A security operation center (SOC) is a cybersecurity clearinghouse responsible for monitoring, collecting and analyzing security events from organizations’ IT infrastructure and security controls. Despite their popularity, SOCs are facing increasing challenges and pressure due to the growing volume, velocity and variety of the IT infrastructure and security data observed on a daily basis. Due to the mixed performance of current technological solutions, e.g. intrusion detection system (IDS) and security information and event management (SIEM), there is an over-reliance on manual analysis of the events by human security analysts. This creates huge backlogs and slows down considerably the resolution of critical security events. Obvious solutions include increasing the accuracy and efficiency of crucial aspects of the SOC automation workflow, such as the event classification and prioritization. In the current thesis, we present a new approach for SOC event classification and prioritization by identifying a set of new machine learning features using graph visualization and graph metrics. Using a real-world SOC dataset and by applying different machine learning classification techniques, we demonstrate empirically the benefit of using the graph-based features in terms of improved classification accuracy. Three different classification techniques are explored, namely, logistic regression, XGBoost and deep neural network (DNN). The experimental evaluation shows for the DNN, the best performing classifier, area under curve (AUC) values of 91% for the baseline feature set and 99% for the augmented feature set that includes the graph-based features, which is a net improvement of 8% in classification performance. / Graduate

A grid graph is a finite embedded subgraph of the infinite integer grid. A solid grid graph is a grid graph without holes, i.e., each bounded face of the graph is a unit square. The reconfiguration problem for Hamiltonian cycle or path in a sold grid graph G asks the following question: given two Hamiltonian cycles (or paths) of G, can we transform one cycle (or path) to the other using some "operation" such that we get a Hamiltonian cycle (or path) of G in the intermediate steps (i.e., after each application of the operation)? In this thesis, we investigate reconfiguration problems for Hamiltonian cycles and paths in the context of two types of solid graphs: rectangular grid graphs, which have a rectangular outer boundary, and L- shaped grid graphs, which have a single reflex corner on the outer boundary, under three operations we define, flip, transpose and switch, that are local in the grid. Reconfiguration of Hamiltonian cycles and paths in embedded grid graphs has potential applications in path planning, robot navigation, minimizing turn costs in milling problems, minimizing angle costs in TSP, additive manufacturing and 3D printing, and in polymer science. In this thesis, we introduce a complexity measure called bend complexity for Hamiltonian paths and cycles in grid graphs, and using those measures we measure complexity of a grid graph G and give upper and lower bounds on the maximum bend complexity of an mxn grid graph. We define three local operations, flip, transpose and switch, where local means that the operations are applied on vertices that are close in the grid graph but may not be close on the path or cycle. We show that any Hamiltonian cycle or path can be reconfigured to any other Hamiltonian cycle or path in an mxn rectangular grid graph, where m <= 4, using O(|G|) flips and transposes, regardless of the bend complexities of the two cycles. We give algorithms to reconfigure 1-complex Hamiltonian cycles in a rectangular or L-shaped grid graph G using O(|G|) flips and transposes, where the intermediate steps are also 1-complex Hamiltonian cycles. Finally, we establish the structure of 1-complex Hamiltonian paths between diagonally opposite corners s and t of a rectangular grid graph, and then provide a strategy, based on work in progress, for designing an algorithm to reconfigure between any two 1-complex s, t Hamiltonian paths using switch operations. / Graduate

The decline in the profitability of credit unions with less than $10 million in assets harms the number of small credit unions available to serve local communities. Grounded in the financial intermediation theory, the purpose of this quantitative correlational study was to examine the relationship between regulatory compliance costs, operation costs, and profitability. The population of this study consisted of federally insured credit unions with less than $10 million in assets and located in the state of Texas. Archival data from the National Credit Union Administration database were collected and analyzed. Multiple regression was used to identify a statistically significant predictive model, F (2, 49) = 3.834, p = .028, R2 =.135. The implications for positive social change include the potential for credit union managers to improve decision-making processes related to current and future operations and investments, which could increase profitability and contribute to the financial prosperity of employees, employees' families, communities, and local economies.

