Search results for: Johan Labuschagne
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 43

Search results for: Johan Labuschagne

43 Reduced Tillage and Bio-stimulant Application Can Improve Soil Microbial Enzyme Activity in a Dryland Cropping System

Authors: Flackson Tshuma, James Bennett, Pieter Andreas Swanepoel, Johan Labuschagne, Stephan van der Westhuizen, Francis Rayns

Abstract:

Amongst other things, tillage and synthetic agrochemicals can be effective methods of seedbed preparation and pest control. Nonetheless, frequent and intensive tillage and excessive application of synthetic agrochemicals, such as herbicides and insecticides, can reduce soil microbial enzyme activity. A decline in soil microbial enzyme activity can negatively affect nutrient cycling and crop productivity. In this study, the effects of four tillage treatments; continuous mouldboard plough; shallow tine-tillage to a depth of about 75 mm; no-tillage; and tillage rotation (involving shallow tine-tillage once every four years in rotation with three years of no-tillage), and two rates of synthetic agrochemicals (standard: with regular application of synthetic agrochemicals; and reduced: fewer synthetic agrochemicals in combination with bio-chemicals/ or bio-stimulants) on soil microbial enzyme activity were investigated between 2018 and 2020 in a typical Mediterranean climate zone in South Africa. Four different bio-stimulants applied contained: Trichoderma asperellum, fulvic acid, silicic acid, and Nereocystis luetkeana extracts, respectively. The study was laid out as a complete randomised block design with four replicated blocks. Each block had 14 plots, and each plot measured 50 m x 6 m. The study aimed to assess the combined impact of tillage practices and reduced rates of synthetic agrochemical application on soil microbial enzyme activity in a dryland cropping system. It was hypothesised that the application of bio-stimulants in combination with minimum soil disturbance will lead to a greater increase in microbial enzyme activity than the effect of applying either in isolation. Six soil cores were randomly and aseptically collected from each plot for microbial enzyme activity analysis from the 0-150 mm layer of a field trial under a dryland crop rotation system in the Swartland region. The activities of four microbial enzymes, β-glucosidase, acid phosphatase, alkaline phosphatase and urease, were assessed. The enzymes are essential for the cycling of glucose, phosphorus, and nitrogen, respectively. Microbial enzyme activity generally increased with a reduction of both tillage intensity and synthetic agrochemical application. The use of the mouldboard plough led to the least (P<0.05) microbial enzyme activity relative to the reduced tillage treatments, whereas the system with bio-stimulants (reduced synthetic agrochemicals) led to the highest (P<0.05) microbial enzyme activity relative to the standard systems. The application of bio-stimulants in combination with reduced tillage, particularly no-tillage, could be beneficial for enzyme activity in a dryland farming system.

Keywords: bio-stimulants, soil microbial enzymes, synthetic agrochemicals, tillage

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42 Enhanced Ripening Behaviour of Manganese Doped Cadmium Selenide Quantum Dots (Mn-doped CdSe QDs)

Authors: N. A. Hamizi, M. R. Johan, Y. H. Hor, A. N. Sabri, Y. Y. A. Yong

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In this research, Mn-doped CdSe QDs is synthesized by using paraffin liquid as the reacting solvent and oleic acid as the ligands for Cd in order to produce Mn-doped CdSe QDs in zinc-blende crystal structure. Characterization studies for synthesized Mn-doped CdSe QDs are carried out using UV-visible and photoluminescence spectroscopy. The absorption wavelengths in UV-vis test and emission wavelengths in PL test were increase with the increases in the ripening temperature and time respectively.

Keywords: semiconductor, chemical synthesis, optical properties, ripening

Procedia PDF Downloads 365
41 Online Formative Assessment Challenges Experienced by Grade 10 Physical Sciences Teachers during Remote Teaching and Learning

Authors: Celeste Labuschagne, Sam Ramaila, Thasmai Dhurumraj

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Although formative assessment is acknowledged as crucial for teachers to gauge students’ understanding of subject content, applying formative assessment in an online context is more challenging than in a traditional Physical Sciences classroom. This study examines challenges experienced by Grade 10 Physical Sciences teachers when enacting online formative assessment. The empirical investigation adopted a generic qualitative design and involved three purposively selected Grade 10 Physical Sciences teachers from three different schools and quintiles within the Tshwane North District in South Africa. Data were collected through individual and focus group interviews. Technological, pedagogical, and content knowledge (TPACK) was utilised as a theoretical framework underpinning the study. The study identified a myriad of challenges experienced by Grade 10 Physical Sciences teachers when enacting online formative assessment. These challenges include the utilisation of Annual Teaching Plans, lack of technological knowledge, and internet connectivity. The Department of Basic Education faces the key imperative to provide continuous teacher professional development and concomitant online learning materials that can facilitate meaningful enactment of online formative assessment in various educational settings.

Keywords: COVID-19, challenges, online formative assessment, physical sciences, TPACK

Procedia PDF Downloads 65
40 Forward Conditional Restricted Boltzmann Machines for the Generation of Music

Authors: Johan Loeckx, Joeri Bultheel

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Recently, the application of deep learning to music has gained popularity. Its true potential, however, has been largely unexplored. In this paper, a new idea for representing the dynamic behavior of music is proposed. A ”forward” conditional RBM takes into account not only preceding but also future samples during training. Though this may sound controversial at first sight, it will be shown that it makes sense from a musical and neuro-cognitive perspective. The model is applied to reconstruct music based upon the first notes and to improvise in the musical style of a composer. Different to expectations, reconstruction accuracy with respect to a regular CRBM with the same order, was not significantly improved. More research is needed to test the performance on unseen data.

