엔트로피 이론과 유전자 알고리즘을 결합한 상수관망의 최적 압력 계측위치 결정

장동일,하금률,전환돈,강기훈 대한상하수도학회 2012 상하수도학회지 Vol.26 No.1

The purpose of water distribution system is supplying water to users by maintaining appropriate pressure and water quality. For efficient monitoring of the water distribution system, determination of optimal locations for pressure monitoring is essential. In this study, entropy theory was applied to determine the optimal locations for pressure monitoring. The entropy which is defined as the amount of information was calculated from the pressure change due to the variation of demand reflected the abnormal conditions at nodes, and the emitter function (fire hydrant) was used to reproduce actual pressure change pattern in EPANET. The optimal combination of monitoring points for pressure detection was determined by selecting the nodes receiving maximum information from other nodes using genetic algorithm. The Ozger’s and a real network were evaluated using the proposed model. From the results, it was found that the entropy theory can provide general guideline to select the locations of pressure sensors installation for optimal design and monitoring of the water distribution systems. During decision-making phase, optimal combination of monitoring points can be selected by comparing total amount of information at each point especially when there are some constraints of installation such as limitation of available budget. The purpose of water distribution system is supplying water to users by maintaining appropriate pressure and water quality. For efficient monitoring of the water distribution system, determination of optimal locations for pressure monitoring is essential. In this study, entropy theory was applied to determine the optimal locations for pressure monitoring. The entropy which is defined as the amount of information was calculated from the pressure change due to the variation of demand reflected the abnormal conditions at nodes, and the emitter function (fire hydrant) was used to reproduce actual pressure change pattern in EPANET. The optimal combination of monitoring points for pressure detection was determined by selecting the nodes receiving maximum information from other nodes using genetic algorithm. The Ozger’s and a real network were evaluated using the proposed model. From the results, it was found that the entropy theory can provide general guideline to select the locations of pressure sensors installation for optimal design and monitoring of the water distribution systems. During decision-making phase, optimal combination of monitoring points can be selected by comparing total amount of information at each point especially when there are some constraints of installation such as limitation of available budget.

라이프라인의 Smart-Pipe 시스템 도입을 위한 이익정량화 방안

전환돈,김중훈,조문수,백천우,유도근 한국방재학회 2008 한국방재학회논문집 Vol.08 No.04

As the water distribution system which is one of the critical lifeline system is deteriorated and pipe failures occur frequently, the more efficient pipe monitoring system becomes a critical issue in the water industry. One of the pipe monitoring systems is called "Smart-pipe" which is permanent, comprehensive and an automated SIM (Structural Integrity Monitoring) system and has superiorities to existing monitoring system. To implement a smart-pipe on a water distribution system, assessment of its indirect benefit obtaining from smart-pipe such as the ratio of preventing water main failures must be preceded. However, only some researches on this field have been performed. In this paper, the concept of smart-pipe is compared with the current monitoring systems for a water distribution system, and a method to quantify its benefit using the inconvenient time for customers in man-hours is suggested. The suggested method was applied to a real water distribution system to estimate its applicability and benefit. 상수관망의 노후화에 따른 잦은 파괴로 인해 보다 효율적인 상수관망 모니터링시스템 구축이 중요한 문제가 되었다. 상수관망의 모니터링 시스템의 하나인 smart-pipe는 영구적이며 포괄적인 자동화된 형태의 SIM 시스템으로 기존의 모니터링 시스템에 비해 많은 장점을 가지고 있다. Smart-pipe를 도입하기 위해서는 상수관 파괴를 미리 예측하여 갑작스러운 상수관 파괴를 막는 것과 같이 smart-pipe 설치를 통해 발생하는 간접적 이익의 정량화가 우선되어야 한다. 그러나 이와 관련된 연구는 국내외적으로 매우 미비한 실정이다. 본 연구에서는 smart-pipe의 개념을 기존 상수관 모니터링 시스템과 비교하였으며 smart-pipe 설치에 따른 이익을 수용가불편시간으로 정량화하는 방안을 제시하였다. 제안된 방법을 고양시의 상수관망에 적용하여 적용성을 검증하였으며, smart-pipe시스템의 도입을 위한 기초자료로 활용될 수 있을 것으로 판단되었다.

