Academic literature on the topic 'Maximum average degree'

Dans cette thèse, nous nous intéressons à différentes notions de colorations sous contraintes. Nous nous intéressons plus spécialement à la coloration acyclique, à la coloration forte d'arêtes et à la coloration d'arêtes sommets adjacents distinguants.Dans le Chapitre 2, nous avons étudié la coloration acyclique. Tout d'abord nous avons cherché à borner le nombre chromatique acyclique pour la classe des graphes de degré maximum borné. Ensuite nous nous sommes attardés sur la coloration acyclique par listes. La notion de coloration acyclique par liste des graphes planaires a été introduite par Borodin, Fon-Der Flaass, Kostochka, Raspaud et Sopena. Ils ont conjecturé que tout graphe planaire est acycliquement 5-liste coloriable. De notre côté, nous avons proposé des conditions suffisantes de 3-liste coloration acyclique des graphes planaires. Dans le Chapitre 3, nous avons étudié la coloration forte d'arêtes des graphes subcubiques en majorant l'indice chromatique fort en fonction du degré moyen maximum. Nous nous sommes également intéressés à la coloration forte d'arêtes des graphes subcubiques sans cycles de longueurs données et nous avons également obtenu une majoration optimale de l'indice chromatique fort pour la famille des graphes planaires extérieurs. Nous avons aussi présenté différents résultats de complexité pour la classe des graphes planaires subcubiques. Enfin, au Chapitre 4, nous avons abordé la coloration d'arêtes sommets adjacents distinguants en déterminant les majorations de l'indice avd-chromatique en fonction du degré moyen maximum. Notre travail s'inscrit dans la continuité de celui effectué par Wang et Wang en 2010. Plus précisément, nous nous sommes focalisés sur la famille des graphes de degré maximum au moins 5.

Le Théorème des Quatre Couleurs, conjecturé en 1852 et prouvé en 1976, est à l'origine de l'étude des partitions des sommets de graphes peu denses. Il affirme que toute carte plane peut être coloriée avec au plus quatre couleurs différentes, de telle manière que deux régions qui partagent une frontière aient des couleurs différentes. Énoncé en terme de théorie des graphes, cela veut dire que tout graphe planaire, c'est à dire tout graphe qui peut être représenté dans le plan sans que deux arêtes ne se croisent, peut voir son ensemble de sommets partitionné en quatre ensembles tels que chacun de ces ensembles ne contient pas les deux extrémités d'une même arête. Une telle partition est appelée une coloration propre en quatre couleurs. Dans cette thèse, on s'intéresse à l'étude de la structure des graphes peu denses, selon différentes notions de densité. D'une part, on étudie les graphes planaires sans petits cycles, et d'autre part les graphes dont tous les sous-graphes ont un degré moyen peu élevé. Pour ces classes de graphes, on recherche tout d'abord le plus petit nombre de sommets à retirer pour obtenir une forêt, c'est à dire un graphe sans cycles. Cela peut être vu comme une partition des sommets du graphe en un ensemble induisant une forêt et un ensemble de sommets contenant au plus une fraction donnée des sommets du graphe. La motivation première de cette étude est une conjecture d'Albertson et Berman (1976) comme quoi tout graphe planaire admettrait une telle partition où la forêt contient au moins la moitié des sommets du graphe. Dans un second temps, on s'intéresse aux partitions des sommets de ces graphes en deux ensembles, tels que les sous-graphes induits par ces deux ensembles ont des propriétés particulières. Par exemple, ces sous-graphes peuvent être des graphes sans arêtes, des forêts, des graphes de degré borné, ou des graphes dont les composantes connexes ont un nombre borné de sommets. Ces partitions des sommets sont des extensions de la notion de coloration propre de graphe.On montre, pour différentes classes de graphes peu denses, que tous les graphes de ces classes admettent de telles partitions. On s'intéresse également aux aspect algorithmiques de la construction de telles partitions
The study of vertex partitions of planar graphs was initiated by the Four Colour Theorem, which was conjectured in 1852, and proven in 1976. According to that theorem, one can colour the regions of any planar map by using only four colours, in such a way that any two regions sharing a border have distinct colours. In terms of graph theory, it can be reformulated this way: the vertex set of every planar graph, i.e. every graph that can be represented in the plane such that edges do not cross, can be partitioned into four sets such that no edge has its two endpoints in the same set. Such a partition is called a proper colouring of the graph.In this thesis, we look into the structure of sparse graphs, according to several notions of sparsity. On the one hand, we consider planar graphs with no small cycles, and on the other hand, we consider the graphs where every subgraph has bounded average degree.For these classes of graphs, we first look for the smallest number of vertices that can be removed such that the remaining graph is a forest, that is a graph with no cycles. That can be seen as a partition of the vertices of the graph into a set inducing a forest and a set with a bounded fraction of the vertices of the graph. The main motivation for this study is a the Albertson and Berman Conjecture (1976), which states that every planar graph admits an induced forest containing at least one half of its vertices.We also look into vertex partition of sparse graphs into two sets both inducing a subgraph with some specific prescribed properties. Exemples of such properties can be that they have no edges, or no cycles, that they have bounded degree, or that they have bounded components. These vertex partitions generalise the notion of proper colouring. We show, for different classes of sparse graphs, that every graph in those classes have some specific vertex partition. We also look into algorithmic aspects of these partitions

