Nano-satellite attitude control system based on adaptive neuro-controller

The current research focuses on designing of an intelligent controller for attitude control system (ACS) of nano-satellite. The nanosatellite namely Innovative Satellite (InnoSAT) was organized by Agensi Angkasa Negara (ANGKASA) to attract the interest of Malaysian universities in satellite development.In this study, an intelligent controller based on Hybrid Multi Layered Perceptron (HMLP) network was developed. The network used model reference adaptive control (MRAC) system as a control scheme to control a time varying systems where the performance specifications are given in terms of a reference model.The Weighted Recursive Least Square (WRLS) algorithm will adjust the controller parameters to minimize error between the plant output and the model reference output.The objective of this paper is to analyze the tracking performance of ANC based on HMLP network and ANC based on standard MLP network for controlling a satellite attitude. The simulation results indicate that ANC based on HMLP network gave better performance than ANC based on standard MLP network

An Annotated Checklist Of Herpetofauna Of Langkawi Island, Kedah, Malaysia.

The herpetofauna ofLangkawi Island was recorded during the Scientific & Heritage Expedition ofthe Langkawi Islands, Kedah from 10 -15 April 2003. The reptiles such as snakes, lizards and turtles and amphibians such as toads and frogs were captured or observed and then identified. The reptiles and amphibians were captured and observed during trekking bouts along used and unused trails, along rivers and streams and during chance encounter

Spatial and temporal variation of amphibian assemblage at Kuala Gandah, Krau Wildlife Reserve, Pahang, Peninsular Malaysia

Recent global amphibian declines have emphasized the need for long-term, large scale monitoring programmes. Many factors have to be considered, including robust spatial sampling, duration and detectability when designing for such monitoring programmes. In this study, both active and passive sampling methods were used to increase detectability of animals. Habitat characteristics were also explored, which included disturbance history, vegetation type and microhabitat to explain species richness, relative abundance and community structure. The total species of anurans sampled from the pit-fall traps in this study was 17 species within five families, while the total of anuran species obtained from the active sampling along the rivers was 13 species from six families. The species richness could be explained significantly by two out of 10 environmental parameters measured; canopy cover and distance from forest trails, while the most abundant individuals sampled could only be explained significantly by the depth of leaf litter layer. From the cluster analysis, five main groups can be distinguished according to microhabitats, lifestyles and life cycles. Generally, disturbed habitats are characterised by widespread habitatgeneralists and/or human commensal taxa, whereas the riparian habitat and forests tend to be characterised by habitat-specialist taxa. The results of this study may assist scientists to determine trends in the selection of microhabitat by amphibians

Magnitude and risk factors for postpartum symptoms: A literature review

AbstractBackgroundThe prevalence of postpartum depression worldwide varies from 0.5% to 60.8% in the first 12 months postpartum using self-reported questionnaire. This review aims to update the current magnitude of postpartum depression based on self-reported questionnaire and clinical interview and explore its associated factors in developed and developing countries.MethodsA literature search conducted between 2005 and 2014 identified 203 studies, of which 191 used self-reported questionnaire in 42 countries and 21 used structured clinical interview in 15 countries. Nine studies used a combination of self-reported questionnaire and clinical interview.ResultThe prevalence of postpartum depression varies from 1.9% to 82.1% in developing countries and from 5.2% to 74.0% in developed countries using self-reported questionnaire. Structured clinical interview shows a much lower prevalence range from 0.1% in Finland to 26.3% in India. Antenatal depression and anxiety, previous psychiatric illness, poor marital relationship, stressful life events, negative attitude towards pregnancy, and lack of social support are significant contributors to postpartum depression.LimitationAll studies are included irrespective of the methodological quality, such as small sample size and their inclusion could affect the generalizability of the results.ConclusionThe current prevalence of postpartum depression is much higher than that previously reported, and similar risk factors are documented. A culturally sensitive cut-off score with adequate psychometric properties of the screening instruments should be available. In future studies, examining the physical, biological, and cultural factors in qualitative studies and in those with adequate methodological qualities is recommended

