• Journal of the Earthquake Engineering Society of Korea
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• v.5 no.2
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• pp.33-47
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• 2001

성능에 기초한 내진설계에서는 구조물이 보유하고 있는 능력을 효과적으로 파악하기 위해서 비선형 정적 해석이 적용되고 있다. 그러나 비선형 정적해석은 고차모드에 대한 효과를 고려하지 못함으로써 고층구조물이나 비정형 구조물과 같은 경우에는 정확한 비선형 지진응답의 산정과 내진성능을 평가하는데 문제점을 가지고 있다. 본 연구에서는 건축구조물의 선형 및 비선형 지진응답 평가를 위하여 응답 스펙트럼해석을 통하여 얻어지는 층전단력으로부터 층하중을 산정하는 유사동적해석법이 적용되었다. 제안된 방법을 비선형 정적 해석에 적용하여 구조물의 비선형 자동응답을 비선형 시간이력해석의 결과와 비교하였다. 기존의 층분포하중에 의한 비선형 지진응답과 비교하였으며, 제안된 방법에 의한 지진 응답이 구조물의 비선형 거동특성을 가장 정확하게 표현하였다. 그러므로 본 연구에서 제안된 방법을 사용하여 비선형 정적 해석을 수행한다면 비교적 명확한 건축물의 비선형 거동특성과 내진성능을 평가할 수 있을 것으로 판단된다.

• Aerospace Engineering and Technology
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• v.13 no.1
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• pp.20-26
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• 2014

In this paper, yield stress, tangent modulus and failure strain were varied to ascertain the influence of impact response such as impact force histories and residual energy. And the buckling behavior of FML(Fiber Metal Laminates) were analyzed using numerical method. A number of analyses on FML and aluminum panel were conducted for shear and compression loading to compare the capability of stability. And to evaluate the static performance, static analysis has performed for box beam structure. Low-velocity impact analysis has performed on FML made of aluminum 2024 sheet and glass/epoxy prepreg layers. And the buckling and static performance of FML have been compared to aluminum using the analysis results. For the comparison of structural performance, similar analyses have been carried out on monolithic aluminum 2024 sheets of equivalent weight.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.28 no.3
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• pp.605-615
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• 2018

Due to the rapid growth of the Internet of Things market, the use of the C/C++ language, which is the most widely used language in embedded systems, is also increasing. To improve the quality of code in the C/C++ language and reduce development costs, it is better to use static analysis, a software verification technique that can be performed in the first half of the software development life cycle. Many programs use static analysis to verify software safety and many static analysis tools are being used and studied. In this paper, we use Clang static analysis tool to check security weakness detection performance of verified test code. In addition, we compared the static analysis results of the test codes applied with the source obfuscation techniques, layout obfuscation, data obfuscation, and control flow obfuscation techniques, and the static analysis results of the original test codes, Analyze the detection ability impact of the Clang static analysis tool.

• Journal of Korean Association for Spatial Structures
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• v.9 no.4
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• pp.49-59
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• 2009

The seismic responses of small-scale spatial frames such as school gymnasiums are usually evaluated using static analysis, although time-history analysis should be carried out to fully incorporate the dynamic responses of the structures against seismic motions. In this study, advanced static analysis procedures arc presented for school gymnasiums that will improve the performance evaluation against seismic motions. The seismic loads are approximated by equivalent static loads corresponding to the two performance levels; i.e., Levels 1 and 2 defined by the Japanese building standard. The importance of utilizing the eigenmode in the load pattern is discussed. Simple static analysis procedures are presented for evaluation of maximum vertical acceleration. It is shown that the static analysis for Level 2 input significantly underestimates the responses by dynamic analysis; however, the inelastic responses for Level 2 are shown to be successfully evaluated using the equivalent linearization that is similar to the $^{\circ}$Dmethod based on calculation of limit strength$^{\circ}{\pm}$ for building frames in Japan.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.2A
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• pp.59-69
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• 2011

Nonlinear static procedures (NSPs) basing on the concept of performance based seismic design have become one of the promising procedures for seismic evaluation of buildings. Although it needs much less computational cost compared to nonlinear time history analysis (NTHA), its usages are limited to simple structures by its inherent restriction to structures wherein the fundamental mode dominates the response. Several new nonlinear static procedures (Modal Pushover Analysis; MPA and Improved Modal Pushover Analysis; IMPA) which can consider higher modes effect were introduced. Nonetheless, its applicability for complex structures such as cable-stayed bridge has not studied yet. This paper focuses on applicability of nonlinear static procedures for the seismic analysis of cable-stayed bridges. Moreover, reliability indexes which can predict analysis procedure's accuracy are introduced.

