• Journal of Ecology and Environment
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• v.29 no.3
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• pp.295-303
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• 2006

Clear-cut followed by tree planting has been a conventional management practice in burned forests in Korea. Because this can considerably increase soil loss, hillslope treatments may be needed in order to improve soil stability at poorly regenerating areas. This paper reviews the effects of hillslope treatments, such as seeding, mulching and log erosion barriers, which have been applied to restore vegetation and conserve soil in burned forests in North America and Europe. Seeding has been the most common method for postfire restoration. However, the effects of seeding on vegetation cover and soil erosion are not clear and seeding with non-native species has been reported to inhibit regeneration of native vegetation. Mulching has been found to be effective at reducing soil erosion. However, this also can introduce non-native plant species and inhibit native plant regeration. Although studies on the effect of log erosion barriers are very few, it appears that log erosion barriers are effective in the period of little rainfall. Hillslope treatments for postfire restoration is not necessary for naturally regenerating areas and therefore, they should be restricted to the areas where regeneration potential is low and runoff and soil loss is considerable. Long-term monitoring is needed to assess the effectiveness of hillslope treatments on soil erosion, the introduction of non-native plant species and the inhibition of natural plant regeneration.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.4
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• pp.85-101
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• 2013

The primary goal of this research is to link two currently disconnected literature; the history of urban redevelopment and the one of urban parks and open spaces in the United States (US). Through this exercise, this study attempts to reveal examples of urban parks and open spaces that have yielded economic effects, and emphasize their possibility as a measure of urban redevelopment. Five phases are presented, starting with two Pre-World War II urbanization periods, and three subsequent periods of Post-World War II urban redevelopment (1940s~1960s, late 1960s~1970s, 1980s~present). While urban parks in the 19th century urbanization period held a preeminent place in urban design, policy and economy, ensuing depression and World War II diminished their role as a channel to ease unemployment. In the first phase of urban redevelopment, the economic motive to build open space was to boost the appeal of specific locales in order to draw people and businesses back to a neglected city. In the second phase, public effort to create and maintain urban parks and open spaces declined due to the budget austerity, instead, community open spaces flourished through the voluntary actions and helped neighborhoods to regain desirability. In the third phase, the aspirations and functions of such projects resemble their forerunners of the first phase, but their targets extended to global businesses and elites.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.5
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• pp.91-96
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• 2009

The number of vehicles applied diesel engine are rapidly rising for fuel economy. Accompanying this trend, application of an after-treatment system is strictly required as a result of reinforced emission regulation. The Diesel Particulate Filter (DPF) system is considered as the most efficient method to reduce particulate matter by car makers but also in retrofit market. In this paper we discussed the optimization of active regeneration timing by comparing the fuel consumption from back pressure caused by PM loading and from active regeneration. The effects of back pressure of DPFs during PM loading, active regeneration condition and engine emission(PM) on additional fuel consumption are experimentally investigated and the proper regeneration timings according to DPF systems and fuel loss for 160,000km are determined.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.4
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• pp.10-16
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• 1980

Five of each lowland and upland rice varieties were planted in a seedling hox with three replications of randomized complete block design and it was desiccated up to complete water stress in certain leaf stage. The desiccated rice plants were supplied with water again to check survival ability of rice plant from wilting. All of the lowland varieties which showed lower yield in upland condition were superior to upland varieties in recovery ability from desiccation. Some of the morphological characteristics in relation to the recovery ability also were discussed.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.153-153
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• 2011

