• Journal of Mechanical Science and Technology
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• 제18권2호
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• pp.193-202
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• 2004

This paper presents a computer method for the dynamic analysis of a system of rigid bodies in plane motion. The formulation rests upon the idea of replacing a rigid body by a dynamically equivalent constrained system of particles. Newton's second law is applied to study the motion of the resulting system of particles without introducing any rotational coordinates. A velocity transformation is used to transform the equations of motion to a reduced set. For an open-chain, this process automatically eliminates all of the non-working constraint forces and leads to an efficient integration of the equations of motion. For a closed-chain, suitable joints should be cut and few cut-joints constraint equations should be included. An example of a closed-chain is used to demonstrate the generality and efficiency of the proposed method.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2010년도 제39회 하계학술대회 초록집
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• pp.56-56
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• 2010

Using first-principles density-functional theory calculations, we find dramatically different electronic states in the C chains generated on the H-terminated C(111) surface, depending on their length and parity. The infinitely long chain has $\pi$ electrons completely delocalized over the chain, yielding an equal C-C bond length. As the chain length becomes finite, such delocalized $\pi$ electrons are transformed into localized ones. As a result, even-numbered chains exhibit a strong charge-lattice coupling, leading to a bond-alternated structure, while odd-numbered chains show a ferrimagnetic spin ordering with a solitonlike structure. These geometric and electronic features of infinitely and finitely long chains are analogous to those of the closed (benzene) and open (polyacetylene) chains of hydrocarbons, respectively.

• 대한수학회보
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• 제59권2호
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• pp.319-343
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• 2022

We discuss the notions of positive expansivity, chain transitivity, uniform rigidity, chain mixing, weak specification, and pseudo orbital specification in terms of finite open covers for Hausdorff topological spaces and entourages for uniform spaces. We show that the two definitions for each notion are equivalent in compact Hausdorff spaces and further they are equivalent to their standard definitions in compact metric spaces. We show that a homeomorphism on a Hausdorff uniform space has uniform h-shadowing if and only if it has uniform shadowing and its inverse is uniformly equicontinuous. We also show that a Hausdorff positively expansive system with a Hausdorff shadowing property has Hausdorff h-shadowing.

• 대한수학회보
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• 제40권4호
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• pp.671-675
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• 2003

The object of the present paper is to give an univalence condition for analytic functions in the open unit disk U by using the properties for subordination chains.

• 한국엔터테인먼트산업학회논문지
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• 제14권8호
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• pp.391-396
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• 2020

본 연구는 하지 사슬운동 유형이 라이프케어먼트를 위한 운동 수행능력에 미치는 영향을 알아보고자 하였다. 이를 위해 전라북도 소재 J대학의 정상 성인 여성 20명이 참여하여 두 가지 유형의 사슬운동을 적용하여 배곧은근의 활성도와 균형 능력에 대한 운동 효과 차이를 검사하였다. 참여자들은 각 유형의 운동에 대해 4주 동안 운동을 시행하도록 하였고 그룹 내 및 그룹 간 차이를 비교하기 위해 대응표본 t-검정과 독립 표본 t- 검정을 이용해 분석하였다. 연구 결과, 근육활성도와 균형 기능에서 닫힌사슬 운동이 열린사슬 운동보다 더 효과적이라는 것을 알 수 있었다. 따라서 임상 치료 환경에서 환자에게 하지 운동기능 향상을 위해 사슬운동을 적용할 경우에 닫힌사슬 운동 적용이 보다 효과적일 수 있음을 제시한다.

• Journal of Microbiology
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• 제35권1호
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• pp.40-46
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• 1997

The pWHM220 cosmid with a 24-kb insert cloned from Streptomyces albus ATCC 21838 induces the biosynthesis of a polysther antibiotic similar to salinomycin in Streptomyces invidans. We have analyzed this region by DNA sequencing as well as Southern blot hybridization with type I and type II polyketide synthase (PKS) probes. Surprisingly, we found another set of type II SKS genes only 10-kb from the original PKS genes, salABCDE. The DNA sequence revealed two complete open reading frames (ORFs) named salB2 and salC2, and one partial ORF that does not resemble any known DNA or deduced protein sequence. The salC2 should code for chain length determining factor while the deduced amino acid sequence encoded by salB2 exhibits high similarity to .betha.-ketoacyl synthase from different PKS gene clusters. The highest identity was found for .betha.-keetoacyl synthases from S. argillaceus (MtmP. 59.1% identity), the mithramycin producer and from S. venezuelae ISP5230 (JadA, 52.3% identity), the jadomycin producer. The SalC2 protein clearly resembles its counterparts in order aromatic PKS gene clusters that are believed to influence the length of the polyketide chain. The highest identities observed were to that of S. argillaceus (MtmK, 62.3%) and S. venezuelae ISP 5230 (JadB, 55.1%) proteins, Moreover, the deduced amino acid sequences of the salB2 and salC2 products were 29.0% identical.

