African Journal of Science, Technology and Social Sciences最新文献

{"title":"Adsorption of Pb(II), Hg(II) and Cu(II) ions on azacrown ether grafted chitosan films","authors":"Julius Toeri, G. Mungai","doi":"10.58506/ajstss.v1i2.7","DOIUrl":"https://doi.org/10.58506/ajstss.v1i2.7","url":null,"abstract":"The adsorption and desorption of Cu(II), Pb(II) and Hg(II) ions from aqueous solutions by porous azacrown ether grafted chitosan films (Ch-DAC) were studied in a batch adsorption system. The porous Ch-DAC films were prepared by hydroamination reaction of azacrown ether activated double bonds with chitosan by changing the proportion of Ch/DAC with 1:0, 1:0.125, 1:0.167, 1:0.25 and 1:0.5 ratios. Characteristics of the films such as pH of aqueous slurry, pH of zero-point charge (pHzpc), surface area and pore volume, energy dispersive X-ray spectroscopy (EDX), Field Emission - Scanning Electron Microscopy (FE-SEM), Fourier transform infrared (FTIR) were investigated. Factors influencing adsorption performance such as pH of the solution, metal ion concentration, adsorbent dosage and the DAC content were studied. Batch studies, investigating film adsorption capacity and adsorption isotherms for Pb(II), Hg(II) and Cu(II) ion adsorption equilibrium correlated well with Langmuir model. The maximum capacity for the adsorption of Pb(II), Hg(II) and Cu(II) ions calculated from the Langmuir isotherm was 256, 200 and 143 mg/g respectively. Compared with the pure non-grafted chitosan films, the azacrown ether films were proved to have better sorption performance for the Pb(II), Hg(II) and Cu(II) ions at pH 5 to 6.","PeriodicalId":440319,"journal":{"name":"African Journal of Science, Technology and Social Sciences","volume":"69 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134116833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of analytic hierarchy process (AHP) to evaluate maintenance practices in TVET institutions in Kenya","authors":"George Njagi Njeru, P. Muchiri","doi":"10.58506/ajstss.v1i2.15","DOIUrl":"https://doi.org/10.58506/ajstss.v1i2.15","url":null,"abstract":"TVET institutions are expected to produce the bulk of Kenya’s middle level manpower equipped with skills to drive the attainment of infrastructural objectives of Kenya Vision 2030. However inadequate training resources brought about by poor management practices continue to impede efforts to equip Kenyan youth with employable technical skills. A programme to re-equip the institutions has been effected but it requires maintenance practices to be aligned with the new acquisitions to ensure they are constantly available for training.  A survey was conducted through a questionnaire to engineering departments to evaluate compliance with maintenance performance indicators (PIs); a 5-point rating scale was used to score responses in the questionnaire that returned a combined Maintenance Management System Effectiveness Index of 0.517. This indicated a need for improvement of maintenance practices. The Analytical Hierarchical Process (AHP) method was applied which identified predictive maintenance policy as the best one to apply","PeriodicalId":440319,"journal":{"name":"African Journal of Science, Technology and Social Sciences","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126734856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A numerical analysis of the performance of linear interpolation schemes coupled with finite volume method in determining velocity distribution for confined convection-diffusion turbulent flow field","authors":"Jane Gatwiri, S. Karanja, D. Theuri","doi":"10.58506/ajstss.v1i2.125","DOIUrl":"https://doi.org/10.58506/ajstss.v1i2.125","url":null,"abstract":"Numerical methods are widely used to obtain solutions of fluid flow problems because they well compliment experimental methods. The numerical results obtained are however never exact due to errors emanating from the scheme used in discretizing the governing equations and the flow domain. For convection-diffusion flow, the magnitudes of these errors vary depending on the scheme used to interpolate the nodal values of the flow quantities to the interfaces. The precision level of an interpolation scheme is determined by its ability to minimize these errors hence generating results that are consistent with experimental results. This paper documents the performance of three linear interpolation schemes; upwind differencing, central differencing scheme and the hybrid scheme in obtaining velocity profiles for a convection-diffusion turbulent flow field. The field variables present in the governing equations are decomposed into a mean and a fluctuating component and averaged so as to reduce the enormous scales inherent in a turbulent flow regime. The closure problem was solved using the   turbulence model. The turbulence equations have been converted into discrete form using the robust finite volume discretization technique. The discretized equations are solved using a segregated pressure-based algorithm. The numerical results were validated using the benchmark results of Ampofo and Karayiannis, (2003). The results revealed that