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961.
The paper describes the accurate calibration of the camera transformation for a vision system consisting of a camera mounted on a robot. The calibration includes an analysis of the linearity of the camera. A knowledge of the camera transformation allows the three-dimensional position of the object points to be determined using triangulation. 相似文献
962.
In language learning, strong relationships between Gold-style models and query models have recently been observed: in some quite general setting Gold-style learners can be replaced by query learners and vice versa, without loss of learning capabilities. These ‘equalities’ hold in the context of learning indexable classes of recursive languages. 相似文献
963.
Agriculture-based precise and accurate information needs to be disseminated promptly to farmers so that better decisions such as managing farm fields, making continuous and scientific changes in their production systems and grabbing advantage of market opportunities can be made. In this paper, mobile technology is assessed for the agriculture information dissemination system. A survey has been conducted to find out potential technology, related to the use of the Internet and mobile among farmers in the state of Punjab in India, to deliver agriculture-related information to them. Results show that agricultural information system needs to be developed based on the mass communication technology such as mobile systems. It is also noted that localization and native language of farmers are the concerns to be incorporated into the systems. It has been focused that the use of soft-computing techniques in conjunction with communication networks, for inferring the decision regarding best practices for agricultural activities, is helpful in the development of these systems. 相似文献
964.
Sixty-nine maritally intact, middle-class Caucasian families rearing their 15-month-old firstborn male child participated in a study of fathering. Two 1-hr naturalistic home observations per family were conducted near dinnertime to record father-child interactions, which were then used to rate father involvement. Cluster analysis of fathering ratings revealed 4 groups of dads: caretakers, playmates-teachers, disciplinarians, and disengaged fathers. Information on demographics, personality, marital quality, relatedness, moods and hassles, and infant emotionality was gathered via parental reports. Analysis of antecedent variables indicated that the caretaker and playmate-teacher fathers were more educated, had more prestigious occupations, were less neurotic, had more confidence in the dependability of others, and experienced fewer daily hassles than the disciplinarian and disengaged fathers. Discriminant analysis demonstrated the collective ability of the antecedent variables to distinguish the 4 groups of fathers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Jain Praphula Kumar Pamula Rajendra Ansari Sarfraj 《Wireless Personal Communications》2021,118(4):2469-2485
Wireless Personal Communications - Consumers increasingly rely on online reviews to assist them in their buying decisions. The rising popularity of e-commerce websites, hotel reviews, and social... 相似文献
968.
Chouhan Siddharth Singh Singh Uday Pratap Jain Sanjeev 《Wireless Personal Communications》2021,121(3):1757-1779
Wireless Personal Communications - In recent years, the applications of the computer vision concepts and information communication technology has been observed in number of applications including... 相似文献
969.
Li‐ion cells are used for energy storage and conversion in electric vehicles and a variety of consumer devices such as hoverboards. Performance and safety of such devices are severely affected by overheating of Li‐ion cells in aggressive operating conditions. Multiple recent fires and accidents in hoverboards are known to have originated in the battery pack of the hoverboard. While thermal analysis and measurements have been carried out extensively on large battery packs for electric vehicles, there is relatively lesser research on smaller devices such as hoverboards, where the extremely limited thermal management design space and the critical importance of user safety result in severe thermal management challenges. This paper presents experimental measurements and numerical analysis of a novel approach for thermal management of the battery pack of a hoverboard. Measurements indicate that temperature rise in cells in the pack can be as large as 30°C at 4C discharge rate, which, although unlikely to be a standard discharge rate, may result from a malfunction or accident. A novel thermal management approach is investigated, wherein careful utilization of air flow generated by hoverboard motion is shown to result in significant temperature reduction. Measurements also indicate the key role of the metal housing around the battery pack in thermal management. Measurements are found to be in good agreement with finite element simulations, which indicate that the battery pack can be cooled as effectively in presence of a perforated metal casing as without the casing at all. Experimental data and simulation model presented here offer critical insights into the design of hoverboard thermal management and may result in safer, high performance hoverboard battery packs. 相似文献
970.
The effects of sintering additives on photostriction properties have been rarely reported and the polarization effect of KNN-based ceramics on the photostriction characteristics remains uncertain. In the present work, a highly feasible approach has been adopted to obtain improved photostrictive coefficient (α = 2.4 × 10?9 m2/W) for KNN-based ceramics by adding appropriate amount (x = 0.5 wt%) of MnO2 as sintering additives into 0.97(K0.5Na0.5)NbO3-0.03(La0.51Na0.49)(Zr0.54Ni0.46)O3 (97KNN-3LNNZ) ceramics. The appropriate amount of MnO2 (x ≤ 0.5 wt%) in the ceramics does not alter the inherent multi-phase structure and results in uniform grain growth of the ceramics. The ferroelectricity and piezoelectricity can be optimized by the “softening” effect of Mn2+ and Mn3+ in KNN-based ceramics. The addition of MnO2 increases energy band gap and also optimizes the optical absorption properties in the near-infrared band. 97KNN-3LNNZ+0.5 wt% MnO2 ceramics show optimum overall performance. In addition to this, for x = 0.5 wt% sample, the power-dependent Raman spectra of ceramics measured before and after the electrical poling shows that the prior E-field poling can enhance the red shift corresponding to F2g bending vibration mode. Subsequently, there are changes in bond angle of elements induced by light in oxygen octahedron. These phenomena play active roles in getting a deep understanding of the underlying mechanisms of photostriction for ferroelectric ceramics. 相似文献