• Journal of the Korean Geotechnical Society
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• v.18 no.4
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• pp.257-270
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• 2002

The Impact-Echo(IE) method has been used to evaluate the integrity of concrete structures. In this method, the P-wave velocity of concrete is a crucial parameter in determining the thickness of concrete lining, the location of cracks or other defects. In many field applications of the IE method, the P-wave velocity is obtained by testing the core or the portion of a structure where the exact thickness is known. Occasionally, however, the core can not be obtained in specific structures and the P-wave velocity determined from core testing may not be a representative value of the structure. This study introduces an IE-SASW method that may determine the P-wave velocity on a surface of each testing area using the Spectral Analysis of Surface Wave (SASW) method. Results obtained from numerical studies are presented in this paper (Part I), and results obtained from experimental studies are presented in the companion paper (Part II). In this paper, numerical analyses using ABAQUS were carried out to investigate the effectiveness and the limitations of the IE-SASW method.

• Proceedings of the CALSEC Conference
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• 1999.07b
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• pp.587-596
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• 1999

In this paper, we introduce the design and development of a web-based workflow management system. The goal of the developed system is to manage business processes occurring in the CITIS (Contractor Integrated Technical Information Services) environment. The system is composed of three main modules: Process Designer, Workflow Engine, and Client modules. The Process Designer is a module that provides the environment for the build-time function, which generates the specifications of processes. The module presents the capability of defining nested process models, which is powerful in particular for designing complex processes. Since the other two modules are implemented using pure Java technology, the Workflow Engine can be implemented on any platform and the Client programs can be accessed via the WWW interface. This indicates that there is no need to install any client programs at the client-sides. Users who has a connection to the internet with web browsers, such as Internet Explorer and Netscape Navigator, and has a proper right of access can utilize the normal client, monitoring client, and system administration client programs. Communications between the workflow engine and the clients are implemented using the java servlet mechanism. The workflow system can serve as the underlying platform of process management tool in CALS and CITIS environments. An example scenario of using the system is presented.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.3
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• pp.411-418
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• 2016

In accordance with global energy conservation policies such as MEPS(Minimum Energy Performance Standard), electric motor industry is moving to super-high-efficiency machines and research to develop IE4 (International Energy Efficiency Class4) motors has been launched. In this situation, SynRM (Synchronous Reluctance Motor) has been attracting attention in place of induction motor which hardly provides super premium efficiency. As a result, much research on SynRM is being performed at home and abroad. Also, some products have already been appearing in the market. Compared to induction motor, SynRM has better efficiency per unit area and wider operating range. Although the utilization of control system in synchronous motor results in higher prices, we still need to concentrate on developments of SynRM so as to comply with the new policies. This study demonstrated the electromagnetic design methods of super-premium SynRM while maintaining the frame of existing IE3 induction motor for blower. We documented the design procedures for generating high saliency which is the most essential and mechanical stress analysis is also treated. In conclusion, we proved the validity of our design by manufacturing and testing our SynRM models.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1999.04a
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• pp.343-343
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• 1999

• Pediatric Infection and Vaccine
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• v.23 no.3
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• pp.209-216
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• 2016

Purpose: This study aimed to evaluate and compare the characteristics of infective endocarditis (IE) between children and adults with congenital heart disease (CHD) at a single tertiary care center. Methods: In this retrospective medical record review, we extracted the demographic characteristics, diagnostic variables, and outcomes of patients diagnosed with IE and CHD between 2000 and 2016. Results: We identified a total of 14 pediatric patients (nine male; median age at diagnosis, 3 years). Of the 14 patients, six had a history of previous open heart surgery, while four had undergone tetralogy of Fallot repair, with transannular patch or Rastelli procedure. Among the 10 children with positive blood cultures, the most common isolated organism was Staphylococcus spp. (8/10, 80%). Eleven adult patients had IE and CHD. Among the adult patients, only four were diagnosed with CHD before IE, and ventricular septal defect was the most common CHD. The most common isolated organism was Streptococcus spp. (6/11, 55%). Compared with adult patients, pediatric patients had a higher incidence of previously diagnosed CHD (P=0.001), with Staphylococcus spp. as the causative organism (P=0.027). The median duration between the onset of symptoms and diagnosis of IE was 9 days in children and 42 days in adults (P=0.012). Conclusions: Significant differences with regard to the diagnosis and progress of IE were observed between children and adults. Age-adjusted and systematic reassessment may be necessary for the diagnosis and management of IE.