linear interpolation schemes are not appropriate in analyzing velocity distribution for confined convection-diffusion turbulent flows because the results obtained using all the three linear schemes were inconsistent with experimental results.","PeriodicalId":440319,"journal":{"name":"African Journal of Science, Technology and Social Sciences","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124633522","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development and validation of digital medical laboratory educational platform","authors":"Patrick Mutharia Ndiba, C. Gichuki, Amos Chege, Joshua Kibera","doi":"10.58506/ajstss.v1i2.17","DOIUrl":"https://doi.org/10.58506/ajstss.v1i2.17","url":null,"abstract":"With the rise in whole slide scanner technology, large numbers of tissue slides are being scanned and represented and archived digitally. While digital pathology has substantial implications for telepathology, second opinions and education, there are also huge research opportunities with this new type of digital data. Accessibility to large digital repositories of tissue slides is a huge potential educational resource for medical students and pathology residents. In addition to education of medical students and residents, and clinical adoption, digital pathology has been transformative for computational imaging research. Many universities also do not have active pathology laboratories which are necessary in providing a steady flow of real life cases for medical training and research. Therefore, this project aimed at designing and validating a digital medical laboratory educational platform where learners could access the virtual slides from their individual student portals irrespective of where they log in from. With the use of a digital slide scanner, physical slides from the manual laboratory repository were scanned and stored in the cloud in digital format. The two platforms of both institutions were integrated so that the students’ online leaning portal was in sync with the Pathology Network’s digital repository. Once the integration was successful, the students were able to access and interact with the learning materials and virtual slides for Cytology and Cytological Stains which was the scheduled topic for teaching and learning. \u0000  \u0000The study recruited thirty five students from Meru University of Science and Technology pursuing undergraduate studies in Medical Microbiology. Majority of the students (33 out of 35; 94.3%) indicated that digital pathology enhanced their understanding of the topic of study due to availability of virtual slides with ease and at any time of day. All students (35 out of 35; 100%) felt that digital pathology teaching was beneficial to them as Medical Microbiology students and they all expressed their hope in continued learning with digital pathology to supplement face-to-face lectures. This preliminary study proved that the concept of digital pathology education is a viable venture in medical training particularly, in pathology and medical laboratory. There is need for additional work in terms of inclusion of more areas of coverage in the field laboratory medicine and development of virtual learning content, in order to validate the concept and upscale the local digital slide repository to enrich the use of digital pathology in Kenya and the region and also enhance teaching and learning. Digital pathology coupled with virtual microscopy shall progressively improve in the delivery of pathology and laboratory medicine training and education.","PeriodicalId":440319,"journal":{"name":"African Journal of Science, Technology and Social Sciences","volume":"112 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125160608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of varying soil moisture on growth and yield of Chia (Salvia hispanica l.) in Meru county, Kenya.","authors":"Moses Njoka Muriithi, P. Masinde, C. Mwenda","doi":"10.58506/ajstss.v1i2.113","DOIUrl":"https://doi.org/10.58506/ajstss.v1i2.113","url":null,"abstract":"moisture content at different growth stages is unknown. A field experiment was conducted in March-June and June-October 2021 to determine the influence of different soil moisture regimes on the growth and yield of Chia. A randomized complete block design with three replications was used. Chia plants were subjected to four soil moisture regimes; (i)watering to the seedling stage (seedling), (ii) watering to the vegetative stage (vegetative), and (iii) watering to the flowering stage (flowering) (iv) continuous watering (control). High soil moisture of 89-93 %, significantly increased (p≤0.05) the vegetative growth of Chia plants. Plant height, stem diameter and number of leaves increased by 65-180%, 100-109% and 92-565%, respectively. 