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Models for Location Inventory Routing Problem of Cold Chain Logistics with NSGA-Ⅱ Algorithm 被引量:1
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作者 郑建国 李康 伍大清 《Journal of Donghua University(English Edition)》 EI CAS 2017年第4期533-539,共7页
In this paper,a novel location inventory routing(LIR)model is proposed to solve cold chain logistics network problem under uncertain demand environment. The goal of the developed model is to optimize costs of location... In this paper,a novel location inventory routing(LIR)model is proposed to solve cold chain logistics network problem under uncertain demand environment. The goal of the developed model is to optimize costs of location,inventory and transportation.Due to the complex of LIR problem( LIRP), a multi-objective genetic algorithm(GA), non-dominated sorting in genetic algorithm Ⅱ( NSGA-Ⅱ) has been introduced. Its performance is tested over a real case for the proposed problems. Results indicate that NSGA-Ⅱ provides a competitive performance than GA,which demonstrates that the proposed model and multi-objective GA are considerably efficient to solve the problem. 展开更多
关键词 cold chain logistics MULTI-OBJECTIVE location inventory routing problem(LIRP) non-dominated sorting in genetic algorithm Ⅱ(NSGA-Ⅱ)
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Coupling Study on the Problem Chain Teaching Mode and Moral Education Construction in Primary and Secondary Schools 被引量:1
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作者 PENG Hong-mei 《Journal of Literature and Art Studies》 2020年第8期738-742,共5页
The construction of moral education in primary and secondary schools is facingmany dilemmas,such as formalism,passivity,task-type,Tacitus trap and new media interaction.There is a high degree of coupling between the p... The construction of moral education in primary and secondary schools is facingmany dilemmas,such as formalism,passivity,task-type,Tacitus trap and new media interaction.There is a high degree of coupling between the progressive,stepped and interlocking supply of Problem Chain mode and the demand of moral education construction in primary and secondary schools.Problem Chain mode is helpful to solve the problems of teaching content,teaching effects and educational object in moral education construction in primary and secondary schools. 展开更多
关键词 problem chain moral education DILEMMAS COUPLING
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A Class of a Second-Order Two-Point Boundary Value Problem on a Measure Chain
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作者 杜增吉 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 2004年第S1期104-107,共4页
A class of second-order two-point boundary value problem on a measure chain was considered. Under some suitable conditions, by using the Leggett-Williams fixed point theorem in an appropriate cone, the existence of at... A class of second-order two-point boundary value problem on a measure chain was considered. Under some suitable conditions, by using the Leggett-Williams fixed point theorem in an appropriate cone, the existence of at least three positive solutions to this nonlinear problem was obtained. 展开更多
关键词 boundary value problem measure chains fixed point theorem
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An Algorithm for the Inverse Problem of Matrix Processing: DNA Chains, Their Distance Matrices and Reconstructing
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作者 Boris F. Melnikov Ye Zhang Dmitrii Chaikovskii 《Journal of Biosciences and Medicines》 CAS 2023年第5期310-320,共11页
