• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.785-789
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• 2006

유역 수자원의 효율적인 관리 및 배분을 위해서는 세밀한 강우-유출관계의 규명이 무엇보다 중요하다. 이를 위해서는 먼저 하천 유출지점의 정확한 유량정보가 획득되어야 하며, 장기간에 걸쳐 신뢰성 있는 유량자료의 확보는 더욱 중요한 사항이다. 본 연구에서는 하천에서 관측된 유량자료를 장기간(1983년${\sim}$2004년)에 걸친 유출성분으로 분리하는 기법을 활용하여 제어지점의 유출량을 검증하였다. 유량자료를 출구지점의 관측유량$(Q_{ob})$을 회귀수$({\alpha}Q_e)$, 상류유입량$(Q_{up})$ 및 관측강우-유출량$({\beta}Q_{Rain})$의 성분으로 구분하여 산정하는 방식으로 유출량을 추정하였다. 여기서, 회귀수$({\alpha}Q_e)$란 유역 및 하도내 용수이용량의 회귀수, 상류유입량$(Q_{up})$은 상류 유출 제어지점의 관측유량으로 대청댐 방류량, 관측강우-유출량$({\beta}Q_{Rain})$은 유역내 강우에 의한 자연유출량이다. 여기서 사용된 수문기초자료는 대청댐 방류량, 대전 및 청주권 취수량, 강우에 의한 자연유출량, 공주관측유량 등으로 각 성분별로 생성된 일자료를 이용하여 공주지점의 월별, 분기별, 년도별 유출량을 산정하였다. 이 결과는 금강유역에 이미 구축되어있는 SSARR모형을 기반으로 한 RRFS(Rainfall Runoff Forecasting System, 유출예측 시스템)의 결과 및 관측치와 비교되었다. 계산결과 RRFS에 의한 유출량과 대청-공주구간의 유출성분분리에 의한 유출량은 관측값과 전반적으로 근사함을 확인하였으며, 검증지점의 정확한 유출율을 산정할 수 있다면, 관측자료의 연속성 및 신뢰도를 파악하는 척도를 제공할 수 있을 것으로 판단된다.측결과 있는 대상유역에 대한 적용이 요구된다.-Moment 방법에 의해 추정된 매개변수를 사용한 Power 분포를 적용하였으며 이들 분포의 적합도를 PPCC Test를 사용하여 평가해봄으로써 낙동강 유역에서의 저수시의 유출량 추정에 대한 Power 분포의 적용성을 판단해 보았다. 뿐만 아니라 이와 관련된 수문요소기술을 확보할 수 있을 것이다.역의 물순환 과정을 보다 명확히 규명하고자 노력하였다.으로 추정되었다.면으로의 월류량을 산정하고 유입된 지표유량에 대해서 배수시스템에서의 흐름해석을 수행하였다. 그리고, 침수해석을 위해서는 2차원 침수해석을 위한 DEM기반 침수해석모형을 개발하였고, 건물의 영향을 고려할 수 있도록 구성하였다. 본 연구결과 지표류 유출 해석의 물리적 특성을 잘 반영하며, 도시지역의 복잡한 배수시스템 해석모형과 지표범람 모형을 통합한 모형 개발로 인해 더욱 정교한 도시지역에서의 홍수 범람 해석을 실시할 수 있을 것으로 판단된다. 본 모형의 개발로 침수상황의 시간별 진행과정을 분석함으로써 도시홍수에 대한 침수위험 지점 파악 및 주민대피지도 구축 등에 활용될 수 있을 것으로 판단된다. 있을 것으로 판단되었다.4일간의 기상변화가 자발성 기흉 발생에 영향을 미친다고 추론할 수 있었다. 향후 본 연구에서 추론된 기상변화와 기흉 발생과의 인과관계를 확인하고 좀 더 구체화하기 위한 연구가 필요할 것이다.게 이루어질 수 있을 것으로 기대된다.는 초과수익률이 상승하지만, 이후로는 감소하므로, 반전거래전략을 활용하는 경우 주식투자기간은 24개월이하의 중단기가 적합함을 발견하였다. 이상의 행태적 측면과 투자성과측면의 실증결과를 통하여 한국주식시장에 있어서 시장수익률을 평균적으로 초과할 수 있는 거래전략은 존재하므로 이러한 전략을 개발 및 활용할 수 있으며, 특히, 한국주식시장에 적합한 거래전략은 반전거래전략이고, 이 전략의 유용성은 투자자가 설정한 투자기간보다 더욱 긴

