• 한국정밀공학회지
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• 제24권6호
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• pp.78-85
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• 2007

In this study, we performed finite element analysis for the design of a medical centrifuge and two-types of centrifuge were compared with each other. The types of centrifuge are 2-arm straight type and 3-arm type. Structural analysis was done with respect to the change of the rotational speed of the rotor of a centrifuge. When the rotor of centrifuge was rotated, the von Mises stress of 2-arm straight type-rotor was compared with the von Mises stress of 3-arm type. The margin of safety was estimated from the result. We found the critical speed of centrifuge from the campbell diagram by modal analysis.

• 대한인간공학회지
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• 제16권1호
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• pp.29-45
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• 1997

This study aims at designing sleeves which are suitable for arm shapes and arm movements. With the samples of of ordinary 24 women aged from 20 to 22, the arm shapes and movements were measured 3-dimensionally using a motion analyzer and a sonic digitizer, and then clasified into three characteristic types (A, B, and C). Our analysis leads to the following conclusion. The factors classifying arm shapes are the length from acromion to posterior armpit point, arm hole length, the cap height, difference in height between anterior and posterior armpit points, armhole circumference, upper arm circumferemce, armhole depth, and underarm circumference. The characteristics of arm type A is that the armhole depth and the length from acromion to posterior armpit point are the largest, while the circumference inbe- tween upper arm and elbow is the smallest among the three arm types. Thus, the large circumference difference between upper and lower arms is the most notable in arm type A. The factors classifying arm shapes for arm type B are the smallest except for the circumference inbetween upper arm and elbow which is larger than that for arm type A. The circumference difference betweemn upper and lower arms is small for arm type B. Arm type C has the smallest armhole depth, while other factors are similar to those for arm type B. In type C, the size of upper arm is comparatively small on the frontal plane, while it is the largest on the sagital plane.

• 천문학회지
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• 제46권3호
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• pp.141-149
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• 2013

We analyze the spiral structure of 1725 nearby spiral galaxies with redshift less than 0.02. We use the color images provided by the Sloan Digital Sky Survey. We determine the arm classes (grand design, multiple-arm, flocculent) and the broad Hubble types (early, intermediate, late) as well as the bar types (SA, SAB, SB) by visual inspection. We find that flocculent galaxies are mostly of late Hubble type while multiple-arm galaxies are likely to be of early Hubble type. The fractional distribution of grand design galaxies is nearly constant along the Hubble type. The dependence of arm class on bar type is not as strong as that of the Hubble type. However, there is about a three times larger fraction of grand design spirals in SB galaxies than in SA galaxies, with nearly constant fractions of multiple-arm galaxies. However, if we consider the Hubble type and bar type together, grand design spirals are more frequent in early types than in late types for SA and SAB galaxies, while they are almost constant along the Hubble type for SB galaxies. There are clear correlations between spiral structures and the local background density: strongly barred, early-type, grand design spirals favor high-density regions, while non-barred, late-type, flocculent galaxies are likely to be found in low-density regions.

• 한국기계가공학회지
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• 제7권2호
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• pp.3-7
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• 2008

A polishing machine adopting a new unique structural mechanism has been developed, named as a swing-arm type polishing machine. The mechanism is such that the tool path tracks on a spherical surface, of which the diameter is adjusted by setting up the machine mechanism properly. It has a strong benefit especially for polishing axis-symmetric concave mirror surfaces. The swing-arm type polishing machine with 5-axes has been designed in order to polish a concave mirror surface lip to diameter of 2 meters. The drawings are made using 3D CAD and strain-stress analysis has been done by finite element method. AC servo-motor has been used to move the swing arm and a operating software has been developed using a LapVIEW tool. Result of the test run was satisfactory which convinces the usefulness of the swing-arm type polishing machine.

• 한국의류학회지
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• 제27권2호
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• pp.219-228
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• 2003

The purpose of this study were to examine the characteristics of arm types proposed in the previous study and to present sleeve patterns according size and shape of 4 arm types. 31 direct and indirect items were measured. The subjects for this study were 132 females of twenties. The results were as follows. 1. All of the direct measurements showed significant difference by the arm types. especially at the front armhole part. Such a.: the items of arm gradients, armhole sizes belong to the indirect measurements made clear difference also. 2. By the discriminant analysis, 9 items including underarm length, front armhole girth, upper arm girth, degree of elbow point-wrist point discriminated arm type by the hit ratio of 90.4% Item related to shape of arm rather than size made a sharp distinction. 3. Through the examination of existing patterns and wearing tests on the subjects among 4 groups, sleeve patterns classified by the arm type were suggested.

