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Analysis on the Driving Safety and Investment Effect using Severity Model of Fatal Traffic Accidents (대형교통사고 심각도 모형에 의한 주행안전성 및 투자효과 분석)

  • Lim, Chang-Sik;Choi, Yang-Won
    • Journal of Korean Society of Transportation
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    • v.29 no.3
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    • pp.103-114
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    • 2011
  • In this study, we discuss a fatal accident severity model obtained from the analysis of 112 crash sites collected since 2000, and the resulting relationship between fatal accidents and roadway geometry design. From the 720 times computer simulations for improving driving safety, we then reached the following conclusions:. First, the result of cross and frequency-analyses on the car accident sites showed that 43.7% of the accidents occurred on the curved roads, 60.7% on the vertical curve section, 57.2% on the roadways with radius of curvature of 0 to 24m, 83.9% on the roads with superelevation of 0.1 to 2.0% and 49.1% on the one-way 2-lane roads; vehicle types involved are passenger vehicles (33.0%), trucks (20.5%) and buses (14.3%) in order of frequency. The results also show that the superelevation is the most influencing factor for the fatal accidents. Second, employing the Ordered Probit Model (OPM), we developed a severity model for fatal accidents being a function of on various road conditions so as to the damages can be predicted. The proposed model possibly assists the practitioners to predict dangerous roadway segments, and to take appropriate measures in advance. Third, computer simulation runs show that providing adequate superelevation on the segment where a fatal accident occurred could reduce similar fatal accidents by at least 85%. This result indicates that the regulations specified in the Rule for Road Structure and Facility Standard (description and guidelines) should be enhanced to include more specific requirement for providing the superelevation.

Analysis of Correlation between the Cause of Urbanization and Urbanization Effect of Busan by Using Daily Minimum Temperatures (일최저기온을 이용한 부산의 도시화효과와 도시화 원인과의 상관성 분석)

  • Park, Myung-Hee;Lee, Joon-Soo;Ahn, Ji-Suk;Suh, Young-Sang;Han, In-Seong;Kim, Hae-Dong
    • Journal of Environmental Science International
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    • v.21 no.12
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    • pp.1477-1485
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    • 2012
  • This study examined urbanization effects and the causes of urbanization, urban population growth, increase of the city scale, land cover change, and human cultures and economic activities, using the daily minimum temperatures of the past 50 years (1961-2010) with the subject of Busan and analyzed correlations between urbanization effects and the causes of urbanization. Thereby, this paper drew a conclusion as below: 1) Due to the urbanization effects, the average annual daily minimum temperature increased as about $1.2^{\circ}C$; however, except for the factor of urbanization, the increase was shown as about $0.2^{\circ}C$. The occupancy of urbanization effects in the total temperature increase was quite high as about 83%. 2) Just like other cities experiencing urbanization, Busan, too, sees population growth and the expansion of city area as well as increased urbanization effects. First of all, correlation between population growth and urbanization effect was high as 0.96 before 1985 while it was lowered as 0.19 after 1985. Also, correlation between the increase of city area and urbanization effect was high as 0.64 and 0.79 before and after 1985. 3) Regarding the correlation between long-term land use change and urbanization effect, urbanization effect was affected greatly by the increase of city area (0.97) and reduction of green area (0.92). 4) Concerning human activities possible to affect the climatic factors of a city, this paper found the following factors: road length, car increase, power use, and the consumer price index, etc. And regarding the correlation between the three factors and urbanization effect, the correlation was higher in the consumer price index (0.97), the number of registered cars (0.89), power use (0.75), and road length (0.58) in order.

The Metaanalysis of Trends and Contents of Child Nursing Intervention Research (아동의 간호중재 연구현황 및 간호중재 효과에 대한 메타 분석)

