• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.294-297
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• 2005

Time series are comprehensively appeared and developed in many applications, ranging from science and technology to business and entertainrilent. Similarity search under time warping has attracted much interest between the time series in the large sequence databases. DTW (Dynamic Time Warping) is a robust distance measure and is superior to Euclidean distance for time series, allowing similarity matching although one of the sequences can elastic shift along the time axis. Nevertheless, it is more unfortunate that DTW has a quadratic time. Simultaneously the false dismissals are come forth since DTW distance does not satisfy the triangular inequality. In this paper, we propose an efficient range query algorithmbased on a new similarity search method under time warping. When our range query applies for this method, it can remove the significant non-qualify time series as early as possible before computing the accuracy DTW distance. Hence, it speeds up the calculation time and reduces the number of scanning the time series. Guaranteeing no false dismissals, the lower bounding function is advised that consistently underestimate the DTW distance and satisfy the triangular inequality. Through the experimental result, our range query algorithm outperforms the existing others.

• 대한교통학회지
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• 제13권4호
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• pp.105-115
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• 1995

This paper deals with an operation concept of "time-transfer of buses", in which buses arrive a transfer center at the same time and allow passengers to transfer to other bus lines, so that passengerscan go anywhere all the timed-transfere buses operate with only one transfer. This timed-transfer bus system is known as an efficient operating technique which can be adopted in an area with sparsely distrubuted bus demand. A model of timed-transfer is estabilished in terms of vaious factors such as the expected(or average) arrival time, distribution of arrival time, timed-transfer cycle, shceduled departure time, etc. It is assumed that the objective of timed-transfer bus system is to minimize the total transfer waiting time. The optimal schedualed arrival time or buffer time(time required to arrive ealy in consideration of delay) is analyzed for a general case and various speicial cases. It was found that the optiaml buffer time is an inverse funcion of the timed-transfer cycl and increases with the cycle time, assumin g that there is a fixed scheduled departure time at the transfer cetner regardless of whether one or more buses fail to arrive before the scheduled departure time. If buses are to wait uhtil all the buses arrive at the transfer center, that is, the transfer departure time is vairable, the optimal scheduled arrival times can be obtained by a mathmatical programming.

• 복식문화연구
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• 제21권1호
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• pp.117-128
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• 2013

Studies show that time pressure affects the purchase decision-making process of consumers. However, in the case of apparel shopping, few studies have looked into the influence of time pressure on the purchase decision-making process. This study aims to determine how perceived time pressure in apparel shopping, time pressure situations, and product type and the interactions between these variables influence the clothing purchase process. An empirical study was conducted among males and females in their 20s and 30s. Perceived time pressure in apparel shopping was measured using four items. Time pressure situations and product types were given in the form of scenarios. A $2{\times}2{\times}2$ experimental design was used, and perceived time pressure in apparel shopping, time pressure situations, and product type were used to create eight different situations. The dependent variables included decision-making speed, anticipated regret, and anticipated purchase satisfaction. Data from 512 subjects were collected through an online data collection. Results showed that the high perceived time pressure group and the shopping situation with time pressure involved a significantly high level of decision-making time, anticipated regret, and anticipated purchase satisfaction. Marketers must understand the real-time pressure situations of consumers.

• 전기전자학회논문지
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• 제5권2호
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• pp.164-173
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• 2001

본 논문은 독립적으로 움직이면서 시간 제약을 만족시키는 새로운 내장형 실시간 시스템을 설계하며 구현하였다. 본 논문에서의 실시간 시스템 커널은 시간적인 요소를 가장 핵심으로 고려하여 설계되었다. 따라서 실시간 커널은 작은 용량을 가지며 빠르게 예측하며, 실시간 스케줄링에 요구되는 많은 변화들을 통해서 실시간 커널에 융통성을 부여한다. 제안한 실시간 커널은 경성 실시간 제약 조건인 인터럽트 지연 시간, 스케줄링의 정확성, 메시지 전달시간을 만족하기 위하여 실시간 커널에는 실시간 태스크 처리와 인터럽트 처리, 타이밍을 처리하도록 하였고 비 실시간 커널은 일반적인 태스크를 처리하도록 하였다. 제안된 실시간 시스템은 RT-Linux, QNX와 인터럽트 지연, 스케줄링 정확성, 메시지 전달시간 등을 비교 분석하여 효율성을 입증하였다.

• 한국정보시스템학회지:정보시스템연구
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• 제18권3호
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• pp.155-181
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• 2009

Modern persons should do many activities during limited time. In such situation, people feel time pressure because they think that time is short. Time pressure affects negatively several factors such as satisfaction and intention to use through perceived time cost. Ubiquity, an mobile service's characteristic in which users can use desired information or services in anywhere and anytime, would let users feel free from time pressure. This study examines the relationship between perceived time and intention to use and the moderating effect of ubiquity. We performed a survey for users of DMB service, a representative mobile service. Using Partial Least Square, we tested hypotheses. The results suggest that time pressure influences positively perceived time cost and that perceived time cost affects negatively satisfaction but not enjoyment. And the results show that there are the significant positive relationships between enjoyment and intention to use and between satisfaction and intention to use. Finally, the moderating effects of ubiquity on the relationships between perceived time cost and enjoyment and between perceived time cost and satisfaction was found to be positive and significant. We suggests implications basing on the results.

