Residual closeness for helm and sunflower graphs

Vulnerability is an important concept in network analysis related with the ability of the network to avoid intentional attacks or disruption when a failure is produced in some of its components. Often enough, the network is modeled as an undirected and unweighted graph in which vertices represent the processing elements and edges represent the communication channel between them. Different measures for graph vulnerability have been introduced so far to study different aspects of the graph behavior after removal of vertices or links such as connectivity, toughness, scattering number, binding number and integrity. In this paper, we consider residual closeness which is a new characteristic for graph vulnerability. Residual closeness is a more sensitive vulnerability measure than the other measures of vulnerability. We obtain exact values for closeness, vertex residual closeness (VRC) and normalized vertex residual closeness (NVRC) for some wheel related graphs namely helm and sunflower.Publisher's Versio

Solution to an open problem on the closeness of graphs

A network can be analyzed by means of many graph theoretical parameters. In the context of networks analysis, closeness is a structural metric that evaluates a node's significance inside a network. A cactus is a connected graph in which any block is either a cut edge or a cycle. This paper analyzes the closeness of cacti, we determine the unique graph that minimizes the closeness over all cacti with fixed numbers of vertices and cycles, which solves an open problem proposed by Poklukar \& \v{Z}erovnik [Fundam. Inform. 167 (2019) 219--234]

Closeness and Residual Closeness of Harary Graphs

Analysis of a network in terms of vulnerability is one of the most significant problems. Graph theory serves as a valuable tool for solving complex network problems, and there exist numerous graph-theoretic parameters to analyze the system's stability. Among these parameters, the closeness parameter stands out as one of the most commonly used vulnerability metric. Its definition has evolved over time to enhance ease of formulation and applicability to disconnected structures. Furthermore, based on the closeness parameter, residual closeness, which is a newer and more sensitive parameter compared to other existing parameters, has been introduced as a new graph vulnerability index by Dangalchev. In this study, the outcomes of the closeness and residual closeness parameters in Harary Graphs have been examined. Harary Graphs are well-known constructs that are distinguished by having $n$ vertices that are $k$-connected with the least possible number of edges.Comment: 21 pages preprin

Statistical analyses of artificial waterpoints: their effect on the herbaceous and woody structure composition within the Kruger National Park

The objective of this project is to link the statistical theory used in the ecological sciences with an actual project that was developed for the South African National Parks Scientific Services. It investigates the changes that have occurred in the herbaceous and woody structure due to the closure of artificial waterpoints; including the impacts that elephants and other herbivores have on the vegetation of the Kruger National Park. This project was designed in conjunction with South African National Parks (SANP) Scientific Services and it is a registered project with this department. The results of this project will be submitted to Scientific Services in accordance with the terms and conditions of a SANP research project. A major concern within the KNP is the declining numbers of rare antelope and numerous projects have been developed to investigate possible ways of halting this decline and thus protecting the heterogeneity of the Kruger National Park. Three different datasets were investigated, covering three aspects of vegetation structure and composition within the KNP. The first investigated the changes that have occurred since the N'washitsumbe enclosure in the Far Northern KNP was fenced off from the rest of the park. The results show that over the 40 years since the enclosure was built, changes have occurred which have resulted in a significant difference in the abundance of Increaser 2 and Decreaser grass species between the inside and the outside of the enclosure. Increaser 2 and Decreaser categories are the result of a grass species classification depending on whether the species thrives or is depressed by heavy grazing. The difference in grass species composition and structure between the inside and the outside of the enclosure indicates that the grazing animals within the KNP have influenced the grass composition in a way that favours the dominant animals. This has resulted in a declining roan antelope population - one of the species that is considered as a 'rare antelope'. Many artificial waterpoints (boreholes and dams) have also been closed throughout the KNP in the hope of resulting in a change in vegetation structure and composition in favour of the roan. Veld condition assessment data for 87 boreholes throughout the Park was analyzed to determine whether the veld in the vicinity is beginning to change towards a more Decreaser dominated sward which would favour the roan. The results were analyzed for the different regions of the Park; and they indicate that changes are becoming evident; however, the results are not particularly conclusive, yet. The majority of the boreholes were closed between 1994 and 1998 which means that not a lot of data were available to be analyzed. A similar study conducted in another 10 years time might reveal more meaningful results. However the results are moving in the direction hoped for by the management of the KNP. The results show that the grass composition has a higher proportion of Decreaser grasses since the closure of the waterpoints, and the grass biomass around these areas has also improved. The results were analyzed on an individual basis; and then on a regional basis as the minimal data meant that the individual analyses did not provide any significant results. A third study was then done on the impact that the rapidly increasing elephant population on the vegetation within the Riparian zone along three rivers in the Far Northern region of the KNP. The riparian zone is an important part of the landscape, in terms of providing food for many animals as well as shade. The elephant population has increased substantially since the termination of the culling program and this means that the feeding requirements of the population has increased which could result in severe damage upon the vegetation, as elephants can be very destructive feeders. The results show surprising differences between the three years of data that were analyzed; however the results indicate that the elephants are targeting specific height ranges of trees when feeding; however they do not seem to consistently target specific tree species. This is positive for the diversity of the Riparian zone as this region is very important both ecologically and aesthetically for the tourists who visit the Park

Symmetry in Graph Theory

This book contains the successful invited submissions to a Special Issue of Symmetry on the subject of ""Graph Theory"". Although symmetry has always played an important role in Graph Theory, in recent years, this role has increased significantly in several branches of this field, including but not limited to Gromov hyperbolic graphs, the metric dimension of graphs, domination theory, and topological indices. This Special Issue includes contributions addressing new results on these topics, both from a theoretical and an applied point of view

Training of Template-Specific Weighted Energy Function for Sequence-to-Structure Alignment

Threading is a protein structure prediction method that uses a library of template protein structures in the following steps: first the target sequence is matched to the template library and the best template structure is selected, secondly the predicted target structure of the target sequence is modeled by this selected template structure. The deceleration of new folds which are added to the protein data bank promises completion of the template structure library. This thesis uses a new set of template-specific weights to improve the energy function for sequence-to-structure alignment in the template selection step of the threading process. The weights are estimated using least squares methods with the quality of the modelling step in the threading process as the label. These new weights show an average 12.74% improvement in estimating the label. Further family analysis show a correlation between the performance of the new weights to the number of seeds in pFam

Mekanik malzeme modeli ve ilgili parametrelerin kestirilmesi için yumuşak biyolojik dokular üstünde yapılan yerinde indentör deneyleri.

