College of Natural and Applied Sciences

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5G network slicing using SDN and NFV: A survey of taxonomy, architectures and future challenges
(Elsevier, 2019-11) Barakabitze, Alcardo Alex; Ahmad, Arslan; Mijumbi, Rashid; Hines, Andrew
The increasing consumption of multimedia services and the demand of high-quality services from cus- tomers has triggered a fundamental change in how we administer networks in terms of abstraction, sep- aration, and mapping of forwarding, control and management aspects of services. The industry and the academia are embracing 5G as the future network capable to support next generation vertical appli- cations with different service requirements. To realize this vision in 5G network, the physical network has to be sliced into multiple isolated logical networks of varying sizes and structures which are ded- icated to different types of services based on their requirements with different characteristics and re- quirements (e.g., a slice for massive IoT devices, smartphones or autonomous cars, etc.). Softwarization using Software-Defined Networking (SDN) and Network Function Virtualization (NFV)in 5G networks are expected to fill the void of programmable control and management of network resources. In this paper, we provide a comprehensive review and updated solutions related to 5G network slicing us- ing SDN and NFV. Firstly, we present 5G service quality and business requirements followed by a descrip- tion of 5G network softwarization and slicing paradigms including essential concepts, history and differ- ent use cases. Secondly, we provide a tutorial of 5G network slicing technology enablers including SDN, NFV, MEC, cloud/Fog computing, network hypervisors, virtual machines & containers. Thidly, we compre- hensively survey different industrial initiatives and projects that are pushing forward the adoption of SDN and NFV in accelerating 5G network slicing. A comparison of various 5G architectural approaches in terms of practical implementations, technology adoptions and deployment strategies is presented. Moreover, we provide a discussion on various open source orchestrators and proof of concepts representing industrial contribution. The work also investigates the standardization efforts in 5G networks regarding network slicing and softwarization. Additionally, the article presents the management and orchestration of net- work slices in a single domain followed by a comprehensive survey of management and orchestration approaches in 5G network slicing across multiple domains while supporting multiple tenants. Further- more, we highlight the future challenges and research directions regarding network softwarization and slicing using SDN and NFV in 5G networks.
A bibliometric analysis of human-wildlife conflicts in East Africa
(IJCS, 2022) Mnzava, Ester Ernest; Sirima, Agnes Anthony
Literature appraisal reveals a sufficient number of studies (research productivity), which have been conducted in the field of human-wildlife conflicts. However, little is known about the evolution of knowledge generation in the field, trends in research output, countries of publication, and international collaborations and specifically statistical related data. To track research productivity of human-wildlife conflict in East Africa, the study examines literature growth, describes the country-wise production of literature and establishes the degree of collaboration by studying authorship patterns on human-wildlife conflicts for the last 20 years. Publish or Perish software was used, followed by the execution of the search via Google scholar database on 28 March 2019. Regarding the country-wise contribution of literature, Tanzania was found to contribute 46 (32.2%), Uganda 45 (31.5%), Kenya 44 (30.8%) and Rwanda 8 (5.6%) and none from Burundi and South Sudan. The overall research productivity in the field of human-wildlife conflicts for Tanzania, Kenya, Uganda and Rwanda is increasing. This study provides a fairly accurate representation of research productivity on human-wildlife conflicts in East Africa from Google scholar database.
A bibliometric analysis of the Tanzania journal of agricultural science (1998-2017)
(Libraries at University of Nebraska-Lincoln, 2019) Chirwa, Mussa Ndambile; Mnzava, Ester
The term bibliometrics was first coined by Pritchard in 1969. From there on different people defined and interpreted bibliometrics in various ways. For instance, British Standards Institution, (1976) define bibliometrics as the use of mathematical and statistical methods to study documents and patterns of publication. One year later Hawkins (1977) interpreted bibliometrics to mean the “quantitative analysis of the bibliographic features of a body of literature”. Historically, the term “librametry” was firstly used as coined by S.R. Ranganathan to refer quantitative study of librarianship. Bibliometrics is analogous to Ranganathan’s librametrics and the Russian concept scientometrics (Thanuskodi, 2010).
