• 한국도로학회논문집
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• 제19권1호
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• pp.73-80
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• 2017

PURPOSES : This paper presents a comparison study between dynamic and static analyses of falling weight deflectometer (FWD) testing, which is a test used for evaluating layered material stiffness. METHODS: In this study, a forward model, based on nonlinear subgrade models, was developed via finite element analysis using ABAQUS. The subgrade material coefficients from granular and fine-grained soils were used to represent strong and weak subgrade stiffnesses, respectively. Furthermore, the nonlinearity in the analysis of multi-load FWD deflection measured from intact PCC slab was investigated using the deflection data obtained in this study. This pavement has a 14-inch-thick PCC slab over fine-grained soil. RESULTS: From case studies related to the nonlinearity of FWD analysis measured from intact PCC slab, a nonlinear subgrade model-based comparison study between the static and dynamic analyses of nondestructive FWD tests was shown to be effectively performed; this was achieved by investigating the primary difference in pavement responses between the static and dynamic analyses as based on the nonlinearity of soil model as well as the multi-load FWD deflection. CONCLUSIONS : In conclusion, a comparison between dynamic and static FEM analyses was conducted, as based on the FEM analysis performed on various pavement structures, in order to investigate the significance of the differences in pavement responses between the static and dynamic analyses.

• 디지털융복합연구
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• 제14권3호
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• pp.445-452
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• 2016

본 연구에서는 사람들이 흔히 경험하는 사회비교와 자기비교의 두 과정을 비교하여 살펴보고, 이와 관련된 이론들이 어떻게 응용될 수 있는지를 시사하고자 하였다. 이를 위해 사회비교이론에 해당하는 이론으로서 사회비교 이론과 자기평가유지모형을, 그리고 자기비교이론이라 할 수 있는 제어이론, 자기차이이론, 조절초점이론 및 시점비교이론을 차례로 개관하였다. 사회비교와 자기비교의 과정은 차이가 있지만, 이 두 비교 모두, 자기평가, 정서, 동기 및 행동에 영향을 미친다는 점에서는 유사하다. 사회비교와 자기비교에 관련된 연구들이 교육문제, 건강문제, 경제정의 및 대인관계 등에 대하여 지니는 응용적 함의들을 논의하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권6호
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• pp.2605-2610
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• 2012

Background: Studies investigating the association of 2R/3R polymorphism in the thymidylate synthase 5'-untranslated enhanced region (TSER) and colorectal cancer (CRC) risk have reported conflicting results. Thus, a meta-analysis was performed to summarize the data on the potential association. Methods: Pubmed, Embase and CBM databases were searched for all available studies. Links between the TSER 2R/3R polymorphism and CRC risk were estimated by odds ratios (ORs) with 95% confidence intervals (CIs). Results: Seven case-control studies with a total of 2723 cases and 4030 controls were included in this meta-analysis. The results showed that the 3R variant of TSER 2R/3R polymorphism contributes to CRC risk in two comparison models (OR 3R vs. 2R =1.10, 95%CI 1.02-1.18, P = 0.015; OR Homozygote comparison model = 1.22 1.04-1.43, 95%CI 1.04-1.43, P = 0.012). Subgroup analyses by ethnicity further demonstrated a contribution in Caucasians with three comparison models (OR 3R vs. 2R = 1.10, 95%CI 1.02-1.19, P = 0.015; OR Homozygote comparison model = 1.21, 95%CI 1.03-1.41, P = 0.019; OR Recessive comparison model = 1.18, 95%CI 1.05-1.33, P = 0.008). However, the association in the Asian population was still uncertain due to the limited data (all P values were more than 0.05). Conclusions: Our meta-analysis suggests that the 3R variant of Thymidylate synthase 5'-untranslated enhanced region 2R/3R polymorphism contributes to gastric cancer risk in the Caucasian population, while any association in Asian populations needs further study.

