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991.
Xiaoyong Yuan Gongbing Bi Baofeng Zhang Yugang Yu 《International Transactions in Operational Research》2020,27(6):3079-3103
This paper considers a one‐period supply chain consisting of a risk‐averse retailer and a risk‐neutral supplier. As a Stackelberg leader, the supplier produces short life‐cycle products to the retailer and determines the option price. The newsvendor‐like retailer orders call option from the supplier with an emergency order opportunity. The analytical model shows that when the emergency purchase price is low, the risk‐averse retailer's optimal order quantity is less than that of a risk‐neutral retailer and independent of the retail price. It is surprising that when it is moderate or high, the risk‐averse retailer may order less than, equal to, or more than a risk‐neutral one. Computational studies are given to investigate the key parameters on optimal decisions and profits. It shows a risk‐averse retailer may get higher profit than a risk‐neutral one. The retailer benefits from a low emergency purchase price, while it harms the supplier. 相似文献
992.
Hongping Li Gongbing Bi Xiaoyong Yuan Dong Wang 《International Transactions in Operational Research》2020,27(5):2340-2369
We examine the role of trade credit insurance in a capital‐constrained supply chain with one (or two) loss‐neutral retailer(s) and one loss‐averse manufacturer. We model the interplay between these supply chain participants as a Stackelberg game and analyze their operating and financing decisions. In one capital‐constrained retailer case, we find that either the manufacturer's high loss aversion level or the retailer's low initial capital motivates the manufacturer to adopt insurance. Insurance drives more credit financing with more attractive financing terms (a lower wholesale price), which promotes the manufacturer to collect better product sales and performance. Although the retailer enjoys improved profit from insurance, its default risk increases. In contrast, in one capital‐constrained retailer and one well‐funded retailer scenario, numerically, when the manufacturer's loss aversion level is high or the weak retailer's initial capital is low, insurance is also adopted but is not always preferred by the capital‐constrained retailer due to competition. In addition, as the demand substitution rate increases, the manufacturer is more likely to prefer insurance due to better performance. 相似文献
993.
Chuntao Wei Xiaoyong Li Yuebing Wang Fangyu Liu 《International journal of remote sensing》2019,40(20):7750-7766
This paper proposes an unsupervised change detection method for very-high-resolution (VHR) remote sensing images based on multi-resolution Markov random field (MRF) model in wavelet domain. Firstly, the wavelet transform is performed on the difference image achieved by the change vector analysis (CVA) method, and the wavelet coefficients at each scale are obtained. Then, MRF model is constructed based on the wavelet coefficients. The wavelet high-frequency coefficients establish a feature field model that describes the feature attributes of each pixel location at each scale. The initial change map (changed and unchanged) at the coarse scale are generated through applying the k-means method to the wavelet low-frequency coefficients, and a label field model describing the region of the variation results is established. The label and feature field, at the same scale, got the optimized change map under the Bayesian criterion. Finally, the results of the low-resolution scale change map are directly projected as the adjacent higher-scale initial change map. The more accurate change map is obtained successively from the coarse scale to the original resolution scale, and the detection result of the original resolution is obtained at last. Experiments on Quick Bird, SPOT-5, and IKONOS optical images have demonstrated the effectiveness of the proposed method. The experimental results show that the method has better regional consistency and strong robustness. 相似文献
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996.
Xue Liu Chao Liu Zizheng Zheng Siyuan Chen Xin Pang Xinchu Xiang Jixian Tang En Ren Yuanzhi Chen Min You Xiaoyong Wang Xiaoyuan Chen Wenxin Luo Gang Liu Ningshao Xia 《Advanced materials (Deerfield Beach, Fla.)》2019,31(17)
The ability to selectively kill cancerous cell populations while leaving healthy cells unaffected is a key goal in oncology. The use of nanovesicles (NVs) as chemotherapeutic delivery vehicles has been recently proven successful, yet monotherapy with monomodalities remains a significant limitation for solid tumor treatment. Here, as a proof of principle, a novel cell‐membrane‐derived NVs that can display full‐length monoclonal antibodies (mAbs) is engineered. The high affinity and specificity of mAb for tumor‐specific antigens allow these vesicular antibodies (VAs) to selectively deliver a cytotoxic agent to tumor cells and exert potent inhibition effects. These VAs can also regulate the tumor immune microenvironment. They can mediate antibody‐dependent cellular cytotoxicity to eradicate tumor cells via recruitment and activation of natural killer cells in the tumor. Upon further encapsulation with chemotherapeutic agents, the VAs show unequaled cooperative effects in chemotherapy and immunotherapy in tumor‐bearing mice. As far as it is known, this is the first report of a VA‐based multifunctional combination therapy platform. This might lead to additional applications of vesicular antibodies in cancer theranostics. 相似文献
997.
探讨了在当前WLAN覆盖范围不断扩大,用户要求带宽不断增加的背景下,本地传输网如何承载WLAN业务,对PON及PrN承载的选择,提出了在新的形式下,WLAN业务承载的传输网络建设思路和操作方法。 相似文献
998.
Multi-level Topological Relations Between Spatial Regions Based Upon Topological Invariants 总被引:1,自引:0,他引:1
Topological relations have played important roles in spatial query, analysis and reasoning. In a two-dimensional space (IR2), most existing topological models can distinguish the eight basic topological relations between two spatial regions. Due
to the arbitrariness and complexity of topological relations between spatial regions, it is difficult for these models to
describe the order property of transformations among the topological relations, which is important for detailed analysis of
spatial relations. In order to overcome the insufficiency in existing models, a multi-level modeling approach is employed
to describe all the necessary details of region–region relations based upon topological invariants. In this approach, a set
of hierarchically topological invariants is defined based upon the boundary–boundary intersection set (BBIS) of two involved
regions. These topological invariants are classified into three levels based upon spatial set concept proposed, which include
content, dimension and separation number at the set level, the element type at the element level, and the sequence at the
integrated level. Corresponding to these hierarchical invariants, multi-level formal models of topological relations between
spatial regions are built. A practical example is provided to illustrate the use of the approach presented in this paper.
相似文献
Zhilin LiEmail: |
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