• Journal of the Institute of Electronics and Information Engineers
• /
• v.52 no.11
• /
• pp.12-19
• /
• 2015

In network-centric warfare, the communication network has played a significant role in defeating an enemy. Especially, the urgent and important data should be preferentially delivered in time. Thus, we proposed a priority MAC protocol based on CSMA/CA with Binary Exponential Back-off for tactical wireless networks. This MAC protocol suggested a PCW(Prioritized Contention Window) with differentiated back-off time by priority and a RBR(Repetitive Back-off Reset) to reset the remaining back-off time. The results showed that this proposed MAC has higher performance than those of DCF(Distributed Coordination Function) in the transmission success rate and the number of control packet transmission by reducing the packet collision. Thus, it produced more effective power consumption. In comparison with DCF, this proposed protocol is more suitable in high-traffic network.

• Translational and Clinical Pharmacology
• /
• v.26 no.4
• /
• pp.166-171
• /
• 2018

Although there are many commercially available training software programs for pharmacokinetics, they lack flexibility and convenience. In this study, we develop simulation software to facilitate pharmacokinetics education. General formulas for time courses of drug concentrations after single and multiple dosing were used to build source code that allows users to simulate situations tailored to their learning objectives. A mathematical relationship for a 1-compartment model was implemented in the form of differential equations. The concept of population pharmacokinetics was also taken into consideration for further applications. The source code was written using R. For the convenience of users, two types of software were developed: a web-based simulator and a standalone-type application. The application was built in the JAVA language. We used the JAVA/R Interface library and the 'eval()' method from JAVA for the R/JAVA interface. The final product has an input window that includes fields for parameter values, dosing regimen, and population pharmacokinetics options. When a simulation is performed, the resulting drug concentration time course is shown in the output window. The simulation results are obtained within 1 minute even if the population pharmacokinetics option is selected and many parameters are considered, and the user can therefore quickly learn a variety of situations. Such software is an excellent candidate for development as an open tool intended for wide use in Korea. Pharmacokinetics experts will be able to use this tool to teach various audiences, including undergraduates.

• The Journal of the Convergence on Culture Technology
• /
• v.7 no.3
• /
• pp.343-351
• /
• 2021

The purpose of this study was to identify the nursing students' COVID-19 vaccination intention based on health belief model. A total of 169 nursing students who were freshman to senior grade from one college participated in this study. An online self-administered questionnaire was used for data collection from April 5 to 16, 2021 and data were analyzed using the SPSS/Window 21.0 program. Multiple regression analysis conducted to verify the factors on COVID-19 vaccination intention. The significant influential factors for COVID-19 vaccination intention were self-efficacy(β=.345, p<.001), cues to action(β=.307, p<.001), perceived benefits(β =.143, p= .034), and knowledge(β=.116, p=.042). The model explained 50.8% of the variance in the COVID-19 vaccination intention. This result points to the importance of fostering nursing student's self-efficacy, cues to action, perceived benefits, and knowledge to promote COVID-19 vaccination uptake.

• Journal of the Korea Society of Computer and Information
• /
• v.27 no.10
• /
• pp.81-88
• /
• 2022

The purpose of this study is to present supporting data that can suggest a direction for sports advertisement strategy on social media by investigating how differences in social media engagement of sports advertisement affect users' product trust and purchase intention. To achieve this purpose, a total of 810 questionnaires, which were completed by sports-related college students engaged in social media activities using a method for writing a self-evaluation report, were collected, and 765 questionnaires were used as final valid samples after excluding 45 insincerely completed copies. For data processing, analyses of frequency, factor, reliability, correlation, and multiple regression were conducted using the Window SPSS (ver. 23.0) statistical program to draw the following conclusions. First, the social media engagement of the sports advertisement had a significant effect on the trust of the advertised products. Second, the social media engagement of the sports advertisement had a significant effect on the purchase intention of the advertised products. Third, the product trust acquired through the sports advertisement had a significant effect on the purchase intention.

• Korean Journal of Food Science and Technology
• /
• v.39 no.2
• /
• pp.122-127
• /
• 2007

In this study, an analytical method was optimized for detecting dioxin-like PCBs in fish and shellfish. Here, homogenized samples were extracted using an accelerated solvent extraction (ASE) system with 33 mL cell size. Multilayer column chromatography, which consisted of acidic, basic and neutral silica gels, was used for the clean up of the extracts. The instrumental analysis was executed by HRGC/HRMS to a resolution of 10,000 using 4 window multiple ion detection (MID) mode. For the results, the average recoveries ranged from 94.1 to 104.1% (${\pm}8.4$) and the limit of detection was approximately 0.1 pg/g at S/N ratio >3. Finally, the detected concentrations of dioxin-like PCBs for fish and shellfish were in the range of 0.030-1.836 pg TEQ/g.

• Journal of the Korean Applied Science and Technology
• /
• v.37 no.4
• /
• pp.1052-1065
• /
• 2020

This study analyzed the effects of professional baseball PPL advertising speed on brand awareness, brand attitude, and behavioral intention for professional baseball consumers. The purpose of this study is to present a method that can be used as a variety of marketing utilization strategies of professional baseball teams and parent companies. This study was conducted on 411 professional baseball consumers. For data processing, frequency analysis, reliability analysis, reliability analysis, and multiple regression analysis were performed using SPSS 25.0 Window Version. Then, the average variance extraction index (AVE) and construct validity (CR) were calculated to verify convergent validity and discriminant validity. In addition, confirmatory factor analysis (CFA) was performed using AMOS 25.0. As a result, first, it was found that entertainment, informativeness, and discomfort, which are sub-factors of PPL advertisement speed, have a significant effect on brand recognition. Second, entertainment, information, and discomfort, which are sub-factors of PPL advertising speed, have a significant effect on brand attitude. Third, entertainment, informativeness, and discomfort, which are sub-factors of PPL advertisement speed, have a significant effect on behavioral intention. Fourth, it was found that brand awareness and brand attitude have a significant effect on behavioral intention.

