Electric-propulsion systems for ships, also known as electric propulsion devices, represent the current direction of development for maritime power. Issues concerning the environment and fuel economy have compelled the maritime transport sector to seek solutions that reduce emissions and improve fuel efficiency. In this process, power electronics technology plays a significant role in the propulsion systems of ships. Selecting an efficient battery system is of great importance for enhancing the cruising range of yachts and minimizing environmental impact. The battery model is crucial for revealing the working principles of batteries, and it is extremely critical for the application and development of battery technology. The Battery Management System (BMS) serves a crucial regulatory function, optimizing both the safety and performance of battery cells. Central to its operation is the precise estimation of the battery's State of Charge (SOC), a process dependent on an exacting battery model. This system not only enhances longevity and reliability but also ensures that energy storage solutions meet high standards of efficacy. This study focused on testing the impedance characteristics of lithium-sulfur batteries (LSB) at various SOC points and establishing first- and second-order RC equivalent circuit models. The model parameters were identified through experimental data. Subsequently, a simulation platform was constructed using MATLAB/Simulink to simulate the behavior of LSB under a constant current discharge condition. The simulation results showed that the second-order RC model had significantly lower errors than the first-order model, demonstrating higher accuracy. These achievements can provide technical support for the research of energy storage systems in the green aviation and maritime industries.

Despite the presence of the p-Channel MOSFET inrush current limiter circuit within the power supply unit of military radar, The internal MOSFET and DC-DC Converter has been damaged due to the high inrush current. In this paper, the cause of the high inrush current was identified by analyzing the p-Channel MOSFET inrush current limiter circuit. Based on the analysis, the high inrush current was reduced by about 60% by adjusting the time constant of the source-to-gate elements compared to before improvement.

In this study, the safety aspects were studied by comparing the charge control characteristics of the two vehicles when a failure occurs between the OBC including the charging port or the charging door module (CDM) during slow charging using the In Cable Control Box (ICCB) for a long time.When the AC terminal was momentarily disconnected during charging, the Model-3 vehicle was charged normally if the AC circuit was disconnected up to three times, and the charging control was stopped when the number of disconnects reached four times. However, in the Ioniq-5 vehicle, charging control was normally performed when the disconnected AC circuit was normally connected regardless of the number of disconnection.

Devices with negative differential transconductance (NDT) and negative differential resistance (NDR) have shown a strong potential for digital electronics with high information density due to their N-shaped current–voltage (I–V) characteristics leading to multiple threshold voltages ( Vths). The 2D materials, such as graphene, hBN, MoS2, WS2, etc., offer an attractive platform to achieve NDT and NDR because of the absence of dangling bonds on the surface, leading to a high-quality interface between the layers. The 2D materials' unique property of the weak van der Waals (vdW) interactions without dangling bonds on the heterostructure devices shows the way for the applications more than-Moore devices. This review holds a well-timed overview of 2D materials-based devices to develop future multi-valued logic (MVL) circuits exhibiting high information density. Notably, the recent advances in emerging 2D materials are reviewed to support the directions for future research on MVL applications.

In the wire constituting the LIN, which is one of the vehicle communication devices, disconnection of the wire or contact resistance of the circuit occurs due to vibration and aging of the vehicle. This affects the entire communication network and may have a significant impact on the safe driving of the vehicle as information is not transmitted. In this study, a LIN BUS circuit simulator was built on its own like a real car and measured with an automotive oscilloscope instead of a common method of measuring and diagnosing a circuit with a multimeter in the event of a LIN BUS circuit failure. Referring to the experimental results, it will be possible to diagnose faults in circuits efficiently and quickly.

This study analyzes the effects of the number of angles and bends on resistance in a conductor-embroidered stitch circuit for efficient power transfer through a conductor of wearable energy harvesting to study changes in power lost through connection with actual solar panels. In this study, the angle of the conductive stitch circuit was designed in units of 30°, from 30° to 180°, and the resistance was measured using an analog Discovery 2 device. The measured resistance value was analyzed, and in the section of the angle where the resistance value rapidly changes, it was measured again and analyzed in units of 5°. Following this, from the results of the analysis, the angle at which the tension was applied to the stitch converges was analyzed, and the resistance was measured again by varying the number of bends of the stitch at the given angle. The resistance decreases as the angle of the stitch decreases and the number of bends increases, and the conductor embroidery stitch can reduce the loss of power by 1.61 times relative to general embroidery. These results suggest that the stitching of embroidery has a significant effect on the power transfer in the transmission through the conductors of wearable energy harvesting. These results indicate the need for a follow-up study to develop a conductor circuit design technology that compares and analyzes various types of stitches, such as curved stitches, and the number of conductors, so that wearable energy harvesting can be more efficiently produced and stored.

