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    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Addressing Fire Safety, Ground Impact Resistance, and Thermal Management in Composite EV Battery Enclosures: A Review

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    Lithium-ion batteries are fundamental to modern electric vehicles, offering high energy density, long cycle life, and low self-discharge rates. However, thermal runaway—a critical safety issue involving uncontrolled temperature increases—can lead to fire or explosion. Ensuring flame retardancy is crucial in accidents where battery packs are exposed to external fires. Additionally, battery packs are susceptible to mechanical stresses and potential damage from ground impacts like debris or uneven road surfaces. Effective thermal management significantly impacts capacity and longevity. This review emphasizes the importance of researching flame retardancy, ground impact resistance, and thermal management, especially in composite battery enclosures. Composites serve as a lightweight alternative to metals and help overcome one of the main constraints of EVs, which is weight. Ground impact refers to the physical force battery packs endure during collisions, hitting potholes, debris, or accidents. Therefore, understanding the effects of ground impact on battery enclosures is crucial for design considerations. Effective thermal management is also essential, as it directly affects the performance and safety of Lithium-ion battery packs in EVs

    INVESTIGASI GAYA KONTAK/IMPAK PADA MAIN LANDING GEAR PESAWAT KOMUTER DENGAN PENDEKATAN MULTI-BODY SIMULATION (MBS) RIGID MODELS

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    Landing Gear Drop Test (LGDT) which aims to determine the characteristic of contact/impact force that occurs in the time of the touchdown landing has been conducted. Experimental tests using the apparatus requires a substantial time and cost. Virtual Landing Gear Drop Test (vLGDT) using MSC ADAMS software is one of the solutions for initial stage to testing landing gear. Stiffness values and damping coefficient obtained from vLGDT are 5.0e5 N/m and 1600 N.sec/m. Contact/impact force that occurs on vLGDT is 75996 N, while from experimental is 73612 N. The difference between vLGDT and experimental result is 3.14%.Abstrak:Pengujian landing gear yang bertujuan untuk mengetahui karakteristik gaya kontak/impak yang terjadi saat touchdown landing telah dilakukan. Pengujian eksperimental menggunakan apparatus membutuhkan waktu yang lama dan biaya yang besar. Vitual Landing Gear Drop Test (vLGDT) menggunakan perangkat lunak MSC ADAMS merupakan salah satu alternatif untuk pengujian tahap awal landing gear. Dari simulasi menggunakan vLGDT diperoleh nilai k = 5.0e5 N/m dan cmax = 1600 N.detik/m. Gaya kontak/impak yang terjadi pada simulasi menggunakan vLGDT sebesar 75996 N, sedangkan dari eksperimental sebesar 73612 N. Hasil vLGDT lebih besar 3.14% dibandingkan eksperimental.</jats:p

    Performance Analysis of a Main Drive Motor—Initial Study of an EV Modeling Software Design

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    This study aimed to determine and analyze the performance of an electric motor installed in a small city car, which was an internal combustion engine (ICE) car with manual transmission and front-wheel drive converted into an electric vehicle. A manual transmission vehicle was used, considering its type is the cheapest. This was to push aside the perception that electric cars are not accessible to the lower classes. Another technical matter was the focus on the power and torque performance of the electric motor and the transmission. A 7.5 KW three-phase induction motor was installed and assembled with 200 AH 76.8 VDC batteries. Electronic power steering (EPS) and the air conditioner (AC) were not operated, while power for the electrical accessories and power analyzer was obtained from a separate 12 VDC battery. Vehicle analysis focused on the power consumption, which was measured and acquired using a power analyzer. The vehicle was driven in real terms with three passengers. GPS was also used to determine the vehicle position and collect elevation data during testing. The derivatives of the GPS data were the speed, acceleration, and distance traveled by the vehicle. The initial hypothesis was that the car could cover a distance of 30 km with regular usage

    A investigation of braking system actuators for electric shuttle bus

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    An electric bus is an environmentally friendly mass transportation. Commonly an electric bus uses standard air braking system with pneumatic cylinder for the main actuator. Nevertheless, this will consume the space allocation, greater weight as well as higher energy conversion loss. This study focuses on how to implement an electric braking system for electric bus application in order to overcome the problems above. There are steps to achieve the goal. A preliminary observation is conducted for an electric shuttle bus in Universitas Indonesia to obtain the pattern of braking system during period of journey. This data is then utilized to compare the energy consumption for this application. The result shows that electric actuator for braking system is a potential alternative prime mover for a braking system in a vehicle particularly in an electric bus. Substituting the conventional braking system actuator into the proposed one saves 2030 kWs energy, decreases weight into 90% from its conventional system and cuts 700080 cm3 space in the bus design. Therefore, the optimum component to be selected is the aim for the next work
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