Soft biological tissues, being live and due to their physiological structures, display considerably complex mechanical behaviors. For a better understanding and use in various applications, first study to be carried out is the tests made particularly as in vivo. An indenter test device developed for this purpose in the METU, Department of Mechanical Engineering, Biomechanics Laboratory is operational. In this study, in order to carry out precise and dependable tests, initially, various tests and improvements were conducted on the device and the software controlling the device. At the end of this study, displacement and load measurement accuracies and precisions were improved. Better algorithms for filtering the noisy data were prepared. Some test protocols within the software were improved and new protocols were annexed. To be able to conduct more dependable tests a new connection system was attached to the device. In order to study the anisotropic behavior of soft tissues ellipsoid tips were designed and produced. In the second phase of the study, tests on medial forearm were carried out. In these tests, hysteresis, relaxation and creep behaviors displaying the viscoelastic v properties of the soft biological tissues were observed. In addition to viscoelastic behaviors, preconditioning (Mullin’s) effect and anisotropic response were examined. By using the results of the relaxation and creep tests, parameters of the Prony series capable of modelling these data were determined. With this study, some important conclusions regarding the soft biological tissues were drawn and thus the behaviors of the soft biological tissues were better understood. Besides, the difficulties inherent to in-vivo tests were recognized and actions to reduce these difficulties were explained. Finally, clean experimental data, to be used in the computer simulations, were obtained.M.S. - Master of Scienc

Selenium in soils of the Lower Wasatch Formation, Campbell County, Wyoming: Geochemistry, distribution, and environmental hazards

The author has identified the following significant results. Seleniferous Shingle series soils and sandstone outcrops of section 27, T 48 N, R 71 W, Wyoming are mapped on aerial photography by their association with Astragalus bisulcatus. Chemical leachate analyses and atomic absorption methods reveal all studied Samsil and Shingle soils to contain acid, base, and water soluble selenium compounds, and that water extractions showed varied concentration behavior due to soil pH. Acid-soluble selenium is found to be associated with smectite. Statistical analyses confirm that A. bisulcatus presence has a weak influence on soil-lens organic selenium concentration, and determine the importance of other geobotanical factors for convertor presence. Environmental procedures of high selenium lens burial, convertor plant eradication, and revegetated site monitoring are recommended. Usage of density analysis and photographic enlargement are used to successfully produce both a control area and a Campbell County, Wyoming regional map of A. bisulcatus supportive soils and outcrops using Skylab photography

Complexity in Economic and Social Systems

There is no term that better describes the essential features of human society than complexity. On various levels, from the decision-making processes of individuals, through to the interactions between individuals leading to the spontaneous formation of groups and social hierarchies, up to the collective, herding processes that reshape whole societies, all these features share the property of irreducibility, i.e., they require a holistic, multi-level approach formed by researchers from different disciplines. This Special Issue aims to collect research studies that, by exploiting the latest advances in physics, economics, complex networks, and data science, make a step towards understanding these economic and social systems. The majority of submissions are devoted to financial market analysis and modeling, including the stock and cryptocurrency markets in the COVID-19 pandemic, systemic risk quantification and control, wealth condensation, the innovation-related performance of companies, and more. Looking more at societies, there are papers that deal with regional development, land speculation, and the-fake news-fighting strategies, the issues which are of central interest in contemporary society. On top of this, one of the contributions proposes a new, improved complexity measure

Family Resemblance: A Study of Linguistic Conformity within Family Systems

This thesis reports the results of an empirical study designed to test two hypotheses from the early psychiatric work of C. G. Jung: first, the existence of a family disposition toward the word association test (WAT), and second, the theory that there is interference between the thinking and the feeling functions in an individual\u27s cognitive processing. The experiment involved 52 normal subjects from 15 families, ranging in age from 12 to 65. Subjects were tested using an association instrument adapted from the WAT developed by Jung (Jung, 1973). Response commonalty was examined along several dimensions: identical verbal response, identical category response, and identical reaction type. Subjects were found to have 20% verbal commonalty and 34-38% categorical commonalty within family units. Comparison of relatives responses to those of non-related individuals using a Spearman rank order correlation test on classified responses, yielded an average correlation figure of .29 for related and .25 for unrelated pairs of individuals; this difference seemed too small to support the hypothesis, but no formal test of significance was performed. Sample size proved to small to test the significant of response pattern redundancy within families. In the second part of the experiment, 38 subjects completed he deductive logic section of the Ross Test of Higher Cognitive Processes, and their error rate was compared with their rate of predicative responses on the WAT. A Pearson Product Moment Correlation was .57, indicating a moderately strong correlation between preference for predication, a characteristic of the feeling function, and difficulty with deductive logic, a process of ;the thinking function. A theoretical chapter traces the evolution of Jung\u27s cognitive theories from his early word association experiments (Jung, 1973) to the development of his functional system of psychological typology (June, l971). 37 tables, 12 figures