bluuebunny/crossref_metadata_2025 huggingface dataset:
Parasite‐mediated selection in a natural metapopulation of Daphnia magna
Authors: Cabalzar Andrea P. , Fields Peter D. , Kato Yasuhiko , Watanabe Hajime , Ebert Dieter
Published: October 2019

Parasite‐mediated selection varying across time and space in metapopulations is expected to result in host local adaptation and the maintenance of genetic diversity in disease‐related traits. However, nonadaptive processes like migration and extinction‐(re)colonization dynamics might interfere with adaptive evolution. Understanding how adaptive and nonadaptive processes interact to shape genetic variability in life‐history and disease‐related traits can provide important insights into their evolution in subdivided populations. Here we investigate signatures of spatially fluctuating, parasite‐mediated selection in a natural metapopulation of Daphnia magna. Host genotypes from infected and uninfected populations were genotyped at microsatellite markers, and phenotyped for life‐history and disease traits in common garden experiments. Combining phenotypic and genotypic data a QST–FST‐like analysis was conducted to test for signatures of parasite mediated selection. We observed high variation within and among populations for phenotypic traits, but neither an indication of host local adaptation nor a cost of resistance. Infected populations have a higher gene diversity (Hs) than uninfected populations and Hs is strongly positively correlated with fitness. These results suggest a strong parasite effect on reducing population level inbreeding. We discuss how stochastic processes related to frequent extinction‐(re)colonization dynamics as well as host and parasite migration impede the evolution of resistance in the infected populations. We suggest that the genetic and phenotypic patterns of variation are a product of dynamic changes in the host gene pool caused by the interaction of colonization bottlenecks, inbreeding, immigration, hybrid vigor, rare host genotype advantage and parasitism. Our study highlights the effect of the parasite in ameliorating the negative fitness consequences caused by the high drift load in this metapopulation.
Impact of pharmacologic inhibition of tooth movement on periodontal and tooth root tissues during orthodontic force application
Authors: Baxter Sarah J. , Sydorak Inna , Ma Peter X. , Hatch Nan E.
Published: October 2019

Objective

The goal of this study was to investigate potential negative sequelae of orthodontic force application ±delivery of an osteoclast inhibitor, recombinant osteoprotegerin protein (OPG‐Fc), on periodontal tissues.

Setting and Sample Population

Sprague Dawley rats from a commercial supplier were investigated in a laboratory setting.

Materials and Methods

Rats were randomly divided into four groups (n = 7 each): one group with no orthodontic appliances and injected once prior to the experimental period with empty polymer microspheres, one group with orthodontic appliances and injected once with empty microspheres, one group with orthodontic appliances and injected once with polymer microspheres containing 1 mg/kg of OPG‐Fc, and one group with orthodontic appliances and injected with non‐encapsulated 5 mg/kg of OPG‐Fc every 3 days during the experimental period. The animals were euthanized after 28 days of tooth movement for histomorphometric analyses.

Results

Root resorption, PDL area and widths were similar in animals without appliances and animals with appliances plus high‐dose OPG‐Fc. PDL blood vessels were compressed and decreased in number in all animals that received orthodontic appliances, regardless of OPG‐Fc. Hyalinization was significantly increased only in animals with orthodontic appliances plus multiple injections of 5 mg/kg non‐encapsulated OPG‐Fc when compared to animals without appliances.

Conclusions

Results of this study indicate that while pharmacological modulation of tooth movement through osteoclast inhibition is feasible when delivered in a locally controlled low‐dose manner, high‐dose levels that completely prevent tooth movement through bone may decrease local blood flow and increase the incidence of hyalinization.
Tree diversity is key for promoting the diversity and abundance of forest‐associated taxa in Europe
Authors: Ampoorter Evy , Barbaro Luc , Jactel Hervé , Baeten Lander , Boberg Johanna , Carnol Monique , Castagneyrol Bastien , Charbonnier Yohan , Dawud Seid Muhie , Deconchat Marc , Smedt Pallieter De , Wandeler Hans De , Guyot Virginie , Hättenschwiler Stephan , Joly François‐Xavier , Koricheva Julia , Milligan Harriet , Muys Bart , Nguyen Diem , Ratcliffe Sophia , Raulund‐Rasmussen Karsten , Scherer‐Lorenzen Michael , van der Plas Fons , Keer J. Van , Verheyen Kris , Vesterdal Lars , Allan Eric
Published: October 2019

