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Lean Product Development Process with Design Verification Stages in the Value Stream of Automotive Industry 认领
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作者 Fuat Ali Paker 《交通科技期刊(英文)》 2021年第1期37-60,共24页
In the automotive industry, lean project</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Ver... In the automotive industry, lean project</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> and innovation creation come to life by being updated under the control of systematic interdisciplinary process flows. The lean product development process that changes the shell, defined under the light of the variables created by the competitive conditions, is today measured by the value flow efficiency and the global market spread of the final product. Consequently, the lean product development approach, which aims to identify and purify all the wastes that do none value or create value to the system or cause burdens in the new product development process, is shaped by step-by-step approvals in the flow. In the main automotive industry company practices within the scope of the research (3 national, 3 international), the beginning of the concept of lean in design is to define and optimize the steps in the product development process under the value stream map. Therefore, the product function for which the customer has paid for, the function of the new product or the physical structure used to meet the needs in question, the comfort, life, experience, innovations of the scope that constitute the new product concept are planned and verified and implemented in the simplified automotive design stages at the beginning of the lean product development process. In this research, initial automotive design objectives and stages are at the focal point of the innovation and added value creation brought by the concept of </span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">“</span></span></span></span><span style="font-family:Verdana;"><span sty 展开更多
关键词 Design Management Design Verification Automotive Design Lean Product Development Value Stream Automotive Industry
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Cyclomatic Complexity-Based Encapsulation, Data Hiding, and Separation of Concerns 认领
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作者 Charles W. Butler Thomas J. McCabe 《软件工程与应用(英文)》 2021年第1期44-66,共23页
<div style="text-align:justify;"> <span style="font-family:Verdana;">Three design principles are prominent in software development-encapsulation, data hiding, and separation of concerns... <div style="text-align:justify;"> <span style="font-family:Verdana;">Three design principles are prominent in software development-encapsulation, data hiding, and separation of concerns. These principles are used as subjective quality criteria for both procedural and object-oriented applications. The purpose of research is to quantify encapsulation, data hiding, and separation of concerns is quantified using cyclomatic-based metrics. As a result of this research, the derived design metrics, coefficient of encapsulation, coefficient of data hiding, and coefficient of separation of concerns, are defined and applied to production software indicating whether the software has low or high encapsulation, data hiding, and separation of concerns.</span> </div> 展开更多
关键词 Object-Oriented Design Methods RELIABILITY Complexity Measures Software Design ENCAPSULATION Information Hiding Separation of Concerns McCabe Metrics Coefficient of Encapsulation Coefficient of Data Hiding Coefficient of Separation of Concerns