Keywords: deep learning, restricted boltzmann machine, music generation, conditional restricted boltzmann machine (CRBM)

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39 Experiential Learning: Roles and Attributes of an Optometry Educator Recommended by a Millennial Generation

Authors: E. Kempen, M. J. Labuschagne, M. P. Jama

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There is evidence that experiential learning is truly influential and favored by the millennial generation. However, little is known about the role and attributes an educator has to adopt during the experiential learning cycle, especially when applied in optometry education. This study aimed to identify the roles and attributes of an optometry educator during the different modes of the experiential learning cycle. Methods: A qualitative case study design was used. Data was collected using an open-ended questionnaire survey, following the application of nine different teaching-learning methods based on the experimental learning cycle. The total sample population of 68 undergraduate students from the Department of Optometry at the University of the Free State, South Africa were invited to participate. Focus group interviews (n=15) added additional data that contributed to the interpretation and confirmation of the data obtained from the questionnaire surveys. Results: The perceptions and experiences of the students identified a variety of roles and attributes as well as recommendations on the effective adoption of these roles and attributes. These roles and attributes included being knowledgeable, creating an interest, providing guidance, being approachable, building confidence, implementing ground rules, leading by example, and acting as a mediator. Conclusion: The findings suggest that the actions of an educator have the most substantial impact on students’ perception of a learning experience. Not only are the recommendations based on the views of a millennial generation, but the implementation of the personalized recommendations may also transform a learning environment. This may lead an optometry student to a deeper understanding of knowledge.

Keywords: experiences and perceptions, experiential learning, millennial generation, recommendation for optometry education

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38 A Conceptual Framework of Digital Twin for Homecare

Authors: Raja Omman Zafar, Yves Rybarczyk, Johan Borg

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This article proposes a conceptual framework for the application of digital twin technology in home care. The main goal is to bridge the gap between advanced digital twin concepts and their practical implementation in home care. This study uses a literature review and thematic analysis approach to synthesize existing knowledge and proposes a structured framework suitable for homecare applications. The proposed framework integrates key components such as IoT sensors, data-driven models, cloud computing, and user interface design, highlighting the importance of personalized and predictive homecare solutions. This framework can significantly improve the efficiency, accuracy, and reliability of homecare services. It paves the way for the implementation of digital twins in home care, promoting real-time monitoring, early intervention, and better outcomes.

Keywords: digital twin, homecare, older adults, healthcare, IoT, artificial intelligence

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37 Identification of Superior Cowpea Mutant Genotypes, Their Adaptability, and Stability Under South African Conditions

Authors: M. Ntswane, N. Mbuma, M. Labuschagne, A. Mofokeng, M. Rantso

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Cowpea is an essential legume for the nutrition and health of millions of people in different regions. The production and productivity of the crop are very limited in South Africa due to a lack of adapted and stable genotypes. The improvement of nutritional quality is made possible by manipulating the genes of diverse cowpea genotypes available around the world. Assessing the adaptability and stability of the cowpea mutant genotypes for yield and nutritional quality requires examining them in different environments. The objective of the study was to determine the adaptability and stability of cowpea mutant genotypes under South African conditions and to identify the superior genotypes that combine grain yield components, antioxidants, and nutritional quality. Thirty-one cowpea genotypes were obtained from the Agricultural Research Council grain crops (ARC-GC) and were planted in Glen, Mafikeng, Polokwane, Potchefstroom, Taung, and Vaalharts during the 2021/22 summer cropping season. Significant genotype by location interactions indicated the possibility of genetic improvement of these traits. The genotype plus genotype by environment indicated broad adaptability and stability of mutant genotypes. The principal component analysis identified the association of the genotypes with the traits. Phenotypic correlation analysis showed that Zn and protein content were significant and positively correlated and suggested the possibility of indirect selection of these traits. Results from this study could be used to help plant breeders in making informed decisions and developing nutritionally improved cowpea genotypes with the aim of addressing the challenges of poor nutritional quality.

Keywords: cowpea seeds, adaptability, stability, mineral elements, protein content

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36 Creating a Safe Learning Environment Based on the Experiences and Perceptions of a Millennial Generation

Authors: E. Kempen, M. J. Labuschagne, M. P. Jama

Abstract:

There is evidence that any learning experience should happen in a safe learning environment as students then will interact, experiment, and construct new knowledge. However, little is known about the specific elements required to create a safe learning environment for the millennial generation, especially in optometry education. This study aimed to identify the specific elements that will contribute to a safe learning environment for the millennial generation of optometry students. Methods: An intrinsic qualitative case study was undertaken with undergraduate students from the Department of Optometry at the University of the Free State, South Africa. An open-ended questionnaire survey was completed after the application of nine different teaching-learning methods based on the experiential learning cycle. A total number of 307 questionnaires were analyzed. Two focus group interviews were also conducted to provide additional data to supplement the data and ensure the triangulation of data. Results: Important elements based on the opinions, feelings, and perceptions of student respondents were analyzed. Students feel safe in an environment with which they are familiar, and when they are familiar with each other, the educators, and the surroundings. Small-group learning also creates a safe and familiar environment. Both these elements create an environment where they feel safe to ask questions. Students value an environment where they are able to learn without influencing their marks or disadvantaging the patients. They enjoy learning from their peers, but also need personal contact with educators. Elements such as consistency and an achievable objective also were also analyzed. Conclusion: The findings suggest that to respond to the real need of this generation of students, insight must be gained in students’ perceptions to identify their needs and the learning environment to optimize learning pedagogies. With the implementation of these personalized elements, optometry students will be able to take responsibility and accountability for their learning.

Keywords: experiences and perceptions, safe learning environment, millennial generation, recommendation for optometry education

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35 A Syntactic Errors Analysis in the Malaysian ESL Learners' Written Composition

Authors: Annie Gedion, Johan Severinus Tati, Jacinta Caroline Peter

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Syntax error analysis studies have a significant role in English language teaching especially in the second language. This study investigates the syntax errors in written composition by 50 multilingual ESL learners in Politeknik Kota Kinabalu Sabah, Malaysia. The subjects speak their own dialect, Malay as their second language and English as their third or foreign language. Data were collected from the written discourse in the form of descriptive essays. The subjects were asked to write in the classroom within 45 minutes. 15 categories of errors were classified into a set of syntactic categories and were analysed based on the five steps of the syntactic analysis procedure. The findings of the study showed that the mother tongue interference, as well as lack of vocabulary and grammar knowledge, were the major sources of syntax errors in the learners’ written composition. Learners should be exposed to the differentiation of Malay and English grammar to avoid interference and effective learning of second language writing.

