Optimizing Leakage Energy Consumption in Cache Bitlines

As technology scales down into deep-submicron, leakage energy is becoming a dominant source of energy consumption. Leakage energy is generally proportional to the area of a circuit and caches constitute a large portion of the die area. Therefore, there has been much effort to reduce leakage energy in caches. Most techniques have been targeted at cell leakage energy optimization. Bitline leakage energy is critical as well. To this end, we propose a predictive precharging scheme to reduce bitline leakage energy consumption. Results show that energy savings are significant with little performance degradation. Also, our predictive precharging is more beneficial in more aggressively scaled technologies.     

The effect of aggregation on the nonlinear optical absorption performance of indium and gallium phthalocyanines in a solution and co-polymer host

The nonlinear optical properties (NLO) of Pcs can be modified by substituting different metal atoms into the ring or altering peripheral and axial functionalities. In this study, nonlinear optical absorption properties of tetra-substituted gallium and indium phthalocyanine complexes both in solution and polymeric film have been investigated by open aperture Z-scan measurements with nanosecond pulses at 532 nm. All investigated compounds exhibited reverse saturable absorption for both solution and film experiments. The investigated compounds in the solution showed better nonlinear optical absorption properties than polymeric films. The observed nonlinear optical absorption differences depending on the aggregation are discussed using the ultrafast dynamics and decay processes of excited states found from femtosecond pump-probe spectroscopy with white light continuum experiments.     

Process parameters for hydrocooling apricots, plums, and peaches

Freshly harvested apricots, plums, and peaches in crates containing 5–20kg were hydrocooled in flowing water at 1°C and 50mms^-1. The cooling parameters: lag factor, cooling coefficient, and time to half-cool, determined from the exponential decline in the dimensionless ratio of temperature differences between fruit centre and coolant temperature at time t and at zero time, varied somewhat with crate load. Increasing the load from 5 to 20kg increased the time to half-cool apricots by 17% and plums and peaches by 39%.     

Prediction of Excess Air Factor in Automatic Feed Coal Burners by Processing of Flame Images

In this study, the relationship between the visual information gathered from the flame images and the excess air factor k in coal burners is investigated. In conventional coal burners the excess air factor k. can be obtained using very expensive air measurement instruments. The proposed method to predict k for a specific time in the coal burners consists of three distinct and consecutive stages; a) online flame images acquisition using a CCD camera, b) extraction meaningful information(flame intensity and brightness)from flame images, and c) learning these information(image features) with ANNs and estimate k. Six different feature extraction methods have been used: CDF of Blue Channel, Co-Occurrence Matrix, L_∞-Frobenius Norms,Radiant Energy Signal(RES), PCA and Wavelet. When compared prediction results, it has seen that the use of cooccurrence matrix with ANNs has the best performance(RMSE = 0.07) in terms of accuracy. The results show that the proposed predicting system using flame images can be preferred instead of using expensive devices to measure excess air factor in during combustion.     

Synthesis and characterization of polyurethanes containing glucose for selective determination of epinephrine in the presence of a high concentration of ascorbic acid

Polyurethane (PU) films were prepared from glucose, ethylene glycol and diphenylmethane diisocyanate and used to construct a novel polymer electrode for the detection of epinephrine (EP) in the presence of a high concentration of ascorbic acid (AA). The NCO:OH molar ratio was kept constant at 1 and the saccharide content was varied. The PUs were characterized using Fourier transform infrared spectroscopy, differential scanning calorimetry and differential thermal and thermogravimetric analyses, with intrinsic viscosity and adhesive properties also being evaluated. The PUs exhibited high glass transition temperature, good thermal stability and good adhesive properties. The incorporation of saccharides into the PU structure resulted in a higher crosslinking density and a higher content of hard segments. Medium‐ to high‐molecular‐weight polymers were obtained, with inherent viscosities near or higher than 0.98–2.14 dL g^?1. The solubility of the PUs was much better than that of aromatic PUs. The modified polymer electrodes were then used to determine EP in the presence of a high concentration of AA using differential pulse voltammetry. From the amperometric results for the PU electrode, it is concluded that a PU film containing 5 wt% glucose can be used as a membrane for EP detection in the presence of a large concentration of AA, because of its strong adherence to the electrode surface, easy preparation, chemical stability, selectivity and very high statistical confidence (R = 0.9994). © 2012 Society of Chemical Industry     

A supramolecular sensing platform for phosphate anions and an anthrax biomarker in a microfluidic device

A supramolecular platform based on self-assembled monolayers (SAMs) has been implemented in a microfluidic device. The system has been applied for the sensing of two different analyte types: biologically relevant phosphate anions and aromatic carboxylic acids, which are important for anthrax detection. A Eu(III)-EDTA complex was bound to β-cyclodextrin monolayers via orthogonal supramolecular host-guest interactions. The self-assembly of the Eu(III)-EDTA conjugate and naphthalene β-diketone as an antenna resulted in the formation of a highly luminescent lanthanide complex on the microchannel surface. Detection of different phosphate anions and aromatic carboxylic acids was demonstrated by monitoring the decrease in red emission following displacement of the antenna by the analyte. Among these analytes, adenosine triphosphate (ATP) and pyrophosphate, as well as dipicolinic acid (DPA) which is a biomarker for anthrax, showed a strong response. Parallel fabrication of five sensing SAMs in a single multichannel chip was performed, as a first demonstration of phosphate and carboxylic acid screening in a multiplexed format that allows a general detection platform for both analyte systems in a single test run with μM and nM detection sensitivity for ATP and DPA, respectively.     

Upgrading of iron ores using microwave assisted magnetic separation followed by dephosphorization leaching

This paper describes the development of a flowsheet using a combination of sample preparation, magnetic separation (in a range 0.4–1?T), microwave treatment (in a range 0.54–0.9?kW), and leaching operations (HCl, in a range 0.25–1.25?M) for the beneficiation of iron ores (Total Fe [T_FE]: 55.48%). The work was aimed at recovering T_FE from the non-magnetic product by increasing its magnetic susceptibility through microwave treatment. It was found that goethite mineral in the non-magnetic product at a temperature of around 200^oC was converted to paramagnetic (hematite) or ferromagnetic minerals (maghemite and magnetite) by microwave treatment and overall beneficiation recovery was improved. The phosphorus (P) content in the final product was then removed by leaching in 0.25?M HCl. The iron loss from the final concentrate during leaching was found to be 0.78%, which was negligible. Overall, a final concentrate assaying 61.78% T_FE with a recovery of 94.97%, and containing 0.04% P with 94.73% removal was obtained providing satisfactory results for use in the industry. This study gives an alternative way for possible future studies to produce an iron concentrate with a high recovery from problematic iron ores, which can be categorised due to its P content.     

Memory Partitioning in the Limit

International Journal of Parallel Programming - The key difficulties in designing memory hierarchies for future computing systems with extreme scale parallelism include (1) overcoming the design...     

玻璃光波导元件检测氯仿蒸汽的研究

利用旋转甩涂法在钾离子交换玻璃光波导表面上固定甲基绿/聚乙烯醇薄膜，成功地检测氯仿蒸汽。实验结果表明，该元件对氯仿蒸汽有良好的响应，其线性响应范围为10×10^-3-90×10^-3（R=0.98674）。该元件具有响应恢复速度快、可逆性好、成本低和易制备等特点。