  • Kim Eun Ju;Cho Kyung Mi
    • Child Health Nursing Research
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    • v.6 no.2
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    • pp.119-131
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    • 2000
  • The purpose of this study was to identify the trends and contents of intervention towards children using meta analysis, to support the basis for using in the field and research method about nursing intervention. We used 27 materials which was reported from 1970 to August, 1999 : dissertation study and Korean Nurses' Academic society Journals, the Journal of Korean Academic society of Adult Nursing, The Korea Journal of Maternal and Child Health Nursing. The types of intervention we used came from 3 different researchers. Snyder showed cognitive, movement, social sensory intervention. McCloskey & Bulechek categorized as the following : self-care assistance, acute care management, life-style alteration, health promotion, life support intervention, Craft & Denehy classified psychosocial intervention and biophysiological intervention. Some findings are summarized as follow : Out of the 27 researches sensory intervention had the most in there thesis, recently cognitive intervention research has a tendency to increase. 18 researches has acute care management in there theses, and health promotion was found the least. Out of the 27 thesis 15 thesis was classified as biophysiological intervention and 12 had psychosocial. 27 thesis had 11 types of interventions which originally was categorized by Snyder, therefore sensory intervention thesis had the most. 11 types of intervention which originally was classified by McClosky & Bulechek, teaching and information had the most out of acute care management. Out of 27 thesis, 14 had dealt with newborns, especially newborns with sensory intervention. Therefore school age and above had cognitive intervention which was used for teaching and information. Infants, preschool, schoolage children received acute care management the most, health promotion intervention was used towards adolescences. Depending on the characteristics of dependent variables, it was analysed using meta however 17 thesis are possible except primary experimental research. Mean effect size comparison by Snyder classification, cognitive intervention was the largest mean(1.51), sensory intervention was larger(0.71) also, movement intervention was in the middle(0.56) as shown. Comparison done by McClosky & Bulechek, the intervention leading to life style alteration was the largest mean(1.97), teaching was used the most. Comparison by Craft & Denehy classification, psychosocial intervention was larger(1.15) than biophysiological intervention (0.67). The result of nursing intervention through age classification, the largest weighted mean effect size in the research was towards infants and neonates. The research which was focused on nursing intervention, has important meaning in nursing practice and knowledge development. When we know that children's nursing intervention is necessary and overcome our biased view, efficiency of children's nursing intervention are increased and professionalized. Therefore results will be important basic data to guide a development of child nursing intervention & classification.

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Deleterious Effects of Shift Work in the Realm of Cognitive and Behavioral Domains : A Critical Review (인지 및 행동영역에서 교대 근무의 유해적인 영향 : 비판적 고찰)

  • Lee, Suji L.;Park, Chang-hyun;Ha, Eunji;Park, Shinwon;Hong, Haejin;Park, Su Hyun;Ma, Jiyoung;Kang, Ilhyang;Kang, Hahn;Song, William Byunghoon;Kim, Jungyoon;Kim, Jieun E.
    • Korean Journal of Biological Psychiatry
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    • v.24 no.2
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    • pp.59-67
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    • 2017
  • Shift workers experience a disruption in the circadian sleep-wake rhythm, which brings upon adverse health effects such as fatigue, insomnia and decreased sleep quality. Moreover, shift work has deleterious effects on both work productivity and safety. In this review, we present a brief overview of the current literature on the consequences of shift work, especially focusing on attention-associated cognitive decline and related behavioral changes. We searched two electronic databases, PubMed and RISS, using key search terms related to cognitive domains, deleterious effects, and shift work. Twenty studies were eligible for the final review. The consequences of shift work can be classified into the following three categories extracted from the literature review : 1) work accidents ; 2) commuting accidents such as car accidents that occur on the way to and from work ; and 3) attendance management at work (i.e., absenteeism, tardiness, and unscheduled early departure). These cognitive and behavioral consequences of shift work were also found to be associated with sleep disorders in shift workers. Thus, improvements in the shift work system are necessary in order to enhance workers' health conditions, work productivity, and safety.

The Effect Analysis of NEV(Neighborhood Electric Vehicle) Driving - with VISSIM Simulation - (저속형 전기자동차 주행시 시스템 영향분석 - VISSIM 시뮬레이션을 이용하여 -)

