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41.
王安忆的创作风格跟随时代的变化而发生变化,将王安忆作品与社会文化背景相结合,从“雯雯系列”、寻根文学、先锋文学、女性文学、城市文学五个主题的变化中,既体现出对潮流的追随,又执着地坚守着自己的本心。她的创作不仅是自我的突破,而且真实地反映了时代的变迁。  相似文献   
42.
传统辐射源信号识别方法往往需要人工提取特征,不仅对专业知识要求较高,而且人为选择的特征不能够保证适用于大多数类型信号的识别,识别精度和识别速度也不能兼顾。针对上述问题,将语音处理领域常用的深度学习模型——卷积长短时深度神经网络(convolutional long short-term deep neural network, CLDNN)引入到辐射源信号的识别中,并将该模型中的长短时记忆层改为双向门控循环单元层。模型的输入为原始时间序列数据,特征提取和分类识别过程均在网络中进行,避免了人工选择特征的不完备性。实验结果表明,所提模型在低信噪比情况下也能够有效识别信号类型,同时与其他模型相比,实现了识别精度和识别速度之间的平衡。  相似文献   
43.
 从授权专利的角度,综合专利的数量和专利的质量,采用时间序列分析方法,还原了中国专利发展走过的“从无到有的发展之路,从慢到快的升级之路,从弱到强的转型之路”。1949年新中国成立后,尚无相关的专利法规法律,更无从谈起专利数量。直到1984年,《中华人民共和国专利法》正式推出,表明中国的专利制度初步形成。1985年中国有了正式的授权专利,其数量为54项,2000年授权量突破万项,到2009年授权量超过10万项,再到2012年授权量突破20万项,现在中国专利的年授权量已经突破了40万项。从1989-2008年的20年,中国大陆的专利比例常年低于50%,其专利主导强度也持续低于1,甚至在1999-2003间,专利主导强度仅有0.51。从2009年始,中国大陆的专利比例开始持续增长,且在2014-2018年间上升到75.48%,其专利主导强度也增长到了3.08。  相似文献   
44.
众所周知,在《数学分析》中会遇到连续函数的一个重要定理,即根的存在定理,此定理对方程根的存在性判别起着重要作用.将这方面已有的定理进行推广,并用例题说明其应用情况.  相似文献   
45.
 厨余垃圾已成为法定分类处理的垃圾组分。农村厨余垃圾产生点分散,适合就近处理和产物就地利用,实现有机质还田和植物养分循环。因此,农村厨余垃圾的处理方式区别于城市。中国通过实践已形成了一系列特征性的农村厨余垃圾处理技术。采用实地调查的方法,结合技术原理,分析了这些处理技术存在的原料预处理、转化条件和产物利用问题,提出了针对性改进建议。  相似文献   
46.
This paper criticizes the traditional philosophical account of the quantization of gauge theories and offers an alternative. On the received view, gauge theories resist quantization because they feature distinct mathematical representatives of the same physical state of affairs. This resistance is overcome by a sequence of ad hoc modifications, justified in part by reference to semiclassical electrodynamics. Among other things, these modifications introduce ”ghosts”: particles with unphysical properties which do not appear in asymptotic states and which are said to be purely a notational convenience. I argue that this sequence of modifications is unjustified and inadequate, making it a poor basis for the interpretation of ghosts. I then argue that gauge theories can be quantized by the same method as any other theory. On this account, ghosts are not purely notation: they are coordinates on the classical configuration space of the theory—specifically, on its gauge structure. This interpretation does not fall prey to the standard philosophical arguments against the significance of ghosts, due to Weingard. Weingard’s argumentative strategy, properly applied, in fact tells in favor of ghosts’ physical significance.  相似文献   
47.
