• Title, Summary, Keyword: Analysis

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Comparative Study on Ground Response Analyses for Seismic Design of Geotechnical Structures (지반 구조물의 내진설계를 위한 지반응답해석 기법의 비교연구)

  • Hwang, Jae-Ik;Han, Jin-Tae;Cho, Jong-Seok;Kim, Myoung-Mo
    • Proceedings of the Korean Geotechical Society Conference
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    • pp.294-301
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    • 2005
  • Ground response analysis is one of the most important and most commonly encountered problems in geotechnical earthquake engineering. It is a prerequisite step for liquefaction assessment of saturated soil or the pseudo-static and dynamic analysis of geotechnical structures. A number of techniques have been developed for ground response analysis. In this study, ground response analyses were performed using the computer programs that are currently being used domestically. From these analyses, the analysis techniques applied to the programs were compared and analyzed. The results of ground response analyses were compared as follows: 1) 1-dimensional analysis vs. 2-dimensional analysis; 2) equivalent linear analysis vs. nonlinear analysis.

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Fatigue Analysis of Vehicle Chassis Component Considering Resonance Frequency (공진 주파수를 고려한 차량 섀시 부품의 피로해석)

  • Lee Sang Beom;Yim Hong Jae
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.13 no.6
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    • pp.94-101
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    • 2004
  • The purpose of this raper is to assess the benefits of frequency domain fatigue analysis and compare it with more conventional time domain techniques. The multi-body dynamic analysis, FE analysis and fatigue life prediction technique are applied for the frequency domain fatigue analysis. To obtain the dynamic load history used in the frequency domain fatigue analysis, the computer simulations running over typical road Profiles are carried out by utilizing vehicle dynamic model. The fatigue life estimation for the rear suspension system of small-sized passenger car is performed by using resonance durability analysis technique, and the estimation results are compared with the conventional quasi-static durability analysis results. For the pothole simulation, the percent changes, of the fatigue life between the two durability analysis techniques don't exceed 10%. But for the Belgian road simulation because of the resonance effect, the fatigue life using the resonance durability analysis technique are much smaller estimated than the quasi-static durability analysis results.

A Case Study on GNSS Based Deflection and Dynamic Characteristics Monitoring Analysis for SeoHae Bridge

  • Lee, Jae Kang;Kim, Jung Ok
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.35 no.5
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    • pp.389-404
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    • 2017
  • The main purpose of this presented investigation is to build up the BHMS based on GNSS. This proposed monitoring system can conduct the deflection and dynamic characteristics analysis by using only GNSS positioning solution. The general bridge monitoring system being operated recently is composed of a combination of various sensors that are able to conduct deflection monitoring and dynamic characteristics monitoring analysis at the same time. However, GNSS based BHMS has the unique procedure in terms of data analysis. In the other words, GNSS positioning solution is firstly applied to deflection monitoring analysis then, this deflection analysis can be sequentially reflected in the dynamic characteristics. Unfortunately, the adjustment result of GNSS positioning solution estimated through various options and conditions and the process of monitoring analysis has not been fulfilled systematically. This means that different results or analysis value are presented according to the methodology and officers. Most of researches have been focusing on deflection monitoring analysis and some investigation regarding to dynamic characteristics is recently introduced. Moreover, it is not still reported the systematic investigation with regards to proper filtering and analysis methodology. This study was carried out based on a large amount of data, from this, various variables not reported yet are actively considered. Therefore, specific software for both monitoring analysis have been developed.

A Rotordynamic and Stability Analysis of Process Gas Turbo-Compressor in accordance with API 617 Standard (API 617 규격에 의거한 프로세스 가스 터보압축기의 로터다이나믹 해석 및 안정성 검토)

  • Kim, Byung-Ok;Lee, An-Sung
    • The KSFM Journal of Fluid Machinery
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    • v.12 no.5
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    • pp.47-53
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    • 2009
  • A rotordynamic and detailed stability analysis in accordance with API 617 standard were performed with a turbo-compressor, which is one of key rotating machinery in refinery, petroleum, and power plants. The system is composed of rotor shaft, impeller, sleeve hub, balance drum, and coupling hub. The rotor system is supported by tilting pad bearings, which has 5 pads and pad on loading condition. The rotordynamic analysis specified by API 617 includes the critical speed map, mode shape analysis, Campbell diagram, unbalance response analysis, and stability analysis. In particular, the specifications of stability analysis consist of a Level 1 analysis that approximates the destabilizing effects of the labyrinth seals and aerodynamic excitations, and Level 2 analysis that includes a detailed labyrinth seal aerodynamic analysis. The results of a rotordynamic analysis and stability analysis can evaluate the operating compressor health and can be utilized as a guide of its maintenance, repair and trouble solution.

