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Thai indigenous cattle production provided a sustainable alternative for the benefit of small-scale farmers, healthy food and the environment  

International Nuclear Information System (INIS)

[en] In Thailand, there were 5.66 million indigenous cattle and 1.76 million of their crosses. Farmers raised these cattle integrated with crop and fish in livestock-crop-fish integrated farming systems. These farming systems are in small scales for efficient utilization of available resources and for maximisation of production of diversified products per unit area to increase the income of the farmers and enhance food production. Thai indigenous cattle meat have more specific nutrient that are beneficial for consumers, such as omega 3, omega 6, and CLA. Furthermore, farmers use cattle manures as fertilizer for crop production, production of plankton for the fish and biogas/electric power used in the household. Additionally, Thai indigenous cattle are used for draught power. Consequently, Thai indigenous cattle increased food production and there was minimal cattle waste on farms thus, we could keep the environment clean and green. Performance data, meat quality, compost production, biogas production, and draught animal and reference were collected from 103 smallholder farmers in the northern part of Thailand, northeastern, central and southern parts of Thailand during October 2005 to September 2007. Growth and reproductive performance: Thai indigenous cattle had various skin and hair colour such as red, light brown, black, piebald, and only Kow-Lamphun cattle in northern part of Thailand, orange-pink skin and white hair colour. Their navels were not slackened but attached to the belly. Their dewlaps were also not slacken. The average birth weight was 19.6 kg and the weaning weight at 200 d of age was 137.96 kg. They had good characteristics of heat tolerance, disease resistance, and high fertility traits. They were the main red-meat source for consumers. Thai indigenous cattle were main source of red meat for consumption in Thailand. They produced high Omega 3 and Omega 6 in red meat, so their meat was the main source of protein and healthy food.Other utility of Thai indigenous cattle integrated farming system: Farmer raised on average 31.95 heads of Thai indigenous cattle on each farm integrated with crops (rice, corn, pineapple, sugar cane) and fish (striped catfish, catfish, tilapia, crucian carp). Cattle were fed on natural grass, rice straw as the main feed and other by-product from crops. Farmers used cattle manure to replaced chemical fertilizer and produced compost, which was used as fertilizer for crop production. Farmers also used manure to produce plankton for fish. They harvested 85.19 ton of crop production by using compost from manure and produced 0.25 ton per rai, which was less than the average country production (0.40 ton/rai). Average fish production was 100.00 kg per farm per year (147.06 kg/rai), which was similar to fish feeding with manure and concentrate (142.67 kg/rai). By integrating production in livestock-crop-fish, farming systems on small-scale, farmers produced safety food and gain their income. In addition, they could prevent air pollution, and global warming, leading to clean environment. (author)

2009-01-01

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Economic Efficiency of Small Scale Farmers in Ogun State, Nigeria  

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Full Text Available Cassava holds a prominent position as a food and industrial crop in the Nigerian economy. Thus, there are government initiatives to support its mass production for domestic use and export. This study investigated the efficiencies of cassava production in Odeda Local Government of Ogun State. A random sample of 200 cassava producers was taken and subjected to budgetary and stochastic frontier analyses. Results indicated that most of the farmers were male (90%) with more than half (53%) above 50 years of age. Land holding by inheritance (78%) was prevalent. The gross margin and profit were N105, 775 and N95. 738,10 respectively. Cost ratio (1.8) and percentage profit (80%) indicated that cassava farming was profitable in the area. Total variable and labour costs were 91.6% and 68.2% of the total cost respectively. The return to scale was 1.024. Farm size (0.771) and quantity of planting stakes (0.203) significantly (p ? 0.01) affected cassava production. Age and farming experience contributed to technical inefficiency while cost of fertilizer, cost of herbicides, membership of cooperative and level of education enhanced technical efficiency. Efficiency of cassava growers ranged between 88.69 and 100 with a mean of 89.4. It was concluded that cassava production was highly profitable in the area and farmers operated with maximum efficiency given the current technology. Farmers were advised to reduce labour costs and thus increase profit margin.

Adeyemo, R.; Oke, JTO.; Akinola, AA.

2010-01-01

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Effect of a Food Crop Development Project on Livelihood of Small-Scale Maize Farmers, Ghana  

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Full Text Available The Food Crop Development Project (FCDP) was introduced with the aim of improving farm incomes, household food security, nutrition and reducing poverty among small-scale farmers. This study sought to find answers to the questions of whether the project improved farmers’ access to credit, improved maize output or whether small-scale maize farmers adopted the improved maize production practices and how it impacted on maize production. Descriptive survey was conducted and using multi-stage random sampling procedure a final sample of 130 farmers was selected. The results indicated that participation in FCDP had a positive and significant but moderate relationship with maize output. More participants reported having easy access to credit than nonparticipants with chi-square value of 17.29 being highly significant indicating the possible relationship between ease of access to credit and participation in FCDP. The OLS stepwise regression analysis showed that participation, farm size and ease of access to credit were the main predictors of maize output while participation, income and household size were also the main predictors of food security. Thus, FCDP helped to improve the livelihoods of maize farmers in the study area. The policy implication of these findings is that subsidized agricultural input projects like the FCDP, have the potential to improve food security and farm incomes of peasant households.

Julio César Vinay-Vadillo; José Alfredo Villagómez-Cortés; María Rebeca Acosta-Rodríguez; Clément Rocher

2012-01-01

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Worth assessment of information and their access points by small scale cassava farmers in Nigeria  

Scientific Electronic Library Online (English)

Full Text Available Abstract in english This study determined the access, worth assessment and use of information by small-scale farmers in Oyo State. The study described socio-economic characteristics of small-scale cassava farmers; ascertained information access point preferences and analyzed information worth assessment. A multi stage sampling was used to select 360 respondents and data were collected through pre-tested and face validated questionnaire with a reliability coefficient of 0.88. The results show (more) that majority of the cassava farmers (76.4%) had low access to information and 85.6% rated cassava innovation packages as of low worth. The most frequently used access point is oral communication (83%), which was also rated highest in motivation ability (77.7%), regularity (96.3%) and relevance of information (83.4%). Radio was rated as the most persistent (68.5%). social participation, farm size and use of hired labour had a statistically significant effect on access to information (p

Osikabor, B.; Oladele, I. O.; Ogunlade, I

2011-01-01

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Diversity of shifting cultivation cycles among small-scale farmers in Peruvian Amazon  

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Full Text Available Although shifting cultivation is practiced by millions of farmers, it is often blamed for caus-ing deforestation and keeping farmers in pov-erty. Our study focused on the Amazon basin, where small-scale farmers widely practice shift- ing cultivation. The objective was to identify the diversity in land use after initial slash-and- burn land clearing among migrant peasants. Our research aimed at documenting typical crop sequences, plant species composition and specific lengths of particular phases of shifting cultivation cycles on the basis of farmers re-lated field histories. Land use was examined in two settlements: Antonio Raimondi and Pimen-tal in Ucayali region, Peru. Data was gathered via semi-structured questionnaires that focused on the socio-demographic characterization of agriculture-dependent households and their land use characteristics. More in-depth as-sessments of crop occurrence, cropping se-quence and length of the different shifting cul-tivation cycles were conducted on 114 fields in Pimental and 44 fields in Antonio Raimondi. In-terview analysis showed that in both villages, forest cover has substantially decreased over the last 10 years. Results also indicate consid-erable variation in swidden-fallow systems. Whereas settlers in Antonio Raimondi plant annual crops after slashing and burning the forest, settlers in Pimental gave more impor-tance to perennial crops. Progress in deforesta-tion and land degradation is relatively more pronounced in the younger settlement (Antonio Raimondi). These differences are likely caused by the different social backgrounds of settlers and histories of each site. Small-scale farmers in the study area are now facing a problem with the transition from shifting cultivation to sed-entary farming. Farmers in areas with a preva-lence of annual cropping use a significantly shorter fallow period, which causes a higher rate of forest degradation. As annual cropping seems to be unsustainable in relation with for-est degradation, farmers should either use a longer natural fallow to sustain longer cropping cycles, or shift to tree-based land use systems.

Bohdan Lojka; Jan Banout; Lucie Banoutova; Vladimir Verner; Patrick Van Damme

2011-01-01

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Effect of Poultry Production on the Poverty Status of Small Scale Farmers in Oyo State, Nigeria  

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Full Text Available Using data from 104 small scale poultry farmers in Oyo state of Nigeria, this study examined the role of poultry production in rural poverty reduction. The results show that majority of the farmers were male (87 percent), married (87 percent), having family size of 5 to 7 persons (53 percent), above 44 years of age with farming experience of 7.5 years on average and with formal education (95 percent). The average net farm income (NFI) is N788,164 per annum indicating that, the business is worth investing in. Poverty incidence, poverty depth, and severity of poverty are 49 percent, 23 percent and 13 percent respectively, the poor farmers need to generate an additional 23 percent of the fixed amount of income to cross the threshold of poverty. The result showed that male headed households and farmers without tertiary education are poorer. Poultry income and education level of the household head have significant, negative effects on poverty status of the households indicating that, additional increase in these variables will reduce the probability of being poor.

Babatunde, Raphael Olanrewaju; Adekunle, Adedayo Olufemi; Olagunju, Funke Iyabo

2012-01-01

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Multinomial Logit Analysis of Small-Scale Farmers’ Choice of Organic Soil Management Practices in Bungoma County, Kenya  

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Full Text Available Bungoma County is one of the areas in Kenya where maize is produced on small-scale basis; however, the County isfacing soil nutrient depletion due to continuous and unsustainable cultivation of land. Various interventions have sensitized farmers into adopting organic soil management techniques of enhancing soil fertility and upholding environmental sustainability. The study was aimedatestablishing the most preferred organic soil managementtechniques among farmers and the factors influencing the choice of these techniques. This wasbased on an exploratory study of small-scale organic maize farmers in Bungoma County.Asimple random sampling approach was used to select a sample of 150 smallholder maize farmers and primary data was collected using a semistructured questionnaire. In the analyses, descriptive statistics and a multinomial Logit model were employed using STATA computer program. The results indicated that extension, farm size household size, gender, age, education, credit, group membership, land tenure, farm distance and slope of land significantly influenced the choice of different techniques. Therefore the study recommends that policies in support of organic soil management should disaggregate farmers according to their socioeconomic, farmer and farm characteristics in order to achieve their intended objectives. Further there is need to increase extension visits to improve farmer awareness on the advantages of the various techniques.

Oscar I. Ayuya; Waluse S. Kenneth; Gido O. Eric

2012-01-01

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A Survey of Mechanization Problems of the Small Scale (Peasant) Farmers in the Middle Belt of Nigeria  

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Full Text Available Food shortage problem is increasing every day among the developing nations. So many farmers are on the land on small scale basis and their production has not been enough. Their farm sizes have not increased over the years due to absence of the relevant mechanization machinery. This study was made to evaluate the level of solutions of the problems of small farm mechanization, which is the only viable means of food production in the developing nations such as Nigeria. From the studies, the various levels of mechanization tools in the various farm operations are as follows: land clearing 21.54%, tillage 24.62%, planting 3.85%, spraying 86.15%, fertilization 2.13%, weeding 3.08%, harvesting 40%, crop processing 7.69% and crop storage 0.00%. Most of the farm sizes (93.85%) range from 1-5 hectares. The mechanization process being emphasized in the country is still beyond the scope of the small scale farmers who produce the bulk of the food. It is recommended among other things that government should set up agricultural machinery industries which should developed or purchase and hired out to small scale farmers at subsidized rates to increase the level of mechanization of certain farm operations in the middle belt states of the country.

Jonathan Kuje Yohanna; Ango Usman Fulani; Williams Aka'ama

2011-01-01

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A Success Story of Organizing Small Scale Farmers in Kenya : It's Possible Replication for the Payment of Environmental Services?  

DEFF Research Database (Denmark)

Managing agricultural landscapes for reducing carbon dioxide emissions is believed to be a Payment for Environmental Services mechanism (PES) of major significance after the 2012 Kyoto Protocol era. The big number of small scale farmers in the developing countries, and not least in SSA, will through this have a chance to contribute to national development, but to also enhance their own livelihood. The big problem of relying on small scale farmers is an organization model that ensures endurance and reliability. The Kenya Tea Development Agency (KTDA) has through almost 50 years been successful in integrating 600.000 smallholders in the tea production making tea number one income earner in Kenya and enhancing the livelihoods of the involved contract growers. The article argues that lessons should be learned from the success of KTDA in possibly replicating the organizational model to other crops, 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 trade.

Buch-Hansen, Mogens

2012-01-01

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The Right to Food Sovereignty for Small Scale Farmers: Case Study of Farming Cooperatives in Limpopo Province, South Africa  

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Full Text Available This paper on small scale farmers focuses on the right to food sovereignty in South Africa. Food sovereignty is defined as the fundamental democratic right to shape agricultural and food policy from the bottom up. Africa is the hardest hit by climate change because it depends on natural resources where small-scale agriculture is the dominant method of food production, except in South Africa where commercial agriculture dominates. This has direct links to climate change discourse reveals that rapid climate change including more frequent and intense weather systems with greater climate variability and the effects of increases in the average global temperature lead to changes in average rainfall patterns (Babagura 2011). In Sub-Saharan Africa, men make up approximately 85% of landholders and women 15% (UN Africa HDR 2012). Cultural practices and the dominance of patriarchal norms influence equal ownership and inheritance rights for men and women. Consequently landownership amongst women is lower in sub-Saharan Africa than in any other region in the world. In contrast, women make up approximately 50% of the agriculture workforce on male owned African small scale farms. Therefore, women in sub-Saharan Africa have less control than men do over productive resources such as assets of land and credit. Women’s time is often devoted to the domestic sphere in activities that are non-marketed and undervalued and their access to key institutions such as markets is curtailed (Annecke 2010). Climate change discourse demonstrates that the poor are disproportionately affected especially women who become shock absorbers during a food crisis, skipping meals to ensure family members have adequate nutrition. Household food security is part of a complex matrix of inequality which includes high levels of unemployment and increasing impoverishment because of the rising cost of basic services of electricity and water. Consequently, the increasing prices of basic foods like maize and wheat as the staple foods of most rural and urban poor poses a problem, because impoverished households are not buyers of food. Coupled with the stressors of poverty, poor health (HIV and AIDS) and societal inequalities (race and gender) small scale farmers have less flexibility to protect themselves or avoid risks. This case study based on group interviews with small scale farmers who are members of cooperatives located in the Mopani District in the Limpopo Province in South Africa investigates how these small scale farmers have addressed food insecurity.

Sharon Groenmeyer

2013-01-01

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Analysis of the use of credit facilities by small-scale fish farmers in Kenya  

UK PubMed Central (United Kingdom)

The government of Kenya encourages aquaculture development by offering credit facilities through the government agricultural finance institution, Agriculture Finance Corporation. Nevertheless, the level of credit use in fish farming is very low. Access to credit is among several factors that affect farmers' decision of whether to use particular technology or services. The study examined factors that affected the decision of fish farmers in Kenya to utilize credit facilities in fish production using a probit model. The analysis suggests that farmers in the Western province will have a 19% more probability of using credit facilities for their fish farming operations than farmers from the other provinces such as the Rift Valley, Central, and the Eastern province. The effect of tilapia sales on the probability of credit use by fish farmers is more than three times that of catfish sales. Total pond acreage owned by fish farmers had a positive effect on credit use but the effect was very small and negligible. The level of fish farmers' use of credit facilities is very low, and there is probably the need to educate farmers on credit use and for the government agricultural lending agency and other commercial agricultural lenders to invest in this enterprise. Kenyan lending institutions have financed traditional agricultural enterprises, and with the growing production of farmed fish, more research is needed to document the aquaculture business model to assist in assessing the profitability potential in aquaculture.

Quagrainie KwamenaK; Ngugi CharlesC; Amisah Stephen

2010-04-01

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A Comparative Study of Marketing Problems Faced by Small-scale Crop Farmers in Botswana and Kenya. Is There a Way out?  

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Full Text Available Most governments in third world countries including sub Saharan Africa, tend to either neglect or fail to the avail the necessary resources to small-scale farmers to enable such farmers attain any meaningful development. The small-scale farmers contribute the biggest percentage of the national food requirement compared to large-scale farmers who produce largely for international markets. Besides, small-scale farmers contribute to the creation of employment, development of agro-based industries, improvement of social welfare and the contribution to economic advancement of most developing countries. The development of this sector depends mainly on the availability of ready markets particularly the development of the marketing mix using the original 4P`s of marketing. Any business aims at offering consumers needed products that are competitive, available, well packaged and distributed according to consumer preferences. Pricing, distribution and promotion issues should also be incorporated in order to boost sales of locally produced products in preference to imported goods. With proper management and marketing improvement in this sector, most African countries could increase food production and cease to be dependent on food relief aid from donors. A comparative study approach was used to compile this study comparing the problems of small-scale farmers in Botswana and Kenya. We made use of available secondary data form publications in the two countries. This study aimed at finding out whether marketing problems faced by small-scale farmers in Botswana also affect their Kenyan counterparts and suggest possible solutions.

P.T. Mburu; S.K. Massimo

2005-01-01

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Tick control by small-scale cattle farmers in the central Eastern Cape Province, South Africa  

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Full Text Available A survey conducted in 5 magisterial districts involving rapid rural appraisal and a questionnaire showed participation in state-managed and funded dipping programmes by cattle owners in communal areas of the central Eastern Cape to be nearly complete, with 98 % of livestock owners interviewed participating in all dipping events. Disease control was the main reason for participation, but farmers perceive dipping to have a much broader disease-preventing activity than is really the case. Other reasons for participation in dipping programmes were to prevent ticks from sucking blood, provide animals with a clean appearance, and prevent damage to teats of cows. Many livestock owners complement dipping with other tick control measures, including old motor oil, household disinfectant, pour-on acaricide and manual removal of ticks. Recently local farming communities were given the responsibility of buying dipping acaricide. This has presented them with the challenge of developing farmer-managed, cost-effective tick control programmes. At present, this process is constrained by lack of information and farmer training.

P.J. Masika; A. Sonandi; W. Van Averbeke

2012-01-01

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Effect of Irrigation on Poverty among Small-Scale Farmers in Limpopo Province of South Africa  

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Full Text Available Despite the strength and stability of South African economy, poverty and inequality remain a glaring and persistent issue in the country. About 40% of the population live in outright poverty or continuing vulnerability to being poor, with poverty being more persistent in rural areas. The Forster-Greer-Thorbecke index and a Logit econometric model were used to measure the dynamics of poverty among irrigation and non-irrigation individuals and households. The poverty incidence, depth and severity were found to be higher among non-irrigation household than among irrigation households. In term of poverty depth, it will cost R51.08 per capita to eliminate poverty among small-scale farm families that practice non-irrigated, while R48.00 per capita will be needed to eliminate poverty among small-scale irrigation families.There was significant correlation between income poverty and capability and deprivation poverty. This Implies that policies aimed at mitigating income poverty may also mitigate capability and deprivation poverty.

Majory Ongie Meliko; Stephen A. Oni

2011-01-01

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ANALYSIS OF PIG PROFILES ON SMALL-SCALE PIG FARMERS IN MANOKWARI-WEST PAPUA  

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Full Text Available This study was aimed to determine the profiles of pig farming systems. Participatory situation analysis was employed to gain data relating to pig profiles in the urban and rural areas of Manokwari. Due to the interests of combining many correlated data, multivariate analysis using Principal Component Analysis (PCA) was performed. Cluster Analysis using Agglomerative Hierarchical Clustering was applied for analysis of merge samples based on similarity in components’ composition across sites. There were various twelve classes of pig profiles in Manokwari. In principal component of the first axis correlation of several components shows strong positive relation e.g. in piglets, sows, and total herd size. Status of region in the first axis of PCA (P1) through which pigs were raised had negative correlation, including grower, household member and pig production. In the second axis (P2), negative correlations were shown in piglets, grower, boars, total herd size and the Pig Production Potential (PPP). Status of region has underpinned profiles of pigs. Several farmers were able to manage their farm continuity in a steady composition. Selling pigs was the main aim and few farmers play a role as pure breeder.

D. A. Iyai; B.W. I. Rahayu; I. Sumpe; D. Saragih

2011-01-01

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Hot Pepper Production and Marketing in Southwest Ethiopia: An Alternative Enterprise for Small Scale Farmers  

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Full Text Available This study was initiated with the objective of examining the existing hot pepper production and marketing, assess its socioeconomic role in the life of producers and other actors and point out the existing bottlenecks of production and marketing. Descriptive statistics, net benefit and margin analysis were employed to analyze the data. The result indicated that local varieties called marco (in Omo Nada) and kolesh (in Gojeb) are largely used by farmers and provide a yield ha-1 of 16.39 and 12.21 quintal, respectively through using fertilizer and spacing technology. The assessment of the market structure revealed that the largest volume (50%) of sale directly goes to the local consumers followed by the volume channeled to assemblers (28.5%) and retailers (21.5%). The margin analysis revealed that producers take the highest profit margin of 100 and 68.2% when the product is sold directly to the local consumers and retailers, respectively. But when hot pepper is channeled to Jima and Addis Ababa, producers get a profit margin of 53.3 and 42.8%, respectively making the respective total gross margin taken by the intermediaries to be 46.7 and 57.2 out of which the largest share is taken by the assemblers without having a significant value addition activity. Therefore, with the assumption that their possible linkage role can effectively be taken by the local wholesalers and retailers, banning of local assemblers from the market chain can be taken as one option for improving the efficiency of the chain. Low productivity, illegal act of actors in the chain, poor quality of product, low and fluctuating price, small and confined market place together with long market distance were found to be the major problems adversely influencing the production and marketing of hot pepper in the area.

Zekarias Shumeta

2012-01-01

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Survey of the Current Status of Weed Control and Herbicide Usage by the Small-Scale Commercial Vegetable Farmers in Kenya  

International Nuclear Information System (INIS)

Vegetable production in Kenya is a market that has grown very rapidly in the decade due to increased demand in the local and international markets. This has led to an increase in hectarerage planted to vegetable thus leading in labour shortage due urban migration of potential casual labourers especially the youth. This has resulted to inadequate labour for weed control especially at the critical period. The objectives of this study were to find out the problems encountered by farmers in their bid to control weeds and whether they considered weeds as their major problem. The survey was conducted in Kikuyu, Lari and Kinango divisions where intensive vegetable farming is done by small-scale farmers for commercial purposes. The farmers were randomly selected and interviews conducted in their farms, based on Participatory Rural Appraisal (PRA) method. The results obtained showed that the farmers who previously relied on manual labour for weed control were increasingly using herbicides for weed control. The adoption of herbicide technology by these small scale farmers was out of their own initiative, either due to labour shortage or because one had a special weed problem that had defied other methods of control.From the information obtained it was clear that locally generated data information on herbicide use by small-scale farmers is seriously lacking for most if not all vegetable crops

1999-01-01

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An analysis of the Mngcunube "hands-on” mentorship program for small-scale stock farmers in the Eastern Cape, South Africa  

Scientific Electronic Library Online (English)

Full Text Available Abstract in english The Elundini program included small-scale livestock farmers in the Eastern Cape, South Africa. The program's data analyses and the impact on farmers and the economy were evaluated. Since program inception, sheep mortality decreased from >20% to 3%. Lamb weaning rates were approximately one lamb for every two ewes (50%). Farmers' annual income increased from R650.00 to R20,956.00 (R1.00~ $0.15) with a total net gain of >R56 million for the region. Strict mentor management (more) principles and payment for services were fundamental to the program's success. The impact of the program was immediately apparent and farmers were willing to pay for mentorship and treatments, provided they experience the benefits.

Jordaan, A J

2012-01-01

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AN AGRI-FOOD SUPPLY CHAIN MODEL TO ENHANCE THE BUSINESS SKILLS OF SMALL-SCALE FARMERS USING CORPORATE SOCIAL RESPONSIBILITY  

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Full Text Available In general, small-scale vegetable farmers experience problems in improving the safety and quality of vegetables for supplying high-class consumers in modern retailers. Farmer Group and/or Cooperative (FGC) should be able to assist its members to meet the relevant provisions of modern retail on product specifications, delivery terms, and internal business requirements. This study proposed an agri-food supply chain (ASC) model that involves the corporate social responsibility (CSR) activities to enhance the business skills of the FGC as supplier of modern retailer. Multi-objective optimization programming is developed to determine the amount and timing of supply, level of farmers training skills, quality improvement target, and the CSR total cost. The results show that the proposed model can be used to determine the priority of programs in order to empower farmers' groups as modern retail suppliers.

Wahyudi Sutopo; Muh. Hisjam; Yuniaristanto

2012-01-01

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What Makes Small-Scale Farmers Participate in Financing Agricultural Research and Extension? Analysis of Three Case Studies from Benin  

Science.gov (United States)

This paper analyses the organizational, financial and technological incentives that service organizations used to motivate farmers to finance agricultural research and extension in Benin. Understanding the foundations and implications of these motivation systems is important for improving farmer financial participation in agricultural research and…

Moumouni, Ismail M.; Vodouhe, Simplice D.; Streiffeler, Friedhelm

2009-01-01

 
 
 
 
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Factors Influencing the Adoption of Agro-chemical Technology by Small-scale Farmers in Kwali Area Council of Abuja FCT, Nigeria  

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Full Text Available The study was conducted to determine factors influencing the adoption of agro-chemicals technology by small-scale farmers in Kwali area council, of the Federal Capital Territory Abuja, Nigeria. Structured interview schedule was used to collect data for the study. Ten respondents were randomly selected from each of the eight districts making the area council giving a total of eighty respondents. Statistical tools involving means, frequency and percentage were used to analyze the data. Ordinary least square linear regression was used to determine factors influencing the adoption of agro-chemicals technology in the study area. The results of the study revealed that gender, age, farm income, marital status and years of farming experience have positive influence on the adoption of agro-chemicals in the study area. Management of Abuja Agricultural Development Project should endeavour to encourage farmers to form strong coherent group such as cooperatives to control agro-chemicals prices supplied by input representatives.

Bello, M.; Ibrahim, H. I.; Salau, E. S.; Kaura, A. G.; Age, A. I.

2010-01-01

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Use of herbal remedies by small-scale farmers to treat livestock diseases in central Eastern Cape Province, South Africa  

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Full Text Available The use of herbal remedies by African farmers in the treatment of livestock diseases was investigated using a range of methods, including group interviews, structured interviews, semi-structured interviews and participant observation. The study was concerned mainly with the 'why' and 'how' of herbal remedy use among African livestock holders farming on communally-owned land in central Eastern Cape Province. We found that the use of herbal remedies was still widespread because these remedies were cheap, locally available and convenient to administer. Farmers also used herbal remedies because they did not have knowledge of conventional remedies or found these too expensive and therefore used herbal remedies as a last resort. Most of the farmers interviewed (73 %) had used some form of herbal remedy. A small number of farmers did not use herbal remedies at all. They rejected them because they had bad experiences in the past or because they considered the practice outdated and socially inferior. Often farmers used herbal remedies in combination with conventional ones, but a substantial number relied on herbal remedies only. Farmers obtained herbal remedies principally by preparing their own or by purchasing from herbalists. Different plant parts were used to prepare herbal remedies in the form of infusions, decoctions, powders, pastes, and juices from fresh plant material. Preparations were made from a single plant or from a range of plants. Application of a remedy was by different routes and methods, depending on the perceived cause of the disease condition. Topical applications were used for skin conditions, powders were rubbed into incisions, drenches were common in the treatment of systemic conditions, and drops to treat ears and eyes. We identified several aspects of herbal remedy utilisation that could be subject to improvement, which included the absence of standard dose regimes, the potential toxicity of certain compounds present in plants used, over-exploitation of the plant resource and a lack of interest by the youth to learn the art.

P.J. Masika; W. Van Averbeke; A. Sonandi

2012-01-01

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Assessing yield and efficiency implications of relying on parasitoids for control of cereal stemborers: The case of small-scale maize farmers in Kenya  

UK PubMed Central (United Kingdom)

As part of a region-wide classical biological control (BC) program, the exotic larval parasitoid Cotesia flavipes was released in coastal Kenya in 1993 for the control of the invasive crambid cereal stemborers Chilo partellus. A 2-year survey of small-scale maize farmers covering the 2004 and 2005 maize production seasons was carried out in the area to compare yields and production efficiency (i.e. the capacity to obtained maximum yields with least cost input combination between farmers) who applied chemical pesticides and those who did not, thus knowingly or unknowingly relying on BC. The role of pest and parasitoid, habitat management techniques and soil fertility measures in influencing maize production was also investigated. The results revealed that average yields and technical efficiency of maize producers ranged from 1 to 1.2ton/ha and 57.9-67.9%, respectively. Farmers could improve maize yields by up to 42% by improving production efficiency and optimal allocation of labor and use of inorganic fertilizers. Because of low average maize yields, the return to pest control was low. Farmers that had natural grassy habitats in the vicinity of maize fields, applied fertilizers or used chemical pesticides to control stemborers obtained equivalent yields. Future yield improvement efforts should promote biological control as part of a whole strategy package to improve maize yields.

Kipkoech AndersonKipruto; Mitho?fer Dagmar; Yabann WilsonK; Maritim HenryK; Schulthess Fritz

2008-10-01

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Control of invasive Liriomyza leafminer species and compliance with food safety standards by small scale snow pea farmers in Kenya  

UK PubMed Central (United Kingdom)

The Kenyan horticultural industry faces a new challenge following invasion by the quarantine Liriomyza leafminer species Liriomyza huidobrensis, Liriomyza sativae and Liriomyza trifolii which have recently become pests of economic importance. Controlling Liriomyza leafminers poses serious difficulties due to their biology and quarantine status. This paper examines farmers' awareness of the pests and difficulties faced in controlling them. (1) A questionnaire survey showed that snow pea farmers in Kenya rely mainly on pesticides for control of invasive Liriomyza leafminers; (2) Sixty five percent of respondents perceived pesticides to be ineffective; (3) As a result, 74% of respondents increased the frequency of pesticide applications, 61% increased dose rates and 58% used broad-spectrum insecticides to avert damage by the pests; (4) Snow pea farmers who signed contracts with exporters and whose production practices were monitored for compliance with Good Agricultural Practices (GlobalGAP) used fewer control strategies; (5) These findings imply that the pest status of Liriomyza leafminers is likely to increase and snow pea production will significantly decrease in Central areas of Kenya unless an integrated leafminer management strategy is developed and farmers educated on methods of identifying them in their early stages of attack and use appropriate chemicals and application methods.

Gitonga ZacharyMaina; Chabi-Olaye Adenirin; Mithöfer Dagmar; Okello JuliusJuma; Ritho CeciliaNyawira

2010-12-01

25

Fishing Farmers or Farming Fishers? Fishing Typology of Inland Small-Scale Fishing Households and Fisheries Management in Singkarak Lake, West Sumatra, Indonesia  

Science.gov (United States)

Technical and socio-economic characteristics are known to determine different types of fishers and their livelihood strategies. Faced with declining fish and water resources, small-scale fisheries engage into transformations in livelihood and fishing practices. The paper is an attempt to understand these changes and their socio-economic patterns, in the case of Singkarak Lake in West Sumatra, Indonesia. Based upon the hypothesis that riparian communities have diverse, complex yet structured and dynamic livelihood systems, the paper's main objective is to study, document and model the actual diversity in livelihood, practices and performance of inland small-scale fisheries along the Singkarak Lake, to picture how households are adapted to the situation, and propose an updated, workable model (typology) of those for policy. Principal component analysis and cluster analysis were used to develop a typology of fishing households. The results show that small-scale fishers can be classified into different types characterized by distinct livelihood strategies. Three household types are identified, namely "farming fishers" households (type I, 30 %), "fishing farmers" households (type II, 30 %), and "mainly fishers" households (type III, 40 %). There are significant differences among these groups in the number of boats owned, annual fishing income, agriculture income and farming experience. Type I consists of farming fishers, well equipped, with high fishing costs and income, yet with the lowest return on fishing assets. They are also landowners with farming income, showing the lowest return on land capital. Type II includes poor fishing farmers, landowners with higher farming income; they show the highest return on land asset. They have less fishing equipment, costs and income. Type III (mainly fishers) consists of poorer, younger fishers, with highest return on fishing assets and on fishing costs. They have little land, low farming income, and diversified livelihood sources. The nature of their livelihood strategies is discussed for each identified group. This helps to understand the complexity and diversity of small-scale fishers, particularly in the study area which is still poorly known. This paper concludes with policy implication and possible management initiatives for environmentally prudent policy aiming at improvement of fishers' livelihood.

Yuerlita; Perret, Sylvain Roger; Shivakoti, Ganesh P.

2013-07-01

26

Fishing farmers or farming fishers? Fishing typology of inland small-scale fishing households and fisheries management in singkarak lake, west sumatra, indonesia.  

UK PubMed Central (United Kingdom)

Technical and socio-economic characteristics are known to determine different types of fishers and their livelihood strategies. Faced with declining fish and water resources, small-scale fisheries engage into transformations in livelihood and fishing practices. The paper is an attempt to understand these changes and their socio-economic patterns, in the case of Singkarak Lake in West Sumatra, Indonesia. Based upon the hypothesis that riparian communities have diverse, complex yet structured and dynamic livelihood systems, the paper's main objective is to study, document and model the actual diversity in livelihood, practices and performance of inland small-scale fisheries along the Singkarak Lake, to picture how households are adapted to the situation, and propose an updated, workable model (typology) of those for policy. Principal component analysis and cluster analysis were used to develop a typology of fishing households. The results show that small-scale fishers can be classified into different types characterized by distinct livelihood strategies. Three household types are identified, namely "farming fishers" households (type I, 30 %), "fishing farmers" households (type II, 30 %), and "mainly fishers" households (type III, 40 %). There are significant differences among these groups in the number of boats owned, annual fishing income, agriculture income and farming experience. Type I consists of farming fishers, well equipped, with high fishing costs and income, yet with the lowest return on fishing assets. They are also landowners with farming income, showing the lowest return on land capital. Type II includes poor fishing farmers, landowners with higher farming income; they show the highest return on land asset. They have less fishing equipment, costs and income. Type III (mainly fishers) consists of poorer, younger fishers, with highest return on fishing assets and on fishing costs. They have little land, low farming income, and diversified livelihood sources. The nature of their livelihood strategies is discussed for each identified group. This helps to understand the complexity and diversity of small-scale fishers, particularly in the study area which is still poorly known. This paper concludes with policy implication and possible management initiatives for environmentally prudent policy aiming at improvement of fishers' livelihood.

Yuerlita; Perret SR; Shivakoti GP

2013-07-01

27

Helping small-scale farmers in the semi-arid tropics: Linking participatory research, traditional research and simulation modelling  

International Nuclear Information System (INIS)

[en] The aim was to link necessary research skills to increase the range of options available to resource-poor farmers in the study area. The research consisted of on-station research to evaluate and understand cropping-system options resulting from insertion of a legume crop into the sorghum and castor system, on-farm research whereby farmers evaluate cropping-system options that are of interest to them, use of 15N as a label to help understand the nitrogen (N) balance of the various options, and cropping-systems simulation to examine long-term climatic risks from possible options. Particular attention was placed on the option of sorghum/pigeon pea intercrops, and on quantifying the inputs of N from animal manure and by the pigeon-pea component. We were also interested in the process of linking on-station to on-farm research, and simulation modelling to the cropping system research. One important outcome was that different groups identified different problems and posed different questions. The problems identified and questions raised were examined by use of scenario analyses run for ten to thirty years which contrasted the existing practice with a range of alternative practices. The simulations were useful in guiding the design of on-farm experiments. Other likely outcomes are the setting of low-rate fertilizer recommendations specifically for the semi-arid tropics, the marketing of small packs of fertilizers, and increased use of manure resources for crop production. (author)

2005-01-01

28

Analysis of wood-energy production and consumption strategies among small-scale farmers in central Kenya  

Energy Technology Data Exchange (ETDEWEB)

This study focuses on wood-energy production and consumption strategies among small-scale farm households in central Kenya. The specific objective were: (1) to determine how households had responded to specific wood-energy policies; (2) to identify factors associated with household adoption or non-adoption of the strategies. Different programs aimed at addressing wood-energy shortages in Kenya were initiated or strengthened during the 1980s: fuelwood or multipurpose tree planting; development and dissemination of improved stoves and fireplaces; promotion of increased accessibility to wood-energy substitutes. Household adoption levels for policy-supported strategies have remained low despite promotion. Survey data from two villages in Nyeri district were collected to determine the factors associated with adoption of the Kenya Ceramic Jiko, the [open quotes]Kuni Mbili[close quotes] stove/fireplace, kerosene stoves, electric cookers, and fuelwood or multipurpose tree planting. Adoption rates varied from as low as 1 percent for electricity to 43 percent for the Kenya Ceramic Jiko. Important policy variables included extension visits per year, income levels, years of formal education received by head of household, access to different fuels, area of farm-land owned, household size, and locational characteristics of the villages. Policy recommendations included: use of research results to direct policy; improvement of information flows between policy makers, extension agents, and technology-users; increased support of agroforestry; and better program coordination. Recommendations for further research included: examining more areas where efficiency gains in energy production and consumption can be made, extending the study to cover the drier parts of central Kenya, and conducting regular case studies in order to better understand the adoption process over time.

Mwangi, A.M.

1992-01-01

29

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).  

UK PubMed Central (United Kingdom)

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 <1,000 MPN per 100 mL irrigation water and <1,000 MPN per g of compost. The vegetables produced by Agri-Hub small-scale farmers met the requirements for total coliforms of <200/g set by the South African Department of Health at the time of sampling. E. coli MPN values for irrigation water and 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.

Mdluli F; Thamaga-Chitja J; Schmidt S

2013-01-01

30

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)  

Directory of Open Access Journals (Sweden)

Full Text Available 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 <1,000 MPN per 100 mL irrigation water and <1,000 MPN per g of compost. The vegetables produced by Agri-Hub small-scale farmers met the requirements for total coliforms of <200/g set by the South African Department of Health at the time of sampling. E. coli MPN values for irrigation water and 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.

Fezile Mdluli; Joyce Thamaga-Chitja; Stefan Schmidt

2013-01-01

31

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)

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 MPN per 100 mL irrigation water and MPN per g of compost. The vegetables produced by Agri-Hub small-scale farmers met the requirements for total coliforms of MPN values for irrigation water and 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

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

2013-09-13

32

Conceptions of healthy eating among ecological farmers in Parana, Southern Brazil.  

UK PubMed Central (United Kingdom)

OBJECTIVE: To describe ecological farmers' conceptions of healthy eating. METHODS: Study with a qualitative approach. In January and February 2007, supported by a guide, in-depth interviews were conducted with 11 women and one man who were living in an agricultural community in Rio Branco do Sul, Southern Brazil. The interviewees were selected randomly from among the 20 ecological farming families in this municipality. RESULTS: Three analysis categories were identified: "awareness of healthy eating"; "purchasing power" and "healthy land". The significance of healthy eating for the female farmers involved the idea that foods should be natural, without agricultural pesticides or manufactured chemical products. The daily routine should include abundant consumption of fruits, greens and other vegetables, in addition to the basic rice, beans and meat, and the composition of dishes should aim towards prevention of obesity and chronic-degenerative diseases. Care regarding natural resources in order to ensure production of healthy foods, food safety, environmental sustainability and the future of life on the planet form part of the concept of healthy eating. CONCLUSIONS: Knowledge, self-criticism and discernment accompanied the conceptions of healthy eating.

Ell E; Silva DO; Nazareno ER; Brandenburg A

2012-04-01

33

Small scale optics  

CERN Multimedia

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

Yupapin, Preecha

2013-01-01

34

Current Scenario of the Small-scale Broiler Farming in Bangladesh: Potentials for the Future Projection  

Directory of Open Access Journals (Sweden)

Full Text Available In Bangladesh, there are two types of broiler farming of which contract broiler farming is still under trial while independent small-scale broiler farming is dominant and performed for the development of broiler sector. The present study examined the potentials of small-scale independent broiler farms and farmers’ economic behavior in relation to farm size. Farm size is found to be closely related to farmers’ behavior and attitude. Farmers’ behavior and attitude appeared to be very crucial factor for the development of broiler production. The primary data were collected from the independent small-scale farms in Mymensingh district of Bangladesh. The results showed that independent small-scale broiler farming is a profitable venture for rural farmers. Farmers are involving in this sector because of lower investment, less space requirement, utilization of family labor and quick returns. To examine the farmers’ behavior, farmers were classified into two income goal groups in terms of total per capita income: a) First Income Goal Group (FIGG) and b) Second Income Goal Group (SIGG). The economic behaviors of the farmers were differed by income goal groups. Most of the farmers belonging to the FIGG were interested to enlarge their farm size, the opposed trend has been observed in farmers of SIGG. Economic behavior and attitude should be considered in making any suggestion and recommendation for changing the existing level of small-scale broiler farming.

Md. Saiful Islam; Sasaki Takashi; Kaniz Quamrun Nahar Chhabi

2010-01-01

35

Jatropha and Sustainable Livelihood of Small-scale Farmers  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The jatropha trees oil containing seeds can be used for biofuel. There are a lot of discussions about whether a Jatropha production and utility can be beneficial for a sustainable development in the developing countries, or if it’s just another cash crop for oil-export to the developed countries bio...

Ladefoged, Tanja, Helle Momsen Fredslund; Hansen, Rasmus bo, Tilde Anker Worsøe

36

Small Scale Thermosyphon Heat Exchanger.  

Science.gov (United States)

A small circular heat transfer cell was used to study the cooling of a disc heat source by a thin evaporating liquid film. This small scale thermosyphon is a thermal spreader and a passive heat sink in that the interfacially induced liquid flow rates are ...

M. Sujanani E. W. Kiewra P. C. Wayner

1986-01-01

37

Small-scale-field Dynamo  

CERN Multimedia

Generation of magnetic field energy, without mean field generation, is studied. Isotropic mirror-symmetric turbulence of a conducting fluid amplifies the energy of small-scale magnetic perturbations if the magnetic Reynolds number is high, and the dimensionality of space d satisfies 2.103 < d <8.765. The result does not depend on the model of turbulence, incompressibility and isotropy being the only requirements.

Gruzinov, A V; Sudan, R N

1996-01-01

38

Small scale helium liquefaction systems  

International Nuclear Information System (INIS)

We have developed two small-scale helium liquefaction systems that provide solutions for liquid helium usage in laboratories. These helium liquefaction systems use two-stage pulse tube cryocoolers to provide cooling at 4 K. The cold head/liquefier resides inside of the neck of a dewar. The room temperature helium gas to be liquefied enters the neck of the dewar and is efficiently pre-cooled down to 5-6 K by means of the regenerators and pulse tubes of the cold head before being liquefied. Two models of liquefaction system, LHeP12 and LHeP18, produce liquid helium from room temperature gas with the rates of >12 L/day and 18 L/day.

2009-02-01

39

Are Small-Scale Irrigators Water Use Efficient? Evidence from Lake Naivasha Basin, Kenya.  

UK PubMed Central (United Kingdom)

With increasing water scarcity and competing uses and users, water use efficiency is becoming increasingly important in many parts of developing countries. The lake Naivasha basin has an array of different water users and uses ranging from large scale export market agriculture, urban domestic water users to small holder farmers. The small scale farmers are located in the upper catchment areas and form the bulk of the users in terms of area and population. This study used farm household data to explore the overall technical efficiency, irrigation water use efficiency and establish the factors influencing water use efficiency among small scale farmers in the Lake Naivasha basin in Kenya. Data envelopment analysis, general algebraic and modeling system, and Tobit regression methods were used in analyzing cross sectional data from a sample of 201 small scale irrigation farmers in the lake Naivasha basin. The results showed that on average, the farmers achieved only 63 % technical efficiency and 31 % water use efficiency. This revealed that substantial inefficiencies occurred in farming operations among the sampled farmers. To improve water use efficiency, the study recommends that more emphasis be put on orienting farmers toward appropriate choice of irrigation technologies, appropriate choice of crop combinations in their farms, and the attainment of desirable levels of farm fragmentation.

Njiraini GW; Guthiga PM

2013-08-01

40

Cogeneration: small scale, big gains  

Energy Technology Data Exchange (ETDEWEB)

Despite its technological history throughout this century in the chemical, petroleum refining, food, metals and mining, and other industries, cogeneration has only recently become economically attractive to a number of users. Rapid energy cost increases during the '70s, coupled with encouraging legislation and court rulings, have spurred development of new, more efficient systems in a wide range of output ratings. Thus, cogeneration has become a feasible alternative for both new and retrofit projects. Until last year, though, only largescale, custom-engineered cogeneration equipment was available on a widespread basis. For smaller users, the initial cost and sheer physical size of such equipment makes them uneconomical and impractical for normal operation. During the past year, however, more manufacturers began offering smallscale pre-packaged cogeneration systems in the 60- to 150-kw range, as well as new financing plans for those systems. A major incentive for the use of cogeneration among smaller users is that they must pay more for utility-supplied electricity, receiving none of the discounts given larger users. As a result, small-scale cogeneration equipment is becoming more familiar in Commercial-IndustrialInstitutional (CII) environments and in schools. Examples are given and discussed in detail.

Green, L.

