropha held in Wageningen, Netherlands, March 2007, summarized in this paper. Much research is still necessary to improve yield, to allow use of biological products such as oil cake as animal fodder, etc. Good documented yield data are still scarce. Cooperation with research institutions is therefore recommended. At this stage it is still particularly important to distinguish between reality, promises and dangerous extrapolations. To avoid, spectacular and regretful failures and waste of money for investors as well as great disappointments of local populations, promoters of large scale plantation are invited to adopt stepwise approaches: large scale plantations should only be considered after some 4 to 5 years obtaining experimental data (annual seed yield and oil yield, economical viability etc.) from a sufficient number of small scale experimental plots (about 1 ha) corresponding to the whole range of soil and climatic conditions of such projects.

  11. Scale Effects Related to Small Physical Modelling of Overtopping of Rubble Mound Breakwaters

    DEFF Research Database (Denmark)

    Burcharth, Hans F.; Andersen, Thomas Lykke

    2009-01-01

    By comparison of overtopping discharges recorded in prototype and small scale physical models it was demonstrated in the EU-CLASH project that small scale tests significantly underestimate smaller discharges. Deviations in overtopping are due to model and scale effects. These effects are discusse...... armour on the upper part of the slope. This effect is believed to be the main reason for the found deviations between overtopping in prototype and small scale tests....

  12. Small-scale electrical resistivity tomography of wet fractured rocks.

    Science.gov (United States)

    LaBrecque, Douglas J; Sharpe, Roger; Wood, Thomas; Heath, Gail

    2004-01-01

    This paper describes a series of experiments that tested the ability of the electrical resistivity tomography (ERT) method to locate correctly wet and dry fractures in a meso-scale model. The goal was to develop a method of monitoring the flow of water through a fractured rock matrix. The model was a four by six array of limestone blocks equipped with 28 stainless steel electrodes. Dry fractures were created by placing pieces of vinyl between one or more blocks. Wet fractures were created by injecting tap water into a joint between blocks. In electrical terms, the dry fractures are resistive and the wet fractures are conductive. The quantities measured by the ERT system are current and voltage around the outside edge of the model. The raw ERT data were translated to resistivity values inside the model using a three-dimensional Occam's inversion routine. This routine was one of the key components of ERT being tested. The model presented several challenges. First, the resistivity of both the blocks and the joints was highly variable. Second, the resistive targets introduced extreme changes the software could not precisely quantify. Third, the abrupt changes inherent in a fracture system were contrary to the smoothly varying changes expected by the Occam's inversion routine. Fourth, the response of the conductive fractures was small compared to the background variability. In general, ERT was able to locate correctly resistive fractures. Problems occurred, however, when the resistive fracture was near the edges of the model or when multiple fractures were close together. In particular, ERT tended to position the fracture closer to the model center than its true location. Conductive fractures yielded much smaller responses than the resistive case. A difference-inversion method was able to correctly locate these targets.

  13. Scaling-up vaccine production: implementation aspects of a biomass growth observer and controller

    NARCIS (Netherlands)

    Soons, Z.I.T.A.; IJssel, van den J.; Pol, van der L.A.; Straten, van G.; Boxtel, van A.J.B.

    2009-01-01

    Abstract This study considers two aspects of the implementation of a biomass growth observer and specific growth rate controller in scale-up from small- to pilot-scale bioreactors towards a feasible bulk production process for whole-cell vaccine against whooping cough. The first is the calculation

  14. Efficiency of small scale carbon mitigation by patch iron fertilization

    Directory of Open Access Journals (Sweden)

    J. L. Sarmiento

    2010-11-01

    Full Text Available While nutrient depletion scenarios have long shown that the high-latitude High Nutrient Low Chlorophyll (HNLC regions are the most effective for sequestering atmospheric carbon dioxide, recent simulations with prognostic biogeochemical models have suggested that only a fraction of the potential drawdown can be realized. We use a global ocean biogeochemical general circulation model developed at GFDL and Princeton to examine this and related issues. We fertilize two patches in the North and Equatorial Pacific, and two additional patches in the Southern Ocean HNLC region north of the biogeochemical divide and in the Ross Sea south of the biogeochemical divide. We evaluate the simulations using observations from both artificial and natural iron fertilization experiments at nearby locations. We obtain by far the greatest response to iron fertilization at the Ross Sea site, where sea ice prevents escape of sequestered CO2 during the wintertime, and the CO2 removed from the surface ocean by the biological pump is carried into the deep ocean by the circulation. As a consequence, CO2 remains sequestered on century time-scales and the efficiency of fertilization remains almost constant no matter how frequently iron is applied as long as it is confined to the growing season. The second most efficient site is in the Southern Ocean. The North Pacific site has lower initial nutrients and thus a lower efficiency. Fertilization of the Equatorial Pacific leads to an expansion of the suboxic zone and a striking increase in denitrification that causes a sharp reduction in overall surface biological export production and CO2 uptake. The impacts on the oxygen distribution and surface biological export are less prominent at other sites, but nevertheless still a source of concern. The century time scale retention of iron in this model greatly increases the long-term biological response to iron addition as compared with

  15. Genetically modified crops and small-scale farmers: main opportunities and challenges.

    Science.gov (United States)

    Azadi, Hossein; Samiee, Atry; Mahmoudi, Hossein; Jouzi, Zeynab; Khachak, Parisa Rafiaani; De Maeyer, Philippe; Witlox, Frank

    2016-01-01

    Although some important features of genetically modified (GM) crops such as insect resistance, herbicide tolerance, and drought tolerance might seem to be beneficial for small-scale farmers, the adoption of GM technology by smallholders is still slight. Identifying pros and cons of using this technology is important to understand the impacts of GM crops on these farmers. This article reviews the main opportunities and challenges of GM crops for small-scale farmers in developing countries. The most significant advantages of GM crops include being independent to farm size, environment protection, improvement of occupational health issues, and the potential of bio-fortified crops to reduce malnutrition. Challenges faced by small-scale farmers for adoption of GM crops comprise availability and accessibility of GM crop seeds, seed dissemination and price, and the lack of adequate information. In addition, R&D and production costs in using GM crops make it difficult for these farmers to adopt the use of these crops. Moreover, intellectual property right regulations may deprive resource poor farmers from the advantages of GM technology. Finally, concerns on socio-economic and environment safety issues are also addressed in this paper.

  16. Grounding the nexus: Examining the integration of small-scale irrigators into a national food security programme in Burkina Faso

    Directory of Open Access Journals (Sweden)

    Brian Dowd-Uribe

    2018-06-01

    Full Text Available The water-food nexus literature examines the synergies and trade-offs of resource use but is dominated by large-scale analyses that do not sufficiently engage the local dimensions of resource management. The research presented here addresses this gap with a local-scale analysis of integrated water and food management in Burkina Faso. Specifically, we analyse the implementation of a national food security campaign (Opération Bondofa to boost maize production in a subbasin that exhibits two important trends in Africa: a large increase in small-scale irrigators and the decentralisation of water management. As surface water levels dropped in the region, entities at different scales asserted increased control over water allocation, exposing the contested nature of new decentralised institutions, and powerful actors’ preference for local control. These scalar power struggles intersected with a lack of knowledge of small-scale irrigators’ cultural practices to produce an implementation and water allocation schedule that did match small-scale irrigator needs, resulting in low initial enthusiasm for the project. Increased attention from national governments to strengthen decentralised water management committees and spur greater knowledge of, and engagement with, small-scale irrigators can result in improved programme design to better incorporate small-scale irrigators into national food security campaigns.

  17. Handbook for Small-Scale Densified Biomass Fuel (Pellets) Manufacturing for Local Markets.

    Energy Technology Data Exchange (ETDEWEB)

    Folk, Richard L.; Govett, Robert L.

    1992-07-01

    Wood pellet manufacturing in the Intermountain West is a recently founded and rapidly expanding energy industry for small-scale producers. Within a three-year period, the total number of manufacturers in the region has increased from seven to twelve (Folk et al., 1988). Small-scale industry development is evolving because a supply of raw materials from small and some medium-sized primary and secondary wood processors that has been largely unused. For the residue producer considering pellet fuel manufacturing, the wastewood generated from primary products often carries a cost associated with residue disposal when methods at-e stockpiling, landfilling or incinerating. Regional processors use these methods for a variety of reasons, including the relatively small amounts of residue produced, residue form, mixed residue types, high transportation costs and lack of a local market, convenience and absence of regulation. Direct costs associated with residue disposal include the expenses required to own and operate residue handling equipment, costs for operating and maintaining a combustor and tipping fees charged to accept wood waste at public landfills. Economic and social costs related to environmental concerns may also be incurred to include local air and water quality degradation from open-air combustion and leachate movement into streams and drinking water.

  18. Increased power to heat ratio of small scale CHP plants using biomass fuels and natural gas

    International Nuclear Information System (INIS)

    Savola, Tuula; Fogelholm, Carl-Johan

    2006-01-01

    In this paper, we present a systematic study of process changes for increased power production in 1-20 MW e combined heat and power (CHP) plants. The changes are simulated, and their economic feasibility evaluated by using existing small scale CHP case plants. Increasing power production in decentralised CHP plants that operate according to a certain heat demand could reduce the fuel consumption and CO 2 emissions per power unit produced and improve the feasibility of CHP plant investments. The CHP plant process changes were simulated under design and off design conditions and an analysis of power and heat production, investment costs and CO 2 emissions was performed over the whole annual heat demand. The results show that using biomass fuels, there are profitable possibilities to increase the current power to heat ratios, 0.23-0.48, of the small scale CHP plants up to 0.26-0.56, depending on the size of the plant. The profitable changes were a two stage district heat exchanger and the addition of a steam reheater and a feed water preheater. If natural gas is used as an additional fuel, the power to heat ratio may be increased up to 0.35-0.65 by integrating a gas engine into the process. If the CO 2 savings from the changes are also taken into account, the economic feasibility of the changes increases. The results of this work offer useful performance simulation and investment cost knowledge for the development of more efficient and economically feasible small scale CHP processes

  19. Impact of value chain governance on the development of small scale shrimp farmers in Vietnam

    Directory of Open Access Journals (Sweden)

    T. M. H. Ho

    2016-06-01

    Full Text Available Purpose of this paper is to identify the tendency of shrimp value chain development and impact of its governance on the small scale shrimp farmers in Vietnam. Design/methodology/approach - Data from the shrimp farmers surveys in Mekong delta, Vietnam from 2008-2010 with the update information in 2014 were taken to analyse by the value chain analysis method. Findings – Traditional governance type of the shrimp value chain in the early state (before 2004 showed the different levels of coordination of farmers with collectors, among collectors, and collectors with processing plants. In this type of governance, trust and linkages are inextricably linked. However, they are not strong. The processing plants determine shrimp prices and quality requirement in the market while many collectors do not seem to be highly responsible for the quality of their products. To avoid this limitation, with the governmental support policy to improve farmers’ income, the processing plants set up a direct buying from farmers under contracts. These contracts led to a new governance type with an expectation of improving farmers' position. However, this model was broken due to several reasons including un-controlled shrimp raw material from small scale and individual farmers. Consequently, processors now tend to establish their own raw material zone to comply shrimp quality assurance, and eject the existence of farmers. This will lead small scale farmers to very difficult problems in finding the market. Poverty and social problems of small scale farmers might appear. The result recommends a greater strengthening and tightening of the value chain. Re-organizing shrimp farmers into legal teams or groups that help farmers to re-participate in the game with others actor in the chain is crucial. Research limitations/implications - The research mainly follows inductive approach in w

  20. Implementation Of 5S Methodology In The Small Scale Industry A Case Study

    Directory of Open Access Journals (Sweden)

    R. S. Agrahari

    2015-04-01

    Full Text Available Abstract 5S is a basic foundation of Lean Manufacturing systems. It is a tool for cleaning sorting organizing and providing the necessary groundwork for workpiece improvement. This paper dealt with the implementation of 5S methodology in the small scale industry. By following the 5S methodology it shows significant improvements to safety productivity efficiency and housekeeping. The improvements before and after 5S implementation is shown by pictures in the paper. It also intends to build a stronger work ethic within the management and workers who would be expected to continue the good practices.

  1. Basic study natural gas small-scale consumption 1991 in the Netherlands

    International Nuclear Information System (INIS)

    Weegink, R.J.; Abbing, H.W.

    1991-01-01

    The consumption of natural gas by Dutch households and underlying trends influencing the natural gas consumption are investigated annually by means of a survey involving more than 2,700 households. The small-scale consumption totals some 11,65 billion m 3 in 1991 of which 79% was used for space heating and 18% for hot water production. Data are presented on types of residential buildings, the penetration of several forms of thermal insulation, the penetration of cooking appliances, heating systems, and fireplaces per building type, and natural gas consumption for space heating, also per type of building. 7 figs., 14 tabs

  2. Occurrence of Eimeria species parasites on small-scale commercial chicken farms in Africa and indication of economic profitability.

