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排序方式: 共有1219条查询结果,搜索用时 15 毫秒
31.
Nataraj Nandita Adam Elisabeth Hansson Bill S. Knaden Markus 《Journal of chemical ecology》2021,47(12):1042-1048
Journal of Chemical Ecology - Many pollinating insects exhibit flower constancy, i.e. they target flower species they have already experienced and fed from. While the insects might profit from... 相似文献
32.
Bit commitment schemes are at the basis of modern cryptography. Since information-theoretic security is impossible both in the classical and in the quantum regime, we examine computationally secure commitment schemes. In this paper we study worst-case complexity assumptions that imply quantum bit commitment schemes. First, we show that QSZK \({\not\subseteq}\) QMA implies a computationally hiding and statistically binding auxiliary-input quantum commitment scheme. We then extend our result to show that the much weaker assumption QIP \({\not\subseteq}\) QMA (which is weaker than PSPACE \({\not\subseteq}\) PP) implies the existence of auxiliary-input commitment schemes with quantum advice. Finally, to strengthen the plausibility of the separation QSZK \({\not\subseteq}\) QMA, we find a quantum oracle relative to which honest-verifier QSZK is not contained in QCMA, the class of languages that can be verified using a classical proof in quantum polynomial time. 相似文献
33.
Bill Moran Du Q. Huynh Xuezhi Wang Michael Edwards Andrew Harris Barbara F. La Scala 《Digital Signal Processing》2009,19(5):793-808
We describe here a method for the analysis of materials on a conveyor belt using the natural gamma spectra collected with a BGO (Bismuth Germanate) gamma ray detector. This detector collects gamma ray emissions from the Potassium (K), Uranium (U), and Thorium (Th) atoms in the materials. Based on these data, and using a Poisson model for the data generation, a statistical model is proposed and an approximate maximum likelihood (ML) technique based on the expectation-maximization (EM) algorithm is then used to estimate the amount of each of the three elements in the material. The statistical model is further refined to incorporate parameters of drift in the detector and an estimation technique for this is developed and tested against real data. The Cramér–Rao lower bounds for the estimators are calculated. 相似文献
34.
Bill Venners 《程序员》2009,(5):81-83
Twitter将部分应用从Ruby迁移到了Scala。三位开发者详谈决策背后的因素、Scala在现实应用中遇到的困难以及Scala对编程风格的影响。 相似文献
35.
Bill 《Windows IT Pro Magazine》2009,(8):41-41
Windows XP模式可用在Windows 7的Professiona Enterprise和Ultimate版本中。它实质上由两部分构成版的Virtual PC,名为Windows Virtual PC:通过Windows Firewall进行配置并能自动更新的Windows XP Professiona SP3虚拟机(VM)。如果OEM选择安装Windows XP模式,可以预先在新计算机上安装它,也可以通过微软站点下载它。 相似文献
36.
Maureen T. Ross Rena Cruz Trent L. Brooks-Richards Louise M. Hafner Sean K. Powell Maria A. Woodruff 《Virtual and Physical Prototyping》2018,13(4):255-265
Congenital facial anomalies, such as microtia (malformation of the external ear), lead to significant psychosocial effects starting from early childhood. Three-dimensional (3D) scanning and advanced manufacturing are being investigated as a cheaper and more personalised method of fabricating reconstructive treatments for patients compared to traditional approaches. To date, most case studies have used expensive 3D scanners, yet, there is potential for low-cost devices to provide comparable results. This study aimed to investigate these different approaches. Both ears of 16 adult participants were scanned with three devices: Artec Spider (Artec Group), Intel® RealSense? (Intel), and the Apple iPhone® 7 (Apple Inc.) combined with photogrammetry using 90, 60 and 30 photographs. The scanning time, processing time, accuracy, completeness, resolution and repeatability of each technique were assessed using the Artec Spider as a reference scanner. Our results show that the iPhone had the longest processing time however, this decreased nine-fold when reducing the number of photos from 90 to 30. There was no significant difference in the accuracy, completeness or repeatability of the iPhone scans with 90 photographs (1.4?±?0.6?mm, 79.9%, 1.0?±?0.1?mm), 60 photographs (1.2?±?0.2, 79.3%, 0.9?±?0.2?mm) or 30 photographs (1.2?±?0.3?mm, 74.3%, 1.0?±?0.2?mm). The Intel RealSesne performed significantly worse in each parameter (1.8?±?03?mm; 46.6%, 1.4?±?0.5). Additionally, the RealSense had significantly lower resolution with not enough detail captured for the application. These results demonstrate that the ear can be accurately 3D scanned using iPhone photographs. We would recommend capturing between 30 and 60 photographs of the ear to create a scan that is accurate but without the downfall of long processing time. Using these methods we aim to provide a more comfortable setting for the patient and a lower-cost and more personalised ear prosthesis. 相似文献
37.
Nita G Brooks Cindy K Riemenschneider Bill C Hardgrave Anne M O'Leary-Kelly 《欧洲信息系统杂志》2011,20(1):87-102
A theoretical model of professional identification is developed and empirically examined as a means to understanding information technology (IT) workers’ attachment to the IT profession. Professional identification represents oneness with or belonging to a profession and provides a unique means of investigating and evaluating the IT profession. Results from a survey of 305 IT workers indicate that professional identification is directly impacted by three factors: (1) the individual's need for professional identification; (2) the individual's perceived similarity to others in the IT profession; and (3) the individual's perceptions of the IT profession, signifying the importance of internalization to identification. Professional identification is also indirectly impacted by the public's perception of the IT profession. 相似文献
38.
Recovering 3D human pose from monocular images 总被引:8,自引:0,他引:8
39.
计算机对化学实验数据进行实时采集和处理具有效率高和可靠性好等优点 ,以往采用单片机、PLC系统的较多 ,为了改进系统的设计 ,采用自行设计的小信号调理接口板、智能数据采集模块、RS - 485网络与微机连接的硬件设计 ,以及先进的Delphi语言和面向对象的软件开发技术 ,成功地开发出一种通用、任意通道的微机数据采集监测系统。该系统通用性和扩展性好 ,可以进行多通道、远距离的数据采集。系统硬件、软件和网络结构设计灵活 ,功能强大 ,首先在 72 1型分光光度计上得以成功应用 ,并可广泛应用于多种化学实验和相关科学研究与教学中 相似文献
40.
Jeff Falin Bill Johns 《电子设计应用》2006,(2):6211x
作者:Jeff Falin、Bill Johns·电源管理产品/便携式电源DC/DC应用TPS6211x dc/dc转换器是一种同步降压转换器,其输入电压最高可达17V,输出电压范围为1.2-16V,输出电流高达1.5A。该器件可以高效地将两节锂离子电池、铅酸蓄电池或12V-15V系统电压降至5V、3.3V或者更低。图1为典型应用电路。图1:典型应用本文将提供TPS62111x降压转换器的示例应用并对关键特性进行总结,以供实际设计参考。外部组件的尺寸要求集成FET及内部补偿功能可进一步减少外部组件教。假设不使用集成输出电压与输入电压监控电路,则固定输出电压(5V或3.3V)时仅… 相似文献