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81.
Key performance indicators have become a common tool in bioprocess development, as they allow an objective and independent rating and ranking of process alternatives screened. A disadvantage of all key performance indicators developed so far is their strong focus on costs, which makes them neglect the influence of the production rate on the profit of the process. But, since both production costs and production rate have an equally strong impact, both should be considered when decisions have to be made. Therefore, two new key performance indicators are introduced in this work, one for batch and one for continuous processing. They combine product yield, purity performance, variable manufacturing costs, and production rate to one objective. Thereby, misguided trade‐offs between these four individual measures can be replaced by one key performance indicator. This ensures a systematic development of biochemical downstream processes.  相似文献   
82.
云制造环境下服务监管角色的评估与选择   总被引:1,自引:0,他引:1  
为加强对云制造环境下服务模式的监管,在分析概括已有三类制造服务模式的基础上,从安全性的角度考虑,提出一种基于可信第三方监管的云制造服务模式,并针对第三方监管角色的评估与选择问题,从三个维度构建其可信评估指标体系,采用网络分析法进行计算。通过实例分析了云制造环境下可信第三方服务监管角色评估与选择的具体过程。  相似文献   
83.
A chitosan-based carbon dioxide (CO2) indicator was developed to monitor freshness or quality of packaged foods during their storage, as elevated CO2 levels inside a package is one of the prime indicators of microbial spoilage of food. The objective of this proof-of-concept study, therefore, was to develop a chitosan-based CO2 indicator and to investigate its performance in different operating environments. For the enhancement of signal strength of indicator, 2-amino-2-methyl-1-propanol (AMP) was used as an additive to the chitosan solution. Aqueous chitosan–AMP suspensions were prepared by addition of chitosan (0.1%, 0.2% and 0.4%) and AMP (0%, 5%, 10% and 20%) to distilled water at pH 7.0. Thereafter, the aqueous chitosan suspensions were incubated under 100% and 20% CO2 test atmospheres. The aqueous solubility of chitosan, which in turn impacts the degree of transparency of the suspension, was tested at different pHs and time intervals, spectrometrically. The transparency of 0.2% chitosan aqueous suspension increased dramatically below pH 6.5 under 20% or 100% CO2 incubation. The addition of a 5% AMP concentration to the chitosan suspension was found optimal for maximum CO2 absorption and this, therefore, increased transparency by more than 90%.  相似文献   
84.
《Planning》2016,(4)
目的 探讨子宫下段受累对Ⅰ期子宫内膜癌术后放疗患者的预后作用。方法 回顾性分析1999年1月至2012年12月在北京协和医院进行术后放疗的Ⅰ期子宫内膜癌患者265例,中位年龄53岁,病理类型主要为子宫内膜样腺癌(226例,85.3%)。根据病理结果是否有子宫下段受累分为两组:子宫下段受累组和子宫下段未受累组,比较两组患者的预后因素和临床治疗结果,并对其中的高危和高中危患者进行亚组分析。主要研究终点包括总生存率、无进展生存率、局部区域复发率、远处转移率和治疗失败率。使用Kaplan-Meier法统计生存率,不同组间生存率的比较使用Log-rank检验,使用Cox比例风险回归模型进行预后因素分析。结果 所有Ⅰ期内膜癌患者的5年总生存率和无进展生存率分别为92.8%和89.7%,5年局部区域复发率、远处转移率和治疗失败率分别为4.5%、6.4%和7.8%。单因素分析显示,子宫下段受累是影响总生存率和无进展生存率的相关因素(P= 0.015,0.035)。Cox比例风险回归模型显示,子宫下段受累组患者的总生存率和无进展生存率更低(P=0.041, RR=0.346, 95% CI: 0.125~0.959; P=0.041, RR=0.411, 95% CI: 0.175~ 0.963)。亚组单因素分析显示,在高危和高中危患者中,子宫下段受累是影响治疗失败率的相关因素(P=0.034)。结论 子宫下段受累可能是影响Ⅰ期内膜癌辅助放疗患者总生存率和无进展生存率的不良预后因素;在高危和高中危患者中,子宫下段受累主要与治疗失败的发生相关。  相似文献   
85.
Indoor localization systems are becoming very popular because they enable the creation of very interesting location-based applications. This paper provides a short introduction about localization systems based on a sensor network and the actual state of the art. Important topics related to indoor localization like the necessary infrastructure, available technologies and their expected accuracy are treated. Additionally, the results of previous work referred to the performance evaluation of localization algorithms are shortly described. Finally, some ideas related to further investigations are presented.  相似文献   
86.
Transitioning to sustainable energy systems is an overriding challenge for small islands. Indeed, these territories must succeed within the next decades with the objective of energy independence and transitioning to a sustainable situation. In this research, a statistical approach is performed to explore and discuss a comprehensive study on small islands' sustainability from the standpoint of renewable energy. It is about identifying whether small islands are moving toward a sustainability path. Three steps are necessary to achieve this. A principal components analysis (PCA) is first investigated to identify which explanatory variables have a significant contribution on the percentage of data variance. Then, PCA-based hierarchical clustering highlights the island organization in two different years (2010 and 2014). It is a panel of 35 Small Islands Developing States (SIDS) that served as a basis for the PCA and classification. Finally, a sustainability indicator is proposed to qualify the level of sustainability of each group of islands. Sustainability is understood through the lens of the share of renewables, the electricity situation, economic development and geographical localization. The obtained results clearly show that the dynamics of transition is not clearly engaged for the small islands. Most of them have actually become more vulnerable during the 2010–2014 time span.  相似文献   
87.
88.
The aim of this paper is to measure and benchmark the environmental performance of Portuguese utilities jointly active in the three sectors of water supply, wastewater collection and solid waste management. To do so, we suggest the use of a traditional (optimistic) directional distance Benefit of the Doubt index. We complement the analysis by considering also the pessimistic version of the proposed BoD and by implementing a robust and conditional approach. The obtained results show that there is space for improvement in the pressure balance of these utilities, especially for small and very large units, mostly operating in urban areas.  相似文献   
89.
水泵转子径向圆跳动检测数据修正   总被引:1,自引:0,他引:1  
针对应用千分表和电涡流传感器进行水泵转子径向圆跳动检测时,检测结果出现正弦变化规律的现象,分析了安装偏心误差对检测结果的影响原理,建立了相应的数学模型.运用最小二乘拟合法计算出变化曲线的幅值及初相位,从而消除偏心误差实现误差分离.结果表明,当将所提方法应用在水泵转子径向圆跳动检测的工程实践中时,可以有效消除安装偏心引起的误差,从而提高检测精确度.拟合平方和误差约为0. 000 9,所提方法可以广泛应用于轴类工件的检测实践.  相似文献   
90.
矿井通风系统的最优方案的选择是一个多因素多目标决策问题,目前主要应用的数学方法理论有模糊数学、灰色系统理论和层次分析法等方法,但上述方法均存在计算量较大的问题。计分法是一种在已给定的多个备选方案中,且备选方案各项指标的权重已经确定的基础上进行计分选择的方法,该方法计算简便,概念直观,计算过程可由Excel办公软件完成。结合某矿山矿井通风工程实例,从技术先进性、安全可靠性和经济合理性三个方面12个指标进行了方案选优分析,并与灰色关联分析法进行了比较。计分法也可以应用于其他工程方案的选优。  相似文献   
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