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  1. 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)

    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 attachedeir 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)

  2. A gender perspective on empowerment of women small scale farmers

    OpenAIRE

    Friis-Rasmussen, Clara

    2012-01-01

    The research described in this report was conducted during my internship March-June 2012 at the NGO Surplus People Project based in Cape Town, South Africa. The research is using a constructivist approach in analyzing the potential of the organization to improve it’s facilitation of women empowerment in the local rural areas through an increased focus on adressing gender specific issues related to being a woman small scale farmer. The research has been conducted with various qualitati...

  3. Jatropha and Sustainable Livelihood of Small-scale Farmers

    OpenAIRE

    Ladefoged, Tanja, Helle Momsen Fredslund; Hansen, Rasmus Bo

    2009-01-01

    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 biofuel use. The content of this thesis is a determination of the possible livelihood impacts from a jatropha production, through a case in Zambia where 25.000 small-scale farmers are involved in...

  4. Small-scale Farmer’s Perception on the Impact of Grazing Livestock Animals on Crop Production in Abuja, Nigeria

    OpenAIRE

    Ajah Julius

    2012-01-01

    The production of crops and livestock animals in Nigeria is not mutually exclusive hence a study was conducted to determine small-scale crop farmers’ perception of the impact of grazing livestock animals like cattle, goat, sheep and domestic fowls on crop production in Abuja, Nigeria. A multi-stage technique was adopted for sample selection while semi-structured questionnaires were used for data collection. A total of 384 small-scale crop farmers were randomly interviewed in four agricultur...

  5. Tanzania’s Small-Scale Sunflower Farmers: Upgrading the Value Chain

    OpenAIRE

    Enock S. Ugulumu; Eno L. Inanga

    2013-01-01

    A questionnaire using a psychometric scale investigated how small-scale sunflower farmers perceive the role of building relationships based on demand-driven upgrades, such as knowledge, skills, technology, and support services within the value chain. The study focused on small-scale sunflower farmers in the Singida region of Tanzania. The survey was conducted in twelve Agricultural Marketing Cooperatives (AMCOs) with 229 respondents. The respondents had positive opinions about creating co...

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

    OpenAIRE

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

    2011-01-01

    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 pha...

  7. Constraints and Challenges Facing the Small Scale Farmers in Limpopo Province, South Africa

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    Sylvester Mpandeli

    2014-03-01

    Full Text Available Macro- and micro-structural constraints, including those linked to and exacerbated by historical, natural and financial factors are some of the many stressors facing small-scale farmers in Limpopo Province. The challenge is to co-design ways to effectively manage these constraints with development actions. Small scale farmers in South Africa are still facing major challenges in the agricultural sector. In this paper some of the challenges faced by small-scale farmers in the Limpopo Province have been identified. Some of the challenges found during the formal surveys and focus group meetings in the Tshakhuma, Rabali and Tshiombo areas were those linked to financial, assets, land ownership and biophysical factors. Specific constraints included: (a Market information and market access; (b Price of inputs, for example fertilizer and herbicides; (c Availability of inputs; (d Irrigation; (e Cost of transport, and Natural constraint.

  8. Assessing Farm Record Keeping Behaviour among Small-Scale Poultry Farmers in the Ga East Municipality

    OpenAIRE

    Enoch Kwame Tham-Agyekum; Patrick Appiah; Fred Nimoh

    2010-01-01

    The study sought to investigate the farm record keeping behaviour among small-scale poultry farmers in the GaEast Municipality. Data was collected by the use of the simple random sampling technique. All the poultryfarmers interviewed kept at least production and financial records. The chi-square test of independence showedthat farm record keeping was independent of age, educational level, experience in poultry farming, farmer status,number of birds owned by respondents and respondents’ memb...

  9. Tanzania’s Small-Scale Sunflower Farmers: Upgrading the Value Chain

    Directory of Open Access Journals (Sweden)

    Enock S. Ugulumu

    2013-04-01

    Full Text Available A questionnaire using a psychometric scale investigated how small-scale sunflower farmers perceive the role of building relationships based on demand-driven upgrades, such as knowledge, skills, technology, and support services within the value chain. The study focused on small-scale sunflower farmers in the Singida region of Tanzania. The survey was conducted in twelve Agricultural Marketing Cooperatives (AMCOs with 229 respondents. The respondents had positive opinions about creating core competencies, concluding that adopting new capabilities, especially with tangible assets such as extension officers, financing, warehouses, and technology, can lead to improved productivity and quality. The information flow from sunflower buyers and consumers is crucial for creating a positive image and hence creating value for farmers. Farmers require negotiating skills that could be attained through improved associations or cooperatives. Respondents also indicated positive benefits if the sector¾and its risks and income¾further diversifies. However, farmers showed weaknesses and failures to: Provide inputs to the sector’s upgrading processes; Form strong, capable, and cohesive associations or cooperatives that can enhance bargaining power for small-scale farmers; Improve infrastructure such as roads and warehouses.

  10. Impact of weather insurance on small scale farmers: A natural experiment

    OpenAIRE

    Dietrich, Stephan; Ibanez, Marcela

    2015-01-01

    This paper explores the impacts of traditional agricultural insurance that offers protection against climatic shocks on small-scale tobacco farmers in Colombia. We analyze the impacts of access to the insurance on household financial outcomes after a period of severe climatic events that caused substantial crop failures. Our identification strategy benefits from a natural experimental setup of the form in which the insurance was launched. We find that tobacco producers with access to the insu...

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

    Scientific Electronic Library Online (English)

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

    Full Text Available 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 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

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

    OpenAIRE

    Mburu, P. T.; Massimo, S. K.

    2005-01-01

    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 industrie...

  13. Use of ICT in Securing Marketing Information among Small Scale Farmers in Niger State, Nigeria

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    Job N. Nmadu

    2013-04-01

    Full Text Available This study examined the use of information communication technology (ICT on securing marketing information among small scale farmers in Niger State, Nigeria. Data were obtained from 90 respondents through the use of structured questionnaire. The information collected was analyzed using descriptive statistics and multinomial logistic regression technique. Results of the analysis showed that majority of the respondents were in their active age of production and were married. Most of the respondents obtained their information from radio, television, and newspaper. The finding also indicated that the years spent in school and not the educational achievement is what is likely to increase the probability of awareness. Problems identified with regards to the usage of ICTs by the respondents include language barrier, poverty, and illiteracy. It was therefore recommended that government and nongovernmental organizations should collaborate to include ICT workshop and training in farmer education programmes, encourage programmes like NYSC ICT volunteer group, and translate technology to local languages.

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

    OpenAIRE

    Sharon Groenmeyer

    2013-01-01

    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 ...

  15. Detection of Transgenes in Local Maize Varieties of Small-Scale Farmers in Eastern Cape, South Africa

    OpenAIRE

    Iversen, Marianne; Grønsberg, Idun M.; van den Berg, Johnnie; Fischer, Klara; Aheto, Denis Worlanyo; Bøhn,Thomas

    2014-01-01

    Small-scale subsistence farmers in South Africa have been introduced to genetically modified (GM) crops for more than a decade. Little is known about i) the extent of transgene introgression into locally recycled seed, ii) what short and long-term ecological and socioeconomic impacts such mixing of seeds might have, iii) how the farmers perceive GM crops, and iv) to what degree approval conditions are followed and controlled. This study conducted in the Eastern Cape, South Africa, aims primar...

  16. Resource Use and Technical Efficiency of Small Scale Poultry Farmers in Enugu State, Nigeria: A Stochastic Frontier Analysis

    OpenAIRE

    P.C. IKE

    2011-01-01

    The study examined the factors that affect poultry production among small scale poultry farmers in Enugu State, Nigeria. Thirty six respondents were sampled from a list of poultry farmers derived from Enugu State Agricultural Development Programme Office. The Cob Douglas stochastic production function was used to determine factors that affect poultry output as well as the factors that affect the technical efficiency of poultry production. Farm size (p = 0.05), capital input (p = 0.01), labour...

  17. Ulcer Type of Disease in the Fishes of Small-Scale Farmer`s Pond in Bangladesh

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    M.B.R. Chowdhury

    2003-01-01

    Full Text Available Studies were conducted to investigate ulcer type of disease in the small-scale rural poor fish farmer?s pond and to suggest a low-cost treatment measure. In total 20 ponds of 10 different sites were selected in the district of Mymensingh for treatment and control ones. Fishes were sampled on monthly basis starting from September 2000 and continued until April 2001 to examine their disease condition. Ulcer type of disease with expression of lesions was detected by spot observation followed by laboratory examination. A number of suspective bacterial pathogens were recovered from the lesions and kidney of diseased fishes, viz., Cirrhinus cirrhosus, Labeo rohita, Catla catla, Barbodes gonionotus, Pangasius hypophthalamus. Fungal isolates especially Aphanomyces sp., Saprolegnia sp. and Achlya sp. were recovered from the lesions and affected muscles of the sampled fishes. A number of recovered bacterial isolates were detected as pathogenic among which Aeromonas hydrophila, Ah-11 and A. veronii biover sobria were recognized as high virulent isolates. In the case of fungal isolates Aphanomyces sp. and Saprolegnia sp. were detected as pathogenic. Prevalence of disease outbreak was found to be very low where preventive treatment measures were taken with salt and lime (1:1, 1 kg/decimal. In the winter months (January and February, the disease outbreaks were found to be very high in the non-treated (control ponds, whereas in the treated ponds prevalence of infection were significantly low. In laboratory based treatment trial, antibiotic renamycin was found to be effective against bacterial invasion at a dose of 50mg/kg body wt/day applying for five days. In the case of fungal infection, the diseased fishes were found to be cured within five days by one hour bath in 0.5% salt and lime suspension at a ratio of 1:1 applying for 3 days.

  18. Demand for Agricultural Extension Services among Small-Scale Maize Farmers: Micro-Level Evidence from Kenya

    Science.gov (United States)

    Gido, Eric O.; Sibiko, Kenneth W.; Ayuya, Oscar I.; Mwangi, Joseph K.

    2015-01-01

    Purpose: The objective of the study was to determine the level and determinants of demand for extension services among small-scale maize farmers in Kenya. Design/methodology/approach: Based on an exploratory research design, primary data were collected from a sample of 352 households through face-to-face interviews. Focus group discussions were…

  19. The Influence of Enterprise Diversification on Household Food Security among Small-Scale Sugarcane Farmers: A Case Study of Muhoroni Division, Nyando District, Kenya

    Science.gov (United States)

    Muthoni Thuo, Caroline

    2011-01-01

    This paper examines the levels of household food security and the influence of enterprise diversification on household food security among small-scale sugarcane farmers in Muhoroni division, Nyando District, Kenya. A cross-sectional research design was used in this study. The population consisted of small-scale sugarcane farmers who grow sugarcane…

  20. The impact of training using a structured primary animal health care model on the skills of rural small scale farmers

    OpenAIRE

    Moerane, Rebone

    2014-01-01

    Primary animal health care (PAHC) programs are aimed at the provision of basic animal health services at local level. No single approach has emerged as the one of choice. The aim of this study was to evaluate the impact of training using the PAHC model developed by Afrivet Training Service, on the skills of small scale rural farmers. Seventy nine farmers were selected randomly from Makapanstad, Ratjiepane and Mnisi area using a statistical software EpiCalc 2000 v1.02. The selec...

  1. Ixodid ticks on indigenous goats owned by small-scale farmers in four communal grazing areas in South Africa

    OpenAIRE

    B.A.J. du Plessis; Stewart, C. G.; I.G. Horak; Tice, G.A.; Bryson, N.R.

    2012-01-01

    Indigenous goats belonging to small-scale farmers in 4 communal grazing areas in South Africa were sampled for ixodid ticks during the period September 1991 to May 1993. Three of these areas were in the North West Province (Rietgat, Madinyane and Bethany), and one in Mpumalanga Province (Geluk). No tick control was practised unless requested by the owners. Seven ixodid tick species, of which the majority were immature ticks, were collected from the goats in North West Province. Ambl...

  2. Ixodid ticks on cattle belonging to small-scale farmers at 4 communal grazing areas in South Africa

    OpenAIRE

    Bryson, N.R.; Tice, G.A.; I.G. Horak; Stewart, C. G.; B.J.A. Du Plessis

    2012-01-01

    Ixodid ticks were collected during the period September 1991 to August 1993 from cattle belonging to small-scale farmers utilising 4 communal grazing areas. Three of these were in North West Province and 1 in Mpumalanga province, South Africa. Ten tick species were collected in North West Province and 7 in Mpumalanga. The adults of Amblyomma hebraeum, Rhipicephalus appendiculatus and Rhipicephalus evertsi evertsi were most numerou...

  3. Small scale farmers’ access to and participation in markets : The case of the P4P program in western Kenya

    OpenAIRE

    Skjo?ldevald, Maja

    2012-01-01

    The purpose of this thesis is to understand how small scale farmers navigate the market to access and participate in the formal maize market to improve their revenue, utilising the case of the P4P program inKenya. The empirical material was collected during fieldwork in Kenya. Qualitative methods were found to be the most suitable for this thesis. The methods that was utilised were a case study strategy, semi structured interviews, focus groups, observations and analysis of secondary sources....

  4. Climate Variability and Land-use Change in Danangou Watershed, China. Examples of Small-Scale Farmers' Adaptation

    Energy Technology Data Exchange (ETDEWEB)

    Hageback, J.; Sundberg, J. [Department of Earth Sciences, Goeteborg University, Goeteborg (Sweden); Ostwald, M. [Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 54-1411, 77 Mass Ave, MA, 02139 (United States); Chen, D. [Laboratory for Climate Studies at National Climate Center, China Meteorological Administration, Beijing (China); Yun, X. [Department of Resource and Environment Sciences, Beijing Normal University, Beijing (China); Knutsson, P. [Section of Human Ecology, Goeteborg University, Goeteborg (Sweden)

    2005-09-01

    With global concern on climate change impacts, developing countries are given special attention due their susceptibility. In this paper, change and variability in climate, land use and farmers' perception, adaptation and response to change are examined in Danangou watershed in the Chinese Loess Plateau. The first focus is to look at how climate data recorded at meteorological stations recently have evolved, and how farmers perceived these changes. Further, we want to see how the farmers respond and adapt to climate variability and what the resulting impact on land use is. Finally, other factors causing change in land use are considered. Local precipitation and temperature instrumental data and interview data from farmers were used. The instrumental data shows that the climate is getting warmer and drier, the latter despite large interannual variability. The trend is seen on the local and regional level. Farmers' perception of climatic variability corresponds well with the data record. During the last 20 years, the farmers have become less dependent on agriculture by adopting a more diversified livelihood. This adaptation makes them less vulnerable to climate variability. It was found that government policies and reforms had a stronger influence on land use than climate variability. Small-scale farmers should therefore be considered as adaptive to changing situations, planned and non-consciously planned.

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

    Directory of Open Access Journals (Sweden)

    Jonathan Kuje Yohanna

    2011-06-01

    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.

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

    DEFF Research Database (Denmark)

    Buch-Hansen, Mogens

    2012-01-01

    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.

  7. Socio Economic Determinants of the Adoption of Integrated Natural Resource Management Technologies by Small Scale Farmers: Evidence from Western Kenya

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    Isaiah K. Okuthe

    2013-09-01

    Full Text Available The main aim of the study was to examine the influence of socio economic factors on the adoption of Integrated Natural Resource Management (INRM technologies that could restore soil fertility. INRM bridges the gap between high external input agriculture and extreme forms of traditional low external input agriculture. The main components of INRM in Ndhiwa division are chemical fertilizer, animal manure, green manure, stover lines and agro forestry. However the adoption of these technologies appears to be low resulting to probably the low production. It is not understood well why farmers who rely on agriculture for their livelihoods, either do not adopt or adopt the technologies and then abandon. An ex-post-facto survey design which utilized both qualitative and quantitative methods of data collection was used in the study. For quantitative data collection, a sample of 220 small scale farmers selected using systematic random sampling from the small scale farmers in the Division were engaged. For qualitative data, 40 small scale farmers and 37 Key Informants selected using purposive sampling from the division were used. Results of the study indicated that households education status, gender, access to credit and membership in social groups were important variables which had positively and significantly influenced adoption of INRM technologies. The overall finding of the study underlined the high importance of institutional support in the areas of extension, strengthening social groups and improving market and credit condition to enhance adoption of INRM technologies. The study will be significant to planners, policy makers, researchers, extension and farmers to build the case for interventions on INRM within the development sector for improved and sustainable agriculture and rural development.

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

    Directory of Open Access Journals (Sweden)

    Sharon Groenmeyer

    2013-04-01

    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.

  9. Hygienic aspects of livestock manure management and biogas systems operated by small-scale pig farmers in Vietnam

    DEFF Research Database (Denmark)

    Luu, Huong Quynh; Madsen, Henry

    2014-01-01

    Biogas digesters are widely promoted and increasingly used to treat and generate gas from pig slurry worldwide. The objective of this study was to describe manure management practices with focus on biogas digestion among small scale pig farmers in Hue (50 farmers) and Hanoi (96 farmers) and to assess fecal contamination levels in biogas effluent. Results showed that 84% of the farmers in Hanoi and 42% in Hue used both pig slurry and human excreta for biogas production. Biogas digestion only reduced E. coli concentrations by 1 to 2 log units to 3.70±0.84 Escherichia coli (log) cfu/ml on average in effluent as compared with raw slurry. Biogas effluent was commonly used to fertilize vegetables or discharged directly into the garden or aquatic recipients. Reduced problems with bad smells and flies were reported as main reasons for establishing a biogas digester. Further studies are needed to assess human and animal health hazards associated with the discharge and use of biogas effluent from small-scale biogas systems. © 2013 Elsevier B.V.

  10. Efficiency indices and indicators of poor performance among emerging small-scale pig farmers in the Limpopo Province, South Africa.

    Science.gov (United States)

    Mokoele, Japhta M; Spencer, B Tom; van Leengoed, Leo A M G; Fasina, Folorunso O

    2014-01-01

    Limpopo is a very important area for pig production in terms of animal populations and contributions to transboundary animal disease spread. Emerging small-scale pig farmers (ESSPF) are being encouraged to establish operations and spread in South Africa; however, for these farmers to perform optimally, they need to understand the basics of animal agriculture and contribute to enhancing biosecurity and efficient production systems. In the present study, the limitations to efficient production amongst ESSPF were evaluated and some improvements were suggested. It was found that the ESSPF are dominated by males and include a large percentage of older persons. A total of 26.54% of these farmers have post-matriculation qualifications. Undefined and indigenous breeds still dominate their animal genetics. The animal health technicians are the preferred channels by which farmers report diseases to the authorities (52.47%) and only one out of five (20.37%) will preferably report a disease situation direct to a veterinarian. These farmers do not vaccinate their stock, and knowledge of biosecurity is poor. Antimicrobials, especially tetracyclines, are abused. Animals that are slaughtered within the community or sold at local sale points, pension pay stations and auction markets are likely candidates for disease spread. It is recommended that the younger generations are retained and incentivised in animal agriculture. Improved training on management, health, biosecurity and better market access must be provided for the ESSPF, whilst efforts should made to consolidate these farmers into small cooperatives. The current government agricultural support system will need to be reworked to benefit the resource-poor farmers. Collaborative efforts in disease reporting and management among veterinarians, animal health technicians and extension officers will become necessary. Finally, the creation of a progressive quality grading system for ESSPF should be planned by the industry and this should be attached to a reward system that will encourage these farmers to target good farming practice. PMID:25685963

  11. Payments for Environmental Services as source of development funding for small-scale farmers in northern Namibia: preliminary results

    Science.gov (United States)

    Angombe, Simon; Bloemertz, Lena; Käch, Simon; Böller, Marianne; Kuhn, Nikolaus J.

    2014-05-01

    Studies in Africa suggest that improving Soil Organic Carbon (SOC) on cropland soils increases yields, but also offers the opportunity of earning carbon credits. However, at the current price for a ton of carbon, the potential to earn significant carbon credits is limited. Therefore carbon storage should not be seen as a goal in itself. Potential for earning carbon credits and generating further benefits lies in an integrated approach to landscape carbon management, including shrub land and pasture used for grazing and timber supply. Therefore, soil management has to be addressed from a holistic understanding of the livelihoods of small-scale farmers. This includes a detailed understanding of the constraints in farming, as well as the motivation behind farming. The aim of this study is the identification of intervention mechanisms to improve the livelihood of small scale-farmers and reducing land degradation with the support of Payments for Ecosystem Services (PES) in the communal regions of northern Namibia. The main objective of the first part of the field work was to develop an overview of soil quality, farm management and the constraints and motivations regarding farming. Initial results confirm the potential to increase productivity of land while at the same time building up landscape carbon stocks. They furthermore show the importance of carefully choosing the way new farming techniques are introduced, as many farmers are afraid of trying something new.

  12. Willingness to Adopt Certifications and Sustainable Production Methods among Small-Scale Cocoa Farmers in the Ashanti Region of Ghana

    Directory of Open Access Journals (Sweden)

    Robert Aidoo

    2015-01-01

    Full Text Available The main objective of this research project was to identify current cocoa production practices and determine the principal factors that affect the adoption of sustainable farming practices and socio-environmental certifications among small-scale cocoa farmers in Ghana. The study was conducted in two cocoa districts (Atwima Mponua and Ahafoano North in the Ashanti Region of Ghana. A combination of stratified, systematic and random sampling techniques was employed to select 439 cocoa producing households for the study. A standardized structured questionnaire was used to gather field data through personal interviews. Results showed that membership in farmers’ organizations, awareness of certification and size of cocoa farm were the main determinants of willingness to adopt sustainable cocoa production methods and certifications. Whereas membership in farmer-based organizations and awareness about different aspects related to certification had a significant positive effect on adoption of cocoa certification, farm size tended to have a significant negative effect on adoption of certification. Formation of cocoa farmers’ associations/organizations in various communities, creation of awareness about certification and continuous education of cocoa farmers are recommended to stimulate adoption of cocoa certification to achieve sustainability in the Ghanaian cocoa industry.

  13. An airtight paddy storage system for small-scale farmers in Sri Lanka

    OpenAIRE

    Adhikarinayake, T. B.; Mu?ller, J.; Oostdam, J. W. M.; Huisman, W.; Richards, P.

    2007-01-01

    The farmers in Sri Lanka's dry zone are the main contributors to the paddy production in the country. However, due to various reasons, they face difficulties in obtaining a reasonable income for their produce at harvesting time. According to the survey carried out in the paddy producing regions, it was found that one possible solution to reduce this problem is to enable the farmers to sell their produce at a time when prices are higher than at harvest time. To enable the farmers to keep their...

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

    OpenAIRE

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

    2011-01-01

    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 vari...

  15. Poultry production and rural poverty among small-scale farmers in Mzimba District of Malawi

    OpenAIRE

    Assa, Maganga

    2012-01-01

    This paper evaluates the role of participating in poultry production on household income and rural poverty in Mzimba district, Malawi. The study utilizes cross-sectional farm level household data collected in 2011. The paper computes income-based poverty measures and investigates their sensitivity to the use of different poverty lines. Robust poverty comparisons across the poultry and non-poultry farmers reveal that poverty is in fact higher for the non-poultry compared to the poultry farmers...

  16. Determinants of Market Participation among Small-scale Pineapple Farmers in Kericho County, Kenya

    OpenAIRE

    Sigei, Geoffrey; Bett, Hillary; Kibet, Lawrence

    2014-01-01

    Marketing agricultural produce is important amongst smallholder farmers because they derive benefits such as income and rural employment. In developing countries like Kenya, most smallholder farmers are characterized by poor market participation because they lack market information on pineapple marketing. In Bureti district; pineapples have been perceived to have high market value, resulting in trade-offs with staple food. Despite pineapples market value, its market participation has not been...

  17. EFFECT OF MICRO FINANCE ON POVERTY REDUCTION OF SMALL SCALE FARMERS OF PAKISTAN

    OpenAIRE

    Saeed, Zaheer Ahmad; Saeed, Rashid; Lodhi, Rab Nawaz

    2013-01-01

    This study revealed the impact of micro finance with regard to poverty alleviation, employment generation opportunities, upraise in the standards of living of the small farmers of Pakistan along with the access of such finances and their financial cost. Small farmers often rely on the loans and finance from the formal and informal sources of finance. There is low rate of sustainability in the micro finance sector. These schemes remain for a small time period. Another challenge is that there i...

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

    Directory of Open Access Journals (Sweden)

    P.T. Mburu

    2005-01-01

    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.

  19. Factors Limiting Small-Scale Farmers’ Access and Use of Tractors for Agricultural Mechanization in Abuja, North Central Zone, Nigeria

    Directory of Open Access Journals (Sweden)

    Ajah Julius

    2014-02-01

    Full Text Available The importance of tractor and its implements in agricultural mechanization necessitatedthis study. The main objective is to identify factors limiting small-scale farmers’ access anduse of tractors for farm mechanization in Abuja, Nigeria. To effectively cover the studyarea, a simple random technique was adopted for sample selection while semi-structuredquestionnaires were used for data collection. A total of 337 farmers were randomlyselected from four local government areas (Kule, Kwali, Abaji, Gwagwalada and used forthe study. Data were analyzed using descriptive statistics. Results indicated that the majorfactors limiting the farmers from using tractors to work on their farms were high cost oftractor hiring services (64.09% and inadequate sources of hiring points (19.29% resultingin poor access to tractors and its implements. The farmers that hired tractors spent anaverage of N11,543 on land tillage alone hence majority (49.85% of them adopted localimplements like hoes, spades and shovels for land tillage while 10.39% planted withoutland tillage (zero tillage. In addition to land tillage, majority of the farmers (62.31%indicated that, they also hired tractors for the transportation of their farm produce. Privateownership (NGO, Cooperative societies and private individuals were the major (67.95%sources of tractor for hiring while only 13.65% of the farmers accessed government-owned tractors. Based on the findings, the paper recommended that more tractor hiringpoints should be established in the study area and, in addition, the cost of hiring tractorshould be regulated by government in order to encourage farm mechanization.Key words: Cost of tractor hiring, land tillage operation, transportation of farm produce,sources of tractor hiring

  20. Resource Use Efficiency of Turkish Small Scale Dairy Farmers Supported Through Cooperatives in Cukurova Region, Turkey

    OpenAIRE

    Hilal Yilmaz; Tuna Alemdar

    2011-01-01

    Technical efficiencies of cooperative member dairy farmers in Cukurova region were estimated with a stochastic frontier model. Effects of several factors on technical efficiency were analyzed. Farms were grouped based on their efficiency scores. Unit milk costs and gross margins per head cow were calculated for each farm group to give a sense what efficiency means in terms of some farm economic criteria. Concentrate feed and capital costs were found to have statistically significant contribut...

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

    OpenAIRE

    Zekarias Shumeta

    2012-01-01

    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...

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

    Directory of Open Access Journals (Sweden)

    Majory Ongie Meliko

    2011-09-01

    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.

  3. EFFECT OF MICRO FINANCE ON POVERTY REDUCTION OF SMALL SCALE FARMERS OF PAKISTAN

    Directory of Open Access Journals (Sweden)

    Zaheer Ahmad SAEED

    2013-01-01

    Full Text Available This study revealed the impact of micro finance with regard to poverty alleviation, employment generation opportunities, upraise in the standards of living of the small farmers of Pakistan along with the access of such finances and their financial cost. Small farmers often rely on the loans and finance from the formal and informal sources of finance. There is low rate of sustainability in the micro finance sector. These schemes remain for a small time period. Another challenge is that there is a need of replicable and scalable model. There is also a requirement of formalization of informal credit source which count for higher. There is high need of reducing the ambiguities in obtaining the credit from these sources. With respect to agriculture, the proportion of finance should be increase with the proportion to its contribution to the economy. The data for this study has been collected through a selfstructured questionnaire and respondents are small farmers who are availing the micro finance facility for any source; informal, formal or semi – informal. The data collected form 150 respondent from Sahiwal and Multan Region. The data has been analyzed through regression and correlation method with the use of SPSS for checking the relationship and impact of micro finance on the living of poor and employment generation. This paper also concluded that the financial cost of such finances is having significant role on the success of such schemes. The research is a contribution to the financial sector to set their focus according to the quality and quantity of micro credit to the agriculture sector.

  4. Ginger (Zingiber officinale Roscoe Production Efficiency and Constraints Among Small Scale Farmers in Southern Kaduna, Nigeria

    Directory of Open Access Journals (Sweden)

    Titilayo J. Ayodele

    2014-07-01

    Full Text Available Ginger (Zingiber officinale Roscoe is mostly grown in southern Kaduna Sate, the traditional home of ginger in Nigeria. Its production was boosted with the aim of generating internal trade for the people and improved foreign exchange earnings for Nigeria. However, ginger yields in Nigeria are comparatively very low; and this is ascribed to various factors such as poor agronomic practices, unimproved varieties, laborious farming, harvesting and processing operations amongst others. It is against this background that this study carried out to examine the production, constraints and efficiency of production amongst the predominantly poor, rural farmers in the ginger production areas of southern Kaduna, Nigeria. Results showed that, the elasticity of production, farm size (1.21, ginger seed (2.19, fertilizer (0.06 and labor (0.09 are positive and had a significant effect on ginger production in the study area. The estimated coefficient of age (0.004, farming experience (-0.003, education (-0.02 and ginger variety (-0.28 were significant; while that of household size (0.007 was not significant. The fore-most problems affecting ginger production are risk and uncertainties (81.56%, inadequate supply of fertilizer (80.31%, lack of modern farm equipment (76.25%, and lack of credit facilities (74.1%. The technical efficiency of ginger farmers ranged between 0.74 and 1.00; with a mean technical efficiency of 0.82. On the whole, this result suggests that the technical efficiency in ginger production in the area could be further increased by 18% through better use of available resources, given the current state of technology. It can be concluded that specific factors such as age, household size, year of farming experience, and the narrow gene pool (variety of ginger planted, contributed positively to the technical and allocative efficiencies of ginger producers in the region. Ginger farmers could be said to be inefficient in the use of resources and/ or were under-utilizing their resources/input. Evidently, they can still use more resources to increase the output of ginger. Without a doubt, addressing these technical deficiencies and/ or inefficiencies could, in effect, boost ginger production, with the concomitant multiplier effect of increasing the profitability of the entire enterprise and up-liftment of the socio-economic living conditions of these predominantly, low technology base and resource poor farmers of the Southern Kaduna State, Nigeria.

  5. Assessment of Small Scale Farmers’ Skills Regarding Integrated Pest Management (IPM in District Sargodha-Pakistan

    Directory of Open Access Journals (Sweden)

    Ejaz Ashraf

    2012-12-01

    Full Text Available Asurvey study was conducted to assess the knowledge/awareness level in IPM technology among farmers. Fourvillages were randomly selected from Sargodha district fordata collection. Thirteen farmers from each village wereselected randomly and sample size was 52 respondents. Morethan 92% of respondents have no advisory services eitherfrom public or private sector. The findings imply that respondentsneed knowledge for all levels of competence in IPM technology.They need to get high-level of competence for application ofthis technology in the field. In addition, they have littleexposure to long-term training opportunities due to loweducation level for applications of this technology. More than77% of respondents think that government agricultural policiesand no access to information sources regarding integrated pestmanagement at grass-root level are main constraints. Thefindings from correlation and regression analyses indicate thatage and knowledge/awareness level are negatively correlated.It may be concluded that elder respondents have less adaptabilityto new ideas and techniques as compared to young respondents.However, training and information, education, and experienceplay a significant role in enhancing the knowledge/awarenesslevel of respondents in IPM technology.

  6. The impact of mobile phones on knowledge access and transfer of small-scale horticultural farmers in Tanzania

    Directory of Open Access Journals (Sweden)

    Krone, Madlen

    2014-09-01

    Full Text Available Agriculture is the main economic activity in Tanzania and the country´s largest employer, providing livelihood for at least 80 % of the economically active population. Many studies have identified key challenges facing the sector for Africa in general – among these lack of access to knowledge. For agricultural producers, access to knowledge is important for an improved productivity and competitiveness. The fast diffusion of information and communication technologies (ICT such as mobile phones across Africa in the last years has resulted in an improved access and transfer of agricultural knowledge. Studies have shown that rural actors like farmers in remote areas even use mobile phones for their farming business. Based on qualitative interviews in the Mwanza Region in northwestern Tanzania, this study aims to identify and categorise the different types of knowledge which are transferred via mobile phones. Our results show that mobile phones enlarge the ability of farmers to access business-relevant knowledge at an increasing spatial scale. However, the effects of the use depend on the type of knowledge and other factors. The results add to existing studies by deepening the understanding of the benefits of ICT on knowledge access and transfer for the context of rural small-scale framers in Tanzania.

  7. Factors Influencing Potential Acceptance and Adoption of Clean Development Mechanism Projects: Case of Carbon Trade Tree Project among Small Scale Farmers in Njoro District, Kenya

    OpenAIRE

    Oscar I. Ayuya; Job K. Lagat and John M. Mironga

    2011-01-01

    The aim of study was to assess the willingness of small scale farmers to accept and the extent of willingness to adopt carbon trade tree project and by so doing to identify and quantify factors that will influence adoption of carbon trade tree project. The study used multi-stage sampling procedure to select 150 small-scale farmers in Njoro district, Kenya. Both primary and secondary data sources collected using observations and interviews with the help of a semi-structured questionnaire. The ...

  8. 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

  9. Strategies for implementing Climate Smart Agriculture and creating marketable Greenhouse emission reduction credits, for small scale rice farmers in Asia

    Science.gov (United States)

    Ahuja, R.; Kritee, K.; Rudek, J.; Van Sanh, N.; Thu Ha, T.

    2014-12-01

    Industrial agriculture systems, mostly in developed and some emerging economies, are far different from the small holder farms that dot the landscapes in Asia and Africa. At Environmental Defense Fund, along with our partners from non-governmental, corporate, academic and government sectors and farmers, we have worked actively in India and Vietnam for the last four years to better understand how small scale farmers working on rice paddy (and other upland crops) cultivation can best deal with climate change. Some of the questions we have tried to answer are: What types of implementable best practices, both old and new, on small farm systems lend themselves to improved yields, farm incomes, climate resilience and mitigation? Can these practices be replicated everywhere or is the change more landscape and people driven? What are the institutional, cultural, financial and risk-perception related barriers that prevent scaling up of these practices? How do we innovate and overcome these barriers? The research community needs to work more closely together and leverage multiple scientific, economic and policy disciplines to fully answer these questions. In the case of small farm systems, we find that it helps to follow certain steps if the climate-smart (or low carbon) farming programs are to succeed and the greenhouse credits generated are to be marketed: Demographic data collection and plot demarcation Farmer networks and diaries Rigorous baseline determination via surveys Alternative practice determination via consultation with local universities/experts Measurements on representative plots for 3-4 years (including GHG emissions, yields, inputs, economic and environmental savings) to help calibrate biogeochemical models and/or calculate regional emission factors. Propagation of alternative practices across the landscape via local NGOs/governments Recording of parameters necessary to extrapolate representative plot GHG emission reductions to all farmers in a given landscape under several existing and new carbon offset methodologies. In this presentation, we will discuss our initial encouraging results on the basis of which our wider team now seeks to identify and recommend policies that the local governments to be able to scale up climate smart agriculture to larger jurisdictional levels.

  10. Ixodid ticks on indigenous goats owned by small-scale farmers in four communal grazing areas in South Africa

    Directory of Open Access Journals (Sweden)

    B.A.J. du Plessis

    2012-07-01

    Full Text Available Indigenous goats belonging to small-scale farmers in 4 communal grazing areas in South Africa were sampled for ixodid ticks during the period September 1991 to May 1993. Three of these areas were in the North West Province (Rietgat, Madinyane and Bethany, and one in Mpumalanga Province (Geluk. No tick control was practised unless requested by the owners. Seven ixodid tick species, of which the majority were immature ticks, were collected from the goats in North West Province. Amblyomma hebraeum was the most numerous of these, followed by Rhipicephalus evertsi evertsi and Rhipicephalus appendiculatus. Substantially more ticks were collected from goats at Rietgat than at the Madinyane and Bethany grazing areas. Five tick species were collected at Geluk and R. evertsi evertsi comprised more than 95 % of the total population. At Rietgat and Geluk A. hebraeum nymphs were present on goats throughout the year, while most R appendiculatus nymphs were collected during September and October 1991 and most adults during January and February 1992. At both Rietgat and Geluk most immature R. evertsi evertsi were collected from spring to late summer, while adults were present throughout the year.

  11. Factors Influencing Potential Acceptance and Adoption of Clean Development Mechanism Projects: Case of Carbon Trade Tree Project among Small Scale Farmers in Njoro District, Kenya

    Directory of Open Access Journals (Sweden)

    Oscar I. Ayuya

    2011-04-01

    Full Text Available The aim of study was to assess the willingness of small scale farmers to accept and the extent of willingness to adopt carbon trade tree project and by so doing to identify and quantify factors that will influence adoption of carbon trade tree project. The study used multi-stage sampling procedure to select 150 small-scale farmers in Njoro district, Kenya. Both primary and secondary data sources collected using observations and interviews with the help of a semi-structured questionnaire. The double hurdle model was used identify the factors that influence the willingness to accept and the extent the farmers are willing to adopt the carbon tree trade project. Findings of the double hurdle model indicate that gender, household size, farm debt, attitude towards risk, farm size,land tenure, availability of voluntary CDM and perception of the technology were found to influence the willingness to accept the project. Further, age, extension contacts, attitude towards risk, land tenure and perception towards the technology influenced on the extent the farmer is willing to adopt. The study therefore, recommends policy interventions of improved training offarmers and extension officers on agroenvironmental programmes, formation of agro-environmental self-help groups by farmers and creation of strategies that would improve socio-economic conditions of smallholder farmers in Kenya.

  12. 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)

    A J, Jordaan.

    Full Text Available 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 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.

  13. Exploring the role of sugarcane in small-scale farmers' livelihoods in the Noodsberg area, KwaZulu-Natal, South Africa

    Scientific Electronic Library Online (English)

    J. J, Cockburn; H. C, Coetzee; J, Van den Berg; D. E, Conlong; J, Witthöft.

    Full Text Available Participatory, mixed-methods research was conducted to study the role of sugarcane in small-scale sugarcane farmers' livelihoods in the Noodsberg area, KwaZulu-Natal. Thirty-five farmers were visited at their homes and data was collected through semi-structured interviews, participatory sketch mappi [...] ng, matrix scoring activities and informal field-based discussions. Results indicated that sugarcane was a key livelihood resource providing employment and income, and it generated more income than any other single agricultural enterprise. It was considered the most important crop in most households, even though it was grown within a diverse agricultural system including maize, beans, taro (amadumbe) and potatoes. Considering the important role of sugarcane as a cash crop in farmers' livelihoods, further development of land to sugarcane in the Noodsberg area will continue to reduce poverty and improve the livelihoods of farmers.

  14. Ixodid ticks on cattle belonging to small-scale farmers at 4 communal grazing areas in South Africa

    Directory of Open Access Journals (Sweden)

    N.R. Bryson

    2012-07-01

    Full Text Available Ixodid ticks were collected during the period September 1991 to August 1993 from cattle belonging to small-scale farmers utilising 4 communal grazing areas. Three of these were in North West Province and 1 in Mpumalanga province, South Africa. Ten tick species were collected in North West Province and 7 in Mpumalanga. The adults of Amblyomma hebraeum, Rhipicephalus appendiculatus and Rhipicephalus evertsi evertsi were most numerous in North West Province, while in Mpumalanga Boophilus decoloratus comprised more than 75% of the total population. Amblyomma hebraeum was present on all grazing areas, and heavy infestations of adults occurred during the period October to May on 1 of these. Few B. decoloratus were collected in North West Province, chiefly because the sampling method was inadequate, and most of these were present during early summer (October to December and late summer and autumn (March to May. The initially low population of B. decoloratus in Mpumalanga increased substantially towards the conclusion of the survey, probably because of the cessation of dipping. Boophilus microplus was present in small numbers on 2 grazing areas in the North West Province. Adult Hyalomma marginatum rufipes reached peak numbers from December to February and Hyalomma truncatum from February to April in the North West Province. Only H. marginatum rufipes was collected in Mpumalanga. Rhipicephalus appendiculatus was present on all the grazing areas, with most adults present from December to April. Most adult Rhipicephalus evertsi evertsi were collected from September to April and Rhipicephalus simus was present during the period October-April.

