A Network Technique for Analysis of the Thermal Transient Casting Process

A network approach to simulating the thermal transient casting process is presented and compared with experimental data and a continuum finite element model. For a sufficiently fine network, all comparisons are good. The approach is economical on computer effort and may be used for a first iteration in die design. The capability to model successive casting cycles is presented, which shows the die thermal history to achieve stable operatio

Mechanical Properties of Paddy Soil in Relation to High Clearance Vehicle Mobility

This study reports the mechanical properties of paddy soil in respect to vehicle mobility in Sungai Burong, Tanjung Karang, Malaysia. Soil samples were taken from the topsoil layer of 0-5 cm and subsoil layers of 5-15 cm, 15-25 cm and 25-35 cm depths at fifteen different locations in triplet replications using 216 cm3 volume core samplers. Soil shearing characteristics, parameters that include water content, bulk density, soil cohesion, angle of internal friction, shear deformation modulus were determined in the laboratory using oven and direct shear box apparatus. The loadsinkage test was carried out in field using soil bearing capacity apparatus. The mean values of paddy soil water content and bulk densities obtained were 47.08 %, 60.65 %, 79.78 %, 94.07 % and 9. 8 x 10-10 g/cm3, 1.24 x 10-9 g/cm3, 1.30 x 10-9 gc/m3, 1.45 x 10-9 g/cm3 at depths of 0-5 cm, 5-15 cm, 15-25 cm and 25-35 cm respectively. Mean values of soil cohesion, angle of internal friction and shear deformation modulus were found to be 6.22 kN/m2, 5.03 kN/m2, 3.15 kN/m2, 1.40kN/m2 and 30.73o, 27.87o, 18.22o, 17.86o at depths of 0-5 cm, 5-15 cm, 15-25 cm and 25-35 cm respectively. It was found that the in-situ shearing strength of the paddy soil dropped from 3.32 kN/m2 to 2.16 kN/m2 to 1.74 kN/m2 and to 1.59 kN/m2 as the depths increased from 0-5 cm, 5-15 cm, 15-25 cm and 25-35 cm respectively. This shows that vane blade size and depth had significant effect on the in-situ shearing strength. It was also observed that the plate sinkage in the paddy soil increased with increasing pushing loa

Effect of ultraviolet irradiation (UV-C) on quality attributes of pineapple-mango juice blend compare with thermal pasteurization

This intended paper was done to give an early overview of the expected quality attributes of pineapple-mango juice blend treated with ultraviolet irradiation (UV-C) and thermal pasteurisation. Josapine pineapple (Ananas comosus L.) and Chokanan mango (Mangifera indica L.) is the popular tropical fruits in Malaysia with unique taste and constant availability. The blend of pineapple-mango juice predicted to have good overall quality attributes as proved by prior studies on orange-pineapple, lemon-melon, pineapple-carrot-orange and carrot-apple-banana juice blends. Conventional thermal pasteurisation widely implemented in juice industry but resulted in massive quality degradation. Thus, research on the non-thermal technology of UV-C widely studied to overcome such drawbacks of thermal pasteurisation. Effect of UV-C and thermal pasteurisation on pineapple-mango juice blend will be evaluated in terms of physicochemical (pH, titratable acidity, total soluble solids, turbidity and colour), antioxidant (ascorbic acid, total phenolics content and total antioxidant DPPH assay) and microbiological properties. UV-C treated pineapple-mango juice blend believed to have better retention of heat sensitive ascorbic acid and other quality compared heat pasteurised juice with minimal distinctive characteristic compared to fresh juice

UV-C effect on microbial disinfection of pineapple-mango juice blend using Dean-vortex technology

