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Item Effects of environmental disasters on the family in Kenya(Kenyatta Universiry, 2003) Mburugu, Keren G.; Kithinji, Ciriaka T.Thepaper focuses on the main environmental disasters and issues in Kenya. Two main types of environmental issues that impact on thefamily are: Natural disasters such asfloods, earthquakes and landslides; and man-made environmentalproblems which include pollution, deforestation, community displacement, war and its effects such as landmines and bombs; development projects which result in the destabilization of natural ecosystems. The paper links environmental issues and thefamily situation e.g. poverty, poor crop yields leading tofood insecurity; separation of family members; maiming of family members; death of family members as a result of war, disease, poor unhygienic conditions at camps; loss of family property such as farms, livestock, stored grain and homes. Strategies for conquering and coping with the various disasters are suggestedItem Potential of fuel ethanol production from maize stalks in Kenya(Kenyatta University, 2009) Mwangi', Lucy K.; Thoruwa, T.F.N.; Njagi, E.N.M.Item The performance of a solar photovoltaic powered system for grain drying in Lake Victoria basin(Kenyatta University, 2009) Thoruwa, T.F.N.; Langat, C.L.; Chhabra, S.H.; Mahunnah, R.Cereal grains and especially Maize (Zea Mays L.) is the most important and a staple food to 50% of the population estimated at 90 million in East Africa. The East Africa annual production of maize is 12.08 million tons while the corresponding annual post-harvest loss is estimated between 20AO% due to poor processing methods. Besides economic losses, there are negative effects on human and animal health due mycotoxin contamination, food availability and consumption. Maize weevils and pests and fungi contribute storage losses ranging from 9% to 34% of the total output. This paper presents solar drying technology for maize that was developed with an objective to increase grain production through reduction of post harvest loss. This paper presents a simple cabinet photovoltaic dryer that contains a solar air heater connected to rectangular drying bin for maize drying operation. The design is simple and can easily be transported assembled in the field in the maize farming regions. The design consists of four functional units viz. a solar collector covered with top transparent glass glazing, a drying chamber with four DC axial fans rated 12V, 5AW of which 2 are located at inlet and the two at the exhaust section. The fans are powered by a 70W photovoltaic panel-battery system. The air heating collector is 180cm long and 100 cm wide and 25 ern deep containing black absorbers layers. The dryer has maximum loading capacity of 90 kg of maize (viz. equivalent of one 90kg maze bags). Sixteen experimental runs were conducted for drying maize under typical whether conditions at Kenyatta University near the Kenya highlands. Under fair weather conditions, the dryer showed the capability to drying 90 kg of fresh maize from 30% (w.b) to 12% (w.b) within 16 hours or two days of sunshine. The control experiment using traditional sun drying method with the same grain bed thickness at prevailing ambient conditions required 96 hours or 4 days to attain the same moisture level. It is hoped that the findings of research will promote commercial uptake of small scale dryers to reduce crop post-harvest losses and prevent mycotoxin contamination in tropical countries.Item Long-range stream low forecasting using el nino-southern oscillation indicators in the Athi river basin, Kenya(Kenyatta University, 2009) Obiero, CliffordItem Use of biomass gas in running internal combustion engine to generate electricity-a review(SRI secretariat, 2013) Dzombo, D. M.; Kiplimo, R.; Kiplagat, J.K.The world is faced with inadequate fuel supply for household and industrial application. Fossil fuels are mostly used to run machineries with the emission of carbon monoxide, carbon dioxide, oxides of nitrogen, sulphur oxides and particulates from their combustion affecting human health and the environment. Biomass also forms a larger percentage of energy utilized in the household and other areas. Apart from its emission after combustion, biomass waste contributes greatly to pollution. One of the alternatives to effective use of biomass such as rice husk waste is to generate electricity. In this paper a review of energy production from biomass gasification to run internal combustion engines is presented. The gasification process is discussed under drying, pyrolysis, reduction, and oxidation. Different types of designs of gasifiers are reviewed. The current status of gasification technology in developed and developing countries is discussed. The gas generated is introduced to a modified engine with small amounts of diesel used to ignite the mixture. This is because the producer gas cannot ignite by itself under the prevailing pressure. Thus for a compression ignition engine to run on producer gas they have to be either; a dual fuel engine or, converted into a spark ignition engines. Since diesel engines have compression ratios between 16 – 20 and are run at lower revolutions per minute than gasoline engines they are ideally suited to run on producer gases without spark ignition. The paper also looks at current work that has been done and identifies areas that need further research.Item Determinants of technology innovation implementation effectiveness in higher