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关键词： Carbon dioxide removal   Climate change   Integrated assessment   Mitigation   Negative emissions   Steady-state game  

摘要： In this paper, we propose a simple oligopoly game model to represent the interactions between coalitions of countries in deploying carbon dioxide removal (CDR) strategies in a steady-state net-zero emission climate regime that could take place by the end of the twenty-first century. The emission quotas and CDR activities obtained in the solution of this steady-state model could then be used as a target for end-of-period conditions in a dynamic integrated assessment analysis studying the transition to 2100. More precisely, we analyze a steady-state situation where m coalitions exist and behave as m players in a game of supplying emission rights on an international emission trading system. The quotas supplied by a coalition must correspond to the amount of CO2 captured through CDR activities in the corresponding world region. We use an extension of the computable general equilibrium model GEMINI-E3 to calibrate the payoff functions and compute an equilibrium solution in the noncooperative game.

关键词： Biodiversity conservation   Agroecology   Functional ecology   Ecological strategy   Species spillover   Plant traits   Field margin   Disturbance  

摘要： The widespread loss of weed diversity and associated ecosystem functions is raising important concerns. Field edges could play a major role in the maintenance of weed functional diversity in arable landscapes as these habitats still harbour high weed diversity, owing to either a reduced farming management intensity and/or to a spillover of species from adjacent perennial field margins. Here, we investigated the taxonomic and functional characteristics of weed species recorded in surveys of field edges and their associated field cores over six consecutive years in 60 arable fields farmed with five crop management strategies. We found that field edges were richer, with species more functionally diverse and composition more stable over years than field core surveys. The distribution of individual functional traits differed between field edges and field cores, with higher values for seed mass and nitrophily (Ellenberg.N), and a wider distribution of specific leaf area values in field edges. The bimodal distribution of plant height and germination period observed in field edges became unimodal in field cores. Field edges harboured species with ecological strategies associated with field cores (ruderal species) plus a conservative strategy which could be explained by a spillover from the adjacent perennial field margins. Crop management strategies impacted field edge flora, though to a lesser extent than the field core flora whereas the functional differences between the field edge and the field core flora were less marked when crop management intensity was lower. These results indicate that field edges harbour a unique assemblage of species and highly contribute to the maintenance of weed diversity in arable landscapes. Future studies should thus focus on the importance of these specific functional traits to the agroecosystem functioning. (C) 2021 Published by Elsevier GmbH on behalf of Gesellschaft fur okologie.

关键词： Physical model testing   Managed ice-field   Dynamic positioning   Ice-field parameters   Ice-vessel interactions  

摘要： This paper presents details of an extensive physical model testing program for evaluating the performance of a dynamic positioning (DP) controlled vessel in different realistic managed ice environments. It describes the model vessel, the preparation of the ice-field, the procedure of the model tests, the methodologies of data analysis, and highlights of the measurements. A simplified generic drillship model at 1:40 scale was tested in multiple managed ice configurations. A total of 372 test runs were carried out in 17 ice sheets to evaluate the thruster forces and motion responses of the vessel in various ice conditions. The physical and mechanical characteristics of the ice-field were modelled by controlling ice concentration, thickness, floe size, flexural strength, and the ice drift speed and direction. The ice concentration ranged from a light condition (7/10th) to a heavy condition (9/10th+) with multiple ice floe sizes ranging between 25 m to 100 m. Also, multiple ice thicknesses ranging between 0.60 m to 2.0 m and multiple ice drift speeds (0.2 knots, 0.5 knots, and 1.2 knots) with various moderate to extreme ice drift angles were investigated. The thruster forces on the model vessel along the surge and sway directions and the yawing moment were measured. Besides, the vessel model's 6-DOF motions and accelerations were recorded. Multiple cameras were used to capture the global and local ice-structure interactions placed in different above-water locations. All reported values presented in the paper are in full-scale unless otherwise specified. The time series of thruster forces and yawing moments are presented along with the vessel's positioning capabilities in various managed ice conditions. Results and discussions on the effects of various managed ice-field parameters on the time-averaged thruster forces and moment are offered. Generally, the analysis reveals that each of the ice parameters under investigation had a moderate to strong effect on global thrust

关键词： 管理学  

ISBN: (纸本)9787030711298

摘要： 本书设计九个章节、四个知识模块介绍管理信息系统的基本概念、相关技术、建设理论和案例实践。其中，第一章和第二章为理论模块，阐述管理信息系统的基本概念。第三章为技术支持模块，简要介绍管理信息系统涉及的各类技术。第四章到第八章为系统建设模块，从系统的生命周期视角介绍系统建设的各个环节。第九章为案例分析模块，结合一个项目场景综合运用本书的理论与实践知识，介绍项目的建设过程。