A HPLC-MS/MS method for screening of selected antibiotic adulterants in herbal drugs
(The Royal Society of Chemistry, 2022) Mwankuna Christopher Johnson; Uwamaliya Grâce Ange; Mariki Eliapenda Elisante; Mabiki Faith; Malebo Hamisi M.; Mdegela Robinson; Styrishaveb Bjarne
The use of herbal products adulterated with conventional drugs increases the risk of developing microbial resistance and causes herb-to-drug interaction, leading to severe clinical consequences. The complex nature of herbal products has been a challenge for the unambiguous identification of adulterants. The improved analytical selectivity and sensitivity of hyphenated techniques such as high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) enable the confirmatory screening of adulterants in herbal products. Simultaneous screening of adulterants is necessary and efficient because it has been established that more than one chemical adulterant may be present in one herbal product. An HPLC-MS/MS method for the simultaneous detection and quantification of amoxicillin, ampicillin, metronidazole, ciprofloxacin, sulfamethoxazole, and trimethoprim in powdered herbal drugs was developed. Deuterated metronidazole-d3, trimethoprim-d3, ciprofloxacin-d8, and sulfamethoxazole-d4 were used as internal standards (ISs). For each analyte, two transitions were monitored using protonated molecules as precursor ions. The extraction of analytes from herbal products was performed using a simple methanol : water : formic acid (90 : 10 : 0.05, v/v) extraction solvent. Chromatographic separation was done in a gradient of 0.01% formic acid in methanol and 0.01% formic acid in MilliQ water. The calibration curves were linear (r2 $ 0.996) over the range of 0.005–2.5 mg mL 1 for all compounds except metronidazole, whose range was 0.005–1 mg mL 1. The limit of detection (LOD) ranged from 0.012 to 0.046 mg mL 1, while the limit of quantification (LOQ) ranged from 0.066 to 0.153 mg mL 1. The accuracy, expressed as the recovery of spiked herbal products, ranged from 45% to 114%. The precision, expressed as relative standard deviation (RSD) at two concentration levels, ranged from 1.6% to 15.9%. The matrix effect expressed as the matrix factor (MF) ranged from 0.79 to 0.92. The developed method was applied to powder herbal products purchased in Tanzania. Amoxicillin, ampicillin, trimethoprim, sulfamethoxazole, and ciprofloxacin were not detected in all samples. Metronidazole was detected in eight samples with the highest concentration of 1.38 mg g 1. The developed method is suitable for the detection of all the studied antibiotic adulterants in herbal products. Quantification can be performed for all the compounds except ciprofloxacin due to its lower recovery.
A new ellagic acid rhamnoside and other biologically active compounds from roots and stems of Synadenium Glaucescens pax
(Sokoine University of Agriculture, 2023-05) Rwegoshora Frank
Medicinal plants have been used as a source of drugs and drug templates. The extracts of Synadenium glaucescens Pax (SG) from roots and stems contain bioactive secondary metabolites against bacterial and viral infections. However, majority of its pure compounds were uncharacterized and their phytochemical profiles in different phytogeographical regions were unknown. Therefore, this study aimed at characterization of more compounds which are promising drug leads. Furthermore, the study investigated the phytochemical profiles of SG from three regions of Tanzania. Samples of SG were collected from Njombe, Morogoro and Tanga regions as representatives of three phytogeographical zones of Tanzania. All sample were dried in a cold and dark room between 15 to 18 oC at the Tanzania Tree Seed Agency-Morogoro. Samples were pulverized using a laboratory milling machine (Christy Hunt Engineering Ltd, England) to afford approximately 1 mm particles’ size. The isolation of pure compounds involved root barks and stem barks of SG from Njombe. Phytochemical profiling involved five parts (root barks, root wood, stem barks, stem wood and leaves). Sample extraction was done by total maceration using either methanol or ethanol. Fractionation of the crude extracts was done through vacuum Liquid chromatography in solvent gradient systems from Hexane, ethyl