education institutions(IEEE, 2013) Kandiri, John; Muganda, N.Higher education institutions have continued to acquire technologies with alacrity. However, the transition from adoption to application in teaching and learning has been below expectations. This exploratory study investigated the lack of cadence between adoption and effective implementation of educational technology initiatives. The study was based on PHEA-ETI projects that ran between June 2008 and June 2012. The projects entailed implementation of technology initiatives for example animating science content among others. A questionnaire was sent to all persons involved in the implementation of the projects. Out of the 163 targeted respondents, 105 usable responses were received. Team leaders were interviewed with focus groups held with implementation teams. The study adopted: top management, financial motivation, organizational culture. The new model added the variables: team leadership, monitoring and evaluation and innovation efficacy. When the data was analysed using SPSS version 17, the results confirmed determinants from earlier studies while also showing that team leadership and project efficacy were significant factors to consider in technology innovation implementation.Item Section VI-Environment and agriculture(Kenyatta University, 2014)Item Section IV- Health(Kenyatta University, 2014) John, TharakanItem Section II: Energy(Kenyatta University, 2014) Kiplagat, Jeremiah K.Item Section III: Water and sanitation(Kenyatta University, 2014) John, TharakanItem Section VII- Knowledge and technology transfer(Kenyatta University, 2014) Gada, KadodaItem Section 1: Green economy and innovation(Kenyatta University, 2014) John, TharakanItem The International Network on Appropriate Technology--Proceedings of the 6th International Conference on Appropriate Technology “Appropriate Technology for the 21st Century: Technological Innovation to Empower Africa”(Kenyatta University, 2014) Kiplagat, Jeremiah K.Proceedings of the 6th International Conference on Appropriate Technology “Appropriate Technology for the 21st Century: Technological Innovation to Empower Africa” Hosted at the Kenyatta University Conference Center Nairobi, Kenya, November 25 – 29, 2014 SECTION II: ENERGY Edited by Jeremiah K. KiplagatItem Section VIII: Policy and standards(Kenyatta University, 2014) Kudakwashe, MadzimaItem Section V- Construction and infrastructure(Kenyatta University, 2014)Item Combustion characteristics and energy potential of municipal solid waste in Arusha City-Tanzania(Kenyatta University, 2014-11) Sarakikya, Halidini Z.; Kiplagat, Jeremiah K.Municipal Solid Waste (MSW) generation has been in the increase due to the population growth, changing life style, technology development and increased consumption of goods. The increase of waste generation may lead to environmental and social problems such as water contamination, land and atmospheric pollutions, provide breeding grounds for insects and rats, risk of fire, bad odors and potential cause of illnesses. The combustion properties and study of energy potential from municipal solid waste was undertaken. The energy flow (exothermic and endothermic) and thermal degradation analysis were carried out using differential scanning calorimetry and thermo – gravimetric analyzer respectively. The sample of composition of municipal solid waste examined included papers, cardboard, wood, textile, rubber, polyethylene Teraphthalate (PETE), low density polyethylene (LDPE) and food waste. Composition of these materials were heated in a NETZSCH STA, 409 TGA apparatus and experiments were performed at heating rate of 10○C/min, in the nitrogen atmosphere at temperature between room temperature and 1100 ○C. The thermal degradation characteristics of the MSW were obtained using thermo gravimetric analyzer (TGA) and derivative of thermo gravimetric (DTG). It was observed that municipal solid waste is less reactive to combustion, but its reactivity can be improved through pre-treating process like drying, shredding and removing non combustible materials such as metals. Also pyrolysis and gasification can be used to convert MSW to gaseous fuel. The energy content of the solid waste tested was about 12MJ/kg. The elemental composition shows that Municipal solid Waste contains 50% and 5% of carbon and hydrogen respectively. Keywords: Municipal Solid Waste, Thermal behavior, Thermo gravimetric AnalysisItem Optimized K-Means clustering algorithm using an intelligent stable-plastic variational autoencoder with self-intrinsic cluster validation mechanism(ICONIC, 2020-09-24) Gikera, Rufus; Mambo, Shadrack; Mwaura, JonathanClustering is one of the most important tasks in exploratory data analysis [1, 55, 59]. K-means are the most popular clustering algorithms [51, 61]. This is because of their ability to adapt to new examples and to scale up to large datasets. They are also easily understandable and computationally faster [57, 60, 3, 62]. However, the number of clusters, K, has to be specified by the user [50]. Random process is the norm of searching for appropriate number of clusters, until convergence [53, 5]. Several variants of the k-means algorithm have been proposed, geared towards optimal selection of the K [8, 48]. The objective of this paper is to analyze the scaling up problems associated with these variants for optimizing K in the k-means clustering algorithms. Finally, a more enhanced hybrid autoencoder-based k-means will be developed and evaluated against the existing variants.