Plant diversity is an important driver of diversity at other trophic levels, suggesting that cascading extinctions could reduce overall biodiversity. Most evidence for positive effects of plant diversity comes from grasslands. Despite the fact that forests are hotspots of biodiversity, the importance of tree diversity, in particular its relative importance compared to other management related factors, in affecting forest‐associated taxa is not well known. To address this, we used data from 183 plots, located in different forest types, from Mediterranean to Boreal, and established along a climatic gradient across six European countries (FunDivEUROPE project). We tested the influence of tree diversity, tree functional composition (i.e. functional trait values), forest structure, climate and soil on the diversity and abundance/activity of nine taxa (bats, birds, spiders, microorganisms, earthworms, ungulates, foliar fungal pathogens, defoliating insects and understorey plants) and on their overall diversity and abundance/activity (multidiversity, multiabundance/activity). Tree diversity was a key driver of taxon‐level and overall forest‐associated biodiversity, along with tree functional composition, forest structure, climate and soil. Both tree species richness and functional diversity (variation in functional trait values) were important. The effects of tree diversity on the abundance/activity of forest‐associated taxa were less consistent. Nonetheless, spiders, ungulates and foliar fungal pathogens were all more abundant/active in diverse forests. Tree functional composition and structure were also important drivers of abundance/activity: conifer stands had lower overall multidiversity (although the effect was driven by defoliating insects), while stands with potentially tall trees had lower overall multiabundance/activity. We found more synergies than tradeoffs between diversity and abundance/activity of different taxa, suggesting that forest management can promote high diversity across taxa. Our results clearly show the high value of mixed forest stands for multiple forest‐associated taxa and indicate that multiple dimensions of tree diversity (taxonomic and functional) are important.
Through the taste buds of a large herbivore: foodscape modeling contributes to an understanding of forage selection processes
Authors: Duparc Antoine , Garel Mathieu , Marchand Pascal , Dubray Dominique , Maillard Daniel , Loison Anne
Published: October 2019

How large herbivores track resource quantity and quality through time has formed the core of an abundance of literature on migratory populations in recent decades. Yet, relating foraging processes and habitat selection patterns in resident populations, where spatial heterogeneity of food resources is fine‐grained and/or where the portion of edible plants (i.e. the foodscape) is low, is challenging. We addressed this issue in a mountain population of chamois Rupicapra rupicapra, an intermediate feeder, whose individuals do not migrate. We relied on a rare combination of data on habitat use of 50 GPS‐collared females and data on the quantity (biomass) and quality (phenology) of edible resources in their landscape, derived from field sampling of vegetation, remote sensing and diet (DNA barcoding). The foodscape of the chamois was composed of a low proportion of the available biomass (<18%), including relatively high‐quality plants, with low spatial covariation between plant phenology and biomass. Chamois avoided areas with a low edible biomass (where the intake rate may be too low) and focused on areas with plants at approximately the flowering stage, whatever the average plant phenological stage available. Due to this constant preference for flowering plants, home range selection ratios therefore shifted during the summer from a selection of more advanced plants in June to their avoidance in August. When the phenology scores of all plants available, rather than edible plants only, were considered, areas with relatively more advanced plants were selected all summer long. This exemplifies that, when traits from edible plants are different from those of all plants available, it is crucial to consider the actual foodscape to decipher forage and habitat selection processes. By integrating species‐specific dimensions of resources in habitat selection studies, we believe understanding of the foraging processes will be improved.
Unskilled immigration, technical progress, and wages—Role of the household sector
Authors: Marjit Sugata , Pant Manoj , Huria Sugandha
Published: October 2019

This paper revisits the relationship between unskilled immigration and skilled wage in the context of the BREXIT episode. Our simple general equilibrium model introduces a household sector, the inclusion of which shows that both return to capital and effective skilled wage may increase with a greater inflow of immigrants. This is a novel outcome in the theory of trade and factor flows. In addition, though technical progress in a skill‐intensive sector raises wage inequality, it no longer displaces traditional jobs. Here, the usual negative impact of unskilled immigration on the traditional sector is mitigated by increased returns to the unskilled workers.
Using ichnological relationships to interpret heterolithic fabrics in fluvio‐tidal settings
Authors: Melnyk Scott , Gingras Murray K.
Published: October 2019

In fluvio‐tidal settings, the sediment is dominantly derived from the river systems. However, the importance of landward tidal transport of sediment in tidally influenced sedimentary environments is difficult to assess, particularly in the rock record. This problem is addressed using two intervals within the Lower Cretaceous McMurray Formation, each representing a distinct inclined heterolithic stratification motif. The ichnological variation between the heterolithic intervals is analyzed to determine which lithosomes are associated with brackish‐water (tidally influenced) colonization windows. From this, the relative fluvial influence responsible for the deposition of the fine and coarse members can be determined. Both of the inclined heterolithic stratification fabrics studied record the deposition of fluvio‐tidal point bars wherein the heterolithic bedding represents variations in river discharge. The first fabric comprises inclined heterolithic stratification in which bioturbation only occurs in mudstone beds. This fabric indicates that deposition occurred in more proximal positions within a fluvio‐tidal system (i.e. the outermost inner to middle estuary or distributary channels). In this example sand deposition is interpreted to represent high‐energy, freshwater dune migration within a fluvial‐dominated setting, whereas mud beds reflect brackish‐water suspension deposition during times of low river discharge. The second fabric, which is interpreted to have developed in more distal depositional positions (i.e. the middle estuary or seaward of the turbidity maximum in deltas), consists of inclined heterolithic stratification with laminated mudstone and bioturbated sandstone. In these inclined heterolithic stratification successions the mudstone beds were deposited under the influence of freshwater and heightened sedimentation rates, whereas bioturbated sandstone was colonized under brackish‐water conditions and in the presence of tidally facilitated sediment transport. In both examples, the bioturbated lithosomes are related to colonization windows that indicate the predominance at that time of marine or tidally influenced processes over fluvial processes.
Hamstring muscle elasticity differs in specialized high‐performance athletes
Authors: Avrillon Simon , Lacourpaille Lilian , Hug François , Le Sant Guillaume , Frey Alain , Nordez Antoine , Guilhem Gaël
Published: October 2019

