• 한국산업융합학회 논문집
• /
• 제26권2_2호
• /
• pp.307-313
• /
• 2023

This study conducts the flow analysis on the basis of the impeller RPM of water metering valve. The software used for the flow analysis is STAR-CCM+. In terms of the structure of the metering valve, it has an impeller installed inside, and a metering chamber has inlet and outlet holes. The flow analysis on the water metering valve drew the following conclusions: Regarding the flow field in the valve, the impeller had the highest velocity distribution, and complex flow field was generated in the metering chamber. In particular, since the path between the inlet and outlet holes in the metering chamber and the valve body was narrow, there was a section that had flow field interference. The flow rate and flow coefficient distribution according to the impeller RPM were on the linear increase. Given that, it showed the feature of the valve used for water metering on the basis of the impeller RPM.

• 한국농공학회:학술대회논문집
• /
• 한국농공학회 2005년도 학술발표논문집
• /
• pp.56-60
• /
• 2005

It is necessary to irrigate for agriculture in Korea and agricultural canals play important roles in irrigation. Nowadays gauging water discharge in canals is important because of water shortage in Korea. But It is rare to gauging water discharge in canals. Several water level gauges are installed in agricultural canals through TM/TC. But the abilities of the gauges are insufficient for agricultural water metering. In this situation, we are developing the water discharge metering system which is inexpensive and easy to maintain.

• 한국산업정보학회논문지
• /
• 제22권4호
• /
• pp.11-18
• /
• 2017

본 논문은 소비자에게 공급되는 수돗물의 공급시설(Water Supply Network)에 IoT 기술을 활용하여 소비자의 물 사용량을 원격으로 검침하고, 공급시설의 누수를 줄여서 원가를 절감하는 스마트 물관리(Smart Water Management) 기술의 적용효과를 검증하였다. SWM 실증모형은 수돗물 공급시설에 원격 누수감지센서, 스마트 미터링(Smart Metering), 초소형 멀티센서를 설치하고, 원격에서 운영현황을 실시간으로 감시하고 소비자에게 수돗물 사용량과 수질을 스마트폰 앱으로 제공하였다. 이때, 소비자가 수돗물 사용량 정보를 이용하여 수돗물을 아껴 쓰는지, 수돗물 수질정보를 이용하여 직접 음용하는지를 조사하였다. 특히, 본 연구에서는 SWM을 실증 적용함으로써 공급시설의 유수율 향상, 수돗물 음용률 향상, 소비자 민원 감소, 운영비용 절감, 수돗물 사용량 절감이 달성되는지를 검증하는데 목적이 있다. 또한 수돗물 공급시설의 IoT 센서, 운영자 모니터링 시스템, 이상발생시 탐사복구 솔루션이 융합된 하나의 SWM 모델을 수립하였으며, 관련 기술 개발을 통해 국내 물산업을 육성하고, SWM을 선진수준으로 확산하였다는데 의의가 있다고 하겠다.

• 한국지열·수열에너지학회논문집
• /
• 제15권2호
• /
• pp.10-16
• /
• 2019

In this study, the present regulation of heat metering for the ground source heat pump was investigated. The ground source heat pump has been adopting the heat metering system used in the district heating system for estimating the heating and cooling energy production amount. The accuracy of the present heat metering systems for a water to water ground source heat pump is low, because the system for district heating has a relatively high temperature range comparing with the ground source heat pump operating conditions. Even though the heat amount for the building side should be measured, the heat absorption and extraction amount from or to the ground was measured for the water to air ground source heat pump due to the difficulty of estimating the air side heating and cooling capacity in the present regulation. It is highly recommended to validate the heat metering system to have reliability for the ground source heat pump and develop the system to be applicable water to air ground source heat pump.

• Journal of Biosystems Engineering
• /
• 제34권3호
• /
• pp.140-146
• /
• 2009

The garlic, along with the red pepper, is one of the major seasoning vegetables in Korea. Garlic clove planting is one of the most laborious operations. Labor cost is the main source of high production cost of the garlic. Because of the geometrical uniqueness and irregularity of garlic cloves, mechanization of garlic clove planting is very difficult. To overcome price competition against the imported garlic, however, there has been a need of development of a clove metering device and a planting device for the garlic clove planter. Computer simulation, laboratory tests and field tests were conducted to develop a garlic clove planter. This research was conducted to drop garlic cloves into a soil holes through a drum bucket metering system and a rotary type planting system. Followings are the major achievements from this study. 1. The metering device consisted of a drum, a guide, a bucket and a bucket cover. Opening positions of the metering hopper were evaluated at different positions and trajectories of planting hoppers. The simulation showed that the optimum positions of hopper was -15${\sim}$0 mm in the x direction. 2. When the planter was tested under different soil textures and water contents, the best performances were obtained in a upland field with 29.1% water content and a paddy field with 18.3% water content where single clove metering and missing rate were 88.4% and 1.3%, and 90.7% and 2.0%, respectively.

