• Bulletin of the Korean Chemical Society
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• 제19권11호
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• pp.1161-1164
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• 1998

The catalytic transformation of sterically bulky tertiary stannane n-Bu3SnH by the Cp2MCl2/Red-Al (M=Ti, Zr, Hf) and M(CO)6 (M=Cr, Mo, W) catalysts yielded two kinds of catenated products: one is a cross-linked polystannane as minor product, and the other is hexabutyldistannane (n-Bu3Sn)2 as major product. The distannane was produced by simple dehydrocoupling of n-Bu3SnH, whereas the cross-linked polystannane could be obtained via redistribution/dehydrocoupling combination process of n-Bu3SnH. The redistribution/dehydrocoupling combination process may initially produce a low-molecular-weight oligostannane with partial backbone Sn-H bonds which could then undergo an extensive cross-linking reaction of backbone Sn-H bonds, resulting in the formation of an insoluble polystannane.

• 대한전자공학회논문지
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• 제26권8호
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• pp.1247-1256
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• 1989

In this paper, we propose the dynamic scene segmentation algorithm using a cross mask and edge information. This method, a combination of the conventioanl feature-based and pixel-based approaches, uses edges as features and determines moving pixels, with a cross mask centered on each edge pixel, by computing similarity measure between two consecutive image frames. With simple calcualtion the proposed method works well for image consisting of complex background or several moving objects. Also this method works satisfactorily in case of rotaitional motion.

• Macromolecular Research
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• 제17권11호
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• pp.926-930
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• 2009

A new method for encapsulating nanomaterials within intermediary layer cross-linked (ILCL) polymeric micelles using a bifunctional photo-cross-linking agent was developed. For ILCL polymeric micelles, an amphiphilic triblock copolymer of poly(ethylene glycol)-b-poly(2-hydroxyethyl methacrylate)-b-poly(methyl methacrylate) (PEG-PHEMA-PMMA) was synthesized via consecutive atom transfer radical polymerization (ATRP), Di(4-hydroxyl benzophenone) dodecanedioate (BPD) was used as a bifunctional photo-cross-linking agent. The PMMA-tethered Au nanoparticles and BPD, or pyrene and BPD were encapsulated in the PEG-PHEMA-PMMA micelles, and their intermediary layers were photo-cross-linked by UV irradiation for 1 h. The HEMA units donated labile hydrogens to the excited-state benzophenone groups in BPD, and they were subsequently cross-linked by BPD through radical-radical combination. The spherical structures of the PEG-PHEMA-PMMA micelles containing the Au nanoparticles or pyrene were unaffected by the photo-cross-linking process.

• 통합자연과학논문집
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• 제4권3호
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• pp.177-181
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• 2011

The catalytic dehydrocoupling of bis(1-sila-3-butyl)benzene 1 and 2-phenyl-1,3-disilapropane 2 by $Cp_2ZrCl_2$/Red-Al and $Cp_2ZrCl_2$/n-BuLi was reported to compare their catalytic efficiency. The dehydrocoupling of monomeric silanes 1 with the $Cp_2ZrCl_2$/Red-Al and $Cp_2ZrCl_2$/n-BuLi combination catalysts produced two phases of polymers: one is a highly cross-linked insoluble solid, and the other is noncross-linked or slightly cross-linked soluble oil and could be a precursor for the solid polymer. The dehydrocoupling of 2 with the $Cp_2ZrCl_2$/n-BuLi combination catalyst similarly produced two phases of polymers. By contrast, the catalytic reaction of 2 with the $Cp_2ZrCl_2$/Red-Al combination catalyst produced a soluble polymer via redistribution/dehydrocoupling process.

• 한국정밀공학회지
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• 제19권10호
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• pp.84-91
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• 2002

The shaft with the circular cross section have symmetric structural combination parts to keep the rotating balance. Hence the crack usually emanate from symmetric combination parts due to the stress concentration of these parts. In this study to estimate the fatigue behavior of symmetric cracks, the fatigue test was performed by using rotary bending tester and the specimen with symmetric defects in circular cross section. From the facts the characteristics of crack initiation and propagation on the symmetric surface cracks in circular cross section was examined. Also we observed the internal crack using oxidation coloring and investigated the fatigue behavior using the relationship between surface crack and internal crack. As a result of fatigue lift of symmetric cracks was reduced to 35% compared to single crack’s. We examined the characteristics of fatigue behavior in element with symmetric cracks using internal crack propagation rate and maximum stress intensity factor range obtained from approximation method.

