Optimizing sorting algorithms for the Cell Broadband Engine

The quest for higher performance in computationally intensive tasks is and will always be an ongoing effort. General purpose processors (GPP) have not been sufficient for many of these tasks which has led to research focused towards computing on specialty processors and graphics processing units (GPU). While GPU provide sufficient speedups for some tasks, other specialty processors may be better suited, more economical, or more efficient for different types of tasks. Sorting is an important task in many applications and can be computationally intensive when dealing with large data sets. One such specialty processor that has proven to be a viable solution for sorting is the Cell Broadband Engine (CBE). The CBE is being used as the main platform for this thesis since there are already applications for it that require sorting software. The Cell processor is a general purpose processor that combines one master PowerPC core with eight other vector processors connected via a high bandwidth interconnect bus. The user must explicitly manage the communication, scheduling, and load-balancing between the vector processors and the PowerPC processor to achieve the highest efficiency. By optimizing the sorting algorithms for the vector processors, large speedups can be achieved because multiple operations occur simultaneously. Optimized sorting software is often sought when sorting is not the main purpose of the application. This keeps overheads low so that the performance gains can be realized from the actual code that is to be optimized on specialty processors. Often having sorted datasets enable algorithms to run faster and are more predictably. The motivation behind this thesis is that there is currently no standard library of sorting algorithms that have been optimized for the CBE. Lack of standard libraries makes writing code for the CBE difficult. Results from previous works have also not been sufficient in providing specific measurements of sorting performance. This thesis will explore the development and analysis of a variety of optimized parallel sorting algorithms written for the Cell processor. This thesis will focus on the sorting of both individual elements within vectors as well as sorting entire vectors within arrays. The sorting algorithms, written in C++, that will be optimized and analyzed include, but are not limited to bitonic sort, heap sort, merge sort, and quick sort. A communication management framework will also be created as a main focus of this thesis in order to better understand the architecture of the processor

Cost-Effectiveness Evaluation of Swiss Agri-Environmental Measures on Sector Level

Abstract This paper focuses on non-linear programming models and their suitability for ex-ante evaluations of agri-environmental policies on sector level. An approach is presented to compare organic farming payments as a multi-objective policy, with other, more targeted agri-environmental policies in Switzerland. The Swiss version of the comparative static sector-consistent farm group model FARMIS is able to group the sector’s farms into organic and non-organic farms and optimise them separately. CH-FARMIS is expanded with three modules particularly for this study: a) allowing for the simulation of uptake; b) integrating life cycle assessment data for energy use, eutrophication and biodiversity; and c) estimating the policy and farm-group-specific public expenditure, including transaction costs. This paper illustrates the functions of the model, shows preliminary energy use calculations for the German Agricultural Sector and discusses the advantages and limitations of the approach

Indoor air quality in California homes with code-required mechanical ventilation.

Data were collected in 70 detached houses built in 2011-2017 in compliance with the mechanical ventilation requirements of California's building energy efficiency standards. Each home was monitored for a 1-week period with windows closed and the central mechanical ventilation system operating. Pollutant measurements included time-resolved fine particulate matter (PM2.5 ) indoors and outdoors and formaldehyde and carbon dioxide (CO2 ) indoors. Time-integrated measurements were made for formaldehyde, NO2 , and nitrogen oxides (NOX ) indoors and outdoors. Operation of the cooktop, range hood, and other exhaust fans was continuously recorded during the monitoring period. Onetime diagnostic measurements included mechanical airflows and envelope and duct system air leakage. All homes met or were very close to meeting the ventilation requirements. On average, the dwelling unit ventilation fan moved 50% more airflow than the minimum requirement. Pollutant concentrations were similar to or lower than those reported in a 2006-2007 study of California new homes built in 2002-2005. Mean and median indoor concentrations were lower by 44% and 38% for formaldehyde and 44% and 54% for PM2.5 . Ventilation fans were operating in only 26% of homes when first visited, and the control switches in many homes did not have informative labels as required by building standards

Analyzing technology acceptance and perception of privacy in ambient assisted living for using sensor-based technologies

People increasingly use various technologies that enable them to ease their everyday lives in different areas. Not only wearable devices are gaining ground, but also sensor-based ambient devices and systems are increasingly perceived as beneficial in supporting users. Especially older and/or frail persons can benefit from the so-called lifelogging technologies assisting the users in different activities and supporting their mobility and autonomy. This paper empirically investigates users' technology acceptance and privacy perceptions related to sensor-based applications implemented in private environments (i.e., passive infrared sensors for presence detection, humidity and temperature sensors for ambient monitoring, magnetic sensors for user-furniture interaction). For this purpose, we designed an online survey entitled "Acceptance and privacy perceptions of sensor-based lifelogging technologies"and collected data from N = 312 German adults. In terms of user acceptance, statistical analyses revealed that participants strongly agree on the benefits of such sensorbased ambient technologies, also perceiving these as useful and easy to use. Nevertheless, their intention to use the sensor-based applications was still rather limited. The evaluation of privacy perceptions showed that participants highly value their privacy and hence require a high degree of protection for their personal data. The potential users assessed the collection of data especially in the most intimate spaces of domestic environments, such as bathrooms and bedrooms, as critical. On the other hand, participants were also willing to provide complete data transparency in case of an acute risk to their health. Our results suggest that users' perceptions of personal privacy largely affect the acceptance and successful adoption of sensor-based lifelogging in home environments