    Directory of Open Access Journals (Sweden)

    Kimberly M Fornace

    Full Text Available Small-scale commercial poultry production is emerging as an important form of livestock production in Africa, providing sources of income and animal protein to many poor households, yet the occurrence and impact of coccidiosis on this relatively new production system remains unknown. The primary objective of this study was to examine Eimeria parasite occurrence on small-scale commercial poultry farms in Ghana, Tanzania and Zambia. Additionally, farm economic viability was measured by calculating the farm gross margin and enterprise budget. Using these economic measures as global assessments of farm productivity, encompassing the diversity present in regional husbandry systems with a measure of fundamental local relevance, we investigated the detection of specific Eimeria species as indicators of farm profitability. Faecal samples and data on production parameters were collected from small-scale (less than 2,000 birds per batch intensive broiler and layer farms in peri-urban Ghana, Tanzania and Zambia. All seven Eimeria species recognised to infect the chicken were detected in each country. Furthermore, two of the three genetic variants (operational taxonomic units identified previously in Australia have been described outside of Australia for the first time. Detection of the most pathogenic Eimeria species associated with decreased farm profitability and may be considered as an indicator of likely farm performance. While a causal link remains to be demonstrated, the presence of highly pathogenic enteric parasites may pose a threat to profitable, sustainable small-scale poultry enterprises in Africa.

  3. Occurrence of Eimeria Species Parasites on Small-Scale Commercial Chicken Farms in Africa and Indication of Economic Profitability

    Science.gov (United States)

    Fornace, Kimberly M.; Clark, Emily L.; Macdonald, Sarah E.; Namangala, Boniface; Karimuribo, Esron; Awuni, Joseph A.; Thieme, Olaf; Blake, Damer P.; Rushton, Jonathan

    2013-01-01

    Small-scale commercial poultry production is emerging as an important form of livestock production in Africa, providing sources of income and animal protein to many poor households, yet the occurrence and impact of coccidiosis on this relatively new production system remains unknown. The primary objective of this study was to examine Eimeria parasite occurrence on small-scale commercial poultry farms in Ghana, Tanzania and Zambia. Additionally, farm economic viability was measured by calculating the farm gross margin and enterprise budget. Using these economic measures as global assessments of farm productivity, encompassing the diversity present in regional husbandry systems with a measure of fundamental local relevance, we investigated the detection of specific Eimeria species as indicators of farm profitability. Faecal samples and data on production parameters were collected from small-scale (less than 2,000 birds per batch) intensive broiler and layer farms in peri-urban Ghana, Tanzania and Zambia. All seven Eimeria species recognised to infect the chicken were detected in each country. Furthermore, two of the three genetic variants (operational taxonomic units) identified previously in Australia have been described outside of Australia for the first time. Detection of the most pathogenic Eimeria species associated with decreased farm profitability and may be considered as an indicator of likely farm performance. While a causal link remains to be demonstrated, the presence of highly pathogenic enteric parasites may pose a threat to profitable, sustainable small-scale poultry enterprises in Africa. PMID:24391923

  4. Occurrence of Eimeria species parasites on small-scale commercial chicken farms in Africa and indication of economic profitability.

    Science.gov (United States)

    Fornace, Kimberly M; Clark, Emily L; Macdonald, Sarah E; Namangala, Boniface; Karimuribo, Esron; Awuni, Joseph A; Thieme, Olaf; Blake, Damer P; Rushton, Jonathan

    2013-01-01

    Small-scale commercial poultry production is emerging as an important form of livestock production in Africa, providing sources of income and animal protein to many poor households, yet the occurrence and impact of coccidiosis on this relatively new production system remains unknown. The primary objective of this study was to examine Eimeria parasite occurrence on small-scale commercial poultry farms in Ghana, Tanzania and Zambia. Additionally, farm economic viability was measured by calculating the farm gross margin and enterprise budget. Using these economic measures as global assessments of farm productivity, encompassing the diversity present in regional husbandry systems with a measure of fundamental local relevance, we investigated the detection of specific Eimeria species as indicators of farm profitability. Faecal samples and data on production parameters were collected from small-scale (less than 2,000 birds per batch) intensive broiler and layer farms in peri-urban Ghana, Tanzania and Zambia. All seven Eimeria species recognised to infect the chicken were detected in each country. Furthermore, two of the three genetic variants (operational taxonomic units) identified previously in Australia have been described outside of Australia for the first time. Detection of the most pathogenic Eimeria species associated with decreased farm profitability and may be considered as an indicator of likely farm performance. While a causal link remains to be demonstrated, the presence of highly pathogenic enteric parasites may pose a threat to profitable, sustainable small-scale poultry enterprises in Africa.

  5. A New Strategy for Utilizing Rice Forage Production Using a No-Tillage System to Enhance the Self-Sufficient Feed Ratio of Small Scale Dairy Farming in Japan

    Directory of Open Access Journals (Sweden)

    Windi Al Zahra

    2014-08-01

    Full Text Available Rice forage systems can increase the land use efficiency in paddy fields, improve the self-sufficient feed ratio, and provide environmental benefits for agro-ecosystems. This system often decreased economic benefits compared with those through imported commercial forage feed, particularly in Japan. We observed the productivities of winter forage after rice harvest between conventional tillage (CT and no-tillage (NT in a field experiment. An on-farm evaluation was performed to determine the self-sufficient ratio of feed and forage production costs based on farm evaluation of the dairy farmer and the rice grower, who adopted a rice forage system. The field experiment detected no significant difference in forage production and quality between CT and NT after rice harvest. However, the production cost was dramatically decreased by 28.1% in NT compared with CT. The self-sufficient ratio was 5.4% higher when dairy farmers adopted the rice forage system compared with those using the current management system. Therefore, this study demonstrated the positive benefits for dairy farmers and rice growers in Japan when adopting a rice forage system with NT, which could improve the self-sufficient feed ratio and reduce production costs.

  6. Small scale plasticity and compressive properties of composites

    DEFF Research Database (Denmark)

    Mikkelsen, Lars Pilgaard

    in the commercial finite element code Abaqus [3]. In addition, in a supplementary study, taken into account the length scale effect of the yielding behavior using a strain gradient dependent plasticity law [4] implemented as a user element [5], it is possible investigating the scale effect on the yielding behavior...

  7. Production of charcoal from woods and bamboo in a small natural draft carbonizer

    Energy Technology Data Exchange (ETDEWEB)

    Tippayawong, Nakorn; Saengow, Nakarin; Chaiya, Ekarin

    2010-07-01

    There is a strong domestic market for charcoal in Thailand and many developing countries. Charcoal is usually made from biomass materials in small scale, simple kilns. Traditional charcoal making kilns adopts a process that is very inefficient, and damaging to the environment. In this work, an alternative charcoal reactor based on natural draft, pyrolysis gas burning concept was proposed and demonstrated. Tests with longan woods and bamboo showed that good quality charcoal can be produced in shorter time with lower pollution emissions, compared with traditional kilns. The proposed carbonizer proved to be suitable for small scale, charcoal production in rural area.

  8. QCD results for small x and for heavy flavor production

    International Nuclear Information System (INIS)

    Collins, J.C.

    1985-01-01

    Two areas of perturbative quantum chromodynamics are reviewed. The first is hard collisions of partons whose momentum is a small fraction, named x, of the total center-of-mass energy of the momenta of their parent hadrons. The second is production of heavy strongly-interacting particles, such as ordinary heavy quarks, squarks, or gluinos. The discussion of the small x problem includes Monte Carlo calculations of multiple scattering and theoretical calculations of parton-parton shadowing effects. As for heavy flavor production, it is shown that ordinary perturbative methods should apply. 22 refs., 7 figs

  9. Mercury Pollution Due to Small-Scale Gold Mining in the Philippines: An Economic Analysis

    OpenAIRE

    Orbeta, Aniceto C.; Israel, Danilo C.; Asirot, Jasminda

    2000-01-01

    The study reviews small-scale gold mining in the Philippines and economically assesses mercury pollution and other development problems in the industry. The end purpose is to suggest measures to address the problems and promote better environmental and overall management of small-scale mining. The study has used secondary data from mining institutions and primary data from key informants and small-scale gold miners and processors in the two case study sites.

  10. Mercury Pollution Due to Small-Scale Gold Mining in the Philippines: An Economic Analysis

    OpenAIRE

    Israel, Danilo C.; Asirot, Jasminda

    2002-01-01

    The study reviews small-scale gold mining in the Philippines and economically assesses mercury pollution and other development problems in the industry. The end purpose is to suggest measures to address the problems and promote better environmental and overall management of small-scale mining. The study has used secondary data from mining institutions and primary data from key informants and small-scale gold miners and processors in the two case study sites. brazzer

  11. Process assessment of small scale low temperature methanol synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Hendriyana [Chemical Engineering Department, Faculty of Engineering, Jenderal Achmad Yani Univerity (Indonesia); Chemical Engineering Department, Faculty of Industrial Technology, InstitutTeknologi Bandung (Indonesia); Susanto, Herri, E-mail: herri@che.itb.ac.id; Subagjo [Chemical Engineering Department, Faculty of Industrial Technology, InstitutTeknologi Bandung (Indonesia)

    2015-12-29

    Biomass is a renewable energy resource and has the potential to make a significant impact on domestic fuel supplies. Biomass can be converted to fuel like methanol via several step process. The process can be split into following main steps: biomass preparation, gasification, gas cooling and cleaning, gas shift and methanol synthesis. Untill now these configuration still has a problem like high production cost, catalyst deactivation, economy of scale and a huge energy requirements. These problems become the leading inhibition for biomass conversion to methanol, which should be resolved to move towards the economical. To address these issues, we developed various process and new configurations for methanol synthesis via methyl formate. This configuration combining two reactors: the one reactor for the carbonylation of methanol and CO to form methyl formate, and the second for the hydrogenolysis of methyl formate and H{sub 2} to form two molecule of methanol. Four plant process configurations were compared with the biomass basis is 300 ton/day. The first configuration (A) is equipped with a steam reforming process for converting methane to CO and H{sub 2} for increasing H{sub 2}/CO ratio. CO{sub 2} removal is necessary to avoid poisoning the catalyst. COSORB process used for the purpose of increasing the partial pressure of CO in the feed gas. The steam reforming process in B configuration is not used with the aim of reducing the number of process equipment, so expect lower investment costs. For C configuration, the steam reforming process and COSORB are not used with the aim of reducing the number of process equipment, so expect lower investment costs. D configuration is almost similar to the configuration A. This configuration difference is in the synthesis of methanol which was held in a single reactor. Carbonylation and hydrogenolysis reactions carried out in the same reactor one. These processes were analyzed in term of technical process, material and energy

  12. Process assessment of small scale low temperature methanol synthesis

    International Nuclear Information System (INIS)

    Hendriyana; Susanto, Herri; Subagjo

    2015-01-01

    Biomass is a renewable energy resource and has the potential to make a significant impact on domestic fuel supplies. Biomass can be converted to fuel like methanol via several step process. The process can be split into following main steps: biomass preparation, gasification, gas cooling and cleaning, gas shift and methanol synthesis. Untill now these configuration still has a problem like high production cost, catalyst deactivation, economy of scale and a huge energy requirements. These problems become the leading inhibition for biomass conversion to methanol, which should be resolved to move towards the economical. To address these issues, we developed various process and new configurations for methanol synthesis via methyl formate. This configuration combining two reactors: the one reactor for the carbonylation of methanol and CO to form methyl formate, and the second for the hydrogenolysis of methyl formate and H 2 to form two molecule of methanol. Four plant process configurations were compared with the biomass basis is 300 ton/day. The first configuration (A) is equipped with a steam reforming process for converting methane to CO and H 2 for increasing H 2 /CO ratio. CO 2 removal is necessary to avoid poisoning the catalyst. COSORB process used for the purpose of increasing the partial pressure of CO in the feed gas. The steam reforming process in B configuration is not used with the aim of reducing the number of process equipment, so expect lower investment costs. For C configuration, the steam reforming process and COSORB are not used with the aim of reducing the number of process equipment, so expect lower investment costs. D configuration is almost similar to the configuration A. This configuration difference is in the synthesis of methanol which was held in a single reactor. Carbonylation and hydrogenolysis reactions carried out in the same reactor one. These processes were analyzed in term of technical process, material and energy balance and economic

  13. Small-scale Aquaculture to Strengthen Food Security in Cambodia ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    , vitamin A, protein, and essential fatty acids. Six hundred (600) households largely headed by women farmers are raising small nutrient-rich fish for their families' consumption in the same ponds as large fish, which can be sold for income.

  14. prospects and challenges of artisanal and small-scale mining

    African Journals Online (AJOL)

    RAYAN_

    among its African peers as an expert in the mining industry. The mining ..... different aspects of the mining value chain and supporting activities. The committee also .... creating a conducive environment for the development and growth of small.

