• Title/Summary/Keyword: length measurement

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Development of a precision length measuring system by using laser (레이저를 이용한 정밀 길이 측정시스템 개발)

  • 김진상;정성종
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.1415-1418
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    • 1997
  • An accurate length measuring system has been develope by a modified Michelson interferometer. A frequency stabilized laser source and a 20 fold frequency interpolation and digitizing circuit were applied to the system. Resolutioin of .lambda./40, 16 nm, was achieved from the discrete length measuring system. In order to obtain a resoltuion of 1.mu.m a decimalizing module was designed for the 0.016.mu.m resolution system. The refractive index of the ambient air was calibrated on the decimalizing module through the Edlen's formula. Performance of the system was evaluated on the machining center in short and long length measruements.

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On the Total Length and Body Weight of the File File Fish , Navodos Modestus Caught in the Sonthern Sea Area of Komundo Is . During Summer (여름철 거문도 남부해역에서 어획된 말쥐치의 체장과 체중 조성)

  • 염말구
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.22 no.4
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    • pp.71-74
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    • 1986
  • The author tried to clarify the distribution of the total length and body weight of the file h, Navodos modcstus, caught by trawl net during July, 1984 in the southern sea korea. Among the catches of five times fishing operation, 1540 individuals were randomly sampled for the measurement. The results are summarized as follows; " The distribution of total length showed bimodal type, wbich was able to analyzed into two normal distributions N(17.46, 1. 02^2) and N(22.09, 1. 77^2). And smaller group was much than older one. The age of the sample estimated from the total length distribution of. smaller group was 1. 5 to 2, and the larger group 2. 5 to 4. The relationship between the total length and the body weight can be presented as following equation: $$W=0.01726 L^{2.8507}$$ ' or $$W= 0.01109 L^{3.0}$$ or $$W= 0.01109 L^{3.0}$$.

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A study on the measurement of plastic zone and crack growth length at the crack tip under cyclic loading using ESPI system

  • Kim, Kyung-Su;Kim, Ki-Sung;Shim, Chun-Sik
    • Structural Engineering and Mechanics
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    • v.15 no.3
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    • pp.367-378
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    • 2003
  • The magnitude of the plastic zone around the crack tip of DENT (Double Edge Notched Tension) specimen and the crack growth length under cyclic loading were measured by ESPI (Electronic Speckle Pattern Interferometry) system. The measured magnitude of plastic zone was compared with the proposed by Irwin and calculated by a nonlinear static method of MSC/NASTRAN. The measured crack growth length by ESPI system was also compared with the obtained data by the image analysis system. From the study, it is confirmed that the plastic zone and crack growth length can be measured accurately with the high-tech equipment (ESPI System).

The Relationships between Hand Function and Characteristics of Hand (손기능과 손의 특성과의 관계)

  • Lee, Sun-Myung
    • Journal of Korean Clinical Health Science
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    • v.3 no.3
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    • pp.409-418
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    • 2015
  • Purpose. This study was to investigate the relationship between hand function and characteristics of hand. Methods. Participants were 56 occupational therapy students who studied in M colleges in Gyengsangnam-do, april 20, 2015 from 1 May, and hand circumference and length (vertical, w), the width was measured. A hand grip on the measurement subject was measured by the Grip dynamometer and Pinch gauge. Results. The results was hand length, width, circumference long, broad, thick, and hand strength was a greater correlation emerged. Grip strength was showed a significant correlation to the size and grip strength was also correlated. Conclusion. This study was correlation of length of the hand, a length wide and strength of the finger circumference.

Relation between Radar Backscattering Coefficients and Surface Profile Length for Bare Soil Surfaces Using Theoretical Predictions and Measurement Data (토양 표면에서의 레이더 산란 계수와 표면 거칠기 측정 길이의 관계에 대한 이론 모델과 측정 데이터의 비교)

  • Oh, Yi-Sok;Hong, Jin-Young
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.17 no.12 s.115
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    • pp.1181-1188
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    • 2006
  • The radar backscattering coefficients of soil surfaces with various roughness conditions are computed at first in this paper. The roughness parameters for various surface-profile lengths are also obtained. Then, the relationship between the radar backscattering coefficients and the profile length is studied. It was shown that the effect of the profile length is negligible on the backscattering coefficient, even though the roughness parameters vary a lot with the length of the surface profile.

Effect of Polymerization Procedure on Thermal and Mechanical Properties of Polyether Based Thermoplastic Polyurethanes

  • Kim, Seong-Geun;Lee, Dai-Soo
    • Macromolecular Research
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    • v.10 no.6
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    • pp.365-368
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    • 2002
  • Thermoplastic polyurethanes (TPUs) with different hard segment length has been prepared from a fixed molar ratio of poly(tetramethylene ether glycol), 4,4'-diphenylmethane diisocyanate, and 1,4-butanediol by different polymerization procedures. Results reveal that the on-set temperature of endotherms ( $T_{cc}$ ) due to the crystallization of hard segments by cooling the TPUs from melt and the peak temperature of endotherms due to the melting of hard segments ( $T_{mh}$ ) by heating the TPUs increased and levelled off with increasing the hard segment length of TPUs. It has also been observed that soft segment glass transition temperature ( $T_{gs}$ ) of TPU decreased slightly with increasing the hard segment length, which explains less mixing of soft segments and hard segments. In tensile measurement of TPUs, strain hardening is observed with increasing the hard segment length, which is attributed to the strain induced crystallization of soft segments.