  15. Understanding the dynamics of multi-stakeholder innovation systems and the opportunities for joint learning by small scale farmers

    Scientific Electronic Library Online (English)

    J. B., Stevens; B., Letty.

    2014-12-01

    Full Text Available Through a European Union funded project called JOLISAA (Joint Learning in Innovation Systems in African Agriculture), the nature of smallholder oriented innovation systems have been explored in terms of partnerships, triggers that have given rise to them and the nature of the innovations themselves. [...] The main objective was to analyse a broad diversity of multi-stakeholder agricultural innovation processes involving smallholders. The analysis of 11 cases documented comprises innovation bundles composed of technical, organisational and institutional innovations. The eleven cases documented showed that six exhibited nontechnical innovation processes frequently related to market access as well as to inputs and services. Triggers that drive smallholders and other stakeholders to initiate innovation processes include environment stress, introduction of new technologies, identification of market change as well as policy or regulatory changes. The cases that have been documented show a variation of stakeholders responsible for initiating the process. In some cases it was smallholders approaching other stakeholders for assistance with addressing a challenge, while in other cases it was researchers or extensionists who undertook to develop an innovation to address a challenge that they had encountered through their interaction with smallholders. All documented cases have involved the contribution of ideas, knowledge and skills by at least three different types of stakeholders and the role of local knowledge has been acknowledge through the study. Out of the eleven cases three cases have been selected for a collaborative case assessment which strives to assess further key issues such as actual roles and contributions of various role-players, the dynamics of the innovation process and outcome. Several opportunities arise for joint learning with small scale farmers.

  16. Pesticide knowledge, practice and attitude and how it affects the health of small-scale farmers in Uganda : a cross-sectional study

    DEFF Research Database (Denmark)

    Oesterlund, Anna H; Thomsen, Jane F

    2014-01-01

    BACKGROUND: Over the past years there has been an increase in the use of pesticides in developing countries. This study describes pesticide use among small-scale farmers in Uganda and analyses predictors of pesticide poisoning (intoxication) symptoms. METHOD: A cross-sectional study was conducted using a standardized questionnaire. Some 317 small-scale farmers in two districts in Uganda were interviewed about pesticide use, knowledge and attitude, symptoms of intoxication, personal protective equipment (PPE) and hygiene. The risk of reporting symptoms was analysed using logistic regression analysis. RESULTS: The most frequently used pesticides belonged to WHO class II. The farmers had poor knowledge about pesticide toxicity, and the majority did not use appropriate PPE nor good hygiene when handling pesticides. There was no significant association between the number of times of spraying with pesticides and self-reported symptoms of pesticide poisoning. The only significant association was between blowing and sucking the nozzle of the knapsack sprayer and self-reported symptoms of pesticide intoxication (OR: 2.13. 95% CI: 1.09 - 4.18). CONCLUSION: Unlike the practice in several other developing countries, small-scale farmers in Uganda do not use the most hazardous pesticides (WHO class 1a and 1b). However use of WHO class II pesticides and those of lower toxicity is seen in combination with inadequate knowledge and practice among the farmers. This poses a danger of acute intoxications, chronic health problems and environmental pollution. Training of farmers in Integrated Pest Management (IPM) methods, use of proper hygiene and personal protective equipment when handling pesticides should be promoted.

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

    Science.gov (United States)

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

    2009-01-01

    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…

  18. A study of knowledge, attitudes and practices relating to brucellosis among small-scale dairy farmers in an urban and peri-urban area of Tajikistan.

    Science.gov (United States)

    Lindahl, Elisabeth; Sattorov, Nosirjon; Boqvist, Sofia; Magnusson, Ulf

    2015-01-01

    Improvement of knowledge, attitudes and practices among urban livestock farmers could have a significant impact on the reduction of many zoonotic infections in urban farming. This study aimed to describe and evaluate weak areas in knowledge, attitudes and practices with regards to brucellosis among urban and peri-urban small-scale dairy farmers in a low income country to generate information essential for control programmes and public health interventions. The cross-sectional study was conducted during six weeks in 2011. The study subjects were small-scale dairy farmers living in the urban and peri-urban area of the capital Dushanbe in Tajikistan. In total, 441 farmers were interviewed using a questionnaire with questions about demographic characteristics, knowledge, attitudes and practices relating to brucellosis. Descriptive statistics were used and a logistic regression model applied to evaluate potential predictors to knowledge about brucellosis. The majority (85%) of the farmers had never heard of brucellosis. Low educational level was found to be associated with low awareness of brucellosis (P = animal health issues with family members or friends were less likely to have heard of brucellosis compared to those who often talked to veterinarians (P = 0.03). Sixty three per cent of the participants wanted more information about brucellosis. Seventeen per cent sold unpasteurized dairy products on a regular basis direct to consumers. Almost 30% of the households consumed unpasteurized dairy products on regular basis. A majority of the respondents did not use any protection when handling cows having an abortion or when dealing with aborted materials. Poor knowledge, high-risk behaviours and a willingness to learn more strengthens the logic for including health education as part of control programmes. PMID:25668783

  19. BT cotton in South Africa : adoption and the impact on farm incomes amongst small-scale and large-scale farmers

    OpenAIRE

    Gouse, Marnus; Kirsten, Johann F.; Jenkins, L.; Gouse, Marthinus

    2003-01-01

    South Africa is one of few developing countries, and the only one in Africa that has adopted genetically modified crops for commercial production. The very impressive adoption rate of insect-resistant cotton in South Africa can be attributed to different benefits enjoyed by adopters. This article focuses on the reasons and effects of Bt cotton adoption by large-scale and small-scale cotton farmers in South Africa and considers the impact of the adoption on yields, cost and profit. In addition...

  20. Interactive Design of Farm Conversion : linking Agricultural Research and Farmer Learning for Sustainable Small Scale Horticulture Production in Colombia

    OpenAIRE

    Lee, R.A.

    2002-01-01

    Key words: interactive conversion design / vegetable production / small farms / sustainable farming / Colombia / learning processes / facilitation / agricultural research methodsEconomic and ecological pressure on small farmer production in Colombia has increased since the globalisation of trade in the early 1990s. Although the climate allows for year-round production, the farmers live precariously due to a high dependence on external inputs, poor access to different sources of information on...

  1. Differences of small-scale farmers and the related short agri-food value chains An empirical evidence from Hungary

    OpenAIRE

    Benedek, Zso?fia; Ferto?, Imre; Bara?th, Lajos; To?th, Jo?zsef

    2014-01-01

    Recently, short food supply chains have been thoroughly studied in some countries; however, data are sparse from others. In Hungary, the local food movement has been developing very fast and an outburst in the number of farmers markets has happened, due to the changes of the legal environment. The paper addresses the question whether farmers selling at various short food supply chains are different based on their socio-demographic, farm- and production-related characteristics, expectations an...

  2. CONTRACT FARMING AND ITS IMPACT ON INCOME AND LIVELIHOODS FOR SMALL-SCALE FARMERS: CASE STUDY IN VIETNAM

    Directory of Open Access Journals (Sweden)

    Nham Phong Tuan

    2012-01-01

    Full Text Available Contract farming has been expected as one of the measures to facilitate participation of farmers in the production of agriculture commercially, adding more values to agricultural produces. Mixed evidence in Vietnam however, has been shown on the well-known ad-vantage of the contract farming to small farmers such as reduce the cost to access to market, accessing credit, obtaining information on market opportunities or new technologies, pur-chasing certain inputs and accessing product markets and reducing price fluctuations. The purpose of this study was to analyse the impact of contract farming to farmers and to deter-mine policies to facilitate farmer entry into beneficial contractual relationships. In addition to the literature review, one intensive case study of contract farming practices with commodity was conducted. The results from the study have direct relevance to work of agencies and organizations working to promote the welfare of small holding farmers, either through prac-tical field support or through policy advocacy.

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

    Directory of Open Access Journals (Sweden)

    P.J. Masika

    2012-07-01

    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.

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

    OpenAIRE

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

    2012-01-01

    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 w...

  5. 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)

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

    2013-07-01

    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.

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

    International Nuclear Information System (INIS)

    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 prodased use of manure resources for crop production. (author)

  7. Social Impact Assessment of Crude Oil Pollution on Small Scale Farmers in Oil Producing Communities of the Central Agricultural Zone of Delta State, Nigeria

    Directory of Open Access Journals (Sweden)

    Ofuoku, A. O. U.

    2014-03-01

    Full Text Available The study assessed the social impact of oil production on small holder farmers in oil-producing communities of the Central zone of Delta State, Nigeria. Data were collected from 120 respondents by the use of questionnaires. Soil erosion (96.6%, noise pollution (98.3%, bush burning (93.3%, land degradation/pollution (87.5%, water pollution (80.3%, air pollution (62.5%, massive deforestation (62.5% and acid rain (52.5% were seen as the major environmental problems experienced in the study area. The respondents reported that oil pollution impacted negatively on their income (83.3%, agricultural production (98.3% and land availability (85.8%. None of the socio-economic characteristics of the respondents such as age, gender, Educational level, religion, marital status, type of farming, family size, Farming experience, farm size, income, housing, tenure, membership of organization, land tenure and source of labour were found to determine the social impact of oil pollution on small-scale farmers. Recommendations given dwelt on making the environment conducive for the communities, agricultural activities and it sustenance for future generations.

  8. Induced innovation and productivity-enhancing, resource-conserving technologies in Central America : The supply of soil conservation practices and small-scale farmers? adoption in Guatemala and El Salvador

    OpenAIRE

    Zurek, Monika Barbara

    2002-01-01

    Aim of the study is to investigate the adoption behavior of small-scale farmers in Central America with respect to soil conservation technologies that combine soil protection with productivity enhancing aspects. In two case studies, carried out in the Polochic Valley in Guatemala and the county of Nueva Concepción, El Salvador, farmers were surveyed with regard to soil erosion problems on their farm, the use of soil conservation practices and a number of household characteristics. Particular ...

  9. 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)

    Stefan Schmidt

    2013-09-01

    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.

  10. Perceptions of Brazilian small-scale farmers about genetically modified crops / As percepções de pequenos agricultores brasileiros sobre os cultivos geneticamente modificados

    Scientific Electronic Library Online (English)

    Carla, Almeida; Luisa, Massarani; Ildeu de Castro, Moreira.

    2015-03-01

    Full Text Available O objetivo deste artigo é investigar as percepções de pequenos agricultores brasileiros acerca dos cultivos geneticamente modificados com base em 15 grupos focais, envolvendo 111 indivíduos. A análise do corpus revela percepções heterogêneas em relação a essas culturas, moldadas por diversos fatores [...] , incluindo as perspectivas econômicas e preocupações com o impacto sobre a saúde e o meio ambiente. Há muitas dúvidas sobre esses efeitos entre os agricultores, que estão interessados ??em receber informação neutra sobre o tema. Essas incertezas os afeta mais como consumidores, visto que preferem comer alimentos não transgênicos, do que como produtores, quando privilegiam outros aspectos, especialmente econômicos, ao decidir o que cultivar. Embora a maioria acredite que deva ter voz em tomadas de decisão referentes a questões agrícolas, poucos têm feito esforços nesse sentido. Abstract in spanish El objetivo de este artículo es investigar las percepciones de pequeños agricultores brasileños acerca de los cultivos transgénicos, con base en 15 grupos focales, involucrando a 111 individuos. El análisis del corpus revela percepciones heterogéneas con respecto a estos cultivos, debido a muchos fa [...] ctores, incluyendo las perspectivas económicas y preocupaciones con el impacto sobre la salud y el medio ambiente. Los agricultores expresan deseo de recibir información imparcial sobre el tema, sobre el cual tienen muchas dudas. Las incertidumbres los afecta más como consumidores, visto que afirman preferir comer alimentos no transgénicos, que como productores, momento en que privilegian otros aspectos, especialmente económicos, al decidir lo que cultivar. Aunque la mayoría acredite que deba tener voz en las tomadas de decisión referentes a temas agrícolas, pocos han hecho esfuerzos en esta dirección. Abstract in english The aim of this paper is to investigate the perceptions of small-scale farmers in Brazil towards genetically modified (GM) crops based on a sample of 15 focus groups involving 111 individuals. The analysis of the corpus shows heterogeneous perceptions regarding these crops, shaped by diverse factors [...] , including economic prospects and concerns with the impact on health and the environment. There are many misgivings about these effects among the farmers, who are keen to receive unbiased information on the topic. These uncertainties affect them more as consumers, as most would prefer eating GM-free food, than as producers, as they consider other aspects, especially economic feasibility, when deciding what to grow. Although most farmers believe they should have a voice in decision-making on agricultural issues, few have made concerted efforts to be heard.

  11. Small-Scale Farmers Land Use and Socioeconomic Situation in the Mount Elgon District in Northwestern Kenya : A Minor Field Study - Combined Field Mapping and Interview

    OpenAIRE

    Kaati, Patrik

    2011-01-01

    This Minor Field Study was carried out during November and December in 2011 in the Mount Elgon District in Western Kenya. The objective was to examine nine small-scale farming household´s land use and socioeconomic situation when they have joined a non-governmental organization (NGO) project, which specifically targets small-scale farming households to improve land use system and socioeconomic situation by the extension of soil and water conservation measures. The survey has worked along thr...

  12. Analysis of the effects of Zimbabwean white farmers on small scale farming in Nigeria Análisis de los efectos de la presencia de agricultores blancos de Zimbabwe en la agricultura a pequeña escala en Nigeria

    Directory of Open Access Journals (Sweden)

    Matthew Olaniyi Adewumi

    2013-05-01

    Full Text Available Many observers believe that the on-going liberalization of the world will have dramatic negative effects on small farmers in both developed and developing countries. This study aims to capture the effects of the presence of foreign migrant farmers on small scale farm­ing systems, which are prevalent in Nigeria. The Agricultural Development Project Zone D in which the white farmers settled in the state of Kwara, was used as a case study. Primary data were collected from white farmers as well as from local farmers regarding their situ­ation before and after the arrival of white farmers. Descriptive statistics and analysis of the farm budget were used in evaluating the data. The majority of local farmers (98.63% transitioned towards sole cropping since the arrival of white farmers in the area. There were significant increases in seed rate, fertilizer and other chemicals, as well as labor inputs per farmer in the area when compared to the situation that was prevalent before the white farmers settled there. Their average farm size, distances between their houses and farms and tractor use reduced significantly, while output per farm size increased considerably since the arrival of white farmers in the area. In order to provide sustainability of the posi­tive development, there is the need to seek a policy option that will calm local farmers who once in a while exhibit signs of dissatisfaction for the way in which white farmers came to settle on their land. These could be achieved through the use of the participatory approach to agricultural development in the area. This approach could also be relevant in other re­gions of the world with similar situations. Muchos observadores consideran que la creciente liberalización del mundo tendrá efectos negativos en la agricultura en pequeña escala tanto en los países desarrollados como en aquéllos en vías de desarrollo. Este estudio pretende capturar los efectos de la presencia de agricultores migrantes extranjeros en los sistemas de agricultura a pequeña escala prevale­cientes en Nigeria. El Proyecto de Desarrollo de la Agricultura Zona D, en el cual los agricul­tores blancos se establecieron en el estado de Kwara, fue utilizado como caso de estudio. La información primaria fue obtenida de agricultores blancos así como de agricultores locales considerando su situación pre y post la llegada de los agricultores blancos. Las estadísticas descriptivas y el análisis del presupuesto de cada parcela fueron utilizados para evaluar la información. La mayoría de los agricultores locales (98.63% han transitado hacia el monocultivo desde la llegada de los agricultores blancos a la región. Se ha observado un incremento significativo en la tasa de uso de semillas, el uso de fertilizantes y otros agro­químicos, así como en el trabajo humano por agricultor en el área en comparación con la situación prevaleciente antes de la llegada de los agricultores blancos. El tamaño promedio de sus tierras, la distancia de estas con respecto de sus hogares y uso de tractores se ha reducido de forma importante, mientras que la producción por agricultor se ha incrementa­do. La búsqueda de políticas que tranquilicen a los agricultores locales quienes en ocasio­nes manifiestan su insatisfacción por la forma en que los agricultores blancos han llegado a establecerse en estas tierras resulta imperativa. Esto permitirá lograr un desarrollo positivo y sustentable. Estas políticas pueden ser desarrolladas a través de un enfoque participativo en el desarrollo de la agricultura en el área. Este enfoque también podría resultar relevante en otras regiones del mundo que presentan situaciones similares.

  13. Effect of Small-scale Irrigation on the Farm Households’ Income of Rural Farmers: The Case of Girawa District, East Hararghe, Oromia, Ethiopia

    Directory of Open Access Journals (Sweden)

    Beyan A

    2014-03-01

    Full Text Available Irrigation is one means by which agricultural production can be increased to meet the growing food demands in the world. This study evaluated the effect of small-scale irrigation on farm household income in production. The specific objective of this study is to identify the factors in-fluencing participation in small-scale irrigation and provides bases for policy makers in Girawa district, Eastern Hararghe zone, Oromia, Ethiopia. Both primary and secondary data were col-lected for the study. Primary data were collected from 200 sample respondents drawn from both participant and non-participant households. Preliminary statistics and econometric models were employed for data analysis. The logistic regression estimation of factors affecting participation re-vealed that age of household head, non-farm income, livestock size, size of cultivated land, dis-tance between plot and irrigation scheme, means of transportation and participation of household heads in social organization significantly affected the participation decision of households in irri-gation farming. Results showed that participation in irrigation has a significant, positive effect on farm households’ income. Therefore, policy makers should give due emphasis to the aforemen-tioned variables to increase participation in irrigation farming and improve the livelihood of rural households.

  14. Social Impact Assessment of Crude Oil Pollution on Small Scale Farmers in Oil Producing Communities of the Central Agricultural Zone of Delta State, Nigeria

    OpenAIRE

    Ofuoku, A. O. U.; Emuh, F. N.; Ezeonu, O.

    2014-01-01

    The study assessed the social impact of oil production on small holder farmers in oil-producing communities of the Central zone of Delta State, Nigeria. Data were collected from 120 respondents by the use of questionnaires. Soil erosion (96.6%), noise pollution (98.3%), bush burning (93.3%), land degradation/pollution (87.5%), water pollution (80.3%), air pollution (62.5%), massive deforestation (62.5%) and acid rain (52.5%) were seen as the major environmental problems experienced in the stu...

  15. Healthy sand : a farmers initiative on soil protection and ecosystem service management

    Science.gov (United States)

    Smit, Annemieke; Verzandvoort, Simone; Kuikman, Peter; Stuka, Jason; Morari, Francesco; Rienks, Willem; Stokkers, Jan; Hesselink, Bertus; Lever, Henk

    2015-04-01

    In a small region in the Netherlands a group of dairy farmers (cooperated in a foundation HOE Duurzaam) cooperates with the drinking water company and together aim for a more healthy soil. They farm a sandy soil, which is in most of the parcels low in organic matter. The local farmers perceive loss of soil fertility and blame loss of soil organic matter for that. All farmers expect that increasing the soil organic matter content will retain more nitrates in the soil, leading to a reduction in nitrate leaching and a higher nutrient availability for the crops, forage and grass and probably low urgency for grassland renewal. The drinking water company in the area also has high expectations that a higher SOM content does relate to higher quality of the (drinking) water and lower costs to clean and filter the water to meet drinking water quality requirements. Most farmers in the area face suboptimal moisture conditions and thrive for increasing the soil organic matter content and improving the soil structure as key factors to relieve, soil moisture problems both in dry (drought) and wet (flooding) periods. A better water holding capacity of the soil provides benefits for the regional water board as this reduces leaching and run-off. The case study, which is part of the Recare-project, at first glance deals with soil management and technology to improve soil quality. However, the casus in fact deals with social innovation. The real challenge to this group of neighbours, farmers within a small region, and to science is how to combine knowledge and experience on soil management for increasing the content of soil organic matter and how to recognize the ecosystem services that are provided by the adapted and more 'healthy' soils. And also how to formalize relations between costs and benefits of measures taken in the field and how these could be financially rewarded from an agreed and acceptable financial awarding scheme based on payments for securing soil carbon stocks and increasing carbon fluxes to soils. In the presentation we want to discuss • what choices in optimal farming practices and strategy for Dutch farmers help to increase soil organic matter content in the soil in the next 5-10 years? • What role can the foundation play in organising the practices and the payment for extra activities, collecting results and present them to benefitting stakeholders? • What valuation of ecosystem service and which payment scheme would satisfy the needs of both farmers as recipient and water board and regional government as beneficiaries and financing body for ecosystem service provided for.

  16. Small scale optics

    CERN Document Server

    Yupapin, Preecha

    2013-01-01

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

  17. Small scale and microdosimetry

    International Nuclear Information System (INIS)

    This lecture, after explaining the limitations of the MIRD (Medical Internal Radiation Dose) method, describes the small scale dosimetry for electrons and photons as well as the basis for the microdosimetry. The techniques for doses calculations are outlined

  18. Small scale windmill

    Science.gov (United States)

    Myers, Robert; Vickers, Mike; Kim, Hyeoungwoo; Priya, Shashank

    2007-01-01

    In this letter the authors report experimental results on an optimized small scale piezoelectric windmill, which can solve the problems associated with autonomous sensor networks in outdoor, remote or inaccessible locations. The whole structure of the windmill is made of plastic, and it utilizes 18 piezoelectric bimorphs which makes this design extremely cost effective. The windmill was tested at average wind speed of 10miles/h and it provided 5mW continuous power. The threshold wind speed for the windmill was found to be of the order of 5.4miles/h. Further, the authors present analysis on two other windmill structures which illustrate the design parameters required for small scale windmill.

  19. Contract farming and its impact on income and livelihoods for small-scale farmers: Case study in Vietnam Kontraktacja i jej wp?yw na dochód i utrzymanie rolników produkuj?cych na ma?? skal?

    Directory of Open Access Journals (Sweden)

    Nham Phong Tuan

    2012-12-01

    Full Text Available Contract farming has been expected as one of the measures to facilitate participation of farmers in the production of agriculture commercially, adding more values to agricultural produces. Mixed evidence in Vietnam however, has been shown on the well-known ad-vantage of the contract farming to small farmers such as reduce the cost to access to market, accessing credit, obtaining information on market opportunities or new technologies, pur-chasing certain inputs and accessing product markets and reducing price fluctuations. The purpose of this study was to analyse the impact of contract farming to farmers and to deter-mine policies to facilitate farmer entry into beneficial contractual relationships. In addition to the literature review, one intensive case study of contract farming practices with commodity was conducted. The results from the study have direct relevance to work of agencies and organizations working to promote the welfare of small holding farmers, either through prac-tical field support or through policy advocacy.

  20. Sustainable Small-Scale Agriculture in Semi-Arid Environments

    OpenAIRE

    Scott Ingram; Margaret Nelson; Spielmann, Katherine A.; Peeples, Matthew A.

    2011-01-01

    For at least the past 8000 years, small-scale farmers in semi-arid environments have had to mitigate shortfalls in crop production due to variation in precipitation and stream flow. To reduce their vulnerability to a shortfall in their food supply, small-scale farmers developed short-term strategies, including storage and community-scale sharing, to mitigate inter-annual variation in crop production, and long-term strategies, such as migration, to mitigate the effects of sustained droughts. W...

  1. 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)

    OpenAIRE

    Stefan Schmidt; Joyce Thamaga-Chitja; Fezile Mdluli

    2013-01-01

    During October, November and December 2011 (when highest sales of Agri-Hub fresh produce are observed), irrigation water, compost, lettuce and spinach sampled from four different farmer cooperatives supplying the local Agri-Hub in uMbumbulu (KwaZulu-Natal, South Africa) were analyzed monthly for the presence of total and fecal coliforms and Escherichia coli using the most probable number (MPN) technique. The pH values for all irrigation water samples analyzed were within the acceptable range ...

  2. EFFECTS OF THE INTRODUCTION OF DIRECT SEEDED MAIZE PRODUCTION UNDER SMALL SCALE FARMERS CONDITIONS IN UNAÍ, MG (BRAZILIAN CERRADO EFEITOS DA INTRODUÇÃO DO SISTEMA DE PLANTIO DIRETO DE MILHO POR AGRICULTORES FAMILIARES DO MUNICÍPIO DE UNAÍ, MG (CERRADO BRASILEIRO

    Directory of Open Access Journals (Sweden)

    José Luiz Fernandes Zoby

    2009-01-01

    Full Text Available

    This paper evaluates the effects of the introduction of no tillage systems (SPD in rainfed maize grain production, by smallholders, under Cerrado conditions, in the region of Unaí, Minas Gerais State, Brazil. The main constraints faced by farmers to produce are related to soil fertility management, difficulties in assessing tractors for preparing their land, and high levels of weed infestation. SPD was tested jointly with farmers trying to decrease these problems impacts. It showed promising results to stabilize, technically and economically, maize production. SPD solved completely the tractors dependency and contributed to decrease labour requirements for weed control. The production levels attained led to a better valorisation of the most scarce production factors, such as family labour and land. It was also evidenced the need to conduct more studies on the use of cover crops in those production systems.

     

    Key-words: Family farming; conservation agriculture; no-tillage.

  1. Management of broadleaved weeds in small-scale in an on-farm perspective

    International Nuclear Information System (INIS)

    An on-farm trial was conducted at eight different sites in Rongai and Njoro areas of Nakuru district and only six of the sites were finally harvested. The study was mainly to evaluate different weed control methods to offer a variety of recommendations for small scale wheat farmers. Of the treatments tested Buctril Mc out performed all the treatments except for Ariane. Cultural methods of control seemed to be inferior to almost all the chemical control. (author)

  2. IAPSA 2 small-scale system specification

    Science.gov (United States)

    Cohen, Gerald C.; Torkelson, Thomas C.

    1990-01-01

    The details of a hardware implementation of a representative small scale flight critical system is described using Advanced Information Processing System (AIPS) building block components and simulated sensor/actuator interfaces. The system was used to study application performance and reliability issues during both normal and faulted operation.

  3. 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...

  4. Degradation mechanisms of small scale piping systems

    International Nuclear Information System (INIS)

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

  5. SMALL SCALE INDUSTRIES BENEFICIAL FOR GROWTH

    Directory of Open Access Journals (Sweden)

    Neetu Khullar

    2015-03-01

    Full Text Available Industrial growth is important for any economy whether developing or under developed. It has more significance for a developing economy like India which has abundant labour but is short of capital. Small scale industries provide an excellent opportunity of growth to the unskilled labour. This research tells us about the significant and dynamic role Small Scale Industries can have in developing economy like India. They not only provide huge employment opportunities at comparatively lower capital cost than big industries. These small industries help in the in the Industrialization of rural and backward areas reducing regional imbalances leading to equitable distribution of income and wealth. These industries are basically capital deficient, growth can be achieved in these economies by utilizing the labour power. After agriculture its these industries where maximum number people are engaged and most of the developing economies are agriculture based.

  6. Small-scale tearing mode in tokamaks

    International Nuclear Information System (INIS)

    Considerations are given on the possible effect of small-scale tearing mode with m >> 1 on the plasma electron thermal conductivity in a tokamak. The estimate of the electron thermal conductivity coefficient is obtained. Calculation results are compared with experimental data. The calculated dependence of radial distribution of electron temperature is shown to vary weakly with the tn(m2/m1) alteration everywhere, except for the vicinity of point r approximately 0

  7. Small Scale Foundries in Ghana: The challenges

    OpenAIRE

    Emmanuel GIKUNOO; Anthony ANDREWS

    2011-01-01

    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, individu...

  8. Small-Scale Tomato Cultivators’ Perception on Pesticides Usage and Practices in Buea Cameroon

    Directory of Open Access Journals (Sweden)

    Tinyami Erick Tandi

    2014-12-01

    Full Text Available It has been shown that farmers with limited knowledge of the use and safe handling of pesticides may suffer exposure which results in adverse health effects. In Buea, Cameroon, small-scale tomato farmers commonly use pesticides for pest control. Information was obtained from these tomato farmers to determine the extent and types of their pesticide use, their knowledge of pesticide use and effectiveness, and their perception of potential harm resulting from pesticide use. A standardized questionnaire, interviews, field observations and an analytical ranking game were used to describe the pesticide use of 93 tomato farmers. Many farmers (47.6% used pyrethiod and organophosphorus insecticides and identified these chemicals as the most effective in pesticide control; these are WHO Class II pesticides which are the most hazardous to humans. Most farmers (83.8% used knapsack sprayers to apply pesticides, with 76.3% using no or partial personal protective equipment (PPE. It was notable that 55.5% of farmers expressed no concern regarding the wind direction (pesticide drift during spraying. The results showed a significant association between the method of pesticides application and farm size (P < 0.001. Most farmers (85.0% reported at least one symptom of acute pesticide poisoning following spraying. This study revealed that the tomato farmers have a high exposure to pesticides secondary to inadequate knowledge of the safe and judicious use of pesticides. Strategies that provide training on the appropriate use of pesticides, how to reduce exposure to and health risks of pesticides and alternative options of pest management and control are required. The study also raised concerns that further control of the sale and distribution of pesticides may be indicated.

  9. Small-scale rural bakery; Maaseudun pienleipomo

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-12-31

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

  10. Philippines: Small-scale renewable energy update

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-01

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

  11. Adopting small-scale production of electricity

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-07-01

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

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

    International Nuclear Information System (INIS)

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

  13. Quality management in the Pangasius export supply chain in Vietnam : the case of small-scale Pangasius farming in the Mekong River Delta

    OpenAIRE

    Khoi, Le Nguyen Doan,

    2011-01-01

    The thesis focuses on three areas: quality control at farm level, quality assurance at chain level, and the business relationships at farm level. The objective of this thesis is to explore the major challenges for the present quality management system to assure safety and quality standards in the export supply chain of small-scale fish farming in Vietnam. The findings show that problems of small-scale farmers involved in export supply chain can be dealt with through developing business re...

  14. Small-scale clumps of dark matter

    International Nuclear Information System (INIS)

    Small-scale clumps of dark matter are gravitationally bounded structures that have masses comparable to or lower than stellar masses and consist of noninteracting or weakly interacting dark matter particles. In this paper, the current knowledge about the formation and evolution of such structures is reviewed, various types of spectra of primordial cosmological perturbations are considered, and various dark matter models are discussed. Depending on the particular spectrum type, dark matter clumps may differ considerably in their formation processes and ultimate characteristics. The role of clumps in experiments on indirect detection of dark matter particles via their annihilation products is discussed. A number of astrophysical problems and phenomena that are related to dark matter clumps are examined. (reviews of topical problems)

  15. Small scale structure formation in chameleon cosmology

    International Nuclear Information System (INIS)

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

  16. Small-scale clumps of dark matter

    CERN Document Server

    Berezinsky, V S; Eroshenko, Yu N

    2014-01-01

    Small-scale clumps of dark matter are gravitationally bounded structures that have masses comparable to or lower than stellar masses and consist of noninteracting or weakly interacting dark matter particles. In this paper, the current knowledge about the formation and evolution of such structures is reviewed, various types of spectra of primordial cosmological perturbations are considered, and various dark matter models are discussed. Depending on the particular spectrum type, dark matter clumps may differ considerably in their formation processes and ultimate characteristics. The role of clumps in experiments on indirect detection of dark matter particles via their annihilation products is discussed. A number of astrophysical problems and phenomena that are related to dark matter clumps are examined.

  17. Small-Scale Features in Pulsating Aurora

    Science.gov (United States)

    Jones, Sarah; Jaynes, Allison N.; Knudsen, David J.; Trondsen, Trond; Lessard, Marc

    2011-01-01

    A field study was conducted from March 12-16, 2002 using a narrow-field intensified CCD camera installed at Churchill, Manitoba. The camera was oriented along the local magnetic zenith where small-scale black auroral forms are often visible. This analysis focuses on such forms occurring within a region of pulsating aurora. The observations show black forms with irregular shape and nonuniform drift with respect to the relatively stationary pulsating patches. The pulsating patches occur within a diffuse auroral background as a modulation of the auroral brightness in a localized region. The images analyzed show a decrease in the brightness of the diffuse background in the region of the pulsating patch at the beginning of the offphase of the modulation. Throughout the off phase the brightness of the diffuse aurora gradually increases back to the average intensity. The time constant for this increase is measured as the first step toward determining the physical process.

  18. Small-scale nonlinear dynamics of K-mouflage theories

    Science.gov (United States)

    Brax, Philippe; Valageas, Patrick

    2014-12-01

    We investigate the small-scale static configurations of K-mouflage models defined by a general function K (? ) of the kinetic terms. The fifth force is screened by the nonlinear K-mouflage mechanism if K'(? ) grows sufficiently fast for large negative ? . In the general nonspherically symmetric case, the fifth force is not aligned with the Newtonian force. For spherically symmetric static matter density profiles, we show that the results depend on the potential function W-(y )=y K'(-y2/2 ) ; i.e., W-(y ) must be monotonically increasing to +? for y ?0 to guarantee the existence of a single solution throughout space for any matter density profile. Small radial perturbations around these static profiles propagate as travelling waves with a velocity greater than the speed of light. Starting from vanishing initial conditions for the scalar field and for a time-dependent matter density corresponding to the formation of an overdensity, we numerically check that the scalar field converges to the static solution. If W- is bounded, for high-density objects there are no static solutions throughout space, but one can still define a static solution restricted to large radii. Our dynamical study shows that the scalar field relaxes to this static solution at large radii, whereas spatial gradients keep growing with time at smaller radii. If W- is not bounded but nonmonotonic, there is an infinite number of discontinuous static solutions. However, the Klein-Gordon equation is no longer a well-defined hyperbolic equation, which leads to complex characteristic speeds and exponential instabilities. Therefore, these discontinuous static solutions are not physical, and these models are not theoretically sound. Such K-mouflage scenarios provide an example of theories that can appear viable at the cosmological level, for the cosmological background and perturbative analysis, while being meaningless at a nonlinear level for small-scale configurations. This shows the importance of small-scale nonlinear analysis of screening models. All healthy K-mouflage models should satisfy K'>0 , and W±(y )=y K'(±y2/2 ) are monotonically increasing to +? when y ?0 .

  19. Integrating science with farmer knowledge: Sorghum diversity management in north-east Ghana

    OpenAIRE

    Kudadjie, C.Y.

    2006-01-01

    Keywords:   Convergence of sciences, diversity management, experimentation, farmer knowledge, genetic diversity, Ghana, plant variation, private sector, research, Sorghum bicolor (L.)Moench, small-scale farmers, seed quality.Sub-optimal impact of agricultural research is connected to lack of involvement of farmers. This is especially true forAfricawhere problems are diverse and complex. Farmer participation might help research to become better focused and resulting technologies more adopte...

  20. Beyond the field : Impact of Farmer Field Schools on food security and poverty alleviation

    OpenAIRE

    Lilleør, Helene Bie; Larsen, Anna Folke

    2013-01-01

    In this paper, we estimate the impact of a farmer field school intervention among small scale farmers in Northers Tanzania. Unlike previous farmer field school evaluations, we go beyond the immediate agricultural impact and estimate the impact of farmer field school participation in the pre-specified development objects, namely poverty alleviation and food security among participating households. We wxploit the implementation design of a gradual project roll-out to establish a quasi-experimen...

  1. TURBULENT SMALL-SCALE DYNAMO ACTION IN SOLAR SURFACE SIMULATIONS

    International Nuclear Information System (INIS)

    We demonstrate that a magneto-convection simulation incorporating essential physical processes governing solar surface convection exhibits turbulent small-scale dynamo action. By presenting a derivation of the energy balance equation and transfer functions for compressible magnetohydrodynamics, we quantify the source of magnetic energy on a scale-by-scale basis. We rule out the two alternative mechanisms for the generation of the 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 that 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.

  2. Optimal feeding systems for small-scale dairy herds in the North West Province, South Africa

    Scientific Electronic Library Online (English)

    N. Patience, Manzana; Cheryl M.E., McCrindle; P. Julius, Sebei; Leon, Prozesky.

    2014-01-01

    Full Text Available ABSTRACT Land redistribution was legislated in 1994; it was designed to resolve historical imbalances in land ownership in South Africa. Between 2002 and 2006, a longitudinal observational study was conducted with 15 purposively selected small-scale dairy farmers in a land redistribution project in [...] Central North West Province. Four farmers left the project over the period. For the purposes of this study, a small-scale dairy farm was defined as a farm that produces less than 500 L of milk a day, irrespective of the number of cows or size of the farm. The study was conducted in three phases. In the first phase, situational analysis using participatory rural appraisal (PRA) and observation was used to outline the extent of the constraints and design appropriate interventions. Feeds that were used were tested and evaluated. In the second phase, three different feeding systems were designed from the data obtained from PRA. These were: (1) A semi-intensive farm-based ration using available crops, pastures and crop residues with minimal rations purchased. (2) An intensive, zero-grazing dairy system using a total mixed ration. (3) A traditional, extensive or dual-purpose system, where the calf drank from the cow until weaning and milking was done only once a day. In the third phase, adoption was monitored. By July 2006, all remaining farmers had changed to commercially formulated rations or licks and the body condition score of the cows had improved. It was concluded that veterinary extension based on PRA and a holistic systems approach was a good option for such complex problems. Mentoring by commercial dairy farmers, veterinary and extension services appeared to be viable. Further research should be done to optimise the traditional model of dairy farming, as this was relatively profitable, had a lower risk and was less labour intensive.

  3. Small-scale European forestry, an anticommons?

    Directory of Open Access Journals (Sweden)

    Achim Schlueter

    2008-07-01

    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.

  4. Galaxy alignment on large and small scales

    CERN Document Server

    Kang, X; Wang, Y O; Dutton, A; Macciò, A

    2014-01-01

    Galaxies are not randomly distributed across the universe but showing different kinds of alignment on different scales. On small scales satellite galaxies have a tendency to distribute along the major axis of the central galaxy, with dependence on galaxy properties that both red satellites and centrals have stronger alignment than their blue counterparts. On large scales, it is found that the major axes of Luminous Red Galaxies (LRGs) have correlation up to 30Mpc/h. Using hydro-dynamical simulation with star formation, we investigate the origin of galaxy alignment on different scales. It is found that most red satellite galaxies stay in the inner region of dark matter halo inside which the shape of central galaxy is well aligned with the dark matter distribution. Red centrals have stronger alignment than blue ones as they live in massive haloes and the central galaxy-halo alignment increases with halo mass. On large scales, the alignment of LRGs is also from the galaxy-halo shape correlation, but with some ex...

  5. Small Scale Variations in Carbon Oxygen Ratio

    International Nuclear Information System (INIS)

    The aim of the research reported here is the development of a methodology for the measurement of small scale variations in chemical elements concentrations, in particular of carbon - oxygen ratio. Knowledge of the C/O ratio is of importance to many problems in various fields. Here we single out the application in obtaining important information about the oil fields. The most fundamental reservoir parameters - oil, gas and water content - are critical factors in determining how each oil field should be developed. It is well established that carbon to oxygen ratio log yields accurate and repeatable data that can be used to identify and monitor reserves depletion. Recent improvements in neutron generator and gamma detector technologies resulted in small devices which allowed through-tubing measurements. Although the ratio of carbon and oxygen yields is a measure of the amount of oil around the tool it should be realized that a carbon signal can originate from several sources including the borehole, the cement behind the casing, the formation rock and the formation fluid. In order to evaluate these contributions individually we are proposing the modification of the neutron generator by insertion of segmented associated alpha particle detector. From the measurement of time of flight spectra (alpha particle detector - start signal; gamma ray detector - stop signal) it would be possible to determine the location of gamma ray producing voxel and in such a way to determine radial variations in several chemical elements concentrations, in particular of carbon to oxygen ratio. (authors)

  6. Water power small scale hydro. Elan Valley

    International Nuclear Information System (INIS)

    The Elan Valley small-scale hydro project, which is owned and operated by Hyder Industrial Ltd, is located on the Elan Valley estate in the Cambrian Mountains in mid-Wales. Five reservoirs and four impounding dams were built in the Elan and Claerwen river valleys during the first half of the 20th century to supply water to Birmingham. Following the award of a contract under the Government's third non-Fossil Fuel Obligation Order (NFFO-3) to supply 4.2 MW of electricity to the National Grid during the 1990s, Hyder refurbished the original turbines at one location and built new units at four others. The existing water infrastructure was utilised. The total cost of the scheme, which generated some 35,700 MWh of electricity between May 1997 and March 1999, was 5.2 million pounds sterling. Details of the power generation units at the five hydro power stations, the power output, power transmission, planning requirements, measures taken by Hyder to minimise the scheme's environmental impact and the scheme's benefits are given

  7. Dairy goat keeping in the humid tropics :a case study of small-scale farming systems in Zanzibar

    OpenAIRE

    Stone, Tiffanie

    2014-01-01

    Dairy goats, recently introduced to Zanzibar, play an important role in many small-scale farming systems, improving both income and household nutrition. A survey of 193 dairy goat farmers in Zanzibar was conducted in 2013. The aim was to understand animal husbandry practices, benefits and challenges of dairy goat keeping, and to design support that is useful and encourages economic, environmental and socially sustainable integration of dairy goats in the humid tropics. In 116 questions, the ...

