bluuebunny/crossref_metadata_2025 huggingface dataset:
Limited Area Air Quality Modeling in Geographic Scale Through Flow Field Validation in Hilly Terrain
Authors: Jana R. , Rajagopal P. S. , Kumar A. Vinod , Puranik V. D. , Runchal A.
Published: December 2013

The turbulent motion of atmosphere adjoined to the earth’s surface is caused by the surface friction and buoyancy force in a short time scale which is of the order of few seconds to minutes. This interactive layer is atmospheric boundary layer with several detailed features viz., roughness layer, surface layer for small eddies, mixed layer for large eddies, which may extend vertically more than a kilometer under deep convective condition. The surface layer is primarily characterised through several scaling parameters, viz., roughness length, momentum flux and sensible heat flux as triggering force of turbulence and its maintenance through eddy formation and dissipation. Air dispersion and hence the distribution of atmospheric pollutants from various sources follow flow path and its turbulent characteristics, which is dependent on geometry of the terrain specially for complex terrain, meteorological conditions and source term inventories. In the present study, an virtual environment is designed in a computational fluid dynamics based solver for limited area/local scale air quality modelling by incorporating digital elevation model of intermediate valley zone of Sahyadri Range of Western Ghats of India as site. Finite volume method and mass flux transfer approach is followed by the solver to estimate 3D atmospheric or ground level concentration of atmospheric non-reactive pollutants for unit discharge per second from a hypothetical 100 m tall stack for 72 hours. Flow field is computed for various realistic cases for which initial and boundary conditions are incorporated from larger scale model, viz., Mesoscale Model (MM5) developed by the National Centre for Atmospheric Research, USA and also from measured local data taken from distributed micro-meteorological observatories. Computed flow field is validated with independent observation not utilised in computation giving a validation to the estimated contaminant concentration so. The uncertainty in diffusion is also studied when Lagrangian particle movement is driven fully by flow field and its turbulent phenomena in comparison to random walk model.
Statistical Based Estimation of Biporous Evaporator Dryout
Authors: Reilly Sean , Catton Ivan
Published: December 2013

Biporous wicks are an effective means for facilitating evaporation in heat pipes used for electronics cooling. They facilitate boiling within the wick by having two distinct size distributions of pores; the smaller pores provide high capillary pressure to pump liquid to the surface while the larger pores maintain high vapor permeability. The wicks investigated in this study were sintered copper biporous material. The authors previously presented a validated statistical model, based on work by Kovalev, which could predict the performance of biporous wicks tested at UCLA with reasonable accuracy [1]. Using this model, the author was able to gain new insight into the effect that the numerical estimate of liquid saturation of the wick has on dry out. The pore size distribution allows the determination of the capillary pressure available inside the wick and the Kovalev model provides the required pressure drop to supply liquid water to the heater surface. This led to a method of predicting dry out by comparing the capillary pressure in the wick to the required pressure drop from the model to estimate when the wick was dried out.

When the required pressure drop determined by code exceeds the peak effective capillary pressure provided by the wick, the large pores of the wick are considered to be dry. These values are correlated to the input heat flux to determine what at what input power the wick begins to dry out. While the wick will not fail in this mode, the overall heat transfer coefficient will have peaked. In this work, this method of determining dry out will be validated against wicks tested at UCLA by comparing the input powers at which this dry out phenomenon occurs. Accurate predictions of dry out and the role of the pore size distribution are critical in developing methods to delay dry out of biporous wicks. By comparing the relative dry out points of various wick geometries to each other, augmented wick geometries can be suggested for future work. This modeling tool can lay the foundation for future tailoring of biporous evaporator wicks to specific tasks.
Flow and Heat Transfer From the Annular Fin Heat Exchanger Using Winglet Type Vortex Generators
Authors: Rana Basanta Kumar , Dalal Amaresh , Biswas Gautam
Published: December 2013

A numerical study of three-dimensional flow and heat transfer from the annular finned tube heat exchanger with built-in delta winglets is carried out. The delta winglets type vortex generators which are placed on the annular fin surface in the neighborhood of the cylinder are used to enhance the heat transfer. The winglets are placed in common flow orientation. Longitudinal vortices develop along the side edge of the delta winglets due to the pressure difference between the front surface (facing the flow) and back surface. These vortices interact with thermal boundary layer and produce a three dimensional swirling flow that mixes near wall fluid with the midstream. Thus the thermal boundary layer is disrupted and heat transfer is enhanced. The investigations are carried out for four different Reynolds number (100, 500 and 1000) and four different angles of attack (35°, 40°, 45°, 50°) for common flow up (CFU) configuration. It is found that heat transfer increases about 11% for Re = 1000 with angle of attack 40°.
Transient Thermal Analysis for the Automotive Underhood and Underbody Components
Authors: Wu Yu Hsien , Srinivasan Kumar , Patterson Steven , Bot Emmanuel
Published: December 2013

