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Graphene-based film heaters (GFHs) with laser-patterned electrode structures can be used in microheaters, thermal sensors, and thermostatic apparatuses for various high-value-added medical devices and creative products. To obtain uniform and higher temperatures, this study aims to design, fabricate, and measure GFHs with net-like electrode structures using ANSYS Workbench software, an ultraviolet laser processing system, and an infrared thermal imaging camera, respectively. The electric heating experiments (which were measured with an infrared thermal imaging camera) demonstrated that the temperatures of GFHs with net-like electrode structures were significantly higher than those of devices without patterned graphene films. Moreover, the temperatures of GFHs with net-like electrode structures increased rapidly with time when DC voltages higher than 12 V were applied for at least 10 s. A maximum temperature of 91.5 °C was obtained at 200 s when a DC voltage of 18 V was applied. Besides, minimal and maximal deviations of steady-state temperatures between experimental and simulated values were 6.9 °C and 10 °C under each corresponding DC voltage, respectively.

A microalgae-based energy system, which is a combination of different microalgae-to-biodiesel chains and an integrated cogasification combined cycle (ICGCC) system, is presented. To address the low environmental impacts, the electricity is generated from ICGCC to meet the load demand from the microalgae-to-biodiesel chains and the flue gas exits from ICGCC to meet the demand of growing algal culture. To achieve the microalgae-based energy system with minimum life cycle greenhouse gas (GHG) emissions, the first step is to develop the superstructure model based on GAMS, the second step is to use the optimal heat exchanger network to maximize the heat recovery of ICGCC, and the third step is to find the optimal combination of the microalgae-to-biodiesel chain and optimal operating conditions of ICGCC by solving the global optimization of nonconvex mixed-integer nonlinear programming (MINLP) problem. For the scope of well-to-tank (WTT), the optimal microalgae-based energy system reduces 16.80% greenhouse gas (GHG) emissions compared to the other reported microalgae-to-biodiesel chains. For the scope of well-to-wheel (WTW), the optimal microalgae-based energy system reduces 45.77% GHG emissions compared to the conventional diesel process.

Accelerator-rich architectures employ IOMMUs to support unified virtual address, but researches show that they fail to meet the performance and energy requirements of accelerators. Instead of optimizing the speed/energy of IOMMU address translation, this work tackles the issue from a new perspective, eliminating the need for translation with an active forwarding (AF) mechanism that forwards input data of accelerators directly from the CPU cache to the scratchpad memory of the accelerator. Results show that on average, AF can provide 8% performance improvement compared to the state-of-the-art mechanism, hostPageWalk, and reduce 22.1% accelerator power.

Emergency power supply facilities and loads connected by long power cables are becoming increasingly common in industrial power systems. System facilities connection via a power cable introduces a considerably significant shunt capacitance to the source power system, giving rise to low natural or resonant frequency. One source of harmonic currents is the system transformer. When initially energized, the transformer may draw a transient inrush current that contains all harmonic components. If one of the harmonic components in the inrush current is close to the resonant frequency of the power system depending upon the damping levels, a sustained overvoltage may be produced. This has recently caused operational problems on a number of newly emergency power systems for mass rapid transit. This paper presents the methodology and results that assist industrial power system restoration switching with regards to control of harmonic overvoltages due to transformer energization. Analysis tools and methodologies are presented in this paper that can be used during detailed engineering design to assess the likelihood of such dangerous events and to identify whether mitigation is required, long before the problems are encountered during system commissioning.

In this work, we report a simple method for solution-processed organic light emitting devices (OLEDs), where single-layer graphene acts as the anode and the hexa-peri-hexabenzocoronene exfoliating agent (HBC-6ImBr) provides surface modification. In SEM images, the PEDOT:PSS solution fully covered the graphene electrode after coating with HBC-6ImBr. The fabricated solution-processed OLEDs with a single-layer graphene anode showed outstanding brightness at 3182 cd/m2 and current efficiency up to 6 cd/A which is comparable to that of indium tin oxide films, and the OLED device brightness performance increases six times compared to tri-layer graphene treated with UV-Ozone at the same driving voltage. This method can be used in a wide variety of solution-processed organic optoelectronics on surface-modified graphene anodes.