University of Malaya

About: University of Malaya is a education organization based out in Kuala Lumpur, Malaysia. It is known for research contribution in the topics: Population & Fiber laser. The organization has 25087 authors who have published 51491 publications receiving 1036791 citations. The organization is also known as: UM & Universiti Malaya.

The impacts of transport energy consumption, foreign direct investment and income on CO2 emissions in ASEAN-5 economies

Abstract: In this study, we incorporate new variables and assess the impact of transportation sector's energy consumption and foreign direct investment on CO2 emissions for ASEAN-5 economies using the cointegration and Granger causality methods. This study also attempts to validate the Environmental Kuznets Curve (EKC) hypothesis. Our results reveal that the CO2 emissions and their determinants are co-integrated only in Indonesia, Malaysia and Thailand. The long-run elasticity estimation suggests that income and transport energy consumption significantly influence CO2 emissions whereas FDI is not significant. Economic growth plays a greater role in contributing to CO2 emission in ASEAN-5. Nonetheless, we find that the inverted U-shape EKC hypothesis is not applicable to the ASEAN-5 economies, especially in Indonesia, Malaysia and Thailand. In the long run, the bi-directional causality between economic growth and CO2 emissions is detected in Indonesia and Thailand, while we find unidirectional causality running from GDP to CO2 emissions in Malaysia. We also observe bi-directional causality between transport energy consumption, FDI and CO2 emissions in Thailand and Malaysia. As an immediate policy option, controlling energy consumption in transportation sector may result in a significant reduction in CO2 emissions. However, this may slow the process of economic growth in Malaysia and Indonesia. Alternatively, we suggest policymakers to place more emphasis on energy efficient transportation system and policies to minimise fossil fuel consumption. Thus, the quality of environment can be improved with less deleterious impact on economic growth.

Focus group discussion: a tool for health and medical research.

Abstract: Focus group discussion is a research methodology in which a small group of participants gather to discuss a specified topic or an issue to generate data. The main characteristic of a focus group is the interaction between the moderator and the group, as well as the interaction between group members. The objective is to give the researcher an understanding of the participants' perspective on the topic in discussion. Focus groups are rapidly gaining popularity in health and medical research. This paper presents a general introduction of the use of focus groups as a research tool within the context of health research, with the intention of promoting its use among researchers in healthcare. A detailed methodology for the conduct of focus groups and analysis of focus group data are discussed. The potentials and limitations of this qualitative research technique are also highlighted.

Loss of muscle strength, mass (sarcopenia), and quality (specific force) and its relationship with functional limitation and physical disability: the Concord Health and Ageing in Men Project.

Abstract: OBJECTIVES: To determine the association between loss of muscle strength, mass, and quality and functional limitation and physical disability in older men. DESIGN: Cross-sectional study of older men participating in the Concord Health and Ageing in Men Project (CHAMP). SETTING: Elderly men living in a defined geographical region in Sydney, Australia. PARTICIPANTS: One thousand seven hundred five community-dwelling men aged 70 and older who participated in the baseline assessments of CHAMP. MEASUREMENTS: Upper and lower extremity strength were measured using dynamometers for grip and quadriceps strength. Appendicular skeletal lean mass was assessed using dual X-ray absorptiometry. Muscle quality was defined as the ratio of strength to mass in upper and lower extremities. For each parameter, subjects in the lowest 20% of the distribution were defined as below normal. Functional limitation was assessed according to self-report and objective lower extremity performance measures. Physical disability was measured according to self-report questionnaire. RESULTS: After adjusting for important confounders, the prevalence ratio (PR) for poor quadriceps strength and self-reported functional limitation was 1.91 (95% confidence interval (CI) 51.10-2.40); for performance-based functional limitation the PR was 1.81 (95% CI = 1.45-2.24). The adjusted PR for poor grip strength and physical disability in instrumental activities of daily living (IADLs) was 1.37 (95% CI = 1.20-1.56). The adjusted PR for low skeletal lean mass (adjusted for fat mass) and physical disability in basic activities of daily living was 2.08 (95% CI = 1.37-3.15). For muscle quality, the PR for lower extremity specific force and functional limitation and physical disability was stronger than upper extremity specific force. CONCLUSION: Muscle strength is the single best measure of age-related muscle change and is associated with physical disability in IADLs and functional limitation. J Am Geriatr Soc 58:2055-2062, 2010.

Single-Phase Seven-Level Grid-Connected Inverter for Photovoltaic System

Abstract: This paper proposes a single-phase seven-level inverter for grid-connected photovoltaic systems, with a novel pulsewidth-modulated (PWM) control scheme. Three reference signals that are identical to each other with an offset that is equivalent to the amplitude of the triangular carrier signal were used to generate the PWM signals. The inverter is capable of producing seven levels of output-voltage levels (Vdc, 2Vdc/3, Vdc/3, 0, -Vdc, -2Vdc/3, -Vdc/3) from the dc supply voltage. A digital proportional-integral current-control algorithm was implemented in a TMS320F2812 DSP to keep the current injected into the grid sinusoidal. The proposed system was verified through simulation and implemented in a prototype.