  15. Efficiency of resource use in small-scale white shrimp (Penaeus vannamei production in Lamongan Regency, East Java Province, Indonesia Wydajność wykorzystania zasobów w produkcji białej krewetki (Penaeus vannamei na małą skalę w regencji Lamongan, prowincji Wschodnia Jawa w Indonezji

    Directory of Open Access Journals (Sweden)

    Riski A. Lestariadi

    2012-12-01

    Full Text Available This study carried out to determine the efficiency of recourses used in white shrimp (Pe-naeus Vannamei production in Lamongan Regency, East Java Province, Indonesia. The simple random sampling technique used to select 125 small-scale white shrimp farmers from six-study areas in Lamongan Regency. The white shrimp production function was es-timated using Ordinary Least Square (OLS technique. The results indicated that Double Log production function had the best fit in explaining the relationship between output of white shrimp and inputs used. The coefficient of determination (R2 = 0.846 indicated that the eighty-four point six percent of variation in output of white shrimp was explained by the independent variables in the model. Findings showed that labor, fertilizer, feed and stocking density are significant determinants of production inputs. Moreover, the estimates of the ra-tio of the value of marginal product (VMP to marginal factor cost (MFC revealed that the non-optimal combination of inputs among the white shrimp farmers, it showed that the aq-uaculture farms resources were inefficiently utilized for labor, feed and stocking density by 1.94, 1.93 and 171.4 respectively, while fertilizer showed otherwise by 0.11 or over uti-lized.

  16. Efficiency Comparison between Conventional and Modern Port Operation System for Small-Scale Dry Bulk Cargo

    Directory of Open Access Journals (Sweden)

    Tiara Aulia

    2018-01-01

    Full Text Available Since the launching of Sea Toll Road Program in 2015, the improvement in ports’ operation systems has become Indonesia’s foremost necessity. This improvement commonly leads to equipment modernization, while realistically, modern equipment does not always amount to a productive performance, especially in the context of small-scale ports. Instead, it is prone to creating wasteful capital and maintenance cost as well as making the planning time ineffective. This study compares two options of port operation systems in a small port, which is conventional and technologically-advanced method for dry bulk cargo. It results in thin gaps between each option’s financial assessment variables, which are Internal Rate of Return, Benefit/Cost Ratio and Payback Period, regardless of a stark difference between each option’s equipment cost. This study concludes that with the right approach, the conventional operation system is still the most efficient option compared to its contemporary opposite.

  17. On the suitability of roach, perch, vendace and whitefish for canning in small scale canning stations

    Directory of Open Access Journals (Sweden)

    Mailis Kuuppo

    1978-07-01

    Full Text Available The suitability of roach (Rutilus rutilus, perch (Perca fluviatilis, vendace (Coregonus albula L., and whitefish (Coregonus sp. for canning in small scale canning stations was tested. Various pretreatment methods and processing conditions were evaluated for different fish species. Processing equipment suitable for small scale canning stations was developed in the course of this study. The keepability of the canned products was followed by physical, organoleptic and microbiological determinations during a period of 18 months. The roach, vendace and whitefish preserves were of the types »canned fish in tomato sauce» and »canned fish in oil and its own juice» and the perch preserves of the type »canned fish in brine». Roach, vendace and whitefish were salted by immersing into 21 % brine for 4—25 minutes depending on the size of the fish and preheated by smoking at 90° C for 60 —120 minutes. Products of good quality were obtained from whitefish which was dried by cooking in oil at 120 °C for 3 minutes instead of smoking. The perch were cooked in 3 % and 4 % brine for 15—20 minutes depending on the size of the fish. The best time and temperature combination for the aimed F value 10 and for a product of good quality was 60 minutes at 115°C when using rotation. In organoleptic evaluation all the canned products were judged to be of good quality and there were no significant changes in appearance, texture, taste or aroma during 18 months' storage at room temperature. No microbial growth or swelling of the cans was detected during storage. Use of frozen raw material in canning whitefish had no detectable effect on the quality of the final product.

  18. Upgrading Wood-Based Industries: Harnessing the Social Network of Small-Scale Furniture Producers and Their Institutions

    Directory of Open Access Journals (Sweden)

    Melati ,

    2011-05-01

    Full Text Available Furniture is a major export commodity in Indonesia with a total value of USD 1.96 million in 2007.  Jepara District is one of the key location for wood furniture production with 15,271 furniture related business units employing 176,469 workers.  However, inefficiencies and power imbalances throughout the furniture value chain have resulted in overharvesting and uneven distribution of gains among the industry’s actors.  In contrast to price-setting international furniture retailers, small-scale producers enjoy the least value from their products.  In order to increase added value and competitiveness, small-scale furniture producers have made efforts to upgrade by harnessing their social network and institutions.  This paper describes small-scale furniture producers’ efforts to upgrade by utilising their social network and institutions in Jepara.  Data was collected through in-depth interviews with members of the small-scale furniture producers’ association.  The research provides insight into the nature of social networks and information flow and develops future scenarios to upgrade.  The scenarios will not only benefit the furniture industry in Jepara, but may also be adopted for similar industries throughout Indonesia and the world, and potentially improve many people’s economies and livelihoods.Keywords: wood-based industry, furniture, small-scale, social network, institution

  19. Pervious concrete fill in Pearl-Chain Bridges: Using small-scale results in full-scale implementation

    DEFF Research Database (Denmark)

    Lund, Mia Schou Møller; Hansen, Kurt Kielsgaard; Truelsen, R.

    2016-01-01

    distribution and strength properties is determined for 800 mm high blocks cast in different numbers of layers, and (2) full-scale implementation in a 26 m long Pearl-Chain Bridge. With a layer thickness of 27 cm, the small-scale tests indicated homogenous results; however, for the full-scale implementation......Pearl-Chain Bridge technology is a new prefabricated arch solution for highway bridges. This study investigates the feasibility of pervious concrete as a filling material in Pearl-Chain Bridges. The study is divided into two steps: (1) small-scale tests where the variation in vertical void...

  20. Accounting for small scale heterogeneity in ecohydrologic watershed models

    Science.gov (United States)

    Burke, W.; Tague, C.

    2017-12-01

    Spatially distributed ecohydrologic models are inherently constrained by the spatial resolution of their smallest units, below which land and processes are assumed to be homogenous. At coarse scales, heterogeneity is often accounted for by computing store and fluxes of interest over a distribution of land cover types (or other sources of heterogeneity) within spatially explicit modeling units. However this approach ignores spatial organization and the lateral transfer of water and materials downslope. The challenge is to account both for the role of flow network topology and fine-scale heterogeneity. We present a new approach that defines two levels of spatial aggregation and that integrates spatially explicit network approach with a flexible representation of finer-scale aspatial heterogeneity. Critically, this solution does not simply increase the resolution of the smallest spatial unit, and so by comparison, results in improved computational efficiency. The approach is demonstrated by adapting Regional Hydro-Ecologic Simulation System (RHESSys), an ecohydrologic model widely used to simulate climate, land use, and land management impacts. We illustrate the utility of our approach by showing how the model can be used to better characterize forest thinning impacts on ecohydrology. Forest thinning is typically done at the scale of individual trees, and yet management responses of interest include impacts on watershed scale hydrology and on downslope riparian vegetation. Our approach allow us to characterize the variability in tree size/carbon reduction and water transfers between neighboring trees while still capturing hillslope to watershed scale effects, Our illustrative example demonstrates that accounting for these fine scale effects can substantially alter model estimates, in some cases shifting the impacts of thinning on downslope water availability from increases to decreases. We conclude by describing other use cases that may benefit from this approach

  1. Optimization Study of Small-Scale Solar Membrane Distillation Desalination Systems (s-SMDDS

    Directory of Open Access Journals (Sweden)

    Hsuan Chang

    2014-11-01

    Full Text Available Membrane distillation (MD, which can utilize low-grade thermal energy, has been extensively studied for desalination. By incorporating solar thermal energy, the solar membrane distillation desalination system (SMDDS is a potential technology for resolving energy and water resource problems. Small-scale SMDDS (s-SMDDS is an attractive and viable option for the production of fresh water for small communities in remote arid areas. The minimum cost design and operation of s-SMDDS are determined by a systematic method, which involves a pseudo-steady-state approach for equipment sizing and dynamic optimization using overall system mathematical models. Two s-SMDDS employing an air gap membrane distillation module with membrane areas of 11.5 m2 and 23 m2 are analyzed. The lowest water production costs are $5.92/m3 and $5.16/m3 for water production rates of 500 kg/day and 1000 kg/day, respectively. For these two optimal cases, the performance ratios are 0.85 and 0.91; the recovery ratios are 4.07% and 4.57%. The effect of membrane characteristics on the production cost is investigated. For the commercial membrane employed in this study, the increase of the membrane mass transfer coefficient up to two times is beneficial for cost reduction.

  2. Brevion: the new small-scale industrial gamma irradiator

    International Nuclear Information System (INIS)

    McKinney, Dan; Perrins, Robert; Gibson, Wayne; Levesque, Daniel

    2002-01-01

    The economical processing of low-volume products has been a challenge to the gamma industry since inception, influencing customers to send their products to contractors or choose alternative technologies. With the introduction of the Brevion irradiator (patent pending), economical gamma processing of low annual volume product lines is now possible. This innovative design is specifically targeted at plants processing product volumes of up to 20,000 m 3 /yr. Brevion provides good cobalt efficiency and good dose uniformity, thus processing these volumes efficiently and economically. The Brevion facility has the distinct advantage of a low capital cost, compared to medium-sized automatic tote plants, while maintaining similar performance. Lead-time for the construction phase is also considerably shorter, resulting in significantly lower start-up costs. Companies with low-volume product lines can now achieve the control provided by in-house processing, and eliminate transportation time and costs associated with shipping products off-site

  3. STUDY ON BUILDING A SMALL-SCALE AQUAPONIC SYSTEM AND THE OUTSET OF IT

    Directory of Open Access Journals (Sweden)

    Radu Mihai Filep

    2016-07-01

    Full Text Available Building a small scale aquaponic system can be considered as a source of profit. On the same floor area two products could be yield: fish and plants (herbs, vegetables, salads, ornamentals. The small scale aquaponic system was built in the laboratory of Fisheries and Aquaculture of the Faculty of Animal Science of the University of Agronomic Sciences and Veterinary Medicine in Bucharest. It has two components, namely component of aquaculture and hydroponics component. The aquaculture component is represented by a tank with a volume of 450 l and the hydroponic component that is composed of a parallelepipedic box lined with PVC foil of 0.5 mm. PVC film’s purpose is to retain water in the hydroponic component. The parallelopipedic box was made of OSB with reinforcements made of pine timber. The substrate chosen for plant growth was river gravel with dimensions between 8 and 16 mm. The surface obtained for the plant growth was 1 m2. Water recirculation was done with a pump with adjustable flow of 300 to 1000 l / h. An aerator with two diffusers was used to assure the fish respiration and the nitrification processes. Construction costs, initialization and use of such a system are small and do not require special knowledge, tools or skills. This system can be built and used in spaces where there is no possibility of using soil for plant growth (balconies, terraces, etc.. This way one can have available herbs, vegetables and fresh fish, even in an apartments building.

  4. Effect of water purification process in radioactive content: analysis on small scale purification plants

    International Nuclear Information System (INIS)

    Lopez del Rio, H.; Quiroga S, J. C.; Davila R, J. I.; Mireles G, F.

    2009-10-01

    Water from small scale purification plants is a low cost alternative for consumers in comparison to the bottled commercial presentations. Because of its low cost per liter, the consumption of this product has increased in recent years, stimulating in turn the installation of purification systems for these small businesses. The purpose of this study was to estimate the efficiency of small scale purification systems located in the cities of Zacatecas and Guadalupe, Zacatecas, to reduce the radioactive content of water. It was measured the total alpha and beta activity in water samples of entry and exit to process, through the liquid scintillation technique. In general it was observed that the process is more efficient in removing alpha that beta activity. The fraction of total alpha activity removed varied between 27 and 100%, while between 0 and 77% of the total beta activity was removed by the analyzed plants. In all cases, the total radioactivity level was lower than the maximum permissible value settled by the official mexican standard for drinking water. (Author)

  5. Road network selection for small-scale maps using an improved centrality-based algorithm

    Directory of Open Access Journals (Sweden)

    Roy Weiss

    2014-12-01

    Full Text Available The road network is one of the key feature classes in topographic maps and databases. In the task of deriving road networks for products at smaller scales, road network selection forms a prerequisite for all other generalization operators, and is thus a fundamental operation in the overall process of topographic map and database production. The objective of this work was to develop an algorithm for automated road network selection from a large-scale (1:10,000 to a small-scale database (1:200,000. The project was pursued in collaboration with swisstopo, the national mapping agency of Switzerland, with generic mapping requirements in mind. Preliminary experiments suggested that a selection algorithm based on betweenness centrality performed best for this purpose, yet also exposed problems. The main contribution of this paper thus consists of four extensions that address deficiencies of the basic centrality-based algorithm and lead to a significant improvement of the results. The first two extensions improve the formation of strokes concatenating the road segments, which is crucial since strokes provide the foundation upon which the network centrality measure is computed. Thus, the first extension ensures that roundabouts are detected and collapsed, thus avoiding interruptions of strokes by roundabouts, while the second introduces additional semantics in the process of stroke formation, allowing longer and more plausible strokes to built. The third extension detects areas of high road density (i.e., urban areas using density-based clustering and then locally increases the threshold of the centrality measure used to select road segments, such that more thinning takes place in those areas. Finally, since the basic algorithm tends to create dead-ends—which however are not tolerated in small-scale maps—the fourth extension reconnects these dead-ends to the main network, searching for the best path in the main heading of the dead-end.