acetate/ dichloromethane and finally methanol/ ethanol. Concentration of extracts was done using rotary evaporator at <60 oC. Isolation of pure compounds was done by column chromatography in a solvent gradient system. A single spot on the thin layer chromatography plate in both treatments was an indicator for a pure compound. Structures of compounds were elucidated through (1D and 2D) of a 600 MHz Bruker Avance III HD nuclear magnetic resonance (NMR) machine. Confirmation of structures involved LC/GCMS, FTMS-ESI, NIST library and in comparison, to the literature. The SciFinder database was used for reference of a new compound. The processing NMR spectral data was performed using Bruker TopSpin 3.6.2 while compound structures were drawn in ChemDraw Professional 16.0. Biological activities involved cytotoxicity and antibacterial tests of pure compounds. Cytotoxicity studies were done using Brine shrimp assay involving Artemia salina cysts which were hatched and used within 24 hours of incubation. The varying concentrations (2400- ȝJ PO LQ P/ RI % v/v DMSO were employed in duplicate. 7KH FRPSRXQGV¶ concentration killing 50 % of the nauplii larvae was determined. An In vitro antibacterial efficacy of pure compounds was done by using microtitre plate assay. Four standard strains of bacteria were used (Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC51559, Escherichia coli ATCC25922 and Pseudomonas aeruginosa ATCC 27853. The activities of the compounds were evaluated using the observed MIC values. Determination of the phytochemical profiles on the thin layer FKURPDWRJUDSK\ SODWHV XVHG DQ RSWLPDO ȝ/ YROXPH RI mg/mL. The number of compounds were recorded at 254nm, 365nm of an ultraviolet lamp and after colour reaction. Data from the thin layer chromatography were analysed in JMP statistical software. A total of fifteen (15) compounds were isolated and elucidated. A new ellagic acid rhamnoside 3',4'-di-O- methylellagic acid-4-Į-L-rhamnopyranoside, 28 mg (32) was isolated as greyish powder. it showed high res. FTMS-ESI- of 476.0921 and melting point of 251.0~ 252.7 oC. Other known phenolics 3,4,3'-tri-O-methylellagic acid, 14 mg (33), hemicosanylferulate,65 mg (34) and octacosylferulate, 19 mg (35) were also isolated. The study also led to isolation of two hydrocarbons from the root barks: 1-nonacosene, 11 mg (38), and hexacosane,173 mg (39) and one fatty acid from the stem barks; hexacosanoic acid, 26 mg (40). The isolated triterpenoids include Lupeol, 65 mg (18) from the stem barks, euphol, 1855.5 mg (28) from both roots and stem barks, epifriedelanol, 167 mg (36) from both roots and stem barks and a steroid ȕ-sitosterol 64 mg (30) from the root barks. Cytotoxicity tests indicated that all the tested compounds were non-toxic (LC50 ! ȝJ P/) up to a maximum tested FRQFHQWUDWLRQ RI ȝJ P/ Octacosylferulate demonstrated strong activity against S. aureus (MIC= 0.125 mg/mL) Phytochemical screening by TLC indicated a significant variation in concentration and distribution of compounds in SG among the three regions (p< 0.0001). Njombe registered the highest number of compounds (mean= 12.4000) while Morogoro had the least of all (mean= 9.7000). Euphol, a triterpenoid in root barks was detected to be at the highest concentration in Tanga and the lowest in Morogoro. Derivatives of ellagic acid were detected in root barks at all ages and locations. The results also indicated continuous disappearance of red fluorescing compounds in stems barks and leaves as the plant age increased. The number of compounds increased with age while the optimal age for a maximum number of phytochemicals was 3 to 4.5 years. Furthermore, the stem barks registered the highest number of phytochemicals (>15). A new compound: 3',4'-di-O-methylellagic acid-4-Į-L- rhamnopyranoside along with 14 other known compounds were isolated from root and stem barks of SG. The isolated compounds during this study represent six major groups of secondary metabolites of pharmacological importance which are Phenolics, triterpenoids, steroids, long chain hydrocarbons, long chain amine and Fatty acids. This new compound is suggested to serve as a marker for standardization and quality control of any formulation from the root barks of S. glaucescens Pax.
