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Reinforced concrete (RC) is the most preferred construction material for the civilian structural construction such as building and bridge because it is economical to build and possesses high strength. There have been several verified numerical studies on RC, but most have all been limited to the scope of a small rectangular or small square RC panel clamped at the edges. As a result, there is still a need for a complete RC structure for example RC wall with its foundation to represent as a single stand structure. With available validated complete RC structure experimentally and numerical data on blast pressure profile, detail numerical study is possible to investigate in depth. In AUTODYN commercial software, arbitrary Lagrange Euler (ALE) solvers are used to analyse the interaction between air and RC wall structure. The RC walls were built with the same moment resistance but a different hooked direction on vertical flexural steel reinforcement into the foundation. The numerical result indicated that in the hooked-in direction, the average strain at the back side of the wall peaked at 1.0625×10-3 at first 5 msec after impact, which is half of what it was in the hooked- out direction. Furthermore, the numerical simulation coincided with the experimental findings, where the proper steel arrangement for the RC wall subjected to blast was hooked-in.

There has been no significant efficacy in treatment for osteosarcoma (OS) metastasis after nearly four decades of trials. This motivates us to elucidate OS therapies according to their four bidirectional mutation stages. To refresh the OS therapy status quo, the historical developments and clinical advancements are briefly described. However, the main issue of metastasis remains unresolved, accounting for 90% of pulmonary metastasis deaths. Thus, this metastasis problem is related to immune evasion and chemoresistance that are being induced after long-term treatment by the use of immunotherapy for tumorigenesis. Therefore, it is rationale to discuss the relationship cycles of mutation stages including tumorigenesis, metastasis, immune evasion, and chemoresistance. Even though many combinational and targeted therapies have been developed to intensify these mutation treatments, successful clinical translations with higher cure rates are still rare. Through this review, an in-depth understanding of the bidirectional relationship between the four OS mutation stages and their respective therapies is provided. Herein, we summarise the medicines used to treat tumorigenesis, including COLGALT2 inhibitors, Tra2B, and AGAP1, miR-148a and miR-21-5p EVs, and the lncRNA LIFR-AS1. Following the medicines used to treat metastasis are AXL, miR-135a-5p, mRNA BCL6, TGFβ1, Tim-3, SOCS5, CASC15, KLF3-AS1, PDCD4, ATG5, and Rab22a-NeoF1. Then the medicines used to treat immune evasion are N-cadherin, anti-IL-9, USP12 inhibitor, IgG-4+ B-cells, LAP inhibitor, anti-Wnt2 mAb, anti-αvβ8 integrin, HK2-mediated IκBα, IDO inhibitor with NO, and TGF-βRII with anti-IgG1. Finally, the medicines used to treat chemoresistance are DHFR, FPGS, HSP-90AA1, XCT-790, ATKI, and IGF1. As a result, this contribution is expected to serve as a reference and guide for scientists and clinicians.

Reinforced concrete (RC) widely used as the construction material for the main structural element for many significant structures such as bridge and building because of its relatively high strength and economical. However, there still lacks research published regarding the appropriate reinforcement steel arrangement in a complete RC structure subjected to blast load. Most of the published experimental works focused on the small rectangular or square RC panel. From the record search, the approved design by professional engineers, when RC wall subjected to the possibility of blast load, both RC wall details either retaining wall or shear wall implemented. Therefore, the full-scale blast experiment is vital to appraise the appropriate steel reinforcement arrangement in the RC wall. The blast experiment indicated, with different steel reinforcement arrangement in the RC wall, the better blast resistance with the number of cracks on the RC wall is significantly less from one another for the wall with the arrangement of horizontal flexural reinforcement tied-outside the vertical flexural reinforcement and the hooked-in direction of vertical flexural steel reinforcement into the wall base.