  8. Small scale imaging using ultrasonic tomography

    International Nuclear Information System (INIS)

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

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

    International Nuclear Information System (INIS)

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

  10. Tailor-made solutions : Small-scale biofuels and trade

    OpenAIRE

    Pacini, Henrique; Khatiwada, Dilip; Lo?nnqvist, Tomas

    2010-01-01

    In current debates on biofuels trade, the focus tends to be on large-scale production. However, the production of small-scale biofuels is better suited for many smaller developing and least-developed countries. Small-scale biofuels can bring many social and environmental benefits at the local level and, cumulatively, their production and utilisation can bring significant trade benefits.

  11. 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)

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

    2012-04-01

    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 d [...] e 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. 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 d [...] e 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. 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, So [...] uthern 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.

  12. 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)

    Erica Ell

    2012-04-01

    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.

  13. Impacts of Maize Policy Changes on Small Scale Farmers' Vulnerability to Exploitation in Nyimba District, Zambia

    OpenAIRE

    Njobvu, Idah

    2011-01-01

    Taking cognisance of the fact that SSFs the major producers of maize in Zambia were most affected by the 1991 agricultural policy reforms, from 2005 onward, the state became very active in the maize market and production systems in order to mitigate their problems. The main objective of this study is to investigate to what extent the maize policy changes have contributed to the SSFs’ vulnerability to exploitation. This information will be of use in the policy formulation process to ensure tha...

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

    OpenAIRE

    Majory Ongie Meliko; Oni, Stephen A.

    2011-01-01

    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 severi...

  15. Ginger (Zingiber officinale Roscoe) Production Efficiency and Constraints Among Small Scale Farmers in Southern Kaduna, Nigeria

    OpenAIRE

    Titilayo J. Ayodele; Banake E. Sambo

    2014-01-01

    Ginger (Zingiber officinale Roscoe) is mostly grown in southern Kaduna Sate, the traditional home of ginger in Nigeria. Its production was boosted with the aim of generating internal trade for the people and improved foreign exchange earnings for Nigeria. However, ginger yields in Nigeria are comparatively very low; and this is ascribed to various factors such as poor agronomic practices, unimproved varieties, laborious farming, harvesting and processing operations amongst others. It is again...

  16. A Guide to Bundling Small-scale CDM Projects

    International Nuclear Information System (INIS)

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-12-01

    The aim of the project is to develop production conditions, methods and technology of small-scale peat production to such a level that the productivity is improved and the competitivity maintained. 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 for 3.3 TWh and that of other peat 265 000 m{sup 3}. The total production of energy peat (large-scale producers Vapo Oy and Turveruuki Oy) amounted for 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 for 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 share of small-scale producers of other peat production was 18 %. The results deviate clearly from those obtained in a study of small-scale production in 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. (orig.) 8 refs. BIOENERGY Research Programme

  18. Development of small-scale production; Pienturvetuotannon kehittaeminen

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-07-01

    The aim of the project was to develop production conditions, methods and technology of small-scale peat production to such a level that the productivity is improved and competitivity maintained. 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) 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 the energy peat, 11 % of milled peat and 38 % of sod peat. The proportion of small-scale producers was 18 % of the 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. (orig.)

  19. Development of small-scale production; Pienturvetuotannon kehittaeminen

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-12-31

    The aim of the project was to develop production conditions, methods and technology of small-scale peat production to such a level that the productivity is improved and competitivity maintained. 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) 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 the energy peat, 11 % of milled peat and 38 % of sod peat. The proportion of small-scale producers was 18 % of the 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. (orig.)

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

    OpenAIRE

    Agomuo Florence Ozioma; Orisakwe Lambert

    2012-01-01

    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 educatio...

  1. The potential for small scale hydropower development in the US

    International Nuclear Information System (INIS)

    In an earlier paper (), the potential for small scale hydropower to contribute to US renewable energy supplies, as well as reduce current carbon emissions, was investigated. It was discovered that thousands of viable sites capable of producing significant amounts of hydroelectric power were available throughout the United States. The primary objective of this paper is to determine the cost-effectiveness of developing these small scale hydropower sites. Just because a site has the necessary topographical features to allow small scale hydropower development, does not mean that it should be pursued from a cost-benefit perspective, even if it is a renewable energy resource with minimal effects on the environment. This analysis finds that while the average cost of developing small scale hydropower is relatively high, there still remain hundreds of sites on the low end of the cost scale that are cost-effective to develop right now.

  2. Financing small scale wind energy projects in the UK

    International Nuclear Information System (INIS)

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

  3. Hopewell Furnace NHS Small Scale Features (Linear Features)

    National Park Service, Department of the Interior — This shapefile represents the linear small scale features found at Hopewell Furnace National Historic Site based on the Cultural Landscape Report completed in...

  4. Small Scale Mechanization of Thinning in Artificial Coniferous Plantation

    OpenAIRE

    Serena Savelli; Raffaele Cavalli; Sanzio Baldini; Rodolfo Picchio

    2010-01-01

    In Italy, where conventional forests have a protective rather than productive purpose, some silvicultural operations as first and second thinning could be carried out in an economic way adopting systems based on small scale mechanization. Authors tested a system based on small scale mechanization for bunching and skidding operations, using an All Terrain Vehicle (ATV), a compact, agile and versatile vehicle that adapts well to dense and rather inaccessible forests, such as forests of artifici...

  5. Identifying Lenses with Small-Scale Structure. I. Cusp Lenses

    OpenAIRE

    Keeton, Charles R.; Gaudi, B. Scott; Petters, A. O.

    2002-01-01

    The inability of standard models to explain the flux ratios in many 4-image gravitational lenses has been cited as evidence for significant small-scale structure in lens galaxies. That claim has generally relied on detailed lens modeling, so it is both model dependent and somewhat difficult to interpret. We present a more robust and generic method for identifying lenses with small-scale structure. For a close triplet of images associated with a source near a cusp caustic, th...

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

    OpenAIRE

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

    2007-01-01

    Yemen is one of the poorest countries in the world. The development of its fishery sector is increasingly being mentioned as a source of livelihood creation. The aims of this paper are to: (a) provide an overview of the institutional environment in which small-scale fishermen in Yemen operate; (b) investigate the constraints they face; and (c) discuss the potential role that co-operatives could play in such development. Small-scale fisheries in Yemen are increasingly important, yet they strug...

  7. Abelian Higgs Cosmic Strings: Small Scale Structure and Loops

    OpenAIRE

    Hindmarsh, Mark; Stuckey, Stephanie; Bevis, Neil

    2008-01-01

    Classical lattice simulations of the Abelian Higgs model are used to investigate small scale structure and loop distributions in cosmic string networks. Use of the field theory ensures that the small-scale physics is captured correctly. The results confirm analytic predictions of Polchinski & Rocha [1] for the two-point correlation function of the string tangent vector, with a power law from length scales of order the string core width up to horizon scale with evidence to su...

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

    International Nuclear Information System (INIS)

    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. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-12-01

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

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

    Science.gov (United States)

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

    2013-04-01

    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.

  11. Financing Sustainable Small-Scale Forestry: Lessons from Developing National Forest Financing Strategies in Latin America

    Directory of Open Access Journals (Sweden)

    Herman Savenije

    2010-12-01

    Full Text Available The problems that hamper the financing of sustainable forest management (SFM are manifold and complex. However, forestry is also facing unprecedented opportunities. The multiple functions and values of forests are increasingly recognized as part of the solution to pressing global issues (e.g., climate change, energy scarcity, poverty, environmental degradation, biodiversity loss and raw material supply. Emerging initiatives to enhance forest carbon stocks and cut greenhouse gas emissions associated with forest clearing (known as REDD+, together with voluntary carbon markets, are offering additional funding options for SFM. Indigenous peoples, local communities and small scale farmers feature as key players in the discourse on implementing such initiatives. Based on the experience of countries developing national forest financing strategies and instruments, we suggest the following points be considered when financing such initiatives, particularly for small scale forestry: (1 Integrate financing of REDD+ and similar initiatives within broader national strategies for SFM financing; (2 Design REDD+ finance mechanisms that are ‘community ready’, i.e., tailored to local realities; (3 Consider existing livelihood strategies as the starting point; (4 Build on existing structures, but be mindful of their strengths and weaknesses; (5 Be strategic with your priority actions; and (6 Promote innovation, knowledge sharing and information exchange.

  12. Small scale renewable energy resource assessment for Newfoundland

    International Nuclear Information System (INIS)

    This paper discussed the potential for small-scale hydro and wind power projects in Newfoundland. The province currently uses thermal generation for 20 per cent of its energy requirements, despite the fact that good wind and hydro resources are available. The province may soon construct a multi-billion dollar transmission line in order to import energy from Labrador to replace thermal generation on the island. The aim of the study was to determine if small-scale hydro and wind power could replace current thermal generation using a simplified island system simulation. The study showed that small-scale hydro potential represents approximately 1000 MW of energy that is technically feasible. The wind resource potential of the island is also very high, with a high wind penetration capability. Updates to transmission and control systems are required to enable small-scale hydro and wind development in the province. It was concluded that a combination of small-scale hydro and wind power can be used to replace the province's thermal energy requirements. 38 refs., 3 tabs., 3 figs

  13. The financial sustainability and socio-economic contribution of small-scale sugar-cane growers in Mpumalanga Province

    OpenAIRE

    Cloete, Riekie

    2013-01-01

    Small-scale sugar-cane farming came to Mpumalanga Province in the 1990s. As result of the Nkomazi Irrigation Expansion Programme, 34 projects with farms of on average size of seven hectares were initially allocated by Government to potential farmers in rural areas. This was done to enable them to generate income from sugar-cane to support their families. The initial expectations for the success of the programme were high, but they did not realise as anticipated. The yield results for the firs...

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

    International Nuclear Information System (INIS)

    Because of a number of developments (altered budgets of Dutch ministries and implementation of environmental policy plans of energy distribution companies in the Netherlands) the 1993 analyses of the effects of a small-scale consumer levy on the emission of CO2 are updated. First, attention is paid to the conservation impetus as a result of an increase of the energy price for small-scale consumers. Next, the effects that can occur as a consequence of the presently suggested form of the levy (in particular, the exemption of renewable energy and waste heat) are discussed. Subsequently, the alterations of other policy tools, that are necessary in case a higher effectiveness of conservation measures is realized, are dealt with. The direct effect of a higher energy price on the saving behavior of the small-scale consumers is calculated by means of the CENECA-model. 4 tabs., 1 appendix, 8 refs

  15. Contributions of small scales to statistics of Hall MHD turbulence

    International Nuclear Information System (INIS)

    A direct numerical simulation of decaying, homogeneous and isotropic turbulence of the incompressible Hall magnetohydrodynamic equations is carried out to clarify its statistical natures. Contributions of small scales to the statistics are examined. It is shown that the probability density function (PDF) of the enstrophy density is well characterized by the Gaussian distribution when the short wave number coefficients are removed, even though the vortex field shows intermittent structures. It is also shown that the local vortex structures are aligned to the magnetic field lines especially when the turbulent field is under developing and small scales are going to be excited. The alignment is lost in the relaxation process, suggesting the small scale current density field is less affected by the dissipations than the vorticity field. (author)

  16. Evaluation of Small-Scale Laterally Loaded Monopiles in Sand

    DEFF Research Database (Denmark)

    Roesen, Hanne Ravn; Thomassen, Kristina

    2011-01-01

    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.

  17. Germination as a processing technique for soybeans in small-scale farming

    Scientific Electronic Library Online (English)

    N.C., Kayembe; C., Jansen van Rensburg.

    Full Text Available Heat processing is an effective way of reducing antinutritional factors (ANFs) in legumes, but requires expensive facilities and equipment. Accurate control of temperature is critical to avoid under- or overheating. Therefore, heat treatment of soybeans is not a viable option for the average small-s [...] cale farmer in remote areas. Germination and other traditional methods, namely soaking and dehulling, were evaluated as alternative processing methods for soybeans. The effect of the processing treatment on the level of different ANFs, nutritional composition and in vitro protein digestibility (IVPD) of soybean seeds was determined. Soybeans were soaked for 24 hours and allowed to germinate for one to six days. Soaked soybeans were manually dehulled. Changes within seeds were noted for nutritional and ANFs during germination. Crude protein and fat content increased with increasing number of days germinated, but germination caused a decrease in starch content. Dehulling also increased the crude protein and fat content of the seeds. All treatments caused a significant decrease in condensed tannins of the soybeans. Trypsin inhibitor levels were numerically lower after germinating, soaking and dehulling of seeds, but not significantly so. There were no changes in IVPD after treatment of the soybeans. It was concluded that germination for a period of three days effectively improved the nutritional value of soybeans and can be considered an alternative treatment of soybeans for the small-scale farmer where heat treatment is impractical or impossible.

  18. Small-Scale Anisotropies of Cosmic Rays from Relative Diffusion

    CERN Document Server

    Ahlers, Markus

    2015-01-01

    The arrival directions of multi-TeV cosmic rays show significant anisotropies at small angular scales. It has been argued that this small-scale structure can naturally arise from cosmic ray scattering in local turbulent magnetic fields that distort a global dipole anisotropy set by diffusion. We study this effect in terms of the power spectrum of cosmic ray arrival directions and show that the strength of small-scale anisotropies is related to properties of relative diffusion. We provide a formalism for how these power spectra can be inferred from simulations and motivate a simple analytic extension of the ensemble-averaged diffusion equation that can account for the effect.

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

    Directory of Open Access Journals (Sweden)

    Genesis Tambang Yengoh

    2010-08-01

    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.

  20. Simulating Small-Scale Object Stacking Using Stack Stability

    DEFF Research Database (Denmark)

    Kronborg Thomsen, Kasper; Kraus, Martin

    2015-01-01

    This paper presents an extension system to a closed-source, real-time physics engine for improving structured stacking behavior with small-scale objects such as wooden toy bricks. The proposed system was implemented and evaluated. The tests showed that the system is able to simulate several common stacking scenarios, which the base physics engine cannot simulate.

  1. Solar small-scale dynamo and polarity of sunspot groups

    CERN Document Server

    Sokoloff, D; Abramenko, V

    2015-01-01

    In order to clarify a possible role of small-scale dynamo in formation of solar magnetic field, we suggest an observational test for small-scale dynamo action based on statistics of anti-Hale sunspot groups. As we have shown, according to theoretical expectations the small-scale dynamo action has to provide a population of sunspot groups which do not follow the Hale polarity law, and the density of such groups on the time-latitude diagram is expected to be independent on the phase of the solar cycle. Correspondingly, a percentage of the anti-Hale groups is expected to reach its maximum values during solar minima. For several solar cycles, we considered statistics of anti-Hale groups obtained by several scientific teams, including ours, to find that the percentage of anti-Hale groups becomes indeed maximal during a solar minimum. Our interpretation is that this fact may be explained by the small-scale dynamo action inside the solar convective zone.

  2. Smoke emissions in small-scale burning of wood

    International Nuclear Information System (INIS)

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

  3. Abelian Higgs Cosmic Strings: Small Scale Structure and Loops

    CERN Document Server

    Hindmarsh, Mark; Bevis, Neil

    2008-01-01

    Classical lattice simulations of the Abelian Higgs model are used to investigate small scale structure and loop distributions in cosmic string networks. Use of the field theory ensures that the small-scale physics is captured correctly. The results confirm analytic predictions of Polchinski & Rocha [1] for the two-point correlation function of the string tangent vector, with a power law from length scales of order the string core width up to horizon scale with evidence to suggest that the small scale structure builds up from small scales. An analysis of the size distribution of string loops gives a very low number density, of order 1 per horizon volume, in contrast with Nambu-Goto simulations. Further, our loop distribution function does not support the detailed analytic predictions for loop production derived by Dubath et al. [2]. Better agreement to our data is found with a model based on loop fragmentation [3], coupled with a constant rate of energy loss into massive radiation. Our results show a stron...

  4. Small-Scale Retailers in an Island Town

    Directory of Open Access Journals (Sweden)

    Sivapalan Selvadurai

    2013-10-01

    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.

  5. DESIGN OF A SMALL ? SCALE SOLAR CHIMNEY FOR SUSTAINABLE POWER

    Science.gov (United States)

    After several months of design and testing it has been determined that a small scale solar chimney can be built using nearly any local materials and simple hand tools without needing superior construction knowledge. The biggest obstacle to over come was the weather conditions....

  6. Spatial nonlocality of the small-scale solar dynamo

    International Nuclear Information System (INIS)

    We explore the nature of the small-scale solar dynamo by tracking magnetic features. We investigate two previously explored categories of the small-scale solar dynamo: shallow and deep. Recent modeling work on the shallow dynamo has produced a number of scenarios for how a strong network concentration can influence the formation and polarity of nearby small-scale magnetic features. These scenarios have measurable signatures, for which we test using magnetograms from the Narrowband Filter Imager (NFI) on board Hinode. We find no statistical tendency for newly formed magnetic features to cluster around or away from network concentrations, nor do we find any statistical relationship between their polarities. We conclude that there is no shallow or 'surface' dynamo on the spatial scales observable by Hinode/NFI. In light of these results, we offer a scenario in which the subsurface field in a deep solar dynamo is stretched and distorted via turbulence, allowing the small-scale field to emerge at random locations on the photosphere.

  7. 2010 Thin Film & Small Scale Mechanical Behavior Gordon Research Conference

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Thomas Balk

    2010-07-30

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

  8. Shaping Component Leads for Small-Scale Production

    Science.gov (United States)

    Jan, Lawrence

    1987-01-01

    Simple tool makes it easy to bend leads of electronic components quickly and uniformly for assembly on circuit board. Useful in small-scale production of electronic circuits; saves labor but avoids cost of complicated machinery. Made in range of sizes to accommodate components in variety of dimensions.

  9. An Appraisal of Farmer Variety Selection in Drought Prone Areas and Its Implication to Breeding for Drought Tolerance

    OpenAIRE

    Xavier Mhike; Patrick Okori; Girma Tesfahun Kassie; Cosmos Magorokosho; Shamiso Chikobvu

    2012-01-01

    Maize production and productivity among small scale farmers of southern Africa is limited mainly by drought and low soil fertility. This study aimed at assessing how farmers prioritize selection of varieties for planting under drought stress and how this could help improve the breeding approaches for varieties for resource constrained farmers in marginal environments. A survey was conducted in two drought prone districts of Zimbabwe. Data collection was done using a structured questionnaire, ...

  10. Influence of guanxi, trust and farmer-specific factors on participation in emerging vegetable markets in China

    OpenAIRE

    Lu Hualiang; Trienekens, J.H.; Omta, S. W. F.; Feng, S.

    2008-01-01

    The fast development of market outlets (e.g., supermarkets, processing industries, international markets) in China provides rich opportunities for small-scale farmers to upgrade quality and increase income. However, the high level of transaction costs incurred in small-volume-based vegetable transactions hinders farmers from participating in these emerging markets. This article explores how personal relationships (called guanxi in China) and trust between farmers and their buyers influence tr...

  11. Development of small-scale peat production. Final report

    International Nuclear Information System (INIS)

    The objective of this three year project was to develop the production conditions, methods and technology of small-scale peat producers so that the profitability of small-scale peat production is improved and the competitiveness remains. The aim in 1996 was to determine the present situation of small-scale peat producers, and the research and development needs, as well as to prepare a development plan of the small-scale peat production. The aims for 1997 were: the diminishing of the environmental hazards and the run-off waters of the small-scale peat production, the intensification of the peat deliveries from small-scale peat production, and the reduction of the peat production costs by improving the degree of utilization of the equipment via common or shared use. According to the results of the study peat production in Finland in 1996 was 25.0 TWh in total. The share of milled peat was 91 % of the peat production, and that of sod peat 9.0 %. About 1 440 000 m3 of other than energy peat was produced. The share of energy peat producers, replying to the questionnaire was 13 % (3.3 TWh) and the share of other peat producers was 18 %. Peat was produced from the area of 59 000 ha, the share of small-scale peat producers was 9 250 ha corresponding to about 16 % of the total peat production area. The share of milled peat of the peat produced by small-scale peat producers was about 73 %. The number of peat produces replying to the questionnaire was 164. The level o to the questionnaire was 164. The level of water protection and other environmental protection of twelve peat producers in the Southern Ostrobothnia were studied. According to the survey the main shortages comprised too small or lacking settling ponds. Also other shortages in environmental protection were observed. Feedback on the survey, as well as guidance and suggestions for improvements were given to the producers. Deliveries of peat by the small-scale peat producers to the Rauhalahti power plant of Jyvaeskylaen Energiantuotanto Oy were reviewed in order to intensify the deliveries. By using new delivery regions it would be possible to reduce the number of lorries transporting the peat from the present 17 lorries to 9 lorries. The annual transportation amounts will be normalized and they would be increased from the present average of 53 000 m3 to 109 000 m3. The value of reducing of the waiting times would be about 1.0 FIM/m3 calculated on the basis of the total peat deliveries to the plant. The shared usage of the transportation devices of the Haku method by several producers might in some cases be profitable method for replacing the own pneumatic harvesters of peat producers. Hence the common production area should be at least 50 - 100 ha. The engine-rents determination principles were reviewed in the study. In addition to this it was calculated that on the basis of long-term weather condition data it would be possible to produce 250 - 300 m3 of milled peat along with the sod peat production without interfering the sod peat production by using hired milled peat machines. The profitability of the production depends, however, on the rent determined on the basis of the total usage rate of milled peat production machinery

  12. LLNL Small-Scale Friction sensitivity (BAM) Test

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, L.R.; Foltz, M.F.

    1996-06-01

    Small-scale safety testing of explosives, propellants and other energetic materials, is done to determine their sensitivity to various stimuli including friction, static spark, and impact. Testing is done to discover potential handling problems for either newly synthesized materials of unknown behavior, or materials that have been stored for long periods of time. This report describes the existing {open_quotes}BAM{close_quotes} Small-Scale Friction Test, and the methods used to determine the friction sensitivity pertinent to handling energetic materials. The accumulated data for the materials tested is not listed here - that information is in a database. Included is, however, a short list of (1) materials that had an unusual response, and (2), a few {open_quotes}standard{close_quotes} materials representing the range of typical responses usually seen.

  13. Working Capital Management of Small Scale Industries in Rajasthan

    Directory of Open Access Journals (Sweden)

    Bashar Matarneh

    2012-04-01

    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.

  14. Manufacture of a Biodegradable Detergent on Small Scale

    OpenAIRE

    Abdulla A. Aziz A. Majeed; Jairam Singh

    2010-01-01

    This paper deals with an aggregate planning for a small scale production unit using a network flow model for full utilization of its capacity to meet the changing forecasted demand .The formulation of the problem is done by using the given inventory capacity with backorders by making a trade-off among inventory costs , backlog costs, production and subcontracting costs. The total cost function and the constraint inequalities were developed assuming the cost functions to be linear. The paramet...

  15. Small Scale Solar ORC system for distributed power

    OpenAIRE

    Orosz, Matthew; Mueller, Amy; Quoilin, Sylvain; Hemond, Harold

    2009-01-01

    A solar thermal organic Rankine cycle (ORC) can provide affordable energy supplies in remote regions. The advent of low-cost medium temperature parabolic trough collectors and ORC technology taking advantage of mass produced fluid machinery from HVAC industries are enabling developments for the production of small scale autonomous power generation units. Construction and testing of this type of system is discussed, including benchmarking of scrolls expanders (up to 75% isentropic ...

  16. WTO and its Impact on Small Scale Industries in India

    OpenAIRE

    Anchal Singh

    2014-01-01

    Small Scale Industries have emerged as an engine of growth in several developed and developing countries of the world including India and has acquired a prominent place in our socio-economic development since Independence through their ever-increasing contribution to national income. However, with the advent of economic reforms in 1991 it had to face stiff competition from globalization and economic liberalization as it has allowed companies to increase their base of operation...

  17. Micro and small-scale generation in urban distribution networks

    OpenAIRE

    Acosta Alvarez, Jorge Luis; Alvarez, Jorge Luis Acosta; Acosta, Jorge Luis

    2013-01-01

    As the world moves towards a more sustainable development, the energy coming from fossil fuels still produces the greenhouse gases that threaten the world’s climate. The UK government has established targets for the penetration of renewable energy generation and low-carbon alternatives for the electricity production. One of these technologies is microgeneration. In 2006, the UK government launched the Microgeneration Strategy pushing forward micro and small-scale generation a...

  18. Statistics of small scale vortex filaments in turbulence

    OpenAIRE

    Biferale, Luca; Scagliarini, Andrea; Toschi, Federico

    2009-01-01

    We study the statistical properties of coherent, small-scales, filamentary-like structures in Turbulence. In order to follow in time such complex spatial structures, we integrate Lagrangian and Eulerian measurements by seeding the flow with light particles. We show that light particles preferentially concentrate in small filamentary regions of high persistent vorticity (vortex filaments). We measure the fractal dimension of the attracting set and the probability that two par...

  19. Small Scale Parallel Manipulator Kinematics for Flexible Snake Robot Application

    OpenAIRE

    Raisuddin Khan; Md. Masum Billah; Mitsuru Watenabe; Amir Akramin Shafie

    2014-01-01

    A small-scale parallel manipulator is designed in this paper. The kinematic analysis of the manipulator is also elucidated for the development of multilinked snake robot. A compliant central colum is used to connect two parallel platforms of Incompletely Restrained Positioning Mechanism (IRPM). The compliant column allows the configuration to achieve 3 DOFs with 3 tendons of active materials connected between the upper and loer platform of the mechanism. In particular, this investigation focu...

  20. Optimal Tracking Controller Design for a Small Scale Helicopter

    OpenAIRE

    Budiyono, Agus; Wibowo, Singgih S.

    2008-01-01

    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 co...

  1. Small-Scale Retailers in an Island Town

    OpenAIRE

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

    2013-01-01

    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 reta...

  2. Small scale experiments on severe slugging in flexible risers.

    OpenAIRE

    Ita, Eyamba

    2011-01-01

    Severe slugging is an undesirable unsteady multiphase flow phenomenon which occurs in riser-pipeline systems. During the course of this masters thesis work, a dynamic coupling has been shown to exist between this flow phenomenon and the flexible riser in which it occurs. To analyse the influence of this coupling, the cyclic displacement of the riser and the loads exerted by this cyclic displacement on the risers attachment point to a topside vessel have been evaluated.A small scale experimen...

  3. Small-scale reactor for data oriented process development

    OpenAIRE

    Richner, Gilles; Cap, Sébastien; Godany, Tamas; Billeter, Julien; Puxty, Graeme; Neuhold, Yorck-Michael; Hungerbühler, Konrad

    2007-01-01

    During the early stages of research and development chemical industry needs flexible and versatile tools to investigate chemical reaction systems. An important part of the optimisation of a process considering economic factors, risk analysis and environmental impacts is the determination of a reaction mechanism and its associated parameters (i.e. activation energies, rates and heat of reactions). We present here a new fully automated small-scale reaction calorimeter combining a power-compens...

  4. Probing small-scale intermittency with a fluctuation theorem

    OpenAIRE

    Nickelsen, D.; Engel, A.

    2012-01-01

    We characterize statistical properties of the flow field in developed turbulence using concepts from stochastic thermodynamics. On the basis of data from a free air-jet experiment, we demonstrate how the dynamic fluctuations induced by small-scale intermittency generate analogs of entropy-consuming trajectories with sufficient weight to make fluctuation theorems observable at the macroscopic scale. We propose an integral fluctuation theorem for the entropy production associa...

  5. Structure formation with suppressed small-scale perturbations

    OpenAIRE

    Schneider, Aurel

    2014-01-01

    All commonly considered dark matter scenarios are based on hypothetical particles with small but non-zero thermal velocities and tiny interaction cross-sections. A generic consequence of these attributes is the suppression of small-scale matter perturbations either due to free-streaming or due to interactions with the primordial plasma. The suppression scale can vary over many orders of magnitude depending on particle candidate and production mechanism in the early Universe....

  6. Scaling and Small Scale Structure in Cosmic String Networks

    OpenAIRE

    Vincent, Graham R.; Hindmarsh, Mark; Sakellariadou, Mairi(Department of Physics, King's College London, University of London, Strand, London, WC2R 2LS United Kingdom)

    1996-01-01

    We examine the scaling properties of an evolving network of strings in Minkowski spacetime and study the evolution of length scales in terms of a 3-scale model proposed by Austin, Copeland and Kibble (ACK). We find good qualitative and some quantitative agreement between the model and our simulations. We also investigate small-scale structure by altering the minimum allowed size for loop production E_c. Certain quantities depend significantly on this parameter: for example t...

  7. Effect of generator usage on small scale businesses in Nigeria

    OpenAIRE

    Ikhuosho-Asikhia, Juliet

    2014-01-01

    Energy has a major impact on socio-economic development by playing a key role in economic, social and political advancement of any Nation. Inadequate supply of energy limits advancement in all spheres thereby causing depreciation in the quality of life among citizens. Small scale businesses in Nigeria also have their fair share of the effects of inadequate energy supply in Nigeria. The aim of this study is to analyze the awareness, economic and environmental effects and attitudes of gener...

  8. The legalization of small scale mining in Colombia

    Directory of Open Access Journals (Sweden)

    Alexandra Urán

    2013-11-01

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

  9. Dislocation dynamics simulations of plasticity at small scales

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Caizhi

    2010-12-15

    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.

  10. Does small scale structure significantly affect cosmological dynamics?

    Science.gov (United States)

    Adamek, Julian; Clarkson, Chris; Durrer, Ruth; Kunz, Martin

    2015-02-01

    The large-scale homogeneity and isotropy of the Universe is generally thought to imply a well-defined background cosmological model. It may not. Smoothing over structure adds in an extra contribution, transferring power from small scales up to large. Second-order perturbation theory implies that the effect is small, but suggests that formally the perturbation series may not converge. The amplitude of the effect is actually determined by the ratio of the Hubble scales at matter-radiation equality and today-which are entirely unrelated. This implies that a universe with significantly lower temperature today could have significant backreaction from more power on small scales, and so provides the ideal testing ground for understanding backreaction. We investigate this using two different N-body numerical simulations-a 3D Newtonian and a 1D simulation which includes all relevant relativistic effects. We show that while perturbation theory predicts an increasing backreaction as more initial small-scale power is added, in fact the virialization of structure saturates the backreaction effect at the same level independently of the equality scale. This implies that backreaction is a small effect independently of initial conditions. Nevertheless, it may still contribute at the percent level to certain cosmological observables and therefore it cannot be neglected in precision cosmology. PMID:25699430

  11. Empirical spatial econometric modelling of small scale neighbourhood

    Science.gov (United States)

    Gerkman, Linda

    2012-07-01

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

  12. Abelian Higgs cosmic strings: Small-scale structure and loops

    International Nuclear Information System (INIS)

    Classical lattice simulations of the Abelian Higgs model are used to investigate small-scale structure and loop distributions in cosmic string networks. Use of the field theory ensures that the small-scale physics is captured correctly. The results confirm analytic predictions of Polchinski and Rocha 29 for the two-point correlation function of the string tangent vector, with a power law from length scales of order the string core width up to horizon scale. An analysis of the size distribution of string loops gives a very low number density, of order 1 per horizon volume, in contrast with Nambu-Goto simulations. Further, our loop distribution function does not support the detailed analytic predictions for loop production derived by Dubath et al. 30. Better agreement to our data is found with a model based on loop fragmentation 32, coupled with a constant rate of energy loss into massive radiation. Our results show a strong energy-loss mechanism, which allows the string network to scale without gravitational radiation, but which is not due to the production of string width loops. From evidence of small-scale structure we argue a partial explanation for the scale separation problem of how energy in the very low frequency modes of the string network is transformed into the very high frequency modes of gauge and Higgs radiation. We propose a picture of string network evolution, which reconciles the apparent differences between Nambu-Goto and field theory simulations.bu-Goto and field theory simulations.

  13. Extraction of Extended Small-Scale Objects in Digital Images

    Science.gov (United States)

    Volkov, V. Y.

    2015-05-01

    Detection and localization problem of extended small-scale objects with different shapes appears in radio observation systems which use SAR, infra-red, lidar and television camera. Intensive non-stationary background is the main difficulty for processing. Other challenge is low quality of images, blobs, blurred boundaries; in addition SAR images suffer from a serious intrinsic speckle noise. Statistics of background is not normal, it has evident skewness and heavy tails in probability density, so it is hard to identify it. The problem of extraction small-scale objects is solved here on the basis of directional filtering, adaptive thresholding and morthological analysis. New kind of masks is used which are open-ended at one side so it is possible to extract ends of line segments with unknown length. An advanced method of dynamical adaptive threshold setting is investigated which is based on isolated fragments extraction after thresholding. Hierarchy of isolated fragments on binary image is proposed for the analysis of segmentation results. It includes small-scale objects with different shape, size and orientation. The method uses extraction of isolated fragments in binary image and counting points in these fragments. Number of points in extracted fragments is normalized to the total number of points for given threshold and is used as effectiveness of extraction for these fragments. New method for adaptive threshold setting and control maximises effectiveness of extraction. It has optimality properties for objects extraction in normal noise field and shows effective results for real SAR images.

  14. Small-scale clumps in the Galactic halo

    International Nuclear Information System (INIS)

    A mass function of small-scale dark matter clumps is calculated. We take into account the tidal destruction of clumps at early stages of structure formation starting from a time of clump detachment from the Universe expansion. Only a small fraction of these clumps, ?0.1%, in each logarithmic mass interval ? log M ? 1 survives the stage of hierarchical clustering. We calculate the probability of surviving of the remnants of dark matter clumps in the Galaxy by modelling the tidal destruction of the small-scale clumps by disk and stars. It is demonstrated that a substantial fraction of clump remnants may survive through the tidal destruction during the lifetime of the Galaxy if a radius of core is rather small. The resulting mass spectrum of survived clumps is extended down to the mass of the core of the cosmologically produced clumps with a minimal mass. The survived dense remnants of tidally destructed clumps provides a large contribution to the annihilation signal in the Galaxy. We describe the anisotropy of dark matter clump distribution caused by tidal destruction of clumps in the Galactic disk. A corresponding annihilation of dark matter particles in small-scale clumps produces the anisotropic gamma-ray signal with respect to the Galactic disk.

  15. Spatial Nonlocality of the Small-Scale Solar Dynamo

    CERN Document Server

    Lamb, Derek A; DeForest, Craig E

    2014-01-01

    We explore the nature of the small-scale solar dynamo by tracking magnetic features. We investigate two previously-explored categories of the small-scale solar dynamo: shallow and deep. Recent modeling work on the shallow dynamo has produced a number of scenarios for how a strong network concentration can influence the formation and polarity of nearby small-scale magnetic features. These scenarios have measurable signatures, which we test for here using magnetograms from the Narrowband Filter Imager (NFI) on Hinode. We find no statistical tendency for newly-formed magnetic features to cluster around or away from network concentrations, nor do we find any statistical relationship between their polarities. We conclude that there is no shallow or "surface" dynamo on the spatial scales observable by Hinode/NFI. In light of these results, we offer a scenario in which the sub-surface field in a deep solar dynamo is stretched and distorted via turbulence, allowing the field to emerge at random locations on the photo...

  16. 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

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

    DEFF Research Database (Denmark)

    Kiilholma, Jenni; Stockmarr, Anders

    2010-01-01

    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.

  18. Proceedings of a workshop on agroforestry tree seeds for farmers

    OpenAIRE

    Lillesø, Jens-peter Barnekow

    2007-01-01

    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 project...

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

    OpenAIRE

    Théodore Munyuli

    2011-01-01

    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 ...

  20. Farmers’ Education and Farmers’ Wealth in Bangladesh

    Directory of Open Access Journals (Sweden)

    Abu Zafar Mahmudul Haq

    2015-01-01

    Full Text Available The impact of farmers’ education is examined with a view to evaluate the actual situation of farmers’ education in Bangladesh. Fifty samples were collected from two sub districts of the Gazipur district in Bangladesh. The selection of the study sites and collection of the samples such as the years of schooling of the farm household head, total income, farm size, number of earners of farm families, family size, years of farming experience of farm household head, number of times extension contacts and rice yield were done purposively. It is cleared from the study that education is necessary for farmers to raise their wealth. Results were derived through regression analysis. The study has also shown that size of family and years of farming experience contributed significantly to the wealth accumulation of farmers.

  1. The Contribution of Multiple Use Forest Management to Small Farmers’ Annual Incomes in the Eastern Amazon

    OpenAIRE

    Plinio Sist; Philippe Sablayrolles; Sophie Barthelon; Liz Sousa-Ota; Jean-François Kibler; Ademir Ruschel; Marcelo Santos-Melo; Driss Ezzine-de-Blas

    2014-01-01

    Small-scale farmers in the Brazilian Amazon collectively hold tenure over more than 12 million ha of permanent forest reserves, as required by the Forest Code. The trade-off between forest conservation and other land uses entails opportunity costs for them and for the country, which have not been sufficiently studied. We assessed the potential income generated by multiple use forest management for farmers and compared it to the income potentially derived from six other agricultural land uses...

  2. The Effect of Holstein X Meat Cattle Breeds Crosses(F1 on Meat Production Increasing in Small Scale Farms Conditions

    Directory of Open Access Journals (Sweden)

    L. Papa

    2010-01-01

    Full Text Available About 80 % of Albanian small scale farms farming 1-2 dairy cows. The small agriculture land surface on farm property (1-1,5 ha is the main limiting factor for cow’s number increasing. So the farmer interest is not to increasing the number of cows in their farm but to fattening of calf’s born both for nutritive need of the family and market. The main objective of the study was to show the effect of industrial crosses (F1 of Holstein Frison cows with meat breeds like as Piementese(P, Limousine(L, Kianina(C, Sharole(Sh and Markixhana(M on meat production increasing on small scale farms. To carried out this objective, two study methods were used: (i The survey - 284 small scale farms was observed in the Albanian coastal field and (ii Comparative essay of fattening calves (F1 in semi intensive small scale farm condition - 32 calves, F1 crosses of Holstein cows with above mentioned meat breeds were put in fattening in semi intensive small scale farm condition. 6 Holstein breed (H calves of 3-4 months age was used as control group. The feeding of animals was based on forages produced in farm: corn silage 30 % D.M, fresh alpha-alpha and its hay. 35 % of dry matter requirements were supplied by bought concentrate feedstuffs with 15 % crude protein on dry matter bases. The fattening period lasted 8 months . The average daily body weight increasing for each crosses and control group were respectively 889g (PxH, 998g (LxH, 850g (KxH, 1010g( ChxH, 953g (MxH and 702g (HxH. Multivariate analyses according to a linear model with constant factors ( genotype, sex, genotype x sex and covariance “live body weight in the beginning of experiment” showed that: (i The effect of crossbreds on average daily gain is evident under the small-scale farms conditions, also, (ii The average daily gain increases with 23 -38 % , depending on the type of crosses, (iii The crosses of dairy cattle with Limousine and Sharole result as most effective. The differences between F1 crosses of Markigiana, Kianine and Piemonteze are not statistically significant, (iv In semi intensive small scale farms the calf fattening can start from second month of life, (v The farmers even though small scale farm condition can produce more meat though the crossing of dairy cattle with meat breeds in comparison with pure dairy breed calves.