A novel qoe-aware sdn-enabled, nfv-based management architecture for future multimedia applications on 5g systems
(2019) Barakabitze,Alcardo Alex; Sun,Lingfen; Mkwawa,Is-Haka; Ifeachor,Emmanuel
This paper proposes a novel QoE-aware SDN enabled NFV architecture for controlling and managing Future Multimedia Applications on 5G systems. The aim is to improve the QoE of the delivered multimedia services through the fulfilment of personalized QoE application requirements. This novel approach provides some new features, functionalities, concepts and opportunities for overcoming the key QoE provisioning limitations in current 4G systems such as increased network management complexity and inability to adapt dynamically to changing application, network transmission/traffic or end-user’s demand
A study of data sources for accessibility and reuse practices among agricultural researchers in Tanzania
(Journal of Agricultural & Food Information, 2023-03-10) Mwinami, Nolasko Victory; Dulle, Frankwell W.; Mtega, Wulystan Pius
This paper reports a study that investigated how agricultural researchers use and reuse other researchers’ data in Tanzania. This research used a survey method to investigate the factors influencing researchers in this use/reuse. Findings indicated that more than 80% of researchers use and reuse data accessed from different sources. Several factors influence the majority of researchers (more than 70%) to use and reuse data. The results of this study may attract the attention of agricultural researchers elsewhere to agricultural data use and reuse practices.
Ability of form four students on food test laboratory practicals in the selected secondary schools in Tanzania
(AQUADEMIA, 2022) Jamal, Jumanne Athuman
This study sought to assess the understanding of form four students on food test practical in the selected secondary schools in Morogoro Municipality, Tanzania. Food test is one of the fundamental skills to be acquired by biology secondary education students. The study involved 252 form four students in from four secondary schools within the vicinity of Morogoro Municipality. Data collection was done by the researcher during teaching practice assessment period, June to July 2022 using food test practical test. The test of 35 items was constructed and validated by the researcher. The overall mean score was 12.0 (34.1%) means that on overage selected students have a “D” class, which means poor knowledge level on food test. An analysis of independent samples t-test based on sex at α=0.05 produced a ρ of 0.233 and a t-value of 0.373, hence failed to reject the null hypothesis. To have a broader understanding of students’ ability on food test laboratory practicals and attempt generalization through replication of findings, it is advised that a second study with larger samples across the country be conducted.
Ability of form four students on food test laboratory practicals In the selected secondary schools in Tanzania
(AQUADEMIA, 2022-06) Athuman, Jamal Jumanne
This study sought to assess the understanding of form four students on food test practical in the selected secondary schools in Morogoro Municipality, Tanzania. Food test is one of the fundamental skills to be acquired by biology secondary education students. The study involved 252 form four students in from four secondary schools within the vicinity of Morogoro Municipality. Data collection was done by the researcher during teaching practice assessment period, June to July 2022 using food test practical test. The test of 35 items was constructed and validated by the researcher. The overall mean score was 12.0 (34.1%) means that on overage selected students have a “D” class, which means poor knowledge level on food test. An analysis of independent samples t-test based on sex at α=0.05 produced a ρ of 0.233 and a t-value of 0.373, hence failed to reject the null hypothesis. To have a broader understanding of students’ ability on food test laboratory practicals and attempt generalization through replication of findings, it is advised that a second study with larger samples across the country be conducted.
