• Journal of Industrial Convergence
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• v.1 no.1
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• pp.127-142
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• 2003

This Study examines the implications for event studies using the daily stock data. The output present the event study results. The event period is defined from 30 days before through 30 days after the event date, and is broken into four "windows" for abnormal return cumulation: the pre-event period, days -30 through -2; dajys -1 and 0, a period commonly investigated for the immediate impact of the event; and the post-event period, days +1 through +30. It shows how firm's information offerings affect the price process and consequent issues. The Patell Z test is an examples of a standardized abnormal return approach, which estimate a separate standard error for each security-event and assumes cross-sectional independence. The generalized sign test adjusts for the fraction of positive abnormal returns in the estimation period instead of assuming 0.5.

• Journal of Information Technology Applications and Management
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• v.27 no.6
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• pp.117-139
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• 2020

This research analyzes the factors that affect the consumers' participation of the internet-only banks, and suggests effective financial sales strategies and methods to attract more users. Through prior research review and interviews with experts, the factors affecting the consumers to sign up for the internet banks are identified. The actual user data from the internet banks are used for the analysis, providing more systematic and credible results. The research shows that social media buzz positively affects the user growth, proving Granger Causality relation of increasing social media buzz on K Bank increases K Bank users. The research also shows that marketing activities noticeably impacts K Bank's positive user growth. On the other hand, the event of Kakao Bank's grand opening shows negative effect. The results from the research validates the need for periodical monitoring process of social media buzz. Moreover, the research proves that the integrated analysis of social media buzz and marketing effect is also essential.

• Bulletin of the Korean Chemical Society
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• v.18 no.2
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• pp.161-164
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• 1997

Kinetic studies are carried out on the reactions of 1- and 2-naphthylmethyl arenesulfonates with anilines in acetonitrile at 25.0 ℃. The rates are faster for the 2-naphthylmethyl series than for the corresponding 1-naphthylmethyl series suggesting that there is a greater stabilization of positive charge development in the TS at the arylmethyl reaction center carbon for the former. The sign and magnitude of ρxz (=-0.12) are similar to those of the benzylic series. Thus, benzyl, 1- and 2-naphthylmethyl derivatives belong to a class of compounds which react with aniline nucleophiles through a relatively loose SN2 TS. Kinetic secondary deuterium isotope effects indicated that a stronger nucleophile and nucleofuge lead to a later TS as the definition of ρxz requires.

• Korean Journal of Materials Research
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• v.26 no.6
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• pp.293-297
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• 2016

Ni-C composite films were prepared by co-deposition using a combined technique of plasma CVD and ion beam sputtering deposition. Depending on the deposition conditions, Ni-C thin films manifested three kinds of microstructure: (1) nanocrystallites of non-equilibrium carbide of nickel, (2) amorphous Ni-C film, and (3) granular Ni-C film. The electrical resistivity was also found to vary from about $10^2{\mu}{\Omega}cm$ for the carbide films to about $10^4{\mu}{\Omega}cm$ for the amorphous Ni-C films. The Ni-C films deposited at ambient temperatures showed very low TCR values compared with that of metallic nickel film, and all the films showed ohmic characterization, even those in the amorphous state with very high resistivity. The TCR value decreased slightly with increasing of the flow rate of $CH_4$. For the films deposited at $200^{\circ}C$, TCR decreased with increasing $CH_4$ flow rate; especially, it changed sign from positive to negative at a $CH_4$ flow rate of 0.35 sccm. By increasing the $CH_4$ flow rate, the amorphous component in the film increased; thus, the portion of $Ni_3C$ grains separated from each other became larger, and the contribution to electrical conductivity due to thermally activated tunneling became dominant. This also accounts for the sign change of TCR when the filme was deposited at higher flow rate of $CH_4$. The microstructures of the Ni-C films deposited in these ways range from amorphous Ni-C alloy to granular structures with $Ni_3C$ nanocrystallites. These films are characterized by high resistivity and low TCR values; the electrical properties can be adjusted over a wide range by controlling the microstructures and compositions of the films.

• Korean Journal of Agricultural and Forest Meteorology
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• v.7 no.3
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• pp.185-191
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• 2005

An accurate prediction of dormancy release and bud burst in temperate zone fruit trees is indispensable for farmers to plan heating time under partially controlled environments as well as to reduce the risk of frost damage in open fields. A thermal time-based two-step phenological model that originated in Italy was applied to two important grapevine cultivars in Korea for predicting bud-burst dates. The model consists of two sequential periods: a rest period described by chilling requirement and a forcing period described by heating requirement. It requires daily maximum and minimum temperature as an input and calculates daily chill units (chill days in negative sign) until a pre-determined chilling requirement for rest release is met. After the projected rest release date, it adds daily heat units (anti-chill days in positive sign) to the chilling requirement. The date when the sum reaches zero isregarded as the bud-burst in the model. Controlled environment experiments using field sampled twigs of 'Campbell Early' and 'Kyoho' cultivars were carried out in the vineyard at the National Horticultural Research Institute (NHRI) in Suwon during 2004-2005 to derive the model parameters: threshold temperature for chilling and chilling requirement for breaking dormancy. The model adjusted with the selected parameters was applied to the 1994-2004 daily temperature data obtained from the automated weather station in the NHRI vineyard to estimate bud burst dates of two cultivars and the results were compared with the observed data. The model showed a consistently good performance in predicting the bud burst of 'Campbell Early' and 'Kyoho' cultivars with 2.6 and 2.5 days of root mean squared error, respectively.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.700-705
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• 2005

