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41.
综述了计算机辅助设计(CAD)/计算机辅助工程(CAE)技术在普通塑料制品制造、汽车轻量化以及航天航空等领域的应用。首先建立产品三维模型并进行塑件分析,初步设计出模具的结构,通过优化得到概念化的模具结构;然后进行注塑模具的详细设计,包括型芯型腔的设计、成型零部件的设计,以及对浇注系统、冷却系统、侧向抽芯、顶出机构的设计,通过充填分析、流动分析、冷却分析、翘曲分析使模具设计趋于完善。使用CAD/CAE仿真技术可以保证塑件模具结构设计的可靠性和高效性,降低了生产成本,提高了产品设计质量。 相似文献
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This paper presents a highly efficient ternary flash ADC, designed using the innovative gate-overlap tunnel FET (GOTFET) at the 45 nm technology node. The proposed GOTFETs have on-state currents Ion more than double, while the off-state currents Ioff remaining at least an order of magnitude lower than the corresponding values of the standard 45 nm CMOS technology with the same width. Replacing MOSFETs with the proposed GOTFETs significantly reduces the static power consumption and improves performance. However, the higher Ion increases the dynamic power as well. To minimize the dynamic power, we propose a novel complementary GOTFET (CGOT) based comparator design. In addition to the inherent advantages of the GOTFET technology, the proposed design further reduces the dynamic power, such that the final power delay product (PDP) is merely 6.3% of the PDP in conventional CMOS comparator design. In addition to the novelty related to the innovative GOTFET devices, there are at least two-fold circuit-level novelty reported in this work. Firstly, we propose a novel CGOT based comparator circuit design, which, in addition to the advantages of GOTFET, further reduces the dynamic power such that the PDP is less than 1/3rd of the original PDP of the conventional comparator designed with GOTFETs. Secondly, the proposed CGOT based ADC requires only 48 transistors to encode the comparator outputs into the 2-bit ternary output, which is 30% lower than the 70 transistors necessary for the 2-bit CMOS based ternary flash ADC designs reported earlier in the literature. We propose an efficient 2-bit ternary flash ADC with a resolution of 50 mV and input quantized to 9 levels. Subsequently, we benchmark the performance of the proposed CGOT ternary flash ADC with the same ADC circuit implemented using the standard 45 nm CMOS technology library, all corresponding devices having the same width. We demonstrate that in addition to the superior performance than the corresponding CMOS ADC, the proposed CGOT ADC design consumes significantly lower power. The overall PDP of the proposed CGOT ADC is merely 6.3% of the PDP in corresponding CMOS design. 相似文献
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针对高温烟气中煤焦的气化行为,本文采用FactSage 6.1计算了煤焦在高温烟气下的高温反应特性,并利用热重分析仪分析了煤焦气化行为。通过沉降炉实验进一步研究了不同温度、气体配比、粒径条件下气体产物的动态析出特性,同时计算了评价指标α、β、LHV值。结果表明:随着温度的升高,气体产物H2和CO的含量增加,β、α、LHV值增大,CH4和CO2的含量下降。在温度为1200℃时,β、α值分别由CO2/CO比为10∶70时的10.80%、5.21%增加到CO2/CO比为50∶30时的24.71%、41.06%。同时,随着CO2/CO比值的增大,高温烟气对煤焦气化反应抑制减弱。通过对比反应温度和粒径对煤焦气化反应的影响,得出反应温度远大于粒径对煤焦气化反应的影响。通过实验验证了向高温烟气中喷吹煤焦制备高品质可燃气体方法的可行性。 相似文献
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将降雨数值预报产品运用到水文预报中已经逐渐成为提高洪水作业预报的预见期的重要手段。为充分了解ECMWF(European Centre for Medium Range Weather Forecasts)和WRF(Weather Research and Forecasting model)2种数值天气预报产品对嘉陵江研究区面雨量预报的预报精度和误差分布,且为增强洪水预报精度的稳健性提供科学支持,采用TS评分、空报率、漏报率、正确率等指标,对嘉陵江地区7个气象分区内的2016年汛期面雨量预报结果进行了检验,分析了不同分区内各检验指标与预报时效的关系。结果表明:ECMWF数值预报产品和WRF数值预报产品均可用于该地区晴雨预报,且2种产品的预报精度随降水等级的增大呈增大趋势,随预报时效的增加呈减小趋势。综合而言,ECMWF数值预报产品对嘉陵江研究区的预报效果更好。 相似文献
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Shahira Said Aly Tsuyoshi Imai Mohamed Salah Hassouna Diem-Mai Kim Nguyen Takaya Higuchi Ariyo Kanno Koichi Yamamoto Rinji Akada Masahiko Sekine 《International Journal of Hydrogen Energy》2018,43(10):5300-5313
The ability of Clostridium butyricum RAK25832 to use casamino acids as a nitrogen source was investigated. Strain RAK25832 showed the capacity to utilize different types of carbon sources. With glucose as a carbon source (10 g/L), the preferred final concentration of casamino acids was 26.67 g/L, with a cumulative hydrogen production, production rate, and yield of 2505 mL H2/L, 160 mL/h, and 1.81 mol H2/mol glucose, respectively. Eighteen metal elements were screened to identify the most important metals for biohydrogen production, and four elements were optimized. The optimal medium composition was MgCl2·6H2O (0.1 g/L), K2HPO4·3H2O (6.67 g/L), NaHCO3 (2.6 g/L), and FeCl2·4H2O (0.002 g/L). Vitamin supplementation of the medium showed no significant effect on hydrogen production. Under the optimized conditions, cumulative hydrogen production reached 3074 mL H2/L. This is the first study to demonstrate the use of casamino acids as a nitrogen source by C. butyricum. 相似文献
49.
Sustainable and efficient food supply chain has become an essential component of one’s life. The model proposed in this paper is deeply linked to people's quality of life as a result of which there is a large incentive to fulfil customer demands through it. This proposed model can enhance food quality by making the best possible food quality accessible to customers, construct a sustainable logistics system considering its environmental impact and ensure the customer demand to be fulfilled as fast as possible. In this paper, an extended model is examined that builds a unified planning problem for efficient food logistics operations where four important objectives are viewed: minimising the total expense of the system, maximising the average food quality along with the minimisation of the amount of CO2 emissions in transportation along with production and total weighted delivery lead time minimisation. A four objective mixed integer linear programming model for intelligent food logistics system is developed in the paper. The optimisation of the formulated mathematical model is proposed using a modified multi-objective particle swarm optimisation algorithm with multiple social structures: MO-GLNPSO (Multi-Objective Global Local Near-Neighbour Particle Swarm Optimisation). Computational results of a case study on a given dataset as well as on multiple small, medium and large-scale datasets followed by sensitivity analysis show the potency and effectiveness of the introduced method. Lastly, there has been a scope for future study displayed which would lead to the further progress of these types of models. 相似文献
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