• Journal of The Korean Institute of Defense Technology
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• v.5 no.4
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• pp.1-8
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• 2023

In this study the economic impact of each plan for introducing Korea unclear-powered submarines were analyzed. This study conducted a preliminary investigation into foreign countries cases of unclear-powered submarines and classified three introduction plans. In order to analyze the economic impact of each introduction plan, a multiple-level survey was conducted targeting experts with experience in developing and operating ship weapon systems, and quantitative results were calculated for subcategory items with industrial relevance for industrial correlation analysis. The value added inducement coefficient and production inducement coefficient and employment inducement coefficient were calculated for each introduction method, and a favorable introduction method was derived. It is hoped that the results of this study will serve as a reference for policy decision-making during prior research for the introduction of korea nuclear submarines.

• Journal of the Korean Society for Precision Engineering
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• v.10 no.2
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• pp.161-169
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• 1993

The elimination of chatter vibration is necessary to improve the precision and the productivity of the cutting operation. A new mathematical model of chatter vibration is presented in order to predict the dynamic cutting force from the static cutting data. The dynamic cutting force is analytically expressed by the static cutting coefficient and the dynamic cutting coefficient which can be determined from the cutting mechanics. The stability analysis is carried out by a two degree of freedom system. The chatter experiments are conducted by exciting the cutting tool with an impact hammer during an orthogonal cutting. A good agreement is shown between the stability limits predicted by theory and the critical width of cut determined by experiments.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.113-114
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• 2023

This study measured the thickness and speculation coefficient of the coating for existing buildings and calculated the diffusion coefficient of the coating to predict the depth of carbonation through numerical analysis in order to evaluate the impact of the external finish and local environment. As a result, it was possible to predict the short-term and long-term carbonation depth of reinforced concrete buildings coated with coating film with considerable reliability.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.7 s.178
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• pp.1712-1720
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• 2000

• Industry Promotion Research
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• v.9 no.2
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• pp.23-28
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• 2024

The study investigated the impact of ESG management activities on the non-financial performance of organizations, focusing on small and medium-sized manufacturing companies. Using data from 78 survey responses, the following results were summarized. Firstly, ESG management activities positively influenced internal customer satisfaction. The correlation coefficient was .679, indicating a moderately strong correlation, and the coefficient of determination (R²) was .461, explaining 46.1% of the variance. Additionally, with a beta value of .679, a t-value of 8.058, and a p-value of .000, ESG management activities had a statistically significant impact on internal customer satisfaction. Secondly, ESG management activities also had a positive impact on corporate trust. The correlation coefficient was .695, indicating a moderately strong correlation, and the coefficient of determination (R²) was .483, explaining 48.3% of the variance. The beta value was .695, the t-value was 8.429, and the significance probability was .000, indicating a significant influence on corporate trust.The study aimed to shed light on the relationship between ESG management activities of small and medium-sized enterprises and their non-financial performance. These results suggest that companies can enhance internal customer satisfaction and corporate trust through fulfilling social responsibilities and practicing sustainable management.

• Journal of Power System Engineering
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• v.13 no.6
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• pp.123-128
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• 2009

The effects of temperature and initial crack length on the impact fracture behavior for the side plate material of FRP ship were investigated. And the effects of the counterpart roughness and sliding distance on the volumetric wear of same material were investigated as well. Impact fracture toughness of GF/PE composites displayed maximum value when the temperature of specimen is room temperature and $50^{\circ}C$, and with decreasing the temperature of specimen, impact fracture toughness decreased. Impact fracture energy of GF/EP composites decreased with increasing the initial crack length of specimen, and this value decreased rapidly when the temperature of specimen is lowest, $-25^{\circ}C$. It is believed that sensitivity of notch on impact fracture energy were increased with decreasing the temperature of specimen. With increasing the sliding distance, the transition sliding distance, which displayed different aspect on the friction coefficient and the volumetric wear loss, were found out. Counterpart roughness had a big influence on the wear rate at running in period, however the effect of counterpart roughness became smaller with sliding speed increase in. Volumetric wear loss were increased with increasing the applied load and the counterpart roughness.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.6
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• pp.245-252
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• 2022