Dans cette thèse, nous nous intéressons à differentes colorations des sommets d’un graphe et aux homomorphismes de graphes. Nous nous intéressons plus spécialement aux graphes planaires et aux graphes peu denses. Nous considérons la coloration propre des sommets, la coloration acyclique, la coloration étoilée, lak-forêt-coloration, la coloration fractionnaire et la version par liste de la plupart de ces concepts.Dans le Chapitre 2, nous cherchons des conditions suffisantes de 3-liste colorabilité des graphes planaires. Ces conditions sont exprimées en termes de sous-graphes interdits et nos résultats impliquent plusieurs résultats connus.La notion de la coloration acyclique par liste des graphes planaires a été introduite par Borodin, Fon-Der Flaass, Kostochka, Raspaud, et Sopena. Ils ont conjecturé que tout graphe planaire est acycliquement 5-liste coloriable. Dans le Chapitre 3, on obtient des conditions suffisantes pour qu’un graphe planaire admette une k-coloration acyclique par liste avec k 2 f3; 4; 5g.Dans le Chapitre 4, nous montrons que tout graphe subcubique est 6-étoilé coloriable.D’autre part, Fertin, Raspaud et Reed ont montré que le graphe de Wagner ne peut pas être 5-étoilé-coloriable. Ce fait implique que notre résultat est optimal. De plus, nous obtenons des nouvelles bornes supérieures sur la choisissabilité étoilé d’un graphe planaire subcubique de maille donnée.Une k-forêt-coloration d’un graphe G est une application ¼ de l’ensemble des sommets V (G) de G dans l’ensemble de couleurs 1; 2; ¢ ¢ ¢ ; k telle que chaque classede couleur induit une forêt. Le sommet-arboricité de G est le plus petit entier ktel que G a k-forêt-coloration. Dans le Chapitre 5, nous prouvons une conjecture de Raspaud et Wang affirmant que tout graphe planaire sans triangles intersectants admet une sommet-arboricité au plus 2.Enfin, au Chapitre 6, nous nous concentrons sur le problème d’homomorphisme des graphes peu denses dans le graphe de Petersen. Plus précisément, nous prouvons que tout graphe sans triangles ayant un degré moyen maximum moins de 5=2 admet un homomorphisme dans le graphe de Petersen. En outre, nous montrons que la borne sur le degré moyen maximum est la meilleure possible
In this thesis, we are interested in various vertex coloring and homomorphism problems of graphs with special emphasis on planar graphs and sparsegraphs. We consider proper vertex coloring, acyclic coloring, star coloring, forestcoloring, fractional coloring and the list version of most of these concepts.In Chapter 2, we consider the problem of finding sufficient conditions for a planargraph to be 3-choosable. These conditions are expressed in terms of forbiddensubgraphs and our results extend several known results.The notion of acyclic list coloring of planar graphs was introduced by Borodin,Fon-Der Flaass, Kostochka, Raspaud, and Sopena. They conjectured that everyplanar graph is acyclically 5-choosable. In Chapter 3, we obtain some sufficientconditions for planar graphs to be acyclically k-choosable with k 2 f3; 4; 5g.In Chapter 4, we prove that every subcubic graph is 6-star-colorable. On theother hand, Fertin, Raspaud and Reed showed that the Wagner graph cannot be5-star-colorable. This fact implies that our result is best possible. Moreover, weobtain new upper bounds on star choosability of planar subcubic graphs with givengirth.A k-forest-coloring of a graph G is a mapping ¼ from V (G) to the set f1; ¢ ¢ ¢ ; kgsuch that each color class induces a forest. The vertex-arboricity of G is the smallestinteger k such that G has a k-forest-coloring. In Chapter 5, we prove a conjecture ofRaspaud and Wang asserting that every planar graph without intersecting triangleshas vertex-arboricity at most 2.Finally, in Chapter 6, we focus on the homomorphism problems of sparse graphsto the Petersen graph. More precisely, we prove that every triangle-free graph withmaximum average degree less than 5=2 admits a homomorphism to the Petersengraph. Moreover, we show that the bound on the maximum average degree in ourresult is best possible

Esse trabalho teve como objetivo comparar métodos de estimação de componentes de variância e parâmetros genéticos, considerando tanto o delineamento estatístico fatorial instalado em látice quadrado como o delineamento genético III. Como referência, foram utilizados três conjuntos de dados reais, em melhoramento genético de milho, relativos aos caracteres de produção de grãos (gramas por parcela), altura da folha bandeira ao chão (centímetros) e o número de folhas entre a primeira espiga e o pendão; sendo que a altura da folha bandeira e o número de folhas foram obtidos pela média entre cinco plantas competitivas para cada parcela. O método da Análise da Variância (ANOVA), conforme indicado pelo Delineameno III, foi utilizado na análise dos dados e estimação dos componentes de variância relativos ao modelo matemático, variâncias genéticas, coeficiente de herdabilidade e grau médio de dominância para cada um dos três caracteres estudados. Essas estimativas foram utilizadas na simulação de 1000 conjuntos de dados com características semelhantes a cada um dos conjuntos de dado reais considerados. Os métodos da ANOVA e da máxima verossimilhança restrita (REML) foram utilizados na predição dos parâmetros já mencionados para cada um dos conjuntos de dados simulados dentro de cada caráter. As 1000 estimativas obtidas por cada método, para cada caráter estudado, foram utilizadas no cálculo de estatísticas descritivas (média, desvio-padrão e acurácia relativa) e na montagem de gráficos de Box-plot. Utilizando as informações obtidas a partir das estimativas fornecidas por cada método e em posse dos valores reais que essas estimativas deveriam prever (valor utilizado na simulação dos dados) foi possível comparar ambos os métodos quanto à eficiência das estimativas por eles fornecidas. Ambos os métodos apresentaram características semelhantes na predição da maioria dos componentes de variância relativos ao modelo matemático, sendo que as maiores disparidades se deram para os componentes relativos aos efeitos de progênie (?p2) e as interações entre progênie e linhagem (?pt2) e entre progênie, linhagem e ambiente (?pta2); os quais são os componentes de maior peso no cálculo das variâncias e parâmetros genéticos. O método da ANOVA foi o bastante eficiente na predição de ?p2, sendo que o método da REML se aproxima dos resultados obtidos pelo método da ANOVA conforme diminuem os valores de referência para esse componente; para ?pt2 o método da REML se mostrou mais eficiente conforme maior é o valor de referência, porém, perde eficiência e se aproxima do método da ANOVA conforme o valor de referência do componente diminui. Ambos os métodos se mostraram ineficientes na predição de ?pta2, porém o método da REML foi o menos eficiente. O melhor desempenho do método da ANOVA na predição dos componentes de variância de maior peso no cálculo das variâncias genéticas levou a um melhor desempenho desse método na predição de todos os parâmetros genéticos, com exceção da variância de dominância, a qual depende unicamente de ?pt2. Porém, foi observada uma tendência no método da ANOVA, em média, na superestimação do grau médio de dominância em cerca de 45% do seu valor de referência, independentemente do caráter estudado.
This work aimed to compare estimation methods for variance components and genetic parameters, considering the factorial statistical design set in randomized blocks and the genetic Design III. As reference, three sets of real data were used, on maize genetic improvement, related to the characters: grain yield (grams by plot), plant height, measured from the ground to the °ag leaf in centimeters, and the number of leaves above the uppermost ear. The analysis of variance method (ANOVA), accordingly to the proposed by the Design III, was used on the analysis of the data and estimation of the variance components derived from the mathematical model, genetic variances, heritability and average degree of dominance for each of the studied characters. This estimatives were used on the simulation of 1000 data sets with similar characteristics to the real data analyzed. The ANOVA and restricted maximum likelihood (REML) methods were used on the prediction of the already mentioned parameters for each of the simulated data sets within each character. The 1000 estimatives obtained by each method, for each studied character, were used on the calculation of descriptive statistics (mean, standard deviation and relative accuracy) and for the ¯tting of box-plot graphics. Through the information obtained from the estimatives given by each method and in possession of the actual values that they should predict (values used in the simulation of the data sets) it was possible to compare both methods as to the e±ciency of the estimatives given by them. Both methods presented similar characteristics on the prediction of most of the variance components derived from the mathematical model, being that most di®erences were pertinent to the components related to the e®ects of progeny (¾2 p) and to the interactions between progeny and parental inbred (¾2 pt) and between progeny, parental inbred and environment (¾2 pta); which are the components of greater importance on the calculation of the genetic parameters. The ANOVA method was very e±cient on the prediction of ¾2 p, being that the smaller the reference value for this component, more the REML method approached the results obtained by the ANOVA method; for larger values of ¾2 pt the most e±cient was the REML method, but its e±ciency decayed and approached the ANOVA method for smaller reference values for this component. Both methods were poorly e±cient on the prediction of ¾2 pta, but the REML method was the least e±cient. The better performance of the ANOVA method on the prediction of the variance components of greater importance on the calculation of the genetic variances lead to a better performance of the ANOVA method on the prediction of all genetic parameters, with exception to the dominance variance, which depended solely on ¾2 pt. However, it was observed a tendency on the ANOVA method, in average, on the overestimation of the average degree of dominance of around 45% of the actual reference value, independently of the studied character.

