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Determination of the principal factors of river water quality through cluster analysis method and its

Liang GUO, Ying ZHAO, Peng WANG

《环境科学与工程前沿（英文）》 2012年第6卷第2期页码 238-245 doi: 10.1007/s11783-011-0382-7

摘要： In this paper, an artificial neural network model was built to predict the Chemical Oxygen Demand (COD ) measured by permanganate index in Songhua River. To enhance the prediction accuracy, principal factors were determined through the analysis of the weight relation between influencing factors and forecasting object using cluster analysis method, which optimized the topological structure of the prediction model input items of the artificial neural network. It was shown that application of the principal factors in water quality prediction model can improve its forecasting skill significantly through the comparison between results of prediction by artificial neural network and the measurements of the COD . This methodology is also applicable to various water quality prediction targets of other water bodies and it is valuable for theoretical study and practical application.

关键词： water quality forecast principal factor cluster analysis method artificial neural network

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Shaking-moment balancing of mechanisms with principal vectors and momentum

V. van der WIJK

《机械工程前沿（英文）》 2013年第8卷第1期页码 10-16 doi: 10.1007/s11465-013-0359-2

摘要：

The design of shaking-moment-balanced linkages still is challenging. Considering moment balance in the very beginning of the design process of mechanisms is important for finding applicable solutions. For this purpose, the method of principal vectors is investigated, showing a compact notation of the angular momentum with respect to the center of mass. The moment balance conditions are derived for three elements in series from which balance solutions are synthesized and illustrated. From the application for moment balancing of a 4R four-bar linkage it is shown that the moment balancing of closed kinematic chains remains challenging.

关键词： shaking-moment balancing principal vector linkage angular momentum

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Non-negativematrix factorization based unmixing for principal component transformed hyperspectral data

Xiu-rui GENG,Lu-yan JI,Kang SUN

《信息与电子工程前沿（英文）》 2016年第17卷第5期页码 403-412 doi: 10.1631/FITEE.1600028

摘要： Non-negative matrix factorization (NMF) has been widely used in mixture analysis for hyperspectral remote sensing. When used for spectral unmixing analysis, however, it has two main shortcomings: (1) since the dimensionality of hyperspectral data is usually very large, NMF tends to suffer from large computational complexity for the popular multiplicative iteration rule; (2) NMF is sensitive to noise (outliers), and thus the corrupted data will make the results of NMF meaningless. Although principal component analysis (PCA) can be used to mitigate these two problems, the transformed data will contain negative numbers, hindering the direct use of the multiplicative iteration rule of NMF. In this paper, we analyze the impact of PCA on NMF, and find that multiplicative NMF can also be applicable to data after principal component transformation. Based on this conclusion, we present a method to perform NMF in the principal component space, named ‘principal component NMF’ (PCNMF). Experimental results show that PCNMF is both accurate and time-saving.

关键词： Non-negative matrix factorization (NMF) Principal component analysis (PCA) Endmember Hyperspectral

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optimization of cutting parameters in high-speed milling based on grey relational analysis coupled with principal

Tao FU, Jibin ZHAO, Weijun LIU

《机械工程前沿（英文）》 2012年第7卷第4期页码 445-452 doi: 10.1007/s11465-012-0338-z

摘要：

This paper investigates optimization problem of the cutting parameters in high-speed milling on NAK80 mold steel. An experiment based on the technology of Taguchi is performed. The objective is to establish a correlation among spindle speed, feed per tooth and depth of cut to the three directions of cutting force in the milling process. In this study, the optimum cutting parameters are obtained by the grey relational analysis. Moreover, the principal component analysis is applied to evaluate the weights so that their relative significance can be described properly and objectively. The results of experiments show that grey relational analysis coupled with principal component analysis can effectively acquire the optimal combination of cutting parameters and the proposed approach can be a useful tool to reduce the cutting force.

