• Ecology and Resilient Infrastructure
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• 제2권3호
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• pp.247-254
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• 2015

Changes in land-use type can affect soil and water properties in stream ecosystems. This study examined the effects of different land-use types on biogeochemical properties and microbial activities of a stream. We collected water and sediment samples in a stream at three different sites surrounded by varying land-use types; a forest, a radish field and a rice paddy. Nitrogen contents, such as nitrate, nitrite and total nitrogen in the stream water body, showed significant differences among the sampling sites. The highest nitrogen values were recorded at the site surrounded by cropland, as fertilizer runoff impacted the stream. Soil organic matter content in the sediment showed significant differences among sites, with the highest content exhibited at the forest mouth site. These differences might be due to the organic matter in surrounding terrestrial ecosystems. Microbial activities determined by extracellular enzyme activities showed similar values throughout all sites in the water body; however, the activities in the sediments exhibited the highest values near the forest site and mirrored the soil organic matter content values. From these results, we conclude that different land-use types are important factors affecting water and sediment properties in stream ecosystems.

• 한국재난정보학회 논문집
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• 제10권3호
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• pp.466-480
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• 2014

대한민국은 사회적 고령화 문제와 더불어 재난현장 대응활동의 주역인 소방공무원 조직의 연령 구성비의 고연령화 문제 또한 심각한 상황에 이를 것으로 전망된다. 대표적인 재난대응조직인 서울소방의 경우 향후 10년~15년 사이에 50대 이상의 비율이 31%에서 40%에 이를 것으로 예상되는데, 이는 재난 현장에서 강인한 체력과 건강한 신체를 필수 요소로 하는 소방공무원에 있어서는 일반직 공무원과는 달리 심각한 문제가 되지 않을 수 없다. 본 연구는 서울 소방공무원의 연령현황과 추이를 분석하고 국내 최초로 현장활동 소방공무원의 현장활동 한계의 기준 연령을 정의하고 3가지 분석기준을 통해 개괄적이나마 현장활동 한계기준을 도출하고, 이 기준을 통해 추이분석을 하였다.

• 한국환경과학회지
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• 제11권9호
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• pp.843-849
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• 2002

According to tourism resources in Kyonggi province, tourist behavior was dramatically different in that tourists utilizing natural resources were mainly interested in static tourism activities and sight seeing activities while tourist using socio-cultural resources preferred with dynamic tourism activities and relaxation tourism. Therefore, the objectives of reconstruction should be adjusted depending on types of tourism resources (i.e. natural and socio-cultural resources) or natural intensity as well as the development goal of recreational tourism. In contrast, historic and cultural resources surrounded with natural resources showed higher revisit rate, and was conceived as better touring site than individual resource because of historical people, traditional custom, natural sight seeing, etc. Therefore, it is believed that proper utilization of natural resources will increase revisit rate and create new conception as a famous touring site.

• Journal of Ecology and Environment
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• 제46권3호
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• pp.204-217
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• 2022

Background: Increasing land demands for food production have led to biodiversity loss and land degradation in the Madhupur Sal forest. Reforestation activities such as agroforestry and woodlot plantation support the conservation of diversity, restoration of forest and prevention of soil erosion in degraded natural Sal forest. Knowing about these reforestation activities, this study is needed to compare the species composition, richness, and soil nutrients of these two plantation activities to the natural Sal forest in the degraded Madhupur Sal forest in Bangladesh. Results: The analysis showed that in between the reforestation activities, the highest Shannon-Wiener index (1.79), evenness (0.60) and Simpson's index (0.79) were found in the agroforestry site compared to the woodlot plantation site. On the contrary, the highest species richness (n = 14), tree basal area (19.56 m² ha^-1), Margalef's index (1.96) were recorded in woodlot plantation than in the agroforestry site. We observed that at 0-15 cm depth, soil organic matter (2.39%), total nitrogen (0.14%), available phosphorous (62.67 ㎍ g^-1) and exchangeable potassium (0.36 meq/100 g) in agroforestry plots were significantly higher compared to other forest sites. At topsoil (15-30 cm depth), soil organic matter (1.67%) and available phosphorous (21.09 ㎍ g^-1) were found to be higher in agroforestry site. Conclusions: Both reforestation approaches improved soil function, although woodlot plantation had the higher species richness. Therefore, plantation activities by the sustainable implementation of these two practices are the best alternative to restore the biodiversity, richness and conserve soil fertility in the Madhupur Sal forest of Bangladesh.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.109-110
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• 2015

This paper presents a computational method that identifies an exact set of optimal overlap rates between critical activities to meet job site specific needs by using rework cost-slope. The procedures to compute the exact solution are provided in peudocode algorithm. The method is coded into Exact Concurrent Construction Scheduling system that allows practitioners to make more informed decision in accordance with the site-specific condition involved in the overlapping of critical activities. Test cases verify the validity of the computational method and the usability of the system.

