• Journal of applied mathematics & informatics
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• v.31 no.5_6
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• pp.711-732
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• 2013

In this paper, we are interested in finding explicit numerical formulas to evaluate defaultable bonds prices of firms. For this purpose, we use a default intensity whose values depend on the credit rating of these firms. Each credit rating corresponds to a state of the default intensity. Then, this regime switches as soon as one of the credit rating of a firm also changes. Moreover, this regime switching default intensity model allows us to capture well some market features or economics behaviors. Thus, we obtain two explicit different formulas to evaluate the conditional Laplace transform of a regime switching Cox Ingersoll Ross model. One using the property of semi-affine of the model and the other one using analytic approximation. We conclude by giving some numerical illustrations of these formulas and real data estimation results.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.6
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• pp.8-13
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• 2015

Recently, Illumination industry of LED module has been focused to industry technology for energy conservation of nation. The LED device is excellent to power efficiency due to semiconductor light source element. And the application to the lighting circuit technology can be designed to the sensitive lighting system for human sensitivity control. In this paper, as a process for analyzing the operating temperature of standardized electronic device including LED device has analyzed about fusing character with in designed micro fuse for electronic device protection from the over current. Using the de-rating technique, which is performed to micro fuse fusing test in the range of $-30^{\circ}C{\sim}120^{\circ}C$ thermostatic chamber. To the output data in each temperature zone, it is performed to first-order linear fitting. Additionally, applying the resistance temperature coefficient and statistical data for the reliable analysis has derived to the metal element resistance of micro fuse with temperature change of the thermostatic chamber. As a research result, The changed temperature effect of thermostatic chamber was confirmed regarding fusing time change.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.1
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• pp.1-7
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• 2015

The environmental regulations for CO2 emissions from the ship have been established recently, and fuel oil price has been increased continuously. In order to overcome these circumstances, Energy Saving Devices (ESDs) have been developed continuously to reduce the fuel oil consumption and improve the propulsive efficiency. This paper describes the trial performance of PBCF (Propeller Boss Cap Fins), SCHNEEKLUTH duct, Asymmetric rudder bulb and Mewis duct applied to handy-size bulk carriers. As a result, SCHNEEKLUTH duct is more effective than other energy saving devices at the reducing the fuel oil consumption and the improvement of the propulsive efficiency. In addition, it is confirmed that SCHNEEKLUTH duct is really effective in the vibration of the deck house. And the fuel oil consumption can also be reduced through main engine de-rating.

• Steel and Composite Structures
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• v.26 no.6
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• pp.705-717
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• 2018

This paper presents a numerical investigation on the mechanical performance of concrete-filled dual steel tubular columns of circular section subjected to concentric axial load. A three-dimensional numerical model is developed and validated against a series of experimental tests. A good agreement is obtained between the experimental and numerical results, both in the peak load value and in the ascending and descending branches of the load-displacement curves. By means of the numerical model, a parametric study is carried out to investigate the influence of the main parameters that determine the axial capacity of double-tube columns, such as the member slenderness, inner and outer steel tube thicknesses and the concrete grade - of both the outer concrete ring and inner core -, including ultra-high strength concrete. A total number of 163 numerical simulations are carried out, by combining the different parameters. Specific indexes are defined (Strength Index, Concrete-Steel Contribution Ratio, Inner Concrete Contribution Ratio) to help rating the relative mechanical performance of dual steel tubular columns as compared to conventional concrete-filled steel tubular columns, and practical design recommendations are subsequently given.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.2
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• pp.91-100
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• 1998

This paper is to study on rating system of some shrubs for pedestrian control with concentrate upon the density of branch. It was usd that Hibiscus syricacus L., Spiraea prunifolia var. simpliciflora Nak, Ligustrum obtusifolium S. et Z., Callicarpa dichotoma Raeusch., Rhoododendron mucrionulatum Turcz., Syringa vulgaris L., Weigela subsessilis L. H. Bailey, Cercis chinensis bunge, Forsythia koreana Nak., Euonymus alatus Sieb, Chaenomeles speciosa Nak., orbaria sorbifolia var. stellipila Max., Deutzia parviflora Bunge, Kerria japonica De Candolle, Prunus tomentosa Thunberg ex Murray, Purunus grandulosa for. albiplena Koehne. Shrubs are invesitgated ito the density of branch, the power of sprout, height, a rate of growth, hardness of naturalizaton, crown width and existence of thorns. Shrubs belonged to high group of rating system for pedestrian control were Euonymus alatus Sieb, Purunus grandulosa for. albiplena Koehne, Chaenomeles speciosa Nak., Spiraea prunifolia var. simpliciflora Nak., Prunus tomentosa Thunberg ex Murray, Rhododendron mucronulatum Turcz., Hibiscus syricacus L., Ligustrum obtusifolium S. et Z., Syringa vulgaris L., Weigela subsessilis L.H.Bailey.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1488-1489
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• 2007

