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Item 2013 ISES Solar World Congress Promotion of PV Uptake and Sector Growth in Kenya through Value Added Training in PV Sizing, Installation and Maintenance(Science Direct, 2014) Justus Simiyu; Sebastian M. Waita; Alex Ogacho; Robinson MusembiSub-Saharan Africa, and more specifically the East African region, has the lowest rates of access to electricity in the world. On average, at most 15% of the rural population has access to electricity. Rural households and remote institutions use traditional energy sources such as charcoal, firewood, kerosene and diesel for generator sets, batteries and dry cell batteries. On the other hand, the region is one of the most promising in the world in economic development with growth levels being high and market saturation is a far away future problem. This growth has however been hampered by several factors with lack of energy being one of them. Kenya being one of the countries in the region faces a similar problem with the traditional sources of hydro facing weather related challenges. The situation is more wanting in the rural setting having only achieved electrification rates of between 5 and 10%. The rural being where the majority of low-income earning groups reside is further compounded with large geographical imbalance in electricity demand and supply. The main challenge to adopting pv utilization however, is lack of local capacity to handle the uptake all the way from solar home systems to grid connected and hybrid systems. According to Kenya Renewable Energy Association (KEREA), it is estimated that between 800 and 1000 pv technicians have been in practice since this sector started in Kenya in the late eighties, majority of them having the basic skills but no formal training to provide the service. They however have been offering necessary service to end-users and are hence an important aspect in the pv sector as a whole. Currently the pv (mainly SHS) comprise an over the counter trade system which provides loopholes when it comes to quality of products and installation. To safeguard the quality and safety of installations, formal training has to be incorporated in the system.Item A botanical inventory and diversity assessment of Mt. Marsabit forest, a sub-humid montane forest on the arid lands of northern Kenya(Wiley, 2007) Githae, E. W.; Chuah-Petiot, M.; Mworia, J. K.; Odee, D. W.A botanical inventory and diversity of trees, shrubs (≥5 cm diameter at breast height [dbh]), herbs,climbers and lianas was assessed in plots (154) of 20 × 5 m in Mt. Marsabit forest, northern Kenya. Werecorded 52 species of trees and shrubs, twelve species of herbs and six species of climbers and lianas.They belonged to 35 families and 64 genera. Rubiaceae was the richest family with nine species followedby Euphorbiaceae (six), Oleaceae (five), Rutaceae (four), Capparaceae, Labiatae and Leguminosae (threeeach). The rest of the families were represented by one or two species. Rinorea convallarioides (Bak.f.)Eyles ssp. marsabitensis Grey-Wilson (Violaceae), an endemic species, and Drypetes gerrardii Hutch.(Euphorbiaceae), were the two most important species, accounting for more than third of the combinedimportance value. Species diversity indices were 2.735 (Shannon–Wiener), 0.88 (Simpson's) and 0.296(Evenness). There was a strong evidence of disturbance arising from anthropogenic and wildlife foragingactivities. This inventory has affirmed Mt. Marsabit forest as a unique habitat for several endemic, rare,threatened or vulnerable plant species, which should be conserved.Item A Comparative Study of the Physiochemical and Bacteriological Parameters of Potable Water from Different Sources in Kitui County, Kenya(Journal of Environment and Earth Science, 2022-11-30) T, Wambua; W, Hunja Carol; Josphert, Kimatu; M, Muluvi Geoffrey; U, Kitheka Johnson; Festus, Mutiso; L, Githenya; K, Ndufa James; Kennedy, MutatiDeveloping nations are experiencing an ever-increasing demand for safe water due to climate change and the ever-increasing human population. Various strategies including construction of shallow wells, boreholes and sand dams along the river are done to make water available to various households. However, availability of water sources near are faced with challenges of pollution from a variety of sources. The aim of this study was to determine the levels of selected bacteriological and physico-chemical parameters in three potable water sources namely Kiembeni borehole, Mwitasyano River and Kalundu Dam in Kitui County. The quality of this water was compared to the standards for potable water prescribed by Kenya Bureau of Standards (KEBS). Representative sampling was conducted during the wet season (October 2019) and the dry season (August 2020) in the three sampling sites. The samples were analyzed for physico-chemical parameters: