bluuebunny/crossref_metadata_2025 huggingface dataset:
Pembentukan Sistem Pembangunan Proses (Process Development System) Melalui Proses Penambahbaikan di Kilang Lampin Pakai Buang
Authors: Saludin Mohamad Nasir , Abu Talib Mohamad Nizam
Published: January 2013

SSistem Pembangunan Proses (Process Development System) merupakan satu pendekatan kejuruteraan sistematik terkini untuk menganalisis masalah dan menambahbaik kualiti produk atau proses. Kajian ini hanya memfokuskan kepada masalah proses pengeluaran dan penambahbaikan ke atas proses pengeluaran lampin pakai buang (diaper). Kajian ini dilakukan ke atas salah satu mesin (Mesin Technipro) pembuat lampin pakai buang. Kombinasi kawalan proses statistik dan pendekatan lain seperti Kepner Tregoe, Poka Yoke, SMED, zero setting, centerlining, F1 Pit Shop dan rakaman video digunakan untuk melakukan penambahbaikan. Ukuran masa perjalanan mesin, masa mesin berhenti akibat mengalami kerosakan, masa penyelenggaraan mesin, peratus kecekapan mesin, peratus produk yang dihasilkan dalam sejam, peratus masa lengah mesin dan peratus kecacatan yang terhasil digunakan bagi membandingkan hasil dari proses penambahbaikan yang dijalankan. Kajian ini telah berjaya membangunkan dan mereka bentuk sistem pembangunan proses bagi memperbaiki proses-proses yang sedia ada.

Kata kunci: Sistem Pembangunan Proses, proses penambahbaikan, lampin pakai buang

Process Development System is a systematic engineering approach to analyze problems and improve the processes and product quality. This study focuses on the problem of diaper production processes and its improvements. For the case study, one dedicated machine (Technopro Machine) is selected. Combination of Statistical Process Control and other approaches like Kepner Tregoe concept, Poka Yoke concept, SMED concept, zero setting, centerlining, F1 Pit Stop concept, and video recording are used in the improvement process. The machine running time, machine downtime, preventive maintenance time, machine efficiency percentage, and product produced per hour are used to monitor the efficiency of the improved processes. This study is successful in developing and designing the Process Development System to improve the existing processes.

Keywords: Process Development System, process improvement, diaper
Effect of Porosity on Mechanical Properties of Metal Matrix Composite: An Overview
Authors: Aqida S. N. , Ghazali M. I. , Hashim J.
Published: January 2013

Keliangan di dalam tuangan komposit matriks logam (KML) adalah satu kecacatan yang boleh mempengaruhi kekuatan bahan terutamanya di dalam KML bertetulang partikel. Merujuk kepada kajian lepas, faktor-faktor pembentukan keliangan adalah berpunca daripada gelembung-gelembung udara yang memasuki leburan matriks logam, wap air yang terdapat pada permukaan partikel, gas yang terperangkap semasa proses pencampuran, evolusi hidrogen dan pengecutan tuangan semasa pemejalan. Namun, kebanyakkan kajian menunjukkan punca utama pembentukan keliangan adalah parameter proses tuangan. Kandungan keliangan yang paling minima akan menentukan sifat optimum tuangan KML. Secara umumnya, peningkatan kandungan keliangan akan mengurangkan sifat mekanikal KML seperti kekuatan tegangan, modulus Young, nisbah Poisson dan muatan redaman. Kesan pengurangan ini berlaku disebabkan oleh proses kegagalan yang berpunca daripada kehadiran lompang keliangan.

Kata kunci: Keliangan, tuangan kacau, sifat mekanikal, tuangan komposit matriks logam, silikon karbida

Pososity in cast metal matrix composite (MMC) has been known as a defect affecting the enhancement of strength, particularly in particle-reinforced MMC. From previous reviews, among the causes of porosity formation are air bubbles entering the melt matrix material, water vapour on the particles surfaces, gas entrapment during mixing process, evolution of hydrogen, and shinkage during solidification. Many studies had revealed that casting parameters are the main factors affecting porosity formation. Optimum properties of cast MMC are attained with least porosity content. Generally, increasing content of pososity will decrease the mechanical properties of MMC such as tensile strength, Young’s modulus, Poisson ratio, and damping capacity. This presence of porosity decreased the mechanical properties of cast MMC as the failure process is initiated from the voids formed.

Key words: Porosity, stir casting, mechanical properties, cast metal matrix composite, silicon carbide particle
Peningkatan Perkongsian Komponen Berdasarkan Kaedah Modular – Satu Kajian Kes
Authors: Abdullah A. B. , Ripin Z M. , Mokhtar M.
Published: January 2013

Pendekatan untuk meningkatan variasi produk pada kos yang murah daripada sumber yang terhad merupakan matlamat utama kebanyakan syarikat. Variasi produk boleh dipertingkatkan dengan pelbagai cara, antaranya perkongsian komponen. Dalam kajian ini, perkongsian komponen akan dipertingkatkan dengan menggunakan pendekatan modular. Secara umumnya, kaedah yang dicadangkan ini boleh dibahagikan kepada tiga fasa utama, iaitu pemodularan, mengenal pasti platform dan reka bentuk semula. Hasil kajian ini mendapati, perkongsian komponen dapat dipertingkatan dengan menggunakan pendekatan modular. Untuk menjelaskan metodologi yang digunakan, satu kajian kes terhadap keluarga produk kipas angin telah dijalankan.

Kata kunci: Variasi produk, perkongsian komponen, pendekatan modular, platform, reka bentuk semula

The application of product platform has been suggested as a key component of a well-targeted development strategy for companies that aim better utilization from limited resources. Product variants can be increased by several methods such as component commonality, In this paper, component commonality is increased using modular approach. Generally, this methodology can be divided into three phases; modularization, platform identification, and redesign. This study indicates that component commonality can be increased by using modular approach. To demonstrate the methodology, a case study on a family of domestic fans has been carried out.

