• Korean Journal of Agricultural Science
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• v.9 no.2
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• pp.453-460
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• 1982

In order to investigate the effect of $AgNO_3$ pretreatment on reducing $SO_2$ injury in leaves of Forsythia koreana, changes of pH, chlorophyll content, peroxidase activity, sulfur content, and stomatal behaviour in leaves were examined. 1. $AgNO_3$ sprayed at 200 ppm or above increased black spot development in lower epidermis of leaves. But pretreatment with 100 ppm $AgNO_3$ significantly reduced de foliation and visible injury rate of leaves exposed to $SO_2$. 2. $AgNO_3$ pretreatment prevented lowering pH and decreasing chlorophyll content induced by $SO_2$ injury in leaves. But both $AgNO_3$ pretreatment and $SO_2$ exposure increased peroxidase activity in leaves. 3. $AgNO_3$ pretreatment did not affect reducing $SO_2$ absorption and stomatal opening in leaves exposed to $SO_2$.

• Journal of the Korean Institute of Gas
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• v.15 no.1
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• pp.15-21
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• 2011

Cost-benefit analysis (CBA) has been performed in order to decide whether the ILI (in-line inspection) suggested as risk mitigation measure (RMM) from quantitative risk assessment is reasonably practicable. As a result of CBA, we could find out the reasonable intervals of implementation of ILI. In order to assess the benefit, value of preventing a fatality (VPF), which measures value of human life, has been used. The adequate VPF figure of high pressure urban gas pipelines for CBA used in this paper is two billion won. As a result of 2 case studies, we found that the most reasonable intervals of ILI suggested as RMM were 13 years or 15 years.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2009.12a
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• pp.303-303
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• 2009

시설재배지의 연작장해 원인이 토양병해 35%, 염류집적 30%로 분석하고 있으며, 시설재배지의 40% 이상이 토양EC 4dS/m 이상으로 작물생육에 부적합한 염류집적 토양으로 추정하고있다. 연작 및 집약적인 시설 재배의 불가피성을 감안한 시설재배의 장기적인 토양관리를 위하여 녹비작물을 활용한 물질순환적 토양관리를 위하여 토양 EC가 상이한 3개(<2.0dS/m, 2.0~6.0dS/m, 6.0dS/m<)토양에 거울철 휴한기에 호밀, 밀, 청보리를 재배하고 토양에 환원한 후 수박을 재배하여 시험을 수행하였다. 녹비작물의 건물중생산량은 호밀이 601~722kg/10a, 밀이 433~607kg/10a, 청보리가 648~690kg/10a 이었으며, 토양EC가 높은 토양(6.0dS/m<)에서 가장 낮은 경향이었다. 녹비작물 재배 후 토양의 EC는 호밀재배에서 24~44%, 밀재배에서 19~38%, 청보리재배에서 23~39% 경감효과가 있으며, 3개 토양 평균 각각 녹비작물별 토양EC 경감 효과는 호밀, 밀 그리고 청보리 각각 37%, 31% 및 35%의 경향을 보였다. 녹비작물 재배 후 수박을 재배한 결과 수박의 생육 및 수량성은 토양 및 녹비작물 간에 뚜렷한 차이를 보이지 않았으나, 무재배에 비해서는 녹비작물재배 토양에서 약간 양호한 경향을 보이고 있어, 장기적으로 계속 재배할 경우 토양의 물리화학성 개선 및 작부체계 개선에 의한 연작장해 경감 효과를 기대할 수 있을 것으로 사료되었다.

• Journal of Chest Surgery
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• v.41 no.2
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• pp.247-252
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• 2008

Background: We compared the analgesic effects of an intravenous infusion of remifentanil with local lidocaine injection during endovenous laser treatments (EVLT) for varicose veins. Material and Method: In order to compare the efficacy of analgesia between the lidocaine group (n=15) and the remifentanil group (n=15), we measure the pain intensity of the patients, with using the visual analogue scale, during EVLT and at the first week, the second week, the third week and the fourth week after EVLT. Result: The remifentanil group showed significantly less pain intensity during EVLT (p<0.01), but there were no differences of pain intensity between the two groups from the first week to the fourth week after EVLT (p>0.3). Conclusion: The result showed that the intravenous infusion of remifentanil during EVLT can be a good option to reduce pain during EVLT for treating varicose veins.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.9
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• pp.789-794
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• 2014