The effect of training on hamstring flexibility has been widely assessed through the measurement of the maximal range of motion or passive torque. However, these global measures do not provide direct information on the passive muscle mechanical properties of individual muscle. This characterization is crucial to better understand the effect of interventions as selective adaptations may occur among synergist muscles. Taking advantage of shear wave elastography, we aimed to determine whether elite sport athletes exhibit different passive shear modulus of hamstring heads compared to controls. Passive shear modulus was measured on semitendinosus (ST), semimembranosus (SM), and biceps femoris (BF) using shear wave elastography with the knee flexed at 60° and 90°, and 90° of hip flexion. A total of 97 elite athletes from various sports including running sprint, figure skating, fencing, field hockey, taekwondo, basketball, and soccer and 12 controls were evaluated. The shear modulus measured at 60° of knee flexion was lower in SM for figure skating (P < .001; d = 1.8), taekwondo (P < .001; d = 2.1), fencing (P = .024; d = 1.0), and soccer (P = .011; d = 0.9) compared to controls, while no difference was found for athletic sprinters, field hockey, and basketball players. Shear modulus of the BF and ST muscle was not significantly different between controls and elite athletes, regardless of the sport specialization (all P values = 1). We provide evidence that the shear modulus of the SM is altered in athletes involved in elite sport practice performed over large range of motion and/or including substantial stretching program in training content (taekwondo, figure skating, fencing, and soccer).
A Review on Thermal Comfort Assessment in Malaysian Industries
Authors: Ismail Ahmad Rasdan , S A Karagaratnan Shashi Kumar , Zulkifli Rozli , Md Deros Baba , Abdul Rahman Mohd Nizam
Published: October 2019

In this world of advanced technology, many global organizations are realizing that the importance of their worker’s comfort level towards their performance in order to be competitive. The studies in thermal comfort allow enhancing the understanding the importance of working environment among workers and occupants from various fields. This paper is focuses on reviews of the recent studies on thermal comfort assessments at the industries in Malaysia. The findings from other researchers’ thermal comfort assessments at worldwide also reviewed together. This review would help the researchers, academicians and practitioners to take a closer look on how environmental factors affect human performance in industries and help to enhance the awareness on human comfort among all Malaysians.
Barriers to Implement Lean Manufacturing in Malaysian Automotive Industry
Authors: Sahwan Mohd Azhar , Ab Rahman Mohd Nizam , Md Deros Baba
Published: October 2019

Implementing lean manufacturing in a developing country such as Malaysia is still considered to be a major challenge due to several barriers. It is essential for all managers to understand these barriers and try to minimize them and improve competition strength. The purpose of this study is to investigate the barriers of lean manufacturing in the automotive industry in Malaysia. A survey have been conducted and sent to 250 companies from automotive manufacturing plant and suppliers in Malaysia, giving a 20.8% response rate. The statistical package for the social science (SPSS) software was used to analyze the data from the surveys. The result shows that the lack of skilled is the highest obstacle implement lean and following by lack of awareness and company culture. Attempt was made at finding significance difference between small, medium and large companies on obstacle in lean implementation. The findings of this research provide invaluable information to all desire to implement lean manufacturing and to assist the development of an effective strategic plas as well as to design programs to overcome the lean manufacturing barriers. The findings culminate with conclusion together with some proposed future research directions.
Benchmarking Technique in Lean Manufacturing (5s) Practice
Authors: Mohd Deros Baba , Jun Tan , Abd Rahman Mohd Nizam
Published: October 2019

In todayâ€™s competitive market, low cost production and high quality product could assists manufacturers to win new and maintain their existing customers thus gain bigger market share. Manufacturing cost is one of the key dominant factors towards achieving business success. As such, manufacturing firms are struggling to produce product with lowest manufacturing cost while at the same time maintaining their product quality. Lean manufacturing practice could be applied to lower the manufacturing cost and benchmarking technique to ensure on the implementation effectiveness. A case study was conducted in a small and medium manufacturing firm located in China. One of the lean manufacturing tools, i.e. 5S system was implemented in the production line of the case study company. For future reference, the present situation was studied prior to the 5S system implementation. Later, the result of the study was benchmarked against before, after and the best in class manufacturer. A framework was developed to guide the user during implementing the 5S system. The benchmarking result shows significant improvement in productivity and lower manufacturing cost after implementing the 5S system. The implementation of 5S system had created more comfortable workspace to production workers, standard procedures and method to produce the product. Therefore, it can be concluded, the 5S system was able to help the production workers to implement the lean manufacturing and benchmarking technique more effectively to bring additional advantages in producing lower cost and high quality product, which eventually helps the company to gain better market share.
Effect of Dry and Wet Ball Milling Process on Critical Powder Loading and Mixture Properties of Fine WC-10Co-0.8VC Powder
Authors: Fayyaz Abdolali , Muhamad Norhamidi , Sulong Abu Bakar , Yunn Heng Shye , M. Amin Sri Yulis , Rajabi Javad
Published: October 2019

