Several new concepts are used to describe contraceptive use histories for nearly 1200 women in Peninsular Malaysia. These histories are summarized by 81 episode histories. Transition matrices provide useful summaries of the changes women make in their contraceptive practice from one pregnancy interval to the next. Data from the mid-1940s to mid-1970s, during which period there was a dramatic increase in contraceptive use, reveal considerable inertia in individual couples' contraceptive practice. Persistence with a method was greater the less effective the method: while 86% of couples using no method in one interval used no method in the next, only 56% of couples using the pill in one interval also used it in the next. Virtually all transitions are of three types: continuation with the same method, a change from no method to some method, or a change from some method to no method. For only 1% of all pregnancies did couples use one contraceptive method before a pregnancy and a different method after the pregnancy. Differences are examined by calendar year and education.
Due to the increasingly documented prevalence of diarrhoeal diseases in Malaysia, a number of water-related programmes have been implemented in an attempt to improve health status through the reduction of incidence of waterborne communicable diseases associated with poor public water supplies. The implicit assumption underlying these projects is that the enhancement of the physical infrastructure, and subsequent improvements in the quality of the water supply, will substantially reduce water-related disease. The present study questions this hypothesis and uses a socio-ecological model as a framework to assess risk factors associated with the increased probability of waterborne disease. Research is centred on Port Dickson, a district which typifies existing water and sanitation conditions in much of semi-rural Malaysia. Health services utilization data and a 268-household diarrhoeal morbidity survey were used to measure the burden of illness of waterborne disease within the district and to identify predictors of morbidity. It was concluded that although treatment facilities will reduce the health burden in the region, a number of behavioural and sanitation factors may be more important and could act to minimize the potential impacts of improved water quality.
In Peninsular Malaysia child mortality rates (5q0) vary from 13 to 63 per thousand at district level. The spatial pattern is closely associated with the regional distribution of socio-economic factors. But due to multicollinearity it is difficult to isolate the influence of socio-economic variables from other variables by employing aggregated data. However, individual data collected in a case-control-study that was conducted in Perlis and Kuala Terengganu confirm the important role of socio-economic factors. So it should be possible to achieve a further reduction of child mortality by raising the income and educational level of the under-privileged groups. Apart from that, as the case of Perlis shows, the provision of family planning and preventive medical services may also contribute to lower child mortality independent from socio-economic changes. But, as the comparison with Kuala Terengganu shows, the utilization of family planning and preventive medical services is not only influenced by the accessibility to, but also by the socio-culturally determined acceptability of such services.
WHO recommends that 70% of dogs in a population should be immunized to eliminate or prevent outbreaks of rabies. This critical percentage (pc) has been established empirically from observations on the relationship between vaccination coverage and rabies incidence in dog populations around the world. Here, by contrast, we estimate pc by using epidemic theory, together with data available from four outbreaks in urban and rural areas of the USA, Mexico, Malaysia and Indonesia. From the rate of increase of cases at the beginning of these epidemics, we obtain estimates of the basic case reproduction number of infection, R0, in the range 1.62-2.33, implying that pc lies between 39% and 57%. The errors attached to these estimates of pc suggest that the recommended coverage of 70% would prevent a major outbreak of rabies on no fewer than 96.5% of occasions.
Preliminary analysis of the short-term impact of a running headlights intervention revealed that there has been a significant drop in conspicuity-related motorcycle accidents in the pilot areas, Seremban and Shah Alam, Malaysia. This paper attempts to look in more detail at conspicuity-related accidents involving motorcycles. The aim of the analysis was to establish a statistical model to describe the relationship between the frequency of conspicuity-related motorcycle accidents and a range of explanatory variables so that new insights can be obtained into the effects of introducing a running headlight campaign and regulation. The exogenous variables in this analysis include the influence of time trends, changes in the recording and analysis system, the effect of fasting activities during Ramadhan and the "Balik Kampong" culture, a seasonal cultural-religious holiday activity unique to Malaysia. The model developed revealed that the running headlight intervention reduced the conspicuity-related motorcycle accidents by about 29%. It is concluded that the intervention has been successful in improving conspicuity-related motorcycle accidents in Malaysia.
