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

International Nuclear Information System (INIS)

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)

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

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The Food Crop Development Project (FCDP) was introduced with the aim of improving farm incomes, household food security, nutrition and reducing poverty among small-scale farmers. This study sought to find answers to the questions of whether the project improved farmers’ access to credit, improved maize output or whether small-scale maize farmers adopted the improved maize production practices and how it impacted on maize production. Descriptive survey was conducted and using multi-stage ran...

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

2012-01-01

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Economic Efficiency of Small Scale Farmers in Ogun State, Nigeria  

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

Adeyemo, R.

2010-01-01

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

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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.

Sylvester Mpandeli

2014-03-01

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

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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.

Enock S. Ugulumu

2013-04-01

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

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Full Text Available 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 agricultural zones-central, eastern, northern and western. Data were analyzed using two-way factorial analysis of variance (ANOVA and mean separation was done at 5% probability level. Results revealed that there was significant difference (pa on crop production was perceived to be serious and it was significantly higher than the impacts of goat (1.92b, sheep (1.78c and domestic fowls (1.28d. The implication of this is that cattle were the most destructive livestock animals while domestic fowls were the least. At the zonal level, result revealed that the crop farmers in the eastern and western agricultural zones of Abuja felt the impacts of the grazing animals more than crop farmers in the other two zones. Based on the results, the paper recommended that government should map out grazing routes and/or educate and encourage the livestock farmers to adopt intensive system of management to minimize clashes and the damages that occur.

Ajah Julius

2012-01-01

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Risk of Resource Failure and Toolkit Variation in Small-Scale Farmers and Herders  

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Recent work suggests that global variation in toolkit structure among hunter-gatherers is driven by risk of resource failure such that as risk of resource failure increases, toolkits become more diverse and complex. Here we report a study in which we investigated whether the toolkits of small-scale farmers and herders are influenced by risk of resource failure in the same way. In the study, we applied simple linear and multiple regression analysis to data from 45 small-scale food-producing gr...

Collard, Mark; Ruttle, April; Buchanan, Briggs; O’brien, Michael

2012-01-01

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

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

Julio César Vinay-Vadillo

2012-11-01

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

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Using data from 104 small scale poultry farmers in Oyo state of Nigeria, this study examined the role of poultry production in rural poverty reduction. The results show that majority of the farmers were male (87 percent), married (87 percent), having family size of 5 to 7 persons (53 percent), above 44 years of age with farming experience of 7.5 years on average and with formal education (95 percent). The average net farm income (NFI) is N788,164 per annum indicating that, the business is wor...

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

2012-01-01

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

Scientific Electronic Library Online (English)

Full Text Available SciELO South Africa | Language: English Abstract in english This study determined the access, worth assessment and use of information by small-scale farmers in Oyo State. The study described socio-economic characteristics of small-scale cassava farmers; ascertained information access point preferences and analyzed information worth assessment. A multi stage [...] sampling was used to select 360 respondents and data were collected through pre-tested and face validated questionnaire with a reliability coefficient of 0.88. The results show 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

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

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

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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.

Job N. Nmadu

2013-04-01

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

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

Patrick Van Damme

2011-05-01

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

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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...

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

2005-01-01

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

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Bungoma County is one of the areas in Kenya where maize is produced on small-scale basis; however, the County isfacing soil nutrient depletion due to continuous and unsustainable cultivation of land. Various interventions have sensitized farmers into adopting organic soil management techniques of enhancing soil fertility and upholding environmental sustainability. The study was aimedatestablishing the most preferred organic soil managementtechniques among farmers and the factors influencing t...

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

2012-01-01

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

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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.

M.B.R. Chowdhury

2003-01-01

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

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

Oscar I. Ayuya

2012-07-01

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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)

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…

Muthoni Thuo, Caroline

2011-01-01

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

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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.

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

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

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

Jonathan Kuje Yohanna

2011-06-01

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

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

Buch-Hansen, Mogens

2012-01-01

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

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

Sharon Groenmeyer

2013-04-01

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

Science.gov (United States)

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 (log10) 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. PMID:24140681

Huong, Luu Quynh; Madsen, Henry; Anh, Le Xuan; Ngoc, Pham Thi; Dalsgaard, Anders

2014-02-01

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

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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 compe...

Ejaz Ashraf; Abu Bakar Muhammad Raza; Samiullah; Muhammad Younis

2012-01-01

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Evaluation of the appropriateness of certain grain production technologies for small-scale farmers  

Scientific Electronic Library Online (English)

Full Text Available SciELO South Africa | Language: English Abstract in english The paper suggests a combination of both modern, high-input technologies and low-input technologies in a context based technology development approach. These technologies are: improved maize varieties; row planting; legumes in the cropping system; reduced tillage practices and weed control. Although [...] some adaptations are needed, none of the innovations in the program failed the test of appropriateness completely. According to the findings Open Pollinated Varieties (OPV's), although intensively promoted, were only preferred by 35% of the farmers while hybrid seed was preferred by 59% of the farmers. The majority of farmers (63%) indicated that they do plant maize in rows with a mechanised planter; despite high labour costs 59% of farmers still control weeds by hand and 61% of the respondents do realise the economic advantage of reduced tillage practices but still does not implement the practices. The strong linkages between all role players and active farmer participation are probably the most important reasons for the fact that farmers are still enthusiastic and eager to continue with the program.

A.P.N., du Toit; E.A., Nemadodzi.

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The impact and accessibility of agricultural credit : a case study of small-scale farmers in the Northern Province of South Africa  

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This study is an exploratory analysis of the impact and accessibility of formal agricultural credit to small-scale farmers, based on data collected from a sample of farmers in two regions of South Africa’s Limpopo Province. The main aims of the research were to: -- Determine the impact of credit and its shadow price. -- Investigate the efficiency of the rural financial market. -- Determine the characteristics and factors that influence the accessibility of credit in the small-scale farming ...

Spio, Kojo

2002-01-01

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

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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

Ajah Julius

2014-02-01

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

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

P.J. Masika

2012-07-01

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

Directory of Open Access Journals (Sweden)

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

Majory Ongie Meliko

2011-09-01

29

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

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

D. A. Iyai

2011-09-01

30

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

Directory of Open Access Journals (Sweden)

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.

Ejaz Ashraf

2012-12-01

31

Comparative Analysis of Allocative Efficiency in Input use by Credit and Non Credit User Small Scale Poulty Farmers in Delta State, Nigeria  

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Full Text Available This study examined the relative allocative efficiencies in input use by credit user and non credit user small scale poultry farmers in Delta State, Nigeria. Relative elasticities of production and returns to scale of the defined poultry farmers were examined. Primary data were collected from a random sample of 108 small scale poultry farmers consisting of 54 credit users and 54 non credit users. A stochastic frontier production function model was used to analyse the data. Results of the findings indicate that none of the poultry farmer groups allocated any production input optimally. All the variables entered in the model were significant for credit and non credit users except drugs and veterinary services which was not significant for non credit user poultry farmers. On the whole, the credit user poultry farmers over utilized (Kij1 feed input as well as drugs and veterinary services. The non credit user farmers over utilized (Kij1 feed input. It is therefore the recommendation of this study that economic policies and programmes such as the Delta state microcredit programme should be strengthened so as to improve access to credit and enhance efficiency in the use of resources by small scale poultry farmers.

P.C. Ike

2011-11-01

32

The impact and accessibility of agricultural credit : a case study of small-scale farmers in the Northern Province of South Africa  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This study is an exploratory analysis of the impact and accessibility of formal agricultural credit to small-scale farmers, based on data collected from a sample of farmers in two regions of South Africas Limpopo Province. The main aims of the research were to: -- Determine the impact of credit and its shadow price. -- Investigate the efficiency of the rural financial market. -- Determine the characteristics and factors that influence the accessibility of credit in the s...

Spio, Kojo

2005-01-01

33

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

In general, small-scale vegetable farmers experience problems in improving the safety and quality of vegetables for supplying high-class consumers in modern retailers. Farmer Group and/or Cooperative (FGC) should be able to assist its members to meet the relevant provisions of modern retail on product specifications, delivery terms, and internal business requirements. This study proposed an agri-food supply chain (ASC) model that involves the corporate social responsibility (CSR) activities t...

Wahyudi Sutopo; Muh. Hisjam; Yuniaristanto

2012-01-01

34

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

35

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

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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.

B.A.J. du Plessis

2012-07-01

36

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  

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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.

Oscar I. Ayuya

2011-04-01

37

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

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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.

N.R. Bryson

2012-07-01

38

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

Scientific Electronic Library Online (English)

Full Text Available SciELO South Africa | Language: English Abstract in english The Elundini program included small-scale livestock farmers in the Eastern Cape, South Africa. The program's data analyses and the impact on farmers and the economy were evaluated. Since program inception, sheep mortality decreased from >20% to 3%. Lamb weaning rates were approximately one lamb for [...] every two ewes (50%). Farmers' annual income increased from R650.00 to R20,956.00 (R1.00~ $0.15) with a total net gain of >R56 million for the region. Strict mentor management 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.

A J, Jordaan.

39

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

Directory of Open Access Journals (Sweden)

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

Wahyudi Sutopo

2012-04-01

40

FACTORS INFLUENCING DECISIONS FOR USING OUTSIDE FUNDS FOR FARM INVESTMENTS AND PROPRIETOR WITHDRAWALS BY SMALL-SCALE FARMERS IN ABIA STATE, NIGERIA  

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Full Text Available This study on factors influencing decisions for using outside funds for Farm investments and for proprietor withdrawals was carried out among rural small-scale farm households in Abia state, Nigeria. A cross-sectional survey of ninety (90 rural farm households of multi-type (varied enterprises was carried out using cluster random sampling technique in three communities, each chosen from one of the three agricultural zones of the state. Results indicated rural household level variables that positively influenced decisions to source farm investment fund to include level of education, gender, membership of cooperative society, interest charge, land acquisition method, and ease of getting loan. Other factors that negatively influenced decisions include farming as major occupation, household savings, household size, and distance of farmers’ home to source of credit. Proprietor withdrawal decisions were positively influenced by household level variables like taking farming as major occupation, payment of school fees for children of farmers, and amount of credit so far repaid by a farm household. Other factors namely household size, being member of cooperative society or savings group, interest charges on loan, off-farm income, and household savings had negative influences on proprietor withdrawal decisions. We recommended that small-scale farmers should not borrow their start-up capital from outside their households but as their farm businesses stabilize, they could decide to take loans from outside to cover their working capital and/or expand their farms and be prepared to repay such loans according to contractual agreements.

Chriso O. EMEROLE

2013-08-01

 
 
 
 
41

[Maximization of economic yield, minimum cost optimal diets and cultivation diversification for small scale farmers of the highland region of Guatemala].  

Science.gov (United States)

The present study was conducted as part of an evaluation of the economic and nutritional effects of a crop diversification program for small-scale farmers in the Western highlands of Guatemala. Linear programming models are employed in order to obtain optimal combinations of traditional and non-traditional food crops under different ecological conditions that: a) provide minimum cost diets for auto-consumption, and b) maximize net income and market availability of dietary energy. Data used were generated by means of an agroeconomic survey conducted in 1983 among 726 farming households. Food prices were obtained from the Institute of Agrarian Marketing; data on production costs, from the National Bank of Agricultural Development in Guatemala. The gestation periods for each crop were obtained from three different sources, and then averaged. The results indicated that the optimal cropping pattern for the minimum-cost diets for auto consumption include traditional foods (corn, beans, broad bean, wheat, potato), non-traditional foods (carrots, broccoli, beets) and foods of animal origin (milk, eggs). A significant number of farmers included in the sample did not have sufficient land availability to produce all foods included in the minimum-cost diet. Cropping patterns which maximize net incomes include only non-traditional foods: onions, carrots, broccoli and beets for farmers in the low highland areas, and raddish, broccoli, cauliflower and carrots for farmers in the higher parts. Optimal cropping patterns which maximize market availability of dietary energy include traditional and non-traditional foods; for farmers in the lower areas: wheat, corn, beets, carrots and onions; for farmers in the higher areas: potato, wheat, raddish, carrots and cabbage. PMID:2490893

Alarcón, J A; Immink, M D; Méndez, L F

1989-12-01

42

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

Science.gov (United States)

Technical and socio-economic characteristics are known to determine different types of fishers and their livelihood strategies. Faced with declining fish and water resources, small-scale fisheries engage into transformations in livelihood and fishing practices. The paper is an attempt to understand these changes and their socio-economic patterns, in the case of Singkarak Lake in West Sumatra, Indonesia. Based upon the hypothesis that riparian communities have diverse, complex yet structured and dynamic livelihood systems, the paper's main objective is to study, document and model the actual diversity in livelihood, practices and performance of inland small-scale fisheries along the Singkarak Lake, to picture how households are adapted to the situation, and propose an updated, workable model (typology) of those for policy. Principal component analysis and cluster analysis were used to develop a typology of fishing households. The results show that small-scale fishers can be classified into different types characterized by distinct livelihood strategies. Three household types are identified, namely "farming fishers" households (type I, 30 %), "fishing farmers" households (type II, 30 %), and "mainly fishers" households (type III, 40 %). There are significant differences among these groups in the number of boats owned, annual fishing income, agriculture income and farming experience. Type I consists of farming fishers, well equipped, with high fishing costs and income, yet with the lowest return on fishing assets. They are also landowners with farming income, showing the lowest return on land capital. Type II includes poor fishing farmers, landowners with higher farming income; they show the highest return on land asset. They have less fishing equipment, costs and income. Type III (mainly fishers) consists of poorer, younger fishers, with highest return on fishing assets and on fishing costs. They have little land, low farming income, and diversified livelihood sources. The nature of their livelihood strategies is discussed for each identified group. This helps to understand the complexity and diversity of small-scale fishers, particularly in the study area which is still poorly known. This paper concludes with policy implication and possible management initiatives for environmentally prudent policy aiming at improvement of fishers' livelihood. PMID:23665756

Yuerlita; Perret, Sylvain Roger; Shivakoti, Ganesh P

2013-07-01

43

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

For many small producers in developing countries coffee is a major income source. However, the coffee market is characterized by high price volatility and increased power concentration among buyers in consuming countries. Due to the very low international coffee prices during the recent coffee crisis and an increased demand among consumers for healthy and ethical products as well as for high quality, interest in standards and certification has increased substantially in coffee producing and c...

Kiemen, Anna; Beuchelt, Tina

2010-01-01

44

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

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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.

Ofuoku, A. O. U.

2014-03-01

45

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  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Kaati, Patrik

2011-01-01

46

Designing Agricultural Development Projects for the Small Scale Farmers: Some Lessons from the World Bank Assistance Small Holder Oil Palm Development Scheme in Nigeria  

Science.gov (United States)

The study was carried out to investigate farmers reasons for intercropping their oil palm farms with food and other cash crops rather than the sole oil palm planting arrangement specified for participation in the World Bank Assistance Smallholder Oil Palm development project financed during the 1975-83 period. The study was conducted at the Ekuku-Agbor Tree Crop Unit Zone (to the East) and Mosogar Tree Crop Unit Zone (to the Southwest) of the old Bendel State of Nigeria. A total of 35 oil palm farmers were randomly selected from each zone for the study. The study tried to identify the size of oil palm cultivated, types of food and cash crops planted and the proportion consumed and sold and the sufficiency of labour for various farm activities. The study showed that the average oil palm farm size at Ekuku-Agbor zone was smaller (about 1.57 ha) and more fragmented while for Mosogar zone it was 2.28 ha. However a greater percentage (over 65%) of the farms at both locations were within 0.01-2.00 ha farm size range which could be said to be relatively small. The study revealed that among other factors the farmers desire to ensure adequate family food needs which equates to food security and some cash to meet regular family financial needs necessitated their intercropping of the oil palm farms. Others include the need to maximize the returns from the use of labour which they considered a major limiting factor in farm maintenance and to take advantage of the relative high unit price of cassava and its products that prevailed then by cultivating on any available land space including the palm plantations and thereby increasing their farm income.

Orewa, S. I.

47

Small scale optics  

CERN Document Server

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

Yupapin, Preecha

2013-01-01

48

Small scale windmill  

Science.gov (United States)

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.

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

2007-01-01

49

Sustainable Small-Scale Agriculture in Semi-Arid Environments  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

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

2011-01-01

50

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

Directory of Open Access Journals (Sweden)

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

Kaniz Quamrun Nahar Chhabi

2010-01-01

51

Sustainable Small-Scale Agriculture in Semi-Arid Environments  

Directory of Open Access Journals (Sweden)

Full Text Available 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. We use the archaeological and paleoclimatic records from A.D. 900-1600 in two regions of the American Southwest to explore the nature of variation in the availability of water for crops, and the strategies that enhanced the resilience of prehistoric agricultural production to climatic variation. Drawing on information concerning contemporary small-scale farming in semi-arid environments, we then suggest that the risk coping and mitigation strategies that have endured for millennia are relevant to enhancing the resilience of contemporary farmers' livelihoods to environmental and economic perturbations.

Scott Ingram

2011-03-01

52

Thai indigenous cattle production provide a sustainable alternative for the benefit of smallscale farmers, healthy food, and the environment  

International Nuclear Information System (INIS)

In Thailand, there are 5.66 million Thai indigenous cattle and their crossbred derivatives (1.76 million cows). The Department of Livestock Development (DLD) has a policy to conserve and use Thai indigenous cattle as the genetic base for establishing and developing new breeds of beef cattle. The objectives of this study were to study the production performance, carcass quality, healthy food production, economic potential, and environmental impacts of four breeds of Thai indigenous cattle (Kow-Lamphun, Kho-Esarn, Kho-Lan, and Kho-Chon cattle). Data were collected from two studies: i) 1 220 cattle from an experimental trial in DLD part, and ii) 390 cattle kept by smallholders in Northern, Northeastern, Central, and Southern parts of Thailand between October 2004 and September 2008. Data were adjusted by group, location, month, and year to analyse for the above parameters. Kho-Lan and Kho-Esarn cattle had the highest weaning weight and preweaning daily weight gains while Kow-Lamphun cattle had the highest Omega 3 (8.98%) and conjugated linoleic acid (CLA) levels in their meat (0.02%), and produced the highest net incomes (306 915.80 Baht/y). Through the conservation and use policies of the DLD, Thai indigenous cattle provided various advantages for farmers, consumers, and environment. (author)

53

Small-scale-field Dynamo  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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

Gruzinov, A.; Cowley, S.; Sudan, R.

1996-01-01

54

Method and system for small scale pumping  

Science.gov (United States)

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

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

2010-01-26

55

Biomass for energy - small scale technologies  

Energy Technology Data Exchange (ETDEWEB)

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

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

1997-12-31

56

Small scale structure on cosmic strings  

International Nuclear Information System (INIS)

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

57

Productivity and Profitability Layer Chicken Farm Using Small Scale Feed Mill Production in Sidrap Regency, South Sulawesi, Indonesia  

Directory of Open Access Journals (Sweden)

Full Text Available The objective of this research was to determine differences in productivity and profitability of layer poultry farm that used small scale feed mill production quality Indonesia National Standard (SNI and not based on SNI. The research survey was conducted to 30 layer farmers in Sidrap district that used feed produced by small scale factory by interview and observation. Primary and secondary data obtained were used to answer the research objective. Respondences characteristic, productivity, revenue, production costs and income were recorded for two months. Descriptive statistic and one sample t-test were used to analyze the data. Layer chicken farmer that used small scale feed mill produced generally raising chickens with business scale less than 5,000 chickens. Quality of productivity and productivity of layer chicken farm that used small scale mini feed mill produced was suited to SNI, significantly different (p>0.01 compared to one that wasnt based on SNI.

Irmasusanti

2013-01-01

58

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

Directory of Open Access Journals (Sweden)

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

Udom, I. J.

2010-12-01

59

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...

60

Integrated Approach for Improving Small Scale Market Oriented Dairy Systems in Pakistan: Economic Impact of Interventions  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The International Atomic Energy Agency (IAEA) launched a Coordinated Research Program in 10 developing countries including Pakistan involving small scale market oriented dairy farmers to identify and prioritize the constraints and opportunities in the selected dairy farms, develop intervention strategies and assess the economic impact of the intervention. The interventions in animal health (control of mastitis at sub-clinical stage and reduction in calf mortality), nutrition (balanced feed) r...

Ghaffar, A.

2010-01-01

 
 
 
 
61

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.)

62

Galaxy alignment on large and small scales  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 hy...

Kang, X.; Lin, W. P.; Wang, Y. O.; Dutton, A.; Maccio?, A.

2014-01-01

63

Small-Scale Biomass Power Generation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The aim of the present work is to provide a full overview on small scale technologies regarding biomass exploitation (particularly woody one) for power generation, in order to define the most interesting solutions from a thermodynamic and economic point of view. Existing configurations or those which are expected to be potentially available on the market in the near future have been considered. Three plant sizes have been focused: 100 kWel, 1 MWel and 5 MWel. Internal combustion engines (ICE)...

Carrara, Samuel

2010-01-01

64

Small-scale hydro power in Finland  

International Nuclear Information System (INIS)

At present there are around 150 operating small-scale hydro power plants in Finland, the power generating capacity of which varies between 50 and 1000 kW. The annual output in terms of produced energy is about 270 GWh which accounts for only 0.5 % of the total consumption of electricity. The plants are mainly owned by electricity distributing companies and industry. There are numerous old dams and abandoned small hydro power stations, once used as power source for flour mills and saw mills. The role of overall energy economics is reviewed in this article, as well as the increase potential for small-scale hydro power and the international cooperation in this field. The potential for small-scale hydro power in Finland has been estimated to be 370 MW in 1580 falls, of which 45 MW is used at 150 stations. Easily exploitable sites, usually with abandoned station or dam were calculated to be around 80 MW, corresponding to an annual energy output at 350 GWh

65

Small-Scale High-Performance Optics  

Energy Technology Data Exchange (ETDEWEB)

Historically, high resolution, high slew rate optics have been heavy, bulky, and expensive. Recent advances in MEMS (Micro Electro Mechanical Systems) technology and micro-machining may change this. Specifically, the advent of steerable sub-millimeter sized mirror arrays could provide the breakthrough technology for producing very small-scale high-performance optical systems. For example, an array of steerable MEMS mirrors could be the building blocks for a Fresnel mirror of controllable focal length and direction of view. When coupled with a convex parabolic mirror the steerable array could realize a micro-scale pan, tilt and zoom system that provides full CCD sensor resolution over the desired field of view with no moving parts (other than MEMS elements). This LDRD provided the first steps towards the goal of a new class of small-scale high-performance optics based on MEMS technology. A large-scale, proof of concept system was built to demonstrate the effectiveness of an optical configuration applicable to producing a small-scale (< 1cm) pan and tilt imaging system. This configuration consists of a color CCD imager with a narrow field of view lens, a steerable flat mirror, and a convex parabolic mirror. The steerable flat mirror directs the camera's narrow field of view to small areas of the convex mirror providing much higher pixel density in the region of interest than is possible with a full 360 deg. imaging system. Improved image correction (dewarping) software based on texture mapping images to geometric solids was developed. This approach takes advantage of modern graphics hardware and provides a great deal of flexibility for correcting images from various mirror shapes. An analytical evaluation of blur spot size and axi-symmetric reflector optimization were performed to address depth of focus issues that occurred in the proof of concept system. The resulting equations will provide the tools for developing future system designs.

WILSON, CHRISTOPHER W.; LEGER, CHRIS L.; SPLETZER, BARRY L.