1984-07-01

 
 
 
 
41

Small scale pelletizing equipment for agriculture; Smaaskalig pelleteringsanlaeggning foer lantbruket  

Energy Technology Data Exchange (ETDEWEB)

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 pelleting plants to be economically viable, cheap raw materials or good prices for the final product (pellets) is necessary. The agricultural raw material that is currently considered to have the best economic potential for small-scale processing is straw (for bedding pellets). Since the plant is suitable for mobile use, it can be used for several purposes, for example production of bedding pellets in the autumn and fuel pellets in the spring and summer

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

2009-06-15

42

Handbook for small scale fuelwood chipping operations  

Energy Technology Data Exchange (ETDEWEB)

The handbook was produced by the activity 1.2 - Harvesting of Task XII/IEA Bioenergy. The objective is to assemble and synthesize information on efficient and safe methods for the production and handling of fuel chips from low-grade forest biomass in small-scale operations. A wide range of topics related to small-scale chipping is addressed. These include: the reasons that people produce and burn wood chips; good and bad qualities in wood chips; technical information on chipper types (emphasizing disc chippers), the adjustment and maintenance of chipper knives; different approaches to the supply of chipping wood; various places where chipping is normally done; guidelines for safe and efficient chipping; storage of wood chips; typical annual wood chips consumption on small farms; productivity in small-scale chipping operations; the cost components in small-scale chipping; and common errors in small-scale chipping operations. (18 refs)

McCallum, B. [Ensight Consulting, Prince Edward Island (Canada)

1997-12-31

43

Method and system for small scale pumping  

Energy Technology Data Exchange (ETDEWEB)

The present invention relates generally to the field of small scale pumping and, more specifically, to a method and system for very small scale pumping media through microtubes. One preferred embodiment of the invention generally comprises: method for small scale pumping, comprising the following steps: providing one or more media; providing one or more microtubes, the one or more tubes having a first end and a second end, wherein said first end of one or more tubes is in contact with the media; and creating surface waves on the tubes, wherein at least a portion of the media is pumped through the tube.

Insepov, Zeke (Darien, IL); Hassanein, Ahmed (Bolingbrook, IL)

2010-01-26

44

Biomass for energy - small scale technologies  

Energy Technology Data Exchange (ETDEWEB)

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

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

1997-12-31

45

Small scale structure on cosmic strings  

Energy Technology Data Exchange (ETDEWEB)

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.

Albrecht, A.

1989-10-30

46

Small scale structure on cosmic strings  

International Nuclear Information System (INIS)

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.

1989-01-01

47

A Comparative Study of Selected Small Scale Irrigation (SSI) Schemes in Akwa Ibom State, Nigeria (II)  

Directory of Open Access Journals (Sweden)

Full Text Available This study was conducted to determine what variations exist in the measured attributes of farmers from different selected SSI schemes. Mechanization survey data collected between October 2005 and March 2007 from 12 SSI schemes with the aid of structured interview were statistically compared. The result showed considerable degree for variations in the socio-economic, agronomic and technological resources among 551 operators in the same ecological, cultural and linguistic zones of Akwa Ibom State of Nigeria. Similar data collected between October 2007 and March 2008 were examined to quantify the differences in the attributes of literate and illiterate farmers. It was observed that the literate farmers have higher awareness, good management and willingness indices than illiterate farmers. Among others, education and training was recommended as a result of the important role they play in the efforts to mechanize Traditional Irrigation Practice (TIP) in Small Scale Irrigation in developing countries.

Udom, I. J.; Essien, A. I.

2010-01-01

48

Inventory of small-scale peat production  

Energy Technology Data Exchange (ETDEWEB)

The small-scale production of sod peat in Finland is, generally, production on farms for their own use. According to two postal questionnaires made by the Forestry Department of the Work Efficiency Association there were, in Finland, in 1980 77 and in 1984 136 small producers of sod peat. In the questionnaires, the production technology, economy, availability, conditions, areas and quantities of small-scale producers were identified. According to the questionnaires peat production on farms is mainly practised by using the farm's own labour and on their own or a hired production area. The larger part of small-scale production of peat is production of sod peat. Other peat products produced on farms are milled peat, agricultural peat and horticultural peat.

Eilavaara, H.

1986-01-01

49

SMALL SCALE BIOMASS FUELED GAS TURBINE ENGINE  

Science.gov (United States)

A new generation of small scale (less than 20 MWe) biomass fueled, power plants are being developed based on a gas turbine (Brayton cycle) prime mover. These power plants are expected to increase the efficiency and lower the cost of generating power from fuels such as wood. The n...

50

Small scale gas producer engine systems  

Energy Technology Data Exchange (ETDEWEB)

Small scale gas producer-engine systems are based on the combustion of coal or biomass and the use of the producer gas in existing internal combustion or specially developed engines. The monograph treats the types of gas producers, the fuel parameters, the conditioning of the producer gas, the internal combustion engine parameters and the economics of the introduction of small gas producer-engine systems particularly in Third World countries.

Kaupp, A.; Goss, J.R.

1984-01-01

51

Small scale power generation utilizing wave energy  

Energy Technology Data Exchange (ETDEWEB)

Presently a proposal is under investigation in the Department of Mechanical Engineering of the University of Cape Town, Republic of South Africa. The device has been termed the Differential Area Piston Compressor. The purpose of the device is to generate small quantities (kilowatts) of electricity, rather than the concept of large (megawatts) power units. The use of small scale power generators has special applications such as a floating buoy containing telemetry instrumentation or floating signal beacons. 15 resf.

Nurick, G.N.; Dutkiewicz, R.K.

1981-01-01

52

Small-scale rural bakery; Maaseudun pienleipomo  

Energy Technology Data Exchange (ETDEWEB)

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 flattening of Danish pastry dough was compared to doing using a machine. In addition to these, partial delayed baking and the method employing deep-freezing of raw products were compared to direct baking (of 21 loaves of rye bread, 140 small buns and 60 Danish pastries). Depending on the method, the time consumed varied between 4 h and 4 h 40 min. The advantage of delayed baking and deep-freezing of raw products may be seen in that the time consumed in making small buns and Danish pastries (ca. 1 h 20 min) can be spent at a less busy point in time and thereby concentrate on baking when the demand for bakery products is at its peak. Based on the results of the study, three functional spatial solutions were formulated for small-scale bakeries of different sizes and types. The functioning of the premises, machines, equipment, the usage of worker time, ergonomics, economic factors, quality of production, and microbiological safety were taken into consideration in the planning. (orig.) 29 refs.

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

1997-12-31

53

Philippines: Small-scale renewable energy update  

Energy Technology Data Exchange (ETDEWEB)

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.

NONE

1997-12-01

54

Small-Scale Hydroelectric Power Demonstration Project  

Energy Technology Data Exchange (ETDEWEB)

The US Department of Energy Field Office, Idaho, Small-Scale Hydroelectric Power Program was initiated in conjunction with the restoration of three power generating plants in Idaho Falls, Idaho, following damage caused by the Teton Dam failure on June 5, 1976. There were many parties interested in this project, including the state and environmental groups, with different concerns. This report was prepared by the developer and describes the design alternatives the applicant provided in an attempt to secure the Federal Energy Regulatory Commission license. Also included are correspondence between the related parties concerning the project, major design alternatives/project plan diagrams, the license, and energy and project economics.

Gleeson, L.

1991-12-01

55

The EMR small-scale flame test  

Energy Technology Data Exchange (ETDEWEB)

The small-scale flame test used by EMR since 1957 for certification of fire-resistant conveyor belting has been critcally re-examined. Some improvements in the apparatus and clarifications of the procedure are recommended. A summary of the certification experience with this test is given. One important conclusion is that the proposed elimination of the 'flowing air' component of the test would allow the passing of unacceptable belting. The tolerances required for the various parameters of the test have been estimated by a detailed study on one particular belting. These tolerances have been incorporated into the Canadian standard on fire-retardant conveyor belting.

Mintz, K.J.

1984-01-01

56

Small scale statistics of viscoelastic turbulence  

CERN Document Server

The small scale statistics of homogeneous isotropic turbulence of dilute polymer solutions is investigated by means of direct numerical simulations of a simplified viscoelastic fluid model. It is found that polymers only partially suppress the turbulent cascade below the Lumley scale, leaving a remnant energy flux even for large elasticity. As a consequence, fluid acceleration in viscoelastic flows is reduced with respect to Newtonian turbulence, whereas its rescaled probability density is left unchanged. At large scales the velocity field is found to be unaffected by the presence of polymers.

Berti, S; Boffetta, G; Celani, A; Musacchio, S

2006-01-01

57

Adopting small-scale production of electricity  

Energy Technology Data Exchange (ETDEWEB)

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.

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

2009-07-01

58

Expanded Small-Scale Shock Reactivity Test  

Science.gov (United States)

Explosives react from a strong shock, even in quantities too small for detonation. The potential for a new material to be an explosive can be evaluated from this shock reactivity. The recently developed small-scale shock reactivity test (SSRT)ootnotetextH. W. Sandusky, R. H. Granholm, D. G. Bohl, ``Small-Scale Shock Reactivity Test,'' NSWC Technical Report (in publication), Naval Surface Warfare Center, Indian Head, MD 20640 uses very high confinement to allow prompt reactions to occur in less than half-gram samples well below critical diameter, with the reactions quantified by a dent in a soft aluminum witness block. This test has been expanded to simultaneously measure both early and late-time reactions from a single sample subjected to the output from an RP-80 detonator. The sample apparatus is further confined within a small chamber instrumented with a pressure gage for internal air blast. This provides a measure of late-time reactions, such as from fuel/air combustion. Results are shown from several simultaneous early- and late-reaction measurements.

Granholm, Richard

2005-07-01

59

Billing scheme aims to foster small-scale renewable energy  

Energy Technology Data Exchange (ETDEWEB)

Toronto Hydro`s new billing program designed to encourage small-scale renewable energy technologies was discussed. The program gives customers choices that will save them money while protecting the environment. The net billing pilot program is the first of its kind in Canada. Canada Mortgage and Housing Corp.`s Healthy House is the first customer to sign up for the new billing option. A customer using photovoltaic energy on a bright and sunny day for example, may generate more electricity than is needed. The same customer may need to tap into Toronto Hydro at night to retrieve that energy to compensate for any shortfalls. The utility would give the customer credit on a reverse meter that measures both electricity consumption and generation.

Anon.

1997-07-11

60

Small scale anisotropy in turbulent shearless mixing  

CERN Multimedia

The generation of small-scale anisotropy in turbulent shearless mixing is numerically investigated. Data from direct numerical simulations at Taylor Reynolds' numbers between 45 and 150 show that there is not only a significant departure of the longitudinal velocity derivative moments from the values found in homogeneous and isotropic turbulence, but that the variation of skewness has an opposite sign for the components across the mixing layer and parallel to it. The anisotropy induced by the presence of a kinetic energy gradient has a very different pattern from the one generated by an homogeneous shear. The transversal derivative moments in the mixing are in fact found to be very small, which highlights that smallness of the transversal moments is not a sufficient condition for isotropy.

Tordella, Daniela

2011-01-01

 
 
 
 
61

Turbulent small-scale dynamo action in solar surface simulations  

CERN Multimedia

We demonstrate that surface convection in "realistic" solar simulations exhibits turbulent small-scale dynamo action. By presenting a derivation of the energy balance equation and transfer functions for compressible magnetohydrodynamics (MHD), we quantify the source of magnetic energy on a scale-by-scale basis. We rule out the two alternative mechanisms for the generation of small-scale magnetic field in the simulations: the tangling of magnetic field lines associated with the turbulent cascade and Alfvenization of small-scale velocity fluctuations ("turbulent induction"). Instead, we find the dominant source of small-scale magnetic energy is stretching by inertial-range fluid motions of small-scale magnetic field lines against the magnetic tension force to produce (against Ohmic dissipation) more small-scale magnetic field. The scales involved become smaller with increasing Reynolds number, which identifies the dynamo as a small-scale turbulent dynamo.

Graham, Jonathan Pietarila; Schuessler, Manfred

2010-01-01

62

Improving Agricultural Water Management through Low-Cost Small-Scale Irrigation Technologies in Kenya  

International Nuclear Information System (INIS)

[en] Agriculture is the second largest contributor to Kenya's gross domestic product and accounts for about 24% of GDP and 50% of revenue from exports. About half of Kenya's total agricultural output is subsistence production and farming provides employment to about 70% of the population. Approximately 80% of Kenyan farmland is classified as arid and semi-arid, with low and erratic rainfall, and food production is low with frequent crop failures. In order to ensure food security and sustainable farmer livelihoods there is an urgent need to improve agricultural water management practices that ensure optimal water use efficiency. A promising option is the use of low-cost small-scale irrigation technologies that are affordable for resource poor farmers. Through an IAEA technical cooperation project, the Kenya Agricultural Research Institute (KARI) has developed low-cost small-scale irrigation technologies to improve water- and nutrient use efficiencies of high-value crops, including cucumber, tomato, kale and lettuce. Yields of these crops were compared under rain-fed conditions, with irrigation using traditional hand-watering method and small-scale drip irrigation. Using the soil moisture neutron probe to determine the soil water content at any time during the growing season and the optimal timing and amount of water to be applied, KARI devised and employed small-scale low-cost drip irrigation technologies and compared yields under a variety of water management applications. Using these technologies, tomato yields of 9.7 t/ha were obtained under rain-fed conditions (with 221 mm of rainfall), 13.0 t/ha with traditional hand watering of 927 mm and 32 t/ha when applying 510 mm of water using small-scale drip irrigation, hence increasing the yield by 3.3 and 2.5 times, compared to rain-fed and hand watering, respectively. In the latter case, this yield increase was obtained despite a 45% reduction in the amount of water applied to the crop. Results also showed that a total of 580 t/ha of tomatoes can be obtained under the more optimal water and nutrient conditions provided in locally constructed greenhouses, where the 15N stable isotopic tracer was used to determine the fate of nitrogen (N) fertilisers in soils and tomato plants. Information obtained indicates that as much as 50% of the applied nitrogen can be saved when applied through drip irrigation while at the same time tomato yield could be maintained. A training manual for extension workers on the use of these drip irrigation systems has been developed, and training and dissemination of these technologies have been conducted through farmers' field days and discussion groups.

2011-01-01

63

Small Scale Foundries in Ghana: The challenges  

Directory of Open Access Journals (Sweden)

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.

Anthony ANDREWS; Emmanuel GIKUNOO

2011-01-01

64

Small-scale clad-effects study  

International Nuclear Information System (INIS)

The Small-Scale Clad Effects Study of the HSST Program was initiated to study the interaction of stainless cladding with flaws initiated in and propagating in base metal. From the designer's viewpoint stainless cladding is primarily viewed as a corrosion- and crud-prevention measure in light-water reactor vessel design, and except for its effect upon fatigue in thermal transients, its effect upon structural integrity has heretofore been largely disregarded. With the more recent focus of safety studies upon LOCA scenarios that emphasize the behavior of small flaws, it has become evident that stainless cladding may have a key role in the propagation and/or arrest of propagating flaws. A complicating factor in understanding the role of stainless cladding in this setting is its fracture toughness as a function of radiation dose and as a function of fabrication process for which meager data exist. The initial phase of this study has attempted to address this question by testing stainless-clad specimens that had been subjected to heat treatments to simulate beginning-of-life and end-of-life toughness conditions to fast-running cracks

1982-10-15

65

Options for small-scale sulfur recovery  

Energy Technology Data Exchange (ETDEWEB)

With the issuance by the Alberta Energy Resources Conservation Board and Alberta Environment of their report entitled Sulphur Recovery Guidelines for Sour Gas Plants in Alberta in August of 1988, the requirement in Alberta to recover sulfur was broadened to a sulfur content of 1 ton/D or greater in the inlet gas to a new sour-gas treating plant. This paper reviews the processes in use for recovering sulfur from sour-natural-gas streams that have a total sulfur content of 5 ton/D or less. These processes are the modified Claus process, the recycle Selectox process, and the reduction/oxidation processes LO-CAT and SulFerox. While the modified Claus process is used in large sulfur-recovery plants, the other processes may be more economical for sulfur recovery on a small scale. A description of the sour-gas treating and sulfur-recovery processes is given, and a comparison of estimated capital and operating costs for typical sour-gas streams is provided. All of the above processes are in operation in North America. Operating experiences with these processes in Alberta are discussed. The quality of the end-product sulfur varies among these processes, and the options for sulfur disposal are reviewed.

Royan, T. [Tartan Engineering Corp. Ltd. (Canada); Wichert, E. [Gascan Resources Ltd., Calgary, Alberta (Canada)

1997-11-01

66

Small-scale irradiated fuel electrorefining  

International Nuclear Information System (INIS)

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

1993-01-01

67

Small-scale accelerated pavement testing  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the results of a study conducted to explore the use of small-scale models of accelerated pavement testing (APT) devices to evaluate the performance of pavements in conjunction with full-scale tests. The motivation for the study was the availability of a model mobile load simulator (MMLS), which had been built originally to illustrate the operation of the full-scale mobile load simulator (MLS) under design at the time. The scaling requirements will be different depending on whether dynamic (inertia), viscous, or gravity effects are important. One must thus decide which one of these effects controls the behavior to try to reproduce it exactly. In the preliminary tests conducted with the MMLS, emphasis had been placed in reproducing accurately the viscoelastic behavior of the asphalt layer. The possibility of obtaining valid results, even if similitude is not maintained in relation to inertia forces, is explored in this paper. The effects of load frequency or velocity and the effects of layer thicknesses are studied. The total thickness of the model pavement, which must be finite, and its effects on displacements and strains are also considered. It is concluded that even when full similitude is not satisfied it is possible to obtain valid results that can be extrapolated to predict prototype performance if one were interested primarily in the behavior of the asphalt layer. Preliminary analyses should be conducted, however, to guide on the selection of the model dimensions.

Kim, S.M. [Korea Highway Corp., Kyunggi (Korea, Republic of). Highway Research Inst.; Hugo, F. [Univ. of Stellenbosch (South Africa). Inst. for Transport Technology; Roesset, J.M. [Univ. of Texas, Austin, TX (United States). Dept. of Civil Engineering

1998-03-01

68

Hall-magnetohydrodynamic small-scale dynamos.  

UK PubMed Central (United Kingdom)

Magnetic field generation by dynamo action is often studied within the theoretical framework of magnetohydrodynamics (MHD). However, for sufficiently diffuse media, the Hall effect may become non-negligible. We present results from three-dimensional simulations of the Hall-MHD equations subjected to random nonhelical forcing. We study the role of the Hall effect in the dynamo efficiency for different values of the Hall parameter. For small values of the Hall parameter, the small-scale dynamo is more efficient, displaying faster growth and saturating at larger amplitudes of the magnetic field. For larger values of the Hall parameter, saturation of the magnetic field is reached at smaller amplitudes than in the MHD case. We also study energy transfer rates among spatial scales and show that the Hall effect produces a reduction of the direct energy cascade at scales larger than the Hall scale, therefore leading to smaller energy dissipation rates. Finally, we present results stemming from simulations at large magnetic Prandtl numbers, which is the relevant regime in the hot and diffuse interstellar medium. In the range of magnetic Prandtl numbers considered, the Hall effect moves the peak of the magnetic energy spectrum as well as other relevant magnetic length scales toward the Hall scale.

Gómez DO; Mininni PD; Dmitruk P

2010-09-01

69

Hoopa Valley Small Scale Hydroelectric Feasibility Project  

Energy Technology Data Exchange (ETDEWEB)

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.

Curtis Miller

2009-03-22

70

Small scale combined woodgas power plant  

International Nuclear Information System (INIS)

[en] 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/m3) 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)

2003-04-24

71

Small-scale European forestry, an anticommons?  

Directory of Open Access Journals (Sweden)

Full Text Available In the article, I look at a phenomenon present in many small-scale European forests, their underutilisation. This underutilisation is obvious when it comes to timber extraction, but it can be argued that it is also present in relation to certain ecological or social uses of the forest. I do not want to judge this phenomenon in the article, but want to understand the reason this underutilisation occurs. Looking at forest resources worldwide and also in history, we conventionally face a problem of overuse. Taking first the property rights theory, I then refer to the tragedy of the anticommons to analyse the underutilisation. We observe a spatial anticommons in our forests. Even if the outcome of the tragedy of the commons and of the tragedy of the anticommons are opposed, I argue that analysing the solutions to the problems requires the same theoretical background. Both are collective action problems. However, compared to problems observed in forests elsewhere, the conditions for collective action are substantially different in the regarded case. In closing, I briefly compare forests as anticommons with other debates on the anticommons going on in the other debates around the commons.

Achim Schlueter

2008-01-01

72

Soil Properties as Influenced by Soil Fertility Management in Small Scale Maize Farms in Njoro, Kenya  

Directory of Open Access Journals (Sweden)

Full Text Available Most farmers are aware of soil fertility gradients within their farms which influence their management decisions and further accentuate these variations. The purpose of this study was to assess the effect of soil amendments on soil properties under farmers management. Soil sampling was done in 37 small scale maize farms in Njoro Division of Nakuru District at 0-20 cm depth. Results of a structured questionnaire showed that 65% of the farmers used inorganic fertilizers predominately diammonium phosphate (DAP), 15% used only farmyard manure, 15% used both organic and inorganic fertilizer, while 6% did not use any soil amendments. Most of the farms had a pH (CaCl2) of less than 5.2, 27% of the farms had a pH lower than 4.0. Organic carbon (C) ranged from 1.6 to 5.8%, with a median value of 2.6%. Most of the farms were phosphorus (P) deficient with an Olsen-P of less than 10 mg kg-1. All farms had sufficient amounts of extractable potassium (K). Total nitrogen (N) ranged from 0.12 to 0.33% with 97% of the farms with N content (>0.12%). Farms amended with farmyard manure had higher organic C and total N levels in Kikapu with correspondingly lower C: N ratios. Soil pH and total N were higher for farms with gentle and undulating slopes. Overall most of the farms were acidic and of moderate fertility. Liming increased maize biomass production in Njoro. This study underscores the need for organic inputs and regular soil testing for small scale farmers.

N.W. Mungai; A. Bationo; B. Waswa

2009-01-01

73

Economics of Small Scale Deep Litter System of Egg Production in Oredo Local Government Area of Edo State, Nigeria  

Directory of Open Access Journals (Sweden)

Full Text Available The general objective of this study is to examine the economics of small-scale deep litter system of egg production in Oredo Local Government Area Edo State, Nigeria. The Specific objectives are to determine the profitability in deep litter system of poultry production among small-scale farmers, to examine the socioeconomic characteristics of egg producers and to identify the constraints to egg production in the study area. Primary and secondary data were obtained from farmers. A purposive sampling of small-scale egg producers was carried first in the study area. Then a simple random sampling technique was then employed to select 182 egg producers using a well-structured questionnaire from the entire population of small-scale farmers. Descriptive statistics such as means and percentages were using to examine the socioeconomic characteristics. The gross margin analysis was used to determine the profitability. While the constraints to egg production was analyzed using the likert scale technique. The result of the analysis reveals that the average number of birds raised in deep litter is 760 birds. The study also shows that 68% and 32% of women and men produce eggs at this level respectively. The result of the study reveals that the fixed capital investment per bird was N 624.17 and total fixed cost less depreciation per bird was N.208.88 and total variable cost per bird was N 331.62. The study also reveals that total revenue from the sales of eggs per and other sources were N 3,749.22 per bird with a gross margin per bird of N 3,417.6 and a net profit of N 3,208.72. Finally the major constraints faced by the farmers are in the order of inadequate finance, high cost of feed, low egg price and high cost of medicine and vaccine Investments on Poultry building.

P.A. Ekunwe; O.O. Soniregun; J.O. Oyedeji

2006-01-01

74

The development for small scale soft X-ray spectrometer  

International Nuclear Information System (INIS)

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)

2004-01-01

75

Review of problems in the small-scale farm production of ethanol  

Energy Technology Data Exchange (ETDEWEB)

This report reviews the current status of small, farmer-operated ethanol production facilities. The characteristics and operating problems associated with present plants are reviewed with respect to technical, economic, and institutional issues. Information was obtained from recent publications and numerous telephone calls to state and federal officials and the producers themselves. It is concluded that, in most parts of the country, small-scale alcohol production has been reduced to relatively few farm plants, due primarily to several unfavorable economic factors. While both large and small facilities have been squeezed by rising feedstock costs and lower alcohol selling prices, the farmer-producer is burdened by additional constraints because of the small scale of his operations. It is not usually profitable for him to recover all the valuable by-products from the feedstock, such as gluten, corn oil, and carbon dioxide from corn conversion. He may not be able to use or market the wet alcohol and stillage he produces. Other difficulties often include high fuel costs, lack of financial and technical assistance, and excessive labor requirements.

White, H.M.

1983-07-01

76

Small-scale dynamical processes in quiet stellar atmospheres  

Energy Technology Data Exchange (ETDEWEB)

High-resolution observations of small-scale solar dynamics are discussed, taking into account the phase relations of high degree p-modes, power spectra of short-period oscillations, observations of high frequency waves using CCD array, dynamic signatures of quiet sun magnetic fields, and small-scale dynamical processes in the solar chromosphere. Other topics explored are related to projected improvements to high-resolution measurements, interpretation of high-resolution measurements, modelling of small-scale dynamical processes, convection and wave generation, interaction between solar convection and magnetism, low-resolution observations bearing on small-scale dynamical processes in the sun, the interpretation of low resolution observations, the accuracy of models obtained from low-resolution observations, and observations and interpretations of small-scale dynamical processes in stellar atmospheres. Attention is given to the observation of stellar granulation, and Zeeman broadening in solar type stars.

Keil, S.L.

1984-01-01

77

Potential for using indigenous pigs in subsistence-oriented and market-oriented small-scale farming systems of Southern Africa.  

UK PubMed Central (United Kingdom)

Indigenous pigs in South Africa are a source of food and economic autonomy for people in rural small-scale farming systems. The objective of the study was to assess the potential of indigenous pigs for improving communal farmer's livelihoods and to inform policy-makers about the conservation of indigenous pigs. Data were collected from 186 small-scale subsistence-oriented households and 102 small-scale market-oriented households using interviews and direct observations. Ninety-three percent of subsistence-oriented and 82 % of market-oriented households kept indigenous pigs such as Windsnyer, Kolbroek and non-descript crosses with exotic pigs mainly for selling, consumption and investment. Farmers in both production systems named diseases and parasites, followed by feed shortages, inbreeding and abortions as major constraints for pig production. Diseases and parasites were more likely to be a constraint to pig production in subsistence-oriented systems, for households where the head was not staying at home and for older farmers. Market-oriented farmers ranked productive traits such as fast growth rate, good meat quality and decent litter size as most important selection criteria for pig breeding stock, while subsistence-oriented farmers ranked good meat quality first, followed by decent growth rate and by low feed costs. We conclude that there is high potential for using indigenous pigs in subsistence-oriented production systems and for crossbreeding of indigenous pigs with imported breeds in market-oriented systems.

Madzimure J; Chimonyo M; Zander KK; Dzama K

2012-12-01

78

Small-Scale Variations of HI Spectra from Interstellar Scintillatio  

CERN Multimedia

I suggest that radio-wave scattering by the interstellar plasma, in combination with subsonic gradients in the Doppler velocity of interstellar HI, is responsible for the observed small-scale variation in HI absorption spectra of pulsars. Velocity gradients on the order of 0.05 to 0.3 km/s across 1 AU can produce the observed variations. I suggest observational tests to distinguish between this model and the traditional picture of small-scale opacity variations from cloudlets.

Gwinn, C R

2001-01-01

79

Development of small-scale peat production; Pienturvetuotannon kehittaeminen  

Energy Technology Data Exchange (ETDEWEB)

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.)

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

1997-12-01

80

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

UK PubMed Central (United Kingdom)

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Hammersvik E; Sandberg S; Pedersen W

2012-11-01

 
 
 
 
81

Rainwater harvesting for small-scale irrigation of maize in the Central Rift Valley, Ethiopia  

Science.gov (United States)

In the Central Rift Valley of Ethiopia, small scale farmers mostly rely on rainfall for crop production. The erratic nature of rainfall causes frequent crop failures and makes the region structurally dependent on food aid. Rainwater Harvesting (RWH) is a technique to collect and store runoff that could provide water for livestock, domestic use or small scale irrigation. Usually, such irrigation is promoted for high value crops, but in the light of regional food security it may become interesting to invest in irrigation of maize. In this research, two cemented RWH cisterns were investigated to determine their economic and social potential for supplemental irrigation of maize using drip irrigation. For this, data from test fields with irrigated maize and monitoring of water levels of the cisterns were used, as well as a survey under 30 farmers living close to the experimental site. The results show that catchment size and management should be in balance with the designed RWH system, to prevent too little runoff or flooding. An analysis with Cropwat 8.0 was used to investigate the possibility of irrigating maize with the observed amounts of water in the RWH cisterns. This would suffice for 0.3-0.8 ha of maize. For a RWH cistern with a drip irrigation system to be economically viable, the production on this acreage should become 3-4 ton/ha; 2.5 times higher than the current yield. But the biggest challenge would be to change the perception of respondents, who don't find it logical to spend precious water on a common crop like maize. Therefore, if the Ethiopian government considers the irrigation of maize to be important for regional food security, it is recommended to either subsidize the construction of RWH cisterns or provide credit on favourable terms.

Keesstra, Saskia; Hartog, Maaike; Muluneh, Alemayehu; Stroosnijder, Leo

2013-04-01

82

Small Scale Farming and Agricultural Products Marketing for Sustainable Poverty Alleviation in Nigeria  

Directory of Open Access Journals (Sweden)

Full Text Available Agricultural productions in developing countries have largely been on subsistence basis. The farmers only produce for their families and quantity of food produced are grossly inadequate for the growing population. There is increase widespread in the level of poverty amongst the people, most especially those living in the rural areas. Small scale farming has become one of the ways to tackle the problem of lack and poverty amongst these people. The paper therefore, examines how Small Scale farming assists in alleviating poverty in both rural and urban cities; most especially through marketing of agricultural products to the people. Relevant data were sought from the 356 respondents selected for the study through the Key Informant Interviews (KII). The Student T test and Chi square statistical techniques were further employed to test the Hypotheses stated in the study. Result of the finding reveals the importance of Small Scale Farming and Agricultural Products Marketing in poverty alleviation, most especially among the rural dwellers. It also indicated lack of access to fund as the major problem facing Small Scale Farming and increase cost of transportation as the major problem facing marketing of agricultural products. The Paper recommends that Individuals and Government can combat some of these challenges facing Small Scale Farming by providing adequate basic social infrastructures; make available more funds to the farmers and create more employment opportunities amongst others. The paper concludes that Agriculture no doubt, is an important sector that needs to be given attention in any developing economy. Key words: Small scale farming; Marketing; Rural dwellers; Key interview guide; Agricultural products and poverty Résumé: Les productions agricoles dans les pays en voie de développement étaient principalement sur la base de subsistance. Les agriculteurs ne produisent que pour leurs familles et la quantité des aliments produits est nettement insuffisante pour la population croissante. Il y a une augmentation généralisée de la pauvreté parmi la population, plus particulièrement ceux vivant dans les zones rurales. L'agriculture à petite échelle est devenue l'une des façons pour s'attaquer au problème du manque et de la pauvreté parmi cette population. L'article examine donc comment l'agriculture à petite échelle aide à soulager le problème de la pauvreté dans les villes rurales et urbaines; plus particulièrement à travers la commercialisation des produits agricoles. Des données pertinentes ont été recueillies auprès des 356 répondants sélectionnés pour l'étude en utilisant la méthode des interviews d'informateurs clés (IIC). Le test T et les techniques statistiques de Chi carré ont été employés plus tard pour tester les hypothèses énoncées dans l'étude. Le résultat de la recherche révèle l'importance de l'agriculture à petite échelle et la commercialisation des produits agricoles dans la réduction de la pauvreté, surtout parmi les habitants des zones rurales. Il a également indiqué le manque d'accès aux fonds comme le problème majeur auquel l'agriculture à petite échelle fait face et les coûts de transport croissant comme le problème majeur de commercialisation des produits agricoles. Le document recommande que les individus et le gouvernement peuvent combattre certains de ces défis confrontés par l'agriculture à petite échelle, en assurant des adéquates infrastructures sociales de base; mettant plus de fonds à la disposition des agriculteurs et créant davantage d'emplois entre autres. L'article conclut que l'agriculture est sans aucun doute un secteur important qui doit être accordé plus d'attention dans n'importe quelle économie en développement. Mots-clés: Petite agriculture à petite échelle; Commercialisation; Habitants ruraux; Guide d'interview clés; Produits agricoles et pauvreté

J. A. Bamiduro; Rotimi Ayodele Gbadeyan

2011-01-01

83

Concepções de agricultores ecológicos do Paraná sobre alimentação saudável Concepciones de agricultores ecológicos de Paraná (Sur de Brasil) sobre alimentación saludable Conceptions of healthy eating among ecological farmers in Paraná, Southern Brazil  

Directory of Open Access Journals (Sweden)

Full Text Available OBJETIVO: Descrever as concepções de agricultores ecológicos sobre alimentação saudável. MÉTODOS: Estudo com abordagem qualitativa. Entre janeiro e fevereiro de 2007, foram realizadas entrevistas em profundidade com o apoio de um roteiro com 11 mulheres e um homem residentes em comunidade agrícola de Rio Branco do Sul, PR, selecionados aleatoriamente dentre as 20 famílias de agricultores ecológicos desse município. RESULTADOS: Três categorias de análise foram identificadas: "tomada de consciência da alimentação saudável", "capacidade de compra" e "terra saudável". O significado da alimentação saudável para as mulheres agricultoras envolve a ideia de que os alimentos devem ser naturais, sem agrotóxicos nem produtos químicos industrializados. Cotidianamente o consumo de frutas, verduras e legumes somado ao básico feijão, arroz e carne deve ser abundante e a composição do prato deve visar à prevenção de obesidade e doenças crônico-degenerativas. O cuidado com os recursos naturais para garantir a produção de alimentos saudáveis, a segurança alimentar, a sustentabilidade do meio ambiente e a vida futura do planeta integram o conceito de alimentação saudável. CONCLUSÕES: O conhecimento, a autocrítica e o discernimento acompanharam as concepções em relação à alimentação saudável.OBJETIVO: Describir las concepciones de agricultores ecológicos sobre alimentación saludable. MÉTODOS: Estudio con abordaje cualitativo. Entre enero y febrero de 2007, se realizaron entrevistas en profundidad con el apoyo de un itinerario con 11 mujeres y un hombre residentes en comunidad agrícola de Rio Branco do Sul, Sur de Brasil, seleccionados aleatoriamente entre las 20 familias de agricultores ecológicos de este municipio. RESULTADOS: Tres categorías de análisis fueron identificadas: "tomada de consciencia de la alimentación saludable", "capacidad de compra" y "tierra saludable". El significado de la alimentación saludable para las mujeres agricultoras incluye la idea de que los alimentos deben ser naturales, sin pesticidas y productos químicos industrializados. Cotidianamente el consumo de frutas, verduras y legumbres sumado al básico grano, arroz y carne debe ser abundante y la composición del plato debe buscar la prevención de obesidad y enfermedades crónico-degenerativas. El cuidado con los recursos naturales para garantizar la producción de alimentos saludables, la seguridad alimentaria, la sustentabilidad del medio ambiente y la vida futura del planeta integran el concepto de alimentación saludable. CONCLUSIONES: El conocimiento, la autocrítica y el discernimiento acompañaron las concepciones con relación a la alimentación saludable.OBJECTIVE: To describe ecological farmers' conceptions of healthy eating. METHODS: Study with a qualitative approach. In January and February 2007, supported by a guide, in-depth interviews were conducted with 11 women and one man who were living in an agricultural community in Rio Branco do Sul, Southern Brazil. The interviewees were selected randomly from among the 20 ecological farming families in this municipality. RESULTS: Three analysis categories were identified: "awareness of healthy eating"; "purchasing power" and "healthy land". The significance of healthy eating for the female farmers involved the idea that foods should be natural, without agricultural pesticides or manufactured chemical products. The daily routine should include abundant consumption of fruits, greens and other vegetables, in addition to the basic rice, beans and meat, and the composition of dishes should aim towards prevention of obesity and chronic-degenerative diseases. Care regarding natural resources in order to ensure production of healthy foods, food safety, environmental sustainability and the future of life on the planet form part of the concept of healthy eating. CONCLUSIONS: Knowledge, self-criticism and discernment accompanied the conceptions of healthy eating.

Erica Ell; Denise Oliveira e Silva; Eleusis Ronconi de Nazareno; Alfio Brandenburg

2012-01-01

84

Occupational health of Turkish Aegean small-scale fishermen.  

UK PubMed Central (United Kingdom)

BACKGROUND: Fishing has always been a dangerous occupation, and numerous factors have a direct or indirect impact on the health of fisherman. AIMS: To examine the health, safety and working conditions of small-scale fishing fleets in the Turkish Aegean Sea coasts. METHODS: Data were obtained from a questionnaire distributed to a random sample of small-scale fishermen along the Aegean Sea coast. Data collection took place between September 2009 and January 2010. RESULTS: Out of 5714 Aegean Sea small-scale fishermen, 1166 from 76 fishing ports participated. Twenty-nine per cent of fishermen did not have any social security cover. The most prevalent health problems (using International Classification of Diseases and Related Health Problems 10th Revision [ICD-10]) found were musculoskeletal problems (e.g. discopathies, muscular strain, rheumatism) and eye, ear-nose, digestive and urinary system problems. Alcohol consumption was high (68%) in fishermen and 72% reported that they smoked more during fishing trips. Health problems appeared to be associated with a number of factors including migrant status, income satisfaction, rank, type of fishing and cumulative work per year. CONCLUSIONS: In Turkey, small-scale fishermen experience a significant number of health problems and have unhealthy lifestyles. Interventions designed to improve working conditions of small-scale fishermen could help to reduce the number of occupational injuries, which in turn may impact positively on their health. Prevention policies to reduce alcohol and tobacco consumption should also be developed.

Percin F; Akyol O; Davas A; Saygi H

2012-03-01

85

Farmer's Market Standard Measurement  

CERN Multimedia

Many people like to buy fresh fruits and vegetables from the farmers market. The farmers market is a special market where farmers sell the crops they grow. They sell different crops at different times of the year. Sometimes the farmers even make sweet desserts with their fresh fruit. Follow this farming family through the seasons and learn how to weigh and measure food along the way. How many apples do you think they need to make an apple pie? 32pp.

Hunt, Dawson J

2010-01-01

86

Universal magnetohydrodynamic turbulence and small-scale dynamo  

International Nuclear Information System (INIS)

Magnetohydrodynamic (MHD) turbulence is common in many space physics and astrophysics environments. A well-conductive fluid amplifies initial magnetic fields in a process called small-scale dynamo. Below the equipartition scale for kinetic and magnetic energies, the spectrum is steep (Kolmogorov -5/3) and is represented by critically balanced strong MHD turbulence. In this paper, we report the basic reasoning behind the universal nonlinear small-scale dynamo and the inertial range of MHD turbulence. We measured the efficiency of the small-scale dynamo CE = 0.05, the Kolmogorov constant CK = 4.2 and the anisotropy constant CA = 0.34 for MHD turbulence in high-resolution direct numerical simulations.

2012-01-01

87

Evaluation of Small-Scale Laterally Loaded Monopiles in Sand  

DEFF Research Database (Denmark)

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 diameter effect on laterally loaded non-slender piles in sand is evaluated by means of results from six small-scale laboratory tests, numerical modelling of the same test setup and existing theory. From the numerical models, p?y curves are derived and compared to current design regulations. The recommendations in API (1993) and DNV (1992) are observed to be in poor agreement with the numerically obtained p?y curves. The initial stiffness, Epy*, of the p?y curves is found to increase with increasing pile diameter. Considerable uncertainties are observed to be related to small-scale testing, and the evaluations clearly indicate that the accuracy of small-scale testing is increased when increasing the pile diameter and applying overburden pressure.

Roesen, Hanne Ravn; Thomassen, Kristina

2011-01-01

88

Concepções de agricultores ecológicos do Paraná sobre alimentação saudável/ Conceptions of healthy eating among ecological farmers in Paraná, Southern Brazil/ Concepciones de agricultores ecológicos de Paraná (Sur de Brasil) sobre alimentación saludable  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese OBJETIVO: Descrever as concepções de agricultores ecológicos sobre alimentação saudável. MÉTODOS: Estudo com abordagem qualitativa. Entre janeiro e fevereiro de 2007, foram realizadas entrevistas em profundidade com o apoio de um roteiro com 11 mulheres e um homem residentes em comunidade agrícola de Rio Branco do Sul, PR, selecionados aleatoriamente dentre as 20 famílias de agricultores ecológicos desse município. RESULTADOS: Três categorias de análise foram (more) identificadas: "tomada de consciência da alimentação saudável", "capacidade de compra" e "terra saudável". O significado da alimentação saudável para as mulheres agricultoras envolve a ideia de que os alimentos devem ser naturais, sem agrotóxicos nem produtos químicos industrializados. Cotidianamente o consumo de frutas, verduras e legumes somado ao básico feijão, arroz e carne deve ser abundante e a composição do prato deve visar à prevenção de obesidade e doenças crônico-degenerativas. O cuidado com os recursos naturais para garantir a produção de alimentos saudáveis, a segurança alimentar, a sustentabilidade do meio ambiente e a vida futura do planeta integram o conceito de alimentação saudável. CONCLUSÕES: O conhecimento, a autocrítica e o discernimento acompanharam as concepções em relação à alimentação saudável. Abstract in spanish OBJETIVO: Describir las concepciones de agricultores ecológicos sobre alimentación saludable. MÉTODOS: Estudio con abordaje cualitativo. Entre enero y febrero de 2007, se realizaron entrevistas en profundidad con el apoyo de un itinerario con 11 mujeres y un hombre residentes en comunidad agrícola de Rio Branco do Sul, Sur de Brasil, seleccionados aleatoriamente entre las 20 familias de agricultores ecológicos de este municipio. RESULTADOS: Tres categorías de análi (more) sis fueron identificadas: "tomada de consciencia de la alimentación saludable", "capacidad de compra" y "tierra saludable". El significado de la alimentación saludable para las mujeres agricultoras incluye la idea de que los alimentos deben ser naturales, sin pesticidas y productos químicos industrializados. Cotidianamente el consumo de frutas, verduras y legumbres sumado al básico grano, arroz y carne debe ser abundante y la composición del plato debe buscar la prevención de obesidad y enfermedades crónico-degenerativas. El cuidado con los recursos naturales para garantizar la producción de alimentos saludables, la seguridad alimentaria, la sustentabilidad del medio ambiente y la vida futura del planeta integran el concepto de alimentación saludable. CONCLUSIONES: El conocimiento, la autocrítica y el discernimiento acompañaron las concepciones con relación a la alimentación saludable. Abstract in english OBJECTIVE: To describe ecological farmers' conceptions of healthy eating. METHODS: Study with a qualitative approach. In January and February 2007, supported by a guide, in-depth interviews were conducted with 11 women and one man who were living in an agricultural community in Rio Branco do Sul, Southern Brazil. The interviewees were selected randomly from among the 20 ecological farming families in this municipality. RESULTS: Three analysis categories were identified: " (more) awareness of healthy eating"; "purchasing power" and "healthy land". The significance of healthy eating for the female farmers involved the idea that foods should be natural, without agricultural pesticides or manufactured chemical products. The daily routine should include abundant consumption of fruits, greens and other vegetables, in addition to the basic rice, beans and meat, and the composition of dishes should aim towards prevention of obesity and chronic-degenerative diseases. Care regarding natural resources in order to ensure production of healthy foods, food safety, environmental sustainability and the future of life on the planet form part of the concept of healthy eating. CONCLUSIONS: Knowledge, self-criticism and discernment accompanied the conceptions of heal

Ell, Erica; Oliveira e Silva, Denise; Nazareno, Eleusis Ronconi de; Brandenburg, Alfio

2012-04-01

89

Small-scale dynamo at low magnetic Prandtl numbers.  

UK PubMed Central (United Kingdom)

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(?)??^{?}, where v(?) is the eddy velocity at a scale ?. We explore turbulent spectra ranging from incompressible Kolmogorov turbulence with ?=1/3 to highly compressible Burgers turbulence with ?=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-?)/(1+?)}. 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.

Schober J; Schleicher D; Bovino S; Klessen RS

2012-12-01

90

Small-scale dynamo at low magnetic Prandtl numbers.  

Science.gov (United States)

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(?)??^{?}, where v(?) is the eddy velocity at a scale ?. We explore turbulent spectra ranging from incompressible Kolmogorov turbulence with ?=1/3 to highly compressible Burgers turbulence with ?=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-?)/(1+?)}. 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. PMID:23368064

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

2012-12-26

91

Small scale wood combustion in Germany. Recent research and trends  

Energy Technology Data Exchange (ETDEWEB)

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.

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

1998-12-31

92

Development of large and small scale seismic crosshole techniques  

International Nuclear Information System (INIS)

A system for seismic crosshole measurements has been designed, built and tested. The system can be used both for small scale (ie 10 - 200 m) and large scale (ie 200 - 1000 m) operations. A tomographic inversion theory has been developed, which proves that the method can give unique results if the measuring geometry is carefully planned. Efficient algorithms for computation of tomographic pictures have been developed and coded. Two field tests have been carried out successfully. The small scale test gave a detailed picture, whereas in the large scale test only large features could be seen

1990-01-01

93

Trends in Agriculturally-Relevant Rainfall Characteristics for Small-scale Agriculture in Northern Ghana  

Directory of Open Access Journals (Sweden)

Full Text Available Normal 0 false false false EN-US X-NONE X-NONE st1:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} This study set out to investigate the trends of agriculturally-relevant rainfall characteristics among small-scale farmers in the rainfall-sensitive dry savanna agro ecological zone of northern Ghana.  Interviews are used to identify characteristics of rainfall which are deemed by the farmers as important in their food production. Time series daily rainfall data from 1960-2007 is then used to identify trends in these variables which include the amount and temporal distribution of rainfall, occurrence of extreme daily rainfall events, the onset of rains, risk of dry spells and coefficient of variability of rains. The risk of dry spells for varying number of days following the planting period is computed using first-order Markov chain modeling. We find that there is a significant increase in mean rainfall per rain day and the coefficient of variation or summer rainfall amounts. No significant change in the onset of rains, the annual rainfall amount and maximum rainfall days are established. However, a significant decrease in the number of rain days and the probability of dry spells of up to seven and eleven days in the first four weeks of the planting season is revealed. There is need for development of an agricultural policy framework designed to understand the growing risks associated with agricultural production among small-scale farmers, and to improve management practices to accommodate and adapt to the new challenges of varying rainfall.

