• 한국환경복원기술학회지
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• 제11권6호
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• pp.120-129
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• 2008

Removal rate of $NO_3-N$ and TN in a free water surface wetland system with litter layer on its bottom was compared with that without one. The system was established on floodplain in the down reach of the Gwangju Stream in 2001. Its dimensions were 31 meters in length and 12 meters in width. Water of the stream was funneled into it and its effluent was discharged back into the channel. Average litter layer of 9.6 cm was formed on its bottom in 2007. The layer and above-ground parts of reeds and cattails on the system were eliminated in Spring 2008. Volumes and water quality of inflow and outflow of the system were analyzed from May to November in 2007 and 2008, respectively. Inflow into the system both in 2007 and 2008 averaged approximately $40m^3/day$ and hydraulic residence time both in 2007 and 2008 was about 1.5 days. Average influent $NO_3-N$ concentration in 2007 and 2008 was 2.16 and 2.05 mg/L, respectively and influent TN concentration in 2007 and 2008 averaged 3.98 and 3.89 mg/L, respectively. With a 0.05 significance level, effluent temperatures, influent concentrations of $NO_3-N$ and TN, and stem numbers per square meter and height of the emergent plants showed no difference between the system with litter layer and without one. $NO_3-N$ removal in the system with litter layer and without it averaged 55.59 and 46.06%, respectively and TN retention averaged 57.24 and 48.97%, respectively. Both $NO_3-N$ and TN abatement rates in the system with litter layer were significantly high (p < 0.001) when compared with those without one. The wetland system having litter layer on its bottom was more efficient for $NO_3-N$ and TN retention than that without one.

• 수산해양기술연구
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• 제48권1호
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• pp.59-71
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• 2012

In order to elucidate the mechanism of fishing condition variation of anchovy in the set net fisheries of Anggang Bay, the monthly catch of anchovy was analyzed and examined based on the data acquired from 2006 to 2010 in 13 different fishing grounds. Anchovy consistently appeared from April to December and reached the production of 840 to 1,424 t (average : 1,228 t), with a big annual variation. However, anchovy production in this area accounts for approximately 75% of the production by set net in Anggang Bay whereas it holds 6.8% of the nationwide production (=18,034 t) by set net. The school of anchovy starts to appear in April at the west mouth of the bay and move north-eastward. Afterward, having three of clockwise turns in the middle of the bay, they scatter to swim into the deep place of the bay and finally go out to turn back to their coming way. These behaviors of anchovy are likely related to thermal fronts as well as distributions of food. The production of anchovy (y, kg) relied greatly on frequencies of effective northeasterly ($x_1$) or northwesterly ($x_2$) wind (${\leq}$3.5m/s) which blow between April and June. Their relationships are as follows: $y=1086.27+21.499x_1-15.16x_2$ (r=0.901). Consequently, we concluded that the northeasterly wind, which appears in the breeding season of spring, played a role to retard the movement of anchovy school to the eastern sea, while the northwesterly wind inhibits the invasion of anchovy school into the bay.

• 한국한의학연구원논문집
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• 제11권2호
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• pp.23-33
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• 2005

Four Properties and five Flavors of Drugs is interpreted by adaptation of human body to the environmental theory(天人相應). The Structural model of the body is compared with sky, earth, sun and moon (天, 地, 日, 月). The natural changes of the four seasons give rise to that of Four Properties and five Flavors of Drugs. On equal terms it is happened in our body. On this study we can draw an analogy between sky, earth, sun & moon (天, 地, 日, 月) and the body. The six bu(六腑) is related to the earth, the five ju(五主) to the sky, the five jang(五臟) to the sun, the meridians system (經絡) to the moon. When spring, the air is warm, the water element of the earth is ascending, and the earth gives birth to the sour flavor. Like this, the water element is absorbed by six bu and then is ascended to the meridian system. When summer, the air is hot and the water element of the earth is floated, the earth make the bitter flavor. In the same way, the six bu absorbed the hot air from the five ju and the water element is quickly absorbed by six bu and then the water element is ascended to the meridian system. When rainy season (長夏), the earth creates the sweet flavor The sweet flavor give warmer energy to the five jang and the six bu. When autumn, the earth change the sweet flavor into pungent. The earth gives warmer energy to the sky, because of cool weather According to same process, the pungent flavor give warmer energy to the five jang and the six bu, and the meridian system gets back the water element from the five ju. When winter, the air is cold and the water element of the earth is hidden. The sky and the earth are not interchangeable. At that time, the earth produce the salty flavor and the water element is keeping in the meridian system.

