• 제목/요약/키워드: Cross-comparison

검색결과 1,609건 처리시간 0.046초

Effect of cross-beam on stresses revealed in orthotropic steel bridges

  • Fettahoglu, Abdullah
    • Steel and Composite Structures
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    • 제18권1호
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    • pp.149-163
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    • 2015
  • Orthotropic steel highway bridges exist almost everywhere in world, especially in Europe. The design of these bridges started very early in 20th century and ended with a conventional orthotropic steel bridge structure, which is today specified in DIN FB 103. These bridges were mostly built in 1960's and exhibit damages in steel structural parts. The primary reason of these damages is the high pressure that is induced by wheel- loads and therefore damages develop especially in heavy traffic lanes. Constructive rules are supplied by standards to avoid damages in orthotropic steel structural parts. These rules are first given in detail in the standard DIN 18809 (Steel highway- and pedestrian bridges- design, construction, fabrication) and then in DIN- FB 103 (Steel bridges). Bridges built in the past are today subject to heavier wheel loads and the frequency of loading is also increased. Because the vehicles produced today in 21st century are heavier than before and more people have vehicle in comparison with 20th century. Therefore dimensioning or strengthening of orthotropic steel bridges by using stiffer dimensions and shorter spans is an essence. In the scope of this study the complex geometry of conventional steel orthotropic bridge is generated by FE-Program and the effects of cross beam web thickness and cross beam span on steel bridge are assessed by means of a parameter study. Consequently, dimensional and constructional recommendations in association with cross beam thickness and span will be given by this study.

한·중 크로스오버 쇼퍼들의 모바일 앱 충성도에 대한 탐색적 연구 (Mobile app Loyalty of Cross-over Shoppers: A Comparison of Korean and Chinese)

  • 박은주;구진;박신영
    • 한국의류산업학회지
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    • 제20권3호
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    • pp.293-303
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    • 2018
  • Since 2009, consumers could access a new shopping channel called 'mobile shopping' with the generalization of smartphones. Mobile shopping (based on wireless communication technology), emphasizes convenience differentiated from internet shopping. A recent report introduced fashion products as powerful global drivers for mobile shopping sales. Korea and China have the highest percentage of consumer mobile shopping experiences compared to other countries. This study investigates the effects of cross-over shopping orientation, perception of app attributes, and flow on app loyalty that compared Korean and Chinese consumers. We obtained 652 usable questionnaires from two local college students; subsequently, data were analyzed by using factor analysis, Cronbach's alpha, and regression analysis using SPSS 21.0 Package. The study results showed that the cross-over shopping orientation affected perception of app attributes that included Review/Information, Design, Response and Product. Product only affected Flow, which reflected a high similarity between Korean and Chinese consumers. However, Korean and Chinese consumers showed remarkable differences in the factors related to app loyalty. Therefore, the results indicate that retailers of fashion products have developed strategies to improve mobile sales and increase the app loyalty of cross-over shopping orientation consumers.

레이더 시스템에서 레이더 단면적에 따른 탐지 거리 추정을 위한 코히런트 집적과 비 코히런트 집적에 대한 비교 (A Comparison on Coherent Integration and Non-coherent Integration to Estimate Detection Range about Radar Cross Section in Radar System)

  • 함성민;가관우;이관형
    • 한국정보전자통신기술학회논문지
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    • 제7권2호
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    • pp.100-105
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    • 2014
  • 본 논문에서는 레이더 시스템에서 탐지 거리 추정에 영향을 미치는 레이더 단면적의 크기에 대한 집적 방식을 비교 분석한다. 본 논문에서는 레이더 단면적의 크기에 따라 크기가 작을 경우 스웰링 케이스 1, 클 경우에는 스웰링 케이스 3의 탐지 확률을 레이더 방정식에 적용하여 탐지 거리를 추정하였다. 모의실험을 통해서 스웰링 케이스의 차이에 따른 코히런트 집적과 비 코히런트 방식을 비교 분석하였다. 모의실험을 통해서, 비 코히런트 집적 방식이 추정 거리가 가장 우수하였고 코히런트 집적 방식은 스웰링 케이스를 적용한 탐지 거리 추정에 적합하지 않음을 알 수 있었다.

