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81.
Kamal A. S. M. Maksud Hossain Farhad Rahman Md. Zillur Ahmed Bayes Sammonds Peter 《Landslides》2022,19(2):465-478
Landslides - The Forcibly Displaced Myanmar Nationals (FDMN), historically known as ‘Rohingya’ who fled the 2017 ethnic atrocities and genocide in the Northern Rakhine State of Myanmar,... 相似文献
82.
Tian Shufeng Chen Ningsheng Rahman Mahfuzur Hu Guisheng Peng Taixin Zhang Yong Liu Mei 《Landslides》2022,19(3):647-657
Landslides - In 2019, the catastrophic Zhaiban slope debris flow (ZSDF) crushed an open road tunnel in Ganluo County, Sichuan Province, China, causing seven deaths and interrupting traffic flow for... 相似文献
83.
Acta Geotechnica - Fabric anisotropy and fines content (fc) in sands modify significantly their mechanical behaviour, particularly as related to static liquefaction under undrained conditions. The... 相似文献
84.
Sanzidur Rahman Ismat Ara Begum Mohammad Jahangir Alam 《Singapore journal of tropical geography》2012,33(2):241-254
This paper re‐examines the effect of green revolution (GR) diffusion on factor/inputs demand in Bangladesh using an empirical model that allows for simultaneous determination of factors influencing adoption of GR technology at the current mature stage, as well as access to irrigation. Results reveal some alignments with conventional wisdom as well as few surprises. For example, while an increased demand for major inputs is expected, an increased demand for organic manure is an unexpected positive outcome. The GR adoption rate is significantly higher in villages with access to irrigation and fertile soils and, surprisingly, in infrastructurally underdeveloped villages. Together with other expected findings of GR technology uptake with higher cereal prices and irrigation use encouraged by access to credit, tenurial status and fertile soils, our findings suggest that investment in irrigation and soil conservation, as well as implementing measures to improve cereal prices and provide agricultural credit, could boost GR technology adoption. 相似文献
85.
Turbulent surface heat fluxes (latent and sensible heat) are the two most important parameters through which air–sea interaction takes place at the ocean–atmosphere interface. These fluxes over the global ocean are required to drive ocean models and to validate coupled ocean–atmosphere global models. But because of inadequate in situ observations these are the least understood parameters over the tropical Indian Ocean. Surface heat fluxes also contribute to the oceanic heat budget and control the sea surface temperature in conjunction with upper ocean stratification and ocean currents. The most widely used flux products in diagnostic studies and forcing of ocean general circulation models are the ones provided by the National Centres for Environment Prediction (NCEP) reanalysis. In this study we have compared NCEP reanalysed marine meteorological parameters, which are used for turbulent heat fluxes, with the moored buoy observation in the south-eastern Arabian Sea. The NCEP latent heat flux (LHF) and sensible heat flux (SHF) derived from bulk aerodynamic formula are also compared with that of ship and buoy derived LHF and SHF. The analysis is being carried out during the pre-monsoon and monsoon season of 2005. The analysis shows that NCEP latent as well as sensible heat fluxes are largely underestimated during the monsoon season, however, it is reasonably comparable during the pre-monsoon period. This is largely due to the underestimation of NCEP reanalysis air temperature (AT), wind speed (WS) and relative humidity (RH) compared to buoy observations. The mean differences between buoy and NCEP parameters during the monsoon (pre-monsoon) period are ~21% (~14%) for WS, ~6% (~3%) for RH, and ~0.75% (0.9%) for AT, respectively. The sudden drop in AT during rain events could not be captured by the NCEP data and, hence, large underestimations in SHF. During the pre-monsoon period, major contribution to LHF variations comes from WS, however, both surface winds and relative humidity controls the LHF variations during the monsoon. LHF is mainly determined by WS and RH during the monsoon and, WS is the main contributor during the pre-monsoon. 相似文献
86.
Arsenic contamination of ground and pond water and water purification system using pond water in Bangladesh 总被引:1,自引:0,他引:1
H. Yokota K. Tanabe M. Sezaki Y. Akiyoshi T. Miyata K. Kawahara S. Tsushima H. Hironaka H. Takafuji M. Rahman Sk. A. Ahmad M. H. S. U. Sayed M. H. Faruquee 《Engineering Geology》2001,60(1-4):323-331
This paper, firstly, shows the distribution of arsenic-contaminated groundwater in Samta village. This village, which is in Jessore district in Bangladesh, was chosen as a model village for investigating the mechanism of groundwater contamination. 90% of the tube wells in this village had arsenic concentrations above the Bangladesh standard of 0.05 mg/l. Tube wells with arsenic concentrations of over 0.50 mg/l were distributed in the southern part of the village with a belt-like shape from east to west. Secondly, groundwater distribution is discussed with respect to its flow and the high arsenic zone (As≥0.50 mg/l) agrees well with the drifting zone of the groundwater. Furthermore, arsenic-free water supply systems suitable for a small area in the village have been developed. A pond sand filter (PSF) system which purifies pond water is discussed in this paper. Prior to the construction of the PSF, the water quality in ponds was examined for arsenic levels. The inflow of drainage from the tube wells was found to be the major cause of arsenic contamination of pond water. The PSF installed in Samta is working very well and produces a good quality of treated water. 相似文献
87.
