• International Journal of Highway Engineering
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• v.12 no.4
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• pp.165-174
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• 2010

This study was conducted to evaluate the feasibility of expedite repairing of concrete pavements using precast concrete pavement method and to investigate the effectiveness of slab connection methods. In the demonstration construction, four slabs of jointed concrete pavements were replaced with the precast slabs. First, precast concrete slabs were designed and fabricated, then existing slabs were cut and removed, and finally precast slabs were installed. The slabs were leveled and pockets, holes, and space between the slab bottom and the underlying layer were grouted. From the demonstration construction, details about the design and construction of the precast pavements for repairing of pavements were evaluated. In addition, the slab connection methods such as pocket and hole connection methods were applied in the construction and the slab curling behaviors at the joints that include those connection methods were compared. The results showed that both slab connection methods were applicable, and the hole connection method was superior.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.573-578
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• 2001

In order to apply a precast deck to continuous composite bridges, several experiments and analytical studies were performed. Design criterion for crack prevention should be such that it does not permit tension at the joint to occur when the service loads are applied. Details of the shear pocket for studs and material properties of filler in the pocket and the joint are very important considerations in design and construction. Combination of longitudinal prestressing methods, internal tendon and prestressing after shear connection, should be used for prevention of cracking in continuous precast deck bridges. Design guides for the determination of prestressing force are suggested.

• Journal of the Korean Recycled Construction Resources Institute
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• v.11 no.4
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• pp.517-526
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• 2023

To avoid arbitrary design and excessive braces of system supports with high reusability in the field, this study aimed to propose connection conditions for the vertical and horizontal joints of the system supports based on performance evaluation. Disk-type and pocket-type connection materials, widely used in domestic construction sites, were selected for evaluation of rotational stiffness based on load directions(vertical and horizontal) and loading methods (monotonic and cyclic). Contrary to the current design standards specifying a rotational stiffness of "0" for connection materials, the experimental results revealed that, contrary to the current design standards specifying a rotational stiffness of "0" for connection materials, all specimens exhibited rotational stiffness values. The maximum rotational stiffness was observed to be 19.624 kNm/rad in specimens subjected to repeated loading in the vertical direction using disk-type connection materials.

• Journal of Korean Society of Steel Construction
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• v.14 no.1
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• pp.113-120
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• 2002

A shear connection in composite bridges with precast decks has considerable characteristics different from cast-in-place deck bridges such as shear pocket and bedding layer. Thus, it is necessary to build design basis of the shear connector in precast decks through the experiments. In order to estimate fatigue life of shear connector in precast deck bridges, push-out fatigue tests were conducted with parameter, bedding layer thickness. As a result of the tests, failure modes of shear connector were observed. Consequently, empirical S-N curve equations of stud shear connector in precast deck bridges were proposed in this paper.

• Journal of Periodontal and Implant Science
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• v.45 no.1
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• pp.23-29
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• 2015

Purpose: This study was conducted to compare the cumulative survival rates (CSRs) and the incidence of postloading complications (PLCs) between a bone-level internal connection system (ICS-BL) and an external connection system (ECS). Methods: The medical records of patients treated with either a ICS-BL or ECS between 2007 and 2010 at Asan Medical Center were reviewed. PLCs were divided into two categories: biological and technical. Biological complications included >4 mm of probing pocket depth, thread exposure in radiographs, and soft tissue complications, whereas technical complications included chipping of the veneering material, fracture of the implant, fracture of the crown, loosening or fracture of the abutment or screw, loss of retention, and loss of access hole filling material. CSRs were determined by a life-table analysis and compared using the log-rank chi-square test. The incidence of PLC was compared with the Pearson chi-squared test. Results: A total of 2,651 implants in 1,074 patients (1,167 ICS-BLs in 551 patients and 1,484 ECSs in 523 patients) were analyzed. The average observation periods were 3.4 years for the ICS-BLs and 3.1 years for the ECSs. The six-year CSR of all implants was 96.1% (94.9% for the ICS-BLs and 97.1% for the ECSs, P=0.619). Soft tissue complications were more frequent with the ECSs (P=0.005) and loosening or fracture of the abutment or screw occurred more frequently with the ICS-BLs (P<0.001). Conclusions: Within the limitations of this study, the ICS-BL was more prone to technical complications while the ECS was more vulnerable to biological complications.

