• Title/Summary/Keyword: simplified methods of analysis

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Relationship between Intima Media Thickness of Common Carotid Artery and Sasang Constitution (사상체질과 경동맥 내중막 두께의 상관성 연구)

  • Han, Dong-Youn;Yu, Jun-Sang;Koh, Sang-Baek;Park, Jong-Ku
    • Journal of Sasang Constitutional Medicine
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    • v.23 no.2
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    • pp.218-229
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    • 2011
  • 1. Objectives: This study is to investigate the relationship between Intima Media Thickness(IMT) of common carotid artery and Sasang Constitution. 2. Methods: 839 persons, over 40 years old, participated in community-based cohort of Korea Genome and Epiedemiology Study (KOGES) in Wonju City and Pyeongchang City of South Korea from June 2006 to February 2008. The diagnosis of Common carotid Intima Media Thickness was evaluated by B Mode ultrasonography, cardiovascular risk factors were checked using questionnaire and blood samples. Constitution was verified by a Sasang constitution specialist according to the results of PSSC(Phonetic System for Sasang Constitution), facial photos and a simplified Sasang constitutional questionnaire. Multiple regression analysis and logistic regression analysis were performed with SPSS. 3. Results: There were significantly high values in waist circumference, fasting blood sugar, systolic blood pressure, diastolic blood pressure, triglyceride, HOMA-IR and hsCRP in Taeeumin and low in HDL-cholesterol and adiponectin in Taeeumin. There were significantly high value in Common Carotid Intima Media Thickness in Taeeumin. Age was the significant cardiovascular risk factor irrespective of Sasang constitution in all participants. There was a positive correlation between smoking and Soyangin in all participants and men. There were positive correlations between LDL-cholesterol, BMI and Taeeumin in all participants and men. There were positive correlations between hsCRP and Soeumin in all participants and men. There was significantly high odds ratio of Taeeumin over Soeumin in common carotid Intima Media Thickness. 4. Conclusions: Regimens on cardiovascular diseases should be considered according to Sasang constitution. There are more sensitive risk factor in each constitution; smoking in Soyangin, LDL-cholesterol and BMI in Taeeumin, hsCRP in Soeumin.

Estimation of Uncertainty on Greenhouse Gas Emission in the Agriculture Sector (농업분야 온실가스 배출량 산정의 불확도 추정 및 평가)

  • Bae, Yeon-Joung;Bae, Seung-Jong;Seo, Il-Hwan;Seo, Kyo;Lee, Jeong-Jae;Kim, Gun-Yeob
    • Journal of Korean Society of Rural Planning
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    • v.19 no.4
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    • pp.125-135
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    • 2013
  • Analysis and evaluation of uncertainty is adopting the advanced methodology among the methods for greenhouse gas emission assessment that was defined in GPS2000 (Good practice guideline 2000) and GPG-LULUCF (GPG Land Use, Land-Use Change and Forestry). In 2006 IPCC guideline, two approaches are suggested to explain the uncertainty for each section with a national net emission and a prediction value on uncertainty as follows; 1) Spread sheet calculation based on the error propagation algorithm that was simplified with some assumptions, and 2) Monte carlo simulation that can be utilized in general purposes. There are few researches on the agricultural field including greenhouse gas emission that is generated from livestock and cultivation lands due to lack of information for statistic data, emission coefficient, and complicated emission formula. The main objective of this study is to suggest an evaluation method for the uncertainty of greenhouse gas emission in agricultural field by means of intercomparison of the prediction value on uncertainties which were estimated by spread sheet calculation and monte carlo simulation. A statistic analysis for probability density function for uncertainty of emission rate was carried out by targeting livestock intestinal fermentation, excrements treatment, and direct/indirect emission from agricultural lands and rice cultivation. It was suggested to minimize uncertainty by means of extraction of emission coefficient according to each targeting section.

