• School Mathematics
• /
• v.5 no.3
• /
• pp.385-399
• /
• 2003

In our present elementary mathematics curriculum, natural numbers are taught by using the a method of one-to-one correspondence or counting operation which are not related to measurement, and fractional numbers are taught by using a method which is partially related to measurement. The most serious limitation of these teaching methods is that natural numbers and fractional numbers are separated. To overcome this limitation, Dewey and Davydov insisted that the natural number and the fractional number should be taught by measurement of quantity. In this article, we suggested a method of teaching the natural number and the fractional number by measurement of quantity based on the claims of Dewey and Davydov, and compare it with our current method. In conclusion, we drew some educational implications of teaching the natural number and the fractional number by measurement of quantity as follows. First, the concepts of the natural number and the fractional number evolve from measurement of quantity. Second, the process of transition from the natural number to the fractional number became to continuous. Third, the natural number, the fractional number, and their lower categories are closely related.

• Journal of Korea Technology Innovation Society
• /
• v.7 no.2
• /
• pp.459-479
• /
• 2004

As the high-speed internet access market steadily nears its maturity phase, growth is quickly tapering off and competition, intensifying. As a result telecommunications companies are at present faced with the urgent need to evolve away from a growth model based on continuous acquisition of new subscribers. The recent convergence of telecommunication and broadcasting has come about precisely at this transitional period in the telecommunications market, and is perceived by the industry both as a new business opportunity and as a threat. TV-based VOD(Video on Demand), for one, is able to attract new customers desiring multimedia services of superior quality and to lock-in existing customers. Meanwhile, the latest evolution in network development is brightening the market prospect for TV-based VOD. The service has now hit the market, deployed over VDSL networks - a next-generation high-speed internet - and advanced cable modem networks, delivering high-definition DVD-quality videos. TV-based VOD is a service whose deployment is closely linked to the evolution of subscriber networks. According to the forecast produced by the present study, based on the forecast on the post-ADSL market and a survey conducted on VOD, as post-ADSL subscribers increase from 1.53 million in 2003 to 4.44 million in 2004, and 9.87 million in 2006, the percentage of post-ADSL subscribers with intention to also subscribe to a VOD service is expected to rise from 16% to 34% in 2006. Accordingly, VOD subscribers are estimated to increase from 0.24 million in 2003 to 0.98 million in 2004 and to 3.35 million in 2006.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.10 no.7
• /
• pp.1740-1749
• /
• 2009

As mobile devices evolve and digital convergence trend is here to stay, mobile phones are built with multiple functions including cameras, MP3s, TVs and game consoles. As a consequence, such multi-functional mobile phones come to spend more power, facilitating development of next-generation ultra-capacity lithium ion battery. In addition, environmental regulations and rising oil prices cause demand for hybrid cars to keep rising. Accordingly, more and more attention is being paid to medium and large batteries and more efforts are being made to realize lower battery prices, higher outputs and stability. This study presented a patent technology related to the lithium ion battery packing that allows reducing processes related, increasing productivity and recycling parts other than the body. The lithium ion battery pack to which protection circuits are elastically attached provides short circuit protection for the circuit and the body and makes electric connection of the circuit and the body easier.

• KIPS Transactions on Software and Data Engineering
• /
• v.2 no.4
• /
• pp.291-302
• /
• 2013

Signage can be defined as the media device that provides specific information to many unspecified users in public places. Recently applied context-aware technology, signage provides personal on-demand information services in a way that can continue to evolve. The purpose of this study is to analyze characteristics of types which users identify signage on the perceptions and attitudes about consideration of the perspective of the experts in the fields. The research is carried out by applying Q methodology with in-depth interview. First, interviews are conducted to determine the perceptions and attitudes of experts and practitioners on signage. Thereafter users' perceptions and attitudes toward signage are classified by each types using Q methodology. The first type is named as 'signage as smart media', the second type is named as 'signage as passive media', and the third type is named as 'signage as interactive media' is named. The results of this study will be useful guidelines for conducting further academic researches and R&D.

• Journal of Information Processing Systems
• /
• v.13 no.4
• /
• pp.778-804
• /
• 2017

Software today has become an inseparable part of our life. In order to achieve the ever demanding needs of customers, it has to rapidly evolve and include a number of changes. In this paper, our aim is to study the relationship of object oriented metrics with change proneness attribute of a class. Prediction models based on this study can help us in identifying change prone classes of a software. We can then focus our efforts on these change prone classes during testing to yield a better quality software. Previously, researchers have used statistical methods for predicting change prone classes. But machine learning methods are rarely used for identification of change prone classes. In our study, we evaluate and compare the performances of ten machine learning methods with the statistical method. This evaluation is based on two open source software systems developed in Java language. We also validated the developed prediction models using other software data set in the same domain (3D modelling). The performance of the predicted models was evaluated using receiver operating characteristic analysis. The results indicate that the machine learning methods are at par with the statistical method for prediction of change prone classes. Another analysis showed that the models constructed for a software can also be used to predict change prone nature of classes of another software in the same domain. This study would help developers in performing effective regression testing at low cost and effort. It will also help the developers to design an effective model that results in less change prone classes, hence better maintenance.

