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951.
以美、法、英、德、加拿大等国为范例,对五种不同的欧美国家广播电视行政管理型态及其原则与职责作横向的比较研究,揭示它们作为国家广播电视行政管理模式的多样性,揭示其相同特征:均以宪法、法律为基础,在民主宪政框架内奉行“公共服务”的核心理念,保障公众利益在传媒领域的体现,以及独立行政、自治、多元主义、社会利益集团高度参与性等发展总趋势。  相似文献   
952.
提出了用系统分解法研究不等式的思路和方法,以实例方式介绍了这种方法的应用;提出了聚合集和聚合量级的概念.从而为量级研究提供了新视角和新课题;最后给出3个待解决的不等式问题.  相似文献   
953.
在广东理工职业学院和广东技术师范学院的大学生中进行的有关大学生社会主义核心价值体系教育现状的问卷调查显示,大学生总体上重视对社会主义核心价值体系的学习,基本上能够认同、赞成社会主义核心价值体系,只有极少数大学生存在错误思想和信仰危机,在个人价值观和道德判断上出现了迷茫和偏差;但大多数大学生对于社会主义核心价值体系的践行...  相似文献   
954.
该文根据国家权威档案文献,论述1860年汕头开埠始末的曲折过程;指出,汕头开埠是第二次鸦片战争清政府屈辱妥协外交路线的产物,是中华民族的屈辱史,是粤东门户被迫"开放"史,也是潮汕历史大走向的重要转折点。今人应以胡乔木《国史事典》的题词"在沉重的历史中,汲取奋进的力量"为警示,"知耻近于勇",爆发奋进之力,建设美好家园。  相似文献   
955.
高宗建炎四年五月,为抵御金人南侵,南宋在宋金边境设立了众多的藩镇——镇抚司.镇抚司的割据性很强,但镇抚司的设置并未导致南宋最终出现类似唐代藩镇尾大不掉的局面.绍兴五年四月,诸镇抚司尽罢.通过设置镇抚司,南宋王朝最终稳定了统治,其废罢同时,也是绍兴十一年收夺大将兵权前的一次成功预演.  相似文献   
956.
Radar cross section (RCS) of non-spherical raindrops is calculated by using the software CST based on finite integral method and compared with RCS of spherical raindrops. The revised factor of non-spherical raindrops is obtained. The radar reflectivity with precipitation change of four distribution models of M-P, Gamma, JD and JT combining the revised factor is gotten using trapezoidal integration. When the influence of non-spherical raindrops is considered, the accuracy of precipitation measurement of four distribution models can be separately improved 8.77%, 8.47%, 10.53% and 8.04% in the case of rain intensity is 100 mm/h.  相似文献   
957.
Arbitrary topological curve network has no restriction in topology structure,so it has more powerful representing ability in defining complex surfaces.A complex surface modeling system is presented based on arbitrary topological curve network and the improved combined subdivision method,its functions including creating and editing curve network,and generating and modifying curve network's interpolated surface.This modeling system can be used to the process of products'concept design,and its applications is ...  相似文献   
958.
File semantic has proven effective in optimizing large scale distributed file system. As a consequence of the elaborate and rich I/O interfaces between upper layer applications and file systems, file system can provide useful and insightful information about semantic. Hence, file semantic mining has become an increasingly important practice in both engineering and research community. Unfortunately, it is a challenge to exploit file semantic knowledge because a variety of factors could affect this information exploration process. Even worse, the challenges are exacerbated due to the intricate interdependency between these factors, and make it difficult to fully exploit the potentially important correlation among various semantic knowledges. This article proposes a file access correlation miming and evaluation reference (FARMER) model, where file is treated as a multivariate vector space, and each item within the vector corresponds a separate factor of the given file. The selection of factor depends on the application, examples of factors are file path, creator and executing program. If one particular factor occurs in both files, its value is non-zero. It is clear that the extent of inter-file relationships can be measured based on the likeness of their factor values in the semantic vectors. Benefit from this model, FARMER represents files as structured vectors of identifiers, and basic vector operations can be leveraged to quantify file correlation between two file vectors. FARMER model leverages linear regression model to estimate the strength of the relationship between file correlation and a set of influencing factors so that the “bad knowledge” can be filtered out. To demonstrate the ability of new FARMER model, FARMER is incorporated into a real large-scale object-based storage system as a case study to dynamically infer file correlations. In addition FARMER-enabled optimize service for metadata prefetching algorithm and object data layout algorithm is implemented. Experimental results show that is FARMER-enabled prefetching algorithm is shown to reduce the metadata operations latency by approximately 30%–40% when compared to a state-of-the-art metadata prefetching algorithm and a commonly used replacement policy.  相似文献   
959.
Amorphous InGaZnO (a-IGZO) films were deposited on the corning eagle XG (EXG) glass substrates using magnetron sputtering method. The structure, surface morphology, electrical and optical properties of these films were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), semiconductor parameter analyzer and spectrophotometry, respectively. The influence of oxygen flow on the electrical properties of IGZO thin films was studied, showing that increasing oxygen flow changes the resistivity with six orders of magnitude. The contact resistance of ITO/IGZO is 7.35×10−2 Ω·cm2, which suggests that a good ohmic contact exists between In2O3: Sn (ITO) and IGZO film.  相似文献   
960.
This work investigated the microwave dielectric properties of A-site substitution by rare earth La3+in(Pb0.5Ca0.5)(Fe0.5Ta0.5)O3(PCFT) system.A single perovskite phase was obtained only when the doping content was 2%.Suitable La3+ doping improved microwave dielectric performances.Excessive La3+doping caused the formation of secondary phase,which resulted in the decreasing of permittivity εrand quality factor Qfvalues.Especially,when the doping content is 2%-5%,permittivity εrwas above 75 and Qfvalues were 6...  相似文献   
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