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Following the tsunamis occurred in Japan (2011) and Indian Ocean (2004), investigating interaction between coastal structures and tsunamis became necessary. Although several attempts have been made to estimate the tsunami forces acting on the coastal structures, there still remain inconsistencies among the published design guidelines. This research includes an experimental study to investigate the interaction between a tsunami surge and a coastal structure. The tsunami surge was generated using a novel dam-break system, capable of generating higher tsunami surges than the previous simulations. The relations between surge velocity, surge depth, and surge-induced pressure on the structure were presented. In the surge-induced pressure–time histories, there were three identified force components, namely, run-up, impulsive and quasi-steady hydrodynamics. Furthermore, this research presents a comparison made between the experimental results and existing tsunami guidelines. The ratio of impulsive force to hydrodynamic force was found around 2.4 for each tsunami surge. The hydrodynamic forces were found to be higher with respect to those determined using the ‘Federal Emergency Management Agency’ FEMA P646 guidelines, whereas they were approximately in agreement with those obtained by FEMA 55. Moreover, the results showed that the ‘Structural Design Method of Building for Tsunami Resistance’ overestimates the impulsive force.

Thermal comfort is the human subject perceived satisfaction to the environmental condition. The human comfort level is affected by skin temperature. Currently to determine the human skin temperature by using human experiment in a controlled environment. However, the experiment is very rigorous and exhaustive. This study was conducted to predict human skin temperature under comfort level with using the finite element method and the bioheat equation. The bioheat equation is used to predict the initial value of human skin temperature with the influence of the metabolic heat generation and the blood perfusion. It is discovered the skin temperature of the human subject experiment fluctuates. However, the result obtained from the model remains unchanged until the simulation ends. The predicted results from the model were well in agreement with the experimental results with an acceptable error of 1.05%.

Thermal comfort is the human subject perceive satisfaction to the work environment. The thermal comfort need to be achieve towards productive working environment. The comfort level of the subject is affected by the human skin temperature. To assess the skin temperature with the sorrounding by conducting human experiment in the climatic chamber. It is rigorous and complex experiment.This study was developed to predict human skin temperature in comfort level with the finite element method and the bioheat equation. The bioheat equation is a consideration of metabolic heat generation and the blood perfusion to solve heat transfer of the living tissue. It is to determine the skin temperature focussing at the human arm. From the study, it is found that the predicted skin temperature value were in well agreement with the experimental results. The percentage error insignificant with acceptable error of 1.05%.

Burn injury is one of the most common injury among firefighters. Moisture comes from perspiration or hose spray absorbed in the personal protective clothing and steam burn injury occur with continuous heat exposure. The heat transfer from the heat flux is enhanced due to transformation material properties that holds high thermal conductivity and heat conductivity. Finite element method is used to predict steam burn injury among firefighters. The model is developed in 1dimensional cylinderical quarter geometry representing the human limb. It is discovered the skin temperature 10°C increases with wet material than dry material. The pain threshold at the lower arm of wet material condition is formed 40second rapidly compare to dry material condition. The first degree burn occur at t=9.5second sooner than the dry condition t=25second. The skin temperature increases with the wet material resulting severe skin burn. It is found that the wet personal protective clothing had compromised its thermal protection. Therefore, firefighters will experience high risk of thermal hazard.

Firefighting is a life-threatening situation, they are exposed to extreme heat fire and explosion. Burn injury is the most common injury occur in firefighting. The firefighters are enforced to used personal protective clothing to protect them against fire. The purpose of the study is to assess the effectiveness of fire fighter’s personal protective clothing by utilizing heat transfer model in finite element analysis. The model applied bioheat equation to solve heat transfer through living tissue at muscle area with consideration of metabolic heat generation and blood profusion. The validation of the heat transfer model was performed by comparing the predicted and measured skin temperatures with an acceptable error of less than 20%. The study found the skin temperature increases significantly with the heat flux intensities. The heat flux of 1200W/m2 causes to skin temperature 38.3°C. Skin temperature will gradually rise at t = 0 second and approaches it’s steady at t =198 seconds. The maximum air gap thickness reduces the heat stress effect. The reduction of 1 mm air gap thickness contributes to an increment of 0.2°C of the skin temperature.