The transient thermal simulation is an important part of thermal management development for new vehicle architectures. Different techniques have been studied in the past to address this coupled conduction/convection/radiation problem. In order to fully capture the transient thermal behavior of various underhood and underbody components, it is also necessary to accurately model the thermal mass of each part and the thermal links between dissimilar materials. The paper will outline a new, efficient methodology for this type of thermal analysis that shows acceptable results for complex full vehicle thermal analysis without sacrificing accuracy. The methodology is based on approximating the transient convective field with intermittent steady state solutions. The paper will present results from this new approach and compare them with fully transient simulation results as well as experimental data. The new methodology can be optimized to significantly reduce simulation run times without sacrificing accuracy and to be more practical for application in the vehicle development cycle.
Ammonia as a Byproduct of Waste Heat Recovery of Oven Exhaust
Authors: Skop Helen , Chudnovsky Alice
Published: December 2013

The Industrial Revolution in the nineteenth century has introduced chemical leavening agents such as baking soda. In today’s Biscuit and Cracker Industry, ammonia is one of the most common ingredients for the bakery product. According to the EPA, ammonia vapor constitutes about 99% of total emissions from a biscuit oven. Air control equipment, such as catalytic oxidizers, is often installed at bakeries to convert the NH3 to nitrogen and NOx. It is a highly expensive and complicated method of controlling pollution. Integration of waste heat recovery and ammonia extraction processes gives us an effective, non-expensive and more natural solution to this problem. This method can be accomplished by using the solubility property of ammonia for the process of exhaust cooling and condensation with high moisture content.
Progress in the Computation of Turbulent Heat Transfer in Massively Separated Flows
Authors: Younis B. A. , Arnold B. , Weihing P. , Weigand B.
Published: December 2013

The paper reports on work in progress aimed at improving the prediction of heat transfer in turbulent separated flows. The cases considered here are the flow over a heated backward-facing step, and the periodic flow in a heated channel with square ribs. The predictions were obtained using two models not hitherto employed in these flows: a Reynolds-stress transport closure in which the model for the fluctuating pressure-strain correlations that satisfies the requirement of model objectivity while not requiring wall-damping functions, and a model for the turbulent heat fluxes that is explicit, algebraic and correctly allows for these fluxes to depend on the gradients of mean temperature and velocity. Both models have previously given good predictions in attached shear flows and the objective of this work was to determine whether this improvement carries over to separated flows. It was found that distinct improvements in the prediction of skin friction and Nusselt number can only be obtained by extending the models so as to allow the computations to extend through the viscous sub-layer directly to the wall.
Multi-Jet Flows Underneath Small Bubble in Nucleate Boiling of Subcooled Self-Rewetting Fluid
Authors: Zhou Leping , Li Yuanyuan , Wei Longting , Du Xiaoze
Published: December 2013

Jet flow phenomenon is important in enhanced nucleate boiling heat transfer processes and applications. When heater sizes scale down, jet flow can be observed due to the Marangoni convection around bubbles staying on microscale heated surface. In this paper, two fluids were employed for comparing and demonstrating the effect of Marangoni convection on bubble behaviors on micro heating wire. One was ultrapure water and the other was aqueous n-butanol solution, a self-rewetting fluid. Bubble-top jet flow for water and multi-jet flows for n-butanol solution were observed around a platinum micro heating wire by high speed CCD camera. Corresponding numerical simulation proved that it is the Marangoni convection that attracts the sub-cooled water to flow from the super-heated microlayer at the bottom to the top of a stationary bubble. For n-butanol solution, however, the Marangoni convection can induce it to flow oppositely, which causes the subcooled solution to flow onto the heated surface. The simulation for the solution is in good agreement with the experiment where the subcooled liquid nears the bubble-top flow towards the bottom of bubble or the heated surface and hence the multi-jet flows occur. The multi-jet flows can sustain for a long period and cause transient chaos at the super-heated thin liquid layer near the heated surface. The temperature around the bubble presented sharp temperature gradient and the velocity in the near-wall region is almost vertical to the wall. The experimental and numerical studies on the effect of surface tension and thus Marangoni convection are crucial to the mechanisms of subcooled nucleate boiling of fluids.
Controlling the Leidenfrost Temperature Through Laser-Assisted Surface Micro/Nano Texturing
Authors: Kruse Corey , Anderson Troy , Alexander Dennis , Gogos George , Ndao Sidy
Published: December 2013

In the present work, the effect of surface features and wettability on the Leidenfrost temperature are experimentally investigated. The surface features were fabricated on a 304 stainless steel surface using a femtosecond laser. This technique allows for a wide variety of surface microstructures (spikes, mounds, holes, and pyramids) to be created, ranging in size, shape, and spacing. Changing the fluence and shots of the laser produce different micro/nano textured surfaces. A smooth surface sample was fabricated as a reference surface with a measured Leidenfrost temperature as a benchmark. The droplet lifetime experimental method was employed to determine the Leidenfrost temperature for both the smooth and the textured surfaces. A precision dropper was used to control the droplet size to 4.2 microliters (diameter of 2.0mm) while surface temperatures were measured by means of an embedded thermocouple. In comparison to the smooth stainless steel surface, a shift in the Leidenfrost temperature, as high as 55 °C, was observed with the textured surface. The textured surface hasa high emissivity, compared to the smooth surface. As a result, in addition to the shift in the Leidenfrost temperature, significant enhancement of the film boiling heat transfer coefficients were also observed.
A Novel Inorganic Aqueous Solution and its Effect on Liquid Spreading and Freeze/Thaw Processes
Authors: Supowit Jacob , Reilly Sean , Amouzegar Ladan , Catton Ivan
Published: December 2013