Dynamic behavior of H-shape tall building subjected to wind loading computed by stochastic and CFD methodologies

  • Lucas Willian Aguiar Mattias;Joao Elias Abdalla Filho
    • Wind and Structures
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    • v.37 no.3
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    • pp.229-243
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    • 2023
  • This study analyzes the response of a tall building with an H-shaped cross-section when subjected to wind loading generated by the same H-shape. As normative standards usually adopt regular geometries for determining the wind loading, this paper shows unpublished results which compares results of the dynamic response of H-shaped buildings with the response of simplified section buildings. Computational Fluid Dynamics (CFD) is employed to determine the steady wind load on the H-shaped building. The CFD models are validated by comparison with wind tunnel test data for the k-ε and k-ω models of turbulence. Transient wind loading is determined using the Synthetic Wind Method. A new methodology is presented that combines Stochastic and CFD methods. In addition, time-history dynamic structural analysis is performed using the HHT method for a period of 60 seconds on finite element models. First, the along-wind response is studied for wind speed variations. The wind speeds of 28, 36, 42, and 50 m/s at 0° case are considered. Subsequently, the dynamic response of the building is studied for wind loads at 0°, 45°, and 90° with a wind speed of 42 m/s, which approximates the point of resonance between gusts of wind and the structure. The response values associated with the first two directions for the H-shaped building are smaller than those for the R-shaped (Equivalent Rectangular Shape) one. However, the displacements of the H-shaped building associated with the latter wind load are larger.

Dimension Reduction of Solid Models by Mid-Surface Generation

  • Sheen, Dong-Pyoung;Son, Tae-Geun;Ryu, Cheol-Ho;Lee, Sang-Hun;Lee, Kun-Woo
    • International Journal of CAD/CAM
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    • v.7 no.1
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    • pp.71-80
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    • 2007
  • Recently, feature-based solid modeling systems have been widely used in product design. However, for engineering analysis of a product model, an ed CAD model composed of mid-surfaces is desirable for conditions in which the ed model does not affect analysis result seriously. To meet this requirement, a variety of solid ion methods such as MAT (medial axis transformation) have been proposed to provide an ed CAE model from a solid design model. The algorithm of the MAT approach can be applied to any complicated solid model. However, additional work to trim and extend some parts of the result is required to obtain a practically useful CAE model because the inscribed sphere used in the MAT method generates insufficient surfaces with branches. On the other hand, the mid-surface ion approach supports a practical method for generating a two-dimensional ed model, even though it has difficulties in creating a mid-surface from some complicated parts. In this paper, we propose a dimension reduction approach on solid models based on the midsurface abstraction approach. This approach simplifies the solid model by abbreviating or removing trivial features first such as the fillet, mounting, or protrusion. The geometry of each face is replaced with mid-patches from the simplified model, and then unnecessary topological entities are deleted to generate a clean ed model. Also, additional work, such as extending and stitching mid-patches, completes the generation of a mid-surface model from the patches.

Development of Modified Disturbed State Concept Model for Liquefaction Analysis (액상화 해석을 위한 수정교란상태개념 모델 개발)

  • Park, Keun-Bo;Choi, Jae-Soon;Park, Inn-Joon;Kim, Ki-Poong;Kim, Soo-Il
    • Journal of the Korean Geotechnical Society
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    • v.24 no.3
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    • pp.35-51
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    • 2008
  • In this paper, the application of the DSC model to the analysis of liquefaction potential is examined through experimental and analytical investigations. For more realistic description of dynamic responses of saturated sands, the DSC model was modified based on the dynamic effective stress path and excess pore pressure development. Both static and cyclic undrained triaxial tests were performed for sands with different relative densities and confining stresses. Based on test results, a classification of liquefaction phases in terms of the dynamic effective stress path and the excess pore pressure development was proposed and adopted into the modified DSC model. The proposed methods using the original and modified DSC models were compared with examples with different relative densities and confining stresses. Based on the comparisons between the predicted results using the original and modified DSC models and experimental data, the parameters required to define the model were simplified. It was also found that modified model more accurately simulate initial liquefaction and dynamic responses of soil under cyclic undrained triaxial tests.

