• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.42 no.2 s.302
• /
• pp.151-160
• /
• 2005

In this paper, we propose a new fast motion estimation algorithm based on successive elimination algorithm (SEA) which can dramatically reduce heavy complexity of the variable block size motion estimation in H.264 encoder. The proposed method applies the conventional SEA in the hierarchical manner to the seven block modes. That is, the proposed algorithm can remove the unnecessary computation of SAD by means of the process that the previous minimum SAD is compared to a current SAD for each mode which is obtained by accumulating sum norms or SAD of $4\times4$ blocks. As a result, we have tighter bound in the inequality between SAD and sum norm than in the ordinary SEA. If the basic size of the block is smaller than $4\times4$, the bound will become tighter but it also causes to increase computational complexity, specifically addition operations for sum norm. Compared with fast full search algorithm of JM of H.264, our algorithm saves 60 to $70\%$ of computation on average for several image sequences.

• Journal of the Institute of Electronics Engineers of Korea SC
• /
• v.45 no.3
• /
• pp.32-41
• /
• 2008

In this paper, we describe the synthesis of robust and non-fragile $H^{\infty}$ state feedback controllers for linear systems with affine parameter uncertain tracking servo system of blu-ray disc drive, as well as static state feedback controller with polytopic uncertainty Similarity any other control system, the objective of the track-following system design for optical disc drives is to construct the system with better performance and robustness against modeling uncertainties and various disturbances. Also, the obtained condition can be rewritten as parameterized linear matrix inequalities(PLMIs), that is, LMIs whose coefficients are functions of a parameter confined to a compact set. We show that the resulting controller guarantees the asymptotic stability and disturbance attenuation of the closed loop system in spite of controller gain variations within a resulted polytopic region.

• Journal of Advanced Navigation Technology
• /
• v.23 no.6
• /
• pp.577-583
• /
• 2019

A dynamic system is called positive if any trajectory of the system starting from non-negative initial states remains forever non-negative for non-negative controls. In this paper, we consider the new stability condition for the positive time-varying linear discrete interval systems with time-varying delay and unstructured uncertainty. The delay time is considered as time-varying within certain interval having minimum and maximum values and the system is subjected to nonlinear unstructured uncertainty which only gives information on uncertainty magnitude. The proposed stability condition is an improvement of the previous results which can be applied only to time-invariant systems or had no consideration of uncertainty, and they can be expressed in the form of a very simple inequality. The stability conditions are derived using the Lyapunov stability theory and have many advantages over previous results using the upper solution bound of the Lyapunov equation. Through numerical example, the proposed stability conditions are proven to be effective and can include the existing results.

• Journal of KIISE:Software and Applications
• /
• v.31 no.10
• /
• pp.1304-1319
• /
• 2004

We can significantly reduce the cost o# program testing by automating the process of test data generation. Test data generation usually concerns identifying input values on which a selected path is executed. Although lots of research has been done so far, there still remains a lot of issues to be addressed. One of the issues is the shape problem. The shape problem refers to the problem of figuring out a shape of the input data structure required to cause the traversal of a given path. In this paper, we introduce a new method for the shape problem. The method converts the selected path into static single assignment (SSA) form without pointer dereferences. This allows us to consider each statement in the selected path as a constraint involving equality or inequality. We solve the constraints to get a solution which will be represented in terms of the points-to relations for each input variable. Simple, but illustrative examples are given to explain the proposed method.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.19 no.3
• /
• pp.337-342
• /
• 2009

This paper concerns delay-range-dependent robust stability and stabilization for time-delay nonliner system via T-S fuzzy model approach. The time delay is assumed to be a time-varying continuous function belonging to a given range. On the basis of a novel Lyapunov-Krasovskii functional, which includes the information of the range, delay-range-dependent stability criteria are established in terms of linear matrix inequality. It is shown that the new criteria can provide less conservative results than some existing ones. Moreover, the stability criteria are also used to design the stabilizing state-feedback controllers. Numerical examples are given to demonstrate the applicability of the proposed approach.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.37 no.7
• /
• pp.18-23
• /
• 2000

An active phased away antenna consists of many channels including radiator and active circuitary that contains low noise amplifiers and phase shifters. Each channel has different initial phase shift and gain because of inequality in active circuitary itself, interface between radiator and active circuitary, beam forming network and other antenna configurations. This is an inherent problem in active phased away antenna, therefore each channels' initial phase shifts and gains should be calibrated for obtaining the designed radiation pattern and antenna gain. In this paper, an efficient calibration method for the active phased array antenna is presented. By performing the above method, thhe antenna gain is increased more than 2.0 dB after calibrating considerably unequal 12 channels' initial phase shifts and gains.