Genesis Tambang Yengoh; Frederick Ato Armah; Edward Ebo Onumah; Justice O. Odoi

2010-01-01

94

Involvement of small-scale dairy farms in an industrial supply chain: when production standards meet farm diversity.  

UK PubMed Central (United Kingdom)

In certain contexts, dairy firms are supplied by small-scale family farms. Firms provide a set of technical and economic recommendations meant to help farmers meet their requirements in terms of the quantity and quality of milk collected. This study analyzes how such recommendations may be adopted by studying six farms in Brazil. All farms are beneficiaries of the country's agrarian reforms, but they differ in terms of how they developed their activities, their resources and their milk collection objectives. First, we built a technical and economic benchmark farm based on recommendations from a dairy firm and farmer advisory institutions. Our analysis of the farms' practices and technical and economic results show that none of the farms in the sample apply all of the benchmark recommendations; however, all farms specialized in dairy production observe the main underlying principles with regard to feeding systems and breeding. The decisive factors in whether the benchmark is adopted and successfully implemented are (i) access to the supply chain when a farmer establishes his activity, (ii) a grasp of reproduction and forage production techniques and (iii) an understanding of dairy cattle feed dietary rationing principles. The technical problems observed in some cases impact the farms' dairy performance and cash position; this can lead to a process of disinvestment. This dynamic of farms facing production standards suggests that the diversity of specialized livestock farmers should be taken into account more effectively through advisory approaches that combine basic zootechnical training with assistance in planning farm activities over the short and medium term.

Bernard J; Le Gal PY; Triomphe B; Hostiou N; Moulin CH

2011-05-01

95

Economics of resource use in small-scale rice production: A case study of Niger state, Nigeria  

Directory of Open Access Journals (Sweden)

Full Text Available This paper analyses the use of resources and farm income among small-scale rice farmers in Niger State. A sample set of 120 farm households was selected using a simple random sampling technique to generate primary data. The average farm size was 2.8ha and the average yield was 5,041.47 kg/ha. The average variable cost, average fixed cost and average net farm income per hectare were N28,839.30, N3,160.45 and N30,463.10, respectively. The major factors that significantly influenced the level of technical inefficiency with their corresponding maximum likelihood estimates were age (0.0065), household size (0.0069), farming experience (0.0001), extension contact (0.0177) and membership of a co-operative (0.2824). Pests and diseases, floods, non-passable roads and inadequate finance were the major problems of rice production. Based on these findings, it was concluded that the study area had a great potential to increase rice production and a farmer’s income if efforts could be made for widespread adoption of new technologies and by addressing those constraints herewith identified. However, an effort should also be made to mobilize and encourage farmers to form co-operatives to enable farmers to pool their resources and increase the scale of operations. Furthermore, the government should make production inputs like fertilizer, improved seeds and agro-chemicals available to farmers at the right time and at subsidized rates because production inputs were some of the most important limiting resources that adversely affected rice production in the study area.

Abdullahi A. et. al

2012-01-01

96

Working Capital Management of Small Scale Industries in Rajasthan  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Small scale industry (SSI) plays an important role in the economy of the state Rajasthan of India. In spite of all the odds, the SSI sector has emerged as India’s engine of growth in the new millennium. The SSI sector in India contribute almost 40% of the gross industrial value added, the study is u...

Bashar Matarneh

97

Simulations of regional atmospheric flows on small scale topographical models  

Energy Technology Data Exchange (ETDEWEB)

Various aspects on how to adapt existing physical modelling techniques in order to simulate regional atmospheric flows on small scale topographical models are presented. The possibilities and limitations of such models are described, based on those considerations relevant to similarity and, by comparing models with different scales. Several practical aspects of model construction are underlined.

Hertig, J.A.; Liska, P.

1983-12-01

98

Small-scale dynamo action in primordial halos  

Science.gov (United States)

The first galaxies form due to gravitational collapse of primordial halos. During this collapse, weak magnetic seed fields get amplified exponentially by the small-scale dynamo - a process converting kinetic energy from turbulence into magnetic energy. We use the Kazantsev theory, which describes the small-scale dynamo analytically, to study magnetic field amplification for different turbulent velocity correlation functions. For incompressible turbulence (Kolmogorov turbulence), we find that the growth rate is proportional to the square root of the hydrodynamic Reynolds number, Re1/2. In the case of highly compressible turbulence (Burgers turbulence) the growth rate increases proportional to Re1/3. With a detailed chemical network we are able to follow the chemical evolution and determine the kinetic and magnetic viscosities (due to Ohmic and ambipolar diffusion) during the collapse of the halo. This way, we can calculate the growth rate of the small-scale dynamo quantitatively and predict the evolution of the small-scale magnetic field. As the magnetic energy is transported to larger scales on the local eddy-timescale, we obtain an estimate for the magnetic field on the Jeans scale. Even there, we find that equipartition with the kinetic energy is reached on small timescales. Dynamically relevant field structures can thus be expected already during the formation of the first objects in the Universe.

Schober, Jennifer; Schleicher, Dominik R. G.; Klessen, Ralf S.; Federrath, Christoph; Bovino, Stefano; Glover, Simon; Banerjee, Robi

2013-07-01

99

DISPOSAL OF SMALL-SCALE FISH PROCESSING WASTE THROUGH COMPOSTING  

Science.gov (United States)

Large catfish processors in the U.S. typically recycle fish waste into fish meal. For small-scale processors or aquaculture research facilities, fish waste disposal can be problematic. We adapted a design developed for composting wastes from Minnesota fishing lodges and tested it for suitability fo...

100

Monitoring Results of a Small Scale CHCP System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A small scale trigeneration system for combined heat, cold and power production was developed and installed at the Laboratório Nacional de Energia e Geologia, I.P. campus in Lisbon, Portugal. This system is one of the twelve experimental trigeneration systems being developed and tested across Europe...

 
 
 
 
101

Small-Scale Retailers in an Island Town  

Directory of Open Access Journals (Sweden)

Full Text Available This paper examines the competition faced by small-scale general store and textile retailing in an island town in Malaysia. The study was carried out in Labuan Town in Labuan Island of East Malaysia. A qualitative research design was utilized, involving primarily interview data which were collected from 12 in-depth interviews with 6 sundry and general store retailers and 6 textile retailers. Content analysis was executed to analyse the narrative data. The findings reveal that large store retailing negatively impact the small traders on trade diversion, but also positively modernize their retail formats. Competition was intense for the town centre small-scale retailers who were facing multiple competitions from large retailers and bazaar retailers in the town centre, small-scale retailers from the rural areas, as well as place competition in the region. The study suggests the need for creative response of the local authority in place making and balanced development, coupled with the strategic response of small-scale retailers in cultivating local enterprise.

Sivapalan Selvadurai; A. C. Er; N. Lyndon; A. Buang; M. J. Mohd. Fuad; A. Habibah; J. Hamzah; A. M. Azima; A. B. Junaidi; Mohd Yusof Hussein

2013-01-01

102

Prevalence of gastrointestinal helminths and anthelmintic resistance on small-scale farms in Gauteng Province, South Africa.  

Science.gov (United States)

The present study was conducted to determine the prevalence and distribution of gastrointestinal helminths, to detect the presence of anthelmintic resistance in livestock from small-scale farms and to determine the level of helminthosis awareness among small-scale farmers in Gauteng Province, South Africa. Blood and faecal samples were collected from cattle (n?=?314), sheep (n?=?256) and goats (n?=?311). Faecal egg counts and cultures were done, helminth genera identified and packed cell volume was assessed to detect anaemia. A faecal egg count reduction test was used to determine anthelmintic resistance against albendazole (7.5 mg/kg), levamisole (5 mg/kg) and ivermectin (0.2 mg/kg) on five small ruminant farms. A high prevalence of both nematodes and trematodes was observed; however, only 1 % of cattle had high nematode egg counts compared to goats (30 %) and sheep (32 %). Only 5 % of the animals were anaemic. Haemonchus and Calicophoron were the most dominant helminth genera in the studied ruminants. Anthelmintic resistance was detected against the three tested drugs on all the screened farms, except against albendazole and levamisole in sheep from Hammanskraal and Nigel, respectively. About 88 % of interviewed farmers were aware of veterinary helminthosis, 67 % treated against helminths and 83 % provided their livestock with nutritional supplements. This study showed that a high prevalence of helminthosis and anthelmintic resistance does occur in the study area, thus relevant strategic interventions are recommended. PMID:23065406

Tsotetsi, Ana Mbokeleng; Njiro, Stephen; Katsande, Tendai Charles; Moyo, Gugulethu; Baloyi, Faculty; Mpofu, Jaison

2012-10-14

103

Prevalence of gastrointestinal helminths and anthelmintic resistance on small-scale farms in Gauteng Province, South Africa.  

UK PubMed Central (United Kingdom)

The present study was conducted to determine the prevalence and distribution of gastrointestinal helminths, to detect the presence of anthelmintic resistance in livestock from small-scale farms and to determine the level of helminthosis awareness among small-scale farmers in Gauteng Province, South Africa. Blood and faecal samples were collected from cattle (n?=?314), sheep (n?=?256) and goats (n?=?311). Faecal egg counts and cultures were done, helminth genera identified and packed cell volume was assessed to detect anaemia. A faecal egg count reduction test was used to determine anthelmintic resistance against albendazole (7.5 mg/kg), levamisole (5 mg/kg) and ivermectin (0.2 mg/kg) on five small ruminant farms. A high prevalence of both nematodes and trematodes was observed; however, only 1 % of cattle had high nematode egg counts compared to goats (30 %) and sheep (32 %). Only 5 % of the animals were anaemic. Haemonchus and Calicophoron were the most dominant helminth genera in the studied ruminants. Anthelmintic resistance was detected against the three tested drugs on all the screened farms, except against albendazole and levamisole in sheep from Hammanskraal and Nigel, respectively. About 88 % of interviewed farmers were aware of veterinary helminthosis, 67 % treated against helminths and 83 % provided their livestock with nutritional supplements. This study showed that a high prevalence of helminthosis and anthelmintic resistance does occur in the study area, thus relevant strategic interventions are recommended.

Tsotetsi AM; Njiro S; Katsande TC; Moyo G; Baloyi F; Mpofu J

2013-03-01

104

SUBSTANTIATION OF ECONOMIC DECISIONS IN THE SMALL-SCALE BUSINESS  

Directory of Open Access Journals (Sweden)

Full Text Available Formation of economic decisions in the small-scale business takes a leading place in a control system of the enterprise. On a choice of a variant of the decision depends not only the efficiency, but also a survival of a small enterprise. Therefore in the small-scale business the scientists and businessmen give to a substantiation of the economic decision prime attention.The substantiation of the economic decision occurs in the course of planning and regulation of activity of a small enterprise. The correct substantiation of strategic and tactical decisions, to what in the course of a substantiation it is necessary to apply corresponding methods of the complex analysis, is especially important.Limitation of resources of the small businessman causes the necessity of using by him the systems of support and decision-making in the course of a substantiation of economic decisions. Such systems should have a corresponding database, the interface and algorithmic maintenance.

S. Krekotun

2012-01-01

105

Biofuels in Africa: growing small-scale opportunities  

Energy Technology Data Exchange (ETDEWEB)

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.

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

2009-11-15

106

Working Capital Management of Small Scale Industries in Rajasthan  

Directory of Open Access Journals (Sweden)

Full Text Available Small scale industry (SSI) plays an important role in the economy of the state Rajasthan of India. In spite of all the odds, the SSI sector has emerged as India’s engine of growth in the new millennium. The SSI sector in India contribute almost 40% of the gross industrial value added, the study is undertaken by taking 5 years data from secondary source. From this study, it has been found the working capital management is to decide the pattern of financing of the current assets, which is one of the biggest problems of working capital management. The SSIs has to decide about the sources of funds which can be avail to make investment in the current assets. The problem of working capital management of small-scale industries is not new.

Bashar Matarneh

2012-01-01

107

The small-scale structure of quantum spacetime  

CERN Document Server

Planck-scale quantum spacetime undergoes probabilistic local curvature fluctuations whose distributions cannot explicitly depend on position otherwise vacuum's small-scale quantum structure would fail to be statistically homogeneous. Since the collection of fluctuations is a many-body system, the natural explanation for their position-independent statistics is that they are in equilibrium with each other and distributed at maximum entropy. Consequently, their probability distributions obey the laws of statistical physics which enforces small-scale smoothness, prevents the homogeneity-violating diffusion found in any free quantum system, and maintains decoherence. Their entropy, calculated using the explicitly-constructed phase space of the Riemann whose statistics are derived using a background-independent graviton exchange ensemble, is proportional to the Einstein-Hilbert action evaluated on the macroscopic expected geometry and includes a small, positive cosmological constant. Entropy maximization yields qu...

Burton, Christopher D

2012-01-01

108

Computer model for small-scale hydropower policy analysis  

Energy Technology Data Exchange (ETDEWEB)

A computer simulation model of the obstacles and incentives to the development of small-scale hydropower in New England is presented. It serves as an effective communication tool between analysts and policymakers, helping them understand the implication of policy recommendations to increase small-hydropower development. Only four of the factors affecting development are included in the model: economics, licensing, construction, and retirement. From a financial point of view, the most promising developers are municipalities and investor-owned utilities. In the year 2000, it may be feasible to develop sites costing approximately double the present costs. Small-scale hydropower will generally be developed now only if developers are willing to accept risks. The inflationary effects of licensing and the complexity of the process might be the major disincentives associated with licensing.

Kirshen, P.H. (Virginia Polytechnic Inst. and State Univ., Blacksburg); Amlin, J.S.

1981-03-01

109

Bosons - Hot dark matter with small-scale power  

Energy Technology Data Exchange (ETDEWEB)

An alternative hot dark matter scenario which considers low-mass bosons rather than neutrinos is suggested which has much more small-scale power than the neutrino hot dark matter model while keeping the power peak at large scales comparable to the comoving length scale set by neutrino free-streaming. The reason is that, for a given particle mass, the Bose-Einstein distribution has more low-velocity particles than the corresponding Fermi-Dirac distribution. Therefore, an appreciable fraction of particles stay close to their initial positions, so that even though the mean free-streaming length is similar to that for neutrinos, a fair amount of power survives on small scales. 9 refs.

Madsen, J. (Aarhus, University, Denmark (USA))

1991-04-01

110

Bosons - Hot dark matter with small-scale power  

International Nuclear Information System (INIS)

An alternative hot dark matter scenario which considers low-mass bosons rather than neutrinos is suggested which has much more small-scale power than the neutrino hot dark matter model while keeping the power peak at large scales comparable to the comoving length scale set by neutrino free-streaming. The reason is that, for a given particle mass, the Bose-Einstein distribution has more low-velocity particles than the corresponding Fermi-Dirac distribution. Therefore, an appreciable fraction of particles stay close to their initial positions, so that even though the mean free-streaming length is similar to that for neutrinos, a fair amount of power survives on small scales. 9 refs

1991-01-01

111

Development of a small-scale catalytic gas turbine combustor  

Energy Technology Data Exchange (ETDEWEB)

Catalytically supported thermal combustion can provide low NO/sub x/ emissions with gaseous and distillate fuels while maintaining high combustion efficiency. For stationary gas turbines, catalytic combustion may be the only emerging technology that can cost effectively meet recent federal regulations for NO/sub x/ emissions. Under EPA sponsorship, a small-scale, catalytic gas turbine combustor was developed to evaluate transient and steady state combustor performance. 15 refs.

Anderson, S.J.; Friedman, M.A.; Krill, W.V.; Kesselring, J.P.

1982-01-01

112

An introduction to small scale reflection in Coq  

Directory of Open Access Journals (Sweden)

Full Text Available This tutorial presents the SSReflect extension to the Coq system. This extension consists of an extension to the Coq language of script, and of a set of libraries, originating from the formal proof of the Four Color theorem. This tutorial proposes a guided tour in some of the basic libraries distributed in the SSReflect package. It focuses on the application of the small scale reflection methodology to the formalization of finite objects in intuitionistic type theory.

Georges Gonthier; Assia Mahboubi

2010-01-01

113

Legal factors affecting the financing of small scale hydroelectric projects  

Energy Technology Data Exchange (ETDEWEB)

An introduction to the major business organizational options open to small-scale hydroelectric (SSH) projects is given. The major federal income tax treatments of these options are compared. Significant general federal income tax factors affecting SSH projects are reintroduced and explained. Some of the special federal income tax problem areas in SSH development are isolated. Tax benefit flow through or transfer mechanisms are discussed. Tax exempt financing opportunities for private SSH projects are reviewed. (MHR)

Wilson, W.H.; Ringo, M.J.; Forgione, N.

1983-09-01

114

Small-scale cannabis growers in Denmark and Finland.  

UK PubMed Central (United Kingdom)

AIMS: To compare domestic cannabis cultivation in Denmark and Finland to describe national characteristics in small-scale cannabis growing. DESIGN: A Web survey conducted among small-scale cannabis growers in Denmark (June to November 2008) and Finland (May to June 2009). PARTICIPANTS: Current cannabis growers (Denmark, 401; Finland, 1,054). MEASUREMENTS: Comparisons in regard to social background, growing history, practices, purposes and motives of growing, and perceptions of risks. FINDINGS: Cannabis was cultivated primarily for own use, but sharing with friends and avoiding criminal circles also were significant motives for growing. Finnish growers prioritized indoor cultivation, whereas the Danes were more in favor of open-air plantations. Risks of getting caught by the police were observed to be greater in Finland. Growing for medical purposes was twice as prevalent in Finland as in Denmark. CONCLUSIONS: Cannabis growing is a stronger and more novel phenomenon in Finland than in Denmark, but both countries have been influenced by international trends. Finnish and Danish small-scale cannabis cultivators can be considered to be ideologically oriented lifestyle growers. Differences in the magnitude of the phenomenon may reflect differences in the availability and quality of cannabis in national drug markets. The Internet had promoted the spreading of the trend.

Hakkarainen P; Frank VA; Perälä J; Dahl HV

2011-01-01

115

Small-scale lipid-membrane structure: simulation versus experiment.  

UK PubMed Central (United Kingdom)

Recently, it has become obvious that the conventional picture of the fluid lipid-bilayer component of biological membranes being a fairly structureless 'fluid mosaic' solvent is far from correct. The lipid bilayer displays distinct static and dynamic structural organization on a small scale, for example in terms of differentiated lipid domains, and evidence is accumulating that these structures are of importance for the functioning of biological membranes, including the activity of membrane-bound enzymes and receptors and morphological changes at the cell surface. Insight into the relationship between this small-scale structure and biological functioning holds promise for a more rational approach to modulate function via manipulation of the lipid microenvironment and the lipid/protein interface in particular. Computer simulation has proved to be a useful tool in investigating membrane structure on a small scale-specifically the nanometer scale (1-100 nm), which is in between the molecular scale accessible by various spectroscopic techniques and molecular dynamics calculations, and the micrometer scale accessible by scattering and microscopy techniques.

Mouritsen OG; Jørgensen K

1997-08-01

116

Subcritical small-scale dynamos at low magnetic Prandtl numbers  

CERN Document Server

Saturated small-scale dynamo solutions driven by isotropic non-helical turbulence are presented at low magnetic Prandtl numbers down to 0.02, and, with less certainty, down to 0.01. In that range, most of the energy is dissipated via Joule heat and, in agreement with earlier results for helical large-scale dynamos, kinetic energy dissipation is shown to diminish proportional to the square root of the magnetic Prandtl number. Nevertheless, the rms magnetic field strength of the small-scale dynamo is found to depend only weakly on the value of the magnetic Prandtl number and decreases by about a factor of 2 as its value is decreased from 1 to 0.01. Restarting a simulation with a down-scaled magnetic field leads to decay, giving evidence for a subcritical nature of small-scale dynamos at low magnetic Prandtl numbers. This is argued to be a consequence of a suppression of the bottleneck seen in the kinetic energy spectrum in the absence of a dynamo and, more generally, a suppression of kinetic energy near the dis...

Brandenburg, Axel

2011-01-01

117

Dislocation dynamics simulations of plasticity at small scales  

Energy Technology Data Exchange (ETDEWEB)

As metallic structures and devices are being created on a dimension comparable to the length scales of the underlying dislocation microstructures, the mechanical properties of them change drastically. Since such small structures are increasingly common in modern technologies, there is an emergent need to understand the critical roles of elasticity, plasticity, and fracture in small structures. Dislocation dynamics (DD) simulations, in which the dislocations are the simulated entities, offer a way to extend length scales beyond those of atomistic simulations and the results from DD simulations can be directly compared with the micromechanical tests. The primary objective of this research is to use 3-D DD simulations to study the plastic deformation of nano- and micro-scale materials and understand the correlation between dislocation motion, interactions and the mechanical response. Specifically, to identify what critical events (i.e., dislocation multiplication, cross-slip, storage, nucleation, junction and dipole formation, pinning etc.) determine the deformation response and how these change from bulk behavior as the system decreases in size and correlate and improve our current knowledge of bulk plasticity with the knowledge gained from the direct observations of small-scale plasticity. Our simulation results on single crystal micropillars and polycrystalline thin films can march the experiment results well and capture the essential features in small-scale plasticity. Furthermore, several simple and accurate models have been developed following our simulation results and can reasonably predict the plastic behavior of small scale materials.

Zhou, Caizhi

2010-12-15

118

Can sequential harvesting help small holder organic farmers meet consumer expectations for organic potatoes  

UK PubMed Central (United Kingdom)

The effectiveness of sequential harvesting in ensuring that potatoes produced by small-scale organic farmers in Embo, KwaZulu-Natal, South Africa, meet consumer quality expectations was investigated. A survey of organic and conventional potato consumers showed that absence of greening, sprouting and blemishes and a smooth skin texture were the criteria used by the consumers in selecting potatoes to purchase. Most consumers expected potatoes to store for three weeks post purchase. Based on consumer quality expectations, significantly higher quality losses were noted when potatoes were stored in a farmer’s store compared to sequential harvesting. After six weeks from crop maturity, sequential harvesting significantly reduced potato post harvest dormancy period but did not negatively affect sensory acceptability. Sequentially harvested potatoes met consumer quality and storage expectations. The practice provides resource-poor small-scale organic farmers with an efficient storage option where other methods and technologies may be inappropriate, ineffective or unaffordable.

Katundu Mangani; Hendriks Sheryl; Bower John; Siwela Muthulisi

2010-06-01

119

Relative risk for human illness of biogas effluent use in horticulture at small-scale pig farms in northern Vietnam  

DEFF Research Database (Denmark)

Treatment of animal manure in small-scale biogas systems are spreading rapidly in developing countries like Vietnam. The anaerobic fermentation breaks down solid matter and transforms it into methane which can be used for cooking and generation of light. Other benefits include a high-quality fertilizer effluent, reduction of problems with mal odour and a potential also to treat human waste products. Often the hygiene and health aspects of handling and digesting these organic wastes are unknown and the promotion of biogas technologies does rarely consider hygienic aspects. The aim of the current study was therefore to establish simple hygiene models for Vietnamese small-scale farmers that could describe the relative health risks associated with management of manure and consumption of the fertilized crop when using; i) fresh manure, ii) stored manure or iii) manure processed in the biogas plants. The hygiene models were developed based on information collected during interviews and observations of Vietnamese farmers operating biogas digesters as well as from the literature. Rather than calculating the specific risk for one person to become infected when handling a specific type of manure, we established hygiene models to calculate the relative risks of infection with the two model pathogens, Salmonella Typhimurium and Ascaris, allowing a comparison of risks for the different manure handling systems. Results showed that there was ten times higher risk of a human S. Typhimurium infection when handling fresh manure or composted manure as compared to handling of manure treated in a biogas system. In contrast, the risk for infection with the more resistant Ascaris was equivalent for all three manure handling systems. There is an urgent need to document the hygiene aspects of biogas systems developed and promoted to farmers in developing counties. Thus, further studies are needed on human exposure when handling animal manure and human excreta and pathogen survival in biogas systems as such information is essential to further refine the hygiene models developed and to formulate hygiene guidelines for biogas systems.

Kiilholma, Jenni; Stockmarr, Anders

2010-01-01

120

Application of improved management and nutrition technologies for small-holder dairy production and their adoption by farmers in developing countries  

International Nuclear Information System (INIS)

Full text: The objectives of this presentation are to consider some of the factors concerned in the application of technical change to small-scale dairying and the adoption of change by farmers. The presentation will consider (1) the motives of the small-scale dairy farmer, (2) the small-scale dairy farmer's own perceptions of his problems and needs, (3) how farmers deal with the two fundamental technologies implicit in dairy farming, feeding their animals and getting their cows in calf, and (4) dissemination routes most favoured by small scale dairy farmers. The geographical focus of the presentation is East Africa, a region associated with considerable progress and success in small-scale dairying (Kenya) as well as dairying projects in their early development (Tanzania). The concerns of small-scale farmers have been characterised; thus the farmers have multiple objectives, their households have low capacity to bear risk, their livestock enterprises are often integrated with cropping activities, and their livestock are often expected to be multi-functional. Some of the expected implications for small-scale dairy farmers are that: (1) inputs (including feed) are low and therefore milk yields are expected to be low; (2) inputs are often matched to output so that a reduction in milk price results in a reduction in concentrate allowance for the cows; (3) the use of time and cash are optimised, implying that priority will not be given to cattle if other farm enterprises seem financially more attractive. Perhaps not surprisingly, attitudes and systems vary within the farming community, allowing sub-groups of small-scale dairy farmers to be identified and defined. Thus some farmers emerge as more specialist or entrepreneurial than others, prepared to make greater investment in return for higher outputs. Attitudes and activities also differ according to location. Small-scale farmers close to urban centres may well have off-farm employment, diverting their attention from their cows. The problems faced by small-scale dairy farmers are diverse but some common threads emerge from a number of different studies. As well as the usual farmer concerns about the low prices received for their product and the high price of inputs, the availability of working capital appears to be a general anxiety. Poor feeding practices, partly consequent on weather but also a result of cash shortages, are widely recognised. Animal disease is also a general source of concern. It is clear from farmer consultations that farmers do respond to these problems with technical innovations appropriate to their resources. Often these innovations represent adaptations to the limited inputs available or affordable. Thus long inter calving intervals, probably a function of chronic under feeding as well as difficulties associated with bull availability, are countered by exploiting the long flat lactation curve associated with the failure of the cow to peak in early lactation as a result of the inadequate feeding. Cows are milked for many months, often with no intervening dry period between lactations. Although this maintains milk production, the production of replacement heifer calves is jeopardised by the long calving intervals, threatening the sustainability of small-scale dairying at both the household and national level. It follows from the above that small-scale dairy farmers have limited capacity for technical change. However, in some areas, the very adoption of small-scale dairying over the past few years is sufficiently novel to illustrate that its practitioners are prepared to adopt change if the proposals are considered feasible within the recognised constraints. Sometimes innovations fail to get to farmers because of inadequate extension services, although increasing access to the internet may signal rapid change in some regions. However, it is also clear that scepticism remains widespread. Recent studies indicate that, in some areas, extension services have limited success at disseminating innovation. Farmers' preferred sources of information are their chur

2002-01-01

 
 
 
 
121

Small Scale Testing of Core Fast Reactor Materials  

International Nuclear Information System (INIS)

The Fuel Cycle R and D (FCRD) initiative is investigating methods of burning minor actinides in a transmutation fuel. To achieve this goal, the fast reactor core materials (cladding and duct) must be able to withstand very high doses (>200 dpa design goal). While mechanical testing on large samples delivers direct engineering data these types of tests are only possible if enough sample material and required hot cell capabilities are available. Small scale materials testing methods in addition to large scale materials testing allows one to gain more insight on the same specimen and directly probe areas of interest which are not accessible otherwise (small welds, areas with different microstructure, etc.). However, in order to use small scale testing techniques and to probe materials microstructures using these methods, the relationship between the different scales needs to be investigated. In order to establish a research based relationship between small scale and large scale materials testing several different mechanical testing techniques were conducted on the same specimen irradiated in the Spallation Target Irradiation Program (STIP) at the Swiss spallation source (SINQ) at the Paul Scherrer Institute (PSI) up to a dose of 19 dpa. Tensile testing, micro hardness testing and micro compression testing on focused ion beam (FIB) manufactured pillars were performed on remaining parts of tensile test specimens tested and irradiated at PSI. It is shown that the yield strength increases measured by tensile testing, micro compression testing and micro hardness testing all show the same trend. In addition FIB based techniques also allow one to cut local electrode atom probe (LEAP) samples. In this procedure samples are cut of such a small size that no radioactivity on the prepared sample can be measured. In order to establish trust in these FIB based techniques estimations of residual activity on these samples is essential and presented here. (author)

2012-01-01

122

Small-Scale Combined Heat and Power Plants Using Biofuels  

Energy Technology Data Exchange (ETDEWEB)

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.

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

2002-11-01

123

Small scale production of biofuels: a feasibility assessment  

Energy Technology Data Exchange (ETDEWEB)

Current public policy fails to adequately address one of the most exigent concerns of the agricultural producer: the cost and availability of energy. Specifically, they are interested in energy production alternatives that are feasible and economic for implementation by smaller agricultural producers. After an extended review of much of the available popular and technical literature, as well as conducting interviews with numerous individuals knowledgeable in the field of alternative energy production, the Roosevelt-Custer Regional Council for Development has prepared this preliminary feasibility assessment on the small scale production of biofuels in North Dakota. The production of energy from renewable sources is not commerical; it is reality. Currently, North Dakotan's rely on energy produced from agricultural products to run their automobiles and to heat their homes, as well as to dry the crops on which much of the North Dakota economy depends. Over the next 20 years, this reliance on renewable energy sources is expected to triple. Unfortunately, most of the processes currently used to produce these biofuels are not adaptable for use by the smaller producer/consumer. Today, economics simply preclude the small scale production of biofuels. A deplorable consequence of this lag between demand and technical feasibility is the appearance of the quick-buck consultant. These individuals have not limited their activities to North Dakota but, in fact, they have appeared over the length and breadth of this nation. This report then is an assessment of the feasibility of producing biofuels in North Dakota by the small scale producer. Specific types of biofuels to be critiqued are: alcohol; vegetable oils; biogas/methane; and biomass briquettes.

Geyler, J.

1980-01-01

124

Small scale production of biofuels: a feasibility assessment  

Energy Technology Data Exchange (ETDEWEB)

Current public policy fails to adequately address one of the most exigent concerns of the agricultural producer: the cost and availability of energy. Specifically, they are interested in energy production alternatives that are feasible and economic for implementation by smaller agricultural producers. After a extended review of much of the available popular and technical literature, as well as conducting interviews with numerous individuals knowledgeable in the field of alternative energy production, the Roosevelt-Custer Regional Council for Development has prepared this preliminary feasibility assessment on the small scale production of biofuels in North Dakota. The production of energy from renewable sources is not chimerical; it is reality. Currently, North Dakotan's rely on energy produced from agricultural products to run their automobiles and to heat their homes, as well as to dry the crops on which much of the North Dakota economy depends. Over the next 20 years, this reliance on renewable energy sources is expected to triple. Unfortunately, most of the processes currently used to produce these biofuels are not adaptable for use by the smaller producer/consumer. Today, economics simply preclude the small scale production of biofuels. A deplorable consequence of this lag between demand and technical feasibility is the appearance of the quick-buck consultant. These individuals have not limited their activities to North Dakota but, in fact, they have appeared over the length and breadth of this Nation. This report then is an assessment of the feasibility of producing biofuels in North Dakota by the small scale producer. Specific types of biofuels to be critiqued are: alcohol; vegetable oils; biogas/methane; and biomass briquettes.

Geyler, J.

1980-01-01

125

Entirely renewable energy-based electricity supply system (small scale)  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a system comprising of a renewable source of energy and an energy storage device to smooth the power fluctuations. In order to investigate the performance of the system, an exact mathematical model for the system has been developed. Because of non-linearity of the mathematical model a computational method is used for performance investigation of the system. The objective of the paper is to present an entirely renewable energy based electricity supply system (small scale), to suggest the mathematical model of the system and computational method to analyze the performance of the system.

Zahedi, A. [Monash Univ., Caulfield (Australia). Div. of Electrical and Computer Systems Engineering

1997-12-31

126

Development of small scale soft x-ray lasers  

International Nuclear Information System (INIS)

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

1991-01-01

127

Small scale studies of production of fissium aerosols  

International Nuclear Information System (INIS)

[en] 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.)

1983-01-01

128

Optimal Tracking Controller Design for a Small Scale Helicopter  

CERN Multimedia

A model helicopter is more difficult to control than its full scale counterparts. This is due to its greater sensitivity to control inputs and disturbances as well as higher bandwidth of dynamics. This works is focused on designing practical tracking controller for a small scale helicopter following predefined trajectories. A tracking controller based on optimal control theory is synthesized as part of the development of an autonomous helicopter. Some issues in regards to control constraints are addressed. The weighting between state tracking performance and control power expenditure is analyzed. Overall performance of the control design is evaluated based on its time domain histories of trajectories as well as control inputs.

Budiyono, Agus

2008-01-01

129

Customer purchase criteria for small-scale cogeneration  

Energy Technology Data Exchange (ETDEWEB)

Utility customers follow a complicated process when deciding whether to undertake a cogeneration project. This report identifies key factors that motivate utility customers to invest or inhibit them from investing in small-scale (under 25 MW) cogeneration systems. The principal concerns facing prospective cogeneration decision makers were found to be: the amount of management time that must be devoted to first deciding whether to proceed with the project and then to implement it; system reliability and operational economics; future fuel prices and adequacy of supply; ownership arrangements and financing; and regulatory, legal, and contractual issues. 17 figs., 2 tabs.

Ciliano, R.E.; Steigelmann, W.H.; Williams, S.J. (RCG/Hagler, Bailly, Inc., Philadelphia, PA (United States))

1991-10-01

130

Efficient, small scale chemical oxygen-iodine laser  

Energy Technology Data Exchange (ETDEWEB)

More than 40% extractable power efficiency has been achieved in a transverse flow, small scale, chemically pumped iodine-atom laser. 5 W of cw laser emission at 1315 nm has been obtained via energy transfer from chemically generated O/sub 2/(/sup 1/..delta..) to I atoms in a 10 x 1 cm/sup 2/ rectangular flow duct. Simple construction materials, safely handled chemicals, and a medium size vacuum pump were used for fabricating and operating the laser. The importance of minimizing quenching of excited species by collision with water molecules or with the wall is demonstrated.

Bachar, J.; Rosenwaks, S.

1982-07-01

131

Small Scale Dairy Farming Practice in a Selective Area of Bangladesh  

Directory of Open Access Journals (Sweden)

Full Text Available The present study was assigned to determine the present status including general information, feeding breeding housing milking etc. and costs & returns of small dairy farms, to compare the productive and reproductive performance of crossbred and indigenous cows and to make recommendation for development of small scales dairy farm. With this view, the empirical data were collected by using protested questionnaire. The study was conducted at 8 thanas in Rangpur district, and four months-long survey was diminished on thirty small dairy owners. It appeared from the study that 57% farm owners belong to business class and remaining 43 per cent to different categories. Fifty three per cent took dairying as a side-business whereas only 47 per cent took it as a main business enterprise. Major percentage of farm owner education level that was Higher Secondary level (60%) and the average number of animal per farm was 13.01. The average monthly income of farm owners found in the study area was Tk. 4387. It was observed that farm owners had 85.4% crossbred (like Friesian cross and Jersey cross) and was 14.6% indigenous cattle, and 87% farmers used artificial insemination and rest used both artificial and natural services. Daily milk yield/cow/farm was 4.27 and 1.78 liters for a crossbred and indigenous dairy cow, respectively. It was estimated that the rearing cost of dairy cow was Tk. 67.5/cow/day and return from rearing dairy cow was Tk. 85.2/cow/day. The net return was Tk. 17.7/cow/day from crossbred in the study area and cost benefit ratio was 1: 1.26. The study showed that there were significant (P<0.01) differences within the dry period, service per conception, calving to first service, highest and lowest milk production and lactation period of crossbred and indigenous dairy cows. The study also showed non-significant differences within calving interval for crossbred and indigenous. Incase of small dairy farming, the farms were facing a lot of problems such as scarcity of feeds and fodder, high price of concentrate and lack of technical knowledge. Although the dairy cow owners face problems, the study observed that there were potentials particularly for the small dairy farmers. The small farmers by keeping 8-10 crossbred cows could earn a modest living by adopting small dairy farming as a profession.

M.M. Hossain; M.M. Hossain; M.M. Rashid; M. Asaduzzaman; M.M. Rahman

2005-01-01

132

Analysis of dryer performance for the improvement of small-scale litchi processing  

UK PubMed Central (United Kingdom)

Litchi is a significant cash crop in Thailand, but marketing is constrained by the perishable nature of the fruit. Drying can extend the shelf life of the fruit; however, in Thailand drying technology is still in its early stages of development. With the aim of improving locally available small-scale drying equipment, the performance of a litchi batch-dryer by a farmers' cooperative near Chiang Mai was studied. Drying conditions, energy consumption and product quality were monitored over three trials. Energy performance was analysed using instantaneous indices, leading to suggestions for possible design-modifications. About 29.8% of the heat input was used for moisture evaporation, 38.4% was lost via unsaturated exhaust air and 17.6% was lost to the ambient environment. An optimum air flow rate, one that minimises exhaust heat losses without increasing the drying time, was calculated. Temperature and air flow within the drying chamber varied, resulting in a non-uniform batch. To improve performance, a new design for the drying chamber air inlet is recommended.

Precoppe M; Nagle M; Janjai S; Mahayothee B; Müller J

2011-03-01

133

Small-scale magnetic field measurements in a sunspot  

Science.gov (United States)

We continue to study the fine peculiarities of the Zeeman effect in the sunspot of 25 March 1991 which was observed on horizontal solar telescope of Astronomical Observatory of Kyiv Shevchenko University. Zeeman splittings of I +V Stokes profiles of 20 spectral lines of FeI, VI, FeII, MoI, SiI, TiI and NiI were compared to diagnose the small-scale magnetic field structure in sunspot umbra. It was shown the observational evidences to the essential magnetic field inhomogeneity in both horizontal and vertical directions. First type of inhomogeneity follows from comparison of measured magnetic field values B versus Lande factors g of lines. Although the directly measured field strength B for the same place of sunspots was in range 150-650 mT, true range of field, as it follows from 'B-g' dependence, was likely wider, up to 1600 mT. Similar magnetic field strength was measured earlier by Lozitsky (1980, 1993, 1998) in solar flares and non-spot regions. In all cases such high magnetic field values should relate to the small-scale (spatiall unresolved) magnetic structures with small filling factor. Second type of inhomogeneity follows from magnetic field comparison for lines with the same or close Lande factors. This comparison shows that vertical magnetic field gradient at photospheric level of sunspot reaches about -0.8 mT/km.

Salimova, N.; Lozitsky, V.

2005-04-01

134

Development of the Small-Scale Shock Sensitivity Test (ssst)  

Science.gov (United States)

A small-scale test to measure shock sensitivity with less than a half gram of sample per test and six tests at most was developed. The goal is to screen new energetic compositions before the need for costly scale-up. The concept merged aspects of the Small-Scale Shock Reactivity Test (SSRT) developed at IHDIV, NSWC with those of standard gap tests. The SSRT measures the shock reactivity (explosiveness) of potentially energetic materials, often well-below critical diameter, without requiring a transition to detonation. Gap tests are used to gage shock sensitivity of explosives, but require a sample size large enough for steady detonation. The new test arrangement combined the shock-attenuating gap before the sample and the air gap after the sample found in gap tests with the small sample size and high confinement of the SSRT. The results for a plastic-bonded explosive formulated with either a regular or insensitive RDX confirmed the difference in sensitivities observed in traditional gap tests. Also, the results gave further confirmation to a two-part reaction mechanism for the insensitive RDX formulation.

Felts, J. E.; Sandusky, H. W.; Granholm, R. H.

2009-12-01

135

Innovative equipment for small-scale hydro developments  

Energy Technology Data Exchange (ETDEWEB)

Manufacturers of mechanical and electrical equipment for small-scale hydro developments have placed much emphasis in recent years on cost reductions obtainable through standardization and package units. More recently, the concept of using off-the-shelf design pumping equipment in the turbine mode is receiving increased attention in the industry. The results of a recently completed study undertaken to investigate the feasibility of using off-the-shelf pumps as turbines, with induction motors as generators, and other appropriate combinations of available equipment such as speed increasers, inlet valves, and gates for typical small-scale hydro installations are discussed. No actual tests were undertaken. However, a computer simulation model was developed in the study which provides a useful basis to estimate the performance of pumps in the turbine mode of operation. Detailed technical and economical investigations indicate that a major part of the small hydro plant potential can be economically covered by the use of pumps as turbines and induction motors as generators especially for the smaller ratings. The computer simulation model developed to predict turbine performance from pump performance curves is a useful tool for preliminary selection of suitable pumps. This is, however, not intended to be a tool or a substitute for model tests which need to be done by manufacturers when basic pump modifications are contemplated with the view to improve efficiency and performance when run as turbines. The investigations are a step in the right direction for the economical use of pumps as turbines in small hydro plants.

Lawrence, J.D.; Pereira, L.

1981-01-01

136

The case for small-scale domestic cannabis cultivation.  

Science.gov (United States)

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. PMID:20176465

Decorte, Tom

2010-02-21

137

The case for small-scale domestic cannabis cultivation.  

UK PubMed Central (United Kingdom)

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.

Decorte T

2010-07-01

138

Poverty in small-scale fisheries: The governance perspective  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract In fisheries, alleviating poverty sometimes requires strategies that are inherently in conflict. When aiming to develop a fishery as a means to reduce poverty, its common pool resource basis might be undermined, resulting in greater poverty. But poverty in fisheries is also linked to, or a part of deeper social issues and processes, for instance, the marginalization and exclusion of certain communities. Poverty also has many factors— income, health, literacy, gender, power, security, etc.—all of which make poverty alleviation a particularly “wicked problem” that would require a broad process of political, social and institutional reform. In other words, poverty alleviation is not only an issue of sustainable resource management but also one of societal governance. Drawing from research in small-scale fisheries communities in Nicaragua, Tanzania, and Bangladesh, this paper describes how fishing people cope with poverty. The paper discusses what the governance implications are for alleviating poverty at individual, household and community levels, and argue that both the definition of poverty and poverty alleviation in small-scale fisheries must be rooted in real life experiences.

Svein Jentoft; Paul Onyango; Mohammad Mahmudul Islam

2010-01-01

139

NONLINEAR SMALL-SCALE DYNAMOS AT LOW MAGNETIC PRANDTL NUMBERS  

International Nuclear Information System (INIS)

[en] Saturated small-scale dynamo solutions driven by isotropic non-helical turbulence are presented at low magnetic Prandtl numbers PrM down to 0.01. For PrM 1/2M down to values of 0.1. In agreement with earlier work, there is, in addition to a short Golitsyn k –11/3 spectrum near the resistive scale, also some evidence for a short k –1 spectrum on larger scales. The rms magnetic field strength of the small-scale dynamo is found to depend only weakly on the value of PrM and decreases by about a factor of two as PrM is decreased from 1 to 0.01. The possibility of dynamo action at PrM = 0.1 in the nonlinear regime is argued to be a consequence of a suppression of the bottleneck seen in the kinetic energy spectrum in the absence of a dynamo and, more generally, a suppression of kinetic energy near the dissipation wavenumber.

2011-11-10

140

The Small-Scale Dynamo at Low Magnetic Prandtl Numbers  

CERN Multimedia

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) \\propto l^{theta}, where v(l) is the eddy velocity at a scale l. We explore turbulent spectra ranging from incompressible Kolmogorov turbulence with theta = 1/3 to highly compressible Burgers turbulence with theta = 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...

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

2012-01-01

 
 
 
 
141

Profitability of Small-Scale Fisheries in Elmina, Ghana  

Directory of Open Access Journals (Sweden)

Full Text Available In order to achieve sustainable fishing livelihoods in coastal communities, data on profitability of small-scale fisheries relative to fish species caught and gear types used by fishermen is required as part of a broader fisheries management strategy. This study was undertaken with this in mind. Interviews were conducted among 60 fishermen between February and March 2010. Economic assessment of small-scale fishing activities were done using questionnaires based on direct market pricing and contingent valuation methods. The results indicate that highly profitable fish species include Epinephelus aeneus, Sparus caeruleostictus, Dentex angolensis and Lutjanus goreensis valued at US$2.97, US$2.87, US$2.85 and US$2.63 per kilogram respectively. The less profitable species include Dasyatis margarita, Caranx crysos and Sardinella aurita valued at US$0.34, US$0.66 and US$ 0.85 per kilogram respectively. Although Sardinella aurita was among the less valuable fish species, it was the main species driving profits for the fishermen due to its high share volume among the fish catches. Findings from this study suggest high rates of exploitation, in that stocks generally cannot provide for increased economic return in the face of increased investment. This is a clear indicator that the open-access nature of Ghanaian fisheries is not sustainable, and management reform is well overdue.

Denis W. Aheto; Noble K. Asare; Belinda Quaynor; Emmanuel Y. Tenkorang; Cephas Asare; Isaac Okyere

2012-01-01

142

Small-scale morphology across the surf zone  

Science.gov (United States)

Small-scale (< 5 m horizontal length) nearshore morphologic height variations were measured by combining CRAB surveys with bed elevations acquired with a 1 MHz sonic altimeter mounted on the CRAB during the October Phase of the DUCK94 experiment. Bedform plan views were recorded simultaneously using a 500 kHz side-scan sonar mounted on the CRAB. Waves and currents were measured at the same time. Significant temporal and spatial variations in the small-scale morphology were measured in response to changing waves and currents during the 2 weeks examined. Three cases are examined in detail: (1) mild waves and weak longshore currents resulting in wave ripples throughout the study area; (2) storm waves with strong longshore currents resulting in lunate and straight-crested mega-ripples in the trough of the barred beach; and (3) narrow-band, normally incident waves with a strong rip current resulting in a planar bed except in the throat of the rip where mega-ripples were measured. Wavenumber spectra of the bed were generally broad, indicating newly formed ripples coexisted with residual ripples from the past to form complex, multi-scaled ripple patterns.

