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Using item option characteristics curve to analyze misconceptions on chemical reactions of pre-service chemistry teachers in Indonesia / Hilman Qudratuddarsi
No full textChemical reactions are an important component when studying chemistry but it is difficult to master them. The presence of three-level of representations (macro, sub-micro and symbolic) in chemistry add to this difficulty and as a result, misconceptions do take place. Misconceptions interfere with cognitive development of students and prevent them from having meaningful learning experiences. Thus, identifying accurately these misconceptions are paramount. These misconceptions are analysed using two-tier multiple-choice questions (2TMC). Some researchers argue its limiting diagnostic power and introduced three-tier and four-tier multiple-choice questions (3TMC and 4TMC). However, 3TMC and 4TMC have its own challenges in term of time and resources and is not very helpful in helping teachers to diagnose students‘ misconceptions. To counter this, researchers tried to enhance the diagnostic power of ordinary multiple-choice questions. This study aims to propose the use of item option characteristics curve (IOCC) to analyze strongest distractors to show misconceptions and promote 2TMC diagnostic power. The study was conducted by adopting the Representational Systems and Chemical Reactions Diagnostic Instrument (RSCRDI) and 185 Indonesian pre-service chemistry teachers participated in the study. The data was analysed using SPSS and Winstep software to create IOCC. The findings revealed, both IOOC and alternative answers for analysis using traditional method, showed comparable results, implying that using IOCC can detect pre-service chemistry teachers‘ misconceptions. In addition, IOCC analysis also highlighted aspects such as the unexpected curve after 0 logit of student measure, the inconsistency of alternative answers or distractor with the highest probability, and provided additional information to judge the strongest distractor to show misconceptions. The findings implied that distractor analysis using IOCC reveals information that are more detailed and richer, therefore has the ability enhance diagnostic power of 2TMC. This method is simpler and it allows teachers and students to diagnose their misconception to improve the quality of teaching and learning
Science teachers’ infusion of peer assessment in primary school / Usha Nair Tangaraju
No full textInfusing peer assessment strategies into science lessons have the potential to enhance learner autonomy. Learner autonomy is an important attribute as an educational outcome. Nevertheless, research indicates that teachers do not infuse peer assessment strategies that teachers perceive as challenges. Thus, this study examines how primary science teachers infuse peer assessment strategies and to investigate the challenges these teachers face when infusing these strategies. The exploratory qualitative research design was utilized. The sample of this study were three primary school science teachers. These teachers were chosen because of their willingness to participate in the study. Data collection techniques employed were classroom observations and interview sessions. Four classroom observations were done for each teacher. The data was analysed using episodes based on the classroom discourse where there was indication of infusing peer assessment strategies. The challenges of infusing peer assessment were obtained from the interview data. This data was analysed using thematic analysis. The findings revealed that the three teachers’ infusion of peer assessment strategies lies along a continuum. These infusion practices were labelled ‘impressive’, ‘intermediate’ and ‘inferior’. In the ‘impressive’ category, teachers allowed students to ask their peers questions and provided a safe environment to do so. In contrast, the practices in the ‘inferior’ category showed teachers’ classroom management as poor when they infused a certain kind of strategy. The teacher became the knowledge provider as teachers took over control without providing ample time for the student to immerse in the process. In the ‘intermediate’ category, the teachers did prepare resources to help students to mark their peer’s work independently, but the teachers were unsure of how to facilitate the process. The data obtained from the interview sessions elicited for four different challenges: Perceived pressure of time and work, Reluctance to change, Language proficiency and Routine and boredom. For example, the teachers did not believe that the infusion of peer assessment strategies could be sustainable because of the high demands of external examinations and stakeholders. Moreover, they claimed challenges such as non-active involvement from students, time constraints and wide syllabus may hamper the infusion of peer assessment strategies. The implication of this study is this study has highlighted the evidence of how much infusion of the peer assessment strategies are taking place in the classroom as well as the challenges teachers face in infusing these strategies. This should provide policy makers with relevant data when taking the next step in the school assessment reformation. Moreover, since peer assessment is a multifaceted enterprise, a more collaborative approach to infuse peer assessment strategies should be given priority. The move to effective peer assessment is not simple for teachers and students but is worthwhile and necessary for twenty-first-century learning