  3. A small-scale land-sparing approach to conserving biological diversity in tropical agricultural landscapes.

    Science.gov (United States)

    Chandler, Richard B; King, David I; Raudales, Raul; Trubey, Richard; Chandler, Carlin; Chávez, Víctor Julio Arce

    2013-08-01

    Two contrasting strategies have been proposed for conserving biological diversity while meeting the increasing demand for agricultural products: land sparing and land sharing production systems. Land sparing involves increasing yield to reduce the amount of land needed for agriculture, whereas land-sharing agricultural practices incorporate elements of native ecosystems into the production system itself. Although the conservation value of these systems has been extensively debated, empirical studies are lacking. We compared bird communities in shade coffee, a widely practiced land-sharing system in which shade trees are maintained within the coffee plantation, with bird communities in a novel, small-scale, land-sparing coffee-production system (integrated open canopy or IOC coffee) in which farmers obtain higher yields under little or no shade while conserving an area of forest equal to the area under cultivation. Species richness and diversity of forest-dependent birds were higher in the IOC coffee farms than in the shade coffee farms, and community composition was more similar between IOC coffee and primary forest than between shade coffee and primary forest. Our study represents the first empirical comparison of well-defined land sparing and land sharing production systems. Because IOC coffee farms can be established by allowing forest to regenerate on degraded land, widespread adoption of this system could lead to substantial increases in forest cover and carbon sequestration without compromising agricultural yield or threatening the livelihoods of traditional small farmers. However, we studied small farms (<5 ha); thus, our results may not generalize to large-scale land-sharing systems. Furthermore, rather than concluding that land sparing is generally superior to land sharing, we suggest that the optimal approach depends on the crop, local climate, and existing land-use patterns. PMID:23551570

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

    Directory of Open Access Journals (Sweden)

    Ngufor L. Atanga

    2013-12-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2002-11-01

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

  6. Small scale studies of production of fissium aerosols

    International Nuclear Information System (INIS)

    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.)

  7. Probing small-scale intermittency with a fluctuation theorem

    CERN Document Server

    Nickelsen, D

    2014-01-01

    We characterize statistical properties of the flow field in developed turbulence using concepts from stochastic thermodynamics. On the basis of data from a free air-jet experiment, we demonstrate how the dynamic fluctuations induced by small-scale intermittency generate analogs of entropy-consuming trajectories with sufficient weight to make fluctuation theorems observable at the macroscopic scale. We propose an integral fluctuation theorem for the entropy production associated with the energy transfer along the eddy-hierarchy and demonstrate its extreme sensitivity to the accurate description of the tails of the velocity distributions.

  8. Monitoring Results of a Small Scale CHCP System

    OpenAIRE

    Mendes, J. Farinha; Cardoso, João P.; Coelho, Ricardo; Costa, João P.; Fernández, David; Silva, António R.; Morgado, Miguel; Adão, Pedro

    2010-01-01

    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 within the PolySMART project. The CHCP system main constituents are a purpose made CHP prototype with an estimated 27kW maximum heat capacity and 9,6kW maximum electrical capacity and a TDC pro...

  9. Optimal Tracking Controller Design for a Small Scale Helicopter

    CERN Document Server

    Budiyono, Agus

    2008-01-01

    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.

  10. Working Capital Management of Small Scale Industries in Rajasthan

    OpenAIRE

    Bashar Matarneh

    2012-01-01

    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...

  11. 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

  12. Dimensional analysis of small-scale steam explosion experiments

    International Nuclear Information System (INIS)

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

  13. Small-Scale Fruit Production: A Comprehensive Guide

    Science.gov (United States)

    2001-01-01

    Created and maintained by Penn State University Agricultural Services, this guide is a resource for "people who wish to produce fruit on a small scale (on one acre or less) and who are not legally licensed to use pesticides." The guide discusses topics such as getting started, pruning and training fruit trees, pests and pesticides, and controlling wildlife damage. It also includes individual chapters for each fruit type (pome, stone, grapes, berries, kiwi, etc.). Each of these includes fruit-specific information on planting, nutrition, harvest, and pest management, among other topics. All in all, this is a well-organized and very handy resource for anyone planning or maintaining a fruit garden.

  14. Small Scale Industries and Economic Development: Special Reference to India

    OpenAIRE

    Dr. S. N. Babar

    2012-01-01

    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...

  15. Experimental investigation of small-scale gasification ofwoody biomass

    OpenAIRE

    Barrio, Maria

    2002-01-01

    A small-scale stratified downdraft gasifier has been built and operated under stable conditions using wood pellets as fuel and air as gasification agent. The problems observed during the preliminary experiments have been described and explained; they are mainly related to the stability of the process. The stable operation of the gasifier has been characterised by the gas composition and the product gas tar and particle content. The biomass feeding rate has varied between 4,5 and 6,5 kg/h. The...

  16. Performance of a Small-Scale, Variable Temperature Fixed Dome Digester in a Temperate Climate

    Directory of Open Access Journals (Sweden)

    Juan M. Castano

    2014-09-01

    Full Text Available Small-scale digesters, similar to popular Chinese designs, have the potential to address the energy needs of smaller dairy farmers in temperate U.S. climates. To assess this potential, a 1.14 m3 (300 gallon modified fixed-dome digester was installed and operated, at variable temperatures (5.3 to 27.9 °C typical of the Midwestern United States, from March 2010 to March 2011 (363 days. Temperature, gas production, and other variables were recorded. The system was fed with dilute dairy manure with 6% volatile solids (VS and an organic loading rate (OLR ranging from 0.83 to 2.43 kg volatile solids (VS/m3/day. The system was loaded with no interruption and exhibited no signs of inhibition from July 2010 to mid-November 2010 (129 days. During this period the digester temperature was over 20 °C with an average daily biogas production of 842 ± 69 L/day, a methane yield of 0.168 m3/kg VS added, and a Volatile Solids reduction of 36%. After the temperature dropped below 20 °C, the digester showed signs of inhibition and soured. These findings suggest that an ambient temperature, modified fixed dome digester could operate without temperature inhibition for approximately six months (169 days a year in a temperate climate when digester temperatures exceed 20 °C. However, during colder months the digester temperature must maintained above 20 °C for viable gas production year round.

  17. A small-scale anatomical dosimetry model of the liver

    Science.gov (United States)

    Stenvall, Anna; Larsson, Erik; Strand, Sven-Erik; Jönsson, Bo-Anders

    2014-07-01

    Radionuclide therapy is a growing and promising approach for treating and prolonging the lives of patients with cancer. For therapies where high activities are administered, the liver can become a dose-limiting organ; often with a complex, non-uniform activity distribution and resulting non-uniform absorbed-dose distribution. This paper therefore presents a small-scale dosimetry model for various source-target combinations within the human liver microarchitecture. Using Monte Carlo simulations, Medical Internal Radiation Dose formalism-compatible specific absorbed fractions were calculated for monoenergetic electrons; photons; alpha particles; and 125I, 90Y, 211At, 99mTc, 111In, 177Lu, 131I and 18F. S values and the ratio of local absorbed dose to the whole-organ average absorbed dose was calculated, enabling a transformation of dosimetry calculations from macro- to microstructure level. For heterogeneous activity distributions, for example uptake in Kupffer cells of radionuclides emitting low-energy electrons (125I) or high-LET alpha particles (211At) the target absorbed dose for the part of the space of Disse, closest to the source, was more than eight- and five-fold the average absorbed dose to the liver, respectively. With the increasing interest in radionuclide therapy of the liver, the presented model is an applicable tool for small-scale liver dosimetry in order to study detailed dose-effect relationships in the liver.

  18. Profitability of Small-Scale Fisheries in Elmina, Ghana

    Directory of Open Access Journals (Sweden)

    Isaac Okyere

    2012-10-01

    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.

  19. MODELING THE VERY SMALL SCALE CLUSTERING OF LUMINOUS RED GALAXIES

    International Nuclear Information System (INIS)

    We model the small-scale clustering of luminous red galaxies (LRGs) in the Sloan Digital Sky Survey. Specifically, we use the halo occupation distribution formalism to model the projected two-point correlation function of LRGs on scales well within the sizes of their host halos (0.016 h -1 Mpc ? r ? 0.42 h -1 Mpc). We start by varying P(N|M), the probability distribution that a dark matter halo of mass M contains N LRGs, and assuming that the radial distribution of satellite LRGs within halos traces the Navarro-Frenk-White (NFW) dark matter density profile. We find that varying P(N|M) alone is not sufficient to match the small-scale data. We next allow the concentration of satellite LRG galaxies to differ from that of dark matter and find that this is also not sufficient. Finally, we relax the assumption of an NFW profile and allow the inner slope of the density profile to vary. We find that this model provides a good fit to the data and the resulting value of the slope is -2.17 ± 0.12. The radial density profile of satellite LRGs within halos is thus not compatible with that of the underlying dark matter, but rather is closer to an isothermal distribution.

  20. The small-scale structure of the Magellanic Stream

    International Nuclear Information System (INIS)

    Five regions in the northern part of the Magellanic Stream have been surveyed at high sensitivity with an angular resolution of 00.20 and a velocity resolution of 1.8 km s-1, in order to study their small-scale structure. The regions show narrow filamentary structure running parallel to the main direction of the Stream, and containing small cloud-like concentrations. Results are presented for the typical angular half-power widths and velocity half-power widths, typical masses, and preferential orientation of the clouds. The mean velocity differences between adjacent clouds appear to increase systematically towards the tip of the Stream, but there is no evidence for any variation in cloud parameters along the Stream, or for systematic motions within the individual clouds. The clouds appear to be unstable over the lifetime of the Stream as a whole, and some external containment mechanism seems to be necessary to preserve the small-scale structure. A number of possible mechanisms are discussed. (author)

  1. Small Scale Mechanization of Thinning in Artificial Coniferous Plantation

    Directory of Open Access Journals (Sweden)

    Serena Savelli

    2010-06-01

    Full Text Available In Italy, where conventional forests have a protective rather than productive purpose, some silvicultural operations as first and second thinning could be carried out in an economic way adopting systems based on small scale mechanization. Authors tested a system based on small scale mechanization for bunching and skidding operations, using an All Terrain Vehicle (ATV, a compact, agile and versatile vehicle that adapts well to dense and rather inaccessible forests, such as forests of artificial origin where no kind of intervention, particularly thinning, had ever been carried out. The vehicle was used for bunching, using an electric winch, and for skidding whole trees. The use of the ATV showed that it is a competitive vehicle with both traditional and cutting edge vehicles, performing a traction power average of 313 daN and PHS0 productivity variable from 1.20 to 3.05 td.m.h-1. Such figures confirm how in first thinning, on level ground but also on slopes (max 50%, over distances not exceeding 200 m, the ATV is a perfectly suitable vehicle. Furthermore, the impact of the vehicle on the ground and especially on the shallow soil horizons was negligible and had no effect on tree roots.

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

    DEFF Research Database (Denmark)

    Thomassen, Kristina; Roesen, Hanne Ravn

    2011-01-01

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

  3. Small-Scale Smart Grid Construction and Analysis

    Science.gov (United States)

    Surface, Nicholas James

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

  4. 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)

    Kafiriti, EM.

    2003-01-01

    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.

  5. Putting farmers first: reshaping agricultural research in West Africa

    Energy Technology Data Exchange (ETDEWEB)

    Pimbert, Michel

    2012-01-15

    How agricultural research is funded, organised, controlled and practised can have a huge impact on small-scale producers in the global South. In many countries, such research is driven by external funds, priorities and technological fixes, such as hybrid seeds, which can erode crop diversity. But food producers across the world are beginning to raise their voices to ensure that agricultural research better meets their needs and priorities. A series of farmer assessments and citizens' juries in West Africa has helped farmers assess existing approaches and articulate recommendations for policy and practice to achieve their own vision of agricultural research. In 2012, a high-level policy dialogue between farmers and the Alliance for a Green Revolution in Africa hopes to take this discussion to the next level and develop a shared agenda that can serve development and the public good.

  6. Determinants of Farmers’ Agricultural Diversification: The Case of Cambodia

    Directory of Open Access Journals (Sweden)

    Kimty Seng

    2014-08-01

    Full Text Available A Heckman sample selection approach is employed with the data on Cambodia Socio-Economic Survey CSES-2007 to explore price and non-price factors determining farmers’ crop diversification decision, and consequently affecting diversification intensity. "The findings suggest that high relative price discourages farmers from diversifying crops." Irrigation, agricultural equipment ownership and farming expenditure have significantly positive effects on the decision, and sequentially increasing the intensity. Arable land size per household member, agricultural and transportation equipments have positive correlation with the diversification decision. Small scale of farming is a major hindrance to the decision, and consequently reducing the intensity. Land dispute, one of the main institutional matters in Cambodia, is found to have significantly negative marginal-effect on farmers’ decision on crop diversification.

  7. Evaluation of Information and Communication Technology Utilization by Small Holder Banana Farmers in Gatanga District, Kenya

    Science.gov (United States)

    Mwombe, Simon O. L.; Mugivane, Fred I.; Adolwa, Ivan S.; Nderitu, John H.

    2014-01-01

    Purpose: The study was carried out to identify information communication technologies (ICTs) used in production and marketing of bananas, to determine factors influencing intensity of use of ICT tools and to assess whether use of ICT has a significant influence on adoption of tissue culture bananas by small-scale banana farmers in Gatanga…

  8. Small-scale lunar graben: Distribution, dimensions, and formation processes

    Science.gov (United States)

    French, Renee A.; Bina, Craig R.; Robinson, Mark S.; Watters, Thomas R.

    2015-05-01

    The Lunar Reconnaissance Orbiter Camera (LROC) is the first instrument to provide widespread coverage with a range of incidence angles at the resolution required to detect small-scale landforms. A sample (n = 238) of globally distributed, small-scale graben average 26 m wide and 179 m long. When dividing the population into those located within mare and highland regions, we observe that graben located within mare tend to be narrower, shorter, and more irregularly spaced than those in highland terrane. For graben associated with contractional landforms, those in mare are smaller in width and length than those in highlands; the same is true for graben independent of contractional landforms. Assuming a simple geometry, widths of mare graben associated with scarps or ridges are used to estimate the minimum depth range to a mechanical discontinuity (e.g., base of the regolith) resulting in values of ?4-48 m. These values are similar to the ranges estimated for regolith thickness from previous workers using Apollo 14 seismic data (3.9-8.5 m), crater counting techniques (8-33 m), crater morphology techniques (2.5-9 m), and crater blockiness (8-31 m). Widths of highland graben yield minimum depths of faulting of 209-296 m. While this range agrees well with models for regolith production (an older surface will have thicker regolith), this estimate likely does not represent the thickness of a mechanical unit due to the fragmented nature of the highland crust (it does not provide a defining boundary between bedrock and regolith). Spacing of mare graben not associated with contractional landforms is used to estimate maximum local mare unit thickness for two graben groups: 190 m for Posidonius and 296 m for Vitello. Maximum graben ages range from late Eratosthenian to early Copernican based on superposed and crosscut crater ages with a group of graben deforming ejecta from Copernicus crater. Data presented here provide further evidence of a globally distributed, young, small-scale graben population that has formed as a result of localized extension either from flexural bending or dilation due to contractional faulting or volcanic uplift, indicating a significant level of recent geologic activity.

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

    Science.gov (United States)

    Voulgari, Chrysoula; Utili, Stefano; Castellanza, Riccardo

    2015-04-01

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

  10. Improving the Management and Use of Water Resources for Small-Scale Irrigation Farming in the Garu Tempane District of Ghana

    Directory of Open Access Journals (Sweden)

    Amosah Jonah

    2014-10-01

    Full Text Available Small scale irrigation farming has been recognized as an important avenue for improving the well being of poor people living in arid and marginal areas of the world. The contribution of small scale irrigation can be seen in its ability to ensure food security as well as contribute to the income of farmers. In the Garu-Tempane District, small scale irrigation farming is a major source of livelihood for people in the district. Despite the importance of the irrigation schemes to dry season farming the schemes face challenges such as inadequate water, inadequate canals, choked and broken canals due to frequent breakdown and inadequate repairs which affect their effective operation. Although the major use of the dam waters was dry season farming, animal watering and fishing were also found to be significant uses of the dam waters. In north-eastern Ghana as it is in many parts of the third world, external development agencies support the formation of Water User Associations (WUAs for the management of community-based irrigation schemes. Although, the management of the schemes and the use of the dam is the responsibility of the community represented by the WUAs it was revealed by the study that, in the management of challenges that confront small scale irrigation schemes, WUAs depended on the supportive roles of traditional authorities as well as district assemblies for discharging their management responsibilities more effectively.

  11. Participatory approach: from problem identification to setting strategies for increased productivity and sustainability in small scale irrigated agriculture

    Science.gov (United States)

    Habtu, Solomon; Ludi, Eva; Jamin, Jean Yves; Oates, Naomi; Fissahaye Yohannes, Degol

    2014-05-01

    Practicing various innovations pertinent to irrigated farming at local field scale is instrumental to increase productivity and yield for small holder farmers in Africa. However the translation of innovations from local scale to the scale of a jointly operated irrigation scheme is far from trivial. It requires insight on the drivers for adoption of local innovations within the wider farmer communities. Participatory methods are expected to improve not only the acceptance of locally developed innovations within the wider farmer communities, but to allow also an estimation to which extend changes will occur within the entire irrigation scheme. On such a base, more realistic scenarios of future water productivity within an irrigation scheme, which is operated by small holder farmers, can be estimated. Initial participatory problem and innovation appraisal was conducted in Gumselassa small scale irrigation scheme, Ethiopia, from Feb 27 to March 3, 2012 as part of the EAU4FOOD project funded by EC. The objective was to identify and appraise problems which hinder sustainable water management to enhance production and productivity and to identify future research strategies. Workshops were conducted both at local (Community of Practices) and regional (Learning Practice Alliance) level. At local levels, intensive collaboration with farmers using participatory methods produced problem trees and a "Photo Safari" documented a range of problems that negatively impact on productive irrigated farming. A range of participatory methods were also used to identify local innovations. At regional level a Learning Platform was established that includes a wide range of stakeholders (technical experts from various government ministries, policy makers, farmers, extension agents, researchers). This stakeholder group did a range of exercise as well to identify major problems related to irrigated smallholder farming and already identified innovations. Both groups identified similar problems to productive smallholder irrigation: soil nutrient depletion, salinization, disease and pest resulting from inefficient irrigation practices, infrastructure problems leading to a reduction of the size of the command area and decrease in reservoir volume. The major causes have been poor irrigation infrastructure, poor on-farm soil and water management, prevalence of various crop pests and diseases, lack of inputs and reservoir siltation. On-farm participatory research focusing on soil, crop and water management issues, including technical, institutional and managerial aspects, to identify best performing innovations while taking care of the environment was recommended. Currently, a range of interlinked activities are implemented a multiple scales, combining participatory and scientific approaches towards innovation development and up-scaling of promising technologies and institutional and managerial approaches from local to regional scales. ____________________________ Key words: Irrigation scheme, productivity, innovation, participatory method, Gumselassa, Ethiopia

  12. Manufacture of a Biodegradable Detergent on Small Scale

    Directory of Open Access Journals (Sweden)

    Abdulla A. Aziz A. Majeed

    2010-12-01

    Full Text Available This paper deals with an aggregate planning for a small scale production unit using a network flow model for full utilization of its capacity to meet the changing forecasted demand .The formulation of the problem is done by using the given inventory capacity with backorders by making a trade-off among inventory costs , backlog costs, production and subcontracting costs. The total cost function and the constraint inequalities were developed assuming the cost functions to be linear. The parameters of objective function and the constraints were estimated from the economics of the plant. The values of the work force, overtime, backlog, amount subcontracted were determined for a planning horizon of six months using an LP computer package. This method of production scheduling took care of the fluctuating demand utilizing the full capacity of the plant.

  13. Emissions from small scale biomass combustion - Research needs

    International Nuclear Information System (INIS)

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

  14. Numerical simulation of a small-scale biomass boiler

    International Nuclear Information System (INIS)

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

  15. Transition from Large-Scale to Small-Scale Dynamo

    International Nuclear Information System (INIS)

    The dynamo equations are solved numerically with a helical forcing corresponding to the Roberts flow. In the fully turbulent regime the flow behaves as a Roberts flow on long time scales, plus turbulent fluctuations at short time scales. The dynamo onset is controlled by the long time scales of the flow, in agreement with the former Karlsruhe experimental results. The is governed by a generalized ? effect, which includes both the usual ? effect and turbulent diffusion, plus all higher order effects. Beyond the onset we find that this generalized ? effect scales as O(Rm-1), suggesting the takeover of small-scale dynamo action. This is confirmed by simulations in which dynamo occurs even if the large-scale field is artificially suppressed.

  16. Exergoeconomic analysis of small-scale biomass steam cogeneration

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-07-01

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

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

    International Nuclear Information System (INIS)

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

  18. Structure formation with suppressed small-scale perturbations

    CERN Document Server

    Schneider, Aurel

    2014-01-01

    All commonly considered dark matter scenarios are based on hypothetical particles with small but non-zero thermal velocities and tiny interaction cross-sections. A generic consequence of these attributes is the suppression of small-scale matter perturbations, either due to free-streaming or due to interactions with the primordial plasma. The suppression scale can vary over many orders of magnitude, depending on particle candidate and production mechanism in the early Universe. While nonlinear structure formation has been explored in great detail well above the suppression scale, the range around suppressed perturbations is still poorly understood. In this paper we study structure formation in the regime of suppressed perturbations, using both analytical techniques and numerical simulations. We develop simple and theoretically motivated recipes for the halo mass function, the expected number of satellites, and the halo concentrations, which are designed to work for power spectra with suppression at arbitrary s...

  19. Design and efficiency of a small-scale woodchip furnace

    Scientific Electronic Library Online (English)

    Carlos, Torres-Fuchslocher; Felipe, Varas-Concha.

    Full Text Available Although advances have been made in combustion efficiency in large-scale woodchip furnaces, less experimental results are available at the [...] s. This study describes the design and testing of a small-scale woodchip furnace that operates at a range of 9-18 kW. The efficiency test takes account of the feedstock Eucalyptus nitens, with three moisture contents and the combination of different air excess (?) and primary/secondary air ratios. The results reveal a maximum of combustion efficiency of 85% for the low moisture content sample (16%) at ?=1,5 and 82% for samples with 29% and 40% moisture content, at ?= 2,0 and 2,1 respectively. The integrated heat exchanger proved to be highly efficient by reducing gas temperature by up to 69% prior to its exit.

  20. Small-scale volcanoes on Mars: distribution and types

    Science.gov (United States)

    Broz, Petr; Hauber, Ernst

    2015-04-01

    Volcanoes differ in sizes, as does the amount of magma which ascends to a planetary surface. On Earth, the size of volcanoes is anti-correlated with their frequency, i.e. small volcanoes are much more numerous than large ones. The most common terrestrial volcanoes are scoria cones (active over most (if not all) of its history, a similar distribution of volcano size might be expected. Martian small-scale volcanoes were not intensely studied for a long time due to a lack of high-resolution data enabling their proper identification; however their existence and basic characteristics were predicted on theoretical grounds. Streams of new high-resolution images now enable discovering and studying kilometer-size volcanoes with various shapes in unprecedented detail. Several types of small-scale volcanoes in various regions on Mars were recently described. Scoria cones provide a record of magmatic volatile content and have been identified in Tharsis (Ulysses Colles), on flanks of large volcanoes (e.g., Pavonis Mons), in the caldera of Ulysses Patera, in chaotic terrains or other large depressions (Hydraotes Colles, Coprates Chasma) and in the northern lowlands. Tuff rings and tuff cones, formed as a result of water-magma interaction, seem to be relatively rare on Mars and were only tentatively identified in three locations (Nepenthes/Amenthes region, Arena Colles and inside Lederberg crater), and alternative interpretations (mud volcanoes) seem possible. Other relatively rare volcanoes seem to be lava domes, reported only from two regions (Acracida Planitia and Terra Sirenum). On the other hand, small shields and rootless cones (which are not primary volcanic landforms) represent widely spread phenomena recognized in Tharsis and Elysium. Based on these new observations, the distribution of small volcanoes on Mars seems to be much more widespread than anticipated a decade ago. There are sometimes significant differences in the final morphologies between Martian hypothesized and possible terrestrial analogs, despite fact that the physical processes behind volcano formation should be similar on both planets. For example, Martian scoria cones are ~2.6 times wider than terrestrial analogues, as lower gravity and atmospheric pressure enable wider dispersion of pyroclasts from the vent. In addition, exit velocities of ejected particles should be increased on Mars because the lower atmospheric pressure favors more rapid exsolution of dissolved gases from the magma, which also favors a wider dispersion of ejected particles. Therefore, care must be taken when applying terrestrial morphometric relationships to the interpretation of hypothesized volcanic features on Mars and other terrestrial bodies. As on Earth, small-scale volcanoes on Mars display diverse shapes and hence provide insight into diverse volcanic processes responsible for such variations. Those diverse processes may point to various mechanisms of magma ascent and eruption styles in dependency on magma properties (e.g., amount of volatiles) and the paleo-environment at the time of formation. Hence the investigation of small-scale volcanoes provides useful tool enabling us to deepen our knowledge about the variety and richness of volcanism on Mars.

  1. Scaling properties of small-scale fluctuations in magnetohydrodynamic turbulence

    CERN Document Server

    Perez, J C; Boldyrev, S; Cattaneo, F

    2014-01-01

    Magnetohydrodynamic (MHD) turbulence in the majority of natural systems, including the interstellar medium, the solar corona, and the solar wind, has Reynolds numbers far exceeding the Reynolds numbers achievable in numerical experiments. Much attention is therefore drawn to the universal scaling properties of small-scale fluctuations, which can be reliably measured in the simulations and then extrapolated to astrophysical scales. However, in contrast with hydrodynamic turbulence, where the universal structure of the inertial and dissipation intervals is described by the Kolmogorov self-similarity, the scaling for MHD turbulence cannot be established based solely on dimensional arguments due to the presence of an intrinsic velocity scale -- the Alfven velocity. In this Letter, we demonstrate that the Kolmogorov first self-similarity hypothesis cannot be formulated for MHD turbulence in the same way it is formulated for the hydrodynamic case. Besides profound consequences for the analytical consideration, this...

  2. Using dark energy to suppress power at small scales

    CERN Document Server

    Kunz, Martin; Sawicki, Ignacy

    2015-01-01

    The latest Planck results reconfirm the existence of a slight but chronic tension between the best-fit CMB and low-redshift observables: power seems to be consistently lacking in the late universe across a range of observables (e.g. weak lensing, cluster counts). We propose a two-parameter model for dark energy where the dark energy is sufficiently like dark matter at large scales to keep the CMB unchanged but where it does not cluster at small scales, preventing concordance collapse and erasing power. We thus exploit the generic scale-dependence of DE instead of the more usual time-dependence to address the tension in the data. The combination of CMB, distance and weak lensing data somewhat prefer our model to $\\Lambda$CDM, at $\\Delta\\chi^2=2.4$. Moreover, this improved solution has $\\sigma_8=0.79 \\pm 0.02$, consistent with the value implied by cluster counts.

  3. Small Scale Field Emergence and Its Impact on Photospheric Granulation

    CERN Document Server

    Yurchyshyn, V; Abramenko, V; Goode, P; Cao, W

    2012-01-01

    We used photospheric intensity images and magnetic field measurements from the New Solar Telescope in Big Bear and Helioseismic Magnetic Imager on board Solar Dynamics Observatory (SDO) to study the the effect that the new small-scale emerging flux induces on solar granulation. We report that emerging flux appears to leave different types of footprint on solar granulation: i) diffuse irregular patches of increased brightness, ii) well defined filament-like structures and accompanied bright points, and iii) bright point-like features that appear inside granules. We suggest that the type of the footprint depends on the intensity of emerging fields. Stronger fields, emerging as a part of large magnetic structure, create on the solar surface a well defined filamentary pattern with bright points at the ends of the filaments, while weak turbulent fields are associated with bright patches inside the host granule.

  4. Analytic Study of Small Scale Structure on Cosmic Strings

    CERN Document Server

    Polchinski, J; Polchinski, Joseph; Rocha, Jorge V.

    2006-01-01

    The properties of string networks at scales well below the horizon are poorly understood, but they enter critically into many observables. We argue that in some regimes, stretching will be the only relevant process governing the evolution. In this case, the string two-point function is determined up to normalization: the fractal dimension approaches one at short distance, but the rate of approach is characterized by an exponent that plays an essential role in network properties. The smoothness at short distance implies, for example, that cosmic string lensing images are little distorted. We then add in loop production as a perturbation and find that it diverges at small scales. This need not invalidate the stretching model, since the loop production occurs in localized regions, but it implies a complicated fragmentation process. Our ability to model this process is limited, but we argue that loop production peaks a few orders of magnitude below the horizon scale, without the inclusion of gravitational radiati...

  5. The challenge of small-scale repeats for indel discovery.

    Science.gov (United States)

    Narzisi, Giuseppe; Schatz, Michael C

    2015-01-01

    Repetitive sequences are abundant in the human genome. Different classes of repetitive DNA sequences, including simple repeats, tandem repeats, segmental duplications, interspersed repeats, and other elements, collectively span more than 50% of the genome. Because repeat sequences occur in the genome at different scales they can cause various types of sequence analysis errors, including in alignment, de novo assembly, and annotation, among others. This mini-review highlights the challenges introduced by small-scale repeat sequences, especially near-identical tandem or closely located repeats and short tandem repeats, for discovering DNA insertion and deletion (indel) mutations from next-generation sequencing data. We also discuss the de Bruijn graph sequence assembly paradigm that is emerging as the most popular and promising approach for detecting indels. The human exome is taken as an example and highlights how these repetitive elements can obscure or introduce errors while detecting these types of mutations. PMID:25674564

  6. Small Scale Parallel Manipulator Kinematics for Flexible Snake Robot Application

    Directory of Open Access Journals (Sweden)

    Raisuddin Khan

    2014-01-01

    Full Text Available A small-scale parallel manipulator is designed in this paper. The kinematic analysis of the manipulator is also elucidated for the development of multilinked snake robot. A compliant central colum is used to connect two parallel platforms of Incompletely Restrained Positioning Mechanism (IRPM. The compliant column allows the configuration to achieve 3 DOFs with 3 tendons of active materials connected between the upper and loer platform of the mechanism. In particular, this investigation focuses on the angular deflection of the upper platform with respect to the lower platform. The application here is aimed at developing an active linkable module that can be connected to one another so as to form a “snake robot” of sorts. For an arbitrary angular displacement of the platforms, the corresponding length of each tendon can be determined through inverse kinematics. From the experimental result, the extreme bending of the central column plane of 30° angular displacement with the of the horizontal axis.

  7. 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.)

  8. LLNL small-scale drop-hammer impact sensitivity test

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, L.R.; Foltz, M.F.

    1995-01-01

    Small-scale safety testing of explosives and other energetic materials is done to determine their sensitivity to various stimuli including friction, static spark, and impact. This testing is typically done to discover potential handling problems for either newly synthesized materials of unknown behavior or materials that have been stored for long periods of time. This report describes the existing ``ERL Type 12 Drop Weight Impact Sensitivity Apparatus``, or ``Drop Hammer Machine``, and the methods used to determine the impact sensitivity of energetic materials, Also discussed are changes made to both the machine and methods since the inception of impact sensitivity testing at LLNL in 1956. The accumulated data for the materials tested in not listed here, the exception being the discussion of those specific materials (primary calibrants: PETN, RDX, Comp-B3,and TNT; secondary calibrants: K-6, RX-26-AF, and TATB) used to calibrate the machine.

  9. CMB spectral distortions from small-scale isocurvature fluctuations

    CERN Document Server

    Chluba, Jens

    2013-01-01

    The damping of primordial perturbations at small-scales gives rise to distortions of the cosmic microwave background (CMB). Here the dependence of the distortion on the different types of cosmological initial conditions is explored, covering adiabatic, baryon/cold dark matter isocurvature, neutrino density/velocity isocurvature modes and some mixtures. The radiation transfer functions for each mode are determined and then used to compute the dissipative heating rates and spectral distortion signatures, utilizing both analytic estimates and numerical results from the thermalization code CosmoTherm. Along the way, the early-time super horizon behavior for the resulting fluid modes is derived in conformal Newtonian gauge, and tight-coupling transfer function approximations are given. CMB spectral distortions caused by different perturbation modes can be estimated using simple k-space window functions which are provided here. Neutrinos carry away some fraction of the primordial perturbation power, introducing an ...

  10. MeV Dark Matter and Small Scale Structure

    International Nuclear Information System (INIS)

    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 10-4 M#circle_dot# to 10-12 M#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 107M#circle_dot# to 104 M#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

  11. Small-scale power/heat production based on biomass

    International Nuclear Information System (INIS)

    Conventional energy production from biomass is most often used to produce steam, hot water or air heating. According to this conference paper, the maximum electric output is obtained in processes based on gasification of biomass in combined gas turbine/steam turbine systems. The efficiency increases with increasing plant size. Production cost decreases with increasing plant size. However, large plants producing 20 MW electric also produce 30 MW heat energy which must be utilized if the total efficiency is to be large. There is a potential for small systems (3 - 5 kw electric) for decentralized power/heat production. The paper surveys in brief various technologies for small-scale power/heat plants based on biomass: steam turbine, steam engine, gas turbine, Stirling engine, diesel engine/gas engine. 9 refs., 5 figs

  12. Small-scale resistance spot welding of austenitic stainless steels

    International Nuclear Information System (INIS)

    Small-scale resistance spot welding (SSRSW) was carried out for austenitic stainless steels. A weld lobe that shows the process window for making sound joints was obtained for type 304 stainless steel thin sheets, and the effects of welding current, force and weld time on joint strength and nugget size were investigated. The cooling rate that was estimated from the solidification cell size was approximately 2.4 x 105 K/s which is almost similar to that produced by laser beam welding. The microstructures of weld zones were almost fully austenitic due to the rapid solidification rate. Despite the fully austenitic microstructure, no hot cracking was found in types 302, 304, 316L, 310S and 347 austenitic stainless steels by SSRSW. Rapid cooling rate in SSRSW made it difficult to predict the microstructures from the conventional Schaeffler diagram

  13. Design and efficiency of a small-scale woodchip furnace

    Scientific Electronic Library Online (English)

    Carlos, Torres-Fuchslocher; Felipe, Varas-Concha.

    2015-04-01

    Full Text Available Although advances have been made in combustion efficiency in large-scale woodchip furnaces, less experimental results are available at the [...] s. This study describes the design and testing of a small-scale woodchip furnace that operates at a range of 9-18 kW. The efficiency test takes account of the feedstock Eucalyptus nitens, with three moisture contents and the combination of different air excess (?) and primary/secondary air ratios. The results reveal a maximum of combustion efficiency of 85% for the low moisture content sample (16%) at ?=1,5 and 82% for samples with 29% and 40% moisture content, at ?= 2,0 and 2,1 respectively. The integrated heat exchanger proved to be highly efficient by reducing gas temperature by up to 69% prior to its exit.

  14. First Principle Approach to Modeling of Small Scale Helicopter

    CERN Document Server

    Budiyono, A; Lesmana, H

    2008-01-01

    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...

  15. Small-scale Testing of Bucket Foundations in Sand

    DEFF Research Database (Denmark)

    Knudsen, BjØrn S.; Østergaard, Martin Underlin

    2013-01-01

    For offshore foundation structures, the loads are of varying nature both in magnitude and duration. For the bucket foundation the dissipation of the pore pressure is highly relevant since it greatly affects the strength of the structure. The build up of pore pressures with varying loading rate is therefore a highly relevant research subject. In computational models, e.g. FE-models, normally either a drained or an undrained behaviour is assumed. In real life, the behaviour is partially drained, which calls for a time-dependent model. Especially, the tracking of pore pressures in and around the bucket skirt will provide valuable information of the quasi-static behaviour. For a number of small-scale tests performed in the laboratory at Aalborg University, a bucket foundation will be loaded with varying velocity to investigate the dissipation and general behaviour of bucket foundations used as offshore support structures for wind turbines.

  16. Effects of thermal inflation on small scale density perturbations

    CERN Document Server

    Hong, Sungwook E; Lee, Young Jae; Stewart, Ewan D; Zoe, Heeseung

    2015-01-01

    In cosmological scenarios with thermal inflation, extra eras of moduli matter domination, thermal inflation and flaton matter domination exist between primordial inflation and the radiation domination of Big Bang nucleosynthesis. During these eras, cosmological perturbations on small scales can enter and re-exit the horizon, modifying the power spectrum on those scales. The largest modified scale, $k_\\mathrm{b}$, touches the horizon size when the expansion changes from deflation to inflation at the transition from moduli domination to thermal inflation. We analytically calculate the evolution of perturbations from moduli domination through thermal inflation and evaluate the curvature perturbation on the constant radiation density hypersurface at the end of thermal inflation to determine the late time curvature perturbation. Our resulting transfer function suppresses the power spectrum by a factor $\\sim 50$ at $k \\gg k_\\mathrm{b}$, with $k_\\mathrm{b}$ corresponding to anywhere from megaparsec to subparsec scal...

  17. Properties of small-scale magnetism of stellar atmospheres

    Science.gov (United States)

    Steiner, Oskar; Salhab, René; Freytag, Bernd; Rajaguru, Paul; Schaffenberger, Werner; Steffen, Matthias

    2014-12-01

    The magnetic field outside of sunspots is concentrated in the intergranular space, where it forms a delicate filigree of bright ribbons and dots as seen on broad band images of the Sun. We expect this small-scale magnetic field to exhibit a similar behavior in stellar atmospheres. In order to find out more about it, we perform numerical simulations of the surface layers of stellar atmospheres. Here, we report on preliminary results from simulations in the range between 4000 K and 6500 K effective temperature with an initial vertical, homogeneous magnetic field of 50 G strength. We find that the field strength of the strongest magnetic flux concentrations increases with decreasing effective temperature at the height level where the average Rosseland optical depth is one. On the other hand, at the same level, the field is less strong than the thermal equipartition value in the coolest model but assumes superequipartition in the models hotter than 5000 K. While the Wilson depression of the strongest field concentrations is about one pressure scale height in the coolest model, it is more than four times the pressure scale height in the hottest one. We also find that the relative contribution of the bright filigree to the bolometric, vertically directed radiative intensity is most significant for the Teff = 5000 K model (0.6%-0.79%) and least significant for the hottest and coolest models (0.1%-0.46% and 0.14%-0.32%, respectively). This behavior suggests that the effect of the small-scale magnetic field on the photometric variability is more significant for K dwarf stars than for F-type and also M-type stars.

  18. Large and small scale structures as sources of solar wind.

    Science.gov (United States)

    Poletto, Giannina

    In the past century, recurrent magnetic activity observed at Earth used to be ascribed to "streams" of particles flowing from unknown solar sources, that, after Bartels' suggestion (1932), were dubbed "M-regions". Through successive steps the search for these elusive sources eventu-ally ended up, about 40 years later, with the identification of M-regions as Coronal Holes (CHs): large-scale magnetically open areas, covering about 15However, it did not take long to realize that these regions, assumed to be unipolar, hosted also mized polarity areas and smaller struc-tures such as bright points and plumes, with typical sizes on the order of 1 arcmin., whose role had to be ascertained: does solar wind emanate from the ambient large-scale CH or from the small-scale features within it? While this debate is still going on, HINODE observations with unprecedented high spatial and temporal resolution,revealed even smaller CH substructures. X-ray jets, with a size as small as 1/10th of the above mentioned small-scale features, turned out to be ubiquitous in CHs and much more numerous than anticipated. Jets are definitely correlated to plumes, possibly preceding their formation, and once more we face the problem of understanding whether these tiny events have a role in the wind acceleration and mass loading. This talk describes the subsequently smaller features identified in CHs and illustrates how they contributed to our understanding of the solar wind origin and maintenance. "In situ" data, possibly related to coronal structures, are also shortly reviewed.

