• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.1
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• pp.12-20
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• 2006

Recently, new dispersed sources (DSG) such as Photovoltaic, Wind Power, fuel cell etc. are interconnected with distribution systems as national projects for alternative energy preparing for oil crisis. This paper deals with the optimal evaluation algorithms in the case where new dispersed sources are operated in distribution systems. It is very difficult and complicated to handle the interconnection issues for proper voltage managements, because professional skills and enormous amounts of data for the evaluations are required. The typical evaluation algorithms mainly depending on individual ability and quality of data acquired, inevitably cause the different results f3r the same issue, so unfair and subjective evaluations are unavoidable. In order to overcome these problems, this paper proposes reasonable and general algorithms based on the standard model system and proper criterion, which offers the fair and objective evaluations in any case.

• The Journal of Advanced Prosthodontics
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• v.13 no.3
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• pp.136-143
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• 2021

Purpose. This study aimed to evaluate the effect of repeated use of an implant handpiece under an implant placement torque (35 Ncm) and overloading torque condition (50 Ncm) on an output torque. Materials and Methods. Two types of implant handpiece systems (Surgicpro/X-DSG20L [NSK, Kanuma, Japan] and SIP20/CRB46LN [SAESHIN, Daegu, South Korea]) were used. The output torque was measured using a digital torque gauge. The height and angle (x, y, and z axes) of the digital torque gauge and implant handpiece were adjusted through a jig for passive connection. The experiment was conducted under the setting torque value of 35 Ncm (implant placement torque) and 50 Ncm (overloading torque condition) and 30 times per set; a total of 5 sets were performed (N = 150). For statistical analysis, the difference between the groups was analyzed using the Mann-Whitney U test and the Friedman test was used to confirm the change in output torque (α=.05). Results. NSK and SAESHIN implant handpieces showed significant differences in output torque results at the setting torques of 35 Ncm and 50 Ncm (P<.001). The type of implant handpiece and repeated use influenced the output torque (P<.001). Conclusion. There may be a difference between the setting torque and actual output torque due to repeated use, and the implant handpiece should be managed and repaired during long-term use. In addition, for successful implant results in dental clinics, the output torque of the implant handpiece system should be checked before implant placement.

• Nuclear Engineering and Technology
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• v.55 no.9
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• pp.3441-3449
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• 2023

We determined the radiation shielding properties for 10CaO-xPbO-(90-x) deteriorated silica gel (DSG) glass system (x = 20, 25, 30, 35, 40, and 45 mol.%). The mass attenuation coefficient (MAC) has been estimated at photon energies of 74.23, 97.12, 122, 662, 1173, and 1332 keV using a narrow beam X-ray attenuation and transmission experiment, the XCOM program, and a PHITS simulation. The obtained MAC values were applied to estimate the half value layer (HVL), mean free path (MFP), effective atomic number, and effective electron density. Results show that the MAC value of the studied glasses ranges between 0.0549 and 1.4415 cm²/g, increases with the amount of PbO, and decreases with increasing photon energy. The HVL and MFP values decrease with increasing PbO content and increase with increasing photon energy. The recycled glass, with the addition of PbO content (20-45 mol.%), exhibited excellent radiation shielding capabilities compared to standard barite and ferrite concretes and some glass systems. Moreover, the experimental radiation shielding parameters agree with the XCOM and PHITS values. This study suggests that this new waste-recycled glass is an effective and cost-saving candidate for X-ray and gamma-ray shielding applications.

• Journal of Distribution Science
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• v.13 no.2
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• pp.55-62
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• 2015

Purpose - This study aims to investigate the success factors pertaining to K-POPs from an analysis of the internal business environment. Much research has investigated Korean Moves or how to popularize them. The research mainly focused on aspects of Korean Moves. However, few studies have attempted to examine Korean Moves or K-POPs from a managerial viewpoint. The current research tries to investigate the success factors of K-POP from strategic perspectives, specifically utilizing internal resource based view perspectives. It differentiates itself by looking at the competitiveness of K-POP from the internal resources. Research design, data, and methodology - In the entertainment industry, where creativity is heavily stressed, competitiveness is often regarded within the organization as a form of intangible asset, knowledge, or technology that is often related with the organization's personnel. Some research has tried to reveal the competitiveness of K-POP using Porter's competitiveness of nations framework. Others utilize the adapted model of Porter's structure. However, these models only look at the outside environment, and not inside a firm's resource, knowledge, or capabilities. This research utilizes the VRIO model to examine the internal resources and capabilities of K-POP producers. The model measures whether a firm's internal resources and capabilities are valuable, rare, difficult to imitate by competitors, or organizable. The research covered businesses whose yearly revenue exceeds $10 Million in music planning and recording in South Korea. There were only thirteen such companies (one percent of the total population). Of these, companies for whom 20 percent or more of the sales revenue comes from the abroad are targeted. Only seven are selected and these participated in the research. In order to find a firm's internal resources, we conducted qualitative research methodology. Their business names and persons who participated in this research are not revealed due to case sensitive issues. Instead, we use unrelated initials for their names and their statements. Results - From the in-depth interview with top-tier K-POP producers and managers, the current research tried to identify resources and capabilities that helped to strengthen their competitiveness. These resources and capabilities are sought from the scope of the VRIO model, which looks at the internal resources and capabilities from the scope of value, rarity, imitability, and organization. Interviews with the top tier producers and managers reveal the internal success factors of K-POPs. We conclude that these resources and capabilities are from internally accumulated producing know-how, unique managing (training) system, and outstanding all-round entertainment capabilities of the performers. Conclusions - These results indicate that the core resources and capabilities of K-POP are robust. It will take a significant amount of time and money to imitate for followers, because these resources and capabilities are the result of time investment and are embedded into producers' and performers' know-how. Taking Luo (2000)'s argument, K-POP is in the second stage of the globalization process, which is configuring and allocation resource capabilities to a global scope.

• Korean Journal of Food Science and Technology
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• v.43 no.3
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• pp.375-380
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• 2011

This study was performed to investigate cholesterol improvement effects of adding fermented defatted soybean grit (FD) and FD added to 5 or 10% Corchorus olitorius (FDC). Cholesterol adsorption in the FD and FDC group was more than 70%. Apolipoprotein AI and CIII improved in HepG2 cells, and a greater improvement effect was shown in FDC than that in FD. We also investigated the effect of FDC on body lipid metabolism and a high-fat diet for 4 weeks. Rats were divided into control (Con), high-fat (HF), HF treated with 20% FD (HF-FD), and HF treated with 20% FDC (HF-FDC) groups. Plasma total cholesterol and low density lipoprotein-cholesterol concentrations, hepatic total cholesterol, and triglyceride contents were significantly lower in the HF-FDC group than those in the HF group. Additionally, fecal total cholesterol and triglyceride contents increased in rats treated with FDC. Hepatic 3-hydroxy-3-methylglutaryl-coenzyme A reductase activities were significantly lower in the HF-FDC group than those in the HF group.