• Food Science and Preservation
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• v.19 no.6
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• pp.799-806
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• 2012

This experiment was conducted to establish the optimum conditions for high $CO_2$ gas treatment in combination with a proper gas-permeable packaging film to maintain the quality of fig fruit (Ficus carica L). Among the fig fruits with different high $CO_2$ treatments, the quality change was most effectively controlled during storage in the 70%-$CO_2$-treated fig fruit. Harvested fig fruit was packaged using microperforated oriented polypropylene (MP) film to maintain the optimum gas concentrations in the headspace of packaging for the modified-atmosphere system. MP film had an oxygen transmission rate of about $10,295cm^3/m^2$/day/atm at $25^{\circ}C$. The weight loss, firmness, soluble-solid content (SSC), acidity (pH), skin color (Hunter L, a, b), and decay ratio of the fig fruits were monitored during storage at 5 and $25^{\circ}C$. The results of this study showed that the OPP film, OPP film + 70% $CO_2$, and MP film+70% $CO_2$ were highly effective in reducing the loss rate, firmness and decay occurrence rate of fig fruits that were packaged with them during storage. In the case of using treatments with packages of OPP film and OPP film+70% $CO_2$, however, adverse effects like package bursting or physiological injury of the fig may occur due to the gas pressure or long exposure to $CO_2$. Therefore, the results indicated that MP film containing 70% $CO_2$ can be used as an effective treatment to extend the freshness of fig fruits for storage at a proper low temperature.

• The Journal of Engineering Geology
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• v.15 no.2 s.42
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• pp.213-227
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• 2005

This study aims to assess the problems with investigation method and to suggest the complementary solutions by comparing the predicted data from surface investigation with the outcome data from underground cavern. In the study area, one(NE-1) of 6 fracture zones predicted during the surface investigation was only confirmed in underground caverns. Therefore, it is necessary to improve the confidence level for prediction. In this study, the fracture classification criteria was quantitatively suggested on the basis of the BHTV images of NE-1 fracture zone. The major orientation of background fractures in rock mass was changed at the depth of the storage cavern, the length and intensity were decreased. These characteristics result in the deviation of predieted predicted fracture properties and generate the investigation bias depending on the bore hole directions and investigated scales. The evaluation of hydraulic connectivity in the surface investigation stage needs to be analyze by the groundwater pressures and hydrochemical properties from the monitoring bore hole(s) equipped with a double completion or multi-packer system during the test bore hole is pumping or injecting. The hydraulic conductivities in geometric mean measured in the underground caverns are 2-3 times lower than those from the surface and furthermore the horizontal hydraulic conductivity in geometric mean is six times lower than the vertical one. To improve confidence level of the hydraulic conductivity, the orientation of test hole should be considered during the analysis of the hydraulic conductivity and the methodology of hydro-testing and interpretation should be based on the characteristics of rock mass and investigation purposes.

• Journal of Bio-Environment Control
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• v.4 no.1
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• pp.59-67
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• 1995

This study was conducted to develope the automatic insulation system which control inside temperature of the greenhouse. For this purpose, the double- wall greenhouse and system which could automatically supply and discharge styrene pellets were constructed and abrasion of the pellets, blower ability, insulating property, transmittance and shading effect were analyzed by the experiments. The results obtained from this study can be summarized as follows : 1. It took an hour and fifteen minutes to supply and discharge about 2㎥ pellets in the experimental greenhouse. However, it is possible to reduce the operation time by proper selection of the blower and exhaust port, and by proper control of the supply and return pipe. 2. It was founded that the indirect delivery way was more profitable than the direct one in the supply and return of pellets. 3. When the transmittance was measured between 10 a.m. and 3 p.m., the average light transmissivity rate was 67%. 4. In winter nighttime, the inside temperature of the double- wall greenhouse with out the pellets was higher than the outside temperature by 3.4$^{\circ}C$ on an average. However, the inside temperature of the double - wall greenhouse with insulated area 73% was higher than the outside by one 6.6$^{\circ}C$ on an average, and the inside temperature of the greenhouse with insulated area 100% was higher than outside one by 13.5$^{\circ}C$ on an average. Therefore, it was proved that the insulating ability of the double - wall greenhouse in nighttime was excellent. 5. When the outside temperature was 36.9$^{\circ}C$ on an average, the inside temperature of the double- wail greenhouse with insulated area 100% was 3$0^{\circ}C$ on an average. As the inside temperature was lower than the outside one by 7$^{\circ}C$ on an average, we could know that the shading effects of the double- wall greenhouse were excellent in summer daytime.

