Results 31 to 40 of about 18,205 (168)

The Long and Winding Road: Policy Frictions and the Governance of Ride‐Hailing Platforms in Latin America

open access: yesLatin American Policy, Volume 17, Issue 1, March 2026.
ABSTRACT The rise of ride‐hailing platforms has profoundly transformed urban mobility in Latin America over the past decade. Transportation Network Companies such as Uber, DiDi, Cabify, InDrive, and others operating in the region have affected transportation patterns and intensified debates around labor relations, algorithmic management, regulatory ...
Ronald Sáenz‐Leandro
wiley   +1 more source

中日欧美抗震规范结构影响系数的构成及其对塑性变形需求的影响

open access: yesJianzhu Gangjiegou Jinzhan, 2008
本文对中、日、欧州及美国地震规范地震力计算的结构影响系数的构成进行了分析,认为,美国的结构影响系数中包括了材料的强屈比、超静定结构体系的超强系数以及延性系数;而欧洲的结构影响系数包含了延性系数,对于延性好的结构还允许包含结构体系的超强系数;日本仅包含延性系数;我国也是仅包含延性系数。由于日本采用允许应力设计,还有一个1.4的安全系数,因此比较起来,日本的地震力最大。从结构影响系数的构成看结构在地震作用下产生塑性变形的深度,按照美国规范设计的结构塑性变形要求最高,欧洲次之,我国再次之 ...
童根树, 赵永峰
doaj  

Non‐State Regulators? Civil Society as Extension of the State in a Context of a Regularization Scheme for Undocumented Migrants

open access: yesEuropean Policy Analysis, Volume 12, Issue 1, Winter 2026.
ABSTRACT “Opération Papyrus” was implemented in the Swiss Canton of Geneva between 2017 and 2018 with the aim of granting residence permits to undocumented migrants who met pre‐established criteria. This program serves as an exemplary case of involving nongovernmental actors to facilitate what were originally state‐controlled procedures.
Jan‐Erik Refle   +3 more
wiley   +1 more source

液相外延系统的密封与设备制作

open access: yesGuangtongxin yanjiu, 1987
本文介绍了液湘外延系统设备的密封可靠性与真空度对外延片质量的影响。按要求设计、制作了操作方便、真空度高、密封性好、全硬接液相外延设备。
王皎
doaj  

Synergistic Anode/Cathode Optimization Engineering by Hierarchical Porous N‐Doped Carbon Fibers for Efficient Zinc Batteries

open access: yesRare Metals, Volume 45, Issue 2, February 2026.
ABSTRACT The poor Zn chemistry of Zn metal anode and sluggish reaction kinetics of cathodes at high mass loadings are two crucial issues for hindering the application of aqueous Zn‐ion batteries (AZIBs). Herein, the hierarchical porous N‐doped carbon fibers (HPNCFs) were proposed to simultaneously optimize the reversibility of Zn plating/stripping of ...
Song Yang   +6 more
wiley   +1 more source

湿污表面直流局部电弧的演变过程

open access: yesDianci bileiqi, 2017
飘弧和弧道在湿污表面沿泄漏距离的延伸是局部电弧演变的主要环节。利用高速摄像机观测了不同极性直流局部电弧在湿污表面的演变过程,并从气体放电理论分析和解释了出现上述现象的原因。观测结果表明,负极性电弧比正极性电弧飘弧更严重,且负极性电弧延伸速率高于正极性电弧;电弧延伸过程中,正极性电弧更容易出现分叉和并列弧道的现象,负极性电弧更易出现尖状的头部。负极性电弧更易飘弧是由于电弧与污层之间的流注更易发展,使负极性电弧和污层之间更易保持良好的导电通道,所以飘弧更易维持,也更严重;正极性电弧端部紧贴污层表面 ...
金巧芳, 李亚伟
doaj  

The effect of moxisylyte hydrochloride in the symptomatic treatment of benign prostatic hyperplasia [PDF]

open access: yes, 1989
α1遮断剤の1つである塩酸モキシシリト(90 mg/日, 4週間)を前立腺肥大症患者22例に投与した.1)自覚症状では, 残尿感(53%)遷延性排尿(74%), ぜん延性排尿(63%), 尿線の状態(67%), 腹圧排尿(58%)に改善を認めた.2)副作用は4例に認められ, そのうち, めまいを呈した1症例で投与を中止した.血圧低下はほとんど認められなかった.3)全般改善度に概括安全度を加味した本剤の有用度は, 有用以上41%, やや有用以上77%であったThe clinical ...
久保, 星一   +4 more
core  

大高宽比矩形钢管混凝土柱压弯性能研究

open access: yesJianzhu Gangjiegou Jinzhan
为了研究大高宽比矩形钢管混凝土柱的压弯性能,对大高宽比钢管混凝土短柱进行偏压试验并结合有限元模拟补充了4组试件进行对比,包括不同偏心率、高宽比、钢管壁厚度、截面尺寸情况下柱性能的对比分析。最后参考常用的4本国内外规范进行柱承载力计算,对比并判断现有规范是否适用。结果表明:试件破坏模式均为长边鼓曲,当荷载小于极限承载力的80%时,横截面高度上的应变分布服从平截面假定;随着偏心率增大,柱延性提升,在偏心率超过0.205后,柱延性开始下降;随着壁厚增加,柱延性提升,在壁厚达到8 mm后,柱延性开始下降 ...
陈安英   +4 more
doaj   +2 more sources

The Dependence of Properties on Structural Features in Macro/Micro Levels for PBF‐LB Fabricated Porous NiTi Alloy

open access: yesRare Metals, Volume 45, Issue 2, February 2026.
ABSTRACT Porous NiTi alloys are widely used in biomedical and engineering fields. Using the PBF‐LB technique, the TPMS and Voronoi porous parts with a porosity of ∼67% and a minimum feature size of 0.15 ± 0.02 mm were fabricated. Although the bulk sample fabricated with the same parameters is defect‐free, μ‐CT reconstruction on the porous sample ...
Wen‐Hao Zeng   +7 more
wiley   +1 more source

Designing High‐Strength and High‐Ductility Cast Mg–Zn–Al–Mn–Sn Alloys via τ‐Mg32(Al,Zn)49 Phase Tuning and Twin Boundary Toughening Optimisation

open access: yesRare Metals, Volume 45, Issue 2, February 2026.
ABSTRACT Achieving a simultaneous enhancement of strength and ductility remains a critical bottleneck for the large‐scale and cost‐effective engineering application of magnesium alloys. In this work, guided by first‐principles calculations, we tailored the τ‐Mg32(Al,Zn)49 phase and optimised twin boundary, thereby designing and successfully ...
Yun‐Xuan Zhou   +8 more
wiley   +1 more source

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