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文章速递Precision Engineering Design Process for Optimal Design Based on Engineering Sciences 认领
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作者 Amir Javidinejad 《机械工程研究(英文)》 2021年第1期14-21,共8页
Concepts of precision engineering design process for optimal design where engineering sciences contribute in the successful good design are elaborated in this paper.Scientific theory and practicality are discussed in ... Concepts of precision engineering design process for optimal design where engineering sciences contribute in the successful good design are elaborated in this paper.Scientific theory and practicality are discussed in this paper.Factors necessary for a complete product or systems design are detailed and application of mathematical design optimization in producing a good design are shown.Many applicable engineering design examples are itemized to show relevancy of the optimal design theory to engineering design.Future trends of optimal design with respect to the 4th industrial revolution of digitization are presented.Paper sets to elaborate that most of the engineering and scientific design problems can be optimized to a good design based on many new/advanced optimization techniques. 展开更多
关键词 Optimal design Good design Optimization of design Digitization in design
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设计教育的路径及策略探析: 创新人才培养的新视角 认领
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作者 陈鹏 黄荣怀 《电化教育研究》 北大核心 2021年第3期18-26,共9页
创新能力是国家、组织及个人长足发展的关键力量,如何培养创新人才是当前教育发展的重要议题。设计作为一种创造力活动,是实现创新的重要途径和有效方式。文章基于设计与创新的相互依存关系,分析了设计及设计教育在促进创新人才的知识... 创新能力是国家、组织及个人长足发展的关键力量,如何培养创新人才是当前教育发展的重要议题。设计作为一种创造力活动,是实现创新的重要途径和有效方式。文章基于设计与创新的相互依存关系,分析了设计及设计教育在促进创新人才的知识、思维与人格方面发展的价值与意义,以此论证了设计教育发展的必然性。在此基础上,梳理了设计教育由家庭师徒传承的教育形态发展到知识网络时代以创新为目标的设计素养教育形态,提出了不同教育阶段创新人才培养的途径,高等教育阶段一方面可开设专门的设计相关课程,另一方面可将设计与其他学科课程融合,以设计思维开展教育教学实践;基础教育阶段通过艺术与设计、设计与技术为主的设计课程,与学科课程融合的课程以及创客教育的途径来开展设计教育。在开展设计教育过程中,教师以设计思维方法为创新变革教学的策略和方法,通过整合设计素养与学科素养作为培养目标,由简单到复杂来设计教学内容,并在多元泛在化的课程中指导学生以设计思维方法来完成实践活动,促进学生创新能力的养成。 展开更多
关键词 创新人才培养 设计 设计教育 设计思维
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Phase plane design based fast altitude tracking control for hypersonic flight vehicle with angle of attack constraint 认领
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作者 Yang LIU Chaoyang DONG +1 位作者 Wenqiang ZHANG Qing WANG 《中国航空学报:英文版》 SCIE EI CAS CSCD 2021年第2期490-503,共14页
In this paper, fast setpoint altitude tracking control for Hypersonic Flight Vehicle(HFV)satisfying Angle of Attack(AOA) constraint is studied with a two-loop structure controller, in the presence of parameter uncerta... In this paper, fast setpoint altitude tracking control for Hypersonic Flight Vehicle(HFV)satisfying Angle of Attack(AOA) constraint is studied with a two-loop structure controller, in the presence of parameter uncertainties and disturbances. For the outer loop, phase plane design is adopted for the simplified model under Bang-Bang controller to generate AOA command guaranteeing fast tracking performance. Modifications based on Feedback-Linearization(FL) technique are adopted to transform the phase trajectory into a sliding curve. Moreover, to resist mismatch between design model and actual model, Fast Exponential Reaching Law(FERL) is augmented with the baseline controller to maintain state on the sliding curve. The inner-loop controller is based on backstepping technique to track the AOA command generated by outer-loop controller. Barrier Lyapunov Function(BLF) design is employed to satisfy AOA requirement. Moreover, a novel auxiliary state is introduced to remove the restriction of BLF design on initial tracking errors. Dynamic Surface Control(DSC) is utilized to ease the computation burden. Rigorous stability proof is then given, and AOA is guaranteed to stay in predefined region theoretically. Simulations are conducted to verify the efficiency and superior performance of the proposed method. 展开更多