This paper described the current rating methodology of high voltage connectors used for high efficient vehicles. Typically, temperature rise at rated current has been used to rate power contacts in automotive connector. However, for automotive applications, they are required to meet severe environmental conditions and high connector reliability. Therefore, it is very important to rate correctly an allowable current of automotive connector. We have measured the contact characteristics through current cycling at room temperature and at high temperature, as well as temperature rising and current carrying capacity by de-rating. From the above results, we have developed high reliable contacts with about 80 Amperes.

• Journal of Information Processing Systems
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• v.9 no.3
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• pp.435-460
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• 2013

Recommender systems are popular applications that help users to identify items that they could be interested in. A recent research area on recommender systems focuses on detecting several kinds of inconsistencies associated with the user preferences. However, the majority of previous works in this direction just process anomalies that are intentionally introduced by users. In contrast, this paper is centered on finding the way to remove non-malicious anomalies, specifically in collaborative filtering systems. A review of the state-of-the-art in this field shows that no previous work has been carried out for recommendation systems and general data mining scenarios, to exactly perform this preprocessing task. More specifically, in this paper we propose a method that is based on the extraction of knowledge from the dataset in the form of rating regularities (similar to frequent patterns), and their use in order to remove anomalous preferences provided by users. Experiments show that the application of the procedure as a preprocessing step improves the performance of a data-mining task associated with the recommendation and also effectively detects the anomalous preferences.

• Journal of Korean Medicine Rehabilitation
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• v.31 no.4
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• pp.211-219
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• 2021

This study reports the effectiveness of Korean medicine and Chuna manual therapy on patients with De Quervain's tenosynovitis. Two patients were treated with Chuna manual therapy, electro-acupuncture, moxibustion therapy. We used numeric rating scale (NRS), Finkelstein's test, sonography to measure changes during treatment. After each treatment, NRS, Finkelstein's test, sonography outcome were improved. Korean medicine including Chuna manual therapy can be effectively used to improve De Quervain's tenosynovitis. This study may suggest that korean medicine including Chuna manual therapy can be effective for De Quervain's tenosynovitis.

• Journal of the Korean Society for Precision Engineering
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• v.33 no.1
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• pp.53-61
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• 2016

Angular misalignment has a significant effect on the characteristics of angular contact ball bearings (ACBBs). This paper presents an analysis of fatigue life for ACBBs subjected to angular misalignment. A simulation model is developed with de Mul's bearing model and the ISO basic reference rating life model. Simulation is performed to calculate the life of the ACBBs subjected to angular misalignment. The numerical results show that angular misalignment influences the load distribution significantly, thus reducing the bearing rating life. The fatigue life of ACBBs is decreased by angular misalignment regardless of axial preload, external radial load and rotational speed. The results show that angular misalignment should be maintained at less than 1mrad for ACBBs.

• Korean Journal of Acupuncture
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• v.33 no.1
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• pp.33-36
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• 2016

Objectives : The objective of this clinical case report is to describe an acupuncture treatment for dizziness after acoustic neuroma surgery. Methods : The patient was treated with acupuncture treatment for 4 months, 3 times per week. Duration for every treatment were 30 min by manual acupuncture with De Qi, which was designed to treat the dizziness and accompanied symptoms. Side-lying test was also used to evaluate dizziness and Hamilton Rating Scale for Depression(HDRS) to evaluate depression. We evaluated the clinical result of the treatment by observing the patients symptoms. Results : After acupuncture treatments for 4 months, patient's Side-lying test reduced to 10 second, and Hamilton Rating Scale for Depression reduced 4 points. Conclusions : The clinical case treatment report may suggest that the acupuncture treatment can be a meaningful option for the intractable dizziness after acoustic neuroma surgery, and also able to reduced depression scale.