• Title/Summary/Keyword: open-chain

Search Result 372, Processing Time 0.03 seconds

A Computer Method for the Dynamic Analysis of a System of Rigid Bodies in Plane Motion

  • Attia, Hazem-Ali
    • Journal of Mechanical Science and Technology
    • /
    • v.18 no.2
    • /
    • pp.193-202
    • /
    • 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.

Length- and parity-dependent electronic states in one-dimensional carbon atomic chains on C(111)

  • Kim, Hyun-Jung;Oh, Sang-Chul;Kim, Ki-Seok;Zhang, Zhenyu;Cho, Jun-Hyung
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2010.08a
    • /
    • pp.56-56
    • /
    • 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.

  • PDF

POSITIVE EXPANSIVITY, CHAIN TRANSITIVITY, RIGIDITY, AND SPECIFICATION ON GENERAL TOPOLOGICAL SPACES

  • Devi, Thiyam Thadoi;Mangang, Khundrakpam Binod
    • Bulletin of the Korean Mathematical Society
    • /
    • v.59 no.2
    • /
    • pp.319-343
    • /
    • 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.

The Effect of Chain Exercise Types on the Exercise Performance Improvement in Lower Limb Exercise for the Life-Carement (라이프케어먼트를 위한 신체운동수행능력 향상에 사슬운동형태가 미치는 효과 연구)

  • Yang, Seung-Hoon
    • Journal of Korea Entertainment Industry Association
    • /
    • v.14 no.8
    • /
    • pp.391-396
    • /
    • 2020
  • This study was to examined the effect of chain types exercise of lower limbs on the motor performance differences for the life-carement. For this, twenty normal adult women participated and they were examined the differences of exercise effects about abdominal muscle activity and balance ability by applying two types of chain exercise. In order to identify the differences we let them conduct exercise for 4 weeks with each type of exercise. And we used paired t-test and Independent sample t-test for comparing the differences in the group and inter groups. There was a significant difference in the value of 0.05 to verify statistical significance. As a result of this research, it was found that closed chain exercise is more effective than open chain exercise in muscle activity and balance function. Therefore, in the clinical therapeutic environment, if you apply chain exercise for patient to improve lower limb motor performance, we would recommend the close kinematic chain exercise.

Nucleotide sequence analysis of a second set of the polyketide synthase .betha.-ketoacyl synthase and chain length factor genes from the salinomycin-producing streptomyces albus

  • Hyun, Chang-Gu;Park, Kwan-Hyung;C.Richard Hutchinson;Suh, Joo-Won
    • Journal of Microbiology
    • /
    • v.35 no.1
    • /
    • pp.40-46
    • /
    • 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.

  • PDF

Study IoT Asset Management System Based on Block-Chain Framework (블록체인 프레임워크 기반 IoT 자산관리시스템)

  • Kang, Sung Won;Kim, Young Chul
    • Smart Media Journal
    • /
    • v.8 no.2
    • /
    • pp.94-98
    • /
    • 2019
  • In this paper, we developed the tools enabling to manage the IoT systems owned by managers. Since equipment agents consists based on open-source block-chain framework, we can secure the invariance on data and furthermore can locate the resources by searching the AP connected to the equipments. Also the manager can trace the connecting details on equipments from their block-chain accounts. In addition, we work on the possibility of protecting ARP poisoning attacks by removing the credibility on additional ARP requests being generated during the process of network creation.

Synthesis of Iron Alkynylcarbene Complexes and Their Reactivies Toward Open-Chain 1,3-Dienes (철 알킨일카르벤 착물 유도체의 합성과 열린 사슬 1,3-디엔에 대한 반응성 연구)

  • Park Jaiwook;Kang Sunhwa;Whang Dongmok;Kim Kimoon
    • Journal of the Korean Chemical Society
    • /
    • v.36 no.5
    • /
    • pp.770-779
    • /
    • 1992
  • Five (alkynylethoxymethylene)$Fe(CO)_4 complexes (1) are prepared through the reaction of Fe(CO)_5$ with alkynyllithium (R = n-Pr, cyclohexyl, t-Bu, trimethylsilyl, Ph) and subsequent O-ethylation of the resulting acyl anion complexes with ethyl fluorosulfonate. In the reactions of trimethylsilyl-substituted alkynylcarbene complex (1d) with 8 open-chain 1,3-dienes, ({\eta}^3-vinylcarbene)Fe(CO)3 complexes (2) are obtained as major products.

  • PDF

The Effect of Closed Kinetic and Open Kinetic Exercise on Thickness of Low Back Stabilization Exercise Using an Ultrasonography Imaging (닫힌사슬운동과 열린사슬운동이 요부안정화근의 두께에 미치는 영향)

  • Bae, Wonsik;Kim, Chihyok
    • Journal of The Korean Society of Integrative Medicine
    • /
    • v.1 no.2
    • /
    • pp.67-80
    • /
    • 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.

Effect of Housing on Physiological Responses and Energy Expenditure of Sheep in a Semi-arid Region of India

  • Bhatta, Raghavendra;Swain, N.;Verma, D.L.;Singh, N.P.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.18 no.8
    • /
    • pp.1188-1193
    • /
    • 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.