关键词： high-speed milling grey relational analysis principal component analysis parameters optimization

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工程监理委托代理关系中激励约束与参与约束的研究

秦旋

《中国工程科学》 2007年第9卷第4期页码 45-49

摘要：

基于委托－代理理论对工程监理委托－代理关系中的激励约束与参与约束进行若干拓展研究，与参与约束（IR）相比，激励相容约束（IC）更为重要，一个机制不满足激励约束，那将是一个无效机制。业主想要提高工程监理制度的运作效率，就必须通过相应的激励措施诱使工程师努力工作，使“道德风险”得以抑制，为我国工程监理制度的健康发展提供了有益的启示。

关键词：工程监理业主工程师委托代理激励相容约束参与约束

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一种基于主成分分析的企业并购目标遴选综合评价模型探讨

罗一新

《中国工程科学》 2009年第11卷第11期页码 92-96

摘要：

在广泛调查研究的基础上，提出了并购目标企业的遴选综合评价指标体系，利用主成分法建立了综合评价模型，并结合实际案例进行了分析，结果证明了评价指标体系和遴选评价模型的可行性，并通过建模计算，对多个并购目标进行排序，为我国正处发展期的企业并购活动提供了一种可行的、便于辅助买方企业决策的并购目标遴选综合评价方法。

关键词：主成分分析企业并购目标遴选评价指标体系评价模型

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弧齿锥齿轮主曲率计算的幺正活动标架法

王裕清,梁剑

《中国工程科学》 2001年第3卷第12期页码 68-70

摘要：

曲面上点的主曲率计算是确定轮齿啮合压痕平面投影形状的关键。文章摈弃通常运用啮合原理和坐标变换计算的思路，从曲面本身的性质出发，把幺正活动标架和外微分引入主曲率计算，得到简明、有效的主曲率计算的新算法，并结合压痕公式给出了一个应用实例。该算法可以推广到任意曲面的主曲率计算。

关键词：弧齿锥齿轮主曲率幺正活动标架

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AED-Net——异常事件检测网络 Article

王田, 苗子琛, 陈禹昕, 周毅, 单光存, Hichem Snoussi

《工程（英文）》 2019年第5卷第5期页码 930-939 doi: 10.1016/j.eng.2019.02.008

摘要：

长期以来，在拥挤场景中检测异常事件都是一项具有挑战性的任务。为解决这一问题，本文提出了一种名叫异常事件检测网络（AED-Net）的自监督框架，它由主成分分析网络（PCANet）和核主成分分析（kPCA）组成。该框架以不同场景的监控视频序列为原始数据，通过训练PCANet以提取人群情况的高级语义。kPCA可作为一种单类分类器，被用于识别场景中的异常事件。与目前流行的一些深度学习方法相比，该框架完全是自监督的，因为它只使用正常情况下的视频序列。通过对明尼苏达大学公共监测人类活动数据集（UMN数据集）和加州大学圣地亚哥分校监测异常数据集（UCSD数据集）进行全局和局部异常事件进行检测发现，与其他最先进的方法相比，该方法具有更好的等误差率（EER）和曲线下面积（AUC）。此外，通过增加局部响应归一化（LRN）层，我们对原有的AED-Net进行了改进。结果表明，该改进版在提高框架的泛化能力方面表现出更好的性能。

关键词：异常事件检测异常事件检测网络主成分分析网络核主成分分析

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Role of the forkhead transcription factor FOXO-FOXM1 axis in cancer and drug resistance

null

《医学前沿（英文）》 2012年第6卷第4期页码 376-380 doi: 10.1007/s11684-012-0228-0

摘要：

The forkhead transcription factors FOXO and FOXM1 have pivotal roles in tumorigenesis and in mediating chemotherapy sensitivity and resistance. Recent research shows that the forkhead transcription factor FOXM1 is a direct transcriptional target repressed by the forkhead protein FOXO3a, a vital downstream effector of the PI3K-AKT-FOXO signaling pathway. Intriguingly, FOXM1 and FOXO3a also compete for binding to the same gene targets, which have a role in chemotherapeutic drug action and sensitivity. An understanding of the role and regulation of the FOXO-FOXM1 axis will impact directly on our knowledge of chemotherapeutic drug action and resistance in patients, and provide new insights into the design of novel therapeutic strategy and reliable biomarkers for prediction of drug sensitivity.

