• PNF and Movement
• /
• 제12권2호
• /
• pp.97-106
• /
• 2014

Purpose: The purpose of this study was to investigate changes in EEG through attention. Concentration training and performing tasks are important factors in the improvement of motor learning ability. Methods: In the experiment, 22 healthy people were divided into two groups: the trail making test (TMT) group and the computerized neurocognitive function test (CNT) group. A one-way Neuro Harmony M test to see whether there was a significant difference among the groups. Results: The TMT group showed a significant increase in ${\alpha}$ wave, ${\alpha}$ wave sequence, and ${\beta}$ wave sequence; however, there were no significant differences in SMR wave, SMR wave sequence, and ${\beta}$ wave. The CNT group showed increases in ${\alpha}$ wave, ${\alpha}$ wave sequence, SMR wave, SMR wave sequence, and ${\beta}$ wave sequence; however, there was no significant difference in ${\beta}$ wave. In EEGs before and after two performance tasks were changed, there were significant differences in ${\beta}$ wave, SMR wave, SMR wave sequence; however, there were no significant differences in ${\alpha}$ wave sequence, ${\beta}$ wave, and ${\beta}$ wave sequence. Conclusion: Attention training and concentration training offer feedback and repetition for constant stimulus and response. Moreover, attention training and concentration training can contribute to new studies and motivation by developing fast sensory and motor skills through acceptable visual and auditory stimulation.

• 대한화학회지
• /
• 제51권2호
• /
• pp.193-200
• /
• 2007

이 연구에서는 컴퓨터 보조 수업에서 상황맥락적인 피드백의 활용이 학생들의 개념 이해도, 과학 학습동기, 컴퓨터 보조 수업에 대한 인식에 미치는 효과를 조사하였다. 인천시의 한 남녀 공학 중학교에 있는 1학년 114명의 학생들을 상황맥락적 피드백 CAI, 피드백 CAI, CAI 집단에 배치하고, 8차시 동안 ‘물질의 세 가지 상태'와 ‘분자의 운동'에 대하여 수업을 실시하였다. 구획변인은 중간고사 과학 성적을 사용하였다. 이원 공변량 분석 결과, 사전 과학 성취 수준에 관계없이 상황맥락적 피드백 CAI 집단의 개념 이해도 점수가 다른 CAI 집단에 비해 높았고, 그 점수 차이가 통계적으로 유의미하였다. 상위 학생들의 경우 피드백 CAI 집단의 과학학습 동기 점수가 CAI 집단의 점수보다 통계적으로 유의미하게 높았으나, 하위 학생들의 경우에는 세 집단 간 점수 차이가 통계적으로 유의미하지 않았다. 컴퓨터 보조 수업에 대한 인식의 경우, 상황맥락적 피드백 CAI 집단과 피드백 CAI 집단의 상위 학생들은 CAI 집단의 상위학생에 비해 컴퓨터 보조 수업에 대해 긍정적으로 인식하였다. 피드백 CAI 집단의 하위 학생들은 다른 두 CAI 집단보다 부정적인 인식이 약간 높았다. 교육학적 함의를 논의하였다.

• 한국통신학회논문지
• /
• 제33권8C호
• /
• pp.617-626
• /
• 2008

기회적 빔포밍(OBF)은 채널이 거의 변하지 않는 환경에서도 기지국에서 랜덤 빔을 발생시켜서 인위적으로 다중 사용자 다이버시티 이득을 얻는 기법이며, 궤환 정보량도 순시 SNR 정보만을 필요로 한다. 이러한 이점에도 불구하고 수신단에서의 채널 추정 오류는 부정확한 순시 SNR의 원인이 된다. 특히 추정된 SNR에 의해 선택된 AMC 레벨이 실제 채널 용량보다 큰 전송율을 요구할 때는 패킷의 손실이 불가피 하다. 본 논문에서는 채널 추정 성능을 고려하여 계산한 보수적 인자를 이용해 추정된 SNR을 인위적으로 감소시킴으로써 성능 저하를 방지하는 보수적 링크 적응 방식을 제안한다. 제안된 보수적 인자는 실제 채널 SNR과 감소된 추정 SNR의 차이의 최대값의 분산을 최소화 하도록 계산된다. 이를 위해 실제 채널 SNR과 추정된 SNR의 차이의 통계량을 수학적으로 분석하였다. 실제 LS 추정기를 적용한 컴퓨터 시뮬레이션 결과 채널 추정 오류가 있는 상황에서 제안된 방식이 추정 오류로 저하된 평균 수율 성능을 두 배 이상 향상시키고, 비례적 공정 스케줄러의 공평성 성능을 손상시키지 않음도 확인하였다.