Shaped charge (SC) is a mechanism used by defence industries as anti-armored weapon to penetrate armored plates. Numerous studies have been conducted on the shaped charged effects. However, experimental studies are limited due to great safety requirement and limited access to high grade explosive. Due to these limitations, an experimental study on a small-scale shaped charge mechanism (SCM) penetration blast test was conducted against five (5) types of target materials. The experimental data is then verified by simulation to proof that it can be used to predict the SC penetration data. This paper intent to present a comparative study on the effect of shaped charge blast conducted by simulation with the actual experimental results. In order to conduct this study, a 2D AUTODYN software were used to develop the SC blast model against five (5) types of target materials. This study concludes that the 2D AUTODYN simulations results can predict the hypervelocity penetration for all target materials compared to the experimental test with an average difference of 9.1 %.

Lifelong learning is an important factor in raising the level of knowledge and skills and improving the quality of life. For entrepreneurs, lifelong learning is the basis of long-term success because it encourages them to become open, creative and innovative leaders. Despite being said to be the solution to the narrowness of future job availability, entrepreneurship is still did not get enough attention from the students, whom are the future worker themselves. Past researches had reported that the students are lack of motivation and research related to the motivation factors also said to be scarce. On the other hand, studies regarding lifelong learning in education system had indicated several issues including lack of implementation of lifelong learning including level of student, low usage of teaching approach towards lifelong learning and lack in skills related to lifelong learning. Therefore, this study focuses on undergraduate students and aims to understand their entrepreneurial motivation in light of lifelong learning or whether their motivation is influenced by it. This study had adopted a quantitative research method. Total of 393 Bachelor Degree students from a public university in Malaysia had involved as the respondents selected through random sampling method. Data analysis was done using descriptive analysis and multiple linear regression. After the analysis, it shows that lifelong learning characteristics and lifelong learning tendencies were both able to explain 14.4% of the variation of entrepreneurial motivation and statistically significant (R2 = 0.144; F (2, 390) = 32.88, p = < .000). It means that the independent variable is statistically significant in predicting the dependent variable. Lastly, it is in the hope that this research can be a guide for the nations in producing a quality graduates that can become successful entrepreneur.

The energy ship is a concept for offshore wind energy capture which has received very little attention until today. To this date, there had not been yet an experimental proof of concept. In order to tackle this issue, an experimental platform and data acquisition system has been developed. A 5.5m long sailing catamaran served as a platform equipped with a 240mm diameter water turbine. The energy ship platform has been tested several times in the actual river to investigate the workability of the platform and data acquisition system. Results show that energy ship platform can produced 500W electric power for a true wind speed of 10 knots.

Powder metallurgy metal matrix composites based on AZ91 alloy matrix reinforced with 0.3, 0.6 and 0.9 weight percent of multiwall carbon nanotube (MWCNT) were investigated from the point of view of their response to artificial ageing as compared to the unreinforced AZ91 matrix alloy. Mg-Zn-Al (AZ91) and its composite were prepared by milling the raw materials and followed by sintering at 450°C for 2 hours. The sintered samples were solution treated at 415°C for 2 hours and followed by artificial ageing at 175°C. The ageing behavior was monitored by following the phase analysis and hardness of the samples examined. Microstructure of the sintered composites indicated that MWCNT was embedded in the AZ91 matrix alloy. All composites indicated lower hardness than matrix, however AZ91reinforced with 0.6 and 0.9 weight percent of CNT showed accelerated ageing. X-ray diffraction pattern indicated the present of β-phase (Mg17Al12) that responsible for the hardening behavior.

A digital image is basically formed together with metadata which describes the image such as information about the file (e.g. location captured, author, date, time and etc.), tags and keywords. These properties allow images to be stored accordingly to its categories in a database. Those images later can be retrieved from the system by running a text-based query which explained the characteristics of an image. Although retrieving by text-based query method is a common and widely used to find images in a very large database, this method however does not guarantee that the results returned is as described in searching query due to the fact that it is totally dependent on the accuracy of stated image properties. In order to improve the accuracy of the text-based retrieval method, a Content-Based Image Retrieval (CBIR) has been proposed as a complement to the standard method.

