• 방송공학회논문지
• /
• 제24권7호
• /
• pp.1259-1265
• /
• 2019

Maintaining timing relationships among packets in a single media stream or between packets from different media streams is an essential criterion in MMT system. It is the function of the synchronization and de-jittering algorithms to re-adjust timing relationship between the MMT packets to assure synchronized playback. Thus, delivery of time constrained MPEG media on time, according to their temporal requirements, is an important goal of MMT. For this purpose MMT needs to specify syntax and semantics of a timing model to be used by the delivery functions. In this paper, we propose a proper timestamp-related header format for MMT delivery timing model to support media synchronization in various delivery scenarios including hybrid delivery.

• 한국자동차공학회논문집
• /
• 제5권2호
• /
• pp.94-110
• /
• 1997

In the present study, a mean torque predictive model has been proposed and experimentally validated. It includes induction air mass model, fuel delivery model and mean production mode. Air induction and fuel delivery model considering dynamic behaviors of air induction and fuel delivery were proposed to predict the air-fuel ratio excursions under transient condition. Torque function model reflects thermal efficiency, volumetric efficiency, friction and effect of spark timing. In the spark timing model, knock limit and acceleration retard are included. Experiments were carried out to validate the simulation model for the step changes of throttle at constant engine speed. The results show reasonable agreements between simulation and experiment at fully warmed condition. Using this model, fueling strategies are varied with fast throttle open and it can predict air-fuel ratio excursion and IMEP.

• Journal of Advanced Marine Engineering and Technology
• /
• 제19권3호
• /
• pp.24-32
• /
• 1995

The scavenging characteristics have a great influence on the performance of a diesel engine, especially slow-speed two-stroke diesel engines which are usually used as a marine propulsion power plant, and they are greatly affected by the conditions in the cylinder, intake and exhaust manifolds, and the opening and closing timing of scavenging ports or exhaust valves during the gas exchange process. Besides, there are many other factors to affect the scavenging characteristics and these factors interact each other very complicatedly. Therefore the simulation program of the gas exchange process is very useful to improve and predict the scavenging characteristics, due to the high costs associated with redesign and testing. In this paper it was attenpted to investigate the effect of the variation of the pressure ratio of intake to exhaust manifolds, and the variation of the opening and closing timing of a exhaust valve by using a computational program for a three-zone scavenging model which was developed by authors. The computed results showed that the scavenging efficiency and delivery ratio increased considerably, but the trapping efficiency decreased with increasing of the pressure ratio of intake to exhaust manifolds. The scavenging efficiency, trapping efficiency, and th conditions of the cylinder gases were affected by the opening timing of the exhaust valve, but the delivery ratio by the closing timing.

• 산업경영시스템학회지
• /
• 제44권3호
• /
• pp.106-116
• /
• 2021

This paper considers a joint problem for blood inventory planning at hospitals and blood delivery planning from blood centers to hospitals, in order to alleviate the blood service imbalance between big and small hospitals being occurred in practice. The joint problem is to determine delivery timing, delivery quantity, delivery means such as medical drones and legacy blood vehicles, and inventory level to minimize inventory and delivery costs while satisfying hospitals' blood demand over a planning horizon. This problem is formulated as a mixed integer programming model by considering practical constraints such as blood lifespan and drone specification. To solve the problem, this paper employs a Lagrangian relaxation technique and suggests a time efficient Lagrangian heuristic algorithm. The performance of the suggested heuristic is evaluated by conducting computational experiments on randomly-generated problem instances, which are generated by mimicking the real data of Korean Red Cross in Seoul and other reliable sources. The results of computational experiments show that the suggested heuristic obtains near-optimal solutions in a shorter amount of time. In addition, we discuss the effect of changes in the length of blood lifespan, the number of planning periods, the number of hospitals, and drone specifications on the performance of the suggested Lagrangian heuristic.

