A theoretical and experimental investigation into the development of coverage in shot peening

Shot peening is a mechanical surface treatment process used mainly for the improvement of the fatigue structural integrity of metallic components. In this process, the surface of a part is bombarded with small spherical media called shot, at high velocity, to induce desirable residual compressive stresses and strains within the surface layers of the component The effectiveness of the shot peemng process 1s dependent upon the uniformity of the induced compressive residual stresses and the energy transfer that occurs during the impact of the shots with the target surface. In practice, the process efficiency is established by means of coverage, intensity and saturation. Therefore, the scope of this study is to investigate the development of coverage and its relationship to intensity and saturation of peening. Within the scope, the objectives of the study are to compare and contrast the coverage results obtained experimentally with theoretical models, to establish a relationship between coverage and intensity and to obtain an empirical relationship to predict coverage. Theoretical models used to predict coverage give mixed results compared to experimental results. The Holdgate model gives a very good coverage prediction whereas the A vrami equation does not Coverage development is found to be a function of shot size, impingement angle and target material properties. Intensity and saturation time is found to be dependent upon shot size and impingement angle. Complete coverage is achieved earlier than the saturation point which 1s a contrast to the usual assumption that coverage and saturation occurs at the same time. However, a clear relationship could not be established. An empirical relationship can be used to predict coverage. This relationship, which is a function of the process parameters such as shot size and impingement angle, is established by using multiple regression analysis

Adaptive-Fuzzy Controller Based Shunt Active Filter for Power Line Conditioners

This paper presents a novel Fuzzy Logic Controller (FLC) in conjunction with Phase Locked Loop (PLL) based shunt active filter for Power Line Conditioners (PLCs) to improve the power quality in the distribution system. The active filter is implemented with current controlled Voltage Source Inverter (VSI) for compensating current harmonics and reactive power at the point of common coupling. The VSI gate control switching pulses are derived from proposed Adaptive-Fuzzy-Hysteresis Current Controller (HCC) and this method calculates the hysteresis bandwidth effectively using fuzzy logic.  The bandwidth can be adjusted based on compensation current variation, which is used to optimize the required switching frequency and improves active filter substantially. These shunt active power filter system is investigated and verified under steady and transient-state with non-linear load conditions. This shunt active filter is in compliance with IEEE 519 and IEC 61000-3 recommended harmonic standards

Environmental risk evaluation of a sanitary landfill using life cycle analysis approach / Farah Ayuni Shafie, Dasimah Omar and Subramaniam Karuppanan.

An Environmental Impact Assessment (EIA) auditing was carried out at a sanitary landfill in Kuala Langat, Selangor, Malaysia. It was conducted to assess the environmental and health impact of the landfill. The study also includes an environmental risk index and life cycle analysis (LCA) approach to evaluate the facility. The auditing arrives with a conclusion that this facility might pose a hazard to the environment and health if no adequate control measures are taken consistently. Environmental auditing and LCA simulation could become an essential tool in the monitoring of urban planning and development

Examining the Characteristics of Heterogeneous Traffic at Various Lane Closures

The primary aim of this study is to support the policy decisions on selection of a work zone layout that would have least deterrence to the traffic flow on busy urban arterials carrying heterogeneous traffic. The traffic flow characteristics were recorded with two cameras and the speed variation was obtained by plying probe vehicles fitted with Global Positioning Systems (GPSs) repeatedly in the section. The traffic stream speed and capacity of the various types of work zone sections were analyzed and it is found that near side lane closure has a relatively least effect on capacity (15 %) whereas the effect of run around type closure is maximum (46 %). The reasons for the variations in speed and capacity at these types of work zones were examined and reported. Besides, the application of the study results with respect to planning of work zone layout is discussed

Numerical analysis of low-velocity impact of carbon-basalt/epoxy hybrid laminates

349-355In this paper, an attempt has been made to numerically investigate the transient dynamic response of carbon-basalt/epoxy laminated composites subjected to low velocity impact. Carbon laminates are expensive hence, inclusion of cheaper basalt to obtain an improved, yet economical laminate is necessary. Finite element analysis (FEA) technique has been employed to simulate the laminated models. Loading profiles and test conditions from drop-weight tests have been obtained from literatures and necessary validation of FEA has also been performed. A correlation between impactor mass and velocity on the maximum laminate centre deflection has been established. In addition, the influence of hybrid stacking sequence and carbon position in the hybrid on laminate damage response has been studied. It has been observed from the study that hybrid 3 (H3) with stacking sequence CCBC-2 (best combination) showed the least deflection of all the stacking sequence sets and has the lowest deflection in all the low velocity impact testing conditions

Behaviour of hybrid fibre reinforced concrete-filled steel tubular beams and columns

This paper presents the flexural performance of newly developed hybrid fiber reinforced concrete-filled steel tubular sections. The test parametres are fiber volume fraction and fiber hybridation ratio. Initially mechanical properties studied for 10 mono fiber reinforced concrete mixes using steel and Polypropylene fibres with 0.5%, 1.0%, 1.5%, 2.0% and 2.5% volume fraction. Based on the performance optimum fiber dosage was determined in each fiber, with the same volume fraction three different fiber hybridation was developed. Developed hybrid fiber reinforcement concrete, conventional concrete and optimum mono fiber reinforced concrete was used in the concrete-filled steel tubular beams and columns to determine the structural performance. The test results shows that, fiber reinforced concrete-filled steel tubular beams display significant improvement in the flexural performance.  Keywords: CFST, hybrid, fiber reinforcement concrete, flexural behavior, moment-curvature

