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Railway Engineering Science 2023年第2期31卷 162-171页

作者： n.bosso Matteo Magelli n.Zampieri Department of Mechanical and Aerospace Engineering Politecnico di TorinoC.so Duca degli Abruzzi 2410129 TurinItaly

The present paper shows the development of a strategy for the calculation of the air brake forces of European freight trains. The model is built to upgrade the existing Politecnico di Torino longitudinal train dynamics(LTD) code LTDPoliTo, which was originally unable to account for air brake forces. The proposed model uses an empirical exponential function to calculate the air brake forces during the simulation, while the maximum normal force on the brake friction elements is calculated according to the indication of the vehicle braked weight ***, the model does not require to simulate in detail the fluid dynamics in the brake pipe nor to precisely know the main parameters of the braking system mounted on each vehicle. The model parameters are tuned to minimize the difference between the braking distance computed by the LTDPoliTo code and the value prescribed by the UIC544-1 leaflet in emergency braking operations. Simulations are run for different configurations of freight train compositions including a variable number of Shimmns wagons trailed by an E402B locomotive at the head of the train, as suggested in a reference literature paper. The results of the proposed method are in good agreement with the target braking distances calculated according to the international rules.

关键词： Railway brake modelling Emergency braking UIC braking system Braked weight Longitudinal train dynamics

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Simulation of wheel and rail profile wear:a review of numerical models

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Railway Engineering Science 2022年第4期30卷 403-436页

作者： n.bosso M.Magelli n.Zampieri Department of Mechanical and Aerospace Engineering Politecnico Di TorinoC.so Duca degli Abruzzi 2410129 TurinItaly

The development of numerical models able to compute the wheel and rail profile wear is essential to improve the scheduling of maintenance operations required to restore the original profile *** work surveys the main numerical models in the literature for the evaluation of the uniform wear of wheel and rail *** standard structure of these tools includes a multibody simulation of the wheel-track coupled dynamics and a wear module implementing an experimental wear ***,the models are classified according to the strategy adopted for the worn profile update,ranging from models performing a single computation to models based on an online communication between the dynamic and wear ***,the most common strategy nowadays relies on an iteration of dynamic simulations in which the profiles are left unchanged,with co-simulation techniques often adopted to increase the computational *** is still needed to improve the accuracy of the current *** experimental campaigns should be carried out to obtain refined wear coefficients and models,while strategies for the evaluation of both longitudinal and transversal wear,also considering the effects of tread braking,should be implemented to obtain accurate damage models.

关键词： Wear Wheel and rail profiles Wheel-rail contact Railway vehicle dynamics Multibody simulation Co-simulation

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The effectiveness of different wear indicators in quantifying wear on railway wheels of freight wagons

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Railway Engineering Science 2024年第3期32卷 307-323页

作者： Philipe Augusto de Paula Pacheco M.Magelli Matheus Valente Lopes Pedro Henrique Alves Correa n.Zampieri n.bosso Auteliano Antunes dos Santos Federal Institute of the Southeast of Minas Gerais(IF Sudeste MG) Técnico PanamáStreet 45Santos DumontMG 36246-311Brazil Railway Laboratory(Lafer) Universidade Estadual de Campinas(UNICAMP)Mendeleyev Street 200CampinasSP 13083-872Brazil Department of Mechanical and Aerospace Engineering Politecnico Di TorinoC.so Duca degli Abruzzi 2410129 TurinItaly

Railway infrastructure relies on the dynamic interaction between wheels and rails;thus,assessing wheel wear is a critical aspect of maintenance and *** paper focuses on the wheel-rail wear indicator T-gamma(Tγ).Amidst its use,it becomes apparent that Tγ,while valuable,fails to provide a comprehensive reflection of the actual material removal and actual contact format,which means that using only Tγas a target for optimization of profiles is not *** this work,three different freight wagons are evaluated:a meter-gauge and a broad-gauge heavy haul vehicles from South American railways,and a standard-gauge freight vehicle operated in Europe,with different axle loads and dissimilar new wheel/rail *** vehicles are subjected to comprehensive multibody simulations on various *** simulations aimed to elucidate the intricate relationship between different wear indicators:Tγ,wear index,material removal,and maximum wear depth,under diverse curves,non-compensated lateral accelerations(A_(nc)),and *** findings showed a correlation of 0.96 between Tγand wear depth and 0.82 between wear index and material removed for the outer *** the results,the Tγis better than the wear index to be used when analyzing wear depth while the wear index is more suited to foresee the material *** results also show the low influence of A_(nc)on wear index and Tγ.By considering these factors together,the study aims to improve the understanding of wheel-rail wear by selecting the best wear analysis approaches based on the effectiveness of each parameter.