This study examines the strength of the impact of fiscal policy tools on economic wellbeing as measured by per capita income in Malaysia from 1996 to 2020. The impact of fiscal policy instruments on economic wellness, represented by real income per capita, is measured using the autoregressive distributed lags model. The speed of adjustment from short-run disequilibrium to long-run equilibrium is also measured to assess the strength of the fiscal instruments' impact on per capita income. Empirical results exhibit the existence of co-integration relationships between per capita income, tax revenue, and government spending. The findings provide strong support for the presence of a long-run positive impact on government spending and a long-run negative impact of tax revenue on per capita income. The coefficient of ECT_t-1 indicates that deviations from a short-run disequilibrium to a long-run equilibrium from the current to the future period are corrected with a speed of 76% (equivalent to a duration of 1.5-2 years to return to equilibrium). The practical and policy implication of the results is fiscal instruments play a significant role, mainly in alleviating the economic impact of the COVID-19 pandemic in the long run.

• Current Optics and Photonics
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• v.2 no.2
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• pp.119-124
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• 2018

The errors in retrieved aerosol backscattering coefficients due to different lidar ratios are analyzed quantitatively in this paper. The actual calculation shows that the inversion error of the aerosol backscattering coefficients using the Fernald backward-integration method increases with increasing inversion distance. The greater the error in the lidar ratio, the faster the error in the aerosol backscattering coefficient increases. For the same error in lidar ratio, the smaller actual aerosol backscattering coefficient will get the larger relative error of the retrieved aerosol backscattering coefficient. The errors in the lidar ratios for dust or the cirrus layer have great impact on the retrievals of backscattering coefficients. The interval between the retrieved height and the reference range is one of the important factors for the derived error in the aerosol backscattering coefficient, which is revealed quantitatively for the first time in this paper. The conclusions of this article can provide a basis for error estimation in retrieved backscattering coefficients of background aerosols, dust and cirrus layer. The errors in the lidar ratio of an aerosol layer influence the retrievals of backscattering coefficients for the aerosol layer below it.

• Transactions of the Korean Society of Mechanical Engineers
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• v.14 no.2
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• pp.288-297
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• 1990

The method of analyzing flexible mechanisms with clearances was studied considering flexibility of beams in the mechanism using finite elements. Both ends of a beam were modeled as free following Dubowsky's impact pair model. Instead some force constraints were imposed at imposed at the connections between adjoining links. Coulomb model has been developed using dry frictions in place of tangential damping forces in the impact pair model and the contact compliance and damping coefficient approximated in a form of root function were used. As examples, impacts of a rigid ball in a cylinder, impact beam model and four-bar mechanisms made up of three flexible links with clearance connections were simulated numerically. The results from examples showed similar but a little bit smaller magnitude of impact forces compared with published studies.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2005.03a
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• pp.228-235
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• 2005

The floor impact sound insulations are installed frequently for reducing the floor impact sound into the floor slab of the residential buildings in recent years. Therefore the analytical FE model considering the insulations is needed for the sound and vibration analysis of the floor and it is necessary to use a refined finite element model for considering the large number of modes involving in the dynamic responses. So it is very difficult to use FE model because of the tiresome task for constructing the FE model, taking a lot of times for analysis and the impossibility of using the proportional damping. The efficient analysis and modeling method are proposed to the dynamic analysis for the floor with floor impact sound insulations in this study. The floor slabs and finished layers are modeled individually and the spring elements that mean floor impact sound insulations use to connect two parts. The dynamic analysis by the $Newmark-{\beta}$ method is performed to solve the non-proportional damping problem due to the damping coefficient of insulations .