• Journal of Biomedical Engineering Research
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• v.28 no.5
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• pp.636-646
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• 2007

Adequate postural control depends on the spatial and temporal integration of vestibular, visual, and somatosensory information. Especially, the musculoskeletal function is essential to maintain the postural control. The experimental studies was performed on the muscular activities in the lower extremities during maintaining and moving exercises on an unstable platform with Magneto Rheological(MR) dampers. The unstable platform of the developed system was controlled by electric currents to the MR dampers. A subject executed the maintaining and moving exercises which are presented through the display monitor. The electromyographies of the eight muscles in lower extremities were recorded and analyzed in the time and the frequency domain: the muscles of interest were rectus femoris(RF), biceps femoris(BF), tensor fasciae latae(TFL), vastus lateralis(VL), vastus medialis(VM), gastrocnemius(Ga), tibialis anterior(TA), Soleus(So). The experimental results showed that the muscular activities differed in the four moving exercises and the nine maintaining exercises. For the anterior-posterior pattern, the TA showed highest activities; for the left-right pattern, the TFL; for the 45, $-45^{\circ}$ pattern, the TFL and TA. Also, the rate of the increase in the muscular activities were affected by the condition of the unstable platform with MR dampers for the maintaining and moving exercises. The experimental results suggest that the choice of different maintaining and moving exercises could selectively train different muscles in various intensity. Futhermore, the findings suggested that the training using this system can improve the ability of postural control.

• Nutrition Research and Practice
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• v.4 no.1
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• pp.36-42
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• 2010

A cross-sectional survey was used to investigate the rates of overweight and obesity (BMI$\geq$25), and eating attitudes among college students. Data were collected at a large southeastern university. Adolescents (ages 18-25) self-reported weight and height (to calculate BMI), and, in addition to demographic information, completed the eating attitudes (EAT 26) scale to assess dieting tendencies. Significance of the mean BMI differences between gender and ethnic background were assessed by one-way analysis of variance (one-way ANOVA). Chi-square was used to determine whether the rate of those with BMI$\geq$25 between gender and ethnic background was statistically significant. While 52.7% of the students' BMI were within the normal weight category, 15.2% were underweight, 21.3% were overweight, and 10.8% were obese. The rate of BMI$\geq$25 differed by gender and ethnicity, with males and African Americans having higher rates. About 12 % of the participants reported disturbed eating behavior, which is lower than previously reported. Even so, results support the generally held belief that disturbed eating attitudes and unhealthy dieting are common among college students, especially among females. At the same time, disturbed eating attitudes are not just the domain of young female students; about 10% of college males reported disturbed eating attitudes. Findings of this study call for obesity prevention/intervention and lifestyle modification outreach programs among college students. Weight status and unhealthy eating behaviors of college. students should be a concern to health care professionals. While obese young adults will likely remain obese throughout their adult life, excessive dieting among students, which is linked to eating disorders and other health hazards, does not provide healthy and adequate alternatives for maintaining a normal BMI. Implications for obesity prevention programs are discussed.

• Proceedings of the Korea Contents Association Conference
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• 2003.05a
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• pp.117-126
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• 2003

A semiotic approach to modern visual arts has emerged since French post-structuralism was introduced to Anglo -American academics by "deconstruction" or "postmodernism." It views a work of art as a sign, which is its methodical assumption ana at the same time makes its application more accessible In the milieu of modern visual arts'effort to be intimate to with general audience, modern art photography is now faced with the request to be a familar and universal domain instead of being left only in photo books as artistic and academic achievements More specifically, various photo images 1mm such visual media as newspapers TVs, and computer graphics to such megaexhibitions as "Gwangju Biennale," "Media City Seoul," and "Pusan International Art Festival," are main objects of s030y. A coherent and scientific analysis of visual semitotics is still on the way; however, it is an urgent task how to read and interpret a photo image with multiple meanings This study argues that visual semiotics can be a powerful tool to enhance the understanding of art photography. After all, semiotics is a product of age; we live in the age of legibility, that is, of reading the work of art well as the social events and phenomena.rk of art well as the social events and phenomena.

• Journal of Biomedical Engineering Research
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• v.10 no.3
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• pp.253-260
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• 1989

The time domain methods of estimating the attenuation coefficient are generally based on the analysis of statisical properties of the reflected echoes form an attenuating medium. Hence, it is often required to have a large number of data samples in order to obtain a statistically stable estimation result. In the attenuation estimation problem, this means that many different speckle patterns are required in the spatial resolution volume of an attenLlation image. In this paper, by using the fact that the speckle pattern Is sensitive to the point spread function of the ultrasound beam, we suggest a method to generate the statiscally uncorrelated or slightly correlated data samples in a given region by rotating a linear transducer and carrying out lateral scans for all rotating angles. This technique is applied to the entropy method for attenuation estimation proposed recently by the authors where the performance is verified by experiments using a tissue equivalent phantom.