Frozen startup of phase change heat transfer devices is a complex problem that can have a large impact on heat transfer systems. A patented novel working fluid developed at UCLA comprised of an inorganic aqueous solution (IAS) was investigated for potential effects on the freeze/thaw capabilities in phase change heat transfer devices by examining the melting process of droplets. Preliminary visual tests were conducted to gain insight into any physical processes that surface augmentation created by this fluid may have on the freezing and melting process. These tests demonstrated significant differences in liquid spreading, the melting process, and the melting rate of droplets on surfaces pre-treated with IAS. Contact angle measurements exhibited enhanced wetting properties. SEM images of frozen droplets showed that liquid freezes in the small capillary wick formed by the initial evaporation of IAS. Video of melting droplets showed a significant increase in melting rate when the surface was first treated with IAS due to superior liquid spreading.
Heat Transfer Through Small Moveable Gas Gaps in a Multi-Body System Using the ANSYS Finite Element Software
Authors: McDuffee Joel L.
Published: December 2013

The Thermal Hydraulics and Irradiation Engineering (THIE) Group at Oak Ridge National Laboratory (ORNL) designs and builds capsules in which to irradiate advanced fuels and materials that are typically inserted into ORNL’s High Flux Isotope Reactor. Experiments are designed to achieve a target temperature that ranges from 250°C to 1200°C. Most capsules do not have active temperature measurement or control, which puts an imperative on accurate temperature simulation. Temperature control in these capsules is accomplished by designing specific gaps between adjacent parts and filling the capsules with an inert gas: helium, neon, or argon.

Most any finite element solver will do an excellent job estimating temperatures within individual parts, but the simulation challenge for these complex, multi-body systems is to accurately predict the heat transfer through contact surfaces or interstitial gas gaps. The gas gaps are on the order of 150 μm, so accurate simulation must include thermal expansion of the adjacent parts, the thermal jump effect on the part surfaces, and the possibility the parts will touch or break contact during expansion. This paper will discuss the limitations in thermal contact modeling in finite element modelers and the algorithms the THIE Group uses to overcome these limitations.
Use of a Two-Phase Thermosyphon as a Low-Cost, High-Performance Economizer for Refrigeration Systems
Authors: He Tao , Mei Chunlei , Butcher Tom , Longtin Jon P.
Published: December 2013

The electricity consumption of residential and commercial refrigerators is significant in the United States. A natural choice then is to use the low outside temperatures for cooling to reduce electricity usage for residential refrigerators. Our solution is to use two phase close thermosyphon as an economizer during the cold season to take advantage of colder outside temperatures. Benefits of the thermosyphon include a high heat carrying capability with a small temperature drop, low cost, and the ability to behave as a thermal diode. In this work, a model is adapted from the literature to investigate the effect of working fluids, filling ratio and heat input on the performance of thermosyphon for refrigeration applications. Among the working fluids explored ammonia provided the best performance, followed by methanol. Experimental results are also presented for a thermosyphon residing in a simulated refrigeration configuration. The measured temperatures agree well with model predictions. The result demonstrates it is able to maintain temperature drop with applicable range.
Heat Transfer Augmentation in Convecting Film Flows
Authors: Mathie Richard , Markides Christos N.
Published: December 2013

The manifestation of unsteady heat transfer in incompressible forced convecting flows, such as film flows, is of direct practical interest to a large number of important industrial applications, such as film evaporators and reactors. In this paper an attempt is made to improve our fundamental understanding of unsteady heat transfer in these flows, and to predict this phenomenon by developing a reduced model of the specific case of a film flow over a heated solid. A time-varying heat transfer fluctuation is imposed, caused by a feature or disturbance that convects freely with the flow. The energy equation is solved to obtain the fluid’s thermal development, while a conjugate boundary condition comprising a one-dimensional thermal interaction between the fluid and the contacting solid substrate is imposed. Two heat transfer behaviours are found, which are referred to as “under-damped” and “damped”. Their characteristics with regards to the thermal development of the investigated flows are studied, including a consideration of heat transfer “augmentation” (relative to equivalent steady flows). Augmentation is found to remain negative for all investigated conditions.
Oil Effects on In-Tube Evaporation of CO2 by Altering Flow Regime and Properties
Authors: Hrnjak Pega , Kim Seongho
Published: December 2013