The importance of cooperative relaying communication in substituting for, or complementing, multiantenna systems is described, and a brief literature review is presented. Amplify-and-forward (AF) and decode-and-forward (DF) relaying are investigated and compared for a dual-hop relay channel. The optimal strategy, source and relay optimal power allocation, and maximum cooperative gain are determined for the relay channel. It is shown that while DF relaying is preferable to AF relaying for strong source-relay links, AF relaying leads to more gain for strong source-destination or relay-destination links. Superimposed and selection AF relaying are investigated for multirelay, dual-hop relaying. Selection AF relaying is shown to be globally strictly outage suboptimal. A necessary condition for the selection AF outage optimality, and an upper bound on the probability of this optimality are obtained. A near-optimal power allocation scheme is derived for superimposed AF relaying. The maximum instantaneous rates, outage probabilities, and average capacities of multirelay, dual-hop relaying schemes are obtained for superimposed, selection, and orthogonal DF relaying, each with parallel channel cooperation (PCC) or repetition-based cooperation (RC). It is observed that the PCC over RC gain can be as much as 4 dB for the outage probabilities and 8.5 dB for the average capacities. Increasing the number of relays deteriorates the capacity performance of orthogonal relaying, but improves the performances of the other schemes. The application of rateless codes to DF relaying networks is studied by investigating three single-relay protocols, one of which is new, and three novel, low complexity multirelay protocols for dual-hop networks. The maximum rate and minimum energy per bit and per symbol are derived for the single-relay protocols under a peak power and an average power constraint. The long-term average rate and energy per bit, and relay-to-source usage ratio (RSUR), a new performance measure, are evaluated for the single-relay and multirelay protocols. The new single-relay protocol is the most energy efficient single-relay scheme in most cases. All the multirelay protocols exhibit near-optimal rate performances, but are vastly different in the RSUR. Several future research directions for fixed-rate and rateless coded cooperative systems, and frameworks for comparing these systems, are suggested.
Communications