关键词： Wear index Wear volume Wear modeling Dynamic simulation

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Locally advanced nasopharyngeal carcinoma:Current and emerging treatment strategies

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World Journal of Clinical Oncology 2011年第12期2卷 377-383页

作者： Francesco Perri Davide bosso Carlo Buonerba Giuseppe Di Lorenzo Giuseppina Della Vittoria Scarpati Oncology Division Division INT Fondazione“G.Pascale”80131 NaplesItaly Oncology and Rare Cancer Center FedericoⅡUniversity80131 NaplesItaly

Although nasopharyngeal carcinoma(nPC)is a widespread malignant tumor,it is particularly frequent in Southeast *** T1 tumors can be effectively controlled with exclusive radiotherapy,this treatment modality is insufficient for most nPC patients,who present with locally advanced disease at *** fact,for stages ranging from T2b n0 to T4 n3,definitive scientific evidence supports the use of concurrent platinum-based chemotherapy with standard external beam *** treatment approach has shown a statistically significant advantage in terms of overall survival,with respect to radiotherapy *** trials have also investigated the use of neoadjuvant and adjuvant chemotherapy in combination with radiotherapy or *** compounds,anthracyclines and taxanes are among the chemotherapy agents *** review focuses on the clinical results obtained in the field of adjuvant/concurrent/neoadjuvant chemotherapy for locally advanced nPC,for which exclusive concurrent chemo-radiotherapy currently represents the standard treatment approach.

关键词： Chemotherapy nasopharyngeal carcinoma Radiotherapy Treatment

John 5给初学者与专业吉他手的实用建议

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乐器 2024年第7期 110-111页

作者： Joe bosso Slowly(译) 不详

John 5是一位精通多种风格的吉他大师,曾与Lynyrd Skynyrd、David Lee Roth、Rick Springf ield合作演出,现在更是加入到M?tley Crüe,他为乐手提供的指导远不止练习方法这么简单。任何能将乡村风格的chicken pickin'技法与金属速弹相... 详细信息

John 5是一位精通多种风格的吉他大师,曾与Lynyrd Skynyrd、David Lee Roth、Rick Springf ield合作演出,现在更是加入到M?tley Crüe,他为乐手提供的指导远不止练习方法这么简单。任何能将乡村风格的chicken pickin'技法与金属速弹相结合的吉他手,绝不仅仅是“一招吃天下”。在他的职业生涯中,John 5将多样性作为自己的一张名片,他提供的吉他服务受到了众多艺术家的青睐,其中包括***、Marilyn Manson、Wilson Phillips、Lynyrd Skynyrd、David Lee Roth、Rick Springfield、Salt-n-Pepa等。

关键词：吉他手合作演出实用建议乡村风格练习方法多种风格职业生涯

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Wet and Dry Season Effects on Select Soil nutrient Contents of Upland Farms in north Bank Region of the Gambia

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Open Journal of Soil Science 2016年第3期6卷 45-51页

作者： Ebrima Sonko Daniel n. Tsado Sidat Yaffa Appollonia A. Okhimamhe Julia Eichie WASCAL Coordinating Secretariat Federal University of Technology Bosso Campus Minna Nigeria School of Agriculture and Agricultural Technology Federal University of Technology Minna Nigeria School of Agriculture and Environmental Sciences University of the Gambia Brikama Campus Brikama The Gambia

The study was conducted in three villages of north Bank Region of the Gambia in 2013 and 2014. We examined wet and dry season effects on select soil nutrient contents of upland farms in north Bank Region of the Gambia. The objective was to evaluate changes in soil nutrient contents in both wet and dry seasons. Soil samples were collected from three RCBD upland fields with three replications at a depth of 0 - 15 cm and analyzed for pH, Soil Organic Carbon (SOC), and soil moisture content. The gravimetric method of moisture estimation was used. The results showed that soil moisture content, soil Tn, and soil pH are significantly different (P ng the two seasons. There was no significant difference in SOC between the two seasons in the study area. The study concluded that soil nutrients were more readily available during the wet season than during the dry season probably because there is more soil moisture available in the wet season that facilitates soil nutrient release. The study concludes that soil moisture has to be available in order for some select soil nutrients to be released for plant uptake.

关键词： Soil nutrients Wet Season Dry Season pH