338 research outputs found

    Sedimentological characteristics of sediments of the South China Sea, Area II: Sarawak, Sabah and Brunei Darussalam waters

    Get PDF
    Surficial investigation of bottom sediments was conducted within the waters off the coast of Sabah, Sarawak and Brunei Darussalam. Two sampling of bottom sediments were conducted, one before (September 1996) and one after (April 1997) the Northeast monsoon period, which normally lasts from November to February annually. During the pre-monsoon cruise, fifty-one samples were collected while 52 samples were collected during the post-monsoon exercise. The collected samples were analysed for their sedimentological characteristics of mean, sorting, skewness and kurtosis. Analyses revealed that the post-monsoon sediments are finer, better sorted in arrangement, more symmetrical and less peaked than the pre-monsoon sediments. Deeper water sediment shows the same characteristics as described above when compared to shallow water sediments. In general, the near-shore sediments are coarsest, more poorly sorted, more positively skewed and most peaked in characteristics when compared to the mid-shore and off-shore sediments

    Sedimentological characteristics of the sediments of the South China Sea, Area I: Gulf of Thailand and east coast of Peninsular Malaysia

    Get PDF
    Two batches of eighty sediment samples were cut from the first centimeter of sediment cores collected during September 1995, representing the pre-monsoon period, and April 1996, representing the post-monsoon period, at the same location. The samples were collected within the waters of the Gulf of Thailand and the eastern board of Peninsular Malaysia. The sediment samples were analyzed for their sedimentological characteristics using the techniques of sieving and laser diffraction. In general the sediments of the Gulf of Thailand are finer, better sorted, more peaked than that of the Malaysian waters. Skewness of sediments from Thailand waters was more positively skewed than the Malaysian sediments for the pre-monsoon period but tended to be more negatively skewed for the post-monsoon period. It is also interesting to note that in general, the sediments collected during the post-monsoon period are finer, better sorted, more positively skewed and less peaked than the sediments collected during the pre-monsoon period. This is true for both the sediments collected from the Gulf of Thailand and the Malaysian waters. Near-shore sediments were also found to be the coarsest, followed by the off-shore sediments

    New Nonthermal Filaments at the Galactic Center: Are They Tracing a Globally Ordered Magnetic Field?

    Full text link
    New high-resolution, wide-field 90 cm VLA observations of the Galactic Center region by Nord et al. have revealed twenty nonthermal filament (NTF) candidates. We report 6 cm polarization observations of six of these. All of the candidates have the expected NTF morphology, and two show extended polarization confirming their identification as NTFs. One of the new NTFs appears to be part of a system of NTFs located in the Sgr B region, 64 pc in projection north of Sgr A. These filaments cross the Galactic plane with an orientation similar to the filaments in the Galactic Center Radio Arc. They extend the scale over which the NTF phenomena is known to occur to almost 300 pc along the Galactic plane. Another NTF was found in the Galactic plane south of the Sgr C filament but with an orientation of 45 degrees to the Galactic plane. This is only the second of 12 confirmed NTFs that is not oriented perpendicular to the Galactic plane. An additional candidate in the Sgr C region was resolved into multiple filamentary structures. Polarization was detected only at the brightness peak of one of the filaments. Several of these filaments run parallel to the Galactic plane and can be considered additional evidence for non-poloidal magnetic fields at the GC. Together the 90 and 6 cm observations indicate that the Galactic center magnetic field may be more complex than a simple globally ordered dipole field.Comment: Astrophysical Journal, Accepte

    An Assessment of Risk of Iodine Deficiency Among Pregnant Women in Sarawak, Malaysia

    Full text link
    Previous findings from a state-wide Iodine Deficiency Disorders (IDD) study among pregnant women (PW) in Sarawak indicated that PW are at risk of IDD and further assessment is needed. This paper describes the methodology used in conducting this study for an assessment of risk of iodine deficiency among pregnant women in Sarawak, Malaysia. A total of 30 maternal child health care clinics (MCHCs) were selected using probability proportional to population size (PPS) sampling technique. The PW sample size was calculated based on 95% confidence interval (CI), relative precision of 5%, design effect of 2, anticipated IDD prevalence of 65.0% and non-response rate of 20%. Thus, the total sample size required was 750 (25 respondents per selected MCHC). The WHO Expanded Programme on Immunization (EPI) surveys approach was used to randomly select the first respondent and subsequent respondents were chosen until the required number of PW was met. The required data were obtained through: face-to-face interviews (socio-demographic and food frequency questionnaire), clinical assessments (thyroid size, and hyper/hypothyroidism) and biochemical analysis (urine and blood serum). A total of 677 PW responded in the study with a response rate of 90.2%. Majority of the PW were at second gravida, aged 25-29 years old and of Malay ethnicity. The methodology used in this study was based on International guidelines which may provide state's estimates. All the necessary steps were taken into consideration to ensure valid and reliable findings on current iodine status among PW