Key words: Product variety, component sharing, modular approach, platform, redesign
Sistem Sokongan Perancangan (PSS): Analisis Aplikasi bagi Sektor-sektor Terpilih
Authors: Masron Tarmiji , Rainis Ruslan
Published: January 2013

Melaksanakan mekanisma pemantauan penting untuk memastikan setiap matlamat, dasar serta sasaran pembangunan dicapai oleh setiap Pihak Berkuasa Tempatan (PBT). Dengan itu jururancang bandar boleh merancang polisi-polisi yang bersesuaian, menilai kesan polisi dan dasar sebelum mengambil tindakan terhadap senario yang berlaku. Sistem Sokongan Perancangan (SSP) dibangunkan dengan aplikasi ArcView GIS dan Microsoft Access dengan menjadikan Maklumat Permohonan Kebenaran Merancang (MPKM) yang diterima oleh Jabatan Perancang, Pihak Berkuasa Tempatan (PBT) sebagai sumber data untuk mewujudkan petunjuk asas dalam proses pemantauan dan penilaian pelan perancangan di samping maklumat dari sumber-sumber lain. SSP menyediakan beberapa aplikasi asas dalam membantu jururancang dan pembuat keputusan memantau serta menilai pelan perancangan yang diguna pakai.

Kata kunci: Pemantauan Pelan Perancangan, Sistem Sokongan Perancangan (PSS), Maklumat Permohonan Kebenaran Merancang (MPKM)

Planning monitoring mechanisms are important to ensure that each development objectives, policies, and targets are achieved by Local Authorities (LA). As such, planners can plan suitable policies, and evaluate policy effects before actions against the current scenario are taken. Planning Support System (PSS) is developed by using the Arcview GIS and Microsoft Access applications, by turning Planning Approval Application Information received by the LA as data source in providing useful basic indicators, in monitoring and evaluating plans beside information from other sources. PSS provides several applications as well as basic abilities in assisting planners and decision makers in monitoring and evaluating planning plans.

Key words: Monitoring Planning Plan, Planning Support System (PSS), Planning Approval Aplication Information
Simulation of EDFA System Using EDFA_Design Software
Authors: Subramaniam T. , Harun S. W. , Mahdi M. A. , Poopalan P. , Ahmad H.
Published: January 2013

Kertas kerja ini mempersembahkan penilaian kebolehan perisian EDFA_Design dalam simulasi sistem EDFA. Hasil simulasi ciri-ciri EDFA seperti pancaran spontan berganda, gandaan, nilai hingar dan spektrum gandaan dibandingkan dengan hasil eksperimen yang sejajar. Perbandingan yang dibuat antara hasil simulasi dan hasil eksperimen menunjukkan bahawa nilai simulasi secara amnya mempunyai persetujuan yang baik dengan nilai eksperimen. Perbezaan yang timbul pada isyarat rendah dan kuasa pam tinggi adalah kurang daripada 1 dB. Walau bagaimanapun, dalam kawasan isyarat tinggi, perbezaan yang wujud meningkat kepada 2.6 dB dan merosot lagi di kawasan kuasa pam rendah. Pada keseluruhannya, perisian EDFA_Design ternyata merupakan satu alat yang berguna bagi simulasi ciri-ciri EDFA.

Kata kunci: EDFA, simulasi, EDFA_Design, penilaian

This paper presents the evaluation of the EDFA_Design software capability in simulating the EDFA system. Simulation results of the EDFA characteristics such as amplified spontaneous emission, gain, noise figure, and gain spectrum are compared with corresponding experimental values. The comparisons made between the simulation and experimental results show that the simulated values are generally in good agreement with the experimental values. The discrepancy in the low signal and high pump region is less than 1 dB. However, in the large signal region, this dicrepancy increases up to 2.6 dB and is worse in the low pump region. Overall, the EDFA_Design software proves to be a useful tool in simulating EDFA characteristics.

Keywords: EDFA, simulation, EDFA_Design, evaluation
Chain Code Algorithm in Deriving T–Junction and Region of a Freehand Sketch
Authors: Haron Habibollah , Shamsuddin Siti Mariyam , Mohamed Dzulkifli
Published: January 2013

Perwakilan kod rantai ialah salah satu daripada Bahasa Penghuraian Gambar yang digunakan untuk mewakili garisan. Kertas kerja ini menfokuskan kepada terjemahan lukisan garisan dengan menerapkan algoritma kod rantaai dalam mendapatkan dua entiti geometri, iaitu simpang–T dan kawasan, bagi lakaran lukisan garisan dua dimensi. Algoritma kod rantai tertutup ini mengandaikan bahawa lakaran mewakili objek padu tiga dimensi. Algoritma ini ialah berasaskan kod rantai Freeman 8–kaitan dalam tetingkap 3×3. Terdapat dua faktor yang menentukan kejayaan algoritma ini. Pertama ialah arah penjelajahan sama ada ikut jam atau lawan jam. Kedua ialah lokasi permulaan bagi penjelajahan dalam tetingkap 3×3 tersebut. Kertas kerja ini menerangkan faktor-faktor ini dan aplikasi mereka dalam mendapatkan entiti geometri tersebut. Perbincangan ini dibantu oleh contoh lakaran objek blok–L untuk memudahkan pemahaman terhadap algoritma. Kertas kerja ini diakhiri dengan kesimpulan dan cadangan pembaikan.