• 한국정보시스템학회지:정보시스템연구
• /
• 제17권3호
• /
• pp.205-233
• /
• 2008

This study suggests the dynamic value chain model, that will be able to not only show changing processes to organization's significant capital by integrating an individual, implicit, and explicit knowledge which affect organizational decision making, but also distinguish the key driver for raising organizational competitive power because it makes possible to analyze sensitivity of performance along with decision making alternatives and policy changes from dynamic view by connecting knowledge management capability, knowledge management activity, and relations with organizational performance with specific strategic map. Recently, a lot of organizations show interest in measuring and evaluating their performance synthetically. In organizations taking knowledge management, they introduce effective value chain model like a dynamic balanced scorecard (DBSC), and therefore they can reflect their knowledge management condition as well as show their changes by checking performance of established vision and strategy periodically. Furthermore, they can ask for their inner members' understanding and participation by communicating with and inspiring their members with awareness that members are one of their group, present a base of benchmarking, and offer significant information for later decision making. The BSC has been a successful framework for measuring an organization's performance in various perspectives through translating an organization's vision and strategy into an interrelated set of key performance indicators and specific actions. The BSC, while having significant strengths over traditional performance measurement methods, however, has its own limitations, due to its static nature, such as overlooking two-way causation between performance indicators and neglecting the impact of delayed feedback flowing from the adoption of new strategies or policy changes. To overcome these limitations, this study employs SD, a methodology for understanding complex systems where dynamic feedback among the interrelated system components significantly impact on the system outcomes. The SD simulation model in the form of DBSC would serve as a useful strategic teaming tool for facilitating an organization's communication process through various scenario analyses as well as predicting the dynamic behavior pattern of their key performance measures over a future time frame. For the demonstration purpose, this study applied the DBSC model to Prototype of Korea manufacturing and service firm.

• 한국자동차공학회논문집
• /
• 제7권9호
• /
• pp.36-47
• /
• 1999

Three-way catalyst converter, cleaning up the exhaust gas contamination of SI engine, has the best efficiency when A/F ratio is near the stoichiometry . The feedback control using oxygen sensors in the exhaust manifold has limits caused by the system delays. So the accurate measurement of air flow rate to an engine is essential to control the fuel injection rate especially on transient condition like the rapid throttle opening and closing. To measure the rapid change of flow rates. the air flow meter for the engine requires quick response, flow reversal detection, and linearity . Tjhe proposed integration type air flow meter (IFM), composed of an ultrasonic flow meter with an integration circuit, has significantly improved the measurement accuracy of air mass inducted through the throttle body. The proposed control method estimated the air mass at the cylinder port using the measured air mass at the throttle . For the fuel dynamic model, the two constant fuel model is introduced . The control parameters from air and fuel dynamics are tuned to minimize the excursion of the air fuel ratio. As a result A/F ratio excursion can be reduced within 5% when throttle rapidly opens and closes at the various engine conditions.

• 대한안전경영과학회지
• /
• 제3권3호
• /
• pp.151-164
• /
• 2001

Currently, there are little evaluated model for each industry and systematic analysis for each item about current business web sites. And the approach way to improve it all depends on individual. This research is about two different points of view on I-Evaluation development as an approach method to provide analysis, evaluation, and guideline on business web sites. The one is about developing a working step and a site evaluation model that are necessary to improve the quality of site. The other is about a framework development to apply a feedback on site most rapidly and site optimization. The former is from the methodological point of view for I-Evaluation, and the latter is from the point of view for I-Evaluation Framework. In terms of methodology, developing site evaluation model and defining a working step belong to it. Site evaluation model means customizing each customers web site, using each evaluated scoring model which can be a standard for each industry to analyze a similar business web site. Defining a working step means defining input and output parameters for composed elements, working processes, and results analysis on an evaluated model. And also it includes building a working environments to automatic steps mentioned the above by clarifying them.

