• Journal of The Korean Association For Science Education
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• v.17 no.1
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• pp.75-83
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• 1997

The purpose of this study was to determine the strategies that middle school students used in solving problems concerning density and solubility. These were compared in the aspects of problem contexts for 42 students of varying logical reasoning ability, spatial ability, and learning approach. A coding scheme used consists of five categories: reading & organization, production, errors, evaluation, and strategy. Students' protocols were analyzed after intercoder agreement had been established to be .95. The results were as follows: 1. Students had more difficulties in reading and organizing the problems in everyday contexts than in scientific contexts. Students at the concrete-operational stage and / or surface approach were more likely to have difficulties in reading and organizing the problems than those at the formal-operational stage and / or deep approach. 2. Students tended to split up the solubility problems into sub-problems and to solve the density problem in everyday contexts in random manner. These were significantly correlated with the test scores concerning logical reasoning ability, spatial ability, and learning approach at the .1 level of significance. 3. Major errors in solving the density problems were to disregard the given information or generated and to use inappropriate information. Many errors in solving the solubility problems were found to be executive errors. The strategy to use the information given appropriately was positively related to students' logical reasoning ability, spatial ability, and learning approach. 4. More evaluation strategies were found in everyday contexts. Their strategies to grasp the meaning of answers and to check the math were significantly related to students' logical reasoning ability. 5. Students used the random trial-and-error strategy more than the systematic strategy and the systematic trial-and-error strategy, especially in everyday contexts. The strategies used by the students were significantly related to students' logical reasoning ability, spatial ability, and learning approach.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.18 no.2
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• pp.145-153
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• 2007

Objectives: This study was focused on the influence of chronic aircraft noise exposure on children's continuous performance, intelligence and reading skill. Methods: We enrolled 586 children in 4-6th grade of 7 primary schools near air base in Korea. Continuous performance was measured using the computerized ADS program. We analyzed 477-512 children on the visual continuous performance test, auditory continuous performance test, intelligence test, and reading and the vocabulary test. Intelligence was measured using vocabulary, digit span, block design, and digit symbol tests of K-WISC-III. Results: The commission error and variability deviation of auditory continuous performance test and reading test were significantly higher among children in schools with the helicopter noise and the fighting plane noise compared to children in the low noised schools. Conclusion: There was a possibility that chronic aircraft noise exposure was associated with impairment of the school performance. The result of our study also shows chronic aircraft noise was associated with reading ability.

• Journal of the Ergonomics Society of Korea
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• v.7 no.2
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• pp.31-44
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• 1988

If an error occurs in the automatic mode when the advanced teleoperator system performs a task in hostile environment then the automatic mode changes into the manual mode. The operation by the control program and the operation by a human recover the error in the manual mode. The system resumes the automatic mode and continues the given task. It is necessary to improve the manual mode in order to make the best use of a man-robot system, as a part of the human interface technique. Therefore, the error recovery task is performed by combining the operation by the control program representing autonomy of a robot and the operation by a human representing versatility of a human operator effectively in the view point of human factors engineering. The geometric inverse kinematics is used for the calculation of the robot joint values in the operation by the control program. The singularity operation error and the parameter operation error often occur in this procedure. These two operation errors increase the movement time of the robot and the coordinate reading time, during the error recovery task. A singularity algorithm, parameter algorithm and fuzzy control are studied so as to remove the disadvantages of geometric inverse kinematics. And the geometric straight line motion is studied so as to improve the disadvantages of the operation by a human.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.7
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• pp.101-106
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• 2004

Measurements of linear motion accuracy for one axis of NC lathe have achieved with laser interferometer system, but measurement of plane motion accuracy for two axes on zx-plane of NC lathe have not achieved with the above system. Therefore in this study, measuring unit system is organized using two optical linear scales in order to acquire error. data during of plane motion of ATC(Automatic Tool Change.) of NC lathe by reading zx-plane coordinates. Two optical linear scales of measuring unit are fixed on zx-plane of NC lathe, and moving part of the scales are fixed to the ATC and then error motion data of z, x-coordinates of the ATC are received from the scales through the PC counter card inserted in computer at constant time intervals using tick pulses coming out from computer. And then, error motion data files acquired from measuring are saved in computer memory and the aspect of plane motion are modeled to plots, and range of the error data, means. average deviations, and standard deviations etc. are calculated by means of statistical treatments using computer programs.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39A no.2
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• pp.86-91
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• 2014