• 디지털산업정보학회논문지
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• 제4권3호
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• pp.103-114
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• 2008

This study is to find a foundation of building customer's attachment to internet site and understand the structural cause and effect relationship between customer's attachment and trust ; Once being formated attachment to internet-site, become Trust on the internet-site. Empirical study have been carried out by using structural equation model to find those relationship and the result and its implication are following. First, Customer's self-image Congruence have an influence on attachment to internet site and as origin nature, secure attachment is also one of critical foundations of attachment to the site. Second, Customer's activities for community have an effect on the attachment significantly but interaction between customer and the site have tiny effect on love to the site. Third, the love to the site could be one of critical elements to perceive the trust to the site but only interested in the site wouldn't effect on the trust. Except for those elements mentioned above, as a foundation of building the attachment, interaction and self-image congruence have directly effect on the trust.

• BMB Reports
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• 제36권6호
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• pp.538-544
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• 2003

The hepatitis C virus (HCV) is a major causative agent of chronic hepatitis and hepatocellular carcinoma. The development of alternative antiviral therapies is warranted because current treatments for the HCV infection affect only a limited number of patients and lead to significant toxicities. The HCV genome is exclusively present in the RNA form; therefore, ribozyme strategies to target certain HCV sequences have been proposed as anti-HCV treatments. In this study, we determined which regions of the internal ribosome entry site (IRES) of HCV are accessible to ribozymes by employing an RNA mapping strategy that is based on a trans-splicing ribozyme library. We then discovered that the loop regions of the domain IIIb of HCV IRES appeared to be particularly accessible. Moreover, to verify if the target sites that were predicted to be accessible are truly the most accessible, we assessed the ribozyme activities by comparing not only the trans-splicing activities in vitro but also the trans-cleavage activities in cells of several ribozymes that targeted different sites. The ribozyme that could target the most accessible site identified by mapping studies was then the most active with high fidelity in cells as well as in vitro. These results demonstrate that the RNA mapping strategy represents an effective method to determine the accessible regions of target RNAs and have important implications for the development of various antiviral therapies which are based on RNA such as ribozyme, antisense, or siRNA.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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• pp.287-292
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• 1997

Recent economic growths have accelerating much construction activities of various infrastructures, such as Express railway, Long-span bridges, Multi-story Buildings and etc. Reinforcement steel corrosion to be inevitably caused under the progress of these construction activities have been on and off serious problems in the site, which could incur another tragedic accident to us suffering from safety-ignorance disease. Thus, it is strongly requested to develop probable innovative products which could remove corrosive materials on rebars and also protect steel corrosion of reinforced concrete structures in the construction site. Hydro-Seal and Steel-Seal could solve these problems currently faced with in the construction site. The objective of this research is to experimentally evaluated the effect of Hydro-Seal and Steel-Seal in reinforced concrete structures, of which usage might affect the bond strength between steel and concrete, long-term compressive strength of concrete, corrosion resistance and etc. Related test results show that appropriate dosage of Hydro-Seal and Steel-Seal in reinforced concrete structures didnot affect physical properties of reinforced concrete structures.

• 무역상무연구
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• 제41권
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• pp.205-234
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• 2009

The trade portal site is one of the innovative skills which makes it possible for trade companies to manage international trade activities more efficiently by using the newest information technology. Especially, trade portal site can be considerable help to small and medium-sized enterprises which have much difficulties in finding overseas buyers due to the lack of international marketing capabilities. This study attempts to present a comprehensive model about the determinants of e-Trust in domestic trade portal site and to suggest practical strategies for e-Trade. Therefore, a theoretical framework was presented by the literature review, and a empirical study was carried out through a questionnaire survey to those who have had experiences of visiting trade portal site. The empirical analysis had the following results. First, it reveals that reputation, web-site quality, transaction efficiency of the trade portal site have influence upon e-Trust dimension. On the other hand, perceived risk did not have significant relationship with e-Trust. Second, e-Trust had significant impact on willingness to depend on the trade portal site. And also, e-Trust had positive influence on performance of using which is measured by sales increase, information sharing, and synergy effect.

• 한국환경농학회지
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• 제27권2호
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• pp.133-138
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• 2008

Fire can affect microbial community structure of soil through altered environmental conditions, nutrient availability, and biotic source for microbial re-colonization. We examined the influence of fire on chemical properties and soil enzyme activities of soil for 10 months. We also characterized the soil microbial community structure through ester-linked fatty acid analysis(EL-FAME). For this study, we established five burned plots(1*1 m) and 5 unburned plots outside the margin of fire. Soil was sampled three soil cores in a each plots and composited for analysis at 1, 3, 5, 8, and 10 month after fire. The fire caused an increase in soil pH, exchangeable Ca, and Mg, organic matter, available $P_2O_5$ compared to unburned sites. The content of $NH_4-N$ in burned site was significantly higher than that of unburned site and this effect continued for 8 months after fire. There was no difference of $NO_3-N$ content in soil between burned and unburned site. Fire caused no change in acid phosphatase and arylsulfatase activities but $\beta$-glucosidase and alkaline phosphatase activities in burned site were increased compared to unburned site. Microbial biomass as estimated by total concentration of EL-FAMEs in burned sites was significantly higher than that of unburned sites at one month after fire. Burned site decreased the EL-FAMEs indicative of gram-positive bacteria and tended to increase the fatty acid associated with gram-negative bacteria at one and three months after fire. The sum of EL-FAME compound $18:2{\omega}6,9c$ and $18:1{\omega}9c$ as served fungal biomarkers was decreased in burned site compared to unburned site.