多学科视角下羡余旅游资源转化路径研究

旅游资源羡余是旅游者预算约束、旅游资源空间集聚及其他相关因素导致的部分资源的闲置现象,具有普遍性、相对性和可变性,这些特征决定了旅游资源羡余现象研究的理论价值和现实意义,以及羡余旅游资源转化的必要性和可能性。在综合运用经济学、地理学、生态学理论对旅游资源羡余现象成因进行深入分析的基础上,提出了转化的基本思路与常用策略,主要包括资源管理协同化、产品开发差异化、市场定位细分化、形象策划创意化、交通连接便捷化。     

Necessary and Sufficient Condition for Nonsingular Fisher Information Matrix in ARMA and Fractional ARIMA Models

It is demonstrated that a necessary and sufficient condition for the Fisher information matrix of a causal and invertible ARMA to be nonsingular is that the model not be redundant; that is, the autoregressive and moving-average polynomials have no roots in common. This result is also extended to fractional ARIMA models.     

数据立方体压缩存储技术研究现状与展望

数据立方体的压缩存储是大型数据库中立方体优化计算的重要研究内容。介绍了数据立方体压缩存储技术的概念,并在分类总结当前立方体数据压缩技术及其代表方法的基础上,对这些技术进行了分析和比较,最后探讨了数据立方体压缩存储技术的发展方向。     

纳西东巴文中的简省和羡余

简省和羡余是文字发展过程中一个较为普遍的现象,纳西东巴文虽属较为原始的古文字系统,但同样存在这两种情况,本文拟把纳西东巴文中简省和羡余作一分类描述,初步归纳出导致纳西东巴文简省和羡余的特点和原因,为纳西东巴文及普通文字学的研究提供参考。     

On the optimal allocation of active redundancies in series system

This paper studies the allocations of two non identical active redundancies in series systems in terms of the reversed hazard rate order and hazard rate order, which generalizes some results built in Valdés and Zequeira (2003 Valdés, J. E., and R. I. Zequeira 2003. On the optimal allocation of an active redundancy in a two-component series system. Stat. Probab. Lett. 63:325–32.[Crossref], [Web of Science ®] , [Google Scholar], 2006 Valdés, J. E., and R. I. Zequeira 2006. On the optimal allocation of two active redundancies in a two-component series system. Oper. Res. Lett. 34:49–52.[Crossref], [Web of Science ®] , [Google Scholar]).     

2n值命题演算的 语义及其在大数据中的应用

本文的目标是建立2n值命题演算(2n-Valued Propositional Calculus,2nP)的语义,为大数据科学奠定逻辑基础.描述了2n值逻辑的真值形式、采用位结构刻画了联结词的功能,并建立了赋值映射;根据多值逻辑的特点,以数据冗余、key-value模型为例,直觉地讨论了2n值逻辑应用于大数据研究的有效性;初步分析了2nP语义与经典命题逻辑语义之间的关系,并展望了2nP在计算机科学、人工智能、信息技术等学科的应用前景.     

真实听力材料英语口语体特征分析

在日常生活中,英语口语体是英语语言最自然的表现形式,在各种社交场合占有较重的比例。英语口语体主要表现在口音、语调、冗余和语流音变等方面,它们共同构成了其显著的口语特征。对英语真实听力材料的口语体特征进行分析,有助于正确理解话语的目的。     

On the relevance of weaker instruments

ABSTRACT

We study the asymptotic properties of the standard GMM estimator when additional moment restrictions, weaker than the original ones, are available. We provide conditions under which these additional weaker restrictions improve the efficiency of the GMM estimator. To detect “spurious” identification that may come from invalid moments, we rely on the Hansen J-test that assesses the compatibility between existing restrictions and additional ones. Our simulations reveal that the J-test has good power properties and that its power increases with the weakness of the additional restrictions. Our theoretical characterization of the J-test provides some intuition for why that is.     

单片机应用系统的自动恢复技术

从软件的角度简要讨论了单片机系统在遭受干扰后，及时发现和拦截失去控制的程序流向并尽可以无扰动地恢复系统正常工作状态的各种方法和措施。