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51.
作为新兴产业,预制构件厂的设计和运营是实现装配式建筑构件高效率、高质量生产和配送的关键前提要素。而精益设计可以帮助预制构件厂从源头消除浪费、提高生产效率,所以对预制构件厂构建精益设计方案并且评价实施后的效果无疑是一个重点问题。针对以上问题,本文从节约资金能力、生产能力、交付能力、持续改进能力等4个视角构建出了预制构件厂精益设计评价指标体系,采用了AHP-DEMATEL法确定了指标的权重,并用改进TOPSIS法得到最终结果,最后以某预制构件厂为例验证了精益设计评价指标体系的合理性和可行性。 相似文献
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53.
人类在漫长的进化过程中形成了对自然的本能需求,亲生物设计从生物进化的角度以更系统和更合理的方法将自然重新融入现代建筑环境,构建人与场所之间的积极交互。源于光、水、风、植物、动物等自然元素的亲生物色彩设计具有令人愉悦的艺术感染力,动态的视觉效果暗示着蓬勃的生命力,能够系统、清晰地传递复杂的环境信息,引发观者的情感共鸣和情感依恋。从环境疗愈的角度看,具有亲生物特征的色彩设计对改善患者在医疗空间中的体验,激发患者的自我康复能力具有重要意义。亲生物设计是可持续发展设计中不可或缺的一环,两者的结合有助于创造兼具低环境影响和高情感联系的设计,以实现真正和持久的可持续性发展。 相似文献
54.
总结了某800 t/d浮法薄玻璃生产线项目建设的教训与经验,通过项目过程中发生的真实案例,对项目建设中存在的不足进行了深入剖析,并就项目的方案制定、材料与供方选择、建设工期与质量控制等工作提出了改进建议。 相似文献
55.
Jean-Claude Malela-Majika Sandile Charles Shongwe Muhammad Aslam Zhi Lin Chong Eeva Maria Rapoo 《Quality and Reliability Engineering International》2021,37(8):3580-3599
In most applications, parametric monitoring schemes are used to monitor the majority of industrial and nonindustrial processes in order to improve the quality of the outputs or services. However, parametric monitoring schemes are known to underperform when the normality assumption is not met or when there is not enough information about the symmetry or asymmetry nature of the process underlying distribution. Hence, in this paper, a new nonparametric Phase II Shewhart-type double-sampling (DS) monitoring scheme based on the precedence statistic is proposed in order to efficiently monitor quality processes when the underlying process distribution departs from normality. The performance is investigated using the average run length (ARL), standard deviation of the run length (SDRL), expected ARL (EARL) and expected average number of observations to signal (EANOS), and the average sample sizes (ASS) metrics. The latter metrics are computed using Monte Carlo simulation and exact formulae. In general, it is shown that the new DS precedence scheme outperforms the existing basic Shewhart precedence scheme with and without supplementary runs rules in many situations. A real-life illustrative example based on a filling process of milk bottles is provided to demonstrate the application and implementation of the new DS precedence monitoring scheme. 相似文献
56.
Ji Qi Yanhui Li 《International Journal of Adaptive Control and Signal Processing》2021,35(6):1062-1082
In the network environment, the single time-triggered scheme wastes limited bandwidth resources due to all the sampled data are transmitted to the networks, and the single event-triggered scheme may increase system error because of ignoring factors such as changes in network utilization. To reduce the design conservatism, this paper is concerned with the hybrid-triggered L1 fault detection filter design for a class of nonlinear networked control systems (NCSs) described by Takagi–Sugeno (T-S) fuzzy model. Taking the effects of time-triggered scheme and event-triggered scheme into consideration simultaneously, we construct a fuzzy fault detection system. New results on stability and L1 performance are proposed for fuzzy fault detection system by exploiting the Lyapunov–Krasovskii functional and by means of the integral inequality method. Specially, attention is focused on the design of fault detection filter that guarantees a prescribed L1 noise attenuation level . Finally, two examples are presented to demonstrate the effectiveness of the proposed method. 相似文献
57.
Kutele Mabude Jean-Claude Malela-Majika Philippe Castagliola Sandile C. Shongwe 《Quality and Reliability Engineering International》2021,37(2):409-432
An overview of monitoring schemes from a class called generally weighted moving average (GWMA) is provided. A GWMA scheme is an extended version of the exponentially weighted moving average (EWMA) scheme with an additional adjustment parameter that introduces more flexibility in the GWMA model as it adjusts the kurtosis of the weighting function so that the GWMA scheme can be designed such that it has an advantage over the corresponding EWMA scheme in the detection of certain shift values efficiently. The parametric and distribution-free GWMA schemes to monitor various quality characteristics and its existing enhanced versions (ie, double GWMA, composite Shewhart-GWMA, mixed GWMA-CUSUM, and mixed CUSUM-GWMA) have better performance than their corresponding EWMA counterparts in many situations; hence, all such existing research works discussing GWMA-related schemes (ie, 66 publications in total) are documented and categorized in such a manner that it is easy to identify research gaps. Finally, a number of possible future research ideas are provided. 相似文献
58.
59.
Aminul Islam Monoranjan Debnath Rony Mahmudul Islam Emdadul Haque Chowdhury Mohammad Nasim Hasan 《亚洲传热研究》2021,50(3):2339-2361
The present study numerically explores the mixed convection phenomena in a differentially heated ventilated square cavity with active flow modulation via a rotating plate. Forced convection flow in the cavity is attained by maintaining external fluid flow through an opening at the bottom of the left cavity wall while leaving it through another opening at the right cavity wall. A counter-clockwise rotating plate at the center of the cavity acts as an active flow modulator. Moving mesh approach is used for the rotation of the plate and the numerical solution is achieved using arbitrary Lagrangian-Eulerian finite element formulation with a quadrilateral discretization scheme. Transient parametric simulations have been performed for various frequency of the rotating plate for a fixed Reynolds number (Re) of 100 based on maximum inlet flow velocity while the Richardson number (Ri) is maintained at unity. Heat transfer performance has been evaluated in terms of spatially averaged Nusselt number and time-averaged Nusselt number along the heated wall. Power spectrum analysis in the frequency domain obtained from the fast Fourier transform analysis indicates that thermal frequency and plate frequency start to deviate from each other at higher values of velocity ratio (>4). 相似文献
60.
为了更好模拟横断山在气象、植被、土壤、水分等垂直地带性影响下的水文过程,本文采用分布式流域水文模型 WEP,提出反映空间分异特征的垂直带参数化方案,并选择横断山流域 14 个水文控制断面 1960—2015 年的逐月径流数据进行了模拟验证。结果显示,垂直带参数化方案较好地模拟了横断山区的水循环过程;通过两种对照方案和垂直带参数化方案的对比表明,“垂直带参数化方案”比“普通的参数方案”的 NS 提高 0.03、RE 降低1%,比“均一化参数方案”的 NS 提高 0.3、RE 降低 19.6%。通过考虑参数的垂直变化影响,能够提高模型模拟效果,且可更好地反映气象、植被、土壤、水分等信息的垂直地带性,弥补以往水文模型对参数的垂直变化描述不足的问题。 相似文献