Flow boiling heat transfer characteristics of CO2 with and without oil were investigated experimentally in horizontal smooth and enhanced tubes with an inner diameter of 11.2 mm. The visualization of flow pattern provides a detailed attributes of the nucleate and the convective boiling heat transfer. In order to investigate the effect of the miscible oil on the heat transfer of CO2, POE (polyolester) RENSIO C85E oil is added to give an oil circulation rate (OCR) between 0.5% and 2%. Results are compared with those of pure CO2. The experimental conditions include evaporation temperatures of −15 °C, mass fluxes from 40 to 200 kg/m2 s, heat fluxes from 0.5 to 10 kW/m2, and vapor qualities from 0.1 to 0.8. Oil generally deteriorates the heat transfer coefficient of pure CO2. The reduction in heat transfer coefficient is most apparent at low vapor qualities, 0.1 to 0.4, and at low mass fluxes, 100 and 200 kg/m2. It is caused by the suppression of nucleate boiling due to increased surface tension. At conditions where the convective boiling contribution is dominant, vapor qualities above 0.5, oil increases heat transfer coefficients. Through visualization, it is shown that the wetted area on the perimeter of inner tube is enhanced due to formation of foaming in the smooth tube. However, such enhancement of heat transfer due to forming is negligible in the enhanced tube, because the enhanced factor due to micro-finned structures is dominant.
Ubiquitous Interplay Between Charge Ordering and High-Temperature Superconductivity in Cuprates
Authors: da Silva Neto Eduardo H. , Aynajian Pegor , Frano Alex , Comin Riccardo , Schierle Enrico , Weschke Eugen , Gyenis András , Wen Jinsheng , Schneeloch John , Xu Zhijun , Ono Shimpei , Gu Genda , Le Tacon Mathieu , Yazdani Ali
Published: December 2013

Besides superconductivity, copper-oxide high-temperature superconductors are susceptible to other types of ordering. We used scanning tunneling microscopy and resonant elastic x-ray scattering measurements to establish the formation of charge ordering in the high-temperature superconductor Bi
2
Sr
2
CaCu
2
O
8+x
. Depending on the hole concentration, the charge ordering in this system occurs with the same period as those found in Y-based or La-based cuprates and displays the analogous competition with superconductivity. These results indicate the similarity of charge organization competing with superconductivity across different families of cuprates. We observed this charge ordering to leave a distinct electron-hole asymmetric signature (and a broad resonance centered at +20 milli–electron volts) in spectroscopic measurements, indicating that it is likely related to the organization of holes in a doped Mott insulator.
Draft Genome Sequence of Ralstonia solanacearum Race 4 Biovar 4 Strain SD54
Authors: Shan Weiwei , Yang Xiaohui , Ma Weiqing , Yang Yu , Guo Xiao , Guo Jianhua , Zheng Huajun , Li Guangcun , Xie Bingyan
Published: December 2013

Ralstonia solanacearum
is an important etiological agent that can cause serious bacterial wilt in a very wide range of potential host plants, including ginger. Here, we report the complete genome sequence of
R. solanacearum
SD54, a race 4 biovar 4 (R4B4) strain from a diseased ginger plant in China.
Draft Genome Sequence of a Multidrug-Resistant New Delhi Metallo-β-Lactamase-1 (NDM-1)-Producing Escherichia coli Isolate Obtained in Singapore
Authors: Xia Eryu , Khong Wei Xin , Marimuthu Kalisvar , Xu Wenting , Ong Rick Twee-Hee , Tan Eng Lee , Krishnan Prabha Unny , Ang Brenda Sze Peng , Lye David Chien , Chow Angela Li Ping , Teo Yik-Ying , Ng Oon Tek
Published: December 2013

We report the draft genome sequence of a New Delhi metallo-β-lactamase-1 (NDM-1)-positive
Escherichia coli
isolate obtained from a surgical patient. The assembled data indicate the presence of 3 multidrug resistance plasmids, 1 of which shares 100% identity with an NDM-1 plasmid isolated previously from a nearby hospital, suggesting possible local transmission.
Draft Genome Sequence of Lactobacillus crispatus EM-LC1, an Isolate with Antimicrobial Activity Cultured from an Elderly Subject
Authors: Power Susan E. , Harris Hugh M. B. , Bottacini Francesca , Ross R. Paul , O'Toole Paul W. , Fitzgerald Gerald F.
Published: December 2013

Here we report the 1.86-Mb draft genome sequence of
Lactobacillus crispatus
EM-LC1, a fecal isolate with antimicrobial activity. This genome sequence is expected to provide insights into the antimicrobial activity of
L. crispatus
and improve our knowledge of its potential probiotic traits.
Draft Genome Sequence of the Arsenite-Oxidizing Strain
Aliihoeflea
sp. 2WW, Isolated from Arsenic-Contaminated Groundwater
Authors: Cavalca Lucia , Corsini Anna , Andreoni Vincenza , Muyzer Gerard
Published: December 2013

Here, we report the draft genome sequence of the arsenite-oxidizing bacterium
Aliihoeflea
sp. strain 2WW, which consists of a 4.15-Mb chromosome and contains different genes that are involved in arsenic transformations.
Draft Genome Sequence of the Methanotrophic Gammaproteobacterium Methyloglobulus morosus DSM 22980 Strain KoM1
Authors: Poehlein Anja , Deutzmann Jörg S. , Daniel Rolf , Simeonova Diliana D.
Published: December 2013

Here, we report the draft genome sequence of the methanotrophic gammaproteobacterium
Methyloglobulus morosus
DSM 22980 strain KoM1, which is proposed to be the type species for the novel genus
Methyloglobulus
. The genome (4.143 Mb) consists of a single circular chromosome and harbors genes for 2-aminoethylphosphonate (ciliatine) biosynthesis.
Draft Genome Sequence of Klebsiella pneumoniae Strain KP-1
Authors: Lee Kai Wei Kelvin , Arumugam Krithika , Purbojati Rikky Wenang , Tay Qi Xiang Martin , Williams Rohan Benjamin Hugh , Kjelleberg Staffan , Rice Scott A.
Published: December 2013

