• 제목/요약/키워드: base point

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역동역학에 의한 병진운동 탄성 Arm 선단의 위치제어 (The End-Point Position Control of a Translational Flexible Arm by Inverse Dynamics)

  • 이성철;방두열
    • 한국정밀공학회지
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    • 제9권4호
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    • pp.136-146
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    • 1992
  • This paper provides the end-point positioning of a single-link flexible robot arm by inverse dynamics. The system is composed of a flexible arm, the mobile ballscrew stage as an arm base, a DC servomotor as an actuator, and a computer. Actuator voltages required for the model of a flexible arm to follow a given tip trajectory are formulated on the basis of the Bermoullie-Euler beam theory and solved by applying the Laplace transform method, and computed by the numerical inversion method proposed by Weeks. The mobile stage as the arm base is shifted so that the end-point follows the desired trajectories. Then the trajectory of end-point is measured by the laser displacement sensor. Here, two kinds of functions are chosen for the given tip trajectories. One is what is called the bang-bang acceleration profile and the other is the Gaussian velocity profile.

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액상확산접합용 인서트금속의 화학조성 최적화에 관한 연구 (A Study on the Optimum Chemical Composition of Insert Metal for Liquid Phase Diffuse Bonding)

  • 김대업;정승부;강정윤
    • Journal of Welding and Joining
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    • 제18권5호
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    • pp.90-97
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    • 2000
  • Effect of alloy elements on joinability of insert metal for liquid phase diffusion bonding of heat resistant alloys was investigated in this study. Also, optimum chemical composition of insert metal was explained using interpolation method. The insert metals utilized was commercial Ni-base amorphous foils and newly developed Ni-base filler metals with B, Si and Cr in this study. Melting point and critical interlayer width(CIW) decreased with increasing additional amount of B, Si and Cr, melting point lowering element of the insert metal. Optimized chemical composition of insert metals could be estimated by interpolation method. The optimum amount of B, Si, Cr addition into the insert metal were found to be about 3%, 4% and 3%, respectively. The measured characteristic values, melting point, microhardness in the bonded interlayer and CIW of the insert metals were the almost identical to ones of the calculated results by interpolation method.

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Targeted Base Editing via RNA-Guided Cytidine Deaminases in Xenopus laevis Embryos

  • Park, Dong-Seok;Yoon, Mijung;Kweon, Jiyeon;Jang, An-Hee;Kim, Yongsub;Choi, Sun-Cheol
    • Molecules and Cells
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    • 제40권11호
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    • pp.823-827
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    • 2017
  • Genome editing using programmable nucleases such as CRISPR/Cas9 or Cpf1 has emerged as powerful tools for gene knock-out or knock-in in various organisms. While most genetic diseases are caused by point mutations, these genome-editing approaches are inefficient in inducing single-nucleotide substitutions. Recently, Cas9-linked cytidine deaminases, named base editors (BEs), have been shown to convert cytidine to uridine efficiently, leading to targeted single-base pair substitutions in human cells and organisms. Here, we first report on the generation of Xenopus laevis mutants with targeted single-base pair substitutions using this RNA-guided programmable deaminase. Injection of base editor 3 (BE3) ribonucleoprotein targeting the tyrosinase (tyr) gene in early embryos can induce site-specific base conversions with the rates of up to 20.5%, resulting in oculocutaneous albinism phenotypes without off-target mutations. We further test this base-editing system by targeting the tp53 gene with the result that the expected single-base pair substitutions are observed at the target site. Collectively, these data establish that the programmable deaminases are efficient tools for creating targeted point mutations for human disease modeling in Xenopus.

