Dynamic diffracting trees

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997.Includes bibliographical references (p. 109-111).by Giovanni M. Della-Libera.M.Eng

Contention Adapting Search Trees

Abstract-With multicores being ubiquitous, concurrent data structures are becoming increasingly important. This paper proposes a novel approach to concurrent data structure design where the data structure collects statistics about contention and adapts dynamically according to this statistics. We use this approach to create a contention adapting binary search tree (CA tree) that can be used to implement concurrent ordered sets and maps. Our experimental evaluation shows that CA trees scale similar to recently proposed algorithms on a big multicore machine on various scenarios with a larger set size, and outperform the same data structures in more contended scenarios and in sequential performance. We also show that CA trees are well suited for optimization with hardware lock elision. In short, we propose a practically useful and easy to implement and show correct concurrent search tree that naturally adapts to the level of contention. I. INTRODUCTION With multicores being widespread, the need for efficient concurrent data structures has increased. In this paper we propose a novel adaptive technique for creating concurrent data structures. Our technique collects statistics about contention in locks and does local adaptations dynamically to reduce the contention or to optimize for low contention. This is the first contribution of this paper. Previous research on adapting to the level of contention has focused on objects where access cannot be easily distibuted, such as locks We demonstrate the benefits of our contention adapting technique by describing and evaluating a data structure for concurrent ordered sets or maps. We call this data structure contention adapting search tree or CA tree for short. The design of CA trees is the second contribution of this paper. Curren

Microsystems technology: objectives

This contribution focuses on the objectives of microsystems technology (MST). The reason for this is two fold. First of all, it should explain what MST actually is. This question is often posed and a simple answer is lacking, as a consequence of the diversity of subjects that are perceived as MST. The second reason is that a map of the somewhat chaotic field of MST is needed to identify sub-territories, for which standardization in terms of system modules an interconnections is feasible. To define the objectives a pragmatic approach has been followed. From the literature a selection of topics has been chosen and collected that are perceived as belonging to the field of MST by a large community of workers in the field (more than 250 references). In this way an overview has been created with `applications¿ and `generic issues¿ as the main characteristics

Enfleshing Entanglements of Space, Time, and Matter Through Diffractive Artistic Processes: Conversations with my Late Great Nana Through Her Archival Journals.

Within this thesis I share the story of my entangled relationalities with my great nana, Dorothy, who passed away when I was three years old. Dorothy was a brilliant artist, and I grew up surrounded by her paintings that hang on the walls of my family home. Looking through these painted portals into Dorothy’s imagination throughout my life has greatly inspired my journey into becoming an artist, researcher, and teacher. Twenty-three years after her death, shortly before I began my graduate studies in art education, my family unexpectedly discovered a box of Dorothy’s archival journals, sketches, and photographs, within which she has documented her own various artistic processes. Within this inquiry, I explore Dorothy’s archival artistic processes through creating my own, expanding upon her past moments within my present pedagogic experiences, collectively weaving together a new story that defies boundaries, and enfleshes entanglements of space, time, and matter. As such, this research unfolds from the middle, through layers, rather than chapters, where past and future meet in the presence of becoming. This thesis both explores artistic processes and is composed as an artistic process in itself, rippling outwards from the present moment through various diffractive dimensions (Barad, 2007). Waves and undercurrents of meaning become increasingly dynamic as I investigate the pedagogic value of process through mapping an artistic process directly into the form and content of my inquiry

Models for energy consumption of data structures and algorithms

EXCESS deliverable D2.1. More information at http://www.excess-project.eu/This deliverable reports our early energy models for data structures and algorithms based on both micro-benchmarks and concurrent algorithms. It reports the early results of Task 2.1 on investigating and modeling the trade-off between energy and performance in concurrent data structures and algorithms, which forms the basis for the whole work package 2 (WP2). The work has been conducted on the two main EXCESS platforms: (1) Intel platform with recent Intel multi-core CPUs and (2) Movidius embedded platform

White-box methodologies, programming abstractions and libraries

EXCESS deliverable D2.2. More information at http://www.excess-project.eu/This deliverable reports the results of white-box methodologies and early results ofthe first prototype of libraries and programming abstractions as available by projectmonth 18 by Work Package 2 (WP2). It reports i) the latest results of Task 2.2on white-box methodologies, programming abstractions and libraries for developingenergy-efficient data structures and algorithms and ii) the improved results of Task2.1 on investigating and modeling the trade-off between energy and performance ofconcurrent data structures and algorithms. The work has been conducted on two mainEXCESS platforms: Intel platforms with recent Intel multicore CPUs and MovidiusMyriad1 platform

