42 research outputs found
Concurrent High-performance Persistent Hash Table In Java
Current trading systems must handle both high volumes of trading and large amounts of trading data. One crucial module in high-performance trading is fast storage and retrieval of large volumes of data simultaneously accessed by multiple computer traders. To speed up access, a high-performance in-memory software-cache stores the dynamic working-set of trades during a trading day. To utilize memory effeciently, it is beneficial to provide a single shared cache for multiple trading applications. Much of the cache access is read-only, as information is gathered before a transaction to determine its value. Hence, extremely fast lookup is essential to support quick information gathering for assessment. This thesis presents a software-cache, called MapHash, that is a high-performance hash-table for use in Java
Towards practical use of Bloom Filter based IP lookup in operational network
International audienceBloom Filter is a widely used data structure in computer science. It enables memory efficient and fast set membership queries. Bloom filter-based solutions have been proposed in the past decade for lookup in forwarding tables of backbone routers [2]. However, the main shortcomings of using Bloom Filters for lookup lie in the absence of support for deletion operations that are needed to update the forwarding tables. Counting Bloom Filter supporting deletion has therefore to be used, increasing significantly the memory requirement. Moreover, Counting Bloom Filter suffers from both false positive and false negative. In this paper, we propose to solve the issue with deletion of Bloom Filters by using a Withdrawal To annOuncement (WTO) mapping that replaces withdrawal with announcements, transforming deletions into additions or record changes. Experimental evaluation show that the proposed techniques improve largely the performance of Bloom Filter used for forwarding lookup and open way for the use of Bloom Filters in real operational settings
GaitStrip: Gait Recognition via Effective Strip-based Feature Representations and Multi-Level Framework
Many gait recognition methods first partition the human gait into N-parts and
then combine them to establish part-based feature representations. Their gait
recognition performance is often affected by partitioning strategies, which are
empirically chosen in different datasets. However, we observe that strips as
the basic component of parts are agnostic against different partitioning
strategies. Motivated by this observation, we present a strip-based multi-level
gait recognition network, named GaitStrip, to extract comprehensive gait
information at different levels. To be specific, our high-level branch explores
the context of gait sequences and our low-level one focuses on detailed posture
changes. We introduce a novel StriP-Based feature extractor (SPB) to learn the
strip-based feature representations by directly taking each strip of the human
body as the basic unit. Moreover, we propose a novel multi-branch structure,
called Enhanced Convolution Module (ECM), to extract different representations
of gaits. ECM consists of the Spatial-Temporal feature extractor (ST), the
Frame-Level feature extractor (FL) and SPB, and has two obvious advantages:
First, each branch focuses on a specific representation, which can be used to
improve the robustness of the network. Specifically, ST aims to extract
spatial-temporal features of gait sequences, while FL is used to generate the
feature representation of each frame. Second, the parameters of the ECM can be
reduced in test by introducing a structural re-parameterization technique.
Extensive experimental results demonstrate that our GaitStrip achieves
state-of-the-art performance in both normal walking and complex conditions.Comment: Accepted to ACCV202
Deep Learning Reveals Key Immunosuppression Genes and Distinct Immunotypes in Periodontitis
Background: Periodontitis is a chronic immuno-inflammatory disease characterized
by inflammatory destruction of tooth-supporting tissues. Its pathogenesis involves a
dysregulated local host immune response that is ineffective in combating microbial
challenges. An integrated investigation of genes involved in mediating immune response
suppression in periodontitis, based on multiple studies, can reveal genes pivotal to
periodontitis pathogenesis. Here, we aimed to apply a deep learning (DL)-based
autoencoder (AE) for predicting immunosuppression genes involved in periodontitis by
integrating multiples omics datasets.
Methods: Two periodontitis-related GEO transcriptomic datasets (GSE16134 and
GSE10334) and immunosuppression genes identified from DisGeNET and HisgAtlas
were included. Immunosuppression genes related to periodontitis in GSE16134
were used as input to build an AE, to identify the top disease-representative
immunosuppression gene features. Using K-means clustering and ANOVA, immune
subtype labels were assigned to disease samples and a support vector machine
(SVM) classifier was constructed. This classifier was applied to a validation set
(Immunosuppression genes related to periodontitis in GSE10334) for predicting
sample labels, evaluating the accuracy of the AE. In addition, differentially expressed
genes (DEGs), signaling pathways, and transcription factors (TFs) involved in
immunosuppression and periodontitis were determined with an array of bioinformatics
analysis. Shared DEGs common to DEGs differentiating periodontitis from controls
and those differentiating the immune subtypes were considered as the key
immunosuppression genes in periodontitis.