  19. Emissions from small scale combustion of pelletized wood fuels

    International Nuclear Information System (INIS)

    Combustion of wood pellets in small scale heating systems with an effect below 20 kW has increased. During the winter season 1995/96 1500 small plants for heating houses are estimated to be in operation. Stack emissions from three pellet burners and two pellet stoves have been studied at laboratory. Different pellet qualities were tested. When the fraction of fines increased also the NOx emissions increased with about 10 %. As reference fuel 8 mm pellets was used. Tests with 6 mm pellets gave, in most cases, significant lower emissions of CO and THC. Eleven stoves, burners and boilers were studied in a field test. The results show that all the plants generally have higher emissions in the field than during conditions when the plants are adjusted with a stack gas monitoring instrument. A conclusion is that it is difficult for the operator to adjust the plant without a monitoring instrument. The emissions from the tested plants give an estimation of stack gas emissions from small scale pellet plants. The difference between the 'best' and 'worst' technologies is big. The span of emissions with the best technology to the worst is given below. The interval is concerning normal combustion . During abnormal conditions the emissions are on a significant higher level: * CO 80-1 000 mg/MJ; * Tar 0,3-19 mg/MJ; * THC (as methane equivalents) 2-100 mg/MJ; * NOx 50-70 mg/W;, and * Dust emissions 20-40 mg/MJ. Emissions from pellets heating are lower than from wfrom pellets heating are lower than from wood combustion and the best technology is close to the emission from oil burners. Wood and pellets have the same origin but the conditions to burn them in an environmental friendly way differ. Combustion of pellets could be improved through improved control of the air and fuel ratio that will create more stable conditions for the combustion

  20. A Survey of Mining and Tailings Disposal Practices of Selected Artisanal and Small Scale Mining Companies in Ghana

    Directory of Open Access Journals (Sweden)

    Chiri G. Amedjoe

    2015-02-01

    Full Text Available Management of small scale mining operations for maximum profitability with good environmental stewardship requires careful planning of mining and tailings disposal strategies. Field studies and observations of eleven selected artisanal and small-scale gold mining companies winning gold from alluvial (placer source mostly, but also mine out cropping and underground quartz veins where available from the Takwaian and Birimian Formations in southwestern Ghana. Excavation is either by pitting or using backhoes. Sluicing, panning followed by mercury amalgamation and then roasting to recover the gold is the beneficiation method in use. Riverine waste rocks/tailings disposal is the main management invoked, however some companies do sell their waste to construction firms. Environmentally mining operations are impacting rivers with siltation, mercury pollution, channel diversions and possibly change in heavy metals concentration and water chemistry. Vast arable lands are degraded leaving peasant farmers with no livelihood due to failure by concessionaires to reclaim lands after closure. Only two companies out of the eleven somehow demonstrated environmental consciousness by constructing small tailings dam and backfilling some pits.

  1. Small-scale production of straight vegetable oil from rapeseed and its use as biofuel in the Spanish territory

    International Nuclear Information System (INIS)

    Biofuels nowadays are an important topic of study. The most significant point is the availability of bioethanol or biodiesel and their production from different raw materials. It is already known that large-scale production of first-generation biodiesel cannot be seen as an alternative to fossil fuels due to land requirements, competition with food, increase in fertilizer requirements and pressure on tropical forests among others. This fact does not necessarily apply to second-generation biofuels or small-scale niche productions. Straight vegetable oil (SVO) can be used directly in diesel engines with minor modifications. Our proposal is a small-scale SVO production system for self-supply in agricultural machinery. In this paper a model to provide SVO to local farmers in a specific area in Catalonia (Spain) is presented. We also present a discussion about the regulations to be changed in order to make possible the incorporation of SVO as engine fuel in diesel vehicles and a comparative analysis between the emissions of tractors fed with SVO and petrodiesel. Moreover, a quantitative economic analysis of modifying diesel engines and long-term operability costs are shown and a first-run economic analysis comparing the actual crop rotation with the proposed one and some alternatives is studied.

  2. 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)

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

    2012-01-01

    Full Text Available 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 i [...] n 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 the 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.

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

    Directory of Open Access Journals (Sweden)

    Théodore Munyuli

    2011-08-01

    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

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

    DEFF Research Database (Denmark)

    Mgeni, Dotto; Henningsen, Arne

    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.

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

    Directory of Open Access Journals (Sweden)

    ELTO EUGENIO GOMES E GAMA

    2004-04-01

    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.

  6. Harvesting next to poverty. An analysis of the cotton industry´s impact on small scale farmers in Zambia

    OpenAIRE

    Pedersen, Cecilie Toudal

    2009-01-01

    Et ofte stillet spørgsmål i udviklingssammenhænge er: hvordan fjerner vi fattigdom i verden? Der har i den forbindelse været en intensiv diskussion om sammenhængen mellem den handelsrelaterede økonomiske vækst og fattigdom (Dollar 2002, Rodrik 2007, Stiglitz 2006). Hvordan påvirker den økonomiske vækst i én sektor uligheden og fattigdomsniveauet i samfundet? Ud af denne diskussion er det kommet frem, at vækst i forskellige sektorer påvirker fattigdomsniveauet forskelligt (Bigsten 2008:1). Hvo...

  7. EFFICIENCY OF RESOURCE USE IN SMALL-SCALE WHITE SHRIMP (PENAEUS VANNAMEI PRODUCTION IN LAMONGAN REGENCY, EAST JAVA PROVINCE, INDONESIA

    Directory of Open Access Journals (Sweden)

    Riski A. Lestariadi

    2012-09-01

    Full Text Available This study carried out to determine the efficiency of recourses use in white shrimp (Penaeus Vannamei production in Lamongan Regency, East Java Province, Indonesia. The simple random sampling technique used to select 125 small-scale white shrimp farmers from six-study areas in Lamongan Regency. The white shrimp production function was estimated using Ordinary Least Square (OLS technique. The results indicated that Double Log production function had the best fit in explaining the relationship between output of white shrimp and inputs used. The coefficient of determination (R2 = 0.846 indicated that the eighty-four point six percent of variation in output of white shrimp was explained by the independent variables in the model. Findings showed that labor, fertilizer, feed and stocking density are significant determinants of production inputs. Moreover, the estimates of the ratio of the value of marginal product (VMP to marginal factor cost (MFC revealed that the non-optimal combination of inputs among the white shrimp farmers, it showed that the aquaculture farms resources were inefficiently utilized for labor, feed and stocking density by 1.94, 1.93 and 171.4 respectively, while fertilizer showed otherwise by 0.11 or over utilized.

  8. EFFICIENCY OF RESOURCE USE IN SMALL-SCALE WHITE SHRIMP (PENAEUS VANNAMEI PRODUCTION IN LAMONGAN REGENCY, EAST JAVA PROVINCE, INDONESIA

    Directory of Open Access Journals (Sweden)

    Riski A. Lestariad

    2012-01-01

    Full Text Available This study carried out to determine the efficiency of recourses used in white shrimp (Pe-naeus Vannamei production in Lamongan Regency, East Java Province, Indonesia. The simple random sampling technique used to select 125 small-scale white shrimp farmers from six-study areas in Lamongan Regency. The white shrimp production function was es-timated using Ordinary Least Square (OLS technique. The results indicated that Double Log production function had the best fit in explaining the relationship between output of white shrimp and inputs used. The coefficient of determination (R2 = 0.846 indicated that the eighty-four point six percent of variation in output of white shrimp was explained by the independent variables in the model. Findings showed that labor, fertilizer, feed and stocking density are significant determinants of production inputs. Moreover, the estimates of the ra-tio of the value of marginal product (VMP to marginal factor cost (MFC revealed that the non-optimal combination of inputs among the white shrimp farmers, it showed that the aq-uaculture farms resources were inefficiently utilized for labor, feed and stocking density by 1.94, 1.93 and 171.4 respectively, while fertilizer showed otherwise by 0.11 or over uti-lized.

  9. Small-Scale Irregularities in Equatorial Spread-F

    Science.gov (United States)

    Dimant, Yakov; Oppenheim, Meers

    2014-10-01

    Equatorial Spread-F is a spectacular plasma phenomenon that reshapes the nighttime ionosphere and disrupts GPS navigation and radio communication. Current computer models simulate the evolution of large-scale spread-F phenomena (1000km-to-kilometer), but they do not explain what causes the meter-scale irregularities observed by radars and space-borne instruments. Our recent particle-in-cell (PIC) simulations of weakly collisional plasma have demonstrated that large-scale plasma density gradients and related electric fields may drive local plasma instabilities, although only for a limited set of parameters. Motivated by these PIC simulations, we have revisited the linear theory of this instability, employing a novel and sophisticated eigenmode analysis. This method identified eigenmode wave structures in regions having strong plasma density gradients. These wave structures are not linearly unstable, but are not damped either. This means that small-scale fluctuations provided by an external source (e.g., by a nonlinear spectral cascade from longer-wavelength spread-F turbulence) can be resonantly amplified and may explain radar observations without invoking linear instability. Equatorial Spread-F is a spectacular plasma phenomenon that reshapes the nighttime ionosphere and disrupts GPS navigation and radio communication. Current computer models simulate the evolution of large-scale spread-F phenomena (1000km-to-kilometer), but they do not explain what causes the meter-scale irregularities observed by radars and space-borne instruments. Our recent particle-in-cell (PIC) simulations of weakly collisional plasma have demonstrated that large-scale plasma density gradients and related electric fields may drive local plasma instabilities, although only for a limited set of parameters. Motivated by these PIC simulations, we have revisited the linear theory of this instability, employing a novel and sophisticated eigenmode analysis. This method identified eigenmode wave structures in regions having strong plasma density gradients. These wave structures are not linearly unstable, but are not damped either. This means that small-scale fluctuations provided by an external source (e.g., by a nonlinear spectral cascade from longer-wavelength spread-F turbulence) can be resonantly amplified and may explain radar observations without invoking linear instability. Work supported by NASA LWS Grant 10-LWSTRT10-0078.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-08-01

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

  11. 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 USMall-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)

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

    DEFF Research Database (Denmark)

    Sohoni, Sujata Vijay; Bapat, Prashant Madhusudan

    2012-01-01

    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.

  13. Europe's first farmers

    Science.gov (United States)

    American Association for the Advancement of Science (AAAS; )

    2005-11-10

    People migrating from the Middle East brought farming techniques to present-day Germany and other parts of central Europe about 7,500 years ago. For years, scientists have been arguing over whether people with European ancestors are closely related to these first farmers. Some scientists say yes. Others say no and argue instead that people with European roots are closely related to the humans who lived in Europe long before the first farmers showed up.

  14. Small scale flow processes in aqueous heterogeneous porous media

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-04-01

    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.

  15. Small-scale inviscid accretion discs around black holes

    CERN Document Server

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

    2000-01-01

    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...

  16. Dynamic properties of small-scale solar wind plasma fluctuations.

    Science.gov (United States)

    Riazantseva, M O; Budaev, V P; Zelenyi, L M; Zastenker, G N; Pavlos, G P; Safrankova, J; Nemecek, Z; Prech, L; Nemec, F

    2015-05-13

    The paper presents the latest results of the studies of small-scale fluctuations in a turbulent flow of solar wind (SW) using measurements with extremely high temporal resolution (up to 0.03?s) of the bright monitor of SW (BMSW) plasma spectrometer operating on astrophysical SPECTR-R spacecraft at distances up to 350?000?km from the Earth. The spectra of SW ion flux fluctuations in the range of scales between 0.03 and 100?s are systematically analysed. The difference of slopes in low- and high-frequency parts of spectra and the frequency of the break point between these two characteristic slopes was analysed for different conditions in the SW. The statistical properties of the SW ion flux fluctuations were thoroughly analysed on scales less than 10?s. A high level of intermittency is demonstrated. The extended self-similarity of SW ion flux turbulent flow is constantly observed. The approximation of non-Gaussian probability distribution function of ion flux fluctuations by the Tsallis statistics shows the non-extensive character of SW fluctuations. Statistical characteristics of ion flux fluctuations are compared with the predictions of a log-Poisson model. The log-Poisson parametrization of the structure function scaling has shown that well-defined filament-like plasma structures are, as a rule, observed in the turbulent SW flows. PMID:25848078

  17. Latent hardening size effect in small-scale plasticity

    International Nuclear Information System (INIS)

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

  18. Statistics of small scale vortex filaments in turbulence

    CERN Document Server

    Biferale, Luca; Toschi, Federico

    2009-01-01

    We study the statistical properties of coherent, small-scales, filamentary-like structures in Turbulence. In order to follow in time such complex spatial structures, we integrate Lagrangian and Eulerian measurements by seeding the flow with light particles. We show that light particles preferentially concentrate in small filamentary regions of high persistent vorticity (vortex filaments). We measure the fractal dimension of the attracting set and the probability that two particles do not separate for long time lapses. We fortify the signal-to-noise ratio by exploiting multi-particles correlations on the dynamics of bunches of particles. In doing that, we are able to give a first quantitative estimation of the vortex-filaments life-times, showing the presence of events as long as the integral correlation time. The same technique introduced here could be used in experiments as long as one is capable to track clouds of bubbles in turbulence for a relatively long period of time, at high Reynolds numbers; shading ...

  19. Shaping mobile belts by small-scale convection.

    Science.gov (United States)

    Faccenna, Claudio; Becker, Thorsten W

    2010-06-01

    Mobile belts are long-lived deformation zones composed of an ensemble of crustal fragments, distributed over hundreds of kilometres inside continental convergent margins. The Mediterranean represents a remarkable example of this tectonic setting: the region hosts a diffuse boundary between the Nubia and Eurasia plates comprised of a mosaic of microplates that move and deform independently from the overall plate convergence. Surface expressions of Mediterranean tectonics include deep, subsiding backarc basins, intraplate plateaux and uplifting orogenic belts. Although the kinematics of the area are now fairly well defined, the dynamical origins of many of these active features are controversial and usually attributed to crustal and lithospheric interactions. However, the effects of mantle convection, well established for continental interiors, should be particularly relevant in a mobile belt, and modelling may constrain important parameters such as slab coherence and lithospheric strength. Here we compute global mantle flow on the basis of recent, high-resolution seismic tomography to investigate the role of buoyancy-driven and plate-motion-induced mantle circulation for the Mediterranean. We show that mantle flow provides an explanation for much of the observed dynamic topography and microplate motion in the region. More generally, vigorous small-scale convection in the uppermost mantle may also underpin other complex mobile belts such as the North American Cordillera or the Himalayan-Tibetan collision zone. PMID:20520711

  20. Analytic study of small scale structure on cosmic strings

    International Nuclear Information System (INIS)

    The properties of string networks at scales well below the horizon are poorly understood, but they enter critically into many observables. We argue that in some regimes, stretching will be the only relevant process governing the evolution. In this case, the string two-point function is determined up to normalization: the fractal dimension approaches one at short distance, but the rate of approach is characterized by an exponent that plays an essential role in network properties. The smoothness at short distance implies, for example, that cosmic string lensing images are almost undistorted. We then add in loop production as a perturbation and find that it diverges at small scales. This need not invalidate the stretching model, since the loop production occurs in localized regions, but it implies a complicated fragmentation process. Our ability to model this process is limited, but we argue that loop production peaks a few orders of magnitude below the horizon scale, without the inclusion of gravitational radiation. We find agreement with some features of simulations, and interesting discrepancies that must be resolved by future work

  1. Numerical Simulation of a Small-Scale Mild Combustor

    International Nuclear Information System (INIS)

    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.

  2. Numerical Simulation of a Small-Scale Mild Combustor

    Science.gov (United States)

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

    2012-11-01

    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.

  3. Development of a small-scale computer cluster

    Science.gov (United States)

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

    2008-04-01

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

  4. Small scale chromospheric jets above a sunspot light bridge

    CERN Document Server

    Louis, Rohan E; Ichimoto, Kiyoshi

    2014-01-01

    High-resolution broad-band filtergrams of active region NOAA 11271 in Ca ii H and G-band were obtained with the Solar Optical Telescope on board Hinode to identify the physical driver responsible for the dynamic and small-scale chromospheric jets above a sunspot light bridge. We identified the jets in the Ca images using a semi-automatic routine. The chromospheric jets consist of a bright, triangular-shaped blob that lies on the light bridge, while the apex of this blob extends into a spike-like structure which is bright against the dark umbral background. The majority of the jets have apparent lengths of less than 1000 km and about 30% of them have lengths between 1000-1600 km. They are oriented within +/-35 deg. to the normal of the light bridge axis. A majority of them are clustered near the central part within a 2 arcsec wide area. The jets are seen to move rapidly along the light bridge and a majority of them cannot be identified in successive images taken with a 2 min cadence. The jets are primarily loc...

  5. Small Scale Turbopump Manufacturing Technology and Material Processes

    Science.gov (United States)

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

    2011-01-01

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

  6. Small-scale swirl events in the quiet Sun chromosphere

    CERN Document Server

    Wedemeyer-Böhm, Sven

    2009-01-01

    Recent progress in instrumentation enables solar observations with high resolution simultaneous in the spatial, temporal, and spectral domains. We use such high-resolution observations to study small-scale structures and dynamics in the chromosphere of the quiet Sun. We analyze time series of spectral scans through the Ca II 854.2nm 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. The line core maps exhibit relatively few fibrils as compared to what is normally observed in quiet Sun regions outside coronal holes. The time series show a chaotic and dynamic scene that include 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 on the order of only 0.2", which is close to the effective spatial resolution. They exhibit Doppler shifts of -2 to -4 km/s ...

  7. Small Scale Clustering of Late Forming Dark Matter

    CERN Document Server

    Agarwal, Shankar; Das, Subinoy; Rasera, Yann

    2014-01-01

    We perform a study of the non-linear clustering of matter in the Late Forming Dark Matter (LFDM) scenario in which dark matter results from the transition of non-minimally coupled scalar field from radiation to collisionless matter. A distinct feature of this model is the presence of a damped oscillatory cut-off in the linear matter power spectrum at small scales. We use a suite of high-resolution N-body simulations to study the imprints of LFDM on the non-linear matter power spectrum, the halo mass function and the halo density profiles. The model satisfies high-redshift matter power spectrum constraints from Lyman-$\\alpha$ forest measurements. We find suppressed abundance of low mass halos ($\\sim 10^{9}-10^{10}$ h$^{-1}$ M$_\\odot$) at all redshifts compared to a vanilla $\\Lambda$CDM model. Furthermore, in this mass range we find significant deviations with respect to predictions from the Sheth-Tormen mass function. Halos with mass $M\\gtrsim 10^{11}$ h$^{-1}$ M$_\\odot$ show minor departures of the density pr...

  8. Calvin’s election mix in small-scale theology

    Directory of Open Access Journals (Sweden)

    James A. Loader

    2009-11-01

    Full Text Available This paper shows how Calvin’s ideas about the Old Testament concept of Israel’s election can be dangerous when they are applied uncritically. The main illustration material is drawn from a context the author was himself part of, notably the South African apartheid theology of Calvinist provenance. The paper begins with documenting Calvin’s views on Israel and Israel’s election in the Old Testament, moving to a consideration of how this motif was connected to the idea of predestination and construed to become an instrument to defend apartheid in what may be called a substandard theology. It is suggested that a glance at the English-speaking world shows surprising similarities that justify further consideration. In this title several dimensions are present that need to be explicated.

    How to cite this article: Loader, J.A., 2009, ‘Calvin’s election mix in small-scale theology’, HTS Teologiese Studies/Theological Studies 65(1, Art. #337, 6 pages. DOI: 10.4102/hts.v65i1.337

  9. Efficient small-scale dynamo in solar convection zone

    CERN Document Server

    Hotta, H; Yokoyama, T

    2015-01-01

    We investigate small-scale dynamo action in the solar convection zone through a series of high resolution MHD simulations in a local Cartesian domain with 1$R_\\odot$ (solar radius) of horizontal extent and a radial extent from 0.715 to 0.96$R_\\odot$. The dependence of the solution on resolution and diffusivity is studied. For a grid spacing of less than 350 km, the root mean square magnetic field strength near the base of the convection zone reaches 95% of the equipartition field strength (i.e. magnetic and kinetic energy are comparable). For these solutions the Lorentz force feedback on the convection velocity is found to be significant. The velocity near the base of the convection zone is reduced to 50% of the hydrodynamic one. In spite of a significant decrease of the convection velocity, the reduction in the enthalpy flux is relatively small, since the magnetic field also suppresses the horizontal mixing of the entropy between up- and downflow regions. This effect increases the amplitude of the entropy pe...

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

    Directory of Open Access Journals (Sweden)

    Oboro, O. G.

    2011-12-01

    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.

  11. Small-Scale Spray Releases: Orifice Plugging Test Results

    Energy Technology Data Exchange (ETDEWEB)

    Mahoney, Lenna A.; Gauglitz, Phillip A.; Blanchard, Jeremy; Kimura, Marcia L.; Kurath, Dean E.

    2012-09-01

    One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities, is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations published in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials present in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty introduced by extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches in which the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are largely absent. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine the aerosol release fractions and aerosol generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of anti-foam agents (AFA) was assessed with most of the simulants. Orifices included round holes and rectangular slots. Much of the testing was conducted at pressures of 200 and 380 psi, but some tests were conducted at 100 psi. Testing the largest postulated breaches was deemed impractical because of the large size of some of the WTP equipment. The purpose of the study described in this report is to provide experimental data for the first key technical area, potential plugging of small breaches, by performing small-scale tests with a range of orifice sizes and orientations representative of the WTP conditions. The simulants used were chosen to represent the range of process stream properties in the WTP. Testing conducted after the plugging tests in the small- and large-scale test stands addresses the second key technical area, aerosol generation. The results of the small-scale aerosol generation tests are included in Mahoney et al. 2012. The area of spray generation from large breaches is covered by large-scale testing in Schonewill et al. 2012.

  12. Small scale folding observed in the NEEM ice core

    Science.gov (United States)

    Jansen, Daniela; Llorens, Maria-Gema; Westhoff, Julien; Steinbach, Florian; Bons, Paul D.; Kipfstuhl, Sepp; Griera, Albert; Weikusat, Ilka

    2015-04-01

    Disturbances on the centimeter scale in the layering of the NEEM ice core (North Greenland) can be mapped by means of visual stratigraphy as long as the ice does have a visual layering, such as, for example, cloudy bands. Different focal depths of the visual stratigraphy method allow, to a certain extent, a three dimensional view of the structures. In this study we present a structural analysis of the visible folds, discuss characteristics and frequency and present examples of typical fold structures. With this study we aim to quantify the potential impact of small scale folding on the integrity of climate proxy data. We also analyze the structures with regard to the stress environment under which they formed. The structures evolve from gentle waves at about 1700 m to overturned z-folds with increasing depth. Occasionally, the folding causes significant thickening of layers. Their shape indicates that they are passive features and are probably not initiated by rheology differences between layers. Layering is heavily disturbed and tracing of single layers is no longer possible below a depth of 2160 m. Lattice orientation distributions for the corresponding core sections were analyzed where available in addition to visual stratigraphy. The data show axial-plane parallel strings of grains with c.axis orientations that deviate from that of the matrix, which has more or less a single-maximum fabric at the depth where the folding occurs. We conclude from these data that folding is a consequence of deformation along localized shear planes and kink bands. The findings are compared with results from other deep ice cores. The observations presented are supplemented by microstructural modeling using a crystal plasticity code that reproduces deformation, applying a Fast Fourier Transform (FFT), coupled with ELLE to include dynamic recrystallization processes. The model results reproduce the development of bands of grains with a tilted orientation relative to the single maximum fabric of the matrix and also the associated local deformation.

  13. Potential small-scale development of western oil shale

    Energy Technology Data Exchange (ETDEWEB)

    Smith, V.; Renk, R.; Nordin, J.; Chatwin, T.; Harnsberger, M.; Fahy, L.J.; Cha, C.Y.; Smith, E.; Robertson, R.

    1989-10-01

    Several studies have been undertaken in an effort to determine ways to enhance development of western oil shale under current market conditions for energy resources. This study includes a review of the commercial potential of western oil shale products and byproducts, a review of retorting processes, an economic evaluation of a small-scale commercial operation, and a description of the environmental requirements of such an operation. Shale oil used as a blend in conventional asphalt appears to have the most potential for entering today's market. Based on present prices for conventional petroleum, other products from oil shale do not appear competitive at this time or will require considerable marketing to establish a position in the marketplace. Other uses for oil shale and spent shale, such as for sulfur sorbtion, power generation, cement, aggregate, and soil stabilization, are limited economically by transportation costs. The three-state area area consisting of Colorado, Utah, and Wyoming seems reasonable for the entry of shale oil-blended asphalt into the commercial market. From a review of retorting technologies and the product characteristics from various retorting processes it was determined that the direct heating Paraho and inclined fluidized-bed processes produce a high proportion of heavy material with a high nitrogen content. The two processes are complementary in that they are each best suited to processing different size ranges of materials. An economic evaluation of a 2000-b/d shale oil facility shows that the operation is potentially viable, if the price obtained for the shale oil residue is in the top range of prices projected for this product. Environmental requirements for building and operating an oil shale processing facility are concerned with permitting, control of emissions and discharges, and monitoring. 62 refs., 6 figs., 10 tabs.

  14. Small-scale spatial structure in plankton distributions

    Directory of Open Access Journals (Sweden)

    A. Tzella

    2007-01-01

    Full Text Available The observed filamental nature of plankton populations suggests that stirring plays an important role in determining their spatial structure. If diffusive mixing is neglected, the various interacting biological species within a fluid parcel are determined by the parcel time history. The induced spatial structure has been shown to be a result of competition between the time evolution of the biological processes involved and the stirring induced by the flow as measured, for example, by the rate of divergence of the distance of neighbouring fluid parcels. In the work presented here we examine a simple biological model based on delay-differential equations, previously seen in Abraham (1998, including nutrients, phytoplankton and zooplankton, coupled to a strain flow. Previous theoretical investigations made on a differential equation model (Hernández-Garcia et al., 2002 imply that the latter two should share the same small-scale structure. The generalisation from differential equations to delay-differential equations, associated with the addition of a maturation time to the zooplankton growth, should not make a difference, provided sufficiently small spatial scales are considered. However, this theoretical prediction is in contradiction with the results of Abraham (1998, where the phytoplankton and zooplankton structures remain uncorrelated at all length scales. A new set of numerical experiments is performed here which show that these two regimes coexist. On larger scales, there is a decoupling of the spatial structure of the zooplankton distribution on the one hand, and the phytoplankton and nutrient on the other. On the other hand, at small enough length scales, the phytoplankton and zooplankton share the same spatial structure as expected by the theory involving no maturation time.

  15. Small-scale spatial structure in plankton distributions

    Directory of Open Access Journals (Sweden)

    A. Tzella

    2006-12-01

    Full Text Available The observed filamental nature of plankton populations suggests that stirring plays an important role in determining their spatial structure. If diffusive mixing is neglected, the various interacting biological species within a fluid parcel are determined by the parcel time history. The induced spatial structure has been shown to be a result of competition between the time evolution of the biological processes involved and the stirring induced by the flow as measured, for example, by the rate of divergence of the distance of neighbouring fluid parcels. In the work presented here we examine a simple biological model based on delay-differential equations, previously seen in Abraham (1998 including nutrients, phytoplankton and zooplankton, coupled to a strain flow. Previous theoretical investigations made on a differential equation model (Hernández-Garcia et al., 2002 imply that the latter two should share the same small-scale structure. The generalization from differential equations to delay-differential equations, associated with the addition of a maturation time to the zooplankton growth, should not make a difference, provided sufficiently small spatial scales are considered. However, this theoretical prediction is in contradiction with the results of Abraham (1998 where the phytoplankton and zooplankton structures remain uncorrelated at all length scales. A new set of numerical experiments is performed here which show that these two regimes coexist. On larger scales , there is a decoupling of the spatial structure of the zooplankton distribution on the one hand, and the phytoplankton and nutrient on the other. On the other hand, at small enough length scales, the phytoplankton and zooplankton share the same spatial structure as expected by the theory involving no maturation time.

  16. Stability of small-scale baryon perturbations during cosmological recombination

    Science.gov (United States)

    Venumadhav, Tejaswi; Hirata, Christopher

    2015-06-01

    In this paper, we study small-scale fluctuations (baryon pressure sound waves) in the baryon fluid during recombination. In particular, we look at their evolution in the presence of relative velocities between baryons and photons on large scales (k ˜1 0-1 Mpc-1 ), which are naturally present during the era of decoupling. Previous work concluded that the fluctuations grow due to an instability of sound waves in a recombining plasma, but that the growth factor is small for typical cosmological models. These analyses model recombination in an inhomogenous universe as a perturbation to the parameters of the homogenous solution. We show that for relevant wave numbers k ?1 03 Mpc-1 the dynamics are significantly altered by the transport of both ionizing continuum (h ? >13.6 eV ) and Lyman-? photons between crests and troughs of the density perturbations. We solve the radiative transfer of photons in both these frequency ranges and incorporate the results in a perturbed three-level atom model. We conclude that the instability persists at intermediate scales. We use the results to estimate a distribution of growth rates in 1 07 random realizations of large-scale relative velocities. Our results indicate that there is no appreciable growth; out of these 1 07 realizations, the maximum growth factor we find is less than ?1.2 at wave numbers of k ?1 03 Mpc-1 . The instability's low growth factors are due to the relatively short duration of the recombination epoch during which the electrons and photons are coupled.

  17. Thermalhydraulic analysis of small-scale tube rupture experiments

    International Nuclear Information System (INIS)

    Guillotine failure of a rupturing pressure tube is an accident situation currently being investigated in the safety analysis of CANDU reactors. One of the reasons for initiating the investigation was to determine the major factors controlling the onset of guillotine failure. As part of this program, small-scale rupture tests using fuel sheaths have been performed and numerically simulated. The fluid dynamic aspects of rupturing fuel sheaths simulated with a multi-dimensional prototype of the two-fluid thermalhydraulic code CATHENA are described in this paper. The results of the numerical simulations were examined by observing the behaviour of pressure transients of the fluid inside the tube during the rupture. A parametric study was first performed to determine optimum model conditions for two-dimensional simulations. Results from CATHENA simulations using these conditions were then compared with experimental data. Calculations were also extended to a three-dimensional thermalhydraulic analysis. This paper describes the results of the parametric and comparative studies. The effect of varying the simulation conditions on calculated pressure transients is also described. Although agreement between simulated results and experimental data was found to be good, some discrepancies were noted and are discussed. Advantages and disadvantages of the three-dimensional study are also presented. This investigation has been successful in demonstrating a method that can be used to emonstrating a method that can be used to enhance the understanding of the behaviour of pressure-tube rupture under accident conditions. Areas in which the numerical analysis could be advanced to further the understanding of rupturing pressure tubes are provided. 3 refs., 11 figs., 2 tabs

  18. Small-Scale Forest Ownership across Europe: Characteristics and Future Potential

    OpenAIRE

    Wiersum, K.F.; Elands, B.H.M.; Hoogstra, M.A.

    2005-01-01

    The concept of small-scale forest ownership means different things to different people in different countries. Traditionally, within Europe, many small-scale forest owners were economically dependent on their forests, either for home or commercial use, usually linked with farming activities. However, many small-scale forest owners are no longer economically dependent on their forests and these owners appear to increasingly focus their management on amenity functions rather than on production ...

  19. An Investigation of Innovation in Small Scale Industries Located in Science Parks of Iran

    OpenAIRE

    Alireza Fazlzadeh; Mostafa Moshiri

    2010-01-01

    In recent decades with increasing of global economic competition, small scale industries have known as aneconomic growth engine and a tool for employment so they have important role in growth and development ofcountries. The importance small scale industries of is its need more investment for their survival and competitioncapability than big firms to new products and processes. Therefore, small scale industries are a potential resourcefor achieving new ideas and innovation. Previous studies o...

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

    OpenAIRE

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

    2011-01-01

    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 ...

  1. On the effect of small-scale oceanic variability on topography-generated currents

    OpenAIRE

    Alvarez, Alberto; Hernandez-garcia, Emilio; Tintore, Joaquin

    2000-01-01

    Small-scale oceanic motions, in combination with bottom topography, induce mean large-scale along-isobaths flows. The direction of these mean flows is usually found to be anticyclonic (cyclonic) over bumps (depressions). Here we employ a quasigeostrophic model to show that the current direction of these topographically induced large-scale flows can be reversed by the small-scale variability. This result addresses the existence of a new bulk effect from the small-scale activi...

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

    International Nuclear Information System (INIS)

    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)

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

    Science.gov (United States)

    Kleeorin, Nathan; Rogachevskii, Igor

    2012-07-01

    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, \\lambda \\propto \\ln \\left ({Rm} / {Rm}^{ { cr}}\\right ) , 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.

  4. Visualization of small scale structures on high resolution DEMs

    Science.gov (United States)

    Kokalj, Žiga; Zakšek, Klemen; Pehani, Peter; ?otar, Klemen; Oštir, Krištof

    2015-04-01

    Knowledge on the terrain morphology is very important for observation of numerous processes and events and digital elevation models are therefore one of the most important datasets in geographic analyses. Furthermore, recognition of natural and anthropogenic microrelief structures, which can be observed on detailed terrain models derived from aerial laser scanning (lidar) or structure-from-motion photogrammetry, is of paramount importance in many applications. In this paper we thus examine and evaluate methods of raster lidar data visualization for the determination (recognition) of microrelief features and present a series of strategies to assist selecting the preferred visualization of choice for structures of various shapes and sizes, set in varied landscapes. Often the answer is not definite and more frequently a combination of techniques has to be used to map a very diverse landscape. Researchers can only very recently benefit from free software for calculation of advanced visualization techniques. These tools are often difficult to understand, have numerous options that confuse the user, or require and produce non-standard data formats, because they were written for specific purposes. We therefore designed the Relief Visualization Toolbox (RVT) as a free, easy-to-use, standalone application to create visualisations from high-resolution digital elevation data. It is tailored for the very beginners in relief interpretation, but it can also be used by more advanced users in data processing and geographic information systems. It offers a range of techniques, such as simple hillshading and its derivatives, slope gradient, trend removal, positive and negative openness, sky-view factor, and anisotropic sky-view factor. All included methods have been proven to be effective for detection of small scale features and the default settings are optimised to accomplish this task. However, the usability of the tool goes beyond computation for visualization purposes, as sky-view factor, for example, is an essential variable in many fields, e.g. in meteorology. RVT produces two types of results: 1) the original files have a full range of values and are intended for further analyses in geographic information systems, 2) the simplified versions are histogram stretched for visualization purposes and saved as 8-bit GeoTIFF files. This means that they can be explored in non-GIS software, e.g. with simple picture viewers, which is essential when a larger community of non-specialists needs to be considered, e.g. in public collaborative projects. The tool recognizes all frequently used single band raster formats and supports elevation raster file data conversion.

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

    Science.gov (United States)

    Aldas, Rizaldo Elauria

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Barrio, Maria

    2002-05-01

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

  7. Small-scale Geothermal Power Plants Using Hot Spring Water

    Science.gov (United States)

    Tosha, T.; Osato, K.; Kiuchi, T.; Miida, H.; Okumura, T.; Nakashima, H.

    2013-12-01

    The installed capacity of the geothermal power plants has been summed up to be about 515MW in Japan. However, the electricity generated by the geothermal resources only contributes to 0.2% of the whole electricity supply. After the catastrophic earthquake and tsunami devastated the Pacific coast of north-eastern Japan on Friday, March 11, 2011, the Japanese government is encouraging the increase of the renewable energy supply including the geothermal. It needs, however, more than 10 years to construct the geothermal power plant with more than 10MW capacity since the commencement of the development. Adding the problem of the long lead time, high temperature fluid is mainly observed in the national parks and the high quality of the geothermal resources is limited. On the other hand hot springs are often found. The utilisation of the low temperature hot water becomes worthy of notice. The low temperature hot water is traditionally used for bathing and there are many hot springs in Japan. Some of the springs have enough temperature and enthalpy to turn the geothermal turbine but a new technology of the binary power generation makes the lower temp fluid to generate electricity. Large power generators with the binary technology are already installed in many geothermal fields in the world. In the recent days small-scale geothermal binary generators with several tens to hundreds kW capacity are developed, which are originally used by the waste heat energy in an iron factory and so on. The newly developed binary unit is compact suitable for the installation in a Japanese inn but there are the restrictions for the temperature of the hot water and the working fluid. The binary power unit using alternatives for chlorofluorocarbon as the working fluid is relatively free from the restriction. KOBELCO, a company of the Kobe Steel Group, designed and developed the binary power unit with an alternative for chlorofluorocarbon. The unit has a 70 MW class electric generator. Three units have been installed in Obama Hot Spring area, Nagasaki Prefecture, where about 15,000 tonnes of hot water are produced in a day and more than 35% of the hot water flow directly to the sea. Another demonstration experiments are also conducted in several hot spring areas. In this study we will review several examples to utilise low temperature hot springs in Japan. Binary Power Unit at Obama (Fujino, 2013)

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

    Directory of Open Access Journals (Sweden)

    Agomuo Florence Ozioma

    2012-03-01

    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.

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

    Directory of Open Access Journals (Sweden)

    Orisakwe Lambert

    2012-06-01

    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.

  10. Beyond the field : Impact of Farmer Field Schools on food security and poverty alleviation

    DEFF Research Database (Denmark)

    LilleØr, Helene Bie; Larsen, Anna Folke

    2013-01-01

    In this paper, we estimate the impact of a farmer field school intervention among small scale farmers in Northers Tanzania. Unlike previous farmer field school evaluations, we go beyond the immediate agricultural impact and estimate the impact of farmer field school participation in the pre-specified development objects, namely poverty alleviation and food security among participating households. We wxploit the implementation design of a gradual project roll-out to establish a quasi-experimental difference-in-difference setup, which can account for potential selection info the project, both at village and household level, despite the lack of baseline data. we find strong positive effects on measures of food security, but we find no effect on the poverty indicators. We investigate possible mechanisms for this and conclude that both reallocation of labor ressources and improved production smoothing among participation households may, in part, lead to this finding.

  11. Cosmological Origin of Small-Scale Clumps and DM Annihilation Signal

    CERN Document Server

    Berezinsky, Vladimir; Eroshenko, Y N; Berezinsky, Veniamin; Dokuchaev, Vyacheslav; Eroshenko, Yury

    2004-01-01

    We study the cosmological origin of small-scale DM clumps in the hierarchical scenario with the most conservative assumption of adiabatic Gaussian fluctuations. The mass spectrum of small-scale clumps with M10^6 Msun is very small.

  12. FarmLime manual: for small-scale production of agricultural lime

    OpenAIRE

    Mitchell, C. J.; Mwanza, M.

    2005-01-01

    This manual is a concise guide to the small-scale production of agricultural lime. It was developed as part of a research project, ‘Low-cost lime for small-scale farming’ otherwise known as FarmLime (Mitchell, CJ, 2005). The ideal agricultural lime is a ground dolomite or dolomitic limestone with a particle size of 100%

  13. 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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-05-29

    One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and net generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of antifoam agents was assessed with most of the simulants. Orifices included round holes and rectangular slots. For the combination of both test stands, the round holes ranged in size from 0.2 to 4.46 mm. The slots ranged from (width × length) 0.3 × 5 to 2.74 × 76.2 mm. Most slots were oriented longitudinally along the pipe, but some were oriented circumferentially. In addition, a limited number of multi-hole test pieces were tested in an attempt to assess the impact of a more complex breach. Much of the testing was conducted at pressures of 200 and 380 psi, but some tests were conducted at 100 psi. Testing the largest postulated breaches was deemed impractical because of the much larger flow rates and equipment that would be required. This report presents the experimental results and analyses for the aerosol measurements obtained in the small-scale test stand. It includes a description of the simulants used and their properties, equipment and operations, data analysis methodologies, and test results. The results of tests investigating the role of slurry particles in plugging small breaches are reported in Mahoney et al. (2012). The results of the aerosol measurements in the large-scale test stand are reported in Schonewill et al. (2012) along with an analysis of the combined results from both test scales.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-11-01

    One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of anti-foam agents was assessed with most of the simulants. Orifices included round holes and rectangular slots. The round holes ranged in size from 0.2 to 4.46 mm. The slots ranged from (width × length) 0.3 × 5 to 2.74 × 76.2 mm. Most slots were oriented longitudinally along the pipe, but some were oriented circumferentially. In addition, a limited number of multi-hole test pieces were tested in an attempt to assess the impact of a more complex breach. Much of the testing was conducted at pressures of 200 and 380 psi, but some tests were conducted at 100 psi. Testing the largest postulated breaches was deemed impractical because of the large size of some of the WTP equipment. This report presents the experimental results and analyses for the aerosol measurements obtained in the small-scale test stand. It includes a description of the simulants used and their properties, equipment and operations, data analysis methodologies, and test results. The results of tests investigating the role of slurry particles in plugging small breaches are reported in Mahoney et al. (2012). The results of the aerosol measurements in the large-scale test stand are reported in Schonewill et al. (2012) along with an analysis of the combined results from both test scales.

