• Magazine of the Korean Society of Agricultural Engineers
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• v.30 no.4
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• pp.134-153
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• 1988

This paper was carried out to investigate the existence of a unique stress- strain behavior by obtaining some factors influencing the time dependent stress- strain behavior of clay. The results obtained from this study were summarized as follows ; 1. The relationship between stress ratro and strain in normally consolidated clay was in- dependent on pre-shear consolidation pressure. Therefore, shear strain could be expressed as a function with stress ratio. 2. The constitutive equation of shear strain on Modified Carn Clay Model coincided better with the observed value than Cam Clay Model. 3. The relationships between deviator stress and shear strain, between pore water pressure and shear strain were unified by the mean equivalent pressure. 4. The shear strain contour in norrnally consolidated clay was increased linearly through origin, but that in overconsolidated clay was not in accordance with the result of the former. 5. Because the effective stress path of normally consolidated clay was unified by the mean equivalent pressure, state boundary surface in (e,p,q) space was transformed into two dimensional surface. But it was considered to be suitable that the unified stress- strain in overconsolidated clay be expressed by a function with overconsolidation ratio. 6. The deviator for constant strain was increased linearly with increment of strain rate ($\varepsilon$) on semi-log scale, but pore water pressure was decreased. 7. The behavior of stress relaxation was transformed from linear to curvilinear with inc - rement of strain rate before stress relaxation test, and pore water pressure was increased in total range. 8. The strain of creep was increased linearly with increment of time on semi-log scale. The greater the strain rate before creep test became, the greater the increment of strain of creep became. And the pore water pressure during creep test was increased generally with increment of time on semi-log scale.

• Safety and Health at Work
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• v.4 no.3
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• pp.166-176
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• 2013

Background: Effective policy implementation is essential for a healthy workplace. The Ryan-Kossek 2008 model for work-life policy adoption suggests that supervisors as gatekeepers between employer and employee need to know how to support and communicate benefit regulations. This article describes a workplace intervention on a national employee benefit, Family and Medical Leave Act (FMLA), and evaluates the effectiveness of the intervention on supervisor knowledge, awareness, and experience with FMLA. Methods: The intervention consisted of computer-based training (CBT) and a survey measuring awareness and experience with FMLA. The training was administered to 793 county government supervisors in the state of Oregon, USA. Results: More than 35% of supervisors reported no previous training on FMLA and the training pre-test revealed a lack of knowledge regarding benefit coverage and employer responsibilities. The CBT achieved: (1) a significant learning effect and large effect size of d = 2.0, (2) a positive reaction to the training and its design, and (3) evidence of increased knowledge and awareness regarding FMLA. Conclusion: CBT is an effective strategy to increase supervisors' knowledge and awareness to support policy implementation. The lack of supervisor training and knowledge of an important but complex employee benefit exposes a serious impediment to effective policy implementation and may lead to negative outcomes for the organization and the employee, supporting the Ryan-Kossek model. The results further demonstrate that long-time employees need supplementary training on complex workplace policies such as FMLA.

• Animal cells and systems
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• v.8 no.4
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• pp.307-312
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• 2004

Fast kinetics of transient pH changes and difference spectrum formation have been investigated following mixing of ADP/ATP with partially purified plasma membrane PM-ATPase of the pathogenic yeast Candida albicans in the presence of five nutrients: glucose, glutamic acid, proline, lysine, and arginine and two analogs of glucose: 2-deoxy D-glucose and xylose. Average $H^+$- absorption to release ratio, indicative of population of ATPase undergoing complete hydrolytic cycle, was found to be 0.27 for control. This ratio varied between 0.25 (proline) to 0.36 (arginine) for all other compounds tested, except for glucose. In the presence of glucose, $H^+$- absorption to release ratio was exceptionally high (0.92). While no UV difference spectrum was observed with ADP, mixing of ATP with ATPase led to a large conformational change. Exposure to different nutrients restricted the magnitude of the conformational change; the analogs of glucose were found to be ineffective. This suppression was maximal in the case of glucose (80%); with other nutrients, the magnitude of suppression ranged from 40-50%. Rate of $H^+$- absorption, which is indicative of E~P complex dissociation, showed positive correlation with suppression of conformational change only in the case of glucose and no other nutrient/analog. Mode of interaction of glucose with plasma membrane $H^+$-ATPase thus appears to be strikingly distinct compared to that of other nutrients/analogs tested. The results obtained lead us to propose a model for explaining glucose stimulation of plasma membrane $H^+$-ATPase activity.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.8
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• pp.297-308
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• 2020

