• Title/Summary/Keyword: FA(factor Analysis)

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Unsupervised one-class classification for condition assessment of bridge cables using Bayesian factor analysis

  • Wang, Xiaoyou;Li, Lingfang;Tian, Wei;Du, Yao;Hou, Rongrong;Xia, Yong
    • Smart Structures and Systems
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    • v.29 no.1
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    • pp.41-51
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    • 2022
  • Cables are critical components of cable-stayed bridges. A structural health monitoring system provides real-time cable tension recording for cable health monitoring. However, the measurement data involve multiple sources of variability, i.e., varying environmental and operational factors, which increase the complexity of cable condition monitoring. In this study, a one-class classification method is developed for cable condition assessment using Bayesian factor analysis (FA). The single-peaked vehicle-induced cable tension is assumed to be relevant to vehicle positions and weights. The Bayesian FA is adopted to establish the correlation model between cable tensions and vehicles. Vehicle weights are assumed to be latent variables and the influences of different transverse positions are quantified by coefficient parameters. The Bayesian theorem is employed to estimate the parameters and variables automatically, and the damage index is defined on the basis of the well-trained model. The proposed method is applied to one cable-stayed bridge for cable damage detection. Significant deviations of the damage indices of Cable SJS11 were observed, indicating a damaged condition in 2011. This study develops a novel method to evaluate the health condition of individual cable using the FA in the Bayesian framework. Only vehicle-induced cable tensions are used and there is no need to monitor the vehicles. The entire process, including the data pre-processing, model training and damage index calculation of one cable, takes only 35 s, which is highly efficient.

Application of multivariate statistics towards the geochemical evaluation of fluoride enrichment in groundwater at Shilabati river bank, West Bengal, India

  • Ghosh, Arghya;Mondal, Sandip
    • Environmental Engineering Research
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    • v.24 no.2
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    • pp.279-288
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    • 2019
  • To obtain insightful knowledge of geochemical process controlling fluoride enrichment in groundwater of the villages near Shilabati river bank, West Bengal, India, multivariate statistical techniques were applied to a subgroup of the dataset generated from major ion analysis of groundwater samples. Water quality analysis of major ion chemistry revealed elevated levels of fluoride concentration in groundwater. Factor analysis (FA) of fifteen hydrochemical parameters demonstrated that fluoride occurrence was due to the weathering and dissolution of fluoride-bearing minerals in the aquifer. A strong positive loading (> 0.75) of fluoride with pH and bicarbonate for FA indicates an alkaline dominated environment responsible for leaching of fluoride from the source material. Mineralogical analysis of soli sediment exhibits the presence of fluoride-bearing minerals in underground geology. Hierarchical cluster analysis (HCA) was carried out to isolate the sampling sites according to groundwater quality. With HCA the sampling sites were isolated into three clusters. The occurrence of abundant fluoride in the higher elevated area of the observed three different clusters revealed that there was more contact opportunity of recharging water with the minerals present in the aquifer during infiltration through the vadose zone.

A Classification Method Using Data Reduction

  • Uhm, Daiho;Jun, Sung-Hae;Lee, Seung-Joo
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.12 no.1
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    • pp.1-5
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    • 2012
  • Data reduction has been used widely in data mining for convenient analysis. Principal component analysis (PCA) and factor analysis (FA) methods are popular techniques. The PCA and FA reduce the number of variables to avoid the curse of dimensionality. The curse of dimensionality is to increase the computing time exponentially in proportion to the number of variables. So, many methods have been published for dimension reduction. Also, data augmentation is another approach to analyze data efficiently. Support vector machine (SVM) algorithm is a representative technique for dimension augmentation. The SVM maps original data to a feature space with high dimension to get the optimal decision plane. Both data reduction and augmentation have been used to solve diverse problems in data analysis. In this paper, we compare the strengths and weaknesses of dimension reduction and augmentation for classification and propose a classification method using data reduction for classification. We will carry out experiments for comparative studies to verify the performance of this research.

