• 한국농공학회논문집
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• 제51권6호
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• pp.91-96
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• 2009

This study describes a zero discharge and reuse system developed for rural areas. The purpose of the system is decontamination of used irrigation water for down-stream usage and reuse of wastewater in rural villages for preventing water shortage problem expected to happen in near future. The system consists of anoxic, FES (Ferrous Electricity System), Oxic, Cralifier processes. The main feature of the system is to remove phosphorous by using Fe-ionizing module. Indoor experiments were undertaken with a trial product of the system to test its performance. The removal capacities of T-P, T-N, and BOD were examined. Also the proper time for the replacement of iron plate module was tested as well as the efficiency of T-P removal rate based on the usage of an automatic washing system for the iron plate. As results, the system showed very good water purification performances through obtaining the results of over 90% removal rates from T-P, BOD, and 67% from T-N. The proper time period for replacement of iron plate was maximum 2 years, and also efficiency of T-P removal rate found to be greatly influenced by the usage of an automatic washing system from the test.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.229-236
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• 2002

In this paper, a new novel technique of seismic survey is introduced to estimate the continuity of inclined pits filled with water, It was assumed that the pits would be connected to an abandoned railway tunnel that might be constructed in the past. Thus, detection of pit end was needed for the design of a new highway tunnel(Yukshimreong tunnel) that was likely to be met with a pit. In the beginning of exploration, no reliable, cost effective method was available. Hence, focus of interest moved toward the high impedance contrast(reflection coefficient k∼0.8) between water and rock. In this special model of sequence rock-water-rock, total reflection occurs and the seismic energy, when it is generated in the pit water, is nearly confined to the pit so that seismic waves can propagate much further within the pit. As a matter of convenience, this is called“tunnel channel wave”. With these considerations in mind, seismic detonator(2g) was used as a source at the entrance of pit, whereas hydrophone chain(hydrophone interval=1m) was placed on the bottom of pit. With this appropriate source-receiver arrangement, desirable down-going and up-going waves could be observed that will help conform the continuity of pits. After about one year, it was ascertained that the inclined pit of interest was just nearby crossed with the newly excavated tunnel, as it was predicted.

• 한국식품저장유통학회지
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• 제11권2호
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• pp.154-159
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• 2004

캔음료용 건강미숫가루를 개발하기 위하여 쌀, 보리 및 콩을 이용하여 기본미숫가루용액을 만든 후 몇 종의 한약재를 선발하여 적정 혼합비율로 혼합 추출, 첨가하여 건강미숫가루용액을 제조하였다. 이때 기본미숫가루용액으로 적당한 재료의 혼합은 물 100mL에 쌀, 보리 및 콩을 각각 5 g씩 혼합한 것이 가장 물성이 좋았다. 건강미숫가루용액 제조를 위하여 첨가한 한약재의 추출물은 맥문동 50, 오미자 15, 인삼 10, 대추 25의 비율로 혼합 후 10배 량의 물을 가하여 75$^{\circ}C$에서 36시간 처리하여 얻었으며 기본미숫가루용액 80에 혼합한 한약재 추출물 20의 비율로 혼합한 것이 기본미숫가루용액보다 기호도가 높았다. 건강미숫가루용액의 장기 저장을 위하여 가압살균처리를 함으로써 물성이 걸쭉한 형태로 변하므로서 살균처리시의 건강미숫가루는 배합비율을 기본미숫가루 60, 한약재혼합추출물 30, 물 10의 비율로 달리할 필요가 있었으나 기호도는 살균처리하지 않은 것보다 낮은 경향이었다. 살균처리하지 않은 건강미숫가루용액은 첨가한 한약재추출물에 의하여 방부 효과를 나타내었으며 살균처리하지 않은 상태로 제품화할 경우 $25^{\circ}C$에서 6일간 저장이 가능하였다.

