http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Di Han,Bulent Sarlioglu 전력전자학회 2015 JOURNAL OF POWER ELECTRONICS Vol.15 No.6
Gallium nitride (GaN)-based power switching devices, such as high-electron-mobility transistors (HEMT), provide significant performance improvements in terms of faster switching speed, zero reverse recovery, and lower on-state resistance compared with conventional silicon (Si) metal–oxide–semiconductor field-effect transistors (MOSFET). These benefits of GaN HEMTs further lead to low loss, high switching frequency, and high power density converters. Through simulation and experimentation, this research thoroughly contributes to the understanding of performance characterization including the efficiency, loss distribution, and thermal behavior of a 160-W GaN-based synchronous boost converter under various output voltage, load current, and switching frequency operations, as compared with the state-of-the-art Si technology. Original suggestions on design considerations to optimize the GaN converter performance are also provided.
A NEW MEAN VALUE RELATED TO D. H. LEHMER'S PROBLEM AND KLOOSTERMAN SUMS
Han, Di,Zhang, Wenpeng Korean Mathematical Society 2015 대한수학회보 Vol.52 No.1
Let q > 1 be an odd integer and c be a fixed integer with (c, q) = 1. For each integer a with $1{\leq}a{\leq}q-1$, it is clear that the exists one and only one b with $0{\leq}b{\leq}q-1$ such that $ab{\equiv}c$ (mod q). Let N(c, q) denote the number of all solutions of the congruence equation $ab{\equiv}c$ (mod q) for $1{\leq}a$, $b{\leq}q-1$ in which a and $\bar{b}$ are of opposite parity, where $\bar{b}$ is defined by the congruence equation $b\bar{b}{\equiv}1$ (modq). The main purpose of this paper is using the mean value theorem of Dirichlet L-functions to study the mean value properties of a summation involving $(N(c,q)-\frac{1}{2}{\phi}(q))$ and Kloosterman sums, and give a sharper asymptotic formula for it.
Han, Di,Sarlioglu, Bulent The Korean Institute of Power Electronics 2015 JOURNAL OF POWER ELECTRONICS Vol.15 No.6
Gallium nitride (GaN)-based power switching devices, such as high-electron-mobility transistors (HEMT), provide significant performance improvements in terms of faster switching speed, zero reverse recovery, and lower on-state resistance compared with conventional silicon (Si) metal-oxide-semiconductor field-effect transistors (MOSFET). These benefits of GaN HEMTs further lead to low loss, high switching frequency, and high power density converters. Through simulation and experimentation, this research thoroughly contributes to the understanding of performance characterization including the efficiency, loss distribution, and thermal behavior of a 160-W GaN-based synchronous boost converter under various output voltage, load current, and switching frequency operations, as compared with the state-of-the-art Si technology. Original suggestions on design considerations to optimize the GaN converter performance are also provided.
A new mean value related to D. H. Lehmer's problem and Kloosterman sums
Di Han,Wenpeng Zhang 대한수학회 2015 대한수학회보 Vol.52 No.1
Let $q>1$ be an odd integer and $c$ be a fixed integer with $(c, q)=1$. For each integer $a$ with $1\le a \leq q-1$, it is clear that there exists one and only one $b$ with $0\leq b \leq q-1$ such that $ab \equiv c $ (mod $q$). Let $N(c, q)$ denote the number of all solutions of the congruence equation $ab \equiv c$ (mod $q$) for $1 \le a, b \leq q-1$ in which $a$ and $\overline{b}$ are of opposite parity, where $\overline{b}$ is defined by the congruence equation $b\overline{b}\equiv 1$ $(\bmod q)$. The main purpose of this paper is using the mean value theorem of Dirichlet $L$-functions to study the mean value properties of a summation involving $\left(N(c, q)-\frac{1}{2}\phi(q)\right)$ and Kloosterman sums, and give a sharper asymptotic formula for it.
Experimental analysis of SO<sub>2</sub> effects on Molten Carbonate Fuel Cells
Di Giulio, N.,Bosio, B.,Han, J.,McPhail, S.J. Pergamon Press ; Elsevier Science Ltd 2014 International journal of hydrogen energy Vol.39 No.23
The aim of this work is to investigate how SO<SUB>2</SUB> can affect MCFC performance and to discover the possible mechanisms involved in cathode sulphur poisoning, specifically considering the possible use of MCFCs in CCS (Carbon Capture and Storage) application. The different contributions of cathodic, anodic and electrolyte reactions have been considered to get a complete picture of the evolution of performance degradation. Experimental tests have been performed at the Fuel Cell Centre laboratories of Korea Institute of Science and Technology (KIST) thanks to 100 cm<SUP>2</SUP> single cell facilities and comparing results using both an optimized gas for laboratory conditions and a gas composition that simulates MCFCs when running in a Natural Gas Combined Cycle (NGCC) power plant. Polarisation curves, endurance tests, impedance measurements and gas analyses have been carried out to support the investigation.
A Seamless Constraint Model of Multi-Scale Representation of Geographical Information
Di Chen,Han Yue,Xinyan Zhu 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.8
At present, it has become a hot issue to provide a multi-representation mechanism and build multi-scale spatial databases in the field of GIS. Meanwhile, an inevitable problem is how to evaluate and preserve the consistency of multi-scale spatial data. In this paper, we introduce the concepts of homonymous points and homonymous entities based on innate characteristics of spatial data and put forward a seamless constraint model of multi-scale representation of geographic information that involves time, geometry, spatial relations and semantic characteristics. According to this model, a consistency assessment method has been implemented by computing similarities between vector data at three different scales. The main contributions of this paper are the proposal of a consistency constraint model and assessment system of multi-scale spatial data.