• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.282-286
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• 2005

Contents of these treatise propose method to embody station addition and passivity point correction. That store in TCMS's memory being downloaded all train running path data that is consisted of name of station and station code, departure station, destination station, train number, running time through PCMCIA memory card. Search relevant running path data and current station, destination station, the next station start time present to TCMS's display. In case it is no received information of station, device that do function of passenger broadcasting and pilot light does not act. This time, if input information of current station, relevant device does point revision.

• 동력기계공학회지
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• 제18권4호
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• pp.11-16
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• 2014

Although smoke emitted from ships is not included in IMO(International Maritime Organiztion) regulation yet, it is one of the substance what is polluting mainly the air. Especially, its concentration is very high when an engine is started and a load is rapidly changed. This is caused by unburned fuel what is injected more than necessary quantity after combustion period. It is possible to decrease smoke concentration emitted at starting engine by controlling fuel injection quantity, but it is concerned that time to rated speed must be spent. Then a governor what can reduce the smoke concentration without a loss of time to rated speed is needed. We adopted a electro-hydraulic governor what can control dual fuel start limit function and achieved very low level of smoke concentration without greater the loss of time to rated speed.

• 설비공학논문집
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• 제16권10호
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• pp.990-998
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• 2004

Dynamic behavior of an ammonia-water absorption system was investigated numerically. Thermal-hydraulic model for a single-effect 3 RT chiller was developed by applying transient conservation equations of total mass, $NH_3$ mass, energy and momentum to each component. Transient variations of system properties and transport variables were analysed during start-up operation. Numerical analyses were performed to quantify the effects of bulk concentration and charging ratio on the system performance in terms of cooling capacity, coefficient of performance, and time constant of system. For an absorption chiller considered in the present study, optimum charging ratio and bulk concentration were to found to exist, which resulted in the maximum cooling capacity and COP. The time constant increased as the charging ratio increased, but decreased with the increase of bulk concentration.

• 산업공학
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• 제24권4호
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• pp.281-294
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• 2011

This paper considers the rail crane scheduling problem which is defined as determining the sequence of loading/unloading container on/from a freight train. The objective is to minimize the weighted sum of the range of order completion time and makespan. The range of order completion time implies the difference between the maximum of completion time and minimum of start time of each customer order consisting of jobs. Makespan refers to the time when all the jobs are completed. In a rail freight terminal, logistics firms as a customer wish to reduce the range of their order completion time. To develop a methodology for the crane scheduling, we formulate the problem as a mixed integer program and develop three metaheuristics, namely, genetic algorithm, simulated annealing, and tabu search. To validate the effectiveness of heuristic algorithms, computational experiments are done based on a set of real life data. Results of the experiments show that heuristic algorithms give good solutions for small-size and large-size problems in terms of solution quality and computation time.

• Design & Manufacturing
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• 제14권4호
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• pp.25-39
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• 2020

In this study, an edge device that monitors the injection molding process by measuring the mold vibration(acceleration) signal and the mold surface temperature was developed and evaluated its performance. During injection molding, signals of the injection start, V/P switchover, and packing end sections were obtained through the measurement of the mold vibration and the injection time and packing time were calculated by using the difference between the times of the sections. Then, the mold closed and mold open signals were obtained using a magnetic hall sensor, and cycle time was calculated by using the time difference between the mold closed time each process. As a result of evaluating the performance by comparing the process data monitored by the edge device with the shot data recorded on the injection molding machine, the cycle time, injection time, and packing time showed very small error of 0.70±0.38%, 1.40±1.17%, and 0.69±0.82%, respectively, and the values close to the actual were monitored and the accuracy and reliability of the edge device were confirmed. In addition, it was confirmed that the mold surface temperature measured by the edge device was similar to the actual mold surface temperature.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제15권11호
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• pp.3913-3934
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• 2021

Real-time prediction of Web service of quality (QoS) provides more convenience for web services in cloud environment, but real-time QoS prediction faces severe challenges, especially under the cold-start situation. Existing literatures of real-time QoS predicting ignore that the QoS of a user/service is related to the QoS of other users/services. For example, users/services belonging to the same group of category will have similar QoS values. All of the methods ignore the group relationship because of the complexity of the model. Based on this, we propose a real-time Matrix Factorization based Clustering model (MFC), which uses category information as a new regularization term of the loss function. Specifically, in order to meet the real-time characteristic of the real-time prediction model, and to minimize the complexity of the model, we first map the QoS values of a large number of users/services to a lower-dimensional space by the PCA method, and then use the K-means algorithm calculates user/service category information, and use the average result to obtain a stable final clustering result. Extensive experiments on real-word datasets demonstrate that MFC outperforms other state-of-the-art prediction algorithms.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제15권7호
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• pp.505-509
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• 2009

