Seberang Perai Research Articles

Monsoonal differences and probability distribution of PM10 concentration

There are many factors that influence PM(10) concentration in the atmosphere. This paper will look at the PM(10) concentration in relation with the wet season (north east monsoon) and dry season (south west monsoon) in Seberang Perai, Malaysia from the year 2000 to 2004. It is expected that PM(10) will reach the peak during south west monsoon as the weather during this season becomes dry and this study has proved that the highest PM(10) concentrations in 2000 to 2004 were recorded in this monsoon. Two probability distributions using Weibull and lognormal were used to model the PM(10) concentration. The best model used for prediction was selected based on performance indicators. Lognormal distribution represents the data better than Weibull distribution model for 2000, 2001, and 2002. However, for 2003 and 2004, Weibull distribution represents better than the lognormal distribution. The proposed distributions were successfully used for estimation of exceedences and predicting the return periods of the sequence year.

Institutional Policies and their Implications on Land Use Change and the Environment: Lessons Learned from Seberang Perai, Penang, Malaysia

Institutional Policies and their Implications on Land Use Change and the Environment: Lessons Learned from Seberang Perai, Penang, Malaysia

Characterizing the scale sensitivity of the cellular automata simulated urban growth: A case study of the Seberang Perai Region, Penang State, Malaysia

In modeling the complex behaviour of urban systems using a cellular automata approach, scale is an important concept in representing space since the result obtained at specific scale shall not be expected to be valid at another scale. The selection of scale, however, has often been taken for granted on the basis of information available to be mapped. Although it is desirable to run a model with fine spatial scale datasets, such datasets may well be costly to collect and add computational expenses in processing. This article investigates the effect of changing scale on the performance of a GIS-based cellular automata (CA) model developed to simulate the spatial pattern of urban growth. The sensitivity of scale of the input data used to parameterize the model was undertaken by evaluating the resulting prediction accuracy of the model and the morphology of urban areas. It seemed that the model managed to perform well and produce realistic urban form only up to specific range of scale. Thus, the selection of scale to represent urban system under consideration has to be undertaken with care, in order to ensure that the output produced maintains the overall accuracy of the model and morphology of urban areas.

Factors associated with depression among elderly patients in a primary health care clinic in Malaysia

Aim: To identify the factors associated with depression among elderly patients attending a primary health care clinic in Malaysia. Methods: A cross sectional study was conducted on patients aged 60 years and above in Klinik Kesihatan Butterworth, Seberang Perai Utara, Pulau Pinang, Malaysia from April to September 1999. The Geriatric Depression Scale questionnaire was used as a screening instrument. Results: The response rate was 99.0%. A total of 18% of the patients were found to have depression. The associated factors were females (odds ratio (OR) = 2.87, 95% confidence interval (CI) = 1.37‐6.02), those who were unmarried (OR = 3.46, 95% CI = 1.66‐7.21), without formal education (OR = 8.0, 95% CI = 2.97‐21.48), low total family income (OR = 7.97, 95% CI = 2.71‐23.46) and urban residence (OR = 2.23, 95% CI = 1.09‐4.58). Conclusion: Depression is very common among the elderly. As this is an important problem in primary care practice, primary care doctors should be aware of this problem so that early detection and management can be implemented. © 2003 Blackwell Publishing Asia and Wonca

THE GENUS MIMOSA WITH SPECIAL REFERENCE TOM. QUADRIVALVIS L. VAR. LEPTOCARPA (D.C.) EARNEDY, A NEW SPECIES RECORD FOR THE WEED FLORA IN MALAYSIA*)

An exploratory floristic survey of the genus Mimosa was conducted in 1993 to ascertain species diversity and their spatial patterns of distribution in Peninsular Malaysia. A new species record of uncertain indigene, M.. quadrivalvis was recorded for the first time in restricted localities along the roadsides in Pekan Darat and Bertam, Seberang Perai, Gurun and Bedong in Kedah in addition to widely distributed and seemingly ubiquitous presence of M. invisa Mart. ex. Colla and M. pudica L. The latter two species were mostly found in open, disturbed and derelict habitats, agricultural areas and ex-mining lands. Both species exhibited largely contagious and overdispersed distribution patterns with positive peaks in pattern intensity values although regularity or underdispersed distribution patterns do manifest in certain localities. The giant mimosa, M. pigra inhabited in clustered thickets, large pockets of lands in the urban and sub-urban localities in the states of Penang, Perak, Kelantan, Kuala Lumpur and Negeri Sembilan. In other states, M. pigra was confined to a few localities in smaller patches. Except for M. quadrivalvis, the other species of Mimosa are serious weeds in the agricultural, recreational and residential and derelict areas. A key to the Mimosa species is constructed along with brief descriptions on their morphology and ecology. Key words: Malaysia/Weed ecology/Mimosa invisa/Mimosa pigra/Mimosa pudica/Mimosa quadrivalvis/ Weeddistribution/Weed anatomy and morphology.