• Education of Primary School Mathematics
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• v.19 no.1
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• pp.31-45
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• 2016

In this study, the case of error became the object of learning, and the investigator applied these cases to an actual class and established three study problems in order to achieve the purpose of this study. The results of analysis of students' errors in figure based on before achievement test are shown as follows: First, the most errors occurred in the figure was the ones from deficient mastery of prerequisite concepts and definitions. Specially, the errors from deficient mastery of prerequisite concepts and definitions have the majority. it is very high ratio even if it considers an influence of an evaluation question item. so, I think it is necessary to teach concept related figure above all. Second, as the results of application 'finding errors' to a class, there is a meaningful difference in the mathematical achievement and reasoning ability within significance level 5%. This means 'finding errors' is one of the teaching method that it develops the mathematical achievement and reasoning ability.

• Proceedings of the IEEK Conference
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• 1999.11a
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• pp.27-30
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• 1999

A spatio-temporal vector channel model is introduced for the position location (PL) estimation problem for CDMA cellular system environment. Two common ways for the PL make use of the AOA (Angle Of Arrival) and TDOA (Time Difference Of Arrival) from a subscriber to the multiple sensors (base stations). In this paper, we applied the derived vector channel to simulate the multipath channel for the angle of the signal arrival in CDMA systems. Cross-correlation method is a good candidate among other direction finding algorithms available in literature, especially in wideband modulation as in the CDMA system. The PL estimation errors are evaluated for different channels, which are obtained as a parameter of scattering radius of the suggested model. We noted that the number of sensors (base-stations) are related to the PL errors in favor of the available data.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.593-597
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• 1996

This paper describes a method for drawing check of dimension errors, such as deficiency and redundancy of dimensions, input-errors in dimension figures and symbols, etc. The logic for finding dimensional errors is written by using the Turbo C language. Checking for deficiency and redundancy of global dimensions has been performed applying Graph Theory. Especialy, this paper gives an account of checking method for annular parts.

• English Language & Literature Teaching
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• v.12 no.2
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• pp.19-40
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• 2006

This paper deals with a part-specific analysis of grammatical errors in the production of the English passive in writing. The purpose of the study is dual: to explore common error types in forming the passive; and to provide plausible sources of the errors, with special attention to the role of the native language. To this end, this study obtained a large amount of data from Korean EFL university students using an essay writing task. The results show that in forming the passive sentence, errors were made in various ways and that the most common problem was the formation of the be-auxiliary, in particular, the proper use of tense and S-V agreement. Another important finding was that the global errors found in this study were not necessarily those with the greatest frequency. Also corroborated was the general claim that many factors work together to account for errors. In many cases, interlingual and intralingual factors were shown to interact with each other to explain the passive errors made by Korean students. On the basis of the results, suggestions are made for effective and well-formed use of the passive sentence.

• Korean Journal of Computational Design and Engineering
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• v.1 no.2
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• pp.97-106
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• 1996

Existing CAD systems do not provide advanced functions for automatic checking design and drafting errors in mechanical drawings. If the knowledge of checking in mechanical ddrsfting can be implemented into computers, CAD systems could automatically check for design and drafting errors. This paper describes a method for systematic checking of dimension errors. such as deficiency and/or redundancy of dimension input-errors in dimension figures and symbols, etc. The logic for finding dimensional errors is written by using a proccedural language. A geometric model and a topological-graph model are used in this method. Checking for deficiency and redundancy of dimensions is based upon graph Theory.

• Journal of the Korea Institute of Military Science and Technology
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• v.19 no.6
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• pp.681-689
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• 2016

In the direction and location finding field of application, AOA, TDOA and FDOA, etc. are used to improve the performance of geolocation. But, these methods cause some limitations such as the calibrations for phase and amplitude matching and precise time synchronization among receiving channels. In this paper, We suggest a method for generating FDOA using rotating antenna and the geolocation of stationary emitter using two receivers in one platform for minimizing the limitations. We present performance of simulation results and test results of the FDOA geolocation system. The direction finding errors of the system are less than $0.1^{\circ}$ rms and the distance errors are less than 3 % compared with the practical distance.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.6
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• pp.259-265
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• 2000

The purpose of this paper is to detect and identify topological errors in order to maintain a reliable database for the state estimator. In this paper, a two stage estimation procedure is used to identify the topology errors. At the first stage, the WSAV state estimator which has characteristics to remove bad data during the estimation procedure is run for finding out the suspected branches at which topology errors take place. The resulting residuals are normalized and the measurements with significant normalized residuals are selected. A set of suspected branches is formed based on these selected measurements; if the selected measurement is a line flow, the corresponding branch is suspected; if it is an injection, then all the branches connecting the injection bus to its immediate neighbors are suspected. A new WLAV state estimator adding the branch flow errors in the state vector is developed to identify the branch topology errors. Sample cases of single topology error and topology error with a measurement error are applied to IEEE 14 bus test system.

• Korean Journal of Mathematics
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• v.24 no.2
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• pp.181-198
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• 2016

In this work, we suggest a new system of generalized nonlinear regularized nonconvex variational inequalities in a real Hilbert space and establish an equivalence relation between this system and fixed point problems. By using the equivalence relation we suggest a new perturbed projection iterative algorithms with mixed errors for finding a solution set of system of generalized nonlinear regularized nonconvex variational inequalities.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.4
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• pp.8-14
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• 2008

This paper aims at finding out dominant robot configurations with maximal position errors, which can be attributed to the parameter errors, by using Monte-Carlo simulation for error analysis of a 3-axis SCARA(Selective Compliance Assembly Robot Arm) type robot. In particular, the Monte-Carlo simulation is used for virtually measuring on the position errors, instead of physical measurement. In order to measure the observability of the model parameters with respect to a set of robot configurations, we propose the observability index which is defined as the product of singular values for error propagation matrices. Thus the index can be used for discriminating dominant robot configurations from a set of simulated ones in conjunction with standard deviation of positional errors, This paper analyzed error by robot positional error.

• The Journal of the Korean dental association
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• v.54 no.9
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• pp.712-728
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• 2016

These days, the clinical course of dental imaging sector has done a lot of implant-related imaging courses, including cone beam CT. In contrast, the general image reading course is not given a lot of opportunities to learn. Therefore, it is imperative that we talk about the general image interpretation that can be read easily applied in a dental clinic. When we see a strange radiographic finding of our patient in the dental clinic, we should first check whether the radiographic finding is a normal finding or a morbidity. If the finding is diagnosed as a morbidity, you should make plans for the appropriate therapy. The most important step is classification between normal state and morbidity. Some lesions may occur without any clinical symptoms. Therefore, we should read all the parts of radiographs, even the patient does not have clinical symptoms.