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Articles 511 - 540 of 952
Full-Text Articles in Entire DC Network
Research Methodology Adopted In Developing Tansse-L System, Ellen Kalinga
Research Methodology Adopted In Developing Tansse-L System, Ellen Kalinga
Tanzania Journal of Engineering and Technology (TJET)
Research methodology is among the very important part in a research work. It is the heart which describe the activities necessary for the completion of the research work. Research methodology provides a plan of investigation considered to obtain answers to research problems and it depends on the context of application. This paper presents the research methodology adopted when developing Tanzania Secondary Schools e-Learning (TanSSe-L) system, a learning management system (LMS) which was successfully developed through customization of Moodle open source LMS. TanSSe-L system is a context centered platform for secondary schools in Tanzania. TanSSe-L system was developed using a number …
Material Flow Analysis As A Decision Supporting Tool For Faecal Sludge Resource Recovery: Mathematical Formulation And Quantification, Isabela Thomas Mkude
Material Flow Analysis As A Decision Supporting Tool For Faecal Sludge Resource Recovery: Mathematical Formulation And Quantification, Isabela Thomas Mkude
Tanzania Journal of Engineering and Technology (TJET)
In this work, a conceptual framework for faecal sludge (FS) management and resource recovery in Dar es Salaam city was developed. Material Flow Analysis (MFA) approach was used to assess and quantify the current materials and nutrients to support on decisions for nutrient recovery and minimize environmental pollution in three unplanned settlements of Manzese, Keko and Kipawa in Dar es Salaam city. Nitrogen and Phosphorus were chosen as indicators for the evaluation of the process. The results showed that about 75% of the Dar es Salaam city population relies on pit latrines and 15% connected to septic tanks, translating to …
Assessment Of Surface Water Resources In Great Ruaha River Sub-Basin Tanzania: Application Of Weap Model For Water Allocation And Utilization Impacts Analysis, Deogratias Mulungu
Assessment Of Surface Water Resources In Great Ruaha River Sub-Basin Tanzania: Application Of Weap Model For Water Allocation And Utilization Impacts Analysis, Deogratias Mulungu
Tanzania Journal of Engineering and Technology (TJET)
The Great Ruaha River (GRR) sub-basin is one of the most important waterways in Tanzania as it supports important economic activities. The sub-basin is progressively faced with an inevitable situation of increasing water demand among competing users while the quantity and quality of water is diminishing. The focus of this study was to assess allocation of existing (2012) and future (up to 2025) quantities of surface water in the GRR sub-basin with consideration of priorities given in the Tanzania Water Resources Management Act, 2009 in the order: domestic, environment, agriculture, livestock and non-domestic. Simulation of water allocation scenarios of irrigation …
A Decision-Making Framework For Hybrid Resource Recovery Oriented Wastewater Systems, Nader Rezaei
A Decision-Making Framework For Hybrid Resource Recovery Oriented Wastewater Systems, Nader Rezaei
USF Tampa Graduate Theses and Dissertations
Water shortage, water contamination, and the emerging challenges in sustainable water resources management (e.g., the likely impacts of climate change and population growth) necessitate adopting a reverse logistics approach, which is the process of moving wastewater from its typical final destination back to the water supply chain for reuse purposes. This practice not only reduces the negative impacts of wastewater on the environment, but also provides an alternative to withdrawal from natural water resources, forming a closed-loop water supply chain. However, the design of such a supply chain requires an appropriate sustainability assessment, which simultaneously accounts for economic, environmental, and …
Cyberbullying And Cybervictimization In Tanzanian Secondary Schools: Prevalence And Predictors, Hezron Zacharia Onditi, Jennifer Shapka
Cyberbullying And Cybervictimization In Tanzanian Secondary Schools: Prevalence And Predictors, Hezron Zacharia Onditi, Jennifer Shapka
Journal of Humanities and Social Sciences