Force-deformation behaviour modelling of cracked reinforced concrete by EXCEL spreadsheets

  • Lam, Nelson;Wilson, John;Lumantarna, Elisa
    • Computers and Concrete
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    • 제8권1호
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    • pp.43-57
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    • 2011
  • Force-deformation modelling of cracked reinforced concrete is essential for a displacement-based seismic assessment of structures and can be achieved by fibre-element analysis of the cross-section of the major lateral resisting elements. The non-linear moment curvature relationship obtained from fibre-element analysis takes into account the significant effects of axial pre-compression and contributions by the longitudinal reinforcement. Whilst some specialised analysis packages possess the capability of incorporating fibre-elements into the modelling (e.g., RESPONSE 2000), implementation of the analysis on EXCEL is illustrated in this paper. The outcome of the analysis is the moment-curvature relationship of the wall cross-section, curvature at yield and at damage control limit states specified by the user. Few software platforms can compete with EXCEL in terms of its transparencies, versatility and familiarity to the computer users. The program has the capability of handling arbitrary cross-sections that are without an axis of symmetry. Application of the program is illustrated with examples of typical cross-sections of structural walls. The calculated limiting curvature for the considered cross-sections were used to construct displacement profiles up the height of the wall for comparison with the seismically induced displacement demand.

에어컨 용 횡단류 홴의 특정 주파수 소음 성분의 저감 대책에 관한 연구 -날개의 랜덤 배열과 경사진 스태빌라이저에 대한 연구- (A Study on the Reduction of Discrete Frequency Tones of a Cross-Flow Fan of Air-Conditioners -Studies on the Random Distribution of Fan Blades and the Skewed Stabilizers-)

  • 구형모
    • 소음진동
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    • 제8권5호
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    • pp.870-878
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    • 1998
  • The cross-flow fan which constitutes a fan-duct system with a stabilizer and a scroll casing is widely used in many air-ventilating and air-conditioning devices. Its ooperating points of high efficiency and loading conditions frequently induce a annoying sharp tonal component of discrete frequency on the noise spectrum, which is open called as a BPF(Blade-Passing-Frequency) noise and degrades the sound quality of the devices. this BPF tone has been one of the defects of the cross-flow fan. This study proposes two methods in order to reduce this tonal noise component, which are the random distributions of the fan blades and the skewed shapes of the stabilizer. The proposed methods are verified by a simple analytical model and are applied in manufacturing the cross-flow fan and the stabilizer samples. Some experiments are carried out to verify the reduction capability of BPF tones of above two schemes and the experimental results are analyzed. The comparison between two method is also carried out.

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The Reaction Probability and the Reaction Cross-section of N + O2→ NO + O Reaction Computed by the 6th-order Explicit Symplectic Algorithm

  • He, Jianfeng;Li, Jing
    • Bulletin of the Korean Chemical Society
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    • 제27권12호
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    • pp.1976-1980
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    • 2006
  • We have calculated the reaction probability and the reaction cross-section of the $N(^4S)+O_2(X^3\sum_{g}^{-})\;\rightarrow\;NO(X^2\Pi)+O(^3P)$ reaction by the quasiclassical trajectory method with the 6th-order explicit symplectic algorithm, based on a new ground potential energy surface. The advantage of the 6th-order explicit symplectic algorithm, conserving both the total energy and the total angular momentum of the reaction system during the numerical integration of canonical equations, has firstly analyzed in this work, which make the calculation of the reaction probability more reliable. The variation of the reaction probability with the impact parameter and the influence of the relative translational energy on the reaction cross-section of the reaction have been discussed in detail. And the fact is found by the comparison that the reaction probability and the reaction cross-section of the reaction estimated in this work are more reasonable than the theoretical ones determined by Gilibert et al.

생강 전분과 옥수수 가교 전분의 이화학적 성질 비교 (Comparison of Some Physicochemical Properties of Ginger Root and Cross-linked Corn Starches)

  • 허준;김성곤
    • 한국식품과학회지
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    • 제16권2호
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    • pp.201-205
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    • 1984
  • 생강전분의 몇 가지 물리화학적 성질을 옥수수 가교 전분과 비교 검토하였다. 생강전분은 아밀로스 함량이 23.5%, 물결합 능력이 99.1%이었고 B형의 X-ray 회절도를 보였다. 생강 전분의 광투과도는 $70^{\circ}C$ 이후에 증가하였고 옥수수 가교 전분의 swelling power와 용해도는 $90^{\circ}C$까지 아주 낮은 값을 보였으며, 알카리에 대하여도 안정하였다. 아밀로그라피에 의한 생강전분 (7%)의 초기 호화온도는 $81.5^{\circ}C$ 이었고, 옥수수 가교전분과 같이 안정한 Paste를 보였다.

