• 제목/요약/키워드: TS imbalance

검색결과 6건 처리시간 0.02초

Kinetics and Mechanism of the Addition of Anilines to β-Nitrostilbenes in Acetonitrile

  • Sung, Dae-Dong;Kang, Sang-Soo;Lee, Jong-Pal;Jung, Dae-Il;Ryu, Zoon-Ha;Lee, Ik-Choon
    • Bulletin of the Korean Chemical Society
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    • 제28권10호
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    • pp.1670-1674
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    • 2007
  • Addition reactions of anilines (XC6H4NH2) to β-nitrostilbene (YC6H4CH=C(NO2)C6H4Y') have been investigated in acetonitrile at 30.0 oC. The magnitude of βX values (=0.11-0.34) indicates relatively earlier transition state for additions with anilines than with benzylamines. The signs of ρY and ρY' are positive with Δρ = ρY?ρY' = 0.04, demonstrating a TS imbalance with a negative charge development on the Cβ in the TS. The signs of cross-interaction constants ρXY (<0), ρXY' (<0) and ρYY' (>0) are consistent with bond forming and breaking processes. The relatively weak normal kinetic isotope effects involving deutarated nucleophiles, kH/kD>1, suggest an early, hydrogen-bonded, 4-member cyclic TS.

드럼 세탁기 탈수시 가속도 피드백 제어 (Direct acceleration feedback control of a washing machine during spinning process)

  • 이진원;스즈키 세이치로;선희복
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 추계학술대회
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    • pp.1642-1647
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    • 2003
  • The market of the horizontal axis washing machine (drum washing machine) has been growing drastically in Korea by about 80% annually since 2000. As market grows fast, the customerTs demands concerning quality becomes more strict and various. Imbalance sensing is a key technology to reduce the NVH problem in a washing machine, because the laundry is time-variant and uncontrollable source of imbalance, which can cause more than 200kgf exciting force. In this paper, imbalance-sensing methods are briefly reviewed, new acceleration sensing circuits are examined, and finally the control algorithm of spinning process is proposed and validated.

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뇌종양 분할을 위한 3D 이중 융합 주의 네트워크 (3D Dual-Fusion Attention Network for Brain Tumor Segmentation)

  • ;;;김수형
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2023년도 춘계학술발표대회
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    • pp.496-498
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    • 2023
  • Brain tumor segmentation problem has challenges in the tumor diversity of location, imbalance, and morphology. Attention mechanisms have recently been used widely to tackle medical segmentation problems efficiently by focusing on essential regions. In contrast, the fusion approaches enhance performance by merging mutual benefits from many models. In this study, we proposed a 3D dual fusion attention network to combine the advantages of fusion approaches and attention mechanisms by residual self-attention and local blocks. Compared to fusion approaches and related works, our proposed method has shown promising results on the BraTS 2018 dataset.

이산시간 Q 매개변수화 제어를 이용한 자기축수 시스템에 대한 부상과 불평형보정의 실험적 평가 (Experimental Evaluation of Levitation and Imbalance Compensation for the Magnetic Bearing System Using Discrete Time Q-Parameterization Control)

  • 이준호;;이기서
    • 소음진동
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    • 제8권5호
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    • pp.964-973
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    • 1998
  • 본 논문에서 자기 축수 시스템의 부상과 불평형 보상 제어기를 제안한다. 특정한 동작속도에서 불균형 진동과 부상을 제어하기위해 우리는 이산시간 Q 매개변수화 제어를 사용한다. 회전자의 속도가 p=0일 때, 회전소도와 같은 주파수로 회전자의 불균형은 없다. 그래서 부상을 만들기 위해 우리는 제어기가 z=1의 단위원에서 극점을 가지는 Q매개변수화 Q를 선택한다. 그러나 회전자의 속도가 p$\neq$0일 때, 회전속도와 같은 주파수로 정현파의 외란이 존재하게 된다. 그래서 이 외란의 점근적인 소멸을 하기위해 Q 매개화변수 제어기 자유 변수 Q가 제어기가 어떠한 회전속도 p에 대한 z=expjpTs에 있는 단위 원에서 극점을 가지도록 선택된다. 첫째로, 우리는 이 연구에서 적용된 실험적인 구성을 소개한다. 두 번째로, 우리는 차분 방정식의 형태로 자기축수 시스템의 수학적인 모델을 제안한다. 세 번째로 우리는 제안된 이산 시간 Q매개변수화 제어기 설계방법을 설명한다. 제어기의 자유 매개변수 Q는 안정한 전달함수가 된다고 가정한다. 네 번째로, 우리는 설계목적을 만족하는 자유 매개변수가 복잡한 최적문제를 풀기보다는 선형 방정식을 구함으로서 만족될 수 있다. 마지막으로 몇 개의 시뮬레이션과 실험적인 결과가 제언된 제어기를 평가하기 위해 구해진다. 획득된 결과는 회전설계 속도에서의 불균형 진동을 제어하는 제안된 제어기의 효과를 나타낸다.

