• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.2
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• pp.175-179
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• 1999

Processing conditions for dried condiments with oyster, pen shell and cockle shell were investigated. The enzymatic hydrolysis for 3 hours was more profitable than hydrothermal extraction to develop flavoring matters from oyster, pen shell and cockle shell. As a result of omission tests, nucleotides were predominated in the taste compounds of shellfish hydrolysates rather than free amino acids, and the contribution of nucleotides and free amino acids to the taste of shellfish hydrolysates was remarkable. The major flavoring components of shellfish hydrolysates were free amino acids and oligopeptides below 500 dalton. When shellfish hydrolysates were separated with membrane (molecular weight cutoff 500 dalton) for recovering flayer, recovering yields of amino type nitrogen were $92.1\~92.8\%$. Moisture contents of dried shellfish condiments prepared with pretense hydrolyzed oyster, pen shell and cockle shell were $3.5\%,\;3.8\%$ and $3.7\%$, respectively. Contents of total nitrogen were $69.4\%,\;78.8\%$ and $74.2\%$, and those of amino nitrogen were $45.5\%,\;48.9\%$ and $45.4\%$, respectively. Drying yield, solubility and absorption rates at Aw 0.88 were $11.7\%,\;78.4\%$ and $6.8\%$ in oyster, $8.2\%,\;73.6\%$ and $6.1\%$ in pen shell, $9.8\%,\;76.9\%$ and $6.6\%$ in cockle shell, respectively.

• Journal of the Korean Chemical Society
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• v.37 no.3
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• pp.327-333
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• 1993

A method was developed for the determination of trace elements in seawater by precipitate flotation preconcentration and subsequent flame atomic absorption detection. In order to quantitatively coprecipitate trace ions such as Cd(II), CuI(II), Fe(III), Mn(II), Pb(II) and Pd(II), 2.0 ml of 1.0M cerium(III) solution was added to 1.0l of seawater and the pH was adjusted to 9.5 with 5.0 M sodium hydroxide solution while stirring with a magnetic stirrer. The precipitate was floated with the aid of surfactant solution (1.0 ml of 0.3% sodium oleate) by bubbling nitrogen gas through a porous (No. 4) fritted glass disk. The floats was collected in a small Erlenmeyer flask by suction. The washed precipitate was dissolved in 8.0 M nitric acid and marked with deionized water in the volumetric flask of 10.0 ml. The analyte was determined by measuring the atomic absorbances in 100-fold concentrated solution. Above all analytes in Kangnung (East Sea) and Kanghwado (West Sea) sea waters were found to be under the detection limit of this method. The recoveries of over 92% for all analytes spiked into seawater samples showed that this method was applicable to the analysis of real seawater.

• The Journal of the Acoustical Society of Korea
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• v.20 no.2
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• pp.77-85
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• 2001

This paper proposes a method of time-scale modification of polyphonic audio signals based on a sinusoidal model. The signals are modeled with sinusoidal component and noise component. A multiresolution filter bank is designed which splits the input signal into six octave-spaced subbands without aliasing and sinusoidal modeling is applied to each subband signal. To alleviate smearing of transients in time-scale modification a dynamic segmentation method is applied to subbands which determines the analysis-synthesis frame size adaptively to fit time-frequency characteristics of the subband signal. For extracting sinusoidal components and calculating their parameters matching pursuit algorithm is applied to each analysis frame of subband signal. In accordance with spectrum analysis a psychoacoustic model implementing the effect of frequency masking is incorporated with matching pursuit to provide a resonable stop condition of iteration and reduce the number of sinusoids. The noise component obtained by subtracting the synthesized signal with sinusoidal components from the original signal is modeled by line-segment model of short time spectrum envelope. For various polyphonic audio signals the result of simulation shows suggested sinusoidal modeling can synthesize original signal without loss of perceptual quality and do more robust and high quality time-scale modification for large scale factor because of representing transients without any perceptual loss.

• Journal of the Korean Vacuum Society
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• v.21 no.4
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• pp.199-204
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• 2012

$SF_6$ gas is widely used for dry etching process of semiconductor and display fabrication process. But $SF_6$ gas is considered for typical greenhouse gas for global warming. So it is necessary to research relating to $SF_6$ alternatives reducing greenhouse effect in semiconductor and display. $C_3F_6$ gas is one of the promising candidates for it. We studied about etch characteristics by performing Reactive Ion Etching process of dry etching and reduced gas element exhausted on etching process using absorbent Zeolite 5A. $Si_3N_4$ thin film was deposited to 500 nm with Plasma Enhanced Chemical Vapor Deposition and we performed Reactive Ion Etching process after patterning through photolithography process. It was observed that the etch rate and the etched surface of $Si_3N_4$ thin film with Scanning Electron Microscope pictures. And we measured and compared the exhausted gas before and after the absorbent using Gas Chromatograph-Mass Spectrophotometry.

