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Is Evidence-Based Conservation Applied in Urban Forestry? A Case Study from Toronto, Canada
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作者 Adam R. Martin W. Eric Davies +1 位作者 Danijela Puric-Mladenovic Sandy M. Smith 《Open Journal of Forestry》 2014年第1期28-33,共6页
Evidence-based conservation seeks to incorporate sound scientific information into environmental decision making. The application of this concept in urban forest management has tremendous potential, but to date has be... Evidence-based conservation seeks to incorporate sound scientific information into environmental decision making. The application of this concept in urban forest management has tremendous potential, but to date has been little applied, largely because existing scientific studies emphasize the importance of urban forests in large-scale ecological and anthropogenic processes, but in practice, scientific evidence is ostensibly incorporated into North American urban forest management only when deciding the fate of individual trees. Even under these disjunctive conditions, the degree to which evidence influences tree-level decisions remains debatable. In analyzing preliminary data from a case study from Toronto, Canada, we sought to test if and how scientific evidence factored into the decision to remove or preserve 53 trees, located in close proximity to a provincially significant area of natural and scientific interest (ANSI). We found that by far the strongest tree-level correlate of the recommendation to remove or preserve trees was whether or not an individual tree was in conflict with proposed development. In comparison, species identity, tree condition, and suitability for conservation were statistically unrelated to the final recommendation. Our findings provide the basis to expand our analysis to multiple case studies across Canada, and internationally. Furthermore, when interpreted with available research and policy, our preliminary (and future) analysis highlights clear opportunities where scientific evidence can and should be readily incorporated into urban forestry management and policy. 展开更多
关键词 ANSI ARBORICULTURE Black OAK EVIDENCE-BASED Conservation Land Use Planning TORONTO Tree Bylaw URBAN Forestry URBAN Forest Policy
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GIS Spatial-Temporal Modeling of Water Systems in Greater Toronto Area, Canada 被引量:1
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作者 ChengQiuming ZhangGeorge +1 位作者 LuCindy KoConnie 《Journal of China University of Geosciences》 SCIE CSCD 2004年第3期275-282,共8页
Modeling landscape with high-resolution digital elevation model (DEM) in a geographic information system can provide essential morphological and structural information for modeling surface processes such as geomorphol... Modeling landscape with high-resolution digital elevation model (DEM) in a geographic information system can provide essential morphological and structural information for modeling surface processes such as geomorphologic process and water systems. This paper introduces several DEM-based spatial analysis processes applied to characterize spatial distribution and their interactions of ground and surface water systems in the Greater Toronto Area (GTA), Canada. The stream networks and drainage basin systems were derived from the DEM with 30 m resolution and the regularities of the surface stream and drainage patterns were modeled from a statistical/multifractal point of view. Together with the elevation and slope of topography, other attributes defined from modeling the stream system, and drainage networks were used to associate geological, hydrological and topographical features to water flow in river systems and the spatial locations of artesian aquifers in the study area. Stream flow data derived from daily flow measurements recorded at river gauging stations for multi-year period were decomposed into 'drainage-area dependent' and 'drainage-area independent' flow components by two-step 'frequency' and 'spatial' analysis processes. The latter component was further demonstrated to relate most likely to the ground water discharge. An independent analysis was conducted to model the distribution of aquifers with information derived from the records of water wells. The focus was given on quantification of the likelihood of ground water discharge to river and ponds through flowing wells, springs and seepages. It has been shown that the Oak Ridges Moraine (ORM) is a unique glacial deposit that serves as a recharge layer and that the aquifers in the ORM underlain by Hilton Tills and later deposits exposed near the steep slope zone of the ridges of ORM provide significant discharge to the surface water systems (river flow and ponds) through flowing wells, springs and seepages. Various statistics (cross- and auto-correlation coefficients, fractal R/S exponent) were used in conjunction with GIS to demonstrate the influence of land types, topography and geometry of drainage basins on short- and long-term persistence of river flows as well as responding time to precipitation events. The current study has provided not only insight in understanding the interaction of water systems in the GTA, but also a base for further establishment of an on-line GIS system for predicting spatial-temporal changes of river flow and groundwater level in the GTA. 展开更多
关键词 GIS drainage system water flow PRECIPITATION flowing wells prediction.
