The The purpose of this study is to establish evaluation criteria for the purchase of electric vehicles and to present an evaluation model using quantitative scales for evaluation factors. This study was limited to the study of purchasing factors related to electric vehicles, and the spatial scope was limited to potential buyers in their 20s to 50s living in the Daejeon area. Based on the survey, the factors affecting the purchase factors (energy economics, image, performance, maintenance, price) were examined using the AHP method, and the priorities were analyzed to determine how much influence these factors have on the purchase of electric vehicles. In addition, in order to verify the logical consistency of the survey items, a consistency ratio test (c) was conducted. Through this study, priority considerations for the purchase of electric vehicles were presented, and information on future consumer interest in electric vehicles was conducted. It is judged to be able to provide an opportunity to provide various services for each layer.

The Alkali-Metal Thermal to Electric Converter (AMTEC) can be used as a next-generation power generation technology related with a large thermal energy storage. In particular, this technology is expected for the higher efficiency by a cascade power generation with the thermoelectric generator(TEG), and the temperature distribution becomes a very important design parameter in this case. In this study, the temperature distribution of the AMTEC unit was analyzed through CFD analysis, and design points were discussed based on the results.

In this study, two ventilation holes were considered to prevent condensation in the circular column supporting the provision crane on a training ship(Saenuri) for Mokpo National Maritime University. The ventilation holes could be understood as the most simple and inexpensive way to prevent condensation because it was formed only by drilling. If sufficient ventilation is provided, the insulation and corrosion of an electric motor can be improved, and a comfortable state can be ensured in the circular column. The circular column had an electric motor for driving the provision crane so that the basic principle was to utilize the kinetic energy for the flow field from a cooling fan in the circular column. The ventilation holes attenuated the low-velocity area in the circular column and contributed to internal flow circulation with updrafts. The results were discussed through numerical analysis based on computational fluid dynamics.

In this paper, a simulation computerized crash analysis evaluation method through reverse engineering was applied to the Defender vehicle to systemize and simplify the certification of small-scale electric vehicles. The Defender vehicle was selected as a benchmarking vehicle that converts into an electric vehicle, and the layout of the frame and element analysis of individual parts were conducted through reverse engineering. To review the vehicle package layout, the fastening and assembly method for each part was analyzed referring to the Defender maintenance guide and parts list, and it was used for frame element technology analysis. In addition, collisions according to the main frame material and the shape of the crash box were analyzed, and various cases were analyzed through parameter study. As a result of the crash analysis, it was found that the mild steel main frame could not guarantee the safety of the vehicle in a fixed wall collision situation, and the ATOS material would increase the collision safety of the Defender relatively. Through the crash analysis according to the shape of the crash box, it was found that the strength of the crash box is too high compared to the main body, and this should be reflected in the design for small-volume production of multiple products.

With the continuous prosperity and development of the marine industry, the number of ships is increasing while greenhouse gas emissions are rising. In order to meet the relevant international ship emission regulations, the solution of developing electric ships is proposed. As the core device of the electric ship propulsion system, the maturity and applicability of power battery technology play a key role in the development of the electric ship. This article introduces the principles and advantages of the fuel cell, lithium-ion battery as well as supercapacitor battery, respectively, and analyzes the application status and challenges of power batteries in existing electric ships. The development direction and problems to be solved of power battery in current and future ship applications are put forward, which can provide a reference for further research.

EPS(Electric Power Steeing) has been a popular system in the automotive industry since 2000 after the technology and safety was validated. The Korean Refrigerated Carts like Hankook Yogurt Coco was developed for the first time in the world. However this carts system and other small tranporting carts has no EPS. Thus the drivers of carts needed a EPS to avoid the burden when steeing a big weighted cart with 750Kgf as many women drivers complain the pain on their shoulders. This paper describes the application of EPS on Korean refrigerated carts with simulation results and experimental data shows the improvement of steering efforts.