Access and use of agricultural market information by smallholder farmers: measuring informational capabilities
(John Wiley & Sons Ltd, 2019) Magesa, Mawazo M; Michael, Kisangiri; Ko, Jesuk
While farmers sell their crops, middlemen provide a linkage between them, markets and buyers. Middlemen have good knowledge of working conditions of markets and have access to agricultural market information. Due to poor access to markets and agricultural market information by smallholders, there is a feeling that middlemen benefit more while farmers sell their crops. Good access to markets and market infor- mation may help farmers bypass middlemen while selling crops and thus benefit more. Thus, it is best to improve the informational capabilities (ICs) of farmers in agri- cultural marketing. Thus, this research measured ICs of farmers accessing market information, through a program NINAYO, while selling their crops. The research uti- lized the informational, psychological, social, and economic dimensions of the empowerment framework in identifying capability indicators to formulate survey questions. Data were collected from smallholders in six regions in Tanzania. The anal- ysis utilized measures of life satisfaction and results showed that about half of the variation in the dependent variable, satisfaction with capabilities, was explained by the model. Backward elimination analysis confirmed that life satisfaction is multi- dimensional. Robustness test confirmed a positive relationship between satisfaction and capabilities. Overall, results confirmed ICs are multidimensions, their improve- ment empowers farmers in agricultural marketing.
Accessibility and use of nutrition information in addressing under five child malnutrition in Morogoro urban, Tanzania
(Sokoine University of Agriculture, 2002) Chilimo,Wanyenda Leonard
This study was undertaken to examine the access to and use of nutrition information in addressing the problem of malnutrition in Morogoro urban district Tanzania. The study investigated the Maternal and Child Health clinics (MCH) nutrition information delivery systems; variables that determine accessibility and use of information; extent of the use of nutrition information in addressing malnutrition and the relationship between the information that mothers have and the nutritional status of their children. Survey research method was used for data collection whereby questionnaires and face-to-face interviews were used for collecting data. The study found that although the MCH health and nutrition education sessions arc an important aspect in disseminating nutrition information to mothers, these sessions are seldom conducted and the attendance of mothers to these sessions is poor; awareness of mothers concerning different nutritional aspects is still low due to lack of information; and education is the most important variable that determines use and access to nutrition information.
Accessibility of women to health information in Tanzania: A case study of Morogoro Region
(Emerald Publishing Limited, 2017-05) Benard, Ronald; Chipungahelo, Monica Samwel
Purpose – The aim of this study is to examine accessibility of health information to women in Tanzania with reference to the Morogoro region. The specific objectives of the study were: first, to identify the health information needs of women; second, to determine the accessibility of the needed health information to women in the study area; and third, to determine the preferred sources of information used by women in accessing health information in the study area. Design/methodology/approach – A descriptive survey method – cross-sectional design – was used. Semi-structured questionnaires with both open- and close-ended questions were used to collect data from four wards of Morogoro Municipal Council, Tanzania. Key informant interviews were conducted with 12 women from four wards, 3 women were selected from each ward. Findings – The findings also indicated that there was a significant relationship between wards and accessibility to certain types of information which were concerning hypertension, family planning, malaria and typhoid. Although information on diabetes and hypertension had lower percentages of accessibility in all four wards, the study findings revealed that medical doctors, pharmacy shops and family were the main sources of information used by women to access health information. Radio and television were rated as preferred sources of information required by women, whereas internet, local herb hawkers and mobile phones were rated as non-preferable. It is therefore recommended that the government through health-care providers and medical librarians should be proactive in creating awareness and disseminate health information on non- communicable diseases such as hypertension and diabetes to women. Practical implications – This paper provides practical recommendations on how to improve accessibility of health information in the communities. Social implications – The paper has an implication of improving accessibility of health information to women in the communities. Originality/value – The paper provides appropriate knowledge that is needed in improving access to health information in Tanzanian communities and in other developing countries communities
Accumulation of SOC in relatively undisturbed tropical mountain foothills under climate change scenarios: the case of Uluguru mountain, Tanzania
(Saudi Society for Geosciences and Springer Nature Switzerland AG, 2023-07-01) Mkonda, Msafiri Y.; Minja, Gileard S.; Ligate, Elly J.; Kaganga, Laison S.; Haule, Tiemo R.; Msemwa, Ubaya S.
