Abstract In response to the problem of using different single machines to achieve measurement and detection of existing torque instruments, this article introduces a multifunctional reference torque ...standard and proposes specific steps for torque measurement and detection. This standard machine can be used to detect various existing torque instruments and can solve the problem of using a single machine to achieve the detection of a certain type of torque equipment. After adopting this standard machine and its detection method, experimental data shows that the measurement of the torque transducer can meet the requirements of JJG995-2005 “Static Torque Measuring Machines” and the measurement of the reference torque wrench can meet the requirements of JJG1103-2014 “Reference torque wrench Verification Regulations”.
Abstract
During the verification process of the special axle (wheel) load scales for motor vehicles test using the standard dynamometer method, it is necessary to first apply pressure vertically to ...the load receptor of the axle (wheel) load scales through the axis of the force sensor, which is a prerequisite for subsequent parameter verification work such as indication error. Aiming at the problem of low automation in the lifting and lowering work of force sensors using jacks, this paper introduces a verification device for axle (wheel) load scales based on the automatic loading function and proposes specific automatic loading methods and steps. According to the experimental data after implementation, the verification device has the advantages of high automation and high efficiency, which can replace the existing jack to achieve the lifting and lowering of the force sensor. With this verification device and its automatic loading method, the measurement of the axle (wheel) load scales can meet the requirements of JJG1014-2019 “Special Axle (Wheel) Load Scales for Motor Vehicle Test”.
Airport information weak current system is the core of airport terminal, which is responsible for information interaction, power resource and energy consumption management among subsystems of airport ...terminal. Meanwhile, it is also responsible for main business dispatch management of entire airport terminal. Therefore, starting with basic ant colony algorithm and considering respective advantages of genetic and ant colony algorithms, optimization cycle of the two algorithms is introduced multiple times in this paper. Moreover, after each loop iteration of ant colony algorithm, optimal solution generated by ant colony algorithm will be added to genetic algorithm so that iterative speed of genetic algorithm can be accelerated. Meanwhile, solution calculated by genetic algorithm will be set to better path to update pheromone allocation in ant colony algorithm and achieve parameter adjustment. Experimental test proves that geneticant colony hybrid algorithm proposed in this paper has good convergence and solution efficiency, which can find the shortest path with suitable conditions in complex road networks.
This paper introduced a FPGA design scheme of the Radix-22 in the realization of the FFT processor. This method with the SDF structure was considered to decrease the control complexity, increase the ...utilization factor of the butterfly. The numbers of storage and multiplier were reduced and nonstopping input data could be processed because of the pipeline architecture. At last the architecture was implemented with the Xilinx ISE development tool using VHDL and the balance of different aspects such as speed, resource and storage was tried. Experimentation shows that it is a feasible method to use R22 algorithm to realize FFT transform. (4 pages)
Three-dimensional (3D) nanofabrication techniques are of paramount importance in nanoscience and nanotechnology because they are prerequisites to realizing complex, compact, and functional 3D ...nanodevices. Although several 3D nanofabrication methods have been proposed and developed in recent years, it is still a formidable challenge to achieve a balance among resolution, accuracy, simplicity, and adaptability. Here, we propose a 3D nanofabrication method based on electron-beam lithography using ice resists (iEBL) and fabricate 3D nanostructures by stacking layered structures and those with dose-modulated exposure, respectively. The entire process of 3D nanofabrication is realized in one vacuum system by skipping the spin-coating and developing steps required for commonly used resists. This needs far fewer processing steps and is contamination-free compared with conventional methods. With in situ alignment and correction in the iEBL process, a pattern resolution of 20 nm and an alignment error below 100 nm can be steadily achieved. This 3D nanofabrication technique using ice thus shows great potential in the fabrication of complicated 3D nanodevices.
Personal thermal management, especially heating up the space around human body, consumes substantial global resources. While traditional methods (such as room heaters) for personal heating are mostly ...energy-wasting and eco-unfriendly, ultra-thin textile with localized heating ability has recently gained significant attention. To date, passive radiative heating textiles are designed exclusively for indoor scenario and the coloration remains challenging. Herein, the authors report a colored nanophotonic structure textile (~16 μm thickness) with localized heating ability for both indoor and outdoor environments: (a) solar heating by selectively absorbing sunlight and converting it into heat (maximum absorbance ~ 50%) and (b) passive heating by suppressing radiative heat loss with a low-emissivity outer surface (infrared emissivity ~ 10%). This textile enables a 3.8 °C temperature enhancement of the artificial skin in indoor environment and a 6.3 °C temperature enhancement under sunlight compared with 2-mm-thick black sweatshirt, as well as excellent aesthetics, wearability and manufacturability. This colored textile with simultaneous solar and passive heating abilities is effective for energy-saving personal thermal management, and paves an innovative way to the sustainable development.
