Water Resources Management - In arid and semi-arid regions, groundwater is considered being the most available natural resources for different water use. However, it is being limited in... 相似文献
Accurate prediction of shear force distribution along the boundary in open channels is a key to the solution of numerous hydraulic problems. The problem becomes more complicated for meandering compound channels. A model is developed for predicting the percentage of shear force at the floodplain (%Sfp) of two-stage meandering channels using gene-expression programming (GEP) by considering five dimensionless parameters viz. the width ratio, relative depth, sinuosity, bed slope, and meander belt width ratio as the inputs in the model. Basing on the %Sfp, the apparent shear force along the division lines of separation in compound channels is selected for discharge calculation using the conventional channel division methods. An Enhanced Channel Division Method (ECDM) is introduced to calculate discharge by assuming interface line at main channel and floodplain junction. A modified variable-inclined (MVI) interface is suggested having zero apparent shear determined from flow contribution in the main channel and floodplain. The MVI interface is further used to calculate discharge in the meandering compound channels. Performance of the GEP model is tested against other analytical methods of calculating %Sfp. Error between the observed and calculated discharges using the MVI interface is found to be the minimum when compared to other interface methods. The enhance channel division method is successfully applied for validating the two available overbank discharge values for the river Baitarani at Anandapur (drainage area of 8570 sq. km), giving the minimum errors of 0.31% and 1.02% for flow depths of 7.5 m and 8.63 m, respectively.
The cycle rickshaw is a popular transportation device. The aim of the study was to assess workload of cycle rickshaw pullers--physiological and subjective at four different places in India. Subjects were instructed to pull a cycle rickshaw with two passengers, for 20 min. Working and recovery heart rates were recorded. The mean values of energy expenditure of pulling a cycle rickshaw varied from 23.5 +/- 2.66 to 25.35 +/- 1.51 kJ/min. Relative cardiac strain and cardiac cost indicated that the job is 'heavy' to 'very heavy'. Subjective assessment of workload was 'heavy' to 'very heavy'. The combined workload assessed from physiological parameters and subjective assessment indicated that the job could be categorised as 'heavy' to 'very heavy' at all the places studied and needs to be reduced by redesigning the structural and functional components of the cycle rickshaw. The rickshaw pullers carry out the jobs many times per day, sometimes without proper rest pauses between trips. The outcome of the research project is beneficial for cycle rickshaw pullers, health administrators as well as manufacturers of cycle rickshaws. Primarily, the manufacturers would be able to use the data for producing a newer model of cycle rickshaw, which would require less energy to drive. The health administrators would be able to take policy decisions for administering better health care for the unorganised and underprivileged workers. The pullers could be guided into taking care of their health by improving their work practice, i.e. taking a sufficient rest pause between trips. 相似文献
OBJECTIVE: Evaluation of the effects of a PC-based training program on risk perception in a driving simulator. BACKGROUND: Novice drivers have a fatality rate some eight times higher than that of the most experienced group of drivers, primarily because of the novice driver's inability to predict ahead of time the risks that will appear in the roadway. Current driver education programs, at least those in the United States, do not emphasize the teaching of risk awareness skills to novice drivers. METHOD: A PC-based risk awareness and perception training program was developed and evaluated. The training involved using plan (top-down) views of 10 risky scenarios that helped novice drivers identify where potential risks were located and what information should be attended. Both the 24 trained novice drivers and 24 untrained novice drivers were evaluated on an advanced driving simulator. The eye movements of both groups of drivers were measured. The evaluation on the driving simulator included both scenarios used in the training and others not used in training. RESULTS: The set of trained novice drivers were almost twice as likely as untrained drivers to fixate appropriately either on the regions where potential risks might appear or on signs that warned of potentially risky situations ahead, both for the scenarios they had encountered in training and for novel scenarios. APPLICATION: The PC training program developed, which is portable and can be widely used, has great promise in improving risk perception for novice drivers on the road. 相似文献