Structural Biology of Peanut Allergens

Peanuts are a cause of one of the most common food allergies. Allergy to peanuts not only affects a significant fraction of the population, but it is relatively often associated with strong reactions in sensitized individuals. Peanut and tree nut allergies, which start in childhood are often persistent and continue through life, as opposed to other food allergies that resolve with age. Cherefore, peanut allergens are one of the most intensively studied food allergens. In this review we focus on the structural studies of peanut allergens. Despite the fact that these allergens are attracting a lot of interest and several of them have had their structures experimentally determined, still some molecular properties of peanut allergens are not well understood. Peanut allergens like other allergens belong to just a few protein families. Allergens from the cupin superfamily (Ara h 1 and Ara h 3), 2S albumins (Arah 2 and Ara h 6), Ara h 8 (pathogenesis related class-10 protein) and Ara h 5 (profilin) are relatively well characterized in terms of their 3D structures. However some peanut allergens like Ara h 7 (2S albumin), Ara h 9 (nonspecific lipid-transfer protein), and especially oleosins (Ara h 10 and Ara h 11) and defensins (Ara h 12 and Ara h 13), still are waiting for such characterization

Indications for the Nonexistence of Three-Neutron Resonances near the Physical Region

The pending question of the existence of three-neutron resonances near the physical energy region is reconsidered. Finite rank neutron-neutron forces are used in Faddeev equations, which are analytically continued into the unphysical energy sheet below the positive real energy axis. The trajectories of the three-neutron S-matrix poles in the states of total angular momenta and parity J^\pi=1/2 +- and J^\pi= 3/2 +- are traced out as a function of artificial enhancement factors of the neutron-neutron forces. The final positions of the S-matrix poles removing the artificial factors are found in all cases to be far away from the positive real energy axis, which provides a strong indication for the nonexistence of nearby three-neutron resonances. The pole trajectories close to the threshold E=0 are also predicted out of auxiliary generated three-neutron bound state energies using the Pad\'e method and agree very well with the directly calculated ones.Comment: 20 pages, 7 Postscript figures, fig.1 is corrected, uses relax.st

Photothermal infrared thermography applied to the identification of thin layer thermophysical properties

Abstract: The aim of the present work is the thermal non-destructive characterisation of layers at the surface of metals. The sample is sinusoidally heated by means of an argon ion laser and a focal plane array infrared camera (CEDIP IRC 320-4 LW) is used to measure the temperature variations at the surface of the layer. A numerical lock-in procedure allows the detection of very weak temperature variations at the surface of the sample, down to a few mK when working from the acquisition of hundreds of images, yielding amplitude and absolute phase maps for modulation frequencies ranging from 0.1 Hz to 1000 Hz. An inverse procedure uses the Gauss-Newton parameter estimation method, in order to identify the thermal conductivity and the optical absorption coefficient of the layer. Confidence intervals on the parameters can also be estimated by the inverse procedure. More particular attention is devoted to the study of the sensitivity coefficients, as functions of the frequency range and of the radial range along the profiles, in order to optimise the identification procedure

Use of CRISTA mesopause region temperatures for the intercalibration of gound-based instruments

Most available ground-based (GB) techniques for measuring temperatures in the upper mesosphere to lower thermosphere (or mesopause region) have systematic errors that are comparable to those of orbiting instruments. Determining these unknown biasses would normally require colocated observations that are only seldom feasible. Satellite measurements can be used as a ‘‘transfer standard’’ between GB observations that are not colocated. In this context, even with a reproducible or known bias in the satellite data, the comparison is still meaningful. Since Cryogenic Infrared Spectrometers and Telescopes for the Atmosphere (CRISTA) temperatures cover the mesopause region with very good accuracy (statistical errors do not exceed 1.5 K and systematic uncertainties range from about 3–7.5 K), they are quite suitable for this purpose. Because of the nearly constant precision over the height range of interest, also rotational temperatures of airglow emissions from different altitudes like the OH and O2 bands (or the OI 558 nm line) can be successfully compared with each other. In spite of the limited number of overpasses during the relatively short CRISTA missions, the feasibility of such an intercalibration is demonstrated for widely separated GB sites. Here, the results obtained for GB measurements at eight different sites, using CRISTA-1 and CRISTA-2 data, are presented. For OH temperatures, the standard deviation between the different instruments is only 5.4 K, confirming previous estimates.Fil: Scheer, Jurgen. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Reisin, Esteban Rodolfo. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Gusev, O. A.. University of Wuppertal; AlemaniaFil: French, W. J. R.. Australian Antarctic Division; AustraliaFil: Hernandez, G.. University of Washington; Estados UnidosFil: Huppi, R.. State University Of Utah; Estados UnidosFil: Ammosov, P.. Institute of Cosmophysical Research and Aeronomy; RusiaFil: Gavrilyeva, G. A.. Institute of Cosmophysical Research and Aeronomy; RusiaFil: Offermann, D.. University of Wuppertal; Alemani