• 한국경영과학회지
• /
• 제34권4호
• /
• pp.73-89
• /
• 2009

Circular shareholdings among three companies are formed when company A owns stock in company B, company B owns stock in company C, and company C owns stock in company A. Since circular shareholdings among large family-controlled firms are used to give the controlling shareholder greater control or more opportunities to expropriate minority investors, the government has encouraged large business groups to gradually remove their circular shareholdings. In this paper, we propose a combinatorial optimization model that can answer the question, which equity investments among complicated investment relationships of one large business group should be removed to resolve its circular shareholdings. To the best knowledge of the authors, our research is the first one that has approached the circular shareholding problem in respect of management science. The proposed combinatorial optimization model are formulated into integer programming problem and applied to some Korean major business groups.

• Journal of Trauma and Injury
• /
• 제34권1호
• /
• pp.66-69
• /
• 2021

When treating firearms injuries, knowledge of the proper management is important because these injuries have high morbidity and mortality. However, due to strict gun safety regulations, surgeons in Asia often have limited experiences with gunshot wound management. Recently, the authors had the experience of removing a bullet that did not cause hemopneumothorax, but remained in the lung parenchyma. Due to the risk of complications that could occur if the bullet was not removed, surgical treatment was eventually performed to remove the bullet. A literature review was needed to determine whether this treatment was appropriate. We concluded that removing the bullet could prevent incidental complications. In this regard, the authors report a case along with a review of the relevant literature to suggest appropriate treatment directions for surgeons who do not have experience with gunshot wounds.

• 한국보건간호학회지
• /
• 제36권1호
• /
• pp.47-58
• /
• 2022

Purpose: This study was undertaken to present an effective plan for the development of an educational program and a strategy to promote patient safety management activities for nursing students by identifying factors that affect these activities based on the theory of planned behavior. Methods: A self-report questionnaire was distributed to 300 nursing students who had clinical practice experience at three nursing colleges in Daejeon, Gyeongbuk, and Jeonbuk. The significance of the model fit, and the path effect was confirmed by confirmatory factor analysis. Results: The hypothetical model for patient safety management activities was appropriate. Among the 5 pathways, 4 were significant. It was found that behavioral intention had a direct influence on patient safety management activities, and perceived behavioral control and attitude had an influence on behavioral intention. Conclusion: To strengthen the perceived behavioral control of nursing students' patient safety management activities, it is necessary to analyze and remove obstacles and provide education that reflects the characteristics of the subject's health problems. In addition, through self-directed learning involving simulation practice, nursing students should be exposed to patient safety accidents, so that they can recognize the risks early and solve problems through critical thinking while bringing about the necessary changes in their attitude.

• 디지털융복합연구
• /
• 제11권7호
• /
• pp.135-140
• /
• 2013

잡음 추정과 검출 알고리즘에서는 LMS Filter를 이용하여 변화하는 잡음 환경에 빠르게 적응할 수 있도록 한다. 하지만 LMS Filter는 잡음 추정을 위한 일정 시간 동안 적응 시간이 필요하며 신호의 변화가 일어날 경우 더 많은 적응 시간이 소요되는 단점을 가지고 있다. 따라서 이를 보완하기 위하여 프레임 단위의 AELMS Filter를 이용한 잡음 제거 방법을 제안한다. 본 논문은 잡음 환경에서 입력되는 신호를 프레임 단위로 분할하고 평균과 분산을 이용한 예측 LMS Filter를 구성하여 잡음을 제거하므로 잡음 환경이 변화하더라도 빠른 적응 시간으로 잡음을 제거한다. 또한 환경 잡음과 음성 신호가 혼합되어 입력될 때 잡음을 제거하여 음성의 고유 특성을 유지하고 음성 정보 손상을 줄이기 위한 방법이다. 프레임 단위의 AELMS Filter를 이용한 잡음 제거 방법으로 잡음 제거 성능을 평가하였다. 실험 결과 변화하는 환경 잡음을 제거하여 얻은 감쇠도가 평균 6.8dB 향상되었다.

• Membrane and Water Treatment
• /
• 제13권5호
• /
• pp.227-233
• /
• 2022

The objective of the study, to develop adsorbent based purifier for removal of radiological and nuclear contaminants from contaminated water. In this regard, 3-aminopropyl silica functionalized with ethylenediamine tetraacetic acid (APS-EDTA) adsorbent prepared and characterized by Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD). Prepared APS-EDTA used for adsorptive studies of Cs(I), Co(II), Sr(II), Ni(II) and Cd(II) from contaminated water. The effect on adsorption of various parameters viz. contact time, initial concentration of metal ions and pH were also analyzed. The batch method has been employed using metal ions in solution from 1000-10000 ㎍/L, contact time 5-60 min., pH 4-10 and material quantities 50-200 mg at room temperature. The obtained adsorption data were used for drawing Freundlich and Langmuir isotherms model and both models were found suitable for explaining the metal ions adsorption on APS-EDTA. The adsorption data were followed pseudo second order reaction kinetics. The maximum adsorption capacity obtained 1.3037-1.4974 mg/g for above said metal ions. The results show that APS-EDTA have great potential to remove Cd(II), Co(II), Cs(I), Ni(II) and Sr(II) from aqueous solutions through chemisorption and physio-sorption.