We continue to consider one of the cybernetic methods in biology related to the study of DNA chains. Exactly, we are considering the problem of reconstructing the distance matrix for DNA chains. Such a matrix is forme... We continue to consider one of the cybernetic methods in biology related to the study of DNA chains. Exactly, we are considering the problem of reconstructing the distance matrix for DNA chains. Such a matrix is formed on the basis of any of the possible algorithms for determining the distances between DNA chains, as well as any specific object of study. At the same time, for example, the practical programming results show that on an average modern computer, it takes about a day to build such a 30 × 30 matrix for mnDNAs using the Needleman-Wunsch algorithm;therefore, for such a 300 × 300 matrix, about 3 months of continuous computer operation is expected. Thus, even for a relatively small number of species, calculating the distance matrix on conventional computers is hardly feasible and the supercomputers are usually not available. Therefore, we started publishing our variants of the algorithms for calculating the distance between two DNA chains, then we publish algorithms for restoring partially filled matrices, i.e., the inverse problem of matrix processing. Previously, we used the method of branches and boundaries, but in this paper we propose to use another new algorithm for restoring the distance matrix for DNA chains. Our recent work has shown that even greater improvement in the quality of the algorithm can often be achieved without improving the auxiliary heuristics of the branches and boundaries method. Thus, we are improving the algorithms that formulate the greedy function of this method only. . 展开更多
关键词 DNA chains Distance Matrix Optimization problem Restoring Algorithm Greedy Algorithm HEURISTICS
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Research on the Strategy of Generating Problem Chain in Senior High School Physics Teaching
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作者 LIWenjun 《外文科技期刊数据库(文摘版)教育科学》 2022年第3期132-135,共4页
The new curriculum standard requires high school physics teaching to adhere to a more open teaching concept, adhere to the physics teaching to highlight the experimental ability, awaken students' thinking with pro... The new curriculum standard requires high school physics teaching to adhere to a more open teaching concept, adhere to the physics teaching to highlight the experimental ability, awaken students' thinking with problems, and cultivate students' ability to ask, explore and solve problems. Therefore, the problem is not only a clue that runs through physics teaching, but also a starting point to explore new knowledge. Problem-based teaching is an effective way to cultivate students' scientific thinking and scientific methods. High school physics teachers should use the problem chain as a guide in teaching practice, according to students' cognitive status, to stimulate students' interest in learning and exploring science, so as to more efficiently promote the development of students' core quality in physics. 展开更多
关键词 high school physics teaching problem chains generate policy
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Discussion on the Special Teaching Design of the Problem Chain of "Basic Principles of Marxism"
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作者 HULing MAOMao 《外文科技期刊数据库(文摘版)教育科学》 2022年第4期072-075,共4页
