• Korean Journal of Health Education and Promotion
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• v.28 no.4
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• pp.1-14
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• 2011

Objectives: The aim of the present study is to elucidate the relationship of community capacity to health in a metropolitan area in Korea. To do so, a multi-level model to verify the contextual effects of community capacity is presented. Methods: The study materials are the "The 4th Seoul Citizens Health Indicators Surveys" on 404 dong in Seoul. The community capacity indicators were developed in two strata: individual-level indicators with community identity domain; and community-level indicators with participation in community organizations, number of non-profit organizations, degree of organizing of community-based organizations, and volunteer activities. Results: Higher unhealthy probability occurs among those with lower community capacity at the community level, lower individual income, and lower community satisfaction at the individual level. It contributed to explaining self-rated health status and showed that there were contextual effects of the community going beyond the compositional effects of the individual. Conclusions: In the process of building community capacity, a community autonomously finds pending issues and solves related problems, and in so doing, raises the social quality and establishes the conditions for health promotion. Thus, the significance of neighborhood needs to be discovered and created in a new way through the development of community capacity.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.10
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• pp.1655-1663
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• 2016

Recently the researches on Modular Multi-level Converter (MMC) are being highlighted because high quality and efficient power transmission are key issues in the High Voltage Direct Current (HVDC) transmission system. This paper proposes an improved pre-charging method for the sub-module capacitors in MMC that operates in Nearest Level Control (NLC) modulation. The proposed method does not require additional circuits or Pulse Width Modulation (PWM) techniques. The feasibility of proposed method was verified through computer simulations for a scaled 3-phase 10kVA MMC with 12 sub-modules per each arm. Hardware experiments with a scaled prototype were performed in the lab to confirm the simulation results.

• Journal of Korea Multimedia Society
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• v.10 no.12
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• pp.1632-1644
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• 2007

Wireless Mesh Networks aim to attain large connectivity with minimum performance degradation, as network size is increase. As such, scalability is one of the main characteristics of Wireless Mesh Networks that differentiates it from other wireless networks. This characteristic creates the need for bandwidth efficiency strategies to ensure that network performance does not degrade as the size of the network increase. Several researches have been done to realize mesh networks. However, the researches conducted were mostly focused on a per TCP/IP layer basis. Also, the studies on bandwidth efficiency and bandwidth improvement are usually dealt with as separate issues. This paper aims to simultaneously study bandwidth efficiency and improvement. Aside from optimizing the bandwidth given a fixed capacity, the capacity is also increased using results of physical layer studies. In this paper, the capacity is improved by using the concept of non-overlapping channels for wireless communication. A channel allocation scheme is conceptualized to choose the transmission channel that would optimize the network performance parameters with consideration of chosen Quality of Service (QoS) parameters. Network utility maximization is used to optimize the bandwidth after channel selection. Furthermore, a routing scheme is proposed using the results of the network utilization method and the channel allocation scheme to find the optimal path that would maximize the network gain.

• Wind and Structures
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• v.21 no.6
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• pp.625-639
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• 2015

Monopiles have been most widely used for supporting offshore wind turbines (OWTs) in shallow water areas. However, multi-member lattice-type structures such as jackets and tripods are also considered good alternatives to monopile foundations for relatively deep water areas with depth ranging from 25-50 m owing to their technical and economic feasibility. Moreover, jacket structures have been popular in the oil and gas industry for a long time. However, several unsolved technical issues still persist in the utilization of multi-member lattice-type supporting structures for OWTs; these problems include pile-soil-interaction (PSI) effects, realization of dynamically stable designs to avoid resonances, and quick and safe installation in remote areas. In this study, the effects of PSI on the dynamic properties of bottom-fixed OWTs, including monopile-, tripod- and jacket-supported OWTs, were investigated intensively. The tower and substructure were modeled using conventional beam elements with added mass, and pile foundations were modeled with beam and nonlinear spring elements. The effects of PSI on the dynamic properties of the structure were evaluated using Monte Carlo simulation considering the load amplitude, scouring depth, and the uncertainties in soil properties.

• Clinical and Experimental Pediatrics
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• v.54 no.7
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• pp.277-281
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• 2011

Failure to thrive (FTT) is a term generally used to describe an infant or child whose current weight or rate of weight gains is significantly below that expected of similar children of the same age, sex and ethnicity. It usually describes infants in whom linear growth and head circumference are either not affected, or are affected to a lesser degree than weight. FTT is a common problem, usually recognized within the first 1-2 years of life, but may present at any time in childhood. Most cases of failure to thrive involve inadequate caloric intake caused by behavioral or psychosocial issues. The most important part of the outpatient evaluation is obtaining an accurate account of a child's eating habits and caloric intake. Routine laboratory testing rarely identifies a cause and is not generally recommended. FTT, its evaluation, and its therapeutic interventions are best approached by a multi-disciplinary team includes a nutritionist, a physical therapist, a psychologist and a gastroenterologist. Long term sequelae involving all areas of growth, behavior and development may be seen in children suffering from FTT. Early detection and early intervention by a multidisciplinary team will minimize its long term disadvantage. Appropriate nutritional counseling and anticipatory guidance at each well child visit may help prevent some cause of FTT.

