A bi-objective mathematical model toward dynamic cell formation considering labor utilization

This paper addresses dynamic cell formation problem (DCFP) via a new bi-objective mathematical formulation. Although literature body of DCFP includes a vast number of research instances, human-related issues are mostly neglected as an important aspect of DCFP in the corresponding literature. In this paper, the first objective function seeks to minimize relevant costs of the problem including machine procurement and relocation costs, machine variable cost, inter-cell movement and intra-cell movement costs, overtime cost and labor shifting cost between cells, while labor utilization of the modeled DCFP is maximized through the second objective function. Due to NP-hardness of DCFP, an ant colony optimization (ACO) meta-heuristic is developed for the first time in the literature to tackle the problem. Also, authors enhance diversification of the developed algorithm is enhanced by hybridization of the proposed ACO algorithm with a genetic one. Finally, some numerical samples are generated randomly to validate the proposed model by which strengths of the developed algorithm is shown.     

基于社会性科学议题的化学微项目学习*——以“物质的性质与转化”单元复习为例

在化学课堂中开展社会性科学议题的教学能够发展学生的社会参与意识,结合微项目学习模式,从课堂教学角度出发,构建选定项目、启动项目、实施项目、交流成果等4个教学流程,确立实施教学的核心问题,设计了鲁科版高一化学“物质的性质与转化单元复习课”,进行了基于社会性科学议题的化学微项目学习的实践教学,结合实践的基本情况提出4点反思。     

Public debates driven by incomplete scientific data: The cases of evolution theory, global warming and H1N1 pandemic influenza

Public debates driven by incomplete scientific data where nobody can claim absolute certainty, due to the current state of scientific knowledge, are studied. The cases of evolution theory, global warming and H1N1 pandemic influenza are investigated. The first two are of controversial impact while the third is more neutral and resolved. To adopt a cautious balanced attitude based on clear but inconclusive data appears to be a lose-out strategy. In contrast overstating arguments with incorrect claims which cannot be scientifically refuted appears to be necessary but not sufficient to eventually win a public debate. The underlying key mechanisms of these puzzling and unfortunate conclusions are identified using the Galam sequential probabilistic model of opinion dynamics (Galam, 2002 [4], Galam, 2005 [18], Galam and Jacobs, 2007 [19]). It reveals that the existence of inflexible agents and their respective proportions are the instrumental parameters to determine the faith of incomplete scientific data in public debates. Acting on one’s own inflexible proportion modifies the topology of the flow diagram, which in turn can make irrelevant initial supports. On the contrary focusing on open-minded agents may be useless given some topologies. When the evidence is not as strong as claimed, the inflexibles rather than the data are found to drive the opinion of the population. The results shed a new but disturbing light on designing adequate strategies to win a public debate.     

论证“是否应该停止使用氮肥”社会性科学议题教学——氮及其化合物的复习

“氮及其化合物”复习教学中,通过社会性科学议题“是否应该停止使用氮肥”,在真实复杂的两难问题情境中,使学生基于物质类别和元素价态视角分析、设计氮肥的制备、使用以及减少其对环境影响中涉及的含氮物质的转化,提高学生自主应用氮元素“价-类”二维图综合分析、解决真实问题的能力,促进证据推理与模型认知、科学探究与创新意识、科学态度与社会责任等多维度化学学科核心素养的融合发展。经过多轮教学改进,结合教学效果抽提出以下教学策略：课上课下统筹安排,合理设置任务,提高学生参与议题的兴趣,促使学生全身心投入对议题的探讨;聚焦真实问题解决,将议题的探讨过程与关键能力持续进阶紧密结合并相互促进;让学生经历“做真事、真做事、真反思、真发展”的完整过程。     

雅砻江锦屏一级水电站坝址区实测地应力与重大工程地质问题分析

本文对雅砻江锦屏一级水电站坝址区Ⅱ1-Ⅱ1及其前后剖面实测地应力进行了系统整理分析。分析结果表明:在相同的水平和垂直埋深条件下左岸坡角应力大小较右岸坡角小,这主要是由边坡岩体结构确定的;左岸导流洞开挖过程中在应力大小较右岸低的情况下出现坍塌工程地质问题也与左岸边坡岩体结构有关,而非岩爆等诱发。另外对左岸岩体深部裂缝在已有研究成果的基础上从应力集中、能量积累角度初步提出了新的边坡变形破坏方式,并从岩体结构和地应力大小方面对锦屏一级水电站工程建设过程中左、右岸应注意的工程地质问题提出了初步建议。     