Kata kunci: Terjemahan lukisan garisan, kod rantaian, objek blok-L, Bahasa Penghuraian Gambar

Chain code scheme is one of the Picture Description Languages used to represent lines. This paper focuses on the line drawing interpretation by utilising closed loop chain code algorithm as a tool in deriving two geometric entities, i.e. T–junction and region, of a two–dimensional line drawing sketch. The closed loop chain code algorithm assumes that the sketch represents a three–dimensional solid object. The algorithm is based on 8–connected 3×3 windows of Freeman chain code. Two factors determine the success of the algorithm. The first factor is the direction of traverses either clockwise or anti–clockwise. The other is the start location of the 3×3 window traverse. This paper explains these factors and their applications in deriving the geometric entities. The discussion is supported with an example of L–block object for clarification in the presentation of the algorithm. This paper is concluded with conclusion and future works.

Keywords: Line drawing interpretation, chain code, L-block object, Picture Description Languages
Application of Multi Objective Fuzzy Linear Programming in Supply Production Planning Problem
Authors: Vasant Pandian M.
Published: January 2013

The objective of this paper is to establish the usefulness of modified s-curve membership function in a limited supply production planning problem with continuous variables. In this respect, fuzzy parameters of linear programming are modeled by non-linear membership functions such as s-curve function. This paper begins with an introduction and construction of the modified s-curve membership function. A numerical real life example of supply production planning problem is then presented. The computational results show the usefulness of the modified s-curve membership function with fuzzy linear programming technique in optimising individual objective functions, compared to non-fuzzy linear programming approach. Futhermore, the optimal solution helps to conclude that by incorporating fuzziness in a linear programming model through the objective function and constraints, a better level of satisfactory solution will be provided in respect to vagueness, compared to non-fuzzy linear programming.
Digital Front–End for Wideband Analog Front–End in a Multi–Standard Software Defined Radio Receiver
Authors: Puvaneswari M. , Sidek O.
Published: January 2013

Perisian tertakrif radio merupakan suatu konsep yang sedang memperoleh momentum bagi merealisasikan terminal radio wayarles berbilang mod, berbilang jalur dan berbilang piawai supaya dapat beroperasi mengikut pelbagai piawai komunikasi mudah alih yang berbeza. Kertas kerja ini menyelidik beberapa isu seni bina dalam mempertimbangkan hujung hadapan penerima beranalog bagi perisian tertakrif radio yang beroperasi untuk pelbagai piawai dengan objektif utama agar pemprosesan isyarat digit dikembangkan ke arah antena. Arkitektur hujung hadapan beranalog yang paling sesuai dipertimbangkan untuk mereka bentuk hujung hadapan berdigit dan implementasi dilakukan menggunakan terminal perisian tertaktif radio. Simulasi yang dilakukan menunjukkan spesifikasi piawai GSM dan DECT dicapai menerusi penukar rendahan kuadratur berdigit dan penapisan berbilang kadar yang diwakili oleh penapis bersisir tertib lima, penapis FIR sinc songsang dan penuras FIR umum. Suatu arkitektur reka bentuk titik tetap ditakrifkan dan implementasi yang efisien dalam mengurangkan penggunaan sumber perkakasan FPGA serta keputusannya dilaporkan.

Kata kunci: Penukaran analog ke digit, penapis FIR, pemodulat sigma delta, penukaran rendahan kuad, penapis berbilang kadar.

Software defined radio (SDR) is a concept that has been gaining momentum in realizing a wireless multi–mode, multi–band, and multi–standard radio terminal, capable of operating according to a variety of different mobile communication standards. This paper investigates a number of architectural issues and trade–offs involved in the consideration of receiver analog front–end for a multi–standard SDR with a fundamental objective of expanding the digital signal processing (DSP) towards the antenna. The most suitable analog front-end architecture is considered to design digital front–end and the implementation is done in a SDR terminal. The simulation undertaken demonstrated that GSM and DECT standards specifications are met by a multiplier less digital quadrature downconversion and multirate filtering composed of a 5th order comb filter, an inverse sinc filter and a generic FIR filter. A fixed point architectural design was defined and an efficient implementation in usage of FPGA hardware resource and the results are presented.

Keywords: Analog to digital conversion, FIR filters, sigma delta modulator, quadrature downconversion, multirate filtering
Stres Pekerjaan, Kepuasan Kerja, Masalah Kesihatan Mental dan Strategi Daya Tindak: Satu Kajian di Kalangan Guru Sekolah di Kota Kinabalu, Sabah
Authors: Chua Bee Seok
Published: January 2013

Kertas kerja ini bertujuan mengkaji sumber-sumber stres pekerjaan, strategi daya tindak, kepuasan kerja dan masalah kesihatan mental di kalangan guru. Seramai 140 orang guru sekolah rendah dan guru sekolah menengah di sekitar Kota Kinabalu, Sabah telah dipilih sebagai subjek kajian. Alat kajian yang digunakan adalah Occupational Stress Indicator (OSI) versi Bahasa Melayu. Tujuan kajian ini adalah untuk mengenal pasti sumber stres pekerjaan utama yang dialami guru sekolah berdasarkan jantina dan tahap sekolah. Tujuan kedua kajian ini adalah untuk melihat perbezaan antara guru lelaki dan guru perempuan, dan perbezaan antara guru sekolah rendah dan guru sekolah menengah dalam sumber stres pekerjaan, strategi daya tindak, kepuasan kerja dan masalah kesihatan mental. Tujuan ketiga kajian ini adalah untuk mengkaji pengaruh sumber-sumber stres pekerjaan ke atas kepuasan kerja dan masalah kesihatan mental dan tujuan keempat kajian ini adalah untuk mengkaji pengaruh strategi daya tindak dalam hubungan antara sumber stres pekerjaan dengan kepuasan kerja dan dalam hubungan antara sumber stres pekerjaan dengan masalah kesihatan mental serta pengaruh kepuasan kerja dalam hubungan antara sumber stres pekerjaan dengan masalah kesihatan mental.