Producing accurate land-use and land-cover (LULC) mapping is a long-standing challenge using solely optical remote-sensing data, especially in tropical regions due to the presence of clouds. To supplement this, RADARSAT images can be useful in assisting LULC mapping. The fusion of optical and active remote-sensing data is important for accurate LULC mapping because the data from different parts of the spectrum provide complementary information and often lead to increased classification accuracy. Also, the timeliness of using synthetic aperture radar (SAR) fills information gaps during overcast or hazy periods. Therefore, this research designed a refined classification procedure for LULC mapping for tropical regions. Determining the best method for mapping with a specific data source and study area is a major challenge because of the wide range of classification algorithms and methodologies available. In this study, different combinations and the potential of Landsat Operational Land Imager (OLI) and RADARSAT-2 SAR data were evaluated to select the best procedure for LULC classification. Results showed that the best filter for SAR speckle reduction is the 5 × 5 enhanced Lee. Furthermore, image-sharpening algorithms were employed to fuse Landsat multispectral and panchromatic bands and subsequently these algorithms were analysed in detail. The findings also confirmed that Gram–Schmidt (GS) performed better than the other techniques employed. Fused Landsat data and SAR images were then integrated to produce the LULC map. Different classification algorithms were adopted to classify the integrated Landsat and SAR data, and the maximum likelihood classifier (MLC) was considered the best approach. Finally, a suitable classification procedure was designed and proposed for LULC as mapping in tropical regions based on the results obtained. An overall accuracy of 98.62% was achieved from the proposed methodology. The proposed methodology is a useful tool in industry for mapping purposes. Additionally, it is also useful for researchers, who could extend the method for different data sources and regions. 相似文献
A study was designed to evaluate physiological cost and work performance of lower extremity disabled people with reference to hand-cranked tricycle propulsion. Eleven volunteers took part in this study. For an average body weight of 39.7 kg, VO2 max (arm cranking) was only 0.777 l/min at STPD. The pulmonary demand and oxygen uptake of the disabled subjects during tricycle propulsion at 8.45 +/- 0.6 km/h corresponded to about 70% of their maximal response; hence, work stress was categorised as heavy. Mechanical efficiency of cranking was best when a hand-rim propulsion system was arranged for two-arm cranking at the heart level of the disabled person and at a cranking pace of 60 rev/min. 相似文献
This study aims to investigate the impact of the Three-Dimensional Variational (3DVAR) assimilation of Doppler Weather Radar (DWR) wind data together with the India Meteorological Department (IMD) upper air and surface data for the prediction of a tropical cyclone, which formed over the Bay of Bengal. The National Centers for Environmental Prediction Final Analyses (NCEP FNL) data are used to produce initial conditions. Three numerical experiments were designed to study the effect of 3DVAR assimilation. For the first experiment, the model integrations were performed without any assimilation of observations. IMD upper air and surface observations were assimilated using 3DVAR for the second experiment and the third experiment assimilated DWR wind data along with IMD observations. The model results are compared with one another and also with the observations. The results of the study indicate that the assimilation of DWR wind data and IMD data have resulted in improvements in the simulation of strong vertical velocity, higher warm core temperature and strong gradients in the horizontal wind speed as well as improved spatial distribution of the precipitation. 相似文献
Dietary patterns in 81 rural Nepali households with a 1-6-y-old child with a history of xerophthalmia were compared with dietary patterns of 81 households with an age-matched nonxerophthalmic control subject. Weekly food-frequency questionnaires were collected from case and control "focus" children, a younger sibling (if present), and the household 1-2 y after recruitment and treatment of cases. Control households and children were more likely than case households and children to consume vitamin A-rich foods during the monsoon (July-September) and major rice harvesting (October-December) seasons. Cases were less likely to consume preformed vitamin A-rich foods throughout the year [odds ratio (OR) = 1.2-4.5] with the strongest differences observed from October to December (OR = 2.0-4.2). Dietary risks were generally shared by younger siblings of cases, suggesting that infrequent intake of beta-carotene and preformed vitamin-A rich foods begins early in life and clusters among siblings within households, a pattern that is consistent with their higher risk of xerophthalmia and mortality. In developing countries where vitamin A deficiency is endemic, dietary counseling for children with xerophthalmia should be extended to their younger siblings. Moreover, dietary intake of preformed vitamin A may be as, or more, important as carotenoid-containing food consumption in protecting children and other members of households from vitamin A deficiency. 相似文献
This study analyzes the effect of degradation on human and automatic speaker verification (SV) tasks. The perceptual test
is conducted by the subjects having knowledge about speaker verification. An automatic SV system is developed using the Mel-frequency
cepstral coefficients (MFCC) and Gaussian mixture model (GMM). The human and automatic speaker verification performances are
compared for clean train and different degraded test conditions. Speech signals are reconstructed in clean and degraded conditions
by highlighting different speaker specific information and compared through perceptual test. The perceptual cues that the
human subjects used as speaker specific information are investigated and their importance in degraded condition is highlighted.
The difference in the nature of human and automatic SV tasks is investigated in terms of falsely accepted and falsely rejected
speech pairs. Speech signals are reconstructed in clean and degraded conditions by highlighting different speaker specific
information and compared through perceptual test. A discussion on human vs automatic speaker verification is carried out and
the possibility of performance improvement of automatic speaker verification under degraded condition is suggested. 相似文献