Search results for: Meng Koon Lee

Authors: Meng Koon Lee, Mohammad Hosseini Fouladi, Satesh Narayana Namasivayam

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Research is focused on the response of soundboards of Classical guitars at frequencies up to 5 kHz as the soundboard is a major contributor to acoustic radiation at high frequencies when compared to the bridge and sound hole. A thin rectangular plate of variable thickness that is simply-supported on all sides is used as an analytical model of the research. This model is used to study the response of the guitar soundboard as the latter can be considered as a modified form of a rectangular plate. Homotopy Perturbation Method (HPM) is selected as a mathematical method to obtain an analytical solution of the 4th-order parabolic partial differential equation of motion of the rectangular plate of constant thickness viewed as a linear problem. This procedure is generalized to the nonlinear problem of the rectangular plate with variable thickness and an analytical solution can also be obtained. Sound power is used as a parameter to investigate the acoustic radiation of soundboards made from spruce using various bracing patterns. The sound power of soundboards made from Malaysian softwood such as damar minyak, sempilor or podo are investigated to determine the viability of replacing spruce as future materials for soundboards of Classical guitars.

Keywords: rectangular plates, analytical solution, homotopy perturbation, natural frequencies

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Authors: D. Hassell, D. De Focatiis

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This paper presents work on the application of wiki based coursework for a fourth-year engineering module delivered as part of both a MEng and MSc programme in Chemical Engineering. The module was taught with an equivalent structure simultaneously on two separate campuses, one in the United Kingdom (UK) and one in Malaysia, and the subsequent results were compared. Student feedback was sought via questionnaires, with 45 respondents from the UK and 49 from Malaysia. Results include discussion on; perceived difficulty; student enjoyment and experiences; differences between MEng and MSc students; differences between cohorts on different campuses. The response of students to the use of wiki-based coursework was found to vary based on their experiences and background, with UK students being generally more positive on its application than those in Malaysia.

Keywords: engineering education, student differences, student learning, web based coursework

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Authors: Amaraja Taur, Pankaj Doshi, Hak Koon Yeoh

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The dripping modes for a Newtonian liquid of viscosity µ emanating from an inclined nozzle at flow rate Q is investigated experimentally. As the liquid flow rate Q increases, starting with period-1 with satellite drops, the system transitions to period-1 dripping without satellite, then to limit cycle before showing chaotic responses. Phase diagrams shows the changes in the transitions between the different dripping modes for different nozzle inclination angle θ is constructed in the dimensionless (Q, µ) space.

Keywords: dripping, inclined nozzle, phase diagram, satellite

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Authors: Zhiyan Meng, Dan Liu, Jintao Meng

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Dependable encrypted traffic classification is crucial for improving cybersecurity and handling the growing amount of data. Large language models have shown that learning from large datasets can be effective, making pre-trained methods for encrypted traffic classification popular. However, attention-based pre-trained methods face two main issues: their large neural parameters are not suitable for low-computation environments like mobile devices and real-time applications, and they often overfit by getting stuck in local minima. To address these issues, we developed a lightweight transformer model, which reduces the computational parameters through lightweight vocabulary construction and Squeeze-and-Excitation Block. We use sharpness-aware optimization to avoid local minima during pre-training and capture temporal features with relative positional embeddings. Our approach keeps the model's classification accuracy high for downstream tasks. We conducted experiments on four datasets -USTC-TFC2016, VPN 2016, Tor 2016, and CICIOT 2022. Even with fewer than 18 million parameters, our method achieves classification results similar to methods with ten times as many parameters.

