• Journal of Institute of Control, Robotics and Systems
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• v.17 no.12
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• pp.1248-1255
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• 2011

In daily life, another major role of human hand is a communicative function using hand gestures besides grasp function. Therefore, if amputees can express their intention by the prosthetic hand, they can much actively participate in social activities. Thus, this paper propose myoelectric multi-function prosthetic hand which can express 6 useful hand gestures such as Rock, Scissors, Paper, Indexing, Ok and Thumb-up. It was designed as under-actuated structure to minimize volume and weight of the prosthetic hand. Moreover, in order to effectively control various hand gestures by only two EMG sensors, we propose a control strategy that the signal type are expanded as "Strong" and "Light", and hand gestures are hierarchically classified for the intuitive control. Finally, we prove the validity of the developed prosthetic hand with the experiment.

• Journal of Advanced Marine Engineering and Technology
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• v.20 no.2
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• pp.75-75
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• 1996

The rapid expansion for the auto-industry and the worldwide trend toward non-asbestos friction materials for brake lining force our industry to transfer into non-asbestos ones from asbestos-based friction materials. Furthermore, it is imperative for the friction materials to have technological excellence and lower production cost to be competitive in the world market. There is no known theoretical procedures to formulate friction materials. It, rather, depends on the trial and error process. Thus, it is quite clear how important it is to accumulate the know-how on the formulation and manufacturing the friction material. This study concerns the practical ways of conceptualizing the formulation and optimizing the manufacturing process. This study focused on the development of formulation for non-asbestos friction material as well as deriving the physical properties of the trial product to prove its validity and applicability. Elaboration of the formula and optimizing scheme of the manufacturing process to get better quality are also sought. Physical properties were obtained by constant velocity test dynamotest, hardness test and strength test. Differential scanning calorimeter was also used to analyze the thermal reactions of organic constituents, microstructures, bond effects, and degree of mixture.

• Journal of Advanced Marine Engineering and Technology
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• v.20 no.2
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• pp.7-14
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• 1996

The rapid expansion for the auto-industry and the worldwide trend toward non-asbestos friction materials for brake lining force our industry to transfer into non-asbestos ones from asbestos-based friction materials. Furthermore, it is imperative for the friction materials to have technological excellence and lower production cost to be competitive in the world market. There is no known theoretical procedures to formulate friction materials. It, rather, depends on the trial and error process. Thus, it is quite clear how important it is to accumulate the know-how on the formulation and manufacturing the friction material. This study concerns the practical ways of conceptualizing the formulation and optimizing the manufacturing process. This study focused on the development of formulation for non-asbestos friction material as well as deriving the physical properties of the trial product to prove its validity and applicability. Elaboration of the formula and optimizing scheme of the manufacturing process to get better quality are also sought. Physical properties were obtained by constant velocity test dynamotest, hardness test and strength test. Differential scanning calorimeter was also used to analyze the thermal reactions of organic constituents, microstructures, bond effects, and degree of mixture.

• Korean Institute of Interior Design Journal
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• v.22 no.5
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• pp.162-170
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• 2013

Although vision has been considered as a top sensory organ in the Western culture until modern times, the significance of space experience that communicates with a body via complex perceptions has recently garnered attention. This study criticizes the limitations of a vision-centered space and has the goal of empirically examining the sensibility characteristics in a haptic space through post-structuralism views leading up to Gilles Deleuze's philosophical ideas. This study will explore the flow of senses from the philosophical and artistic standpoint and the sensibility characteristics in a haptic space by examining the theories on haptic perceptions in connection with a space. In order to test the existing theories and identify the differences in sensibilities depending on perceptual method, the sensibilities of participants were compared using SD method (Semantic Differential scale method) and a validity test was conducted using a statistical program SPSS. The research has revealed that the average sensitivity scale of complex haptic perception was higher than single perception that only relies on vision. In addition, there was a correlation between perceptual method based on various sensory organs and human sensitivities. This study is meaningful in that it can serve a foundation for empirical research on sensibility, since it has reexamined the relationship between space and participants and demonstrated and analyzed their sensitivities through an experiment.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.10
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• pp.1006-1013
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• 2011

In this paper, we propose an optimal posture control law for an unmanned bicycle by deriving linear bicycle model from fully nonlinear differential equations. We calculate each equilibrium point of a bicycle under any given turning radius and angular speed of rear wheel. There is only one equilibrium point when a bicycle goes straight, while there are a lot of equilibrium points in case of turning. We present an optimal equilibrium point which makes the leaning input minimum when a bicycle is turning. As human riders give rolling torque by moving center of gravity of a body, many previous studies use a movable mass to move center of gravity like humans do. Instead we propose a propeller as a new leaning input which generates rolling torque. The propeller thrust input makes bicycle model simpler and removes input magnitude constraint unlike a movable mass. The proposed controller can hold optimal equilibrium points using both steering input and leaning input. The simulation results on linear control for circular motion are demonstrated to show the validity of the proposed approach.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.20 no.1
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• pp.1-13
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• 2016

