• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.8
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• pp.805-815
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• 2008

Transfer path analysis(TPA) and panel contribution analysis(PCA) have been used widely to reduce interior noise of mechanical systems. TPA enables us to decompose interior noise into air-borne and structure-borne noises and estimate the path contribution of noise sources. PCA is also used to identify the noise contribution of each sub-panel in vibro-acoustic systems. In this paper, TPA and PCA are applied to wheel loader, one of the heavy construction equipments. Firstly, TPA for air-borne noise is conducted to estimate the contribution of air-borne sources using pressure transfer function. Thereafter, TPA for structure -borne noise is employed to verify the results of air-borne source quantification through the synthesis of two results. Secondly, PCA is performed by both TPA using pressure transfer function between panels inside the cabin and boundry element method(BEM) for the cabin of wheel loader with various boundary conditions. As a results, it was found that TPA conducted by experiments and PCA accomplished by both experiments and BEM are very effective methods in analyzing the path and contribution of the noises for reducing an interior noise level in the wheel loader system.

• Knowledge Management Research
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• v.16 no.1
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• pp.55-69
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• 2015

Employees' knowledge contribution is one of the critical activities that maximize internal capability of the firm and facilitate organizational innovation by sharing scattered internal knowledge. This study integrates antecedents of knowledge contribution based on the theory of planned behavior(TPB). Utilizing TPB as a theoretical framework, expected reciprocity, subjective norm, and self-efficacy's direct effects on knowledge contribution were assessed. Additionally, interaction effects among expected reciprocity, subjective norm, and self-efficacy were explored. As the results of analysis, all the antecedents significantly influenced knowledge contribution. Interestingly, when the knowledge source's self-efficacy was high, the influence of expected reciprocity on knowledge contribution was decreased. Similarly, when the knowledge source's subjective norm for knowledge contribution was high, expected reciprocity's effect was weakened. This implies that when facilitating knowledge contribution, interaction effects among antecedents of knowledge contribution, as well as their direct effects, should be considered.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.361-370
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• 2019

This study examined the importance of social contribution through the existing research data on social contribution and the progress of social contribution activities of public institutions in Wonju Innovation City. The social contribution activities of nine organizations out of 14 public institutions were analyzed in detail and suggested the right direction of social contribution activities of public institutions based on this analysis. First, recent trends are being developed to cooperate with local communities through public interest activities rather than simple donations or sponsored forms of social contribution. Second, the synergy effect was maximized by systematically approaching local communities rather than a one-time, one-off social contribution. Third, it should contribute to the revitalization of the local economy in the mid- and long-term by creating a social economy in cooperation with local civil society rather than a one-sided social contribution.

• Journal of KSNVE
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• v.9 no.4
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• pp.785-794
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• 1999

The panel contribution analysis to reduce interior booming noise of a passenger car is carried out using both experimental method and numerical one. The accelerations of panels are measured on the outer surface of car body during operation. The acoustic characteristic of cavity is represented by two different ways. One is the acoustic transfer function obtained by experiment with reciprocal manner. The other is the boundary element model and numerical results of the model are calculated using SYSNOISE. The results from numerical method show more good agreement with measured sound pressure levels than the experimental one. Contributions of panels for interior noise are ranked and structure of the car is reinforced according to the results, which shows that the panel contribution analysis is a powerful tool to lessen structure-borne noise of passenger vehicle.

• Journal of Drive and Control
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• v.19 no.4
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• pp.77-84
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• 2022

The aims of this study was to estimate transfer force delivered to cone crusher housing and contribution of force transmission. The rock crushing condition caused vibrations in the cone crusher housing, which were experimentally measured, and frequency response functions (FRF) were also found through modal impact tests. Vibration data and frequency response functions were applied to the transfer path analysis (TPA) model. Next, transfer forces delivered to the cone crusher housing were quantified via the TPA method. Contribution of force transfer was also analyzed based on force estimation results. Finally, this study describes basic concepts and components of the TPA method and reviews its applicability to rotating machinery that experiences impact vibrations and forces.

• Journal of Information Technology Applications and Management
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• v.28 no.6
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• pp.117-132
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• 2021

Based on the core value of the Q&A community, the contribution of knowledge and information has a great impact on users' community evaluation. As a small social group, the relationships and interactions among community members are quickly formed through information technology. As such, the cognitive evaluation of the relationship between community members will have an impact on the intention of information contribution. This research builds on the previous research based on the social exchange theory and establishes a dual model of swift guanxi in examining the relationship between guanxi and continuous knowledge contribution. In the current study, 305 survey questionnaires were used and 249 valid questionnaires were used for analysis. The analysis results are as follows: First, information support has a positive impact on dedication-based swift guanxi. While hypothesis between information support and constraint-based swift guanxi was not be supported. Second, emotional support has a positive impact on the formation of swift guanxi from a dual perspective. Third, the swift guanxi from the dual perspective has a positive impact on the intention of continuous knowledge contribution. Finally, although personal involvement has an adjustment effect, it is a downward adjustment effect, hypotheses are not supported. The current study offers theoretical and practical implications in field of knowledge management, specifically knowledge contribution in the virtual community.

