• KCI Concrete Journal
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• v.11 no.3
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• pp.5-17
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• 1999

In recent years. the concept of the modified compression field theory (MCFT) was develped and applied to the analysis of reinforced concrete beams subjected to shear, moment, and axial load. Although too complex for regular use in the shear design or beams. the procedure has value in its ability to provide a rational method of anlysis and design for reinforced concrete members. The objective of this paper is to review the MCFT and apply it for the prediction of the response and shear strength of reinforced concrete beams A Parametric analysis was Performed on a reinforced T-section concrete beam to evaluate and compare the effects of concrete strength. longitudinal reinforcement ratio shear reinforcement ratio, and shear span to depth ratio in two different approaches the MCFT and the ACI code. The analytical study showed that the concrete contribution to shear strength by the MCFT was higher than the one by the ACI code in beams without stirrups, while it was lower with stirrups. On the other hand. shear reinforcement contribution predicted by the MCFT was much higher than the one by the ACI code. This is because the inclination angle of shear crack is much smaller than 45$^{\circ}$assumed in the ACI code.

• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.3
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• pp.723-736
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• 2014

Glass Fiber Reinforced Plastic (GFRP) structures are primarily manufactured using hand lay-up or vacuum infusion techniques, which are cost-effective for the construction of marine vessels. This paper aims to investigate the mechanical properties and failure mechanisms of the hybrid GFRP composites, formed by applying the hand lay-up processed exterior and the vacuum infusion processed interior layups, providing benefits for structural performance and ease of manufacturing. The hybrid GFRP composites contain one, two, and three vacuum infusion processed layer sets with consistent sets of hand lay-up processed layers. Mechanical properties assessed in this study include tensile, compressive and in-plane shear properties. Hybrid composites with three sets of vacuum infusion layers showed the highest tensile mechanical properties while those with two sets had the highest mechanical properties in compression. The batch homogeneity, for the GFRP fabrication processes, is evaluated using the experimentally obtained mechanical properties.

• Journal of Acupuncture Research
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• v.21 no.2
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• pp.301-314
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• 2004

Objectives : We studied to discover the patterns of DITI of the patients having a both neck and upper extremity pain on one side without any nerve root compression sign and the history of cervical disc herniation. Method : We selected 26 patients as an experimental group, who had visited for a both neck and upper extremity pain on one side without any nerve root compression sign, at the department of acupunture and moxibustion in Conmaul oriental medical hospital, during 2001. 01. - 2003. 09. And 31 normal adults were selected as a control group, not having any neck or arm pain and any history of cervical disease. We analyzed the segmental temperature statistically with t-test. Results & Conclusion : There was a significant change of temperatures in the scapula, posterior brachium, lateral forearm and dorsal hand area. And the experimental group showed cold spot and disruption of normal thermographic shape that were usually shown on the cervical sprain.

• Journal of Oriental Medical Thermology
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• v.4 no.1
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• pp.61-69
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• 2005

Objectives : We studied to discover the patterns of DITI of the patients having a both neck and upper extremity pain on one side without any nerve root compression sign and the history of cervical disc herniation. Method : We selected 26 patients as an experimental group, who had visited for a both neck and upper extremity pain on one side without any nerve root compression sign, at the department of acupunture and moxibustion in Conmaul oriental medical hospital, during 2001. 01. - 2003. 09. And 31 normal adults were selected as a control group, not having any neck or arm pain and any history of cervical disease. We analyzed the segmental temperature statistically with t-test. Results & Conclusion : There was a significant change of temperatures in the scapula, posterior brachium, lateral forearm and dorsal hand area. And the experimental group showed cold spot and disruption of normal thermographic shape that were usually shown on the cervical sprain.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1995.10a
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• pp.1-8
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• 1995

This work presents a new method to deal with buckling constraints. The mathematical optimization process of truss structures proposed earlier by the author has been proved to be the most rigorous method. The inclusion of buckling constraints, however, gives rise to a new problem The allowable compression stress of a member changes from one design iteration to another. This changing stress limit creates a good deal of noise in selecting active constraints and makes the solution process unstable. This problem can be overcome by introducing relaxation parameters. This work, however, aims at establishing a more rigorous method by containing the allowable compression stress in the left hand side of the associated constraint.

• Korean Journal of Remote Sensing
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• v.23 no.5
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• pp.431-437
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• 2007

Multi-Spectral Camera(MSC) on the KOMPSAT-2 satellite was developed and launched as a main payload to provide 1m of GSD(Ground Sampling Distance) for one(1) channel panchromatic imaging and 4m of GSD for four(4) channel multi-spectral imaging at 685km altitude covering l5km of swath width. Since the compression on MSC image chain was required to overcome the mismatch between input data rate and output date rate JPEG-like method was selected and analyzed to check the influence on the performance. In normal operation the MSC data is being acquired and transmitted with lossy compression ratio to cover whole image channel and full swath width in real-time. In the other hand the MSC performance have carefully been handled to avoid or minimize any degradation so that it was analyzed and restored in KGS(KOMPSAT Ground Station) during LEOP(Launch and Early Operation Phase). While KOMPSAT-2 had been developed, new compression method based upon wavelet for space application was introduced and available for next satellite. The study on improvement of image chain including new compression method is asked for next KOMPSAT which requires better GSD and larger swath width In this paper, satellite image chain which consists of on-board image chain and on-ground image chain including general MSC description is briefly described. The performance influences on the image chain between two on-board compression methods which are or will be used for KOMPSAT are analyzed. The differences on performance between two methods are compared and the better solution for the performance improvement of image chain on KOMPSAT is suggested.

