• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.3B no.2
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• pp.90-96
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• 2003

This paper deals with the design and the characteristic analysis of a coreless axial flux permanent magnet (AFPM) motor. Because a direct-drive wheel motor is easily derived from it, the AFPM motor is very suitable for application in an electric scooter. Compared to a conventional motor of the same size and weight, the AFPM motor is proven to have more power and torque per unit weight. In this paper, an AFPM coreless motor with a double-sided rotor disk equipped with Nd-Fe-B rare earth magnets is designed and a prototype of the motor is manufactured, which will be properly applied for the low-speed, and high-torque direct drive required for the electric scooter. The manufactured prototype of the motor has a rating of 300W, 510rpm, 5.6Nm, and 85% efficiency.

• International journal of advanced smart convergence
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• v.8 no.1
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• pp.58-64
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• 2019

In recent years, small mobile devices called personal mobility or smart mobility have attracted attention. Personal mobility refers to electric-driven personal transportation that can travel at close range and medium distance, including small electric vehicles, electric bicycles, electric motorcycles and electric scooters. Most of the electric scooters used in Korea are mainly imported from China. This is due to the fact that the price competitiveness of major components of electric scooters is owned in China. At this point, the domestic research direction is preferable for the composition and design of the electric scooter body rather than cost reduction for the components. In this study, we propose a new model of portable folding structure that is easy to use for electric scooters, which are personal vehicles using electric energy. We also made a prototype for practical use.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.3
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• pp.98-105
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• 2012

Recently, most of the countries started to regulate the emission of vehicle because of the global warming. The engine scooter is also one of the factor which cause the pollution. The hybrid system of a vehicle has many advantages such as fuel saving and emission reduction. The purpose of this study is to choose optimal size of engine, motor and battery for hybrid scooter system using Dynamic programming. The dynamic programming is an effective method to find an optimal solution for the complicated nonlinear system, which contains various constraints of control variables. The power source size of hybrid scooter was chosen through the backward simulator using dynamic programming. From the analysis, we choose the optimal size of each power source. To verify the optimal size of the power source, the Forward simulation was carried out. As a result, the fuel efficiency of hybrid scooter has significantly increased in comparison with that of engine scooter.

• Journal of Trauma and Injury
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• v.35 no.4
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• pp.232-239
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• 2022

Purpose: The recent increase in electric scooter (e-scooter) use has been accompanied by an increase in injuries from e-scooter-related accidents. Studies have reported that most such injuries are minor, and physicians may therefore underestimate the severity of such injuries. This study investigated the types and severity of injuries caused by isolated e-scooter accidents (i.e., those that did not involve colliding with other cars or falling from heights). Methods: This prospective observational study was conducted from May to December 2021 at Dankook University Hospital tertiary medical center. The demographic data of patients injured in isolated e-scooter-related accidents were collected. All injuries were categorized by body part. Results: Fifty eligible patients visited our emergency department during the study period. Of these, 76% were categorized as nonemergency, and 62% were discharged after initial evaluation and treatment at the emergency department. Another 10% were admitted to the intensive care unit (ICU) and 18% to the ward, with nine patients receiving at least one operation. The average hospital stays were 2.4 days in the ICU and 9 days in the ward. One death occurred due to traumatic brain injury (overall mortality rate, 2%). Multiple fractures of the left third through ninth ribs combined with lung laceration and fractures of T12 and L4 were noted. Conclusions: Various types and severities of injuries can occur in isolated e-scooter accidents. While most such injuries are minor, some will require ICU admission or surgery, and deaths can occur. Physicians should not underestimate the severity of such injuries.

• The Transactions of the Korean Institute of Power Electronics
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• v.16 no.2
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• pp.130-136
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• 2011

This paper presents the torque control algorithm of a permanent magnet synchronous motor(PMSM) for an electric scooter. The volume of the in-wheel type motor is restricted due to the complicated mechanical structure in wheel of an electric scooter, so the hall sensors instead of resolver and encoder for the rotor position sensors are installed. In this paper, the rotor speed and position are estimated from the speed estimator for vector control of a PMSM with hall sensors. The motor starts to rotate at standstill in BLDC mode with 120 degree conduction. After start up, the operating mode is changed to the vector control with maximum torque per ampere(MTPA) operation at low speeds and flux weakening control at high speeds. The performance of the proposed control algorithm is verified through the experiment in the electric scooter.

