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993.
There are often the underlying cross relatedness amongst multiple tasks, which is discarded directly by traditional single-task learning methods. Since multi-task learning can exploit these relatedness to further improve the performance, it has attracted extensive attention in many domains including multimedia. It has been shown through a meticulous empirical study that the generalization performance of Least-Squares Support Vector Machine (LS-SVM) is comparable to that of SVM. In order to generalize LS-SVM from single-task to multi-task learning, inspired by the regularized multi-task learning (RMTL), this study proposes a novel multi-task learning approach, multi-task LS-SVM (MTLS-SVM). Similar to LS-SVM, one only solves a convex linear system in the training phrase, too. What’s more, we unify the classification and regression problems in an efficient training algorithm, which effectively employs the Krylow methods. Finally, experimental results on school and dermatology validate the effectiveness of the proposed approach. 相似文献
994.
HANG YU HAI MING JINGJING GONG HAITAO LI HUI HUANG KEMING PAN YANG LIU ZHENHUI KANG JIE WEI DONGTIAN WANG 《Bulletin of Materials Science》2013,36(3):367-372
Au/ZnO nanocomposites have been prepared by a simple chemical method. For the first time, the nanocomposites were directly used as photocatalysts for hydroxylation of aromatic hydrocarbons under UV and visible light irradiation. The results show that the as-prepared photocatalysts display high photocatalytic activity for UV and visible catalytic hydroxylation of benzene. Without the assistance of any solvent or additive, high selectivity and high conversion efficiency were still obtained. Different photocatalytic mechanisms were proposed depending on whether excitation happens on ZnO semiconductor or on the surface plasmon band of Au. The former is Au nanoparticles act as electron buffer due to irradiation by UV light and ZnO nanoparticles as reactive sites for hydroxylation of benzene, the latter is that Au nanoparticles act as light harvesters and inject electrons into ZnO conduction band and as photocatalytic sites under visible light irradiation. 相似文献
995.
Tao Yang Zuoquan Jiang Xiaodong Huang Huaixin Wei Jianyu Yuan Wei Yue Youyong Li Wanli Ma 《Organic Electronics》2013,14(9):2184-2191
Two new dibenzosuberane-substituted fullerene derivatives, dibenzosuberane-C60 mono-adduct (DBSCMA) and bis-adduct (DBSCBA) were synthesized using a classical cyclopropanation reaction via a tosylhydrazone route for application as acceptor materials in polymer solar cells (PSCs). DBSCBA shows good solubility in common organic solvents and both derivatives were characterized by 1HNMR, 13C NMR, MALD-TOF, elemental analysis and UV–vis absorption measurements. The shift of fullerene energy levels induced by the dibenzosuberane substitution was investigated by using theoretical simulations and ultraviolet photoelectron spectroscopy. Bulk-heterojunction PSCs based on poly (3-hexylthiophene) (P3HT) and dibenzosuberane-C60 derivatives were fabricated and optimized by adjusting the donor/acceptor ratio and using thermal annealing and solvent additive. The morphologies of the active layers processed under different conditions were also examined by atomic force microscopy. When tested under an illumination of AM 1.5 G at 100 mW/cm2, the highest power conversion efficiency of the devices using DBSCBA is 3.70% which is superior to that of conventional P3HT:PCBM devices. 相似文献
996.
简要的介绍了市政排水施工的作用、影响市政排水施工质量的因素以及市政排水施工中的常见问题,并提出了提高市政排水工程施工质量的有效措施,以期指导实践,保证市政排水工程的安全运行。 相似文献
997.
对发电机定子直流电阻历年的试验数据进行了比较和分析,简要总结出在进行发电机定子直流电阻试验时,减少直流电阻测量误差的方法和避免误判的试验注意事项. 相似文献
998.
本文阐述了工作面采长与采空区防灭火的关系,并以石港公司为例,通过计算明确了工作面采长的取值范围,并结合经济效益进行综合分析,最终确定石港公司工作面设计采长应为120m。充分论证了合理设计工作面采长可以有效防治自燃。 相似文献
999.
Recombinant buckwheat trypsin inhibitor (rBTI) was studied to evaluate if it could enter cancer cells and to determine the mechanism. Fluorescein isothiocyanate-labelled buckwheat trypsin inhibitor (FITC-BTI) entered Hep G2 cells in a concentration-dependent manner. FITC-BTI colocalised with labelled transferrin (Tf) in the punctate structure, implying that rBTI enters Hep G2 cells by clathrin-dependent endocytosis. Incubation of Hep G2 cells with different chemical inhibitors abolished diffuse, but not punctate fluorescence, thus indicating that membrane potential plays a critical role in this process. Impairment of clathrin-mediated endocytosis by RNAi with clathrin heavy chain greatly reduced or completely abolished both diffuse and punctate fluorescence, further supporting a theory of a single route of endocytosis. Consistent with our working hypothesis, Hep G2 cells which were arrested in the M phase did not show any vesicular or diffuse FITC-BTI. We conclude from these results that both endocytosis and membrane potential are required for rBTI entry into Hep G2 cells. 相似文献
1000.
为实现对高校大量教学资料的高效管理,利用Visual C++开发软件,并结合数据库技术开发了高校资料管理系统,所建立的数据库保证了对资料规范、高效的管理,所开发出的系统用户界面简单易用,大大提高了工作效率,进一步地提升了高校教学资料的使用价值。 相似文献