• 한국컴퓨터정보학회논문지
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• 제22권10호
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• pp.1-7
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• 2017

In this paper, the separation force measuring system is developed. The separation force aries due to adhesive strength between semiconductor epoxy molding compound(EMC) and the metal plate in semiconductor formed plate. In general, when removing the metal plate in semiconductor formed plate from semiconductor epoxy molding compound, excessive strength can result in a increase in semiconductor defect rates, or conversely, if too little force is exerted on the metal plate in semiconductor formed plate, the semiconductor production rates can decrease. In this study, the design criteria for the selection of the AC servo motor, the role of the ball screw, the relationship between the load cell and the ball screw, and the rate of deceleration are given. In addition, minimizing the reject rate of semiconductors and maximizing the semiconductor production rate are achieved through the standardization of the collected separation force data measured by the proposed system.

• Restorative Dentistry and Endodontics
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• 제42권4호
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• pp.273-281
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• 2017

Objectives: The aims of this study were to quantify tug-back by measuring the pulling force and investigate the correlation of clinical tug-back pulling force with in vitro gutta-percha (GP) cone adaptation score using micro-computed tomography (${\mu}CT$). Materials and Methods: Twenty-eight roots from human single-rooted teeth were divided into 2 groups. In the ProTaper Next (PTN) group, root canals were prepared with PTN, and in the ProFile (PF) group, root canals were prepared using PF (n = 14). The degree of tug-back was scored after selecting taper-matched GP cones. A novel method using a spring balance was designed to quantify the tug-back by measuring the pulling force. The correlation between tug-back scores, pulling force, and percentage of the gutta-percha occupied area (pGPOA) within apical 3 mm was investigated using ${\mu}CT$. The data were analyzed using Pearson's correlation analysis, one-way analysis of variance (ANOVA) and Tukey's test. Results: Specimens with a strong tug-back had a mean pulling force of 1.24 N (range, 0.15-1.70 N). This study showed a positive correlation between tug-back score, pulling force, and pGPOA. However, there was no significant difference in these factors between the PTN and PF groups. Regardless of the groups, pGPOA and pulling force were significantly higher in the specimens with a higher tug-back score (p < 0.05). Conclusions: The degree of subjective tug-back was a definitive determinant for master cone adaptation in the root canal. The use of the tug-back scoring system and pulling force allows the interpretation of subjective tug-back in a more objective and quantitative manner.

• 제어로봇시스템학회논문지
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• 제22권8호
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• pp.615-618
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• 2016

This paper proposes a method to estimate vertical interaction force to the end of the surgical instrument by measuring reaction force at the part supporting the trocar. Relation between the force to the trocar and the interaction force is derived using the beam theory. The vertical interaction force is modeled as a function of the reaction force to the trocar and the distance between the drape plate and the trocar. Experimental results show that error is induced by the asymmetric shape of the trocar tip because contact position between the instrument and the trocar tip is changed depending on the direction of the interaction force. The theoretical relation, therefore, is compensated and reduced. Average $L_2$ relative error of the estimated force in the x-direction and the y-direction is 5.81 % and 5.99 %, respectively.

• 대한기계학회논문집A
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• 제20권7호
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• pp.2213-2222
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• 1996

This paper presents the design process and evaluaation results of a two-axis force transducer for measuring flange reaction forces. A double-cantilever beam structure is used as a sensing element, and its optimal configuration is determined based on the derived strain equations to maximize the sensitivity and minimize the regid body displacements. To reduce the coupling errors between two-axis forces, strain distributions by finite elemetns analysis are utilized and the Wheaststone bridge cricuits composed of strain gages are built such that the output voltage should be zero, although strains of four strain gages are not zero. Calibration test shows that the two-azxis force transducer developed in this paper is useful in measuring flange reaction forces within the coupling error of 5.53%.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(II)
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• pp.898-903
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• 2002

