• Title/Summary/Keyword: Time-to-event

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Slope Failure Prediction through the Analysis of Surface Ground Deformation on Field Model Experiment (현장모형실험 기반 표층거동분석을 통한 사면붕괴 예측)

  • Park, Sung-Yong;Min, Yeon-Sik;Kang, Min-seo;Jung, Hee-Don;Sami, Ghazali-Flimban;Kim, Yong-Seong
    • Journal of the Korean Geosynthetics Society
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    • v.16 no.3
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    • pp.1-10
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    • 2017
  • Recently, one of the natural disasters, landslide is causing huge damage to people and properties. In order to minimize the damage caused by continuous landslide, a scientific management system is needed for technologies related to measurement and monitoring system. This study aims to establish a management system for landslide damage by prediction of slope failure. Ground behavior was predicted by surface ground deformation in case of slope failure, and the change in ground displacement was observed as slope surface. As a result, during the slope failure, the ground deformation has the collapse section, the after collapse precursor section, the acceleration section and the burst acceleration section. In all cases, increase in displacement with time was observed as a slope failure, and it is very important event of measurement and maintenance of risky slope. In the future, it can be used as basic data of slope management standard through continuous research. And it can contribute to reduction of landslide damage and activation of measurement industry.

Evaluation on applicability of on/off-line parameter calibration techniques in rainfall-runoff modeling (온·오프라인 매개변수 보정기법에 따른 강우-유출해석 적용성 평가)

  • Lee, Dae Eop;Kim, Yeon Su;Yu, Wan Sik;Lee, Gi Ha
    • Journal of Korea Water Resources Association
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    • v.50 no.4
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    • pp.241-252
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    • 2017
  • This study aims to evaluate applicability of both online and offline parameter calibration techniques on rainfall-runoff modeling using a conceptual lumped hydrologic model. To achieve the goal, the storage function model was selected and then two different automatic calibration techniques: SCE-UA (offline method) and particle filter (online method) were applied to calibrate the optimal parameter sets for 9 rainfall events in the Cheoncheon catchment, upper area of the Yongdam multi-purpose dam. In order to assess reproducibility of hydrographs from the parameter sets of both techniques, the observed discharge of each event was divided into low flow (below average flow) and high flow (over average flow). The results show that the particle filter method, updating the parameters in real-time, provides more stable reproducibility than the SCE-UA method regardless of low and high flow. The optimal parameters estimated by SCE-UA are very sensitive to the selected objective functions used in this study: RMSE and HMLE. In particular, the parameter sets from RMSE and HMLE demonstrate superior goodness-of-fit values for high flow and low flow periods, respectively.

Analysis of Vertical Structure of Atmosphere on the Middle Part of the Yellow Sea (서해 중부 해상 대기의 연직구조 분석)

  • Yun, Yong Hun;Im, Ju Yeon;Kim, Baek Jo;Kim, Tae Hui;Seo, Jang Won;Jo, Ha Man
    • Journal of the Korean earth science society
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    • v.21 no.1
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    • pp.22-22
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    • 2000
  • To search out the characteristics of the lower and the upper atmospheric vertical structure, we selected the island(Oeyoundori Ochun-myen Poryeng city Chung-Nam) as an observation site, which is thought to represent the characteristics of ocean well, and observed the vertical structure of the atmosphere by Radiosonde. By using the results of the observation, we analyzed the changes of relative humidity(RH), temperature and wind when the cyclone and the anticyclone passed and compared the results in case of each event. To compare the vertical structure of the ocean atmosphere with those of the continent, we analyzed the values observed with using Radiosonde at Osan site.Through this study, we found that relative humidity changed as the cyclone and the anticyclone passed. That is, when the cyclone came, RH increased first in the upper atmosphere than in the lower and when the high came, RH in the upper decreased sharply to 10%. And the variations of relative humidity in ocean are bigger than those in continent. In the future, we plan to find out the relation between the vapor water in ocean and continent seasonally and daily through the observation in ocean and continent at same time.