pH, color, turbidity, alkalinity, conductivity, iron, calcium, magnesium, hardness, chloride, fluoride, sulphates, ammonia, total dissolved solids and bacteriological parameters: total and fecal coliform. The analysis was performed at the Kenya Water Institute (KEWI) laboratory using standard procedures. The values obtained for the different water sources in the wet season and dry season were pooled and mean values calculated to determine the overall quality of drinking water. The results indicated that all the water sources had fecal coliform levels unsuitable for drinking water. Most of the values obtained for pH, color, alkalinity, conductivity, calcium, fluoride and sulphates in all sources of water were within the recommended potable water standards by KEBS. However, turbidity, iron and total coliform obtained values for borehole water samples were not within the recommended KEBS standards. The river and dam water samples were within the recommended standards for magnesium, hardness, chloride, ammonia and total dissolved solids. Although results indicate that some of the physico-chemical parameters were in conformance with the recommended standards, the overall bacteriological parameters render the water unsuitable for drinking. Thus, public health intervention programmes should be focused on addressing various sources of water pollution including regular disinfection of water.Item A Hybrid of Fuzzy Logic and Sliding Mode Techniques for Photovoltaic Maximum Power Point Tracking Systems Under Partial Shading(University of Nairobi Research Archive, 2020-11-20) Gathoni, Robinson N.Solar energy harvesting using photovoltaic (PV) modules have been one of the most commonsources of renewable energy for several decades. These modules have been used as a sourceof electricity for households, industries, in stand-alone, and grid-connected solar plants. Themodules consist of semi-conductor solar cells combined in series and parallel. In order to makea solar system, the modules are usually linked in series. The performance of a solar system isaffected by environmental factors like varying radiance and temperatures, shadowing caused byhigh-rise buildings, birds, fog, trees and dust. Such varying environmental conditions affect asolar cell's efficiency. Nevertheless, given all the effort made to mitigate the impact of all theseenvironmental threats, some of the natural occurrences such as varying radiance, clouds, dust,wind-speed and change in temperature, can not be done away with. To improve the e ciencyof the entire solar system, power extraction must be optimized under all weather conditions.Fuzzy logic and sliding mode techniques are e cient, fast and reliable methods of trackingthe maximum power point that have been used in this study. The application of these twoapproaches substantially increases system e ciency for all environmental conditions includingpartial shading instances. The sliding mode technique is a very fast, stable and robust algorithmthat work e ectively under very stable weather condition while the fuzzy logic has beenexploited under partial shading conditions. Both methods rely heavily on a good understandingof the characteristics of PV modules, which are studied using I-V, P-V or P-I curves. In thiswork, three new algorithms have been used to simulate and model the characteristics of a PVmodule.The algorithms are based on a single diode equivalent circuit, which has been chosen dueto the simplicity of simulation and modeling and provides a fast convergence time. The algorithmsare classi ed according to the method of obtaining the best values of the unknownve parameters of the diode model. Ideality factor (A), saturation current (Io), photocurrentiv(Iph), series (Rs) and parallel (Rp) resistances are the ve unknown parameters to be determinedfor characterization of a PV module using a diode model. These parameters have beenextracted using the I-V curve's three critical points at short circuit point (SCP), open circuitpoint (OCP) and maximum power point (MPP). The rst algorithm has been based on thechoice of ideality factor below the optimal ideality factor (Ao), such that 0 A Ao, whereasthe other parameters depends heavily on the choice of A. The second algorithm has been basedon the choice of ideality factor in the neighborhood of Ao and the third algorithm has beenbased on A Ao. The three methods have been utilized to characterize the solar module usingI-V and P-V curves and have output power errors of less than 0.5%.For proof of concept of the three algorithms, PV module with IEC61215 speci cations havecarefully selected from Kyocera- KC130CGT. Additional experimental work has been carriedout at Solinc Kenya Ltd using Solinc 60Wp and 250Wp PV modules, similar to those mountedon the rooftop of the building in Chiromo at School of Physical Sciences.Item A review of the changes in phytoplankton community structure and ecology in lake naivasha, kenya(Academic