Holographic data storage (HDS) has a number of advantages, including a high transmission rate through the use of a charge coupled device array for reading two-dimensional (2D) pixel image data, and a high density capacity. HDS also has disadvantages, including 2d intersymbol interference by neighboring pixels and interpage interference by multiple pages stored in the same holographic volume. These problems can be eliminated by modulation codes. We propose a 7/9 error-correcting modulation code that exploits a Viterbi-trellis algorithm and has a code rate larger (about 0.778) than that of the conventional 6/8 balanced modulation code. We show improved performance of the bit error rate with the proposed scheme compared to that of the simple 7/9 code without the trellis scheme and the 6/8 balanced modulation code.

• Journal of Yeungnam Medical Science
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• v.27 no.1
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• pp.8-17
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• 2010

It is important to select appropriate antimicrobials for the treatment of infection according to the results of antimicrobial susceptibility tests (ASTs), yet the clinical isolates are sometimes susceptible to antibiotics that are clinically ineffective or this is due to technical error of the ASTs. So, interpretive reading of ASTs is needed and especially for the ${\beta}$-lactams for treating $Enterobacteriacae$. This review describes the interpretive reading of ASTs according to natural antimicrobial resistance and the mechanisms of mechanisms, with giving special attention to the antibiotics phenotypes for $Enterobacteriacae$. Further, as all the diffent tissues have a different antimicrobial concentration for identical antimicrobials, more information is needed on the antimicrobial tissue distribution for the appropriate treatment of infection. (ED note: I hope you send me the paper.)

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.11
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• pp.2269-2274
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• 2009

Customer clustering method is used to make a TDLP (typical daily load profile) to estimate the quater hourly load profile of non-AMR (Automatic Meter Reading) customer. In this paper, repeated small-sized clustering method is supposed to improve the classifying ability of TDLP. K-means algorithm is well-known clustering technology of data mining. To reduce the local maxima of k-means algorithm, proposed method clusters average load profiles to small-sized clusters and selects the highest error rated cluster and clusters this to small-sized clusters repeatedly to minimize the local maxima.

• Transactions of the Society of Information Storage Systems
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• v.7 no.1
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• pp.1-6
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• 2011

A control method for the angle servo of reference beam during reading recoded data images of a holographic data storage system is presented. The recording scheme with angle offset is adopted in order to verify the proposed angle servo. Using this recording scheme, the angle error signal is generated and we can implement the angle servo. Experiments have been performed on recording and reading data images to compensate Bragg angle mismatch.

• Journal of Advanced Navigation Technology
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• v.11 no.4
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• pp.423-429
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• 2007

Since the wireless smart card has played a main role in the identification security application for the building access; this research has its purpose to improve the performance of the smart card system and aims to offer more convenient to user. The contactless cards do not require insertion into a card reader and can work up to centimeters away from the reading device. To be able to cope with this performance the controlling of power consumption through the adaptive modulation and error control is needed. This paper addresses a forward error control (FEC) scheme with the adaptive Reed-Solomon code rate and an M-ary frequency shift keying (M-FSK) modulation scheme with the varying symbol size M over the link. The result of comparing energy efficiencies of adaptive error correction and adaptive modulation to other various static schemes shows to save over 50% of the energy consumption.

• Transactions of the Korean Society of Automotive Engineers
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• v.23 no.6
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• pp.615-622
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• 2015

Recently Digital-TachoGraph(DTG) was mounted mandatorily in commercial vehicles(Taxi, Bus, etc.). DTG records accurate and detailed information of the running state of vehicles related to traffic accident, such as Time, Distance, Velocity, RPM, Brake ON/OFF, GPS, Azimuth, Acceleration. Thus those standardized data can play an important role in traffic accident investigation and reconstruction. To develope the accurate and objective method using the DTG data for the reconstruction of traffic accident, we had conducted several tests such as driving test, high speed circuit test, braking test, slalom test at Korea Automobile Testing & Research Institute(KATRI), and collision test at Korea Automobile insurance repair Research and Training center(KART) with the vehicle equipped with several DTG. Development of the program which enables the reading and analysis of the DTG data was followed. In the experiments, we have found velocity error, RPM error, brake signal error and azimuth error in several products, and also non-continuous event data. The cause of these errors was deduced to be related to the correction factor, the durability of electronic parts and the algorithm.