Bones are multifunctional passive organs of movement that supports soft tissue and directly attached muscles. They also protect internal organs and are a reserve of calcium, phosphorus and magnesium. Each bone is covered with periosteum, and the adjacent bone surfaces are covered by articular cartilage. Histologically, the bone is an organ composed of many different tissues. The main component is bone tissue (cortical and spongy) composed of a set of bone cells and intercellular substance (mineral and organic), it also contains fat, hematopoietic (bone marrow) and cartilaginous tissue. Bones are a tissue that even in adult life retains the ability to change shape and structure depending on changes in their mechanical and hormonal environment, as well as self-renewal and repair capabilities. This process is called bone turnover. The basic processes of bone turnover are: • bone modeling (incessantly changes in bone shape during individual growth) following resorption and tissue formation at various locations (e.g. bone marrow formation) to increase mass and skeletal morphology. This process occurs in the bones of growing individuals and stops after reaching puberty • bone remodeling (processes involve in maintaining bone tissue by resorbing and replacing old bone tissue with new tissue in the same place, e.g. repairing micro fractures). It is a process involving the removal and internal remodeling of existing bone and is responsible for maintaining tissue mass and architecture of mature bones. Bone turnover is regulated by two types of transformation: • osteoclastogenesis, i.e. formation of cells responsible for bone resorption • osteoblastogenesis, i.e. formation of cells responsible for bone formation (bone matrix synthesis and mineralization) Bone maturity can be defined as the completion of basic structural development and mineralization leading to maximum mass and optimal mechanical strength. The highest rate of increase in pig bone mass is observed in the first twelve weeks after birth. This period of growth is considered crucial for optimizing the growth of the skeleton of pigs, because the degree of bone mineralization in later life stages (adulthood) depends largely on the amount of bone minerals accumulated in the early stages of their growth. The development of the technique allows to determine the condition of the skeletal system (or individual bones) in living animals by methods used in human medicine, or after their slaughter. For in vivo determination of bone properties, Abstract 10 double energy X-ray absorptiometry or computed tomography scanning techniques are used. Both methods allow the quantification of mineral content and bone mineral density. The most important property from a practical point of view is the bone’s bending strength, which is directly determined by the maximum bending force. The most important factors affecting bone strength are: • age (growth period), • gender and the associated hormonal balance, • genotype and modification of genes responsible for bone growth • chemical composition of the body (protein and fat content, and the proportion between these components), • physical activity and related bone load, • nutritional factors: – protein intake influencing synthesis of organic matrix of bone, – content of minerals in the feed (CA, P, Zn, Ca/P, Mg, Mn, Na, Cl, K, Cu ratio) influencing synthesis of the inorganic matrix of bone, – mineral/protein ratio in the diet (Ca/protein, P/protein, Zn/protein) – feed energy concentration, – energy source (content of saturated fatty acids - SFA, content of polyun saturated fatty acids - PUFA, in particular ALA, EPA, DPA, DHA), – feed additives, in particular: enzymes (e.g. phytase releasing of minerals bounded in phytin complexes), probiotics and prebiotics (e.g. inulin improving the function of the digestive tract by increasing absorption of nutrients), – vitamin content that regulate metabolism and biochemical changes occurring in bone tissue (e.g. vitamin D3, B6, C and K). This study was based on the results of research experiments from available literature, and studies on growing pigs carried out at the Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences. The tests were performed in total on 300 pigs of Duroc, Pietrain, Puławska breeds, line 990 and hybrids (Great White × Duroc, Great White × Landrace), PIC pigs, slaughtered at different body weight during the growth period from 15 to 130 kg. Bones for biomechanical tests were collected after slaughter from each pig. Their length, mass and volume were determined. Based on these measurements, the specific weight (density, g/cm3) was calculated. Then each bone was cut in the middle of the shaft and the outer and inner diameters were measured both horizontally and vertically. Based on these measurements, the following indicators were calculated: • cortical thickness, • cortical surface, • cortical index. Abstract 11 Bone strength was tested by a three-point bending test. The obtained data enabled the determination of: • bending force (the magnitude of the maximum force at which disintegration and disruption of bone structure occurs), • strength (the amount of maximum force needed to break/crack of bone), • stiffness (quotient of the force acting on the bone and the amount of displacement occurring under the influence of this force). Investigation of changes in physical and biomechanical features of bones during growth was performed on pigs of the synthetic 990 line growing from 15 to 130 kg body weight. The animals were slaughtered successively at a body weight of 15, 30, 40, 50, 70, 90, 110 and 130 kg. After slaughter, the following bones were separated from the right half-carcass: humerus, 3rd and 4th metatarsal bone, femur, tibia and fibula as well as 3rd and 4th metatarsal bone. The features of bones were determined using methods described in the methodology. Describing bone growth with the Gompertz equation, it was found that the earliest slowdown of bone growth curve was observed for metacarpal and metatarsal bones. This means that these bones matured the most quickly. The established data also indicate that the rib is the slowest maturing bone. The femur, humerus, tibia and fibula were between the values of these features for the metatarsal, metacarpal and rib bones. The rate of increase in bone mass and length differed significantly between the examined bones, but in all cases it was lower (coefficient b <1) than the growth rate of the whole body of the animal. The fastest growth rate was estimated for the rib mass (coefficient b = 0.93). Among the long bones, the humerus (coefficient b = 0.81) was characterized by the fastest rate of weight gain, however femur the smallest (coefficient b = 0.71). The lowest rate of bone mass increase was observed in the foot bones, with the metacarpal bones having a slightly higher value of coefficient b than the metatarsal bones (0.67 vs 0.62). The third bone had a lower growth rate than the fourth bone, regardless of whether they were metatarsal or metacarpal. The value of the bending force increased as the animals grew. Regardless of the growth point tested, the highest values were observed for the humerus, tibia and femur, smaller for the metatarsal and metacarpal bone, and the lowest for the fibula and rib. The rate of change in the value of this indicator increased at a similar rate as the body weight changes of the animals in the case of the fibula and the fourth metacarpal bone (b value = 0.98), and more slowly in the case of the metatarsal bone, the third metacarpal bone, and the tibia bone (values of the b ratio 0.81–0.85), and the slowest femur, humerus and rib (value of b = 0.60–0.66). Bone stiffness increased as animals grew. Regardless of the growth point tested, the highest values were observed for the humerus, tibia and femur, smaller for the metatarsal and metacarpal bone, and the lowest for the fibula and rib. Abstract 12 The rate of change in the value of this indicator changed at a faster rate than the increase in weight of pigs in the case of metacarpal and metatarsal bones (coefficient b = 1.01–1.22), slightly slower in the case of fibula (coefficient b = 0.92), definitely slower in the case of the tibia (b = 0.73), ribs (b = 0.66), femur (b = 0.59) and humerus (b = 0.50). Bone strength increased as animals grew. Regardless of the growth point tested, bone strength was as follows femur > tibia > humerus > 4 metacarpal> 3 metacarpal> 3 metatarsal > 4 metatarsal > rib> fibula. The rate of increase in strength of all examined bones was greater than the rate of weight gain of pigs (value of the coefficient b = 2.04–3.26). As the animals grew, the bone density increased. However, the growth rate of this indicator for the majority of bones was slower than the rate of weight gain (the value of the coefficient b ranged from 0.37 – humerus to 0.84 – fibula). The exception was the rib, whose density increased at a similar pace increasing the body weight of animals (value of the coefficient b = 0.97). The study on the influence of the breed and the feeding intensity on bone characteristics (physical and biomechanical) was performed on pigs of the breeds Duroc, Pietrain, and synthetic 990 during a growth period of 15 to 70 kg body weight. Animals were fed ad libitum or dosed system. After slaughter at a body weight of 70 kg, three bones were taken from the right half-carcass: femur, three metatarsal, and three metacarpal and subjected to the determinations described in the methodology. The weight of bones of animals fed aa libitum was significantly lower than in pigs fed restrictively All bones of Duroc breed were significantly heavier and longer than Pietrain and 990 pig bones. The average values of bending force for the examined bones took the following order: III metatarsal bone (63.5 kg) <III metacarpal bone (77.9 kg) <femur (271.5 kg). The feeding system and breed of pigs had no significant effect on the value of this indicator. The average values of the bones strength took the following order: III metatarsal bone (92.6 kg) <III metacarpal (107.2 kg) <femur (353.1 kg). Feeding intensity and breed of animals had no significant effect on the value of this feature of the bones tested. The average bone density took the following order: femur (1.23 g/cm3) <III metatarsal bone (1.26 g/cm3) <III metacarpal bone (1.34 g / cm3). The density of bones of animals fed aa libitum was higher (P<0.01) than in animals fed with a dosing system. The density of examined bones within the breeds took the following order: Pietrain race> line 990> Duroc race. The differences between the “extreme” breeds were: 7.2% (III metatarsal bone), 8.3% (III metacarpal bone), 8.4% (femur). Abstract 13 The average bone stiffness took the following order: III metatarsal bone (35.1 kg/mm) <III metacarpus (41.5 kg/mm) <femur (60.5 kg/mm). This indicator did not differ between the groups of pigs fed at different intensity, except for the metacarpal bone, which was more stiffer in pigs fed aa libitum (P<0.05). The femur of animals fed ad libitum showed a tendency (P<0.09) to be more stiffer and a force of 4.5 kg required for its displacement by 1 mm. Breed differences in stiffness were found for the femur (P <0.05) and III metacarpal bone (P <0.05). For femur, the highest value of this indicator was found in Pietrain pigs (64.5 kg/mm), lower in pigs of 990 line (61.6 kg/mm) and the lowest in Duroc pigs (55.3 kg/mm). In turn, the 3rd metacarpal bone of Duroc and Pietrain pigs had similar stiffness (39.0 and 40.0 kg/mm respectively) and was smaller than that of line 990 pigs (45.4 kg/mm). The thickness of the cortical bone layer took the following order: III metatarsal bone (2.25 mm) <III metacarpal bone (2.41 mm) <femur (5.12 mm). The feeding system did not affect this indicator. Breed differences (P <0.05) for this trait were found only for the femur bone: Duroc (5.42 mm)> line 990 (5.13 mm)> Pietrain (4.81 mm). The cross sectional area of the examined bones was arranged in the following order: III metatarsal bone (84 mm2) <III metacarpal bone (90 mm2) <femur (286 mm2). The feeding system had no effect on the value of this bone trait, with the exception of the femur, which in animals fed the dosing system was 4.7% higher (P<0.05) than in pigs fed ad libitum. Breed differences (P<0.01) in the coross sectional area were found only in femur and III metatarsal bone. The value of this indicator was the highest in Duroc pigs, lower in 990 animals and the lowest in Pietrain pigs. The cortical index of individual bones was in the following order: III metatarsal bone (31.86) <III metacarpal bone (33.86) <femur (44.75). However, its value did not significantly depend on the intensity of feeding or the breed of pigs.

