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[en] Light reflected or transmitted by a planetary atmosphere contains information about particles and molecules in the atmosphere. Therefore, accurate modeling of the radiation field may be used to retrieve information on atmospheric composition. In this paper, a multi-layer model for a vertically inhomogeneous atmosphere is implemented by using the doubling-adding method for a plane-parallel atmosphere. By studying the degree of linear polarization of the transmitted and reflected solar light in the Huggins bands, we find significant differences between tropospheric ozone and stratospheric ozone. The effects of tropospheric ozone change on the linear polarization are 10 times more than that of the same amount of stratospheric ozone change. We also show the aerosol effect on the linear polarization, but this effect is wavelength independent as compared to that caused by the tropospheric ozone change. The results provide a theoretical basis for the retrieval of tropospheric ozone from measurement of linear polarization of the scattered sunlight both from the ground and from a satellite
[en] The polysilicon p-i-n diode displays noticeable process compatibility and portability in advanced technologies as an electrostatic-discharge (ESD) protection device. This paper presents the reverse breakdown, current leakage and capacitance characteristics of fabricated polysilicon p-i-n diodes. To evaluate the ESD robustness, the forward and reverse TLP I–V characteristics were measured. The polysilicon p-i-n diode string was also investigated to further reduce capacitance and fulfill the requirements of tunable cut-in or reverse breakdown voltage. Finally, to explain the effects of the device parameters, we analyze and discuss the inherent properties of polysilicon p-i-n diodes. (semiconductor devices)
[en] This paper presents an improved analytical model for an RF-LDMOST structure based on the 2D Poisson equation. The derived model indicates the influence of high doped shallow drift and low doping concentration p epitaxial layer on the electric field distribution. In particular, the importance of the thickness of the p epitaxial layer for electric field distributions in RF-LDMOST are shown through MATLAB analytical results based on the model. Then ISE TCAD simulations and experiments are processed and their results are in agreement with the analytical model. This model contributes to the comprehension and optimization design of RF-LDMOST. (semiconductor devices)
[en] This paper presents the investigation of integrated electro-static discharge (ESD) protection design for the gate oxide of an RF-LDMOS (radio frequency lateral double diffusion MOS). Through a comprehensive discussion of experimental and simulated results, a cascoded NMOS is presented as appropriate integrated gate oxide ESD protection with a high holding voltage and a flexible ESD design window. (semiconductor devices)
[en] The impedance and output power measurements of LDMOS transistors are always a problem due to their low impedance and lead widths. An improved thru-reflect-line (TRL) calibration algorithm for measuring the characteristics of L-band high power LDMOS transistors is presented. According to the TRL algorithm, the individual two-port S parameters of each fixture half can be obtained. By de-embedding these S parameters of the test fixture, an accurate calibration can be made. The improved TRL calibration algorithm is successfully utilized to measure the characteristics of an L-band LDMOS transistor with a 90 mm gate width. The impedance of the transistor is obtained, and output power at 1 dB compression point can reach as much as 109.4 W at 1.2 GHz, achieving 1.2 W/mm power density. From the results, it is seen that the presented TRL calibration algorithm works well. (semiconductor devices)
[en] Highlights: • Improving the utilization of wind power by the demand response of residential hybrid energy system. • An optimal scheduling of home energy management system integrating micro-CHP. • The scattered response capability of consumers is aggregated by demand bidding curve. • A stochastic day-ahead economic dispatch model considering demand response and wind power. - Abstract: As the installed capacity of wind power is growing, the stochastic variability of wind power leads to the mismatch of demand and generated power. Employing the regulating capability of demand to improve the utilization of wind power has become a new research direction. Meanwhile, the micro combined heat and power (micro-CHP) allows residential consumers to choose whether generating electricity by themselves or purchasing from the utility company, which forms a residential hybrid energy system. However, the impact of the demand response with hybrid energy system contained micro-CHP on the large-scale wind power utilization has not been analyzed quantitatively. This paper proposes an operation optimization model of the residential hybrid energy system based on price response, integrating micro-CHP and smart appliances intelligently. Moreover, a novel load aggregation method is adopted to centralize scattered response capability of residential load. At the power grid level, a day-ahead stochastic economic dispatch model considering demand response and wind power is constructed. Furthermore, simulation is conducted respectively on the modified 6-bus system and IEEE 118-bus system. The results show that with the method proposed, the wind power curtailment of the system decreases by 78% in 6-bus system. In the meantime, the energy costs of residential consumers and the operating costs of the power system reduced by 10.7% and 11.7% in 118-bus system, respectively.