This study intended to evaluate the effect of ultraviolet irradiation (UV-C) treatment of Dean-vortex technology on pineapple-mango juice blend microbial safety. Non-thermal alternative treatment of UV-C known to be promising in juice processing but low penetration depth in opaque liquid resulted in enhancement of treatment using dean vortex. Dean vortex promotes mixing in helically arranged treatment tube. Two pump frequency was selected (40 and 45Hz) to be performed on pineapple-mango juice blend at blending ratio of 70%pineapple and 30% mango. The flow regimes inside the polyfluoroalcoxy (PFA) tube behave as turbulence as the effect of dean vortex for both flow rates of the pump which brought the targeted microorganism closer towards light source relatively improve treatment efficiency. Pathogenic E. coli O157: H7 that can cause fatality was inoculated into pineapple-mango juice blends. This study shows that at a UV-C dosage of 8.38mJ/cm² able to reduce E. coli O157: H7 more than 5 log reduction. Although UV-C treatment unable to fully disinfect yeast and mould counts in pineapple-mango juice blend, the detection colony was still under the permissible limit (1.26 log CFU/mL). These proved that UV-C treatment with the implementation of dean-vortex technology able to meet the microbial load safety limit comparable to commercialize practice using thermal pasteurization

Preliminary study on biohydrogen production by E. coli from sago waste

Sago waste which has not been fully utilised is a potential substrate for biotechnological applications. This study is concerned with hydrogen gas production by Escherichia coli (E. coli) using dark fermentation and sago waste as the substrate. Glucose content after acid pre-treatment process for sago waste at 90°C for 40 minutes was 2.150 g/L. Inoculum size, pH and temperature were the 3 factors investigated during fermentation process. Design of experiment was performed using Central Composite Design (Design Expert v6.0.8). A maximum yield of 2.22 mol H2/ mol glucose was achieved from Run 8 at the pH of 6, temperature of 40°C and 30% inoculum size

Effects of gamma irradiation on egg hatchability, pupation, and adult emergence of the immature stages of the oriental fruit fly, Bactrocera dorsalis (hendel) (diptera: tephritidae) from Malaysia

Studies on the effect of irradiation on egg hatchability, pupation and adult emergence of the immature stages of the Oriental Fruit Fly, Bactrocera dorsalis (Hendel) was conducted in Malaysian Nuclear Agency, Dengkil, Selangor, Malaysia using a Co-60 source. Eggs, 1st instars to 3rd instars larvae and pupae stages were treated separately with dosages 50Gy to 400Gy to determine the most tolerance stage and the optimum dose for provide quarantine security. Each treatment involves a minimum of 100 individuals for each dose with four replications. The hatch from eggs to 1st instar larvae, pupation from eggs and all of three instars larvae to pupae, and eclosion from pupae to adult, were used as criteria to determine the effect of irradiation. Egg hatch was completely inhibited by 100Gy for early egg and 300Gy for late eggs. Dose of 200Gy and 250Gy were able to prevent completely pupation when treated from egg stage and 1st instar larvae, respectively. Unfortunately, those dosages did not affect pupation when applied to 2nd and 3rd instars, but it did prevent any from emerging as adults. Adult emergence was 100% prevented when eggs and all larvae were treated at 100Gy as compared to pupae was not completely prevented even by 400Gy. Among the four immature stages of B. dorsalis, the 3rd instar larvae (inside fruits) and pupae (outside fruits) were found to be the most tolerance stage and the early eggs are the most susceptible stage to irradiation. Our results suggest that minimum dose 100 to 150Gy is sufficient to provide a high level of quarantine security against this important pest and the dose might allow for irradiation be accepted as a quarantine treatment for most tropical fruits from Malaysia

Comparison of UV-C and thermal pasteurisation for the quality preservation of pineapple-mango juice blend