This study exemines the roles of corporate social activity (CSR) and executive compensation structure on the pricing of seasoned equity offerings (SEOs) with special focus on the role of CSR in reducing the level of information asymmetry between managers and future shareholders of issuing firms through SEOs. This study also investigates the interaction between executive compensation structure and CSR on the discounting of SEOs. We use a sample of 2,102 seasoned equity offerings of U.S. firms with CSR scores from 1995 to 2015 in our OLS fixed effect regression analysis. The results show that issuing firms with high CSR are more likely to expericence a lower degree of the SEO discount. The results also document a positive association between CSR and a high proportion of equity-based compensation of issuing firms' executives. The findings of this paper confirm that CSR attenuates the impact of information asymmetry and the pre-SEO price uncertainty on the pricing of the offers and hence the SEO discount. Furthermore, CSR reinforces the impact of executive firm-related wealth on the discounting of seasoned equity offerings. It appears that firm-related wealth motivates managers to actively engage in reducing information asymmetry activities before SEOs, thereby decreasing the SEO discount.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.46 no.6
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• pp.132-145
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• 2009

We present the framework for JND based Illumination and Color Restoration Using Edge-preserving filter for restoring distorted images taken under the arbitrary lighting conditions. The proposed method is effective for appropriate illumination compensation, vivid color restoration, artifacts suppression, automatic parameter estimation, and low computation cost for HW implementation. We show the efficiency of the mean shift filter and sigma filter for illumination compensation with small spread parameter while considering the processing time and removing the artifacts such as HALO and noise amplification. The suggested CRF (color restoration filter) can restore the natural color and correct color distortion artifact more perceptually compared with current solutions. For the automatic processing, the image statistics analysis finds suitable parameter using JND and all constants are pre-defined. We also introduce the ROI-based parameter estimation dealing with small shadow area against spacious well-exposed background in an image for the touch-screen camera. The object evaluation is performed by CMC, CIEde2000, PSNR, SSIM, and 3D CIELAB gamut with state-of-the-art research and existing commercial solutions.

• Annals of Clinical Neurophysiology
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• v.5 no.1
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• pp.16-20
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• 2003

Background: Mobile phone has become a very popular device used in everyday our lives. However, the possible hazard to human body such as brain tumor has been proposed intermittently. This unwanted possibility was calmed down due to the absence of definite evidence of hazard. This study was performed to see the effect of mobile phone use on the brain temperature. Methods: In 20 volunteers, we performed 4 steps of temperature measuring procedure. Four steps are pre-use (S1, basal state), wire-phone (S2, conventional telephone), PCS phone (S3, using 1,750~1,900 MHz), cellular phone (S4, using 820 MHz) states. Brain temperatures were measured by radiothermometer at 10 sites (5 sites in each hemisphere) of the brain after 5minutes of telecommunication through the phones. The final data were compared using paired t-test. Results: In PCS phone user group (Average; $35.73708^{\circ}C$), brain temperature decreased (with statistical significance, p<0.05), compared to those of non-user group (Average; $35.9527^{\circ}C$) or conventional wire phone user group. In cellular phone user group (Average; $35.82155^{\circ}C$), brain temperature decreased slightly (without statistical significance, p>0.05) compared to those of non-user group (Average; $35.9527^{\circ}C$) or conventional wire phone user group (Average; $35.922^{\circ}C$). The temperature change was not limited to the mobile phone applied side but on both hemisphere of the brain. Conclusion: In conclusion, mobile phone (especially PCS phone) decreased brain temperature in both hemispheres without side-to-side temperature difference. In addition, this study suggests possibility of radiothermometer application to the study of electromagnetic wave effect and protection method research in the future.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.23 no.11
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• pp.1239-1247
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• 2012

In this paper, design and fabrication of solid state power amplifier(SSPA) using GaN HEMT chip for X-band frequency are presented. The SSPA consists of the power supply for stable power and the control unit for communication and controlling the internal module, the RF Part to amplify RF signal, In particular the adopted active device for the RF Parts is GaN HEMT Bare chip of TriQuint company, the RF parts consists of pre-stage, drive-stage, main power-stage and each amplifier is designed with input and out matching circuit. The developed power amplifier demonstrated more than 300 W peak output power in condition of 26 % duty, max. pulse width 100us for the X-band frequency( 500 MHz bandwidth) and can apply to marine radar systems.

