• 한국시뮬레이션학회논문지
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• 제10권1호
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• pp.63-65
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• 2001

To investigate the natural frequencies of curved piping systems with various elbow angles conveying flow fluid, a simulation is performed considering Initial tension due to the inside fluid. The system is analyzed by finite element method utilizing straight beam element. Elbow part is meshed using 4 elements, and the initial tension is considered by inserting equivalent terms into the stiffness matrix. Without considering the initial tension, the system becomes unstable, that is, the fundamental natural frequency approaches to zero value fast, as the flow velocity reaches critical value. With the initial tension terms, the system becomes stable where there is no abrupt decrease of the fundamental natural frequency. The change rate of the natural frequency with respect to the flow velocity reduces. As elbow angle increases, the system becomes stiffer, then around 150 degrees of the elbow angle the natural frequency has the largest value, the value decreases after the angle of the largest natural frequency. When angle is between 170 degrees and 179 degrees, the natural frequency is very sensitive. This means that small change of angle results in great change of natural frequency, which is expected to be utilized in the control of the natural frequency of the piping system conveying flow fluid.

• Journal of Oral Medicine and Pain
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• 제17권2호
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• pp.19-25
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• 1992

The pressure pain thresholds of head and neck muscles of patients suffering from tensiontype headache220, all female, ages ranged from 13 to 50 years (28.4$\pm$9.6) and 39 healthy controls, all female, ages ranged from 14 to 46 years (24.4$\pm$9.2) were recorded by the electronic algometer (Electyronic Algometer Type I, Somedic, Stockholm, Sweden). And the obtained results were as follows : 1. The pressure pain thresholds of patient group were lower than those of controls in superior sternocleidomastoid muscle, middle sternocleidomastoid muscle, and trapezius insertion muscle (P<0.001) 2. The pressure pain thresholds of patient group were not different from those of controls in anterior temporal, middle temporal, posterior temporal, deep masseter, anterior masseter, inferior masseter, medial pterygoid, posterior digastric, splenius capitus and upper trapezius muscle (P>0.05). 3. Seventy-one percent of tension-type headache patients had more than one muscle, of whicb pressure pain threshold was lowered significantly (less than mean of control - 1.5SD). 4. The pressure pain thresholds of head and neck muscles should be considered as a criterion for the diagnosis of tension-type headache.

• 대한기계학회논문집
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• 제14권3호
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• pp.646-655
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• 1990

본 연구에서는 EPIES 프로그램의 상세한 내용과 이를 이용한 5가지 파괴역학 시편에 대한 사례 연구에 대하여 보고하고자 한다.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.29-34
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• 2004

Numerical and experimental studies on pipeline laying for intake Deep Ocean Water are carried out. In the numerical study, an implicit finite difference algorithm is employed for three-dimensional pipe equations. Fluid non-linearity and bending stiffness are considered and solved by Newton-Raphson iteration. Seabed is modeled as elastic foundation with linear spring and damper. Top tension and general configuration of pipeline at a depth are predicted. It is found that control for tension to prevent being large curvature of pipeline is needed on th steep seabed and, it should be considered 23.5 ton of tension at a top of pipe on the process of pipeline laying at 400m of water depth The largest top tension of pipe on condition of the beam sea during pipe laying is shown from the experiment. The results of this study can be contributed to the design of pipeline laying for upwelling deep ocean water.

• 한국공간구조학회논문집
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• 제19권1호
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• pp.109-116
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• 2019

In this paper, the shape adjustment algorithm of the spoked wheel cable structures with retractable membrane system is studied. The initial tension of the membrane or cable is necessary to form the structure and its value is determined by the design shape. However, due to internal and external environmental influences, its shape may be different from the initial designed shape. In the case of the cable structures covered in this study, tension adjustment is necessary to maintain the designed shape because it influences the tension of the cable depending on the state of the retractable membrane. Therefore, we proposed an adjustment algorithm of an initial shape based on the force method. The effectiveness and validity of the methodology were examined through the applicable cable structures. The results of the shape adjustment analysis of the symmetric spoked wheel cable model were reliable and accurate results were obtained.

