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91.
This paper introduces a new family of portmanteau tests for serial correlation. Using the wavelet transform, we decompose the variance of the underlying process into the variance of its low frequency and of its high frequency components and we design a variance ratio test of no serial correlation in the presence of dependence. Such decomposition can be carried out iteratively, each wavelet filter leading to a rich family of tests whose joint limiting null distribution is a multivariate normal. We illustrate the size and power properties of the proposed tests through Monte Carlo simulations.  相似文献   
92.
Due to the serious increase of environmental pollution in China, environmental regulations have become significantly stringent. Such regulations are playing an increasingly important role in the development of small enterprises (SEs) in China, especially in SEs' market entry. However, existing studies pay little attention to this issue. This paper investigates for the first time the effect of environmental regulations on SEs' market entry and the mechanism of environmental regulation effects in China. We consider two sets of panel data for the periods 2003–2010 and 2012–2015 in China. We also use the fixed effect model and the instrumental variable method to explore the role of environmental regulations in SEs' market entry. The results show that, overall, environmental regulations play a significantly positive and robust role in SEs' market entry. However, the mechanisms associated with the effect of environmental regulations on different innovative types of SEs differ. Environmental regulations promote the market entry of SEs with product innovation, but this impact is not significant for SEs with research and development (R&D) activities and R&D institutions. Our findings indicate that China's SEs prefer product innovation, which is a lower level innovative type, over R&D innovation, as a means to avoid the negative impact of stringent environmental regulations.  相似文献   
93.
At the beginning of the 21st century, the Netherlands and Flanders introduced a risk-based approach to flood risk management (FRM), labelled as multi-layer (water) safety. In contrast to a flood defence approach, risk-based management stresses the need to manage both the consequences and probability of a flood. The concept has developed differently in the two countries, as we conclude from a discursive-institutionalist research perspective. The Netherlands is characterised by a high institutionalization of the traditional flood defence discourse and a more closed policy arrangement, whereas in Flanders, the flood defence discourse is less institutionalized and the arrangement is more open. In both countries we see an opening of the arrangement preceding the establishment of multi-layer (water) safety, but at the same time, actors stress different aspects of the concept in order to increase its compatibility with the existing policy arrangement. In the Netherlands, the focus is on probability management, in Flanders on consequence management. In the Netherlands, multi-layer (water) safety as a concept could be established because it stabilises the system in the short-term by reinforcing the importance of flood defence, whereas in Flanders, policymakers were receptive to the concept because it supports a shift of responsibility towards actors outside traditional water management.  相似文献   
94.
The experience curve is a tool for forecasting future decreases in average cost as a function of cumulative output/volume. The extent of an experience effect has profound implications for both pricing strategy and the focus on market share as a managerial objective. At the same time, the underlying sources of the experience effect are not well understood. This article demonstrates that, as commonly measured, experience effects are aggregated with the effects of increasing returns to scale. This implies that standard experience curve estimates are misspecified because they suffer from an omitted variable bias. Strategic implications of the experience‐scale link are discussed.  相似文献   
95.
This study examines unique factors causing emerging market firms to pursue functional upgrading. Our analysis draws on the resource-based view and learning theory, and our study sample consisted of Chinese new technology ventures. We test the effect of governance mechanisms and internal resources on the functional upgrading of firms. The results indicate that trade shows and quality advantage facilitated the functional upgrading of firms. However, contrary to our expectations, electronic markets and technological advancement do not emerge as significant variables. The implications of the results are discussed in consideration of the existing literature, and future research opportunities are described.  相似文献   
96.
97.
It is well known that intra-industry trade and cross-border production networks have promoted economic growth and regional integration in East Asia. However, regional supply and production chains may have been formed differently across industries, reflecting different degrees and a different scope of regional economic linkages at an industry level. This paper makes a threefold contribution. First, to assess industry-level differences, this study adopts the generalized purchasing power parity (G-PPP) model using industry-specific producer prices. Second, the momentum threshold autoregressive (M-TAR) model is employed to allow for possible nonlinearity arising from the dynamic nature of regional economic growth and development. Third, the Granger causality test is also conducted to assess whether regional economies have autonomously integrated. The empirical results reveal that economic integration has progressed more autonomously in the electrical industry, as well as in the transportation equipment industry, as China and the ASEAN countries have become the final destination markets for finished products in these two industries.  相似文献   
98.
本文建立了同时测定欧盟高关注物质(SVHC)第23批新增的4种物质[1-乙烯基咪唑、-甲基咪唑、4-羟基苯甲酸丁酯、双(乙酰丙酮酸)二丁基锡的气相色谱质谱联用仪(GC-MS)]的检测方法。将样品用二氯甲烷超声后,采用选择离子监控模式(SIM)进行分析样品中的待测物。实验结果表明,4种物质在50 mg/L范围内线性关系良好,线性相关系数为0.995以上;样品加标回收率为94%110%,相对标准偏差(RSD)小于7%;方法检出限分别为2 mg/kg、10mg/kg、0.8 mg/kg、0.6 mg/kg,解决了欧盟新增加的4种SVHC测试问题。  相似文献   
99.
Drawing on the board capital literature, we use a panel data design to investigate the effect of boardroom nationality on the profitability and solvency of property-casualty insurers operating in the United Kingdom (UK). We find that boardroom nationality influences corporate outcomes depending on the financial aspects being measured. For example, North American directors are linked with profitable outcomes, while European directors tend to be associated with better solvency. This reflects differences between the shareholder value corporate culture in North America and stakeholder approaches more common in Europe. Our results could help insurers, regulators, and others (e.g., investors) to better understand the potential performance implications of the appointment of directors of different nationality.  相似文献   
100.
UxDMA算法是一种高效的集中式算法,是用于时分多址、频分多址和码分多址信道分配的统一算法。在UxDMA的基础上,利用多波束天线的多波束形成能力,针对低时延定向ad hoc网络提出了一种集中式调度算法——CLSM(Centralized Low-delay Scheduling Algorithm Based on Multi-beam Antennas)。CLSM通过不同时延等级限制的报文来比较着色后发送链路的优先级,优先选择高优先级链路传输。通过仿真验证了CLSM的性能:与UxDMA相比,该算法在多时延限制的发送端调度中表现出了更好的吞吐量和时延性能。  相似文献   
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