• 해양안보
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• 제3권1호
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• pp.1-44
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• 2021

중국의 새로운 해양정책법(Maritime Policy Law: MPL)은 중국해안경비대 등의 중국 해양경찰 기관들의 임무를 규제하고, 중국의 주권, 안보, 권리, 이해관계를 보호한다고 주장한다. [하지만] 중국이 본토 주위 및 남중국해에서 넓은 해역에 대한 권리를 주장하고 있다는 점에서, MPL은 훨씬 광범위하게 적용될 수 있다. 중국이 제기하는 대부분의 해양 주장이 국제법에 부합하지 않는다는 점을 고려하면, 이렇게 해양법 집행 관할권을 광범위하게 적용하는 것은 문제의 소지가 많다. MPL이 분쟁해역 또는 공해에서 외국선적 선박에 대한 관할권을 주장한다면, 이는 국제법 위반이다. 무력 사용에 관한 MPL의 많은 규정 역시, 해양법 집행 관할권의 사용에 관한 국제 규칙 및 기준을 위반한 것이며, 모든 국가의 영토 온전성이나 정치적 독립성에 반하는 위협이나 무력사용을 금하는 유엔헌장에도 위배된다. 중국은 MPL을 남중국해와 동중국해에서 불법적인 영토 및 해양 주장을 제기하기 위한 구실로 사용할 수 있으며, 다른 연안국의 배타적경제수역 내 자원 권리 행사를 방해하기 위한 구실로도 사용할 수 있다.

• 한국정밀공학회지
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• 제22권1호
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• pp.32-38
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• 2005

Generally, cutting force models use a sin function method to calculate chip thickness. In slot end milling, the error from a sin function method is much bigger than other machining because a tool rotation angle in cutting is much larger. Thus in this paper, a new method to calculate chip thickness was suggested and evaluated. In a new method, tool position data according to tool rotation are checked and stored so that it is possible correct chip thickness is calculated. Cutting force waveforms simulated from a sin function method and a new method and measured waveforms from experiments were compared and error percentages were obtained. Finally, a new method had good results for simulating cutting force in slot end milling.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 춘계학술대회논문집
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• pp.169-172
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• 2004

This paper proposes a new MR(magneto-rheological) brake utilizing composite modes of MR fluid. Its basic structure and design scheme are almost the same with the conventional MR brake, but for slots in a rotating disk or shell. The slots enable the proposed MR brake to use a new mode, so-called, ‘direct cutting chain mode’as well as shear mode, which results in increasing the braking force(almost 150% compared to the case without slots). Some experimental results show that the proposed MR brake provide the sufficient braking force to be adopted for small portable force feedback devices.

• Journal of Oral Medicine and Pain
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• 제10권1호
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• pp.63-71
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• 1985

A kinematical study of bite force during voluntary isometric contraction was investigated in 20 Korean men with TMJ dysfunction and 30 Korean men as normal subject, ranging from 20 to 27 years old. The author observed maximum bite force, slope of bite force graph, curve index and duration of maximum bite force with the use of the foil strain gauge (MPM-3000) and RS Dymograph (Beckman). The obtained results were as follows : 1. Maximum bite forces were 29kg and 29kg for left and right side of normal subject (p>0.05) and 19kg and 29kg for affected and non-affected side of TMJ dysfunction patient. 2. The slopes of bite force graph were $68^{\circ}$ and $68^{\circ}$ for left and right side of normal subject (p>0.05) and $59^{\circ}$ and $71^{\circ}$ for affected and non-affected side of TMJ dysfunction patient. (p<0.01) 3. The curve indices were 0.93 and 0.90 for left and right side of normal subject and 1.10 and 0.90 for affected and non-affected side of TMJ dysfunction patient. (p>0.05) 4. The durations of maximum bite force were 424 msec and 413 msec for left and right side of normal subject and 337 msec and 334 msec for affected and non-affected side of TMJ dysfunction patient. (p>0.05)

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 1998년도 추계학술대회 학술발표 논문집
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• pp.568-576
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• 1998

In this thesis discuss with a flexible robotic finger design and controller which is used for the micro flexible robotic finger. So, miniaturization, precision, controller for the control of grasping force and actuator were needed. And, even if we develop a new actuator and controller, in order to use on real system, we must considerate of a many side problem. In a force control of micro flexible finger for grasping an object, the fingertip's vibration was more important task of accuracy control. And, controller were adopt the PD/PI mixed type fuzzy controller. The controller were consist of two part, one is a PD type fuzzy controller for increase the rising time response, the other is a PI type fuzzy controller for decrease of steady-state error. Especially, in a PD type fuzzy controller, we used only seven rules. And, for a PI controller, we adopt a reset factor for the control of input values. so, we have overcome the exceed of controller's input range. For the estimate of ontroller's utility and usefulness, we have experiment and computer simulation of three cases. First, we consider of unit force grasping control for a task object, which is 0.03N. Second, bounding grasping force control which is add to a sinusoidal force on the unit force. At this cases the task force is (0.03+0.01 sin wt N). And consider of following of rectangular forces.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.637-640
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• 2005