신 재생에너지 정책이 발전차액지원제도(Feed In Tariff; FIT)에서 신 재생에너지 의무할당제(Renewable Portfolio Standard; RPS)로 변화하면서 원별 경쟁이 가속화되고 있다. 태양광 산업 역시 이러한 환경 변화에 대처해야 하며, 그를 위한 정책 구성이 필요하다. 이에 태양광 산업 정책은 크게 두 부분으로 구분하여 진행해야 한다. 첫째, 폴리실리콘(Poly silicon)을 활용하는 다결정실리콘 태양광에너지에 초점을 맞춘 정책이며, 둘째, 미래에 상용화될 차세대 태양광 에너지에 대한 대비를 위한 연구 개발(R&D) 정책이다. 먼저 다결정실리콘 태양광에너지에 초점에서의 산업 정책은 산업육성정책과 수출정책, 인프라 구성 등으로 나눌 수 있다. 현재 과도한 국가부채로 인한 세계경제 악화로 태양광에너지 업체들의 경제성이 악화하고 있다. 더욱 빨리 그리드 패리티(Grid Parity)를 달성하기 위해 수직통합 등의 필요성이 대두하고 있다. 이에 본 연구는 그리드 패리티 달성시기를 위해 태양광 산업 내 세대 변화를 하는 경우와 하지 않는 경우를 비교하기 위해 고려할 요소를 분석하였다. 현재 신 재생에너지 가운데 태양광에너지는 타에너지원 대비 가격경쟁력을 갖추지 못한 상황이다. 그러나 수출을 고려했을 때의 향후 한국의 차세대 성장동력으로의 발전가능성이 존재한다. 따라서 가격경쟁력이 가장 중요한 영향을 미칠 신 재생에너지 의무할당제 정책 하에서 태양광에너지가 전혀 채택되지 않는 상황을 막기 위한 정책이 필요하다. 그를 위해 필요한 정책적 요소들을 알아보았다. 마지막으로 인프라 구성을 위해 태양광 산업의 가치사슬(Value Chain) 상에서의 기업 분포와 경쟁력에 대한 조사를 시행하였다. 이는 태양광 산업 내의 경쟁력을 갖춘 부문과 그렇지 못한 부문을 구별하기 위함이다. 미래에 상용화될 차세대 태양광 에너지를 준비하는 과정에서는 연구개발 관련 정책이 가장 중요하게 다뤄야 할 부분이며, 그를 위해 정부 차원에서 지원하고자 하는 기술로드맵 등에 대해서 정리하였다.

• Journal of the Korean Society of Radiology
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• v.15 no.4
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• pp.539-545
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• 2021

Radiation therapy is accompanied by adverse radiation effective. In particular, it is accompanied by disorders of the vascular system. Therefore, oxygen and nutrient deficiency occurs in the regeneration area. Eventually, osteoradionecrosis is formed in this cellular environment. According to a precedent study, bone morphogenetic protein-2 is used to overcome osteoradionecrosis. The purpose of this study was to investigate the regeneration ability of osteoradionecrosis by treating bone-forming protein-2 on a fibrinogen scaffold which is a biomaterial that is frequently used for bone regeneration after irradiation of the rat head. In addition, the purpose of this study was to verify the bone regeneration effect from the eight weeks. According to the experimental results, in the calvarial defected model of the irradiated mouse, making bone-formation was obtained after 8 weeks rather than bone-formation period in the early 4 weeks. moreover, it was found that the regenerated bone formation of the fibrinogen scaffold is formed from the inside of the bone of the defect area.

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.1
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• pp.30-40
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• 2020

Monitoring the urban environmental changes caused by the urban regeneration project is necessary for evaluating the effect of the various types of urban regeneration projects that have been carried out in Seoul, South Korea. However, there is few available data and professional expert for evaluating the effect of these urban regeneration projects. This research evaluated the effect of the construction of rainwater village in Jangwi-dong area, constructed through the Seoul urban regeneration project, by utilizing the land surface temperatures derived from the multi-temporal Landsat-8 satellite images through the following steps. In the first step, the land surface temperature images were generated using the multispectral bands of the Landsat-8 satellite images. In the final step, the effect of constructing the rainwater villages was assessed by calculating the seasonal LST statistics for Jangwi-dong area, its neighbor area and entire Seoul area. The experimental results led the following conclusion: the construction of rainwater villages did not have the significant effect on the land surface temperature changes in Jangwi-dong area.