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The Role of Universities in Research and Development and Technical Services (R & D & TS) in Korea

  • Kim, Sheung-Kown
    • 산업공학
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    • 제2권1호
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    • pp.79-96
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    • 1989
  • Abundant hard-working and well-educated human resources were the important sources of the spectacular economic success during the last decades. In contrast to the past sources of economic growth during the 1970's when labor and capital along with economies of scale were the dominant factors (the university has played an important role in the national economic success by supplying quality labour and intellectual talent.), the level of science, technological innovation and capital inputs will be of vital importance for future economic growth in Korea. The balance of payments in technology transfer together with the current state of R & D activities has been reviewed and some of the issues and problems underlying the university system that tend to hinder research in collaboration with research institutes and industries have been outlined. Serious imbalance in the allocation of research funds among research sectors was identified as the most serious problem to be fixed. The importance of science and technology education in private universities for the enhancement of the national level of science and technology has been re-examined. Also research and development in engineering and technical services has been emphasized. In conclusion, ways to bolster the role of universities in the research environment in cooperation with industry and research institutes have been suggested.

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이제마(李濟馬)와 장종정(張從正)의 학술사상(學術思想)에 대한 비교(比較) 연구(硏究) (A Comparative Study on the Theory of Lee jaema and Chang ts' ungcheng)

  • 최의권;김경요
    • 사상체질의학회지
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    • 제8권2호
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    • pp.41-68
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    • 1996
  • This thesis is a try for examining the historical characteristics of Constiutional medicine. For this purpose, I have examined their theory, and made a comparison carefully. Through this study, I have obtained several results as following. Both Chang and Lee lived in the time of change, which was unstable and uncertain. Under the condition, they both rejected following the existing trends of learned circles, and developed new thoughts and clinical techniques. They rejected superstitious beliefs and fatalism, and conducted the pursuit of experimental knowledge and rationale idea. Clinical experience was the very base of their study. They both criticized the bad habits of abuse of tonifing medication and health seeking. Especially Lee regarded control of emotion and regulation of a way of life as the best way for preservation of one's health. Chang regarded pathogenic factors as the ultimate factor of diseases, and strived for eliminating pathogenic factors, but L brought to a conclusion that the final factor of diseases was what is called "heart" itself, and emotional changes were the most essential causes of disease. It can be said that the pathogenesis insisted by Chang can be called The insistence that pathologic factors are the very etiology of all the disease (邪氣致病論), or all the diseases result from pathologic factors. And his whole remedy can be summarized as following, A study on the method of eliminating pathogenic factors. But the purpose of Constitutional medicine is to correct imbalance intrinsic to one's internal organs. In this aspect, Constitutional medicine is a "regulatory medicine". Depending on the classification of six vital substances, Chang classified all disease into six categories. These were based on symptoms and sings represented. While classification of diseases made by Lee was likely to rely upon constitutional characteristics. Chang thought that the three remedies made up of perspiration, purgation, vomiting were the most efficient way of eliminating pathogenic factors. Lee, however, thought those weren't methods of eliminating pathogenic factors but the best ways restoring one's self-regulation power. Chang thought that all the febrile disease essentially has a tendency in properties to belong to "heat", but Lee pointed out that pathologic processes are variable in accordance with constitutional features. They both regarded pathogenesis of diabetes as fire. That is to say, fire is the most essential factor of diabetes. And there are many risk factors such as inappropriate foods, drugs, climate, etc., but Lee thought what is most important is heart. Putting all accounts together, medical characteristics of Chang are similar to those of T aiyinjen and Shaoyangjen, and have no relation to those of those of Shaoyinjen. Therefore we can conclude that Chang understood pathologic processes of disease of T aiyinjen and Shaoyangjen, whether he knew about constitutional features or not.

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