• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.10
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• pp.1720-1725
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• 2008

Because of the continuous increasing of energy consumption, metallic pipelines are widely used to supply services to customers such as gas, oil, water, etc. Most common metallic pipelines are underground and are now frequently being installed in nearby electric power lines. In recent years, buried gas pipeline close to power lines can be subjected to hazardous induction effects, especially during single line to ground faults. because it can cause corrosion and it poses a threat to the safety of workers responsible for maintenance. Accordingly, it is necessary to take into consideration for analysis of induced voltage on gas pipelines in transmission lines. This paper analyzed the induced voltage on the gas pipelines due to the 154kV transmission lines in normal case and in different faulty case conditions using EMTP (Electro-Magnetic Transients Program).

• 한국IT서비스학회:학술대회논문집
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• 2009.11a
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• pp.459-466
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• 2009

USN(Ubiquitous Sensor Network)을 이용한 상수도 관리 시스템은 상수도관로에 설치된 센서들 간에 네트워크망을 구축하여 상수도 관리에 필요한 주요 정보를 실시간으로 수집하고 관리하는 시스템이다. 센서의 종류에 따라서 수질, 유량, 유압, 타공사감지, 누수탐지 등의 정보가 수집되며 관제 센터로 전송되어 데이터베이스에 저장되거나 모니터링 화면에 출력되고 필요한 경우 단문자 서비스를(SMS) 이용하여 관리자에게 통보한다. 본 논문에서는 센서의 설치와 입력된 신호의 처리를 통하여 압력과 타공사감지 및 누수를 탐지하는 방법 및 센서 네트워크를 구성하는 방법을 제안하였고, 남양주시의 상수도관로상에 적용하여 그 성능을 검증하였다[1].

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.65.6-65
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• 2001

The satellite communication has been widely applied in the various fields included the remote monitoring and control system through the technical progress. In the star network that is a type of the satellite communication network, users can easily use an earth station because of the large scale and high power of the hub station. This type has many profits which are flexible of network configuration, and can conveniently and inexpensively supply various services which is used in the data acquisition and distribution by important communication means for construction of information society. Using these profits, the satellite communication system is applied to the unmaned remote operation field for the remote control and monitor of the water treatment plants But, ...

• KCID journal
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• v.17 no.2
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• pp.71-81
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• 2010

Stream Pilot Project, which began in May 2003 and finished in December 2003, was selected to develop effective methods applicable to nature-like streams. Stream restoration projects aim to maintain or increase ecosystem goods and services while protecting downstream and coastal ecosystems. Fields environmental monitoring such as flow discharge and precipitation were conducted along the Idong stream for amount of channel zone change in 2007. This study selected three monitoring positions to measure the water level and discharge of flowing water. A stage-discharge relation is obtained from direct discharge measurements for three stations by fitting an empirical relationship to the data set. Since discharge measures are made only for low flow conditions, a curve of discharge against stage can then be built by fitting these data with a power curve. And this study used data obtained from floodmark checkup as well as HEC-RAS model to analyze the hydrodynamic characteristics of monitoring sites. Reach-averaged hydraulic parameters for the supply reach were calculated from the small area's HEC-RAS model for Idong stream, and a HEC-RAS model used to analyze hydraulics for a period in 2007, after the stream was considered bank stabilization.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.4
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• pp.545-550
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• 2011

Urea intercalated into montmorillonite (MT) exhibits remarkably enhanced N use efficiency, maintaining its fast effectiveness. This study dealt with the release property of urea from metal-urea-clay hybrid with MT (MUCH) under continuous-flow conditions and the cumulative impacts of its successive application on physicochemical properties of soils. Releases of urea were completed within 4 hrs under continuous-flow condition regardless of the types and the leaching solutions. However, urea release property was significantly affected by both the form of fertilizer and the presence of electrolytes in solution. The fast release property of urea from MUCH in continuous-flow condition was not significantly affected by soil properties such as soil pH and soil texture. In addition, its successive application did not lead to any noticeable change in soil physicochemical properties, water stable aggregate rate, water holding capacity and cation exchange capacity in both sandy loam and clay loam soils. Therefore, this study strongly supported that urea intercalated into MT could be applied as fast-effective N fertilizer, in particular for additional N supply.