Keywords: sharpness-aware optimization, encrypted traffic classification, squeeze-and-excitation block, pretrained model

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Authors: Rita Gill Singh, Alex Chun Koon, Cindy Sing Bik Ngai, Joanna Wen Ying Ho, Mei Li Khong, Enoch Chan, Terrence Lau

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Although humour is viewed as a beneficial element in teaching, there has been little attempt to systematize humour in teaching, possibly because it is difficult to teach someone to be humorous. This study integrated planned humour pedagogical approach into teaching and learning activities and examined the effect of systematically planned humour on students’ engagement and learning in different courses. Specifically, appropriate types of humour (i.e. analogy, absurdity and wordplay) and incorporation methods and frequency were systematically integrated into the lessons of courses at some higher education institutions in Hong Kong. The results showed that the planned humour pedagogical approach increased student engagement, as well as enhanced learning and motivation while reducing students’ stress. The pedagogical implications of this study will be useful for researchers, practitioners, and educators.

Keywords: higher education, pedagogy, humour, student engagement, learning, motivation

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Authors: Meng-Jou Chien, Jheng-Cheng Chen, Chang-Hsiung Tsai

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Let maxζG(m) denote the maximum number of edges in a subgraph of graph G induced by m nodes. The n-dimensional augmented cube, denoted as AQn, a variation of the hypercube, possesses some properties superior to those of the hypercube. We study the cases when G is the augmented cube AQn.

Keywords: interconnection network, augmented cube, induced subgraph, bisection width

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Authors: Koon Weng Lau, Chee Dhang Chen, Abdul Aziz Azidah, Mohd Sofian-Azirun

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Recently, Sarawak state of Malaysia encounter an outbreak of dengue fever. Aedes albopictus has incriminated as one of the important vectors of dengue transmission. Without an effective vaccine, approaches to control or prevent dengue will be a focus on the vectors. The control of Aedes mosquitoes is still dependent on the use of chemical insecticides and insecticide resistance represents a threat to the effectiveness of vector control. This study was conducted to determine the resistance status of 11 active ingredients representing four major insecticide classes: DDT, dieldrin, malathion, fenitrothion, bendiocarb, propoxur, etofenprox, deltamethrin, lambda-cyhalothrin, cyfluthrin, and permethrin. Standard WHO test procedures were conducted to determine the insecticide susceptibility. Aedes albopictus collected from Kapit (resistance ratio, RR = 1.04–3.02), Kuching (RR = 1.17–4.61), and Sibu (RR = 1.06–3.59) exhibited low resistance toward all insecticides except dieldrin. This study reveled that dieldrin is still effective against Ae. albopictus, followed by fenitrothion, cyfluthrin, and deltamethrin. In conclusion, Ae. albopictus in Sarawak exhibited different resistance levels toward various insecticides and alternative solutions should be implemented to prevent further deterioration of the condition.

Keywords: Aedes albopictus, dengue, insecticide resistance, Malaysia

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Authors: Shanshan Guo, Xiaoying Zhu, Dominik Jańczewski, Koon Gee Neoh

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Surface charge and wettability are two prominent physical factors governing cell adhesion and have been extensively studied in the literature. However, a comparison between the two driving forces in terms of their independent and cooperative effects in affecting cell adhesion is rarely explored on a systematic and quantitative level. Herein, we formulate a protocol which allows two-dimensional and independent control over both surface charge and wettability. This protocol enables the unambiguous comparison of the effects of these two properties on cell adhesion. This strategy is implemented by controlling both the relative thickness of polyion layers in the layer-by-layer assembly and the polyion side chain chemical structures. The 2D property matrix spans surface isoelectric point ranging from 5 to 9 and water contact angle from 35º to 70º, with other interferential factors (e.g. roughness) eliminated. The interplay between these two surface variables influences 3T3 fibroblast cell adhesion. The results show that both surface charge and wettability have an effect on its adhesion. The combined effects of positive charge and hydrophilicity led to the highest cell adhesion whereas negative charge and hydrophobicity led to the lowest cell adhesion. Our design strategy can potentially form the basis for studying the distinct behaviors of electrostatic force or wettability driven interfacial phenomena and serving as a reference in future studies assessing cell adhesion to surfaces with known charge and wettability within the property range studied here.