• 응용통계연구
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• 제19권2호
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• pp.231-240
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• 2006

일반적으로 쌍체 비교(paired comparison 또는 paired t test)가 효과적인 쌍으로의 구획을 통하여 소위 독립비교(group comparison)라고 일컫는 독립 이표본 t 검정(two-sample t test)보다 정밀한 결과를 제공하는 것으로 알려져 있다. 본 논문에서는 이와 같은 사실을 통계적으로 됫받침하기 위하여 두 방법의 정밀도를 보다 정량적으로 비교하였다. 독립 비교와 쌍체 비교가 각각 일원배치법과 이원배치법 (특히, 임의화 블록 설계법)의 특수한 경우이므로 각각에 상응하는 신뢰구간의 길이의 비로 정의된 비교 통계량은 분산분석의 통계량으로 표현된다. 다시 말해서, 이 통계량은 t 와 F 분포함수로 표현되므로 쉽게 독립비교와 쌍체비교의 정밀도를 비교할 수 있다. 실제로, 자주 쓰이는 유의수준에서는 쌍체표본 내에 구획 간의 유의한 변동이 있으면 쌍체비교가 독립비교보다 정밀할 가능성이 더 높다.

• Industrial Engineering and Management Systems
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• 제11권2호
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• pp.176-182
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• 2012

This paper presents a new approach to risk comparison in uncertain environment. Based on the uncertainty theory, some uncertain risk measures and risk comparison rules are proposed. Afterward the bridges are built between uncertain risk measures and risk comparison rules. Finally, several comparable examples are given.

• Nonlinear Functional Analysis and Applications
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• 제26권1호
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• pp.177-195
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• 2021

In this paper, we introduce the modification of a generalized (Ψ, L)-weak contraction and we prove some coincidence point results for self-mappings G, T and S, and some fixed point results for some maps by using a (c)-comparison function and a comparison function in the sense of a b-metric space.

• 대한전자공학회논문지
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• 제27권9호
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• pp.1351-1363
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• 1990

In this paper, a reliable control system structured with dual CPU modules and dual I/O modules is implemented as a means of achieving a highly reliable fault tolerant control system. For this, faults in the system modules are first examined, and a fault detection technique consisting of self diagnostic, comparison process, and exception processing is applied. Self diagnostic is used to locate which components in the modules have been failed, while comparison process is to cmpare control outputs computed by both CPU modules and protect the plant from malfunction by blocking failed control outputsin advance. Finally exception processing is used to determine the faults that are not detected immediately by the self diagnostic and comparison process, e.g. bus error processing when acknowledge signal for data transfer is not activeted in the I/O modules. Also reliability analysis is conducted for the discrete time Markov model with dual structure. It is shown quantitatively that the reliability is improved in the control system with dual structure in comparison with a system with single module structure.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.25-27
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• 2005

This paper deals with the comparison and analysis of brushless DC (BLDC) motor with radial and polar anisotropic plastic magnet. The open-circuit field distributions and back-emf for BLDC motor with polar plastic magnet are established analytically and the results are validated extensively by comparison with finite element (FE) analyses. On the basis of two dimensional (2-D) analytical solutions, this paper predicts open-circuit field characteristics according to design parameters and makes a comparison between BLDC motor with polar plastic magnet and it with radial plastic magnet in terms of required magnet volume and harmonic of air-gap flux density waveform.

• 한국신뢰성학회지:신뢰성응용연구
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• 제12권1호
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• pp.25-33
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• 2012

As to display products are made slim, the diameter of aluminum electrolytic capacitor is smaller and the length is longer to be fitted in. These small diameter and long length are pointed as the disadvantageous design factors of the capacitor's life cycle. So, the most electronic makers want to use proven capacitors (or well-known) to secure reliability of the electric products. In this study, we carried out the comparison analysis with two domestic capacitors and one foreign made capacitor. We designated separators, rubber breather and debris as the main factors that effect on the lifetime of capacitors. From the comparison results, we suggested the improvement points of the aluminum electrolytic capacitor.

• 한국지진공학회논문집
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• 제2권4호
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• pp.191-197
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• 1998

This paper described the dynamic characteristics of 20-story apartment buildings from the results of full-scale measurements and analysis. The natural frequencies and mode shapes are quantified by measuring and analyzing ambient vibrations of the structure and compared with the results from dynamic analysis. Comparison with computed mode shapes and frequencies shows good agreement with the experimental results. It proved that it is important to estimate coupling beam and soil parameters through a comparison of the measured results with calculated results.