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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.

Three new tailor-made molecules (DPDCTB, DPDCPB, and DTDCPB) were strategically designed and convergently synthesized as donor materials for small-molecule organic solar cells. These compounds possess a donor-acceptor-acceptor molecular architecture, in which various electron-donating moieties are connected to an electron-withdrawing dicyanovinylene moiety through another electron-accepting 2,1,3-benzothiadiazole block. The molecular structures and crystal packings of DTDCPB and the previously reported DTDCTB were characterized by single-crystal X-ray crystallography. Photophysical and electrochemical properties as well as energy levels of this series of donor molecules were thoroughly investigated, affording clear structure-property relationships. By delicate manipulation of the trade-off between the photovoltage and the photocurrent via molecular structure engineering together with device optimizations, which included fine-tuning the layer thicknesses and the donor:acceptor blended ratio in the bulk heterojunction layer, vacuum-deposited hybrid planar-mixed heterojunction devices utilizing DTDCPB as the donor and C(70) as the acceptor showed the best performance with a power conversion efficiency (PCE) of 6.6 ± 0.2% (the highest PCE of 6.8%), along with an open-circuit voltage (V(oc)) of 0.93 ± 0.02 V, a short-circuit current density (J(sc)) of 13.48 ± 0.27 mA/cm(2), and a fill factor (FF) of 0.53 ± 0.02, under 1 sun (100 mW/cm(2)) AM 1.5G simulated solar illumination.

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.

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Heterogeneous CPU-GPU systems have recently emerged as an energy-efficient computing platform. A robust integrated CPU-GPU simulator is essential to facilitate researches in this direction. While few integrated CPU-GPU simulators are available, similar tools that support OpenCL 2.0, a widely used new standard with promising heterogeneous computing features, are currently missing. In this paper, we extend the existing integrated CPU-GPU simulator, gem5-gpu, to support OpenCL 2.0. In addition, we conduct experiments on the extended simulator to see the impact of new features introduced by OpenCL 2.0. Our OpenCL 2.0 compatible simulator is successfully validated against a state-of-the-art commercial product, and is expected to help boost future studies in heterogeneous CPU-GPU systems.