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91.
ABSTRACT

This paper analyses the role of user-supplier relationships in the innovation dynamics of the Oil and Gas (O&G) industry, from an analysis supported by R&D and patent application data. This paper points to some recent interesting phenomena in the O&G sector, such as: (i) the remarkable advancement of two Chinese oil companies; (ii) the significant growth in O&G companies’ technological engagement in exploration and production (E&P) from the 2000s; (iii) the non-negligible increase in the application of O&G companies’ patents for renewable energy. Moreover, by working with the oil and gas chain complete, we show that the performance of the companies oil and gas equipment and services industry (O&GES) is restricted to the upstream activities. Finally, we bring up some arguments that have as objective relativise the typology of R&D intensity adopted by OECD.  相似文献   
92.
基于引证关系,利用知识图谱、社会网络分析等方法,对1981—2019年《经济地理》创刊以来知识溢出的特征与变化规律进行分析。经济地理学研究的专业综合性、学科交叉性特点,在《经济地理》期刊知识溢出的特征与变化中得以充分诠释。期刊知识溢出的作用与变化,不仅体现在促进作者合作网络形成与机构合作关系的深化上,也体现在对城市化、区域经济发展、区域旅游发展等研究领域的推动作用与变化上。期刊知识溢出的特征与变化在其主题构成、作者贡献、机构力量与前沿引领等的探讨中进一步得以明确。具体地,城市化研究的知识溢出作用,从城市化和城镇化、土地利用、生态环境等方面,逐渐转向新型城镇化、城市网络、生态环境、协调发展等主题;区域经济发展研究的知识溢出作用,经历了从经济联系转向产业集群、再转向空间相互作用关系的主题变化;区域旅游发展研究的知识溢出作用,则从旅游资源、旅游业、生态旅游等方面,逐步转向乡村旅游、旅游经济与协调发展等主题。以国家战略与发展政策为主要导向,促进国内经济地理学的研究与发展,是《经济地理》期刊知识溢出的核心内容与集中反映。  相似文献   
93.
In this paper, we propose a goal-based investment model that is suitable for personalized wealth management. The model only requires a few intuitive inputs such as size of wealth, investment amount, and consumption goals from individual investors. In particular, a priority level can be assigned to each consumption goal and the model provides a holistic solution based on a sequential approach starting with the highest priority. This allows strict prioritization by maximizing the probability of achieving higher priority goals that are not affected by goals with lower priorities. Furthermore, the proposed model is formulated as a linear program that efficiently finds the optimal financial plan. With its simplicity, flexibility, and computational efficiency, the proposed goal-based investment model provides a new framework for automated investment management services.  相似文献   
94.
重叠滤波多音(O-FMT)是针对滤波多音(FMT)系统频谱利用率低的缺点而根据超奈奎斯特(FTN)概念引入子载波重叠得到的方案。鉴于O-FMT系统在频偏环境下的性能缺陷,理论分析了频偏对系统信号各部分的影响,比较了O-FMT与正交频分复用(OFDM)系统的抗频偏性能。针对频偏性能优化问题,提出了基于最佳线性无偏估计(BLUE)的改进盲估计算法,设计了基于频域滤波器系数的内嵌结构进行频偏补偿。仿真实验表明,O-FMT相比OFDM具有更好的抗频偏能力,改进的盲估计算法估计值精度更高,抗干扰、抗衰落能力更强,设计的频偏补偿结构可以使系统获得更好的性能。  相似文献   
95.
The extant literature on behavioral corporate finance has explored the effects of overconfidence on investment–cash flow sensitivity (ICS) to explain overinvestment, yet it has overlooked the asymmetric behavior of investments in relation to changes in cash flow levels. This study examines whether investments behave asymmetrically responding to changes in cash flows and, if so, how managerial overconfidence affects asymmetric ICS. Using a sample of KOSPI and KOSDAQ firms in Korea, we find the incidence of downwardly sticky ICS in unconstrained firms. We then find that overconfident managers encourage ICS to be stickier than their rational peers do in unconstrained firms. Finally, we find that managerial overconfidence intensified by self-attribution bias induces ICS to get even stickier, suggesting more explicit evidence of corporate investment distortions. The results of alternative tests using the asymmetric models of Homburg and Nasev (2008) are qualitatively consistent with prior results. Overall, our findings imply a higher incidence of excessive investment commitments driven by overconfident managers.  相似文献   
96.