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Training in translational research for graduate students at the University of Toronto
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作者 Ori D. Rotstein 《中国病理生理杂志》 CAS CSCD 北大核心 2009年第11期2242-2242,共1页
The Institute of Medical Science (IMS) was established as an institute within the School of Graduate Studies at the University of Toronto in 1968 to serve as a graduate unit for the Clinical Departments in the Faculty... The Institute of Medical Science (IMS) was established as an institute within the School of Graduate Studies at the University of Toronto in 1968 to serve as a graduate unit for the Clinical Departments in the Faculty of Medicine. In this role,the IMS offers a doctoral stream program in medical science leading to the Master of Science and Doctor of Philosophy degrees. Translational research,as a means of moving new discovery to improvement in patient outcome,has become a central theme of graduate education in our Institute. To this end,we have developed a curriculum offering which is intended to provide all new students with a defined skill set relevant to Translational Research and at the same time,to provide students with flexible offerings which would enhance their specific research programs. The course,spread over two years,will have three separate components:(1) there will be lectures focusing on research fundamentals and the basics of translational research; (2) there will be student presentations to hone presentation skills and get valuable feedback from fellow students and faculty mentors; (3) there will be elective modules,where students can select from a number of course offerings in order to round out training. These modules include subjects such as the fundamentals of clinical trials,the basics of qualitative research,an approach to the role of proteomics and genomics in research and the business of science. As part of this modular program,we have created a program 'clinical exposure for non-clinicians' with the hope that graduate students will be able to gain some understanding of the clinical relevance of their research activities. Over time,these modular offerings will be expanded based on a needs assessment from our students. The presentation will describe the IMS and its mission and will overview the structure and content of this course offering. 展开更多
关键词 研究生教育 多伦多大学 转化型 训练 医学科学 博士学位 医学院 硕士学位
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基于最大瓦解结构的科学研究前沿关键节点识别与演化路径分析
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作者 白如江 刘琦 +4 位作者 石文秀 王天一 张新雨 牛湘荷 刘睿琳 《现代情报》 北大核心 2026年第1期52-64,共13页
[目的/意义]通过最大瓦解结构准确识别科学研究前沿中的关键节点并追踪其演化路径,为把握领域发展规律、优化科研资源配置提供支持,突破现有研究聚焦孤立节点的局部特征,以及难以捕捉知识网络中具有协同作用且对全局连通性有级联破坏力... [目的/意义]通过最大瓦解结构准确识别科学研究前沿中的关键节点并追踪其演化路径,为把握领域发展规律、优化科研资源配置提供支持,突破现有研究聚焦孤立节点的局部特征,以及难以捕捉知识网络中具有协同作用且对全局连通性有级联破坏力的关键节点集合的问题。[方法/过程]以量子通信领域为例,基于2015—2024年Web of Science的6538篇文献构建关键词共现网络,融合多中心性指标并利用熵权法评估节点重要性,采用贪心算法识别MDS,分析其功能协同特征与演化轨迹。[结果/结论]研究表明,MDS仅占网络规模的18%~22%,移除该集合后网络最大连通组件规模下降超过70%,效果显著优于传统方法。关键节点在功能上呈现“主题—方法—工具—目标”的互补协同结构,其演化路径清晰展示了量子通信从理论奠基、技术攻坚到应用落地的三阶段发展轨迹,验证了MDS框架的有效性和实用性。 展开更多
关键词 科学研究前沿 关键节点识别 最大瓦解结构 网络瓦解 演化路径
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mTORC1 and mTORC2 synergy in human neural development, disease, and regeneration
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作者 Navroop K.Dhaliwal Julien Muffat Yun Li 《Neural Regeneration Research》 2026年第4期1552-1553,共2页
