Incremental algorithms for multilinear principal component analysis of tensor objects

In recent years, massive data sets are generated in many areas of science and business, and are gathered by using advanced data acquisition techniques. New approaches are therefore required to facilitate effective data management and data analysis in this big data era, especially to analyze multidimensional data for real-time applications. This thesis aims at developing generic and effective algorithms for compressing and recovering online multidimensional data, and applying such algorithms in image processing and other related areas. Since multidimensional data are usually represented by tensors, this research uses multilinear algebra as the mathematical foundation to facilitate development. After reviewing the techniques of singular value decomposition (SVD), principal component analysis (PCA) and tensor decomposition, this thesis deduces an effective multilinear principal component analysis (MPCA) method to process such data by seeking optimal orthogonal basis functions that map the original tensor space to a tensor subspace with minimal reconstruction error. Two real examples, 3D data compression for positron emission tomography (PET) and offline fabric defect detection, are used to illustrate the tensor decomposition method and the deduced MPCA method, respectively. Based on the deduced MPCA method, this research develops an incremental MPCA (IMPCA) algorithm which targets at compressing and recovering online tensor objects. To reduce computational complexity of the IMPCA algorithm, this research investigates the low-rank updates of singular values in the matrix and tensor domains, which leads to the development of a sequential low-rank update scheme similar to the sequential Karhunen-Loeve algorithm (SKL) for incremental matrix singular value decomposition, a sequential low-rank update scheme for incremental tensor decomposition, and a quick subspace tracking (QST) algorithm to further enhance the low-rank updates of singular values if the matrix is positive-symmetric definite. Although QST is slightly inferior to the SKL algorithm in terms of accuracy in estimating eigenvector and eigenvalue, the algorithm has lower computational complexity. Two fast incremental MPCA (IMPCA) algorithms are then developed by incorporating the SKL algorithm and the QST algorithm separately into the IMPCA algorithm. Results obtained from applying the developed IMPCA algorithms to detect anomalies from online multidimensional data in a number of numerical experiments, and to track and reconstruct the global surface temperature anomalies over the past several decades clearly confirm the excellent performance of the algorithms. This research also applies the developed IMPCA algorithms to solve an online fabric defect inspection problem. Unlike existing pixel-wise detection schemes, the developed algorithms employ a scanning window to extract tensor objects from fabric images, and to detect the occurrence of anomalies. The proposed method is unsupervised because no pre-training is needed. Two image processing techniques, selective local Gabor binary patterns (SLGBP) and multi-channel feature combination, are developed to accomplish the feature extraction of textile patterns and represent the features as tensor objects. Results of experiments conducted by using a real textile dataset confirm that the developed algorithms are comparable to existing supervised methods in terms of accuracy and computational complexity. A cost-effective parallel implementation scheme is developed to solve the problem in real-time.published_or_final_versionIndustrial and Manufacturing Systems EngineeringDoctoralDoctor of Philosoph

Relationship between Rural Industry Revitalization and Land Resource Utilization and Its Practice in Ganning Town, Wanzhou District of Chongqing

[Objectives] To explore the relationship between rural industry revitalization and land resource utilization. [Methods] Starting from the connotation of rural industry revitalization and land resource utilization, this study explores the relationship between rural industry revitalization and land resource utilization, Taking Ganning Town with typical mountain industry as the research area, this paper analyzed the relationship between rural industry revitalization and land resource utilization through a combination of field research and literature analysis, found out the existing problems and came up with pertinent recommendations. [Results] (i) Rural industry revitalization is both mutually reinforcing and mutually restrictive. (ii) In this study, the land use types of Ganning Town were divided into nine categories, including farmland, garden land, forest land and grassland, and their industrial functions and development models were identified, and the corresponding framework of land resource utilization and rural industry revitalization in Ganning Town was constructed. (iii) In view of the problems existing in Ganning Town, this paper proposed to change the ideological concept and enhance understanding, improve the utilization rate of idle land and promote rural industry revitalization, and accelerate land consolidation and restoration, and promote sustainable development. [Conclusions] It is necessary to correctly understand the two-way role and dynamic change relationship between rural industry revitalization and land resource utilization, solve the problem from the perspective of development, adopt development strategies according to local conditions, and take the road of sustainable development

