High Dimensional Modulation and MIMO Techniques for Access Networks

Exploration of advanced modulation formats and multiplexing techniques for next generation optical access networks are of interest as promising solutions for delivering multiple services to end-users. This thesis addresses this from two different angles: high dimensionality carrierless amplitudephase (CAP) and multiple-input multiple-output (MIMO) radio-over-fiber (RoF) systems. High dimensionality CAP modulation has been investigated in optical fiber systems. In this project we conducted the first experimental demonstration of 3 and 4 dimensional CAP with bit rates up to 10 Gb/s. These results indicate the potentiality of supporting multiple users with converged services. At the same time, orthogonal division multiple access (ODMA) systems for multiple possible dimensions of CAP modulation has been demonstrated for user and service allocation in wavelength division multiplexing (WDM) optical access network. 2 x 2 MIMO RoF employing orthogonal frequency division multiplexing (OFDM) with 5.6 GHz RoF signaling over all-vertical cavity surface emitting lasers (VCSEL) WDM passive optical networks (PONs). We have employed polarization division multiplexing (PDM) to further increase the capacity per wavelength of the femto-cell network. Bit rate up to 1.59 Gbps with fiber-wireless transmission over 1 m air distance is demonstrated. The results presented in this thesis demonstrate the feasibility of high dimensionality CAP in increasing the number of dimensions and their potentially to be utilized for multiple service allocation to different users. MIMO multiplexing techniques with OFDM provides the scalability in increasing spectral effciency and bit rates for RoF systems. High dimensional CAP and MIMO multiplexing techniques are two promising solutions for supporting wired and hybrid wired-wireless access networks

Characterisation of pectins extracted from different parts of Malaysian durian rinds

Durian rinds are a potential source of pectin. The rinds consist of the outer layer of the fruit which is semiwoody and thorny and the inner layer, which is creamy white. Pectin may be present in varying amounts in different parts of the rind. Previous studies only investigated pectin content from the inner part of the rinds. Therefore, it is essential to provide scientific data on the pectin yield from whole durian rinds (including the thorns). Particularly, this information can be useful when preparing durian rinds for pectin extraction

A model of sustainable campus operations for Malaysian public universities

Currently, various initiatives have been undertaken by several universities around the world to ensure that their campus operates sustainably. Unfortunately, it seems that the efforts are still divergent and not systematically applied within the universities. Several models are available to be used as references for developing and implementing sustainability within campus. However, for local universities in particular, it is extremely important to understand the current situation whether there is a dearth of adequate conditions for the establishment and compliance of all phases of the models. As the issues of sustainability in Malaysia are still new, sustainability in universities should be performed in rather small steps according to the needs and situation of the university itself. Therefore, this study focuses on identifying the relevant Sustainable Campus Operation (SCO) initiatives to be implemented at the Malaysian public universities, and also determining the critical factors of governance that influence the successful implementation of the SCO initiatives. The investigation involves a quantitative approach using structured questionnaire survey, which was designed based on the items obtained from websites of sustainable universities around the world and also from literature review. The questionnaire survey forms were distributed to sixty-eight selected respondents at the Development Office or Sustainable Department of all local public universities. Based on the structural relationship model, it was found that the factor’s group of “Accountability to improve performance of SCO (AccF)” has the highest impact and more significant in implementing the thirteen relevant SCO initiatives as compared to the factor’s group of “Governance support to implement SCO (GovF)”. The established SCO model is the first that integrates all operations at the university, and highlights the importance for considering the governance support and accountability in analyzing and making decision of any potential initiatives towards campus sustainability. Hence, it can assist those involved in the planning of campus infrastructure and development to determine the most critical factors in implementing the SCO initiatives towards sustainability in Malaysian public universities