Vibration is a serious concern for tall structures during a natural disaster such as earthquake, wind storms, sea waves and hurricanes. The risk of occurrence of structural damage can be decreased by using a controlled vibration system to increase the damping characteristics of a structure. Damping is defined as the ability of the structure to dissipate a portion of the energy released during a dynamic loading event. The aims of this study are (1) to investigate a 4-storey 2D steel frame retrofit with viscous damper to reduce its vibration and (2) to demonstrate the performance of such a damper when fitted to a structure by analysis and tests the model. Therefore, a series of shaking table tests of the 4-storey 2D steel frame with and without viscous damper (VD) was carried out to evaluate the performance of the structure. The results of the experimental tests illustrate that viscous dampers decrease the structural responses of slender frame without changing their behavior on the shaking table. In other words, the displacement of the structure is reduced, however, there is no any transition of flexible to stiff structure related to its dynamic responses.

The main objective of this study was to obtain the correlation between the severity of damage to the stiffness of the frame in the format of its intrinsic dynamic properties, the natural frequency of the structural system at damaged and undamaged state. In this research, a laboratory test was performed on the precast post-tension frame of a similar dimension and strength specification to Jabatan Kerja Raya (JKR) school buildings. The modal frame is a reduced in scale of 1 to 5 and subjected to cyclic lateral loadings and monitored its frequency through vibration test. The vibration test was performed at each end of the cycle of a lateral pushover test. The vibration data was recorded by accelerometers due to external forced vibration to assess its natural frequency, mode shapes and damping values of the system. This research found that there is a physical tangible relationship between natural frequency changes and stiffness in the frame. The results showed that as the severity of damage increases, the natural frequency of the frame decreases significantly, indicating that softening of the system that lead to a favorable ductility for earthquakes.

New innovative Industrialised Building System (IBS) has been implemented in Malaysia. It is a sustainable approach, innovative technique and implements repetitive manufacturing using green materials. This paper presents one of the standard tests to check the design and strength of IBS components via an experimental flexural test and then verify the finite element analysis. One IBS frame was set-up, tested with two points of monotonic vertical loading, and analysed by Abaqus 6.12 software. The structural performance in nonlinear state was evaluated in load-displacement relationship of beam, crack pattern, mode of failure, and stresses at concrete and connection deformation to guide the further components inspection.

The article reports on a study to establish and identify key components which addressed to slip and fall factors. This paper aimed at determining leading factors of slip-fall incidents and ranked the factors. A survey was done using a sample of 100 manufacturing workers in manufacturing companies in Malaysia. Exploratory Factor Analysis (EFA) has been chosen to evaluate the manufacturing workers perceptions in determining slip-fall leading factors at their own workplace. In this analysis, Principle Components Analysis (PCA) with Varimax rotation method was used. 25 items for slip-fall factors were identified after EFA where the variables consists i) footwear factor (3 items), ii) contaminant factor (4 items), iii) flooring factor (3 items), iv) cleaning factor (4 items), v) environment factor (4 items), vi) individual factor (4 items) and vii) perception of risk (3 items). All the questions were generated based on manufacturing workers perception on slip-fall factors. This finding is important to further study the influence of these factors to the workers in any other industry or workplace.

The main goal of this paper is to develop a framework to support the supplier selection process in an Iranian automotive industry. Although numerous criteria are being used for the selection of suitable supplier, selection of the critical factors in conformance to the specification of the automotive industries is less investigated. In order to fill this gap, this research was carried out to systematically propose a framework comprising of the most critical factors for the aim of supplier selection. A literature survey was conducted and measures for assessing the suppliers were extracted. Nominated Group Technique (NGT) was deployed to extract the most critical performance measures from the initial list. Seven measures were found to be proper for the supplier selection process. A Fuzzy Analytical Network Process (FANP) was then proposed to weight the extracted measures and determine their importance level. The model was then implemented to assist an automotive company for the aim of its supplier selection.

