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Soda lime silica (SLS) waste as the source of silica (SiO2) and ark clamshell (ACS) as the foaming agent has been utilized to fabricate the low-cost and lightweight foam glass-ceramics. A series of 1 and 6 wt% foam glass-ceramics were successfully prepared by the conventional solid-state sintering method at various sintering temperatures for 60 min. The bulk density of the samples has achieved minimum density (1.014 g/cm3) with maximum expansion (62.31%) at 6 wt% of the ACS content sintered at 800 °C for 60 min. The bulk density increases while the linear shrinkage and total porosity decrease with the progression of ACS contents and sintering temperature, where the results correspond with the FESEM micrograph. The result of XRD and FTIR transmittance spectra have shown that the formation of wollastonite crystal has occurred starting at 6 wt% of the ACS content sintered at 800 °C for 30 min. The highest mechanical performance (3.90 MPa) with an average total porosity (8.04%) is observed for the sample containing 1 wt% of ACS. It can be concluded that the composition of foam glass-ceramics (1 and 6 wt%) and sintering temperatures give significant results to the structural, physical, and mechanical properties of the fabricated foam glass-ceramics.

This study was conducted to synthesize foam glass-ceramic using SLS glass as a precursor; eggshell (ES) as a foaming agent and investigated the effect of sintering temperature on the crystal growth, microstructure and mechanical properties of the final product. The samples undergo the sintering process at different temperatures such as 700, 800 and 900 °C for 60 min with the heating rate of 10 °C/min. The structural properties were studied by XRD, FTIR and FESEM measurement. The cristobalite (SiO2) and wollastonite (CaSiO3) phases were identified after the sintering process and their microstructure was recorded by the FESEM micrograph. The physical properties of the samples were measured by average density measurement, linear expansion and compressive strength. The lowest density measurement using the Archimedes principle was achieved by 0.421 g/cm3 with the highest volumetric expansion at 92% after the sample sintered at 800 °C. Good correlations between porosity, mechanical strength and crystal phase were observed. The invention of foam glass-ceramics from waste materials can be applied as a potential building insulation material that gives benefit to the environment and energy usage.

For the very first time, a study on the crystallization growth of zinc silicate glass and glass-ceramics was done, in which white rice husk ash (WRHA) was used as the silicon source. In this study, zinc silicate glass was fabricated by using melt–quenching methods based on the composition (ZnO)0.55(WRHA)0.45, where zinc oxide (ZnO) and white rice husk ash were used as the raw materials. The control crystallization technique was used in which the sample was sintered at 700–950 °C; then, the physical, structural, and optical properties of the glass and glass-ceramics were investigated by using a densitometer, linear shrinkage, X-ray diffraction (XRD), Fourier transform infrared radiation (FTIR), field-emission scanning electron microscopy (FESEM), and photoluminescence spectroscopy (PL). The density and linear shrinkage increased as the crystallinity increased and the XRD results showed the progression of the crystal formation, in which the sample was still in an amorphous state at 27 °C and 700 °C; the crystalline phase started at 750 °C. Based on the FTIR spectra, all samples showed sharpened absorption bands as the sintering temperature was increased, and the FESEM image showed the progression of crystal growth, indicating the formation of zinc silicate glass-ceramics. Lastly, the PL spectra emitted three emission peaks, at 529, 570, and 682 nm for the green, yellow, and red emission, respectively.

Artificial neural networks (ANN) is known as one of the artificial intelligence tools which are inspired by the biological nerve system, have a capability to predict the physical and elastic parameter of glasses without melting the raw materials. The experimental of bismuth-tellurite glasses with the composition yBi2O3 - (1-y)TeO2 where y = 0, 0.05, 0.07, 0.10, 0.13, 0.15 have been fabricated using melting and quenching methods. These works were discovered that the prediction value by artificial neural networks for density, ultrasonic velocity, and elastic moduli of bismuth-tellurite glass composition gives a very good agreement as compared with the experimental measurements. The goodness of fit from the graph used R2 value to represent the relationship between the data presented from the experiment and prediction model. The great fit of coefficient R2 value elucidates in all figures is around 0.99942–1.0000 which is considered to be very satisfactory.

