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排序方式: 共有2393条查询结果,搜索用时 15 毫秒
31.
Peter Chemweno Liliane Pintelon Anne‐Marie De Meyer Peter N. Muchiri Adriaan Van Horenbeek James Wakiru 《Quality and Reliability Engineering International》2017,33(3):551-564
The failure mode and effect analysis (FMEA) is a widely applied technique for prioritizing equipment failures in the maintenance decision‐making domain. Recent improvements on the FMEA have largely focussed on addressing the shortcomings of the conventional FMEA of which the risk priority number is incorporated as a measure for prioritizing failure modes. In this regard, considerable research effort has been directed towards addressing uncertainties associated with the risk priority number metrics, that is occurrence, severity and detection. Despite these improvements, assigning these metrics remains largely subjective and mostly relies on expert elicitations, more so in instances where empirical data are sparse. Moreover, the FMEA results remain static and are seldom updated with the availability of new failure information. In this paper, a dynamic risk assessment methodology is proposed and based on the hierarchical Bayes theory. In the methodology, posterior distribution functions are derived for risk metrics associated with equipment failure of which the posterior function combines both prior functions elicited from experts and observed evidences based on empirical data. Thereafter, the posterior functions are incorporated as input to a Monte Carlo simulation model from which the expected cost of failure is generated and failure modes prioritized on this basis. A decision scheme for selecting appropriate maintenance strategy is proposed, and its applicability is demonstrated in the case study of thermal power plant equipment failures. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
32.
Wenbo Zhou Julia Craft Alex Ojemann Luke Bergen Arin Graner Aitana Gonzales Qianbin He Timothy Kopper Marie Smith Michael W. Graner Xiaoli Yu 《International journal of molecular sciences》2022,23(13)
WHO Grade 4 IDH-wild type astrocytoma (GBM) is the deadliest brain tumor with a poor prognosis. Meningioma (MMA) is a more common “benign” central nervous system tumor but with significant recurrence rates. There is an urgent need for brain tumor biomarkers for early diagnosis and effective treatment options. Extracellular vesicles (EVs) are tiny membrane-enclosed vesicles that play essential functions in cell-to-cell communications among tumor cells. We aimed to identify epitopes of brain tumor EVs by phage peptide libraries. EVs from GBM plasma, MMA plasma, or brain tumor cell lines were used to screen phage-displayed random peptide libraries to identify high-affinity peptides. We purified EVs from three GBM plasma pools (23 patients), one MMA pool (10 patients), and four brain tumor cell lines. We identified a total of 21 high-affinity phage peptides (12 unique) specific to brain tumor EVs. The peptides shared high sequence homologies among those selected by the same EVs. Dose–response ELISA demonstrated that phage peptides were specific to brain tumor EVs compared to controls. Peptide affinity purification identified unique brain tumor EV subpopulations. Significantly, GBM EV peptides inhibit brain tumor EV-induced complement-dependent cytotoxicity (necrosis) in neurons. We conclude that phage display technology could identify specific peptides to isolate and characterize tumor EVs. 相似文献
33.
Within the field of Information Systems, a good proportion of research is concerned with the work organisation and this has,
to some extent, restricted the kind of application areas given consideration. Yet, it is clear that information and communication
technology deployments beyond the work organisation are acquiring increased importance in our lives. With this in mind, we
offer a field study of the appropriation of an online play space known as Habbo Hotel. Habbo Hotel, as a site of media convergence,
incorporates social networking and digital gaming functionality. Our research highlights the ethical problems such a dual
classification of technology may bring. We focus upon a particular set of activities undertaken within and facilitated by
the space—scamming. Scammers dupe members with respect to their ‘Furni’, virtual objects that have online and offline economic
value. Through our analysis we show that sometimes, online activities are bracketed off from those defined as offline and
that this can be related to how the technology is classified by members—as a social networking site and/or a digital game.
In turn, this may affect members’ beliefs about rights and wrongs. We conclude that given increasing media convergence, the
way forward is to continue the project of educating people regarding the difficulties of determining rights and wrongs, and
how rights and wrongs may be acted out with respect to new technologies of play online and offline.
Marie Griffiths moved from the IT industry into academia and is now based at the University of Salford as an EPSRC Academic Fellow. She has, and continues to research gender and ICTs. Recently she has embarked upon the study “Cybercitizens and their Virtual Pursuits” to understand the consequence of growing up and living in a technologically saturated environment. Her work has been published in journals such as Gender, Work and Organization, the European Journal of Information Systems and Information Communication and Society. Ben Light is Professor of Technology and Society at the University of Salford. His research concerns the appropriation of configurable technologies within work, organisations and society. This has led him to explore the use of large-scale enterprise resource planning packages, call centre technologies, social networking sites and digital games. He has published in journals such as Communications of the ACM, Information Systems Journal, New Technology, Work and Employment, the European Journal of Information Systems and the Journal of Information Technology. 相似文献
Ben LightEmail: |
Marie Griffiths moved from the IT industry into academia and is now based at the University of Salford as an EPSRC Academic Fellow. She has, and continues to research gender and ICTs. Recently she has embarked upon the study “Cybercitizens and their Virtual Pursuits” to understand the consequence of growing up and living in a technologically saturated environment. Her work has been published in journals such as Gender, Work and Organization, the European Journal of Information Systems and Information Communication and Society. Ben Light is Professor of Technology and Society at the University of Salford. His research concerns the appropriation of configurable technologies within work, organisations and society. This has led him to explore the use of large-scale enterprise resource planning packages, call centre technologies, social networking sites and digital games. He has published in journals such as Communications of the ACM, Information Systems Journal, New Technology, Work and Employment, the European Journal of Information Systems and the Journal of Information Technology. 相似文献
34.
