• Journal for History of Mathematics
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• v.18 no.1
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• pp.49-66
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• 2005

We briefly survey the history of abacus and counting rods which had been most widespread devices for arithmetical calculations. And we explain and compare the methods and principles of calculation on the abacus and counting rods. Only multiplication and division are presented here with examples. In these course we can see that the principles of calculation on the abacus are inherited from that of calculation on the counting rods. We also discuss the educational value of the abacus.

• Journal of the Korean housing association
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• v.23 no.5
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• pp.61-73
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• 2012

This study applied the value of floor-area-ratio standard calculation method to case areas and analyzed them to overcome the limits of previous studies in calculation methods for area standards and land price (value) standard development rights. The results are presented as follows: First, criteria to select sending areas and receiving areas are needed. Second, calculation methods based on the value of floor-area-ratio standard can be widely used as standardized criteria in various areas. Third, for the connection of sending areas with receiving areas, the connections of 1:1, n:1, 1:n, and n:n are available and the location of possible dealing areas should be considered. Also, the choice of connecting unions that meet the purpose of TDR presented by local governments is available. Fourth, for Gwangju, as receiving areas downtown provide higher profits than previous renewal projects, the application of TDR is available. Application methods to overcome problems are presented as follows: First, criteria to select sending and receiving areas should be prepared and implemented in an order of priority. Second, in calculating development rights, methods based on the value of floor-area-ratio standard should be used. Third, the standards and principles of sending and receiving areas should be designated and possible dealing areas should not be limited.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.762-763
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• 2008

The purpose of this paper is to investigate and compare the inductance evaluation methods of interior permanent magnet synchronous motors (IPMSM). Three major finite element methods are discussed. Their detail calculation processes will be presented as well as their fundamental principles. Not only the results, but also their solving method, computation time and complexity also will be compared. Finally, the calculated results will be verified with an experiment.

• International Journal of Computer Science & Network Security
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• v.24 no.4
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• pp.44-50
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• 2024

This paper offers an overview of matrix formation and calculation techniques within the framework of General Linear Models (GLMs). It takes a sequential approach, beginning with a detailed exploration of matrix formation and calculation methods in regression analysis and univariate analysis of variance (ANOVA). Subsequently, it extends the discussion to cover multivariate analysis of variance (MANOVA). The primary objective of this study was to provide a clear and accessible explanation of the underlying matrices that play a crucial role in GLMs. Through linking, essentially different statistical methods, by fundamental principles and algebraic foundations that underpin the GLM estimation. Insights presented here aim to assist researchers, statisticians, and data analysts in enhancing their understanding of GLMs and their practical implementation in diverse research domains. This paper contributes to a better comprehension of the matrix-based techniques that can be extended to GLMs.

• School Mathematics
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• v.11 no.4
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• pp.723-743
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• 2009

This paper analyzed the main contents of multiplication and division of fractions in elementary mathematics textbooks and workbooks aligned to the national mathematics curriculum. This paper first explored the adequacy of when to teach the contents, the connection of instructional flow across grades, and the method of constructing a unit to teach multiplication or division of fractions. This paper then analyzed in detail the contents with regard to the types and frequency of word problems, the types of visual models and frequency, and the process of formalizing the calculation methods and principles. It is expected that the issues and suggestions stemming from this analysis of current textbooks and workbooks are informative in developing new instructional materials aligned to the recently revised mathematics curriculum.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.05a
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• pp.142-145
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• 2008

Process simulation requires accurate and reliable data for a wide variety of material properties, ranging from thermal conductivity to flow stress curves. Traditionally such data are gathered from experimental sources, which has significant disadvantages in that not all of the required data is readily available, it may be from various sources that are themselves inconsistent, measurement of high temperature properties is expensive, and furthermore the properties can be sensitive to microstructure as well as to alloy composition. This article describes the development of a new multi-platform software program called JMatPro, which is based on CALPHAD methodology, for calculating the properties and behavior of multi-component alloys. A feature of the JMatPro is that the calculations are based on sound physical principles rather than purely statistical methods. Thus, many of the shortcomings of methods such as regression analysis can be overcome.