• The Journal of the Korea institute of electronic communication sciences
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• v.8 no.6
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• pp.863-871
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• 2013

Recently application of open protocols and external network linkage to the national critical infrastructure has been growing with the development of information and communication technologies. This trend could mean that the national critical infrastructure is exposed to cyber attacks and can be seriously jeopardized when it gets remotely operated or controlled by viruses, crackers, or cyber terrorists. In this paper virtual Honeynet model which can reduce installation and operation resource problems of Honeynet system is proposed. It maintains the merits of Honeynet system and adapts the virtualization technology. Also, virtual Honeynet model that can minimize operating cost is proposed with data analysis and collecting technique based on the verification of attack intention and focus-oriented analysis technique. With the proposed model, new type of attack detection system based on virtual Honeynet, that is Cybertrap, is designed and implemented with the host and data collecting technique based on the verification of attack intention and the network attack pattern visualization technique. To test proposed system we establish test-bed and evaluate the functionality and performance through series of experiments.

• Korean Journal of Remote Sensing
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• v.38 no.6_1
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• pp.1191-1205
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• 2022

Particulate matter(PM) among air pollutants with complex and widespread causes is classified according to particle size. Among them, PM_2.5 is very small in size and can cause diseases in the human respiratory tract or cardiovascular system if inhaled by humans. In order to prepare for these risks, state-centered management and preventable monitoring and forecasting are important. This study tried to predict PM_2.5 in Seoul, where high concentrations of fine dust occur frequently, using two ensemble models, random forest (RF) and extreme gradient boosting (XGB) using 15 local data assimilation and prediction system (LDAPS) weather-related factors, aerosol optical depth (AOD) and 4 chemical factors as independent variables. Performance evaluation and factor importance evaluation of the two models used for prediction were performed, and seasonal model analysis was also performed. As a result of prediction accuracy, RF showed high prediction accuracy of R² = 0.85 and XGB R² = 0.91, and it was confirmed that XGB was a more suitable model for PM_2.5 prediction than RF. As a result of the seasonal model analysis, it can be said that the prediction performance was good compared to the observed values with high concentrations in spring. In this study, PM_2.5 of Seoul was predicted using various factors, and an ensemble-based PM_2.5 prediction model showing good performance was constructed.

• Ecology and Resilient Infrastructure
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• v.8 no.2
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• pp.79-87
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• 2021

Because active interactions occur among vegetation, hydrology, and geomorphology in riparian systems, any changes in one of these factors can significantly affect the other two. In this study, we evaluated these interactions at four sites (two in Gajeong and two in Hahan) along the Seomjin-gang River that was substantially devastated by an extreme flood in 2020. We examined the relationship between the riparian vegetation and the hydraulic characteristics of the flood using remote sensing, hydraulic modeling, and field surveys combined. The evaluation results showed that the floods caused a record-breaking rise of up to 43.1 m above sea level at the Yeseong-bridge stage gauge station (zero elevation 27.4 m) located between the Gajeong and Hahan sites, with the shear stress being four times higher in Hahan than in Gajeong. Additionally, the water level during the flood was estimated to be a maximum of 1 m higher depending on the location in the presence of riparian plants. Furthermore, both sites underwent extensive biological damage due to the flood, with 78-80% loss in vegetation, with preferential damage observed in large willow species, compared to Quercus acutissima. The above findings imply that all plant species exhibit different vulnerabilities towards extreme floods and do not induce similar behavior towards events causing a disturbance. In conclusion, we developed strategies for effectively managing riparian trees by minimizing flood hazards that could inevitably cause damage.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.5
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• pp.644-652
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• 2007

