• Structural Engineering and Mechanics
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• v.43 no.5
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• pp.623-636
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• 2012

The aim of the current work is to describe the flexural behaviour of simply supported concrete beams with tension reinforcement spliced at mid-span. The parameters included in the study were the type of the concrete, the splice length and the configuration of the hooked splice. Fifteen beams were cast using an ordinary concrete mix and two fiber reinforced concrete mixes incorporating steel and polypropylene fibers. Each concrete mix was used to cast five beams with continuous, spliced and hooked spliced tension steel bars. A test beam was reinforced on the tension side with two 12 mm bars and the splice length was 20 and 40 times the bar diameter. The hooked bars were spliced along 20 times the bar diameter and provided with 45-degree and 90-degree hooks. The test results in terms of cracking and ultimate loads, cracking patterns, ductility, and failure modes are reported. The results demonstrated the consequences due to short splices and the improvement in the structural behaviour due to the use of hooks and the confinement provided by the steel and polypropylene fibers.

• Ocean Systems Engineering
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• v.9 no.3
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• pp.219-240
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• 2019

This paper presents the comparison between SFT response with linear and nonlinear cables. The dynamic response analysis of submerged floating tunnel (SFT) is presented computationally with linear and nonlinear tension legs cables. The analysis is performed computationally for two wave directions one at 90 degrees (perpendicular) to tunnel and other at 45 degrees to the tunnel. The tension legs or cables are assumed as linear and non- linear and the analysis is also performed by assuming one tension leg or cable is failed. The Response Amplitude Operators (RAO's) are computed for first order waves, second order waves for both failure and non-failure case of cables. For first order waves- the SFT response is higher for sway and heave degree of freedom with nonlinear cables as compared with linear cables. For second order waves the SFT response in sway degree of freedom is bit higher response with linear cables as compared with nonlinear cables and the SFT in heave degree of freedom has higher response at low time periods with nonlinear cables as compared with linear cables. For irregular waves the power spectral densities (PSD's) has been computed for sway and heave degrees of freedom, at $45^0$ wave direction PSD's are higher with linear cables as compared with nonlinear cables and at $90^0$ wave direction the PSD's are higher with non-linear cables. The mooring force responses are also computed in y and z directions for linear and nonlinear cables.

• Proceedings of the Korea Concrete Institute Conference
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• 1990.04a
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• pp.102-107
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• 1990

The research program is directed at studying the behavior and the strength of reinforced concrete slabs subjected to certain combination of punching shear and in-plane tension. Major variables to be investigated are the shear span to depth ratio of reinforced concrete slabs and the degree of the in-plane tensile force which is acting tangent to the slabs. The experimental results are used for understanding of the degree of the interaction between the two loadings, and for developing a new practical design equation.

• Journal of Mechanical Science and Technology
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• v.16 no.12
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• pp.1604-1612
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• 2002

Rollers in the continuous process systems are ones of key components that determine the quality of web products. The condition of rollers (e.g. eccentricity, runout) should be consistently monitored in order to maintain the process conditions (e.g. tension, edge position) within a required specification. In this paper, a new diagnosis algorithm is suggested to detect the defective rollers based on the frequency analysis of web tension signals. The kernel of this technique is to use the characteristic features (RMS, Peak value, Power spectral density) of tension signals which allow the identification of the faulty rollers and the diagnosis of the degree of fault in the rollers. The characteristic features could be used to train an artificial neural network which could classify roller conditions into three groups (normal, warning, and faulty conditions) The simulation and experimental results showed that the suggested diagnosis algorithm can be successfully used to identify the defective rollers as well as to diagnose the degree of the defect of those rollers.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.12
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• pp.107-114
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• 2000

Rollers and rolls in the continuous process systems are noes of key components that determine the quality of web products. The condition of rollers and rolls(ex. eccentricity wear) should be consistently monitored in order to maintain the process conditions (ex. tension, edge position) within a required specification. In this paper, a new diagnosis technique is suggested to detect the defect of rollers/rolls (ex. eccentricity, wear) based on frequency domain analysis of web tension signal. The kernel of this technique is to use the spectrum amplitude of tension signal which allows to identify the fault rollers/rolls and to also diagnose the degree of fault in corresponding rollers and rolls. The experimental results proved that the suggested diagnosis technique can be successfully used to identify the defect rollers and rolls as well as to diagnose the degree of the defect of those rollers. The suggested technique can be applied to monitor and diagnose the shape of rollers and rolls in various multi-span web transport systems.