The purpose of this project is the derivation and development of techniques for the new estimation of robustness for the systems having uncertainties. The basic ideas to analyze the system which is the originally nonlinear is Lyapunov direct theorems. The nonlinear systems have various forms of terms inside the system equations and this investigation is confined in the form of bounded uncertainties. Bounded means the uncertainties are with same positive/negative range. The number of uncertainties will be the degree of freedoms in the calculation of the stability region. This is so called the robustness bounds. This proposition adopts the theoretical analysis of the Lyapunov direct methods, that is, the sign properties of the Lyapunov function derivative integrated along finite intervals of time, in place of the original method of the sign properties of the time derivative of the Lyapunov function itself. This is the new sufficient criteria to relax the stability condition and is used to generate techniques for the robust design of control systems with structured perturbations. Using this relaxing stability conditions, the selection of Lyapunov candidate function is of various forms. In this paper, the quadratic form is selected. this generated techniques has been demonstrated by recent research interest in the area of robust control design and confirms that estimation of robustness bounds will be improved upon those obtained by results of the original Lyapunov method. In this paper, the symbolic algebraic procedures are utilized and the calculating errors are reduced in the numerical procedures. The application of numerical procedures can prove the improvements in estimations of robustness for one-and more structured perturbations. The applicable systems is assumed to be linear with time-varying with nonlinear bounded perturbations. This new techniques will be extended to other nonlinear systems with various forms of uncertainties, especially in the nonlinear case of the unstructured perturbations and also with various control method.

• Journal of the Korean Data and Information Science Society
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• v.24 no.2
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• pp.257-265
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• 2013

As evaluating the health literacy is getting important, various measures for evaluation are being developed. Nevertheless, discussions about developing proper measures in Korean are still inactive. Therefore in this paper, we proposed Korean REALM (rapid estimate of adult literacy in medicine) measure that is composed of five point scale and investigated about its validity. As a result, we could find that Korean REALM measure which is composed of five point scale has high reliability, and that it formed one dimension as a result of factor analysis. Positive responses were lower than two point scale and correlation coefficient with NVS (the newest vital sign) appeared statistically significant. Therefore, we could conclude that Korean REALM measure that is composed of five point scale is a valid measurement. Furthermore, there were statistically significant differences between general students and department of nursing students about health literacy.

• The Research Journal of the Costume Culture
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• v.15 no.3 s.68
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• pp.431-445
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• 2007

The purpose of this study was to analyze and theorize the characteristics of femme fatale in fashion illustration since 1980. The method of this study was to analyze the documentaries for theoretical studies about femme fatale and the visual characteristics in fashion illustration works since 1980. The results of this study were as follows: Femme fatale expressed in the general realm of art was icon of fatal and seductive eroticism in late 19th century. She is composed of diverse images like mythology, exoticism, fear and sensuality. The characteristics of her image in fashion illustration were expressed into de-body image by union of animal and female body, or machine and female body, duplicity of death and sexuality, sexual decadence or abnormality and powerful masculine taste. First, de-body image by union of animal and female body, or machine and female body was expressed in transformed mythical image or bizarre and demonic image, grotesque image linked by picture of female body and painting of animal image, and cyborg image linked by machine and realistic female body by digital media. Second, duplicity of death and sexuality was expressed in juxtaposition by sexual pose, body and something metaphorical and symbolic depiction and de-constructive depiction of death. Third, sexual decadence or abnormality was expressed in fetishistic style, obscene depiction of cheap and hedonistic sexuality, masochistic depiction like antisocial and diseased sex appeal. Forth, powerful masculine taste was expressed in man's face, body, pose, masculine fashion, man's role related to crime and threatening weapon, etc. As mentioned above, femme fatale in fashion illustration was expressed in diverse images by fashion illustrator's point of view. Although she was originated by men's fantastic vision, she brings a catharsis to human being. And she is also recognized as new paradigm and positive cultural sign in our times.

• The Journal of Churna Manual Medicine for Spine and Nerves
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• v.7 no.1
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• pp.75-83
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• 2012

Objectives : The purpose of this study is to investigate the clinical application of acupuncture treatment to a cervical herniated intervertebral disc patient with hyperventilation syndrome developed after magnetic resonance imaging(MRI). Methods : A patient with cervical herniated intervertebral disc got hyperventilation syndrome after taking magnetic resonance imaging. To relieve symptoms, we took paperbag breathing first aid, but it had no effect. So we used acupuncture therapy with strong stimulation. To measure the outcome of the patient's improvement, we observed change of vital sign and verbal numerical rating scale(VNRS). Results : After 8 minutes of acupuncture treatment, the patient had significant improvement in change of vital sign and verbal numerical rating scale(VNRS). Conclusions : In emergency situation, acupuncture treatment as a first aid has a positive effect to control hyperventilation syndrome.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.1 no.2
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• pp.91-93
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• 2008

De Quervain's disease is a stenosing tenosynovitis that affects the synovial sheath of the tendons of the abductor pollicis longus and extensor pollicis brevis; it can be considered a work-related disease, since it frequently is associated with highly repetitive movements in jobs using the hands. The usual sign and symptom of de Quervain's diseases are positive Finkelstein's sign and pain and tenderness around the radial styloid process. The majority of de Quervain's disease has a good results to conservative treatment, but surgery can be performed in case of recurrence or pain last more than 6 months without improvement in spite of conservative treatment. We diagnosed a patient with atypical de Quervain's disease by ultrasonography, treated by local steroid injection and pain was relieved. We report a case of atypical de Quervain's disease evaluated by ultrasonography with brief of literatures.