Research on Parallel Topology Analysis Algorithm Based on Simulated Annealing

This paper delves into the critical issues of relay protection setting calculation in high-voltage power grids with large-scale integration of renewable energy sources, such as wind and solar power. By analyzing the topological structure of renewable energy systems, models of permanent magnet direct-drive wind turbines and photovoltaic power sources are established, with a particular focus on the short-circuit current characteristics of these renewable energy sources. Subsequently, a fault iterative method for short-circuit current calculation is proposed. This method effectively improves the accuracy of short-circuit current calculation by iteratively analyzing the fault region and considering the voltage-controlled current source characteristics of renewable energy sources. The paper also conducts in-depth research on various aspects of relay protection settings after the integration of renewable energy devices, including main transformer neutral grounding strategies, tie-line protection and reclosing principles, islanding prevention, and boundary backup protection management. By applying this method to a practical engineering case in G Province, China, the short-circuit current is calculated, and partial setting values are determined, demonstrating the ability of this method to enhance system safety and stability. This research provides valuable insights for operators of modern power systems.

This paper provides an overview of the threat of intense geomagnetic storms created by solar activity to high voltage power grids on the Earth. Given a description of the time and spatial variation of the geomagnetic field (past, present or future), it is possible to model the response of any specific high-voltage grid with a high level of accuracy. It is also clear from the available data that the higher the voltage of the AC power system, the more vulnerable that system is to a particular geomagnetic storm. Given the ability to model and with an understanding of transformer behavior, it is possible to design protection for high-voltage grids against this unique threat.

In recent years, with the deepening of smart grid construction, the data generated by power grid operation have increased rapidly, and the power grid big data environment has gradually formed. The power grid data management based on graph data has gained more and more attention, and its efficient storage and processing have become a research hotspot. In this paper, a subgraph partitioning algorithm for power grid graph data is developed. The power grid graph data are partitioned into multiple subgraphs, and then a parallel topology analysis algorithm for multiple subgraphs is proposed. Related experiments show that the parallel analysis scheme of power grid graph data is effective and meets the actual needs of power grid graph data.

In recent years, data center network is used for transmission, storage and processing of big data, which plays an important role for applications in cloud computing and CDN distribution. Network topology and routing algorithm are its core research content and key technical issues. The traditional network topology is difficult to guarantee the quality of service in scalability and fault tolerance. The server-centric data center network topology can ensure the scale of the data center network by recursively increasing the number of network nodes and links. relative to the Dcell, BCube, and BCCC typical network topology, PTNet network as a typical representative of a new type of the server-centric data center network topology, which has more advantages in scalability, fault tolerance and so on. Multicast and broadcast in data center network have more application scenarios and use value. For example, the video conference online, multimedia remote education and other development are inseparable from the application and promotion of network multicast and broadcast. So it is necessary to research the routing algorithms of multicast and broadcast in the network. Based on the deep research of PTNet network, this paper analyzes and researches the network topology, multicast and broadcast routing algorithm.

Large-scale power grid will inevitably become a new trend in the development of power systems, thus the power grid structure will become increasingly complex. The traditional topology analysis method can not meet the requirements of real-time. Therefore a parallel topology analysis preconditioning strategy based on community discovery algorithm was proposed. This strategy effectively utilized the maximum edge betweenness to achieve the topological division of the power grid, which laid the foundation for the parallel topology formation mechanism between the multiple regions of the power grid. On the basis of topological division, the regional grid can be parallel and asynchronous to form the topology, thus according to certain communication and coordination rules, the construction of the global power grid topology can be completed through the distributed computing, which can significantly improve the efficiency of topology analysis.

One of the steps of geometric modeling is to know the topology and/or the geometry of the objects considered. This paper presents different data structures and algorithms used in this study. We are particularly interested by algebraic structures, eg homotopy and homology groups, the Betti numbers, the Euler characteristic, or the Morse-Smale complex. We have to be able to compute these data structures, and for (homotopy and homology) groups, we also want to compute their generators. We are also interested in algorithms CIA and HIA presented in the thesis of Nicolas DELANOUE, which respectively compute the connected components and the homotopy type of a set defined by a CSG (constructive solid geometry) tree. We would like to generalize these algorithms to sets defined by projection.

The most common primary malignant bone sarcoma is Osteogenic sarcoma (OS) which has a bimodal age distribution. Unfortunately, the treatment of OS was less effective for elderly patients than for younger ones. The study aimed to explore a new microRNA (miRNA) which can bind to combining engineered exosomes for treatment of older OS patients. Based on GSE65071 and miRNet 2.0, two up-regulated miRNAs (miR-328, miR-107) and seven down-regulated miRNAs (miR-133b, miR-206, miR-1-3p, miR-133a, miR-449a, miR-181daysay, miR-134) were selected. Next, we used FunRich software to predict the up-stream transcription factors (TFs) of differentially expressed miRNAs (DE-miRNAs). By comparing target genes predicted from DE-miRNAs with differentially expressed genes, we identified 12 down-regulated and 310 up-regulated mRNAs. For KEGG analysis, the most enriched KEGG pathway was Cell cycle, Spliceosome, and Protein digestion and absorption. By using protein-protein interactions network, topological analysis algorithm and GEPIA database, miR-449a /CCNB1 axis was identified. Experiments in vitro were conducted to confirm the results too. MiRNA-449a is down-regulated in osteosarcoma and suppresses cell proliferation by targeting CCNB1. Our findings not only reveal a novel mechanism of miR-449a /CCNB1 in OS but also had laid the groundwork for further investigation and analysis in the field of exosome engineering.

