• Proceedings of the KWS Conference
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• 2002.10a
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• pp.181-186
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• 2002

Laser welding application for car body manufacturing has many advantages in the stiffness and the lightness of vehicle, the productivity of assembly line, and the degree of freedom in design. This presentation will express the innovation of car body manufacturing including parameter optimization, process modeling, and system integration. In this application the investment for systems was cut down dramatically by real time switching over the laser path between two welding stations. Points of technical discussion are as follows: optimization of parameters such as laser power, robot speed and trajectory, compact and useful design of jig & fixture to assure welding quality for 3 sheet-layer zinc-coated steel, system integration between 4kW Nd:YAG laser device and the other systems, on-line real time welding quality monitoring system, perfect safety standards for high power laser, minimization of consumption costs such as arc lamp, protective glass for optic, etc. Laser welding has found a place on Hyundai's production plant in conjunction with the startup of mass production of new sports car, and this production system is the result of a collaboration of its engineers. Outer side sheets are joined to inner side sheets by 122 stitch welds totally. And the length is about 2.4meter.

• Journal of the Korean Home Economics Association
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• v.42 no.8
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• pp.49-64
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• 2004

The purpose of this study was to provide useful information which would help web-site planning and design, product composition, and service of internet shopping malls. The sample consisted of 693 university students who had visited(Ed- in this case 'visit' means to enter an internet site; note also that the past perfect tense already conveys the meaning of 'experience') internet fashion shopping malls or purchased clothing through internet. Data were analyzed by factor analysis, frequency, t-test, and ANOVA(LSD) using SPSSWIN. The results were as follows： 1) The evaluative criteria of internet fashion shopping malls could be categorized by 4 factors： product presentation method, design, product information, sales promotion ＆ additional service; the first of which was found to be the most important. These criteria showed significant differences according to the period and time of access. Furthermore, the degree of consideration for these criteria was high, whereas the degree of satisfaction was low. 2) The evaluative criteria of clothing could be categorized by 6 factors： general characteristics of products, wearing comfort ＆ ease of management, popularity ＆ status symbolism, service, aesthetics, and textiles materials; the first of which was found to be the most important. These criteria were significantly different according to the periods, time, and purposes of access, and purchase experiences.

• 한국IT서비스학회:학술대회논문집
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• 2008.11a
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• pp.157-160
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• 2008

The recent successes of systems like Google, Wikipedia and InnoCentive suggest that the time is now ripe for more such systems. Thus, we want to explore these systems and exploit them from a viewpoint of social psychology prior to technological progress. First of all, we examine the difference between 'wisdom of crowds' and 'crowd psychology'. There are two classes, which are for senior management major students. Conditions of two are same, except a class time. Forty five students in one class are tested for this experiment. They form a group with five people and are divided into 9 groups. In a case of a morning class, peer-to-peer evaluations are given to individuals in a class when a group presentation for a final project is given. On the other hand, in a case of afternoon class, peer-to-peer evaluations are given to each group in a class. The result is quite fruitful. The first is that an expert's evaluation for a project agrees with students, who are beginners in this field in the degree of more than 95%. However, in the case of afternoon class, students' group evaluation turns out to agree with an expert's one less than 53%. Morning class experiment result proves the truth of collective intelligence again. It tunrs out independent and confidential opinions are more cost effective and give right answers to questions than group opinions.

• Proceedings of the IEEK Conference
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• 2001.06e
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• pp.93-96
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• 2001

Tactile display devices use an array of pins mounted in the form of a matrix to present three-dimensional shapes to the user by raising and lowering. With a denser matrix of mounted pins, it can be expected that shape identification will be become easier and the time required for identification will also become shorter, but that problems of difficulty in fabrication will arise. It is necessary to consider such trade-offs in the development of such devices. This study conducted experiments to study the effect of pin pitch on shape identification as Part of the fundamental investigation of this subject. The experiment used three tactile display devices with pin pitches of In, 2mm and 3mm for geometrical shape identification, with response time and rate of misidentification taken as the performance data. Surfaces, edgs and vertices of three-dimensional shapes were used as the shape primitives for displayed shapes and several of each type were selected for presentation. The results obtained revealed that performance has different relationships to pin pitch with different shape primitives.

• Journal of Digital Contents Society
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• v.10 no.2
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• pp.319-326
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• 2009

In this paper, we present an algorithm which recognize hand shape in real time using only image without adhering separate sensor. Hand recognizes using edge orientation histogram, which comes under a constant quantity of 2D appearances because hand shape is intricate. This method suit hand pose recognition in real time because it extracts hand space accurately, has little computation quantity, and is less sensitive to lighting change using color information in complicated background. Method which reduces recognition error using principal component analysis(PCA) method to can recognize through hand shape presentation direction change is explained. A case that hand shape changes by turning 3D also by using this method is possible to recognize. Human interface system manufacture technique, which controls a home electric appliance or game using, suggested method at experience could be applied.

