Cryogenic, high power, near diffraction limited, Yb:YAG slab laser

A cryogenic slab laser that is suitable for scaling to high power, while taking full advantage of the improved thermo-optical and thermo-mechanical properties of Yb:YAG at cryogenic temperatures is described. The laser uses a conduction cooled, end pumped, zigzag slab geometry resulting in a near diffraction limited, robust, power scalable design. The design and the initial characterization of the laser up to 200W are presented.Miftar Ganija, David Ottaway, Peter Veitch and Jesper Munc

Talus Features of the Middle Columbia River: Typological and Locational Analyses

The form and function of talus features of the Columbia Plateau are the subject of archaeological investigations and cultural resource evaluation and protection programs. Depressions excavated in talus slopes, most often circular to oval in shape, are called talus pits. Pit features are also located in colluvium and alluvial fans, and at the base of cliff overhangs. Over 568 of these features have been documented for 48 sites within the project area of the Priest Rapids and Wanapum reservoirs. Pits may have been used for hunting blinds, storage (food and/or equipment), burial, and/or and spirit questing. The size of pits and the frequency of pits per site, combined with historic associations with human remains, suggest that most talus pit sites are cemeteries. Pits and pit sites are found in higher than expected frequencies on the west side of the Columbia River and on northeast and southeast facing slopes. The distribution of pits by river mile for the east and west sides of the river do not correspond to changes in the elevation of the river (rapids) or the amount of talus slopes or alluvial fans. The location of house features and house sites are compared to the distribution of talus pits by average distance and by river section. There is only partial correspondence of house sites and talus site locations. The number of houses and number of talus pit features, and reported location of ethnohistoric settlements, are not well correlated. Some talus pits and house features are found in the middle stretch of the project (Vantage-Rocky Coulee). However, overall, talus features, house features, and historic settlement locations concentrate on the upper (Colockum Creek-Cabinet Rapids) and lower (Priest Rapids) ends of the project area. This distributional pattern best fits the interpretation that sites with large number of pits are cemeteries associated with separate communities

Effects of ultrasonic waves on enhancement of relative volatilities in methanol-water mixtures

The application of ultrasonic wave in various fields including separation process has increased predominantly. This paper reports the practicability of using ultrasonic wave to enhance separation of binary mixtures by distillation. The binary mixture utilized was methanol-water. The effect of different ultrasonic intensity at 50, 100, 200 and 250 W/A.cm2 with frequency of 40 kHz to vapor-liquid equilibrium (VLE) of methanol-water was investigated to obtain the most suitable operating intensity. Experimental studies were also carried out to investigate the frequency effect (25 and 68 kHz) to VLE data. It was found that the use of ultrasonic wave enhanced the separation process by increasing the relative volatility of components. The highest average relative volatility of methanol-water at 29.413 was obtained from experimental study using intensity 200 W/A.cm2 and frequency of 25 kHz. The changes in relative volatility and VLE were caused by cavitational activities and vacuum effect that occur during transmission of ultrasonic wave in liquid medium. The results from this study proved the practical feasibility of using ultrasonic wave to enhance separation of binary mixtures in distillation column

The development of an intelligent system for the design evaluation and improvement of manufacturability and assembly of product.

Assembly is one of the most important stages of product development. Design for Manufacturing and assembly (DFMA) is one of the approaches to improve the product designs for easier and least assembly cost with high functionality of the products

Risk and Return of the KLSE Finance Stocks and the Performance of Banking Stocks in Malaysia

The purpose of this study is to investigate the relationship between risk and return of fifty Finance Stocks listed on the Main Board of Kuala lumpur Stock Exchange for the period of 30th May 1995 to 30th May 1997. In addition to this objective, the performance of Big Five local Banks in relations to the KlSE FinanCe Index is also analyzed using the Performance Measurement Indices of Sharpe, Treynor and Jensen. The study found that during the above period, the Maybank stock is the least riskiest finance stocks in the top Five local Banks. For other finance stocks, Phileo Allied Berhad is the riskiest security while Bank Islam Malaysia Berhad is least riskiest. The return for Finance Stocks is 60% more than the return on the Composite Index as reflected by the Beta Coefficient. Finance Stocks have high positive correlations relative to the Composite Index. The study has also corraborates the hypothesis that the return of securities with high betas to be greater than the returns of the securities with low betas, consistent with risk-return theoretical relationship

Geospatial and multivariate statistical analysis of heavy metal concentration in soils of Perlis / Siti Norbaya Mat Ripin

Urbanisation and industrialization have elicited continuous emission of metals which pose a great threat on human health. Soil samples from 19 station (include control) in Perlis obtained in triplicates and at depths of 0 to 15, 15 to 30, 30 to 45, 45 to 60, 60 to 75 and 75 to 90cm. 7 metals (Pb, Cu, Zn, Cr, Co, Ni and As) was analysed using microwave digestion to determine the concentration and distribution of heavy metals in soil of Perlis. The results with Pb (12.6), Cu (13.8), Zn (157.9), Cr (94.9), Co (3.4), Ni (197.7) and As (19.6) mg/kg exceed the control values. As compared with allowable limit set for soils from the Department of Environment and World Average Soil Value, Pb, Zn, Cr, Ni, As relatively higher. This indicates that the anthropogenic activities and reaction between soil properties and metal affected the soils in the study area greatly. Most soil samples high in surface soil (0-15cm) and decrease from first depth to third and increase from third depth to sixth depth. The mobility of heavy metals largely depended on the role of soil properties such as organic matter, clay content, nodules formulation of Fe and Mn oxides, metal properties and concentration. Implementation of geostatistical and multivariate analysis successfully grouped metals according to their anthropogenic or natural origin and illustrate the spatial distribution trends confirming the clear contribution of anthropogenic inputs. The results demonstrate that groups Pb, Zn and Co probably deposited by vehicular emission. Meanwhile, Cr, Cu, Ni and As were impacted by mixed sources (anthropic and natural origin). Geoaccumulation index and enrichment factor results moderate contaminated to extreme contaminated for Zn, Cr and Ni, while pollution load index has resulted a moderate pollution in station 3, 5, 6, 7, 12, 13 and 18. Findings of this study will create awareness and offer undertaking appropriate action to protect soil quality

Enhancing Design for Aesthetics Based on Product Platform Architecture

Traditionally, most people buy a product based on performance and cost, but recently appearances, comfort and aesthetic are preferred. Customers are now becoming more complex and require not only good product performance but also appearance. To enhance product appearance, product platform has been proposed as new approach to the design for aesthetics. In this work, a platform is identified based on component sharing among the product variants. Then the aesthetic rules are applied to the platform. A Product Family Aesthetic Index (PFAI) was developed to measure the product performance. The evaluation is based on component commonality and aesthetic aspect. The result indicates that the Product Family Aesthetic Index had increased through redesigning several components in the product. A case study of the fan family was conducted to verify the methodology

Transient analysis of drum brake squeal with binary flutter and negative friction-velocity instability mechanisms

A two degree-of-freedom model of a drum brake system is developed to investigate the criteria for unstable condition under friction-induced vibration instability mechanisms of both flutter instability and negative friction-velocity instability. This model considers the drum as the main component that is subjected to the friction-induced vibration. The influences of the friction coefficient, normal load, sliding velocity, contact stiffness, damping coefficient and the location of centre of pressure on the shoes on the instability of the system are investigated using transient analysis. The results indicate that the minimal model displays all the characteristics of the unstable system comparable to the previously published experimental and finite element modeling results