• Fashion & Textile Research Journal
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• v.11 no.4
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• pp.515-526
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• 2009

From traditional ceremony to science technology, origami was used as technique for artistic creativity and functionality based on formative characteristics. The purpose of this study is to analyze the expressive characteristics of functionality in fashion design using origami technique. The method of this study was to analyze recent documentaries, fashion books, fashion magazines, internet web site and so forth. The results were as follows: In various fields of design, the category of the expressive characteristics was classified as efficient correspondence of space, compositive convergence of function, variable potentiality of form and human ergonomic optimum. In recent origami fashion based on functionality, the efficient correspondence of space was expressed constructive or decorative pocket design, using on clothing surface and varied design by lifestyle. The compositive convergence of function was expressed innovative connection of fashion items or non-fashion items and deconstructed classical clothing pattern. The variable potentiality of form was expressed control of form by irregular fold, dynamic metamorphosis by organic fold and creation of varied clothing silhouette. The human ergonomic optimum was expressed metamorphosis mechanism from two dimension to three dimension, suitable construction to physical ability and limit and organic form based on articular folding. The functional origami fashion means reflection of nomadic lifestyle, maximum of usability, pursuit of playful sensibility, creation of new body aesthetic and pursuit of technology and humanism. And the result of these study may be used for creative inspiration in fashion design because of unique characteristics.

• Structural Engineering and Mechanics
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• v.5 no.4
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• pp.415-431
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• 1997

Stability equations that evaluate the elastic critical axial load of stepped columns under extreme and intermediate concentrated axial loads in any type of construction with sidesway totally inhibited, partially inhibited and uninhibited are derived in a classical manner. These equations can be utilized in the stability analysis of framed structures (totally braced, partially braced, and unbraced) with stepped columns with rigid, semirigid, and simple connetions. The proposed column classification and the corresponding stability equations overcome the limitations of current methods which are based on a classification of braced and unbraced columns. The proposed stability equations include the effects of: 1) semirigid connections; 2) step variation in the column cross section at the point of application of the intermediate axial load; and 3) lateral and rotational restraints at the intermediate connection and at the column ends. The proposed method consists in determining the eigenvalue of a $2{\times}2$ matrix for a braced column at the two ends and of a $3{\times}3$ matrix for a partially braced or unbraced column. The stability analysis can be carried out directly with the help of a pocket calculator. The proposed method is general and can be extended to multi-stepped columns. Various examples are include to demonstrate the effectiveness of the proposed method and to verify that the calculated results are exact. Definite minimum bracing criteria for single stepped columns is also presented.

• The Research Journal of the Costume Culture
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• v.12 no.5
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• pp.880-896
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• 2004

Trompe l'Oeil technique strategically conceived with a view to effectively realize creative ideas among the expression techniques of fine arts style has provided the driving force in development of fine arts and has continuously influenced development of the modem fashion pursuing unique individuality. The study is focused first on finding out how Trompe l'Oeil technique originated in connection with researching the fashion of Trompe l'Oeil and on analysing the technique of expression. The author referred to fashion magazines for designing ideas of Trompe l'Oeil represented in modem fashion in practical applications used by designers in Paris, Italy, London and New York during the 10 year period(1990-1999). The collections of data were analyzed as following: Effectiveness depending on the method of Trompe l'Oeil I. Effectiveness of Layering: when two clothing are over lapped or coordinated with one another in color or style. 2. Effectiveness of Detailing: when pictures, stitch, tape, cutting, quilting and etc are used to create collar, pocket, yoke, zipper, string, shadow and etc. 3. Effectiveness of Accessories: when the image of necklace, belt, tie, tassel, badges and stars are represented by illustration or embroidery on clothing to substitute the actual existence. 4. Effectiveness of Nudity: when human body is realistically drawn and printed on clothing.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.2
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• pp.202-208
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• 2016

In this study, the defect in connection with a C-tray was inspected using a low-cost camera. The four test items were the device overlapping in the tray, the bending of the tray, the loaded quantity of the tray, and the device pocket leaving, an algorithm was developed for defining and detecting the above defect types. Therefore, the developed handling system could extend the application of the stack of the c-tray and provide a quantity verification inspection on the packing processing. The machine operation control program, which can ensure the optimal inspection image to match the scan speed, was developed and the control program that can process the user gui and the vision image utilizing the control was developed. Overall, a mechanical system that is practicable for obtaining an image and processing the vision data was designed.

• Journal of Digital Contents Society
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• v.7 no.3
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• pp.161-168
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• 2006

Wibro(Wibro - Wireless Broadband Internet ) is a system that can accept effectively the IP-based Wireless data traffic with upward / downward asymmetric transfer characteristic by using a Wirelss broadband transfer technology in OFDMA/TDD (Orthogonal frequency Division Multiple Access/Time Division Duplex). Wibro service should support handover to maintain connection continuously in movement because the service is based on If system which is different from cellular system. Current Micro Mobility system and general Mobile If system has got a problem of delayed speed and lost packets during handover. IETF protocol has been proposed for minimizing this problem and its standardization is under process, mainly focused on Mip4, Mip6 and Mipshop WG. This article studies and analyzes an effective method of minimizing handover delay to improve the problem of WiBro system and its revitalization & outlook.