Relationship between Rural Industry Revitalization and Land Resource Utilization and Its Practice in Ganning Town, Wanzhou District of Chongqing

[Objectives] To explore the relationship between rural industry revitalization and land resource utilization. [Methods] Starting from the connotation of rural industry revitalization and land resource utilization, this study explores the relationship between rural industry revitalization and land resource utilization, Taking Ganning Town with typical mountain industry as the research area, this paper analyzed the relationship between rural industry revitalization and land resource utilization through a combination of field research and literature analysis, found out the existing problems and came up with pertinent recommendations. [Results] (i) Rural industry revitalization is both mutually reinforcing and mutually restrictive. (ii) In this study, the land use types of Ganning Town were divided into nine categories, including farmland, garden land, forest land and grassland, and their industrial functions and development models were identified, and the corresponding framework of land resource utilization and rural industry revitalization in Ganning Town was constructed. (iii) In view of the problems existing in Ganning Town, this paper proposed to change the ideological concept and enhance understanding, improve the utilization rate of idle land and promote rural industry revitalization, and accelerate land consolidation and restoration, and promote sustainable development. [Conclusions] It is necessary to correctly understand the two-way role and dynamic change relationship between rural industry revitalization and land resource utilization, solve the problem from the perspective of development, adopt development strategies according to local conditions, and take the road of sustainable development

Ultrastructure characteristics and quality changes of low-moisture Chilgoza pine nut (Pinus gerardiana) during the near-freezing-temperature storage

The effects of thermal treatment on the ultrastructure and quality of Chilgoza pine nuts stored at near-freezing temperature were investigated. The moisture content of pine nuts was adjusted to 13.3%, compared to the initial 17.3% moisture content. Thermal treatment improved the storage stability. The hydrolysis of lipids was delayed in low-moisture pine nuts, resulting in a significant inhibition of free fatty acid accumulation in pine nuts. Low-moisture pine nuts also showed lower peroxide and thiobarbituric acid (TBA)​ values compared with the control. Ultrastructure characterization revealed that thermal treatment maintained the cell integrity, deferred the degradation of the plasmalemma and protected the internal lipid droplet. Thermal treatment better retained the antioxidant components, including total phenolics and vitamin E, and reduced the activities of lipase and lipoxygenase in pine nuts. These results indicated that thermal treatment could retard the senescence and deterioration of quality in pine nuts stored at a near-freezing temperature.Se investigaron los efectos del tratamiento térmico en la ultrastructura y la calidad del piñón de pino Chilgoza almacenado a una temperatura cercana a congelación. El contenido de humedad de los piñones de este pino fue de 13,3%, en comparación con el contenido de humedad inicial de 17,3%. El tratamiento térmico mejoró la estabilidad de almacenamiento. La hidrólisis de los lípidos se retardó en los piñones de pino de baja humedad, resultando en una inhibición significativa de la acumulación de ácidos grasos libres en los piñones. Los piñones de pino de baja humedad también mostraron unos índices bajos de peróxido y TBA en comparación con la muestra control. La caracterización de la ultrastructura reveló que el tratamiento térmico mantuvo la integridad de las células, atrasó la degradación de la plasmalema y protegió la gota lipídica interna. El tratamiento térmico retuvo de forma más favorable los componentes antioxidantes, como el total fenólico y la vitamina E, además redujo la actividad de la lipasa y la lipoxigenasa en los piñones. Estos resultados indicaron que el tratamiento térmico podría retardar la senescencia y la deterioración de la calidad de los piñones almacenados a una temperatura cercana a la congelación