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排序方式: 共有530条查询结果,搜索用时 15 毫秒
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Jiahong Zhang Yong Zha Xiaohang Yue Zhongsheng Hua 《The Journal of the Operational Research Society》2016,67(2):312-324
In this paper we study the relationship between a firm (hotel) and a service platform (Ctrip.com). We start with a newsvendor hotel facing two kinds of customers. D-customers order the room directly from the hotel front desk; C-customers order the room through Ctrip.com. Ctrip.com charges the hotel while introducing its members to the hotel. The hotel decides how many rooms are allotted to Ctrip.com to achieve optimal profit. We consider the situation where one party’s demand cannot be observed by another, and study the commonly used wholesale price contract. Interestingly, the contract can always coordinate the system. We then investigate the influence of bargaining power on the profit division under situations where Ctrip.com and hotel, respectively, dominate the system, and find that increasing (or decreasing) a party’s bargaining power without considering the other does not necessarily benefit (or damage) the first party. Further, we discuss how the parties choose dominance and appropriate bargaining power to make a trade-off for better cooperation. An interesting phenomenon is that bargaining power for each party can be identical when any party dominates the system. We also propose a threshold at which the wholesale price contracts can always be the Pareto optimal for the channel. 相似文献
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Fast filtering algorithm based on vibration systems and neural information exchange and its application to micro motion robot 下载免费PDF全文
This paper develops a fast filtering algorithm based on vibration systems theory and neural information exchange approach. The characters, including the derivation process and parameter analysis, are discussed and the feasibility and the effectiveness are testified by the filtering performance compared with various filtering methods, such as the fast wavelet transform algorithm, the particle filtering method and our previously developed single degree of freedom vibration system filtering algorithm, according to simulation and practical approaches. Meanwhile, the comparisons indicate that a significant advantage of the proposed fast filtering algorithm is its extremely fast filtering speed with good filtering performance. Further, the developed fast filtering algorithm is applied to the navigation and positioning system of the micro motion robot, which is a high real-time requirement for the signals preprocessing. Then, the preprocessing data is used to estimate the heading angle error and the attitude angle error of the micro motion robot. The estimation experiments illustrate the high practicality of the proposed fast filtering algorithm. 相似文献
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荧光光谱法研究共存碳纳米管对牛血清白蛋白与加替沙星相互作用的影响 总被引:2,自引:0,他引:2
在模拟生理条件下,用荧光光谱法研究了碳纳米管对牛血清白蛋白和加替沙星荧光光谱特性的影响以及有无碳纳米管共存时加替沙星对牛血清白蛋白荧光光谱特性的影响.实验结果表明,加替沙星和碳纳米管都可以使牛血清白蛋白的荧光强度发生静态猝灭.在碳纳米管的存在下,加替沙星与牛血清白蛋白的结合作用有所减弱.Stern-Volmer荧光猝灭... 相似文献
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摘 要:金属钛原子在金刚石表面的结合强度直接影响金刚石真空介电窗口的使用性能和寿命. 本文通过基于密度泛函理论的第一性原理方法研究了Ti原子与不同氮掺杂位置的金刚石(001)界面的结合能、电荷分布和稳态几何结构. 结果表明:Ti原子与N原子取代掺杂在第二层C原子处金刚石表面的结合能比未掺杂和掺杂在第三层的结合能都高,达到-7.293 eV,使得金刚石表面形成的界面结构更加稳定,结合强度更好;通过电荷分布分析,N原子掺杂在第二层金刚石表面的Ti原子上的电荷转移最明显,对金刚石表面碳原子吸附最强,也具有更好的结合强度. 与未掺杂金刚石表面形成的Ti-C键键长相比,N掺杂在第二层和第三层C原子处金刚石表面形成的Ti-C键键长比前者分别长0.051 Å和0.042 Å,略有增加. 相似文献
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Suppose G is a simple connected n‐vertex graph. Let σ3(G) denote the minimum degree sum of three independent vertices in G (which is ∞ if G has no set of three independent vertices). A 2‐trail is a trail that uses every vertex at most twice. Spanning 2‐trails generalize hamilton paths and cycles. We prove three main results. First, if σ3G)≥ n ‐ 1, then G has a spanning 2‐trail, unless G ? K1,3. Second, if σ3(G) ≥ n, then G has either a hamilton path or a closed spanning 2‐trail. Third, if G is 2‐edge‐connected and σ3(G) ≥ n, then G has a closed spanning 2‐trail, unless G ? K2,3 or K (the 6‐vertex graph obtained from K2,3 by subdividing one edge). All three results are sharp. These results are related to the study of connected and 2‐edge‐connected factors, spanning k‐walks, even factors, and supereulerian graphs. In particular, a closed spanning 2‐trail may be regarded as a connected (and 2‐edge‐connected) even [2,4]‐factor. © 2004 Wiley Periodicals, Inc. J Graph Theory 45: 298–319, 2004 相似文献
520.
Yingying Zha Renjie Chai Qin Song Lin Chen Xinxing Wang Guosheng Cheng Mingliang Tang Ming Wang 《Journal of nanoparticle research》2016,18(5):122
Current studies have demonstrated the advantage of graphene-based materials, which suggests their potential usage for biomedical applications. However, the in vivo toxicity and performance of three-dimensional (3D) graphene foams (GFs) remain largely unclear. In the present study, we identified the short-term and long-term tissue responses to GFs or graphene oxide foams (GOFs) in a rat model of subcutaneous implantation. Results from blood biochemistry, hematological analysis, histological examination, and behavioral test all indicated nearly no noticeable in vivo toxicity in either GF- or GOF-implanted rats during the first 2 weeks post-implantation. In addition, hematoxylin and eosin (H and E) stained images showed GFs or GOFs remained in the subcutaneous implantation site for at least 7 months without significant degradation after implantation. Our study demonstrates the non-biodegradable feature of GFs and GOFs as implanted scaffolds, while they exhibit good biocompatibility in vivo. It adds new evidence for the in vivo toxicological study of GFs and GOFs, which may provide reference for their biomedical applications. 相似文献