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1.
Thomas R. Savage Fernando Almeida-Trasvina Ehecatl A. del-Rio Chanona Robin Smith Dondga Zhang 《American Institute of Chemical Engineers》2021,67(11):e17358
With liquefied natural gas becoming increasingly prevalent as a flexible source of energy, the design and optimization of industrial refrigeration cycles becomes even more important. In this article, we propose an integrated surrogate modeling and optimization framework to model and optimize the complex CryoMan Cascade refrigeration cycle. Dimensionality reduction techniques are used to reduce the large number of process decision variables which are subsequently supplied to an array of Gaussian processes, modeling both the process objective as well as feasibility constraints. Through iterative resampling of the rigorous model, this data-driven surrogate is continually refined and subsequently optimized. This approach was not only able to improve on the results of directly optimizing the process flow sheet but also located the set of optimal operating conditions in only 2 h as opposed to the original 3 weeks, facilitating its use in the operational optimization and enhanced process design of large-scale industrial chemical systems. 相似文献
2.
Jean-Charles Passieux Robin Bouclier 《International journal for numerical methods in engineering》2019,119(6):453-468
Today, effective implementations of digital image correlation (DIC) are based on iterative algorithms with constant linear operators. A relevant idea of the classic finite element (or, more generally, global) DIC solver consists in replacing the gradient of the deformed state image with that of the reference image, so as to obtain a constant operator. Different arguments (small strains, small deformations, equality of the two gradients close to the solution, etc) have been given in the literature to justify this approximation, but none of them are fully accurate. Indeed, the convergence of the optimization algorithm has to be investigated from its ability to produce descent directions. Through such a study, this paper attempts to explain why this approximation works and what is its domain of validity. Then, an inverse compositional Gauss-Newton implementation of finite element DIC is proposed as a cost-effective and mathematically sound alternative to this approximation. 相似文献
3.
Daniel Whittaker Andreas Geist Giuseppe Modolo Robin Taylor Mark Sarsfield Andreas Wilden 《溶剂提取与离子交换》2018,36(3):223-256
Over the last decade there has been much interest in the applications of diglycolamide (DGA) ligands for the extraction of the trivalent lanthanide and actinide ions from PUREX high active raffinates or dissolved spent nuclear fuel. Of the DGAs, the N,N,N’,N’-tetraoctyldiglycolamide (TODGA) is the best known and most widely studied. A number of new actinide separation processes have been proposed based on extraction with TODGA. This review covers TODGA-based processes and extraction data, specifically focusing on how phase modifiers have been used to increase metal loading and thus enhance the operating process envelopes. Effects of third phase formation and the organic phase speciation are reviewed in this context. Relevant aspects of the extraction chemistry of important solvents (TODGA-modifier-diluent combinations) are described and their performances demonstrated by a consideration of the published flowsheet tests. It is seen that modifiers are successfully enabling the use of TODGA in actinide separation processes but to date the identification and testing of suitable modifiers has been rather empirical. There is a growing understanding of the fundamental chemistry occurring in the organic phase and how that affects extractant speciation and metal loading capacity but studies are still needed if TODGA-based flowsheets are to become an industrially deployable option for minor actinide (MA) recovery processes. 相似文献
4.
WENXI GAO QIANQIAN MA CHENYU TANG YUELI ZHAN YINONG DUAN HUIHUA NI YUNZHAO XU 《Biocell》2020,44(4):597-605
Cervical cancer (CESC) is one of the most common cancers and affects the female genital tract. Consistent HPV
infection status has been determined to be a vital cause of tumorigenesis. HPV infection may induce changes to the
immune system and limit the host’s immune response. Immunotherapy is therefore essential to improving the overall
survival of both locally advanced and recurrent CESC patients. Using 304 relevant samples from TCGA, we assessed
immune cell function in CESC patients to better understand the status of both tumor micro-environment cells and
immune cells in CESC. Functional enrichment analysis, pathway enrichment analysis, and PPI network construction
were performed to explore the differentially expressed genes (DEGs). The analysis identified 425 DEGs, which
included 295 up-regulated genes and 130 down-regulated genes. We established that upregulation of CCL5 was
correlated with significantly better survival, meaning that CCL5 expression could serve as a novel prognostic
biomarker for CESC patients. We further focused on CCL5 as a hub gene in CESC, as it had significant correlations
with increased numbers of several types of immune cells. Cell-type fractions of M1 macrophages were significantly
higher in the high-immune-scores group, which was associated with better overall survival. Finally, we concluded that
CCL5 is a promising prognostic biomarker for CESC, as well as a novel chemotherapeutic target. 相似文献
5.
基于UC/OS—Ⅱ实时操作系统的网络控制系统,通过以太网将服务器和各地控制器联结,可控制多个电机协调运动.服务器采用工业级计算机,客户端(控制器)采用集成网卡接口的嵌入式系统,通过交换机进行数据交换.系统根据IP地址将命令送给各控制器,同时将客户端状态返回,并通过检验校验字符的方式减少联网过程的握手次数.其通讯的最基本函数用标准C语言编写,生成静态库文件,可直接通过工程方式使用.其通讯接口包括联网初始化、服务器和客户端网络联接、以及控制、并常处理和维护等程序。 相似文献
6.
热镀锌板(卷)工程设计中的环境保护问题 总被引:1,自引:0,他引:1
对热镀锌板(卷)的生产工艺、主要生产设备进行了简要介绍,并就其污染源(工序)、生产过程中产生的污染物及其控制措施进行了评述,同时就设计和生产中宜注意的几个环保问题进行了分析。 相似文献
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Thirty patients who had undergone either a right or left unilateral temporal lobectomy (14 RTL; 16 LTL) and 16 control participants were tested on a computerized human analogue of the Morris Water Maze. The procedure was designed to compare allocentric and egocentric spatial memory. In the allocentric condition, participants searched for a target location on the screen, guided by object cues. Between trials, participants had to walk around the screen, which disrupted egocentric memory representation. In the egocentric condition, participants remained in the same position, but the object cues were shifted between searches to prevent them from using allocentric memory. Only the RTL group was impaired on the allocentric condition, and neither the LTL nor RTL group was impaired on additional tests of spatial working memory or spatial manipulation. The results support the notion that the right anterior temporal lobe stores long-term allocentric spatial memories. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.
The present empirical investigation had a 3-fold purpose: (a) to cross-validate L. R. Offermann, J. K. Kennedy, and P. W. Wirtz's (1994) scale of Implicit Leadership Theories (ILTs) in several organizational settings and to further provide a shorter scale of ILTs in organizations; (b) to assess the generalizability of ILTs across different employee groups, and (c) to evaluate ILTs' change over time. Two independent samples were used for the scale validation (N1 = 500 and N2 = 439). A 6-factor structure (Sensitivity, Intelligence, Dedication, Dynamism, Tyranny, and Masculinity) was found to most accurately represent ELTs in organizational settings. Regarding the generalizability of ILTs, although the 6-factor structure was consistent across different employee groups, there was only partial support for total factorial invariance. Finally, evaluation of gamma, beta, and alpha change provided support for ILTs' stability over time. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献