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.

When the CP voltage is disconnected, the measured voltage on the ICCB side is measured to be 12V, and the voltage on the OBC side is measured to be 0V. When the PD signal was disconnected, the ICCB-side measured voltage was 0V and the OBC-side measured voltage was 4.5V. From this, disconnected position be found with the voltage value measured. When CP was disconnected for a short time, the PD voltage did not change to 1.5V, and when the PD was disconnected, the CP signal and PD signal changed to 9V, and if the CP and PD voltages were normal, the charge control could be performed normally.

Background: The circuit exercise program is a continuous method that combines complex training types and is an exercise method that is performed to improve performance by improving basic physical strength such as strength, agility, endurance and muscular endurance. Objectives: To examine the effect of exercise program on pulmonary function of professional volleyball players. Design: Randomized controlled trial. Methods: 22 professional volleyball players were divided into two groups of 11 each. A high intensity interval exercise program and circuit exercise program were performed twice a week for 45 minutes for 4 weeks. Results: The changes in pulmonary function in professional volleyball players were significantly different pre and post the intervention in both groups and the interval exercise program group showed a more significant difference before and after the intervention in Forced Expiratory Volume in 1 Second (FEV1) and Forced Expiratory Volume in 1 Second/Forced Vital Capacity (FEV1/FVC) (P<.05). In addition, there was also a significant difference in FEV1 and FEV1/FVC between two groups (P<.05). Conclusion: The interval exercise program group was effective in improving pulmonary function for professional volleyball players.

The electrochemical reaction between lead borate glass frit doped with Sn metal filler and Ni-Cr wire of a J-type resistor during a term of Joule heating is investigated. The fusing behavior in which the Ni-Cr wire is melted is not observed for the control group but measured for the Sn-doped specimen under 30 V and 500 mA. The Sn-doped lead borate glass frit shows a fusing property compared with other metal-doped specimens. Meanwhile, the redox reaction significantly contributes to the fusing behavior due to the release of free electrons of the metal toward the glass. The electrons derived from the glass, which used Joule heat to reach the melting point of Ni-Cr wire, increase with increasing corrosion rate at interface of metal/ glass. Finally, the confidence interval is 95 ± 1.959 %, and the adjusted regression coefficient, R in the optimal linear graph, is 0.93, reflecting 93% of the data and providing great potential for fusible resistor applications.

In this paper, each controller's unique ID and PICO oscilloscope were used to measure the voltage waveform of each CAN communication line, and compare and analyze the serial decoding results. Using the voltage change level of the CAN communication line, it was possible to check whether the CAN-High line and the Low line were disconnected. And it was possible to infer the circuit disconnection point between the controller and the controller only with the unique ID information of each controller. And when the CAN-High circuit was disconnected, the voltage of the high line was measured at the same voltage level as the Low line.

In this study, quantum dot-sensitized solar cells (QDSSC) using CdSe/ZnS quantum dots (QD) of various sizes with green, yellow, and red colors are developed. Quantum dots, depending their different sizes, have advantages of absorbing light of various wavelengths. This absorption of light of various wavelengths increases the photocurrent production of solar cells. The absorption and emission peaks and excellent photochemical properties of the synthesized quantum dots are confirmed through UV-visible and photoluminescence (PL) analysis. In TEM analysis, the average sizes of individual green, yellow, and red quantum dots are shown to be 5 nm, 6 nm, and 8 nm. The J-V curves of QDSSC for one type of QD show a current density of 1.7 mA/cm2 and an open-circuit voltage of 0.49 V, while QDSSC using three type of QDs shows improved electrical characteristics of 5.52 mA/cm2 and 0.52 V. As a result, the photoelectric conversion efficiency of QDSSC using one type of QD is as low as 0.53 %, but QDSSC using three type of QDs has a measured efficiency of 1.4 %.

