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Rotary-scaling fine-tuning (RSFT) method for optimizing railway wheel profiles and its application to a locomotive

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Railway Engineering Science 2020年第2期28卷 160-183页

作者： Yunguang Ye Yayun Qi Dachuan Shi Yu Sun Yichang Zhou Markus hecht Institute of Land and Sea Transport Systems Technical University of Berlin10587 BerlinGermany State Key Laboratory of Traction Power Southwest Jiaotong UniversityChengdu 610331China College of Transportation Science and Engineering Nanjing Tech UniversityNanjing 210009China

The existing multi-objective wheel profile optimization methods mainly consist of three sub-modules:(1)wheel profile generation,(2)multi-body dynamics simulation,and(3)an optimization *** the first module,a comparably conservative rotary-scaling finetuning(RSFT)method,which introduces two design variables and an empirical formula,is proposed to fine-tune the traditional wheel profiles for improving their engineering *** the second module,for the TRAXX locomotives serving on the Blankenburg–Rubeland line,an optimization function representing the relationship between the wheel profile and the wheel–rail wear number is established based on Kriging surrogate model(KSM).For the third module,a method combining the regression capability of KSM with the iterative computing power of particle swarm optimization(PSO)is proposed to quickly and reliably implement the task of optimizing wheel ***,with the RSFT–KSM–PSO method,we propose two wear-resistant wheel profiles for the TRAXX locomotives serving on the Blankenburg–Rubeland line,namely S1002-S and *** S1002-S profile minimizes the total wear number by 30%,while the S1002-M profile makes the wear distribution more uniform through a proper sacrifice of the tread wear number,and the total wear number is reduced by 21%.The quasi-static and hunting stability tests further demonstrate that the profile designed by the RSFT–KSM–PSO method is promising for practical engineering applications.

关键词： Wheel profile optimization Wear reduction Rotary-scaling fine-tuning Particle swarm optimization Kriging surrogate model

Public Charging Infrastructure in Germany–A Utilization and Profitability Analysis

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Journal of Modern Power Systems and Clean Energy 2022年第6期10卷 1750-1760页

作者： Benedict J.Mortimer Amandus Dominik Bach Christopher hecht Dirk Uwe Sauer Rik W.De Doncker Institute for Power Generation and Storage Systems at the E.ON Energy Research Center RWTH Aachen UniversityAachenGermany

The current increase in the number of electric vehicles in Germany requires an adequately developed charging *** numbers of public and semi-public charging stations are necessary to ensure sufficient coverage of charging *** order to make the installation worthwhile for the mostly private operators as well as public ones,a sufficient utilization is *** paper gives an overview of the differences in the utilization across the public charging infrastructure in *** this end,a dataset on the utilization of 21164 public and semi-public charging stations in Germany is *** installation and operating costs of various charging stations are modeled and economically evaluated in combination with the utilization *** is shown that in 2019-2020,the average utilization in Germany was rather low,albeit with striking regional *** consider future scenarios allowing the regional development forecasting of economic *** is demonstrated that a growth in electric mobility of 20%-30%per year leads to a large number of economically feasible charging parks in urban agglomeration areas.

关键词： Charging infrastructure charging station utilization electromobility economic analysis

Hemoglobin Adducts as Biomarkers of Exposure to and metabolic Activation of Carcinogenic Tobacco-Specific Nitrosamines

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Biomedical and Environmental Sciences 1991年第1期4卷 93-103页

作者： STEPHEN S.hecht STEVEN G.CARMELLA SHARON E.MURPHY Dana Road American Health Foundation ValhallaDana Road American Health Foundation ValhallaDana Road American Health Foundation Valhalla New York 10595New York 10595 New York 10595

The carcinogenic tobacco-specific nitrosamines N-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-l-(3-pyridyl)-l-butanone (NNK) form hemoglobin adducts in laboratory animals and humans. These adducts release 4-hydroxy-l-(3-pyridyl)-l-butanone (HPB) upon mild base hydrolysis. HPB released from human hemoglobin can be quantified by gas chromatography-mass spectrometry. It is the only available biochemical marker for determination of exposure to, and metabolic activation of, carcinogens present only in tobacco. Levels of HPB were highest in snuff-dippers, followed by smokers and nonsmokers. Large interindividual variations in adduct levels were observed. The relationship between HPB levels in globin and DNA of rats treated with NNK has been investigated in order to aid in interpretation of the data from humans. These studies have provided the initial database for understanding the metabolic activation of tobacco-specific nitrosamines in humans.

