Header error control schemes for coping with upstream channel noise in the HFC network

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.     

我国国防知识产权的十大特点

本文从国防知识产权客体发明创造或创作者、取得或被确认程序、形成或维持费用、种类客体所处状态、知识产权权利人、产业化形成产品、功能表现、获得或知悉渠道、利用主体及管理和保护等10个方面分析了我国国防知识产权的特点与应受到的启示。     

期刊全流程数字出版探索与实践 ——以《光学学报》为例

随着互联网技术的不断发展,科技期刊面临重要转型。如何推动科技期刊数字化出版建设、媒体融合发展,快速提升期刊的影响力成为一个重要课题。本文以融媒体技术手段为依托,详细总结了期刊在选题策划、稿件处理、多模式出版、融媒体服务等方面的数字化建设经验,以供其他科技期刊学习和借鉴。     

国际著名检索系统收录我国高校学报的情况分析及应对策略

通过对美国SCI、Ei、MEDLINE、CA 等4种国际著名检索系统收录评价体系及我国高校学报被这4种国际著名检索系统收录情况的分析,认为我国高校学报应从提高学术质量、提升刊物的国际化程度、强化期刊的编排出版规范、缩短出版周期、注意英文写作规范、重视引文分析数据、加强对国际检索机构进行有针对性的宣传并与之动态联系等几方面入手,方能提高被国际著名检索系统收录的可能性.     

Novel distribution pattern of fibrinolytic components in rabbit tissues extract： a preliminary study

Objective: The purpose of this work was to investigate the distribution pattern of fibrinolytic factors and their inhibitors in rabbit tissues. Methods: The components of the fibrinolytic system in extracts from a variety of rabbit tissues, including tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1), plasminogen (Plg), plasmin (Pl) and α2 plasmin inhibitor (α2PI), were determined by colorimetric assay. Results: The tissue extracts in renal, small intestine, lung, brain and spleen demonstrated strong fibrinolytic function, in which high activity of tPA, Plg and Pl was manifested; whereas in skeletal muscle, tongue and stomach, higher activity of PAI-1 and α2PI showed obviously. Also excellent linear correlations were found between levels of tPA and PAI-1, Pl and α2PI, Plg and Pl. In related tissues, renal cortex and renal marrow showed distinctly higher activity of tPA and lower activity of PAI-1, with the levels of Plg and Pl in renal cortex being higher than those in renal marrow, where the α2PI level was higher than that in renal cortex. Similarly, the levels of tPA, Plg and Pl in small intestine were higher than those in large intestine, but with respect to PAI-1 and α2PI, the matter was reverse. In addition, the fibrinolytic activity in muscle tissue was lower, however, the levels of tPA, Plg, and Pl in cardiac muscle were obviously higher than those in skeletal muscles, and the levels of PAI-1 and α2PI were significantly lower than those in skeletal muscle. Conclusion: Our data demonstrate that a remarkable difference of the fibrinolytic patterns exists in rabbit tissues, which has probable profound significance in understanding the relationship between the function of haemostasis or thrombosis and the physiologic function in tissues.     

幼儿换班引发的心理问题及其千预策略

由于幼儿父母工作调动、家庭地址变迁或幼儿园班级调整等原因,幼儿换班已经成为一种常见的现象.换班包括幼儿园内换班和幼儿园间换班.其中,幼儿园内换班主要是指在幼儿园内进行的班级调整,部分幼儿从原来的班级调入新的班级,幼儿园间换班是指幼儿离开原来的幼儿园进入新幼儿园的新班级,本文主要论述的是幼儿园内换班(简称"换班",下同).     

基于上市公司年报分析的图书馆与数据库商博弈思路研究

[目的 /意义]针对图书馆数字资源采购谈判中面临的不合理合约、产品高定价、高涨幅等业内难题,引入上市公司年报分析法来寻求新的博弈思路。[方法 /过程]构建产业链分析、收入-利润指标、竞争力因素分析框架,以Elsevier、中国知网、Clarivate三家数据库商为分析案例,发现竞争力、利润、续订率是数据库商最关注的3个方面,认为图书馆在与数据库商的博弈中同时存在主动性和被动性两方面,在过去的谈判思路中对营业成本与涨价幅度、利润率和参考对象、开放获取与社会责任的认知有一定偏差。[结果 /结论 ]图书馆在开放信息生态下将面临新一轮的资金压力和业务重塑,应从探索零和博弈、重复博弈的竞争性策略,资金适度向国内学术出版商倾斜,寻求媒体关注、法律支持,深化数字出版产品价格相关研究方面应对新的挑战。     

浅析邓小平马克思主义观的理论特色

邓小平的马克思主义观是在实践中形成的,具有实事求是、务实管用、与时俱进的理论特色。邓小平用发展着的马克思主义指导新的实践,指引我们党高擎理论创新的大旗,继承和发扬科学的马克思主义观,不断开拓马克思主义中国化、时代化和大众化的新境界。     

中国股指期货推出对A股波动影响分析

基于发展较成熟的恒生指数日收益率波动情况,引入股指期货推出前后的虚拟变量,建立ARCH和GARCH模型,检验股指期货推出对股指波动的影响,有利于揭示股指期货的波动性规律,降低市场系统性风险。实证研究结果表明,GARCH（2,1）模型拟合效果最佳;股指期货的推出,不但没有增加股指的波动性,反而对其波动性有所降低,但这种影响从数值来看非常小。     

民族高校细胞生物学实验教学改革探索

为了进一步培养民族高校学生的实验技能,在细胞生物学实验课程教学中,实验课教学小组通过不断改革教学方法,适应新的教学体系,及时调整实验教学内容和形式,以及建立完善的成绩评定体系,把好教学质量关,充分发掘学生的潜能,增强学生学习的自信心和兴趣,从而达到提高学生实验技能的目的.通过对近4年的细胞生物学实验成绩的分析,结果显示,实验对绝大多数学生在提高专业技能、培养独立工作能力、提高分析问题和解决问题能力、提高自主学习意识和能力、增强团队协作意识等方面有很大帮助.