Kata kunci: Stres pekerjaan, masalah kesihatan mental, kepuasan kerja, strategi daya tindak dan guru

The Occupational Stress Indicator (OSI) was adopted to investigate the source of stress, coping strategy, job satisfaction, and mental health problem among teachers. Data were collected from 140 primary and secondary school teachers in Kota Kinabalu, Sabah, Malaysia. The present study aims to identify the top ten sources of stress for teachers based on the demographic subgroups of teachers’ gender and level of school. This study also aims to examine the differences in sources of stress, coping strategy, job satisfaction, and mental health problem for the demographic subgroups of teachers’ gender and level of school. The study also examines the effect of sources of stress on job satisfaction and mental health problem. In addition, the effect of coping strategy and job satisfaction as a moderator in the relationship of the sources of stress and mental health problem was examined.

Key words: Occupational stress, mental health problem, job satisfaction, coping strategy and teacher
Konsep Kendiri dan Pencapaian Akademik Golongan Remaja: Melihat Sejauhmana Gaya Kepimpinan Ibu Bapa sebagai Moderator
Authors: Mad Shah Ishak
Published: January 2013

Kajian ini bertujuan melihat sejauhmana gaya kepimpinan ibu bapa menjadi moderator kepada hubungan antara konsep kendiri dengan pencapaian akademik remaja. Untuk mencapai objektif kajian ini, seramai 687 orang remaja yang belajar di tingkatan empat dan lima dari beberapa sekolah menengah kebangsaan di Johor Bahru dipilih sebagai subjek kajian. Instrumen Tennessee Self–Concept Scale yang dibina oleh Fitts dan Indeks Topologi Amalan Didikan oleh Baumrind digunakan untuk tujuan pengumpulan data. Data pencapaian akademik diambil dari peperiksaan akhir. Data yang telah terkumpul dianalisis menggunakan statistik deskriptif kecenderungan memusat untuk menganalisis latar belakang subjek kajian. Analisis kesan pemboleh ubah moderator ke atas hubungan pemboleh ubah bebas dengan pemboleh ubah terikat telah dilakukan menggunakan statistik infrensi regresi pelbagai. Keputusan kajian yang diperolehi menunjukkan gaya kepimpinan authoritarian dan autoritatif ibu bapa didapati hanya bertindak sebagai pengamal secara signifikan kepada hubungan antara konsep kendiri dan pencapaian akademik golongan remaja. Hubungan antara konsep kendiri dengan pencapaian akademik golongan remaja didapati bersyarat kepada gaya kepimpinan permisif ibu bapa.

Kata kunci: Konsep kendiri, gaya kepimpinan ibu bapa, pencapaian akademik

The objective of this study is to see parents’ leadership style as a moderator for adolescents’ self–concept and academic achievement realtionship. 687 adolescents who are studying in form four and form five from secondary schools in Johor Bahru have been choosen as research subjects. Fitt’s Tennessee Self–Concept Scale and Baumrind Parenting Topology Index were used as research instruments. Academic achievement data had been taken from their final examination results. Descriptive statistic had been used for analysing the research subject demographic’s data. The effects of moderator variable on the relationship of independent and dependent variables are analysed by multivariate regression. The result shows the parents’ authoritarian and autoritative leadership styles as a predictor for adolescent self–concept and academic achievement relationship. Whereas, the relationship of adolescents’ self–concept and academic achievement is conditional to parents’ permissive style leadership.

Key words: Self-concept, parents' leadership style, academic achievement
Stern Flap for Resistance Reduction of Planing Hull Craft: A Case Study with a Fast Crew Boat Model
Authors: Yaakob Omar , Shamsuddin Suhaili , Koh Kho King
Published: January 2013

Kajian terhadap pelbagai cara mengurangkan rintangan bot peronda telah dilakukan oleh ramai penyelidik. Kaedah yang dikaji termasuk penggunaan kepak buritan, baji buritan dan suntikan gelembung mikro. Walau bagaimanapun, disebabkan oleh sifatnya yang mudah dan praktikal, kepak buritan didapati amat berpotensi. Kertas kerja ini membentangkan kajian terhadap kesan kepak buritan terhadap prestasi rintangan bot kelasi berbentuk planing. Ujian model dijalankan bagi membuktikan keberkesanan kepak bagi mengurangkan rintangan. Lima kepak berlainan telah digunakan dalam rangka kajian sistematik bagi menentukan ciri geometrik optimum kepak buritan. Hasil ujian model menunjukkan empat kepak menambah rintangan kapal manakala kepak kelima pada sudut sifar mengurangkan rintangan sehingga 7.2 peratus pada 23 knots dan pengurangan purata sekitar 4.5 peratus. Pada 23 knots, pengurangan 8.2 peratus kuasa berkesan diperolehi.

Kata kunci: Reka bentuk bot peronda, ujian model, pesawat laju

The study on various methods of reducing the resistance of patrol craft have been carried out by many researchers. These methods included the application of stern flaps, stern wedges, and microbubble injection. However, due to its simplicity and practicality, stern flap is the most promising and cost effective method. The effect of a stern flap on the resistance performance of the planing hull crew boat is presented. Model tests were conducted to prove the effectiveness of the stern flap on reducing planing hull craft resistance. Five different stern flap designs were tested as part of systematic investigation to determine the optimum geometrical characteristics of the stern flap. Results of model resistance experiments showed that four of the flaps tested showed an increase in resistance while the flap at zero degree angle reduced the total resistance by 7.2 percent at 23 knots, and an average reduction rate of 4.5 percent. At 23 knots, an 8.2 percent reduction in effective power was predicted.