Journals, 1970-01-01) Argwings Owino Omondi, Steve Opiyo Balaka, George Ogendi Mokua, James Onchieku Mokua, Steve Oduor OmondiPhytoplankton community structure plays a vital role in freshwater ecosystems. Besides the provision of dissolved oxygen through photosynthesis, they also form an important diet for several fish and zooplankton species. Plankton are also used as biological indicators of water quality. The objective of this paper is to provide a comprehensive review on the changes in phytoplankton community structure and their ecological functional roles. Phytoplankton are the primary producers in Lake Ecosystem. The diversity, distribution, and abundance of phytoplankton are influenced by both abiotic and biotic factors. Lake Naivasha has undergone drastic ecological changes due to the growth in human population, horticultural and floricultural developments and changes in its fisheries. Lake Naivasha is surrounded by horticultural farms that are greatly influencing its ecosystem health and the major fish species in the lake are of introduced species. These anthropogenic activities together with hydrological changes are expected to play a role in the changes in phytoplankton community structure. Previous investigations indicate that there are more than 143 species of phytoplankton and seasonal shift in phytoplankton dominance overtime between Chlorophyta, Bacillariophyta, and Cyanophyta. Due to various limnological, hydrological, and ecological changes being witnessed in the Lake, there is need for the monitoring of phytoplankton community structure. Such information would be useful in the Lake’s management and conservation.Item A Review of the Current Trends in the Production and Consumption of Bioenergy(Sami Publishing Company(SPC), 2021) Korir, Benjamin K.; Kibet, Joshua; Mosonik, Bornes C.With the current traditional fossil fuels depleting at an alarming rate coupled with environmental degradation because of toxic emissions, there is a mounting desire in search of renewable and sustainable energy resources. In this regard, bioenergy is considered one of the greatest potential to address the global energy demands in order to foster confidence in energy security, economic sustainability, and environmental protection. Global use of biomass to generate electricity and enhanced green energy transport is expected to increase in the near future. Accordingly, the demand for renewable energy is aimed at minimizing energy poverty and mitigation against climate change. Bioenergy despite bioconversion challenges is one of the key solutions to the world’s current energy demands. Model bioenergy plant sources – Croton megalocarpus, palm oil, Jatropha, and soybeans are briefly discussed in this review as major sources of bioenergy. The increased focus on bioenergy has been necessitated by high oil and gas prices, and the desire for sustainable energy resources. Nonetheless, corrupt practices and lack of political goodwill has hampered efforts towards achieving the full utilization of bioenergy. Corruption has been widely cited as a major setback to bioenergy development in a range of global jurisdictions. In order to minimize environmental damage, carbon trade has been projected as a necessary action by developing countries to reduce carbon emissions. Generally, the analysis of the use of fossil fuels across the world shows a strong interrelationship involving energy utilization, degradation of air quality, and environmental health concerns.Item A Review of the Current Trends in the Production and Consumption of Bioenergy(Sami Publishing Company, 2021-02-01) Korir, Benjamin K.; Kibet, Joshua; Mosonik, Bornes C.With the current traditional fossil fuels depleting at an alarming rate coupled with environmental degradation because of toxic emissions, there is a mounting desire in search of renewable and sustainable energy resources. In this regard, bioenergy is considered one of the greatest potential to address the global energy demands in order to foster confidence in energy security, economic sustainability, and environmental protection. Global use of biomass to generate electricity and enhanced green energy transport is expected to increase in the near future. Accordingly, the demand for renewable energy is aimed at minimizing energy poverty and mitigation against climate change. Bioenergy despite bioconversion challenges is one of the key solutions to the world’s current energy demands. Model bioenergy plant sources – Croton megalocarpus, palm oil, Jatropha, and soybeans are briefly discussed in this review as major sources of bioenergy. The increased focus on bioenergy has been necessitated by high oil and gas prices, and the desire for sustainable energy resources. Nonetheless, corrupt practices and lack of political goodwill has hampered efforts towards achieving the full utilization of bioenergy. Corruption has been widely cited as a