Diagnose network failures via data-plane analysis

Diagnosing problems in networks is a time-consuming and error-prone process. Previous tools to assist operators primarily focus on analyzing control plane configuration. Configuration analysis is limited in that it cannot find bugs in router software, and is harder to generalize across protocols since it must model complex configuration languages and dynamic protocol behavior. This paper studies an alternate approach: diagnosing problems through static analysis of the data plane. This approach can catch bugs that are invisible at the level of configuration files, and simplifies unified analysis of a network across many protocols and implementations. We present Anteater, a tool for checking invariants in the data plane. Anteater translates high-level network invariants into boolean satisfiability problems, checks them against network state using a SAT solver, and reports counterexamples if violations have been found. Applied to a large campus network, Anteater revealed 23 bugs, including forwarding loops and stale ACL rules, with only five false positives. Nine of these faults are being fixed by campus network operators

Scene classification using spatial pyramid matching and hierarchical Dirichlet processes

The goal of scene classification is to automatically assign a scene image to a semantic category (i.e. building or river ) based on analyzing the visual contents of this image. This is a challenging problem due to the scene images\u27 variability, ambiguity, and a wide range of illumination or scale conditions that may apply. On the contrary, it is a fundamental problem in computer vision and can be used to guide other processes such as image browsing, contentbased image retrieval and object recognition by providing contextual information. This thesis implemented two scene classification systems: one is based on Spatial Pyramid Matching (SPM) and the other one is applying Hierarchical Dirichlet Processes (HDP). Both approaches are based on the most popular bag-of-words representation, which is a histogram of quantized visual features. SPM represents an image as a spatial pyramid which is produced by computing histograms of local features for multiple levels with different resolutions. Spatial Pyramid Matching is then used to estimate the overall perceptual similarity between images which can be used as a support vector machine (SVM) kernel. In the second approach, HDP is used to model the bag-of-words representations of images; each image is described as a mixture of latent themes and each theme is described as a mixture of words. The number of themes is automatically inferred from data. The themes are shared by images not only inside one scene category but also across all categories. Both systems are tested on three popular datasets from the field and their performances are compared. In addition, the two approaches are combined, resulting in performance improvement over either separate system

A parameterised model for link prediction using node centrality and similarity measure based on graph embedding

Link prediction is a key aspect of graph machine learning, with applications as diverse as disease prediction, social network recommendations, and drug discovery. It involves predicting new links that may form between network nodes. Despite the clear importance of link prediction, existing models have significant shortcomings. Graph Convolutional Networks, for instance, have been proven to be highly efficient for link prediction on a variety of datasets. However, they encounter severe limitations when applied to short-path networks and ego networks, resulting in poor performance. This presents a critical problem space that this work aims to address. In this paper, we present the Node Centrality and Similarity Based Parameterised Model (NCSM), a novel method for link prediction tasks. NCSM uniquely integrates node centrality and similarity measures as edge features in a customised Graph Neural Network (GNN) layer, effectively leveraging the topological information of large networks. This model represents the first parameterised GNN-based link prediction model that considers topological information. The proposed model was evaluated on five benchmark graph datasets, each comprising thousands of nodes and edges. Experimental results highlight NCSM's superiority over existing state-of-the-art models like Graph Convolutional Networks and Variational Graph Autoencoder, as it outperforms them across various metrics and datasets. This exceptional performance can be attributed to NCSM's innovative integration of node centrality, similarity measures, and its efficient use of topological information

Optimal subsampling algorithm for the marginal model with large longitudinal data

Big data is ubiquitous in practices, and it has also led to heavy computation burden. To reduce the calculation cost and ensure the effectiveness of parameter estimators, an optimal subset sampling method is proposed to estimate the parameters in marginal models with massive longitudinal data. The optimal subsampling probabilities are derived, and the corresponding asymptotic properties are established to ensure the consistency and asymptotic normality of the estimator. Extensive simulation studies are carried out to evaluate the performance of the proposed method for continuous, binary and count data and with four different working correlation matrices. A depression data is used to illustrate the proposed method

Supramolecular control over self-assembly and double thermoresponsive behavior of an amphiphilic block copolymer

A poly(ethylene glycol)-b-poly[N, N-dimethylacrylamide-ran-2-acrylamidoethyl nonanoate] (PEG-b-P(DMA-AAEN)) block copolymer has been demonstrated to show double thermoresponsive behavior in aqueous solution in the presence of hydroxypropylated cyclodextrin (HPCD). The polymer itself is insoluble in water due to the presence of hydrophobic alkyl chain, however, with the presence of HPCD, fully dissolution of the polymer could be obtained indicating the formation of host-guest interaction between HPCD and the alkyl chain. The clear solution of HPCD/polymer complex showing a first thermoresponsiveness during heating and led to the formation of small micelles stabilized by PEG chains and DMA segments. Upon further heating of the aqueous solution, the small micelles aggregated and formed multimicellar aggregates. The reported double thermoresponsive behavior may provide a new strategy of designing smart polymeric systems, which can find broad applications in the fabrication of smart materials