Hierarchial Zeolites: Beyond Creation of Mesoporosity: The Advantages of Polymer‐Based Dual‐Function Templates for Fabricating Hierarchical Zeolites (Adv. Funct. Mater. 12/2016) 下载免费PDF全文
35.
Clara Savary Ccile Picard Nadge Corradini Marie Castets 《International journal of molecular sciences》2022,23(11)
Soft tissue sarcoma (STS) comprise a large group of mesenchymal malignant tumors with heterogeneous cellular morphology, proliferative index, genetic lesions and, more importantly, clinical features. Full elucidation of this wide diversity remains a central question to improve their therapeutic management and the identity of cell(s)-of-origin from which these tumors arise is part of this enigma. Cellular reprogramming allows transitions of a mature cell between phenotypes, or identities, and represents one key driver of tumoral heterogeneity. Here, we discuss how cellular reprogramming mediated by driver genes in STS can profoundly reshape the molecular and morphological features of a transformed cell and lead to erroneous interpretation of its cell-of-origin. This review questions the fact that the epigenetic context in which a genetic alteration arises has to be taken into account as a key determinant of STS tumor initiation and progression. Retracing the cancer-initiating cell and its clonal evolution, notably via epigenetic approach, appears as a key lever for understanding the origin of these tumors and improving their clinical management. 相似文献
36.
Once merely thought of as the protein responsible for the overall physical nature of the human immunodeficiency virus type 1 (HIV-1), the Gag polyprotein has since been elucidated to have several roles in viral replication and functionality. Over the years, extensive research into the polyproteins’ structure has revealed that Gag can mediate its own trafficking to the plasma membrane, it can interact with several host factors and can even aid in viral genome packaging. Not surprisingly, Gag has also been associated with HIV-1 drug resistance and even treatment failure. Therefore, this review provides an extensive overview of the structural and functional roles of the HIV-1 Gag domains in virion integrity, functionality and infectivity. 相似文献
37.
Ravichandran Ramasamy Alexander Shekhtman Ann Marie Schmidt 《International journal of molecular sciences》2022,23(9)
Increasing evidence links the RAGE (receptor for advanced glycation end products)/DIAPH1 (Diaphanous 1) signaling axis to the pathogenesis of diabetic complications. RAGE is a multi-ligand receptor and through these ligand–receptor interactions, extensive maladaptive effects are exerted on cell types and tissues targeted for dysfunction in hyperglycemia observed in both type 1 and type 2 diabetes. Recent evidence indicates that RAGE ligands, acting as damage-associated molecular patterns molecules, or DAMPs, through RAGE may impact interferon signaling pathways, specifically through upregulation of IRF7 (interferon regulatory factor 7), thereby heralding and evoking pro-inflammatory effects on vulnerable tissues. Although successful targeting of RAGE in the clinical milieu has, to date, not been met with success, recent approaches to target RAGE intracellular signaling may hold promise to fill this critical gap. This review focuses on recent examples of highlights and updates to the pathobiology of RAGE and DIAPH1 in diabetic complications. 相似文献
38.
Mohamed Ben Bettaieb Xavier LemoineOlivier Bouaziz Anne Marie HabrakenLaurent Duchêne 《Mechanics of materials : an international journal》2011,43(3):139-156
In order to couple the damage evolution and the stress state of DP steel grades, a new advanced GTN (Gurson-Tvergaard-Needleman) model was developed and implemented into a finite element code. This model is an extension of the original one. It takes into account the plastic anisotropy and the mixed (isotropic + kinematic) hardening of the matrix. Two different methods to compute the void volume fraction were developed and used within the constitutive equations. The first method is new and allows the accurate modeling of the observations of damage initiation and growth in DP steels measured using high-resolution X-ray absorption tomography ( [Bouaziz et al., 2008] and [Maire et al., 2008]). The second method is classic and assumes the additive decomposition of the total void volume fraction into a nucleation and a growth part. A parametric study is carried out to assess the effect of the kinematic hardening on some mechanical parameters such as the equivalent plastic strain, the triaxiality and the porosity. The numerical predictions are favorably compared to the experimental results. 相似文献
39.
Marie Kubešová Jan Ku?era 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,654(1):206-212
For many years the well-established Kayzero for Windows software for neutron activation analysis (NAA) using k0 standardization was the only commercial program available. Recently, the freeware k0-IAEA software has been launched by the International Atomic Energy Agency (IAEA). The software is based on an adapted Høgdahl convention in which the cadmium cut-off energy from the k0-formulas is removed. The holistic approach of γ-ray spectra evaluation is used which minimizes the user's interaction with the software.Several certified reference materials were analyzed with the k0-IAEA and Kayzero for Windows software using the same gamma-ray spectra obtained from several irradiation and counting modes. The results obtained were compared and evaluated in terms of precision, accuracy and detection limits. The work-flow procedures performed by the two software packages and the results obtained are discussed. 相似文献
40.
Aspects of reconfigurable and flexible fixtures 总被引:1,自引:0,他引:1
The design and manufacture of fixtures and other dedicated tooling for positioning of workpieces are among the major cost drivers in product industrialization. This has spurred research and commercial interest towards other fixturing solutions like reconfigurable fixtures, with the ability to be changed, or “reconfigured”, to suit different parts and products. When reconfiguring, the product interface not only has to be moved but moved to a desired position and orientation. Several different approaches have been used to move and position these devices, all with their own advantages and disadvantages. This article presents different methods used to position and reconfigure flexible fixture devices using a parallel kinematic device as a case. Discussing the different ways to reconfigure a flexible device, the article aims to arrange the techniques according to their key features. 相似文献