• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.434-440
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• 2011

In order to establish the guidance of management and safe use hazard substance, trend analysis of hazard substance in/on agricultural products reported by press for 5 years (2005-2009) was performed. Data for the analysis collected from the articles about hazard substances from web portals, newspapers and so on. The mostly detected harmful factors in/on agricultural products were pesticides residue and heavy metals by the reports by press for last 5 years. The number of detected pesticides was slightly increased from 14 to 34 through the passage of time but the number of cases reported by press was not increased. On the other hand, the number of accidents and reports related to heavy metals were highly increased from 3 to 13 and 42 to 112, respectively. 65 pesticides including chlorpyrifos were detected in domestic agricultural products for the 5 years. Frequently detected pesticides were chlorpyrifos, endosulfan, carbendazim, azoxystrobin, and procymidone. Pesticide residues were repeatedly detected on green vegetables such as a green perilla leaf, a lettuce, a leek, and spinach among crops.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.14 no.6
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• pp.77-90
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• 2015

An increasing number of vehicles is causing various traffic problems such as chronic congestion of highways and air pollution. Local governments have been managing traffic by constructing systems such as Intelligent Transport Systems (ITS) and Advanced Traffic Management Systems (ATMS) to relieve such problems, but construction of an infrastructure-based traffic system is insufficient in resolving chronic traffic problems. A more sophisticated system with enhanced operational management capabilities added to the existing facilities is necessary at this point. As traffic patterns of the urban traffic flow is time-specific due to the different vehicle populations throughout the time of the day, a local network-wide signal operation plan that can manage such situation-specific traffic patterns is deemed to be necessary. Therefore, this study is conducted for the purpose of establishment of a plan for contextual signal control management through signal optimization at the network level after setting the Frame Signal in accordance to the traffic patterns gathered from the short-term traffic forecast data as a means to mitigate the problems with existing standardized signal operations.

• Journal of the Korean earth science society
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• v.23 no.5
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• pp.416-423
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• 2002

The concentrations of dimethylsulfide (DMS) and carbon disulfide (CS$_2$) were measured concurrently with relevant environmental parameters at Kosan, Cheju during Apr 2001. Results of our analysis indicate that the combined temporal variations of both DMS and CS$_2$ record three distinctible patterns that are separable from each other. For instance, DMS behaved very similarly to CS$_2$ during the 1st (5${\sim}$18 Apr) and 3rd period (23${\sim}$26 Apr). The pronouncingly high concentration of CS$_2$ was maintained during the first period, but DMS values peaked mostly during the third period. It was furthermore striking to find that changes in DMS levels occurred in an opposite direction relative to CS$_2$ during the 2nd period. Although most of these variabilities appear to be associated with the interaction of source/sink processes and the air parcel movement, certain aspects of their behavior are found to be highly complicated enough to account for.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.35 no.4
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• pp.88-97
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• 2017

The purpose of this study was to identify the development and transition of the Original landscape(始景觀) of Oeam Village based on the landscape that changes over time and the relevant factors and the following summarizes the findings: First, Original landscape perceived by the ancestors of Korea was identified in the description of topography and landscape of Oeam Village mentioned in various literature such as "Oeamgi(巍巖記)" and topography was analyzed to identify that the natural waters that flew before Oeam Village was formed aligned with the artificial waterway inside the village. Second, the landscape of Oeam Village was classified by characterized events: (1) expansion of the tribal town of the Yi Family of Yean, (2) stagnancy where the villagers formed an organic relationship without much change to the landscape, (3) the biggest change to the landscape by national policies, and (4) preservation and use of tourism resources based on preservation of cultural heritage. Third, the center of village moved from the east of village to the west of village. In the past, the east of village provided agricultural functions for the development and expansion of village. The center later shifted to the entrance to the west of village under the influence of industrialization and tourism. Further studies would be necessary to clarify the authenticity of resources through additional literature for better understanding of the past of Oeam Village and the transition of the village's landscape elements and the comparison of their characteristics could be possible topics for future studies.

