• 한국항해항만학회지
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• 제44권5호
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• pp.407-413
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• 2020

In this paper we examined a novel extension of the convergence empirics for the maritime business cycle which considers structure breaks and/or changes. To provide theoretical justification, the convergence hypothesis uses the relaxed assumption to technology shocks. Based on the recent empirical results provided by Kim and Chang (2020), we consider nonlinear dynamics that capture the properties on structural changes in the equilibrium adjustment process. This approach bridges the gap between the theoretical framework and empirical specifications. In particular, we applied the convergence hypothesis to the multiple structure change model for the maritime business cycle. Our application to the maritime data showed support of the convergence hypothesis allowing multiple structure changes during the high volatile period and offers additional insight into the forecasting maritime business cycles.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제13권3호
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• pp.217-233
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• 2009

The purpose of this study is to describe how dynamic geometry systems can be useful in proof activity; teaching sequences based on the use of dynamic geometry systems and to analyze the possible roles of dynamic geometry systems in both teaching and learning of proof. And also dynamic geometry environments can generate powerful interplay between empirical explorations and formal proofs. The point of this study was to show that how using dynamic geometry software can provide an opportunity to link between empirical and deductive reasoning, and how such software can be utilized to gain insight into a deductive argument.

• 대한수학교육학회지:수학교육학연구
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• 제13권2호
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• pp.159-178
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• 2003

본 연구는 초등 수학 교재에서 정당화 과점이나 문제 해결 과정에서 활용되는 추론을 분석한 것이다. 본 연구의 분석 결과, 한 가지 전형적인 예에 대한 국소적 연역 추론이 가장 전형적인 특징으로 드러났으며, 사각형에 대한 몇 가지 명제는 연역 추론으로 정당화할 뿐 아니라 일반성을 요구하고 있는 것으로 드러났다. 또한, 열거에 의한 귀납 주론은 그리 많이 활용되고 있지 않으며, 구체물을 통한 유추가 밭이 활용되고 있음을 알 수 있었다. 전형적인 한 가지 예에 대한 설명은 Miyazaki가 제시한 예에 의한 설명이나 Semadeni가 제시한 활동 증명과 유사한 면을 지니고 있지만, 학생들의 학년 단계가 높아지더라도 계속 낮은 수준 머물러 있는 점이 문제점으로 부각되었다. 또한, 사각형의 일반적인 성질을 다루는 몇몇 명제는 Piaget의 이론에 비추어 너무 어려운 것으로 분석되었다. 본 연구에서는 이러한 문제점을 해결할 수 있는 방한으로서 보다 점진적인 추론의 지도를 제안하였는바, 전형적인 예에 대한 경험적 정당화, 전형적인 예에 대한 경험으로부터 추측의 구성, 다양한 예에 대한 추측의 타당성 조사, 일반성에 대한 스키마 형성, 함의 관계의 이해를 위한 기초 경험의 다섯 가지 수준이다.

• Ocean and Polar Research
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• 제33권1호
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• pp.77-83
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• 2011

In this study we examined the economic value of restoration technology for oil spill using contingent value methods. One and one half approach to questionnaires can be taken when analyzing tax payer situations as well as single bound approach. The results of the empirical analysis suggest three conclusions. First, the economic value of the restoration technology considered are estimated to be between 8,439 won to 11,867 won per month. Second, the WTP is estimated differently depending on the approaches, OOHB and SB, and the degrees of difference are very sensitive to the model specifications. This empirical result supports the argument for using interval for the economic value when using CVM. Third, the empirical results may provide useful input to policy authorities attempting to estimate the economic justification of the R&D investment for developing an ocean environmental restoration technology.

• East Asian mathematical journal
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• 제37권4호
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• pp.443-460
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• 2021

This study analyzes the characteristics of elementary math gifted classes through the development and application of teaching and learning materials. We used the guided reinvention methods including quasi-experiential perspectives. To this end, the applicability of Lakatos' quasi-empirical mathematical philosophy in elementary mathematics was examined, and the criteria for the development of teaching and learning materials for gifted students were presented, and then this study was conducted in this theoretical background. The subjects of the study were 21 elementary students at P University's Institute of Science and Gifted Education, and non-face-to-face real-time classes were conducted. Classes were divided into introduction, deployment1, deployment2, organization stages, and in each stage, small group cooperative learning was conducted based on group activities, and in this process, the characteristics of elementary mathematics gifted were analyzed. As a result of the study, elementary mathematics gifted students did not clearly present the essence of justification in the addition algorithm of fractions, but presented various interpretations of 'wrong' mathematics. They also showed their ingenuity in the process of spontaneously developing 'wrong' mathematics. On the other hand, by taking interest in new mathematics starting from 'wrong' mathematics, negative perceptions about it could be improved positively. It is expected that the development of teaching and learning materials dealing with various and original topics for the gifted students in elementary school will proceed through follow-up research.