This study explored cyberbullying and cybervictimization, and the role of socio demographic and access to technology variables for Tanzanian adolescents. A self-report questionnaire was completed by secondary school students aged 14 to 18 (Form 1 to Form IV). Results provide evidence that online violence is increasingly becoming a problem of concern for Tanzanian adolescents. In particular, whereas 42% of the students reported to have cyberbullied others using electronic communication devices, 58% admitted having experienced cybervictimization. Also, results showed that students who spend more time online, share cellphones with others, and who access digital devices in a private location are more …
Learning Technology By Design: Experiences From In-Service Science And Mathematics Teachers In Tanzania, Ayoub Cherd Kafyulilo,, Frank Tilya
Learning Technology By Design: Experiences From In-Service Science And Mathematics Teachers In Tanzania, Ayoub Cherd Kafyulilo,, Frank Tilya
Journal of Humanities and Social Sciences
This study explored the effectiveness of learning technology by design in the development of in-service science teachers’ competencies of integrating technology in science and mathematics teaching in Tanzania. The learning of technology by design involved a workshop, collaborative design of technology-integrated lessons and classroom teaching. A total of 26 science and mathematics teachers from two selected secondary schools (13 from each) participated in the design of technology-integrated lessons. The study involved pre- and post-intervention assessment of teachers’ technological pedagogical content knowledge (TPACK), which was done through self assessment questions and an observation guide. For the post-intervention assessment, one-to-one interviews were …
The Role Of Self-Efficacy And Use Of Teachers’ Feedback On Students’ Mathematics Performance In Tanzanian Secondary Schools, Florence Kyaruzi
The Role Of Self-Efficacy And Use Of Teachers’ Feedback On Students’ Mathematics Performance In Tanzanian Secondary Schools, Florence Kyaruzi
Journal of Humanities and Social Sciences
Self-efficacy has been found to have positive relationship with important educational variables such as choice of task, persistence, motivation, and academic performance. This study investigated the role of students’ mathematics self-efficacy and use of teachers’ feedback in improving mathematics performance among secondary schools in Tanzania. The study involved 2767 Form III students sampled from 48 secondary schools in Dar es Salaam and Kilimanjaro regions. A questionnaire was used to measure students’ mathematics self-efficacy and mathematics performance, while focus group discussions were used to explore students’ perceptions of the use teachers’ feedback. Data were analysed using structural equation modelling and content …
How ‘Hot’ Is Too Hot? Evaluating Acceptable Outdoor Thermal Comfort Ranges In An Equatorial Urban Park, Su Li Heng, Winston T. L. Chow
How ‘Hot’ Is Too Hot? Evaluating Acceptable Outdoor Thermal Comfort Ranges In An Equatorial Urban Park, Su Li Heng, Winston T. L. Chow
Research Collection School of Social Sciences
Urban green spaces offer vital ecosystem services such as regulating elevated temperatures in cities. Less information exists, however, on how urban green spaces influence outdoor thermal comfort (OTC), which is dependent on people’s perceptions of the complex interactions amongst ambient humidity, wind and both air and radiant temperatures. In this study, we analysed an existing OTC dataset compiled within a large Singapore urban park and calibrated OTC thresholds for physiological equivalent temperatures (PET) by analysing PET against thermal perception survey responses from the park visitors (n = 1508). We examined OTC according to (i) neutral, (ii) acceptable and (iii) preferred …
From Best Fit Technologies To Best Fit Scaling: Incorporating And Evaluating Factors Affecting The Adoption Of Grain Legumes In Sub-Saharan Africa, Andrew Farrow, Esther Ronner, Greta J. Van Den Brand, Stephen K. Boahen, Wilson Leonardo, Endalkachew Wolde-Meskel, Samuel Adjei-Nsiah, Regis Chikowo, Fredrick Baijukya, Peter Ebanyat, Emmanuel A. Sangodele, Jean Marie Sanginga, Speciose Kantengwa, Lloyd Phiphira, Paul Woomer, Theresa Ampadu-Boakye, Edward Baars, Fred Kanampiu, Bernard Vanlauwe, Kenneth E. Giller
From Best Fit Technologies To Best Fit Scaling: Incorporating And Evaluating Factors Affecting The Adoption Of Grain Legumes In Sub-Saharan Africa, Andrew Farrow, Esther Ronner, Greta J. Van Den Brand, Stephen K. Boahen, Wilson Leonardo, Endalkachew Wolde-Meskel, Samuel Adjei-Nsiah, Regis Chikowo, Fredrick Baijukya, Peter Ebanyat, Emmanuel A. Sangodele, Jean Marie Sanginga, Speciose Kantengwa, Lloyd Phiphira, Paul Woomer, Theresa Ampadu-Boakye, Edward Baars, Fred Kanampiu, Bernard Vanlauwe, Kenneth E. Giller