A Study on the Measurement of Break-up Length for the Diesel Sprays (디젤분무의 분열길이 측정에 관한 연구)

  • Jang, S.H.;Ra, J.H.
    • Journal of Power System Engineering
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    • v.3 no.3
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    • pp.22-28
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    • 1999
  • The injected liquid does not break-up instantly after injection for diesel engine. There is some unbroken portion, which is the liquid core(The length of liquid core is called the break-up length) in the spray. If the liquid core is longer than the depth of the bowl in the small DI diesel engine, the liquid core impinges on the surface of the piston. Once the liquid core impinges on the surface, it cannot ignite or burn rapidly and thus prolongs burning time with a degradation in thermal efficiency. The break-up length of a diesel spray in a compressure vessel was measured by an electric resistance method, A voltage was applied between the nozzle and screen, bar, needle electrode inserted at various axial and radial positions into atomizing sprays. As a result, a current flows not only in the region of liquid core but also through the droplets of the spray. It is found that the break-up length measured with screen electrode is overestimated. The break-up length of the spray is found to be proportional to the square root of the density ratio of fuel and surrounding gas. The break-up length of the spray decreases as the injection pressure and the back pressure increase.

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Effects of root trunk length after GTR on clinical outcomes (하악 제1대구치 치근본체의 길이가 조직유도재생술의 임상결과에 미치는 영향)

  • Pi, Sung-Hee;Shin, Hyung-Shik
    • Journal of Periodontal and Implant Science
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    • v.36 no.2
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    • pp.427-434
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    • 2006
  • The form of furcation influence both the pathogenesis of periodontal destruction and therapeutic results. The present study was performed to evaluate the effect of root trunk length on clinical outcomes of guided tissue regeneration. Total 30 mandibular first molars were evaluated in this study. Probing pocket depth, clinical attachment level, vertical defect depth and horizontal defect depth were measured at baseline and 6 month after GTR. Correlation coefficients between root trunk length and other clinical measurement were analyzed. The results of this study were as follows 1. The mean root trunk length in lower 1st molar was 2.15 mm. 2. Probing pocket depth, clinical attachment level, vertical defect depth and horizontal defect depth were significantly reduced at 6 month postoperatively compared to values of baseline 3. Correlation coefficient between root trunk length and vertical defect depth at baseline was 0.406 showing the positive correlation 4. Correlation coefficient between root trunk length and horizontal defect depth at baseline was -0.463 showing the negative correlation. 5. Correlation coefficient between root trunk length and decrease of horizontal defect depth after GTR was 0.654 showing the positive correlation. In conclusion, the root trunk length maybe effector for clinical outcome after guided tissue regeneration.

A Study on Changes of Body Measurements in Teenage Boys: Focused on ages 13 to 18 (13-18세 남학생의 인체치수 변화 경향에 관한 연구)

  • Hyun, Eun-Kyong;Nam, Yun-Ja
    • Journal of the Korean Society of Costume
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    • v.59 no.6
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    • pp.58-71
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    • 2009
  • The purpose of this study is to examine the increments of body measurements of the teenage boys between the ages of 13 and 18 and provide a fundamental data for apparel manufacturers in order for them to make clothing that reflect the appropriate body characteristics of the teenage boys. The total of 1587 male subjects between the ages of 13 and 18, from the 5th Anthropometric survey of Korea (Size Korea) data, were used for this study. The changes in the body dimensions were analyzed with anthropometric measurements and anthropometric index mesurements. First, anthropometric measurement results show that most of the height related measurements increased in accordance with age, and that the boys between the ages of 13 and 15 experience dramatic growth. Standard deviation is the largest between the age of thirteen and fourteen which indicates that in these ages there is a wide difference in a growth rate Second, anthropometric index measurement results show that in accordance with age, bust, waist and hip depth/width rate decreased; however, waist and hip depth/width rate increased at the age of 18. In accordance with age, upper body length rate increased, whereas lower body length rate decreased. Bust circumference, armhole length, and upperarm circumference rate increased gradually, whereas waist circumference decreased.

A Study on Measurement and Control of position and pose of Mobile Robot using Ka13nan Filter and using lane detecting filter in monocular Vision (단일 비전에서 칼만 필티와 차선 검출 필터를 이용한 모빌 로봇 주행 위치.자세 계측 제어에 관한 연구)

  • 이용구;송현승;노도환
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.81-81
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    • 2000
  • We use camera to apply human vision system in measurement. To do that, we need to know about camera parameters. The camera parameters are consisted of internal parameters and external parameters. we can fix scale factor&focal length in internal parameters, we can acquire external parameters. And we want to use these parameters in automatically driven vehicle by using camera. When we observe an camera parameters in respect with that the external parameters are important parameters. We can acquire external parameter as fixing focal length&scale factor. To get lane coordinate in image, we propose a lane detection filter. After searching lanes, we can seek vanishing point. And then y-axis seek y-sxis rotation component(${\beta}$). By using these parameter, we can find x-axis translation component(Xo). Before we make stepping motor rotate to be y-axis rotation component(${\beta}$), '0', we estimate image coordinates of lane at (t+1). Using this point, we apply this system to Kalman filter. And then we calculate to new parameters whick make minimum error.

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