oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

4 ( 1 )

2019 ( 43 )

2018 ( 79 )

2017 ( 70 )

Custom range...

Search Results: 1 - 10 of 31024 matches for " Cuthbert Z. Kimambo "
All listed articles are free for downloading (OA Articles)
Page 1 /31024
Display every page Item
Hydropower in the Context of Sustainable Energy Supply: A Review of Technologies and Challenges
Chiyembekezo S. Kaunda,Cuthbert Z. Kimambo,Torbjorn K. Nielsen
ISRN Renewable Energy , 2012, DOI: 10.5402/2012/730631
Abstract:
Potential of Small-Scale Hydropower for Electricity Generation in Sub-Saharan Africa
Chiyembekezo S. Kaunda,Cuthbert Z. Kimambo,Torbjorn K. Nielsen
ISRN Renewable Energy , 2012, DOI: 10.5402/2012/132606
Abstract:
Hydropower in the Context of Sustainable Energy Supply: A Review of Technologies and Challenges
Chiyembekezo S. Kaunda,Cuthbert Z. Kimambo,Torbjorn K. Nielsen
ISRN Renewable Energy , 2012, DOI: 10.5402/2012/730631
Abstract: Hydropower is an important renewable energy resource worldwide. However, its development is accompanied with environmental and social drawbacks. Issues of degradation of the environment and climate change can negatively impact hydropower generation. A sustainable hydropower project is possible, but needs proper planning and careful system design to manage the challenges. Well-planned hydropower projects can contribute to supply sustainable energy. An up-to-date knowledge is necessary for energy planners, investors, and other stakeholders to make informed decisions concerning hydropower projects. This is basically a review paper. Apart from using expert knowledge, the authors have also consulted extensively from journals, conference papers, reports, and some documents to get secondary information on the subject. The paper has reviewed the world energy scenario and how hydropower fits in as the solution to the global sustainable energy challenge. Issues of hydropower resource availability, technology, environment and climate change have been also discussed. Hydropower is sensitive to the state of environment, and climate change. With global climate change, though globally the potential is stated to slightly increase, some countries will experience a decrease in potential with increased risks. Adaptation measures are required to sustainably generate hydropower. These are also discussed in the paper. 1. Introduction 1.1. World Energy Scenario and Sustainable Energy In this era, concerns about environment and climate change management influence choices investors and international financing institutions make concerning energy projects [1]. The word “environment” can be defined in many ways depending on the discipline; but it is broadly understood to refer to surroundings that interact with life on earth. The surroundings can be divided into nonliving and living components. The important point concerning environment, according to Gorshkov and Makarieva [2], is that it provides resources, such as energy, that support life on earth. Since energy is sourced and processed into a usable form from the environment, activities pertaining to its extraction, transportation, conversion, and utilisation impact the environmental system. The impacts are pronounced in thermal energy systems. For fossil fuel energy systems, it is also not possible to totally avoid emissions and environmental setbacks because of combustion. During the combustion process, energy is converted from chemical into heat and the gaseous products of combustion are ejected from the system at a higher
Potential of Small-Scale Hydropower for Electricity Generation in Sub-Saharan Africa
Chiyembekezo S. Kaunda,Cuthbert Z. Kimambo,Torbjorn K. Nielsen
ISRN Renewable Energy , 2012, DOI: 10.5402/2012/132606
Abstract: The importance of renewable energy such as small hydropower for sustainable power generation in relation to its capacity to contribute towards alleviating acute shortage of rural electricity supply in the sub-Saharan African region has been discussed. A relatively comprehensive small hydropower technology review has been presented. Rural electricity supply scenario in the region has been presented and, in general, the region has very low electricity access levels coupled with various challenges. Small hydropower technology has been discussed as one of the promising decentralised power generation system for rural electricity supply in the region. Despite challenges in data acquisition, this paper has shown that the SSA has significant hydropower resources, but the level of installation is very low. Challenges hampering SHP technology development in the region have been identified and discussed, such as those concerning technology, climate change, finance, and policy. This is basically a paper where the authors consulted a wide range of literature including journals, conference proceedings, and reports as well as expert knowledge in the area. It is hoped that this paper contributes to the information base on SHP technology which is quite lacking in the region. 