In this study, a nanocomposite of reduced graphene oxide (RGO) nanofiller-reinforcement poly(lactic acid) (PLA)/poly(ethylene glycol) (PEG) matrix was prepared via the melt blending method. The flexibility of PLA was improved by blending the polymer with a PEG plasticizer as a second polymer. To enhance the electromagnetic interference shielding properties of the nanocomposite, different RGO wt % were combined with the PLA/PEG blend. Using Fourier-transform infrared (FT-IR) spectroscopy, field emission scanning electron microscopy (FE-SEM) and X-ray diffraction, the structural, microstructure, and morphological properties of the polymer and the RGO/PLA/PEG nanocomposites were examined. These studies showed that the RGO addition did not considerably affect the crystallinity of the resulting nanomaterials. Thermal analysis (TGA) reveals that the addition of RGO highly improved the thermal stability of PLA/PEG nanocomposites. The dielectric properties and electromagnetic interference shielding effectiveness of the synthesized nanocomposites were calculated and showed a higher SE total value than the target value (20 dB). On the other hand, the results showed an increased power loss by increasing the frequency and conversely decreased with an increased percentage of filler.

A massive open online course (MOOC) is an example of an education evolvement as an online open course that is structured around a set of learning goals and facilitates the creation of learning community without restrictions. The aim of this chapter is to evaluate the effectiveness of deployment of four pilot MOOCs developed as part of the Malaysia MOOC initiative. Participants were first-year students in the first semester 2014/2015 from Malaysia HEI that registered for the four courses, Tamadun Islam dan Tamadun Asia (TITAS), Hubungan Etnik, Introduction to Entrepreneurship, and ICT Competency. Quantitative data was collected through a set of questionnaires filled out by a total of 4,449 first-year students. Collected data from the online survey were analyzed through descriptive analysis (frequency and mean). The results revealed that there are positive student insights on MOOCs’ curriculum, learning design, content quality, and impact on teaching and learning activities. However, the university spends less effort on the infrastructure, as the students depend only on the universities’ network connection. Hence, this initiative is promising, and MOOCs could potentially become “the” platform of teaching and learning in transforming education in the digital age.

Developing new absorbing and sheilding materials with a large band of frequency and high performance to allow the coexistence of the electronic components without the damaging electromagnetic interference (EMI) is needed. This paper is about the development of microwave-absorbing material from polycaprolactone by the addition of nickel oxide. Preparation of NiO/PCL composites to homogeneous were carried out using a Brabender Internal Mixer using the melt blend technique. These composites were characterized using Fourier transform infrared (FT-IR) spectrometry, scanning electron microscopy (SEM) as well using X-ray diffraction (XRD). Dielectric properties were obtained over a broad range of frequency of 8–12 GHz at the room temperature. It is found that the permittivity values increased via NiO filler content increments and decreased with frequency hikes. An instrument of rectangular waveguide is connected to a network analyzer (PNA) and the values of transmission (S21) and reflection (S11) parameters were measured which were also used for calculating reflection loss, microwave absorption values and the shielding properties of EMI by NiO/PCL composite at X-band frequencies. The measurement results found the material has good EMI shielding application potential as its microwave absorption has shown.