Massive grow in the juice industry promotes the development of the new flavour juice by blending two or more different types of fruits. Application of ultraviolet-irradiation of light spectrum C (UV-C) on single juice already widely explored whereas limited study was done on juice blend. Thus, the effect of ultraviolet-irradiation (UV-C) on physicochemical and antioxidant properties of pineapple-mango juice blend was investigated. Pineapple and mango juice blended together at blending ratio of 70 pineapple: 30 mango (volume/volume). Physicochemical properties of pH, total titratable acidity, total soluble solid and turbidity of pineapple-mango juice blends UV-C (UV-C dosage of 8.38mJ/cm²) and thermally (90°C, 5 mins) treated were significantly changes (p<0.05) during 9 weeks of storage at 4°C. Antioxidant qualities namely ascorbic acid, total phenolic compounds (TPC), and total antioxidant (as DPPH assay scavenging activities) of UV-C treated pineapple-mango juice blend shows higher values throughout the storage period. A Pearson correlation showed that ascorbic acid is the main contributor in antioxidant properties of pineapple-mango juice blend as decreased in ascorbic acid content caused degradation in TPC during storage. Present study proved that UV-C treatment better in nutritional and heat sensitive component retention compared to conventional thermal pasteurisation

Initiation Economic Information for Decision Making Process in Housing Development

Conflict communication among developer and their team at all times happened due to limited financial information. A developer does not automatically construct a unit that will convince the recipients since they have their own viewpoint and mind of their needs, objectives, obstructions, and necessities of economic aspect. A decision is very hard to be made on the housing unit since the recipients have variance on numerous economic issues. This paper aims to identify the economic decision making information for housing development at the initiation phase in Malaysia. Delphi method is implemented in 3 rounds using a questionnaire survey which involved 34 private developers for data collection purposes. The finding shows that authority policies, a market of housing and timing (life cycle of a project) are most necessary information in the economic part. All of the economic information also illustrates that they are crucial and key factors in the decision-making process. The stages in the initiation phase require economic information in the form of a qualitative data bank of a developer

Effect of storage on physicochemical properties and microbiological stability of osmodehydrated pineapple (Ananas comosus) treated with sucrosesorbitol mixtures

Osmotic dehydration (OD) is an effective fruits preservation technique with minimal nutrients loss. The study aimed to determine physicochemical properties and microbial stability of osmodehydrated pineapple. The experiment were conducted using 65 °Brix sucrose-sorbitol mixtures (100:0, 0:100 and 25:75) at 40 °C for 240 minutes OD and continued for hot air drying to 20% moisture content at 50 °C. Samples were vacuum-packed and stored at 4 °C. Textural, physicochemical properties (moisture content, aw), flavonoids, vitamin C and microbial stability were determined. Results showed that samples treated with sucrose-sorbitol mixtures (0:100 and 25:75) able to extend the shelf life of pineapple up to 35 days and 49 days at bacteria count ≤106 CFU/g and yeast and mould ≤104 CFU/g, respectively. While, sucrose (100:0) treated pineapples only able extend the shelf life up to 14 days. In conclusion, reducing water activity of sorbitol able to extend the shelf life of osmodehydrated pineapple

Process parameters for cylindrical deep drawing components

Sheet metal forming is one of the most important manufacturing processes in today’s industries, either to produce semi-finished or finished products. The demand for rapid, low-cost die fabrication and modification technology is greater than ever in sheet metal forming industry. Therefore, a great need for the development of both theoretical and experimental engineering methods which enables the problems to be tackled effectively; this is necessary to reduce production cost and to reduce the lead time between design and production. Due to recent development in numerical method technology, finite-element analysis has become one of the important tools in predicting the result of product deformation. With the intention to study the product failure which is the thinning effect, an experimental method has been developed to monitor the metal flow behaviour during the process. With this experiment, the actual product has been drawn with different draw depths, punch and die corner radii on mild steel and aluminium materials. Finally, the product wall thickness and diameter have been measured and data gained were interpreted into graph to visualise the influences of the process parameters such as draw depth, punch and die corner radius on the thinning effect. The results would give tool maker and tool designer guidance for selecting the best punch and die radius size in order to minimise the thinning effect on the drawn product