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Factors Affecting the Choices of Coping Strategies for Climate Extremes: The Case of Yabello District, Borana Zone, Oromia National Regional State, Ethiopia
Dirriba Mengistu,
Jema Haji
Issue:
Volume 3, Issue 4, August 2015
Pages:
129-136
Received:
28 January 2015
Accepted:
10 February 2015
Published:
25 June 2015
Abstract: This study was undertaken in Yabello district of Borana zone to identify factors affecting the choices of coping strategies for climate extremes and the ongoing coping strategies in topical condition. The primary data collected from 123-sample households was analyzed with multinomial logit model. The multinomial logit outcomes were includes coping strategy 1 (Livestock diversification based coping strategies), coping strategy 2 (Integrated crop-livestock based diversification based coping strategies), coping strategy 3 (Livestock diversification, water and rangeland management based coping strategies) and coping strategy 4 (Livestock diversification, income earning opportunities and strategic feeding system based coping strategies). From MNLM result, sex of household head, education status of household head, size of livestock holding, market distance from homestead, access to credit, access to early warning information, access to training and pastoral/agro-pastoral income are the key determinants of the choices of coping strategies for climate extremes. Thus, establishment of formal early warning information centers and sophisticated delivery system, improving access to market, training, credit scheme, improving livestock holding and income of the household would boost the choices of best coping strategies to overcome deleterious impacts of climate extremes.
Abstract: This study was undertaken in Yabello district of Borana zone to identify factors affecting the choices of coping strategies for climate extremes and the ongoing coping strategies in topical condition. The primary data collected from 123-sample households was analyzed with multinomial logit model. The multinomial logit outcomes were includes coping ...
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Quartz Veins Characteristics and Au Mineralization Within the Batouri Au District, East Cameroon
Mero Yannah,
Cheo Emmanuel Suh,
Mboudou Germain M. Mboudou
Issue:
Volume 3, Issue 4, August 2015
Pages:
137-149
Received:
28 May 2015
Accepted:
12 June 2015
Published:
30 June 2015
Abstract: The Batouri south Au district of East Cameroon is hosted by biotite-amphibole meta-granites that belong to the Pan-African group of Pre-to Syn D1 and D2 Neoproterozoic granitoids. Hydrothermal activity and Au mineralization in this area is greatly enhanced by the presence of fractures, foliations, faults (sinistral) and vein splays hosted within a foliated meta-granite basement. Thirteen samples of 1.00 kg each of quartz vein were crushed and panned for Au-grain recovery. Fire Assay geochemistry was used to analyze eighteen samples for Au. Field results identified foliated and non-foliated GQV/BQV quartz vein varieties. The mineralization style in the area is mainly by fracture filled. Disseminated Au is common in the weathered wall rock envelop associated with mineralized veinlets. Au-grade from fire assay geochemistry varies from ~0.056 g/t to 2.844 g/t similar to 3-4 g/t Au-grade from field analysis associated with the GQV veinlets and weathered wall rock. The highest Au-grade was obtained from the foliated variety of GQV (QV2). Recovered Au-grains varied in shape and sizes (102-392 μm).
Abstract: The Batouri south Au district of East Cameroon is hosted by biotite-amphibole meta-granites that belong to the Pan-African group of Pre-to Syn D1 and D2 Neoproterozoic granitoids. Hydrothermal activity and Au mineralization in this area is greatly enhanced by the presence of fractures, foliations, faults (sinistral) and vein splays hosted within a ...
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Optimisation of Reflow Profile of Surface Mount Assembly Using Taguchi Design of Experiments
Gabriel Takyi,
Peter Kojo Bernasko
Issue:
Volume 3, Issue 4, August 2015
Pages:
150-169
Received:
25 May 2015
Accepted:
16 June 2015
Published:
2 July 2015
Abstract: A major source of concern in the electronic manufacturing industry is the reliability of solder joints produced by lead-free solders pastes. Research has shown that solder joint produced with a thin layer of intermetallic compounds (IMC) during the reflow process has a higher reliability. The focus of this paper is on the development of a deeper understanding of the lead-free reflow soldering process and to optimise the reflow profile using Taguchi Design of Experiments (DOE). The optimum parameters are those that yield lower IMC layers. The experiment was designed to consider the effect of the following reflow soldering parameters: soak temperature, time above liquidus, soak time and time to peak temperature. The eight (8) reflow profiles studied were derived from the Taguchi DOE which also included three factorial interactions. A stencil with three (3) holes of diameters 3.1 mm, 3.7 mm and 4.3 mm was used in the solder printing process, after which the samples were reflowed. The samples were then thermal cycled, cross-sectioned and finally the IMC image captured and analysed using an optical electron microscope. The analysis of variance (ANOVA) carried out on the results indicate the soak time to be the most significant factor in achieving a solder joint with a thin IMC layer. The next most significant factor was the time above liquidus, and the most significant interaction was found to be the interaction between the soak temperature and time above liquidus. The results indicate a soak time of 60 seconds and time above liquidus of 60 seconds is preferred to achieve a thin IMC layer. The recommended time to peak temperature is 240 seconds and the soak temperature is 150°C. The results can be very useful to researchers and scientists in the surface mount technology (SMT) field, providing an understanding of the effect of the four reflow parameters studied. In addition, the DOE methodology used in this research can be adopted by other process improvement engineers or scientists involved in the optimisation of a process or product.
