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1.
The human‐machine interface design is not a new problem; however, existing knowledge appears to be focused either on interface conceptual design, which determines what information at what time needs to be displayed, or on interface detailed design, which determines the form of display elements. This article presents a study on interface layout design. Three interface layout designs were proposed based on the proximity compatibility priniciple, which were on the same interface conceptual design. In particular, the first interface layout design is with the highest degree of proximity cognition and the second and third with a reduced degree of proximity cognition. They are called sophisticated, semisophisticated, and nonsophisticated interfaces, respectively. An experiment with a simple process plant was conducted to understand user behaviors on the three interfaces. It is noted that in order to provide an unbiased comparative evaluation of these interfaces the same application problem and similar look‐and‐feel forms of interfaces were designed. In the experiment, three general classes of tasks were considered, namely, normal control operation, fault detection (or monitoring), and fault diagnosis. Two categories of measures were used: the performance measure and the subjective measure. The major results obtained from the experiment are 1) the nonsophisticated interface is the best for fault detections in terms of performance measure; besides, this interface has the lowest mental workload for fault detection; 2) the sophisticated interface is the best for normal operation in terms of performance measure; 3) there appears no significant difference for fault diagnosis in terms of performance measures for all these three interfaces; 4) for normal operation and fault diagnosis, the mental workloads for the three interfaces have no significant difference. Overall, the experiment suggests that the nonsophisticated interface be used in practice with additional two reasons: 1) most of time in the chemical process plant today is the fault detection or operation monitoring task, and 2) it is relatively easier for the nonsophisticated interface to adapt to changes in the chemical process plant design, which are common in today's manufacturing environments.  相似文献   
2.
各向异性的分形地形生成方法研究   总被引:1,自引:0,他引:1       下载免费PDF全文
传统的分形地形生成方法得到的地形是各向同性的,为了使生成的分形地形具有各向异性特征,提出了一种新的分形地形生成方法,该方法利用组合分形布朗曲面模型,将具有不同特征的两种分形布朗曲面相融合,使得生成的地形具有各向异性特征.对组合分形布朗曲面算法进行了仿真实验,生成了最终的分形地形.对仿真结果的分析表明,生成的分彤地形的特征具有各向异性特征,和实际的自然地形特征相符合,从而证明了该算法的有效性.  相似文献   
3.
Offshore operational conditions for wind farms differ from onshore especially because of their exposure to extreme weather, their remote locations and their inaccessibility in certain periods of the year. This brings a new challenge for the wind energy industry, which faces the need of more reliable systems. A common approach to improve reliability is to use component redundancies. Although this may be a good solution in some cases, it can also give undesirable consequences such as additional weight, need of additional space and cost increase. Another approach is to look at the functional capabilities of existing components to accomplish functions not initially intended to do so. In the event of a fault, these additional capabilities may be used to substitute the function of a faulty component and to have the system available for operation. This paper presents a new design philosophy based on functional redundancies and reconfiguration that can help to increase availability of wind turbines. It has a special impact on offshore applications where, in addition to the difficult accessibility, energy output per unit is more significant because of the continuous increase in sizes. An example is presented using a conceptual design of a wind turbine, showing how to find potential functional redundancies that can provide fault‐tolerant solutions and bring flexibility to the system's operation, at no significant additional weight and cost. The methodology is implemented in a software tool named Knowledge Intensive Engineering Framework, which supports functional representation and, more specifically, function‐behavior‐state modeling. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
4.
氟两相体系与甲苯硝化反应   总被引:1,自引:1,他引:0  
研究了氟溶剂和有机溶剂组成的氟两相体系、等当量的甲苯和硝酸的硝化反应.考察了硝化体系、反应时间和温度、氟溶剂的用量对硝基甲苯收率和产物异构体比例(Rp-/o-)的影响.全氟己烯(PFH)和全氟壬烯(PFN)可以和乙醚、正庚烷、四氯化碳和甲苯等有机溶剂形成氟两相体系,其互溶温度与组成有关.甲苯在全氟己烯中硝化的较佳工艺条件:n甲苯n硝酸n硫酸nPFH=110.22.0,50℃反应4h收率93.8%,Rp-/o-为0.66.冷却反应物料氟溶剂自动分层,分离简便,可循环使用.  相似文献   
5.
dl-2-hydroxy-(4-methylthio)butanoic acid (HMTBA) is a source of dietary methionine (Met) that is widely used in poultry nutrition. We have previously shown that HMTBA is preferentially diverted to the transsulfuration pathway, which gives antioxidant metabolites such as taurine and glutathione. Therefore, here we hypothesize that this Met source can protect epithelial barrier function in an in vitro model of intestinal inflammation of Caco-2 cells. The results show that HMTBA prevents the increase in paracellular permeability induced by H2O2 or tumour necrosis factor-α. This effect can be attributed to the increased production of taurine and reduced glutathione. Similar results were obtained for dl-Met, although the protective role of the amino acid was less pronounced than that of the hydroxy analogue. In conclusion, the diversion to the transsulfuration pathway means that this Met precursor is of greater value than previously thought, due to its capacity to improve intestinal homeostasis and the quality of poultry products destined for human consumption.  相似文献   
6.