The object of research is the territory of the city of Lviv (Ukraine). Lviv (geographical coordinates: 49N50, 24E00) is the largest city in Western Ukraine, with a population of over 720,000 inhabitants. The city is located in the western part of the Volyn-Podilska Upland, on the line of the Main European Ridge of the Baltic and Black Sea basins. Subject of research is relief parameters (maximum, average and minimum heights, vertical dismemberment and steepness of the surface) and land use characteristics (building intensity, phytocenotic cover). The purpose of research is to study the features of the territory of Lviv from the standpoint of influence on the hydrological regime and erosion processes. Methodology. Peculiarities of the territory of Lviv were studied by processing topographic maps using aerial photography materials and route surveys. Morphometric analysis of the relief was performed on topographic maps of scale 1: 10000 by dividing the map into elementary squares with an area of 0.25 km2. The research covers an area of 100.25 km2 (401 elementary squares). Within the elementary squares, the maximum, average and minimum heights of the territory, the depth of local erosion bases, the average surface steepness, the intensity and nature of construction, and the features of vegetation were determined. Results. The territory of Lviv is characterized by a variety of relief conditions and related nature of surface use. On the basis of morphometric maps of maximum and minimum heights, vertical dismemberment and steepness of the surface, we can distinguish the flat peripheral part of the city and the middle band of elevations. The asymmetry of the territory of Lviv in relation to the watershed causes various potential dangers of erosion processes and related unproductive moisture losses. The intensity of construction increases from the periphery to the center, with the exception of modern multi-storey buildings of the Sykhiv massif and industrial areas in the western part of the city. Low specific weight of waterproof coatings is characterized by the eastern and northern parts of the city with a complex relief. The largest amount of greenery is concentrated in the eastern part of the city (Vysokyi Zamok Park, Shevchenkivskyi grove, Pohulyanka Forest Park, Lychakiv), where surfaces with maximum relative heights predominate. The great variety of the underlying surface on the territory of Lviv causes different conditions for the formation of surface runoff and associated unproductive moisture consumption. The high potential danger of erosion processes is primarily noted by the structural-denudation level of Roztochia, which is characterized by the highest values of surface steepness. Complex relief conditions, intensive anthropogenic impact determine the need for anti-erosion organization of the city and measures aimed at optimizing hydrological processes. Scientific novelty. One of the criteria that characterizes the degree of landscape transformation within the city is the intensity of construction, which is determined by the proportion of watertight areas in the overall balance of the territory. Peculiarities of spatial arrangement of elementary plots with different intensity of construction in combination with relief parameters and land use scheme are determined. Practical significance. Knowing the parameters of the terrain and the peculiarities of land use, it is possible to determine the potential intensity of erosion processes in the territory of Lviv, to assess the level of anthropogenic changes in the hydrological regime.