상수도관망의 피해율 저감을 위한 가압장 최적운영기법 개발

권혁재 한국수자원학회 2019 한국수자원학회논문집 Vol.52 No.5

In this study, the optimum pump operation technique is suggested to decrease the damage rate of water distribution system. Pump operation system was developed to achieve the effective pump operation. Pressure sensors which can communicate with pumps are installed at the end of water distribution system. Pump operation system can control the pressure of water pump according to data sent from the pressure sensors. Therefore, water distribution system can reduce the pressure and maintain enough pressure which can supply the demand of water users. For proving effectiveness of new system, reliability model was introduced to compare the results of damage rates between the maintaining high pressure and selective pressure in water pump. Unsteady analysis was conducted with several scenarios. And the results were used to calculate the probability of pipe breakage. From the results, it was found that new pump operation system can reduce the energy usage and probability of pipe breakage by applying to pumps. 본 연구에서는 상수도관망의 피해율 저감을 위한 최적의 펌프운영기법을 제안하였다. 펌프운영시스템은 효과적인 펌프운영을 위하여 개발되었다. 이를 위해 펌프와 소통할 수 있는 압력센서가 상수도관망의 관말단부에 설치되었다. 펌프운영시스템은 관말단의 센서로 부터 수신된 데이터를 통하여 펌프를 제어하게 된다. 따라서 펌프운영시스템은 관말단부에 충분한 유량을 전달할 수 있는 압력을 유지할 수 있고 불필요한 압력을 줄일 수 있다. 펌프운영시스템의 효과를 입증하기 위해 신뢰성해석모형이 사용되었고 기존의 펌프운영시스템과 새로운 펌프운영시스템의 운영결과를 통하여 상수도관의 파괴확률을 정량적으로 비교하였다. 이를 위해서 부정류해석을 수행하였고 그 결과는 파괴확률을 산정하는데 사용되었다. 그 결과, 새로 제시된 펌프운영시스템은 상수도관의 파괴확률을 현저히 낮출 수 있음을 확인할 수 있었다.

상수관망 에너지 모의를 위한 정량화 분석기법 개발

최두용,김상현,김경필 한국수자원학회 2022 한국수자원학회논문집 Vol.55 No.-

Efforts for reducing greenhouse gas emission coping with climate change have also been performed in the field of water and wastewater works. In particular, the technical development for reducing energy has been applied in operating water distribution system. The reduction of energy in water distribution system can be achieved by reducing structural loss induced by topographic variation and operational loss induced by leakage and friction. However, both analytical and numerical approaches for analyzing energy budget of water distribution system has been challengeable because energy components are affected by the complex interaction of affecting factors. This research drew mathematical equations for 5 types of state (hypothetical, ideal, leak-included ideal, leak-excluded real, and real), which depend on the assumptions of topographic variation, leakage, and friction. Furthermore, the derived equations are schematically illustrated and applied into simple water network. The suggested method makes water utilities quantify, classify, and evaluate the energy of water distribution system. 기후변화에 대처하기 위한 온실가스 저감 노력은 상하수도 분야에서도 활발하게 진행되어 왔으며, 특히, 상수도 생산 및 공급과정에서 많은 에너지를 소비하는 상수관망의 에너지를 절감하기 위한 많은 기술개발이 이루어져왔다. 상수관망의 에너지 절감은 지형의 기복으로 발생되는 구조적 손실의 저감과 누수 및 마찰손실로 인한 운영 상 손실의 효율화를 통해 성취될 수 있음에도 실제 상수관망의 에너지 수지를 분석하는 단계에서 이들 인자들 상호간의 복합적 작용으로 인해 해석적인 접근뿐 아니라 수치모형을 이용한 모의에서도 한계를 노출하여 왔다. 본 연구에서는 지형의 기복, 누수 및 마찰손실의 유무에 따라 변화하는 유량, 압력수두 및 에너지를 5가지의 상수관망 상태(가설적 상태, 이상적 상태, 누수가 포함된 이상적 상태, 누수가 배제된 실제 상태, 실제 상태)에 대하여 수리 물리적 방정식을 도출하고, 이를 단순한 형태의 상수관망에 적용함으로서 에너지의 정량적 분석 및 분류, 각종 에너지 수지 구성요소별 분석과 이를 이용한 상수도 시스템의 에너지 진단이 가능하도록 하였다.