The mechanistic target of rapamycin(m TOR) is a serine/threonine kinase that plays a pivotal role in cellular growth, proliferation, survival, and metabolism. In the central nervous system(CNS), the mTOR pathway regul... The mechanistic target of rapamycin(m TOR) is a serine/threonine kinase that plays a pivotal role in cellular growth, proliferation, survival, and metabolism. In the central nervous system(CNS), the mTOR pathway regulates diverse aspects of neural development and function. Genetic mutations within the m TOR pathway lead to severe neurodevelopmental disorders, collectively known as “mTORopathies”(Crino, 2020). Dysfunctions of m TOR, including both its hyperactivation and hypoactivation, have also been implicated in a wide spectrum of other neurodevelopmental and neurodegenerative conditions, highlighting its importance in CNS health. 展开更多
关键词 m tor neural development mtorc central nervous system cns mtor neurodevelopmental disorders neurodegenerative conditions
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A method improving historical accuracy regarding notable figures focused on the biography of Emily Stowe
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作者 Carol Nash 《History and Philosophy of Medicine》 2026年第1期1-21,共21页
Background:A significant challenge regarding notable historical figures is determining the accuracy of the words and actions attributed to them with the limited available evidence,when their biographers have presented... Background:A significant challenge regarding notable historical figures is determining the accuracy of the words and actions attributed to them with the limited available evidence,when their biographers have presented a biased life assessment.Lauded as a founding suffragette,the first female school principal,and the first white female practicing physician in Canada,Dr.Emily Stowe did not help historians.She destroyed her records,leaving her life story to be told by her daughter,who portrayed her as a heroine–a view that has persisted since the start of the 20th century.To improve the accuracy of assessing the life of Emily Stowe,as much information as possible about Stowe must be collected and interpreted.Methods:Presented is a narrative research method for analyzing historical figures that examines 22 life-changing events in the life of Stowe by answering six types of questions about each event:when,where,who,what,how,and why.Results:This narrative research,representing a psychoanalytic research process,finds that much of the repeated story of Stowe is either exaggerated or likely false.Conclusion:Following the example of Emily Stowe,this unique method is applicable for improving the historical accuracy in assessing the lives of other notable figures.It represents a method extendable to those currently alive,outside the public eye,searching to develop their own narrative. 展开更多
关键词 historical figures Emily Stowe suffragettes female physicians Canada narrative research psychoanalytic research
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Estimating effective reproduction number using generation time versus serial interval,with application to COVID-19 in the Greater Toronto Area,Canada 被引量:3
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作者 Jesse Knight Sharmistha Mishra 《Infectious Disease Modelling》 2020年第1期889-896,共8页
