Optimizing High-Load Systems with Asynchronous Programming Techniques

Developing interactive and distributive softwares is a complicated task for many reasons including the nature of this technique of programming; asynchronous programming. In this style of programming, there is no synchronization between running processes concerning message-posting communications. Therefore the presence of nonterminating executions for asynchronous programs, as a result of simple programming errors, is common.

Internet Protocol (IP) video surveillance systems have been increasingly adopted in modern applications, such as smart homes and industrial automation. These systems often handle sensitive data, such as bank activity or household routines. However, cameras are typically a vulnerable spot when it comes to cybersecurity due to unsecured network connections and poor encryption. In 2023,16% of vulnerabilities discovered in smart homes involved video surveillance devices. Conversely, comprehensive studies on this issue remain scarce in the literature. Hence, this paper proposes a methodology for discovering vulnerabilities in video surveillance cameras, applications, and data streams. Additionally, a case study is conducted on two popular camera models in Brazil. Results show that 16 vulnerabilities were discovered, including a failure in the login attempt blocking mechanism in the latest app version for one of the cameras. This previously unknown vulnerability was reported to the manufacturers.

Cloud-native performance testing has emerged as a critical discipline for ensuring application reliability and user experience in modern distributed systems. Unlike traditional testing methods designed for monolithic architectures, cloud-native approaches leverage distributed load generation, chaos engineering principles, and infrastructure-as-code frameworks to evaluate application behavior across dynamic, auto-scaling environments. By integrating comprehensive observability with performance testing, organizations can identify complex inter-service dependencies, container orchestration impacts, and resource contention issues that would otherwise remain undetected until production. The evolution from periodic testing events to continuous performance validation within CI/CD pipelines enables earlier detection of potential issues, substantially reducing customer impact and operational costs. Case studies across e-commerce, financial services, and media streaming sectors demonstrate how these advanced testing methodologies deliver significant improvements in transaction success rates, response times, and system availability while simultaneously reducing infrastructure costs.

SummaryConcurrent programming is increasingly present in modern applications. Although it provides higher performance and better use of available resources, the mechanisms of interaction between processes/threads result in a greater challenge for software testing activity. The nondeterminism present in those applications is one of the main issues during the test activity since the same test input can produce different possible execution paths, which may or not contain defects. The test data automatic generation can alleviate this problem, ensuring higher speed and reliability in software testing activity. This paper explores the automatic test data generation for concurrent programs through Genetic Algorithm, a bioinspired optimization technique, and proposes a test data generation approach for concurrent programs, called BioConcST, and a new operator for the selection of test subjects, called FuzzyST, which uses fuzzy logic. The approaches were evaluated in an experimental study towards their validation. The results showed that BioConcST is more promising than the other approaches at all analyzed levels. FuzzyST, together with Elitism and Tournament operators, provided the best results; however, it proved more suitable for concurrent programs of higher complexity.

Various blocking operations, such as input/output (IO) operations, are an essential functionality of concurrent applications. However, these operations often cause efficiency-related challenges in multithreaded applications because of the single-thread access policy. IO operations' speed and efficiency heavily rely on operating system (OS) threads and scheduling processes, which is time consuming because of the insufficient distribution of OS resources. Because of their overgeneralization, required to support various usage scenarios, robust OS kernel threads are commonly heavyweight and oversized, created in a limited number, and heavily dependent on OS schedulers. Various asynchronous programming techniques tackled issues in implementing modern concurrent applications with blocking operations with the complete reconstruction of threads and their schedulers. Based on our previous preliminary research, we further explored a model of structured concurrency in Java Virtual Machine (JVM), through the updated implementation of virtual threads and accompanying schedulers, as a novel form of lightweight user-mode threads in the JVM, decoupled from OS threads and managed within the JVM. In this paper, we present our findings about the efficiency of those schedulers utilized for virtual threads on blocking operations, compared with the implementation of OS threads' schedulers, and review possibilities of reducing memory footprints and context switching costs.