major setback to bioenergy development in a range of global jurisdictions. In order to minimize environmental damage, carbon trade has been projected as a necessary action by developing countries to reduce carbon emissions. Generally, the analysis of the use of fossil fuels across the world shows a strong interrelationship involving energy utilization, degradation of air quality, and environmental health concerns.Item A review of the impacts of invasive aquatic weeds on the bio- diversity of some tropical water bodies with special reference to Lake Victoria (Kenya)(Biodiversity, 0020-12-30) Aloo, Peninah; Ojwang, William; Omondi, Reuben; Njiru, James Murithi; Oyugi, DalmasAquatic weeds may be defined as troublesome or unsightly plants growing in abundance inaquatic situations where they are not wanted. These plants are either adapted to continuoussupplies of water or are at least tolerant to waterlogged soil conditions for substantial periodsof time. The wide range of adaptation to varying amounts of water, and the impossibility ofsharply distinguishing between aquatic and terrestrial environments, makes it difficult toprecisely define an aquatic plant. The menace of water weeds is reaching alarming proportions in many parts of the world, especially in tropical water bodies where they have led toserious ecological and economic losses. Lake Victoria, Kenya, which is the largest freshwaterbody in the tropics, has undergone serious ecological changes including over-exploitationof its fishery resources, degradation of the catchment area, introduction of exotic fish speciesand invasion by the water hyacinth, Eichhornia crassipes (Mart.) Solms (Pontederiaceae),among others. The presence of the weed in the lake has led to many problems includingblockage of water pumps, reduced fishing activities and increase in water borne diseasessuch as schistosomiasis. Positively, aquatic weeds constitute a free crop of great potentialvalue; they are a highly productive crop that requires no tillage, fertilizer, seed, or cultivation.Moreover, these plants have the potential for exploitation as animal feed, human food, sourceof food to some aquatic organisms, soil additives, fuel production, wastewater treatment,source of raw materials and habitat to many organisms. This paper reviews the effects ofaquatic weeds in aquatic systems with examples from some selected waterbodies and specialreference to Lake Victoria.Item A review of the impacts of invasive aquatic weeds on the bio- diversity of some tropical water bodies with special reference to Lake Victoria (Kenya)(Biodiversity Journal, 2013-12-30) Aloo, Peninah; Ojwang, William; Omondi, Reuben; Njiru, James Murithi; Oyugi, DalmasAquatic weeds may be defined as troublesome or unsightly plants growing in abundance inaquatic situations where they are not wanted. These plants are either adapted to continuoussupplies of water or are at least tolerant to waterlogged soil conditions for substantial periodsof time. The wide range of adaptation to varying amounts of water, and the impossibility ofsharply distinguishing between aquatic and terrestrial environments, makes it difficult toprecisely define an aquatic plant. The menace of water weeds is reaching alarming proportions in many parts of the world, especially in tropical water bodies where they have led toserious ecological and economic losses. Lake Victoria, Kenya, which is the largest freshwaterbody in the tropics, has undergone serious ecological changes including over-exploitationof its fishery resources, degradation of the catchment area, introduction of exotic fish speciesand invasion by the water hyacinth, Eichhornia crassipes (Mart.) Solms (Pontederiaceae),among others. The presence of the weed in the lake has led to many problems includingblockage of water pumps, reduced fishing activities and increase in water borne diseasessuch as schistosomiasis. Positively, aquatic weeds constitute a free crop of great potentialvalue; they are a highly productive crop that requires no tillage, fertilizer, seed, or cultivation.Moreover, these plants have the potential for exploitation as animal feed, human food, sourceof food to some aquatic organisms, soil additives, fuel production, wastewater treatment,source of raw materials and habitat to many organisms. This paper reviews the effects ofaquatic weeds in aquatic systems with examples from some selected waterbodies and specialreference to Lake VictoriaItem A review of thermal energy storage designs, heat storage materials and cooking performance of solar cookers with heat storage(Elsevier, 2017-08-01) Nkhonjera, Lameck; Bello-Ochende, Tunde; John, Geoffrey; King’ondu, Cecil K.This paper discusses the thermal energy storage units, heat storage materials and cooking performance of solar cookers with heat storage surveyed in literature. It is revealed that rectangular and cylindrical containers are widely used in the