Production and distribution planning might come as one integrated system or separately managed. The distribution planning may include the storage and handling of products, transportation and delivery of products, and so on. Some industries may have inventory/distribution network which are very complex, due to its distribution network and may also be subjected to specific routing restriction. The restriction may affect the optimization of the performance of the distribution network. The aim of this paper is to present a conceptual model which minimizes the total distribution cost for a multi production plant, multi distribution center and multi retailers under seasonal demand and multi time period. The supply chain under consideration comprises of multi role nodes as the production plant and/or distribution center.

Every year earthquakes, tornadoes and other extreme windstorm cause fatalities or even kill people, devastate and millions of dollars worth of property. The likelihood that a tornado will strike building is a matter of probability. The study describes the analysis and design, the engineering process the new type of tornado safe room (Fig. 1) according to the FEMA guidance. It also evaluates the effects of in-fill frames and the linear response of reinforced concrete braced frames and comparison with frames with shear wall. The main conclusion drawn from this study is to elaborate that the masonry in-fills, are strongly influence the structural seismic response and contribute to the overall stiffness and can decrease drifts and displacements. Infill walls have significant role in the strength and ductility of RC framed structures and should be considered in both analysis and design globally. These walls make the structure significantly stiffer, and reduce the natural period of the structure. Locally, infill walls changed the load path, the distribution of forces between different elements of the structure, and the change the demand of forces on their adjacent elements of the bounding frame. Due to the high relative stiffness of the infill frames, they act as the main lateral load-resisting system and attract larger portions of the earthquake and tornado induced inertia forces.

The relationship between coefficient of friction (COF) and roughness is best found using tribology approach. This study used experimental design to collect and measure the data on COF and the roughness measurement under contaminated condition. It particularly measured the COF of four different floor surfaces in five surface conditions—one dry condition and four liquid-spillage conditions. For slipperiness measurement, the analysis of variance (ANOVA) was used to determine the effect of floor, footwear, and surface condition on the measured COF. Duncan’s multiple range tests was performed to determine the sample of means that is significantly different from others. Meanwhile, Pearson’s correlation coefficient was used to measure the strength between COF and the roughness parameter.

There are several factors that prompt the slip-and-fall incidents and this study focuses on seven factors. Epidemiology approach was used to determine the factors of slip-and-fall incidents, and questionnaire was selected as an instrument for data collection. Exploratory Factor Analysis (EFA) was performed to evaluate how the respondents perceived the slip-and-fall factors while Cronbach’s alpha was used to assess the internal consistency for each domain in the survey. Subsequently, the factors were ranked in accordance with the total variance recorded.

In this study, psychophysics (the subsets of human-centred approach) which includes the perception of slipperiness with visual and tactile cues (Chang et al., Ind Health 52:379380, 2014 [1]) are important to validate human perception of slipperiness. Subject rating was used as an instrument for data collection in human-centred approach. This study measured the perception of four different floor surfaces in five surface conditions—one dry condition and four liquid-spillage conditions. The concerned tested floor surfaces were (i) ceramic I (glazed ceramic tile), (ii) ceramic II floor (unglazed ceramic tile), (iii) epoxy floor, and (iv) porcelain floor (homogenous tile). Chi-square test was used to test the subjective scores of the floor slipperiness while Spearman’s rank correlation coefficient was used to measure the strength of association between the subjective scores of floor slipperiness and the measured COF.