Mental workload investigation among employees in a selected oil and gas company / Christyne Surindai C. Moosom
Get PDFIn recent years, there has been a substantial amount of studies being conducted in mental workload and mental health but there is little research conducted in the Malaysian context especially in the oil and gas field. This gives rise to the need for researching the level of mental workload and mental health problems that will help the stakeholders to protect the wellbeing of their employees. This study aims to investigate the mental workload and level of depression, anxiety and stress scale of employees in a selected oil and gas company by using CarMen-Q and DASS-21 mental health assessment tools, finds the correlation between these parameters and propose recommendations to the company to improve the mental health of their employees. The mental workload statistical analysis revealed that the employees were highly burdened in performance demands (M=76.60) followed by cognitive demands (M=65.65), temporal demands (M=57.34) and emotional demands (M=48.78). 48.98% of employees were determined to have a normal score of depression., 63.27% has a normal score of stress and 18 (36.74%) has a normal score of anxiety. Significant findings reported that 12.24% have extremely severe depression and anxiety and 4.08% worker found to be extremely severe stressful working in the company. The level of depression, anxiety, stress and mental workload of the employees have significant correlations with each other of at least r=0.453. These findings have tailored the researcher to develop strategies for the company to curb mental health problems arising in the company based on the condition and nature of the business activities of the company
Inventory models for perishable items under markdown policy / Nurzahara Atika Kamaruzaman
Get PDFAs expected, the demand for a fresh product depends on how fresh it is, therefore, it is important to take expiration date into consideration. Based on marketing and economic theory, several factors such as price, inventory level and advertisement play a crucial role in influencing the demand. Hence, we study the effect of these factors in influencing the demand in the inventory model. Since the demand for perishable product declines over time, markdown policy is offered to increase the demand and profit while reducing the inventory. Salvage value is incorporated to the deteriorating units. In this research, we extend previous works and develop three inventory models for perishable items under markdown policy. We show that the markdown policy is an appropriate strategy to sell and get rid of slow-moving or remaining inventory when the season ends and increase the annual profit. Moreover, we find the best time to offer markdown strategy. We obtain the optimum solution with the help of numerical examples. Sensitivity analysis is presented to illustrate the effectiveness of each model
Polyhydroxyalkanoates for innovative electrodes and proton exchange membrane modification in microbial fuel cell / Sirajudeen Abdul Azeez Olayiwola
Get PDFThe increase in global energy demand due to increasing population and industrialization demands renewable and environmental-friendly alternatives. Energy from fossil fuel are non-renewable, depleting and detrimental from environmental perspectives. Alternative energy, green and renewable such as hydrogen fuel, biodiesel, bioethanol, microbial fuel cell and many more have been extensively investigated. One possible solution lies with non-combustion method such as microbial fuel cell. A microbial fuel cell is a sustainable and environmental-friendly device that combines electricity generation and wastewater treatment through metabolic activities of microorganisms. However, low power output from inadequate electron transfer to the anode electrode hampers its practical implementation. Nanocomposite of oxidized carbon nanotubes and medium-chain-length polyhydroxyalkanoates (mcl-PHA) grafted with methyl acrylate monomers enhances anode-cathode electrodes electrochemical function in microbial fuel cell. Extensive polymerization of methyl acrylate monomers within mcl-PHA matrix, and homogenous dispersion of carbon nanotubes within the graft matrix are responsible for the enhancement. Modified electrodes exhibit high conductivities, enhanced redox peak and reduction of cell internal resistance up to 76 %. A stable voltage output at almost 700 mV running for 225 hours generating maximum power and current density of 351 mW/m2 and 765 mA/m2 respectively. Superior biofilm growth on modified anode surface as well as enhanced redox peak of modified cathode are responsible for improved electron transfer to the anode and efficient oxygen reduction rate at cathode, hence stable and elevated power output generation. Polyhydroxybutyrate (PHB) as an integrated component of ion exchange membrane in microbial fuel cell (MFC) was also investigated. PHB crystals ranging from 5-15 % (w/w) were thermally dispersed and composited within medium-chain-length polyhydroxyalkanoate (PHA) matrix as shown by spectroscopic analyses. The composite membranes were juxtaposed with Nafion membrane for improved ion conduction. Membrane with 10 % and 15 % (w/w) PHB recorded two-fold maximum voltage potential compared to Nafion membrane alone. A power density of 601 mW/m2 was recorded for PHB 15% membrane, which was superior to Nafion membrane (520 mW/m2). In operation with real wastewater, maximum voltage potential, water uptake, power and current densities, chemical oxygen demand (COD) removal, ammoniacal nitrogen (NH3-N) removal, as well as coulombic efficiency (CE) recovery of the composite membrane are superior to Nafion; attributed primarily to high resistivity to oxygen molecules diffusion from cathode to anode compartments, which subsequently improved the overall MFC performance
Gene expression analysis of effectors involved in early interaction of banana and Fusarium oxysporum f. sp. Cubense / Poon Nee Kiew
Get PDFBanana is a popular but disease-laden fruit crop. It is very susceptible to various phytopathogens such as viruses, bacteria, fungi and nematodes. A particularly infectious and economically important fungal disease in banana is Fusarium wilt caused by Fusarium oxysporum f. sp. cubense (Foc). The disease has been plaguing the banana industry since late 19th century. Despite the early discovery of this phytopathogen of banana, little is known on its the mechanism of pathogenicity. In other plants, fungal effectors have been found to function in manipulating plant mechanisms during infection and many have been identified and characterized. In this study, the presence of a well-studied group of effectors known as Secreted-in-xylem (SIX) were verified in the Foc Tropical Race 4 (FocTR4) genome. Additionally, a computational pipeline was used to predict a pool of Foc effector candidates known as Small secreted cysteine-rich protein (SSCRP). The gene expression of selected effectors were characterized during the early interaction of the banana host and Foc. The in silico prediction pipeline successfully predicted 101 putative SSCRP and five of them were selected for gene expression analysis. The expression profiles of eight FocSIX genes identified in the genome were characterized with quantitative reverse transcriptase PCR (qRT-PCR). Four out of five SSCRP were found to be expressed in planta and all eight FocSIX genes were upregulated during early pathogenic interaction. Genomic features of the effector genes were also examined in this study. The results suggest FocSIX genes were actively involved in the early interaction of banana and FocTR4. Future work should focus on the functional characterization of the SSCRP and FocSIX encoding genes
Satisfaction of high-level athlete management in universities in Sichuan Province, China / Tang Yudong
Get PDFWith ongoing development in the construction of high-level sports teams in Chinese universities, the Chinese Ministry of Education is paying more and more attention to the running quality of high-level sports teams in universities. Evaluation of the construction quality of high-level sports teams in universities has received extensive attention from universities and society. However, for various reasons, the main body of high-level sports team evaluation comprises government agencies and universities, and, there is a lack of research on management systems of high-level athletes from the perspective of high-level athletes themselves. Therefore, it is of great theoretical and practical significance to develop a satisfaction model of high-level athlete management systems in Sichuan Province, while conducting empirical analysis from the perspective of high-level athletes.
The questionnaire used in this study consists of seven parts: expectations of high-level athletes, perceived management quality, perceived management value, satisfaction of high-level athletes, complaints of high-level athletes, loyalty of high-level athletes, and personal information. A panel of four experts were involved in determining the content validity of the initial questionnaire. Subsequently, five high-level athletes tested the surface validity of the questionnaire to assess whether it was easy to understand. Then, a pilot study was conducted with 83 high-level athletes, testing reliability and validity of the questionnaire, leading to the selection of appropriate items to form a formal questionnaire. In the main study, 327 high-level athletes completed the survey. Smart PLS 3 was used to complete evaluation of the measurement model and the structural model. Main factors affecting satisfaction of high-level athletes with their management systems were found through the application of IPMA. Through IPMA of latent variables of the model, it was found that among the three factors that affect satisfaction, perceived management quality needs to be improved first. However, IPMA based on sub-construction of perceived management quality showed that learning management, and training and competition management were both considered to be of the highest importance, yet were the least satisfactory of the five aspects of perceived management quality, and would need to be improved first.