• 스마트미디어저널
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• 제8권2호
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• pp.94-98
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• 2019

본 논문에서는 관리자가 자신이 소유하고 있는 IoT 시스템을 관리할 수 있도록 하는 도구를 개발한다. 장비 에이전트는 오픈소스 블록체인 프레임워크 기반으로 구성해 데이터의 불변성을 보장하고, 장비에 연결된 AP에 대한 추적성을 확보하여 자산에 대한 위치를 파악할 수 있다. 관리자는 블록체인 장부에서 장비의 연결 내역을 추적할 수 있다. 추가로 네트워크 형성 과정 중 발생하는 ARP 프로토콜의 ARP 추가 요청에 대한 신뢰를 없애 ARP poisoning 공격을 방지할 수 있는 가능성에 대해 연구한다.

• 대한화학회지
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• 제36권5호
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• pp.770-779
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• 1992

$Fe(CO)_5와 알킨일리튬의 반응에서 생성된 아실 음이온 착물을 CH_3CH_2OSO_2F로 처리하는 방법으로 5종의 철 알킨일카르벤 착물 유도체(1)들을 합성하였다. [R-C≡C-C(OCH_2CH_3)]Fe(CO)_4(R = n-프로필, 시클로헥실, t-부틸, 트리메틸실릴, 페닐). 트리메틸시릴기가 치환된 유도체(1d)와 8종의 열린 고리 1,3-디엔과의 반응에서 {\eta}^3-비닐카르벤 착물 유도체(2)를 주생성물로 얻었다.$

• 대한통합의학회지
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• 제1권2호
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• pp.67-80
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• 2013

Purpose : This study was to investigate effects of closed kinetic chain and open kinetic chain exercise on the lumbar stabilizarion. Methods : A total of 30 healthy over 20 years old college students(men = 14, women = 16) who were participated in this. We selected randomly people of CKC, OKC, and control group. For the past four weeks, CKC and OKC group worked out 3 times per week and then we compared within group and between groups on muscle width. Results : 1. The width of internal oblique, transverse abdominis, and multifidus were all significantly increased after four weeks exercise in the CKC group(P<.05). 2. The width of internal oblique, transverse abdominis, and multifidus were all increased after four weeks exercise in the OKC group but transverse abdominis musule only showed significant difference. 3. Difference values between pre-exercise and post-exercise of transverse abdominis and multifidus in the CKC group was significantly high and difference among the groups were significant. Conclusion : Accordingly, lumbar stabilizing exercise was more effective to increase a width of abdominal deep muscles through CKC exercise.

• Asian-Australasian Journal of Animal Sciences
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• 제18권8호
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• pp.1188-1193
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• 2005

An investigation was carried out to study the effect of two housing systems on physiological responses and energy expenditure of sheep in a semi-arid region of India. Two types of housing management were adopted. First was a shed- $6{\times}3\;m^2$ structure with all the four sides of 1.8 m chain link fencing with a central height of 3 m. The roof was covered with asbestos sheets and with mud floorings. Second was an open corral- $6{\times}3\;m^2$ open space with all the four sides covered with 1.8 m chain link fencing. Thirty-four (32 ewes and 2 rams) sheep of native Malpura breed aged about 18 months (body weight 28 kg ewes; 35 kg rams) were grazed together on a 35 ha plot of native range. All the sheep were grazed as a flock from 08.00 to 17.00 h during a yearlong study. The flock was divided into two groups (16 ewes+1 ram) in the evening and housed as per the systems (Shed and Open Corral). Dry and wet temperatures were recorded at 06.00 h and 21.00 h using a wet and dry bulb-thermometer both inside the shed and in the open corral and temperature humidity index (THI) was calculated. There was significant (p<0.05) difference in the THI between shed and open corral in all the seasons, indicating that shed was always warmer compared to open corral. Rectal temperature (RT) of both the groups of sheep was similar during morning as well as evening throughout the seasons. There were significant (p<0.05) differences in the skin temperature (ST) and respiration rate (RR) between the two groups at both the measurements in all the seasons. Highest energy expenditure (EE) was recorded inside the shed at 21.00 h (224 kJ/h) during monsoon and lowest at 6.00 h during winter (119 kJ/h). There was a significant (p<0.05) difference between the EE inside the shed and that in the open corral. It was concluded that housing had significant effects on the physiological responses and EE of sheep. Provision of housing at night was stressful during monsoon (with less rainfall) and summer, whereas it was protecting the sheep from acute cold during winter in a semi-arid region of India.