• The Bulletin of The Korean Astronomical Society
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• v.37 no.2
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• pp.78.1-78.1
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• 2012

We have studied the physical properties of X-ray point sources in galaxy clusters using ~600 Chandra archival observations. The goal of this study is to investigate the density environmental effects on the physical properties of X-ray point sources by comparing the properties of X-ray point sources in galaxy clusters to those in typical blank fields. In this presentation, we show the nature of X-ray point sources which are expected to be related with galaxy clusters with different core properties. Using ~60 galaxy clusters observed with Chandra, we investigate the physical properties of X-ray point sources in cool-core and non-cool-core clusters. The cool-core clusters are known to have short central cooling time, and are characterized by low central entropy, systematic central temperature drops, and a brightest cluster galaxy at the X-ray peak. While the non-cool-core clusters have longer central cooling time, and are characterized by large central entropies and flat or centrally rising temperature profile. We show that how central core properties of galaxy clusters affect on the physical properties of X-ray point sources.

• Steel and Composite Structures
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• v.3 no.3
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• pp.153-168
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• 2003

This paper discusses the results and observations from a large-scale fire test conducted on a slim floor system, comprising asymmetric beams, rectangular hollow section beams and a composite floor slab. The structure was subjected to a fire where the fire load (combustible material) was higher that that found in typical office buildings and the ventilation area was artificially controlled during the test. Although the fire behaviour was not realistic it was designed to follow as closely as possible the time-temperature response used in standard fire tests, which are used to assess individual structural members and forms the bases of current fire design methods. The presented test results are limited, due to the malfunction of the instrumentation measuring the atmosphere and member temperatures. The lack of test data hinders the presentation of definitive conclusions. However, the available data, together with observations from the test, provides for the first time a useful insight into the behaviour of the slim floor system in its entirety. Analysis of the test results show that the behaviour of the beam-to-column connections had a significant impact on the overall structural response of the system, particularly when the end-plate of one of the connections fractured, during the fire.

• 한국균학회소식:학술대회논문집
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• 2016.05a
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• pp.35-35
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• 2016

A mycotoxin is a toxic secondary metabolite produced by organisms of the fungus kingdom, commonly known as molds and has been widely contaminated in agricultural products such as grains and cereals. Many methods including high performance liquid chromatography (HPLC) and gas chromatography (GC) have already been proposed and reviewed for mycotoxins. These methods are either expensive or time-consuming due to the complication of sample preparation and pre-concentration before determination. In addition, both methods are unsuitable for the routine screening of large sample numbers. A biosensor is a fictive analytical device that combines a biological component with a physicochemical detector for the detection of an analyte. Biosensors represent a rapidly expanding field, at the present time, with an estimated 60% annual growth rate; the major impetus coming from the health-care industry but with some pressure from other areas, such as food safety and environmental monitoring. Antibodies and aptamers are bioreceptors which have been used in the development of biosensors. There are many kinds of antibodies and aptamers specific to mycotoxin, and antibody (or aptamer)-based biosensors have been successfully developed for the detection of mycotoxin. The biosensors permit the rapid, sensitive, simple, and on-site detection of a range of mycotoxins and can be an alternative method to traditional methods such as HPLC and GC. This presentation provides the development trends of biosensors to mycotoxins and their application to food and agricultural products.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.42
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• pp.2.1-2.6
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• 2020

Background: Facial palsy treatment comprises static and dynamic techniques. Among dynamic techniques, local temporalis transposition represents a reliable solution to achieve facial reanimation. The present study describes a modification of the temporalis tendon transfer using a cryopreserved fascia allograft. Case presentation: Between March 2015 and September 2018, seven patients with facial palsy underwent facial reanimation with temporalis tendon transfer and fascia lata allograft. Patients with long-term palsy were considered, and both physical and social functions were evaluated. The mean follow-up time was 21.5 months. No immediate complications were observed. Patients reported improvement in facial symmetry both in static and dynamic. Improvement was noticed also in articulation, eating, drinking, and saliva control. The Facial Disability Index revealed an improvement both in physical function subscale and in the social/well-being function subscale. Conclusions: This modified orthodromic technique allows to reduce the operative time and the risk of complications connected to the use of autologous tissues. The use of the cryopreserved fascia allografts from cadaveric donors seems to provide promising and long-standing results in the treatment of facial palsy.

• Coupled systems mechanics
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• v.8 no.3
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• pp.199-218
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• 2019

This paper studies the forced vibration of the hydro-elastic system consisting of the anisotropic (orthotropic) plate, compressible viscous fluid and rigid wall within the scope of the exact equations and relations of elastodynamics for anisotropic bodies for describing of the plate motion, and with utilizing the linearized exact Navier-Stokes equations for describing of the fluid flow. For solution of the corresponding boundary value problem it is employed time-harmonic presentation of the sought values with respect to time and the Fourier transform with respect to the space coordinate on the coordinate axis directed along the plate length. Numerical results on the pressure acting on the interface plane between the plate and fluid are presented and discussed. The main aim in this discussion is focused on the study of the influence of the plate material anisotropy on the frequency response of the mentioned pressure. In particular, it is established that under fixed values of the shear modulus of the plate material a decrease in the values of the modulus of elasticity of the plate material in the direction of plate length causes to increase of the absolute values of the interface pressure. The numerical results are presented not only for the viscous fluid case but also for the inviscid fluid case.