heat storage devices of the solar cookers. The geometry of the storage units, however, depended on the mode of heat transport into the storage medium and out to the cooking vessel from which, three categories of solar cookers (2-stage, 3-stage, and 4-stage solar cookers) are identified. Furthermore, oils and organic phase change materials dominated in the sensible and latent heat storage units respectively. Additionally, the inclusion of high thermal conductive material into the storage medium was the principal technique used in enhancing effective thermal conductivity. Besides, it is shown that there is no significant difference between the cooking power of cookers equipped with sensible and latent heat storage units. However, the design parameters of the cookers as well as thermal diffusivity of the storage medium greatly influenced the cooking power. The 3-stage cookers outperformed their 2-stage counterparts whereas cookers with cooking vessels integrated to the thermal storage unit outperformed the ones with non-integrated cooking vessels. On the other hand, lower thermal diffusivity of the storage medium increased cooking power in cookers with sensible heat storage but decreased the cooking power in cookers with latent heat storage. Finally, it is shown that the quest for the development of high temperature thermal storage units, and the optimization of the geometry as well as heat transfer characteristics of thermal energy storage units remain the potential areas of research in heat storage for cooking.Item A Review of Toxic Metals and Hazardous Organics in Wood Treatment Sites and Their Etiological Implications(Journal of Chemical Reviews, 2022-02-07) Miranji, Edwin K.; Kipkemboi, Pius K.; Kibet, Joshua K.Increased natural and human activities over the last century have led to excess levels of inorganic and organic pollutants into the environment and natural ecosystems. This review critically examines heavy metal and organic pollutants' role in wood treatment sites and their etiological consequences. These pollutants are not only recalcitrant but also tenacious to degradation under ordinary conditions. Although some heavy metals are essential to human health, they are toxic at elevated concentrations. Heavy metals feature carcinogenic properties and cause serious health risks to live systems and the environment because of their bio-accumulative, non-degenerative, and refractory characteristics. On the other hand, organic pollutants are readily introduced into the ecosystem from irresponsible use of detergents, volatile organic compounds, paints, pesticides, and wood preservatives. During the wood treatment process, various chemicals are used to enhance durability. Nevertheless, the use of wood preservatives such as chromated copper arsenate (CCA) and pentachlorophenol (PCP) potentially induces pollutants considered detrimental to human health and the ecological environment. Remediation of wood treatment sites using phytomanagement strategies and nanotechnologies has been presented in this review. Therefore, some challenges and recommendations for further research and applications are herein presented.Item A Simple Low Cost Solar Panel/cell Characterization Experiment for Senior Undergraduate Students(ISES, 2015-11-11) Sebastian Waita*, Justus Simiyu, Alexander N. Kiragu, Vivian Imali and Bernard AdudaA simple low cost solar cell characterization experiment has been developed for senior undergraduate students in the Department of Physics, University of Nairobi. Experiments were conducted with solar panels (also called solar modules/photovoltaic modules) rated 20 W and 40 W peak power on different sunny days on the roof top of Physics Department, University of Nairobi. It was observed that the current- voltage (I-V) curves obtained for all the measurements for each panel were comparable. The fill factor (FF), short circuit current (Isc), open circuit voltage (Voc), current at maximum power point (Im) and voltage at maximum power point (Vm) were within acceptable margins when compared with the manufacturer’s rated values, an indication of the reliability and accuracy of the method. The method eliminates the need for expensive characterization equipment like solar simulators, unaffordable by many developing country institutions. The experiment is recommended for senior undergraduate students with an interest in renewable energy as one way of introducing them to renewable energy. The experiment may also help in arousing the learner’s interest in solar energy.Item A Test of the Applicability of the Lake Habitat Survey for Hydromorphological Monitoring of a Tropical Alkaline Lake (Simbi) with a Fisheries Potential(International Journal of Fisheries and Aquatic Studies, 2019-09) Opiyo, Stephen; Getabu, Albert Mochache; Sitoki, Lewis Morara; Shitandi, AnakaloThe Lake Habitat Survey (LHS) is an ecological integrity monitoring tool developed