• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.7
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• pp.647-652
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• 2016

Guided waves can be used for the inspection of long range pipelines. Surface corrosion is often found as a major defect type in pipelines. The reciprocity relation is a well-established theorem by which one can simplify complicated mathematical expressions. The approach has been already applied to plate and half-space structures to obtain the closed-form solutions of scattered amplitude. However, results for the case of cylindrical structures have not been reported yet. In this paper, the scattering of torsional waves, which is widely used in commercial applications, is explored by the reciprocity theorem approach. Obtaining closed-form solutions of the amplitudes of propagating waves is much simplified by using the reciprocal relation. The scattered amplitudes for elliptical and rectangular defect shapes are calculated with respect to defect depth and width, at frequencies between 0 and 500 kHz. The amplitude shows the periodic result as a function of frequency. The derived closed-form solutions can play a significant role in quantitative signal interpretation.

• The Journal of the Korea Contents Association
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• v.10 no.1
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• pp.122-137
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• 2010

Blogs are a new type of media that have recently become popular on the World Wide Web and have influence throughout society. The purpose of this study is to examine social motivations influencing intention of blog usage. Based on Technology Acceptance Model and Motivation Theory, this study considered perceived usefulness, perceived ease of use, reputation, reciprocity, enjoyment of helping, social identity as the determinants of influencing the intention to use of blog. The suggested model was empirically evaluated using online survey data collection from 342 users of popular blog site in Korea (NAVER Blog, Cyworld minihompy, Daum Blog, and Yahoo Blog). The results revealed that perceived usefulness, perceived ease of use, reciprocity, and social identity affect directly the intention of blog usage. Furthermore, social identity has moderate effect via reciprocity and enjoyment of helping on blog usage. This study contributes to a theoretical understanding of the factors as social motivation that affects the usage of blogs. Also, the results of this study provide blog service providers useful strategic insights and service guidelines to enhance user's intention of blogs practically.

• Journal of the Economic Geographical Society of Korea
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• v.21 no.3
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• pp.254-269
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• 2018

The aim of this paper is to identify the components of the sustainable regional ecosystem of social economy enterprises (hereafter 'regional ecosystem'), and to explore the principles of reciprocity, regard and public policy, which have a fundamental impact on the development of such regional ecosystem. The regional ecosystem is an interactive system of the stakeholders who are related to the process of planning, producing, distributing and selling goods and services, and the agents who maintain and spread their social value orientation. This system operates through the interaction of 'local network (business relations and social relations)', 'intermediary organization' and 'public role.' On the basis of the conceptual framework on the regional ecosystem, the result of the in-depth analysis on the case of Gorang-erang Coop shows the interaction of reciprocity and public policy with respect to regard within the context of a characteristic of the regional ecosystem.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.2
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• pp.424-442
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• 2014

Most recent research on iterative solutions for interference alignment (IA) presents solutions assuming channel reciprocity based on the suppression of interference from undesired sources by using an appropriate decoding matrix also known as a receiver combining matrix for multiple input multiple output (MIMO) interference channel networks and reciprocal networks. In this paper, we present an alternative solution for IA by designing precoding and decoding matrices based on the concept of signal leakage (the measure of signal power that leaks to unintended users) on each transmit side. We propose an iterative algorithm for an IA solution based on maximization of the signal-to-leakage-and-noise ratio (SLNR) of the transmitted signal from each transmitter. In order to make an algorithm removing the requirement of channel reciprocity, we deploy maximization of the signal-to-interference-and-noise ratio (SINR) in the design of the decoding matrices. We show through simulation that minimizing the leakage in each transmission can help achieve enhanced performance in terms of aggregate sum capacity in the system.

• The Journal of the Acoustical Society of Korea
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• v.8 no.5
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• pp.23-32
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• 1989

The calibration of 1 inch standard condenser microphone is done by the reciprocity calibration method. There are two kinds of reciprocity calibration, free-field calibration and pressure calibration. The pressure sensitivities of the three 1 inch condenser microphones are determined by pressure calibration. The accuracy of the pressure sensitivity of the microphone depends on the accuracies of the voltage and dimension measurements as well as the various corrections for the coupler. If the individual accuracies for the measurements and corrections are achieved, it is estimated that the over-all accuracy is approximately 0.05dB at low and middle frequencies decreasing to about 0.ldB over 10kHz.

