• Proceedings of the KIEE Conference
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• 2006.04a
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• pp.300-302
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• 2006

Middleware offers function that user application program can transmit data independently of network device. Connection management about network connection of module is important for normal service of module base personal robot. Unpredictable network disconnection is influenced to whole robot performance in module base personal robot. For this, Middleware must be offer two important function. The first is function of error detection and reporting about abnormal network disconnection. Therefore, middleware need method for network error detection and module management to consider special quality that each network device has. The second is the function recovering that makes the regular service possible. When the module closed from connection reconnects, as this service reports connection state of the corresponding module, the personal robot resumes the existing service. In this paper proposed method of network connection management for to support fault tolerant about network error of network module based personal robot.

• Journal of Korea Multimedia Society
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• v.20 no.9
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• pp.1527-1540
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• 2017

Recently, due to the rapid development of the internet, the production and demand of high capacity contents are rapidly increasing. In order to accommodate the changing trend of internet usage, researches on CCN, the future internet architecture, are actively being conducted. Mobility support is an important challenge in CCN real-time services, given that today's internet environment is changing to mobile and real-time services are increasing. In CCN real-time services, the mobility problem can be largely divided into consumer mobility, provider mobility, and intermediate-node mobility. Among them, when the intermediate-node moves in the CCN real-time services, the service disconnection occurs and the QoS degradation is caused. In this paper. we propose Intermediate-Node Mobility Support(INMS) to support the intermediate-node mobility in CCN real-time services. Experimental results show that the proposed scheme shows better performance than CCN in terms of service disconnection time and packet loss.

• Proceedings of the KIPE Conference
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• 1998.10a
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• pp.547-553
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• 1998

In this paper, we composed of utility interactive pv generation system of voltage source inverter, and represented uninterrutible power supply (UPS) equipment maintaining constant voltage, using a pulse width modulation(PWM) voltage fed inverter, as power source disconnection, voltage variation and output current variation with load variation. This system is driven by being synchronized voltage fed inverter and AC source, and in the steady state of power source charge battery connected to dc side with solar cell using a photovoltaic (PV) that it was so called constant voltage charge. In addition, better output waveform was generated because of PWM method, and it was proved to test by experiment maintained constant output voltage regardless of AC source disconnection, load variation, and voltage variation of AC power source.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.1089-1090
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• 2006

This paper analyzes impedance convergence characteristics and harmonics of electric locomotives operation and fault condition. To simulate the various fault and operation condition, AT feeding system and various locomotives are modeled using PSCAD/EMTDC. Analysis shows that impedance are converged into protection area in the case of short fault between catenary and rail or catenary and feeder line but in the case of disconnection fault, impedance is rater bigger so protective relay can't detect the fault. Therefore more analysis of overload and high impedance fault caused disconnection fault is needed.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.417-420
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• 2003

In this paper, we have designed the ground faults detection and disconnection algorithm at normal rendition of AC 120V to 240V rating voltage. Ground faults in electrical network have the characteristics of low current, 60Hz frequency to 2kHz frequency. The load rendition are no load and 20A load. The controller have the trip level are 6mA with ground faults. Conventional controller does not have the miswiring condition. The Controller algorithm using pic16c71 microprotessor.

• Journal of KIISE:Databases
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• v.30 no.6
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• pp.606-628
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• 2003

Recently, there have been many research efforts reported in the literature that focus on the cache consistency problems of mobile clients resulting from their frequent disconnections with a server in mobile environments. To cope with this problem, a number of methods based on the invalidation report scheme has been proposed. However, these proposed methods are sensitive to the disconnection time of mobile clients and independent of the frequency of data updates in the server. As a result, although the number of data updated in the server is small, the traditional methods can not guarantee the cache consistency of mobile clients if their disconnection time is over the time period the invalidation report is allowed to cover. In this paper, we propose an efficient cache consistency method called CCI(Cost-based Cache Invalidation) for mobile clients that take into account not only the disconnection time but also the frequencies of data updates in the server We also present an in-depth experimental analysis by comparing CCI method with BT(Broadcasting Time stamp) method based on Invalidation Report.