Abstract: A major source of concern in the electronic manufacturing industry is the reliability of solder joints produced by lead-free solders pastes. Research has shown that solder joint produced with a thin layer of intermetallic compounds (IMC) during the reflow process has a higher reliability. The focus of this paper is on the development of a deeper un...
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Illuminance (lm M-2) of Compact 20W-HCFL Tube
Issue:
Volume 3, Issue 4, August 2015
Pages:
170-179
Received:
11 May 2015
Accepted:
23 May 2015
Published:
5 June 2015
Abstract: It has found that the study on the FL tubes has made with the deliberately modified Ulbricht Spheres for the determination of the luminous efficiency (lm W) that uses in the study on the colorimetry and that invalidates the study on the light sources. The study on the light sources should make with either illuminance (lm m-2), or luminance (cd m-2) and irradiance (W m-2). The rooms in the house should be illuminated with the daytime scenery with the slightly overcastting sky (330 lm m-2) that human eyes adjust for 5 million years. The illuminance (lm m-2) of the commercial compact-20W-HCFL tubes, which have selected from the stores, has determined with the corrected Ulbricht Sphere. The selection criterion is the temperature of the positive column above 60oC of the lighted FL tubes. The examined compact 20W-HCFL tubes have the illuminance (5700 ± 300 lm m-2). Two compact 20W-HCFL tubes that set in a large opaque plastic cover comfortably illuminate the 30 m2 with the 380 lm m-2. The determined W does not involve in the generation energy of the lights in the FL tubes. The reduction of the Wact of the external AC driving circuits remains for a future study.
Abstract: It has found that the study on the FL tubes has made with the deliberately modified Ulbricht Spheres for the determination of the luminous efficiency (lm W) that uses in the study on the colorimetry and that invalidates the study on the light sources. The study on the light sources should make with either illuminance (lm m-2), or luminance (cd m-2)...
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Distribution and Seasonal Variation of Nutrient Salts and Chlorophyll-a in Surface Seawater Along Alexandria Costal Zone Area
Edweb Ali Salem Dango,
Mahmoud Salem Ibrahim,
Mohamed Abel Aziz Okbah,
Mei Ibrahim El Gmaal
Issue:
Volume 3, Issue 4, August 2015
Pages:
180-190
Received:
30 May 2015
Accepted:
12 June 2015
Published:
4 July 2015
Abstract: The aim of the present study is to investigate the hydrographic characteristics, nutrient salts and chlorophyll-a (Chl-a) along Alexandria Costal Zone Area. The study revealed that the pH values lie slightly in the alkaline side, with a range of 7.53 to 8.12, salinity showed a slightly variation, it ranged from 35.34 to 38.28 PSU, the values of dissolved oxygen were fluctuated between 4.77 and 11.13 mgl-1. The annual average of nutrients (μM) was as follow: (7.97 ± 1.72), (0.66 ± 0.14), (2.18 ± 0.73), (0.37± 0.09) and (12.42 ± 4.04) for nitrate, nitrite, ammonium, reactive phosphate and silicate, respectively. Relatively high levels of Chl-a concentrations was recorded during the period of study ranged from 0.38 to 6.96µgl-1 and a positive correlation was found between Chl-a and both NO3, NH4, PO4 and SiO4 (r= 0.383, 0.303, 0.213 and 0.341, respectively). Very high values of N/P ratio were recorded during the study period, this consideration showed that Phosphorus was limiting factor in the study area.
Abstract: The aim of the present study is to investigate the hydrographic characteristics, nutrient salts and chlorophyll-a (Chl-a) along Alexandria Costal Zone Area. The study revealed that the pH values lie slightly in the alkaline side, with a range of 7.53 to 8.12, salinity showed a slightly variation, it ranged from 35.34 to 38.28 PSU, the values of dis...
