• The Transactions of the Korean Institute of Electrical Engineers
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• v.32 no.8
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• pp.277-283
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• 1983

The pulse generating circuit system of the so-called turbulently-heated theta pinch is experimentally investigated, and its results are compared with the predictions based on the conventional theory. The conventional theory assumes that the impedance of the pinch coil is independent on the time rate of change in voltage (or current) across the pinch coil. The experimental pulse height of the voltage actross the pinch coil is about 1.5% fo that predicted by the conventional theory.

• Transactions of the Korean hydrogen and new energy society
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• v.26 no.6
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• pp.590-599
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• 2015

In this paper a performance analysis is carried out based on the first and second laws of thermodynamics for heat exchanger in organic Rankine cycle (ORC) for the recovery of low-temperature finite thermal energy source. In the analysis, effects of the selection of working fluid and pinch temperature difference are investigated on the performance of the heat exchanger including the effectiveness of the heat exchanger, exergy destruction, second-law efficiency, number of transfer unit (NTU), and pinch point. The temperature distribution are shown depending on the working fluids and the pinch temperature difference. The results show that the performance of the heat exchanger depends on the pinch temperature difference sensitively. As the pinch temperature increases, the exergy destruction in the evaporator increases but the effectiveness, second law efficiency and NTU decreases.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.2
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• pp.1201-1216
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• 2017

In this study, we described the development of a methodology to measure tip-pinch strength on the paretic hand rehabilitation device and aimed to investigate reliability of the device. FSR sensors were embedded on the device, and tip pinch strength was estimated with data collected from the sensors using a developed equation while participants were demonstrating tip pinch. Reliability tests included inter-rater, test-retest, and inter-instrument reliability. B&L Engineering pinch gauge was utilized for the comparison. Thirty-seven healthy students participated in the experiment. Both inter-rater and test-retest reliability were excellent as Intraclass Correlation Coefficients (ICCs) were greater than 0.9 (p<0.01). There were no statistically significant differences in tip-pinch strengths. Inter-instrument reliability analysis confirmed good correlation between the two instruments (r = 0.88, p < 0.01). The findings of this study suggest that the two instruments are not interchangeable. However, the tip-pinch mechanism used in the paretic hand rehabilitation device is reliable that can be used to evaluate tip pinch strength in clinical environment and can provides a parameter that monitors changes in the hand functions.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.6
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• pp.799-807
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• 1999

Exergy analysis is widely used in energy system analysis for more efficient energy use. Pinch technology has focused on chemical plants, such as pure heat exchanger networks. In this study, the objective is to seek more effective means with integrating above two methods. In order to demonstrate effective result and to prove possibility for pinch analysis, the steam turbine is adopted to make heat recovery in the heat exchanger network. Three cases are introduced using the integration of exergy and pinch analysis. The standard steam turbine utility is the base case, and adding the heat pump to this system is the second case. The third case is the system with the heat pump and minimum utilities. The results show that the output power of steam turbine in the case(2) and case(3) are increased up to 42% and 46%, respectively, compared with that of base case.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.3
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• pp.788-795
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• 1996

In this paper, and optimum profile of a cam being used in a VTR Deck mechanism is designed by the response surface analysis. The objective function of the design is to reduce driving torque of the pinch roller system that is used to compress video tape to the capstan motor axia. The pinch roller system that will be designed is modeled using the general purpopse mechanism analysis program DADS. The computer model is compared with the physical system for reliability. A model function to represent relationship between design variables and the objective function is estimated by the response surface analysis. Once the model function is reliably estimated the optimal design is carried out using the model function and each design variable's boundaries. To verify improvement of the pinch roller system, a prototype for the pinch rooler system is made and tested. From the test result, an optimum cam profile to resuce driving torque of the pinch roller system is verified.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.2526-2531
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• 2005

