Jin-Beom Chung

The performance of a plug-in hybrid electric vehicle (PHEV) or an electric vehicle (EV) is closely related to the performance of its high-voltage battery pack. This is why, among the various means of maintaining a battery's peak performance, the importance of thermal management is emphasized. Since the early stages of the development of Li-ion batteries, much emphasis has been placed on battery cooling in order to secure stability, while less attention has been given to battery heating. However,

With the recent interest in environment-friendly vehicles such as electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs), various topologies are being proposed for the on-board charger (OBC) required to charge the lithium battery that serves as the energy storage system. If a specific topology is selected and used, the output current of the charger is bound to contain low-frequency ripple that is twice the input power supply frequency. In this study, to analyze the effects of the l

In this study, a 1.5 [kW] on-board battery charger for neighborhood electric vehicles was developed. The developed charger has a built-in power factor correction circuit and a resonant phase shift full-bridge (PSFB) for power conversion. Although an additional snubber is not used, the switching noise generated in the switch and the diode is reduced, owing to the built-in resonant-type PSFB converter, and the desired improvement in noise reduction and efficiency of input/output is achieved. The p

Acute hepatitis A (AHA) is one of the most common infectious diseases; it is usually a self-limiting disease affecting the liver. Although extrahepatic manifestations are not common, some cases have been reported associated with acute renal failure. We reviewed the clinical features of patients with AHA complicated by acute renal failure (ARF group) and compared them with patients with noncomplicated AHA (non-ARF group). The medical records of 208 consecutive patients with AHA who were diagnosed

Owing to high oil prices and the efforts to reduce greenhouse gases according to the United Nations Framework Convention on Climate Change, there has been active research and development on environmentally friendly, high‐efficiency vehicles. In developing the system design and specifications of an environmentally friendly vehicle, various simulations have been performed on the different components and the overall system. Although a precise modelling of each part and the system as a whole is nece

Online simulations are utilized to reduce time and cost in the development and performance optimization of plug-in hybrid electric vehicle (PHEV) and electric vehicles (EV) systems. One of the most important factors in an online simulation is the accuracy of the model. In particular, a model of a battery should accurately reflect the properties of an actual battery. However, precise dynamic modeling of high-capacity battery systems, which significantly affects the performance of a PHEV, is diffi

The ultracapacitor module has recently been recast for use in hybrid energy storage systems (HESSs). As a result, accurate state-of-charge (SOC) estimation for an ultracapacitor module is as important as that of primary sources in order to be utilized efficiently in an energy storage system (ESS). However, while SOC estimation via the open-circuit voltage (OCV) method is generally used due to its linear characteristics compared with other ESSs, this method results in many errors in cases of high

The purpose of this study was to compare the performance of different commercial quality assurance (QA) systems for the pretreatment verification plan of stereotactic body radiotherapy (SBRT) with volumetric arc therapy (VMAT) technique using a flattening-filter-free beam. The verification for 20 pretreatment cancer patients (seven lung, six spine, and seven prostate cancers) were tested using three QA systems (EBT3 film, I’mRT MatriXX array, and MapCHECK). All the SBRT-VMAT plans were optimized

To improve the cycle life and efficiency of an energy storage system for HEV, a dynamic control system consisted of a switch between battery and ultracapacitor module and a controller is proposed, which is appropriate for mild hybrid vehicle with 42 V power net. The switch can be controlled based on the status of the battery and the ultracapacitor module, and a control algorithm that could largely decrease the number of high charging current peak is also implemented. Therefore the cycle life of

이 논문은 아도르노 철학의 핵심 문제 중 하나인 정신과 자연의 화해가능성을 해명하기 위하여 정신을 동일성 및 친화성 원칙 속에서 규정한다. 이를 위한 근거가 되는 것은 정신의 자연사적 기원에 관한 아도르노의 두 가지테제(“정신은 자기보존에서 발생했다”와 “미메시스는 정신의 생리학적 전형식이다”)이며, 이에 따라 정신은 각각 동일성 그리고 친화성 원칙 속에서 파악될수 있다. 상세한 고찰 속에서 밝혀질 바는 이 개념들의 양의성 및 상호지시성이다. 아도르노에게 있어 동일성은 자기보존 및 자연지배의 수단이지만 동시에화해적 잠재력의 담지자라는 이중의 사실을 의미한다. 그러나 동일성의 틀 안에 갇혀 있는 한 정신은 자신과 타자의 근원적 관계를 충분히 자각할 수 없다는 한계에 노출된다. 마찬가지로 친화성 개념 또한 이중적인데, 한편으로 그것은 합리성의 타자로서 퇴행을 의미하지만 다른 한편 동일성 정신을 질적으로변화시킴으로써 그것을 타락에서 구제해줄 해방의 계기이기 때문이다. 그러나친화성, 미메시

Hybrid electric vehicles (HEV) utilize electric power as well as a mechanical engine for propulsion; therefore the performance of HEVs can be directly influenced by the characteristics of the energy storage system (ESS). The ESS for HEVs generally requires high power performance, long cycle life and reliability, as well as cost effectiveness, so the hybrid energy storage system (HESS), which combines different kinds of storage devices, has been considered to fulfill both performance and cost req

The purpose of this research were to verify the accuracy of dose calculation by using the analytical anisotropic algorithm (AAA) and Acuros XB (AXB) against measurements within an air cavity for small fields from a 6-MV flattening filter-free (FFF) beam. A rectangular slab phantom containing an air cavity was specially constructed for this study. Computed tomography (CT) image data sets were acquired with and without a film at four selected depths (4.5, 5.5, 6.5, and 7.5 cm) in the air cavity of

Since the impedance of a battery is an important variant that can be used to estimate the state of the battery, such as the state of charge, current life expectancy, and remaining capacity, an accurate measurement of impedance is required, and the significance of impedance measurement becomes more pronounced when it comes to high-voltage battery packs, which are composed of numerous cells. However, previous studies have been developed focusing only on cells or low-voltage packs, making it diffic