Design And Analysis Of Three-To-Five-Phase Transformer For Multiphase Load

This research is focusing on a development of a multiphase transformer, or more specifically a three-to-five-phase transformer. The development of this transformer is based on the manipulation of the phasor diagram. The two input voltage phasors are added together in order to generate the output voltage on the secondary side of the three-to-five-phase transformer. The connection is modelled and validated in finite elements methods (FEM) software prior to the fabrication process. The performance of the developed three-to-five-phase transformer is analysed experimentally using No-load test and then followed by using two types of load; static resistance (R) and inductive (L) load and finally with the dynamic load. The No-load test is performed to verify the calculated phase to phase turn ratio, which in this case is 1: 1. Thus, the amplitude of the output voltage is equal to the input voltage. For the static load test, each phase of the transformer is connected to the R load and the RL load that connected in series. Then, the analysis of the three-to-five-phase transformer with dynamic load is conducted by using a five-phase squirrel cage induction motor. The developed transformer is supplying the motor that has been coupled with electromagnetic brake. The braking power of the electromagnetic brake can be increased or decreased by varying the variable DC voltage supply. This experiment has been carried out to represent the actual load as in the industrial machineries or equipment. Therefore, the successful of static transformation design is elaborated by using the simulation and experimentation method. The simulations result is capable to generate five-phase output and the five-phase induction motor under loaded condition is used to prove the viability of the transformation system. Finally, it is expected that the development of three-to-five-phase transformer can be used for drives application and may also be further explored to be utilized in power transmission system

Comparison on disinfection in water treatment system in conventional and ozonation system / Azizah Mohd Yusoff

Urbanisation and commercial development lead to higher demand of water. Public awareness and health conscious has given a task to Water Authority to enhance the quality of treated water. The challenged faced by Water Authority is the deteriorating of the sources of raw water from the rivers. The discovery and investigation has shown that chlorination practice in the conventional system has formed a chlorination by product of Thrihalomethanes (THMs). Experiment conducted on animal provided evidence of the carcinogenity of THMs. Through investigation conducted there is a correlation between the high usage of chlorine and the high formation of THM. In practice the highly polluted raw water needs higher concentration of chlorine in disinfection. In any treatment work disinfection is the most important processes. There are various type of disinfectant available and chlorine system has been used worldwide. This dissertation will discuss the comparison between chlorine in conventional system and a newly introduced system of ozonation in our country but has been used effectively in other countries. Selection of this system is due to the record of effectiveness evaluated. Discussion will be based on the effectiveness of both system and comparing the merit and demerit of both systems

Penjagaan akal menurut perspektif Islam dalam konteks maqasid syariah / Fadhilah Adibah Ismail … [et al.]

Kertas kerja konsep ini memfokuskan kepada kedudukan dan penjagaan akal menurut perspektif Islam dalam konteks maqasid syariah. Usaha atau pendekatan yang dapat menyuburkan fungsi akal manusia perlu sentiasa dilaksanakan seperti pemugaran budaya ilmu secara konsisten. Sebaliknya, perkara yang boleh merosakkan fungsi akal seperti penggunaan arak, dadah dan seumpamanya adalah dilarang. Selain itu, impak penggunaan gajet terhadap fungsi akal manusia turut dibincangkan. Penggunaan gajet di dalam Islam adalah tertakluk kepada batasan yang ditetapkan syarak iaitu selagi mana mendatangkan manfaat atau maslahah kepada pengguna. Sekiranya membawa kepada kemudaratan atau impak negatif yang boleh menjejaskan fungsi akal seperti kebergantungan dan ketagihan melampau, maka penggunaannya adalah dilarang. Kajian ini diharap dapat membantu pihak berkenaan dalam mengatasi penyalahgunaan gajet di kalangan remaja melalui pembinaan modul atau garis panduan bersesuaian yang bersifat komprehensif, seimbang dan praktikal

Oral Health-related Quality of Life Among Pregnant Women at Hospital Universiti Sains Malaysia

This cross sectional study aimed to determine oral health-related quality of life in pregnant women. A total of 100 pregnant women seen at the Obstetrics and Gynaecology Clinic at Hospital Universiti Sains Malaysia participated in this study. The short version of the Malaysian Oral Health Impact Profile (S-OHIP(M)) questionnaire with five-point ordinal scale that ranges from ‘never' to ‘very often' was used to assess the frequency of oral impacts during the previous 12 months. The majority of the respondents were Malay (96.0%), with a mean age of 29.9 years (SD 5.78). The highest education level attained by most respondents was post-secondary qualification or Diploma (39.0%). Some had formal tertiary education (27.0%). The majority of them were income earners (74.0%) and contributed to the household income. Half of the respondents were in their third trimester of pregnancy while the remaining half was either in the first or second trimester. The severity of impact experienced by the women, which is the mean S-OHIP(M) score was high at 10.43 (95% CI = 8.96, 11.90). The prevalence of impact, which is the percentage of respondents reporting ‘fairly often' or ‘very often' to one or more impacts, was 36.0%. Common impacts experienced by the respondents include feeling uncomfortable because food got stuck in between teeth or dentures (22.0%), feeling that oral health problems had caused bad breath (13.0%), and feeling shy because of problems with teeth, mouth or dentures (9.0%). The results also demonstrated that neither the severity nor the prevalence of impact was influenced by the women's socio-demographic background. This study concluded that pregnant women suffered from high impact of oral diseases that could affect their quality of lif

