• Journal of Satellite, Information and Communications
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• v.1 no.2
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• pp.32-37
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• 2006

ETRI has been developing the Ka-band Antenna subsystem for COMS(Communications, Ocean, and Meteorological Satellite) which will be launched at the end of 2008. The antenna subsystem employs the two parts: East Panel and West panel of spacecraft. ETRI in cooperation with domestic companies are under design phase for the antenna subsystem development. This paper focuses in the Ka-band reflector pointing error analysis to verify the antenna subsystem performance specification, especially EOC gain variation etc. The analysis performed is that induced by reflector surface deformation as a result of thermo elastic distortion. Beam pattern variations are verified by the use TICRA

• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.1
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• pp.27-33
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• 2011

In this paper, for a software-based Global Positioning System receiver (SGR), the principle capturing Global Positioning System (GPS) signal is researched extensively in order to analyze the processing of the GPS raw data signal at the lowest level, and the process of capturing the GPS signal was simulated by Matlab. The simulation results show the accuracy and the feasibility of this method, which is comparable to study under a true environment. We know that the improvement of the receiving facilities is of very vital significance to the performance of this system, and the fine frequency can be found through comparing phases within a few tens of Hertz.

• Journal of the Korean Operations Research and Management Science Society
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• v.34 no.4
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• pp.1-14
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• 2009

This study empirically tests post-M&A performance through competitiveness variables based on extensive firm-based panel data over the past 26 years in the world steel industry. Different measures of profitability, productivity, efficiency, market share, and growth rate which are considered as critical factors of competitiveness are used in the analysis. In particular, this paper tries to separate M&A samples into two cases; horizontal integration (between steel makers) and vertical integration (between steel makers and iron ore suppliers/steel consuming firms). Merged firms show significant improvement in competitiveness relative to other individual firms in the steel industry.

• Steel and Composite Structures
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• v.18 no.3
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• pp.711-737
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• 2015

Steel Plate Shear Walls (SPSWs) have been accepted widely as an effective lateral load resisting system. For seismic performance evaluation of a multi-story building with SPSWs, detailed finite element models or a strip model can be used to represent the SPSW components. However, such models often require significant effort for tall or medium height buildings. In order to simplify the analysis process, discrete elements for the framing members can be used. This paper presents development of a simplified equivalent braced model to study the behavior of the SPSWs. The proposed model is expected to facilitate a simplification to the structural modeling of large buildings with SPSWs in order to evaluate the seismic performance using regular structural analysis tools. It is observed that the proposed model can capture the global behavior of the structures quite accurately and potentially aid in the performance-based seismic design of SPSW buildings.

• Korean Journal of Remote Sensing
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• v.16 no.2
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• pp.135-143
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• 2000

Ocean Scanning Multispectral Imager (OSMI) is a payload on the Korean Multi-Purpose SATellite (KOMPSAT) to perform global ocean color monitoring for the study of biological oceanography. HOMPSAT was launched 21 December 1999. The radiometric performance of OSMI is analyzed for various gain settings in the viewpoint of the instrument developer for OSMI calibration and application based on its ground performance data measured before launch. The radiometric response linearity and dynamic range are analyzed and the dynamic range is compared with the nominal input radiance for the ocean and the land. The noise equivalent radiance (NER) corresponding to the instrument radiometric noise is compared with the radiometric resolution of signal digitization (1-count equivalent radiance). The best gain setting of OSMI for ocean monitoring is recommended. This analysis is considered to be useful for the OSMI mission and operation planning, the OSMI image data calibration, and users' understanding about OSMI image quality.

• Structural Engineering and Mechanics
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• v.21 no.1
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• pp.83-100
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• 2005

This paper presents results from a study to extend a performance-based shearwall selection procedure to take into account the contributions of nonstructural finish materials (such as stucco and gypsum wallboard), construction quality issues, and their effects on the displacement performance of engineered wood shearwalls subject to seismic loading. Shearwall performance is evaluated in terms of peak displacements under seismic loading (characterized by a suite of ordinary ground motion records) considering different combinations of performance levels (drift limits) and seismic hazard. Shearwalls are analyzed using nonlinear dynamic time-history analysis with global assembly hysteretic parameters determined by fitting to actual shearwall test data. Peak displacement distributions, determined from sets of analyses using each of the ground motion records taken to characterize the seismic hazard, are postprocessed into performance curves, design charts, and fragility curves which can be used for risk-based design and assessment applications.

• International Commerce and Information Review
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• v.10 no.3
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• pp.221-238
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• 2008

This paper examined the supply chain management partnerships factors and business performance in textile industry. To build a global network, we should consider the following critical factors such as lead-time reduction, information sharing, and inventory management. The purpose of this study is to focus on QR (Quick Response) of SCM in textile industries to clarify which of the SCM factors contribute to business performance for the SCM firms. Based on the analysis of eighth-six cases, the following results were found. First, partnerships factors of supply chain management have a positively significant influence on responsiveness of supply chain management. Second, partnerships factors of supply chain management have a positively significant influence on flexibility of supply chain management. This study suggests that partnerships are main factors for the business performance. Especially, our empirical evidence shows that capacity of firms practicing SCM, information techniques, and partnerships make the firms' business performance more responsive and flexible.

• The Journal of Information Systems
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• v.18 no.2
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• pp.61-81
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• 2009

Numerous small and medium-sized manufacturing companies have implemented or plan to introduce ERP for their own survival in the highly competitive global market. Despite of increasing number of companies implementing ERP, there has been few research on evaluation of ERP performance in small and medium manufacturers. Thus, in this paper, the impact of ERP implementation on the organizational performance based on Balanced Score Card is investigated and also critical success factors are discovered. The results of analysis show positive relationships between the ERP implementation and organizational performance. This paper suggests some practical implication on the ERP implementation to the practitioners.

• Journal of the Korea Safety Management & Science
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• v.16 no.2
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• pp.121-129
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• 2014

The purpose of this paper is to evaluate the impact of green practice on firm's performances. It focuses on the performance of the firm that already accredited as an excellent green practice firm by the Corporate Governance Service. The regression analysis method was chosen to measure firm performance. This paper also investigate how the performance of green practice are related to some factors such as levels of accredition, R&D cost, and R&D capitalization. This result will give an insight of constructive directions for increasing of firm performance.

• Earthquakes and Structures
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• v.26 no.3
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• pp.175-189
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• 2024

Aiming at studying the plastic hinge (PH) evolution regularities and failure mode of rocking wall moment frame (RWMF) structure in earthquakes, the whole-working history analysis of seismic performance state of RWMF structure based on co-operation performance and PH evolution was carried out. Building upon the theoretical analysis of the elastic internal forces and deformations of RWMF structures, nonlinear finite element analysis (FEA) methods were employed to perform both Pushover analysis and seismic response time history analysis under different seismic coefficients (δ). The relationships among PH occurrence ratios (R_ph), inter-story drifts and δ were established. Based on the plotted curve of the seismic performance states, evaluation limits for the R_ph and inter-story drifts were provided for different performance states of RWMF structures. The results indicate that the R_ph of RWMF structures exhibits a nonlinear evolution trend of "fast at first, then slow" with the increasing of δ. The general pattern is characterized by the initial development of beam hinges in the middle stories, followed by the development towards the top and bottom stories until the beam hinges are fully formed. Subsequently, the development of column hinges shifts from the bottom and top stories towards the middle stories of the structure, ultimately leading to the loss of seismic lateral capacity with a failure mode of partial beam yield, demonstrating a global yielding pattern. Moreover, the limits for the R_ph and inter-story drifts effectively evaluate the five different performance states of RWMF structures.