关键词 Adaptive control Angle of attack constraints Barrier Lyapunov function Hypersonic flight vehicle Phase plane design Reaching law design
Towards intelligent design optimization: Progress and challenge of design optimization theories and technologies for plastic forming 认领
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作者 Heng LI Jingchao YANG +4 位作者 Guangyao CHEN Xin LIU Zhao ZHANG Guangjun LI Wenhui LIU 《中国航空学报:英文版》 SCIE EI CAS CSCD 2021年第2期104-123,共20页
Plastic forming is one of enabling and fundamental technologies in advanced manufacturing chains. Design optimization is a critical way to improve the performance of the forming system, exploit the advantages of high ... Plastic forming is one of enabling and fundamental technologies in advanced manufacturing chains. Design optimization is a critical way to improve the performance of the forming system, exploit the advantages of high productivity, high product quality, low production cost and short time to market and develop precise, accurate, green, and intelligent(smart) plastic forming technology. However, plastic forming is quite complicated, relating to multi-physics field coupling,multi-factor influence, multi-defect constraint, and triple nonlinear, etc., and the design optimization for plastic forming involves multi-objective, multi-parameter, multi-constraint, nonlinear,high-dimensionality, non-continuity, time-varying, and uncertainty, etc. Therefore, how to achieve accurate and efficient design optimization of products, equipment, tools/dies, and processing as well as materials characterization has always been the research frontier and focus in the field of engineering and manufacturing. In recent years, with the rapid development of computing science, data science and internet of things(Io T), the theories and technologies of design optimization have attracted more and more attention, and developed rapidly in forming process. Accordingly, this paper first introduced the framework of design optimization for plastic forming. Then, focusing on the key problems of design optimization, such as numerical model and optimization algorithm,this paper summarized the research progress on the development and application of the theories and technologies about design optimization in forming process, including deterministic and uncertain optimization. Moreover, the applicability of various modeling methods and optimization algorithms was elaborated in solving the design optimization problems of plastic forming. Finally, considering the development trends of forming technology, this paper discusses some challenges of design optimization that may need to be solved and faced in forming process. 展开更多
关键词 Advanced manufacturing Design optimization Deterministic optimization(DOP) Intelligent design optimization(IDO) Plastic forming Uncertain optimization(UOP)
卡巴他赛纳米脂质载体的制备与评价 认领
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作者 罗玉莹 陈宇婷 +3 位作者 邓盛齐 张金霞 张淼 刘喜阳 《中国药学杂志》 CAS CSCD 北大核心 2021年第5期386-392,共7页