Keywords: errors analysis, syntactic analysis, English as a second language, ESL writing

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34 Treatment and Reuse of Nonmetallic PCBs Waste

Authors: Johan Sohaili, Siti Suhaila Mohamad, Shantha Kumari Muniyandi

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The strength development, durability and leachability aspects of mortar added with nonmetallic printed circuit board (NMPCBs) were investigated. This study aims to propose methods for treatment and reuse of NMPCBs waste. The leachability of raw NMPCBs was tested for toxicity by performing the Crushed Block Leachability (CBL) test. The effectiveness of the treatment was evaluated by performing compressive, flexural strength, durability and whole block leachability (WBL) tests on the mortar. The results indicated that the concentration of metals leach from the raw NMPCBs are within the standard limits and higher than the concentration of metals from WBL test. The compressive and flexural strength of the NMPCBs mortar was generally lower than the standard mortar. From durability tests, weight and compressive strength both of mortars was decrease after soaking in acid solution. As a conclusion, the treated NMPCBs can be reused in profitable and environmentally friendly ways and has broad application prospects.

Keywords: nonmetallic, printed circuit board, treatment, reuse

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33 An Ultrasonic Signal Processing System for Tomographic Imaging of Reinforced Concrete Structures

Authors: Edwin Forero-Garcia, Jaime Vitola, Brayan Cardenas, Johan Casagua

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This research article presents the integration of electronic and computer systems, which developed an ultrasonic signal processing system that performs the capture, adaptation, and analog-digital conversion to later carry out its processing and visualization. The capture and adaptation of the signal were carried out from the design and implementation of an analog electronic system distributed in stages: 1. Coupling of impedances; 2. Analog filter; 3. Signal amplifier. After the signal conditioning was carried out, the ultrasonic information was digitized using a digital microcontroller to carry out its respective processing. The digital processing of the signals was carried out in MATLAB software for the elaboration of A-Scan, B and D-Scan types of ultrasonic images. Then, advanced processing was performed using the SAFT technique to improve the resolution of the Scan-B-type images. Thus, the information from the ultrasonic images was displayed in a user interface developed in .Net with Visual Studio. For the validation of the system, ultrasonic signals were acquired, and in this way, the non-invasive inspection of the structures was carried out and thus able to identify the existing pathologies in them.

Keywords: acquisition, signal processing, ultrasound, SAFT, HMI

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32 An Impairment of Spatiotemporal Gait Adaptation in Huntington's Disease when Navigating around Obstacles

Authors: Naznine Anwar, Kim Cornish, Izelle Labuschagne, Nellie Georgiou-Karistianis

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Falls and subsequent injuries are common features in symptomatic Huntington’s disease (symp-HD) individuals. As part of daily walking, navigating around obstacles may incur a greater risk of falls in symp-HD. We designed obstacle-crossing experiment to examine adaptive gait dynamics and to identify underlying spatiotemporal gait characteristics that could increase the risk of falling in symp-HD. This experiment involved navigating around one or two ground-based obstacles under two conditions (walking while navigating around one obstacle, and walking while navigating around two obstacles). A total of 32 participants were included, 16 symp-HD and 16 healthy controls with age and sex matched. We used a GAITRite electronic walkway to examine the spatiotemporal gait characteristics and inter-trail gait variability when participants walked at their preferable speed. A minimum of six trials were completed which were performed for baseline free walk and also for each and every condition during navigating around the obstacles. For analysis, we separated all walking steps into three phases as approach steps, navigating steps and recovery steps. The mean and inter-trail variability (within participant standard deviation) for each step gait variable was calculated across the six trails. We found symp-HD individuals significantly decreased their gait velocity and step length and increased step duration variability during the navigating steps and recovery steps compared with approach steps. In contrast, HC individuals showed less difference in gait velocity, step time and step length variability from baseline in both respective conditions as well as all three approaches. These findings indicate that increasing spatiotemporal gait variability may be a possible compensatory strategy that is adopted by symp-HD individuals to effectively navigate obstacles during walking. Such findings may offer benefit to clinicians in the development of strategies for HD individuals to improve functional outcomes in the home and hospital based rehabilitation program.

Keywords: Huntington’s disease, gait variables, navigating around obstacle, basal ganglia dysfunction

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31 Macroinvertebrate Variation of Endorheic Depression Wetlands within North West and Mpumalanga Provinces, South Africa

Authors: Lee-Ann Foster, Wynand Malherbe, Martin Ferriera, Johan Van Vuren

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Aquatic macroinvertebrates are rarely used in wetland assessments due to their variability. However, in terms of biodiversity, these invertebrates form an important component of wetlands. The objective of this study was to compare the spatial and temporal variation of macroinvertebrate assemblages within endorheic depressions in Mpumalanga and North West Provinces of South Africa. Sampling was conducted over a period of two seasons during 2012 and 2013 at all sampling points to account for a wet and dry season. The identification of macroinvertebrate community samples resulted in 24 taxa for both provinces. Results showed similarities in the structure of communities in perennial endorheic depressions in both provinces with the exception of one or two species. Macroinvertebrates sampled in Mpumalanga depressions (locally called pans) were similar to those reported in previous studies completed in the area and most of the macroinvertebrates sampled in Mpumalanga and the North West are known to be commonly found in temporary habitats. The knowledge acquired can now be utilised to enhance the available literature on these systems. Long-term studies have to be implemented to better understand the ecological functioning of the pans in the North West Province.