• Korean Journal of Environmental Biology
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• v.37 no.2
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• pp.155-163
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• 2019

The Paralichthys olivaceus (mean weight 34.3±3.5 g) was used in the conduction of density experiment in this study to establish the optimal density determination for a period of 13 weeks. The density consisted of four groups. These were group 1 (500 fish, 40 fish m^-2), group 2 (750 fish, 60 fish m^-2), group 3 (1,000 fish, 80 fish m^-2) and group 4 (1,250 fish, 100 fish m^-2), each in 12.56 ㎡ circular water tanks. In the high density groups, such as groups 1 and 2, the nitrite was increased to over 21 mg L^-1 (group 3) and 25 mg L^-1 (group 4). The experiment of the groups was terminated by skin ulcers and mortality after 49 days for group 3 and 43 days for group 4. The water quality environment, such as the water temperature, dissolved oxygen, salinity and pH, remained constant. The ammonia and nitrite in groups 1 and 2 remained stable after ammonia and nitrite peak. However, the experiments in groups 3 and 4 were terminated due to the mortality induced by high nitrite. Hematological parameters, such as hemoglobin and hematocrit, were significantly decreased in the high density groups. The plasma components were significantly changed in the high density groups, such as groups 3 and 4. The mean weight of groups 1 and 2 after 13 weeks were 91.3 g and 83.7 g, respectively. The survival rates were 99.4% and 98.2%, respectively. The final FCR was 0.6 in both groups. The results of this study show that the density of 80 fish m^-2 or more induce mortality due to high nitrite with hematological changes. Additionally, they indicate that the 60 fish m^-2 indicate proper density in bio-floc environment in olive flounder weighing less than 100 g.

• Journal of Bio-Environment Control
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• v.8 no.2
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• pp.136-146
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• 1999

A series of experiments were carried out in winter to investigate the indoor thermal environment in greenhouses with different kinds of heating systems, and characterize the energy consumption, heat transport and thermal energy efficiency of each system. By the Quantitative calculation of heat losses which transmit through the covers of greenhouse, the fundamental data of energy-saving of the particular heating system were obtained. And from the analysis of air temperature differences between indoor and outside, it was possible to select more effective energy-saving and comfortable heating system in greenhouses. The electric heater was more stable in thermal environment and cheaper in cost, since it could be used during the surplus time of electric power from 10：00 p.M. to 8：00 A.M. But the low air temperature in greenhouses besides these times resulted in a chilling problem of the crops. The heating system by hot air had the advantage to show nearly uniform temperature difference by the height above the ground. But the system had the disadvantage to require more energy consumption than the electric heating system.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.17 no.2
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• pp.61-69
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• 2005

The coastal erosion and the look of a heap which are mainly occurred in the district along the coast are found for various forms such as the estuary closing, the estuary sand bar the development of the coast sand bar, and the modification of coastline. Recently, due to the coastal development, these transformations have been intensified. The change of coast, which has been made slow progress is required long-term study on a searching examination of the root cause and a suggestion of a counter measure. In this research, ortho aerial photos were produced to analyze volumes of topographical alternations that have been progressed fer the long run, by 10s cycle from 1940s through 1990s, to compute accurate volumes of coastline variation, through a datum point and G.C.P (Ground Control Point). Also in this study, without respect to water level, the coastline variation was analyzed by using comparatively analyzed a Idlest land map, a cadastral map. And to analyze topographical variation volumes, the tidal station's materials was used under consideration f3r tide. Finally, topographical variation volumes are comparatively analyzed through surveying and sounding and a point of fine of aviation photographing was calculated and revised. After this research, by using ortho aerial photos, We can understand efficiency of these in computing volumes of variations of coastline by analyzing quantitatively erosion and look of a heap. Besides, in the future, these will be used for information gathering of the coastline integration control system.

