• KSCE Journal of Civil and Environmental Engineering Research
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• v.40 no.1
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• pp.87-95
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• 2020

With the advent of the 4^th industrial revolution and the combination of IoT, there have been diverse domestic and foreign researches for the development of construction industry. Especially, in the large-scale earthwork site where many and various construction equipments are put into, the control system between construction equipments is important for the increase of productivity. Thus, after developing the fleet management system for the optimum operation of construction equipments, the problems were checked and improved for each step in the process of application at site. In order to verify the site application process of the fleet management system for the optimum operation of construction equipments, the analysis on the productivity was performed by inputting the data used for the actual site and the site data using this system and then comparing the data through simulation. The analysis was limited to excavator and dump. In the results of the analysis, the rate of work per hour was increased to the range of 4 % while the cost price was decreased to 4 %. Even though the results of the analysis could be different depending on the site applied, the results showing the increase of workload of equipments and the decrease of cost price in the complex project at earthwork site verify the increase of productivity.

• Restorative Dentistry and Endodontics
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• v.31 no.2
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• pp.86-95
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• 2006

The purpose of this clinical study is to assess whether calcium hydroxide as an intracanal medication affects post-treatment pain in teeth especially odontogenic pain which comes from inflammation of the pulp and periradicular tissues when compared with no intracanal medication. From 213 patients who has been treated 237 root canals due to significant pain (moderate-to-severe) we recorded their age, sex, treated tooth, degree of pain, pre-operative states of the tooth. We classified patients into 2 test group; Group 1 (not gain intracanal $Ca(OH)_2$), Group 2 (gain intracanal $Ca(OH)_2$). Through the survey from the patients, we let them write down the occurrence and degree of post-treatment pain in 4hours, 2days, 7days after treatment as none, mild, moderate or severe. The followings were evaluated ; the overall incidence of flare-ups, the overall incidence of post-treatment pain in each group at each time period , the incidence of post-treatment pain in each group at each time period as related to pre-operative states of the teeth These were compared statistically with Chi-square analysis (p < 0.05). Under the condition of this investigation, no difference was observed in the incidence of post-treat-ment pain between the two groups. Therefore, $Ca(OH)_2$ as intracanal medication had no effect on preventing or decreasing the post-treatment pain.

• Journal of the Korea Convergence Society
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• v.9 no.4
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• pp.373-380
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• 2018

The purpose of this study was to identify the importance and performance ranking and differences in inflight meal service quality. Data were collected from A airlines passengers. In order to secure the validity and reliability of the measurement tools, exploratory factor analysis were conducted, accordingly meal, service, cleanliness were deduced. IPA results are as follows. First, the quadrant I consisted of meal flavor, meal quality, meal menu, balanced diet, korean food availability, cleanliness of dishes, cleanliness of crew clothes. In the II quadrant, appropriate temperature, appropriateness of meal distribute time, cleanliness of the meal were found. So, the airline managers should have the most interest in these attributes and had to improve first. The quadrant III showed meal quantity, liquor diversity, polite attitude, immediate response to the meal, knowledge of the meal, meal freshness. Lastly, the quadrant IV showed a variety of beverage and special meal order. It is considered that resource allocation is necessary for minimizing the amount of resources invested to the quadrant IV, and then it should be allocated the quadrant II, which is high in importance but low in performance.

• Journal of the korean academy of Pediatric Dentistry
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• v.44 no.1
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• pp.38-46
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• 2017

School nurses can play an important role in improving the prognosis of traumatized teeth of school children when they are informed about the immediate and proper dental first aid steps. The purpose of this study were to assess the awareness of school nurses concerning the management of traumatized teeth and to determine if a lecture on dental trauma management could improve school nurses'knowledge on this topic. School nurses in Gwangju and Jeonnam province completed a questionnaire before and after the lecture on the first-aid knowledge with particular focus on the following three categories. Questionnaires are composed of questions asking general information and about knowledge and proper attitude in case of the specific situation on dental trauma. According to previous studies, school nurses' knowledge tended to be higher compared with the teachers. Improvement of knowledge in school nurse was observed in emergency actions, in visiting time, replantation, carriage method, vaccine prescription related with luxation, and in possibility of fragment reattachment related with subluxation and fracture. In conclusion, it is recommended that periodical education are needed for improvement of school nurses'knowledge on proper management of dental trauma emergency.