  6. PRODUCTION ELASTICITIES, RETURN TO SCALE AND ...

    African Journals Online (AJOL)

    thinkexploitsint'l

    estimates indicated that the farmers' production was in stage 1 (irrational stage) of the production ... security for a growing population is a central issue (Fu et al., 2011). ... to have attained optimal level which proper allocation of inputs can achieve. ... normally distributed with zero mean and constant variance N (0, Sv2).

  7. A greenhouse type solar dryer for small-scale dried food industries: Development and dissemination

    Energy Technology Data Exchange (ETDEWEB)

    Janjai, Serm [Solar Energy Research Laboratory, Department of Physics, Faculty of Science, Silpakorn University, Nakhon Pathom 73000 (Thailand)

    2012-07-01

    In this study, a greenhouse type solar dryer for small-scale dried food industries was developed and disseminated. The dryer consists of a parabolic roof structure covered with polycarbonate sheets on a concrete floor. The system is 8.0m in width, 20.0m in length and 3.5m in height, with a loading capacity about 1,000kg of fruits or vegetables. To ensure continuous drying operation, a 100kW-LPG gas burner was incorporated to supply hot air to the dryer during cloudy or rainy days. Nine 15-W DC fans powered by three 50-W PV modules were used to ventilate the dryer. This dryer was installed for a small-scale food industry at Nakhon Pathom in Thailand to produce osmotically dehydrated tomato. To investigate its performance, the dryer was used to dry 3 batches of osmotically dehydrated tomato. Results obtained from these experiments showed that drying air temperatures in the dryer varied from 35 C to 65 C. In addition, the drying time for these products was 2-3 days shorter than that of the natural sun drying and good quality dried products were obtained. A system of differential equations describing heat and moisture transfers during drying of osmotically dehydrated tomato was also developed. The simulated results agreed well with the experimental data. For dissemination purpose, other two units of this type of dryer were constructed and tested at two locations in Thailand and satisfactory results were obtained.

  8. Export horticulture – empowering female small-scale farmers in Kenya?

    Directory of Open Access Journals (Sweden)

    Velte, Maria

    2014-09-01

    Full Text Available Export horticulture is one of Kenya’s most dynamic sectors, with the Mount Kenya Region playing a crucial role as a result of its professional large- and small-scale production and marketing structures. The sector is consequently referred to as a “success story of African regional development” (Dolan and Sutherland 2002: 1. A qualitative case study was carried out to understand the impacts on gender inequality of the integration of horticultural smallholdings into the fresh fruit and vegetable (FFV supply chain to the European market. It will be outlined how export horticulture affects female small-scale farmers with reference to local distribution channels, the organisation of the farm as a group or an individual player, and the specific organisation of labour on the farm. The focus here is on the traditional division of labour, ownership and mobility patterns, as well as knowledge and income. The study shows that the influence of the integration in the FFV chain on gender inequality is conditioned by both the type of relations to the buyers and the internal and institutional organisation of the smallholding. Surprisingly, in some areas of the primarily male-dominated rural society, an integration in the form of outgrower schemes that resembles Gereffi et al.’s model of a captive value chain, with women farmers exclusively responsible for export production, can enhance gender equality, as women gradually gain more decision-making power and greater independence.

  9. Is Sustainable Intensification Pro-Poor? Evidence from Small-Scale Farmers in Rural Tanzania

    Directory of Open Access Journals (Sweden)

    Kathleen Brüssow

    2017-09-01

    Full Text Available The transition of farming systems to higher levels of productivity without overusing natural resources is of rising interest especially in African countries, where population growth has often been larger than past productivity increases. This paper aims to contribute to the debate on whether environmentally friendly agricultural practices are compatible with economic interests. In the context of small-scale farm households in Tanzania, the analysis focuses on Conservation Agriculture (CA at different levels of agricultural output, as CA is a promising toolbox for sustainable intensification. The results are based on a household survey conducted in 2014 with 900 randomly selected small-scale farmers in rural Tanzania, i.e., in semi-arid Dodoma and in semi-humid Morogoro region. We find that mulching is most frequently applied, followed by crop rotation, fallowing, intercropping and tree planting. Logit regressions show that CA adoption is influenced by socio-economic factors, farm characteristics and the regional context. Quantile regressions explain different levels of agricultural output through variables related to the extent of using CA. They indicate that marginalized farmers have the strongest crop income effect from an increased use of mulching. With increasing levels of agricultural output, the use of mulching remains beneficial for farmers, but the effect appears less pronounced.

  10. Small scale CHP: Alternative integration forms in the Danish energy system

    International Nuclear Information System (INIS)

    Boeg, Rasmus; Gatautis, Ramunas; Engberg Pedersen, Thomas; Schmidt, Rune; Ravn, Hans F.

    2003-01-01

    In Denmark, introduction of small scale combined heat and power (CHP) plants were part of the energy policy during the 1990's. Thus, the installed electricity capacity on this type of units multiplied approximately ten times during this decade, to constitute more than 2000 MW in 2000, or around 20% of total installed electricity capacity. The motivation for this development was mainly energy savings due to the relatively high thermal efficiency in combined production, and the associated reduction of emissions. The remuneration for the electricity delivered to the electrical network was in part based on a feed in tariff. The construction of the tariff reflected estimated benefits to the electrical system. With the liberalisation of the electricity markets this arrangement has been questioned, and it has been suggested that the differentiated payment to local CHP should be based on electricity market prising. For Denmark this would imply that the local CHP should trade the electricity on the Nordpool electricity spot market. This paper analyses parts of these two alternative ways of economic arrangements in relation to small scale CHP. First it describes the development and status till now. Then it analyses the production patterns and associated economic consequences of a change from the tariff based system to a market system. (BA)

  11. Status of small ruminant production in six selected communities in ...

    African Journals Online (AJOL)

    The study examined the status of small ruminant production in some selected communities in Delta State vis-à-vis identifying the type of people involved in it; their response to modern livestock practices and determining factors affecting their stock size. Data were obtained from 90 respondents. Results of data analysis ...

  12. Market Orientation, Innovativeness, Product Innovation, and Performance in Small Firms

    NARCIS (Netherlands)

    Verhees, F.J.H.M.; Meulenberg, M.T.G.

    2004-01-01

    Most research on market orientation, innovation and performance is related to big enterprises and small and medium-sized enterprises (SMEs). In this study a model is developed to investigate the combined effect of market orientation and innovativeness on product innovation and company performance,

  13. Interpretation of archaeological small-scale features in spectral images

    DEFF Research Database (Denmark)

    Grøn, Ole; Palmer, Susanna; Stylegar, Frans-Arne

    2011-01-01

    The paper's focus is the use of spectral images for the distinction of small archaeological anomalies on the basis of the authors work. Special attention is given to the ground-truthing perspective in the discussion of a number of cases from Norway. Different approaches to pattern-recognition are......The paper's focus is the use of spectral images for the distinction of small archaeological anomalies on the basis of the authors work. Special attention is given to the ground-truthing perspective in the discussion of a number of cases from Norway. Different approaches to pattern...

  14. Small Scale Manufacture of Replacement Crankshaft | Nyang'aya ...

    African Journals Online (AJOL)

    Local production of spares has been recognised to have direct economic advantage for the national economy in which the equipment operates. The crankshaft of a single cylinder diesel engine for which the approximate cost of a replacement is a third of the cost of a new engine was considered a prime product for local ...

  15. Improving the Product Documentation Process of a Small Software Company

    Science.gov (United States)

    Valtanen, Anu; Ahonen, Jarmo J.; Savolainen, Paula

    Documentation is an important part of the software process, even though it is often neglected in software companies. The eternal question is how much documentation is enough. In this article, we present a practical implementation of lightweight product documentation process resulting from SPI efforts in a small company. Small companies’ financial and human resources are often limited. The documentation process described here, offers a template for creating adequate documentation consuming minimal amount of resources. The key element of the documentation process is an open source web-based bugtracking system that was customized to be used as a documentation tool. The use of the tool enables iterative and well structured documentation. The solution best serves the needs of a small company with off-the-shelf software products and striving for SPI.

  16. Life cycle assessment of a small-scale anaerobic digestion plant from cattle waste

    International Nuclear Information System (INIS)

    Mezzullo, William G.; McManus, Marcelle C.; Hammond, Geoff P.

    2013-01-01

    Highlights: ► Emissions from plant manufacture contributed little towards the lifecycle impacts. ► The use phase of the AD plant could have significant impacts. ► Production of biogas and fertiliser created significant impacts. ► The consequential displacement of kerosene showed a net-benefit. ► The study concluded that it is essential to cover the digestate storage tank. -- Abstract: This paper outlines the results of a comprehensive life cycle study of the production of energy, in the form of biogas, using a small scale farm based cattle waste fed anaerobic digestion (AD) plant. The life cycle assessment (LCA) shows that in terms of environmental and energy impact the plant manufacture contributes very little to the whole life cycle impacts. The results show that compared with alternative energy supply the production and use of biogas is beneficial in terms of greenhouse gases and fossil fuel use. This is mainly due to the replacement of the alternative, kerosene, and from fertiliser production from the AD process. However, these benefits come at a cost to ecosystem health and the production of respiratory inorganics. These were found to be a result of ammonia emissions during the production phase of the biogas. These damages can be significantly reduced if further emission control measures are undertaken.

  17. Economic and financial viability of small-scale dairy systems in central Mexico: economic scenario 2010-2018.

    Science.gov (United States)

    Posadas-Domínguez, R R; Callejas-Juárez, N; Arriaga-Jordán, C M; Martínez-Castañeda, F E

    2016-12-01

    A simulation Monte Carlo model was used to assess the economic and financial viability of 130 small-scale dairy farms in central Mexico, through a Representative Small-Scale Dairy Farm. Net yields were calculated for a 9-year planning horizon by means of simulated values for the distribution of input and product prices taking 2010 as base year and considering four scenarios which were compared against the scenario of actual production. The other scenarios were (1) total hiring in of needed labour; (2) external purchase of 100 % of inputs and (3) withdrawal of subsidies to production. A stochastic modelling approach was followed to determine the scenario with the highest economic and financial viability. Results show a viable economic and financial situation for the real production scenario, as well as the scenarios for total hiring of labour and of withdrawal of subsidies, but the scenario when 100 % of feed inputs for the herd are bought-in was not viable.

  18. Analysis of small-scale biogas utilization systems on Ontario cattle farms

    International Nuclear Information System (INIS)

    White, Andrew J.; Kirk, Donald W.; Graydon, John W.

    2011-01-01

    The production of biogas through the anaerobic digestion of cattle manure and its subsequent use in the generation of electricity on larger farms in Ontario is currently economically attractive. This is a result of the Ontario Feed-In Tariff (FIT) program, which provides incentivized rates for the production of electricity from biogas. Although larger farms can take advantage of the higher rates for electricity, there are substantially more smaller farms for which individually designed and engineered biogas systems would be prohibitively expensive. By employing the concept of modular biogas plants, this analysis evaluates the economics of small-scale biogas utilization systems. Dairy farms with at least 33 animals and beef farms with at least 78 animals can operate economically attractive biogas systems. This analysis shows that approximately 9000 additional Ontario cattle farms would be able to take advantage of the FIT program, which would add 120 MW e of renewable energy capacity to the Ontario electrical grid. (author)

  19. Small-scale Magnetic Flux Emergence in the Quiet Sun

    Science.gov (United States)

    Moreno-Insertis, F.; Martinez-Sykora, J.; Hansteen, V. H.; Muñoz, D.