Keywords: aquatic, macroinvertebrate assemblages, pans, spatial variation

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30 Parameters Adjustment of the Modified UBCSand Constitutive Model for the Potentially Liquefiable Sands of Santiago de Cali-Colombia

Authors: Daniel Rosero, Johan S. Arana, Sebastian Arango, Alejandro Cruz, Isabel Gomez-Gutierrez, Peter Thomson

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Santiago de Cali is located in the southwestern Colombia in a high seismic hazard zone. About 50% of the city is on the banks of the Cauca River, which is the second most important hydric affluent in the country and whose alluvial deposits contain potentially liquefiable sands. Among the methods used to study a site's liquefaction potential is the finite elements method which use constitutive models to simulate the soil response for different load types. Among the different constitutive models, the Modified UBCSand stands out to study the seismic behavior of sands, and especially the liquefaction phenomenon. In this paper, the dynamic behavior of a potentially liquefiable sand of Santiago de Cali is studied by cyclic triaxial and CPTu tests. Subsequently, the behavior of the sand is simulated using the Modified UBCSand constitutive model, whose parameters are calibrated using the results of cyclic triaxial and CPTu tests. The above with the aim of analyze the constitutive model applicability for studying the geotechnical problems associated to liquefaction in the city.

Keywords: constitutive model, cyclic triaxial test, dynamic behavior, liquefiable sand, modified ubcsand

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29 Hohmann Transfer and Bi-Elliptic Hohmann Transfer in TRAPPIST-1 System

Authors: Jorge L. Nisperuza, Wilson Sandoval, Edward. A. Gil, Johan A. Jimenez

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In orbital mechanics, an active research topic is the calculation of interplanetary trajectories efficient in terms of energy and time. In this sense, this work concerns the calculation of the orbital elements for sending interplanetary probes in the extrasolar system TRAPPIST-1. Specifically, using the mathematical expressions of the circular and elliptical trajectory parameters, expressions for the flight time and the orbital transfer rate increase between orbits, the orbital parameters and the graphs of the trajectories of Hohmann and Hohmann bi-elliptic for sending a probe from the innermost planet to all the other planets of the studied system, are obtained. The relationship between the orbital transfer rate increments and the relationship between the flight times for the two transfer types is found. The results show that, for all cases under consideration, the Hohmann transfer results to be the least energy and temporary cost, a result according to the theory associated with Hohmann and Hohmann bi-elliptic transfers. Saving in the increase of the speed reaches up to 87% was found, and it happens for the transference between the two innermost planets, whereas the time of flight increases by a factor of up to 6.6 if one makes use of the bi-elliptic transfer, this for the case of sending a probe from the innermost planet to the outermost.

Keywords: bi-elliptic Hohmann transfer, exoplanet, extrasolar system, Hohmann transfer, TRAPPIST-1

Procedia PDF Downloads 192
28 Onco@Home: Comparing the Costs, Revenues, and Patient Experience of Cancer Treatment at Home with the Standard of Care

Authors: Sarah Misplon, Wim Marneffe, Johan Helling, Jana Missiaen, Inge Decock, Dries Myny, Steve Lervant, Koen Vaneygen

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The aim of this study was twofold. First, we investigated whether the current funding from the national health insurance (NHI) of home hospitalization (HH) for oncological patients is sufficient in Belgium. Second, we compared patient’s experiences and preferences of HH to the standard of care (SOC). Two HH models were examined in three Belgian hospitals and three home nursing organizations. In a first HH model, the blood draw and monitoring prior to intravenous therapy were performed by a trained home nurse at the patient’s home the day before the visit to the day hospital. In a second HH model, the administration of two subcutaneous treatments was partly provided at home instead of in the hospital. Therefore, we conducted (1) a bottom-up micro-costing study to compare the costs and revenues for the providers (hospitals and home care organizations), and (2) a cross-sectional survey to compare patient’s experiences and preferences of the SOC group and the HH group. Our results show that HH patients prefer HH and none of them wanted to return to SOC, although the satisfaction of patients was not significantly different between the two categories. At the same time, we find that costs associated to HH are higher overall. Comparing revenues with costs, we conclude that the current funding from NHI of HH for oncological patients is insufficient.

Keywords: cost analysis, health insurance, preference, home hospitalization

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27 Prevalence and Characteristics of Consumption of Nutraceuticals: The Case Study of Undergraduate Students of Medellin- Colombia, 2013

Authors: Gloria Inés Martínez Domínguez, Lina María Martínez Sánchez, María de los Ángeles Rodríguez Gázquez, Juan Guillermo Jiménez Jiménez, Johan Sebastián Lopera Valle, Natalia Vargas Grisales, Sara Rojas Jiménez, Alejandra Uribe Ocampo, Sara Correa Pérez, Natalia Perilla Hernández, Juan Sebastián Marín Cárdenas

Abstract:

The relationship between diet and chronic or degenerative diseases has led to the development of functional foods such as nutraceuticals. Objective: To determine the prevalence and characteristics of consumption of nutraceuticals in undergraduate students. Methodology: Cross-sectional study. It was a simple random sampling with the Statcalc EpiInfo software vr 6.04. It was designed an instrument for collection of demographic data and consumption of nutraceuticals. Statistical analysis used the SPSS program. Results: 427 students, average age 20.8 years (SD 3.1), 56.1% were women. The life prevalence of nutraceuticals consumption was 66.3% and the annual 51.8%. The main reasons for consumption were as food complement 32.8% and prevent diseases 20.1%. Conclusion: The high prevalence of nutraceuticals observed is comparable to that reported in the literature, which suggests an increasing trend in the habit of consumption of dietary supplement which have a preventive or protective effect on health.