Klebsiella pneumoniae
is ubiquitous in the environment and is a member of a three-species biofilm model. We compared the genome sequence of an environmental isolate,
K. pneumoniae
strain KP-1, to those of two clinical strains (NTUH-K2044 and MGH 78578). KP-1 possesses strain-specific prophage sequences that distinguish it from the clinical strains.
Draft Genome Sequence of the Obligate Halophilic
Bacillus
sp. Strain NSP22.2, Isolated from a Seasonal Salt Marsh of the Great Rann of Kutch, India
Authors: Dey Rinku , Pal Kamal Krishna , Sherathia Dharmesh , Vanpariya Sejal , Patel Ilaxi , Dalsania Trupti , Savsani Kinjal , Sukhadiya Bhoomika , Mandaliya Mona , Thomas Manesh , Ghorai Sucheta , Rupapara Rupal , Rawal Priya
Published: December 2013

Here, we report the 4.0-Mbp draft genome of an obligate halophile,
Bacillus
sp. strain NSP22.2, isolated from a seasonal salt marsh of the Great Rann of Kutch, India. To understand the mechanism(s) of obligate halophilism and to isolate the relevant gene(s), the genome of
Bacillus
sp. NSP22.2 was sequenced.
Implementation of an endoscopy safety checklist
Authors: Matharoo M , Thomas-Gibson S , Haycock A , Sevdalis N
Published: December 2013

Patient safety and quality improvement are increasingly prioritised across all areas of healthcare. Errors in endoscopy are common but often inconsequential and therefore go uncorrected. A series of minor errors, however, may culminate in a significant adverse event. This is unsurprising given the rising volume and complexity of cases coupled with shift working patterns. There is a growing body of evidence to suggest that surgical safety checklists can prevent errors and thus positively impact on patient morbidity and mortality. Consequently, surgical checklists are mandatory for all procedures. Many UK hospitals are mandating the use of similar checklists for endoscopy. There is no guidance on how best to implement endoscopy checklists nor any measure of their usefulness in endoscopy. This article outlines lessons learnt from innovating service delivery in our unit.
Beneficial effect of the bioflavonoid quercetin on cholecystokinin-induced mitochondrial dysfunction in isolated rat pancreatic acinar cells
Authors: Weber Heike , Jonas Ludwig , Wakileh Michael , Krüger Burkhard
Published: December 2013

The pathogenesis of acute pancreatitis (AP) is still poorly understood. Thus, a reliable pharmacological therapy is currently lacking. In recent years, an impairment of the energy metabolism of pancreatic acinar cells, caused by Ca2+-mediated depolarization of the inner mitochondrial membrane and a decreased ATP supply, has been implicated as an important pathological event. In this study, we investigated whether quercetin exerts protection against mitochondrial dysfunction. Following treatment with or without quercetin, rat pancreatic acinar cells were stimulated with supramaximal cholecystokinin-8 (CCK). CCK caused a decrease in the mitochondrial membrane potential (MMP) and ATP concentration, whereas the mitochondrial dehydrogenase activity was significantly increased. Quercetin treatment before CCK application exerted no protection on MMP but increased ATP to a normal level, leading to a continuous decrease in the dehydrogenase activity. The protective effect of quercetin on mitochondrial function was accompanied by a reduction in CCK-induced changes to the cell membrane. Concerning the molecular mechanism underlying the protective effect of quercetin, an increased AMP/ATP ratio suggests that the AMP-activated protein kinase system may be activated. In addition, quercetin strongly inhibited CCK-induced trypsin activity. The results indicate that the use of quercetin may be a therapeutic strategy for reducing the severity of AP.
Holding our breath in our modern world: will mitochondria keep the pace with climate changes?
Authors: Blier Pierre U. , Lemieux Hélène , Pichaud Nicolas
Published: December 2013

Changes in environmental temperature can pose considerable challenges to animals and shifts in thermal habitat have been shown to be a major force driving species’ adaptation. These adaptations have been the focus of major research efforts to determine the physiological or metabolic constraints related to temperature and to reveal the phenotypic characters that can or should adjust. Considering the current consensus on climate change, the focus of research will likely shift to questioning whether ectothermic organisms will be able to survive future modifications of their thermal niches. Organisms can adjust to temperature changes through physiological plasticity (e.g., acclimation), genetic adaptation, or via dispersal to more suitable thermal habitats. Thus, it is important to understand what genetic and phenotypic attributes—at the individual, population, and species levels—could improve survival success. These issues are particularly important for ectotherms, which are in thermal equilibrium with the surrounding environment. To start addressing these queries, we should consider what physiological or metabolic functions are responsible for the impact of temperature on organisms. Some recent developments indicate that mitochondria are key metabolic structures determining the thermal range that an organism can tolerate. The catalytic capacity of mitochondria is highly sensitive to thermal variation and therefore should partly dictate the temperature dependence of biological functions. Mitochondria contain a complex network of different enzymatic reaction pathways that interact synergistically. The precise regulation of both adenosine triphosphate (ATP) and reactive oxygen species (ROS) production depends on the integration of different enzymes and pathways. Here, we examine the temperature dependence of different parts of mitochondrial pathways and evaluate the evolutionary challenges that need to be overcome to ensure mitochondrial adaptations to new thermal environments.
THE D4FLAVOR SYMMETRY IN 3-3-1 MODEL WITH NEUTRAL LEPTONS
Authors: VIEN V. V. , LONG H. N.
Published: December 2013