  • Yoon, Tae-Kwan;Baik, Nam-Cheol;Jung, In-Taek
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.11 no.2
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    • pp.77-82
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    • 2012
  • To share the lanes with conventional vehicles, traffic operation strategy is needed for NEV (Neighborhood Electric Vehicle). Because NEV cannot accelerate sharply as fast as common car include gasoline, diesel and LPG cars, they may interrupt traffic conditions and make traffic delay. After green lights turn on, all vehicles run through the street including NEV, but NEV have a maximum speed which is 50km/h. It can be an obstacle for following vehicles and will make traffic delay of the intersection. In this reason, we need to organize traffic systems like queue jump with priority traffic signal. To analyze the necessity for NEV road operations, we simulate three scenarios in congested and non-congested conditions. First is that we examine the condition which is mixed NEV and cars on the road, the second one is that we set up lane only NEV can accepted in simulation and last one is making queue jump lane and providing priority signal for NEV. In conclusion, we can conclude that making lane only for NEV is effective to improve travel speed when rate of NEVs is over 20%. Also queue jump lane and priority signal cannot make good effect to intersection delay and average speed.

Development of Free Flow Speed Estimation Model by Artificial Neural Networks for Freeway Basic Sections (인공신경망을 이용한 고속도로 기본구간 자유속도 추정모형개발)

  • Kang, Jin-Gu;Chang, Myung-Soon;Kim, Jin-Tae;Kim, Eung-Cheol
    • Journal of Korean Society of Transportation
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    • v.22 no.3 s.74
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    • pp.109-125
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    • 2004
  • In recent decades, microscopic simulation models have become powerful tools to analyze traffic flow on highways and to assist the investigation of level of service. The existing microscopic simulation models simulate an individual vehicle's speed based on a constant free-flow speed dominantly specified by users and driver's behavior models reflecting vehicle interactions, such as car following and lane changing. They set a single free-flow speed for a single vehicle on a given link and neglect to consider the effects of highway design elements to it in their internal simulation. Due to this, the existing models are limitted to provide with identical simulation results on both curved and tangent sections of highways. This paper presents a model developed to estimate the change of free-flow speeds based on highway design elements. Nine neural network models were trained based on the field data collected from seven different freeway curve sections and three different locations at each section to capture the percent changes of free-flow speeds: 100 m upstream of the point of curve (PC) and the middle of the curve. The model employing seven highway design elements as its input variables was selected as the best : radius of curve, length of curve, superelevation, the number of lanes, grade variations, and the approaching free-flow speed on 100 m upstream of PC. Tests showed that the free-flow speeds estimated by the proposed model were statistically identical to the ones from the field at 95% confidence level at each three different locations described above. The root mean square errors at the starting and the middle of curve section were 6.68 and 10.06, and the R-squares at these points were 0.77 and 0.65, respectively. It was concluded from the study that the proposed model would be one of the potential tools introducing the effects of highway design elements to free-flow speeds in simulation.

Correlation Between Public Library Service User Satisfaction and Loyalty and Moderator Variables (공공도서관 서비스이용자 만족도와 충성도의 상관관계분석 및 매개변수)

  • Lee, Seongsin
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.24 no.1
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    • pp.83-103
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    • 2013
  • According to the results from the recent research in Business field, the correlation between customer satisfaction and customer loyalty is not strong. Based on this understanding, the first purpose of this study was to investigate the correlation between public library service user satisfaction and public library service user loyalty. To achieve this purpose, the study conducted a survey of 240 public library users. The findings of this study are 1) the correlation between 'public library service user satisfaction' and 'public library service user loyalty' exists. However the strength of the correlation is moderate, 2) the correlation between 'public library service user satisfaction' and 'public library service users' intention to use new library services' is the weakest among the variables of 'public library service user loyalty', and 3) the correlation between 'public library service user satisfaction' and 'public library service users' intention to recommend library services to others is the strongest among the variables of 'public library service user loyalty'. The second purpose of this study was to find the moderator variables between public library service user satisfaction and public library service user loyalty. According to the study results, the following moderate variables are found: 1) physical accessibility, 2) lack of diversity in library service, 3) car-parking issues, 4) lack of diversity and recency in collections, and 5) lack of convenience in facilities.

