• Journal of the Korean Society for Precision Engineering
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• v.23 no.6 s.183
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• pp.119-127
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• 2006

A non-destructive time domain approach to examine structural damage using parameterized partial differential equations and Galerkin approximation techniques is presented. The time domain analysis for damage detection is independent of modal parameters and analytical models unlike frequency domain methods which generally rely on analytical models. The time history of the vibration response of the structure was used to identify the presence of damage. Damage in a structure causes changes in the physical coefficients of mass density, elastic modulus and damping coefficients. This is a part of our ongoing effort on the general problem of modeling and parameter estimation for internal damping mechanisms in a composite beam. Namely, in detecting damage through time-domain or frequency-domain data from smart sensors, the common damages are changed in modal properties such as natural frequencies, mode shapes, and mode shape curvature. This paper examines the use of beam-like structures with piezoceramic sensors and actuators to perform identification of those physical parameters, and detect the damage. Experimental results are presented from tests on cantilevered composite beams damaged at different locations and different dimensions. It is demonstrated that the method can sense the presence of damage and obtain the position of a damage.

• The KIPS Transactions:PartC
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• v.13C no.5 s.108
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• pp.595-600
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• 2006

Nowadays, low-cost radio frequency identification (RFID) technique, is recognizable without the physical contact between the reader and the tag, has been attracting more and more interests from both industry and academic institutes. however, it causes the serious privacy infringement such as excessive information exposure and user's location information tracking due to the wireless characteristics. The security problem of read only tag can be only solved by physical method. In this paper, we propose a low-cost authentication protocol which can be adopted for read-only RFID tag using XOR and Partial ID. The proposed protocol is secure against reply attacking, eavesdropping and spoofing attacking so that avoiding the location privacy exposure

• Journal of the Korean Institute of Landscape Architecture
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• v.19 no.1
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• pp.31-43
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• 1991

In considering the relationship between natural beauty and the human frame of mind, or the interconnections between the Landscape and the point of view, we are concerned primaily with the external factors. Historically, certain physical features tended to cause shifts in human attitudes toward landscapes; We concentrate on this phenomenon of changeful scenery rather than on what psychological factors caused certain landscapes to be regarded as remarkable or unique. In a similar fashion we must ask ourselves what the basic elements in landscape are and attempt to ascertain their visual and spatial characteristics before we attempt to desingn environments that are fundamentally, physical in character. Futhermore, the experience of meanings, a part of literatual association process, appeared through the intension of nature study looking for the best landscape phenomena out of simple naturelooking. Of course, as the variable degree of landscapes changes, the dualistic relationship between humans and objects shows the different experience of meanings as the time changes even in landscapes which possess variable factors in same season. The study is conducted by defining the nature of recognizing and appreciating the logical structure of the concept "Landscape" after analysis of meaning context appeared in 'Kyung' which is consists of time, space and elements in landscape.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.4
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• pp.433-440
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• 2012

Various studies to improve the physical abilities of the human have been steadily continued from the past to the present. Only recently such technology has been realized, and those are expected to replace or complement human beings in large part. In this paper, the current status of developed wearable robots is investigated and studies were conducted in order to apply the types of robots in industry spot. In order to apply wearable exoskeleton robot to industry which enhances human physical capability, driving range of the robot's degrees of freedom were selected by analyzing working motion, and augmentative exoskeleton structure design process is presented by analyzing require torque and power during selected working motion. At the end of this paper, the designed mock-up is introduced to validate the feasibility of designed robot.

• Journal of Conservation Science
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• v.36 no.1
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• pp.60-72
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• 2020

The Inscribed stones of Hanyangdoseong has been weathered for a long time because of external environment and living organisms. To establish a long-term conservation-management strategy for the inscription stones, the material characteristics of the inscription stones of Naksan Mountain Area were identified, and its deterioration state was diagnosed. Consequently, it was confirmed that the Inscription stones of Naksan Mountain Area mainly comprised coarse-to medium-grained pinkish granite and biotite granite, and, in part, comprised reddish granite, quartz porphyry, and aplite. Presently, the Inscription stones of Naksan Mountain Area, Hanyangdoseong, is undergoing a considerable decrease in physical properties because of physical, chemical, and biological weathering. Moreover, it has been confirmed that the type of damage, such as blistering, soiling, and dicolouration, on the surface shows a significantly high deterioration rate, and that conservation treatment might be required in future. In addition, because the possibility of damage recurrence is high even after the treatment, the conservation state must be regularly monitored.