The impact of different sintering temperatures on physical, optical and structural properties of wollastonite (CaSiO3) based glass-ceramics were investigated for its potential application as a building material. Wollastonite based glass-ceramics was provided by a conventional melt-quenching method and followed by a controlled sintering process. In this work, soda lime silica glass waste was utilized as a source of silicon. The chemical composition and physical properties of glass were characterized by using Energy Dispersive X-ray Fluorescence (EDXRF) and Archimedes principle. The Archimedes measurement results show that the density increased with the increasing of sintering temperature. The generation of CaSiO3, morphology, size and crystal phase with increasing the heat-treatment temperature were examined by field emission scanning electron microscopy (FESEM), Fourier transforms infrared reflection spectroscopy (FTIR), and X-ray diffraction (XRD). The average calculated crystal size gained from XRD was found to be in the range 60 nm. The FESEM results show a uniform distribution of particles and the morphology of the wollastonite crystal is in relict shapes. The appearance of CaO, SiO2, and Ca-O-Si bands disclosed from FTIR which showed the formation of CaSiO3 crystal phase. In addition to the calculation of the energy band gap which found to be increased with increasing sintering temperature.

EZ Mind Map is a great presentation method which involves diagram or chart to summarize information, ideas, tasks or a solid description of the purpose of explaining a concept or idea. Meaningful learning is more easily achieved through mind map approach when new concepts are more specifically linked to the concept of a more general concept that has long been understood. Mind map involves diagram or chart is drawn to summarize information, ideas, tasks or a solid description of the purpose of explaining a concept or idea. Mind maps are used to improve memory through the subconscious mind. The main objective of this project is to review the use of EZ Mind Maps to improve student achievement, especially for students at the Faculty of Science, Universiti Putra Malaysia which has been implemented comprehensively through qualitative and quantitative approaches. The project is to study the effectiveness of learning through student achievement and assess the level of acceptance and suitability of using mind maps in the process of teaching and lifelong learning.

The integration of multimedia in teaching and learning process to occur more attractive way in form of the multimedia courseware, The aim of this study is to develop computer-based learning courseware for the field of electricity by using Microsoft Power Point powered by iSpring Suite 8 technology as development platform. A pre-test survey was conducted to 50 physics students to identify and analyze their problems in the field of Electricity before courseware was developed. The main goal of the development of this courseware is meant to strengthen students' understanding of the theories and concepts taught in this field. eSPRINT™ 4E is a physics courseware exclusive package consists of basics of electricity such as electric charge and fields, electric potential, electromagnetic induction as well as capacitance and dielectric. In order to evaluate the multimedia courseware developed based on respondents' perception, a post-test survey was conducted to 100 respondents who has enrolled the Physics courses. Generally, the average respondents' perception towards the developed courseware was positive. This present study showed that most of the student prefer to learn in interactive way such as through the courseware which is more fun and flexible. To conclude, the overall items in the survey have been interpreted positively by the respondents. eSPRINT™ is a registered trade mark No. 0600499 Class : (41) in Malaysia 30/03/2006.

Zinc silicate (ZnO–SiO2) systems were fabricated using zinc oxide (ZnO) and white rice husk ash (WRHA) with compositions of (ZnO)x(WRHA)1−x (

A series of ternary phosphate glasses in the form of (PbO)x(ZnO)60-x(P2O5)40 where x = 0–60 mol%, have been successfully prepared by conventional melt-quenching technique. The physical and elastic properties of the glasses have been investigated using pulse echo technique. The longitudinal and shear velocity of the glasses were measured using the MBS8000 ultrasonic data acquisition system at 10 MHz frequency in room temperature. The density, ultrasonic velocity and elastic moduli are found to be composition dependent and the correlation between the elastic moduli with the atomic packing density is discussed in detailed. The shielding parameters, mass attenuation coefficients, half value layers and exposure buildup factor (EBF) values have been computed using WinXCom program with the use of GP fitting method, and variation of shielding parameters are discussed for the effect of PbO addition into the glasses and photon energy. An increase in the density of the glasses results in a change in crosslink density. The sound velocity and elastic properties increased with PbO content and increase in Poisson's ratio trend suggests that the rigidity of the glasses has decreased. Besides, the replacement of ZnO by PbO causes an increase in mass attenuation coefficient, while the half value layer and the exposure buildup factor were decreased and these glasses has been potentially used as shielding material.