200 kV and 300 kV HREM images of mullite with beam direction parallel to [010] and [100] have been compared with extensive multi-slice calculations of structure models with different oxygen vacancy arrangements. The simulations reveal that changes of the contrast pattern in HREM images are correlated with enhanced vacancy concentrations and coupled cation shifts (Al*). Furthermore, the direct relationship between contrast variation and projected vacancy concentration permits the detection of 20% oxygen vacancies along [010] and [100]. An analysis of HREM images indicates preferred orientations of vacancies parallel to 〈102〉 in the (010) plane, whereas the (010) plane yields arrangements parallel to 〈012〉 and 〈001〉, resulting in an average direction of 〈013〉. Distances of 1.5a and 1.5b between these arrangements result from preferred inter-vacancy correlation vectors of 1/2 〈310〉 and 1/2 〈130〉 in the (001) plane. The investigated 2:1 and 3:2-mullites (x = 0.40 and x = 0.25) do not show long-range ordered arrangements of oxygen vacancies, but reveal the composition-dependent formation of short-range order regions of enhanced vacancy concentrations. These regions are distributed in a matrix with a minor degree of order. 相似文献
88.
Chu-fa Tsai M. Nazrul Islam Rezaul Karim MD K. U. M. Shahidur Rahman 《Estuaries and Coasts》1981,4(2):127-138
Spawning biology and spawn fishery of three valuable species of Indian major carps,Catla catla, Labeo rohita andCirrhinus mrigala, in the lower Halda River, Bangladesh, were studied in 1978. The major carps spawned only in the Sonairchar oxbow-bend from April to June on or near the dates of the full moon and the new moon. The tide was then at its highest level, and there was heavy flood water runoff from the hill region with sharp increases in water level, turbidity and current velocity, as well as decreases in water temperature, dissolved oxygen, and hydrogen ion concentration. These three heterogeneric species, as a result of parallelism or convergence in evolution, overlap in their environmental requirements for spawning. The nursery ground of the major carp fry spawned in the Halda River was found to be in the Bay of Bengal. The brood stock origin is suspected to be at the Shankha River, 40 miles south of the Karnafuli River. The spawn fishery in the Halda River was intensive but inefficient. Engineering works and water management schemes are threatening the spawning habitat. 相似文献
89.
Atiqur Rahman 《GeoJournal》2006,65(3):211-227
The main objectives of the present study are: (i) to assess the income-wise household environmental conditions of the sampled
households in Aligarh city, (ii) to examine income-wise disease profile of the population, (iii) to assess the relationship
between income and four most occurring diseases, (iv) draw out inter-relationship between income, non-ideal household environmental
conditions and environment related diseases. The quality of life and diseases in any urban areas get reflected by the immediate
neighborhood in different parts of the city which depends upon the income strata of the households, their way of living, and
their understanding of their household environment. This is because it is the household environment, which exerts the most
and immediate influence on the life of the people. This study was carried out in order to assess household environmental conditions
(i.e. housing conditions, bathroom and sanitation conditions, water supply conditions, water logging conditions, household
garbage and solid waste, household pests, indoor air and indoor noise pollution) and their effect on the health of the resident
population of Aligarh city. The method includes household survey of Aligarh city using questionnaires. The sampled households
were classified into five income groups from very low to very high. Relationship was tested between income and household environmental
conditions and also between income and diseases using Chi-Square technique. About 55% of the total sampled households suffer
from diarrhea/dysentery, 43% jaundice, 42% malaria and 41% respiratory diseases. About 40% suffer from skin diseases, small
pox/chicken pox. All these diseases are a result of poor household environmental conditions. Whereas 35% people reported other
diseases (i.e. heart disease, hypertension and diabetes), only 14.42% households reported of tuberculosis. The study concludes
that there exists a significant positive relationship between income level and household environmental conditions, and also
between income and various diseases among sampled households of Aligarh city. 相似文献
90.
Summary The summer monsoon onset-2004 over the Kerala Coast (Southern tip of the Indian Peninsula) was monitored in real-time using
the Tropical Rainfall Measuring Mission (TRMM)/TMI derived total precipitable water vapor, wind speed and sea surface temperature
(SST), National Centre for Environmental Prediction (NCEP) and QuikScat wind data. The 2004 onset was of a gradual type, with
an early start (24 May), followed by slow growth to full strength (10 June). Hence, the unambiguous forecasting of such onsets
becomes very difficult. The water vapor build up over the western Arabian Sea is one of the necessary conditions that gives
us a lead time of two and half weeks for the onset of monsoon. The strength of the Hadley cell (monitored using NCEP meridional
wind), which is associated with a large convective heat source is also used as a predictive parameter with a lead-time of
two weeks. The other dynamical conditions considered are the early May propagation of the Madden Julian Oscillation (MJO)
followed by a second MJO, which began in the Western Indian Ocean (WIO) and the kinetic energy over the South East Arabian
Sea, with an early start around 24 May (50 m2/s2) and strengthening around 10 June (80 m2/s2). The setting of large-scale monsoon current using various satellite derived parameters and the distinct features for the
year 2004 have been delineated. 相似文献