• Journal of the Korea Furniture Society
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• v.27 no.4
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• pp.343-351
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• 2016

This study was jointly conducted by the department of nursing science in a college of natural sciences and the furniture design department in the art and physical education to research the critical factors for the furniture development for the Elderly in consideration of the surging number of senior citizens not only in Korea but also globally. On the basis of the Elderly's physical and mental characteristics investigated by the department of nursing science, the furniture design guideline for the Elderly was presented. The following points should be considered at designing the furniture for the Elderly. First, multiple functions like chair with removable toilet bowl and part lighting in bed are advantageous. Second, the dimension of furniture such as chair, bed and sofa should be ergonomically thought in terms of structure for the Elderly's convenience. Third, the bright and vivid color of furniture should be chosen from the aspect of the design, while the different kinds of blue should be avoided. Small patterns and high glossy are not recommendable, but various kinds of feelings in different shapes are suggested. Forth, the material should contribute to the fracture prevention and for that sponge, fabric and leather smoothing the surface of furniture are recommendable as the finishing treatment in a wide variety of colors.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2007.05a
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• pp.222-226
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• 2007

Buildings form interior space when part of an external environment is limited by a physical surface. And, the interior space forms an appearance of building when space-defining elements, such as floor, wall, and roof. An appearance or a form of building has a lot of meanings depending on the physical and psychological conditions, as well as symbolism. Especially, the prevailing meaning of form in the modern age was, "Form follows function," was quite different from the meaning of form in the architectural era of Louis I. Kahn, who asserted "Form always supercedes function," when functional modernism was still existed even after some 50 years later. Existing studies on Louis I. Kahn usually analyzed his architectural terminology and philosophical concepts of Centrality, Light, Order, Form, and Design; or they were focused on an overall plane and the principle of composition. The purposes of this study are: (1) to investigate how the formal composition characteristics of building are expressed on skylights; and (2) to demonstrate that the formal composition characteristics of skylights plays an important role in constructing a whole structure of building in relation with other architectural elements.

• Journal of Korean Institute of Industrial Engineers
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• v.41 no.1
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• pp.74-78
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• 2015

A bus seat is required to be ergonomically designed in terms of its shape and physical properties to increase seating comfort. The present study is intended to develop a systematic bus seat evaluation protocol based on seating comfort. A total of 48 participants evaluated 12 parts (seat belt, recliner, armrest, headrest, upper-back support, lumbar support, seatback bolster, seatback overall, hip support, thigh support, seatpan bolster, and seatpan overall) of 12 bus seats with 17 subjective comfort measures (e.g., convenience of control, suitability of size, and overall comfort). Lastly, ergonomic features of shape and physical properties of each seat part were identified based on the subject evaluation analysis results. The developed bus seat evaluation protocol can be applied to evaluate various types of seats.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.3 no.1
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• pp.88-101
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• 2004

The Third Generation (3G) cellular mobile communication systems aim at providing higher data rates, improved quality of service, support for multimedia applications and global roaming. Cdma2000 and Universal Mobile Telecommunication System (UMTS) have emerged as two leading 3G standards in USA and European countries, respectively. Both the standards are capable of delivering high bandwidth data, voice and multimedia services to users of mobile equipment, but are not directly interoperableand are not available across different geographic areas, due to which global roaming is not possible in true sense of using single mobile equipment. However, both UMTS and cdma2000 are based on wideband code division multiple access (WCDMA) as the access method. Due to this, there exist some inherent commonalities between them. In this paper we will try to exploit the commonalities between the two standards in order to design an ASIC, which can provide dual standard capability. This paper discusses the physical layer aspects of the two standards and proposes an approach to design an ASIC which can be mapped to baseband processing part of the physical layer and is capable of delivering for either of the two aforementioned standards.

• The KIPS Transactions:PartB
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• v.9B no.1
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• pp.23-28
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• 2002

A fundamental problem in building an intelligent agent is that an agent does not understand the meaning of its perception or its action. One reason that an agent cannot understand the world is partially caused by a syntactic approach that converts a semantic feature into a simple string. To solve this problem, Cohen introduces a semantic approach that an agent autonomously learns a meaningful representation of physical schemas, on which some advanced conceptual structures are built, from physically interacting with environment using its own sensors and effectors. However, Cohen does not deal with a meta level of conceptual primitive that makes recognizing a schema possible. We propose that negation is a meta schema that enables an agent to recognize a physical schema. We prove some semantic aspects of negation.