Off-Axis and On-Axis Performance of Novel Acrylic Thermoplastic (Elium®) 3D Fibre-Reinforced Composites under Flexure Load

The flexure response of novel thermoplastic (Elium®) 3D fibre-reinforced composites (FRC) was evaluated and compared with a conventional thermoset (Epolam®)-based 3D-FRC. Ten different types of sample 3D-FRC were prepared by varying fibre orientations, i.e., 0°, 30°, 45°, 60° and 90°, and resin system, i.e., thermoplastic and thermoset. The bending characteristics and failure mechanisms were determined by conducting a three-point bend test. Results elucidate that The flexure response of novel thermoplastic (Elium®) 3D fibre-reinforced composites (FRC) was evaluated and compared with a conventional thermoset (Epolam®)-based 3D-FRC. Ten different types of sample 3D-FRC were prepared by varying fibre orientations, i.e., 0°, 30°, 45°, 60° and 90°, and resin system, i.e., thermoplastic and thermoset. The bending characteristics and failure mechanisms were determined by conducting a three-point bend test. Results elucidate that the on-axis specimens show linear response and brittle failure; in contrast, the off-axis specimens depicted highly The flexure response of novel thermoplastic (Elium®) 3D fibre-reinforced composites (FRC) was evaluated and compared with a conventional thermoset (Epolam®)-based 3D-FRC. Ten different types of sample 3D-FRC were prepared by varying fibre orientations, i.e., 0°, 30°, 45°, 60° and 90°, and resin system, i.e., thermoplastic and thermoset. The bending characteristics and failure mechanisms were determined by conducting a three-point bend test. Results elucidate that the on-axis specimens show linear response and brittle failure; in contrast, the off-axis specimens depicted highly nonlinear response and ductile failure. The thermoplastic on-axis specimen exhibited almost similar flexure strength; in comparison, the off-axis specimens show ~17% lower flexure strength compared to thermoset 3D-FRC. Thermoplastic 3D-FRC shows ~40% higher energy absorption, ~23% lower flexure modulus and ~27% higher flexure strains as compared to its thermoset counterpart

Expression, Purification, and Biophysical Characterization of a Secreted Anthrax Decoy Fusion Protein in Nicotiana benthamiana.

Anthrax toxin receptor-mediated drug development for blocking anthrax toxin action has received much attention in recent decades. In this study, we produced a secreted anthrax decoy fusion protein comprised of a portion of the human capillary morphogenesis gene-2 (CMG2) protein fused via a linker to the fragment crystallizable (Fc) domain of human immunoglobulin G1 in Nicotiana benthamiana plants using a transient expression system. Using the Cauliflower Mosaic Virus (CaMV) 35S promoter and co-expression with the p19 gene silencing suppressor, we were able to achieve a high level of recombinant CMG2-Fc-Apo (rCMG2-Fc-Apo) protein accumulation. Production kinetics were observed up to eight days post-infiltration, and maximum production of 826 mg/kg fresh leaf weight was observed on day six. Protein A affinity chromatography purification of the rCMG2-Fc-Apo protein from whole leaf extract and apoplast wash fluid showed the homodimeric form under non-reducing gel electrophoresis and mass spectrometry analysis confirmed the molecular integrity of the secreted protein. The N-glycosylation pattern of purified rCMG2-Fc-Apo protein was analysed; the major portion of N-glycans consists of complex type structures in both protein samples. The most abundant (>50%) N-glycan structure was GlcNAc₂(Xyl)Man₃(Fuc)GlcNAc₂ in rCMG2-Fc-Apo recovered from whole leaf extract and apoplast wash fluid. High mannose N-glycan structures were not detected in the apoplast wash fluid preparation, which confirmed the protein secretion. Altogether, these findings demonstrate that high-level production of rCMG2-Fc-Apo can be achieved by transient production in Nicotiana benthamiana plants with apoplast targeting

Modification at Lattice Scale for an Optimized Optical Response of Alx(ZnO)1-x Nanostructures

We report the systematic changes of nano-scaled featur es and optical properties in a promising transparent oxide material, namely, Al x (x = 0, 1, 2 and 5%) doped ZnO 1-x (AZO). Electron microscopy investigations revealed the alterations at lattice scale depending on th e presence of Al-content in ZnO nanostructures. Lat- tice spacings of 0.26 and 0.28 nm oriented along the (0002) and (10 1 0) planes, respectively, were attributed to euhedral-and facetted-structures of hexagonal-ZnO. Th e AZO samples were furthe r characterized by XRD, SEM, UV-vis spectrophotometry, Raman spectroscopy and photoluminescence studies. It has been shown that at a dopant concentration of 2% Al in ZnO, an optimal balance could be achieved between microstruc- ture and optical properties