for temperate lakes by an independent team of researchers to support the implementation of the EU Water Framework Directive (WFD). It has been widely applied but more testing is needed in different settings, therefore this study investigated the applicability of the LHS protocol in assessing the habitat quality of a tropical alkaline lake in the face of increasing impacts of anthropogenic pressure and climate change. The LHS metrics of Lake Habitat Quality Assessment (LHQA) and Lake Habitat Modification Score (LHMS) estimated for Lake Simbi collectively suggested that the physical habitat quality of the lake is moderate since its hydromorphology is moderately modified. In conclusion, LHS is effective for monitoring ecological condition of water bodies to inform decision making for conservation and management hence it is suitable for adoption in Kenya and the tropics as one of the standard tools for lake environmental assessments.Item A “win-win” scenario: the use of sustainable land management technologies to improve rural livelihoods and combat desertification in semi-arid lands in Kenya(South Eastern Kenya University, 2014) Mganga, Kevin Z.; Musimba, Nashon K. R.; Nyariki, Dickson M.; Nyangito, Moses; Mwang’ombe, Agnes W.Dryland ecosystems support over 2 billion people and are major providers of critical ecosystems goods andservices globally. However, desertification continues to pose a serious threat to the sustainability of the drylandsand livelihoods of communities inhabiting them. The desertification problem is well exemplified in the arid andsemi-arid lands (ASALs) in Kenya which cover approximately 80% of the total land area. This study aimedto 1) determine what agropastoralists attribute to be the causes of desertification in a semi-arid land in Kenya,2) document sustainable land management (SLM) technologies being undertaken to improve livelihoods andcombat desertification, and 3) identify the factors that influence the choice of the sustainable land management(SLM) technologies. Results show that agropastoralists inhabiting the semi-arid lands in southeastern Kenyamainly attribute desertification to the recurrent droughts and low amounts of rainfall. Despite the challengesposed by desertification and climate variability, agropastoralists in the study area are using a combination of SLMtechnologies notably dryland agroforestry using drought tolerant species (indigenous and exotic), grass reseedingusing perennial native and drought tolerant grass species (vegetation reestablishment) and in-situ rainwaterharvesting to improve livelihoods and by extension combat desertification. Interestingly, the choice and adoptionof these SLM technologies is influenced more by the additional benefits the agropastoralists can derive fromthem. Therefore, it is rationale to conclude that success in dryland restoration and combating desertification lies inprograms and technologies that offer a “win-win” scenario to the communities inhabiting the drylands.Item Ab Initio Study of Structural and Vibrational Properties of Fe2P-Type Materials for Near - Room - Temperature Refrigeration(Science and Education publishing (SciEP), 2022-01-23) Thirika, Anne Mwende; Mulwa, Winfred Mueni; Makau, Nicholus Wambua; Ibrahim, Adentuji BamideleThis work has applied density functional theory (DFT) based calculations to investigate the structural and vibrational properties of FeMnP1−xAx (A= Si, Se, Sn and In, x = 0.33) within the first-principles pseudopotential technique. The exchange correlation potentials were treated within generalized gradient approximation (GGA), in the Quantum ESPRESSO code. The Perdew, Burke, Ernzerhof (PBE) functional as implemented in Vanderbilt's ultra-soft pseudo potential (USPP) was used for all the calculations. Vibrational properties were calculated using phonopy code with 1 × 1 × 2 supercell of the conventional unit cell. Thermodynamic properties were predicted using the phonon density of states. The dependence of lattice thermal conductivity on temperature was determined using Debye theory. The optimized structural parameters and corresponding graphical values fit within available experimental data and other theoretical reports. There were no imaginary phonon modes in the phonon dispersion curves revealing that these materials are dynamically stable for magnetic refrigeration.Item Access and utilization of Information resources and services by Water specialists in Kenya: The case of the Ministry of Water and Irrigation(Moi University, 2019) Kariuki, Alice WanjiruEnabling technologies have led to the transformation of libraries and informationcenters‘ collection & services from the traditional prints to e-collections such as e-books, e-journals and other virtual reference services. This has been necessitated bythe environment of increasing economic pressure, rapid shifts in the behaviors andexpectations of the patrons and evolving