• The Korean Journal of Applied Statistics
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• v.35 no.5
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• pp.645-655
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• 2022

In this paper, we investigate automatic functions for time series forecasting in R system and compare their performances. For the exponential smoothing models and ARIMA (autoregressive integrated moving average) models, we focus on the representative time series forecasting functions in R: forecast::ets(), forecast::auto.arima(), smooth::es() and smooth::auto.ssarima(). In order to compare their forecast performances, we use M3-Competiti on data consisting of 3,003 time series and adopt 3 accuracy measures. It is confirmed that each of the four automatic forecasting functions has strengths and weaknesses in the flexibility and convenience for time series modeling, forecasting accuracy, and execution time.

• The monthly packaging world
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• s.373
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• pp.83-85
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• 2024

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.803-806
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• 2012

On this paper, various analysis methods has been applied to analyze and forecast the maximum electrical power needs, which is regarded as a nonlinear dynamic system. To understand the characteristic of complicated system, we used TISEAN package and evaluate the chaotic characteristic of time series obtained from electrical power demand using it. TISEAN package offers various algorithms and codes to analyze time series of nonlinear system effectively.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.9
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• pp.1596-1601
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• 2006

To customer management finds and forecast customer's various pattern more easily and conveniently rising by important topic that control corporation's success and failure, mmy corporations are introducing CRM and eCRM fast. At past, customer management had been managed by statisticians or special statistics package but it is trend been alternating gradually by datamining technique to do to computerize statistics process based on sudden development of IT. Field that this datamining is used representatively is CRM, eCRM. This paper applied datamining using GA referencing customer data or discount store and sale data or 2004 years. forecasted 2005 years melancholy customer by datamining and proved datamining through comparison with actuality customer data is how effective to eCRM.

• Journal of the Korean Society for Library and Information Science
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• v.33 no.4
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• pp.85-111
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• 1999

This study represents an attempt to forecast the increasingly complex and dynamic interplay between the transformation of media and collection management function in the networked environment. As the importance of electronic media rather than printed media is emphasized, there is a need to shift from the traditional collection management to content management for collection development strategy. In order to satisfy the needs of library users who have thirst for more various information, the traditional function of collection management has limitations. Therefore, we suggest that the future collection management must shift from the traditional collection management to content management.

• Korean Journal of Construction Engineering and Management
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• v.7 no.2 s.30
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• pp.138-147
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• 2006

The objective of this research is to explore a more precise forecasting method by applying Case-based Reasoning (CBR). The newly suggested method in this study enables project managers to forecast monthly expenditures with less time and effort by retrieving and referring only projects of a similar nature, while filtering out irrelevant cases included in database. For the purpose of accurate forecasting, 1) the choice of the numbers of referring projects and 2) the better selection among three levels ? which include a 20-work package level, a 7-major work package level, and a total sum level analysis, were investigated in detail. It is concluded that selecting similar projects at $12{\sim}19%$ out of the whole database will produce a more precise forecasting. The new forecasting model, which suggests the predicted values based on previous projects, is more than just a forecasting methodology; it provides a bridge that enables current data collection techniques to be used within the context of the accumulated information. This will eventually help all the participants in the construction industry to build up the knowledge derived from invaluable experience.

• The Journal of Information Systems
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• v.16 no.4
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• pp.243-268
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• 2007

It is critical to manage risks to complete IS(Information Systems) projects successfully. Identifying risk factors would be the first step for the project risk management. Previous research has discussed the issue with various points of view, such as different risk factors based on project types and roles involved in their projects. This paper empirically explored how people perceive different risk factors by project development methodology, between self-developing IS using programming language like C, Visual Basic and adapting software package already developed by software venders like ERP, CRM packages. There are researches regarding project risk factors for project management in the several point of views. And there are also researches regarding comparison between self-developing and adapting software packages methodology in IS project. However, there are no study on project risk factors comparison between self-developing IS using programming language and adapting software packages already developed by software venders in IS project. This research can be differentiated from previous ones, because it was considered both point of project risk management and development methodology in IS project. This research results implied meaningful messages to enterprise company to be planned IS projects and people who involved in IS projects. They should consider and need to prepare differently according to each development methodology for preventing project risks. It makes them reduce project risks in each case and complete successfully IS projects. Especially, if they have no experiences for implementing software packages, they can forecast the project risks and prepare them in advance.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.6
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• pp.1376-1379
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• 2009

Recently many Hotels have implemented and operated the Hotel Information System(HIS). These HIS-implementation evoke the significant changes in hotel management. So many interest and researches in HIS has received the spotlight from the hotel managements. Many researcher about HIS focused on the Critical Success Factors (CSF) from the viewpoint of HIS implementation. At this moment we need also the research about significance change of CSF with the laps of time. This kind of research are very critical for the successful operation of HIS. To achieve the objectives of this paper, the Innovation-Theory of E. M. Roger was implemented. As the result of this research we can get the various maturity point of each CSF with the laps of time. For the data gathering many major hotel in Korea were interviewed, and 84 valid questionaires were used for data analysis. The Cronbach's ${\alpha}$ was 0.7239, which means all data were significant.