目的制备卡巴他赛纳米脂质载体(cabazitaxel nanostructured lipid carriers,Cbz-NLCs),对处方进行优化,对制剂进行质量评价,并初步考察其体外抗肿瘤活性。方法采用乳化蒸发-低温固化法制备Cbz-NLCs,响应面Box-Behnken Design筛选最优处... 目的制备卡巴他赛纳米脂质载体(cabazitaxel nanostructured lipid carriers,Cbz-NLCs),对处方进行优化,对制剂进行质量评价,并初步考察其体外抗肿瘤活性。方法采用乳化蒸发-低温固化法制备Cbz-NLCs,响应面Box-Behnken Design筛选最优处方,并制成冻干粉。采用Malvern激光粒度仪、透射电镜、差示扫描量热(differential scanning calorimeter,DSC)考察该制剂冻干粉的理化性质,采用透析法考察其体外释放规律,在低温条件下考察其初步稳定性,通过细胞毒性实验初步考察其体外抗肿瘤活性。结果按优化条件制备的Cbz-NLCs冻干粉呈球形或类球形,分布均匀,平均粒径为(186.9±3.6)nm,多分散系数(polydispersity index,PDI)为(0.213±0.003),Zeta电位为(-40.2±0.3)mV,包封率为(94.35±1.17)%,载药量为(1.11±0.32)%。DSC结果表明,卡巴他赛以无定形态存在于纳米脂质载体内。体外释放结果显示,Cbz-NLCs在8 h时释药44.48%。初步稳定性实验结果表明,Cbz-NLCs冻干粉在4℃低温条件下放置90 d内具有良好的稳定性。细胞学实验表明,与游离的卡巴他赛原料药相比,Cbz-NLCs对鼠源乳腺癌4T1细胞具有增强的细胞毒性。结论采用乳化蒸发-低温固化法制备的Cbz-NLCs粒径较小,分布均匀,包封率高,具有明显的药物缓释作用和增强的细胞毒性。 展开更多
关键词 卡巴他赛 纳米脂质载体 Box-Behnken Design 冻干粉 体外抗肿瘤
Mineral Fertilizer Use for Optimal Groundnut Production in the Sudano-Guinean and Sudanian Zones of Benin 认领
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作者 Faki O. Chabi Gustave D. Dagbenonbakin +6 位作者 Emile C. Agbangba Issa Mouftaou Augustin O. Bankolé Brice T. Oussou Léonard E. Ahoton Guillaume L. Amadji Aliou Saïdou 《土壤科学期刊(英文)》 2021年第2期72-92,共21页
Abstract This study aims to determine the optimal N, P, K, Mg and Zn rates for groundnut production on Ferric and Plintic Luvisol in the Sudano-Guinean and Sudanian zones of Benin Republic. Two years (2018 and 2019) e... Abstract This study aims to determine the optimal N, P, K, Mg and Zn rates for groundnut production on Ferric and Plintic Luvisol in the Sudano-Guinean and Sudanian zones of Benin Republic. Two years (2018 and 2019) experiment was carried out in the municipality of Ouessè in the Sudano-Guinean zone and Bembèrèkè in the Sudanian zone. The tested nutrient doses were N (0, 20 and 40 kg<span style="white-space:nowrap;">&sdot;</span>ha<sup><span style="white-space:nowrap;">&minus;</span>1</sup>), P (0, 25 and 50 kg<span style="white-space:nowrap;">&sdot;</span>ha<sup><span style="white-space:nowrap;">&minus;</span>1</sup>), K (0, 20 and 40 kg<span style="white-space:nowrap;">&sdot;</span>ha<sup><span style="white-space:nowrap;">&minus;</span>1</sup>), Mg (0, 15 and 30 kg<span style="white-space:nowrap;">&sdot;</span>ha<sup><span style="white-space:nowrap;">&minus;</span>1</sup>) and Zn (0, 4 and 8 kg<span style="white-space:nowrap;">&sdot;</span>ha<sup><span style="white-space:nowrap;">&minus;</span>1</sup>). The Box and Behnken rotating design is used to define the N, P, K, Mg and Zn rate combinations leading to 46 combinations. A completely randomized bloc design was setting up considering farmers as replication. In total, four farmers’ fields were selected. A one-way analysis of variance is carried out on yield data, using the linear mixed-effect model. Response surface analyses were used to determine the optimal doses for each N, P, K, Mg and Zn. Nodule production (6.5 times higher than the control), number of gynophores (2.8 times higher than the control) and root length (19.2 ± 0.2 cm) of groundnut plants were significantly (p = 0.0001) improved with nutrient application. The response surface analysis shows that treatments N-P-K-Mg-Zn of 16.01-20.18-6.70-5.65-2.47 (in the Sudano-Guinean zone) and 13.1-25.07-11.47-0-1.82 (in the Sudanian zone) are the optimal rates that have induced optimal yield of 2.1 t<span style="white-space:nowrap;">&sdot;</span>ha<sup><span style="white-space:nowrap;">&minus;</span>1 展开更多
关键词 Soil Fertility Response Surface Box and Behnken Design Modeling MICRONUTRIENT