We construct a D4flavor model based on SU(3)C⊗SU(3)L⊗U(1)Xgauge symmetry responsible for fermion masses and mixings. The neutrinos get small masses from antisextets which are in a singlet and a doublet under D4. If the D4symmetry is violated as perturbation by a Higgs triplet under SU(3)Land lying in [Formula: see text] of D4, the corresponding neutrino mass mixing matrix gets the most general form. In this case, the model can fit the experimental data in 2012 on neutrino masses and mixing. Our results show that the neutrino masses are naturally small and a little deviation from the tribimaximal neutrino mixing form can be realized. The quark masses and mixing matrix are also discussed. In the model under consideration, the CKM matrix can be different from the unit matrix. The scalar potential of the model is more simpler than those of the model based on S3and S4. Assignation of VEVs to antisextets leads to the mixing of the new gauge bosons and those in the Standard Model. The mixing in the charged gauge bosons as well as the neutral gauge boson is considered.
LANDAU CONFINING REPLICA MODEL FROM AN EXPLICITLY BREAKING OF A SU(3) GROUP WITHOUT AUXILIARY FIELDS
Authors: AMARAL M. M. , CAPRI M. A. L. , CHIFARELLI Y. E. , LEMES V. E. R.
Published: December 2013

We propose a mechanism displaying gluon confinement, as defined by the behavior of the propagators, in a model of SU(2) gauge fields. The model originates from an explicitly broken SU(3) gauge theory giving rise to a replica model composed of three mixed SU(2) groups. The mechanism consists in the usual SU(3) Yang–Mills theory in the Landau gauge, with a soft breaking term in such a way as to change the field propagation and group content at low energies. The relation of this soft mass term with the Gribov problem is presented and the link between soft terms and the scaling and decoupling solutions is discussed.
DEFORMED SPACE-TIME OF THE PIEZONUCLEAR EMISSIONS
Authors: CARDONE F. , CALBUCCI V. , ALBERTINI G.
Published: December 2013

In this paper, an experimental verification of the relationship between the deformed Minkowsky space-time and the piezonuclear emission has been obtained by testing several cylindrical steel bars cyclically loaded in a mechanical fatigue machine. During the compression cycles, α-particles have been both detected by a ZnS ( Ag ) scintillator and a Geiger counter. Taking into account the theory of the deformed special relativity, we report that the emission only occurs after a specific value of energy is overcome. This value is strictly related to the weak and strong nuclear interactions, which in turn define the regions of Minkowsky and non-Minkowsky space-time.
GENDER RECOGNITION FROM FACE IMAGES WITH DYADIC WAVELET TRANSFORM AND LOCAL BINARY PATTERN
Authors: HUSSAIN MUHAMMAD , ULLAH IHSAN , ABOALSAMH HATIM A. , MUHAMMAD GHULAM , BEBIS GEORGE , MIRZA ANWAR MAJID
Published: December 2013

Gender recognition from facial images plays an important role in biometric applications. Employing Dyadic wavelet Transform (DyWT) and Local Binary Pattern (LBP), we propose a new feature descriptor DyWT-LBP for gender recognition. DyWT is a multi-scale image transformation technique that decomposes an image into a number of sub-bands which separate the features at different scales. DyWT is a kind of translation invariant wavelet transform that has a better potential for detection than Discrete Wavelet Transform (DWT). On the other hand, LBP is a texture descriptor and is known to be the best for representing texture micro-patterns, which play a key role in the discrimination of different objects in an image. For DyWT, we used spline dyadic wavelets (SDW). There exist many types of SDW; we investigated a number of SDWs for finding the best SDW for gender recognition. The dimension of the feature space generated by DyWT-LBP descriptor becomes excessively high. To tackle this problem, we apply a feature subset selection (FSS) technique that not only reduces the number of features significantly but also improves the recognition accuracy. Through a large number of experiments performed on FERET and Multi-PIE databases, we report for DyWT-LBP descriptor the parameter settings, which result in the best accuracy. The proposed system outperforms the stat of the art gender recognition approaches; it achieved a recognition rate of 99.25% and 99.09% on FERET and Multi-PIE databases, respectively.
BEYOND 2020 — STRATEGIES AND COSTS FOR TRANSFORMING THE EUROPEAN ENERGY SYSTEM
Authors: KNOPF BRIGITTE , CHEN YEN-HENG HENRY , DE CIAN ENRICA , FÖRSTER HANNAH , KANUDIA AMIT , KARKATSOULI IOANNA , KEPPO ILKKA , KOLJONEN TIINA , SCHUMACHER KATJA , VAN VUUREN DETLEF P.
Published: December 2013