Micro powder injection molding (μPIM) has great potential for the production of micro cemented carbide parts that require high hardness and toughness. The main stages of the μPIM process include mixing the powder and organic binder, injecting, debinding, and sintering. High critical solid loading of submicron tungsten carbide (WC) powder is one of the requirements in the micro powder injection molding process, which is not obtained easily. This paper investigates the effects of ball milling on critical solid loading of submicron WC. Dry and wet ball milling processes were used to prepare a powder mixture with composition of WC-10Co-0.8VC (wt-%). Critical powder volume concentration (CPVC) was determined using the torque variation method, and the powder characteristics were assessed using scanning electron microscopy and energy dispersive X-ray spectroscopy. CPVC was at 42% and 50% for the dry and wet ball milling processes, respectively. Apparent and tap densities of the powder mixture were achieved at 2.4 g/cm3 and 2.96 g/cm3 after dry milling and at 2.54 g/cm3 and 3.39 g/cm3 after wet milling, respectively. Wet ball milling causes fine particles to de-agglomerate and improves the critical solid loading, which is advantageous for submicron cemented tungsten carbide injection molding. The homogeneity of the powder mixture can improve under longer time of wet milling process and it can be expected that reduce microstructure defects in sintered components.
Solvent Debinding Process for ZK60 Magnesium Alloy Mim Compact
Authors: Harun Mohd Ruzi , Muhamad Norhamidi , Sulong Abu Bakar , Mohamad Nor Nor Hafiez , Jamaludin Khairur Rijal , Ibrahim Mohd Halimirwan
Published: October 2019

The influence of the leaching temperatures on the solvent debinding process of ZK60 magnesium alloy compact has been investigated. In this experiment, the soluble binder, palm stearin molecules were extracted out from the compact parts by immersing the compact parts in an n-heptanes solution. The solvent debinding rate was then investigated under the conditions of different leaching temperatures. The weight loss percentages of palm stearin were calculated and the pore structure evolution was analyzed by scanning electron micrograph. Results show that a complete diffusion of the palm stearin molecules out of the compact part best at 600C within 4 hours of extraction time.
Kerf Width Optimization in Wire-Cut Electrical Discharge Machine by using Taguchi Method
Authors: Ramli Rizauddin , Ahmad Roazam , Abd Ghani Jaharah
Published: October 2019

Today, in most of wire cut electrical discharge machine (WEDM), the suitable machining parameters are relied based on the data from machine manufacturer and the experience of operators. The situation became more difficult when involving numerous and diverse range of parameters and the lack of experience. Normally, the parameter tables given by the machine manufacturer is only for basic machining operation but not for optimum machining condition. The optimal machining parameters only can be achieved by determining significant parameters that are affecting the machining performance. In this paper, a Taguchi Method quality design and analysis of variance (ANOVA) is used to determine the optimal kerf width for material tool steel grade DF-2 for machining process with WEDM. The optimum machining parameter is obtained by using a analysis of signal-to-noise (S/N) ratio. After several experiments, it can be ascertained the significant parameter contributed to the kerf witdh are the open circuit voltage(47%), pulse duration(20%) and wire speed(15%). The average of kerf width from the three experiments was 0.255mm and from that, the error margin is only 1.53%, which satisfied our data .
Preparation and Characterization of Nanoporous Silica Aerogel Granules on The Basis of Water Glass Via Ambient Pressure Drying Method
Authors: Amirjan Ehsan , Mirzaee Omid , Soleimani Dorcheh Mohammad Reza , Dorcheh Ali Soleimani
Published: October 2019

A crack-free silica aerogel monolith is a nanostructured material with so many surprising properties such as high specific surface area, high porosity, low dielectric constant, low density and outstanding heat insulation properties that were fabricated from a cheap water glass derived silicic acid solution.In this research , the OH surfaces of the wet gel were modified using a HMDZ/n-hexane or TMCS/n-hexane mixture followed by solvent exchange from water to n-hexane. The obtained surface modified wet gel was dried at different temperature under ambient pressure.The properties of hydrophobic silica aerogels synthesized by this new route were investigated by scanning electron microscopy (SEM), differential temperature analysis (DTA) and Fourier-transform infrared spectroscopy (FT-IR).The results showed that 20 wt% HMDZ as surface modifier and 75 °C as drying temperature resulted an acceptable hydrophobic silica aerogel with the density of 0.15 gr/cm³ and specific surface area of about 520 m²/gr.
The Influence of Carbon Addition on the Physical and Mechanical Properties of WC-Co Sintered Powders
Authors: Mahaidin Ahmad Aswad , Selamat Mohd Asri , Abdul Manaf Samsiah , Jaafar Talib Ria
Published: October 2019

