• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2001년도 춘계학술대회 논문집
• /
• pp.243-248
• /
• 2001

A radial artery pulse wave is well known as a good mans to diagnose human body condition in th field of Chinese medical science. Information about constitution as well as organs can be obtained by detecting the artery pulse wave. Recently, the information about the human body constitution may be utilized in accelerating the recovery process of the patient on the basis of comprehensive diagnosis. A radial artery pulse wave is considered as one of promising means in examining the human body constitution. Since the examination has been conducted by the feeling of finger, the diagnosis may occasionally have uncertainty or fatal error. In this paper, a new measuring system is suggested and developed to examine the pattern of a pulse wave correctly. The system is composed of four pressure vessels, pressure sensors and air supplying pumps. One of them is utilized for appropriately pressing the radial artery, three of them for detecting pressure change in several mmHg level. The detected data is shown and discussed.

• Journal of Advanced Marine Engineering and Technology
• /
• 제30권3호
• /
• pp.428-437
• /
• 2006

This paper attempts to derive and analyze the dynamic system of grasping a rigid object by means of two multi-degrees-of-freedom robot flngers with soft and deformable tips. It is shown firstly that a set of differential equation describing dynamics system of the manipulators and object together with geometric constraint of tight area-contacts is formulated by Lagrange's equation. It is shown secondly that the problems of controlling both the forces of pressing object and the rotation angle of the object under the geometric constraints are discussed. In this paper. the control method for dynamic stable grasping and enhancing dexterity in manipulating things is proposed. It is illustrated by computer simulation that the control system gives the performance improvement in the dynamic stable grasping of the dual fingers robot with soft tips.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 1997년도 추계학술대회 논문집
• /
• pp.323-326
• /
• 1997

Conventional robots actuated by motors with the speed reducer such as harmonic drive had weakness in delivering loads, pressing, grinding, and cutting jobs. To overcome this, the developer a new type of robot actuated by the ball screw. The robot is an articulated shape, which is composed of four axes. The base axis is actuated similarly with conventional robot, but the others are actuated by four bars mechanism composed of the ball screw. We setup the dynamics model of the robot. The robot has parameter uncertainties and nonlinearlity due to the ball screw actuator. To coordinate the robot, we applied sliding-mode control.

• 한국산업융합학회 논문집
• /
• 제18권4호
• /
• pp.231-240
• /
• 2015

In this paper, it was presented to design and analyze the kinematics of grasping a rigid object by means of multi-degrees-of-freedom hand fingers. It is shown firstly that a set of kinematic equation describing dynamics system of the arm and object together with geometric constraint of tight area-contacts is formulated by Lagrange's equation. It has been presented secondly that the problems of controlling both the forces of pressing object and the rotation angle of the object under the geometric constraints are discussed. In this research, the control method for static stable grasping and enhancing dexterity in manipulating things is proposed. It is illustrated by computer simulation that the control system gives the performance improvement in the kinematic grasping of the hand fingers of robot.

• Journal of the Optical Society of Korea
• /
• 제11권3호
• /
• pp.85-92
• /
• 2007

In the past, precision optical glass lenses were produced through multiple processes such as grinding and polishing, but mass production of aspheric glass lenses requiring high accuracy and having complex profile was rather difficult. In such a background, the high-precision optical glass molding pressing (GMP) process was developed with an eye to mass production of precision optical glass parts by molding press. In this paper, as a fundamental research to develop the multi-cavity mold for higher productivity of a progressive GMP process used in the fabrication of an aspheric glass lens, an aspheric glass lens forming simulation was carried out.