• Tuberculosis and Respiratory Diseases
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• v.72 no.1
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• pp.37-43
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• 2012

Background: A lung bulla may rarely shrink as a result of an inflammation within the bulla or a closing of a bronchus involved in the inflammation process, which is termed 'autobullectomy'. The purpose of this study was to describe clinical features of patients with regressions of bullae during follow-up. Methods: We retrospectively reviewed the cases and individuals who showed unequivocal evidence of interval regressions in a pre-existing bulla. A total of 477 cases with a bulla >5 cm in diameter were screened manually. Thirty cases with bullae that showed regression during follow-up were selected. Results: Regressions of large bullae occurred in 30 of 477 cases (6.3%). The median age of those patients was 61 (range, 53~66) years and 87% of those patients were men. The main cause of a bulla was emphysema (80%). Among 30 cases, 16 cases had pneumonia in the lung parenchyma of the peribullous area. Another 7 cases had a regressed bulla accompanied by an air-fluid level within the bulla. The remaining 7 cases showed a spontaneous regression of the bulla without such events. Complete regression of a bulla occurred in 25 cases. A follow-up chest-X ray showed that in all cases except one, the bulla remained in a collapsed state after 24 months. Forced expiratory volume in one second ($FEV_1$) improved in 3 cases and the other 2 cases had increased forced vital capacity (FVC). In addition, total lung capacity (TLC) and residual volume (RV) decreased in another 2 cases. Conclusion: Regression of a lung bulla occurred not only after pneumonia or the presence of air-fluid level within the bulla, but also without such episodes. The clinical course of regression of a lung bulla varied. After regression of a bulla, lung function could be improved in some cases.

• Korean Journal of Health Education and Promotion
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• v.26 no.2
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• pp.15-23
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• 2009

Objectives: This study was conducted to investigate the relationship between physical activity function and stages of self-change for exercise in the aged of a farming village. The object of this research was to make with the basic data for the exercise program for the aged of rural area. Methods: This study was a volunteer sample of 612 persons, 60 years and above, who were living at the 2 farming villages, in 2005 July. This instruments were analyzed using frequency analysis and descriptive statistics, multiple regression analysis. Results: The distribution of stages of self-change of the research object person showed that the pre-contemplation stage was most with 57.2%, and the contemplation stage : 8.1%, the preparation stage : 2.2%, the action stage : 22.5%, the maintenance stage : 10.0%. The person who having good physical function state and advanced stages of self-change of exercise were higher in the ratio of the educational level and the income level. Factors for physical function were effected by the aging and the woman negatively. Conclusion: Physical function scores were highly correlated with stages of self-change for exercise. So it will be helpful that the program which designed by one's physical function and stage of self-change for exercise would applied the one.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.8B
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• pp.797-804
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• 2009

Recently, SIP(Session Initiation Protocol) is used to set up and manage sessions for multimedia applications such as VoIP(Voice over IP) and IMS(IP Multimedia Subsystem). However, because SIP operates over the Internet, it is exposed to pre-existed internet security threats such as service degradation or service disruptions. Multimedia applications which are delay sensitive even suffers more from the threats mentioned above. The proposed methods so far to detect SIP INVITE flooding are CUSUM(Cumulative Sum), Hellinger distance and adaptive threshold, but among methods only take normal state into consideration. So, it is not capable of adapting the condition of the network congestion which are dynamically changing. In this paper, SIP INVITE flooding detection algorithm considering network congestion which enables efficient detections of such attacks is proposed. The proposed algorithm is expected to detect other types of attacks such as BYE and CANCEL more precisely compared to other methods.