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Position Control of Flexible Joint Carts Using Adaptive Generalized Dynamics Inversion

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Computers, materials & Continua 2022年第3期70卷 4691-4705页

作者： Ibrahim m.mehedi mohd Heidir mohd Shah Soon Xin Ng Abdulah Jeza Aljohani mohammed El-Hajjar muhammad moinuddin Department of Electrical and Computer Engineering(ECE) King Abdulaziz UniversityJeddah21589Saudi Arabia Center of Excellence in Intelligent Engineering Systems(CEIES) King Abdulaziz UniversityJeddah21589Saudi Arabia Next Generation Wireless Research Group University of SouthamptonUK

This paper presents the design and implementation of Adaptive Generalized Dynamic Inversion(Agdi)to track the position of a Linear Flexible Joint Cart(LFJC)system along with vibration suppression of the flexible *** proposed Agdi control law will be comprised of two control *** baseline(continuous)control law is based on principle of conventional gdi approach and is established by prescribing the constraint dynamics of controlled state variables that reflect the control *** control law is realized by inverting the prescribed dynamics using dynamically scaledmoore-Penrose generalized *** boost the robust attributes against system nonlinearities,parametric uncertainties and external perturbations,a discontinuous control law will be augmented which is based on the concept of sliding mode *** discontinuous control law,the sliding mode gain is made adaptive in order to achieve improved tracking performance and chattering *** closed-loop stability of resultant control law is established by introducing a positive define Lyapunov candidate function such that semi-global asymptotic attitude tracking of LFJC system is *** computer simulations followed by experimental investigation will be performed on Quanser’s LFJC system to authenticate the feasibility of proposed control approach for its application to real world problems.

关键词： Adaptive control generalized dynamic inversion moore-penrose generalized inverse sliding mode control lyapunov stability semi-global asymptotic stability

OCULAR BLOOD FLOW EVALUATION (POBF AND gdi) IN INJURED AND HEALTHy FELLOW EyES

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国际眼科杂志 2003年第1期3卷 39-39页

作者： E.martini m.Guiducci G.P.Scarale G.m.Cavallini University of modena and Reggio Emilia Neuropsychosensorial Sciences Department Ophthalmology Section ItalyUniversity of Modena and Reggio Emilia Neuropsychosensorial Sciences Department Ophthalmology Section ItalyUniversity of Modena and Reggio Emilia Neuropsychosensorial Sciences Department Ophthalmology Section ItalyUniversity of Modena and Reggio Emilia Neuropsychosensorial Sciences Department Ophthalmology Section Italy

Purpose: To assess if injured eyes develop ocular blood flow disturbances that may contribute to development of traumatic glaucoma. materials and methods: 25 patients hospitalized for eye injury and elevated IOP were evaluated 24 months after the trauma. All injured and fellow eyes underwent IOP measure, visual field (HfaII, Central 30/2SITA), pulsatile ocular blood flow analysis (POBF, OBF Labs UK), CDI examination (PSV, EDV, and RI) of Ophthalmic Artery, Central Retinal Artery, Short Posterior Ciliary Arteries. Results: IOP was significantly higher in injured eyes (15.1 vs 13.0±2.7mmHg) (P= 0,01), but only 2 eyes (8.8%) were under medical treatment POBF values were significantly lower in injured eyes: 11,25 μl/s in traumatised eyes and 15,40 μl/s in fellow eyes (P = 0.002). Resistivity Index (RI) of all investigated retrobulbar vessels was very significantly higher in injured eyes than in fellow eyes (P= 0.0001). There is no significant correlation between IOP and ocular blood flow disturbances.

关键词：眼损伤健康眼眼内血流 POBF CDI 彩色多普勒显像敏感性

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新型汽油机双喷嘴系统喷雾概念的开发

汽车与新动力 2019年第1期2卷 50-54页

作者： [日]H.Shibata T.mizobuchi m.Iwamuro A.Koda H.Omura 武涛(译) 不详

为了应对全球环境和能源安全问题,汽油直接喷射(gdi)系统是主要发展热点。与此同时,深入开发多点燃油气道喷射系统(mPI),使这种简单可靠的燃烧系统能适应全球油品是非常重要的。在新兴国家的汽车市场,特别是A级和B级车有一定的mPI发动... 详细信息

