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Air management for diesel engines is a major challenge from the control point of view because of the highly nonlinear behavior of this system. For this reason, linear control techniques are unable to provide the required performance, and nonlinear controllers are used instead. This article discusses two fundamental steps when designing a control system. Firstly, a methodology to identify Takagi–Sugeno (T–S) structures using experimental data is proposed. Secondly, the design of a fuzzy controller in PDC structure (Parallel Distributed Compensation) is presented. The parameters of this controller are obtained from a LMI (Linear Matrix Inequalities) minimization problem.  相似文献   
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The present investigation evaluated the effects of virtual reality (VR) training on the performance, perceived workload and stress response to a live training exercise in a sample of Soldiers. We also examined the relationship between the perceptions of that same VR as measured by engagement, immersion, presence, flow, perceived utility and ease of use with the performance, workload and stress reported on the live training task. To a degree, these latter relationships were moderated by task performance, as measured by binary (Go/No-Go) ratings. Participants who reported positive VR experiences also tended to experience lower stress and lower workload when performing the live version of the task. Thus, VR training regimens may be efficacious for mitigating the stress and workload associated with criterion tasks, thereby reducing the ultimate likelihood of real-world performance failure.

Practitioner Summary: VR provides opportunities for training in artificial worlds comprised of highly realistic features. Our virtual room clearing scenario facilitated the integration of Training and Readiness objectives and satisfied training doctrine obligations in a compelling engaging experience for both novice and experienced trainees.  相似文献   

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The ubiquitin-proteasome system (UPS) is an established therapeutic target for approved drugs to treat selected hematologic malignancies. While drug discovery targeting the UPS focuses on irreversibly binding epoxyketones and slowly-reversibly binding boronates, optimization of novel covalent-reversibly binding warheads remains largely unattended. We previously reported α-ketoamides to be a promising reversible lead motif, yet the cytotoxic activity required further optimization. This work focuses on the lead optimization of phenoxy-substituted α-ketoamides combining the structure-activity relationships from the primed and the non-primed site of the proteasome β5 subunit. Our optimization strategy is accompanied by molecular modeling, suggesting occupation of P1′ by a 3-phenoxy group to increase β5 inhibition and cytotoxic activity in leukemia cell lines. Key compounds were further profiled for time-dependent inhibition of cellular substrate conversion. Furthermore, the α-ketoamide lead structure 27 does not affect escape response behavior in Danio rerio embryos, in contrast to bortezomib, which suggests increased target specificity.  相似文献   
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The effect of the main gangliosides (GM1, GM3, GD3) and free sialic acid (Neu5Ac) upon the adhesion of pathogenic bacteria implicated in infant diarrhoea is assessed in vitro using the Caco-2 cell line. Concentrations of the bioactive compounds found in the bioaccessible (soluble) fraction of infant formula and human milk are employed. Bacterial adhesion behaviour included enterotoxigenic Escherichia coli (ETEC), enteropathogenic E.coli (EPEC), Listeria monocytogenes, Salmonella entericaserovartyphi, Shigella sonnei, Campylobacter jejuni and Helicobacter pylori. Three different approaches were assayed: pre-incubation of bacteria and compounds before addition to cells (competition); pre-incubation of the cells with compounds (exclusion); and pre-incubation of cells with bacteria (displacement). Furthermore, the spatial localization of the most abundant gangliosides, GM3 and GD3, in Caco-2 cells has been determined using confocal microscopy. Results show that GM3, GD3, GM1 and Neu5Ac at the assayed concentrations are able to interfere with the adhesion of several pathogenic bacteria involved in neonatal diseases-the greatest effect corresponding to Neu5Ac, followed by GD3, GM1 and GM3. Gangliosides GM3 and GD3 are located in the apical and basolateral membranes of the Caco-2 cells.  相似文献   
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In construction projects, resource availability might limit the implementation of ideal schedules. Especially, when repetitive activities are involved, traditional resource‐constrained project scheduling problem (RCPSP) models fail to allocate the resource consumption in an efficient manner. Besides, actual models only provide local optimal solutions and do not incorporate activity acceleration routines. To fulfill this gap, partially, a mathematical optimization model, the multimode RCPSP for repetitive activities in construction projects, is proposed and solved to optimality; it takes into account acceleration routines under real construction scenarios using spreadsheets. The article shows a complete computational experimentation over a real construction project, considering several scenarios of resource availabilities and continuity conditions. The model allows analyzing the resources efficiency indexes comparing them to resource consumptions, continuity of activities, and objective functions that reveal that fragmented activities do not provide better resource efficiency outcomes.  相似文献   
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Our recently proposed method to extract the bulk-charge effect parameter in MOSFETs is scrutinized by studying SOI devices, a-Si:H TFTs and short- as well as long-channel bulk MOSFETs. The method requires measuring the drain current as a function of gate voltage at two small values of drain voltage chosen in the linear region of operation.  相似文献   
9.
DeviceNet现场总线技术在化工行业的应用   总被引:1,自引:0,他引:1  
王恩娜 《低压电器》2011,(11):53-56
介绍了DeviceNet现场总线的原理、技术特点,分析了DeviceNet现场总线在化工行业汽车涂料生产过程中的具体应用,详细分析了该系统的工作特点。实践表明,DeviceNet的运用使得系统更加智能化,运行更加可靠,有效地提高了生产效益。  相似文献   
10.
BACKGROUND: The aim of this study was to assess the familial aggregation of blood pressure and body mass index levels in schoolchildren of Cuenca city, Spain. SUBJECTS AND METHODS: A cross sectional study was made including 307 both sexes schoolchildren 9-12 years old recruited in three schools of Cuenca city, and 346 of their parents. There were determined sociodemographics variables, weight, height, body mass index, SBP, DBP and fasting plasma total cholesterol, cLDL, cHDL and triglyceride concentrations. RESULTS: Parents-children correlation coefficients in blood pressure levels ranged between -0.1 and 0.2. Parents-daughters correlations were stronger than parents-sons in ponderal indexes. The relationship of ponderal indexes and blood pressure between spouses was weak, with correlation coefficients between 0.08 y 0.1. By stepwise multiple regression analysis it was found that the only variable that explained a significant percentage of blood pressure variability (both systolic and diastolic) was the weight of the schoolchildren in both sexes. Parents body mass index explained more than 32% of body mass index daughter's variability. In sons any variable explained a significant percentage of variability. CONCLUSIONS: The parents-children aggregation of blood pressure is weak. Parents-children aggregation of ponderal indexes is stronger, though there are considerable sex-differences. Spouses relationship, though positive, is weak in all variables.  相似文献   
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