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Pulp and Paper from Sugarcane: Properties of Rind and Core Fractions
Full text linkTwo distinct lignocellulosic fractions (rind and core) can be obtained through a physical separation of sugarcane stalks. Although presenting differences in morphology, both fractions can be employed to produce pulps and papers. The pulps and paper sheets produced from the core and rind fractions were characterized by their chemical composition, physical properties and mechanical properties. The pulps obtained from the core presented a higher amount of fines, lower drainage ability and rendered denser and stiffer sheets. The pulps from the rind, which have a higher content of fibers and higher degree of polymerization, produced sheets with higher air permeability and water absorption. Both paper sheets presented mechanical and physical properties comparable to commercial papers and papers from different cellulosic sources. The different properties exhibited by the papers produced from each fraction allow their use for distinct purposes, and expands the opportunities in the context of sugarcane biorefinery
Enzymatic Hydrolysis of Sugarcane Biomass and Heat Integration as Enhancers of Ethanol Production
Full text linkThe aim of this study is to assess the possibility of increasing ethanol production by introducing the bagasse hydrolysis process into conventional distilleries. Simulations were performed for mass and energy balances using Aspen Plus® software. It was assumed that sugarcane trash and lignin cake—hydrolysis process residues—are available as supplementary fuel. Several cases were evaluated, including: (a) conventional ethanol distillery, (b) conventional plant combined with a hydrolysis process without heat integration, with different solid contents in the hydrolysis reactor, and (c) conventional plant combined with the hydrolysis process applying heat integration by pinch analysis. The highest ethanol yield was achieved in the case of heat integration and concentration of cellulose hydrolysate by the membrane system with a solid content of 5% in the hydrolysis reactor. This represents an increase of 22% over conventional distilleries currently found in the industry
Preservation Mechanism of Network Electronic Records Based on Broadcast-Storage Network in Urban Construction
Full text linkWith the wide application of information technology in urban infrastructure, urban construction has entered the stage of smart city, forming a large number of network electronic records. These electronic records play a vital role in the maintenance of urban infrastructure. However, how to preserve the network electronic records in the field of urban construction is still lack of a comprehensive and serious study. Aiming at this problem, the paper proposes to use the technology of broadcast-storage network to preserve the network electronic records for a long time and gives the concrete preservation process
An Influence Maximization Algorithm Based on the Influence Propagation Range of Nodes
No full textThe problem of influence maximization in the social network G is to find k seed nodes with the maximum influence. The seed set S has a wider range of influence in the social network G than other same-size node sets. The influence of a node is usually established by using the IC model (Independent Cascade model) with a considerable amount of Monte Carlo simulations used to approximate the influence of the node. In addition, an approximate effect (1-1/e) is obtained, when the number of Monte Carlo simulations is 10000 and the probability of propagation is very small. In this paper, we analyze that the propagative range of influence of node set is limited in the IC model, and we find that the influence of node only spread to the t'-th neighbor. Therefore, we propose a greedy algorithm based on the improved IC model that we only consider the influence in the t’-th neighbor of node. Finally, we perform experiments on 10 real social network and achieve favorable results
Research on Robot Control Technology Based on Vision Localization
No full textBased on the understanding of machine vision localization technology at home and abroad, this paper outlines the overall design of the system, and analyses the working principle and workflow of the robot with vision system in workpiece grinding. The hardware design of the system is introduced. The process of image processing is analyzed in detail, and the results of image processing are given. The basic parameters of camera imaging are taken as internal parameters. The camera calibration is obtained by rotation matrix R and translation parameter T. The coordinate transformation of camera coordinate system and world coordinate system is analyzed. Finally, the positions and postures of the actual workpiece and the end-effector in the world coordinate system are given respectively, and the robot with the vision system is used to grasp the actual workpiece. The difficulties of this project are visual calibration, image processing and coordinate transformation. Robot vision technology can directly grasp the location. Compared with the manual mechanical positioning, the robot that realizes autonomous vision localization has more flexibility, better quality and higher efficiency