• The Korean Journal of Ecology
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• v.27 no.6 s.122
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• pp.375-381
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• 2004

We investigate the biological treatment of processed-leachate from SUDOKWON landfill site in Korea by the reed (Phragmites australis)-bed with a continuous flow system. The reed individuals showing superior growth in processed-leachate experiment were selected among the reeds of thirteen natural habitats by means of the comparisons between the removal rates of nutrient salts, eco-physiological responses and growth. The reed-beds (combination of the reed individuals showing superior growth with helper microorganisms) were continuously supplied with processed-leachate. We monitored the effluents that passing through the reed-beds during the experiment period. After five weeks, analysis results of effluent from each reed-bed were as follows; chromaticity, total nitrogen, total phosphorus, biological oxygen demand, chemical oxygen demand, total dissolved solid and salinity decreased $29.5{\sim}36.9\%,\;49.4{\sim}67.2\%,\;42.1{\sim}94.6\%,\;74.5{\sim}88.8\%,\;15.6{\sim}20.8\%,\;17.5{\sim}35.4\%\;and\;15.3{\sim}34.7\%$, respectively. These results represented the substantial improvement of water-quality after passing through reed-bed in a continuous flow system.

• Journal of Energy Engineering
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• v.24 no.1
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• pp.32-41
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• 2015

The Metropolitan Area Green Heat Project (MAGHP), which collects unused heat gathered from power plants, steel works, landfills in western Metropolitan area and distribute it to integrated energy business (IEB) companies, is proposed for the purpose of enhancing energy efficiency and providing low-price heat for IEB companies. Therefore, in order to decide on whether to initiate the MAGHP, the economic feasibility analysis of the project is widely demanded. This paper attempts to consider and measure four economic benefits: heat supply benefit, production cost reduction benefit, greenhouse gas mitigation benefit, and air quality improvement benefit. In addition, the paper tries to conduct the economic feasibility analysis. The project requires three-year investment and thirty-year operation. Three important findings emerge from the analysis. First, its net present value is computed to be 1,269 billion won and more than zero. Second, its benefit/cost ratio is calculated to be 1.72 and bigger than 1.0. Third, its internal rate of return is estimated to be 24.26% and larger than the social rate of return, 5.5%. In conclusion, the MAGHP is socially profitable and should be conducted immediately.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.263-268
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• 2002

본 연구는 고추분쇄용 세라믹 롤 분쇄기를 이용하여 고춧가루 생산시, 분쇄효율을 향상시키고자 기존의 롤 분쇄속도 40rpm(0.352m/s)에서 80rpm(0.704%)으로 증가시키고, 기존의 롤 회전비 2:1에서 5:1로 증가시켜 고추분쇄시 전단력 증가로 분쇄능을 향상시켰고, 연구 내용의 주요 결과를 요약하면 다음과 같다. 1. 세라믹치형롤 분쇄속도 40rpm(0.352m/s)에서는 롤 회전비 2:1에서 1,190$\mu\textrm{m}$ 입자가 32.7%, 590$\mu\textrm{m}$ 입자가 19.7%였고, 롤 회전비를 5:1로 증가시 590$\mu\textrm{m}$ 입자가 30.9%, 420$\mu\textrm{m}$ 입자가 17.2%로 중간 미분쇄 영역의 분포가 증가하여 미분쇄 효율이 향상됨을 알 수 있었다. 2. 분쇄물의 롤 통과횟수에 따른 분쇄능은 세라믹치형롤 모두 분쇄속도 80rpm(0.704m/s)에서 분쇄물의 미분쇄능이 향상되었고, 분쇄생성물의 임계처리 횟수가 3~4차임을 분석할 수 있었다. 3. 보통 고춧가루를 생산하는데 분쇄속도 40rpm(0.352m/s), 80rpm(0.704m/s), 두 롤의 회전비 2:1, 3:1, 4:1하에서는 생산되지 않았으나, 롤 회전비 5:1에서는 분쇄속도 40rpm(0.352m/s)일 경우 7차 분쇄후에, 분쇄속도 80rpm(0.704m/s)일 경우 5차분쇄후에 생성되어 분쇄처리횟수가 2회정도 단축되어 전단력 증가로 인하여 분쇄능이 향상된 것으로 분석되었다. 4. 기존의 고춧가루 분쇄조건인 분쇄속도 40rpm(0.352m/s), 롤 회전비 2:1보다 본 연구에서 개발한 분쇄속도 80rpm(0.704m/s), 롤 회전비 5:1인 분쇄조건이, 분쇄처리 횟수 단축 등이 분석됨으로서 섬유질이 많이 포함된 고춧가루 등의 재료가공 분쇄기술이 향상된 것으로 분석되었다.. 마늘재배 일관기계화에 의한 노동투하시간과 비용 -종자준비부터 통마늘선별까지의 일관기계화로 투입된 주요작업의 노력은 75∼76%가 절감되고, 재배규모 3ha기준시 비용은 44-53%절감되었음. the annealing texture. Observations by TEM and EBSD revealed the formation of very fine grains of ∼1.0$\mu\textrm{m}$ after CCSS.he dislocations form local defect arrangements at the grooves permitting the substantial reduction in defect density over the remainder of the interfacial area.한 최대의 감자 재배지역을 형성하였다. 제주도는 산지지형과 따뜻한 기온으로 2기작이 가능하고, 감자가공 공장설립과 교통발달에 따른 육지 시장과의 접근이 용이해졌기 때문에 남한에서 2번째로 큰 감자재배지역이 되었다.(요약 및 결론에서 발췌)그람양성균에서 효과적이었으며, 농도별 항균력시험 결과 농도가 증가할수록 비례하여 저해율도 증가함을 알 수 있었다. 첨가농도를 달리하여 미생물의 생육도를 측정한 결과, fraction II磎꼭\ulcorner경우 그람양성균에 대해 500 ppm 이상에서 뚜렷한 증식억제효과를 나타내었다.서 뚜렷한 증식억제효과를 나타내었다.min/+}$계 수컷 이형접합체 형질전환 마우스에 AIN-76A 정제사료만을 투여한 대조군은 1.40$\pm$0.24(100%)에 비하여 I3C 저농도 투여 실험군(Group 1; 0.85$\pm$0.23; 61%, P<0.01), 그리고 I3C 고농도 투여 실험군(Group 2 ; 1.32$\pm$0.29 ; 94%)의 순으로 감소하였다. 선종의 크기별 종양의 발생개수의