실시간 처리의 가장 큰 목적은 시스템에서 동작 하는 실시간 태스크들이 주어진 데드라인을 잘 지키도록 하는 것이다. 본 논문에서는 임베디드 시스템을 위한 운영체제인 TMO-eCos의 실시간 태스크 스케줄링 성능 개선을 위하여, TMO(Time-triggered Message-triggered Object) 모델에 필수 요소로 규정된 BCC(Basic Concurrency Control) 스케줄러의 구현과, 실시간 객체 TMO의 객체 기반 프로그래밍을 제공하는 TMO 지원 라이브러리의 설계 및 구현에 관하여 기술한다. BCC 스케줄러는 보장성 컴퓨팅 설계를 위한 것으로, 비동기적 사건 구동 태스크의 스케줄을 사전에 스케줄이 정의된 시간 구동 태스크의 구동 시간을 제외한 여유 시간이 충분할 때에만 허용하는 실시간 스케줄러이다.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.61-66
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• 2004

In this paper an effort is made to develop an innovative spatial arrangement concept pertaining to ship building industry. The spatial scheduling is the problem that concentrates on effective planning of available space and arrangements of blocks and in a priority manner. In order to create an effective spatial scheduling. a database providing the priority has to be available to make the erection sequence. Such a system works hand in hand with erection sequence generator program The erection sequence program works on the conventional network analysis method which uses a typical parent-children idea for the calculation of the ENT(possible earliest network start time) and LNT(possible latest network start time). This program works in a cyclic manner taking turns by calculating the ENT in upward trace and LNT on the return trace thereby generating the entire erection sequence diagram for the requisite problem The generated database serves as an input data for spatial scheduling problem. When the system works it takes into consideration the entire system based on heuristic concepts as mentioned. There system uses the spatial aspects such as the available area of the P. E area and plan area of the corresponding blocks and its priority of erection from the erection sequence generator program develops the spatial scheduling arrangement. In this paper using all these concepts an innovative spatial schedule development system developed.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제4권9호
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• pp.289-296
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• 2015

정보의 폭발적인 증가로 사용자들은 원하는 정보를 빠른 시간에 얻는 것이 힘들어졌다. 따라서 이 문제를 해결하기 위한 다양한 방식의 새로운 서비스들이 제공되고 있다. 개인에게 맞는 맞춤 서비스를 제공하는 것이 중요하게 부각되면서 개인화 추천 시스템이 매우 중요하게 되었다. 추천 시스템 중 협업 필터링은 추천 시스템에서 널리 사용되고 있고 개인화 추천 시스템 중에서 가장 성공적인 방법이다. 협업 필터링 방법은 고객들의 프로파일 정보를 기반으로 추천을 하므로 희박성 문제와 cold-start 문제가 있다. 본 논문에서는 개인에게 더 정확하게 추천하기 위해 협업 필터링 기법과 상황기반 기법을 함께 이용하는 방법을 제안한다. 상황기반 기법은 사용자를 둘러싼 시간, 감정, 장소 등과 같은 환경을 고려하여 사용자에게 맞는 아이템을 추천하는 방법으로 상황에 따라 달라지는 사용자의 선호도를 반영할 수 있다. 본 논문에서는 상황기반 기법을 활용하기 위해 상황정보로 감정을 이용하며 이를 위해 개인의 주관적인 정보를 파악하는 데 효과적인 영화 리뷰를 이용한다. 본 논문에서 제안한 방법은 기존의 협업 필터링 방법보다 성능평가 결과, 향상된 성능을 보였다.

• Nutrition Research and Practice
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• 제14권6호
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• pp.654-666
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• 2020

BACKGROUND/OBJECTIVES: This study aimed to evaluate how breastfeeding and complementary nutrition practices of mothers of 0-24-month-old children comply with the World Health Organization (WHO) recommendations for infant and young child feeding and to compare the results with selected demographic parameters related to the mother and child. SUBJECTS/METHODS: The research sample comprised mothers (n = 250) with children less than 2 years old. Data were obtained via questionnaire and were analyzed using SPSS 20.0 package program. The Pearson χ² or Fisher's exact tests were used for assessing relationships between categorical variables. The one-sample t-test was used for comparisons with reference values. RESULTS: Most mothers (97.2%) breastfed their babies immediately after birth. The mean time to breastfeeding after delivery was 47.8 ± 14.8 minutes, and 40.8% of the mothers complied with the WHO recommendation. Furthermore, 59.8% of the mothers exclusively breastfed their children for 6 months (mean 5.2 ± 1.5 months). The mean duration to the start of providing complementary food was 5.8 ± 0.6 months, and 76.1% of mothers who complied with the WHO recommendation. Only 12.3% of mothers breastfed their children for at least 12 months (mean 7.7 ± 3.3 months). On average, mothers gave cow milk to their children for the first time at 10.1 ± 1.7 months and honey at 11.8 ± 2.3 months. The mothers' rates of compliance with the WHO recommendations on cow milk and honey feeding were 32.0% and 71.6%, respectively. The rate of mothers who complied with the WHO minimum meal frequency recommendation was 88.3%. CONCLUSIONS: We suggest that the WHO recommendations on this subject will be realized more fully by emphasizing the importance of the positive effects of breastfeeding until the age of 2 years and of a timely start of complementary food provision. Such changes will affect child health over the long term.