Nutritional composition of selected commercial biscuits in Malaysia

The objective of this study was to determine the nutrient composition of selected commercial biscuits in Malaysia. A total of six brands from each type of biscuit (chocolate chip, corn, cracker with sugar, vegetable flavoured cracker, cream filled, oatmeal, shortbread and fully coated chocolate wafer) and five brands of wholemeal crackers were sampled from local supermarkets in the Klang Valley. The total energy content in commercial biscuits was ranging from 453.30 to 499.25 kcal/100 g. Carbohydrate was the major macronutrient in commercial biscuits ranging from 56.86 to 66.07 g/100 g. The highest protein content was found in the wholemeal crackers (9.92 g/100 g) and the lowest protein content was found in the cream filled biscuits (5.65 g/100 g). Fat content lay in the range of 16.89 to 25.75 g/100 g. The major minerals detected in biscuits were sodium, followed by calcium and magnesium. The vitamin content in A and E of the biscuits examined was almost comparable. Small quantities of trans fatty acids were detected in all biscuits in the range of 0.02 to 0.68 g/100 g. These findings indicate that Malaysian commercial biscuits are a good source of carbohydrate (34.12-39.64 g per serving), calcium (26.09-384.67 g per serving), magnesium (10.42-37.24 g per serving) and contain low proportion of trans fatty acids (0.01-0.41 g per serving)

Species richness and distributional pattern of amphibians along an elevational gradient at Gunung Raya, Pulau Langkawi, Kedah, Malaysia

A study on amphibian community at Gunung Raya, Pulau Langkawi was conducted in order to identify amphibian species richness and species distribution pattern along an elevation gradient. Species richness and distribution pattern of amphibians along an elevational gradient could explain factors that determine ecological processes in a particular highland. Passive sampling method by using two types of traps namely Drift- fenced pitfall trap and PVC pipe trap were used from February 2014 until January 2015. 100 individual comprise of 10 species amphibian were recorded. Leptobrachium smithii were the most abundant (n=37) followed by Megophrys aceras (n=28). Rank abundance curve for amphibian community show a Broken Stick pattern (χ2=12.67, p=0.12). Species accumulation curve does not level off to an asymptote, indicating insufficient sample size despite intensive sampling effort. Estimation analysis by using Chao 1 predictor produces 12 amphibian species based on 100 pooled individuals. A weak positive exponential function fits the distribution pattern of amphibian abundance (y=0.0028x+13.39), reflecting species domination towards the peak. A negative exponential function fits distribution pattern of amphibian species number across the elevation gradient (y=-0.0091x+7.247), due to the lack of permanent water resource at the upper elevation. These results indicated that by understanding the upland ecology of amphibians, important decisions may be critical for designing conservation efforts and planning land use

Mating calls description of five species of frogs from the genus Hylarana Tschudi 1838 ( Amphibia, Anura, Ranidae) from Sarawak, Malaysia.

Recordings of frog calls from the genus Hylarana were conducted at seven study sites in Sarawak, Malaysia. The results showed that each species differs in terms of call characteristics, in which a high number of pulsed note belongs to H. baramica, while high repetition note belongs to the sibling species, H. glandulosa. Higher pitched and number of amplitude spectrum, however, belong to H. signata. Pulsed note and note repetition differed significantly among species, except for spectrum amplitude. Advertisement calls for each species were described in detail. This study provide a baseline data on advertisement call characteristics of frogs from the genus Hylarana for future studies of these frogs particularly and the Oriental frogs generally

The nutritional composition of fruit jams in the Malaysian market

Fruit jams are preserved fruits and sugars normally canned or sealed for long-term storage. Jam making involves the disruption of the fruit tissue followed by heating with added water and sugar to activate its pectin before being put into containers. Processes that expose foods to high levels of heat may cause some nutrient loss. Hence, the objective of this study was to evaluate the nutritional composition of four commonly consumed fruit jams that are available in the Malaysian market. Different brands (n = 6) of each type of fruit jams (grape, apricot, blueberry and strawberry) were sampled from supermarkets in Klang Valley, Malaysia. The sampling method used was stratified random sampling. The fruit jams were analyzed for the presence of 27 important nutrients using Association of Official Agricultural Chemists (AOAC) official methods of analysis. This study showed that fruit jams are a good source of energy and carbohydrate. The fruits jams have very low levels of fatty acids. Fruit jams may provide an affordable and convenient source of energy and carbohydrate. The data can be utilized to contribute to the enhancement of Malaysia Food Composition Database