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Optimal Sampling and Assay for Estimating Soil Organic Carbon 认领
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作者 Jacob V. Spertus 《土壤科学期刊(英文)》 2021年第2期93-121,共29页
The world needs around 150 Pg of negative carbon emissions to mitigate climate change. Global soils may provide a stable, sizeable reservoir to help achieve this goal by sequestering atmospheric carbon dioxide as soil... The world needs around 150 Pg of negative carbon emissions to mitigate climate change. Global soils may provide a stable, sizeable reservoir to help achieve this goal by sequestering atmospheric carbon dioxide as soil organic carbon (SOC). In turn, SOC can support healthy soils and provide a multitude of ecosystem benefits. To support SOC sequestration, researchers and policy makers must be able to precisely measure the amount of SOC in a given plot of land. SOC measurement is typically accomplished by taking soil cores selected at random from the plot under study, mixing (compositing) some of them together, and analyzing (assaying) the composited samples in a laboratory. Compositing reduces assay costs, which can be substantial. Taking samples is also costly. Given uncertainties and costs in both sampling and assay along with a desired estimation precision, there is an optimal composite size that will minimize the budget required to achieve that precision. Conversely, given a fixed budget, there is a composite size that minimizes uncertainty. In this paper, we describe and formalize sampling and assay for SOC and derive the optima for three commonly used assay methods: dry combustion in an elemental analyzer, loss-on-ignition, and mid-infrared spectroscopy. We demonstrate the utility of this approach using data from a soil survey conducted in California. We give recommendations for practice and provide software to implement our framework. 展开更多
关键词 Soil Organic Carbon COMPOSITING Carbon Sequestration Sampling Design Measurement Error STATISTICS
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Comprehensive optimization design of aerodynamic and electromagnetic scattering characteristics of serpentine nozzle 认领
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作者 Yubo HE Qingzhen YANG Xiang GAO 《中国航空学报:英文版》 SCIE EI CAS CSCD 2021年第3期118-128,共11页
Comprehensive optimization design of serpentine nozzle with trapezoidal outlet was studied to improve its aerodynamic and electromagnetic scattering performance.Serpentine nozzles with different center offsets and dif... Comprehensive optimization design of serpentine nozzle with trapezoidal outlet was studied to improve its aerodynamic and electromagnetic scattering performance.Serpentine nozzles with different center offsets and different ratios of the bases of the trapezoidal outlet were generated based on curvature control regulation.Computational Fluid Dynamics(CFD)simulations have been conducted to obtain the flow field in the nozzle,and Forward-Backward Iterative Physical Optics(FBIPO)method was applied to study the electromagnetic scattering characteristics of the nozzle.Guarantee Convergence Particle Swarm Optimization(GCPSO)algorithm based on Radial Basis Function(RBF)neural network was used to optimize the geometry of the nozzle in consideration of its aerodynamic and electromagnetic scattering characteristics.The results show that the GCPSO method based on RBF can be used to optimize the aerodynamic characteristics of the internal flow and the scattering characteristics of the cavity of the serpentine nozzle with irregular outlet.The optimized model has a higher center offset and a lower ratio of the bases of the trapezoidal outlet after optimization compared to the original model.The optimized model leads to a slight change in aerodynamic performance,with a total pressure recovery coefficient increase of 0.31%and a discharge coefficient increase of 0.41%.In addition,the Radar Cross Section(RCS)decreases also by around 83.33%and the overall performance is significantly improved,with a decrease of the optimized objective function by around 38.74%. 展开更多
