PURPOSES : This paper proposes an artificial neural network (ANN)-based real-time traffic signal time design model using real-time field data available at intersections equipped with smart intersections. The proposed model generates suitable traffic signal timings for the next cycle, which are assumed to be near the optimal values based on a set of counted directional real-time traffic volumes. METHODS : A training dataset of optimal traffic signal timing data was prepared through the CORSIM Optimal Signal Timing program developed for this study to find the best signal timings, minimizing intersection control delays estimated with CORSIM and a heuristic searching method. The proposed traffic signal timing design model was developed using a training dataset and an ANN learning process. To determine the difference between the traditional pre-time model primarily used in practice and the proposed model, a comparison test was conducted with historical data obtained for a month at a specific intersection in Uiwang, Korea. RESULTS : The test results revealed that the proposed method could reduce control delays for most of the day compared to the existing methods, excluding the peak hour periods when control delays were similar. This is because existing methods focus only on peak times in practice. CONCLUSIONS : The results indicate that the proposed method enhances the performance of traffic signal systems because it rapidly provides alternatives for all-day cycle periods. This would also reduce the management cost (repeated field data collection) required to increase the performance to that level. A robust traffic-signal timing design model (e.g., ANN) is required to handle various combinations of directional demands.

본 연구는 일정 수준의 중국어 실력을 갖춘 학생들이 기업체와 연계하여 진행한 중국어 캡스톤디자인 교육과정에 대한 사례연구이다. 본 캡스톤디자인 교육과정에서 는 제품소개서 중국어 번역과 연계된 기업의 중국 진출을 위한 마케팅 계획 수립을 프로젝트 과제로 설정하여 진행하였다. 프로젝트 과제를 수행하면서 경영 및 마케팅 관련 이론과 경험이 부족한 어학 전공자들이 마케팅 전략을 세우고 분석할 때의 한 계점도 있었지만, 대부분 고급 중국어가 가능한 학생들이 참여하였기 때문에, 중국어 로의 제품소개서의 번역과 함께 중국 시장조사와 마케팅 전략 수립 시 한국 자료에 의존하지 않고 중국 공공기관에서 발표하는 원문 자료를 찾고 해독하고 취합하여 정 리해 내는 역량은 경영학도들에 비해 훨씬 뛰어나다는 것을 발견할 수 있다.

This study aimed to examine the operations of school food services to prevent the spread of coronavirus disease 2019 (COVID-19) in schools nationwide. The survey data on school food service operations targeting nutrition teachers and nutritionists at 1,023 schools in 2020 and 1,177 schools in 2021 were used. The year 2021 saw an increase compared to 2020 in the following: ‘average days to be served with meals for a year (144.5 vs. 184.7)', 'provided meals to all students (92.3% vs. 96.6%)', 'utilization of additional staff for foodservice assistance (33.4% vs. 38.8%)', 'installation of partitions (61.2% vs. 83.8%)', 'provision of general diet (96.1% vs. 99.1%)', and 'use of kitchen utensils (91.3% vs. 95.1%)', 'use of cafeteria water cup (9.9% vs. 31.0%)' and 'use of drinking water in school (46.8% vs. 52.1%)'. Compared to 2020, in 2021, it was confirmed that the school food service operations stabilized due to the increase in the normal school attendance rate and that systems were in place for operations during the COVID-19 pandemic. In the future, it will be necessary to develop manuals and special recipes necessary for responding to infectious diseases, and to operate a manpower pool that can quickly find replacement personnel if required.

Purpose: This study aimed to examine the learning immersion, learning satisfactory, and learning confidence differences after virtual and then laboratory simulations. Methods: A two-group cross-over design was used, and the participants included 148 senior nursing students (74 teams). The treatments had virtual and then laboratory simulations. The data were analyzed using independent t-test, repeated measures ANCOVA and Chronbach’s αcoefficient using the SPSS/ WIN 21.0 program. Results: Nursing students who experienced laboratory simulation after virtual simulation were different totally or partially with nursing students who experienced virtual simulation first in learning immersion, learning satisfaction and, learning confidence. Conclusion: Effects based on order of simulation were different. To increase learning immersion, laboratory simulation was done before virtual simulation. Learning satisfaction and learning confidence, it were not affected by order of simulation type but by number. Repeated studies require clearly investigating the effects based on order of simulation type.

Recently, small and medium-sized manufacturing companies have shown increased interest in and participation in smart factories in order to survive in market competition. However, many SMEs build smart factories without a systematic review or preparation, which leads to them not being able to use them properly. This study considers the main reason for the low utilization rate of smart factories to be a lack of sufficient reflection of user requirements. Therefore, a method and procedure for deriving the priority of smart factory requirement functions and operating performance indicators based on QFD is proposed as a solution to this issue.

