This paper describes a new simple speed estimator using fuzzy logic for improving the motor drive performance at low speed with low-resolution encoder. Since using fuzzy algorithm, the proposed technique requires no s...
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ISBN:
(纸本)0780352939
This paper describes a new simple speed estimator using fuzzy logic for improving the motor drive performance at low speed with low-resolution encoder. Since using fuzzy algorithm, the proposed technique requires no system parameter or assumption for speed estimation. Through the simulation and experiments, the proposed scheme enables to drive the motor at 25 rpm.
Using Calcium Carbonate (CaCO3)to improve waterflood conformance is a new concept that was borrowed from drilling operations, in which sized CaCO3 particles are routinely used to prevent lost circulation. The applicat...
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ISBN:
(纸本)9781613999806
Using Calcium Carbonate (CaCO3)to improve waterflood conformance is a new concept that was borrowed from drilling operations, in which sized CaCO3 particles are routinely used to prevent lost circulation. The application for water shutoff is to inject a predesigned volume of CaCO3 particles to reduce the permeability contrast between the fractures and the matrix, thereby improving the injection conformance to achieve better waterflood sweep efficiency. The journey of developing this new conformance technology started in early 2021 by working with a vendor to redesign a bridging agent used for drilling fluid losses into a simpler, less expensive recipe comprising CaCO3 particles with different sizes and a friction reducer to suspend and carry the particles deep into the formation. This technology features several key advantages: low-cost rigless operation, a flexible recipe for materials of different sizes, the volumes and pumping schedule can be adjusted, and the treatment is reversible in case of a blockage. The first campaign of implementing this technology was successfully completed in January 2022. Three water injectors were treated in the Safah field in Oman, a mature waterflood with an area with high water cuts and low recovery factors. A drop in injectivity was seen after pumping a total of 300 bbl of the two sizes of CaCO3 particles (600 micron and 150 micron), indicating that the treatment achieved the objective. After logging one of the injectors and comparing the injection profile before and after the treatment, we found a clear improvement at the heel section of the openhole horizontal lateral. Injectivity in the thief zone was reduced from 99% to 62% at the heel section, and injectivity at the middle of the lateral improved by 38%. To date, four separate campaigns of this new injection conformance treatment have been executed targeting a total of 16 water injectors. Excellent operational success of 93% has been achieved, with a significant drop in injec
Monitoring of animals in the wild using camera traps is one of the promising ways for monitoring animal behaviour and estimation of dynamic of changes in natural systems over the large areas. The installation of camer...
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ISBN:
(纸本)9789532330984
Monitoring of animals in the wild using camera traps is one of the promising ways for monitoring animal behaviour and estimation of dynamic of changes in natural systems over the large areas. The installation of camera traps in a predefined place such as animal shelters, trails, watering places provides unique information that is not available by applying other monitoring methods. Present, a lot of methods and algorithms have been developed that allow us to recognize the natural images taking into account the variability of shooting conditions, illumination, location and posture of the animal, as well as a complex textural background, representing various states of the forest, steppe, mountain and tundra landscapes. This paper presents the results of analysis and systematization of monitoring data from images obtained on the protected natural territories in the Krasnoyarsk region. The authors propose the special structure of a centralized data warehouse for an intelligent ecosystem monitoring system. The structure of the data warehouse combines historical, operational and reference data. The content of structural elements of the data warehouse is described in detail. The developed data warehouse combines monitoring data from different sources and makes up a united informational resource for further data processing and solving analytical tasks of environmental monitoring.
Cyber fraud causes significant losses to the economy and has become a lucrative form of illicit business by leveraging the Internet as a communication channel. Criminals in the cyber fraud underground economy use onli...
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ISBN:
(纸本)9781509038657
Cyber fraud causes significant losses to the economy and has become a lucrative form of illicit business by leveraging the Internet as a communication channel. Criminals in the cyber fraud underground economy use online underground marketplaces and other forms of social media to exchange information and trade stolen information. Analyzing these underground marketplaces is challenging due to the variability of both members and marketplaces. To understand more about the underground economy and the actors in it, we propose a topic-based social network analysis and clustering approach to identify the key members and their roles in the cyber fraud value chain. An experiment is conducted using data from several online underground marketplaces in China. Results suggest that the proposed method can aid in identifying key members in terms of roles, influence levels, and their social relationships.
This paper presents computer software developed for rating and optimum selection of finned circular tubes compact heat exchangers with various coil geometries. The software is developed to use as a computing tool for ...
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The circular Escherichia coli chromosome has been suggested to form a partition of the genome where it folds into a collection of sequentially consecutive *** paper presents a prediction method to give the location of...
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ISBN:
(纸本)9781538629185
The circular Escherichia coli chromosome has been suggested to form a partition of the genome where it folds into a collection of sequentially consecutive *** paper presents a prediction method to give the location of the folding *** genes involved in one domain tend to be co-expressed,the information of activation and co-expression level is extracted from multi-source data *** activation level of genes is described by frequencies of attending the pathways in different database,while Intensity Co-expression is defined for co-expression *** two types of data are processed by wavelet analysis and are used to improve the optimization model for *** objective function of this model is to minimize both the total number of unfoldings of these domains in the chromosome and total frequencies of folding *** multi-source information is also designed for the experimental *** experiment results show the good effect of the prediction method in Computational Biology.
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