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101.
针对机载三维音频应用的实时性需求,提出了一种基于单耳相对头相关传递函数和改进型混响模型的机载三维音频快速实现方法,在较传统实现方式性能无明显下降的情况下降低了80%的计算量。对提出的算法在F-16战斗机模拟强噪声环境下进行相关主观试听实验,同时在某型飞机音频系统中实验验证。实验结果表明,所提方法在实时处理3路三维音频时,三维音频方位分辨精度在5°以内,可满足实际机载平台使用需求。  相似文献   
102.
The notion of ‘students as customers’ continues to be prominent, yet is insufficiently explored, especially from the standpoint of various stakeholders. To address this inadequacy, the present study employs a multigroup analysis of the service profit chain (SPC) model in higher education (HE). Its purpose is to examine the complete SPC model regarding stakeholder perceptions in order to inform its validation and implementation. A cross-sectional survey was employed in order to enable multigroup comparison of a comprehensive research model on subsamples of employees and students by means of structural equation modeling (SEM). Results provide support for the proposed SPC model within the sample of vocational colleges. Besides strongly linked constructs (quality–satisfaction–loyalty), some notable weaknesses (cracked ‘satisfaction mirror’) are found. Multigroup analysis also indicates some important differences between employees and students. Implications are provided for strategic service management in HE, which should acknowledge the differences among stakeholder perceptions.  相似文献   
103.
This paper examines relationships between crop insurance and input technology decisions among Chilean wheat farmers. Using nationwide farm‐level data, a bivariate probit model is estimated. We investigate the extent to which the adoption of production input technologies is associated with farmers’ participation in the insurance program. We find that relationships between insurance and technology decisions are significant only for family farmers. In particular, there is a negative relationship between participation in the insurance program and the adoption of modern irrigation. Interpretations based on the role of input technologies on insurance adoption and adverse selection behaviours are discussed.  相似文献   
104.
Business model innovation is one of the firm’s most important strategic decisions. Top management team (TMT), as the critical decision-makers, has essential influence upon such decisions. However, the role of TMT diversity in shaping the performance of business model innovation is less explored in the literature. Based on a sample dataset of 906 observations of small and medium enterprises from China Startups Stock Market during the period of 2009–2011, we find that TMT diversity exhibits a significant threshold effect on the relationship between business model innovation (in terms of novelty-centred and efficiency-centred business model) and firm performance. More specifically, when TMT functional diversity arrives at a certain level, the positive relationship between novelty-centred business model and firm performance becomes more pronounced. On the other hand, the positive relationship between efficiency-centred business model innovation and firm performance will be more significant when TMT tenure diversity increases to a certain level.  相似文献   
105.
We use several U.S. and euro‐area surveys of professional forecasters to estimate a dynamic factor model of inflation featuring time‐varying uncertainty. We obtain survey‐consistent distributions of future inflation at any horizon, both in the U.S. and the euro area. Equipped with this model, we propose a novel measure of the anchoring of inflation expectations that accounts for inflation uncertainty. Our results suggest that following the Great Recession, inflation anchoring improved in the United States, while mild de‐anchoring occurred in the euro area. As of our sample end, both areas appear to be almost equally anchored.  相似文献   
106.
王勉  黄颖  杨颖 《科技和产业》2019,19(4):92-98
互联网经济快速发展,基于互联网平台的企业创新行为具有鲜明的特色。纵向研究了三家企业的创新过程,发现互联网环境下,企业商业模式创新有三个特点:以客户为中心的战略准则,价值创造由企业转向客户;企业打破边界,加强合作伙伴之间的协同和柔性,大幅提高创新效率;企业提高管理不确定的能力,领导者、企业文化、管理模式帮助企业应对不确定性。同时,提出当前创新模式存在核心技术缺乏、生产端缺乏创新的潜在风险,并提出创新发展的建议:加强生产端互联网的建设,提高创新质量;深化完善商业生态系统建设,提高商业系统整体的创新能力。  相似文献   
107.
For option pricing models and heavy-tailed distributions, this study proposes a continuous-time stochastic volatility model based on an arithmetic Brownian motion: a one-parameter extension of the normal stochastic alpha-beta-rho (SABR) model. Using two generalized Bougerol's identities in the literature, the study shows that our model has a closed-form Monte Carlo simulation scheme and that the transition probability for one special case follows Johnson's distribution—a popular heavy-tailed distribution originally proposed without stochastic process. It is argued that the distribution serves as an analytically superior alternative to the normal SABR model because the two distributions are empirically similar.  相似文献   
108.
109.
[目的]通过测算各地区农业科技资源的配置能力,分析其比较优势并找出不足以便弥补差距,促进各区域农业科技配置能力的提高,为各地区农业经济的发展提供支持。省级农业科学院作为各省市规模最大、综合实力最强的农业科研机构,是农业科技创新的重要主体之一,分析其科技资源配置能力具有重要的现实意义。[方法]基于2009—2016年相关数据,遴选了有代表性的评价指标体系,运用突变级数法计算农业科技资源配置能力,运用NRCA模型定量分析农业科技资源配置效益的比较优势。[结果]山东农业科学院科技资源配置能力位居全国第一,甘肃、江苏、青海农业科学院分别在农业科技人力、物力、财力资源方面具有明显的比较优势。[结论]省级农业科学院科技资源配置能力区域差异十分明显,但区域格局变化不大,且大致与各地区经济实力相吻合;农业科技资源配置能力较高的农业科学院大多在农业科技物力资源配置效益方面具有比较优势,在农业科技人力、财力资源配置效益方面不具备比较优势。  相似文献   
110.
This paper uses a spatial econometrics approach to study the industry risks in China’s stock market. We comprehensively consider the real linkage and information risk transmission channels and analyze the risk spillovers of specific determinants. Our empirical results show the following: 1) The real linkage channel and information channel are both effective transmission channels for driving spillover effects, and the information channel is of the utmost importance. 2) The spillover effects of specific determinants exist and are persistent. The superposition of spillover effects may lead to extreme risk. 3) The transmission channels and spillover effects are asymmetric in different regimes.  相似文献   
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