关键词 Forward-Backward Iterative Physical Optics(FBIPO) Guarantee Convergence Particle Swarm Optimization(GCPSO) Nozzle design Optimization design Radar Cross Section(RCS) Serpentine nozzle
Shake table experimental study of cable-stayed bridges with two different design strategies of H-shaped towers 认领
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作者 Xu Yan Cui Cunyu +1 位作者 Zeng Zeng Zeng Shijie 《地震工程与工程振动:英文版》 SCIE EI CSCD 2021年第2期483-493,共11页
As one of the main load-carrying components of cable-stayed bridges,bridge towers are typically required to remain elastic even when subjected to severe ground motions with a 2%-3%probability of exceedance in 50 years... As one of the main load-carrying components of cable-stayed bridges,bridge towers are typically required to remain elastic even when subjected to severe ground motions with a 2%-3%probability of exceedance in 50 years.To fulfill this special requirement imposed by current seismic design codes,reinforcement ratios in the bridge towers have to be kept significantly higher than if limited ductility behavior of the tower is allowed.In addition,since the foundation capacity is closely related to the moment and shear capacities of the bridge tower,a large increase in bridge construction cost for elastically designed cable-stayed bridge is inevitable.To further investigate the possibility of limited ductility bridge tower design strategies,a new 1/20-scale cable-stayed bridge model with H-shaped bridge towers designed according to strong strut-weak tower column design was tested.The shake table experimental results are compared with a previous strong tower column-weak strut designed full bridge model.A comparison of the results show that ductility design with plastic hinges located on tower columns,i.e.,strong strut-weak tower column design,is another effective seismic design strategy that results in only small residual displacement at the top of the tower column,even under very severe earthquake excitations. 展开更多
关键词 cable-stayed bridge shake table experiment limited ductility design H-shaped bridge tower seismic design
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185/60R14 82H TAXIPLUS出租车专用轮胎的设计 认领
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作者 李海艳 陈健 +3 位作者 郭志刚 张聪 路丹丹 秦怡如 《橡塑技术与装备》 CAS 2021年第1期43-46,共4页
本文介绍了185/60R1482H规格TAXIPLUS出租车专用轮胎的设计,外轮廓方面,轮胎的设计外直径575 mm,充气断面宽194 mm,轮胎的行驶面宽138 mm,设计行驶面弧高度6.1 mm,胎圈着合直径取值350.1 mm,轮胎的胎圈着合宽度153 mm,轮胎的断面水平轴... 本文介绍了185/60R1482H规格TAXIPLUS出租车专用轮胎的设计,外轮廓方面,轮胎的设计外直径575 mm,充气断面宽194 mm,轮胎的行驶面宽138 mm,设计行驶面弧高度6.1 mm,胎圈着合直径取值350.1 mm,轮胎的胎圈着合宽度153 mm,轮胎的断面水平轴位置取值0.9843;轮胎的胎面花纹设计分为,长型花纹(M型、L型)与短型花纹(S型),3种花纹为交替变节距呈现,花纹深度8.5 mm,花纹饱和度69.35%[2~3]。轮胎的施工设计方面:胎面挤出部件位全分层设计,可更好的区分胶种,功能性更强,胎侧挤出部件为双复合设计,冠带层的1#、2#带束层材料使用3×0.30HT钢丝帘线,胎圈部位的钢丝圈为斜六角形结构,更好的保证了成品断面钢丝圈部位,切割后的近圆形;胎胚的成型使用的设备是萨驰一次法成型机,胎胚的硫化使用的设备是韩国东和液压硫化机,硫化工艺为氮气硫化。生产的成品轮胎的外缘尺寸、强度性能和耐久性能等均满足国家标准要求。 展开更多
关键词 185/60R14 出租车专用轮胎 设计 施工设计
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对于中国传统服装“开裆裤”的调查与研究——应用Anonymous Design为卧床癌病患者设计的下装研究 认领