针对不完备信息系统条件下的辐射源威胁等级判定问题,提出了一种基于改进容差关系粗糙集(ITR-RS)的不完备信息系统辐射源威胁等级判定方法。该方法将粗糙集中的不完备信息系统理论引入辐射源威胁等级判定中,并构建一套完备的决策规则提取模型。此外,利用辨识矩阵实现对属性的约简,在降低系统所需处理数据量的同时,提高了算法的实时性;在容差关系粗糙集的基础上,提出一种改进的容差关系,在属性主、客权重相结合的基础上引入阈值来划分加权阈值容差类,得到更为合理、准确的决策规则。仿真试验及分析表明,与经典RS算法相比,所提算法的威胁等级判定正确率提高了23%,可用于信息系统不完备条件下的辐射源威胁等级判定。  相似文献   
97.
Most leisure research does not consider collective action and social change, while most social movement research overlooks carnivality and spontaneity. A counter-example is the alternative bicycling movement critical mass (CM), a rebellious, liberatory leisure and cultural event. CM is goal-oriented and a libidinal expression of participant desire. This paper investigates CM’s production of happiness and freedom via three heterodox theories. Ecstatic rituals are repetitive, cathartic collective events that people engage in to express joy and flaunt convention. Political theories of play interpret individual’s physically-embodied, creative, and performative actions. Temporary autonomous zones are spatial locations of resistance to authority that evade state detection and suppression. CM – unlike standard bike races or conventional movement protest – transcends the limitations of physical exercise, lackadaisical leisure, and militant direct action. Instead it is a hybrid form of collective action, combining premeditated ritual, rebellious play, and mobile freedom-seeking.  相似文献   
98.
Research Summary: While prior studies have predominantly shown that CEO narcissism and hubris exhibit similar effects on various strategic decisions and outcomes, this study aims to explore the mechanisms underlying how narcissistic versus hubristic CEOs affect their firms differently. Specifically, we investigate how peer influence moderates the CEO narcissism/hubris—corporate social responsibility (CSR). With a sample of S&P 1500 firms for 2003–2010, we find that the positive relationship between CEO narcissism and CSR is strengthened (weakened) when board‐interlocked peer firms invest less (more) intensively in CSR than a CEO's own firm; the negative relationship between CEO hubris and CSR is strengthened when peer firms are engaged in less CSR than a CEO's own firm. Managerial Summary: Some CEOs are more narcissistic while others may be more hubristic, but these two groups of CEOs hold different attitudes toward the extent to which their firms should engage in corporate social responsibility (CSR). Our findings with a large sample of U.S. publically listed firms suggest that narcissistic CEOs care more about CSR, but hubristic CEOs care less. Interestingly, when narcissistic CEOs observe their peer firms engaging in more or less CSR than their own firms, they tend to respond in an opposite manner; in contrast, hubristic CEOs will only engage in even less CSR when their peers also do not emphasize CSR. Our findings point to a fundamental difference between CEO narcissism and hubris in terms of how they affect firms' CSR decisions based on their social comparison with peer firms.  相似文献   
99.
ABSTRACT

The food and beverage sector of the hospitality industry is known for being an emotionally labor-intensive environment. The events that transpire over the course of a shift lead to various emotions, which ultimately dictate the behaviors of the employees working in this industry. Of particular interest to this study was the interplay between environmental antecedents (power and distributive justice) and their influence on a negative emotion (anger) and a positive emotion (affective organizational commitment). Additionally, this study sought to understand how anger and affective organizational commitment influenced positive (organizational citizenship behavior) and negative (counterproductive work behavior) workplace behaviors using the lens of the affective events theory. The results of this study revealed that anger had the strongest effect on counterproductive work behavior and that all of the relationships were significant except from anger to affective organizational commitment and affective organizational commitment to counterproductive work behavior.  相似文献   
100.
Multinational enterprises (MNEs) make investment decisions according to the distance factors at a sub-national level. This paper made estimates using the gravity model with provincial foreign direct investment (FDI) data from 2000 to 2012 and employed three concepts of distance. Our empirical results indicate that geographic distance and cultural distance have significant negative effects on FDI flow, whereas economic distance has a significant positive effect. It suggests that FDI prefers to locate in regions that are geographically and culturally close but economically distant from the home country, which further implies that FDI in China is dominated by vertical FDI. Our findings suggest that Chinese provincial governments should place emphasis on attracting FDI from culturally close countries and provide institutional support to encourage and promote horizontal FDI.  相似文献   
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