Extraction and characterization of low methoxyl pectin from durian rind

Durian is a tropical fruit in Southeast Asia. Durian rind, comprising 65-70% of durian total weight, may serve as a potential source of pectin, a gelling agent commonly used in the food and pharmaceutical industries. This study aims to optimize the pectin extraction from durian rinds and characterize its physicochemical and rheological properties. The factors affecting pectin extraction: durian rind parts and varieties, acid type and concentration, temperature, duration, and solid-to-liquid ratio (S:L) were screened and optimized based on yield, esterification degree (DE), and purity (AUA). Pectin was characterized by intrinsic viscosity, molecular weight, structural, thermal, morphological, and rheological analysis. The durian rind's white part has higher pectin yield than the rind with thorns, while variety D168 has lower yield than other varieties. The parts and varieties did not significantly affect DE and AUA. Pectin yield and DE deteriorated at higher acid concentrations (0.1, 1.0 M). Mineral acids (hydrochloric, sulphuric, and nitric acids) were more effective in extracting pectin of higher purity (AUA > 65%). Organic acids-extracted pectins (citric, acetic, and tartaric acids) had AUA < 65%, indicating poor purity. 0.001M sulphuric acid was selected for extraction optimization due to its good yield (9.13%) and purity (AUA = 66.72%) of lowmethoxyl pectin (LMP) (DE = 20.11%). According to response surface methodology, temperature was the most significant variable affecting yield and purity. DE was not pronouncedly affected by temperature (75 – 95 ℃), time (30 – 270 minutes), and S:L (1:20 – 1:60 g/mL). The optimal extraction conditions (93.3 ℃, S:L 1:50, 185 minutes) yielded 12.12% pectin with AUA = 77.01%, DE = 18.99%, intrinsic viscosity = 148.74 mL/g, and molecular weight = 42.12 kDa. The strongest gel was obtained with 3% (w/v) pectin at pH 3, showing better gel strength than commercial LMP. The gel showed good thermal stability throughout heating and cooling. Therefore, durian rind is a potential LMP source, which could be a gelling and thickening agent for weakacid- low-calorie food and pharmaceutical applications. Future studies could be done to explore durian rind pectin’s applications in the pharmaceutical and food industrie

Characterisation of pectins extracted from different parts of Malaysian Durian rinds

Durian rinds are a potential source of pectin. The rinds consist of the outer layer of the fruit which is semiwoody and thorny and the inner layer, which is creamy white. Pectin may be present in varying amounts in different parts of the rind. Previous studies only investigated pectin content from the inner part of the rinds. Therefore, it is essential to provide scientific data on the pectin yield from whole durian rinds (including the thorns). Particularly, this information can be useful when preparing durian rinds for pectin extraction. Hence, this study aims to examine and compare the yield and characteristics of pectin extracted from the inner part (W-I) and whole durian rind (W-H). The results indicate that the pectin yield from W-I was significantly higher (23.97%) than that obtained from W-H. The characterisation results show that both pectins have similar characteristics. The pectins extracted from W-I and W-H were high methoxyl pectin (HMP) with degrees of esterification (DE) at 53.13% and 51.42% respectively. The purity of these pectins was comparable to that of commercial pectins. These findings could pave the way in achieving sustainable pectin production at an industrial scale

Screening the physicochemical properties of thermosonically treated pomelo juice

Pomelo (Citrus grandis L. Osbeck) tastes sweet, slightly acidic with a hint of bitterness. It has many beneficial health effects. The aim of this study was to evaluate the effect of thermosonication treatment on physicochemical properties of pomelo juice by subjecting the juice to different times and temperatures. Thermosonication is a treatment where ultrasound is conducted at moderate temperature ranging between 37 and 75°C. Pomelo juice was treated with thermosonication for 2, 46 and 90 minutes with initial temperature ranging from 20C, 35C and 50C. The treated juice were analysed for its physicochemical properties, such as colour values (L*, a* and b*), total soluble solids (TSS) content, pH, titratable acidity and electrical conductivity. Results showed that the lightness (L*), pH, titratable acidity and electrical conductivity of the pomelo juice does not changed during treatment. However, redness (a*) and yellowness (b*) and TSS showed highest reading at 50C at 90 minutes