1. Introduction Sustainable electricity supply not only supports social and economic development processes but also environmental and global climate change management and hence its importance in attainment of the Millennium Development Goals. Currently, there is an increasing electricity demand in industry, household, and services sectors in developing countries to support social-economic development activities. If this electricity is generated unsustainably and the trend is not controlled, it could lead to exacerbation of environmental and climate change management problems which the world is currently experiencing. The energy supply sector (mainly for generation of electricity), according to the Intergovernmental Panel on Climate Change (IPCC), is the largest contributor to the global human-induced greenhouse gas (GHG) emissions (responsible for global warming—main cause of climate change); in 2004, energy supply sector contributed to around 26% of global GHG emissions, followed by forestry (17%), agriculture (13%), and transport (13%) [1]. Developing countries, especially those from sub-Saharan African (SSA) countries (sub-Saharan Africa as a geographical term refers to the area of the continent of Africa that lies south of the Sahara. The countries in the sub-Saharan African region are Angola,
Willingness of high school students to be treated by an HIV infected health practitioner. a study done in dar es salaam, Tanzania.
A Kimambo
Dar Es Salaam Medical Students' Journal , 2010,
Abstract: OBJECTIVE To assess willingness of high school students to be treated by HIV/AIDS infected dental practitioners in Ilala municipality, Dar Es Salaam, Tanzania. METHODOLOGY This was a descriptive cross-sectional study. RESULTS More than half (52.8%) of the high school students showed fear of being treated by HIV/AIDS infected dental practitioner, with 175 (55.4%) out of 316 students fearing even to be clinically examined by HIV positive dental practitioner. Out of 316 students, 163 (51.6%) students showed no problem in consulting a HIV/AIDS infected dental practitioner for dental problems. There were 170 (53.8%) respondents who were uncomfortable to undergo dental treatment provided by HIV positive dental practitioner. CONCLUSION The results of this study showed that there is fear an element of negative attitude and stigmatization among high school students on being treated by HIV/AIDS infected health care practitioner.
QoS in Node-Disjoint Routing for Ad Hoc Networks  [PDF]
Luo LIU, Laurie CUTHBERT
Int'l J. of Communications, Network and System Sciences (IJCNS) , 2008, DOI: 10.4236/ijcns.2008.11011
Abstract: Ad hoc network (MANET) is a collection of mobile nodes that can communicate with each other without using any fixed infrastructure. To support multimedia applications such as video and voice MANETs require an efficient routing protocol and quality of service (QoS) mechanism. Node-Disjoint Multipath Routing Protocol (NDMR) is a practical protocol in MANETs: it reduces routing overhead dramatically and achieves multiple node-disjoint routing paths. QoS support in MANETs is an important issue as best-effort routing is not efficient for supporting multimedia applications. This paper presents a novel adaptation of NDMR, QoS enabled NDMR, which introduces agent-based SLA management. This enhancement allows for the intelligent selection of node-disjoint routes based on network conditions, thus fulfilling the QoS requirements of Service Level Agreements (SLAs).
Bicarbonate Secretion in the Murine Gallbladder - Lessons for the Treatment of Cystic Fibrosis
Cuthbert AW
JOP Journal of the Pancreas , 2001,
Abstract: The epithelium lining the gallbladder of mammalian species has absorptive and secretory functions. An important function is the secretion of a bicarbonate rich fluid that helps neutralise stomach acid and provides an appropriate environment for intestinal enzymes. In cystic fibrosis (CF) this secretory function is lost. This study concerns the bicarbonate secreting activity of murine gallbladders in vitro using wild type and CF mice and four main questions are considered as follows: a) Does the murine gallbladder secrete bicarbonate electrogenically and is this prevented in CF? b) Can the secretory activity in CF gallbladders be restored by gene therapy or pharmacologically? c) How is the cystic fibrosis transmembrane conductance regulator (CFTR) involved in bicarbonate secretion? d) Does the data offer prospects for the treatment of CF?. Work from both the author's laboratory and the literature will be reviewed. Consideration of the currently available data indicates that the wild type murine gallbladder does secrete bicarbonate electrogenically and that this is absent in CF mice. Further it has been demonstrated that bicarbonate secretory activity can be restored by both gene therapy and by the use of drugs. The role of CFTR in bicarbonate secretion remains equivocal. Much evidence suggests that CFTR can act as a channel for HCO(3)(-) ions as well as Cl(-) ions, while others propose a parallel arrangement of CFTR with a Cl(-)/HCO(3)(-) exchanger is necessary. The matter is further complicated by the regulatory role of CFTR on other transporting activities. Opportunities for possible application to man are discussed.