    2018-06-01

    Small bipolar magnetic features are observed to appear in the interior of individual granules in the quiet Sun, signaling the emergence of tiny magnetic loops from the solar interior. We study the origin of those features as part of the magnetoconvection process in the top layers of the convection zone. Two quiet-Sun magnetoconvection models, calculated with the radiation-magnetohydrodynamic (MHD) Bifrost code and with domain stretching from the top layers of the convection zone to the corona, are analyzed. Using 3D visualization as well as a posteriori spectral synthesis of Stokes parameters, we detect the repeated emergence of small magnetic elements in the interior of granules, as in the observations. Additionally, we identify the formation of organized horizontal magnetic sheets covering whole granules. Our approach is twofold, calculating statistical properties of the system, like joint probability density functions (JPDFs), and pursuing individual events via visualization tools. We conclude that the small magnetic loops surfacing within individual granules in the observations may originate from sites at or near the downflows in the granular and mesogranular levels, probably in the first 1 or 1.5 Mm below the surface. We also document the creation of granule-covering magnetic sheet-like structures through the sideways expansion of a small subphotospheric magnetic concentration picked up and pulled out of the interior by a nascent granule. The sheet-like structures that we found in the models may match the recent observations of Centeno et al.

  20. experiences and perceptions of black small- scale irrigation farmers ...

    African Journals Online (AJOL)

    farmers will hopefully be able to utilise the research findings (consolidated in an easily ... When political independence in Zimbabwe was achieved in 1980, the new government ... According to Tomlinson (1994:16) the percentage of the urban ..... As a result, many small gardens are utilised for the purpose of vegetable.

  1. Scaling behavior of jet production at CDF

    International Nuclear Information System (INIS)

    Behrends, S.

    1992-11-01

    Inclusive jet cross-sections have been measured in bar pp collisions at √s = 546 and 1800 GeV, using the CDF detector at the Fermilab Tevatron. The ratio of jet cross-sections is compared to predictions from simple scaling and 0(α s 3 ) QCD

  2. Scaling behavior of jet production at CDF

    Energy Technology Data Exchange (ETDEWEB)

    Behrends, S. [Brandeis Univ., Waltham, MA (United States). Dept. of Physics; The CDF Collaboration

    1992-11-01

    Inclusive jet cross-sections have been measured in {bar p}p collisions at {radical}s = 546 and 1800 GeV, using the CDF detector at the Fermilab Tevatron. The ratio of jet cross-sections is compared to predictions from simple scaling and 0({alpha}{sub s{sup 3}}) QCD.

  3. Scaling and jumping: Gravity loses grip on small jumpers

    NARCIS (Netherlands)

    Scholz, M.N.; Bobbert, M.F.; van Soest, A.J.

    2006-01-01

    There are several ways to quantify jumping performance, a common definition being the height gained by the body's centre of mass (CM) in the airborne phase. Under this definition, jump height is determined by take-off velocity. According to the existing literature on jumping and scaling, take-off

  4. Velocity of small-scale auroral ionospheric current systems over ...

    Indian Academy of Sciences (India)

    At the latter times, triangulation with 3 uxgate magnetometers located at the vertices of a suitable triangle provides a means of monitoring mobile auroral ionospheric current systems over Maitri. The spacing between the magnetometers is typically kept at 75-200 km, keeping in mind the scale-sizes of ∼100 km for these ...

  5. Gravitational waves in axion inflation: implications for CMB and small-scales interferometer measurements

    Science.gov (United States)

    Unal, Caner; Peloso, Marco; Sorbo, Lorenzo; Garcia-Bellido, Juan

    2017-01-01

    A strong experimental effort is ongoing to detect the primordial gravitational waves (GW) generated during inflation from their impact on the Cosmic Microwave Background (CMB). This effort is motivated by the direct relation between the amplitude of GW signal and the energy scale of inflation, in the standard case of GW production from vacuum. I will discuss the robustness of this relation and the conditions under which particle production mechanisms during inflation can generate a stronger GW signal than the vacuum one. I will present a concrete model employing a coupling between a rolling axion and a gauge field, that can produce a detectable GW signal for an arbitrarily small inflation scale, respecting bounds from back-reaction, perturbativity, and the gaussianity of the measured density perturbations. I will show how the GW produced by this mechanism can be distinguished from the vacuum ones by their spectral dependence and statistical properties. I will finally discuss the possibility of detecting an inflationary GW signal at terrestrial (AdvLIGO) and space (LISA) interferometers. Such experiments are sensitive to the modes much smaller than the ones corresponding to CMB and Large Scale Structure, presenting a unique observational window on the final stages of inflation. The work of C.U. is s supported by a Doctoral Dissertation Fellowship from the Graduate School of the University of Minnesota.

  6. Modelling aggregation on the large scale and regularity on the small scale in spatial point pattern datasets

    DEFF Research Database (Denmark)

    Lavancier, Frédéric; Møller, Jesper

    We consider a dependent thinning of a regular point process with the aim of obtaining aggregation on the large scale and regularity on the small scale in the resulting target point process of retained points. Various parametric models for the underlying processes are suggested and the properties...

  7. The Impact of Small Scale Mining on Irrigation Water Quality in ...

    African Journals Online (AJOL)

    Small scale mining is a major threat to water resources and agricultural activities in most mining communities across Ghana. This study investigated the effect of small scale mining on the quality of water for irrigation from some selected sites along a river and a reservoir which was used as a control. The physical and ...

  8. Methodological foundations of evaluation of effectiveness indicators of small-scale business activities

    Directory of Open Access Journals (Sweden)

    Ivanova T.

    2013-01-01

    Full Text Available The methodological approach to the measurement of financial indicators of small-scale enterprises has been developed. It enables to secure the comparability of financial condition indicators and the results of small-scale enterprise activities, and also to develop the methods of vertical integral estimate calculation at separate aspects of financial condition and the results of smallscale enterprise activities.

  9. Enhancing stewardship in Latin America and Caribbean small-scale fisheries : challenges and opportunities

    NARCIS (Netherlands)

    Gasalla, M.A.; de Castro, F.

    2016-01-01

    This thematic series, entitled “Enhancing Stewardship in Latin America and Caribbean Small-Scale Fisheries”, emerged as part of a joint effort to bridge Latin-American scholars interested in networking on small-scale fisheries in the region. Built on results presented at two meetings (‘Too Big to

  10. Socio-technical study of small-scale gold mining in Suriname

    NARCIS (Netherlands)

    Seccatore, J; de Theije, M.E.M.

    2017-01-01

    Small-scale gold mining is Suriname’s main economic sector, producing about two thirds of the nation’s gold. Despite this, the sector is only very loosely regulated and most small-scale mining activities are informal. Surinamese miners are only a minority: the majority are Brazilian migrants, who

  11. Category, narrative and value in the governance of small-scale fisheries

    NARCIS (Netherlands)

    Johnson, D.S.

    2006-01-01

    Since the 1970s, small-scale fisheries have had an important place in fisheries social science and in fisheries management. While there has been substantial discussion of what constitutes the category of small-scale fisheries, its considerable ambiguity is nevertheless often passed over. This paper

  12. Small-Scale vertical axis wind turbine design

    OpenAIRE

    Castillo Tudela, Javier

    2011-01-01

    The thesis focuses on the design of a small vertical axis wind turbine rotor with solid wood as a construction material. The aerodynamic analysis is performed implementing a momentum based model on a mathematical computer program. A three bladed wind turbine is proposed as candidate for further prototype testing after evaluating the effect of several parameters in turbine efficiency, torque and acceleration. The results obtained indicate that wood is a suitable material for rotor cons...

  13. The meaning of venture capital for financing small scale entrepreneurship

    OpenAIRE

    Robnik, Lidija

    2015-01-01

    Due to the appearance of new knowledge and managerial approaches, entrepreneurship has developed substantially and the career of the entrepreneur has become more attractive. Venture capital has become an important source for financing the growth of small enterprises. Venture capital funds are a form of financing intended for prospective dynamic companies that cannot obtain financing from banks. Venture capital takes the form of proprietary capital since it enters the company as a co-owner for...

  14. Up-Scaling Production of Carboxymethyl Starch

    International Nuclear Information System (INIS)

    Mohd Hafiz Abdul Nasir; Zainon Othman; Kamaruddin Hashim; Siti Khadijah Abu Hadin; Nurul Nadia Shaaban

    2015-01-01

    Carboxymethyl starch (CMS) is a starch derivative formed by its reaction with sodium monochloroacetate which consist of OH-groups that are partially or completely replaced by ether substitution. Characteristic of CMSS defined by the degree of substitution (DS). DS is defined as the average number of substituents per anhydro glucose unit (AGU), the monomer unit of starch. The upgrading of CMSS production from 10L to 30L requires several experiments with different variable such as amount NaOH, amount of Sago Starch and reaction time. Each will give different DS. Quality control for the product cover moisture, viscosity and paste clarity. Therefore, SOP has been established to control the quality final product. (author)

  15. Technologies for small scale wood-fueled combined heat and power systems

    Energy Technology Data Exchange (ETDEWEB)

    Houmann Jakobsen, H.; Houmoeller, S.; Thaaning Pedersen, L.

    1998-01-01

    The aim of this study is to describe and compare different technologies for small cogeneration systems (up to 2-3 MW{sub e}), based on wood as fuel. For decentralized cogeneration, i.e. for recovering energy from saw mill wood wastes or heat supply for small villages, it is vital to know the advantages and disadvantages of the different technologies. Also, for the decision-makers it is of importance to know the price levels of the different technologies. A typical obstacle for small wood cogeneration systems is the installation costs. The specific price (per kW) is usually higher than for larger plants or plants using fossil fuels. For a saw mill choosing between cogeneration and simple heat production, however, the larger installation costs are counter weighed by the sale of electricity, while the fuel consumption is the same. Whether it is profitable or not to invest in cogeneration is often hard to decide. For many years small wood cogeneration systems have been too expensive, leading to the construction of only heat producing systems due to too high price levels of small steam turbines. In recent years a great deal of effort has been put into research and developing of new technologies to replace this traditional steam turbine. Among these are: Steam engines; Stirling engines; Indirectly fired gas turbines; Pressurized down draft combustion. Along with the small scale traditional steam turbines, these technologies will be evaluated in this study. When some or all these technologies are fully developed and commercial, a strong means of reducing the strain on the environment and the greenhouse effect will be available, as the total efficiency is high (up to 90%) and wood is an energy source in balance with nature. (au) EFP-95. 19 refs.

  16. Unintegrated sea quark at small x and vector boson production

    CERN Document Server

    Hautmann, F; Jung, H

    2012-01-01

    Parton-shower event generators that go beyond the collinear-ordering approximation at small x have so far included only gluon and valence quark channels at transverse momentum dependent level. In this contribution we provide a denition of a transverse momentum depend (TMD) sea quark distribution valid in the small x region, which is based on the TMD gluon-to-quark splitting function. As an example process we consider vector boson production in the forward direction of one of the protons. The qq ! Z matrix element (with one o-shell quark) is calculated in an explicit gauge invariant way, making use of high energy factorization.

  17. Abatement of emissions from small-scale combustion of biofuels

    International Nuclear Information System (INIS)

    Cowburn, D.A.; Holtham, R.D.

    1999-01-01

    This report summarises the findings of a study examining the feasibility of designing a free-standing stove for heating a room using a downburning combustion system with air introduced above the bed of the fire to minimise the deposition of tar on the glass door of the stove. Details of the construction and operation of the appliance and the testing methods are given. Emission measurements, modeling, and work on pre-production of the prototype and production model stoves are reported. A paper on the development of low smoke stoves for domestic wood use is presented in an appendix. (UK)

  18. Scaling criteria and an assessment of Semiscale Mod-3 scaling for small-break loss-of-coolant transients

    International Nuclear Information System (INIS)

    Larson, T.K.; Anderson, J.L.; Shimeck, D.J.

    1982-01-01

    Various methods of scaling fluid thermal-hydraulic test facilities and their relative merits and disadvantages are examined in light of nuclear reactor safety considerations. Particular emphasis is placed on examination of the scaling of the Semiscale Mod-3 system and determination of thermal-hydraulic phenomena thought to be important during a small break loss-of-coolant accident in a pressurized water nuclear reactor. The influence of geometric and dynamic scaling concerns in the Mod-3 system on small break behavior are addressed from an engineering viewpoint and corrective measures contemplated or required to make results from Semiscale tests more meaningful relative to expected PWR response are discussed

  19. Optimal Product Variety, Scale Effects and Growth

    NARCIS (Netherlands)

    de Groot, H.L.F.; Nahuis, R.

    1997-01-01

    We analyze the social optimality of growth and product variety in a model of endogenous growth. The model contains two sectors, one assembly sector producing a homogenous consumption good, and one intermediate goods sector producing a differentiated input used in the assembly sector. Growth results

  20. ECONOMIES OF SCALE AND PRODUCTION EFFICIENCY IN ...

    African Journals Online (AJOL)

    Admin

    high rate of population growth of 2.83% (FOS, 1996). The apparent disparity between the rate of food production and demand for food in Nigeria has led to: (i) a food demand-supply gap thus leading to a widening gap between domestic food supply and the total food requirement; (ii) an increased food importation and (iii).