The mechanical properties of WC-Co are highly dependent on its cobalt content, density and grain size of the WC particles. Addition of free carbon during the consolidation of process is said to improve the densification process and inhibit grain growth. However, there are still plenty of works needs to be done regarding this matter to support the fact. Therefore, this study is to evaluate the effect of carbon addition on the physical and mechanical properties of WC-Co-C sintered powders. The WC-Co-C sample is fabricated using powder metallurgy technique, in which the powders were uniaxially pressed at 625 MPa and cold-isostatic pressed at 200 MPa. Then, the sample is sintered in nitrogen-based atmosphere at temperature range of 1350-1450C. The physical and mechanical properties of the WC-Co sintered powders were analysed. It is found that WC-Co-C has a relatively higher density and hardness but exhibit lower transverse rupture strength compared to WC-Co.
Detection of Sizes and Locations Air Voids in Reinforced Concrete Slab using Ground Penetrating Radar and Impact-Echo Methods
Authors: Abdul Razak Nurhayati , Senin Syahrul Fithry , Hamid Roszilah
Published: October 2019

The presence of inevitable air void defects in reinforced concrete components due to poor quality control during construction can further aggravate the moisture and chloride penetration in concrete to accelerate the corrosion process of the reinforcing steel. Non-destructive test  (NDT) methods, Ground Penetrating Radar (GPR) and Impact-Echo (IE), are utilised tp detect the void defects. This study is to compare the accuracy and limitations of both methods in detecting the sizes and depths of the air voids. The sample is a 600 × 400 ×200 mm3 reinforced grade 40 concrete slab with embedded air voids in the sample. The air-voids are introduced in the concrete slab by positioning air-void plastic balls with diameters of 67, 45, 27, 20 and 3 mm each at the depths of 70, 80, 100, 80 and 80 mm, respectively, from the top surface of the slab. Results show that GPR can detect the air voids with sizes larger than 20 mm in diameter with error ranging from -8.9 to 30% from their actual diameters. The IE method is only able to detect the air voids depths and not the voids’ sizes. It is also observed that the void depth estimation acquired by GPR is more accurate only for large size void (67 mm), but for sizes less than that, IE is more accurate in determining their locations. Both methos should be considered for NDT application in detecting voids depending on which parameter accuracy is inticipated.
MULTIMEIDA DESIGN PRINCIPLES IN DEVELOPING MULTIMEDIA LEARNING APPLICATION (MMLA) TO INCREASE CHILDREN AWARENESS OF CHILD SEXUAL ABUSE
Authors: Othman Azliza , Wan Yahaya Wan Ahmad Jaafar
Published: October 2019

This paper is focusing on multimedia design principles as a design strategy in designing and developing a multimedia learning application with purpose to increase children’s awareness of potential sexual abuse situations. Currently, children’s knowledge and awareness about danger and self-protection is still lacking and they are not totally aware of prohibited adult’s touches over their body. In such situation, they need to be educated and made aware of. In such situation, with the advantages of current multimedia technologies, learning can be supported by effective multimedia application. Accordingly, this study develops a learning application by adapting an instructional design model for design and development by Alessi and Trollip. Then, alpha and beta testing has been conducted with the help of an expert. It was found that the advantages of multimedia technology can facilitate children in better understanding of child sexual abuse and improve their awareness of the issues.
EFFECTS OF INDEX LEARNING STYLES (ILS) ON LEARNERS PREFERENCES STYLES TOWARDS LEARNING AUTISM BEHAVIORAL SYMPTOMS
Authors: Dolah Jasni , Bidin Mohamad Omar
Published: October 2019

In Malaysia, the issue of Autism is silently increasing and it needs to be considered seriously by a society. Azizan (2008) stated that based on a research conducted in Perak; one in every 625 children was autistic. Even though the finding does not represent the actual number of children being affected in Malaysia, the actual number might be higher than that in the real situation. The lack of research particularly on how society should be taught on this disability makes the situation become worse. Nobody knows what causes autism; no proper guide has been distributed and no information on autism was shared at school level. Autism needs special attention from society since the cause of this disability was unknown. More support in terms of research and guidance is needed. Most of the past research and study only focused on autistic children and their parents. Those findings mostly too scientific to be understood by the societies and the results does not often to be published. So in order to increase the knowledge and awareness of learners', the learners preferences style need to be identify in the first place so that when designing the learning material, it can suits and match with their learning styles. In this case, the instrument of Index Learning Styles (ILS) which developed by Felder and Soloman (1994) has been utilized. This instrument consists of forty four (44) items that fall under four categories; Sensing-intuitive, Visual-verbal, Active-reflective and sequential-global. The finding shows that visual learners are dominant compared to text learners. The findings from this study help researcher to develop a suitable an Interactive Multimedia Learning Environment (IMLE) which based on visuals characters which can helps society in learning Autistic behavioral symptoms.
PROPOSING THE THIRD GENERATION OF AN ALIGNED ACTIVITY SYSTEM AS A THEORETICAL FRAMEWORK IN BLENDED LEARNING RESEARCH
Authors: Ali Mohd Fadzli , Joyes Gordon , Ellison Linda
Published: October 2019

