Entity

Time filter

Source Type


Sun G.,China University of Petroleum - Beijing | Li H.,China University of Petroleum - Beijing | Huang H.,Daqing Oilfield Engineering Co
Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu | Year: 2016

Purpose: The traditional K-means algorithm requires the K value, and it is sensitive to the initial clustering center. Different initial clustering centers often correspond to the different clustering results, and the K value is always required. Aiming at these shortcomings, the article proposes a method for getting the clustering center based on the density and max-min distance means. The selection of the clustering center and classification can be carried out simultaneously. Methodology: According to the densities of objects, the noise was eliminated and the densest object was selected as the first clustering center. The max-min distance method was used to search the other best cluster centers, at the same time, the cluster, which the object belongs to, was decided. Findings: Clustering results are related to the selection of parameters θ. If the sample distribution is unknown, only test method can be used through multiple test optimization. With prior knowledge for the selection of θ, it can be converged quickly. Therefore, θ should be optimized. Originality: This article proposes the new method based on the density to get the first initial clustering center, and then the new method based on the maximum and minimum value. The improved algorithm obtained through experimental analysis insures higher and stable accuracy. Practical value: The experiments showed that the algorithm allows for automatic obtaining of the k clustering centers and have a higher clustering accuracy in unknown datasets processing. © Guangbin Sun, Hongqi Li, Haiying Huang, 2016. Source


Sun G.,Daqing Oilfield Engineering Co | Li H.,China University of Petroleum - Beijing
Metallurgical and Mining Industry | Year: 2015

So far the centralized operation and maintenance monitoring for equipments is difficult to meet the needs in the applications of the enterprises which have complex business systems. This essay provides a business-oriented operation monitoring system that based on the technology of Keepalived and Inotify and the key process state judgment switch condition as well as triggered the synchronization process by changing the main file attribute to implement the redundant distributed monitoring mode. Integrated the business model into the logic relation of monitoring resources and treated the business view for analysis of system statements have been designed to improve the localization rate of alarming problems. The experimental results show that this system with a certain reference value for engineering application is characterized by its basic data acquisition which has low cost and small interference and meets the real-time monitoring for the complex business resources of the data center. Source


Liu G.,Daqing Oilfield Engineering Co | Wang X.,Daqing Petrochemical Company
Shiyou Huagong/Petrochemical Technology | Year: 2014

The structure-activity relationship and hydration mechanism of ionic liquid Gemini imidazolium surfactant(ILGIS) aqueous solutions were studied using the topology system. The results showed that there was interaction between the hydrophobic alkyl tail chains of the surfactant molecules and the total electric charge of the polar groups, and the both increased remarkably with the increase of the length of linking groups. Under the condition of the water molecule number 1-3, ILGIS and water formed hydrate clusters with the ratio of ILGIS to water 1:1. As the water molecule number increased to 4 or 5, ring and cage hydrate clusters formed with the ratios 1:2 and 2:2. There were electrostatic repulsion among the aggregation of the hydrophobic groups due to the negative charge in the alkyl chain ends. As the surfactant concentration was low, the electrostatic repulsion in the system could be ignored. The influence of the electrostatic repulsion was enhanced with increasing the ILGIS concentration, which was unfavourable to the micellization. Source


Yu C.,CAS Wuhan Institute of Rock and Soil Mechanics | Li G.,Daqing Oilfield Engineering Co | Xia X.,CAS Wuhan Institute of Rock and Soil Mechanics | Zhou Q.,CAS Wuhan Institute of Rock and Soil Mechanics
Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | Year: 2013

In order to study the effects of rock excavation unloading and adjacent blasting on jointed rock and support structure, based on discrete element method, static and dynamic supporting analyses are carried out for Dalian underground oil storage cavern local jointed rock masses. Firstly, according to alternative support schemes, static supporting analysis of rock excavation is carried out, and the surrounding rock stress field and displacement field are obtained. Simultaneity, feasibility and improvements of alternative support schemes are studied. Then, considering adjacent region blast vibration, the equivalent blasting load derived from field test results is applied. The dynamic supporting effect of adjacent blasting vibration is analyzed. The time curve of monitoring points and the variations of velocity, stress and displacement are got. The numerical calculation method has certain reference value for static, dynamic analysis and determining safety blasting vibration standards. Source


An S.,Harbin Institute of Technology | Cui J.X.,Harbin Institute of Technology | Li L.Y.,Daqing Oilfield Engineering Co
IET Intelligent Transport Systems | Year: 2011

This study reports on the tentative use of a multi-agent micro-simulation framework to address the issue of assessing commuter behaviour's day-to-day dynamics under pre-trip information. A Bayesian updating model is adopted to capture the reasoning mechanism by which commuters update their travel time perceptions from one day to the next in light of information and their previous experience. The population of commuters is represented as a community of autonomous agents, and travel demand results from the decision-making deliberation performed by each individual of the population as regards route and departure time. The reasoning mechanism of commuters is modelled by means of a Belief, Desire and Intention architecture, which has been a central theme in the multi-agent systems literature since the early 1990s. Each part of this architecture is specified by a multi-agent programming language named as AgentSpeak (L). A simple simulation scenario was devised using a combination of Jason (a multi-agent simulator) and Paramics (a traffic simulator). The simulation results show that the overall performance of the system is very likely affected by exogenous information and personal travel experiences; also, accurate information can greatly affect driver's switching activities and improve daily commuting conditions. Moreover, the combination of micro-simulation and agent-based modelling technique shows a great potential to represent more realistic and more complex driver's behaviour under intelligent transport system environment. © 2011 The Institution of Engineering and Technology. Source

Discover hidden collaborations