Magíster en Ciencias, Mención Computación / El principal objetivo de esta tesis es encontrar casos tratables y buenas técnicas para computar Certain Answers sobre bases de datos de grafos incompletas, en tiempo polinomial. Las bases de datos de grafos surgen naturalmente de la necesidad de almacenar información de redes, tales como Facebook, mapas de rutas o la web. La idea de "incompletitud" viene de la falta de información completa, complejidad con la cual tenemos que trabajar a diario. Sobre estas bases de datos de grafos carentes de información completa, queremos realizar preguntas en la forma de consultas particulares y determinar si la pregunta puede ser contestada de la misma forma en cada posible completación de la base de datos. La respuesta a estas preguntas en cada posible completación de una base de datos de grafos incompleta es llamada Certain Answers. El problema de Certain Answers sobre bases de datos de grafos incompletas ya ha sido estudiado, y es conocido que este problema es en general co-NP completo. En esta tesis convertimos el problema de computar Certain Answers en un problema 3-SAT con su fórmula lógica booleana asociada. Podemos probar que bajo ciertas condiciones esta fórmula lógica tiene un número de variables que nos permite determinar si es satisfacible en tiempo polinomial. Luego, probamos que estas condiciones son exhaustivas: sin cualquiera de ellas el problema se vuelve co-NP completo otra vez. Para analizar más clases tratables del problema de Certain Answers, convertimos el problema Certain Answers en un problema de programación lineal entera. Con esta formulación de programación lineal, encontramos algunos casos tratables, algoritmos y heurísticas para resolverlo. Sin embargo, el principal logro es la nueva formulación en sí, porque nos permite usar las bien conocidas técnicas de programación lineal para encontrar más casos tratables y mejores heurísticas.

Origin and purpose of research Dichloro-diphenyl-trichloroethane or DDT as it is more commonly known, was first used extensively by the armed forces in the Pacific Area during World War II. This insecticide is not only a very toxic contact and stomach poison, but also is quite residual on most types of surfaces. Because of these qualities, it was selected to control the malaria mosquito and thus aided in the conquest of many disease-ridden islands of the Pacific. When DDT became available to the general public after the war, it was found not only to be effective against mosquitoes but also many other types of insects. Among these insects are the alfalfa weevil (Hypera postica hon.) and lygus bugs (Lygus elisus Van D., Lygus hesperus Knight) that had previously impaired the production of alfalfa in Utah and other areas. Although treatment of alfalfa fields is usually confined to alfalfa for seed production, DDT-dusted alfalfa straw and DDT dusted alfalfa hay are fed to farm livestock. In ruminant animals, microorganisms play an important role in the synthesis of protein from nitrogenous non-protein compounds and also aid in the break-down of many complex plant materials so that they may be more fully utilized by these animals. The purpose of this study was to determine the effect of DDT upon the role played by the microflora and fauna of the rumen in the synthesis, digestion and utilization of certain nutrients by dairy calves. Scope Digestion and balance studies were conducted with Holstein bull calves fed different levels of DDT and protein equivalent in the ration. The experiment was designed so that each calf would receive one level of DDT throughout the experiment, and would receive a low protein basal diet plus three additional levels of protein equivalent. These additional protein levels were made up by adding a nitrogenous non-protein compound, urea, to the basal diet to give an increased level of protein equivalent in the diet. The nitrogen, calcium, and phosphorus balance and the digestibility of dry matter, protein, and ether extract were determined.

Due to the commercial importance of barley many hybridization studies have been prosecuted in an effort to produce superior economic strains. While the economic breeding is still important, at present there is considerable scientific interest int he inheritance of the characters and in the location of the genes in the different linkage groups. Barley is rather favorable genetic material for such study. There is a great number of cultivated varieties and strains which differ widely in heritable characters. Barley can be grown under a wide range of climatic conditions and will produce rather large F2 families. The fact that it has only seven chromosomes makes linkage studies more feasible than in wheat or oats with their greater chromosome complements. The characters studied in this paper are: black versus white glume color, long haired versus short haired rachilla, rough versus smooth awns, and branched versus unbranched style.

Studies were conducted to determine the effect of externally applied growth hormones on winter rye (Secale cereale var. cougar). The rye was grown under the snow in a specially prepared tunnel on a mountain side near Logan, Utah. These plants showed a remarkable ability to grow at 0°C. Three growth hormones, kinetin, gibberellic acid (GA), and auxin (indole-3-acetic acid) were externally applied to rye seedlings growing in the tunnel. These seedlings were alter weighed, measured and tested for soluble protein content. The three hormone treatments had no significant effects on the fresh weights or shoot lengths of the rye. GA however, had a significant effect on the soluble protein content of the young shoots. Shoots treated with GA showed a marked decrease in soluble protein content. Kinetin and IAA had no significant effect on the soluble protein content of the rye.