Taking a cue from remarks Thomas Kuhn makes in 1990 about the historical turn in philosophy of science, I examine the history of history and philosophy of science within parts of the British philosophical context in the 1950s and early 1960s. During this time, ordinary language philosophy's influence was at its peak. I argue that the ordinary language philosophers' methodological recommendation to analyze actual linguistic practice influences several prominent criticisms of the deductive-nomological model of scientific explanation and that these criticisms relate to the historical turn in philosophy of science. To show these connections, I primarily examine the work of Stephen Toulmin, who taught at Oxford from 1949 to 1954, and Michael Scriven, who completed a dissertation on explanation under Gilbert Ryle and R.B. Braithwaite in 1956. I also consider Mary Hesse's appeal to an ordinary language-influenced account of meaning in her account of the role of models and analogies in scientific reasoning, and W.H. Watson's Wittgensteinian philosophy of science, an early influence on Toulmin. I think there are two upshots to my historical sketch. First, it fills out details of the move away from logical positivism to more historical- and practice-focused philosophies of science. Second, questions about linguistic meaning and the proper targets and aims of philosophical analysis are part and parcel of the historical turn, as well as its reception. Looking at the philosophical background during which so-called linguistic philosophers also had a hand in bringing these questions to prominence helps us understand why.  相似文献   
48.
Public participation in scientific research has gained prominence in many scientific fields, but the theory of participatory research is still limited. In this paper, we suggest that the divergence of values and goals between academic researchers and public participants in research is key to analyzing the different forms this research takes. We examine two existing characterizations of participatory research: one in terms of public participants' role in the research, the other in terms of the virtues of the research. In our view, each of these captures an important feature of participatory research but is, on its own, limited in what features it takes into account. We introduce an expanded conception of norms of collaboration that extends to both academic researchers and public participants. We suggest that satisfying these norms requires consideration of the two groups' possibly divergent values and goals, and that a broad characterization of participatory research that starts from participants' values and goals can motivate both public participants’ role in the research and the virtues of the research. The resulting framework clarifies the similarities and differences among participatory projects and can help guide the responsible design of such projects.  相似文献   
49.
基于气象数据、MODIS遥感影像数据和NCEP再分析资料, 利用HYSPLIT模型模拟2000—2019年毛乌素沙地上空不同海拔高度(500, 1000和1500 m)各季节沙尘暴的前向轨迹, 并与遥感影像识别出的沙尘信息进行比较, 识别毛乌素沙地沙尘暴的影响范围。结果显示: 1) 在过去的20年中, 共有143个沙尘暴月和387个沙尘暴日, 并且 2004 年以来, 毛乌素沙地发生沙尘暴的频率逐渐降低; 2) 季节性气候条件对毛乌素沙地沙尘暴的移动路径有很大的影响, 春季沙尘暴发生频率较高, 秋季发生频率最低; 3) 受毛乌素沙地沙尘暴影响的国内地区主要包括陕西省北部、山西省北部、河北省北部和中部、山东省北部和中部、北京市、天津市、内蒙古自治区东部以及东北三省, 国外受影响的地区有朝鲜、日本北部以及俄罗斯与我国交界处, 受影响的海域有渤海、黄海北部和日本海西北部。遥感影像与HYSPLIT模型的比较提供了一种对沙尘运输、扩散和沉积过程进行验证和加深了解的有效工具, 研究结果可以为防灾减灾决策及沙源地治理提供科学的参考依据。  相似文献   
50.
Despite remarkable efforts, it remains notoriously difficult to equip quantum theory with a coherent ontology. Hence, Healey (2017, 12) has recently suggested that “quantum theory has no physical ontology and states no facts about physical objects or events”, and Fuchs et al. (2014, 752) similarly hold that “quantum mechanics itself does not deal directly with the objective world”. While intriguing, these positions either raise the question of how talk of ‘physical reality’ can even remain meaningful, or they must ultimately embrace a hidden variables-view, in tension with their original project. I here offer a neo-Kantian alternative. In particular, I will show how constitutive elements in the sense of Reichenbach (1920) and Friedman (1999, 2001) can be identified within quantum theory, through considerations of symmetries that allow the constitution of a ‘quantum reality’, without invoking any notion of a radically mind-independent reality. The resulting conception will inherit elements from pragmatist and ‘QBist’ approaches, but also differ from them in crucial respects. Furthermore, going beyond the Friedmanian program, I will show how non-fundamental and approximate symmetries can be relevant for identifying constitutive principles.  相似文献   
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