A study on lead exposure among school children aged between 7 and 12 years from Kajang and Sepang in the state of Selangor, Malaysia was carried out using delta-aminolevulinic acid (delta-ALA) levels in the urine as an index. The delta-ALA levels in urine were linked to variables which could contribute to lead exposure. Out of 1628 school children studied [Kajang (43.5%) and Sepang (56.5%)], only 194 subjects (16 and 8.8% from Kajang and Sepang, respectively) had urinary delta-ALA levels between 0.6 and 2.0 mg/100 ml. However, chi 2 analysis demonstrated significant association between delta-ALA of this group to some of the variables. The strongest association was found in the habit of biting fingernails (P < 0.025). Other statistically significant correlations were found between delta-ALA and father's occupation (P < 0.05) and the amount of time spent playing in the field (P < 0.01). Generally, this study indicates that school children in Kajang and Sepang are still relatively safe from excessively high lead exposure. However, a more sensitive indicator, which is based on a lower tolerable lead limits, such as lead in blood, are necessary to affirm this finding.
Knowledge Management (KM) addresses the critical issues of organizational adoption, survival and competence in the face of an increasingly changing environment. KM embodies organizational processes that seek a synergistic combination of the data and information processing capabilities of information and communication technologies (ICT), and the creative and innovative capacity of human beings to improve ICT In that role, knowledge management will improve quality management and avoid or minimize losses and weakness that usually come from poor performance as well as increase the competitive level of the company and its ability to survive in the global marketplace. To achieve quality, all parties including the clients, company consultants, contractors, entrepreneurs, suppliers, and the governing bodies (i.e., all involved stake-holders) need to collaborate and commit to achieving quality. The design based organizations in major business and construction companies have to be quality driven to support healthy growth in today's competitive market. In the march towards vision 2020 and globalization (i.e., the one world community) of many companies, their design based organizations need to have superior quality management and knowledge management to anticipate changes. The implementation of a quality system such as the ISO 9000 Standards, Total Quality Management, or Quality Function Deployment (QFD) focuses the company's resources towards achieving faster and better results in the global market with less cost. To anticipate the needs of the marketplace and clients as the world and technology change, a new system, which we call Power Quality System (PQS), has been designed. PQS is a combination of information and communication technologies (ICT) and the creative and innovative capacity of human beings to meet the challenges of the new world business and to develop high quality products.
Publication year= 2001 Jan-2002 Mar
Quality assurance of medical practice requires assessment of doctors' performance, whether informally via a system such as peer review or more formally via one such as credentialing. Current methods of assessment are, however, subjective or implicit. More objective methods of assessment based on statistical process control technique such as cumulative sum (CUSUM) procedure may be helpful.
Development of computer-based medical inference systems is always confronted with some difficulties. In this paper, difficulties of designing an inference system for the diagnosis of arthritic diseases are described, including variations of disease manifestations under various situations and conditions. Furthermore, the need for a huge knowledge base would result in low efficiency of the inference system. We proposed a hierarchical model of the fuzzy inference system as a possible solution. With such a model, the diagnostic process is divided into two levels. The first level of the diagnosis reduces the scope of diagnosis to be processed by the second level. This will reduce the amount of input and mapping for the whole diagnostic process. Fuzzy relational theory is the core of this system and it is used in both levels to improve the accuracy.
This paper discusses the comparative assessment of eight candidate distributions in providing accurate and reliable maximum rainfall estimates for Malaysia. The models considered were the Gamma, Generalised Normal, Generalised Pareto, Generalised Extreme Value, Gumbel, Log Pearson Type III, Pearson Type III and Wakeby. Annual maximum rainfall series for one-hour resolution from a network of seventeen automatic gauging stations located throughout Peninsular Malaysia were selected for this study. The length of rainfall records varies from twenty-three to twenty-eight years. Model parameters were estimated using the L-moment method. The quantitative assessment of the descriptive ability of each model was based on the Probability Plot Correlation Coefficient test combined with root mean squared error, relative root mean squared error and maximum absolute deviation. Bootstrap resampling was employed to investigate the extrapolative ability of each distribution. On the basis of these comparisons, it can be concluded that the GEV distribution is the most appropriate distribution for describing the annual maximum rainfall series in Malaysia.
