Low-Complexity Energy-Efficient Broadcasting in One-Dimensional Wireless Networks

In this paper, we investigate the transmission range assignment for N wireless nodes located on a line (a linear wireless network) for broadcasting data from one specific node to all the nodes in the network with minimum energy. Our goal is to find a solution that has low complexity and yet performs close to optimal. We propose an algorithm for finding the optimal assignment (which results in the minimum energy consumption) with complexity O(N^2). An approximation algorithm with complexity O(N) is also proposed. It is shown that, for networks with uniformly distributed nodes, the linear-time approximate solution obtained by this algorithm on average performs practically identical to the optimal assignment. Both the optimal and the suboptimal algorithms require the full knowledge of the network topology and are thus centralized. We also propose a distributed algorithm of negligible complexity, i.e., with complexity O(1), which only requires the knowledge of the adjacent neighbors at each wireless node. Our simulations demonstrate that the distributed solution on average performs almost as good as the optimal one for networks with uniformly distributed nodes.Comment: 17 page

A Branch-and-Price Algorithm for Bin Packing Problem

Bin Packing Problem examines the minimum number of identical bins needed to pack a set of items of various sizes. Employing branch-and-bound and column generation usually requires designation of the problem-specific branching rules compatible with the nature of the pricing sub-problem of column generation, or alternatively it requires determination of the k-best solutions of knapsack problem at level kth of the tree. Instead, we present a new approach to deal with the pricing sub-problem of column generation which handles two-dimensional knapsack problems. Furthermore, a set of new upper bounds for Bin Packing Problem is introduced in this work which employs solutions of the continuous relaxation of the set-covering formulation of Bin Packing Problem. These high quality upper bounds are computed inexpensively and dominate the ones generated by state-of-the-art methods

Exploring the Emotional Language in the Twilight Novel as a Literary Discourse: An Appraisal Theory Analysis

Emotions have always been a mysterious realm of human beings gaining an understanding of which requires the collaboration of scholars from multiple disciplines. This study employed the Appraisal Theory (Martin & White, 2005) of evaluations and emotions to explore the manifestation of emotions in a popular modern prose fiction, the first book of the twilight series by Stephenie Meyer (2009) - Twilight. The objective of the study was to gain a deep understanding of how a bestselling literary prose fiction, Twilight, employs human emotions, and thus “affect”, to impose its “effect” on the reader. I applied the affect sub-system of the attitude system to 10000 words of the novel Twilight. I used a discourse analytic method to analyze the text along with a quantitative method to tabulate the frequencies of each type of emotion. Results showed that Twilight tends to employ a negative language in expressing attitudinal evaluations of affect and is inclined to employ an indirect way of expressing emotions. In a total of 445 instances of affect that were found in Twilight, the feeling of “insecurity” comprised the majority (39%) and after that, the feelings of “happiness” and “dissatisfaction” had an equal share of 19%. This study is a step toward understanding how to apply Appraisal Theory to literary texts to understand the evaluative language that is used in such texts. Also, it sheds light on how emotional language contributes to the features of such genre - a vampire-themed suspense romance

Location data privacy : principles to practice

A thesis submitted in partial fulfillment of the requirements for the degree of Doctor in Information Management, specialization in Geographic Information SystemsLocation data is essential to the provision of relevant and tailored information in location-based services (LBS) but has the potential to reveal sensitive information about users. Unwanted disclosure of location data is associated with various threats known as dataveillance which can lead to risks like loss of control, (continuous) monitoring, identification, and social profiling. Striking a balance between providing a service based on the user’s location while protecting their (location) privacy is thus a key challenge in this area. Although many solutions have been developed to mitigate the data privacy-related threats, the aspects involving users (i.e. User Interfaces (UI)) and the way in which location data management can affects (location) data privacy have not received much attention in the literature. This thesis develops and evaluates approaches to facilitate the design and development of privacy-aware LBS. This work has explicitly focused on three areas: location data management in LBS, the design of UI for LBS, and compliance with (location) data privacy regulation. To address location data management, this thesis proposes modifications to LBS architectures and introduces the concept of temporal and spatial ephemerality as an alternative way to manage location privacy. The modifications include adding two components to the LBS architecture: one component dedicated to the management of decisions regarding collected location data such as applying restriction on the time that the service provider stores the data; and one component for adjusting location data privacy settings for the users of LBS. This thesis then develops a set of UI controls for fine-grained management of location privacy settings based on privacy theory (Westin), privacy by design principles and general UI design principles. Finally, this thesis brings forth a set of guidelines for the design and development of privacy-aware LBS through the analysis of the General Data Protection Regulation (GDPR) and expert recommendations. Service providers, designers, and developers of LBS can benefit from the contributions of this work as the proposed architecture and UI model can help them to recognise and address privacy issues during the LBS development process. The developed guidelines, on the other hand, can be helpful when developers and designers face difficulties understanding (location) data privacy-related regulations. The guidelines include both a list of legal requirements derived from GDPR’s text and expert suggestions for developers and designers of LBS in the process of complying with data privacy regulation

Behavior of Liquid Bridges between Nonparallel Surfaces

Formation of liquid bridges between two solid surfaces is frequently observed in industry and nature, e.g. printing. When the two solid surfaces are not parallel (with dihedral angle between them), two significant phenomena emerge in the bridge behavior: First, if exceed a critical angle (_c), the bridge is no longer stable and propel itself horizontally towards the cusp of the surfaces. Second, if a stable bridge is squeezed and stretched, a horizontal bulk motion of the bridge along the surfaces can be observed. Through both experimental and numerical studies, we demonstrated that _c can be increased by increasing advancing contact angle (_a), and Contact Angle Hysteresis (CAH) of the surfaces. We also demonstrated that the magnitude of the bulk motion can be increased by increasing , the amount of compressing and stretching, and/or by decreasing _a and CAH of the surfaces

