Radiation Damage to Ni-based Alloys in Wolsong CANDU Reactor Environments

권준현,진형하,이경근,박동환 한국원자력학회 2019 Nuclear Engineering and Technology Vol.51 No.3

Radiation damage due to neutrons has been calculated in Ni-based alloys in Wolsong CANDU reactorenvironments. Two damage parameters are considered: displacement damage, and transmutation gasproduction. We used the SPECTER and SRIM computer codes in quantifying radiation damage. In addition,damage caused by Ni two-step reactions was considered. Estimations were made for the annulusspacers in a CANDU reactor that are located axially along a fuel channel and made of Inconel X-750. Thecalculation results indicate that the transmutation gas production from the Ni two-step reactions ispredominant as the effective full power year increases. The displacement damage due to recoil atomsproduced from Ni two-step reactions accounts for over 30% out of the total displacement damage.

케빈 린치의 도시 이미지 요소가 보행만족도에 미치는영향 분석

권준현,조서연,이수기 한국도시설계학회 2022 도시설계 : 한국도시설계학회지 Vol.23 No.6

Walking activity has a positive effect on human activity and urban vibrancy andis an important factor for the organization of an eco-friendly city. This study usedwalking satisfaction data as an evaluation measure of walking activity and analyzedthe effects on walking satisfaction by quantifying various elements existing in thewalking environment into five city image elements defined by Kevin Lynch. Cityimage elements were quantified based on the walking radius, which is themicroscopic spatial level of city, and a multilevel ordered logistic regression modelwas used to analyze the effect on walking satisfaction. As a result, it was foundthat the average road width and road length as a path element, the presence orabsence of railroads as an edge element, the ratio of land use mix and commercialfacilities as a district element, the average order of intersections and the highestnodule importance as a node element, and the number of urban planning facilitiesas a landmark element had statistically significant relation with walking satisfaction. As such, this study empirically analyzed the relationship between the Kevin Lynch’sthe city image elements and walking satisfaction and suggested some implications toimprove walking satisfaction. 보행활동은 인간의 신체활동과 도시활력에 긍정적인 영향을 주며, 친환경적인 도시의 조성에중요한 요인이다. 본 연구는 보행활동의 평가 척도로 보행만족도 자료를 활용하였으며, 보행환경에 존재하는 다양한 요소를 케빈 린치가 정의한 다섯 가지 도시 이미지 요소로 정량화하여보행만족도에 미치는 영향을 분석하였다. 도시 이미지 요소는 도시 공간의 미시적 수준인 보행반경을 기준으로 정량화하였으며, 보행만족도에 미치는 영향 분석을 위해 다수준 순서형 로지스틱 회귀모형을 사용하였다. 분석 결과, 통로에 해당하는 평균 도로 폭과 도로 평균 길이, 경계에해당하는 철로 유무, 구역에 해당하는 토지이용혼합도와 상업시설의 비율, 결절점에 해당하는교차로 평균 차수와 최고 결절점 중요도, 랜드마크에 해당하는 도시계획시설의 수가 보행만족도와 통계적으로 유의한 상관관계를 가지는 것으로 나타났다. 본 연구는 보행환경 요소를 케빈 린치의 도시 이미지 요소로 정량화하여 보행만족도와의 관계를 실증적으로 분석하고 정책적 시사점을 제시하였다.

분위수 부스팅을 이용한 미세먼지 농도 예측

권준현,임예지,오희석,Kwon, Jun-Hyeon,Lim, Yaeji,Oh, Hee-Seok 한국통계학회 2015 응용통계연구 Vol.28 No.1

