scholarly journals Network Flow Analysis under Water Shortage and Decompressed Water Supply Control

2003 ◽  
Vol 123 (8) ◽  
pp. 1449-1455
Author(s):  
Hiromitsu Kurisu ◽  
Takashi Fukumoto ◽  
Hideyuki Tadokoro ◽  
Norihisa Komoda
Keyword(s):  
Water Supply ◽  
Network Flow ◽  
Flow Analysis ◽  
Water Shortage

scholarly journals Assessment of optimal empty flushing strategies in a multi-reservoir system

2016 ◽  
Author(s):  
Frederick N.-F. Chou ◽  
Chia-Wen Wu
Keyword(s):  
Water Supply ◽  
Network Flow ◽  
Operation Mode ◽  
Water Shortage ◽  
Maximum Amount ◽  
Optimal Parameters ◽  
Joint Operation ◽  
Reservoir System ◽  
Network Flow Programming ◽  
Nonlinear Optimization Algorithm

Abstract. Empty flushing is the most effective approach to evacuate the deposited sediments in the reservoir. However, emptying reservoir essentially conflicts with its water supply operation, thus a feasible strategy of empty flushing should prevent significant increase of water shortage risks. This paper presents a framework of performing empty flushing in a multi-reservoir system, where flushing is carried out in a primary reservoir and the other reservoirs provide backup storage for stable water supply during flushing. A network flow programming-based model is employed to simulate daily joint operation of reservoirs. During the simulation, if the storage of each reservoir achieves the predefined conditions, drawdown and empty flushing of the primary reservoir is activated. During the flushing, if the storage of any reservoir reaches the pre-defined thresholds, then the flushing operation is halted and the simulation switches back to the regular joint operation mode. This simulation model is linked with a nonlinear optimization algorithm to calibrate the optimal parameters. The optimized strategy yields a maximum amount of flushed sediments, while the incremental water shortage is controlled within the acceptable threshold.

scholarly journals Traffic Inequality and Relations in Maritime Silk Road: A Network Flow Analysis

2021 ◽  
Vol 10 (1) ◽  
pp. 40
Author(s):  
Naixia Mou ◽  
Haonan Ren ◽  
Yunhao Zheng ◽  
Jinhai Chen ◽  
Jiqiang Niu ◽  
...  
Keyword(s):  
Traffic Flow ◽  
Network Flow ◽  
Road Traffic ◽  
Flow Analysis ◽  
Silk Road ◽  
Identification System ◽  
Traffic Network ◽  
Trajectory Data ◽  
Maritime Traffic ◽  
Maritime Silk Road

Maritime traffic can reflect the diverse and complex relations between countries and regions, such as economic trade and geopolitics. Based on the AIS (Automatic Identification System) trajectory data of ships, this study constructs the Maritime Silk Road traffic network. In this study, we used a complex network theory along with social network analysis and network flow analysis to analyze the spatial distribution characteristics of maritime traffic flow of the Maritime Silk Road; further, we empirically demonstrate the traffic inequality in the route. On this basis, we explore the role of the country in the maritime traffic system and the resulting traffic relations. There are three main results of this study. (1) The inequality in the maritime traffic of the Maritime Silk Road has led to obvious regional differences. Europe, west Asia, northeast Asia, and southeast Asia are the dominant regions of the Maritime Silk Road. (2) Different countries play different maritime traffic roles. Italy, Singapore, and China are the core countries in the maritime traffic network of the Maritime Silk Road; Greece, Turkey, Cyprus, Lebanon, and Israel have built a structure of maritime traffic flow in the eastern Mediterranean Sea, and Saudi Arabia serves as a bridge for maritime trade between Asia and Europe. (3) The maritime traffic relations show the characteristics of regionalization; countries in west Asia and the European Mediterranean region are clearly polarized, and competition–synergy relations have become the main form of maritime traffic relations among the countries in the dominant regions. Our results can provide a scientific reference for the coordinated development of regional shipping, improvement of maritime competition, cooperation strategies for countries, and adjustments in the organizational structure of ports along the Maritime Silk Road.