Many international researchers across various disciplines have adopted the use of activity theory in interactive digital media research, namely blended learning research. Activity theory has been widely applied into various educational fields such as understanding language, learning mathematics, and developing systems of Computer-Supported Collaborative Learning (CSCL) features. Researchers should consider using the third generation of activity system to develop a theoretical framework for the study of blended learning as it could provide important insights into both online and classroom activities. This paper suggests the development of a theoretical framework for blended learning research by integrating the third generation of activity system (Engeström, 1999), the concept of sub-triangles within each activity system (Jenlink, 2001) and the concept of constructive alignment (Biggs, 1999).
ENJOYABLE GAME DESIGN: A STUDY OF MOTOR-IMPAIRED USER’S PERCEPTION
Authors: Mat Zain Nurul Hidayah , Jaafar Azizah , Abdul Razak Fariza Hanis
Published: October 2019

Nowadays, playing computer games is a popular form of entertainment, which is particularly appealing to university students. This is the case because computer games offer enjoyable experience. However, studies which examine the users’ perception on enjoyable game design are limited, specifically in relation to motor-impaired users. Analyses of such perceptions can support the designer in designing enjoyable games for special needs users. The present study explored motor-impaired users’ perception based on constructs in Flow Theory. Six constructs, namely clear goal, feedback, user control, challenge, immersion and adaptively were used. In total, 42 students from UiTM Malaysia participated in this study. The data were analyzed using standard descriptive statistical methods. The findings of the study showed motor-impaired users’ perception on enjoyable game design. Hopefully, the results of the study will emphasize the need for developing a rigorous game design which is enjoyable for motor-impaired users.
APPLYING GESTALT VARIABLES IN LEARNING PHOTOGRAPHY WITH VIRTUAL GAMES
Authors: Mohamad Fakri Siti Hajar , Yusoff Amri , Said Che Soh
Published: October 2019

Photography is one of the major disciplines for graphic students. This course is usually conducted during the early semesters of studies and students are usually exposed to a basic level. Only after years of training and in the field studies, students are able to acquire the correct skills and techniques in photography. Therefore, early photographs produced by college students display a lack of merit and are less superior in quality. Moreover, these pictures look empty and any sublime messages, intended for the audience, are conveyed in a vague and misleading fashion. This paper defines six variables of the gestalt theory for enhancing the students’ skills and performance in photography. Gestalt theory can be used and applied to develop artwork into being more interesting and vibrant. The conceptual model is introduced and aims for educators to use it as a guide for teaching photography in their courses; so that students can upgrade their skills and performance earlier and make use of game based learning as an interactive media for learning photography.
APPLICATION OF RISK REDUCTION STRATEGIES IN THE CHEMICAL PROCESS INDUSTRY
Authors: Hussin N.E. , Kidam K. , Jalani Jihan J. , Johari A. , Hashim H. , Hassim Mimi H.
Published: October 2019

Recent accident analyses show that the accident rates in the chemical process industry (CPI) were still not decreasing. In the paper, the issues and challenges of risk reduction strategies were discussed. A case study using accident cases, extracted from the U.S. Chemical Safety and Hazard Investigation Board (CSB) database was conducted. The results of the accident analysis were discussed and then compared to previous analysis of the Failure Knowledge Database (FKD, Japan). The CSB analysis shows that the industry had moved from procedural risk reduction strategies to inherently safer and add-on engineered strategies. After 10years improvement, the industry was approaching towards more balanced safety management to prevent occurrence and recurrence of accidents with the emphasis on both management and engineering risk reduction strategies.
A STUDY OF THE LOSS CHARACTERISTIC OF A HIGH PRESSURE ELECTROLYZER SYSTEM FOR HYDROGEN PRODUCTION
Authors: Salami Tijani Alhassan , Abdol Rahim A.H. , Badrol Hisam Mohd Khairulddin
Published: October 2019

The aim of this paper is to analyse loss characteristic of a high-pressure electrolyzer system for hydrogen production. Fundamental thermodynamics and electrochemical relations related to polymer electrolyte membrane (PEM) electrolyzer have been modelled in MATLAB. Simple proton exchange membrane water electrolysis is analysed on the basis of well-known Butler-Volmer kinetic for the electrodes and transport resistance in the polymer-electrolyte. The overpotential at the anode, cathode and overpotential due to ohmic resistance were analysed individually. A sensitivity analysis was carried out to study the effect of exchange current density on Faraday efficiency. At current density of 0.2A/cm2, a higher efficiency of 87.8 % was observed.
FLIGHT PERFORMANCE OF VARIOUS BLENDED WING-BODY SMALL UAV DESIGNS
Authors: Nasir Rizal E. M. , Mohamed Firdaus , Ramly Ramzyzan , Mamat Aman M. I. , Wisnoe Wirachman , Kuntjoro Wahyu
Published: October 2019

Currently there are four BWB designs that have been tested in the LST-1 wind tunnel at Flight Technology and Test Centre (FTTC), UiTM since 2005. The objective of this paper is to analyse their flight performance of these four BWB UAVs in terms of airspeed flight envelope, endurance, range and rate of climb as a function of the number of batteries and to determine the optimal number of batteries to be carried for 1-hour endurance mission and 3-hour endurance mission. The targeted cruising-loitering airspeed mission for all these BWBS are around 20 to 40 mph (8.9 m/s to 17.8 m/s) and they are to possess the lowest take off/landing speed and the highest maximum speed possible. This paper also seeks to find the best design of the four to explore its maximum potential in the near future where a prototype will be constructed. Unlike conventionally powered aircraft that uses fuel, which burns out thus reducing total weight of aircraft as it flies for long hours, these four BWB electric-powered vehicles carry batteries and the weight shall remain constant throughout the flight.
CHARACTERIZATION OF PERODUA MYVI K3-VE I4 ENGINE PERFORMANCE USING EXHAUST GAS RECIRCULATION (EGR)
Authors: Mat Muhammad M. Hanif , Hanafiah A. Qaiyum , Ihsan Mamat Aman Mohd
Published: October 2019

