• Journal of The Korean Association For Science Education
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• v.14 no.1
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• pp.85-102
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• 1994

The purpose of this study was to analyze students' physics problem solving processes and to find the patterns of their problem spaces when high school and university students solved the physics problems. A total of 51 students in a high school and in two universities participated in this study. Their thinking processes in solving 5 physics problems on electric circuit were recorded by using 'thinking aloud' method and were transferal into protocols. 'The protocols were analyzed by the coding system of problem solving process. One of the major theoretical contributions of the computer simulation approach to problem solving is the idea of problem space. Such a concept of problem space was applied to physics problems on electric circuit in this study, and students' protocols were analyzed by the basic problem spaces which were made up from the item analysis by the researcher. The results are as follows: 1) On the average 4.0 test items among 5 ones were solved successfully by all subjects, and all of the items were solved correctly by only 19 persons among all of them. 2) In regard to the general steps of problem solving process, there was little difference for each item between the good solvers and the poor ones. But according to the degree of difficulty of task there was a good deal of difference. For a complex problem all of 4 steps were used by most of students, but for a simple one only 3 steps except evaluating step were used by most of them. 3) It was found in this study that most of students used mainly the microscopic approach, that is, a method of applying Ohm's law on electric circuit simply and immediately, not using the properties of electric circuits. And also it was observed that most of students used the soloing tom below, that is, a solving path in which they were the first to calculate physical Quantities of circuit elements, before they caught hold of the meaning of the given problem regardless of the degree of difficulty.

• Journal of The Korean Association For Science Education
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• v.17 no.4
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• pp.525-540
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• 1997

The present study tested the hypothesis that maturation of the prefrontal lobes is a crucial factor determining the performance of scientific reasoning tasks, Functions of the prefrontal lobes, such as activating relevant information, sequential planning and monitoring, and inhibiting irrelevant information, are related thinking patterns with scientific reasoning. Therefore, we inferred the idea that the prefrontal lobes play an important role in scientific reasoning. To test the hypothesis. the present study investigated a prefrontal lobe patient's task solving procedures in scientific reasoning tasks and the correlation and regression analysis between a test of prefrontal lobe function and two scientific reasoning tasks, The perseverative errors in the Wisconsin Card Sorting Test(WCST) was used as a measure of the prefrontal lobe function, The Melinark Type Task and the Classroom Test of Scientific Reasoning were used as measures of scientific reasoning abilities. Ages and Group Embedded Figure Test were also used as measures of two alternative hypotheses, general maturation and field independency respectively. The prefrontal lobe patient showed a crucial deficiency in solving scientific reasoning tasks. In the tasks, the patient could not used the reasoning of If... and... then... therefore pattern. In correlation study, the perseveration errors of the WCST showed a significantly negative correlation with two scientific reasoning tasks. Multiple regression study also showed that the perseveration errors measured as a function of the prefrontal lobes have more contribution to scientific reasoning ability than contributions of alternative hypotheses. Therefore, the present study supported the hypothesis that prefrontal lobes play a crucial role in scientific reasoning ability, What function of the prefrontal lobes do play crucial role in scientific reasoning? The present study provided an explanation for the question, which inhibiting ability of the prefrontal lobes is responsible for the scientific reasoning ability, in a part at least. That is, perseverative tendency in task-solving procedures causes a deficiency of an ability to inhibit the wrong information to solve a task. The present study provided a possibility of neuropsychological approach in science education research. The present study also showed an importance of the prefrontal lobe development in the performance of scientific reasoning task.

• International Journal of Fluid Machinery and Systems
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• v.8 no.4
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• pp.264-273
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• 2015

This presentation describes an experimental approach for the detection of cavitation in hydraulic machines by use of ultrasonic signal analysis. Instead of using the high frequency pulses (typically 1MHz) only for transit time measurement different other signal characteristics are extracted from the individual signals and its correlation function with reference signals in order to gain knowledge of the water conditions. As the pulse repetition rate is high (typically 100Hz), statistical parameters can be extracted of the signals. The idea is to find patterns in the parameters by a classifier that can distinguish between the different water states. This classification scheme has been applied to different cavitation sections: a sphere in a water flow in circular tube at the HSLU in Lucerne, a NACA profile in a cavitation tunnel and two Francis model test turbines all at LMH in Lausanne. From the signal raw data several statistical parameters in the time and frequency domain as well as from the correlation function with reference signals have been determined. As classifiers two methods were used: neural feed forward networks and decision trees. For both classification methods realizations with lowest complexity as possible are of special interest. It is shown that two to three signal characteristics, two from the signal itself and one from the correlation function are in many cases sufficient for the detection capability. The final goal is to combine these results with operating point, vibration, acoustic emission and dynamic pressure information such that a distinction between dangerous and not dangerous cavitation is possible.

• Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.227-231
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• 1998

The teleosts represent ancient real-bony vertebrates in phylogeny and resemble major genetic patterns to higher vertebrates. In the present study, we have defined the single family of insulin-like growth factors (IGFs) from flounder (Paralichthys olivaceus), compared to the prototype of IGFs observed in the Agnathan hagfish. In flounder, IGFs are clearly diverged into two major types including type I and II, and they are structurally similar by displaying a multidomain structure consisting of five functional regions as previously found in other vertebrates. However, flIGF-I appears to be more basic (pI 8.03) than the flIGF-II (pI 5.34) in the fully processed form for the B to D domain region. The flIGF-I seems to contain an evolutionary conserved Asn-linked glycosylation in E domain, which is not found in flIGF­II. The most interesting feature is that flIGF-II appeared to be structurally close to hagfish IGF in secondary structures, particularly in Band D domains. This could tell us an idea on the molecular divergence of IGFs from the Agnatha to teleosts during the vertebrate phylogeny. It also support, in part, a notion regarding on how IGF-II is appeared as more embryonic during development. Nonetheless, the biologically active B to D domain region of flIGF-II shows significant sequence homology of $65.6\%$ to flIGF-Is and contains the evolutionary conserved insulin-family signature, as well as a reserved recognition site (Lys) in D domain, necessary to generate proteolytic cleavage for E-peptide. A significant structural difference was found in E domain in which flIGF-I possesses two potential alternative splicing donor site at $Val^{17,\;24}$ of E domain. Therefore, it seems so far that IGF-I sorely produces spliced variants due to the spliced E-peptide moiety while IGF-II appears to be maintained in a single type during evolution. IGF-II, however, may be also possible to transcribe unidentified variants, depending on the physiological conditions of tissues in vertebrates in vivo.

• The Journal of Korea Robotics Society
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• v.7 no.3
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• pp.182-193
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• 2012

This paper presents a new behavior planning scheme for autonomous robots, allowing them to handle various objects used in our daily lives. The key idea underlying the proposed scheme is to use affordance concepts that provide a robot with action possibilities triggered by a relation between the robot and objects around it. Specifically, the robot attempts to find the affordances and to determine the most adequate action among them. Through a series of the perception processes, robot motions can be planned and performed to complete assigned tasks. What is of particular importance from the practical point of view is a decision making capability to determine the best choice by comparing the human's body characteristics and behavioral patterns as criteria with action possibilities as alternatives. For this, the analytic hierarchy process (AHP) technique is employed to systematically evaluate the correlation between the criteria and the alternatives. Moreover, the alternatives arranged in order of priority through the decision making process enable the robot to have redundant solutions for the assigned task, resulting in flexible motion generation. The effectiveness and validity of the proposed scheme are verified by performing extensive simulations using objects of our daily use.

• Research in Community and Public Health Nursing
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• v.7 no.1
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• pp.38-51
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• 1996

There is a increasingly growing emphasis on health promotion, disease prevention and optimum functioning for peaple including the chronically ill and disabled. According as the purpose of the nursing is the promotion of health, the value and belief of heal th within the nursing paradigm need to be defined in every culture. The paradigm components must be explored for meaning given by the aged in their traditional thought and philosophy, The problem addressed by this qualitative study was how the aged recognize value and belief of health, which contribute to the development of Korean nursing theory. Theoretical support for the study was from Leininger's cultural care theory and Korean philosophy and traditional oriented thought. Literature review refers to literature on the aged, health of the aged, and definition and meaning of general health concept. Grounded theory methodology guied the research methodology and analysis to build a substantive theory. The informants were 119 from a variety of social levels and family patterns; traditionally the aged are responsible for the health. The concentrated interviewing period was from may to june, 1995 ; the interviews were done by the researcher with two supporter and most were recorded on audio tape. Result from analysis of base datas follows; The value and belief of health that emerged from the categories and properties were the physical stability, the stability of mind, the stability of mind and body, the smoothness (harmony) of body function, the family concord, and the perfection of self. These values and beliefs of health are affected by the cosmic dual forces thought is based on the Great Absolute, family principle of confucian scholar, and Buddism. Among the values and beliefs of health, family concord is found out Korean culture peculiarities. These values and beliefs are all integrated into the idea of health. The study provided implications for nursing theory research, education, and practice change and development.

