• Proceedings of the KSME Conference
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• 2001.11b
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• pp.388-393
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• 2001

An experimental study is conducted to investigate the interaction of vortices over a delta wing with leading edge extension(LEX) through the off-surface flow visualization and the 5-hole probe measurements of the wing wake region. Especially, the application of a new visualization technique is employed by ultrasonic humidifier water droplet and laser beam sheet. The results, both the off-surface visualization and the 5-hole probe, show that LEX tends to stabilize the vortices of the delta wing up to the high angle of attack even though the model is yawed. With increasing yaw, the windward leading edge vortex moves inward, and closer to the wing surface, while the leeward vortex moves outwards and away from the wing surface. The vortex interaction is promoted in the windward side, and is delayed in the leeward side.

• Korean Journal of Optics and Photonics
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• v.7 no.1
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• pp.9-16
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• 1996

We perform computer simulations of a lenticular autostereoscopic display system and obtain two one-dimensional intensity distributions seen by the left and right eyes of the observer, respectively. Our result shows that the lens period should be smaller than the LCD pixel period as the observer moves closer to the system. We obtain the values of the system parameters for which the intensity distributions are uniform across the lenticular lens array. We also obtain the system crosstalks which represent the right pixel image seen by the left eye and the left pixel image seen by the right eye. Our simulation also shows that the crosstalk increases as the observer moves away from the lenticular system.

• Journal of Korea Multimedia Society
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• v.20 no.4
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• pp.640-648
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• 2017

Sensors have limited resources in sensor networks, so efficient use of energy is important. In order to use the energy of the sensor node efficiently, researches applying mobile sink to the sensor network have been actively carried out. The sink node moves the sensor network, collects data from each sensor node, which spread the energy concentrated around the sink node, thereby extending the entire life cycle of the network. But, when the sink node moves, it requires a reset of the data transmission path, which causes a lot of control messages and delays. In this paper, we propose a CMS(Cluster-based Mobile Sink) method to support the movement of mobile sink in a cluster sensor environment. The proposed scheme minimizes an amount of control messages without resetting the routing paths of entire sensor networks by supporting the sink mobility path using the neighbor cluster list. And, it simplifies the routing path setup process by setting a single hop path between clusters without a gateway. The experiment results show that the proposed scheme has superior energy efficiency in processing and network structure, compared with existing clustering and mesh routing protocols.

• Proceedings of the KIPE Conference
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• 2003.07b
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• pp.677-680
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• 2003

The control of the SRM(Switched Reluctance Motor) is usually based on the non-linear inductance profiles with positions. So determination of optimal switching angle is very different. we present self-tuning control of SRM for maximum torque and efficiency with phase current and shaft position sensor During the sample time, micro-controller checks the number of pre-checked pulse. After micro-controller calculates between two data, it move forward or backward turn-off angle. When the turn-off angle is fixed optimal turn-off angle, turn-on angle moves forward or backward by a step using self-tuning control method. And then, optimal turn-off angle is searched once again. As such a repeating process, turn-on/off angle is moves automatically to obtain the maximum torque and efficiency. The experimental results are presented to validate the self-tuning algorithm.

• Journal of the Korean Regional Science Association
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• v.6 no.1
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• pp.39-55
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• 1990

The principal measure of housing demand is income and the preferences expressed by households through their respective indifference curves. In this context, housing essentially becomes a derived demand, i.e., the household consumes land and a location (or distance-in time and money costs), according to its relative preferences for space, accessibility, and all other nonhousing goods. This paper attempts to deal with both aspects of housing (apartment) demand and household mobility in the Seoul Metropolitan Areas. Housing services will be measured using hedonic regression technique. From observations on the market prices of dwelling units and on the underlying characteristics of housing, one can estimte the relationships between the two empirically. In predicting the probability of the future moves into new towns in the Seoul Metropolitan areas, the best predictors of the future moves into new best predictors are found to be the degree of satisfaction not only with the current residence as a whole, but with some of the major amenities, accessibility and child education. The reasons for moving into new towns are diverse depending on the households' current situation; the most frequently cited is "improvement of housing conditions," followed by "improvement of living environment," "asset improvement" and "home ownership". It appears that people move houses because of a dissatisfaction with their current housing status, relative their income or needs, or a desire to improve their housing and neighborhood amenities, or both. On the other hand, it is clear that the development of new towns in the Seoul Metropolitan Areas should be based on the analysis of housing demand and the pattern of household mobility in Seoul housing market.sehold mobility in Seoul housing market.

