• Physical Therapy Korea
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• v.12 no.2
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• pp.44-57
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• 2005

The objectives of this study were to examine the relative efficacy of three active exercise programs for work-related, chronic low back pain, and to observe to what extent the programs affected the mechanical stability of the lumbar region. The subjects were 64 employees who were randomly divided into three groups to match the three active exercise programs which were performed 3 times a week for 6 months. All subjects were assessed with the same measurements at a pre-study examination, and then were reassessed at 2 weeks, 3months and 6 months after the study. The pain intensity didn't show any significant difference among the three groups. However, the Oswestry Disability Index showed significant differences among the three groups at 6 months and the lumbar and thoracic exercise groups showed significant decreases compared to the general physiotherapy group (p<.05). Maximal stretching with both hands in the overhead direction showed a significant difference among the three groups at 3 months and 6 months, and the thoracic exercise group at 6 months showed a significant increase in overhead stretching compared to the lumbar exercise and general physiotherapy groups (p<.05). The group that performed maximal stretching with both hands in the overhead direction showed the most significant among the 3 months and 6 months. At 6 months, the thoracic exercise group showed a significant increase in overhead stretching compared to the lumbar exercise and general physiotherapy groups (p<.05). The lumbar region angle of inclination showed significant differences among the three groups at 2 weeks 3 months, and 6 months, with the thoracic exercise group being decreased more significantly at 6 months than the lumbar exercise and general physiotherapy groups (p<.05). Exercise aimed at increasing thoracic mobility has an effect on lumbar stability. Furthermore, it is far more effective for lumbar stabilization than general physiotherapy and deep muscle strengthening lumbar exercise.

• Fashion & Textile Research Journal
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• v.16 no.1
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• pp.145-152
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• 2014

The usage of textile-based sensors has increased due to their many advantages (compared to IT sensors) when applied to body assessment and comfort. Textile-based sensors have different detecting factors such as pressure, voltage, current and capacitance to investigate the characteristics. In this study, textile-based sensor fabrics with sheath-core type conductive yarns were produced and the relationship between capacitance changes and applied load was investigated. The physical and electric properties of textile-based sensor fabrics were also investigated under various laminating conditions. A textile based pressure sensor that uses a sheath-core conductive yarn to ensure the stability of the pressure sensor in the textile-based sensor (the physical structure of the reaction characteristic of the capacitance) is important for the stability of the initial value of the initial capacitance value outside the characteristic of the textile structural environment. In addition, a textile based sensor is displaced relative to the initial value of the capacitance change according to pressure changes in the capacitance value of the sensor due to the fineness of the high risk of noise generation. Changing the physical structure of the fabric through the sensor characteristic of the pressure sensor via the noise generating element of laminating (temperature, humidity, and static electricity) to cut off the voltage output element to improve the data reliability could be secured.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2003.05a
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• pp.17-20
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• 2003

In a recent paper (Hartwig, ms.) I have shown that it is possible to understand and discuss the changing Austausch (i.e., exchange of air parcels between different atmospheric layers) between the stratosphere and troposphere by means of long-term measurement on series of spallation products. It is well known (Friend 1961; Muet et al. 1966, Hartwig et al. 1969) that there is a seasonal pattern in the 7Be concentration of ground-level air with a maximum during May-June. This maximum is caused by enhanced exchange processes between the atmospheric compartments of the stratosphere and troposphere during this interval. Generally, those exchange processes are a consequence of stability and dynamics of the atmospheric compartments, which themselves result from, among other factors, the distribution of the heat sources in those compartments, namely the ground and the ozone layer. Because of the growing importance of anthropogenic infrared-active gases in the atmosphere, it is to be expected that the relative importance of those original, naturally occurring heat sources will be of lesser significance, thus altering the Austausch. And indeed, it has been shown (Hartwig, ms.) by considering the ratio of the annual maximum and minimum during a 28-yr period of 7Be ground-level concentration at Braunschweig, Germany (10$^{\circ}$33'E, 52$^{\circ}$17'N) (Kolb 1992; Wershofen 1993), that there is a steady decline in that ratio, thus indicating alteration of atmospheric Austausch within the last three decades.(omitted)

