• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2003년도 추계학술발표논문집
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• pp.209-216
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• 2003

There are two kinds of controllers in a continuous process system. One is for tension control of a moving web and the other for lateral motion control. The inter-connection between tension and lateral behaivior of web has not yet been considered in the analysis of web dynamics and designing of control stragagies. But the effect of tension variation on the lateral motion of a moving web is observed in the most manufacturing systems. In this paper, experimental studies was carried out to find out the inter-correlation between tension and lateral motion of a web using a 3-span web transport system which consists of two displacement type guiders. As a result, it was found that there are typical operating conditions that tension and lateral motion are correlated each other.

• 한국해양공학회지
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• 제20권4호
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• pp.70-75
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• 2006

A numerical procedure is described for estimating the effects of the multi-directional irregular waves on the motion responses and tension variations of the ISSC-TLP. The numerical approach is based on a three-dimensional source distribution method and a spectral analysis technique of directional waves. The spectral description for the linear system of ISSC-TLP in the frequency domain is sufficient to completely define the motion responses and tension variations. This is because both the wave inputs and responses are stationary Gaussian random processes, of which the statistical properties in the amplitude domain are well known. The numerical results for the linear motion responses and tension variations in regular waves are compared with the experimental and numerical ones, which are obtained in the literature. The results of comparison confirmed the validity of the proposed approach.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2002년도 추계학술발표논문집
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• pp.74-80
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• 2002

A mathematical tension model for a moving web in a multi-span web handling system was derived and validated by using a simulator which includes unwinder, driven roller, winder, load cells, controllers, etc. A tension controller was designed to compensate tension disturbances generated by velocity changes of the unwinder and driven roller. From experimental results it was proved that the tension model properly expressed the tension behavior of a moving web for specific conditions. The distributed tension controller designed by using the pole-placement technique compensated the tension disturbances transfered from upsteram tension variation. Interactions between web spans including "tension transfer phenomenon" were clearly confirmed through the study. A mathematical model of lateral motion of a moving web was verified also by using the same experimental apparatus which includes displacement type guidance systems. And a feedforward control strategy was designed for more accurate control of the lateral motion of a moving web, which utilize a measured signal of the lateral displacement of web in a previous span and a more correctly identified mathematical model to estimate the disturbance of lateral motion from the previous span. This approach was turned out to be effective in improving the performance of the guidance system for more wide range disturbances.

• 한국자동차공학회논문집
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• 제5권2호
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• pp.1-12
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• 1997

A computer program was developed to simulate effect of the initial track tension on the tractive performance of tracked vehicles. The performance was evaluated in terms of drawbar pull, motion resistance, tractive coefficient and tractive efficiency. Results of the simulation showed that increase in track tension decreases the sinkage and mean maximum pressure in clay, making the ground pressure distribution more uniform. This tendency became more evident when the number of roadwheels increased. However, such change in MMPs was negligible in firm soils. Motion resistance was also decreased with increase in track tension and the number of roadwheels. Under weak soil conditions, tractive coefficient and efficiency increased generally as the track tension increased for a slip range of 10∼30%. For slippage less than 3∼4%, however, the tractive coefficient decreased with increase in track tension. In general, it was known that increasing track tension improves tractive performance in weak soil conditions. However, high track tension can reduce efficiency due to the increment of internal motion resistance caused by increased track tension.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제14권5호
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• pp.532-536
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• 2008

본 연구는 Laban이 제시한 모션 분석 기법을 이용하여 모션의 긴장도를 측정하는 방법을 제안한다. 이러한 긴장도 값을 이용하면 캐릭터 모션과 배경음악간의 자동적 동기화를 위한 기준값으로 사용할 수 있다. Laban의 모션 분석 기법, 즉 LMA는 모션을 Effort라고 명명된 4개의 시공간적 요소로 나누고 각 4개의 Effort마다 2가지 상반된 기준을 제시함으로써 모션을 분석하도록 하였다. 이러한 기준을 양적으로 측정하기 위해 우리는 운동학, 역학에 기초한 수식을 제안하고 이를 통해서 계산된 실제 긴장도 값을 실험 데이타에 근거하여 조정하였다. 실험을 통해 제안한 긴장도 측정 결과는 어느 정도 사람의 반응과 비슷한 정도의 순위 판별 능력을 보였다.