Thornton, E. B.; Swayne, J. L.; Dingler, J. R.

1998-01-01

143

Small-scale AFBC hot air gas turbine power cycle  

Energy Technology Data Exchange (ETDEWEB)

The Energy and Environmental Research Corporation (EER), the Ohio Agricultural Research and Development Center (OARDC), the Will-Burt Company (W-B) and the US Department of Energy (DOE) have successfully developed and completed pilot plant tests on a small scale atmospheric fluidized bed combustion (AFBC) system. This system can be used to generate electricity, and/or hot water, steam. Following successful pilot plant operation, commercial demonstration will take place at Cedar Lane Farms (CLF), near Wooster, Ohio. The system demonstration will be completed by the end of 1995. The project is being funded through a cooperative effort between the DOE, EER, W-B, OARDC, CLF and the Ohio Coal Development Office (OCDO). The small scale AFBC, has no internal heat transfer surfaces in the fluid bed proper. Combining the combustor with a hot air gas turbine (HAGT) for electrical power generation, can give a relatively high overall system thermal efficiency. Using a novel method of recovering waste heat from the gas turbine, a gross heat rate of 13,500 Btu/kWhr ({approximately}25% efficiency) can be achieved for a small 1.5 MW{sub e} plant. A low technology industrial recuperation type gas turbine is used that operates with an inlet blade temperature of 1,450 F and a compression ratio of 3.9:1. The AFBC-HAGT technology can be used to generate power for remote rural communities to replace diesel generators, or can be used for small industrial co-generation applications.

Ashworth, R.A. [Energy and Environmental Research Corp., Orrville, OH (United States); Keener, H.M. [Ohio State Univ., Wooster, OH (United States). Ohio Agricultural Research and Development Center; Hall, A.W. [USDOE Morgantown Energy Technology Center, WV (United States)

1995-12-31

144

Coming to Grips with Farmers' variety Selection- the Case of New Improved Rice Varieties under Irrigation in South East Tanzania  

Directory of Open Access Journals (Sweden)

Full Text Available In collaboration with farmers, rice varieties were evaluated under small-scale irrigation in two villages of south east Tanzania for two consecutive cropping seasons (1999/2000 –2000/2001). The objectives were to give farmers access to new improved rice varieties; to identify the selection criteria farmers consider important in irrigated rice production; and to come to grips with their arguments. Farmers were provided with eleven improved varieties, which they compared with their own ones. Farmers' preferred varieties with short to medium maturity period, which produce many tillers and mature uniformly; and with long translucent aromatic grains for their own use and marketing. This study identified qualitative and quantitative evaluation criteria which farmers are using for selecting rice varieties. The implication for further research on rice in south east Tanzania is that the breeding programme should incorporate these attributes to address farmers' preferences, rather than to go for absolute maximum yield levels.

Kafiriti, EM.; Dondeyne, S.; Msomba, S.; Deckers, J.; Raes, D.

2003-01-01

145

Involvement of small-scale dairy farms in an industrial supply chain: when production standards meet farm diversity.  

Science.gov (United States)

In certain contexts, dairy firms are supplied by small-scale family farms. Firms provide a set of technical and economic recommendations meant to help farmers meet their requirements in terms of the quantity and quality of milk collected. This study analyzes how such recommendations may be adopted by studying six farms in Brazil. All farms are beneficiaries of the country's agrarian reforms, but they differ in terms of how they developed their activities, their resources and their milk collection objectives. First, we built a technical and economic benchmark farm based on recommendations from a dairy firm and farmer advisory institutions. Our analysis of the farms' practices and technical and economic results show that none of the farms in the sample apply all of the benchmark recommendations; however, all farms specialized in dairy production observe the main underlying principles with regard to feeding systems and breeding. The decisive factors in whether the benchmark is adopted and successfully implemented are (i) access to the supply chain when a farmer establishes his activity, (ii) a grasp of reproduction and forage production techniques and (iii) an understanding of dairy cattle feed dietary rationing principles. The technical problems observed in some cases impact the farms' dairy performance and cash position; this can lead to a process of disinvestment. This dynamic of farms facing production standards suggests that the diversity of specialized livestock farmers should be taken into account more effectively through advisory approaches that combine basic zootechnical training with assistance in planning farm activities over the short and medium term. PMID:22440036

Bernard, J; Le Gal, P Y; Triomphe, B; Hostiou, N; Moulin, C H

2011-05-01

146

Small-Scale Geothermal Power Plant Field Verification Projects: Preprint  

Energy Technology Data Exchange (ETDEWEB)

In the spring of 2000, the National Renewable Energy Laboratory issued a Request for Proposal for the construction of small-scale (300 kilowatt [kW] to 1 megawatt [MW]) geothermal power plants in the western United States. Five projects were selected for funding. Of these five, subcontracts have been completed for three, and preliminary design work is being conducted. The three projects currently under contract represent a variety of concepts and locations: a 1-MW evaporatively enhanced, air-cooled binary-cycle plant in Nevada; a 1-MW water-cooled Kalina-cycle plant in New Mexico; and a 750-kW low-temperature flash plant in Utah. All three also incorporate direct heating: onion dehydration, heating for a fish hatchery, and greenhouse heating, respectively. These projects are expected to begin operation between April 2002 and September 2003. In each case, detailed data on performance and costs will be taken over a 3-year period.

Kutscher, C.

2001-07-03

147

Small Scale Industries and Economic Development: Special Reference to India  

Directory of Open Access Journals (Sweden)

Full Text Available The small scale industries sector contributes significantly to the manufacturing output, employment and exports of the country. It is estimated that in terms of value, the sector accounts for about 45 per cent of the manufacturing output and 40 per cent of the total exports of the country. The sector is estimated to employ about 59 million persons in over 26 million units throughout the country. The production of SSI unit in India was Rs 84,413 crore in 1992-93, which increased and reached up to Rs. 9,82919 crore in 2009-10. The production of SSI units shows continually raising trend during the study period. During 1992-93 SSI units shows 4.71 growth rate in production which gone up to 11.59 percent in 2009-10.

Dr. S. N. Babar

2012-01-01

148

Numerical Simulation and Optimazation of Small Scale LNG Plant  

Science.gov (United States)

The LNG20 is a small-scale natural gas liquefier. Its capacity is 20 cube meters LNG per day. This liquefier could be used for the pipeline gas, coalbed gas, oil field gas liquefaction and peakshaving plant for town gas gate station and natural gas power plant. Two processing cycles are applied to LNG20, nitrogen expander cycle and mixed refrigerant cycle. In this report, two feed gases are the target sources; one is the pipeline gas in ``West-to-east pipeline gas'' in a gate station in Zhejiang province and coalbed gas in Northeast China. The numerical simulation and optimization for the LNG20 were carried out to obtain the design parameters.

Li, H. Y.; Jia, L. X.; Fan, Q. H.; Yin, Q. S.

2006-04-01

149

Exergoeconomic analysis of small-scale biomass steam cogeneration  

Energy Technology Data Exchange (ETDEWEB)

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)

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

150

Small-Scale Shock Reactivity and Internal Blast Test  

Science.gov (United States)

Explosives react from a strong shock, even in quantities too small for detonation. The potential for a new material to be an explosive can be evaluated from this shock reactivity. The recently developed small-scale shock reactivity test (SSRT) uses very high confinement to allow prompt reactions to occur in less than half-gram samples well below critical diameter. Early and late-time reactions are simultaneously measured from a single sample subjected to the output from an RP-80 detonator. Prompt reactions are quantified by a dent in a soft aluminum witness block, while later reactions, such as from fuel/air combustion, are measured by recording blast pressure. Internal blast quasi-static pressure is obtained by confining the sample apparatus within a three-liter chamber. Late-time reaction effects of plastics, and results from HMX, HMX/Aluminum, and a plastic-bonded explosive (PBX) are reported.

Granholm, R. H.; Sandusky, H. W.

2006-07-01

151

Small-Scale Performance Testing for Studying New Explosives  

Energy Technology Data Exchange (ETDEWEB)

The development of new high-explosive (HE) formulations involves characterizing their safety and performance. Small-scale experiments requiring only a small amount of explosives are of interest because they can facilitate development while minimizing hazards and reducing cost. A detonation-spreading, dent test, called the Floret test, was designed to obtain performance data for new explosives. It utilizes the detonation of about a 1.0 g sample of HE, initiated by an accelerated aluminum flyer. Upon impact, the HE sample detonates and a copper witness plate absorbs the ensuing shock wave. The dent of the plate is then measured and correlated to the energetic output of the HE. Additionally, the dent measurement can be used to compare the performance of different explosives. The Floret test is beneficial because it quickly returns important performance information, while requiring only a small explosive sample. This work will explain the Floret test and discuss some exemplary results.

Gagliardi, F J; Chambers, R D; Tran, T D

2005-04-29

152

Small-scale isolation of synaptic vesicles from mammalian brain.  

UK PubMed Central (United Kingdom)

Synaptic vesicles (SVs) are essential organelles that participate in the release of neurotransmitters from a neuron. Biochemical analysis of purified SVs was instrumental in the identification of proteins involved in exocytotic membrane fusion and neurotransmitter uptake. Although numerous protocols have been published detailing the isolation of SVs from the brain, those that give the highest-purity vesicles often have low yields. Here we describe a protocol for the small-scale isolation of SVs from mouse and rat brain. The procedure relies on standard fractionation techniques, including differential centrifugation, rate-zonal centrifugation and size-exclusion chromatography, but it has been optimized for minimal vesicle loss while maintaining a high degree of purity. The protocol can be completed in less than 1 d and allows the recovery of ?150 ?g of vesicle protein from a single mouse brain, thus allowing vesicle isolation from transgenic mice.

Ahmed S; Holt M; Riedel D; Jahn R

2013-05-01

153

Minimal Length and Small Scale Structure of Spacetime  

CERN Document Server

Many generic arguments support the existence of a minimum spacetime interval L_0. Such a "zero-point" length can be naturally introduced in a locally Lorentz invariant manner via Synge's world function bi-scalar \\Omega(p,P) which measures squared geodesic interval between spacetime events p and P. I show that there exists a \\emph{non-local} deformation of spacetime geometry given by a \\emph{disformal} coupling of metric to the bi-scalar \\Omega(p,P), which yields a geodesic interval of L_0 in the limit p -> P. Locality is recovered when \\Omega(p,P) >> L_0^2/2. I discuss several conceptual implications of the resultant small-scale structure of spacetime for QFT propagators as well as spacetime singularities.

Kothawala, Dawood

2013-01-01

154

Externally fired gas turbine cycles for small scale biomass cogeneration  

Energy Technology Data Exchange (ETDEWEB)

In this conceptual study, externally fired gas turbine cycles in combination with a biomass-fueled, atmospheric circulating fluidized bed (CFB) furnace are investigated for small scale heat and power production ({approximately} 8 MW fuel input). Three cycle configurations are considered: closed cycle, with nitrogen, helium, and a helium/carbon dioxide mixture as working fluids; open cycle operating in parallel to the CFB system; and open cycle with a series connection to the CFB system. Intercooling, postcooling, and recuperation are employed with the goal of maximizing power output. Aside from a thermodynamic performance analysis, the study also includes an evaluation of the turbomachinery characteristics. Simulation results show that thermodynamic performance varies slightly between the different configurations, with electrical efficiencies approaching 38% (LHV) and power-to-heat ratios as high as 0.80. Equipment size is found to depend primarily upon the type of working fluid.

Anheden, M.; Ahlroth, M.; Martin, A.R.; Svedberg, G.

1999-07-01

155

A multi scale model for small scale plasticity  

International Nuclear Information System (INIS)

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

2002-01-01

156

Concept for integrity assurance of small scale piping systems  

International Nuclear Information System (INIS)

There may be safety and economic reasons which make it absolutely necessary that the integrity of small-scale piping systems be guaranteed. This might be problematic considering experience to date. Analysing the damages detected it has been possible to assign these to systems and operational modes. They are primarily due to the insufficient design, which in turn is connected to the low safety relevance assumed for these systems. Determination of the degradation mechanisms and the causes give sufficient information for preventing further damage of this kind. Non-allowable dynamic loads as well as quick crack growth caused by corrosion are to be avoided by taking the proper action. Even if the measures taken may be different from plant to plant or component to component, it is possible to state a generally applicable systematic approach to guarantee integrity. (orig.).

1996-01-01

157

Numerical simulation of small scale soft impact tests  

International Nuclear Information System (INIS)

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)

2008-01-01

158

First Principle Approach to Modeling of Small Scale Helicopter  

CERN Multimedia

The establishment of global helicopter linear model is very precious and useful for the design of the linear control laws, since it is never afforded in the published literatures. In the first principle approach, the mathematical model was developed using basic helicopter theory accounting for particular characteristic of the miniature helicopter. No formal system identification procedures are required for the proposed model structure. The relevant published literatures however did not present the linear models required for the design of linear control laws. The paper presents a step by step development of linear model for small scale helicopter based on first-principle approach. Beyond the previous work in literatures, the calculation of the stability derivatives is presented in detail. A computer program is used to solve the equilibrium conditions and then calculate the change in aerodynamics forces and moments due to the change in each degree of freedom and control input. The detail derivation allows the c...

Budiyono, A; Lesmana, H

2008-01-01

159

Biomass energy use in small-scale commercial operations  

Energy Technology Data Exchange (ETDEWEB)

A coffee roasting system using sawdust has been developed by Carbon Cycle, a California Company. They have shown that biomass combustion can be a safe, low-cost alternative to the use of natural gas in a food processing operation. Two systems are in operation with a combined run time of over 80,000 hours. The system uses a patented furnace technology characterized by thermal control to clean combustion, which, when used with biomass, achieves an even, slow roast of raw coffee beans. This results in high-quality coffee flavor. The technology has potential for use in other medium-temperature applications in food processing, district heating, and small-scale energy production. (author)

Sachs, K.M. [Carbon Cycle Co., Woodland, CA (United States)

1999-07-01

160

Rural electrification in Malaysia via small scale biomass gasifier  

International Nuclear Information System (INIS)

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)

2000-01-01

 
 
 
 
161

Farmers’ perceptions of pollinators’ importance in coffee production in Uganda  

Directory of Open Access Journals (Sweden)

Full Text Available Coffee (Coffea canephora) is the principal cash crop and the country’s largest agricultural foreign revenue earner in Uganda. Previous surveys confirmed that coffee grown in central Uganda was largely depending on bee pollination to set fruit set. Despite its high contribution to the economics of agricultural sector in Uganda and despite its great dependency to bees for fruit set, it is not clear if small-scale farmers are aware of the importance of managing farm-landscapes for pollination services conservation to increase coffee yield. The aim of this study was to assess farmers’ perceptions and knowledge of the importance of pollinators and pollination services conservation for coffee production enhancement. The main hypothesis was that small-scale coffee growers were not aware of the relevance of pollination services for coffee production. Farmers’ surveys were conducted in coffee-banana farming systems in central Uganda. It was found in this study that more than 90% of interviewed farmers were not aware of the role played by bees in coffee yield increase. Farmers were not willing to manage their lands to protect pollination services, particularly because they considered pollination service as an unsolicited “free service”, or as a “public good”. Farmers were not aware of the role of semi- natural habitats serving as reservoir (hiding points) for pollinators in the surrounding of coffee fields. However, they were aware of some ecosystem services delivered in the coffee- banana farming system such as planting shading trees. Only 3.3% of respondents believed that placing beehives in coffee farms could increase the yield. The study recommended the increase of the awareness of small-scale coffee growers on the importance of pollinators to increase coffee production. It is recommended that future management of pollination services are built on improving farmers’ indigenous knowledge and on adequate understanding of the ecology of the local pollinator species. There is a need to broadly scale-up best field, habitat and landscape management strategies and practices that are friendly to coffee pollinators in rural landscapes of Uganda

Théodore Munyuli

2011-01-01

162

A review of a public private extension partnership for small-scale sugarcane farmers in South Africa  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The main objective of APPRI Workshop was to analyse conditions for implementing alternative action-research practices in partnership for development, taking into account the difficulties of "official" research and of the rural world, faced with the major challenges of sustainable development in the ...

Eweg, Matin

163

TROPICAL MAIZE SYNTHETICS BREEDING IN MOISTURE-STRESS TOLERANCE FOR SMALL-SCALE FARMERS IN BRAZILIAN SEMI ARID REGIONS  

Directory of Open Access Journals (Sweden)

Full Text Available The objective of this work was to evaluate 144 S2 progenies from each of two synthetic maize populations, Syndent and Synflint, from a breeding program for drought tolerance, to obtain synthetics with high yield potential and good agronomic performance in the semi-arid regions in Brazil. The 288 S2 progenies from the two synthetics were evaluated using a 12 x 12 lattice design with two replications in two conditions with water stress (WS) and non water stress (NS) in Janaúba, MG, Brazil, in 2000. The combining analysis of variance showed highly significant (P<0.01) effects in environments and progenies and their interaction for Synflint, and significant ones (P<0.05) in the interaction for Syndent. The estimates of the broad sense heritability of ear yield were: Synflint h2 = 0.382 and 0.752 for WS and NS, respectively; Syndent h2 = 0.607 and 0.635 for WS and NS, respectively. The genetic variance estimates were greater in NS than in WS environments. The error variance estimates were the greatest in WS x NS interaction for the two synthetics. The predicted responses to selection pointed out better gains for yield when selection is performed in NS rather than WS environments. Substantial variability exists in these two synthetics for drought tolerance and its characteristics, indicating that there is an opportunity for improving their tolerance via recurrent selection.

ELTO EUGENIO GOMES E GAMA; SIDNEY NETTO PARENTONI; FREDERICO OZANAN MACHADO DURÃES; CARLOS EDUARDO PRADO LEITE; MANOEL XAVIER DOS SANTOS; CLESO ANTÔNIO PATTO PACHECO; ANTÔNIO CARLOS DE OLIVEIRA

2004-01-01

164

Certification as an upgrading strategy for small-scale farmers and their cooperatives : a value chain analysis for Nicaraguan coffee  

Digital Repository Infrastructure Vision for European Research (DRIVER)

For many small producers in developing countries coffee is a major income source. However, the coffee market is characterized by high price volatility and increased power concentration among buyers in consuming countries. Due to the very low international coffee prices during the recent coffee crisi...

Kiemen, Anna; Beuchelt, Tina

165

The role of statutory and local rules in allocating water between large- and small-scale irrigators in an African river catchment  

Scientific Electronic Library Online (English)

Full Text Available Abstract in english This paper presents a case study of large- and small-scale irrigators negotiating for access to water from Nduruma River in the Pangani River Basin, Tanzania. The paper shows that despite the existence of a formal statutory water permit system, all users need to conform to the existing local rules in order to secure access to water. The spatial geography of Nduruma is such that smallholder farmers are located upstream and downstream, while large-scale irrigators are in th (more) e midstream part of the sub-catchment. There is not enough water in the river to satisfy all demands. The majority of the smallholder farmers currently access water under local arrangements, but large-scale irrigators have obtained state-issued water use permits. To access water the estates adopt a variety of strategies: they try to claim water access by adhering to state water law; they engage with the downstream smallholder farmers and negotiate rotational allocation; and/or they band with downstream farmers to secure more water from upstream farmers. Estates that were successful in securing their water access were those that engaged with the local system and negotiated a fair rotational water-sharing arrangement. By adopting this strategy, the estates not only avoid conflict with the poor downstream farmers but also gain social reputation, increasing chances of cooperative behaviours from the farmers towards their hydraulic infrastructure investments. Cooperative behaviours by the estates may also be due to their dependence on local labour. We further find diverging perspectives on the implementation of the state water use permits - not only between the local and state forms of water governance, but also between the differing administrative levels of government. The local governments are more likely to spend their limited resources on 'keeping the peace'; rather than on enforcing the water law. At the larger catchment scale, however, the anonymity between users makes it more difficult to initiate and maintain cooperative arrangements.

Komakech, Hans C; Condon, Madison; van der Zaag, Pieter

2012-01-01

166

Robust, small-scale cultivation platform for Streptomyces coelicolor  

DEFF Research Database (Denmark)

ABSTRACT: BACKGROUND: For fermentation process and strain improvement, where one wants to screen a large number of conditions and strains, robust and scalable high-throughput cultivation systems are crucial. Often, the time lag between bench-scale cultivations to production largely depends on approximate estimation of scalable physiological traits. Microtiter plate (MTP) based screening platforms have lately become an attractive alternative to shake flasks mainly because of the ease of automation. However, there are very few reports on applications for filamentous organisms; as well as efforts towards systematic validation of physiological behavior compared to larger scale are sparse. Moreover, available small-scale screening approaches are typically constrained by evaluating only an end point snapshot of phenotypes. RESULTS: To address these issues, we devised a robust, small-scale cultivation platform in the form of MTPs (24-square deepwell) for the filamentous bacterium Streptomyces coelicolor and comparedits performance to that of shake flasks and bench-scale reactors. We observed that re-designing of medium and inoculum preparation recipes resulted in improved reproducibility. Process turnaround time was significantly reduced due to the reduction in number of unit operations from inoculum to cultivation. The incorporation of glass beads (ø 3 mm) in MTPs not only improved the process performance in terms of improved oxygen transfer improving secondary metabolite production, but also helped to transform morphology from pellet to disperse, resulting in enhanced reproducibility. Addition of MOPS into the medium resulted in pH maintenance above 6.50, a crucial parameter towards reproducibility. Moreover, the entire trajectory of the process was analyzed for compatibility with bench-scale reactors. 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 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 filamentous bacteria and the use may significantly reduce the workload and costs.

Sohoni, Sujata Vijay; Bapat, Prashant Madhusudan

2012-01-01

167

Internal dosimetry. Macroscopic, small-scale and microscopic perspectives  

Energy Technology Data Exchange (ETDEWEB)

Internal dosimetry deals with the assessment of absorbed dose for radionuclides distributed inside the body. The absorbed dose is in its turn used for correlation with the biological effect caused by the irradiation. In radioimmunotherapy is however the correlation not easily found and factors influencing this are evaluated and discussed in this work. The internal dosimetry could be subdivided into three levels; macroscopic, small-scale, and microscopic dosimetry. Macroscopic dosimetry: The MIRD S formalism is used to assess the mean absorbed dose to normal organs and tissues. The activity distribution is assumed to be uniform and the calculated mean absorbed dose serves as a good representation of the absorbed dose since the volumes are large compared to the range of emitted particles. The mean absorbed dose to normal organs and tumours was determined for B-cell lymphoma patients undergoing radioimmunotherapy with {sup 90}Y-hLL2 (Paper I). The absorbed dose to bone marrow, which is the most radiation sensitive tissue in the body, could be calculated via a method based on the activity in blood samples. The ratio of the activity concentration in bone marrow to the activity concentration in blood was, however, found not to be constant over time. A method for taking this into account in the calculations was proposed (Paper II). Lymphomas are in general radiation sensitive, fast-responding tumours. A decrease in the mass of a tumour during the course of radioimmunotherapy could have a strong influence on the calculated absorbed dose and a method for correction due to this effect was developed (Paper III). Small-scale dosimetry: The MIRD formalism is used, but as the volume is smaller, the mean absorbed dose serves as a poorer representation of the absorbed dose. A model of the anatomy of a mouse was developed and the influence on the S values (absorbed dose per decay) for the choice of organ mass, shape of the organs and distances between the organs was investigated (Paper IV). The average number of atoms per tumour cell was determined from blood samples from a patient having a B cell lymphoma. The MIRD cellular S values were used for calculation of the mean absorbed dose to a cell (Paper V). Internal microdosimetry: The absorbed dose is the expectation value of the specific energy, which is a quantity that takes stochastic effects of the energy depositions into account. The smaller a volume, the larger stochastic effects are seen. Lymphoma patients could have a leukaemic spread of their disease and as {sup 90}Y often is used for therapy, the treatment to the single tumour cells is not optimized. Theoretical calculations were performed based on experimental data for an evaluation (Paper VI)

Hindorf, Cecilia

2004-03-01

168

AFBC-HAGT, an efficient small scale power plant  

Energy Technology Data Exchange (ETDEWEB)

A team comprised of the Energy and Environmental Research Corporation (EER), the Will-Burt Company, and the Ohio Agricultural Research and Development Center (OARDC) designed installed and tested a pilot scale atmospheric fluidized (bubbling) bed combustion (AFBC) system to heat hot water. Following testing, a commercial prototype unit was installed at Cedar Lane Farms (CLF), near Wooster, Ohio. The unit was started up in January, 1995, and is currently in operation. It provides hot water for greenhouse heating, requiring about two hours per day of operator attention. The development was funded by the Ohio Coal Development Office, the U.S. Department of Energy, and the team members. Based on the success of the prototype operation a commercial size unit was recently designed for hot water heating use. This small scale AFBC system can be designed not only to produce hot water or steam but also to efficiently generate electricity (60 kWe to 3.5 MWe size range). Most small scale fluidized bed systems use in-bed heat transfer tubes to generate saturated steam which can then be superheated and fed to a steam turbine for electrical power generation. This AFBC has no internal heat transfer surfaces. It can be combined with an air heater that is integrated with a recuperated Hot Air Gas Turbine (HAGT), to yield a more efficient power plant than that possible with small steam plants of comparable size that have optimal gross efficiencies of about 12% (29,060 Btu/kWhr). Depending on ambient air temperature, this AFBC-HAGT power cycle can reach efficiencies of 28% without auxiliary diesel fuel oil firing. The system is ideally suited for rural communities that are not tied into an electric power grid. It is low tech, easy to operate, provides approximately double the efficiency of small steam cycle power plants, and can be used in areas where water is scarce. When firing local coal and/or bio-mass it can be very cost effective compared to diesel power generation.

Ashworth, R.A. [Energy and Environmental Research Corp., Orrville, OH (United States); Webner, R.L. [Will-Burt Company, Orrville, OH (United States); Keener, H.M. [Ohio State Univ., Wooster, OH (United States). Ohio Agricultural Research and Development Center

1997-12-31

169

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

DEFF Research Database (Denmark)

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 much less in Eastern and Southern Africa and the increase in production was mainly a result of expansion of land under cultivation and the number of producers, rather than of improved productivity (e.g. Poulton et al., 2004; Delpeuch and Vandeplas, 2011). Organic production methods could be an attractive option for cotton farmers in Eastern Africa, because in this region, the use of chemical inputs is anyway virtually absent, the labor cost is low, and organic cotton has a higher sales price than conventional cotton. In order to scrutinize this option, we use microeconomic production theory and stochastic frontier models to thoroughly analyze organic cotton production in Tanzania. Our study is based on a unique data set of 180 small-scale organic cotton farmers in the Meatu region in Tanzania. This data set does not only provide information on input and output quantities, prices of traded inputs 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, and competitiveness. Traditionally, the measurement of allocative efficiency assumed that all inputs can be freely traded at a given price on a perfectly functioning market. This assumption was relaxed by Tauer (1993) who suggested an approach that can additionally account for quasi-fixed input quantities, which 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, these inputs face non-constant shadow prices, which are determined by their opportunity costs. In order to account for the endogeneity of these shadow prices when calculating allocative efficiencies, we use the approach for modeling imperfect markets developed by Henning and Henningsen (2007). Based on our results, we can evaluate the current situation of organic cotton production as well as the potential and the directions for improving its profitability and competitiveness. Unfortunately, we did not finish the empirical analysis before the submission deadline. However, we will definitely include the results in our presentation at the conference.

Mgeni, Dotto; Henningsen, Arne

170

Tools for mining. Techniques and processes for small scale mining  

Energy Technology Data Exchange (ETDEWEB)

The handbook serves as an information source of planning and consultancy aid for technicians, engineers and advisors for small-scale mining in developing countries. It integrates both modern, historical and traditional techniques for approaches to solutions, thus providing multifarious possibilities for solving present-day problems. Included in the handbook are techniques taken from the most varied sectors of mining operations. In the part of the handbook devoted to techniques, special attention is paid to ensuring local production in developing countries, to offering environmentally-friendly technologies and to taking into account the social and cultural framework conditions of the miners when selecting the techniques. Following plots are contained: Analysis: Problem areas and units for taking samples, examination and necessary investigation, individual techniques. Underground mining: With suggestion for organisation of work environmental and health aspects, safety techniques, weathering, mine drainage, extension, lighting, extraction, loading haulage and mine transport. Open cast mining: Hints for environmental and health aspects, rocks and clay minings, techniques from the subchapters of strip mining equipment and special techniques. Mineral processing: Hints for organising work and technical procedures for diamond processing, gold processing and the processing of phosphate raw materials to fertilizers, approaches for optimising the organisation of work and techniques from the sub-chapters of comminution, classification, gravimetric sorting, gold processing, special techniques for processing, drying and purification. Mechanisation and power supply: power transformation and distribution, mechanisation, environmental and health aspects and the most varied techniques of supplying power. (orig./MSK)

Priester, M.; Hentschel, T.; Benthin, B.

1993-01-01

171

Small-scale clad-effects study. [PWR; BWR  

Energy Technology Data Exchange (ETDEWEB)

The Small-Scale Clad Effects Study of the HSST Program was initiated to study the interaction of stainless cladding with flaws initiated in and propagating in base metal. From the designer's viewpoint stainless cladding is primarily viewed as a corrosion- and crud-prevention measure in light-water reactor vessel design, and except for its effect upon fatigue in thermal transients, its effect upon structural integrity has heretofore been largely disregarded. With the more recent focus of safety studies upon LOCA scenarios that emphasize the behavior of small flaws, it has become evident that stainless cladding may have a key role in the propagation and/or arrest of propagating flaws. A complicating factor in understanding the role of stainless cladding in this setting is its fracture toughness as a function of radiation dose and as a function of fabrication process for which meager data exist. The initial phase of this study has attempted to address this question by testing stainless-clad specimens that had been subjected to heat treatments to simulate beginning-of-life and end-of-life toughness conditions to fast-running cracks.

Robinson, G.C.

1982-01-01

172

Advanced conversion technologies for small-scale remote power systems  

Energy Technology Data Exchange (ETDEWEB)

Forest fires that endangered remote US Air Force sites equipped with radioisotope thermoelectric generators (RTGs) prompted the assessment of power generating systems that could be substituted for RTGs in small scale (10--120 watt) applications. Other non-RTG sites were also studied during the assessment. The power system assessment was conducted by the US Air Forces` Wright Laboratory and included the evaluation of engine-driven generators, solar, wind generators, propane thermoelectric generators (TEGs), batteries, fuel cells, and power systems based on advanced conversion technologies; such as, thermionics, free piston Stirling Engines (FPSE), alkali metal thermoelectric conversion (AMTEC), and thermophotovoltaics (TPV). The assessment team concluded that continued use of the RTGs is clearly the safest, most reliable, and most economical approach to supplying electrical power for remote, difficult to access locations. If political considerations force the replacement of the RTGs, the likely replacement is a hybrid system consisting of solar-PV with a propane-TEG for off-solar times. The transport of combustible fuels in Arctic environments is extremely expensive. It is this high logistics cost that signaled the need to consider the option of more efficient and cost effective power sources for the remote, Arctic applications. This paper summarizes the assessment of some of the more attractive power systems that are based on the advanced conversion technologies of AMTEC, TPV and FPSE.

Lamp, T.R. [Wright Lab., Wright-Patterson AFB, OH (United States)

1996-12-31

173

Small-scale electric generators for arctic applications  

Energy Technology Data Exchange (ETDEWEB)

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 {ital American} {ital Institute} {ital of} {ital Physics}

Lamp, T.R. [Aero Propulsion and Power Directorate, Wright Laboratory, Wright Patterson AFB, Ohio 45433-7251 (United States)

1995-01-20

174

Studying the small scale ISM structure with supernovae  

CERN Multimedia

AIMS. In this work we explore the possibility of using the fast expansion of a Type Ia supernova photosphere to detect extra-galactic ISM column density variations on spatial scales of ~100 AU on time scales of a few months. METHODS. We constructed a simple model which describes the expansion of the photodisk and the effects of a patchy interstellar cloud on the observed equivalent width of Na I D lines. Using this model we derived the behavior of the equivalent width as a function of time, spatial scale and amplitude of the column density fluctuations. RESULTS. The calculations show that isolated, small (<100 AU) clouds with Na I column densities exceeding a few 10^11 cm^-2 would be easily detected. In contrast, the effects of a more realistic, patchy ISM become measurable in a fraction of cases, and for peak-to-peak variations larger than ~10^12 cm^-2 on a scale of 1000 AU. CONCLUSIONS. The proposed technique provides a unique way to probe the extra-galactic small scale structure, which is out of reach f...

Patat, F; Parrent, J; Branch, D

2010-01-01

175

Velocities measured in small scale solar magnetic elements  

CERN Multimedia

We have obtained high resolution spectrograms of small scale magnetic structures with the Swedish 1-m Solar Telescope. We present Doppler measurements at $0\\farcs{2}$ spatial resolution of bright points, ribbons and flowers and their immediate surroundings, in the C {\\small{I}} 5380.3 {\\AA} line (formed in the deep photosphere) and the two Fe {\\small{I}} lines at 5379.6 {\\AA} and 5386.3 {\\AA}. The velocity inside the flowers and ribbons are measured to be almost zero, while we observe downflows at the edges. These downflows are increasing with decreasing height. We also analyze realistic magneto-convective simulations to obtain a better understanding of the interpretation of the observed signal. We calculate how the Doppler signal depends on the velocity field in various structures. Both the smearing effect of the non-negligible width of this velocity response function along the line of sight and of the smearing from the telescope and atmospheric point spread function are discussed. These studies lead us to t...

Langangen, O; van der Voort, L R; Stein, R F; Carlsson, Mats; Voort, Luc Rouppe van der

2006-01-01

176

Small-scale inviscid accretion discs around black holes  

CERN Document Server

Gas falling quasi-spherically onto a Schwarzschild black hole can form an inner thin accretion disc if its specific angular momentum, $l$, exceeds $\\lmin\\approx 0.75r_gc$, where $r_g$ is the Schwarzschild radius. The standard disc model assumes $l\\gg\\lmin$. We argue that in many black-hole sources the accretion flows can have $l\\simgt\\lmin$, and assess the mechanism of accretion in this regime. In a range $\\lminsmall-scale disc forms in which gas overcomes the centrifugal barrier and spirals fast into the black hole without any help of horizontal viscous stresses. Such an ``inviscid'' disc, however, interacts inelastically with the infall feeding the disc, which leads to energy dissipation. This interaction determines the disc dynamics and luminosity. We find the radiative efficiency of this accretion regime to be comparable with the efficiency of the standard disc. The maximum radius of the fast inviscid disc is $r_{\\rm max}\\approx 2\\lcr^2/r_gc^2\\sim 14 r_g$, and the energy release peaks at...

Beloborodov, A M; Beloborodov, Andrei M.; Illarionov, Andrei F.

2000-01-01

177

Capital cost of small-scale tidal power plants  

Energy Technology Data Exchange (ETDEWEB)

A generic methodology is devised for estimating the capital costs of small-scale tidal power plants (1-100 MW rated power). In addition to the general dimensions determining the size of the tidal pond resource (surface area and tidal range) two site-specific dimensions (depth and length of closure structure) are required for this estimate. Dimensionless parameters and variables describing the power plant performance are used in the cost analysis to specify the relative sizes of the power plant components (turbine-generator, power house, sluice gates, cofferdam, and barrage). The generic cost estimates are compared with those used in several site-specific studies. Unit total capital cost (cost per unit of average power produced) is calculated as a function of the size of the tidal pond resource, the latter being measured in terms of the ideal tidal pond power. A range of closure depths and lengths was used in these generic cost estimates. The minimum unit capital cost is shown to depend upon the size of the tidal pond as well as the site-specific dimensions. An optimum turbogenerator size can be determined to minimize the capital cost.

Fay, J.A.; Smachio, M.A.

1983-11-01

178

Numerical simulation of a small-scale biomass boiler  

International Nuclear Information System (INIS)

[en] 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.

2012-01-01

179

An exergy analysis of small scale LNG processes  

Energy Technology Data Exchange (ETDEWEB)

This presentation evaluated the following 4 processes for producing small-scale liquefied natural gas (LNG): a single-stage mixed refrigerant process; a two-stage expander nitrogen refrigerant; and, two open loop turbo expander processes. Each process was evaluated in terms of energy costs and suitability for an offshore production facility. The Commercial software and the Peng-Robinson Equation of State thermodynamic package were used to simulate all processes. An exergy analysis was performed in two stages for each process. The first involved the analysis of composite curves for the feed and recycle streams compared to the refrigerant or cold recycle stream. The degree of optimization available to each process was illustrated and information on the relative size of the LNG exchanger was provided. The second stage involved a full exergy analysis of each process. The relative contributions to the total shaft work requirements were demonstrated. The main factor responsible for the reduced efficiencies of the expander process was the lower efficiencies of the turbo expander driven compressors. It was suggested that a nitrogen process is the preferred option for producing LNG at offshore facilities.

Remeljej, C.W. [BHP Billiton, Melbourne (Australia); Hoadley, A.F.A. [Monash Univ., Victoria (Australia). Dept. of Chemical Engineering

2004-07-01

180

Small?scale distribution of fish in offshore windfarms  

DEFF Research Database (Denmark)

Knowledge about small?scale distribution of fish around turbines in offshore windfarms (OWF) remains relatively scarce. In the present study we used underwater video camera installations to access abundance of fish at 0, 25, and 50 m around the turbine foundations in Middelgrund and Lillgrund OWFs in Øresund between Denmark and Sweden in the period August–November 2011. Fish fauna in both localities were dominated in terms of numbers by two?spotted gobies (Gobiusculus flavescens). Average number of fish observed per hour was a factor 100 higher at Lillgrund and a factor of 2 higher at Middelgrund at 0 m from the turbine compared to 25 and 50 m away. At Lillgrund sediment was dominated by bare sand while Middelgrund had more heterogeneous sediment types with sand, boulder, pebbles, and dense eelgrass areas. This suggests that OWFs in areas with homogeneous sand sediment have a higher impact on fish fauna compared to OWFs in areas with heterogeneous sediment. Furthermore, the effect of OWFs on fish appears tobe of a much smaller scale than previously thought

Hansen, Kamilla Sande; Stenberg, Claus

2012-01-01

 
 
 
 
181

Small-scale combustion of waste wood from concrete processing  

Energy Technology Data Exchange (ETDEWEB)

Waste wood from concrete processing was tested in a 70 kW wood stove. Normally, this wood has to be landfilled or burned in a waste incineration plant. By means of the experiment, the technical, economic and environmental feasibility of small-scale combustion of the wood was determined. The study leads to the conclusions that combustion of the waste wood from a Dutch concrete processing company in a 1.5 MW wood combustion unit for central heating is technically possible if the installation is equipped with a shredder, a magnetic separator and an automatic ash discharge system. The installation (including shredder, magnetic separator, automatic ash discharge system, multicyclone) is economically for the company. An additional amount of ca. EURO 200.000 can be invested for additional gas cleaning equipment before reaching the economic break-even point. The installation of an electro-filter (ca. EURO 140.000) is recommended, measures to reduce NO{sub x} -emission should be considered. The environmental performance of the process strongly depends on the gas cleaning. If the installation is equipped with a multicyclone, an electrostatic filter and measures to reduce NO{sub x} -emissions, the process can be considered environmentally friendly. Though, dioxin emissions have not sufficiently been taken into consideration. 4 refs.

Dinkelbach, L.; Van der Drift, A. [ECN Biomass, Petten (Netherlands)

2000-06-01

182

Numerical Simulation of a Small-Scale Mild Combustor  

Science.gov (United States)

This work reports numerical simulations of a small-scale cylindrical combustor operating in the mild combustion regime. Preheated air is supplied by a central nozzle, while the fuel (methane) is injected through 16 holes placed equidistantly in a circumference concentric with the air nozzle. The calculations were carried out using the commercial code Ansys-Fluent. Turbulence was modelled using the realizable k-epsilon model. Two different combustion models were employed, namely the eddy dissipation concept and the joint composition pdf transport model. In both cases, a chemical mechanism comprising 13 transported species and 73 chemical reactions was used, as well as a global single-step reaction. A thorough comparison of the predictions obtained using the pdf transport model and the eddy dissipation concept with detailed experimental data is presented. Both models are able to accurately predict the temperature and the O2 and CO2 molar fractions over most of the combustor, but the temperature field is overestimated in the vicinity of the burner. Discrepancies are found in the prediction of the CO molar fraction, particularly when the eddy dissipation concept is used.

Veríssimo, A.; Oliveira, R.; Coelho, P. J.; Costa, M.

2012-11-01

183

Configuration scheme for small scale Multi-FPGA systems  

Directory of Open Access Journals (Sweden)

Full Text Available Multi-FPGA systems have tremendous potential, providing a high-performance computing substrate for many different applications. These systems harness multiple FPGAs, connected in a fixed pattern, to implement complex logic structures.  In order to use such a system effectively, it is a key for constructing a good performance hardware platform. The configuration scheme is an important part in hardware design. This paper aims at small scale Multi-FPGA systems composed of SRAM-based FPGAs developed by Xilinx Corporation,  proposes a novel configuration technique by using Platform Flash PROM XCF32P. Using this scheme, only adopting one XCF32P and one Complex Programmable Logic Device (CPLD) we can configure four FPGAs with monolithic configuration data smaller than 8Mbit. When the number of FPGA is more than four, Design revisioning allows the user to cascade more XCF32P PROMs to realize. Since Xilinx Platform PROM and Xilinx FPGA/CPLD are used to get a single-vender solution, the design for hardware and software is simplified.

Chengchang Zhang; Lisheng Yang; Dangui Yan; Changyong Li

2011-01-01

184

Small scale flow processes in aqueous heterogeneous porous media  

Energy Technology Data Exchange (ETDEWEB)

Small scale flow processes in aqueous heterogeneous porous systems have been studied experimentally via novel nonintrusive fluorescence imaging techniques. The techniques involve 3D visualization and quantification of flow fields within a refractive index-matched transparent porous column. The refractive index-matching yields a transparent porous medium, free from any scattering and refraction at the solid-liquid interfaces, as a result allowing direct optical probing at any point within the porous system. By illuminating the porous regions within the column with a planar sheet of laser beam, flow processes through the porous medium can be observed microscopically, and qualitative and quantitative in-pore transport information can be obtained at a good resolution and a good accuracy. A CCD camera is used to record the fluorescent images at every vertical plane location while sweeping back and forth across the column. These digitized flow images are then analyzed and accumulated over a 3D volume within the column. Series of flow experiments in aqueous, refractive index-matched, porous systems packed with natural mineral particles have been performed successfully in these laboratories.

Rashidi, M.; Dickenson, E. [Lawrence Livermore National Lab., CA (United States). Environmental Programs Directorate

1996-04-01

185

Numerical Simulation of a Small-Scale Mild Combustor  

International Nuclear Information System (INIS)

[en] This work reports numerical simulations of a small-scale cylindrical combustor operating in the mild combustion regime. Preheated air is supplied by a central nozzle, while the fuel (methane) is injected through 16 holes placed equidistantly in a circumference concentric with the air nozzle. The calculations were carried out using the commercial code Ansys-Fluent. Turbulence was modelled using the realizable k-? model. Two different combustion models were employed, namely the eddy dissipation concept and the joint composition pdf transport model. In both cases, a chemical mechanism comprising 13 transported species and 73 chemical reactions was used, as well as a global single-step reaction. A thorough comparison of the predictions obtained using the pdf transport model and the eddy dissipation concept with detailed experimental data is presented. Both models are able to accurately predict the temperature and the O2 and CO2 molar fractions over most of the combustor, but the temperature field is overestimated in the vicinity of the burner. Discrepancies are found in the prediction of the CO molar fraction, particularly when the eddy dissipation concept is used.

2012-11-26

186

MeV Dark Matter and Small Scale Structure  

Energy Technology Data Exchange (ETDEWEB)

WIMPs with electroweak scale masses (neutralinos, etc.) remain in kinetic equilibrium with other particle species until temperatures approximately in the range of 10 MeV to 1 GeV, leading to the formation of dark matter substructure with masses as small as 10{sup -4} M{sub {circle_dot}} to 10{sup -12} M{sub {circle_dot}}. However, if dark matter consists of particles with MeV scale masses, as motivated by the observation of 511 keV emission from the Galactic Bulge, such particles are naturally expected to remain in kinetic equilibrium with the cosmic neutrino background until considerably later times. This would lead to a strong suppression of small scale structure with masses below about 10{sup 7}M{sub {circle_dot}} to 10{sup 4} M{sub {circle_dot}}. This cutoff scale has important implications for present and future searches for faint Local Group satellite galaxies and for the missing satellites problem.

Hooper, Dan; /Fermilab; Kaplinghat, Manoj; Strigari, Louis E.; /UC, Irvine; Zurek, Kathryn M.; /Wisconsin U., Madison

2007-04-01

187

Small Scale Microwave Bursts in Long-duration Solar Flares  

CERN Multimedia

Solar small scale microwave bursts (SMBs), including microwave dot, spike, and narrow band type III bursts, are characterized with very short timescales, narrow frequency bandwidth, and very high brightness temperatures. Based on observations of the Chinese Solar Broadband Radio Spectrometer at Huairou with superhigh cadence and frequency resolution, this work presents an intensive investigation of SMBs in several flares occurred in active region NOAA 10720 during 2005 Jan 14-21. Especially long-duration flares, SMBs occurred not only in early rising and impulsive phase, but also in the flare decay phase, and even in time of after the flare ending. These SMBs are strong bursts with inferred brightness temperature at least 8.18*10^11 - 1.92*10^13 K, very short lifetime of 5-18 ms, relative frequency bandwidths of 0.7-3.5%, and superhigh frequency drifting rates. Together with their obviously different polarizations from the background emission (the quiet Sun, and the underlying flaring broadband continuum), su...

