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71.
《Measurement》2015
The evaluation of functional features of manufactured workpieces is based on GO- and NO-GO-test results, which are obtained by comparing measured geometric characteristics with nominal dimensions and tolerances specified by the designer. These geometrical specifications are based on a tolerancing system, which was originally defined for the function mating capability. Against the background of upcoming lots of other new functions (like reduction of flow resistance, light absorption, reduction of friction, diffraction of light, self-cleaning or mass transmission) are to be realized with our products – particularly by micro- and nano scaled features. If the verification process will deliver the prediction of the achievable degree of functionality, the usability of a part can be assessed more accurately and in consequence quality and economics can be improved. So, a new principle for tolerancing and verifying turns out to be necessary. In this paper the fundamental deficit of the actual tolerancing and specification systems GPS and ASME Y14.5 is derived and the path for enlarging the system by preposing a functional model is shown. To verify the functional capability of the workpieces an approach based on simulations done with the parameterized mathematical–physical model of the function is suggested. Advantages of this approach will be discussed and demonstrated by examples with microstructured inking rolls, crankshafts and injection valves. 相似文献
72.
The generic model query language GMQL is designed to query collections of conceptual models created in arbitrary graph-based modelling languages. Querying conceptual models means searching for particular model subgraphs that comply with a predefined pattern query. Such a query specifies the structural and semantic properties of the model fragment to be returned. In this paper, we derive requirements for a generic model query language from the literature and formally specify the language’s syntax and semantics. We conduct an analysis of GMQL׳s theoretical and practical runtime performance concluding that it returns query results within satisfactory time. Given its generic nature, GMQL contributes to a broad range of different model analysis scenarios ranging from business process compliance management to model translation and business process weakness detection. As GMQL returns results with acceptable runtime performance, it can be used to query large collections of hundreds or thousands of conceptual models containing not only process models, but also data models or organizational charts. In this paper, we furthermore evaluate GMQL against the backdrop of existing query approaches thereby carving out its advantages and limitations as well as pointing toward future research. 相似文献
73.
Functional and conformational characterisation of walnut protein obtained through AOT reverse micelles 下载免费PDF全文
Haifang Hu Yali Sun Xiaoyan Zhao Di Liu Lidan Fu Haitao Zhu 《International Journal of Food Science & Technology》2015,50(11):2351-2359
Walnut protein was extracted from defatted walnut flour by bis (2‐ethylhexyl) sodium sulfosuccinate (AOT) reverse micellar system and alkali solution with isoelectric precipitation. The functional and conformational characteristics of two proteins were investigated and compared. Walnut protein obtained through AOT reverse micelles was found to have higher extraction yield, solubility, emulsifying activity, foam capacities, water‐ and oil‐holding capacity compared to the protein from alkali solution along with isoelectric precipitation, while the surface hydrophobicity (H0), contents of disulphide bond (SS) and sulfhydryl group (SH) were relatively lower. The differences of H0, SS and SH contents could be due to the conformational changes of walnut proteins using two extraction methods. FTIR spectra and data showed that the reverse micelles caused the decrease in α‐helix, β‐sheet, random and β‐turn of walnut protein, the increase in the side‐chain structure content, which could be responsible for the modification of functional properties. 相似文献
74.
Chengjing Mi Yanping Huang Fengtao Chen Kui Wu Weiyan Wang Yunquan Yang 《International Journal of Hydrogen Energy》2021,46(1):875-885
Methylcyclohexane is a very promising liquid organic hydrogen carrier, but its dehydrogenation mechanism on Pt-based bimetallic catalysts is not yet clear. In order to understand the catalytic dehydrogenation of methylcyclohexane on Ni–Pt(111), DFT calculations were performed and the calculation results were compared with the corresponding values on Pt(111). It is shown that because the electronegativity of Ni atoms is less than that of Pt atoms, electrons transfer from Ni atoms to Pt atoms. Compared with Pt(111), the binding energy (the absolute value of the adsorption energy) of related species on Ni–Pt(111) surface was smaller, indicating that the binding strength between these species and the surface metal atoms on Ni–Pt(111) is weaker. In the stable adsorption configurations on Ni–Pt(111), almost all the metal atoms forming chemical bonds with the adsorbates were Pt atoms, indicating that Pt was the main active component. Although the actual catalytic reaction is more complicated, this study provided some insights into one of the important aspects. 相似文献
75.
