• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.615-616
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• 2006

Many manufacturing companies manage their production-related data for quality management and production management. Nevertheless, production related-data should be closely related to each other Stored data is mainly used to monitor their process and products' error. In this paper, we provide an enterprise-wide production data model for decision support system and product automation. Process data, quality-related data, and test data are integrated to identify the process inter or intra dependency, the yield forecasting, and the trend of process status. In addition, it helps the manufacturing decision support system to decide critical manufacturing problems.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.4 no.6
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• pp.1209-1221
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• 2010

Three dimensional (3D) video is expected to be an important application for broadcast and IP streaming services. One of the main limitations for the transmission of 3D video over IP networks is network bandwidth mismatch due to the large size of 3D data, which causes fatal decoding errors and mosaic-like damage. This paper presents a novel selective frame discard method to address the problem. The main idea of the proposed method is the symmetrical discard of the two dimensional (2D) video frame and the depth map frame. Also, the frames to be discarded are selected after additional consideration of the playback deadline, the network bandwidth, and the inter-frame dependency relationship within a group of pictures (GOP). It enables the efficient utilization of the network bandwidth and high quality 3D IPTV service. The simulation results demonstrate that the proposed method enhances the media quality of 3D video streaming even in the case of bad network conditions.

• The Korean Journal of Financial Management
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• v.8 no.2
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• pp.111-129
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• 1991

본 논문에서는 재정가격결정모형(裁定價格決定模型)(Arbitrage Pricing Model)을 기초로 우리나라 주식시장에 영향을 주는 거시경제변수가 무엇인가를 찾고자 하였다. 방법론면에서는 과거변수(過去變數)(lagged variables)에 의해서만 기대치를 형성시키는 AIRMA(Autoregressike Integrated with Moving Average) 방법을 이용하기보다는 마코프속성(屬性)(Markov Property)을 갖는 상태공간모형(狀態空間模型) (State Space Model)을 이용하여 보다 합리적인 거시경제 요인의 이노베이션을 하였다. 또한 단순한 요인분석(要因分析)(factor analysis)에 의한 요인추출은 요인의 표본의존성(標本依存性)(Sample dependency)이 심하므로 그룹간 요인분석(inter-battery factor analysis)을 행하여 추정(推定)된 요인(要因)(요인값 : factor score)과 요인수를 결정하여 관련 거시경제변수를 선택한다. 그룹간 요인분석을 위한 그룹을 형성할 때 그룹내에서는 동질성을 그룹간에는 이질성을 최대한 살리는 것이 필요한데, 이를 위해 군집분석(群集分析)(Cluster Analysis)을 사용한 것이 특징이다. 결론적으로 우리나라 주식시장에 영향을 미치는 거시경제요인(巨視經濟要因)으로 단위노동비율, 제조업제품재고지수, 채권프리미엄, 수출물가지수, 정부부문 통화공급, 회사채수익률, 종합주가지수 등 7가지가 있는 것으로 분석되고 있다.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.467-467
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• 2012

As the features of recent flood are spatially concentrated, loss of life and property increase by the impact of climate change. In addition to this the public interest in water control information is increased and socially reasonable justification of water control policy is needed. It is necessary to estimate the flood risk in order to let people know the status of flood control and establish flood control policy. For accurate flood risk analysis, we should consider inter-relation between causal factors of flood damage. Hence, flood risk analysis should be applied to interdependence of the factors selected. The Bayesian networks are ideally suited to assist decision-making in situations where there is uncertainty in the data and where the variables are highly interlinked. In this research, to provide more proper water control information the flood risk analysis is performed using the Bayesian networks to handle uncertainty and dependency among 13 specific proxy variables.

• Journal of Navigation and Port Research
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• v.47 no.2
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• pp.93-99
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• 2023

This study aimed to determine relationships among risk factors influencing container port operation using Bayesian network. Risk factors identified from prior studies were classified into five groups: human error, machinery error, environmental risk, security risk, and natural disasters. P anel experts discussed identified risk factors to fulfil conditional probability tables of the interdependence model. The interdependence model was also validated by sensitivity analysis and provided an interrelation of factors influencing the direction of each other. Results of the interdependence model were partially in line with results from prior studies while practices in the global port industry confirmed interrelationships of risk factors. In addition, the relationship between top-ranked risk factors can provide a schematic drawing of the model. Accordingly, results of this study can expand the prior research in the Korean port industry, which may help port authorities improve risk management and reduce losses from the risk.

• Korean Journal of Social Welfare
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• v.54
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• pp.35-64
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• 2003

This study is to explore experience on the inter-organizational linkages for vocational rehabilitation of people with psychiatric disabilities and to find out predictors affecting the linkages. This study used triangulation a way as to combine the advantages of both the qualitative and the quantitative approach. The qualitative approach is based on grounded theory by Strauss & Cobin. The quantitative research used the samples of 122 organizations, and was analyzed by multiple regression & logistic regression. The results are as follows. First, as results of in-depth interview, interviewees perceived linkage experience as 'turning the eyes on the other organization in community', namely 'the pursue of collaboration'. This concept is classified four types: initiative, cooperative, authoritative and passive type. Second, according to Tobin(1986)'s five phase of the closeness of inter-organizational linkages, our linkages were found to be in third phase, "coordination". Finally, predictors of the attempt of having linkages & linkage strengthening were analyzed by logistic regression & multiple regression. 'The experience of professional training on people with psychiatric disabilities' and 'the resource dependency' have statistically significant relation with the attempt to have linkages. 'The length of current service', 'the experience of professional training on people with psychiatric disabilities', and 'recognition about other organizational activities' are significantly related to strengthening linkage. Based on the results of this study, alternatives for promoting inter-organization linkages for vocational rehabilitation of people with psychiatric disabilities were proposed.