고농도 미세먼지($PM_{10}$)에 노출되는 것은 호흡기 질환 뿐만 아니라 피부, 안구, 심혈관계 질환 등을 야기한다. 따라서 미세먼지 농도를 정확히 예측하는 방법을 개발하는 것은 국민건강과도 깊은 관련이 있다. 현재 국립환경과학원에서는 미세먼지 농도가 높은 "나쁜날씨"를 예측하기 위해 의사결정나무 모형을 사용하고 있다. 그러나 모형 자체의 불안정성은 차치하더라도 의사결정나무는 전체 데이터의 9%밖에 차지하지 않는 "나쁜날씨"를 예측하기에 적합하지 못하다. 본 논문에서는 국립환경과학원에서 사용하는 모형의 부정확성과 부적절성을 제시하는 한편, 분위수 손실 함수를 적용한 새로운 모형의 유용성을 제시한다. 그리고 새로운 모형의 성능을 여러 ${\tau}$ 값에 대해 평가하고 비교를 통해 기존 모형 교체의 타당성을 보인다. Concerning the national health, it is important to develop an accurate prediction method of atmospheric particulate matter (PM) because being exposed to such fine dust can trigger not only respiratory diseases as well as dermatoses, ophthalmopathies and cardiovascular diseases. The National Institute of Environmental Research (NIER) employs a decision tree to predict bad weather days with a high PM concentration. However, the decision tree method (even with the inherent unstableness) cannot be a suitable model to predict bad weather days which represent only 4% of the entire data. In this paper, while presenting the inaccuracy and inappropriateness of the method used by the NIER, we present the utility of a new prediction model which adopts boosting with quantile loss functions. We evaluate the performance of the new method over various ${\tau}$-value's and justify the proposed method through comparison.

주거환경에 대한 거주민의 만족도와 영향요인 분석 - 직방 아파트 리뷰 빅데이터와 딥러닝 기반 BERT 모형을 활용하여 -

권준현,이수기 한국지역학회 2023 지역연구 Vol.39 No.2

Satisfaction on the residential environment is a major factor influencing the choice of residence and migration, and is directly related to the quality of life in the city. As online services of real estate increases, people’s evaluation on the residential environment can be easily checked and it is possible to analyze their satisfaction and its determining factors based on their evaluation. This means that a larger amount of evaluation can be used more efficiently than previously used methods such as surveys. This study analyzed the residential environment reviews of about 30,000 apartment residents collected from ‘Zigbang’, an online real estate service in Seoul. The apartment review of Zigbang consists of an evaluation grade on a 5-point scale and the evaluation content directly described by the dweller. At first, this study labeled apartment reviews as positive and negative based on the scores of recommended reviews that include comprehensive evaluation about apartment. Next, to classify them automatically, developed a model by using Bidirectional Encoder Representations from Transformers(BERT), a deep learning-based natural language processing model. After that, by using SHapley Additive exPlanation(SHAP), extract word tokens that play an important role in the classification of reviews, to derive determining factors of the evaluation of the residential environment. Furthermore, by analyzing related keywords using Word2Vec, priority considerations for improving satisfaction on the residential environment were suggested. This study is meaningful that suggested a model that automatically classifies satisfaction on the residential environment into positive and negative by using apartment review big data and deep learning, which are qualitative evaluation data of residents, so that it’s determining factors were derived. The result of analysis can be used as elementary data for improving the satisfaction on the residential environment, and can be used in the future evaluation of the residential environment near the apartment complex, and the design and evaluation of new complexes and infrastructure. 주거환경에 대한 만족도는 주거지 선택 및 이주 등에 영향을 미치는 주요인으로, 도시에서의 삶의 질과 직접적으로 연결된다. 최근 온라인 부동산 서비스의 증가로 주거환경에 대한 사람들의 만족도를 쉽게 확인할수 있으며, 사람들이 평가하는 내용을 바탕으로 주거환경 만족 요인에 대한 분석이 가능하다. 이는 기존에 활용되던 설문조사 등의 방식보다 더 많은 양의 평가를 효율적으로 활용할 수 있음을 의미한다. 본 연구는 서울특별시를대상으로 온라인 부동산 서비스인 ‘직방’에서 수집된 약 3만여 건의 아파트 리뷰를 분석에 활용하였다. 리뷰에 포함된 추천 평점을 토대로, 아파트 리뷰를 긍정적, 부정적으로 분류하고, 딥 러닝 기반 자연어 처리 모델인 BERT (Bidirectional Encoder Representations from Transformers)를 사용하여 리뷰를 자동으로 분류하는 모델을 개발하였다. 이후 SHAP(SHAPley Additive exPlanation)를 이용하여 분류에 중요한 역할을 하는 단어 토큰을 도출함으로 주거환경 만족도의 영향요인을 도출하였다. 더 나아가 Word2Vec을 이용하여 관련 키워드를 분석함으로써주거환경에 대한 만족도 개선을 위한 우선 고려사항을 제시하였다. 본 연구는 거주자의 정성평가 자료인 아파트 리뷰 빅데이터와 딥러닝을 활용하여 주거환경에 대한 만족도를 긍정적, 부정적으로 자동 분류하는 모형을 제안하여그 영향요인을 도출하는데 의의가 있다. 분석결과는 주거환경 만족도 향상을 위한 기초자료로 활용될 수 있으며 향후 아파트 단지 인근 주거환경 평가, 신규 단지 및 기반시설의 설계 및 평가 등에 활용될 수 있다.