Industrialised Building System (IBS) is a unique construction technique that has been implemented in many construction fields all around the world. However, its implementation in Malaysia is still slow and not effective. Through the research on IBS, some elements are found to be important and need to be improved in order to produce better quality components. One of the important elements is the design and innovation of IBS components by applying new interlocking configuration between blocks and by using a clamping bolted connection to the system. The main objective of this research is to determine the structural behavior of IBS block works sub-system under push over cyclic loading in comparison with conventional sub-system and to verify that the IBS interlocking geometry sub-system perform better than other sub-systems via laboratory tests. In this research, a block work assembly to form building sub-frame that integrated by two beams, two columns and infill system were built and tested to failure. Two types of IBS block work sub-systems with original geometry and interlocking geometry with scaled of 1:5 were tested with Push Over Cyclic Load Test. In comparison, a control model of Conventional Sub-System was also tested and analysed using the same methods. The results showed that the IBS geometry model with interlocking configuration performed better in terms of stiffness, ductility and flexibility of the models. The IBS original geometry model is ductile but lack structural stiffness while the conventional model is stiff but not ductile.

Tsunamis and hurricanes cause a lot of damage to structures. The water-borne debris that is produced during these natural disasters can cause a considerable damage to the many structures if they have not been constructed for such loads. Tsunami field survey observations have indicated that the damage is aggravated by heavy objects like wooden logs, automobiles, boats, storage barrels and other containers. This paper presented the results of experimental study for the quantification of the debris impact force on the structures. Moreover, it studied the formulas, which have been specified in the recently published tsunami- resistant engineering design guidelines (FEMA P-646, 2012) and the Coastal Construction Manual (FEMA P- 55, 2011) with the results of experiment.

The new construction method known as Industrialized Building System (IBS) offers several benefits compared to the Conventional Building System (CBS); however, IBS is perceived by most of the practitioners to be an expensive method for being utilized in construction industry. Whilst relatively numerous studies have been carried out on the subject of IBS and CBS methods, there has not been any exploiting building information modeling (BIM) as a useful tool to calculate quantities, time, and cost needed to construct building with each of the two aforementioned methods. The aim of this paper is to calculate cost of two similar buildings (one is constructed with IBS method and other one with CBS method) and compare them in terms of economy based on a chosen case study and same initial investment. To this end, the construction cost of buildings is calculated using BIM software, namely Revit Architecture and Navisworks Manage for modeling the chosen case study and estimating construction cost, respectively. The findings indicated that IBS was not economic in low investment of company; however, with investment on more than 100 units of IBS, this method was shown more economical compared to CBS method. In addition, the initial investment on IBS method could be returned when more than 200 units of IBS were implemented in the projects.

A generic representation of linear and curvilinear entities with embedded motion attributes is possible via the integration of a Hermite curve and dynamic of motion. A Hermite curve will form the curve, while a dynamic of motion will position the vertices on the curves with the introduction of a delta distance (Δs). A three-phase algorithm is introduced to examine the applicability of generic representation in tool-path generation. The preprocessing stage will examine the input model prior to Phase I. Phase I will extract the BReps data, and these BReps data will be used in Phase II to develop the generalized mathematical representation of the tool path. Finally, the tool path is drawn in Phase III.

To understand the risk of slipping accidents in the industry, it is imperative to measure the coefficient of friction (COF) between footwear and floor. In this study, COF values were measured for four types of floor with five surface conditions that represent dry conditions and four liquid spillage conditions. A portable skid-resistance tester was used to measure the COF with three footwear materials attached on the slider. The results show that the interaction between floor type, footwear material, and surface conditions was significant (p< 0.0001). Variation of COF value was found due to different footwear materials and floors involved during the interaction. The friction loss results also conclude that the COF became reduced significantly in all footwear-floor conditions (in the range of 17% to 78%) in the presence of spillage on the floor.

This paper presents a perishable product recovery model that aim to maximize the total recovery value of the return product. The perishable product under consideration has a property of quality degradation over time and can be reprocessed. The proposed model are expected to decide which, when and how does the return product being retrieve from the retailer.

Currently, design and machining features diverge in meaning, even when they are interpreting the same object. This divergence of feature interpretation provides a venue for research work to reduce the complexity that arises in recognizing interacting machining features. Therefore, this paper demonstrates the recognition of design features with the aim to eventually decompose the interacting machining features. Loop driving recognition links the CAD data directly to the features to be recognized. The first step is to recognize the design features from B-Reps part. Then geometrical reasoning on these design features is employed to convert the design features to its respective machining features. The process of conversion is in fact the process of decomposing the interacting machining features without having to visit the B-Reps data again. The system takes into account the nesting of the design features that causes more interacting machining features to be decomposed. Finally, output data of both design and machining features are then displayed.