The railroad is a means of large transportation which has many talents such as a safety and a regularity. That is a results from various confidential performance tests and evaluations of the system. The railroad system consist of various subsystems - vehicle, power supply, signal, communications, track structures, operations, etc. Among them, as an item of safety evaluation there is a measurement of wheel/rail force, so called a measurement of derailment coefficient. This is a very important item because a derailment of a train will bring about a big accident. Especially it is more inportant in high speed rail of which operation speed is over two times as fast as existing rail. In this paper, it is introduced to preprocess the wheelset for measuring wheel/rail force of high speed rail, such as to treat a measuring wheelset, its finite element analysis, adhesion of strain gauges and static load test.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 춘계학술대회 논문집
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• pp.762-767
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• 2003

The railroad is a means of large transportation which has many talents such as a safety and a regularity. That is a results from various confidential performance tests and evalutions of the system. The railroad system consist of various subsystems - vehicle, power spply, signal communications, track structures, operations, etc. Among them as an item of safety evaluation there is a measurement of wheel/rail force, so called a measurement of derailment coefficient. This is a very important item because a derailment of a train will bring about a big accident. Especially it is more important in high speed rail of which operation speed is over two times as fast as existing rail. In this paper, it is introduced to preprocess the wheelset for measuring wheel/rail force of Gwangiu EMU, such as to treat a measuring wheelset its finite element analysis, adhesion of strain gauges and static load test.

• 한국공작기계학회논문집
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• 제17권4호
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• pp.75-80
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• 2008

This paper presents an atomic force probe for triggering coordinate measuring machines(CMMs). A rigorous comparison is made between touch trigger probe and atomic force probe for CMMs. Typical CMMs(touch trigger probe based CMMs) often lead to some errors associated with object curvature and difference in triggering sensitivity. Their applicability is limited only to hard objects. The aim of this work is to develop a trigger sensor for CMMs using atomic force. In order to show the applicability of atomic force as a trigger sensor, a cylindrical shape is measured with a CMM and an atomic force microscope. Three different touch probe heads with different ball sizes are tested. The experiments show that smaller ball provides better results for curved objects. The experimental results also show that the performance of atomic force as a trigger sensor is about that of the smallest ball probe. In addition, experiments are also performed to measure soft objects. Finally, this paper suggests and verifies a trigger sensor using atomic force for CMMs.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.1778-1781
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• 1997

The coke oven plant on a steel works has not, in the past, been regarded as a prime user of modern instrument technology. The reason for this perception may be due to the fact that the basic design of the coke battery has been changed little over the years. The recording and analysis of oven pushing force on a routine basis is seen as a means of monitoring plant operation. A torque sensor is set up at the shaft of the rotor for measuring pushing force. Pushing force data which is communicated form torque sensor to staor by telemetry method are shown on MMI(Man-Machine Interface) screen and stored in the database automatically. Perhaps the most important feature is that is allows a problem oven to be identified at an early stage and for corrective action to be taken before it develops into a refusal to push. In this way the mechanical loads imposed on the battery structlure can be held to a necessary minimum, so helping to prolong its service life.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 제35회 춘계학술대회
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• pp.267-271
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• 2002

Most studies of elsatohydrodynamic lubrication are oriented only to the measurement of film thickness itself with optical interferometer. In order to exactly investigate the characteristics of a certain lubricant, it is also important to get the information of traction force as well. In this work, we developed the device for measuring friction force of ehl contact condition together with the film thickness. To verify the validity of the measuring system, the friction force and film thickness under ehl condition are measured with the variation of additive ratios of viscosity index Improvers.

• Journal of Mechanical Science and Technology
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• 제15권6호
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• pp.743-751
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• 2001

A Prototype reaction wheel, named the Hankuk Aviation University (HAU) reaction wheel, has been developed for KAISTSAT satellite series. Torque and force disturbances are inherent in reaction wheels, and thus the force and torque characteristics should be examined for every newly developed reaction wheel. The torque and force disturbance noises in the prototype HAU reaction wheel are measured with a torque-measuring table developed for the present study. A new measuring procedure based on a simple principle is applied for the measurements. The frequency characteristics of the torque and force noises are analyzed by examining the power spectral density. The effect of the torque noise on the attitude stability is also examined through numerical simulations with a single-axis attitude model. The noise-induced attitude error and jitter and found to be well below the specified error limits for the KAISTSAT satellite series.