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In this paper we present some experiments on the MySQL database server. The objective of the experiments was to investigate the high load dynamics for varying relation sizes and requests. We show that the dynamics for SELECT (read) requests can be modeled as a modified M/M/1 system, whereas, the dynamics for UPDATE (write) are completely different. Our results can be used for designing control and

For multi-vehicle complex traffic scenarios in shared spaces such as intelligent intersections, safe coordination and trajectory planning is challenging due to computational complexity. To meet this challenge, we introduce a computationally efficient method for generating collision-free trajectories along predefined vehicle paths. We reformulate a constrained minimum-time trajectory planning probl

This paper describes a named entity recognition (NER) system for short text messages (SMS) running on a mobile platform. Most NER systems deal with text that is structured, formal, well written, with a good grammatical structure, and few spelling errors. SMS text messages lack these qualities and have instead a short-handed and mixed language studded with emoticons, which makes NER a challenge on

We have implemented a compiler for key parts of Modelica, an object-oriented language supporting equation-based modeling and simulation of complex physical systems. The compiler is extensible, to support experiments with emerging tools for physical models. To achieve extensibility, the implementation is done declaratively in JastAdd, a metacompilation system supporting modern attribute grammar mec

Combining attribute grammars with object-oriented programming supports a new kind of declarative programming, allowing compilers to be built in a highly extensible manner. By leveraging a base compiler, extended languages can be supported at a relatively low cost. Recent work shows the applicability of the technique to general-purpose programming languages like Java. In this article, we illustrate

Today’s cloud data center infrastructures are not even near being able to cope with the enormous and rapidly varying capacity demands that will be reality in a near future. So far, very little is understood about how to transform today’s data centers (being large, power-hungry facilities, and operated through heroic efforts by numerous administrators) into a self-managed, dynamic, and dependable i

Popular Abstract in SwedishMed tonsättaren och musikkritikern Moses Pergament (1893-1977) som biografiskt lod har syftet med denna studie varit att blottlägga och analysera föreställningar om "juden", modernism, nationalism och "ras" i det svenska samhället. Pergament föddes i Helsingfors och växte upp i ett svenskspråkigt judiskt-ortodoxt hem. Han kom till Sverige 1916 och blev svensk medborgare With the composer and music critic Moses Pergament (1893-1977) as a biographical prism, the purpose of this study has been to uncover ideas in Swedish society about nationalism, "the Jew", modernism and "race". Pergament was born in Helsinki, Finland, and grew up in a Swedish-speaking, Jewish orthodox home. He came to Sweden in 1916 and became a Swedish citizen in 1919. Along with his composing, P

Response time is a measure of quality of service in com- puter systems. Estimation techniques, suitable for support systems for mobile phone systems, are explored. These sys- tems are complex queueing systems with large databases. The trac generated by users and system adminstrators changes rapidly, some loads can be measured other cannot. Attempts to capture all details give models that are not s

Resource-optimization of the infrastructure for service oriented applications require accurate performance models. In this paper we investigate the performance dynamics of a MySQL/InnoDB database server with write-heavy workload. The main objective of our investigation was to understand the system dynamics due to the buffering of disk operations that occurs in database servers with write-heavy wor

The diversity of different life-forms, their conquest of virtually all available habitats, and their seemingly limitless ability to adapt to new ecological challenges show that structural and physiological specializations of a few basic building plans uniquely match plants and animals to the specific lives they lead.

This paper presents a receiver architecture for intraband dual-carrier reception as specified for the upcoming releases of 3GPP WCDMA and LTE standards. It is based on a time-discrete harmonic rejection complex-IF mixer to limit the bandwidth requirements on the ADCs to that of a single carrier. The mixer has been designed and fabricated together with a 3rd order continuous-time (CT) delta-sigma A

Reconstruction of movement control properties of the brain could result in many potential advantages for application in robotics. However, a hampering factor so far has been the lack of knowledge of the structure and function of brain circuitry in vivo during movement control. Much more detailed information has recently become available for the area of the cerebellum that controls arm–hand movemen

Popular Abstract in English There is a growing prevalence of disorders associated to the metabolic syndrome globally. To reverse this trend lifestyle changes are required. Among dietary factors, dietary fibre that is associated with several health benefits plays an interesting role. Barley is highly unutilized as human food, and it contains high amounts of dietary fibre. The composition of the barBarley is one of the most important crops in the world. Although it is mainly used as the raw material for the production of beer and animal feed, it has recently attracted interest from nutritionists and consumers, due to its high content of dietary fibre, especially β-glucan, and its relation to various positive health effects. The proposed mechanisms behind the health effects are the formation

Competition is an integrated part of most civilizations, from sports to education. Often competition arise whether or not it was intended and higher education is no exception from this. Should teachers acknowledge this and try to introduce competition as a part of the course or should they try to prevent competition, even spontaneously arisen competition? In this paper an overview of effects of co

In this chapter a technology for the enhancement of video data obtained at low light levels is presented. The method was inspired by the way in which nocturnal animals adaptively sum intensities, spatially and temporally, to improve vision at night. Due to the low photon count under these conditions the visual input is dark and unreliable, which leads to noisy low contrast images. The noise become

This article describes results of the work on knowledge representation techniques chosen for use in the European project SIARAS (Skill-Based Inspection and Assembly for Reconfigurable Automation Systems). Its goal was to create intelligent support system for reconfiguration and adaptation of robot-based manufacturing cells. Declarative knowledge is represented first of all in an ontology expressed

We present a comparative exploratory analysis of two proximity networks of mobile phone users, the Proximates network and the Reality Mining network. Data for both networks were collected from mobile phones carried by two groups of users. Periodic Bluetooth scans were performed to detect the proximity of other mobile phones. The Reality Mining project took place in 2004-2005 at MIT, while Proximat