RESUMO
Accurate calculation of flow discharge for sluice gates is essential in irrigation, water supply, and structure safety. The measurement of discharge with the requirement of distinguishing flow regimes is not conducive to application. In this study, a novel approach that considers both free and submerged flow was proposed. The energy-momentum method was employed to derive the coefficient of discharge. Subsequently, the discharge coefficient was determined through the experiment which was performed on the physical model of a vertical sluice gate with a broad-crested weir. Feature engineering, incorporating dimensional analysis, feature construction, and correlation-based selection were performed. The best subset regression method was employed to develop regression equations of the discharge coefficient with the generated features. The derived formula was applied to compute the discharge coefficient in the vertical sluice gate and determine the flow discharge. The accuracy of adopted method was assessed by comparing it with recent studies on submerged flow, and the results demonstrate that the developed approach achieves a high level of accuracy in calculating flow discharge. The coefficient of determination for the calculated flow rate is 0.993, and the root mean square percentage error is 5.04%.
Assuntos
Abastecimento de ÁguaRESUMO
OBJECTIVES: To observe the clinical efficacy of timing umbilical therapy for neurogenic bladder after spinal cord injury based on the midnight-noon and ebb-flow doctrine. METHODS: Sixty patients with neurogenic bladder after spinal cord injury were randomly divided into a trial group and a control group, with 30 patients in each group. In the trial group, based on the midnight-noon and ebb-flow doctrine, umbilical therapy was given at the time zone, 15:00 to 17:00. In the control group, umbilical therapy was delivered at any time zones except the period 15:00 to 17:00. The herbal plaster was remained on the umbilicus for 4 h each time, once daily. One course of treatment was composed of 2 weeks and the treatment lasted 4 weeks. Before and after treatment, the urodynamic indexes (maximum urinary flow rate [Qmax], maximum detrusor pressure [Pdet-max], residual urine volume [RUV]), voiding diary (average daily number of voiding, average daily number of leakage, average daily voided volume), neurogenic bladder symptom score (NBSS), the score of urinary symptom distress scale (USDS) and the score of World Health Organization quality of life assessment-BREF (WHOQOL-BREF) were compared between the two groups; and the clinical efficacy of the two groups was assessed. RESULTS: After treatment, Qmax, Pdet-max, the average daily voided volume and the scores of WHOQOL-BREF were increased (P<0.05); and RUV, the average daily number of voiding, the average daily number of leakage, NBSS and the scores of USDS were all reduced (P<0.05) in comparison with those before treatment in the two groups. When compared with those in the control group, Qmax, Pdet-max, the average daily voided volume and the score of WHOQOL-BREF were all higher (P<0.05); and RUV, the average daily number of voiding, the average daily number of leakage, NBSS and the score of USDS were lower (P<0.05) in the trial group. The total effective rate was 96.7% (29/30) in the trial group, higher than that (76.7%, 23/30) in the control group (P<0.05). CONCLUSIONS: Timing umbilical therapy, based on the midnight-noon and ebb-flow doctrine, effectively relieves the symptoms of dysuria and improves the quality of life in patients with neurogenic bladder after spinal cord injury.
Assuntos
Traumatismos da Medula Espinal , Bexiga Urinaria Neurogênica , Humanos , Bexiga Urinaria Neurogênica/etiologia , Bexiga Urinaria Neurogênica/terapia , Qualidade de Vida , Umbigo , Bexiga Urinária , Traumatismos da Medula Espinal/complicaçõesRESUMO
The collapse mechanism of dual-structure vegetation riverbanks at different water levels is unclear. A method for calculating the critical collapse width of a dual-structure vegetation bank under different failure modes that consider the variations in river and groundwater levels and the influence of vegetation roots is proposed. Combined with the influence of flow lateral erosion and slope toe accumulation, a calculation model of riverbank stability was established. The results show that shear failure is the main failure mode when the cohesive soil layer on a dual-structure bank is thick, and the critical collapse width of the bank with root soil is higher than that of the soil bank. The critical collapse width of the bank varied with the water level during different water level periods. Compared with a soil riverbank, a rooted soil riverbank can significantly prolong the bank collapse time. The collapse width of a soil bank without vegetation roots is smaller than that of a rooted soil bank, and the cumulative collapse width is related to calculation time. The greater the thickness of rooted soil, the slower the decay rate of bank stability under water flow erosion.
Assuntos
Solo , Água , Solo/química , RiosRESUMO
Green roof is widely used in advanced stormwater management as a major measure now. Taking Huxi catchment in Chongqing University as the study area, the relationships between green roof installation with runoff volume and water quality in urban region were investigated. The results showed that roof greening in the urban region contributed to reducing the runoff volume and pollution load. In addition, the spatial distribution and area of green roof also had effects on the runoff water quality. With the conditions that the roof area was 25% of the total watershed area, rainfall duration was 15 min and rainfall intensity was 14.8 mm x h(-1), the peak runoff and total runoff volume were reduced by 5.3% and 31%, the pollution loads of total suspended solid (TSS), total phosphorus (TP) and total nitrogen (TN) decreased by 40.0%, 31.6% and 29.8%, their peak concentrations decreased by 21.0%, 16.0% and -12.2%, and the EMCs (event mean concentrations) were cut down by 13.1%, 0.9% and -1.7%, respectively, when all impervious roofs were greened in the research area. With the increase of roof greening rate, the reduction rates of TSS and TP concentrations increased, while the reduction rate of TN concentration decreased on the whole. Much more improvement could be obtained with the use of green roofs near the outlet of the watershed.