All Peer-Reviewed Publications
The success of scaling out depends on a clear understanding of the factors that affect adoption of grain legumes and account for the dynamism of those factors across heterogeneous contexts of sub-Saharan Africa. We reviewed literature on adoption of grain legumes and other technologies in sub-Saharan Africa and other developing countries. Our review enabled us to define broad factors affecting different components of the scaling out programme of N2Africa and the scales at which those factors were important. We identified three strategies for managing those factors in the N2Africa scaling out programme: (i) testing different technologies and practices; (ii) evaluating …
A Key Note On Performance Of Smoothing Parameterizations In Kernel Density Estimation, Israel U. Siloko, Osayomore Ikpotokin, Edith A. Siloko
A Key Note On Performance Of Smoothing Parameterizations In Kernel Density Estimation, Israel U. Siloko, Osayomore Ikpotokin, Edith A. Siloko
Tanzania Journal of Science
The univariate kernel density estimator requires one smoothing parameter while the bivariate and other higher dimensional kernel density estimatorsdemand more than one smoothing parameter depending on the form of smoothing parameterizations used. The smoothing parameters of the higher dimensional kernels are presented in a matrix form called the smoothing matrix. The two forms of parameterizations frequently used in higher dimensional kernel estimators are diagonal or constrained parameterization and full or unconstrained parameterization. While thefull parameterization has no restrictions, the diagonal hassome form of restrictions.Thestudyinvestigates the performance of smoothing parameterizations of bivariate kernel estimator using asymptotic mean integrated squared error aserror …
Determination Of Radiation Doses To Patients Undergoing Fluoroscopically Guided Orthopaedic Procedures At Muhimbili Orthopaedic Institute In Tanzania, Jacob Busumabu, Ismael N. Makundi, Justin E. Ngaile
Determination Of Radiation Doses To Patients Undergoing Fluoroscopically Guided Orthopaedic Procedures At Muhimbili Orthopaedic Institute In Tanzania, Jacob Busumabu, Ismael N. Makundi, Justin E. Ngaile
Tanzania Journal of Science
The aim of the present study was to determine the magnitude of radiation doses delivered to patients undergoing Fluoroscopically Guided Orthopaedic Procedures (FGOP’s) in Tanzania. The air Kerma Area Product (KAP), fluoroscopy time, organ dose and effective dose to patients undergoing FGOP’s were obtained from Muhimbili Orthopaedic Institute. A total of 72 adult patients from selected three FGOPs namely Lumbar Spine (LS), Dynamic Hip Screw (DHS) and Thoracic Spine (TS) procedures were investigated using C-arm fluoroscopy machine. The knowledge of patient demographic data, radiographic data, KAP and Monte Carlo-based PCXMC software were used to obtain the magnitude of organ doses …
Performance Of A Customized Cryo-Cooling System Designed For The Measurement Of The Lifetime Of Nuclear Excited States At Cryogenic Temperatures, Innocent J. Lugendo
Performance Of A Customized Cryo-Cooling System Designed For The Measurement Of The Lifetime Of Nuclear Excited States At Cryogenic Temperatures, Innocent J. Lugendo
Tanzania Journal of Science
Theoretical predictions that the lifetime of nuclear excited states can be varied if the nucleus is subjected to a condition that allows multiple coherent emission and re-absorption of gamma photons by the nucleus is of much interest to the nuclear physicists. Therefore, an experiment has been designed to study the possibility of lifetime variation. Based on the theory requirements, lifetime variations can be observed when the nucleus is cooled to cryogenic temperatures. Both the cryo-cooling system and the fast timing system have been developed. In the current work, the design, operation and performance of the developed cryo-cooling system is discussed. …
Statistical Analysis Of Ambient Conditions And Water Temperature On Standard Achievement Of Volume Calibration Of Small Laboratory Glassware, Lazaro Revocatus, Nyimvua Shaban, Isambi S. Mbalawata
Statistical Analysis Of Ambient Conditions And Water Temperature On Standard Achievement Of Volume Calibration Of Small Laboratory Glassware, Lazaro Revocatus, Nyimvua Shaban, Isambi S. Mbalawata
Tanzania Journal of Science