PURPOSES : This study proposes a method for comparative analysis, based on geographic information systems (GIS), that can be used when introducing demand-responsive transit in areas where public transportation is not available. METHODS : To analyze areas where public transportation is neglected, bus stop location information, building location information, and administrative district boundary data for the census were acquired. Geocoding was used for address-based raw data to create a spatial database. Based on the collected data, the proportion of households separated by a certain minimum distance from a bus stop was aggregated and constructed through near analysis. When introducing a demand-responsive transit system, the operational cost was calculated and compared with the existing city bus transportation cost. RESULTS : Results show that the operating costs of introducing demand-responsive transit can be compared and analyzed using the proposed method, for a case study of Daejeon Metropolitan City. CONCLUSIONS : It is economically efficient to avoid the entry of route buses and introduce demand-responsive transit in areas isolated from public transportation where the number of people getting on and off is extremely low.

기상불량으로 인해 발생하고 있는 해양사고 중 해무 발생에 따른 시계제한은 선박의 좌초, 선저 파손 등의 사고를 유발하는 것과 동시에 사고에 따른 인명피해를 동시에 수반하고 있으며 이는 매년 지속적으로 발생하고 있다. 또한 해상에서의 저시정은 지역간 국소적으로 차이가 존재하는 경우에도 일괄적으로 여객선에 대한 운항 지연 및 통제 조치를 하고 있어 섬주민들의 교통수단 이용에 상당 한 불편을 초래하는 등의 사회적 문제로 대두되고 있다. 더욱이 이와 같은 조치는 지역적 편차나 사람마다 관측의 판단 기준이 상이하여 이를 객관적으로 정량화하지 못하고 있어 더욱 문제가 심화되고 있는 실정이다. 현재 각 항만의 VTS에서는 시정거리가 1km 미만인 경우 선박의 운항을 통제하고 있으며, 이 경우 저시정에 따른 해무 가시거리를 시정계 혹은 육안에 의한 목측(目測)에 의존하고 있을 정도로 객관적인 데이터 수집을 통한 평가에 있어서는 한계가 있다. 정부에서는 이와 같은 해양교통안전 저해요소를 해결하기 위한 일환으로 해 무 탐지 및 예측을 위한 해양기상신호표지 및 해상안개관측망을 구축하여 운용하고 있으나, 국지적으로 발생하는 해무를 관측하기 위한 시스템은 매우 부족한 현실적 어려움에 놓여있다. 이에 따라 본 논문에서는 해상에서의 저시정으로 인해 발생하고 있는 여러 사회적 문 제를 해결하기 위한 국내․외 정책동향에 대해 살펴보고, 이와 관련한 일반국민 및 현장 이해관계자의 인식 정도를 조사․분석하여 해무 에 따른 해상교통안전을 확보하기 위한 정부지원(해무 탐지 및 예측 기술을 기반으로 한 해상교통운영 체계 개발 등)의 필요성에 대한 기 초자료를 제공하고자 한다. 또한 이는 궁극적으로 해무로 인해 발생할 수 있는 해상안전 위험요소를 사전에 차단함으로써 보다 안정된 해상교통운영체계를 마련하는데 그 목적을 두고 있다.

PURPOSES : This study proposes brief guidelines for traffic engineers in the field to refer to when operating tram priority signals based on the "early green" and "green extension" methods. METHODS : A set of VISSIM simulation analyses was conducted considering various traffic and control conditions in a hypothetical corridor consisting of two signalized intersections. The traffic conditions were varied at five different levels. The control conditions were varied at twenty-five levels by changing the tram priority traffic signal control parameters, i.e., the early green unit time and green extension unit time. A total of 125 simulation runs were from these combinations. A set of optimal signal timings for ordinary non-tram vehicles was prepared with TRANSYT-7F and implemented for the simulation. A tram priority signal control module based on VISVAP was exclusively developed for this study. RESULTS : As expected, no specific trend was found in the relationship between the two tram priority control parameters (early green time and green extension time). However, a trend was observed when assuming that the early green and green extension operations were mutually exclusive. Specifically, an inverse trend appeared between the tram priority control parameter values and level of congestion according to the performance measure (average network delay). CONCLUSIONS : For the early green control parameters, it is better to provide six seconds when undersaturated and four seconds when near-saturated. For the green extension control parameter, four seconds is suitable.

In an automotive plant, an automated storage and retrieval system (ASRS) synchronizes material handling flows from a part production line to an auto-assembly line. The part production line transfers parts on small-/large-sized pallets. The products on pallets are temporarily stored on the ASRS, and the ASRS retrieves the products upon request from the auto-assembly line. Each ASRS aisle is equipped with narrow-/wide-width racks for two pallet sizes. An ASRS aisle with narrow-/wide-width racks improves both storage space utilization and crane utilization while requiring delicate ASRS aisle design, i.e., the locations of the narrow-/wide-width racks in an ASRS aisle, and proper operation policies affect the ASRS performance over demand fluctuations. We focus on operation policies involving a common storage zone using wide-width racks for two pallet sizes and a storage-retrieval job-change for a crane based on assembly-line batch size. We model a discrete-event simulation model and conduct extensive experiments to evaluate operation policies. The simulation results address the best ASRS aisle design and suggest the most effective operation policies for the aisle design.