BACKGROUND.The effective reproduction number Re(t)is a critical measure of epidemic potential.Re(t)can be calculated in near real time using an incidence time series and the generation time distribution:the time betwe... BACKGROUND.The effective reproduction number Re(t)is a critical measure of epidemic potential.Re(t)can be calculated in near real time using an incidence time series and the generation time distribution:the time between infection events in an infector-infectee pair.In calculating Re(t),the generation time distribution is often approximated by the serial interval distribution:the time between symptom onset in an infector-infectee pair.However,while generation time must be positive by definition,serial interval can be negative if transmission can occur before symptoms,such as in COVID-19,rendering such an approximation improper in some contexts.METHODS.We developed a method to infer the generation time distribution from parametric definitions of the serial interval and incubation period distributions.We then compared estimates of Re(t)for COVID-19 in the Greater Toronto Area of Canada using:negative-permitting versus non-negative serial interval distributions,versus the inferred generation time distribution.RESULTS.We estimated the generation time of COVID-19 to be Gamma-distributed with mean 3.99 and standard deviation 2.96 days.Relative to the generation time distribution,non-negative serial interval distribution caused overestimation of Re(t)due to larger mean,while negative-permitting serial interval distribution caused underestimation of Re(t)due to larger variance.IMPLICATIONS.Approximation of the generation time distribution of COVID-19 with non-negative or negative-permitting serial interval distributions when calculating Re(t)may result in over or underestimation of transmission potential,respectively. 展开更多
关键词 Reproduction number Generation time Serial interval Incubation period COVID-19
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Regenerating Narrative Inquiry for Teacher Growth on a Toronto-Shanghai Sister School Partnership Landscape
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作者 Yishin KHOO 《Frontiers of Education in China》 2017年第2期180-199,共20页
In this paper,I demonstrate a way of conducting narrative inquiry that is oriented towards understanding and improving teachers’experiences in a particular Toronto-Shanghai/West-East Sister School reciprocal learning... In this paper,I demonstrate a way of conducting narrative inquiry that is oriented towards understanding and improving teachers’experiences in a particular Toronto-Shanghai/West-East Sister School reciprocal learning partnership.I show how this narrative inquiry process is informed by a Deweyan way of thinking about experience and is enriched by the Confucian idea of being a good vip.I illustrate how this inquiry process involves teachers and researchers as collaborative and reciprocal learners on the Dao of further personal and professional growth and learning.I suggest that conducting narrative inquiry in a Canada-China interschool setting could give rise to West-East reciprocal learning communities that have the potential of bridging the cultural and historical narratives that underlie Chinese and North American education.It could also create the harmonious and democratic educational conditions for fostering global citizens as learners in our 21st century. 展开更多