• The Journal of Korean Medicine
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• v.19 no.2
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• pp.100-111
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• 1998

This study is designed to investigate the effects of Saengmaegsan extract on cultured myocardial cell sheets affected by oxygen tension change. The results were as follows : 1. Saengmaegsan meaningfully restored the cellular activity decrease in the cultured myocardial cells affected by high oxygen tension. 2. Saengmaegsan meaningfully lessened the degree of total protein decrease in the myocardial cells caused by high oxygen tension. 3. Saengmaegsan meaningfulJy refrained from syntetic decrease of 4-hydroxyproline in both low oxygen tension group and high oxygen tension group.

• Journal of Chest Surgery
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• v.22 no.6
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• pp.901-913
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• 1989

This study was investigated under the postulation that activation of intracellular calcium- calmodulin complex during ischemia-reperfusion leads to myocardial injury. The protective effects of calcium channel blocker, diltiazem and calmodulin inhibitors, trifluoperazine, flunarizine and calmidazolium from ischemic injury in rat hearts were observed by using Langendorff apparatus when the antagonists were infused for 3 min in the beginning of ischemia. Thereby, an increase in resting tension developed during 30-min ischemia was analyzed with regard to [1] the degree of cardiac functional recovery following 60-min reperfusion, [2] changes in biochemical variables evoked during 30-min ischemia. The results obtained were as follows: l. In the ischemic group, the resting tension was increased by 4.1*0.2 g at 30-min ischemia. However, the increase in resting tension was markedly reduced not only by pretreatment with diltiazem [3.3 p M] but also with calmodulin inhibitors, trifluoperazine [3.3 p M], flunarizine [0.5 p M] and calmidazolium [0.5 p M], respectively. 2. Recovery of myocardial contractility, +dF /dt and coronary flow were much reduced when evoked by reperfusion in the ischemic group. These variables were significantly improved either by pretreatment with diltiazem or with calmodulin inhibitors. 3. The resting tension increment evoked during ischemia was significantly inversely correlated with the degree of cardiac function recovered during reperfusion. 4. Following 30-min ischemia, the production of malondialdehyde and release of lysosomal enzyme were much increased in association with a decrease in creatine kinase activity. 5. The increases in malondialdehyde production and release of free lysosomal enzyme were suppressed by pretreatment with calmodulin inhibitors as well as diltiazem. Likewise, the decrease of creatine kinase activities was prevented by these calcium antagonists. With these results, it is indicated that a increase in resting tension observed during ischemia has an inverse relationship to the cardiac function recovered following reperfusion, and further, the later may be significantly dependent on the degree of biochemical alterations occurred during ischemia such as decrease in creatine kinase activity, increased production of malondialdehyde and increased release of free lysosomal enzyme. Thus it is concluded that calmodulin plays a pivotal role in the process of ischemic injury.

• Journal of Biomedical Engineering Research
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• v.20 no.2
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• pp.191-198
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• 1999

Biofeedback training is one of physiological self control methods for patients who has psychological problem and rehabilitational problem. It has been used to control blood pressure, heart rate, peripheral temperature, respiration, electromyography (ENG), and other biological signals-ENG, respiration, heat rate, peripheral temperature, skin conductance level-was developed in house. We applied this system to alcohol dependent patients to perform biofeedback training. In this experiment, the relaxation biofeedback training for alcohol dependent patient was carried out and the tension state for the change of biological signals were estimated using the fuzzy theory after relaxation biofeenback training. Eight alcohol dependent patients were agreed to participate in this experiment. Result showed that 1) the tension degree of patients were higher than the tension degree of normal subject. 2) The tension degree of patients were decreased as the training numbers were increased.