  16. Beyond the field : Impact of Farmer Field Schools on food security and poverty

    DEFF Research Database (Denmark)

    Larsen, Anna Folke; LilleØr, Helene Bie

    2014-01-01

    We estimate the impact of a Farmer Field School intervention among small-scale farmers in northern Tanzania on two main development objectives: food security and poverty. We employ a series of evaluation methodologies, including a Quasi-Difference-in-Difference setup, to account for potential selection into the project, despite lack of baseline data. We find strong positive effects on food security, but no effect on poverty. Investigating possible mechanisms for this result shows that reallocation of labor resources toward own agricultural production and improved production smoothing may have led to improved food security while poverty remained unaffected.

  17. Healthy Mouth, Healthy Body

    Science.gov (United States)

    ... 137http://jada.ada.org April 2006 563 Healthy mouth, healthy body T he mouth is a window into the health of the ... Sjögren’s syndrome—may first become apparent because of mouth lesions or other oral problems. The mouth is ...

  18. Small-scale hydroelectric power in the southeast: new impetus for an old energy source

    Energy Technology Data Exchange (ETDEWEB)

    1980-06-01

    The Southeastern conference, Small-Scale Hydroelectric Power: New Impetus for an Old Energy Source, was convened to provide a forum for state legislators and other interested persons to discuss the problems facing small-scale hydro developers, and to recommend appropriate solutions to resolve those problems. During the two-day meeting state legislators and their staffs, along with dam developers, utility and industry representatives, environmentalists and federal/state officials examined and discussed the problems impeding small-scale hydro development at the state level. Based upon the problem-oriented discussions, alternative policy options were recommended for consideration by the US Department of Energy, state legislatures and the staff of the National Conference of State Legislatures (NCSL). Emphasis was placed on the legal, institutional, environmental and economic barriers at the state level, as well as the federal delays associated with licensing small-scale hydro projects. Whereas other previously held conferences have emphasized the identification and technology of small-scale hydro as an alternative energy source, this conference stressed legislative resolution of the problems and delays in small-scale hydro licensing and development. Panel discussions and workshops are summarized. Papers on the environmental, economic, and legal aspects of small-scale hydropower development are presented. (LCL)

  19. Irrigation Practices, State Intervention and Farmers' Life- Worlds in Drought-Prone Tigray, Ethiopia

    OpenAIRE

    Teshome, W.

    2003-01-01

    This study examines irrigation practices, state intervention and the responses of farmers in theTigrayregion ofEthiopia. Although governments have been involved in the construction of irrigation infrastructures since the mid-1980s to mitigate drought and famine in many parts ofEthiopia, the responses of irrigators to such interventions have never been studied. The main concern of this study therefore is to document how irrigation intervention interfaces with the life-worlds of small-scale irr...

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

    Directory of Open Access Journals (Sweden)

    Ojenike

    2013-01-01

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-02-15

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

  2. Danish farmer’s perception of GM-crops

    DEFF Research Database (Denmark)

    SØndergaard, Janus; Pedersen, SØren Marcus

    2005-01-01

    This paper presents a study of 185 farmer’s perception of GM-crops in Denmark. The respondent’s attitude to GM-crops mainly reflects a conservative view of the adoption of GM-crops. Among farmers only the exciting crops in rotation is seen as their future potential GM-crops. Findings from this study show that more the 60 pct do not expect any or less than 13 EUR increase in gross margins on their farms from adopting GM-crops. This assessment illustrates that the farmers regard the GM-crops more as a way of ‘staying in business” than a technology to increase their profits.

  3. Regeneratively-Cooled, Turbopump-Fed, Small-Scale Cryogenic Rocket Engines Project

    National Aeronautics and Space Administration — To-date, the realization of small-scale, high-performance liquid bipropellant rocket engines has largely been limited by the inability to operate at high chamber...

  4. Small-scale production and use of wood fuels. Annual report 2007

    International Nuclear Information System (INIS)

    The 'Small-scale production and use of wood fuels' technology research programme is targeting to develop solutions which are economically competitive, reliable and acceptable in terms of emissions as regards small-scale (usually under 1 MW) wood fuel production, storage, processing, distribution and heat production. The programme aims to: 1. Develop technologies for the export market in the field of small-scale wood fuel production and use. 2. Strengthen the expertise of SMEs both in R and D and business operations. 3. Facilitate the networking of companies. 4. Improve international connections with similar companies and research institutes in order to exchange and boost specialist skills and knowledge.5. Enhance regional expertise through cooperation between the National Technology Agency and other operators. The programme supports the National Climate Strategy objective of developing competitive technological solutions to increase the small-scale use of wood by 45% by 2010

  5. Small scale hydroelectric power potential in Nevada: a preliminary reconnaissance survey

    Energy Technology Data Exchange (ETDEWEB)

    Cochran, G.F.; Fordham, J.W.; Richard, K.; Loux, R.

    1981-04-01

    This preliminary reconnaissance survey is intended to: develop a first estimate as to the potential number, location and characteristics of small-scale (50 kW to 15 MW) hydroelectric sites in Nevada; provide a compilation of various Federal and state laws and regulations, including tax and financing regulations, that affect small-scale hydroelectric development and provide information on sources of small-scale hydroelectric generation hardware and consultants/ contractors who do small scale hydroelectric work. The entire survey has been conducted in the office working with various available data bases. The site survey and site evaluation methods used are described, and data are tabulated on the flow, power potential, predicted capital expenditures required, etc. for 61 potential sites with measured flows and for 77 sites with derived flows. A map showing potential site locations is included. (LCL)

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

    Energy Technology Data Exchange (ETDEWEB)

    1980-07-01

    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.

  7. RELATIONSHIP BETWEEN PERSONALITY AND MOTIVATION FACTORS OF SMALL SCALE WOMEN ENTREPRENEURS

    Directory of Open Access Journals (Sweden)

    A.Kaviyarasan

    2015-06-01

    Full Text Available The present study made an attempt to find out the personality and motivation factors of small scale womenentre preneurs i n Nagapattinam district. The study tried to know whether there any influence of demographic variables on personality and motivation factors of small scale women entrepreneurs. In the present investigation a sample of 100 small scale women entrepreneurs were selected randomly. Primary data were collected from the respondents using questionnaire developed by researcher. After collecting the data, they were coded using Microsoft excel. The data were analyzed in Statistical Package for Social Science. Mean, Standard Deviation, t-test and One way ANOVA analysis were applied to test the hypotheses. Result shows that there is a significant difference between small scale women entrepreneurs differ in their personality and motivation factors.

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

    Directory of Open Access Journals (Sweden)

    Mumtaz Ali Junejo

    2008-09-01

    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.

  9. Tuberculosis: Getting Healthy, Staying Healthy

    Science.gov (United States)

    Tuberculosis Getting Healthy, Staying Healthy U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES National Institutes of Health National Institute of Allergy and Infectious Diseases Tuberculosis Getting Healthy, Staying Healthy U.S. DEPARTMENT OF HEALTH ...

  10. Marketing strategy for retailing small-scale wind energy turbines in Indian markets

    OpenAIRE

    Harjula, Nina

    2009-01-01

    The study analyzes the small-scale wind energy markets in Mumbai, focusing on questions: How feasible is the wind energy for SME businesses in Mumbai, and what are the main challenges and opportunities of small-scale wind energy in Mumbai? The study is a qualitative case study, in which, the data has been collected through observing the markets by visiting wind energy sites and companies, interviewing and meeting potential customers and other stakeholders in the market. Theoretical frame...

  11. Small scale energy release driven by supergranular flows on the quiet Sun

    OpenAIRE

    Potts, H. E.; Khan, J.; Diver, D.

    2007-01-01

    In this article we present data and modelling for the quiet Sun that strongly suggest a ubiquitous small-scale atmospheric heating mechanism that is driven solely by converging supergranular flows. A possible energy source for such events is the power transfer to the plasma via the work done on the magnetic field by photospheric convective flows, which exert drag of the footpoints of magnetic structures. In this paper we present evidence of small scale energy release events driven directl...

  12. Inclusion of small-scale milk producers in modern dairy value chains

    OpenAIRE

    Wouters, A. P.; Lee, J.

    2010-01-01

    The worldwide demand for milk is ever-increasing. The question we address here is how small-scale milk producers, mainly based in developing countries, can participate in modern dairy value chains? First, markets should have the preconditions of a reliable market, a competitive milk price and access to essential services and inputs. Second, small-scale producers need to improve farm management practices (feeding, breeding, control animal diseases) to become economically and environmentally mo...

  13. Evolution of Small Scale Cosmological Baryon Perturbations and Matter Transfer Functions

    OpenAIRE

    Yamamoto, Kazuhiro; Sugiyama, Naoshi; Sato, Humitaka

    1997-01-01

    The evolution of small scale cosmological perturbations is carefully re-examined. Through the interaction with photons via electrons, baryon perturbations show interesting behavior in some physical scales. Characteristic features of the evolution of baryon density fluctuations are discussed. In CDM models, it is found a power-law growing phase of the small-scale baryon density fluctuations, which is characterized by the terminal velocity, after the diffusion (Silk) damping a...

  14. On Spatial Resolution in Habitat Models: Can Small-scale Forest Structure Explain Capercaillie Numbers?

    OpenAIRE

    Ilse Storch

    2002-01-01

    This paper explores the effects of spatial resolution on the performance and applicability of habitat models in wildlife management and conservation. A Habitat Suitability Index (HSI) model for the Capercaillie (Tetrao urogallus) in the Bavarian Alps, Germany, is presented. The model was exclusively built on non-spatial, small-scale variables of forest structure and without any consideration of landscape patterns. The main goal was to assess whether a HSI model developed from small-scale habi...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-09-01

    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)

  16. Application of Heterogeneous Catalysis in Small-Scale Biomass Combustion Systems

    OpenAIRE

    Christian Thiel; Mirjam Matthes; Ingo Hartmann; Saad Butt; René Bindig

    2012-01-01

    Combustion of solid biomass fuels for heat generation is an important renewable energy resource. The major part among biomass combustion applications is being played by small-scale systems like wood log stoves and small wood pellet burners, which account for 75% of the overall biomass heat production. Despite an environmentally friendly use of renewable energies, incomplete combustion in small-scale systems can lead to the emission of environmental pollutants as well as substances which are h...

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

    OpenAIRE

    Yusuff Olabisi Sherifat

    2013-01-01

    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 significant...

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

    OpenAIRE

    AJIT ASHTE; ASWALE S. N.

    2013-01-01

    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, ...

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

    OpenAIRE

    Marian MIHAIU; Alexandra LAPUSAN; Romolica MIHAIU; Sorin D. DAN; Carmen JECAN

    2012-01-01

    Buffalo husbandry is an important source of income for a number of small-scale producers in Romania that is why an assessment of its? product?s quality is much needed for improvement and evaluation of their vulnerability to international competition. In order to ascertain possible developments in the buffalo dairy sector and to broadly identify areas of intervention that favor small-scale dairy producers, the study examined the potential to improve buffalo milk production by evaluating it...

  20. Measuring capacity and capacity utilization in small-scale fisheries in Nha Trang

    OpenAIRE

    Tang, Thi Hien

    2011-01-01

    To develop effective capacity management programs, it is significant to evaluate and control the fishing capacity and its utilization in order to reduce overcapacity and excess capacity and create a stable development of marine resources. This study estimate fishing capacity and capacity utilization (CU) for the multi-species small- scale trawlers in Nha Trang, Vietnam. Data were collected through a survey of 65 small-scale trawler owners in two years 2005 and 2006. Using a mathematical progr...

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

    OpenAIRE

    Ojenike; Joseph Olusola; Olowoniyi; Adeyemi Olusola

    2013-01-01

    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 ava...

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

    OpenAIRE

    Kuranchie, Francis Atta

    2011-01-01

    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 for these businesses to have a productive and economical operation that will ensure their sustainability. In this study, the potential of energy efficiency measures for micro and small scale busin...

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

    OpenAIRE

    Margaret Njeri Gathura

    2013-01-01

    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...

  4. Analysis of Labour Supply & Use in Small Scale Farming In Ikwuano/Umuahia L.G.A. of Abia State, Nigeria

    Directory of Open Access Journals (Sweden)

    Jonah, Ikoku John

    2014-04-01

    Full Text Available This study examines the supply and utilisation of labour resources among farmers in Ikwuano-Umuahia Local Government Area of Abia State. A total of 175 small scale farmers were randomly selected and interviewed with the use of structured questionnaires in five out of the nine autonomous communities that make up the local government area. The data collected were analysed and the results showed that average family labour force of 200 man days was not enough to cultivate the average farm size of 2.158 hectares. Labour shortage exists. Farmers are making up for this shortage by using communal and hired labour. Each farmer uses on the average 48.0 mandays of communal labour and 222.24 mandays of hired labour in order to cultivate the average farm size. Shortage of farm labour was found to be due to increasing rate of migration of rural labour force to the urban centres, non-farm employment, non-availability of saving technologies e.g. fertilizers etc.. A labour demand function was estimated against the following independent variables: Wage rate, farm size ,cost of capital, cost of other inputs, family labour in mandays, communal labour and hired labour in mandays. The result showed that farm size, family labour, communal labour and hired labour were all significant while the other independent variables though not significant, have signs which agree with economic theory. Based on the findings of the analysis, some recommendations were made namely reducing drastically the rate of migration of rural labour force by embarking on rural development projects, provision of labour saving technologies.

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

    DEFF Research Database (Denmark)

    JØnsson, Jesper Bosse; Fold, Niels

    2009-01-01

    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.

  6. Ethnographic Approaches to Understanding Social Sustainability in Small-scale Water Systems

    Science.gov (United States)

    Wutich, A.

    2011-12-01

    Social sustainability is an important, but often neglected, aspect of determining the success of small-scale water systems. This paper reviews ethnographic approaches for understanding how indigenous knowledge enhances social sustainability of small-scale water systems, particularly in small-scale water systems threatened by water scarcity. After reviewing the literature on common-pool and traditional resource management strategies, the paper will focus on the case of a community-managed small-scale water system in Cochabamba, Bolivia. This study uses ethnographic evidence to demonstrate how indigenous institutions can be used to manage a small-scale urban water system sustainably. Several factors were crucial to the institution's success. First, indigenous residents had previous experience with common management of rural irrigation systems which they were able to adapt for use in an urban environment. Second, institutional rules were designed to prioritize the conservation of the water source. Third, indigenous Andean social values of uniformity, regularity, and transparency ensured that community members perceived the system as legitimate and complied with community rules. Fourth, self-governance enabled community members to quickly adapt to changing environmental conditions, such as seasonal scarcity and groundwater overdraft. The paper concludes with a discussion of the promise and limitations of ethnographic approaches and indigenous knowledge for understanding social sustainability in small-scale water systems.

  7. 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

  8. Occupational hearing loss in farmers.

    OpenAIRE

    Plakke, B L; Dare, E

    1992-01-01

    Studies have shown that there is a great deal of high-frequency sensorineural hearing loss among farmers. The studies have failed, however, to differentiate farmers who have occupational noise exposure only from other potential hearing loss etiologies. This study, through extensive case history information, has isolated a farm noise-exposure group and matched its members by age with persons with no significant noise exposure. Results indicate that farmers exposed only to noise from farming ha...

  9. Climate Kids: Farmer's Market Manager

    Science.gov (United States)

    In this career-oriented interview, readers are introduced to the manager of several farmer's markets in Portland, Oregon. Following a brief description of his job and the general operations of a farmer’s market, he explains why these venues are beneficial to the vendors, the customers and the environment. The Climate Kids website is a NASA education resource featuring articles, videos, images and games focused on the science of climate change.

  10. Ways of removal of legislative and regulatory contradictions in sphere of small-scale business state administration

    Directory of Open Access Journals (Sweden)

    Mytnyk, Ulyana Mykolayivna

    2011-11-01

    Full Text Available Author investigated the problems of small-scale business state administration. The legislative and regulatory basis which regulates the small-scale business management was considered in the article. Legislative and regulatory contradictions were revealed in sphere of small-scale business state administration. The ways of removal of the conflictness were offered.

  11. An Appraisal of Farmer Variety Selection in Drought Prone Areas and Its Implication to Breeding for Drought Tolerance

    Directory of Open Access Journals (Sweden)

    Xavier Mhike

    2012-04-01

    Full Text Available Maize production and productivity among small scale farmers of southern Africa is limited mainly by drought and low soil fertility. This study aimed at assessing how farmers prioritize selection of varieties for planting under drought stress and how this could help improve the breeding approaches for varieties for resource constrained farmers in marginal environments. A survey was conducted in two drought prone districts of Zimbabwe. Data collection was done using a structured questionnaire, key informant interviews and focus group discussions. The study revealed that farmers have limited options for drought tolerant varieties available on the market. Contrary to breeders, farmers in drought prone areas do not consider disease resistance as an important trait. The farmer preferred traits include, high yield potential, drought tolerance, early maturity, and good performance even under poor soil conditions. Drought tolerance associated traits such as resistance to leaf rolling, tassel blast, general plant recovery to stress and stay green characteristics were identified as the most important traits but most of the varieties currently available on the market do not have these traits. The farmers were willing to make trade-offs among traits like taste or disease resistance for increased yield potential when selecting varieties to grow. Traits preferences or ranking and possible trade-offs were specific to specific areas and groups of farmers. In this study farmers still planted the traditional varieties or landraces because they are drought tolerant, taste better and can be propagated from farm saved seed. These findings show that farmers have limited options on drought tolerant varieties on the market and that scientists need to tap into farmer knowledge, especially on possible trade offs, trait ranking and germplasm for use in developing better adapted varieties which are specific to target farmers. Policies and seed systems analysis on variety availability, distribution and marketing channels also need to be strengthened.

  12. The combined effect of plate motions and small-scale convection on mantle stirring efficiency

    Science.gov (United States)

    samuel, H.; King, S. D.

    2013-12-01

    The Earth's mantle convection generates large scale, vigorous motions often thought to be the primary mechanism of mantle mixing. However, additional thermal instabilities may progressively develop below the lithospheric plates, leading to smaller scale convective motions. While there is a growing body of evidence supporting the presence of small-scale convective motions in the Earth's mantle, little is known about its contribution to the stirring of mantle heterogeneities. We therefore investigated the influence of small-scale convection on mantle stirring efficiency using numerical models of infinite Prandtl number convection with imposed surface ridge motion. We measured stirring efficiency using Finite Time Lyapunov Exponents, and we systematically varied the aspect ratio of the convective domain, and the plate Péclet number, Pe, which expresses the ridge half-spreading rate. For moderate Pe numbers, small-scale convection is well developed. However, at larger Pe numbers the development of small-scale convection is gradually inhibited. Mantle motion is closely related to its stirring efficiency. The coupled contribution of small scale convection and plate-driven flow to the efficiency of stirring leads to a non-monotone relationship between ridge spreading rates and mantle stirring efficiency, a more complex relationship than previously considered. Stirring efficiency first decreases with increasing ridge spreading rate until small-scale convection ceases completely. Beyond this point, a further increase in ridge spreading rate progressively enhances stirring efficiency via pure plate-driven flow. Our results indicate that: (i) both small scale convection and large scale flow contribute significantly to mantle stirring efficiency, (ii) mantle stirring efficiency may spatially vary significantly due to the local magnitude of plate velocity and plate age, (iii) the relationship between mantle stirring efficiency and large scale convective motions may be more complex than previously thought. These experiments provide an alternative to the interpretation of MORB isotopic variability, and may reconcile the apparent discrepancy of slow spreading ridges associated with small isotopic variability, as observed, for example, along the South West Indian Ridge.

  13. Technology Awareness and Farmers Perception in Adoption of Wheat Production Technologies: Case Study in Njoro and Rongai Divisions

    International Nuclear Information System (INIS)

    Wheat is the second most important cereal crop in Kenya but its production has not been able to meet high demand, since production is only fifty percent. The shortfall is supplemented by importation. The purpose of this study was to assess and describe farmers' perception on adoption of wheat production technologies in Njoro and Rongai divisions. One hundred and fifty (150) wheat farmers were randomly selected using stratified proportional random sampling technique. The data was analysed using descriptive and inferential statistics. farmers perception in wheat production is favourable with 80.2% agreeing that it access to credits by farmers. This was only possible to 7.3% of the farmers. above 90% of the farmers in the two divisions exist. Farmers' perception for small-scale 3.25% as higher than 2.75% for large-scale wheat farmers with t-test-2.21 at ?=0.05 for pest and disease control.s Education level and farm size significantly affected adoption, while gender and age were not significant

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

    Directory of Open Access Journals (Sweden)

    A. Higuchi

    2010-12-01

    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.

  15. Healthy Living

    Science.gov (United States)

    ... changes to your lifestyle. By taking steps toward healthy living, you can help reduce your risk of ... Get the screening tests you need Maintain a healthy weight Eat a variety of healthy foods, and ...

  16. Combine Effects of Plate Motions and Small-Scale Convection on Mantle Stirring Efficiency

    Science.gov (United States)

    King, S.; Samuel, H.

    2012-04-01

    Convection in Earth's mantle generates large scale, vigorous motions often thought to be the primary mechanism of mantle stirring. However additional thermal instabilities may progressively develop below lithospheric plates, leading to smaller scale convective motions. While there is growing evidence supporting the presence of small-scale convection in Earth's mantle, little is known of its contribution to the mixing of mantle heterogeneities. We have thus investigated the influence of small-scale convection on mantle stirring efficiency using 2D numerical modeling of infinite Prandtl number convection with imposed surface plate motion and temperature and pressure dependent rheology. We measure stirring efficiency using Finite Time Lyapunov Exponents (FTLE) and we vary systematically the Peclet number, Pe, defined as the ratio of the advection time scale based on surface plate velocity to a characteristic diffusion time. Our computational domain has an aspect ratio of 1:3. For moderate Pe, small-scale convection is well developed, leading to efficient stirring. However large Pe numbers do not allow the development of small-scale convection and result in significantly lower stirring efficiency, although plate motions are faster. This indicates that (i) small-scale convection contributes significantly to mantle stirring efficiency, (ii) mantle stirring efficiency many spatially vary significantly due to the local magnitude of plate velocity and (iii) the relationship between mantle stirring efficiency and large-scale convective motions may be more complex than previously thought.

  17. Small scale effects on the mechanical behaviors of protein microtubules based on the nonlocal elasticity theory

    International Nuclear Information System (INIS)

    Based on the nonlocal elastic theory, small scale effects are considered in the investigation of the mechanical properties of protein microtubules. A new prediction formula for the persistence lengths of microtubules with the consideration of the small scale effect is presented. Subsequently, the buckling of microtubules is studied based on a nonlocal elastic beam model. The predicted results of our model indicate that the length-dependence of persistence length is related not only to the shear terms, but also to the small scale effect. The Eular beam model, which is always considered unable to explain the length-dependence of microtubules, can capture the length-dependence of the persistence length of microtubules with the consideration of the small scale effect. The elastic buckling behaviors of microtubules in viscoelastic surrounding cytoplasm are also considered using the nonlocal Timoshenko beam model in this paper, and the results indicate that the small scale effect of microtubules also plays an important role in the buckling of microtubules.

  18. Is the small-scale magnetic field correlated with the dynamo cycle?

    CERN Document Server

    Karak, Bidya Binay

    2015-01-01

    The small-scale magnetic field is ubiquitous at the solar surface---even at high latitudes. From observations we know that this field is uncorrelated (or perhaps even weakly anticorrelated) with the global sunspot cycle. Our aim is to explore the origin, and particularly the cycle dependence of this field using three-dimensional dynamo simulations. We use a simple model of a turbulent dynamo in a shearing box driven by helically forced turbulence. Depending on the dynamo parameters, large-scale (global) and small-scale (local) dynamos can be excited independently in this model. Based on simulations in different parameter regimes, we find that, when only the large-scale dynamo is operating in the system, the small-scale magnetic field generated through shredding and tangling of the large-scale magnetic field is positively correlated with the global magnetic cycle. However, when both dynamos are operating, the small-scale field is produced from both the small-scale dynamo and the tangling of the large-scale fie...

  19. IMPACT OF SOCIO-ECONOMIC FACTORS ON THE PERFORMANCE OF SMALL-SCALE ENTERPRISES IN OSUN STATE, NIGERIA

    Directory of Open Access Journals (Sweden)

    Abdul-azeez ibraheem adegoke

    2010-03-01

    Full Text Available This study examined the impact of socio-economic characteristics on the performance of small-scale enterprises in the study area. It also identified the salient impacts of socio-economic traits on the development and expansion of small-scale enterprises in the country; established the productive prospects of progressive small-scale enterprises in the study area. The study was carried out in Osogbo, Osun State, Nigeria where copies of structured questionnaire were purposively administered on selected respondents. Evidence from the study shows that socio-economic characteristics of small scale entrepreneurs tend to influence the performance and productivity of Small Scale Enterprises in Nigeria.Further analysis shows that gender, age and educational qualification had significant influence on the performance of the selected small-scale enterprises in the study area . The paper suggests integrated approach to the development of individual entrepreneurial capacity and promotion of sustainable small-scale enterprises.

  20. An Investigation of Challenges Facing Home Gardening Farmers in South Africa: A Case Study of Three Villages in Nkokonbe Municipality Eastern Cape Province

    Directory of Open Access Journals (Sweden)

    Ogundiran Oluwasola Adekunle

    2013-12-01

    Full Text Available This paper therefore addresses the challenges facing the home garden farmers in Eastern Cape Province of South Africa. Sixty households farmer were selected through systematic sampling from Nkokonbe municipality which were purposively selected. The small scale farmers were interviewed with the help of an interview schedule containing open and closed ended questions. Data were analysed using descriptive statistics with the help of Statistical Package for Social Sciences (SPSS. The results revealed that small scale farmers in Eastern Cape Province lack awareness of improved agricultural practices and technical knowhow because the extension staffs to farmer ratio is high. Results further reveals that they also lacked finance, experienced high interest rates on credit facilities and uncertainty of the right seed to use due to flooding of the market by many seed companies. In view of the research findings, several policy proposals are suggested. These include ensuring the availability of market information to all farmers, capacitating smallholder farmers with production and financial management skills and extension support service.

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

    Energy Technology Data Exchange (ETDEWEB)

    Buxton, Abbi

    2013-02-15

    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.

  2. Irreversibility and small-scale generation in 3D turbulent flows

    CERN Document Server

    Pumir, Alain; Grauer, Rainer; Bodenschatz, Eberhard

    2015-01-01

    In three-dimensional turbulent flows energy is supplied at large scales and cascades down to the smallest scales where viscosity dominates. The flux of energy through scales implies the generation of small scales from larger ones, which is the fundamental reason for the irreversibility of the dynamics of turbulent flows. As we showed recently, this irreversibility manifests itself by an asymmetry of the probability distribution of the instantaneous power $p$ of the forces acting on fluid elements. In particular, the third moment of $p$ was found to be negative. Yet, a physical connection between the irreversibility manifested in the distribution of $p$ and the energy flux or small-scale generation in turbulence has not been established. Here, with analytical calculations and support from numerical simulations of fully developed turbulence, we connect the asymmetry in the power distribution, {\\it i.e.}, the negative value of $\\langle p^3 \\rangle$, to the generation of small scales, or more precisely, to the am...

  3. Generation of large-scale magnetic fields by small-scale dynamo in shear flows

    CERN Document Server

    Squire, Jonathan

    2015-01-01

    We propose a new mechanism for turbulent mean-field dynamo in which the magnetic fluctuations resulting from a small-scale dynamo drive the generation of large-scale magnetic fields. This is in stark contrast to the common idea that small-scale magnetic fields should be harmful to large-scale dynamo action. These dynamos occur in the presence of large-scale velocity shear and do not require net helicity, resulting from off-diagonal components of the turbulent resistivity tensor as the magnetic analogue of the "shear-current" effect. Given the inevitable existence of non-helical small-scale magnetic fields in turbulent plasmas, as well as the generic nature of velocity shear, the suggested mechanism may help to explain generation of large-scale magnetic fields across a wide range of astrophysical objects.

  4. EMERGENCE OF THE KENNICUTT-SCHMIDT RELATION FROM THE SMALL-SCALE SFR-DENSITY RELATION

    International Nuclear Information System (INIS)

    We use simulations of isolated galaxies with a few parsec resolution to explore the connection between the small-scale star formation rate (SFR)-gas density relation and the induced large-scale correlation between the SFR surface density and the surface density of the molecular gas (the Kennicutt-Schmidt relation). We find that, in the simulations, a power-law small-scale ''star formation law'' directly translates into an identical power-law Kennicutt-Schmidt relation. If this conclusion holds in the reality as well, it implies that the observed approximately linear Kennicutt-Schmidt relation must reflect the approximately linear small-scale ''star formation law''.

  5. SCION: CubeSat Mission Concept to Observe Midlatitude Small-Scale Irregularities and Scintillation

    Science.gov (United States)

    Heine, T.; Moldwin, M.

    2014-12-01

    The SCintillation and Ionospheric Occultation NanoSats (SCION) mission concept is to deploy two low-cost CubeSat spacecraft that maintain a separation distance <1 km to measure scintillation and associated small-scale density irregularities in the midlatitude ionosphere. Each spacecraft is equipped with a dual frequency GPS receiver to measure total electron content (TEC) and the S4 scintillation index along raypaths from the receiver to the GPS constellation. Scintillation causing small-scale density irregularities are increasingly observed in the vicinity of large TEC gradients associated with storm enhanced density (SED) regions. Detection of irregularities of the scale that cause GPS and VHF scintillation has previously relied on assumptions about their structural stability and drift speed. Space-based, multipoint observations would provide broad, regional coverage and disambiguation of temporal and spatial density fluctuations in order to detect small-scale irregularities without these assumptions.

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

    Directory of Open Access Journals (Sweden)

    Li Ming

    2013-03-01

    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.

  7. Air emissions of small-scale (< 10 MW) biomass boilers. Review of three field tests

    International Nuclear Information System (INIS)

    Objectives of greenhouse gases emission reduction, which encourages bio-energy development for heat purposes, are compatible with air-quality policies if the concept of clean biomass combustion is applied. This paper presents actual emission levels of atmospheric pollutants of small-scale (2, NOx, fine particulate matters, metallic compounds. Installation design (power, flue-gas cleaning techno logy) also has a major impact on organic pollutants and fine particulate matter emissions. A large majority of boilers have very low emission levels. Guidelines are finally stated to keep on promoting small-scale biomass boilers in order to be air-quality compatible and efficient to fight climate change. (author)

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

    DEFF Research Database (Denmark)

    Kristensen, Anders Kasper Bruun; Thomsen, Jane FrØlund

    2014-01-01

    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.

  9. A Survey of Small-scale Layer Production Systems in Botswana

    OpenAIRE

    S.S. Badubi; Ravindran, V.

    2004-01-01

    A questionnaire-based survey was conducted to investigate small-scale layer production systems in Botswana. The survey covered layer farms in the districts of Francistown and Letlhakane in the eastern part of Botswana, and examined aspects of productivity parameters, housing, management and diseases. The average hen day production in small-scale layer farms was 71.7% and the average daily feed intake was 108.1 g per hen. An average of 1 740 g feed was required to produce one dozen eggs. Hens ...

  10. Development of small-scale directly gas-fired integrated HVAC system

    International Nuclear Information System (INIS)

    A small-scale directly gas-fired integrated HVAC system is being investigated. The main principle is to use the waste heat of a CHP plant, possibly in conjunction with solar energy, for dehumidification of ambient air. Driving a small-scale absorption chiller is not feasible because of the high waste heat temperature required and the high cost of an absorption chiller. The required cooling capacity of the mechanically / electrically driven compression-type chiller is reduced drastically since no further dehumidification by condensation is necessary. In contrast to Desiccant Cooling Systems no water is required. (author)

  11. Informal Credit Markets and the Development of Micro and Small Scale Enterprises in Nigeria

    Directory of Open Access Journals (Sweden)

    Ojenike Joseph Ojenike

    2012-11-01

    Full Text Available This study analyzed the development in investment of Micro and Small Scale Enterprises Intermediated by theinformal credit market in Nigeria. Primary data for this study were collected from 10 (ten Local GovernmentAreas 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 smallscale enterprises. Policy aimed at making fund increasingly available to small scale enterprises is recommend toboost growth in small and micro enterprises.

  12. Running with BICEP2: Implications for Small-Scale Problems in CDM

    OpenAIRE

    Garrison-Kimmel, Shea; Horiuchi, Shunsaku; Abazajian, Kevork N.; Bullock, James S; Kaplinghat, Manoj

    2014-01-01

    The BICEP2 results, when interpreted as a gravitational wave signal and combined with other CMB data, suggest a roll-off in power towards small scales in the primordial matter power spectrum. Among the simplest possibilities is a running of the spectral index. Here we show that the preferred level of running alleviates small-scale issues within the $\\Lambda$CDM model, more so even than viable WDM models. We use cosmological zoom-in simulations of a Milky Way-size halo along ...

  13. Efficient Term Extraction and Indexing Approach in Small-Scale Web Search of Uyghur Language

    OpenAIRE

    Turdi Tohti; Winira Musajan; Askar Hamdulla

    2013-01-01

    In order to avoid the frequently read-write of hard disk and to speed up the search, the index should be saving in the memory in the small-scale web search. But, to express the original information by fewer memory spaces, also needs for index compression, and this would increases the computation expenses or brings certain harm to the original information in a way. In this research of Uyghur small-scale web search, in order to speed up the retrieval and query speed, inverted index has establis...

  14. Healthy shiftwork, healthy shiftworks.

    Science.gov (United States)

    Kogi, K

    2001-12-01

    Reflecting diversifying shift systems, extensive effort is put into managing shiftwork and reducing safety and health risks. It is accepted that shiftworkers are exposed to particular risks inherent in their irregular work schedules. This raises the question of how and to what extent we can ensure healthy work life for shiftworkers. In answering the question, we need to identify effective measures to improve both shiftworking conditions and the health of shiftworkers. Based on recent experiences in managing shiftwork, we note three directions of such measures: (a) comprehensive action to avoid risk-enhancing conditions based on general guidelines, (b) risk control as to workload, worksite ergonomics and risk reduction, and (c) support for flexible and restful working life. International standards are obviously relevant to these three aspects. Our own experiences in applying a set of ergonomic checkpoints to plant maintenance shiftwork demonstrate the usefulness of focusing on flexible work schedules and on multiple job-related factors such as night workload, ergonomic environment, resting conditions and training. There is a strong need for participatory planning and implementation of multi-area improvements as well as for relying on flexible schedules and autonomic teamwork. We may conclude that healthy shiftwork and healthy shiftworkers are compatible with each other only when certain conditions are met. In achieving this end, we need to combine (a) comprehensive measures to improve work schedules and job life, (b) strict risk management and (c) locally adjusted participatory steps for continual improvement. PMID:14564850

  15. Integrated Assessment of Artisanal and Small-Scale Gold Mining in Ghana - Part 3: Social Sciences and Economics.

    Science.gov (United States)

    Wilson, Mark L; Renne, Elisha; Roncoli, Carla; Agyei-Baffour, Peter; Tenkorang, Emmanuel Yamoah

    2015-07-01

    This article is one of three synthesis reports resulting from an integrated assessment (IA) of artisanal and small-scale gold mining (ASGM) in Ghana. Given the complexities that involve multiple drivers and diverse disciplines influencing ASGM, an IA framework was used to analyze economic, social, health, and environmental data and to co-develop evidence-based responses in collaboration with pertinent stakeholders. We look at both micro- and macro-economic processes surrounding ASGM, including causes, challenges, and consequences. At the micro-level, social and economic evidence suggests that the principal reasons whereby most people engage in ASGM involve "push" factors aimed at meeting livelihood goals. ASGM provides an important source of income for both proximate and distant communities, representing a means of survival for impoverished farmers as well as an engine for small business growth. However, miners and their families often end up in a "poverty trap" of low productivity and indebtedness, which reduce even further their economic options. At a macro level, Ghana's ASGM activities contribute significantly to the national economy even though they are sometimes operating illegally and at a disadvantage compared to large-scale industrial mining companies. Nevertheless, complex issues of land tenure, social stability, mining regulation and taxation, and environmental degradation undermine the viability and sustainability of ASGM as a livelihood strategy. Although more research is needed to understand these complex relationships, we point to key findings and insights from social science and economics research that can guide policies and actions aimed to address the unique challenges of ASGM in Ghana and elsewhere. PMID:26184277

  16. Proceedings of a workshop on agroforestry tree seeds for farmers

    DEFF Research Database (Denmark)

    LillesØ, Jens-Peter Barnekow

    2007-01-01

    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.

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

    Directory of Open Access Journals (Sweden)

    Margaret Njeri Gathura

    2013-09-01

    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.

  18. 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 ins in collaboration with local financial institutions and other market players. (author)

  19. 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)

  20. Nanoflares, Spicules, and Other Small-Scale Dynamic Phenomena on the Sun

    Science.gov (United States)

    Klimchuk, James

    2010-01-01

    There is abundant evidence of highly dynamic phenomena occurring on very small scales in the solar atmosphere. For example, the observed pr operties of many coronal loops can only be explained if the loops are bundles of unresolved strands that are heated impulsively by nanoflares. Type II spicules recently discovered by Hinode are an example of small-scale impulsive events occurring in the chromosphere. The exist ence of these and other small-scale phenomena is not surprising given the highly structured nature of the magnetic field that is revealed by photospheric observations. Dynamic phenomena also occur on much lar ger scales, including coronal jets, flares, and CMEs. It is tempting to suggest that these different phenomena are all closely related and represent a continuous distribution of sizes and energies. However, this is a dangerous over simplification in my opinion. While it is tru e that the phenomena all involve "magnetic reconnection" (the changin g of field line connectivity) in some form, how this occurs depends s trongly on the magnetic geometry. A nanoflare resulting from the interaction of tangled magnetic strands within a confined coronal loop is much different from a major flare occurring at the current sheet form ed when a CME rips open an active region. I will review the evidence for ubiquitous small-scale dynamic phenomena on the Sun and discuss wh y different phenomena are not all fundamentally the same.

  1. The Rural Landscapes and Small-Scale Agricultural Practices in the Transylvanian Plain

    Directory of Open Access Journals (Sweden)

    Nicolae BACIU

    2010-06-01

    Full Text Available This paper is focused on the relationships between small-scale agricultural practices and cultural landscape of Transylvanian Plain. The geographical position of Transylvanian Plain in central part of Romania shows with relevance its favourability for sustainable agriculture and developing assumptions. Despite of this, the region was kept outside of the major infrastructural and economic trends. We could, also, include the Transylvanian Plain into a typical rural “central isolation space” relating on this historical-political tendencies, concluding on different types of rural and agricultural landscapes. In this context, small-scale agriculture practices are alternatives to factory farming or more broadly, intensive agriculture or unsustainable farming methods. Sustainable agriculture is not only a package of prescribed methods but is a pre-requisite for territorial development of rural areas. Small scale agriculture include a number of sustainable farm practices such as: organic farming, which removes all chemical pesticides, herbicides and fertilizer from agriculture; permaculture, which provides a holistic methodology for farm design; arable land use that is used for growing crops; non-arable land use; pastoral land use etc. Generally speaking, the small-scale agricultural practices are oriented to: produce enough food; produce safe food; take care of the environment; build thriving and strong rural communities.

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

    Science.gov (United States)

    Migliaccio, Todd; Raskauskas, Juliana

    2013-01-01

    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…

  3. Fuel From Farms: A Guide to Small-Scale Ethanol Production.

    Science.gov (United States)

    Solar Energy Research Inst., Golden, CO.

    Ethanol and blends of ethanol and gasoline (such as gasohol) offer a near-term fuel alternative to oil. The focus of this handbook is upon the small-scale production of ethanol using farm crops as the source of raw materials. Provided are chapters on ethanol production procedures, feedstocks, plant design, and financial planning. Also presented…

  4. SOCIO ECONOMICS CONDITIONS OF INDUSTRIAL LABOURS IN SMALL SCALE INDUSTRIES A CASE STUDY OF RAICHUR DISTRICT

    OpenAIRE

    Jagadeesh

    2014-01-01

    At 1800, India had a significant presence in the world as a manufacturing country. Possibly about 15-20 per cent of its working population, or 15-20 million persons were employed in industry at that time. All of it was small-scale artisanal industry, and the great majority of the production units were family-labour oriented or 'households'.

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

    DEFF Research Database (Denmark)

    Wargocki, Pawel; Sabikova, J.