20-40% reduction in the available soil water to the plant decreased growth of Chia. Low soil moisture of 30-32 % caused plants to produce 172-220% less seed yield than control plants. Seasonal variation was noted, with increased vegetative growth and seed yield reported in the March-June 2021 season compared to the June-October 2021 season. Decreased vegetative growth and yields was a result from inhibition of cell enlargement or cell division under reduced soil moisture. The study recommends watering to the flowering stage as the best practice for water saving and increasing Chia production in Kenya. \u0000 ","PeriodicalId":440319,"journal":{"name":"African Journal of Science, Technology and Social Sciences","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122854085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of digital contact tracing technologies employed during COVID-19 Pandemic","authors":"Fridah Kainyu, M. Mwadulo","doi":"10.58506/ajstss.v1i2.112","DOIUrl":"https://doi.org/10.58506/ajstss.v1i2.112","url":null,"abstract":"Corona virus (COVID-19) is a worldwide pandemic that was first reported in Wuhan, China 2019.The virus claimed lives and negatively changed the mobility patterns of humans. As a measure to control the spread of the virus, Digital Contact Tracing Technologies (DCTTs) were employed to contain the virus. The (DCTTs) are used to track and notify users digitally about their interactions with infected individuals and help strengthen health service systems. The most widely used Digital Contact Tracing Technologies include those that use Global Positioning, Bluetooth, Quick Response (QR) Codes and Wireless Fidelity (Wi-Fi). These technologies depend on monitoring symptoms, mobility of a person, location and proximity of individuals. This paper reviews literature by analyzing the Digital Contact Tracing Technologies (DCTTs) employed for COVID-19 through a desk study. The review highlights the advantages and disadvantages of using these technologies, with an aim of recommending ways in which the technologies can be used to attain maximum benefit. \u0000 ","PeriodicalId":440319,"journal":{"name":"African Journal of Science, Technology and Social Sciences","volume":"31 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116335904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Necessity for up-scaling resource mobilization for implementation of competency-based curriculum at basics education cycle","authors":"I. Njati","doi":"10.58506/ajstss.v1i2.10","DOIUrl":"https://doi.org/10.58506/ajstss.v1i2.10","url":null,"abstract":"School resources comprise necessary materials, both financial and human. A growth towards evidence-based allocation and utilization of school resources is affected by inadequate capacity of the school managers, ministry of education, parents and non-governmental organizations. Inadequate teaching and learning resources limit individual schools' strength to make judicial decisions on equitable trade-offs in education resource demand, supply and consumption. This work sought to identify the locally available resources for utility in competency-based- curriculum implementation, improve the available resources for enhancing teaching and learning, and analyze factors militating against effective mobilization and utilization of resources at the basic education level. Online surveys were used in collecting secondary data. Journals, internet, textbooks and research reports were sampled for data gathering through a stratified sampling technique. The findings showed that the rural-urban migration factors significantly affect trained teachers from arid areas by moving away from their local homes to towns in search of jobs. When learners fail to interact adequately with qualified teachers, the consequences are dire, resulting in learners' poor acquisition of competencies. It was ascertained that more than 70% of the teachers teaching at Kakuma Refugee Camp were not sensitive to learners' plights. This was due to their weak and inadequate education and training background coupled with poor teaching and learning resources. 60% of the tutors at Kakuma Refugee Camp were untrained in pedagogical and andragogical skills necessary for giving instructions in a competency-based curriculum. It was established that the cost of needed materials and training for improving CBC implementation was expensive. Therefore, action research could explore avenues for economies of scale by sharing materials and coordinating purchases between and among neighborhood schools. This is because the critical mass of activities under CBC such as arts, music and sports all create new opportunities for supply chains that present avenues for partnering with organizations that support basic education activities that has remained unexploited. In conclusion, the national and county government's department of pre-primary and basic education level should generate guidance on the use of alternative and low-cost materials for teaching to alleviate the persistent shortages of teaching resources. \u0000  \u0000Key Words: resources, mobilization, utilization; competency-based-curriculum; enhancing                       teaching and learning,","PeriodicalId":440319,"journal":{"name":"African Journal of Science, Technology and Social Sciences","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129058732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"review of techniques for morphological analysis in natural language