부정류 흐름에서 상수관망 수질해석을 위한 동역학적 모형의 개발

최두용,조원철,김도환,배철호 대한상하수도학회 2012 상하수도학회지 Vol.26 No.5

A dynamic water quality model is presented in order to simulate water quality under slowly varying flow conditions over time. To improve numerical accuracy, the proposed model uses a lumped system approach instead of extended period simulation, unlike the other available models. This approach can achieve computational efficiency by assuming liquid and pipe walls to be rigid, unlike the method of characteristics, which has been successfully implemented in rapidly varying flows. The discrete volume method is applied to resolve the advection and reaction terms of the transport equation for water quality constituents in pipes. Numerical applications are implemented to the pipe network examples under steady and unsteady conditions as well as hydraulic and water quality simulations. The numerical results are compared with EPANET2, which is a widely used simulation model for a water distribution system. The model results are in good agreement with EPANET2 for steady-state simulation. However, the hydraulic simulation results under unsteady flows differ from those of EPANET2, which causes a deviation in water quality prediction. The proposed model is expected to be a component of an integrated operation model for a water distribution system if it is combined with a computational model for rapidly varying flows to estimate leakage, pipe roughness, and intensive water quality.

투석용수 분배배관의 유기오염물질의 관찰 및 소독

노인혜,정찬호,김도훈,이진석 慶星大學校 環境問題硏究所 2002 環境硏報 Vol.12 No.1

It is very important to manage water purification system(included Reverse Osmasis unit) and distribution system, such as connecting value and pipe between water purification system and artificial kidney machine, since dialysis patient were directly exposed to Ro water to be produced and transfered by them. We can see that organic contaminates, such as bacteria and endotoxin etc., increased as RO water transferred through distribution system. In order to remove them, we taken place to disinfect water purification system and distribution system with peracetic acid, then could observe to decrease count(mass) of them.

다목적 유전 알고리즘을 이용한 상수관망의 최적 설계 연구

최예지,최연규,김권석,장동우 (사)위기관리이론과실천 2023 Crisisonomy Vol.19 No.2

Water supply system that provide safe water to customers should be designed to reduce construction cost and management cost. Pipe diameter is a key aspect of water distribution system since it affects design cost and friction loss. This study applied multi-objective optimization algorithm coupled with EPANET hydraulic solver for minimizing design cost and friction loss energy to water distribution system. Non-dominated sorting genetic algorithm (NSGA-Ⅱ) was used as an optimization technique. The hydraulic results such as head loss and flow in the pipeline were obtained from EPANET program. The test bed was the Cheongna water distribution system in Incheon, Korea. The findings in this study provided Pareto front of minimizing design cost and friction loss energy with simultaneously satisfying the water demand and hydraulic pressure. This study suggests that NSGA-Ⅱ can be used to design optimal water distribution system that satisfy the multi-objective options. 안정적인 수돗물 공급을 목적으로 하는 상수도 시설은 설계비용과 에너지 비용 등 총 비용을 저감할수 있도록 계획되어야 한다. 상수관망 설계 시 관경에 따라 설계비용이 달라지고 마찰 손실 에너지가달라지기 때문에 적절한 관경을 결정하는 것이 효과적인 관망 관리에 도움이 된다. 본 연구에서는 설계비용의 최소화와 마찰 손실 에너지의 최소화를 목적으로 하는 다목적 최적화 연구를 수행하기 위해 비지배정렬 유전자 알고리즘(NSGA-Ⅱ)과 상수관망 프로그램인 EPANET을 연계하여 적용하였다. 대상지역은인천시 청라지역 3개의 동으로 하였고, 마찰 손실 에너지를 산출하기 위한 관 내의 유량과 마찰 손실수두는 EPANET 모델 결과를 활용하였다. 연구를 통하여 대상지역 상수관망 내 수요량과 압력을 충족시키면서 설계비용과 마찰 손실 에너지의 파레토 프런트를 구성하였다. 또한, 비지배 정렬 유전자를 이용하여 두 목적함수를 만족시키는 관망의 최적 설계 연구가 가능하다는 것을 제시하였다.