• 대한임상전기생리학회지
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• 제10권2호
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• pp.31-35
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• 2012

Purpose : The purpose of this study was to investigate the effect of kinematic variables by analysis of a gait in older. Methods : This study selected nine in older adults with osteoarthritis. The Kinematic variables during walk were compared analyzed using motion analysis. Results : The findings of this study are as follows. Stance time showed significant difference within-subject groups and interaction within-subjects and time. The swing and stride time showed a no significant interaction within-subjects and time. Swing time showed a no significant difference according to time and within-subjects. Stride time showed a significant difference according to time. But, stride time showed a no significant difference according to within-subjects. Conclusion : These findings of this study indicate that when the patients with total knee arthroplasty decreased stability. Therefore, stance and stride time showed increase when walking, because to decrease the weight bearing that is delivered to knee. And swing time showed decrease.

• 한국통신학회논문지
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• 제27권11C호
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• pp.1074-1080
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• 2002

시간을 이용한 일회용 패스워드 방식은 별도 동기가 필요 없기 때문에 클라이언트/서버 환경 등에서 특히 유용하게 사용될 수 있다. 그러나 시간을 이용한 일회용 패스워드 방식에서는 시간편차에 의한 인증 실패가 발생할 수 있다. 이 논문에서는 시간편차에 의한 인증이 실패할 가능이 있는 기간을 표시하는 1비트 정보를 이용하여, 시간편차에 의한 인증 실패가 발생하지 않는 효율적인 일회용 패스워드 알고리즘을 제안하며, 아울러 제안된 일회용 패스워드 알고리즘에 부가정보 2 비트를 추가하여 시간교정을 겸할 수 있는 알고리즘 또한 제안한다.

• 대한가정학회지
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• 제49권5호
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• pp.81-96
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• 2011

This study analyzed the time use of dual income paid workers. The data was selected from the '2009 Korean Time Use Survey' by the Korean National Statistical Office. There were 2799 respondents who were paid workers with dual income. There were big differences in time use between men and women. The result showed that men's time allocation focused on 'labor and leisure' and women's time allocation focused on ‘labor and housework'. This means the women among dual income paid workers faced difficulties in dual burden of work-family balance. Regression analysis on time use dividing men and women showed that age, education, income, working type and the presence of preschool children had significant effects on time allocation. We found the income effects on time use which reduced paid working time and increased housework and leisure time. Significantly, younger men who have preschool children spend more time in housework. We could find the possibility of a change in men's time allocation.

• 한국경영과학회지
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• 제28권2호
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• pp.75-89
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• 2003

Media Access Control (MAC) Protocol in IEEE 802.11 Wireless LAN standard supports two types of services, synchronous and asynchronous. Synchronous real-time traffic is served by Point Coordination Function (PCF) that implements polling access method. Asynchronous nonreal-time traffic is provided by Distributed Coordination Function (DCF) based on Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) protocol. Since real-time traffic is sensitive to delay, and nonreal-time traffic to error and throughput, proper traffic scheduling algorithm needs to be designed. But it is known that the standard IEEE 802.11 scheme is insufficient to serve real-time traffic. In this paper, real-time traffic scheduling and admission control algorithm is proposed. To satisfy the deadline violation probability of the real time traffic the downlink traffic is scheduled before the uplink by Earliest Due Date (EDD) rule. Admission of real-time connection is controlled to satisfy the minimum throughput of nonreal-time traffic which is estimated by exponential smoothing. Simulation is performed to have proper system capacity that satisfies the Quality of Service (QoS) requirement. Tradeoff between real-time and nonreal-time stations is demonstrated. The admission control and the EDD with downlink-first scheduling are illustrated to be effective for the real-time traffic in the wireless LAN.

• 한국게임학회 논문지
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• 제17권4호
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• pp.71-80
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• 2017

본 연구는 게임에서의 시간에 대한 내용을 담고 있다. 게임의 시간에 대한 연구는 제스퍼 주울(Juul, 2004)을 비롯한 여러 학자들을 통해 진행된 바 있으며, 기존의 연구들이 현실의 시간 개념을 기준으로 게임의 시간을 내재적 시간과 외재적 시간을 분리하여 다루고 있음을 먼저 확인하였다. 이 가운데 본 연구는 관찰자적 시각으로 게임의 내재적 시간을 고찰하고자 하는데, 이는 게임에서 가장 중요한 부분이 현실과 게임의 시간적 관계성 보다는 게임성 즉, 플레이이며 더 나아가 경험에 있다고 보기 때문이다. 따라서 본 연구는 게임의 내재적 시간을 '지향적 시간'과 '비지향적 시간'으로 분류하고 그 시간들이 게이머의 경험에서 어떤 작용을 하는지 살펴보고자 하였다.