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This report establishes a procedure or methodology to model and predict potential plastic crack on plastic housing at impact. A test rig is designed and fabricated to deliver tensile impact load to plastic tensile bar specimens and the final displacement on the plastic specimens at fracture are obtained. These values are used in the finite element analysis (FEA) simulation to establish thresholds to predict failure of product housing when impact loaded. Various notch sizes are introduced on the tensile specimens to study the effect of notch-induced crack. Similarly, the fracture displacements are also used in the FE modelling to obtain threshold. Dynatup drop dart test is also employed to study cracks on a multi-axial stress state. MASTER OF ENGINEERING (EEE)

The capability of fabricating reproducible porous structures directly without the use of organic solvents was studied. Biomaterials, such as Polyetheretherketone (PEEK), Polyvinyl alcohol (PVA) and Hydroxyapatite (HA) were experimentally used to build TE scaffolds using a commercial RP process, Selective Laser Sintering (SLS). MASTER OF ENGINEERING (MPE)

Two types of cracks are often encountered in engineering structural systems and these are the open cracks and the breathing cracks. Existence of open cracks often leads to the loss of physical stiffness, resulting in a mostly linear structure with reduced load bearing capacity and vibration frequencies. The development of breathing cracks not only reduces structural stiffness, but tends to render the otherwise linear structure to become nonlinear, due to their bilinear stiffness characteristics associated with open and closed states. The nonlinear structural vibration responses can then be investigated and potentially employed to detect and identify breathing cracks within a structural system. In the present study, breathing cracks are modeled based on fracture mechanics from which bilinear stiffness values are obtained. These values are then incorporated into finite element models to compute the first- and second-order frequency response functions (FRFs) based on a proposed correlation technique which is both very accurate and resilient against measurement uncertainties. The existence of well-defined second-order FRFs has been firmly established for the bilinear oscillator, as well as a cantilevered beam with breathing cracks. By expressing the bilinear restoring force as a polynomial series, analytical derivation of second-order FRFs of general structural systems such as the GARTEUR AG11 structure with breathing cracks has been established for the first time. Further, a method of identification has been developed to identify the physical parameters of breathing cracks using second-order FRFs. With these new developments that are presented in this paper, a solid foundation has been laid for the potential applications of higher-order FRFs to damage identification and assessment of general real structural systems. MOE (Min. of Education, S’pore)

International audience; We report on a smartphone spectrometer for colorimetric biosensing applications. The spectrometer relies on a sample cell with an integrated grating substrate, and the smartphone's built-in light-emitting diode flash and camera. The feasibility of the smartphone spectrometer is demonstrated for detection of glucose and human cardiac troponin I, the latter in conjunction with peptide-functionalized gold nanoparticles.

International audience; Acid-base thermochemistry of isolated aliphatic amino acids (denoted AAA): glycine, alanine, valine, leucine, isoleucine and proline has been examined theoretically by quantum chemical computations at the G3MP2B3 level. Conformational analysis on neutral, protonated and deprotonated species has been used to identify the lowest energy conformers and to estimate the population of conformers expected to be present at thermal equilibrium at 298 K. Comparison of the G3MP2B3 theoretical proton affinities, PA, and ΔH(acid) with experimental results is shown to be correct if experimental thermochemistry is re-evaluated and adapted to the most recent acidity-basicity scales. From this point of view, a set of evaluated proton affinities of 887, 902, 915, 916, 919 and 941 kJ mol(-1), and a set of evaluated ΔH(acid) of 1433, 1430, 1423, 1423, 1422 and 1426 kJ mol(-1), is proposed for glycine, alanine, valine, leucine, isoleucine and proline, respectively. Correlations with structural parameters (Taft's σ(α) polarizability parameter and molecular size) suggest that polarizability of the side chain is the major origin of the increase in PA and decrease in ΔH(acid) along the homologous series glycine, alanine, valine and leucine/isoleucine. Heats of formation of gaseous species AAA, AAAH(+) and [AAA-H](-) were computed at the G3MP2B3 level. The present study provides previously unavailable Δ(f)H°(298) for the ionized species AAAH(+) and [AAA-H](-). Comparison with Benson's estimate, and correlation with molecular size, show that several experimental Δ(f)H°(298) values of neutral or gaseous AAA might be erroneous.