Zinc borotellurite glasses doped with lanthanum oxide were successfully prepared through melt-quenching technique. The amorphous nature of the glass system was validated by the presence of a broad hump in the XRD result. The refractive index of the prepared glass samples was calculated by using the equation proposed by Dimitrov and Sakka. The theoretical value of molar refraction, electronic polarizability, oxide ion polarizability and metallization criterion were calculated by using Lorentz-Lorenz equation. Meanwhile, expression proposed by Duffy and Ingram for the theoretical value of optical basicity of multi-component glasses were applied to obtain energy band gap based optical basicity and refractive index based optical basicity. The optical basicity of prepared glasses decreased with the increasing concentration of lanthanum oxide. Metallization criterion on the basis of refractive index showed an increasing trend while energy band gap based metallization criterion showed a decreasing trend. The small metallization criterion values of the glass samples represent that the width of the conduction band becomes larger which increase the tendency for metallization of the glasses. The results obtained indicates that the fabricated glasses have high potential to be applied on optical limiting devices in photonic field.

Er3+-doped tellurite glasses with molar compositions of xEr2O3-20ZnO-(80 - x)TeO2 (x = 0, 1, 2, 3, and 4 mole%) (EZT) have been successfully synthesized by the melt-quenching method. Density and molar volume have been measured. UV-VIS absorption spectra in the wavelength range of 400-800 nm at room temperature has been measured. The band gap for every composition has been calculated. Photoluminescence spectroscopy in the wavelength range of 400-650 nm and at room temperature has been evaluated.

Abundance of waste products disposed by communities has huge environmental impacts which lead to serious problems. Some waste products such as eggshells (ES) and soda lime silica (SLS) glass waste can be used as CaO and SiO2 resources to bring on new potentially CaSiO3, wollastonite glass ceramics (WGC) materials. Three samples labelled as S1, S2 and S3 with different compositions, each with of ES (15, 20, 25 weight%) and SLS glass (85, 80, 75 weight%) respectively, were prepared via solid state reaction method. All the samples were sintered at 800°C, 900°C and 1000°C. The elemental analysis of the raw materials and the WGC samples has been determined using the X-Ray Fluorescence (XRF) system where the experimental results show that the samples were mainly contained of CaO and SiO2. The density of the WGC samples increase linearly with the sintering temperatures. The XRD results reveal that the optimum crystalline phase of the WGC samples was at around 900°C.

Erbium zinc borotellurite, {[(TeO2)0.70(B2O3)0.30]0.7 (ZnO)0.3}1-y (Er3O2)y glasses were prepared by rapid melt-quenching method. The structural properties of the glass samples were determined by using x-ray diffraction (XRD) method and was confirmed its amorphous nature. The FTIR analysis shows that the Erbium Oxide increases the number of non-bridging oxygen that affects the bonding structure of TeO2, ZnO and B2O3. The absorption edge gives the value of band gap Eopt and Urbach energy ∆E. The value of Eopt lies between 3.025 eV and 3.440 eV for indirect band gap and between 3.500 eV to 3.680 eV in the direct band gap. The Urbach energy shows non-linear with the concentration of Erbium Oxide and varies within 0.153 eV and 0.200 eV.

Heavy metal oxide glasses, containing bismuth and/or lead in their glass structure are new alternatives for rare eart (RE) doped hosts. Hence, the study of the structure of these vitreous systems is of great interest for science and technology. In this research work, GeO2-PbO-Bi2O3 glass host doped with Er3+/Yb3+ ions was synthesized by a conventional melt quenching method. The Fourier transform infrared (FTIR) results showed that PbO and Bi2O3 participate with PbO4 tetragonal pyramids and strongly distort BiO6 octahedral units in the glass network, which subsequently act as modifiers in glass structure. These results also confirmed the existence of both four and six coordination of germanium oxide in glass matrix.

