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1.
传统粒子滤波(PF)直接采用状态转移先验分布作为重要性密度函数来近似后验概率密度函数,使得后验概率密度函数未包含量测信息。针对此问题,提出了一种改进高阶容积粒子滤波(CPF)的系统状态估计算法。算法采用七阶正交容积卡尔曼滤波(7th-CQKF)对PF的粒子进行传递,使得先验分布更新阶段融入最新量测信息;通过7th-CQKF设计重要性密度函数,提高对状态后验概率密度的逼近程度;通过反比例函数计算粒子权重,突出大噪声粒子与小噪声粒子权重差别,提高粒子有效性。仿真结果表明,改进高阶容积粒子滤波的估计精度高于容积粒子滤波(CPF)。  相似文献   
2.
The growing body of literature on “accessible tourism” lacks a critical scholarly debate around its specific language use and nomenclatures. To fill this gap, this paper provides a first examination of language. Language provides a unique capability to resist, strengthen and reframe identities of individuals and groups, yet can also reinforce, weaken and perpetuate dominant worldviews of disability. A content analysis examined previous accessible tourism literature with results illustrating that diversity exists amongst the varying terminologies adopted by scholars. Terms were employed loosely, inconsistently and interchangeably, euphemistically with erroneous understandings and nuances. The paper concludes with critical discussion about the power of researchers to (re) produce oppression through language that maligns and misrepresents, or to (re) conceptualise and (re) construct the world we live in with liberating language that facilitates positive social change.  相似文献   
3.
ABSTRACT

This research introduces online travel photos published on social media platforms as a complementary data resource to examine the behavior and experience of museum visitors. The practical value of online travel photos is demonstrated through a case study of popular Hong Kong museums, particularly by using the photo content and metadata available from the Flickr platform. The proposed approach is a generic method for understanding museum visitor behavior and preferences, and supports museum practitioners in developing improved products for visitors. The case study findings are particularly beneficial for tourism managers, especially those in Hong Kong, in promoting and attracting tourists to visit local museums.  相似文献   
4.
刘会省  王彦明  任文秀 《现代食品》2021,(6):127-130,141
燕麦营养丰富,蛋白质、脂质和膳食纤维的含量在谷类作物中含量较高,并且含有生物碱等功效成分,具有良好的营养和保健功能。本文综述了燕麦蛋白质、淀粉、脂质、膳食纤维和生物碱的提取和纯化方法,介绍了其在保健食品、特医食品和化妆品行业的应用,为燕麦深加工产业提供参考。  相似文献   
5.
We commemorate the 50th anniversary of Ball and Brown [1968] by chronicling its impact on capital market research in accounting. We trace the evolution of various research paths that post–Ball and Brown [1968] researchers took as they sought to build on the foundation laid by Ball and Brown [1968] to create a body of research on the usefulness, timeliness, and other properties of accounting numbers. We discuss how those paths often link back to the groundwork laid and questions originally posed in Ball and Brown [1968].  相似文献   
6.
Brands are constantly competing for user attention on Facebook and are trying to encourage fans to share, click ‘like’, and comment their posts. Yet, it remains unclear what content strategies are successful at encouraging those behaviors. Noting that the effectiveness of brand content strategies still remains an uncharted research area, this study adopts a discovery-oriented approach and employs workshops, quantitative content analysis, and episodic interviews, to link desired user responses (namely clicks share, ‘like’, and comment) to brand content strategies. This study reveals that customer-centric content strategies are the most effective at encouraging user responses. Managers can use provided recommendations to engage their customers by adopting content strategies that result in desired behavioral reactions.  相似文献   
7.
本文对西方现代公司股利政策方面的理论和实证研究进行了一个综合性的回顾和分析。其中包括主流的股利行为模型、股利的信息内涵、代理成本、追随者效应,也包括国内研究中较少涉及的债务约束、声誉学说、成长机会和交易成本问题,以期对国内相对落后的股利政策研究和随意性较强的股利政策制定带来一定的借鉴意义。  相似文献   
8.
新《保险法》第19条的法理基础源于格式条款的内容控制原则,内容上对我国《合同法》和台湾地区保险法有关规定有所借鉴。其立法意旨是依据诚实信用和公平正义原则,对不利于被保险人的不公平条款进行规制。保险条款效力认定,包括合法性判断和合理性判断。合法性判断要着重分析保险条款免除的义务或排除的权利所指向之法律规定为任意性规范的情形;合理性判断重在具体情形下的利益平衡。鉴于现阶段保险条款存在较多公平性问题,第19条的规范意义非常重大;为避免矫枉过正,其适用应当科学审慎,尤其要尊重保险合同特性,合理运用司法裁量。  相似文献   
9.
教学方法与教学手段的改革是高校教学改革的重点之一。高职高专院校的数学教学应采取多种形式的教学方法,比如启发式教学法、形象解析法等等。只有恰当和正确地设计教学方法和教学手段.才能达到高质量的教学效果,进而针对性地提高学生运用数学思维解决实际问题的能力。  相似文献   
10.
We examine the two traditions of content analysis: the first in which one substitutes words of a text with categories, and the second in which one looks for clusters of words that may refer to a theme. In the first tradition, preexisting dictionary categories give meaning to the words; in the second, meaning comes after the fact. Preexisting dictionary categories (the substitution model) are calibrated instruments applied within experimental designs that leave no space for doubt; meanwhile, the ability of the correlational model to conjure up complex themes from fragments of a text yields no unique solution. These differences have bearings on the production of new social knowledge. We expound on the epistemological foundations of the two traditions of interpretation and draw from them decision rules upon which one may rely for choosing among appropriate content-analytic tactics. Two reasons make this essay timely and critical: (1) the increasing variety of new content-analyticsoftware for particular purposes and (2) the almost exclusive focusing on software and technology at the expense of adjusting the choice of the software to the nature of the text. Two studies, one in historiometry, the other in autobiography, illustrate the liabilities and benefits of the two models of content analysis.  相似文献   
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