2002-06-01

66

Why small-scale alternatives won'  

... We must reexamine all of localism’s assumptions and place the environmental and social justice movements on a stronger theoretical foundation if we are to mount a serious, viable defense of the planet. No Local begins with a brief history of capitalism and a cogent explanation of its inner workings, centered on Marx’s labor theory of value. Localism seeks a return to a preindustrial economic model that romanticizes small-scale production. But simplicity and smaller scale will not get rid of the social relations that underlay capitalism. Equal exchange and bartering ...

67

Small Scale Solar PV Overview and Curriculum  

Science.gov (United States)

The Advanced Technology Environmental and Energy Center (ATEEC) provides this presentation and model curriculum for high school and community college energy technology instructors. The material focuses on the career path for small scale solar PV technicians. It includes information on career outlook, occupational competencies, sample syllabi and curriculum, high school applications and a sample lesson. The document may be downloaded in PDF file format. Users must download this resource for viewing, which requires a free log-in. There is no cost to download the item.

2012-10-03

68

Small scale cogeneration systems in Macedonia  

International Nuclear Information System (INIS)

Is it possible so-called 'small energy' to affect significantly to the State Energy Balance? It is shown that the use of small-scale cogeneration systems, and only in the industrial companies, can ensure considerable decentralized source of electricity. With the heating capacity of over 1700 MW, it is possible to establish production capacity of more than electrical power. There are analyzed the possibilities and advantages of the small cogeneration systems, as well as the necessity of preparing the feasibility studies and main designs for direct realization. (Author)

69

Small-scale universality in fluid turbulence.  

Science.gov (United States)

Turbulent flows in nature and technology possess a range of scales. The largest scales carry the memory of the physical system in which a flow is embedded. One challenge is to unravel the universal statistical properties that all turbulent flows share despite their different large-scale driving mechanisms or their particular flow geometries. In the present work, we study three turbulent flows of systematically increasing complexity. These are homogeneous and isotropic turbulence in a periodic box, turbulent shear flow between two parallel walls, and thermal convection in a closed cylindrical container. They are computed by highly resolved direct numerical simulations of the governing dynamical equations. We use these simulation data to establish two fundamental results: (i) at Reynolds numbers Re ? 10(2) the fluctuations of the velocity derivatives pass through a transition from nearly Gaussian (or slightly sub-Gaussian) to intermittent behavior that is characteristic of fully developed high Reynolds number turbulence, and (ii) beyond the transition point, the statistics of the rate of energy dissipation in all three flows obey the same Reynolds number power laws derived for homogeneous turbulence. These results allow us to claim universality of small scales even at low Reynolds numbers. Our results shed new light on the notion of when the turbulence is fully developed at the small scales without relying on the existence of an extended inertial range. PMID:25024175

Schumacher, Jörg; Scheel, Janet D; Krasnov, Dmitry; Donzis, Diego A; Yakhot, Victor; Sreenivasan, Katepalli R

2014-07-29

70

Profitability of small-scale power plants  

International Nuclear Information System (INIS)

Several small-scale power plants have been constructed in Finland during the last few years. Fuel oil and natural gas has been used as a fuel in diesel plants, natural gas in gas-turbine plants, and peat and industrial waste wood in solid fuel fired plants. Larger towns have already acquired combined power and heat generation either in their own power plants or in cooperation with industry. A usual mean of cooperation has been buying of district heat from industrial back-pressure power plants. Numerous small district heat loads still rely on separate heat production. The cheap price of electric power, caused by the good water and nuclear power conditions and long-term delivery contracts, has rendered the construction of small-scale power plants. The fuel prices have been stable for the last few years. The most significant changes have been caused by changing of exchange rate of the Finnish mark and the fuel taxation. Two power plant are reviewed in detail: 6/17 MW peat fired steam power plant and 6/6 MW oil fueled diesel power plant. The electricity prices of these two have been compared with coal condensing power and the electricity tariffs. The price comparisons have been made using the present price level. Energia-Ekono has compiled a new simulation program ELMO, operating in PC-WINDOWS environment, for simulation of cogeneration

71

Adopting small-scale production of electricity  

Energy Technology Data Exchange (ETDEWEB)

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

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

2009-07-01

72

farmer survey  

This report contains the findings of a telephone survey conducted amongst ... \\going beyond existing regulatory requirements for agricultural management ... \\Farmers' perceptions of the relevance of the ECSFDI and their satisfaction with.

73

Cold dark matter: controversies on small scales  

CERN Document Server

The cold dark matter (CDM) cosmological model has been remarkably successful in explaining cosmic structure over an enormous span of redshift, but it has faced persistent challenges from observations that probe the innermost regions of dark matter halos and the properties of the Milky Way's dwarf galaxy satellites. We review the current observational and theoretical status of these "small scale controversies." Cosmological simulations that incorporate only gravity and collisionless CDM predict halos with abundant substructure and central densities that are too high to match constraints from galaxy dynamics. The solution could lie in baryonic physics: recent numerical simulations and analytic models suggest that gravitational potential fluctuations tied to efficient supernova feedback can flatten the central cusps of halos in massive galaxies, and a combination of feedback and low star-formation efficiency could explain why most of the dark matter subhalos orbiting the Milky Way do not host visible galaxies. H...

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

2013-01-01

74

Small-Scale Features in Pulsating Aurora  

Science.gov (United States)

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.

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

2011-01-01

75

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)

76

Small Scale Foundries in Ghana: The challenges  

Directory of Open Access Journals (Sweden)

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

Emmanuel GIKUNOO

2011-12-01

77

Methods of biodiesel production for small scale  

Energy Technology Data Exchange (ETDEWEB)

The global production arrangement of biodiesel provides employments and profits. It might promote the country people social inclusion, moreover using castor plant and familiar agriculture. This culture demands use of an intensive labor and a good potential of value aggregation in their products. In front of the Biodiesel potentialities in each region, the decentralized production model shows up as an important alternative. The Brazilian biodiesel production in small scale is not well established and there are some critic aspects that could make it inviable. Among these, we can mention: low operationality, energetic inefficiency and small potentially of sub products utilities. However, this research shows an availability study of castor biodiesel production with agriculture familiar participation and aggregate value to sub products of productive process. This project minimizes investments and also the costs of operation, achieve, in this way, the economic availability of decentralized production model of biodiesel. Beyond that, the final objective of project is the execution of two models plants of biodiesel production and their utilization to labor capacity and models to others future initiative. The plant will integrate transesterification with biodigestion. The anaerobic process could be tried in each steps of the biodiesel production by technically and economically evaluation. (orig.)

Franca Belo, L. de; Viana Canabrava, D.; Serpa da Cruz, R.; Aevivanio Lins Miranda, A.; Sa Parente, E.J. Jr. de; Nascimento, R.A. (Tecbio - Tecnologias Bioenergeticas (Brazil))

2007-07-01

78

Galaxy alignment on large and small scales  

CERN Document Server

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...

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

2014-01-01

79

Small scale structure and high redshift HI  

CERN Document Server

Cosmological simulations with gas dynamics suggest that the Lyman-alpha forest is produced mainly by "small scale structure" --- filaments and sheets that are the high redshift analog of today's galaxy superclusters. There is no sharp distinction between Lyman-alpha clouds and "Gunn-Peterson" absorption produced by the fluctuating IGM -- the Lyman-alpha forest {\\it is} the Gunn-Peterson effect. Lyman limit and damped Lyman-alpha absorption arises in the radiatively cooled gas of forming galaxies. At z~2-3, most of the gas is in the photoionized, diffuse medium associated with the Lyman-alpha forest, but most of the {\\it neutral} gas is in damped Lyman-alpha systems. We discuss generic evolution of cosmic gas in a hierarchical scenario of structure formation, with particular attention to the prospects for detecting 21cm emission from high redshift HI. A scaling argument based on the present-day cluster mass function suggests that objects with M_{HI} >~ 5e11 h^{-1} \\msun should be extremely rare at z~3, so dete...

Weinberg, D H; Katz, N; Miralda-Escudé, J; Weinberg, David H; Hernquist, Lars; Katz, Neal; Miralda-Escude, Jordi

1995-01-01

80

Hoopa Valley Small Scale Hydroelectric Feasibility Project  

Energy Technology Data Exchange (ETDEWEB)

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

Curtis Miller

2009-03-22

 
 
 
 
81

Small scale combined woodgas power plant  

International Nuclear Information System (INIS)

As a first attempt to introduce biomass gasification technology in Latvia at the Faculty of Engineering of Latvia University of Agriculture an integral small scale combined heat and power (CHP) system based on a used Russian-made diesel-alternator set with electrical output 100 kWe was developed. The diesel is converted to dual fuel gas engine, using producer gas as the main fuel and gas oil as pilot fuel. To get sufficiently clean (tar content ? 250 mg/m3) woodgas for using in IC engine a downdraft type of gasifier was chosen designed and constructed on the IMBERT gasifier principles. The test runs of the first experimental model showed that the engine does not develop expected power because of high resistance of gasifier and gas cleaning system does not work sufficiently enough. There was rather high level of tar content in woodgas because the temperature in the reduction zone was low. Calculations were carried out and new technological scheme of gasification system was worked out, introducing innovative ideas aimed on improving the working parameters (author)

82

Small-scale clad-effects study  

International Nuclear Information System (INIS)

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

83

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.

84

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

85

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Lilleør, Helene Bie; Larsen, Anna Folke

2013-01-01

86

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

This study carried out to determine the efficiency of recourses used in white shrimp (Pe-naeus Vannamei) production in Lamongan Regency, East Java Province, Indonesia. The simple random sampling technique used to select 125 small-scale white shrimp farmers from six-study areas in Lamongan Regency. 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 relation...

2012-01-01

87

The assessment of some factors influencing the survival of kids in a small- scale communal goat production system  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The aim of this study was to investigate the factors affecting the survivability of goat kids to weaning, in a small-scale communal grazing system. Goat kids are the most vulnerable component of communal goat flocks and increasing their survival could increase productivity. Some of the main factors which contributed towards kid survivability were evaluated and ranked and cost benefit analysis was done. Initially 20 farmers in Jericho District, North West Province, were subjected to ...

Sebei, Phokgedi Julius

2005-01-01

88

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

Majory Ongie Meliko; Oni, Stephen A.

2011-01-01

89

Tailor-made solutions : Small-scale biofuels and trade  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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.

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

2010-01-01

90

Integrated Approach for Improving Small Scale Market Oriented Dairy Systems in Pakistan: Economic Impact of Interventions  

Directory of Open Access Journals (Sweden)

Full Text Available The International Atomic Energy Agency (IAEA launched a Coordinated Research Program in 10 developing countries including Pakistan involving small scale market oriented dairy farmers to identify and prioritize the constraints and opportunities in the selected dairy farms, develop intervention strategies and assess the economic impact of the intervention. The interventions in animal health (control of mastitis at sub-clinical stage and reduction in calf mortality, nutrition (balanced feed reproduction (mineral supplementation, and general management (training of farmers were identified and implemented in a participatory approach at the selected dairy farms. The calf mortality was reduced from 35 to 13 percent up to the age of 3 months. Use of Alfa Deval post milking teat dips reduced the incidence of sub-clinical mastitis from 34 to 5% showing economical benefits of the interventions. Partial budget technique was used to analyze its impact in the registered herds. The farmers recorded monthly quantities of different feed ingredients and seasonal green fodder offered to the animals. From this data set total metabolizeable energy requirements and availability from feed were computed which revealed that animals were deficient in metabolizeable energy in all locations. This was also confirmed by seasonal variation in body condition scoring. At some selected farms the mineral mixture supplement was introduced which exhibited increased milk yield by 5 % in addition to shorten service period by 30 days. Three sessions of training were arranged to train the farmers to care new born calves, daily farm management and detect the animals in heat efficiently to enhance the over all income of the farmers. The overall income of the farm was increased by 40%.

A. Ghaffar

2010-02-01

91

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

92

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

Science.gov (United States)

Indigenous pigs in South Africa are a source of food and economic autonomy for people in rural small-scale farming systems. The objective of the study was to assess the potential of indigenous pigs for improving communal farmer's livelihoods and to inform policy-makers about the conservation of indigenous pigs. Data were collected from 186 small-scale subsistence-oriented households and 102 small-scale market-oriented households using interviews and direct observations. Ninety-three percent of subsistence-oriented and 82 % of market-oriented households kept indigenous pigs such as Windsnyer, Kolbroek and non-descript crosses with exotic pigs mainly for selling, consumption and investment. Farmers in both production systems named diseases and parasites, followed by feed shortages, inbreeding and abortions as major constraints for pig production. Diseases and parasites were more likely to be a constraint to pig production in subsistence-oriented systems, for households where the head was not staying at home and for older farmers. Market-oriented farmers ranked productive traits such as fast growth rate, good meat quality and decent litter size as most important selection criteria for pig breeding stock, while subsistence-oriented farmers ranked good meat quality first, followed by decent growth rate and by low feed costs. We conclude that there is high potential for using indigenous pigs in subsistence-oriented production systems and for crossbreeding of indigenous pigs with imported breeds in market-oriented systems. PMID:22639035

Madzimure, James; Chimonyo, Michael; Zander, Kerstin K; Dzama, Kennedy

2012-12-01

93

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.

94

Small-scale eruptive filaments on the quiet sun  

International Nuclear Information System (INIS)

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

95

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

Directory of Open Access Journals (Sweden)

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

Erica Ell

2012-04-01

96

Development of small-scale peat production; Pienturvetuotannon kehittaeminen  

Energy Technology Data Exchange (ETDEWEB)

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

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

1997-12-01

97

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: Descrever as concepções de agricultores ecológicos sobre alimentação saudável. MÉTODOS: Estudo com abordagem qualitativa. Entre janeiro e fevereiro de 2007, foram realizadas entrevistas em profundidade com o apoio de um roteiro com 11 mulheres e um homem residentes em comunidade agrícola 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

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

98

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Public Health | Language: Portuguese Abstract in portuguese OBJETIVO: Descrever as concepções de agricultores ecológicos sobre alimentação saudável. MÉTODOS: Estudo com abordagem qualitativa. Entre janeiro e fevereiro de 2007, foram realizadas entrevistas em profundidade com o apoio de um roteiro com 11 mulheres e um homem residentes em comunidade agrícola 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 disce

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

99

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

Science.gov (United States)

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

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

2013-04-01

100

A Survey of Early Chick Mortality on Small-Scale Poultry Farms in Jos, Central Nigeria  

Directory of Open Access Journals (Sweden)

Full Text Available A questionnaire-based survey was conducted to investigate early chick mortality and its causes during the first two weeks on small-scale poultry farms in Jos, central Nigeria. The survey covered layer and broiler farms procuring day-old chicks from three selected hatcheries. Flock sizes varied from 20 birds up to 2000. Average mortality was 10.4 per flock with a standard deviation of 14.4. As a percentage of flock size, mortality was 11.4% with a standard deviation of 18.8%. The major causes of mortality were stress, Pullorum disease and diarrhoea. There was no significant relationship (p = 0.01, R2 = 0.02 between flock size and mortality. There was also no significant relationship (p = 0.01, R2 = 0.04 between mortality and the breed of stock. Of farms experiencing mortalities, only 28.8% consulted a veterinarian for diagnosis and treatment. The other 71% self-diagnosed the problems and instituted treatment which included vitamin supplementation or antimicrobial therapy, with enrofloxacin and gentamycin being the most popular drugs. Medication without consultation with qualified veterinarians may result in the abuse and misuse of antibiotics with the attendant consequences of resistance and the occurrence of drug residues in poultry and poultry products. The wide-spread use of antibiotics in the study area is cause for concern from both a veterinary and public health point of view. Although factors responsible for early chick mortality are complex, information on chick mortality on small-scale farms can be used for the training of farmers on its control. A better understanding of the causes of mortality in the crucial first few weeks of the chick’s life may lead farmers to rely more on better management such as better hygiene and sanitation and less on antibiotics for problems encountered during the early brooding period.

A.G. Ambali

2010-01-01

 
 
 
 
101

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

Directory of Open Access Journals (Sweden)

Full Text Available Agricultural productions in developing countries have largely been on subsistence basis. The farmers only produce for their families and quantity of food produced are grossly inadequate for the growing population. There is increase widespread in the level of poverty amongst the people, most especially those living in the rural areas. Small scale farming has become one of the ways to tackle the problem of lack and poverty amongst these people. The paper therefore, examines how Small Scale farming assists in alleviating poverty in both rural and urban cities; most especially through marketing of agricultural products to the people. Relevant data were sought from the 356 respondents selected for the study through the Key Informant Interviews (KII. The Student T test and Chi square statistical techniques were further employed to test the Hypotheses stated in the study. Result of the finding reveals the importance of Small Scale Farming and Agricultural Products Marketing in poverty alleviation, most especially among the rural dwellers. It also indicated lack of access to fund as the major problem facing Small Scale Farming and increase cost of transportation as the major problem facing marketing of agricultural products. The Paper recommends that Individuals and Government can combat some of these challenges facing Small Scale Farming by providing adequate basic social infrastructures; make available more funds to the farmers and create more employment opportunities amongst others. The paper concludes that Agriculture no doubt, is an important sector that needs to be given attention in any developing economy.
Key words: Small scale farming; Marketing; Rural dwellers; Key interview guide; Agricultural products and poverty

Résumé: Les productions agricoles dans les pays en voie de développement étaient principalement sur la base de subsistance. Les agriculteurs ne produisent que pour leurs familles et la quantité des aliments produits est nettement insuffisante pour la population croissante. Il y a une augmentation généralisée de la pauvreté parmi la population, plus particulièrement ceux vivant dans les zones rurales. L'agriculture à petite échelle est devenue l'une des façons pour s'attaquer au problème du manque et de la pauvreté parmi cette population. L'article examine donc comment l'agriculture à petite échelle aide à soulager le problème de la pauvreté dans les villes rurales et urbaines; plus particulièrement à travers la commercialisation des produits agricoles. Des données pertinentes ont été recueillies auprès des 356 répondants sélectionnés pour l'étude en utilisant la méthode des interviews d'informateurs clés (IIC. Le test T et les techniques statistiques de Chi carré ont été employés plus tard pour tester les hypothèses énoncées dans l'étude. Le résultat de la recherche révèle l'importance de l'agriculture à petite échelle et la commercialisation des produits agricoles dans la réduction de la pauvreté, surtout parmi les habitants des zones rurales. Il a également indiqué le manque d'accès aux fonds comme le problème majeur auquel l'agriculture à petite échelle fait face et les coûts de transport croissant comme le problème majeur de commercialisation des produits agricoles. Le document recommande que les individus et le gouvernement peuvent combattre certains de ces défis confrontés par l'agriculture à petite échelle, en assurant des adéquates infrastructures sociales de base; mettant plus de fonds à la disposition des agriculteurs et créant davantage d'emplois entre autres. L'article conclut que l'agriculture est sans aucun doute un secteur important qui doit être accordé plus d'attention dans n'importe quelle économie en développement.
Mots-clés: Petite agriculture à petite échelle; Commercialisation; Habitants ruraux; Guide d'interview clés; Produits agricoles et pauvreté

J. A. Bamiduro

2011-07-01

102

Jet Collimation by Small-Scale Magnetic Fields  

Science.gov (United States)

A popular model for jet collimation is associated with the presence of a large-scale and predominantly toroidal magnetic field originating from the central engine (a star, a black hole, or an accretion disk). Besides the problem of how such a large-scale magnetic field is generated, in this model the jet suffers from the fatal long-wave mode kink magnetohydrodynamic instability. In this paper we explore an alternative model: jet collimation by small-scale magnetic fields. These magnetic fields are assumed to be local, chaotic, and tangled, but are dominated by toroidal components. Just as in the case of a large-scale toroidal magnetic field, we show that the ``hoop stress'' of the tangled toroidal magnetic fields exerts an inward force which confines and collimates the jet. The magnetic ``hoop stress'' is balanced either by the gas pressure of the jet or by centrifugal force if the jet is spinning. Since the length scale of the magnetic field is small (wave mode kink instability. Many other problems associated with the large-scale magnetic field are also eliminated or alleviated for small-scale magnetic fields. Though it remains an open question how to generate and maintain the required small-scale magnetic fields in a jet, the scenario of jet collimation by small-scale magnetic fields is favored by the current study on disk dynamo which indicates that small-scale magnetic fields are much easier to generate than large-scale magnetic fields.

Li, Li-Xin

2002-01-01

103

Evaluation of Small-Scale Laterally Loaded Monopiles in Sand  

DEFF Research Database (Denmark)

In current designs of offshore wind turbines, monopiles are often used as foundation. The behaviour of the monopoles when subjected to lateral loading has not been fully investigated. In this paper the diameter effect on laterally loaded non-slender piles in sand is evaluated by means of results from six small-scale laboratory tests, numerical modelling of the same test setup and existing theory. From the numerical models, p?y curves are derived and compared to current design regulations. The recommendations in API (1993) and DNV (1992) are observed to be in poor agreement with the numerically obtained p?y curves. The initial stiffness, Epy*, of the p?y curves is found to increase with increasing pile diameter. Considerable uncertainties are observed to be related to small-scale testing, and the evaluations clearly indicate that the accuracy of small-scale testing is increased when increasing the pile diameter and applying overburden pressure.

Roesen, Hanne Ravn; Thomassen, Kristina

2011-01-01

104

Small-Scale Dynamo Action in Primordial Halos  

CERN Document Server

The first galaxies form due to gravitational collapse of primordial halos. During this collapse, weak magnetic seed fields get amplified exponentially by the small-scale dynamo - a process converting kinetic energy from turbulence into magnetic energy. We use the Kazantsev theory, which describes the small-scale dynamo analytically, to study magnetic field amplification for different turbulent velocity correlation functions. For incompressible turbulence (Kolmogorov turbulence), we find that the growth rate is proportional to the square root of the hydrodynamic Reynolds number, Re^(1/2). In the case of highly compressible turbulence (Burgers turbulence) the growth rate increases proportional to Re^(1/3). With a detailed chemical network we are able to follow the chemical evolution and determine the kinetic and magnetic viscosities (due to Ohmic and ambipolar diffusion) during the collapse of the halo. This way, we can calculate the growth rate of the small-scale dynamo quantitatively and predict the evolution...

Schober, Jennifer; Klessen, Ralf S; Federrath, Christoph; Bovino, Stefano; Glover, Simon; Banerjee, Robi

2012-01-01

105

Small scale wood combustion in Germany. Recent research and trends  

Energy Technology Data Exchange (ETDEWEB)

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

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

1998-12-31

106

Kinks and small-scale structure on cosmic strings  

CERN Document Server

We discuss some hitherto puzzling features of the small-scale structure of cosmic strings. We argue that kinks play a key role, and that an important quantity to study is their sharpness distribution. In particular we suggest that for very small scales the two-point correlation function of the string tangent vector varies linearly with the separation and not as a fractional power, as proposed by Polchinski and Rocha [Phys. Rev. D 74, 083504 (2006)]. However, our results are consistent with theirs, because the range of scales to which this linearity applies shrinks as evolution proceeds.

Copeland, E J

2009-01-01

107

The outlook for small-scale CHP in the USA  

Energy Technology Data Exchange (ETDEWEB)

The outlook for small-scale combined heat and power (CHP) in the USA is discussed. Improved technologies and environmental benefits suggest that the market will increase, but regulatory and other barriers are expected to limit applications in the short-term to niche markets. The environmental benefits of small-scale CHP, the market opportunities offered by the deregulation of electric power, environmental regulatory barriers, comparisons of nitrogen oxide emissions, promising emerging technologies (gas microturbines and fuel cells), emerging markets (small manufacturing plants and medium and small commercial/institutional CHP systems) and the need for policies to overcome barriers and spur future growth are considered.

