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41.
S. A. Farrell R. K. Sood P. M. O'Neill 《Monthly notices of the Royal Astronomical Society》2006,367(4):1457-1462
We report the detection of a stable super-orbital period in the high-mass X-ray binary 2S 0114+650. Analyses of data from the Rossi X-ray Timing Explorer All-Sky Monitor from 1996 January 5 to 2004 August 25 reveal a super-orbital period of 30.7±0.1 d, in addition to confirming the previously reported neutron star spin period of 2.7 h and the binary orbital period of 11.6 d. It is unclear if the super-orbital period can be ascribed to the precession of a warped accretion disc in the system. 相似文献
42.
A study was carried out in district Samba of Western Himalayan province of Jammu and Kashmir of India.The data were collected in an interview schedule in personal interview with 180 household heads.The association between the level of fuelwood consumption(low versus high consumption) and different factors,each individually,was investigated using chi-square test of association at 0.001 level of significance.It was found that out of 25 socio-economic,biophysical and alternate fuel factors,15 factors(each individually) significantly influenced the domestic fuelwood consumption.Logistic regression models of alternate fuel use,social,economic and biophysical factors were developed to identify key variables influencing fuelwood consumption levels within each respective category.A composite model was also developed to identify key factors when all variables in all the pre-said categories were considered simultaneously.Surprisingly,in contrast to expectation the model with alternate fuel use did not provide a good fit.The biophysical model also did not provide a good fit.The economic and composite models were the same with equal level of accuracy of predication.This implies that economic aspects,rather than the availability of alternate fuels,dominate fuelwood consumption levels of rural households.Strategies to increase the exposure of the head of household to outside world needs to formulated to reduce the domestic fuelwood consumption levels.Households nearer to state forests are to be educated about efficient use of fuelwood and be encouraged to intensify use of Liquified Petroleum Gas.The wider implications of study are:the availability of alternate fuels is not a necessary condition to decrease household level domestic fuelwood consumption.Economic factors needs to be considered in designing strategies to reduce fuelwood consumption.Increased employment opportunities would increase the opportunity cost of fuelwood collection and this would reduce its use. 相似文献
43.
Trend analysis of water discharge and sediment load during the past three decades of development in the Langat basin,Malaysia 总被引:1,自引:0,他引:1
Abstract In this study, the trends of water discharge and sediment load from three hydrometric stations over the past 25 years of development in the state of Selangor, Peninsular Malaysia, were analysed using the Mann-Kendall and Pettitt tests. Landscape metrics for establishing the relationship between land-use changes and trends of hydrological time series were calculated. The hydrological trends were also studied in terms of rainfall variations and manmade features. The results indicate upward trends in water discharge in the Hulu Langat sub-basin and in sediment load in the Semenyih sub-basin. These increasing trends were mainly caused by rapid changes in land use. Upward trends of hydrological series in the Hulu Langat sub-basin matched its rainfall pattern. In the Lui sub-basin, however, trends of hydrological series, and variations in rainfall and land use were not statistically significant. Editor Z.W. Kundzewicz; Associate editor K. Hamed Citation Memarian, H., Balasundram, S.K., Talib, J.B., Sood, A.M., and Abbaspour, K.C., 2012. Trend analysis of water discharge and sediment load during the past three decades of development in the Langat basin, Malaysia. Hydrological Sciences Journal, 57 (6), 1207–1222. 相似文献