Keywords: dietary supplements, food, health, functional food, Colombia

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26 Automatic Identification and Monitoring of Wildlife via Computer Vision and IoT

Authors: Bilal Arshad, Johan Barthelemy, Elliott Pilton, Pascal Perez

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Getting reliable, informative, and up-to-date information about the location, mobility, and behavioural patterns of animals will enhance our ability to research and preserve biodiversity. The fusion of infra-red sensors and camera traps offers an inexpensive way to collect wildlife data in the form of images. However, extracting useful data from these images, such as the identification and counting of animals remains a manual, time-consuming, and costly process. In this paper, we demonstrate that such information can be automatically retrieved by using state-of-the-art deep learning methods. Another major challenge that ecologists are facing is the recounting of one single animal multiple times due to that animal reappearing in other images taken by the same or other camera traps. Nonetheless, such information can be extremely useful for tracking wildlife and understanding its behaviour. To tackle the multiple count problem, we have designed a meshed network of camera traps, so they can share the captured images along with timestamps, cumulative counts, and dimensions of the animal. The proposed method takes leverage of edge computing to support real-time tracking and monitoring of wildlife. This method has been validated in the field and can be easily extended to other applications focusing on wildlife monitoring and management, where the traditional way of monitoring is expensive and time-consuming.

Keywords: computer vision, ecology, internet of things, invasive species management, wildlife management

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25 Studies on Toxicity and Mechanical Properties of Nonmetallic Printed Circuit Boards Waste in Recycled HDPE Composites

Authors: Shantha Kumari Muniyandi, Johan Sohaili, Siti Suhaila Mohamad

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The aim of this study was to investigate the suitability of reusing nonmetallic printed circuit boards (PCBs) waste in recycled HDPE (rHDPE) in terms of toxicity and mechanical properties. A series of X-ray Fluorescence Spectrometry (XRF) analysis tests have been conducted on raw nonmetallic PCBs waste to determine the chemical compositions. It can be seen that the nonmetallic PCBs approximately 72% of glass fiber reinforced epoxy resin materials such as SiO2, Al2O3, CaO, MgO, BaO, Na2O, and SrO, 9.4% of metallic materials such as CuO, SnO2, and Fe2O3, and 6.53% of Br. Total Threshold Limit Concentration (TTLC) and Toxicity Characteristic Leaching Procedure (TCLP) tests also have been done to study the toxicity characteristics of raw nonmetallic PCB powders, rHDPE/PCB and virgin HDPE for comparison purposes. For both of the testing, Cu was identified as the highest metal element contained in raw PCBs with the concentration of 905 mg/kg and 59.09 mg/L for TTLC and TCLP, respectively. However, once the nonmetallic PCB was filled in rHDPE composites, the concentrations of Cu were reduced to 134 mg/kg for TTLC and to 3 mg/L for TCLP testing. For mechanical properties testing, incorporation of 40 wt% nonmetallic PCB into rHDPE has increased the flexural modulus and flexural strength by 140% and 36%, respectively. While, Izod Impact strength decreased steadily with incorporation of 10 – 40 wt% nonmetallic PCBs.

Keywords: nonmetallic printed circuit board, recycled HDPE, composites, mechanical properties, total threshold limit concentration, toxicity characteristic leaching procedure

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24 Galtung’s Violence Triangle: We Need to Be Thinking Upside Down

Authors: Michael Fusi Ligaliga

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Peace and Conflict Studies (PACS), despite being a new pedagogical discipline, is a growing interdisciplinary academic field that has expanded its presence from the traditional lens of war, conflict, and violence to addressing various social issues impacting society. Family and domestic violence (FDV) has seldom been explored through the PACS lens despite some studies showing that “on average, nearly 20 people per minute are physically abused by an intimate partner in the United States. Over one year, this equates to more than 10 million women and men.” In the Pacific, FDV rates are some of the highest in the world. The friction caused by cultural practices reinforcing patriarchy and male impunity, compounded by historical colonial experiences, as well as the impact of Christianity on the Pacific region, creates a complex social landscape when thinking about and addressing FDV in the Pacific. This paper seeks to re-examine Johan Galtung’s violence triangle (GVT) theory and its application to understanding FDV in the Pacific. Galtung argues that there are three forms of violence – direct, structural, and cultural. Direct violence (DV) is behaviors that threaten life itself or diminishes the ability of a person to meet his or her basic needs. This form of violence is visible because it is manifested in behaviors such as killing, maiming, sexual assault, etc. Structural violence (SV) exists when people do not get equal access to goods and services (health, education, justice) that enable them to reach their full potential. When ideologies embedded in cultural norms and practices are used to justify and advocate acts of violence by shifting the moral parameters from being wrong to right or acceptable, this, according to Galtung, is referred to as Cultural violence (CV).

Keywords: direct violence, cultural violence, structural violence, indigenous peacebuilding, samoa

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23 Immune Complex Components Act as Agents in Relapsing Fever Borrelia Mediated Rosette Formation

Authors: Mukunda Upreti, Jill Storry, Rafael Björk, Emilie Louvet, Johan Normark, Sven Bergström

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Borrelia duttonii and most other relapsing fever species are Gram-negative bacteria which cause a blood borne infection characterized by the binding of bacterium to erythrocytes. The bacteria associate with two or more erythrocytes to form clusters of cells into rosettes. Rosetting is a major virulence factor and the mechanism is believed to facilitate persistence of bacteria in the circulatory system and the avoidance of host immune cells through masking or steric hindrance effects. However, the molecular mechanisms of rosette formation are still poorly understood. This study aims at determining the molecules involved in the rosette formation phenomenon. Fractionated serum, using different affinity purification methods, was investigated as a rosetting agent and IgG and at least one other serum components were needed for rosettes to form. An IgG titration curve demonstrated that IgG alone is not enough to restore rosette formation level to the level whole serum gives. IgG hydrolysis by IdeS ( Immunoglobulin G-degrading enzyme of Streptococcus pyogenes) and deglycosylation using N-Glycanase proved that the whole IgG molecule regardless of saccharide moieties is critical for Borrelia induced rosetting. Complement components C3 and C4 were also important serum molecules necessary to maintain optimum rosetting rates. The deactivation of complement network and serum depletion with C3 and C4 significantly reduced the rosette formation rate. The dependency of IgG and complement components also implied involvement of the complement receptor (CR1). Rosette formation test with Knops null RBC and sCR1 confirmed that CR1 is also part of Borrelia induced rosette formation.

