Edge matching puzzles as hard SAT/CSP benchmarks

Recently, edge matching puzzles, an NP-complete problem, have rececived, thanks to money-prized contests, considerable attention from wide audiences. We consider these competitions not only a challenge for SAT/CSP solving techniques but also as an opportunity to showcase the advances in the SAT/CSP community to a general audience. This paper studies the NP-complete problem of edge matching puzzles focusing on providing generation models of problem instances of variable hardness and on its resolution through the application of SAT and CSP techniques. From the generation side, we also identify the phase transition phenomena for each model. As solving methods, we employ both; SAT solvers through the translation to a SAT formula, and two ad-hoc CSP solvers we have developed, with different levels of consistency, employing several generic and specialized heuristics. Finally, we conducted an extensive experimental investigation to identify the hardest generation models and the best performing solving techniques.

The Control of the Edge Shrinkage in Board

Tämän diplomityön tavoitteena oli löytää prosessiparametrejä nestepakkauskartongin reuna-alueiden kuivatuskutistuman hallintaan ja saada tuotteen reuna-alueiden sileystaso paremmaksi. Tarkoituksena oli parantaa reuna-alueiden painettavuusominaisuuksia sekä saada koneen poikkisuunnassa laadultaan parempi tuote. Työn kirjallisuusosassa on tarkasteltu työn kannalta nestepakkauskartongin kriittisimpiä ominaisuuksia, sileyttä ja jäykkyyttä. Lisäksi kirjallisuusosassa on tarkasteltu kuitujen ominaisuuksia, sylinterikuivatusta ja kuivatuskutistumaa. Kokeellisessa osassa on etsitty esitutkimuksella prosessiparametrejä, jotka ovat aiheuttaneet poikkisuunnan sileyserojen kasvun kartonkikoneen investoinnin jälkeen. Suoria korrelaatioita prosessiparametrien ja kuivatuskutistuman välille ei löydetty. Kokeellisen osan tehdasmittakaavaisissa koeajoissa tutkittiin kahdeksan eri parametrin vaikutusta kuivatuskutistumaan, jotka perustuivat kirjallisuuteen. Tutkituista parametreistä huulisuihkun iskukulman muutoksella sekä konesuuntaisella kuivatusprofiililla ei ollut vaikutusta kuivatuskutistumaan. Runkokerroksen mäntysellun korvaaminen koivusellulla vähensi kuivatuskutistumaa ja lisäsi sileyttä, mutta tuotteen palstautumislujuus ei tällöin ollut riittävä. Retentiokemikaalien reseptimuutoksilla pinta- ja taustakerroksen välillä, kuivatusosan nollatason laskulla ja perälaatikkosakeuksien pienentämisellä oli vähän vaikutusta kuivatuskutistumaan. Vaikutus reuna-alueiden sileyteen oli kuitenkin vähemmän kuin 10 %. Diplomityön perusteella kuivatusosan nopeuseroilla ja kuivatusviirojen kireyksillä oli suurin vaikutusta kuivatuskutistumaan ja reuna-alueiden sileystasoon. Lisäämällä nopeuseroja ja kiristämällä kuivatusviiroja reuna-alueiden sileyttä pystyttiin parantamaan yli 20 %.

Statistical mechanics of multi-edge networks

Statistical properties of binary complex networks are well understood and recently many attempts have been made to extend this knowledge to weighted ones. There are, however, subtle yet important considerations to be made regarding the nature of the weights used in this generalization. Weights can be either continuous or discrete magnitudes, and in the latter case, they can additionally have undistinguishable or distinguishable nature. This fact has not been addressed in the literature insofar and has deep implications on the network statistics. In this work we face this problem introducing multiedge networks as graphs where multiple (distinguishable) connections between nodes are considered. We develop a statistical mechanics framework where it is possible to get information about the most relevant observables given a large spectrum of linear and nonlinear constraints including those depending both on the number of multiedges per link and their binary projection. The latter case is particularly interesting as we show that binary projections can be understood from multiedge processes. The implications of these results are important as many real-agent-based problems mapped onto graphs require this treatment for a proper characterization of their collective behavior.

GPRS/EDGE Session Tracing and Analysis in Abis and AGPRS Interfaces

Efficient problem solving in cellular networks is important when enhancing the network performance and liability. Analysis of calls and packet switched sessions in protocol level between the network elements is an important part of this process. They can provide very detailed information about error situations which otherwise would be difficult to recognise. In this thesis we seek solutions for monitoring GPRS/EDGE sessions in two specific interfaces simultaneously in such manner that all information important to the users will be provided in easily understandable form. This thesis focuses on Abis and AGPRS interfaces of GSM radio network and introduces a solution for managing the correlation between these interfaces by using signalling messages and common parameters as linking elements. ~: Finally this thesis presents an implementation of GPRS/EDGE session monitoring application for Abis and AGPRS interfaces and evaluates its benefits to the end users. Application is implemented as a part of Windows based 3G/GSM network analyser.

