• The Journal of Korean Physical Therapy
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• v.14 no.1
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• pp.117-124
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• 2002

Poor posture of the neck and head long been recognized as a factor contributing to the onset and perpetuation of pain in the head and neck region. The purposes of the study were to evaluate the changes in forward head posture and pressure pain threshold in tension type headache group and control group. Forward head posture were measured to craniovertebral angle and cranial rotation angle. Craniovertebral angle was smaller in tension type headache group(p<0.05), and cranial rotation angle was larger in tension type headache group(p<0.05). Pressure pain threshold was similar between tension type headache group and control group with the exception of right suboccipitalis and left temporalis(p<0.05).

• Tribology and Lubricants
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• v.12 no.4
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• pp.7-12
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• 1996

Present study was undertaken to investigate the leakage and friction of self-lubricating piston seal rings. A crank-piston type gas leakage test set-up was constructed. The piston rings were made of PTFE-polyimide composite. The free gap configurations of the seal rings were butt and step types. Eccentric tension rings were used to give the seal rings prepressure between the seal rings and cylinder wall. Two sizes of the tension rings were installed to investigate their effect on the gas leakage and friction of the seal rings. The results showed that step type seal rings are superior than the butt types. High tension spring rings resulted in low leakage and high friction loss. In order to reduce the gas leakage and friction loss of the piston seal rings, there should be compromise between the number of ring stages and prepressure of the tension rings.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.340-343
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• 2004

The cement-based composites have been used for construction industry because of their economy, suitability for architecture and structure function, fire resistance, low fee of repair, easiness for acquisition. but the limited strain capacity of these makes them tension-weak, brittle, and considerable notch-sensitive. As one of solution, FRC(fiber reinforced concrete) have been investigated for regulating weakness of the cement-based composites. In these day different fiber types are proposed for better performance such as HFRC(hybrid fiber reinforced concrete). This study shows experimental results to search the ultimate strength, the ultimate mean strain, and the tension toughness of HFRC. The tension toughness is proportional to the amount of steel fiber and carbon fiber. In this experimental program we kept the total of steel fiber and carbon fiber as $1.0\%,\;1.5\%$, respectively.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.438-441
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• 2004

This paper presents the results of the experimental study on the performances of reinforced concrete beams rehabilitated by external unbonded high tension steel-bar. Design variables for the experiment in this study includes the position of anchorage zone of the high tension steel bar, the anchorage length of the reinforcing steel bar and the types of the shear strengthening measures. 5 specimens were tested with one point monotonically increased loads and structural performances such as strength capacities, ductility capacities and failure modes were analysed. It is found that the structural performance of the rehabilitated beams are strongly depended on the location of anchorage zone of the high tension steel-bars. In the case that anchorage zone is located near the critical shear zone, it is observed that the rehabilitated beam is failed in brittle failure mode and the additional shear strengthening is necessitated. But if anchorage zone is properly located or additional shear strengthening device is provided properly, it is also observed that the strength capacity of the rehabilitated beams could be increased more than $200\%$ by the proposed method.

• International Journal of Concrete Structures and Materials
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• v.10 no.2
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• pp.143-147
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• 2016

In recent years, some modifications were introduced in the stress-strain relationship of the steel in order to develop a more efficient shear model for reinforced concrete members. The last contribution in this sense corresponding to the Refined Compression Field Theory (RCFT, 2009); this theory proposed a steel constitutive model that has account the tension stiffening area prescribed by technical codes, what simplifies all the design process. However, under certain design conditions supported by such codes, the RCFT model does not provide a real (non-complex) solution for the steel yield strain when the prescribed tension stiffening area is considered; then the load-strain response cannot be computed. In this technical note, the tension stiffening area is fixed in order to guarantee the application of the embedded steel constitutive model for all the standard design range.

• Journal of Ocean Engineering and Technology
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• v.20 no.5 s.72
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• pp.36-41
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• 2006

The main object of this study is to develop an accurate and convenient method for the response analysis of offshore structures in real sea states. A numerical procedure is described for predicting the motion responses and tension variations of the ISSC TLP in multi-directional irregular waves. The developed numerical approach in the frequency domain is based on acombination of the three dimensional source distribution method, the dynamic response analysis method, and the spectral analysis method. Frequency domain analysis in the multi-directional irregular waves is expanded to a time domain analysis by using a convolution integral after obtaining the impulse response by Fourier transformation. The results of the comparison between responses in the frequency and time domain confirmed the validity of the proposed approach.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.6
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• pp.1239-1244
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• 2011

In our previous paper, we developed an insulator inspection robot system for a suspension insulator string in the 345kV power transmission line. However, this robot cannot be applied to a tension insulator string, because its constituent insulators are different in diameter and height from those of a suspension insulator string. To solve this problem, we developed a new live-line insulator inspection robot system that is applicable to both suspension and tension insulator strings. We confirmed its effectiveness through live-line performance tests.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.5
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• pp.99-107
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• 2003

In a winding process, important control specifications include regulation of web tension and velocity. In this research, an adaptive controller has been developed for controlling web tension and velocity in winding processes. For the controller design, the linear quadratic regulator theory has been adopted and a gain-scheduling scheme has been incorporated. A prototype winding system has been constructed, and the controller has been implemented in a real-time PC-based environment. The performance of the closed loop system has been evaluated via simulation and experiments, and it was observed that both the web tension and velocity could be regulated within a small tolerance.

• Journal of Life Science
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• v.8 no.4
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• pp.373-380
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• 1998

A considerable change observed in X-ray diffraction during the muscle contraction was that the movement of myosin head and conformational change of contractile monecules were occurred in the muscle contraction. Time slice requires tension peak after the onset of stimulation and the height of tension peak depends on the number of twitch cycle. The intensity of I$_{11}$, I$_{10}$, 143${\AA}$ reflection is measured with 5ms time resolution and is recorded in isometric tension. The peak height of I$_{11}$ and 143${\AA}$ intensity is changed after the onset of a stimulation I$_{i}$, and the length of twitch is shortened by successive twitches in the case of stimulation TI$_{i}$. On the other hand, the peak height of I$_{11}$ and 215${\AA}$ intensity starts to decrease at the 1st twitch and remains constant at low peak hight without appreciable recovery during the contraction term. In the case of uccessive twitch stimulation, the myosin heads of muscle are once moved from their resting position and never returned to their initial position.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.1
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• pp.46-56
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• 2008

A numerical model analysis was performed to analyze the motion and mooring tension response of submersible fish cage systems in irregular waves and currents. Two systems were examined: a submersible cage mooring with a single, high tension mooring and the same system, but with an additional three point mooring. Using a Morison equation type model, simulations of the systems were conducted with the cage at the surface and submerged. Irregular waves(JONSWAP spectrum) with and without a co-linear current with a magnitude of 0.5m/s were simulated into the model as input parameters. Surge, heave and pitch dynamic calculations were made, along with tension responses in the mooring lines. Results were analyzed in both the time and frequency domains and linear transfer functions were calculated.