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1.
文章以“数字电子技术基础”课程为对象,设计了基于教学数据和问卷调查的教学框架。通过学生情况调查和雨课堂教学数据掌握学习状态和学习能力,针对性设计了个性化作业布置、拓展延伸、疫情线上自学跟学双通道等特色教学方式。结课问卷表明教学设计得到了良好评价和认可。  相似文献   
2.
倪泰乐  冉然  祁娜  赵丽  陈彧 《包装工程》2022,43(22):125-133
目的 将数字化服务融入老年患者就诊流程,建立适老化就诊等待服务系统,在APP开发设计研究中实现软件流程优化。方法 依据ERG理论对老年患者在就诊等待过程中的需求点进行分类整理和层次划分。调研目标用户将分析结果融入服务设计理论,为指导软件开发所涉及的医院就诊流程、用户需求痛点,提出系统性的解决策略。基于交互设计原则展开APP界面设计。结论 构建了以老年患者为中心的就诊等待服务系统,帮助提升其等待过程中的自我效能。完善了基于产品使用方式层级的适老化就诊等待服务APP设计策略,为适老化、数字化产品研发提供了新思路;最终产出APP设计实例,提高了老年群体社会参与度,鼓励老年患者自主就诊,帮助其更加轻松地享受信息化时代带来的红利。  相似文献   
3.
《工程爆破》2022,(4):53-57
"黄金分割法"是一种古老的数学方法,它无处不在并造就了事物的和谐美,多年来经常被应用到艺术、摄影、绘画、设计等多个领域,而且得到了意想不到的效果。根据多年的爆破工程实践,将"黄金分割法"与工程爆破实例相结合,应用到露天爆破、高耸建(构)筑物爆破拆除等工程中,取得了很好的爆破效果。  相似文献   
4.
白仁飞  蔡军 《包装工程》2022,43(14):396-402
目的 在新的视角下,提出一种价值创新路径模型,对设计驱动型企业的价值实现方式进行有效补充。方法 通过文献研究,论述了企业关系由价值链到价值网转变的历史趋势;通过比较研究,对价值实现过程中主客体之间的4种关系进行了类比分析,提出了不同主客体关系状态下设计实践的具体表现方式。结果 在价值网络语境下,以价值论为理论依据,从主客体之间的关系入手,构建设计价值创新路径模型。结论 通过分析证明:“主客体统一状态”是企业价值创造的理想状态;主客体关系一直处于动态的变化过程中;客体对主体的“意义”也一直处于动态变化中。在这种动态变化的关系网络中,设计驱动方式已经成为企业创新的重要模式,企业如何捕获并诠释“意义”,成为价值实现的关键所在。  相似文献   
5.
In this work, hydrate based separation technique was combined with membrane separation and amine-absorption separation technologies to design hybrid processes for separation of CO2/H2 mixture. Hybrid processes are designed in the presence of different types of hydrate promoters. The conceptual processes have been developed using Aspen HYSYS. Proposed processes were simulated at different flow rates for the feed stream. A comprehensive cost model was developed for economic analysis of novel processes proposed in this study. Based on the results from process simulation and equipment sizing, the amount of total energy consumption, fixed cost, variable cost, and total cost were calculated per unit weight of captured CO2 for various flow rates of feed stream and in the presence of different hydrate promoters. Results showed that combination of hydrate formation separation technique with membrane separation technology results in a CO2 capture process with lowest energy consumption and total cost per unit weight of captured CO2. As split fraction and heat of hydrate formation increases, the share of hydrate formation section in total energy consumption increases. When TBAB is applied as hydrate promoter, due to its higher hydrate separation efficiency, more amount of CO2 is captured in hydrate formation section and consequently the total cost for process decreases considerably. Hybrid hydrate-membrane process in the presence of TBAB as hydrate promoter with 29.47 US$/ton CO2 total cost is the best scheme for hybrid hydrate CO2 capture process. Total cost for this process is lower than total cost for single MDEA-based absorption process as the mature technology for CO2 capture.  相似文献   
6.
A large-scale high-precision scan stage is important equipment in the industrial productions of micro-fabrication such as flat panel display (FPD) lithography systems. Designing controllers for multi-input multi-output (MIMO) systems is time-consuming and needs experience because of the interaction between each axis and many controller tuning parameters. The aim of this study is to develop a peak filter design method based on frequency response data to reduce repetitive disturbance. This data-based approach does not use the model and only uses the frequency response data of the controlled system and the disturbance spectrum calculated from the scanning error data (Contribution 1). The peak filter is designed by convex optimization and satisfies robust stability conditions for six-degree-of-freedom systems (Contribution 2). The control performance of the designed peak filter is experimentally demonstrated with an industrial MIMO large-scale high-precision scan stage in reducing the scanning error of the main stroke of the translation along the x-axis (Contribution 3).  相似文献   
7.