• The Journal of the Korea institute of electronic communication sciences
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• v.16 no.6
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• pp.1323-1328
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• 2021

In this paper, we present a medical electric scooter sharing platform for the transportation vulnerable who are experiencing difficulties and inconveniences in moving. The proposed medical electric scooter sharing platform for the transportation vulnerable includes basic mobile rental, return, and functions that incorporate the IOT technology of the currently operating personal mobility sharing platform. The safety function has been strengthened. The medical electric scooter sharing platform for the transportation vulnerable stores driving data on the server in real time through GPS, and strengthens the alarm and call function in advance of an accident to enable rapid SOS processing. By making the quick contact and responding to the situation, people with disabilities can drive safely and comfortably.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.10a
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• pp.847-849
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• 2009

Usually, after the decisions of the performance and range in the commercial vehicle, it is designed the ratings of the electric and mechanical elements for the vehicles. In this paper, the given performance and driving conditions, which are the maximum velocity, mileage, total weight of the normal gasoline scooter, battery type and size, and so on, are analysed for the design of the electric scooter. The maximum rotational speed and needed torque values of the electric motor which is substituted for the gasoline engine are calculated. These values can help to calculate the rating of the electric motor. In the calculation to obtain the torque and speed values, battery discharge and the running resistances are considered. We can decide the electric motor current value from the torque and speed values. The electric motor current values, which are significant parameter to decide the motor type and dimensions and characteristics of the electric motor, are decided by numerical simulation by the above conditions.

• Archives of Plastic Surgery
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• v.49 no.1
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• pp.50-54
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• 2022

Background In recent years, the number of people riding stand-up electric scooters in South Korea has increased rapidly. This study analyzed the facial injury patterns associated with stand-up electric scooter-related trauma in patients who visited our emergency center. Methods In this retrospective review, we collected data from patients who had visited our emergency center for stand-up electric scooter-related trauma between January 1, 2018 and December 31, 2020. Results The average age of the patients was 26.7 years. Of the 73 patients, 47 were male and 26 were female, highlighting a male predominance. Seven patients were injured after alcohol consumption. None of the patients had worn helmets. Additionally, upon comparing the frequency of facial injuries according to the quarter of the year, the facial injury rate was higher in the second and third quarters than in the first and fourth quarters. Facial soft tissue injuries were classified into facial cosmetic subunits and analyzed according to their location. The highest number of injuries was on the chin (n=18, 20.9%). Of the 73 patients with stand-up electric scooter-related facial injuries, 16 had acute facial osseous fractures. The commonest acute facial osseous fractures were those of the orbit (n=7, 26.9%). Conclusions The patterns of facial trauma reported here can be helpful for quickly evaluating and treating patients with facial trauma related to stand-up electric scooters. Additionally, people riding stand-up electric scooters should be aware of the risks associated with facial trauma and the importance of wearing protective devices, such as helmets and masks.

• Journal of Information Technology Applications and Management
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• v.30 no.5
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• pp.21-40
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• 2023

Scooters are a popular way to get around on your own in many places, such as Taiwan, India, Thailand, etc., because they are easy to move around in, small, and cheaper to buy than cars. On the other hand, traditional scooters that run on fossil fuels put some pollution into the air and add to problems like global warming and air pollution. Switching from scooters that run on fossil fuels to electric scooters can help clean up the air in cities with much pollution. To promote the use of electric scooters, it's important to know how consumers feel about them. The current study investigates consumers' purchase intentions for electric scooters. Based on the questionnaire survey results (n = 567), we found that consumers' environmental concerns, price consciousness, and perceived subjective norms are associated with electric scooter purchase intention. Consumers with price consciousness may choose fossil-fuel-powered scooters because they consider electric-powered scooters more costly, although environmentally friendly. The study gives researchers and practitioners a glimpse into consumers' environmental concerns and subjective norms for a sustainable product.

• Proceedings of the KIPE Conference
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• 2010.07a
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• pp.65-66
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• 2010

This paper deals with PMSM control method for electric scooter. Electric scooter's motor has special structure that is hard to attach resolver or encoder. This paper suggests a method that it is performed of vector control for PMSM using hall sensor. After driving BLDC motor in low speed typically, driving mode is changed to PMSM operation and performs MTPA and flux weakness control. Proposed method is verified through simulation and testing.