• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.80-80
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• 2015

만곡부가 연속적으로 발생하는 사행하천은 만곡의 영향으로 2차류가 발생한다. 이러한 2차류의 영향은 하상변동, 제방침식 등의 문제를 발생시켜 사행수로의 흐름특성을 분석하기 위한 많은 연구들이 진행되어 왔다. 하지만, 대부분의 연구들은 실규모 하천의 유속측정의 어려움, 측정이 가능한 시설 및 경제적 제한으로 인해 주로 실내실험에서 측정된 자료를 이용하여 분석을 수행하여 흐름조건이 상이한 실제 하천에서 적용성에 한계가 있어 왔다. 본 연구에서는 상세한 3차원 유속 측정이 가능한 최신 계측기기인 초음파도플러유속계(ADCP)를 활용하여 실제하천과 유사한 흐름 상태 및 지형을 재현한 한국건설기술연구원 안동하천실험센터의 사행도 1.2, 1.5, 1.7의 실규모 사행수로에서 횡단면 측정을 수행하였다. 또한 초음파지점유속계(ADV)를 사행도 1.2의 ADCP 측정 단면과 동일한 횡단면에서 측정하여 공간평균된 ADCP 유속자료를 이용한 흐름패턴 분석의 적용성을 검증하였다. 그 결과 공간평균된 ADCP 유속분포는 시간평균한 ADV 유속분포와 다소 크기의 차이는 발생하였지만 패턴은 매우 유사하게 나타났다. 따라서, 공간평균된 ADCP 유속분포를 이용하여 2차류에 의한 흐름패턴 분석을 수행하였다. 2차류 패턴은 만곡의 위치에 따라 매우 복잡한 형태로 나타났다. 2차류에 의한 최대유속선과 최대수심선의 발생위치를 분석한 결과, 만곡의 정점부를 기준으로 만곡 전인 유입부에서는 이격되고 만곡 후인 유출부에서는 유사한 경로를 나타내고 있었다. 이때의 2차류강도(Secondary Current Intensity; SCI)는 만곡의 정점부 부근에서 최대로 증가했다가 다시 감소하는 결과를 보였다.

• Journal of Environmental Impact Assessment
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• v.31 no.5
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• pp.334-342
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• 2022

The stringent air environment conservation act forced to build an indoor dome for coal storage. However, it causes some problems due to accumulation of fly ash and harmful substances inside. To solve this problem, this study analyzed the pattern of internal airflow and the amount of ventilation for an indoor coal yard. Overall, the airflow inside the indoor coal yard tended to move to the southwest facing the mountain. In addition, sea-breeze was blowing from the northern louver window facing the sea, where airflow was flowing in. The total flow rate flowing into the indoor coal yard was 918,691 m³/h, and the number of natural ventilation per hour was 0.6 times. Therefore, it is proposed to install a forced ventilation device at the location where internal air flow is concentrated.

• Journal of Korea Spatial Information System Society
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• v.12 no.1
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• pp.18-27
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• 2010

In u-GIS environment, GeoSensor environment requires that dynamic data captured from various sensors and static information in terms of features in 2D or 3D are fused together. GeoSensors, the core of this environment, are distributed over a wide area sporadically, and are collected in any size constantly. As a result, storage space could be exceeded because of restricted memory in DSMS. To solve this kind of problems, a lot of related studies are being researched actively. There are typically 3 different methods - Random Load Shedding, Semantic Load Shedding, and Sampling. Random Load Shedding chooses and deletes data in random. Semantic Load Shedding prioritizes data, then deletes it first which has lower priority. Sampling uses statistical operation, computes sampling rate, and sheds load. However, they are not high accuracy because traditional ones do not consider spatial characteristics. In this paper 'Pre-Filtering based Post Load Shedding' are suggested to improve the accuracy of spatial query and to restrict load shedding in DSMS. This method, at first, limits unnecessarily increased loads in stream queue with 'Pre-Filtering'. And then, it processes 'Post-Load Shedding', considering data and spatial status to guarantee the accuracy of result. The suggested method effectively reduces the number of the performance of load shedding, and improves the accuracy of spatial query.