• Transactions on Electrical and Electronic Materials
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• v.7 no.6
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• pp.313-318
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• 2006

This paper introduces a partial discharge (PD) severity metric, S, based on the evaluation of time-sequence PD data capture and resulting Time-Sequence-Analysis Discharge (TSAD) level distributions. Basically based on an IEC60270 measurement technique, each PD event is time stamped and the discharge level noted. By evaluating the time differences between a previous and subsequent discharge, a 3D plot of time-sequence activity and discharge levels can be produced. From these parameters a measurement of severity, which takes into account dynamic or instantaneous variations in both the time of occurrence and the level of discharge, rather than using standard repetition rate techniques, can be formulated. The idea is to provide a measure of the severity of PD activity for potentially measuring the state of insulation within an item of plant. This severity measure is evaluated for a simple point-plane geometry in $SF_{6}$ as a function of gap distance and applied high voltage. The results show that as the partial discharge activity increases, the severity measure also increases. The importance of future investigations, quantifications and evaluations of the robustness, sensitivity and importance of such a severity measurement, as well as comparing it with typical repetition rate assessment techniques, and other monitoring techniques, are also very briefly discussed.

• Journal of the Korean Solar Energy Society
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• v.33 no.5
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• pp.51-59
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• 2013

It is usual to evaluate the performance of the cool roof by measuring in-site rooftop temperature using thermal infra-red camera. The principal advantage of rooftop thermal infrared image acquired in oblique vantage point of super high-rise building as a remote sensor is to provide, in a cost-effective manner, area-wide information required for a scattered rooftop target with different colors, utilizing wide view angle and multi-temporal data coverage. This research idea was formulated by incorporating the concept of traditional remote sensing into rooftop temperature monitoring. Correlations between infrared image of super high-rise building and in-situ data were investigated to compare rooftop surface temperature for a total of four different rooftop locations. The results of the correlations analyses indicate that the rooftop surface temperature by the infrared images of super high-rise building alone could be explained yielding $R^2$ values of 0.951. The visible permanent record of the oblique thermal infra-red image was quite useful in better understanding the nature and extent of rooftop color that occurs in sampling points. This thermal infrared image acquired in oblique vantage point of super high-rise made it possible to identify area wide patterns of rooftop temperature change subject to many different colors, which cannot be acquired by traditional in-site field sampling. The infrared image of super high-rise building breaks down the usual concept of field sampling established as a conventional cool roof performance evaluation technique.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.4
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• pp.91-97
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• 2011

In this paper we present an approach to the structure identification based on genetic algorithm and to the parameter identification by hybrid learning method in neuro-fuzzy-genetic hybrid system in order to predicate the Mackey-Glass Chaotic time series. In this scheme the basic idea consists of two steps. One is the construction of a fuzzy rule base for the partitioned input space via genetic algorithm, the other is the corresponding parameters of the fuzzy control rules adapted by the backpropagation algorithm. In an attempt to test the performance the proposed system, three patterns, x(t-3), x(t-6) and x(t-9), was prepared according to time interval. It was through lots of simulation proved that the initial small error of learning owed to the good structural identification via genetic algorithm. The performance was showed in Table 2.

• Journal of Korean Elementary Science Education
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• v.22 no.2
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• pp.138-148
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• 2003

This study was to analyze how elementary school science textbooks explain dissolution and to examine the patterns of elementary school teachers' conceptions on dissolution and the teaching practices on dissolution of elementary school teachers. According to the result of the textbook analysis, the textbooks based on the 7th curriculum didn't explain dissolution very differently from those based on the 6th curriculum. The contents dealing with dissolution in the textbooks of 7th curriculum became difficult gradually as the year went up, but the connected organization of the contents made students learn it easily. For example, in order to learn dissolution introduced first in the 3rd year 2nd semester textbook, students would tell soluble substance in water from insoluble substance in water as they put powdered substance in water. In the 5th year 1st semester textbook students were supposed to acquire the knowledge related to dissolution through the designed activities such as comparing solubility produced by different solvents and defining a solvent, a solute, dissolution, and a solution. In addition, teachers' guide for 5th year 1st semester textbook elucidated the principle of dissolution using attraction concept that was scientific. The result of the survey on teachers showed that 90% of elementary school teachers understood the dissolution of salt in water just as millet particles' filling the space between bean particles and they responded that they demonstrated millet particles' filling the space between been particles when they taught the dissolution of salt in water. When it comes to teachers who had the right idea on dissolution as the attraction conception, understanding was one thing and teaching was another, because they often instructed dissolution as the space conception in the real teaching.