[en] This paper presents a new phenomenon, where the holding-voltage of a silicon-controlled rectifier acts as an electrostatic-discharge protection drift in diverse film thicknesses in silicon-on-insulator (SOI) technology. The phenomenon was demonstrated through fabricated chips in 0.18 μm SOI technology. The drift of the holding voltage was then simulated, and its mechanism is discussed comprehensively through ISE TCAD simulations. (semiconductor devices)
[en] Highlights: • The transfer of power fluctuation in the integrated energy system with intermittent renewable energy sources is considered. • Nonlinear multi energy coupling characteristics modeling of combined cooling heating and power system (CCHP). • A dynamic coordinated optimization model considering electricity-gas distribution network and multi-CCHP system. • A two-stage optimization algorithm for solving the mixed-integer nonlinear programming problem. - Abstract: As the increasing penetration of renewable energy sources in distribution network, the tie-line power fluctuation caused by intermittent renewable energy produces a detrimental impact on security and reliability of the main grid. Therefore, maximization of renewable energy utilization as well as stabilization of tie-line power fluctuation are both required in the distribution network, to ease the power regulation burden of main grid. Remarkably, the development of integrated energy systems makes it possible to transfer the fluctuation in power network to other larger inertial systems. This paper proposes a coordinated operation strategy for the gas-electricity integrated distribution system, considering AC power flow in the power network and the gas hydraulic calculation in gas network. In addition, based on the nonlinear multi-energy coupling external characteristics modeling of CCHP system, the power fluctuation of renewable energy sources is transferred to gas distribution network and cooling or heating system by coordinated operation of Multi-CCHPs. Moreover, a two-stage optimization algorithm is proposed to solve the corresponding mixed integer nonlinear programming (MINLP) problem. The simulations conducted on 33-node power distribution network and 24-node gas network show that the proposed method can effectively smooth the tie-line power fluctuation in variety case.
[en] Sensitivity studies have been performed to evaluate the errors resulting from ignoring polarization in analyzing spectroscopic measurements of the O2 A band from space, using the Orbiting Carbon Observatory (OCO) as a test case. An 11-layer atmosphere, with both gas and aerosol loading, and bounded from below by a lambertian reflecting surface, was used for the study. The numerical computations were performed with a plane-parallel vectorized discrete ordinate radiative transfer code. Beam and viewing geometry, surface reflectance and aerosol loading were varied one at a time to evaluate and understand the individual errors. Different behavior was observed in the line cores and the continuum because of the different paths taken by the photons in the two cases. The errors were largest when the solar zenith angle was high, and the aerosol loading and surface reflectance low. To understand the effect of neglecting polarization on CO2 column retrievals, a linear error analysis study was performed on simulated measurements from the OCO spectral regions, viz. the 1.61 and 2.06 μm CO2 bands and the O2 A band. It was seen that neglecting polarization could introduce errors as high as 10 ppm, which is substantially larger than the required retrieval precision of ∼2 ppm. A variety of approaches, including orders of scattering, spectral binning and the use of lookup tables are being explored to reduce the errors
[en] Purpose. To compare a necrosis-avid contrast agent (NACA) bis-Gd-DTPA-pamoic acid derivative (ECIII-60) after intracoronary delivery with an extracellular agent Gd-DTPA after intravenous injection on magnetic resonance imaging (MRI) in a swine model of acute reperfused myocardial infarction (MI). Methods. Eight pigs underwent 90 min of transcatheter coronary balloon occlusion and 60 min of reperfusion. After intravenous injection of Gd-DTPA at a dose of 0.2 mmol/kg, all pigs were scanned with T1-weighted MRI until the delayed enhancement of MI disappeared. Then they were intracoronarily infused with ECIII-60 at 0.0025 mmol/kg and imaged for 5 hr. Signal intensity, infarct-over-normal contrast ratio and relative infarct size were quantified, compared, and correlated with the results of postmortem MRI and triphenyltetrazolium chloride (TTC) histochemical staining. Results. A contrast ratio over 3.0 was induced by both Gd-DTPA and ECIII-60. However, while the delayed enhancement with Gd-DTPA virtually vanished in 1 hr, ECIII-60 at an 80x smaller dose depicted the MI accurately over 5 hr as proven by ex vivo MRI and TTC staining. Conclusion. Both Gd-DTPA and ECIII-60 strongly enhanced acute MI. Comparing with fading contrast in a narrow time window with intravenous Gd-DTPA, intracoronary ECIII-60 persistently demarcated the acute MI, indicating a potential method for postprocedural assessment of myocardial viability after coronary interventions