    Canonical Particle Acceleration in FRI Radio Galaxies

    Full text link
    Matched resolution multi-frequency VLA observations of four radio galaxies are used to derive the asymptotic low energy slope of the relativistic electron distribution. Where available, low energy slopes are also determined for other sources in the literature. They provide information on the acceleration physics independent of radiative and other losses, which confuse measurements of the synchrotron spectra in most radio, optical and X-ray studies. We find a narrow range of inferred low energy electron energy slopes, n(E)=const*E^-2.1 for the currently small sample of lower luminosity sources classified as FRI (not classical doubles). This distribution is close to, but apparently inconsistent with, the test particle limit of n(E)=const*E^-2.0 expected from strong diffusive shock acceleration in the non-relativistic limit. Relativistic shocks or those modified by the back-pressure of efficiently accelerated cosmic rays are two alternatives to produce somewhat steeper spectra. We note for further study the possiblity of acceleration through shocks, turbulence or shear in the flaring/brightening regions in FRI jets as they move away from the nucleus. Jets on pc scales and the collimated jets and hot spots of FRII (classical double) sources would be governed by different acceleration sites and mechanisms; they appear to show a much wider range of spectra than for FRI sources.Comment: 16 figures, including 5 color. Accepted to Astrophysical Journa

    Quality of life satisfaction among converted Kelantan Chinese Muslims

    Get PDF
    This article investigates the quality of life of the Kelantan Chinese Muslim community before and after conversion to Islam, focusing on their level of satisfaction in term of economic aspect. This research was carried out using the sequential explanatory mixed method design involving 75 respondents selected for quantitative and five respondents for qualitative. The sampling method adopted was convenience and snowball samplings. The research data was collected using questionnaires and semi-structured interviews. The results revealed that respondents were moderately satisfied before conversion and satisfied after conversion. Besides that, there is no significant difference of quality of life before and after conversion to Islam (F = 0.868, p = 0.355) and it was not influenced by the period of conversion to Islam (F = 0.832, p = 0.589). This analysis indicates numerous respondents are still moderately satisfied in their quality of life even though the average data shows they are satisfied after conversion

    A statistical downscaling framework for environmental mapping

    Get PDF
    In recent years, knowledge extraction from data has become increasingly popular, with many numerical forecasting models, mainly falling into two major categories—chemical transport models (CTMs) and conventional statistical methods. However, due to data and model variability, data-driven knowledge extraction from high-dimensional, multifaceted data in such applications require generalisations of global to regional or local conditions. Typically, generalisation is achieved via mapping global conditions to local ecosystems and human habitats which amounts to tracking and monitoring environmental dynamics in various geographical areas and their regional and global implications on human livelihood. Statistical downscaling techniques have been widely used to extract high-resolution information from regional-scale variables produced by CTMs in climate model. Conventional applications of these methods are predominantly dimensional reduction in nature, designed to reduce spatial dimension of gridded model outputs without loss of essential spatial information. Their downside is twofold—complete dependence on unlabelled design matrix and reliance on underlying distributional assumptions. We propose a novel statistical downscaling framework for dealing with data and model variability. Its power derives from training and testing multiple models on multiple samples, narrowing down global environmental phenomena to regional discordance through dimensional reduction and visualisation. Hourly ground-level ozone observations were obtained from various environmental stations maintained by the US Environmental Protection Agency, covering the summer period (June–August 2005). Regional patterns of ozone are related to local observations via repeated runs and performance assessment of multiple versions of empirical orthogonal functions or principal components and principal fitted components via an algorithm with fully adaptable parameters. We demonstrate how the algorithm can be extended to weather-dependent and other applications with inherent data randomness and model variability via its built-in interdisciplinary computational power that connects data sources with end-users
    • …
    corecore