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Study on The Warranty of Opposing Through Flow Gap Acceptance Time for more Efficient Management of Permissive Left-Turn (비보호 좌회전 효율성 제고를 위한 대향 직진 교통류의 Gap-Time기준 연구)

  • Baik, Seung-Yup;Park, Ki-Soo
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.10 no.4
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    • pp.107-115
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    • 2011
  • Since 2009 The Korean National Police Agency has been pushed "permissive left-turn" forward in order to making progress in Korean traffic operations system. Preceding researches manuals and guidelines present 6 standards(# of accidents # of lanes, pedestrian volume sight # of permissive left-turn lanes vehicle volume) as installation permissive left-turn. But in practical affairs it is most important that secure enough Gap-time between permissive left-turn vehicle and opposite through lane vehicle to make permissive left-turn vehicle move safer and more efficiently. This study suggests applying gap acceptance theory in microscopic model to permissive left-turn installation standards. Analysis methods of this study are field data survey statistical analysis and microscopic simulation analysis. This study collected field data by using AVI recording and measured permissive left-turn vehicle intersection passing time(T1) and against the opposite through lane vehicle Gap-time(T2). And statistical analysis performed about two values that measured before to predict the functionality between T1 and T2. These studies to overcome the limit of sample size carried out a microscopic simulation(VISSIM) plan and collect more samples to input statistical analysis.

Psychosocial Interventions for Children and Adolescents after a Disaster: A Systematic Literature Review (1991-2015) (재난 후 소아청소년의 정신사회적 개입: 체계적 문헌고찰(1991~2015))

  • Lee, Mi-Sun;Hwang, Jun-Won;Lee, Cheol-Soon;Kim, Ji-Youn;Lee, Ju-Hyun;Kim, Eunji;Chang, Hyoung Yoon;Bae, Seung-Min;Park, Jang-Ho;Bhang, Soo-Young
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.27 no.4
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    • pp.278-305
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    • 2016
  • Objective: The aim of this systematic literature review is to analyze the psychosocial interventions for children and adolescents after disasters. Methods: We conducted a review of the extant research literature from 1991 to 2015 via a comprehensive search of the MEDLINE, EMBASE, Cochrane CENTRAL, PubMed and PsyclNFO databases. The keywords employed in this research included: 'child', 'adolescent', 'youth', 'disaster', 'posttraumatic', 'psychosocial', 'therapy' and 'intervention'. The researchers followed the PRISMA guidelines. A total of 850 articles were screened for their eligibility and fifty-nine were found to meet the study criteria. The final data analysis was performed based on the disaster type, study design, type of intervention, sample size, age, school grade, number of sessions, setting of intervention delivery, providers, approach and parent involvement. Results: Countries worldwide have experienced various kinds of disasters, including earthquakes, hurricanes, vessel accidents, tornados, tsunamis, volcanic eruptions, war, fire, terrorism, and traffic accidents. The types of psychosocial intervention that were conducted after these disasters included: psychological first aid, psychological debriefing, psychoeducation, trauma focused cognitive behavior therapy, eye movement desensitization reprocessing, prolonged exposure therapy, group play therapy and arts therapy, project interventions, school-based interventions and web-based interventions. Conclusion: The findings of the systematic literature review suggest that an appropriate psychosocial intervention could be utilized as evidence-based mental health treatment for children and adolescents after disasters.

The Structure of Plant Community on Orimok, Yongsil and Donnaeko Area in Mt. Halla (한라산 어리목, 영실, 돈내코지역의 식물군집구조)

  • 이경재;류창희;최송현
    • Korean Journal of Environment and Ecology
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    • v.6 no.1
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    • pp.25-43
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    • 1992
  • A survey of Orimok, Yongsil and Donnaeko area forest in Mt. Halla. was conducted using 71 sample plots of 500$m^2$ size. In the analysis of -actual vegetation, Carpinus tschonoskii and C. laxiflora community covered 53.7%, Quercus grosseserrata - Q. serrata community 25.8%, Pinus densiflora community 8.3%, Abies koreana community 4.5% and these communities covered 92.2% of Mt. Halla forest. The degree of 8, 9 and 10 in human disturbance of vegetation covered 64.5, 28.6 and 6.9% respectively. The classification by TWINSPAN and DCA ordination were applied to the study area in order to classify them into several groups based on woody plants and environmental variables. By two techniques, the plant community were divided into several groups by the aspect and altitude. The dividing groups are C. tschonoskii community, C. tschonoskii - Q. serrata community, P. densiflora - C. tschonoskii community, P. densiflora - C. laxiflora community, C. laxiflora community, C. laxifrora - Daphniphyllum macropodum - Eurya japonica community, P. densiflora community. The successional trends of tree species by both techniques seem to be from P. densiflora. Sorbus alnifolia through Q. serrata. Maackia faurier to C. tsihonoskii in Orimok and Yongsil area and from P. densifiora to C. laxiflora in Donnaeko area. There was no difference between the stand scores of. DCA and environmental variables.