• Journal of Information Science Theory and Practice
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• v.3 no.1
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• pp.66-76
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• 2015

This research uses a new approach to analyze the extent of influence journal papers have on the progress of varied research fields by estimation of subject-based influence on research other than impact factor that relies on citation index. It is initiated with the hypothesis that earlier established citation relations between journal and citing paper, which reveals the research field that contains the highest citation index and hence has received the greatest contribution from a particular journal, would have inconsistent contribution to the research field over the year of journal publication. The target research is primarily 128 journal papers and 4,123 citing papers from Information Systems Research published in the years 2001, 2004, 2007, and 2010. The characteristics of citation history and hallmarks of research field of citing papers were studied and analysis on significant distinction between citing fields based on the year of publication was performed. The analysis results show the order of citation rate to be highest from Computer Science (2,221 cases), Business & Economics (2,191 cases), and Information Science & Library Science (1,901 cases). The citation history of the journal, nonetheless, indicates increase in citation during 2-3 years after the earliest publication till it achieves constant citation. The statistical analysis shows significant variation in citing fields in accordance with the publication year; especially in 2010, journal contribution has increased in the fields of Business & Economics, Operations Research & Management Science, and Health Care Sciences & Services but, however, is reduced in Education & Educational Research and Social Sciences - Other Topics.

• Journal of Preventive Medicine and Public Health
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• v.38 no.1
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• pp.107-116
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• 2005

Objectives : We analyzed the changes from 1996 to 2002 in distributive equity of the contribution burden in the Korean National Health Insurance. Methods : The study subjects were a total of 8,923 employee households and a total of 7,296 self-employed households over the period from 1996 to 2002. Those were the households meeting the two criteria as completing each annual survey and having no change in the job of head of the household during that period from the raw data of the Household Income and Expenditure Survey annually conducted by the Korean National Statistical Office. The unit of analysis was a household, and this was the standard for assessing the contribution that is now applied on a monthly basis. Deciles Distribution Ratio, Contribution Concentration Curve and Contribution Concentration Index were estimated as the index of inequality. Multiple regression analysis was conducted to compare the annual ability-to-pay elasticity of the contribution to the reference year of 1996 for three groups (all households, the employee households, and the self-employed households). Results : For the index of inequality, the distributive equity of contribution was improved in all three groups. In particular, the employee group experienced a substantial improvement. Using multiple regression analysis, the ability-to-pay elasticity of the contribution in the employee group significantly increased ($\beta$=0.232, p<0.0001) in the year 2002 as compared to the reference year of 1996. The elasticity in the self-employed group also significantly increased ($\beta$=0.186, p<0.05), although its change was smaller than that in the employee group. Conclusions : The employee group had a greater improvement for the distributive equity of the contribution burden than the self-employed group. Within the observation period, there were two important integration reforms: one was the integration of 227 self-employed societies in 1998 and the other was the integration of 139 employee societies in 2000. We expected that the equity of the contribution burden would be improved for the self-employed group since the integration reform of 1998. However, it was not improved for the self-employed group until the year 2000. This result suggests that capturing exactly the beneficiaries' ability-to-pay such as income is the precedent for distributive equity of the contribution burden, although a more sophisticated imposition standard of contribution is needed.

• Journal of Korean Society on Water Environment
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• v.26 no.6
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• pp.1016-1027
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• 2010

The phosphorus contribution rate on water quality of North and South-Han River, and Gyungan-cheon by effluents from environmental fundamental facilities located in upstream basin of Paldang Lake were analyzed. QUALKO2 model was selected for the analysis of contrubution rate, and was constructed considering the location of the main point sources and all facilities in study area. The pollutant loading rates and arrival rates for each unit-watershed in study area were calculated for model operation. For the calibration and verification of model, 2006 water quality dataset from Ministry of Environment and the effluent loadings of the environmental fundamental facilities were used. Reliability Index (RI) method was used to estimate the validity of the results of calibration and verification. The phosphorous contribution rate(%) for each environmental fundamental facility were analyzed by excepting the effluent loading of the facility. The contribution rate was analyzed for each facility, facility groups separated by each main river and each unit-watershed. The main results of analysis for each facility are as follows; (i) the phosphorous contribution of B1 facility is 50%, which is the highest phosphorous contribution rate among those of nine facilities in the North-Han River Basin; (ii) the highest phosphorous contribution is 55.6% from J facility among eight facilities in the Gyungan Stream Basin; (iii) 40% from E treatment facility is the highest among those of twenty eight facilities in the South-Han River Basin.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.806-811
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• 2007

In this study, we propose a more systematic design process for the structure-borne noise. The proposed way consists of 4 steps: Problem definition, Cause analysis, Development of counter-measure and Validation. Especially, we improved the second step: Cause analysis. According to the PCA(Panel Contribution Analysis), a reduction in vibration of the panels of which panel contribution is positive and larger, results in a reduction in structure-borne noise. We have, however, met the case in which the concept of PCA is no valid in a few vehicle tests. In order to understand this phenomenon, we compared the major panels selected by PCA with the one chosen by DSA(Design Sensitivity Analysis). After investigating the difference between the two results, a more improved process is suggested. The proposed one for the second step in the design process consists of not only the previous way: PCA with deformation analysis results but also DSA. It is finally validated that the proposed design process decreases the sound pressure of the concerned noise transfer function more than 3.5 dB.