In this study, we examined family history of chronic diseases, food group intake and physical activity in $5^{th}\;and\; 6^{th}$ grade elementary school children. Food group intake was compared with the KDRI food guides for children. The measurements of daily physical activity, television viewing, computer use, and daily servings of five food groups, including grains, meats, dairy products, fruits, and vegetables, were based on child and parent self-reports. As indices of obesity, the obesity index(%) and BMI(Body Mass Index) were used. The results were as follows. In boys, 83.2% were normal weight with 7.4% slightly obese, 7.4% moderately obese, and 2.0 were highly obese while the percentages of normal and slightly obese in girls were 89.9% and 6.2% respectively (p<0.05). The boys had more hours of daily physical activity(p<0.05) and more hours of computer usage(Internet searching or games)(p<0.05) than the girls. Slightly over 50% of the subjects met the daily recommended servings of grains, dairy products, fruits, and vegetables according to the KDRI food guides. However, only 26% of boys and 27% of girls met the recommended daily servings of protein foods such as meats, beans, and eggs. Thirty two percent(32%) of girls consumed high fat snacks everyday while 32% consumed high sugar snacks every day. The girls consumed more vegetables(p<0.05) and more high sugar snacks(p<0.05) than the boys. The children with family histories of obesity showed greater obesity rates(p<0.05) and sedentary lifestyles(p< 0.05) than those children without a family history of obesity. Children with family histories of high blood pressure consumed more sewings of vegetables and high fat snacks than the controls(p<0.05). The children with family histories of obesity consumed more high sugar or high fat snacks than the controls(p<0.05).

• Korean Security Journal
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• no.37
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• pp.325-354
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• 2013

The concept of national security and the fundamental system for crisis management have departed from traditional methods and the importance of a national critical infrastructure crisis management has been emphasized. A national critical infrastructure crisis means a situation where human resource, material and functional system that may have a material effect on the critical functions of the government, the vitality and integrity of society, national economy and the safety of the public becomes disabled due to causes such as terrorism or major disasters. Although North Korea had been subject to numerous rounds of negotiations and sanctions as it continually developed nuclear weapons since the 1960s, it has also showed off its nuclear armaments through successful nuclear testings and missile launches. As the development and threat of North Korea's weapons of mass destruction becomes more noticeable and the range of its risk expands, this study focuses on the potential for an absence of leadership for national crisis management where the country's leadership, which should serve the critical role and function of handling national crises, becomes completely destroyed by the unexpected initial attacks by North Korea. As a result, the purpose of this study is to propose safety measures for the country's leadership in preparation for North Korea's threat of nuclear weapons by examining the concept and degree of risk of weapons of mass destruction with a focus on nuclear weapons, analyzing the substance of the threat of North Korean nuclear weapons and evaluating such threat. In conclusion, first, to ensure the normal functioning of a national crisis management system in the event of a national crisis, we must seek safety measures that conform to the scope and succession order of the leadership of the national crisis management for an Enduring Constitutional Government (ECG) and the Continuity Of Operations (COOP). Second, in the event of a national ceremony, the gathering of the country's leadership all together in an open place should be avoided. In unavoidable circumstances, the next in rank that will act on behalf of the current leader should be designated and relevant safety measures should be taken. Third, during time of peace, in preparation for national crises, the scope of protection for the country's leadership should be prescribed and specific security and safety measures should be implemented. Fourth, the succession order for acting president in the case of the death of the president pursuant to Articles 71 and 26(1) of the National Government Organization Act should reconsidered to see whether it is a reasonable provision that takes into consideration a national crisis management that corresponds to the threat of North Korean nuclear weapons and weapons of mass destruction. Pursuant to the Basic Guidelines for National Crisis Management set out under Presidential Directive No. 229, the Korean government is currently operating a case-by-case "crisis management standard manual" and its sub-manuals and has also prepared the Presidential Security Service's security and safety measure regulations regarding the acting president. Therefore, the Korean government should actualize the above points in the case-by-case crisis management standard manual and security and safety measure regulations regarding the acting president to implement and legislate them.

• Korean Journal of Food Science and Technology
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• v.41 no.4
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• pp.392-398
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• 2009

This study identified risk factors of cross-contamination of foodborne pathogens and established a good agricultural practice (GAP) system for an agricultural products processing center (APC) for perilla leaves. All samples were collected before and after a standard work shift at the APC, while perilla leaves were also collected after each step in the APC. In addition, the workers and their surroundings were sampled by swabbing. The total plate count (TPC) and coliform count in the water samples increased significantly (p<0.05) to 3.36 and 1.73 log CFU/mL after work, respectively. However, no Escherichia coli and Listeria monocytogenes were detected. The bacterial populations of the workers and their surroundings did not differ significantly (p${\geq}$0.05) before and after work. However, Staphylococcus aureus (<1.66 log CFU) was detected at a high rate (13-50%) in the basket, packing table, gloves and cloth. Although perilla leaves passed through the washing steps, the TPC and coliform bacterial populations on the final products were higher (p${\geq}$0.05) than those of unwashed perilla leaves, which indicates that the washing system was not functioning properly. Accordingly, a GAP system with a better washing system should be employed at this facility.