• Proceedings of the Korea Water Resources Association Conference
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• 2019.05a
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• pp.413-413
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• 2019

하천과 호수에서 남조류의 이상 과잉증식 문제(이하 녹조문제)는 담수생태계의 생물다양성을 감소시키며, 음용수의 이취미 원인물질을 발생시켜 물 이용에 장해가 된다. 또한 독소를 생산하는 유해남조류가 대량 증식할 경우에는 가축이나 인간의 건강에 치명적 해를 끼치기도 한다. 그 동안 국내에서 녹조문제는 댐 저수지와 하구호와 같은 정체수역에서 간헐적으로 문제를 일으켰으나, 4대강사업(2010-2011)으로 16개의 보가 설치된 이후 낙동강, 금강, 영산강 등 대하천에서도 광범위하게 발생되고 있어 중요한 사회적 환경적 이슈로 대두되었다. 한편, 대하천에 설치된 보 구간에서 빈번히 발생하는 녹조현상의 원인에 대해서는 전 지구적 기온상승에 따른 기후변화의 영향이라는 주장과 유역으로부터 영양염류의 과도한 유입, 가뭄에 따른 유량감소, 보 설치에 따른 체류시간 증가 등 다양한 의견이 제시되고 있으나, 대상 유역과 수체의 특성에 따라 녹조 발생의 원인이 상이하거나 또는 다양한 요인이 복합적으로 작용하기 때문에 보편적 해석(universal interpretation)이 어려운 것이 현실이다. 따라서 각 수계별, 보별 녹조현상에 대한 정확한 원인분석과 효과적인 대책 마련을 위해서는 집중된 실험자료와 데이터마이닝 기법에 근거로 한 보다 과학적이고 객관적인 접근이 이루어져야 한다. 본 연구에서는 2012년 보 설치 이후 남조류에 의한 녹조현상이 빈번히 발생하고 있는 낙동강 4개보(강정고령보, 달성보, 합천창녕보, 창녕함안보)를 대상으로 집중적인 현장조사와 실험분석을 수행하고, 수집된 기상, 수문, 수질, 조류 자료에 대해 통계분석과 다양한 데이터모델링 기법을 적용하여 보별 남조류 우점 환경조건과 이를 제어하기 위한 주요 조절변수를 규명하는데 있다. 연구대상 보 별 수질과 식물플랑크톤의 정성 및 정량 실험은 2017년 5월부터 2018년 11월까지 2년에 걸쳐 실시하였으며, 남조류 세포수 밀도와 환경요인과의 상관성 분석을 실시하고, 단계적 다중회귀모델(Step-wise Multiple Linear Regressions, SMLR), 랜덤포레스트(Random Forests, RF) 모델과 재귀적 변수 제거 기법(Recursive Feature Elimination using Random Forest, RFE-RF)을 이용한 변수중요도 평가, 의사결정나무(Decision Tree, DT), 주성분분석(Principal Component Analysis, PCA) 기법 등 다양한 모수적 및 비모수적 데이터마이닝 결과를 바탕으로 각 보별 남 조류 우점 환경요인을 종합적으로 해석하였다.

• Korean Journal of Soil Science and Fertilizer
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• v.32 no.4
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• pp.357-364
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• 1999

This study measures the influence of grass cover on water use and shoot growth of apple trees growing under different soil water regimes in temperate climate conditions and evaluates monthly crop coefficients of such conditions during four months of the growing season in 1995. To do so, double pot lysimeter experiments of 3-year-old Fuji' apple (Males domestica Borkh.) trees under a transparent rain shield were designed and installed. Trees were triplicate under three soil water regimes: (A) drip-irrigation at -50 kPa of soil matric potential (IR50). (B) drip-irrigation at -80 kPa of soil matric potential (IR80), and (C) constant shallow water table at 0.45 m below the soil surface (WT45). In each treatment, two soil surface conditions were tested: the soil surface bare, and covered with turf grasses. Mean monthly water use increased with increasing soil matric potential for drip irrigation and was greatest in the WT45 treatment. Monthly crop coefficients increased linearly in time for drip-irrigated apple trees ($r^2$ values of $0.953^{***}$ for turf grass-covered system and of $0.862^{***}$ for bare surface system), while those obtained in the WT45 treatment fluctuated, Duncan's multiple range tests for shoot growth showed that grass-covered IR50 was most favorable to apple trees. while bare surface waterlogged situation was most adverse at least in part due to a lack of oxygen in the root zone. Mid-season leaf Kjeldahl-N was higher in drip-irrigated apple trees than in WT45 trees, while soil Kjeldahl-N was not different irrespective of treatments.