• 한국공간정보시스템학회:학술대회논문집
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• 2001.11a
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• pp.275-286
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• 2001

습지 분류의 목표는 '목록작성(inventory)과 평가와 관리를 위해 자연적인 생태계에 범위를 설정하는 것'이다. 또한 등질적인 속성을 갖는 생태단위를 기술하고, 자원관리 의사결정에 도움을 줄 수 있는 체계로 단위를 만들어내고, 목록작성과 지도화에 필요한 단위를 제공하면, 습지에 관한 개념과 용어의 통일성을 제공하는 것 등이다. 해안지형 가운데 해안 습지의 분류에는 우선, 1) 형태, 2) 생성요인, 3) 자갈, 모래, 펄 같은 기질 물질과 4)현재의 환경이라는 요소가 모두 고려되어야만 하는데 아직 국내에는 이에 대한 연구가 절대적으로 부족하여 이에 대한 규정이 부족한 현실이다. 따라서 현 단계에서 ISO/IEC 규정대로 각 코드는 엄밀히 상호배타적인 개념일 것, 정수로 표시할 것과 순차적으로 증가하는 숫자로 표시할 것 등의 전제조건을 만족시키는 전제 하에서 해안습지를 분류하는 것은 매우 힘든 작업이라 생각한다. 하지만 국토공간의 효율적 관리와 보존을 위해서는 위치와 장소에 따라 차이를 보이는 지질, 지형, 토양, 식생, 수리 현상 등 제반 지표 환경요소에 대한 체계화된 정보의 축척이 있어야 가능하다. 우리나라의 경우 지질 정보는 지질자원연구원에서 발행하는 지질도와, 농촌진흥청에서 발행하는 토양도, 임업연구원에서 발행하는 임상도 등의 주제도가 있으나, 지표환경을 나타내주는 지형에 대한 정보체계는 아직 이루러진 바가 없고, 대학의 석사학위논문이나, 실험적인 수준의 연구에 머물고 있는 실정이다. 이번 연구에서는 지형분류도 작성과 관련한 외국의 사례를 집중적으로 분석하고, 지형정보의 체계적 관리를 위해 가장 필요한 해안습지 지형분류도를 작성하기 위해 가장 기초적인 단계인 해안습지 지형분류체계에 대한 국내외의 연구성과를 비교하여 시안을 작성 표준화를 위한 첫 단계 시도를 소개하였다.분석 결과는 문장, 그림 및 도표, 장 끝의 질문, 학생의 학습 활동 수 등이 $0.4{\sim}1.5$ 사이의 값으로 학생 참여를 적절히 유도하는 발견 지향적 인 것으로 조사되었다. 그러나 장의 요약은 본문 내용을 반복하는 내용으로 구성되었다. 이와 같이 공통과학 과목은 새로운 현대 사회에 부응하는 교과 목표와 체계를 지향하고 있지만 아직도 통합과학으로서의 내용과 체계를 완전히 갖추고 있지 못할 뿐만 아니라 현재 사용되고 있는 7종의 교과서가 교육 목표를 충분히 반영하지 못하고 있다. 따라서 교사의 역할이 더욱더 중요하게 되었다.괴리가 작아진다. 이 결과에 따르면 위탁증거금의 징수는 그 제도의 취지에 부합되고 있다. 다만 제도운용상의 이유이거나 혹은 우리나라 주식시장의 투자자들이 비합리적인 투자형태를 보임에 따라 그 정책적 효과는 때로 역기능적인 결과로 초래하였다. 그럼에도 불구하고 이 연구결과를 통하여 최소한 주식시장(株式市場)에서 위탁증거금제도는 그 제도적 의의가 여전히 있다는 사실이 확인되었다. 또한 우리나라 주식시장에서 통상 과열투기 행위가 빈번히 일어나 주식시장을 교란시킴으로써 건전한 투자풍토조성에 저해된다는 저간의 우려가 매우 커왔으나 표본 기간동안에 대하여 실증분석을 한 결과 주식시장 전체적으로 볼 때 주가변동율(株價變動率), 특히 초과주가변동율(超過株價變動率)에 미치는 영향이 그다지 심각한 정도는 아니었으며 오히려 우리나라의 주식시장은 미국시장에 비해 주가가 비교적 안정적인 수준을 유지해 왔다고 볼 수 있다.36.4%)와 외식을 선호(29.1%)${\lrcorner}$ 하기 때문에 패스트푸드를 이용하게 된 것으로 응답 하였으며, 남 여 대학생간에는 유의한 차이(p<0.05)가 인정되었다. 응답자의 체형은 ${\ulcorner}$