• 한국경영과학회:학술대회논문집
• /
• 대한산업공학회/한국경영과학회 2006년도 춘계공동학술대회 논문집
• /
• pp.159-166
• /
• 2006

The aim of synchronization of production and transportation planning in the supply chain is to increase the flexibility and to decrease various costs. The suggested model in this study synchronizes the timing to supply to a downstream manufacturer directly after production and to be consumed in a downstream manufacturer right after receipt. This model deals with the frequent delivery in small amount which is a new trend of the transportation not governed the economy of scale principle. Moreover, various types of transportation governed by the economy of scale principle or not are considered. Then, the two-phase mathematical model is suggested to obtain optimal job sequence and production quantity for each tasks. But, it is difficult to gain optimal solutions if there is a transportation governed by the economy of scale principle in the supply chain, or the size of the problem is increased. Thus, heuristic algorithms based on simulated annealing and genetic algorithm are suggested to find good solutions in the reasonable time.

• 패션비즈니스
• /
• 제25권1호
• /
• pp.96-107
• /
• 2021

The purpose of this study was to determine how to visualize classic makeup through Korean visual language in old literature. It provides consumers with creativity to understand and communicate and proposes a new conceptual visualization model. The research method was carried out by drawing from old literature studies, previous reproduction records, examples, and international standard diagram text language expression. First, the visualization work expressed in visual language in old literature was an objective and efficient method of information delivery as a characteristic of information design. Second, visual language expressed in old documents could be divided into makeup materials and actions. Also, the diagrams were appropriate for visualizing materials and materials for storytelling. Third, in the visualization of Korean classic makeup in old literature, images were more appropriate than diagrams in the case of action. The researcher proposed a method of visualizing historical knowledge that went one step beyond the existing simple event timing method. Timeline, correlation diagram, image, and text were combined in various ways to find the most effective historical knowledge visualization method. The representation of Korean classic makeup goes beyond the meaning of language or text and is the cultural content of re-creation, which requires systematic globalization.

• 한국CDE학회논문집
• /
• 제15권6호
• /
• pp.425-439
• /
• 2010

The current challenge with which most shipyards are forced is to reduce the design time and the time-to-delivery because of explosive order of shipbuilding. Collaborative design and product data management have become important to reduce the lead time. Furthermore, enterprise information technologies such as ERP (Enterprise Resource Planning), SCM (Supply Chain management), and APS (Advanced Planning System) requires the collaborative environment. Also, manufacturing environment has been considered as a topic of strategic interest to get shorter product lifecycles in shipyards. Most shipyards have chosen an environment of ETO (Engineering To Order) strategy which designs and produces new products in response to various requirements of customer, rules and regulations. In the ATO (Assemble 10 Order) environment, most component parts have been designed to be procured or produced on the order requirement. The basic distinction between the ETO and ATO is the timing of the design. Thus in the ATO environment, it is more flexible in reducing the lead time to meet the specified requirements of customers. However, the ETO strategy requires new ship design process and ship product structures that are linked with the implementation of PLM. And, the function and architecture of current PLM solution has been designed based upon ATO environment properly. This paper presents the PLM architecture which effectively reflects the characteristics of shipbuilding. 4-layer architecture model is suggested to implement the PLM system. Also, implemented functions of ship PLM is explained in order to make a practical guidance for ship PLM implementation.