Response of tendons and ligaments to the change of mechanical environment, i.e., remodelling, is a great concern of biomechanical and orthopedic research. Due to sports and traffic accidents, the incidence of injuries in the lower extremity is increasing. Surgical treatments are often required to repair these injuries. During and after surgery, the knee joint must be immobilized for a period of time, and because of the immobilization, load and stress applied to the knee joint are greatly reduced. In view of this, it is crucial to know the effects of stress deprivation on the structural, mechanical and viscoelastic properties of tendons and ligaments. Previous studies have shown that the reaction of the patellar tendon due to immobilization of a knee is greater and occurs earlier in immature rabbits than in mature ones. The tensile strength and modulus of the patellar tendons are markedly decreased by immobilization. In addition, a long period is required for recovery from a relatively brief period of immobilization. At present, the effect of knee immobilization on viscoelastic properties, such as strain rate dependence and stress relaxation, of the patellar tendons has not been thoroughly investigated. Therefore, the objective of this study is to quantitatively determine the effect of knee immobilization on viscoelastic properties of the rabbit patellar tendons, and compare the immature rabbits with the mature ones. RG 10/04

This report highlights the main research results done on the Applied Research Project ARC 1/94 entitled "High Performance Vision System for Robot Guidance". The principal objective of this project is to explore the use of emerging technology on active vision and parallel computing to develop a high performance real-time vision system which is both powerful and complete to enable practical guidance of robotic systems such as assembly robot or mobile vehicle.

The purpose of RG 22/97 is to develop a multi-mode topside control system that can be used for training/ rehearsal as well as for the control of an actual ROV. The vehicle will be enhanced with intelligent control to achieve autonomous and station keeping control abilities. With the inclusion of on board navigation and communication system, the vehicle should be capable of being a free ranging vehicle. The following principal objectives have been identified. These are : 1. To develop a ?training simulator? for the training of new URV operator to address the issues of high cost and training time required. 2. To investigate the integration and fusion processes of information provided by several internal and external sensors and communication systems. 3. To investigate the possibility of using a small URV to simulate the larger URV. 4. To provide a framework for further research work in the area of low speed fully autonomous URV.

Over the past decade, microscale flow characteristics have been known to deviate from conventional behaviour, owing to two main effects: the electric double layer (EDL) near the solid-liquid interface, and the viscous dissipation effect. In this study, both effects on pressure-driven liquid flow in a microcapillary are studied numerically and experimentally. From past reviews, it was found that viscous heating results in higher flow rate and lower friction, while EDL effect causes reduced flow and higher friction; somewhat contrary to the first?s. This analysis therefore works to study the interaction between these two effects. The results conclude that effects of EDL and viscous dissipation both affect microscale flow characteristics in different ways. The two effects are always present and contributing to the flow characteristics. However, under certain circumstances, one effect may be more significant than the other, leading the flow characteristics towards that phenomenon. Hence, the significance of each effect depends on the physical flow conditions of the fluid.

The purpose of the RG 93/98 is to explore the most economical and effective mean to conduct maintenance tasks inside pipelines or conduits. If a structural crack is found on the surface of gas or fluid transport structures, more often than not the repair work would be done through excavation if these structures are situated underground. These would create considerable impact both socially and economically. As such, a robot capable of maneuvering within the internal pipe structure will be design, fabricated and assembled. The objectives for this project are identified to be: 1. Build a prototype internal pipe inspection robot (mechanical structure and locomotion mechanism). 2. Learn and cope with technologies in the field of service robot in confined space. 3. Develop a cost-effective approach in building mobile robot.

The objectives of this research program are: (a) to establish and to enhance the R&D capability in Aerospace Technology with particular reference to the turbo-fan engine exhausts. (b) to develop a forced mixer geometry that can be used for a wide range of thrust class turbo-fan engine exhausts. The specific goals of the programme are to: 1. acquire detailed fundamental fluid dynamics for the forced mixer flows 2. establish the important design criteria for the forced mixers. 3. determine the most desirable forced mixer geometry for a wide range of thrust class turbo-fan engines.

The proposed framework is intended to integrate work processes, automate the workflow with minimal human intervention, communicate with supplier through electronic data interchange (EDI) and provide a collaborative working model. Master of Science (Computer Integrated Manufacturing)

Develop a bio-mathematical model for lung ventilation for the purpose of lung disease diagnosis. Functional analysis of breathing during pulmonary dynamics, plus how lung diseases alter the properties of the lung compliance or flow resistance component of the pulmonary system. Master of Science (Biomedical Engineering)

An information deduction approach based on quality function deployment is proposed to ferive the information dependencies between design tasks and then model the information structure of a design project. Doctor of Philosophy (MPE)

97 p. In most research work done on rechargeable batteries, little investigation has been done on how the batteries perform under different kinds of load. Electrical load is basically composed of resistive, inductive and/or capacitive. In this project, an intelligent battery testing setup was designed and built with the appropriate software written to allow various batteries to be subjected to various load condition representing real world conditions. It was evident from the findings that different loads produce different energy outputs. It was concluded that the NiMH battery does not perform to specification as well as the NiCd and variations exist between the manufacturers rating and the actual output. A load with a RL, RC or RLC circuit enabled a longer battery discharge duration when compared to a purely resistive load. Further investigation suggests that a more in depth research is required to quantify the energy output contribution by the inductive and capacitive load. Master of Science (Smart Product Design)