Keywords: complement components C3 and C4, complement receptor 1, Immunoglobulin G, Knops null, Rosetting

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22 The Impact of Financial Literacy, Perception of Debt, and Perception of Risk Toward Student Willingness to Use Online Student Loan

Authors: Irni Rahmayani Johan, Ira Kamelia

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One of the impacts of the rapid advancement of technology is the rise of digital finance, including peer-to-peer lending (P2P). P2P lending has been widely marketed, including an online student loan that used the P2P platform. This study aims to analyze the effect of financial literacy, perception of debt, and perception of risk toward student willingness to use the online student loan (P2P lending). Using a cross-sectional study design, in collecting the data this study employed an online survey method, with a total sample of 280 undergraduate students of IPB university, Indonesia. This study found that financial literacy, perception of debt, perception of risk, and interest in using online student loans are categorized as low level. While the level of knowledge is found to be the lowest, the first-year students showed a higher level in terms of willingness to use the online student loan. In addition, the second year students recorded a positive perception toward debt. This study showed that level of study, attendance in personal finance course, and student’ GPA is positively related to financial knowledge. While debt perception is negatively related to financial attitudes. Similarly, the negative relationship is found between risk perception and the willingness to use the online student loan. The determinant factor of the willingness to use online student loans is the level of study, debt perception, financial risk perception, and time risk perception. Students with a higher level of study are more likely to have a lower interest in using online student loans. Moreover, students who perceived debt as a financial stimulator, as well as those with higher level of financial risk perceptions and time risk perceptions, tend to show more interest to use the loan.

Keywords: financial literacy, willingness to use, online student loan, perception of risk, perception of debt

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21 Physical Function and Physical Activity Preferences of Elderly Individuals Admitted for Elective Abdominal Surgery: A Pilot Study.

Authors: Rozelle Labuschagne, Ronel Roos

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Individuals often experience a reduction in physical function, quality of life and basic activities of daily living after surgery. This is exponentially true for high-risk patients, especially the elderly and frail individuals. Not much is known about the physical function, physical activity preferences and factors associated with the six-minute walk test of elderly individuals who would undergo elective abdominal surgery in South Africa. Such information is important to design effective prehabilitation physiotherapy programs prior to elective surgery. The purpose of the study was to describe the demographic profile and physical function of elderly patients who would undergo elective surgery and to determine factors associated with their six-minute walk test distance findings. A cross-sectional descriptive study in elderly patients older than 60 years of age who would undergo elective abdominal surgery were consecutively sampled at a private hospital in Pretoria, South Africa. Participants’ demographics were collected and physical function assessed with the Functional Comorbidity Index (FCI), DeMorton Mobility Index (DEMMI), Lawton-Brody Instrumental Activities of Daily Living Scale (IADL) and six-minute walk test (6MWT). Descriptive and inferential statistics were used for data analysis with IBM SPSS 25. A p-value ≤ 0.05 were deemed statistically significant. The pilot study consisted of 12 participants (female (n=11, 91.7%), male (n=1, 8.3%) with a mean age of 65.8 (±4.5) years, body mass index of 28 (±4.2) kg.m2 with one (8.3%) participant being a current smoker and four (33.3%) participants having a smoking history. Nine (75%) participants lived independently at home and three (25%) had caregivers. Participants reported walking (n=6, 50%), stretching exercises (n=1, 8.3%), household chores & gardening (n=2, 16.7%), biking/swimming/running (n=1, 8.3%) as physical activity preferences. Physical function findings of the sample were: mean FCI score 3 (±1.1), DEMMI score 81.1 (±14.9), IADL 95 (±17.3), 6MWT 435.50 (IQR 364.75-458.50) with percentage 6MWT distance achieved 81.8% (IQR 64.4%-87.5%). A strong negative correlation was observed between 6MWT distance walked and FCI (r = -0.729, p=0.007). The majority of study participants reported incorporating some form of physical activity into their daily life as form of exercise. Most participants did not achieve their predicted 6MWT distance indicating less than optimal levels of physical function capacity. The number of comorbidities as determined by the FCI was associated with the distance that participants could walk with the 6MWT. The results of this pilot study could be used to indicate which elderly individuals would benefit most from a pre-surgical rehabilitation program. The main goal of such a program would be to improve physical function capacity as measured by the 6MWT. Surgeons could refer patients based on age and number of comorbidities, as determined by the FCI, to potentially improve surgical outcomes.

Keywords: abdominal surgery, elderly, physical function, six-minute walk test

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20 The Promotion of a Risk Culture: a Descriptive Study of Ghanaian Banks

Authors: Gerhard Grebe, Johan Marx

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The aim of the study is to assess the state of operational risk management and the adoption of an appropriate risk culture in Ghanaian banks. The Bank of Ghana (BoG) joined the Basel Consultative Group (BCG) of the Basel Committee on Bank Supervision (BCBS) in 2021 and is proceeding with the implementation of the Basel III international regulatory framework for banks. The BoG’s Directive about risk management encourages, inter alia, the creation of an appropriate risk culture by Ghanaian banks. However, it is not evident how the risk management staff of Ghanaian banks experience the risk culture and the implementation of operational risk management in the banks where they are employed. Ghana is a developing economy, and it is addressing challenges with its organisational culture. According to Transparency International, successive Ghanaian governments claim to be fighting corruption, but little success has been achieved so far. This points to a possible lack of accountability, transparency, and integrity in the environment in which Ghanaian banks operate and which could influence their risk culture negatively. Purposive sampling was used for the survey, and the questionnaire was completed byGhanaian bank personnel who specializesin operational risk management, risk governance, and compliance, bank supervision, risk analyses, as well as the implementation of the operational risk management requirements of the Basel regulatory frameworks. The respondents indicated that they are fostering a risk culture and implementing monitoring and reporting procedures; the three lines of defence (3LOD); compliance; internal auditing; disclosure of operational risk information; and receiving guidance from the bank supervisor in an attempt to improve their operational risk management practices. However, the respondents reported the following challenges with staff members who are not inside the risk management departments(in order of priority), namelydemonstrating a risk culture, training and development; communication; reporting and disclosure; roles and responsibilities; performance appraisal; and technological and environmental barriers. Recommendations to address these challenges are provided

