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关键词： 材料科学与工程基础   计算机模拟   创新创业   多元化教学探索  

摘要： “材料科学与工程基础”作为高等院校材料类学科课程体系中的专业基础课程,知识体系涉及广,传统教学模式难以取得良好教学效果。课程教师以计算机模拟引导,结合创新创业能力培养目标为导向,从教学内容、教学方式、考核方法和科教融合四个方面开展了课程多元化教学探索。实践证明在课堂教学中引入计算机模拟手段不仅有效结合了科研资源和传统教学手段,而且可以激发学生学习兴趣,提高课堂效能,让学生更好地掌握材料科学与工程的基础知识。

关键词： 计算机   设计   交叉融合教学  

摘要： 随着信息化时代的发展,计算机科学与设计学科的交叉融合越来越受到关注,学科融合教育既有利于计算机专业学生创新思维的培养,也拓宽了设计专业学生的就业面。在此有必要从一般意义上分析计算机学科、设计学科以及二者学科交叉融合教学的现状和问题。在此基础上,探索新时期计算机与设计交叉融合教学创新人才培养方法,促进学科融合教育实践。

关键词： 池塘流水槽循环水养殖   黑鲷   养殖模式   血清生化指标   抗氧化  

摘要： 比较池塘流水槽养殖和传统池塘养殖模式下黑鲷幼鱼(初始平均体质量为5.29 g)生长、血清生化指标及抗氧化能力。60 d的养殖结果表明,流水槽养殖组黑鲷增质量率、特定生长率均显著高于池塘养殖组(P<0.05);血清中谷草转氨酶活性、谷丙转氨酶活性、总蛋白含量、总胆固醇含量、皮质醇含量、溶菌酶含量和超氧化物歧化酶在处理组之间无显著性差异;流水槽养殖组血清中碱性磷酸酶活性显著高于池塘养殖组,而血糖和甘油三酯含量正好相反;流水槽养殖组肝脏谷胱甘肽过氧化物酶活性、总超氧化物歧化酶活性、总抗氧化能力均显著高于池塘养殖组,而过氧化氢酶活性和丙二醛含量无显著性差异。总之,在本试验条件下,池塘流水槽养殖模式能提高黑鲷(体质量为5~37 g)的生长和机体免疫力,降低肌肉脂肪含量。

关键词： Feature extraction   Prediction algorithms   Markov processes   Benchmark testing   Bayes methods   Computer science   Cybernetics   Bayesian network (BN)   causal feature selection   Markov boundary (MB)   PCMasking  

摘要： Causal feature selection has achieved much attention in recent years, which discovers a Markov boundary (MB) of the class attribute. The MB of the class attribute implies local causal relations between the class attribute and the features, thus leading to more interpretable and robust prediction models than the features selected by the traditional feature selection algorithms. Many causal feature selection methods have been proposed, and almost all of them employ conditional independence (CI) tests to identify MBs. However, many datasets from real-world applications may suffer from incorrect CI tests due to noise or small-sized samples, resulting in lower MB discovery accuracy for these existing algorithms. To tackle this issue, in this article, we first introduce a new concept of PCMasking to explain a type of incorrect CI tests in the MB discovery, then propose a cross-check and complement MB discovery (CCMB) algorithm to repair this type of incorrect CI tests for accurate MB discovery. To improve the efficiency of CCMB, we further design a pipeline machine-based CCMB (PM-CCMB) algorithm. Using benchmark Bayesian network datasets, the experiments demonstrate that both CCMB and PM-CCMB achieve significant improvements on the MB discovery accuracy compared with the existing methods, and PM-CCMB further improves the computational efficiency. The empirical study in the real-world datasets validates the effectiveness of CCMB and PM-CCMB against the state-of-the-art causal and traditional feature selection algorithms.