• 대한감각통합치료학회지
• /
• 제17권1호
• /
• pp.43-53
• /
• 2019

목적 : 본 연구는 주의력결핍과잉행동장애아동(Attention Deficit Hyperactivity disorder; ADHD)을 대상으로 국내에서 제공되는 중재 방법을 체계적으로 고찰하여 최신의 국내 치료 경향을 제시하고자 하였다. 연구방법 : 2004년 1월부터 2018년 12월까지 최근 15년간 국내 학회지에 게재된 연구를 대상으로 하였다. 누리미디어(DBpia), 스콜라(Scholar), 학술연구정보서비스(RISS), 한국학술정보(KISS)에서 '주의력결핍과잉행동', '아동', '중재'를 키워드로 검색하였다. 연구대상으로 선정된 연구는 총 14개로, 각 연구는 근거의 질적 수준과 방법론적 질적 수준으로 분석한 후 그 결과를 대상자, 중재, 대조, 결과의 순으로 제시하였다. 결과 : 분석 결과 근거기반 실행의 질적 수준은 수준 IV의 연구가 가장 많았고, 방법론적 질적 수준은 '보통'의 연구가 가장 많았다. 중재는 상호작용식 메트로놈 중재(Interactive metronome; IM)의 빈도가 가장 높았고, 측정된 평가도구는 상호작용식 메트로놈 전체형 검사(Long form assessment of IM), 아동 청소년 행동평가척도(Korean behavior child checklist; K-CBCL)의 사용이 높았다. 중재결과 ADHD아동의 집중력, 과잉행동, 과제 수행, 과다언어 사용, 그리고 타이밍 등에서 유의한 효과가 나타났다. 결론 : 국내 ADHD아동을 대상으로 다양한 중재방법이 제공되었고, 그 결과 ADHD증상에서 효과적인 결과가 나타났다. 따라서 본 연구결과는 임상에서 근거기반 실행을 위한 기초자료로 사용할 수 있다. 앞으로 ADHD아동을 대상으로 한 지속적인 연구가 이루어져야 할 것이다.

• Journal of Hospice and Palliative Care
• /
• 제20권3호
• /
• pp.177-187
• /
• 2017

목적: 2017년 8월부터 말기 암 이외에도 후천성 면역결핍 증후군, 만성 폐쇄성 폐질환, 간경화 환자들에게도 호스피스 완화의료가 적용될 예정이다. 이에 본 연구에서는 비암성 질환 전문가들을 대상으로 세 가지 질환에서의 호스피스 완화의료의 목표, 내용 및 적용 방법에 대한 심층 면담을 통해, 호스피스 완화의료에 대한 생각, 인식, 태도에 대해 살펴보아, 국내 실정에 맞는 비암성 호스피스 완화의료 진료 모델 마련에 기여하고자 하였다. 방법: 본 연구는 반구조적 심층 면담조사를 통한 질적 연구이다. 암환자의 호스피스 완화의료를 담당하는 네 명의 임상 의사가 85편의 문헌 검색을 통해 핵심 질문을 선정하여 총 11명의 비암성 질환 전문가들에게 면담을 하고 질적 연구 방법에 따라 분석되었다. 결과: 전문가들은 비암성 질환의 말기환자를 정의하기 어렵다고 하였고, 호스피스 완화의료의 목표와 내용은 암환자들을 대상으로 한 것과 다르지 않다고 하였지만, 통증보다는 다른 신체 증상과 정서적 문제에 중점을 두어야 한다고 하였다. 또한, 말기라고 진단할 수 있는 시점에 호스피스 완화의료를 적용해야 한다고 하였다. 질환 별로 특수한 점들(AIDS 환자들의 항바이러스제 사용, COPD 환자들의 호흡곤란, LC 환자들의 간이식)과 의료진들에 대한 교육의 필요성에 대해 언급하였다. 호스피스 완화의료 적용 시 환자들이 자신을 포기한다는 느낌을 받을 수 있다고 하였고 정부의 재정 지원 문제에 대해서도 언급하였다. 결론: 비암성 질환에 대한 호스피스 완화의료 도입의 문제점을 최소화하기 위해서는 심도 있는 논의를 통해 비암성 질환의 말기환자에 대한 정의를 마련해야 할 필요가 있다. 또한, 비암성 말기환자들을 돌보는 의료진과 현재 말기 암환자의 호스피스 완화의료를 담당하고 있는 인력의 협력이 필요하다.