Musculoskeletal disorders (MSDs) have been recognized as one of the main occupational health problems among health care workers. Many studies have suggested the influence of psychosocial factors on MSDs. The objective of this study is to look into the association between psychosocial factors and the prevalence of MSDs symptoms among internship doctors. 86 internship doctors completed a questionnaire which consists of demographic data, physical and psychosocial factors as well as musculoskeletal discomfort. Results show that 32.6% of them reported that they have musculoskeletal discomfort at a single body region during the last year, 16.3% reported two regions and 9.3% reported three regions where the most prevalent region affected was the neck area where 27.9% of the respondent reported they experienced symptoms or pain in this region, followed by wrists / hands (26.7%), lower back (19.8%) and upper back (14.0%). Meanwhile, there were association found between psychosocial factors and prevalence of MSDs in certain body regions. For instance, musculoskeletal symptom at neck, wrist/hands, upper and lower back regions have been found to be associated with five psychosocial stressors examined in this study. The results obtained indicate the influence of psychosocial factors on MSDs.

Keeping track of tools is essential for smooth running of any production unit. Being one of the critical resources for production, non-availability of tools can affect productivity of any manufacturing shop floor seriously. In this paper, a novel tool-tracking system, which can be used to monitor the movements of tools in a shop floor to prevent tool loss and tool hoarding, is described. The system uses miniature transmitters embedded in the tools together with a number of receiver stations located strategically around the shop floor. Each tool intermittently transmits a coded signal so that it may be identified as well as located. Simulation studies show that the system is effective particularly in situations where the productivity would have been low because of high tool losses.

Sistem Rapid Prototyping (RP) ialah teknologi yang menukar sesuatu reka bentuk yang dibina dalam Computer Aided Design (CAD) ke suatu komponen model 3D. Model CAD biasanya dibina dalam sistem CAD yang kemudiannya dihantar ke sistem RP. Antaramuka yang baik antara sistem CAD dan sistem RP adalah salah satu faktor penting dalam menghasilkan prototaip yang berkualiti tinggi. Kertas kerja ini melaporkan hasil uji kaji yang dijalankan untuk mengenal pasti masalah-masalah dalam memindahkan data antara satu sistem CAD (UNIGRAPHICS) dan satu sistem RP (QUICKSLICE). Berdasarkan hasil uji kaji dan analisis yang dijalankan, satu garis panduan dicadangkan untuk perpindahan data yang lebih berkesan antara sistem CAD (UNIGRAPHICS) dan sistem RP (QUICKSLICE). Kata kunci: CAD; CAM; CAD/CAM; Rapid Prototyping Rapid Prototyping (RP) is a technology that transform a design generated in Computer Aided Design (CAD) to a 3D model parts. CAD models are usually done on a CAD system and then transported into the RP system. A good interface between the CAD and the RP system is one of the key factors of producing a good quality prototype. This paper reports on the results of an experimentation carried out to identify the problems in transferring data between a CAD system (UNIGRAPHICS) and an RP system (QUICKSLICE). Based on the experimentation’s results and analysis, a basic guideline is proposed for a safer data transfer between the CAD system (UNIGRAPHICS) and an RP system (QUICKSLICE). Key words: CAD; CAM; CAD/CAM; Rapid Prototyping

