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排序方式: 共有854条查询结果,搜索用时 15 毫秒
321.
Dan Zhang Xiaojing Su Hao Chang Hao Xu Xiaolei Wang Xiaobin He Junjie Li Fei Zhao Qide Yao Yanna Luo Xueli Ma Hong Yang Yongliang Li Zhenhua Wu Yajuan Su Tao Yang Yayi Wei Anyan Du Huilong Zhu Junfeng Li Huaxiang Yin Jun Luo Tianchun Ye Wenwu Wang 《清华大学学报》2022,(3):534-558
This article reviews advanced process and electron device technology of integrated circuits, including recent featuring progress and potential solutions for future development. In 5 years, for pushing the performance of fin field-effect transistors(FinFET) to its limitations, several processes and device boosters are provided. Then, the three-dimensional(3 D) integration schemes with alternative materials and device architectures will pave paths for future technology evolution. Finally, it could... 相似文献
322.
A tool for the manual annotation of cross-document entity and event coreferences that helps annotators to label mention coreference relations in text is essential for the annotation of coreference corpora. To the best of our knowledge, CROss-document Main Events and entities Recognition(CROMER) is the only open-source manual annotation tool available for cross-document entity and event coreferences. However, CROMER lacks multi-language support and extensibility. Moreover, to label cross-document... 相似文献
323.
Deep learning algorithms have been widely used in computer vision, natural language processing and other fields. However, due to the ever-increasing scale of the deep learning model, the requirements for storage and computing performance are getting higher and higher, and the processors based on the von Neumann architecture have gradually exposed significant shortcomings such as consumption and long latency. In order to alleviate this problem, large-scale processing systems are shifting from a t... 相似文献
324.
Effect of sintering on the relative density of Cr-coated diamond/Cu composites prepared by spark plasma sintering 下载免费PDF全文
Cr-coated diamond/Cu composites were prepared by spark plasma sintering. The effects of sintering pressure, sintering temperature, sintering duration, and Cu powder particle size on the relative density and thermal conductivity of the composites were investigated in this paper. The influence of these parameters on the properties and microstructures of the composites was also discussed. The results show that the relative density of Cr-coated diamond/Cu reaches ~100% when the composite is gradually compressed to 30 MPa during the heating process. The densification temperature increases from 880 to 915℃ when the diamond content is increased from 45vol% to 60vol%. The densification temperature does not increase further when the content reaches 65vol%. Cu powder particles in larger size are beneficial for increasing the relative density of the composite. 相似文献
325.
Xiao Zheng-yan Xu Xu-song . School of Mathematics Statistics Wuhan University Wuhan Hubei China . Technology Economics Management Institute Wuhan University Wuhan Hubei China 《武汉大学学报:自然科学英文版》2003,8(4):1057-1060
0 IntroductionWhenthepricesofriskyassetssatisfythegeometricBrow nianmotionandtheinvestor’sutilityfunctionisamem beroftheHARAfamily ,Mertoncompletelysolvedtheconsump tionportfolioproblem [1 2 ] .Buttheequitypremium puzzle[3] andtherisklessinterestratepuzzle[4] meanthatthesimpleHARAfamilyu tilityfunctioncannotdescribetheinvestor’scomplexbehavior,sotheutilityfunctionhastobeextendedtomoregeneralcase.Zoufirstintroducesthepreferenceforwealthbylettingthewealthasanargumentofutilityfunction[5] … 相似文献
326.
Composite briquettes containing high-phosphorus oolitic hematite and coal were produced with a twin-roller briquette machine using sodium carboxymethyl cellulose, molasses, starch, sodium silicate, and bentonite as binders. The effect of these binders on the strength of the composite briquettes, including cold strength and high-temperature strength, was investigated by drop testing and compression testing. It was found the addition of Ca(OH)2 and Na2CO3 not only improved the reduction of iron oxides and promoted dephosphorization during the reduction-separation process but also provided strength to the composite briquettes during the briquetting process; a compressive strength of 152.8 N per briquette was obtained when no binders were used. On this basis, the addition of molasses, sodium silicate, starch, and bentonite improved the cold strength of the composite briquettes, and a maximum compressive strength of 404.6 N per briquette was obtained by using starch. When subjected to a thermal treatment at 1200℃, all of the composite briquettes suffered from a sharp decrease in compressive strength during the initial reduction process. This decrease in strength was related to an increase in porosity of the composite briquettes. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses showed that the decrease in strength of the composite briquettes could be caused by four factors: decomposition of bonding materials, gasification of coal, transportation of byproduct gases in the composite briquettes, and thermal stress. 相似文献
327.
The design of DNA sequence plays an important role in improving the reliability of DNA computation. Proper constrained terms that DNA sequence should satisfy are selected, and then the evaluation formulas of each DNA individual corresponding to the selected constrained terms are proposed. The heuristic improved genetic algorithm (GA)/simulated annealing (SA) algorithm is presented to solve the multi-objective optimize problem, and the DNA sequence design system is developed. Furthermore, an example is illustrated to show the efficiency of our method given here. 相似文献
328.
南海表层水温年循环的谐波特征 总被引:1,自引:1,他引:1
通过对NCEP1°×1周平均SST资料(1982-1994)进行谐波分析,发现南海SST年循环中基波W1和第二谐波W2是决定性的谐波,诸谐波具有准驻波特征;气候平均意义下的季节内振荡不显著,此外,还讨论了南海全区SST在夏季风爆发之前迅速增温的原因。 相似文献
329.
We propose an efficient scheme to generate multi-photon entangled W state from two-qubit Einstein-Podolsky-Rosen pairs by measurements and follow-up local transformation. We discuss the efficiency of the scheme under realistic conditions, and its implementation using current technology. 相似文献
330.
Li Zhao Fen Xu Chenchen Zhang Zhenyue Wang Hanyu Ju Xu Gao Xiaoxu Zhang Lixian Sun Zongwen Liu 《自然科学进展(英文版)》2021,31(2):165-179
The global energy crisis and environmental pollution have caused great concern. Hydrogen is a renewable and environmentally friendly source of energy and has potential to be a major alternative energy carrier in the future.Due to its high capacity and relatively low cost of raw materials, alanate has been considered as one of the most promising candidates for hydrogen storage. Among them, LiAlH4 and NaAlH4, as two representative metal alanates, have attracted extensive atte... 相似文献