• The Korean Journal of Zoology
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• v.39 no.1
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• pp.65-74
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• 1996

Treatment of regenerating amphibian limbs with retinoic acid (RA) is known to induce paftern duplication, which is closely related to the extent of dedifferentiation. In the present study, the activities of trypsin- and chymotrypsin-like proteases are examined to delineate a possible role in the process of dedifferentiation in the regenerating limbs of urodeles, the Korean salamander (Hynobius leechii) and the Mexican axolod (Ambystoma mexicanum). Specifically, we were interested to know if there is any correlation between trypsin- and chymotrypsin-like protease activities and the state of dedifferentiation which is augmented by RA treatment. We were also interested in expoloring if there is any species-specific difference in the profile of enzyme activities during limb regeneration. The results showed that the activities of these two enzymes reached a peak level at dedifferentiation stage, and RA treatment caused elevation of their activities, especially in the case of trypsin-like protease. The increase of trypsin-like protease activity after RA treatment was pronounced in the Korean salamander, which might reflect a species-specific responsiveness to RA. The present results imply that trypsin and chymotrypsin or similar proteases may play an active role in the process of dedifferentiation in regenerating limbs, and that trypsin or trypsin-like eryrymes might be involved in the RA-evoked enhancement of dedifferentiation which precedes overt pattern duplication.

• Radiation Oncology Journal
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• v.15 no.2
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• pp.79-95
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• 1997

Purpose : Phospholipase C(PLC) isozymes play significant roles in signal transduction mechanism. $PLC-\gamma$ 1 is one of the key regulatory enzymes in signal transduction for cellular proliferation and differentiation. Ras oncoprotein, EGFR, and PKC are also known to be involved in cell growth. The exact mechanisms of these signal transduction following irradiation, however, were not clearly documented Thus, this study was Planned to determine the biological significance of PLC, ras oncoprotein, EGFR, and PKC in damage and regeneration of rat intestinal mucosa following irradiation. Material and Method : Sixty Sprague-Dawley rats were irradiated to entire body with a single dose of 8Gy. The rats were divided into S groups according to the sacrifice days after irradiation. The expression of PLC, ras oncoprotein, EGFR and PKC in each group were examined by the immunoblotting and immunohistochemistry. The histopathologic findings were observed using H&I stain, and the mitoses for the evidence of regeneration were counted using the light microscopy & PCNA kit. The Phosphoinositide(PI) hydrolyzing activity assay was also done for the indirect evaluation of $PLC-\gamma$ 1 activity. Results: In the immunohistochemistry , the expression of $PLC-{\beta}$ was negative for all grøups. The expression of $PLC-{\gamma}1$ was highest in the group III followed by group II in the proliferative zone of mucosa. The expression of $PKC-{\delta}1$ was strongly positive in group 1 followed by group II in the damaged surface epithelium. The above findings were also confirttled in the immunoblotting study. In the immunoblotting study, the expressions of $PLC-{\beta}$, $PLC-{\gamma}1$, and $PKC-{\delta}1$ were the same as the results of immunohis-tochemistry. The expression of ras oncoprctein was weakly positive in groups II, III and IV. The of EGFR was the highest in the group II, III, follwed by group IV and the expression of PKC was weakly positive in the group II and III. Conclusion: $PLC-{\gamma}1$ mediated signal transduction including ras oncoprotein, EGFR, and PKC play a significant role in mucosal regeneration after irradiation. $PLC-{\delta}1$ mediated signal transduction might have an important role in mucosal damage after irradiation. Further studies will be necessary to confirm the signal transduction mediating the $PKC-{\delta}1$.

• Korean Journal of Weed Science
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• v.9 no.1
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• pp.34-38
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• 1989

This study was conducted to investigate the tuberization time and the control method for Eleocharis kuroguwai Ohwi. The control methods were compared the shoot cutting and bentazon treatment for E. kuroguwai with untreatment. The initial tuberization time of E. kuroguwai, when E. kuroguwai was planted and without rice planted, was about August 18th and 10th, respectively. When the shoot of E. kuroguwai was cut, the regrowth vigour scarcely revived for the cutting on September 12. The least tuberization of E. kuroguwai, when E. kuroguwai was just planted and planted with rice plant, were on August 28 and August 3 to the top cutting of E. kuroguwai, respectively. Bentazon treatments from July 19 to August 3 hardly induced tuberization of E. kuroguwai, while as the delay of bentazon treatment time the tuberization of E. kurguwai was little by little increased.