• 한국시뮬레이션학회논문지
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• 제9권3호
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• pp.65-75
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• 2000

In recent years, significant advances in computers and communication technologies have made multimedia services feasible. As a result, various queuing models and cost models on architecture and data placement for multimedia server have been proposed. However, these analytical techniques use only probabilistic models to represent the behavior of a system, and then they have several limitations like accuracy. Simulation is a viable alternative to analytical model. It avoids many of the limitations associated with analytical techniques, allowing for more precise representation of system attributes like workload in program code. In this paper, we propose a simulation test bed that can evaluate performance of real-time multimedia server by using simulation model.

• 제어로봇시스템학회논문지
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• 제10권8호
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• pp.669-672
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• 2004

This paper considers the implementation and experiments of an open-loop Cylindrical Vibratory Gyroscope(CGV). An open-loop CGV composed of thin cylindrical vibrating element, electromagnetic drive and pick-off element with open-loop control was designed and fabricated. The experimental performance tests of the open-loop CGV were done using a temperature chambered rate table. Also, the limitations of open-loop CGV were analyzed and the solution for the limitations was proposed.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2014년도 춘계학술발표대회
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• pp.606-607
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• 2014

Due to Web Services' platform and language independent nature, many business corporations have used them for the integration of various applications. However, the growing amount of available Web Services on Web forms a new problem - how to select and recommend an appropriate Web Service that matches the user requirements. In this paper, we investigate recommendation methods in Web Services, and discuss their strength and limitations.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2012년도 추계학술발표대회
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• pp.918-919
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• 2012

Web Services have been used in a variety of applications and have become a key technology in developing business operations on the Web. However, despite the growing use of Web Services by large corporations, security is still a major concern that is slowing their deployment. In this paper, we give an overview of security vulnerabilities, review the existing solutions, and show their limitations.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2008년도 추계학술발표대회
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• pp.1469-1472
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• 2008

Honeynets have become one of essential tools in system and network security. As the importance of security has increased over the years, many researchers try to improve the overall Honeynet architecture. Due to their efforts, the Honeynets have evolved up to the third generation. However, the GenIII architecture has some limitations. In this paper, we address some of the limitations and provide solutions by redesigning the framework of data capture of Honeynets.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.95-96
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• 2023

The purpose of this study is to derive the limitations of the existing management system by analyzing the characteristics of the PC process to improve the PC construction project management system process. To overcome the limitations derived, we present a process of managing integrated information from the design-production-construction stage using QR codes and clouds. This is expected to help develop a PC construction project management system.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 추계학술대회 논문집
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• pp.797-803
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• 2009

The accurate prediction of dynamic characteristics of high speed rotors, such as gas turbines, is important to avoid the possibility of operating the machinery near the critical speeds or unstable speed regions. However, the dynamic analysis methods and softwares for gas turbines have been developed in the process of producing many gas turbines by manufacturers and most of them have seldom been disclosed to the public. Recently, commercial FEM softwares, such as SAMCEF, ANSYS and NASTRAN, started supporting some rotordynamics analysis modules based on 3-D finite elements. In this paper, the dynamic analysis method using commercial S/W, especially ANSYS, is attempted for the small-size gas turbine engine rotor, and the analysis capability and limitations of its rotordyamics module are evaluated for further improvement of the module. As the preliminary procedure, the rotordyamic analysis capability of ANSYS was tested and evaluated with the reference models of the well-known dynamics. The limitations in application of the rotordynamics module were then identified. Under the current capability and limitations of ANSYS, it is shown that Lee diagram, a new frequency-speed diagram enhanced with the concept of $H{\infty}$ in rotating machinery, can be indirectly obtained from FRFs computed from harmonic response analysis of ANSYS. Finally, it is demonstrated based on the modeling and analysis method developed in the process of the S/W verification that the conventional Campbell diagram, Lee diagram, mode shapes and critical speeds of the small-size gas turbine engine rotor can be computed using the ANSYS rotordynamics module.