Soil nutrients form an important part of agro-ecosystems in various landscapes, including mountainous areas. Most foothills in tropical mountains are heterogeneous in terms of the accumulation of soil nutrients due climatic location and ecological endowments. Since most mountain foothills have potential for the provision of environmental services, it is imperative to assess the salient soil nutrients including carbon in order to determine the amount. This study assessed the accumulation of soil organic carbon (SOC) in the relatively undisturbed foothills of Uluguru Mountains whose geology indicates that they were formed during cretaceous age (i.e. ≈50 million years ago). The study also determined the trends of rainfall and temperature because these elements of climate have important influence on carbon accumulation. In conducting this study, we sampled Kiroka Village (in Kiroka Ward) because it is found at the foothills of the Uluguru Mountain and most of its parts are relatively undisturbed. In this place, sixteen soil sampling points were established within one hectare and these points involved two soil depths (i.e. 0-20 cm and 20-40 cm) and two locations (i.e. lowland and upland). The Walkley–Black Method was used for SOC analysis while Mann–Kendall Test was employed for climate data analysis. The results exhibit that there have been significant variations in SOC accumulation under the two soil depths and locations. In the lowland areas, SOC was 1.1 and 0.43 MgC ha −1 for the depths 0–20 cm and 20–40, respectively. Besides, in upland areas, SOC was 0.38 and 0.31 MgC ha −1 for the depths 0–20 cm and 20–40, respectively. Most cereal crops require a considerable amount of SOC in the soil that ranges between 0.5 and 2 MgC ha −1 . Additionally, the mean annual rainfall and temperature patterns from 1980 to 2020 declined and intensified at R2 = 0.15 and 0.19, respectively. Therefore, these results inform environmental experts, climate practitioners and other relevant stakeholders to endorse suitable and sustainable environmental management methods in the mountainous areas.
Accumulation of SOC under organic and no-fertilizations, and its influence on crop yields in Tanzania’s semiarid zone
(Informa UK Limited, trading as Taylor & Francis, 2018-04-15) Mkonda, M. Y.; He, X.
Introduction: To estimate differential accumulation of soil organic carbon (SOC) and its ecological significance is very important to smallholder farmers in the Tanzania’s semiarid areas. This study investigated the accumulation of SOC and other important soil nutrients under organic and no-fertilizations, and correlated SOC with crop yields. Using data from long-term experimental study sites of semiarid in Tanzania, we estimated SOC accumulation in different soil treatments and depths where a total of 128 soil samples were collected at the depths of 0–20 cm and 20–40 cm from two villages (sites) with organic fertilization and nofertilization treatments. Sites under organic fertilization were defined as those which have received manure fertilization for more than 5 years on continuum basis. Outcomes: The accumulation of SOC was significantly greater in soils under organic fertilizations (1.15 and 0.80 MgC ha−1 at soil depth and 20–40 cm) and decreased with increasing soil depths. Similarly, TN and P decreased from 0.40 and 2.40 Mg (0–20 cm) to 0.16 and 2.10 Mg (20–40 cm), respectively. Other important soil nutrients such as calcium (Ca2+), potassium (K+), magnesium (Mg2+), and sodium (Na+) had similar pattern. In addition, soil bulk density was less under organic fertilization (1.1 g/cm3) than under no-fertilization (1.2 g/cm3) and it increased with soil depths. Correspondingly, the crop yields were significantly higher (1.6 tn ha−1) under organic fertilizations than (0.6 tn ha−1) under no-fertilizations indicating that crop yields were significantly affected by SOC. Discussion: Organic fertilization i.e., especially cattle manure in the area has considerable fertility potential. To optimize soil fertility potential, we need to consider such kind of fertilization from household to national level. Conclusion: Our results demonstrated that manure application was the best fertilization method for improving soil fertility in most croplands of Tanzania’s semiarid areas, especially in this era of climate change scenarios.