关键词： Hemoglobin Adducts as Biomarkers of Exposure to and metabolic Activation of Carcinogenic Tobacco-Specific Nitrosamines

电动车尾门电动推杆用低音调齿轮的开发与验证

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同济大学学报（自然科学版） 2021年第S01期49卷 108-113页

作者：任亚雄 hecht Matthias ADAMS Christian MELZ Tobias 达姆施塔特工业大学系统可靠性、自适应结构和机械声学研究组德国达姆施塔特64287 弗劳恩霍夫结构耐用性和系统可靠性研究所德国达姆施塔特64289

高速电动机目前被广泛用于汽车自主驾驶系统。由于高速电动机采用小质量设计,因此为了使转速和输出扭矩达到目标值,通常将渐开线齿轮组和它配套使用。然而,传统的渐开线齿轮在工作中噪声较大,因此一种新型的具有不规则轮齿设计的低音调(... 详细信息

高速电动机目前被广泛用于汽车自主驾驶系统。由于高速电动机采用小质量设计,因此为了使转速和输出扭矩达到目标值,通常将渐开线齿轮组和它配套使用。然而,传统的渐开线齿轮在工作中噪声较大,因此一种新型的具有不规则轮齿设计的低音调(Low⁃Tone)齿轮被开发,以减少齿轮传动装置的噪声。通过优化算法,开发设计了一种Low⁃Tone齿轮,并应用于一个驱动电动车尾门启闭的电动推杆系统。之后在该系统运行期间,对使用Low⁃Tone齿轮和使用传统齿轮所产生的声压进行测量对比。结果表明,Low⁃Tone齿轮对于噪声有较好的抑制作用,其优势特别体现在音调特性方面。

关键词：低音调齿轮噪声降低音调特性

Large Mammals Once Dined on Dinosaurs

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当代外语研究 2005年第3期 34-35页

作者： Jeff hecht 浦江红

中生代哺乳动物吃恐龙?这在化石发现前是无法想象的事情。但确凿的化石证据大大改变了以往人们对中生代哺乳动物委屈地生活在恐龙阴影下的印象,原来它们之中也有个体比小型恐龙还大,甚至可能是行走于光天化日之下,能够吞噬小恐龙的肉食... 详细信息

中生代哺乳动物吃恐龙?这在化石发现前是无法想象的事情。但确凿的化石证据大大改变了以往人们对中生代哺乳动物委屈地生活在恐龙阴影下的印象,原来它们之中也有个体比小型恐龙还大,甚至可能是行走于光天化日之下,能够吞噬小恐龙的肉食类哺乳动物。

关键词：中生代哺乳动物 Large Mammals Once Dined on Dinosaurs

Past, Present and Future: Urgency of Dealing with Climate Change

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Atmospheric and Climate Sciences 2014年第5期4卷 779-795页

作者： Alan D. hecht Office of Research and Development US Environmental Protection Agency Washington DC USA

This paper gives an historic perspective on 10 critical phases and actions in advancing an understanding of climate change and taking appropriate domestic and international action. Credit goes to atmospheric scientists for their committed efforts to understand, model and measure the impacts of climate change. Today, greenhouse gases are at a record level and little doubt remains that greenhouse gases (GHG) warm the atmosphere and that human-made climate change is real. Recognizing the urgency of responding to climate change, the 2013 US Climate Action Plan aims to cut carbon emissions and prepare to deal effectively with the economic, social, and environmental impacts of climate change. Many US states, Tribes, and local communities have also begun to take action to reduce GHG emissions and adapt to the impact of climate change, especially on disadvantaged communities. While recognition of the urgency of action on climate change is growing in government and in large parts of the business and financial sector, it has taken over 40 years to get to this point. While an understanding of the reality and impact of climate change has grown, significant efforts to reduce the concentration of greenhouse gases in the atmosphere and stabilize global warming have not occurred. The problem that society faces is not the absence of scientific knowledge, but rather the need to reduce GHG emissions and create resilient and adaptive responses to climate change. This paper concludes that future successes will need more effective collaboration between government, business, and society to address climate change and greater public understanding of the impacts of climate change on human health and economic well-being.

关键词： Climate Change Atmospheric Science Resilience Climate Adaptation

Local Conformational Constraint of Firefly Luciferase Can Affect the Energy of Bioluminescence and Enzyme Stability

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CCS Chemistry 2022年第5期4卷 1695-1707页

作者： Chao Zhang Xiaoguang Bai Shengxi Chen Larisa M.Dedkova Sidney M.hecht Biodesign Center for Bioenergetics Arizona State UniversityTempeArizona 85287 School of Molecular Sciences Arizona State UniversityTempeArizona 85287

Conformational dynamics contribute importantly to enzyme catalysis,such that targeted conformational constraint may affect *** luciferases undergo extensive structural change during catalysis;key residues form a hydrophobic pocket,excluding water and enabling maximally energetic light *** mutants almost always luminesce at longer wavelengths(lower energy)than the wild *** constraint,using dipeptide analogue 3 at a position critical for optimized excited state structure,produced luciferase emission at a shorter wavelength by∼10 ***,introduction of conformationally constrained analogues 4,5,or 7 afforded luciferases emitting at longer wavelengths,while a related unconstrained luciferase(analogue 6)exhibited wild-type *** constrained luciferases tested were more stable than the wild *** modeling demonstrated that the“inside”or“outside”orientation of the conformationally constrained dipeptide led to the shorter or longer emission wavelength,*** broadly,these results suggest that local conformational constraint can control specific elements of enzyme behavior,both in vitro and in *** represents the first example of studying enzyme function by introducing conformationally constrained dipeptides at a specific protein *** principles discovered here in luciferase modification will enable studies to control the wavelength emission and photophysical properties of modified luciferases.

关键词： genetic code reprogramming modified ribosomes conformational constraint luciferase bioluminescence and stability protein modeling