The impact of balancing on problem hardness in a highly structured domain

Random problem distributions have played a key role in the study and design of algorithms for constraint satisfaction and Boolean satisfiability, as well as in ourunderstanding of problem hardness, beyond standard worst-case complexity. We consider random problem distributions from a highly structured problem domain that generalizes the Quasigroup Completion problem (QCP) and Quasigroup with Holes (QWH), a widely used domain that captures the structure underlying a range of real-world applications. Our problem domain is also a generalization of the well-known Sudoku puz- zle: we consider Sudoku instances of arbitrary order, with the additional generalization that the block regions can have rectangular shape, in addition to the standard square shape. We evaluate the computational hardness of Generalized Sudoku instances, for different parameter settings. Our experimental hardness results show that we can generate instances that are considerably harder than QCP/QWH instances of the same size. More interestingly, we show the impact of different balancing strategies on problem hardness. We also provide insights into backbone variables in Generalized Sudoku instances and how they correlate to problem hardness.

Customer Research on a Group of European Book Publishers: Trends, Modes of Operation and Decision-Making Processes

Työn päätarkoitus oli tuottaa Stora Enson käyttöön tietoa kirjakustantajista, yhdestä yrityksen asiakassegmentistä. Yritys oli kiinnostunut useista asioista, jotka koskivat asiakkaita ja heidän mielipiteitään. Tarkoitus on, että Stora Enso voi käyttää tutkimuksella koottua tietoa oman toimintansa suunnittelun tukena. Kerätty sekundääritieto esittelee eurooppalaisen kirjakustantamisen nykytilaa ja tulevaisuutta sekä teorioita, jotka tukevat tutkittuja aihealueita. Primääritieto kerättiin henkilökohtaisilla haastatteluilla. Otanta koostui kymmenestä kirjakustantajasta, jotka toimivat Suomessa sekä Stora Enson päämarkkina-alueilla. Tutkimus tarjoaa päivitetyn kuvauksen kirjakustantamisesta. Haastateltavien mielipiteet alan trendeistä olivat yhteneviä yleisen mielipiteen kanssa, eikä suuria mielipide-eroavaisuuksia havaittu. Kustantajien toimintatapoja ja päätöksentekoprosesseja voidaan kuvata monimutkaisiksi, koska useat asiat vaikuttavat kirjan syntyyn ja paperin ostoprosessiin. Lisäksi tutkimus esittelee haastateltavien mielipiteitä paperin merkityksestä heidän liiketoiminnassaan.

Paleontological research on late Triassic radiolarians from Oman and Sicily

Les radiolaires sont des unicellulaires planctoniques qui peuplent nos océans depuis plus de 500 millions d'années. Ces microorganismes développent un squelette en silice ayant des géométries extrêmement diversifiées et sophistiqués qui varient rapidement à l'échelle géologique et permettent de construire des échelles biochronologiques basées sur les différents assemblages qui se succèdent dans le temps. On retrouve ces organismes à l'état fossile dans les roches ma¬rines siliceuse desquelles on peut les extraire avec de l'acide. Des échantillons provenant du sultanat d'Oman et de Sicile ont été étudiés afin de mieux com¬prendre les relations de parenté entre les groupes et de comparer les faunes avec celles du même âge venant de Colombie britannique, du Japon et de Turquie, qui sont représentatives de divers domaines océaniques de l'époque. Certains radiolaires possèdent un anneau autour de leur coque centrale sphérique et ont ainsi été baptisés Saturnalides. Il y a 215 millions d'années, au Norien moyen, ce groupe se diversifie soudainement et donne naissance à une multitude d'espèces qui évoluent rapidement ce qui a permis d'établir des subdivisions temporelles supplémentaires et d'affiner les zonations exis¬tantes. L'étude détaillée de formes intermédiaires entre les espèces a permis d'établir de nouveaux liens de parenté et de considérer le genre Praehexasaturnalis comme l'ancêtre probable de nom¬breuses formes dans le Norien moyen et supérieur. Grâce à l'étude comparative des espèces de Saturnalidae allant du Mésozoïque au Cénozoïque, un certain type d'asymétrie de l'anneau a pu être identifiée comme étant propre à cette famille et plus précisément liée à la disposition de la coque la plus interne (microsphère). Deux nouveaux genres, Blechschmidtia et Tjerkium, s'inscrivent dans une lignée parallèle au Saturnalidae. Cette lignée met en évidence la formation au cours du temps d'un anneau à partir de la fusion de deux épines opposées. -- Late Triassic marine deposits of the Tethyan realm have been investigated in the Sultanate of Oman and in Sicily in order to contribute to the knowledge of radiolarian taxonomy and bio- stratigraphy of this key period preceding the Triassic-Jurassic boundary. In the middle Norian, the saturnalid radiolarians display intense diversification. This blooming of fast evolving spe¬cies has been used to establish a new zonation based on evolutionary successions that refine the existing zonal schemes. One new genus and 16 new species are described. The chronologic distribution of 172 species belonging to 72 genera is established from five sections in the Umar and Al Aridh units of the Hawasina Basin. Many Late Triassic saturnalid species are interpreted to originate from the genus Praehexasaturnalis Kozur & Mostler, which shows strong morpho¬logical diversification patterns. Detailed comparative studies of different types of asymmetric ring morphologies of Mesozoic to Cainozoic saturnalid species permitted to relate the origin of the asymmetry to the disposition of the initial skeletal structure and to gain new insight on the internal and external geometrical transformations of this group trough time and how the emergence of new families is induced by environmental stress. RÉSUMÉ Les formations marines du Trias supérieur du domaine téthysien ont été étudiées dans le Sultanat d'Oman et en Sicile afin de contribuer à la connaissance et au développement de la taxonomie et de la biostratigraphie des radiolaires de cette période clé qui précède la crise de la limite Trias-Jurassique. Au Norien moyen, les radiolaires Saturnalides montrent une intense diversi¬fication. Ce véritable "bloom" d'espèces qui évoluent rapidement a été utilisé pour l'établisse¬ment d'une nouvelle zonation basée sur les successions évolutives de ce groupe qui permettent d'affiner les subdivisions biochronologiques existantes. Un nouveau genre et seize nouvelles espèces sont décrits. La distribution stratigraphique de 172 espèces appartenant à 72 genres est établie pour 5 sections dans les unités d'Umar et d'Al Aridh du bassin de Hawasina. Un essai d'établissement d'une phylogénèse des Saturnalidae du Trias supérieur mène à proposer que le genre Praehexasaturnalis Kozur & Mostler est l'ancêtre de beaucoup d'espèces de Saturnalidae du Trias supérieur. L'étude comparative détaillée des différents types d'asymétrie de l'anneau chez les Saturnali¬dae du Mésozoïque au Cénozoïque a permis de lier l'origine de ce phénomène à la disposition de la structure initiale de leur squelette et par ce fait d'avoir une meilleure compréhension des transformations géométriques internes et externes subies par ce groupe au cours du temps et de concevoir comment l'émergence de nouvelles familles est induite lors de périodes de stress environnemental.