Cette thèse s’inscrit dans un projet de cerner des modes d’expression de la quantification dont le statut paraît plus marginal que d’autres. À côté d’une abondante littérature sur les déterminants quantifieurs, par exemple, l’étude des locutions adverbiales quantifiantes et intensifiantes n’est pas encore très élaborée. La présente étude se consacre en conséquent à une locution adverbiale à la marge de l’analyse de la quantification : jusqu’à un certain point. Elle s’appuie sur un corpus (écrit) d’occurrences tirées de différentes sources. La première partie présente trois études individuelles sur les lexies qui constituent la locution, la préposition jusque, le déterminant complexe un certain et le nom point. La deuxième partie présente une vue d’ensemble des emplois contemporains de jusqu’à un certain point, démontre le figement de la locution en synchronie et dresse le tableau de son évolution depuis son apparition dans Frantext en 1671. Six emplois actuels se dégagent : endophrastique, jusqu’à un certain point fonctionne comme un adverbe de complétude, de degré ou « limitatif ». Exophrastique, la locution fonctionne comme un adverbe modal, une enclosure (shield ou approximator). Il existe des occurrences hybrides entre quantification et modalisation. Enfin, la locution peut fonctionner comme un pivot argumentatif qui a des propriétés d’un modalisateur déréalisant. La troisième partie examine le statut d’adverbial de jusqu’à un certain point, son interaction avec différents types de prédicats, le rôle que joue sa position dans l’énoncé, sa conceptualisation sur un mode cognitiviste et son rôle d’opérateur discursif participant à l’agencement de l’argumentation. / This thesis stems from a project aimed at exploring marginal quantifying expressions. Whereas there is an abundant literature on quantifying determiners, for instance, the study of quantifying/intensifying adverbial phrases is not very advanced yet. This thesis thus focuses on a quantifying adverbial phrase on the margins of quantification research: jusqu’à un certain point (to a certain extend/up to a certain point). The analysis is based on a written corpus using different sources. Part one offers three studies of the adverbial phrase’s constituents, the preposition jusque, the determiner un certain and the noun point. Part two introduces an overview of the current uses of jusqu’à un certain point, shows the adverbial phrase’s synchronic fixation and describes its evolution since its first appearance in Frantext in 1671. Six contemporary uses can be distinguished: endophrastic jusqu’à un certain point functions as an adverb of completion, degree or “limit”. Exophrastic jusqu’à un certain point functions as a modal, a hedge (shield or approximator). There are hybrid cases activating quantitative and modal values in parallel. Finally, the adverbial phrase can function as an argumentative pivot with properties of a modalisateur déréalisant of Ducrot. Part three examines the adverbial status of jusqu’à un certain point, its interaction with different predicate types, the role played by its syntactical position, its conceptualization within a cognitive semantic perspective and its role as a discourse operator participating in the articulation of argumentation.

The purpose of this study was to determine the accuracy of mapping of pachic and cumulic soils in Cache County. The soil maps that were used for this study as the basemap were the Atlas sheets of the published soil survey of Cache County. Five map units from Mendou, Nebeker, Avon, Hendricks and Winn which include almost 52 percent of the pachic and cumulic soils in the survey area were selected for this study. These five soils cover large areas when compared to other soil series and they are distributed throughout the county. All these map units were recognized as pachic and cumulic in the published soil survey report. The thickness of the epipedon was therefore selected as the principal criterion for determining the accuracy of the map units. About 400 samples from the major delineations were studied in the field and the necessary data were collected and interpreted statistically in order to find: (1) the accuracy of each map unit, (2) the inclusions, misclassified and not classified pedons and their proportions, and (3) the estimated thickness of the epipedons. Attempts were made to select the pedons on transects with appropriate interval, depending on landforms and continuity of soils. Statistical interpretations were conducted by using the chi-square method. The results for each map units are as follows: for Mendon map unit (MeA) 42-56 percent and for Hendricks map unit (HdD) only 30-60 percent of the samples have characteristics required for the named soil in these map units. These values are less than 75 percent which is the critical value for the map units by definition. It is concluded therefore that with the available data the Mendon and Hendricks series have been mapped incorrectly. For Nebeker map unit (NbE) 77-93 percent and from Avon map unit (ArA) 85-99 percent of the samples have the characteristics required for the named soil in the map units. These values are more than the critical value (75) so it is concluded that with available data the Nebeker and Avon series have been mapped correctly. For Winn map unit (Wn) 54-82 percent of the samples have the required characteristics of this series. The statistical analysis did not reveal strictly whether the pedons are mapped correctly or not and additional samples are required to adequately test the accuracy of the Winn map unit. It is concluded that in Cache County the influence of different geologic depositions and variations in topography are two major factors responsible for poor accuracy in mapping the Mendon and Hendricks series.