A practical pinch torque estimator based on the Kalman filter is proposed for low-cost anti-pinch window control systems. To obtain the accurate angular velocity from Hall-effect sensor measurements, the angular velocity calculation algorithm is executed with additional procedures for removing the measurement noises. Apart from the previous works using the angular velocity estimates and torque estimates for detecting the pinched condition, the torque rate is augmented to the system model and the proposed pinch estimator is derived by applying the steady-state Kalman filter recursion to the model. The motivation of this approach comes from the idea that the bias errors in torque estimates due to the motor parameter uncertainties can be almost eliminated by introducing the torque rate state. For detecting the pinched condition, a systematic way to determine the threshold level of the torque rate estimates is also suggested via the deterministic estimation error analysis. Simulation results are given to certify the pinch detection performance of the proposed algorithm and its robustness against the motor parameter uncertainties.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1588-1593
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• 2008

This paper describes a real-time isometric pinch force prediction algorithm from surface electromyogram (sEMG) using multilayer perceptron (MLP) for human robot interactive applications. The activities of seven muscles which are observable from surface electrodes and also related to the movements of the thumb and index finger joints were recorded during pinch force experiments. For the successful implementation of the real-time prediction algorithm, an off-line analysis was performed using the recorded activities. Four muscles were selected for the force prediction by using the Fisher linear discriminant analysis among seven muscles, and the four muscle activities provided effective information for mapping sEMG to the pinch force. The MLP structure was designed to make training efficient and to avoid both under- and over-fitting problems. The pinch force prediction algorithm was tested on five volunteers and the results were evaluated using two criteria: normalized root mean squared error (NRMSE) and correlation (CORR). The training time for the subjects was only 2 min 29 sec, but the prediction results were successful with NRMSE = 0.112 ${\pm}$ 0.082 and CORR = 0.932 ${\pm}$ 0.058. These results imply that the proposed algorithm is useful to measure the produced pinch force without force sensors in real-time. The possible applications include controlling bionic finger robot systems to overcome finger paralysis or amputation.

• Journal of the Korean Society of Physical Medicine
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• v.4 no.4
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• pp.275-280
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• 2009

Purpose：We have investigated to analysis biomechanics for pinch strength due to elbow flexion degree. Methods：Pinch strength was measured by Electro Dynamometer(G-100) using four elbow flexion degree ($0^{\circ}$, $45^{\circ}$, $90^{\circ}$, $135^{\circ}$). Results：In experimental results, we found that pinch strengths were 5.4kg($0^{\circ}$), 4.8kg($45^{\circ}$), 5.6kg($90^{\circ}$) and 5.2kg($135^{\circ}$), respectively. The Pinch strengths got maximum at $90^{\circ}$ degree, minimum at $45^{\circ}$ degree. We have calculated F1 values using $\sum$T=0. As a result F1 values were 540N($0^{\circ}$), 480N($45^{\circ}$), 560N($90^{\circ}$) and 520N($135^{\circ}$), respectively. F1 values got maximum at $90^{\circ}$ degree, minimum at $45^{\circ}$ degree. Data curve line of $F_1$ values was increased in 45~90 section and decreased in 0~45, 90~135 sections, respectively. Conclusion：$F_1$ (Flexor digitorum superficialis and profundus) values were 10 times bigger than pinch strengths. Data curve line of $F_1$ values was similar to active length-tension curve in 45~90, 90~135 sections.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.6
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• pp.657-682
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• 2011

This paper presents the dynamic analysis on the joint torque of a finger for the tip pinch task. The dynamic model on finger movement was developed in order to predict the joint torques of an index finger, and the finger was assumed as a three-link planar manipulator. Analysis of the model revealed that the joint stiffness was one of the most important parameters affecting the joint torque. The stiffness of the finger joint was experimentally measured, and it was used in analyzing the finger joint torque required for performing the tip pinch task. The obtained joint torque for the tip pinch task will be used as the design requirements of the finger exoskeletal orthosis actuated by the polymer actuator whose allowable torque limit is relatively low compared to that of a mechanical actuator.

• Journal of Power System Engineering
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• v.21 no.5
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• pp.63-70
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• 2017

This paper deals with anti-pinch system based on current information which prevents some risks for trapping, squeezing or injury to people in smart window on vehicles. Automatic configuration of current threshold is suggested to recognize pinch states in the current based anti-pinch system. Also, some factors affecting to the squeezing force were analyzed by some experimental results and simulations. The validity of the suggested system was verified to satisfy the strengthened American safety regulation, FMVSS 118-S5, through some experimental results.