• Journal of The Korean Association For Science Education
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• v.38 no.3
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• pp.379-392
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• 2018

This study aims to explore science inquiry teaching efficacy that middle school science teachers implementing science practice-based teaching for one year recognized as necessary for teaching science through science practice. Examining interview data in this study, science inquiry teaching efficacy was identified in both planning and implementing in the areas of managing efficacy, instructional strategy efficacy, and content knowledge efficacy. In planning science inquiry instruction, there is science curriculum management efficacy under managing efficacy. There are the efficacy of outlining science inquiry lesson, efficacy of organizing science practice, efficacy of questioning for science practice, and efficacy of understanding student science practice under instructional strategy efficacy. Under the content knowledge efficacy are contents and science practice understanding efficacy and core ideas efficacy. In implementing science inquiry instruction, managing efficacy includes science practice time management efficacy and science practice classroom culture efficacy. Instructional strategy efficacy includes efficacy of motivating student science practice, efficacy of responding to student science practice, efficacy of stimulating student active thinking, efficacy of student active engagement in argumentation, efficacy of evaluating student participation. No content knowledge efficacy have been identified in implementing science inquiry instruction.

• Journal of Korean Society of Transportation
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• v.25 no.6
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• pp.141-157
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• 2007

This paper evaluates the effects of privatization and deregulation on the firm-specific efficiency and total factor productivity (TFP) growth in the Korean and Japanese railways. Using a stochastic frontier approach and a generalized translog functional form, the paper specifies the equation system consisting of a multiproduct variable cost function and input share equations which is estimated with Zellner's iterative seemingly unrelated regression and the corrected least squares method. The Korean and Japanese railway firms are assumed to produce three outputs (Shinkansen passenger-kilometers, incumbent railway passenger-kilometers, ton-kilometers of freight) using three input factors (labor, fuel, maintenance and rolling stock). A monetary value of the ways and fixed installations held by the railroad firm is also included as a quasi-fixed input. The empirical results indicate that the average estimate of cost inefficiency is 2.57% for the total sample and on the average, JNR and JR Kyushu are found to be worst efficient while the most efficient railway firm in the sample is JR West. Also the cost efficiency levels of seven JRs have been improved after the reform and privatization of JNR. The findings also indicate that TFP growth of the privately-owned JRs are higher than those of the government-owned KNR and JNR. Three-island JRs and JR Freight have slightly higher TFP growth than Honshu JRs as well. Thus, the results suggest that managerial autonomy and increased competition via deregulation have improved efficiency and TFP growth.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.785-789
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• 2006

유역 수자원의 효율적인 관리 및 배분을 위해서는 세밀한 강우-유출관계의 규명이 무엇보다 중요하다. 이를 위해서는 먼저 하천 유출지점의 정확한 유량정보가 획득되어야 하며, 장기간에 걸쳐 신뢰성 있는 유량자료의 확보는 더욱 중요한 사항이다. 본 연구에서는 하천에서 관측된 유량자료를 장기간(1983년${\sim}$2004년)에 걸친 유출성분으로 분리하는 기법을 활용하여 제어지점의 유출량을 검증하였다. 유량자료를 출구지점의 관측유량$(Q_{ob})$을 회귀수$({\alpha}Q_e)$, 상류유입량$(Q_{up})$ 및 관측강우-유출량$({\beta}Q_{Rain})$의 성분으로 구분하여 산정하는 방식으로 유출량을 추정하였다. 여기서, 회귀수$({\alpha}Q_e)$란 유역 및 하도내 용수이용량의 회귀수, 상류유입량$(Q_{up})$은 상류 유출 제어지점의 관측유량으로 대청댐 방류량, 관측강우-유출량$({\beta}Q_{Rain})$은 유역내 강우에 의한 자연유출량이다. 여기서 사용된 수문기초자료는 대청댐 방류량, 대전 및 청주권 취수량, 강우에 의한 자연유출량, 공주관측유량 등으로 각 성분별로 생성된 일자료를 이용하여 공주지점의 월별, 분기별, 년도별 유출량을 산정하였다. 이 결과는 금강유역에 이미 구축되어있는 SSARR모형을 기반으로 한 RRFS(Rainfall Runoff Forecasting System, 유출예측 시스템)의 결과 및 관측치와 비교되었다. 계산결과 RRFS에 의한 유출량과 대청-공주구간의 유출성분분리에 의한 유출량은 관측값과 전반적으로 근사함을 확인하였으며, 검증지점의 정확한 유출율을 산정할 수 있다면, 관측자료의 연속성 및 신뢰도를 파악하는 척도를 제공할 수 있을 것으로 판단된다.측결과 있는 대상유역에 대한 적용이 요구된다.-Moment 방법에 의해 추정된 매개변수를 사용한 Power 분포를 적용하였으며 이들 분포의 적합도를 PPCC Test를 사용하여 평가해봄으로써 낙동강 유역에서의 저수시의 유출량 추정에 대한 Power 분포의 적용성을 판단해 보았다. 뿐만 아니라 이와 관련된 수문요소기술을 확보할 수 있을 것이다.역의 물순환 과정을 보다 명확히 규명하고자 노력하였다.으로 추정되었다.면으로의 월류량을 산정하고 유입된 지표유량에 대해서 배수시스템에서의 흐름해석을 수행하였다. 그리고, 침수해석을 위해서는 2차원 침수해석을 위한 DEM기반 침수해석모형을 개발하였고, 건물의 영향을 고려할 수 있도록 구성하였다. 본 연구결과 지표류 유출 해석의 물리적 특성을 잘 반영하며, 도시지역의 복잡한 배수시스템 해석모형과 지표범람 모형을 통합한 모형 개발로 인해 더욱 정교한 도시지역에서의 홍수 범람 해석을 실시할 수 있을 것으로 판단된다. 본 모형의 개발로 침수상황의 시간별 진행과정을 분석함으로써 도시홍수에 대한 침수위험 지점 파악 및 주민대피지도 구축 등에 활용될 수 있을 것으로 판단된다. 있을 것으로 판단되었다.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 전략을 개발 및 활용할 수 있으며, 특히, 한국주식시장에 적합한 거래전략은 반전거래전략이고, 이 전략의 유용성은 투자자가 설정한 투자기간보다 더욱 긴

