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91.
This paper develops an economic order quantity model for non-instantaneous deteriorating items with and without shortages to investigate the performance of the vendor-managed inventory (VMI) system. This model is developed for a two-level supply chain consisting of a single supplier and single retailer with a single non-instantaneous deteriorating item. A numerical example and sensitivity analysis are provided to illustrate how increasing or reducing the related parameters change the optimal values of the decision variables of the two proposed models. The results show that VMI works better and charges lower cost in all conditions.  相似文献   
92.
Multimedia Tools and Applications - With the rapid development of detecting violent behaviors in surveillance cameras, requests on systems that automatically recognize violent events are expanded....  相似文献   
93.
Analog Integrated Circuits and Signal Processing - A new circuit-level methodology called input controlled leakage restrainer transistor (ICLRT) compatible with single threshold CMOS technology is...  相似文献   
94.
The Journal of Supercomputing - Due to high and unpredictable connection delays, privacy gaps, and traffic load of networks connecting cloud computing to end users in many of the Internet of Things...  相似文献   
95.
Pattern Analysis and Applications - Outlier or anomaly detection is an important branch of data analysis that becomes a crucial task in many application domains. Data objects which significantly...  相似文献   
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Architected materials with nano/microscale orders can provide superior mechanical properties; however, reproducing such levels of ordering in complex structures has remained challenging. Inspired by Bouligand structures in nature, here, 3D printing of complex geometries with guided long-order radially twisted chiral hierarchy, using cellulose nanocrystals (CNC)-based inks is presented. Detailed rheological measurements, in situ flow analysis, polarized optical microscopy (POM), and director field analysis are employed to evaluate the chiral assembly over the printing process. It is demonstrated that shear flow forces inside the 3D printer's nozzle orient individual CNC particles forming a pseudo-nematic phase that relaxes to uniformly aligned concentric chiral nematic structures after the flow cessation. Acrylamide, a photo-curable monomer, is incorporated to arrest the concentric chiral arrangements within the printed filaments. The time series POM snapshots show that adding the photo-curable monomer at the optimized concentrations does not interfere with chiral self-assemblies and instead increases the chiral relaxation rate. Due to the liquid-like nature of the as-printed inks, optimized Carbopol microgels are used to support printed filaments before photo-polymerization. By paving the path towards developing bio-inspired materials with nanoscale hierarchies in larger-scale printed constructs, this biomimetic approach expands 3D printing materials beyond what has been realized so far.  相似文献   
99.
Conventional sliding mode control (SMC) has been extensively applied in controlling spacecrafts because of its appealing characteristics such as robustness and a simple design procedure. Several methods such as second-order sliding modes and discontinuous controllers are applied for the SMC implementation. However, the main problems of these methods are convergence and error tracking in a finite amount of time. This paper combines an improved dynamic sliding mode controller and model predictive controller for spacecrafts to solve the chattering phenomenon in traditional sliding mode control. To this aim, this paper develops dynamic sliding mode control for spacecraft’s applications to omit the chattering issue. The proposed approach shows robust attitude tracking by a set of reaction wheels and stabilizes the spacecraft subject to disturbances and uncertainties. The proposed method improves the performance of the SMC for spacecraft by avoiding chattering. A set of simulation results are provided that show the advantages and improvements of this approach (in some sense) compared to SMC approaches.  相似文献   
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