Kaarsberg, T. [Northeast-Midwest Institute (United States); Bluestein, J. [Energy and Environmental Analysis Inc. (United States); Romm, J.; Rosenfeld, A. [Department of Energy (United States)

1998-06-01

108

The outlook for small-scale CHP in the USA  

International Nuclear Information System (INIS)

The outlook for small-scale combined heat and power (CHP) in the USA is discussed. Improved technologies and environmental benefits suggest that the market will increase, but regulatory and other barriers are expected to limit applications in the short-term to niche markets. The environmental benefits of small-scale CHP, the market opportunities offered by the deregulation of electric power, environmental regulatory barriers, comparisons of nitrogen oxide emissions, promising emerging technologies (gas microturbines and fuel cells), emerging markets (small manufacturing plants and medium and small commercial/institutional CHP systems) and the need for policies to overcome barriers and spur future growth are considered

109

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

Scientific Electronic Library Online (English)

Full Text Available SciELO South Africa | Language: English Abstract in english 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.

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

110

Irrigation Water Management in Small Scale Irrigation Schemes: the Case of the Ethiopian Rift Valley Lake Basin  

Directory of Open Access Journals (Sweden)

Full Text Available Appraisals of irrigation water management scenarios are crucial in project performance monitoring. A comprehensive irrigation water management study has been conducted on four small scale irrigation schemes in the Ethiopian rift valley lake basin. It is observed that from 147 irrigators 68% faced irrigation water supply unreliability, 79.1% encountered unfair distribution of water and 66 % underwent through timeliness problem in water distribution occasionally. All the investigated schemes witnessed a weak (50 % of all scheme users noted poor organization of irrigation scheme administration. The Water Users Associations (WUAs lack clear laws/by-laws and strategies to lead small or major canal operations and maintenances. Without a strong WUA it is impossible to think of filling farmer’s skill gap, to have a working maintenance strategy, fair distribution of irrigation water, reliable irrigation water supply and timely delivery of irrigation water. DOI: http://dx.doi.org/10.5755/j01.erem.67.1.6240

Mihret D. Ulsido

2014-03-01

111

Irrigation Water Management in Small Scale Irrigation Schemes: the Case of the Ethiopian Rift Valley Lake Basin  

Directory of Open Access Journals (Sweden)

Full Text Available Appraisals of irrigation water management scenarios are crucial in project performance monitoring. A comprehensive irrigation water management study has been conducted on four small scale irrigation schemes in the Ethiopian rift valley lake basin. It is observed that from 147 irrigators 68% faced irrigation water supply unreliability, 79.1% encountered unfair distribution of water and 66 % underwent through timeliness problem in water distribution occasionally. All the investigated schemes witnessed a weak (50 % of all scheme users noted poor organization of irrigation scheme administration. The Water Users Associations (WUAs lack clear laws/by-laws and strategies to lead small or major canal operations and maintenances. Without a strong WUA it is impossible to think of filling farmer’s skill gap, to have a working maintenance strategy, fair distribution of irrigation water, reliable irrigation water supply and timely delivery of irrigation water.

Mihret Dananto Ulsido

2014-04-01

112

Abelian Higgs Cosmic Strings: Small Scale Structure and Loops  

CERN Document Server

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...

Hindmarsh, Mark; Bevis, Neil

2008-01-01

113

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

114

On a spectrum of small-scale solar magnetic structures  

International Nuclear Information System (INIS)

A small-scale spectrum of solar magnetic structures is investigated. Data on average parameters and on number of solar local magnetic structures (LMS) such as active regions. ephemeral ones, magnetic nodes and magnetic elements do not contradict the representation that all LMS set is described in rough approximation by a single-like spectrum

115

Small-Scale Chp Potential in Latvia and Estonia  

Science.gov (United States)

In the research the small-scale CHP potential of Latvia and Estonia has been defined. Factors, which influence the CHP development, were analyzed in this paper, including political, geographic, climatological, legislative and technological factors. For the small-scale CHP potential assessment the three alternatives were chosen. The first alternative is the case, when only the hot water is taken into account. In this case the CHP can work with full load during the whole year because the heat load will not change (k=0,13). For the second alternative the results of the previous research were used. In this case an optimal relative heat load has been found for a small-scale CHP. This optimum value is 0,3. According to this optimum value the CHP can produce more electricity working with full load than in the first case. However, the CHP does not work whole year round. The third alternative shows the situation for the small-scale CHP when a half of the maximum heat load will be covered by the CHP. The formulas and the results for each case were provided.

Volkova, A.; Latõšv, E.; Siirde, A.

2009-01-01

116

Small-Scale Retailers in an Island Town  

Directory of Open Access Journals (Sweden)

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

Sivapalan Selvadurai

2013-10-01

117

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....

118

2010 Thin Film & Small Scale Mechanical Behavior Gordon Research Conference  

Energy Technology Data Exchange (ETDEWEB)

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.

Dr. Thomas Balk

2010-07-30

119

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

Directory of Open Access Journals (Sweden)

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

Genesis Tambang Yengoh

2010-08-01

120

Farmers Insures Success  

Science.gov (United States)

Farmers Insurance claims the No. 2 spot on the Training Top 125 with a forward-thinking training strategy linked to its primary mission: FarmersFuture 2020. It's not surprising an insurance company would have an insurance policy for the future. But Farmers takes that strategy one step further, setting its sights on 2020 with a far-reaching plan to…

Freifeld, Lorri

2012-01-01

 
 
 
 
121

Small-scale structure on cosmic strings and galaxy formation  

International Nuclear Information System (INIS)

The density perturbations produced by cosmic strings in cold dark matter are examined using the Zel'dovich approximation. We use the results from recent numerical simulations which show that the strings have significant small-scale structure. It is shown that the string network produces wakelike overdensities which may be able to account for the observed large-scale structure of the Universe. In the process of producing wakes the strings also produce large-scale peculiar velocity fields. It is shown that these velocities are coherent over distances which are too small to account for the observed large-scale streaming motions. It is also shown that the small-scale structure on the strings can fragment the wakes into pieces which have the mass of a galaxy

122

LLNL Small-Scale Friction sensitivity (BAM) Test  

Energy Technology Data Exchange (ETDEWEB)

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.

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

1996-06-01

123

Large- and small-scale dynamics of the polar cusp  

International Nuclear Information System (INIS)

Two cases of a midday cusp auroral dynamics are studied in relation to changes in the solar wind. Attention is focused on the small-scale dynamics of individual auroral forms in the midday cusp as well as more large-scale behavior of the oval in the magnetic midday sector. One case illustrates the response of the optical aurora and the geomagnetic field in the cusp when a compression in the solar wind impinges on the earth's magnetosphere. The effect of the IMF B(Y) component on the geomagnetic signature at different stations close to the cusp aurora is shown. The response of the midday port of the oval to distinct southward and northward turnings of the magnetosheath magnetic field is described, and certain small-scale auroral dynamics are discussed as possible effects of impulsive plasma transport across the dayside magnetosphere. 37 references

124

Superweakly interacting massive particle solutions to small scale structure problems.  

Science.gov (United States)

Collisionless, cold dark matter in the form of weakly interacting massive particles (WIMPs) is well motivated in particle physics, naturally yields the observed relic density, and successfully explains structure formation on large scales. On small scales, however, it predicts too much power, leading to cuspy halos, dense cores, and large numbers of subhalos, in apparent conflict with observations. We consider super-WIMP dark matter, produced with large velocity in late decays at times 10(5) - 10(8) s. As analyzed by Kaplinghat in a more general setting, we find that super-WIMPs have sufficiently large free-streaming lengths and low phase space densities to help resolve small scale structure problems while preserving all of the above-mentioned WIMP virtues. PMID:16383891

Cembranos, Jose A R; Feng, Jonathan L; Rajaraman, Arvind; Takayama, Fumihiro

2005-10-28

125

The residual anisotropy at small scales in high shear turbulence  

Science.gov (United States)

It has always been believed that turbulence in fluids can achieve a universal state at small scales with fluctuations that, becoming statistically isotropic, are characterized by universal scaling laws. In fact, in different branches of physics it is common to find conditions such that statistical isotropy is never recovered and the anisotropy induced by large scale shear contaminates the entire range of scales up to velocity gradients. We address this issue here, of particular significance, for wall bounded flows. The systematic decomposition in spherical harmonics of the correlation functions of velocity fluctuations enables us to extract the different anisotropic contributions. They vanish at small scale at a relatively fast rate under weak shear. Under strong shear instead they keep a significant amplitude up to viscous scales, thus leaving a persistent signature on the gradients which can be detected even in the statistics of low order, e.g., in the energy dissipation tensor.

Casciola, C. M.; Gualtieri, P.; Jacob, B.; Piva, R.

2007-10-01

126

Solar Receiver Design and Verification for Small Scale Polygeneration Unit  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Against a backdrop of our world’s changing climate solar thermal power generation shows great potential to move global energy production away from fossil fuels to non-polluting sources. The Department of Energy Technology at the Royal Institute of Technology Stockholm is contributing to the development and research of solar thermal power by building a solar driven small scale polygeneration unit based on an externally fired micro gas turbine. This project focused on the design, analysis and...

Aichmayer, Lukas

2011-01-01

127

Small-Scale Retailers in an Island Town  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

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

128

A parking assistance system for small-scale boats  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, the problem of designing a boat parking assistance system for a small-scale vessel is addressed. A control-oriented model is derived from the physics underlying the system, and gray-box identification is carried out by designing suitable experiments. A 3-DOF cascade control scheme is then implemented to achieve semiautomatic parking and stationkeeping. The latter mode is also shown to represent a solid groundwork for future research on fully automatic maneuvering in a harbor. T...

Formentin, Simone; Berretta, Daniele; Urbano, Nazario; Boniolo, Ivo Emanuele Francesco; Filippi, Pierpaolo; Savaresi, Sergio Matteo

2013-01-01

129

Small Scale Solar ORC system for distributed power  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

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

2009-01-01

130

On the Dynamics of Small-Scale Solar Magnetic Elements  

Science.gov (United States)

We report on the dynamics of the small-scale solar magnetic field, based on analysis of very high resolution images of the solar photosphere obtained at the Swedish Vacuum Solar Telescope. The data sets are movies from 1 to 4 hr in length, taken in several wavelength bands with a typical time between frames of 20 5. The primary method of tracking small-scale magnetic elements is with very high contrast images of photospheric bright points, taken through a 12 Å bandpass filter centered at 4305 Å in the Fraunhofer "G band." Previous studies have established that such bright points are unambiguously associated with sites of small-scale magnetic flux in the photosphere, although the details of the mechanism responsible for the brightening of the flux elements remain uncertain. The G band bright points move in the intergranular lanes at speeds from 0.5 to 5 km s-1. The motions appear to be constrained to the intergranular lanes and are primarily driven by the evolution of the local granular convection flow field. Continual fragmentation and merging of flux is the fundamental evolutionary mode of small-scale magnetic structures in the solar photosphere. Rotation and folding of chains or groups of bright points are also observed. The timescale for magnetic flux evolution in active region plage is on the order of the correlation time of granulation (typically 6-8 minutes), but significant morphological changes can occur on timescales as short as 100 5. Smaller fragments are occasionally seen to fade beyond observable contrast. The concept of a stable, isolated subarcsecond magnetic "flux tube" in the solar photosphere is inconsistent with the observations presented here.

Berger, T. E.; Title, A. M.

1996-05-01

131

Dislocation dynamics simulations of plasticity at small scales  

Energy Technology Data Exchange (ETDEWEB)

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

Zhou, Caizhi

2010-12-15

132

The small-scale treatability study sample exemption  

International Nuclear Information System (INIS)

In 1981, the Environmental Protection Agency (EPA) issued an interim final rule that conditionally exempted ''waste samples collected solely for the purpose of monitoring or testing to determine their characteristics or composition'' from RCRA Subtitle C hazardous waste regulations. This exemption [40 CFR 261.4(d)] apples to the transportation of samples between the generator and testing laboratory, temporary storage of samples at the laboratory prior to and following testing, and storage at a laboratory for specific purposes such as an enforcement action. However, the exclusion did not include large-scale samples used in treatability studies or other testing at pilot plants or other experimental facilities. As a result of comments received by the EPA subsequent to the issuance of the interim final rule, the EPA reopened the comment period on the interim final rule on September 18, 1987, and specifically requested comments on whether or not the sample exclusion should be expanded to include waste samples used in small-scale treatability studies. Almost all responders commented favorably on such a proposal. As a result, the EPA issued a final rule (53 FR 27290, July 19, 1988) conditionally exempting waste samples used in small-scale treatability studies from full regulation under Subtitle C of RCRA. The question of whether or not to extend the exclusion to larger scale as proposed by the Hazardous Waste Treatment Council was deferred until a later date. This information Brief summarizes the requirements of the small-scale treatability exemption

133

Spatial Nonlocality of the Small-Scale Solar Dynamo  

CERN Document Server

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...

Lamb, Derek A; DeForest, Craig E

2014-01-01

134

Know Your Farmer, Know Your Food  

Science.gov (United States)

With all of the talk about the demise of the family farm, the United States Department of Agriculture (USDA) has decided to step in to create this campaign to inform citizens about their own local farmers. The basic idea behind this initiative is to "create new economic opportunities by better connecting consumers with local producers." On their homepage, visitors can check out profiles of farmers in their area and learn about how support for such individuals helps strengthen rural communities and protects natural resources. The "Promote Healthy Eating" area is quite useful, as it contains links to other sites that address community food projects and a farmers market promotion program. The "Sights and Sounds" area includes images and videos from the USDA's campaign along with farmers talking about their work.

135

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

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

2008-01-01

136

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

DEFF Research Database (Denmark)

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

Kiilholma, Jenni; Stockmarr, Anders

2010-01-01

137

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

Directory of Open Access Journals (Sweden)

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.

Ngufor L. Atanga

2013-12-01

138

Small-Scale Combined Heat and Power Plants Using Biofuels  

Energy Technology Data Exchange (ETDEWEB)

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

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

2002-11-01

139

Economic comparison between small-scale AFBC and PFBC  

Energy Technology Data Exchange (ETDEWEB)

When a utility, independent power producer, or commercial firm contemplates a new small-scale power, cogeneration, or steam plant, a choice must be made among the various available technologies. Many considerations are part of this decision, including technological, regulatory, operational, environmental, and economic criteria. Each technology has its own strengths and weaknesses. For example, relative to conventional pulverized-coal plants, atmospheric fluidized-bed combustors (AFBC) and pressurized fluidized-bed combustors (PFBC) are more efficient and are capable of burning lower-grade and waste materials, but may be less proven commercially, particularly in the case of PFBC. However, in the final analysis, perhaps the most significant influence in the choice among technologies may be economic criteria. In this case, of those technologies which are acceptable from a regulatory and environmental standpoint, which technology does the job at the least cost? To make such a cost assessment, the plant builder will naturally search for information on the relative costs of various technologies. The focus of this research paper is to compare on an economic basis small-scale (in general, less than 100 MW) AFBC and PFBC power plants. Small-scale AFBC plants are fully commercialized, and recently the more-modern PFBC technology has been successfully demonstrated by a 70 MW power plant at Brilliant, Ohio. Limited economic information on PFBC technology has been compiled into a data base (see Fuller and Scherr, 1995). The literature search for the current research effort consisted of reviewing three separate databases: (1) Compendex, (2) Department of Energy, and (3) Fuller and Scherr (1995). A different literature search strategy was used in reviewing the data for PFBC and for AFBC. The dates reviewed for the PFBC data were January 1990 to June 1996. The dates reviewed for the AFBC data were 1980 to September 1996.

Fuller, J.A. [West Virginia Univ., Morgantown, WV (United States); Boyd-Powell, T. [North Carolina Central Univ., Durham, NC (United States); Smith, D.H. [Morgantown Energy Technology Center, WV (United States)

1996-12-31

140

Sunspots: From Small-Scale Inhomogeneities Towards a Global Theory  

Science.gov (United States)

The penumbra of a sunspot is a fascinating phenomenon featuring complex velocity and magnetic fields. It challenges both our understanding of radiative magneto-convection and our means to measure and derive the actual geometry of the magnetic and velocity fields. In this contribution we attempt to summarize the present state-of-the-art from an observational and a theoretical perspective. We describe spectro-polarimetric measurements which reveal that the penumbra is inhomogeneous, changing the modulus and the direction of the velocity, and the strength and the inclination of the magnetic field with depth, i.e., along the line-of-sight, and on spatial scales below 0.5 arcsec. Yet, many details of the small-scale geometry of the fields are still unclear such that the small scale inhomogeneities await a consistent explanation. A simple model which relies on magnetic flux tubes evolving in a penumbral “background” reproduces some properties of sunspot inhomogeneities, like its filamentation, its strong (Evershed-) outflows, and its uncombed geometry, but it encounters some problems in explaining the penumbral heat transport. Another model approach, which can explain the heat transport and long bright filaments, but fails to explain the Evershed flow, relies on elongated convective cells, either field-free as in the gappy penumbra or filled with horizontal magnetic field as in Danielson’s convective rolls. Such simplified models fail to give a consistent picture of all observational aspects, and it is clear that we need a more sophisticated description of the penumbra, that must result from simulations of radiative magneto-convection in inclined magnetic fields. First results of such simulations are discussed. The understanding of the small-scales will then be the key to understand the global structure and the large-scale stability of sunspots.

Schlichenmaier, Rolf

2009-04-01

 
 
 
 
141

Small Scale Testing of Core Fast Reactor Materials  

International Nuclear Information System (INIS)

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

142

Interstellar neutral hydrogen and its small-scale structure  

International Nuclear Information System (INIS)

Topics include the 21-cm emission line and the emission spectrum of neutral hydrogen, the differences between the absorption and emission spectra, the presentation of 21-cm data, the causes of small-scale structure in the interstellar HI, clusters and regions of emission, the Orion region, the effect of dust, the presence of other atoms, 21-cm absorption experiments, nonplanar neutral hydrogen, temperature and distribution of the gas, high-resolution studies, anomalous velocity neutral hydrogen, high-velocity clouds, and others. Recent data serve as an illustration of the topics discussed. (U.S.)

143

Small Scale Industries and Economic Development: Special Reference to India  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Babar, Dr S. N.

2012-01-01

144

Working Capital Management of Small Scale Industries in Rajasthan  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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

Bashar Matarneh

2012-01-01

145

Small-scale generator opportunities in the competitive supply market  

International Nuclear Information System (INIS)

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

146

Optimal Tracking Controller Design for a Small Scale Helicopter  

CERN Document Server

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

Budiyono, Agus

2008-01-01

147

Small-scale tunnel test for blast performance  

Science.gov (United States)

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

Felts, J. E.; Lee, R. J.

2014-05-01

148

Small-Scale Testing of Laterally Loaded Monopiles in Sand  

DEFF Research Database (Denmark)

In current designs of offshore wind turbines, monopiles are often used as foundation. The behaviour of the monopoles when subjected to lateral loading has not been fully investigated. In this paper, the 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.

Thomassen, Kristina; Roesen, Hanne Ravn

2011-01-01

149

Atmospheric dispersion modelling over complex terrain at small scale  

Science.gov (United States)

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

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

2014-03-01

150

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.

151

Preliminary Scaling Estimate for Select Small Scale Mixing Demonstration Tests  

Energy Technology Data Exchange (ETDEWEB)

The Hanford Site double-shell tank (DST) system provides the staging location for waste that will be transferred to the Hanford Tank Waste Treatment and Immobilization Plant (WTP). Specific WTP acceptance criteria for waste feed delivery describe the physical and chemical characteristics of the waste that must be met before the waste is transferred from the DSTs to the WTP. One of the more challenging requirements relates to the sampling and characterization of the undissolved solids (UDS) in a waste feed DST because the waste contains solid particles that settle and their concentration and relative proportion can change during the transfer of the waste in individual batches. A key uncertainty in the waste feed delivery system is the potential variation in UDS transferred in individual batches in comparison to an initial sample used for evaluating the acceptance criteria. To address this uncertainty, a number of small-scale mixing tests have been conducted as part of Washington River Protection Solutions’ Small Scale Mixing Demonstration (SSMD) project to determine the performance of the DST mixing and sampling systems.

Wells, Beric E.; Fort, James A.; Gauglitz, Phillip A.; Rector, David R.; Schonewill, Philip P.

2013-09-12

152

Atmospheric dispersion modelling over complex terrain at small scale  

Directory of Open Access Journals (Sweden)

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

Nosek S.

2014-03-01

153

Small-scale magnetic elements in Solar Cycle 23  

CERN Document Server

With the unique database from Michelson Doppler Imager aboard the Solar and Heliospheric Observatory in an interval embodying solar cycle 23, the cyclic behavior of solar small-scale magnetic elements is studied. More than 13 million small-scale magnetic elements are selected, and the following results are unclosed. (1) The quiet regions dominated the Sun\\textsf{'}s magnetic flux for about 8 years in the 12.25 year duration of Cycle 23. They contributed (0.94 -- 1.44) $\\times 10^{23}$ Mx flux to the Sun from the solar minimum to maximum. The monthly average magnetic flux of the quiet regions is 1.12 times that of active regions in the cycle. (2) The ratio of quiet region flux to that of the total Sun equally characterizes the course of a solar cycle. The 6-month running-average flux ratio of quiet region had been larger than 90.0% for 28 continuous months from July 2007 to October 2009, which characterizes very well the grand solar minima of Cycles 23-24. (3) From the small to large end of the flux spectrum, ...

Jin, C L; Song, Q; Zhao, H

2011-01-01

154

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)

155

Small-scale engagement model with arrivals: analytical solutions  

International Nuclear Information System (INIS)

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

156

Small-scale AFBC hot air gas turbine power cycle  

Energy Technology Data Exchange (ETDEWEB)

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

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

1995-12-31

157

Small-scale AFBC hot air gas turbine power cycle  

Energy Technology Data Exchange (ETDEWEB)

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

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

1995-12-31

158

Small Scale Mechanization of Thinning in Artificial Coniferous Plantation  

Directory of Open Access Journals (Sweden)

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.

Serena Savelli

2010-06-01

159

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)

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.

L. Papa

2010-01-01

160

Small Scale Dairy Farming Practice in a Selective Area of Bangladesh  

Directory of Open Access Journals (Sweden)

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

M.M. Hossain

2005-01-01

 
 
 
 
161

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

Directory of Open Access Journals (Sweden)

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.

Juan M. Castano

2014-09-01

162

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

163

Small Scale Gasification: Gas Engine CHP for Biofuels  

Energy Technology Data Exchange (ETDEWEB)

In a joint project, Linnaeus Univ. in Vaexjoe (LNU) and the Faculty of Engineering at Lund Univ. (LTH) were commissioned by the Swedish Energy Agency to make an inventory of the techniques and systems for small scale gasifier-gas engine combined heat and power (CHP) production and to evaluate the technology. Small scale is defined here as plants up to 10 MW{sub th}, and the fuel used in the gasifier is some kind of biofuel, usually woody biofuel in the form of chips, pellets, or sawdust. The study is presented in this report. The report has been compiled by searching the literature, participating in seminars, visiting plants, interviewing contact people, and following up contacts by e-mail and phone. The first, descriptive part of the report, examines the state-of-the-art technology for gasification, gas cleaning, and gas engines. The second part presents case studies of the selected plants: - Meva Innovation's VIPP-VORTEX CHP plant - DTU's VIKING CHP plant - Guessing bio-power station - Harbooere CHP plant -Skive CHP plant The case studies examine the features of the plants and the included unit operations, the kinds of fuels used and the net electricity and overall efficiencies obtained. The investment and operating costs are presented when available as are figures on plant availability. In addition we survey the international situation, mainly covering developing countries. Generally, the technology is sufficiently mature for commercialization, though some unit operations, for example catalytic tar reforming, still needs further development. Further development and optimization will probably streamline the performance of the various plants so that their biofuel-to-electricity efficiency reaches 30-40 % and overall performance efficiency in the range of 90 %. The Harbooere, Skive, and Guessing plant types are considered appropriate for municipal CHP systems, while the Viking and VIPP-VORTEX plants are smaller and considered appropriate for replacing hot water plants in district heating network. The Danish Technical Univ. (DTU) Biomass Gasification Group and Meva International have identified a potentially large market in the developing countries of Asia. Areas for suggested further research and development include: - Gas cleaning/upgrading - Utilization of produced heat - System integration/optimization - Small scale oxygen production - Gas engine developments

Brandin, Jan (Linnaeus Univ., Vaexjoe. Faculty of Science and Engineering, School of Engineering (Sweden)); Tuner, Martin; Odenbrand, Ingemar (The Faculty of Engineering at Lund Univ. (LTH) (Sweden))

2011-07-01

164

Scaling properties of small-scale fluctuations in magnetohydrodynamic turbulence  

CERN Document Server

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...