• 한국소음진동공학회논문집
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• 제20권1호
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• pp.36-44
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• 2010

The accurate prediction of dynamic characteristics of high speed rotors, such as gas turbines, is important to avoid the possibility of operating the machinery near the critical speeds or unstable speed regions. However, the dynamic analysis methods and softwares for gas turbines have been developed in the process of producing many gas turbines by manufacturers and most of them have seldom been disclosed to the public. Recently, commercial FEM softwares, such as SAMCEF, ANSYS and NASTRAN, started supporting some rotordynamics analysis modules based on 3-D finite elements. In this paper, the dynamic analysis method using commercial S/W, especially ANSYS, is attempted for the small-size gas turbine engine rotor, and the analysis capability and limitations of its rotordyamics module are evaluated for further improvement of the module. As the preliminary procedure, the rotordyamic analysis capability of ANSYS was tested and evaluated with the reference models of the well-known dynamics. The limitations in application of the rotordynamics module were then identified. Under the current capability and limitations of ANSYS, it is shown that Lee diagram, a new frequency-speed diagram enhanced with the concept of $H{\infty}$ in rotating machinery, can be indirectly obtained from FRFs computed from harmonic response analysis of ANSYS. Finally, it is demonstrated based on the modeling and analysis method developed in the process of the S/W verification that the conventional Campbell diagram, Lee diagram, mode shapes and critical speeds of the small-size gas turbine engine rotor can be computed using the ANSYS rotordynamics module.

• 디지털융복합연구
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• 제12권2호
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• pp.563-570
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• 2014

정보보호의 중요성이 커지면서 안전행정부, 미래창조과학부, 교육부, 국가정보원 등 소관부처별 정보보안에 대한 심사기준을 제정하고 평가를 시행하고 있는 실정이다. 특히 2010년 G-ISMS, 2011년 개인정보보호법 시행 등 최근 정보보호의 중요성이 커지면서 보다 효과적인 정보보호 관리를 위한 노력이 커지고 있다. 이러한 각종 정보보호 인증과 심사는 공공기관의 정보보호 수준을 향상시키는데 많은 도움을 주고 있으나, 실무 기관에서는 연중 수시로 있는 소관부처별 인증심사로 인해 업무효율성이 저하되고 효과적인 보안관리에는 한계가 있다. 본 논문에서는 현재 공공기관을 대상으로 실시되는 정보보호 관리 심사기준을 분석하고, 한계점과 개선방향을 제시하고자 한다.

• 여성건강간호학회지
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• 제8권1호
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• pp.96-105
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• 2002

The purpose of this study is to identify the relation between functional limitation, functional disability and back pain during pregnancy. Data was collected by interview or self-report from 66 pregnant women between the gestational ages of 17 and 22 weeks who had experienced back pain from February 17 through July 28, 2001. The results of this study are as follows; 1. The prevalent mean week of back pain starting during pregnancy was 12.8. The mean pain intensity scores on the VAS during the past week and now were 5.6 and 3.7. The mean score on the functional limitations was 38.9. The mean score on the functional disability was 19.7. 2. The pain intensity on the past week was correlated with the pain intensity now (r=.339, p<0.01) and the functional limitations (r=.251, p<0.05). The pain intensity now was correlated with the functional limitations (r=.295, p<0.05) and the functional disability (r=.429, p<0.01). The functional limitations was correlated with the functional disability (r=.229, p<0.01). The higher pain intensity was the more functional limitation and functional disability occurred. 3. There was a statistically significant correlation between the pain intensity now and the type of housing (t=-2.051, p=.045), and back pain history before pregnancy (t=-2.429 p=.003). 4. There was a statistically significant correlation between the functional limitation and income (F=2.803, p=.047) and back pain history before pregnancy (t=-3.225, p=.002). There was a statistically significant correlation between the functional disability and back pain history before pregnancy (t=-3.058 p=.003). In conclusion, we found that a history of back pain was an important factor when predicting back pain and functional disability and limitation during pregnancy. The nurse and the prenatal educator should detect risk factors of back pain early in pregnancy and manage continuously though pregnancy.