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71.
In this paper, we study the excursions of Bessel and Cox–Ingersoll–Ross (CIR) processes with dimensions . We obtain densities for the last passage times and meanders of the processes. Using these results, we prove a variation of the Azéma martingale for the Bessel and CIR processes based on excursion theory. Furthermore, we study their Parisian excursions, and generalize previous results on the Parisian stopping time of Brownian motion to that of the Bessel and CIR processes. We obtain explicit formulas and asymptotic results for the densities of the Parisian stopping times, and develop exact simulation algorithms to sample the Parisian stopping times of Bessel and CIR processes. We introduce a new type of bond, the zero‐coupon Parisian bond. The buyer of such a bond is betting against zero interest rates, while the seller is effectively hedging against a period where interest rates fluctuate around 0. Using our results, we propose two methods for pricing these bonds and provide numerical examples.  相似文献   
72.
本文充分考虑劳动异质性,利用产业人力资本结构,重新核算三次产业结构偏离度,发现第一产业和第三产业结构偏离程度均被高估,第二产业结构偏离被低估,进而指出“民工荒”、大学生就业难等现象产生的原因是第一产业可转出人力资本减少,第二产业需求旺盛,而第三产业由于发展不足陷入低水平均衡状态。最后通过系统的影响因素分析发现,解决我国结构偏离和就业问题的重点在于优化需求结构、合理规划产业发展路径以及全面推进城镇化和市场化进程,关键更在于释放农村消费市场巨大潜力和全面加快第三产业发展。  相似文献   
73.
This research focuses on understanding the air taxi operations to determine the number of air taxis required to fulfill the demand for urban air mobility in New York City (NYC). We leverage the Define, Measure, Analyze, Design, and Verify (DMADV) framework and integrate it with the systems simulation approach. Upon investigation, we find that all the parameters linearly impact the vehicle utilization, while other measures are robust, specifically with respect to the seating capacity. It is also recommended to operate initially with 70 air taxis in NYC to achieve a trade-off between customer wait time and vehicle utilization. The proposed approach can act as a recommender system for air taxi companies.  相似文献   
74.
针对鹤煤九矿井下硐室出现浆皮开裂、底臌等类似现象,采用相似模拟的方法,以鹤煤九矿31采区避难硐室临近硐室群实际地质资料为基础,研究分析了给定应力环境下不同支护方式时硐室围岩的变形破坏情况、失稳过程。作者认为,随着顶部压力的逐渐改变,顶板裂隙逐渐增加,裂隙深度和宽度逐步增加,巷道出现离层、底鼓,进而呈现大面积破坏。该结果对区段巷道布置与加固方案优化有一定的参考价值。  相似文献   
75.
We compare the prioritized projects of the Master Plan on ASEAN Connectivity (MPAC) and the Comprehensive Asia Development Plan (CADP) by utilizing the Institute of Developing Economies/Economic Research Institute for ASEAN and East Asia Geographical Simulation Model. The prioritized projects of the MPAC mainly focus on specific hard or soft infrastructure projects connecting one remote area of an ASEAN member state to another and thus fail to capture the full potential of the infrastructure because of neglected important links within a state. On the other hand, the CADP emphasizes the importance of economic corridors or linkages between a large cluster and another cluster. Our simulation analysis shows that CADP projects will result in an addition to gross domestic product (GDP) of $US 1544bn over the period from 2021 to 2030 (in 2010 dollars) or an impact on ASEAN countries that is 12 times larger than MPAC projects. The results strongly suggest that the CADP projects should be adopted and implemented to fully realize the potential economic growth of the ASEAN countries. Moreover, the CADP will contribute more to narrowing the development gaps among the ASEAN countries than MPAC prioritized projects.  相似文献   
76.
There are many barriers and challenges associated with climate change communication focused on promoting community-based action for sustainable futures. Of particular interest is the challenge to embed community perspectives in a communication process of climate change solutions. In this paper we argue that 3D interactive simulations using design inquiry as a development process, can be an effective way of communicating climate change solutions and multiple community responses. People are more likely to engage with the challenges associated with complexity of climate change at the local level when their perspectives are integrated into viable and multiple pathways for action. Future scenarios of change processes situated in local experiences in compelling and interactive ways can be disseminated holistically by making links between scientific, social, political, economic and cultural elements. Design inquiry, as a research approach, integrates contextual knowledge into communication processes to aid imagining, re-thinking and reembodying viable pathways that explore the kinds of futures we collectively envision. This paper examines the contributions that design inquiry makes to climate change communication using an interactive simulation environment for designing futures. We discuss these ideas using the example of the Future Delta project, a virtual 3D environment that enables the exploration and simulation of multiple community-based climate change solutions in the Corporation of Delta, British Columbia.  相似文献   
77.
The issue of future airport capacity in London is currently the subject of much political debate in the UK. Although realistic estimates of the effects of capacity enhancement may be desirable, such estimates are difficult. Through the use of Monte Carlo simulation, this paper quantifies and compares the relative capacity enhancements that may be afforded by the construction of a new hub airport in the Thames Estuary, additional runways at Heathrow, Gatwick and Stansted and changes to operating practices at Heathrow. The simulations show that a new hub airport would be the most effective way to increase capacity, although the reported financial and environmental costs of such a development indicate a comparatively poor rate of return. Proposed new runways at Heathrow, Gatwick and Stansted and the removal of runway alternation at Heathrow provide more modest increases in capacity.  相似文献   
78.
I examine the determinants of both perceived inflation and unemployment in one single survey and include Big Five traits in the analysis. This is the first survey on this topic in Germany. My sample consists of 1771 students from different fields and levels. Using PhD students’ estimates as a reference, I create categories for underestimation and overestimation of both variables. Multinomial logit regressions show that females overestimate both variables. Education and news consumption reduce misestimation. A higher level of Neuroticism is related with a higher probability to overestimate unemployment. Overstating (understating) one indicator is associated with overstating (understating) the other.  相似文献   
79.
The standard textbook analysis shows that drivers as a group lose from congestion charges. However, it omits taste heterogeneity, shorter travel times far out in the larger network arising from less blocking back of upstream links and the possibility for drivers to reschedule. Taking account of these factors, using a dynamic scheduling model with heterogeneous users we find that all three add significantly to the benefit of the Stockholm congestion charges and that drivers as a group benefit from these charges even without recycling of revenues. This paper also provides an update on the consumer benefits of the Stockholm charges.  相似文献   
80.
由于目前关于建筑行业资质管理对建筑产业的有效性存在正反两方面不同看法,双方虽有定性理论分析和国外资质管理根据,但是无法说明资质管理对我国建筑产业整体收益具体影响,因而从个体企业行为角度出发,根据多智能体理论,使用Netlogo建模平台,建立中国建筑业的交易行为互动流程,模拟运行建筑产业执行或不执行资质管理的情况,观察并分析论证了资质管理有利于提高中国建筑产业收益能力。此外,在模拟过程中发现资质管理对产业结构也存在影响。  相似文献   
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