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41.
化学产品工程作为化学工程学科的一个新方向或化学工程学科的新范式已提出很多年,但学术界对其学科内涵理解不一。本文对化学产品工程的学科内涵进行了分析和探讨,认为其核心是通过过程和设备对产品的纳微结构和复杂大分子结构进行调控;化学产品工程仍隶属过程工程,是面向高附加值产品、实现产品结构可控、定向、高效制备的过程工程。通过与传统的以满足市场需求和提高生产效率为目标的过程开发和放大的化学工程研究类比,提出了化学产品工程的主要研究内容,并讨论了其研究的方法论问题,以推动相关的基础研究工作。 相似文献
42.
Qinghai Miao Wenbo Zheng Yisheng Lv Min Huang Wenwen Ding Fei-Yue Wang 《IEEE/CAA Journal of Automatica Sinica》2023,10(4):877-897
From AlphaGo to ChatGPT,the field of AI has launched a series of remarkable achievements in recent years.Analyzing,comparing,and summarizing these achievements at the paradigm level is important for future AI innovation,but has not received sufficient attention.In this paper,we give an overview and perspective on machine learning paradigms.First,we propose a paradigm taxonomy with three levels and seven dimensions from a knowledge perspective.Accordingly,we give an overview on three basic and tw... 相似文献
43.
Optimal distributed power allocation for a new spectrum sharing paradigm in cognitive radio networks
The problem of power allocation in cognitive radio networks plays an important role to improve the efficiency of spectrum utilization. However, most of previous works focus on the power allocation for secondary users in spectrum sharing overlay or spectrum sharing underlay, which needs to frequently handoff between the idle spectrum bands or considers the interference constraints in all spectrum bands respectively. In order to reduce the handoff and fully utilize the spectrum resource, we propose a new spectrum sharing paradigm which not only can just need to adjust the transmit power in spectrum bands instead of frequently handoff between idle spectrum bands, but can fully utilize the spectrum resource as we only consider the interference power constraints in active spectrum bands rather than in all spectrum bands. Then based on this new spectrum sharing paradigm and the constraint conditions, we study the distributed power allocation for secondary users and formulate the optimization problem as a non-cooperative game problem, after that the variational inequality approach is used to solve this game problem and a Nash equilibria solution is got, finally simulation results are illustrated to demonstrate the performance of the proposed scheme. 相似文献
44.
In the stop-signal paradigm, fast responses are harder to inhibit than slow responses, so subjects must balance speed in the go task with successful stopping in the stop task. In theory, subjects achieve this balance by adjusting response thresholds for the go task, making proactive adjustments in response to instructions that indicate that relevant stop signals are likely to occur. The 5 experiments reported here tested this theoretical claim, presenting cues that indicated whether or not stop signals were relevant for the next few trials. Subjects made proactive response-strategy adjustments in each experiment: Diffusion-model fits showed that response threshold increased when participants expected stop signals to occur, slowing go responses and increasing accuracy. Furthermore, the results show that subjects can make proactive response-strategy adjustments on a trial-by-trial basis, suggesting a flexible cognitive system that can proactively adjust itself in changing environments. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
Alvin G. Stern 《International Journal of Hydrogen Energy》2018,43(9):4244-4255
We analyze the feasibility of a novel, hydrogen fuel cell electric generator to provide power with zero noise and emissions for myriad ground based applications. The hydrogen fuel cell electric generator utilizes a novel, scalable apparatus that safely generates hydrogen (H2) on demand according to a novel method, using a controlled chemical reaction between water (H2O) and sodium (Na) metal that yields hydrogen gas of sufficient purity for direct use in fuel cells without risk of contaminating sensitive catalysts. The sodium hydroxide (NaOH) byproduct of the hydrogen producing reaction, is collected within the apparatus for later reprocessing by electrolysis, to recover the Na reactant. The detailed analysis shows that the novel, hydrogen fuel cell electric generator will be capable of meeting the clean power requirements for residential and commercial buildings including single family homes and light commercial establishments under a wide range of geographic and climatic conditions. 相似文献
46.
可持续水资源管理量化研究的关键问题 总被引:1,自引:1,他引:0
“可持续水资源管理”是当今世界水问题研究的热点之一 [1 ] 。目前 ,国际上对可持续水资源管理的研究还处在对量化研究的积极探索阶段。由于可持续水资源管理量化研究涉及的内容广泛、许多基础问题还没有完全解决 ,使得可持续水资源管理量化研究方法还很不成熟。本文在总结前期研究成果的基础上 ,探讨了目前研究的几个关键问题 ,即准则问题、指标体系问题、基础模型问题、量化方法问题 相似文献
47.
在邓宁的折衷范式下阐述了我国商业银行进行对外直接投资所具有的所有权优势、区位优势和内部化优势。随着我国经济的发展和非金融企业对外投资的增加,其对外直接投资规模会不断扩大,但政府需为其创造一个有利的环境,并在折衷范式框架下具体分析了面临的问题和可采取的对策。 相似文献
48.
49.
Abstract. In this journal, Chen and Hirschheim have provided a historical analysis of positivist and interpretivist research paradigms and methodologies in the 10 years following the much cited work of Orlikowski and Baroudi. In this paper, we investigate the mysterious case of the missing paradigm – that of the critical approach to information systems (IS) research. We take Chen and Hirschheim's survey as our starting point and aim to fill the gap left by the absence of the critical paradigm in their analysis and make some criticisms of their method. Recent years have seen the growth of IS research that consciously adopts a critical perspective. This paper charts the development of critical IS research over the period of 1991–2001, adding some comments on more recent developments. We conclude by critically reflecting on the current development of critical research in the field of IS. 相似文献
50.
Facing the scale, heterogeneity and dynamics of the global computing platform emerging on top of the Internet, autonomic computing has been raised recently as one of the top challenges of computer science research. Such a paradigm calls for alternative programming abstractions, able to express autonomic behaviours. In this quest, nature-inspired analogies regained a lot of interest. More specifically, the chemical programming paradigm, which envisions a program’s execution as a succession of reactions between molecules representing data to produce a result, has been shown to provide some adequate abstractions for the high-level specification of autonomic systems. 相似文献