In this paper, we analyze various types of racing lines and search for the optimum time to pass through the chicane, which are corners smaller than 90 degree. “Best” means the minimum time at maximum speed. This indicates that the inside and outside of the running line is not able to never win the internal between the connected lines. Even in the case of Chicane driving, the vehicle can accelerate at a high speed by increasing the turning radius near the straight line. In the study, the turning angle is inevitable if the angle is large because the turning angle is 44.3 because there is no straight running width. Therefore, by keeping the speed close to the straight line along the path of the incinerator, the speed of escape from the line can be shortened.

With the development of industrial technology and science, production and manufacturing facilities have been enhanced and improved, and the importance of the safety of workers has also been regulated and limited by various safety management methods. As a way to secure the safety of the workers from the production facility, the fail-safe and fool-proof methods are now being applied. Any possible insecure behavior and unsafe conditions can be removed by adopting the standards and specifications that are now secure the safety of workers and equipment. This research analyzes EN ISO 13849-1 international and European standards during CE certification. In order to secure acceptable reduced risks, the risk assessment process of ISO 12100 and the processes for reducing its risk are applied. In the current ISO 13849-1 standard, the criteria for the required performance level PLr (Required Performance Level) for the applicable risk and safety functions through the risk assessment are subjective and not subdivided. Therefore, the evaluation criteria are likely to cause judge’s judgement error due to qualitative judgement. This research focuses on evaluation and acceptable performance level setting for the safety circuit of the equipment. We propose an objective and specific evaluation criteria to secure safety, and the proposed evaluation criteria are applied to the case study of the safety circuit for the equipment. In order to secure the safety of the entire safety circuit, the improvement of the MTTFd and DC level related to the SRP/CS (Safety-Related Parts of Control Systems)’ lifetime is required for the future research.

역전기투석전지는 염수-기수의 농도차이를 원동력으로 이온교환막의 선택성에 의해 양이온과 음이온을 서로 반대방향으로 이동시켜 전력을 생산한다. 이상적인 이온교환막의 경우 35 g/L과 0.5 g/L 농도의 염수와 기수를 흘려 보냈을 때, 약 0.1 V의 전압 출력을 가진다. 본 연구에서는 역전기투석 스택전지의 출력특성에 영향을 주는 인자로서 막저항, 염수와 기수의 전기전도도, 막 이동수, 막 면적, 유로 두께 및 메쉬의 개방면적비, 스택수 등을 고려하여 수치모사를 수행하였다. 스택전지 내 유로에서 발생하는 누설전류 및 내부저항을 고려한 등 가회로모델을 수립하였고, 상용 이온교환막으로 제작된 스택전지 실험결과로부터 개방전압, 단락전류밀도, 최대전력밀도와 같은 중요 전지특성에 대하여 수치 모사의 정합성을 확인하였다.

In commercial solar cells, the pattern of the front electrode is critical to effectively assemble the photo generated current. The power loss in solar cells caused by the front electrode was categorized as four types. First, losses due to the metallic resistance of the electrode. Second, losses due to the contact resistance of the electrode and emitter. Third, losses due to the emitter resistance when current flows through the emitter. Fourth, losses due to the shading effect of the front metal electrode, which has a high reflectance. In this paper, optimizing the number of finger on a 4 ´ 4 solar cell is demonstrated with known theory. We compared the short circuit current density and fill factor to evaluate the power loss from the front metal contact calculation result. By experiment, the short circuit current density(Jsc), taken in each pattern as 37.61, 37.53, and 37.38 mA/ cm2 decreased as the number of fingers increased. The fill factor(FF), measured in each pattern as 0.7745, 0.7782 and 0.7843 increased as number of fingers increased. The results suggested that the efficiency(Eff) was measured in each pattern as 17.51, 17.81, and 17.84 %. Throughout this study, the short-circuit current densities(Jsc) and fill factor(FF) varied according to the number of fingers in the front metal pattern. The effects on the efficiency of the two factors were also investigated.

Animals must maintain proper balance between energy intake and expenditure. Recently, we descovered the enzymaticco-factor tetrahydrobiopterin (BH4) inhibits feeding in Drosophila. BH4 biosynthesis requires the sequential action of theconserved enzymes Punch, Purple, and Sepiapterin Reductase (Sptr). Although we observe increased feeding upon lossof Punch and Purple in the adult fat body, loss of Sptr must occur in the brain. We found Sptr expression is requiredin four adult brain neurons that express NPF, the fly homologue of the vertebrate appetite regulator NPY. Mechanistically,we found BH4 deficiency reduces NPF levels, while excess BH4 increases NPF accumulation without altering its expression.