• The Journal of the Korea Contents Association
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• v.21 no.9
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• pp.12-23
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• 2021

This study organizes policy tasks currently being promoted by the government to revitalize the domestic VR and AR industries, which are evaluated to be stagnant compared to major overseas countries, and aims to derive priorities through analysis of an AHP survey for experts in the VR/AR field, and to seek countermeasures based on the analysis results. As a result of classification based on various previous studies, press releases, and policy data, it was divided into 5 major categories and 16 sub-categories: technical issues, awareness improvement, legal/institutional improvement, government support, and manpower development. As a result of the AHP analysis, in the major category, the "government support" appeared as the top priority policy task, followed by the "manpower development". In the sub-categories, "training new manpower" was the most important policy implementation task, followed by "enhancing technological competitiveness". This study is meaningful in that it selects and presents prioritized policy tasks that clearly reflect the position and perspective of the industry on the policy-making situation exposed to the limitations of time and resources, while also presenting practical improvement plans.

• Journal of the Korean GEO-environmental Society
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• v.22 no.3
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• pp.31-35
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• 2021

The expansion joints installed on the bridge for the accommodation of expansion and contraction of the supper structure are essential members of the bridge. However, the expansion joints are deteriorated over time and the waterproof function weakens, causing rainwater to penetrate and deteriorate the structure. In order to solve the traffic congestion caused by frequent replacement of the old expansion joints along with the deterioration of the structure, a post-integrated abutment bridge in which the existing expansion joints are removed and replaced with reinforced concrete link connection has been applied to highway bridges since 2016. After the post-integrated abutment method was applied, it was partially applied to bridges in which the superstructure and abutment were jammed. In this study, the causes of problems that may occur when the post-integrated abutment method is applied to the jammed bridge were analyzed numerically. It was analyzed that damage occurred in the link connection part. Based on the results of this study, the application condition for the post-integrated abutment method is reinforced as it is not possible to apply the post-integrated abutment method to bridges are already jammed.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.3
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• pp.1-19
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• 2021

The domastic hard shoulder running(HSR) System has been gradually expanding since its initial implementation in September 2007 with the aim of increasing capacity and resolving congestion. Hard Shoulder is used as a space for driver's visual comfort and a place for vehicles to evacuate in case of emergency, but it is replaced by a space for driving when the HSR System is implemented. Therefore, it was intended to determine the improvement effect before and after implementation of the HSR system through safety analysis and mobility analysis. The safety analysis analyzed the impact of traffic accidents by comparing HSR sections and similar sections. The mobility analysis was to determine the improvement effect by quantifying the speed and traffic volume changes before and after HSR System implementation. According to safety yanalysis, there is no effect of reducing traffic accidents when implementing the HSR System. In mobility analysis, the implementation of the HSR System significantly improved the speed of traffic during peak hours and significantly reduces slow and delay hours.

• Journal of the Korean Society for Library and Information Science
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• v.56 no.3
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• pp.27-46
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• 2022

Today, public libraries are contributing deeply to our society by strengthening their ability and services to identify and respond to users' needs through various programs. However, it is difficult to find a study that analyzed the research status of public library programs or changes over time. Therefore, for the purpose of systematically grasping research trends in the field of overseas public library programs, an intellectual structure analysis based on keyword profiling was performed. Specifically, subject terms analysis, network analysis and cluster analysis, and analysis by period/year were performed based on the controlled keywords (subject terms) of journal articles papers searched in the LISTA database. As a result, first, it was found that 9 subjects corresponding to all global/hot/local topics are leading the research in the field of overseas public library programs. Second, five research areas in the field of overseas public library programs(cultural programs, outreach programs, activity programs, public services, community) could be visualized and clearly identified. Third, research in the field of overseas public library programs began in earnest in the late 1990s and was active from the mid-2000s to the early 2010s, and after that, it was found to be somewhat stagnant until recently. This study is the result of specifically identifying research trends on programs that recently emerged as a major task of public libraries, and can be used as basic data and prior knowledge to explore the development direction of public library programs in the future.