• 한국자동차공학회논문집
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• 제16권1호
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• pp.86-92
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• 2008

Recently, the use of tubes in the manufacturing of the automobile parts has increased and therefore many automotive manufactures have tried to use hydro-forming technology. The hydro-forming technology may cause many advantages to automotive applications in terms of better structural integrity of the parts, lower cost from fewer part count, material saving, weight reduction, lower spring-back, improved strength and durability and design flexibility. In this study, the whole process of front engine cradle (or front sub-frame) parts development by tube hydro-forming using steel material having tensile strength of 440MPa grade is presented. At the part design stage, it requires feasibility study and process design aided by CAE (Computer Aided Design) to confirm hydro-formability in details. Effects of parameters such as internal pressure, axial feeding and geometry shape on automotive sub-frame by hydro-forming process were carefully investigated. Overall possibility of hydro-formable sub-frame parts could be examined by cross sectional analyses. Moreover, it is essential to ensure the formability of tube material on every forming step such as pre-bending, preforming and hydro-forming. At the die design stage, all the components of prototyping tools are designed and interference with press is examined from the point of geometry and thinning.

• 한국대기환경학회지
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• 제24권2호
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• pp.162-175
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• 2008

Gyeongju, which was the central city of the ancient civilization at Silla Kingdom, has various kinds of stone cultural properties. It is significantly important to preserve historical sources of Korea. However, recent air quality data measured in Gyeongju did not show good air quality level. In order to investigate variation of the concentration of the air pollutants with meteorological condition, an air quality monitoring and an aerosol sampling were conducted during the intensive monitoring period in Gyeongju. Impacts of the meteorological factors on the air pollutants were also analyzed based on the air mass pathway categories using HYSPLIT model and the local wind patterns using MM5 model. The prevailing air mass pathways were classified into four categories as following; category I affected by easterly marine aerosols, category II affected by northwesterly continental aerosols, category III affected by southwesterly continental aerosols, and category IV affected by northerly continental aerosols. The concentrations of the air quality standards were relatively lower during the fall intensive monitoring period. At that time, the easterly marine air mass pattern was dominated. The seasonal average mass concentration of $PM_{10,Opt}$, which optically measured at the monitoring site, was the highest value of $77.6{\pm}28.3\;{\mu}g\;m^{-3}$ during the spring intensive monitoring period but the lowest value of $20.1{\pm}5.3\;{\mu}g\;m^{-3}$ during the fall intensive monitoring period. The concentrations of $SO_2$ and CO were relatively higher when the air mass came from the northwestern continent or the northern continent. The concentrations of ${SO_4}^{2-}$ and ${NO_3}^-$ increased under the northwesterly continental condition. It was estimated that the acidic aerosols were dominated in the atmosphere of Gyeongju when the air mass came from the continental regions.

• Journal of the Korean Wood Science and Technology
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• 제39권2호
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• pp.148-155
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• 2011

Thermal treatment techniques are used for modifying wood and wood-based materials to improve dimensional stability and hygroscopicity. This study investigated the effects of press pressure and temperature on density, vertical density profile, thickness swelling and surface hardness of eucalyptus wood boards. The experimental wood boards were prepared from Turkish River Gum ($Eucalyptus$ $camaldulensis$ Dehn.). The surface hardness value increased with increasing press pressure in the treated groups. The application of a higher pressure at the same temperature level increased the amount of swelling of wood. It means that it is not needed for application of higher pressure to enhance the dimensional stability of wood. It is expected that it is possible to produce increased hardness, dimensional stability and durability by application of hot pressing treatment. This research showed that different press pressure and temperature values should be used to improve the performance properties of eucalyptus wood so that the end-use of the wood materials could be expanded.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2008년 추계학술발표대회 논문집
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• pp.425-430
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• 2008

Residential architecture was a lot more changed due to adopting modern residential type since 1960s. But people in farm houses are still living in a space of their past life causing a discrepancy. For this reason, the paper will identify the changed use for farm houses focusing on their plane views, and reason for the changed use as well. The result of this paper is expected to play a role for practical data to reasonably change and re-model farm houses located in back of cities such as Hyunpoong area. Targeted area for this paper, in order to survey change in residential environment due to industrialization and modernization, has narrowed down to 42 farm houses which are located Yuga-Myun, Hyunpoong-Gun, Dalsung-Gun where tradition and modern characteristics are harmonized being built before 1960s Researching relied on both documentary records and survey on the site, and survey on documentary records was performed in a way that preceding research for changed use of residential area was to be compared with people's farm houses in Kyeongsang-Do area, and survey on the site was carried out by photographing and land surveying and interview and analysis for them, and finally we acquired the result by analyzing use of interior for houses and plane view and relations between culture and social environment. From the result of this paper, there was a trend that farm houses had been improved function of a specific space by enlarging space and enlarged construction for inner rooms. And among spaces, kitchen and bath room was mostly enlarged its left side, and inner room had mostly enlarged its rear side, and kitchen was frequently enlarged in its side space. These kinds of variation in space is believed to be result of change of life style and house facilities

