scholarly journals Considering Abrupt Change in Rainfall for Flood Season Division: A Case Study of the Zhangjia Zhuang Reservoir, Based on a New Model

Water ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 1152 ◽  
Author(s):  
Li Tang ◽  
Yongbo Zhang

The traditional flood season division method is cumbersome. In order to make the flood season division elaborate, the Mann–Kendall and cumulative sum of rank difference (CSD) methods were used to detect the abrupt change year of precipitation (p) over the study area from 1969 to 2015. The year of change was determined to be 1995. Taking the 1995 year as a demarcation point of the data, the discriminant model and Fisher optimal partition method were applied for flood division, and a comparison of the results from the two approaches were compared. The discriminant model was found to perform slightly better than the Fisher approach. It was found that abrupt rainfall change has a certain influence on flood season division. The main flood season in the Zhangjia Zhuang reservoir during 1969–2015 was 16 days longer than during 1996–2015, but three days shorter than between 1969–1995. For the Zhangjia Zhuang Reservoir, the flood water level limit can increase up to 2 m according to the results of the flood season division and designed rainfall after abrupt change; in addition, the water storage capacity is 469 million m³ more than that of the traditional reservoir operation mode.

2013 ◽  
Vol 10 (2) ◽  
pp. 151-160

Two three dimensional Eulerian air quality models, PMCAMx and UAM-AERO are used to predict the concentrations of various pollutants in the Greater Athens Area (GAA) during the episode of June 22-26, 2003. The predicted levels of gases and aerosol pollutants are compared with measured concentrations from monitoring stations, in order to evaluate the performance of the models. Comparison of the results reveals that PMCAMx simulated the ozone diurnal pattern better than UAM-AERO, as the predicted by UAM-AERO maximum daytime concentrations were much higher than those of PMCAMx and way above the measured ones. PMCAMx also shows signs of superiority in terms of its ability to predict the NO2 and NO concentrations. Two sets of simulations, one with both anthropogenic and biogenic emissions and one without biogenic emissions were performed. Comparison of the two simulations reveals the important role that biogenic emissions play in the formation of O3, NOx and secondary aerosols. Additional simulations with PMCAMx show that the concentrations of all the pollutants depict a highly non-linear behaviour, when anthropogenic VOC emissions are reduced in the GAA.


2005 ◽  
Vol 51 (12) ◽  
pp. 325-329 ◽  
Author(s):  
X. Wang ◽  
X. Bai ◽  
J. Qiu ◽  
B. Wang

The performance of a pond–constructed wetland system in the treatment of municipal wastewater in Kiaochow city was studied; and comparison with oxidation ponds system was conducted. In the post-constructed wetland, the removal of COD, TN and TP is 24%, 58.5% and 24.8% respectively. The treated effluent from the constructed wetland can meet the Chinese National Agricultural and Irrigation Standard. The comparison between pond–constructed wetland system and oxidation pond system shows that total nitrogen removal in a constructed wetland is better than that in an oxidation pond and the TP removal is inferior. A possible reason is the low dissolved oxygen concentration in the wetland. Constructed wetlands can restrain the growth of algae effectively, and can produce obvious ecological and economical benefits.


2001 ◽  
Vol 44 (6) ◽  
pp. 109-117 ◽  
Author(s):  
M. A. Mathegana ◽  
L. K. Chauke ◽  
F. A.O. Otieno

The primary purpose of an improved water supply and sanitation is the achievement of acceptable health and hygiene standards as well as the sustainable improvement of the environment. Many governments recognize this and so they budget for large sums of money to improve these services to the communities. The purpose of this study was to investigate the different gaps in environmental health and hygiene practices with the aim of suggesting a strategy of improving this in the Northern Province of South Africa. To do this, 231 households and 30 schools were surveyed. Workshops and visits to different government departments were also used. This paper reports the results from this study which indicate that the situation in schools was not any better than that in households, with more than 90% of the villages still dependent on the unimproved pit latrines and 56,6% relying on standpipes which were (70% of the time) non-operational. The main problems identified seem to those associated with implementation and maintenance. The study concludes that with proper training of the water committees and their active involvement with the government and NGOs, environmental health and hygiene problems can be minimized or eliminated.