Tan, Baolin

2013-01-01

188

Impact of small-scale geometric roughness on wetting behavior.  

UK PubMed Central (United Kingdom)

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.

Kumar V; Errington JR

2013-09-01

189

ARCADE small-scale docking mechanism for micro-satellites  

Science.gov (United States)

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.

Boesso, A.; Francesconi, A.

2013-05-01

190

Overview of the Testing of a Small-Scale Proprotor  

UK PubMed Central (United Kingdom)

This paper presents an overview of results from the wind tunnel test of a 1/4-scale V-22 proprotor in theDuits-Nederlandse Windtunnel (DNW) in The Netherlands. The small-scale proprotor was tested on theisolated rotor configuration of the Tilt Rotor Aeroacoustic Model (TRAM). The test was conducted by ajoint team from NASA Ames, NASA Langley, U.S. Army Aeroflightdynamics Directorate, and TheBoeing Company. The objective of the test was to acquire a benchmark database for validatingaeroacoustic analyses. Representative examples of airloads, acoustics, structural loads, and performancedata are provided and discussed.NomenclatureC P Rotor power coefficientC T Rotor thrust coefficientFM Rotor hover figure of meritM tip Rotor tip Mach numberPresented at the American Helicopter Society55th Annual Forum, Montreal, Canada, May 2527,1999. Copyright 1999 by the AmericanHelicopter Society, Inc. All rights reserved.R Rotor radiusx/R non-dimensional tunnel longitudinalcoordinate, origin at hub, positivedownstreamy/R non-dimensional tunnel lateralcoordinate, origin at hub, positive onrotor advancing sidez/R non-dimensional tunnel verticalcoordinate, origin at hub, positive upV Wind tunnel test section velocitya s Rotor shaft angle, deg, shaft vertical atzero degrees angle, positive aftm Advance ratio, V/WRh Proprotor efficiency, C T m/C Py Rotor azimuth, deg.W Rotor rotational speed, rad/sIntroductionThe successful introduction of civil tiltrotoraircraft is dependent in part on identifying andreducing, or suppressing, the noise generationmechanisms of tiltrotor aircraft proprotors. Toaccomplish these goals, a series of wind tunneltests with a new generation of tiltrotor models isrequired. The purpose of the Tilt RotorAeroacoustic Model (TRAM)...

Gloria K. Yamauchi; Gavin Botha; Seth Dawson

191

Small-scale swirl events in the quiet Sun chromosphere  

Science.gov (United States)

Context: Recent progress in instrumentation enables solar observations with high resolution simultaneously in the spatial, temporal, and spectral domains. Aims: We use such high-resolution observations to study small-scale structures and dynamics in the chromosphere of the quiet Sun. Methods: We analyse time series of spectral scans through the Ca ii 854.2 nm spectral line obtained with the CRISP instrument at the Swedish 1-m Solar Telescope. The targets are quiet Sun regions inside coronal holes close to disc-centre. Results: The line core maps exhibit relatively few fibrils compared to what is normally observed in quiet Sun regions outside coronal holes. The time series show a chaotic and dynamic scene that includes spatially confined “swirl” events. These events feature dark and bright rotating patches, which can consist of arcs, spiral arms, rings or ring fragments. The width of the fragments typically appears to be of the order of only 0.2 arcsec, which is close to the effective spatial resolution. They exhibit Doppler shifts of -2 to -4 km s-1 but sometimes up to -7 km s-1, indicating fast upflows. The diameter of a swirl is usually of the order of 2´´. At the location of these swirls, the line wing and wide-band maps show close groups of photospheric bright points that move with respect to each other. Conclusions: A likely explanation is that the relative motion of the bright points twists the associated magnetic field in the chromosphere above. Plasma or propagating waves may then spiral upwards guided by the magnetic flux structure, thereby producing the observed intensity signature of Doppler-shifted ring fragments. The movie is only available in electronic form at http://www.aanda.org Marie Curie Intra-European Fellow of the European Commission.

Wedemeyer-Böhm, S.; Rouppe van der Voort, L.

2009-11-01

192

Propulsion engineering study for small-scale Mars missions  

Energy Technology Data Exchange (ETDEWEB)

Rocket propulsion options for small-scale Mars missions are presented and compared, particularly for the terminal landing maneuver and for sample return. Mars landing has a low propulsive {Delta}v requirement on a {approximately}1-minute time scale, but at a high acceleration. High thrust/weight liquid rocket technologies, or advanced pulse-capable solids, developed during the past decade for missile defense, are therefore more appropriate for small Mars landers than are conventional space propulsion technologies. The advanced liquid systems are characterize by compact lightweight thrusters having high chamber pressures and short lifetimes. Blowdown or regulated pressure-fed operation can satisfy the Mars landing requirement, but hardware mass can be reduced by using pumps. Aggressive terminal landing propulsion designs can enable post-landing hop maneuvers for some surface mobility. The Mars sample return mission requires a small high performance launcher having either solid motors or miniature pump-fed engines. Terminal propulsion for 100 kg Mars landers is within the realm of flight-proven thruster designs, but custom tankage is desirable. Landers on a 10 kg scale also are feasible, using technology that has been demonstrated but not previously flown in space. The number of sources and the selection of components are extremely limited on this smallest scale, so some customized hardware is required. A key characteristic of kilogram-scale propulsion is that gas jets are much lighter than liquid thrusters for reaction control. The mass and volume of tanks for inert gas can be eliminated by systems which generate gas as needed from a liquid or a solid, but these have virtually no space flight history. Mars return propulsion is a major engineering challenge; earth launch is the only previously-solved propulsion problem requiring similar or greater performance.

Whitehead, J.

1995-09-12

193

THE EXTREME SMALL SCALES: DO SATELLITE GALAXIES TRACE DARK MATTER?  

International Nuclear Information System (INIS)

We investigate the radial distribution of galaxies within their host dark matter halos as measured in the Sloan Digital Sky Survey by modeling their small-scale clustering. Specifically, we model the Jiang et al. measurements of the galaxy two-point correlation function down to very small projected separations (10 h–1 kpc ? r ? 400 h–1 kpc), in a wide range of luminosity threshold samples (absolute r-band magnitudes of –18 up to –23). We use a halo occupation distribution framework with free parameters that specify both the number and spatial distribution of galaxies within their host dark matter halos. We assume one galaxy resides in the halo center and additional galaxies are considered satellites that follow a radial density profile similar to the dark matter Navarro-Frenk-White (NFW) profile, except that the concentration and inner slope are allowed to vary. We find that in low luminosity samples (Mr r 1/10, which is the fraction of satellite galaxies (or mass) that are enclosed within one-tenth of the virial radius of a halo. We find that M1/10 for low-luminosity satellite galaxies agrees with NFW, whereas for luminous galaxies it is 2.5-4 times higher, demonstrating that these galaxies are substantially more centrally concentrated within their dark matter halos than the dark matter itself. Our results therefore suggest that the processes that govern the spatial distribution of galaxies, once they have merged into larger halos, must be luminosity dependent, such that luminous galaxies become poor tracers of the underlying dark matter.

2012-04-10

194

Financing Small Scale Business Enterprises in Nigeria: A Review of the Problems and the Way Forward  

Directory of Open Access Journals (Sweden)

Full Text Available This study reviewed the problems of financing small scale business enterprises in Nigeria and the way forward. It has identified the sources of finance, types of finance available for small business enterprises and problems inhibiting small scale business enterprises in Nigeria in securing funds for their smooth operations. The study concluded that adequate finance is indispensable for the successful operations of small scale business enterprises in Nigeria and recommended among others that government should increase loanable funds granted to small scale businesses, while micro finance banks should also live up to expectation in granting loanable funds to small scale businesses in Nigeria and a host of others for the effective operations of small scale business enterprises.

Oboro, O. G.; Ighoroje, E. J.

2011-01-01

195

?????????????? The Model of Price Adjustment Mechanisms Focus on Small-Scale Agricultural Products  

Directory of Open Access Journals (Sweden)

Full Text Available ???????????????????????????????????????????????????????????????????????????????????????????????????????????????????????In recent years, prices of Chinese small-scale agricultural product market careen a larger fluctuation, which has seriously affected China’s small-scale agricultural products market’s stability. This paper focuses on building a mechanism to indicate the price movements of agricultural products. Especially in the event of ab- normal phenomenon of prices’ shock, using price adjustment mechanism to ensure that the price level of small- scale agricultural products remain relatively stable condition.

??; ???

2011-01-01

196

Experiments for comparison of small scale rainfall simulators  

Science.gov (United States)

Small scale portable rainfall simulators are an essential tool in research of recent process dynamics of soil erosion. Such rainfall simulators differ in design, rainfall intensities, rain spectra etc., impeding comparison of the results. Due to different research questions a standardisation of rainfall simulation is not in sight. Nevertheless, the data become progressively important for soil erosion modelling and therefore the basis for decision-makers in application-oriented erosion protection. The project aims at providing a criteria catalogue for estimation of the different simulators as well as the comparability of the results and a uniform calibration procedure for generated rainfall. Within the project "Comparability of simulation results of different rainfall simulators as input data for soil erosion modelling (Deutsche Forschungsgemeinschaft - DFG, Project No. Ri 835/6-1)" many rainfall simulators used by European research groups were compared. The artificially generated rainfall of the rainfall simulators at the Universities Basel, La Rioja, Malaga, Trier, Tübingen, Valencia, Wageningen, Zaragoza and at different Spanish CSIC-institutes (Almeria, Cordoba, Granada, Murcia, Zaragoza) were measured with the same methods (Laser Precipitation Monitor for drop spectra and rain collectors for spatial distribution). The data are very beneficial for improvements of simulators and comparison of simulators and results. Furthermore, they can be used for comparative studies with natural rainfall spectra. A broad range of rainfall data was measured (e.g. intensity: 30 - 149 mmh-1, Christiansen Coefficient for spatial rainfall distribution 61 - 98 %, mean drop diameter 0.375 - 5.0 mm, mean kinetic energy expenditure 25 - 1322 J m-2 h-1, mean kinetic energy per unit area and unit depth of rainfall 4 - 14 J m-2 mm-1). Similarities among the simulators could be found e.g. concerning drop size distributions (maximum drop numbers are reached within the two smallest drop classes < 1 mm) and low fall velocities of bigger drops due to a general physical restriction. The comparison provides a good data base for improvements and a consistent picture of the parameters of the simulators. To assess the influence of rainfall simulator type and plot dimensions on runoff and erosion, rainfall simulators from Freiberg, Tübingen, Trier, Valencia, Zaragoza, Basel and Wageningen were compared on a prepared bare fallow field during the Rainfall Simulator Workshop in Trier (Germany). The results show a clear and consistent relationship in runoff, erosion and infiltration behaviour of the different used rainfall simulators. With all the devices total soil loss was measurable, but different plot sizes, intensities and kinetic energies of the simulated rainfall caused differences in soil loss and runoff quantities per unit of area. Regarding course characteristics over runs, similarities could be observed especially in runoff behaviour.

Iserloh, T.; Ries, J. B.

2012-04-01

197

Adoption of Improved Agroforestry Technologies among Contact Farmers in Imo State, Nigeria  

Directory of Open Access Journals (Sweden)

Full Text Available The study examined the adoption of improved agroforestry technologies among farmers in Imo State. To achieve the study objectives, structured questionnaire were designed and administered to ninety farmers who were selected using a multistage random sampling technique. Data collected were analysed using descriptive statistics regression analysis and Pearson product moment correlation (PPMC). Findings shows that the farmers were mainly small scale middle aged married men with secondary education and no access to credit. The average house hold size, farming experience and annual income of the farmers were 6 person, 15.5 years and N 148, 255.6 respectively with two contacts with extension agents on monthly basis. The results indicated that the farmers were largely aware of Gnetum Africana and have adopted plantain/banana technology. The mean adoption rate of agroforestry technologies was 33.81%. The main determinants of the adoption were farmers’ age, educational level, farm size, income, access to credit and extension contact as this variables were all significant. Apart from age of the farmers which was negatively related to adoption of agroforestry technologies all other variables mentioned affected the adoption rate of agroforestry technologies positively. Based on the findings, it was strongly recommended that farmers be provided with loans at concessionary interest rates to solve their financial problem of adopting innovations.

Orisakwe Lambert; Agomuo Florence Ozioma

2012-01-01

198

[Farmer's lung antigens in Germany].  

Science.gov (United States)

Recent studies suggest that besides the long-known farmer's lung antigen sources Saccharopolyspora rectivirgula (Micropolyspora faeni), Thermoactinomyces vulgaris, and Aspergillus fumigatus, additionally the mold Absidia (Lichtheimia) corymbifera as well as the bacteria Erwinia herbicola (Pantoea agglomerans) and Streptomyces albus may cause farmer's lung in Germany. In this study the sera of 64 farmers with a suspicion of farmer's lung were examined for the following further antigens: Wallemia sebi, Cladosporium herbarum, Aspergillus versicolor, and Eurotium amstelodami. Our results indicate that these molds are not frequent causes of farmer's lung in Germany. PMID:22477566

Sennekamp, J; Joest, M; Sander, I; Engelhart, S; Raulf-Heimsoth, M

2012-04-04

199

[Farmer's lung antigens in Germany].  

UK PubMed Central (United Kingdom)

Recent studies suggest that besides the long-known farmer's lung antigen sources Saccharopolyspora rectivirgula (Micropolyspora faeni), Thermoactinomyces vulgaris, and Aspergillus fumigatus, additionally the mold Absidia (Lichtheimia) corymbifera as well as the bacteria Erwinia herbicola (Pantoea agglomerans) and Streptomyces albus may cause farmer's lung in Germany. In this study the sera of 64 farmers with a suspicion of farmer's lung were examined for the following further antigens: Wallemia sebi, Cladosporium herbarum, Aspergillus versicolor, and Eurotium amstelodami. Our results indicate that these molds are not frequent causes of farmer's lung in Germany.

Sennekamp J; Joest M; Sander I; Engelhart S; Raulf-Heimsoth M

2012-05-01

200

Growth rate of small-scale dynamo at low magnetic Prandtl numbers  

International Nuclear Information System (INIS)

[en] In this study, we discuss two key issues relating to a small-scale dynamo instability at low magnetic Prandtl numbers and large magnetic Reynolds numbers, namely: (i) the scaling for the growth rate of a small-scale dynamo instability in the vicinity of the dynamo threshold; (ii) the existence of the Golitsyn spectrum of magnetic fluctuations in small-scale dynamos. There are two different asymptotics for the small-scale dynamo's growth rate: in the vicinity of the threshold of the excitation of the small-scale dynamo instability, ??ln(Rm/Rmcr), and when the magnetic Reynolds number is much larger than the threshold of the excitation of the small-scale dynamo instability, ??Rm1/2, where Rmcr is the small-scale dynamo instability threshold in the magnetic Reynolds number Rm. We demonstrate that the existence of the Golitsyn spectrum of magnetic fluctuations requires a finite correlation time of the random velocity field. On the other hand, the influence of the Golitsyn spectrum on the small-scale dynamo instability is minor. This is the reason why it is so difficult to observe this spectrum in direct numerical simulations for the small-scale dynamo with low magnetic Prandtl numbers. (comment)

2012-01-01

 
 
 
 
201

A Discussion on the Crisis Management of Small Scale Thermal Power Plant Basing on Sustainable Development  

Directory of Open Access Journals (Sweden)

Full Text Available The strategy of sustainable development is one of the two important strategies for Chinese economic development. The present small scale thermal power plants cause much pollution, and consume too much energy, so they are being confronted with the crises of existence and management. Accordingly, it is urgent for small scale thermal power plants to carry out study on the crisis management about their own existence and development. Starting with the deficiencies of small scale thermal power plants, this paper found out the reasons for the difficulties in small scale thermal power plant management and put forward corresponding countermeasures.

Shijun Yang; Dongxiao Niu; Yongli Wang

2009-01-01

202

Characterisation of Particle Emissions from Small-Scale Biomass Combustion  

Energy Technology Data Exchange (ETDEWEB)

Several studies have shown that particulate air pollution is associated with increased mortality. Combustion devices like boilers and internal combustion engines are important sources of particles in the ambient air. In Sweden, the combustion of biomass is increasing and may consequently lead to locally increased particle concentrations. Roughly spoken, particles from biomass combustion consist of ash and of particles originating from incomplete combustion. Several studies of emissions of particles from biomass combustion have been performed, but the particle formation mechanisms are not yet fully understood. The purpose of the present work is to characterise particle emissions from small-scale combustion of wood pellets and wood briquettes, and to contribute with more data on the emission behaviour of biomass-burning boilers. Particle emissions from a pellet stove, two pellet burners and two smaller biomass-fired district heating boilers were studied. Transient effects and influence of operating parameters, such as boiler load and excess air, were investigated. The district heating boilers were fired with wood pellets and wood briquettes and were equipped with multi-cyclones for dust removal. The particle emissions from the district heating boilers were measured downstream of the multi-cyclones. The particle emissions from the domestic heating devices were sampled in the chimney. Number concentrations and number size distributions were determined using an ELPI (Electrical Low -Pressure Impactor). In a few cases an ELPI was operated simultaneously with a SMPS (Scanning Mobility Particle Sizer) to analyse number concentrations and size distributions. Mass concentrations were measured by weighing of collected dust on filters according to Swedish standard. Mass size distributions were determined by a DLPI (Dekati Lo Pressure Impactor). In a few cases analysis of particle composition was carried out with focus on inorganic components. EDX (Electron Dispersive ray) analysis identified the main components. A new method to analyse the mass and molar fractions of alkali compounds, based on TOF-SIMS (Time-of-flight Secondary Ion Mass Spectrometry), was developed. CO, CO{sub 2} , O{sub 2} , THC (total hydrocarbons) were recorded in all cases, to give information about the combustion conditions. In most cases the NO x -emission was recorded as well. Mass concentrations of particles varied from 65 mg/m{sup 3} dry flue gas from the pellet stove to 84 mg/m{sup 3} dry flue gas for the district heating boiler fired with pellets, both emissions normalised to 10 % O{sub 2} . Number concentrations (30 nm - 10 {mu}m) were in the range 10{sup 7} - 10{sup 8}/cm{sup -}3 . The particle emissions were dominated by submicron particles (particle diameter < 1 {mu}m), both from number and mass perspective. The EDX analysis showed that the main inorganic components of the sub-micron particles were potassium, sulphur, chlorine and oxygen. Smaller amounts of sodium, magnesium and zinc were also found. Potassium sulphate was the most common compound and the second most common was potassium chloride.

Johansson, Linda S.

2002-07-01

203

Efficiency of resource use in small-scale white shrimp (Penaeus vannamei) production in Lamongan Regency, East Java Province, Indonesia Wydajno?? wykorzystania zasobów w produkcji bia?ej krewetki (Penaeus vannamei) na ma?? skal? w regencji Lamongan, prowincji Wschodnia Jawa w Indonezji  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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. T...

Riski A. Lestariadi; Sutonya Thongrak; Ratya Anindita

204

Macroscopic High-Temperature Structural Analysis Model for a Small-Scale PCHE Prototype (I)  

Energy Technology Data Exchange (ETDEWEB)

The IHX (intermediate heat exchanger) is a key component of nuclear hydrogen systems for the production of massive amounts hydrogen. The IHX transfers the 950 .deg. C heat generated by the VHTR (very high temperature reactor) to a hydrogen production plant. The Korea Atomic Energy Research Institute established a small-scale gas loop to test the performance of key VHTR components and manufactured a small-scale PCHE (printed circuit heat exchanger) prototype, which is being considered as a candidate for the IHX, for testing in the small-scale gas loop. In this study, as a part of the high-temperature structural integrity evaluation of the small-scale PCHE prototype, we carried out high-temperature structural analysis modeling and macroscopic thermal and structural analysis for the small-scale PCHE prototype under the small-scale gas loop test conditions. This analysis serves as a precedent study to scheduled PCHE 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 and then used to design the medium-scale PCHE prototype.

Song, Kee Nam; Lee, Heong Yeon; Kim, Chan Soo; Hong, Sung Duk [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Park, Hong Yoon [AD Solution, Seoul (Korea, Republic of)

2011-11-15

205

Macroscopic High-Temperature Structural Analysis Model for a Small-Scale PCHE Prototype (I)  

International Nuclear Information System (INIS)

The IHX (intermediate heat exchanger) is a key component of nuclear hydrogen systems for the production of massive amounts hydrogen. The IHX transfers the 950 .deg. C heat generated by the VHTR (very high temperature reactor) to a hydrogen production plant. The Korea Atomic Energy Research Institute established a small-scale gas loop to test the performance of key VHTR components and manufactured a small-scale PCHE (printed circuit heat exchanger) prototype, which is being considered as a candidate for the IHX, for testing in the small-scale gas loop. In this study, as a part of the high-temperature structural integrity evaluation of the small-scale PCHE prototype, we carried out high-temperature structural analysis modeling and macroscopic thermal and structural analysis for the small-scale PCHE prototype under the small-scale gas loop test conditions. This analysis serves as a precedent study to scheduled PCHE 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 and then used to design the medium-scale PCHE prototype

2011-01-01

206

Small-scale hydroelectric power plants pre-designing; Pre-dimensionamento de pequenas centrais hidreletricas  

Energy Technology Data Exchange (ETDEWEB)

This work proposes a new methodology to the small-scale hydroelectric power plants pre-designing. Some costs equations of several structures and equipment of such power plants are presented. The work also aims to contribute significantly to the small-scale hydroelectric power plants studies and development considering Brazilian`s reality 3 refs. 6 figs. 7 tabs.

Martinez, Carlos Barreira; Santos, Afonso Henriques Moreira [Escola Federal de Engenharia de Itajuba, MG (Brazil); Bajay, Sergio Valdir [Campinas Univ., SP (Brazil)

1989-12-31

207

Explanation of small scale irregularities of F-region by ion-ion hybrid drift wave  

Energy Technology Data Exchange (ETDEWEB)

The observed small-scale irregularities in the equatorial F-region are explained in terms of ion-ion hybrid drift instability. It is shown that the complete range of observed small-scale irregularities, i.e., 3m, 1m, 36cm, and 11cm falls within the range of the wavelength of this instability.

Bose, M.; Satya, Y.S.

1994-01-01

208

Establishment of native tropical timber trees in monoculture and mixed-species plantations: Small-scale effects on tree performance and insect herbivory  

UK PubMed Central (United Kingdom)

Plantations of native timber species established on former pasture are a potential strategy to reduce the logging pressure on remnant natural forests in the tropics. Such plantations may help to mitigate or reverse the negative impacts of land degradation, and they may contribute to the long-term livelihood of livestock farmers. Planting native trees is, however, perceived as a risky activity due to limited knowledge of their performance and due to marked losses of newly established seedlings attributed to insect pests. Our study focuses on the small-scale effects of environmental heterogeneity, tree diversity and insecticide treatment on the performance of three native Central American timber species two years after establishment, and on damage inflicted by insect herbivores. Growth, survival and herbivore leaf damage were quantified for Anacardium excelsum (Anacardiaceae), Cedrela odorata (Meliaceae) and Tabebuia rosea (Bignoniaceae) planted in an experiment in Panama as (1) monocultures, (2) mixed stands, and (3) mixed stands protected by insecticides. Our study revealed that small-scale effects can have a substantial impact on the success of timber trees planted on former pasture. Growth performance and survival of the three species was strongly affected by small-scale environmental heterogeneity, which was expressed as significant differences in growth and survival among different plantation plots at the same study site. Establishment of trees in mixed stands did not have significant effects on tree survival and growth compared to pure stands, although it reduced herbivore pressure in one of the studied tree species. All tree species grew best and suffered lowest leaf damage when protected by insecticides, indicating a general influence of insect herbivory on growth of newly established trees. In contrast to growth performance, survival was not significantly affected by different management practices or herbivory. The large variability among plots in tree survival and growth, and also in the effects of management practices such as planting design and insecticide treatment, emphasizes the importance of small-scale environmental heterogeneity on tree survival and growth.

Plath Mirco; Mody Karsten; Potvin Catherine; Dorn Silvia

2011-02-01

209

Growth rate of small-scale dynamo at low magnetic Prandtl numbers  

CERN Multimedia

In this study we discuss two key issues related to a small-scale dynamo instability at low magnetic Prandtl numbers and large magnetic Reynolds numbers, namely: (i) the validity of the scaling, $\\lambda \\propto Rm^{1/2}$, for the growth rate of small-scale dynamo instability in the vicinity of the threshold; (ii) the existence of the Golitsyn spectrum of magnetic fluctuations in small-scale dynamos. Our analysis shows that there are two different asymptotics for the small-scale dynamo growth rate: in the vicinity of the threshold of the excitation of the small-scale dynamo instability, $\\lambda \\propto \\ln(Rm / Rm^{cr})$, and when the magnetic Reynolds number is much larger than the threshold of the excitation of the small-scale dynamo instability, $\\lambda \\propto Rm^{1/2}$, where $Rm^{cr}$ is the small-scale dynamo instability threshold in the magnetic Reynolds number. We also demonstrated that the existence of the Golitsyn spectrum of magnetic fluctuations requires a finite correlation time of the random v...

Kleeorin, N

2011-01-01

210

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

Energy Technology Data Exchange (ETDEWEB)

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

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

2012-02-15

211

Estimating Growth in Investment of Micro and Small Scale Enterprises in Nigeria  

Directory of Open Access Journals (Sweden)

Full Text Available This study analyzed the growth in investment of Micro and Small Scale Enterprises Intermediated by the informal credit market in Nigeria. Primary data for this study were collected from 10 (ten) Local Government Areas of Oyo State, Nigeria using a multi-stage sampling technique. The result indicates that size of lending, experience in lending business have positive and significant impact on growth in investment of micro and small scale enterprises. Policy aimed at making fund increasingly available to small scale enterprises is recommend to boost growth in small and micro enterprises.

Ojenike; Joseph Olusola; Olowoniyi; Adeyemi Olusola

2013-01-01

212

On the Existence of a Critical Magnetic Prandtl Number for Small-Scale Dynamo  

CERN Document Server

We report a series of simulations of homogeneous, isotropic, forced, incompressible MHD turbulence that show that nonhelical small-scale dynamo is shut down at magnetic Prandtl numbers $\\Pr$ below a certain critical value. The effect occurs at magnetic Reynolds numbers for which dynamo exists at larger $\\Pr$. We conclude that the small-scale dynamo is sustainable only if magnetic fluctuations can exist at scales smaller than the scale of the turbulence, i.e., that all small-scale dynamos are, effectively, large-$\\Pr$ ones. Our results are relevant to solar, geo-, and laboratory dynamos.

Schekochihin, A A; Maron, J L; McWilliams, J C

2004-01-01

213

Leptospirosis in trout farmers.  

UK PubMed Central (United Kingdom)

A worker on a trout farm died from serologically confirmed leptospirosis. Four other workers at the trout farm had recently had an influenza-like illness; one had had jaundice. The man with jaundice had high leptospiral antibody titres, and two others had titres of 1/30. The remaining serum sample was negative. Family members and neighbours not associated with the farm had no detectable leptospiral antibodies. There was evidence of rat infestation around the ponds and in a shed used for storing trout food. Pond water or trout food contaminated with rat urine is believed to have been responsible for the outbreak. Another case occurred in a fish farmer elsewhere and it is thought he was infected through wading in rat polluted water with defective rubber boots. A survey to determine the incidence of leptospirosis in fish farm workers is under way.

Robertson MH; Clarke IR; Coghlan JD; Gill ON

1981-09-01

214

Small-scale hydroelectric power in the Pacific Northwest: new impetus for an old energy source  

Energy Technology Data Exchange (ETDEWEB)

Energy supply is one of the most important issues facing Northwestern legislators today. To meet the challenge, state legislatures must address the development of alternative energy sources. The Small-Scale Hydroelectric Power Policy Project of the National Conference of State Legislators (NCSL) was designed to assist state legislators in looking at the benefits of one alternative, small-scale hydro. Because of the need for state legislative support in the development of small-scale hydroelectric, NCSL, as part of its contract with the Department of Energy, conducted the following conference on small-scale hydro in the Pacific Northwest. The conference was designed to identify state obstacles to development and to explore options for change available to policymakers. A summary of the conference proceedings is presented.

1980-07-01

215

Growth and Efficiency of Small Scale Industry and its Impact on Economic Development of Sindh  

Directory of Open Access Journals (Sweden)

Full Text Available The purpose of this study is to analyze the growth, efficiency, causes of sickness of small scale industry, emergence of entrepreneur and competencies of entrepreneurs at Larkana estate area of Sindh Province. The study examines the educational background of the entrepreneurs of small scale industry who are the helm of affairs and its impact on the growth of sales of the every year. Strong evidence emerges that owners of small industrial units are family concern and having a low educational background, lack of managerial knowledge and conservation-oriented attitude results in under utilization of capacity and low growth of units established every year. This research paper provides a survey of the theoretical and empirical literature relating to promote the small scale industry in the Larkana region. This study indicates effective policy measures to promote the small scale industry particularly in Larkana region and generally in Pakistan.

Mumtaz Ali Junejo; Dr. Muhammad Nawaz Chand

2008-01-01

216

Small Scale Purification of Human Pituitary Lutropin (hLH) for Use in Radioligand Assays.  

Science.gov (United States)

Human lutropin (hLH) is a relatively unstable protein, which even in lyophilised form tends to dissociate into subunits during long storage periods. Considering the limited disposibilty of human pituitaries, a small-scale extraction method is proposed for...

I. Schwarz L. Morgante P. Bartolini

1988-01-01

217

Performance of small-scale photovoltaic systems and their potential for rural electrification in Ethiopia  

Energy Technology Data Exchange (ETDEWEB)

The performance of small-scale stand-alone photovoltaic systems is tested under the climatic conditions of Addis Ababa, Ethiopia. With climatic data obtained at a station in the Rift Valley, the photovoltaic systems performance is estimated for those climatic conditions. The economics of small-scale stand-alone photovoltaic system applications under Ethiopian conditions are analysed. The potential of photovoltaics for the rural electrification of Ethiopia is discussed. (Author)

Stutenbaeumer, Ulrich; Negash, Tesfaye; Abdi, Amensisa [Addis Ababa Univ., Dept. of Physics, Addis Ababa (Ethiopia)

1999-09-01

218

Farmer’s union and the economic sustainability of cocoa farmers in Cameroon  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This research on the activities and rule of cocoa farmers unions and organizations in Cameroon and the impact on cocoa farming, I will be looking at cocoa farmers unions in Cameroon and what they do to improve on the quality of cocoa farming while looking at how they have helped to make cocoa farmi...

Ambrose Kwankam, Njila

219

The value of guanxi for small vegetable farmers in China.  

UK PubMed Central (United Kingdom)

Purpose -- Following a guanxi value -- buyer-seller relationship quality -- marketing behaviour scheme, this paper aims to explore how traditional guanxi supports small vegetable farmers in modern markets in China. Design/methodology/approach -- Fieldwork was performed in Jiangsu Province, PR China. A stratified random sample of 167 vegetable farmers provided data for empirical testing with partial least squares analysis. Findings -- The findings suggested that the value of guanxi networks is an antecedent to buyer-seller relationship quality and marketing behaviour in China. Guanxi networks improve the quality of buyer-seller relationships in terms of interpersonal trust and satisfaction. Buyer-seller relationships influence smallholders' transaction relationships, their participation in modern markets and choice for formal contracts. Guanxi networks not only support Chinese small-scale vegetable farmers to get access to modern high-value markets (e.g. supermarkets and international markets), but also encourage informal transactions in the vegetable business. Practical implications -- Guanxi networks play a critical role in the modern marketing environment in China. Marketing strategies based on personal relationships should be further enhanced in order to increase participation of smallholders in modern markets. Originality/value -- Quantitative evaluation of the effects of the Chinese cultural embedded concept of guanxi in the Chinese agrifood sector fills in an important research gap.

Lu Hualiang; Trienekens JacquesH; Omta SWF; Feng Shuyi

2008-01-01

220

Health and Safety Management for Small-scale Methane Fermentation Facilities  

Science.gov (United States)

In this study, we considered health and safety management for small-scale methane fermentation facilities that treat 2-5 ton of biomass daily based on several years operation experience with an approximate capacity of 5 t·d-1. We also took account of existing knowledge, related laws and regulations. There are no qualifications or licenses required for management and operation of small-scale methane fermentation facilities, even though rural sewerage facilities with a relative similar function are required to obtain a legitimate license. Therefore, there are wide variations in health and safety consciousness of the operators of small-scale methane fermentation facilities. The industrial safety and health laws are not applied to the operation of small-scale methane fermentation facilities. However, in order to safely operate a small-scale methane fermentation facility, the occupational safety and health management system that the law recommends should be applied. The aims of this paper are to clarify the risk factors in small-scale methane fermentation facilities and encourage planning, design and operation of facilities based on health and safety management.

Yamaoka, Masaru; Yuyama, Yoshito; Nakamura, Masato; Oritate, Fumiko

 
 
 
 
221

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

Energy Technology Data Exchange (ETDEWEB)

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.

Song, Kee Nam; Lee, Heong Yeon; Hong, Sung Deok [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Park, Hong Yoon [AD Solution, Seoul (Korea, Republic of)

2011-09-15

222

Handling uncertainty : policy and organizational practices in Tanzania's small-scale gold mining sector  

DEFF Research Database (Denmark)

Small-scale mining supports the livelihoods of several hundred thousand rural households in Africa. Nonetheless, the understanding of the organizational dynamics of small-scale miners' activities is modest. The paper outlines the small-scale mining codes in Tanzania and contrasts them to prevalent organizational practices in two Tanzanian small-scale mining settlements. It is argued that there is a need to adjust the regulatory mechanisms to well-consolidated practices: If basic practices differ substantially from official prescriptions of the mining codes over an extended period of time, certain elements of the regulatory framework need reconsideration. The paper examines three pertinent operational components that vary in form and managing practices between the two study sites: dealing with licence acquisition, accessing working capital, and sharing output. These components are considered vital for the proper manoeuvring of local small-scale mining operators and the reasons for the variations are essential to understand for policymakers and development practitioners. By incorporating prevalent practices and context-dependent variations in some of the crucial organizational components, it is possible to design a robust and resilient regulatory framework for small-scale mining. A number of policy adjustments are consequently proposed.

JØnsson, Jesper Bosse; Fold, Niels

2009-01-01

223

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

International Nuclear Information System (INIS)

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

2011-01-01

224

Mortality in the California Farmer Health Study cohort.  

UK PubMed Central (United Kingdom)

Western agriculture, in comparison with Midwestern and Eastern, is more diverse, with a drier climate, mild winters, and different exposures. This randomly selected cohort of 1947 Californian farmers confirmed the usual finding: a lower mortality rate than general population (by 50%). A low smoking prevalence and healthy worker effect are likely contributors. Although farmers were more likely to die from injuries and skin cancer, death was less likely from Alzheimer's and cerebrovascular diseases. Within the cohort, disability and persistent wheeze were associated with increased mortality. The 200 deaths were insufficient to determine the significance of rare diseases.

Armitage TL; Mitchell D; Schenker M

2012-01-01

225

Perspectives on small--scale spatial structure of plant species in plant communities  

UK PubMed Central (United Kingdom)

Small-scale spatial structure of plant species is important in plant e cology as it affects the dynamics of plant populations, communities and ecosyste m processes. Plants interact primarily with their immediate neighbors, and the v iew of the community as seen by an individual plant can be quite different from processes averaged over large spatial scales. Many processes influence the forma tion and dynamics of small-scale spatial structures of plant species, and local spatial structure in turn has an effect on the vital processes of plant growth, birth and death. This paper summarizes developments in this area of research bas ed on the extensive literature on small-scale spatial structure of plant species to help direct further research efforts. Firstly, this paper introduces six fac tors that lead to the formation of small-scale spatial structure of plant specie s, including (1) habitat spatial heterogeneity, (2) dispersal of propagules, (3) in teractions between plants, (4) effects of the biological environment (animals and microbes), (5) effects of exoteric disturbances, and (6) the integrated effects o f many factors. The significance and effects of small-scale spatial structure on studies of biological diversity, plant population genetics and restoration ecol ogy are then examined. Finally, several questions were raised and a list of sugg ested areas of future research on this topic were presented that included: (1) In f ormation on small-scale spatial structure should be integrated into vegetation dynamics at large scales; (2) Either biologically or ecologically, the research ab out small-scale spatial structure of vegetation should focus on plants, make cer tain the adequate scale and adopt correct spatial statistical methods; (3) The pr actical implications of small-scale spatial structure for degraded ecosystems sh ould be highly taken into account; (4) Integration of whole community characteris tics should begin with local patterns on small scales; and (5) Small-scale spatia l structure should be combined with traditional mean-field theory in order to de eply explore plant community dynamics.

Liu Zhenguo; Li Zhenqing

2005-01-01

226

An analysis of the Peruvian jungle cocoa farmers: Acopagro cooperative vs. Intermediaries- A case of study  

Directory of Open Access Journals (Sweden)

Full Text Available In the Peruvian jungle, there are two main cocoa marketing channels: the intermediaries and the cooperative. TheAcopagro Cooperative, a Peruvian organization, for example, has contributed to the shift from illegal crops likecoca to an alternative crop like cocoa which gives small scale farmers a sustainable welfare. A survey of 243farmers in Juanjui, San Martin-which is the main cocoa production area in Peru-was carried out betweenDecember 2009-January 2010. This study analyzes Peruvian cocoa farmers’ socio-economic characteristics asthese attributes affect their decision-making process in the cocoa commercialization for their self-improvementand evaluates if the farmers’ participation in Acopagro or not influences the increment of the cocoa production.Policy makers and farmers’ organizations should consider these results in order to contribute to improve thecompetitiveness of the farmers’ marketing channels not only towards the development of these organizations’but also to that of their communities as a whole.

A. Higuchi; M. Moritaka; S. Fukuda

2010-01-01

227

Farmer Suicide and Community Policing  

Directory of Open Access Journals (Sweden)

Full Text Available Agriculture has always been celebrated as the primary and predominant sector in the Indian economy. True to this, close to 70 percent of the people still depend on agriculture and allied activities for their livelihood. The major portion of Indian farming is dependent on natural rain fall. The rainfall in India is unpredictable. Failure of rains results failure of crops, as a result the farming community falls in the debt trap and the farmers who fail to overcome these problems may take an extreme step of ending their life. In the present paper an effort is made to discuss the role of community police in the prevention of suicides among farmers. In the community policing there is involvement of citizens in crime prevention process. Various suggestions like educating the farmers on the values of life, about the facilities available to them, designing a model program for prevention of farmer's suicides etc have been discussed in the present paper.

Purnanand. N. Sangalad

2012-01-01

228

Small-scale production of fuel chips - Harvesting methods, power requirement and working environment. Smaaskalig produktion av braensleflisdrivningsmetoder, effektbehov och arbetsmiljoe  

Energy Technology Data Exchange (ETDEWEB)

Fuel chips can be produced with large-scale or small-scale methods. Small-scale methods are primarily meant for producing chips for heating the houses of the farmer or forest owner. The equipment used are small chippers which are fed manually and have a farm tractor as power source. This paper summarizes three studies with the objective to describe some small-scale chipping methods regarding productivity, power requirement and work environment. Conventional time studies were carried out as well as more controlled experiments. The productivity was about 2 m{sup 3}l (loose cubic metre) chips per effective work hour. There is a strong relationship between productivity and tree diameter (DBH) for wood taken from precommercial thinnings and from stands of harwood thickets. In thinnings, the highest productivity was achieved in an integrated harvest of wood fuels and industrial wood, according to the so called tree-method. The studies indicated a relationship between the power requirement and the diameter of the tree. To handle a maximum wood diameter of 20 cm a power of 60-70 kW is required, while a log of half the diameter (10 cm) only required about 20 kW. Other factors that were found to be important for the power requirement were the moisture content of the wood, the air temperature at the time of chipping (if below freezing) and the rotating speed of the chipper. Furthermore, the studies show that working with a chipper is a pronounced labour of arms, and that the oxygen consuption - litre O{sub 2}/tonne chips - decreases with higher piece-weight. It also shows that the work load was lower when some sort of hand tools (hooks or tongs) were used when handling heavy loads or if piles were low. Accident risks and noise levels have also been studied. (au).

Liss, J.E. (Swedish Univ. of Agricultural Sciences, Garpenberg (SE). Dept. of Operational Efficiency)

1990-05-01

229

THE PERFORMANCE OF SMALL SCALE INDUSTRIES: A CASE STUDY OF OSMANABAD DISTRICT  

Directory of Open Access Journals (Sweden)

Full Text Available Small Scale Industry is one of the major components of our economic development which provides more employment opportunities particularly to the rural people, export potentials and acts as ancillary units for the large scale industry. Small Scale Industry is the blood stream of the Indian economy. They feed the large industries and they cannot survive without small units, which are the major source of innovation in Indian Industry. But these units are facing certain problems such as finance, marketing, non-availability of raw material, low productivity etc. In this study we have analyzed the growth and trend in production, working capital and employment in small scale industries during the year 1998-99 to 2007-08. Thus this paper highlighted the performance of the Small Scale Industries in the Osmanabad district. It is concluded that the performance of the Small Scale Industries in the Osmanabad district is a good. If they got the effective services and facilities from the Government and Institutions, they can perform very well in future. They may increase in production, employment and income.

AJIT ASHTE; ASWALE S. N.

2013-01-01

230

GENDER DIFFERENTIALS IN FACTORS AFFECTING PERFORMANCE OF SMALL-SCALE ENTERPRISES IN LAGOS STATE – NIGERIA  

Directory of Open Access Journals (Sweden)

Full Text Available There is a lack of empirical data segregation on factors affecting gender as the variable of interest. However, previous research had indicated several factors that affect business performances among small-scale enterprise owners. Using feminist theory and a descriptive survey research design, data were collected from fifty (50) small-scale enterprise owners that were purposively chosen across the study area. The findings show that the factors that were significant for female were significantly different from male. For female small scale enterprise owners, marital status (64%) Age of Children (68%), Role Model/ advisors (58%) were significant factors that affect their business performance. For male small-scale enterprise owners, Friends (70%), a lack of Government support (80%), inability to display innovativeness (78%) and Risk-Taking (84%) were significant for male. Lack of availability of capital and finances were significant for the two. Other factors that affect performance include friends, inadequate training and business location. Adequate knowledge of factors that affect gender enterprise performance will go a long way in alleviating these problems. Small-scale enterprises should be supported for poverty alleviation, especially among women and for the nation’s economic development

Yusuff Olabisi Sherifat

2013-01-01

231

European small scale wood harvesting technology will be mapped out; Puunkorjuun eurooppalaista pienteknologiaa kartoitetaan  

Energy Technology Data Exchange (ETDEWEB)

At the beginning of this year the Forestry Department at the TTS-Institute started an EU-project, in which the state and development needs of small-scale wood harvesting technology will be mapped out in 13 different European countries. The research subject will be observed using the technology and the rural development point of view. The first one promotes the technology transfer by increasing the information about small-scale wood harvesting technology. Developing specialization, cooperation and entrepreneurship of forest owners in rural areas will carry out the second one. TTS-Institute acts as coordinator in the project, which lasts for 2,5 years. Readiness for this task comes from the TTS-Institute's specialisation in research and development activities around small-scale technology forest work. (orig.)

Lahdensaari, L. [Work Efficiency Inst., Helsinki (Finland)

2000-07-01

232

We must emphasize solving the problem of environmental pollution caused by small-scale industry. [China  

Energy Technology Data Exchange (ETDEWEB)

This article proposes that solving the problem of environmental pollution caused by small-scale industry managed by counties, communes and brigades and protecting the agricultural environment are new issues that must be emphasized during China's socioeconomic development. China has more than 1.4 million commune and brigade enterprises, which employ over 30 million people. Disadvantages of the small-scale enterprises include irrational distribution, poor technical equipment, bad management, and the lack of antipollution devices. It is suggested that the construction of factories must not be permitted upwind from cities and towns, in dense residential districts or water protection areas, or near scenic tourist spots, sanitariums, natural preserves, famous relics or hot springs. The development of small-scale industry should be integrated with the growth of cities, towns and villages through unified planning and rational distribution.

Zhang Guoguang

1983-08-25

233

Small-scale field-aligned currents observed by the AKEBONO (EXOS-D) satellite  

Energy Technology Data Exchange (ETDEWEB)

The EXOS-D fluxgate magnetometer data obtained at 3,000-10,000 km altitude have shown that small-scale field-aligned currents always exist in large-scale region 1, region 2, cusp and polar cap current systems. Assuming that these small-scale field-aligned currents have current sheet structure, the width of current sheet is estimated to be 5-20 km at ionospheric altitude. By comparing the magnetometer data with charged particle and high frequency plasma wave data simultaneously obtained from EXOS-D, it is found that small-scale currents have one-to-one correspondence with localized electron precipitation events characterized by flux enhancement over a wide energy range from 10 eV to several keV and broadband electrostatic bursts occasionally extending above local plasma frequencies or electron cyclotron frequencies.

Fukunishi, H.; Oya, H. (Tohoku Univ. (Japan)); Kokubun, S. (Univ. of Tokyo (Japan)); Tohyama, F. (Tokai Univ. (Japan)); Mukai, T.; Fujii, R.

1991-02-01

234

Responding to the challenge of artisanal and small-scale mining. How can knowledge networks help?  

Energy Technology Data Exchange (ETDEWEB)

This paper reviews what is known about the problems and structural challenges facing the 20-30 million artisanal and small-scale miners and their communities worldwide. Better understanding of these structural challenges is needed to improve policies and policy implementation to further sustainable development opportunities for the sector. The paper explores the current gaps in knowledge to achieve policy change from researchers, practitioners and artisanal and small-scale miners themselves. It explores how a 'knowledge intermediary', which acts to link knowledge with policy, could address these gaps and includes case studies of IIED’s work on knowledge networks and programmes. The paper concludes by proposing a way forward for designing a knowledge programme to meet the particular needs of the artisanal and small-scale mining (ASM) sector, and by inviting ASM sector stakeholders to share their views on the options outlined.