오유혈(五兪穴)을 이용한 사시자법(四時刺法) -영추(靈樞)와 난경(難經)을 중심으로- (Study on Acupuncture Follow the Four Season)

  • 홍원식;엄동명
    • Journal of Acupuncture Research
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    • 제17권4호
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    • pp.18-27
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    • 2000
  • There is a acupuncture method which make a difference according to the four seasons, according to body region or depth in skin. We call it Acupuncture follow the four seasons(四時刺法). In several chapters of Huangdineijing(黃帝內經) introduced Acupuncture follow the four seasons. Acupuncture follow the four seasons has two kinds of acupuncture method that is to acupuncture at body region and to acupuncture at five Su points(五兪穴). To use five Su points(五兪穴) according to Yongchu(靈樞) disagree with Nanjing(難經). In Yongchu(靈樞), the five phases property disagree with five Su points(五兪穴), but in Nanjing(難經) the five phases property agree with five Su points(五兪穴). Even if we can acupuncture the same point, there will be the different effect according as what is the purpose of doing acupuncture, and when we do acupuncture. That is to say, we can use apucupuncture for the purpose of prevention in Yongchu(靈樞), and for the purpose of healing the disease in Nanjing(難經). Therefore, because we select the point on the base of meridian Kis origin which spring out, we have to acupuncture Chong point(井穴) in winter according to Yongchu(靈樞). Because we select the point on the base of meridian Kis origin which flowing, we have to acupuncture Chong point(井穴) in spring according to Nanjing(難經). And in the base of five phases' property, the purpose of selecting five Su points(五兪穴) is the prevention according to Yongchu(靈樞), and the healing according to Nanjing(難經). So even though we acupuncture the exactly same Chong point(井穴), we can expect the effect that acupuncture method supply Ki for liver in winter. and the effect that it extract pathogenic Ki(邪氣) from the liver in spring.

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Cu-Sn 삽입금속을 이용한 DP강의 아크 브레이징 접합부의 미세조직과 인장특성 (Microstructure and Tensile Strength Property of Arc Brazed DP steel using Cu-Sn Insert Metal)

  • 조욱제;조영호;윤중길;강정윤
    • Journal of Welding and Joining
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    • 제31권1호
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    • pp.58-64
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    • 2013
  • The following results were obtained, microstructures and tensile properties in arc brazed joints of DP(dual phase) steel using Cu-5.3wt%Sn insert metal was investigated as function of brazing current. 1) The Fusion Zone was composed of ${\alpha}Fe+{\gamma}Cu$ and Cu23Sn2. The reason for the formation of these solid solutions. Despite, Fe & Cu were impossible to solid solution at room temperature. It's melting & reaction to something of insert metal & Base Metal (DP Steel) by Arc. Brazing Process has faster cooling rate then Cast Process, Supersaturated solid solution at room temperature. 2) The increase Hardness of Fusion Zone was directly proportional to the rise of welding current. Because, ${\alpha}Fe+{\gamma}Cu$ phase (higher hardness than the Cu23Sn2.(104.1Hv < 271.9Hv)) Volume fraction was Growth, due to increasing the amount of base metal melting by High current. 3) The results of tensile shear test by Brazing, All specimens happen to fracture in Fusion Zone. On the other hand, when Brazing Current increasing tend to rise tensile load. but it was very small, about 26-30% of the base metal. 4) The result of fracture analysis, The crack initiate at Triple Point for meet to Upper B.M/Under B.M/Fusion Zone. This Crack propagated to Fusion zone. So ruptured by tensile strength. The Reason to in the fusion zone fracture, Fusion zone by Brazing of hardness (strength) was very lower then the base metal (DP steel). In addition the Fusion Zone's thickness in triple point was thin than the base metal's thickness in triple point.

통신기지국 접지계의 써어지해석 (A Study on the Surge Analysis for Grounding System of the Communication Base Station)

  • 김재이;윤태양
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 하계학술대회 논문집 C
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    • pp.2025-2027
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    • 2004
  • The grounding system design of the communication base station can be on the unfavorable conditions to induce the safe designing because of the limited area of the communication base station and the week point of surge caused by the given geographical condition such as the top point of mountain. In this paper, it is examined throughly about the way of safe designing that can reduce GPR(Ground Potential Rise) within the normal frequency band. And it is also considered the effective counter plan to cope with a transient phenomena that happen when surge of scores MHz-band inserted.