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

2014-01-01

165

Small Scale Response and Modeling of Periodically Forced Turbulence  

Science.gov (United States)

The response of the small scales of isotropic turbulence to periodic large scale forcing is studied using two-point closures. The frequency response of the turbulent kinetic energy and dissipation rate, and the phase shifts between production, energy and dissipation are determined as functions of Reynolds number. It is observed that the amplitude and phase of the dissipation exhibit nontrivial frequency and Reynolds number dependence that reveals a filtering effect of the energy cascade. Perturbation analysis is applied to understand this behavior which is shown to depend on distant interactions between widely separated scales of motion. Finally, the extent to which finite dimensional models (standard two-equation models and various generalizations) can reproduce the observed behavior is discussed.

Bos, Wouter; Clark, Timothy T.; Rubinstein, Robert

2007-01-01

166

Sizing aspects of a small scale grid connected PV system  

Energy Technology Data Exchange (ETDEWEB)

Photovoltaics can be used in grid connected mode in two ways: as array installed at the end use site, such as on rooftops, or as utility-scale generating stations. The present paper describes a small-scale grid connected Photovoltaic system. The paper starts with the structure and characterization of the system. The principal technical parameter data are also presented. The used monitoring parameters indicate the principal meteorological data, air temperature and solar radiation data for the location sited at Agigea, at the Black Sea and the produced energy by the PV modules. The present application is made by 1 subsystem with 1200 Wp power and with the panel inclination possibility, using different type of PV modules. The paper presents a simulation model for this system realized with commercial software packages and with a one self made Matlab model that evaluates the energy balance of the PV system. All the simulation and measurements data are presented. (orig.)

Bartha, S.; Teodoreanu, D.I.; Teodoreanu, M.; Negreanu, C. [I.C.P.E.-New Energy Sources Laboratory (NESL), Bucharest (Romania); Farkas, I.; Seres, I. [Szent Istvan University, Goedoelloe (Hungary). Department of Physics and Process Control

2008-07-01

167

Small scale renewable solar energy and the best result project  

Energy Technology Data Exchange (ETDEWEB)

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

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

2008-07-01

168

Small-scale Testing of Bucket Foundations in Sand  

DEFF Research Database (Denmark)

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.

Knudsen, BjØrn S.; Østergaard, Martin Underlin

2013-01-01

169

Small Scale Industries and Economic Development: Special Reference to India  

Directory of Open Access Journals (Sweden)

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

Dr. S. N. Babar

2012-04-01

170

CMB spectral distortions from small-scale isocurvature fluctuations  

CERN Document Server

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 ...

Chluba, Jens

2013-01-01

171

Performance analysis of small-scale experimental facility of TWDEC  

International Nuclear Information System (INIS)

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

172

Modelling Relativistic Astrophysics at the Large and Small Scale  

CERN Document Server

In this thesis different numerical methods, as well as applications of the methods to a number of current problems in relativistic astrophysics, are presented. In the first part the theoretical foundation and numerical implementation of a new general relativistic magnetohydrodynamics code is discussed. A new form of the equations of motion using global coordinates, but evolving the dynamical variables from the point of view of a local observer is presented. No assumptions are made about the background metric and the design is ready to be coupled with methods solving the full Einstein equations. In the second part of the thesis important results concerning the understanding of collisionless shocks, obtained from experiments with a relativistic charged particle code, are presented. Relativistic collisionless shocks are important in a range of astrophysical objects; in particular in gamma ray burst afterglows and other relativistic jets. It is shown that a strong small scale, fluctuating, and predominantly trans...

Haugbölle, T

2005-01-01

173

Manufacture of a Biodegradable Detergent on Small Scale  

Directory of Open Access Journals (Sweden)

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.

Abdulla A. Aziz A. Majeed

2010-12-01

174

Small-scale morphology across the surf zone  

Science.gov (United States)

Small-scale (scale morphology were measured in response to changing waves and currents during the 2 weeks examined. Three cases are examined in detail: (1) mild waves and weak longshore currents resulting in wave ripples throughout the study area; (2) storm waves with strong longshore currents resulting in lunate and straight-crested mega-ripples in the trough of the barred beach; and (3) narrow-band, normally incident waves with a strong rip current resulting in a planar bed except in the throat of the rip where mega-ripples were measured. Wavenumber spectra of the bed were generally broad, indicating newly formed ripples coexisted with residual ripples from the past to form complex, multi-scaled ripple patterns.

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

1998-01-01

175

Optimal Combustion Conditions for a Small-scale Biomass Boiler  

Directory of Open Access Journals (Sweden)

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

Viktor Pla?ek

2012-01-01

176

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.

177

Small-scale systems for in vivo drug delivery.  

Science.gov (United States)

Recent developments in the application of micro- and nanosystems for drug administration include a diverse range of new materials and methods. New approaches include the on-demand activation of molecular interactions, novel diffusion-controlled delivery devices, nanostructured 'smart' surfaces and materials, and prospects for coupling drug delivery to sensors and implants. Micro- and nanotechnologies are enabling the design of novel methods such as radio-frequency addressing of individual molecules or the suppression of immune response to a release device. Current challenges include the need to balance the small scale of the devices with the quantities of drugs that are clinically necessary, the requirement for more stable sensor platforms, and the development of methods to evaluate these new materials and devices for safety and efficacy. PMID:14520404

LaVan, David A; McGuire, Terry; Langer, Robert

2003-10-01

178

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

179

Numerical simulation of small scale soft impact tests  

International Nuclear Information System (INIS)

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

180

CAMUI Type Hybrid Rocket as Small Scale Ballistic Flight Testbed  

Science.gov (United States)

The authors have been developing CAMUI (Cascaded Multistage Impinging-jet) type hybrid rockets, explosive-flee small rocket motors. This is to downsize the scale of suborbital flight experiments on space related technology development. A key idea is a new fuel grain design to increase gasification rates of a solid fuels. By the new fuel grain design, the combustion gas repeatedly impinges on fuel surfaces to hasten the heat transfer to the fuel. Suborbital flight experiments by sounding rockets provide variety of test beds to accumulate basic technologies common to the next step of space development in Japan. By using hybrid rockets one can take the cost advantage of small-scale rocket experiments. This cost advantage improves robustness of space technology development projects by dispersion of risk.

Nagata, Harunori; Uematsu, Tsutomu; Ito, Kenichi

 
 
 
 
181

Burn-rate Measurement on Small-scale Rocket Motors  

Directory of Open Access Journals (Sweden)

Full Text Available Small-scale rocket motors are widely used by propulsion industries to carry out burn rate measurement for a variety of needs. Several automated data-reduction procedures have been implemented to derive burn rate from pressure-time profiles resulting from experimentation. Even if these are easy and fast to use, these procedures are not completely reliable in that these measure only the average behaviour of a motor. A new model has recently been proposed to overcome this problem. However, it was soon noticed that the results depend on the propellant grain production and forming processes even if the motor hardware is the same. A series of propellant grains has been produced to be sampled to map the local ballistic behaviour and changes introduced by the manufacturing process. In this study, sampling and testing procedures are reported and the results of an almost complete grain mapping are discussed.

F. Maggi

2006-07-01

182

First Principle Approach to Modeling of Small Scale Helicopter  

CERN Document Server

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

Budiyono, A; Lesmana, H

2008-01-01

183

Small-scale hydrous pyrolysis of macromolecular material in meteorites  

Science.gov (United States)

The hydrous pyrolysis method, usually performed on several hundred grams of terrestrial rock sample, has been scaled down to accommodate less than two grams of meteorite sample. This technique makes full use of the high yields associated with hydrous pyrolysis experiments and permits the investigation of the meteorite macromolecular material, the major organic component in carbonaceous meteorites. The hydrous pyrolysis procedure transforms the high molecular weight macromolecular material into low molecular weight fragments. The released entities can then be extracted with supercritical fluid extraction. In contrast to the parent structure, the pyrolysis products are amenable for analysis by gas chromatography-based techniques. When subjected to hydrous pyrolysis, two carbonaceous chondrites (Orgueil and Cold Bokkeveld) released generally similar products, which consisted of abundant volatile aromatic and alkyl-substituted aromatic compounds. These results revealed the ability of small-scale hydrous pyrolysis to dissect extraterrestrial macromolecular material and thereby reveal its organic constitution.

Sephton, M. A.; Pillinger, C. T.; Gilmour, I.

1998-12-01

184

Properties of small-scale magnetism of stellar atmospheres  

Science.gov (United States)

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.

Steiner, Oskar; Salhab, René; Freytag, Bernd; Rajaguru, S. P.; Schaffenberger, Werner; Steffen, Matthias

2014-10-01

185

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

Science.gov (United States)

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

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

2011-05-01

186

Determinants of Farmers’ Agricultural Diversification: The Case of Cambodia  

Directory of Open Access Journals (Sweden)

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.

Kimty Seng

2014-08-01

187

Putting farmers first: reshaping agricultural research in West Africa  

Energy Technology Data Exchange (ETDEWEB)

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.

Pimbert, Michel

2012-01-15

188

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

Directory of Open Access Journals (Sweden)

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

Kafiriti, EM.

2003-01-01

189

Investigation of the feasibility of a small scale transmutation device  

Science.gov (United States)

This dissertation presents the design and feasibility of a small-scale, fusion-based transmutation device incorporating a commercially available neutron generator. It also presents the design features necessary to optimize the device and render it practical for the transmutation of selected long-lived fission products and actinides. Four conceptual designs of a transmutation device were used to study the transformation of seven radionuclides: long-lived fission products (Tc-99 and I-129), short-lived fission products (Cs-137 and Sr-90), and selective actinides (Am-241, Pu-238, and Pu-239). These radionuclides were chosen because they are major components of spent nuclear fuel and also because they exist as legacy sources that are being stored pending a decision regarding their ultimate disposition. The four designs include the use of two different devices; a Deuterium-Deuterium (D-D) neutron generator (for one design) and a Deuterium-Tritium (D-T) neutron generator (for three designs) in configurations which provide different neutron energy spectra for targeting the radionuclide for transmutation. Key parameters analyzed include total fluence and flux requirements; transmutation effectiveness measured as irradiation effective half-life; and activation products generated along with their characteristics: activity, dose rate, decay, and ingestion and inhalation radiotoxicity. From this investigation, conclusions were drawn about the feasibility of the device, the design and technology enhancements that would be required to make transmutation practical, the most beneficial design for each radionuclide, the consequence of the transmutation, and radiation protection issues that are important for the conceptual design of the transmutation device. Key conclusions from this investigation include: (1) the transmutation of long-lived fission products and select actinides can be practical using a small-scale, fusion driven transmutation device; (2) the transmutation of long-lived fission products could result in an irradiation effective half-life of a few years with a three order magnitude increase in the on-target neutron flux accomplishable through a combination of technological enhancements to the source and system design optimization; (3) the transmutation of long-lived fission products requires a thermal-slow energy spectrum to prevent the generation of activation products with half-lives even longer than the original radionuclide; (4) there is no benefit in trying to transmute short-lived fission products due to the ineffectiveness of the transmutation process and the generation of a multiplicity of counterproductive activation products; (5) for actinides, irradiation effective half-lives of target flux; (6) the ideal neutron energy spectra for transmuting actinides is highly dependent on the particular radionuclide and its fission-to-capture ratio as they determine the generationrate of other actinides; and (7) the methodology developed in this dissertation provides a mechanism that can be used for studying the feasibility of transmuting other radionuclides, and its application can be extended to studying the production of radionuclides of interest in a transmutation process. Although large-scale transmutation technology is presently being researched world-wide for spent fuel management applications, such technology will not be viable for a couple of decades. This dissertation investigated the concept of a small-scale transmutation device using present technology. The results of this research show that with reasonable enhancements, transmutation of specific radionuclides can be practical in the near term.

Sit, Roger Carson

190

Characteristics of Feed Mills at Farmers Group Scale in Supporting the Development of Beef Cattle  

Digital Repository Infrastructure Vision for European Research (DRIVER)

One of the strategies to increase the availability of beef cattle feed in small holder livestock farms is to build feed industry of raw material agricultural waste-based. Development of small scale feed mills at the farmers group level is a necessity in supporting their farm. The important thing to consider in feed production not only on the quality aspect, but also the economical aspects need to be considered, which can be affordable by the farmers. The farmer group of Padang Tawang is one o...

A Syamsu, Jasmal; Yusuf, Muhammad; Abdullah, Agustina

2014-01-01

191

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

Science.gov (United States)

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…

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

2014-01-01

192

Small-scale recombination He - Sr+(Ca+ ) lasers  

International Nuclear Information System (INIS)

A review of specific features and output characteristics of small-scale (l?30 cm, d?1.1cm) gas-discharge recombination He-Sr+ (?=430.5 nm) and He- Ca+ (?=373.7nm) lasers is provided. Such compact lasers are characterised by a relatively high reliability and durability. These lasers are easy to operate and are capable of generating laser pulses with high repetition rates f, a high specific mean power Psp, and an improved quality of output radiation. A typical mean power P of self-heating sealed-off He-Sr+ (Ca+) laser tubes with l? 30 cm and d? 1 cm is ? 0.5 W. The best specific characteristics of a He-Sr+ laser with tubes of this type were achieved with l=20 cm and d=0.6 cm (Psp=73 mW cm-3) and l=9 cm and d=0.55 cm (Psp=65 W cm-3). The best specific characteristics for a He-Ca+ laser were achieved with l=26.5 cm and d=0.7 cm (Psp=50 mW cm-3). The use of forced water cooling in a He-Sr+(Ca+) laser allowed the powers P=3.9 W and Psp=137 mW cm-3 to be achieved with a tube with l=30 cm and d=1.1 cm for f=29 kHz. A new method of inputting metal vapours based on cataphoresis is considered in detail. Using this method allowed the output characteristics of a He-Sr+ laser to be considerably improved and a record specific power Psp=277 mW cm-3 to be a277 mW cm-3 to be achieved for a tube with l=26 cm and d=0.3 cm with f=30 kHz and P=510 mW. A record gain, 0.15 cm-1, was also achieved under these conditions. Some possible areas of applications of small-scale He-Sr+(Ca+) lasers in semiconductor microtechnology, holography, ecology, and medicine are outlined. (invited paper)

193

Robust, small-scale cultivation platform for Streptomyces coelicolor  

DEFF Research Database (Denmark)

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

Sohoni, Sujata Vijay; Bapat, Prashant Madhusudan

2012-01-01

194

AFBC-HAGT, an efficient small scale power plant  

Energy Technology Data Exchange (ETDEWEB)

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

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

1997-12-31

195

CSF farmer handbook  

Mar 31, 2011 ... Natural England CSF Capital Grant Scheme 2010/11 Farmer Handbook (CSF 3) \\... 64 Consents for work in Designated Conservation. Areas or relating to a ... \\grant aid towards the improvement or installation of facilities that ...

196

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

Energy Technology Data Exchange (ETDEWEB)

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. (author)

Grau, Baquero; Bernat, Esteban; Antoni, Rius; Jordi-Roger, Riba; Rita, Puig [Escola Universitaria d' Igualada (EUETII-Escola d' Adoberia), Universitat Politecnica de Catalunya, Placa del Rei 15, 08700 Igualada, Catalunya (Spain)

2010-01-15

197

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.

198

Small-scale Nonlinear Dynamics of K-mouflage Theories  

CERN Document Server

We investigate the small-scale static configurations of K-mouflage models defined by a general function $K(\\chi)$ of the kinetic terms. The fifth force is screened by the nonlinear K-mouflage mechanism if $K'(\\chi)$ grows sufficiently fast for large negative $\\chi$. In the general non-spherically symmetric case, the fifth force is not aligned with the Newtonian force. For spherically symmetric static matter density profiles, the results depend on the potential function $W_{-}(y) = y K'(-y^2/2)$, which must be monotonically increasing to $+\\infty$ for $y \\geq 0$ to guarantee the existence of a single solution throughout space for any matter density profile. Starting from vanishing initial conditions or from nearby profiles, 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 ...

Brax, Philippe

2014-01-01

199

Social and Ecological Dynamics of Small-Scale Fisheries  

Science.gov (United States)

Globalization's reach is rapidly extending to touch some of the most remote communities of the world, but we have yet to understand its scale and impact. On Nicaragua's previously remote Miskitu Coast, the introduction of new markets and global demand for seafood has resulted in changes in fishermen's harvest behavior manifested within the local fishery. Small-scale fisheries are a significant component in sustaining global fish trade, ensuring food security, and alleviating poverty, but because the fishermen are disperse, numerous and located in remote areas, the social and ecological dynamics of the system are poorly understood. Previous work has indicated a decline in fish abundance as a result of connection to markets, yet fishermen's response to this decline and the resulting shift in harvest strategy requires further examination. I identify the ecological and social factors that explain changes in fishermen behavior and use an innovative application of social network analysis to understand these changes. I also use interviews with fishermen and fishery-dependent surveys to measure catch and release behavior and seasonal gear use. Results demonstrate multiple cliques within a community that mitigate the response of fishermen to changes in the fishery. This research applies techniques in social science to address challenges in sustainable management of fisheries. As fisheries managers consider implementing new regulations, such as seasonal restrictions on gear, it is essential to understand not just how this might impact fish abundance, but how and why human systems respond as they do.

Stevens, K.; Kramer, D.; Frank, K.

2012-12-01

200

Small-scale inviscid accretion discs around black holes  

CERN Document Server

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

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

2000-01-01

 
 
 
 
201

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.

202

Small-scale swirl events in the quiet Sun chromosphere  

CERN Document Server

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 ...

Wedemeyer-Böhm, Sven

2009-01-01

203

An analytical model for small-scale rural bioenergy systems  

Energy Technology Data Exchange (ETDEWEB)

The strong international growth of agrofuels in the last decade brought the interest in bioenergy back on the agenda. While rural areas are typically highly dependent on bioenergy and have at the same time the largest biomass potentials, most approaches focus on large-scale production and processing of biomass for the energy demand of urban areas. This paper presents an analytical model for rural bioenergy supply pathways, which supports a simplified and manageable small-scale bioenergy planning. To this aim, different supply pathways are quantitatively compared by their conversion and cost efficiency to analyse technological feasibility and economical viability. The focus lies on the three basic rural service categories of lighting, cooking and motive power. Additionally, a set of criteria is developed to qualitatively discuss other effects on rural livelihood. The methodology is applied to a Jatropha project on the Indonesian island Sumbawa. Results of the quantitative and qualitative analysis are combined to evaluate different energy supply pathways. The paper concludes with a discussion of the proposed methodology. (orig.)

Gaul, Mirco [Technische Univ. Berlin (Germany). Inst. for Energy Engineering and Centre for Technology and Society

2011-07-01

204

Small scale chromospheric jets above a sunspot light bridge  

CERN Document Server

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...

Louis, Rohan E; Ichimoto, Kiyoshi

2014-01-01

205

Small?scale distribution of fish in offshore windfarms  

DEFF Research Database (Denmark)

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

Hansen, Kamilla Sande; Stenberg, Claus

2012-01-01

206

Jet Collimation by Small-Scale Magnetic Fields  

CERN Document Server

A popular model for jet collimation is associated with the presence of a large-scale and predominantly toroidal magnetic field originating from the central engine (a star, a black hole, or an accretion disk). Besides the problem of how such a large-scale magnetic field is generated, in this model the jet suffers from the fatal long-wave mode kink magnetohydrodynamic instability. In this paper we explore an alternative model: jet collimation by small-scale magnetic fields. These magnetic fields are assumed to be local, chaotic, tangled, but are dominated by toroidal components. Just as in the case of a large-scale toroidal magnetic field, we show that the ``hoop stress'' of the tangled toroidal magnetic fields exerts an inward force which confines and collimates the jet. The magnetic ``hoop stress'' is balanced either by the gas pressure of the jet, or by the centrifugal force if the jet is spinning. Since the length-scale of the magnetic field is small (< the cross-sectional radius of the jet << the ...

Li, L X

2002-01-01

207

Small Scale Microwave Bursts in Long-duration Solar Flares  

CERN Document Server

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

Tan, Baolin

2013-01-01

208

Turbulence Small Scale Properties Investigated by Light Scattering  

Science.gov (United States)

The small scales properties of turbulent density fluctuations are experimentally investigated using light scattering. This technique yields the Fourier transform of the density fluctuations. The fully developed turbulent flow is a compressed air-jet issuing from a convergent nozzle. The deviation of the signal probability distribution from a Gaussian is quantified using the flatness factor that tends to 3 with decreasing scales. The k-spectrum is determined and displays a power law which deviates from the Kolmogorov prediction. The behavior of the three-dimensional spectrum in time is shown to exhibit what we qualify as a singular behavior in agreement with what could be expected from the multifractal model. The spectrum of singularities, computed to quantify this aspect, tends towards a mono-fractal spectrum with increasing wave number. The temporal correlation coefficient is shown to tend towards a white noise. These results can be interpreted as caused by a lack of eddies generation in the inertial sub-range with decreasing scales.

Ghassan Y, Antar

2001-11-01

209

Configuration scheme for small scale Multi-FPGA systems  

Directory of Open Access Journals (Sweden)

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

Chengchang Zhang

2011-08-01

210

Arbuscular mycorrhizal fungal communities are phylogenetically clustered at small scales.  

Science.gov (United States)

Next-generation sequencing technologies with markers covering the full Glomeromycota phylum were used to uncover phylogenetic community structure of arbuscular mycorrhizal fungi (AMF) associated with Festuca brevipila. The study system was a semi-arid grassland with high plant diversity and a steep environmental gradient in pH, C, N, P and soil water content. The AMF community in roots and rhizosphere soil were analyzed separately and consisted of 74 distinct operational taxonomic units (OTUs) in total. Community-level variance partitioning showed that the role of environmental factors in determining AM species composition was marginal when controlling for spatial autocorrelation at multiple scales. Instead, phylogenetic distance and spatial distance were major correlates of AMF communities: OTUs that were more closely related (and which therefore may have similar traits) were more likely to co-occur. This pattern was insensitive to phylogenetic sampling breadth. Given the minor effects of the environment, we propose that at small scales closely related AMF positively associate through biotic factors such as plant-AMF filtering and interactions within the soil biota. PMID:24824667

Horn, Sebastian; Caruso, Tancredi; Verbruggen, Erik; Rillig, Matthias C; Hempel, Stefan

2014-11-01

211

Chiral Extrapolations and the Covariant Small Scale Expansion  

CERN Document Server

We calculate the nucleon and the delta mass to fourth order in a covariant formulation of the small scale expansion. We analyze lattice data from the MILC collaboration and demonstrate that the available lattice data combined with our knowledge of the physical values for the nucleon and delta masses lead to consistent chiral extrapolation functions for both observables up to fairly large pion masses. This holds in particular for very recent data on the delta mass from the QCDSF collaboration. The resulting pion-nucleon sigma term is sigma_{piN} = 48.9 MeV. This first quantitative analysis of the quark-mass dependence of the structure of the Delta(1232) in full QCD within chiral effective field theory suggests that (the real part of) the nucleon-delta mass-splitting in the chiral limit, Delta_0 = 0.33 GeV, is slightly larger than at the physical point. Further analysis of simultaneous fits to nucleon and delta lattice data are needed for a precision determination of the properties of the first excited state of...