• 수도
• /
• 통권26호
• /
• pp.26-28
• /
• 1981

이 글은 국제수도협회(IWSA) 주최 국제수도회의 수도미터 및 계량상임위원회(International standing comittee on water meter and water metering)에서 벨기에의 A. Desmed가 발표한 내용을 번역 게재한다.

• 상하수도학회지
• /
• 제24권5호
• /
• pp.495-508
• /
• 2010

The aim of this study is to develop a quantified water loss Index to evaluate and manage leakage scientifically for the reduction of non-revenue water in water distribution systems. For the purpose, unavoidable background leakage suggested from UK water industry and IWA, and allowable water leakage in accord with the concept of allowable water loss are proposed by analyzing the inflow into two study water districts and the short-term water use of each customer in the districts. The study distribution areas are selected among the metered districts with good maintenance of leakage after improvement activities in Nonsan, medium sized city in Korea. Estimation models of allowable leakage are developed by metering and analyzing the minimum night flow at residential and commercial areas in the city. In the results of the investigation, it is estimated that background night flow in residential area was larger than that of commercial area where the types of business shows small water use characteristics. Meanwhile, night flow and background water loss on internal plumbing systems show great differences for each district which is influenced much by the water use characteristics and facilities scale. Based on metering water use data in various districts, leakage management criteria can be established under the consideration of domestic conditions in Korea by analyzing separated real water use and background leakage and it is possible to apply into presentation of optimal leakage level and reasonable time for working activities for leakage reduction.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제16권5호
• /
• pp.1540-1560
• /
• 2022

Latest technological innovation in the development of compact lower power radios has led to the explosion of Internet of Things. With Wi-Fi, Zigbee and other physical layer protocols offering short coverage area there was a need for a RF protocol that had a larger coverage area with low power consumption. LoRa offers Long Range with lower power consumption. LoRa offers point to point and point to multipoint connections. with Single hop communication in place the need for routing protocols are eliminated. LoRa Wide Area Network stack can accommodate thousands of nodes under a single LoRa gateway with a single hop communication between the end nodes and LoRaWAN gateway. This paper takes an experimental approach to analyze the basic physical layer parameters of LoRa and the practical coverage offered by a LoRaWAN under highly dense urban conditions with variable topography. The insights gained from the practical deployment of the LoRaWAN network, and the subsequent performance analysis is used to design a novel public utility monitoring platform. The second half of the papers is designing a robust platform to integrate both existing wired sensor water meters, current and future generation wireless water meters. The Common Automated Metering Platform is designed to integrate both wired sensors and wireless (LoRaWAN and Wi-Fi) supported water meters. This integrated platform reduces the number of nodes under each LoRaWAN gateway and thus improves the scalability of the network. This architecture is currently designed to accommodate one utility application but can be modified to integrate multi-utility applications.

• 상하수도학회지
• /
• 제22권5호
• /
• pp.489-493
• /
• 2008

• 상하수도학회지
• /
• 제28권5호
• /
• pp.509-516
• /
• 2014

This study describes a reasonable planning method for water meter replacement which can minimize the metering under-registration for an increasement of revenue water. The increment analysis of real water usage was used to establish a replacement plan. The meter replacement database collected from K City was used as the basis of this analysis. The database included 964 connections of domestic and non-domestic consumers that had their meter replaced by aging at 2011. The result showed that the corelation between unregistered water volume and water meter age was lower than commonly expected where the current criteria of replacement is only water meter age(8 years) excluding the meters older than 13 years. And in the analysis result of water usage for 8 years, the total amount and increment of water usage had a significant effect on unregistered water volume. However the relation was different tendency as a total volume and slope of increment. In case of total water volume was larger than 10,000, larger than 7,000 and increment of 0.0 ~ -0.3, larger than 6,000 and increment more than -0.3 were analysed to need a replacement because of metering under-registration.