Key words: Patrol boats design, model testing, fast craft
Maximising Utility Savings Through Appropriate Implementation of Combined Heat and Power Scheme
Authors: A. Manan Zainuddin , Lim Fang Yee
Published: January 2013

Skema gabungan haba–kuasa yang juga dikenali sebagai kogenerasi telah diterima secara meluas sebagai salah satu daripada kaedah penjimatan tenaga yang amat berkesan, khususnya bagi loji proses kimia dari kategori industri sederhana dan besar. Terdapat dua kebaikan utama daripada skema gabungan haba–kuasa bagi sesebuah loji kimia: (i) bagi mengurangkan bil elektrik secara mendadak melalui penjanaan kuasa di dalam loji (ii) bagi menjimatkan bil bahan api melalui perolehan semula tenaga haba berkualiti yang terbazir daripada penjanaan kuasa untuk tujuan pemanasan proses. Untuk memastikan keberkesanannya, skema gabungan haba–kuasa perlu diintegrasi pada tahap suhu yang bersesuaian dalam konteks keseluruhan sistem proses. Kegagalan berbuat demikian akan menghasilkan skema gabungan haba–kuasa yang tidak akan mendatangkan sebarang manfaat. Kertas kerja ini menghuraikan kaedah implementasi yang berkesan untuk sebuah skema gabungan haba–kuasa berdasarkan satu kajian kes ke atas proses etil benzena. Sebuah teknik gambaran yang penting daripada kaedah analisis Pinch yang dikenali sebagai lengkuk rencam perdana telah digunakan sebagai panduan utama untuk integrasi optimum skema gabungan haba–kuasa dengan proses. Kajian ini menunjukkan bahawa integrasi bersesuaian di bahagian atas Pinch bagi skema gabungan haba–kuasa dengan proses etil benzena berpotensi menghasilkan penjimatan maksimum sebanyak 87% kos elektrik.

Kata kunci: Analisis Pinch, lengkuk rencam, lengkuk rencam perdana, kogenerasi

Combined Heat and Power (CHP) scheme, also known as cogeneration is widely accepted as a highly efficient energy saving measure, particularly in medium to large scale chemical process plants. The advantages of a CHP scheme for a chemical plant are two–fold: (i) to drastically reduce electricity bill from on–site power generation (ii) to save on fuel bills through recovery of the quality waste heat from power generation for process heating. In order to be effective, a CHP scheme must be placed at the right temperature level, in the context of an overall process system. Failure to do so might render a CHP venture worthless. This paper describes the procedure for an effective implementation of a CHP scheme using an ethyl benzene process as a case study. A key visualisation tool in Pinch Analysis technique known as the grand composite curve is used to guide CHP integration, and allows it to be optimally placed within the overall process scenario. The study shows that appropriate CHP integration with the ethyl benzene process above the pinch can potentially result in significant savings on electricity cost of up to 87%.

Key words: Pinch analysis, composite curves, grand composite curves, cogeneration
The Impact of Information and Communication Technology (ICT) in Users’ Interaction Between the Academic Staffs – Scientist/Engineers in Malaysia
Authors: A. Wahab Ahmadfauzi
Published: January 2013

Recent workplace studies claim that the latest advancements in Information and Communication Technologies (ICTs) and flexible work arrangements have enabled alternative ways of working that can now provide a wider scope of interactivity across geographic distances, a scope that would have once restricted interaction among groups, if not prohibited it altogether. Such claim has challenged the conventional understanding which asserts that proximity among firms provides crucial face-to-face interaction in the inter-organisation collaboration.
It is, however, debatable that the acceptance of the alternative workplace depends on the nature of the work, context, and culture of the organisation or nation. Therefore, this research examines the extent to which traditional locational assumptions and the proclaimed transformations performed in a developing country, such as Malaysia. The aim is to investigate the impact of university location – in terms of the characteristics of place and distance between places – to users’ face-to-face, and ICT interactions in the collaborations.
This research analysed a structured interview conducted with 32 academic staffs in two universities, and 25 scientists and engineers in 15 research organisations. The findings showed that face-to-face interaction has strong relationship with distance, and the impact of telecommunication technology in replacing face-to-face interaction is rather small.

Key words: ICT, face-to-face interactions, communication, location, distance, inter-organisation collaboration
Water Use Trend at Universiti Teknologi Malaysia: Application of ARIMA Model
Authors: Katimon Ayob , Demun Amat Sairin
Published: January 2013

Kertas kerja ini menerangkan aplikasi kaedah permodelan (ARIMA) bagi mewakili perilaku penggunaan air di kampus Universiti Teknologi Malaysia. Menggunakan fungsi–fungsi ACF, PACF dan AIC, siri masa penggunaan air bulanan di kampus UTM boleh dinyatakan dalam model ARIMA (2,0,0). Anggaran parameter model ø1 dan ø2 ialah 0.2747 dan 0.4194. Keadaan tersebut menggambarkan bahawa penggunaan air pada bulan semasa tidak semestinya dipengaruhi dengan tepat oleh kadar penggunaan air pada bulan sebelumnya. Analisis juga menunjukkan model ARIMA (2,0,0) boleh diguna sebagai model ramalan guna air di kampus universiti.

Kata kunci: Guna air, kampus universiti, siri masa, model ARIMA

The paper describes the application of autoregressive integrated moving average (ARIMA) model to represent water use behaviour at Universiti Teknologi Malaysia (UTM) campus. Using autocorrelation function (ACF), partial autocorrelation function (PACF), and Akaike’s Information Criterion (AIC), monthly campus water use series can be best presented using ARIMA (2,0,0) model. The estimated parameter of the model ø1 and ø2 are 0.2747 and 0.4194 respectively. This implies that water consumption in UTM campus at the present month is not necessarily influenced by water consumption of immediate previous month. Analysis shows that ARIMA (2,0,0) model provides a reasonable forecasting tool for campus water use.