Bernard, V; Meißner, Ulf G; Hemmert, Thomas R.; Mei{\\ss}ner, Ulf-G.

2005-01-01

212

Hydropower harvesting from a small scale reciprocating system  

Energy Technology Data Exchange (ETDEWEB)

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

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

2011-05-15

213

Woodbased fuels in small-scale regional heating plants  

Energy Technology Data Exchange (ETDEWEB)

This biomass heating report is compiled as part of the joint Nordic countries EU-Bothnia-Atlantica funded Forest Power project and it explores wood fuels and especially the use of woodchips primarily in the small-scale regional heating plants of Central Ostrobothnia energy cooperatives. The Forest Power project's main coordinator is the Kannus Unit of the Finnish Forest Research Institute (METLA). Other partners in Finland are CENTRIA, the research and development unit of the Central Ostrobothnia University of Applied Sciences, the Kannus Unit of the Central Ostrobothnia Rural Institute, Central Ostrobothnia Forest Owners Association and, of course, the region's energy cooperatives. The ETPC unit at Umeaa University in Sweden also actively participated in this project. This report is based on field measurements conducted during the project at the Kaelviae energy cooperative's woodchip heating plant and is CENTRIA's most visible project outcome. The following individuals participated as researchers in the field measurements: Kari Manninen, project engineer, Anu-Sisko Perttunen, project officer, Martti Harkonen, principal lecturer, Lasse Jansson, director, research and development CENTRIA, Pentti Etelamaki, Central Ostrobothnia Forest Owners Association, Heikki Kykyri and Perttu Suonpera, Kaelviae energy cooperative. The following were project members: Dan Bostrom, Christoffer Boman, Jonathan Fagerstrom, Markus Brostrom and Rainer Backman of Umeaa University's ETPC unit. Martti Harkonen was responsible for the further analysis of the measurement results and report writing. (orig.)

Harkonen, M.

2012-07-01

214

Observations of How Magnetofluid Turbulence Dissipates at Small Scales  

Science.gov (United States)

The solar wind is a turbulent magneto fluid that can be studied intensively at multiple scales. Investigations using single spacecraft have revealed much about the properties of the solar wind throughout the heliosphere (from 0.3 AU to 100 AU). More recently, data from multiple spacecraft have provided further details of both the statistical properties of the turbulence and its small-scale structure. In particular, high time resolution magnetic field measurements from the four Cluster spacecrafl have led to the conclusion that at spatial scales of order the proton inertial length and smaller, the turbulence becomes strongly anisotropic and the power in fluctuations that are perpendicular to the (local) magnetic field is measured to be much larger than that in fluctuations that are parallel to the magnetic field. As the spatial scales approach the electron inertial length, the power is almost completely dissipated. Various analysis techniques and theoretical ideas have been put forward to account for the properties of those measurements. The talk will describe the current state of observations, theory and simulations.

Goldstein, M. L.; Sahraoui, Fouad

2012-01-01

215

Small scale variability in quiet sun and coronal holes  

Science.gov (United States)

IRIS (Interface Region Imaging Spectrograph) was launched in 2013 and revealed small-scale rapid brightening variations in large regions in the quiet sun and coronal holes. Their lifetime is smaller than a couple of minutes and the distance between them is of a granular scale. We are going to present a statistical study of their observed properties such as variability, lifetime, frequency using the images of the SJI, and velocities, and temperatures using the spectral data coming IRIS. The spectrograph reveals that most of this emission comes from the continuum and their properties reveals that most of these events result from acoustic shocks. We compare our observations with synthetic observables (using forward modeling with the RH and multi3D code) from recent numerical 3D radiative-MHD simulations using the Bifrost code (Gudiksen et al. 2011). Similar rapid brightening variability of chromospheric synthetic images has been also reproduced in our simulations with mainly unipolar field. We will describe their evolution, how they are driven and their thermodynamic properties from the simulations.

Martinez-Sykora, Juan; De Pontieu, Bart

216

Power spectrum for the small-scale Universe  

CERN Document Server

The first objects to form in a cold dark matter universe present a daunting challenge for models of structure formation. In the ultra small-scale limit, CDM structures form nearly simultaneously across a wide range of scales. Hierarchical clustering no longer provides a guiding principle for theoretical analyses and the computation time to carry out credible simulations becomes prohibitively high. To gain insight into this problem, we perform high-resolution (N=720^3 - 1584^3) simulations of an Einstein-de Sitter cosmology where the initial power spectrum is P(k) proportional to k^n, with -2.5 < n < -1. Self-similar scaling is established for n=-1 and n=-2 more convincingly than in previous, lower-resolution simulations and for the first time, self-similar scaling is established for an n=-2.25 simulation. However, finite box-size effects induce departures from self-similar scaling in our n=-2.5 simulation. We compare our results with the predictions for the power spectrum from (one-loop) perturbation th...

Widrow, Lawrence M; Thacker, Robert J; Richardson, Mark; Scannapieco, Evan

2009-01-01

217

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)

218

Small-scale dynamo action in rotating compressible convection  

CERN Document Server

We study dynamo action in a convective layer of electrically-conducting, compressible fluid, rotating about the vertical axis. At the upper and lower bounding surfaces, perfectly-conducting boundary conditions are adopted for the magnetic field. Two different levels of thermal stratification are considered. If the magnetic diffusivity is sufficiently small, the convection acts as a small-scale dynamo. Using a definition for the magnetic Reynolds number $R_M$ that is based upon the horizontal integral scale and the horizontally-averaged velocity at the mid-layer of the domain, we find that rotation tends to reduce the critical value of $R_M$ above which dynamo action is observed. Increasing the level of thermal stratification within the layer does not significantly alter the critical value of $R_M$ in the rotating calculations, but it does lead to a reduction in this critical value in the non-rotating cases. At the highest computationally-accessible values of the magnetic Reynolds number, the saturation levels...

Favier, Benjamin F N

2011-01-01

219

WTO and its Impact on Small Scale Industries in India  

Directory of Open Access Journals (Sweden)

Full Text Available 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 operations, expand their workplace with minimal investment and has facilitated consumers to enjoy a wide array of goods and services. WTO aims to develop the country’s economy by encouraging its export among the member countries. Further, it facilitates for availing new technologies from various countries at a lower cost. In this connection, the present paper attempts to probe peculiar issues relating to WTO, its repercussions on Indian SSIs in the globalized scenario and analyzes its growth performance with regard to units, employment, output, exports and concludes by recommending appropriate credit availability measures for ensuring their sustenance along with competitive growth.

Anchal Singh

2014-09-01

220

Scaling Properties of Small-scale Fluctuations in Magnetohydrodynamic Turbulence  

Science.gov (United States)

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 Alfvén 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 also imposes stringent conditions on numerical studies of MHD turbulence. In contrast with the hydrodynamic case, the discretization scale in numerical simulations of MHD turbulence should decrease faster than the dissipation scale, in order for the simulations to remain resolved as the Reynolds number increases.

Perez, Jean Carlos; Mason, Joanne; Boldyrev, Stanislav; Cattaneo, Fausto

2014-09-01

 
 
 
 
221

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

DEFF Research Database (Denmark)

Cotton is known as the “white gold” of Africa since it is the only export crop in which the continent’s share in the world market has increased over the past decades. Total cotton production as well as productivity grew particularly in Western and Central Africa. In contrast, cotton production grew much less in Eastern and Southern Africa and the increase in production was mainly a result of expansion of land under cultivation and the number of producers, rather than of improved productivity (e.g. Poulton et al., 2004; Delpeuch and Vandeplas, 2011). Organic production methods could be an attractive option for cotton farmers in Eastern Africa, because in this region, the use of chemical inputs is anyway virtually absent, the labor cost is low, and organic cotton has a higher sales price than conventional cotton. In order to scrutinize this option, we use microeconomic production theory and stochastic frontier models to thoroughly analyze organic cotton production in Tanzania. Our study is based on a unique data set of 180 small-scale organic cotton farmers in the Meatu region in Tanzania. This data set does not only provide information on input and output quantities, prices of traded inputs and output, as well as socio-economic and agronomic factors, but also on the shadow prices of all sparsely traded inputs, i.e. land, labor, and organic fertilizer. Hence, we can not only analyze productivity, technical efficiency, and scale efficiency, but also allocative efficiency, profitability, and competitiveness. Traditionally, the measurement of allocative efficiency assumed that all inputs can be freely traded at a given price on a perfectly functioning market. This assumption was relaxed by Tauer (1993) who suggested an approach that can additionally account for quasi-fixed input quantities, which cannot be adjusted in the short run. However, land, labor, and organic fertilizer can neither be traded on a perfect market nor are their quantities completely fixed for cotton production, but these input quantities can be adjusted by adjusting their use for other activities of the household. Hence, these inputs face non-constant shadow prices, which are determined by their opportunity costs. In order to account for the endogeneity of these shadow prices when calculating allocative efficiencies, we use the approach for modeling imperfect markets developed by Henning and Henningsen (2007). Based on our results, we can evaluate the current situation of organic cotton production as well as the potential and the directions for improving its profitability and competitiveness. Unfortunately, we did not finish the empirical analysis before the submission deadline. However, we will definitely include the results in our presentation at the conference.

Mgeni, Dotto; Henningsen, Arne

222

The Practice and Management Peculiarity of Farmer‘s Farm as Business Organization  

Digital Repository Infrastructure Vision for European Research (DRIVER)

There are used many organization management functions in farmer’s farm: farmer’s have to do accounting, hire workers and supervise them, make goods and create services, build image of their work. However evaluating farmer’s farm management more precisely, we have to face with lack of farmer’s farm as business organization management functions analysis in scientific literature. Also with uncertainty of farmer’s farm conception. Therefore, there was made analysis of farmer’s opinion...

Raupelyte?, Lina

2008-01-01

223

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

Directory of Open Access Journals (Sweden)

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

Théodore Munyuli

2011-08-01

224

Small-Scale Spray Releases: Orifice Plugging Test Results  

Energy Technology Data Exchange (ETDEWEB)

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.

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

2012-09-01

225

Internal dosimetry. Macroscopic, small-scale and microscopic perspectives  

International Nuclear Information System (INIS)

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

226

Observation and Analysis of Small-Scale Solar Magnetic Structure  

Science.gov (United States)

Properties of small-scale magnetic structures in the photosphere are analyzed in multi-spectral time-series image sets obtained at the 50 cm Swedish Solar Vacuum Telescope (SVST) on the island of La Palma, Spain. Several of the images are among the highest resolution images of the solar photosphere yet obtained. Sub-arcsecond-scale magnetic 'elements' are identified, segmented, and tracked using bright points found in very high spatial resolution G-band 4305 A filtergrams. Simultaneous images including Ca II K-line filtergrams, Fe I 6302 A magnetograms, and 4686 A broadband continuum filtergrams allow cross-wavelength comparison of properties. Angular resolution of the filtergrams is typically 0.25 '' and temporal resolution is in the range of 20-100 sec; magnetogram resolution approaches 0.3'' in some images and is generally below 0.5''. To above an 84% statistical confidence level, G-band bright points occur exclusively at sites of kilogauss, sub-arcsecond, magnetic flux concentrations in the photosphere; magnetic flux concentration is a necessary but not sufficient condition for the occurrence of G-band bright points. The measured distribution of magnetic element diameters in active region network is log-normal with a modal value of 220 km (0.3''). The smallest elements observed are 120 km (0.17'') in diameter; the largest are about 600 km (0.7'') in diameter. The average contrast with respect to quiet Sun of magnetic elements in the G-band is 30%: 2-3 times higher than the average continuum contrast. Magnetic element contrast does not vary with size within the size range of G-band bright point measurements. Average contrast increases with limbward heliocentric angle to a peak of about 80% at ? = /cos? = 0.3; there is evidence of a decrease with further increase in angle. Magnetic elements undergo a continual fragmentation/merging evolution driven by the granular convective flowfield of the photosphere; morphological time scales are on the order of 100 seconds. Velocities of individual elements range from 1-5 km s-1 with an RMS value of 2.4 km s-1. The range of motion is typically on granular and mesogranular scales (1000-2500 km) with an average value of 2100 km. Individual fragments from clusters have a characteristic lifetime on the order of the granulation correlation time (6-8 minutes). The lifetime of clusters associated with persistent sinks in the granular flowfield is on the order of hours. Classical statistical analysis of displacement versus time yields a diffusion coefficient for network magnetic elements of 224.8± 0.2 km s-1. In general, the results are inconsistent with the idea of small-scale magnetic flux in the photosphere being contained in stable, isolated, 'flux tubes' and emphasize the need for better understanding of the formation and the thermal (and? non-thermal) heating of magnetic regions in the photosphere.

Berger, Thomas Edward

1997-05-01

227

Small scale turbulence in a plane mixing layer  

Science.gov (United States)

Two measures of small scale turbulence, viscous dissipation and a direct count of the random fine eddies which dissipate energy, were correlated to the large scale coherent motions in a plane mixing layer. Experiments were conducted in a low speed wind tunnel at moderate Reynolds number with laminar boundary layers separating from both the high and low speed sides. Extensive x- and parallel-wire measurements yielded three-component velocity data taken point by point in a plane normal to the freestream. The location of the large scale coherent motions was determined by spatially differentiating the long-time averages of these data. The primary spanwise vortex was identified from Delta U/Delta y while the secondary streamwise ribs were obtained from Delta V/Delta z, where Delta y and Delta z represent the spacing between data points in the cross-stream and spanwise directions, respectively. It will be demonstrated how Delta U/Delta z identifies the rib locations, as well. The data, moreover, were taken so that the fine-scale eddies, those whose length scale corresponds exactly to the peak in the 3-D dissipation spectrum, were resolved both spatially and temporally. These 'dissipative' eddies were identified by a novel technique, the peak-valley-counting (PVC) method. Several of the viscous dissipation terms were also calculated. The fine-scale eddy population distributions and the measures of viscous dissipation correlated extremely well. Indeed, the 'dissipative' eddies dissipate the energy, and the PVC method identifies them. Both sets of distributions peak in the core of the spanwise vortex, and are independent of the streamwise ribs at this downstream location.

Foss, Judith Kathleen

1994-03-01

228

Propulsion engineering study for small-scale Mars missions  

Energy Technology Data Exchange (ETDEWEB)

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

Whitehead, J.

1995-09-12

229

Modelling of oxycoal combustion in a small scale test facility  

Energy Technology Data Exchange (ETDEWEB)

CO{sub 2} is generated during combustion of carbonaceous fuels, and thus contributing to approximately 60% of the enhanced greenhouse gas effect. Recently, Oxycoal or O{sub 2}/CO{sub 2} recycle combustion followed by post-combustion CO{sub 2} sequestration has gained a justified interest as an option for a significant and relatively quick reduction of emissions from fossil fuel power generation, while taking advantage of the existing power plant infrastructure. The combustion of pulverised coal in an O{sub 2}/CO{sub 2}-atmosphere, however, provides new challenges to the combustion specialists. Without oxygen enrichment, the Oxycoal flame is characterised by much lower temperatures, compared to air combustion and limited flame visibility. This results in changes in the combustion rates and in NOx formation. Computational Fluid Dynamics (CFD), being a powerful investigation tool, can provide detailed information, which is necessary to understand these phenomena, thus helping us to develop and successfully run an Oxycoal combustion process. This paper presents a prior numerical study of a small scale pulverised fuel swirl burner (80kW), specially designed for Oxycoal combustion. First, a single particle test case was calculated, thus assessing the effect of high CO{sub 2} volume concentration (compared to air conditions) on the particle temperature and on the rates of the heterogeneous reactions. Further, three pulverised coal flames were numerically investigated: one in air and two in O{sub 2}/CO{sub 2}. The obtained numerical results were compared and analysed. The influence of gasification reactions and burner operation conditions on the flame stabilisation is shown. Conclusions concerning the achievement of a stable Oxycoal flame at O{sub 2} volume concentration equal to the air O{sub 2}% were derived. 15 refs., 7 figs., 6 tabs.

D. Toporov; S. Tschunko; J. Erfurth; R. Kneer [RWTH Aachen University, Aachen (Germany). Institute of Heat and Mass Transfer

2006-07-01

230

ARCADE small-scale docking mechanism for micro-satellites  

Science.gov (United States)

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

Boesso, A.; Francesconi, A.

2013-05-01

231

Small Scale Cold Traps on Airless Planetary Bodies  

Science.gov (United States)

Lacking an atmosphere to transport heat, temperatures on airless bodies are primarily controlled by latitude and local time. However, local topography strongly affects temperatures at the surface and in the subsurface by changing the intensity and timing of insolation. In the case of low-obliquity bodies such as Mercury and the Earth’s moon, topography near the poles casts perennial shadows where volatiles such as water ice may be cold-trapped for billions of years. Prior studies have focused primarily on large contiguous cold traps > 1 km resolvable by instruments in lunar orbit. In this investigation, we used infrared measurements of the Moon, thermal models, and a statistical rough surface model to show that such cold traps may exist on a vast range of scales, from the largest impact craters, down to the skin depth of the diurnal temperature oscillation. The extremely insulating nature of planetary regolith leads to extreme temperature gradients and shallow diurnal skin depths. For example, the lunar 29-day diurnal temperature oscillation is damped to ~1% at a depth of 0.5 m. Therefore, at latitudes > 60° where perennial shadow exists, cold traps as small as a few tens of centimeters could exist. As two test cases, we calculated the fractional surface areas on the Moon (obliquity = 1.6°) and Ceres (3-5°) where temperatures remain calculated fractional areas where subsurface temperatures are < 145 K, such that subsurface ice deposits are stable on similar timescales. Finally, we will discuss the implications of these proposed small-scale cold traps for other airless bodies, including asteroids and giant planet satellites.

Hayne, Paul O.; Aharonson, O.; Williams, J.; Siegler, M. A.; Greenhagen, B. T.; Bandfield, J.; Vasavada, A. R.; Paige, D. A.; Diviner Lunar Radiometer Science Team

2013-10-01

232

Estimation of GPS instrumental biases from small scale network  

Science.gov (United States)

With 4 GPS receivers located in the equatorial anomaly region in southeast China, this paper proposes a grid-based algorithm to determine the GPS satellites and receivers biases, and at the same time to derive the total electron content (TEC) with time resolution of 15 min and spatial resolution of 1° by 3.5° in latitude and longitude. By assuming that the TEC is identical at any point within a given grid block and the biases do not vary within a day, the algorithm arranges unknown biases and TECs with slant path TEC from the 4 receivers’ observations into a set of equations. Then the instrumental biases and the TECs are determined by using the least squares fitting technique. The performance of the method is examined by applying it to the GPS receiver chain observations selected from 16 geomagnetically quiet days in four seasons of 2006. It is found that the fitting agrees with the data very well, with goodness of fit ranging from 0.452 TECU to 1.914 TECU. Having a mean of 0.9 ns, the standard deviations for most of the GPS satellite biases are less than 1.0 ns for the 16 days. The GPS receiver biases are more stable than that of the GPS satellites. The standard deviation in the 4 receiver bias is from 0.370 ns to 0.855 ns, with a mean of 0.5 ns. Moreover, the instrumental biases are highly correlated with those derived from CODE and JPL with independent methods. The typical precision of the derived TEC is 5 TECU by a conservative estimation. These results indicate that the proposed algorithm is valid and qualified for small scale GPS network.

Ma, Guanyi; Gao, Wei; Li, Jinghua; Chen, Yanhong; Shen, Hua

2014-09-01

233

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

International Nuclear Information System (INIS)

A number of experiments have been performed with blast waves arising from the ignition of homogeneous and well defined mixtures of methane, oxygen and nitrogen, contained within spherical balloons with controlled initial dimensions. In the initial small scale experiments pressure characteristics, ground reflection phenomena and pressure distribution on box like obstacles were studied. Both configurations with one box and two closely spaced boxes have been considered, and a wave-wave interaction phenomenom was observed in the case of closely spaced obstacles. Main emphasis has been placed on the half scale field experiments. In these, the maximum flame speed has been of the order of 100 m/s, resulting in positive peak pressures of 50-100.102Pa in 5 - 10 m distance from the source. The explosion process was found to be reasonable symmetric. The attenuation of the blast wave due to vegetation and the influence of obstacles as banks, walls and houses on the pressure field have been investigated. The presence of the bank and the house was felt in a zone with a length corresponding to a typical dimension of the obstacles, whereas the overall pressure field is shown to be unaffected by the type of obstacles and vegetation investigated. For the wall and house, reflection factors have been established, and some variation over the surface has been measured. The scatter of the pressure measurements is estimated for stable, neutral and unstable atmospheric conditions, and an attempt to determine the ground reflection factor has been performed. Finally the accelerations of a house exposed to the blast wave have been examined

234

Universality of the Small-Scale Dynamo Mechanism  

Science.gov (United States)

We quantify possible differences between turbulent dynamo action in the Sun and the dynamo action studied in idealized simulation. For this purpose we compare Fourier-space shell-to-shell energy transfer rates of three incrementally more complex dynamo simulations: an incompressible, periodic simulation driven by random flow, a simulation of Boussinesq convection, and a simulation of fully compressible convection that includes physics relevant to the near-surface layers of the Sun. For each of the simulations studied, we find that energy is transferred from the turbulent flow to the magnetic field from length-scales in the inertial range of the energy spectrum. The addition of physical effects relevant to the solar near-surface layers, including stratification, compressibility, partial ionization, and radiative energy transport, does not appear to affect the nature of the dynamo mechanism. The role of inertial-range shear stresses in magnetic field amplification is independent from outer-scale circumstances, including forcing and stratification. Although shell-to-shell energy transfer functions have similar properties in each simulation studied, the saturated states of these simulations are not universal; the flow at the driving scales is a significant source of energy for the magnetic field. The mechanism of energy-transfer in kinematic small-scale dynamo simulations exhibits universal properties. This work has been supported by the Max-Planck Society in the framework of the Interinstitutional Research Initiative Turbulent transport and ion heating, reconnection and electron acceleration in solar and fusion plasmas of the MPI for Solar System Research, Katlenburg-Lindau, and the Institute for Plasma Physics, Garching (project MIF-IF-A-AERO8047).

Pietarila Graham, Jonathan; Moll, R.; Pratt, J.; Cameron, R.; Mueller, W.; Schuessler, M.

2011-05-01

235

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

Directory of Open Access Journals (Sweden)

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

Oboro, O. G.