为了应对全球环境和能源安全问题,汽油直接喷射(gdi)系统是主要发展热点。与此同时,深入开发多点燃油气道喷射系统(mPI),使这种简单可靠的燃烧系统能适应全球油品是非常重要的。在新兴国家的汽车市场,特别是A级和B级车有一定的mPI发动机需求。重点研究了mPI系统开发的关键技术,即在低温条件下减少燃油湿壁,以及在大负荷工况下通过燃油气化最大限度地降低混合气的温度(防止爆燃)。提出了一种新mPI双喷嘴系统,不仅保留了mPI系统均质混合气的优点,而且增加了直接进入燃烧室的喷雾数量,从而获得了类似gdi的部分优点。这种mPI双喷嘴系统需要有更好的雾化效果和进气气流的稳定性。开发了独特的雾化技术并优化了喷雾形态,以此改善了雾化效果和相对进气气流的稳定性,实现了开阀喷射的收益。

关键词：双喷系统多点喷射汽油机燃油喷射系统颗粒排放

发动机颗粒排放和再生频率对汽油机颗粒捕集器效率的影响

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汽车与新动力 2021年第2期4卷 53-59页

作者： [德]F.ADAm [德]J.OLFERT [德]K.F.WONG [德]S.KUNERT [德]J.m.RICHTER 武涛(译) 不详

汽油机颗粒捕集器(GPF)是1种重要的排放后处理系统,能使汽油缸内直喷(gdi)发动机达到现行的排放标准。现行标准规定的非挥发性颗粒物直径大于23.0nm。然而,随着排放法规的逐渐严格,GPF过滤效率需要进一步提高,并且可能会对直径低至10.0n... 详细信息

汽油机颗粒捕集器(GPF)是1种重要的排放后处理系统,能使汽油缸内直喷(gdi)发动机达到现行的排放标准。现行标准规定的非挥发性颗粒物直径大于23.0nm。然而,随着排放法规的逐渐严格,GPF过滤效率需要进一步提高,并且可能会对直径低至10.0nm的非挥发性颗粒物排放进行限制。GPF过滤效率取决于在发动机运行期间聚集在GPF上的炭烟量。在车辆运行期间,当排气温度足够高且含有足够的氧气时,GPF通常是“被动”再生的。研究了发动机废气颗粒数排放(PN)和GPF再生频率对GPF过滤效率的影响。采用2种GPF技术,分别在2台发动机台架上进行了测试,并匹配2台量产车在转毂台架上进行了测试。试验发动机颗粒物排放数量分布的带宽很广,几乎达到1个数量级,更具实际排放代表性。GPF的过滤效率通过符合规定的颗粒数系统(非挥发性颗粒直径大于23.0nm、下限为2.5nm)的粒子计数器,以及差分迁移率光谱仪进行测量计算获得。结果显示,GPF有规律地达到可再生的条件,并且GPF的平均驾驶循环过滤效率高度依赖于发动机颗粒物排放量;当发动机颗粒物排放量增加约1个数量级时,GPF的过滤效率显著提高。研究表明,根据发动机颗粒物排放量选择合适的GPF技术非常重要。

关键词：颗粒物排放汽油机颗粒捕集器过滤效率尺寸分布缸内直喷汽油机

缸内直喷汽油机进一步降低燃油消耗率的低节流气门技术的评估和比较

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汽车与新动力 2019年第5期2卷 42-48页

作者： P.FREELAND[英] G.JONES[英] m.E.KASSEm[英] R.KAISER[英] R-S.CHEN L-W.HUANG 高英英(译) 不详

阐述了1种采用气门技术降低燃油耗的方法,能够使汽油机效率等同于柴油机效率。通过全参数可变进气系统并结合宽广运行范围的凸轮相位器,相对提高了内燃机效率,而且该气门技术能够提供零气门升程,实现停缸功能。原型概念机试验结果显示... 详细信息

阐述了1种采用气门技术降低燃油耗的方法,能够使汽油机效率等同于柴油机效率。通过全参数可变进气系统并结合宽广运行范围的凸轮相位器,相对提高了内燃机效率,而且该气门技术能够提供零气门升程,实现停缸功能。原型概念机试验结果显示了进气门早关、气门重叠和停缸的协同工作,以及不同工况下这种协同工作的局限性。论证了升功率超过105kW、平均有效压力为0.2 mPa、空燃比λ=1.0工况下燃油消耗率少于300g/(kW·h)的可量产的2.0L中央直喷汽油机(gdi)的潜力。强制点火汽油机采用预混当量比燃烧,效率与柴油机效率相当,燃烧更为清洁,后处理过程更为简单、稳定。

关键词：低节流气门缸内直喷燃油消耗率可调气门