Keywords: cell adhesion, layer-by-layer, surface charge, surface wettability

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Authors: Jie Yang, Jian-Min Meng

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A GPU-based floating object detection scheme is presented in this paper which is designed for floating mine detection tasks. This system uses contrast and motion information to eliminate as many false positives as possible while avoiding false negatives. The GPU computation platform is deployed to allow detecting objects in real-time. From the experimental results, it is shown that with certain configuration, the GPU-based scheme can speed up the computation up to one thousand times compared to the CPU-based scheme.

Keywords: object detection, GPU, motion estimation, parallel processing

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Authors: Chee Dhang Chen, Hiroyuki Takaoka, Koon Weng Lau, Poh Ruey Tan, Ai Chdon Chin, Van Lun Low, Abdul Aziz Azidah, Mohd Sofian-Azirun

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Susceptibility status of Simulium (Simulium) nobile (Diptera: Simuliidae) adults obtained from Pahang, Malaysia was evaluated against 11 adulticides representing four major insecticide classes: organochlorines (DDT, dieldrin), organophosphates (malathion, fenitrothion), carbamates (bendiocarb, propoxur) and pyrethroids (etofenprox, deltamethrin, lambdacyhalothrin, permethrin, cyfluthrin). The adult bioassay was conducted according to WHO standard protocol to determine the insecticide susceptibility. Mortality at 24 h post treatment was used as indicator for susceptibility status. The results revealed that S. nobile obtained was susceptible to propoxur, cyfluthrin and bendiocarb with 100% mortality. S. nobile was resistant or exhibited some tolerant against lambdacyhalothrin and deltamethrin with mortality ranged ≥ 90% but < 98%. S. nobile populations in Pahang exhibited different level of resistant against 11 adulticides with mortality ranged from 60.00 ± 10.00 to 100.00 ± 0.00. In conclusion, S. nobile populations in Pahang were susceptible to propoxur, cyfluthrin and bendiocarb. The susceptibility status of S. nobile in descending order was propoxur, cyfluthrin > bendicarb > deltamethrin > lambdacyhalothrin > permethrin > etofenprox > DDT > malathion > fenitrothion > dieldrin. Regular surveys should be conducted to monitor the susceptibility status of this insect vector in order to prevent further development of resistance.

Keywords: black fly, adult bioassay, insecticide resistance, Malaysia

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Authors: Kang Liu, Meng Liu, Meng-Long Wu, Da-Chang Yue, Hong-Yi Pan

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The soil setup is an important factor affecting pile bearing capacity; there are many factors that influence it, all of which are closely related to pile construction disturbances. During pile installation in soil, a significant amount of excess pore pressure is generated, creating disturbance zones around the pile. The dissipation rate of excess pore pressure is an important factor influencing the pile setup. The paper aims to examine how alterations in parameters within disturbance zones affect the dissipation of excess pore pressure. An axisymmetric FE model is used to simulate pile installation in clay, subsequently consolidation using Plaxis 3D. The influence of disturbed zone on setup is verified, by comparing the parametric studies in uniform field and non-uniform field. Three types of consolidation are employed: consolidation in three directions, vertical consolidation, horizontal consolidation. The results of the parametric study show that the permeability coefficient decreases, soil stiffness decreases, and reference pressure increases in the disturbance zone, resulting in an increase in the dissipation time of excess pore pressure and exhibiting a noticeable threshold phenomenon, which has been commonly overlooked in previous literature. The research in this paper suggests that significant thresholds occur when the coefficient of permeability decreases to half of the original site's value for three-directional and horizontal consolidation within the disturbed zone. Similarly, the threshold for vertical consolidation is observed when the coefficient of permeability decreases to one-fourth of the original site's value. Especially in pile setup research, consolidation is assumed to be horizontal; the study findings suggest that horizontal consolidation has experienced notable alterations as a result of the presence of disturbed zones. Furthermore, the selection of pile installation methods proves to be critical. A nonlinearity excess pore pressure formula is proposed based on cavity expansion theory, which includes the distribution of soil profile modulus with depth.