An algorithm based on digital filtering, adaptive thresholding, statistical properties in the time domain, and differencing of local maxima and minima has been developed for the simultaneous measurement of the fetal and maternal heart rates from the maternal abdominal electrocardiogram during pregnancy and labor for ambulatory monitoring. A microcontroller-based system has been used to implement the algorithm in real-time. A Doppler ultrasound fetal monitor was used for statistical comparison on five volunteers with low risk pregnancies, between 35 and 40 weeks of gestation. Results showed an average percent root mean square difference of 5.32% and linear correlation coefficient from 0.84 to 0.93. The fetal heart rate curves remained inside a +/- 5-beats-per-minute limit relative to the reference ultrasound method for 84.1% of the time.
This study investigate the relationships between geomorphometric properties and the minimum low flow discharge of undisturbed drainage basins in the Taman Bukit Cahaya Seri Alam Forest Reserve, Peninsular Malaysia. The drainage basins selected were third-order basins so as to facilitate a common base for sampling and performing an unbiased statistical analyses. Three levels of relationships were observed in the study. Significant relationships existed between the geomorphometric properties as shown by the correlation network analysis; secondly, individual geomorphometric properties were observed to influence minimum flow discharge; and finally, the multiple regression model set up showed that minimum flow discharge (Q min) was dependent of basin area (AU), stream length (LS), maximum relief (Hmax), average relief (HAV) and stream frequency (SF). These findings further enforced other studies of this nature that drainage basins were dynamic and functional entities whose operations were governed by complex interrelationships occurring within the basins. Changes to any of the geomorphometric properties would influence their role as basin regulators thus influencing a change in basin response. In the case of the basin's minimum low flow, a change in any of the properties considered in the regression model influenced the "time to peak" of flow. A shorter time period would mean higher discharge, which is generally considered the prerequisite to flooding. This research also conclude that the role of geomorphometric properties to control the water supply within the stream through out the year even though during the drought and less precipitations months. Drainage basins are sensitive entities and any deteriorations involve will generate reciprocals and response to the water supply as well as the habitat within the areas.
A canonical/lognormal model for human demography is established, specifying the net maternity function and the age distribution for mothers of new-borns using a single macroscopic parameter vector of dimension five. The age distribution of mothers is canonical, while the net maternity function normalizes to a lognormal density. Comparison of an actual population with the model serves to identify anomalies in the population which may be indicative of phase transitions or influences from levels outside the demographic. Tracking the time development of the parameter vector may be used to predict the future state of a population, or to interpolate for data missing from the record. In accordance with classical theoretical considerations of Backman, Prigogine, et al., it emerges that the logarithm of a mother's age is the most fundamental time variable for demographic purposes.
A new method for estimating the time to colonization of Methicillin-resistant Staphylococcus Aureus (MRSA) patients is developed in this paper. The time to colonization of MRSA is modelled using a Bayesian smoothing approach for the hazard function. There are two prior models discussed in this paper: the first difference prior and the second difference prior. The second difference prior model gives smoother estimates of the hazard functions and, when applied to data from an intensive care unit (ICU), clearly shows increasing hazard up to day 13, then a decreasing hazard. The results clearly demonstrate that the hazard is not constant and provide a useful quantification of the effect of length of stay on the risk of MRSA colonization which provides useful insight.
This paper describes a model for predicting hemoglobin (Hb) by using bioelectrical impedance analysis (BIA) in dengue patients in the Hospital Universiti Kebangsaan Malaysia (HUKM). Bioelectrical impedance measurements were conducted on 83 (47 males and 36 females) serologically confirmed dengue fever (DF) and dengue hemorrhagic fever (DHF) patients during their hospitalization. The predictive equation for Hb was derived using multivariate analysis. We investigated all the parameters in BIA, patients' symptom and demographic data. In this developed model, four predictors (reactance (XC), sex, weight and vomiting) were found to be the best predictive factors for modeling Hb in dengue patients. However, the model can only explain approximately 42% of the variation in Hb status, thus single frequency bio-impedance stand-alone technique is insufficient to monitor Hb for the DF and DHF patients. Further investigation using multi-frequency BIA is recommended in modeling Hb to achieve the most parsimonious model.