Internal combustion engines are the main power source for  automobile vehicles.  As current  emission regulations becomes more stringent, more fuel efficient and less polluting engines are becoming the focus of car manufacturers. This paper presents the study of improving the performance of K3-VE I4 internal combustion engine that is used in the Perodua Myvi for the Perodua Eco-Challenge 2013. The strategy was  to use an EGR system to reduce Brake Specific Fuel Consumption (BSFC) while maintaining or increasing the engine power. The effects of different location of EGR on the engine performance were tested on a chassis dynamometer. The sensitivity of the engine performance and gas emission were studied since EGR implementation plays a  major role in influencing NOx emission. The performance parameter such as engine power and BSFC were then analysed. The result shows that a significant increase of power can be achieved and a reduction of around 56% was obtained on the BSFC. While the best NOx reduction was around 93%. These improvements are obtained at low RPM that corresponds to Perodua Eco-Challenge’s objective.
SOBEL OPERATOR FOR EDGES DETECTION IN SURFACE TEXTURE ANALYSIS
Authors: Ismail Mohd Fauzi , Jaafar Talib Ria , Che Pin Nuraini , Zaini Nor Hidayawati
Published: October 2019

The classification of surface textures has been changed for the convenience of design, manufacture and metrology. Surface texture can be divided into two types which are engineered and structured surface. One examples of structured surface is dimple edge type of surface. This kind of surface usually has a deterministic structure, with high aspect ratio geometric features. Modern dimple golf ball is the example of structured surface application witches its functional requirement, was to reduce air drag through better hydrodynamic flow around the ball. From the analysis of dimpled surface, process variation can be enhanced and the uniformity of the surface features can be improved. Hence, the work presented in this paper is intended to improve the quality of segmentation method for the dimple edges type of surface and Sobel Operator algorithm is proposed to be used. In Sobel Operator algorithm, two kernels is applied which one kernel identifies the horizontal edges and the other kernel identifies the vertical edges. By passing these two kernels, gradient along x direction and gradient along the y direction can be computed at the different location and finally determined the edges of the surface. Sobel operator application shows that the location of the edges becomes clearer and topography segmentation based on features edges is possible.
MEDIATING IMPACT OF MANUFACTURING TECHNOLOGY, LEAN AND STRATEGIC FLEXIBILITY ON MANUFACTURING PERFORMANCE
Authors: Mohamed Ismail Risyawati , Che Razak Razli , Mad Lazim Halim
Published: October 2019

In respect of Malaysian lean manufacturer; there has been insufficient research on what are the winning formulae to overcome the mounting challenges from the business environment. In this study, three identified strategies i.e lean, manufacturing technology and strategic flexibility, that could positively improve manufacturing performances, are investigated in depth. The research approach used was quantitative with data analyzed using SmartPLS. Results from this study also emphasize several interesting quasi - paradoxical  relationships which implied that Malaysian lean manufacturers prefer a cautious approach towards manufacturing technology implementation, preferring to incorporate technology in a more stable business environment and view strategic flexibility as unfavorable toward performance improvement.  In conclusion, this study manages to produce a strong predictive strategy-performance model, which explains the mediation impact of manufacturing strategies on external environmental factors and manufacturing performance.
THE INFLUENCE OF IT INFRASTRUCTURE IN BUSINESS PROCESS REENGINEERING PROJECT PERFORMANCE IN ISLAMIC BANKING.
Authors: Md Sin Muhammad Aizat , Razalli Mohd. Rizal
Published: October 2019

The purpose of this study is to investigate the relationship between IT infrastructure and performance of Islamic banking branches in Kedah from the perspective of Maqasid al-Shari’ah. IT infrastructure is critical factor to Business Process Re-Engineering (BPR). Maqasid al-Shari’ah is defined in terms of educating individual, establishing justice and promoting public interest. The questionnaires were sent directly to banks’ branches and collected by hand. 59 questionnaires were returned; however, only 54 samples were used for further data analysis. The data were analyzed using the simple regression analysis. Collectively, the result showed that IT infrastructure significantly influences the overall performance of Islamic banking branches in Kedah from the perspective of Maqasid al-Shari’ah as well as in terms of educating individual, establishing justice and promoting the public interest. The outcomes of this study provide an important understanding to both managers and researchers about the relationship between IT infrastructure and bank performance from the perspective of Maqasid al-Shari’ah.
AHSS AUTO STAMPING CHALLENGES: RECTIFYING SPRINGBACK
Authors: Mohtar S. , Baluch N. , Abdullah C. S.
Published: October 2019