• Journal of the Korean Statistical Society
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• 제23권1호
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• pp.79-88
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• 1994

This paper concerns the problem of estimating the spectral density function in the analysis of stationary time series data. A kernel type estimate is considered, which entails choice of bandwidth. A data-driven bandwidth choice is proposed, and it is obtained by plugging some suitable estimates into the unknown parts of a theoretically optimal choice. A theoretical justification is give for this choice in terms of how far it is from the theoretical optimum. Furthermore, an empirical investigation is done. It shows that the data-driven choice yields a reliable spectrum estimate.

• Asia pacific journal of information systems
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• 제20권3호
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• pp.91-114
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• 2010

An IT system within a company play increasingly important role as a significant part of corporate assets. The IT system possesses an extraordinary ability to improve an organization's efficiency, effectiveness and productivity by providing competitive advantages and improving strategic business decision capabilities. Indeed, providing a more secure IT environment, improving employee productivity and enhancing business process and strategic decision capabilities are key areas to improve corporate performance. However, existing research on IT ROI of return on IT investments does not provide solid justification to stakeholders. In this paper, we analyze the IT investment during the past 28 years from 1982 to 2009 and present the results in two dimensions. First, we show the IT solution implementation analysis by years and industries based on 1,240 IT success cases from 8 different sources such as major Korea IT newspaper, IT magazines, and IT vendors. Then, the paper presents the relationship between IT capability through IT success cases and corporate business performance among 32 industries.

• 대한수학교육학회지:수학교육학연구
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• 제11권2호
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• pp.385-402
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• 2001

The purpose of this study is to conceptualize 'proof' school mathematics. We based on the assumption the following. (a) There are several different roles of 'proof' : verification, explanation, systematization, discovery, communication (b) Accepted criteria for the validity and rigor of a mathematical 'proof' is decided by negotiation of school mathematics community. (c) There are dynamic relations between mathematical proof and empirical theory. We need to rethink the nature of mathematical proof and give appropriate consideration to the different types of proof related to the cognitive development of the notion of proof. 'proof' in school mathematics should be conceptualized in the broader, psychological sense of justification rather than in the narrow sense of deductive, formal proof 'proof' has not been taught in elementary mathematics, traditionally, Most students have had little exposure to the ideas of proof before the geometry. However, 'proof' cannot simply be taught in a single unit. Rather, proof must be a consistent part of students' mathematical experience in all grades, in all mathematics.

• 연구윤리
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• 제4권1호
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• pp.23-29
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• 2023

Purpose: While prior research has identified ethical issues in marketing research, more research needs to identify specific ethical behaviors that marketing researchers should adopt. This research addresses this gap by identifying a few ethical behaviors that marketing researchers should consider. Research design, data and methodology: The present study has a justification to collect adequate textual data in the current literature using screening process based on the marketing ethics topics and themes, and ethical behaviors of marketing researchers. Results: Based on the literature analysis, a marketing ethics model, which included the principles of fairness, honesty, responsibility, and respect for stakeholders. Since the rise of e-commerce and technology, a growing demand for a method to analyze website user behavior has been growing. Researchers in the field of marketing are responding to this demand by creating innovative interactive platforms. Conclusions: The term "ethical practices in market research" refers to a collection of best practices that, when followed, increase the likelihood that the research carries out is ethical, fair, and accurate. Because there needs to be more theoretical work done on the topic, there should be more empirical studies on ethical behaviors in marketing research.

• Restorative Dentistry and Endodontics
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• 제49권2호
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• pp.21.1-21.8
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• 2024

Objectives: This paper aims to serve as a useful guide for sample size determination for various correlation analyses that are based on effect sizes and confidence interval width. Materials and Methods: Sample size determinations are calculated for Pearson's correlation, Spearman's rank correlation, and Kendall's Tau-b correlation. Examples of sample size statements and their justification are also included. Results: Using the same effect sizes, there are differences between the sample size determination of the 3 statistical tests. Based on an empirical calculation, a minimum sample size of 149 is usually adequate for performing both parametric and non-parametric correlation analysis to determine at least a moderate to an excellent degree of correlation with acceptable confidence interval width. Conclusions: Determining data assumption(s) is one of the challenges to offering a valid technique to estimate the required sample size for correlation analyses. Sample size tables are provided and these will help researchers to estimate a minimum sample size requirement based on correlation analyses.