PREDICTING THE BOILING POINT OF PCDD/Fs BY THE QSPR METHOD BASED ON THE MOLECULAR DISTANCE-EDGE VECTOR INDEX

The quantitative structure property relationship (QSPR) for the boiling point (Tb) of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) was investigated. The molecular distance-edge vector (MDEV) index was used as the structural descriptor. The quantitative relationship between the MDEV index and Tb was modeled by using multivariate linear regression (MLR) and artificial neural network (ANN), respectively. Leave-one-out cross validation and external validation were carried out to assess the prediction performance of the models developed. For the MLR method, the prediction root mean square relative error (RMSRE) of leave-one-out cross validation and external validation was 1.77 and 1.23, respectively. For the ANN method, the prediction RMSRE of leave-one-out cross validation and external validation was 1.65 and 1.16, respectively. A quantitative relationship between the MDEV index and Tb of PCDD/Fs was demonstrated. Both MLR and ANN are practicable for modeling this relationship. The MLR model and ANN model developed can be used to predict the Tb of PCDD/Fs. Thus, the Tb of each PCDD/F was predicted by the developed models.

Does the edge effect influence plant community structure in a tropical dry forest?

Edge effects are considered a key factor in regulating the structure of plant communities in different ecosystems. However, regardless to few studies, edge influence does not seem to be decisive in semiarid regions such as the Brazilian tropical dry forest known as Caatinga but this issue remains inconclusive. The present study tests the null hypothesis that the plant community of shrubs and trees does not change in its structure due to edge effects. Twenty-four plots (20 x 20 m) were set up in a fragment of Caatinga, in which 12 plots were in the forest edges and 12 plots were inside the fragment. Tree richness, abundance and species composition did not differ between edge and interior plots. The results of this study are in agreement with the pattern previously found for semiarid environments and contrasts with previous results obtained in different environments such as Rainforests, Savanna and Forest of Araucaria, which indicate abrupt differences between the border and interior of the plant communities in these ecosystems, and suggest that the community of woody plants of the Caatinga is not ecologically affected by the presence of edges.

Changes in plant community diversity and composition across an edge between Araucaria forest and pasture in South Brazil

This work investigated how richness, abundance, composition and structure of woody and herbaceous vegetation were altered by the proximity of an edge between Araucaria forest and pasture in South Brazil. Herbaceous and woody species including seedlings were surveyed in 42 plots of 5 × 5 m randomly placed at the following distances: 5 and 50 m from the edge into the pasture and 0, 25, 50, 100 and 250 m from the edge into the forest. There was a significant increase in vegetation cover, richness and abundance of woody species, woody seedlings and herbaceous plants at the edge (0 m). These variables, in general, decreased from 25 to 50 m from the edge into the forest in comparison to the forest interior. Few seedlings of woody plants were able to establish themselves in the pasture. There were continuous changes in species composition that occurred in the studied gradient due to the invasion of light-demanding species and the disappearance of some shade-tolerant species at the edge. In conclusion, the forest edge studied generated changes in the plant community that extended up to 50 m into the forest.

On the edge : exploring homeless women's social networks

This thesis aims to uncover the ways that previously homeless women in the Niagara region are able (or unable) to rely on friends, family and service providers in times of crisis (homelessness and poverty). Eleven women were interviewed and their experiences indicate that social networks cannot take the place of comprehensive and inclusive social policy. Time and time again, their stories showed that they were left negotiating the detritus of neo-liberal policies.

Pausing at the river's edge : a narrative inquiry into the practice of a reading teacher /

In this narrative self-study I retell and connect the stories ofmy personal journey with literacy from childhood to the present. I use narrative as both methodology and method as I story my life experiences and my personal encounters with literacy. The heart ofmy reflections comes from the pages of personal journals written and storied over many years of trying to make meaning of powerful literacy experiences in my life. Now, in going back through the stories and reconstructing meaning, I make connections between the memories along the journey and the place from which I now tell my story. The interpretations I construct give voice to beliefs 1 have lived by and illuminations to moments in time that I have come to see with new eyes as I have engaged in this inquiry. The journey and self-reflection within the pages of this inquiry provide understanding of the driving force behind my personal passion for literacy. I am better able to understand my motivations and share the stories that validate my personal and professional path through time.