2017년 자살 관련 지표들과 추이

권준현,양지은,주영준,박은철,장성인 한국보건행정학회 2019 보건행정학회지 Vol.29 No.1

Suicide is a major public health issue that causes over 800,000 deaths each year globally. Korea ranks high in suicide rates, in which around 24.3 per 100,000 individuals are reported to have died by intentional self-harm in 2017 according to Statistics Korea. The aim of this study was to examine the current status and trend of suicide ideation and attempt using data from the following five sources: Korean National Health and Nutrition Examination (KNHANES, ‘07–13, ‘15–17), Korean Community Health Survey (KCHS, ‘08–09, ’13, ’17), Korean Wealth Panel Study (KOWEPS, ‘12–17), Korea Health Panel Survey (KHP, ‘10–13), and Statistics Korea (1983–2017). Suicide ideation and attempts were also further examined based on equalized household income levels. Data published by Statistics Korea were used to show the updated suicide rate and number of deaths by intentional self-harm. The rate of suicide ideation at the recent year was 4.73% (KNHANES, ‘17), 6.96% (KCHS, ‘17), 1.63% (KOWEPS, ‘17), and 5.39% (KHP, ‘13). That of suicide attempts as recent year was 0.71% (KNHANES, ‘17), 0.32% (KCHS, ‘17), and 0.09% (KOWEPS, ‘17). Annual percentage change of suicidal ideation was -15.4% (KNHANES, ‘07–17), -2.5% (KCHS, ‘08–17), -8.6% (KOWEPS, ‘12–17), and -10.9% (KHP, ‘10–13). Annual percentage change of suicide attempts was -4.0% (KNHANES, ‘07–17), -4.4% (KCHS, ‘08–17), and -14.9% (KOWEPS, ‘12–17). Individuals with lower income levels were more likely to experience suicide ideation and attempts. Considering that Korea still shows a high suicide rate despite the continuously decreasing trend of suicide ideation and attempt, continuous observation and appropriate policy implementation regarding suicide related problems are necessary.

노냉각재 내의 방사성물질추정 연구

권준현,강창순 서울대학교 공과대학 1991 공대연구보고 Vol.23 No.1

A Rare Complication after Latissimus Dorsi Flap Breast Reconstruction: Radial Nerve Palsy

권준현,김재봉,이정우,최강영,정호윤,조병채,양정덕 대한미용성형외과학회 2016 Archives of Aesthetic Plastic Surgery Vol.22 No.3

Among autologous breast reconstruction techniques, breast reconstruction using the latissimus dorsi musculocutaneous flap is widely used, offering advantages including the relative simplicity of the procedure and the reliable and consistent vascularity of the flap. Accordingly, more than 500 cases have been performed in the past 8 years at Kyungpook National University Medical Center. This study reports on a rare case involving a radial nerve neuropathy complication which was experienced for the first time at the medical center. The current case demonstrates that in addition to common complications, such as seroma of the donor site and scarring, additional intraoperative complications in areas unrelated to the surgical site can occur, including radial nerve neuropathy in the opposite arm.

