• Bulletin of the Korean Chemical Society
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• v.25 no.1
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• pp.90-96
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• 2004

The conformations of dicyclopropyl, isopropyl cyclopropyl, and diisopropylcarbenes were optimized using density functional theory (B3LYP/6-31G(d)). We showed that the optimized geometries of carbenes with cyclopropyl groups are fully in accord with those expected for bisected W-shaped conformations, in which the effective hyperconjugation of a cyclopropyl group with singlet carbene can occur. The stabilization energies were evaluated at the B3LYP/6-311+G(3df, 2p)//B3LYP/6-31G(d) + ZPE level using an isodesmic equation. The relative stability of carbenes is in the order $(c-Pr)_2$C: > (i-Pr)(c-Pr)C: > $(i-Pr)_2$C:, and a cyclopropyl group stabilizes carbene more than an isopropyl group by nearly 9 kcal/mol. Energies for the decomposition of diazo compounds to carbenes increase in the order $(c-Pr)_2$ < (i-Pr)(c-Pr) < $(i-Pr)_2$ by ~9 kcal/mol each. From a singlettriplet energy gap ($E_{ST}$) calculation, the singlet level is lower than the triplet level and the $E_{ST}$ shows a trend similar to the stabilization energy calculations. For comparison, the optimized geometries and stabilization energies for the corresponding carbocations were also studied at the same level of calculation. The greater changes in geometries and the higher stabilization energies for carbocations compared to carbenes can explain the greater hyperconjugation effect.

• Journal of the military operations research society of Korea
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• v.6 no.2
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• pp.27-46
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• 1980

Computer model for calculating the maximum detection range of the pulse radar used for surface surveillance is developed, and the detailed procedures of each theoretical step are discussed. The quantity of radar antenna's receiving energy, transmitting energy and noise level are compared in this model. All the calculation steps are programmed in BASIC language. Finally, I have found the output of this model well matched with the some experimental results.

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.38-40
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• 2000

In this paper we propose a calculation method for fuzzy control based on quantized $\alpha$-cut decomposition of fuzzy sets. This method is easy to be implemented in analog hardware. The effect of quantization levels on defuzzified fuzzy inference results is investigated. A few quantization levels are sufficient for fuzzy control. The hardware implementation of this calculation method and the defuzzification by gravity center method by PWM are also presented.

• Computational Structural Engineering
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• v.10 no.3
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• pp.15-21
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• 1997

Modern ocean-going vessels are highly dynamically loaded all-welded structures. Traditionally, this fact has been taken into account in the design of ship structures by keeping the overall stress level within permissible limits and by limiting notch effects in the design of local structures. With an improving knowledge of loads and the rapid development of calculation means more detailed calculation-based methods are increasingly introduced. A brief review on fatigue assessment methods used in the design of ship structures has been given during the 1993 IIW International Conference in Glasgow. The rapid development during recent years underlines the importace of the subject and justifies its extended discussion in this paper.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10c
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• pp.319-321
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• 2004

최근 이더넷(Ethernet) 보급과 사용자의 증가 그리고 다양한 응용 서비스들의 등장으로 인하여 점차 네트워크 트래픽이 폭증하고 있다. 이에 따라서 SLA(Service Level Agreement)를 위한 대역폭 조절(Bandwidth의 Regulation)의 중요성은 더욱 높아지고 있다. 그러나 기존에 제시된 대역폭 조절 방식들은 이더넷에 적합하지 않거나 또는 너무 복잡하여, EFM(Ethernet for First Mile)에 적용하기 어려웠다. 그래서 본 논문에서는 이더넷에 적용하기 적합한 간단하면서도 효과적인 대역폭 조절(Bandwidth Regulation) 방법인 속도 계산(Rate Calculation)방식을 제안하며, 제안한 메커니즘에 대한 시뮬레이션을 통한 성능 분석을 수행하였다.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.10a
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• pp.149-152
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• 2008

The purpose of this study is to develop a control software for daylight responsive dimming systems and automated roller shading systems. Developed software in this study is to used determinate sky conditions, calculation of solar profile angle, control height of roller shade, calculation of dimming level(%) for daylight responsive dimming systems.

• Journal of the Korea Convergence Society
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• v.12 no.10
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• pp.137-144
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• 2021

The purpose of this study is to analyze the factors affecting the education experience, education needs, and knowledge level of calculation criteria for dental workers. It was conducted on dental workers in Daegu and Gyeongbuk province and an online survey was conducted using Google Survey. We used frequency analysis, crossover analysis, and ANOVA analysis method to find out general characteristic, education experience, education needs, and knowledge level according to education experience and education needs of candidates. As a result of in the knowledge level survey of dental health insurance, there were high rates of incorrect answers to the calculation criteria when the claim program automatically processes it or notifies you through an error window. The level of knowledge of candidates who are experienced, on a claim, and with experience in dental insurance training in the last six months was high. In conclusion, it seems that accurate and correct insurance claims are possible when the dental workers are familiar with the calculation criteria changed through regular dental health insurance education. We look forward to this study providing basic data in preparation of education system for professional dental insurance claims for dental workers.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.446-447
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• 2008

In this paper, a calculation method of the short-time emergency by considering a initial load level and overload time is presented. short-time emergency analyze transient thermal rating and Long-time emergency analyze steady-state thermal rating. Using the suggested method in the paper, increasing the short-term allowable current.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.1459-1464
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• 2006

In the previous studies on railway noise analysis, the main purpose of noise analysis is concerned with the reduction of A-weighted sound pressure level in order to satisfy noise regulations. However, more important facts on noise reduction are the subjective feelings of the human being on noise because people might be annoyed from the noise caused by train. In this paper, railway noise from different type of train are compared using the calculation of sound quality metrics with using strength related method that is calculation of A-weighted sound pressure level.

• Journal of Environmental Health Sciences
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• v.18 no.1
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• pp.47-57
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• 1992

This study was performed to evaluate contamination degree of heavy metals in sediments of Han River, compared with other nation's evaluation method. The results were as follows 1. The contamination Ratio calculation method by heavy metal concentration in differnt fraction size has a limitation to apply to all of the areas of Han river because of its characteristics of sediment. As a result, this method applied to only 4 areas of Pal Dang, Wang Sook Chon, Uk Chon, and Bul Kwang Chon, and Contmination Ratio of heavy metals in those areas were relatively low of below 3. So it's considered that those areas have less contaminated from anthropogenic contaminants. 2. The Contamination Ratio calculation method by heavy metal concentration in different areasthat of upper area to be background level-has a limitation also to apply to Han river. But it is considered that this method was relatively suitable to apply, so it should be prepared evaluation standand method for them. Contamination ratio from background level as Pal Dang area were most high in An Yang Chon. So it must be prepared purification and control measure at An Yang Chon.