• ETRI Journal
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• v.27 no.3
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• pp.243-249
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• 2005

A mobile antenna for multimedia communications with Ku-band geostationary satellite KOREASAT-3 and JSAT-2A is presented. The forward link of the satellite communication is 11.7 to 12.75 GHz, and the return link is 14.0 to 14.5 GHz. The mobile antenna is designed to be a stair structure using 24 active phased array elements in order to provide a low profile, and to be at a non-periodic array distance using the genetic algorithm. Also, the designed antenna uses the double beam forming method for stable satellite tracking. The fabricated mobile antenna is examined using various experiments to confirm its capability for practical application. From the measured results, the fabricated mobile antenna system is confirmed to have a good performance.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.2
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• pp.373-381
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• 2009

In this paper, a humanoid robot is simulated and implemented to walk up a staircase using the blending polynomial and genetic algorithm. Using recently developed kinematics for a biped robot, four schemes for walking up a staircase are newly proposed and simulated separately. For the two schemes of landing a swaying leg on the upper stair, the joint trajectories of seven motors are particularly optimized to generate an energy-minimal motion with the guarantee of walking stability. The proposed scheme of walking upstair is validated by an experiment with a small humanoid robot.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.19-20
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• 2015

Building exterior wall's energy loss is very high rate comparing to all part of a buildings. And it account for upper 40% of cooling and heating load. So many studies conducted improving insulation performance of building's exterior, appeared about sandwich insulation wall which could be gaining merit of traditional insulation method those are exterior insulation and interior insulation. In this study, we inform structural performance of sandwich insulation wall for RC wall. For this, first, we define each wall's role and design sandwich insulation wall. At last, analyze structural performance of sandwich insulation wall. This study can contribute to apply it safely where side wall which toilet, stair area, etc.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.2 s.54
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• pp.137-144
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• 2009

This paper provides the results from evaluating the stiffness of Hi-Form joint by an experiment and the system identification method using the dynamic modal data, and the reasonable modeling method of Hi-Form joint which is proposed for improved stair construction recently. Based on the crack pattern and load-displacement relationship and the damage distribution, it can be judged that Hi-Form joint can't fully transfer the forces between the elements linked, and we propose that the joint is modeled as a element which have a stiffness with 50% decrease.

• Earthquakes and Structures
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• v.16 no.4
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• pp.437-453
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• 2019

This study investigates a new optimal placement method for viscous dampers between structures in order to prevent pounding of adjacent structures with different dynamic characteristics under earthquake effects. A relative displacement spectrum is developed in two single degree of freedom system to reveal the critical period ratios for the most risky scenario of collision using El Centro earthquake record (NS). Three different types of viscous damper design, which are classical, stair and X-diagonal model, are considered to prevent pounding on two adjacent building models. The objective function is minimized under the upper and lower limits of the damping coefficient of the damper and a target modal damping ratio. A new algorithm including time history analyses and numerical optimization methods is proposed to find the optimal dampers placement. The proposed design method is tested on two 12-storey adjacent building models. The effects of the type of damper placement on structural models, the critical period ratios of adjacent structures, the permissible relative displacement limit, the mode behavior and the upper limit of damper are investigated in detail. The results of the analyzes show that the proposed method can be used as an effective means of finding the optimum amount and location of the dampers and eliminating the risk of pounding.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.3
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• pp.181-189
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• 2015

Powered prosthesis is used to assist walking of people with an amputated lower limb and/or weak leg strength. The accurate gait phase classification is indispensable in smooth movement control of the powered prosthesis. In previous gait phase classification using physical sensors, there is limitation that powered prosthesis should be simulated as same as the speed of training process. Therefore, we propose EMG signal based gait phase recognition method to classify stairs ascending and stairs descending into four steps without using physical sensors, respectively. RMS, VAR, MAV, SSC, ZC, WAMP features are extracted from EMG signal data and LDA(Linear Discriminant Analysis) classifier is used. In the training process, the AHRS sensor produces various ranges of walking steps according to the change of knee angles. The experimental results show that the average accuracies of the proposed method are about 85.6% in stairs ascending and 69.5% in stairs descending whereas those of preliminary studies are about 58.5% in stairs ascending and 35.3% in stairs descending. In addition, we can analyze the average recognition ratio of each gait step with respect to the individual muscle.