This paper study the mechanical properties behavior of metal plates against hypervelocity penetration caused by shaped charge. Five different materials were used as target specimen fabricated from welded stacks of material plates, namely Rolled Homogeneous Armor (RHA), Hardox-500, mild steel, aluminum and brass. Specimens had undergone an initial monolithic test consist of tensile tests and microstructure observations, followed by series of hydrodynamics penetration blast tests using shape charge mechanism. Results from blast test shows that the least penetrated specimen is RHA (58mm) followed by Hardox-500 (92 mm), mild steel (110 mm), Brass (155 mm) and aluminum 238 mm). Comparing these with the specimen yield strength from the tensile test results shows that Hardox-500 has higher yield strength (Sy) followed by RHA, mild steel, brass and aluminum, which are 1370 MPa, 1320 MPa, 280,221 respectively, which are not inversely proportional to the penetration. However, the ultimate tensile strength (Sut) where the RHA were the highest followed by Hardox-500, mild steel, brass and aluminum, were inversely proportional with the depth of penetration. The penetration results also show consistence relation with energy absorption.

This paper describes the proposal of Poka Yoke Roller Coaster (PKYC) jig as a device to detect nut weld missing of door patch base line model (BLM) at assembly line station. The PKYC was proposed in order to detect nut weld missing problem and to reduce cycle time and manpower that lead to higher cost by applying quality management concept as a problem-solving tool. This special purpose tool was capable to meet specific job based on industrial need by providing repeatability, interchangeability and accuracy in the manufacturing of products. A Quality Control (QC) approachcalled the Zero Quality Control (ZQC) was used to achieve zero defects at production line. In order to reach zero defects, poka yoke method was applied in this research. Outcomes indicate that PKYC can be utilised as a custom-tailored jig for detecting nut weld missing as well as fulfilling other objectives.

A temperature recorder system is based on the changes of the patients’ temperature over a fixed time that uses the advantages of a smartphone. This paper proposes a wirelessly controlled system to achieve reliability and mobility of the user. The wireless system was achieved by utilizing a smartphone, PIC Controller and Bluetooth to a device that’s been installed with the temperature sensors. This system can be used for medical purpose to monitor and record 24/7 of the patient’s temperature consistently which can systematically save manpower, time and lives.

The paper describes a work focused on the process of perforation of aluminum sheet. A numerical investigation has been carried out to analyze in details the perforation process subjected to normal impact by different nose shapes of projectiles. The perforation process has been simulated by the application of 3D analysis using IMPACT dynamic FE program suite. The comparison on failure modes depending on the projectile nose shape have been studied and evaluated. An appropriate constitutive relation was applied to describe the material behavior of the aluminum sheet. The study covered different failure modes including petalling, plug ejection and circumference necking of perforated aluminum sheet according to different level of impact velocity ranging from 100 m/s to 600 m/s. In this investigation, a special attention will be given on the deformation and failure.

Penetration is the basic element of designing protective concrete structure against the local impact damage of hard missile. Impact energy is the dominant cause of damage in moving accidents. When hard projectile collides with concrete target, it is the impact energy of the projectile that makes concrete target to deform. Therefore, it is vital to study critical impact energy required to causes penetration. An analytical model is developed to predict the required critical impact energy for maximum penetration without rear effects in concrete slabs when it is impacted with hard projectile. The nose shape factor Ni also has been introduced with inclusion of empirical friction factor Nf, as modification in Chen & Li nose shape factor for ogive nose hard projectile. The newly developed analytical model and nose shape factor Ni is examined for CRH = 2.0, CRH = 3.0, and CRH = 4.25. It was found that the predicted results from analytical model with nose shape Ni are in close relation with experimental data in all cases as compared to predicted results with traditional Li and Chen nose shape N*. In, General, the analytical model generates encouraging prediction which is consistent and follows a general trend of experimental results.

The effects of geometrical shapes are believed to play significant role in the deformation of metal foams under impact loading. This research was carried out to investigate the deformation behaviour of a single cellular cell of metal foam with different geometrical shapes. The simulation analyses were done on various two dimensional shapes with the consideration of the material properties. Two parameter values had been studied to determine the dynamic deformation behaviour of various geometrical shapes i.e. the internal energy and kinetic energy. It is found that, the geometrical shapes have shown significant effects on the dynamic deformation of single metal foam cell. It is hoped that this study could contribute significant result to the research of the metal foams especially in analyzing the shape effects to the behaviour of the metal foam under impact loading.