• Journal of Nutrition and Health
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• v.47 no.6
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• pp.403-415
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• 2014

Purpose: This study was conducted in order to investigate the nutrient and food intake status, and dietary quality in Korean adults according to abdominal obesity based on waist circumference. Methods: We analyzed data from the combined 2010~2012 KNHANES (Korean National Health and Nutrition Examination Survey). The analysis included 6,974 adults aged 40 to 64 years. In this study, according to abdominal obesity based on waist circumference (male ${\geq}$ 90 cm, female ${\geq}$ 85 cm), we classified the subjects into the obesity group (male, n = 775, female, n = 1,113) and control group (male, n = 2,038, female, n = 3,048). The nutrient and food group intake, ND (nutrient density), NAR (nutrient adequacy ratio), MAR (mean adequacy ratio), INQ (index of nutritional quality), DDS (dietary diversity score), and DVS (dietary variety score) were analyzed using data from the 24-recall method. Results: For male, no significant difference in quality index of the diet was observed between the obesity group and the normal group. In female, in diet quality (ND, NAR, and INQ), vitamin $B_2$ (ND, NAR, and INQ) calcium (NAR), phosphorous (ND, INQ) and potassium (ND) of the obesity group was significantly lower than those of the control group. DDS and DVS in the obesity group (3.57, 30.95) were significantly lower than those of the control group (3.68, 32.84) (p = 0.0043, 0.0002). DVS (DVS ${\geq}$ 39.9) showed association with lower risk of waist obesity in a logistic regression model after adjustments for multiple confounding factors including age, education, income, alcohol intake frequency, smoking, physical activity, energy intake, and body mass index (OR: 0.616, 95% CI: 0.420-0.903). Conclusion: In conclusion, females with abdominal obesity had lower micronutrient intake quality, DVS than those of the control group. In Korean females, food intake variety can adversely affect waist circumference.

• Journal of Internet Computing and Services
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• v.17 no.6
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• pp.123-131
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• 2016

Process mining in big data environment utilize a number of data were generated from the business process. It generates lots of knowledge and insights regarding implementation and improvement of the process through the event log of the company's enterprise resource planning (ERP) system. In recent years, various research activities engaged with the audit work of company organizations are trying actively by using the maximum strength of the mining process. However, domestic studies on applicable sales auditing system for the process mining are insufficient under big data environment. Therefore, we propose process-mining methods that can be optimally applied to online and traditional auditing system. In advance, we propose continuous monitoring information system that can early detect and prevent the risk under the big data environment by monitoring risk factors in the organizations of enterprise. The scope of the research of this paper is to design a pre-verification system for risk factor via practical examples in sales auditing. Furthermore, realizations of preventive audit, continuous monitoring for high risk, reduction of fraud, and timely action for violation of rules are enhanced by proposed sales auditing system. According to the simulation results, avoidance of financial risks, reduction of audit period, and improvement of audit quality are represented.

• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.3
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• pp.277-291
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• 2020

Shield TBM is a tunnelling method that has a wider range of applications in the poor ground condition compared to conventional tunnels (Drill and Blast). Currently, a 13.3 m large-diameter slurry shield TBM is preparing for construction to pass under the Han River. Shield TBM is divided into slurry and EPB shield TBM, and management items during construction are different depending on each characteristic. In this paper, the equipment type, origin, application case and trouble case were analyzed for slurry shield TBM, which is mainly constructed in soft ground. In addition, 2D and 3D model tests were conducted on the condition of soil depth for the possibility of slurry leakage into front of the equipment, with appropriate chamber pressure. Based on this paper, it proposed to provide basic and reference data for proper excavation surface pressure and chamber pressure during construction of slurry shield TBM under soft ground conditions, and proposed measures to minimize stability and environmental decline due to slurry ejection.