The problem chain teaching method is a kind of teaching mode based on the problem consciousness guidance, which carries out the corresponding teaching activities through the interlocking problem design, guides the stu... The problem chain teaching method is a kind of teaching mode based on the problem consciousness guidance, which carries out the corresponding teaching activities through the interlocking problem design, guides the students to think deeply and explore with effective problems, and promotes the students' all-round development. Designing problem chains in the special teaching of "basic principles of Marxism" can effectively improve the teaching quality. The special teaching based on the problem chain design will help the "principle" class to become an ideological and political class with advanced "formula", "craftsmanship" exquisite, "packaging" fashion, and lead college students to establish a scientific world outlook, values and outlook on life. This paper focuses on the connotation, presentation and design of problem chains. 展开更多
关键词 problem chain special teaching DESIGN basic principles of Marxism
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纵向共同机构所有权的创新激励效应
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作者 罗进辉 戴芷歆 《经济管理》 北大核心 2026年第1期146-174,共29页
面对复杂严峻的国际地缘政治格局和“逆全球化”趋势,推动高水平科技自立自强,破解产业链供应链中存在的堵点和断点问题,是当前国家保障经济安全的战略要求。然而,囿于“敲竹杠”和信息壁垒问题,供应链上下游长期存在创新不足的困局。... 面对复杂严峻的国际地缘政治格局和“逆全球化”趋势,推动高水平科技自立自强,破解产业链供应链中存在的堵点和断点问题,是当前国家保障经济安全的战略要求。然而,囿于“敲竹杠”和信息壁垒问题,供应链上下游长期存在创新不足的困局。基于此,本文利用2007—2022年中国A股上市公司的年度数据,实证检验了纵向共同机构所有权对供应商高水平创新活动的影响效应及其作用机制。研究发现,纵向共同机构所有权能够发挥创新激励效应,显著提高供应商的发明专利申请量。机制分析表明,纵向共同机构所有权主要通过“敲竹杠”缓解效应和知识溢出效应两种机制提高了供应商高水平创新的意愿和能力。异质性分析显示,纵向共同机构所有权对供应商高水平创新的激励作用在面临高经济政策不确定性企业、高竞争行业企业、低知识产权保护地区企业、非国有企业、中小企业以及低数字化水平企业中表现得更强,呈现出典型的“扶弱”特征。此外,本文发现,纵向共同机构所有权还显著提高了供应商的创新效率;而且,相比横向共同所有权和纵向直接所有权,纵向共同机构所有权具有明显的创新增量效应。本文不仅丰富和拓展了供应链创新和共同所有权领域的研究文献,而且相关研究结论对于推进国家创新驱动发展战略和构建自主可控供应链体系的实践具有重要启示。 展开更多
关键词 纵向共同机构所有权 供应链 “敲竹杠”问题 供应商创新
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AI赋能的贯穿式案例-问题链物理化学教学模式的构建——以热力学第一定律为例
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作者 任冬梅 孙叔阳 赵岩 《云南化工》 2026年第1期151-155,共5页
构建了一种生成式AI辅助的贯穿式“案例-问题链”混合教学模式,其核心在于以单一真实工业案例覆盖整章知识点,打破传统教学中案例孤立、碎片化的局限,解决物理化学课程中学用脱节的问题。通过AI辅助将案例进一步生成逻辑严密、难度递进... 构建了一种生成式AI辅助的贯穿式“案例-问题链”混合教学模式,其核心在于以单一真实工业案例覆盖整章知识点,打破传统教学中案例孤立、碎片化的局限,解决物理化学课程中学用脱节的问题。通过AI辅助将案例进一步生成逻辑严密、难度递进的问题链,将抽象理论转化为阶梯式问题链,引导学生从概念理解向高阶能力逐层跃迁,减少学生对AI的深度依赖而导致的浅层学习。初步教学实践表明,采用该模式的2023级学生热力学章节测试平均成绩优于传统线下及纯线上教学模式,这为推动AI赋能教育提供了可借鉴的实践路径。 展开更多
关键词 生成式人工智能 贯穿式案例 问题链 物理化学 热力学第一定律
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问题链教学法在历史课堂中的三维重构
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作者 赵淑清 《科教文汇》 2026年第1期133-136,共4页
针对历史教学中问题链教学法的理论建构与实践创新问题,本文提出“时序性—因果性—解释性”三维问题链模型。研究通过构建包含事实、概念、方法、价值四个维度的“钻石模型”问题体系,结合虚拟现实技术创设具身化情境,并采用思维可视... 针对历史教学中问题链教学法的理论建构与实践创新问题,本文提出“时序性—因果性—解释性”三维问题链模型。研究通过构建包含事实、概念、方法、价值四个维度的“钻石模型”问题体系,结合虚拟现实技术创设具身化情境,并采用思维可视化评价体系,系统重构历史课堂教学范式。研究表明,问题链教学法通过结构化问题引导学生实现“事实确认—意义建构—价值反思”的螺旋认知发展,为历史学科核心素养落地提供了可操作路径,并提出需要关注问题梯度设计与教师专业能力建设等优化方向。 展开更多
关键词 问题链教学 历史 三维重构
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基于稳健供应链视角的“卡脖子”难题突破路径与对策研究
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作者 董文杰 闫丹丹 +2 位作者 陈绍庆 王文霞 唐菁菁 《江苏科技信息》 2026年第1期12-17,共6页
在当前全球化背景下,构建稳健供应链体系对国家经济安全和科技进步至关重要。我国在高端制造、新能源等关键领域面临“卡脖子”难题,其形成机理涉及战略规划、创新活动、核心要素、协同合作及政策体系等多方面的不足。突破此困境需从多... 在当前全球化背景下,构建稳健供应链体系对国家经济安全和科技进步至关重要。我国在高端制造、新能源等关键领域面临“卡脖子”难题,其形成机理涉及战略规划、创新活动、核心要素、协同合作及政策体系等多方面的不足。突破此困境需从多路径着手,如加强统一领导以统筹协调各方力量,优化举国体制营造良好创新环境,注重创新要素提升技术水平,秉持开放包容拓展国际市场,坚持全员参与发挥员工主体作用。以新产品研发为例,应推动改进性新产品向自主品牌高档新产品转变,助力国家级新产品成为替代性新产品,促使全新新产品发展为颠覆性新产品,将满足新需求的新产品打造为关键核心技术,从而实现供应链系统的持续优化与升级,为经济高质量发展提供坚实支撑。 展开更多
