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31.
This study assesses the level of sophistication of livestock products in Africa by evaluating technology intensity and economic complexity of each product. Using trade data from 1995 to 2012, livestock commodity exports are classified based on technology intensity. Employing a method of reflection in computing the economic complexity of export products, we find that one fifth of African livestock commodity exports are manufactured with low technology while the rest is composed of raw materials. The results also show that the ten most complex livestock commodities represent about a third of African livestock total exports while the world level is almost double this figure. Yet African countries spend a huge share of their wealth on importing complex products. The results imply that by exporting non-complex products Africa loses nearly a third of the total value of its livestock exports. To boost the value of livestock products, African countries should exploit their untapped potential while securing the domestic market to achieve import substitution. This can be done by integrating with global value chains or developing niche markets at the regional or international markets and improving productive capabilities.  相似文献   
32.
As local governments and corporations promote ‘climate friendliness’, and a low-carbon lifestyle becomes increasingly desirable, more middle- and upper-income urban residents are choosing to live near public transit, on bike- and pedestrian-friendly streets, and in higher-density mixed-use areas. This rejection of classical forms of suburbanization has, in part, increased property values in neighborhoods offering these amenities, displacing lower-income, often non-white, residents. Increased prevalence of creative and technology workers appears to accelerate this trend. We argue that a significant and understudied socio-environmental contradiction also occurs where the actual environmental outcomes of neighborhood transformation may not be what we expect. New research on greenhouse gas emissions shows that more affluent residents have much larger carbon footprints because of their consumption, even when reductions in transportation or building energy emissions are included. We describe an area in Seattle, Washington, the location of Amazon's headquarters, experiencing this contradiction and show a distinct convergence of city investments in low-carbon infrastructure, significant rises in housing prices and decreases in lower-income and non-white residents. We conclude with a discussion of a range of issues that require more attention by scholars interested in housing justice and/or urban sustainability.  相似文献   
33.
This study set out to evaluate the financing efficiency of low‐carbon companies. Applying a three‐stage data envelopment analysis with the data from 85 listed companies in China's low‐carbon industries over the period 2011 to 2017, this study has found that the overall financing efficiency of low‐carbon companies was relatively high, and the pure technical efficiency was quite steady over the period. The overall financing efficiency of these low‐carbon companies on average tended to change with the scale efficiency. This study has also shown that the scale efficiency was the main constraint influencing the financing efficiency of low‐carbon companies in China over the period. Our results are robust and have significant implications for policy makers and corporate managers.  相似文献   
34.
在传统的Polar码译码的基础上,引入辅助译码比特,构造了一个辅助的Polar码字以提高译码性能。辅助比特由信道选择辅助窗口内的信息位决定。接收端如译码失败,将进行二次译码尝试。译码方案分两阶段进行:基于相同结构的扩展生成矩阵,将辅助译码比特译出;结合译出的辅助比特,对原码字进行译码,提高译码成功率。仿真结果显示,使用所提方法进行译码,其译码性能明显优于普通串行抵消译码方法;与两种传统的自动重传请求方案相比,能分别获得1 dB和1.9 dB的性能增益。  相似文献   
35.
In this paper, we propose a Weighted Stochastic Mesh (WSM) algorithm for approximating the value of discrete‐ and continuous‐time optimal stopping problems. In this context, we consider tractability of such problems via a useful notion of semitractability and the introduction of a tractability index for a particular numerical solution algorithm. It is shown that in the discrete‐time case the WSM algorithm leads to semitractability of the corresponding optimal stopping problem in the sense that its complexity is bounded in order by with being the dimension of the underlying Markov chain. Furthermore, we study the WSM approach in the context of continuous‐time optimal stopping problems and derive the corresponding complexity bounds. Although we cannot prove semitractability in this case, our bounds turn out to be the tightest ones among the complexity bounds known in the literature. We illustrate our theoretical findings by a numerical example.  相似文献   
36.