Ultra-thin radiative textile with cost-effective localized heating ability has gained significant attention in recent years. However, passive radiative heating textiles to date are designed exclusively for indoor scenario and the coloration remains challenging. The authors report a colored nanophotonic structure textile with localized heating ability for both indoor and outdoor environments: (a) solar heating by selectively absorbing sunlight and converting it into heat and (b) passive heating by suppressing radiative heat loss with a low-emissivity outer surface. Display omitted
•Textile with simultaneous solar (broadband solar absorption) and passive heating abilities (low mid-infrared emissivity).•Ultra-thin textile (~16 μm) with heating ability comparable to thick commercial textiles.•The textile presents various colors (orange, magenta, purple and blue), and excellent wearability.•Facile fabrication involves only simple film deposition and scalable fabrication with roll-to-roll system is practical.
The utilization of such solid wastes as red mud (RM), carbide slag (CS), and fly ash (FA) in the production of environmentally friendly and cheap construction materials is a challenging task. This ...study produced red mud-carbide slag-fly ash (RCF) lightweight aggregate ceramsite by disc pelletizer. The effects of the preparation and curing method on the cylinder crush strength, apparent density, bulk density, water absorption, and softening coefficient of RCF ceramsite samples were experimentally investigated. The curing method was optimized based on XRD, FTIR, TG-DTG, and SEM analyses. The mechanical properties and internal pore structure of ceramsite samples were significantly improved by increasing steam curing temperature, steam curing time, and standing curing time. The optimum curing method implied a 24 h curing at the standing time and 12 h at 80 °C steam curing temperature. RCF ceramsite samples obtained by this method featured an apparent density of 1400 kg/m3, bulk density of 770 kg/m3, and softening coefficient of 0.95. Their cylinder crush strength was increased by 114.3%, and a 1 h water absorption dropped by 17.0% compared to RT-produced samples. This was due to high temperature accelerating the activation of FA and promoting the dissolution of inner spherical beads. This, in turn, accelerated the hydration reaction and increased the amount of C-(A)-S-H gel, which filled the pores and improved the overall density. The increased length of standing curing time improved the ability of RCF ceramsite samples to withstand structural damage caused by high temperatures. This product can be used to prepare light partition walls and light non-load-bearing structural prefabricated members instead of natural gravel. The results provide a theoretical basis for engineering the application of light aggregates produced from solid wastes.
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Many large scientific projects are emerging worldwide with the development of high energy physics nowadays. The indispensable subsystem, helium cryo-plants for such projects require extremely high ...energy consumption and total annual cost (TAC). In order to reduce energy consumption and TAC, multi-objective thermo-economic optimization that adopted non-dominated sorting genetic algorithm-II (NSGA-II) for helium cryo-plants is proposed in this work. As a typical helium liquefaction cycle, Collins cycle is selected as the optimization object. Both the exergetic efficiency (ηEx) and the TAC are set as objective parameters. The decision parameters, which include discharge pressure of compressor, flow fraction of expanders and effectiveness of heat exchangers, are optimized simultaneously. Linear programming technology of multidimensional analysis preference (LINMAP) is utilized as an example to select the optimal solution from the multi-objective optimization results. Compared to the maximum ηEx result, the LINMAP result reduces the TAC by 23.95% at the cost of 9.03% reduction in ηEx. In the proposed approach, eight decision parameters can be optimized simultaneously and the designed cryo-plant considers both economic and thermodynamic criteria, which is feasible for practical engineering project. Besides, alternative solution under limited investment situation is provided.
•A multi-objective optimization method for Collins cycle is presented.•More reasonable solutions for real engineering application are found.•Annual cost distribution is analyzed.•Optimizations of ηEx, Csl and PCsl are proved to be equivalent.•Optimization of y is not equivalent with ηEx.
Advances in electron-beam lithography (EBL) have fostered the prominent development of functional micro/nanodevices. Nonetheless, traditional EBL is predominantly applicable to large-area planar ...substrates and often suffers from chemical contamination and complex processes for handling resists. This paper reports a streamlined and ecofriendly approach to implement e-beam patterning on arbitrary shaped substrates, exemplified by solvent-free nanofabrication on optical fibers. The procedure starts with the vapor deposition of water ice as an electron resist and ends in the sublimation of the ice followed by a “blow-off” process. Without damage and contamination from chemical solvents, delicate nanostructures and quasi-3D structures are easily created. A refractive index sensor is further demonstrated by decorating plasmonic nanodisk arrays on the end face of a single-mode fiber. Our study provides a fresh perspective in EBL-based processing, and more exciting research exceeding the limits of traditional approaches is expected.
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