  1. Medium/small-scale computers HITACHI M-620, M-630, and M-640 systems: the aim of development and characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Oshima, N; Saiki, Y; Sunaga, K [Hitachi, Ltd., Tokyo (Japan)

    1990-10-01

    The medium/small-scale HITACHI M-620, M-630, and M-640 computer systems are outlined. Every system is featured by the configuration usable as a medium or small-scale host computer in offices, the function connectable with large-scale host computers, the performance of 5-50 times those of conventional office computers, easy operation and fast processing. As features of the hardware, the one-board CPU and small integrated cubicle structure containing the CPU board, high-speed large-capacity magnetic disk storage device, various kinds of controllers and others are illustrated. As features of the software, the OS (VOS K) featured by the virtual data space control (VDSA) and relational database (RDB) functions, EAGLE/4GL (effective approach to achieving high level software productivity/4th generation language), STEP (self training environmental support program) and simple end user language ACE3/E2 are outlined. 7 figs.

  2. Analysis of environmental issues related to small-scale hydroelectric development. III. Water level fluctuation

    Energy Technology Data Exchange (ETDEWEB)

    Hildebrand, S.G. (ed.)

    1980-10-01

    Potential environmental impacts in reservoirs and downstream river reaches below dams that may be caused by the water level fluctuation resulting from development and operation of small scale (under 25MW) hydroelectric projects are identified. The impacts discussed will be of potential concern at only those small-scale hydroelectric projects that are operated in a store and release (peaking) mode. Potential impacts on physical and chemical characteristics in reservoirs resulting from water level fluctuation include resuspension and redistribution of bank and bed sediment; leaching of soluble organic matter from sediment in the littoral zone; and changes in water quality resulting from changes in sediment and nutrient trap efficiency. Potential impacts on reservoir biota as a result of water level fluctuation include habitat destruction and the resulting partial or total loss of aquatic species; changes in habitat quality, which result in reduced standing crop and production of aquatic biota; and possible shifts in species diversity. The potential physical effects of water level fluctuation on downstream systems below dams are streambed and bank erosion and water quality problems related to resuspension and redistribution of these materials. Potential biological impacts of water level fluctuation on downstream systems below dams result from changes in current velocity, habitat reduction, and alteration in food supply. These alterations, either singly or in combination, can adversely affect aquatic populations below dams. The nature and potential significance of adverse impacts resulting from water level fluctuation are discussed. Recommendations for site-specific evaluation of water level fluctuation at small-scale hydroelectric projects are presented.

  3. Optimization of large scale food production using Lean Manufacturing principles

    DEFF Research Database (Denmark)

    Engelund, Eva Høy; Friis, Alan; Breum, Gitte

    2009-01-01

    This paper discusses how the production principles of Lean Manufacturing (Lean) can be applied in a large-scale meal production. Lean principles are briefly presented, followed by a field study of how a kitchen at a Danish hospital has implemented Lean in the daily production. In the kitchen...... not be negatively affected by the rationalisation of production procedures. The field study shows that Lean principles can be applied in meal production and can result in increased production efficiency and systematic improvement of product quality without negative effects on the working environment. The results...... show that Lean can be applied and used to manage the production of meals in the kitchen....

  4. Accelerating research into bio-based FDCA-polyesters by using small scale parallel film reactors.

    Science.gov (United States)

    Gruter, Gert-Jan M; Sipos, Laszlo; Adrianus Dam, Matheus

    2012-02-01

    High Throughput experimentation has been well established as a tool in early stage catalyst development and catalyst and process scale-up today. One of the more challenging areas of catalytic research is polymer catalysis. The main difference with most non-polymer catalytic conversions is the fact that the product is not a well defined molecule and the catalytic performance cannot be easily expressed only in terms of catalyst activity and selectivity. In polymerization reactions, polymer chains are formed that can have various lengths (resulting in a molecular weight distribution rather than a defined molecular weight), that can have different compositions (when random or block co-polymers are produced), that can have cross-linking (often significantly affecting physical properties), that can have different endgroups (often affecting subsequent processing steps) and several other variations. In addition, for polyolefins, mass and heat transfer, oxygen and moisture sensitivity, stereoregularity and many other intrinsic features make relevant high throughput screening in this field an incredible challenge. For polycondensation reactions performed in the melt often the viscosity becomes already high at modest molecular weights, which greatly influences mass transfer of the condensation product (often water or methanol). When reactions become mass transfer limited, catalyst performance comparison is often no longer relevant. This however does not mean that relevant experiments for these application areas cannot be performed on small scale. Relevant catalyst screening experiments for polycondensation reactions can be performed in very efficient small scale parallel equipment. Both transesterification and polycondensation as well as post condensation through solid-stating in parallel equipment have been developed. Next to polymer synthesis, polymer characterization also needs to be accelerated without making concessions to quality in order to draw relevant conclusions.

  5. Comparative Study of Laboratory-Scale and Prototypic Production-Scale Fuel Fabrication Processes and Product Characteristics

    International Nuclear Information System (INIS)

    Marshall, Douglas W.

    2014-01-01

    An objective of the High Temperature Gas Reactor fuel development and qualification program for the United States Department of Energy has been to qualify fuel fabricated in prototypic production-scale equipment. The quality and characteristics of the tristructural isotropic (TRISO) coatings on fuel kernels are influenced by the equipment scale and processing parameters. The standard deviations of some TRISO layer characteristics were diminished while others have become more significant in the larger processing equipment. The impact on statistical variability of the processes and the products, as equipment was scaled, are discussed. The prototypic production-scale processes produce test fuels meeting all fuel quality specifications. (author)

  6. Estimation of small-scale hydroelectric power plant costs

    International Nuclear Information System (INIS)

    Santos, Afonso Henriques Moreira; Silva, Benedito Claudio da; Magalhaes, Ricardo Nogueira

    2010-01-01

    Changes in Brazilian energy scenario through last years such as increase of demand and search for clean and economically feasible renewable energy sources, has stimulated investors to small hydro power plants (SHP) sector. Such characteristics together with several economic incentives, legal and regulatory mechanisms also, have helped and stimulated building of new plants of this kind and have attracted a great number of investors to this sector. Study of costs analysis and feasibility of investments is a study which has been used since long time in SHP business market as several preliminary studies previous to civil project have significant costs which lead us to count with a feasibility analysis from the very beginning of studies, exactly what is suggested in the present methodology. Such feasibility analysis, in the common patterns where basic unit costs of each input remain outstanding, would be very complex due to great difficulty in obtaining information at initial phase of project. In this direction this study brings a contribution for investors as well as for designers of small hydro power plants since it outlines a link between physical and energetic characteristics of small hydro power plant in its total cost. Such link is based in available physical characteristics in initial phase of the project, making possible a previous comparison between arrangements of a central or even the comparison of return of investment between different plants. The resulting benefit being the possibility of choosing centrals with greater economic feasibility disregarding bad undertakings or arrangements with more expressive cost. Final result gives a better delay in return of investment, helps in power, arrangements more optimized and in saving time as well, reducing costs of undertakings. Due to large number of SHP arrangements, we chose for this study the most common in Brazil, plant of medium and large fall, shunting line balance chimney and low pressure conduit. (author)

  7. Pesticide safety practice and its determinants among small scale ...

    African Journals Online (AJOL)

    Background: Strategies to achieve the millennium agricultural development goals include increased use of pesticides to increase agricultural production in poor countries. However, the increased availability and use of such chemicals need to be paralleled with national and personal level practices to maximize safety for ...

  8. Work Related Injuries and Associated Factors among Small Scale ...

    African Journals Online (AJOL)

    user

    smoking, alcohol consumption, working for more than 8 hours and working at night had high odds of occupational injuries. Use of ... equivalent to 4 % of the world's gross national product. The impact ... required them to miss a week of work (9).

  9. Incorporating rural users in small-scale growing container ...

    African Journals Online (AJOL)

    If the users of products developed for them are incorporated in the design process it is more likely that an acceptable and usable outcome will be achieved. A user-centred design process places a stronger emphasis on user involvement. In cases where the users live far away from the design facilities, certain logistical and ...

  10. An accurate and computationally efficient small-scale nonlinear FEA of flexible risers

    OpenAIRE

    Rahmati, MT; Bahai, H; Alfano, G

    2016-01-01

    This paper presents a highly efficient small-scale, detailed finite-element modelling method for flexible risers which can be effectively implemented in a fully-nested (FE2) multiscale analysis based on computational homogenisation. By exploiting cyclic symmetry and applying periodic boundary conditions, only a small fraction of a flexible pipe is used for a detailed nonlinear finite-element analysis at the small scale. In this model, using three-dimensional elements, all layer components are...

  11. Pricing Power of Agricultural Products under the Background of Small Peasant Management and Information Asymmetry

    Institute of Scientific and Technical Information of China (English)

    Dexuan LI

    2016-01-01

    From the background of small peasant management and information asymmetry,this paper introduced the middle profit sharing model and discussed influence factors and ownership of pricing power of agricultural products. It obtained following results:( i) the transaction scale has positive effect on farmer’s pricing power of agricultural products,while the competitor’s transaction scale has negative effect on it,so does the cost for information search;( ii) under the condition of small peasant management system,farmer is in a relatively weak position in the distribution of pricing power of agricultural products,due to factors such as small transaction scale,information asymmetry and farmer’s weak negotiation ability;( iii) through cooperative game,farmer and buyers can share cooperative surplus at the agreed ratio;( iv) the introduction of self-organizing specialized farmers cooperatives is favorable for solving the problem of pricing power of agricultural products,and possible problems,such as " collective action dilemma" and " fake cooperatives" in the cooperative development process can be solved by internal and external division of labor and specialization of cooperatives.

  12. Notes on a Dramaturgical Analysis of Unequal Small-Scale Corruption Experiences

    OpenAIRE

    Edgar Daniel Manchinelly Mota

    2017-01-01

    In the last two decades, corruption has emerged as a relevant subject on a worldwide scale, because of its negative effects on the economy and State institutions, among other things. Research has focused on the macro aspects of corruption, emphasizing its causes and consequences. However, small-scale corruption has not been studied in such detail. This document proposes a theoretical-methodological framework for a dramaturgical analysis of small-scale corruption, with the aim of demonstrating...

  13. Stochastic Independence as a Resource for Small-Scale Thermodynamics

    Science.gov (United States)

    Lostaglio, Matteo; Mueller, Markus P.; Pastena, Michele

    It is well-known in thermodynamics that the creation of correlations costs work. It seems then a truism that if a thermodynamic transformation A --> B is impossible, so will be any transformation that in sending A to B also correlates among them some auxiliary systems C. Surprisingly, we show that this is not the case for non-equilibrium thermodynamics of microscopic systems. On the contrary, the creation of correlations greatly extends the set of accessible states, to the point that we can perform on individual systems and in a single shot any transformation that would otherwise be possible only if the number of systems involved was very large. We also show that one only ever needs to create a vanishingly small amount of correlations (as measured by mutual information) among a small number of auxiliary systems (never more than three). The many, severe constraints of microscopic thermodynamics are reduced to the sole requirement that the non-equilibrium free energy decreases in the transformation. This shows that, in principle, reliable extraction of work equal to the free energy of a system can be performed by microscopic engines.

  14. Stochastic Independence as a Resource in Small-Scale Thermodynamics

    Science.gov (United States)

    Lostaglio, Matteo; Müller, Markus P.; Pastena, Michele

    2015-10-01

    It is well known in thermodynamics that the creation of correlations costs work. It seems then a truism that if a thermodynamic transformation A →B is impossible, so will be any transformation that in sending A to B also correlates among them some auxiliary systems C . Surprisingly, we show that this is not the case for nonequilibrium thermodynamics of microscopic systems. On the contrary, the creation of correlations greatly extends the set of accessible states, to the point that we can perform on individual systems and in a single shot any transformation that would otherwise be possible only if the number of systems involved was very large. We also show that one only ever needs to create a vanishingly small amount of correlations (as measured by mutual information) among a small number of auxiliary systems (never more than three). The many, severe constraints of microscopic thermodynamics are reduced to the sole requirement that the nonequilibrium free energy decreases in the transformation. This shows that, in principle, reliable extraction of work equal to the free energy of a system can be performed by microscopic engines.

  15. Small Scale Variability and the Problem of Data Validation

    Science.gov (United States)

    Sparling, L. C.; Avallone, L.; Einaudi, Franco (Technical Monitor)

    2000-01-01

    Numerous measurements taken with a variety of airborne, balloon borne and ground based instruments over the past decade have revealed a complex multiscaled 3D structure in both chemical and dynamical fields in the upper troposphere/lower stratosphere. The variability occurs on scales that are well below the resolution of satellite measurements, leading to problems in measurement validation. We discuss some statistical ideas that can shed some light on the contribution of the natural variability to the inevitable differences in correlative measurements that are not strictly colocated, or that have different spatial resolution.