基于社会性科学议题促进核心素养发展的元素化合物教学*——以“论证重雾霾天气‘汽车限行’的合理性”为例

在“氮及其化合物”教学中,利用社会性科学议题“论证重雾霾天气‘汽车限行’的合理性”,通过直面议题激发原始想法、探讨汽车尾气与雾霾是否存在关系、探讨汽车尾气是不是导致雾霾的主要原因、面对议题的科学决策的具体教学环节,促进学生掌握氮及其化合物的主要性质,建立从物质类别、元素价态视角研究物质性质及转化的思路方法,促进多个维度核心素养的融合发展。经过多轮次教学改进,结合教学实践过程及其教学效果抽提出真实情境的创设、驱动性问题的设计、课前、课上和课后3个阶段统筹安排等教学策略。     

Research, practice, uncertainty and responsibility

Three issues concerning the relationship between research and practice are addressed. (1) A certain ‘prototype mathematics classroom’ seems to dominate the research field, which in many cases seems selective with respect to what practices to address. I suggest challenging the dominance of the discourse created around the prototype mathematics classroom. (2) I find it important to broaden the school-centred discourse on mathematics education and to address the very different out-of-school practices that include mathematics. Many of these practices are relevant for interpreting what is taking place in a school context. That brings us to (3) socio-political issues of mathematics education. When the different school-sites for learning mathematics as well as the many different practices that include mathematics are related, we enter the socio-political dimension of mathematics education.On the one hand we must consider questions like: Could socio-political discrimination be acted out through mathematics education? Could mathematics education exercise a regimentation and disciplining of students? Could it include discrimination in terms of language? Could it include sexism and racism? On the other hand: Could mathematics education bring about competencies which can be described as empowering, and as supporting the development of mathematical literary or a ‘mathemacy’, important for the development of critical citizenship?However, there is no hope for identifying a one-way route to mathemacy. More generally: There is no simple way of identifying the socio-political functions of mathematics education. Mathematics education has to face uncertainty, and this challenge brings us to the notion of responsibility.     

城市“热岛”效应对土体工程性质的影响及其关键科学问题

随着全球气候变暖、城市化进程加快,世界各地大城市的“热岛”效应及其带来的各种环境和生态问题越来越严重。本文从地质环境保护的角度,分析了城市“热岛”效应的成因、特点及其对地质环境的影响,重点讨论了城市“热岛”效应环境中土体工程性质的变化及其带来的各种灾害效应,在此基础上,凝练出了4个关键科学问题,即城市“热岛”效应环境中土体温度场变化规律、土体中水分迁移规律、土体工程性质变化规律以及土体地质灾害效应,并对它们的具体研究内容进行了详细的分析。论文的分析成果对于掌握城市“热岛”效应对土体工程性质的影响,保护城市地质环境和防灾减灾,实现城市的可持续发展具有重要的理论和现实意义。
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固体破坏理论的若干问题

本文列举和初步探讨了位于当代固体破坏理论的前沿上的十五个问题。它们包括：固体破坏理论的封闭、宏微观非线性力学、尺度效应、多层次计算、细微观实验力学技术、断裂过程区的描述、异质体的强度与韧性、材料的多层次抗破坏设计、高速破坏过程、非均匀介质的动态断裂与前兆、疲劳的起源、破坏元技术、内损伤破坏与微结构形貌演化失稳的识别、材料的微结构演化、电致失效力学。     

一门崭新的交叉科学:网络科学(下篇)

在上篇综述里,我们评述了网络科学的发展简史,基本概念和网络分类,以及国内外迄今提出的复杂网络的主要理论模型及其拓扑特性。着重总结了我们"一院二校"开展的国家自然科学基金重点项目的研究进展,上篇的研究成果主要涉及加权网络模型、和谐统一的混合模型和量子信息网络模型及其纳米网络,简单说,我们探索了从宏观网络到微观网络的不同层次的若干特点和结果。在下篇综述里,我们将系统概述5个重要课题的研究进展,从第7章到第11章,课题内容包括:复杂网络的动力学完全同步与网络的拓扑结构之间的关系;网络拓扑结构的对称性破缺导致动力学部分同步;给出判断给定网络部分同步斑图稳定性的方法和一般判据,讨论了由网络的多种拓扑对称导致的部分同步斑图的竞争和选择问题以及李指数谱的简并性质。进一步,分别以具有小世界和无标度拓扑结构的束流输运网络为典型的"混沌复杂网络",提出了实现束晕-混沌的同步和控制的若干方法,特别是实现分区网络的多目标的同步控制问题。同时,基于Vicsek模型和Boid模型,研究了生物体集群动态网络的拓扑结构和动力学方程,提出复杂多智能体网络的协调控制策略。另外,从复杂网络的不同拓扑结构对合作涌现和资源分配的作用角度,评述了三个主要的博弈模型—少数者博弈、囚徒困境和雪堆博弈,研究了复杂网络的群聚系数和网络异质性等结构特性对个体的博弈行为的重要影响。最后第12章,我们简介其它课题的进展,讨论了网络科学面临的挑战,并展望了其应用与发展前景。