2002 ◽  
Vol os9 (1) ◽  
pp. 9-13 ◽  
Author(s):  
Raman Bedi ◽  
Jackie A Champion ◽  
Roger Davies

Introduction In order to promote training and education in special-needs dentistry an attempt was made to introduce problem-based learning (PBL) as a method of postgraduate dental education. The aim of this paper was to review the principles of PBL and report on a case study using this methodology. Method The case study was of a PBL session, on the subject of ‘problems of obtaining appropriate dental care for people with epilepsy’, undertaken at a national conference. Delegates were asked to complete a pre- and post-session questionnaire on PBL and their attitudes to the session. Results The session received a mixed response. Only 33 (35%) thought the session was valuable and only 20 (31%) thought it was better than conventional teaching methods and yet over half (55%) said they would like to attend more PBL in special-needs dentistry. Professionals complementary to dentistry were more likely to find the PBL session of value and to prefer the method to a more conventional format than dentists were (chi-square=5.5, df=1, p<0.05 and chi-square=5.9, df=1, p<0.05 respectively). Conclusion Valuable feedback was received from delegates. This will enable improvements to be made in future courses so that the effectiveness of PBL can be optimised.


2012 ◽  
Vol 518-523 ◽  
pp. 5886-5893
Author(s):  
Lu Cang Wang ◽  
Wei Li ◽  
Jing Gao

“The Project of Nomadic Settlement” is one of the major construction tasks for “Gannan Important Water Supply Ecological Functional Area of Yellow River”. Because of the distribution of population and settlements have obvious discreteness and wavering in alpine pasture, it is necessary to plan and guide agricultural and grazing villages during the process of the construction of nomadic settlements, spatial displacement and integration of population and settlement. The nomadic habitation mode in Luqu county undergoes four stages. At present, it adopts four settlement modes, that is, centralized settlement mode in the county town, settlement mode in the village, settlement along the highway mode and dispersed settlement mode, involving a total of 2,645households,13,783people and be arranged in 21 settlements. The paper adopts 14 indicators related conditions of economic development, social development conditions, geographic conditions, measures the overall strength of 24 administrative villages in Luqu, the whole villages are divided into four grade. The results show that the suburban villages are better than the surrounding villages and towns, pure pastoral farming are better than farming-pastoral villages. Accordingly, 24 villages are divided into four types—community-based villages, developing villages, controlling villages, and revoking-merging villages. Finally, it also proposes the path on village plan guidelines.


Author(s):  
Steven Tebby ◽  
Ebrahim Esmailzadeh ◽  
Ahmad Barari

The torsion stiffness of an automotive chassis can be determined using an analytical approach based purely on geometry, using an experimental method, or alternatively by employing a Finite Element Analysis (FEA) process. These three methods are suitable at different design stages and combined together could prove to be practical methods of determining the torsion stiffness of a chassis. This paper describes and compares two distinct FEA processes to determine the torsion stiffness of an automotive chassis during the detailed design stage. The first process iteratively applies forces to the model and records displacements, while the second process gradually applies vertical displacements in place of force to determine the torsional stiffness threshold. Each method is explained and supported with a case study to provide a basis of comparison of the results.


2020 ◽  
Vol 38 (11) ◽  
pp. 1222-1230
Author(s):  
Ricardo Herbé Cruz-Estrada ◽  
Javier Guillén-Mallette ◽  
Carlos Vidal Cupul-Manzano ◽  
Josué Iván Balam-Hernández

This work presents a study on the use of wood and plastic wastes generated in abundance in Merida, Mexico, to help to reduce them in order to mitigate environmental deterioration. The use of these wastes is proposed to obtain a low-cost building material. So, the escalation process (i.e., extrusion) at the pilot level to obtain a prototype of a wood–plastic composite (WPC) corrugated sheet to evaluate the technical feasibility to make a low-cost product is reported. A corrugated sheet with recycled high-density polyethylene (R-HDPE) was produced. The R-HDPE was collected from Merida’s Separation Plant. The wood came from the trimmings of different varieties of trees and shrubs that are periodically pruned. WPC sheets with virgin HDPE were prepared to assess its effect on the materials’ mechanical performance. The wood/HDPE weight ratio was 40/60. The performance of the WPC sheets was compared with that of commercial products with similar characteristics, namely acrylic and polyester sheets reinforced with fibreglass, and black asphalt-saturated cardboard sheets. Thus, the effect of natural weathering on the maximum tensile tearing force and on the maximum flexural load of the different types of sheets was evaluated. Although the mechanical performance of the WPC sheets was lower than that of the acrylic and polyacrylic sheets, their performance was much better than that of the cheap black asphalt-saturated cardboard sheets. So, they are a good option to be used as low-cost temporary roofing.


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