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51.
In the era of digitalization, there are many emerging technologies, such as the Internet of Things (IoT), Digital Twin (DT), Cloud Computing and Artificial Intelligence (AI), which are quickly developped and used in product design and development. Among those technologies, DT is one promising technology which has been widely used in different industries, especially manufacturing, to monitor the performance, optimize the progresses, simulate the results and predict the potential errors. DT also plays various roles within the whole product lifecycle from design, manufacturing, delivery, use and end-of-life. With the growing demands of individualized products and implementation of Industry 4.0, DT can provide an effective solution for future product design, development and innovation. This paper aims to figure out the current states of DT research focusing on product design and development through summarizing typical industrial cases. Challenges and potential applications of DT in product design and development are also discussed to inspire future studies.  相似文献   
52.
The present article elaborates the Graetz problem for the Robertson-Stiff fluid model with imposed iso-thermal conditions. The closed-form expression of Robertson-Stiff fluid velocity is obtained. Employing the classical separation of variables approach, the energy equation of the said problem is reduced into an eigenvalue problem. The solution of the eigenvalue problem is developed numerically via the MATLAB built-in algorithm BVP4C. The constants appearing in series solutions are computed by Simpson's rule. The special case of this analysis with appropriate scaling is also applicable for the Bingham, power-law, and Newtonian fluid models. The impact of the dissipation function on Nusselt numbers and mean temperature is also considered. The pictorial representation of average temp7erature and Nusselt number are discussed in the presence of the plug radius, power-law index, and Brinkman number. It is observed that the presence of the plug radius and power-law index delay the prevalence of fully developed conditions for the Nusselt number. Moreover, the local Nusselt number for channel confinement attains higher values as compared with tube confinement. The present investigation has numerous applications in the field of engineering, nanotechnology, biomedical sciences, and development of several thermal types of equipment or microfluidic devices.  相似文献   
53.
Nearly half of patients with advanced and metastatic melanomas harbor a BRAF mutation. Vemurafenib (VEM), a BRAF inhibitor, is used to treat such patients, however, responses to VEM are very short-lived due to intrinsic, adaptive and/or acquired resistance. In this context, we present the action of the B-Raf serine-threonine protein kinase inhibitor (vemurafenib) on the glycans structure and metallomics profiles in melanoma cells without (MeWo) and with (G-361) BRAF mutations. The studies were performed using α1-acid glycoprotein (AGP), a well-known acute-phase protein, and concanavalin A (Con A), which served as the model receptor. The detection of changes in the structure of glycans can be successfully carried out based on the frequency shifts and the charge transfer resistance after interaction of AGP with Con A in different VEM treatments using QCM-D and EIS measurements. These changes were also proved based on the cell ultrastructure examined by TEM and SEM. The LA-ICP-MS studies provided details on the metallomics profile in melanoma cells treated with and without VEM. The studies evidence that vemurafenib modifies the glycans structures and metallomics profile in melanoma cells harboring BRAF mutation that can be further implied in the resistance phenomenon. Therefore, our data opens a new avenue for further studies in the short-term addressing novel targets that hopefully can be used to improve the therapeutic regiment in advanced melanoma patients. The innovating potential of this study is fully credible and has a real impact on the global patient society suffering from advanced and metastatic melanomas.  相似文献   
54.
The increasing threat to environmental sustainability as a result of greenhouse gas (GHG) emissions from fossil fuel base power plants has necessitated the need to find sustainable energy sources to meet the world's energy demands. This study focuses on assessing the potential of a hybrid power plant for the production of electricity, hydrogen for the production of fertilizer for agricultural activities, farmland irrigation, environmental impact as well as its employment potential in northern Ghana. The Shannon entropy weight and TOPSIS multi-criteria decision-making approach were adopted to rank and identify the optimal configuration out of five possible options for the study area. Results from the simulation show that the winning system, i.e., Hydro + Battery system would generate a total electricity of 1,095,679 kWh/year. A cost of electricity of 0.06 $/kWh with an operating cost (OC) of $18,318 was recorded for the winning system. The total produced hydrogen by the optimum configuration is 8816 kg/year at a levelized cost of hydrogen (LCOH) of 4.47 $/kg. The quantity of low-carbon fertilizer that can be produced from the produced hydrogen is also assessed. The optimum configuration also recorded an employment potential of 4 persons in 25 years. A total GHG equivalence of 383.49 metric tons of CO2 equivalent indicating the level of emissions that will be avoided should the optimum system be used to meet the demands specified in this study was obtained.  相似文献   
55.