Structural investigations with high pressure techniques and multicomponent systems

This thesis illustrates the use of high pressure crystallography techniques for the discovery and investigation of solid-state forms and probes the relationship between molecular structure and compression of both single and multicomponent systems. As well as investigating a data-driven approach to directing experimental co-crystallisation attempts.;Single crystal X-ray diffraction techniques are a highlight in all areas of this study, as well as computational approaches which were used in the evaluation of the interactions of small molecule systems. Data-mining of the Cambridge Structural Database made the comparison of the compression studies richer.;The pharmaceutical co-crystal, indomethacin and saccharin was analysed with respect to increasing pressure. The system is an example of a homomolecular synthon co-crystal allowing investigation of the component dimers free of strong interaction with surrounding molecules. The ambient pressure structure remains stable but investigation showed that the saccharin dimer sits in a pocket made by indomethacin allowing the dimer to lie further apart than in the pure compound.;To follow, a structural compression study of the single component saccharin using synchrotron radiation lead to the structural characterisation of the first new polymorph of saccharin. The hydrogen bonding pattern of the new phase remains consistent however Pixel calculations revealed that the biggest difference in packing arises due to the reduction of an interlayer distance.;To further explore multicomponent systems, two stoichiometric ratios of benzoic acid and isonicotinamide (2:1 & 1:1) were investigated. The rate of compression in these systems are almost identical despite the different molecular packing in each of the stoichiometric ratios. Through the investigation of materials in these initial chapters, the rate of compression in particular supramolecular synthons, e.g. amide-dimers, is demonstrated to be consistent despite the difference in the molecular make-up of the materials under study and their packing arrangements.;Lastly, a data-driven approach was applied in directing the discovery of a new solid-state entity. Following previous failed attempts, machine learning was employed to direct experimental co-crystallisations which led to a new co-crystal of Artemisinin and 1-Napthol. Pixel calculations revealed that the largest contribution to crystal stabilisation comes from dispersion energy and enabled the identification of dominant intermolecular interactions in the crystal structures.This thesis illustrates the use of high pressure crystallography techniques for the discovery and investigation of solid-state forms and probes the relationship between molecular structure and compression of both single and multicomponent systems. As well as investigating a data-driven approach to directing experimental co-crystallisation attempts.;Single crystal X-ray diffraction techniques are a highlight in all areas of this study, as well as computational approaches which were used in the evaluation of the interactions of small molecule systems. Data-mining of the Cambridge Structural Database made the comparison of the compression studies richer.;The pharmaceutical co-crystal, indomethacin and saccharin was analysed with respect to increasing pressure. The system is an example of a homomolecular synthon co-crystal allowing investigation of the component dimers free of strong interaction with surrounding molecules. The ambient pressure structure remains stable but investigation showed that the saccharin dimer sits in a pocket made by indomethacin allowing the dimer to lie further apart than in the pure compound.;To follow, a structural compression study of the single component saccharin using synchrotron radiation lead to the structural characterisation of the first new polymorph of saccharin. The hydrogen bonding pattern of the new phase remains consistent however Pixel calculations revealed that the biggest difference in packing arises due to the reduction of an interlayer distance.;To further explore multicomponent systems, two stoichiometric ratios of benzoic acid and isonicotinamide (2:1 & 1:1) were investigated. The rate of compression in these systems are almost identical despite the different molecular packing in each of the stoichiometric ratios. Through the investigation of materials in these initial chapters, the rate of compression in particular supramolecular synthons, e.g. amide-dimers, is demonstrated to be consistent despite the difference in the molecular make-up of the materials under study and their packing arrangements.;Lastly, a data-driven approach was applied in directing the discovery of a new solid-state entity. Following previous failed attempts, machine learning was employed to direct experimental co-crystallisations which led to a new co-crystal of Artemisinin and 1-Napthol. Pixel calculations revealed that the largest contribution to crystal stabilisation comes from dispersion energy and enabled the identification of dominant intermolecular interactions in the crystal structures