Site Response Analysis in Time Domain Using Finite Element (시간영역에서 유한요소법을 이용한 지진시의 지반응답해석)

  • You, Hee-Yong;Lee, Jae-Young;Park, Young-Tack
    • Journal of The Korean Society of Agricultural Engineers
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    • v.48 no.6
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    • pp.45-56
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    • 2006
  • The finite element method is a practical tool to compute the response of the irregularly layered soil deposit to the base-rock motions. The method is useful not only in estimating the interaction between the structure and the surrounding soil as a whole and the local behavior of the contacting area in detail, but also in predicting the resulting behavior of the superstructure affected by such soil-structure interactions. However, the computation of finite element analysis is marched in the time domain (TD), while the site response analysis has been carried out mostly in the frequency domain (FD) with equivalent linear analysis. This study is intended to compare the results of the TD and FD analysis with focus on the peak response accelerations and the predominant frequencies, and thus to evaluate the applicability and the validity of the finite element analysis in the site response analysis. The comparison shows that one can obtain the results very close to that of FD analysis, from the finite element analysis by including sufficiently large width of foundation in the model and further by applying partial mode superposition. The finite element analysis turned out to be well agreeing with FD analysis in their computed results of the peak acceleration and the acceleration response spectra, especially at the surface layer.

HisCoM-PCA: software for hierarchical structural component analysis for pathway analysis based using principal component analysis

  • Jiang, Nan;Lee, Sungyoung;Park, Taesung
    • Genomics & Informatics
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    • v.18 no.1
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    • pp.11.1-11.3
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    • 2020
  • In genome-wide association studies, pathway-based analysis has been widely performed to enhance interpretation of single-nucleotide polymorphism association results. We proposed a novel method of hierarchical structural component model (HisCoM) for pathway analysis of common variants (HisCoM for pathway analysis of common variants [HisCoM-PCA]) which was used to identify pathways associated with traits. HisCoM-PCA is based on principal component analysis (PCA) for dimensional reduction of single nucleotide polymorphisms in each gene, and the HisCoM for pathway analysis. In this study, we developed a HisCoM-PCA software for the hierarchical pathway analysis of common variants. HisCoM-PCA software has several features. Various principle component scores selection criteria in PCA step can be specified by users who want to summarize common variants at each gene-level by different threshold values. In addition, multiple public pathway databases and customized pathway information can be used to perform pathway analysis. We expect that HisCoM-PCA software will be useful for users to perform powerful pathway analysis.

A Study of the Vibration of an Axial Flow Pump through FSI Analysis Method (유체-구조 연성해석을 통한 축류펌프의 진동 연구)

  • Lee, Bo-Ram;Yun, Tae-Jong;Oh, Won-Bin;Lee, Chung-Woo;Kim, Hak Hyoung;Jeong, Yeong Jae;Kim, Ill-Soo
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.20 no.3
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    • pp.107-112
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    • 2021
  • Pressure, which is a dynamic characteristic of a floodgate, is predicted using an FSI analysis method. A fluid analysis model and a hydrology analysis model were used as analysis models. As a result of the analysis, we found that a warped model has smaller acceleration than a square model. Additionally, this numerical analysis technique was applied to the actual hydrology, and the analysis results were compared with the results of the vibration tests. As a result, we confirmed that there is a small difference between the results of the vibration tests and the results of the FSI analysis. Through this analysis, the applicability and reliability of the FSI analysis method were verified. We concluded that the pressure of a floodgate can be measured through an FSI analysis method.

