• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.6
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• pp.29-35
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• 2013

The heterogeneous emergency communication radios is used at disaster management agencies of Korea to response activity in the event of disaster. The compensation method by communication connection time difference is necessary to seamless voice communication because radios have different communication method and delay. In this paper, we suggested solution for voice transmission chance and data loss problem.

• Korean Journal of Child Studies
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• v.29 no.4
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• pp.181-197
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• 2008

A mobile phone usage survey was administered to a nationwide sample of 3,617 adolescents. Major motivations of mobile phone usage were mobility/real-time connection, show off, information acquisition, entertainment, dialogue, schedule management, and advice. Maintenance of social relationship with the peer group was most important in mobile phone use. Motivations influenced mobile phone dependency : show off had the strongest influence on anxiety/paranoia followed by dialogue, entertainment, mobility/real-time connection. Without their phones, fashion-oriented adolescents showed mobile phone dependency and anxiety. Stronger dialogue and entertainment motivations were associated with weaker real time connection motivation and stronger paranoia symptoms. Mobile phone dependent adolescents had lower grades, showed lack of attention, had little dialogue with their parents and showed withdrawal from the peer group.

• Journal of the Korea Society for Simulation
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• v.13 no.2
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• pp.53-63
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• 2004

In ad hoc networks, the link survivability is firstly considered if a routing between two mobile nodes takes place through wireless environments, because all of mobile nodes participating in a connection dynamically move to anywhere. Also, mobile nodes have multi-role to implement a communication without a static system supported by wired networks. Hence, it is difficult that all mobile nodes continuously provide a reliable connection when the nodes operate each role for the connection. Therefore, it is desired to maximize the lifetime of a route as long as possible for the reliable communication. In this paper, we propose a proactive link management scheme that can provide the continuous route supported by the link handover. It consider the wireless link quality and the power lifetime of a node so that the link handover is implemented for the link survivability without disconnecting the route on the communication.

• Steel and Composite Structures
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• v.25 no.1
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• pp.1-17
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• 2017

Seismic performance of hybrid steel frames defined as mixture of rigid and semi-rigid connections is investigated in this paper. Three frames with 10, 15 and 20 stories are designed with fully rigid connections and then with 4 patterns for semi-rigid connection placement, some of beam to column rigid connections would turn to semi-rigid. Each semi-rigid connection is considered with 4 different moment capacities and all rigid and semi-rigid frames consisting of 51 models are subjected to 5 selected earthquake records for nonlinear analysis. Maximum story drifts, roof acceleration and base shear are extracted for those 5 earthquake records and average values are obtained for each case. Based on numerical results for the proposed hybrid frames, story drifts remain in allowable range and the reductions in the maximum roof acceleration of 22, 29 and 25% and maximum base shear of 33, 31 and 54% occur in those 10, 15 and 20-story frames, respectively.

• Proceedings of the KIEE Conference
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• 2001.04a
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• pp.485-487
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• 2001

Electric power has traditionally been supplied to the demander through power generation, its transmission, and final distribution system. It is, however, expected that the various dispersed power system will be located near demanders and act as a power source based on the efficient management of electric power demanders and the optimal utilization of substitute energy. More stable electric power and efficient utilization of various power sources can be guranteed through the connection of the dispersed power system into the existing power system. It is the purpose of this study that, in the case of the connection of dispersed power system into the existing distribution line, effects of the connection on the power quality and plans for protection of power equipments are discussed and solutions of them are proposed.

• Journal of The Korea Institute of Healthcare Architecture
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• v.20 no.1
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• pp.45-55
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• 2014

Purpose: The purpose of this study is to provide data on the basis for architectural planning of floor plan type and spatial composition by analysing standard mental health centers in Seoul. Methods: Data were collected through literature research, field surveys, and expert interviews to 22 standard mental health centers in Seoul. Results: The results of this study could be summarized as follows; Firstly, Mental Health Center is divided into five types according to the location. Location types of mental health center were 'Director type', 'Health center connection type', 'Public facilities connection type', 'Complex center connection type' and 'Commercial Facilities connection type'. Secondly, Depending on the type of management a mental health center is divided into two types. Types are 'Complex type' and 'Independent type'. Average area of 'Complex type' is $192.99m^2$ and 'Independent type' is $266.87m^2$. This difference affects the various spaces. Implications: It is necessary to give and architectural suggestion of mental health center in response to the proposal of the system.