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作者 徐玉(翻译) 鸟丸知子(翻译) 《艺术设计研究》 2021年第2期36-43,共8页
本文是日本学术振兴会科学研究费基金项目中以“应用Anonymous Design来为卧床癌症患者设计的下装研究”阶段性成果。在这项研究中,笔者于2019年2月对中国开裆裤进行了实物调研。开裆裤通常被认为是幼儿使用的、裆部有开口的裤子,其原... 本文是日本学术振兴会科学研究费基金项目中以“应用Anonymous Design来为卧床癌症患者设计的下装研究”阶段性成果。在这项研究中,笔者于2019年2月对中国开裆裤进行了实物调研。开裆裤通常被认为是幼儿使用的、裆部有开口的裤子,其原型具有很悠久的历史,有不同的样式。关于Anonymous Design,没有统一的定义,笔者在这项研究中将其界定为“没有特定的作者或设计师设计过的物品。典型的例子如传统服装,它是前人的创造力与智慧的结果、产物、或行为。虽质朴但其易于使用的功能性得以长期被沿用,现代人认为“理所当然”的事物原点”。开裆裤完全符合笔者定义的Anonymous Design。本文主要论述笔者在中国进行的开裆裤调研成果,以及整理归纳开裆裤的结构和款式,并提出开裆裤的设计具有“卧床癌症患者使用的下装”所需的应用可能性。 展开更多
关键词 Anonymous Design 病衣 下装 开裆裤
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基于期刊文献的近五年中国设计学研究综述 认领
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作者 陈月华 彭慕星 《工业工程设计》 2021年第1期11-18,59,共9页
2011年设计学正式成为一级学科,在这十年之间,中国设计学研究飞速发展,但仍存在学科界定不明确、研究对象范式混乱等问题。本文筛选近五年内国内期刊文献,对国内设计史、设计理论及设计批评三个大方向的设计学研究进行系统梳理,综述相... 2011年设计学正式成为一级学科,在这十年之间,中国设计学研究飞速发展,但仍存在学科界定不明确、研究对象范式混乱等问题。本文筛选近五年内国内期刊文献,对国内设计史、设计理论及设计批评三个大方向的设计学研究进行系统梳理,综述相关研究成果并对未来中国设计学研究提出建议与展望。 展开更多
关键词 设计学 设计理论 研究综述
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A Decomposition of a Complete Graph with a Hole 认领
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作者 Roxanne Back Alejandra Brewer Castano +1 位作者 Rachel Galindo Jessica Finocchiaro 《离散数学期刊(英文)》 2021年第1期1-12,共12页
<div style="text-align:justify;"> <span style="font-family:Verdana;">In the field of design theory, the most well-known design is a Steiner Triple System. In general, a G-design on H is... <div style="text-align:justify;"> <span style="font-family:Verdana;">In the field of design theory, the most well-known design is a Steiner Triple System. In general, a G-design on H is an edge-disjoint decomposition of H into isomorphic copies of G. In a Steiner Triple system, a complete graph is decomposed into triangles. In this paper we let H be a complete graph with a hole and G be a complete graph on four vertices minus one edge, also referred to as a <img alt="" src="Edit_e69ee166-4bbc-48f5-8ba1-b446e7d3738c.png" /> . A complete graph with a hole, <img alt="" src="Edit_558c249b-55e8-4f3b-a043-e36d001c4250.png" />, consists of a complete graph on <em>d</em> vertices, <img alt="" src="Edit_cb1772f7-837c-4aea-b4a6-cb38565f5a8b.png" />, and a set of independent vertices of size<em> v, V,</em> where each vertex in <em>V</em> is adjacent to each vertex in <img alt="" src="Edit_cb1772f7-837c-4aea-b4a6-cb38565f5a8b.png" />. When <em>d</em> is even, we give two constructions for the decomposition of a complete graph with a hole into copies of <img alt="" src="Edit_e69ee166-4bbc-48f5-8ba1-b446e7d3738c.png" /> : the Alpha-Delta Construction, and the Alpha-Beta-Delta Construction. By restricting <em>d</em> and <em>v</em> so that <img alt="" src="Edit_6bb9e3b4-1769-4b28-bf89-bc97c47c637e.png" /><span style="white-space:nowrap;"> </span>, we are able to resolve both of these cases for a subset of <img alt="" src="Edit_558c249b-55e8-4f3b-a043-e36d001c4250.png" />using difference methods and 1-factors.</span> </div> 展开更多
关键词 Graph Decomposition Combinatorial Design Complete Graph with a Hole
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小学数学教学中的有效练习设计与开展 认领
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作者 张会民 《天津教育》 2021年第10期100-102,共3页
数学是一门逻辑性非常强的学科,小学数学课堂是为了帮助各位同学打下良好的学习基础,因此在教学过程中,教师要根据各位同学的实际情况制定教学计划,对教学方式进行创新,为学生营造良好的数学学习氛围,本文针对小学数学课堂有效练习设计... 数学是一门逻辑性非常强的学科,小学数学课堂是为了帮助各位同学打下良好的学习基础,因此在教学过程中,教师要根据各位同学的实际情况制定教学计划,对教学方式进行创新,为学生营造良好的数学学习氛围,本文针对小学数学课堂有效练习设计进行了阐述,以期可以提高小学数学课堂教学质量,加深学生对所学知识的理解。 展开更多