• International Journal of Precision Engineering and Manufacturing
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• 제5권4호
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• pp.36-42
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• 2004

The shaft with the circular cross section has symmetric structural combination parts to keep the rotating balance. Hence the crack usually initiates from symmetric combination parts due to the stress concentration of these parts. In this study to estimate the fatigue behavior of symmetric cracks, the fatigue test was performed by using a rotary bending tester and the specimen with symmetric defects in circular cross section. The characteristics of crack initiation and propagation on the symmetric surface cracks in circular cross section were examined. We also observed the internal crack using the oxidation coloring method and investigated the fatigue behavior using the relationship between the surface crack and the internal crack. As a result, the fatigue life of symmetric cracks was reduced by 35% compared to that of a single crack. We examined the characteristics of fatigue behavior of elements with symmetric cracks using internal crack propagation rate and maximum stress intensity factor range that were obtained from an approximation method.

• Journal of Acupuncture Research
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• 제26권6호
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• pp.121-132
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• 2009

Objectives : To evaluate the current status of East-West combination treatment in joint disorders. Methods : The medical records of patients who visited the Joints & Rheumatism Center at the Kyung Hee East-West Neo Medical Center from April 2006 to June 2009 were evaluated. The general characteristics of patients who underwent combination treatment, trend in number of cross-system referrals, and disorders and involved body regions of patients referred to the Eastern medical hospital from the Western medical hospital were initially assessed. 6 major disorders were found from the initial scanning. The trend in number of cross-hospital referrals, number of visits to the Eastern medical hospital, current status of combination treatment, treatment modality, and reason for cross-system referral was evaluated. Results : 1. 1510 patients were referred from the Eastern medical hospital to the Western medical hospital, and 1065 patients were referred from the Western medical hospital to the Eastern medical hospital. First visit patients reached a peak at the second quarter of 2007 and fourth quarter of 2006 respectively, and have steadily decreased from then on. Referrals of female patients were twice as common as male patient referrals. Patients in their sixth or seventh decade of life were most commonly referred, and more outpatients were referred compared to inpatients. 2. Patients with knee joint disorders were most commonly referred from the Western medical hospital to the Eastern medical hospital, followed by hip, shoulder, ankle, wrist, and elbow joint disorders. The most common disorders for each of the above regions in referred patients were knee osteoarthritis, avascular necrosis of the hip, adhesive capsulitis, and ankle strain and sprain. The generalized disorders rheumatoid arthritis and ankylosing spondylitis followed. 3. Patients referred to the Eastern hospital received approximately 3 to 10 Eastern medical treatment sessions. 45 percent remained on constant combination treatment, and 98 percent of referred patients received acupuncture treatment. Conclusions : In regard to the number of patients and duration of combination treatment, combination treatment was successfully performed for knee osteoarthritis, rheumatoid arthritis, and ankylosing spondylitis, while it was not so for avascular necrosis of the hip, adhesive capsulitis, and ankle strain and sprain. Further research on this subject is required.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회/대한산업공학회 1999년도 춘계공동학술대회:정보화시대의 지식경영
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• pp.316-317
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• 1999

• 한국음향학회지
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• 제32권5호
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• pp.438-445
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• 2013

본 논문은 일본어 음성인식기 신규 개발을 위해 초기에 부족한 일본어 음성데이터를 보완하는 방법이다. 일본어 발음과 한국어 발음이 유사한 특성을 근거로 한국어 음성 데이터를 이용한 일본어 음향모델 성능개선 방법에 대하여 기술하였다. 이종언어 간 음성 데이터를 섞어서 훈련하는 방법인 Cross-Language Transfer, Cross-Language Adaptation, Data Pooling Approach등 방법을 설명하고, 각 방법들의 시뮬레이션을 통해 현재 보유하고 있는 일본어 음성데이터 양에 적절한 방법을 선정하였다. 기존의 방법들은 훈련용 음성데이터가 크게 부족한 환경에서의 효과는 검증되었으나, 목적 언어의 데이터가 어느 정도 확보된 상태에서는 성능 개선 효과가 미비하였다. 그러나 Data Pooling Approach의 훈련과정 중 Tyied-List를 목적 언어로만으로 구성 하였을 때, ERR(Error Reduction Rate)이 12.8 %로 성능이 향상됨을 확인하였다.

• International Journal of Aeronautical and Space Sciences
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• 제1권2호
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• pp.9-16
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• 2000

For aerodynamic design of missile bodies of non-circular cross-section, the combination of the slender body theory and the cross-flow analogy can hardly be applied owing to the lack of experimental data. An alternative is to utilize the Euler solution in the design stage. For enhanced accuracy, however, an adequate viscous correction is necessary to the Euler solution. In this work, such a procedure is examined to compensate the viscous effect by utilizing the concept of proportionality factor in cross-flow analogy. Predictions of aerodynamic coefficients combining the Euler solution and the viscous correction via proportionality factor are made for a missile body of elliptic cross-section. Results indicate that the present approach can be adopted in designing missile bodies of non-circular cross-sections.