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Husbandry Practices and Utilization of Camel Products in Borana Zone of Southern Oromia, Ethiopia
Issue:
Volume 3, Issue 4, August 2015
Pages:
191-197
Received:
8 May 2015
Accepted:
22 May 2015
Published:
9 July 2015
Abstract: This survey was conducted in Borana zone to assess camel husbandry and product utilization practices, and identify major constraints of camel production. The result showed that camel was ranked the first economically important livestock species followed by goats and cattle, consecutively. Per producer holding of female of 1-3 year, heifer of 3-5 year, matured female of greater than 5 year, male of 5 year, male of less than 5 year and breeding bull greater than 5 year camel was 4.17, 2.50, 3.83, 1.83, 0.50 and 0.50, respectively. Selection of breeding bull and female camel and uncontrolled mating was common practices. Lactation length was 13.38 months while daily milking frequencies were 3.24 and 2.57 during wet and dry season, respectively. Daily milk yield per camel was 8.4 and 4.75 liters for wet and dry seasons, respectively. A liter of camel milk cost 2.30 and 4 birr during wet and dry season, respectively. Disease, poisonous plants, and low extension and health services were the main problems of camel production. Boosting the capacity of the community on improved husbandry practices and product utilization, and developing coordinated efforts for camel diseases control and prevention schemes should be an assignments of all stakeholders.
Abstract: This survey was conducted in Borana zone to assess camel husbandry and product utilization practices, and identify major constraints of camel production. The result showed that camel was ranked the first economically important livestock species followed by goats and cattle, consecutively. Per producer holding of female of 1-3 year, heifer of 3-5 ye...
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Breast Carcinoma in Younger Algerian Eastern Women: Epidemiological Profile in Series of 135 Cases
Sarra Henouda,
Assia Bensalem,
Leila Rouabah
Issue:
Volume 3, Issue 4, August 2015
Pages:
198-205
Received:
3 July 2015
Accepted:
13 July 2015
Published:
22 July 2015
Abstract: Background: Actually, Breast cancer constitutes one of the most health problems in Algeria, and the leading cause of death among Algerian women. Breast cancer in young women is a rare form, but it has an aggressive behavior associated with a poor prognosis. Aims: this study focuses to report breast cancers phenotype in Algerian younger women. Material and methods: In order to better understand the determinants and tumor biology may explain earlier onset and aggressive breast cancers characteristics in Algeria from December 2011 to July 2014, 135 patients aged 40 years and under diagnosed with breast cancer were included in the study. Results: One hundred thirty-five women recorded, 65.9% patients were aged between 36-40 years. The mean age was 36.29 years. A significantly higher proportion of women were overweight or obese (62.9%). 75.6% patientshad full-term pregnancy. 29.6% breast cancers were diagnosed during pregnancy or after childbirth. 34.1% patients had a family history. In 87.4% of cases the revealing sign was nodule self-examination. Stage II and III associated with nodal extension, higher pathological grade, HR positive, were predominant. Neo-adjuvant was administered to 17.8%. 74.1%patients underwent radical mastectomy using Patey technique with complete axillary dissection.40.7% patients had distal metastases after diagnosis. The mean clinical tumor size was 4.88 cm.71.1% of tumors were invasive ductal carcinoma.69.9% patients had no family history. Conclusion: Breast tumors among Algerian young women are advanced with poor prognosis.
Abstract: Background: Actually, Breast cancer constitutes one of the most health problems in Algeria, and the leading cause of death among Algerian women. Breast cancer in young women is a rare form, but it has an aggressive behavior associated with a poor prognosis. Aims: this study focuses to report breast cancers phenotype in Algerian younger women. Mater...
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Generating Spatial Correlated Binary Data Through a Copulas Method
Renhao Jin,
Sha Wang,
Fang Yan,
Jie Zhu
Issue:
Volume 3, Issue 4, August 2015
Pages:
206-212
Received:
5 July 2015
Accepted:
16 July 2015
Published:
25 July 2015
Abstract: Simulating spatial correlated binary data is very important on many cases, but it is not easily to accomplish, as there are restrictions on the parameters of Bernoulli variables. This paper develops a copulas method to generate spatial correlated binary data. The spatial binary data generated by this method has an inverse spatial pattern comparing with the latent Gaussian random field data, however they have similar empirical variograms, although the closed form for the spatial correlation is not available specifically.
Abstract: Simulating spatial correlated binary data is very important on many cases, but it is not easily to accomplish, as there are restrictions on the parameters of Bernoulli variables. This paper develops a copulas method to generate spatial correlated binary data. The spatial binary data generated by this method has an inverse spatial pattern comparing ...
