• KSCE Journal of Civil and Environmental Engineering Research
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• v.44 no.3
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• pp.329-336
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• 2024

In the case of multi-function weirs installed in Korea, the free hydraulic jump or the submerged hydraulic jump is occurred depending on the height of the gate opening and the tailwater level when the sluice gate of the movable weir is partially opened. In this study, the submerged hydraulic jump for the flows under the sluice gate were simulated and the mean flow, turbulence statistics, and relative water depth are investigated using numerical simulation. For numerical simulation, the unsteady Reynolds-averaged Navier-Stokes equation, volume of fluid method, and k-ωSST turbulence model were used. The numerical model was validated using the results of other researchers' previously performed experiments, and it was investigated that the numerical model appropriately simulates the two-phase flow in the hydraulic jump. In addition, the distribution of mean flow, turbulence statistics, and the length of recirculation region was investigated.

• Journal of the Korea Society of Computer and Information
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• v.29 no.10
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• pp.121-128
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• 2024

Demand forecasting is a critical element of revenue management in the tourism industry. Since the 2010s, with the globalization of the tourism industry and the increase of different forms of marketing and information sharing, such as SNS, forecasting has become difficult due to non-linear activities and unstructured information. Various forecasting models for resolving the problems have been studied, and ML models have been used effectively. In this study, we applied the feature selection technique (NSGA3) to time series models and compared their performance. In hotel demand forecasting, it was found that the TCN model has a high forecasting performance of MAPE 9.73% with a performance improvement of 7.05% compared to no feature selection. The results of this study are expected to be useful for decision support through improved forecasting performance.

• The Journal of the Korea institute of electronic communication sciences
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• v.19 no.5
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• pp.903-910
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• 2024

Complex semantic segmentation tasks are primarily performed in server environments equipped with high-performance graphics hardware such as GPUs and TPUs. This cloud-based AI inference method operates by transmitting processed results to the client. However, this approach is dependent on network communication and raises concerns about privacy infringement during the process of transmitting user data to servers. Therefore, this paper proposes a Generalized On-Device Framework for Semantic Segmentation that can operate in mobile environments with high accessibility to people. This framework supports various semantic segmentation models and enables direct inference in mobile environments through model conversion and efficient memory management techniques. It is expected that this research approach will enable effective execution of semantic segmentation algorithms even in resource-constrained situations such as IoT devices, autonomous vehicles, and industrial robots, which are not cloud computing environments. This is expected to contribute to the advancement of real-time image processing, privacy protection, and network-independent AI application fields.

• The Journal of the Korea institute of electronic communication sciences
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• v.19 no.5
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• pp.941-950
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• 2024

This study employed network analysis techniques to examine the relationships between spatiotemporal factors associated with crimes in public restrooms, drawing on diverse relevant data sources. We then evaluated the relative importance of these factors in crime occurrence. Variables related to crime incidence were identified, and their interconnectedness was assessed for network analysis, resulting in a data-driven network model with complex relational structures. The network model contributed to calculating the weight of each factor and identifying key elements. The location of public restrooms, usage time, surrounding environment, and facility conditions emerged as crucial factors in crime occurrence, with lighting quality and local security status showing high weightings. These findings can be utilized to prioritize interventions in public restroom design and management to enhance safety. The network analysis methodology demonstrated its potential in proposing crime prevention measures for public spaces, including restrooms, and contributing to the creation of safer public environments.

• Korean Journal of Environment and Ecology
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• v.28 no.5
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• pp.523-530
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• 2014

One juvenile raptor which was not able to be identified due to its head damage was discovered on a roadside in Janggok-ri, Jori-eup, Paju on 28th June, 2011. The species was identified by DNA barcoding. After polymerase chain reaction (PCR) of the mitochondrial cytochrome c oxidase subunit I gene (COI), we obtained 695 bp sequences. We analyzed the obtained COI sequence with similar sequences from the BOLD systems and BLAST of the NCBI Genbank, and discovered that its sequence showed 100 % similarity values with the one of the five gray-faced buzzards which were previously researched. In addition, it was confirmed to be a female through sex determination using DNA. Such results are important information as it confirms the breeding of the gray-faced buzzards for the first time in 43 years since its breeding was last recorded in 1968, in Paju. Wildlife rescue center needs to work with adjacent consigned registration and preservation institutions when carcass of wild animals is collected or DNA samples are obtained for more accurate both species and sex identification through a systematic management system in the future. Furthermore, the obtained DNA sample of the gray-faced buzzard and COI gene, DNA barcode, could be used as reference standards for similar researches in the future.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.130-134
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• 2006