关键词： Calvarial lesions   Imaging   Histiocytosis   Meningiomas   Metastases  

摘要： Calvarial lesions are rare and can present as a variety of different diseases. The lesions can be palpable on the skin and cause local pain and paraesthesia and, depending on the location, neurological deficits can also occur. This research aims to present an overview of typical imaging features as well as neurosurgical management. We examined the charts of patients who underwent surgery on a calvarial lesion in our department between 2004 and 2017 (n=133). Retrospectively, the pre-, intra-, and postoperative data were analyzed with morphological and histological findings and compared with each other. Pain, swelling, cosmetically disturbing, and neurological deficits were the main complaints. Seventy-seven lesions were limited to the bone, while another 56 lesions showed an infiltrating growth in the adjacent tissue. Depending on the clinical signs and suspected diagnosis, a biopsy, a partial removal, or a complete resection was performed. Histiocytosis (n=20), meningiomas (n=20), metastases (n=19), and osteomas (n=16) were the most common lesions. Fibrous dysplasia (n=6) and intraosseous hemangioma (n=9) were less common;other lesions were present only in isolated cases. Imaging features may suggest the lesion to be benign or malignant, but the diagnosis can be only confirmed by histological examination. The surgical strategy depends on the complaints, location of the lesion, and suspected diagnosis. Adjuvant treatment should be initiated according to the histological findings.

关键词： Cournot oligopoly   Reinforcement learning   Imitation  

摘要： This paper analyzes the learning behavior of firms in a repeated Cournot oligopoly game. Literature shows the degree of information and cognitive capacity of learning firms is a key factor that determines long run outcome of an oligopoly market. In particular, when firms possess the knowledge of market demand and are capable of computing the optimal production quantity given the output of other firms, the resulting market outcome is the Nash equilibrium. On the other hand, imitation that assumes low behavioral sophistication of firms generally favors higher output and converges to the Walrasian equilibrium. In this paper, a reinforcement learning algorithm with low cognitive requirement is adopted to model firms' learning behavior. Reinforcement learning firms observe past production choices and fine tune them to improve profits. Analytical result shows that the Nash equilibrium is the only fixed point of the reinforcement learning process. Convergence to the Nash equilibrium is observed in computational simulations. When firms are allowed to imitate the most profitable competitor, all states between the Nash equilibrium and the Walrasian equilibrium can be reached. Furthermore, the long run outcome shifts towards the Nash equilibrium as the length of firms' memory increases.

关键词： 药品管理   管理信息系统   预警系统   系统建模   研究  

ISBN: (纸本)9787576102444

摘要： 药品安全关系人民群众的身体健康和生命安全，关系社会和谐稳定。党和国家领导人历来重视药品工作，多次作出重要批示指示，要求用“四个最严”对药品生产、流通、使用等各环节加强监管，坚决杜绝各类药品质量安全事件的发生，包括监管部门、药品企业、医疗机构等在内的各方在各个环节共同维护药品安全。药品安全预警系统对药品全生命周期过程中存在的异常现象进行警示，防范各类药品质量安全事件发生，能够起到预防不良事件发生的作用。

关键词： Internationalization   Culture   Knowledge   Higher education  

摘要： This paper aims to overcome the weaknesses of the relationship between knowledge management with a competitive advantage by adding management behavior as a mediating variable in the relationship of knowledge management with the internationalization strategy, which is an effort to increase competitive advantage in higher education. Respondents in this study were 198 people of structural officials managing colleges in 55 universities in Indonesia. The result shows that, from 7 hypotheses which are proposed, only 4 hypotheses are significant that are supported by empirical data. Market characteristics, cultural understanding, and knowledge management significantly affect management behavior and do not significantly affect the internationalization strategy. Furthermore, management behavior significantly affects internationalization strategy and can mediate relationships between market characteristics, cultural understanding, and knowledge management with internationalization strategy.

关键词： advertising   differential game   general demand and cost functions   oligopoly  

摘要： We present an analysis of advertising activities in a dynamic oligopoly with differentiated goods using a differential game approach under general demand and cost functions. The main conclusion is that the memoryless closed-loop solution and the feedback solution are equivalent when there is no spillover effect of advertising activities. We also show that the comparison of the open-loop solution and the memoryless closed-loop solution depends on whether the firms' outputs are strategic substitutes or strategic complements.

关键词： Oligopoly equilibrium   Pollution permit markets   Pollution   Supply subsidy  

摘要： We introduce a competitive pollution permit market in a two-sector oligopoly equilibrium model. In this model, one commodity is inelastically supplied by one competitive trader and another one is produced by a finite set of oligopolists, using the first commodity as an input. The production of the second commodity is a polluting activity. We study both the competitive and oligopoly equilibria. We provide some conditions under which a supply subsidy given to the oligopolists that is financed by a tax on the competitive agent is Pareto-improving.