Metabolic Syndrome and Sasang Constitution in Cohort Study (사상체질과 대사증후군 유발에 관한 코호트 연구)

  • Yun, Woo-Yeong;Yu, Jun-Sang;Park, Jong-Ku
    • Journal of Sasang Constitutional Medicine
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    • v.25 no.1
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    • pp.1-13
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    • 2013
  • Objectives This study is to investigate the related factors to contribute the metabolic syndrome according to Sasang Constitution. Methods Nine hundred twenty six persons out of 1774 persons, over 40 years old, participated in community-based cohort in Wonju City of South Korea from June 2006 to August 2009. The diagnosis of metabolic syndrome was carried out by NCEP-ATP III(National Cholesterol Education Program in Adult Treatment Panel III) and Asian Pacific Criteria for abdominal obesity. The related factors were checked using questionnaire and blood samples. Sasang Constitution was verified by a Sasang Constitution specialist using the results of PSSC(Phonetic System for Sasang Constitution), facial pictures and simplified Sasang Constitutional questionnaires. Metabolic syndrome incidence rate according to Sasang Constitution and binary logistic regression analysis were performed with SPSS 19.0. Results Metabolic syndrome incidence rate was 30.3% and the majority of newly categorized as metabolic syndrome was Taeeumin(40.7%). There were significant risk factors like systolic blood pressure, fasting blood sugar, triglyceride and female and a significant defense factor like HDL-cholesterol. In terms of constitutional view, there were significant risk factors like waist circumference, systolic blood pressure, triglyceride in Soyangin, female, waist circumference, systolic blood pressure, fasting blood sugar, triglyceride in Taeeumin, female, waist circumference, systolic blood pressure, triglyceride in Soeumin. And there was a significant defense factor like HDL-cholesterol in only Taeeumin. Conclusions Regimens on metabolic syndrome were considered to be changed according to Sasang Constitution. Taeeumin female and Soeumin female should be cautious of body weight and metabolic syndrome when elderly. There are more cautious risk factors in each constitution; systolic blood pressure and triglyceride in Soyangin and fasting blood sugar and serum lipids levels in Soeumin and Taeeumin.

Optimal Design of Reinforced Concrete Frames using Sensitivity Analysis (설계민감도를 이용한 철근콘크리트 뼈대구조의 최적화)

  • Byun, Keun Joo;Choi, Hong Shik
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.9 no.1
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    • pp.33-40
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    • 1989
  • In the design of reinforced concrete framed structures, which consist of various design variables, the objective and the constraint functions are formulated in complicated forms. Usually iterative methods have been used to optimize the design variables. In this paper, multilevel formulation is adopted, and design variables are selected in reduced numbers at each level, to reduce the iterative cycle and to accelerate the convergence rate. At level 1, elastic analysis is performed to get the upper and lower bounds of the redistributed design moments due to inelastic behavior of the frame. Then the design moments are taken as design variables and optimized at level 2, and the sizing variables are optimized at level 3. The optimization of redistributed moments is performed using the design sensitivity obtained at the level 2, and force approximation technique is used to reflect the variation of design variables in the lower level to the upper level. The design variables are selected in reduced numbers at each level, and the optimization formulation is simplified effectively. A cost function is taken as the objective function, and the constraints of the stress of the structures are derived from BSI CP 110 following limit state theory. Numerical examples are included to prove the effectiveness of the developed algorithm.

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Flexural strength and microstructure of two lithium disilicate glass ceramics for CAD/CAM restoration in the dental clinic