In relation to the conventional concrete then foamed concrete (FC) is weaker. Therefore FC was added by Rice Husk Ash (RHA) to alter the strength without eliminating its characteristic as aerated concrete. Actually function of RHA is substitute the sand partly. The strength of concrete affects to prevent the dynamic impact loading. However FC as aerated concrete can absorb energy impact by its porosity. Both of characteristics were presented in this investigation. SEM and EDS detected that pozzolanic reaction was done when FC was processing hydration of cement in admixture. The presence of RHA increased the strength of concrete owing to cement hydration process and pozzolanic reactivity of RHA. The result of impact loading on slab FC target displayed that FC with RHA was more shallow than without RHA. Beside of that local damage showed that FC with RHA denser and is not impression of fragments than FC without RHA.

This paper presents a review of recent developments of nonlinear constitutive material models for the applications in high speed ballistic impact of projectile into several types of targets. The objective is to comprehend some numerical approaches that have been proposed and used in the technical literatures especially regarding bullet-target interaction. Attention is given on the application of several types of computational constitutive models and simulations used to represent the projectile characteristic, ballistic penetration, failure modes in target and deformation pattern. This paper serves as a concise source to identify future direction in the area of computational mechanics of high speed collisions and provides brief literatures for those interested in conducting research into the topic.

Foam-filled enclosures are very common in structural crashworthiness to increase energy absorption. However, very less research has been targeted on potential use of natural/recycled material reinforced foam-filled tubes. Therefore, an experimental investigation was performed to quantify energy absorption capacity of polyurethane (PU) composite foam-filled circular steel tubes under quasi-static axial loading. The thickness of the tubes was varied from 1.9, 2.9 and 3.6 mm. The tubes were filled with PU composite foam. The PU composite foam was processed with addition of kenaf plant fiber and recycled rubber particles that were refined at 80 mesh particulates into PU system. The density of PU resin was varied from 100, 200 and 300 kgm-3. The PU composite foam-filled tubes were crushed axially at constant speed in a universal testing machine and their energy absorption was characterized from the resulting load-deflection data. Results indicate that PU composite foam-filled tubes exhibited better energy absorption capacity than those PU foam-filled tubes and its respective empty tubes. Interaction effect between the tube and the foam and incorporation of filler into PU system led to an increase in mean crushing load compared to that of the unfilled PU foam or tube itself. Relatively, progressively collapse modes were observed for all tested tubes. Findings suggested that composite foam-filled tubes could be used as crashworthy member.

In the present work polyurethane foams containing various content loadings of kenaf fiber and recycled tire rubber particulates were prepared and studied, with the objective of developing alternative composite rigid foams. The influence of the filler content on the foam microstructure and its physical and mechanical behavior has been studied for three different polyurethane resin densities. Microstructural observation on fracture surface of composites was carried out using scanning electron microscopy. It has shown closed spherical cells with reduced size when the fillers are added. Nevertheless, the incorporation of kenaf fiber and recycled tire rubber particulates that refined at 80 mesh led to higher mechanical properties than that unfilled polyurethane foam. A 6% filler content loading exhibited the optimum compression stress and compression modulus, while further increase of filler content loading resulted in decline in mechanical behavior. The presence of larger filler content deteriorated the polyurethane system cellular structure and lead to poor composites strength. Overall, the use of kenaf fiber and recycled tire rubber particulates gives composite foams with comparable mechanical behavior for the studied filler reinforcement level.

This project is about an experimental impact resistance and behaviour of sandwich panel structure, consists of steel plates and kenaf foam. The use of natural fiber reinforcement foam could give a great advantages in weigh reduction which very useful in military mobility and transportability. A standard rifle was used to launch a small bullet (5.56 mm) in constant velocity towards the sandwich panels. The experiments result is based on the depth of the indentation due to the penetration against the armour. The best specimen combining both parameters of study is 20% of kenaf with 45 mm thickness because it can resists the most impact from the bullet. Therefore, it can be concluded that using kenaf to reinforce the polyurethane is success in enhancing its strength and mechanical properties.

