No abstract

No abstract

No abstract

Kertas kerja ini mempersembahkan keputusan satu kajian ergonomik berkaitan kesan kebisingan terhadap pekerja industri di Malaysia. Tiga industri berbeza yang telah dipilih untuk kajian ialah pengeluar produk berasaskan getah, syarikat hentakan logam dan syarikat percetakan penerbitan. Satu soal selidik yang mengandungi 37 soalan yang merangkumi semua aduan berkaitan kesan kebisingan terhadap manusia telah disedia dan diberikan kepada 120 pekerja industri yang dipilih. Maklum balas daripada pekerja dikumpulkan sebagai data untuk analisis selanjutnya. Satu pengujian Chi–Square telah digunakan untuk menentukan sama ada kesan kebisingan adalah signifikan atau tidak signifikan. Didapati bahawa pada tahap signifikan, α = 0.05, fisiologi, kehilangan pendengaran, audiotori dan gangguan tidur adalah kesan kebisingan yang secara statistiknya signifikan. Bagaimanapun, kesan kebisingan terhadap psikologi telah didapati tidak signifikan. Kata kunci: Ergonomik, kesan kebisingan, kesan fisiologi, kesan kehilangan pendengaran, kesan audiotori, kesan psikologi This paper presents results of an ergonomic study pertaining to the effect of noise on industrial workers in Malaysia. Three different industries selected for the study were rubber product manufacturing, metal stamping, publication and printing. A questionnaire consisting of 37 questions, covering all possible reported effects of noise on humans, was prepared and served to a total of 120 workers at the above mentioned industries. Responses from the workers were collected for analysis. A Chi–Square test was used to determine whether the effects of noise were statistically significant or not. It is found from the results of the survey, at a level of significance, α = 0.05, physiological, hearing loss, auditory, and sleep disturbances effects of noise are statistically significant. However, psychological effect of noise is found to be non-significant. Key words: Ergonomics, noise effects, physiological effects, hearing loss effects, auditory effects, psychological effects

BACKGROUND: The left coronary artery commonly known as LCA gets divided into two branches, such as the left circumflex (LCX) and left anterior descending (LAD) at a particular angle. This angle is varies from person to person. The present computational study contributes remarkable expertise about the influence of this angle variation on the hemodynamic parameters in the presence of 80% area stenosis at the LAD branch. OBJECTIVE: This study aimed to compare the effect of the bifurcation angle on hemodynamic parameters in the left coronary artery with 80% stenosis. METHOD: Computational models of left coronary bifurcation angles of 30°, 60°, 90°, 120° were developed to understand the flow behavior of left coronary artery branches. The 80% area stenosis (AS) is considered at the LAD branch immediate to bifurcation. RESULTS: Measurements of pressure, velocity and wall shear stress were carried out corresponding to various bifurcation angles. It was found that the drop-in pressure increases as the angle increases from narrow to wider. A slight elevation in the velocity at the stenosis was observed. In addition, the obtained results further reveal a recirculation region immediately after the plaque, which leads to more deposition of plaque in the flow obstructed area. It is known that the shear stress at the arterial wall across the stenosis increases as the angle of bifurcation increases from narrow to wider. CONCLUSIONS: The bifurcation of the left coronary artery and size of the stenosis have a notable impact on the pressure and wall shear stress. These two factors should be given due consideration by cardiologists to assess the complexity of stenosis in the LCA branches.

No abstract

No abstract

No abstract