Progress and Review of the Research on School Physical Education Management in China

Reviewing and summarizing the research of school physical education management can promote school physical education work. The purpose of this study was twofold: (1) sorting out the achievements and shortcomings of the current research of school physical education management, and (2) putting forward prospects for the future research of school physical education management. In this review study, we followed three steps. We used the following keywords: “school physical education management”, OR “physical education management” for the literature search via the libraries resources of a large university in Shanghai, China. A total of 396 relevant articles were retrieved and then saved to a data processing computer. Then we collated and classified all the articles and then analyzed the management mode, management system and management method at the macro level, as well as the management of physical education teaching in schools, the management of physical education teachers, and the management of field equipment at the micro level. (1) Achievements: The research in the field of school physical education management gradually realized that it was difficult to adapt the experiential management to the new requirements of school physical education development, and began to explore management concept renewal. The research on the management model of school sports began to draw lessons from the management of school sports in developed countries and put forward innovative new models. The research on the management system of school physical education puts forward the existing problems and inadequacies based on the current management system. (2) Shortcomings: the research field of school physical education management is relatively narrow, and the research on primary and secondary education themes is scarce; Lack of empirical research; The current situation of management and countermeasures were mainly studied using questionnaire survey, and some studies ignored the basic knowledge of sports management in countermeasures analysis. Future research should take into account era background and the perspective of teaching integration; specifically, to strengthen the empirical research on the management of school physical education, broaden the school sports management research field of vision, the sports management expertise and school sports management research depth fusion, make school sports research has a broader coverage, deeper theoretical depth

Research Progress and Future Prospect of Dance Movement Therapy in China Based on a Citespace Visual Analysis

The purpose of this study was to (1) explore the research progress of dance movement therapy in China and (2) reveal future development trend of dance movement therapy. With the methods of literature review, logical induction and scientific knowledge mapping, the research results of dance movement therapy in China were analyzed visually. The co-occurrence chart of key words and timeline analysis chart of key words of dance movement therapy in China were created based on the data. The co-occurrence chart of key words showed that the research hotspots centered on dance therapy , psychotherapy , Parkinson\u27s disease , autism , special children , teenagers , college students and college students . The subjects of dance therapy were mainly special children, teenagers and college students. The diseases of dance therapy focused on Parkinson\u27s disease , schizophrenia , autism , social anxiety . Timeline analysis chart of key words showed that research subjects experienced trended from psychotherapy , autism to Parkinson\u27s disease and dance decompression . The patients in the study expanded from college students and autistic children to teenagers and college students . The auxiliary elements of dance therapy experienced the expansion from dance to music and art . On the basis of summarizing the experience gained from clinical practice, we should further clarify the operational definition and effect evaluation of dance therapy, and establish a complete and systematic dance analysis system. We should explore how to combine drug therapy with dance therapy, and study the best proportion of the two in the treatment. Under the background of the combination of medicine and sports, we should think about how to promote dance therapy, integrate dance therapy into disease prevention and treatment, and accelerate the advancement of the dance therapy industry

Analysis and Prospect of Research Progress of Health Education Curriculum in China

The purpose of this study was twofold: 1) review research results of health education in China and help readers gain a better understanding of the current profiles of research in health education curriculum and 2) provide a theoretical basis for future research in health education curriculum. Using key words such as health education curriculum on Chinese National Knowledge Infrastructure (CNKI), we searched and finally obtained 7287 articles. By using the visual analysis function of CNKI, we also analyzed the overall trend of research in Health Education Curriculum. Review of the articles found that the overall trend of research in health education curriculum in China has been growing since 1987, and has been growing at a steady rate since 2000. At present, the health education curriculum in China mainly consists of two forms: One is as part of physical education and health curriculum. The content generally focus on health knowledge, health habits, health concepts, and sports injury management and prevention in sports; The other form is a separate health education course. Its content generally includes mental health and health habits etc. At present, implementation of health education curriculum in China is mainly influenced by course time, teachers\u27 ability and evaluation mechanism. In the current research field of health education curriculum evaluation, there are more studies related to mental health curriculum evaluation, and the research in this area is mostly based on the construction of evaluation models, and more mature research results have been formed. However, the research on the evaluation of health education curriculum in physical education and health curriculum is relatively weak. Based on the progress of current research, future studies in health education curriculum should be carried out in the following aspects: 1) curriculum content: focusing on epidemic prevention and control theory and practice; 2) curriculum implementation: development of physical education teachers\u27 health knowledge literacy; and 3) curriculum evaluation: participation of multiple subjects

ENERGY YIELD CALCULATIONS FOR SILICON-BASED TANDEM SOLAR CELLS

Ph.DDOCTOR OF PHILOSOPH