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Fabrication, Estimation and Trypsin Digestion Experiment of the Thermally Isolated Micro Teactor for Bio-chemical Reaction

  • Sim, Tae-Seok;Kim, Dae-Weon;Kim, Eun-Mi;Joo, Hwang-Soo;Lee, Kook-Nyung;Kim, Byung-Gee;Kim, Yong-Hyup;Kim, Yong-Kweon
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.5 no.3
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    • pp.149-158
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    • 2005
  • This paper describes design, fabrication, and application of the silicon based temperature controllable micro reactor. In order to achieve fast temperature variation and low energy consumption, reaction chamber of the micro reactor was thermally isolated by etching the highly conductive silicon around the reaction chamber. Compared with the model not having thermally isolated structure, the thermally isolated micro reactor showed enhanced thermal performances such as fast temperature variation and low energy consumption. The performance enhancements of the micro reactor due to etched holes were verified by thermal experiment and numerical analysis. Regarding to 42 percents reduction of the thermal mass achieved by the etched holes, approximately 4 times faster thermal variation and 5 times smaller energy consumption were acquired. The total size of the fabricated micro reactor was $37{\times}30{\times}1mm^{3}$. Microchannel and reaction chamber were formed on the silicon substrate. The openings of channel and chamber were covered by the glass substrate. The Pt electrodes for heater and sensor are fabricated on the backside of silicon substrate below the reaction chamber. The dimension of channel cross section was $200{\times}100{\mu}m^{2}$. The volume of reaction chamber was $4{\mu}l$. The temperature of the micro reactor was controlled and measured simultaneously with NI DAQ PCI-MIO-16E-l board and LabVIEW program. Finally, the fabricated micro reactor and the temperature control system were applied to the thermal denaturation and the trypsin digestion of protein. BSA(bovine serum albumin) was chosen for the test sample. It was successfully shown that BSA was successfully denatured at $75^{\circ}C$ for 1 min and digested by trypsin at $37^{\circ}C$ for 10 min.

A National Study Explaining the Public Library Use among Korean Adults: Examining the Influence of Individual Characteristics, Local Library Inputs, and Local Government Investments (한국 성인의 공공도서관 이용에 영향을 미치는 주요 요인 분석 - 개인, 도서관의 특성 및 자치단체의 도서관 투자를 중심으로 -)

  • Kwon, Nahyun;Song, Kyeong-Jin
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.25 no.4
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    • pp.291-312
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    • 2014
  • The purpose of this national study is to identify the factors affecting the public library use among the Korean adult population. The study constructed a model of three types of factors to explain the frequency of public library visits: an individual's socio-demographic characteristics, input and output measures of the local library, and the community size and library investment of the local government. The data were collected from both a national representative sample of 1,000 adults of 18 years old or above who participated in a web survey and the 2013 National Library Statistics of Korea. It was found that a more frequent public library visit occurred when a person who read more and lived closer to the library, which was newly established in a small to medium-sized scale, who lives in a city with a greater population and with more library staff members serving a fewer patrons. Implications for future public library constructions and for public services were suggested based on the study findings.