Keywords: pile setup, threshold value effect, installation effects, uniform field, non-uniform field

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Authors: Nai-Chia Chao, Meng-Chi Shih

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Under today’s fast technology and massive data era, the working method start to change. In this study, based under literature meaning of “Co-working” we had implemented the new “Co-working innovation model”. Research concluded that co-working innovation model shall not be limited in co-working space but use under different field when applying multiple art integration stragies. Research show co-working should not be limited in special field or group, should be use or adapt whenever different though or ideas where found, it should be use under different field and plans.

Keywords: arts integration, co-working, children's musical

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Authors: Siti Sabariah Buhari, Ruzita Abdul Talib, Poh Bee Koon

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This study aims to develop and evaluate an intervention to improve eating habits, active lifestyle and weight status of overweight and obese children in Negeri Sembilan. The H.E.B.A.T! Program involved children, parents, and school and focused on behaviour and environment modification to achieve its goal. The intervention consists of H.E.B.A.T! Camp, parent’s workshop and school-based activities. A total of 21 children from intervention school and 22 children from control school who had BMI for age Z-score ≥ +1SD participated in the study. Mean age of subjects was 10.8 ± 0.3 years old. Four phases were included in the development of the intervention. Evaluation of intervention was conducted through process, impact and outcome evaluation. Process evaluation found that intervention program was implemented successfully with minimal modification and without having any technical problems. Impact and outcome evaluation was assessed based on dietary intake, average step counts, BMI for age z-score, body fat percentage and waist circumference at pre-intervention (T0), post-intervention 1 (T1) and post-intervention 2 (T2). There was significant reduction in energy (14.8%) and fat (21.9%) intakes (at p < 0.05) at post-intervention 1 (T1) in intervention group. By controlling for sex as covariate, there was significant intervention effect for average step counts, BMI for age z-score and waist circumference (p < 0.05). In conclusion, the intervention made an impact on positive behavioural intentions and improves weight status of the children. It is expected that the HEBAT! Program could be adopted and implemented by the government and private sector as well as policy-makers in formulating childhood obesity intervention.

Keywords: childhood obesity, diet, obesity intervention, physical activity

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Authors: Jiongbin Liu, William Yeoh, Shang Gao, Xiaoliang Meng, Yuhan Zhu

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The metaverse concept has sparked significant interest in both academic and industrial spheres. As educational institutions increasingly adopt this technology, understanding its implementation becomes crucial. In response, we conducted a comprehensive case study at a large university, systematically analyzing the nine stages of metaverse development initiatives. Our study unveiled critical insights into the planning, assessment, and execution processes, offering invaluable guidance for stakeholders. The findings highlight both the opportunities for enhanced learning experiences and the challenges related to technological integration and social interaction in higher education.

Keywords: metaverse, metaverse development framework, higher education, case study

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Authors: Tamas Jancso, Andrea Podor, Eva Nagyne Hajnal, Peter Udvardy, Gabor Nagy, Attila Varga, Meng Qingyan

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The paper deals with the conditions and circumstances of integration of remotely sensed data for rural environmental monitoring purposes. The main task is to make decisions during the integration process when we have data sources with different resolution, location, spectral channels, and dimension. In order to have exact knowledge about the integration and data fusion possibilities, it is necessary to know the properties (metadata) that characterize the data. The paper explains the joining of these data sources using their attribute data through a sample project. The resulted product will be used for rural environmental analysis.

Keywords: remote sensing, GIS, metadata, integration, environmental analysis

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Authors: Liyana Zahid, Mohd Fareq Abd Malek, Ee Meng Cheng, Wei Wen Liu, Yeng Seng Lee, Muhammad Nadeem Iqbal, Fwen Hoon Wee

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One of the parameters that affect the performance of microwave absorbers is the shape of the absorbers. This paper shows the performance (reflection loss) of truncated pyramidal and truncated wedge microwave absorbers in the range frequency between 8.2 to 12.4 GHz (X-Band) in simulation. The material used is sugarcane bagasse (SCB) which is one of the new materials that used to fabricate the microwave absorber. The complex permittivity was measured using Agilent dielectric probe technique. The designs were simulated using CST Microwave Studio Software. The reflection losses between these two shapes were compared.