Results: We produced representative molecular features and identified two immune
subtypes in periodontitis using an AE. Two subtypes were also predicted in the validation
set with the SVM classifier. Three “master” immunosuppression genes, PECAM1,
FCGR3A, and FOS were identified as candidates pivotal to immunosuppressive
mechanisms in periodontitis. Six transcription factors, NFKB1, FOS, JUN, HIF1A,
STAT5B, and STAT4, were identified as central to the TFs-DEGs interaction network.
The two immune subtypes were distinct in terms of their regulating pathways.
Conclusion: This study applied a DL-based AE for the first time to identify immune
subtypes of periodontitis and pivotal immunosuppression genes that discriminated
periodontitis from the healthy. Key signaling pathways and TF-target DEGs that
putatively mediate immune suppression in periodontitis were identified. PECAM1,
FCGR3A, and FOS emerged as high-value biomarkers and candidate therapeutic
targets for periodontitis
Deep Learning Reveals Key Immunosuppression Genes and Distinct Immunotypes in Periodontitis
Background: Periodontitis is a chronic immuno-inflammatory disease characterized by inflammatory destruction of tooth-supporting tissues. Its pathogenesis involves a dysregulated local host immune response that is ineffective in combating microbial challenges. An integrated investigation of genes involved in mediating immune response suppression in periodontitis, based on multiple studies, can reveal genes pivotal to periodontitis pathogenesis. Here, we aimed to apply a deep learning (DL)-based autoencoder (AE) for predicting immunosuppression genes involved in periodontitis by integrating multiples omics datasets.
Methods: Two periodontitis-related GEO transcriptomic datasets (GSE16134 and GSE10334) and immunosuppression genes identified from DisGeNET and HisgAtlas were included. Immunosuppression genes related to periodontitis in GSE16134 were used as input to build an AE, to identify the top disease-representative immunosuppression gene features. Using K-means clustering and ANOVA, immune subtype labels were assigned to disease samples and a support vector machine (SVM) classifier was constructed. This classifier was applied to a validation set (Immunosuppression genes related to periodontitis in GSE10334) for predicting sample labels, evaluating the accuracy of the AE. In addition, differentially expressed genes (DEGs), signaling pathways, and transcription factors (TFs) involved in immunosuppression and periodontitis were determined with an array of bioinformatics analysis. Shared DEGs common to DEGs differentiating periodontitis from controls and those differentiating the immune subtypes were considered as the key immunosuppression genes in periodontitis.
Results: We produced representative molecular features and identified two immune subtypes in periodontitis using an AE. Two subtypes were also predicted in the validation set with the SVM classifier. Three “master” immunosuppression genes, PECAM1, FCGR3A, and FOS were identified as candidates pivotal to immunosuppressive mechanisms in periodontitis. Six transcription factors, NFKB1, FOS, JUN, HIF1A, STAT5B, and STAT4, were identified as central to the TFs-DEGs interaction network. The two immune subtypes were distinct in terms of their regulating pathways.