To improve crash worthiness and fuel economy, the automotive industry is, increasingly, using Advanced High Strength Steel (AHSS). The main reason to utilize AHSS is their better performance in crash energy management, which allows one to down gauge with AHSS. In addition, these engineered AHSS address the automotive industry’s need for steels with higher strength and enhanced formability. The improved capabilities the AHSS bring to the automotive industry do not bring new forming problems but certainly accentuate problems already existing with the application of any higher strength steel. These concerns include higher loads on presses and tools, greater energy requirements, and increased need for springback compensation and control. Springback problem, consistently, is one of the leading roadblocks hindering auto stamping productivity. This paper describes the origins and types of springback, characterizes what causes it, and elaborates ways to rectify it through, stabilization, compensation, and verification.
PRELIMINARY STUDY ON ANTECEDENTS OF SUSTAINABLE CONSTRUCTION AMONG CONTRACTING COMPANIES OPERATING IN MALAYSIA.
Authors: Bamgbade J. A. , Kamaruddeen, A.M. , Nawi M.N.M , Aziz Z.
Published: October 2019

There has been an increasing demand on the construction industry to incorporate sustainability practices and principles in their operations and construction products, considering the industry’s contribution to environmental degradation. It is therefore crucial for the construction industry to adopt sustainable construction, thereby reducing the negative impacts of construction activities on the environment. While there are several sustainable construction studies in Malaysia, a study that integrates innovativeness, culture, government support and sustainable construction in a single framework has not been given a considerable attention. The objectives of this study are to develop a framework that incorporates the antecedents of sustainable construction; and to assess the validity and reliability of the research instrument. Data were obtained from thirty respondents using a sixty-one item instrument. The data obtained were analyzed using SPSS software to assess the instrument’s reliability. The results of the Cronbach’s Alpha test reveal a strong internal reliability of the study’s constructs and the overall instrument. This paper complements the existing body of knowledge on sustainable construction.
COMPACT DUAL-BAND DIELECTRIC RESONATOR ANTENNA FOR 2.4/5.8 GHZ WLAN APPLICATIONS
Authors: Mataria A. , Kamarudin M. R. , Khalily M.
Published: October 2019

Design of a Dual-Band Dielectric Resonator Antenna (DRA) for the radio-frequency identification (RFID) and wireless local area network (WLAN) is presented. The necessity of a compact sized dual-band antenna is to allow the manufacturers to produce small size high-performance WLAN access points. The proposed antenna consists of printed T-Shaped monopole antenna and rectangular dielectric resonator to operate simultaneously at 2.4 and 5.8 GHz. The monopole antenna was printed on a standard 1.6 mm FR4 substrate material. Impedance bandwidth for -10 dB return loss in the 2.35 GHz and 5.86 GHz center frequency reaches 0.25 GHz (2.22 GHz to 2.47 GHz) and 0.28 GHz (5.72 GHz to 6 GHz), respectively. A good agreement is achieved between measured and simulated results.  This compact antenna fed by a 50 Ω microstrip line is a low-profile and easy to manufacture antenna.
COOPERATIVE RELAY PROTOTYPE DEVELOPMENT AND PERFORMANCE MEASUREMENT
Authors: Orikumhi Igbafe , Sabirin Muhammad Rushidi , Leow Chee Yen
Published: October 2019

To meet the demand for high data rate, the wireless cellular system technology has grown in a steady pace in recent years. However, due to multipath fading, shadowing effects and path loss, the wireless communication links are prone to errors. To improve the communication link, at the cell edge and shadowed environment, cooperative relaying scheme has been proposed. In cooperative relaying, an additional node is placed between the source and destination terminals, to provide redundant path for data transmission. However, existing literature on cooperative relaying only investigates the system performance through theoretical simulations. The real world performance remains unknown because of the lack of prototypes for field testing and measurement. This work focuses on the development of an amplify-and-forward (AF) cooperative relaying prototype. The prototype is developed using the LabVIEW system development platform and the implementations are carried out on Universal Software Radio Peripheral (USRP). The performance of the AF based cooperative relaying prototype is measured in terms of the bit error rate (BER) and compared with the direct communication link without relay. The measured results show that cooperative relay assisted communication achieves significant improvement in terms of signal reliability, coverage distance and power efficiency.
STEERABLE ARRAY ANTENNA USING A 2 × 2 BUTLER MATRIX FOR 5G APPLICATIONS
Authors: Orakwue Stella Ifeoma , Ngah Razali , A. Rahman Tharek , Sa’ad B. M. , Khalily Mohsen
Published: October 2019

This paper presents the design of a beam steerable array antenna based on branch line coupler (BLC) at 28 GHz frequency band for fifth generation (5G) wireless applications.  The array is designed using Rogers RT/duroid 5880 substrate material of 0.254 mm thickness and dielectric constant of 2.2. The designed antenna has six elements array and is fed by a BLC which serves as a beamformer to obtain the beam scanning ranging from -16 to +16 degrees. The maximum gain of 14.5 dBi and a wideband that cover from 25.2 GHz to 32 GHz was obtained by measurement. The proposed antenna is applicable to 28 GHz frequency band proposed for 5G wireless communications. All simulated and measured results are clearly presented.