关键词 小学数学课堂 有效练习 设计
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An economic analysis of twenty light olefin production pathways 认领
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作者 Zhitong Zhao Jingyang Jiang Feng Wang 《能源化学:英文版》 SCIE EI CAS CSCD 2021年第5期193-202,共10页
A comprehensive economic analysis of twenty light olefin production pathways has been performed,covering current and promising processes from fossil(petroleum,coal and natural gas)and renewable resources(biomass and C... A comprehensive economic analysis of twenty light olefin production pathways has been performed,covering current and promising processes from fossil(petroleum,coal and natural gas)and renewable resources(biomass and CO2).Taking steam cracking of naphtha as the benchmark,this study gives an economic perspective and points out the bottleneck in different olefin production pathways.The assessment indicates that nearly all renewable pathways are economically unattractive currently and the raw material cost accounts for dominant contribution in most pathways,especially in the oil-,natural gas-and CO2-derived pathways.For the ways of methanol-to-olefins and methanol-to-propylene,fossil pathways are cost-competitive according to the date of current Chinese market prices.However,the price of feedstock hydrogen needs to be lowered by 55%to fill the cost gap between CO2-derived pathways and the benchmark.For the ways of oxidative coupling of methane and Fischer-Tropsch synthesis to olefins,fossil pathways enable cost-competitive processes by feedstock price fall,but further process improvement is required to approach benchmark in renewable pathways.Conditionally,a decrease in ethanol price by45%can make ethanol dehydration pathway profitable.In addition,costs can reduce by 4%-23%in different pathways as the production scales expand from 100 to 1000 kt/a,resulting in a change from high cost to economic profit for some of the pathways.The results quantify the need for improvements on feedstock price,scale size and process improvement to achieve competitive production costs. 展开更多
关键词 ETHYLENE PROPYLENE OLEFIN TECHNO-ECONOMIC Conceptual design
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基于BIM技术的铁路路基设计应用分析 认领
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作者 刘涵 《工程建设与设计》 2021年第7期121-123,共3页
分析BIM技术和铁路路基设计,结合具体案例对BIM技术在皱路路基过程中的设计流程、软件应用、建模、出图、具体运用等进行研究。研究结果表明,基于BIM技术的铁路路基设计具有可行性,值得推广使用。
关键词 BIM技术 铁路 路基 设计 应用
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基于ETL技术的医院质控数据库系统设计与实现 认领
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作者 崔金广 窦一峰 +1 位作者 蒙文涛 吴秀春 《医学信息》 2021年第4期16-21,共6页
针对公立医院三级绩效考核数据采集分散、数据统计公式和标准不规范、内容反馈和呈现不直观等问题,本文构建了基于数据仓库(ETL)技术的医院质控数据库系统,主要包括时间维度与科室维度下的数据字典、指标分类、数据录入、报告展示、对... 针对公立医院三级绩效考核数据采集分散、数据统计公式和标准不规范、内容反馈和呈现不直观等问题,本文构建了基于数据仓库(ETL)技术的医院质控数据库系统,主要包括时间维度与科室维度下的数据字典、指标分类、数据录入、报告展示、对比输出等内容。依托大数据分析,通过Kettle分别由HIS、LIS、PACS、EMR、卫生统计、OA等信息系统提取数据,将其加工、整理后存储到质控数据库,并开发设计B/S架构的医院质控数据库系统,对质控数据进行统一管理。最终实现及时准确的提取、加工、整理质控指标数据的目的,旨在为院领导决策、职能处室和临床科室提供准确有效的数据支持。 展开更多
关键词 医院质控数据库 医疗质量 质控指标 设计
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非对称变截面斜塔斜拉桥主桥结构设计与施工 认领
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作者 饶宗润 李明 《科技创新与应用》 2021年第1期114-116,共3页
非对称变截面斜塔斜拉桥由于技术经济上的合理性和美学上的优越性,随着公路建设的发展,将成为小型斜拉桥建设的主流,适用于中、西部山区建设,市场潜力巨大。文章结合工程实例,对斜拉桥的主塔、钢箱梁、钢混结合段、斜拉索等结构的设计... 非对称变截面斜塔斜拉桥由于技术经济上的合理性和美学上的优越性,随着公路建设的发展,将成为小型斜拉桥建设的主流,适用于中、西部山区建设,市场潜力巨大。文章结合工程实例,对斜拉桥的主塔、钢箱梁、钢混结合段、斜拉索等结构的设计以及相应施工技术进行探讨,可为类似工程提供参考和借鉴。 展开更多
关键词 斜塔 斜拉桥 设计 钢箱梁
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