Keywords: microwave absorber, reflection loss, sugarcane bagasse (SCB), X-Band

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Authors: Liu Ziyu, Gao Yongfeng, Li Muhua, Zhao Jiahao, Meng Song

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The effect of thermal shock on the operation of micro electromechanical systems (MEMS) were examined. All MEMS device were tested before and after three different conditions of thermal shock (from -55℃ to 85℃, from -65℃ to 125℃, from -65℃ to 200℃). The micro lens showed no changes after thermal shock, which shows that the design of the micro lens can be well adapted to the application environment in the space. The design of the micro mirror can be well adapted to the space application environment. The micro-magnetometer, RF MEMS switch and the micro accelerometer exhibited degradation and parameter drift after thermal shock, potential mechanical was proposed.

Keywords: MEMS, thermal shock test, reliability, space environment

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Authors: Chien-Ju Chen, Chia-Jui Yu, Jyun-Hao Liao, Chia-Ching Wu, Meng-Chyi Wu

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A 64 × 64 GaN-based micro-light-emitting diode array (μLEDA) with 20 μm in pixel size and 40 μm in pitch by flip-chip bonding (FCB) is demonstrated in this study. Besides, an underfilling (UF) technology is applied to the process for improving the uniformity of device. With those configurations, good characteristics are presented, operation voltage and series resistance of a pixel in the 450 nm flip chip μLEDA are 2.89 V and 1077Ω (4.3 mΩ-cm²) at 25 A/cm², respectively. The μLEDA can sustain higher current density compared to conventional LED, and the power of the device is 9.5 μW at 100 μA and 0.42 mW at 20 mA.

Keywords: GaN, micro-light-emitting diode array(μLEDA), flip-chip bonding, underfilling

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Authors: Soheila Raeisi, Meng Lingjie

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The interaction of customers with businesses is a process that is critical to the running of those businesses. Different levels of customer engagement and service innovation exist when pursuing value co-creation endeavors. The important thing in this whole process is for business managers know the benefits that can be realized when these activities are pursued effectively. The purpose of this paper is to first identify the importance of value co-creation when pursued via customer engagement and service innovation. Secondly, it will also identify the conditions under which value co-destruction can occur on the same. The background of the topic will be reviewed followed by the literature review with a special focus on the definition of these terms and the research design to be used. The research found that it is beneficial to have a strong relationship between stakeholders and the business in order to have strong customer engagement and service innovation.

Keywords: customer engagement, service innovation, value co-creation, value co-destruction

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Authors: Huai-Feng Wang, Meng-Lin Lou, Ru-Lin Zhang

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One good analysis method in seismic response analysis is direct time integration, which widely adopts Rayleigh damping. An approach is presented for selection of Rayleigh damping coefficients to be used in seismic analyses to produce a response that is consistent with Modal damping response. In the presented approach, the expression of the error of peak response, acquired through complete quadratic combination method, and Rayleigh damping coefficients was set up and then the coefficients were produced by minimizing the error. Two finite element modes of soil layers, excited by 28 seismic waves, were used to demonstrate the feasibility and validity.

Keywords: Rayleigh damping, modal damping, damping coefficients, seismic response analysis

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Authors: Meng-Yu Tsai, Jui-hun Chang, Wen-Feng Hung, Jing-Dong Chou

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The objective of this paper was to use gravitrap to survey the mosquito density in Kaohsiung. Gravitrap is one of the tools for surveillance the mosquito density. Gravitrap not only monitor the mosquito density but also decrease the mosquito density. Kaohsiung Environment Protection Bureau (KEPB) used gravitrap to monitor the mosquito density in 2016. KEPB put gravitrap in five districts which had the more confirmed dengue cases in 2015. The results indicated that (1)the highest positive rate (PR) of gravitrap was in Gushan district, the PR of gravitrap in Gushan district was 19.25%. (2) the lowest PR of gravitrap was in Sanmin district, the PR of gravitrap in Sanmin district was 8.55%. (3) compared these two districts, the most important factor to influence of PR of gravitrap was the knowledge of dengue prevention. Therefore, the PR of gravitrap was one of the references for making dengue prevention policy.