Foamed concrete as favorable substitution conventional concrete can be used in wide range of constructions. Usage the Polypropylene Fibre (denoted as PF) in this investigation examined contribution of PF on strength of foamed concrete. Mechanical test were performed to measure effect of PF on improving compressive and splitting tensile strength. Results indicate that PF significantly improving compressive and splitting tensile strength. Behavior of PF where drawn into foamed concrete similarly with normal concrete. The fibrillation and interfacial bonding between PF and matrix has been occurred and reduced the micro crack of matrix and prevented propagation crack growth. However influence of porous of foamed concrete is considered. Process of curing continuation 60 and 90 days indicate that interfacial adhesion is wider when cement hydration process is running. Scanning Electron Microscope (SEM) exhibits condition microstructure of foamed concrete added by PF alter the microstructure, especially interfacial bonding between PF and matrix.

In this research we investigate the possibility of enhancing the way brick walls can be retrofitted in an economical manner and become more resistant to blast impact. Retrofitting a method usually done on constructed walls; however, the same strengthening procedures can also be applied to a new construction project. In this research we investigate three methods of reinforcing brick walls against blast impact. First, reinforcing the brick layer using carbon fiber strips only without epoxy, with the fiber being placed on the bare bricks before it is plastered with mortar finishing, second, reinforcing the brick wall by placing CFRP onto the bare bricks and fixing with epoxy prior to finishing or being plastered over with mortar, and third, retrofitting the outer surface of a finished, or plastered, brick wall with CFRP and fixed with epoxy as is commonly done. The impact test was conducted using a drop weight released at a fixed height to simulate blast energy of an explosion. The effects of the test on all the samples were observed to identify failure patterns. Flexural testing was also conducted to observe how the samples perform under normal flexural loading. It was discovered that the second option, i.e. placing the CFRP on the bare bricks and fixing with epoxy before it is finished or plastered over with mortar, performs the best. This is due to the CFRP being firmly fixed before mortar finishing, causing the CFRP to be held steadily in place during the impact, thus, helping the wall to resist the impact load. With the third option, the CFRP was able to resist the impact but, as has been observed in other studies, the CFRP delaminates from the wall. The first option does not work very well since the mortar is unable to perform as well as the epoxy in holding the fiber to the wall to resist the impact force. Thus, for plastered brick walls, it is better suited for it to be reinforced by FRP under the finished mortar rather than on it, thus reducing the problem of delaminated FRP from the wall surface.

AZ91 nanocomposite was exposed to several heat treatment processes and the effect of precipitation hardening on hardness was studied as a function of time and temperature. The investigation shows the significant of time and temperature are the main role in the precipitation hardening process of the nanocomposite. Kinetics study show a deceptive activation energy of 21 kJ/mol of the AZ91 nanocomposite. A relationship was derived to predict the maximum hardness at given time and temperature.

Ethernet is now the dominant networking in the home and office environment. Advanced of the network technology and convergence of communications, control and computer enabled the Networked Control System (NCS). Industrial Ethernet (IE) is the applications of IEEE 802.3 standards with requirements of factory equipment and network protocols. The connection based on star topology for the real-time communication between a computer and PLC. Analysis of performance based on data transfer rate, packets speed, packets volume, sum volume (KByte), Central Processing Unit (CPU) usage, percent available Read Access Memory (RAM), available Read Access Memory (RAM) and Packet InterNet Groper (PING) are conducted. It is shown that packets speed and packets volume for two types of the computer is approximately same between computer 1 and computer 2.

Foldable structures are very important for the purpose of rapid construction and bridging system. Such structural element can be utilized in disaster relief operations. In the early days, portable structure such as military bridges were made from steel, causing the weight of the structure to be huge, subsequently it will be costly to operate. To overcome these problems, aluminium and metal alloy were introduced to reduce the weight of such structure. Use of composite material such as Carbon Fiber Reinforced Polymer (CFRP) emerges as a lighter alternative being considered to be the primary material for the portable structure. The use of the CFRP as a primary material is due to its high strength to weight ratio, thus make it lighter than steel and other alloy. In this research, a long-span portable structure is analysed and designed using finite element method. Several dynamic simulations are made to test various possible lay-up including use of core in order to increase strength and stiffness of the member. From the trials it can be concluded that with proper design and fabrication, CFRP is capable of carrying the designed dynamic load. Furthermore, use of core layers for top flange can improve the performance of the structure significantly, while use of core to the webs stiffen the webs against buckling and further improve the overall performance of the structure.