Multi-Layer Graph Generative Model Using AutoEncoder for Recommendation Systems
No full textGiven the glut of information on the web, it is crucially important to have a system, which will parse the information appropriately and recommend users with relevant information, this class of systems is known as Recommendation Systems (RS)-it is one of the most extensively used systems on the web today. Recently, Deep Learning (DL) models are being used to generate recommendations, as it has shown state-of-the-art (SoTA) results in the field of Speech Recognition and Computer Vision in the last decade. However, the RS is a much harder problem, as the central variable in the recommendation system’s environment is the chaotic nature of the human’s purchasing/consuming behaviors and their interest. These user-item interactions cannot be fully represented in the Euclidean-Space, as it will trivialize the interaction and undermine the implicit interactions patterns. So to preserve the implicit as well as explicit interactions of user and items, we propose a new graph based recommendation framework. The fundamental idea behind this framework is not only to generate the recommendations in the unsupervised fashion but to learn the dynamics of the graph and predict the short and long term interest of the users. In this paper, we propose the first step, a heuristic multi-layer high-dimensional graph which preserves the implicit and explicit interactions between users and items using SoTA Deep Learning models such as AutoEncoders. To generate recommendation from this generated graph a new class of neural network architecture-Graph Neural Network-can be used
Application of Ontology in the Web Information Retrieval
No full textIn this paper, the research advances of ontology and its application are reviewed firstly. With the development of ontology technology, subject-oriented web information retrieval technology combining ontology has been becoming one of the hot scientific issues. The innovative method of the semantic web technology combined with the traditional information retrieval technology is put forward, and the related algorithm based on ontology for judging the relevancy with different topics is also represented, and has proved to be effective in given experiments
Multiscale Hybrid-Mixed Finite Element Method for Flow Simulation in Fractured Porous Media
No full textThe multiscale hybrid-mixed (MHM) method is applied to the numerical approximation of two-dimensional matrix fluid flow in porous media with fractures. The two-dimensional fluid flow in the reservoir and the one-dimensional flow in the discrete fractures are approximated using mixed finite elements. The coupling of the two-dimensional matrix flow with the one-dimensional fracture flow is enforced using the pressure of the one-dimensional flow as a Lagrange multiplier to express the conservation of fluid transfer between the fracture flow and the divergence of the one-dimensional fracture flux. A zero-dimensional pressure (point element) is used to express conservation of mass where fractures intersect. The issuing simulation is then reduced using the MHM method leading to accurate results with a very reduced number of global equations. A general system was developed where fracture geometries and conductivities are specified in an input file and meshes are generated using the public domain mesh generator GMsh. Several test cases illustrate the effectiveness of the proposed approach by comparing the multiscale results with direct simulations
Exploring Urban Population Forecasting and Spatial Distribution Modeling with Artificial Intelligence Technology
No full textThe high precision population forecasting and spatial distribution modeling are very important for the theory and application of population sociology, city planning and Geo-Informatics. However, the two problems need to be solved for providing the high precision population information. One is how to improve the population forecasting precision of small area (e.g., street scale); another is how to improve the spatial resolution of urban population distribution model. To solve the two problems, some new methods are proposed in this contribution. (1) To improve the precision of small area population forecasting, a new method is developed based on the fade factor and the slide window. (2) To improve the spatial resolution of urban population distribution model, a new method is proposed based on the land classification, public facility information and the artificial intelligence technology. For validation of the proposed methods, the real population data of 15 streets in Xicheng district, Beijing, China from 2010 to 2016, the remote sensing images and the public facility data are collected and used. A number of experiments are performed. The results show that the spatial resolution of proposed model reaches 30m*30m and the forecasting precision is better than 5% using the proposed method to forecast the population of 15 streets in Xicheng district in the next four years