软件功能安全验证活动对提高安全关键系统的安全性具有重要作用,它贯穿于软件安全生命周期的各个阶段。通过对各阶段输出文档的审查和分析,可尽早发现软件问题,降低软件修复成本。完整的问题闭环处理流程可有效解决软件验证活动中发现的问题,给出各方均满意的处理结果。 相似文献
76.
Javier Castro-Rosas Carlos Alberto Gómez-Aldapa Edgar Arturo Chávez-Urbiola Monserrat Hernández-Bautista María Luisa Rodríguez-Marín Zaira Esmeralda Cabrera-Canales Reyna Nallely Falfán-Cortés 《International Journal of Food Science & Technology》2021,56(4):1809-1817
The objective of this study was to evaluate the influence of pH, bile salts and different storage conditions at two different temperatures (30 and 4 °C) on the viability of free and microencapsulated Lactobacillus paracasei. Microspheres encapsulating L. paracasei were obtained using an extrusion method. The efficiency was 87.6%, the diameter 70 µm and the zeta potential 7.22 ± 0.05 mV. Encapsulated L. paracasei showed higher resistance to stomach pH and bile salts compared to free cells. Microspheres were evaluated under four different storage conditions: fresh, suspended in a solution with a pH of 4, suspended in saline solution and lyophilised. The lyophilised microspheres presented the highest stability with 89.2% survival rate after six weeks of storage; however, free bacteria in saline solution (0.145 N) presented a 65.3% survival rate. Finally, a new product (a strawberry ice popsicle) with possible functional characteristics was obtained using microencapsulated L. paracasei. 相似文献
77.
While most of the knowledge bases already support the English language, there is only one knowledge base for the Persian language, known as FarsBase, which is automatically created via semi-structured web information. Unlike English knowledge bases such as Wikidata, which have tremendous community support, the population of a knowledge base like FarsBase must rely on automatically extracted knowledge. Knowledge base population can let FarsBase keep growing in size, as the system continues working. In this paper, we present a knowledge base population system for the Persian language, which extracts knowledge from unlabelled raw text, crawled from the Web. The proposed system consists of a set of state-of-the-art modules such as an entity linking module as well as information and relation extraction modules designed for FarsBase. Moreover, a canonicalization system is introduced to link extracted relations to FarsBase properties. Then, the system uses knowledge fusion techniques with minimal intervention of human experts to integrate and filter the proper knowledge instances, extracted by each module. To evaluate the performance of the presented knowledge base population system, we present the first gold dataset for benchmarking knowledge base population in the Persian language, which consisting of 22015 FarsBase triples and verified by human experts. The evaluation results demonstrate the efficiency of the proposed system. 相似文献
78.
社区和居家养老是我国当前和未来的主要养老模式,然而,与机构养老设施相比较而言,我国社区居家养老服务设施的发展明显滞后,具体表现为设施的建成基础薄弱、空间资源的配置要素模糊、规范和管控手段缺位等。在概述现状与问题的基础上,系统地探讨了我国社区层面养老服务资源的配置主体、配置对象和配置思路。针对养老服务需求和供给主体日益多元化的挑战,提出结合社区实际情况灵活配置服务模块的建议,采用总量控制和复合设置的规划手段落实配建,从而实现服务设施综合效益最大化的建设目标。 相似文献
79.
This systematic review study synthesizes research findings pertaining to the use of augmented reality (AR) in language learning. Published research from 2014 to 2019 has been explored and specific inclusion and exclusion criteria have been applied resulting in 54 relevant publications. Our findings determined: (a) devices and software employed for mastering AR; languages and contexts in which AR had been applied; theoretical perspectives adopted for guiding the use of AR; the number of participants in AR activities and benefits from using AR as an educational tool in the language classroom; (b) alignment of the affordances of Augmented Reality with the KSAVE (Knowledge, Skills, Attitudes, Values, Ethics) 21st-century skills framework; (c) future directions in AR research and practice. The main findings from this review demonstrate the popularity of mobile-based AR for supporting vocabulary (23.9%), reading (12.7%), speaking (9.9%) writing (8.5%) or generic language skills (9.9%). Our findings also uncovered areas that merit future attention in the application of AR in language learning – for instance learning theories were not often considered in the implementation of AR. The study concludes with suggestions for future research especially in the areas of instructional design and user experience. 相似文献
80.