Dynamics of Regional Recycling Economy Development Based on Material Flow Analysis: A Case Study in Shandong Province

2011 ◽  
Vol 347-353 ◽  
pp. 2961-2966
Author(s):  
Dian Ming Geng ◽  
Jia Xiang Liu
Keyword(s):  
Water Supply ◽  
Circular Economy ◽  
Material Flow ◽  
Flow Analysis ◽  
Material Flow Analysis ◽  
Shandong Province ◽  
Utilization Efficiency ◽  
Recycling Economy ◽  
Material Input ◽  
Inputs And Outputs

In order to study the development of regional recycling economy, the material inputs and outputs of the eco-economic system in Shandong Province during the period from 1996 to 2009 were systematically analyzed by the material flow analysis(MFA). The results show that, (1)excluding water, material inputs and outputs rose persistently, but both were lower than the rate of GDP growth. (2)Water supply had a turning point in 2003, from 25.239 billion tons down to 21.934 billion tons, followed by the total annual water supply has been maintained at 220 million tons. At the same time the amount of wastewater emissions is increasing, especially domestic wastewater emissions had faster growth and that increased pressure on the regional water environment;(3) Steady increase in material input intensity, material output intensity presented a first increased and then decreased trend, that showed since Shandong Province proposed the strategic planning to develop circular economy, the development of regional circular economy have improved the material utilization efficiency and made a material reduction in output in the case of material input growth achieved. The rapid increase of material input and output efficiency further illustrated the efficiency of resource comprehensive utilization and waste output have been significantly improved.

SiLK: A Tool Suite for Unsampled Network Flow Analysis at Scale

2014 ◽  
Author(s):  
Mark Thomas ◽  
Leigh Metcalf ◽  
Jonathan Spring ◽  
Paul Krystosek ◽  
Katherine Prevost
Keyword(s):  
Network Flow ◽  
Flow Analysis

Safe water, household income and health challenges in Ugandan homes that harvest rainwater

Water Policy ◽  
2012 ◽  
Vol 14 (6) ◽  
pp. 977-990 ◽  
Author(s):  
David Baguma ◽  
Jamal H. Hashim ◽  
Syed M. Aljunid ◽  
Michael Hauser ◽  
Helmut Jung ◽  
...  
Keyword(s):  
Water Supply ◽  
Health Risks ◽  
Water Shortage ◽  
Information Support ◽  
Household Expenditures ◽  
Safe Water ◽  
Influence Of Water ◽  
Supply Equipment

Having access to a safe water supply is important to improve a person's quality of life. We examine the relationship between the influence of water availability on monthly household expenditures (the dependent variable) and independent variables such as household characteristics, tank size, usage instructions and post-construction guidance, including the management of water-related health risks. The sample consisted of 301 respondents who harvest rainwater in Uganda. A multiple regression analysis was used to analyse the data. The findings show that post-construction guidance and tank size were significant variables. This study suggests the need for a follow-up to improve health after the installation of water supply equipment, i.e., to provide information about water risks, foster reading norms and facilitate the availability and affordability of information sources, e.g., subsidised newspapers and information support devices (computers). Additionally, this study shows the possibility of increased savings due to reduced expenditures on water from vendors and the management of water-related health risks caused by a water shortage, e.g., dehydration. Overall, the study reveals two possible ways to advance policy and health in developing countries: (1) ensuring sufficient post-construction guidance for all water resources; and (2) ensuring a sustainable supply of adequate safe water in households.

The Observation of Rainwater Harvesting Potential in Mahasarakham University (Khamriang Campus)

2013 ◽  
Vol 807-809 ◽  
pp. 1087-1092 ◽  
Author(s):  
Nida Chaimoon
Keyword(s):  
Water Resources ◽  
Water Supply ◽  
Water Conservation ◽  
Rainwater Harvesting ◽  
Flow Analysis ◽  
Treatment Plant ◽  
Drainage System ◽  
Material Flow Analysis ◽  
Sustainable Living ◽  
Water Treatment Cost

Rainwater harvesting from roof is considered as valuable water resources. Material Flow Analysis (MFA) of water in Mahasarakham University (Khamriang Campus) shows that rainwater harvesting from roof can reduce water supply production by 7% and save more than 200,000 Bt/year for water treatment cost. The sensitivity analysis suggests that by 5% water supply conservation and 20% additional rainwater harvesting, MSU could have enough water resources. The rainwater is suitable to be substituted water for gardening due to the convenience to assemble an above ground storage tank or a pond to store harvested rainwater from roof. The current practice of rainwater is collected and discharged into drainage system and treated in wastewater treatment plant. Utilisation of rainwater harvested could reduce wastewater amount that must be treated by 9%. Rainwater harvesting and reuse should be promoted in campus in order to encourage sustainable living and water conservation policy.

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