• Journal of the Korea Concrete Institute
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• v.22 no.4
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• pp.489-498
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• 2010

The performance evaluation of reinforcement concrete structure is carried out as a function of the following performance influencing factors: (1) the strength of concrete, (2) longitudinal reinforcement, (3) transverse reinforcement, (4) aspect ratio, and (5) axial force. With various values of the five parameters, eigenvalue analysis and non-linear static analysis were performed to investigate the structural yield displacement, yield basis shear force, and static performance of ductility ratio. In addition, the performance evaluation is carried out according to the modified capacity spectrum method (FEMA-440) using the results of non-linear static analysis, and the effect of each parameter on performance point is analyzed. Based on the result of eigenvalue analysis and non-linear static analysis indicates, that the natural period and the ductility ratio are affected more by the structural properties than the material properties. In case of the analysis of the criterion of performance points, the effect of section shape is one of the important factors together with natural period and ductility ratio.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2009.05a
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• pp.179-183
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• 2009

본 연구는 공작기계중 대표적인 CNC LATHE의 검사항목에 관한 문헌연구를 통하여 기초 정밀도 개선 부품 적용 및 정적, 동적 정밀도 보정을 위한 기초 자료를 제시 한다. 그리고 공작기계의 기본 성능과 검사항목과의 관계를 정량적으로 연구하여 각 항목별 허용치를 제시함으로 고품질의 제품을 생산할 수 있는 데이터베이스와 관련 지침을 소개한다.

• Review of KIISC
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• v.16 no.5
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• pp.45-54
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• 2006

버퍼 오버플로우는 C 언어로 작성한 소프트웨어에 보안 취약점을 남기는 대표적인 원인이다. 프로그램 정적 분석기법을 통해 버퍼 오버플로우 취약점을 검출하는 방법은 버퍼 오버플로우 취약점을 활용한 다양한 보안 공격에 대한 근본적인 해결책이 될 수 있다. 본 고에서는 버퍼 오버플로우 취약점을 검출할 수 있는 몇 가지 정적 분석 도구들의 특징과 성능을 살펴보고, 보다 효율적이고 정확한 버퍼 오버플로우 정적 분석 도구를 개발하기 위한 우리의 연구 성과를 소개한다.

• Journal of the Society of Disaster Information
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• v.19 no.4
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• pp.851-858
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• 2023

Purpose: A study was conducted to ensure the structural safety of a raised girder bridge with improved cross-sectional efficiency compared to the conventional PSC girder. For this purpose, the cross-sectional specifications such as girder length, height, and width were determined, the arrangement of the tendons was designed, and the practical performance of the raised girder under static and dynamic loads was verified. Method: The static performance experiment examined the serviceability limit state by measuring behavioral responses such as deflection and cracking to primary and secondary static loads. In addition, the dynamic load loading experiment measured the acceleration and displacement behavior response over time to calculate the natural frequency and damping ratio to examine the usability limit state. Result: As a result of the static performance test, the deflection value based on the maximum applied load showed stable behavior, and the crack width measured at the maximum applied load level was very small, satisfying the serviceability limit state. In addition, a natural frequency exceeding the natural frequency calculated during the design of the dynamic loading experiment was found, and a damping ratio that satisfies the current regulations was found to be secured.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.221-224
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• 2008

Recently various types of prefabricated pier has been developed. In this paper, prefabricated composite columns with core steel elements embedded in concrete were proposed, which has no prestressing. Based on the previous research on composite columns with low steel ratio, the column were designed. A simple bolt connection detail between a footing and a pier element were also suggested. In order to investigate the seismic performance of the composite columns, several tests on concrete encased composite columns, which are prefabricated, were performed. Quasi-static tests were carried out and their performance was evaluated and compared with the results from the tests on CIP composite piers. In the case of precast piers, the end part of the pier needs to be carefully reinforced and related recommendations on details were derived.