During recent years the principles of Mendelism have been used extensively in the production of the new types of plants possessing resistance to various diseases. Results of this mode of attacking the disease problem have been very favorable. Old varieties are gradually giving way to newer types equal to or exceeding in quality and productivity as well as possessing resistance to one or more diseases. Loose smut (U. tritici) in wheat, while not as serious a problem in Utah as the covered smut (T. tritici), according to Tapke (14) has caused an average annual loss of between 50,000 and 100,000 bushels of wheat. these data shown in figure 1 are for the period 1917 to 1926, inclusive. The various methods advocated for the control of loose smut (U. tritici), with the exception of the use of resistant varieties and hot water treatments, either have been impradtical of application or have been ineffective in control or both (14). The modified hot water treatment of Freeman and Johnson (4), has generally been the method recommended. While this method is effective if properly executed, it is rather complicated and tedious to apply, especially for farmers who are not usually properly equipped. Because of this and the fact that the disease frequently escapes observation, seed treatment for the control of loose smut (U. tritici) is seldom practiced; as a result the smut is allowed to go unchecked. The development of a resistant variety possessing the adaptability and desirable characteristics of our locally-grown spring wheats would be a decided advantage to the farmers in combating the disease.

Characteristics and genesis of five pedons representing some of the soils of the central Alborz mountain northeast of Tehran were investigated. The present climate of the area is similar to the Mediterranean climate. The parent materials for the soils under study have apparently been derived from the Ecocene Alborz Green Beds (a thinly bedded light green mudstone), the Pliocene Hezardareh Formation (a poorly-cemented conglomerate) and Recent alluvium and colluvium. Pedons 2 and 4 are located at lower elevations (plain and river terraces) on 1 to 2 percent slopes. Pedons 3 and 5 are located at higher elevations (hills that surround the valley) on steep slopes of 60 to 75 percent. According to the results obtained from the physical, chemical, mineralogical, and micromorphological analyses, the pedons have been classified as Xeric Torriorthent--loamy-skeletal, mixed, thermic (pedon 1); Vertic Xerochrept--fine, mixed, thermic (pedon 2); Xerollic Calciorthid--loamy-skeletal, mixed, thermic (pedon 3); Xerollic Calciorthid--fine, mixed, thermic (pedon 4); and Argic Calciorthid--clayey-skeletal, mixed thermic (pedon 5). The studies on the genesis of the soils were summarized as follows: 1. Wind deposition has affected the top layer of the eroded surfaces of the five pedons. The process has incorporated silt and very fine sand materials into these layers. 2. The differences in landform stability, and consequently, the various degree of the influence of the erosion-deposition processes, are believed to be responsible for the differences in the horizon differentiation of the pedons. The steepness of sloper rather than age of the landform was responsible for the present morphology of the pedons. 3. Pedons 1 to 4 are Recent in age but the control section of pedon 5 reflects an age of Pleistocene or older and, therefore, a wetter climate than at present. 4. The clay mineralogy and the texture of the control section of the pedons reflect the greater influence of the parent materials than any other factor of pedogenesis. It was suggested that for the Aridisols with moisture regimes bordering on Xeric, the required electrical conductivity of more than 2 millimhos per centimeter be eliminated from the differentiating criteria in Soil Taxonomy.

Abstract In Sweden all persons under the age of 18 are considered children. The age when it is possible to be held responsible for a criminal act, and therefor convicted in court, is 15. Society’s and, perhaps first and foremost, the authority’s attitude towards juvenile crime is that they should not be equal adults in the process within criminal law. Because children are considered essential for the society of tomorrow, it is important to pay extra attention to crimes committed by juveniles. The social services authorities are considered to have the best resources and competence to handle this group of juveniles. In the criminal law process the prosecutor requests a statement regarding the young person who is reasonably suspected of a criminal act. The statement should contain information about if the young person is in need of certain interventions from social services in order to prevent unfavorable development. The conclusion that has been drawn when the statements has been reviewed is that a borderland has been created where social law and criminal law overlap. This overlapping is in a way a collision where social aspects and principles of criminal law have to meet. However, it is not always easy to make both sides satisfied. As a way to meet the needs of both sides the borderland becomes a compromise consisting of the process regarding the juveniles. The purpose of this essay is to describe and understand the compromise that has been made where statements and young juveniles are existing. The aim of this essay is to study 23 statements from social services that prosecutor request and the 23 court records attached to them. All statements and court records are regarding persons between 15 – 17 years old. The study is limited to the period between 2010-01-01 to 2010-12-31. This essay has been from a qualitative point of view where the discourse analysis as an text analytical method has been used to understand the collected statements and court records. Central results is that the statements reviewed in this essay overall are satisfying in fulfilling the social law and criminal law aspects. However the results also point out that an uncertainty within the social services regarding the design of the statements also is to be found. Descriptions of social aspects about the young juvenile behind the statement seems to be important to emphasize.

I divided this new type of composition, multi-type composition of a certain topic, into five categories, and the composition themes were designed in person by me; I also put them into practice in my teaching procedure in the junior high school composition class. After finishing collecting student works, I spent very long time classifying and commenting on them, and finally found that students had quite excellent performing in two respects, one is confirming the main ideas of the composition themes and how students chose their composition materials is the other. In this thesis I shall present the result of my study completely, including my designed composition themes, the teaching procedures of every theme, student works and given comments of those works.