Analysis of Vertical Structure of Atmosphere on the Middle Part of the Yellow Sea (서해 중부 해상 대기의 연직구조 분척)

  • Youn, Yong-Hoon;Lim, Joo-Yun;Kim, Baek-Jo;Kim, Tae-Hee;Seo, Jang-Won;Cho, Ha-Man
    • Journal of the Korean earth science society
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    • v.21 no.1
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    • pp.23-39
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    • 2000
  • To search out the characteristics of the lower and the upper atmospheric vertical structure, we selected the island(Oeyoundori Ochun-myen Poryeng city Chung-Nam) as an observation site, which is thought to represent the characteristics of ocean well, and observed the vertical structure of the atmosphere by Radiosonde. By using the results of the observation, we analyzed the changes of relative humidity(RH), temperature and wind when the cyclone and the anticyclone passed and compared the results in case of each event. To compare the vertical structure of the ocean atmosphere with those of the continent we analyzed the values observed with using Radiosonde at Osan site. Through this study, we found that relative humidity changed as the cyclone and the anticyclone passed. That is, when the cyclone came, RH increased first in the upper atmosphere than in the lower and when the high came, RH in the upper decreased sharply to 10%. And the variations of relative humidity in ocean are bigger than those in continent. In the future, we plan to f d out the relation between the vapor water in ocean and continent seasonally and daily through the observation in ocean and continent at same time.

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Study 1 of The 100 Best Chinese Films for Storytelling Content Development of Korea and China's Collaborative Film Production -Focused on Films in 1930's- (한중합작 영화의 스토리텔링 콘텐츠개발을 위한 중국 100대 영화연구 1 -1930년대 작품을 중심으로-)

  • Han, Dal-Ho
    • The Journal of the Korea Contents Association
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    • v.14 no.11
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    • pp.111-124
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    • 2014
  • This dissertation is to seek new valuable possibility of the 100 best Chinese films on storytelling in Chinese films as considering about content development of Korea and China's Collaborative film production and extension, that being magnified as a new content for variety of Korean film production. The moment to the Korean wave is getting cold in Japan, Korean wave is attempt to receive attention in new field through China by various image field with Korean drama's appeal. However, film content fall short of our expectation than media content, even if supporting much various attempts with Korea and China's Collaborative film production content. Specially, there are not satisfied films for Korea and China both counties's audience, although Korea and China's Collaborative film production has been produced steadily. The writer studies on stories of Chinese essential 100 films for searching deeply this problem. Among them, in selected 'The 100 Best Chinese Films' by China in 2005, films in 1930's are selected as the first step to study, and this dissertation searches to communicate storytelling's meaning in Chinese films through that time image. This studies what is the point of selected story by China, and there are what kind of worries. This dissertation considers that focused on characters, event and background. Chinese film in 1930's represented life in times through process of play development that is connected with poverty, reality of society, death, tragedy and tragicomedy.

Postoperative Outcomes of Mitral Valve Repair for Mitral Restenosis after Percutaneous Balloon Mitral Valvotomy