关键词： FOXO3a FOXM1 transcription factor cancer drug resistance tumorigenesis

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基于主成分综合模型的矿区农田重金属污染评价

王从陆,吴超,段瑜

《中国工程科学》 2008年第10卷第7期页码 180-183

摘要：

文章尝试利用变量聚类分析方法对矿区附近农田土壤重金属污染的主要污染物进行辨识，并采用综合主成分分析法对矿区附近农田土壤重金属污染情况进行评价和分级。分析结果表明：利用变量聚类分析法可以有效地辨识矿区附近农田土壤重金属污染中的主要成分；运用综合主成分分析法，确定样本的综合主成分，并对其排序和聚类，可以有效揭示矿区附近农田土壤重金属污染物的数据结构、相互关系和不同样品点的污染程度。采用主成分分析方法对矿区附近农田土壤重金属污染情况的评价结果，反映了矿区主要重金属污染物的影响，同时又定量化了土壤复合重金属污染研究。辨识和评价结果可为矿区附近农田土壤重金属污染治理对策的提出和重点治理区域的确定提供参考和指导。

关键词：主成分综合模型矿区农田土壤重金属污染评价

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LSSVM-based approach for refining soil failure criteria and calculating safety factor of slopes

Shiguo XIAO; Shaohong LI

《结构与土木工程前沿（英文）》 2022年第16卷第7期页码 871-881 doi: 10.1007/s11709-022-0863-8

摘要： The failure criteria of practical soil mass are very complex, and have significant influence on the safety factor of slope stability. The Coulomb strength criterion and the power-law failure criterion are classically simplified. Each one has limited applicability owing to the noticeable difference between calculated predictions and actual results in some cases. In the work reported here, an analysis method based on the least square support vector machine (LSSVM), a machine learning model, is purposefully provided to establish a complex nonlinear failure criterion via iteration computation based on strength test data of the soil, which is of more extensive applicability to many problems of slope stability. In particular, three evaluation indexes including coefficient of determination, mean absolute percentage error, and mean square error indicate that fitting precision of the machine learning-based failure criterion is better than those of the linear Coulomb criterion and nonlinear power-law criterion. Based on the proposed LSSVM approach to determine the failure criterion, the limit equilibrium method can be used to calculate the safety factor of three-dimensional slope stability. Analysis of results of the safety factor of two three-dimensional homogeneous slopes shows that the maximum relative errors between the proposed approach and the linear failure criterion-based method and the power-law failure criterion-based method are about 12% and 7%, respectively.

关键词： slope stability safety factor failure criterion least square support vector machine

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lncR-GAS5 upregulates the splicing factor to impair endothelial autophagy, leading to atherogenesis

《医学前沿（英文）》 2023年第17卷第2期页码 317-329 doi: 10.1007/s11684-022-0931-4

摘要： Long noncoding RNAs (lncRNAs) play a critical role in the regulation of atherosclerosis. Here, we investigated the role of the lncRNA growth arrest-specific 5 (lncR-GAS5) in atherogenesis. We found that the enforced expression of lncR-GAS5 contributed to the development of atherosclerosis, which presented as increased plaque size and reduced collagen content. Moreover, impaired autophagy was observed, as shown by a decreased LC3II/LC3I protein ratio and an elevated P62 level in lncR-GAS5-overexpressing human aortic endothelial cells. By contrast, lncR-GAS5 knockdown promoted autophagy. Moreover, serine/arginine-rich splicing factor 10 (SRSF10) knockdown increased the LC3II/LC3I ratio and decreased the P62 level, thus enhancing the formation of autophagic vacuoles, autolysosomes, and autophagosomes. Mechanistically, lncR-GAS5 regulated the downstream splicing factor SRSF10 to impair autophagy in the endothelium, which was reversed by the knockdown of SRSF10. Further results revealed that overexpression of the lncR-GAS5-targeted gene miR-193-5p promoted autophagy and autophagic vacuole accumulation by repressing its direct target gene, SRSF10. Notably, miR-193-5p overexpression decreased plaque size and increased collagen content. Altogether, these findings demonstrate that lncR-GAS5 partially contributes to atherogenesis and plaque instability by impairing endothelial autophagy. In conclusion, lncR-GAS5 overexpression arrested endothelial autophagy through the miR-193-5p/SRSF10 signaling pathway. Thus, miR-193-5p/SRSF10 may serve as a novel treatment target for atherosclerosis.

