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关键词： Propagation   Cellular telephones   Cameras   Cloning   Design   Art   Engineering   Software upgrading   Third party   Integrated software   Editing   Computer science   Physics  

摘要： Context: Software systems often need to exist in many variants in order to satisfy varying customer requirements and operate under varying software and hardware environments. These variant-rich systems are most commonly realized using cloning, a convenient approach to create new variants by reusing existing ones. Cloning is readily available, however, the non-systematic reuse leads to difficult maintenance. An alternative strategy is adopting platform-oriented development approaches, such as Software Product-Line Engineering (SPLE). SPLE offers systematic reuse, and provides centralized control, and thus, easier maintenance. However, adopting SPLE is a risky and expensive endeavor, often relying on significant developer intervention. Researchers have attempted to devise strategies to synchronize variants (change propagation) and migrate from clone&own to an SPL, however, they are limited in accuracy and applicability. Additionally, the process models for SPLE in literature, as we will discuss, are obsolete, and only partially reflect how adoption is approached in industry. Despite many agile practices prescribing feature-oriented software development, features are still rarely documented and incorporated during actual development, making SPL-migration risky and error-prone. Objective: The overarching goal of this PhD is to bridge the gap between clone&own and software product-line engineering in a risk-free, smooth, and accurate manner. Consequently, in the first part of the PhD, we focus on the conceptualization, formalization, and implementation of a framework for migrating from a lean architecture to a platform-based one. Method: Our objectives are met by means of (i) understanding the literature relevant to variant-management and product-line migration and determining the research gaps (ii) surveying the dominant process models for SPLE and comparing them against the contemporary industrial practices, (iii) devising a framework for incremental SPL adoption, and

关键词： Cloud computing   Encryption   Social networking (online)   Protocols   Keyword search   Servers   Computer science   Social graph search   versatile queries   searchable encryption   secure computation  

摘要： With the widespread adoption of cloud computing, it is increasingly popular for online social network (OSN) service providers to leverage the public cloud as a back-end to manage their services for the cloud's well-understood benefits. However, the cloud is also notoriously subject to a wide attack surface, making it an imperative need to embed security in the cloud-backed OSN service from the very beginning. In light of this, in this paper, we design, implement, and evaluate PeGraph, the first system simultaneously allowing private, efficient, and rich queries over encrypted social graphs. PeGraph is aimed at safeguarding the confidentiality of the social graph at the cloud, while preserving the functionality of social search, a key enabler for quality OSN services like friend discovery and user targeting. PeGraph is built from a delicate synergy of insights from social graph modelling and lightweight cryptography such as searchable encryption and additive secret sharing, supporting rich social search queries like exact queries, fuzzy queries, and mixed queries. PeGraph also allows the cloud to obliviously render the encrypted social search results in a ranked order according to their importance, as per users' preferences. Extensive experiments demonstrate that PeGraph can securely process a wide range of practical social search queries within 1 second, over a real-world social graph consisting of millions of entities.

关键词： Performance evaluation   Computer science   Internet of Things   Software engineering  

关键词： Computer science  

ISBN: (数字)9781119820963;9781119820949 ISBN: (纸本)9781119820864

摘要： A hands-on roadmap to using Python for artificial intelligence programming In Practical Artificial Intelligence Programming with Python: From Zero to Hero, veteran educator and photophysicist Dr. Perry Xiao delivers a thorough introduction to one of the most exciting areas of computer science in modern history. The book demystifies artificial intelligence and teaches readers its fundamentals from scratch in simple and plain language and with illustrative code examples. Divided into three parts, the author explains artificial intelligence generally, machine learning, and deep learning. It tackles a wide variety of useful topics, from classification and regression in machine learning to generative adversarial networks. He also includes:

• Fulsome introductions to MATLAB, Python, AI, machine learning, and deep learning
• Expansive discussions on supervised and unsupervised machine learning, as well as semi-supervised learning
• Practical AI and Python “cheat sheet” quick references

This hands-on AI programming guide is perfect for anyone with a basic knowledge of programming—including familiarity with variables, arrays, loops, if-else statements, and file input and output—who seeks to understand foundational concepts in AI and AI development.

ISBN: (数字)9780262371841

摘要： Coding for a purpose: helping young people combine journalism, data, design, and code to make media that makes a *** are urged to teach “code for all”—to make a specialized field accessible for students usually excluded from it. In this book, Clifford Lee and Elisabeth Soep instead ask the question, “Code for what?” What if coding were a justice-driven medium for storytelling rather than a narrow technical skill? What if “democratizing” computer science went beyond the usual one-off workshop and empowered youth to create digital products for social impact? Lee and Soep answer these questions with stories of a diverse group of young people in Oakland, California, who combine journalism, data, design, and code to create media that makes a *** teenage and young adult producers created interactive projects that explored gendered and racialized dress code policies in schools; designed tools for LBGTQ+ youth experiencing discrimination; investigated facial recognition software and what can be done about it; and developed a mobile app to promote mental health through self-awareness and outreach for support, and more, for distribution to audiences that could reach into the millions. Working with educators and media professionals at YR Media, an award-winning organization that helps young people from underserved communities build skills in media, journalism, and the arts, these teens found their own vibrant answers to “why code?” They code for insight, connection and community, accountability, creative expression, joy, and hope.