Keywords: continuous assessment, course integration, curricular reform, student feedback

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Authors: Meng-Hui Chen, Chen-Yu Kao, Chia-Yu Hsu, Pei-Chann Chang

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The main idea in this paper is using sequential pattern mining to find the information which is helpful for finding high performance solutions. By combining this information, it is defined as blocks. Using the blocks to generate artificial chromosomes (ACs) could improve the structure of solutions. Estimation of Distribution Algorithms (EDAs) is adapted to solve the combinatorial problems. Nevertheless many of these approaches are advantageous for this application, but only some of them are used to enhance the efficiency of application. Generating ACs uses patterns and EDAs could increase the diversity. According to the experimental result, the algorithm which we proposed has a better performance to solve the permutation flow-shop problems.

Keywords: combinatorial problems, sequential pattern mining, estimationof distribution algorithms, artificial chromosomes

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Authors: Houssam A. Toutanji, Meng Han

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This study focuses on the development of a fracture mechanics based-model that predicts the debonding behavior of FRP strengthened RC beams. In this study, a database includes 351 concrete prisms bonded with FRP plates tested in single and double shear were prepared. The existing fracture-mechanics-based models are applied to this database. Unfortunately the properties of adhesive layer, especially a soft adhesive layer, used on the specimens in the existing studies were not always able to found. Thus, the new model’s proposal was based on fifteen newly conducted pullout tests and twenty four data selected from two independent existing studies with the application of a soft adhesive layers and the availability of adhesive properties.

Keywords: carbon fiber composite materials, interface response, fracture characteristics, maximum shear stress, ultimate transferable load

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Authors: Lim Teck Beng, Thiha Kyaw, Poh Boon Kiat, Lee Ngai Meng

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This work presents discussion on the possibility of merging two emerging technologies in microwave; wireless power transfer (WPT) and RF energy harvesting. The current state of art of the two technologies is discussed and the strength and weakness of the two technologies is also presented. The equivalent circuit of wireless power transfer is modeled and explained as how the range and efficiency can be further increased by controlling certain parameters in the receiver. The different techniques of harvesting the RF energy from the ambient are also extensive study. Last but not least, we demonstrate that a low power wireless sensor network (WSN) can be power up by RF energy harvesting. The WSN is designed to transmit every 3 minutes of information containing the temperature of the environment and also the voltage of the node. One thing worth mention is both the sensors that are used for measurement are also powering up by the RF energy harvesting system.

Keywords: energy harvesting, wireless power transfer, wireless sensor network and magnetic coupled resonator

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Authors: Chunxiao Wu, Dongyun Jiang, Tao Jiang, Luxia Xu, Qian Xu, Meng Zhao, Qin Zhu, Zhigang Guo, Jinlan Pan, Suning Chen

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The stability and evolution of human genetics depends on chromosomes (and chromosome-chromosome interactions). We wish to understand the spatial location of chromosomes in dividing cells in order to understand the relationship between chromosome-chromosome interactions and to further investigate the role of chromosomes and their impact on cell biological behavior. In this study, we explored the relative spatial positional relationships of chromosomes [t (9;22) and t (15;17)] in B-ALL cells by using the three-dimensions DNA in situ fluorescent hybridization (3D-FISH) method. The results showed that chromosomes [t (9;22) and t (15;17)] showed relatively stable spatial relationships. The relative stability of the spatial location of chromosomes in dividing cells may be relevant to disease.

Keywords: chromosome, human genetics, chromosome territory, 3D-FISH

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Authors: Rina Yadav, Meng-Ting Tsai

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In the present scenario, sustainable buildings are in high demand. The essential decision for building sustainability is made during the design and preconstruction stages. Main objective of this study is reduction of unfavorable environmental impacts, which is a major cause of global warming. Based on this problem, to diminish the environmental hazards, present research study is applied to provide a guideline to designer that will be useful for material selection stage of designing. This can be achieved by using local available materials such as wood, mud, bamboos instead of cement, steel, concrete by reducing carbon dioxide emission. Energy simulation will be analyzed by software to get the comparable result. It will be encouraging and motivational for designer while using ecofriendly material to achieve points in Leadership in energy and environmental design (LEED) in green rating system.