    2002-01-01

    Thirty-nine untrained subjects made small- and full-scale evaluations of the acceptability of the quality of air at 22 deg.C and 40% RH, polluted by either carpet, felt floor covering, painted gypsum board, linoleum or chipboard. Small-scale evaluations were made on the air extracted from 200-L 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.

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

    OpenAIRE

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

    2008-01-01

    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.

  7. Small scales formation via Alfven wave propagation in compressible nonuniform media

    Science.gov (United States)

    Malara, F.; Primavera, L.; Veltri, P.

    1995-01-01

    In weakly dissipative media governed by the magnetohydrodynamics (MHD) equations, any efficient mechanism of energy dissipation requires the formation of small scales. The possibility to produce small scales has been studied by Malara et al. in the case of MHD disturbances propagating in an incompressible and inhomogeneous medium, for a strictly 2D geometry. We extend the work of Malara et al. to include both compressibility and the third component for vector quantities. Using numerical simulations we show that, when an Alfven wave propagates in a compressible nonuniform medium, the two dynamical effects responsible for the small scales formation in the incompressible case are still at work: energy pinching and phase-mixing. Moreover, the interaction between the initial Alfven wave and the inhomogeneity gives rise to the formation of compressible perturbations (fast and slow waves or a static entropy wave). Some of these compressive fluctuations are subject to the steepening of the wave front and become shock waves, which are extremely efficient in dissipating their energy, their dissipation being independent of the Reynolds number. A rough estimate of the typical times which the various dynamical processes take to produce small scales and then to dissipate the energy show that these times are consistent with those required to dissipate inside the solar corona the energy of Alfven waves of photospheric origin.

  8. Small-scale dynamos on the solar surface: dependence on magnetic Prandtl number

    CERN Document Server

    Thaler, I

    2015-01-01

    The question of possible small-scale dynamo action in the surface layers of the Sun is revisited with realistic 3D MHD simulations. As in other MHD problems, dynamo action is found to be a sensitive function of the magnetic Prandtl number ${\\rm P_{\\rm m} }=\

  9. Auto Farmer Using Renewable Energy

    Directory of Open Access Journals (Sweden)

    TANAY CHOWDHURY

    2013-02-01

    Full Text Available AUTO FARMER is one of the mean machine project. In the world of increasing population the demand for increase in growth of the food increases, this demands greater productivity with greater quality. The aim of AUTO FARMER USING RENEWABLE ENERGY is to provide automation and create a imprint in the field of agriculture. Today the farming underwent many difficulties like depending on rain, the restless manual work and the efforts .

  10. Auto Farmer Using Renewable Energy

    OpenAIRE

    TANAY CHOWDHURY; DAYARAM GORA; VIKASH YADAV; A.R.SURYAWANSHI

    2013-01-01

    AUTO FARMER is one of the mean machine project. In the world of increasing population the demand for increase in growth of the food increases, this demands greater productivity with greater quality. The aim of AUTO FARMER USING RENEWABLE ENERGY is to provide automation and create a imprint in the field of agriculture. Today the farming underwent many difficulties like depending on rain, the restless manual work and the efforts .

  11. Low and High Potentials of Entrepreneurial Development within the Framework of Indigenious Small Scale Management in Africa

    Directory of Open Access Journals (Sweden)

    Olatunji Eniola Sule

    2013-05-01

    Full Text Available This work looked at the potentials of entrepreneurship development within the framework of indigenous small scale management. It also show those potentials that are inherent in entrepreneurs of small scale business both low and high potentials and possibly expose some of the problems or drawbacks of entrepreneur of small scale business in Africa. The writer try to show what small scale business is like and possibly other scholars’ assumptions of what small scale business is all about. Finally, some suggestions were proffered by the writer based on the personal experiences on how to enhance the potentials of entrepreneurs of small scale business in Nigeria and possibly, the entire continent of Africa; talking about how to cope with, both internal and external environmental forces of the business.

  12. Farmers' willingness to pay for less health risks by pesticide use: A case study from the cotton belt of Punjab, Pakistan.

    Science.gov (United States)

    Khan, Muhammad; Damalas, Christos A

    2015-10-15

    The amount of pesticides used in crop production in Pakistan has increased rapidly in the last decades, whereas farmers in many areas of the country show little knowledge of safe and efficient use of pesticides. The level of willingness to pay (WTP) for avoiding health risks by pesticides was studied among 318 randomly selected cotton farmers from two districts of the area of Punjab (i.e., Vehari and Lodhran) in Pakistan, using the contingent valuation method. Most farmers felt that pesticide use is a prerequisite for successful cotton production, whereas at the same time they were well aware of pesticide health risks, which they considered minor. The majority of the farmers (77%) showed varying levels of WTP some fee up to 20% of the current pesticide expenditures for avoiding pesticide health risks, but few were willing to pay a fee over 20%. The mean WTP per farmer was low, reaching 5.8 $US on an annual basis. By contrast, a considerable proportion of the farmers (23%) were not willing to pay any fee for avoiding pesticide health risks. These individuals were mostly poor small-scale farmers with limited or no education. High levels of risk perception about pesticides, past experience of pesticide intoxication, high levels of education, and high income were associated with high farmers' WTP for less health risks by pesticides. Farmers who perceived major health risks by pesticides appeared to be highly willing to pay a premium for safe pesticides. Elderly farmers appeared more likely to pay some premium for safe pesticides as a result of higher farming experience and higher income than young farmers. Well-educated farmers were more likely to pay a high premium for safe pesticides. Large farm size was a significant predictor of positive WTP, which was interpreted as an indicator of farmers' wealth. PMID:26047864

  13. 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)

    Justice G. Djokoto

    2012-02-01

    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.

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

    OpenAIRE

    Okoli, B. E.

    2011-01-01

    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 an...

  15. Soil Nutrient Content Influences the Abundance of Soil Microbes but Not Plant Biomass at the Small-Scale

    OpenAIRE

    Koorem, Kadri; Gazol, Antonio; O?pik, Maarja; Moora, Mari; Saks, U?lle; Uibopuu, Annika; So?ber, Virve; Zobel, Martin

    2014-01-01

    Small-scale heterogeneity of abiotic and biotic factors is expected to play a crucial role in species coexistence. It is known that plants are able to concentrate their root biomass into areas with high nutrient content and also acquire nutrients via symbiotic microorganisms such as arbuscular mycorrhizal (AM) fungi. At the same time, little is known about the small-scale distribution of soil nutrients, microbes and plant biomass occurring in the same area. We examined small-scale temporal an...

  16. Conversion of fracture toughness testing values from small scale three point bending test specimens to small scale yielding state (SSY) by elastic-plastic stress analysis

    International Nuclear Information System (INIS)

    The report describes the work performed for achieving readiness to calculate fracture toughness dependence on dimension effects and loading conditions in fracture test specimens and real structures. In the report two- and three-dimensional computer codes developed and calculational methods applied are described. One of the main goals is to converse fracture toughness from small scale three point bending test specimens to case of a depth crack in plane strain i.e. to small scale yielding state (SSY) by numerical elastic-plastic stress analysis. Thickness effect of a test specimens and effect of a crack depth are separately investigated. Tests of three point bending specimens with and without sidegrooves and curved crack front are numerically simulated and experimental and computed results are compared. J-integral is calculated along crack front and also from force-deflection dependence of the beam. For the analyses the computing system was thoroughly automatized. Measuring capacity of three point bending test specimens was tried to evaluate. (orig.) (7 refs., 54 figs.)

  17. 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.

  18. Development of small-scale peat production. Final report; Turpeen pientuotannon kehittaeminen. Loppuraportti

    Energy Technology Data Exchange (ETDEWEB)

    Erkkilae, A.; Kallio, E.; Paappanen, T.

    1998-12-31

    The objective of this three year project was to develop the production conditions, methods and technology of small-scale peat producers so that the profitability of small-scale peat production is improved and the competitiveness remains. The aim in 1996 was to determine the present situation of small-scale peat producers, and the research and development needs, as well as to prepare a development plan of the small-scale peat production. The aims for 1997 were: the diminishing of the environmental hazards and the run-off waters of the small-scale peat production, the intensification of the peat deliveries from small-scale peat production, and the reduction of the peat production costs by improving the degree of utilization of the equipment via common or shared use. According to the results of the study peat production in Finland in 1996 was 25.0 TWh in total. The share of milled peat was 91 % of the peat production, and that of sod peat 9.0 %. About 1 440 000 m{sup 3} of other than energy peat was produced. The share of energy peat producers, replying to the questionnaire was 13 % (3.3 TWh) and the share of other peat producers was 18 %. Peat was produced from the area of 59 000 ha, the share of small-scale peat producers was 9 250 ha corresponding to about 16 % of the total peat production area. The share of milled peat of the peat produced by small-scale peat producers was about 73 %. The number of peat produces replying to the questionnaire was 164. The level of water protection and other environmental protection of twelve peat producers in the Southern Ostrobothnia were studied. According to the survey the main shortages comprised too small or lacking settling ponds. Also other shortages in environmental protection were observed. Feedback on the survey, as well as guidance and suggestions for improvements were given to the producers. Deliveries of peat by the small-scale peat producers to the Rauhalahti power plant of Jyvaeskylaen Energiantuotanto Oy were reviewed in order to intensify the deliveries. By using new delivery regions it would be possible to reduce the number of lorries transporting the peat from the present 17 lorries to 9 lorries. The annual transportation amounts will be normalized and they would be increased from the present average of 53 000 m{sup 3} to 109 000 m{sup 3}. The value of reducing of the waiting times would be about 1.0 FIM/m{sup 3} calculated on the basis of the total peat deliveries to the plant. The shared usage of the transportation devices of the Haku method by several producers might in some cases be profitable method for replacing the own pneumatic harvesters of peat producers. Hence the common production area should be at least 50 - 100 ha. The engine-rents determination principles were reviewed in the study. In addition to this it was calculated that on the basis of long-term weather condition data it would be possible to produce 250 - 300 m{sup 3} of milled peat along with the sod peat production without interfering the sod peat production by using hired milled peat machines. The profitability of the production depends, however, on the rent determined on the basis of the total usage rate of milled peat production machinery

  19. Healthy Snacks

    Science.gov (United States)

    WGBH Educational Foundation

    2011-07-01

    This animated video segment adapted from the Centers for Disease Control and Prevention, featuring American Indian characters, offers suggestions of what to eat for healthy snacks and looks at why less healthy snacks should be considered sometimes foods.

  20. Healthy Eating

    Science.gov (United States)

    ... as for Sunday brunch. Continue Stock Up on Healthy Foods Kids, especially younger ones, will eat mostly ... meal. Make it easy for kids to choose healthy snacks by keeping fruits and vegetables on hand ...

  1. Healthy Sexuality

    Medline Plus

    Full Text Available ... important is that a sexual experience is safe, healthy, and enjoyable. Sexual health is a vital part ... a health care professional. Everyone can achieve the healthy and satisfying sex life that they deserve.

  2. Healthy Eyes

    Science.gov (United States)

    Healthy Vision Diabetes Diabetes Home How Much Do You Know? What You Should Know Protecting Against Vision ... de los Ojos Cómo hablarle a su oculista Healthy Eyes Listen Having a comprehensive dilated eye exam ...

  3. Comparison of Improved Sugarcane Genotypes on Farmer`s Field

    Directory of Open Access Journals (Sweden)

    Khan Bahadar

    2000-01-01

    Full Text Available Performance of five sugarcane varieties viz. Bannu-1, Naurang-98, COL-75, S-86-US-422 and PAS-132 was evaluated at 39 locations on farmer`s field in Bannu division for four consecutive years. The study revealed that varieties Bannu-1 and Naurang-98 out yielded other varieties during the entire period of investigation. However, amongst these, Naurang-98 exhibited better sugar recovery. Variety S-86-US-422 possessed higher sugar contents as compared to PAS-132 and COL-75. On the basis of results obtained, sugarcane varieties Bannu-1 and Naurang-98 were recommended for general cultivation in the area.

  4. Small-scale simulation of vapor discharges into subcooled liquid pools

    International Nuclear Information System (INIS)

    The methodology proposed by Sonin [Nucl. Eng. Des. 65 (1981) 17-21] for small-scale modeling of high-flux vapor discharges into subcooled pools is verified experimentally using sonic steam discharges into water. Small-scale simulation is used to show that the dynamic pressures induced by sonic steam discharges into water increase with decreasing subcooling when the subcooling is high, reach a maximum at a pool subcooling of 20-30 K or greater, and then decrease with further reductions in subcooling, becoming very low as the subcooling approaches zero. Condensation remains complete to very low subcooling. Data are presented for both straight pipe discharges and model devices simulating a BWR quencher. (orig.)

  5. Small-scale patterning methods for digital image correlation under scanning electron microscopy

    International Nuclear Information System (INIS)

    Digital image correlation (DIC) is a powerful, length-scale-independent methodology for examining full-field surface deformations. Recently, it has become possible to combine DIC with scanning electron microscopy (SEM), enabling the investigation of small-scale deformation mechanisms such as the strains accommodated within grains in polycrystalline metals, or around micro-scale constituents in composite materials. However, there exist significant challenges that need to be surmounted before the combination of DIC and SEM (here termed SEM-DIC) can be fully exploited. One of the primary challenges is the ability to pattern specimens at microstructural length scales with a random, isotropic and high contrast pattern needed for DIC. This paper provides a thorough survey of small-scale patterning methods for SEM-DIC and discusses their advantages and disadvantages for different applications

  6. Magnetic field tunable small-scale mechanical properties of nickel single crystals measured by nanoindentation technique.

    Science.gov (United States)

    Zhou, Hao; Pei, Yongmao; Fang, Daining

    2014-01-01

    Nano- and micromagnetic materials have been extensively employed in micro-functional devices. However, measuring small-scale mechanical and magnetomechanical properties is challenging, which restricts the design of new products and the performance of smart devices. A new magnetomechanical nanoindentation technique is developed and tested on a nickel single crystal in the absence and presence of a saturated magnetic field. Small-scale parameters such as Young's modulus, indentation hardness, and plastic index are dependent on the applied magnetic field, which differ greatly from their macroscale counterparts. Possible mechanisms that induced 31% increase in modulus and 7% reduction in hardness (i.e., the flexomagnetic effect and the interaction between dislocations and magnetic field, respectively) are analyzed and discussed. Results could be useful in the microminiaturization of applications, such as tunable mechanical resonators and magnetic field sensors. PMID:24695002

  7. ENTREPRENEURIAL LEADERSHIP AND ORGANIZATIONAL PERFORMANCE WITH REFERENCE TO RURAL SMALL SCALE ENGINEERING INDUSTRY IN PUNE DISTRICT

    Directory of Open Access Journals (Sweden)

    Dilip Jagdale

    2014-08-01

    Full Text Available Entrepreneurial Leadership is a significant concept in entrepreneurship literature. Different leadership styles effect on effectiveness and performance of the organizations. Present research investigates the impact ofEntrepreneurial Leadership style onOrganizational Performance with reference to Rural Small Scale Engineering Industry in Pune District of India. A ten items scale developed by (Boltan 2012 was used to find leadership styles. The data werecollected from one hundred and forty four (144 entrepreneursfrom Rural Small Scale Engineering Industryof 13 tehsils of in Pune District of India. For statistical analysis Mean, Standard Deviation, T-Test, and Chi-square test were used. Study concludes that there is no significant association between leadership styles and organizational performance.

  8. Transient downflows associated with the intensification of small-scale magnetic features and bright point formation

    CERN Document Server

    Narayan, G

    2011-01-01

    Small-scale magnetic features are present everywhere in the solar photosphere. Theoretical models, numerical calculations, and simulations describing the formation of these features have existed for a few decades, but there are only a few observational studies in direct support of the simulations. In this study we present the evolution of small-scale magnetic features with a spatial resolution close to 0.15 arcsecond and compare these observations with those predicted by numerical simulations and also with previous observational work of a similar nature. We analyze a 40 min time sequence of full Stokes spectropolarimetric 630.25 nm data from a plage region near the Sun center. We use line-of-sight velocities and magnetic field measurements obtained using Milne-Eddington inversion techniques with and without stray-light compensation along with measured continuum and line minimum intensities. We discuss the results in relation to earlier observations and simulations. We present eight cases involving strong down...

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

    International Nuclear Information System (INIS)

    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

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

    Scientific Electronic Library Online (English)

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

    1651-16-01

    Full Text Available 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, ar [...] e 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 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

  11. Alternatives to R_lambda-scaling of Small-Scale Turbulence Statistics

    CERN Document Server

    Hill, R J

    2001-01-01

    Traditionally, trends of universal turbulence statistics are presented versus R-lambda, which is the Reynolds number based on Taylor's scale, lambda, and the root-mean-squared (rms) velocity, u'. Taylor's scale and u', and hence R-lambda, do not have the attribute of universality. The ratio of rms fluid-particle acceleration to rms viscous acceleration and the ratio of rms pressure-gradient acceleration to rms viscous accleration are alternatives to R-lambda which have the advantage of being determined by the small scales of turbulence. These ratios have the following attributes: they have the meaning of Reynolds number, are dimensionless, are composed of statistics of the small scales of turbulence: can be evaluated with single-wire hot-wire anemometry, and like R-lambda, can be partially evaluated by means of flow similarity.

  12. Financing Energy Services for Small-scale Energy-users - project FINESSE

    International Nuclear Information System (INIS)

    This paper presents the FINESSE (Financing Energy Services for Small-scale Energy users) launched in 1989 by World Bank 's Energy Sector Assistance Program (ESMAP) in association with the US Department of Energy and the Netherlands Ministry for Development Cooperation, whose purpose is to address financial, institutional and policy issues related to enhancing energy services for residential and commercial energy consumers in the Developing World. It describes the related technology benefits of renewable energy and energy efficiency, as well as a technology overview and outlines the strategies for financing alternatives in the Developing World. It concludes with a description of successful experiences in small-scale energy services, especially in Asia. (TEC). 8 figs

  13. RADAR upper hybrid resonance scattering diagnostics of small-scale fluctuations and waves in tokamak plasmas

    International Nuclear Information System (INIS)

    The upper hybrid resonance (UHR) scattering technique possessing such merits as one-dimensional probing geometry, enhancement of cross section, and fine localization of scattering region is modified in the new diagnostics under development to achieve wave number resolution. The fluctuation wave number is estimated in the new technique from the scattering signal time delay measurements. The feasibility of the scheme is checked in the proof of principal experiment in a tokamak. The time delay of the UHR scattering signal exceeding 10 ns is observed. The small scale low frequency density fluctuations are investigated in the UHR RADAR backscattering experiment. The UHR cross-polarization scattering signal related to small scale magnetic fluctuations is observed. The lower hybrid (LH) wave propagation and both linear and nonlinear wave conversion are investigated. The small wavelength (??0.02 cm) high number ion Bernstein harmonics, resulting from the linear wave conversion of the LH wave are observed in a tokamak plasma for the first time

  14. Watermill and Small-Scale Hydroelectric Power Plant Landscapes Assessed According to Ecological Aspects

    Directory of Open Access Journals (Sweden)

    Lilita Lazd?ne

    2013-10-01

    Full Text Available Research of watermill and small-scale hydroelectric power plant (HPP landscapes in Latvia according to ecological aspects is a part of a more complex research. The aim of this research is to examine the existing situation of watermill and small-scale HPP landscapes in Latvia by applying the ecological assessment criteria, and then try to formulate a definition of common tendencies of the landscape character. This paper provides a landscape inventory matrix for research in the field stu­dies of landscape identification at the local planning level. The duration of the research was from 2010 to 2012. The research includes 42 territories starting with the three most densely developed areas in Latvia: in Latgale, Kurzeme and Vidzeme uplands distribution ranges. The research results reflect tendencies of the landscape features assessed according to the previously developed criteria of ecological aspects.

  15. Diffraction of electromagnetic waves by small scale geomagnetic field-aligned density striations

    International Nuclear Information System (INIS)

    A powerful electromagnetic wave in the ordinary mode transmitted near vertically into the ionospheric F region excites small scale density filaments which are stretched along the geomagnetic field. These striations are associated with a number of electromagnetically driven plasma phenomena, such as anomalous absorption of electromagnetic waves, anomalous heating, and stimulation of electromagnetic emissions. The diffraction of an electromagnetic wave is studied theoretically in a cold plasma as it propagates at small angles to striations which have a small scale across the ambient magnetic field. For a sufficiently high number density of striations the stationary self-consistent wave electric field distribution consists of several independent beams. As a result the pump-induced striations are grouped in independent patches in the plane across the magnetic field. Such bunches of striations may have been detected in in situ measurements from a sounding rocket at Arecibo and as large scale density irregularities observed at Tromsoe

  16. Legal obstacles and incentives to the development of small scale hydroelectric power in Kentucky

    Energy Technology Data Exchange (ETDEWEB)

    None,

    1980-05-01

    The legal and institutional obstacles to the development of small-scale hydroelectric energy at the state level are examined. The introductory section examines the dual regulatory system from the standpoint of the appropriate legal doctrine, the law of pre-emption, application of the law to the case of hydroelectric development, and concludes with an inquiry into the practical use of the doctrine by the FERC. Additional sections cover acquisition; liability; Department for Natural Resources and Environmental Protection; energy utilities; local regulations; incidental impacts; financial considerations; and sources of information. In Kentucky, many of the impacts have not been implemented with regard to small-scale hydroelectric energy, since in Kentucky most electricity is coal-generated and any hydroelectric power that does exist, is derived from TVA or the Army Corp of Engineer projects.

  17. Probing small-scale non-Gaussianity from anisotropies in acoustic reheating

    CERN Document Server

    Naruko, Atsushi; Yamaguchi, Masahide

    2015-01-01

    We give new constraints on small-scale non-Gaussianity of primordial curvature perturbations by the use of anisotropies in acoustic reheating. Mixing of local thermal or local kinetic equilibrium systems with different temperatures yields a locally averaged temperature rise, which is proportional to the square of temperature perturbations damping in the photon diffusion scale. Such secondary temperature perturbations are indistinguishable from the standard temperature perturbations linearly coming from primordial curvature perturbations and hence should be subdominant compared to the standard ones. We show that small-scale higher order correlation functions (connected non-Gaussian and disconnected Gaussian parts) of primordial curvature perturbations can be probed by investigating auto power spectrum of the generated secondary perturbations and the cross power spectrum with the standard perturbations. This is simply because these power spectra come from higher order correlation functions of primordial curvatu...

  18. Destruction of small-scale dark matter clumps in the hierarchical structures and galaxies

    International Nuclear Information System (INIS)

    A mass function of small-scale dark matter clumps is calculated in the standard cosmological scenario with an inflationary-produced primordial fluctuation spectrum and with a hierarchical clustering. We take into account the tidal destruction of clumps at early stages of structure formation starting from a time of clump detachment from the Universe expansion. Only a small fraction of these clumps, ?0.1%-0.5%, in each logarithmic mass interval ?logM?1 survives the stage of hierarchical clustering. The surviving clumps can be disrupted further in the galaxies by tidal interactions with stars. We performed the detailed calculations of the tidal destruction of clumps by stars in the Galactic bulge and halo and by the Galactic disk itself. It is shown that the Galactic disc provides the dominant contribution to the tidal destruction of small-scale clumps outside the bulge. The results obtained are crucial for calculations of the dark matter annihilation signal in the Galaxy

  19. Mesogranulation and small-scale dynamo action in the quiet Sun

    CERN Document Server

    Bushby, Paul J

    2014-01-01

    Regions of quiet Sun generally exhibit a complex distribution of small-scale magnetic field structures, which interact with the near-surface turbulent convective motions. Furthermore, it is probable that some of these magnetic fields are generated locally by a convective dynamo mechanism. In addition to the well-known granular and supergranular convective scales, various observations have indicated that there is an intermediate scale of convection, known as mesogranulation, with vertical magnetic flux concentrations accumulating preferentially at mesogranular boundaries. Our aim is to investigate the small-scale dynamo properties of a convective flow that exhibits both granulation and mesogranulation, comparing our findings with solar observations. Adopting an idealised model for a localised region of quiet Sun, we use numerical simulations of compressible magnetohydrodynamics, in a 3D Cartesian domain, to investigate the parametric dependence of this system (focusing particularly upon the effects of varying ...

  20. Potential market for small-scale gasifiers in rural areas of developing countries

    OpenAIRE

    Kieffer, Benoit

    2014-01-01

    This thesis report assesses the potential market for small-scale gasifiers in rural areas of developing countries and regions. Biomass is already widely used in these areas for energetic purpose, giving gasification an interesting niche market for remote electricity production. Success factors include a high reliability, an efficient biomass supply chain and sufficient local electricity needs. Suitable fuel for a gasifier must be available at low cost, which could be wood harvested locally or...

  1. Small-scale medical waste incinerators : experiences and trials in South Africa

    OpenAIRE

    Rogers, David E.C.; Brent, Alan Colin

    2006-01-01

    Formal waste management services are not accessible for the majority of primary healthcare clinics on the African continent, and affordable and practicable technology solutions are required in the developing country context. In response, a protocol was established for the first quantitative and qualitative evaluation of relatively low cost small-scale incinerators for use at rural primary healthcare clinics. The protocol comprised the first phase of four, which defined the comprehensive trial...

  2. Optimization Study of Small-Scale Solar Membrane Distillation Desalination Systems (s-SMDDS)

    OpenAIRE

    Hsuan Chang; Cheng-Liang Chang; Chen-Yu Hung; Tung-Wen Cheng; Chii-Dong Ho

    2014-01-01

    Membrane distillation (MD), which can utilize low-grade thermal energy, has been extensively studied for desalination. By incorporating solar thermal energy, the solar membrane distillation desalination system (SMDDS) is a potential technology for resolving energy and water resource problems. Small-scale SMDDS (s-SMDDS) is an attractive and viable option for the production of fresh water for small communities in remote arid areas. The minimum cost design and operation of s-SMDDS are determin...

  3. Certifying improvement, improving certification: An analysis based on the artisanal and small-scale mining sector

    OpenAIRE

    Bodenheimer, Miriam

    2013-01-01

    There are a plethora of voluntary initiatives indirectly connected to artisanal and small-scale mining (ASM), but until recently, none of these standards were explicitly concerned with ASM. It is only with the introduction of certification schemes specific to the ASM sector that guidelines are being designed and implemented that expressly address its unique dynamics. But implementing certification schemes remains costly and it is therefore important to analyze in detail to what degree problem...

  4. The Rural Landscapes and Small-Scale Agricultural Practices in the Transylvanian Plain

    OpenAIRE

    Baciu, Nicolae; Malos?, Cristian; Ros?ian, Gheorghe; Mures?ianu, Mircea; Schuster, Eduard; Barta, Andras; Sta?nescu, Carmen; Muntean, Octavian-liviu; Miha?iescu, Radu

    2010-01-01

    This paper is focused on the relationships between small-scale agricultural practices and cultural landscape of Transylvanian Plain. The geographical position of Transylvanian Plain in central part of Romania shows with relevance its favourability for sustainable agriculture and developing assumptions. Despite of this, the region was kept outside of the major infrastructural and economic trends. We could, also, include the Transylvanian Plain into a typical rural “central isolation space”...

  5. Fabrication and testing of small scale mock-ups of ITER shielding blanket

    International Nuclear Information System (INIS)

    Small scale mock-ups of the primary first wall, the baffle first wall, the shield block and a partial model for the edge of the primary first wall module were designed and fabricated incorporating most of the key design features of the ITER shielding blanket. All mock-ups featured the DSCu heat sink, the built-in SS coolant tubes within the heat sink and the SS shield block. CFC tiles was used as the protection armor for the baffle first wall mock-up. The small scale shield block mock-up, integrated with the first wall, was designed to have a poloidal curvature specified in the ITER design. Fabrication routes of mock-ups were decided based on the single step solid HIP of DSCu/DSCu, DSCu/SS and SS/SS reflecting the results of previous joining techniques development and testing. For attaching the CFC tiles onto DSCu heat sink in the fabrication of the baffle first wall mock-up, a two-step brazing was tried. All mock-ups and the partial model were successfully fabricated with a satisfactory dimensional accuracy. The small scale primary first wall mock-up was thermo-mechanically tested under high heat fluxes of 5-7 MW/m2 for 2500 cycles in total. Satisfactory heat removal performance and integrity of the mock-up against cyclic high heat flux loads were confirmed by measurement during the tests and destructive examination after the tests. Similar high heat flux tests were also performed with the small scale baffle first wall mock-up under 5-10 MW/m2 for 4500 cycles in total resulting in sufficient heat removal capability and integrity confirmed by measurements during the tests. (author)

  6. Fractographic study of high-density polyethylene gas pipe following Small Scale Steady State test

    OpenAIRE

    Pusz, A.; Michalik, K.

    2010-01-01

    Purpose: The present work attempts to examine the failure performance of high density polyethylene [HDPE] gas pipe through a fractographic study of the fracture morphology following Small Scale Steady State test (S4). Failure mechanisms are discussed based on the fracture morphologies resulting from these tests. There are many instances where the rapid propagation of cracks is the result of fluid pressure acting on piping structures. This problem is recognized as one of the most important iss...

  7. Feasibility of small-scale gas engine-based residential cogeneration in Spain

    International Nuclear Information System (INIS)

    Nowadays all countries are developing their own policies to promote cogeneration in the small-scale residential sector. In this paper the feasibility of small-scale gas engine-based residential cogeneration plants under the current Spanish regulation is studied. A unitary thermal load profile is obtained to characterised the thermal demand of residential applications in Spain. This unitary profile is used to analyse the potential of cogeneration in the small-scale range of powers (100-1000 kW). A complete characterisation of the gas fuelled engines in the market is performed and subsequently used to evaluate the economic feasibility within the selected range by means of a self-tailored simulation model. It is underlined how the thermal storage is a crucial element that should be suitably included in a residential cogeneration plant and the distortions that the actual pricing system adds to the profitability of residential plants of different sizes. Finally a sensibility study is carried out in order to evaluate how the Spanish regulation is able to deal with future variations in the energy prices. It is shown that a rise in the price of the natural gas increases the current feasibility of a plant while a decrease descends the profitability. - Highlights: ? Profitability is obtained within the whole small-scale range of powers. ? The stepped structure of prices strongly affect the feasibility of the projects. ? The inclusion of thermal storage notably affects the thermal storage notably affects the profitability of the plant. ? Big chance for increase the feasibility exists in retrofitting old installations. ? The system of tariff updating balances the future variations in the price of fuels.

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

    CERN Document Server

    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

    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.

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

    OpenAIRE

    Peterson, J. B.; Griffin, G. S.; Newcomb, M. G.; Alvarez, D. L.; Cantalupo, C. M.; Morgan, D.; Miller, K. W.; Ganga, K.; Pernic, D.; Thoma, M.

    1999-01-01

    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.

  10. Design of a small-scale organic Rankine cycle engine used in a solar power plant

    OpenAIRE

    Georges, Emeline; Declaye, Sébastien; Dumont, Olivier; Quoilin, Sylvain; Lemort, Vincent

    2013-01-01

    Under the economic and political pressure due to the depletion of fossil fuels and global warming concerns, it is necessary to develop more sustainable techniques to provide electrical power. In this context, the present study aims at designing, building and testing a small-scale organic Rankine cycle (ORC) solar power plant ( 3 kWe) in order to define and optimize control strategies that could be applied to larger systems. This paper presents a first step of the design of the s...

  11. Small scale purification of human pituitary lutropin (hLH) for use in radioligand assays

    International Nuclear Information System (INIS)

    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 radioassays. Starting from 10 and 20 hypophyses after Sephadex G 100 purification, 10 ?g/gland with approximate 10% purity was obtained. After the last purification, hLH recovery was of 1.5 ?g/gland. (author)

  12. Mobile Phone usage by Micro and Small Scale Enterprises in Semi-Rural Ghana

    OpenAIRE

    Paul Adjei kwakwa

    2012-01-01

    This work looked at the use of mobile technology among entrepreneurs/managers of micro and small scale businesses in the Akuapem North district of Ghana. The major findings were that entrepreneurs/business managers would use more than one mobile phone and/or subscribed to more than one network in order to make affordable calls, to enjoy excellent service from other network providers, for business purposes, security reasons and to have a place for their many contact numbers. Apart from marketi...

  13. Constraints on small-scale cosmological fluctuations from SNe lensing dispersion

    OpenAIRE

    Ben-dayan, Ido; Takahashi, Ryuichi

    2015-01-01

    We provide predictions on small-scale cosmological density power spectrum from supernova lensing dispersion. Parameterizing the primordial power spectrum with running $\\alpha$ and running of running $\\beta$ of the spectral index, we exclude large positive $\\alpha$ and $\\beta$ parameters which induce too large lensing dispersions over current observational upper bound. We ran cosmological N-body simulations of collisionless dark matter particles to investigate non-linear evol...

  14. Linkages, access to finance and the performance of small-scale enterprises in Kenya

    OpenAIRE

    Atieno, Rosemary

    2009-01-01

    Micro- and small-scale enterprises (MSEs) have become important players in the Kenyan economy, but at the same time they continue to face constraints that limit their development. Lack of access to financial services is one of the main constraints, and a number of factors have been identified to explain this problem. These include the segmented and incomplete nature of financial markets, which increases transaction costs associated with financial services. On the supply side, most formal fina...

  15. Development of a simulation model for a small scale renewable energy system / Martinus Gerhardus de Klerk

    OpenAIRE

    De Klerk, Martinus Gerhardus

    2012-01-01

    In this dissertation I present my approach and findings regarding the development of a simulation model for a small scale renewable energy system. A brief introduction provides the reader with the background as to why there is a need for such a simulation package. The project objectives, research methodology and the research contributions originating from the project is also described. A literature study was done on all the relevant technologies constituting the renewable en...

  16. Climate change, poverty and food security :the role of the small-scale fisheries sector

    OpenAIRE

    Singh, Balbir; Steinshamn, Stein Ivar

    2005-01-01

    Coastal small scale fisheries and communities in the developing countries are vulnerable to global climate change. The consequences occur directly due to the impact of rising temperatures on movement of fish resources and indirectly as climate change impacts on other sectors of the economy thereby imposing increased pressure on already overexploited coastal fisheries. A stylistic two-sector dynamic bio-economic model is specified for modelling intra- and inter-sectoral impacts of climate chan...

  17. Feasibility Study of Small Scale Standalone Wind Turbine for Urban Area : Case study: KTH Main Campus

    OpenAIRE

    Gebrelibanos, Kalekirstos Gebremariam

    2013-01-01

    The recent worldwide economic crisis, climate change and global warming have emphasized that the need for low carbon emissions while also ensuring the economic feasibility. In this paper, wind power potential of ETD in KTH was investigated. The technical and economical feasibility of tower mounted small scale standalone wind turbine installation is conducted. The potential of wind power production was statistically analysed. The average wind speed data of four-season interval of one year peri...

  18. A statistical approach to represent small-scale variability of permafrost temperatures due to snow cover

    OpenAIRE

    Gisna?s, K.; Westermann, S.; Schuler, T. V.; Litherland, T.; Isaksen, K.; Boike, J.; Etzelmu?ller, B.

    2014-01-01

    In permafrost environments exposed to strong winds, drifting snow can create a small-scale pattern of strongly variable snow heights which has profound implications for the thermal regime of the ground. Arrays of 26 to more than 100 temperature loggers were installed to record the distribution of ground surface temperatures within three study areas across a climatic gradient from continuous to sporadic permafrost in Norway. A variability of the mean annual ground surface temper...

  19. ENTREPRENEURIAL LEADERSHIP: EMPLOYEE PERCEPTION AND ORGANIZATIONAL PERFORMANCE IN RURAL SMALL SCALE ENGINEERING INDUSTRY

    Directory of Open Access Journals (Sweden)

    Dilip Dnyandeo Jagdale

    2015-01-01

    Full Text Available Entrepreneurial Leadership is a relatively new, sometimes controversial, andburgeoning field of management research. Significance of this concept is increasing day by day in entrepreneurship literature. Entrepreneur’s different leadership styles effect on performanceof the organizations. Present research investigates the impact of employee perceived EntrepreneurialLeadership style on Organizational Performance. Study is conducted with reference to RuralSmall Scale Engineering Industry in Pune District of India.

  20. Social Learning as a Basis for Cooperative Small-Scale Forest Management

    OpenAIRE

    Dedeurwaerdere, Tom

    2009-01-01

    This paper analyses the governance characteristics of an innovative policy instrument for sustainable forest management in Flanders, namely a mechanism based on social learning and collaborative planning within joint forest management organizations. These organizations have been successful in involving non-industrial private forest owners in managing the transition towards sustainable management in small-scale forestry. Why was this innovative scheme successful? And what are its shortcomings ...

  1. Small-scale Gradients of Charged Particles in the Heliospheric Magnetic Field

    OpenAIRE

    Guo, Fan; Giacalone, Joe

    2013-01-01

    Using numerical simulations of charged-particles propagating in the heliospheric magnetic field, we study small-scale gradients, or "dropouts", in the intensity of solar energetic particles seen at 1 AU. We use two turbulence models, the foot-point random motion model (Jokipii & Parker 1969; Giacalone et al. 2006) and two-component model (Matthaeus et al. 1990), to generate fluctuating magnetic fields similar to spacecraft observations at 1 AU. The turbulence models include ...

  2. An Algebraic Approach for the MIMO Control of Small Scale Helicopter

    OpenAIRE

    Budiyono, A.; Sudiyanto, T.

    2008-01-01

    The control of small-scale helicopter is a MIMO problem. To use of classical control approach to formally solve a MIMO problem, one needs to come up with multidimensional Root Locus diagram to tune the control parameters. The problem with the required dimension of the RL diagram for MIMO design has forced the design procedure of classical approach to be conducted in cascaded multi-loop SISO system starting from the innermost loop outward. To implement this control approach f...

  3. Need assessment of electricity in Namibia : Prerequisites for implementation of a small scale wind turbine

    OpenAIRE

    Koskela, Martin; Uman, Emil

    2015-01-01

    Namibia is one of the most sparsely populated countries with a total area of 825 600 km2. There are still many residents in the country without access to electricity, and with the present rapid technological development the need for electricity is increasing constantly. However, the expansion of the electricity grid is slow and costly, resulting in that many cannot afford to be connected and therefore a clear need for small scale electricity production has been identified. For this reason it ...

  4. 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

  5. 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

  6. An assessment of stability and growth pact reform proposals in a small-scale macro framework

    OpenAIRE

    Creel, Je?ro?me; Hubert, Paul; Saraceno, Francesco

    2012-01-01

    This paper contributes to the debate on fiscal governance for the European Monetary Union, assessing the different fiscal rules currently discussed. We simulate a small scale macroeconomic model with forward looking agents, augmented with a public finances block. We account for both the positive (output stabilization) and negative (via risk premia) effects of debt and deficit. By the appropriate choice of the exogenous fiscal variables, in the fiscal block, we replicate the working of the rul...

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

    Directory of Open Access Journals (Sweden)

    Igor Ani?

    2011-04-01

    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.

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

    OpenAIRE

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

    2013-01-01

    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. ...

  9. The Atacama Cosmology Telescope: likelihood for small-scale CMB data

    OpenAIRE

    Dunkley, J; CALABRESE, E; Sievers, J; Addison, GE; Battaglia, N.; Battistelli, ES; Bond, JR; S. DAS; Devlin, MJ; Duenner, R; Fowler, JW; Gralla, M.; A. Hajian; Halpern, M; Hasselfield, M.

    2013-01-01

    The Atacama Cosmology Telescope has measured the angular power spectra of microwave fluctuations to arcminute scales at frequencies of 148 and 218 GHz, from three seasons of data. At small scales the fluctuations in the primordial Cosmic Microwave Background (CMB) become increasingly obscured by extragalactic foregounds and secondary CMB signals. We present results from a nine-parameter model describing these secondary effects, including the thermal and kinematic Sunyaev-Zel'dovich (tSZ and k...

  10. Small-scale response of plant species to land-use intensification

    OpenAIRE

    Fédoroff, Eric; Ponge, Jean-François; Dubs, Florence,; Fernández-González, Federico; Lavelle, Patrick

    2005-01-01

    Plant communities are affected by land-use and landscape heterogeneity and can be used as indicators of environmental change. At small-scale, species composition and species richness of plant communities are influenced by local environment and by diaspores from the surroundings. Thus, they reflect the influence of both land-use type and land-use diversity. Plant community composition was studied along a gradient of agricultural disturbance in the Morvan Regional Natural Park (Burgundy, France...