This manuscript reports on the physical properties and optical band gap of five samples of soda lime silicate (SLS) glass combined with zinc oxide (ZnO) that were prepared by a melting and quenching process. To understand the role of ZnO in this glass structure, the density, molar volume and optical band gaps were investigated. The density and absorption spectra in the Ultra-Violet-Visible (UV-Visible) region were recorded at room temperature. The results show that the densities of the glass samples increased as the ZnO weight percentage increased. The molar volume of the glasses shows the same trend as the density: the molar volume increased as the ZnO content increased. The optical band gaps were calculated from the absorption edge, and it was found that the optical band gap decreased from 3.20 to 2.32 eV as the ZnO concentration increased.

This paper reports the rapid melt quenching technique preparation for the new family of bismuth-lead germanate glass (BPG) systems in the form of (GeO2)60–(PbO)40−x–(½Bi2O3)x where x = 0 to 40 mol%. Their densities with respect of Bi2O3 concentration were determined using Archimedes’ method with acetone as a floatation medium. The current experimental data are compared with those of bismuth lead borate (B2O3)20–(PbO)80−x–(Bi2O3)x. The elastic properties of BPG were studied using the ultrasonic pulse-echo technique where both longitudinal and transverse sound wave velocities have been measured in each glass samples at a frequency of 15 MHz and at room temperature. Experimental data shows that all the physical parameters of BPG including density and molar volume, both longitudinal and transverse velocities increase linearly with increasing of Bi2O3 content in the germanate glass network. Their elastic moduli such as longitudinal, shear and Young’s also increase linearly with addition of Bi2O3 but the bulk modulus did not. The Poisson’s ratio and fractal dimensionality are also found to vary linearly with the Bi2O3 concentration.

The term ‘glass’ has a precise scientific meaning: a glass, or a substance in the glassy or vitreous state, is a material, formed by cooling down from the normal liquid state, which has shown no discontinuous change (such as crystallization or separation into more than one phase) at any temperature, but has become more or less rigid through a progressive increase in its viscosity. In common usage, the term ‘glass’ refers to a class of versatile materials of great practical usefulness, with a number of very characteristic properties which are typically hard and brittle solids, lustrous and often optically transparent. Glass is one type of amorphous solid material which also shows property of softening progressively and continuously when heated. The term is usually applied to inorganic solids and not to plastics or other organics. Glasses do not have crystalline (non-crystalline) internal structure. Its molecules have a disordered arrangement, but there is enough cohesion to produce rigidity. Majority of glass seen in everyday life is transparent, but glass can also be translucent or opaque. In science, however, the term glass is usually defined in a much wider sense, including every solid that possesses a non-crystalline (i.e. amorphous) structure and that exhibits a glass transition when heated towards the liquid state. The term ‘glass’ was developed in the late Roman Empire. It was in the Roman glassmaking center at Trier, now in modern Germany, that the late-Latin term glesum originated, probably from a Germanic word for a transparent, lustrous substance. Glasses can be made of quite different classes of materials. Glassy state, which is a universal property of supercooled liquids if they are cooled rapidly enough, is regarded as the fourth state of matter. The physics of glass is the science of the glassy or amorphous state of matter as seen from an atomic or molecular point of view. The mysterious glass transition phenomenon, which connects the liquid and glassy