Prediction of dynamic behavior of full-scale slope based on the reduced scale 1 g shaking table test

  • Jin, Yong;Kim, Daehyeon;Jeong, Sugeun;Park, Kyungho
    • Geomechanics and Engineering
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    • v.31 no.4
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    • pp.423-437
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    • 2022
  • The objective of the study is to evaluate the feasibility of the dynamic behavior of slope through both 1 g shaking table test and numerical analysis. Accelerometers were installed in the slope model with different types of seismic waves. The numerical analysis (ABAQUS and DEEPSOIL) was used to simulate 1 g shaking table test at infinite boundary. Similar Acceleration-time history, Spectral acceleration (SA) and Spectral acceleration amplification factor (Fa) were obtained, which verified the feasibility of modeling using ABAQUS and DEEPSOIL under the same size. The influence of the size (1, 2, 5, 10 and 20 times larger than that used in the 1 g shaking table test) of the model used in the numerical analysis were extensively investigated. According to the similitude law, ABAQUS was used to analyze the dynamic behavior of large-scale slope model. The 5% Damping Spectral acceleration (SA) and Spectral acceleration amplification factor (Fa) at the same proportional positions were compared. Based on the comparison of numerical analyses and 1 g shaking table tests, it was found that the 1 g shaking table test result can be utilized to predict the dynamic behavior of the real scale slope through numerical analysis.

Analysis of Permeability Characteristics for Fly Ash Concrete According to Aggregate Size and Mixing Ratio (골재크기와 배합비에 따른 플라이애시 콘크리트의 투기특성 분석)

  • Eun-A Seo;Do-Gyeum Kim;Chul-Woo Jung;Ho-Jae Lee
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.11 no.4
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    • pp.400-406
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    • 2023
  • In this study, the relationship between the material properties and air permeability characteristics was examined, an experimental method to analyze the air permeability characteristics was presented, and experimental results were derived. The effects of compressive strength and apparent density of hardened concrete on air permeability characteristics were evaluated experimentally. Focusing on the mix proportions used in nuclear power plant concrete structures, concrete test specimens were manufactured and air permeability characteristics were measured according to changes in binder, maximum aggregate size, and water-binder ratio. The apparent density was over 2,400 kg/m3 for the OPC mix and the FA-35 mix, and the air permeability for both mixes were low, in the range of 0.1-0.2 L/min. On the other hand, in the case of the combination of FA-40, FA-45, and FA-M, the apparent density was measured to be less than 2,400 kg/m3 and the air permeability was measured to be more than 0.3 L/min, experimentally verifying that the apparent density is an important factor in air permeability characteristics.

Water Extracts of Anthriscus sylvestris Leaf induces Apoptosis in FaDu Human Hypopharynx Squamous Carcinoma Cells

  • Yang, Jung Eun;Lee, Seul Ah;Moon, Sung Min;Han, Seul Hee;Choi, Yun Hee;Kim, Su-Gwan;Kim, Do Kyung;Park, Bo-Ram;Kim, Chun Sung
    • International Journal of Oral Biology
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    • v.42 no.2
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    • pp.47-54
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    • 2017
  • Anthriscus sylvestris (L.) Hoffm. is a perennial herb found widely distributed in various regions of Korea, Europe, and New Zealand. The root of A. sylvestris have been extensively used in the treatment for antitussive, antipyretic, cough remedy in Oriental medicine, but the physiologically active function of the leaf of A. sylvestris is as yet unknown. In this study, we investigated the anti-cancer activity and the mechanism of cell death of water extracts of leaf of Anthriscus sylvestris (WELAS), on human FaDu hypopharyngeal squamous carcinoma cells. Our data showed that WELAS treatment inhibited cell viability in a concentration- and time-dependent manner. In addition, the treatment of WELAS markedly induced apoptosis in FaDu cells, as determined by the viability assay, DAPI stain and FACS analysis. WELAS also increased the proteolytic cleavage of procaspase-3, -9 and PARP (poly(ADP-ribose) polymerase). In addition, exposure to WELAS decreased the expression of Bcl-2 (an anti-apoptotic factor), but increased the expression of Bax (a pro-apoptotic factor), suggesting that mitochondria-dependent apoptotic pathways are mediated in WELAS-induced apoptosis. Taken together, these results indicate that water extracts of leaf of A. sylvestris inhibits cell growth and induces apoptosis via the mitochondrial-dependent apoptotic pathway in FaDu human hypopharyngeal squamous carcinoma cells. Therefore, we propose that the water extracts of leaf of A. sylvestris is a novel chemotherapeutic drug, having growth inhibitory properties and induction of apoptosis in human oral cancer cells.