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음함수 곡면기법을 이용한 폴리곤 모델의 홀메움에 관한 연구 (A Study on Filling Holes of the Polygon Model using Implicit Surface Scheme)

  • 유동진
    • 한국정밀공학회지
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    • 제22권3호
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    • pp.107-114
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    • 2005
  • A new approach which combines implicit surface scheme and point projection method is presented in order to fill the arbitrarily shaped holes in the polygon model. In the method a trimmed surface which has an outer boundary curve is generated by using the implicit surface scheme and normal projection of point onto the base surface. The base surface is constructed by creating smooth implicit surface from the incomplete polygon model through which the surface should pass. In this paper an implicit surface is defined by a radial basis function, a continuous scalar-valued function over the domain $R^3$. The base surface is the set of all points at which this scalar function takes on the value zero and is created by placing zero-valued constraints at the vertices of the polygon model. In order to show the validity of the present study, various hole fillings are carried out for the complex polygon model of arbitrary topology.

전동휠체어 자동 주행을 위한 복도영상 해석 (The Corridor Scene Analysis for a Motorized Wheelchair's Automatic Locomotion)

  • 문철홍;한영환;홍승홍
    • 대한의용생체공학회:의공학회지
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    • 제15권1호
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    • pp.27-34
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    • 1994
  • In this paper. a way to analysis a corridor scene for a vehicle's automatic locomotion is presented In general, it's necessary for a vision system of vehicles to identify its positions in given environments. The suggested algorithm is to decide base lines of a corridor image using the vanishing point finding. Feature points are extracted on the base line using a base line extraction tree. This algorithm is suitable for a motorized wheelchair's self locomotion in a building.

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Comparison of monotonic and cyclic pushover analyses for the near-collapse point on a mid-rise reinforced concrete framed building

  • GUNES, Necmettin
    • Earthquakes and Structures
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    • 제19권3호
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    • pp.189-196
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    • 2020
  • The near-collapse performance limit is defined as the deformation at the 20% drop of maximum base shear in the decreasing region of the pushover curve for ductile framed buildings. Although monotonic pushover analysis is preferred due to the simple application procedure, this analysis gives rise to overestimated results by neglecting the cumulative damage effects. In the present study, the acceptabilities of monotonic and cyclic pushover analysis results for the near-collapse performance limit state are determined by comparing with Incremental Dynamic Analysis (IDA) results for a 5-story Reinforced Concrete framed building. IDA is performed to obtain the collapse point, and the near-collapse drift ratios for monotonic and cyclic pushover analysis methods are obtained separately. These two alternative drift ratios are compared with the collapse drift ratio. The correlations of the maximum tensile and compression strain at the base columns and beam plastic rotations with interstory drift ratios are acquired using the nonlinear time history analysis results by the simple linear regression analyses. It is seen that these parameters are highly correlated with the interstory drift ratios, and the results reveal that the near-collapse point acquired by monotonic pushover analysis causes unacceptably high tensile and compression strains at the base columns, as well as large plastic rotations at the beams. However, it is shown that the results of cyclic pushover analysis are acceptable for the near-collapse performance limit state.

윤활기유의 조성이 전기절연유의 성능 및 특성에 미치는 영향 (The Effect of Base Oil Composition on Electronic Insulating Oil's Performances)

  • 문우식;전정식
    • 한국윤활학회:학술대회논문집
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    • 한국윤활학회 1998년도 제28회 추계학술대회
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    • pp.181-189
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    • 1998
  • In order to investigate the effect of base oil composition on the electronic insulating oil's performances, an experimental study has been conducted using different oils. Owing to their properties, like lower pour point and gas absorbing, naphthenic base oils are used more often than paraffmic base oils for the electronic insulating oil application. Naphthenic and paraffinic base oils are significantly different in their aromatic hydrocarbon content. In this paper, PXE(para xylyl ethane), LAB(linear alkylbenzene), C13 aromatic hydrocarbon mixture and C17 aromatic hydrocarbon mixture are investigated regarding their influence on insulating oil's performances. According to present study, breakdown voltage decreased with increasing aromatic lydrocarbon content in a deep dewaxed paraffmic base oil. However, any changing in the dissipation factor was not recognizable at small treated level. Furthermore, the volume resistance was not influenced by aromatic hydrocarbon content. The gassing tendency was found as a highly sensible property, changing with treating aromatic hydrocarbons. The higher benzene ring content in the hydrocarbon, the better gassing tendency.

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