• Journal of The Korean Association of Information Education
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• v.12 no.3
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• pp.303-312
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• 2008

In correspondence to the educational demand on study of computer principles that is recently being focused, this study promotes basic understanding on data structure and algorithm at the elementary student level through the process of simple numerical expressions and proposes effective education contents and methods. For this, an unplugged type computer education material was produced to understand the method of the computers for receiving data through activities. Also, we proposed students to create animation data to learn numerical expressions and algorithm through arrangements and linked lists. To examine educational effectiveness of this study, an experiment study was conducted through the education content and method to the subject of one class in the fifth-grade of elementary school located in OO metropolitan city. As a result, the student learned that there is a difference in calculation method between computers and people; and this enabled basic understanding on algorithm and data structure and presented positive responses to algorithm and data structure. In conclusion, it is confirmed that it is possible to provide effective education for students if the principle study of algorithm is proposed to proper levels.

• Journal of the Korean Magnetics Society
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• v.25 no.4
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• pp.101-105
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• 2015

Recent theoretical calculations predicted that a system composed exclusively of 3d transition metals without 4d/5d transition metals or rare earth metals can have strong perpendicular magnetocrystalline anisotropy (MCA) if Fe and Ni layers are arranged appropriately. They considered only Fe-terminated surfaces, noting that Fe/MgO(001) and CoFeB/MgO(001) show strong perpendicular MCA. In this paper, we investigate magnetism and MCA of Ni/Fe(001) surface where Ni layer is positioned at the surface, by using complementarily the first principles calculational methods of Vienna Ab-initio Simulation Package (VASP) and Full-potential Linearized Augmented Plane Wave (FLAPW) method. Comparing results of magnetism and MCA obtained by VASP with the results by FLAPW method, we find the VASP results do not show big difference from results by FLAPW method. Magnetic moments of Fe and Ni are enhanced due to strong hybridization between Fe and Ni bands. MCA of Ni/Fe(001) is parallel to the surface, which implies the surface termination plays a crucial role in determining MCA of a system.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.58
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• pp.3-33
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• 2013

The purpose of this paper is to examine the problems in exercising buyer's right to claim damages for the breach of contract by the seller in international sales contract and to suggest reasonable counter-measures. The main contents are as follows: First, this author analyzed the principles of the seller's liability for damages in detail and examined the methods for the calculation of damages on the basis of Arts.74~77. As these articles are found to be insufficient in practical application, this author further examined the UNIDROIT Principles(2004) to confirm whether these Principles can fill the gaps of CISG or not, which turned out their gap-filling functions. Second, this author tried to find any expected problems when the buyer resorts to the right to claim damages in case of the seller's breach of contract including the estimation of damages, the burden of proof, causation, the proof of appropriateness for avoidance, the proof of buyer's obligation to mitigate the loss and so on. The reason is that these problems may cause a lot of difficulties in real business. As result, many buyers have given up their reasonable rights to claim damages so far. Finally, from the buyer's perspective, this author would like to suggest a liquidated damage clause(LD Clause) which gives the buyer to received a specified sum in case of seller's non-performance and/or a demand guarantee(or standby L/C) which guarantees buyer to secure unconditional payment independent of the underlying contract. For these purposes, the buyer should try to insert the LD Clause and/or Guarantee Clause in the contract when the buyer and the seller negotiate the sales contract. Also there are a lot of considerations and limitations in using the LD Clause and the Guarantee Clause in their real business, mainly dependent up bargain power between the seller and the buyer, for which this author promise to examine in detail in the future.

• Structural Engineering and Mechanics
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• v.64 no.4
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• pp.413-426
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• 2017

Probabilistic methods are used in engineering where a computational model contains random variables. The proposed method under development: Direct Optimized Probabilistic Calculation (DOProC) is highly efficient in terms of computation time and solution accuracy and is mostly faster than in case of other standard probabilistic methods. The novelty of the DOProC lies in an optimized numerical integration that easily handles both correlated and statistically independent random variables and does not require any simulation or approximation technique. DOProC is demonstrated by a collection of deliberately selected simple examples (i) to illustrate the efficiency of individual optimization levels and (ii) to verify it against other highly regarded probabilistic methods (e.g., Monte Carlo). Efficiency and other benefits of the proposed method are grounded on a comparative case study carried out using both the DOProC and MC techniques. The algorithm has been implemented in mentioned software applications, and has been used effectively several times in solving probabilistic tasks and in probabilistic reliability assessment of structures. The article summarizes the principles of this method and demonstrates its basic possibilities on simple examples. The paper presents unpublished details of probabilistic computations based on this method, including a reliability assessment, which provides the user with the probability of failure affected by statistically dependent input random variables. The study also mentions the potential of the optimization procedures under development, including an analysis of their effectiveness on the example of the reliability assessment of a slender column.