关键词 “卡脖子”难题 产业链供应链 韧性 关键核心技术 产品研发
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问题链教学法在高中物理教学中的应用
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作者 孙秀平 《科教导刊》 2026年第3期133-135,共3页
随着新课程改革的深入推进,高中物理教学亟须突破传统知识灌输模式,向核心素养培育转型。问题链教学法通过将复杂物理问题拆解为逻辑层层递进的问题序列,构建阶梯式认知路径,助力学生形成系统知识框架。该方法不仅能够激发探究动机,推... 随着新课程改革的深入推进,高中物理教学亟须突破传统知识灌输模式,向核心素养培育转型。问题链教学法通过将复杂物理问题拆解为逻辑层层递进的问题序列,构建阶梯式认知路径,助力学生形成系统知识框架。该方法不仅能够激发探究动机,推动批判性思维与创新能力发展,还能强化学生的知识迁移应用能力,实现从记忆理解到分析评价的高阶认知。 展开更多
关键词 问题链 高中物理 高效课堂 核心素养
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基于改进遗传算法的冷链物流配送路径优化
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作者 孙雨辉 潘大志 《西华师范大学学报(自然科学版)》 2026年第1期103-111,共9页
为确保生鲜产品按时按质从冷链配送中心送到客户点,综合考虑车辆制冷、碳排放以及与质量满意度相糅合的惩罚成本等因素,构建以总成本最小化为目标的冷链车辆路径优化模型,提出一种融合遗传算法和局部搜索的改进遗传算法求解并优化该问... 为确保生鲜产品按时按质从冷链配送中心送到客户点,综合考虑车辆制冷、碳排放以及与质量满意度相糅合的惩罚成本等因素,构建以总成本最小化为目标的冷链车辆路径优化模型,提出一种融合遗传算法和局部搜索的改进遗传算法求解并优化该问题。将改进遗传算法与其他4种优化算法运用到Solomon数据集中进行对比试验,同时对新鲜度敏感系数进行分析。试验结果发现,改进遗传算法优化模型的配送总成本最小,寻优性和稳定性具有明显的优势。 展开更多
关键词 冷链物流 车辆路径问题 敏感度 遗传算法 局部搜索
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巧用问题链培养学生高阶思维能力的策略研究
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作者 夏敏 《成才之路》 2026年第4期65-68,共4页
高阶思维是发生在较高认知水平层次上的心智活动或认知能力,这一能力的科学培养能有效提高学生的认知整合效率、问题解决能力等,为学生的终身学习提供源源不断的活力。教师在数学教学中利用问题链培养学生的高阶思维能力时,应遵循目标... 高阶思维是发生在较高认知水平层次上的心智活动或认知能力,这一能力的科学培养能有效提高学生的认知整合效率、问题解决能力等,为学生的终身学习提供源源不断的活力。教师在数学教学中利用问题链培养学生的高阶思维能力时,应遵循目标导向性、认知适配性、逻辑递进性等原则,以情境性、探究性、矛盾性、跨科性、反思性问题链,引导学生经历激活、提升、进阶、迁移、深化等思维阶段,促进学生高阶思维能力的不断提高。 展开更多
关键词 数学教学 问题链 高阶思维能力 能力培养 教学方式
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Downside Risk-Aversion Analysis for a Single-Stage Newsvendor Problem 被引量:1
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作者 YANG Lei GAO Chengxiu CHEN Kebing LI Jianbin 《Wuhan University Journal of Natural Sciences》 CAS 2007年第2期198-202,共5页
We extend the classical newsvendor problem by introducing a downside risk constraint from the perspective of inventory control. At the beginning of a replenishment period the newsvendor will place an order, then he wi... We extend the classical newsvendor problem by introducing a downside risk constraint from the perspective of inventory control. At the beginning of a replenishment period the newsvendor will place an order, then he will review the inventory level at the end of the period. If the inventory level is positive then he will bear the holding cost and if the inventory level is negative then he will bear the backorder cost. The optimal order quantity has a simple form. We analyze the form of the optimal order quantity when we restrict that the probability that the cost level is larger than or equal to a fixed cost constant is less than a fixed value of probability. At last, we analyze the case that the fixed cost constant is equal to the expected cost. 展开更多
关键词 supply chain newsvendor problem inventory management RISK
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A DNA Computing Model for the Graph Vertex Coloring Problem Based on a Probe Graph 被引量:8
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作者 Jin xu Xiaoli Qiang +2 位作者 Kai Zhang Cheng Zhang Jing Yang 《Engineering》 2018年第1期61-77,共17页