Oral health knowledge, practice and dental plaque maturity status of hearing-impaired children

Hearing impairment is an unseen handicapped that lead to communication barriers which might impede knowledge transfer. The aim of this study was to compare the oral health knowledge, practice and dental plaque maturity between hearing-impaired (HI) and normal children. A cross sectional study was conducted among children aged 7-14 years old. The HI children were recruited from a special school for the deaf while the normal children were from the primary and secondary schools in Bachok, Kelantan. The oral health knowledge and practice was assessed by face to face interview whilst the dental plaque maturity status was evaluated using GC Tri Plaque ID Gel™ (TPID). The data was analysed using IBM SPSS version 22. HI children had poor oral health knowledge and oral health practice compared to normal children (p<0.05). HI children had significantly more matured plaque compared to normal children with mean (SD) DPMS of 1.8 (0.57) and 1.3 (0.20), respectively (p<0.001). In conclusion, there were poor oral health knowledge, poor oral hygiene practice and high plaque maturity among HI children

The Impacts of Gadget Use on Maqasid Shariah in the Context of Mind Preservation: A study among UiTM Shah Alam Students

This paper focuses on 'The Impacts of Gadget Use on Maqasid Shariah in the Context of Mind Preservation: A study among UiTM Shah Alam Students'. One of the positive impacts of using gadgets is to increase awareness among respondents. Use of gadgets in Islam must, therefore, be subject to the restrictions of Islamic law. It is hoped that this study will help the relevant parties to address the abuse of gadgets by recommending the appropriate guidelines for the optimal, decisive, comprehensive, balanced and practical use of devices among adolescents from the Islamic perspective. Keywords: maqasid Shariah; mind preservation; gadgets; impact, mind function eISSN: 2398-4287© 2021. The Authors. Published for AMER ABRA cE-Bs by e-International Publishing House, Ltd., UK. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians/Africans/Arabians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning &amp; Surveying, Universiti Teknologi MARA, Malaysia. DOI: https://doi.org/10.21834/ebpj.v6iSI5.294

The direct power control of three-phase AC-DC converter under unbalance voltage condition

This paper has presents the integrated approach for three-phase PWM AC-DC converter for obtaining the symmetrical components under unbalanced supply condition. The input structures for conventional direct power control have been modified with three simpler sequence networks instead it coupled by a detailed three-phase system method. In the cases of an unbalanced three-phase system, it causes the presence of unbalanced current and voltages thus produce the negative components on the grid voltage. Otherwise, the unbalance voltage in a three-phase power system causes severe performance degradation of a grid-connected VSI. Therefore, the imbalance voltage can be resolved by separating from the individual elements of voltage and current into symmetrical components called as a sequencing network. Consequently, the input power is relatively improved during unbalanced condition. It proven through the measurement of Total Harmonic Distortion (THD) from the conventional direct power control in individual elements is much higher compared than it resolved in separate components. Therefore, three symmetrical components are necessary for imbalance supply condition to obtaining almost sinusoidal grid currents

Peranan kepimpinan transformasi terhadap motivasi pekerja di sebuah kerajaan tempatan di Johor

Kajian ini dijalankan untuk mengenalpasti hubungan di antara gaya kepimpinan transformasi penyelia terhadap motivasi pekerja di salah sebuah kerajaan tempatan di Johor. Berdasarkan kajian lepas, gaya kepimpinan ketua memberi pengaruh yang signifikan kepada motivasi pekerja di tempat kerja. Kajian ini merupakan kajian berbentuk deskriptif dan menggunakan borang soal selidik sebagai instrumen kajian untuk mengumpul data. Borang soal selidik tersebut mengandungi tiga bahagian utama iaitu Bahagian A (Latar Belakang Responden), Bahagiab B (Kepimpinan Transformasi) dan Bahagian C (Motivasi Pekerja). Responden kajian telah dipilih secara persampelan rawak mudah iaitu seramai 75 orang daripada salah sebuah kerajaan tempatan di Johor. Data yang diperolehi telah dianalisis menggunakan perisian Statistical Package for Sosial Science (SPSS) versi 22.0. Dapatan kajian menunjukkan bahawa kepimpinan transformasi mempunyai hubungan yang positif dan signifikan kepada motivasi pekerja (r=0.658). Ia bermaksud peranan ketua yang mengamalkan gaya kepimpinan transformasi dikenalpasti mampu meningkatkan motivasi pekerja untuk bekerja