This paper presents an innovative eccentric jacket substructure for offshore wind turbines to better withstand intense environmental forces and to replace conventional X-braced jackets in seismically active areas. The...This paper presents an innovative eccentric jacket substructure for offshore wind turbines to better withstand intense environmental forces and to replace conventional X-braced jackets in seismically active areas. The proposed eccentric jacket comprises of completely overlapped joint at every joint connection. The joint consists of a chord and two braces in a single plane. The two braces are fully overlapped with a short segment of the diagonal brace welded directly onto the chord. The characteristic feature of this joint configuration is that the short segment member can be designed to absorb and dissipate energy under cyclic load excitation. The experimental and numerical study revealed that the completely overlapped joint performed better in terms of strength resistance, stiffness, ductility, and energy absorption capacity than the conventional gap joints commonly found in typical X-braced jacket framings. The eccentric jacket could also be designed to becoming less stiff, with an inelastic yielding and local buckling of short segment member, so as to better resist the cyclic load generated from intense environmental forces and earthquake. From the design economics, the eccentric jacket provided a more straightforward fabrication with reduced number of welded joints and shorter thicker wall cans than the conventional X-braced jacket. It can therefore be concluded based on the results presented in the study that by designing the short segment member in accordance with strength and ductility requirement,the eccentric jacket substructure supporting the wind turbine could be made to remain stable under gravity loads and to sustain a significantly large amount of motion in the event of rare and intense earthquake or environmental forces, without collapsing.展开更多
目的:研究完全腹腔镜胃癌根治术联合overlap吻合术对消化道重建、并发症及患者生活质量的影响。方法:选取2019年6月至2021年12月于蚌埠医学院第一附属医院接受诊治的110例胃癌患者为研究对象。根据不同手术方式分为对照组(传统腹腔镜胃...目的:研究完全腹腔镜胃癌根治术联合overlap吻合术对消化道重建、并发症及患者生活质量的影响。方法:选取2019年6月至2021年12月于蚌埠医学院第一附属医院接受诊治的110例胃癌患者为研究对象。根据不同手术方式分为对照组(传统腹腔镜胃癌根治术,n=60)与观察组(完全腹腔镜胃癌根治术联合overlap吻合术,n=50),比较2组手术疗效及并发症,并采用胃肠道生活质量表(Gastrointestinal Quality of Life,GIQLI)评估生活质量。结果:观察组手术全程用时、消化道重建用时、总失血量均少于对照组(均P<0.05);2组肿瘤大小、淋巴结清扫数比较差异均无统计学意义(均P>0.05)。观察组术后排气时间、流食进食时间、下地时间均少于对照组(均P<0.05);2组住院时间差异无统计学意义(P>0.05)。观察组术后并发症总发生率低于对照组(P<0.05)。随访6个月,2组GIQLI各维度得分及总分均高于出院当天(均P<0.05),观察组GIQLI各维度得分及总分均高于对照组(均P<0.05)。结论:完全腹腔镜胃癌根治术联合overlap吻合术能有效重建消化道,减少并发症,改善生活质量。展开更多
近年来,基于张量补全的频谱制图得到了广泛研究.目前用于频谱制图的张量补全算法大多隐含地假设张量具有平衡特性,而对于非平衡张量,难以利用其低秩性估计完整的张量信息,导致补全算法性能受损.本文提出基于重叠Ket增强(Overlapping Ket...近年来,基于张量补全的频谱制图得到了广泛研究.目前用于频谱制图的张量补全算法大多隐含地假设张量具有平衡特性,而对于非平衡张量,难以利用其低秩性估计完整的张量信息,导致补全算法性能受损.本文提出基于重叠Ket增强(Overlapping Ket Augmentation,OKA)和张量列车(Tensor Train,TT)的非平衡频谱制图算法,以解决非平衡张量在应用传统张量补全算法时性能下降的问题.首先使用OKA将低阶高维张量表示为高阶低维张量,在无信息损耗的情况下解决非平衡张量无法利用其低秩性进行张量补全的问题;然后使用TT矩阵化得到较平衡的矩阵,在维度较平衡条件下提高补全算法的精确度;最后利用高阶低维张量的低秩性,使用并行矩阵分解或基于F范数的无奇异值分解(Singular Value Decomposition Free,SVDFree)算法完成张量补全.仿真结果表明,针对非平衡张量,所提方案与现有的张量补全算法相比,可以获得更精确的无线电地图,同时所提SVDFree算法具有更低的计算复杂度.展开更多