Mobile software application has become a part of today's lifestyle. This mobile app is designed to help society to be physically active. The application is named UPNM Cardio Fitness, and is developed on the Android platform. The original purpose of the application is to measure and analyse the level of cardiovascular fitness of 18 years old male Military cadet Officers through a 2.4 km run test. The application is based on a data base using Google Fusion Table that stores and analyses the data received. The application consists of two parts: information of the individual and their respective fitness norms that can be accessed either automatically or manually. The classification of the norms is obtained from the fitness norms of 120 male cadets aged 18 years old. The norms are grouped into five categories which are: Excellent, Very Good, Good, Moderate and Poor. The software consists of 5 hyperlinks which are the main page, individual information, test result, file and record. The application is created using MIT App Inventor Software and Windows 7. The creation of the application has enabled researchers particularly in the Science Training programme in UPNM to carry out tests as well as to identify the level of fitness of their trainees immediately, accurately, and systematically.

Problem statement: Concrete is basic construction material used for most of structures. However, the typical vital structures have to be designed as self-protective such as nuclear plants, power plants, weapon industries, weapons storage places and water retaining structures, against any threats like natural disaster tragedy incident or intentionally produced by horrible incidents such as dynamic loading, incident occurs in nuclear plants, terrorist attack, missile attack tsunami and etc. Approach: In modern science, the impact energies are crucial way to study the local impact effects on concrete structures. Results: The way in which the kinetic energy is distributed through the concrete target is also noteworthy in determining its response, with the influence of dimensional analysis of the non dimensional numbers. This study is concentrate on development of empirical formula for predicting penetration depth of ogive nose hard missile in to the concrete structures, with the effects of different CRH ratios of missile (CRH = 2.0, CRH = 3.0, CRH = 4.5, CRH = 6.0) based on critical impact energies, by using curve fitting dimensional analysis of non-dimensional numbers. Conclusions/Recommendations: For the verification, the proposed developed empirical formula was compared with other established formulae such as Modified NDRC formula, Hughes formula, ACE formula, UKAEA formula. It is expected that the outcome of the proposed formulae can be applied in design recommendations and design procedures, especially for determining the dynamic reaction of the target to foil penetration in terms of critical impact kinetic energy.

Many researches has been done on the lateral collapse of tube. However, the previous researches only focus on cylindrical and square tubes. Then a research has been done discovering the collapse behaviour of hexagonal tube and the mathematic model of the deformation behaviour had been developed [8]. The purpose of this research is to study the lateral collapse behaviour of symmetric octagonal tubes and hence to develop a mathematical model of the collapse behaviour of these tubes. For that, a predictive mathematical model was developed and a finite element analysis procedure was conducted for the lateral collapse behaviour of symmetric octagonal tubes. Lastly, the mathematical model was verified by using the finite element analysis simulation results. It was discovered that these tubes performed different deformation behaviour than the cylindrical tube. Symmetric octagonal tubes perform 2 phases of elastic - plastic deformation behaviour patterns. The mathematical model had managed to show the fundamental of the deformation behaviour of octagonal tubes. However, further studies need to be conducted in order to further improve on the proposed mathematical model.