웨이트 트레이닝과 플라이오메트릭 트레이닝이 대학축구선수의 무산소성 운동능력에 미치는 영향

권준현,변주원,이용수 한국체육과학회 2022 한국체육과학회지 Vol.31 No.3

The purpose of this study was to investigate the effects of weight training and plyometric training on anaerobic ability including speed, power, and agility of university football players. For the study, 17 players had been assigned to WG(n=9) and PG(n=8) after pre-test. The participants participated in 6-week training program of 2-3 times in a week. The data obtained from pre-test and post-test were further analyzed using 2 way-repeated measures ANOVA and paired t-tset. According to speed test result, we found that there is no significant difference between WG and PG. However, WG showed significant improvement in post-test compared to pre-test unlike PG. Also, we found that there is no significant difference between WG and PG in power test result. Nevertheless, WG and PG both showed significant improvement in post-test compared to pre-test. Finally, there is no significant difference between WG and PG in agility test. However, WG and PG both showed significant improvement in post-test compared to pre-test. The results of this study showed that weight training affected improvement of speed, power, and agility of university football players. On the other hand, plyometric training affected improvement of power and agility of university football players. Therefore, weight training and plyometric training are considered as essential training for the modern football players who should perform higher percentage of high intensity movement compared to the past.

평판형 3차원 스캐닝 장치 개발

권준현(JunHyeon Kwon),김욱휘(UkHwi Kim),박동진(DongJin Park),이재운(JaeWoon Lee),이민재(MinJae Lee),박순용(SoonYong Park) 한국정보과학회 2017 한국정보과학회 학술발표논문집 Vol.2017 No.12

한중 50대와 20대의 소비가치 비교연구를 통한 제품 및 서비스 콘텐츠 개발 방향 탐색

권준현(Junhyun Kwon),한세미(Semi Han),김숙응(Sook-Eung Kim),김은혜(Eunhye Kim) 한국콘텐츠학회 2018 한국콘텐츠학회논문지 Vol.18 No.12

전세계적인 고령화 현상 및 베이비붐세대의 고령층 진입에 따라 시니어 대상 비즈니스에 대한 관심과 기대가 증가하고 있다. 그럼에도 불구하고 수요층에 대한 이해 부족 및 한정적인 내수시장 규모 등 때문에 국내 관련 산업의 성장이 더디게 이루어지고 있다. 이의 활성화를 위해서는 국내 및 해외 시니어에 대한 이해 제고와 이를 기반으로 한 제품 및 서비스 콘텐츠 전략 제시가 필요하다. 이에 따라 본 연구는 소비가치 개념을 적용하여 연령대(20대 vs. 50대) 및 국가간(한국 vs. 중국) 행동을 탐색함으로써, 각 집단이 중요하게 인식하는 소비가치를 베이비붐세대이자 예비시니어층인 50대 소비자를 중점으로 비교분석하고 이들을 위한 제품 및 서비스 콘텐츠 개발 방향을 제안하였다. 연령 및 국가간 소비가치 비교분석을 위하여 설문을 진행하였으며, 설문문항은 12개 소비가치의 하위차원인 총 40개의 문항으로 구성되었다. 분석결과를 통해 예비시니어층인 50대에 대한 이해 제고가 가능하며 이는 타겟에 적절한 콘텐츠 기획, 개발, 유통, 홍보등의 전략 구축에 활용될 수 있다. Senior business has been paid attention due to rapid global aging and baby boomers turning 60. However, senior business is not successful as expected because of a lack of understanding of consumers and small size of Korean domestic market. Understanding of senior consumers and overseas markets and providing attractive product and service contents needs to overcome the current challenges. Therefore, this study explores and compares consumers of different generation and different countries. We employ consumption value theory and analyze which consumption values are perceived strongly by each four group(Korean consumers in their 20s, Korean their consumers in 50s, Chinese consumers in their 20s, and Chinese consumers in their 50s). We conducted online survey to compare consumption values among samples of consumers in two countries: Korea and China. There are forty survey instruments in twelve consumption values. The results can be used to develop a strategy for planning, developing, distributing, and promoting product and service contents which consumers, in particular baby boomers, have a strong intention to purchase it.