Application of Self-adaptive Vision-Correction Algorithm for Water-Distribution Problem

이의훈 대한토목학회 2021 KSCE Journal of Civil Engineering Vol.25 No.3

Water is one of the essential elements in human life, and the water-distribution system is an important infrastructure that distributes water to the people. The design of the water-distribution system was done manually in the past, but recently, it was conducted by applying optimization algorithms. Various optimization algorithms were developed for the optimal design of the water-distribution system, but there was a disadvantage to perform sensitivity analysis for parameter estimation manually. A vision-correction algorithm (VCA) was developed to emulate the conventional manual vision-correction procedure, and it exhibited a good performance in many mathematical benchmark and civil engineering problems. However, the VCA has limited usefulness because of its large number of parameters, many of which require estimation. In this study, a self-adaptive VCA (SAVCA) was developed to overcome these shortcomings by modifying the parameters of the VCA to be self-adaptive or fixed. The Balerma network — a water-distribution system — was selected as a civil engineering problem. The results of SAVCA were better than those of other methods for the design of Balerma network. The SAVCA exhibited good usability and performance and can be applied to various fields in civil engineering including the water-distribution system.

배·급수 시스템에서 부식방지제의 적용 평가 연구

우달식,문정기,구성은,최종헌,김주환,문광순 대한상하수도학회 2003 상하수도학회지 Vol.17 No.5

This study evaluated the effect of the corrosion inhibitors on the corrosion control performance in drinking water distribution system. A phosphate-zinc based inhibitor formulated was for the efficient corrosion control in drinking water distribution system. In a continuous-circulation test, 99% reduction in corrosion rate was achieved. The optimum concentration of the corrosion inhibitor was found to be 2.2㎎ PO₄/L. The effect of the corrosion inhibitor was significant for the pipes of carbon steel, galvanized steel and copper, but less for that of stainless steel. The corrosion inhibitor can be an effective cure for corrosion and red water problems by prevention the old pipes from further corrosion. Tap water in Mokpo and Kwangyang were more corrosive than the water in the rest of 4 other regions(Seoul, Pohang, Pusan, Puyeo). Tap water in Pusan was high in various ionic concentrations in general. The corrosion inhibitor reduced the corrosion rate by 76-94%, depending on the origin of the tap water.

배급수관망에서의 누수복원량 산정방법

진샘물,구자용,김경필 대한상하수도학회 2019 상하수도학회지 Vol.33 No.4

Waterworks facilities inevitably experience some amount of leakage even if there is a lot of investment or state-of-the-art technology that is applied such as DMA(District Metered Area) system construction, leakage detection, repair, pipe rehabilitation, etc. The primary reason is the leakage is naturally restored over time. In the UK, this restoration characteristic is defined as NRR(Natural rate of rise of leakage) and used to decision making for prioritizing active leakage control of DMAs. However, this restoration characteristic is well recognized, but researches on NRR in the water distribution system are insufficient in Korea. In this study, the estimation method of NRR was developed suitable for applicating in Korea considering of SCADA data, water infrastructure, and water usage patterns by modification of the UK's NRR method. The proposed method was applied to 9 DMAs and verified it's applicability by comparing with the other water loss performance indicators. It is expected that the proposed method can be used to support decision making for sustainable NRW(Nor-revenue water) management in the water distribution system.