• Asian Journal of Business Environment
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• v.10 no.2
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• pp.5-15
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• 2020

Purpose: This study examines the impact of individual reciprocal preferences on coalition formation. The reciprocal model considers a player's own payoff, the player's perception of others' payoffs, and others' perceptions of the player's payoff. Research design, data and methodology: A reciprocal model is built to illustrate how reciprocity influences individual decisions in a coalition game and its formation. The prediction is examined with experimental evidences from a dictator game and a membership game. Results: The theoretical result suggests that the coalition formation could be unstable due to negative reciprocal kindness. The experimental findings support that negative reciprocal kindness could lead players participating in a coalition, no matter their dominant strategies are. When subjects were essential to make contributions to a coalition, they were more likely to cooperate if they were treated badly. In contrast, when subjects were unnecessary, the reciprocal kindness could enhance cooperative tendencies. Conclusions: This study reveals that the reciprocal behavior could influence individual decisions and reshape the coalition formation. In terms of policy implications, this study has shown that coalition formation could be reshaped by reciprocal prefe rences. Due to the strategic and complicated decision process in an interactive environment, a comprehensive investigation of factors would be required in a climate coalition in practice.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.2
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• pp.243-253
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• 1999

The dual reciprocity boundary element method (DRBEM) is used to solve the Graetz problem of laminar flow inside circular duct. In this method the domain integral tenn of boundary integral equation resulting from source term of governing equation is transformed into equivalent boundary-only integrals by using the radial basis interpolation function, and therefore complicate domain discretization procedure Is completely removed. Velocity profile is obtained by solving the momentum equation first and then, using this velocities as Input data, energy equation Is solved to get the temperature profile by advancing from duct entrance through the axial direction marching scheme. DRBEM solution is tested for the uniform temperature and heat flux boundary condition cases. Local Nusselt number, mixed mean temperature and temperature profile inside duct at each dimensionless axial location are obtained and compared with exact solutions for the accuracy test Solutions arc in good agreement at the entry region as well as fully developed region of circular duct, and their accuracy are verified from error analysis.

• The Korean Journal of Community Living Science
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• v.19 no.4
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• pp.509-518
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• 2008

The purpose of this study was to explore how job characteristics, housework factors (reciprocity) and family characteristics influence the health status of a husband and wife. To do this, the study used the ordered probit estimation model. The results of this study were as follows: the status of the husband's health was perceived to be slightly better than that of the wife. age, the husband's job satisfaction and wife's future job prospects were found to impact upon the health status of both the husband and the wife. In addition, the health of the husband was found to be significantly influenced by household income and his wife's perceived fairness of housework. On the other hand, the influencing factors upon the health status of the wife were her education, child caring responsibilities, her husband's future job prospects, as well as the flexibility of her work schedule and hours of work.

• Knowledge Management Research
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• v.17 no.1
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• pp.113-133
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• 2016

Why illegal digital contents sharing happens? This study pays attention to the fact that file sharing is an exchanging behavior between people and it is expanding despite of an illegal behavior and proposes that it is necessary for the phenomenon to be understood from social cultural point of view beyond a personal dimension. Based on the social exchange theory, this study demonstrates effects of file sharing attitudes and continuity, regarding 'group norm', 'popular demand', 'reciprocity' and 'social solidarity' as main factors. The main findings of this study are as followed;- First, it is shown that a tacit agreement of a group on file sharing is a determinant of positive attitude to file sharing and the intent of continual file sharing. Second, it is not found that the social relationship factors that are regarded as potential influential factors on file sharing attitude have effects on file sharing behavior, except for 'group norm'. Unlike previous studies, the results may come from the fact that this study deals with an illegal behavior. The third finding indicates a structural relationship between social relationship factors. When members of a group have more amicable attitude to file sharing including silence or a tacit agreement on file sharing, more people ask illegal sharing of files that they need. Such public demand creates expectation of reciprocity. As reciprocity maintains, social connectedness is strengthened. Then, strong social connectedness escalates the intent to maintain file sharing. It is important to notice that this study promotes understanding of how digital contents sharing happens by structuring and demonstrating influential relationship between characteristic factors of the social relationship.

• Child Health Nursing Research
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• v.11 no.4
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• pp.444-455
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• 2005

Purpose: This study examined the efficacy of parent training interventions to facilitate social reciprocity and language development in children with autism. Methods: The social interaction behaviors of mothers and children over time were compared using single subject design experimentation methodology. five children who were diagnosed with autism and their mothers participated in the study. The participants were recruited from U city, Korea. The mothers were trained using training videotapes and demonstrations on how to facilitate social interaction with their children as well as promoting language development. following the training, data were collected three times per week by video taping mother-child interaction in their homes. Results: Four of the five mothers demonstrated increases in the use of imitation with animation and expectant waiting after the intervention compared to the baseline sessions; the children demonstrated noticeable increases in the use of initiation of interaction, vocalizations, and verbal production after their mothers received the training intervention. Conclusion : Results of this study demonstrate the efficacy of mother training to improve social interactions of children with autism. Additional important information can be gained by replicating this study with more participants and comparing intervention and control groups. Clearly, this intervention shows promise and has implications far clinical practice.