Keywords: sustainability design, lead rating, LEED, building performance analyses

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Authors: Jyun-Hao Liao, Chien-Ju Chen, Chia-Jui Yu, Meng Chyi Wu, Chia-Ching Wu

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In this letter, we reported the fabrication of InGaAs micro-photodiode sensor array with the rapid thermal diffusion (RTD) technique. The spin-on dopant source Zn was used to form the p-type region in InP layer. Through the RTD technique, the InP/InGaAs heterostructure was formed. We improved our fabrication on the p-i-n photodiode to micro size which pixel is 7.8um, and the pitch is 12.8um. The proper SiNx was deposited to form the passivation layer. The leakage current of single pixel decrease to 3.3pA at -5V, and 35fA at -10mV. The leakage current densities of each voltage are 21uA/cm² at -5V and 0.223uA/cm² at -10mV. As we focus on the wavelength from 0.9um to 1.7um, the optimized Si/Al₂O₃ bilayers are deposited to form the AR-coating.

Keywords: InGaAs, micro sensor array, p-i-n photodiode, rapid thermal diffusion, Zn diffusion

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Authors: Shahnaz Mansouri, Xiao Dong Chen, Meng Wai Woo

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A new antisolvent vapour precipitation approach was used to make ultrafine submicron probiotic encapsulates. The approach uses ethanol vapour to precipitate submicron encapsulates within relatively large droplets. Surprisingly, the probiotics (Lactobacillus delbrueckii ssp. bulgaricus, Streptococcus thermophilus) showed relatively high survival even under destructive ethanolic conditions within the droplet. This unusual behaviour was deduced to be caused by the denaturation and aggregation of the milk protein forming an ethanolic protective matrix for the probiotics. Skim milk droplets which is rich in casein and contains naturally occurring minerals provided higher ethanolic protection when compared whey protein isolate and lactose droplets.

Keywords: whey, skim milk, probiotic, antisolvent, precipitation, encapsulation, denaturation, aggregation

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Authors: Jim S. Meng, Mammo H. Yewondwossen

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As a part of routine oesophageal HDR brachytherapy procedure, treatment planning takes about 45 minutes while patients are under light sedation. Some patients may suffer gagging and/or spasms, and the treatment may need to be aborted. A pre-prepared plan generated before the patient’s sedation may reduce the brachytherapy procedure time by forty minutes. This paper reports the rationality and evidence of pre-prepared treatment plans. A retrospective study of 28 patients confirm that all of the pre-prepared plans would be acceptable. The rationality of pre-prepared HDR brachytherapy plans is further confirmed by a systemic study with a wide range of applicator curvature and treatment volume. Detailed comparison between CT based treatment plans and pre-prepared plans are discussed. This argument holds also for endobronchial HDR brachytherapy. With the above evidence, pre-prepared plans have been used for all oesophagus and bronchus HDR brachytherapy cases in our clinic.

Keywords: HDR brachytherapy, treatment planning, oesophageal carcinoma, pre-planning

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Authors: Zhi-Jun Lu, Qi Lu, Meng Wu, Qian Xiang, Jun Gu

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The analysis of perforated steel members is a 3D problem in nature, therefore the traditional analytical expressions for the ultimate load of thin-walled steel sections cannot be used for the perforated steel member design. In this study, finite element method (FEM) and artificial neural network (ANN) were used to simulate the process of stub column tests based on specific codes. Results show that compared with those of the FEM model, the ultimate load predictions obtained from ANN technique were much closer to those obtained from the physical experiments. The ANN model for the solving the hard problem of complex steel perforated sections is very promising.

Keywords: artificial neural network (ANN), finite element method (FEM), perforated sections, thin-walled Steel, ultimate load

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