• Journal of the Korea Society for Simulation
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• v.25 no.2
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• pp.41-49
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• 2016

Counter Fire Operations can be characterized as having a system of systems that key features include situational awareness, command and control systems and highly responsive strike achieved by precision weapons. Current modeling methodology cannot provide an appropriate methodology for a system of systems and utilizes modeling and simulation tools to implement analytic options which can be time consuming and expensive. We explain developing methodology and tools for the effectiveness analysis of the counter fire operations under Network Centric Warfare Environment and suggest how to support a efficient decision making with the methodology and tools. Theater Counter Fire Operations tools consist of Enemy block, ISR block, C2 block and Shooter block. For the convenience of using by domain expert or non simulation expert, it is composed of the environments that each parameter and algorithm easily can be altered by user.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.5
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• pp.831-838
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• 2016

The disaster preventing system using vegetation has been growing in the field of coastal engineering in recent years. To analyze wave and flow fields under nonlinear interactions between tsunami and vegetation, the purpose of this study is to evaluate newly-developed 3-D numerical wave tank including energy dissipation by tsunami-vegetation interaction based on existing N-S solver with porous body model. Comparing numerical results using mean drag coefficient and dynamic drag coefficient due to Reynolds number to existing experimental results it is revealed that computed results considering the dynamic drag coefficient are in good agreement with the laboratory test results for time-domain waveform. In addition, the calculated transmission coefficients of solitary waves in various vegetation densities and incident wave heights are also in good agreement with the experimental values. This confirms the validity and effectiveness of the developed 3-D numerical wave tank with the fluid resistance by vegetation.

• The Korean Journal of Malacology
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• v.29 no.2
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• pp.155-161
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• 2013

Cathepsins are lysosomal/cysteine proteases belong to papain family (C1 family) that is involved in intracellular protein degradation, antigen processing, hormone maturation, and immune responses. In this study, member of cathepsin family was identified from Manila clam (Mc-Cathepsin D) and investigated the immune response against brown ring disease (BRD) causing Vibrio tapetis challenge. The identified Mc-Cathepsin D gene encodes characteristic features typical for the cathepsin family including eukaryotic and viral aspartyl protease signature domain and two highly conserved active sites ($^{84}VVFDTGSSNLWV^{95}$ and $^{270}IADTGTSLLAG^{281}$). Moreover, MC-Cathepsin D shows higher identity values (-50-70%) and conserved amino acids with known cathepsin D members. Transcriptional results (by quantitative real-time RT-PCR) showed that Mc-Cathepsin D was expressed at higher levels in gills and hemocytes than mantle, adductor muscle, foot, and siphon. After the V. tapetis challenge under laboratory conditions, Mc-Cathepsin D mRNA was up-regulated in gills and hemocytes. Present study indicates that Mc-Cathepsin D is constitutively expressed in different tissues and potentially inducible when infecting BRD by V. tapetis. It is further suggesting that Mc-Cathepsin D may be involved in multiple role including immune response reactions against BRD.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.5
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• pp.410-418
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• 2017

Results of an analysis of the continuous motion effect for FMCW-SAR system and a signal processing to correct it are presented in this paper. SAR images reconstructed by back-projection algorithm are included as well. To analyze how platform velocity and sampling frequency affect the continuous motion effect, FMCW signal model was used, and the signal processing in time-doppler(t, $k_u$) domain was adopted. Then, back-projection algorithm and modified matched-filter was used to reconstruct SAR images, and it was validated using measured data by airborne FMCW-SAR system in X-band frequency.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.10 no.4
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• pp.479-486
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• 1999

In this paper the system performance degradation resulting from nonlinear transmitter power amplifier which is essential to increase the efficiency is analyzed in a forward link CDMA system. The power amplifier is modeled by power series model which includes only odd-order terms. The effects of power amplifier's nonlinearity such as intersymbol interference, phase distortion on the RF system performance were visualized by examining the distorted time domain waveforms, signal vector constellation. And through the investigation of the power spectrum density of the transmitted signal, spectral regrowth or sideband regrowth which is result from amplitude distortion can be seen. All these characteristics result in BER performance degradation due to other user interferences and intersymbol interference. The analysis technique described here applies not only to power amplifier but also to any other nonlinear components such as mixers and switches. Also the effects of adjacent channel interference and supurious emission can be analysed between different systems.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.12C
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• pp.1257-1264
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• 2006

The carrier frequency offset causes loss of orthogonality between sub-carriers, thus leads to inter-carrier interference (ICI) in the OFDM symbol. This ICI causes severe degradation of the BER performance of the OFDM receiver. In this paper, we propose a new ICI cancellation algorithm which estimates frequency offset at the time-domain by using CP-ICA method to the received sub-carriers phase rotation. This algorithm is based on a statistical blind estimation method, which mainly utilizes the EVD, rotating phase and the $4^{th}-cumulants$. Since our scheme does not need any training and pilot symbol in estimation, we can expect enhanced bandwidth efficiency in OFDM systems. Simulation results show that the proposed frequency offset estimator is more accurate than the other estimators in $0.0<\varepsilon<1.0$.