In this work, carbon dots (CDs), obtained through microwave assisted synthesis from butane tetra carboxylic acid (BTCA), was introduced into chitosan film via simple solvent casting approach. The CDs had an average diameter of 40 to 60 nm as determined by Transmission Electron Microscopy (TEM) analysis. They possessed a zeta potential of −20.2 mV. The X-ray photon spectroscopy (XPS) confirmed presence of carboxylate groups on the surface of carbon dots. The XRD of both the plain sample Ch/CD (0) and carbon dots loaded sample Ch/CD(2) showed two crystalline sharp peaks at 14.6 and 18.1 degree, along with presence of amorphous region also. The moisture absorption data was well fitted on GAB isotherm and the profiles obtained were sigmoidal. The water vapor permeation rates for the sample Ch/CD(0) and Ch/CD(2) were found to be 1758 and 956 g/m2 /day respectively. The film samples Ch/CD(0) and Ch/CD(20 expanded 2.8 and 103 times when immersed in 4% gelatin solution for 4 h. The % hemolysis for the samples Ch/CD(0) and Ch/CD(2) was 2.12 and 1.11 respectively, thus indicating biocompatible nature of the films. In the ex-vivo mucoadhesion study, the maximum detachment force (Fmax) was 88.22 and 46.28 mN for the samples Ch/CD(0) and Ch/CD(2) respectively. Finally, both of the samples, namely Ch/CD (0) and Ch/CD(2) scored “0”, suggesting their non-cell cytotoxic nature.

Beneath the gently rolling, seemingly mundane topography that characterizes the shortgrass steppe is a complex mosaic of soils. Many of these soils are superimposed upon older, buried soils that formed in other millennia under different climatic regimes. The nature of this soil mosaic reveals much about the past and dictates much about the future of the shortgrass steppe. There is considerable heterogeneity among soils of the shortgrass steppe, yet they maintain a high degree of homogeneity when contrasted with soils of other ecosystems. The driving forces that make these soils alike are a semiarid climate and a resilient plant community ( P ielke and Doesken, chapter 2, this volume; and Lauenroth, chapter 5, this volume). The combined effects of vegetation and climate on soil development yield generally predictable results. Shortgrass steppe soils are characterized by the accumulation of organic matter in the surface (0–20 cm). Approximately 60% of the graminoid root mass resides in the - rst 10 cm of mineral soil (Schimel et al., 1986); 90% is contained in the surface 20 cm (Schimel et al., 1985). Surface horizons typically are darker hued than underlying horizons and have organic carbon contents that average 1% to 3% (Yonker et al., 1988). Shortgrass steppe soils maintain a high-percent base saturation (and high pH) because of low leaching and weathering potentials that result from semiarid conditions. Zones of secondary calcium carbonate accumulation are common in subsurface horizons and may appear as threads, seams, or nodules (Blecker et al., 1997). In addition, these soils are characterized by zones of secondary clay accumulation in subsurface horizons; clay accumulations are a result of either the in situ weathering of primary minerals or the translocation of clay minerals leached from the surface horizon. In either case, the maximum depth of accumulation gives some indication of the time-averaged depth of the wetting front in the soil pro- le (Blecker et al., 1997). The factors that produce considerable heterogeneity among the soils of the shortgrass steppe are related to parent material, the age of the soil, and the subtleties of topography. These factors vary at a - ner scale than either vegetation or climate.

ABSTRACT The ~11-km-wide, Paleoproterozoic Dhala impact structure in north-central India comprises voluminous exposures of impact melt breccia. These outcrops are discontinuously spread over a length of ~6 km in a semicircular pattern along the northern, inner limit of the monomict breccia ring around the central elevated area. This study of the magnetic fabrics of impact breccias and target rocks from the Dhala impact structure identified a weak preferred magnetic orientation for pre-impact crystalline target rocks. The pre- and synimpact rocks from Dhala have magnetite and ilmenite as common magnetic phases. The distributions of magnetic vectors are random for most impact melt breccia samples, but some do indicate a preferred orientation. Our anisotropy of magnetic susceptibility (AMS) data demonstrate that the shape of susceptibility ellipsoids for the target rocks varies from prolate to oblate, and most impact melt breccia samples display both shapes, with a slight bias toward the oblate geometry. The average value for the corrected degree of anisotropy of impact melt rock (P′ = 1.009) is lower than that for the target rocks (P′ = 1.091). The present study also shows that both impact melt breccia and target rock samples of the Dhala structure have undergone minor postimpact alteration, and have similar compositions in terms of magnetic phases and high viscosity. Fine-grained iron oxide or hydroxide is the main alteration phase in impact melt rocks. Impact melt rocks gave a narrow range of mean magnetic susceptibility (Km) and P′ values, in contrast to the target rock samples, which gave Km = 0.05–12.9 × 10−3 standard international units (SI) and P′ = 1.036–1.283. This suggests similar viscosity of the source magma, and limited difference in the degrees of recorded deformation. Between Pagra and Maniar villages, the Km value of impact melt breccias gradually decreases in a clockwise direction, with a maximum value observed near Pagra (Km = 1.67 × 10−3 SI). The poor grouping of magnetic fabrics for most impact melt rock samples implies local turbulence in rapidly cooled impact melt at the front of the melt flow immediately after the impact. The mean K1 for most impact melt samples suggests subhorizontal (&lt;5°) flow in various directions. The average value of Km for the target rocks (4.41 × 10−3 SI) is much higher compared to the value for melt breccias (1.09 × 10−3 SI). The results of this study suggest that the melt breccias were likely part of a sheet-like body of sizeable extent. Our magnetic fabric data are also supported by earlier core drilling information from ~70 locations, with coring depths reaching to −500 m. Our extensive field observations combined with available widespread subsurface data imply that the impact melt sheet could have covered as much as 12 km2 in the Dhala structure, with an estimated minimum melt volume of ~2.4 km3.

This chapter aimed to estimate speech perception benefits in quiet for clients with different degrees of hearing loss. The difference between aided and unaided scores on a monosyllabic word test presented binaurally was used as the measure of benefit. Retrospective data for 492 hearing aid users with four-frequency pure-tone average hearing losses (PTA) ranging from 5 dB HL to 76 dB HL in the better ear were analyzed using nonlinear regression. The mean benefit for the perception of monosyllabic words in this group of clients was 22.3% and the maximum expected benefit was 33.6% for a PTA of 52 dB HL. The expected benefit can be expressed as a reduction of the error rate by about half for isolated words and about one quarter for sentences across the full range of PTA.