A new technique based on the statistical autoregressive (AR) model has recently been developed as a solution to signal-to-noise (SNR) estimation in scanning electron microscope (SEM) images. In the present study, we propose to cascade the Lagrange time delay (LTD) estimator with the AR model. We call this technique the mixed Lagrange time delay estimation autoregressive (MLTDEAR) model. In a few test cases involving different images, this model is found to present an optimum solution for SNR estimation problems under different noise environments. In addition, it requires only a small filter order and has no noticeable estimation bias. The performance of the proposed estimator is compared with three existing methods: simple method, first-order linear interpolator, and AR-based estimator over several images. The efficiency of the MLTDEAR estimator, being more robust with noise, is significantly greater than that of the other three methods.
During the last three decades, several techniques have been proposed for signal-to-noise ratio (SNR) and noise variance estimation in images, with different degrees of success. Recently, a novel technique based on the statistical autoregressive model (AR) was developed and proposed as a solution to SNR estimation in scanning electron microscope (SEM) image. In this paper, the efficiency of the developed technique with different imaging systems is proven and presented as an optimum solution to image noise variance and SNR estimation problems. Simulation results are carried out with images like Lena, remote sensing, and SEM. The two image parameters, SNR and noise variance, are estimated using different techniques and are compared with the AR-based estimator.
In 1997, a Motorcycle Safety Programme (MSP) was introduced to address the motorcycle-related accident problem. The MSP was specifically targeted at motorcyclists. In addition to the MSP, the recent economic recession has significantly contributed to a reduction of traffic-related incidents. This paper examines the effects of the recent economic crisis and the MSP on motorcycle-related accidents, casualties and fatalities in Malaysia. The autocorrelation integrated moving average model with transfer function was used to evaluate the overall effects of the interventions. The variables used in developing the model were gross domestic product and MSPs. The analysis found a 25% reduction in the number of motorcycle-related accidents, a 27% reduction in motorcycle casualties and a 38% reduction in motorcycle fatalities after the implementation of MSP. Findings indicate that the MSP has been one of the effective measures in reducing motorcycle safety problems in Malaysia. Apart from that, the performance of the country's economy was also found to be significant in explaining the number of motorcycle-related accidents, casualties and fatalities in Malaysia.
Although extensively collected, data on people's reasons for their behaviour provided retrospectively have been met with some scepticism on the grounds that they may be subject to biases and errors that jeopardize their usefulness. This study investigates, for a sample of 1,327 births, the reliability with which women in Peninsular Malaysia recalled, at intervals 12 years apart, reasons for not initiating or for stopping breastfeeding less than 3 months after a birth. Overall, we find low to moderate reliability of recall. Levels of reliability are relatively high for some reasons (the child died and no or insufficient milk) but low for some others (child ill, breastfeeding inconvenient). Results from selection models show that reliability does not vary with the length of time since the child's birth but is inversely related to socio-economic status (proxied by education and employment). Social status, social norms, and health-related factors appear to be significant influences on women's consistency of reporting.
In this study, the growth kinetics of Lactobacillus rhamnosus and lactic acid production in continuous culture were assessed at a range of dilution rates (0.05 h(-1) to 0.40 h(-1)) using a 2 L stirred tank fermenter with a working volume of 600 ml. Unstructured models, predicated on the Monod and Luedeking-Piret equations, were employed to simulate the growth of the bacterium, glucose consumption, and lactic acid production at different dilution rates in continuous cultures. The maximum specific growth rate of L. rhamnosus, mu-max, was estimated at 0.40 h(-1), and the Monod cell growth saturation constant, Ks, at approximately 0.25 g/L. Maximum cell viability (1.3 x 10(10) CFU/ml) was achieved in the dilution rate range of D = 0.28 h(-1) to 0.35 h(-1). Both maximum viable cell yield and productivity were achieved at D = 0.35 h(-1). The continuous cultivation of L. rhamnosus at D = 0.35 h(-1) resulted in substantial improvements in cell productivity, of 267% (viable cell count) that achieved via batch cultivation.