• Journal of Power System Engineering
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• v.21 no.3
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• pp.37-44
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• 2017

In this study, failure analysis of the angular pin for molding machines to aluminum component molding was carried out. SM45C steel was used for the angular pin, it was surface hardened by the induction surface hardening heat treatment. The cross section of damaged angular pin was observed, and micro Vickers hardness value from the fractured part was measured. Brittle fracture was occurred from the fracture surface of angular pin, therefore, impact toughness value was evaluated by V-notch Charpy impact test. It was confirmed that the impact absorption energy was high when was tempered at a high temperature for a long time, and the toughness was slightly increased. Also, 2-parameter Weibull statistical analysis was investigated in order to evaluate the reliability of the measured micro Vickers hardness values and absorbed energy. The micro Vickers hardness and absorbed energy well followed a two-parameter Weibull probability distribution, respectively. The reverse design against angular pin was proposed as possible by using test results.

• Nuclear Engineering and Technology
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• v.54 no.3
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• pp.817-825
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• 2022

A recent benchmarking effort, under the auspices of the Organization for Economic Cooperation and Development (OECD) Nuclear Energy Agency (NEA), has been made to evaluate the current state of modeling and simulation tools available to model fluoride salt-cooled high temperature reactors (FHRs). The FHR benchmarking effort considered in this work consists of several cases evaluating the neutronic parameters of a 2D prismatic FHR fuel assembly model using the participants' choice of simulation tools. Benchmark participants blindly submitted results for comparison with overall good agreement, except for some which significantly differed on cases utilizing a molybdenum-bearing control rod. Participants utilizing more recently updated explicit isotopic cross sections had consistent results, whereas those using elemental molybdenum cross sections observed reactivity differences on the order of thousands of pcm relative to their peers. Through a series of supporting tests, the authors attribute the differences as being nuclear data driven from using older legacy elemental molybdenum cross sections. Quantitative analysis is conducted on the control rod to identify spectral, reaction rate, and cross section phenomena responsible for the observed differences. Results confirm the observed differences are attributable to the use of elemental cross sections which overestimate the reaction rates in strong resonance channels.

• International Journal of Advanced Culture Technology
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• v.8 no.2
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• pp.159-164
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• 2020

The response analysis of frame structure with open section beams considering warping conditions and short duration load have been performed. When a beam of frame structure is subjected under torsional moment, the cross section will deform a warping as well as twist. For some thin-walled sections warping will be large, and accompanying warping restraint will induce axial and shear stresses and reduce the twist of beam which stiffens the beam in torsion. Because of impact or blast loads, the wave propagation effects become increasingly important as load duration decreases. This paper presents that a warping restraint in finite element model effects the behavior of beam deformation, dynamic mode shape and response analysis. The computer modelling of frame is discussed in linear beam element model and linear thin shell element model, also presents a correlation between computer predicted and actual experimental results for static deflection, natural frequencies and mode shapes of frame. A method to estimate the number of normal modes that are important is discussed.

• Journal of Korea Technology Innovation Society
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• v.7 no.2
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• pp.283-304
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• 2004

Evaluating the sources of economic output is obviously important, and numerous attempts have been made to judge the impact of many different factors on economic output. It is widely accepted that high-technology(HT) is one of the important factors in economic output. This paper empirically explores the impacts of HT exports on economic output using a cross-county analysis based on data from 89 countries for the year 1988-2000. To this end, several versions of the neoclassical growth models, explicitly including HT exports, are estimated. Subject to the appropriate caveats, the results provide further support for several key conclusions of the former studies - investment in physical capital, population growth, and the human capital are important in accounting fer economic output across countries. More importantly, it is concluded that HT exports significantly contribute to economic output. Interestingly, the conclusion is valid f3r developing countries, but not far developed countries.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.169.2-169.2
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• 2010

Recently, the massive offshore bridges in a ship passage have been constructed on the sea. Therefore, the ship impact protection for the bridge-piers are installed to consider the possibility of vessel collision danger. Due to the ship impact protection, the flow-field characteristics are changed in comparison with the condition without the ship impact protection. Especially, the fluid velocity between the pier and the ship impact protection is possible to increase due to the contraction of the cross sectional area of flow. In this study, the tidal energy magnitude around the ship impact protection of Incheon bridge is assessed by simulating the flow-field by using FLOW-3D software.