• 한국조리학회지
• /
• 제10권2호
• /
• pp.59-71
• /
• 2004

This study .is about marketing of menu-delivery-web site through internet which is getting bigger in working-together-couples. The purpose of this study is suggesting the way which can make internet marketing to activate by means of analysing of a certain enterprise's homepage with marketing mix method. We draw the findings which is seperated by goods, price, promotion, distribution, other service according to marketing constituents. As a result of research, it was found that each company has given much more weight on some part in internet marketing's field of activity. In general, they put an empasis on activity of goods and promotion. On the other hands they didn't consider prices and delivery to be important compared with other parts. In a field of price, menu-site just announced price but in further advance, it had better offer and compare two price level when customer used menu-delivery-web site or not. And that site needed to promote and to be advertised what customer who just think using web site was expensive have benefit in the price. One of the most important things about internet-marketing was that fast and exact feedback and community made each enterprise to be able to help to communicate with customer. For these strategy to execute effectively, first company's name should be known well and goods and service the company had should be well advertised. But first of all, differentiated strategy should precede through consistency of taste and quality, consistant information update as a internet-company and sincere homepage management.

• 한국정밀공학회지
• /
• 제9권3호
• /
• pp.73-82
• /
• 1992

An industrial robot, installed real manufacturing processes an element of the system autmation, can be considered as an uncertain system due to dynamic uncertainties in inertial parameters and varying payloads. Most difficuties in controlling a robot manipulator are caused by the fact that the dynamic equations describing the motions of the manipulator are inherently nonlinear and heavily coupled effects between joints and associated links. Existing robot conrol systems have constant predefined gains and do not cover the complex dynamic interactions between manipulator joints. As a result, the manipulator is severly limited in range of application, speed of operation and variation of payload. The proposed controller is operated by adjusting its gains based on the response of the manipulator in such a way that the manipulator closely matches the reference model trajectories defined by the desinger. The proposed manipulator studied has two loops, an inner loop of model reference adaptive controller and an outer loop of state feedback controller with integral action to guarantee the stability of the adaptive scheme. This adaptation algorithm is based on the hyperstailiy approach with an improved Lyapunov function. The coupling among joints and the nonlinearity in the dynamic equation are explicitly considered. The designed manipulator controller shows good tracking performance in practical working environment, various load variations and parameter uncertainties.

• 의학교육논단
• /
• 제18권3호
• /
• pp.156-166
• /
• 2016

Medical school students learn a lot about medical knowledge and clinical experience in the classroom. Teaching is a main focus in medical schools; therefore, it is necessary to identify the characteristics of good teaching. The aim of this study is to analyze the characteristics of high-quality education in medical schools. In this study, in-depth interviews were conducted over two weeks on twelve fourth-year medical students. Participants were asked to define high-quality education, list the general ways in which high-quality classes are delivered, mention cases where they have experienced high-quality teaching, and describe the attitude required of students to make high-quality education possible. The results showed that students want to be taught in an interactive way on the core content needed in an actual clinical setting for the goal of cultivating primary care physicians. They want their education to include not only medical knowledge, but also liberal art subjects such as politics, economics, sociology, culture and ethics education to help instill a sound value system. In particular, students stressed the importance of instructors delivering appropriate post-evaluation feedback, and they also emphasized that learner mindset and attitude is important in supporting high-quality teaching in class. This paper also summarizes the elements of high-quality teaching in terms of educational goals, content, and method, and examines cases of instructors who have delivered high-quality classes.

• 한국정보처리학회:학술대회논문집
• /
• 한국정보처리학회 2011년도 추계학술발표대회
• /
• pp.1174-1176
• /
• 2011

Unfortunately, the number of blind people increases every 5 seconds in our world. An extensive research was made on improving the conventional walking cane and developing a microcontroller based walking stick for the blind with sensors and a feedback in form of vibration. Two different kinds of sensors are used to detect obstacles, ultrasonic and infrared distance sensors. The signal from an ultrasonic sensor is fed to a microcontroller. With the help of the supporting software, the Pulse Width Modulation (PWM) principle is extensively used to form three zones and run the corresponding vibration motor at different spends according to how far the detected object is located. The other infrared distance sensors are connected to amplifiers and after that to their corresponding vibration motors through motor drivers. The vibration motors are to be located around the user's arm to notify the blind of the obstacles in the intended walking way. It can be very reliable and sufficient device guiding the blind other than the conventional walking cane which has many drawbacks which will be explained and discussed.