The biggest bottleneck in DNA computing is exponential explosion, in which the DNA molecules used as data in information processing grow exponentially with an increase of problem size. To overcome this bottleneck and ... The biggest bottleneck in DNA computing is exponential explosion, in which the DNA molecules used as data in information processing grow exponentially with an increase of problem size. To overcome this bottleneck and improve the processing speed, we propose a DNA computing model to solve the graph vertex coloring problem. The main points of the model are as follows: The exponential explosion prob- lem is solved by dividing subgraphs, reducing the vertex colors without losing the solutions, and ordering the vertices in subgraphs; and the bio-operation times are reduced considerably by a designed parallel polymerase chain reaction (PCR) technology that dramatically improves the processing speed. In this arti- cle, a 3-colorable graph with 61 vertices is used to illustrate the capability of the DNA computing model. The experiment showed that not only are all the solutions of the graph found, but also more than 99% of false solutions are deleted when the initial solution space is constructed. The powerful computational capability of the model was based on specific reactions among the large number of nanoscale oligonu- cleotide strands. All these tiny strands are operated by DNA self-assembly and parallel PCR. After thou- sands of accurate PCR operations, the solutions were found by recognizing, splicing, and assembling. We also prove that the searching capability of this model is up to 0(3^59). By means of an exhaustive search, it would take more than 896 000 years for an electronic computer (5 x 10^14 s-1) to achieve this enormous task. This searching capability is the largest among both the electronic and non-electronic computers that have been developed since the DNA computing model was proposed by Adleman's research group in 2002 (with a searching capability of 0(2^20)). 展开更多
关键词 DNA computing GRAPH VERTEX COLORING problem POLYMERASE chain reaction
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On One Possibility of Closuring the Chain of Equations for Statistical Moments in Turbulence Theory
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作者 Edward V. Teodorovich 《Journal of Modern Physics》 2013年第1期56-63,共8页
The paper concerns the problem on statistical description of the turbulent velocity pulsations by using the method of characteristic functional. The equations for velocity covariance and Green’s function, which descr... The paper concerns the problem on statistical description of the turbulent velocity pulsations by using the method of characteristic functional. The equations for velocity covariance and Green’s function, which describes an average velocity response to external force action, have been obtained. For the nonlinear term in the equation for velocity covariance, it has been obtained an exact representation in the form of two terms, which can be treated as describing a momentum transport due to turbulent viscosity and action of effective random forces (within the framework of traditional phenomenological description, the turbulent viscosity is only accounted for). Using a low perturbation theory approximation for high statistical moments, a scheme of closuring the chain of equations for statistical moments is proposed. As the result, we come to a closed set of equations for velocity covariance and Green’s function, the solution to which corresponds to summing up a certain infinite subsequence of total perturbation series. 展开更多
关键词 Random VELOCITY Field Statistical DESCRIPTION Characteristic Functional chain of EQUATIONS for MOMENTS problem of Closuring
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Markov Chain Monte Carlo Solution of Laplace’s Equation in Axisymmetric Homogeneous Domain