• Journal of architectural history
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• v.16 no.2
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• pp.99-118
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• 2007

Kyedan(戒壇) is an altar to perform a rite of Buddhist Initiation which gives Precept to a Buddhist monk. Sometimes it is called the Place of Precept and Mandala by Sanskrit. In this study, the Sutra of the Tang(唐) Dosun(道宣) regarding First Kyedan of Jetavana-anathapindasyarama(祇園精舍), which was the first temple such as, Kyedandokyung(戒壇圖經), Kiwonsadokyung(祇洹寺圖經), Sabunyul(四分律) were analyzed to find out original form and layout. Ultimately, the study was intended to examine the spatial formation-principle by comparing with Kyedan Temple. The results of this study could be summarized as below. First. Except for Kyedan in Bakryensa, the height of lower stone plate of Buddhist Bell-Shaped Stupa of Korean Kyedan is higher than three storied Kyedan that described in Kyedandokyung. Second. Buddhist Bell-Shaped Stupa above Kyedan was presumed that embodied image of Bell Pedestal and symbolism of overturned-bowl were combined together, when Kyedandokyung and Kiwonsadokyung were referred. It could be examined by the existence of stone lantern. Third. In Korea, the rite of Buddhist initiation that gives Precept in Kyedan has been considered impossible. However, when the rite was conducted, there was a possibility to establish wood stair. It is because that the Buddhist Stupa of Silleuuksa(神勒寺) and Woljeongsa(月精寺), which reflected the image of Kyedan had stone stair. Fourth, The method to build Kyedan of Dosun divided into Large Region and Small Region was applied to the method to construct Stone terrace behind Jeongmyeolbogung(寂滅寶宮) like Tongdosa(通度寺) and complete Kyedan on the stone terrace. In other words, Jeongmyeolbogung became Kyedanwon(戒壇院) and Kyedan, itself became Small Region. The area of Stone terrace became Large Region and naturally, they constituted an Institution. Fifth, Korean Kyedan which is consist of Jeongmyeonlbogung and Kyedan is a Korean original composition principles of Kyedangaram(戒壇伽藍) that can satiate all the functions of Kyedan as a religious subject and the place of the rite of Buddhist initiation, as it had complex of Outdoor Kyedan, which was suggested by the sutra of Dosun and Institution of Kyedan.

• The Journal of Korean Physical Therapy
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• v.17 no.1
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• pp.108-122
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• 2005

The gait training strategy in very important things for central nervous system(CNS) injury patients. There are many method and strategy for regaining of the gait who had CNS injury. A human being has central pattern generator(CPG) is spinal CPG for locomotion. It is a neural network which make the cyclical patterns and rhythmical activities for walking. Sensory input from loading and hip position is essential for CPG stimulation that makes the central neural rhythm and pattern generating structure. From sensory input, the proprioceptive information facilitate proximal muscles that controlled in voluntarily from cortical level and visual and / or acoustical information facilitate distal muscles that controlled voluntarily from subcortical level. Gait training method can classify that is functional level and structural level. Functional level includ level surface gait, going up and down the stair. It is important to facilitate a guide tempo in order to activate the central pattern generators. During the functional test or functional activities, can point out the poor period in gait that have to be facilitate in structural level. There are many access methods with patient position and potentiality. The methods are using of rhythmic initiation, replication and combination of isotonic with standing position. Clinically using it on weight transfer onto the stance leg, loading response, loading response and pre-swing, terminal stance, up and downwards stairs.

• Fire Science and Engineering
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• v.15 no.1
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• pp.93-99
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• 2001

This study aims to improve the Evacuation Performance o( the I)inc()unto-store in underground that is rapidly new shopping store in Korea. In this paper, The architectural properties of the floor plan and section was reviewed with egress focus, occupant load density of the Discount-store was surveyed and the procedure and method of performance based egress design for this occupancy was analysed with SIMULEX model and calculation method. As a result of modeling, more longer available safe egress time (ASET) is expected than required safe egress time (RSET)in underground discount-store. In order to improve the Evacuation Performance for this type occupancy, egress capacity including escape stair, aisle width, escape door is calculated with based on occupant load density and review of shopping cart's structure and size and maximum escape capacity of the cash counter.

• Journal of the Korea Society of Computer and Information
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• v.22 no.12
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• pp.69-77
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• 2017

This paper represents a novel framework for multi-scale image fusion. Multi-scale Kalman Smoothing (MKS) algorithm with quad-tree structure can provide a powerful multi-resolution image fusion scheme by employing Markov property. In general, such approach provides outstanding image fusion performance in terms of accuracy and efficiency, however, quad-tree based method is often limited to be applied in certain applications due to its stair-like covariance structure, resulting in unrealistic blocky artifacts at the fusion result where finest scale data are void or missed. To mitigate this structural artifact, in this paper, a new scheme of multi-scale fusion framework is proposed. By employing Super Resolution (SR) technique on MKS algorithm, fine resolved measurement is generated and blended through the tree structure such that missed detail information at data missing region in fine scale image is properly inferred and the blocky artifact can be successfully suppressed at fusion result. Simulation results show that the proposed method provides significantly improved fusion results in the senses of both Root Mean Square Error (RMSE) performance and visual improvement over conventional MKS algorithm.