• Journal of KIISE:Information Networking
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• v.27 no.2
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• pp.149-159
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• 2000

In mobile computing environments, invalidation and propagation method based on broadcasting is used to transmit the information for cache maintenance of mobile hosts. Previous researches generally adopted invalidation method that easily adapts to the limited network bandwidth and the frequent disconnection. But the invalidation of frequently accessed data causes the contention on the wireless network with the increasing cache requests. Although the propagation method can reduce the cache requests, the high probability of broken message or loss of message is the main factor that degrades the system performance. To resolve these problems, we propose adaptive cache maintenance scheme that dynamically adjusts the broadcasting ratio of invalidation and propagation, according to the wireless network connection states. The proposed scheme broadcasts the propagation message in stable connection state, so it can reduce the cache requests and server response time. With the decreasing available network bandwidth by the frequent partial disconnection and disconnection, the proposed scheme dynamically increases the broadcasting ratio of the invalidation messages to minimize the broken message or the loss of message probability. Consequently, the proposed scheme resolves the problems which arise in the invalidation or propagation method in mobile computing environments.

• Korean Journal of Childcare and Education
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• v.11 no.5
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• pp.191-214
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• 2015

The purpose of this study was to investigate variables which have an influence on young children's peer interactions. The data of 966 4-year-old children and their parents and class teachers were extracted from the 5th Panel Study on Korean Children in 2012 by Korea Institute of Child Care and Education. The data were analyzed by means of ANOVA, Pearson's coefficient and multiple regression. The results were as follows: First, boys' play disruption and play disconnection were higher than girls', and girls' play interaction was higher than boys'. Second, sociability and activity of temperament, and teacher-child interaction were related to peer disruption. Third, teacher-child interaction and sociability of temperament significantly affected play interaction. Controlling parenting behavior of the mother was positively related to peer interaction in girls. Fourth, teacher-child interaction, sociability and emotionality of temperament significantly affected play disconnection. Social parenting behavior of the father was negatively related to play disconnection in boys. Lastly, teacher-child interaction was the clearest indicator for young children' peer interactions. These findings suggested a potential role of the teacher in young children's peer interactions.

• The Journal of Internal Korean Medicine
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• v.27 no.3
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• pp.762-769
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• 2006

A callosal disconnection syndrome results in the functional independence of each hemisphere caused by ACA infarction, head injury or callosal operation for epilepsy. Clinical features are characterized by left unilateral tactile anomia, left unilateral agraphia, left unilateral apraxia, difficulty in copying drawings, dyscalculia and alien hand syndrome. Taeumchowe-tang(太陰調胃湯) is used to treat Taeumin(太陰人) Wewansuhanpyohanbyung(胃脘受寒表寒病). A 47 year-old man, following callosal infarction, was detected on MRI with left agraphia, dyscalculia and alien hand syndrome, but no left ideomotor apraxia or left apraxia. He was treated with Taeumchowe-tang. Significant improvement of clinical symptoms was seen, so it is here reported.

• Science of Emotion and Sensibility
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• v.23 no.2
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• pp.89-102
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• 2020

Consumers purchase gifts for themselves and for others. This research examined whether one's preferred purchase type (material or experiential) would depend on the gift recipient (self or others). A total of 200 participants took part in online studies via Amazon Mechanical-Turk. Based on the construal-level theory, people will focus on concrete product attributes for psychologically close objects; however, for psychologically distant objects, people will concentrate on abstract product attributes. Study 1 demonstrated that participants preferred material over experiential purchases in self-gifting situations, while they preferred experiential compared to material gifts for others. In Study 2, it was found that individual differences in emotional disconnection moderated the effect of gift recipient on preferred gift type. Specifically, the differences in preferred gift type increased as one's emotional disconnection level increased. The results of this research have theoretical implications in terms of extending construal-level theory to gift-purchasing behaviors. Furthermore, this research has practical implications for marketers and advertisers. Limitations and possible future research directions were also discussed.