Buxton, Abbi

2013-02-15

235

Small Scale Effect on Thermal Vibration of Single-Walled Carbon Nanotubes with Nonlocal Boundary Condition  

Directory of Open Access Journals (Sweden)

Full Text Available In this study, a single beam model has been developed to analyze the thermal vibration of Single-Walled Carbon Nanotubes (SWCNT). The nonlocal elasticity takes into account the effect of small size into the formulation and the boundary condition. With exact solution of the dynamic governing equations, the thermal-vibrational characteristics of a cantilever SWCNT are obtained. Influence of nonlocal small scale effects, temperature change and vibration modes of the CNT on the frequency are investigated. The present study shows that the additional boundary conditions from small scale do not change natural frequencies at different temperature change. Thus for simplicity, one can apply the local boundary condition to replace the small scale boundary condition.

Li Ming; Zheng Huiming

2013-01-01

236

Proceedings of a workshop on agroforestry tree seeds for farmers  

DEFF Research Database (Denmark)

Forest & Landscape Denmark, ICRAF and National Tree Seed Centres in three African countries implement an innovative twinning project. The project seeks to identify the major constraints and opportunities for improving seed/seedling production and distribution to small-scale tree-planting farmers in Sub-Saharan Africa. The project analyses existing production and distribution systems in three countries (Malawi, Uganda and Burkina Faso) and will test innovations on seed systems in pilot projects. A situation analysis of the Malawi tree seed sub sector carried out by this project has been prepared. This report presents the findings from the workshop. It provides information on workshop presentations and discussions as well as findings by working groups.

LillesØ, Jens-Peter Barnekow

2007-01-01

237

Collective backscattering of gyrotron radiation by small-scale plasma density fluctuations in large helical device.  

Science.gov (United States)

A version of the collective backscattering diagnostic using gyrotron radiation for small-scale turbulence is described. The diagnostic is used to measure small-scale (k(s) approximately 34 cm(-1)) plasma density fluctuations in large helical device experiments on the electron cyclotron heating of plasma with the use of 200 kW 82.7 GHz heating gyrotron. A good signal to noise ratio during plasma production phase was obtained, while contamination of stray light increased during plasma build-up phase. The effect of the stray radiation was investigated. The available quasioptical system of the heating system was utilized for this purpose. PMID:19044538

Kharchev, Nikolay; Tanaka, Kenji; Kubo, Shin; Igami, Hiroe; Batanov, German; Petrov, Alexandr; Sarksyan, Karen; Skvortsova, Nina; Azuma, Yoshifumi; Tsuji-Iio, Shunji

2008-10-01

238

Collective backscattering of gyrotron radiation by small-scale plasma density fluctuations in large helical device.  

UK PubMed Central (United Kingdom)

A version of the collective backscattering diagnostic using gyrotron radiation for small-scale turbulence is described. The diagnostic is used to measure small-scale (k(s) approximately 34 cm(-1)) plasma density fluctuations in large helical device experiments on the electron cyclotron heating of plasma with the use of 200 kW 82.7 GHz heating gyrotron. A good signal to noise ratio during plasma production phase was obtained, while contamination of stray light increased during plasma build-up phase. The effect of the stray radiation was investigated. The available quasioptical system of the heating system was utilized for this purpose.

Kharchev N; Tanaka K; Kubo S; Igami H; Batanov G; Petrov A; Sarksyan K; Skvortsova N; Azuma Y; Tsuji-Iio S

2008-10-01

239

The life-cycle of drift-wave turbulence driven by small scale instability  

CERN Document Server

We demonstrate theoretically and numerically the zonal-flow/drift-wave feedback mechanism for the LH transition in an idealised model of plasma turbulence driven by a small scale instability. Zonal flows are generated by a secondary modulational instability of the modes which are directly driven by the primary instability. The zonal flows then suppress the small scales thereby arresting the energy injection into the system, which can be described using nonlocal wave turbulence theory. Finally, the arrest of the energy input results in saturation of the zonal flows at a level which can be estimated from the theory and the system reaches stationarity without damping of the large scales.

Connaughton, Colm; Quinn, Brenda

2010-01-01

240

Investigations on the nutrient and antinutrient content of typical plants used as fish feed in small scale aquaculture in the mountainous regions of Northern Vietnam  

UK PubMed Central (United Kingdom)

The aquaculture system of the Black Thai farmers in the upland of Northern Vietnam mostly depends on green leaves which they use as major feed input to the ponds. A study was conducted to assess the quality of two groups of plant residues used as fish feed (principally for grass carp) in Northern Vietnam. The first group was constituted of residues commonly fed to fish, such as cassava (Manihot esculenta), banana (Musa nana), and bamboo (Bambusa vulgaris) leaves, and the second group included residues occasionally fed to fish by farmers, such as barnyard grass (Echinochloa erusgalli), mixed weeds from paddy fields, Elephant grass (Pennisetum purpureum), mulberry (Morus), maize (Zea mays), sweet potato (Ipomoea batatas), peanut (Arachis hypogaea); cassava tubercles and crop residues such as rice bran, cassava peels. In the first group of plant material analysed any possible temporal changes in their nutrient, energy and antinutrient contents during the course of the year were evaluated, whereas in the second group the nutrient, energy and antinutrient content were determined, without any evaluation of their temporal changes. No significant temporal changes were observed in the proximate composition, energy and antinutrient contents of banana leaves during the course of the year. Significant (P<0.05) temporal changes were observed in the proximate composition of cassava and bamboo leaves as well as in the content of some antinutrient of cassava leaves. Results of proximate analysis indicated the high potential of some of these plant materials such as cassava and mulberry leaves as fish feed because of their higher protein and energy content. However, the protein and energy content of these leaves were generally very low when compared to that of the common standard fish feed. Thus, these plant feedstuffs alone may not be sufficient to cover the requirements for rapid growth in cultured grass carp. The data presented here could be used for formulating cost-effective and balanced animal feeds for the use of small-scale farmers in rural areas in Northern Vietnam.

Dongmeza E; Steinbronn S; Francis G; Focken U; Becker K

2009-03-01

 
 
 
 
241

Individual Factors Affecting Farmers’ Motivation to Participate in Date Growers’ Organizations in Khuzestan  

Directory of Open Access Journals (Sweden)

Full Text Available Khuzestan Province has a great share in Iran’s date production in which many rural households are directly dependent to dates production. However, small holding system has led to a lot of challenges faced by small scale farmers whereas much potential of date production and marketing lost every year. Despite of strong felt need to social capital development and government’s recent activities in order to help farmers to organize themselves, there is not so much interest in this connection generally. So, the purpose of this study was to provide a framework for understanding the individual factors affecting farmers’ motivation to participate in date growers’ organizations. The population of the research consisted of 584 members of five present date growers’ organizations. By the use of Cochran Formula, 120 farmers were randomly selected as research sample. Data were gathered trough a researcher-made questionnaire and analyzed by the use of SPSS software. The results of multiple regression analysis indicated that three independent variables namely "degree of formal education", "attendance in extension-education courses" and "years of date growing", predicted 62% of variation of farmers’ total motivation to participate in date growers’ organizations.

E. Alimirzaei; A. Asady

2011-01-01

242

A cross sectional survey of knowledge, attitude and practices related to house flies among dairy farmers in Punjab, Pakistan.  

UK PubMed Central (United Kingdom)

BACKGROUND: House flies are of major public health concerns in areas with poor sanitation and hygienic conditions. Unfortunately, sanitation and hygiene have always been ignored in dairy farms particularly in the developing or low-income countries. Management of these flies mostly depends on the awareness regarding associated hazards and protective measures taken by the people to minimize risks associated with flies. The present study therefore explores the knowledge, attitude and practices taken by dairy farmers in Punjab, Pakistan against house flies. METHODS: The present study was based on a cross sectional self administered survey to a convenience sample of 173 small scale dairy farmers in four localities - Multan, Lahore, Shorkot and Faisalabad - of Pakistan. The relationships between socio-demographics, knowledge and preventive practices were investigated through logistic regression analysis and chi-square test of association. RESULTS: Considerable number of dairy farmers 71/173 (41.04%) had no idea about the problems associated with house flies. Although 77/173 (44.51%) dairy farmers reported house flies as disease transmitters, only 23 (29.87%) farmers were familiar with diseases and 22 (28.57%) had somewhat idea of the mode of disease transmission. We found a positive association between dairy farmer's education level and overall knowledge of house flies in multivariate analysis. Farmer's education level and knowledge of the house flies breeding sites had a positive association with the adoption of house fly prevention practices by the respondents. However, knowledge of the problems associated with house flies and preventive measures had no association with house fly prevention practices. CONCLUSION: The present ethnoentomological survey provides information about knowledge, attitude and practices of dairy farmers related to house flies in Punjab, Pakistan. We conclude that the farmers' education level and knowledge of the breeding sites had a positive association with the adoption of prevention practices against house flies. The study also highlights the need of targeting the lack of knowledge of dairy farmers for the successful management of house flies.

Khan HA; Akram W; Shad SA; Razaq M; Naeem-Ullah U; Zia K

2013-01-01

243

Small-scale topology of solar atmosphere dynamics : II : granulation, K2v grains and waves  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We continue studying the small-scale topology of dynamical phenomena in the quiet-sun internetwork atmosphere throug statistical estimation of the co-location probability of different fine-structure elements and wave modes.In this paper we chart spatial alignments between the granular brig tness st...

Hoekzema, N.M.; Rutten, R.J.

244

Small-scale topology of solar atmosphere dynamics I: wave sources and wave diffraction  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We study the small-scale topology of dynamical phenomena in the quiet-sun internet w ork atmosphere,using short-duration Fourier analysis of high-resolution filtergram sequences to obtain statistical estimates for the co-location probability of different fine-structure elements and wave modes. In th...

Hoekzema, N.M.; Rutten, R.J.; Brandt, P.N.; Shine, R.A.

245

The potential of energy efficiency measures in micro and small scale businesses in Kumasi-Ghana  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In industry, energy efficiency reduces operating cost and emissions to the environment whiles enhancing energy security. In order to ensure the sustainability of micro and small scale businesses in a developing country such as Ghana, measures that can ensure energy efficiency are therefore essential...

Kuranchie, Francis Atta

246

Small-Scale Bullying Prevention Discussion Video for Classrooms: A Preliminary Evaluation  

Science.gov (United States)

Bullying has been shown to be negatively related to both academic performance and attendance among students. The present study examined a small-scale bullying intervention using a video-discussion model. Eighty-one students in grades 4 through 6 completed pre- and posttests examining gains in knowledge of bullying and responses to it. Results…

Migliaccio, Todd; Raskauskas, Juliana

2013-01-01

247

Factors affecting Small-Scale Coffee Production in Githunguri District, Kenya  

Directory of Open Access Journals (Sweden)

Full Text Available This study was carried out to determine the factors affecting small scale coffee production in Kenya. The establishments under study were small-scale coffee farms in Githunguri District.It was to determine whether marketing factors, finances, government policies and physical and human resources affect coffee production in Githunguri District. Primary sources included use of questionnaires, observation and interviews. Secondary sources included desk research, library research on journals, text books and factory publications. The target population was over 700,000 small-scale coffee producers in Kenya out of which the accessible population of 10,000 producers drawn from Githunguri District in Kiambu County was selected which a sample size of 120 respondents was sampled. Stratified sampling technique was employed to compare views among coffee producers from the various coffee societies in the area. Data analysis was both qualitative and quantitative using descriptive statistics. Data presentation was in form of tables to help interpret findings and generate conclusions that aided solutions to identified problems. The research established that marketing factors, finances, government policies and physical and human resources greatly affected coffee production. The study recommended that the government should encourage coffee production by formulating favorable marketing factors and other policies and provide finances to small scale coffee producers. Producers on the other hand should strive to provide conducive working environment to their workers so as to sustain them in their farms. This will help to improve coffee yields and quality.

Margaret Njeri Gathura

2013-01-01

248

Biomimetic Micro Air Vehicle Testing Development and Small Scale Flapping-Wing Analysis.  

Science.gov (United States)

The purpose of this research was to develop testing methods capable of analyzing the performance of a miniature flapping-wing mechanism that can later be adapted for the development a biomimetic flapping-wing micro air vehicle (MAV). Three small scale fla...

C. E. Svanberg

2008-01-01

249

Direct driven axial flux permanent magnet generator for small-scale wind power applications  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Small-scale wind power applications require a cost effective and mechanically simple generator in order to be a reliable energy source. The use of direct driven generators, instead of geared machines, reduces the number of drive components, which offers the opportunity to reduce costs and increases ...

Ferreira, Ângela; Costa, Artur

250

The impact of small-scale turbulence on laminar magnetic reconnection  

International Nuclear Information System (INIS)

Initial states in incompressible two-dimensional magnetohydrodynamics that are known to lead to strong current sheets and (laminar) magnetic reconnection are modified by the addition of small-scale turbulent perturbations of various energies. The evolution of these states is computed with the aim of ascertaining the influence of the turbulence on the underlying laminar solution. Two main questions are addressed here: (1) What effect does small-scale turbulence have on the energy dissipation rate of the underlying solution? (2) What is the threshold turbulent perturbation level above which the original laminar reconnective dynamics is no longer recognizable. The simulations show that while the laminar dynamics persist the dissipation rates are largely unaffected by the turbulence, other than modest increases attributable to the additional small length scales present in the new initial condition. The solutions themselves are also remarkably insensitive to small-scale turbulent perturbations unless the perturbations are large enough to undermine the integrity of the underlying cellular flow pattern. Indeed, even initial states that lead to the evolution of small-scale microscopic sheets can survive the addition of modest turbulence. The role of a large-scale organizing background magnetic field is also addressed.

251

The Effect of Small-Scale Industry on Local Development Case Study: Karak Governorate  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The study aimed at knowing the characteristics of SmallScale Industries SSIs in the governorate of karak and its important role in local development, Analyzing the relationship between the characteristics of SSIs that include the nature of activity, financing and location and the local de...

Salah T. Al-Rawashdeh

252

Musculoskeletal pain in women working in small-scale agriculture in South Africa  

Digital Repository Infrastructure Vision for European Research (DRIVER)

BACKGROUND: Musculoskeletal pain is associated with demographic, occupational and physical factors. METHODS: Our study investigated the prevalence and factors associated with musculoskeletal pain in 911 women working in small-scale agriculture in rural northern KwaZulu-Natal, South Africa in 2006 us...

Naidoo, S.; Kromhout, H.; London, L.; Naidoo, R.N.; Burdorf, A.

253

Small-scale ethanol production from corn: technology, energy efficiency, and economics  

Energy Technology Data Exchange (ETDEWEB)

Several options are compared for small scale ethanol production systems (up to 800,000 1/year) in terms of technology, energy efficiency, and economics. Small scale plants, in general, are also compared with large scale plants. The options discussed for small scale plants are: batch distillation versus continuous feed distillation; packed distillation column versus perforated-plate column; by-product solids separation prior to distillation versus pumping solids into distillation column versus perforated-plate column; by-product solids separation prior to distillation versus pumping solids into distillation column; vacuum distillation versus atmospheric distillation; and direct-fired reboiler and a mash cooking tank versus separate boiler used to generate steam for heating them. These options are compared in the context of three types of systems which have been used or proposed for small scale ethanol production: batch-type reflux distillation system with the same vessel used as cooker, fermenter, and for distillation; continuous-feed, perforated-plate reflux distillation system, without solids separation, using a separate boiler for heat supply for distillation; continuous feed, packed, reflux distillation column, with a direct-fired reboiler and solids separation before distillation. 13 references, 6 figures, 7 tables.

Bengston, H.H.

1983-11-01

254

Small scale ethanol production from corn - technology, energy efficiency and economics  

Energy Technology Data Exchange (ETDEWEB)

This paper compares several options for small scale ethanol production systems (up to 800,000 1/year) in terms of technology, energy efficiency, and economics. Small scale plants in general are also compared with large scale plants. The options discussed for small scale plants are: batch distillation versus continuous feed distillation; packed distillation column versus perforated-plate column; by-product solids separation prior to distillation versus pumping solids into distillation column; vacuum distillation versus atmospheric distillation; and direct-fired reboiler and mash cooking tank versus separate boiler used to generate steam for heating them. These options are compared in the context of three types of systems which have been used or proposed for small scale ethanol production: batch-type reflux distillation system with the same vessel used as cooker, fermenter, and for distillation; continuous-feed, perforated-plate reflux distillation system, without solids separation, using a separate boiler for heat supply for distillation; continuous feed, packed, reflux distillation column, with a direct-fired reboiler and solids separation before distillation.

Bengtson, H.H.

1983-01-01

255

Fostering sustainable small-scale investments: lessons from experience and ideas for intervention and innovation  

International Nuclear Information System (INIS)

This article presents lessons from experience pertinent to implementing small-scale natural resource and related investment projects in developing countries. It outlines ideas for intervention and innovation to foster such investments. Particular emphasis is placed on private-sector participation in these investments. Following a brief presentation of the economic development and other arguments that support intervention and innovation in support of such small-scale natural resource investments, the article discusses many of the lessons learned from experience. These lessons reinforce those touched upon in the investment-specific discussions in the previous articles. The experience and associated lessons that are examined include experiences in both developing and developed countries and encompass nor just lessons from natural resource investments, but also small-scale investments in other sectors. Financing and other innovations which facilitate meeting the challenges are drawn from relevant experience where barriers to investment have been surmounted. Options for programme and project interventions to increase market penetration of small-scale investments and achieve the associated development linkages and synergies are suggested. These suggestions are aimed especially at governments and bilateral and multilateral development finance and development assistance entities. It is those players who might support such interventions in collaboration with local financial institutions and other market players. (author)

2000-01-01

256

Comparison between full- and small-scale sensory assessments of air quality  

DEFF Research Database (Denmark)

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 glass chambers ventilated at an airflow of 0.9 L/s. Full-scale assessments were made immediately upon entering offices ventilated at an outdoor air supply rate of 1.9 h-1. The ratio of ventilation rate to surface area of a building material was identical in the chambers and in the offices. Full-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 the perceived air quality in spaces, sensory emission rates estimated in small scale may require a correction, probably depending on the nature of the chemicals emitted by a building material.

Wargocki, Pawel; Sabikova, J.

2002-01-01

257

Small-scale spatial patterns of meiobenthos in the Arctic deep sea  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A variety of analytical techniques were used to quantify and describe small-scale (centimetre to decimetre) spatial patterns of meiofauna taxa, with emphasis on nematode species, at a bathyal site in the Arctic deep sea. Three cores (10-cm diameter) taken from the same multicorer were each subsample...

Gallucci, F.; Moens, T.; Fonseca, G.

258

The relationship between small-scale care and activity involvement of residents with dementia.  

UK PubMed Central (United Kingdom)

BACKGROUND: Nursing home care for people with dementia is increasingly organized in small-scale care settings. This study focuses on the question of how small-scale care is related to the overall activity involvement of residents with dementia, and their involvement in different types of activities. As several studies have indicated, activity involvement is important for the quality of life of residents. METHODS: Data were derived from the first measurement cycle (2008/2009) of the Living Arrangements for people with Dementia study, in which 136 care facilities and 1,327 residents participated. The relationship between two indicators of small-scale dementia care (group living home care characteristics, and the total number of residents with dementia in the facility) and activity involvement (Activity Pursuit Patterns of the Resident Assessment Instrument Minimum Data Set) were studied with multilevel multiple regression analyses. All analyses were adjusted for the residents' age, sex, neuropsychiatric symptoms, and dependency on the activities of daily living. RESULTS: Residents of care facilities with more group living home care characteristics were more involved in overall and preferred activities. Furthermore, they were involved in more diverse activities. Overall, no relationship was found between the number of residents at the facility and activity involvement. CONCLUSIONS: These results indicate that small-scale dementia care has a positive effect on activity involvement of residents. The current study also sheds light on the lack of activity involvement of many residents with dementia, especially those who are older, male, and with higher dependency.

Smit D; de Lange J; Willemse B; Pot AM

2012-05-01

259

Evaluation of real-time operating system for small-scale embedded systems  

International Nuclear Information System (INIS)

In this paper, the performance of some real-time operating systems for small-scale embedded systems are evaluated based on some criteria. The evaluation is performed qualitatively and quantitatively. The evaluation results based on a case study on an engineering application will be presented. (author)

1999-01-01

260

Implementation of small scale hydroelectric power plants; Implantacao de pequenas centrais hidreletricas  

Energy Technology Data Exchange (ETDEWEB)

This work describes some aspects concerning the implementation of small scale hydroelectric power plants. The main aspects focused are the historic aspects of such units; the inventory of the potential of Sao Paulo State, Southeast Brazil; the optimization of the project; the participation of private enterprise; and case studies 3 tabs.

Hermann Junior, Jorge; Arruda Bueno, Gilberto de [Companhia Energetica de Sao Paulo, SP (Brazil)

1991-12-31

 
 
 
 
261

Air pollution and economics: Alternate use of fuels in small scale industries  

International Nuclear Information System (INIS)

In developing countries the problem of air pollution was recognized earlier, however, it has acquired a greater dimension due to the conventional use of low grade fuels like coal, baggase, rice husk, etc. having high sulphur and ash content. The industrial sources contribute about 30--40% of the total emissions. In India, the small scale industries (low investment group) contribute about 60--80% of the total industrial emissions. These industries are characterized with various environmental pollution problems due to cluster of small scale industries located in sensitive area; use of low grade fuel, primitive processing techniques without emission abatement facilities etc., thus leading to enormous pollution in an confined region. Acute need was felt to reduce the pollution problem associated with small scale industries by use of cleaner fuel so as to reduce the localized problem. The paper presents the emissions associated with use of coal/coke, natural gas, LPG, and propane along with the fuel cost for small scale industrial sector of Agra, Firozabad and Mathura region. The studies carried out would find applicability to meet the air pollution standards based on shift in fuel and associated cost

1999-01-01

262

Spectrum of the small-scale part of artificial ionospheric turbulence  

Energy Technology Data Exchange (ETDEWEB)

Experimental and theoretical results on artificial ionospheric turbulence (AIT) produced by radio frequency heating are discussed. It is shown that the sounding of disturbed regions of the ionosphere at various frequencies gives information on the development and relaxation of the small-scale part of the AIT. Information on the large-scale part of the turbulence can also be obtained.

Erukhimov, L.M.; Komrakov, G.P.; Frolov, V.L.

1980-11-01

263

A typical small-scale chlorine leak and dispersion simulation in industrial facilities  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The liquefied chlorine release is the most frequent accident in hazardous materials ( HAZMAT) releases. A typical small-scale accidental release of chlorine was simulated using a FLUENT code (CFD software). In addition, consequences of continuous and instantaneous release scenarios were investigat...

Li Jianfeng, Zhang Bin, Liu Wenmao

264

Direct observation of anomalous electron diffusion due to small-scale magnetic turbulence in a tokamak  

Energy Technology Data Exchange (ETDEWEB)

Nonclassical diffusion of test electrons was directly observed in a tokamak by examination of the radial broadening of their drift orbits. A strong correlation between this enhanced diffusion and small-scale radial magnetic field fluctuations of high poloidal mode number was found. The origin of these magnetic fluctuations is discussed in terms of microtearing mode.

Takamura, S.; Ohnishi, N.; Iwai, K.; Okuda, T.

1986-05-12

265

Small-scale hydroelectric power plants planning; Planejamento de centrais hidreletricas de pequeno porte  

Energy Technology Data Exchange (ETDEWEB)

This work discusses the small-scale hydroelectric power plants planning considering integrated systems and decentralized systems. Technical aspects and costs are analysed including energy demand factors. Other aspects are also considered such as electric power generation and distribution. Finally, institutional aspects and tariffs related to interconnection of decentralized and integrated systems are discussed. 182 refs., 73 figs., 41 tabs.

Santos, Afonso H.M.

1987-12-31

266

Development of a Small-Scale Natural Gas Liquefier. Final Report.  

Science.gov (United States)

Gas Technology Institute (GTI), with support from the U.S. Department of Energy (DOE) and Brookhaven National Lab, developed and tested a pre-commercial small-scale natural gas liquefaction system. This cryogenic technology has potential use in a variety ...

K. Kountz K. Kriha W. Liss M. Perry M. Richards

2003-01-01

267

Performance of a small scale prototype of cellular honeycomb proportional chamber  

CERN Document Server

Beam test results for the first small-scale prototype of a honeycomb cellular proportional chamber to be used in ALICE PMD are presented. The overall efficiency for MIP detection is found to be around 93%. The efficiency drops to about 75% at the corners of the hexagon. Improvement in design is suggested.

Ahammed, Z; CERN. Geneva; Bhati, A K; Chattopadhyay, S; Dubey, A K; Dutta Mazumdar, M R; Mahapatra, D P; Ganti, M S; Nayak, T K; Singaraju, R N; Trivedi, M D; Viyogi, Y P; Aggarwal, M M

1999-01-01

268

Harmonic Propagation and Interaction Evaluation between Small-Scale Wind Farms and Nonlinear Loads  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Distributed generation is a flexible and effective way to utilize renewable energy. The dispersed generators are quite close to the load, and pose some power quality problems such as harmonic current emissions. This paper focuses on the harmonic propagation and interaction between a small-scale wind...

Guang-Long Xie; Bu-Han Zhang; Yan Li; Cheng-Xiong Mao

269

Capacitation in small scale hydroelectric power plants; Capacitacao em pequenas centrais hidreletricas - PCH's  

Energy Technology Data Exchange (ETDEWEB)

This work presents a special program developed by the University of Amazonas, Amazonas state - North Brazil- to capacitate undergraduate students in small scale hydroelectric power plants issues. The subjects covered as well as assignments performed and field studies as well as visitations are described.

Martins, Geralda Maria

1990-04-01

270

Analysis of Stability, Response and LQR Controller Design of a Small Scale Helicopter Dynamics  

CERN Multimedia

This paper presents how to use feedback controller with helicopter dynamics state space model. A simplified analysis is presented for controller design using LQR of small scale helicopters for axial and forward flights. Our approach is simple and gives the basic understanding about how to develop controller for solving the stability of linear helicopter flight dynamics.

Dharmayanda, Hardian Reza; Lee, Young Jae; Sung, Sangkyung

2008-01-01

271

Small scale hybrid concentrated solar power - biomass system. Development, time dependent modelling and validation.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Proceeding from the sustainable development principle and the current energy issues, in the present work a small-scale fully renewable power plant was designed, modelled in a time-dependent environment and validated. The plant is design in order to produce both thermal and electric power either in o...

TORTORA, EILEEN

272

Relative Localization and Communication Module for Small-Scale Multi-Robot Systems  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We characterize and improve an existing infrared relative localization/communication module used to find range and bearing between robots in small-scale multi-robot systems. Modifications to the algorithms of the original system are suggested which offer better performance. A mathematical model wh...

Pugh, Jim; Martinoli, Alcherio

273

The response of a New Guinean avifauna to conversion of forest to small-scale agriculture  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In comparison with other tropical forest land uses such as selective logging, little is known of the impacts on wildlife of the many forms of small-scale agriculture practised across the tropics. We present density estimates, derived using a point count distance sampling method, for 31 bird species ...

Marsden, Stuart J.; Symes, Craig T.; Mack, Andrew L.

274

Irrigation water value at small-scale schemes : evidence from the North West Province, South Africa  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Insight into the value of water is essential to support policy decision making about investments in the water sector, efficient allocation of water and water pricing. However, information on irrigation water values at small-scale schemes is scarce and in general little attention is paid to the deter...

Speelman, Stijn; Farolfi, Stefano; Perret, S. (Sylvain); D'Haese, Luc; D'Haese, Marijke F.C.

275

The Use of Farm Information Systems among Grasscutter Farmers in Ga-South Municipality and Awutu-Senya District in Ghana  

Directory of Open Access Journals (Sweden)

Full Text Available The paper investigated farm information systems use among grasscutter farmers in Ga-South and Awutu-Senya District in Ghana. Using frequency, cross tabulations and binary logit model in Statistical Package for Social Sciences (SPSS) version 18, the study made some findings. Grasscutter farmers in the study area are ageing. They operate on small scale with males dominating the enterprise. The generally literate farmers used production records mostly. Farmers’ use of farm information systems did not show positive association with obtaining credit from formal credit institutions. The use of books and loose sheets to keep records of farm operations is most popular with the farmers. Use of computers is least popular. Too much work, no reasons for non-use, and inadequate time at their disposal to spare some for recording were some of the reasons adduced for not using farm information systems. Age, level of education, farm size, and farmer status, membership of association, sex, experience and income were found to be independent of farm information systems use. Government and non-governmental organisations must encourage young persons especially females to engage in the enterprise. An investigation into the causes of low farm size will unearth the causes and as such provide ways to increase farm size as most of the farmers are into full time grasscutter rearing. Members of grasscutter farmers association need to step up their membership drive to recruit more farmers into the association as associations are better to relate to and reach with extension effort.

Justice G. Djokoto

2012-01-01

276

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)

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.

2012-01-01

277

Glyphosate Exposure in a Farmer’s Family  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We tested the presence of glyphosate in the urines of a farmer who sprayed a glyphosate based herbicide on his land, and in his family, as his children were born with birth defects that could be due to or promoted by pesticides. Glyphosate residues were measured in urines a day before, during, and t...

Robin Mesnage; Christian Moesch; Rozenn Le Grand Grand; Guillaume Lauthier; Joël Spiroux de Vendômois; Steeve Gress

278

Adoption of Coccidiosis Vaccines by Poultry Farmers in Ijebu Area of Ogun State, Nigeria  

Directory of Open Access Journals (Sweden)

Full Text Available The paper focused on adoption of coccidiosis vaccines by poultry farmers in Ijebu-Area of Ogun State, Nigeria. Specifically, the poultry farmers selected personal characteristics such as age, sex, religion, marital status, educational attainment, farm income and sources of credit were identified Their level of awareness and adoption of the coccidiosis vaccines were also determined. The relationship between adoption and the selected personal characteristics was established. The relationship between adoption and constraints to adoption was also established. Eighty eight (88) poultry farmers were selected through a stratified sampling method from six (06) local government councils using a pre-tested Questionnaire. Examination of the poultry farmer's personal characteristics revealed that 80.7 percent were male and is between age-range of thirty-one and fifty years. Sixty seven (67) percent were Christians while 98.9 percent had formal education. Almost forty one percent (40.9%) reared between 500 and 1000 birds while 29.5 percent reared above 1000 birds with farm income ranging from 25,000 to above N50, 000 per month. 88.6% are aware of coccidiosis vaccines, 83 percent had adopted and immuncox® is the most commonly used (66.2%). The study revealed that age and sex were significantly related to adoption amongst other personal characteristics tested. The study also revealed that there is no significant relationship between adoption and constraints to adoption. Coccidiosis vaccines were found to have gained widespread acceptance among poultry farmers in Ijebu area of Ogun State, Nigeria. It was recommended that Unified Extension Agents in the area should facilitate the transfer of the technology and dissemination of information on coccidiosis vaccines to both small and medium poultry farmers in the study areas. There should also be effective extension services to small-scale commercial poultry farmers will enhance their productivity and eventually elevate them to large-scale level of production.

M.A. Oladoja; T.P. Olusanya

2007-01-01

279

THE ROMANIAN FARMERS' PRODUCTIVITY AND COMPETITIVENESS  

Directory of Open Access Journals (Sweden)

Full Text Available The relations between farmers’ productivity and competitiveness are evaluated; the causes of Romanian farmers’ productivity deficit are revealed, and on this basis possible solutions are proposed in order to consolidate the competitional position of agricultural holdings.

I. DAVIDOVICI; A. SAVA DAVIDOVICI; MIHAELA KRUZSLICIKA

2009-01-01

280

Farmers' Attitudes and Behavior toward Sustainable Agriculture.  

Science.gov (United States)

A mail survey of Iowa farmers with membership in Practical Farmers of Iowa (PFI), a sustainable agriculture organization, was used to examine the attitude-behavior relationship of these farmers and the role social influences played in this relationship. Results indicate that when controlling explanatory factors, the attitude-behavior relationship…

Petrzelka, Peggy; Korsching, Peter F.; Malia, James E.

1996-01-01

 
 
 
 
281

Small-scale disequilibrium in a magmatic inclusion and its more silicic host  

Science.gov (United States)

An investigation of small-scale isotopic, compositional, and mineralogical variation across the interface of a basaltic-andesite inclusion and its dacitic host from Cerro-Chascon, a Holocene dome in northern Chile, is discussed. Serial sectioning across the interface of the inclusion and its host dacite, complemented by microdrill sampling and detailed microprobe work, has enabled an examination of the scale of mixing and chemical disequilibrium. The composition of the inclusion is found to be relatively homogeneous; the dacite host is heterogeneous on a small scale; the isotopic composition in the marginal zone shows the highest Sr-87/Sr-86 and lowest Nd-143/Nd-144; the large plagioclase crystals in the inclusions and host are xenocrystic. These differences are reconciled with a model of magma evolution in a crustal magma chamber.

Davidson, Jon P.; Holden, Peter; Halliday, Alex N.; de Silva, Shanaka L.

1990-10-01

282

Entirely renewable energy-based electricity supply system (small scale and large scale)  

Energy Technology Data Exchange (ETDEWEB)

Our future energy needs will be supplied by a combination of many different sources ranging from small wind turbine to provide power for a single house to central power stations that provide power in very large scale fed into the national grid. Computer control systems will integrate the performance of all these systems to make sure that as much power as possible comes from environmentally friendlier sources. As alternative sources becomes more widely available, small scale systems meeting local needs may start to replace current large scale central power stations. The author is investigating the feasibility of an entirely renewable energy-based electricity supply system. The developed system find so many applications as it can be used as small scale power system for Remote Area Power Supply, wind energy/battery or solar energy/battery, as well as large scale for interconnection with national grid. (Author)

Zahedi, A. [Monash University, Caulfield (Australia). Division of Electrical and Computer Systems Engineering

1996-09-01

283

Social welfare as small-scale help: evolutionary psychology and the deservingness heuristic.  

UK PubMed Central (United Kingdom)

Public opinion concerning social welfare is largely driven by perceptions of recipient deservingness. Extant research has argued that this heuristic is learned from a variety of cultural, institutional, and ideological sources. The present article provides evidence supporting a different view: that the deservingness heuristic is rooted in psychological categories that evolved over the course of human evolution to regulate small-scale exchanges of help. To test predictions made on the basis of this view, a method designed to measure social categorization is embedded in nationally representative surveys conducted in different countries. Across the national- and individual-level differences that extant research has used to explain the heuristic, people categorize welfare recipients on the basis of whether they are lazy or unlucky. This mode of categorization furthermore induces people to think about large-scale welfare politics as its presumed ancestral equivalent: small-scale help giving. The general implications for research on heuristics are discussed.

Petersen MB

2012-01-01

284

Initial Market Assessment for Small-Scale Biomass-Based CHP  

Energy Technology Data Exchange (ETDEWEB)

The purpose of this report is to reexamine the energy generation market opportunities for biomass CHP applications smaller than 20 MW. This paper provides an overview of the benefits of and challenges for biomass CHP in terms of policy, including a discussion of the drivers behind, and constraints on, the biomass CHP market. The report provides a summary discussion of the available biomass supply types and technologies that could be used to feed the market. Two primary markets are outlined--rural/agricultural and urban--for small-scale biomass CHP, and illustrate the primary intersections of supply and demand for those markets. The paper concludes by summarizing the potential markets and suggests next steps for identifying and utilizing small-scale biomass.

Brown, E.; Mann, M.

2008-01-01

285

Shaken, but not stirred: how vortical flow drives small-scale aggregations of gyrotactic phytoplankton  

Science.gov (United States)

Coastal ocean observations reveal that motile phytoplankton form aggregations at the Kolmogorov scale (mm-cm), whereas non-motile cells do not. We propose a new mechanism for the formation of this small-scale patchiness based on the interplay of turbulence and gyrotactic motility. Counterintuitively, turbulence does not stir a plankton suspension to homogeneity but drives aggregations instead. Through controlled laboratory experiments we show that the alga Heterosigma akashiwo rapidly forms aggregations in a cavity-driven vortical flow that approximates Kolmogorov eddies. Gyrotactic motility is found to be the key ingredient for aggregation, as non-motile cells remain randomly distributed. Observations are in remarkable agreement with a 3D model, and the validity of this mechanism for generating patchiness has been extended to realistic turbulent flows using Direct Numerical Simulations. Because small-scale patchiness influences rates of predation, sexual reproduction, infection, and nutrient competition, this result indicates that gyrotactic motility can profoundly affect phytoplankton ecology.

Barry, Michael; Durham, William; Climent, Eric; Stocker, Roman

2011-11-01

286

Active damping control unit using a small scale proof mass electrodynamic actuator.  

UK PubMed Central (United Kingdom)

This paper presents a study on the design and use of a small scale proof mass electrodynamic actuator, with a low mounting resonance frequency, for velocity feedback control on a thin rectangular panel. A stability-performance formula is derived, which can be effectively used to assess the down scaling effects on the stability and control performance of the feedback loop. The design and tests of a velocity feedback loop with a prototype small scale proof mass actuator are also presented. When a feedback control having a gain margin of about 6 dB is implemented, so that there is little control spillover effect around the fundamental resonance of the actuator, reductions of vibration between 5 dB and 10 dB in the frequency band between 80 Hz and 250 Hz have been measured at the control position.

González Díaz C; Paulitsch C; Gardonio P

2008-08-01

287

Small scale magnetic field evolution in the first objects formed in the universe  

Scientific Electronic Library Online (English)

Full Text Available Abstract in english Large scale magnetic fields in galaxies are thought to be generated, by a mean field dynamo. In order to have generated the fields observed, the dynamo would have had to have operated for a sufficiently long period of time. However, magnetic fields of similar intensities to the one in our galaxy, are observed in high redshift galaxies, where a mean field dynamo would not have had time to produce the observed fields. MHD turbulence produces small scale magnetic fields at a (more) faster rate than it does mean fields, which can diffuse toward larger scales. If the turbulence is helical, magnetic fields generated at small scales can become correlated over large scales. We study the evolution of magnetic field correlations in the first objects formed in the universe, due to the action of a turbulent, helical, stochastic dynamo, for redshifts 5

Kandus, Alejandra; Opher, Reuven; Barros, Saulo M. R.

2004-12-01

288

Several small-scale vector array performance analysis and simulation of DOA estimation  

Science.gov (United States)

To research the application and estimate performance in some small-scale vector sensor array by traditional direction of arrival estimate , we derivate the time delay expression of four small-scale non-uniform vector sensor array, the array direction vector is given, and the MUSIC algorithm is applied successfully to non-uniform vector array for direction of arrival(DOA) estimate, select the better performance of each array element setting method, and compare of beam forming, the probability of success and the mean square error, this shows that the performance of line array is best, followed by L-array and circular array, the performance of cross-array is worst.

Mei, Yinzhen

2011-10-01

289

Energy transfers and magnetic energy growth in small-scale dynamo  

CERN Multimedia

In this letter we investigate the dynamics of magnetic energy growth in small-scale dynamo by studying energy transfers, mainly energy fluxes and shell-to-shell energy transfers. We perform dynamo simulation for magnetic Prandtl number $\\mathrm{Pm}=20$ on $1024^3$ grid using pseudospectral method. We demonstrate using flux and shell-to-shell energy transfer computations that the magnetic energy growth is caused by nonlocal energy transfers from the large scale velocity field to small scale magnetic field. The energy transfers $U2U$ (velocity to velocity) and $B2B$ (magnetic to magnetic) are forward and local. We also show that the magnetic energy grows exponentially with time, and it tends to have equipartition with kinetic energy.

Kumar, Rohit; Samtaney, Ravi

2013-01-01

290

Small scale effect on elastic buckling of carbon nanotubes with nonlocal continuum models  

International Nuclear Information System (INIS)

Nonlocal elastic beam and shell models are developed and applied to investigate the small scale effect on buckling analysis of carbon nanotubes (CNTs) under compression. General and explicit solutions are derived and expressed in terms of the solutions via local or classical elastic models, in which the scale effect is not accounted, to reveal the small scale effect on CNTs buckling results. The dependence of the scale effect with respect to the length, radius, and buckling modes of CNTs is clearly established and observed from the universal solutions derived in the manuscript. It is clearly seen from the results that the buckling solutions for CNTs via local continuum mechanics are overestimated and hence the scale effect is indispensable in providing more accurate results for mechanical behaviors of CNTs via continuum mechanics.

2006-09-04

291

Automated small-scale fuel alcohol plant: A means to add value to food processing waste  

Energy Technology Data Exchange (ETDEWEB)

A small scale fuel grade alcohol plant was designed, constructed and operated a decade ago. This plant design incorporated several innovative processes and features that are still on the cutting edge for small scale alcohol production. The plant design could be scaled down or up to match the needs of food processing waste streams that contain sugars or starches as BOD. The novel features include automation requiring four hours of labor per 24 hour day and a plug flow low temperature cooking system which solubilizes and liquifies the starch in one step. This plant consistently produced high yield of alcohol. Yields of 2.6 gallons of absolute alcohol were produced from a bushel of corn. Potato waste grain dust and cheese whey were also processed in this plant as well as barley. Production energy for a 190 proof gallon was approximately 32,000 BTU. This paper discusses the design, results, and applicability of this plant to food processing industries.

Wolfram, J.H.; Keller, J. [Idaho National Engineering Lab., Idaho Falls, ID (United States); Wernimont, L.P.

1993-12-31

292

Numerical simulation of the interaction between solar granules and small-scale magnetic fields  

CERN Multimedia

We have carried out numerical simulation based on the equations of radiation magnetohydrodynamics to study the interaction of solar granules and small-scale magnetic fields in photospheric regions with various magnetic fluxes. Four sequences of 2D time-dependent models were calculated for photospheric regions with average vertical magnetic fluxes of 0, 10, 20, and 30 mT. The models exhibit no substantial variations in their temperature structure with varying average field strength, while the density and gas pressure profiles display gross changes. The solar granulation brightness field also varies substantially with magnetic flux. The contribution of the small-scale component to the intensity power spectrum increases with average field strength, whereas the large-scale component (of about a granule size) contributes less, the total rms intensity fluctuations being approximately the same. Thus the observed decrease in rms intensity fluctuations with growing average magnetic flux can be interpreted as smoothing...

Atroshchenko, I N

2010-01-01

293

Pressure swing adsorption for small-scale on-site hydrogen supply  

International Nuclear Information System (INIS)

[en] Pressure swing adsorption (PSA) is a technology that has been used for a long time for medium and large scale purification of hydrogen. Up to the present, this technology has not been considered suitable for use in smaller scale markets due to the complexity of conventional pressure swing adsorption systems. This paper describes a simplified version of PSA hardware developed by Highquest Engineering and Questor Industries of Vancouver. It is capable of overcoming earlier objections with regard to use in small scale purification projects. Test results from the HyQuestor 605 commercial PSA unit show that high purity, productivity and recovery can be achieved with the Questor systems in small scale hydrogen streams from a variety of sources. Moreover, since the technology is modular in design, it is upwardly expandable to handle higher hydrogen flows for petroleum refining and other applications such as compressed hydrogen refueling for fuel cell propelled vehicles. 11 refs. 6 tabs

1997-01-01

294

Pressure swing adsorption for small-scale on-site hydrogen supply  

Energy Technology Data Exchange (ETDEWEB)

Pressure swing adsorption (PSA) is a technology that has been used for a long time for medium and large scale purification of hydrogen. Up to the present, this technology has not been considered suitable for use in smaller scale markets due to the complexity of conventional pressure swing adsorption systems. This paper describes a simplified version of PSA hardware developed by Highquest Engineering and Questor Industries of Vancouver. It is capable of overcoming earlier objections with regard to use in small scale purification projects. Test results from the HyQuestor 605 commercial PSA unit show that high purity, productivity and recovery can be achieved with the Questor systems in small scale hydrogen streams from a variety of sources. Moreover, since the technology is modular in design, it is upwardly expandable to handle higher hydrogen flows for petroleum refining and other applications such as compressed hydrogen refueling for fuel cell propelled vehicles. 11 refs. 6 tabs.

McLean, C. R. [Questor Industries Inc., Vancouver, BC (Canada); Keefer, B. G. [Highquest Engineering, Inc., Vancouver, BC (Canada); Rowat, D. W. [Strategic Catalysts Inc., Vancouver, BC (Canada)

1997-05-01

295

First Results from Viper Detection of Small-Scale Anisotropy at 40 GHZ  

CERN Multimedia

Results of a search for small-scale anisotropy in the cosmic microwave background (CMB) are presented. Observations were made at the South Pole using the Viper telescope, with a .26 degree (FWHM) beam and a passband centered at 40 GHz. Anisotropy band-power measurements in bands centered at l = 108, 173, 237, 263, 422 and 589 are reported. Statistically significant anisotropy is detected in all bands.

Peterson, J B; Newcomb, M G; Alvarez, D L; Cantaloupo, C; Morgan, D; Miller, K W; Ganga, K; Pernic, D; Thoma, M H

1999-01-01

296

The Viper Telescope : an Instrument to Measure Primary and Secondary CMB Anisotropy at Small Scales  

Science.gov (United States)

Viper is a 2-meter off-axis telescope designed to measure small-scale anisotropy in the Cosmic Microwave Background Radiation. It is currently deployed at the South Pole, operating with a 40 GHz HEMT receiver. We are attempting to measure primary anisotropy in addition to secondary anistropy from the Sunyaev-Zeldovich (S-Z) effect. Preliminary data will be presented, along with a description of plans for future cosmological and non-cosmological observations.

Griffin, G.; Peterson, J.; Romer, K.; Alvarez, D.; Cantalupo, C.; Morgan, D.; Newcomb, M.; Vincent, M.; Miller, K.; Novak, G.; Dragovan, M.; Crone, B.