采用溶胀实验及计算机HSPiP软件对牌号为Levapren 800的乙烯-乙酸乙烯酯硫化胶的溶度参数进行了研究。结果表明,单一溶剂与混合溶剂都可用于Levapren 800硫化胶溶度参数的测定,用溶胀法测得其一维溶度参数(δt)为18.90~19.25(J/cm3)1/2。通过HSPiP软件测得Levapren 800硫化胶的δt为19.97(J/cm3)1/2;三维溶度参数的色散力、极性力和氢键力溶度参数分别为18.20,5.50,6.10(J/cm3)1/2。利用三维溶度参数可以预测Levapren 800硫化胶在标准实验油中的溶胀行为;相对能量差对预测聚合物在溶剂中的溶胀性能方面具有一定的应用价值。  相似文献   
56.
随着我国高等学校各项建设工作的大力推进,实验设备的需求也逐渐丰富起来。传统的化学工程专业实验设备的控制简单,与现今的大工业生产的装置自动化程度相比,有一定的脱节。这对于高校培养具有创新能力的"技术型"和"应用型"人才是不利的。华东理工大学化工学院的化学工程与工艺专业实验中心自主设计具有计算机控制的,能适应本专业学生的大型化工流程实验装置——乙苯负压脱氢制苯乙烯装置,运用MCGS工控组态软件对乙苯负压脱氢制苯乙烯装置进行自动控制系统的设计,实现了对脱氢装置的实验过程的监控,从而达到了实验的要求。  相似文献   
57.
利用脱盐水间接冷凝尾气中的水蒸气以减少白雾的排放和回收尾气的低温位余热,同时使用ASPEN PLUS软件对尾气洗涤塔及余热回收过程进行模拟。结果表明,该软件模拟结果与现场测量参数较为吻合,可用于指导生产,并为装置改造提供依据。  相似文献   
58.
利用Origin软件中的解析功能,将中低温煤焦油样品的模拟蒸馏曲线转化为类实沸点蒸馏曲线。类实沸点蒸馏曲线是模拟蒸馏曲线的导函数曲线,是沸点与相应沸点下物质含量的关系图,与实沸点蒸馏曲线类似。通过类实沸点蒸馏曲线可知,随着终温的升高,轻质组分减少,重油增加,沥青含量由30%左右逐渐增加到50%;在350~420℃类实沸点曲线皆出现波峰,波峰沸点物质含量随着煤样热解终温的升高而依次减少。中低温热解以解聚反应为主,高温高能量有利于高键能键的断裂,低温低能量有利于低键能键的断裂。  相似文献   
59.
据哈萨克斯坦天然气气质的特点,提出采用膨胀制冷的深冷工艺回收天然气凝液的方案;并基于Aspen PLUS及EDR软件进行流程模拟及设备初选。模拟结果表明,该方案具有工艺简单、投资低、能耗低及收益高的优点。  相似文献   
60.
卢敏 《广州化工》2014,(10):178-180,188
应用计算流体力学ANSYS-CFX软件对同心结构液体分配器和偏心结构分配器的流场进行了模拟。计算结果的对比分析表明:在相同条件下,偏心分配器的流体均布性能良好,液体分配更均匀。模拟结果与实验数据相吻合,说明本文所采用的方法及模型是可行的,为分布器的研究开发,提供一种比较经济科学的模拟预测方法。  相似文献   
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