• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.2
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• pp.183-188
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• 2014

In this paper, the propagation effect of power supply uncertainty on the output of class-F power amplifier has been estimated. Also, a 1.9 GHz, 10 watt class-F power amplifier was measured to verify the estimation and to find the optimal biasing point. By approximating the propagation theory of uncertainties, the propagation effect of bias uncertainty was mathmatically calculated. As a result, the DC biases have propagated uncertainties of 15~70 mW. However, at the optimized bias point, the uncertainty in the output power could be dropped less than 15 mW while the output power has dropped by 0.37 dB.

• Journal of Korean Academy of Nursing
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• v.20 no.1
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• pp.79-87
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• 1990

Clinical and epedemiologic studies of coronary heart disease(CHD)have from time to time over the last three decades found associations between prevalence of CHD and behavioral attributes and cigarette smoking. The main purpose of this study is reduced to major risk factor of coronary heart disease through prohibition of smoking and control of behavior pattern. The subjects consisted of 120 smokers and 90 non-smokers who were married men older than 30 years working in officers. The officers were surveyed by means of questionnaire September 26 through October 6, 1989. The Instruments used for this study was a self-administered measurement tool composed of 59 items was made through modifications of Jenkuns Activity Survery(JAS). The Data were analysed by SAS(Statistical Analsis System) program personal computer. The statistical technique used for this study were Frequency, x$^2$-test, t-test, ANOVA, Pearson Correlation Coefficient. The 15 items were chosen with items above 0.3 of the factor loading in the factor analysis. In the first factor analysis 19 factors were extracted and accounted for 86% of the total variance. However when the number of factors were limited to 3 in order to derive Jenkins classification, three factors were derived. There names are Job-Involvement, Speed & Impatience, Hard-Driving. Each of them includes 21 items, 21 and 9, respectively. The results of this study were as follow : 1. The score of the smoker group and non-smoker group in Job-Involvement(t＝5.7147, p＜0.0001), Speed & Impatience(t＝4.6756, p＜.0001), Hard-Driving(t＝8.0822, p＜.0001) and total type A behavior pattern showed statistically significant differences(t＝8.1224, p＜.0001). 2. The score of type A behavior pattern by number of cigarettes smoked daily were not statistically significant differences. 3. The score of type A behavior pattern by duration of smoking were not significant differences. It was concluded that the relationship between smokers and non - smokers of type A behavior pattern was statistically significant difference but number of cigarettes smoked daily and duration of smoking were not significant differences. Therefore this study is needed to adequate nursing intervention of type A behavior pattern in order to elevated to educational effect for prohibition of cigarette smoking.

• Journal of Family Resource Management and Policy Review
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• v.18 no.2
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• pp.121-141
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• 2014

The purpose of this research is to determine how effective individual resources, family resources and developed environmental resources are in assisting the adaptation of a single parent's child to school life. The subjects were 284 first-year middle-school students with a single parent who were included in the first year of the Korean Children and Youth Research Panel 2010 data. The data were statistically processed using SPSS 18.0software. The results were as follows. First, the research participants' adaptation to school life, self-esteem, self-resilience, and peer relations were all shown to have an average of higher than 2 on a 4-point scale. Positive perceptions of parenting attitudes were 2.87, and negative perceptions 2.38. Computer usage was high, scoring 2.42, but mobile phone usage was average, at 2.02. Of the participants, 83.8% did not participate in a club or extracurricular activity. Second, self-esteem, self-resilience, peer relations, and positive parenting attitudes were correlated positively with adaptation to school life, but relying on a mobile phone was correlated negatively. Third, regarding the consequences of the relative effectiveness of the variables for adaptation to school life, as self-esteem, self-elasticity, and positive perceptions of parenting attitudes increased, Adaptation of a single parent's child to school life was more successful. Additionally, as annual family income and reliance on mobile phones increased, students' adaptation to school was less successful.

• Journal of the Korean Institute of Intelligent Systems
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• v.24 no.6
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• pp.657-664
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• 2014

In this paper, we described evaluation software that can propose rating scale and evaluate automatically on SDR(Software-Defined Radio) transmitter system. To deduct suitable rating scale, we extracted requirements based on the operating environment, operating application and operating method because SDR operating software is subordinative to the hardware. And we implementation evaluation software to automatically quality evaluation using rating scale draw from the requirements. The implemented evaluation software has automatically evaluation functions using script, can update the evaluation factor and show visual evaluation result. The implemented evaluation software is used to useful the high quality SDR operating software development.

