• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
• /
• 2003.11a
• /
• pp.209-216
• /
• 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.

• Journal of Ocean Engineering and Technology
• /
• v.20 no.4 s.71
• /
• pp.70-75
• /
• 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.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
• /
• 2002.11a
• /
• pp.74-80
• /
• 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.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.5 no.2
• /
• pp.1-12
• /
• 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.

• Journal of KIISE:Computing Practices and Letters
• /
• v.14 no.5
• /
• pp.532-536
• /
• 2008

In this paper, we propose the method to measure tensions of character motions, using LMA (Laban Movement Analysis). Using tension values, we tan take advantage of them as a standard for synchronization of motion and BGM(Back Ground Music). In LMA, a motion is divided into 4 space-time factors which are called Efforts, and each Effort has two bases opposed to each other. We can analyze the motion by justifying which basis is stronger than the other in each Effort of motion. To measure quantitatively tension values, we propose some equations based on kinematics and dynamics. Then we can measure the tension value by the weighted sum of values calculated from those equations. Each weight can be determined by the optimization process which tries to minimize the difference between the calculated tension value and human's decision. The experimental result shows that the in creasing order of the motion tension value is similar to that of the tension score given by human.

• The Journal of Korean Physical Therapy
• /
• v.21 no.2
• /
• pp.71-77
• /
• 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.

• Journal of Institute of Control, Robotics and Systems
• /
• v.9 no.12
• /
• pp.994-1000
• /
• 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.

• Journal of the Korean Society for Precision Engineering
• /
• v.19 no.3
• /
• pp.95-100
• /
• 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.

• Journal of Navigation and Port Research
• /
• v.44 no.5
• /
• pp.363-374
• /
• 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.

• Journal of Wind Energy
• /
• v.14 no.2
• /
• pp.26-33
• /
• 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.