• 한국치위생학회지
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• 제9권1호
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• pp.181-192
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• 2009

The purpose of this study was to examine college students' perception on the water fluoridation program and to analyze the similarities and differences in the perceptions of those to provide the basic data for program development and policy planning, the survey with convenience sampling was carried out to 592 college students and then obtained that results. 1. The question about whether you know what is the water fluoridation program got the answers 'know well 5.7%', 'know a little 32.6%', but the ratio of correctly recognizing college students about the program for the purpose of preventing cavities is 19.6% so it was concluded that the accurate education about the definition and the protective of the water fluoridation program is urgent. 2. The rate of consent about claims that the water fluoridation program is a public health program similar to vaccination in the receptivity of the pros for the program is the highest with boy students(64.4%), girl students(75.2%) and therefore it is concluded that it will utilize for the water fluoridation business publicity. 3. Stronger concern for oral health led to the greatest impact on the receptivity of the pros for the water fluoridation program. 4. Most students answered that the time of the water fluoridation operation have to operate gradually and the respondents are 349 students(59%). Therefore it is concluded that the water fluoridation should be taken place in north Jeolla province.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 D
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• pp.778-780
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• 1997

This study considers a hydro power energy operation management and planning problem in KEPCO power systems for efficient use of hydro resources. A database is developed to provide with a convenience to hydro Power operation management and Planning by studying of the hydro resourse characteristics of Korea. The data is obtained in the operation history from 7 years ago and by considering the hydro facility planning to 2010 year. Also a computer program is developed to decide the monthly required volume of water and the water level of a dam in the Han river using the database.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2001년도 학술발표회 발표논문집
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• pp.421-425
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• 2001

Among the many parameters describing water quality, total nitrogen content(TN) is regarded as important one in relation to water quality management of the waterbodies for its role in eutrophication process. This study evaluated for accuracy, convenience and promptness of nitrogen analysis methods : (1)UV spectrophotometric method, (2)summation method, (3)cadmium reduction method. And, the detection limit of each method was calculated using EPA method. The UV spectrophotometric method after oxidation appears to be more convenient and accurate in determination of the TN contents than the summation method and cadmium reduction method. The summation method is necessary to separate determinations of the organic nitrogen, ammonia, nitrite, and nitrate. And, because summation method has many other methods for each contents, it can be detected for wide range of concentration.

• 물과 미래
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• 제15권4호
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• pp.39-44
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• 1982

본 연구는 수면변화의 전파특성을 이용한 4점법(four-point method of characteristics)의 선형화이론을 개수로의 불정류해석에 적용하는 문제와 관련하여, 직사각형 만입에서 본 해석모형에 대한 1차원 정진동 수치 검정실험을 실시하였고, 2차원 불정류의 해석에 있어서 안정성(stability) 문제에 대하여 검토하였다. 본 해석모형은 수위변화가 수심에 비해 충분히 작은 흐름의 경우에 효과적으로 간편하게 사용할 수 있음을 알 수 있었다.

• Preventive Nutrition and Food Science
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• 제18권1호
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• pp.60-66
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• 2013

The whole saltwort plant (Salicornia herbacea) was micronized to develop the table salt substitute. The micronized powder was mixed with distilled water and made into a spherical granule by using the fluid-bed coater (SGMPDW). The SGMPDW had superior flowability to powder; however, it had low dispersibility. To increase the dispersibility of SGMPDW, the micronized powder was mixed with the solution, which contained various soluble solid contents of saltwort aqueous extract (SAE), and made into a spherical granule (SGMPSAE). The SGMPSAE prepared with the higher percentages of solid content of SAE showed improved dispersibility in water and an increase in salty taste. The SGMPSAE prepared with 10% SAE was shown to possess the best physicochemical properties and its relative saltiness compared to NaCl (0.39). In conclusion, SGMPSAEs can be used as a table salt substitute and a functional food material with enhanced absorptivity and convenience.

• Journal of the Korean Wood Science and Technology
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• 제20권4호
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• pp.21-30
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• 1992

An activation energy equation for moisture diffusion in wood was developed with an assumption that activation energy is directly proportional to wood specific gravity. Theoretical activation energies obtained from the activation energy equation were revealed to be always lower than actual activation energies, which implies that activation energy isn't affected only by wood specific gravity. The other affecting factors are possibly anatomical structures of wood which determine a ratio of vapor diffusion to bound water diffusion in wood. For the convenience of estimating actual activation energy by using the activation energy equation, thirteen kinds of species were categorized into three groups according to their anatomical structures.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2003년도 International Symposium on Clean Environment
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• pp.135-138
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• 2003

Based on solid phase extraction, gas chromatography and mass spectrometry procedure for determining phenol and its derivatives in natural water was presented. In solid phase extraction, three types of techniques using solid phase adsorption material were treated with acid and salt, and converted second portion of acetyl derivatives. Under the these condition, extraction efficiency and detection ability dependent on extraction methods were discussed. Obtained results using optimized solid phase extraction techniques showed more convenience, simplifier and lower cost than the conventional analytical methods with holding wide dynamic range and lower detection limits.