In this paper, we investigate the characteristics of a piezoresistive AFM cantilever in the range of $0\~30{\mu}N$ by using nano force calibrator (NFC), which consists of a high precision balance with resolution of 1 nN and 1-D fine positioning stage. Brief modeling of the cantilever is presented and then, the calibration results are shown. Tests revealed a linear relationship between the probing force and sensor output (resistance change), and the force vs. deflection. From this relationship, the force constant of the cantilever was calculated to 3.45 N/m with a standard deviation of 0.01 N/m. It shows that there is a big difference between measured and nominal spring constant of 1 N/m provided by the manufacturer s specifications.

• 대한기계학회논문집
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• 제17권8호
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• pp.1951-1962
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• 1993

The creation process of a typical machined surface is treated here as a dynamic system. An investigation is carried out to establish a relationship between the characteristics of cutting force fluctuations that cause vibration response of the tool-workpiece system and the formation of surface in face cutting by sintered carbide cutting tool. Cutting force is measured and analyzed in frequency domain. The power spectral densities of cutting force give a useful information in surface generation and it can be used to find out the control factor of surface roughness. The terms, PSD ratio & Normalized spindle frequency PSD, are defined and when the value of power in spindle frequency is absolutely little but relatively large, it is obtained high accuracy surface roughness. The aim of this research is to find surface profile by measured and analyzed cutting force signals. The simulation of surface generation gives the comprechension of its mechanism and help to predict and control the surface quality. In this study, it is suggested what informations about surface generation can be acquired from the cuttuing force signal and an way of generating a better surface.

• KIEE International Transactions on Electrophysics and Applications
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• 제5C권6호
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• pp.264-269
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• 2005

The electrostatic comb drive actuator is one of the main building blocks in the field of micro electro-mechanical systems (MEMS). Most of the comb actuators presented previously have fingers that are rectangular in shape which produce a stable, constant force output during actuation. The use of sawtooth fixed fingers in a comb drive, which were presumed to produce an increasing force output with displacement due to the increased number of regions where fringing force, the driving force of comb actuators, appear. The dimensions of the sawtooth were derived from finite element analysis (FEA) of simplified finger models with sawtooth type fingers of various dimension and were compared to the rectangular finger model that showed that the sawtooth type fingers have $7\~9$ times stronger driving force. Finally, comb drive actuators with sawtooth type and rectangular fingers were fabricated and although the gap was bigger, the comb actuator with sawtooth type fingers showed about 1.7 times greater electrostatic force than the one with rectangular fingers at equal driving voltages. In conclusion, using the proposed sawtooth type comb fingers in a comb drive makes it possible to increase its displacement or reduce the driving voltage.

• Wind and Structures
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• 제18권4호
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• pp.347-373
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• 2014

Since its development in the early 1980's the force balance technique has become a standard method in the efficient determination of structural loads and responses. Its usefulness lies in the simplicity of the physical model, the relatively short records required from the wind tunnel testing and its versatility in the use of the data for different sets of dynamic properties. Its major advantage has been the ability to provide results in a timely manner, assisting the structural engineer to fine-tune their building at an early stage of the structural development. The analysis of the wind tunnel data has evolved from the simple un-coupled system to sophisticated methods that include the correction for non-linear mode shapes, the handling of complex geometry and the handling of simultaneous measurements on multiple force balances for a building group. This paper will review some of the components in the force balance data analysis both in historical perspective and in its current advancement. The basic formulation of the force balance methodology in both frequency and time domains will be presented. This includes all coupling effects and allows the determination of the resultant quantities such as resultant accelerations, as well as various load effects that generally were not considered in earlier force balance analyses. Using a building model test carried out in the wind tunnel as an example case study, the effects of various simplifications and omissions are discussed.

• 센서학회지
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• 제20권5호
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• pp.351-356
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• 2011

Stroke patients should exercise for the rehabilitation of their fingers, because they can't use their hand and fingers. Their hand and fingers are fixed on the hand fixing system for rehabilitation exercise of them. But the hands clenched the fist of stroke patients are difficult to fix on it. In order to fix the hands and fingers, their palms are pressed with pressing bars and are controlled by reference force. The fixing system must have a five-axis force/moment sensor to force control. In this paper, the five-axis force/moment sensor was developed for the hand fixing system of finger-rehabilitation exercising system. The structure of the five-axis force/moment sensor was modeled, and designed using finite element method(FEM). And it was fabricated with strain-gages, then, its characteristic test was carried out. As a result, the maximum interference error is less than 2.43 %.