The investigation of edge effects within ragmented forest islands in Short Hills Provincial Park

It has been well documented, within the field of landscape ecology, that terrestrial fragmentation contributes to increased heterogeneity at the landscape level. It has also been observed that elevated areas of edge habitat occur within fragmented landscapes. Spatial and temporal edge effects were investigated in four areas designated as Nature Reserve Zones within Short Hills Provincial Park, near St. Catharines, Ontario. Random sampling along exposed edges was performed on trees and saplings, at 5 and 25 ill edge depths, using the point-centred quarter method. Diameter at breast height (dbh) and distance from point measurements were used to establish relative density, dominance, frequency and importance value. One-way analyses of variance were used on dbh measurements of tree species and Chi-Square contingency tables were used on size class distributions of saplings species to determine significant differences between 5 and 25 metres. Qualitative comparisons of importance values were also used to determine differences between 5 and 25 metres as well as between trees and saplings. These statistical and qualitative comparisons suggest that a significant overall spatial edge effect is currently exhibited by fragmented wooded islands within the park. The major species of the park, Acersaccharuln, may be exhibiting a temporal edge effect. The heterogeneous nature of the park may be of importance in understanding this area as a complex, ecological system. It is possible that the remaining forest tracts of the park have been affected, and continue to be affected by previous disturbances. Based on these findings, recommendations are made to the Ontario Ministry of Natural Resources concerning the management of Short Hills Provincial Park in accordance with their 1990 proposed Management Plan.

Edge-choosability of Planar Graphs

According to the List Colouring Conjecture, if G is a multigraph then χ' (G)=χl' (G) . In this thesis, we discuss a relaxed version of this conjecture that every simple graph G is edge-(∆ + 1)-choosable as by Vizing’s Theorem ∆(G) ≤χ' (G)≤∆(G) + 1. We prove that if G is a planar graph without 7-cycles with ∆(G)≠5,6 , or without adjacent 4-cycles with ∆(G)≠5, or with no 3-cycles adjacent to 5-cycles, then G is edge-(∆ + 1)-choosable.

Dissecting cell cycle protein complexes using the pptimized yeast cytosine deaminase protein-fragment complementation assay “You too can play with an edge”