• Earthquakes and Structures
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• v.20 no.4
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• pp.431-444
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• 2021

T-shaped column is usually used as side column in buildings, which is one of the weak members in structural system. This paper presented a quasi-static cyclic loading experiment of six specimens of reinforced concrete (RC) T-shaped columns under compression-flexure-shear-torsion combined loadings to investigate the effect in the ratio of torsion to moment (T/M) and axial compression ratio (n) and height-thickness ratio of flange plate (φ) on their seismic performance. Based on the test results, the failure characteristics, hysteretic curves, ductility, energy dissipation, stiffness degradation and strength degradation were analyzed. The results show that the failure characteristics of RC T-shaped columns mainly depend on the ratio of torsion to moment, which can be divided into bending failure, bending-torsion failure and shear-torsion failure. With the increase of T/M ratio, the torsion ductility coefficient increased, and in a suitable range, the torsion and horizontal displacement ductility coefficient of RC T-shaped columns could be effectively improved with the increase of axial compression ratio and the decrease of height-thickness ratio of flange plate. Besides, the energy dissipation capacity of the specimens mainly depended on the bending and shear energy dissipation capacity. On the other hand, the increase of axial compression ratio and the ratio of torsion to moment could accelerate the torsional and bending stiffness degradation of RC T-shaped columns. Moreover, the degradation coefficient of torsion strength was between 0.80 and 0.98, and that of bending strength was between 0.75 and 1.00.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.26 no.2
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• pp.73-80
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• 2020

Background: This study examined the effects of myofascial release exercise using an inflatable compression therapy ball on spinal flexibility in adults to present basic data to improve spinal flexibility. Methods: The participants were assigned randomly to two groups: the myofascial release exercise group (MRE, n=60) and the stretching exercise group (SE, n=60). The MRE group performed myofascial release exercise for the erector spine muscles using an inflatable compression therapy ball. The SE group performed stretching exercises of the erector spine muscles. Each exercise was performed in 3 sets of 10 repetition daily for one week. Results: The within-group comparison revealed a statistically significant difference between the pre-intervention and post-intervention measurements in only MRE group (p<.05). On the other hand, the between-group comparison revealed the MRE group to show statistically significant improvement in spinal flexibility (p<.05). In effect size, the MRE group was -1.82 (95% CI= -2.24~-1.39), and the SE group was -.7 (95% CI= -1.15~-.41). Conclusion: Myofascial release exercise for the erector spine muscles using an inflatable compression therapy ball was more effective in improving spinal flexibility than stretching exercises for the erector spinae muscles. However, although myofascial release exercise using inflatable compression therapy ball is more effective than stretching exercise, it is insignificant, and research is also insignificant. It is believed that more diverse studies using props will be needed in the future.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.9 no.2
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• pp.5-11
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• 2003

Thoracic outlet syndrome is actually a collection of syndromes brought about by abnormal compression of the neurovascular bundle by bony, ligamentous or muscular obstacles between the cervical spine and the lower border of the axilla. First of all a syndrome is defined as a group of signs and symptoms that collectively characterize or indicate a particular disease or abnormal condition. The neurovascular bundle which can suffer compression consists of the brachial plexus plus the C8 and T1 nerve roots and the subclavian artery and vein. The brachial plexus is the network of motor and sensory nerves which innervate the arm, the hand, and the region of the shoulder girdle. The vascular component of the bundle, the subclavian artery and vein transport blood to and from the arm. the hand. the shoulder girdle and the regions of the neck and head. The bony, ligamentous, and muscular obstacles all define the cervicoaxillary canal or the thoracic outlet and its course from the base of the neck to the axilla or arm pit. Look at the scheme of this region and it all becomes more easily understood. Compression occurs when the size and shape of the thoracic outlet is altered. The outlet can be altered by exercise, trauma, pregnancy, a congenital anomaly, an exostosis, postural weakness or changes. Thoracic outlet syndrome has been described as occurring in a diverse population. It is most often the result of poor or strenuous posture but can also result from trauma or constant muscle tension in the shoulder girdle. The first step to beginning any treatment begins with a trip to the doctor. Make a list of all of the symptoms which seem to be present even if the sensations are vague. Make a note of what activities and positions produce or alleviate the symptoms and the time of day when symptoms are worst. Also, note when the symptoms first appeared. This list is important and should also include any questions one may have.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.4
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• pp.577-585
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• 2010

The Military Tactical Communication technology for effective network-centric warfare is developing. Targeting broadband wireless transmission, core technology for connection, and Transmission technology that secure survivability under High-speed Movement environment. On the one hand, Tactical data communication system that reflects military characteristic is developing on the base of Legacy communication equipment which is used in the field. Because almost every military units in the field have used voice to communicate which lower efficiency of operation, they have made effort to Substitute voice communication which delays military Operation Tempo to digital communication. The Communications environment of troops in Forward edge of battle field area is very poor. Especially in terms of limited frequency allocation and bandwidth. Therefore, improving the efficiency of frequency is essential for Military Tactical Communication. This paper is about The Data Compression Method for increase of Efficiency in Tactical Data Communication over Legacy Radios which are UHF, VHF, HF Radio. I proposed and proved the most efficient Data Compression Method that reflects military characteristic, after analyzing the experimentation, which simulate CAS(Close Air Support mission) data transmission between Pilot and TACP.