• Journal of the military operations research society of Korea
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• v.31 no.1
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• pp.42-57
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• 2005

Korea DM&S(Defence Modeling & Simulation) development plan includes construction of a distributed simulation model which enables us to construct, operate, integrate and connect war game simulations. US DoD and IEEE set the HLA/RTI as the standard of distributed simulation model. HLA/RTI models each simulator as a Federate and group of them as a Federation. Simulation with the model shows interoperability and finally executes a war game simulation. Because of different resolutions and features, it is not satisfied 'interoperability' and 'reusability' of simulation perfectly MRM (Multi Resolution Modeling) has been introduced, and many developed countries including the United States have studied the technology to simulate the model with different resolutions. This thesis proposes the need for introduction of MRM and analyzes both technical and operational validity when we apply MRM model to army war game simulations. For these purposes, we 1) find MRM main issues with the study about MRM basic concepts and case studies of MRM's applications, 2) present the need of MRM and its relation with DM&S development plan, and 3) analyze its technical and operational validity when we apply MRM to an example, CHANG-JO21 and JEON-TOO21.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.11
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• pp.1092-1097
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• 2014

Unmanned flying robots have been used recently in many difficult situations. One of the major issues in this area is the problem of how long these unmanned flying robots can perform a given task successfully. For this, the development of a light body and high-efficiency power supply has been executed widely, but we do not as yet have the complete solution. In this paper, we propose a form of Multi-Copter X8, which can transform into other types to further improve these problems. The proposed robot has a 3-type modification capability, which can produce a more enhanced energy saving effect by reducing power consumption.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.338-350
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• 2010

As existing materials for ground reinforcement, chemical grout material using cementitous materials and waterglass was used. But many problems in terms of ground reinforcement effects were implicated. In this study, for development and applicability verification of new materials, viscosity, fluidity, permeability, Self-Leveling, keeping of drilled hole, antiwashout underwater, resistance of water (groundwater dilution and minimize material eluting) and the early strength and long-term strength characteristics of developed materials was confirmed, and material standards, and establishing construction standards for the various model tests were conducted. As a result, high viscosity, flowability, permeability and keeping of drilled hole characteristics are excellent, in addition to the early strength properties, dilution does nat occur to groundwater, including groundwater is available for dealing with environmental issues. Application of basic and reinforcement method by Filler function in addition to structure can also or development of a new concept can be expected. In addition, middle and large-diameter drilled shaft, micropile, ground anchors, soil-nailing, steel pipes multi-grouting reinforcement for cement injection process could be used enough to even be considered.

• ETRI Journal
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• v.39 no.3
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• pp.326-335
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• 2017

In the uplink transmission of massive (or large-scale) multi-input multi-output (MIMO) systems, large dimensional signal detection and its hardware design are challenging issues owing to the high computational complexity. In this paper, we propose low-complexity hardware architectures of Richardson iterative method-based massive MIMO detectors. We present two types of massive MIMO detectors, directly mapped (type1) and reformulated (type2) Richardson iterative methods. In the proposed Richardson method (type2), the matrix-by-matrix multiplications are reformulated to matrix-vector multiplications, thus reducing the computational complexity from $O(U^2)$ to O(U). Both massive MIMO detectors are implemented using a 65 nm CMOS process and compared in terms of detection performance under different channel conditions (high-mobility and flat fading channels). The hardware implementation results confirm that the proposed type1 Richardson method-based detector demonstrates up to 50% power savings over the proposed type2 detector under a flat fading channel. The type2 detector indicates a 37% power savings compared to the type1 under a high-mobility channel.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.10
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• pp.4976-4994
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• 2018

The diffusion-based salient object detection methods have shown excellent detection results and more efficient computation in recent years. However, the current diffusion-based salient object detection methods still have disadvantage of detecting the object appearing at the image boundaries and different scales. To address the above mentioned issues, this paper proposes a multi-scale diffusion-based salient object detection algorithm with background and objectness seeds. In specific, the image is firstly over-segmented at several scales. Secondly, the background and objectness saliency of each superpixel is then calculated and fused in each scale. Thirdly, manifold ranking method is chosen to propagate the Bayessian fusion of background and objectness saliency to the whole image. Finally, the pixel-level saliency map is constructed by weighted summation of saliency values under different scales. We evaluate our salient object detection algorithm with other 24 state-of-the-art methods on four public benchmark datasets, i.e., ASD, SED1, SED2 and SOD. The results show that the proposed method performs favorably against 24 state-of-the-art salient object detection approaches in term of popular measures of PR curve and F-measure. And the visual comparison results also show that our method highlights the salient objects more effectively.