• Asian-Australasian Journal of Animal Sciences
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• 제13권5호
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• pp.681-685
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• 2000

A computer software was developed in our laboratory to automatically control the pigs environment by the image analysis system (IAS), which monitors and analyzes the pig's behavior and feeds the results back to the computer hardware. Three feeding trials were conducted with growing pigs ($L{\times}Y$) to test the effectiveness of the IAS under various seasons. In all three trials, the open-sided conventional pens with half-slatted floor were used as controls; for the IAS treatment, fully-slatted floors were used in the windowless pens. Experiment 1 was conducted in the winter for 30 d with 24 growing pigs. There were two treatments (Conventional vs. IAS), and three pens (replicates) per treatment. During the growing period, the feed efficiency was significantly (p<0.05) improved by the IAS. In addition, the pigs reared under the IAS during the growing period displayed better growth rate during the finishing period than did the pigs reared under the conventional conditions. Experiment 2 was conducted in the summer for 30 d with 24 growing pigs. The experimental design was the same as Experiment 1. During the finishing period, all the pigs were kept in conventional open-sided pens until their market weights to evaluate their carcass characteristics. During the growing period, the growth rate and feed efficiency of the pigs in the IAS was better than those of the control pigs. In addition, various carcass characteristics were significantly improved by the IAS rearing during the growing period. Experiment 3 was conducted with 30 growing pigs for 30 d in the spring. The experimental design was the same as Experiment 1. No difference was found in growing performance between the control and IAS pigs. It could be concluded that the IAS is effective in providing optimum conditions for the growing pigs in summer and winter seasons. In addition, providing an optimum environment during the growing period results in improved growth rate, feed efficiency, and carcass qualities for the finishing pigs.

• 한국잠사곤충학회지
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• 제44권1호
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• pp.9-12
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• 2002

한반도에 자생하는 돌뽕나무(Morus tiliaefolia)의 임성과 재배학적 특성은 다음과 같다. 1. 종자형성률은 46∼80%이며 종자의 발아율은 19∼28%에 불과하다 2. 개화최성기(1994년)는 4월 28일∼5월 3일로서 산뽕나무보다는 늦고 개량뽕보다 빠르다 3. 춘기 동아의 탈포기는 4월 21일∼24일로서 산뽕나무와 개량뽕보다 늦다. 4. 잎은 대형으로 엽형지수 1.05의 폭광성을 나타내며 잎두께는 산뽕나무보다 두껍다. 5.성숙엽의 화학성분은 가용성 무질소물과 조회분이 많고 조단백질, 조지방, 조섬유가 적다. 6. 낮추베기때의 자세는 대부분 전개성이며 가지는 조장형이고 절간장이 길다 7. 추위견딜성과 뽕나무 동고병에 약하다.

• 한국잠사곤충학회지
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• 제44권1호
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• pp.22-27
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• 2002

용천뽕을 수원지방에서 비닐피복 밀식재배법으로 관리한 경우의 재배학적 특성은 다음과 같으며 동해발생시의 육잠 성과의 몇가지 예를 고찰하였다. 1. 춘기 탈포기는 개량뽕보다 3일 빠르나 5개엽기는 동일한 중생뽕이고 춘잠기 수확 당시 신소장은 길다. 2. 용천뽕의 수량은 개량뽕보다 춘잠기에 많고 추잠기에는 적은 춘형이다. 3. 용천뽕은 개량뽕보다 가지수가 약간 많고 지조장도 길어서 가지뽕치기에 적합하다. 4. 용천뽕은 뽕나무 눈마름병과 줄기마름병에 약간 강하고 오갈병에 다소 약하다. 5. 용천뽕은 내동성이 극히 강하여 동해상습지에 적합하며, 연도간의 육잠규모를 안정적으로 유지할수 있는 경영상의 이점이 있다. 춘천지방에서의 육잠성과에 있어서 동해의 빈도가 2년 1회의 경우에는 용천뽕이 개량뽕보다 11%증수 효과가 있었으며, 3년 1회 빈도의 경우는 두 품종이 비슷하였다.