• Cartoon and Animation Studies
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• s.16
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• pp.223-243
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• 2009

Computer graphic where the most useful and effective production methods are used for animation or films has expanded into actors' performance beyond object expression, background expression and special effect. Unlike 2D drawing software focusing on user's sense, 3D mainly depends on hardware performance and software functions. Therefore, for 3D users, learning 3D functions is directly related to new expression, and quick learning and effective representation are keys to productivity growth in animation industry. In line with industrial needs, basic 3D animation software training is provided in school. Unfortunately, however, many problems such as lack of professional instructors, time allocation and education environment prevent various 3D animation software from being taught. Moreover, functional use does not live up to industrial rapid trends. In order to improve effects of software functional education in restricted education fields, this research aims to find out what functions of 3D animation software are used in industries, what are those function used for, and how schools provide 3D animation software training.

• Journal of Korean Society of Transportation
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• v.21 no.5
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• pp.31-40
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• 2003

Unsignalized intersections are classified into two-way-stop-controlled(TWSC) and all-way-stop-controlled(AWSC) intersections for the analysis of capacity and level of service. There is no AWSC intersection in Korea, but non-controlled intersections are common. Non-controlled intersections are operated only by the driver's decision without any control. However, the study for the analysis of capacity and level of service of the non-controlled intersection has been rare. As the first stage research, this study aims to determine the measure-of-effectiveness (MOE) for the performance evaluation of non-controlled intersections. The relationships between traffic volume and the intersection passing time (delay) and number of conflicts on each intersection are analyzed. It was found that the number of conflicts were more sensitive to the traffic volume compared with the delay. It means that number of conflicts can be the MOE for the performance of non-controlled intersection. The analysis of the number of conflicts and traffic volume showed a linear relationship, so that traffic volume can also be an MOE. The level of service of non-controlled intersection can be determined with either of the MOE's. Since the performance is also influenced by the ratio of traffic volumes of crossing streets, the traffic volume should be adjusted by the ratio. The capacity of non-controlled intersection was suggested to be 2,000veh/hr referring that of AWSC intersection in the USHCM. The criteria was suggested by evenly dividing the traffic volumes based on the capacity.

• Journal of Korean Society of Transportation
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• v.18 no.5
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• pp.7-16
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• 2000

This paper is focused on verifying time-space repetition of the highway accident and finding the their causes and deterrents. We classify all months into several seasonal groups, develop the model for each seasonal group and analyze the results of these models for Joong-bu highway. The existence of seasonal effect is verified by the analysis or self-organizing map and the accident indices. Agglomerative hierarchical cluster analysis which is used to decide the seasonal groups in accordance with accident patterns, winter group, spring-fall group. and summer group. The accident features of winter group are that the accident rate is high but the severity rate is low. while those of summer group are that the accident rate is low but the severity rate is high. Also, the regression model which is developed to identify the accident Pattern or each seasonal group represents that the season-related factors, such as the amount of rainfall, the amount of snowfall, days of rainfall, days of snowfall etc. are strongly related to the accident pattern of evert seasonal group and among these factors the traffic volume, amount of rainfall. the amount of snowfall and days of freezing importantly affect the local accident Pattern. So, seasonal effect should be considered to the identification of high-risk road section. the development of descriptive and Predictive accident model, the resource allocation model of accident in order to make safety management plan efficient.