본 연구의 목적은 하천 복원과 관리에 필수적인 하천의 특성 분석 및 물순환 분석시스템 구축에 있다. 연구 대상지역으로 최근 하천의 생태 기능 회복을 위해 도심생태하천조성 사업이 추진되고 있는 대전 3대 하천유역을 선정하였다. 대전 3대 하천 유역의 물수지와 도시화에 따른 영향을 파악하기 위하여 SWAT을 이용한 물순환 분석시스템을 구축하였다. 모형적용 결과, 유출량과 지하수 수위 변화 등 대전 3대 하천 유역의 특성을 관측치에 가깝게 모의할 수 있었다. 모델의 검보정 실시결과에서 나타난 모델의 계산 값들의 관측된 유출량뿐 아니라 기저유출량 및 지하수 수위와의 높은 상관관계는 본 연구에서 구축한 모델의 구조나 변수의 유효성에 많은 신뢰도를 제공한다고 판단된다. SWAT을 이용하여 대전 3대 하천 유역의 물수지 분석 및 도시화에 따른 영향을 평가하였다. 물수지 분석결과에 의하면, 전체적으로 총 유출량 중 지하수 유출량이 47%정도, 중간 유출량이 31% 그리고 지표유출량이 22%이다. 각 소유역의별 유출 성분 분석결과는 각 소유역의 토지 이용도, 토양 그리고 지형적 특징에 따른 유출 특성을 확인하였다. 도시화 영향 분석 결과 전체적으로 1975년에서 2000년까지 갑천 유역의 약 5%가량의 도시화는 총 유출량의 변화에 있어서는 현저한 차이를 보이지 않았으나, 각 유출 성분의 경우에는 많은 영향이 있는 것으로 나타났다. 특히 지표유출량은 45% 가량의 증가를 보였고, 전체 유역의 지하수함양 량이 5%정도 감소한 반면, 도시화가 31%정도 진행된 소유역의 경우에는 17%정도의 현저한 감소를 나타냈다. 본 연구에서 수행한 물수지 분석 및 도시화 영향분석 결과는 향후 대천 3대 하천의 생태하천복원을 위한 물순환 정상화 대책마련 및 하천의 유량확보방안 마련에 기초자료를 제공할 수 있을 것이다.득증대를 꾀함으로 농촌문제 해결에 도움이 될 것으로 기대된다. 본 연구를 통해 GIS 와 RS의 기술이 농촌분야에 더 효율적으로 적용될 것으로 기대되며, 농업기술센터를 통한 정보제공을 함으로써 대농민 서비스 및 농업기관의 위상이 제고 될 것으로 기대된다.여 전자파의 공간적인 가시화를 수행할 수 있었다. 본 전자파 시뮬레이션 기법이 실무에 이용될 경우, 일반인이 전자파의 분포에 대한 전문지식을 습득할 필요 없이, 검색하고자 하는 지역과 송전선, 전철 등 각종 전자파의 발생 공간 객체를 선택하여 실생활과 관련된 전자파 정보에 예측할 수 있어, 대민 환경정보 서비스 질의 개선측면에서 획기적인 계기를 마련할 것으로 사료된다.acid$(C_{18:3})$가 대부분을 차지하였다. 야생 돌복숭아 과육 중의 지방산 조성은 포화지방산이 16.74%, 단불포화지방산 17.51% 및 다불포화지방산이 65.73%의 함유 비율을 보였는데, 이 중 다불포화지방산인 n-6계 linoleic acid$(C_{18:2})$와 n-3계 linolenic acid$(C_{18:3})$가 지질 구성 총 지방산의 대부분을 차지하는 함유 비율을 나타내었다.했다. 하강하는 약 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 전

• Journal of the Korean GEO-environmental Society
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• v.18 no.12
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• pp.47-57
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• 2017