Key words: Water use, university campus, time series, ARIMA model
The Residual Plot for a Non–Linear Regression Model with the Presence of Outliers and Heteroscedastic Errors
Authors: Midi Habshah , Jaafar Azmi
Published: January 2013

Regresi teguh adalah sangat berguna bagi menilai kecukupan satu penyesuaian dan mencadangkan penjelmaan yang sesuai. Ini boleh dicapai dalam hanya satu pelaksanaan penganggaran teguh dan bukannya membina satu diagnostik titik terpencil. Dalam kertas ini, prestasi plot reja bagi Penganggar Teguh MM Berpemberat (WMM) dibandingkan dengan plot reja Kuasadua Terkecil Tak Linear (NLLS), Kuasadua Terkecil Tak Linear Teritlak (GNLLS) dan Penganggar Teguh MM. Dari keputusan berangka yang diperoleh, menyatakan bahawa plot reja NLLS dan GNLLS sukar mengenal pasti titik terpencil dan titik pelarasan tinggi. Lagipun, ianya tidak menunjukkan corak impian dalam selang reja [–2.5, 2.5]. Plot reja GNLLS dan WMM menghasilkan corak impian apabila varian ralat adalah heterosedastik dan tiada kekotoran berlaku dalam data set. Plot reja dari MM boleh mengenal pasti titik terpencil tetapi reja dalam selang [–2.5, 2.5] menyatakan bahawa ianya menokok dengan menokoknya tindakbalas penganggar, yang mungkin memerlukan penjelmaan yang sesuai. Plot reja WMM mempamerkan corak impian unggul dengan rejanya yang bertaburan secara rawak di dalam selang [–2.5, 2.5].

Kata kunci: Titik terpencil, regresi teguh, heterosedastik, penganggar MM berpemberat

Robust regression is extremely useful in assessing the adequacy of a fit and suggesting appropriate transformations. This can be achieved in a single run by using robust estimation methods instead of constructing outlier diagnostics. In this paper, the performance of the residual plot of the robust Weighted MM estimators (WMM) was compared with the Non–Linear Least Squares (NLLS), Generalized Non–Linear Least Squares (GNLLS), and robust MM residual plots. The results obtained from numerical examples signified that the residual plots from the NLLS and the GNLLS fit can hardly identify outliers and high leverage points. Furthermore, it did not show an ideal pattern in the residuals within [–2.5, 2.5] interval. The GNLLS and the WMM residual plots revealed an ideal pattern when the error variances were heteroscedastic and no contamination occured in the data set. The residual plot from the MM fit can identify outliers but the residuals within the [–2.5, 2.5] interval indicated that the residuals increased with increasing estimate response, which may suggest an appropriate transformation. The WMM residual plot exhibited a pronounced ideal pattern denoted by its residuals, which were randomly distributed within [–2.5, 2.5] interval.

Key words: Outliers, robust regression, heteroscedastic, weighted MM estimator
Suatu Hubungan Kumpulan Pusat–2 dengan Teori Kebarangkalian
Authors: Sarmin Nor Haniza , Sapiri Hasimah
Published: January 2013

Penentuan darjah keabelanan bagi suatu kumpulan tak abelan telah diperkenalkan untuk kumpulan simetri oleh Erdos dan Turan [1]. Dalam tahun 1973, Gustafson [2] mengkajinya bagi kumpulan terhingga sementara MacHale [3] mengkajinya bagi gelanggang terhingga dalam tahun 1976. Dalam kajian ini, beberapa keputusan yang berkaitan dengan Pn(G), kebarangkalian bahawa suatu unsur rawak dengan kuasa ke–n dalam suatu kumpulan pusat–2 G adalah kalis tukar tertib dengan unsur rawak yang lain dalam kumpulan yang sama, akan diberikan. Seterusnya, batas atas bagi P2(G) diperoleh.

Kata kunci: Teori kebarangkalian, teori kumpulan, kumpulan terhingga, kalis tukar tertib

The determination of the abelianness of a nonabelian group has been introduced for symmetric groups by Erdos & Turan [1]. In 1973, Gustafson [2] did this research for the finite groups while MacHale [3] determined the abelianness for finite rings in 1976. In this research, some results on Pn(G), the probability that the n–th power of a random element in a 2–central group G commutes with another random element from the same group, will be presented. Furthermore, the upper limit of P2(G) is obtained.

Key words: Probability theory, group theory, finite group, commutative
Fractionation of Proteins in Surimi Waste Water Using Membrane Filtration
Authors: Tacharatanamanee Raweewan , Cherdrungsi Kitti , Youravong Wirote
Published: January 2013

The study was conducted to determine the feasibility of using ultrafiltration and microfiltration for fractionation of proteins in surimi waste water. The results from this study showed that the molecular weight of the soluble proteins in surimi waste water was in the range of 10–120 kDa. Ultrafiltration surimi waste water with using membrane with MWCO 100 and 300 kDa could not fractionate these proteins since most of the proteins were retained in retentate. This result suggested that fouling formed during ultrafiltration played an important role in determination of the membrane selectivity. Improving the fouling problem may be the key factor enhancing membrane selectivity. Fractionation of proteins from this waste by using microfiltration with membranes pore size 0.22, 0.45, and 1 μm was also studied. Although some proteins could penetrate through the membrane, the results from SDS–PAGE showed that the protein profiles in the retentate and permeates did not differ, indicating that these membranes also could not be used for fractionation. This may be due to the large pore size of the membranes and the narrow range of the molecular weight of these proteins.