2011-12-01

236

Experimental investigations of the vertically loaded small scale bored piles  

Directory of Open Access Journals (Sweden)

Full Text Available At present, while evaluating bored piles load capacity in clay soils by CPT data, the depth of active area below the end face plane, within which the averaging of CPT values takes place, is taken as different in different Codes. Thus, for instance, in native Codes and Recommendations the depth of active area is taken from 2 to 4 pile diameters. In foreign Codes such as Belorussian, the depth of active area is taken up to 4 pile diameters and in European Codes - within 0,8-4 pile diameters. In order to specify the regularities of active area forming at different stages of loading, in-situ experimental investigations of large scale models have been carried out. At the test site, two small scale bored piles with the diameter of 130 mm were penetrated into the soil to the depth of 1100 m. The investigations were carried out in two stages: the first - pile static test with measuring of soil vertical displacements with the help of deep marks; the second - digging out soil around the pile and soil sampling at different depths. According to the results of the investigations carried out, the depth of the active area while reaching the limit state was determined to be about two pile diameters. With significant pile settlements (more than 0,58 d, the dimensions of this area do not exceed three pile diameters below the end face plane, and two diameters to the side from the pile axis. Within the lateral surface the significant variation of soil physical characteristics appears to be at the distance not less than 0,4 pile diameter from the lateral surface. Due to investigations’ results, it can be noted that in case of bored pile load less than the limit one, the depth of the active area is about two pile diameters. When the pile reaches its limit state, that provokes significant settlements, zone of compaction does not exceed three diameters to the depth and two diameters to the side from the pile axis.

Glazachev Anton Olegovich

2014-04-01

237

Small-scale soil moisture determination with GPR  

Science.gov (United States)

The knowledge of topsoil moisture distribution is an important input for modelling water flow and evapotranspiration which are essential processes in hydrology, meteorology, and agriculture. All these processes involve non-linear effects and thus the small-scale variability of input parameters play an important role. Using smoothed interpolations instead can cause significant biases. Lateral soil moisture distribution can be sensed by different techniques at various scales whereby geophysical methods provide spatial information which closes the gap between point measurements by classical soil scientific methods and measurements on the field or regional scale by remote sensing. Ground-penetrating radar (GPR) can be used to explore soil moisture on the field scale as propagation of electromagnetic waves is correlated to soil water content. By determining the velocity of the ground wave, which is a guided wave travelling along the soil surface, we can sense soil water content. This method has been applied to determine topsoil moisture for several years. We present a new groundwave technique which determines the velocity in between two receiving antennas which enables a higher lateral resolution (approx. 10 cm) compared to classical groundwave technique (half meter and more). We present synthetic data from finite-differences (FD) calculations as well as data from a sandbox experiment carried out under controlled conditions to demonstrate the performance of this method. Further, we carried out field measurements on two sites on a sandy soil which is used as grassland. The measurements were carried out in late summer at dry soil conditions. Soil moisture on the first site shows an isotropic pattern with correlation lengths of approx. 35 cm. We think this natural pattern is governed by rout distribution within the soil and the water uptake of vegetation. On the second site, soil moisture distribution shows a regular stripe pattern. As the land has been used as agricultural crop land until two years before the measurements were carried out, this anisotropy is obviously caused by the former cultivation of the land. Finally, we present a second technique to determine moisture of the topsoil by GPR using the same principle as remote sensing: the reflection of electromagnetic waves at the soil surface and determination of reflection amplitude. We use a 1 GHz horn antenna that is operated 0.5 m above the ground surface. As this method is based on a completely different physical principle than the first one, it provides an independent revision of our results. Even though, lateral resolution is not that high as when using the groundwave technique and the depth of investigation is not exactly the same, we get similar results showing the same pattern and characteristics at both sites.

Igel, Jan; Preetz, Holger

2010-05-01

238

Small-scale chromospheric jets above a sunspot light bridge  

Science.gov (United States)

Context. The chromosphere above sunspot umbrae and penumbrae shows several different types of fast dynamic events such as running penumbral waves, umbral flashes, and penumbral microjets. Aims: The aim of this paper is to identify the physical driver responsible for the dynamic and small-scale chromospheric jets above a sunspot light bridge. Methods: High-resolution broadband filtergrams of active region NOAA 11271 in Ca ii H and G band were obtained with the Solar Optical Telescope on board Hinode. We identified the jets in the Ca ii H images using a semi-automatic routine and determined their length and orientation. We applied local correlation tracking (LCT) to the G-band images to obtain the photospheric horizontal velocity field. The magnetic field topology was derived from a Milne-Eddington inversion of a simultaneous scan with the Spectropolarimeter. Results: 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 that is bright against the dark umbral background. Most of the jets have apparent lengths of less than 1000 km and about 30% of the jets have lengths between 1000-1600 km. The jets are oriented within ±35° to the normal of the spine of the light bridge. Most of them are clustered near the central part of the light bridge within a 2'' area. The jets are seen to move rapidly along the light bridge and many of them cannot be identified in successive images taken with a 2 min cadence. The jets are primarily located on one side of the light bridge and are directed into the umbral core. The Stokes profiles at or close to the location of the blobs on the LB exhibit both a significant net circular polarization and multiple components, including opposite-polarity lobes. The magnetic field diverges from the light bridge towards the umbral cores that it separates. The LCT reveals that in the photosphere there is a predominantly uni-directional flow with speeds of 100-150 m s-1 along the light bridge. This unidirectional flow is interrupted by a patch of weak or very small motions on the light bridge which also moves along the light bridge. Conclusions: The dynamic short-lived chromospheric jets above the LB seem to be guided by the magnetic field lines. Reconnection events are a likely trigger for such phenomenon since they occur at locations where the magnetic field changes orientation sharply and where we also observe isolated patches of opposite-polarity magnetic components. We find no clear relation between the jets and the photospheric flow pattern.

Louis, Rohan E.; Beck, Christian; Ichimoto, Kiyoshi

2014-07-01

239

FARMERS SUICIDE : CAUSES & REMEDIES  

Directory of Open Access Journals (Sweden)

Full Text Available In the today economical structure creating paradox or line “Excellent far, medium business and subordinate service. Since ancient age in India most of changes in political views but in Rural society and economical system of self sufficient and self-dependence intact till Britisher arrival. In British rule drain process Rural aria and destroy the farms, and related Business on the farm are destroy. In this period most of the farmer expoted by the natural adversity and critical condition of famers not registrate. But last decennial farmers suicide statistical data seen creating fear in mind.

B. S. Pimple

2014-03-01

240

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

Directory of Open Access Journals (Sweden)

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

Shijun Yang

2009-02-01

 
 
 
 
241

Farmers' markets and shops  

Jul 1, 2006 ... Farmers' markets, farm shops and assurance schemes offer an opportunity to sell \\food and other produce to the general public and add value to products. For \\further details see: ... The import and exports pages provide information and \\guidance on: Animal imports and ... Page last modified: 1 July 2006

242

Small-Scale Spray Releases: Initial Aerosol Test Results  

Energy Technology Data Exchange (ETDEWEB)

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.

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

243

Small-scale expression of proteins in E. coli.  

Science.gov (United States)

Proteins participate in virtually every cellular activity, and a knowledge of protein function is essential for an understanding of biological systems. However, protein diversity necessitates the application of an array of in vivo and in vitro approaches for characterization of the functional and biochemical properties of proteins. Methods that enable production of proteins for in vitro studies are critical for determination of the molecular, kinetic, and thermodynamic properties of these molecules. Ideally, proteins could be purified from the original source; however, the native host is often unsuitable for a number of reasons. Consequently, systems for heterologous protein production are commonly used to produce large amounts of protein. Heterologous expression hosts are chosen using a number of criteria, including genetic tractability, advantageous production or processing characteristics (secretion or posttranslational modifications), or economy of time and growth requirements. The subcloning process also provides an opportunity to introduce purification tags, epitope tags, fusions, truncations, and mutations into the coding sequence that may be useful in downstream purification or characterization applications. Bacterial systems for heterologous protein expression have advantages in ease of use, cost, short generation times, and scalability. These expression systems have been widely used by high-throughput protein production projects and often represent an initial experiment for any expression target. Escherichia coli has been studied for many years as a model bacterial organism and is one of the most popular hosts for heterologous protein expression (Terpe, 2006). Its protein production capabilities have been intensively studied, and the ease of genetic manipulation in this organism has led to the development of strains engineered exclusively for use in protein expression. These resources are widely available from commercial sources and public repositories. Despite these advantages, many targets are unsuitable for expression in E. coli, and attempts will not yield protein that can be utilized in downstream applications. A thorough understanding of the protein target, the requirements of the final application, and available tools are all essential for planning a successful expression experiment. This protocol is designed to optimize expression and solubility using an E. coli host and expression vector with an IPTG-inducible T7 promoter. The general features of the method are easily extended to other organisms and expression systems. Small-scale expression cultures are used to identify the optimum expression parameters for a given target. Thorough analysis of the total cell content and soluble fraction is used to screen out failed targets and those unlikely to succeed in large-scale purification cultures. The protocol listed here can be used in individual tubes for a small number of targets or adapted for use in 48-well plates for high throughput applications (Abdullah et al., 2009). Using the same culture for initial expression analysis and solubility analysis reduces variability between expression trials and saves the time required to produce separate cultures. PMID:24423272

Zerbs, Sarah; Giuliani, Sarah; Collart, Frank

2014-01-01

244

Small-Scale Spray Releases: Initial Aerosol Test Results  

Energy Technology Data Exchange (ETDEWEB)

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.

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

245

(15)N tracer application to evaluate nitrogen dynamics of food webs in two subtropical small-scale aquaculture ponds under different managements.  

Science.gov (United States)

Small, semi-intensively managed aquaculture ponds contribute significantly to the food security of small-scale farmers around the world. However, little is known about nutrient flows within natural food webs in such ponds in which fish production depends on the productivity of natural food resources. (15)N was applied as ammonium at 1.1 and 0.4 % of total nitrogen in a traditionally managed flow-through pond and a semi-intensively managed stagnant pond belonging to small-scale farmers in Northern Vietnam and traced through the natural food resources over 7 days. Small-sized plankton (1-60 ? m) was the dominant pelagic biomass in both ponds with higher biomass in the stagnant pond. This plankton assimilated major portions of the applied tracer and showed a high sedimentation and turnover rate. High re-activation of settled nutrients into the pelagic food web was observed. The tracer was removed more quickly from the flow-through pond than from the stagnant pond. A steady nutrient supply could increase fish production. PMID:24995524

Pucher, Johannes; Mayrhofer, Richard; El-Matbouli, Mansour; Focken, Ulfert

2014-12-01

246

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

Directory of Open Access Journals (Sweden)

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

Agomuo Florence Ozioma

2012-03-01

247

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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. Final...

Olatunji Eniola Sule

2013-01-01

248

FARMERS SUICIDE : CAUSES & REMEDIES  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In the today economical structure creating paradox or line “Excellent far, medium business and subordinate service. Since ancient age in India most of changes in political views but in Rural society and economical system of self sufficient and self-dependence intact till Britisher arrival. In British rule drain process Rural aria and destroy the farms, and related Business on the farm are destroy. In this period most of the farmer expoted by the natural adversity and critica...

Pimple, B. S.

2014-01-01

249

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

DEFF Research Database (Denmark)

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.

LilleØr, Helene Bie; Larsen, Anna Folke

2013-01-01

250

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

Energy Technology Data Exchange (ETDEWEB)

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)

1980-06-01

251

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

Energy Technology Data Exchange (ETDEWEB)

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

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

2012-02-15

252

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

DEFF Research Database (Denmark)

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.

Larsen, Anna Folke; LilleØr, Helene Bie

2014-01-01

253

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

Scientific Electronic Library Online (English)

Full Text Available SciELO South Africa | Language: English Abstract in english This paper presents a case study of large- and small-scale irrigators negotiating for access to water from Nduruma River in the Pangani River Basin, Tanzania. The paper shows that despite the existence of a formal statutory water permit system, all users need to conform to the existing local rules 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.

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

2012-01-01

254

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

Scientific Electronic Library Online (English)

Full Text Available SciELO South Africa | Language: English Abstract in english This paper presents a case study of large- and small-scale irrigators negotiating for access to water from Nduruma River in the Pangani River Basin, Tanzania. The paper shows that despite the existence of a formal statutory water permit system, all users need to conform to the existing local rules 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.

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

255

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

Energy Technology Data Exchange (ETDEWEB)

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

1980-07-01

256

A new framework for analyzing the effects of small scale inhomogeneities in cosmology  

CERN Document Server

We develop a new, mathematically precise framework for treating the effects of nonlinear phenomena occurring on small scales in general relativity. Our approach is an adaptation of Burnett's formulation of the "shortwave approximation", which we generalize to analyze the effects of matter inhomogeneities as well as gravitational radiation. Our framework requires the metric to be close to a "background metric", but allows arbitrarily large stress-energy fluctuations on small scales. We prove that, within our framework, if the matter stress-energy tensor satisfies the weak energy condition (i.e., positivity of energy density in all frames), then the only effect that small scale inhomogeneities can have on the dynamics of the background metric is to provide an "effective stress-energy tensor" that is traceless and has positive energy density---corresponding to the presence of gravitational radiation. In particular, nonlinear effects produced by small scale inhomogeneities cannot mimic the effects of dark energy....

Green, Stephen R

2010-01-01

257

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

Directory of Open Access Journals (Sweden)

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

Mumtaz Ali Junejo

2008-09-01

258

Free-Hand Small-Scale Maps: Activities for Cognitive Mapping.  

Science.gov (United States)

Suggests that small-scale mapping activities can be used in geography courses to help students understand geographic concepts such as latitude, longitude, situation, relative location, and national boundaries. (Author/DB)

Saveland, Robert N.

1978-01-01

259

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Harjula, Nina

2009-01-01

260

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Mihaiu, Marian; Lapusan, Alexandra; Mihaiu, Romolica; Dan, Sorin D.; Jecan, Carmen

2012-01-01

 
 
 
 
261

Women's occupational health working in small-scale agriculture in South Africa  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In developing economies women’s contributions are in agriculture. Trends indicate that women’s participation in small-scale agriculture is increasing. On the Makhatini Flats in northern KwaZulu-Natal intensive small-scale farming takes place with > 4 000 women involved. A cross-sectional study on the Irrigation Scheme and Drylands areas of the Makhatini Flats described and compared occupational activities, crop production, pesticide use and adverse health outcomes among women working in s...

Naidoo, S.

2011-01-01

262

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 b...

Mumtaz Ali Junejo; Dr. Muhammad Nawaz Chand

2008-01-01

263

The risks of inclusion: shifts in governance processes and upgrading opportunities for cocoa farmers in Ghana  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This PhD study provides a detailed description and analysis of upgrading opportunities for small-scale cocoa farmers in Ghana. It shows how and why producers do, or do not, benefit from being inserted in a global value chain that is increasingly driven by multinational cocoa processors and chocolate manufacturers. The study contributes to the recent discussions on hybrid governance structures, in which both public and private actors play a role. Ghana provides a unique case because, unlike...

2010-01-01

264

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

Directory of Open Access Journals (Sweden)

Full Text Available 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 on science and technology parks' performance in themost of countries demonstrate the effective and positive roles of these institutions in entrepreneurship,technology and economical development, increasing technological innovation and employment. This paperinvestigates the innovation in small scale industries which is settled in science parks of Iran. The primary datacollected from questionnaire and has been analyzed through using SPSS version 16 software. The results of thisstudy indicate that there are some factors that accelerate innovation within firms. Beside small scale industrieshas a positive and significant effect on innovation and the range of innovation in small scale industries is morethan other firms.

Alireza Fazlzadeh

2010-09-01

265

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

DEFF Research Database (Denmark)

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

JØnsson, Jesper Bosse; Fold, Niels

2009-01-01

266

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)

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.

Jonah, Ikoku John

2014-04-01

267

Partnerships between utilities and small-scale providers: Delegated management in Kisumu, Kenya  

Science.gov (United States)

Increasingly, partnerships between small-scale providers and formal utilities are being promoted as an alternative model of infrastructure development and service provision. This paper analyzes the potential of such a model for bridging the gap in service provision in peri-urban areas. The model, which this article focuses on, is the delegated management model, which has been implemented in Kisumu, Kenya. In this model a formal utility entered into contracts with multiple small-scale providers to distribute water to an informal settlement. In this arrangement, the water utility sells bulk water to the small-scale providers and these then distribute the water to an area covering about 120 connections for each provider. The research finds that the arrangement in Kisumu has met with mixed results. On the one hand, the arrangement led to considerable service expansion and to service improvements for those not connected to the network. Also, the formal utility benefited from the fact that they generated additional revenue by selling bulk water to the small-scale providers. The arrangement has also generated employment for those working for the small-scale providers. On the other hand, experiences so far, show that some challenges need to be addressed before the partnership arrangement becomes truly sustainable. For some providers corruption seems to be a problem as funds have been misappropriated. Also, the utility has not upheld the agreement to transfer all ‘old connections’ to the small-scale providers. A particularly worrying feature is that in low-income areas of Nyalenda, the customers of kiosks run by the small-scale providers pay three times more for their water than households who have an in-house connection.

Schwartz, Klaas; Sanga, Anthony

268

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

Directory of Open Access Journals (Sweden)

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.

Mytnyk, Ulyana Mykolayivna

2011-11-01

269

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.

270

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

Science.gov (United States)

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.

King, S.; Samuel, H.

2012-04-01

271

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

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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.

Xavier Mhike

2012-04-01

272

Seropositivity and risk factors for Brucella in dairy cows in urban and peri-urban small-scale farming in Tajikistan.  

Science.gov (United States)

In this cross-sectional study, we assessed and mapped the seroprevalence of brucellosis in small-scale dairy farming in an urban and peri-urban area of Tajikistan and investigated factors associated with seropositivity. As urban and peri-urban farming is both an opportunity to improve the livelihood for small-scale farmers and a potential public health hazard, studies are warranted to reveal possible peculiarities in the epidemiology of brucellosis in this type of dairy farming. In total, 904 cows of breeding age belonging to 443 herds in 32 villages were serologically tested with indirect enzyme-linked immunosorbent assay (ELISA) and positive samples confirmed with competitive ELISA. Two logistic regression models were used to investigate an association between seropositivity and risk factors at herd and individual level. The herd and individual seroprevalences were 4.1 and 2.0 %, respectively. Herds with a history of abortions were found to be associated with seropositivity [odds ratio (OR)?=?5.3; 95 % confidence interval (CI), 1.3-21.3]. Large herds with more than eight cattle were more likely to be seropositive compared to smaller herds with one to two cattle (OR?=?13.9; 95 % CI, 1.6-119). The number of calves produced per cow (indicating age) was found to be associated with seropositivity. Younger cows with one to two produced calves were less likely to be seropositive compared to older cows with more than six produced calves (OR?=?0.24; 95 % CI, 0.06-1.0). Neither introduction of new cattle to the herd nor communal grazing was associated with seropositivity. This study shows that infection with Brucella (1) is present in small-scale urban and peri-urban dairy farming in Tajikistan and (2) has significant negative effects on reproductive performance in this farming system and (3) that some previously known risk factors for seropositivity in rural farming system were absent here. PMID:24414248

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

2014-03-01

273

Economic Underdevelopment and Total Factor Growth in Small Scale Industries: Some Evidences from India  

Directory of Open Access Journals (Sweden)

Full Text Available Globalization of Indian economy and fast and large industrialization questioned the sustainability and endurance of small scale industries (SSIs from 1991. In this regard productivity and performance is remaining an issue that needs analysis for their development. However economic underdevelopment is remain a problem for the development of small scale industries. In this paper an attempt has been made to examine the productive performance of in small scale industries in India in underdeveloped areas with special reference to Assam. The findings of the study suggest the Total Factor Productivity (TFP of SSIs in underdeveloped areas seemed to be growing steadily over the time. The overall linear trend line of TFPG of SSIs of India indicates a declining trend over the periods from 1973- 74 to 2001-2002.

Hemanta Saikia

2011-09-01

274

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

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

Li Ming

2013-03-01

275

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

Energy Technology Data Exchange (ETDEWEB)

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

Buxton, Abbi

2013-02-15

276

Small-scale martian polygonal terrain: Implications for liquid surface water  

Science.gov (United States)

Images from the Mars Orbiter Camera (MOC) through August 1999 were analyzed for the global distribution of small-scale polygonal terrain not clearly resolved in Viking Orbiter imagery. With very few exceptions, small-scale polygonal terrain occurs at middle to high latitudes of the northern and southern hemisphere in Hesperian-age geologic units. The largest concentration of this terrain occurs in the Utopia basin in close association with scalloped depressions (interpreted as thermokarst) and appears to represent an Amazonia event. The morphology and occurence of small polygonal terrain suggest they are either mud desiccation cracks or ice-wedge polygons. Because the small-scale polygons in Utopia and Argyre Planitiae are associated with other cold-climate permafrost or glacial features, an ice-wedge model is preferred for these areas. Both cracking mechanisms work most effectively in water- or ice-rich finegrained material and may imply the seasonal or episodic existence of liquid water at the surface.

Seibert, N. M.; Kargel, J. S.

2001-01-01

277

The need for small-scale turbulence in atmospheres of substellar objects  

CERN Document Server

Brown dwarfs and giant gas planets are substellar objects whose spectral appearance is determined by the chemical composition of the gas and the solids/liquids in the atmosphere. Atmospheres of substellar objects possess two major scale regimes: large-scale convective motions + gravitational settling and small-scale turbulence + dust formation. Turbulence initiates dust formation spot-like on small scale, while the dust feeds back into the turbulent fluid field by its strong radiative cooling. Small, imploding dust containing areas result which eventually become isothermal. Multi-dimensional simulations show that these small-scale dust structures gather into large-scale structures, suggesting the formation of clouds made of dirty dust grains. The chemical composition of the grains, and thereby the chemical evolution of the gas phase, is a function of temperature and depends on the grain's history.

Helling, C

2005-01-01

278

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

Directory of Open Access Journals (Sweden)

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

A. Higuchi

2010-12-01

279

Small-scale biomass CHP using gasa turbines: a scoping study  

International Nuclear Information System (INIS)

Various options for small-scale (up to 250 KWe) Combined Heat and Power (CHP) plants evaluated in this scoping study. Plants using small gas turbines, and able to use biomass fuels when available are included. Three detailed case studies of small-scale biomass CHP plants are compared to match specific technical options with customer requirements. The commercial development of such biomass-fired CHP units, using gas turbines, is shown to be economically viable depending on fuel costs and the continuation of existing financial incentives. (UK)

280

Analysis on the detection performance of BOTDR in small-scale precision engineering  

Science.gov (United States)

In this thesis, the authors discuss the detection performance of the small-scale precision engineering with the Brillouin scattering light on the base of experiments. The authors made the measurements using the traditional Strain Distribution Gauge and optical fiber scattering light shift equipment AQ8603 and obtained two results. The authors compared and analyzed the data and made the conclusion that the BOTDR technology is not suitable for the small-scale Precision Engineering. The wiring methods and their effects to detection performance are also been discussed in this thesis.

Wang, Shuai; Luan, Lijun

2013-12-01

 
 
 
 
281

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

CERN Document Server

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

Connaughton, Colm; Quinn, Brenda

2010-01-01

282

Experimental investigation of spatiotemporal evolution of femtosecond laser pulses during small-scale self-focusing  

Science.gov (United States)

Small-scale self-focusing (SF) causes rapid increase in the partial spatial intensity, breaking up the spatial profile of the beam into an intensity increasing zone (IZ) and a non-increasing zone (NIZ). We measure the evolutions of the pulse width at the IZ and NIZ with small-scale SF, and our results show that the pulse width at the IZ becomes narrower with increasing partial spatial intensity. The pulse width at the NIZ is almost unchanged with increasing laser power. We find that our experimental results are in good agreement with an approximate theoretical analysis.

Deng, Y. B.; Fu, X. Q.; Tan, C.; Yang, H.; Deng, S. G.; Xiong, C. X.; Zhang, G. F.