Problem statement: Foamed concrete has become most commercial material in construction industry. People in industries were co me out with the new mix design of foamed concrete to meet the specification and the requirements need ed. Approach: This is because foamed concrete has the possibility as alternative of lightweight c oncrete for producing intermediate strength capabilities with excellent thermal insulation, fre eze-thaw resistance, high-impact resistance and goo d shock absorption. Results: Currently Standard test to measure the compressive strength of foamed concrete is using standard unconfined compressive t est. Several research has been conduct but the compressive strength using standard unconfined compressive test not capture true behavior of foamed concrete because it just achieved only low compress ive strength and sample under compression failed due to brittle collapse of the sample. This study w as analyzed the comparison between standard compressive test and confined compressive test. The confinement test introduced to prevent sample from brittle collapse. Foamed concrete cylindrical sample has been investigated under the standard compressive test for hard concrete (ASTM-C39). Based on the research, samples are produced under unconfined and confined condition. Analysis has bee n done and the result show that under standard compressive test, the sample failed due to early cr ack initiation and failed. Confinement condition wa s increase the compressive strength but this conditio n influence the result. Conclusion/Recommendations: Standard test is not suitable to capture the true behavior of foamed concrete, and to prevent the sample from brittle co llapse during the test, new testing method was introduced to capture the true behavior of foamed c oncrete which is using Quasi Static Indentation Test. This test can be used to study about the beha vior of foamed concrete before it can be implemented to its final application.

Problem statement: Reflectarrays provide a low cost and low profile s olution for antennas required for high gain applications but their use i s restricted in some applications due to the narrow bandwidth and high loss performance. These performance limitations can be attributed to different sources of reflectivity of the reflectarrays. This work provides a thorough investigation on the reflectivity performance of reflectarrays designed at 10 GHz using different dielectric substrates. Approach: The detailed analytical study of the characteristi cs and losses of the reflectarrays was presented and a number of dielectric substrates are used to design and analyze the reflectivity of the reflectarrays based on the analytical investigation which is validated by Finite Integral Method (FIM) . Results: The results showed that the dielectric material wi th lowest dielectric permittivity and loss tangent values (Teflon) demonstrates an optimum reflectivity performance when employed for the reflectarray design. Conclusion: It was concluded from this research that material properties significantly affect the reflectivity of the reflec tarrays and hence the bandwidth and loss performance can be pronounced improved by using a low dielectric substrate.

This paper presents the interrelationship equation to predict the deformations of square rolled homogeneous armor steel plate subjected to spherical shape trinitrotoluene charge by using finite element analysis software i.e. AUTODYN 3D. The investigation starts by producing computer simulation process using AUTODYN 3D so that a set of experimental tests deformations’ data of rolled homogeneous armor steel plate from a published work can be used to validate the computer simulations outputs and good agreements are observed. Parametric studies are then performed on the design parameters of the explosive and the rolled homogeneous armor steel plate, where the mass of the explosive and the thickness of the rolled homogeneous amour steel plate are varied and analyzed by using the AUTODYN 3D computer simulations. Curve fitting method is then performed to produce the interrelationship equation that could be utilized by researchers as an initial prediction method in determining the deformation of rolled homogeneous armor steel plate subjected to explosive charge and the interrelation equation is valid and can be utilized for a standoff distance of 200 mm, plate’s thickness of 15 mm to 30 mm and explosive mass of 1.5 kg to 10 kg.

Numerical predictions of responses of rolled homogeneous armour steel plates subjected to spherical trinitrotoluene blast loading plate are presented in this paper. Three simulation cases are modelled using a numerical simulation software, AUTODYN 2D in order to predict the plate deformations under blast loading effects of spherical trinitrotoluene high explosive charge. AUTODYN 2D utilises two dimensional modelling space or axisymmetric modelling space to simulate three dimensional actual experimental tests in order to speed up the computational processing time. Three main geometrical parts namely; air, trinitrotoluene and rolled homogeneous armour steel plate are modelled in AUTODYN 2D utilising the LAGRANGE and EULER element formulations’ solvers. Despite the limitations of the two dimensional modelling space utilised in AUTODYN 2D, the simulation results managed to give relatively good agreement (differences in the range of 9.91%-31.25%) with respect to the experimental results from a published paper.

The accuracy of numerical result depends on many factors, among which is the selection of appropriate element size. An optimum mesh size is capable in reducing the percentage error and computational time consumption. In this study, a numerical tool i.e AUTODYN 3D is used to determine the optimum element size for the soil barrier subjected to air blast load. The pressure results on barrier surface obtained through one third scale are able to produce results that are in good agreement with published experimental test data as compared to full scale simulation. In this study, the selection of mesh size 20 mm x 20 mm x 20 mm found considerably as the best element size for the case study of a rectangular soil barrier subjected to air blast load by using AUTODYN 3D software.

