• Journal of Information Processing Systems
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• v.10 no.3
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• pp.429-442
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• 2014

In this paper, we investigated the use of seasonal autoregressive integrated moving average (SARIMA) time series models for fault detection in semiconductor etch equipment data. The derivative dynamic time warping algorithm was employed for the synchronization of data. The models were generated using a set of data from healthy runs, and the established models were compared with the experimental runs to find the faulty runs. It has been shown that the SARIMA modeling for this data can detect faults in the etch tool data from the semiconductor industry with an accuracy of 80% and 90% using the parameter-wise error computation and the step-wise error computation, respectively. We found that SARIMA is useful to detect incipient faults in semiconductor fabrication.

• Transactions of the Korean Society of Mechanical Engineers
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• v.11 no.3
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• pp.519-527
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• 1987

Simple procedures have been formulated to compute approximate natural frequency of nonlinear systems by the use of variational principle. These procedures are applicable to motion of large amplitudes, even to systems which are not linearizable. The results obtained by these procedures have been found to have good agreements with computer solutions and exact solutions for systems having piece-wise linear springs and polynomial springs.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.17 no.6
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• pp.3-10
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• 2007

In this paper we present related-key differential attacks on the block-wise stream cipher TWOPRIME. We construct various related-key differentials of TWOPRIME and use them to show that recovering related keys of TWOPRIME can be performed with a data complexity of $2^{14}$ known plaintext blocks and a time complexity of $2^{38}$ 8-bit table lookups.

• Journal of Korea Society of Industrial Information Systems
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• v.16 no.4
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• pp.107-117
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• 2011

Smartphones are widely used as a mobile communication devices with more advanced computing ability and connectivity than a contemporary feature phone. As the market expands, many brand-new smartphones are released and chosen by (potential) smartphone users. In spite of smartphone's popularity, little research of the factors affecting the evaluation of smartphones and their influences on smartphone choice have been performed. Therefore, we aim to analyze evaluation factors of smartphone selection and use in this research. We use Fuzzy Analytic Hierarchy Process method, a Multi-Criteria Decision Making (MCDM) model, to find the relative importance among the factors considering the fuzziness of pair-wise comparison using AHP. After reviewing related works and interviewing the focus group, we extract the five independent factors influencing the choice and use of a smartphone. Pair-wise comparison and triangle fuzzy numbers are used to calculate the relative importance of factors. We analyze not only the whole interviewees' responses, but the differences between smartphone users and non-users. Practical implications are delivered in concluding remarks.

• Journal of the Korean association of regional geographers
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• v.7 no.2
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• pp.82-96
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• 2001

The purpose of this study is to investigate the wise use and the management of intertidal environment. For tills purpose, we selected the Kanghwa island mudflat which is one of the most important intertidal region in Korea peninsula. The main research method is surface sediment and several map analysis. The results are as follows. (1) The study area is worldwide coastal wetland in view of ecology and geomorphology. But most of the salt marsh has been reclaimed since Japanese colonial period, the study area is mainly composed of mudflat. (2) The mean tidal regime of study area is 7.3m. From this tidal regime, the study area is subdivided into four distinct areas: the high intertidal area the middle intertidal area the low intertidal area and the shallow sea area terrestrial area near mudflat. (3) The mean particle size of surface sediment is sand 41.5%, silt 47.3%, clay 11.2%. This particle size pattern indicates the ecological characteristics of surface sediment of the study area. The proportion of clay is increasing to the open sea. (5) The pursuit of the wise use and the management must be implemented by the consideration of not only ecologic and sedimentary characteristics but also of the eco-tour site plan. And the entire use and management subject is different in each area.

• Journal of Korea Water Resources Association
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• v.48 no.4
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• pp.291-298
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• 2015

The aim of this study is that a theoretical formula for estimating the one-dimensional longitudinal dispersion coefficient is derived based on a transverse distribution equation for the depth averaged stream-wise velocity in open channel. In "Part I. Theoretical equation for stream-wise velocity" which is the former volume of this article, the velocity distribution equation is derived analytically based on the Shiono-Knight Model (SKM). And then incorporating the velocity distribution equation into a triple integral formula which was proposed by Fischer (1968), the one-dimensional longitudinal dispersion coefficient can be derived theoretically in "Part II. Longitudinal dispersion coefficient" which is the latter volume of this article. SKM has presented an analytical solution to the Navier-Stokes equation to describe the transverse variations, and originally been applied to straight and nearly straight compound channel. In order to use SKM in modeling non-prismatic and meandering channels, the shape of cross-section is regarded as a triangle in this study. The analytical solution for the velocity distribution is verified using Manning's equation and applied to velocity data measured at natural streams. Although the velocity equation developed in this study do not agree well with measured data case by case, the equation has a merit that the velocity distribution can be calculated only using geometric data including Manning's roughness coefficient without any measured velocity data.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.1
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• pp.185-201
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• 2014