  • Lee, Ji Seong;Chee, Hyun Keun;Kim, Jun Seok;Song, Myong Gun;Park, Jae Bum;Shin, Je Kyoun
    • Journal of Chest Surgery
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    • v.48 no.5
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    • pp.328-334
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    • 2015
  • Background: There have been a number of studies on mitral valve replacement and repeated percutaneous mitral balloon valvotomy for mitral valve restenosis after percutaneous mitral balloon valvotomy. However, studies on mitral valve repair for these patients are rare. In this study, we analyzed postoperative outcomes of mitral valve repair for mitral valve restenosis after percutaneous mitral balloon valvotomy. Methods: In this study, we assessed 15 patients (mean age, $47.7{\pm}9.7years$; 11 female and 4 male) who underwent mitral valve repair between August 2008 and March 2013 for symptomatic mitral valve restenosis after percutaneous mitral balloon valvotomy. The mean interval between the initial percutaneous mitral balloon valvotomy and the mitral valve repair was $13.5{\pm}7years$. The mean preoperative Wilkins score was $9.4{\pm}2.6$. Results: The mean mitral valve area obtained using planimetry increased from $1.16{\pm}0.16cm^2$ to $1.62{\pm}0.34cm^2$ (p=0.0001). The mean pressure half time obtained using Doppler ultrasound decreased from $202.4{\pm}58.6ms$ to $152{\pm}50.2ms$ (p=0.0001). The mean pressure gradient obtained using Doppler ultrasound decreased from $9.4{\pm}4.0mmHg$ to $5.8{\pm}1.5mmHg$ (p=0.0021). There were no early or late deaths. Thromboembolic events or infective endocarditis did not occur. Reoperations such as mitral valve repair or mitral valve replacement were not performed during the follow-up period ($39{\pm}16months$). The 5-year event-free survival was 56.16% (95% confidence interval, 47.467-64.866). Conclusion: On the basis of these results, we could not conclude that mitral valve repair could be an alternative for patients with mitral valve restenosis after percutaneous balloon mitral valvotomy. However, some patients presented with results similar to those of mitral valve replacement. Further studies including more patients with long-term follow-up are necessary to determine the possibility of this application of mitral valve repair.

The Effects of MERS(Middle East Respiratory Syndrome) Event on the Psychosocial Wellbeing of Healthcare Workers and the Public with the Mediating Effect of Resilience (메르스(Middle East Respiratory Syndrome)사태에 따른 병원종사자와 일반인의 스트레스 정도가 사회심리적 건강에 미치는 영향과 회복탄력성의 매개효과)

  • Kwon, Hyuk-Min;Kim, Tae-Hyung;Choi, Mal-Rye;Kim, Byoung-Jo;Kim, Hyoung-Wook;Song, Ok-Sun;Eun, Hun-Jeong
    • Korean Journal of Psychosomatic Medicine
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    • v.25 no.2
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    • pp.111-119
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    • 2017
  • Objectives : The purpose of this study is to investigate the effects of stress on psychosocial wellbeing at the time of an outbreak of Middle East respiratory syndrome(MERS) and to investigate the effect of resilience as a mediator on the relationship between stress and psychosocial wellbeing. Methods : Perceived Stress Scale, Psychosocial Wellbeing Index Short Form, and the Conner-Davidson Resilience Scale was implemented for 156 medical persons who worked at the hospital in which exposure to MERS cases had been confirmed and 127 ordinary people. We conducted a Pearson correlation coefficient and a hierarchical multiple regression to confirm the effect of stress on psychosocial wellbeing and the mediating effect of resilience between stress and psychosocial wellbeing. Results : The higher the perceived stress, the lower the psychosocial wellbeing in both healthcare workers and the public. The higher the perceived stress, the lower the resilience and the research results showed that there was a partially mediating effect of resilience in the relationship between stress and psychosocial wellbeing. Conclusions : This study demonstrated that the degree of individual resilience can indirectly give a positive effect on the psychosocial wellbeing when people under the stress by MERS shows adverse effects on psychosocial wellbeing. This suggests that clinical intervention and psychosocial approach aiming at strengthening resilience is important to maintain mental health during crisis development.

A Dynamic Analysis of the Women's Labor Market Transition: With a Focus on the Relationship between Productive and Reproductive Labor (여성의 생산노동과 재생산노동의 상호연관성이 취업에 미치는 영향에 관한 경험적 연구)

