• 대한기계학회논문집
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• 제19권4호
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• pp.1023-1032
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• 1995

The multiple cooperating robot system plays an important role in the research of modern manufacturing system as the emphasis of production automation is more on the side of flexibility than before. While the kinematic and dynamic analysis of a single robot is performed as an open-loop chain, the dynamic formulation of robot in a multiple cooperating robot system differs from that of a single robot when the multiple cooperating robots form a closed kinematic chain holding an object simultaneously. The object may be any type from a rigid body to a multi-joint linkage. The mobility of the system depends on the kinematic configuration of the closed kinematic chain formed by robots and object, which also decides the number of independent input parameters. Since the mobility is not the same as the number of robot joints, proper constraint condition is sought. The constraints may be such that : the number of active robot joints is kept the same as mobility, all robot joints are active and have interrelations between each joint forces/torques, two robots have master-slave relation, or so on. The dynamic formulation of system is obtained. The formulation is based on recursive dual-number screw-calculus Newton-Eulerian approach which has been used for single robot analysis. This new scheme is recursive and compact symbolically and may facilitate the consideration of the object in real time.

• 약학회지
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• 제22권4호
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• pp.233-237
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• 1978

We studied on the separation of $\alpha$- and $\beta$-chain globins, the conditions of paper electrophoresis and mobility of globins in paper electrophoresis to determine their chain anomaly. Acidic-acetone mothod of Wilson and Smith was found to be more effecient for separating $\alpha$- and $\beta$chain globions than trichloroacetic acid method of Hayashi. The conditions of paper electrophoresis were current of 20v/cm and 0.6mA/cm for three hours at room temperature. In paper electroporesis, the mobility of $\alpha$- -chain globin towards the cathode was greater than that of $\beta$-chain globin. The results showed tha tchain anomaly of $\alpha$- and $\beta$-chain globins can be determined by the method of paper electrophoresis.

• 산업공학
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• 제16권spc호
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• pp.21-27
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• 2003

Objective of this paper is to develop the user mobility model(UMM) which is used for the performance analysis of location update and paging algorithm and at the same time, consider the user mobility pattern(UMP) in zone-based cellular networks. User mobility pattern shows correlation in space and time. UMM should consider these correlations of UMP. K-dimensional Markov chain is presented as a UMM considering them where the states of Markov chain are defined as the current location area(LA) and the consecutive LAs visited in the path. Also, a new two dimensional Markov chain composed of current LA and time interval is presented. Simulation results show that the appropriate size of K in the former UMM is two and the latter UMM reflects the characteristic of UMP well and so is a good model for the analytic method to solve the performance of location update and paging algorithm.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.117.5-117
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• 2002

. Mobility analysis for overconstrained mechanisms is not clearly explained. . Aims at mobility analysis of overconstrained mechanisms . Representative screws is employed as a tool . A method to identifying the representative screw is introduced . Mobility analysis for several overconstrained parallel mechanisms and mobile robots

• Bulletin of the Korean Chemical Society
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• 제27권8호
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• pp.1154-1158
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• 2006

Anomalously high ionic mobilities of H+ and $OH^-$ are owing to the transfer of $H^+$ by the Grotthus chain mechanism. Molecular dynamics simulations for the system of 215 water including $OH^-$ ion at 298.15 K using the OSS2 model [J. Chem. Phys. 109, 5547 (1998)] as a dissociable water model with the use of Ewald summation were carried out in order to study the dynamics of $OH^-$ in water. The calculated ionic mobility of $OH^-$ is in good agreement with the experimental result and the Grotthus chain mechanism is fully understood.

• Macromolecular Research
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• 제14권6호
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• pp.630-633
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• 2006

In heterojunction photovoltaic devices of $ITO/TiO_2/poly$(3-alkylthiophene)/Au, the photo current was characterized at different temperatures for different alkyl chain lengths and regioregularities: regiorandom, regioregular poly(3-hexylthiophene), and regioregular poly(3-dodecylthiophene). The regioregularity and alkyl chain length affected the photovoltaic characteristics due to differences in hole-carrier transportation. The drift charge mobilities of these devices were analyzed by the space-charge-limited current theory using the relation between the dark current and the bias voltage. The photocurrent in the devices based on poly(3-alkylthiophene)s decreased rapidly below the temperature at which the drift charge mobility was $10^{-5}\;cm^2/V{\cdot}s$.