• Korean Journal of Culture and Social Issue
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• v.8 no.1
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• pp.17-40
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• 2002

The purpose of this study is to investigate the differences in the traffic environments and driving behaviors in 5 regions of Korea. Data were collected through the survey research from 1387 passenger car drivers in 14 locations in Korea. The main findings of this research are as followings: First of all, There were significant differences in traffic environment factors(road topography, construction, road & safety facilities, pedestrian behaviors, surrounding drivers) among 5 regional areas. When we examined drivers factors, there were significant differences among 5 metropolitan areas on wearing seat belt, most of constructions related to drink driving, speed-limit violation. There were many differences in driving habits, intentions, behaviors including wearing seat belt, driving after drinking according to metropolitan area, and also in case of speed-limit violation and careless driving behavior. These results suggested that there are many differences in traffic environments and driver's behaviors among regional areas. These result suggests that traffic safety policy and practice should be prepared based upon the peculiarities of regional area. We discussed these resulte in terms of the regional traffic policy and the suggestions for future studies were added.

• Journal of Environmental Impact Assessment
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• v.29 no.1
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• pp.45-60
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• 2020

In the past, air pollution, water pollution and solid waste were very important items, but at present environmentally sound land use, ecosystem conservation and sustainable socio-economy have become very important in EIA. According to the consultation result of SEA and Small scale EIA during 2012~2019, most results are 'Conditional Agreement'. Especially EIA consultation results before 2016 were mostly (94.1 %) 'Agreement', but since 2017 most (87.4 %) are 'Conditional Agreement'. And the percentage of 'Non Agreement' have sharply increased from 0.3~0.6 % (during 2013~2016) to 1.3~3.1 % (during 2017~2019). In case there have been no change in EIA system and consultation techniques, the problems of inconsistency and unfairness could be raised. Therefore are urgently required researches on environmentally sound land use, ecosystem conservation and sustainable socio-economy which decide location feasibility assessment. The purpose of this study is to analyse the consultation cases of SEA, EIA, and Small scale EIA since 2012, and to identify key factors which result in the decision of nonagreement of development plans and development projects, and to suggest the improvements on EIA consultation based on land use regulation and environmental grade.

• Journal of Science and Technology Studies
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• v.19 no.3
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• pp.119-166
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• 2019

The risk of electromagnetic field(EMF) from power lines has been heavily disputed whenever high-voltage power line towers were built in South Korea. Local communities and civic groups had regarded burying the lines in the ground as an alternative to building power line towers. In 2014, however, when an elementary school science teacher reported the results of EMF measurements over the underground power lines to the Asian Citizens' Center for Environment and Health (ACCEH), the risk controversy over underground power lines took a whole new turn. The level of EMF from underground power lines turned out to be higher, and therefore more harmful than that from power line towers. In the debates that took place from then on over the EMF risk, ACCEH and NIER(National Institute of Environmental Research) presented conflicting topographies of EMF risk. This paper examines measuring practices of ACCEH and NIER by analyzing the measuring sites, measuring devices, and measuring heights chosen by each organization. This paper further examines how ACCEH and NIER mobilized various standards(EMF exposure limit, measurement guideline, categorization of carcinogens) differently. This controversy on the EMF from underground power lines of Seoul has raised concerns on the non-thermal effects of EMF in the long-term exposure and has led people to question whether burying the power lines is the safe alternative to building power line towers. Furthermore, this suggests conflicting answers on whether Seoul, where 90 % of transmission lines were already buried, is a safely managed place or not.

• Cross-Cultural Studies
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• v.51
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• pp.291-327
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• 2018

'Hyesung' and 'Jeilsun' are media that reveal the new searches of the Gaebyeoksa Publishing Company of the 1930s. However, studies in the past did not sufficiently analyze their significance. Furthermore, there are no analyses on how the critical minds of 'Hyesung' and 'Jeilsun' were linked to 'Gaebyeok', which continued publications in 1934. The 1930s when 'Hyesung' and 'Jeilsun' were published, was a time where the media of colonial Chosun was rapidly changing, and it was a time where literary magazines were increasing in quantity. In the 1930s, Gaebyeoksa attempted to actively respond to such changes reflected in the media. This was demonstrated through the publication of the new media 'Hyesung' and 'Jeilsun' and continuing publication of the 'Gaebyeok' magazine in 1935. This study analyzed the literary discourses shown in the magazines published by Gaebyeoksa in the 1930s based on 'Hyesung', 'Jeilsun', and the continued publication of 'Gaebyeok'. Through such analysis, this study examined how the magazines published by Gaebyeoksa perceived the culture and literature of colonial Chosun in the 1930s and in which direction it tried to reorganize this.