• Journal of the Korea Institute of Military Science and Technology
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• v.20 no.4
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• pp.467-473
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• 2017

In this paper, impact characteristics of a water entry gliding vehicle were analyzed using a finite element method. To guarantee the validity of analysis results, a convergence test was performed for several ratios of Euler and Largrange mesh sizes. The impact coefficient was calculated with respect to entry angles and angle of attacks. It can be observed that the impact coefficient was large at a high cross-section gradient and was also affected by cavitation. This study could be useful in the preliminary design stage of a water entry bomb development.

• 한국지구물리탐사학회:학술대회논문집
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• 2005.05a
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• pp.165-180
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• 2005

Impact seismic wave test is a method for nondestructive testing of concrete structure using of stress wave which is propagated and reflected from internal flaws within concrete structure and external surface, In this study, we performed non-destructive testing using impact seismic wave test for safety diagnosis of civil engineering structures. For this, I've compared and analized the result in the way of reflective method mostly using on one-dimension such as tunnel lining, and penetration method using the way of cross hole and tomography.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.4
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• pp.409-417
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• 2022

This research uses a panel data set of selected developed and emerging economies to investigate the relationship between firm value and the Islamic label. A low-debt company is a proxy for excellent governance, and good governance has a significant positive impact on a company's valuation. We can claim that the Islamic label may also be a proxy for excellent governance and will significantly impact a company's economic value because it reflects low debt Sharia-compliant companies. To explore this relationship, cross-country data from non-financial enterprises in Pakistan, the United States, Malaysia, and Indonesia was acquired from 2010 to 2015. The study's findings indicate that the Islamic label has a positive significant impact on the firm's worth in the whole sample, including all countries. With the exception of the United States, we have also collected the same information at the country level. We also discovered that the corporate governance index at the firm level has a positive significant impact on firm value. The findings show that the Islamic label reflects good governance and hence can be used as a proxy for good governance. The analysis differentiates between Islamic labeled and conventional enterprises in developed and emerging nations, adding to our understanding of who contributes to enhanced corporate financial performance.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.6
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• pp.80-87
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• 2020

The currently observed trend in car manufacturing is to increase energy-efficiency by producing lighter cars. This study examines the replacement of particular parts, specifically around the impact beam, with material composites 30% lighter than conventional steel currently used. The shape of the impact beam was determined as the trapezoidal cross-sectional area with central reinforcement, using three-point bending analysis. A prototype was fabricated based on the findings of our study and its performance was evaluated by the three-point bending analysis; 2 ply of aramid applied for its displacement. The performance of the final prototype for the door assembly was evaluated using a side-door strength test, which resulted to measured initial strength of 10.5 KN and intermediate strength of 15.6 KN. This research provides a promising solution for better impact beam manufacturing.

• Journal of Distribution Science
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• v.12 no.5
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• pp.15-26
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• 2014

Purpose - This study addresses an acquisition's impact on a firm's strategic relationship based on findings of existing academic studies and theoretical assertions. Through examining existing research results and theoretical grounds for an acquisition's impact on various stakeholders, this study indirectly approaches the impact on stakeholders including alliance partners. Research design, data, and methodology - This research identified a variety of related theoretical foundations and empirical studies. Research objectives of prior studies mainly focused on merging firms and direct participants of acquisition activity. In addition, academic attention on the impact on rival firms has recently been growing. However, little research on alliance partners was found. Prior studies simultaneously employed event study methodology and cross-sectional analysis to make further theoretical contributions. Results and Conclusions - Based on the findings of prior studies, this research proposed a complementary research model for future academic inquiry into the impact of an acquisition on an alliance partner's return and for predicting an acquisition announcement's effect on alliance partners.