A series of rare-earth phosphate glasses, (Gd2O3)x(P2O5)1-x with x= 0.222, 0.226, 0.229, 0.245 and (Tb2O3) x (P2O5) 1-x with x=0.226, 0.247, 0.263, 0.271 have been quantitatively studied. The room temperature of elastic moduli and Poisson’s ratio for each phosphate glass were estimated from the measured density and 15 MHz ultrasonic longitudinal and shear wave velocities. Previous experimental result shows the density and molar volume of gadolinium phosphate glasses increase as more Gd2O3 being added into the system. On the other hand, the density of terbium phosphate glasses increased however their molar volume has slightly decreases with an addition of Tb2O3. The decreases of both ultrasonic wave velocities in both glass series might be due to the microstructure and rigidity of glass network. The experimental result shows the longitudinal (L), shear (G) and bulk modulus (K) of both glasses decrease while the Young’s modulus increases as more Gd2O3 and Tb2O3 reside into the phosphate network. Theoretical elastic behaviour of both types of phosphate glasses have been quantitatively studied via the bond compression model (bc) and, Makishima and Mackenzie (m) model. Comparison between the experimental (e) and calculated theoretical elastic data of gadolinium and terbium phosphate glasses has also been carried-out. Analysis show that based on the bond compression model, as the mole fraction of Gd2O3 increase in the (Gd2O3)x(P2O5)1-x glass system, both ratio of Kbc/Ke and the atomic ring size slightly increase. However for (Tb2O3)x(P2O5)1-x glass system, the Kbc/Ke and atomic ring size decrease as Tb2O3 are added into the glass system. Based on Makishima and Mackenzie model, the elastic moduli for both glasses decrease due to the decreasing in packing density of glasses. For the bulk modulus, Km value slightly higher as compared to Ke and Kbc. The Poisson’s ratio shows a good agreement with the experimental and calculated values. The difference of variation pattern betw

Satu prototaip sistem pengurusan pembelajaran (LMS) berdasarkan Model Reka Bentuk Pemprototaipan Pantas telah dibangunkan. Persepsi pensyarah mengenai keperluan LMS bagi menyokong pembudayaan e-pembelajaran dan menilai penggunaannya telah dijalankan. Persepsi pensyarah terhadap e-pembelajaran dari aspek sikap, kemahiran teknologi dan juga bidang kepakaran dikaji bagi mengetahui keperluan pensyarah untuk menggunakan prototaip LMS tersebut. Kajian mendapati pensyarah amat positif terhadap perubahan-perubahan baru yang berlaku terutama pembangunan ICT di kampus. Persepsi pensyarah terhadap prototaip LMS yang dibangunkan mendapati mereka begitu positif dan bersetuju dengan reka bentuk antaramukaan dan navigasi dengan nilai skor min melebihi 3.50 bagi setiap item yang diberikan. Responden bersetuju dengan reka bentuk LMS yang mudah dengan teks dipersembahkan dengan jelasnya (min=4.10, sp=O.77), kejelasan ikon atau grafik (min=4.14, sp=0.64), arahan-arahan yang mudah untuk diikuti (min=4.10, sp=0.68) dan dapat meneroka LMS tersebut (min=4.10, sp=0.79) dengan mudahnya. Hasil kajian juga mendapati lebih 40 pensyarah (53%) yang mengamalkan kaedah SCL mengemaskinikan nota-nota kuliah sekurang-kurangnya sekali seminggu. Prototaip LMS telah berupaya menyediakan perkhidmatan sepertimana keperluan yang dikehendaki (min=3.35, sp=0.93) oleh pengguna. Bagi tujuan pengurusan bahanbahan pengajaran menerusi LMS, responden juga bersetuju bahawa amat mudah untuk memuat-naik (min=3.69, sp=0.82) dan memuat-turun (min=3.70, sp=0.80) dokumen-dokumen pengajaran. Secara keseluruhan responden bersetuju bahawa prototaip LMS tersebut yang mengandungi bilangan modul yang minimum amat begitu mudah untuk digunakan (min=4.04, sp=0.79) bersesuaian dengan tahap kemahiran ICT pensyarah.