In this study, a predictive analysis was conducted on sediment disaster hazard area by selecting six research areas (Chuncheon, Seongnam, Sejong, Daejeon, Miryang and Busan) among the urban sediment disaster preliminary focus management area. The models that were used in the analysis were the existing models (SINMAP and TRIGRS) that are commonly used in predicting sediment disasters as well as the program developed through this study (LSMAP). A comparative analysis was carried out on the results as a means to review the applicability of the developed model. The parameters used in the predictions of sediment disaster hazard area were largely classified into topographic, soil, forest physiognomy and rainfall characteristics. A predictive analysis was carried out using each of the models, and it was found that the analysis using SINMAP, compared to LSMAP and TRIGRS, resulted in a prediction of a wider hazard zone. These results are considered to be due to the difference in analysis parameters applied to each model. In addition, a comparison between LSMAP, where the forest physiognomy characteristics were taken into account, and TRIGRS showed that similar tendencies were observed within a range of -0.04~2.72% for the predicted hazard area. This suggests that the forest physiognomy characteristics of mountain areas have diverse impacts on the stability of slopes, and serve as an important parameter in predicting sediment disaster hazard area.

• Journal of the Korea Institute of Building Construction
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• v.16 no.6
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• pp.519-527
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• 2016

The demand of construction risk analysis is rapidly increased to improve the competitiveness of construction companies and the sound management of the construction project. However, estimating the amount and uncertainty of the risk is difficult due to the wide range of risks in the construction industry. Moreover, most of the research on risk management of construction risk is only focused on the causes of risk without separate the internal and external risk. This study statistically analysis the internal risk and external risk based on the accidents cases which are caused at construction sites to define the difference and importances of the risk. An accident cause analysis and T-test analysis are carried out to reach the goal of study. The results of the study are expected to be used as a guideline of construction project risk analysis.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.15 no.1
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• pp.1-33
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• 2020

연구 목적 : 본 연구는 근골격계 질환에 대한 수기치료가 갖는 경제적 효과를 체계적으로 평가해 보기 위해 시행되었다. 연구 방법 : 2017년 2월 2일까지 국내외 관련 문헌을 체계적으로 검색 하였으며, 연관된 체계적 고찰 논문의 참고문헌을 조사하였다. 두 명의 연구자가 독립적으로 문헌을 선택하고, 비뚤림 위험 평가 및 경제성 평가 질 평가, 자료 추출을 시행하였다. 연구 결과 : 총 3,327개의 논문을 검토하여 최종적으로 18개의 무작위 대조 연구가 포함되었다. 경제성 평가는 수기요법과 다른 치료방법간의 유효성 비교를 통해 시행되었다. 요부 통증, 견관절 통증 및 외측 상과염 치료에 있어 침치료, 견인치료, 주사치료, 일반의 치료, 척추 안정화 기법 및 통증관리 치료보다 비용 효과적인 것으로 나타났다. 또한 또한, 수기치료는 경항통, 흉통, 고관절염 혹은 슬관절염, 경추신경병증 및 수부손상 치료에 있어 일반적 치료, 물리치료, 자가 치료 프로그램, 견인 치료에 비하여 효과적인 치료인 것으로 확인되었다. 결론 : 18개의 논문 중 10개의 논문에서 근골격계 질환 치료에 있어 수기치료가 경제적으로 효과가 있는 것으로 나타났다. 이러한 결과는 다른 치료방법에 비해 수기요법이 근골격계 질환에 있어서 경제적 가치가 있음을 시사하는 내용이다. 하지만, 근골격계 질환 수기치료의 경제성 평가에 대한 선행 연구는 전반적으로 부족한 실정으로, 보다 정확한 결과를 제시하고 정책결정을 위한 효과적인 제안을 위해서는 체계적인 추가 연구가 필요하다 사료되는 바이다.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.9
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• pp.201-208
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• 2013

In this paper, we studied on improvement for radiated EMI of USB power line of cable. it is made by using wireless video access point system for confirming the phenomenon of radiated EMI from cable. then, we make sure that the limit exceed through the initial measurement of radiated EMI limit criteria in comparison to about 3 [dBuV/m]~15 [dBuV/m]. after that we confirmed the resonance in power line of cable through measurement of s-parameters. so, we confirmed the relation radiated EMI and power line of cable resonance and we reduced radiated EMI in power line of cable through a capacitor and low pass-band filter using the technique of power networks management. in conclusion, we suggested how to reduce power line of cable resonance applied for the improved method. and we confirmed that suggested reduction method is suitable through testing radiated EMI. the result of radiated EMI reduction limit criteria 40[dBuV/m]~47[dBuV/m] in comparison to about 3 [dBuV/m]~20 [dBuV/m].