Activity of sterols isolated from the leaves of commiphora swynnertonii (Burtt) against some nosocomial infectious bacteria
(The Journal of Phytopharmacology, 2022-09-04) Credo, David; Mabiki, Faith P.; Machumi, Francis; Chacha, Musa; Cornett, Claus
Commiphora swynnertonii (Burtt) is traditionally used for medicinal purposes both in humans and animals in Tanzania. Previously, its leaves extract has been demonstrated antibacterial activity. However, there is limited information on identification of pure compounds responsible for its observed antibacterial activity. Therefore, this study was conducted to isolate and evaluate antibacterial activity of pure compounds isolated from its leaves extract. Colum chromatographic separation of its dichloromethane leaves extract afforded the isolation of two sterols namely, Cholest-7-en-3β-ol (1) and β-sitosterol (2). Their structures were deduced by using NMR data experimentally obtained and comparison with spectral data available in literatures. The sterols were evaluated for activity against four nosocomial infectious bacteria namely; Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa to determine Minimum Inhibitory Concentrations (MIC) by broth microdilution method. Cholest-7-en-3β-ol (1) demonstrated strong activity against S. aureus (MIC= 0.5 mg/ml) and weak activities (MIC >2mg/ml) against other bacteria. β-sitosterol (2) exhibited weak activities (MIC >2mg/ml) against all tested bacteria. Therefore, presence of antibacterial active compound(s) such as Cholest-7-en-3β-ol (1) among others in the leaves of C. swynnertonii can justify its earlier reported antibacterial activity and further confirms the claimed traditional uses of this plant in the treatment of bacterial infections.
Adaptive cache server selection and resource allocation strategy in mobile edge computing
(International journal of information communication technologies and human development (ijicthd), 2023) Mahenge, Michael Pendo John; Kitindi, Edvin Jonathan
The enormous increase of data traffic generated by mobile devices emanate challenges for both internet service providers (ISP) and content service provider (CSP). The objective of this paper is to propose the cost-efficient design for content delivery that selects the best cache server to store repeatedly accessed contents. The proposed strategy considers both caching and transmission costs. To achieve the equilibrium of transmission cost and caching cost, a weighted cost model based on entropy-weighting- method (EWM) is proposed. Then, an adaptive cache server selection and resource allocation strategy based on deep-reinforcement-learning (DRL) is proposed to place the cache on best edge server closer to end-user. The proposed method reduces the cost of service delivery under the constraints of meeting server storage capacity constraints and deadlines. The simulation experiments show that the proposed strategy can effectively improve the cache-hit rate and reduce the cache-miss rate and content access costs.
Adopting competence-based curriculum to improve quality of secondary education in Tanzania: “is it a dream or reality”?
(2015-11-11) Makunja, G.
This paper assessed the adoption of competence based curriculum (CBC) to improve quality of secondary education in Tanzania whether is a dream or reality. This paper tries to determine teachers’ knowledge in implementing competence based curriculum. The study employed a mixed research approaches which utilised a descriptive survey design. Purposive and simple random sampling procedures were used to select a total of 162 respondents from six public secondary schools in Morogoro Municipality; six heads of secondary schools, six academic teachers, 102 class teachers and 48 secondary students. The questionnaire, interviews and observations were used to collect requisite information. Quantitative data were analysed by using descriptive statistics to determine frequency and percentage whereas qualitative data were subjected to content analysis. The study established that the majority of teachers lacked requisite knowledge for implementing competence based curriculum during the teaching and learning process. On the basis of these findings, the study concluded that, adoption of competence based curriculum to improve quality of secondary education in Tanzania has yet to translate into quality secondary education. Indeed, teachers, who are the major implementers, lacked knowledge and skills for implementing competence based curriculum effectively. The study, therefore, recommended that efforts be made by the government through the Ministry of Education and Vocational Training (MOEVT) to conduct immediate and regular in-service training to teachers to equip them with necessary knowledge and skills for implementing competence based curriculum efficiently and effectively.
Agricultural history nexus food security and policy framework in Tanzania
(2018) Mkonda, M. Y.; He, X.