  • 이재열
    • Korea journal of population studies
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    • v.19 no.1
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    • pp.5-44
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    • 1996
  • Wornen's lahor market participation as well as the policy concern for wider utilization of married women, have continuously grown up. However, research efforts on the determinants of women's labor market participation, in the context of the relationship hetween life courses and active entry into lahor market, has been far behind the growing interest in this field. This study has conducted an event histoiry analysis of women's labor market transition utilizing personal occupational history data collected by the Korea Institute for Women's Development in 1991. The analysis is divided into tow parts: First part introduces logit regression to analyze the determinants of women's labor market participation and exit. The second part employs Cox regression to see the variation of transition rate between employment and non-employment. The result shows that there is a wide variation in women's labor market participation according to age, cohort, and family formation. Special note is needed for the significantly negative effect of marriage and child birth on labor market participation. The transition pattern of lower class women with less education fits well to the prediction of neo-classical economics; but the tendency of highly educated women's regression to non-employment reveals the strong influence of the unfavorable labor market structure, which can be better explained by the neo-structuralist perspective. There is a strong trade-off between productive and reproductive labor of women, which can only be corrected by strong policy implementation, such as extended child care facilities, abolition of discriminatory employment practices, and expansion of flexible part-time employment.

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Review of 24th Seoul IAPD Congress (제 24회 서울 세계소아치과학회 개관(槪觀))

  • Lee, Sangho
    • Journal of the korean academy of Pediatric Dentistry
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    • v.41 no.1
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    • pp.93-118
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    • 2014
  • The Korean Academy of Pediatric Dentistry hosted the $24^{th}$ IAPD Congress in Seoul, Korea on June 12-15, 2013. The main theme of the congress was the "New visions in Pediatric Dentistry" A total number of 1,855 participants, including exhibitors and press from 67 countries, participated in the 24th IAPD Congress. The scientific program consists of 85 invited lectures, 126 oral presentations, and 553 poster presentations. 46 companies and organizations have supported and participated in Seoul IAPD Congress. Overall the congress was a success in terms of high attendance rate from 67 countries over the world. Considering the fact that Korea is located in the far-east, the number of overseas delegates(943) are remarkable. Also it is desirable to have over 100 delegates from developing countries which eventually aim to collaborate worldwide. The scientific program covered a variety of topics and many of the delegates stayed in the session room until the last day of the congress. Although it could have been more beneficial to allot more time for each speaker to discuss further, the program fit the Congress theme "New Visions for Paediatric Dentistry". All social event tickets were sold out early and it attracted participants with interesting program enabling participants to interact and exchange ideas outside of the meeting.

One-key Keyboard: A Very Small QWERTY Keyboard Supporting Text Entry for Wearable Computing (원키 키보드: 웨어러블 컴퓨팅 환경에서 문자입력을 지원하는 초소형 QWERTY 키보드)

  • Lee, Woo-Hun;Sohn, Min-Jung
    • Journal of the HCI Society of Korea
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    • v.1 no.1
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    • pp.21-28
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    • 2006
  • Most of the commercialized wearable text input devices are wrist-worn keyboards that have adopted the minimization method of reducing keys. Generally, a drastic key reduction in order to achieve sufficient wearability increases KSPC(Keystrokes per Character), decreases text entry performance, and requires additional effort to learn a new typing method. We are faced with wearability-usability tradeoff problems in designing a good wearable keyboard. To address this problem, we introduced a new keyboard minimization method of reducing key pitch. From a series of empirical studies, we found the potential of a new method which has a keyboard with a 7mm key pitch, good wearability and social acceptance in terms of physical form factors, and allows users to type 15.0WPM in 3 session trials. However, participants point out that a lack of passive haptic feedback in keying action and visual feedback on users' input deteriorate the text entry performance. We have developed the One-key Keyboard that addresses this problem. The traditional desktop keyboard has one key per character, but the One-key Keyboard has only one key ($70mm{\times}35mm$) on which a 10*5 QWERTY key array is printed. The One-key Keyboard detects the position of the fingertip at the time of the keying event and figures out the character entered. We conducted a text entry performance test comprised of 5 sessions. The participants typed 18.9WPM with a 6.7% error rate over all sessions and achieved up to 24.5WPM. From the experiment's results, the One-key Keyboard was evaluated as a potential text input device for wearable computing, balancing wearability, social acceptance, input speed, and learnability.

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