• Journal of KIISE:Software and Applications
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• v.31 no.1
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• pp.43-53
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• 2004

Component-based development(CBD) has acquired a substantial acceptance in both academia and industry as an effective inter-organizational reuse technology. A component framework in product line engineering(PLE) which consists of related components, connectors and their semantics has a greater potential for reusability than components. In frameworks, components are glued with association, dependency and connections. Problems occur like affecting the implementation code of components when they are glued and replaced because the association and dependency relationships between COTS components which are acquired for application development do not match exactly. Especially, a connector may not only connect related components, but also mate partially-matched COTS components fit together. However, little has been studied to date about connectors that can be used practically. In this paper, we present a meta-model for connectors and show how a connector can be designed and implemented in practice. We propose five main patterns of connectors. Proposed major patterns Provide design guidelines for practical and efficient connector configuration based on component framework. And also, applying techniques and applied case studies of the major patterns show greatly increased applicability and reusability of the component without component modification.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.42 no.9 s.339
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• pp.9-18
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• 2005

To make high-performance, low-power transistors beyond the technology node of 60 nm complementary metal-oxide-semiconductor field-effect transistors(C-MOSFETs) possible, the effect of electron mobility of the thickness of strained Si grown on a relaxed SiGe/SiO2/Si was investigated from the viewpoint of mobility enhancement via two approaches. First the parameters for the inter-valley phonon scattering model were optimized. Second, theoretical calculation of the electronic states of the two-fold and four-fold valleys in the strained Si inversion layer were performed, including such characteristics as the energy band diagrams, electron populations, electron concentrations, phonon scattering rate, and phonon-limited electron mobility. The electron mobility in an silicon germanium on insulator(SGOI) n-MOSFET was observed to be about 1.5 to 1.7 times higher than that of a conventional silicon on insulator(SOI) n-MOSFET over the whole range of Si thickness in the SOI structure. This trend was good consistent with our experimental results. In Particular, it was observed that when the strained Si thickness was decreased below 10 nm, the phonon-limited electron mobility in an SGOI n-MOSFT with a Si channel thickness of less than 6 nm differed significantly from that of the conventional SOI n-MOSFET. It can be attributed this difference that some electrons in the strained SGOI n-MOSFET inversion layer tunnelled into the SiGe layer, whereas carrier confinement occurred in the conventional SOI n-MOSFET. In addition, we confirmed that in the Si thickness range of from 10 nm to 3 nm the Phonon-limited electron mobility in an SGOI n-MOSFET was governed by the inter-valley Phonon scattering rate. This result indicates that a fully depleted C-MOSFET with a channel length of less than 15 m should be fabricated on an strained Si SGOI structure in order to obtain a higher drain current.

• Journal of Broadcast Engineering
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• v.12 no.6
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• pp.611-623
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• 2007

The H.264|AVC standard incorporates an intra prediction tool into inter frame coding. However, this leads to excessive amount of increase in encoding time, thus resulting in the difficulty in real-time implementation of software encoders. In this paper, we first propose an early decision on intra prediction coding and a fast intra prediction method using the characteristics of block contents and the context of neighboring block modes for the intra prediction in the inter frame coding of H.264/AVC. Basically, the proposed methods determine a skip condition on whether the $4{\times}4$ intra prediction is to be used in the inter frame coding by considering the content characteristics of each block to be encoded and the context of its neighboring blocks. The performance of our proposed methods is compared with the Joint Model reference software version 11.0 of H.264|AVC. The experimental results show that our proposed methods allow for 41.63% reduction in the total encoding time with negligible amounts of PSNR drops and bitrate increases, compared to the original Joint Model reference software version 11.0.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.4
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• pp.352-356
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• 2010

In this study, it is discussed how the directional property of the sound lateralization is influenced by proceeding or succeeding tone. The acoustic source applied here is a reference sound which has 0.5 msec interaural time difference(ITD). Based on this reference sound, interfering sounds with five levels of magnitude are applied to the subjects with four kinds of inter-stimuli time intervals(ISI). The interfering sounds are also added as two different types, proceeding tone and succeeding tone. Additionally, in order to investigate a frequency influence, the reference sound and the interfering sounds are generated by using 2kHz, 4 kHz and a white noise. As a result, the influence on lateralization by proceeding tone is lager than that by succeeding tone. It can consider this result as the effect of temporal masking on lateralization. Moreover, there are small differences of masking effect on lateralization by combinations of pure tone. This result shows that the dependency of frequency domain between reference sound and interfering sound is small on the sound lateralization.