Volumetric apparatus calibration is a very sensitive matter in metrological institutions. Identification and evaluation of the uncertainty factors affecting volume calibration of volumetric apparatus such as small laboratory glassware is a critical issue to investigate in order to increase accuracy in calibration.This studyinvestigates the contributions of ambient conditions and water temperature in volume calibration of small laboratory glassware. The study used existing empirical data from the Tanzania Bureau of Standards.The multiple linear regression modelwas used to establish better relationship between explanatory variables and response variable. The model analyzedthree predictor variables namely ambient temperature, pressure and relative humidity. Water temperature was …
Anempirical Performance Comparison Of Meta-Heuristic Algorithms For School Bus Routing Problem, Sherehe Semba, Egbert Mujuni
Anempirical Performance Comparison Of Meta-Heuristic Algorithms For School Bus Routing Problem, Sherehe Semba, Egbert Mujuni
Tanzania Journal of Science
School Bus Routing Problem is an NP-hard Combinatorial Optimization problem. Thus, mega-heuristic algorithms are widely used to solve instances of the School Bus Routing Problem with large data. In this work we present a model of the School Bus Routing Problem and empirical performances comparison between three meta-heuristic algorithms named Simulated Annealing (SA), Tabu Search (TS) and Ant-Colony Optimization (ACO) on the problem. We have analyzed their performances in terms of solution quality. The results show that all three algorithms have the ability to solve the School Bus Routing Problem. In addition, computational results show that TS performed best when …
Status Updates On Plastics Pollution In Aquatic Environment Of Tanzania: Data Availability, Current Challenges And Future Research Needs, Dativa J. Shilla
Status Updates On Plastics Pollution In Aquatic Environment Of Tanzania: Data Availability, Current Challenges And Future Research Needs, Dativa J. Shilla
Tanzania Journal of Science
Plastics are the most useful materials invented by man, and have brought great convenience to our daily lives but not without problems. Inappropriate disposal of wasted plastics has caused serious environmental problems. Over the past decade, microplastic debris in both marine and freshwater systems have become an emerging issue. A literature review was conducted to summarize the current state of knowledge of plastic pollution in Tanzanian aquatic systems. Although, Tanzania has vast coastlines and world’s largest freshwater lakes, the extent of microplastics presence in the aquatic environment remains largely unreported. Data from volunteer beach cleanups in Dar es Salaam areas …
A Key Note On Performance Of Smoothing Parameterizations In Kernel Density Estimation, Israel U. Siloko, Osayomore Ikpotokin, Edith A. Siloko
A Key Note On Performance Of Smoothing Parameterizations In Kernel Density Estimation, Israel U. Siloko, Osayomore Ikpotokin, Edith A. Siloko
Tanzania Journal of Science
The univariate kernel density estimator requires one smoothing parameter while the bivariate and other higher dimensional kernel density estimatorsdemand more than one smoothing parameter depending on the form of smoothing parameterizations used. The smoothing parameters of the higher dimensional kernels are presented in a matrix form called the smoothing matrix. The two forms of parameterizations frequently used in higher dimensional kernel estimators are diagonal or constrained parameterization and full or unconstrained parameterization. While thefull parameterization has no restrictions, the diagonal hassome form of restrictions.Thestudyinvestigates the performance of smoothing parameterizations of bivariate kernel estimator using asymptotic mean integrated squared error aserror …
Construction Of A High Temperature (~ 200 °C) Oil Pump For Solar Thermal Energy Storage System For Cooking Applications, Jimmy Chaciga, Nyeinga Karidewa, Denis Okello, Benard Tabu
Construction Of A High Temperature (~ 200 °C) Oil Pump For Solar Thermal Energy Storage System For Cooking Applications, Jimmy Chaciga, Nyeinga Karidewa, Denis Okello, Benard Tabu
Tanzania Journal of Science
In this study, a positive displacement (PD) oil pump capable of operating at temperatures about 200 °C was constructed using locally available materials. The oil pump was tested to circulate pre-heated refined sunflower oil in Thermal Energy Storage (TES) tank comprising of an oil only and rock pebble-oil system and cooking application. The oil pump was constructed of harden steel and mild steel materials driven by AC/DC electric motor rated 8000 rpm. Standard gear teeth cutting tool was employed to produce the spurs and the pumps’ speed was varied using variable AC transformer connected to 220V AC main source. The …