  16. Hydrological Modelling of Small Scale Processes in a Wetland Habitat

    DEFF Research Database (Denmark)

    Johansen, Ole; Jensen, Jacob Birk; Pedersen, Morten Lauge

    2009-01-01

    Numerical modelling of the hydrology in a Danish rich fen area has been conducted. By collecting various data in the field the model has been successfully calibrated and the flow paths as well as the groundwater discharge distribution have been simulated in details. The results of this work have...... shown that distributed numerical models can be applied to local scale problems and that natural springs, ditches, the geological conditions as well as the local topographic variations have a significant influence on the flow paths in the examined rich fen area....

  17. Quantitative approach to small-scale nonequilibrium systems

    DEFF Research Database (Denmark)

    Dreyer, Jakob K; Berg-Sørensen, Kirstine; Oddershede, Lene B

    2006-01-01

    In a nano-scale system out of thermodynamic equilibrium, it is important to account for thermal fluctuations. Typically, the thermal noise contributes fluctuations, e.g., of distances that are substantial in comparison to the size of the system and typical distances measured. If the thermal...... propose an approximate but quantitative way of dealing with such an out-of-equilibrium system. The limits of this approximate description of the escape process are determined through optical tweezers experiments and comparison to simulations. Also, this serves as a recipe for how to use the proposed...

  18. Designing a Frost Forecasting Service for Small Scale Tea Farmers in East Africa

    Science.gov (United States)

    Adams, E. C.; Nyaga, J. W.; Ellenburg, W. L.; Limaye, A. S.; Mugo, R. M.; Flores Cordova, A. I.; Irwin, D.; Case, J.; Malaso, S.; Sedah, A.

    2017-12-01

    Kenya is the third largest tea exporter in the world, producing 10% of the world's black tea. Sixty percent of this production occurs largely by small scale tea holders, with an average farm size of 1.04 acres, and an annual net income of 1,075. According to a recent evaluation, a typical frost event in the tea growing region causes about 200 dollars in losses which can be catastrophic for a small holder farm. A 72-hour frost forecast would provide these small-scale tea farmers with enough notice to reduce losses by approximately $80 annually. With this knowledge, SERVIR, a joint NASA-USAID initiative that brings Earth observations for improved decision making in developing countries, sought to design a frost monitoring and forecasting service that would provide farmers with enough lead time to react to and protect against a forecasted frost occurrence on their farm. SERVIR Eastern and Southern Africa, through its implementing partner, the Regional Centre for Mapping of Resources for Development (RCMRD), designed a service that included multiple stakeholder engagement events whereby stakeholders from the tea industry value chain were invited to share their experiences so that the exact needs and flow of information could be identified. This unique event allowed enabled the design of a service that fit the specifications of the stakeholders. The monitoring service component uses the MODIS Land Surface Temperature product to identify frost occurrences in near-real time. The prediction component, currently under testing, uses the 2-m air temperature, relative humidity, and 10-m wind speed from a series of high-resolution Weather Research and Forecasting (WRF) numerical weather prediction model runs over eastern Kenya as inputs into a frost prediction algorithm. Accuracy and sensitivity of the algorithm is being assessed with observations collected from the farmers using a smart phone app developed specifically to report frost occurrences, and from data shared through

  19. Polarized 3 parton production in inclusive DIS at small x

    Energy Technology Data Exchange (ETDEWEB)

    Ayala, Alejandro [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Apartado Postal 70-543, Ciudad de México 04510 (Mexico); Centre for Theoretical and Mathematical Physics, and Department of Physics, University of Cape Town, Rondebosch 7700 (South Africa); Hentschinski, Martin, E-mail: hentschinski@correo.nucleares.unam.mx [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Apartado Postal 70-543, Ciudad de México 04510 (Mexico); Facultad de Ciencias Físico Matemáticas, Benemérita Universidad Autónoma de Puebla, Puebla 1152 (Mexico); Jalilian-Marian, Jamal [Department of Natural Sciences, Baruch College, CUNY, 17 Lexington Avenue, New York, NY 10010 (United States); CUNY Graduate Center, 365 Fifth Avenue, New York, NY 10016 (United States); Tejeda-Yeomans, Maria Elena [Departamento de Física, Universidad de Sonora, Boulevard Luis Encinas J. y Rosales, Colonia Centro, Hermosillo, Sonora 83000 (Mexico)

    2016-10-10

    Azimuthal angular correlations between produced hadrons/jets in high energy collisions are a sensitive probe of the dynamics of QCD at small x. Here we derive the triple differential cross section for inclusive production of 3 polarized partons in DIS at small x. The target proton or nucleus is described using the Color Glass Condensate (CGC) formalism. The resulting expressions are used to study azimuthal angular correlations between produced partons in order to probe the gluon structure of the target hadron or nucleus. Our analytic expressions can also be used to calculate the real part of the Next to Leading Order (NLO) corrections to di-hadron production in DIS by integrating out one of the three final state partons.

  20. Polarized 3 parton production in inclusive DIS at small x

    International Nuclear Information System (INIS)

    Ayala, Alejandro; Hentschinski, Martin; Jalilian-Marian, Jamal; Tejeda-Yeomans, Maria Elena

    2016-01-01

    Azimuthal angular correlations between produced hadrons/jets in high energy collisions are a sensitive probe of the dynamics of QCD at small x. Here we derive the triple differential cross section for inclusive production of 3 polarized partons in DIS at small x. The target proton or nucleus is described using the Color Glass Condensate (CGC) formalism. The resulting expressions are used to study azimuthal angular correlations between produced partons in order to probe the gluon structure of the target hadron or nucleus. Our analytic expressions can also be used to calculate the real part of the Next to Leading Order (NLO) corrections to di-hadron production in DIS by integrating out one of the three final state partons.

  1. Polarized 3 parton production in inclusive DIS at small x

    Directory of Open Access Journals (Sweden)

    Alejandro Ayala

    2016-10-01

    Full Text Available Azimuthal angular correlations between produced hadrons/jets in high energy collisions are a sensitive probe of the dynamics of QCD at small x. Here we derive the triple differential cross section for inclusive production of 3 polarized partons in DIS at small x. The target proton or nucleus is described using the Color Glass Condensate (CGC formalism. The resulting expressions are used to study azimuthal angular correlations between produced partons in order to probe the gluon structure of the target hadron or nucleus. Our analytic expressions can also be used to calculate the real part of the Next to Leading Order (NLO corrections to di-hadron production in DIS by integrating out one of the three final state partons.

  2. Amplification of Marzagao small scale hydroelectric power plant; Ampliacao da PCH de Marzagao

    Energy Technology Data Exchange (ETDEWEB)

    Zeller, A.R.; Porto, D.S.; Pinto, F.S. [Leme Engenharia, MG (Brazil); Melo, A.U.; Almeida, A.M.; Pereira, D.R. [Fertiligas Industria e Comercio Ltda., MG (Brazil)

    1991-12-31

    This work presents the modernization and power augmentation of Marzagao small scale hydroelectric power plant. In order that the costs of the project be compatible to the total of investments in the project, it was necessary the adoption of methodologies and time scales different from those used for large and medium scale hydroelectric power plants 5 figs.

  3. Toyota production system beyond large-scale production

    CERN Document Server

    Ohno, Taiichi

    1998-01-01

    In this classic text, Taiichi Ohno--inventor of the Toyota Production System and Lean manufacturing--shares the genius that sets him apart as one of the most disciplined and creative thinkers of our time. Combining his candid insights with a rigorous analysis of Toyota's attempts at Lean production, Ohno's book explains how Lean principles can improve any production endeavor. A historical and philosophical description of just-in-time and Lean manufacturing, this work is a must read for all students of human progress. On a more practical level, it continues to provide inspiration and instruction for those seeking to improve efficiency through the elimination of waste.

  4. Investigation of the scale for dividing small earthquake regions

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Y.; Zhang, H.

    1980-01-22

    In view of the fact that the upper layer of soil has a greater effect on earthquake damage than the lower layers, the area of an inverted triangle is used for averaging the effects of soils of different depths on the composite shear strength, G/sub j/ x 10/sup 3/ tons/m/sup 2/; where G/sub j/ is the composite shear strength of the jth drill hole. For the purpose of supporting the reconstruction of Tangshan, this technique was used in 1977 by the Institute of Engineering Mechanics Chinese Academy of Sciences and the Institute of Surveying Chinese Academy of Architecture to proceed with small area classification of Fengrun, which is a northern suburb of Tangshan. The result basically agrees with the classification data of engineering geology.

  5. Small Reservoir Impact on Simulated Watershed-Scale Nutrient Yield

    Directory of Open Access Journals (Sweden)

    Shane J. Prochnow

    2007-01-01

    Full Text Available The soil and water assessment tool (SWAT is used to assess the influence of small upland reservoirs (PL566 on watershed nutrient yield. SWAT simulates the impact of collectively increasing and decreasing PL566 magnitudes (size parameters on the watershed. Totally removing PL566 reservoirs results in a 100% increase in total phosphorus and an 82% increase in total nitrogen, while a total maximum daily load (TMDL calling for a 50% reduction in total phosphorus can be achieved with a 500% increase in the magnitude of PL566s in the watershed. PL566 reservoirs capture agriculture pollution in surface flow, providing long-term storage of these constituents when they settle to the reservoir beds. A potential strategy to reduce future downstream nutrient loading is to enhance or construct new PL566 reservoirs in the upper basin to better capture agricultural runoff.

  6. New approach to small scale power could light up much of the developing world

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, J.

    2011-01-15

    The modern conveniences requiring electricity have been out of reach for almost half of the world's population because they live too far from the grid. Innovative technology combined with creative new business models could significantly improve the quality of life for millions of people. This article discussed a small scale renewable energy system that could ensure that villages all over the world have access to radios, lights, refrigeration and other critical technologies. The article also noted the potential implications in terms of health, education and the general standard of living for millions of people. The basic model involves setting up small solar panels in a good location in a village or on a farm. The panels can be used to charge up equipment that is either on-site or portable. This article described how to achieve economies of scale through mass production of many similar units. The project has been tested in Brazil and a donation to the project of $100,000 will be used to install a solar-powered public infrastructure comprised of water pumping, school and an Internet station. The funds will also be used to provide 70 solar lanterns for children living in two villages on the Rio Tapajos, a tributary to the Amazon near Santarem. 1 fig.

  7. Design and testing of small scale fish meat bone separator useful for fish processing.

    Science.gov (United States)

    Ali Muhammed, M; Manjunatha, N; Murthy, K Venkatesh; Bhaskar, N

    2015-06-01

    The present study relates to the food processing machinery and, more specifically machine for producing boneless comminuted meat from raw fish fillet. This machine is of belt and drum type meat bone separator designed for small scale fish processing in a continuous mode. The basic principal involved in this machine is compression force. The electric geared motor consists of 1HP and the conveyor belt has a linear velocity of 19 to 22 m min(-1), which was sufficient to debone the fish effectively. During the meat bone separation trials an efficiency up to 75 % on dressed fish weight basis was observed and with a capacity to separate 70 kg h(-1) of meat from fish at the machine speed of 25 rpm. During the trials, it was demonstrated that there was no significant change in the proximate composition of comminuted fish meat when compared to unprocessed fish meat. This design has a greater emphasis on hygiene, provision for cleaning-in-place (CIP) and gives cost effective need and reliability for small scale industries to produce fish meat in turn used for their value added products.

  8. Wind energy potential in Chile: Assessment of a small scale wind farm for residential clients

    International Nuclear Information System (INIS)

    Becerra, Miguel; Morán, José; Jerez, Alejandro; Cepeda, Francisco; Valenzuela, Miguel

    2017-01-01

    Highlights: • An assessment of a small scale wind farm was carried out. • Two Chilean locations were selected, which are geographically dissimilar. • The software tool selected for the project’s evaluation was HOMER. • All the project’s financial evaluations were negative. • Government policy tools and their applications were discussed. - Abstract: This work presents a techno-financial evaluation of two Chilean locations with promising wind potential: Laguna Verde placed in the central region of the country, and Porvenir in the southern region. A small scale wind farm was studied, considering a nominal electrical production capacity of 90 kW. This facility is comprised of three wind turbine models, all available in the national market. Currently, the tariff method used in Chile is the net billing scheme, where the energy bought and sold to the grid has different prices. The study is based on 300 hypothetical residential households. The software tool used to perform the assessment was the Hybrid Optimization of Multiple Energy Resources (HOMER). For all the scenarios the results showed a Net Present Cost (NPC), instead of a financial profit from the proposed projects. A sensitivity analysis was also carried out. From the group of variables studied, the NPC exhibited itself as more sensitive to the price of buying energy from the grid and to the annual average wind speed. Finally, a few government policies and their applications are discussed.

  9. Assessment of good manufacturing practice for small scale food industry in Malang region, East Java, Indonesia

    Science.gov (United States)

    Purwantiningrum, I.; Widyhastuty, W.; Christian, J.; Sari, N.

