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51.
介绍了一种望远数码相机的同步调焦机构的工作原理、可靠性分析、结构设计及调校工艺要求,该同步调焦机构使望远物镜和数码照相物镜在3m~∞范围内实现同步望远拍摄功能。试制结果证明:该机构使望远镜真正成为了数码相机的光学取景器,实现了产品的"所拍即所看"的同步望远拍摄功能。 相似文献
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为提高针尖增强拉曼系统对焦准确性和效率,提出通过分析CCD相机拍摄的光斑图像的像素值实现自动对焦的方法。首先快速粗调焦缩小调焦范围,然后再慢速细调焦提高调焦精度。实验表明:与Tenengrad评价函数相比,方差评价函数更适用于针尖增强拉曼光谱测量系统自动对焦,聚焦到样品表面时对焦结果的无偏估计标准差<0.25μm,具有较高的重复性和鲁棒性;快速粗调焦可提高调焦效率,避免陷入局部最优解;慢速细调焦评价函数曲线在焦点附近呈现“M”形,可通过二次拟合提高调焦精度。 相似文献
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《Measurement》2016
Employing multiple sensors that generate different physical parameters from the measured system to monitor its health increases the diagnosis reliability. In the present work, bearing diagnosis capabilities of proximity probes are explored by exploiting its advantages and alleviating its shortcomings using appropriate signal processing of the raw time domain data. A Time Synchronous Averaging based method is proposed for processing of the data acquired by proximity probes and its benefit is illustrated on test bearings. Simultaneous synchronous data is acquired with the help of proximity probes and accelerometer during a life test as the defect is naturally induced and progressed with time. The proximity probe is shown to perform better diagnosis for inner race defect compared to accelerometer due to a direct transmission path for this defect. The use of proximity probe can effectively supplement the information from accelerometer and improve the accuracy of bearing diagnosis. 相似文献
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Panayiota Tsatsou 《Behaviour & Information Technology》2020,39(9):995-1010
ABSTRACT This paper presents an in-depth study of intra-disability diversity in the digital realm and the related role of individuality and selectiveness in the digital choices and experiences of people with disabilities (PwD). The study adopts the interactionist model of disability and problematises conceptual uniformity in research that focuses on the medical and socially-constructed features of disability as those determining digital constraints and affordances for PwD. Through primary qualitative evidence, it argues that individuality and selectiveness shape a complex terrain of intra-disability diversity, which forms the nuances and experiences of digital inclusion for PwD. Thus, it invites researchers to move beyond disability-fixed categorisations and offers a 3-tier recommendation for future research to explain the range of PwD’ perceptions and experiences in the digital realm. 相似文献
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To ensure safety in nuclear power plants, this study investigated the interface design of a digital alarm system by analyzing the diagnosing process of operating information. This study focused on the layout planning of alarm windows and followed proximity compatibility principle and nuclear human–system interface design review guidelines to improve the human–system interface. This study adopt systematic layout planning to modify the design of alarm windows. The time of alarm handling, and accuracy, as well as human reliability were evaluated to compare the original layout with the improved one. In the end, according to the results of the comparison, an alternative alarm window layout human–system interface, which fits diagnosing process, is suggested.Relevance to industryThe similar layout planning process could be applied to design control centers in high reliability organizations, in particular which need decision-making by person. 相似文献
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Laura Vázquez‐Araújo Edgar Chambers IV Panat Cherdchu 《Journal of food science》2012,77(10):S384-S389
Abstract: Because sorghum grain has important characteristics (for example, great antioxidant profile) for introduction into the regular human diet, producers and industry aim to develop successful products using sorghum as the base. The 1st step in developing products attractive for consumers is understanding consumer needs and expectations. Conjoint analysis determines attributes which may be important or unimportant for one product. In this study, focus groups and conjoint analysis were used to establish which attributes are helpful for promoting purchase intent of sorghum grain products. Once those characteristics were chosen, a national survey was conducted to confirm the selection. During the focus groups, the heath aspects of grain products seemed to be the most appealing for consumers, whereas conjoint analysis showed that sensory attributes were the principal drivers for purchase intent. Practical Application: The data presented in this study are essential for industry as a starting point for developing sorghum grain based food products. It is necessary to address consumers’ demands to ensure new products’ success in the market, and the present study clearly shows this consumers’ input. 相似文献
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S. V. Gol’din L. A. Nazarov L. A. Nazarova M. P. Kozlova 《Journal of Mining Science》2007,43(3):237-246
Dilatancy zones generated by an active internal source of isolated force in a heterogeneous rock mass are studied. Based on
the solution of an inverse problem, the method is proposed for locating and determining the source focus parameters using
the measurement data on strains of the daylight surface.
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Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 3, pp. 25–35, May–June, 2007. 相似文献