Electrophoretic Deposition Of Tio2 Thin Films For Photocatalytic Degradation Of Organic Pollutants In Water, Francis W Nyongesa, Bernard O Aduda, Wilson G Nyaga
Electrophoretic Deposition Of Tio2 Thin Films For Photocatalytic Degradation Of Organic Pollutants In Water, Francis W Nyongesa, Bernard O Aduda, Wilson G Nyaga
Tanzania Journal of Science
In this study, electrophoretic deposition (EPD) technique was used to deposit titanium dioxide (TiO2) thin films on conducting glass substrates for application in photocatalytic degradation of organic pollutants in water. Phenol was used as a model pollutant. The EPD suspension related parameters and deposition conditions were first optimized for good quality film deposits. The suspension stability and deposition conditions that result in good adherence of TiO2 particles to the substrate with homogeneous film coatings are ethanol, a TiO2 solid loading of 4 wt%, a 0.2 wt% iodine concentration in the solvent and a deposition voltage of 20 V in a …
Effects Of Aluminium And Tungsten Co-Doping On The Optical Properties Of Vo2 Based Thin Films, Cephas J Lyobha, Nuru R Mlyuka, Margaret E Samiji
Effects Of Aluminium And Tungsten Co-Doping On The Optical Properties Of Vo2 Based Thin Films, Cephas J Lyobha, Nuru R Mlyuka, Margaret E Samiji
Tanzania Journal of Science
Aluminium and tungsten co-doped vanadium dioxide (VO2:W:Al) thin films were deposited by DC reactive magnetron sputtering technique. In this work we report on the effects of aluminium and tungsten co–doping on the optical properties of vanadium dioxide (VO2) based thin films with a view of combining both increased luminous transmittance (Tlum) and lowered transition temperature (τc). The effect of aluminium and tungsten co-doping on semiconductor-metal transition of vanadium dioxide films was investigated and compared with tungsten doped and undopedVO2films. Spectral transmittances of the films were obtained using Shimadzu SolidSpec-3700 DUV UV-VIS-NIR spectrophotometer. The results revealed that the transmittance of tungsten …
Hall Effect Parameters Of Aluminium And Tungsten Co-Doped Vo2 Thin Films, Mohamed Mussa, Nuru R Mlyuka, Margaret E Samiji
Hall Effect Parameters Of Aluminium And Tungsten Co-Doped Vo2 Thin Films, Mohamed Mussa, Nuru R Mlyuka, Margaret E Samiji
Tanzania Journal of Science
The Hall Effect parameters of Al and W co-doped VO2 thin films were studied in order to explain the effect of co-doping on the electrical properties of thermochromic VO2 films. The carrier concentrations and conductivity of the films were found to increase with increase in temperature while carrier mobility decreased reaching a minimum around the transition temperature then slightly rose and became stable at high temperatures. Tungsten doped films displayed higher carrier concentrations and conductivity on both sides of the metal insulator transition and lower mobility compared to undoped and Al and W co-doped VO2 thin films.
Effects Of Selenized Dc Sputtered Precursor Stacking Orders On The Properties Of Cu2znsnse4 Absorber Layer For Thin Film Solar Cells, Hezekiah B Sawa, Margaret E Samiji, Nuru R Mlyuka
Effects Of Selenized Dc Sputtered Precursor Stacking Orders On The Properties Of Cu2znsnse4 Absorber Layer For Thin Film Solar Cells, Hezekiah B Sawa, Margaret E Samiji, Nuru R Mlyuka
Tanzania Journal of Science
This study investigated the effects of selenized DC sputtered precursor stacking orders on the structural, electrical and optical properties of copper zinc tin selenide (CZTSe) absorber layer for thin film solar cells. The precursors were deposited sequentially on the soda lime glass substrate at room temperature by DC magnetron sputtering. The precursors were selenized by annealing in an atmosphere containing selenium pellets and nitrogen gas. The structural, morphological, optical and electrical properties were respectively characterized using X-Ray Diffractometer (XRD), atomic force microscopy (AFM), UV/VIS/NIR lambda 9/19 spectrophotometer, Hall Effect measurement system (HMS 3000) and a four point probe system. CZTSe …
Optimization Of Zinc To Tin Ratio In A Sol Gel Precursor Solution On The Growth And Properties Of Annealed Czts Thin Films, Justine John Tibaijuka, Margaret E Samiji, Nuru R Mlyuka