Earth is the largest of the four terrestrial planets, three of which have substantial atmospheres. The astronomical and orbital parameters are summarized in table 9.1. Our planet has an obliquity of 23.5°, giving rise to well-known seasonal variations in solar insolation. The orbital elements are slightly perturbed by other planets in the solar system (primarily Jupiter), with time scales from 20 to 100 kyr, and these changes are believed to cause the advance and retreat of ice sheets. The last glacial maximum (LGM) occurred 18 kyr ago, at which time the planet was colder by several degrees centigrade on average. At present Earth is in an interglacial warm period. The origin of Earth may not be very different from that of the other terrestrial bodies. However, three properties may be unique to this planet. One is the formation of the Moon, probably via collision between Earth and a Mars-sized body. Second is the release of a huge amount of water from the interior (see discussion in section 8.5). Third, Earth is endowed with a large magnetic field that protects it from direct impact by the solar wind. Seventy percent of Earth's surface is covered by oceans, which have a mean depth of 3 km. There is so much water that Arthur C. Clarke proposed that "Ocean" might be a better name for our planet than "Earth." The enormous body of water became the cradle of life as early as 3.85 Gyr ago. The present terrestrial environment is the end-product of billions of years of evolution driven by the hydrological cycle and global biogeochemical cycles, in addition to the slower forces of geodynamics and geochemistry. The massive hydrological cycle and the biogeochemical cycles that operate on Earth are absent from other planets in the solar system. Mars in the remote past might have had a milder climate with liquid water on the surface, but the planet dried up a few eons ago. There is to date no observational evidence for the hypothetical oceans (composed of liquid hydrocarbons) on Titan. Life on a planetary scale equivalent to the terrestrial biosphere does not exist elsewhere in the solar system.

Analysis of 35 years observed trends in summertime daily maximum and minimum temperatures in two non attainment California air basins showed coastal cooling and inland warming. To study the impact of these results on the energy consumption we analyzed the cooling/heating degree days (CDD/HDD) of California long term observed temperatures. In this research historical surface 2-m air temperature data analyses consist of long-term data records, from 273 locations in California, and the primary sources of such data include the cooperative network, first order National Weather Service stations, and military weather stations. Data were used from 273 cooperative stations with more than 100 stations in the northern Central Valley (CV) of California, each with 40 to 60 years of monthly average, minimum, and maximum temperature data records. About 100 of the stations are in the San Francisco Bay (SFB) and 30 of the stations are on the South Coast Air Basin (SoCAB) of California. Analysis of the CDD/HDD has been undertaken for California in general and in the SFB and SoCAB in particular, under regional climate change conditions. Regional climate fluctuations have larger effects on surface temperatures, which in turn affect the CDD and HDD. A closer look to the CDD reflects an asymmetric increase between the coast and inland regions of California during the last 35 years. In general coastal areas experienced historical decrease of CDD while inland regions experienced increase in CDD. This is attributed to the sea breeze flows, which suggest an increase of the cold marine air intrusion due to the increase of the regional sea breeze potential, which naturally ventilates the coastal areas.

Most engineering surfaces possess topographies that are anisotropic. Some of the anisotropic surfaces are unintended result of machining process and others are by design for the purpose of lubricant retention or other considerations. Such is the case in problems involving piston liner and mechanical seal performance wherein the conformal contact of two rough surfaces is considered. It becomes critical to component performance to predict average contact pressure and gap between rough surfaces. Two of the well-known asperity-based statistical theories along with a deterministic method, based on Multi Level Multi Summation (MLMS) technique, are used to study the contact of nominally flat rough surfaces. The asperity-based statistical theories are GW model (Greenwood and Williamson, [1]), and its extension proposed by Chang, Bogy and Etsion [2], CEB model, for treating elastic-plastic contact. The contact examined is a set of nominally flat rough surfaces with a smooth flat. This study attempts to address two questions. The first concerns the effectiveness of asperity-based statistical theories in predicting average contact stress of rough surfaces with various degrees of topographic anisotropy. The second question involves the use of directional curvatures to ascertain the appropriateness of plane curvatures when degree of anisotropy is significant. To this end random surfaces are generated for five degrees of anisotropy including correlation length ratios 1, corresponding to an isotropic surface, and 3, 9, 36 and 81, corresponding to an increasing degree of geometric anisotropy. A module of Surface Distress Analytical Toolset (SDAT), for treating dry contact using deterministic approach with MLMS technique, is utilized to compute the contact pressure for these surfaces. This analysis constitutes ten surfaces for each correlation ratio resulting in fifty simulations of SDAT. For each correlation ratio statistical averages and variations of the maximum and mean contact pressures are found. Using the generated random surfaces, GW and CEB models are furnished with the parameters that include the standard deviation of summit height distribution, area summit density and six curvatures associated with asperity summit. These involve four directional curvatures that include curvatures along the x, y, positive diagonal, negative diagonal, and two equivalent curvatures, one based on spherical tip using average of the four diagonal curvatures and the other based on ellipsoidal asperity summit (Fig 1). The study suggests that GW and CEB typically overestimate average contact pressure. The mean pressures predicted using the largest directional summit curvature agrees most favorably with those predicted by SDAT. Surprisingly, agreement is most favorable for highest geometrical anisotropy. Both statistical methods seem effective in predicting mean gap between surfaces for moderate to low nominal pressures.

Construction industry can be affected by climate change in particular temperature and temperature extremes not only for the design phase but also for production or end-use/operation phases. In this regard the major climatic factors that are dominant for the building lifecycle must be evaluated. This study determined the 13-sector specific ET-SCI temperature indices annually and investigated their trend characteristics at Edirne, Kırklareli and Tekirdağ of Thrace Region for the historical period. The results showed a dominant increasing temperature trend over the region. Edirne, Kırklareli, and Tekirdağ stations showed significantly increasing trends for the hottest night, average daily maximum, and average daily minimum temperature indices in this study. Furthermore, the hottest day index also showed an increasing trend for all the stations with a significant trend for Edirne and Tekirdağ. Moreover, significant decreasing trends were observed in the heating degree days and increasing significant trends were observed for the SU (summer days), CDDCOLD18 (cooling degree days) and TR (tropical nights) values at all the stations.

