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This study investigates use of acoustic signals to detect cracks in polyvinyl chloride (PVC) sewer pipes. Cracked sewer pipes can result in release of untreated human and industrial waste, toxic materials and debris affecting human health and the environment. The released toxic effluents can pollute water reservoirs and damage public and private property. Polyvinyl Chloride (PVC) pipes have been extensively...
World Wide Web has become the major source of information dissemination. Due to its vast expansion and heterogeneity, users faces difficulty in finding relevant results quickly. Ranking is an important application of web mining which is based on the structure, content and usage. Many algorithms exist for web page ranking and these algorithms are based upon one or more parameters such as forward links,...
As for the synchronization control of double winches of large crawler cranes, a master-slave PI control strategy with the hook's inclination as feedback signal is proposed and analyzed. The transfer function of the pump-controlled dual-winch system is obtained by building the mathematical model and linearizing it around the working point and thus the stability and steady-state error are analyzed....
This paper describes the mathematical model of the suspension of a robot traction of crawler type, in order to reduce mechanical vibrations caused by operation of the motors and overcoming obstacles in a path. The analysis in reference becomes relevant to the extent that the mechanical vibrations generated damage to the structure and electronic elements in this when the natural frequency of them is...
Web services are currently one of the preferred ways for realizing Service Oriented Architectures in business systems. Due to this popularity and also due partly to the failure of the Universal Business Registry initiative, the number of published service descriptions openly available on the Web has increased by a large extent and hence, relevant service discovery as per user specification remains...
Crawler robot has been used widely in many areas because of its excellent adaptation for all kinds of complex terrain. As one of automatic control methods for the trajectory trace of robot, sliding mode control has advantages over others because of its non-sensitivity and capability of quick response when the system parameters change, it will be used in this paper for the trace of trajectory. To begin...
For performing the best obstacle-surmounting capability, including Stairs-Climbing and channel-crossing, SHU-I's, a six-track robot with four independent swing arms, obstacle-surmounting capability are analyzed according to the robot kinematics based on the obstacle-surmounting mechanism of the six-track robot with four swing arms. Its maximal obstacle-surmounting capability of Stairs-Climbing is...
This paper describes a remote control system for a crawler-type mobile robot with a passive sub-crawler. Such a system is greatly advantageous because it has an essentially compliant mechanism in that the sub-crawler angle can be adapted to a road surface shape. Its operation is extremely simple, and it is only necessary to control the movement direction and driving speed in comparison with the case...
Due to the dynamic nature of the web plenty of webpages are deleted and added newly and as the web is large collection of data in form of the webpages or in the group of webpages as websites. So every time a surfer searches the web using the search engine, the data should be fresh and relevant. Due to the large size of web, corresponding to any query made by the user number of pages are being retrieved...
<?Pub Dtl?>A crawler system has the potential to expand research and development on seafloors with irregular steep terrain and sand. Characteristic parameters in water, such as added mass, buoyancy, and hydrodynamic forces, considerably affect and decrease the mobility of crawler-type remotely operated vehicles (ROVs). To study and evaluate the mobile performance of a crawler system, it is important...
This paper introduces a topic specific web crawling system, which gathers basic educational resources from the web, and indexes them for the purpose of basic educational users. Compared to other similar theme based crawling system, the crawler integrates fuzzy rule based algorithm and VSM text analysis technology together to predicting each URL's relevancy to basic education while parsing current...
A crawler system as a mobility function on the seafloor has the possibility to expand the activity of research and development on the irregular terrain and the sand seafloor. Investigation of equilibrium running dynamic and motion such as a slip of the crawler type ROV is of importance to realize the activity there because characteristic parameters in water such as buoyancy and hydrodynamic forces...
A web crawler is defined as an automated program that methodically scans through Internet pages and downloads any page that can be reached via links. With the exponential growth of the Web, fetching information about a special-topic is gaining importance. A focused crawler is a web crawler that attempts to download only web pages that are relevant to a predefined topic or set of topics. In order to...
A crawler system as a mobility function on the seafloor has the possibility to expand the activity of research and development on the irregular terrain and on the sand seafloor. To improve the mobility function, a flipper-type crawler system was developed. In addition, the dynamic motion of the crawler system investigation is important to realize the activity there because characteristic parameters...
Semantic focused crawler computes the priority of pages crawling by web page semantic similarity with topic which is defined by ontology. Ontology is a new approach referred to as the main pivot of change from the present web to a new web called semantic web. The main problem about focused crawlers is to find a computation function of appropriate relevance based on which the crawler can estimate the...
Mobility characteristic of ROV with crawler system in steady running was theoretically and experimentally investigated. It was found experimentally that flipper type crawler system gave advantages when running on the irregular seafloor and when working on the seafloor. On the other hand, the experiment suggests that the static or quasi-static analysis is not enough to estimate the motion of ROV with...
Employing a parallel crawler as a multi processes crawler causes different issues of concern in comparison to applying a single-process crawler. These issues impact on achieving the results with higher or even the same quality from a parallel crawler in comparison to a centralized one. Existed parallel crawlers' architectures employ link dependant metrics - such as Backlink count or PageRank - for...
In this paper we propose a novel optimal crawling strategy for next-generation multimedia search engines. We consider here a Web crawl as a two-dimensional (2D) random walker on a graph whose vertices are the Web pages and whose edges are the hyperlinks. The proposed crawler is a two-part scheme optimizing the crawling process in such a way that the average level of staleness over all pages is minimized...
Deep Web has been an important resource on the Web due to its rich and high quality information, leading to emerging a new application area in data mining and integrates. There may be hundreds or thousands of data sources providing data of relevance to a particular domain on the Web, So a primary challenge to large-scale deep Web data integration is to determine in what order to user integrate candidate...
In order to reduce a tension on a cable, a deep sea ROV is designed to minimize the weight. However, the ROV having a lightweight is apt to wheelie when running by means of a crawler system. In order to run stably in counterpoise the combination of the center of gravity and the center of buoyancy should be in an adequate area called ldquostable areardquo which can be obtained corresponding to the...
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