Optimization Of Zinc To Tin Ratio In A Sol Gel Precursor Solution On The Growth And Properties Of Annealed Czts Thin Films, Justine John Tibaijuka, Margaret E Samiji, Nuru R Mlyuka
Tanzania Journal of Science
CZTS thin films were deposited by sol–gel spin coating method using precursor solutions prepared by dissolving copper acetate dihydrate, zinc acetate dihydrate, tin chloride and thiourea in methanol and monoethylamine then annealed in RTP furnace at 500 °C. Sol–gel precursor solutions were prepared with different Zn/Sn in a precursor solution and were annealed at different time intervals; and their effects on the optical and electrical properties of CZTS (Cu2ZnSnS4) films were investigated. The optical band-gap values were estimated to be between 1.30 and 1.88 eV while the absorption coefficients were in the range of 104 cm–1 in the visible region. …
Compositional And Thickness Effects On The Optical Properties Of Zinc–Doped Selenium–Antimony Thin Films, Austine A Mulama, Julius M Mwabora, Andrew O Oduor, Cosmas M Muiva
Compositional And Thickness Effects On The Optical Properties Of Zinc–Doped Selenium–Antimony Thin Films, Austine A Mulama, Julius M Mwabora, Andrew O Oduor, Cosmas M Muiva
Tanzania Journal of Science
Chalcogenide system of antimony (Sb)-selenium (Se)-zinc (Zn) system is a promising semiconductor for phase change memory devices due to its thermal stability and low power consumption. The study investigated the effect of film thickness and zinc content on the optical properties of thermally evaporated Sb10Se90-xZnx (x = 0, 5, 10 & 15 at. %) thin films. It was found that transmittance (T~ 85-40%) and optical band gap energy (Eopt ~ 1.60 eV – 1.22 eV) decreased but absorption coefficient (α~0.840–2.031 104 cm–1) increased with increase in zinc content. Furthermore, as the film thickness increased from 53 ± 5 nm to …
Effects Of Thickness Variation In The Multilayer Thin Film On The Performance Of Eta Solar Cell, Robinson J Musembi
Effects Of Thickness Variation In The Multilayer Thin Film On The Performance Of Eta Solar Cell, Robinson J Musembi
Tanzania Journal of Science
A highly structured eta solar cell of the type TiO2/In(OH)xSy/Pb(OH)xSy/PEDOT:PSS/Au with different layer thickness has been fabricated using various deposition techniques for each layer in the stack. The solar cell parameters, Uoc, FF and have been extracted from current- voltage characteristics measurements. The buffer layer and the hole collector layer have been kept constant while the window and the absorber layer have been varied. The thickness of either of the two layers being varied has been observed to affect the performance of the solar cells. The difference in thickness has been attributed to affect the charge lifetime in the space …
Thermal Performance Of Selected Oils In Uganda For Indirect Solar Domestic Cooking Applications, Benard Tabu, Karidewa Nyeinga, Jimmy Chaciga, Denis Okello
Thermal Performance Of Selected Oils In Uganda For Indirect Solar Domestic Cooking Applications, Benard Tabu, Karidewa Nyeinga, Jimmy Chaciga, Denis Okello
Tanzania Journal of Science
This study experimentally evaluated the thermal performance of selected oils in Uganda for indirect solar domestic cooking applications. The oil samples used were refined sunflower oil, refined palm oil and thermia B. These oils are locally available in Uganda. Thermal stratification, energy and exergy analysis were performed for each oil to determine their suitability for Thermal Energy Storage (TES) using a thermosiphon principle. The results showed that thermal stratification of refined sunflower oil was higher as compared to refined palm oil and thermia B during the first one hour. The stored energy and exergy for refined sunflower oil was generally …
Effects Of Substrate Radial-Position Relative To The Sputter-Gun Axis On The Electrical, Optical And Structural Properties Of Zno Thin Films Deposited By Reactive Direct Current Magnetron Sputtering, John Paul Eneku, Tom Otiti, Julius Mwakondo Mwabora, David Horwat
Effects Of Substrate Radial-Position Relative To The Sputter-Gun Axis On The Electrical, Optical And Structural Properties Of Zno Thin Films Deposited By Reactive Direct Current Magnetron Sputtering, John Paul Eneku, Tom Otiti, Julius Mwakondo Mwabora, David Horwat
Tanzania Journal of Science