processing","authors":"Mutwiri George Muthee, Mutua Makau, Omamo Amos","doi":"10.58506/ajstss.v1i2.11","DOIUrl":"https://doi.org/10.58506/ajstss.v1i2.11","url":null,"abstract":"Natural language is a crucial tool to facilitate communication in our day-to-day activities. This can be achieved either in text or speech forms. Natural language processing (NLP) involves making computers understand and process natural language. NLP has enhanced the way humans interact with computers, from having computers use speech to talk to humans as well as having computers translate human speech. Apart from speech, computers also create and understand sentences in natural language in a process called morphological analysis. Morphological analysis is an important part in natural language processing, being applied as a preprocessing step in most NLP tasks. Morphological analysis consists of four subtasks, that is, lemmatization, part-of-speech (POS) tagging, word segmentation and stemming.  In this paper, we explore in detail each of these tasks of morphological analysis. We then evaluate the techniques used in this NLP field. Finally, we give a summary of the results of each of these techniques.","PeriodicalId":440319,"journal":{"name":"African Journal of Science, Technology and Social Sciences","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130630866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A critical review on integration of virtual labs to enhance access to stem education for girls during and post Covid-19","authors":"Amos O. Omamo, S. Wandili, S. Mutua, Hilda Omae, Kenneth Gachoka, Samuel Odoyo, Erick Awuoche","doi":"10.58506/ajstss.v1i2.121","DOIUrl":"https://doi.org/10.58506/ajstss.v1i2.121","url":null,"abstract":"Practical activities are extremely important in teaching sciences as they aid the students in comprehending scientific concepts through participatory learning. However, most Kenyan public schools lack well equipped laboratories. Additionally, the diminishing resources resulting from post-COVID effects offer no beam of hope. Disruption from COVID also poses critical challenges of handling physical devices in times of such pandemics. To address this, the Integration of Virtual Labs to Enhance STEM Education for Girls (IVLESTEG) project was conceptualized to enhance girl’s access to Science, Technology, Engineering and Mathematic (STEM) subjects in Kenyan secondary schools. The aim of this research study was to critically appraise the current technology models in relation  to girls’ access to STEM education with the overall objective of exploring the potential of e-learning in promoting participation of female students in STEM subjects in Kenya.  Upon development and implementation of learning in the V-labs, quasi experiments were conducted to determine the effectiveness of use of V-Labs in enhancing the participation of female students in STEM disciplines in secondary schools. Schools were  randomly chosen and classified as either experimental or control sites. This method allowed  for comparison of performance in STEM subjects of the female learners who were exposed to learning in the V-labs and those not. The findings will contribute to the development  of a framework for  appraising models for ICT use in STEM teaching and learning processes for girls that can inform practice, policy and research.\u0000 ","PeriodicalId":440319,"journal":{"name":"African Journal of Science, Technology and Social Sciences","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134070617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Resource recovery from organic wastes using Black Soldier Fly Larvae","authors":"Rosemary M. Matheka, J. Raude, S. Murunga","doi":"10.58506/ajstss.v1i2.14","DOIUrl":"https://doi.org/10.58506/ajstss.v1i2.14","url":null,"abstract":"Solid waste management is a cross-cutting issue impacting many aspects of the environment, society and economic development. Cities of low- and middle-income countries are currently facing severe challenges in management of the increasing amount of solid waste produced, particularly the organic waste fraction. This review presents information in literature about the utilization of Black soldier fly (BSF) in managing organic waste. It summarizes the approaches in organic waste management, use of BSF in organic waste management, life cycle and growth conditions of BSF and the benefits of utilizing BSF for resource recovery. Organic waste treatment using BSF is an emerging waste management technology with minimal global warming potential. The BSF larvae helps in carbon sequestration and is a protein source which can help alleviate the raising global demand for animal feed. The BSF larval model provides for nutrient recycling, waste reduction and value addition significantly contributing to economic viability, competitiveness and strategic development in environmental management and agriculture.","PeriodicalId":440319,"journal":{"name":"African Journal of Science, Technology and Social Sciences","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125295905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}