Kesediaan guru sekolah menengah mengamalkan pengajaran abad ke-21

Pendidikan pada Abad ke-21 menuntut setiap guru dan pelajar menguasai pelbagai bidang ilmu untuk bersaing dengan ledakan teknologi dan cabaran dalam era globalisasi. Walaupun proses pengajaran dan pembelajaran merupakan proses hakiki bagi seorang guru, namun cabaran di dalam abad ke-21 tidak boleh dipandang sepi. Ledakan teknologi maklumat di dalam bidang pendidikan memerlukan guru-guru turut sama menguasainya sama ada dengan rela atau terpaksa. Kajian ini bertujuan untuk mengenal pasti kesediaan guru mengamalkan Pengajaran Abad Ke-21 di SMK Dato' Sri Amar Diraja, Muar dari aspek literasi, kemahiran dan sikap. Selanjutnya, mengenal pasti perbezaan kesediaan guru mengamalkan Pengajaran Abad Ke-21 berdasarkan jantina dan bidang mata pelajaran. Kajian ini melibatkan 70 orang guru yang mengajar di sekolah ini. Sebanyak 4 bidang mata pelajaran yang terlibat dalam kajian ini. Kajian ini menggunakan soal selidik berskala Likert lima mata sebagai instrumen kajian. Instrumen ini mengandungi 2 item berkaitan demografi dan 54 item berdasarkan literasi, kemahiran dan sikap. Kajian rintis yang melibatkan 10 orang guru dilaksanakan bagi menentukan kesahan dan kebolehpercayaan instrumen kajian. Data dianalisis dengan menggunakan perisian Statistical Packages of Social Sciences 16.0 untuk mendapatkan peratusan, min dan sisihan piawai bagi kesediaan guru mengamalkan Pengajaran Abad Ke-21. Ujian-t sampel tidak bersandar pula menunjukkan bahawa tidak terdapat perbezaan yang signifikan kesediaan guru berdasarkan jantina. Ujian ANOVA sehala pula menunjukkan tidak terdapat perbezaan yang signifikan kesedian guru berdasarkan bidang mata pelajaran

Optimization of low-methoxyl pectin extraction from durian rinds and its physicochemical characterization

The current study investigates the influence of acid-heating extraction conditions on durian rind pectin yield and properties. A central composite rotatable design was employed to study the effect of extraction temperature (75 – 95 ◦C), duration (30 – 270 min), and solid-to-liquid ratio (S:L) (1:20 – 1:60 g/mL) at 0.001M H2SO4 on durian rind pectin yield, esterification degree (DE), and purity (AUA). Based on the results, pectin yield and AUA were significantly affected by extraction temperature, time, and S:L. Among them, extraction temperature was the most significant variable positively affecting the pectin yield and purity. DE was not pronouncedly influenced by extraction temperature, time, and S:L. Under the optimal extraction condition (93.3 ◦C, S:L 1:50 g/mL, 185 min), the experimental yield (12.12%) and AUA (77.21%) of the extracted pectin were in close agreement with the predicted values. The optimized pectin had DE = 18.99% and molecular weight = 42.12 kDa. The FT-IR spectrum showed that DP is rich in polygalacturonic acid. DP powders were homogenous slab-like granules with smooth surfaces and had relatively good thermal properties. Thus, durian rind is a potential source of low methoxyl pectin, which could be a capable thickener for low-calorie foods and beverages

Exploring Motion Sequence of Virtual Characters: Experimenting Motion Capture Variables

The purpose of the research is to study the detail of motion of various subjects with differences in physical attributes. The research outlines how different physique produces different behavioural patterns based upon mass and proportion. This research focuses on 'walk motion' to identify the differences in each subject's physical attributes by sampling subjects of physical differences. This experiment employs Vicon8i((R)) Optical Motion Capture system (MOCAP) to study the detail of human motion by extracting the subjects' core motions for analysis with pre-defined actions. The research used the findings to establish the relationship between height and weight against motion frequencies in 3D space

Understanding the Technicalities of Photorealistic 3D Environments to Support Cinematography and Composition for Film and Animation

This paper reviews the integration of Computer Graphics principles in simulating photorealistic 3D environments integrating life action footage for film. To achieve adequate believability and create impact, the look of the 3D background requires digital enhancement to achieve a certain stage of realism. This will depend primarily on the material/shader and renderer utilised in the 3D application. Despite having the realistic look, the other aspect to consider for a perfect merge between 3D and life requires one to skillfully match perspective and lighting. Another aspect to consider is the cinematography and composition of the scene