Background: Understanding the production trend of the major food crops is an important step for any nation that evaluates her agricultural progress. This evaluation should mostly focus on the yields per unit area. So far, it can also earmark the expansion of farms to determine the general yields trend. The main objective of this paper is to assess the production trend of the major food crops and their efficacy to food security in Tanzania. This is particular important because for the past three decades, the country has failed to control food security (especially food availability and accessibility). Results: Here, crop data from 1980 to 2015 were gathered from the Ministry of Agriculture, Livestock and Fishery (MALF), and in the respective regions. In some incidences, the regional data were averaged to elicit their preciseness. To determine the objectivity of this study, agricultural policy, programs, and plans from MALF were reviewed for similar purpose. Mostly, the Mann-Kendal Test and Microsoft Excel were used for data analyses. The results show that the production of the total yields had a positive trend (i.e., growing at R2 = 0.4 and 0.8), while that of the yields (ton/ha) had a negative trend (i.e., declining at R2 = 0.02 and 0.3). It was further realized that the total yields mostly boomed due to farm expansion. Conclusions: Despite the efforts from various agricultural stakeholders, the country has not yet achieved a sustainable crop yield and food security. Explicitly, this situation has been affecting peoples’ livelihoods, and other sectors either directly or indirectly. Therefore, there is a need to improve the production strategies and approaches (i.e., more especially technology and marketing) to limit this problem.
Agricultural sustainability and food security in agroecological zones of Tanzania
(Springer Nature Switzerland AG, 2021) Mkonda, Msafiri Yusuph
Agricultural sustainability is crucial for developing countries, including Tanzania whose economy and food security entirely depend on agriculture. Tanzania has seven agro-ecological zones with different potentials and challenges to attain agricultural sustainability. These agro-ecological zones are coastal, arid, semi-arid, plateau, southern and western highlands, northern highlands, and alluvial. To attain agricultural sustainability and food security in the country, it is essential to explore biophysical, economic and social dimensions. This chapter reviews the climatic situation, agricultural potentials and agronomic practices. Arid and semi-arid zones are more vulnerable to environmental stress, especially climate change, than plateau, alluvial, and northern and southern highlands. Efficient agricultural sustainability has increased peoples’ income and food security in resilient agro-ecological zones by 50%, and by 10% in vulnerable zones. This has eventually improved the livelihoods of the people in resilient agro-ecological zones, and has allowed cultivation of few crop varieties such as sorghum and millet in vulnerable zones. Areas with the best agronomic practices such as animal manure fertilization have increased crop yields from 0.75 to 1.95 tons ha −1 . As a result, this yield increment has improved the livelihoods of about 70% of Tanzanian farmers who entirely depend in agriculture.
Algorithm for the evaluation of Free and Open Source Software when the Evaluator is "Uncertain"
(North American Institute of Science and Information Technology (NAISIT), 2015-09) Sanga, C; Venter, I. M
Free and Open Source Software is freely available on the Internet and making use of it, could benefit many higher learning institutions in developing countries. However, before adoption, it is necessary to evaluate the software to see if it meets the requirements of the institution. The evaluation of software involves considering the quality attributes of the software, which can either be evaluated objectively or subjectively, depending on whether the attributes are measured directly or indirectly. To handle the subjectivity of qualitative evaluation an algorithm with inherent computational intelligence was developed. The algorithm, Fuzzy Analytic Hierarchy Process incorporates a modified version of extent analysis. It can tolerate fuzziness, ambiguity, imprecision, uncertainty and ill-illustrated judgements. In addition to the improved Fuzzy Analytic Hierarchy Process development, the Group Fuzzy Analytic Hierarchy Process was developed. Using a specially derived set of end-user centric metrics, the algorithm provides the means for evaluating software according to quality attributes. Software developers, to predict end-user requirements, and to more accurately measure end-user satisfaction can use these quality attributes. Soft Systems Methodology was the preferred research methodology in this investigation as it is well suited for fuzzy problems. The algorithm was validated by evaluating Moodle, a free and open source e-learning system, adopted by a University in Tanzania. Students and staff from the university were involved in providing the subjective opinions about the software. The data collected from the subjective evaluation was captured and using Soft System Methodology, the data was analysed cyclically, improving the algorithm with each cycle. The advantages of the proposed final algorithm are: it is efficient, simple to use and cost-effective. It guides the end user to form an informed decision based on the evaluation results of software. The evaluation results determine whether the outlook is pessimistic, moderate or optimistic.

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