关键词 narrative inquiry Sister School partnership teacher growth West-East reciprocal learning
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Corrigendum to“Estimating effective reproduction number using generation time versus serial interval,with application to covid-19 in the Greater Toronto Area,Canada”[Infectious Disease Modelling 5(2020)889e896]
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作者 Jesse Knight Sharmistha Mishra 《Infectious Disease Modelling》 2022年第4期777-777,共1页
In the originally published version of this work,the parametersθ^(*)=[a,b]were calculated incorrectly because the Kullback-Leibler divergence was defined in the wrong direction in our code.The impact on generation ti... In the originally published version of this work,the parametersθ^(*)=[a,b]were calculated incorrectly because the Kullback-Leibler divergence was defined in the wrong direction in our code.The impact on generation time parameters and statistics is as follows(original/fixed):shape(a):1.813/1.633,scale(b):2.199/2.498,mean:3.99/4.08,SD:2.96/3.19.The qualitative interpretation of results is unchanged.We sincerely apologize for this error.The error correction is shown here:https://github.com/mishra-lab/covid-r/commit/aaef512 and a corrected draft manuscript is shown here. 展开更多
关键词 unchanged qualitative correction
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Projections of the transmission of the Omicron variant for Toronto,Ontario,and Canada using surveillance data following recent changes in testing policies
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作者 Pei Yuan Elena Aruffo +4 位作者 Yi Tan Liu Yang Nicholas HOgden Aamir Fazil Huaiping Zhu 《Infectious Disease Modelling》 2022年第2期83-93,共11页
At the end of 2021,with the rapid escalation of COVID19 cases due to the Omicron variant,testing centers in Canada were overwhelmed.To alleviate the pressure on the PCR testing capacity,many provinces implemented new ... At the end of 2021,with the rapid escalation of COVID19 cases due to the Omicron variant,testing centers in Canada were overwhelmed.To alleviate the pressure on the PCR testing capacity,many provinces implemented new strategies that promote self testing and adjust the eligibility for PCR tests,making the count of new cases underreported.We designed a novel compartmental model which captures the new testing guidelines,social behaviours,booster vaccines campaign and features of the newest variant Omicron.To better describe the testing eligibility,we considered the population divided into high risk and non-highrisk settings.The model is calibrated using data from January 1 to February 9,2022,on cases and severe outcomes in Canada,the province of Ontario and City of Toronto.We conduct analyses on the impact of PCR testing capacity,self testing,different levels of reopening and vaccination coverage on cases and severe outcomes.Our results show that the total number of cases in Canada,Ontario and Toronto are 2.34(95%CI:1.22e3.38),2.20(95%CI:1.15e3.72),and 1.97(95%CI:1.13e3.41),times larger than reported cases,respectively.The current testing strategy is efficient if partial restrictions,such as limited capacity in public spaces,are implemented.Allowing more people to have access to PCR reduces the daily cases and severe outcomes;however,if PCR test capacity is insufficient,then it is important to promote self testing.Also,we found that reopening to a pre-pandemic level will lead to a resurgence of the infections,peaking in late March or April 2022.Vaccination and adherence to isolation protocols are important supports to the testing policies to mitigate any possible spread of the virus. 展开更多
