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41.
Andras Ferencz Erik G. Learned-Miller Jitendra Malik 《International Journal of Computer Vision》2008,77(1-3):3-24
Object identification is a specialized type of recognition in which the category (e.g. cars) is known and the goal is to recognize
an object’s exact identity (e.g. Bob’s BMW). Two special challenges characterize object identification. First, inter-object
variation is often small (many cars look alike) and may be dwarfed by illumination or pose changes. Second, there may be many
different instances of the category but few or just one positive “training” examples per object instance. Because variation
among object instances may be small, a solution must locate possibly subtle object-specific salient features, like a door
handle, while avoiding distracting ones such as specular highlights. With just one training example per object instance, however,
standard modeling and feature selection techniques cannot be used. We describe an on-line algorithm that takes one image from
a known category and builds an efficient “same” versus “different” classification cascade by predicting the most discriminative
features for that object instance. Our method not only estimates the saliency and scoring function for each candidate feature,
but also models the dependency between features, building an ordered sequence of discriminative features specific to the given
image. Learned stopping thresholds make the identifier very efficient. To make this possible, category-specific characteristics
are learned automatically in an off-line training procedure from labeled image pairs of the category. Our method, using the
same algorithm for both cars and faces, outperforms a wide variety of other methods. 相似文献
42.
43.
Data-driven next-generation smart grid towards sustainable energy evolution: techniques and technology review
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Faiaz Ahsan Nazia Hasan Dan Subrata K. Sarker Li Li S. M. Muyeen Md. Firoj Ali Zinat Tasneem Md. Mehedi Hasan Sarafat Hussain Abhi Md. Robiul Islam Md. Hafz Ahame Md. Manirul Islam Sajal K. Das Md. Faisal R. Badal Prangon Das 《电力系统保护与控制》2023,8(3):696-737
Meteorological changes urge engineering communities to look for sustainable and clean energy technologies to keep the environment safe by reducing CO2 emissions. The structure of these technologies relies on the deep integration of advanced data-driven techniques which can ensure efcient energy generation, transmission, and distribution. After conducting thorough research for more than a decade, the concept of the smart grid (SG) has emerged, and its practice around the world paves the ways for efcient use of reliable energy technology. However, many developing features evoke keen interest and their improvements can be regarded as the next-generation smart grid (NGSG). Also, to deal with the non-linearity and uncertainty, the emergence of data-driven NGSG technology can
become a great initiative to reduce the diverse impact of non-linearity. This paper exhibits the conceptual framework of NGSG by enabling some intelligent technical features to ensure its reliable operation, including intelligent control, agent-based energy conversion, edge computing for energy management, internet of things (IoT) enabled inverter, agent-oriented demand side management, etc. Also, a study on the development of data-driven NGSG is discussed to facilitate the use of emerging data-driven techniques (DDTs) for the sustainable operation of the SG. The prospects of DDTs in the NGSG and their adaptation challenges in real-time are also explored in this paper from various points of view including engineering, technology, et al. Finally, the trends of DDTs towards securing sustainable and clean energy evolution from the NGSG technology in order to keep the environment safe is also studied, while some major future issues are highlighted. This paper can ofer extended support for engineers and researchers in the context of data-driven technology and the SG. 相似文献
44.
Faisal Ahmed Carlos Rodríguez-Fernández Henry A. Fernandez Yi Zhang Abde Mayeen Shafi Md Gius Uddin Xiaoqi Cui Hoon Hahn Yoon Naveed Mehmood Andreas C. Liapis Lide Yao Humeyra Caglayan Zhipei Sun Harri Lipsanen 《Advanced functional materials》2023,33(33):2302051
Developing selective and coherent polymorphic crystals at the nanoscale offers a novel strategy for designing integrated architectures for photonic and optoelectronic applications such as metasurfaces, optical gratings, photodetectors, and image sensors. Here, a direct optical writing approach is demonstrated to deterministically create polymorphic 2D materials by locally inducing metallic 1T′-MoTe2 on the semiconducting 2H-MoTe2 host layer. In the polymorphic-engineered MoTe2, 2H- and 1T′- crystalline phases exhibit strong optical contrast from near-infrared to telecom-band ranges (1–1.5 µm), due to the change in the band structure and increase in surface roughness. Sevenfold enhancement of third harmonic generation intensity is realized with conversion efficiency (susceptibility) of ≈1.7 × 10−7 (1.1 × 10−19 m2 V−2) and ≈1.7 × 10−8 (0.3 × 10−19 m2 V−2) for 1T′ and 2H-MoTe2, respectively at telecom-band ultrafast pump laser. Lastly, based on polymorphic engineering on MoTe2, a Schottky photodiode with a high photoresponsivity of 90 AW−1 is demonstrated. This study proposes facile polymorphic engineered structures that will greatly benefit realizing integrated photonics and optoelectronic circuits. 相似文献
45.