In the area of black-box identication, NARMAX models are of great interest. The main diculty faced when working with such models is the selection of the correct structure to represent the underlying system in the data. Orthogonal Least Squares (OLS) methods are widely used for this task, however, there are systems with a high degree of non-linearity and long term dependencies, which makes the use of traditional OLS methods computationally impracticable. In this sense, this paper studies the use of Multi-Gene Genetic Programing (MGGP) together with the traditional OLS method to increase the search space and turn the structure selection practicable for average performance computer. It is shown that, in real-life problem data, the algorithm can nd better models than previous works' models. The MGGP found a model for a hydraulic pumping system with a better one-step-ahead prediction error (0:058 mlc2 against 0:070 mlc2) using PEM technique and better free-run simulation error (0:997 mlc2 against 1:120 mlc2) using SEM technique. The MGGP found a model with such a degree of non-linearity and maximum input-output lags that totalizes 142505 candidate terms for traditional OLS analysis, which is impracticable for average performance computers.

To achieve higher efficiency target of the advanced turbine systems, the closed-loop steam cooling scheme is employed to cool the airfoil. It is proven from the experimental results at laboratory working conditions that injecting mist into steam can significantly augment the heat transfer in the turbine blades with several fundamental studies. The mist cooling technique has to be tested at gas turbine working conditions before implementation. Realizing the fact that conducting experiment at gas turbine working condition would be expensive and time consuming, the computational simulation is performed to get a preliminary evaluation on the potential success of mist cooling at gas turbine working conditions. The present investigation aims at validating a CFD model against experimental results in a 180-degree tube bend and applying the model to predict the mist/steam cooling performance at gas turbine working conditions. The results show that the CFD model can predict the wall temperature within 8% of experimental steam-only flow and 16% of mist/steam flow condition. Five turbulence models have been employed and their results are compared. Inclusion of radiation into CFD model causes noticeable increase in accuracy of prediction. The reflect Discrete Phase Model (DPM) wall boundary condition predicts better than the wall-film boundary condition. The CFD simulation identifies that mist impingement over outer wall is the cause for maximum mist cooling enhancement at 45° of bend portion. The computed results also reveals the phenomenon of mist secondary flow interaction at bend portion, adding the mist cooling enhancement at the inner wall. The validated CFD simulation predicts that average of 100% mist cooling enhancement can be achieved by injecting 5% mist at elevated GT working condition.

Abstract Sub-sea vertical Xmas tree is one of the key equipment in the oil industry. Erosion caused by particles in the flow of oil and gas may lead to equipment failure or even interruption of oil exploitation. Therefore, it is important to figure out the characteristics of erosion in vertical Xmas tree. In the present work, the AISI 8630 erosion model and the Forder wall rebound model has been applied to study the erosion of production channel and choke valve in the tree. The maximum and average surface erosion amount are introduced to evaluate the erosion degree. The results show that for the production channel, erosion mainly occurs in the interior of the turning point of the channel and the interior of the downstream wall near the joint, and the most serious eroded area is located at the bottom of the downstream wall of the channel. Comparing the effects of blind pipe length, particle concentration, particle size and flow velocity on the erosion wear of the production channel, it is found that the flow velocity is the main factor affecting erosion. As the velocity of fluid increases, the maximum and the average surface erosion on the inner wall of production channel increase in a steep manner. For the choke valve, as the relative opening increases, the maximum erosion amount decreases sharply. However, compared with the production channel, the wear of the valve channel is much more serious, and more attention should be paid in industrial operations.

Film cooling is one of the preferred methods for effective cooling of a gas turbine that forms a protective layer between hot flue gases and blade surface. This paper investigates the interaction of mist in the secondary flow and physics indicating the upper limit of mist concentration. Numerical simulations are performed on a flat plate having a series of discrete holes with 35 degree streamwise orientation and the holes are connected to a common delivery plenum chamber. The blowing ratio, density ratio and Reynolds number based on freestream and hole diameter (D) are 0.5, 1.2 and 15885 respectively. A two-phase mist consisting of finely dispersed water droplets of 10 micron in an airstream is introduced as the coolant from these holes. The latent heat absorbed by the evaporating droplets significantly reduces the sensible heat of the main stream, providing heat sinks that result in enhanced cooling effectiveness. The coupling between the two-phases is modelled through the interaction terms in the transport equations. Computations are performed by ANSYS Fluent 15.0 using k-ε realizable model. The results illustrate insight of complex transport phenomena associated with the mist of varying concentration from 2% to 7%. It has been observed that the maximum enhancement of cooling effectiveness reaches 43% at X/D = 10 for 2% mist by mass with an average enhancement of 26.5%. For 3% mist, the maximum enhancement becomes 80% at X/D = 16 with the average cooling enhancement of 43%. Mist concentrations 5% and beyond trend to increase average cooling because of more absorption of latent heat by droplets, but its trajectories shift towards wall, detrimental to the blade due to corrosion effect and thermal stresses.

An MR thermometry technique with sub-degree celsius accuracy is needed to measure in vivo temperatures vs. time in porcine brains at ultra-high fields. Porcine models are used to study thermoregulatory temperature response of the ultra-high field radiofrequency (RF) heating. The porcine hot critical temperature limit is comparable to and lower than that of humans. Also, porcine thermoregulatory mechanisms are similar to humans. Thus, conservative porcine thermoregulatory temperature responses can help develop new RF safety thresholds for ultra-high field human MRI. Sub-degree C temperature accuracy is needed since RF safety guidelines limit the maximum in vivo head temperature change due to RF heating to 1 °C over the core body temperature. Three-dimensional temperature maps over time are required since non-uniform RF power deposition at ultra-high fields and blood flow produce non-uniform in vivo temperatures with local hot spots. Thermogenic hazards are related to in vivo temperatures and temperature-time history — and not to the typically measured whole head average specific absorption rate.