Institusi Pengajian Tinggi(IPT) Malaysia harus berupaya untuk melaksanakan tanggungjawab sebagai penjana sumber manusia atau modal insan yang bukan sahaja berpengetahuan tetapi juga memiliki semua ciri insan kamil. Terkini, isu lambakan siswazah dan penganguran menjadi intipati perbincangan dengan menuding kepada institusi pengajian tinggi terutamanya IPT awam yang tidak peka kepada permintaan industri dan kurikulum yang kurang relevan dan ketinggalan sehingga graduan yang dihasilkan tidak memenuhi ekspektasi majikan. Sehubungan itu juga, keupayaan graduan dalam menangani kehidupan berkerjaya selepas menamatkan pengajian dipersoalkan kerana kekurangan kemahiran berkomunikasi, tiada sikap persaingan yang positif, tidak mampu melihat masalah sebagai peluang dan cabaran, selain dari tidak proaktif. Oleh itu, perhatian perlu diberikan dengan menilai dari akar umbi perubahan dan inisiatif yang perlu dilakukan bagi meraih semula kredibiliti IPTA yang tercalar dalam menyumbangkan modal insan yang bermutu dalam pembentukan pembangunan negara. Graduan yang dikeluarkan oleh IPT bukan sahaja mampu mencurahkan sumbangan di peringkat nasional tetapi mampu mendapat tempat di pasaran kerja antarabangsa yang sekaligus mampu menangani masalah pengangguran siswazah. Kertas ini melaporkan hasil dari bengkel Kemahiran Insaniah yang diadakan dengan tujuan memberi pendedahan dan latihan bagi dilaksanakan di IPT masing-masing.

With the help of social network analysis and the concept of 'community of practice', this paper reports on the patterns of interaction and participation of tutor and students discussion through computer-mediated communication (CMC). The descriptions cover the nature of participation; tutor-student and student-student interactions; the' nature of assisted performance; and the social network in the particular tasks. This paper offers an analysis of interaction patterns between tutor-student and student-student in different nature of tasks. Analysis shows that the pattern of assisted performance by a peer or the tutor could depend one or more of these factors: type of task (the nature of task initiated), group formation (either one whole big group or small working group) and the tutor management (the degree of tutor involvement in responding to students' posting).

Bismuth borate glass is of great interest in optoelectronic devices due to its low melting temperature (600–800 °C), extensive glass formation range, high refractive index ranging from 1.9 to 2.3, high physical and chemical stability, and nonlinear optical property. A systematic bismuth borate glass series in the systems of (Bi2O3)x−(B2O3)1−x have been successfully prepared by melt quenching technique over a wide range of composition (x = 35–70 mol%). Their elastic properties have been measured from their densities as well as longitudinal (VL) and shear ultrasonic wave velocities (Vs) which have been determined at room temperature by the MBS8000 Ultrasonic Data Acquisition system at a frequency of 5 MHz. The variation of ultrasonic wave velocities and elastic modulus such as longitudinal, Young's, bulk and shear modulus, Poisson's ratio, and micro hardness are discussed with respect of the Bi2O3 content.

The average cross-link density, number of the network bonds per unit volume, average stretching force constant, atomic ring size and the ratio Kbc/Ke have been calculated and discussed according to bond compression model for borotellurite glass. The result showed that the connectivity and rigidity of the borotellurite glasses increases with TeO2 content due to the transformation of BO3 units to BO4 and TeO3 units to TeO4. Comparison between theoretical calculated and experimental elastic moduli and Poisson's ratio has been carried out. The results showed good agreement between experimental and theoretical calculated elastic moduli.

e-learning is a process of integrating Information and Communication Technology (ICT) into the learning system that can be used by users without the limitation of time and location. The e-learning framework application known as Learning Management System (LMS) is capable in managing the teaching and learning processes effectively. Lecturers use LMS for the intention of increasing and enhancing the teaching-learning environment for the students with the diversity of learning resources available on the internet sites. The goal of this research is to develop an LMS that suits the ICT competency of lecturers and students in UPM. Meanwhile, the objectives of this research are to identify the lecturers’ perception on the necessity in developing the LMS in order to inculcate the culture of e-learning as well as to assess its usage among lecturers and students. Hence a prototype LMS based on the Rapid Prototyping Design Model has been developed. Lecturers’ perceptions toward e-learning from the aspects of attitude, skills in technology as well as fields of expertise were examined to identify the lecturers’ need to use the LMS prototype. The research found that lecturers are positive towards new changes that are happening especially in the campus ICT development. Overall, it was found that respondents have quite a high perception towards attitude (mean=4.03, sd=.76), technology skills (mean=4.19, sd=0.85) and field of expertise (mean=4.07, sd=0.93). The respondents perception is also positive mainly about the needs of LMS (mean=4.12, sd=0.80) and Learning Contents Management System (mean=4.11, sd=0.80) in their efforts toward e-learning accomplishment. The LMS prototype adopting open source PERL as the programming language has been successfully developed in which it took into account the aspects of data flow, database design, process design, navigation and interface design. The web based application is used by the lecturers to organize the learning materials, whereby the stu