Determine the local surface shape on the foot surface from plantar view, some scans were performed to obtain the scattered data points on the sole of foot. Two conditions of feet were scanned: weight bearing condition and non-weight bearing condition. Master of Science (Biomedical Engineering)

This dissertation seeks to study the concepts of the Request for Information (RFI), Request for Prosposal (RFP) and Request for Quotation (RFQ) processes today and the purposes and objectives behind each of these processes. Master of Science (Logistics)

Improve the operational productivity with minimal structural development mainly via redesigning of storage system and addition of facilities. Master of Science (Logistics)

This dissertation investigates the variation of the surface roughness of a single crystal CuAINi SMA at different strains, and the surface topography at a certain strain when the surface is of good pattern. It may provide a very useful guide for the design of SMA based micro optical devices. Master of Science (Precision Engineering)

From initial biomedical applications in the fields of prosthesis, implants, and surgery planning, the scope of Rapid Prototyping (RP) applications have expanded to include areas in tissue engineering (TE) and controlled drug delivery. Master of Engineering (MPE)

This project discusses the successful development of a virtual and collaborative design software, Vdesign, for information communications within a company and external sites. Vdesign is capable of facilitating designing activities, sharing fdes (2 or 3 dimensional drawings) and information as well as discuss issues over the Intranet, Extranet and Internet. Master of Science (Computer Integrated Manufacturing)

The purpose of this study was to investigate how PDA with information on potential suspects can be used to help security guards to trace and capture subjects. The study focuses on the design of the PDA display interface and the effects of landmark navigation in a familiar working environment. Master of Science (Human Factors Engineering)

Develop and validate an anatomically accurate three-dimensional FE (L2/L3) model of lumbar spine using actual human cadaver specimen for biomechanical study. Doctor of Philosophy (MPE)

Use of recent techniques from image-based rendering to bridge the gap between rendering quality and speed. It uses prefiltered high-dynamic range environment maps of the real scene, containing real lighting information, to render diffuse and glossy virtual objects with a novel multi-pass rendering framework. Master of Engineering (MPE)

Cold compaction of metal powders is widely used in the industry. The ability to produce the required shape and dimensions of a component with very little or without subsequent machining is the main advantage compared to other production processes. The manufacture of a powder compacted component may roughly be split up in two steps. First the powder is compacted to desired shape and subsequently the compact is sintered in order to weld the powder particles together and thereby attain the desired strength. Focus in the present work will be on cold die compaction where plastic deformation of the powder particles is the major deformation process. At higher temperatures, diffusion and creep start to play a role. Master of Science (Precision Engineering)

Thirteen design variations will be analysed for the solder joint reliability. The Strain Energy Density will be obtained from the studies and the solder joint fatigue life predicted. The effects of the thickness and polyimide coating layer that protects the exposed die, will also be examined for package stress level. Master of Science (Biomedical Engineering)

Improvement the thermal management by using the two miniature heat sinks mounted on the two chips. The flexible circuits are folded in a manner that the chips with and without the diamond heat sinks are stacking on each other. Master of Science (Precision Engineering)

Build and internally validate, based on deterministic and stochastic approaches, a tractable model of the interactions between various important molecules involved in the mitotic exit of budding yeast; and implement a workable hybrid method that has a simulation speed close to that of the deterministic approach but also an accuracy similar to that of the stochastic approach. Master of Science (Biomedical Engineering)

The study focuses on determining the optimum lot size for the backend factory with the objective of achieving capacity increases with minimal equipment additions. The method used in the study describes the technical methodology and investigates an optimum lot size based upon given throughput and cycle time targets. The results of this study show that a larger lot size is very much desirable in the areas of the factory that are highly utilized. Small lot sizes will increase the number of setup for the machine, which will cause reduction in the output. The study also shows that different products will have a different lot sizes requirement because the processing time of the lot size will be different. Master of Science (Logistics)

The objectives of this research are to design and develop an improved tracheobronchial stent and to devise an algorithm that allows rapid fabrication of this implant to serve customised airway requirements. This project also aims at developing a mechanical test protocol for in vitro testing of the prototype stent mechanical properties. Master of Engineering (MPE)

In this research work, a legged robot called BEETLE II is developed. Master of Engineering (MPE)

The present research has extensively investigated the properties of sputter deposited NiTi-based shape memory alloy thin films and the influencing factors. Doctor of Philosophy (MPE)

Investigation of the feasibility and benefits of cellular manufacturing as compared to conventional layout in pharmaceutical industry, and also the possibility of reducing product contamination and improving the work flow of WIP goods. Master of Science (Computer Integrated Manufacturing)