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作者 Adebowale E. Shadare Matthew N. O. Sadiku Sarhan M. Musa 《Open Journal of Modelling and Simulation》 2019年第4期203-216,共14页
With increasing complexity of today’s electromagnetic problems, the need and opportunity to reduce domain sizes, memory requirement, computational time and possibility of errors abound for symmetric domains. With sev... With increasing complexity of today’s electromagnetic problems, the need and opportunity to reduce domain sizes, memory requirement, computational time and possibility of errors abound for symmetric domains. With several competing computational methods in recent times, methods with little or no iterations are generally preferred as they tend to consume less computer memory resources and time. This paper presents the application of simple and efficient Markov Chain Monte Carlo (MCMC) method to the Laplace’s equation in axisymmetric homogeneous domains. Two cases of axisymmetric homogeneous problems are considered. Simulation results for analytical, finite difference and MCMC solutions are reported. The results obtained from the MCMC method agree with analytical and finite difference solutions. However, the MCMC method has the advantage that its implementation is simple and fast. 展开更多
关键词 Laplace’s Equation AXISYMMETRIC problem INHOMOGENEOUS DIRICHLET Boundary Conditions MARKOV chain MONTE Carlo (MCMC)
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Green supply chain management development and performance evaluation
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作者 WenyanWang 《International Journal of Technology Management》 2014年第11期118-120,共3页
China' s rapid economic development in recent years, more and more prompted serious environmental problems, especially some high pollution enterprises, has been a serious threat to the survival of mankind. At the sam... China' s rapid economic development in recent years, more and more prompted serious environmental problems, especially some high pollution enterprises, has been a serious threat to the survival of mankind. At the same time, both at home and abroad pay more and more attention to environmental problems caused in harm enterprises enhance their efficiency at the same time, the international and domestic have formulated a series of laws and regulations, the adverse effects of economic activity on the environment caused by the restriction of the enterprise. I studied the development and performance evaluation of green supply chain management, supply from the supply chain management strategy of a successful transition to the green supply chain management decision support for enterprises. 展开更多
关键词 green supply chain management environmental problems restrict economic activity strategic transformation
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问题思维:新质学习力的元素养 被引量:10
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作者 沈书生 《苏州大学学报(教育科学版)》 北大核心 2025年第1期63-72,共10页
劳动者是生产力的核心要素,形成和发展新质生产力,需要新质人才。新质人才能否适应时代所需并推动生产力发展,取决于学习力。学习力是个体认识世界的过程中形成的面向未来的力量,具有学习力的个体建立了主体自觉并形成了主体责任,才能... 劳动者是生产力的核心要素,形成和发展新质生产力,需要新质人才。新质人才能否适应时代所需并推动生产力发展,取决于学习力。学习力是个体认识世界的过程中形成的面向未来的力量,具有学习力的个体建立了主体自觉并形成了主体责任,才能够与富技术共同作用,不断营造新生态。对话是个体与外部世界交往的主要方式,也是个体成长的动因,内容生成式人工智能创造了人类对话的新样式,为个体的认知机会、认知行为与结果等提供了更多可能性与不确定性。认知不仅仅是简单吸收,更是追问与思考,将“问题思维”作为推动个体建立主体责任的关键元素养,可以推动个体基于思维形成高质量问题,基于问题形成高品质思维。以问题意识锚定问题思维的作用点,以问题链彰显问题思维的新质属性,问题思维就可以促进个体形成认知之脉。发展个体的问题思维元素养,可以唤醒个体的主体意识,使学习力发生质变,并推动形成新质学习力,促进个体的健康成长。 展开更多
关键词 新质生产力 新质学习力 问题思维 问题意识 问题链 认知之脉
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