Les protéines sont les produits finaux de la machinerie génétique. Elles jouent des rôles essentiels dans la définition de la structure, de l'intégrité et de la dynamique de la cellule afin de promouvoir les diverses transformations chimiques requises dans le métabolisme et dans la transmission des signaux biochimique. Nous savons que la doctrine centrale de la biologie moléculaire: un gène = un ARN messager = une protéine, est une simplification grossière du système biologique. En effet, plusieurs ARN messagers peuvent provenir d’un seul gène grâce à l’épissage alternatif. De plus, une protéine peut adopter plusieurs fonctions au courant de sa vie selon son état de modification post-traductionelle, sa conformation et son interaction avec d’autres protéines. La formation de complexes protéiques peut, en elle-même, être déterminée par l’état de modifications des protéines influencées par le contexte génétique, les compartiments subcellulaires, les conditions environmentales ou être intrinsèque à la croissance et la division cellulaire. Les complexes protéiques impliqués dans la régulation du cycle cellulaire sont particulièrement difficiles à disséquer car ils ne se forment qu’au cours de phases spécifiques du cycle cellulaire, ils sont fortement régulés par les modifications post-traductionnelles et peuvent se produire dans tous les compartiments subcellulaires. À ce jour, aucune méthode générale n’a été développée pour permettre une dissection fine de ces complexes macromoléculaires. L'objectif de cette thèse est d'établir et de démontrer une nouvelle stratégie pour disséquer les complexes protéines formés lors du cycle cellulaire de la levure Saccharomyces cerevisiae (S. cerevisiae). Dans cette thèse, je décris le développement et l'optimisation d'une stratégie simple de sélection basée sur un essai de complémentation de fragments protéiques en utilisant la cytosine déaminase de la levure comme sonde (PCA OyCD). En outre, je décris une série d'études de validation du PCA OyCD afin de l’utiliser pour disséquer les mécanismes d'activation des facteurs de transcription et des interactions protéine-protéines (IPPs) entre les régulateurs du cycle cellulaire. Une caractéristique clé du PCA OyCD est qu'il peut être utilisé pour détecter à la fois la formation et la dissociation des IPPs et émettre un signal détectable (la croissance des cellules) pour les deux types de sélections. J'ai appliqué le PCA OyCD pour disséquer les interactions entre SBF et MBF, deux facteurs de transcription clés régulant la transition de la phase G1 à la phase S. SBF et MBF sont deux facteurs de transcription hétérodimériques composés de deux sous-unités : une protéine qui peut lier directement l’ADN (Swi4 ou Mbp1, respectivement) et une protéine commune contenant un domain d’activation de la transcription appelée Swi6. J'ai appliqué le PCA OyCD afin de générer un mutant de Swi6 qui restreint ses activités transcriptionnelles à SBF, abolissant l’activité MBF. Nous avons isolé des souches portant des mutations dans le domaine C-terminal de Swi6, préalablement identifié comme responsable dans la formation de l’interaction avec Swi4 et Mbp1, et également important pour les activités de SBF et MBF. Nos résultats appuient un modèle où Swi6 subit un changement conformationnel lors de la liaison à Swi4 ou Mbp1. De plus, ce mutant de Swi6 a été utilisé pour disséquer le mécanisme de régulation de l’entrée de la cellule dans un nouveau cycle de division cellulaire appelé « START ». Nous avons constaté que le répresseur de SBF et MBF nommé Whi5 se lie directement au domaine C-terminal de Swi6. Finalement, j'ai appliqué le PCA OyCD afin de disséquer les complexes protéiques de la kinase cycline-dépendante de la levure nommé Cdk1. Cdk1 est la kinase essentielle qui régule la progression du cycle cellulaire et peut phosphoryler un grand nombre de substrats différents en s'associant à l'une des neuf protéines cycline régulatrice (Cln1-3, Clb1-6). Je décris une stratégie à haut débit, voir à une échelle génomique, visant à identifier les partenaires d'interaction de Cdk1 et d’y associer la cycline appropriée(s) requise(s) à l’observation d’une interaction en utilisant le PCA OyCD et des souches délétées pour chacune des cyclines. Mes résultats nous permettent d’identifier la phase(s) du cycle cellulaire où Cdk1 peut phosphoryler un substrat particulier et la fonction potentielle ou connue de Cdk1 pendant cette phase. Par exemple, nous avons identifié que l’interaction entre Cdk1 et la γ-tubuline (Tub4) est dépendante de Clb3. Ce résultat est conforme au rôle de Tub4 dans la nucléation et la croissance des faisceaux mitotiques émanant des centromères. Cette stratégie peut également être appliquée à l’étude d'autres IPPs qui sont contrôlées par des sous-unités régulatrices.

The Edge C4 Graph of a Graph

Abstract. The edge C4 graph E4(G) of a graph G has all the edges of Gas its vertices, two vertices in E4(G) are adjacent if their corresponding edges in G are either incident or are opposite edges of some C4. In this paper, characterizations for E4(G) being connected, complete, bipartite, tree etc are given. We have also proved that E4(G) has no forbidden subgraph characterization. Some dynamical behaviour such as convergence, mortality and touching number are also studied

Studies on the Development and Control of Desiccation cracks in compacted clay liner soils

The present study aimed at critically looking at the current practice of the installation of compacted clay liner using bentonite enhanced sand (BES). The application of bentonite is currently the most accepted practice for lining purposes. The ideal bentonite sand combination, which satisfies the liner requirements is 20% bentonite and 80% sand, was selected as one of the liner materials for the investigation of development of desiccation cracks. Locally available sundried marine clay and its combination with bentonite were also included in the study. The desiccation tests on liner materials were conducted for wet/dry cycles to simulate the seasonal variations. Digital image processing techniques were used to measure the crack intensity factor (CIF), a useful and effective parameter for quantification of desiccation cracking. The repeatability of the tests could be well established, as the variation in CIF values of identical samples had a very narrow range of 0 to 2%. The studies on the development of desiccation cracks showed that the CIF of bentonite enhanced sand mixture (BES) was 18.09%, 39.75% and 21.22% for the first, second and third cycles respectively, while it was only 9.83%, 7.52% and 4.58% respectively for sun dried marine clay (SMC). Thus the locally available, alternate liner material suggested, viz SMC, is far superior to BES, when subjected to alternate wet/dry cycles. Further, the improvement of these liner materials when amended with randomly distributed fibre reinforcements was also investigated. Three types of fibres ,namely nylon fibre, polypropylene monofilament and polypropylene fibre mesh were used for the study of fibre amended BES and SMC.The influence of these amendments on the properties of the above liner materials is also studied. The results showed that there is definite improvement in the properties of the liner materials when it is reinforced with discrete random fibres. The study also proved that the desiccation cracks could be controlled with the help of fibre reinforcement.