• International Area Studies Review
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• v.13 no.2
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• pp.445-474
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• 2009

This study tries to investigate the factors influenced on the performance by top management team's(TMT's) international entrepreneurship(IE) and firm's capabilities(marketing capability and R&D capability) of Korean Ventures. The research model and hypothesis set that TMT's IE directly affect to the performance directly affects and TMT's IE indirectly affect to the performance through the capabilities(marketing capability and R&D capability) by research prior studies. To verify research model, 115 high-technology based Korean ventures survey to be as samples by structured questionnaires and the data is tested by SEM(structural equation modeling) analysis. The results of analysis are as follow. First, there was no relationship between TMT's IE and performance. Second, the IE positively affected to firm's capabilities(marketing capability and R&D capability). Third, firm's internal capabilities positively affected to performance. These results only few TMT's IE cannot sufficiently affect to performance but IE should be propagated to marketing and R&D departments and then firm's performance can improved. This study respect to provide a meaningful implication to globalization and performance of Korean Ventures.

• Corrosion Science and Technology
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• v.2 no.5
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• pp.233-237
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• 2003

Pickling inhibitors can be used to form an adsorbed layer on the metal surface to hinder the discharge of H^+$ and dissolution of metal ions. Nitrogen-containing inhibitors were selected as corrosion inhibitors for mild steel (MS) in pickling acid process. In this study, the addition of inhibitor, the pickling temperatures and the pickling times were the parameters to investigate the effects on the inhibition efficiency (IE) for MS by using weight loss measurement. Preliminary results show that the IE increased with the increase in pickling time from 10 minutes to 60 minutes, and the IE also increased with the increase in temperature at room temperature and $40^{\circ}C$. At the higher temperature. the IE values are higher and almost independent with the pickling time. Furthermore, the potentiodynamic polarization, open circuit corrosion potential-time and corrosion current-time studies show that nitorgen-containing inhibitor behaves predominantly as cathodic polarization. The roughness test and SEM investigation are also studied in this paper.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.4
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• pp.813-818
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• 2015

In this paper, WiMedia Distributed-MAC protocol is adopted for development of a seamless N-screen wireless service. Furthermore, to provide the OSMU (One Source Multi Use) N-screen service through P2P streaming in the seamless D-MAC protocol, a new Multicast-free DRP Availability IE is proposed and analyzed. In this Multicast-free DRP Availability IE, indicating Multicast DRP Owner and Receiver is required. The ACK frame transmissions are not required for Multicast transmissions in P2P N-screen services. Using this property, the Multicast-free DRP Availability IE scheme is proposed to expand the number of time slots available for unicast and multicast DRP reservations. Simulation results show that our Multicast scheme enhances performances in vewpoints of DRP reservation conflict and throughput.

• 한국지구물리탐사학회:학술대회논문집
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• 2009.10a
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• pp.185-189
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• 2009

Integrated analysis of GPR, impact echo and impulse response for detection of the rear cavity of concrete was performed on the test-bed which was made in the same scale and component ratio to the real concrete structure. GPR survey may roughly delineate the location of the cavity, but applying the IE and IR technique to the test-bed, the location was clearly identified.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.8
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• pp.1796-1803
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• 2013

In this paper, a novel particle swarm optimization method based on IE3D is used to design a mobile communication microstrip patch antenna. The aim of the paper is to design and fabricate an inset fed rectangular microstrip antenna and study the effect of antenna dimensions length (L), width (W) and substrate parameters relative dielectric constant (${\varepsilon}r$), substrate thickness on radiation parameters of band width. PSO algorism was applied to IE3D, low resistance against, band width and advantage, were improved.