    2018-03-01

    Enhancing food safety in developing countries, such as Indonesia, poses more challenges, especially those of the small- and medium-scale. Various food safety systems are available and readily implemented in the food industry. However, to ensure the effectiveness of such systems, pre-requisite programs should be applied prior to the implementation of food safety system. One of the most acknowledged pre-requisite program is Good Manufacturing Practices (GMP). The aim of this study is to assess the GMP compliance of some small-scale food companies in East Java. Three types of traditional food product were selected, include tempe chips, palm sugar, and instant herbal drink. A survey involving three companies for each type of traditional food was conducted. Data was obtained through observation and assessment based on tabulated criteria in GMP criteria. In essential, the result revealed the compliment level of the food companies being surveyed. There was different level of compliment between each type of the food industry, where the palm sugar industry had the lowest level of compliment compared to the other two. This difference is due to the food safety awareness, social and cultural influences, and also knowledge on food safety and hygiene practice.

  10. Optimum operation of a small power production facility

    Energy Technology Data Exchange (ETDEWEB)

    Capehart, B.L.; Mahoney, J.F.; Sivazlian, B.D.

    1983-09-01

    To help reduce the U.S.A.'s dependence on imported oil for electrical power generation, the 1978 National Energy Act established regulations to promote construction and operation of cogeneration and small power production facilities. Many of these facilities are presently under construction, with a great number planned. This paper examines the operation of a small power production facility with on-site generation and storage, on-site use, and connection to an electric utility grid system for the purpose of both selling excess power and buying power. It is assumed that the buying and selling price of electricity varies frequently during the day and that the relevant price and demand data may be accurately projected into the near future. With this system description, a mathematical model is formulated and solved by linear programming to obtain a series of periodic buy and sell decisions so as to maximize the profit from operating the small power production facility. Results are presented to illustrate the methodology for determining potential profits.

  11. Antibiotic Resistance in Animal and Environmental Samples Associated with Small-Scale Poultry Farming in Northwestern Ecuador.

    Science.gov (United States)

    Braykov, Nikolay P; Eisenberg, Joseph N S; Grossman, Marissa; Zhang, Lixin; Vasco, Karla; Cevallos, William; Muñoz, Diana; Acevedo, Andrés; Moser, Kara A; Marrs, Carl F; Foxman, Betsy; Trostle, James; Trueba, Gabriel; Levy, Karen

    2016-01-01

    The effects of animal agriculture on the spread of antibiotic resistance (AR) are cross-cutting and thus require a multidisciplinary perspective. Here we use ecological, epidemiological, and ethnographic methods to examine populations of Escherichia coli circulating in the production poultry farming environment versus the domestic environment in rural Ecuador, where small-scale poultry production employing nontherapeutic antibiotics is increasingly common. We sampled 262 "production birds" (commercially raised broiler chickens and laying hens) and 455 "household birds" (raised for domestic use) and household and coop environmental samples from 17 villages between 2010 and 2013. We analyzed data on zones of inhibition from Kirby-Bauer tests, rather than established clinical breakpoints for AR, to distinguish between populations of organisms. We saw significantly higher levels of AR in bacteria from production versus household birds; resistance to either amoxicillin-clavulanate, cephalothin, cefotaxime, and gentamicin was found in 52.8% of production bird isolates and 16% of household ones. A strain jointly resistant to the 4 drugs was exclusive to a subset of isolates from production birds (7.6%) and coop surfaces (6.5%) and was associated with a particular purchase site. The prevalence of AR in production birds declined with bird age (P resistance (AR) in E. coli isolates from small-scale poultry production environments versus domestic environments in rural Ecuador, where such backyard poultry operations have become established over the past decade. Our previous research in the region suggests that introduction of AR bacteria through travel and commerce may be an important source of AR in villages of this region. This report extends the prior analysis by examining small-scale production chicken farming as a potential source of resistant strains. Our results suggest that AR strains associated with poultry production likely originate from sources outside the study

  12. Micro-scale energy valorization of grape marcs in winery production plants

    Energy Technology Data Exchange (ETDEWEB)

    Fabbri, Andrea; Bonifazi, Giuseppe; Serranti, Silvia, E-mail: silvia.serranti@uniroma1.it

    2015-02-15

    Highlights: • BioMethane Potential of grape marcs was investigated. • Grape marcs were characterized to realize a micro-scale energy recovery. • Comparative BMP batch-tests utilizing lab-scale reactors were performed. • Biogas valorization by grape marcs anaerobic digestion at small scale is evaluated. - Abstract: The BiochemicalMethanePotential (BMP) of winery organic waste, with reference to two Italian red and white grapes (i.e. Nero Buono and Greco) by-products was investigated. The study was carried out to verify the possibility to reduce the production impact in a green-waste-management-chain-perspective. The possibility to efficiently utilize wine-related-by-products for energy production at a micro-scale (i.e. small-medium scale winery production plant) was also verified. Results showed as a good correlation can be established between the percentage of COD removal and the biogas production, as the winery can produce, from its waste methanization, about 7800 kW h year{sup −1} electrical and 8900 kW h year{sup −1} thermal. A critical evaluation was performed about the possibility to utilize the proposed approach to realize an optimal biomass waste management and an energetic valorization in a local-energy-production-perspective.

  13. Micro-scale energy valorization of grape marcs in winery production plants

    International Nuclear Information System (INIS)

    Fabbri, Andrea; Bonifazi, Giuseppe; Serranti, Silvia

    2015-01-01

    Highlights: • BioMethane Potential of grape marcs was investigated. • Grape marcs were characterized to realize a micro-scale energy recovery. • Comparative BMP batch-tests utilizing lab-scale reactors were performed. • Biogas valorization by grape marcs anaerobic digestion at small scale is evaluated. - Abstract: The BiochemicalMethanePotential (BMP) of winery organic waste, with reference to two Italian red and white grapes (i.e. Nero Buono and Greco) by-products was investigated. The study was carried out to verify the possibility to reduce the production impact in a green-waste-management-chain-perspective. The possibility to efficiently utilize wine-related-by-products for energy production at a micro-scale (i.e. small-medium scale winery production plant) was also verified. Results showed as a good correlation can be established between the percentage of COD removal and the biogas production, as the winery can produce, from its waste methanization, about 7800 kW h year −1 electrical and 8900 kW h year −1 thermal. A critical evaluation was performed about the possibility to utilize the proposed approach to realize an optimal biomass waste management and an energetic valorization in a local-energy-production-perspective

  14. Returns to Scale in the Production of Hospital Services

    Science.gov (United States)

    Berry, Ralph E.

    1967-01-01

    The primary purpose of this article is to investigate whether or not economies of scale exist in the production of hospital services. In previous studies the results have implied the existence of economies of scale, but the question has not been satisfactorily resolved. The factor most responsible for clouding the issue is the overwhelming prevalence of product differences in the outputs of hospitals. In this study a method which avoids the problem of product differentiation is developed. The analysis strongly supports the conclusion that hospital services are produced subject to economies of scale. PMID:6054380

  15. A computationally inexpensive CFD approach for small-scale biomass burners equipped with enhanced air staging

    International Nuclear Information System (INIS)

    Buchmayr, M.; Gruber, J.; Hargassner, M.; Hochenauer, C.

    2016-01-01

    Highlights: • Time efficient CFD model to predict biomass boiler performance. • Boundary conditions for numerical modeling are provided by measurements. • Tars in the product from primary combustion was considered. • Simulation results were validated by experiments on a real-scale reactor. • Very good accordance between experimental and simulation results. - Abstract: Computational Fluid Dynamics (CFD) is an upcoming technique for optimization and as a part of the design process of biomass combustion systems. An accurate simulation of biomass combustion can only be provided with high computational effort so far. This work presents an accurate, time efficient CFD approach for small-scale biomass combustion systems equipped with enhanced air staging. The model can handle the high amount of biomass tars in the primary combustion product at very low primary air ratios. Gas-phase combustion in the freeboard was performed by the Steady Flamelet Model (SFM) together with a detailed heptane combustion mechanism. The advantage of the SFM is that complex combustion chemistry can be taken into account at low computational effort because only two additional transport equations have to be solved to describe the chemistry in the reacting flow. Boundary conditions for primary combustion product composition were obtained from the fuel bed by experiments. The fuel bed data were used as fuel inlet boundary condition for the gas-phase combustion model. The numerical and experimental investigations were performed for different operating conditions and varying wood-chip moisture on a special designed real-scale reactor. The numerical predictions were validated with experimental results and a very good agreement was found. With the presented approach accurate results can be provided within 24 h using a standard Central Processing Unit (CPU) consisting of six cores. Case studies e.g. for combustion geometry improvement can be realized effectively due to the short calculation

  16. Production hygiene and training influences on rural small-scale

    African Journals Online (AJOL)

    user

    Data analysis. Questionnaire data were coded using coding sheets. The coding sheets assigned numerical values to the answers, which had been captured on the spread sheets ... equipment was used as a proxy for hygiene practices. Farmers with ..... age as an indicator of life-cycle stage: the case for a farm family age ...

  17. Resource-use efficiency in maize production among small scale ...

    African Journals Online (AJOL)

    International Journal of Tropical Agriculture and Food Systems. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 2, No 2 (2008) >. Log in or Register to get access to full text downloads.

  18. Small scale production and storage quality of drymilled degermed ...

    African Journals Online (AJOL)

    One traditional soft cultivar was processed by the conventional method (direct grinding with disc mill) and was compared with flours obtained under various degerming and grinding intensities; two types of grinder (disc mill and hammer mill, already present on the market) were tested in parallel. Consumer satisfaction scores ...

  19. Thermal evolution and small scale structure of Sommerfeld enhanced dark matter

    International Nuclear Information System (INIS)

    Aarssen, Laura Gusta van den

    2013-04-01

    Although the existence of Dark Matter (DM) has been confirmed by many independent observations on various scales, its nature still remains a mystery. Leading candidates for the cold, non-baryonic DM are Weakly Interacting Massive Particles (WIMPs), that are well motivated from particle physics and naturally explain the observed relic density by their thermal production mechanism. In this thesis we focus on a particular class of WIMP models in which the Sommerfeld effect has to be taken into account. This is a quantum mechanical phenomenon that can significantly enhance the annihilation cross section in the non-relativistic limit. To describe the non-perturbative effect, we use a non-relativistic effective field theory derived from the full quantum field theory. We include a detailed discussion of the calculation for the righthanded sneutrino, which is the superpartner of the neutrino and a viable DM candidate. The Sommerfeld enhancement can have a profound influence on the thermal evolution of the DM, which can no longer be described by the standard scenario. We introduce a framework to correctly take this effect into account and apply it to a simple leptophilic DM model. A new era of annihilations can decrease the DM density even after usual freeze-out, and in some cases where the Sommerfeld enhancement is especially large, even continue until after matter-radiation equality. The effect on the asymptotic WIMP temperature, which can be directly related to a small scale cutoff in the matter density fluctuations, causes the mass of the smallest gravitationally bound objects to be larger than expected from standard calculations. Furthermore we study the effect of velocity dependent DM self-scattering in relation to the small scale structure formation. Numerical simulations of ΛCDM have shown a remarkable agreement with the large scale structure of the Universe. However, the simulations are in tension with observed abundances, inner densities and velocity profiles of

  20. Thermal evolution and small scale structure of Sommerfeld enhanced dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Aarssen, Laura Gusta van den

    2013-04-15

    Although the existence of Dark Matter (DM) has been confirmed by many independent observations on various scales, its nature still remains a mystery. Leading candidates for the cold, non-baryonic DM are Weakly Interacting Massive Particles (WIMPs), that are well motivated from particle physics and naturally explain the observed relic density by their thermal production mechanism. In this thesis we focus on a particular class of WIMP models in which the Sommerfeld effect has to be taken into account. This is a quantum mechanical phenomenon that can significantly enhance the annihilation cross section in the non-relativistic limit. To describe the non-perturbative effect, we use a non-relativistic effective field theory derived from the full quantum field theory. We include a detailed discussion of the calculation for the righthanded sneutrino, which is the superpartner of the neutrino and a viable DM candidate. The Sommerfeld enhancement can have a profound influence on the thermal evolution of the DM, which can no longer be described by the standard scenario. We introduce a framework to correctly take this effect into account and apply it to a simple leptophilic DM model. A new era of annihilations can decrease the DM density even after usual freeze-out, and in some cases where the Sommerfeld enhancement is especially large, even continue until after matter-radiation equality. The effect on the asymptotic WIMP temperature, which can be directly related to a small scale cutoff in the matter density fluctuations, causes the mass of the smallest gravitationally bound objects to be larger than expected from standard calculations. Furthermore we study the effect of velocity dependent DM self-scattering in relation to the small scale structure formation. Numerical simulations of {Lambda}CDM have shown a remarkable agreement with the large scale structure of the Universe. However, the simulations are in tension with observed abundances, inner densities and velocity