The Yong-neup of Mt. Daeam, which was designated as Korea's National Monument No.246 in 1973, is a high moor, and it has been managed with the designation as an ecosystem conservation area, Ramsar wetlands, and wetland conservation area. With the closing of the officially announced 5-year period for 'No-Trespassing' on the ecosystem conservation area starting August, 2010, it becomes necessary to arrange a systematic management and conservation scheme in consideration of the access & use of the visitors and Yong-neup's potential change into land consequent on making it open to the public. This study thinks that in order to preserve the Yong-neup, it's necessary to prepare the conservation plan for the program operation for exterminating exotic species, development of replacement wetlands and nurseries, access limit through zone categorization, establishment of environment-monitoring system, institutional management support, and establishment of managing facilities, etc., and to make scientific approaches, such as survey on wetland ecosystem, establishment of inventories, wetland monitoring, and drawing up of wetland ecology maps, etc. In addition, it is required that there should be adequate considerations of restoration of slope faces, drains, artificial embankment, water-collecting wells, roads for military operations, and wild-boar-stricken areas, etc., and should be continuous and systematic management of Yong-neup through the wise use of residents' participation-style maintenance, organization of a consultative body, introduction of CEPA programs, and introduction of visiting facilities and alternative transportation system, etc.

• Journal of Acupuncture Research
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• v.33 no.2
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• pp.109-116
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• 2016

Objectives : Our primary objective lies in understanding the current landscape of translational research on acupuncture, moxibustion and pharmacopuncture. Methods : We searched our own selection of keywords of acupuncture, moxibustion and pharmacopuncture and translational research from three overseas databases (Pubmed, Scopus, Medicine) and four domestic databases (DBpia, KISS, Riss4u, Korea Med). Results : We have chosen 41 articles in total-40 articles on acupunture, 6 article on moxibustion(5 articles were duplicated in use in each category). Origin-wise, 48.8 %/24.8 %/17.0 % of our articles pool came from USA/China/Korea, respectively. UK, Austria, Thailand and Italy contributed the rest of our article pool. For those articles written in USA and China, review articles were the most common type. For the US articles, all 10 review articles were non-systematic reviews, while, for China's contribution, one out of 4 review articles were systematic review. Type-wise, our research pool's breakdown is as follows ; 17 review articles, 11 experimental research, 2 randomized controlled trials(RCT), 1 clinical trial, 4 conference reports, 1 letter, 1 study protocol and 4 uncategorized. Topic-wise, brain-neurology was most frequently referred with 8 articles, followed by parkinson's disease (3 articles) and epilepsy (2 articles). Conclusion : 1. In terms of research submission articles, Korea appears to be lacking translational research on acupuncture, moxibustion and pharmacopuncture, compared to USA and China, in our view. 2. Unlike the cases of USA and China, most of Korean translational research is limited to doing a T1 level of translational research. In order to bring bench-to-bedside to light. we believe, there should be more studies, and thereby a certain level of activation, to the T2 level of translational research in Korea. 3. Further, in our view there should be more efforts to improve article quality at the T1 level of translational research, which eventually becomes the fundamentals of the next level of research (i.e. T2 research), as well as to increase the number of research submissions, going forward.

• Journal of Korea Water Resources Association
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• v.46 no.6
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• pp.585-596
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• 2013

The objective of this study is to evaluate the hybrid downscaling method combined Step-Wise Scaling (SWS) method with Regional Climate Model (RCM) simulation data for climate change impact study on hydrology area. The SWS method is divided by 3 categories (extreme event, dry event and the others). The extreme events, wet-dry days and the others are corrected by using regression method, quantile mapping method, mean & variance scaling method. The application and evaluation of SWS method with 3 existing and popular statistical techniques (linear scaling method, quantile mapping method and weather generator method) were performed at the 61 weather stations. At the results, the accuracy of corrected simulation data by using SWS are higher than existing 3 statistical techniques. It is expected that the usability of SWS method will grow up on climate change study when the use of RCM simulation data are increasing.

• Journal of the Korea Society of Computer and Information
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• v.13 no.5
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• pp.229-236
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• 2008

In this paper, re proposed scheme that it safely exchange encrypted keys without Trust Third Party(TTP) and Pre-distributing keys in ubiquitous environments. Existing paper assume that exist a TTP or already pre-distributed encrypted keys between nodes. However, there methods are not sufficient for wireless environments without infrastructure. Some existing paper try to use the Diffie-Hellman algorithm for the problem, but it is vulnerable to Replay and Man-in-the middle attack from the malicious nodes. Therefore, Authentication problem between nodes is solved by modified the Diffie-Hellman algorithm using ${\mu}TESLA$. We propose safe, lightweight, and robust pair-wise agreement algorithm adding. One Time Password(OTP) using timestamp to modified the Diffie-Hellman in ubiquitous environments, and verify a safety about proposed algorithm.