The Energy Modeling Forum 28 (EMF28) study systematically explores the energy system transition required to meet the European goal of reducing greenhouse gas (GHG) emissions by 80% by 2050. The 80% scenario is compared to a reference case that aims to achieve a 40% GHG reduction target. The paper investigates mitigation strategies beyond 2020 and the interplay between different decarbonization options. The models present different technology pathways for the decarbonization of Europe, but a common finding across the scenarios and models is the prominent role of energy efficiency and renewable energy sources. In particular, wind power and bioenergy increase considerably beyond current deployment levels. Up to 2030, the transformation strategies are similar across all models and for both levels of emission reduction. However, mitigation becomes more challenging after 2040. With some exceptions, our analysis agrees with the main findings of the "Energy Roadmap 2050" presented by the European Commission.
EUROPEAN ENERGY EFFICIENCY AND DECARBONIZATION STRATEGIES BEYOND 2030 — A SECTORAL MULTI-MODEL DECOMPOSITION
Authors: FÖRSTER HANNAH , SCHUMACHER KATJA , DE CIAN ENRICA , HÜBLER MICHAEL , KEPPO ILKKA , MIMA SILVANA , SANDS RONALD D.
Published: December 2013

Energy efficiency and decarbonization are important elements of climate change mitigation. We draw on European mitigation scenarios from the EMF28 modeling exercise to decompose economy-wide and sectoral emissions into their main components. We utilize the Logarithmic Mean Divisia Index (LMDI) to gain insights into five effects: affluence, energy intensity, carbon intensity, conversion efficiency, and structural change. Economy-wide analysis suggests that energy efficiency improvements (including end-use efficiency of production and structural change of the economy) determine emission reductions short to medium term while decarbonization becomes more important in the long term. Sectoral analysis suggests that electricity generation holds the largest potential for decarbonization. Mitigation in the transport and energy-intensive sectors is limited by technology availability, forcing output and energy inputs to decline to meet the given mitigation pathways. We conclude that energy efficiency improvements could bridge the time until carbon-free technologies mature, while their quick development remains essential.
Improving the performance of port range check for network packet filtering
Authors: Chang Yen-Jen , Lu Hsiang-Yu
Published: December 2013

This article introduces a high-performance packet filter design in which we propose the partial parallel range check (PPRC) technique for speeding up port range check. Unlike the conventional serial design that uses cascading cells to perform the serial check, PPRC divides the single path into several segments. All PPRC segments perform the range compare simultaneously, that is, parallel check, and then the results of each segment are serialized to generate the final check result. Besides theoretical analyses, we also use UMC 90nm CMOS process to implement the PPRC design and verify its effect on the check performance. Compared to state-of-the-art range check techniques, the results show that the PPRC design with the best configuration can improve check performance by 28%, at least. In addition, the PPRC design is more stable and energy efficient than related designs, even though it requires more transistors to implement the peripheral circuitry. The range of energy improvement achieved by the PPRC design is about 35%--70%.
CoMETC
Authors: Ayoub Raid , Nath Rajib , Rosing Tajana Simunic
Published: December 2013

We introduce a Coordinated Management of Energy, Thermal, and Cooling (CoMETC) technique to minimize cooling and memory energy of server machines. State-of-the-art solutions decouple the optimization of cooling energy costs and energy consumption of CPU and memory subsystems. This results in suboptimal solutions due to thermal dependencies between CPU and memory and the nonlinearity in energy costs of cooling. In contrast, we develop a unified solution that integrates energy, thermal, and cooling management for CPU and memory subsystems to maximize energy savings. CoMETC reduces the operational energy of the memory by clustering active memory pages to a subset of memory modules while accounting for thermal and cooling aspects. At the same time, CoMETC removes hotspots between and within the CPU sockets and reduces the effects of thermal coupling with memory in order to minimize cooling energy costs. We design CoMETC using a control-theoretic approach to guarantee meeting these objectives. We introduce a formal thermal and cooling model to be used for online decisions inside CoMETC. Our experimental results show that CoMETC achieves average cooling and memory energy savings of 58% compared to state-of-the-art techniques at a performance overhead of less than 0.3%.
Dynamic programming-based runtime thermal management (DPRTM)
Authors: Al-Dujaily Ra'ed , Dahir Nizar , Mak Terrence , Xia Fei , Yakovlev Alex
Published: December 2013

Complex thermal behavior inhibits the advancement of three-dimensional (3D) very-large-scale-integration (VLSI) system designs, as it could lead to ultra-high temperature hotspots and permanent silicon device damage. This article introduces a new runtime thermal management strategy to effectively diffuse and manage heat throughout 3D chip geometry for a better throughput performance in networks on chip (NoC). This strategy employs a dynamic programming-based runtime thermal management (DPRTM) policy to provide online thermal regulation. Reactive and proactive adaptive schemes are integrated to optimize the routing pathways depending on the critical temperature thresholds and traffic developments. Also, when the critical system thermal limit is violated, an urgent throttling will take place. The proposed DPRTM is rigorously evaluated through cycle-accurate simulations, and results show that the proposed approach outperforms conventional approaches in terms of computational efficiency and thermal stability. For example, the system throughput using the DPRTM approach can be improved by 33% when compared to other adaptive routing strategies for a given thermal constraint. Moreover, the DPRTM implementation presented in this article demonstrates that the hardware overhead is insignificant. This work opens a new avenue for exploring the on-chip adaptability and thermal regulation for future large-scale and 3D many-core integrations.
Near-optimal and scalable intrasignal in-place optimization for non-overlapping and irregular access schemes
Authors: Kritikakou Angeliki , Catthoor Francky , Kelefouras Vasilios , Goutis Costas
Published: December 2013