patterns of scholarly publishing. Thechanges have exerted pressure on libraries and more on the parent institutions in theprovision of the necessary infrastructure and the actual access to e-resources. Thepressure on libraries is in the sourcing, acquisition, repackaging and the provision ofnecessary guidance to end users. Underutilization of these resources may lead to userapathy and affect funding. The aim of the study was to investigate the access and useof e-journals by students and academic staff at USIU and propose strategies forimprovement. The objectives of the study were to: identify the types of e-journaldatabases available in the library; determine the frequency of access and use of e-journals by users; establish the policies in place for governing access to and use of e-journals; examine the level of information and computer literacy skills among userson their access and use of e-journals; establish the degree of awareness of theavailability of e-journals; identify major inhibitors to access and use of e-journals,and suggest measures to enhance access to and use of e-journals. The study wasguided by the Unified Theory of Acceptance and Use of Technology Model byVenkatesh, et al (2003). The study adopted mixed method approach. Stratifiedrandom sampling, simple random sampling and purposive sampling techniques wereused to collect data from students and academic staff. Questionnaires and semi-structured interviews were used to collect data from 202 respondents constituting 186students, 16 academic staff and 4 informants from the library. Collected data wasintegrated, presented and analyzed using qualitative and quantitative techniques ofnarratives and numerical. The major findings of the study were: USIU library has avariety of online research databases hosting online journals that are not adequate andcurrent in meeting the ever-changing information needs of users; the frequency ofaccessing e-journals is relatively low with most users accessing them occasionally;the level of awareness of e-journals and their use is low among the library clientele asmost of them do not go through training prior to access and use e-journals; libraryusers are challenged in their access and use of e-journals by restrictions via InternetProtocol (IP) addresses and slow internet speeds. The study recommends that:librarians develops and offer orientation and training programmes regularly; offercurrent awareness on e-resources; acquire and make available peer reviewed e-journals in support of education and research to meet their needs and institutionalbandwidth bundle as well as providing computer literacy program to cater for lowskill users. The librarians to develop promotional strategies that is blended, integratesand coordinates all communications channels.Item Access to Water in Kenya’s Coast Region: A Challenge to Community Development and Poverty Alleviation in Lamu County(Kenya Aquatica Journal, 2018-11-30) Ignatius, David O.; Hassan, Farida A.; Morara, George N.; Osore, Melckzedeck K.; Mutua, Benedict; Kitaka, Nzula K.Water is considered a basic commodity and essential for life - living on planet earth is dependent on it. However, access to water has been and will continue to be a dilemma for a majority of the residents at the coast of Kenya. A close look at the window on “Coastal Resources and People” reveals that water is a key resource but despite its immense importance, many people especially in the rural areas and the Vulnerable and Marginalized Groups (VMG’s) do not have adequate access to potable, reliable and convenient sources of water. Lamu, currently considered among water scarce counties in Kenya as per the Lamu County Integrated Development Plan (http://lamu.go.ke/wp-content/uploads/2016/03/LAMU_CIDP-Revised.June_2014-1.pdf), faces serious challengeof provision of potable water to its residents. With the influx of people from other parts of the country as a result of the implementation of the Kenya Vision 2030 flagship project - Lamu Port Southern Sudan Ethiopia Transport Corridor (LAPSSET), the current water stresses is only expected to worsen. The Lamu County Government plans to address the ever-increasing demand for access to water but resources to actualise these plans are yet to be consolidated. To complement this situation, Kenya Coastal Development Project (KCDP), a World Bank funded project is working with local communities in Lamu in thedevelopment and implementation of community-led water projects targeting to increasing access to water at household level.This paper will focus on community-based approaches to understand the water-web in Lamu East Sub-County to provide an assessment of opportunities, challenges and sustainability implications. Primary data is used on surveys, Social Assessment (SA) Vulnerable and Marginalised Group Plan (VMGP), observations and recommendations from the Lamu CIDP. It further proposes that