Knowledge Map of Research on Biofuels

This work highlights and analyzes the citations and co-citations by different authors, countries and institutions in series of researches on biofuel. These relations represent a knowledge map which shows the areas of research by different countries and authors. The contributions of different institutions were also shown. With this knowledge map developed, areas of research that still need more attention as well as the most important studies were highlighted. The software used for this analysis is Citespace which is developed by Chaomei Chen. Sources of information are articles retrieved from ISI Web of Science. Biofuel as a renewable form of energy is discussed. Its sources, types, methods of production, effects, market, and producers were discussed. Also plans and strategies that aim at boosting world biofuel market were listed as well as recent researches on it. Knowledge mapping, its types and methods as well as the method and software used for the analysis were also discussed.

Research on the suitability of organosolv semi-chemical triticale fibers as reinforcement for recycled hdpe composites

The main objective of this research was to study the feasibility of incorporating organosolv semi-chemical triticale fibers as the reinforcing element in recycled high density polyethylene (HDPE). In the first step, triticale fibers were characterized in terms of chemical composition and compared with other biomass species (wheat, rye, softwood, and hardwood). Then, organosolv semi-chemical triticale fibers were prepared by the ethanolamine process. These fibers were characterized in terms of its yield, kappa number, fiber length/diameter ratio, fines, and viscosity; the obtained results were compared with those of eucalypt kraft pulp. In the second step, the prepared fibers were examined as a reinforcing element for recycled HDPE composites. Coupled and non-coupled HDPE composites were prepared and tested for tensile properties. Results showed that with the addition of the coupling agent maleated polyethylene (MAPE), the tensile properties of composites were significantly improved, as compared to non-coupled samples and the plain matrix. Furthermore, the influence of MAPE on the interfacial shear strength (IFSS) was studied. The contributions of both fibers and matrix to the composite strength were also studied. This was possible by the use of a numerical iterative method based on the Bowyer-Bader and Kelly-Tyson equations

Identification of Turning Points in the Research on Titanium Dioxide Production and Application

This dissertation "Identification of turning points in the research on titanium dioxide production and application" aims at detecting in scientific literatures emerging trends and sudden changes in titanium dioxide production and application. These key changes are then studied to determine its transient patterns and its effect on the research on titanium dioxide production and application The source of information is from bibliographic data which discussed titanium dioxide production and application. These bibliographic data where obtained from ISI Web of Knowledge and then formed into a network of clusters by applying software called Citespace.

Re-evaluating oral poetry : research on the composers ́ field

Lectio praecursoria University of Helsinki 5.2.2011.

Research on Latvian Herrnhutism in the inter-war period

Kirjallisuusarvostelu

Chelyabinsk CHP-3 “locked power” problem solving

All over the world power systems become bigger and bigger every day. New equipment is installed, new feeders are constructed, new power units are installed. Some old elements of the network, however, are not changed in time. As a result, “bottlenecks” for capacity transmission can occur. By locked power problem the situation when a power plant has installed capacity exceeding the power it can actually deliver is usually meant. Regime, scheme or even technical restrictions-related issues usually cause this kind of problem. It is really important, since from the regime point of view it is typical decision to have a mobile capacity reserve, in case of malfunctions. And, what can be even more significant, power plant owner (JSC Fortum in our case) losses his money because of selling less electrical energy. The goal of master`s thesis is to analyze the current state of Chelyabinsk power system and the CHP-3 (Combined Heat and Power plant) in particular in relation with it`s ability to deliver the whole capacity of the CHP in it`s existing state and also taking into consideration the prospect of power unit 3 installation by the fourth quarter of 2010. The thesis contains some general information about the UPS of Russia, CPS of Ural, power system of Chelyabinsk and the Chelyabinsk region itself. Then the CHP-3 is described from technical point of view with it`s equipment observation. Regimes for the nowadays power system and for the system after the power unit 3 installation are reviewed. The problems occurring are described and, finally, a solution is offered.

Micro Data Repositories: Increasing the Value of Research on the Web

Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014