The surface interaction between the hepatic asialoglycoprotein receptor (ASGPR) and collagen molecules using molecular dynamics simulation. The interaction energies of the receptor-collagen and their complex with water were calculated using a Hyperchem molecular mechanics model. Master of Science (Biomedical Engineering)

107 p. This project works on a gripper and flipper mechanism for a Beetle robot. A robotic game has been proposed for two Beetle robots to play a ball game. The game works on a simple rule: which ever Beetle robot that can capture the ball on the court and bring it to the "home" location will win. As such the gripper mechanism is devised for the purpose of capturing the ball. The Beetle robot holding the ball will bring the ball to the "home" location. Both the Beetle robots are equipped with a flipper mechanism that can trigger each other's weak spot and result its opponent to freeze and open up the gripper (thus releasing the ball if it is holding to one). This gives the other Beetle robot an opportunity to recapture the ball. Master of Science (Smart Product Design)

The focus of this work is on a class of three-legged modular reconfigurable parallel manipulators having spherical end joints. In the study on instantaneous kinematics, easy generic and intuitive method of determine reciprocal screws based on POE scheme is proposed using twist annihilators. Doctor of Philosophy (MPE)

133 p. This project is to develop and design a Heel Pad Thickness Measuring (HPTM) device that is capable of measuring the heel pad thickness of an adult human. It was identified that such a device has potential as a diagnostic tool and could subsequently play a complementary role in foot reflexology therapy. The HPTM device utilises a hybrid technique of measurement. It combined a force displacement technique with ultrasonic imaging to measure the heel pad thickness in its compressed and uncompressed state. Master of Science (Smart Product Design)

Accurate knowledge on how the human body uses a combination of passive constraints and active controls to control joint motion during different activities is important to clinical practice. A necessary prerequisite for studying the control is a complete evaluation of the kinematics of joints. This thesis especially focuses on elucidating the kinematics of the normal ankle joint complex. The work may be divided into two general parts: experimental measurements of the kinematics and the development of an anatomy-based mathematical model to examine the effect of the individual passive constraints on determining the kinematics. Doctor of Philosophy (MPE)

An investigation of the biomechanics of lifting a wheelchair user from the wheelchair, the first stage of a chair- to-chair transfer as would be performed in bathing or toileting. Master of Science (Biomedical Engineering)

A new Hysteretic Arctangent Model was proposed to model the performance characteristics of a MR damper. The new model gives piecewise smooth characteristics for the MR damper and gives a more accurate representation of the damper characteristics comparing with the other existing models. The MR damper was then studied based on the damper model developed and applied to semiactive control of vehicle suspension system. A quarter car model was used in the computational simulation. Several control strategies - both passive and semiactive ones - were discussed and the results from simulation were evaluated for each control strategy. Master of Philosophy (MPE)

95 p. Computer numerical Control machines play a vital role in the manufacturing economy of a nation. The industrialized nations of the world have made significant progress in the area of automation in manufacturing systems, which makes them more competitive in this era of a globalized economy. Automation involves numerically controlled machines, which are mainly controlled by computers today. CNC machines are used widely to improve the manufacturing performance and also to save both time and cost. Since NC machines involve high investments, it is necessary to make them more productive to obtain a significant return on the investments. Master of Science (Computer Integrated Manufacturing)

Information technology plays an important role in the dynamic airfreight industries worldwide, as the key-enabling factor that makes operations systems, processes, and overall enterprises more agile and productive. It is important that researchers and practitioners working in areas related to this field address the ramifications of advances in both established and emerging information technologies and their impact on airfreight system development and operations. This is due to the fact that accurate information flows among the links of an organisation in a timely, coordinated fashion not only minimizes distortions but also help prevent errors in critical business processes, which tend to result in costly failures in the short run that may undermine viability in the long run. Hence, information systems must be capable of incorporating latest information of events affecting the air-cargo chain, especially in freight capacity management to prevent costly off-loading errors and at the same time permitting the business organisation to benefit from airline rebates. Master of Science (Computer Integrated Manufacturing)

174 p. Tissue Engineering (TE) is an important field in biomedical engineering that has raised interests among clinicians and engineers in the quest for alternative replacements for tissues, implants and organs. TE strategies for creating natural tissues or organs for anchoring dependent cell types rely on the application of temporary three-dimensional scaffolds to guide the proliferation. The characteristics required of TE scaffolds are major concerns in the pursuit to design and fabricate ideal scaffolds. Rapid Prototyping (RP) technologies are fast becoming the techniques of choice for the fabrication of TE scaffolds that can overcome the setbacks and limitations of conventional manual-based techniques. Master of Engineering (MPE)