分析描述性设计和情景设计的两种方法。未预见发现(Unexpected discovery,UXD)是一种驱动产品创新的科学认知设计过程。在情景类比设计过程中,通过寻找UXD来实现产品创新设计。建立功能—行为—结构(Function-behaviour-structure,FBS)模型和UXD分析模块,将情景设计与所建立的设计模块有机地结合在一起,实现产品的创新。介绍情景设计与非情景设计对FBS和UXD的影响。水龙头与房门的情景类比实例,验证了情景设计用于产品创新是行之有效的。  相似文献   
7.
Grape seed extracts (GSEs) were investigated in yeast cells harbouring defects in their antioxidant system (regarding the cellular growth and growth recovery from H2O2 insult). GSEs antioxidant activity was detected in wild-type and mutant strains Δcta1, Δgsh1 and Δoye2glr1, while pro-oxidant activity in Δsod1 cells was seen. Assessment of proliferation of prostate cancer PC3 and HBV-replicating HepG2 2.2.15 cells treated with GSEs has shown higher cytotoxicity of red grape seed extract (RW) than white grape seed extract (WW) subjective to dose and period of administration. No antiviral effect was detected by measuring the secreted virion particles in HepG2 2.2.15 cells treated with GSEs. The GSEs play a dual antioxidant/pro-oxidant role in vivo according with the cellular antioxidant system deficiencies and exhibit cytotoxic properties in PC3 and HepG2 2.2.15 cell lines, but no antiviral action against HBV.  相似文献   
8.
基于FBS模型的功能视图重组是整个企业经营过程重组的核心,由此能够导出信息、资源和组织视图的重组。基于FBS模型经营过程重组策略充分利用了企业的静态功能部分,使得重组工作只集中在过程规则集的重组上,通过过程规则集的重组来反映企业经营过程重组后的行为。这种策略减少了经营过程重组的周期和工作量。  相似文献   
9.
The effects of fucose-containing sulfated polysaccharides, ascophyllan and fucoidan, isolated from the brown alga Ascophyllum nodosum, on the growth of various cell lines (MDCK, Vero, PtK1, CHO, HeLa, and XC) were investigated. In a colony formation assay, ascophyllan and fucoidan showed potent cytotoxic effects on Vero and XC cells, while other cell lines were relatively resistant to these polysaccharides. Almost no significant effects of these polysaccharides were observed in the cell lines tested using the Alamar blue cytotoxicity assay over 48 h with varying initial cell densities (2500–20,000 cells/well) in growth medium. Interestingly, a significant growth promoting effect of ascophyllan on MDCK cells was observed, whereas treatment with fucoidan showed growth suppressive effects on this cell line under the same experimental conditions. These results suggest that ascophyllan is distinguishable from fucoidan in terms of their bioactivities. This is the first report of the growth promoting effects of a sulfated fucan on a mammalian cell line under normal growth conditions.  相似文献   
10.
The oxygen radical absorbance capacity (ORAC), antiproliferative activities and mycosporine-like amino acid (MAA) profiles of methanol extracts from two grades of dulse harvested from locations varying in UV-exposure (west vs east coasts of Grand Manan Island, NB) were determined in the present study. MAAs confirmed by LC/MS in both grades 1 (low-UV) and 2 (high-UV) dulse were palythine, shinorine, asterina-330, palythinol and porphyra-334; usujirene was present only in grade 2 dulse. ORAC values of grade 1 and 2 dulse extracts were 36.42 and 38.78 μmol Trolox/g extract. B16-F1 murine skin melanoma cell proliferation was inhibited (p < .05) by 68.5% and 91.9% by grade 1 and 2 dulse extracts at 6.0 mg/mL. The antiproliferative efficacy of grade 2 dulse was greater (p < .05) than grade 1 from 0.375 to 6.0 mg/mL. MAA differences between the grade 1 and 2 dulse extracts likely influenced the antiproliferative efficacies, despite the similar ORAC values.  相似文献   
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