• The Journal of Korean Physical Therapy
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• 제21권2호
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• pp.71-77
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• 2009

Purpose: This study assessed the differences in the forward head posture (FHP), cervical range of motion, and headache clinical parameters in episodic tension-type headache (ETTH) subjects, chronic tension-type headache (CTTH) subjects, and healthy controls (university students). Methods: Fifteen CTTH subjects, 15 ETTH subjects and 15 controls without headache were examined. Side-view images of each group were taken in both the sitting and standing positions, in order to assess the FHP by measuring the craniovertebral angle. The CROM was used to measure the cervical range of motion. A headache diary was kept for 4 weeks to assess the headache intensity, frequency, and duration. Results: The craniovertebral angle was smaller, ie, there was a greater FHP, in the CTTH and ETTH subjects than in the healthy controls in both the sitting and standing positions (p<0.05). The CTTH and ETTH subjects showed a lower cervical range of motion than the healthy controls in the total range of motion as well as in the half-cycles (p<0.05). Conclusion: The increased FHP and decreased cervical range of motion might be a contributing factor in the initiation of tension-type headache.

• 제어로봇시스템학회논문지
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• 제9권12호
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• pp.994-1000
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• 2003

A new relative motion control methodology for a following system to an independent leading system is proposed for controlling relative position, velocity, and tension etc. It is based on maintaining minimum relative error between two independent systems. The control command of the following system to a leading system is generated by adding the current command and the output of the relative error compensation. The proposed control method is implemented on the experimental equipment which is a wire winding-unwinding system to control the tension of the line. The results show the unwinding system(follower) following the independent motion of the winding system(leader) to control the constant tension of the line in order to keep the roller dancer in reference position. The relative motion control method proposed in this paper can be applied to high precision equipment for unwinding and winding fine wire, fine fiber, and tape etc.

• 한국정밀공학회지
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• 제19권3호
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• pp.95-100
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• 2002

Built-in Eccentric Bearing-Torsional Spring (BEBTS) type Automatic Belt Tension Unit (ABTU) is one of typical belt tension units. The BEBTS type ABTU system frequently experiences torsional vibration about its pivot due to the variation of belt tension. However, it is very difficult to analyze the rotational (or torsional) vibration of the ABTU because the exciting moment varies according to the change of belt tension. To get over this difficulty, in this paper. the ABTU was simplified as 1-DOF translational motion model in the tangential direction. Its equation of motion was derived and solved. The time history and frequency responses were computed and examined for three of BEBTS type ABTUs which are made by different manufacturers but the tame kind.

• 한국항해항만학회지
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• 제44권5호
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• pp.363-374
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• 2020

In the past, various research on the effects of waves generated by ships has been investigated. The most noticeable effect of the waves generated by a passing ship is the increase of the hydrodynamic forces and the unwanted large motion of the moored ship and high mooring forces that occur. Thus, it is crucial to investigate the effect of the waves generated by the passing ship near port on the motion of the moored ship and the tension of the mooring lines. A model test was performed with virtual ship-generated waves in a square tank at CWNU (Changwon National University). The IMU (Inertial Measurement Unit) and Optical-based system were used to measure the 6DOF (Six Degrees of Freedom) motion of the moored floater. Additionally the tension of mooring lines were measured by the tension gauges. The effects of the wave direction and wave height generated by the virtual ship-generated waves on the motion of the moored floater were analyzed.

• 풍력에너지저널
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• 제14권2호
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• pp.26-33
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• 2023

In this study, the global response characteristics of floater and mooring for floating offshore wind turbine with a detachable mooring system are performed. Global motion and structural response result extracted from the coupled motion analysis of 10MW DTU floating offshore wind turbine with detachable mooring system modeled by high-order boundary element model and finite element mesh, were used to study the characteristics of tension on mooring lines subjected to three different types of ocean loads. Breaking limit of mooring line characterized by wind, current and wave load has a major effect on the distribution of mooring tension found in time domain analysis. Based on the numerical results of coupled motion analysis, governing equation for calculating the motion response of a floater under ocean loads, and excitation force and surge motion and tension respectively are presented using excursion curve. It is found that the response of floater is reliable and accurate for calculating the tension distributions along the mooring lines under complex loadings. This means that the minimun breaking limit of mooring system satisfied a design criteria at ultimate ocean environmental loading condtions.