Keywords: ghana, operational risk, risk culture, risk management

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19 Quantification of Factors Contributing to Wave-In-Deck on Fixed Jacket Platforms

Authors: C. Y. Ng, A. M. Johan, A. E. Kajuputra

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Wave-in-deck phenomenon for fixed jacket platforms at shallow water condition has been reported as a notable risk to the workability and reliability of the platform. Reduction in reservoir pressure, due to the extraction of hydrocarbon for an extended period of time, has caused the occurrence of seabed subsidence. Platform experiencing subsidence promotes reduction of air gaps, which eventually allows the waves to attack the bottom decks. The impact of the wave-in-deck generates additional loads to the structure and therefore increases the values of the moment arms. Higher moment arms trigger instability in terms of overturning, eventually decreases the reserve strength ratio (RSR) values of the structure. The mechanics of wave-in-decks, however, is still not well understood and have not been fully incorporated into the design codes and standards. Hence, it is necessary to revisit the current design codes and standards for platform design optimization. The aim of this study is to evaluate the effects of RSR due to wave-in-deck on four-legged jacket platforms in Malaysia. Base shear values with regards to calibration and modifications of wave characteristics were obtained using SESAM GeniE. Correspondingly, pushover analysis is conducted using USFOS to retrieve the RSR. The effects of the contributing factors i.e. the wave height, wave period and water depth with regards to the RSR and base shear values were analyzed and discussed. This research proposal is important in optimizing the design life of the existing and aging offshore structures. Outcomes of this research are expected to provide a proper evaluation of the wave-in-deck mechanics and in return contribute to the current mitigation strategies in managing the issue.

Keywords: wave-in-deck loads, wave effects, water depth, fixed jacket platforms

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18 Digitalized Cargo Coordination to Eliminate Emissions in the Shipping Ecosystem: A System Dynamical Approach

Authors: Henry Schwartz, Bogdan Iancu, Magnus Gustafsson, Johan Lilius

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The shipping sector generates significant amounts of carbon emissions on annual basis. The excess amount of carbon dioxide is harmful for both the environment and the society, and partly for that reason, there is acute interest to decrease the volume of anthropogenic carbon dioxide emissions in shipping. The usage of the existing cargo carrying capacity can be maximized, and the share of time used in actual transportation operations could be increased if the whole transportation and logistics chain was optimized with the aid of information sharing done through a centralized marketplace and an information-sharing platform. The outcome of this change would be decreased carbon dioxide emission volumes produced per each metric ton of cargo transported by a vessel. Cargo coordination is a platform under development that matches the need for waterborne transportation services with the ships that operate at a given moment in time. In this research, the transition towards adopting cargo coordination is modelled with system dynamics. The model encompasses the complex supply-demand relationships of ship operators and cargo owners. The built scenarios predict the pace at which different stakeholders start using the digitalized platform and by doing so reduce the amount of annual CO2 emissions generated. To improve the reliability of the results, various sensitivity analyses considering the pace of transition as well as the overall impact on the environment (carbon dioxide emissions per amount of cargo transported) are conducted. The results of the study can be used to support investors and politicians in decision making towards more environmentally sustainable solutions. In addition, the model provides concepts and ideas for a wider discussion considering the paths towards carbon neutral transportation.

Keywords: carbon dioxide emissions, energy efficiency, sustainable transportation, system dynamics

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17 Anti-TNF: Possibilities of Rising Anti-Phosphorylcholine Antibodies

Authors: Md. Mizanur Rahman, Anquan Liu, Anna Frostegård, Johan Frostegård

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The role of the human immune system is essential in cardiovascular diseases and atherosclerosis. Activated cells in atherosclerosis produce abundant amounts of cytokines, but the exact mechanisms involved in the effects of these inflammatory cytokines are not clear in atherosclerosis. In a large clinical cohort, we have previously determined that antibodies against phosphorylcholine (anti-PC) are negatively and independently associated with both development of atherosclerosis and also a low risk of cardiovascular disease. Further, we reported that rheumatoid arthritis patients who were non-responders to TNF-inhibitors, where those with low anti-PC levels. Upon anti-TNF treatment, anti-PC levels increased. We, therefore, hypothesised that proinflammatory cytokines such as TNF could play a role in anti-PC regulation. Peripheral blood mononuclear cells (PBMC) were cultured with or without TNF and anti-TNF. The cell supernatants were collected after six days for ELISA measurements. In separate experiments, cells were cultured for 24 hours in both polystyrene plates and ELISPOT plates under a similar condition for ELISA and ELISPOT assays respectively. Total RNA was extracted after 6 hours of cell culture to perform RT-qPCR. Cell viability was confirmed by trypan blue staining and MTT assays. ELISA measurements detected less than 40% of anti-PC in TNF-treated cells, in comparison to control cells, whereas anti-PC production was recovered by anti-TNF treatment. ELISPOT assays showed that TNF suppresses anti-PC production by inhibiting anti-PC producing B-cells. In addition, RT-qPCR and ELISA showed that TNF also has effects also on B-cell activation as BAFF expression was inhibited by TNF treatment. Atherosclerosis is a major cause of cardiovascular diseases, but anti-PC is a protection marker for atherosclerosis development. Our findings show that TNF is a negative regulator of anti-PC production. Immune modulation and rising of anti-PC could be of major significance for the patients.

