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1.
Companies commonly issue sustainability or corporate social responsibility (CSR) reports. This study seeks to understand worldviews of corporate sustainability, or the corporate message conveyed regarding what sustainability or CSR is and how to enact it. Content analysis of corporate sustainability reports is used to position each company report within stages of corporate sustainability. Results reveal that there are multiple coexisting worldviews of corporate sustainability, but the most dominant worldview is focused on the business case for sustainability, a position anchored in the weak sustainability paradigm. We contend that the business case and weak sustainability advanced in corporate sustainability reports and by the Global Reporting Initiative are poor representations of sustainability. Ecological embeddedness, or a locally responsive strategy that is sensitive to local ecosystems, may hold the key to improved ecological sensemaking, which in turn could lead to more mature levels of corporate sustainability worldviews that support strong sustainability and are rooted in environmental science. This must be supported by government regulation. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment  相似文献   
2.
Since the Global Financial Crisis, credit risk and its management have become one of the most appealing topics in finance literature. In this study, we investigate the interaction of credit risk and liquidity risk through the TED and the OIS spreads and various credit default swap indexes from the CDX and the iTraxx family (CDXIG, CDXHY, ITEEU, and ITEXO). The empirical analysis is conducted through the Kapetanios unit root test, the EGARCH model, the Bootstrap Toda-Yamamoto modified Wald test and the asymmetric causality analysis. The results of symmetric and asymmetric causality methods reveal that liquidity risk appears to play an important role in credit risk, and in most cases, the TED and the OIS spreads dominate the CDS indexes. It can, thus, be concluded that the TED and the OIS spreads are superior to the CDS indexes as an early warning indicator in the credit market.  相似文献   
3.
针对高灵敏度接收机对频率合成器的高技术指标要求,构建了一种融合了直接模拟、直接数字以及间接数字的频率合成技术方案,根据该方案,成功实现了频率合成器的工程研制。通过测试,频率合成器相位噪声达-112 dBc/Hz@5 kHz,杂散抑制优于-75 dBc,频率分辨率小于1 kHz,10 MHz跳频时间约为13 μs,满足了高灵敏度接收机对频率合成器的高技术指标要求,为高纯度频率合成器的实现提供了一条新途径。  相似文献   
4.
采用响应面法优化毛竹水溶性多糖的提取工艺,分析其成分,并进行结构表征。研究结果表明,优化的毛竹多糖(BSP)提取条件为:料液比1∶27(g/mL)、提取温度78 ℃、提取时间4 h,该条件下BSP提取率为(5.18±0.07)%,提取物中多糖含量为(72.14±0.02)%,糖醛酸含量为(9.76±0.03)%;BSP具有酸性多糖典型的官能团特征吸收峰,其单糖组成及摩尔比为n甘露糖∶n葡萄糖∶n阿拉伯糖∶n木糖∶n鼠李糖∶n半乳糖=62.52∶23.05∶10.35∶2.78∶0.79∶0.51;BSP由两个主峰组成,相对分子质量分别为91.11、4.55 kDa。BSP是一种混合酸性多糖。  相似文献   
5.
Advances in the study of both markets and platforms contribute to economics. Platforms are typically digital markets, although platforms can designate markets generally. So, the economics of markets and the economics of platforms are one and the same. Platforms show the critical role of intermediaries in endogenous price adjustment and market clearing. The platform model remedies problems with general equilibrium analysis by combining and extending the basic Walrasian and Marshalian market models. The analysis of platforms provides explanations for the bid–ask spread, including market power, search costs, matching costs, adverse selection, and moral hazard. The study of platforms demonstrates the importance of participation and coordination in the formation of markets. The discussion emphasizes that platforms have significant implications for the theory of the firm. The analysis further considers how platforms affect innovation and entrepreneurship.  相似文献   
6.