• International Journal of Aeronautical and Space Sciences
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• v.18 no.4
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• pp.623-640
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• 2017

The full nonlinear equations of an unmanned aerial vehicle ground taxiing mathematical dynamic model are built based on a type of unmanned aerial vehicle data in LMS Virtual.Lab Motion. The flexible landing gear model is considered to make the aircraft ground motion more accurate. The electric braking control system is established in MATLAB/Simulink and the experiment of it verifies that the electric braking model with the pressure sensor is fitted well with the actual braking mechanism and it ensures the braking response speediness. The direction rectification control law combining the differential brake and the rudder with 30% anti-skid brake is built to improve the directional stability. Two other rectifying control laws are demonstrated to compare with the designed control law to verify that the designed control is of high directional stability and high braking efficiency. The lateral displacement increases by 445.45% with poor rectification performance under the only rudder rectifying control relative to the designed control law. The braking distance rises by 36m and the braking frequency increases by 85.71% under the control law without anti-skid brake. Different landing conditions are simulated to verify the good robustness of the designed rectifying control.

• Knowledge Management Research
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• v.19 no.2
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• pp.109-132
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• 2018

Recently, new financial services related to FinTech has gained attention more and more. Online P2P financial services transactions such as FinTech require careful examination of the constituents of information systems as an investment is made based on the information presented on the online platform without direct face-to-face contact. The purpose of this study is to find out the success factors of online P2P Lending service among FinTech. To serve the purpose, we build IS (information system) success model, and then use Kano model and fuzzy analytic hierarchy process (Fuzzy-AHP) to find out factors for the success of online P2P Lending service. In particular, this study uses Kano model to classify information system satisfaction factors and to calculate the satisfaction coefficient. The Kano model, however, has a drawback of evaluating single criterion. Therefore, we use multi-criteria decision-making technique such as Fuzzy-AHP to derive the relative importance of the factors. The analysis results show different results depending on the analysis technique. In the Kano model, most of the information system factors are a one-dimensional quality attribute. The satisfaction coefficient is highest for personalized service, followed by the responsiveness of service, ease of using a system, understanding of information, usefulness of information' reliability. The service reliability is the highest in dissatisfaction coefficient, followed by system security, service responsiveness, system stability, and personalized service. The results of the Fuzzy-AHP analysis shows that the usefulness of information quality, the personalization of service quality, and the security of system quality are the significant factors and the stability of system quality was a secondary factor.

• Journal of Korean Society for Atmospheric Environment
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• v.34 no.2
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• pp.331-341
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• 2018

Hazardous air pollutants(HAPs) in the atmosphere are regulated as major air pollutants in Korea by the Air Pollution Control Act. In order to manage and control HAPs, accurate standards, which are traceable to the International System of Units(SI), are required. In this study, primary standard gas mixtures(PSMs) of volatile organic compounds(VOCs) which are specified as HAPs were developed at $1{\mu}mol/mol$ levels. The selected fourteen VOCs include Benzene, Toluene, Ethylbenzene, m-Xylene, Styrene, o-Xylene, Chloroform, 1,1,2-Trichloroethane, Trichloroethylene, Tetrachloroethylene, 1,1-Dichloroethane, Carbon tetrachloride, 1,3-Butadiene, and Dichloromethane. The HAPs PSMs were gravimetrically prepared in aluminum cylinders and their consistency was verified within the relative expanded uncertainty of 0.71% (k=2). Potential adsorption loss onto the internal surface of cylinders was estimated by cylinder-to-cylinder division method. No adsorption loss was observed within the uncerainty of 0.53%. The long-term stability of the HAPs PSMs was evaluated comparing with freshly prepared HAPs PSMs. The HAPs PSMs were stable for one year within the uncertainty of 0.38%. The final uncertainty of the PSMs was determined by combining the preparation uncertainty, verification uncertainty, and stability uncertainty. Finally, traceable and stable HAPs PSMs at $1{\mu}mol/mol$ levels were developed with the uncertainty of less than 0.76% in high-pressure aluminum cylinders.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.05
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• pp.245-248
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• 1997