• Journal of the Korean Geographical Society
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• v.41 no.4 s.115
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• pp.404-417
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• 2006

In order to clarify some characteristics of hydrological cycle in the subalpine zone of Mt. Halla, water balance has been analysed using hydrological data of a first-order drainage basin around Mansedongsan and meterological data of Odeung AWS. The experimental basin extends from 1,595 m to 1,645 m in altitude and has an catchment area of 1.34 ha. It is largely underlain by trachybasalt and covered with sasa bamboo and sedges. Hydrological observations were carried out every 20 minutes from April 15 to September 19, 2004. The basin shows the total precipitation of 3,074 m that is 1.6 to 3 times of those in coastal and intermontane regions. Surface runoff amounts to 850 mm that is equivalent to 27.6% of the precipitation. By contrast, evapotranspiration only accounts for 14.2% of the precipitation, and the remnant of 1,790 m penetrates underground through a basement. The basin is located in the subalpine zone and then it has a high rainfall intensity as well as a large rainfall due to frequent orographic precipitation. But surface runoff usually dose not exceed 30% of the rainfall while Percolation demonstrates about 2 times of the runoff. Compared with granite or gneiss basins in Korea Peninsula, the experimental basin is characterized by a higher portion of percolation in water balance. And it is probably related to the highly permeable basaltic lavas in Jeju Island which are also overlain by porous volcanic soils.

• Journal of the Korean Society of Radiology
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• v.13 no.6
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• pp.831-840
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• 2019

The X-ray detector by liquid crystal with front light was proposed and verified by a X-ray image. The proposed detector utilizes the visible light instead of the electric signal by transistor. Therefore, it shows low noise and can be fabricated at low cost. The liquid crystal detector uses the orientation change of the liquid crystal molecule by conductivity change of the photoconductive layer. We can get the X-ray image from the transmitted light through the liquid crystal. The X-ray dose was calibrated from the measured transmittance of the visible light after comparison to the reference transmittance curve of the liquid crystal. The amorphous Se was used for photo con ducting layer and parylene was used for the liquid crystal alignment instead of the conventional alignment layer which needs high-temperature process over 200℃. The proposed X-ray detector can decrease the X-ray dose by high sensitivity which was verified by simulation. After the fabrication of the X-ray detector, the X-ray image was obtained as a function of the bias voltage to the liquid crystal. 10 lines/mm resolution was obtained from the line pattern and we will apply it to the 17inch diagonal liquid crystal X-ray detector with 3π retardation.

• Pediatric Infection and Vaccine
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• v.9 no.1
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• pp.74-78
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• 2002

Purpose : Proper diagnosis of group A streptococcal pharyngitis that may cause chronic diseases in childhood is not easy because its signs and symptoms would be nonspecific. Because results of classical throat culture delays for one to two days, we'd like to determine whether early antibiotics would be introduced with according to the clinical score system. This study was undertaken to evaluate of clinical usefulness of scoring system based on the clinical and laboratory findings. Methods : From Jan. 1998 to Dec. 2000, 10 clinical items based on modified 9 items by Breese in 1977 were checked in patients with pharyngitis who visited on outpatients clinic of pediatrics, Kyunghee University Hospital. We compared the results of throat culture with the points of clinical score system. Results : Out of 45 cases, the positive culture for Group A Streptococcus was 20 and negative culture was 25. When we applied more than 30 points of score, which correspond to 70 percentile of study population, the sensitivity and specificity were 35.0% and 96.0%, respectively. Conclusion : Although sensitivity was relatively low this scoring system, but the high specificity may be useful diagnostic tool in the areas where the rate of isolation of Group A Streptococcus is low.