• Journal of Information Processing Systems
• /
• v.14 no.3
• /
• pp.751-770
• /
• 2018

Web applications are indispensable in the software industry and continuously evolve either meeting a newer criteria and/or including new functionalities. However, despite assuring quality via testing, what hinders a straightforward development is the presence of defects. Several factors contribute to defects and are often minimized at high expense in terms of man-hours. Thus, detection of fault proneness in early phases of software development is important. Therefore, a fault prediction model for identifying fault-prone classes in a web application is highly desired. In this work, we compare 14 machine learning techniques to analyse the relationship between object oriented metrics and fault prediction in web applications. The study is carried out using various releases of Apache Click and Apache Rave datasets. En-route to the predictive analysis, the input basis set for each release is first optimized using filter based correlation feature selection (CFS) method. It is found that the LCOM3, WMC, NPM and DAM metrics are the most significant predictors. The statistical analysis of these metrics also finds good conformity with the CFS evaluation and affirms the role of these metrics in the defect prediction of web applications. The overall predictive ability of different fault prediction models is first ranked using Friedman technique and then statistically compared using Nemenyi post-hoc analysis. The results not only upholds the predictive capability of machine learning models for faulty classes using web applications, but also finds that ensemble algorithms are most appropriate for defect prediction in Apache datasets. Further, we also derive a consensus between the metrics selected by the CFS technique and the statistical analysis of the datasets.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.21 no.1
• /
• pp.39-45
• /
• 2001

Fourier transform has been one of the most common tools to study the frequency characteristics of signals. With the Fourier transform alone, however, it is difficult to tell whether signal's frequency contents evolve in time or not. Except for a few special cases, the frequency contents of most signals encountered in the real world change with time. Time-frequency analysis methods are developed recently to overcome the drawbacks of Fourier transform, which can represent the information of signals in time and frequency at the same time. In this study, damage process of a cross-ply carbon fiber reinforced plastic (CFRP) under monotonic tensile loading was characterized by acoustic emission. Different kinds of CFRP specimens were used to determine the characteristics of AE signals. Time-frequency analysis methods were employed for the analysis of fracture mechanisms in CFRP such as mix cracking, debonding, fiber fracture and delamination.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.17 no.9
• /
• pp.458-463
• /
• 2016

New areas can be created by combining separate fields of study. Today, boundaries between fields are collapsing because of rapid progress in technologies, which is also the case in music. In 1969, jazz trumpeter and respected artist Miles Davis combined jazz, rock, and classical music into the fusion genre. Classical music is known to be strict, rigorous, and rigid, and it started to take a different form after experiments with musical crossovers. This study examines the potential of more diverse musical crossovers that musicians use to evolve a new genre. Several musicians in Korea have attempted musical crossovers by following global music trends. In the album, "Love and Peace," the classical music pieces "Flight of the Bumblebee" and Beethoven's "Fate" were arranged using a popular music style.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.26 no.6
• /
• pp.439-444
• /
• 2016

The definition of quality continues to evolve. In recent years, there has been growing interest in how to satisfy customers' potential needs with an emphasis on customer-oriented quality. Two-dimensional quality proposed by Kano provides a useful framework for discovering quality attributes critical to customer satisfaction and it is widely employed for product and service development. In Kano model, quality attributes are classified into attractive, one-dimensional, must-be, indifferent, and reverse ones. Finding attractive elements among them is important for achieving customer satisfaction effectively. However, Kano's classification method has limitations in dealing with customers' ambiguous and complex ideas. The customer response itself includes uncertainty and incompleteness. To overcome this problem, fuzzy methods are incorporated with Kano's classification in this paper. According to numerical comparisons, it is shown that the fuzzy Kano method is useful for accommodating various response of customer and is helpful to identify potential needs.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.12 no.7
• /
• pp.1263-1270
• /
• 2008

Recently, it is increasing the interest in previous web and web 2.0 which mean differentiation. The previous system is typical Static web based on client and server model, while web 2.0 mean next generation web which web change and evolve fundamentally. In this paper, I suggest that the module on RSS reader available under web 2.0 standards. A currently used RSS feed do correct the part distortion which ran be possible resolve the encoding problem of Hanguel and third-world language. The suggested module is implemented using Ajax. I developed the module for the use of effective contents on web 2.0 through the DragBox module based on the programming on mobility of Ajax and the design and implementation of automatic update module of RSS feed.