Conclusion: This study applied a DL-based AE for the first time to identify immune subtypes of periodontitis and pivotal immunosuppression genes that discriminated periodontitis from the healthy. Key signaling pathways and TF-target DEGs that putatively mediate immune suppression in periodontitis were identified. PECAM1, FCGR3A, and FOS emerged as high-value biomarkers and candidate therapeutic targets for periodontitis
Study on Micro Production Mechanism of Corner Residual Oil after Polymer Flooding
To study the microscopic production mechanism of corner residual oil after polymer flooding, microscopic visualization oil displacement technology and COMSOL finite element numerical simulation methods were used. The influence of the viscosity and interfacial tension of the oil displacement system after polymer flooding on the movement mechanism of the corner residual oil was studied. The results show that by increasing the viscosity of the polymer, a portion of the microscopic remaining oil in the corner of the oil-wet property can be moved whereas that in the corner of the water-wet property cannot be moved at all. To move the microscopic remaining oil in the corners with water-wet properties after polymer flooding, the viscosity of the displacement fluid or the displacement speed must be increased by 100–1000 times. Decreasing the interfacial tension of the oil displacement system changed the wettability of the corner residual oil, thus increasing the wetting angle. When the interfacial tension level reached 10−2 mN/m, the degree of movement of the remaining oil in the corner reached a maximum. If the interfacial tension is reduced, the degree of production of the residual oil in the corner does not change significantly. The microscopic production mechanism of the corner residual oil after polymer flooding expands the scope of the displacement streamlines in the corner
Predicting Tunnel Squeezing Using Multiclass Support Vector Machines
Tunnel squeezing is one of the major geological disasters that often occur during the construction of tunnels in weak rock masses subjected to high in situ stresses. It could cause shield jamming, budget overruns, and construction delays and could even lead to tunnel instability and casualties. Therefore, accurate prediction or identification of tunnel squeezing is extremely important in the design and construction of tunnels. This study presents a modified application of a multiclass support vector machine (SVM) to predict tunnel squeezing based on four parameters, that is, diameter (D), buried depth (H), support stiffness (K), and rock tunneling quality index (Q). We compiled a database from the literature, including 117 case histories obtained from different countries such as India, Nepal, and Bhutan, to train the multiclass SVM model. The proposed model was validated using 8-fold cross validation, and the average error percentage was approximately 11.87%. Compared with existing approaches, the proposed multiclass SVM model yields a better performance in predictive accuracy. More importantly, one could estimate the severity of potential squeezing problems based on the predicted squeezing categories/classes
Review of Diagnosis Technique for Equipment Faults and its Development Trend
Modern control system is becoming larger and more complicated with each passing day and the possibility of system breakdown increases with it, so people eagerly need to set up fault diagnosis system to conduct real-time monitoring and fault diagnosis for production system and take necessary measures to improve its overall reliability and maintainability. This paper states the principles and basic approaches of diagnosis technique for equipment faults, introduces development phrase of fault diagnosis technique and points out future development trend in this field
Study on the Manifold Cover Lagrangian Integral Point Method Based on Barycentric Interpolation
To achieve numerical simulation of large deformation evolution processes in underground engineering, the barycentric interpolation test function is established in this paper based on the manifold cover idea. A large-deformation numerical simulation method is proposed by the double discrete method with the fixed Euler background mesh and moving material points, with discontinuous damage processes implemented by continuous simulation. The material particles are also the integration points. This method is called the manifold cover Lagrangian integral point method based on barycentric interpolation. The method uses the Euler mesh as the background integral mesh and describes the deformation behavior of macroscopic objects through the motion of particles between meshes. Therefore, this method can avoid the problem of computation termination caused by the distortion of the mesh in the calculation process. In addition, this method can keep material particles moving without limits in the set region, which makes it suitable for simulating large deformation and collapse problems in geotechnical engineering. Taking a typical slope as an example, the results of a slope slip surface obtained using the manifold cover Lagrangian integral point method based on barycentric interpolation proposed in this paper were basically consistent with the theoretical analytical method. Hence, the correctness of the method was verified. The method was then applied for simulating the collapse process of the side slope, thereby confirming the feasibility of the method for computing large deformations
Study on Morphological Identification of Tight Oil Reservoir Residual Oil after Water Flooding in Secondary Oil Layers Based on Convolution Neural Network
In this paper, a microscopic oil displacement visualization experiment based on the glass etching model to simulate the tight oil reservoir of underground rocks is carried out. At present, water flooding technology is widely used in the development of oil and gas fields, and the remaining oil content is still very high after water flooding. It is the key to improving oil recovery to identify and study the remaining oil form distribution after water flooding. The experiment result shows there are five types of residual oil after water flooding: columnar residual oil, membranous residual oil, oil droplet residual oil, blind terminal residual oil and cluster residual oil. A convolution neural network is suitable for complex image characteristics with good robustness. In recent years, it has made a breakthrough in a set of small and efficient neural networks with SqueezeNet, Google Inception and the flattened network method put forward. In order to solve the problems of low automation, low efficiency and high error rate in the traditional remaining oil form recognition algorithm after water flooding in tight oil reservoirs, an image recognition algorithm based on the MobileNets convolutional neural network model was proposed in this paper to achieve accurate recognition of the remaining oil form. Based on traditional image processing methods which, respectively, extracted the whole picture of the different types of remaining oil in the image block, it uses the MobileNets network structure to classify different types of image block and realizes the layered depth convolution neural network system. The experiment result shows that the model can accurately identify the remaining oil forms, and the overall recognition accuracy is up to 83.8% after the convergence of the network model, which infinitely identifies the remaining oil forms in the morphological library, proving the strong generalization and robustness of the model