• International Journal of Highway Engineering
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• v.19 no.6
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• pp.175-182
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• 2017

PURPOSES : Road sectors contribute approximately 16 % of total GHG emission rates in South Korea. Engineers and experts expend significant efforts to identify countermeasures for the reduction of carbon emission. This study aims to determine how total carbon emission rates change depending on whether or not there is speed limit enforcement. METHODS : In this study, Lamm's travel speed profile theory is first adopted to select the hazard road, which sections are designated as speed limit enforcement. Second, Motor Vehicle Emission Simulator (MOVES) was used to simulate the carbon emission on the road. RESULTS : The total carbon emission rate under speed limit enforcement was 10,773 g higher than the condition without speed limit enforcement in the designated road. This might affect acceleration, which can lead to increased emissions. CONCLUSIONS : There would be no researches about proving the relationship how speed limit enforcement has an effect on carbon emission. The result of our study can provide valuable guidelines regarding road safety and eco-friendly roads.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.12
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• pp.4661-4676
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• 2014

In Wireless Mesh Networks (WMN), an authentication technique can be compromised due to the distributed network architecture, the broadcast nature of the wireless medium and dynamic network topology. Several vulnerabilities exist in different protocols for WMNs. Hence, in this paper, we propose trust based authentication and key establishment for secure routing in WMN. Initially, a trust model is designed based on Ant Colony Optimization (ACO) to exchange the trust information among the nodes. The routing table is utilized to select the destination nodes, for which the link information is updated and the route verification is performed. Based on the trust model, mutual authentication is applied. When a node moves from one operator to another for accessing the router, inter-authentication will be performed. When a node moves within the operator for accessing the router, then intra-authentication will be performed. During authentication, keys are established using identity based cryptography technique. By simulation results, we show that the proposed technique enhances the packet delivery ratio and resilience with reduced drop and overhead.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.199-209
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• 2009

The movement of the caisson used to construct a wharf front can affect functional performance of the port. Sequential movement of caissons at each stage of the construction is essential in the overall design as well as the stability of the port. It is common that back-analysis using the previous measurement is performed to predict the caisson movement, while there is no intensive study on sequential movement of the caissons according to the construction stage. In the study, we analyzed the pattern of the movement of caissons as a port is constructed. To simulate the construction of the port, the finite element method (FEM) is employed. The computed result shows that the caisson moves differently at each construction stage. When the caisson is being installed, the displacement of the caisson takes place mainly in vertical direction. In next stage of filling rocks behind the caisson, the top of the caisson move toward shore, while the bottom moves toward sea, thus rotating the caisson. The maximum rotation of the caisson takes place in the stage of filling rocks behind the caisson.

• Journal of Haehwa Medicine
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• v.10 no.1
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• pp.385-394
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• 2001

Tough study of movement of Tae-Geuk-Guan(太極拳), we understand Tae-Geuk-Guan(太極拳) & essential movement. Theory about creator of Tae-Geuk-Guan(太極拳) is indistinct. there are Jangsampung-theory(張三豊設), Wangjongak-theory(王宗岳設), Jinwangjung-theory(陳王廷設), Jinbok-theory(陳卜設). Tae-Geuk-Guan(太極拳) is military arts developed before Song empire(宋). Tae-Geuk-Guan(太極拳) has many branch.(Jin-sik陳式, Yang-sik楊式, Mu-sik武式 O-sik吳式, Son-sik孫式) Tae-Geuk-Guan'(太極拳) manual movement use fist(拳), palm(掌), hook shape(鉤) and its using form has many type like Bung, Yi, Jae, An, Chae, Yul, Ju, Go. Its gait has many type like Sang-bo(上步), Tae-bo(退步), Jin-bo(進步), Deng-gak, Bun-gak(分脚), Bak-gak(拍脚). Essential theory of Tae-Geuk-Guan(太極拳) is Yi-Sim-Hang-Gi(以心行氣) & Yi-Gi-Un-Sin(以氣運身). It means mind(心) moves qi(氣) and qi(氣) moves body(身).

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.6
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• pp.95-102
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• 2015

Generally, there is no sorting algorithm much faster than O(nlogn). The quicksort has a best performance O(nlogn) in best and average-case, and $O(n^2)$ in worst-case. This paper suggests virtual radix counting bucket sort such that counting the frequency of numbers in each radix digit, and moves the arbitrary number to proper virtual bucket in the array, and divides the array into radix digit numbers virtually. Also, this algorithm moves the data to proper location within an array for using the minimum auxiliary memory. This algorithm performs k-times such that the number of k digits in given data and the time complexity is O(n). Therefore, this algorithm has a O(kn) time complexity.