关键词： lncR-GAS5 miR-193-5p splicing factor SRSF10 autophagy atherogenesis

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基于主成分分析法的秦巴山脉区域林业产业发展研究

郑东晖,后华,翟明普,渠美

《中国工程科学》 2020年第22卷第1期页码 120-126 doi: 10.15302/J-SSCAE-2020.01.013

摘要：

林业产业作为国民经济的重要基础性产业，在生态建设中的地位日益突出。本文系统梳理了秦巴山脉区域的林业产业发展现状，详细开展了区域林业产业的优势、劣势、机遇和威胁（SWOT）分析，以专家问卷调查作为数据来源，运用主成分分析方法，以统计分析的方式寻找出对秦巴山脉林业产业发展有较大影响的要素，以之作为区域林业产业发展战略制定的科学依据。研究表明，生态环境问题、集约化程度低、森林旅游业发展机遇、区位优势、资源优势等方面是秦巴山脉区域林业产业发展的主要影响因素；区域林业产业发展重在于生态建设，应利用区位和资源优势，做大做强特色产业，优化产业结构；同时大力发展以森林旅游为主的第三产业，保障区域林业产业的高质量发展。

关键词：秦巴山脉区域林业产业 SWOT分析主成分分析法生态环境

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The calculation of equivalence factor for ecological footprints in China: a methodological note

Moucheng LIU,Wenhua LI,Dan ZAHNG,Ning SU

《环境科学与工程前沿（英文）》 2015年第9卷第6期页码 1015-1024 doi: 10.1007/s11783-014-0670-0

摘要： The Ecological Footprint (EF), a physical indicator to measure the extent of humanity’s use of natural resources, has gained much attention since it was first used by Wackernagel and Rees in 1996. In order to appraise land area types with different levels of productivity, they introduced the concept of an equivalence factor. This relates to the average primary biomass productivities of different types of land (i.e. arable land, pasture, forest, water/fishery, built-up land and fossil energy land) to the regional average primary biomass productivity of all land types in a given year. Hence, the equivalence factor is an important parameter in the EF model and it directly affects the reliability of all results. Thus, this article calculates equivalence factors on the national and provincial levels in China based on Net Primary Production (NPP) from MODIS 1 km data in 2008. Firstly, based on the Light Utility Efficiency and CASA model, the NPP of different biologically productive lands of China and of different provinces was calculated. Secondly, China’s equivalence factor for 6 land area types was calculated based on NPP: arable land and built-up land has an equivalence factor of 1.71, forest and fossil energy land has a factor of 1.41, pasture has a factor of 0.44 and water/fishery 0.35; Finally, the equivalence factor of 6 land area types in different provinces was also calculated. The NPP of each ecosystem type varies along with the equivalence factor in different provinces. However, the ranking of the equivalence factors in different provinces remain the same, with that of arable land being the largest, and the water/fishery being the smallest.

关键词： ecological footprint equivalence factor net primary production biological capacity land types

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A practical multi-lane factor model of bridges based on multi-truck presence considering lane load disparities

《结构与土木工程前沿（英文）》 2021年第15卷第4期页码 877-894 doi: 10.1007/s11709-021-0756-2

摘要： Many bridge design specifications consider multi-lane factors (MLFs) a critical component of the traffic load model. Measured multi-lane traffic data generally exhibit significant lane disparities in traffic loads over multiple lanes. However, these disparities are not considered in current specifications. To address this drawback, a multi-coefficient MLF model was developed based on an improved probabilistic statistical approach that considers the presence of multiple trucks. The proposed MLF model and approach were calibrated and demonstrated through an example site. The model sensitivity analysis demonstrated the significant influence of lane disparity of truck traffic volume and truck weight distribution on the MLF. Using the proposed approach, the experimental site study yielded MLFs comparable with those directly calculated using traffic load effects. The exclusion of overloaded trucks caused the proposed approach, existing design specifications, and conventional approach of ignoring lane load disparity to generate comparable MLFs, while the MLFs based on the proposed approach were the most comprehensive. The inclusion of overloaded trucks caused the conventional approach and design specifications to overestimate the MLFs significantly. Finally, the benefits of the research results to bridge practitioners were discussed.

关键词： bridges multi-lane factor traffic load lane load disparity multi-truck presence weigh-in-motion data