Storage-size management techniques aim to reduce the resources required to store elements and to concurrently provide efficient addressing during element accessing. Existing techniques are less appropriate for large iteration spaces with increased numbers of irregularly spread holes. They either have to approximate the accessed regions, leading to overestimation of the final resources, or they require prohibited exploration time to find the storage size. In this work, we present a near-optimal and scalable methodology for storage-size, intrasignal, in-place optimization, that is, to compute the minimum amount of resources required to store the elements of a group (array), for irregular complex access schemes in the target domain of non-overlapping store and load accesses.
Low-energy volatile STT-RAM cache design using cache-coherence-enabled adaptive refresh
Authors: Li Jianhua , Shi Liang , Li Qingan , Xue Chun Jason , Chen Yiran , Xu Yinlong , Wang Wei
Published: December 2013

Spin-Torque Transfer RAM (STT-RAM) is a promising candidate for SRAM replacement because of its excellent features, such as fast read access, high density, low leakage power, and CMOS technology compatibility. However, wide adoption of STT-RAM as cache memories is impeded by its long write latency and high write power. Recent work proposed improving the write performance through relaxing the retention time of STT-RAM cells. The resultant
volatile
STT-RAM needs to be periodically refreshed to prevent data loss. When volatile STT-RAM is applied as the last-level cache (LLC) in chip multiprocessor (CMP) systems, frequent refresh operations could dissipate significant extra energy. In addition, refresh operations could severely conflict with normal read/write operations to degrade overall system performance. Therefore, minimizing the performance impact caused by refresh operations is crucial for the adoption of volatile STT-RAM.

In this article, we propose Cache-Coherence-Enabled Adaptive Refresh (CCear) to minimize the number of refresh operations for volatile STT-RAM, adopted as the LLC for CMP systems. Specifically, CCear interacts with cache coherence protocol and cache management policy to minimize the number of refresh operations on volatile STT-RAM caches. Full-system simulation results show that CCear performs close to an ideal refresh policy with low overhead. Compared with state-of-the-art refresh policies, CCear simultaneously improves the system performance and reduces the energy consumption. Moreover, the performance of CCear could be further enhanced using small filter caches to accommodate the not-refreshed private STT-RAM blocks.
Optimal common-centroid-based unit capacitor placements for yield enhancement of switched-capacitor circuits
Authors: Huang Chien-Chih , Wey Chin-Long , Chen Jwu-E , Luo Pei-Wen
Published: December 2013

Yield is defined as the probability that the circuit under consideration meets with the design specification within the tolerance. Placement with higher correlation coefficients has fewer mismatches and lower variation of capacitor ratio, thus achieving higher yield performance. This study presents a new optimization criterion that quickly determines if the placement is optimal. The optimization criterion leads to the development of the concepts of C-entries and partitioned subarrays which can significantly reduce the searching space for finding the optimal/near-optimal placements on a sufficiently large array size.
Performance bound analysis of analog circuits in frequency- and time-domain considering process variations
Authors: Liu Xue-Xin , Tan Sheldon X.-D. , Palma-Rodriguez Adolfo Adair , Tlelo-Cuautle Esteban , Shi Guoyong
Published: December 2013

In this article, we propose a new performance bound analysis of analog circuits considering process variations. We model the variations of component values as intervals measured from tested chips and manufacture processes. The new method first applies a graph-based analysis approach to generate the symbolic transfer function of a linear(ized) analog circuit. Then the frequency response bounds (maximum and minimum) are obtained by performing nonlinear constrained optimization in which magnitude or phase of the transfer function is the objective function to be optimized subject to the ranges of process variational parameters. The response bounds given by the optimization-based method are very accurate and do not have the over-conservativeness issues of existing methods. Based on the frequency-domain bounds, we further develop a method to calculate the time-domain response bounds for any arbitrary input stimulus. Experimental results from several analog benchmark circuits show that the proposed method gives the correct bounds verified by Monte Carlo analysis while it delivers one order of magnitude speedup over Monte Carlo for both frequency-domain and time-domain bound analyses. We also show analog circuit yield analysis as an application of the frequency-domain variational bound analysis.
Application-aware adaptive cache architecture for power-sensitive mobile processors
Authors: Bournoutian Garo , Orailoglu Alex
Published: December 2013

Today, mobile smartphones are expected to be able to run the same complex, algorithm-heavy, memory-intensive applications that were originally designed and coded for general-purpose processors. All the while, it is also expected that these mobile processors be power-conscientious as well as of minimal area impact. These devices pose unique usage demands of ultra-portability but also demand an always-on, continuous data access paradigm. As a result, this dichotomy of continuous execution versus long battery life poses a difficult challenge. This article explores a novel approach to mitigating mobile processor power consumption while abating any significant degradation in execution speed. The concept relies on efficiently leveraging both compile-time and runtime application memory behavior to intelligently target adjustments in the cache to significantly reduce overall processor power, taking into account both the dynamic and leakage power footprint of the cache subsystem. The simulation results show a significant reduction in power consumption of approximately 13% to 29%, while only incurring a nominal increase in execution time and area.