• Structural Engineering and Mechanics
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• v.88 no.1
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• pp.43-52
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• 2023

This paper handles the results of an extensive parametric study on the rotational stiffness of the flexible base connection using ABAQUS program. The results of the parametric study show the relation between the applied moment and the relative rotation for 96 different base connections. The configurations of the studied connections considered different numbers, diameters, and spacing of the anchor bolts along with different thicknesses of the base plate to investigate the effect of these parameters on the rotational stiffness behavior. The results of the previous parametric research used through the whale optimization algorithm (WOA) to detect different equation formulation of the moment-rotation (M-Ɵ_r) equation to detect optimum equation simulates the general nonlinear rotational behavior of the flexible base connection considering all variables used in the parametric study. WOA is a relatively new promising algorithm, which is used in different types of optimization problems. For more verification, the classical genetic algorithm (GA) is used to make a comparison with WOA results. The results show that WOA is capable of getting an optimum equation of the M-Ɵ_r relation, which can be used to simulate the actual rotational stiffness of the flexible base connections. The rotational stiffness at H/150 can be calculated using WOA (1) method and be used as a design aid for engineering design.

• Journal of Korean Home Economics Education Association
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• v.16 no.3
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• pp.27-41
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• 2004

The purpose of this study is to analyze connection of the field on 'Nutrition and Food' among grades in the Practical Arts and Home Economics. The subject of analysis is 'Practical Arts' textbook in elementary school and 'Home Economics' textbook in middle school and high school. The Practical Arts textbook of 5th, 6th grade and 5 Home Economics textbooks middle school 1st, 3rd and high school. First of all, it is arranged the aim and contents, used analysis connection frame. The following contents are to summarize the result. First, 'Nutrition and Food' unit is presented nutrition, food, meals management in textbook. Second, aim in curriculum is agreed with contents in curriculum, but how to description in textbook is needed agreements. Third, contents in elementary school and secondary school is connection to develope, but contents in middle and high school are repetition. With the results analyzing connection among text contents, it is concluded that contents' connection has more developed and repeated. Specially, contents of Nutrition are mostly developmental contents, contents of Food are that one part is developmental contents and the other part is repeated contents.

• Smart Structures and Systems
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• v.26 no.1
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• pp.103-115
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• 2020

The cold-formed steel storage racks are extensively employed in various industries applications such as storing products in reliable places and storehouses before distribution to the market. Racking systems lose their stability under lateral loads, such as seismic actions due to the slenderness of elements and low ductility. This justifies a need for more investigation on methods to improve their behavior and increase their capacity to survive medium to severe loads. A standardized connection could be obtained through investigation on the moment resistance, value of original rotational stiffness, ductility, and failure mode of the connection. A total of six monotonic tests were carried out to determine the behavior of the connection of straight 2.0 mm, and 2.6 mm thickness connects to 5 lug end connectors. Then, the obtained results are benched mark as the original data. Furthermore, an extreme learning machine (ELM) technique has been employed to verify and predict both moment and rotation results. Out of 4 connections, increase the ultimate moment resistance of connection by 13% and 18% for 2.0 mm and 2.6 mm upright connection, respectively.

• The Journal of Advanced Prosthodontics
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• v.11 no.3
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• pp.147-154
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• 2019

PURPOSE. This study aimed to evaluate the effect of two different implant-abutment connection structures with identical implant design on peri-implant bone level. MATERIALS AND METHODS. This clinical study was a patient-blind randomized controlled trial following the CONSORT 2010 checklists. This trial was conducted in 24 patients recruited between March 2013 and July 2015. Implants with internal friction connection were compared to those with external hex connection. One implant for each patient was installed, replacing the second molar. Implant-supported crowns were delivered at four months after implant insertion. Standardized periapical radiographs were taken at prosthesis delivery (baseline), and one year after delivery. On the radiographs, distance from implant shoulder to first bone-to-implant contact (DIB) and peri-implant area were measured, which were the primary and secondary outcome, respectively. RESULTS. Eleven external and eleven internal implants were analyzed. Mean changes of DIB from baseline to 1-year postloading were 0.59 (0.95) mm for the external and 0.01 (0.68) mm for the internal connection. Although no significant differences were found between the two groups, medium effect size was found in DIB between the connections (Cohen's d = 0.67). CONCLUSION. Considering the effect size in DIB, this study suggested the possibility of the internal friction connection structure for more effective preservation of marginal bone.