• 한국분말야금학회:학술대회논문집
• /
• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
• /
• pp.514-515
• /
• 2006

In this study, multi-ply SiC fiber reinforced Ti-6Al-4V composites have been manufactured by plasma spraying and subsequent vacuum hot pressing. Two different sizes of Ti-6Al-4V feedstock powders were used for plasma spraying to form matrix. A considerable amount of oxygen was incorporated into as-sprayed Ti matrix during plasma spraying, and consequently caused matrix embrittlement. The use of coarse-sized feedstock powder reduced oxygen contamination, but tended to increase fiber spacing irregularity and fiber strength degradation. Longitudinal tensile strength and ductility of the composites were mainly affected by the matrix oxygen content.

• 한국정밀공학회지
• /
• 제21권11호
• /
• pp.155-162
• /
• 2004

The volume of the metal is not changed for the plastic deformation. For metal forming simulation, rigid-plastic FEM codes are widely used. Updating geometry using Euler method in the simulation, the volume loss is occurred. In this paper, hybrid method is introduced to perform a more accurate simulation reducing computation time. In the proposed hybrid method, RK2 method is used for geometry updating at first time step and after the boundary condition of the node is changed. At the others, Adams-Bashforth or theta method is applied to update geometry. The results show that the simulations of upsetting and side-pressing can be performed within 0.02％.

• Journal of Veterinary Science
• /
• 제23권4호
• /
• pp.59.1-59.5
• /
• 2022

Korean Institutional Animal Care and Use Committee (IACUC) is currently facing some operational pressing issues. 1) Review of the animal protocol containing controversial technology. 2) Review of the multi-institution animal protocol. 3) Review of veterinary clinical trials for client-owned animals. 4) Delay in the review process in large institutions with a single IACUC. Here, the following three solutions are proposed to address the above issues. 1) Establishment of public IACUC. 2) Establishment of the Veterinary Clinical Study Committee as an advisory body to the IACUC. 3) Operating multiple committees rather than increasing the number of committee members on a single committee.

• 로봇학회논문지
• /
• 제17권2호
• /
• pp.152-158
• /
• 2022

As various mobile robots and manipulator robots have been commercialized, robots that can be used by individuals in their daily life have begun to appear. With the development of robots that support daily life, the interaction between robots and humans is becoming more important. Manipulator robots that support daily life must perform tasks such as pressing buttons or picking up objects safely. In many cases, this requires expensive multi-axis force/torque sensors to measure the interaction. In this study, we introduce a low-cost two-axis pressure sensor that can be applied to manipulators for education or research. The proposed system used three force sensitive resistor (FSR) sensors and the structure was fabricated by 3D printing. An experimental device using a load cell was constructed to measure the biaxial pressure. The manufactured prototype was able to distinguish the +-x-axis and the +-y-axis pressures.

• 한국세라믹학회지
• /
• 제41권6호
• /
• pp.456-463
• /
• 2004

음극지지형 SOFC의 성능을 향상시키기 위해 단전지 제조공정을 개선하고 그 출력특성을 평가하였다. 액상응결 공정(Liquid Condensation Process : LCP)과 일축가압성형공정을 통하여 NiO/YSZ 복합체 음극기판을 제조하고 위에 YSZ 전해질을 스크린 인쇄한 후 140$0^{\circ}C$에서 3시간동안 동시소결하여 음극/전해질 기판을 제조하였다. 또한 LSM/YSZ 양극층은 임피던스 분석을 통해 분극저항이 최소가 되는 조성 및 열처리 조건을 선택하여 스크린 인쇄법을 이용해 구성하였고 이러한 적층공정을 거쳐 최종적으로 5${\times}$5와 l0${\times}$10 $\textrm{cm}^2$ 크기의 단전지를 제조하였다. 제조된 단전지의 출력특성을 측정한 결과 5${\times}$5와 10${\times}$10 단전지는 80$0^{\circ}C$에서 약 0.45W/$\textrm{cm}^2$ 와 0.22 W/$\textrm{cm}^2$의 최대출력밀도를 각각 나타내어 선행연구에서 기존공정으로 제조된 단전지에 비해 2배 이상 향상된 좋은 성능을 나타내었다.