Regulations and Guidelines for Planning and Design of Multi-regional Clinical Trials (다지역 임상시험의 계획 및 설계에 대한 국제 제도적 동향 분석)

  • Song, Yun-Kyoung;Sohn, Minji;Jeon, Ah Young;Kim, Jae Hyun;Ji, Eunhee;Oh, Jung Mi;Kim, In-Wha
    • Korean Journal of Clinical Pharmacy
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    • v.28 no.2
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    • pp.146-153
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    • 2018
  • Objective: Multi-regional clinical trials have been widely used for accelerating global drug development by multinational pharmaceutical companies. In this study, we aimed to review and analyze the international trends in regulations and guidelines on multi-regional clinical trials by regulatory authorities and international organizations, such as International Conference on Harmonisation, for referring to policies, including development of domestic guidelines for multi-regional clinical trials. Methods: The policies, regulations, and guidelines published by the US Food and Drug Administration, European Medicines Agency, Pharmaceuticals and Medical Devices Agency (Japan), and China Food and Drug Administration were searched, and the International Conference on Harmonisation E17 draft guideline was reviewed. Results: The regulatory authorities in developed countries have developed and implemented regulations and guidelines on multi-regional clinical trials to promote simultaneous global drug development and evaluate the regional differences in drug safety and efficacy. International Conference on Harmonisation developed the draft guideline for planning/designing of multi-regional clinical trials in 2016, which recommends the general principles for strategy-related issues and design of multi-regional clinical trials, and for protocol-related issues, such as consideration of regional variability, subject selection, dose selection, endpoints, comparators, overall sample size, allocation to regions, collecting information on efficacy and safety, and statistical analysis. Conclusion: It is important to understand the international regulatory requirements for designing and planning of multi-regional clinical trials for global drug development. Moreover, it is necessary to prepare multi-regional clinical trial guidelines in accordance with the Korean regulation for clinical trials and drug administration.

What is the effect of initial implant position on the crestal bone level in flap and flapless technique during healing period?

  • Al-Juboori, Mohammed Jasim;Ab Rahman, Shaifulizan;Hassan, Akram;Ismail, Ikmal Hisham Bin;Tawfiq, Omar Farouq
    • Journal of Periodontal and Implant Science
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    • v.43 no.4
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    • pp.153-159
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    • 2013
  • Purpose: The level of the implant above the marginal bone and flap design have an effect on the bone resorption during the healing period. The aim of this study is to detect the relationship between the level of the implant at the implant placement and the bone level at the healing period in the mesial and distal side of implants placed with flapless (FL) and full-thickness flap (FT) methods. Methods: Twenty-two nonsubmerged implants were placed with the FL and FT technique. Periapical radiographs were taken of the patient at implant placement, and at 6 and 12 weeks. By using computer software, bone level measurements were taken from the shoulder of the healing cap to the first bone implant contact in the mesial and distal side of the implant surface. Results: At 6 weeks, the correlation between the crestal bone level at the implant placement and crestal bone level of the FT mesially was significant (Pearson correlation coefficient=0.675, P<0.023). At 12 weeks, in the FT mesially, the correlation was nonsignificant (Spearman correlation coefficient=0.297, P<0.346). At 6 weeks in the FT distally, the correlation was nonsignificant (Pearson correlation coefficient=0.512, P<0.107). At 12 weeks in the FT distally, the correlation was significant (Spearman correlation coefficient=0.730, P<0.011). At 6 weeks in the FL mesially, the correlation was nonsignificant (Spearman correlation coefficient=0.083, P<0.809). At 12 weeks in the FL mesially, the correlation was nonsignificant (Spearman correlation coefficient= 0.062, P<0.856). At 6 weeks in the FL distally, the correlation was nonsignificant (Spearman correlation coefficient=0.197, P<0.562). At 12 weeks in the FL distally, the correlation was significant (Pearson correlation coefficient=0.692, P<0.018). Conclusions: A larger sample size is recommended to verify the conclusions in this preliminary study. The bone level during the healing period in the FT was more positively correlated with the implant level at implant placement than in the FL.

Effect of Korean Red Ginseng on Sleep : A Randomized, Placebo-Controlled Trial (고려 홍삼이 수면의 질에 미치는 영향 : 무작위 위약-대조군 연구)