• Korean Journal of Construction Engineering and Management
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• v.10 no.1
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• pp.156-166
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• 2009

Residential land development projects are tending upwards recently. However, an indiscreet residential land development has tended to damage environment by destroying existing green lands and trees of target lands and generating many cut slopes with transformation of its topography. There are Prior Environmental Review(PER) for district designation and Environmental Impact Assessment(EIA) before approval on development plans. PER is implemented after developing a residential land development plan and EIA is implemented after completing a detail design. As the result, many of residential land development projects are passive to reduce potential environmental problems on the designated sites. Object of this study is to construct an evaluation system on alternatives in the early step of site designation for implementing residential land development projects with environment-friendly and sustainable way. For this, alternative evaluation model is constructed by using Fuzzy Inference and Analytic Hierarchy Process(AHP) method based on Environmental Evaluation Factors of residential land development project, which are proposed in the precedent research. If a decision maker evaluates environment damage by ten-point method, the point is transformed Environmental Performance(EP) by Fuzzy Inference, and then, applying weight that is already calculated by AHP method, Total Environmental Performance(TEP) is calculated. After all, an alternative with the highest TEP is selected as the best one. Using this evaluation system, more than two alternatives of residential land development project site, which can hold location appropriateness in the early under undecided land use plan, can be evaluated quantitatively. As environmental damages, which can be generated by implementing a residential land development project, can be detected in the early step, environmental damages can be removed or reduced at the source.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.1154-1158
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• 2007

현재 국내 하천에는 수많은 보가 존재하고 있으며, 하천에 설치된 보는 보 주변 지역에 많은 혜택을 제공한다. 보의 규모가 클 경우 소수력 발전을 위한 용도로 사용되거나, 선박 통행을 위한 수심 확보 목적으로 활용된다. 상수원으로서 농업용수와 생활용수를 공급하며, 홍수 시 상부 저수지를 홍수 조절을 위한 목적으로 활용되며, 지역 주민들에게 여가 활용의 기회를 제공한다. 이렇듯 하천에 설치되어 있는 보는 유용한 역할을 수행하지만 사용하고자 하는 용도가 없어지고, 노후화되어 보의 기능이 점차 약화되는 보들이 하천에 계속 남아있게 된다면, 필요 없이 하천을 막아 흐름을 정체시켜 결국 환경이나 생태적인 측면에서 커다란 손실을 가져오게 된다. 최근 농경지 도시화, 경작 방식의 변화, 취수시설물 통폐합, 시설 노후화 등으로 매년 수십 개 이상의 보가 폐기되고 있으나, 폐기된 보는 대부분 철거되지 않고 하천에 남아 여전히 문제를 발생시키고 있으며, 외국의 경우에는 이미 기능 및 용도를 상실한 보 철거는 하천 생태통로 복원 등의 목적을 위해 하천환경복원의 한 방법으로 널리 활용하고 있다. 특히 보의 기능 상실 여부는 단순한 시설물 노후 여부로 따지는 것이 아니라 본래의 기능을 상실하였을 경우에는 시설물이 노후화되지 않았더라도 적극적으로 철거하고 있다. 본 연구는 보 철거를 통한 하천생태통로 복원 기술 개발을 위한 연구의 일환으로 기능을 상실한 보 철거를 위한 보 철거 선정 체계에 대한 시안을 제시하고자 한다. 철거 대상 보 선정을 위해서는 보 관리주체 및 보 주변지역에 거주하는 주민의 역할이 중요하며, 이에 따라 보 철거 선정 체계는 보 철거를 위해서 보 주변 지역 거주민을 설득하며, 하천의 환경 개선을 위한 합리적인 대안 제시를 목적으로 하고 있다. 선정 체계를 바탕으로 주민 협의 및 대안 제시를 통해 결정된 대상 보는 선정 체계 안에서 보 철거 영향 판단 절차에 따라서 보 철거로 인한 수문, 수리, 지형, 수질, 생태 영향을 판단하게 되며, 이와 더불어 사회 경제적인 영향을 평가하게 된다. 평가결과에 따라서 보를 완전히 철거하거나 다른 대안을 고려하여 보를 부분적으로 철거하거나 개량하게 된다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.41 no.2
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• pp.269-276
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• 2016

Internet of Things (IoT) is based on wireless networks being able to connect things and people on a large scale. In the IoT environment, reliable broadcast plays an important role to distribute data to a large number of devices. Energy harvesting from a surrounding environment is a key technique to achieve a sustainable IoT network. In IoT networks, a problem of transmission errors and energy shortage should be mitigated for reliable broadcast. In this paper, we propose an energy-efficient and reliable broadcast method to consider packet errors and energy consumption in the environment where a large number of nodes are connected. The proposed scheme can improve data restoration probability by up to 15% and reduce energy consumption by up to 17%.