1998-05-01

297

Small-Scale High Temperature Melter-1 (SSHTM-1) Data Package. Appendix A  

International Nuclear Information System (INIS)

This appendix provides the data for Alternate HTM Flowsheet 1 (No Reductant Addition, Nitric Acid) melter feed preparation activities in both the laboratory and small-scale testing. The first section provides an outline of this appendix. The melter feed preparation data are presented in the next two main sections, laboratory welter feed preparation data and small-scale melter feed preparation data. Section 3.0 provides the laboratory data which is discussed in the main body of the Small-Scale High Temperature-1 (SSHTM-1) Data Package, milestone C95-02.02Y. Section 3.1 gives the flowsheet in outline form as used in the laboratory-scale tests. This section also includes the ''Laboratory Melter Feed Preparation Activity Log'' which gives a chronological account of the test in terms of time, temperature, slurry pH, and specific observations about slurry appearance, acid addition rates, and samples taken. The ''Laboratory Melter Feed Preparation Activity Log'' provides a road map to the reader by which all the activity and data from the laboratory can be easily accessed. A summary of analytical data is presented next, section 3.2, which covers starting materials and progresses to the analysis of the melter feed. The next section, 3.3, characterizes the off-gas generation that occurs during the slurry processing. The following section, 3.4, provides the rheology data gathered including gram waste oxide loading information for the various slurries tested. The final section, 3.5. includes data from standard crucible redox testing. Section 4.0 provides the small-scale data tn parallel form to section 3.0. Section 5.0 concludes with the references for this appendix.

1996-01-01

298

Small-Scale High Temperature Melter-1 (SSHTM-1) Data Package. Appendix B  

Energy Technology Data Exchange (ETDEWEB)

This appendix provides the data for Alternate HTM Flowsheet 2 (Glycolic Acid) melter feed preparation activities in both the laboratory- and small-scale testing. The first section provides an outline of this appendix. The melter feed preparation data are presented in the next two main sections, laboratory melter feed preparation data and small-scale melter feed preparation data. Section 3.0 provides the laboratory data which is discussed in the main body of the Small-Scale High Temperature-1 (SSHTM-1) Data Package, milestone C95-02.02Y. Section 3.1 gives the flowsheet in outline form as used in the laboratory-scale tests. This section also includes the ``Laboratory Melter Feed Preparation Activity Log`` which gives A chronological account of the test in terms of time, temperature, slurry pH, and specific observations about slurry appearance, acid addition rates, and samples taken. The ``Laboratory Melter Feed Preparation Activity Log`` provides a road map to the reader by which all the activity and data from the laboratory can be easily accessed. A summary of analytical data is presented next, section 3.2, which covers starting materials and progresses to the analysis of the melter feed. The next section, 3.3, characterizes the off-gas generation that occurs during the slurry processing. The following section, 3.4, provides the rheology data gathered including gram waste oxide loading information for the various slurries tested. The final section, 3.5, includes data from standard crucible redox testing. Section 4.0 provides the small-scale data in parallel form to section 3.0. Section 5.0 concludes with the references for this appendix.

NONE

1996-03-01

299

Small-Scale High Temperature Melter-1 (SSHTM-1) Data Package. Appendix A  

Energy Technology Data Exchange (ETDEWEB)

This appendix provides the data for Alternate HTM Flowsheet 1 (No Reductant Addition, Nitric Acid) melter feed preparation activities in both the laboratory and small-scale testing. The first section provides an outline of this appendix. The melter feed preparation data are presented in the next two main sections, laboratory welter feed preparation data and small-scale melter feed preparation data. Section 3.0 provides the laboratory data which is discussed in the main body of the Small-Scale High Temperature-1 (SSHTM-1) Data Package, milestone C95-02.02Y. Section 3.1 gives the flowsheet in outline form as used in the laboratory-scale tests. This section also includes the ``Laboratory Melter Feed Preparation Activity Log`` which gives a chronological account of the test in terms of time, temperature, slurry pH, and specific observations about slurry appearance, acid addition rates, and samples taken. The ``Laboratory Melter Feed Preparation Activity Log`` provides a road map to the reader by which all the activity and data from the laboratory can be easily accessed. A summary of analytical data is presented next, section 3.2, which covers starting materials and progresses to the analysis of the melter feed. The next section, 3.3, characterizes the off-gas generation that occurs during the slurry processing. The following section, 3.4, provides the rheology data gathered including gram waste oxide loading information for the various slurries tested. The final section, 3.5. includes data from standard crucible redox testing. Section 4.0 provides the small-scale data tn parallel form to section 3.0. Section 5.0 concludes with the references for this appendix.

Smith, G.L.

1996-03-01

300

A novel one step approach to small scale labeling of organic compounds with hydrogen isotopes  

Energy Technology Data Exchange (ETDEWEB)

A rapid method to generate tritium gas for small scale labeling is described. Tritium labelled sodium borohydride is used with cobalt (II) chloride to generate isotopic hydrogen gas. The reaction was carried out in a closed vessel and three different compounds were concurrently labelled. This simple and inexpensive method can be applied to a broad range of molecules and does not require any special set up. (author).

Malik, S.; Kenny, M. (Washington Univ., Seattle, WA (United States). Dept. of Medicine); Doss, G.; Varghese, J. (Stanford Univ., CA (United States). Dept. of Chemistry)

1994-05-01

 
 
 
 
301

Costs for renewable electricity. Small-scale self-supporting biomass installations  

International Nuclear Information System (INIS)

The aim of the study on the title subject is to provide an objective basis for the determination of the assumptions that are used for the calculation of the so-called uneconomic top of electricity production from renewable energy sources, carried out by ECN and KEMA. The results will be used for the determination of the subsidy tariffs for small-scale self-supporting biomass installations and is part of the Environmental Quality of Electricity Production (MEP, abbreviated in Dutch) policy

2003-01-01

302

Summary Report on FY12 Small-Scale Test Activities High Temperature Electrolysis Program  

Energy Technology Data Exchange (ETDEWEB)

This report provides a description of the apparatus and the single cell testing results performed at Idaho National Laboratory during January–August 2012. It is an addendum to the Small-Scale Test Report issued in January 2012. The primary program objectives during this time period were associated with design, assembly, and operation of two large experiments: a pressurized test, and a 4 kW test. Consequently, the activities described in this report represent a much smaller effort.

James O' Brien

2012-09-01

303

Small-scale heterogeneity in deep-sea nematode communities around biogenic structures.  

UK PubMed Central (United Kingdom)

The unexpected high species richness of deep-sea sediments gives rise to the questions, which processes produce and maintain diversity in the deep sea, and at what spatial scales do these processes operate? The idea of a small-scale habitat structure at the deep-sea floor provides the background for this study. At small scales biogenic structures create a heterogeneous environment that influences the structure of the surrounding communities and the dynamics of the meiobenthic populations. As an example for biogenic structures, small deep-sea sponges (Tentorium semisuberites Schmidt 1870) and their sedimentary environment were investigated for small-scale distribution patterns of benthic deep-sea nematodes. Sampling was carried out with the remotely operated vehicle Victor 6000 at the Arctic deep-sea observatory HAUSGARTEN. In order to investigate nematode community patterns sediment cores around three small sponges and corresponding control cores were analysed. A total of approx. 5800 nematodes were identified. The comparison of the nematode communities from sponge and control samples indicated an influence of the biogenic structure "sponge" on diversity patterns and habitat heterogeneity. The increased number of nematode species and functional groups found in the sediments around the sponges suggest that on a small scale the sponge acts as a gradient and creates a more divers habitat structure. The nematode community from the sponge sediments shows a greater taxonomic variance and species richness together with lower relative abundances of the species compared to those from control sediments. Obviously, the more homogeneous habitat conditions of the control sediments offer less micro-habitats than the sediments around the sponges. This seems to reduce the number of functional groups and species coexisting in the control sediments.

Hasemann C; Soltwedel T

2011-01-01

304

Search for small-scale anisotropy in the cosmic microwave background  

Energy Technology Data Exchange (ETDEWEB)

A search for small-scale anisotropy in the cosmic microwave background has been conducted with the 140-ft telescope at Green Bank, West Virginia, operating at a frequency of 19.5 GHz. The half-power beamwidth was 1.5 arc minutes. A 95%-confidence upper limit of ..delta..T/T<1.1 x 10/sup -4/ was set on fluctuations on this scale.

Uson, J.M.; Wilkinson, D.T.

1982-11-08

305

Assessment of biosecurity practices of small-scale broiler producers in central Egypt.  

UK PubMed Central (United Kingdom)

In the current situation of endemicity of highly pathogenic avian influenza (HPAI) in Egypt, improving the biosecurity of poultry production has become essential to the progressive reduction the incidence of the disease. A significant proportion of the Egyptian commercial poultry system consists of small-scale poultry producers operating with low to minimal biosecurity measures. An investigation was conducted into the level of adoption of standard biosecurity measures of the small-scale commercial chicken growers, including both farm- and home-based commercial production, input suppliers and other actors along the meat chicken value chain in Fayoum, Egypt. The study which used direct observations and group discussions of nearly 160 participants and structured interviews with 463 respondents, assessed biosecurity implementation to improve management practices and ultimately to control and prevent highly pathogenic avian influenza (HPAI). The survey found that overall, biosecurity measures are rarely implemented in small-scale commercial poultry production units. Compliance with recommended biosecurity practices did not greatly vary from home-based to farm-based commercial production. Furthermore, serious risk practices were identified, such as unsafe disposal of poultry carcasses and potential disease spread posed by poor biosecurity measures implemented during vaccination. HPAI control measures have been ineffective due to limited cooperation between public and private sector, aggravated by the unpopular measures taken in the event of outbreaks and no compensation paid for incurred losses. Outreach and biosecurity awareness raising initiatives should be specifically developed for small-scale producers with the objective of improving general poultry management and thus preventing HPAI and other poultry diseases.

Negro-Calduch E; Elfadaly S; Tibbo M; Ankers P; Bailey E

2013-06-01

306

Natural Regeneration of Common Beech (Fagus sylvatica L.) Stands Using Small Scale Shelterwood System  

Directory of Open Access Journals (Sweden)

Full Text Available A number of practical examples of small scale natural regeneration of common beech were investigated in the period 2006–2010. In Croatia, the research area consisted of forest administrations of Zagreb, Koprivnica, Karlovac, Plitvice Lakes National Park and Žumberak – Samoborsko Gorje Nature Park, and outside Croatia it included Belgium, Czech Republic, Germany, Slovakia and Slovenia (Fig. 1). This paper presents the results of research into small scale regeneration of common beech in the form of groups (Fig. 2, Table 1), using the example of a Dinaric montane beech forest (as. Lamio orvalae-Fagetum /Ht. 1938/ Borhidi 1963) and small-stand regeneration, using the example of a beech forest with sedge (as. Carici pilosae-Fagetum Oberforfer 1957).Natural regeneration in virgin beech stands begins in the form of clusters and groups (Fig. 3 and 4, Table 2). This regeneration method can be applied in special purpose forests and in protection forests, since it forms structurally diverse stands that will satisfy non-market forest goods and services of these forests. It is also suitable for private forest owners because not only does it enable the concentration of treatments in small areas, but also allows the planning of a continuous yield.Small scale regeneration with shelterwood cuts in large complexes of managed forests is both possible and desirable. Regeneration over small areas at the level of small (1–3 ha) and medium (3–5 ha) stands has proven successful (Fig. 5, Table 3).Compared with classical regular management over large areas, small scale management is a closer-to-nature and more intensive management method. It requires the construction of a silvicultural plan that contains a map of initial regeneration gaps and directions of its expansion. Silvicultural treatments are applied simultaneously, but in different parts of the regeneration area. This type of management alleviates the application and supervision of silvicultural treatments and enables long-term and continuous planning of the felling cut.

Igor Ani?; Stjepan Mikac

2011-01-01

307

HNS-I small-scale gap-test acceptance-criteria investigation  

Energy Technology Data Exchange (ETDEWEB)

HNS-I small scale gap tests were conducted at three densities to determine the effect of density on gap sensitivity and the reproducibility of the gap test. Density was found to have a lower effect on sensitivity than the existing HNS-I acceptance region indicates. The reproducibility of the gap test was determined to be +- 0.21 db at a 95% confidence level.

Demerson, E.L.

1982-12-01

308

Compensation for small-scale phase distortions using a Fourier phase corrector  

Energy Technology Data Exchange (ETDEWEB)

It is demonstrated experimentally that efficient compensation for small-scale phase distortions of a CO/sub 2/ laser waverfront can be achieved by using a Zernike cell type of wavefront-reversal system. After passing twice through the phase plate the Strehl number of the beam increases from 0.43 to 0.86 due to the compensation. The main factors determining the quality of the compensation for the distortions are discussed.

Kliment' ev, S.I.; Kononov, V.V.; Kuprenyuk, V.I.; Smirnova, L.D.; Sergeev, V.V.; Sherstobitov, V.E.

1985-12-01

309

Development of small scale soft x-ray lasers: Aspects of data interpretation  

International Nuclear Information System (INIS)

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. Some aspects of data interpretation and gain measurements in such systems are discussed. 11 refs., 11 figs.

1990-01-01

310

Development of small scale soft x-ray lasers: Aspects of data interpretation  

Energy Technology Data Exchange (ETDEWEB)

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. Some aspects of data interpretation and gain measurements in such systems are discussed. 11 refs., 11 figs.

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

1990-02-01

311

Hydroelectric power plants. Small-scale plants. Wasserkraftanlagen. Klein- und Kleinstkraftwerke  

Energy Technology Data Exchange (ETDEWEB)

Small-scale power plants in the range below 500 kW make an important contribution to power generation. The book contains practical information on hydroelectric power plants, criteria for turbine selection, electric equipment, and the Ossberger turbine. Problems concerning taxation and energy and water legislation are gone into. Also discussed are economic criteria during acquisition, new construction, and modernisation for the purpose of electric power generation and grid power supply. (DG) With 149 figs.

Palffy, S.O.; Nowotny, G.; Partzsch, P.; Pucher, E.; Roemer, K.H.; Schlimgen, W.; Tratz, D.; Walcher, H.

1991-01-01

312

Fuzzy logic and its possibility using in automation of small-scale hydroelectric power plants regulation  

International Nuclear Information System (INIS)

The paper explains how can computer understand and process inaccurate (indefinite) information. It is processing of terms like e.g. 'around in the middle of month' or 'not too big'. Fuzzy logic, fuzzy sets, operations with them, fuzzy rules and using of linguistics variables are explained. The possibilities of application of fuzzy systems in automation of regulation of small-scale hydro power plants are discussed. (author)

2004-01-01

313

Small-Scale High Temperature Melter-1 (SSHTM-1) Data Package. Appendix B  

International Nuclear Information System (INIS)

This appendix provides the data for Alternate HTM Flowsheet 2 (Glycolic Acid) melter feed preparation activities in both the laboratory- and small-scale testing. The first section provides an outline of this appendix. The melter feed preparation data are presented in the next two main sections, laboratory melter feed preparation data and small-scale melter feed preparation data. Section 3.0 provides the laboratory data which is discussed in the main body of the Small-Scale High Temperature-1 (SSHTM-1) Data Package, milestone C95-02.02Y. Section 3.1 gives the flowsheet in outline form as used in the laboratory-scale tests. This section also includes the ''Laboratory Melter Feed Preparation Activity Log'' which gives A chronological account of the test in terms of time, temperature, slurry pH, and specific observations about slurry appearance, acid addition rates, and samples taken. The ''Laboratory Melter Feed Preparation Activity Log'' provides a road map to the reader by which all the activity and data from the laboratory can be easily accessed. A summary of analytical data is presented next, section 3.2, which covers starting materials and progresses to the analysis of the melter feed. The next section, 3.3, characterizes the off-gas generation that occurs during the slurry processing. The following section, 3.4, provides the rheology data gathered including gram waste oxide loading information for the various slurries tested. The final section, 3.5, includes data from standard crucible redox testing. Section 4.0 provides the small-scale data in parallel form to section 3.0. Section 5.0 concludes with the references for this appendix.

1996-01-01

314

Assessment of biosecurity practices of small-scale broiler producers in central Egypt.  

Science.gov (United States)

In the current situation of endemicity of highly pathogenic avian influenza (HPAI) in Egypt, improving the biosecurity of poultry production has become essential to the progressive reduction the incidence of the disease. A significant proportion of the Egyptian commercial poultry system consists of small-scale poultry producers operating with low to minimal biosecurity measures. An investigation was conducted into the level of adoption of standard biosecurity measures of the small-scale commercial chicken growers, including both farm- and home-based commercial production, input suppliers and other actors along the meat chicken value chain in Fayoum, Egypt. The study which used direct observations and group discussions of nearly 160 participants and structured interviews with 463 respondents, assessed biosecurity implementation to improve management practices and ultimately to control and prevent highly pathogenic avian influenza (HPAI). The survey found that overall, biosecurity measures are rarely implemented in small-scale commercial poultry production units. Compliance with recommended biosecurity practices did not greatly vary from home-based to farm-based commercial production. Furthermore, serious risk practices were identified, such as unsafe disposal of poultry carcasses and potential disease spread posed by poor biosecurity measures implemented during vaccination. HPAI control measures have been ineffective due to limited cooperation between public and private sector, aggravated by the unpopular measures taken in the event of outbreaks and no compensation paid for incurred losses. Outreach and biosecurity awareness raising initiatives should be specifically developed for small-scale producers with the objective of improving general poultry management and thus preventing HPAI and other poultry diseases. PMID:23218658

Negro-Calduch, E; Elfadaly, S; Tibbo, M; Ankers, P; Bailey, E

2012-12-04

315

Probing the inflaton: Small-scale power spectrum constraints from measurements of the CMB energy spectrum  

CERN Multimedia

In the early Universe, energy stored in small-scale density perturbations is quickly dissipated by Silk-damping, a process that inevitably generates mu- and y-type spectral distortions of the cosmic microwave background (CMB). These spectral distortions depend on the shape and amplitude of the primordial power spectrum at wavenumbers k < 10^4 Mpc^{-1}. Here we study constraints on the primordial power spectrum derived from COBE/FIRAS and forecasted for PIXIE. We show that measurements of mu and y impose strong bounds on the integrated small-scale power, and we demonstrate how to compute these constraints using k-space window functions that account for the effects of thermalization and dissipation physics. We show that COBE/FIRAS places a robust upper limit on the amplitude of the small-scale power spectrum. This limit is about three orders of magnitude stronger than the one derived from primordial black holes in the same scale range. Furthermore, this limit could be improved by another three orders of magn...

Chluba, Jens; Ben-Dayan, Ido

2012-01-01

316

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

Energy Technology Data Exchange (ETDEWEB)

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.

Balk, Thomas

2012-07-27

317

Design, construction, operation, and costs of a modern small-scale fuel-alcohol plant  

Energy Technology Data Exchange (ETDEWEB)

The design used for the Small-Scale Fuel Alcohol Plant (SSFAP) has overcome the major drawbacks of small-scale ethanol production, which are high labor requirements, batch operation, inefficient energy use, and low yields. By incorporating a microprocessor into the plant design, most plant operations have been automated and labor requirements have been reduced. Continuous processing has made energy conservation possible, thus reducing energy requirements. A low-temperature, continuous plug-flow cooker design has made high yields possible. Ethanol has been consistently produced at the SSFAP from corn at a yield of 2.6 gallons (anhydrous) per bushel and an energy requirement of 30,000 to 35,000 Btu/gallon (190-proof). In addition, barley, grain dust, and potato waste have been converted at the SSFAP. The capacity of the SSFAP is 180,000 gallons per year (300 days operation). Competitively priced ethanol is produced at this capacity. DOE intends that the SSFAP design be used as the reference design for small-scale ethanol production.

Leeper, S.A.; Dawley, L.J.; Wolfram, J.H.; Berglund, G.R.; Richardson, J.G.; McAtee, R.E.

1982-01-01

318

The Opacity of the Intergalactic Medium during Reionization: Resolving Small-scale Structure  

Science.gov (United States)

Early in the reionization process, the intergalactic medium (IGM) would have been quite inhomogeneous on small scales, due to the low Jeans mass in the neutral IGM and the hierarchical growth of structure in a cold dark matter universe. This small-scale structure acted as an important sink during the epoch of reionization, impeding the progress of the ionization fronts that swept out from the first sources of ionizing radiation. Here we present results of high-resolution cosmological hydrodynamics simulations that resolve the cosmological Jeans mass of the neutral IGM in representative volumes several Mpc across. The adiabatic hydrodynamics we follow are appropriate in an unheated IGM, before the gas has had a chance to respond to the photoionization heating. Our focus is determination of the resolution required in cosmological simulations in order to sufficiently sample and resolve small-scale structure regulating the opacity of an unheated IGM. We find that a dark matter particle mass of m dm ~ 1 Mpc are required. With our converged results we show how the mean free path of ionizing radiation and clumping factor of ionized hydrogen depend on the ultraviolet background flux and redshift. We find, for example at z = 10, clumping factors typically of 10-20 for an ionization rate of ? ~ (0.3-3) × 10-12 s-1, with corresponding mean free paths of ~3-15 Mpc, extending previous work on the evolving mean free path to considerably smaller scales and earlier times.

Emberson, J. D.; Thomas, Rajat M.; Alvarez, Marcelo A.

2013-02-01

319

Onset of small-scale turbulent dynamo at low magnetic Prandtl numbers  

CERN Document Server

We study numerically the dependence of the critical magnetic Reynolds number Rm_c for the turbulent small-scale dynamo on the hydrodynamic Reynolds number Re. We are interested in the regime of low magnetic Prandtl number Pm=Rm/Reconst as Re->infinity (small-scale dynamo exists at low Pm) or Rmc/Re=Pm_c->const as Re->infinity (no small-scale dynamo at low Pm). Results obtained in two independent sets of simulations of MHD turbulence using two different codes are brought together and found to be in quantitative agreement. We find that, at currently accessible resolutions, Rm_c grows with Re with no sign of approaching a constant limit. We reach the maximum value of Rm_c~500$ for Re~3000. By comparing simulations with Laplacian viscosity, 4th- to 8th-order hyperviscosity, and Smagorinsky large-eddy viscosity, we find that Rm_c is not sensitive to the particular form of the viscous cutoff. This work represents a significant extension of the studies previously published in Schekochihin et al. 2004, PRL 92, 054502...

Schekochihin, A A; Brandenburg, A; Cowley, S C; Maron, J L; McWilliams, J C

2004-01-01

320

Inventory of future power and heat production technologies. Partial report Small-scale technology  

International Nuclear Information System (INIS)

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

2008-01-01

 
 
 
 
321

Evaluation of Small-Scale Laterally Loaded Non-Slender Monopiles in Sand  

DEFF Research Database (Denmark)

In current design of offshore wind turbines, monopiles are often used as foundation. The behaviour of the monopiles when subjected to lateral loading has not been fully investigated, e.g. the diameter effect on the soil response. In this paper the diameter effect on laterally loaded non-slender piles in sand is evaluated by means of results from six small-scale laboratory tests, numerical modelling of the same test setup and existing theory. From the numerical models p-y curves are conducted and compared to current design regulations. It is found that the recommendations in API (1993) and DNV (1992) are in poor agreement with the numerically obtained p-y curves. The initial stiffness, Epy*, of the p-y curves, is found to be dependent on the pile diameter, i.e. the initial stiffness increases with increasing pile diameter. Further, the dependency is found to be in agreement with the suggestions in Sørensen et al. (2010). It is found that considerable uncertainties are related to small-scale testing, and the different evaluations clearly indicate that the accuracy of small-scale testing is increased when increasing the pile diameter and applying overburden pressure.

Roesen, Hanne Ravn; Thomassen, Kristina

2010-01-01

322

Majorons: A simultaneous solution to the large and small scale dark matter problems  

International Nuclear Information System (INIS)

[en] It is shown that the existence of majorons, which enable a heavy neutrino, 500 eV 4 yr 8 yr can solve both the large and small scale dark matter problems. For a primordial 'Zeldovich' spectrum of fluctuations the limits are msub(?H) 107 to 108 Yr (the ranges msub(?H) or approx. 108 yr are allowed by the model but galaxy formation becomes problematic). The large scale dark matter problem is how to achieve the critical density as implied by inflation, the small scale problems deal with the halos of galaxies and galaxy formation and perturbation growth. The heavy neutrino could provide the solution to the small scale problem by initiating perturbation growth before decoupling. The decay products will be fast and thus not bound to the initial clumps, thus solving the large scale problem. The low mass relic neutrinos that were not decay products would remain bound in the gravitational potentials which grew from the initial perturbations. The resulting universe would be radiation dominated, which is consistent with present observations if H0 0 approx.= 50 km/s/Mpc. The majoron model parameters which best fit the dark matter considerations are presented. (orig.)

1984-10-18

323

High-temperature Elastic Structural Analysis on a Small-Scale PHE prototype  

International Nuclear Information System (INIS)

Hydrogen is considered a promising future energy solution because it is clean, abundant, and storable, and has high-energy density. One of the major challenges in establishing a hydrogen economy is how to produce massive quantities of hydrogen in a clean, safe, and economical way. Among the various hydrogen production methods, nuclear hydrogen production is garnering worldwide attention since it can produce hydrogen, a promising energy carrier, without an environmental burden. The PHE (Process Heat Exchanger) is a component that utilizes the nuclear heat from the nuclear reactor to provide hydrogen. A PHE is used in several processes such as nuclear steam reforming, nuclear methanol, nuclear steel, nuclear oil refinery, and nuclear steam. The PHE of the SO3 decomposer, which generates the process gas such as H2O, O2, SO2, and SO3 at a very high temperature, is a key component in the nuclear hydrogen program in Korea. Recently, KAERI (Korea Atomic Energy Research Institute) established a small-scale gas loop for the performance test of VHTR components and manufactured a small-scale PHE prototype made of Hastelloy-X. A performance test on the PHE prototype is under way in the small-scale gas loop at KAERI. In this study, in an effort to evaluate the high-temperature structural integrity of the PHE prototype under the test condition of the gas loop, a high-temperature elastic structural analysis was performed

2012-01-01

324

Will increase the use of small-scale biomass CPH; Vil oeke bruken av smaaskala biomasse CPH  

Energy Technology Data Exchange (ETDEWEB)

In KRAV (KRAft-Varme) project (Power-Heat) the main goal is to raise awareness within the small-scale biomass CHP systems (Combined Heat and Power) in order to assist the Norwegian industry and energy companies in this field and to develop an innovative concept for small-scale biomass CHP systems adapted Norwegian conditions. (AG)

Skreiberg, Oeyvind

2009-07-01

325

Guidelines for Management Consulting Programs for Small-Scale Enterprise. Appropriate Technologies for Development. Manual M-14.  

Science.gov (United States)

|This manual is designed to assist management consultants in working with small-scale entrepreneurs in developing countries. Addressed in an overview of the small-scale enterprise (SSE) are: the role of the SSE in third world development, problems of SSEs, and target firms. The second chapter deals with various forms of management assistance to…

Vaughan, Gary L.

326

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  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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-u...

Boerstler, Fritjof

327

Side Activities of Non-Farmers in Rural Areas in the Netherlands  

Directory of Open Access Journals (Sweden)

Full Text Available In many rural areas, not only in The Netherlands but also elsewhere in Europe, has been observed a variety of employment opportunities for rural populations, following the decline in traditional agricultural employment. This contributes to the fact that the countryside is changing and rural areas can be viewed as new spaces of work. As a result, rural economy is no longer dominated by agricultural activities, but by activities such as small scale industrial production, service provision, landscape management, and residential use. To a certain extent these activities have the form of side-activities next to primary income sources. Most attention in both scientific literature and policies is focused on side-activities by farmers, such as agro-tourism and direct marketing. However, according to empirical data from The Netherlands, most side-activities are developed by non-farmers. In this paper the focus is on this last group. The amounts and types of non-farmers’ and farmers side-activities will be deployed, together with their motives to start new entrepreneurship endeavors and the impact on the local community. It will be argued that this type of activities will stimulate rural economic development offering new job opportunities for income generation to the rural inhabitants and create new economic spaces in rural geographical contexts transforming the rural economy.

Marianna Markantoni; Dirk Strijker

2012-01-01

328

An Evaluation of Farmers’ Participation in Afforestation Programme in Kogi State, Nigeria  

Directory of Open Access Journals (Sweden)

Full Text Available Extensive deforestation has reduced the 65 million hectares of intact forest cover of 1897 in Nigeria to thepresent 4 million hectares. The consequences of this unhealthy development have resulted to environmentaldegradation and accelerated wind and water erosion of the fertile land that has also left Nigerian soil too poor forsustainable agricultural production. Reforestation through small-scale village based farmers’ participation nowform one of the strategies embarked upon by several agencies in Nigeria including Kogi afforestation project.This study attempts to evaluate farmers’ participation in afforestation project in Kogi State. Structuredquestionnaire was used to interview 120 participants. Descriptive statistics, adoption index and sigma methodwere used to describe socio-economic characteristics, participation methods and to measure the level of adoptionwhile chi-square was used to find differences between income generated from adoption of the variousafforestation technologies. Findings reveal that 67 percent of the farmers had little or no formal education, morethan 30 percent of the farmers underwent passive participation in afforestation while adoption of improvedseedlings, exotic trees and pure stand technologies received high score of 4.90, 4.74 and 4.44 respectively. Seedscarification and harvesting by chipping technologies received the least adoption score of 2.61 and 2.94. Thechi-square test adjudged that there was a significant difference between income generated and type of technologyadopted. This study recommends that more pragmatic interactive participation method that will give room forjoint analysis of action plan and formation of local institutions should be put in place.

O.J. Saliu; J.S Alao; T Oluwagbemi

2010-01-01

329

Assessing the Contribution of Small Scale Water Resources Development Project on Agricultural and Social Advancement in Bangladesh: a Case Study for Haizda Embankment Project  

Directory of Open Access Journals (Sweden)

Full Text Available An investigation was made on the Haizda Embankment project in the Haor area of Netrokona district to evaluate the goals and objectives of the project. Data collected from 50 farmers, 20 project staff, local government officials and expert through a structured questionnaire. Both pre-project and post-project situations were taken into consideration. The agricultural and social development were appraised on land use, use of seed variety, fertilizer use, water management, labour employment, yearly income of the farmers, land ownership, use of insecticides, transportation facility and educational changes. The pre-project and post-project scenario in the above mentioned aspects were statistically compared by means of t-test. Significant improvements in almost all the aspects were found at the post-project condition. On the other hand analyzing highest water levels of the area, it was found that the water level significantly increased outside the embankment after the project construction, which also increased the vulnerability of livelihood. At the same time fish production in Mohanganj Thana significantly decreased after the embankment construction and also decreasing rate is continuing. The fisheries ecology have been changed in the poldered area because of (i) free entrance of water is prevented at low flood level, (ii) the requirement and spawning ground of major fish species have been interrupted and (iii) decreased the opportunity of capture fishing in the project area. So, planners should consider the related adverse effects on nature and environment and its remedial measures during the planning of this type of small-scale water resources development project.

Md. Mujibur Rahman; M. N. Islam; M. A. Taher

2002-01-01

330

Coronal hole boundaries at small scales: IV. SOT view Magnetic field properties of small-scale transient brightenings in coronal holes  

CERN Document Server

We study the magnetic properties of small-scale transients in coronal hole. We found all brightening events are associated with bipolar regions and caused by magnetic flux emergence followed by cancellation with the pre-existing and newly emerging magnetic flux. In the coronal hole, 19 of 22 events have a single stable polarity which does not change its position in time. In eleven cases this is the dominant polarity. The dominant flux of the coronal hole form the largest concentration of magnetic flux in terms of size while the opposite polarity is distributed in small concentrations. In the coronal hole the number of magnetic elements of the dominant polarity is four times higher than the non-dominant one. The supergranulation configuration appears to preserve its general shape during approximately nine hours of observations although the large concentrations in the network did evolve and were slightly displaced, and their strength either increased or decreased. The emission fluctuations seen in the X-ray bri...

Huang, Z; Doyle, J G; Lamb, D A

2012-01-01

331

Impact of small-scale distribution of basal pressure for subglacial hydrology  

Science.gov (United States)

With the ongoing development of 2D subglacial hydrological models, new challenges to simulate the geometry of the drainage system arise notably as their resolution becomes finer. Indeed, the influence of small-scale ice mechanics and small-scale bed topography on subglacial water and ice flow is more likely to take over large-scale forcing. At the Svartisen Subglacial Laboratory (SSL - 200 m below the ice surface), we investigate the importance of basal normal pressure on constraining water flow path over different time scale and hypothesise its importance for water transfer from a channelized drainage system to a distributed one. Twenty years of field observations of normal basal pressure reveal short-lived pressure events, which are assumed to be related to the seasonal development of the hydrological system. We analyse their frequency and amplitude in relation to subglacial runoff measured close to a subglacial tunnel intake located 600-500m above the glacier snout. These events are characterised by a drop in pressure of as much as 1 MPa in a matter of several hours and a sudden rise reaching more than twice the overburden pressure. The cause of this phenomenon seems to be the melting/migration of subglacial channels. Their occurrence is linked to periods of melt and rainfall, when the high capacity drainage system is pressurized above the ice overburden pressure. Then, as water pressure becomes lower than the ice flotation level, the centre part of channels is decoupled from the glacier bed. This decrease in contact area between the ice and the bed produces stresses greater than the mean ice overburden pressure around the channel sides. As a consequence, the flooded area surrounding the high capacity drainage system is sealed off by this large increase in pressure, creating local storage as mentioned in other studies. This water retention can be a highly significant feedback for ice dynamics creating large areas of high pressure that can be reactivated during speed-up events or a surge. In this study, we provide a long-term analysis of the occurrence of those events and infer their significance for maintaining areas of high water pressure over different time-scales (days, months and years) as well as for the basal drag. Finally, we discuss the importance of small-scale observations in the light of measurements showing very strong spatial disparities in normal pressure for two pairs of sensors located less than a meter apart. Discharge measurements provide further insights into the overall behaviour of the subglacial system. Strong correlation with subglacial normal pressure demonstrates the existence of rare global events. In contrast, locally independent events are more frequent suggesting very variable water flow paths and a more distributed drainage system. These last observations suggest periods of water flow controlled mainly by small-scale pressure distribution and small-scale topography. These results highlight the importance of the transition between high and low pressurised drainage system regarding local water storage and its possible impact on ice dynamics. As the resolution of models increases, new small-scale processes will have to be included.

Lefeuvre, Pierre-Marie; Jackson, Miriam; Lappegard, Gaute; Ove Hagen, Jon

2013-04-01

332

Analysis of environmental issues related to small-scale hydroelectric development. III. Water level fluctuation  

Energy Technology Data Exchange (ETDEWEB)

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.

Hildebrand, S.G. (ed.)

1980-10-01

333

Small-scale auroral structures observed simultaneously at the top and bottom of the ionosphere  

International Nuclear Information System (INIS)

Complete text of publication follows. The Auroral Current and Electrodynamics Structure (ACES) sounding rocket mission was launched from the Poker Flat Research Range on January 29, 2009 into a stable auroral arc just north of Fort Yukon, Alaska. Its objective is to help refine current models of auroral structures. The mission consists of two nearly identical payloads mounted on Black Brant V and IX rockets, respectively. The two payloads, a high flyer and a low flyer reaching about 365 km and 130 km altitude, respectively, were launched one minute apart in order to be magnetically conjugate at apogee (i.e., sample the same magnetic field line). The payloads were instrumented to measure DC and AC electric and magnetic fields, HF radio waves, suprathermal and energetic ion and electron fluxes, plasma density, and optical auroral emissions. The Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E) contributed to the mission with two magnetic field sensors (Rogowsky coils) designed to measure directly the current density integrated over the (circular) cross section of the coils. No further assumptions about the current structure are necessary except that they are uniform across the plane of the coils which measures slightly less than 100 cm2. The coils' principal frequency range covers the 1-400 Hz band which makes them ideal to sample accurately small-scale field-aligned currents in the ionosphere. In our presentation we will show first results from an analysis of our measurements of small-scale auroral electric currents. We will further put the results in context to present knowledge of small-scale structures in the aurora and their role in coupling the high-latitude ionosphere to the magnetosphere.

2009-01-01

334

Effect of Illegal Small-Scale Mining Operations on Vegetation Cover of Arid Northern Ghana  

Directory of Open Access Journals (Sweden)

Full Text Available Illegal small-scale gold mining brings several benefits to developing countries like Ghana, manifested mainly as employment and revenue but simultaneously impacts negatively on the immediate environment. The study tested the hypothesis that density and diversity of key native tree and shrub species differ in the mined and unmined areas of Nangodi in the Talensi-Nabdam District of the Upper East Region, Ghana. A total of 20 plots (10×10 m) were studied in the mined and unmined areas. A total of 8 tree species and 9 shrub species were recorded. The extent of vegetation affected by the activities of illegal small scale miners was assessed. The Simpsons reciprocal diversity index of tree species at mined area was 8.33 as compared to 10.8 for the unmined area. For shrub species, the Simpsons reciprocal diversity index was 8.33 for the mined areas while that of the unmined was 10.2. Common trees and shrubs species were identified in both areas as designated by the calculated Jaccards similarity index of 0.6 for trees and 0.7 for shrubs. However low mean density of 2.4 individual trees per 100 m2 and 5.6 individuals per 100 m2 was recorded in the mined and unmined areas respectively. Shrubs species also recorded very low density figures of 1.4 and 2.6 per 100 m2 in the mined and unmined areas, respectively. The null hypothesis that there is no significant difference of illegal small-scale mining on tree and shrub species density is rejected at the 0.05 significant level, indicating that mining significantly affected vegetation cover. It is suggested that efforts should be made to reclaim the degraded lands through reforestation.

D. Tom-Dery; Z. J. Dagben; S.J. Cobbina

2012-01-01

335

A small scale cell culture system to analyze mechanobiology using reporter gene constructs and polyurethane dishes  

DEFF Research Database (Denmark)

Mechanical forces are translated into biochemical signals and contribute to cell differentiation and phenotype maintenance. Mesenchymal stem cells and their tissue-specific offspring, as osteoblasts and chondrocytes, cells of cardiovascular tissues and lung cells are sensitive to mechanical loading but molecules and mechanisms involved have to be unraveled. It is well established that cellular mechanotransduction is mediated e.g. by activation of the transcription factor SP1 and by kinase signaling cascades resulting in the activation of the AP1 complex. To investigate cellular mechanisms involved in mechanotransduction and to analyze substances, which modulate cellular mechanosensitivity reporter gene constructs, which can be transfected into cells of interest might be helpful. Suitable small-scale bioreactor systems and mechanosensitive reporter gene constructs are lacking. To analyze the molecular mechanisms of mechanotransduction and its crosstalk with biochemically induced signal transduction, AP1 and SP1 luciferase reporter gene constructs were cloned and transfected into various cell lines and primary cells. A newly developed bioreactor and small-scale 24-well polyurethane dishes were used to apply cyclic stretching to the transfected cells. 1 Hz cyclic stretching for 30 min in this system resulted in a significant stimulation of AP1 and SP1 mediated luciferase activity compared to unstimulated cells. In summary we describe a small-scale cell culture/bioreactor system capable of analyzing subcellular crosstalk mechanisms in mechanotransduction, mechanosensitivity of primary cells and of screening the activity of putative mechanosensitizers as new targets, e.g. for the treatment of bone loss caused by both disuse and signal transduction related alterations of mechanotransduction.

Seefried, Lothar; Mueller-Deubert, Sigrid

2010-01-01

336

A small scale cell culture system to analyze mechanobiology using reporter gene constructs and polyurethane dishes  

Directory of Open Access Journals (Sweden)

Full Text Available Mechanical forces are translated into biochemical signals and contribute to cell differentiation and phenotype maintenance. Mesenchymal stem cells and their tissue-specific offspring, as osteoblasts and chondrocytes, cells of cardiovascular tissues and lung cells are sensitive to mechanical loading but molecules and mechanisms involved have to be unraveled. It is well established that cellular mechanotransduction is mediated e.g. by activation of the transcription factor SP1 and by kinase signaling cascades resulting in the activation of the AP1 complex. To investigate cellular mechanisms involved in mechanotransduction and to analyze substances, which modulate cellular mechanosensitivity reporter gene constructs, which can be transfected into cells of interest might be helpful. Suitable small-scale bioreactor systems and mechanosensitive reporter gene constructs are lacking. To analyze the molecular mechanisms of mechanotransduction and its crosstalk with biochemically induced signal transduction, AP1 and SP1 luciferase reporter gene constructs were cloned and transfected into various cell lines and primary cells. A newly developed bioreactor and small-scale 24-well polyurethane dishes were used to apply cyclic stretching to the transfected cells. 1 Hz cyclic stretching for 30 min in this system resulted in a significant stimulation of AP1 and SP1 mediated luciferase activity compared to unstimulated cells. In summary we describe a small-scale cell culture/bioreactor system capable of analyzing subcellular crosstalk mechanisms in mechanotransduction, mechanosensitivity of primary cells and of screening the activity of putative mechanosensitizers as new targets, e.g. for the treatment of bone loss caused by both disuse and signal transduction related alterations of mechanotransduction.

L Seefried; S Mueller-Deubert; T Schwarz; T Lind; B Mentrup; M Kober; D Docheva; A Liedert; M Kassem; A Ignatius; M Schieker; L Claes; W Wilke; F Jakob; R Ebert

2010-01-01

337

THE SUN'S SMALL-SCALE MAGNETIC ELEMENTS IN SOLAR CYCLE 23  

International Nuclear Information System (INIS)

With the unique database from the Michelson Doppler Imager on board the Solar and Heliospheric Observatory in an interval embodying solar cycle 23, the cyclic behavior of solar small-scale magnetic elements is studied. More than 13 million small-scale magnetic elements are selected, and the following results are found. (1) The quiet regions dominated the Sun's magnetic flux for about 8 years in the 12.25 year duration of cycle 23. They contributed (0.94-1.44) x1023 Mx flux to the Sun from the solar minimum to maximum. The monthly average magnetic flux of the quiet regions is 1.12 times that of the active regions in the cycle. (2) The ratio of quiet region flux to that of the total Sun equally characterizes the course of a solar cycle. The 6 month running average flux ratio of the quiet regions was larger than 90.0% for 28 continuous months from July 2007 to October 2009, which very well characterizes the grand solar minima of cycles 23-24. (3) From the small to the large end of the flux spectrum, the variations of numbers and total flux of the network elements show no correlation, anti-correlation, and correlation with sunspots, respectively. The anti-correlated elements, covering the flux of (2.9-32.0)x1018 Mx, occupy 77.2% of the total element number and 37.4% of the quiet-Sun flux. These results provide insight into the reason for anti-correlations of small-scale magnetic activity during the solar cycle.

2011-04-10

338

Small-Scale Testing of Laterally Loaded Non-Slender Piles in a Pressure Tank  

DEFF Research Database (Denmark)

The monopile foundation concept is often employed as the foundation for offshore wind turbines. Typically, piles with diameters of 4-6 m and embedded lengths of 15-30 m are employed. Hence, the length to diameter ratio is around 5. The design method recommended by the American Petroleum Institute and Det Norske Veritas is, however, based on slender piles with length to diameter ratios larger than 10. Hence, the design method needs to be validated for non-slender piles. The aim of the present work is to investigate the pile behaviour for non-slender piles by means of small-scale testing. When conducting small-scale tests the low effective stresses in the soil is one of the major un-certainties. At low stresses the soil parameters will vary greatly with depth and the determination of soil parameters is therefore subject to uncertainties. This problem can be overcome by in¬creasing the effective stresses in the soil. A new and innovative test setup for small-scale tests is presented. Tests were successfully carried out in a pressure tank enabling the possibility of ho¬mogeneously increasing the effective stresses. The test setup is described in detail in the paper. A total of 29 quasi-static tests were conducted on six piles with diameters between 40 and 100 mm and length to diameter ratios of 3-6 m. The effect of applying an overburden pressure is eval¬uated for the load-displacement relationships and the variation of pile deflection with depth.

SØrensen, SØren Peder Hyldal; Ibsen, Lars Bo

2012-01-01

339

Extensional basin evolution in the presence of small-scale convection : Subsidence and stratigraphy  

DEFF Research Database (Denmark)

The plate model of Parsons & Sclater provides a generally accepted, quantitative framework for the thermal subsidence-evolution in extensional basins. It predicts an asymptotic evolution of the geotherm towards a steady state, featuring a constant lithospheric thickness and ceased subsidence. This is formulated by assuming that the temperature at a fixed depth (the asymptotic thickness of the lithosphere) is constant. It is implicitly assumed, that this temperature is maintained by sub-lithospheric, small-scale convection, but the dynamics, controlling this process, are not considered. Here, we apply a two-dimensional, numerical, thermo-mechanical model of the lithosphere and upper mantle to asses the effects of small-scale convection. Given a particular mantle rheology, our model features such convection, and, over time, the horizontally averaged geotherm converges towards a self-consistent, quasi-steady-state. Extension of the convecting equilibrium model causes the formation of rifts or continental margins which, posterior to extension, cools and subsides as predicted by the plate model. However, in contrast to the plate model, the ascended asthenosphere is not instantaneously decoupled from the convecting upper mantle below, and cooling is thus not entirely conductive above the former base of the lithosphere. This causes significantly protracted cooling and subsidence.We show that our model features improved consistency with subsidence data from several rifted margins and intracontinental basins. Furthermore, our model shows that the long-term subsidence pattern in the presence of small-scale convection is superimposed by vertical movements at periods of 2-20 Myr due to convection dynamics at the base of the lithosphere. We show that these movements are a recurrent and potential cause for the development of stratigraphic sequences at similar time scale. Since such sequences are commonly assumed to be caused by eustatic variations, our results have important implications forinferences on the latter. Our results are furthermore important for the assessment of hydrocarbon potential of sedimentary basins in terms of stratigraphic correlation and thermal maturation.

Petersen, Kenni Dinesen; Nielsen, S.B.