  • Lee, Sun-Ah;Kang, Seung-Gul;Lee, Heon-Jeong;Jung, Ki-Young;Kim, Leen
    • Sleep Medicine and Psychophysiology
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    • v.17 no.2
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    • pp.85-90
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    • 2010
  • Objectives: Ginseng has a long history of being used in insomnia treatment and there is some evidence from animal studies of its sleep-enhancing property. From this, it can be assumed that ginseng has sleep-promoting effect in humans. The purpose of this study was to investigate the effect of Korean red ginseng on change of sleep architecture in humans. Methods: A total of 20 healthy young males with regular sleep and wake habits and without any psychiatric nor cognitive problems were selected based on review of sleep questionnaires and sleep diaries they completed followed by an interview with a board-certified psychiatrist. The subjects were randomly assigned to red ginseng or placebo for 2 weeks of trial. The total daily dose of ginseng was 4,500 mg. The polysomnographic recordings were made at baseline and at 2 weeks after. The effects of red ginseng and placebo on sleep were assessed by comparing the changes in polysomnographic variables between the two groups. Results: A total of 15 subjects, 8 from red ginseng group and 7 from placebo group, were included to undergo polysomnographic procedures. The red ginseng group showed tendencies to increase stage 3 sleep (p=0.087) and to decrease stage 2 sleep (p=0.071) from the baseline compared with the placebo group. Conclusion: Korean red ginseng tends to increase deep sleep and decrease shallow sleep. Our result is in line, at least in part, with previous findings that Korean red ginseng increased total and NREM sleep in rats. Further studies with higher ginseng dosage, larger sample size and longer trial duration should be conducted to confirm the sleep stabilizing and balancing effects of Korean red ginseng.

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Factors of Successful Aging and the Effect on Life Satisfaction by the Recognition of Old Age (노후연령인식 여부에 따른 성공적 노화 구성요소 차이 및 삶의 만족도에 미치는 영향)

  • Kim, Mee Ryoung
    • Korean Journal of Social Welfare
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    • v.65 no.1
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    • pp.227-245
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    • 2013
  • This study used the third wave of individual data of KReIs(Korean Retirement and Income Study) because the third wave of data only had the necessary variables which fit into this study. The data was collected in 2010 using national random sampling. The target population was adults who are older than 65 and the sample size of this study was 4,080. The factors of successful aging were compared by the recognition of old age (group (1): people who recognize they are not older adults(n=620); group (2): people who recognize they are older adults(n=3,460)). For comparison of each variable by the recognition of old age, t-test, chi-square test and ANCOVA were used depending on the types of variables. To test the effect on the life satisfaction of the factors of successful aging, hierarchical regressions were used for each group. 1) Except for the number of leisure activities, older adults who recognized they were not old(group (1)) had a higher level of factors composing of successful aging than older adults who recognized they were old(group (2)). 2) For group (1), age did not affect their life satisfaction in a statistically significant level, but for group (2) age negatively affected their life satisfaction. 3) The results indicated that cognitive and physical functioning were more important than avoiding disease and disability. 4) For group (2), IADL affected life satisfaction positively in a statistically significant level, but for group (1), IADL did not affect life satisfaction. 5) For group(2), whether they had a job or not affected the life satisfaction differently.

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The Influence of 'Healthy Couple Relationship' Education on the Relationship Formation Competencies and Marriage Values of High School Students ('건강한 커플관계' 교육이 고등학생의 관계형성능력과 결혼 가치관에 미치는 영향)

  • Yu, In-Young;Park, Mi-Jeong
    • Journal of Korean Home Economics Education Association
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    • v.31 no.4
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    • pp.129-147
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    • 2019
  • This study aimed at exploring the influence of 'Healthy couple relationship' education on the relationship formation competencies and marriage values of high school students. To achieve the research objective, the 'Healthy couple relationship' lesson plan developed by the author was executed in two high schools for eight weeks from September 1 to November 3, 2018 from which the effects were analyzed. The results are as follows. First, the 'healthy couple relationship' education for high school students has been effective in improving their relationship performance, which is a part of the home economics curriculum. In S high school, the paired t-test of pre-/post-test comparison results showed statistically significant differences in the areas of 'communication', 'conflict resolution' and 'relationship formation performance'. For Sejong City campus-type joint curriculum group, where Wilcoxson signed-rank test was applied due to small sample size, showed that the overall scores as well as all the subsections of 'relationship formation performance' (i.e., 'communication', 'self-understanding', 'conflict resolution', and 'empathy') have improved, although not statistically significant. Second, the 'Healthy couple relationship' education for high school students had positive effects on the marriage values of high school students. In S high school, students' perception of marriage values rendered a statistically significant positive change, while in campus-type joint curriculum in Sejong City, no statistical significance was detected. In conclusion, the 'Healthy couple relationship' education can help high school students build positive values by cultivating their 'relationship formation competence', which is a part of the competencies listed in home economics curriculum, and also broaden their understanding of marriage, by acquiring knowledge and skills to build healthy couple relationships, and learning to implement the knowledge and skills in their own lives.