• Journal of Advanced Navigation Technology
• /
• v.23 no.5
• /
• pp.424-429
• /
• 2019

The evolution of networking technology such as commercialization of 5G systems provides foundation for information exchange and control of systems over the network. In addition, importance of controlling a system with delay is increasing significantly, since various phenomena in the network are associated with delay. In this paper, with a predictive control which has been studied for designing a controller with low complexity, we propose a novel predictive control for a system with multi-inputs such that it can keeps the complexity almost the same regardless of the number of inputs and degree of delay. The asymptotic stability of the proposed control with a static output feedback is also proved. The numerical simulation shows that the proposed method is superior in complexity and the performance of finding feasible controllers to the existing predictive control and a conventional method based on augmented states.

• Journal of Convergence for Information Technology
• /
• v.9 no.3
• /
• pp.36-43
• /
• 2019

The purpose of this study is the preliminary inequality experiment study of control group to confirm the effects of convergence education by jigsaw model and flipped learning in nursing students. The subjects of this study were 81 students who participated in Integrated Practice II of the 3rd grade of Nursing Science in J area and data were collected using the questionnaire before and after the convergence education. As a result of the study, it was found that convergence education by jigsaw model and flipped learning was significant in learning satisfaction(t=-3.783, p=.001). Therefore, convergence education by jigsaw model and flipped learning as a teaching and learning method is expected to improve the learning satisfaction and maximize the learning outcome, so this study is meaningful as the basic data itself. Based on these results, it is necessary to develop and apply the teaching - learning program that combines jigsaw model with flipped learning.

• The Journal of Fisheries Business Administration
• /
• v.52 no.4
• /
• pp.13-28
• /
• 2021

The purpose of this study is to compare short-term price predictive power among ARMA ARMAX and VAR forecasting models based on the MDM test using monthly consumer price data of frozen mackerel. This study also aims to help policymakers and economic actors make reasonable choices in the market on monthly consumer price of frozen mackerel. To analyze this study, the frozen wholesale prices and new consumer prices were used as variables while the price time series data were used from December 2013 to July 2021. Through the unit root test, it was confirmed that the time series variables employed in the models were stable while the level variables were used for analysis. As a result of conducting information standards and Granger causality tests, it was found that the wholesale prices and fresh consumer prices from the previous month have affected the frozen consumer prices. Then, the model with the highest predictive power was selected by RMSE, RMSPE, MAE, MAPE, and Theil's inequality coefficient criteria where the predictive power was compared by the MDM test in order to examine which model is superior. As a result of the analysis, ARMAX(1,1) with the frozen wholesale, ARMAX(1,1) with the fresh consumer model and VAR model were selected. Through the five criteria and MDM tests, the VAR model was selected as the superior model in predicting the monthly consumer price of frozen mackerel.

• Korean Journal of Clinical Pharmacy
• /
• v.32 no.4
• /
• pp.288-302
• /
• 2022

Objective: Community pharmacists are frontline health care providers, but have been considered as underutilized professionals on a daily basis. The purpose of this scoping review was to identify information about the impact of the COVID-19 pandemic on community pharmacy services and to evaluate new services that could be applicable. Methods: We searched MEDLINE and EMBASE for studies published up to January 10, 2020. Search terms consisted of keywords relevant to this review, including "COVID-19", "community pharmacy", and "community pharmacist". This review targeted studies of pharmacist services provided by community pharmacies in OECD member countries during the COVID-19 pandemic period. Results: Twenty-seven studies were included in this review. Changes in community pharmacist services due to the COVID-19 pandemic were broadly classified into four categories. First, as the face-to-face services became challenging, various non-face-to-face services were being tried. Second, community pharmacists directly participated in the services to prevent the spread of COVID-19. Third, community pharmacists made efforts to support continuity of care for patients who experienced difficulties due to the reduced professional care as health and medical resources are concentrated in response to COVID-19. Fourth, community pharmacist services were emerging, targeting patients suffering from greater health inequality during the pandemic. Patients expressed high demand and satisfaction for the service of the community pharmacist, and pharmacists reported self-efficacy and professional pride. Conclusion: This study demonstrated that in the era of the COVID-19 pandemic, various community pharmacist services have been tried and received positive evaluations from patients in several OECD countries.