随着建筑工程规模和结构复杂度的不断增加,连续钢构节段拼装精度控制与缝宽调整技术在现代工程中具有重要的实际意义。将广佛西环五工区工程作为具体案例,深入探讨了连续钢结构拼装过程中的精度控制技术和缝宽调整方法。通过分析节段预...随着建筑工程规模和结构复杂度的不断增加,连续钢构节段拼装精度控制与缝宽调整技术在现代工程中具有重要的实际意义。将广佛西环五工区工程作为具体案例,深入探讨了连续钢结构拼装过程中的精度控制技术和缝宽调整方法。通过分析节段预制精度、运输与吊装过程中的精度控制,以及拼装过程中的实时监测与调整,提出了基于建筑信息模型(Building Information Modeling,BIM)技术的精度控制辅助应用。在缝宽调整方面,详细阐述了缝宽调整的基本原则与目标,介绍了不同施工阶段应用的缝宽调整技术,为复杂钢结构工程的施工提供参考。展开更多
We have fabricated a series of square-lattice hole photonic crystal (2PhC) arrays simultaneously at the un-current injection region on a special sample of GaN based light emitting diode (LED) by using focus ion beam m...We have fabricated a series of square-lattice hole photonic crystal (2PhC) arrays simultaneously at the un-current injection region on a special sample of GaN based light emitting diode (LED) by using focus ion beam milling (FIBM). The lattice constants of the 2PhC arrays vary from 230 to 1500 nm,while the 2PhC arrays have a constant area of about 9 μm×18 μm and a fixed depth of 150±10 nm which approaches but does not penetrate the active layer. Microscopic electroluminescence images and spectral measurements consistently confirm that the top emitting intensities from different 2PhCs are all enhanced compared with the unpatterned region. It is demonstrated that the output coupling of propagating guided modes is realized by the diffracted transmission of the 2PhCs. The enhancement factors of the guided modes compared with the unpatterned region are plotted as function of the lattice constant. It is found that the highest enhancements for the extraction of guided modes were obtained for the lattice constant of 230 and 460 nm of 2PhCs. The results are discussed by the two-dimensional rigorous coupled wave analysis (RCWA).展开更多
The lattice-parameter effects on the diffracted transmission of GaN square-lattice photonic crystals （2PhC） at the wavelength of 460 nm were studied by using a rigorous coupled wave analysis （RCWA）. The impacts of...The lattice-parameter effects on the diffracted transmission of GaN square-lattice photonic crystals （2PhC） at the wavelength of 460 nm were studied by using a rigorous coupled wave analysis （RCWA）. The impacts of lattice parameters on the diffracted transmission are calculated in the ranges for lattice pitch from 100 nm to 2000 nm, fill factor from 0.1 to 0.9 and grat- ing height from 100 nm to 1000 rim, respectively. Our simulation results confirm that the lattice pitch is the dominant factor of the diffraction. It determines how many orders of diffraction occur by the 2PhCs. The larger the lattice pitch, the higher the diffraction orders come into play. Moreover, besides the first-order Bragg diffraction, higher diffraction orders from large pitches of PhCs are also beneficial to the light extraction improvement. The higher enhancement factors of the integrated transmission were obtained from a wide range of pitches with micro-scale GaN 2PhCs. Three different diffraction mechanisms through wave vector analysis were used to discuss the simulation results.展开更多
文摘随着建筑工程规模和结构复杂度的不断增加,连续钢构节段拼装精度控制与缝宽调整技术在现代工程中具有重要的实际意义。将广佛西环五工区工程作为具体案例,深入探讨了连续钢结构拼装过程中的精度控制技术和缝宽调整方法。通过分析节段预制精度、运输与吊装过程中的精度控制,以及拼装过程中的实时监测与调整,提出了基于建筑信息模型(Building Information Modeling,BIM)技术的精度控制辅助应用。在缝宽调整方面,详细阐述了缝宽调整的基本原则与目标,介绍了不同施工阶段应用的缝宽调整技术,为复杂钢结构工程的施工提供参考。
基金supported by the National Basic Research Program of China ("973" Project) (Grant Nos.2007CB307004,2006CB921607)the National Natural Science Foundation of China (Grant Nos.60776041,60976009,U0834001)
文摘We have fabricated a series of square-lattice hole photonic crystal (2PhC) arrays simultaneously at the un-current injection region on a special sample of GaN based light emitting diode (LED) by using focus ion beam milling (FIBM). The lattice constants of the 2PhC arrays vary from 230 to 1500 nm,while the 2PhC arrays have a constant area of about 9 μm×18 μm and a fixed depth of 150±10 nm which approaches but does not penetrate the active layer. Microscopic electroluminescence images and spectral measurements consistently confirm that the top emitting intensities from different 2PhCs are all enhanced compared with the unpatterned region. It is demonstrated that the output coupling of propagating guided modes is realized by the diffracted transmission of the 2PhCs. The enhancement factors of the guided modes compared with the unpatterned region are plotted as function of the lattice constant. It is found that the highest enhancements for the extraction of guided modes were obtained for the lattice constant of 230 and 460 nm of 2PhCs. The results are discussed by the two-dimensional rigorous coupled wave analysis (RCWA).
基金supported by the National Key Basic R&D Plan Projects (‘973’ Project) of China (Grant Nos.2007CB307004,2006CB921607)National Natural Science Foundation of China (Grant Nos.60776041,60976009,U0834001)
文摘The lattice-parameter effects on the diffracted transmission of GaN square-lattice photonic crystals （2PhC） at the wavelength of 460 nm were studied by using a rigorous coupled wave analysis （RCWA）. The impacts of lattice parameters on the diffracted transmission are calculated in the ranges for lattice pitch from 100 nm to 2000 nm, fill factor from 0.1 to 0.9 and grat- ing height from 100 nm to 1000 rim, respectively. Our simulation results confirm that the lattice pitch is the dominant factor of the diffraction. It determines how many orders of diffraction occur by the 2PhCs. The larger the lattice pitch, the higher the diffraction orders come into play. Moreover, besides the first-order Bragg diffraction, higher diffraction orders from large pitches of PhCs are also beneficial to the light extraction improvement. The higher enhancement factors of the integrated transmission were obtained from a wide range of pitches with micro-scale GaN 2PhCs. Three different diffraction mechanisms through wave vector analysis were used to discuss the simulation results.