2014-03-01

283

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)

284

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

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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.

Ojenike Joseph Ojenike

2012-11-01

285

Small-scale waste-to-energy systems: A state-of-the-art report  

Science.gov (United States)

For industry and local government, small scale waste to energy systems represent an increasingly attractive option to enhance energy security, control energy costs, generate revenues and alleviate landfill constraints. Projects are characterized by: a mix of modular and waterwall systems; small and medium size industrial steam customers; a nascent interest in cogeneration; the utilization of a variety of public financing instruments; and growing vendor involvement in facility operations. Experience also points to the pivotal role of one or a few persistent individuals during the project implementation process. Recent operating history is likely to provide the foundation for steady growth in the number of small scale systems during the next decade.

White, A. L.

1982-02-01

286

Farmer Ted Goes Natural  

CERN Document Server

A traditional "Farmer Ted" calculus problem is to minimize the perimeter of a rectangular chicken coop given the area N, so that as little as possible will be spent on the fencing. But what if N is an integer, and we are only allowed to consider rectangles with integer side lengths? Often it will be more cost-effective to build a coop with area smaller than N, where the measure of cost-effectiveness is the ratio of the area to the perimeter. Those numbers N that are the areas of rectangles that are more cost-effective than any smaller rectangle are dubbed "almost-squares", in deference to our intuition that such numbers ought to be the product of two nearly equal factors. This paper investigates the characterization and distribution of the almost-squares. It is shown that almost-squares can be equivalently described in a surprisingly elegant way, and that computing whether a number is an almost-square and computing the least almost-square not exceeding N can be done surprisingly efficiently (much faster than ...

Martin, G

1999-01-01

287

Farmer Suicide and Community Policing  

Directory of Open Access Journals (Sweden)

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

Purnanand. N. Sangalad

2012-08-01

288

Auto Farmer Using Renewable Energy  

Directory of Open Access Journals (Sweden)

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 .

TANAY CHOWDHURY

2013-02-01

289

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

Directory of Open Access Journals (Sweden)

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

Margaret Njeri Gathura

2013-09-01

290

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)

291

Assessing Arsenic Removal by Metal (Hydr)Oxide Adsorptive Media Using Rapid Small Scale Column Tests  

Science.gov (United States)

The rapid small scale column test (RSSCT) was use to evaluate the the performance of eight commercially available adsorptive media for the removal of arsenic. Side-by-side tests were conducted using RSSCTs and pilot/full-scale systems either in the field or in the laboratory. ...

292

Measurement of Small-Scale CMB Anisotropy with the Viper Telescope  

Science.gov (United States)

Viper is a 2-meter off-axis telescope designed to measure small-scale anisotropy in the Cosmic Microwave Background Radiation. The spatial sensitivity of this instrument (50 < l < 800) was chosen to provide maximum discrimination between competing cosmological models. We present data taken with a 40 GHz HEMT receiver at Amundsen-Scott Station, Antarctica, and discuss future applications of the instrument.

Griffin, G.; Peterson, J.; Newcomb, M.; Alvarez, D.; Cantalupo, C.; Morgan, D.; Vincent, M.; Miller, K.

1998-05-01

293

Nature of Small-Scale Jets On the Solar Chromosphere Revealed with Hinode  

Science.gov (United States)

The Solar Optical Telescope aboard Hinode has revealed the nature of small-scale jets of the solar chromosphere. Jet-like structures are ubiquitous there not only in the quiet Sun but also in active region and even in sunspot penumbra. They are likely to play an important role in maintaining the energy balance of the local atomsphere and the mass balance of the corona. High time and spatial resolution observations for the first time have revealed that the small-scale jets consist of highly dynamic multi-threads of as thin as a few tenths of arcsecond and shows prominent lateral movement or oscillation with rotation on its axis during its life. The fine structure and lateral motion indicate that the small-scale can be ejected by magnetic reconnection at footpoints. Since the most small-scale jets emanate from seemingly uni-polar magnetic region and the relevant magnetic reconnection should take place in unresolved spatial scale contrary to the larger-scale jets in which bipole magnetic structures are found at their footpoints. We discuss multi-scale structures of the chromospheric jets.

Suematsu, Y.

2008-12-01

294

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

International Nuclear Information System (INIS)

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

295

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

Science.gov (United States)

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.

Klimchuk, James

2010-01-01

296

New limits to the small scale fluctuations in the cosmic background radiation  

International Nuclear Information System (INIS)

The VLA has been used at 4.9 GHz to observe a small region of sky in order to extend the radio source count to low flux density (Fomalont et al., these proceedings) and to look for small scale fluctuations in the 2.7 K cosmic microwave background radiation. (Auth.)

297

Physico-chemical treatment of wastewater from clusters of small scale cotton textile units.  

Science.gov (United States)

Small scale industries can not own individual wastewater treatment facility due to non-availability of land and skilled manpower for operation and maintenance of wastewater treatment plants. A centralized wastewater treatment facility for clusters of small scale industries is appropriate. This concept is gaining popularity in recent years. In India, various textile process operations are undertaken by individual small scale units. The wastewater generated at these units is conveyed to a common effluent treatment facility comprising of equalization, flocculation-clarification, activated sludge process, secondary clarification and finally discharge into inland surface water bodies. The wastewater from small scale cotton textile processing units was highly coloured and alkaline with average BOD and COD concentration of 205 and 790 mg l(-1), respectively. Due to the presence of several dyes, particularly reactive dyes, the biological treatment is often found less effective. Therefore, applicability of various physico-chemical treatment methods needs to be investigated in pursuit of an alternative to biological treatment of textile wastewater. A physico-chemical treatment scheme, involving chemical coagulation-sedimentation, dual media filtration, activated carbon adsorption followed by chemical oxidation was investigated in this paper. The quality of final treated wastewater in terms of BOD and COD was 18-24 and 230-240 mg l(-1), respectively through this scheme. A scheme of treatment comprising coagulation-sedimentation, dual media filtration, activated carbon, chemical oxidation may be considered as an alternative to biological treatment of textile wastewater. PMID:15881028

Pathe, P P; Biswas, A K; Rao, N N; Kaul, S N

2005-03-01

298

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

CERN Document Server

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

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

2008-01-01

299

"It's Really Making a Difference": How Small-Scale Research Projects Can Enhance Teaching and Learning  

Science.gov (United States)

Following an internal evaluation exercise, using Action Research, this paper identifies the positive impact of small-scale research projects on teaching and learning at a single case study UK University. Clear evidence is given of how the projects benefited students and staff, and enhanced institutional culture. Barriers to better practice are…

Dexter, Barbara; Seden, Roy

2012-01-01

300

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

DEFF Research Database (Denmark)

Thirty-nine untrained subjects made small- and full-scale evaluations of the acceptability of the quality of air at 22 deg.C and 40% RH, polluted by either carpet, felt floor covering, painted gypsum board, linoleum or chipboard. Small-scale evaluations were made on the air extracted from 200-L glass chambers ventilated at an airflow of 0.9 L/s. Full-scale assessments were made immediately upon entering offices ventilated at an outdoor air supply rate of 1.9 h-1. The ratio of ventilation rate to surface area of a building material was identical in the chambers and in the offices. Full-scale sensory ratings of acceptability of air polluted by carpet and by linoleum were systematically better than small-scale assessments, but not for the other three materials. Calculated sensory emission rates from carpet and linoleum were significantly lower in full scale than in small scale. When modelling the perceived air quality in spaces, sensory emission rates estimated in small scale may require a correction, probably depending on the nature of the chemicals emitted by a building material.

Wargocki, Pawel; Lagercrantz, Love Per

2002-01-01

 
 
 
 
301

Investigation of Small Break Loss-of-Coolant Phenomena in a Small Scale Nonnuclear Test Facility.  

Science.gov (United States)

A small-scale nonnuclear integral test facility designed to simulate a pressurized water reactor (PWR) system was used to evaluate the effects of a small break loss-of-coolant accident (LOCA) on the system thermal-hydraulic response. The experiment approx...

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

1980-01-01

302

Spelt - a pilot crop to strengthen co-operation between farmers, food processors, distributors and consumers  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In the beginning of the 1990's, spelt cultivation in Finland was rather unknown. First cultivation experiments at the organic research farm of MTT/Agricultural Engineering Research (Vakola) were done in co-operation with some farmers since 1993. Many farmers showed interest in cultivating spelt because of curiosity about crops suitable for organic farming, competition leadership by marketing new niche products, and consumers demand for healthy and high quality food produced pro-environmentall...

Scha?fer, Winfried

2001-01-01

303

The Small-Scale Dynamo and Non-Ideal MHD in Primordial Star Formation  

CERN Document Server

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

Schober, Jennifer; Federrath, Christoph; Glover, Simon; Klessen, Ralf; Banerjee, Robi

2012-01-01

304

Constraints on small-scale cosmological perturbations from gamma-ray searches for dark matter  

International Nuclear Information System (INIS)

Events like inflation or phase transitions can produce large density perturbations on very small scales in the early Universe. Probes of small scales are therefore useful for e.g. discriminating between inflationary models. Until recently, the only such constraint came from non-observation of primordial black holes (PBHs), associated with the largest perturbations. Moderate-amplitude perturbations can collapse shortly after matter-radiation equality to form ultracompact minihalos (UCMHs) of dark matter, in far greater abundance than PBHs. If dark matter self-annihilates, UCMHs become excellent targets for indirect detection. Here we discuss the gamma-ray fluxes expected from UCMHs, the prospects of observing them with gamma-ray telescopes, and limits upon the primordial power spectrum derived from their non-observation by the Fermi Large Area Space Telescope.

305

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

306

Constraints on small-scale cosmological perturbations from gamma-ray searches for dark matter  

CERN Document Server

Events like inflation or phase transitions can produce large density perturbations on very small scales in the early Universe. Probes of small scales are therefore useful for e.g. discriminating between inflationary models. Until recently, the only such constraint came from non-observation of primordial black holes (PBHs), associated with the largest perturbations. Moderate-amplitude perturbations can collapse shortly after matter-radiation equality to form ultracompact minihalos (UCMHs) of dark matter, in far greater abundance than PBHs. If dark matter self-annihilates, UCMHs become excellent targets for indirect detection. Here we discuss the gamma-ray fluxes expected from UCMHs, the prospects of observing them with gamma-ray telescopes, and limits upon the primordial power spectrum derived from their non-observation by the Fermi Large Area Space Telescope.

Scott, Pat; Akrami, Yashar

2012-01-01

307

Energy transfers and magnetic energy growth in small-scale dynamo  

CERN Document Server

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

Kumar, Rohit; Samtaney, Ravi

2013-01-01

308

Mesogranulation and small-scale dynamo action in the quiet Sun  

CERN Document Server

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 ...

Bushby, Paul J

2014-01-01

309

Prevalence of Small-scale Jets from the Networks of the Solar Transition Region and Chromosphere  

CERN Document Server

As the interface between the Sun's photosphere and corona, the chromosphere and transition region play a key role in the formation and acceleration of the solar wind. Observations from the Interface Region Imaging Spectrograph reveal the prevalence of intermittent small-scale jets with speeds of 80-250 km/s from the narrow bright network lanes of this interface region. These jets have lifetimes of 20-80 seconds and widths of 300 km or less. They originate from small-scale bright regions, often preceded by footpoint brightenings and accompanied by transverse waves with ~20 km/s amplitudes. Many jets reach temperatures of at least ~100000 K and constitute an important element of the transition region structures. They are likely an intermittent but persistent source of mass and energy for the solar wind.

Tian, H; Cranmer, S R; De Pontieu, B; Peter, H; Martínez-Sykora, J; Golub, L; McKillop, S; Reeves, K K; Miralles, M P; McCauley, P; Saar, S; Testa, P; Weber, M; Murphy, N; Lemen, J; Title, A; Boerner, P; Hurlburt, N; Tarbell, T D; Wuelser, J P; Kleint, L; Kankelborg, C; Jaeggli, S; Carlsson, M; Hansteen, V; McIntosh, S W

2014-01-01

310

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english Large scale magnetic fields in galaxies are thought to be generated, by a mean field dynamo. In order to have generated the fields observed, the dynamo would have had to have operated for a sufficiently long period of time. However, magnetic fields of similar intensities to the one in our galaxy, 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

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

1651-16-01

311

Dynamics of small-scale Alfven waves in the magnetosphere resonator  

International Nuclear Information System (INIS)

Mathematical formalism to describe transverse small-scale dispersion Alfven waves in heterogeneous plasma and curvilinear magnetic field of magnetosphere has been developed. In the formalism it is possible to separate the description of longitudinal and transverse structure of the field. In the longitudinal direction the perturbation presents a standing wave. For the transverse structure a monomeric equation is obtained, coefficients of which are determined as average ones along the force line of magnetosphere parameters. The equation permits to provide a complete picture of transverse propagation of small-scale Alfven waves in magnetosphere. Existence of a closed resonator for such waves in the internal plasmasphere and the presence of transition layer of magnetic shells near plasmapause, which absorbs completely incident Alfven waves, are of special interest. The energy dissipated in the layer results in the known phenomenon of red arc

312

Small-scale piezoelectric energy harvesting devices using low-energy-density sources  

International Nuclear Information System (INIS)

Over the last decade, small-scale energy harvesting devices that can power household electronic systems have experienced rapid development in both the research and the industrial fields. However, the large majority of work done in this domain still focuses on high-energy-density sources, which are not always available in the vicinity of the device. In that case, it is, therefore, important to use other sources, which, nevertheless, present lower energy densities. Hence, the purpose of this paper is to investigate such harvesting methods, highlighting their differences with classical techniques that rely on high-density energy resources. Additionally, the present study also aims at reviewing existing techniques for small-scale energy harvesting using piezoelectric devices, as well as presenting new designs when dealing with low energy density sources, with a particular focus on wind and rain.

313

Small-scale piezoelectric energy harvesting devices using low-energy-density sources  

Energy Technology Data Exchange (ETDEWEB)

Over the last decade, small-scale energy harvesting devices that can power household electronic systems have experienced rapid development in both the research and the industrial fields. However, the large majority of work done in this domain still focuses on high-energy-density sources, which are not always available in the vicinity of the device. In that case, it is, therefore, important to use other sources, which, nevertheless, present lower energy densities. Hence, the purpose of this paper is to investigate such harvesting methods, highlighting their differences with classical techniques that rely on high-density energy resources. Additionally, the present study also aims at reviewing existing techniques for small-scale energy harvesting using piezoelectric devices, as well as presenting new designs when dealing with low energy density sources, with a particular focus on wind and rain.

Lallart, Mickael; Priya, Shashank; Bressers, Scott; Inman, Daniel [Virginia Tech, Blacksburg, Virginia (United States)

2010-10-15

314

Thermal Control Characteristics in a Small Scale Hydrogen Isotope Storage Bed  

Energy Technology Data Exchange (ETDEWEB)

Hydrogen isotope gases needed for the daily operation of the tokamak of nuclear fusion plants are safely stored in and supplied from beds. Metal tritides are currently proposed for the safe and high density storage and delivery of tritium gas during the operation of fusion machines. Different metal tritides show various storage and delivery properties. Among the many metal tritides, uranium and zirconium cobalt have been suggested as two of the most applicable tritium storage materials. A small-scale bed was fabricated to compare the properties of tritium recovery and the delivery of materials. It should be equipped with a heat control. Thus, in this study, we have performed thermal control tests (heating, cooling, and thermal insulation) of the small-scale bed

Chung, Dong You; Lee, Jung Min; Koo, Dae Seo; Chung, Hong Suk [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2012-05-15

315

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

Science.gov (United States)

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

Mei, Yinzhen

2011-10-01

316

STRATEGIC PLANNING IN BRAZILIAN SMALL-SCALE MUNICIPALITIES: IS THE BALANCED SCORECARD A FEASIBLE TOOL?  

Directory of Open Access Journals (Sweden)

Full Text Available Balanced Scorecard has not yet been tested in Brazilian small-scale municipalities. The BSC is based on dimensions of Learning and Growth, Internal Processes Business, Financial and Customer. In order to fit to public organizations it needs some adjustments due to these organizations’ objectives. This paper presents a case study focusing on municipalities from Brazil. Data has been collected by action research and analysed by qualitative analysis. The analysis indicates that the BSC can be successfully implemented in small-scale municipalities. It soundly depends on Mayor’s leadership and staff’s engagement. The way the intervention is conducted is also important. By keeping it as easier as possible, employees are more able to participate and to collaborate in the process.

Ricardo Corrêa Gomes

2014-03-01

317

Prevalence of small-scale jets from the networks of the solar transition region and chromosphere.  

Science.gov (United States)

As the interface between the Sun's photosphere and corona, the chromosphere and transition region play a key role in the formation and acceleration of the solar wind. Observations from the Interface Region Imaging Spectrograph reveal the prevalence of intermittent small-scale jets with speeds of 80 to 250 kilometers per second from the narrow bright network lanes of this interface region. These jets have lifetimes of 20 to 80 seconds and widths of ?300 kilometers. They originate from small-scale bright regions, often preceded by footpoint brightenings and accompanied by transverse waves with amplitudes of ~20 kilometers per second. Many jets reach temperatures of at least ~10(5) kelvin and constitute an important element of the transition region structures. They are likely an intermittent but persistent source of mass and energy for the solar wind. PMID:25324395

Tian, H; DeLuca, E E; Cranmer, S R; De Pontieu, B; Peter, H; Martínez-Sykora, J; Golub, L; McKillop, S; Reeves, K K; Miralles, M P; McCauley, P; Saar, S; Testa, P; Weber, M; Murphy, N; Lemen, J; Title, A; Boerner, P; Hurlburt, N; Tarbell, T D; Wuelser, J P; Kleint, L; Kankelborg, C; Jaeggli, S; Carlsson, M; Hansteen, V; McIntosh, S W

2014-10-17

318

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

Energy Technology Data Exchange (ETDEWEB)

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.

None,

1980-05-01

319

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

Directory of Open Access Journals (Sweden)

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.

Dilip Jagdale

2014-08-01

320

Magnetic Field Tunable Small-scale Mechanical Properties of Nickel Single Crystals Measured by Nanoindentation Technique  

Science.gov (United States)

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.

Zhou, Hao; Pei, Yongmao; Fang, Daining

2014-04-01

 
 
 
 
321

Thermal Control Characteristics in a Small Scale Hydrogen Isotope Storage Bed  

International Nuclear Information System (INIS)

Hydrogen isotope gases needed for the daily operation of the tokamak of nuclear fusion plants are safely stored in and supplied from beds. Metal tritides are currently proposed for the safe and high density storage and delivery of tritium gas during the operation of fusion machines. Different metal tritides show various storage and delivery properties. Among the many metal tritides, uranium and zirconium cobalt have been suggested as two of the most applicable tritium storage materials. A small-scale bed was fabricated to compare the properties of tritium recovery and the delivery of materials. It should be equipped with a heat control. Thus, in this study, we have performed thermal control tests (heating, cooling, and thermal insulation) of the small-scale bed

322

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

Science.gov (United States)

Public opinion concerning social welfare is largely driven by perceptions of recipient deservingness. Extant research has argued that this heuristic is learned from a variety of cultural, institutional, and ideological sources. The present article provides evidence supporting a different view: that the deservingness heuristic is rooted in psychological categories that evolved over the course of human evolution to regulate small-scale exchanges of help. To test predictions made on the basis of this view, a method designed to measure social categorization is embedded in nationally representative surveys conducted in different countries. Across the national- and individual-level differences that extant research has used to explain the heuristic, people categorize welfare recipients on the basis of whether they are lazy or unlucky. This mode of categorization furthermore induces people to think about large-scale welfare politics as its presumed ancestral equivalent: small-scale help giving. The general implications for research on heuristics are discussed. PMID:22375300

Petersen, Michael Bang

2012-01-01

323

A Search for Small-Scale Anisotropy of PeV Cosmic Rays  

CERN Document Server

Recent results of Milagro, Tibet, ARGO-YBJ and IceCube experiments on the small-scale anisotropy of Galactic cosmic rays (CRs) with energies from units up to a few hundred TeV arise a question on a possible nature of the observed phenomenon, as well as on the anisotropy of CRs at higher energies. An analysis of a small-scale anisotropy of CRs with energies at around PeV registered with the EAS MSU array presented in the article, reveals a number of regions with an excessive flux. A typical size of the regions varies from 3 up to 12 degrees. We study correlation of these regions with positions of potential astrophysical sources of CRs and discuss a possible origin of the observed anisotropy.

Zotov, M Yu

2012-01-01

324

Some tests on small-scale rectangular throat ejector. [thrust augmentation for V/STOL aircraft  

Science.gov (United States)

A small scale rectangular throat ejector with plane slot nozzles and a fixed throat area was tested to determine the effects of diffuser sidewall length, diffuser area ratio, and sidewall nozzle position on thrust and mass augmentation. The thrust augmentation ratio varied from approximately 0.9 to 1.1. Although the ejector did not have good thrust augmentation performance, the effects of the parameters studied are believed to indicate probable trends in thrust augmenting ejectors.

Dean, W. N., Jr.; Franke, M. E.

1979-01-01

325

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

International Nuclear Information System (INIS)

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

326

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

Energy Technology Data Exchange (ETDEWEB)

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

NONE

1996-03-01

327

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

Energy Technology Data Exchange (ETDEWEB)

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

Smith, G.L.

1996-03-01

328

Small scale model for experimental investigations of the dynamic behavior of spherical steel containments  

International Nuclear Information System (INIS)

In order to study the influence of imperfections on the earthquake response of spherical steel containments corresponding theoretical and experimental investigations were started. The experimental investigations will be performed with a small scale model with a diameter of 1.3 m and a wall thickness of about 1 mm. The necessary high precision of the spherical model required a complicated manufacturing process. The steps of this process and the resulting tolerances of the model are discussed in this paper

329

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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. Quanti...

Atanga, Ngufor L.; Treydte, Anna C.; Regina Birner

2013-01-01

330

Environmental changes, agricultural crisis and small-scale fishing development in the Casamance region, Senegal  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Cormier Salem, Marie-christine

1994-01-01

331

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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”...

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

332

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

Directory of Open Access Journals (Sweden)

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

Igor Ani?

2011-04-01

333

A Genealogy of Governing Economic Behaviour : Small-scale credit in Malawi 1930–2010  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this thesis the aim has been to analyse changes and continuity in the governing of economic behaviour in small-scale credit schemes in colonial Nyasaland and independent Malawi from 1930 until 2010. Furthermore, how the effects of history in terms of how colonial and post-colonial development discourses and practices have been rephrased and reused in the early 21st century are discussed. The study focuses on the teaching and fostering of borrowers’ economic behaviour in order to reach in...

Va?rlander, Johanna

2013-01-01

334

STUDY AND VALIDATION OF BODY POSTURES OF WORKERS WORKING IN SMALL SCALE INDUSTRY THROUGH RULA  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Ergonomics is an important aspect in order to improve workers performance at work, develop an autonomous rhythm at work which will synchronize physical, physiological and psychological aspectsthat is responsible for human behavior and efficiency at work and stands as a key factor deciding workers effectiveness. This paper focuses the attention on the ergonomics consideration required to begoverned in the small scale industries, a specific case of tractor trolley manufacturing unit is consider...

Agrawal, D. N.; Jibhakate, M. S.; Madankar, T. A.

2011-01-01

335

Small-scale plasma irregularities produced during electron attachment chemical releases  

Science.gov (United States)

In situ measurements of small-scale plasma density irregularities made during sounding rocket experiments that released electron attachment materials into the ionosphere are presented. A 2D electrostatic simulation model that includes attachment chemistry is used to study the source and evolution of these irregularities. The simulation shows (1) that large electron flow velocity shears develop on the boundary of the electron depletion and (2) these shears drive a plasma instability that is the likely source of the irregularities.