In the related work of power grid safety, safety protection can be said to be a very basic work. Nowadays, with the continuous development of science and technology in China, a large-scale smart high-voltage power grid has been formed. In the actual operation of smart high-voltage power grid, if the safety automatic device owned by it has an accident, it is very easy to cause abnormal operation of the system, wrong operation and other situations, thus destroying the working performance of the power grid equipment. When there is a large current passing through the system in a short time, the relay protection device will be triggered, which will seriously affect the normal operation of the power grid.

Summary The Simulated Annealing (SA) algorithm has been widely used in geophysical data processing. However, the seri al SA algorithm is limited by low computing efficiency. In this paper, the annealing schedule has been improved in the SA algorithm, and a constrained inversion of magnetotelluric (MT) data using the parallel SA algorithm has been applied. The test of synthetic data shows that the improved Very Fast Simulated Annealing (VFSA) method is significantly better than the traditional method. Additionally, the computing efficiency has been improved using the parallel SA inversion algorithm. This method has also been applied in MT data processing for geothermal exploration and good geological results have been achieved.

Rayleigh wave inversion using heat-bath simulated annealing algorithm

Vector polygon overlay is a complex type of a geo-spatial analysis algorithm used in geographical information system, which requires increasingly higher computational efficiency given the rapid growth of spatial data sets. Parallel computing has provided an effective approach to improve the computational efficiency and expand the processing scales of polygon overlay algorithms. Polygon overlay analysis algorithms that are based on traditional vector polygon clipping algorithms will experience significant efficiency decreases when handling overlap among polygons that have quantities of vertices. The discretization processing method-based rasterization-based polygon clipping algorithm (RaPC) algorithm exhibits higher efficiency for addressing clipping issues among such polygons. In this paper, we designed and implemented two types of parallel polygon overlay analysis algorithms to determine the differences in efficiency between the RaPC algorithm and the Vatti algorithm under the open multi-processing and message passing interface parallel computing environments. The results show that parallel polygon overlay analysis methods based on the RaPC algorithm present advantages for processing overlap among large data sets. The parallel algorithm based on the Vatti algorithm presents higher efficiency when handling overlap among small spatial data sets. The discretization process between two overlapped geometries of the RaPC algorithm provided a potential approach to solve the polygon overlay problem using a fine-grained parallelization method.

In order to meet the requirement of time overhead of on-line setting and checking system of high voltage grid in coalmine, when the number of high voltage switches in high voltage grid of coalmine is more, it is necessary to solve the problem of reducing the time overhead of setting the relay protection of all high voltage switches in the whole mine high voltage power supply system. In order to improve the efficiency of setting calculation, this paper presents a parallel setting calculation method for high voltage power supply system in coalmine. According to the obtained topology analysis model, parallel setting calculation of all high-voltage switch branches of high-voltage power supply system in coalmine is realized based on the first-come first serve parallel scheduling strategy. The simulation results show that the proposed method can effectively reduce the time overhead and improve the computational efficiency.

Based on benchmarking various methods and analyzing multiple real scRNA-seq datasets, a computational platform/workflow and a set of tips for best practices are developed for analyzing causal interactions or relationships in single cells.

Customized network-oriented communication architectures have recently become a must to support high bandwidth SoCs. To this end, a corresponding communication design flow is necessary to support the design space exploration of complex SoCs with tight design constraints. In order to exploit the benefits introduced by the NoC approach for the on-chip communication, the paper presents a Pareto Simulated Annealing (PSA) approach for the customization of the network topology. The proposed PSA approach has been applied to STNoC, the Network on-Chip developed by STMicroelectronics. Starting from the ring topology, the proposed application-specific design flow tries to find a set of customized topologies (optimized in terms of performance and area/energy overhead) by adding custom links up to the spidergon topology.

Parallel analysis has received much support and attention as a criterion for using eigenvalues to determine the dimensionality of data. Parallel analysis compares sample eigenvalues to expected eigenvalues of a sample from a correlation matrix generated by independent normally distributed random variables. To make parallel analysis more accessible to researchers, several studies have proposed multiple regression equations for estimating the expected value of the eigenvalues of a sample correlation matrix assuming that the population correlation matrix is the identity matrix. A new regression equation to estimate the mean value of eigenvalues is presented in this article and a comparative study reveals favorable performance of this proposed equation to previously published regression equations. This proposed technique has the advantage that a table of coefficients, listing regression coefficients for each eigenvalue root, is not needed.