• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.2
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• pp.263-268
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• 2003

In this paper, we have investigated double gate (DG) MOSFET structure, which has main gate (NG) and two side gates (SG). We know that optimum side gate voltage for each side gate length is about 3V in the main gate 50nm. Also, we know that optimum side gate length for each for main gate length is about 70nm. DG MOSFET shows a small threshold voltage roll-off. From the I-V characteristics, we obtained IDsat=550$mutextrm{A}$/${\mu}{\textrm}{m}$ at VMG=VDS=1.5V and VSG=3.0V for DG MOSFET with the main gate length of 50nm and the side gate length of 70nm. The subthreshold slope is 86.2㎷/decade, transconductance is 114$mutextrm{A}$/${\mu}{\textrm}{m}$ and DIBL (Drain Induced Barrier Lowering) is 43.37㎷. Then, we have investigated the advantage of this structure for the application to multi-input NAND gate logic. Then, we have obtained very high cut-off frequency of 41.4GHz in the DG MOSFET.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.4 s.121
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• pp.342-349
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• 2007

Following the 2002 World-Cup held in Korea, studies have been actively conducted on plans to utilize all-weather stadiums of fine figures, where large-scale spaces are available for various utilizations. In Japan, dome-type stadiums have been built and are utilizing across the whole nation not only for sports events but also variety of other large-scale events. PTFE(poly tetra fluoro ethylene) is one of the membrane material mainly used for the outer ceiling surface of membrane structures. However, there has not been enough research on the acoustical properties of PTFE membrane material which has been widely used in the multi-purpose stadiums. In this study, air permeability values and sound absorption coefficient of PTFE membrane materials were measured and evaluated in the gymnasium. From the results of measurements of sound absorption coefficient and air permeability of inner membrane materials, it was found that the sound absorption coefficient was good in the air permeability range of $5{\sim}15\;cc/cm^2/s$. Also the relation ship between air permeability and sound absorption coefficient was very high and the sound absorption coefficient was the highest in the range of $6{\sim}9\;cc/cm^2/s$. Secondly, an analysis on the measurements sound absorption characteristics of inner membrane material reveals that the overall sound absorption coefficient was stabilized(higher than 0.5 throughout the whole frequency bands) when the air space behind the membrane material was deeper than 600 mm. When PTFE sound absorptive membrane material was installed in the ceiling of gymnasium, it was confirmed that sound absorptive membrane material can reduce reverberation and increase speech intelligibility in the gymnasium.

• Proceedings of the Korea Contents Association Conference
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• 2006.05a
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• pp.298-301
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• 2006

This study was conducted to observe the changes in trend of a beautiful face defined in different time frames. Affective space model was used in this study, for physical components of a face are far too complicated and undistinguishable from simple categorization of a face by facial characteristics. It is because using a facial model defined only by its physical characteristics renders a complicated and multi-dimensional space, whereas an emotional facial model enables a 2-dimensional space for easier observation and explanation. Scope of the study is focused on faces of the Korean female celebrities, looking at the media frequency, popularity rankings in well-known portal sites, and popularity ratings by reliable search organizations as of 2006. Celebrities in their 20s and early 30s were selected. In addition, to observe any trend in a beautiful face with the passage of time, the study looked at changes or trends in the last 5 years by comparing the faces of celebrities in year 2006 with their faces stored in the database since five years ago.

• Journal of Korean Academy of Nursing
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• v.41 no.6
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• pp.780-787
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• 2011

Purpose: This study was conducted to examine activities of daily living (ADL) of older adults admitted to Korean long-term care hospitals (LTCHs), and to explore the patient and organizational factors that have an impact on the ADL of this population. Methods: A secondary analysis of the Korean minimum data set (K-MDS) of patients (N=14,369) and of the profiles of LTCHs (N=358) from the Health Insurance Review and Assessment Service was done between January and July 2008. The outcome variable was ADL score 6 months after baseline assessment. Multi-level linear regression was employed to explore the patient and organizational factors that affected ADL scores. Results: Of the patients, 45.4% had a baseline ADL score of between 31 and 40, with a score of 40 indicating that the patient was entirely dependent for all items. None of the organizational characteristics were significantly associated with effects on the ADLs of older adults who had been in a LTHC for at least 6 months. However, patient characteristics, such as age, baseline ADL, frequency of physical therapy, urinary incontinence, fecal incontinence, pressure ulcers, and having a tube or catheter, were significantly associated with ADL 6 months after baseline. Conclusion: In order to maintain and improve the ADL of older adults in LTCHs, we should develop strategies to prevent urinary and fecal incontinence, pressure ulcers, unnecessary tubes or catheters, providing adequate physical therapy. Additional studies should include more detailed information regarding nursing staff, including RN hours for direct care, education level and turnover.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.12
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• pp.155-160
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• 2003

Owing to the advances in ADC and DSP technologies, signals in If band, which once had to be processed in analog technology, can new be digitally processed. This is referred to as "Digital IF" or "Digital Radio", which is a preliminary stage of SDR. Applying the digital radio technology to a multi-carrier receiver design, a processing gain is generated through an over-sampling of input data. In the digital receiver, decimation is performed for reducing the computational complexity CIC and half band filter is used together with the decimation as an anti-alising filter. The CIC filter, however, should introduce the roll-off phenomenon in the passband, which causes the receiving performance to be considerably degraded due to the distorted Passband flatness of receiving filter. In this paper, we designed a CIC roll-off compensation filter for W-CDMA digital receiver. The performance of the proposed compensation filter is confirmed through computer simulations in such a way that the BER is minimized by compensating the roll-off characteristics.off characteristics.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.4
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• pp.442-450
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• 2014