关键词 PCR testing SELF-TESTING Booster dose Social behavior Mathematical model COVID-19 Omicron Exit strategy
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人工智能驱动管理决策:应用、感知与偏见 被引量:6
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作者 谷炜 刘亚金 +1 位作者 Lu Feng Susan 闫相斌 《中国管理科学》 北大核心 2025年第5期99-112,共14页
近年来,由人工智能引领的新一轮科技创新和产业变革,突破了传统管理决策系统受限于数据可获取性和模型可解性的局限性,使得自动化的数据分析和智能化的决策支持成为可能。同时,在数字经济浪潮的推动下,人工智能技术已广泛渗透到企业运... 近年来,由人工智能引领的新一轮科技创新和产业变革,突破了传统管理决策系统受限于数据可获取性和模型可解性的局限性,使得自动化的数据分析和智能化的决策支持成为可能。同时,在数字经济浪潮的推动下,人工智能技术已广泛渗透到企业运营决策的各个环节,这为实现数字化管理创造了新的机遇,同时也给管理决策研究带来了新的挑战。本文从人工智能在不同商业环境的应用、人们对人工智能的感知和人工智能算法的偏见这三个方面对人工智能驱动的管理决策进行梳理、归纳和展望,并提出了未来研究的趋势和方向,为开展更深层次的研究提供了思路,为企业管理者和政策制定者进行科学决策提供参考,推动人工智能驱动管理决策的理论研究与商业实践。 展开更多
关键词 人工智能 管理与决策 机器学习 人机交互
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碳排放权交易赋能中国区域碳中和建设——基于能源技术创新中介效应的视角 被引量:1
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作者 张意翔 李峰 李政语 《南海学刊》 2025年第2期65-76,共12页
碳排放权交易和能源技术创新是中国碳中和实现程度的重要影响因素。基于2002—2022年中国30个省份的面板数据,在运用TOPSIS熵权法对碳中和实现程度和能源技术创新能力进行评价的基础上,运用多期双重差分模型揭示碳排放权交易对中国区域... 碳排放权交易和能源技术创新是中国碳中和实现程度的重要影响因素。基于2002—2022年中国30个省份的面板数据,在运用TOPSIS熵权法对碳中和实现程度和能源技术创新能力进行评价的基础上,运用多期双重差分模型揭示碳排放权交易对中国区域碳中和实现程度的直接和间接影响。研究发现,全国及三大区域的碳中和实现程度均得到提高,碳排放权交易能在整体上推动中国碳中和的实现,能源技术创新能加大碳排放权交易对区域碳中和实现程度的正面影响,但经济发展模式对碳中和建设促进作用不显著,在一定程度上减弱了碳排放权交易的影响。因此,完善政策内容,促进碳交易市场与能源技术创新的有机融合;实施差异化区域政策;加快绿色转型,促进经济结构低碳化是提高中国碳中和实现程度的关键。 展开更多
关键词 碳中和 碳排放权交易 能源技术创新
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中加“共有的教育合作故事”:大学的作用与未来展望——许美德教授专访
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作者 许美德 金国 《苏州大学学报(教育科学版)》 北大核心 2025年第1期82-91,共10页
在中国与加拿大教育合作交流的历史中,1983—2001年这一时期尤其值得关注。在此期间,三个国家级项目得以实施,两国数十所高校参与其中,合作内容涉及管理、农业、教育、工程、医学、环境等诸多领域。这些教育合作促进了中国社会的转型发... 在中国与加拿大教育合作交流的历史中,1983—2001年这一时期尤其值得关注。在此期间,三个国家级项目得以实施,两国数十所高校参与其中,合作内容涉及管理、农业、教育、工程、医学、环境等诸多领域。这些教育合作促进了中国社会的转型发展,加方也从中受益。许美德教授在其新著中记述了这一渐被遗忘的中加“共有的教育合作故事”。许美德教授长期关注中国高等教育,致力于促进中西方之间的教育交流。她认为,大学应该在国际舞台上发挥更为积极的作用和影响,促进文明对话与国际理解。中国学者在开展中西文化交流时,也需要将目光投向东方的其他国家或者其他文明。中加两国的大学和知识分子可以共同努力,通过文化间的相互交流、理解与借鉴,探索实现不同文明和谐共处、共同发展的适宜路径。 展开更多
关键词 教育合作 教育交流 文明对话 国际理解
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文明的对话:对高等教育国际化的重审与前瞻
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作者 许美德 吴寒天 刘继安 《高校教育管理》 北大核心 2025年第3期15-21,共7页
国际化可被视为现代大学自中世纪肇始即具有的内生属性。现代大学模式扩散至后发国家后与当地文化在冲突和互动中交融。大学不仅成为人类知识与文明交流互鉴的桥梁,其国际化进程也在后发国家的现代化进程中扮演重要角色。出于对亨廷顿... 国际化可被视为现代大学自中世纪肇始即具有的内生属性。现代大学模式扩散至后发国家后与当地文化在冲突和互动中交融。大学不仅成为人类知识与文明交流互鉴的桥梁,其国际化进程也在后发国家的现代化进程中扮演重要角色。出于对亨廷顿文明冲突论的反思,大学的独特性使其作为文明对话的平台从而避免文明冲突成为可能。儒家思想使中国大学在国际化进程中为促进国际和谐作出贡献。大学拥有知识生产和传播中心以及个体间思想交流枢纽的双重身份,它的文明职能无法被其他类型机构取代。大学促进文明对话最为直接和有效的形式是为来自不同文化的青年人营造有形或无形的交流空间。 展开更多
关键词 高等教育国际化 文明对话 文化冲突论 中国大学 儒家文化 文明职能
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图书情报领域多层网络模型构建方法、应用及发展趋势
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作者 白如江 牛湘荷 +2 位作者 何颖 张新雨 刘睿琳 《数字图书馆论坛》 2025年第7期54-62,共9页
随着数据量的激增以及自然语言处理等智能技术的发展,图书情报领域面临着日益复杂的网络结构和多样化的关系模式,远非单层网络所能刻画。本研究旨在构建适用于图书情报领域普遍研究场景的多层网络模型方法体系,以期推动多层网络在该领... 随着数据量的激增以及自然语言处理等智能技术的发展,图书情报领域面临着日益复杂的网络结构和多样化的关系模式,远非单层网络所能刻画。本研究旨在构建适用于图书情报领域普遍研究场景的多层网络模型方法体系,以期推动多层网络在该领域的深度应用从“案例化”向“范式化”转变。首先,对图书情报领域传统单层网络和现阶段多层网络的应用进行了梳理,明确其构建方法缺乏系统探讨的现状。其次,从数据收集、网络构建与算法分析3个层面提出图书情报领域多层网络一般模型的构建方法。最后,以数据要素与数据治理、图书馆智慧服务、数字人文与文化遗产智能计算3个热点方向为例,对多层网络在图书情报领域的具体应用进行阐释,并指出图书情报领域多层网络在多模态节点扩展、网络动力学研究与网络结构聚合维度上的发展趋势。 展开更多