Excessive stress on the bone-stem interface may cause local micromotion that could produce midthigh pain, interface bone resorption and prevent bony ingrowth. It is important for clinician and prosthetic designer to develop an understanding of the load transfer mechanism, its associated stress pattern and its relationships with the particular mechanical characteristics of the femoral stem designs. Finite element method (FEM) is preeminently suited to provide information in this respect. The authors developed 3-dimensional numerical finite element models implanted with the straight stem which is composed of total 1170 elements of 8 nodes and with the curved stem which is composed of total 885 elements of 8 node, and analysed the relative micromotions between the straight stem and the curved stem in immediate postoperative stage of an uncemented total hip replacement in load simulating the single leg stance. The results showed that the rotational displacement was occupied over 90% of total micromotion in both types of stem and was peak at the proximal medial portion of the stem, but markedly less distally. The curved stem was more stable especially in terms of rotational stability. It is recommended that surgeons do not allow the patient weight bearing until bony ingrowth was achieved. In the future more attention should be drawn to increase initial rotational stability of the two types of femoral stem to prevent loosening from excessive micromotion.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.8 s.350
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• pp.6-12
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• 2006

Recently, according to the rapid development of mobile system, the development of relative mobile components has been required, and especially, with the miniaturization of mobile component, the complex with nearby components has been progressed. In this paper, multi-output VC-TCXO (Voltage Controlled-Temperature Compensated Crystal Oscillator) for WCDMA integrates the additional CMOS inverter, so it can be the normal clipped sinewave output and additional CMOS output, and also it can be satisfied the VC-TCXO's requirements for WCDMA system. And the important characteristics of reference oscillator, like phase noise and frequency short term stability, are satisfied with WCDMA(UMTS) system's requirement In this paper, however, 25MHz is used for reference frequency, similarly and practically, we think that it can be used from 10MHz to 40MHz.

• Journal of the Korean Geotechnical Society
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• v.28 no.5
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• pp.5-12
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• 2012

Geotextile tube method is the latest application process to construct a variety of civil structures such as river and coastal structures by using geotextile which is a high polymer synthetic fiber. In this paper, laboratory tests and field tests were conducted in order to identify the behavior, stability and application possibility of geotextile tube which prevents the erosion of coastal sand. As a result of large-scale direct shear test, which is one of laboratory tests, the increase in friction angle was shown as the relative density increased, and friction angle of sand/geotextile was larger than that of sand/sand. As a result of field test, the behavior and stability during construction and after construction were identified through measurement, and the effect of preventing erosion was confirmed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.2 no.1
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• pp.41-47
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• 1973

In the present work, the quality stability of sun-dried Alaska pollack, Theragra chalcogramma, was discussed in the aspects of non-enzymatic discoloration as a function of relative humidity during storage at room temperature$(20^{\circ}C)$. Frozen Alaska pollack was dressed, filleted, dried for 48 hours in the open air, and finally stored in cylindrical acrylic chambers which contained saturated specific salt solutions proposed by Rockland(1960) for humidity control. The color development of the product was analyzed by spectrophotometry at 10 day-intervals during the storage. Lipid oxidation was measured as TBA value at wavelength of 538nm. And browning pigments were extracted, divided into two fractions and measured at 460nm: one was chloroform-methanol (2:1 v/v)soluble fraction attributed to lipid oxidation, and the other was water dialyzed fraction caused by so called Maillard reaction. The TBA value showed a maximum on 30 day storage, hereafter, intended to decrease gradually. On the other hand, the rate of brown pigment development in water dialyzed fractions as well as in chloroform-methanol soluble fractions was lower at 34 to 45%RH than at any other case, and propagation of lipid oxidation was also diminished at the same levels of humidity. From the facts described previously, it is recognized that storage at 34 to 45%RH provides higher quality stability for sun-dried Alaska pollack.