• 대한통합의학회지
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• 제10권4호
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• pp.23-34
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• 2022

Purpose : This study examined the effects of pain, neck dysfunction, psychosocial level, headache impact test (HIT), postural alignment, and trapezius muscle tone of the complex exercise program using dynamic taping in patients with tension headache and chronic neck pain with forward head posture. Methods : The design of this is a randomized controlled trial (RCT). Thirty-four patients with chronic neck pain were screened using a randomized assignment program and assigned to experimental group (n=17) and control group (n=17). Both groups underwent a complex exercise program. In addition, the experimental group dynamic taping was applied to the upper trapezius muscle. All interventions were applied three times per week for four weeks. The visual analogue scale (VAS), the neck disability index (NDI), short form-12 health survey questionnaire (SF-12), Headache impact test-6 (HIT-6), Craniovertebral angle (CVA), Cranial rotation angle (CRA), upper trapezius muscle tone were compared to evaluate the effect on intervention. Results : Both groups showed significant differences before and after the intervention in VAS, NDI, SF-12, HIT-6, and CVA, CRA (p<.05). In addition, significant differences in NDI and upper trapezius muscle tone were observed between the experimental group and control group (p<.05). Conclusion : A complex exercise program using dynamic taping for patients with tension headache and chronic neck pain with forward head posture are effective method with clinical significance in improving the function and reducing upper trapezius muscle tone.

• 대한통합의학회지
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• 제11권4호
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• pp.147-155
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• 2023

Purpose: Headache is a very common disease experienced at least once in daily life, and tension-type headaches have a high and increasing prevalence. Chronic headaches can cause functional damage and huge socioeconomic impacts. This study aimed to compare the effects of myofascial release technique with manual therapy and self-myofascial release technique using a foam roller on the pain threshold and body schema in patients with chronic tension-type headaches. Methods: The study was conducted on 20 patients living in Busan with chronic tension headaches. Myofascial release technique with manual therapy was performed on the suboccipital, sternocleidomastoid, scalene, and upper trapezius muscles. The self -myofascial release technique using a foam roller was applied to the cervical and thoracic muscles. A laterality test was performed using a recognized neck application developed to evaluate body schema ability. A pressure-pain threshold test was performed using an electronic pressure algometer to compare the results before and after the myofascial release technique. Results: After applying myofascial release with manual therapy and a foam roller, the pressure-pain threshold values showed significant changes in both groups (p<.05). As a result of the laterality test, myofascial release with manual therapy and a foam roller were applied to the painful area. The values showed significant changes in both groups (p<.05), but only the group using the foam roller showed a significant difference (p<.05) in painless areas. Conclusion: The myofascial release technique with manual therapy can be the primary treatment technique for pain control in painful areas. The self-muscle release technique using a foam roller can be an effective method when there is no pain or when maintenance is needed after pain control.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 봄 학술발표회 논문집
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• pp.97-104
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• 1999

This case study has been prepared to provide the practical data about construction of temporary shoring facilities (i.e. braced sheet pile excavation) and to utilize the case study information effectively for design and construction of future facilities. This case study includes information such as 1) installing measurement devices to monitor the deformation of the sheet pile walls and the subsoil in the vicinity after establishing the criteria for the sheet pile deflection; 2) monitoring the actual movement of the temporary facility after setting up the survey control standard (due to the movement of the temporary facility) : 3) inspecting the suitability of the temporary facility construction: and 4) analyzing and studying the result of the tension test after installing ground anchors.

• 연구논문집
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• 통권34호
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• pp.87-99
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• 2004

A spring tension control device is used as a very important part of an twister system. The friction force of tensioner must keep same friction force during winding in package. For satisfy this function, many device used common compression coil spring. In this paper, by using the case-building technique which was based on simple theory that unknown design variables are induced by given input design variables by the designer, design automation algorithm about rectangular section compression springs with elastic characteristic is developed. Four design equation are justified in using of analysis of torsion of straight bar of rectangular section and geometrical condition of coil spring. Four design equation and nine design variables are computed by case-building technique.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.290-295
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• 1992

Tendon driven method to drive one joint using two actuators is developed and implemented. While the method has advantages over conventional transmissions, it also has several drawbacks like tendon slack, elongation and endurability. In this paper, a compensation method of the intrinsic non-linearities of tendon is proposed to improve the performance of antagonistic tendon driven method. In this method, tendon tension measurement is prerequisite which is measured with strain gauge type tension sensor. The developed method is implemented on one link test bed with colocated and non-colocated position sensor.