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61.
Electric vehicles (EVs) acknowledged as potential means of transportation tools in the near future are widely accepted as the development trend of automobile industry due to its environment protection and fuel energy saving properties. As a product containing new technologies and concepts with little market experience and consumer identification, studying its life cycle operation modes will help to figure out an optimal approach to conduct EVs manufacturing and service. The two common operation modes, lease and sale of EVs, have their own advantages and weaknesses under different scenarios and consumer psychological status. Research and comparisons on the function, cost and value of two operation modes in full life cycle will simulate the rapid development of EVs forming a mature and dynamic operation mechanism. This paper utilised approaches in value engineering, putting forward customer requirements and technical elements of EV lease and sale based on quality assessment and customer-perceived value, proposing the metric method of function and cost coefficient by mathematical modelling, and conducting value coefficient analysis and comparison based on customer’s risk aversion psychology. An illustrative example raised for studying operation mode of three different kinds of EVs based on the analysis of value coefficient, providing guideline for manufacturer and servicers of EVs. 相似文献
62.
Context: Prostate cancer (PCa) is the second most-frequently diagnosed cancer in men. Cabazitaxel was approved for the treatment of patients with hormone-refractory metastatic prostate cancer previously treated with a docetaxel-containing regimen.Objective: In this study, bombesin (BN), a ligand reported to specifically target GRP overexpressing prostate tumor, was applied for the construction of lipid-polymer hybrid nanoparticles (LPNs), and used for the targeted delivery of cabazitaxel (CAB) to prostate cancer.Methods: BN-polyethylene glycol-1,2-Distearoyl-sn-glycero-3-phosphoethanolamine (BN-PEG-DSPE) was synthesized. CAB loaded, BN-PEG-DSPE contained LPNs (BN-CAB-LPNs) were prepared. Their particle size, zeta potential and drug encapsulation efficiency (EE) were evaluated. In vitro cytotoxicity study of BN-CAB-LPNs was tested in LNCaP human prostatic cancer cell line (LNCaP cells). In vivo anti-tumor efficacy of the carriers was evaluated on mice bearing prostate cancer model.Results: The optimum BN-CAB-LPNs formulations had a particle size of 184.9?nm and a 26.5?mV positive surface charge. The growth of LNCaP cells in vitro was obviously inhibited. BN-CAB-LPNs also displayed better anti-tumor activity than the other formulations in vivo.Conclusion: The results demonstrated that BN-CAB-LPNs can sufficiently deliver CAB to the cancer cells and enhance the anti-tumor capacity. Thus, BN-CAB-LPNs can be proved to be a superior nanomedicine which can achieve better therapeutic efficacy of prostate tumor. 相似文献
63.
Angular Dependence of Exchange Bias and Magnetization Reversal Controlled by Electric‐Field‐Induced Competing Anisotropies 下载免费PDF全文
64.
Xiaoshuai Li Zhengwei Yuan Xiaowei Wei Hui Li Guifeng Zhao Jiaoning Miao Di Wu Bo Liu Songying Cao Dong An Wei Ma Henan Zhang Weilin Wang Qiushi Wang Hui Gu 《Journal of materials science. Materials in medicine》2016,27(4):77
Spina bifida aperta are complex congenital malformations resulting from failure of fusion in the spinal neural tube during embryogenesis. Despite surgical repair of the defect, most patients who survive with spina bifida aperta have a multiple system handicap due to neuron deficiency of the defective spinal cord. Tissue engineering has emerged as a novel treatment for replacement of lost tissue. This study evaluated the prenatal surgical approach of transplanting a chitosan–gelatin scaffold seeded with bone marrow mesenchymal stem cells (BMSCs) in the healing the defective spinal cord of rat fetuses with retinoic acid induced spina bifida aperta. Scaffold characterisation revealed the porous structure, organic and amorphous content. This biomaterial promoted the adhesion, spreading and in vitro viability of the BMSCs. After transplantation of the scaffold combined with BMSCs, the defective region of spinal cord in rat fetuses with spina bifida aperta at E20 decreased obviously under stereomicroscopy, and the skin defect almost closed in many fetuses. The transplanted BMSCs in chitosan–gelatin scaffold survived, grew and expressed markers of neural stem cells and neurons in the defective spinal cord. In addition, the biomaterial presented high biocompatibility and slow biodegradation in vivo. In conclusion, prenatal transplantation of the scaffold combined with BMSCs could treat spinal cord defect in fetuses with spina bifida aperta by the regeneration of neurons and repairmen of defective region. 相似文献
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Influence maximization of temporal social networks (IMT) is a problem that aims to find the most influential set of nodes in the temporal network so that their information can be the most widely spread. To solve the IMT problem, we propose an influence maximization algorithm based on an improved K-shell method, namely improved K-shell in temporal social networks (KT). The algorithm takes into account the global and local structures of temporal social networks. First, to obtain the kernel value Ks of each node, in the global scope, it layers the network according to the temporal characteristic of nodes by improving the K-shell method. Then, in the local scope, the calculation method of comprehensive degree is proposed to weigh the influence of nodes. Finally, the node with the highest comprehensive degree in each core layer is selected as the seed. However, the seed selection strategy of KT can easily lose some influential nodes. Thus, by optimizing the seed selection strategy, this paper proposes an efficient heuristic algorithm called improved K-shell in temporal social networks for influence maximization (KTIM). According to the hierarchical distribution of cores, the algorithm adds nodes near the central core to the candidate seed set. It then searches for seeds in the candidate seed set according to the comprehensive degree. Experiments show that KTIM is close to the best performing improved method for influence maximization of temporal graph (IMIT) algorithm in terms of effectiveness, but runs at least an order of magnitude faster than it. Therefore, considering the effectiveness and efficiency simultaneously in temporal social networks, the KTIM algorithm works better than other baseline algorithms. 相似文献
67.
为了真实仿真飞控襟翼系统部件的功能和接口,替代系统真件参与试验,探查飞控襟翼操纵系统的组成结构和工作原理,设计并实现了基于PXI的飞控襟翼仿真系统;根据真件相关资料,建立了完整的襟翼操纵系统闭环控制模型,建设了襟翼硬件仿真测试平台,编制了仿真测试软件;仿真系统硬件采用模块化结构设计,提高了稳定性和可靠性;系统软件基于QNX实时操作系统编制,保证了仿真测试过程中事件响应的实时性;成果在实际工作中成功应用于飞控系统联测,满足了仿真系统的功能需求和技术指标. 相似文献
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Jian-You Guo Miao Yu Jing Wang Bao-Mei Yao Peng Jiao 《Computer Physics Communications》2010,181(3):550-556
We develop the complex scaling method within the relativistic framework by expanding the Dirac spinors in the complete set of eigensolutions of a harmonic oscillator potential, and present the theoretical formalism of describing the discrete bound and resonant states on the same footing. Based on a well established and frequently used model, we demonstrate the utility and applicability of the extended method and examine the stability of the results with respect to the variations of the parameters of the model. Satisfactory agreements are found for all the calculated results in comparison with some other calculations in references. Especially, the present calculation in the nonrelativistic limit gives a consistent result with that in the nonrelativistic calculation. 相似文献