• The Journal of Information Systems
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• v.18 no.3
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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.

• ETRI Journal
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• v.32 no.2
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• pp.241-247
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• 2010

We propose and experimentally demonstrate a service-aware optical transport system. The proposed service-aware optical transport system makes a flow based on service type and priority of traffic. The generated flow is mapped to a corresponding sub-${\lambda}$ for transport over an optical network. Using sub-${\lambda}$ provided by the centralized control plane, we could effectively provide quality-of-service guaranteed Ethernet service and best-effort service simultaneously in a single link. The committed information rate (CIR) traffic and best-effort traffic are assigned to different sub-${\lambda}s$. The bandwidth of the CIR traffic is guaranteed without being affected by violation traffic because the bandwidth is managed per each sub-${\lambda}$. The failure detection time and restoration time from a link failure is measured to be about 60 ${\mu}s$ and 22 ms, respectively, in the ring network. The measured restoration time is much smaller than the 50 ms industry requirement for real-time services. The fast restoration time allows the proposed service-aware optical transport system to offer high availability and reliability which is a requirement for transport networks.

• 한국정보통신설비학회:학술대회논문집
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• 2007.08a
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• pp.89-91
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• 2007

Multimedia service based on interactivity, personalization, multiple channels and community distinguishes IPTV from incumbent TV. But data encoding/decoding time and image frame processing should be considered in digital TV versus analog device. Especially channel zapping time is one of the most important parameters for the service quality of IPTV. This paper proposes the mechanism for decreasing the channel zapping time with multiple decoder and image frame processing. We also implemented the multi-group video community service system using IP multicasting function supporting interactive learning service.

• IEMEK Journal of Embedded Systems and Applications
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• v.2 no.2
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• pp.95-100
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• 2007

Recently ubiquitous application services are developed plentifully using RFID techniques in the field of distribution and security industries. However, except these field the applications using RFID are not mature yet. In this study, we proposed a real-time context service model of the u-conference based on the real-time contextual information acquired from conference and exposition. With collection of real-time contextual information for u-conference, the model can provide a lot of information services on the state of session attendee, doorway control, affairs, user certification, presentation progress etc. For the verification of proposed real-time context service model of u-conference, we design and implement the conference progress state service included the state of session attendee, user certification and presentation progress etc. This service provides the presentation state information included the current presenter, the paper list, the number of session attendee, the schedule and place of each session using the collecting RFID tag and the related information.

• Korean Journal of Veterinary Service
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• v.15 no.2
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• pp.128-133
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• 1992

To obtain the basic data for blood chemistry, the effects of the time elapse of serum separation on bovine blood chemical values were investigated. The results obtained are summerized as follows : 1. The constant fluctuation tendency and significance was not detected in GOT, GPT, BUN, Creatinine, ALP, CPX, Cholesterol, Ca, Mg and Pi. 2. Glucose showed the decrease tendency according to the time elapse of serum separation. As the values at 12 and 24 hours showed significant lower values than those at 1 and 2 hours (p＜0.01) it was thougth that separation time of serum should be focussed for the glucose determination.

• Review of KIISC
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• v.11 no.6
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• pp.24-30
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• 2001

Time stamping service는 데이터가 특정 시점에 존재하였다는 증거를 신뢰할 수 있는 제3의 기관(Trusted Third Party) 이 제공해주는 서비스로서 e-Business가 활성화되면서 그 필요성이 부각되고 있는 서비스이다. Time stamping service 관련 기술은 ISO/IEC JTCl SC27 WG2에서 표준화 작업이 진행되고 있으며 IETF PKIX WG에서는 RFC 3161로 표준문서가 나와있다. 본 고에서는 현재 표준 작업이 진행되고 있는 ISO/IEC JTC1 SC27의 time stamping service 기술을 중심으로 서비스 개요와 지난 2001. 10.16(화)∼19(금) 서울에서 개최된 23차 SC27 기술 표준 회의에서 논의된 주요 쟁점 사항을 정리한다.

• Korea Journal of Hospital Management
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• v.14 no.3
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• pp.132-153
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• 2009

The waiting time makes the customer be bored, and is the reason to obstruct the service quality evaluation. The managing waiting time appears to be the most important task, in accordance of physical inconvenience especially because the customers of the medical service are supplied in the unstabled status. Therefore, necessity and object of managing waiting time in the medical service were presented through the definition of waiting time and the consideration about preceding study, and the main cause of the waiting time was analyzed, furthermore the measure of actually indicated waiting time and various ideas for reducing the time were presented lastly as selecting a case study participative hospital for achieving the study object. This study will be one of role model as a solution to reduce the waiting time in each medical institution.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.20 no.42
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• pp.31-38
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• 1997

The main objective of this research is to develop a model to select the optimal input service level for a distribution center - multi branch inventory distribution system. With the continuous review policy, the distribution center places an order for specific order quantity to an outside supplier, and the order quantity is replenished after a certain lead time. Also, each branch places an order for particular order quantity to the distribution center to satisfy the customer demands, and receives the replenishment after a lead time. When an out of stock condition occurs during an order cycle, a backorder is placed to the upper level to fill the unfilled demands. With these situation, variable demand and variable lead time are used for better industrial practice. Further, actual lead times with a generic lead time distribution are used in developing the control model. Under the actual lead time model, the customer service measures actually attained for the distribution center and each branch are explained as the effective customer service measures. Thus, throughout the optimal control (using computer search procedures), we can select the optimal input service levels for the distribution center and each branch to attain the effective service level for each branch which is consistent with the goal level of service for each branch. At the same time, the entire distribution system keeps minimum inventories.

• Journal of the Korea Safety Management & Science
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• v.3 no.3
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• pp.55-64
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• 2001

The main objective of this research is to develop a model to select the optimal input service level for a distribution center-multi branch inventory distribution system. With the continuous review policy, the distribution center places an order for specific order quantity to an outside supplier, and the order quantity is replenished after a certain lead time Also, each branch places an order for particular order quantity to the distribution center to satisfy the customer demands, and receives the replenishment after a lead time. When an out of stock condition occurs during an order cycle, a backorder is placed to the upper level to fill the unfilled demands. With these situation, variable demand and variable lead time are used for better industrial practice. Further, actual lead times with a generic lead time distribution are used in developing the control model. Under the actual lead time model, the customer service measures actually attained for the distribution center and each branch are explained as the effective customer service measures. Thus, throughout the optimal control (using computer search procedures), we can select the optimal input service levels for the distribution center and each branch to attain the effective service levels for each branch which is consistent with the goal level of service for each branch. At the same time, the entire distribution system keeps minimum inventories.

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.1
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• pp.55-60
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• 2011

The mobile internet telephony service rapidly grows according to the extending deployment of smartphones. Unlike telephony service over a conventional public switched telephone network (PSTN) or mobile network, internet telephony service cannot guarantee its service quality, which can be severer in a wireless environment. Therefore, a more strict and systematic quality management is required for successful settlement and popularization of mobile internet telephony service. Existing quality management scheme using a specific measurement equipment cannot measure all the time so that it performs late management. In order to overcome the problem, this paper develops a software that can be equipped on a user terminal and measures the service quality all the time. By using the developed software, all-time and user-activating service quality monitoring can be supported.