Automasi pengecaman ciri adalah satu komponen yang kritikal dalam mengintegrasikan CAD/CAPP/CAM. Aturcara pengecaman ciri perlu dilaksanakan dalam perancangan proses supaya keputusan berkaitan dengan aktiviti perancangan proses boleh dibuat. Berbagai kaedah telah dibangunkan untuk mengautomasikan pengecaman ciri. Kertas kerja ini membentangkan satu pendekatan kepada pengecaman ciri menggunakan rule based yang berdasarkan sifat-sifat tertentu sesuatu ciri seperti jumlah permukaan, jumlah bucu, jenis muka, dan sifat-sifat lain ciri seperti lekuk/cembung. Kaedah yang dicadangkan dilaksanakan menggunakan Graphics Interactive Programming (GRIP), dan permodelan padu Unigraphics. Hasil ujian menunjukkan bahawa pendekatan yang dikemukakan dapat mengecam ciri yang mempunyai satu set sifat-sifat yang unik. Pendekatan ini juga ringkas, mudah difahami dan digunakan. Kata kunci: CAD, CAPP, CAM, model padu, ciri, pengecaman ciri Automated feature recognition is considered a critical component for integration of CAD/CAPP/CAM. The automation of process planning requires the implementation of a feature recognition procedure, so that decisions relating to steps of process planning activities can be made. Various methodologies have been developed to automate feature recognition. This paper presents an approach to feature recognition using rule based on different characteristics specific to each feature such as the total number of faces, the total number of edges, the type of faces, and the attribute of feature i.e. protrusion/depression. The proposed method is implemented using Graphics Interactive Programming (GRIP) and Unigraphics solid modeler. The results show that the proposed technique is capable of recognizing features with a unique set of attributes. The rule is also simple, easy to understand and implement. Key words: CAD, CAPP, CAM, solid models, features, feature recognition

In hot and humid climates thermal discomfort is a major problem to the occupants of many residential terrace houses especially when they are not equipped with an air-conditioning system. This paper presents a study on an assessment of the level of thermal comfort in a naturally ventilated residential terrace house in Malaysia using computational fluid dynamics (CFD) method. Actual measurements were made to obtain the average air temperature, relative humidity and air flow pattern in various sections of the house. CFD simulations were conducted on a simplified model of the house to predict and visualize the temperature distribution and air flow pattern and its velocity in the house. The level of thermal comfort in the house was found to be well outside the comfort limits as specified by ASHRAE standards.

Manufacturing companies are required to fulfill customer's driven imperatives such as on time delivery as well its own requirements such as high machine utilisation and low work in process. In order to achieve these, manufacturers need to adopt the right manufacturing strategy. Selecting the right manufacturing strategies will improve its capability to meet its customers demand as well as its own limitations. This research identifies five strategies that a job shop may adopt to achieve flexibility in meeting demand. The five strategies ranges from the basic strategy of having a complete set of single-operation machines to flexible multi-operation machines. Each strategy is evaluated and a set of guideline is proposed. The results show that when job tardiness and work-in-process is the performance criteria, the duplication strategy is the best. However, if the performance criteria is machine utilisation, then the best strategy is the replacement strategy. Abstrak. Syarikat pembuatan bukan sahaja perlu memenuhi keperluan pelanggan seperti penghantaran yang menepati masa tetapi juga perlu memenuhi keperluannya seperti penggunaan mesin yang tinggi dan tahap kerja separa siap yang minimum. Bagi mencapai matlamat ini, syarikat perlu menggunakan strategi yang sesuai. Penggunaan strategi yang sesuai dapat memperbaiki kemampuan syarikat pembuatan untuk memenuhi kehendak pelanggan dan juga kehendak syarikat pembuatan. Kajian ini mengenal pasti lima strategi yang membolehkan bengkel kerja menjadi fleksibel. Kelima-lima strategi ini merangkumi strategi asas yang melibatkan satu set lengkap mesin-mesin satu operasi hingga ke mesin-mesin berbilang operasi. Setiap strategi dinilai dan satu garis panduan dicadangkan. Hasil kajian menunjukkan bahawa strategi penduaan ialah yang terbaik jika kriteria prestasi yang dikehendaki ialah kelewatan dan kerja separa siap. Tetapi jika kriteria prestasi yang dikehendaki ialah tahap penggunaan mesin, maka strategi penggantian ialah yang terbaik. Kata kunci: Ukuran prestasi, bengkel kerja, strategi pembuatan