  • Kang, Suk-Ho;Chang, Juhea;Son, Ho-Hyun
    • Restorative Dentistry and Endodontics
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    • v.38 no.3
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    • pp.134-140
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    • 2013
  • Objectives: There has been a growing interest in glass ceramic systems with good esthetics, high fracture resistance and bonding durability, and simplified fabrication techniques using CAD/CAM. The aim of this study is to compare flexural strength before and after heat treatment of two lithium disilicate CAD/CAM blocks, IPS e.max CAD (Ivoclar Vivadent) and Rosetta SM (Hass), and to observe their crystalline structures. Materials and Methods: Biaxial flexural strength was tested according to ISO 6872 with 20 disc form specimens sliced from each block before and after heat treatment. Also, the crystalline structures were observed using field-emission scanning microscopy (FE-SEM, Hitachi) and x-ray diffraction (XRD, Rigaku) analysis. The mean values of the biaxial flexural strength were analyzed by the Mann-Whitney U test at a significance level of p = 0.05. Results: There were no statistically significant differences in flexural strength between IPS e.max CAD and Rosetta SM either before heat treatment or after heat treatment. For both ceramics, the initial flexural strength greatly increased after heat treatment, with significant differences (p < 0.05). The FE-SEM images presented similar patterns of crystalline structure in the two ceramics. In the XRD analysis, they also had similar patterns, presenting high peak positions corresponding to the standard lithium metasilicate and lithium disilicate at each stage of heat treatment. Conclusions: IPS e.max CAD and Rosetta SM showed no significant differences in flexural strength. They had a similar crystalline pattern and molecular composition.

A Study of Double Dark Photons Produced by Lepton Colliders using High Performance Computing

  • Park, Kihong;Kim, Kyungho;Cho, Kihyeon
    • Journal of Astronomy and Space Sciences
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    • v.39 no.1
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    • pp.1-10
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    • 2022
  • The universe is thought to be filled with not only Standard Model (SM) matters but also dark matters. Dark matter is thought to play a major role in its construction. However, the identity of dark matter is as yet unknown, with various search methods from astrophysical observartion to particle collider experiments. Because of the cross-section that is a thousand times smaller than SM particles, dark matter research requires a large amount of data processing. Therefore, optimization and parallelization in High Performance Computing is required. Dark matter in hypothetical hidden sector is though to be connected to dark photons which carries forces similar to photons in electromagnetism. In the recent analysis, it was studied using the decays of a dark photon at collider experiments. Based on this, we studies double dark photon decays at lepton colliders. The signal channels are e+e- → A'A' and e+e- → A'A'γ where dark photon A' decays dimuon. These signal channels are based on the theory that dark photons only decay into heavily charged leptons, which can explain the muon magnetic momentum anomaly. We scanned the cross-section according to the dark photon mass in experiments. MadGraph5 was used to generate events based on a simplified model. Additionally, to get the maximum expected number of events for the double dark photon channel, the detector efficiency for several center of mass (CM) energy were studied using Delphes and MadAnalysis5 for performance comparison. The results of this study will contribute to the search for double dark photon channels at lepton colliders.

AN ANALYSIS OF TECHNICAL SECURITY CONTROL REQUIREMENTS FOR DIGITAL I&C SYSTEMS IN NUCLEAR POWER PLANTS

  • Song, Jae-Gu;Lee, Jung-Woon;Park, Gee-Yong;Kwon, Kee-Choon;Lee, Dong-Young;Lee, Cheol-Kwon
    • Nuclear Engineering and Technology
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    • v.45 no.5
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    • pp.637-652
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    • 2013
  • Instrumentation and control systems in nuclear power plants have been digitalized for the purpose of maintenance and precise operation. This digitalization, however, brings out issues related to cyber security. In the most recent past, international standard organizations, regulatory institutes, and research institutes have performed a number of studies addressing these systems cyber security.. In order to provide information helpful to the system designers in their application of cyber security for the systems, this paper presents methods and considerations to define attack vectors in a target system, to review and select the requirements in the Regulatory Guide 5.71, and to integrate the results to identify applicable technical security control requirements. In this study, attack vectors are analyzed through the vulnerability analyses and penetration tests with a simplified safety system, and the elements of critical digital assets acting as attack vectors are identified. Among the security control requirements listed in Appendices B and C to Regulatory Guide 5.71, those that should be implemented into the systems are selected and classified in groups of technical security control requirements using the results of the attack vector analysis. For the attack vector elements of critical digital assets, all the technical security control requirements are evaluated to determine whether they are applicable and effective, and considerations in this evaluation are also discussed. The technical security control requirements in three important categories of access control, monitoring and logging, and encryption are derived and grouped according to the elements of attack vectors as results for the sample safety system.