of direct usage of saline water, seawater or brackish water, for sanitation purposes could alleviate the freshwater shortage.Item Acoustical properties of compressed earth blocks: Effect of compaction pressure, water hyacinth ash and lime(Elsevier, 2023-07-01) Ouma, Justus; Ongwen, Nicholas; Ogam, Erick; Auma, Mercy; Fellah, Z. E. A.; Mageto, Maxwell; Ben Mansour, Mohamed; Oduor, AndrewThis study assessed the potential use of a mixture of lime and water hyacinth ash (WHA) as binders in fabrication of cylindrical compressed earth blocks (CEBs) with good acoustic absorption properties for building and construction. Different concentrations of the binders and compaction pressures were employed so as to vary the acoustical properties of the fabricated blocks. The geometric and transport parameters of their porous microstructure were recovered through probing using acoustic waves. A low-frequency acoustic wave guide was built for this purpose. It was found out that the transmission coefficient decreased with the compaction pressure, and with addition of lime, while WHA increased the transmission coefficient. The non-acoustical parameters recovered using the equivalent fluid model (JCAL) showed that the variation of the geometry of the microstructure of the blocks is what influences the acoustic transmission coefficient. Thus, the properties of the CEBs can be steered using binder concentration and compaction pressure in a controlled manner.Item Adaptation to climate change impacts on crop water requirements in Kikafu Catchment Tanzania(Journal of Water and Climate Change, 2017) Rotich, Stella; Mulungu, DeogratiasAgricultural activities are the main livelihood for about 70% of Tanzania’s population, with women being the main players. Crops need water (crop water requirements, CWRs) for their growth and production, which can either be rain-fed or irrigation sourced. However, climate change has affected the hydrological cycle, particularly water available for agricultural crops. Since impacts and consequently adaptation are site-specific, an assessment of the effects of climate change on maize water requirements in Kikafu sub-catchment was conducted using a crop simulation model, CROPWAT. Accordingly, climate scenarios were obtained from A2 emission scenario using three general circulation models (GCMs). These scenarios were downscaled at two site locations using the Long Ashton Research Station Weather Generator (LARS-WG) model. The baseline period for the change analysis was 1971–2000. The CWRs are projected to increase by 3.8% in the 2020s and 7.1% in the 2050s at the Moshi Airport and 19.9 and 22.4% at Lyamungu station, respectively. More impact is projected to be during 70–80 days of the development stage and the entire mid-season (81–140 days) whereby the temperature will be high but with low precipitation. With the increasing CWRs, better adaptation measures are increase crop diversification, restore soil organic matter and change cropping systems as established through the multi-criteria analysis.Item Adoption of green energy technologies in selected peri-urban and rural areas of Makueni and Machakos counties, Kenya(World Journal of Research and Review, 2023-05) Muloo, Samson; Kimiti, Jacinta M.; Mwinzi, Muusya; Muthike, GeorgeMany peri-urban and rural households usetraditional stoves which have low energy use efficiency leadingto wasteful use of woodfuel, increase in indoor air pollution andputting more pressure on biomass sources. Energy savingdevices have been introduced which are environmentallyfriendly and economical. The main objective of this study was toassess levels of adoption of green energy technologies in selectedperi-urban and rural areas of Makueni and Machakos Counties,Multistage sampling technique was used whereby; locations andsub-locations were selected purposefully. Households from foursub-locations were chosen using simple random sampling. Atotal of 214 households in the four selected study areas wereinterviewed. The study used questionnaires and interviewschedules for data collection. The collected data was coded andentered into the computer for analysis using the StatisticalPackage for Social Sciences (SPSS) and statistics and datasoftware (STATA) presented using tables. Utilization of metalcharcoal energy device was higher than that of other charcoaldevices in Unoa area (63.1%). Family size had a significanteffect on use of LPG (χ2 = 22.010, P = 0.001) and electric energytechnology (χ2 = 20.482, p = 0.002). The study results on theprediction of future charcoal energy devices adoption showedthat in the next 30 years’ majority of the households will stillprefer Kenya ceramic charcoal stoves to the maendeleo charcoalstoves. The outcome of the research is useful to manystakeholders including the government, Ministries ofAgriculture and Energy, Environmentalists, Market Suppliersof green energy devices and Researchers.