Galois 2-Extensions

The inverse Galois problem is a major question in mathematics. For a given base field and a given finite group $G$, one would like to list all Galois extensions $L/F$ such that the Galois group of $L/F$ is $G$. In this work we shall solve this problem for all fields $F$, and for group $G$ of unipotent $4 \times 4$ matrices over $\mathbb{F}_2$. We also list all $16$ $U_4 (\mathbb{F}_2)$-extensions of $\mathbb{Q}_2$. The importance of these results is that they answer the inverse Galois problem in some specific cases. This is joint work with J\\u27an Min\\u27a\v{c} and Nguyen Duy T\^an

On the Extended Hensel Construction and its Application to the Computation of Real Limit Points

The Extended Hensel Construction (EHC) is a procedure which, for an input bivariate polyno- mial with complex coefficients, can serve the same purpose as the Newton-Puiseux algorithm. We show that the EHC requires only linear algebra and univariate polynomial arithmetic. We deduce complexity estimates and report on a software implementation together with experimental results. This work is motivated and illustrated by two applications. The first one is the computation of real branches of space curves. The second one is the computation of limits of real multivariate rational function. For the latter, we present an algorithm for determining the existence of the limit of a real multivariate rational function q at a given point p which is an isolated zero of the denominator of q. When the limit exists, the algorithm computes it, without making any assumptions on the number of variables

Promoter regulation of the <em>Craterostigma plantagineum Cp LEA-like 11-24</em> gene and functional characterization of its transcription factor (CpbZIP1)

The resurrection plant Craterostigma plantagineum, a member of Linderniaceae family, is distributed in areas with variable water availability in Southern Africa. Two closely related species, L. brevidens which is endemic to montan rain forest of Africa and L. subracemosa which is found in central and Southern Africa, are used for comparative analyses for unravelling the molecular mechanisms of desiccation tolerance. While C. plantagineum and L. brevidens are desiccation tolerant, L. subracemosa represents a desiccation sensitive species. Desiccation tolerance is a very complex trait. Many genes that are involved in desiccation tolerance and the proteins that are encoded by these genes have been characterized in C. plantagineum. The Cp LEA-like 11-24 is one of these stress inducible genes in C. plantagineum that has been extensively studied both at the transcriptional and posttranscriptional level. Studies have been performed on the promoter regulation and transcription factor binding along with comparative promoter analyses between two desiccation tolerant and a desiccation sensitive species. Since promoter regions are the main regulatory elements for enhancing the transcriptional efficiency, developing an efficient transient transformation system was required to analyze promoter functions in response to different abiotic stresses. In this study, an efficient Agrobacterium-mediated transient transformation method was developed in three closely related Linderniaceae species. Different parameters that are important for enhancing the transformation efficiency were considered. These parameters include leaf size, Silwet L-77 concentration, bacterial density and duration of co-cultivation. After optimization, the activities of the minimal stress inducible promoter fragments of the LEA-like 11-24 from three species were examined under ABA and osmotic stress using optimized Agrobacterium co-cultivation method. The transformation efficiency was found to be 100% in all three species. In addition, the induction pattern of each promoter fragment under ABA and osmotic stress was comparable with that of stably transformed plants or particle bombardment, suggesting this as the most suitable method for quantitatively analyzing promoter activity in the three species. The optimized method was used for cross comparison of the LEA-like 11-24 promoter fragments among two desiccation tolerant and a sensitive species to understand the effect of trans-regulatory factors in activating the LEA-like 11-24 promoter fragments. The results demonstrated that both desiccation tolerant and sensitive species contain essential trans-regulatory factors for the activity of LEA-like 11-24 promoter fragments. Using a yeast-one-hybrid system, it was previously shown the Cp LEA-like 11-24 promoter fragment interacts with CpbZIP1 protein. The CpbZIP1 belongs to the S1-class of AtbZIP transcription factors from Arabidopsis and has been shown to have 47% protein sequence identity with AtbZIP53. Transcript expression analysis of CpbZIP1 in response to ABA, dehydration and salt stress demonstrated the stress responsiveness of this gene. S1-class members of AtbZIP from Arabidopsis have complex expression patterns in different stress responses. The CpbZIP1 from C. plantagineum also showed similar complex expression pattern in response to stress. The function of CpbZIP1 transcription is completely unknown in C. plantagineum. In a functional study of the CpbZIP1 transcription factor, transgenic Arabidopsis plants overexpressing CpbZIP1 exhibited dwarf phenotype, abnormality in flower structure and small siliques suggesting that CpbZIP1 interferes with the developmental processes. Physiological and molecular data from transgenic plants overexpressing CpbZIP1 revealed the contribution of CpbZIP1 in remobilization of carbon/nitrogen or maintaining homeostasis of energy, as obtained for the bZIP homologue in Arabidopsis (AtbZIP53). Time dependent expression of CpbZIP1 revealed that apart from the function of CpbZIP1 in abiotic stress, most likely CpbZIP1 is regulated by circadian clock rhythm. The results from this study suggests that CpbZIP1 is stress inducible and involved in multiple functions like growth, flower development, accumulation of proline, remobilizing carbon/nitrogen and maintaining homeostasis of energy in low energy conditions