The purpose of this research is to develop a mathematical model of the collapse behaviour of symmetric hexagonal tubes. For that, a finite element analysis procedure was conducted using ABAQUS software to determine the lateral collapse behaviour of symmetric hexagonal of angles, and square tubes to compare the results with the cylindrical tube. Then, a new predictive mathematical model of the lateral collapse behaviour for the generalized symmetrical geometric tubes is developed based on rigid, perfectly plastic model and the energy balance method. The newly mathematical model was validated with the simulation method results. It was discovered that symmetric hexagonal and square tubes performed different deformation behaviour than the cylindrical tube. Square and symmetric hexagonal with tubes performed Type II deformation behaviour.Symmetric hexagonal tubes with performed Type I with the perfectly plastic collapse behaviour whereas cylindrical tube performed Type I with strain hardening deformation behaviour. The mathematical prediction model had managed to model the deformation behaviour of symmetric hexagonal tubes with but failed to model the square and symmetric hexagonal with tubes because it was the perfectly plastic model which suitable for Type I with perfectly plastic deformation behaviour.

This proposal investigates Selective Harmonic Elimination (SHE) to eliminate harmonics brought by Pulse Width Modulation (PWM) inverter. The selective harmonic elimination method for three phase voltage source inverter is generally based on ideas of opposite harmonic injection. In this proposed scheme, the lower order harmonics 3rd, 5th, 7th and 9th are eliminated. The dominant harmonics of same order generated in opposite phase by sine PWM inverter and by using this scheme the Total Harmonic Distortion (THD) is reduced. The analysis of Sinusoidal PWM technique (SPWM) and selective harmonic elimination is simulated using MATLAB/SIMULINK model

This work aims to determine the response and impact energy absorbing capability of the square hollow section (SHS) column with U-shape grooves, subjected to dynamic mid span loading. Geometrical parametric study i.e. width and depth of the grooves and spacing between grooves was carried out using non-linear explicit finite element package ABAQUS. Comparison between plain SHS column with grooved SHS column in terms of initial peak force (IPF), specific energy absorption (SEA) and crush force efficiency (CFE) was carried out. It was found that the depth and width of the groove and spacing between grooves have significant effect on the impact response of SHS column. The grooved column has a higher SEA, shorter crushing distance but slightly lower CFE as compared to the plain column. This would make the grooved column a better option when designing for side intrusion protection.

The finite element approach was used in the simulation analysis to solve many engineering problems. One of the accuracy factors of this method is dependent on the choice of appropriate element size or mesh discretization. Good mesh discretization can reduce the percentage of error; avoid the computation time approaches to non-practical limits and furthermore, produces the optimal results. The purpose of this study is to identify the best size of mesh elements to be used in the problem analysis using the AUTODYN numerical simulation. The fully clamped circular plate subjected to blast load as per experimental setup was modified and simplified in the two-dimensional (2D) simulation model; it will be seen as a clamped beam at both edges. Plate model were discretized to form nodal and element. The deformation or deflection result found to converge at certain value by increasing the total number of element discretization. Assumed that the deformation results were accurate at the converged state; it will be taken as reference to choose the finest size of mesh element. In this study, several mesh sizes been considered, and the appropriate optimum mesh discretization obtained at range of 0.5 mm to 1 mm.

Investigation of Rice Husk Ash (RHA) thoroughly under controlled burning is regular issue to obtain result to produce the amorphous silica that has high pozzolanic reactivity characteristic. This paper offered an observation about characteristic of ground and un-ground of un-controlled burning temperature RHA that were taken from rice millings in Muar, Johor Malaysia. Such tests as X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD), Particle Size Analysis and Specific Area Surface, Fourier Transform Infrared Spectroscopy (FTIR), and Scanning Electron microscope (SEM) were conducted in this investigation to carry out the characteristic of RHA samples. The results show that the RHA was consist approximately 89.90% of silica and the RHA possessed the amorphous particle were dominant than its crystalline part. This proves that the RHA has a big potential as a pozzolanic material considering the silica content and porous structure. In addition, particle size analysis decides whether the pozzolanic reactivity can be increased by grinding process.