Keywords: anti-PC, Anti-TNF, atherosclerosis, cardiovascular diseases, phosphorylecholine

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16 The Cost of Non-Communicable Diseases in the European Union: A Projection towards the Future

Authors: Desiree Vandenberghe, Johan Albrecht

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Non-communicable diseases (NCDs) are responsible for the vast majority of deaths in the European Union (EU) and represent a large share of total health care spending. A future increase in this health and financial burden is likely to be driven by population ageing, lifestyle changes and technological advances in medicine. Without adequate prevention measures, this burden can severely threaten population health and economic development. To tackle this challenge, a correct assessment of the current burden of NCDs is required, as well as a projection of potential increases of this burden. The contribution of this paper is to offer perspective on the evolution of the NCD burden towards the future and to give an indication of the potential of prevention policy. A Non-Homogenous, Semi-Markov model for the EU was constructed, which allowed for a projection of the cost burden for the four main NCDs (cancer, cardiovascular disease, chronic respiratory disease and diabetes mellitus) towards 2030 and 2050. This simulation is done based on multiple baseline scenarios that vary in demand and supply factors such as health status, population structure, and technological advances. Finally, in order to assess the potential of preventive measures to curb the cost explosion of NCDs, a simulation is executed which includes increased efforts for preventive health care measures. According to the Markov model, by 2030 and 2050, total costs (direct and indirect costs) in the EU could increase by 30.1% and 44.1% respectively, compared to 2015 levels. An ambitious prevention policy framework for NCDs will be required if the EU wants to meet this challenge of rising costs. To conclude, significant cost increases due to Non-Communicable Diseases are likely to occur due to demographic and lifestyle changes. Nevertheless, an ambitious prevention program throughout the EU can aid in making this cost burden manageable for future generations.

Keywords: non-communicable diseases, preventive health care, health policy, Markov model, scenario analysis

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15 Begamat-I-Bhopals': Role in the Development of Female Education under Colonialism

Authors: Munaza Mubeen

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The colonial Urdu literature has played a significant role in uplifting the overall status of the Indians. Taking example of the Bhopal State, the contribution of the Royal ladies holds no match in the contemporary age. Similarly, the efforts of the Begamat-e-Bhopal in the field of education had been acknowledged across the Sub-continent. It had been noticed that with the downfall of the Mughal Empire at the hands of the British Raj, the local culture in the Indian sub-continent in general and in Bhopal State in proper got deteriorated. This led to uncertainty, chaos and an anti-British sentiment which created hatred against them in the entire sub-continent. Likely, in Bhopal State, the role of women in field of education also vanished. However, this change was felt by the ladies in the Royal Household where they struggled for restoration of the status quo with their personal efforts. The prominent contributors from the Royal household included Qudseya Begum, Nawab Sikander Begum, Nawab Shah Jahan Begum and Nawab Sultan Johan-they are known as Begamat-i-Bhopal. They established schools, colleges and universities to impart formal and non-formal education respectively. Their systematic approach and continued efforts constituted a dynamic aspect of women’ empowerment. Focused on the female education, however, one of the by-products of their efforts was an introduction of socio-cultural and politico-religious awareness among the middle class womenfolk. Unfortunately, the role of these Bagamat-i-Bhopal has been left untouched or ignored by the academic scholars. This study critically analyzed the role of Beghamat-i-Bhopal regarding female education in Hindustan in general and in Bhopal in particular. Similarly, the contribution of the contemporary writers in development of female education in Bhopal has also been discussed in this paper. This paper is based on the 'historico-textual' approach following structural reason which has established a justifiable argument. The researcher, therefore, has taken into consideration all the chronological nuances in order to accord greater visibility to the contents. The data has been described, analyzed and interpreted inclusively and in generalized manner.

Keywords: colonialism, Begamaat e Bhopal, female education, State of Bhopal

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14 Empirical Analysis of the Effect of Cloud Movement in a Basic Off-Grid Photovoltaic System: Case Study Using Transient Response of DC-DC Converters

Authors: Asowata Osamede, Christo Pienaar, Johan Bekker

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Mismatch in electrical energy (power) or outage from commercial providers, in general, does not promote development to the public and private sector, these basically limit the development of industries. The necessity for a well-structured photovoltaic (PV) system is of importance for an efficient and cost-effective monitoring system. The major renewable energy potential on earth is provided from solar radiation and solar photovoltaics (PV) are considered a promising technological solution to support the global transformation to a low-carbon economy and reduction on the dependence on fossil fuels. Solar arrays which consist of various PV module should be operated at the maximum power point in order to reduce the overall cost of the system. So power regulation and conditioning circuits should be incorporated in the set-up of a PV system. Power regulation circuits used in PV systems include maximum power point trackers, DC-DC converters and solar chargers. Inappropriate choice of power conditioning device in a basic off-grid PV system can attribute to power loss, hence the need for a right choice of power conditioning device to be coupled with the system of the essence. This paper presents the design and implementation of a power conditioning devices in order to improve the overall yield from the availability of solar energy and the system’s total efficiency. The power conditioning devices taken into consideration in the project includes the Buck and Boost DC-DC converters as well as solar chargers with MPPT. A logging interface circuit (LIC) is designed and employed into the system. The LIC is designed on a printed circuit board. It basically has DC current signalling sensors, specifically the LTS 6-NP. The LIC is consequently required to program the voltages in the system (these include the PV voltage and the power conditioning device voltage). The voltage is structured in such a way that it can be accommodated by the data logger. Preliminary results which include availability of power as well as power loss in the system and efficiency will be presented and this would be used to draw the final conclusion.

Keywords: tilt and orientation angles, solar chargers, PV panels, storage devices, direct solar radiation

Procedia PDF Downloads 135