Power Mitigation by Performance Equalization in a Heterogeneous Reconfigurable Multicore Architecture

This paper presents an integrated self-aware computing model mitigating the power dissipation of a heterogeneous reconfigurable multicore architecture by dynamically scaling the operating frequency of each core. The power mitigation is achieved by equalizing the performance of all the cores for an uninterrupted exchange of data. The multicore platform consists of heterogeneous Coarse-Grained Reconfigurable Arrays (CGRAs) of application-specific sizes and a Reduced Instruction-Set Computing (RISC) core. The CGRAs and the RISC core are integrated with each other over a Network-on-Chip (NoC) of six nodes arranged in a topology of two rows and three columns. The RISC core constantly monitors and controls the performance of each CGRA accelerator by adjusting the operating frequencies unless the performance of all the CGRAs is optimally balanced over the platform. The CGRA cores on the platform are processing some of the most computationally-intensive signal processing algorithms while the RISC core establishes packet based synchronization between the cores for computation and communication. All the cores can access each other’s computational and memory resources while processing the kernels simultaneously and independently of each other. Besides general-purpose processing and overall platform supervision, the RISC processor manages performance equalization among all the cores which mitigates the overall dynamic power dissipation by 20.7 % for a proof-of-concept test.     

Joint optimization of energy and delay for computation offloading in cloudlet-assisted mobile cloud computing

Wireless Networks - In the mobile cloud computing (MCC), although offloading requests to the distant central cloud or nearby cloudlet can reduce energy consumption at the mobile devices (MDs), it...     

Parallel plate heat exchanger for heat energy recovery in a farm grain dryer

One of the methods with the most potential to reduce energy consumption in grain drying is heat recovery from the dryer exhaust air. A parallel plate heat exchanger to recover heat energy from the exhaust air of a recirculating batch grain dryer was examined by theoretical assessments as well as by measurements in a scaled-down research dryer and experimental heat exchanger. In addition to the heat transfer performance, the operability in dusty conditions was investigated. Finally, the optimization of the heat exchanger was introduced by the aid of the calculation models and practical measurement. The heat exchanger performed satisfactorily, providing an average energy saving of approximately 18%. A significant improvement in the performance could be achieved by increasing the air velocity. No severe dust accumulation was observed, and a heat exchanger of this type could provide remarkable energy saving possibilities in grain drying. Further tests are necessary to ensure the operability in long-term use.     

Thin films of MoN, WN, and perfluorinated silane deposited from dimethylamido precursors as contamination resistant coatings on micro-injection mold inserts

To enhance their surface properties, micro-injection mold inserts made of electroplated nickel were coated with thin films of molybdenum nitride and tungsten nitride by atomic layer deposition. Alkylimido-alkylamido complexes were used as precursors together with ammonia. In addition, a perfluorinated hydrophobic coating was deposited by gas-phase method from tridecafluoro-1,1,2,2-tetrahydrooctylmethyl-bis(dimethylamido)silane. Injection molding tests were performed with two plastic materials: poly(4-methyl-1-pentene) copolymer TPX™ and polycarbonate Makrolon® DP1-1265. With both plastics, the nickel insert with thin film of molybdenum nitride was clearly more resistant to contamination than the uncoated insert. Also the perfluorosilane coating provided good resistance to contamination. After the 15,000 shot injection molding test, all of the coatings were still attached to the insert. Friction coefficients were determined between the nitride and silane coatings and the plastic materials. The coatings showing good contamination resistance in injection molding also had a low coefficient of friction.     

A Dynamic Calibration Method for Crusher Gauges Based on Material Testing

This paper presents a new dynamic calibration method for crusher pressure gauges used in artillery test firings. The calibration method is based on the measurement of the plastic deformation behavior of the crusher elements in the laboratory completely isolated from test firings and measurements by reference pressure transducers. The validity of the calibration model developed is verified by comparison with the pressure records measured in artillery test firings. It was found that the calibration method developed is also suitable for the high load levels and strain rates present in tank firings.     