The growing corncern of teachers to improve their theoretical classes together with the revolution and methods brought about by the new information technologies combine offering students a new attractive, efficient and agreeable form of learning. The case of Fundamental of Semiconductor Devices' is particularly special, since the main purpose of this project is to overcome the student's misconception on several topics of semiconductor devices and to develop an ebook of Semiconductor Devices. Graphical animated presentations were designed to provide a solution to overcome misconception. A pre-test and post-test were carried out, to monitor the student's performance before and after using the software. The significant different between pre-test 1 and post-test 1 (pilot test) with sigma value for post-test 1 with confidence interval of 0.000 «0.05). The results for posttest 3 (experimental treatment) gives similar sigma value as post-test 1. Meanwhile, the students' perception towards the courseware prototype is positive and inline with the applicable presentation of interface in mUltimedia with the meari score value excess of 4.16 (sd=0.76) for each items given. The results indicate that the software offers students a real life understanding of applicable concept.

A series of binary tellurite glass (TeO2)x(B2O3)1-x with x= 0.6-0.8 have been calculated using the bond compression model. The atomic ring size of the network has been obtained from the ring deformation model. The composition dependence of these parameters showed the elasticity and hence the respond of this glass system is influence by the chemical nature of tellurite dioxide composition. Variation of the estimated atomic ring size with ratio of the bond compression model Kbc to experimental Ke bulk modulus was studied to obtain more information about the structure of the glass. The result showed that the small value or the large value of Kbc/Ke are attributed to the very close (small ringed) three-dimensional network of these glasses.

Polycrystalline of (La1-xNdx)0.5Ba0.5MnO3 with x = 0, 1/6, 1/3, ½, 2/3, 5/6 and 1 has been prepared using solid state reaction. The effect of substituting neodymium at Lasite on magnetoresistance (MR) effect has been investigated. The doped samples are calcined at 900oC for 12 hours, pelletized and sintered at 1300oC for 24 hours. The magnetoresistance (MR) was measured at a magnetic field of H ≤ 1T at 90K, 100K, 150K, 200K, 250K, 270K and 300K. Overall, MR drops slowly when temperature rises. All doping concentration gives small variation range (~8.97% to ~63.49%). The highest MR value of 63.49 % was observed at 150K for sample of x = 1.0. The metal-insulator transition temperature, TP shifted towards lower temperatures as Nd doping increased, Tp followed by decreasing of the activation energy (Ea), which are 254, 244, 218, 198, 146, 130 and 114 K for the bulks with x = 0, 1/6, 1/3, ½, 2/3, 5/6 and 1, respectively. In the semi-conducting portion, activation energy (Ea) decreases as the doping concentration increases.

A series of glasses (TeO2)x (B2O3)1-x with x = 0.6, 0.63, 0.65, 0.70, 0.73, 0.75, 0.78 and 0.80 were synthesized by rapid quenching. Longitudinal and shear ultrasonic velocity were measured at room temperature and at 5 MHz frequency. Elastic properties, Poisson’s ratio and micro hardness have been calculated from the measured density and ultrasonic velocity at room temperature. Estimated parameters based on Makishima-Mackenzie theory and bond compression model were calculated in order to analyze the experimental elastic moduli. Comparison between the experimental elastic moduli data obtained in the study and the calculated theoretically by other models has been discussed.