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The Design and Need for Jigs and Fixtures in Manufacturing
Charles Chikwendu Okpala,
Ezeanyim Okechukwu C.
Issue:
Volume 3, Issue 4, August 2015
Pages:
213-219
Received:
21 June 2015
Accepted:
18 July 2015
Published:
28 July 2015
Abstract: The paper gave a detailed definition of jigs and fixtures, and also identified the numerous advantages that are associated with the use of jigs and fixtures in manufacturing to include: production increase, cost reduction, interchangeability and high accuracy of parts, reduction of the need for inspection and quality control expenses, reduction of accident as safety is improved, automation of machine tool to an appreciable extent, easy machining of complex and heavy components, as well as low variability in dimension which leads to consistent quality of manufactured products. The work also explained that since the design is dependent on numerous factors which are analyzed to achieve an optimum output, that jigs and fixtures should be made of rigid light materials to facilitate easy handling. For adequate strength and rigidity, a mild steel with 16 millimeters diameter was chosen for the design of a sample jig and fixture. Mild steel which contain about 0.29% of carbon are very cheap, and because of their easy availability are often the choicest material for the making of jigs of fixtures.With 1.5 as the material factor ‘k’ for mild steel, a feed rate of 0.17 millimeter per revolution, and a drill diameter of 16 millimeters, the Thrust/Drilling force was calculated as 3094.2 N. The Force acting on each of the lips was calculated as 1700 N, the Torque (M) was gotten as 1360N-mm, while the value of the Clamping Force was also calculated as 4080N. The calculated values confirmed that a 16 millimeter diameter mild will lead to the construction of a rigid and strong jigs and fixtures that will guarantee high machining accuracy, consistent quality of products, and interchangeability. Finall, the paper advocated that jigs and fixtures must be provided with adequate clearance which should allow for variations in size of components especially during forging, milling, and casting operations.
Abstract: The paper gave a detailed definition of jigs and fixtures, and also identified the numerous advantages that are associated with the use of jigs and fixtures in manufacturing to include: production increase, cost reduction, interchangeability and high accuracy of parts, reduction of the need for inspection and quality control expenses, reduction of ...
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Development of New Electrons Sources for coil-EEFL Tube
Issue:
Volume 3, Issue 4, August 2015
Pages:
220-229
Received:
16 July 2015
Accepted:
21 July 2015
Published:
5 August 2015
Abstract: After the critical study on the established FL tubes, it has found a formation of the new internal DC electric power generator in the Ar gas space between the needle cathode and anode. The internal DC electric power generator, which completely isolates from the external DC electric circuit by the electron flow, forms with the volumes of the glow light in front of the needle electrodes that are covered with the layer of the frit glass. The lights are generated by the moving electrons between the cathode and anode of the internal DC electric power generator. The results lead us to the development of the prototype of the coil-EEFL tube that has zero power consumption of the external DC driving circuit.
Abstract: After the critical study on the established FL tubes, it has found a formation of the new internal DC electric power generator in the Ar gas space between the needle cathode and anode. The internal DC electric power generator, which completely isolates from the external DC electric circuit by the electron flow, forms with the volumes of the glow li...
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Coil-EEFL Tubes as Unrivaled Light Source with Small Wcoil Over Solid Light Sources
Issue:
Volume 3, Issue 4, August 2015
Pages:
230-239
Received:
16 July 2015
Accepted:
23 July 2015
Published:
6 August 2015
Abstract: It has found that the active power consumption, Wcoil, of the single coil-EEFL tube that is not related with the energy for the generation of the lights, reduces to below 0.1 Wact of the commercial CCFL tube with the same brightness of the original CCFL tube. The coil-EEFL tubes allow the parallel connection with the single external AC driving circuit. ΣWcoil of 10 coil-EEFL tubes goes down to 0.03 ΣWact. The figure of the merit of the lighting devices is quantum efficiency ηq. The ηq of the FL tubes is the astronomical number that is 1013 visible photons per unit volume (m3) of Ar gas space per unit time (s) by one moving electron in the superconductive vacuum. The coil-EEFL tubes hold the unrivaled advantage with the power consumption and illuminance (lm m-2) over the solid LED lamps that have only ηq ≈ 0.5. A half of the injected electrons inevitably lose the energy by the Joule Heat.
Abstract: It has found that the active power consumption, Wcoil, of the single coil-EEFL tube that is not related with the energy for the generation of the lights, reduces to below 0.1 Wact of the commercial CCFL tube with the same brightness of the original CCFL tube. The coil-EEFL tubes allow the parallel connection with the single external AC driving circ...
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