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Tri-training algorithm based on cross entropy and K-nearest neighbors for network intrusion detection

  • Zhao, Jia;Li, Song;Wu, Runxiu;Zhang, Yiying;Zhang, Bo;Han, Longzhe
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제16권12호
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    • pp.3889-3903
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    • 2022
  • To address the problem of low detection accuracy due to training noise caused by mislabeling when Tri-training for network intrusion detection (NID), we propose a Tri-training algorithm based on cross entropy and K-nearest neighbors (TCK) for network intrusion detection. The proposed algorithm uses cross-entropy to replace the classification error rate to better identify the difference between the practical and predicted distributions of the model and reduce the prediction bias of mislabeled data to unlabeled data; K-nearest neighbors are used to remove the mislabeled data and reduce the number of mislabeled data. In order to verify the effectiveness of the algorithm proposed in this paper, experiments were conducted on 12 UCI datasets and NSL-KDD network intrusion datasets, and four indexes including accuracy, recall, F-measure and precision were used for comparison. The experimental results revealed that the TCK has superior performance than the conventional Tri-training algorithms and the Tri-training algorithms using only cross-entropy or K-nearest neighbor strategy.

MGGC2.0: A preprocessing code for the multi-group cross section of the fast reactor with ultrafine group library

  • Kui Hu;Xubo Ma;Teng Zhang;Xuan Ma;Zifeng Huang;Yixue Chen
    • Nuclear Engineering and Technology
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    • 제55권8호
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    • pp.2785-2796
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    • 2023
  • How to generate the precise broad group cross section is important for the fast reactor design. In this study, a fast reactor multi-group cross-section generation code MGGC2.0 are developed in-house for processing ultrafine group MATXS format library. Validation and verification are performed for MGGC2.0 code by applying the benchmarks of ICSBEP handbook, and the results of MGGC2.0 agree well with that of MCNP. The consistent PN method with critical buckling search is in good agreement that condensed with TWODANT flux and flux moment for the inner core and outer core region. For the radial blanket and reflector, two region approximation method has been applied in MGGC2.0 by using collision Probability Method neutron flux solver. The RBEC-M benchmark was used to verify the power distribution calculation, and the relative error of power distribution comparison with the reference are less than 0.8% in the fuel region and the maximum relative error is 5.58% in the reflector region. Therefore, the precise broad cross section can be generated by MGGC2.0 for fast reactor.

McCARD/MIG stochastic sampling calculations for nuclear cross section sensitivity and uncertainty analysis

  • Ho Jin Park
    • Nuclear Engineering and Technology
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    • 제54권11호
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    • pp.4272-4279
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    • 2022
  • In this study, a cross section stochastic sampling (S.S.) capability is implemented into both the McCARD continuous energy Monte Carlo code and MIG multiple-correlated data sampling code. The ENDF/B-VII.1 covariance data based 30 group cross section sets and the SCALE6 covariance data based 44 group cross section sets are sampled by the MIG code. Through various uncertainty quantification (UQ) benchmark calculations, the McCARD/MIG results are verified to be consistent with the McCARD stand-alone sensitivity/uncertainty (S/U) results and the XSUSA S.S. results. UQ analyses for Three Mile Island Unit 1, Peach Bottom Unit 2, and Kozloduy-6 fuel pin problems are conducted to provide the uncertainties of keff and microscopic and macroscopic cross sections by the McCARD/MIG code system. Moreover, the SNU S/U formulations for uncertainty propagation in a MC depletion analysis are validated through a comparison with the McCARD/MIG S.S. results for the UAM Exercise I-1b burnup benchmark. It is therefore concluded that the SNU formulation based on the S/U method has the capability to accurately estimate the uncertainty propagation in a MC depletion analysis.