The FPGA is used to the high speed digital satellite communication on the Digital Signal Process Unit of the next generation GEO communication satellite. The high capacity FPGA has the high power dissipation and it is difficult to satisfy the derating requirement of temperature. This matter is the major factor to degrade the equipment life and reliability. The thermal control at the equipment level has been worked through thermal conduction in the space environment. The FPGA of CCGA or BGA package type was mounted on printed circuit board, but the PCB has low efficient to the thermal control. For the FPGA heat dissipation, the heat sink was applied between part lid and housing of equipment and the performance of heat sink was confirmed via thermal vacuum test under the condition of space qualification level. The FPGA of high power dissipation has been difficult to apply for space application, but FPGA with heat sink could be used to space application with the derating temperature margin.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.1
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• pp.72-78
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• 2015

Recently, the usage of the satellite is increased more and more in the areas that are communication, weather, marine, optical, radar etc. The functions of the Satellite are evolving from passive transponder to active transponder by the developing of a technology. Advanced countries in satellites install the DCAMP for increase of bandwidth efficiency, improvement of QoS by interference rejection. DCAMP includes many digital components in order to implement functions. Thus, these kinds of active transponders consume much more power compared to passive transponder and then increase the heat. In this paper, we discuss the TVAC test result of DCAMP in EQM(Engineering Qualification Model) level. The paper shows the test results of digital gain control in order to verify DCAMP status under the TVAC test. In addition, the temperature and heat condition of main components from viewpoint of derating will be treated through the official environment test for qualification.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.4
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• pp.311-321
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• 2020

With the recent breakthrough in technology for micro-satellite, small satellite, and mega constellation missions, and the cost of accessing space from recycled space launch vehicles sharply lowered. Thus, space development is set to make a transition to a new space age that is different from before. Accordingly, the problem of worsening space environment conditions due to the increase in space debris, an inevitable adjunct to active space development, is also emerging as an international concern. In this paper, the contents and trends of international organizations for the protection of the space environment and space debris mitigation guidelines of each country were reviewed and forecast the future movement of the international community. In addition, it is suggested example of guidelines that fit the reality of Korea and how to apply them.

• Journal of Bio-Environment Control
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• v.9 no.2
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• pp.101-106
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• 2000

The practicality of utilizing ventilation pipe to enhance soybean sprout productivity by lowering commodity temperature and resultant sprout rot was tested. The ventilation pipes with holes for aeration were vertically installed inside of a sprout cultivation container prior to adding soaked soybean seeds. The time-series changes in sprout commodity temperature and resultant growth, yield, marketable sprout percentage, and rot of soybean sprouts were measured. The ventilation pipes effectively decreased sprout commodity decreased sprout commodity temperature by 4.7$^{\circ}C$. Ventilation pipes also enhanced sprout yield and marketable sprout percentage by 3.9% and 4.0%, respectively, while reducing sprout rot by 4.1%. In conclusion, ventilation pipe seems a practical and effective non-chemical method to enhance the productivity of soybean sprouts.

• Journal of Life Science
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• v.13 no.6
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• pp.775-781
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• 2003

In this study, we investigated to elevate the modulatory effect of flavonoid(fustin, sulfuretin, 10 mg/kg) which was isolated from Rhus verniciflua Stokes(RVS) in male Sprague-Dawley rats for 2 weeks on the toxicity of paraquat. In the flavonoids pretreated groups, glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, blood urea nitrogen, creatinine, malondialdehyde and alkaline phosphatase activity in serum and malondialdehyde, alkaline phosphatase activity and collagen in lung tissue which was induced paraquat toxicity were slightly decrease compared to the normal group. In the lung tissue of flavonoids pretreated groups, malodialdehyde value, G-6-phosphatase activity and collagen synthesis were recovered to tile normal values and alkaline phosphatase activity was increased. From these results, we concluded that flavonoids which were isolated from RVS is an effective agent to inhibit the pulmonary and internal toxicities and hence we concluded that acitive components of fustin and sulfuretin which were isolated from RVS might be removed free radicals induced by paraquat.

• Journal of the Korean Institute of Gas
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• v.14 no.4
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• pp.18-23
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• 2010

After conducting QRA(quantitative risk assessment) for the high pressure urban gas pipelines planned to be installed, RMMs(risk mitigation measures) when the societal risk is outside the acceptable region have been derived in this paper. Also risk reduction rates are calculated for each RMM. As a result of QRA, we find out that damaged distance caused by radiational heat is largely dependent upon the wind velocity and the atmospheric stability. The measure that has the highest risk reduction effect is No. 10 which includes pipeline corrosion monitoring, MOV(motor operated valve) installation and the method to protect pipeline damage caused by third-party mechanical interference, and which shows 75 % of risk reduction effect.