• Journal of agriculture & life science
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• v.45 no.1
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• pp.1-7
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• 2011

An experiment was conducted to test different heights of drainage level sensors in an irrigation management system for perlite bag culture of cucumber and paprika. The sensors were placed at 4, 8, 12, and 16 mm from the bottom of the container. Both cucumber and paprika did not show any significant difference in growth and yield among the treatments. However, placing the sensor at 4 mm seemed to be the best in order to prevent over-supply of water at the beginning of the day.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.12
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• pp.6143-6150
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• 2012

The current society, namely information society is now moving to a specific topic which is SMART. In this sense, recently a variety of social areas including communications and SOC domains are moving fast to this topic. In Korea, The electric power area has been doing a pioneering job relatively successfully and the water supply area is just now taking the first step. The purpose of this research is to develop a technical Framework for Smart Water Grid Service. Related researches has been studied and the 4 constituting technical element areas were defined first. For each of the four areas, a framework modeling was fulfilled and as a result, a TRM(Technical Road Map) was suggested for each of the area. Finally, an Enterprise TRM covering all of the 4 areas was described. Furthermore, the currently suggested Framework model was compared to a related model and it was found that the integration of the models is desirable to wholly cover from Macro to Micro level applications and services. It is expected that the current approach contribute, more or less, to the smart implementation in the areas of water management.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1286-1294
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• 2011

This paper reviews the future directions and perspectives on the soil environmental researches in the 21 century. Previously, the principal emphasis of soil environmental researches had put on the enhancement of food and fiber productions. Beside the basic function of soil, however, the societal needs on soil resources in the 21st century have demands for several environmental and social challenges, occurring regionally or globally. Typical global issues with which soil science should deal include food security with increasing agronomic production to meet the exploding world population growth, adaptation and mitigation of climate change, increase of the carbon sequestration, supply of the biomass and bioenergy, securing the water resource and quality, protection of environmental pollution, enhancing the biodiversity and ecosystem health, and developing the sustainable farming/cropping system that improve the use efficiency of water and agricultural resources. These challenges can be solved through the sustainable crop production intensification (SCPI) or plant welfare concept in which soil plays a key role in solving the abovementioned global issues. Through implementation of either concept, soil science can fulfill the goal of the modern agriculture which is the sustainable production of crops while maintaining or enhancing the ecosystem function, quality and health. Therefore, directions of the future soil environmental researches should lie on valuing soil as an ecosystem services, translating research across both temporal and spatial scales, sharing and using data already available for other purposes, incorporating existing and new technologies from other disciplines, collaborating across discipline, and translating soil research into information for stakeholders and end users. Through the outcomes of these approaches, soil can enhance the productivity from the same confined land, increase profitability, conserve natural resource, reduce the negative impact on environment, enhance human nutrition and health, and enhance natural capital and the flow of ecosystem services. Soil is the central dogma, final frontier and new engine for the era of sustainability development in the $21^{st}$ century and thus soil environmental researches should be carried according to this main theme.

• Korean Journal of Agricultural and Forest Meteorology
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• v.16 no.4
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• pp.359-367
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• 2014

Drought index can be used to implement an early warning system for drought and to operate a drought monitoring service. In this study, an approach was examined to determine agricultural drought index (ADI) at high spatial resolution, e.g., 270 m. The value of ADI was calculated based on soil water balance between supply and demand of water. Water supply is calculated by the cumulative effective precipitation with the application of the weight to the precipitation from two months ago. Water demand is derived from the actual evapotranspiration, which was calculated applying a crop coefficient to the reference evapotranspiration. The amount of surface runoff on a given soil type was also used to calculate soil residual moisture. Presence of drought was determined based on the probability distribution in the given area. In order to assess the reliability of this index, the amount of residual moisture, which represents severity of drought, was compared with measurements of soil moisture at three experimental between July 2012 and December 2013. As a result, the ADI had greater correlation with measured soil moisture compared with the standardized precipitation index, which suggested that the ADI would be useful for drought warning services.

• Korean journal of applied entomology
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• v.48 no.4
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• pp.485-491
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• 2009

This study was conducted to investigate the fruit damage according to the number of released stink bugs and date of adult introduced on non-astringent persimmon. The fruit damage differed significantly by the number, date, and the source of feed for Riptortus clavatus. Damages on the fruits appeared when five bugs were released to mother branches bearing fruits. Damages to the fruits was heavy in the case that bugs were introduced in September and October, compared with in June, July and August. Persimmon fruit damage was influenced significantly by the available sources to R. clavatus, persimmon fruit alone or additional supply of kidney bean (Phaseolus vulgaris) and water. Characteristic damage symptoms by R. clavatus showed only scars on the fruit skin, without fruit dropping. Halyomorpha halys (=mista) showed significantly higher fruit damage when they were released in July, August, and September compared with other periods. Number of H. halys to the fruit also showed significant differences in fruit damages. Five H. halys in July showed 100% damaged fruits. The fruit damage by Plautia stali was not significantly different according to dates of introduction but the number of insects gave significant differences in the fruit damage ratio at the level of 1, 3, 5 bugs introduced to the mother branche bearing friuts. The damage symptoms by P. stali was fruit dropping in July and August but from September damaged fruits were found in the branches.