Flux Weakening Method at DC-Link Variation of IPMSM for Electric Scooter

Author(s):  
Huiseong Lim ◽  
Wooram Lee ◽  
Kwanyoung Lee ◽  
Dongyoung Shin ◽  
Hoyoung Kim ◽  
...  
FACE ◽  
2021 ◽  
pp. 273250162199244
Author(s):  
Elizabeth M. Boudiab ◽  
Thomas D. Zaikos ◽  
Christopher Issa ◽  
Kongkrit Chaiyasate ◽  
Stephen M. Lu

Electric scooters are an increasingly common and convenient mode of transportation worldwide and have effectively revolutionized the shared micromobility industry. As electric scooter sharing companies have increased in popularity there has been a concomitant increase in the frequency of all electric scooter-related injuries. The purpose of this study is to describe the most up-to-date trends in craniofacial fractures and lacerations related to electric scooter use among all age groups. We queried the National Electronic Injury Surveillance System (NEISS) for craniofacial fractures and lacerations related to e-scooters between 2010 and 2019. We then compared injury trends over time and between time periods before and after 2017 when electric scooter share apps revolutionized micromobility. We compared incidence of injury overall and by day of the week, patient demographics, and case severity based on clinical disposition. We identified an increase in the frequency of craniofacial lacerations and fractures in the 3 years following the introduction of electric scooter share services in 2017 (2017 and 2019), compared to the 3 years before this time (2014-2016). Young adults (18-39 years) were the age group with the greatest interval increase in craniofacial injuries. There was also an increase in number of craniofacial injuries occurring on Mondays and a decrease number occurring on Fridays in the later time period. Finally, patients who presented with electric scooter-related craniofacial injuries in this later time period showed a higher frequency of overnight observation and hospital admission for their injuries. The number of craniofacial injuries secondary to electric scooter use has increased dramatically since the introduction of share services. Craniofacial fractures and lacerations are a common reason for craniofacial or maxillofacial surgery consultation and understanding these patterns of injury will help prepare surgeons for patient care, preventative education, and public advocacy.


2021 ◽  
Vol 92 ◽  
pp. 102709
Author(s):  
Louis A. Merlin ◽  
Xiang Yan ◽  
Yiming Xu ◽  
Xilei Zhao
Keyword(s):  

2015 ◽  
Vol 764-765 ◽  
pp. 374-378 ◽  
Author(s):  
Long Chang Hsieh ◽  
Tzu Hsia Chen ◽  
Hsiu Chen Tang

Traditionally, the reduction ratio of a spur gear pair is limited to 4 ~ 7. For a spur gear transmission with reduction ratio more than 7, it is necessary to have more than two gear pairs. Consider the cost of production, this paper proposes a helical spur gear reducer with one gear pair having reduction ratio 19.25 to substitute the gear reducer with two gear pairs. Based on the involute theorem, the gear data of helical spur gear pair is obtained. According to the gear data, its corresponding engineering drawing is accomplished. This manuscript verify that one spur gear pair also can have high reduction ratio (20 ~ 30).


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