Most empirical studies examining the impact of foreign direct investment (FDI) on economic development use aggregate monetary-based measures such as GDP or TFP growth as indicators for development. We deviate from this approach and use instead the recently developed economic complexity index; this measure summarises the complexity of the productive structure of an economy, and its values can be interpreted as the number of capabilities present in a country. These capabilities are units of productive knowledge necessary for the production of goods, and goods differ in the number of necessary capabilities. Furthermore, we use sectoral FDI data to take differences between sectors of an economy into account, since the number of necessary capabilities also varies between the sectors. In our empirical analysis, covering 63 developing and developed countries over the period 2005–14, we find that FDI in the tertiary sector has a statistically significant and robust positive effect on the number of capabilities, whereas FDI in the primary and secondary sectors generally does not increase the capability set of an economy.  相似文献   
37.
生产链上下游企业选择合适的合作机制对低碳产品定价及碳减排有重要影响。通过构建博弈模型分析三种不同合作机制下的低碳产品定价及碳减排问题:第一种合作机制即制造商与零售商进行合作,当两条生产链都选择这种合作机制时,能带来较高的碳减排率和较低的零售价格,这对制造商、零售商、消费者和环境都是有利的。第二种合作机制即两条生产链的制造商之间、零售商之间分别合作,这会带来较低的碳减排率和较高的零售价格,对两个制造商有利,而对零售商和消费者不利。分析前两种合作机制的利与弊提出第三种合作机制,即零售商和制造商共享利润下的有利于碳减排的策略。最后,结合案例讨论和数值分析的研究结果表明:当制造商和零售商收入共享比在一定范围内时,第三种合作机制可以给制造商和零售商带来更高的利润。由此为企业选择最佳的合作机制及合理的碳减排策略提供了理论指导。  相似文献   
38.
This paper aims to understand what goes on in the black box of successful, joined-up ICT-enabled service transformation, where complex interactions and integration must occur among the horizontal processes internal to a joined-up service delivery network, the vertical top-down processes of the organizations involved, and the change processes caused by using ICTs. A new conceptual framework is developed and applied to an illustrative case study of successful, joined-up service transformation in New Zealand.  相似文献   
39.
Resilience – a firm's ability to adapt, endure, quickly bounce back, and then thrive despite a catastrophic event – addresses diverse managerial constructs including performance (Carmeli & Markman, 2011). Our exploratory study expands this line of research by making two contributions: first, we develop and test a new revelatory measure for resilience – VOLARE – combining financial performance measures with volatility data. Then, applying this new measure to the financial industry, from 2002 to 2011, we identify highly resilient international financial services firms (IFSFs; e.g., banks) and compare them with less resilient IFSFs. Second, we assess three factors – bank size, home-market solidity, and product and market complexity – that the literature has traditionally shown to be highly predictive of banks’ performance. Consistent with our expectations, the results corroborate that VOLARE is complementary to, but distinct from, traditional financial measures of firm performance. We explain these deviations from traditional studies and suggest further research topics.  相似文献   
40.
ABSTRACT

Low-carbon mobility (LCM) features strongly in debates about the sustainability of cities and their resilience in the face of demographic, economic, and climate change. Transport is a major source of carbon emissions and there are indications that these continue to increase, despite the considerable recent advances in vehicle, engine, and fuel technologies. Reducing carbon emissions from transport may become more difficult, not easier. A particular issue relates to the New World cities, typified by those of North America and Australasia, which largely developed from the latter half of the nineteenth century onward and whose transportation systems were largely based around private vehicle ownership and usage. These cities are typically composed of low-density, dispersed suburbs, which are highly car dependent and resource and carbon emission intensive. This article develops a research agenda directed at determining and testing policy and planning measures relevant to the quest for low carbon mobility in New World cities. It suggests a rich agenda for essential research on LCM. Much of this agenda falls within the realm of the integration of transport and land use, with attention to urban design details to enhance the perceptions of and opportunities to use low carbon transport alternatives. Research topics identified for LCM research include (1) urban design and land use–transport integration (LUTI), (2) low carbon mobility policies directed at achieving widespread behavior change, (3) opportunities for new technology and its application, including requirements for systems and infrastructure, and (4) analysis and tools for informed decision making, including modeling, measurement, visualization, and especially assessment.  相似文献   
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