增长极理论在区域旅游合作中的应用——宁镇扬区域旅游合作发展模式探讨

基于增长极理论对宁镇扬区域旅游发展的现状进行了SWOT分析,在对增长极理论深入分析基础上,提出宏观与微观相结合的旅游合作发展模式,即:三层次相结合的合作模式.     

Situating the wildlife spectacle: ecofeminism,representation, and polar bear tourism

This paper presents a critical investigation of power relations circulating in promotional materials associated with polar bear tourism in Churchill, Manitoba, Canada. Drawing on precepts of ecofeminism, critical discourse analysis, and the content of cultural texts (websites, souvenirs) produced by tourism operators, businesses, and crown corporations, the study interprets how representations of polar bears re-inscribe regimes of truth that marginalize non-human animal others and are complicit with patriarchal ideologies. Focus in our analysis is placed first, on illustrating the portrayal of “performing spectacle bears” – a socially constructed subjectivity designed to serve the desires of wildlife tourism producers and consumers – and, second, on diagnosing the privileged discourses that work to maintain and normalize this construction, along with the interspecies dynamics they support. In effect, the paper sheds light on the complex and recurrent effects of anthropocentric and instrumentalist orientations in tourism, including their contingency upon masculine systems of value and rationality. The paper also points out the potential of ecofeminist ethics of care for enhancing interspecies relationships in sustainable tourism.     

“三驾马车”驱动碳排放效应及变动研究

基于最终需求的视角,构建扩展的(进口)竞争型投入产出模型,采用改进的两极分解方法,从经济整体及行业部门层面对最终需求以及消费、投资、出口等各类需求的碳排放驱动效应进行分解。结果表明: (1) 1992-2012年间,最终需求驱动碳排放净增加66.19 亿吨,其中规模效应及中间结构效应驱动碳排放增加73.68和44.76亿吨,技术效应减少碳排放51.87亿吨。(2) 从"三驾马车"碳排放"贡献"及变动来看,消费排放份额持续下降,投资、出口排放占比不断上升;(3)从各类需求自身驱动效应及部门分布特征来看,"三驾马车"驱动碳排放存在巨大差异:消费驱动碳排放主要集中于农业及服务业,且以规模效应为主;投资、出口驱动碳排放主要集中于工业,且以规模效应及中间结构效应为主。     

系统极化码的置信传播译码性能分析

置信传播（BP）算法可以为系统极化码提供软信息作为判决依据,也可以为系统极化码在级联迭代译码中提供交换软信息。在详细描述基于信道极化结构的置信传播算法基础上,比较了系统极化码在软信息判决方法和极化编码判决方法下错误率性能的差异。仿真结果表明,软信息判决方法可以提高系统极化码的误比特率,在高信噪比下误帧率方面也略有提高。     

Construction of Exact Simultaneous Confidence Bands for a Simple Linear Regression Model

A simultaneous confidence band provides a variety of inferences on the unknown components of a regression model. There are several recent papers using confidence bands for various inferential purposes; see for example, Sun et al. (1999) , Spurrier (1999) , Al‐Saidy et al. (2003) , Liu et al. (2004) , Bhargava & Spurrier (2004) , Piegorsch et al. (2005) and Liu et al. (2007) . Construction of simultaneous confidence bands for a simple linear regression model has a rich history, going back to the work of Working & Hotelling (1929) . The purpose of this article is to consolidate the disparate modern literature on simultaneous confidence bands in linear regression, and to provide expressions for the construction of exact 1 ?α level simultaneous confidence bands for a simple linear regression model of either one‐sided or two‐sided form. We center attention on the three most recognized shapes: hyperbolic, two‐segment, and three‐segment (which is also referred to as a trapezoidal shape and includes a constant‐width band as a special case). Some of these expressions have already appeared in the statistics literature, and some are newly derived in this article. The derivations typically involve a standard bivariate t random vector and its polar coordinate transformation.     

Lack of commitment to future privatization policies may lead to worst welfare outcome

We investigate the welfare consequences of a lack of commitment to future privatization policies. The government implements a privatization policy after the competition structure is determined by the entry of private firms. We find that in an equilibrium, the government fully privatizes (nationalizes) a public firm if private firms expect that the government fully privatizes (nationalizes) the public firm. This is because an increase in the number of firms entering a market increases the government's incentive to privatize the public firm, which mitigates future competition and stimulates entries. The full-privatization equilibrium is the worst privatization policy among all possible (either equilibrium or non-equilibrium) privatization policies for welfare because it causes excessive market entry of private firms. Partial commitment of a minimal public ownership share may mitigate this problem.     

一种低迭代次数的极化码置信传播译码算法

针对置信传播（Belief Propagation,BP）译码算法在迭代次数较多时吞吐量和译码时延性能提升受限的问题,提出了一种低迭代次数的极化码BP译码算法,通过采用比特翻转和子信道冻结的方式,降低译码过程中的迭代次数。仿真结果表明,相对于传统极化码BP译码算法（设置最大迭代次数为40次）,所提算法在信噪比为3 dB时可将平均迭代次数减少约53%,处理单元平均计算次数减少约68%。该算法所带来的低时延和低功耗效益可运用在对功耗要求较高的大规模机器类型通信,以及对时延要求较高的超可靠低延迟通信等5G场景下的极化码译码中。     

Interval bidding in a distribution elicitation format

Interval bidding allows people to report a range of values for a non-market good. Herein, we allow people to choose their distribution over this range endogenously. We consider a multiplicative error model explaining the willingness to pay (WTP) which is estimated using a feasible generalized least squares estimator. We apply our framework to a representative sample of the French population who were asked about the valuation of a bear conservation programme. We find that most participants prefer stating their WTP as a range rather than a point, but the shape of the distribution greatly varies across people. Our results support the use of the interval bidding with endogenous distribution approach in valuation studies.     

新疆3种特色食品油炸过程中油脂废弃指标变化规律研究

本研究分别以大豆油、棉籽油为煎炸油,在180℃条件下对3种新疆特色食品馓子、牛肉丸、夹沙进行油炸.研究大豆油、棉籽油在煎炸过程中废弃指标酸价和总极性组分的变化规律.结果表明,随着油炸时间的延长,酸价和总极性组分均呈逐渐上升趋势;根据GB 2716—2018规定的煎炸油废弃指标限定值(总极性组分≥27％,酸价≥5 mg KOH/g),大豆油油炸馓子、牛肉丸和夹沙过程中废弃时间分别为56～64 h、64～72 h和48～56 h,棉籽油油炸馓子、牛肉丸和夹沙过程中废弃时间均为48～56 h;大豆油的煎炸稳定性强于棉籽油,更适合应用于上述3种食品的油炸生产.本研究为新疆特色食品油炸过程中煎炸油品质及废弃点判别提供了理论依据.     

浅谈如何做好施工测量工作

测量工作是基层施工单位一项重要基础工作,文章介绍了路基路面及桥梁构造物等方面的测量放样工作中常用的方法可供测量人员参考。