• Safety and Health at Work
• /
• 제1권1호
• /
• pp.1-10
• /
• 2010

The Finnish risk assessment practice is based on the Occupational Safety and Health (OSH) Act aiming to improve working conditions in order maintain the employees' work ability, and to prevent occupational accidents and diseases. In practice there are hundreds of risk assessment methods in use. A simple method is used in small and medium sized enterprises and more complex risk evaluation methods in larger work places. Does the risk management function in the work places in Finland? According to our experience something more is needed. That is, understanding of common and company related benefits of risk management. The wider conclusion is that commitment for risk assessment in Finland is high enough. However, in those enterprises where OSH management was at an acceptable level or above it, there were also more varied and more successfully accomplished actions to remove or reduce the risks than in enterprises, where OSH management was in lower level. In risk assessment it is important to process active technical prevention and exact communication, increase work place attraction and increase job satisfaction and motivation. Investments in OSH are also good business. Low absenteeism due to illness or accidents increases directly the production results by improved quality and quantity of the product. In general Finnish studies have consistently shown that the return of an invested euro is three to seven-old. In national level, according to our calculations the savings could be even 20% of our gross national product.

• Corrosion Science and Technology
• /
• 제16권2호
• /
• pp.85-89
• /
• 2017

One of the most challenging issues in the oil and gas industry is corrosion assessment and management in subsea structures or equipment. At present, almost all steel pipelines are sensitive to corrosion in harsh working environments, particularly in salty water and sulphur ingress media. Nowadays, the most commonly practiced solution for a damaged steel pipe is to entirely remove the pipe, to remove only a localized damaged section and then replace it with a new one, or to cover it with a steel patch through welding, respectively. Numerous literatures have shown that fiber-reinforced polymer-based composites can be effectively used for steel pipe repairs. Considerable research has also been carried out on the repair of corroded and gouged pipes incorporated with hybrid natural fiber-reinforced composite wraps. Currently, further research in the field should focus on enhanced use of the lesser and highly explored hybrid-biocomposite material for the development in corrosion prevention. A hybrid-biocomposite material from renewable resource based derivatives is cost-effective, abundantly available, biodegradable, and an environmentally benign alternative for corrosion prevention. The aim of this article is to provide a comprehensive review and to bridge the gap by developing a new hybrid-biocomposite with superhydrophobic surfaces.

• 웰빙융합연구
• /
• 제6권3호
• /
• pp.33-36
• /
• 2023

Purpose: Since the food wastewater contains a high concentration of nitrogen, it is very important to find a way to efficiently remove it. Research design, data and methodology: A total of four experiments were conducted under different conditions to remove ammonia nitrogen present in the food wastewater. The experiment was designed by adding sodium hypochlorite to the raw food wastewater and varying conditions such as pH control, aeration/precipitation, and stirring. Results: The ammonia nitrogen removal rate in Experiment 1 was about 12% (sodium hypochlorite added), ammonia nitrogen increased about 4.7% in Experiment 2 (sodium hypochlorite added after aeration/precipitation in a bioreaction tank, stirring), and decreased about 52.5% (sodium hypochlorite added after controlling and stirring). Conclusions: When the concentration of sodium hypochlorite was high, ammonia nitrogen was best removed, and the pH was adjusted to 12, and sodium hypochlorite was added after stirring, and the removal was the second best. If the method of this study is further studied and developed, it can be basic data for ammonia nitrogen removal in the future.

• 한국통신학회논문지
• /
• 제42권3호
• /
• pp.623-638
• /
• 2017

클라우드(Cloud) 기술이 적용되는 영역은 기술의 발전과 서비스의 다양화로 점차 확대되고 있다. 방송 플랫폼에도 투자 효율화, 운영 효율화, 서비스 경쟁력 확보 등의 측면에서 클라우드 기술이 도입되고 있다. 최근 국내에서는 클라우드 방송 플랫폼이 UI와 서비스에 도입되면서 서비스 경쟁이 가속화 되고 있다. 클라우드 방송 기술은 단말기의 자원과 소프트웨어 구조에 종속성 없이 서비스를 제공하고, 단말기 별로 분리되어 관리되고 있던 UI와 서비스를 서버기반으로 통합하여 운영될 수 있도록 한다. 논문에서는 클라우드 방송 플랫폼에 대해서 설명하고 적용 효과에 대해서 설명한다.

• 품질경영학회지
• /
• 제46권4호
• /
• pp.911-922
• /
• 2018

Purpose: This study provides an overview of the Product Liability Act which was revised in 2017 and took effect in 2018. It analyzes the effects of the revised Act on corporate management from internal and external perspectives to present coping strategies so that companies can synthetically respond to such effects. Methods: In order to achieve the purpose of this study, experts like companies, academia, governmental institutions, and consultants were invited, and Delphi techniques were applied to derive means, standard deviations, and Content Validity Ratio. Results: In this study, based on two expert questionnaire surveys, strengths and weaknesses of the internal environment of companies and opportunities and threats of the external environment were derived, followed by provision of S/O, W/O, S/T, and W/T strategies. Conclusion: To fundamentally remove the causes of accidents on their products, the relevant companies should strengthen the activities to increase product safety. They shall cooperate with suppliers to arrange the measures to speedily secure safety of consumers.