Key words: Surimi waste water, protein recovery, fractionation, ultrafiltration, microfiltration
A New Short–Cut Design Method for Ultrafiltration and Hyperfiltration Cross–Flow Hollow Fiber Membrane Modules
Authors: Wan Daud Wan Ramli
Published: January 2013

Although ultrafiltration and hyperfiltration have replaced many liquid phase separation equipment, both are still considered as “non–unit operation” processes because the sizing of both equipments could not be calculated using either the equilibrium stage, or the rate–based methods. Previous design methods using the dead–end and complete–mixing models are unsatisfactory because the dead–end model tends to underestimate the membrane area, due to the use of the feed concentration in the driving force, while the complete–mixing model tends to overestimate the membrane area, due to the use of a more concentrated rejection concentration in the driving force. In this paper, cross–flow models for both ultrafiltration and hyperfiltration are developed by considering mass balance at a differential element of the cross–flow module, and then integrating the expression over the whole module to get the module length. Since the modeling is rated–based, the length of both modules could be expressed as the product of the height of a transfer unit (HTU), and the number of transfer unit (NTU). The solution of the integral representing the NTU of ultrafiltration is found to be the difference between two exponential integrals (Ei(x)) while that representing the NTU of hyperfiltration is found to be the difference between two hypergeometric functions. The poles of both solutions represent the flux extinction curves of ultrafiltration and hyperfiltration. The NTU for ultrafiltration is found to depend on three parameters: the rejection R, the recovery S, and the dimensionless gel concentration Cg. For any given Cg and R, the recovery, S, is limited by the corresponding flux extinction curve. The NTU for hyperfiltration is found to depend on four parameters: the rejection R, the recovery S, the polarization β, and the dimensionless applied pressure difference ψ. For any given ψ and R, the recovery, S, is limited by the corresponding flux extinction curve. The NTU for both ultrafiltration and hyperfiltration is found to be generally small and less than unity but increases rapidly to infinity near the poles due to flux extinction. Polarization is found to increase the NTU and hence the length and membrane area of the hollow fiber module for hyperfiltration.

Key words: Ultrafiltration; hyperfiltration; reverse osmosis; hollow fiber module design; crossflow model; number of transfer unit; height of a transfer unit
Characteristic of Co–Polyamide Nanofiltration Membrane: The Effect of Reaction Time
Authors: Ahmad A. L. , Ooi B. S. , Zulkali M. M. D. , Choudhury J. P.
Published: January 2013

Membran penurasan nano yang diubahsuai daripada polipiperazinamida telah dihasilkan dalam masa tindakbalas yang berbeza. Membran berkenaan dicirikan terhadap liang saiz dan ketebalan berkesan/keporosan dengan menggunakan model DSPM. Liang membran menjadi kecil pada permulaan tindakbalas disebabkan proses pengaitan bersilang tetapi liang saiz akan bertambah untuk jangkamasa tindakbalas yang lebih lama kerana kelemahan dinding liang membran. Walau bagaimanapun, nilai ketebalan berkesan/keporosan bertambah dengan masa dan menjadi stabil selepas 60s. Kesan masa tindakbalas terhadap liang saiz adalah tidak ketara berbanding dengan kesannya terhadap ketebalan berkesan/keporosan. Selama 2 minit tindakbalas, nilai ketebalan berkesan/keporosan untuk lapisan penapis berubah sebanyak 150%.

Kata kunci: Penurasan Nano, masa tindakbalas, saiz liang, ketebalan berkesan/keporosan

Modified polypiperazinamide nanofiltration membranes were fabricated under different reaction time. The membranes were characterized for its pore size and effective thickness/porosity using Donnan Steric Pore Flow Model. The pore size was reduced initially due to the crosslinking process but becomes larger at longer reaction time because of the weaker pores wall. On the other hand, the effective thickness/porosity grows with polymerization time and becomes constant after 60s. The effect of reaction time on the pore size is not as significant as effective thickness/porosity. Within 2 minutes of polymerization time, the effective thickness of the barrier layer would vary about 150%.

Key words: Nanofiltration, reaction time, pore size, effective thickness/porosity
Development of Cellulose Acetate Membranes for Nano–and Reverse Osmosis Filtration of Contaminants in Drinking Water
Authors: Bhongsuwan Darunee , Bhogsuwan Tripob , Buangam Narumol , Mangkalatas Waneerat
Published: January 2013

Cellulose acetate (CA) membrane was produced from CA powder, formamid, and acetone. Annealing temperature of 80C and evaporation times of 30, 60, and 90 seconds were chosen in preparation of the CA membranes named R530, R560, and R590, respectively. The membranes were tested using a dead-end stirred cell for filtration of NaCl salt, iron, manganese, and arsenic in the laboratory-prepared water and groundwater. Results of the tests using a membrane R530 at 400 psi showed, that the rejection efficiencies for salt, iron, and manganese in laboratory-prepared water with 3000 ppm NaCl , 2.0 ppm Fe, and 2.0 ppm Mn were 87%, 99%, and 92%, respectively, with a permeate flux of 21 Lm-2hr-1. Tests for the groundwater containing 4815 ppm NaCl and 5.48 ppm Mn without acid treatment showed that membrane R530 gave the flux and rejection for salt and manganese at 24 Lm-2hr-1, 85% and 98%, and for iron and manganese at 21 Lm-2hr-1, 93% and 99%, respectively. In the filtration of arsenic, the prepared membrane had a As rejection of 68 - 70% at 300 and 400 psi when the feed was the laboratory prepared 1 ppm As+3 contaminated water but it was found to be more than 82 - 96% when the feed was a natural water. This is probably because the prepared membrane had a higher rejection efficiency for As+5 ions than As+3 ions. Ion selective capability of the CA membrane shows the potential to use the membrane in filtration of selective ions.