340

Statistical maps of small-scale electric field variability in the high-latitude ionosphere  

Science.gov (United States)

Statistical maps of small-scale electric field variability in the high-latitude ionosphere are derived for the Northern and Southern Hemispheres using 48 months of data from the Super Dual Auroral Radar Network (SuperDARN). Maps of variability magnitude (from scales of 45-450 km and 2-20 min) are derived for a range of interplanetary magnetic field (IMF) orientations and dipole tilt angles (the angle between the best fit dipole axis and the plane perpendicular to the Sun-Earth line). It is found that the observed spatial distribution of average variability is significantly modified as the IMF and dipole tilt conditions change. Under negative (winter-like) and neutral (equinox-like) dipole tilt angles, variability is concentrated in the auroral and dayside cusp regions, and the spatial distributions of variability appear to be correlated to those of large- and small-scale field-aligned currents (FACs). Additionally, variability on the nightside is found to be more enhanced in the downward FAC region than it is in the upward FAC region. Under positive (summer-like) dipole tilt angles, the average variability magnitudes across the high-latitude regions are smaller than those observed under negative dipole tilt angles, and the spatial distributions are more uniform. These dipole tilt effects suggest that scale-size- and conductivity-dependent field-aligned potential drops and conductivity-dependent changes in the processes that generate variability are possible factors that impact the observed small-scale electric field variability. In general, Southern Hemisphere maps appear very similar to Northern Hemisphere maps, although some minor differences are observed that may result from interhemispheric asymmetries in the geomagnetic field.

Cousins, E. D. P.; Shepherd, S. G.

2012-12-01

 
 
 
 
341

Evaluation of the Accountings Systems Used by Small Scale Enterprises in Nigeria: The Case of Enugu- South East Nigeria  

Directory of Open Access Journals (Sweden)

Full Text Available The study evaluated the accounting systems in use by small scale enterprises operating in Enugu, South East of Nigeria. The study was necessitated due to high rate of small scale enterprises failure. The population of the study consists of 242 accounting officers and proprietors of small scale enterprises operating in Enugu. 148 respondents were selected through a simple random sampling technique. The instrument employed for the study was a structured questionnaire. Four research questions and one null hypothesis tested at 0.05 level of significance guided the study. Data were analyzed using mean and standard deviation and t-test. Summary of the results revealed that seven accounting systems were available for use to small scale enterprises operating in Enugu, significant number of small scale enterprises use the single entry system of accounting and that keeping of proper accounting records enhances profitability. It was concluded that significant number of small scale enterprises in Enugu use the single entry accounting system because of its simplicity and that there was correlation between proper record keeping and profitability of small scale enterprises. It was recommended among other things that the Ministry of Commerce and Industry should help the small business owners to avail themselves the opportunity to use the accounting systems that are relevant for the day to day reporting of their business transactions.

B.E. Okoli

2011-01-01

342

A partnership approach for Electronic Data Capture in small-scale clinical trials.  

UK PubMed Central (United Kingdom)

Amid researchers' growing need for study data management, the CTSA-funded Institute for Translational Health Sciences developed an approach to combine technical and scientific resources with small-scale clinical trials researchers in order to make Electronic Data Capture more efficient. In a 2-year qualitative evaluation we found that the importance of ease of use and training materials outweighed number of features and functionality. EDC systems we evaluated were Catalyst Web Tools, OpenClinica and REDCap. We also found that two other systems, Caisis and LabKey, did not meet the specific user needs of the study group.

Franklin JD; Guidry A; Brinkley JF

2011-12-01

343

A partnership approach for Electronic Data Capture in small-scale clinical trials.  

Science.gov (United States)

Amid researchers' growing need for study data management, the CTSA-funded Institute for Translational Health Sciences developed an approach to combine technical and scientific resources with small-scale clinical trials researchers in order to make Electronic Data Capture more efficient. In a 2-year qualitative evaluation we found that the importance of ease of use and training materials outweighed number of features and functionality. EDC systems we evaluated were Catalyst Web Tools, OpenClinica and REDCap. We also found that two other systems, Caisis and LabKey, did not meet the specific user needs of the study group. PMID:21651992

Franklin, Joshua D; Guidry, Alicia; Brinkley, James F

2011-05-30

344

Poverty Measurements in Small-scale Fisheries of Ghana: A Step towards Poverty Eradication  

Directory of Open Access Journals (Sweden)

Full Text Available This study examined measurements of poverty in small-scale fishing communities of Ghana using FGT techniques and the Sumaila Relative Poverty Indices. Findings show that poverty head-count index was between 35.5% and 50% using the Local Poverty line and up to 80% using the International Poverty line. In terms of vulnerability, irrespective of the main fishing activity, community (rural or urban) and habitat of fishery resources (freshwater or marine), fishers were facing identical sources of vulnerability. Marginalization indicators were relatively better in the urban fishing communities (90%) than in the rural fishing communities (50%-80%).

Berchie Asiedu; Francis K.E. Nunoo; Patrick K. Ofori-Danson; Daniel B. Sarpong; Ussif R. Sumaila

2013-01-01

345

Photospheric network bright points and the problem of the small-scale solar magnetic field organization  

International Nuclear Information System (INIS)

[en] Facular points are considered as a kind of a structure linking photospheric to subphotospheric layers. The Network Bright Points (NBPs) position is identified on two high resolution photographs taken from long time series obtained in the Pic du Midi Observatory. NBPs relative coordinates have been obtained on a coordinate measuring device at the Rozhen National Astronomical Observatory. The results from the statistically processed data show that the NBPs surface distribution is not random. It is assumed that the NBPs indicate a small-scale Kg magnetic field. A hypothesis based on the obtained results is proposed on the problem of solar magnetic field generation. 2 figs., 6 refs

1990-01-01

346

Technology transfer of small-scale energy technologies in the US Pacific Territories  

Energy Technology Data Exchange (ETDEWEB)

From 1977 to 1981 the Department of Energy has awarded 32 grants for small-scale energy projects in the US Pacific Territories. A critical issue with these projects has been transferring the technology within the community once the project has been completed. Certain projects are more successful at this than others. There are elements common to projects which are the most successful in this regard. In addition, there appear to be five different types of technology transfer processes. This paper identifies these processes, illustrates each with a case study, and points out the common elements. Perhaps this information can be used when designing other projects to facilitate technology transfer in developing countries.

Case, C.W.

1982-01-01

347

Satellite measurements reveal persistent small-scale features in ocean winds.  

UK PubMed Central (United Kingdom)

Four-year averages of 25-kilometer-resolution measurements of near-surface wind speed and direction over the global ocean from the QuikSCAT satellite radar scatterometer reveal the existence of surprisingly persistent small-scale features in the dynamically and thermodynamically important curl and divergence of the wind stress. Air-sea interaction over sea surface temperature fronts throughout the world ocean is evident in both the curl and divergence fields, as are the influences of islands and coastal mountains. Ocean currents such as the Gulf Stream generate distinctive patterns in the curl field. These previously unresolved features have important implications for oceanographic and air-sea interaction research.

Chelton DB; Schlax MG; Freilich MH; Milliff RF

2004-02-01

348

(A small-scale study of Rocky Flats uncalcined incinerator ash dissolution and filtrate anion exchange)  

Energy Technology Data Exchange (ETDEWEB)

Small scale experimentation was conducted with incinerator ash in the nitric/hydrofluoric acid cascade dissolver and the anion exchange systems at Rocky Flats and Los Alamos National Laboratories for the purpose of determining the following: to determine the relationship between calcium fluoride dissolution feed levels and plutonium dissolution yields. To determine the relationship between calcium fluoride feed levels to dissolution, and the performance of anion exchange when processing dissolution filtrate. To determine the effect of carbonaceous materials on the dissolution and anion exchange when recovering plutonium from incinerator ash.

1990-01-01

349

Small scale anisotropies of UHECRs from super-heavy halo dark matter  

Energy Technology Data Exchange (ETDEWEB)

The decay of very heavy metastable relics of the Early Universe can produce ultra-high energy cosmic rays (UHECRs) in the halo of our own Galaxy. In this model, no Greisen-Zatsepin-Kuzmin cutoff is expected because of the short propagation distances. They show here that, as a consequence of the hierarchical build up of the halo, this scenario predicts the existence of small scale anisotropies in the arrival directions of UHECRs, in addition to a large scale anisotropy, known from previous studies. They also suggest some other observable consequences of this scenario which will be testable with upcoming experiments, as Auguer, EUSO and OWL.

P. Blasi; R. K. Sheth

2001-10-23

350

Gravitational collapse of small-scale structure as the origin of the Lyman alpha forest  

CERN Multimedia

If gravitational clustering is a hierarchical process, the present large-scale structure of the galaxy distribution implies that structures on smaller scales must have formed at high redshift. We simulate the formation of small-scale structure (average cell mass: \\Delta \\bar m_b=10^{4.2}M_\\odot) and the evolution of photoionized gas, in the specific case of a CDM model with a cosmological constant. The photoionized gas has a natural minimal scale of collapse, the Jeans scale (m_{b,J}\\simeq 10^{9}M_\\odot). We find that low column density (\

Cen, R; Ostriker, J P; Miralda-Escude, Jordi; Ostriker, Jeremiah P

1994-01-01

351

A T-matrix approach for particles with small-scale surface roughness  

Directory of Open Access Journals (Sweden)

Full Text Available We combine group theory with a perturbation approach to perform T-matrix computations for particles with small-scale surface roughness up to size parameters of 70. The optical properties of high-order 3D-Chebyshev particles differ substantially from those of spheres. CPU times are reduced by more than 4-5 orders of magnitude by the use of group theory, while the perturbation approach circumvents the notorious ill-conditioning problems of the null-field method, thus allowing the treatment of large size parameters.

M. Kahnert; T. Rother

2011-01-01

352

Basic study natural gas small-scale consumption 1991 in the Netherlands  

International Nuclear Information System (INIS)

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 m3 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.

1991-01-01

353

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

Energy Technology Data Exchange (ETDEWEB)

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)

None

1980-02-01

354

Small-Scale Cyclic Tests on Nonslender Piles Situated in Sand : test results  

DEFF Research Database (Denmark)

In the period from August 2011 till October 2011 a series of small-scale tests on pile foundations has been conducted at Aalborg University. In all the tests, the piles have been exposed to cyclic loading consisting of 20-25 load cycles and all the tests have been conducted in a pressure tank. The objective of the tests has been to investigate the effect of pile diameter, length to diameter ratio and cyclic loading on the soil response for non-slender piles in sand.

SØrensen, SØren Peder Hyldal; Ibsen, Lars Bo

2011-01-01

355

Small-Scale Fluctuations in Cosmic X-ray Background A Power Spectrum Approach  

CERN Multimedia

Equations to investigate fluctuations in cosmic X-ray background radiation due to point-like sources at high-redshift are formulated in a systematic way. The angular power spectrum of X-ray background fluctuations is investigated from large-scales to small-scales in various cosmological models such as open universe models and models with the cosmological constant, assuming a simple evolution model of the sources. The effect of epoch-dependent bias is demonstrated for small-angle fluctuations. The contribution from shot noise fluctuations is also discussed.

Yamamoto, K; Yamamoto, Kazuhiro; Sugiyama, Naoshi

1998-01-01

356

Background information to the installers guide for small scale mains connected PV  

Energy Technology Data Exchange (ETDEWEB)

This report contains background information used by BRE, EA Technology, Halcrows and Sundog when compiling guidance for the UK's New and Renewable Energy Programme on the installation of small-scale photovoltaics (PV) in buildings. The report considers: relevant standards; general safety issues; fire and safety issues, including the fire resistance of PV modules; PV module ratings such as maximum voltage and maximum current; DC cabling; the DC disconnect; the DC junction box; fault analysis; general and AC side earthing; DC earthing; lightning and surge suppression; inverters; AC modules; AC systems; getting connection; mounting options; and installation issues.

NONE

2002-07-01

357

Design and experimental investigations on a small scale traveling wave thermoacoustic engine  

Science.gov (United States)

A small scale traveling wave or Stirling thermoacoustic engine with a resonator of only 1 m length was designed, constructed and tested by using nitrogen as working gas. The small heat engine achieved a steady working frequency of 45 Hz. The pressure ratio reached 1.189, with an average charge pressure of 0.53 MPa and a heating power of 1.14 kW. The temperature and the pressure characteristics during the onset and damping processes were also observed and discussed. The experimental results demonstrated that the small engine possessed the potential to drive a Stirling-type pulse tube cryocooler.

Chen, M.; Ju, Y. L.

2013-02-01

358

Department of Energy Small-Scale Hydropower Program: Feasibility assessment and technology development summary report  

International Nuclear Information System (INIS)

This report summarizes two subprograms under the US Department of Energy's Small-Scale Hydroelectric Power Program. These subprograms were part of the financial assistance activities and included the Program Research and Development Announcement (PRDA) feasibility assessments and the technology development projects. The other major subprograms included engineering research and development, legal and institutional aspects, and technology transfer. These other subprograms are covered in their respective summary reports. The problems of energy availability and increasing costs of energy led to a national effort to develop economical and environmental attractive alternative energy resources. One such alternative involved the utilization of existing dams with hydraulic heads of

1991-01-01

359

Effect of small-scale density perturbations on the formation of dark matter halo profiles  

Science.gov (United States)

With the help of a set of toy N-body models of dark halo formation, we study the impact of small-scale initial perturbations on the inner density profiles of haloes. We find a significant flattening of the inner slope ? to ?=-0.5 in some range of scales and amplitudes of the perturbations (while in the case of absence of these perturbations, the Navarro-Frenk-White profile with ?=-1 is reproduced). This effect may be responsible for the formation of cuspless galactic haloes.

Pilipenko, S. V.; Doroshkevich, A. G.; Lukash, V. N.; Mikheeva, E. V.

2012-11-01

360

Small-scale and large-scale creep predictions of notch stress and strain under creep conditions  

International Nuclear Information System (INIS)

Simple expressions are proposed for predicting the notch stress and strain, by applying the concept of the state of small-scale and large-scale creep conditions with the path-independence of the J-integral. A simple equation is obtained, which predicts a stress concentration factor varying with time under the small-scale creep conditions from the elastic stress concentration factor K*t. An ordinary differential equation is derived for estimating the stress concentration factor under the small-scale to large-scale creep conditions. Expressions for a strain concentration factor are also proposed. The applicability of the proposed predictions is demonstrated using finite element calculations. (orig.).

1991-01-01

 
 
 
 
361

Cocoa Farmer Field School Graduate Farmers Perceived Benefits of FFS Training in Ondo State, Nigeria  

Directory of Open Access Journals (Sweden)

Full Text Available The study assessed the perceived benefits of Farmer Field School graduate farmers as a result of their participation in FFS training. The specific objectives were to: describe the socio-economic characteristics of the respondents, identify major cocoa farmers’ perceived benefit items; determine the level of benefit; compare cocoa FFS farmers performance in terms of benefits/costs with non-FFS cocoa farmers. A multi-stage sampling procedure was used in composing 77 FFS graduate farmers and 76 non-FFS farmers for the study. Data were analysed using various descriptive statistics (frequency counts, percentages, means and standard deviation) and inferential statistics (t-test). The findings of the study indicated that the FFS farmers benefited in terms if improved income, increased yield, reduction of farm costs and other aspects. The t-tests result comparing the FFS Farmers with non-FFS farmers on some benefits/cost items showed that the FFS farmers were better off. It was therefore concluded that FFS training was beneficial to the cocoa farmers and recommended that FFS be extended to other categories of farmers to promote its beneficial effects.

S.O. Ebewore

2013-01-01

362

Small scale aspects of warm dark matter : power spectra and acoustic oscillations  

CERN Multimedia

We provide a semi-analytic study of the small scale aspects of the power spectra of warm dark matter (WDM) candidates that decoupled while relativistic with arbitrary distribution functions. These are characterized by two widely different scales $k_{eq} \\sim 0.01\\,(\\mathrm{Mpc})^{-1}$ and $k_{fs}= \\sqrt{3}\\,k_{eq}/2\\,\\langle V^2_{eq} \\rangle^\\frac{1}{2} $ with $\\langle V^2_{eq} \\rangle^\\frac{1}{2} \\ll 1 $ the velocity dispersion at matter radiation equality. Density perturbations evolve through three stages: radiation domination when the particle is relativistic and non-relativistic and matter domination. An early ISW effect during the first stage leads to an enhancement of density perturbations and a plateau in the transfer function for $k \\lesssim k_{fs}$. An effective fluid description emerges at small scales which includes the effects of free streaming in initial conditions and inhomogeneities. The transfer function features \\emph{WDM-acoustic oscillations} at scales $k \\gtrsim 2 \\,k_{fs}$. We study the p...

Boyanovsky, Daniel

2010-01-01

363

Seeking Observable Imprints of Small-Scale Structure on the Properties of Dark Matter Haloes  

CERN Multimedia

The characteristic prediction of the Cold Dark Matter (CDM) model of cosmological structure formation is that the Universe should contain a wealth of small-scale structure -- low-mass dark matter haloes and subhaloes. However, galaxy formation is inefficient in their shallow potential wells and so we expect these low-mass haloes and subhaloes to be dark. Can we tell the difference between a Universe in which low-mass haloes are present but dark and one in which they never formed, thereby providing a robust test of the CDM model? We address this question using cosmological simulations to examine how properties of low-mass haloes that are potentially accessible to observation, such as their spatial clustering, rate of accretions and mergers onto massive galaxies and the angular momentum content of massive galaxies, differ between a LCDM model and dark matter models in which low-mass halo formation is suppressed. Adopting an effective cut-off mass scale M_cut below which small-scale power is suppressed in the in...

Power, Chris

2013-01-01

364

Digging, damming or diverting? Small-scale irrigation in the Blue Nile basin, Ethiopia  

Directory of Open Access Journals (Sweden)

Full Text Available The diversity of small-scale irrigation in the Ethiopian Blue Nile basin comprises small dams, wells, ponds and river diversion. The diversity of irrigation infrastructure is partly a consequence of the topographic heterogeneity of the Fogera plains. Despite similar social-political conditions and the same administrative framework, irrigation facilities are built, used and managed differently, ranging from informal arrangements of households and 'water fathers' to water user associations, as well as from open access to scheduled irrigation. Fogera belongs to Ethiopian landscapes that will soon transform as a consequence of large dams and huge irrigation schemes. Property rights to land and water are negotiated among a variety of old and new actors. This study, based on ethnographic, hydrological and survey data, synthesises four case studies to analyse the current state of small-scale irrigation. It argues that all water storage options have not only certain comparative advantages but also social constraints, and supports a policy of extending water storage 'systems' that combine and build on complementarities of different storage types instead of fully replacing diversity by large dams.

Irit Eguavoen; Sisay Demeku Derib; Tilaye Teklewold Deneke; Matthew McCartney; Ben Adol Otto; Saeed Seidu Billa

2012-01-01

365

Small Scale Supplier Satisfaction: An Explorative Finding from Indian Manufacturing Industry  

Directory of Open Access Journals (Sweden)

Full Text Available Long term relationship only exists if the stake holders of the relationship share an output call satisfaction. In industrial buyer supplier relationship it is mandatory that buying organization or buyer should ensure selling organization's or seller's satisfaction within the boundaries of the strategic walls. In an integrated supplier relationship management (SRM) cycle supplier satisfaction plays a vital role for the continual and smooth running of the cycle. The changing trend of purchasing and dramatically changing supply chain relationships forcing the buyers to concentrate and ensure the supplier satisfaction. The role of small scale suppliers is substantial in providing the competitive edge to the manufacturing organizations. So it is advisable to keep the satisfaction level of the SSI suppliers high in order to meet the desired operational flexibility. The satisfaction level of small scale suppliers only can be improved if the buying organization understands the problematic areas of the SSI units and formulate their purchasing policy accordingly. This paper is trying to explore the satisfaction level of SSI suppliers with large scale selected manufacturing Indian industries acting as buyers. The satisfaction attributes and index of the SSI suppliers towards buyers and the buying organization measured by survey and structured interviewed method.

Manoj Kumar Mohanty; Prof (Dr) P Gahan

2011-01-01

366

The Epoch of Reionization in Models with Reduced Small Scale Power  

CERN Multimedia

Reducing the power on small scales relative to the `standard' LCDM model alleviates a number of possible discrepancies with observations, and is favored by the recent analysis of WMAP plus galaxy and Lyman-alpha forest data. Here, we investigate the epoch of reionization in several models normalized to WMAP on large scales, and with sufficiently reduced power on small scales to solve the halo concentration and substructure problems. These include a tilted model, the WMAP running-index model, and a Warm Dark Matter model. We assume that the Universe was reionized by stellar sources comprised of a combination of supermassive (~200 M_sun) Pop III stars and Pop II stars with a `normal' IMF. We find that in all of these models, structure formation and hence reionization occurs late, certainly at redshifts below ten, and more probably at z < 6. This is inconsistent (at 2 sigma) with the determination of z_reion ~ 17 from the WMAP temperature-polarization data and is only marginally consistent with SDSS quasar ob...

Somerville, R S; Livio, M; Somerville, Rachel S.; Bullock, James S.; Livio, Mario

2003-01-01

367

The small-scale species mobility in calcareous grasslands - example from southern Poland  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper I use the different measures of species mobility to describe the fine small-scale dynamics of calcareous grassland built mainly by perennial species and developed in the highly heterogeneous habitat of calcareous rocks. The community showed the low dynamics on a plot-scale (100 m2) and a high one on the scale of 1 m2. However, the studied species differed greatly in calculated indices: turnover rate, (T; 6-64), residence time (RT; 0.5-21.8 y) and carousel time (CT; 4-420 y) as well as the observed tendency to persistence on the spots (PERSIST) and their re-colonisation (AGAIN). This allowed to distinguish the three groups of species: (1) "core species" characterized by high frequency and low T and high CT and RT values, which determine the low dynamics of a community on the plot scale, (2) species with intermediate mobility rate and (3) the group with high mobility rate. The observed cumulative frequencies of all the studied species (CFobs) were much lower than expected under the random re-assignation model (CFRR). Moreover, they were also lower than those predicted by random immigration model (CFRI). The results showed that the "complex carousel" model rather than "single carousel" one explained better the small-scale dynamics of calcareous grasslands.

Wojciech B?ba

2005-01-01

368

A review of mercury exposure among artisanal small-scale gold miners in developing countries.  

UK PubMed Central (United Kingdom)

PURPOSE: Extraction of gold using mercury has been a way out of poverty for millions of people in developing countries. Artisanal small-scale gold mining (ASGM) has expanded during the last decades and is often carried out under primitive conditions. Thus, workers in this industry may be exposed to high levels of mercury and suffer from toxic effects from mercury exposure. The objective of this review was to provide an outline of the studies available on elemental mercury exposure among artisanal small-scale gold miners. METHODS: Searching the PubMed and Embase databases, 26 studies with a total of 3,005 exposed subjects and 442 controls across 14 different developing countries were found. Urine mercury levels were used as biomarkers of exposure. RESULTS: In general, the urine mercury levels were elevated and a considerable proportion of workers had urine mercury levels above existing guidelines. Exposed subjects were stratified into residents, miners, millers, smelters, and refiners, who by work task content were expected to be increasingly exposed to mercury. This group order did show a clear trend of increasing mercury levels. Mercury levels differed substantially between studies. Possible explanations include dissimilarities in gold extraction methods, use of protective devices, and selection of participants. CONCLUSIONS: This review provides evidence that artisanal gold miners and residents of the mining sites are exposed to mercury vapour to an extent where acute and long-term toxic effects of mercury are likely. Interventions aimed at reducing exposure and emission of mercury from ASGM are needed.

Kristensen AK; Thomsen JF; Mikkelsen S

2013-08-01

369

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

International Nuclear Information System (INIS)

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

2005-01-01

370

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

Energy Technology Data Exchange (ETDEWEB)

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.

Alakangas, E. [VTT Processes, Jyvaeskylae (Finland)

2005-07-01

371

Small-scale clumps in the galactic halo and dark matter annihilation  

CERN Document Server

Production of small-scale DM clumps is studied in the standard cosmological scenario with inflation-produced primeval fluctuation spectrum. A special attention is given to three following problems: (i) The mass spectrum of small-scale clumps with $M \\lesssim 10^3 M_{\\odot}$ is calculated with tidal destruction of the clumps taken into account within the hierarchical model of clump structure. Only 0.1 - 0.5% of small clumps survive the stage of tidal destruction in each logarithmic mass interval $\\Delta\\ln M\\sim1$. (ii) The mass distribution of clumps has a cutoff at $M_{min}$ due to diffusion of DM particles out of a fluctuation and free streaming at later stage. $M_{min}$ is a model dependent quantity. In the case the neutralino, considered as a pure bino, is a DM particle, $M_{min} \\sim 10^{-8} M_{\\odot}$. (iii) The evolution of density profile in a DM clump does not result in the singularity because of formation of the core under influence of tidal interaction. The radius of the core is $R_c \\sim 0.1 R$, w...

Berezinsky, Veniamin Sergeevich; Eroshenko, Y N; Eroshenko, Yu.

2003-01-01

372

Small scale ethanol production: design manual. [10 to 15 gallons per hour  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the project was to design, fabricate, and evaluate a small scale continuous ethanol plant. The scope of the study was to satisfy four specific objectives. The first objective was to design a small scale continuous distillation unit capable of producing 10 to 15 gallons per hour of 170 to 190 proof ethanol. A second objective was to economically fabricate the distillation unit. A third objective was to thoroughly evaluate the unit with emphasis on production potential, operation considerations, and energy balance. The fourth objective was to work with the Farm Bureau in identifying an organization that would place the unit in a production environment. The results of the study indicate that the distillation unit is capable of producing and average of 9 to 14 gallons per hour (based on alcohol percent in beer) of 174 proof ethanol. The energy ratio for distillation is a positive 3:1. Once the unit has reached steady state very little operator attention is required with the exception of periodically refluxing. Material cost of the plate column is approximately $5000. The unit could be built by an individual provided he is trained in welding and has the necessary shop equipment. 39 figures, 12 tables.

Adcock, L.E. II; Eley, M.H.; Schroer, B.J.

1981-09-01

373

High-temperature structural analysis modeling on the small-scale PCHE prototype  

Energy Technology Data Exchange (ETDEWEB)

Recently, a nuclear hydrogen production is gathering worldwide attention since it can produce hydrogen, a promising energy carrier, without an environment burden. The nuclear hydrogen program in Republic of Korea (ROK) is strongly considered to produce hydrogen by Sulfur-Iodine water-split hydrogen production processes. An intermediate loop that transports the nuclear heat to the hydrogen production process is necessitated for the nuclear hydrogen program as shown in Fig. 1. In the intermediate loop, the IHX (Intermediate Heat Exchanger) of VHTR (Very High Temperature Reactor) transfers the high heat of 950 .deg. C generated from the VHTR to a hydrogen production plant through a Hot Gas Duct. A PCHE (Printed Circuit Heat Exchanger) is considered as a candidate of the IHX of the nuclear hydrogen system in ROK. Recently, KAERI (Korea Atomic Energy Research Institute) established the small-scale gas loop for the performance test of VHTR components as shown in Fig. 2 and manufactured a small-scale prototype of PCHE in order to be tested in the gas loop. In this study, in order to investigate the macroscopic structural characteristics and behavior of the PCHE prototype under the test condition of the gas loop, FE (finite element) modeling, thermal analysis, and structural analysis on the PCHE prototype are conducted

Song, Kee Nam; Hong, S. D.; Lee, H. Y.; Park, H. Y. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2011-05-15

374

Design development of a static sunshade using small scale modeling technique  

Energy Technology Data Exchange (ETDEWEB)

The rising global demand for energy has triggered emphasis on conservation of energy. Buildings are one of the important energy consuming sectors. Passive solar architecture encompasses a wide range of strategies and options resulting in energy efficient building design and increased occupant's comfort. Passive solar design, aiming at increasing direct solar gains during winter period and to avoid overheating during summer period should make use of specific shading devices over energy efficient window. The static sunshades are most effective for solar control inside the buildings. Countries like India have composite climate, which can be classified under summer, winter and rainy season. Depending on the seasonal requirements, this paper introduces a new geometry of a static sunshade, designed by calculating the sun angles for the two dates. The static sun shading design methodology is validated with the help of small scale modelling experimentation technique, carried out in Pilani, Rajasthan (India). Although insulating materials can be used as a part of a building structure, its feasibility should be checked before particular application. In the present paper, the two small-scale experimental models of actual construction material with varying static sunshades, i.e. horizontal and the proposed one have been constructed and analyzed with the models of insulating material (Polyurethane Foam [PUF]). Depending upon the solar intersection over south facade wall, sunlit area and shaded area have been correlated with temperature inside the models to decide the effectiveness of the proposed sunshade. (author)

Ralegaonkar, R.V.; Rajiv Gupta [Birla Institute of Technology and Science, Rajasthan (India). Civil Engineering Group

2005-05-01

375

Intergenerational wealth transmission and the dynamics of inequality in small-scale societies.  

Science.gov (United States)

Small-scale human societies range from foraging bands with a strong egalitarian ethos to more economically stratified agrarian and pastoral societies. We explain this variation in inequality using a dynamic model in which a population's long-run steady-state level of inequality depends on the extent to which its most important forms of wealth are transmitted within families across generations. We estimate the degree of intergenerational transmission of three different types of wealth (material, embodied, and relational), as well as the extent of wealth inequality in 21 historical and contemporary populations. We show that intergenerational transmission of wealth and wealth inequality are substantial among pastoral and small-scale agricultural societies (on a par with or even exceeding the most unequal modern industrial economies) but are limited among horticultural and foraging peoples (equivalent to the most egalitarian of modern industrial populations). Differences in the technology by which a people derive their livelihood and in the institutions and norms making up the economic system jointly contribute to this pattern. PMID:19900925

Borgerhoff Mulder, Monique; Bowles, Samuel; Hertz, Tom; Bell, Adrian; Beise, Jan; Clark, Greg; Fazzio, Ila; Gurven, Michael; Hill, Kim; Hooper, Paul L; Irons, William; Kaplan, Hillard; Leonetti, Donna; Low, Bobbi; Marlowe, Frank; McElreath, Richard; Naidu, Suresh; Nolin, David; Piraino, Patrizio; Quinlan, Rob; Schniter, Eric; Sear, Rebecca; Shenk, Mary; Smith, Eric Alden; von Rueden, Christopher; Wiessner, Polly

2009-10-30

376

Intergenerational wealth transmission and the dynamics of inequality in small-scale societies.  

UK PubMed Central (United Kingdom)

Small-scale human societies range from foraging bands with a strong egalitarian ethos to more economically stratified agrarian and pastoral societies. We explain this variation in inequality using a dynamic model in which a population's long-run steady-state level of inequality depends on the extent to which its most important forms of wealth are transmitted within families across generations. We estimate the degree of intergenerational transmission of three different types of wealth (material, embodied, and relational), as well as the extent of wealth inequality in 21 historical and contemporary populations. We show that intergenerational transmission of wealth and wealth inequality are substantial among pastoral and small-scale agricultural societies (on a par with or even exceeding the most unequal modern industrial economies) but are limited among horticultural and foraging peoples (equivalent to the most egalitarian of modern industrial populations). Differences in the technology by which a people derive their livelihood and in the institutions and norms making up the economic system jointly contribute to this pattern.

Borgerhoff Mulder M; Bowles S; Hertz T; Bell A; Beise J; Clark G; Fazzio I; Gurven M; Hill K; Hooper PL; Irons W; Kaplan H; Leonetti D; Low B; Marlowe F; McElreath R; Naidu S; Nolin D; Piraino P; Quinlan R; Schniter E; Sear R; Shenk M; Smith EA; von Rueden C; Wiessner P

2009-10-01

377

THE SMALL-SCALE DYNAMO AND NON-IDEAL MAGNETOHYDRODYNAMICS IN PRIMORDIAL STAR FORMATION  

International Nuclear Information System (INIS)

We study the amplification of magnetic fields during the formation of primordial halos. The turbulence generated by gravitational infall motions during the formation of the first stars and galaxies can amplify magnetic fields very efficiently and on short timescales up to dynamically significant values. Using the Kazantsev theory, which describes the so-called small-scale dynamo—a magnetohydrodynamical process converting kinetic energy from turbulence into magnetic energy—we can then calculate the growth rate of the small-scale magnetic field. Our calculations are based on a detailed chemical network and we include non-ideal magnetohydrodynamical effects such as ambipolar diffusion and Ohmic dissipation. We follow the evolution of the magnetic field up to larger scales until saturation occurs on the Jeans scale. Assuming a weak magnetic seed field generated by the Biermann battery process, both Burgers and Kolmogorov turbulence lead to saturation within a rather small density range. Such fields are likely to become relevant after the formation of a protostellar disk and, thus, could influence the formation of the first stars and galaxies in the universe.

2012-08-01

378

Effect of water purification process in radioactive content: analysis on small scale purification plants  

International Nuclear Information System (INIS)

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)

2009-01-01

379

Investigation of Be/Cu joints via HHF tests of small-scale mockups  

Energy Technology Data Exchange (ETDEWEB)

Beryllium-copper (Be/Cu) joints in divertor components work under cyclic heat loads. To develop reliable joints small-scale mockups are fabricated by divertor technologies and tested under the divertor conditions. One of the critical damaging factors that exist in the divertor and have to be simulated is thermocyclic heat loads in the range of 1-15 MW/m{sup 2}. This work presents the divertor mockups that have beryllium tiles with different dimensions (5 x 5 - 44 x 44) mm{sup 2} brazed with copper alloy heat sink. The electron beam was used to braze these mockups so as to decrease the formation of brittle intermetallic layers. The description of mockups design, geometry of armour tiles and fabrication techniques are presented in the paper. The results of screening and thermocyclic tests of these mockups in the heat flux range of 2-12 MW/m{sup 2} with a number of cycles {approx}10{sup 3} are presented. The results of metallographic analysis are also presented. The results of fabrication and testing with small-scale mockups for first wall application are also described. (author)

Giniatulin, R.; Gervash, A.; Komarov, V.L.; Litunovsky, N.; Mazul, I.; Yablokov, N. [Efremov Inst., St. Petersburg (Russian Federation)

1998-01-01

380

A model for rapid stochastic distortions of small-scale turbulence  

Science.gov (United States)

We present a model describing the evolution of the small-scale Navier Stokes turbulence due to its stochastic distortion by much larger turbulent scales. This study is motivated by numerical findings (Laval et al. Phys. Fluids vol. 13, 2001, p. 1995) that such interactions of separated scales play an important role in turbulence intermittency. We introduce a description of turbulence in terms of the moments of k-space quantities using a method previously developed for the kinematic dynamo problem (Nazarenko et al. Phys. Rev. E vol. 68, 2003, 0266311). Working with the k-space moments allows us to introduce new useful measures of intermittency such as the mean polarization and the spectral flatness. Our study of the small-scale two-dimensional turbulence shows that the Fourier moments take their Gaussian values in the energy cascade range whereas the enstrophy cascade is intermittent. In three dimensions, we show that the statistics of turbulence wavepackets deviates from Gaussianity toward dominance of the plane polarizations. Such turbulence is formed by ellipsoids in the k-space centred at its origin and having one large, one neutral and one small axis with the velocity field pointing parallel to the smallest axis.

Dubrulle, B.; Laval, J.-P.; Nazarenko, S.; Zaboronski, O.

2004-12-01

 
 
 
 
381

High-temperature structural analysis modeling on the small-scale PCHE prototype  

International Nuclear Information System (INIS)

Recently, a nuclear hydrogen production is gathering worldwide attention since it can produce hydrogen, a promising energy carrier, without an environment burden. The nuclear hydrogen program in Republic of Korea (ROK) is strongly considered to produce hydrogen by Sulfur-Iodine water-split hydrogen production processes. An intermediate loop that transports the nuclear heat to the hydrogen production process is necessitated for the nuclear hydrogen program as shown in Fig. 1. In the intermediate loop, the IHX (Intermediate Heat Exchanger) of VHTR (Very High Temperature Reactor) transfers the high heat of 950 .deg. C generated from the VHTR to a hydrogen production plant through a Hot Gas Duct. A PCHE (Printed Circuit Heat Exchanger) is considered as a candidate of the IHX of the nuclear hydrogen system in ROK. Recently, KAERI (Korea Atomic Energy Research Institute) established the small-scale gas loop for the performance test of VHTR components as shown in Fig. 2 and manufactured a small-scale prototype of PCHE in order to be tested in the gas loop. In this study, in order to investigate the macroscopic structural characteristics and behavior of the PCHE prototype under the test condition of the gas loop, FE (finite element) modeling, thermal analysis, and structural analysis on the PCHE prototype are conducted

2011-01-01

382

Small-scale testing of in-core fast reactor materials  

International Nuclear Information System (INIS)

Part of the Fuel Cycle R and D (FCRD) initiative in the USA is to investigate materials for high dose application. While mechanical testing on large samples delivers direct engineering data, these types of tests are only possible if enough sample material and required hot cell capabilities are available. Small-scale materials testing methods in addition to large-scale materials testing allows insight on the same specimen and direct probing into areas of interest which are not accessible otherwise. In order to establish an empirical and research-based relationship between small-scale and large-scale materials testing, several different mechanical testing techniques were conducted on the same specimen irradiated in the Swiss spallation source irradiation program (STIP) at the Swiss spallation source (SINQ) at the Paul Scherrer Institute (PSI) up to a dose of 19 dpa. It is shown that the yield strength measured by tensile testing, microcompression testing and microhardness testing all show the same trend. In addition, focused ion beam (FIB)-based techniques also are used to produce local electrode atom probe (LEAP) samples. This procedure allows cutting samples of such a small size that no radioactivity on the prepared sample can be measured. (author)

2011-01-01

383

The Origin of the Interstellar Turbulence and Small Scale Structures of Molecular Clouds  

Science.gov (United States)

In order to study the origin of the interstellar turbulence, detailed observations in the CO J = 1–0 and 3–2 lines have been carried out in an interacting region of a molecular cloud with an H II region by the Nobeyama 45m and ASTE telescopes. As a result, several 1,000 to 10,000 AU scale cloudlets with small velocity dispersion (?V ˜ 0.6 km s-1) are detected, whose systemic velocities have a relatively large scatter of a few km s-1. It is suggested that the cloud is composed of small-scale dense and cold structures and their overlapping effect makes it appear to be a turbulent entity as a whole. This picture strongly supports the two-phase model of turbulent medium driven by thermal instability proposed previously. On the surface of the present cloud, the turbulence is likely to be driven by thermal instability following ionization shock compression and UV irradiation. Those small scale structures have a relatively high CO line ratio of J=3–2 to 1–0, 1 ? R3–2/1–0 ? 2. The large velocity gradient analysis implies that the 0.6 km s-1 width component cloudlets have an average density of 103–4 cm–3, which is relatively high at cloud edges, but their masses are only ? 0.05 M?.

Tachihara, K.

2013-10-01

384

Statistical Significance of Small Scale Anisotropy in Arrival Directions of Ultra-High Energy Cosmic Rays  

CERN Multimedia

Recently, the High Resolution Fly's Eye (HiRes) experiment claims that there is no small scale anisotropy in the arrival distribution of ultra-high energy cosmic rays (UHECRs) above $E>10^{19}$ eV contrary to the Akeno Giant Air Shower Array (AGASA) observation. In this paper, we discuss the statistical significance of this discrepancy between the two experiments. We calculate arrival distribution of UHECRs above $10^{19}$ eV predicted by the source models constructed using the Optical Redshift Survey galaxy sample. We apply the new method developed by us for calculating arrival distribution in the presence of the galactic magnetic field. The great advantage of this method is that it enables us to calculate UHECR arrival distribution with lower energy ($\\sim 10^{19}$ eV) than previous studies within reasonable time by following only the trajectories of UHECRs actually reaching the earth. It has been realized that the small scale anisotropy observed by the AGASA can be explained with the source number density ...

Yoshiguchi, H; Sato, K; Yoshiguchi, Hiroyuki; Nagataki, Shigehiro; Sato, Katsuhiko

2004-01-01

385

Small scale CHP: Alternative integration forms in the Danish energy system  

International Nuclear Information System (INIS)

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)

2003-01-01

386

Small-scale Structure of the Interstellar Medium toward ? Oph Stars: Diffuse Band Observations  

Science.gov (United States)

We present an investigation of small-scale structure in the distribution of large molecules/dust in the interstellar medium through observations of diffuse interstellar bands (DIBs). High signal-to-noise optical spectra were recorded toward the stars ? Oph A, B, C, and DE using the University College London Echelle Spectrograph on the Anglo-Australian Telescope. The strengths of some of the DIBs are found to differ by about 5%-9% between the close binary stars ? Oph A and B, which are separated by a projected distance on the sky of only c. 344 AU. This is the first star system in which such small-scale DIB strength variations have been reported. The observed variations are attributed to differences between a combination of carrier abundance and the physical conditions present along each sightline. The sightline toward ? Oph C contains relatively dense, molecule-rich material and has the strongest ??5850 and 4726 DIBs. The gas toward DE is more diffuse and is found to exhibit weak "C2" (blue) DIBs and strong yellow/red DIBs. The differences in diffuse band strengths between lines of sight are, in some cases, significantly greater in magnitude than the corresponding variations among atomic and diatomic species, indicating that the DIBs can be sensitive tracers of interstellar cloud conditions.

Cordiner, M. A.; Fossey, S. J.; Smith, A. M.; Sarre, P. J.

2013-02-01

387

Harmonic Propagation and Interaction Evaluation between Small-Scale Wind Farms and Nonlinear Loads  

Directory of Open Access Journals (Sweden)

Full Text Available Distributed generation is a flexible and effective way to utilize renewable energy. The dispersed generators are quite close to the load, and pose some power quality problems such as harmonic current emissions. This paper focuses on the harmonic propagation and interaction between a small-scale wind farm and nonlinear loads in the distribution grid. Firstly, by setting the wind turbines as P – Q(V) nodes, the paper discusses the expanding Newton-Raphson power flow method for the wind farm. Then the generalized gamma mixture models are proposed to study the non-characteristic harmonic propagation of the wind farm, which are based on Gaussian mixture models, improved phasor clustering and generalized Gamma models. After the integration of the small-scale wind farm, harmonic emissions of nonlinear loads will become random and fluctuating due to the non-stationary wind power. Furthermore, in this paper the harmonic coupled admittance matrix model of nonlinear loads combined with a wind farm is deduced by rigorous formulas. Then the harmonic propagation and interaction between a real wind farm and nonlinear loads are analyzed by the harmonic coupled admittance matrix and generalized gamma mixture models. Finally, the proposed models and methods are verified through the corresponding simulation models in MATLAB/SIMULINK and PSCAD/EMTDC.

Guang-Long Xie; Bu-Han Zhang; Yan Li; Cheng-Xiong Mao

2013-01-01

388

Analysis of Strategic Petroleum Reserve (SPR) small-scale cavern drawdowns  

Energy Technology Data Exchange (ETDEWEB)

The United States Strategic Petroleum Reserve (SPR) consists primarily of oil storage caverns leached within salt domes along the US Gulf Coast. Water which is not salt saturated is injected into the caverns in order to remove the oil. This results in additional cavern leaching. Previous cavern analyses have addressed the leaching associated with complete withdrawal cycles. This report describes the deveopment of a simplified model for assessing the magnitude of the leaching expected from small-scale drawdowns. These small drawdowns may result from very short term requirements for oil from the Reserve which do not result in complete cavern withdrawals, from periodic testing of Reserve readiness, or from special operation or maintenance requirements. Both a graphical solution technique and one designed for use on a personal computer are presented. In addition, an application of the techniques to an evaluation of existing SPR caverns is presented. Finally, conclusions and observations are given for minimizing leaching impacts in the selection of caverns for small-scale drawdowns. 8 refs., 14 figs., 2 tabs.

Biringer, K.L.

1985-11-01

389

An Automatic Method for Extreme-Ultraviolet Dimmings Associated with Small-Scale Eruption  

CERN Multimedia

Small-scale extreme ultraviolet (EUV) dimming often surrounds sites of energy release in the quiet Sun. This paper describes a method for the automatic detection of these small-scale EUV dimmings using a feature based classifier. The method is demonstrated using sequences of 171 A images taken by STEREO/EUVI on 13 June 2007 and by SDO/AIA on 27 August 2010. The feature identification relies on recognizing structure in sequences of space-time 171\\AA\\ images using the Zernike moments of the images. The Zernike moments space-time slices with events and non-events are distinctive enough to be separated using a Support Vector Machine (SVM) classifier. The SVM is trained using 150 event and 700 non-event space-time slices. We find a total of 1217 events in the EUVI images and 2064 events in the AIA images on the days studied. Most of the events are found between latitudes -35 degree and +35 degree. The sizes and expansion speeds of central dimming regions are extracted using a region grow algorithm. The histograms ...

Alipour, N; Innes, D E

2011-01-01

390

AN AUTOMATIC DETECTION METHOD FOR EXTREME-ULTRAVIOLET DIMMINGS ASSOCIATED WITH SMALL-SCALE ERUPTION  

International Nuclear Information System (INIS)

Small-scale extreme-ultraviolet (EUV) dimming often surrounds sites of energy release in the quiet Sun. This paper describes a method for the automatic detection of these small-scale EUV dimmings using a feature-based classifier. The method is demonstrated using sequences of 171 ? images taken by the STEREO/Extreme UltraViolet Imager (EUVI) on 2007 June 13 and by Solar Dynamics Observatory/Atmospheric Imaging Assembly on 2010 August 27. The feature identification relies on recognizing structure in sequences of space-time 171 ? images using the Zernike moments of the images. The Zernike moments space-time slices with events and non-events are distinctive enough to be separated using a support vector machine (SVM) classifier. The SVM is trained using 150 events and 700 non-event space-time slices. We find a total of 1217 events in the EUVI images and 2064 events in the AIA images on the days studied. Most of the events are found between latitudes –35° and +35°. The sizes and expansion speeds of central dimming regions are extracted using a region grow