A nanostructured electrochromic supercapacitor

We report the first successful application of an ordered bicontinuous double-gyroid vanadium pentoxide network in an electrochromic supercapacitor. The freestanding vanadia network was fabricated by electrodeposition into a voided block copolymer template that had self-assembled into the double-gyroid morphology. The highly ordered structure with 11.0 nm wide struts and a high specific surface to bulk volume ratio of 161.4 μm(-1) is ideal for fast and efficient lithium ion intercalation/extraction and faradaic surface reactions, which are essential for high energy and high power density electrochemical energy storage devices. Supercapacitors made from such gyroid-structured vanadia electrodes exhibit a high specific capacitance of 155 F g(-1) and show a strong electrochromic color change from green/gray to yellow, indicating the capacitor's charge condition. The nanostructuring approach and utilizing an electrode material that has intrinsic electrochemical color-change properties are concepts that can be readily extended to other electrochromic intercalation compounds.     

HARP2: An X-Scale Reconfigurable Accelerator-Rich Platform for Massively-Parallel Signal Processing Algorithms

This paper presents design, development and evaluation of an eXtra-large Scale, Homogeneous and a Heterogeneous Accelerator-Rich Platform (HARP²) for massively parallel signal processing algorithms. HARP is an integrated platform of multiple Coarse-Grained Reconfigurable Arrays (CGRAs) over a Network-on-Chip (NoC) where each CGRA is scaled and tailored for a specific application. The architecture of the NoC consists of nine nodes in a topology of 3-rows × 3-columns and acts as backbone of communication between different CGRAs. In this experimental work, the HARP template is used to instantiate a homogeneous (HARP-hom) and a heterogeneous (HARP-het) platform. The HARP-het is generated for a proof-of-concept test to verify the design and functionality of HARP. It also provides insight to many features of the design and evaluation in terms of different performance metrics. The other version (HARP-hom) is instantiated for a relatively realistic design problem, i.e., satisfying the execution-time constraints imposed on Fast Fourier Transform processing in IEEE-802.11n demodulators. Both of the versions of HARP are treated for comparative analysis using different performance metrics against some of the existing state-of-the-art platforms. The HARP versions are designed to illustrate large-scale homogeneous/heterogeneous multicore architectures while presenting the advantages of maximizing the number of reconfigurable processing resources on a single chip.     

Blanching and long‐term freezing affect various bioactive compounds of vegetables in different ways

An extensive study on the effects of blanching/freezing and long‐term freezer storage on various bioactive compounds of more than 20 commonly used vegetables was performed. Effects were strongly plant species‐dependent. Contents of dietary fibre components either were not affected or increased slightly. Minerals in general were also stable, but some losses of soluble minerals by leaching were observed. Phenolic antioxidants and vitamins were clearly more sensitive. Significant losses (20–30%) of antioxidant activity and total phenolics were detected in many vegetables. A qualitative HPLC profiling method for phenolic antioxidants was developed which proved to be very useful when evaluating the complex behaviour of phenolics during food processing. Up to one‐third of vitamin C contents were lost during blanching, and further slight losses were detected during storage. Folic acid turned out to be very sensitive to blanching, with more than half of the vitamin being lost, but was stable during freezer storage. Carotenoids and sterols were not affected by blanching or freezer storage. The usefulness of the applied screening methods for evaluation of the effects of processing on vegetables is shown. Copyright © 2003 Society of Chemical Industry     

Repair and replacement of reactor internals for plant life extension

Recent experience from early Swedish BWRs corroborate that all components in a nuclear power plant can be repaired or replaced with new ones. Oskarshamn 1 has gone through a thorough refurbishment project. A number of internals were repaired or replaced including the core shroud support which was welded to the bottom of the reactor pressure vessel. The project verifies that it is fully possible to carry out complicated inspection and repair work inside a nuclear pressure vessel which has been in operation for more than 20 years. Along with increased capacity factor, operating nuclear power plants get the financial conditions needed for extensive repair and modernization projects. Large power output leads to short pay-back times for the investments. The FENIX project at Oskarshamn 1 is such a project. There are utilities whose policy is to keep their plants in as-new condition for an unlimited length of time.