文摘This paper presents an innovative eccentric jacket substructure for offshore wind turbines to better withstand intense environmental forces and to replace conventional X-braced jackets in seismically active areas. The proposed eccentric jacket comprises of completely overlapped joint at every joint connection. The joint consists of a chord and two braces in a single plane. The two braces are fully overlapped with a short segment of the diagonal brace welded directly onto the chord. The characteristic feature of this joint configuration is that the short segment member can be designed to absorb and dissipate energy under cyclic load excitation. The experimental and numerical study revealed that the completely overlapped joint performed better in terms of strength resistance, stiffness, ductility, and energy absorption capacity than the conventional gap joints commonly found in typical X-braced jacket framings. The eccentric jacket could also be designed to becoming less stiff, with an inelastic yielding and local buckling of short segment member, so as to better resist the cyclic load generated from intense environmental forces and earthquake. From the design economics, the eccentric jacket provided a more straightforward fabrication with reduced number of welded joints and shorter thicker wall cans than the conventional X-braced jacket. It can therefore be concluded based on the results presented in the study that by designing the short segment member in accordance with strength and ductility requirement,the eccentric jacket substructure supporting the wind turbine could be made to remain stable under gravity loads and to sustain a significantly large amount of motion in the event of rare and intense earthquake or environmental forces, without collapsing.
文摘目的:研究完全腹腔镜胃癌根治术联合overlap吻合术对消化道重建、并发症及患者生活质量的影响。方法:选取2019年6月至2021年12月于蚌埠医学院第一附属医院接受诊治的110例胃癌患者为研究对象。根据不同手术方式分为对照组(传统腹腔镜胃癌根治术,n=60)与观察组(完全腹腔镜胃癌根治术联合overlap吻合术,n=50),比较2组手术疗效及并发症,并采用胃肠道生活质量表(Gastrointestinal Quality of Life,GIQLI)评估生活质量。结果:观察组手术全程用时、消化道重建用时、总失血量均少于对照组(均P<0.05);2组肿瘤大小、淋巴结清扫数比较差异均无统计学意义(均P>0.05)。观察组术后排气时间、流食进食时间、下地时间均少于对照组(均P<0.05);2组住院时间差异无统计学意义(P>0.05)。观察组术后并发症总发生率低于对照组(P<0.05)。随访6个月,2组GIQLI各维度得分及总分均高于出院当天(均P<0.05),观察组GIQLI各维度得分及总分均高于对照组(均P<0.05)。结论:完全腹腔镜胃癌根治术联合overlap吻合术能有效重建消化道,减少并发症,改善生活质量。
文摘近年来,基于张量补全的频谱制图得到了广泛研究.目前用于频谱制图的张量补全算法大多隐含地假设张量具有平衡特性,而对于非平衡张量,难以利用其低秩性估计完整的张量信息,导致补全算法性能受损.本文提出基于重叠Ket增强(Overlapping Ket Augmentation,OKA)和张量列车(Tensor Train,TT)的非平衡频谱制图算法,以解决非平衡张量在应用传统张量补全算法时性能下降的问题.首先使用OKA将低阶高维张量表示为高阶低维张量,在无信息损耗的情况下解决非平衡张量无法利用其低秩性进行张量补全的问题;然后使用TT矩阵化得到较平衡的矩阵,在维度较平衡条件下提高补全算法的精确度;最后利用高阶低维张量的低秩性,使用并行矩阵分解或基于F范数的无奇异值分解(Singular Value Decomposition Free,SVDFree)算法完成张量补全.仿真结果表明,针对非平衡张量,所提方案与现有的张量补全算法相比,可以获得更精确的无线电地图,同时所提SVDFree算法具有更低的计算复杂度.
