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81.
单星 《工具技术》2014,(6):87-90
在油井管特殊扣产品的加工过程中,拧接是一个重要工序,而拧接设备是否具有自动判定的功能,自动判定方法合适与否,都会对生产节奏和质量控制产生影响。本文介绍了一种自动判定的方法,通过对拐点的扭矩数值、圈数的判断,再加上一些防错手段,实现对特殊扣拧接曲线的自动判定。  相似文献   
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Hydropower energy generation depends on the available water resources. Therefore, planning and operation of the water resource systems are paramount tasks for energy management. Since reservoirs are one of the important components of water resources systems, extracting optimal operating policies for proper management of energy generated from these systems is an imperative step. Optimizing reservoir system operation (ORSO) is a non-linear, large-scale, and non-convex problem with a large number of constraints and decision variables. To solve ORSO problem effectively, a robust diversity-based, sine-cosine algorithm (RDB-SCA) is developed in the present study by introducing several strategies to balance the global exploration and local exploitation ability and to achieve accurate and reliable solutions. An efficient linear operation rule is coupled with the RDB-SCA to maximize the energy generation. The proposed method is then applied to a real-world, multi-reservoir system to extract optimal operational policies and, consequently, maximize the energy production. It is shown that the RDB-SCA is able to generate 24, 14, and 6% more energy than the original SCA, respectively for 2-, 3-, and 4-reservoir systems. The present findings are useful to suggest guidelines for efficient operation of hydropower multi-reservoir systems. This paper is supported by https://imanahmadianfar.com/codes.

  相似文献   
84.
Bitumen extraction from oil sands is carried out in large separation cells using a water-based extraction process. Controlling the Bitumen-froth and Middlings interface in these cells at an optimum level provides significant economical and environmental benefits. Traditional sensors are not reliable in estimating this interface level and novel vision-based sensors have been developed previously to overcome this problem. These sensors estimate the interface level and its confidence for separation cells with a single sight glass. The confidence value only represents the turbidity of the interface and hence cannot be used for control decision making in all process conditions. The current work describes an image differencing algorithm for interface level detection which also facilitates the computation of a confidence estimate that is accurate in most process situations. The confidence value is computed based on noise statistics, an appropriately chosen edge detection method and a change detection algorithm. Another significant advantage of the algorithm is that both the interface level and the confidence estimation procedures can be extended in a straight-forward manner to handle the presence of multiple sight glasses. Off-line results show that the algorithm accurately detects the interface level in normal process conditions (with high confidence values) and outputs correct confidence values in other situations with very low false-positive and false-negative error rates. On-line industrial implementation results show that the vision sensor tracks the interface level very closely and results in significant automation of plant.  相似文献   
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Fine bamboo strips (BSs) have been laid on polypropylene (PP) web, stacked, and compression molded to prepare unconsolidated light-weight (0.312 g/cm3) composites. Composite properties are superior compared with jute-based composites and bamboo strips show potential to replace fiberglass or polyurethane in composites. Flexural strength, modulus, offset yield load, and Noise Reduction Coefficient (NR) of the BS–PP composites are 5.8×, 2.9×, 6.5×, and 1.4× higher, respectively, compared to jute–PP composites. Bamboo-based non-consolidated composites with excellent mechanical and sound absorption properties utilizing the methods described in this research provide an opportunity to manufacture functional composites with bio-based materials leading to reduction of environmental pollution and sustainable manufacturing.  相似文献   
87.
This article provides a comprehensive overview of oxygen (17O) magnetic resonance spectroscopy and imaging, including the advantages and challenges offered by the different methods developed thus far. The physiological role and relevance of oxygen, and its participation in aerobic metabolism, are addressed to emphasize the importance of the investigations and the efforts related to these developments. Furthermore, a number of methods employed in the determination of the cerebral metabolic rate of oxygen in neural cells will be presented, focusing primarily on methodologies enabling absolute quantification.  相似文献   
88.
Use of cysteamine hydrochloride (Cys-HCl) protected gold nanorods (GNRs) as efficient carrier of widely used anti-cancer drug doxorubicin using folic acid as navigational molecule is presented in this work. GNRs were found to have excellent drug loading capacity of >97 %. A detailed comprehension of in vitro drug release profile under ideal physiological condition was found to obey 1st order kinetics at pH 6.8, 5.3 and 7.2, an ideal milieu for drug delivery to solid tumours.  相似文献   
89.
The influences of annealing effects have been explored on the crystallinity, morphology, optical and magnetic properties of Ag–ZnO nanostructures prepared by a simple sol–gel method. X-ray powder diffraction, scanning electron microscope, high resolution transmission electron microscope (HRTEM), vibrating sample magnetometer and photoluminescence spectroscopy (PL) have been used to characterize the crystal structures, surface morphology, magnetic and optical properties of the pure ZnO and Ag–ZnO nanostructures respectively. The synthesized Ag–ZnO nanostructures are found to have hexagonal wurtzite crystal structures and their grain size increases while lattice strain decreases on annealing. From HRTEM observation, it is found that the annealed samples show nanorod like structures with Ag nanoparticles (NPs) embedded on the surface. Due to annealing effect, Ag–ZnO shows higher saturation magnetization at room temperature.  相似文献   
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