• Journal of KIISE:Databases
• /
• v.34 no.6
• /
• pp.483-492
• /
• 2007

Time series of conventional prediction techniques uses the model which is generated from the training step. This model is applied to new input data without any change. If this model is applied directly to stream data, the rate of prediction accuracy will be decreased. This paper proposes an stream data prediction technique using sliding window and regression. This technique considers the characteristic of time series which may be changed over time. It is composed of two steps. The first step executes a fractional process for applying input data to the regression model. The second step updates the model by using its information as new data. Additionally, the model is maintained by only recent data in a queue. This approach has the following two advantages. It maintains the minimum information of the model by using a matrix, so space complexity is reduced. Moreover, it prevents the increment of error rate by updating the model over time. Accuracy rate of the proposed method is measured by RME(Relative Mean Error) and RMSE(Root Mean Square Error). The results of stream data prediction experiment are performed by the proposed technique IMQR(Incremental Multiple Quadratic Regression) is more efficient than those of MLR(Multiple Linear Regression) and SVR(Support Vector Regression).

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.33 no.4A
• /
• pp.352-360
• /
• 2008

Recently Task Group (TG) 4 of the Institute of Electrical and Electronics Engineers (IEEE) 802.15a has been recommended a system with ranging capability in existence of multiple Simultaneous operating piconets (SOPs) as well as low-cost, low-power. According to the ranging service, coherent and non-coherent based ranging schemes using ternary code have been adopted as a standard. However it is hard to estimate an accurate time of arrival (TOA) in case of using direct sequence based TOA estimation method because pulse repetition interval (PRI) offered by TG is more limited than the maximum excess delay (MED) of channel. To mitigate inter pulse interference (IPI) problem, this paper proposes a non-coherent TOA estimation scheme using non-periodic transmission (NPT) pattern. The proposed receiver is based on a non-coherent energy detection considering with motivation of low rate wireless personal area network (LR-WPAN). TOA information is estimated via proper comparison with a prescribed threshold after the sliding correlation and search back window (SBW) process for reducing TOA error. To verify the performance of proposed ranging scheme, two distinct channel models approved by IEEE 802.15.4a TG are considered. According to the simulation results, we could conclude that the proposed scheme have performed better performance than the conventional method on the existence of multiple SOPs.

• 한국지구물리탐사학회:학술대회논문집
• /
• 2008.10a
• /
• pp.97-100
• /
• 2008

Mount Fuji is the focus of intense study because of its potential hazard signaled by seismic, geologic and historical activity. Based on extensive seismic data recorded in the vicinity of Mt. Fuji, coda quality factor ($Q_c^{-1}$) using a single scattering model hypothesis, and intrinsic and scattering quality factor $(Q_i^{-1}$ and $Q_s^{-1})$ using the Multiple Lapse Time Window Analysis (MLTW) method was measured. To focus the study on the magmatic structure below Mt. Fuji, to the data were separated into two groups: a near-Fuji region of rays traversing an area with radius 5 km around the summit (R < 5 km), and a far-Fuji region of rays beyond a radius of 20 km around the summit (R > 20 km). The results of the study have a small error range due to the large data sample, showing that all $Q^{-1}$ values in near-Fuji area are greater than those of far-Fuji area, and $Q_i^{-1}$ for both the near and far-Fuji area is higher than $Q_s^{-1}$ at high frequencies. The $Q_i^{-1}$ values of the near-Fuji area are lower than those of the other volcanic areas considered, while values of $Q_s^{-1}$ are not. The low $Q_i^{-1}$ for the volcanic region of near-Fuji suggests that the magmatic activity, or percent of partial melt, at Mt. Fuji is not as active as hot spot volcanoes such as Kilauea, Hawaii.

• Progress in Medical Physics
• /
• v.20 no.2
• /
• pp.72-79
• /
• 2009

Scatter correction for I-131 plays a very important role to improve image quality and quantitation. I-131 has multiple and higher energy gamma-ray emissions. Image quality and quantitative accuracy in I-131 imaging are degraded by object scatter as well as scatter and septal penetration in the collimator. The purpose of this study was to estimate scatter and septal penetration and investigate two scatter correction methods using Monte Carlo simulation. The gamma camera system simulated in this study was a FORTE system (Phillips, Nederland) with high energy, general-purpose, parallel hole collimator. We simulated for two types of high energy collimators. One is composed of lead, and the other is composed of artificially high Z number and high density. We simulated energy spectrum using a point source in air. We estimated both full width at half maximum (FWHM) and full width at tenth maximum (FWTM) using line spread function (LSF) in cylindrical water phantom. We applied two scatter correction methods, triple energy window scatter correction (TEW) and extended triple energy window scatter correction (ETEW). The TEW method is a pixel-by pixel based correction which is easy to implement clinically. The ETEW is a modification of the TEW which corrects for scatter by using abutted scatter rejection window, which can overestimate or the underestimate scatter. The both FWHM and FWTM were estimated as 41.2 mm and 206.5 mm for lead collimator, respectively. The FWHM and FWTM were estimated as 27.3 mm and 45.6 mm for artificially high Z and high density collimator, respectively. ETEW showed that the estimation of scatter components was close to the true scatter components. In conclusion, correction for septal penetration and scatter is important to improve image quality and quantitative accuracy in I-131 imaging. The ETEW method in scatter correction appeared to be useful in I-131 imaging.