Climate Change Adaptation and Vulnerability: A Case of Rain Dependent Small-Holder Farmers in Selected Districts in Zambia  [PDF]
Cuthbert Casey Makondo, Kenneth Chola, Blesswell Moonga
American Journal of Climate Change (AJCC) , 2014, DOI: 10.4236/ajcc.2014.34034
Abstract: Food crop production by small-holder farmers in Africa is particularly vulnerable to climate change, given high dependence on rainfall coupled with limited adaptive capacity. In Zambia, smallholder farmers contribute about 79% of national stable food requirements particularly maize. This paper attempted to establish levels of food security in each of the three agro-ecological zones of Zambia, and evaluated the current adaptive measures of rain dependent small-holder farmers against climate change risks. The challenges farmers are facing in adapting to the change risks were identified and livelihood vulnerability assessed. The findings indicate that rain dependent small-holder farmers in Zambia are highly vulnerable to weather related shocks which impact greatly on their food production; and that the levels of vulnerability vary across gender and per agro-ecological zone. After the evaluation of scenarios including staple food crop yields (maize), the authors conclude that most rain-fed small-holder farmers in Zambia (about 70%) are facing considerable hardships in adapting to the changing climate, which in turn, undermines their contribution to food security. While efforts by government have been made to assist farmers towards climate change adaptation, there still remains many challenges to achieve the desired outcomes. Most farmers (66%) are unable to afford certain alternatives, such as those of agro-forestry or conservation. Difficulties in accessing markets, poor road infrastructure, fluctuating market prices, high costs and late deliveries of farming in-puts were found to be among the major challenges that farmers are facing in Zambia. There are also no systematic early warning systems in place against natural hazards and disasters. This makes farming a difficult undertaking in Zambia.
Energy efficient refuse derived fuel (RDF) from municipal solid waste rejects: a case for Coimbatore
Offor N Kimambo,P Subramanian
International Journal of Environment , 2014, DOI: 10.3126/ije.v3i2.10530
Abstract: In this paper production of energy efficient Refuse Derived Fuel (RDF) from municipal solid waste rejects was carried out during August 2012 – April 2013 in Coimbatore City India. Municipal Solid wastes rejects (paper, plastics with exception of polyvinyl chloride, textiles) were collected from waste dump yard of Coimbatore City. Sawdust, coir dust, water hyacinth and rice husk were mixed with the collected wastes at a fixed amount of 20 percent. After grinding, cassava starch was used as a binder to produce RDF briquettes with the help of uniaxial piston briquettes making machine. Physical, chemical and thermal characteristics of the RDF were studied to assess their potential use as energy efficient material. The analyses were divided into three categories namely, physical, proximate and ultimate analyses. Results indicated that, under physical and proximate analyses; impact resistance index (IRI) for all the RDF samples were 200, density were less than 1 kg cm -3 , moisture were less than 10 % wt, ash content varied from 2.8 to 9.2 % wt, whilst volatile mater had mean value of 83.1 % wt and fixed carbon which is by subtraction ranged from 1.4 to 9.2 % wt. With respect to Ultimate analysis, Oxygen, carbon, hydrogen varied from 27.01 to 39.78 % wt, 44.8 to59.7 % wt, 5.9 to 8.1 % wt respectively. On the other hand nitrogen, sulfur and chlorine ranged from 0.18 to 0.87 % wt, 0.27 to 0.71 % wt and 0.339 to0.521 % wt respectively. Calorific values (high heating values) ranged from 5085 to 6474.9 kcal kg -1 . The results were compared with Energy research Centre for the Netherland database and noted that with exception to moisture, fixed carbon and hydrogen other parameters had a significant lower or higher differences. From the study, RDF from municipal solid wastes rejects along with the additives produced high energy efficient materials. DOI: http://dx.doi.org/10.3126/ije.v3i2.10530 International Journal of the Environment Vol.3(2) 2014: 205-215
Reciprocal Teaching of Lecture Comprehension Skills in College Students
Norman Spivey,Andrea Cuthbert
The Journal of Scholarship of Teaching and Learning , 2006,
Abstract:
Page 1 /31024
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.