• Korean Journal of Psychosomatic Medicine
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• v.2 no.1
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• pp.59-68
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• 1994

A comparison was made regarding the degree of alexithymia among patients with psychosomatic disorders, anxiety disorders and depressive disorders. The author examined the degree of alexithymia in three groups : 100 psychosomatic patients(including 47 patients with tension headache), 52 outpatients with anxiety disorden, and 50 outpatients with depressive disorders. Alexithymia was assessed by Alexithymia provoked Response Questionnaires(APRQ) developed as a semi-structured interview form. No significant difference was found in the degree of alexithymia among Patients with Psychosomatic disorders, anxiety disorders, and depressive disorders. On the other hand, patients with tension headache were significantly more alexithymic than patients with anxiety disorders and depressive disorders, respectively. However, there was no significant difference in degree of alexithymia between patients with anxiety disorders and those with depressive disorders. Multiple regression analysis revealed that demographic variables such as set age, education level, and marital status did not make a significant influence on alexithymia scores. These results suggest a greater degree of alexithymia in patients with a specific group of psychosomiatic disorders such as tension headache than in patients with emotional disorders, unlike the previous report that in general, psychosomatic patients are alexithymic. Thus, it is necessary to develop special forms of interview which can induce and encourage expression of emotion as a therapeutic strategy for patients with tension headache.

• The Korean Journal of Physiology
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• v.2 no.2
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• pp.63-73
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• 1968

It is well known that mammalian alveolar membrane is covered with a very thin layer of surfactant film which characteristically reduces surface tension of alveolar membrane, and maintains alveolar stability. Since Clements in 1957 demonstrated that the surfactant is extractable by mincing the lung tissue in saline, various studies on the subject have been succeeded by many workers. However, the effect of radiation on the surfactant is not well clarified. Present study was attempted to observe the effect of x-irradiation on the activity of surfactant in rabbits. X-ray in dose of 300 r, 600 r or 900 r was irradiated to the chest of rabbits. The lung was removed from normal or irradiated rabbits sacrificed by arterial blood shedding, and lung-saline extract, adding 3 grams of lung tissue to 50 mili-liters of saline, was prepared by means of Vertis homogenizer. Tension-area diagram of lung extract was recorded automatically by a modified Langmuir-Wilhelmy balance with a synchronized recording system designed in this department. The surface tension of lung extract was measured at 1st, 2 nd, 3 rd, 7 th and 15 th post-radiation day in 300 r irradiated group, at 3 rd, 7 th and 15 th post-radiation day in 600 r irradiated group, 3 rd and 7 th post-radiation day in 900 r irradiated group respectively. For the histo-pathological study, lung tissue preparations were made in all irradiatiated groups on the day of experiment and in normal group. The results obtained are summarized as follows: 1. The minimal surface tension, maximal surface tension and stability index of normal rabbits lung extracts were 7.68 dynes/cm, 38.84 dynes/cm, and 1.39 respectively. 2. The activity of surfactant was depressed prominently by x-irradiation. However, increase in the dose of x-irradiation did not show any significant change in the degree of surfactant activity suppression. The most marked depression in surfactant was observed at the third post-radiation day in all irradiated groups. 3. Activity of surfactant depressed by x-irradiation showed a tendency of recovering to normal on 15 th post-radiation day. 4. The tendency of change in activity of surfactant following x-irradiation was somewhat correlative with histo-pathological changes. But the degree of depression of surfactant by x-irradiation did not correspond to the degree of histo-pathological changes, and recovery of lung tissue from radiation damage, tissue edema and congestion, seemed to be followed by restoration of surfactant activity. 5. The width of the tension-area diagram was measured at the surface area of 40% in lung extract of normal and x-irradiated rabbits. And it was found that the changes of the width corresponded well with that of minimum surface tension and of stability index in all normal and x-irradiated groups.