Latex of Ficus carica L. Induces Apoptosis Through Caspase and Bcl-2 Family in FaDu Human Hypopharynx Squamous Carcinoma Cells

  • Shin, Bo Su;Lee, Seul Ah;Moon, Sung Min;Han, Seul Hee;Hwang, Eun Ju;Kim, Su-Gwan;Kim, Do Kyung;Kim, Jin-Soo;Park, Bo-Ram;Kim, Chun Sung
    • International Journal of Oral Biology
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    • v.42 no.4
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    • pp.183-190
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    • 2017
  • Ficus carica L. (common fig), one of the first plants cultivated by humans, originated in the Mediterranean basin and currently grows worldwide, including southwest Asia and South Korea. It has been used as a traditional medicine for treatment of metabolic, cardiovascular, and respiratory diseases as well as hemorrhoids and skin infections. Its pharmacological properties have recently been studied in detail, but research on the anti-cancer effect of its latex has been only been studied on a limited basis on several cell lines, such prostate cancer, breast cancer, and leukemia. In this study, we investigated the anti-cancer activity of the latex of Ficus carica L.and its underlying mechanism in FaDu human hypopharynx squamous carcinoma cells. (See Ed. note above) We confirmed through SDS-PAGE analysis and gelatinolytic activity analysis that the latex of Ficus carica contains cysteine protease ficin. Our data showed that the latex inhibited cell growth in a dose-dependent manner. In addition, the latex treatment markedly induced apoptosis in FaDu cells as determined by FACS analysis, elevated expression level of cleaved caspase-9, -3 and PARP (poly (ADP-ribose) polymerase), and. increased the expression of Bax (pro-apoptotic factor) while decreasing the expression of Bcl-2 (anti-apoptotic factor). Taken together, these results suggested that latex containing the ficin inhibited cell growth and induced apoptosis by caspase and the Bcl-2 family signaling pathway in FaDu human hypopharynx squamous carcinoma cells. These findings point to the potential of latex of Ficus carica to provide a novel chemotherapeutic drug due to its growth inhibition effects and induction of apoptosis in human oral cancer cells.

A Study on the Three-Dimensional Stability Analysis of the Slope (사면의 3차원 안정해석에 관한 연구)

  • Kim, Yeong-Su;Baek, Yeong-Sik;Seo, In-Seok
    • Geotechnical Engineering
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    • v.7 no.4
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    • pp.89-98
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    • 1991
  • This paper presents the three-dimensional stability analysis of the homogeneous, isotropic soil Slopes. Rotational slides are assumed with a cylindroid central part terminated with log-spiral curved ends. The ratio of threeiimensional minimum factor of safety to two 4imensional case is examined and factor of safety changes are showed for the ratio of cylinder length to slope height. On touch babes the following conclusions may be made 1. Factors of safety computed for 3-D geometry differ considerablely from ordir,arty 2-D factor of. safety. Sinoe Fn 1 Fa2 exceeds unity, threeiimensional effects tend to increase the factor of safety. 2. A,B LIU increase, the value of Fb3/ Fs2 decreases. 3. The ratio of Fr/Fs2 appears to be very sensitive to c and values.

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A Study on Selecting Green Indexes of a Seaport

  • Pak, Ji-Yeong;Yeo, Gi-Tae;Coo, Byung-Mo
    • Journal of Navigation and Port Research
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    • v.33 no.9
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    • pp.653-657
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    • 2009
  • The aim of this study draws out the Green Index of a Seaport (GIS) that is comprehensive and coordinated approach to diminish the negative impacts of port operations using a Factor Analysis (FA) which can evaluate the level of cleanness of seaport. For this purpose, the questionnaires were sent to the experts and port stake holders, and received 75 out of 100. In this survey, Cronbach's alpha has the numerical value 0.76. Thus it means that this survey has internal consistency reliability. Overall, 15 components were selected from the literature review and five factors were extracted by factor analysis.

Role of Forensic Accounting to Strengthen Corporate Governance : An Empirical Study

  • Bhasin, Madan Lal
    • The Journal of Economics, Marketing and Management
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    • v.5 no.1
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    • pp.1-20
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    • 2017
  • An increasing number of researchers are finding that 'poor' CG is a leading factor in dismal performance, manipulated financial reports, and unhappy stakeholders. Undoubtedly, qualified, trained and mature Chartered Forensic Accountants (CFA's) can prove to be a valuable asset to the corporate sector, and gradually help to improve their CG system. The fundamental objective of this study is to find out "how can we integrate the expertise of the FA to improve the overall CG scenario prevalent in India?" This is a preliminary investigation of the necessary skills, educational and training requirements for CFA's to improve CG system. During 2011-12, a questionnaire-based survey was conducted in the NCR of India using a sample size of 120 practicing chartered accountants, accounting academics, and potential users of FA services. Results indicate that potential practitioners, academics and users agree that "critical thinking, written & oral communication, legal knowledge, auditing skills, deductive analysis, investigative flexibility, analytical proficiency and unstructured problem-solving are the most important skills required for the CFAs." Moreover, we found that all of the skills investigated in this study are 'potentially' important for the CFAs, which the educators at the Universities should use as an overall guide while designing their FA curriculum."