• Journal of Biosystems Engineering
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• 제36권5호
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• pp.314-318
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• 2011

Arm-type implements of tractor are mainly utilized for the slope land operation. The proposed hydraulic system was implemented to arm-type implements of tractor. An experiment was conducted to evaluate response characteristics of the designed arm-type implement control system attached by three-point hitch of tractor at various conditions, such as engine speed, pumping rate and cylinder input flow. Effects of the valve response time didn't affect engine speed. The flow rate of pump and cylinder changed to the pressure loss. Also, the pressure loss was within 2 MPa and the response characteristic was sufficient enough to use as the arm-type implement system.

• 한국자동차공학회논문집
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• 제6권3호
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• pp.18-25
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• 1998

This paper performed stress analysis and bench test for the LOWER ARM of H' type which was improved on LOWER ARM with the section of H type. And we investigated the safety of the section of H' type. The results of this study are as follows ; The section of H' type satisfied the required safety factor and has the highest stress value on the B part of the LOWER ARM. And the magnitude is similar to the fatigue strength of the GCD45(300㎫). Hence, the H' type has an advantage to reduce the cost of production.

• 한국정보통신학회논문지
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• 제13권7호
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• pp.1335-1343
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• 2009

본 논문에서 진행한 연구는 고속의 ARM 아키텍처 기반의 ARM11 코어를 적용한 최신 MPU인 S3C6400을 이용한 플랫폼을 구현하고 구현된 플랫폼에 OS로서 리눅스를 포팅하여 Handheld 타입의 가스 센서용 플랫폼 구현에 관한 연구이다. 무선으로 데이터를 전송받기 위하여 블루투스를 이용한 네트워크 환경을 구축하였다. QT/embedded를 사용하여 리눅스 상에서 유연한 어플리케이션 개발 환경을 구축하여 관련된 프로그램을 작성하였다.

• 한국전산구조공학회논문집
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• 제14권3호
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• pp.267-276
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• 2001

이 논문은 회전식 수문(radial gate)의 구조해석에 근거하여 지지점 위치에 따른 모멘트 분배를 최적화하는 것에 관심을 두고 있다. 회전식 수문(radial gate)의 경제적인 관점에서의 중요성에도 불구하고 이의 지지점 위치에 따른 최적설계에 관한 자료를 찾기 어려운 실정이다. 그래서 본 연구에서는 주판(skin plate)의 곡률 반경, 수심, 동압 등의 주어진 자료를 이요약하여 지지점(gate arm)의 수가 2개인 경우와 3개인 경우에 대하여 곡선형태의 주판(skin plate)에서 지지점 (arm)의 최적 위치를 얻어서 설계자료에 의한 것들과 비교한다. 그 결과 최적 설계에 의한 회전식 수문 (radial gate)의 치수가 설계자료에 의한 것에 비해 현저히 감소되는 것을 알 수 있다.

• 한국운동역학회지
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• 제16권4호
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• pp.153-164
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• 2006

This thesis is focused on kinematical and kinematical analysis of each types(Type #1 : use both swing of arm and reaction of knee, Type #2 : Use only swing of arm, not reaction of knee, type #3 : Neither use of swing of arm nor reaction of knee) of vertical jumps according to gender of High School Students. The subjects of this study is High School Student's male and female, 5 each, for analyzation of actions 3D image analyzing and GRF machines were used. To identify the differences of analyzed variables, an independent T-test on gender, an One-way ANOVA on types were used. Summery of the results are stated below. first of all, female students showed differences on Hip Joint angle and Joint Velocity from male students on Kimentic Variable. So training on hip joint force of flection and extension of female students is needed. Both male and female students showed relatively bigger result of arm's Angular Momentum than thigh's Angular Momentum on Type #1. This is regarded of faster Joint Velocity of Arm. Bigger result of female students of arm's contribution on Type #1 than male students can be said as Female student's weaker hip joint's angular muscle force than male student's, so the dependency of arm is heavier than male students. In Kinetic variable, GRF showed bigger result on male students than female students. So female students need to enhance joint's torque to increase GRF than male students. On vertical Impulse, high numeric data of last two reaction of tiptoe of vertical GRF and antero-posterior GRF helped increasing impulse by extending action time of force.