The Study on Weldability of Boron Steel and Hot-Stamped Steel by Using Laser Heat Source (I) - Laser Weldability of Al-Si Coated Boron Steel Used for Hot Stamping Process - (레이저 열원을 이용한 보론강 및 핫스탬핑강의 용접특성에 관한 연구 (I) - 핫스탬핑 공정에 사용되는 Al-Si 코팅된 보론강의 레이저 용접특성 -)

  • Kim, Jong Do;Choi, So Young;Lee, Su Jin;Suh, Jeong
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.38 no.12
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    • pp.1367-1372
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    • 2014
  • As the awareness of the environmental crisis has recently increased around the world, numerous studies in the transport industry have been conducted to solve this problem through lightweight car bodies. The hot-stamping process has been presented as solution to achieve a light weight. Hot-stamping is a method that is used to obtain ultra-high strength steel (1,500 MPa or greater) by simultaneously forming and cooling boron steel in a press die after heating it to a temperature of $900^{\circ}C$ or above. This study involved a, fundamental examination of laser parameters to investigate the laser weldability of boron steel. As a result, the following optimum parameters for the shielding gas were found: Q = 20 l/min, ${\alpha}=40^{\circ}$, d = 20mm, and l = 0 mm. The hardness of butt weldment increasesed sharply as a result of martensite formation at the fusion zone.

Convergent Web-based Education Program to Prevent Dementia (웹기반의 치매 예방용 융합교육 프로그램 개발)

  • Park, Kyung-Soon;Park, Jae-Seong;Ban, Keum-Ok;Kim, Kyoung-Oak
    • The Journal of the Korea Contents Association
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    • v.13 no.11
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    • pp.322-331
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    • 2013
  • The purpose of the present study was to develop a convergent education contents for dementia prevention, operating on the web network applying modern information technology(IT). At the preparation stage, local and worldwide literatures related to dementia were analyzed followed by surveying industry demands, based on which the program was designed and developed. In the following enhancement stage, the program was modified as much as possible by advices obtained from experts in various fields. Development results of the present program are summarized as follows. Firstly, 645 intellect development model to prevent dementia was established through peer review and verification of convergent education theories by expert groups. This model was named as "Garisani" meaning "cognition capable of judging objects" in the Korean language. Secondly, 'Find a way' and 'Connect a line' modules were developed in the numeric field as well as 'Identify a letter(I, II)' modules, in the language field for web-based left brain training program. Thirdly, 'Find my car' and 'Vision training' modules in the attention field and 'Object inference' and 'Compare pictures' modules in the cognition field were developed for web-based right brain training program. Fourth, 'Pentomino' and 'BQmaze'(Brain Quotient and maze) modules in the space perception field and 'Visual training' in the memory field were developed for web-based left and right brains training. Fifth, all results were integrated leading to a 52 week Garisani convergent education program for dementia prevention.

The Clinical Study on 120 Cases with Traffic Accident (교통사고 환자 120례에 대한 임상적 고찰)

  • Lee, Ji-Eun;Jung, Hyo-Keun;Ryu, Chung-Ryul;Cho, Myoung-Rae;Wi, Jun;Ryu, Mi-Seon;Kim, Ja-Young
    • Journal of Acupuncture Research
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    • v.25 no.6
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    • pp.135-143
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    • 2008
  • Objectives : The main purpose of this research is to make a survey of the effective way of the Oriental medical care and to enlarge the range of Oriental medical treatment about traffic accidental patients. Methods : In following research, we surveyed 120 patients of traffic accident who were hospitalized in Dong-Shin Oriental Medical Hospital from October, 1, 2007 to August, 20, 2008 according to medical chart. Results : 1. In distribution of gender and age, the rate of male was 35.8%, that of female was 64.2% and the majority of the patients were twenties and thirties. 2. In the traffic accident patterns, the most was car crash from behind(61.7%) and after traffic accident, 75 patients(62.5%) visited our hospital for oriental medical treatment in less than 5days. 3. 46 patients(38.3%) choose the oriental medical treatment for the primary care and after medical care, 36 patients(31.7%) visited our hospital due to dissatisfaction of current treatment and maintained pain. 4. Partial pain was the chief complaint and the most of painful parts was neck(76.7%), followed by low back(69.2%). 5. Though radiation test, the most was cervical spine sprain(76.7%), followed by straightening of lumbar spine(66.7%). 6. In the periods of admission, less than 7 days was the most(53.3%), followed by less than 14 days(35.9%). 7. The treatment was effective to 93 patient out of 106 who had been hospitalized for less than 14 days. Conclusions : This data suggested that the Oriental medical care could be more effective treatment about traffic accidental patients without surgical injury.

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