Faisal Bahadur Arif Iqbal Umar Insaf Ullah Fahad Algarni Muhammad Asghar Khan 《计算机系统科学与工程》2022,42(2):589-604
Scalability is one of the most important quality attribute of software-intensive systems, because it maintains an effective performance parallel to the large fluctuating and sometimes unpredictable workload. In order to achieve scalability, thread pool system (TPS) (which is also known as executor service) has been used extensively as a middleware service in software-intensive systems. TPS optimization is a challenging problem that determines the optimal size of thread pool dynamically on runtime. In case of distributed-TPS (DTPS), another issue is the load balancing b/w available set of TPSs running at backend servers. Existing DTPSs are overloaded either due to an inappropriate TPS optimization strategy at backend servers or improper load balancing scheme that cannot quickly recover an overload. Consequently, the performance of software-intensive system is suffered. Thus, in this paper, we propose a new DTPS that follows the collaborative round robin load balancing that has the effect of a double-edge sword. On the one hand, it effectively performs the load balancing (in case of overload situation) among available TPSs by a fast overload recovery procedure that decelerates the load on the overloaded TPSs up to their capacities and shifts the remaining load towards other gracefully running TPSs. And on the other hand, its robust load deceleration technique which is applied to an overloaded TPS sets an appropriate upper bound of thread pool size, because the pool size in each TPS is kept equal to the request rate on it, hence dynamically optimizes TPS. We evaluated the results of the proposed system against state of the art DTPSs by a client-server based simulator and found that our system outperformed by sustaining smaller response times. 相似文献
46.
Computational Economics - This study tries to unravel the stock market prediction puzzle using the textual analytic with the help of natural language processing (NLP) techniques and Deep-learning... 相似文献
47.
Munsif Ali Jatoi Nidal Kamel Aamir Saeed Malik Ibrahima Faye Jose M. Bornot Tahamina Begum 《International journal of imaging systems and technology》2016,26(1):55-64
Electroencephalography (EEG) is widely used in variety of research and clinical applications which includes the localization of active brain sources. Brain source localization provides useful information to understand the brain's behavior and cognitive analysis. Various source localization algorithms have been developed to determine the exact locations of the active brain sources due to which electromagnetic activity is generated in brain. These algorithms are based on digital filtering, 3D imaging, array signal processing and Bayesian approaches. According to the spatial resolution provided, the algorithms are categorized as either low resolution methods or high resolution methods. In this research study, EEG data is collected by providing visual stimulus to healthy subjects. FDM is used for head modelling to solve forward problem. The low‐resolution brain electromagnetic tomography (LORETA) and standardized LORETA (sLORETA) have been used as inverse modelling methods to localize the active regions in the brain during the stimulus provided. The results are produced in the form of MRI images. The tables are also provided to describe the intensity levels for estimated current level for the inverse methods used. The higher current value or intensity level shows the higher electromagnetic activity for a particular source at certain time instant. Thus, the results obtained demonstrate that standardized method which is based on second order Laplacian (sLORETA) in conjunction with finite difference method (FDM) as head modelling technique outperforms other methods in terms of source estimation as it has higher current level and thus, current density (J) for an area as compared to others. 相似文献
48.
Muhammad Faisal Michael B. C. Khoo Ayesha Nayab Raja Fawad Zafar 《Quality and Reliability Engineering International》2023,39(1):472-477
Link relative-based approach was used in an article (see reference 1) to enhance the performance of the cumulative sum (CUSUM) control chart. This technique involves the use of firstly, the link relative variable to convert the process observations in a relative to the mean form and secondly, optimal constants to define a new variable which is used as the plotting statistic of the link relative CUSUM chart. In this article, it is proven through simulation study that the optimal constants with fixed values, as reported in the aforementioned article, give different results. Instead, if the regression technique is used, then the same results will be obtained. 相似文献
49.
K. Malik F. Ahmad N. A. Yunus T. Nakato E. Mouri S. Dawood I. R. Memon 《Materialwissenschaft und Werkstofftechnik》2023,54(9):1157-1166
This research aims to develop a method for the amalgamation of graphene nanoplatelets in glass/epoxy composites. The poor interface bonding between the fiber and matrix is critical and hinders the full performance of the composites. Glass fabric and epoxy were used as reinforcement and matrix in the composite, respectively. Graphene nanoplatelets were utilized as an additional nano-materials filler for the composites. Glass/graphene/epoxy and glass/epoxy composites were fabricated via vacuum infusion molding. The new method of applying graphene nanoplatelets as secondary reinforcement in the composite was developed based on proper functionalization in the sonication process. The physical, tensile, flexural, and short beam interlaminar properties of fabricated composites were examined to analyze the method's effectiveness. The results showed that density decreased by around 5 %; however, thickness increased by around 34 % after introducing graphene nanoplatelets into the composites. The tensile strength and modulus of the composites declined by approximately 19 %, on the other hand, flexural strength and modulus increased by around 63.3 % and 8.3 %, respectively, after the addition of graphene nanoplatelets into the composites. Moreover, interlaminar shear strength of the composite was enhanced by approximately 50 %. 相似文献
50.
Flynn Castles Stephen M. Morris Damian J. Gardiner Qasim M. Malik Harry J. Coles 《Journal of the Society for Information Display》2010,18(2):128-133
Abstract— The flexoelectro‐optic effect provides a fast‐switching mechanism (0.01–0.1 msec), suitable for use in field‐sequential‐color full‐motion‐video displays. An in‐plane electric field is applied to a short‐pitch chiral nematic liquid crystal aligned in the uniform standing helix (or Grandjean) texture. The switching mechanism is experimentally demonstrated in a single‐pixel test cell, and the display performance is investigated as a function of device parameters. A contrast ratio of 2000:1 is predicted. 相似文献