• Journal of the Korean Institute of Intelligent Systems
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• v.24 no.6
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• pp.609-614
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• 2014

Cerebellar ataxia is a steadily progressive neurodegenerative disease associated with loss of motor control, leaving patients unable to walk, talk, or perform activities of daily living. Direct motor instruction in cerebella ataxia patients has limited effectiveness, presumably because an inappropriate closed-loop cerebellar response to the inevitable observed error confounds motor learning mechanisms. Recent studies have validated the age-old technique of employing motor imagery training (mental rehearsal of a movement) to boost motor performance in athletes, much as a champion downhill skier visualizes the course prior to embarking on a run. Could the use of EEG based BCI provide advanced biofeedback to improve motor imagery and provide a "backdoor" to improving motor performance in ataxia patients? In order to determine the feasibility of using EEG-based BCI control in this population, we compare the ability to modulate mu-band power (8-12 Hz) by performing a cued motor imagery task in an ataxia patient and healthy control.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.2
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• pp.415-420
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• 2016

A graph G=(V,E) is called an interval graph with a set V of vertices representing intervals on a line such that there is an edge $(i,j){\in}E$ if and only if intervals i and j intersect. In this paper, we are concerned in the vertex connectivity, one of various characteristics of the graph. Specifically, the vertex connectivity of an interval graph is represented by the overlapping of intervals. Also we propose an efficient algorithm to compute the vertex connectivity on the fully dynamic environment in which the vertices or the edges are inserted or deleted. Using a special kind of interval tree, we show how to compute the vertex connectivity and to maintain the tree in O(logn) time when a new interval is added or an existing interval is deleted.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.05a
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• pp.69-70
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• 2017

As the industry develops, the size of buildings and ships are getting bigger and more complicated. In such a complex space, emergency evacuation systems are required because of the possibility of casualties when an accident situation occurs. However, because present systems are composed of basic devices, such as alarms, emergency exit signs, and announcement regarding the situation and inform only the least information to evacuees, evacuees are not able to judge objectively. To solve these problems, various evacuation algorithms have been proposed. However, these studies aim to search evacuation routes based on specific risk factors or to model the effects of bottlenecks in evacuation situations. Therefore, there is a limit to apply to real systems. Therefore, we propose algorithms to search the optimal evacuation route considering various risk factors such as fire and bottleneck in evacuation situations and to be applicable in actual situation in this paper. Performance evaluation using computer simulations showed that the proposed scheme is effective.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.1
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• pp.9-16
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• 2018

Predictive control is a very practical method that obtain the current input that minimizes the future errors of the reference command and state by use of the predictive model of the controlled object, and can also consider the constraints of the state and input. Although there have been studies in which predictive control is applied to mobile robots, performance has not been optimized as various control parameters for determining control performance have been arbitrarily specified. In this paper, we apply the genetic algorithm to the trajectory tracking control of a mobile robot with input constraints in order to minimize the trajectory tracking errors through control parameter tuning, and apply the quadratic programming Hildreth method to reflect the input constraints. Through the computer simulation, the superiority of the proposed method is confirmed by comparing with the existing method.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.8
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• pp.1041-1048
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• 2018

Gartner's Hype Cycle model is widely used to describe technology maturity, acceptability, and commercialization. In the Hype Cycle model, the techniques go through five stages, those are Innovation Trigger(first stage), stage Peak of Inflated Expectations(second stage), Trough of Disillusionment(third stage), Slope of Enlightenment(fourth stage) and Plateau of Productivity(fifth stage). In many studies, Hype Cycle is widely used as a basis for future prediction of technology, but the verification is somewhat lacking. In this paper, we analyzed the technologies that appeared in the Hype Cycle for the emerging technologies from 1995 to 2017. Through this, we found technologies that appeared as non first stage when first appearing, and techniques that showed a reversal of the maturity stage. In addition, we found that none of the technologies from 1995 to 2017 had gone through stages 1-5.

• The KIPS Transactions:PartB
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• v.10B no.5
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• pp.503-508
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• 2003

Since surgical treatment of the spine should overcome neurological compromises, the operative procedures need to be carefully planned and carried out with high degree of precision. Percutaneous vertebroplasty is a surgical procedure that was introduced for the treatment of compression fracture of the vertebrae. This procedure includes puncturing vertebrae and filling with polymethylmethacrylate (PMMA). Recent studies have shown that the procedure could provide structural reinforcement for the osteoporotic vertebrae while being minimally invasive and safe with immediate relief of pain. However, failures of treatment due to excessive PMMA volume injection have been reported as one of complications in vertebroplasty. It is believed that the control of PMMA volume is one of the most critical factors that can reduce the incidence of complications. Therefore, clinical success of vertebroplasty can be dependent on the volume of PMMA injection for a given patient. In this study, the optimal volume of PMMA injection for vertebroplasty was predicted based on the image analysis of a given patient.