Bakgrund: Operationer sker ibland när patienter är vakna och då med regional -eller lokalbedövning. Under denna typ av operation har operationssjuksköterskans omvårdnad en betydande roll för patientens upplevelse av situationen. Syfte: Syftet med denna studie är därför att i en systematisk litteraturstudie beskriva patientens upplevelser av att vara vaken under en operation. Metod: En systematisk litteraturstudie har utarbetats genom en systematisk sökning efter artiklar i databaserna CINAHL, PubMed och PsycInfo. Artiklar har relevansgranskats, kvalitetsgranskats och därefter har 10 artiklar inkluderats i litteraturstudien. Därefter har en tematisk analys gjorts för att bearbeta och sammanställa artiklarnas resultat för att svara på studien syfte. Resultat: Av den tematiska analysen framkom fyra teman; Smärt -och bedövningsupplevelser varierar i styrka men kan åtgärdas, operationssjuksköterskans bemötande har betydelse för välbefinnandet, fysiska och psykiska påfrestningar under operationen och operationsmiljön kan vara obehaglig och skrämmande. Slutsats: Det finns en variation hos patienterna vad gäller upplevelser av smärtan och operationsmiljön. Patienternas upplevelser av sjuksköterskornas omvårdnad under operationen ger dem en trygghet och lugn genom att operationssjuksköterskans kommunikation och information samt att hen ser till patientens värdighet, integritet och autonomi. / Background: Operations sometimes occur when patients are awake and then with regional or local anesthesia. During this type of surgery, the nurse's care plays a significant role in the patient's experience of the situation. Purpose: The purpose of this study is to describe in a systematic literature study the patient's experiences of being awake during an operation. Method: A systematic literature study has been prepared by a systematic search for articles in the databases CINAHL, PubMed and PsycInfo. Articles have been reviewed for relevance, quality checked and then 10 articles have been included in the literature study. Subsequently, a thematic analysis was done to process and compile the results of the articles in order to answer the study's purpose. Results: From the thematic analysis, four themes emerged; Pain and stunning experiences vary in strength but can be addressed, the operation nurse's treatment staff's response has significance for the well-being, physical and psychological stress during the operation and the operating environment can be unpleasant and frightening. Conclusion: There is a variation in patients in terms of experiences of the pain and the operating environment. The patients 'experiences of the nurses' care during the operation give them a sense of security and tranquility through the nurse's communication and information as well as the patient's dignity, integrity and autonomy.

Data is distributed across interconnected relations in relational databases. Relationships between tuples can be rearranged in distinct relations by matching the values of the join attribute, a process called equi-join operation. Unlike standard attempts to design efficient join algorithms in this thesis, an approach is proposed to align tuples in relation so that joins can be readily and effectively done. We position tuples in their respective relationships, called relations alignment, which has matching join attribute values in the corresponding positions. We also address how to align relations and perform joins on aligned relations. The experiments were conducted in this research to measure and analyze the efficiency of the proposed approach compared to standard MySQL joins.

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This thesis presents techniques to implement analog-to-digital converters (ADCs) under an ultra-low-supply-voltage of 0.2 V to reduce the power consumption. The thesis proposes a dynamic bulk biasing circuit to adjust the PMOS bulk voltage to balance the NMOS and PMOS drain currents to guarantee functionality in the presence of process, voltage, and temperature variations. The dynamic bulk bias circuit is analyzed rigorously to show its functionality. This thesis also describes a new comparator suitable for a 0.2-V supply using ac-coupling, stacked input pairs, and voltage-boosted load capacitor. A 10-bit 5-kS/s successive-approximation-register (SAR) ADC in a 180-nm CMOS process with a supply voltage of 0.2 V demonstrates these ideas. The ADC exhibits a differential nonlinearity (DNL) and integral nonlinearity (INL) within +0.42/-0.45 and +0.62/-0.67 LSB, respectively. The measured SFDR and SNDR at 5 kS/s with a Nyquist-frequency input are 65.9 dB and 52.1 dB, respectively. The entire ADC and dynamic bulk biasing circuitry consume 22 nW including leakage power to yield a figure-of-meirt (FoM) of 8.8 fJ/conv.-step. Measurements of multiple chips show the proposed dynamic bulk biasing fully recovers the ADC performance when the supply voltage is varied. The nW power consumption makes the design well suited for wireless sensor node and energy harvester applications.

Purpose The purpose is to identify responsibility of owners and operators for maintenance of assets, fixtures and fittings, to identify maintenance management strategies adopted for the efficient operation of hotels and to find out difficulties faced by operators in implementing these strategies. Methodology Four interviews provided supplementary data for the main data collection phase involving administration of 64 questionnaires to hotel operators and maintenance managers. Findings The hotel owner and operator have individual and joint responsibility for asset maintenance. Outsourcing is a maintenance strategy used to minimise operating costs, an important factor that guides this decision is time constraint required to deliver work. In house maintenance it is also influenced by the strategic value of the service and the availability of the resource in the market. In maintenance practice an important challenge is maintaining energy efficiency because of the increasing electronic equipment and high volume of lights.

The HVAC&R industry is looking to transition from copper-aluminum heat exchangers to all-aluminum microchannel technology. The want for the transition stemmed from seeing the performance improvement of all-aluminum microchannel radiators in the automotive industry. Applications differ between the two industries; therefore, applying this technology for HVAC&R use must be validated. Research towards operating modes of an all-aluminum heat exchanger in a defined corrosive environment will provide the industry with a better understanding of heat exchanger design and heat exchanger material selection. The worth in this is preventing overdesign and producing more efficient heat exchangers. Furthermore, ASHRAE members and the corrosion community will find value in a defined corrosion system and corrosion test procedure. The information gained through past research has progressed assessment of material performance; however, the methods improperly simulate and expedite natural weathering. The most common method being used is the ASTM (American Society of Testing Materials) Sea Water Acetic Acid Test. The research discussed in this paper was focused on improving a standard corrosion system by implementing system modifications to simulate heat exchanger operation while performing a modified wet-dry cyclic test (e.g. ASTM G85 Annex 5). The goal is to produce results that are more representative of natural corrosion behavior and its forms. Current results were gathered from five of ten samples that underwent initial testing. Finally, possible improvements towards the chamber system and the test method, including the salt solution, are discussed.