关键词 图书情报 多层网络 网络构建 网络应用 发展趋势 研究方法
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电路功率及其分量的定义解析与测算
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作者 朱明 朱嘉慧 《电工技术》 2025年第23期11-20,共10页
电路分为单相、两相和三相三种形式,其功率及其分量与电路的组成、相间对称性、线性度、激励形态等多种因素密切相关,导致了功率分析解算的复杂性。在不同的激励形态下,不同的功率分量组成可反映不同的电路结构特征,因此电路功率及其分... 电路分为单相、两相和三相三种形式,其功率及其分量与电路的组成、相间对称性、线性度、激励形态等多种因素密切相关,导致了功率分析解算的复杂性。在不同的激励形态下,不同的功率分量组成可反映不同的电路结构特征,因此电路功率及其分量的研究具有重要意义。对电路的结构、功率分量的物理量意义和工程应用进行系统研究,提出了统一模式的定义和折叠模式的定义两种功率分量定义形式,以及两种定义下功率分量的物理意义和适用场景;以复合电路的功率及其分量为基础,提出了直流激励、简谐激励、多谐激励下单相电路、两相电路、三相电路的功率及其分量的表达式,以及功率测算的工程计量公式,基本厘清了电路的功率体系。 展开更多
关键词 功率体系 全总功率 全总无功 相异无功 杂散无功
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普联电路的系统整体解析原理
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作者 朱明 朱嘉慧 《电工技术》 2025年第19期110-119,共10页
电路模型横跨在工程和数学之间,以多样性、灵活性和完备性成为工程应用与数学工具之间的桥梁。全面梳理了线性电路模型相关的知识,提出了电路分类中最为复杂的一类电路——受控源电路的系统整体解析方法,并在静态电路、稳态电路、运算... 电路模型横跨在工程和数学之间,以多样性、灵活性和完备性成为工程应用与数学工具之间的桥梁。全面梳理了线性电路模型相关的知识,提出了电路分类中最为复杂的一类电路——受控源电路的系统整体解析方法,并在静态电路、稳态电路、运算电路与暂态电路,以及这些电路的实电路与复电路中得到充分地应用,有助于全面、整体、系统地了解、理解与分析求解线性电路,掌握线性电路的系统分析方法,并完善电路的知识体系。 展开更多
关键词 普联电路 耦合电路 控源电路 暂态电路 系统整体解析原理 惰性变量法解析原理
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系统四层次模型与反馈闭环电路解算方法
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作者 朱明 朱嘉慧 《电工技术》 2025年第15期53-65,共13页
放大电路是模拟电子技术的核心内容,而反馈放大电路是模拟电子技术中分析解算的难点。从双端口网络模型与特性出发,总结了反馈放大电路的基本原理,提出了系统四层次模型表达的概念和电路网络的方向性判断三原理,重新给出了理想运放的判... 放大电路是模拟电子技术的核心内容,而反馈放大电路是模拟电子技术中分析解算的难点。从双端口网络模型与特性出发,总结了反馈放大电路的基本原理,提出了系统四层次模型表达的概念和电路网络的方向性判断三原理,重新给出了理想运放的判定标准;提出了单闭环系统的分类与三种单闭环反馈系统的分析方法,给出了单闭环反馈电路解算的实例,并给出了内稳闭环系统的概念与稳定性判据,由此构建反馈闭环放大电路的知识体系,以期有效地帮助学生理解和掌握反馈放大电路相关的理论知识。 展开更多
关键词 系统四层次模型 双端口网络模型 反馈闭环 方向性判断三原理 内稳系统 稳定性判据
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知识外交版图上的中国职业教育
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作者 查强 张慧 《世界教育信息》 2025年第6期3-12,共10页
伴随知识在全球范围内流动与价值的日益凸显,知识外交成为国际交流的重要趋势。对中国来说,推动经济社会发展、提升影响力和构建人类命运共同体的内在需求,共同驱动知识外交的发展。教育是知识外交的重要载体,职业教育在知识外交中占据... 伴随知识在全球范围内流动与价值的日益凸显,知识外交成为国际交流的重要趋势。对中国来说,推动经济社会发展、提升影响力和构建人类命运共同体的内在需求,共同驱动知识外交的发展。教育是知识外交的重要载体,职业教育在知识外交中占据独特地位,主要表现为完备的职教体系能够满足知识外交多元的需求,齐全的职教门类契合全球南方国家的发展需求,以及职业教育国际交流具有更强的实用性和通用性。因此,相比其他教育类型,职业教育国际化进程在一些方面的条件和准备更充分。以职业教育推进知识外交,要做好顶层设计,明确职业教育在知识外交中的定位;强化职业教育品牌建设,提升职业教育国际影响力;构建职业教育共同体,深化国际合作与交流;同时融合数字技术,创新职业教育贡献于知识外交的模式。 展开更多
关键词 职业教育 知识外交 独特优势
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中国创业持续性的时空特征及其影响因素 被引量:1
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作者 陈广平 王琛 刘志高 《地理科学进展》 北大核心 2025年第3期460-477,共18页
创业持续性研究对于诊断区域经济可持续发展能力和识别空间失衡问题具有重要意义。论文基于1989-2022年长时间序列城市尺度的创业数据,利用皮尔逊相关系数、核密度估计等方法探究了中国261个城市创业率的持续时间跨度、强度及时空演化... 创业持续性研究对于诊断区域经济可持续发展能力和识别空间失衡问题具有重要意义。论文基于1989-2022年长时间序列城市尺度的创业数据,利用皮尔逊相关系数、核密度估计等方法探究了中国261个城市创业率的持续时间跨度、强度及时空演化特征。通过构建区域的制度性、历史性、结构性和先天性因素四维度分析框架,采用空间杜宾误差模型,探讨了长期以来持续影响中国城市创业率的因素及其空间效应。研究发现:(1)观测期内中国城市创业活动具有一定程度的持续性,并且存在4个明显的持续时间段,每个持续时段的时间跨度为8~15年;(2) 1989年以来,中国城市创业持续性呈减弱趋势,其中2008—2013年的创业持续性最强,超过一半(54.02%)城市的创业率等级保持不变;(3)中国创业持续性现象主要发生在低创业水平的城市;(4)长期正向作用于城市创业率的因素包括城市行政等级、创业文化、历史重大基础设施和沿海性,而历史人口密度和地形起伏度是长期抑制地区创业水平的重要因素,随着时间推移,知识储备量和国有企业数量占比的作用效果由正转负。研究结论为制定区域经济协调可持续发展政策提供了理论支撑。 展开更多
关键词 创业活动 持续性 路径依赖 空间依赖 空间杜宾误差模型
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