在MLIS授予单位迅速扩张的背景下,如何保障人才培养质量是MLIS教育面临的重要问题。文章以课程建设为观察点,调查U. S. News发布的MLIS榜单中的53所美国院校和我国66所MLIS院校的MLIS课程信息,借助BERTopic模型和余弦相似度算法,开展中...在MLIS授予单位迅速扩张的背景下,如何保障人才培养质量是MLIS教育面临的重要问题。文章以课程建设为观察点,调查U. S. News发布的MLIS榜单中的53所美国院校和我国66所MLIS院校的MLIS课程信息,借助BERTopic模型和余弦相似度算法,开展中美课程主题聚类分析及基于扎根理论的课程内容分析。研究发现中美课程均表现出强烈的职业导向性,在以图书馆职业为核心的基础上,MLIS教育出现向健康、政务、商务等多信息工作场景拓展的趋势。除MLIS教育共同发展趋势外,我国MLIS课程还具有重视文化保护的特点。同时,文章也发现我国MLIS课程在内容丰富性、差异性、业务细分等方面尚有提升空间,为此提出立足中国话语体系开发特色MLIS课程,对接区域需求开展差异化课程设计,强化行业合作以细化专业课程等建议。展开更多
文章根据《美国新闻与世界报道》(US News and World Report)2017年美国图书馆学情报学研究生院的排名结果,选取前十所院校分析图情硕士生(MLIS)的就业情况,调研发现:MLIS学生总体就业率普遍较高;以对口就业为主,但就业领域多样化;薪酬...文章根据《美国新闻与世界报道》(US News and World Report)2017年美国图书馆学情报学研究生院的排名结果,选取前十所院校分析图情硕士生(MLIS)的就业情况,调研发现:MLIS学生总体就业率普遍较高;以对口就业为主,但就业领域多样化;薪酬水平受就业单位和岗位影响较大;求职方式、人际关系、就业技能、薪酬与就业关系密切;职业满意度高。基于调研结果,文章从学科背景、个性化培养、就业能力等方面得出对我国MLIS教育人才培养的启示。展开更多
Conventional multilevel inverters often suffer from high harmonic distortion and increased design complexity due to the need for numerous power semiconductor components,particularly at elevated voltage levels.Addressi...Conventional multilevel inverters often suffer from high harmonic distortion and increased design complexity due to the need for numerous power semiconductor components,particularly at elevated voltage levels.Addressing these shortcomings,thiswork presents a robust 15-level PackedUCell(PUC)inverter topology designed for renewable energy and grid-connected applications.The proposed systemintegrates a sensor less proportional-resonant(PR)controller with an advanced carrier-based pulse width modulation scheme.This approach efficiently balances capacitor voltage,minimizes steady-state error,and strongly suppresses both zero and third-order harmonics resulting in reduced total harmonic distortion and enhanced voltage regulation.Additionally,a novel switching algorithm simplifies the design and implementation,further lowering voltage stress across switches.Extensive simulation results validate the performance under various resistive and resistive-inductive load conditions,demonstrating compliance with IEEE-519 THD standards and robust operation under dynamic changes.The proposed sensorless PR-controlled 15-PUC inverter thus offers a compelling,cost-effective solution for efficient power conversion in next-generation renewable energy systems.展开更多
文摘在MLIS授予单位迅速扩张的背景下,如何保障人才培养质量是MLIS教育面临的重要问题。文章以课程建设为观察点,调查U. S. News发布的MLIS榜单中的53所美国院校和我国66所MLIS院校的MLIS课程信息,借助BERTopic模型和余弦相似度算法,开展中美课程主题聚类分析及基于扎根理论的课程内容分析。研究发现中美课程均表现出强烈的职业导向性,在以图书馆职业为核心的基础上,MLIS教育出现向健康、政务、商务等多信息工作场景拓展的趋势。除MLIS教育共同发展趋势外,我国MLIS课程还具有重视文化保护的特点。同时,文章也发现我国MLIS课程在内容丰富性、差异性、业务细分等方面尚有提升空间,为此提出立足中国话语体系开发特色MLIS课程,对接区域需求开展差异化课程设计,强化行业合作以细化专业课程等建议。
文摘文章根据《美国新闻与世界报道》(US News and World Report)2017年美国图书馆学情报学研究生院的排名结果,选取前十所院校分析图情硕士生(MLIS)的就业情况,调研发现:MLIS学生总体就业率普遍较高;以对口就业为主,但就业领域多样化;薪酬水平受就业单位和岗位影响较大;求职方式、人际关系、就业技能、薪酬与就业关系密切;职业满意度高。基于调研结果,文章从学科背景、个性化培养、就业能力等方面得出对我国MLIS教育人才培养的启示。
文摘Conventional multilevel inverters often suffer from high harmonic distortion and increased design complexity due to the need for numerous power semiconductor components,particularly at elevated voltage levels.Addressing these shortcomings,thiswork presents a robust 15-level PackedUCell(PUC)inverter topology designed for renewable energy and grid-connected applications.The proposed systemintegrates a sensor less proportional-resonant(PR)controller with an advanced carrier-based pulse width modulation scheme.This approach efficiently balances capacitor voltage,minimizes steady-state error,and strongly suppresses both zero and third-order harmonics resulting in reduced total harmonic distortion and enhanced voltage regulation.Additionally,a novel switching algorithm simplifies the design and implementation,further lowering voltage stress across switches.Extensive simulation results validate the performance under various resistive and resistive-inductive load conditions,demonstrating compliance with IEEE-519 THD standards and robust operation under dynamic changes.The proposed sensorless PR-controlled 15-PUC inverter thus offers a compelling,cost-effective solution for efficient power conversion in next-generation renewable energy systems.
