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61.
在电子皮带秤称量输送物料的传输系统中,当出现对实物标定困难和安装位置不便于链码标定的计量点时,简单、易行的选择就是进行挂码标定。笔者就怎样减少挂码标定的误差,获得较高的标定精确度等,进行了探讨,可供相关专业参考。 相似文献
62.
采用棒基组合的装配方法,用热挤压和冷加工相结合的工艺制备了岛状Ti5Nb人工钉扎中心NbTi超导体,其中Ti5Nb体积含量为10%。通过对此超导体进行详细的磁通钉扎机制分析,认为样品的磁通钉扎力特征主要由正常相钉扎和Δκ扎相结合的机制决定。根据分析的结果,采用多源标度方法,很好地拟合了不同线径样品的磁通钉扎力密度随磁场变化的曲线。拟合的结果表明:样品在较低场下的性能主要由正常相钉扎机制决定,而在较高场下的性能主要由Δκ钉扎机制决定。并且随着线径的减小,正常相钉扎力密度和Δκ钉扎力密度均有不同程度的提高。 相似文献
63.
随着电子科学技术的发展,用作电子材料的陶瓷的研究和开发十分引人注目,许多工厂和科研人员正在研究开发电子陶瓷新材料、新工艺和新器件,以满足电子科学技术的发展对高性能陶瓷材料的要求。本文简要介绍了电子陶瓷系统中绝缘体、介电质、压电体及铁电薄膜材料及其制备工艺和应用方面的一些新进展。 相似文献
64.
Andrew J. Morris Rebecca J. Nicholls Chris J. Pickard Jonathan R. Yates 《Computer Physics Communications》2014
We present OptaDOS, a program for calculating core-electron and low-loss electron energy loss spectra (EELS) and optical spectra along with total-, projected- and joint-density of electronic states (DOS) from single-particle eigenenergies and dipole transition coefficients. Energy-loss spectroscopy is an important tool for probing bonding within a material. Interpreting these spectra can be aided by first principles calculations. The spectra are generated from the eigenenergies through integration over the Brillouin zone. An important feature of this code is that this integration is performed using a choice of adaptive or linear extrapolation broadening methods which we show produces higher accuracy spectra than standard fixed-width Gaussian broadening. OptaDOS may be straightforwardly interfaced to any electronic structure code. OptaDOS is freely available under the GNU General Public licence from http://www.optados.org. 相似文献
65.
Kerstin A. Kessel Christian Bohn Uwe Engelmann Dieter Oetzel Nina Bougatf Rolf Bendl Jürgen Debus Stephanie E. Combs 《Computer methods and programs in biomedicine》2014
In radiation oncology, where treatment concepts are elaborated in interdisciplinary collaborations, handling distributed, large heterogeneous amounts of data efficiently is very important, yet challenging, for an optimal treatment of the patient as well as for research itself. This becomes a strong focus, as we step into the era of modern personalized medicine, relying on various quantitative data information, thus involving the active contribution of multiple medical specialties. Hence, combining patient data from all involved information systems is inevitable for analyses. Therefore, we introduced a documentation and data management system integrated in the clinical environment for electronic data capture. We discuss our concept and five-year experience of a precise electronic documentation system, with special focus on the challenges we encountered. We specify how such a system can be designed and implemented to plan, tailor and conduct (multicenter) clinical trials, ultimately reaching the best clinical performance, and enhancing interdisciplinary and clinical research. 相似文献
66.
印元军 《电脑与微电子技术》2014,(18):35-37
计算机实践教学是高职教育的重要环节,传统的多媒体教学手段已经无法满足现代计算机实践教学的需求。电子教室是现代信息技术的产物,也是现代计算机实践教学过程中重要的工具,倡导电子教室与传统教学手段相结合,既能提升学生获取知识的便捷性,又能激发学生的学习兴趣。 相似文献
67.
才让卓玛 《自动化与仪器仪表》2014,(6):140-143
国内从20世纪60年代中期开始模拟指针式电子秤的研制和生产,经历了模拟式电子秤、数字式电子秤和微机式电子秤三个阶段,功能上包括各种参数的设定、自动处理及毛重、净重、皮重和累加值的显示等。为了管理和参数设置的方便,还配有与上位计算机的串行通信接口。面向定量包装称量控制领域,借鉴国内外可编程称重控制器的设计,给出了可编程称重控制器的主要设计方案和技术指标,开发了一款基于C8051F020增强型单片机的可编程称重控制器,详细给出了称重控制器的设计方法,根据配料生产的工艺要求,采用单片微机设计,集测量控制一体化的新型称重控制器,可实现自动称重、配料控制和联机测控,具有较高的性能价格比,并具备了完善的可编程功能,是一款集称重控制、可编程控制、称重变送于一体,可准确方便的实现各种复杂控制的多功能称重控制器。设计的配料控制器具有可靠性高、抗干扰能力强、性价比高和体积小巧、功能全面等特点,它既可以作为单机仪表使用,也可以作为嵌入式仪表通过RS-232或RS-485标准接口与上位工控机组网联用。 相似文献
68.
Water-soluble amino acid derivatives of gadolinium (Gd) endohedral metallofullerenes (AAD-EMFs), Gd@C82Om(OH)n(NHCH2CH2COOH)l (m ≈ 6, n ≈ 16 and l ≈ 8) are synthesized by a direct reaction of the pure endohedral metallofullerene Gd@C82 with an excess of alkaline solution of β-alanine. The structure of the AAD-EMFs is characterized by FTIR, XPS and laser-desorption time-of-flight (LD-TOF) mass spectrometries. Water proton relaxivity analysis indicates that the longitudinal relaxivity R1 (the effect on 1/T1, 9.1 mM−1 s−1) of AAD-EMFs is higher than that of the commercial MRI contrast agent, Magnevist (gadolinium-diethylenetriaminepentaacetic acid, Gd-DTPA, 5.6 mM−1 s−1). The MRI phantom studies are performed to confirm the high efficiency of this sample as MRI contrast agents. 相似文献
69.
Single-walled carbon nanotube networks grown on SiO2 pillars were studied by means of scanning photoemission microscopy. The individual nanotubes or nanotube bundles growing from the pillar tops were observed in C 1s images. Band bending near catalytic Fe/nanotube contacts in an end-bonded configuration was studied by measuring C 1s spectra along the tube axes. Within our experimental resolution, no band bending was observed. This implies that the depletion width is less than the spatial resolution of the scanning photoemission microscope (90 nm) or that the amount of the band bending is less than 0.1 eV. 相似文献
70.
《Electronic Commerce Research and Applications》2014,13(6):431-439
Many social network websites have been aggressively exploring innovative electronic word-of-mouth (eWOM) advertising strategies using information shared by users, such as posts and product reviews. For example, Facebook offers a service allowing marketers to utilize users’ posts to automatically generate advertisements. The effectiveness of this practice depends on the ability to accurately predict a post’s influence on its readers. For an advertising strategy of this nature, the influence of a post is determined jointly by the features of the post, such as contents and time of creation, and the features of the author of the post. We propose two models for predicting the influence of a post using both sources of influence, post- and author-related features, as predictors. An empirical evaluation shows that the proposed predictive features improve prediction accuracy, and the models are effective in predicting the influence score. 相似文献