Establishment and application of a qualitative real-time polymerase chain reaction method for detecting genetically modified papaya line 55-1 in papaya products (RT-PCR을 이용한 유전자변형파파야(55-1)검사법 확립 및 파파야가공식품의 적용 연구)

  • Kwon, Yu Jihn;Chung, So Young;Cho, Kyung Chul;Park, ji Eun;Koo, Eun Joo;Seo, Dong Hyuk;Kim, Eugene;Whang, Jehyun;Park, Seong Soo;Choi, Sun Ok;Lim, Chul Joo
    • Analytical Science and Technology
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    • v.28 no.2
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    • pp.117-124
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    • 2015
  • Genetically modified (GM) papaya line 55-1, which is resistant to PRSV infection, has been marketed globally. Prompt and sensitive protocols for specific detections are essential for the traceability of this line. Here, an event- and construct-specific real-time polymerase chain reaction (RT-PCR) method was established to detect 55-1. Qualitative detection was possible for fresh papaya fruit up to dilutions of 0.005% and 0.01% for the homozygous SunUp and heterozygous Rainbow cultivars, respectively, in non-GM papaya. The method was applied in the qualitative detection of 55-1 in eight types of commercially processed papaya products. Additionally, papaya products were monitored to distinguish GM papaya using the P35S and T-nos RT-PCR detection methods. As expected, detection capacity was improved via modified sample preparation and the established RT-PCR detection method. Taking these results together, it can be suggested that a suitable method for the extraction and purification of DNA from processed papaya products was established for the detection of GM papaya.

Improvement of Reliability of Static Execution Time Analysis Using Software Monitoring Technique (소프트웨어 감시 기법을 활용한 정적 실행시간 분석의 신뢰성 향상)

  • Kim, Yun-Kwan;Kim, Tae-Wan;Chang, Chun-Hyon
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.4
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    • pp.37-45
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    • 2010
  • A system which needs timely accuracy has to design and to verify correctly about execution-time for reliability. Accordingly, it is necessary for timing analysis tools, and much previous research worked. In timing analysis tool, there are two methods. One is a static analysis, and the other is a measurement based analysis. A static analysis is able to spend time less than a measurement based analysis method, but has low reliability of analysis result caused by hard to estimate time of I/O caused by various hardware. A measurement based analysis can be close analysis to real result, but it is hard to adapt to actual application, and spend a lot of time to get result of analysis. As such, this paper present a software monitoring architecture to supply reliability of static analysis process. In a presented architecture, it can select target as needed measurement through static analysis, and reuse result of measurement exist. Therefore, The architecture can reduce overload of time and performance for measurement, and improve the reliability which is the worst problem of static analysis.

Hydraulic Behavior and Characteristic Analysis by Steady & Unsteady Flow Analysis of Natural Stream (하도 합류부의 정류.부정류해석에 따른 수리학적 변화 특성 분석)

  • Ahn, Seung-Seop;Yim, Dong-Hee;Park, Ro-Sam;Kwak, Tae-Hwa
    • Journal of Environmental Science International
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    • v.17 no.9
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    • pp.957-968
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    • 2008
  • The purpose of this study is to analyze the characteristics of hydraulic behavior of the natural channel flow according to the temporal classification mode, and thus propose the hydraulic analysis method for future channel design. For analysis, the temporal flow characteristics of the channel section was divided into the steady flow and the unsteady flow. For hydraulic analysis, the HEC-RAS model, which is a one-dimensional numerical analysis model, and the SMS-RAM2 model, which is a two-dimensional model, were used and the factors used for analysis of hydraulic characteristics were flood elevation and flow rate. The flow state was analyzed on the basis of the one-dimensional steady flow and unsteady flow for review. In the unsteady flow analysis the flow rate changed by $(-)0.16%{\sim}(+)0.26%$, and the flood elevation varied by $(-)0.35%{\sim}(+)0.51%$ as compared to the values in the steady flow analysis. Given these results, in the one-dimensional flow analysis based on the unsteady flow the flood elevation and flow rate were greater than when the analysis was done on the basis of the steady flow. The flow state was analyzed on the basis of the two-dimensional steady flow and unsteady flow. In the unsteady flow analysis the flow rate varied by $(-)0.16%{\sim}(+)1.08%$, and the flood elevation changed by $(-)0.24%{\sim}(+)0.41%$ as compared to the values in the steady flow analysis. Given these analysis results, in the two dimensional flow analysis based on the unsteady flow, the flood elevation and flow rate were greater than when the analysis was done on the basis of the steady flow.