Dark fermentation of sugarcane vinasse can be used as a “cleaning” step to remove sulfate prior to methanogenesis because sulfidogenic conditions can be successfully established in parallel with biohydrogen production. Using a 22 central composite rotational design (CCRD) and response surface methodology (RSM), this study assessed the impacts of bicarbonate and sulfate availability on the establishment of sulfidogenesis in the thermophilic (55 °C) fermentation of vinasse in batch reactors, equally assessing the impacts on biohydrogen evolution. CCRD-RSM results indicated the favoring of biohydrogen production at the lowest sulfate and bicarbonate concentrations, whilst the opposite was observed for sulfidogenesis. Glycerol, lactate, and hydrogen were the preferential electron donors utilized by sulfate-reducing bacteria (SRB), whilst ethanol was markedly consumed only at high sulfate concentrations. SRB were inhibited by sodium when dosing excess NaHCO3 and Na2SO4. Complementary tests revealed maximum biohydrogen production (2.40 mmol) out of the CCRD, at pH exceeding 7.5 with no interference of sulfidogenesis. Non-efficient biohydrogen production was observed at low pH (<5.0; ~1.90 mmol) because the uptake of lactate was inhibited. Meanwhile, homoacetogenesis was established under intermediate pH range (5.5–6.5), as revealed by the accumulation of acetate (up to 2.5 g L?1). 16S rRNA gene amplicon sequencing further revealed the genera Thermoanaerobacterium/Pseudoclostridium, Desulfotomaculum/Desulfohalotomaculum and Sporomusaceae/Moorella as the main biohydrogen-producing, sulfate-removing and biohydrogen-consuming (homoacetogens) microbial groups, respectively. Hence, using a single inoculum source, vinasse may provide a butyrate-rich (along with biohydrogen-rich biogas) or a sulfate-free and acetate-rich fermented effluent, depending mainly on proper pH control.  相似文献   
8.
曹鸣  杨春  周沛桦 《包装工程》2022,43(22):395-404
目的 探究消费者对共享单车的需求偏好,获取用户和设计师对产品的认知差距,并提出相应的设计决策,为共享单车以及两轮车行业的产品创新提供启迪与参考。方法 从设计师思维与消费者偏好的视角出发,对共享单车消费者偏好的各项设计原则(属性)进行细致分类,建立8个评价维度与41个评价特征,采用KANO模型对有效回收样本进行定量统计及定性分析。结果 基于前期调研与KANO模型分析,提出后共享时代单车设计的相关策略。结论 在后共享单车时代下,设计师需要根据用户真实的产品偏好与体验感知进行设计策略的研究,以设计出真正满足用户需求和体验期望的产品。同时也证明KANO模型作为一种阐明用户不同感性需求的方法,有助于设计师进行设计决策的综合判断,提升设计的竞争力。  相似文献   
9.
10.
This paper focuses on thermal destratification and pressurisation inside thermally stratified storage tanks by continuous gas bubbling. The primary purpose of doing these studies is to better understand the effect of bubble dynamics on thermal destratification and quantify the extent of destratification. The volume of fluid and interface compression method of OpenFOAM CFD code is utilised for the present analysis. Different values of inlet gas velocities (Vg), orifice diameters (do), and arrangement of the orifices in triangular and square fashion with different pitches (p/do) are considered. In addition, the effect of gravitational forces (g/ge) on thermal destratification is also reported. For all these cases, the effectiveness of thermal destratification is quantified in terms of a newly defined parameter, the destratification index (Id). For Vg = 1 m/s, the Id value is maximum compared to lower Vg values. It is seen that when the gas velocity increased from 0.3 m/s to 1.0 m/s, the average effectiveness in thermal destratification (Idavg) and pressure at the ullage increased by 44.38% and by 64.81%, respectively. The Idavg and pressure at ullage increased by 96.29% and 14.91%, respectively, when the g/ge ratio changed from 0.3 to 3. Compared to the triangular arrangement with p/do = 10, the calculated Idavg increased by 30.67% when gas inlets were arranged with a square pitch of 10. For p/do = 4, 6 and 8, the increments in Idavg are of the order of 12.86%, 19.43% and 21.92%, respectively, for gas inlets arranged in a square fashion as compared to the triangular arrangement. It is found that continuous bubbling with gas inlets arranged in square pitch p/do = 10 gives higher effectiveness in thermal destratification. Thus, by these studies, one can develop a thermal destratification mechanism with continuous bubbling for optimum performance. Also, these studies give an overall idea of sparger design for getting the correct gas flow rate for thermal destratification within the cryogenic liquid storage tanks.  相似文献   
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