• 폴리머
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• 제24권1호
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• pp.23-28
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• 2000

Solvent 용접에 따른 무정형 고분자 폴리스티렌/폴리스티렌 계면의 접착강도의 변화를 butt joint실험을 통하여 살펴보았다. 폴리스티렌과 용해도 상수가 유사한 용매를 계면에 코팅함으로써 계면 분자쇄의 유동성 증가와 계면의 거침정도의 변화에 따른 접촉표면의 증가로 인하여 접착 강도가 증가함을 확인하였다. 사용용매의 비등점이 접착온도보다 높은 경우, 접착강도의 증가는 용매에 의한 분자쇄의 유동성 증가에 기인되는 반면 용매의 비등점이 접착온도에 비해 낮을 경우 접착강도의 증가는 용매에 의한 접촉표면의 증가에 의존함을 알 수 있었다. 접착온도가 높을수록, 접착시간이 길어질수록 접착강도는 증가되며, 사용용매가 접착강도에 미치는 영향은 감소함을 알 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제19권2호
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• pp.178-183
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• 1998

Carbon-13 CP-MAS NMR techniques were used to investigate dynamics of new combined type liquid crystalline polymers, poly[oxy-1,4-phenyleneoxy-2-{6-(4-(4-butylphenylazo)phenoxy)hexyloxy}terephthaloyl] and poly[oxy-1,4-phenyleneoxy-2-{10-(4-(4-butylphenylazo)phenoxy)decyloxy}terephthaloyl]. Noticeable mobility change of either aromatic groups or methylene groups is not detected between 25 ℃ and 82 ℃ from 13C spinlattice relaxation time in the rotating frame (T1ρ(C)) and contact time array experiments. However, line shape analysis shows the increase of mobility of methylene carbons in poly[oxy-1,4-phenyleneoxy-2-{6-(4-(4-butylphenylazo)phenoxy)hexyloxy}terephthaloyl] at higher temperature. The dynamics of side chanis does not seem to be affected in our experimental temperature range by the length of aliphatic chain which is connecting the side chain group to the main chain.

• 한국동물학회지
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• 제19권2호
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• pp.63-70
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• 1976

免疫抗體分子의 基本 構造成分인 H-chain, L-chain외에 重合抗體分子 속에서만 발견되는 이른바, J-chain의 構造와 機能을 밝히기 위한 前段階로 J-chain의 純粹分離를 試圖하였다. 우선 多發性骨髓腫 患者의 血淸으로부터 重合型 IgA를 純粹分離한후, 이를 환원시켜 L-J-chain 混合物을 얻은 다음 3가지 方法, 1) 제조용 디스크 전기영동법 2) 脫鹽 透析法, 3) 이온-교환 크로마토그라피법으로 J-chain을 순수분리할 수 있었다. 위 3가지 방법으로 분리한 J-chain의 物理化學的 및 生化學的 성상은 동일하였으며, 사용한 세가지 방법 중 脫鹽 透析法이 가장 간편하고 효과적인 方法임을 알았다.

• 한국정보과학회논문지:정보통신
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• 제31권1호
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• pp.112-122
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• 2004

본 논문에서는 이동 컴퓨팅 환경에서 셀 내부 영역에 기반을 둔 이동성 예측 모델과 모바일 호스트들의 이동성을 토대로 하는 이동성 등급을 동적으로 조정할 수 있는 자원 예약 기법을 제안한다. 본 논문에서 제안하는 이동성 예측 모델은 셀 내부의 각각 다른 영역을 기반으로 가약 마코프 체인을 이용하여 모델링 하였으며, 새로운 방법으로 핸드오프 확률을 추정한다. 그리고 모바일 호스트들이 셀 내부에 머물 가능성이 있는 셀 내부 존재 시간을 제공하며, 그 셀 내부 존재 시간은 동적인 자원 예약 기법의 새로운 인자로 활용된다. 동적인 자원 예약 기법은 모바일 호스트들의 내부 존재 시간의 마감에 따라서 변화하는 이동성 등급을 이용하여 이웃 셀의 자원을 동적으로 예약한다. 이 기법들은 신규 호 블록킹율과 핸드 오프 호 종료율을 개선시켰다.