The conclusions of this study found in this study that Sichuan universities should pay attention to evaluation of the satisfaction of high-level athlete management systems. Sichuan universities should begin improving the perception of management quality along with management value of high-level athletes. This should be followed by strengthening the publicity of high-level sports teams; improving the target orientation and expectations of high-level athletes; and improving the evaluation index system of high-level sports teams. The agenda should be to improve the management level of high-level athletes in Sichuan Province universities, thereby effectively improving the satisfaction and loyalty of high-level athletes, and enhancing the competitiveness of high-level sports teams in Sichuan universities
Multibeam array antenna for base station in the fifth-generation mobile communication system / Intan Izafina Idrus
Get PDFResearch on the fifth-generation (5G) mobile communication system has been accelerated to meet the standardization of the International Telecommunications Union for higher data traffic and higher data rates. The main requirements of the 5G mobile communication systems are the utilization of millimeter waves, the deployment of small cells, and the use of multibeam array antennas for multiple-input multiple-output schemes. Multibeam array antennas play an important role in developing a new base station to enhance system capacity, improve network coverage, and reduce co-channel interference. The main objective of this thesis is to design a single-layer multibeam array antenna at 28 GHz for base station in a 5G mobile communication system. The proposed multibeam array antenna is employed with a Butler matrix, which is the most promising solution for a 5G base station antenna. However, the literature has reported issues such as high amplitude imbalance and inaccurate phase differences between the output ports of the Butler matrix that cause the radiation characteristics to show incorrect main beam directions. To overcome these issues, a Butler matrix must have highly accurate dimensions to ensure the main beams point at the desired directions. This thesis presents the design of a multibeam array antenna with eight antenna elements fed by an 8 8 Butler matrix. The Butler matrix consists of sixteen crossovers, twelve quadrature hybrids, and eight phase shifters. The optimum design of each circuit element was obtained to form the 8 8 Butler matrix. A single-element microstrip antenna was designed to operate at 28 GHz. The microstrip antenna was integrated at each output port of the Butler matrix. The complete structure of a multibeam array antenna was simulated and optimized to obtain the desired radiation characteristics. Moreover, the beam coverage of the multibeam array antenna with different antenna spacing in the vertical plane was also studied and analyzed. The results show that the beam coverage was reduced as the antenna spacing increased. Additionally, the appearances of grating lobes were observed when the antenna spacing was increased to 0.7λ. Therefore, the multibeam array antenna with an antenna spacing of 0.6λ was selected for fabrication. The multibeam array antenna was fabricated using a low dielectric constant and low tangent substrate material named NPC-F220A. The results indicate that the 8 8 Butler matrix achieved a low insertion loss and a low phase error with average values of 2 dB and ± 10° at 28 GHz, respectively. The return losses of the multibeam array antenna were less than −10 dB, ranging from 27 GHz to 29 GHz. The main beams of the radiation pattern were pointed at ± 6°, ± 18°, ± 30°, and ± 44° with antenna gains between 9 dBi and 14 dBi. Furthermore, the configurations of multibeam base station antennas to achieve a 360° coverage area in the horizontal plane were presented. The beam coverage designs in the horizontal and vertical sectorizations were analyzed. The findings show that the proposed design concept of multibeam base station antennas is adequate and suitable for a 5G mobile communication system
Karya siri Sejadah Fatimah Chik mengikut konsep keindahan dalam Melayu / Ellina Maruti @ Ezani
Get PDFKajian tentang karya Siri Sejadah mengikut konsep keindahan Melayu ini bertujuan untuk mencapai objektif kajian iaitu memahami makna dan juga mesej yang terdapat dalam kesenian seni reka sejadah. Kajian yang berfokus kepada enam karya Siri Sejadah oleh Fatimah Chik dilaksanakan dengan menggunakan kaedah deskriptif kualitatif. Data dan informasi yang diperoleh melalui teknik pengumpulan data primer dan diperoleh dari data sekunder. Data dianalisis dengan menggunakan teknik analisis dengan menjadikan teori Konsep Keindahan dalam Melayu daripada Ruzaika Omar Basaree sebagai rujukan analisis. Hasil kajian menunjukkan bahawa kepentingan motif dan corak Seni Melayu adalah sesuai untuk diimplementasikan sebagai ragam hias pada sejadah. Kajian ini secara praktikalnya memberi sumbangan ke arah kepentingan seni Sejadah sebagai satu seni yang perlu dihargai dan diangkat secara ilmiah Hasil dari kajian ini boleh dijadikan sebagai satu rujukan ilmiah kepada karyawan muda yang baru berkecimpung dalam dunia seni visual. Malah kajian ini boleh dijadikan sebagai garis pandu kepada pereka-pereka khususnya dalam industri seni reka tekstil untuk menghasilkan seni sejadah yang mempamerkan identiti Melayu sebagai seni hiasan sejadah
Hand posture for beginner piano playing using plush toy assisted learning / Shugeshini Kumanan
Get PDFThis research paper explored the possibilities of using an animal plush toy as a tool to teach piano playing hand posture among participants formed by children age four up to six years old. The idea of Plush Toy Assisted Learning (PTAL) originates from AAL or animal assisted learning. Adopting a case study that involved a quantitative and a qualitative research framework, this research reveals an in-depth observation of a proposed new pedagogical idea in developing a proper hand posture using an animal soft toy as a tool towards children. Methodology includes a self-reflexive account of the researcher as a teacher via participant-observation, audit trail, log book, video recording, interaction between the child and the plush toy, comparison by interest and also the effectiveness of teaching approaches with or without the animal plush toy. The outcome shows that PTAL would be effective for younger children who are beginner piano player to learn their piano playing hand postures. This includes the duration of the process of learning and the effectiveness in applying the animal plush toy in replacing real-animal assisted learning to play the piano using a proper hand posture. Traits of pattern of \learning and also behavioural response in children towards the plush toy were discussed