关键词： Computer science   Artificial intelligence  

摘要： The goal of this dissertation is to demonstrate the computational advantages gained by exploiting the graphical structures implicit in data, as well as the graph-theoretical underpinnings of computational architectures such as neural networks. A new computational architecture, Ortus, that uses a graph-based model to process structured data is introduced, which can be thought of as an approximation to a biologically-grounded Boltzmann machine. Next, sparse super-regular networks are developed to show the applicability of using sparse architectural network design toward solving real-world problems. Then, probabilistic hybrid graph convolutional networks show the practical applications of leveraging the inherent structural interdependencies within data by using hybrid neural network architectures. Within these networks, subnetworks are geared to extract particular types of relationships, similar to how Ortus routes specific types of information through predetermined channels. Finally, the benefits of merging structural sparsity with structured information processing are demonstrated by substituting super-regular network layers in place of fully-connected layers within the probabilistic hybrid architectures.

关键词： Barriers   Black police officers   Diversity   Occupational   police culture  

摘要： The success of an organization is directly dependent upon its the culture. Research was scarce regarding historical police culture and its impacts on Black law enforcement officers. The purpose of the study was to explore how occupational barriers of historical police culture have impacted Black law enforcement officers who policed at least 20 years in Florida. A phenomenological qualitative approach guided the collection and analysis of data from semi-structured interviews with 30 purposefully selected retired law enforcement officers in Central and South Florida. Ten themes: (a) police culture, (b) industry expectations (c) occupational barriers, (d) systematic inequality, (e) same race competition, (f) racial disparity, (g) diversity, inclusion, and equity efforts (h) internal conflict, (i) affects, and (j) coping mechanisms emerged from bracketing followed by manual coding. The experiences and perspectives of the 30 participants provided new knowledge, ideas, and insight that may prove helpful to other law enforcement and their perspectives on police culture. Findings indicate that shattering occupational barriers is critical to police culture. Most participants recognized that occupational barriers from police culture highly impacts career experiences, goals, and personal drive. The officers expressed a desire to see change and improvement in police culture through diversity, equity, and inclusion practices. The study results were consistent with earlier research which indicated that a diverse, equitable, and inclusive culture is positive for employees and organizations (Parikh, 2021). As law enforcement agencies reform and progress, they should introduce streamline policies that ensure diversity, equity, and inclusion (DEI) are included in job assignments, discipline, and promotional processes. As culture evolves, formal programs should also incorporate discussions to address any questions or concerns about DEI.

关键词： Geology   Mineralogy   Analytical chemistry   Chemistry   Computer science   Continental Dynamics   Petrology   Sedimentary Geology  

摘要： Exploration under glacial sediment cover is a necessary part of modern mineral exploration in Canada. Traditional indicator methods use visual examination to identify mineral grains in the 250 to 2000 µm fraction of till heavy-mineral concentrates (HMC). This study tests automated mineralogical methods using scanning electron microscopy to identify indicator minerals in the fine (<250 µm) HMC fraction of till. Automated mineralogy of polished grains from the fine HMC enables rapid data collection (10,000–300,000 grains/sample). Samples collected near three deposits were used to test this method: 4 from the upper amphibolite Izok Lake volcanogenic massive sulfide deposit, Nunavut, 5 from the Sisson granite-hosted W-Mo deposit, New Brunswick, and 4 from the Triple B kimberlite, Ontario. The less than 250 µm HMC fraction of till samples collected down-ice of each deposit contain ore and alteration minerals typical of their deposit type. Sulfide minerals occur mainly as inclusions in oxidation-resistant minerals, including minerals previously identified in the metamorphic alteration halo of each deposit, and are found to occur farther down-ice than the grains identified visually in the greater than 250 µm HMC fraction. Minerals that are traditionally difficult to identify using visual identification are easily discriminated by composition. The classic suite of kimberlite indicator suite is fully identified, and energy dispersive X-ray spectroscopy enables discrimination of compositional sub-populations without the use of more expensive/time consuming targeted chemical analysis techniques. This project developed a workflow for analyzing <250 µm HMC with automated mineralogy that is reproducible and relatable both within and between studies. The method described expands the detectable footprint for certain indicator minerals, identifies new indicator minerals, and enhances the information on the mineralogical composition of till samples that can be collected from till sam

关键词： Computer science   Artificial intelligence  

关键词： Network intrusion detection   Monitoring   Deep learning   Convolutional neural networks   Computer science   Systematics   Switches   Flow information export   network traffic sampling   intrusion detection   machine learning   deep learning   CNN  

摘要： Machine Learning (ML) based Network Intrusion Systems (NIDSs) operate on flow features which are obtained from flow exporting protocols (i.e., NetFlow). Recent success of ML and Deep Learning (DL) based NIDS solutions assume such flow information (e.g., avg. packet size) is obtained from all packets of the flow. However, often in practice flow exporter is deployed on commodity devices where packet sampling is inevitable. As a result, applicability of such ML based NIDS solutions in the presence of sampling (i.e., when flow information is obtained from sampled set of packets instead of full traffic) is an open question. In this study, we explore the impact of packet sampling on the performance and efficiency of ML-based NIDSs. Unlike previous work, our proposed evaluation procedure is immune to different settings of flow export stage. Hence, it can provide a robust evaluation of NIDS even in the presence of sampling. Through sampling experiments we established that malicious flows with shorter size (i.e., number of packets) are likely to go unnoticed even with mild sampling rates such as 1/10 and 1/100. Next, using the proposed evaluation procedure we investigated the impact of various sampling techniques on NIDS detection rate and false alarm rate. Detection rate and false alarm rate is computed for three sampling rates (i.e., 1/10, 1/100, 1/1000), for four different sampling techniques and for three (two tree-based, one deep learning based) classifiers. Experimental results show that systematic linear sampler - SketFlow performs better compared to non-linear samplers such as Sketch Guided and Fast Filtered sampling. We also found that random forest classifier with SketchFlow sampling was a better combination. The combination showed higher detection rate and lower false alarm rate across multiple sampling rates compared to other sampler-classifier combinations. Our results are consistent in multiple sampling rates, exceptional case is observed for Sketch Guided Samp