This paper is a study of the propagation characteristic of matching liquids in the skin-covered breast model. In order to evaluate the matching liquids, we investigated six kinds of matching liquids applied to proposed 1-D breast model from frequency range of 3~6 GHz. A uniform plane wave is projected / transmitted inside the multi-layered breast model. Then the propagation characteristics inside the model and the transmission loss of each matching liquids were analyzed. The studying method presented in the paper can be used in the breast cancer detection system, the field of cancer detection using human tissue and the field of other medical devices. This paper was applied to the breast cancer detection system. Consequently, these studies could be used to determine the suitable type of matching liquids for breast cancer detection system and to apply useful for performance analysis.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.2 s.93
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• pp.154-160
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• 2005

Microwave Otters are essential device in modem wireless systems. A compact dimension BPF(Band-pass Filter) for IEEE 802.11a WLAN service is realized using LTCC multi-layer process. To extrude 2-stage band-pass equivalent circuit, band-pass and J-inverter transform applied to Chebyshev low-pass prototype filter. Because parallel L-C resonator is complicate and hard to control the inductor characteristics in high frequency, the shorted $\lambda/4$ stripline is selected for the resonator structure. The passive element is located in the different layers connected by conventional via structure and isolated by inner GND. The dimension of fabricated stacked band-pass filter which is composed of six layers, is $2.51\times2.27\times1.02\;mm^3$. The measured filter characteristics show the insertion loss of -2.25 dB, half-power bandwidth of 220 MHz, attenuation at 5.7 GHz of -32.25 dB and group delay of 0.9 ns at 5.25 GHz.

• Journal of Nutrition and Health
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• v.43 no.2
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• pp.161-170
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• 2010

We surveyed 837 students attending elementary schoolchildren in Korea for health functional foods (HFF) consumption and significant variables for their HFF consumption including demographic characteristics, parental health concern on offsprings, food eating frequency of subjects and beliefs on potential efficacy of HFF by subjects. The consumption prevalence of HFF was 45.9%, and among all types of HFF, nutritional supplements were taken most frequently, followed by apricot extract-fermented products > lactic acid bacteria containing products > EPA/DHA containing products > red ginseng products. HFF consumption was higher in subjects had parents of high education level (p < .05) and those from families with a high socioeconomic status (p < .01) in comparison to each corresponding group. Health concern on offsprings by parents (p < .001) and consumption ratio of HFF by family (p < .001) was higher in consumers than in nonconsumers of HFF. Total score of dietary assessment was higher in consumers than in nonconsumers of HFF (p < .01), and consumers had a more positive view concerning the potential efficacy of HFF than did nonconsumers (p < .001). Most consumers of HFF took HFF when they were healthy (42.5%), and they did not feel special effects through HFF consumption (47.7%). Most consumers of HFF got the information on HFF from family and relatives (24.8%), and most of them purchased HFF at pharmacy or oriental medicine clinics (53.9%). HFF consumers preferred multi-vitamins and Ca-supplements most among the vitamin mineral supplements belonged to HFF. Given the widespread consumption of HFF by elementary schoolchildren, the reasonable consumption of these products for the contribution to their overall health and well-being should be emphasized through nutrition education for them and their family.

• Journal of the Korea Society for Simulation
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• v.20 no.4
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• pp.157-166
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• 2011

As underwater environment monitoring system's interest has increased, the research is proceeding about underwater acoustic sensor network. Underwater sensor network can be applicable to many fields, such as underwater environment monitoring, underwater resource exploration, oceanic data collection, military purposes, etc. It is essential to define the PHY-MAC protocol for revitalization of the underwater acoustic sensor network which is available utilization in a variety of fields. However, underwater acoustic sensor network has to implement by consideration of underwater environmental characteristics, such as limited bandwidth, multi-path, fading, long propagation delay caused by low acoustic speed. In this paper, we define frequency of adjusted PHY protocol, network topology, MAC protocol, PHY-MAC interface, data frame format by consideration of underwater environmental characteristics. We also present system configuration of our implementation and evaluate performance based on our implementation with test in real underwater field.

• Journal of Korean Clinical Nursing Research
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• v.25 no.3
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• pp.251-264
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• 2019

Purpose: This study was a systematic review and meta-analysis to explore the factors related to quality of life in heart transplant recipients. Methods: To identify studies that suggested the factors related to the quality of life in heart transplant recipients, we searched the articles published from 1974 to November 2018 using Six databases, PubMed, CINAHL, EMBASE, Cochrane, KMBASE and RISS. A total of 22 studies were selected out of 5,234 for the systematic review and meta-analysis on the basis of the PRISMA flow. The quality of study was assessed by assessment tool form the NIH and meta-analysis was performed using the 'R 3.5.2' version to analyze the correlated effect sizes. Results: Factors related to quality of life in heart transplant recipients were categorized into six domains based on the health-related quality of life model introduced by Ferrans: individual, environmental, biological function, symptoms, functional status, and general health perception. In the meta-analysis, 34 factors were used and 17 factors having significant effect sizes were as follows: self-efficacy, demoralization, perceived control, current occupational status, age, marital status, health promotion life style in the individual characteristics; stress in environmental characteristics; physical function status, creatinine level, left ventricular ejection fraction (LVEF) in biological function; anxiety, depression, symptom frequency and distress in symptoms domain; coping, self-care compliance in functional status. Conclusion: The findings indicate that the multi-dimensional factors influencing the quality of life in heart transplant recipients and provide the evidence for developing effective interventions for improving the quality of life of recipients.