ZnO thin films were deposited using reactive direct current (dc) magnetron sputtering on glass substrates placed at seven variable radial positions (-1, 0, 1, 2, 3, 4 and 5 cm) relative to the sputter-gun (target) axis. A pure zinc target was used and sputtering carried out in argon and oxygen atmosphere with flow rates of 50 sccm and 6 sccm, respectively. XRD characterization showed that, all films crystallized homogeneously in the wurtzite phase with a strong (002) and a weak (004) orientations. Film crystallinity was very low at substrate positions located less than or equal to 1 cm from the …
Community Forestry Frameworks In Sub-Saharan Africa And The Impact On Sustainable Development, Lalisa A. Duguma, Joanes Atela, Alemayehu N. Ayana, Dieudonne Alemagi, Mathew Mpanda, Moses Nyago, Peter A. Minang, Judith M. Nzyoka, Divine Foundjem-Tita, Cécile Ngo Ntamag-Ndjebet
Community Forestry Frameworks In Sub-Saharan Africa And The Impact On Sustainable Development, Lalisa A. Duguma, Joanes Atela, Alemayehu N. Ayana, Dieudonne Alemagi, Mathew Mpanda, Moses Nyago, Peter A. Minang, Judith M. Nzyoka, Divine Foundjem-Tita, Cécile Ngo Ntamag-Ndjebet
All Peer-Reviewed Publications
Community based forest management (CBFM) has been implemented in Africa since the 1980s. Three main objectives, which are currently part of the sustainable development goals (SDGs), underlie the formation of CBFM. They are (1) enhancing community engagement in forest management, (2) reducing rural poverty, and (3) promoting forest resources conservation. We examine CBFM frameworks in sub-Saharan Africa (SSA) and CBFM schemes’ contribution to selected sustainable development goals relevant to the forestry sector. Five SSA countries, Ethiopia, Kenya, Cameroon, Uganda, and Tanzania were chosen for the study because of their long-term engagement in CBFM. The analysis was based on desk review …
A Catalog Of Orchid Species And Their Distribution In Mazumbai Forest Reserve, Tanga Region, Tanzania, Sierra Loomis
A Catalog Of Orchid Species And Their Distribution In Mazumbai Forest Reserve, Tanga Region, Tanzania, Sierra Loomis
Independent Study Project (ISP) Collection
Although orchids are common in Mazumbai Forest Reserve (MFR), there are limited resources on where they grow and how to identify them. The primary objective of this study is to create an updated catalog of orchids in MFR, using species abundance, richness and diversity of the orchids as indicators of where orchids prefer to grow in MFR. Orchid species vary greatly as altitude changes, making it important to survey orchids across different altitudes. Therefore, Mazumbai Forest was split into five different altitudinal bands spanning 1400 – 1900m and six 100 x 20m plots in each band were surveyed for both …
Livelihoods Of The People Of Mazumbai: A Collection Of Stories And Portraits, Tanga Region, Tanzania, Joseph Baldus
Livelihoods Of The People Of Mazumbai: A Collection Of Stories And Portraits, Tanga Region, Tanzania, Joseph Baldus
Independent Study Project (ISP) Collection
Despite rapid urbanization in Tanzania, agriculture remains central to the nation, the economy, and the livelihoods of a large portion of the population. Smallholder farmers account for the vast majority of agricultural production, yet are an extremely vulnerable population due to poverty, single-sourced income, and climate-dependency for both subsistence and cash-crop agriculture (Rapsomanikis, 2015). This report explores these dynamic rural livelihoods through interviews and portrait photographs in a case study on Mazumbai, Tanga region, Tanzania. Semi-structured interviews explore the people’s modes of economic subsistence, domestic lives, education, challenges, and life stories. Excerpts from these interviews combined with portrait photographs create …
Cultivating Third Party Development In Platform-Centric Software Ecosystems: Extended Boundary Resources Model, Brown C. Msiska
Cultivating Third Party Development In Platform-Centric Software Ecosystems: Extended Boundary Resources Model, Brown C. Msiska
The African Journal of Information Systems
Software ecosystems provide an effective way through which software solutions can be constructed by composing software components, typically applications, developed by internal and external developers on top of a software platform. Third party development increases the potential of a software ecosystem to effectively and quickly respond to context-specific software requirements. The boundary resources model gives a theoretical account for cultivation of third party development premised on the role of platform boundary resources such as application programming interfaces (API). However, from a longitudinal case study of the DHIS2 software ecosystem, this paper observes that no matter how good the boundary resources …