• Journal of Environmental Science International
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• v.19 no.11
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• pp.1397-1405
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• 2010

Mass mortalities of cultivated organisms have occurred frequently in Korean coastal waters causing enormous losses to cultivating industry. The preventive measures require continuous observation of farm environment and real-time provision of data. However, line hanging aquaculture farm are generally located far from monitoring buoys and has limitations on installation of heavy equipments. Substituting battery pack for solar panels and miniaturizing size of buoy, newly developed system can be attached to long line hanging aquaculture farm. This system could deliver measured data to users in real-time and contribute to damage mitigation and prevention from mass mortalities as well as finding their causes. The system was installed off Gijang and Yeongdeck in Korea, measuring and transmitting seawater temperature at the sea surface every 30 minutes. Short term variation of seawater temperature, less than one day, in Gijang from June to July 2009 corresponded tidal period of about 12 hours and long term variation seemed to be caused by cold water southeast coast of Korea, particularly northeast of Gijang. Seawater temperature differences between Gijang station and the other station that is about 500 m away from Gijang station were $1^{\circ}C$ on average. This fact indicates that it is need to be pay attention to use substitute data even if it is close to the station. Daily range of seawater temperature, one of crucial information to aquaculture, can be obtained from this system because temperature were measured every 30 minutes. Averages of daily range of temperature off Gijang and Yeongdeok during each observation periods were about $2.9^{\circ}C$ and $4.7^{\circ}C$ respectively. Dominant period of seawater temperature variation off Yeongdeok was one day with the lowest peak at 5 a.m. and the highest one at 5 p.m. generally, resulting from solar radiation.

• Archives of design research
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• v.13 no.2
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• pp.73-80
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• 2000

In this study design information was separately defined form general product information and thus factors reflected in product design ion the basis of values and roles were extracted. The following is a classification of 5 different types of design factors divided according to their disposition. ·Innovation factor - element which previously did not exist or element related with explicit reformation ·Open factor - active element which not only improves current performance but also induces new functions through understanding of usage situations and new possibilities. ·Anterior factor - element which prolongs and develops the early development requirements of products through C.I. and P.I. related elements and characteristics of previous models and design strategy. Self-evidence factor - element related with function visualization through product structure which may make possible the consolidation of shape and function. Rigid factor - element, based on the human factors engineering, related with the safety and efficiency of users. This classification was obtained by defining major characteristics of products considering the target consumer and market characteristics. In this classification factor structuring design process which efficiently deducted a differentiated final product by synthesizing factors of higher importance as dominant factors was proposed. With this kind of factor structuring process, product differentiation may be achieved by bestowing individual characteristics to each product by combining design dominant factors associated with the product for a specific purpose from the stages of product concept development. Moreover, this may be used as an approach to actively correspond to the various and specific demands of the comsumer.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.2 s.302
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• pp.27-36
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• 2005

This thesis proposed an effective encryption method for the DCT-based image/video contents and made it possible to operate in a high speed by implementing it as an optimized hardware. By considering the increase in the amount of the calculation in the image/video compression, reconstruction and encryption, an partial encryption was performed, in which only the important information (DC and DPCM coefficients) were selected as the data to be encrypted. As the result, the encryption cost decreased when all the original image was encrypted. As the encryption algorithm one of the multi-mode AES, DES, or SEED can be used. The proposed encryption method was implemented in software to be experimented with TM-5 for about 1,000 test images. From the result, it was verified that to induce the original image from the encrypted one is not possible. At that situation, the decrease in compression ratio was only $1.6\%$. The hardware encryption system implemented in Verilog-HDL was synthesized to find the gate-level circuit in the SynopsysTM design compiler with the Hynix $0.25{\mu}m$ CMOS Phantom-cell library. Timing simulation was performed by Verilog-XL from CadenceTM, which resulted in the stable operation in the frequency above 100MHz. Accordingly, the proposed encryption method and the implemented hardware are expected to be effectively used as a good solution for the end-to-end security which is considered as one of the important problems.