• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.6A
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• pp.1001-1011
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• 2006

It is a general agreement that exact statistical solutions can be found by a Monte Carlo technique. Due to difficulties, however, in the numerical generation of random fields, which satisfy not only the probabilistic distribution but the spectral characteristics as well, it is recognized as relatively difficult to find an exact response variability of a structural response. In this study, recognizing that the random field assumes a constant over the domain under consideration when the correlation distance tends to infinity, a semi-theoretical solution of response variability is proposed for general structures. In this procedure, the probability density function is directly used. It is particularly noteworthy that the proposed methodology provides response variability for virtually any type of probability density function, and has capability of considering correlations between multiple random variables.

• Journal of the Korean School Mathematics Society
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• v.20 no.3
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• pp.277-302
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• 2017

Educational objectives for mathematics in the curriculum revised in 2009 and the curriculum revised in 2015 put great emphasis on practical use of math, but perception of that lacks at schools. Accordingly, this research is recognizing the need for paying attention to curriculum focusing on mathematical connectivity and is inspecting CMP curriculum which has been developed over the years to reinforce problem solving competence and improve communication skills. This study analyzes CMP textbooks published as third edition in 2014 after several revisions, focusing on equations, inequalities and functions. First, this thesis analyzes mathematical connectivity using a new analysis framework which applied the modes of representation(situations, verbal description/ tables/ graphs/ formulae) made by Janvier(1987). Second, this research analyzes connectivities between different units, various sections, other subjects and practical contents related to the real life. The results: CMP textbooks use various practical materials for specific situations. They represent twelve processes of connectivity according to the modes of representation of Janvier. The books also show relationship between equations and functions, between inequalities and functions. And CMP textbooks include other subjects and practical contents.

• Proceedings of the Korea Information Processing Society Conference
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• 2003.05a
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• pp.367-370
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• 2003

과학자나 공학자들은 빛이나 소리와 같이 주기적인 특성을 갖는 현상을 연구하는 경우가 많다. Fourier 변환은 이러한 주기함수의 근사 함수를 구할 때 유용하게 이용되고 있다. 본 논문에서는 극좌표 표현되는 함수의 근사 함수를 구하는 문제를 다룬다 일반적으로 컴퓨터 상에 구현하기 위해서는 이산형 Fourier 급수전개를 이용하는데 지금까지는 근사 함수를 컴퓨터 상에서 구할 때 이산화 표본수를 경험에 의해 임의로 결정하여 이용하였으나 본 연구에서는 Fourier 변환의 성질을 이용하여 주어진 함수에 따라 필요한 이산화 표본 수를 자동적으로 결정하는 알고리즘을 제안한다.

• Economic and Environmental Geology
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• v.49 no.4
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• pp.269-280
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• 2016

I presented three vector crustal magnetic anomaly components and six gradients by using spherical Slepian functions over the cap area of $20^{\circ}$ of radius centered on the South Pole. The Swarm mission, launched by European Space Agency(ESA) in November of 2013, was planned to put three satellites into the low-Earth orbits, two in parallel in East-West direction and one in cross-over of the higher altitude. This orbit configuration will make the gradient measurements possible in North-South direction, vertical direction, as well as E-W direction. The gravity satellites, such as GRACE and GOCE, have already implemented their gradient measurements for recovering the accurate gravity of the Earth and its temporal variation due to mass changes on the subsurface. However, the magnetic gradients have little been applied since Swarm launched. A localized magnetic modeling method is useful in taking an account for a region where data availability was limited or of interest was special. In particular, computation to get the localized solutions is much more efficient and it has an advantage of presenting high frequency anomaly features with numbers of solutions fewer than the global ones. Besides, these localized basis functions that were done by a linear transformation of the spherical harmonic functions, are orthogonal so that they can be used for power spectrum analysis by transforming the global spherical harmonic coefficients. I anticipate in scientific and technical progress in the localized modeling with the gradient measurements from Swarm and here will do discussion on the results of the localized solution to represent the three vector and six gradient anomalies over the Antarctic area from the synthetic data derived from a global solution of the spherical harmonics for the crustal magnetic anomalies of Swarm measurements.