Objectives The aim of this study is to develop diagnostic and assessable questionnaires for cervical movement system impairment syndromes. Methods We reviewed the previous study and literature, and organized various checkable items for differential diagnosis of four different cervical movement system impairment syndromes. Next, we selected items which can be developed as questionnaire items. Finally, we conducted a face validity study with twelve Korean medical doctors and carried out survey research to evaluate the importance score of the items with three experts. Results We developed a diagnostic and assessable questionnaire as follows: 9 items for cervical extension syndrome; 5 items for cervical flexion syndrome; 9 items for cervical rotation syndrome. By conducting 2 rounds of survey research, we were able to bridge the differences in the importance score of each item. Conclusions A questionnaire for the diagnosis and assessment of movement system impairment syndromes was developed. This questionnaire holds promising applications for objective diagnosis and assessment of cervical movement system impairment syndromes. This tool may also be used for detecting the sub-health status of musculoskeletal systems.

• Steel and Composite Structures
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• v.23 no.6
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• pp.657-668
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• 2017

In the most of previous studies, researchers have restricted their own studies to consider the effect of single walled carbon nanotubes as a reinforcement on the vibrational behavior of structures. In the present work, free vibration characteristics of functionally graded annular plates reinforced by multi-walled carbon nanotubes resting on Pasternak foundation are presented. The response of the elastic medium is formulated by the Winkler/Pasternak model. Modified Halpin-Tsai equation was used to evaluate the Young's modulus of the multi-walled carbon nanotube/epoxy composite samples by the incorporation of an orientation as well as an exponential shape factor in the equation. The exponential shape factor modifies the Halpin-Tsai equation from expressing a straight line to a nonlinear one in the multi-walled carbon nanotubes wt% range considered. The 2-D generalized differential quadrature method as an efficient and accurate numerical tool is used to discretize the equations of motion and to implement the various boundary conditions. The effects of two-parameter elastic foundation modulus, geometrical and material parameters together with the boundary conditions on the frequency parameters of the plates are investigated. This study serves as a benchmark for assessing the validity of numerical methods or two-dimensional theories used to analysis of annular plates.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.1
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• pp.68-76
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• 2007

As an alternative approach to evaluate the unit heating load for apartment houses, we newly developed and proposed unit building method. The new method, which calculates the heating load of an apartment building as a whole, conceptually corresponds to integral analysis of building heat loss, while the existing unit apartment method to differential analysis. Four typical building models of Korean-style apartment house and two dynamic load calculation programs were selected to validate the present method under realistically imposed conditions. Eight sets of unit heating load calculated respectively by unit building and unit apartment methods showed excellent agreements regardless of building model and simulation program. It is expected that the unit building method can take the place of the unit apartment method due to fewer modeling assumptions as well as less computational efforts. Additional calculations to investigate the effects of various parameters on unit heating load yield good consistencies with known facts, and re-confirm the validity.

• Proceedings of the Korean Institute of Landscape Architecture Conference
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• 2007.10b
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• pp.89-93
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• 2007

In the Japanese garden, a unique planting design has been used to improve visual harmony with the surrounding landscape by planting plants around the objects that are not harmonious with surrounding landscape. In this study, physiopsychological effects of plants caused by a traditional planting skill used in Japanese garden was verified in terms of visual relaxation using eye movement recording and semantic differential method. A total of fourteen Japanese volunteers(seven male and seven female) who have normal vision(aged $21{\sim}28$) participated as subjects. Experiment was carried out in the sealed room of Chiba University in Japan. Four different types of scenery models were presented which were created by combination of the three landscape factors of the surrounding background, the object that disturbs visual harmony, and the trees planted for improving visual harmony with the surrounding landscape. In the results, significantly more gaze fixations were measured on the trees than on the object and higher values in positive feelings were recorded for the stimuli with proper planting combination. Our results indicated that proper tree planting can cause physiopsychological relaxation by improving visual harmony with the surrounding landscape and provided new evidence for supporting scientific validity of the traditional planting skills.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.52 no.2
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• pp.74-80
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• 2003

In this paper, a robust two-degree-of-freedom(TDF) the speed control system using $H_{\infty}$ optimization method and real genetic algorithm is proposed for the robust stability and the robust performance in dc servo motor system. This control system composed of feedback and feedforward controller. The feedback(FB) controller with $H_{\infty}$ optimization method is designed for real genetic algorithm that is model matching problem using mixed sensitivity function. The feedforward(FF) controller with $H_{\infty}$optimization method is minimized the error between transfer function of the optimal model and the overall transfer function. The proposed robust two-degree-of-freedom speed control system is simulated to the dc servo motor. By the simulation, feedback controller can obtain the robust stability property and feedforward controller can obtain the robust performance property under modelling error. The performance of the dc servo motor is analyzed by the experiment setting. The validity of the proposed method is verified through being compared with pid(proportional integrated differential)control system design method for the dc servo motor.