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61.
比较教育研究的基本范式述评 总被引:5,自引:0,他引:5
本文根据历史线索对比较教育研究领域中的三种范式:科学主义的研究范式、批判理论的研究范式和解释学的研究范式,进行了大致的厘定和评价,试图展示该领域理论形态和研究策略的整体景观。同时,就各自理论话语所处的特定语境作简单的分析,并倡导各自间不应是相互对峙与攻讦,而是要彼此间抱宽容和理解态度,不是苛求于整合而是要寻求互补。 相似文献
62.
The Hybrid Fiber-Coax (HFC) network is being paid close attention to in recent years as a bi-directional broadband access
network. To achieve seamless connection with the backbone network, and Asynchronous Transfer Mode (ATM) Network Network Interface
(NNI) cell format is used as the basic transmission packet unit in the HFC system. As the transmission condition of the HFC
system’s upstream channel is bad, two improved header error control (HEC) schemes, i. e. the improved HEC and the cell interleaving
technique, are employed to guarantee the packet integrity. Theoretical analysis of the results showed that the improved HEC
and the cell interleaving technique are applicable to isolated random errors and burst errors, respectively. 相似文献
63.
Dazhong Ma Qiuye Sun Xiangpeng Xie Xiaoyu Li 《Journal of The Franklin Institute》2019,356(3):1225-1246
The power sharing of AC/DC micro-grids is researched in this paper. The proposed strategy mainly include two parts: the primary power event triggering control with secondary control and an adaptive quasi sliding mode voltage control in inner-loop. Firstly, a event triggering power sharing control (ETPSC) based on droop curve is developed to regulate the voltage and frequency of AC and voltage of DC with the aim of the proportional power sharing between AC and DC micro-grids. The triggered threshold of ETPSC can be chosen to decide the transmitted power between AC and DC micro-grids. When the difference power between AC and DC micro-grids is less than the triggered threshold of power flow, there is no power sharing between AC and DC micro-grids, which can less the number of switching the power flow direction and the transmitted line power loss. The ETPSC has a great robust for the disturbances of load and improve the stability of the system. An adaptive quasi-sliding-mode control,which is implemented easily and flexibly with small computational burden and only based on input/output (I/O) measurement data but not the model any more, is used to control voltage in inner-loop. The effectiveness of the proposed control schemes is demonstrated by some numerical simulations and experimental results. 相似文献
64.
中医认为原发性坐骨神经痛属于痹症范围,因风寒邪入侵,局部气滞血瘀,经络闭阻所致,本文就近年来坐内神经痛的治疗方法作一探讨。 相似文献
65.
笔者于1997~2000年间运用隔姜灸配合超短波,治疗急性细菌性痢疾31例,取得了较满意的疗效,现报告如下: 相似文献
66.
本文通过对超高层框筒结构-上海浦东新资大厦进行分析,着重介绍了超高层结构预应力设计中一些需要特珠注意的因素,同时针对超高层结构在预应力施工中的一些特点,提出了施工中一些特殊要求.本文对从事高层预应力结构设计及施工的人员有一定的借鉴作用. 相似文献
67.
本文在分析图书馆文化创意产品合作开发现状的基础上,以山东省图书馆首届文化创意产品设计大赛为契机,介绍了山东省试点图书馆+高校合作开发文化创意产品的情况,构建图书馆+高校合作开发文化创意产品模式化流程,并提出文创开发需要限定主题、创意空间服务文创、争取政策性激励以支持文创合作三点优化措施。 相似文献
68.
Potential growth of two widely-grown hybrid rice varieties in the Jinhua district of Zhejiang Province, Shanyou63 for mid-rice and Xieyou46 for late rice, was simulated using a crop growth model of WOFOST. Parameters of the rice growth in WOFOST were calibrated through field experiments from 1999 to 2002 in Jinhua. The potential yield simulated with WOFOST was about 12 t/ha for Shanyou63 and 10 t/ha for Xieyou46, which are in good agreement with the highest recorded yield obtained in this area. Under farmers practice, current yield is about 7.5 t/ha for Shanyou63 and 6.5 t/ha for Xieyou46. There is a gap between the actual rice yield and the potential yield for these two hybrid rice varieties grown in this area. The attainable target yields were set to 70% to 75% of their potential yields for the two varieties. A recently developed software "Nutrient Decision Support System (NuDSS)" for irrigated rice was used to optimize nutrient management for these two rice varieties. According to NuDSS, the optimal fertilizer N requirement for the target yields was about 150 kg/ha for Shanyou63 and about 120 kg/ha for Xieyou46, which were only about 70% of the fertilizer N application under current farmers' practice. Comparing with farmers' practice, there is great potential to increase actual rice yields and to reduce fertilizer N use rates by improving rice crop management practice in Jinhua. 相似文献
69.
通过对多媒体教学设施维护管理方法的总结,把国际上广泛应用的八项质量管理原则引入实际工作中,搭建了一个新的维护管理模式.基于八项质量管理原则,设计了"管理职责"、"资源管理"、"监测检查"和"分析改进"4个过程组成的多媒体教学设施质保体系过程模式.给出了一个多媒体教学设施质量保障管理方案,初步建立起多媒体教学设施维护管理质保体系. 相似文献
70.
建立了微波辅助提取、HPLC-ICP-MS联用分析中成药中二价汞和甲基汞的方法。分别比较了提取液中盐酸和L-半胱氨酸含量、提取温度和提取时间对提取结果的影响,得到了微波辅助提取的最优条件:体积分数为1%的盐酸10mL和质量分数为5%的L-半胱氨酸1mL作为提取液,控温70℃,微波辅助提取1h。该方法测得的二价汞和甲基汞的精密度分别为1.7%和4.4%,加标回收率分别为80.7%~99.5%和93.7%~95.8%。并应用该方法分析测定了20种、共49批次的含朱砂的中成药中可溶性汞的形态。 相似文献