摘要： Mensch-Computer-Interaktion (MCI) beschäftigt sich mit Fragen rund um die benutzer- und kontextegerechte Gestaltung von IT-Systemen. Ohne MCI ist die vielbeschworene digitale Transformation nicht möglich, da Systeme, die nicht benutzbar (gebrauchstauglich) sind, für ihre Nutzer wertlos oder sogar gefährlich sind – erst Nutzbarkeit schafft Nutzen! In diesem Beitrag sammeln wir einige Beispiele dafür, wo und wie MCI in der Entwicklung zukünftiger IT-Systeme relevant ist – von nutzerzentrierter künstlicher Intelligenz über benutzbare Sicherheit, cyberphysische Systeme und digital Arbeit hin zu Augmented Reality und Virtual Reality.

关键词： Polyculture   Stocking density   Penaeus monodon   Gracilaria tenuistipitata   Rhodophyta   Water quality   Shrimp performance   Vibrio parahaemolyticus  

摘要： The integration of seaweeds (extractive, low-footprint species) into aquaculture systems has been considered an alternative approach for the sustainable development of the shrimp industry, which aims to expand in an environmentally friendly way. Two consecutive experiments were conducted to evaluate the effects of integrating various densities of black tiger shrimpPenaeus monodonpost-larvae (PL) and red seaweedGracilaria tenuistipitataon water quality and shrimp performance in the nursery phase. The first experiment involved a 3 x 4 factorial design with three levels of shrimp density (1000;2000 and 3000 PL m(-3)) and four levels of red seaweed density (0, 1.0, 1.5 and 2.0 kg m(-3)) randomly allocated in triplicate tanks for 30 days. Shrimp PL (with a mean weight of 0.012 +/- 0.002 g and length of 1.12 +/- 0.09 cm) and red seaweed were reared in 150 L tanks at a salinity of 15 g L-1. Significant synergistic effects between shrimp and seaweed densities were observed for the NO(3)(-)total nitrogen (TN) and PO(4)(3-)contents, as well as for the survival (p< 0.05) and production of shrimp (p< 0.01). The integration of shrimp and red seaweed significantly decreased the concentrations of nitrogen and phosphorus in the rearing tanks and greatly enhanced the survival and growth rate of shrimp. In particular, increased stocking density resulted in poorer growth performance but enhanced production. Applying stocking densities of 1000 and 2000 PL m(-3)obtained larger shrimp size, while a density of 3000 PL m(-3)achieved the highest production output in the integrated system. In the second experiment, which followed the 30-day growth trial, shrimp quality was assessed via an immersion challenge test using pathogenicVibrio parahaemolyticus(a concentration of 2 x 10(8)CFU mL(-1)) on the shrimp groups previously stocked at a density of 3000 PL m(-3)and integrated with different quantities of seaweed. After 14 days of challenge, the cumulative mortality in the monoculture system av

关键词： Schedules   Protocols   Software   Routing   IEEE transactions   Computer science   Heuristic algorithms   Software defined networks   relaxed loop freedom   network updates  

摘要： We consider a fundamental update problem of avoiding forwarding loops based on the node-ordering protocol in Software Defined Networks (SDNs). Due to the distributed data plane, forwarding loops may occur during the updates and influence the network performance. The node-ordering protocol can avoid such forwarding loops by controlling the update orders of the switches and does not consume extra flow table space overhead. However, an Omega(n) lower bound on the number of rounds required by any algorithm using this protocol with loop-free constraint has been proved, where n is the number of switches in the network. To accelerate the updates, a weaker notion of loop-freedom - relaxed loop-freedom - has been introduced. Despite that, the theoretical bound of the node-ordering protocol with relaxed loop-free constraint remains unknown yet. In this article, we solve a long-standing open problem: how to derive omega(1)-round lower bound or to show that O(1)-round schedules always exist for the relaxed loop-free update problem. Specifically, we prove that any algorithm needs Omega(log n) rounds to guarantee relaxed loop freedom in the worst case. In addition, we develop a fast relaxed loop-free update algorithm named Savitar that touches the tight lower bound. For any update instance, Savitar can use at most 2left perpendicularlog(2) nright perpendicular - 1 rounds to schedule relaxed loop-free updates. Extensive experiments on Mininet using a Floodlight controller show that Savitar can significantly decrease the update time, achieve near optimal performance and save over 30% of the rounds compared with the state of the art.