This paper deals with precision farming tools (PFTs), a way of farming which relies on specialized equipment, software and information technologies services, whose importance is underlined in recent documents of the European Union. Precision farming is an integrated and sustainable farm management system making use of modern technologies to increase farm’s profitability, by reducing environmental impact. In this paper we explore the complex mechanisms that affect PFT’s adoption by Italian farmers. More precisely, we try to analyse the context-related factors affecting adoption of PFTs in the Italian farms.Little research has been carried out in Italy on this topic, therefore our paper tries to fill a gap in literature. In order to investigate the process of technology adoption related to precision agriculture, a questionnaire was submitted to a sample of Italian farms. The questionnaire has been structured in order to apply the AKAP (Awareness, Knowledge, Adoption, Product) sequence. Our analysis underlines that context-related factors are fundamental dimensions to be explored in order to specify uptake of PFTs. Therefore, the paper has relevant policy implications, within the context of a new participatory approach to agricultural innovation characterized by bottom-up processes boosted by farmers, which has informed the recent policies of agricultural innovation at the EU level.  相似文献   
7.
On 23 June, 2016, the UK held a referendum to decide whether to stay in the European Union or leave. The uncertainty surrounding the outcome of this referendum had major consequences for public policy, investment decisions, and currency markets. We discuss some of the subtleties involved in smoothing and disentangling poll data in light of the problem of tracking the dynamics of the intention to Brexit, and propose a multivariate singular spectrum analysis method that produces trendlines on the unit simplex. The trendline yield via multivariate singular spectrum analysis is shown to resemble that of local polynomial smoothing, and singular spectrum analysis presents the nice feature of disentangling the dynamics directly into components that can be interpreted as changes in public opinion or sampling error. The merits and disadvantages of some different approaches for obtaining smooth trendlines on the unit simplex are contrasted, in terms of both local polynomial smoothing and multivariate singular spectrum analysis.  相似文献   
8.
We examine whether professional forecasters incorporate high-frequency information about credit conditions when revising their economic forecasts. Using a mixed data sampling regression approach, we find that daily credit spreads have significant predictive ability for monthly forecast revisions of output growth, at both the aggregate and individual forecast levels. The relationships are shown to be notably strong during ‘bad’ economic conditions, which suggests that forecasters anticipate more pronounced effects of credit tightening during economic downturns, indicating an amplification effect of financial developments on macroeconomic aggregates. The forecasts do not incorporate all financial information received in equal measures, implying the presence of information rigidities in the incorporation of credit spread information.  相似文献   
9.
针对认知无线传感器网络中频谱接入算法的频谱利用率不高、重要经验利用率不足、收敛速度慢等问题,提出了一种采用优先经验回放双深度Q-Learning的动态频谱接入算法。该算法的次用户对经验库进行抽样时,采用基于优先级抽样的方式,以打破样本相关性并充分利用重要的经验样本,并采用一种非排序批量删除方式删除经验库的无用经验样本,以降低能量开销。仿真结果表明,该算法与采用双深度Q-Learning的频谱接入算法相比提高了收敛速度;与传统随机频谱接入算法相比,其阻塞概率降低了6%~10%,吞吐量提高了18%~20%,提高了系统的性能。  相似文献   
10.
为了降低研发成本,提高频谱系统的灵活性和缩短研制周期,提出了一种基于软件无线电的嵌入式频谱监测系统。首先研究了系统硬件平台组成和特点,在此基础上设计了一种灵活的软件定义系统架构;然后考虑到硬件平台自身性能的限制,重点研究了频率偏移校正、频谱扫描策略等关键技术,分别提出了基于GSM信号和温度传感器的频偏校正方法和基于相关性的扫频策略;最后通过具体实验,对系统性能进行验证与评估,结果表明所提出的频偏校正方法能够将绝对平均频偏控制在1.749×10-6以内,所设计的基于相关性的扫频策略对时变信号的频谱监测效果最好。  相似文献   
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