Scales, W. A.; Bernhardt, P. A.; Ganguli, G.; Siefring, C. L.; Rodriguez, P.

1994-01-01

336

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

337

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

338

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

CERN Document Server

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

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

1999-01-01

339

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

Science.gov (United States)

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

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

1998-05-01

340

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

Science.gov (United States)

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 simeq 10-11 Gauss by cosmic microwave background observations.

Jedamzik, Karsten; Abel, Tom

2013-10-01

 
 
 
 
341

Effect of heat treatment on small scale fragmentation of aluminium alloy  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Small scale explosions, using a detonator, of 7075 aluminium alloy cylinders, 15-100 mm outside diameter, were carried out to investigate the effects of heat treatment on fragmentation. This was the finest for the strongest as received alloy and coarsest for the softest overaged alloy. This effect was similar to that seen in investigations of the fragmentation of steel. Cylinders of 50 and 100 mm in diameter did not fragment but plastically deformed with maximum deformation ...

Edwards, M. R.; Deal, C.

2011-01-01

342

The Impact of Small-Scale Topography on the Dynamical Balance of the Ocean  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The impact of small-scale topography on the ocean’s dynamical balance is investigated by quantifying the rates at which internal wave drag extracts (angular) momentum and vorticity from the general circulation. The calculation exploits the recent advent of two near-global descriptions of topographic roughness on horizontal scales on the order of 1–10 km, which play a central role in the generation of internal lee waves by geostrophic flows impinging on topography and have been hitherto un...

Naveira Garabato, Alberto C.; Nurser, A. J. George; Scott, Robert B.; Goff, John A.

2013-01-01

343

A small-scale experimental reactor combined with a simulator for training purposes  

International Nuclear Information System (INIS)

The authors discuss how a small-scale reactor combined to a training simulator can be a valuable aid in all forms of training. They describe the CEN-based SILOETTE reactor in Grenoble and its combined simulator. They also take a look at prospects for the future of the system in the light of experience acquired with the ARIANE reactor and the trends for the development of simulators for training purposes

344

Proceedings of a Topical Meeting On Small Scale Geothermal Power Plants and Geothermal Power Plant Projects  

Energy Technology Data Exchange (ETDEWEB)

These proceedings describe the workshop of the Topical Meeting on Small Scale Geothermal Power Plants and Geothermal Power Plant Projects. The projects covered include binary power plants, rotary separator, screw expander power plants, modular wellhead power plants, inflow turbines, and the EPRI hybrid power system. Active projects versus geothermal power projects were described. In addition, a simple approach to estimating effects of fluid deliverability on geothermal power cost is described starting on page 119. (DJE-2005)

None

1986-02-12

345

Circular periodic motion of plasma produced by a small-scale vacuum arc  

Science.gov (United States)

A small-scale plasma source based on a low-current vacuum arc is described. Temporal and spatial evolution of the ion current is measured. The plasma plume circular motion follows the cathode spot motion in the retrograde direction and is guided along the magnetic field line. It is observed that the applied magnetic field efficiently guide the plasma leading to an increase in the output ion current by a factor of 50 in comparison with that without the magnetic field.

Zhuang, T.; Shashurin, A.; Keidar, M.; Beilis, I. I.

2011-02-01

346

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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

Peterson, J. B.; 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

347

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)

348

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

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

2014-01-01

349

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)

350

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Fe?doroff, Eric; Ponge, Jean-franc?ois; Dubs, Florence; Ferna?ndez-gonza?lez, Federico; Lavelle, Patrick

2005-01-01

351

On the ultraviolet signatures of small scale heating in coronal loops  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Parenti, Susanna; Young, Peter R.

2010-01-01

352

Some comparisons between small-scale pool swell experiments and model predictions  

International Nuclear Information System (INIS)

Predictions from a one-dimensional pool swell model are compared with results from small-scale pool swell tests. The main elements of the model other than the geometric simplification are identical to the assumptions that underlie the hydrodynamic scaling laws investigated in the pool swell experiments. An experimental record of air bubble growth history is compared with the predictions from an axisymmetric pool swell code calculation. 10 refs

353

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

The diversity of small-scale irrigation in the Ethiopian Blue Nile basin comprises small dams, wells, ponds and river diversion. The diversity of irrigation infrastructure is partly a consequence of the topographic heterogeneity of the Fogera plains. Despite similar social-political conditions and the same administrative framework, irrigation facilities are built, used and managed differently, ranging from informal arrangements of households and 'water fathers' to water user associations, as ...

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

2012-01-01

354

The way to self-sufficiency : An interview study about small scale business and integration  

Digital Repository Infrastructure Vision for European Research (DRIVER)

With a starting point in a project for reinforcing small scale business among immigrants in Sweden, carried out within Swedish for immigrants (sfi), the aim for this thesis is to examine the project from the view and experiences of the participants. Interviews with participants in the project have been inspired by the teoretical and methodological views of Grounded Theory. The interviews show that some participants want to start their own business, but almost as many don’t have that dream. ...

Andersson, Josefin

2009-01-01

355

a MRC Method for Low Methane Sources in Small Scale Cmm Liquefaction Plant  

Science.gov (United States)

Coalmine methane (CMM) liquefiers in small scale, 5000 to 20000 Nm3/d, are applied more and more in Chinese LNG projects. Most CMM sources contain ˜50% methane and 50% air. In order to make use of these low methane energy sources, a new full-scale separation system was designed and tested using a mixed refrigerant cycle. A method of removing air from CMM sources with a liquefying process is discussed in this paper.

Li, H. Y.; Jia, L. X.; Yin, Q. S.; Fan, Q. H.; Yang, G. D.; Liu, X. K.; Bai, W.; Xu, F. Y.; Ji, Z. M.; Cui, J. S.

2008-03-01

356

Design of Saving Circuit with Fuzzy Logic Control for Residences and Small Scale Enterprises  

Digital Repository Infrastructure Vision for European Research (DRIVER)

One of the most effective methods of achieving savings in electrically-operated systems and increasing the efficiency is reactive power compensation. With the presently enforced regulation, compensation is mandatory for industrial consumers and it is done at certain power intervals, there is no regulation for residences and small scale enterprises on this subject. In this study, measurement of the reactive power in single-phase systems has been developed, as well as calculation for directi...

Basciftci, F.; Hatay, O. F.

2010-01-01

357

Cogeneration with an ORC application in a small-scale existing district heating system  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A part of reducing the increased greenhouse effect is to reduce emissions of carbon dioxide.Much of the carbon dioxide emitted by the energy sector comes from electricity produced incondensing power plants. These emissions can be reduced by the development ofcogeneration, i.e. simultaneous production of heat and electricity. One way to do this is tocomplement the existing, small-scale heat plants with electricity production via a productionintegrated ORC (Organic Rankine Cycle). The purpose o...

Karlsson, Andreas

2010-01-01

358

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

Oyetunji, A.

2010-01-01

359

Linking birds, fields and farmers.  

Science.gov (United States)

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

Swagemakers, Paul; Wiskerke, Han; Van Der Ploeg, Jan Douwe

2009-05-01

360

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

Directory of Open Access Journals (Sweden)

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

Justice G. Djokoto

2012-02-01

 
 
 
 
361

Magnetic field amplification by the small-scale dynamo in the early Universe  

Science.gov (United States)

In this paper we show that the Universe is already strongly magnetized at very early epochs during cosmic evolution. Our calculations are based on the efficient amplification of weak magnetic seed fields, which are unavoidably present in the early Universe, by the turbulent small-scale dynamo. We identify two mechanisms for the generation of turbulence in the radiation dominated epoch where velocity fluctuations are produced by the primordial density perturbation and by possible first-order phase transitions at the electroweak or QCD scales. We show that all the necessities for the small-scale dynamo to work are fulfilled. Hence, this mechanism, operating due to primordial density perturbations, guarantees fields with comoving field strength B0˜10-6?1/2 nG on scales up to ?c˜0.1 pc, where ? is the saturation efficiency. The amplification of magnetic seed fields could be even larger if there are first-order phase transitions in the early Universe. Where, on scales up to ?c˜100 pc, the comoving field strength due to this mechanism will be B0˜10-3?1/2 nG at the present time. Such fields, albeit on small scales, can play an important role in structure formation and could provide an explanation to the apparently observed magnetic fields in the voids of the large-scale structure.

Wagstaff, Jacques M.; Banerjee, Robi; Schleicher, Dominik; Sigl, Günter

2014-05-01

362

Very small scale clustering of quasars from a complete quasar lens survey  

Science.gov (United States)

We measure the small-scale (comoving separation ?) two-point correlation function of quasars using a sample of 26 spectroscopically confirmed binary quasars at 0.6 SQLS). Thanks to careful candidate selections and extensive follow-up observations of the SQLS, which are aimed at constructing a complete quasar lens sample, our sample of binary quasars is also expected to be nearly complete within a specified range of angular separations and redshifts. The measured small-scale correlation function rises steeply towards smaller scales, which is consistent with earlier studies based on incomplete or smaller binary quasar samples. We find that the quasar correlation function can be fitted by a power law reasonably well over 4 orders of magnitude, with the best-fitting slope of ?(r) ? r-1.92. We interpret the measured correlation function within the framework of the halo occupation distribution (HOD). We propose a simple model that assumes a constant fraction of quasars that appear as satellites in dark matter haloes, and find that measured small-scale clustering signals constrain the satellite fraction to fsat=0.054+0.017-0.016 for a singular isothermal sphere number density profile of satellites. We note that the HOD modelling appears to underpredict clustering signals at the smallest separations of rp˜ 10 h-1 kpc unless we assume very steep number density profiles (such as a Navarro-Frenk-White profile with the concentration parameter cvir?30), which may be suggestive of enhanced quasar activities by direct interactions.

Kayo, Issha; Oguri, Masamune

2012-08-01

363

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

DEFF Research Database (Denmark)

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

Roesen, Hanne Ravn; Thomassen, Kristina

2010-01-01

364

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

Energy Technology Data Exchange (ETDEWEB)

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

Balk, Thomas

2012-07-27

365

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

CERN Document Server

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

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

2004-01-01

366

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

Energy Technology Data Exchange (ETDEWEB)

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 SO{sub 3} decomposer, which generates the process gas such as H{sub 2}O, O{sub 2}, SO{sub 2}, and SO{sub 3} 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

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

2012-05-15

367

The Opacity of the Intergalactic Medium During Reionization: Resolving Small-Scale Structure  

CERN Document Server

Early in the reionization process, the intergalactic medium (IGM) would have been quite inhomogeneous on small scales, due to the low Jeans mass in the neutral IGM and the hierarchical growth of structure in a cold dark matter Universe. This small-scale structure acted as an important sink during the epoch of reionization, impeding the progress of the ionization fronts that swept out from the first sources of ionizing radiation. Here we present results of high-resolution cosmological hydrodynamics simulations that resolve the cosmological Jeans mass of the neutral IGM in representative volumes several Mpc across. The adiabatic hydrodynamics we follow are appropriate in an unheated IGM, before the gas has had a chance to respond to the photoionization heating. Our focus is determination of the resolution required in cosmological simulations in order to sufficiently sample and resolve small-scale structure regulating the opacity of an unheated IGM. We find that a dark matter particle mass of m_dm 1 Mpc are req...

Emberson, J D; Alvarez, Marcelo A

2013-01-01

368

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.

369

Center-to-Limb Variations of Small-Scale Magnetic Features  

Science.gov (United States)

During August/September 1999, we observed continuum images in the visible (520 nm) and infrared (1600 nm) of various active regions during their limb-to-limb passage. The images were obtained with the 65 cm vacuum reflector of the Big Bear Solar Observatory and speckle masking has been applied to obtain almost diffraction limited images of small-scale magnetic features such as pores, magnetic knots, and faculae. The infrared images were taken with a new 320 x 240 pixel, 12-bit, 30 fps InGaAs CCD camera. The continuum images are complemented by videomagnetograms obtained at Ca I (610.3 nm) with the 25 cm vacuum refractor. We present the first results of a comprehensive study on the relationship of magnetic field strength and continuum contrast of small-scale magnetic features as a function of disk position. The underlying mechanism of small-scale flux tubes is of particular importance for solar irradiance variations over the 11 year solar activity cycle.

Denker, C.; Spirock, T. J.; Wang, H.; Goode, P. R.

2000-05-01

370

Running with BICEP2: implications for small-scale problems in CDM  

Science.gov (United States)

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.

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

2014-10-01

371

Features and Distribution of Intense, Small Scaled Field Aligned Currents in Polar Regions  

Science.gov (United States)

Field-aligned currents (FACs) can be observed over a wide range of scales. Generally, the current density is getting higher the smaller the scales are. The low-Earth orbiting satellite CHAMP allows accessing FAC down to scales of a couple of 100m based on its magnetic field vector data sampled at 50 Hz. There are occasional bursts of small-scale FACs having amplitudes about two decades above the large-scaled ones (100-300km). These events are clustering in the dayside auroral region. Using CHAMP magnetic field vector data of four years (2001 - 2005) detailed studies of these currents can be performed. High-resolution plots show that there seems to be smallest scale size of about 1km. Upward and downward FACs are balanced very well locally. The large number of events allows to study the statistical properties. Bursts of FAC are isolated to individual events and the occurrence rate in Magnetic local time and latitude is investigated. Small scaled FAC seems to be associated with electron temperature enhancements in the vicinity of the polar cusp region. The relation between small-scale FACs, electron temperature and plasma density is studied in a superposed epoch analysis.

Rother, M.; Lühr, H.

2006-05-01

372

Coronal hole boundaries evolution at small scales: I. EIT 195 A and TRACE 171 A view  

CERN Document Server

We aim at studying the small-scale evolution at the boundaries of an equatorial coronal hole connected with a channel of open magnetic flux with the polar region and an `isolated' one in the extreme-ultraviolet spectral range. We intend to determine the spatial and temporal scale of these changes. Imager data from TRACE in the Fe IX/X 171 A passband and EIT on-board Solar and Heliospheric Observatory in the Fe XII 195 A passband were analysed. We found that small-scale loops known as bright points play an essential role in coronal holes boundaries evolution at small scales. Their emergence and disappearance continuously expand or contract coronal holes. The changes appear to be random on a time scale comparable with the lifetime of the loops seen at these temperatures. No signature was found for a major energy release during the evolution of the loops. Although coronal holes seem to maintain their general shape during a few solar rotations, a closer look at their day-by-day and even hour-by-hour evolution dem...

Madjarska, M S

2009-01-01

373

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

374

Simulations of Small-Scale Electric Potential Structures in the Inner Magnetosphere During Storms  

Science.gov (United States)

The relationship between the partial ring current pressure peak and the electric potential structure is examined. The hot ion pressure tries to limits itself through the electric field associated with the ionospheric closure currents. To investigate this negative feedback of the stormtime ring current, simulation results for several magnetic storms are analyzed and then compared against IMAGE HENA data for a variety of energy channels. In addition, several set-up configurations of the kinetic ring current model are used to assess the influence of the numerical approach. It is found that the small-scale well-and-peak potential pairs, formed when magnetotail plasma is injected or convected in to the inner magnetosphere, significantly change the near-Earth plasma distribution. The main pressure peak is broken into smaller peaks and the flow pattern of the hot ions is altered. One consequence of this is that the pressure peak remains on the nightside rather than shifting towards dusk. Other effects include the creation of subauroral polarization streams and injection flow channels in the potential distributions at various times during the storm, formed when the small-scale electric field is locally aligned with the large-scale electric field. The small-scale structures are not particularly visible in the energetic neutral atom images, but the location of the simulated pressure peak is often closer to the observed location when this effect is included.

Liemohn, M. W.; Ridley, A. J.; Kozyra, J. U.; Brandt, P. C.

2007-05-01

375

Responding to Globalization: Impacts of Certification on Colombian Small-Scale Coffee Growers  

Directory of Open Access Journals (Sweden)

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.

Ximena Rueda

2013-09-01

376

Determining erosion relevant soil characteristics with a small-scale rainfall simulator  

Science.gov (United States)

The use of soil erosion models is of great importance in soil and water conservation. Routine application of these models on the regional scale is not at least limited by the high parameter demands. Although the EROSION 3D simulation model is operating with a comparable low number of parameters, some of the model input variables could only be determined by rainfall simulation experiments. The existing data base of EROSION 3D was created in the mid 90s based on large-scale rainfall simulation experiments on 22x2m sized experimental plots. Up to now this data base does not cover all soil and field conditions adequately. Therefore a new campaign of experiments would be essential to produce additional information especially with respect to the effects of new soil management practices (e.g. long time conservation tillage, non tillage). The rainfall simulator used in the actual campaign consists of 30 identic modules, which are equipped with oscillating rainfall nozzles. Veejet 80/100 (Spraying Systems Co., Wheaton, IL) are used in order to ensure best possible comparability to natural rainfalls with respect to raindrop size distribution and momentum transfer. Central objectives of the small-scale rainfall simulator are - effectively application - provision of comparable results to large-scale rainfall simulation experiments. A crucial problem in using the small scale simulator is the restriction on rather small volume rates of surface runoff. Under this conditions soil detachment is governed by raindrop impact. Thus impact of surface runoff on particle detachment cannot be reproduced adequately by a small-scale rainfall simulator With this problem in mind this paper presents an enhanced small-scale simulator which allows a virtual multiplication of the plot length by feeding additional sediment loaded water to the plot from upstream. Thus is possible to overcome the plot length limited to 3m while reproducing nearly similar flow conditions as in rainfall experiments on standard plots. The simulator is extensively applied to plots of different soil types, crop types and management systems. The comparison with existing data sets obtained by large-scale rainfall simulations show that results can adequately be reproduced by the applied combination of small-scale rainfall simulator and sediment loaded water influx.

Schindewolf, M.; Schmidt, J.

2009-04-01

377

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

Directory of Open Access Journals (Sweden)

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

M.A. Oladoja

2007-01-01

378

Education Needs of Michigan Farmers  

Science.gov (United States)

In 2008 MSU Extension evaluated their program to identify the major areas of educational need for Michigan farmers and agribusiness operators. Surveys were mailed to a stratified random sample from Michigan Agricultural Statistics Service records of dairy, livestock, swine, cash crops, fruit, vegetable, and nursery/greenhouse producers. Findings…

Suvedi, Murari; Jeong, Eunseong; Coombs, John

2010-01-01

379

Entrepreneurship of Dutch dairy farmers  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Keywords: Dairy farming, farm size, Theory of Planned Behaviour, goals, attitudes, entrepreneur entrepreneurship, competencies, psychological characteristics, agriculture, entrepreneur, dairy farms, entrepreneurial success, job satisfaction, training programme.Several developments in theNetherlandsas well as in the other countries within the EU are forcing dairy farmers to reconsider their in...

Bergevoet, R. H. M.

2005-01-01

380

Land acquisitions and foreign direct investment - challenges and opportunities for developing countries : case study of Kisarawe District, Tanzania; focusing small scale farmers  

Digital Repository Infrastructure Vision for European Research (DRIVER)

International investors have recently shown a fast growing interest in large scale acquisitions of farmlands in developing countries. Lands, which only a short time ago seemed outside of interest are now being sought by international investors. Concern of food security, high food and oil prices, and scope of alternative energy to produce agrofuels are seen as primary push factors in this fast-evolving context. Foreign investors are typically large, wealthy transnational firms or rich governme...

Hamal, Bishwash

2011-01-01

 
 
 
 
381

Mechanisms of Obtaining Membership of Farmer Collectives  

Directory of Open Access Journals (Sweden)

Full Text Available This paper puts forward the corresponding solutions and suggestions through analyzing mechanisms of obtaining membership of farmer collectives in the normative sense, and aiming at the plight of obtaining farmer collective membership.

Debin HOU

2013-12-01

382

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

CERN Document Server

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

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

2012-01-01

383

Extension's Role with Farmers' Markets: Working with Farmers, Consumers, and Communities.  

Science.gov (United States)

Extension education can help farmers and consumers enjoy benefits of farmers' markets by helping farmers learn about marketing, assisting communities with site selection, encouraging use of Women Infants Children Farmers' Market Nutrition Program coupons, and teaching consumers about food use and preservation. (SK)

Abel, Jennifer; Thomson, Joan; Maretzki, Audrey

1999-01-01

384

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

Science.gov (United States)

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

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

2013-04-01

385

Measurement of the effects of large scale anisotropy on the small scales of turbulence  

Science.gov (United States)

This thesis reports measurements of anisotropy in a laboratory turbulent flow generated by two oscillating grids. It has recently been identified that SO(3) decomposition of Eulerian structure functions provides a powerful tool for analyzing anisotropy in turbulence. From 3D particle tracks obtained with stereoscpic high speed video, we measure the longitudinal Eulerian structure functions for which SO(3) decomposition becomes a spherical harmonic decomposition. This method allows us to measure the anisotropy in different sectors, specified by j and m of the spherical harmonics Yjm (theta, ?). In order to acquire huge data sets required for the full 3D measurement of anisotropy as a function of scale, we have upgraded the optical tracking system to four high speed cameras with a new real-time image compression system. We achieved compression ratios of 154--614 depending on the number of particles appearing in an image. Anisotropy measurements are performed at three different detection volumes in the tank for two grid frequencies where Reynolds numbers vary from Relambda = 132 to Relambda = 277. Increasing j sectors show faster decay of anisotropy as scale decreases, consistent with the idea that the small scales should become isotropic at very high Reynolds number. Measured anisotropic scaling exponents are also consistent with previous studies performed with numerical simulations and hot wire anemometry. By conditioning the different j sectors on the instantaneous large scale velocity, we are able to quantify the dependence of the anisotropy on the state of the large scales. The isotropic sector shows a strong dependence on the state of the large scales. For the isotropic sector, this strong dependence is the same at all length scales showing that the small scales do not become independent of the large scales and confirms previous work by Blum et al. However, for a given state of the large scales, the anisotropic sector diminishes toward smaller length scales, indicating that the small scales are becoming isotropic even though they are not becoming independent of the large scales.

Wijesinghe, Susantha W. A.

386

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

Energy Technology Data Exchange (ETDEWEB)

Potential environmental impacts in reservoirs and downstream river reaches below dams that may be caused by the water level fluctuation resulting from development and operation of small scale (under 25MW) hydroelectric projects are identified. The impacts discussed will be of potential concern at only those small-scale hydroelectric projects that are operated in a store and release (peaking) mode. Potential impacts on physical and chemical characteristics in reservoirs resulting from water level fluctuation include resuspension and redistribution of bank and bed sediment; leaching of soluble organic matter from sediment in the littoral zone; and changes in water quality resulting from changes in sediment and nutrient trap efficiency. Potential impacts on reservoir biota as a result of water level fluctuation include habitat destruction and the resulting partial or total loss of aquatic species; changes in habitat quality, which result in reduced standing crop and production of aquatic biota; and possible shifts in species diversity. The potential physical effects of water level fluctuation on downstream systems below dams are streambed and bank erosion and water quality problems related to resuspension and redistribution of these materials. Potential biological impacts of water level fluctuation on downstream systems below dams result from changes in current velocity, habitat reduction, and alteration in food supply. These alterations, either singly or in combination, can adversely affect aquatic populations below dams. The nature and potential significance of adverse impacts resulting from water level fluctuation are discussed. Recommendations for site-specific evaluation of water level fluctuation at small-scale hydroelectric projects are presented.

Hildebrand, S.G. (ed.)

1980-10-01

387

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

DEFF Research Database (Denmark)

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