• Journal of the Korea Society of Computer and Information
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• v.3 no.1
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• pp.25-34
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• 1998

There are two major method for expressing parallelim in functional languages. The one is the strictness analysis and the other the annotation. The strictness analysis is a method that a compiler detects parallelism and expresses the detected information in the object program. The annotation is a method that a programmer detects parallelism and expresses in the source program. This study is on the annotation and is aimed at construction of a translator for a functional language which has an annotation syntax. The translator translates a source program to enriched lambda-calculus graphs. The translator is implemented in C using compiler development tools such as YACC and Lex, under UNIX environments. In this paper we present the design and implementation techniques for developing the front-end of the translator.

• Journal of the Korean Institute of Telematics and Electronics
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• v.21 no.4
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• pp.43-51
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• 1984

In the case of Quine Mccluskey's methode for Boolean function minimization, we have to examine each bits of binary represented minterms. In this paper, cube relations between misterms that are represented by means of decimal number, and all sorts of rules for Boolean function minimization are described as theorems, and they are verified. And based on these theorems, the new fast algorithm for Boolean function minimization is proposed. An example of manual operation is sholvn, and the process is writed out by a FORTRAN program. In this program, the essential pl.imp implicants of the Boolean function that has 100 each of minterms including redundant minterms, are finked and printed out, (the more minterms can be treated if we take the more larger size of arrays) and the outputs are coincided with the results of manual operation.

• Education of Primary School Mathematics
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• v.20 no.1
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• pp.53-68
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• 2017

Although the table, as one of the representations for helping mathematics understanding, steadily has been shown in the mathematics textbooks, there have been little studies that focus on the table and analyze how the table may be used in understanding students' functional thinking. This study investigated the elementary school 5th graders' abilities to design function tables. The results showed that about 75% of the students were able to create tables for themselves, which shaped horizontal and included information only from the problem contexts. And the students had more difficulties in solving geometric growing pattern problems than story problems. Building on these results, this paper is expected to provide implications of instructional directions of how to use the table as 'function table'.

• Journal of the Korean Geographical Society
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• v.38 no.6
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• pp.949-960
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• 2003

The marginal implicit price of air quality can be measured by taking a partial derivative of hedonic price function (HPF) with respect to the level of air quality. It has been pointed out that the size of the marginal implicit price varies with the use of different function forms, different estimation methods, and the different ways of measuring air quality level in estimating HPF. In addition to these factors, this study shows theoretically and empirically the way housing properties are represented on a digital map could differentiate the size of marginal implicit price of air quality when GIS is used to measure location attributes of the housing properties in the Korean apartment market. Furthermore, this study shows that the degree of difference in the marginal implicit price due to the manner in which housing properties are represented on a digital map can be larger than the degree of difference in the marginal implicit price due to using different function forms and estimation methods. The major implication from the results of this study is that one should carefully try diverse ways of representing housing properties in the Korean apartment market on a digital map in the process of estimating HPF, as he or she usually tries diverse function forms and estimation methods, to see if the value of the marginal implicit price of air quality varies substantially.

• Review of KIISC
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• v.2 no.4
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• pp.104-109
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• 1992

스위치 이론이나 디지탈 공학$^{2)}$, 정보보호학$^{6.8)}$등의 분야에서 자주 사용되는 많은 함수들은 유한체 GF$(q)^n$에서 GF(q)의 값을 취하는 함수들이다. 특히 q=2인 경우에 함수 f는 쉽게 진리표에 의해 표현된다. 본 글에서는 유한체 위에서 성립하는 행렬 구조를 갖는 대수적 표준형식 변환에 대하여 알아보고, 변환의 계산을 점화적으로 이행해보며, 난수함수의 복잡도에 관한 확률분포를 살펴본다. 대수적 표준형식은 함수의 비선형 위수나 복잡도에 관한 판단에 유용하게 응용할 수 있다.

• Journal of Ocean Engineering and Technology
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• v.13 no.1 s.31
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• pp.39-50
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• 1999

특이 가중함수로 표현된 shepard interpolant와 일관조건을 사용하여 무요소법 형성함수를 도출하였다. 따라서 통상의 EFGM(Element Free Galerkin Method)과는 달리 변위로 주어지는 경계조건을 자연스럽게 부과할 수 있다. 수치계산 예로서 외팔보 문제를 다루었는데 보이론과 비교하여 매우 잘 맞는 결과를 보여주고, 유한요소법과의 결합도 자연스럽게 이루어짐을 보인다. 또 penny-shaped 균열을 다루는데, 응력확대계수는 균열 표면의 변위로부처 직접 계산하여 해석해와 비교한다.