Key words: Cellulose acetate membrane, reverse osmosis, nano-filtration, contaminated water, dead-end stirred cell
Measuring the Binding of an Antimicrobial Peptide with LPS by Fluoresence Correlation Spectroscopy
Authors: Yu Lanlan , Jeak Ling Ding , Wohland Thorsten
Published: January 2013

Antimicrobial peptides are an important defense weapon of many organisms, which attack the membrane of bacteria, leading to inhibition of bacterial growth and finally, bacterial death. Despite their ancient origin, it is difficult for bacteria to develop resistance against these peptides. This makes antimicrobial peptides a promising candidate for new drugs against microbial diseases. The target of these peptides is lipopolysaccharides (LPS), which are the major component of the outer membrane of Gram–negative bacteria. Known peptide structures and computational models show an amphipathic cationic pattern BHPHB (B: basic; H: hydrophobic; P: polar residue, respectively), which is the possible binding site of antimicrobial peptides to LPS. A cyclic amphipathic cationic 19–residue peptide (V4) with one disulfide bond has been designed (Frecer et al., unpublished data), which has potential antimicrobial activity. Circular dichroism measurements showed that V4 has a β–sheet structure. The interaction of a fluorophore labeled–V4 with LPS has been investigated by fluorescence correlation spectroscopy (FCS). The study demonstrated that V4 can specifically bind LPS, in contrast to zwitterionic phosphatidylcholine (PC) of eukaryotic cells. FCS makes it possible to study the binding between peptide and LPS at low concentration in vitro. The dissociation constant of the peptide and LPS was obtained using this technique.

Key words: antimicrobial peptides, LPS, peptide-lipid interaction, fluorescence correlation spectroscopy
Hubungan antara Nilai Kerja dan Faktor Demografi Guru Pelatih
Authors: Kasa Zakaria
Published: January 2013

Tujuan kajian deskriptif–korelasi ini ialah untuk menentukan sama ada terdapat hubungan yang signifikan antara nilai kerja dengan faktor demografi guru pelatih Universiti Putra Malaysia (UPM). Sebanyak 215 guru pelatih telah dipilih secara rawak sebagai sampel kajian. Seratus tujuh puluh tiga (80.5%) responden telah mengembalikan soal selidik. Dapatan menunjukkan bahawa secara keseluruhan responden mempunyai nilai kerja yang positif. Nilai kerja yang dianggap penting oleh responden ialah perkembangan kendiri, ganjaran ekonomi, pekerjaan yang terjamin, stail hidup dan kreativiti. Nilai kerja yang dianggap kurang penting ialah kepelbagaian, autoriti, hubungan sosial, risiko dan prestij. Hubungan rendah yang signifikan wujud antara nilai kerja secara keseluruhan dengan pengalaman mengajar dan umur. Jantina didapati mempunyai hubungan rendah yang signifikan dengan autoriti dan kreativiti. Pengalaman mengajar mempunyai hubungan rendah yang signifikan dengan prestij, kepelbagaian dan risiko. Taraf perkahwinan mempunyai hubungan rendah yang signifikan dengan risiko. Umur didapati mempunyai hubungan rendah yang signifikan dengan autonomi, stail hidup, prestij dan risiko. Cadangan yang diberikan ialah pendidik guru perlu membimbing guru pelatih dalam memilih laluan kerjaya yang sesuai dengan nilai kerja mereka dan pihak Kementerian Pelajaran boleh menggunakan nilai kerja guru pelatih sebagai kriteria dalam pemilihan guru.

Kata kunci: Nilai kerja, etika kerja, guru pelatih, sikap kerja, pendidikan perguruan

The purpose of this descriptive–correlational study is to determine whether there is a significant relationship between the work values and the demographic factors of trainee teachers in Universiti Putra Malaysia (UPM). A total of 215 trainee teachers were randomly selected as a sample of the study. One hundred and seventy–three (80.5%) respondents returned the questionnaires. The findings showed that generally, respondents had positive work values. Work values that were considered important by the respondents were self–development, economic rewards, job security, life style, and creativity. Work values that were considered by respondents as less important were variety, authority, social relations, risks and prestige. A low but significant relationship existed between the work values in general, teaching experience, and age. Gender was found to have a low but significant relationship with authority and creativity. Teaching experience had a low but significant relationship with prestige, variety, and risks. Marital status had a low but significant relationship with risks. Age was found to have a low but significant relationship with autonomy, life style, prestige, and risks. This study suggests that teacher educators should guide trainee teachers in choosing career paths that are suitable with their work values, and the Ministry of Education can use the work values of trainee teachers as a criteria in selecting teachers.

Key words: Work values, work ethics, trainee teacher, work attitude, teacher education
Analisis Kecerdasan Pelbagai (Multiple Intelligences) di Kalangan Pensyarah di Sebuah Institusi Pengajian Tinggi (IPT)
Authors: Ariffin Siti Rahayah , Mohd. Meerah T. Subhan , Othman Norasmah , Mohamed Zin Ibrahim
Published: January 2013

Konsep Kecerdasan Pelbagai (KP) atau Multiple Intelligences telah tersebar secara meluas di institusi pendidikan seluruh negara melalui siri–siri kursus semakan semula kurikulum di kolej dan institusi pengajian tinggi. Kajian lepas menunjukkan seseorang individu yang mempunyai IQ (Kecerdasan Intelek) yang tinggi tidak semestinya berjaya dalam kerjaya mahupun kehidupan peribadi. Selain IQ, setiap individu mempunyai kecerdasan lain yang penting dalam menyelesaikan masalah kehidupan manusia. Kajian ini bertujuan untuk mengenal pasti kecerdasan lain yang disebut sebagai kecerdasan pelbagai di kalangan 51 orang ahli akademik di sebuah institusi pengajian tinggi. Kajian ini menggunakan instrumen Multiple Intelligences Checklist for Adults (MICA) yang mengandungi 49 item bagi mewakili tujuh domain kecerdasan pelbagai. Dapatan kajian menunjukkan kebolehpercayaan (Cronbach Alpha) item–item adalah antara .68 – .84. Domain KP yang dominan ialah verbal–linguistik dan intrapersonal. Korelasi antara domain–domain menunjukkan juga verbal–linguistik dan intrapersonal yang paling kukuh. Analisis regresi berganda menunjukkan kecerdasan visual–ruang menyumbang sebanyak 55.3% kepada kecerdasan interpersonal.

Kata kunci: Kecerdasan pelbagai, analisis item, kebolehpercayaan, ahli akademik