In Korea, five major ports have been designated as sulfur oxide emission control areas to reduce air pollutant emissions, in accordance with Article 10 of the “Special Act on Port Air Quality” and Article 32 of the “Ship Pollution Prevention Regulations”. As regulations against vesseloriginated air pollutants (such as PM, CO2, NOx, and SOx) have been strengthened, the Ministry of Oceans and Fisheries(MOF) enacted rules that newly built public ships should adopt eco-friendly propulsion systems. However, particularly in diesel–electric hybrid propulsion systems,the demand for precise control schemes continues to grow as the fuel saving rate significantly varies depending on the control strategy applied. The conventional Power Take In–Power Take Off(PTI–PTO) mode control adopts a rule-based strategy, but this strategy is applied only in the low-load range and PTI mode; thus, an additional method is required to determine the optimal fuel consumption point. The proposed control method is designed to optimize fuel consumption by applying the equivalent consumption minimization strategy(ECMS) to the PTI–PTO mode by considering the characteristics of the specific fuel oil consumption(SFOC) of the engine in a diesel–electric hybrid propulsion system. To apply this method, a specific fishing vessel model operating on the Korean coast was selected to simulate the load operation environment of the ship. In this study, a 10.2% reduction was achieved in the MATLAB/SimDrive and SimElectric simulation by comparing the fuel consumption and CO2 emissions of the ship to which the conventional rule-based strategy was applied and that to which the ECMS was applied.

In this study, N/S co-doped carbon felt (N/S-CF) was prepared and characterized as an electrode material for electric double-layer capacitors (EDLCs). A commercial carbon felt (CF) was immersed in an aqueous solution of thiourea and then thermally treated at 800 oC under an inert atmosphere. The prepared N/S-CF showed a large specific surface area with hierarchical pore structures. The electrochemical performance of the N/S-CF-based electrode was evaluated using both 3- electrode and 2-electrode systems. In the 3-electrode system, the N/S-CF-based electrode showed a good specific capacitance of 177 F/g at 1 A/g and a good rate capability of 41% at 20 A/g. In the 2-electrode system (symmetric capacitor), the freestanding N/S-CF-based electrode showed a specific capacitance of 275 mF/cm2 at 2 mA/cm2, a rate capability of 62.5 % at 100 mA/cm2, a specific power density of ~ 25,000 mW/cm2 at an energy density of 23.9 mWh/cm2, and a cycling stability of ~ 100 % at 100 mA/cm2 after 20,000 cycles. These results indicate the N/S co-doped carbon felts can be a promising candidate as a new electrode material in a symmetric capacitor.

This research studied faults that may occur during slow charging using the J1772 adapter of Tesla Model-3 electric vehicles. When the AC terminal was instantaneously disconnected, charging was performed normally when an AC circuit with disconnection up to three disconnection times was connected. Charging control was suspended when the number of disconnection reached four times. However, if the AC disconnection time exceeded 22 seconds, the charging control was stopped regardless of the number of disconnection. When a contact failure occurred at the AC terminal, high surge current and noise occurred. However, when the contact improved, the charging control continued. In terms of safety, it seems necessary to take measures such as stopping charging control when detecting noise.

대부분의 기계는 여러 종류의 금속으로 구성된다. 특히 선박의 축계는 프로펠러 날개의 황동과 스테인리스로 된 축으로 이루 어져 있다. 이 이종금속이 바닷물의 전해액에 들어가면 볼타 전지를 이루고, 기전력이 발생된다. 이 기전력은 축계를 받치고 있는 베어링 과 축을 전기부식 시키는 원인이 된다. 선박에서는 이 부식을 막기 위해 선박에서는 축 접지 시스템을 설치하여 운용하고 있다. 본 연구 는 가변피치 프로펠러의 축기전력을 측정하기 위하여 추진축의 전압과 주기관의 회전수를 동시에 측정하였다. 측정장치는 내셔널인스트 루먼트사의 24bit A/D컨버터를 사용하여 측정하였고, 프로그램은 LabVIEW를 사용하였다. 주기관의 회전수와 축기전력의 발생, 블레이드 각도에 따른 기전력과, 배의 항해 방향에 따른 축기전력을 측정하고 분석하였다.