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101.
102.
《Optimization》2012,61(7):779-804
We introduce a unifying model for contests with perfect discrimination and show that it can be used to model many well-known economic situations, such as auctions, Bertrand competition, politically contestable rents and transfers, tax competition and litigation problems. Furthermore, we hope that the generality of our model can be used to study models of contests in settings in which they have not been applied yet. Our main result is a classification of the set of Nash equilibria of first-price winner-takes-all contests with complete information. Finally, we discuss the implications of our results in each one of the specific models. 相似文献
103.
The beam transport design of a novel proton dielectric wall accelerator is introduced in this paper. The protons will be accelerated from 40 keV to nearly 1 MeV under an accelerating gradient that is as high as 20 MV/m. A consideration of the beam line as well as the transport simulation is presented. The influences of the injection timing jitter and the accelerating pulse timing jitter are also discussed. 相似文献
104.
Large eddy simulations of a circular orifice jet with and without a cross-sectional exit plate 下载免费PDF全文
The effect of a cross-sectional exit plane on the downstream mixing characteristics of a circular turbulent jet is in- vestigated using large eddy simulation (LES). The turbulent jet is issued from an orifice-type nozzle at an exit Reynolds number of 5 ×104. Both instantaneous and statistical velocity fields of the jet are provided. Results show that the rates of the mean velocity decay and jet spread are both higher in the case with the exit plate than without it. The existence of the plate is found to increase the downstream entrainment rate by about 10% on average over the axial range of 8-30de (exit diameter). Also, the presence of the plate enables the formation of vortex rings to occur further downstream by 0.5-1 .Ode. A physical insight into the near-field jet is provided to explain the importance of the boundary conditions in the evolution of a turbulent jet. In addition, a method of using the decay of the centreline velocity and the half-width of the jet to calculate the entrainment rate is proposed. 相似文献
105.
In this paper,we consider the Brownian motion risk model with interest.The Laplace transform of the first exit time from the upper barrier before hitting the lower barrier is obtained.Using the obtained result and exploiting the limitation idea,we derive the Laplace transform of total duration of negative surplus. 相似文献
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107.
通过对高维Kramers系统与之对应稳态Fokker-Planck方程的渐近分析,仔细探讨了该系统在平衡点吸引域的边界上离出点的分布问题.运用变量替换、匹配原理、局部坐标变换、边界层展开等方法,对外解、远离鞍点处的边界层及鞍点处的边界层进行分析,得出离出点分布的渐近表达式. 相似文献
108.
本文选取了2008年1月1日至2012年12月31日间首次进行股权激励草案公告的245家A股上市公司作为研究对象,运用事件研究法对上市公司公告股权激励草案前后的超额收益情况进行检验.研究发现:即使不考虑股权激励本身带来的短期市场效应,草案公告日也更可能出现在股价低点,说明管理层会对草案公告的时机进行选择.进一步的研究则表明管理层是利用了自身对于公司季度盈余报告的信息优势来进行草案公告日的选择. 相似文献
109.
Jun Seok Kim Hee-Sung Ahn Soo Min Cho Ji Eun Lee YoungSoo Kim Cheolju Lee 《Analytica chimica acta》2014
Amyloid-β (Aβ) in human plasma was detected and quantified by an antibody-free method, selected reaction monitoring mass spectrometry (SRM-MS) in the current study. Due to its low abundance, SRM-based quantification in 10 μL plasma was a challenge. Prior to SRM analysis, human plasma proteins as a whole were digested by trypsin and high pH reversed-phase liquid chromatography (RPLC) was used to fractionate the tryptic digests and to collect peptides, Aβ1–5, Aβ6–16, Aβ17–28 and Aβ29–40(42) of either Aβ1–40 or Aβ1–42. Among those peptides, Aβ17–28 was selected as a surrogate to measure the total Aβ level. Human plasma samples obtained from triplicate sample preparations were analyzed, obtaining 4.20 ng mL−1 with a CV of 25.3%. Triplicate measurements for each sample preparation showed CV of <5%. Limit of quantification was obtained as 132 pM, which corresponded to 570 pg mL−1 of Aβ1–40. Until now, most quantitative measurements of Aβ in plasma or cerebrospinal fluid have required antibody-based immunoassays. Since quantification of Aβ by immunoassays is highly dependent on the extent of epitope exposure due to aggregation or plasma protein binding, it is difficult to accurately measure the actual concentration of Aβ in plasma. Our diagnostic method based on SRM using a surrogate peptide of Aβ is promising in that actual amounts of total Aβ can be measured regardless of the conformational status of the biomarker. 相似文献
110.