  11. MOTIVATIONAL FACTORS AND STATUS OF WOMEN ENTREPRENEUR'S IN SMALL SCALE INDUSTRIES: A CRITICAL REVIEW

    OpenAIRE

    Radhika M. K; B. Siddappa

    2014-01-01

    Women entrepreneurship in small scale industries play very important role in economy. Entrepreneurship amongst women has been a recent concern. Women have become aware of their existence their rights and their work situation. However, women are not too eager to alter their role in fear of social backlash. The progress is more visible among men families in society. This paper focuses on women entrepreneur. Any understanding of Indian women, of their identity, and especially...

  12. The Challenges Facing Small-Scale Women Entrepreneurs: A Case of Kenya

    OpenAIRE

    Fridah Muriungi Mwobobia

    2012-01-01

    The study sought to identify the challenges facing small scale women entrepreneurs in Kenya and initiatives put in place to counter the challenges. The study employed desktop research. MSEs Baseline survey, recorded that 612,848 women in Micro and Small Enterprises (MSEs) in Kenya, accounting for 47.4 per cent of all those in MSEs. The study showed that women tended to operate enterprises associated with traditional women’s roles, such as hairstyling. The small and micro enterprises (SMEs) ...

  13. The Large scale instability in rotating fluid with small scale force

    CERN Document Server

    Kopp, M I; Yanovsky, V V

    2015-01-01

    In this paper, we find a new large scale instability displayed by a rotating flow in forced turbulence. The turbulence is generated by a small scale external force at low Reynolds number. The theory is built on the rigorous asymptotic method of multi-scale development. The nonlinear equations for the instability are obtained at the third order of the perturbation theory. In this article, we explain a detailed study of the nonlinear stage of the instability and generation vortex kinks.

  14. A New Object-Weighted Measure of the Small-Scale Velocity Dispersion

    OpenAIRE

    Baker, Jonathan E.; Davis, Marc

    1999-01-01

    We describe a new statistic for measuring the small-scale velocity dispersion of galaxies directly from redshift surveys. This statistic is based on the object-weighted statistic proposed by Davis, Miller, & White (1997). Compared with the traditional pair-weighted velocity dispersion, our statistic is less sensitive to the presence or absence of rare, rich clusters of galaxies. This measure of the thermal energy of the galaxy distribution is ideally suited for use with a fi...

  15. DEVELOPMENT OF SMALL INJECTION MOULDING MACHINE FOR FORMING SMALL PLASTIC ARTICLES FOR SMALL-SCALE INDUSTRIES

    OpenAIRE

    OYETUNJI, A.

    2010-01-01

    Development of small injection moulding machine for forming small plastic articles in small-scale industries was studied. This work which entailed design, construction and test small injection moulding machine that was capable of forming small plastic articles by injecting molten resins into a closed, cooled mould, where it solidifies to give the desired products was developed. The machine was designed and constructed to work as a prototype for producing very small plastic components. Design ...

  16. The challenging modelling of kLa in a periodic constricted small-scale tube

    OpenAIRE

    Reis, N.; Vicente, A. A.; Teixeira, J. A.

    2005-01-01

    An extensive use in chemistry, biological and pharmaceutical laboratories is envisaged for a novel continuous screening reactor based on the oscillatory flow technology (Harvey, 2001). The basic unit of this reactor was recently presented by Harvey et al. (2003) and Reis et al. (2004) and consists in a 4.4 mm internal diameter and 350 mm long jacketed glass small-scale tube provided with smooth periodic constrictions, SPCs (Figure 1). Prediction of fluid mixing and residence time within th...

  17. Small-scale primordial magnetic fields and anisotropies in the cosmic microwave background radiation

    Energy Technology Data Exchange (ETDEWEB)

    Jedamzik, Karsten [Laboratoire de Univers et Particules, UMR5299-CNRS, Université de Montpellier II, F-34095 Montpellier (France); Abel, Tom, E-mail: karsten.jedamzik@um2.fr, E-mail: tabel@slac.stanford.edu [Kavli Institute for Particle Astrophysics and Cosmology, SLAC/Stanford University, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States)

    2013-10-01

    It is shown that small-scale magnetic fields present before recombination induce baryonic density inhomogeneities of appreciable magnitude. The presence of such inhomogeneities changes the ionization history of the Universe, which in turn decreases the angular scale of the Doppler peaks and increases Silk damping by photon diffusion. This unique signature could be used to (dis)prove the existence of primordial magnetic fields of strength as small as B ? 10{sup ?11} Gauss by cosmic microwave background observations.

  18. Small-scale primordial magnetic fields and anisotropies in the cosmic microwave background radiation

    International Nuclear Information System (INIS)

    It is shown that small-scale magnetic fields present before recombination induce baryonic density inhomogeneities of appreciable magnitude. The presence of such inhomogeneities changes the ionization history of the Universe, which in turn decreases the angular scale of the Doppler peaks and increases Silk damping by photon diffusion. This unique signature could be used to (dis)prove the existence of primordial magnetic fields of strength as small as B ? 10?11 Gauss by cosmic microwave background observations

  19. On the ultraviolet signatures of small scale heating in coronal loops

    OpenAIRE

    Parenti, Susanna; Young, Peter R

    2010-01-01

    Studying the statistical properties of solar ultraviolet emission lines could provide information about the nature of small scale coronal heating. We expand on previous work to investigate these properties. We study whether the predicted statistical distribution of ion emission line intensities produced by a specified heating function is affected by the isoelectronic sequence to which the ion belongs, as well as the characteristic temperature at which it was formed. Particul...

  20. Fractal Properties and Small-scale Structure of Cosmic String Networks

    OpenAIRE

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

    2005-01-01

    We present results from a detailed numerical study of the small-scale and loop production properties of cosmic string networks, based on the largest and highest resolution string simulations to date. We investigate the non-trivial fractal properties of cosmic strings, in particular, the fractal dimension and renormalised string mass per unit length, and we also study velocity correlations. We demonstrate important differences between string networks in flat (Minkowski) space...

  1. A small scale accelerator driven subcritical assembly development and demonstration experiment at LAMPF

    International Nuclear Information System (INIS)

    A small scale experiment designed to demonstrate many of the aspects of accelerator-driven transmutation technology is described. The experiment uses the high-power proton beam from the Los Alamos Meson Physics Facility accelerator to produce neutrons with a molten Lead target. The target is surrounded by a molten salt and graphite moderator blanket. Fissionable material can be added to the molten salt to demonstrate Plutonium burning or transmutation of commercial spent fuel or energy production from Thorium

  2. Selection of Technical Reactor Equipment for Modular, Continuous Small-Scale Plants

    OpenAIRE

    Nicolai Krasberg; Lukas Hohmann; Thomas Bieringer; Christian Bramsiepe; Norbert Kockmann

    2014-01-01

    Fast process development, flexible production and the utilization of advanced process conditions are the main goals of modular and continuous small-scale plants (MCSPs). A configurable layout of the modules and the use of predefined equipment enable a quick and reliable conceptual process development and scale-up of continuous processes. Therefore, a computer-assisted selection methodology was developed and is presented, which allows the quick selection of plug flow reactor equipment for homo...

  3. Measurements of Small-Scale-Density Inhomogeneities in a Laser Plasma Using Near Forward Scattering

    Science.gov (United States)

    Moody, J. D.; MacGowan, B. J.; Kirkwood, R. K.; Glenzer, S. H.; Kruer, W. L.; Williams, E. A.; Afeyan, B. B.; Schmitt, A. J.

    1998-11-01

    Forward scattered light from a 351-nm probe laser is used to infer the nature of small-scale ( <= 0.05 with a transverse spatial correlation length of several laser wavelengths. Various laser smoothing techniques (SSD and polarization smoothing) tend to decrease the forward scattered light and the associated fluctuation level. We will discuss the correlation between the forward and backscattered light and describe the dependence of the fluctuations on the plasma characteristics.

  4. Small-scale structure formation properties of chilled sterile neutrinos as dark matter

    OpenAIRE

    Petraki, Kalliopi

    2008-01-01

    We calculate the free-streaming length and the phase space density of dark-matter sterile neutrinos produced from decays, at the electroweak scale, of a gauge singlet in the Higgs sector. These quantities, which depend on the dark-matter production mechanism, are relevant to the study of small-scale structure formation and may be used to constrain or rule out dark-matter candidates.

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

    Energy Technology Data Exchange (ETDEWEB)

    James O' Brien

    2012-09-01

    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.

  6. Informal Credit Markets and the Development of Micro and Small Scale Enterprises in Nigeria

    OpenAIRE

    Ojenike Joseph Ojenike; Akinleye Gideon Tayo

    2012-01-01

    This study analyzed the development in investment of Micro and Small Scale Enterprises Intermediated by theinformal credit market in Nigeria. Primary data for this study were collected from 10 (ten) Local GovernmentAreas 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 smallscale enterprises. Policy aimed at making fund increasingly av...

  7. ENTREPRENEURIAL LEADERSHIP AND ORGANIZATIONAL PERFORMANCE WITH REFERENCE TO RURAL SMALL SCALE ENGINEERING INDUSTRY IN PUNE DISTRICT

    OpenAIRE

    Dilip Jagdale; Sarang Shankar Bhola

    2014-01-01

    Entrepreneurial Leadership is a significant concept in entrepreneurship literature. Different leadership styles effect on effectiveness and performance of the organizations. Present research investigates the impact ofEntrepreneurial Leadership style onOrganizational Performance with reference to Rural Small Scale Engineering Industry in Pune District of India. A ten items scale developed by (Boltan 2012) was used to find leadership styles. The data werecollected from one h...

  8. Low Discounting Behavior among Small-Scale Fishers in Fiji and Sabah, Malaysia

    OpenAIRE

    Louise S. L. Teh; Lydia C. L. Teh; U. Rashid Sumaila

    2011-01-01

    Understanding the socio-economic factors that are associated with fishers’ willingness to delay gratification may be useful for designing appropriate fisheries management and conservation policies. We aim to identify the predictors of low discounting behaviour among fishers, which is analogous to having a longer-term outlook. We base our empirical study on two small-scale tropical reef fisheries in Sabah, Malaysia, and Fiji. We use an experimental approach to identify fishers with low discoun...

  9. Field investigation of preferential fissure flow paths with hydrochemical analysis of small-scale sprinkling experiments

    OpenAIRE

    Krzeminska, D.M.; Bogaard, T. A.; T.-H. Debieche; Cervi, F.; V. Marc; J.-P. Malet

    2014-01-01

    The unsaturated zone largely controls groundwater recharge by buffering precipitation while at the same time providing preferential flow paths for infiltration. The importance of preferential flow on landslide hydrology is recognised in the literature; however, its monitoring and quantification remain difficult. This paper presents a combined hydrological and hydrochemical analysis of small-scale sprinkling experiments. It aims at showing the potential of such experim...

  10. Large- and small-scale turbulent spectra in MHD and atmospheric flows

    Directory of Open Access Journals (Sweden)

    O. G. Chkhetiani

    2006-01-01

    Full Text Available In the present review we discuss certain studies of large- and small-scale turbulent spectra in MHD and atmospheric flows performed by S. S. Moiseev and his co-authors during the last years of his life and continued by his co-authors after he passed away. It is shown that many ideas developed in these works have not lost their novelty and urgency until now, and can form the basis of future studies in this field.

  11. Environmental changes, agricultural crisis and small-scale fishing development in the Casamance region, Senegal

    OpenAIRE

    Cormier Salem, Marie-Christine

    1994-01-01

    Senegal is a West African country where the fishing industry is one of the most important sources of economic development. However, Senegal is currently experiencing a deep political and economic crisis, partly linked to the Sahel drought. In this context, international interventions have been necessary to sustain economy, in particular to ensure the survival of small-scale fisheries. The last 15 years have seen an increasing number of development projects in Casamance, the Southern region of...

  12. The Role of Accounting Information in the Survival of Small Scale Businesses in Warri, Delta State, Nigeria

    Directory of Open Access Journals (Sweden)

    Okoh, L. O.

    2012-04-01

    Full Text Available Small scale enterprises play a vital role in the economic development of any country. In Nigeria, the management of these enterprises have been constrained by lack of knowledge of accounting by the stakeholders. This study aimed at examining the roles of accounting information in the survival of small businesses in Warri, Delta State, Nigeria. The study spotlighted the importance of small scale enterprises in the development of Nigerian economy, problems that pose a threat to the survival of small scale businesses and the relevance of accounting information to the operations of a business/organization. Structured questionnaire was employed in the course of gathering relevant data for the study. 100 employees from twenty small scale enterprises in Warri, Delta State were randomly selected for the study. While chi-square statistical technique was used in data analysis. The results indicated among others that the success of small scale business enterprises in Nigeria depends greatly but not solely in accounting information; that most small scale businesses do not keep accounting records due to ignorance about accounting information. The study therefore concluded that for small scale businesses to function successfully, adequate accounting information is necessary therefore managers of small businesses should employ and utilize the services of professional accountants who perform expert and useful accounting services to small scale firms in order to improve on their operational performance.

  13. Mixing at mid-ocean ridges controlled by small-scale convection and plate motion

    Science.gov (United States)

    Samuel, Henri; King, Scott D.

    2014-08-01

    Oceanic lavas are thought to be derived from different sources within the Earth’s mantle, each with a distinct composition. Large-scale plate motions provide the primary mechanism for mixing these sources, yet the geochemical signature of lavas erupted at different mid-ocean ridges can still vary significantly. Geochemical variability is low where plate spreading rates are high, consistent with plate-scale mixing. However, slow-spreading centres, such as the Southwest Indian Ridge in the Indian Ocean, are also geochemically homogeneous, which is inconsistent with plate-scale mixing. Here we use numerical simulations of mantle flow to study mantle mixing at mid-ocean ridges, under conditions with variable plate length and spreading rate. Our simulations reveal that small-scale convection in the mantle contributes significantly to mantle mixing at slow spreading rates; faster plate velocities and smaller plates inhibit small-scale convection. We conclude that whereas fast-spreading ridge lavas are well mixed by plate-scale flow, slow-spreading ridge lavas are mixed by small-scale convection.

  14. Lessons for resource conservation from two contrasting small-scale fisheries.

    Science.gov (United States)

    Eriksson, Hampus; de la Torre-Castro, Maricela; Purcell, Steven W; Olsson, Per

    2015-04-01

    Small-scale fisheries present challenges to management due to fishers' dependency on resources and the adaptability of management systems. We compared social-ecological processes in the sea cucumber fisheries of Zanzibar and Mayotte, Western Indian Ocean, to better understand the reasons for resource conservation or collapse. Commercial value of wild stocks was at least 30 times higher in Mayotte than in Zanzibar owing to lower fishing pressure. Zanzibar fishers were financially reliant on the fishery and increased fishing effort as stocks declined. This behavioral response occurred without adaptive management and reinforced an unsustainable fishery. In contrast, resource managers in Mayotte adapted to changing fishing effort and stock abundance by implementing a precautionary fishery closure before crossing critical thresholds. Fishery closure may be a necessary measure in small-scale fisheries to preserve vulnerable resources until reliable management systems are devised. Our comparison highlighted four poignant lessons for managing small-scale fisheries: (1) diagnose the fishery regularly, (2) enable an adaptive management system, (3) constrain exploitation within ecological limits, and (4) share management responsibility. PMID:25238980

  15. Evaluation of external heat loss from a small-scale expander used in organic Rankine cycle

    International Nuclear Information System (INIS)

    With the scaling down of the Organic Rankine Cycle (ORC), the engine shaft power is not only determined by the enthalpy drop in the expansion process but also the external heat loss from the expander. Theoretical and experimental support in evaluating small-scale expander heat loss is rare. This paper presents a quantitative study on the convection, radiation, and conduction heat transfer from a kW-scale expander. A mathematical model is built and validated. The results show that the external radiative or convective heat loss coefficient was about 3.2 or 7.0 W/K.m2 when the ORC operated around 100 oC. Radiative and convective heat loss coefficients increased as the expander operation temperature increased. Conductive heat loss due to the connection between the expander and the support accounted for a large proportion of the total heat loss. The fitting relationships between heat loss and mean temperature difference were established. It is suggested that low conductivity material be embodied in the support of expander. Mattress insulation for compact expander could be eliminated when the operation temperature is around 100 oC. - Highlights: ? A close examination of external heat loss from a small expander is presented. ? Theoretical analysis and experimental test were conducted. ? The established formulas can be applied to other small ORC expanders. ? The results are useful in further research of small-scale ORC.f small-scale ORC.

  16. Resolving the Paradox of Oceanic Large-Scale Balance and Small-Scale Mixing

    Science.gov (United States)

    Marino, R.; Pouquet, A.; Rosenberg, D.

    2015-03-01

    A puzzle of oceanic dynamics is the contrast between the observed geostrophic balance, involving gravity, pressure gradient, and Coriolis forces, and the necessary turbulent transport: in the former case, energy flows to large scales, leading to spectral condensation, whereas in the latter, it is transferred to small scales, where dissipation prevails. The known bidirectional constant-flux energy cascade maintaining both geostrophic balance and mixing tends towards flux equilibration as turbulence strengthens, contradicting models and recent observations which find a dominant large-scale flux. Analyzing a large ensemble of high-resolution direct numerical simulations of the Boussinesq equations in the presence of rotation and no salinity, we show that the ratio of the dual energy flux to large and to small scales agrees with observations, and we predict that it scales with the inverse of the Froude and Rossby numbers when stratification is (realistically) stronger than rotation. Furthermore, we show that the kinetic and potential energies separately undergo a bidirectional transfer to larger and smaller scales. Altogether, this allows for small-scale mixing which drives the global oceanic circulation and will thus potentially lead to more accurate modeling of climate dynamics.

  17. 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 needslated to user needs

  18. Resolving the paradox of oceanic large-scale balance and small-scale mixing.

    Science.gov (United States)

    Marino, R; Pouquet, A; Rosenberg, D

    2015-03-20

    A puzzle of oceanic dynamics is the contrast between the observed geostrophic balance, involving gravity, pressure gradient, and Coriolis forces, and the necessary turbulent transport: in the former case, energy flows to large scales, leading to spectral condensation, whereas in the latter, it is transferred to small scales, where dissipation prevails. The known bidirectional constant-flux energy cascade maintaining both geostrophic balance and mixing tends towards flux equilibration as turbulence strengthens, contradicting models and recent observations which find a dominant large-scale flux. Analyzing a large ensemble of high-resolution direct numerical simulations of the Boussinesq equations in the presence of rotation and no salinity, we show that the ratio of the dual energy flux to large and to small scales agrees with observations, and we predict that it scales with the inverse of the Froude and Rossby numbers when stratification is (realistically) stronger than rotation. Furthermore, we show that the kinetic and potential energies separately undergo a bidirectional transfer to larger and smaller scales. Altogether, this allows for small-scale mixing which drives the global oceanic circulation and will thus potentially lead to more accurate modeling of climate dynamics. PMID:25839278

  19. Low cost, small scale processing technologies for production applications in various environments: Mass produced factories

    Energy Technology Data Exchange (ETDEWEB)

    Bramsiepe, C; Sievers, S; Seifert, T; Stefanidis, G D; Vlachos, Dion G.; Schnitzer, H; Muster, B; Brunner, C; Sanders, J P.M.; Bruins, M E; Schembecker, G

    2012-01-01

    The requirements for chemical and food production technologies will change in the future as a result of shorter time to market and increasing market volatility. Especially the rising use of renewable resources will require the implementation of flexible and fast to install small-scale production technologies. The increasing number of necessary apparatuses and their distributed operation, however, will constitute major challenges, both economically and procedurally. The proposed solution to face the economic challenge is modularization and standardization. For food production, dewatering represents a key issue. Thus, biomass processing should first be divided into small-scale water separation steps and then into further large-scale processing steps. As dewatering usually happens thermally and heat exchangers often benefit from the economies of scale, heat supply and energy consumption or heat transfer with little capital investment are further issues. Therefore, temperature levels should be decreased and the use of solar heat increased. For the production of biofuels and chemicals from biomass, process integration and process simplification are proposed to improve the efficacy of production equipment and processes. Choosing raw materials with molecular structures, similar to the desired chemical building block, will lower the need for heat exchange and make small-scale manufacturing of fuels and chemicals possible.

  20. 2012 THIN FILM AND SMALL SCALE MECHANICAL BEHAVIOR GRS/GRC, JULY 21-27, 2012

    Energy Technology Data Exchange (ETDEWEB)

    Balk, Thomas

    2012-07-27

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

  1. Persistence of small-scale anisotropies and anomalous scaling in a model of magnetohydrodynamics turbulence

    Science.gov (United States)

    Antonov, N. V.; Lanotte, A.; Mazzino, A.

    2000-06-01

    The problem of anomalous scaling in magnetohydrodynamics turbulence is considered within the framework of the kinematic approximation, in the presence of a large-scale background magnetic field. The velocity field is Gaussian, ?-correlated in time, and scales with a positive exponent ?. Explicit inertial-range expressions for the magnetic correlation functions are obtained; they are represented by superpositions of power laws with nonuniversal amplitudes and universal (independent of the anisotropy and forcing) anomalous exponents. The complete set of anomalous exponents for the pair correlation function is found nonperturbatively, in any space dimension d, using the zero-mode technique. For higher-order correlation functions, the anomalous exponents are calculated to O(?) using the renormalization group. The exponents exhibit a hierarchy related to the degree of anisotropy; the leading contributions to the even correlation functions are given by the exponents from the isotropic shell, in agreement with the idea of restored small-scale isotropy. Conversely, the small-scale anisotropy reveals itself in the odd correlation functions: the skewness factor is slowly decreasing going down to small scales and higher odd dimensionless ratios (hyperskewness, etc.) dramatically increase, thus diverging in the r-->0 limit.

  2. Small-scale Gradients of Charged Particles in the Heliospheric Magnetic Field

    Science.gov (United States)

    Guo, Fan; Giacalone, Joe

    2014-01-01

    Using numerical simulations of charged-particles propagating in the heliospheric magnetic field, we study small-scale gradients, or "dropouts," in the intensity of solar energetic particles seen at 1 AU. We use two turbulence models, the foot-point random motion model and the two-component model, to generate fluctuating magnetic fields similar to spacecraft observations at 1 AU. The turbulence models include a Kolmogorov-like magnetic field power spectrum containing a broad range of spatial scales from those that lead to large-scale field-line random walk to small scales leading to resonant pitch-angle scattering of energetic particles. We release energetic protons (20 keV-10 MeV) from a spatially compact and instantaneous source. The trajectories of energetic charged particles in turbulent magnetic fields are numerically integrated. Spacecraft observations are mimicked by collecting particles in small windows when they pass the windows at a distance of 1 AU. We show that small-scale gradients in the intensity of energetic particles and velocity dispersions observed by spacecraft can be reproduced using the foot-point random motion model. However, no dropouts are seen in simulations using the two-component magnetic turbulence model. We also show that particle scattering in the solar wind magnetic field needs to be infrequent for intensity dropouts to form.

  3. Factors Influencing the Choice of Management Strategy among Small-Scale Private Forest Owners in Sweden

    Directory of Open Access Journals (Sweden)

    Jeannette Eggers

    2014-07-01

    Full Text Available Half of the productive forest area in Sweden is owned by small-scale private forest owners. However, there is a lack of comprehensive information that would allow categorizing small-scale private forest owners according to their management strategy. In this study, we surveyed small-scale private forest owners in Sweden to determine the proportions who applied various management strategies. We analyzed the results using chi-square tests to identify the most relevant factors affecting the management strategy choices of individual forest owners. We found that “soft” factors, such as the importance of income from the forest, membership in a forest owners’ association, certification and an interest in and knowledge of forestry issues, had a stronger impact on the choice of management strategy than most “hard” factors related to the owner or the property, such as gender and distance between the owner’s residence and the property. However, property size was the most important factor and was associated with the importance of income derived from the forest and several other soft factors.

  4. Experimental approach for deep proteome measurements from small-scale microbial biomass samples.

    Science.gov (United States)

    Thompson, Melissa R; Chourey, Karuna; Froelich, Jennifer M; Erickson, Brian K; VerBerkmoes, Nathan C; Hettich, Robert L

    2008-12-15

    Many methods of microbial proteome characterizations require large quantities of cellular biomass (>1-2 g) for sample preparation and protein identification. Our experimental approach differs from traditional techniques by providing the ability to identify the proteomic state of a microbe from a few milligrams of starting cellular material. The small-scale, guanidine lysis method minimizes sample loss by achieving cellular lysis and protein digestion in a single-tube experiment. For this experimental approach, the freshwater microbe Shewanella oneidensis MR-1 and the purple non-sulfur bacterium Rhodopseudomonas palustris CGA0010 were used as model organisms for technology development and evaluation. A 2-D LC-MS/MS comparison between a standard sonication lysis method and the small-scale guanidine lysis techniques demonstrates that the guanidine lysis method is more efficient with smaller sample amounts of cell pellet (i.e., down to 1 mg). The described methodology enables deeper proteome measurements from a few milliliters of confluent bacterial cultures. We also report a new protocol for efficient lysis from small amounts of natural biofilm samples for deep proteome measurements, which should greatly enhance the emerging field of environmental microbial community proteomics. This straightforward sample boiling protocol is complementary to the small-scale guanidine lysis technique, is amenable for small sample quantities, and requires no special reagents that might complicate the MS measurements. PMID:19072265

  5. Experimental Approach for Deep Proteome Measurements from Small-Scale Microbial Biomass Samples.

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Melissa R [ORNL; Chourey, Karuna [ORNL; Froelich, Jennifer M. [Michigan State University, East Lansing; Erickson, Brian K [ORNL; Verberkmoes, Nathan C [ORNL; Hettich, Robert {Bob} L [ORNL

    2008-01-01

    Many methods of microbial proteome characterizations require large quantities of cellular biomass (> 1-2 g) for sample preparation and protein identification. Our experimental approach differs from traditional techniques by providing the ability to identify the proteomic state of a microbe from a few milligrams of starting cellular material. The small-scale, guanidine-lysis method minimizes sample loss by achieving cellular lysis and protein digestion in a single tube experiment. For this experimental approach, the freshwater microbe Shewanella oneidensis MR-1 and the purple non-sulfur bacterium Rhodopseudomonas palustris CGA0010 were used as model organisms for technology development and evaluation. A 2-D LC-MS/MS comparison between a standard sonication lysis method and the small-scale guanidine-lysis techniques demonstrates that the guanidine-lysis method is more efficient with smaller sample amounts of cell pellet (i.e. down to 1 mg). The described methodology would enable deep proteome measurements from a few milliliters of confluent bacterial cultures. We also report a new protocol for efficient lysis from small amounts of natural biofilm samples for deep proteome measurements, which should greatly enhance the emerging field of microbial community proteomics. This straightforward sample boiling protocol is complementary to the small-scale guanidine-lysis technique, is amenable for small sample quantities, and requires no special reagents that might complicate the MS measurements.

  6. 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 structural analysis was performed

  7. Small scale aspects of warm dark matter: Power spectra and acoustic oscillations

    International Nuclear Information System (INIS)

    We provide a semianalytic derivation of approximate evolution equations for density perturbations of warm dark matter candidates that decoupled while relativistic with arbitrary distribution functions, their solutions at small scales, and a simple numerical implementation that yields their transfer functions and power spectra. Density perturbations evolve through three stages: radiation domination when the particle is relativistic and nonrelativistic and matter domination. An early integrated Sachs-Wolfe effect during the first stage leads to an enhancement of density perturbations and a plateau in the transfer function for k fs, the free-streaming wave vector. An effective fluid description emerges at small scales which includes the effects of free streaming in initial conditions and inhomogeneities. The transfer function features warm dark matter acoustic oscillations at scales k > or approx. 2kfs. A simple analytic interpolation of the power spectra between large and small scales and a numerical implementation valid for arbitrary distribution functions is provided. As an application we study the power spectra for two models of sterile neutrinos with m?keV produced nonresonantly and compare our results to those obtained from Boltzmann codes.

  8. Manual for development of small scale hydroelectric projects by public entities

    Energy Technology Data Exchange (ETDEWEB)

    1981-03-01

    This manual is designed to provide guidance to towns, cities, counties and other political subdivisions which are interested in undertaking or participating in small scale hydroelectric (SSH) development within or close to their territorial boundaries. The manual is primarily directed to those political subdivisions which either own or have access to a site, are interested in exploring the prospects for development of the site and do not have longstanding experience in the electric power development. For purposes of this manual a small scale hydroelectric project is a project of 25 to 30 MWs or less and utilizes an existing dam or structure or utilizes the site characteristics of partially breached dams or structures. As the reader will observe from the discussion that follows, several incentives under federal and state law have been implemented which favor small scale hydroelectric development at existing sites. This manual is designed to assist political subdivisions in taking advantage of these incentives and devising strategies for development. The manual will provide information to political subdivisions as to what to expect in the development process and the kinds of informed questions to ask of paid advisers. The manual, however, cannot be and should not be used as a substitute for competent advice and assistance from experienced lawyers, engineers, accountants and financing experts.

  9. Running with BICEP2: implications for small-scale problems in CDM

    Science.gov (United States)

    Garrison-Kimmel, Shea; Horiuchi, Shunsaku; Abazajian, Kevork N.; Bullock, James S.; Kaplinghat, Manoj

    2014-10-01

    The BICEP2 results, when interpreted as a gravitational wave signal and combined with other cosmic microwave background data, suggest a roll-off in power towards small scales in the primordial matter power spectrum. Among the simplest possibilities is a running of the spectral index. Here we show that the preferred level of running alleviates small-scale issues within the ?CDM model, more so even than viable WDM models. We use cosmological zoom-in simulations of a Milky Way-sized halo along with full-box simulations to compare predictions among four separate cosmologies: a BICEP2-inspired running index model (?s = -0.024), two fixed-tilt ?CDM models motivated by Planck, and a 2.6 keV thermal WDM model. We find that the running BICEP2 model reduces the central densities of large dwarf-sized haloes (Vmax ˜ 30-80 km s-1) and alleviates the too-big-to-fail problem significantly compared to our adopted Planck and WDM cases. Further, the BICEP2 model suppresses the count of small subhaloes by ˜50 per cent relative to Planck models, and yields a significantly lower `boost' factor for dark matter annihilation signals. Our findings highlight the need to understand the shape of the primordial power spectrum in order to correctly interpret small-scale data.

  10. Magnetohydrodynamic Kink Waves in Nonuniform Solar Flux Tubes: Phase Mixing and Energy Cascade to Small Scales

    Science.gov (United States)

    Soler, Roberto; Terradas, Jaume

    2015-04-01

    Magnetohydrodynamic (MHD) kink waves are ubiquitously observed in the solar atmosphere. The propagation and damping of these waves may play relevant roles in the transport and dissipation of energy in the solar atmospheric medium. However, in the atmospheric plasma dissipation of transverse MHD wave energy by viscosity or resistivity needs very small spatial scales to be efficient. Here, we theoretically investigate the generation of small scales in nonuniform solar magnetic flux tubes due to phase mixing of MHD kink waves. We go beyond the usual approach based on the existence of a global quasi-mode that is damped in time due to resonant absorption. Instead, we use a modal expansion to express the MHD kink wave as a superposition of Alfvén continuum modes that are phase mixed as time evolves. The comparison of the two techniques evidences that the modal analysis is more physically transparent and describes both the damping of global kink motions and the building up of small scales due to phase mixing. In addition, we discuss that the processes of resonant absorption and phase mixing are closely linked. They represent two aspects of the same underlying physical mechanism: the energy cascade from large scales to small scales due to naturally occurring plasma and/or magnetic field inhomogeneities. This process may provide the necessary scenario for efficient dissipation of transverse MHD wave energy in the solar atmospheric plasma.

  11. Linking birds, fields and farmers.

    Science.gov (United States)

    Swagemakers, Paul; Wiskerke, Han; Van Der Ploeg, Jan Douwe

    2009-05-01

    The dramatic decline in the presence of farmland birds during recent decades has provoked much attention in agri-environmental policy and ecological research. However, the still limited understanding of the socio-economical mechanisms that govern the decline in bird presence hampers the formulation of effective adjustments in land-use and farming practices that could support the return of birds to farmland, i.e. the required fine-tuning of management practices. As a consequence, the existing agri-environmental schemes that offer financial compensation to farmers for implementing generally simple and rather crude measures to stimulate the presence of birds have been limited in their effectiveness and subject to much debate. The objective of this paper is to provide a sociological appraisal of farmers' experiences with meadow bird protection in a mainly dairy farming area in the Netherlands. The methodology combined visual map analysis, surveys, interviews with farmers and experts, and monitoring farmers' discussions. The results allowed an assessment of (i) farmers' views on historical changes in bird numbers in the area and the current distribution of bird nests, (ii) locally adjusted, fine-tuned management practices that were considered to be promising for protecting bird nests, (iii) the importance of farm management with 'an eye for birds', i.e. farmers and/or birdwatchers paying additional attention to the presence of nests and chicks before carrying out farming activities, and (iv) the views of key experts in the socio-institutional network in the case study area. The paper concludes that there are various promising options for fine-tuning farm management so it offers better bird protection, but it is expected that such measures will predominantly be adopted on less intensively managed farms. PMID:19111966

  12. Farmers’ Perception of Precision Farming Technology among Hungarian Farmers

    Directory of Open Access Journals (Sweden)

    Enik? Lencsés

    2014-11-01

    Full Text Available Many technologies have appeared in agriculture to reduce the harmful effects of chemical use. One of these technologies is precision farming technology. Precision farming technology should not be considered as only the latest plant production technology or only a new agro-management tool. It is achieved only when the results of electronics and IT equipment are realized in the variable rate treatments zone-by-zone. The advantages and disadvantages of this technology highly depend on the heterogeneity of soil, the knowledge and attitude of the manager and the staff. This is the reason why opinions about the technology effects are so wide. This paper shows the results of the investigation based on interviews about the adoption and knowledge of precision farming technology among Hungarian crop producers. This technology is mostly used by farms over 300 hectares with young farmers. The most characteristic elements were precision fertilization and tractor guidance. The survey examined three groups of farmers with respect to whether they apply precision farming elements or not. We refer to them as “users”, “planners” and “non-users”. According to the survey, the opinions of the “user” and the “non-user” groups of farmers are not significantly different regarding the impacts of precision farming technology (the main advantages were the change in yield quantity, chemical usage and income. Furthermore, the opinions of the farmers regarding the changes in variable costs resulting from the adoption of precision farming technology were also examined (measured in percent. Box-plot analysis was used for this examination. According to the opinion of the “user” group of farmers, the highest cost savings occurred in fertilizer and herbicide costs.

  13. Extending acoustic data measured with small-scale supersonic model jets to practical aircraft exhaust jets

    Science.gov (United States)

    Kuo, Ching-Wen

    2010-06-01

    Modern military aircraft jet engines are designed with variable geometry nozzles to provide optimum thrust in different operating conditions within the flight envelope. However, the acoustic measurements for such nozzles are scarce, due to the cost involved in making full-scale measurements and the lack of details about the exact geometry of these nozzles. Thus the present effort at The Pennsylvania State University and the NASA Glenn Research Center, in partnership with GE Aviation, is aiming to study and characterize the acoustic field produced by supersonic jets issuing from converging-diverging military style nozzles. An equally important objective is to develop a scaling methodology for using data obtained from small- and moderate-scale experiments which exhibits the independence of the jet sizes to the measured noise levels. The experimental results presented in this thesis have shown reasonable agreement between small-scale and moderate-scale jet acoustic data, as well as between heated jets and heat-simulated ones. As the scaling methodology is validated, it will be extended to using acoustic data measured with small-scale supersonic model jets to the prediction of the most important components of full-scale engine noise. When comparing the measured acoustic spectra with a microphone array set at different radial locations, the characteristics of the jet noise source distribution may induce subtle inaccuracies, depending on the conditions of jet operation. A close look is taken at the details of the noise generation region in order to better understand the mismatch between spectra measured at various acoustic field radial locations. A processing methodology was developed to correct the effect of the noise source distribution and efficiently compare near-field and far-field spectra with unprecedented accuracy. This technique then demonstrates that the measured noise levels in the physically restricted space of an anechoic chamber can be appropriately extrapolated to represent the expected noise levels at different noise monitoring locations of practical interest. With the emergence of more powerful fighter aircraft, supersonic jet noise reduction devices are being intensely researched. Small-scale measurements are a crucial step in evaluating the potential of noise reduction concepts at an early stage in the design process. With this in mind, the present thesis provides an acoustic assessment methodology for small-scale military-style nozzles with chevrons. Comparisons are made between the present measurements and those made by NASA at moderate-scale. The effect of chevrons on supersonic jets was investigated, highlighting the crucial role of the jet operating conditions on the effects of chevrons on the jet flow and the subsequent acoustic benefits. A small-scale heat simulated jet is investigated in the over-expanded condition and shows no substantial noise reduction from the chevrons. This is contrary to moderate-scale measurements. The discrepancy is attributed to a Reynolds number low enough to sustain an annular laminar boundary layer in the nozzle that separates in the over-expanded flow condition. These results are important in assessing the limitations of small-scale measurements in this particular jet noise reduction method. Lastly, to successfully present the results from the acoustic measurements of small-scale jets with high quality, a newly developed PSU free-field response was empirically derived to match the specific orientation and grid cap geometry of the microphones. Application to measured data gives encouraging results validating the capability of the method to produce superior accuracy in measurements even at the highest response frequencies of the microphones.

  14. Responding to Globalization: Impacts of Certification on Colombian Small-Scale Coffee Growers

    Directory of Open Access Journals (Sweden)

    Ximena Rueda

    2013-09-01

    Full Text Available Eco-certification of food and other agricultural products has been promoted as a way of making markets work for sustainability. Certification programs offer a price premium to producers who invest in more sustainable practices. The literature on the impacts of certification has focused primarily on the economic benefits farmers perceive from participating in these schemes. These benefits, however, are often subject to price variability, offering only a partial explanation of why farmers join and stay in certification programs. We evaluated the potential of the Rainforest Alliance certification program to foster more resilient social-ecological systems in the face of globalization. Using the case of Santander, Colombia, and a pair-based comparison of 86 households to effectively produce a robust counterfactual, we showed that certification provides important environmental benefits, while improving the well-being of farmers and their communities. Furthermore, the study showed that price premiums are only one of many elements defining the success of certification, particularly important for motivating farmers to join, but less so to explain retention and upgrading. The case of Colombian coffee growers illustrates how the connections between local social-ecological systems and larger global forces can produce more sustainable livelihoods and land uses.

  15. 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)

    Md. Mujibur Rahman

    2002-01-01

    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.

  16. Senior Farmers' Market Nutrition Program

    Science.gov (United States)

    ... coupons that can be exchanged for eligible foods (fruits, vegetables, honey, and fresh-cut herbs) at farmers' markets, roadside stands, and community ... are available through the SFMNP? Fresh, nutritious, unprocessed fruits, ... honey, and fresh-cut herbs can be purchased with SFMNP benefits. State ...

  17. Eating Healthy

    Science.gov (United States)

    Ms. Kellersberger

    2011-12-12

    Learn about different healthy diets and exercises that can help your body achieve mental and physical wellness. It's time to learn about what we can do to help us stay healthy and fit! Explore these following websites in order to learn more about healthy diets, good nutrition, and great exercises: Dining Decisions Nutrients Your Body Needs Pyramid Blast Off Now that you've finished exploring these resources, answer the following questions: 1. Think about you're average daily ...

  18. Healthy Diet

    Science.gov (United States)

    Mrs. Parker

    2009-09-28

    This project will explain the importance of a balanced diet as well as learn nutrition facts to help them apply a healthy diet in their everyday lives Eating good foods is very important to living a healthy life. Click on 'food groups' pyramid below and learn about what types of food should be in your daily diet. Food groups 1. What makes a certain food healthy? 2. Do you eat the foods from the pyramid on a regular ...

  19. Farmer Experience of Pluralistic Agricultural Extension, Malawi

    Science.gov (United States)

    Chowa, Clodina; Garforth, Chris; Cardey, Sarah

    2013-01-01

    Purpose: Malawi's current extension policy supports pluralism and advocates responsiveness to farmer demand. We investigate whether smallholder farmers' experience supports the assumption that access to multiple service providers leads to extension and advisory services that respond to the needs of farmers. Design/methodology/approach: Within a…

  20. Farmers' Attitudes and Behavior toward Sustainable Agriculture.

    Science.gov (United States)

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

    1996-01-01

    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…