3D NAND memory, featuring vertically stacked memory cells to enhance storage density and performance, serves as a critical component in modern data storage solutions and AI applications. In this paper, we investigated the electrical impact of memory hole (MH) mis-formation defects in a multi-tier three dimensional (3D) NAND memory technology. Despite being confined to local word lines (WLs) and source lines (SLs), such defects cause a global impact to all the memory cells in the same plane by slowing down their program speed. Specifically, the bit line potential of victim cells is disturbed when quick pass write (QPW) program technique is implemented. Such disturb originates from the interaction between source line and global bit line through the aggressor memory cells. Based on the failure mechanism, several approaches were proposed to improve the screen efficiency for these defects, which could otherwise become latent system failures.

Computational Fluid Dynamics (CFD) is an important research field with a broad spectrum, requiring a close interplay between mathematical modeling, numerical methods, software development, and high performance computing. Programming CFD applications is an inherently difficult task due to many factors related to numerics and software. For modern CFD applications, use of parallel computers is a must, which makes the CFD code development even more challenging. Rapid and flexible programming of a parallel CFD application calls for re-usable serial and parallel software components plus a modular overall parallel framework that allows an easy coupling between different components. Moreover, more attention needs to be put on securing the performance of the software components. This minisymposium thus attempts to shed some light into the recent developments in respect of CFD-related numerical methods, programming techniques and software libraries.

An Experience of Using LMI Technique in Student Projects

Efficient energy utilization while ensuring occupants’ comfort remains a primary objective in smart home environments. This study presents a novel smart home management methodology that integrates Deep Neural Networks (DNNs) with an optimization algorithm to enhance energy efficiency and user comfort. Unlike traditional approaches, which often focus on individual aspects of energy management or user comfort, our method comprehensively addresses both aspects by considering key environmental factors such as air quality, temperature, and illumination. By employing specialized DNNs, our approach dynamically adjusts home conditions to align with user preferences, thereby enhancing overall comfort and satisfaction. The primary innovation of our methodology lies in the Comfort Index Calculation System, which utilizes advanced DNNs to precisely quantify user comfort based on environmental conditions. This system enables our optimization algorithm to iteratively adjust environmental settings, striking a balance between user comfort and energy consumption. By continuously learning from user feedback and environmental data, our integrated approach ensures that smart homes adapt to occupants’ evolving preferences and external conditions, thereby offering a more personalized and responsive living environment. Our results demonstrate the capability of this integrated approach in improving smart home environments, offering significant implications for environmental living and smart building automation. By bridging the gap between energy efficiency and user comfort, our study contributes to advancing the field of smart home management, ultimately realizing the full potential of energy-efficient and comfortable living environments.

Pro Spring MVC provides in-depth coverage of Spring MVC and Spring Web Flow, two highly customizable and powerful web frameworks brought to you by the developers and community of the Spring Framework. Spring MVC is a modern web application framework built upon the Spring Framework, and Spring Web Flow is a project that complements Spring MVC for building reusable web controller modules that encapsulate rich page navigation rules. Along with detailed analysis of the code and functionality, plus the first published coverage of Spring Web Flow 2.x, this book includes numerous tips and tricks to help you get the most out of Spring MVC, Spring Web Flow, and web development in general. Spring MVC and Spring Web Flow have been upgraded in the new Spring Framework 3.1 and are engineered with important considerations for design patterns and expert object-oriented programming techniques. This book explains not only the design decisions of the frameworks, but also how you can apply similar designs and techniques to your own code. This book takes great care in covering every inch of Spring MVC and Spring Web Flow to give you the complete picture. Along with all the best known features of these frameworks, youll discover some new hidden treasures. Youll also learn how to correctly and safely extend the frameworks to create customized solutions. This bookis for anyone who wishes to write robust, modern, and useful web applications with the Spring Framework. What youll learn Key Spring Framework fundamentals How to use the Spring MVC architecture How to develop with the DispatcherServlet How to write Controllers How to work with Resolving and Implementing Views What are the supported View Types How to customize your website What isand how to use the Spring Web Flow framework How to test your Spring MVC applications How to implement Spring Security Who this book is for This book is for Spring or Java EE application developers who want to learn and fully leverage Spring's Web-tier creator and framework, Spring MVC. This book is also for experienced enterprise and Java programmers who are new to the Spring Framework. Table of Contents Configuring a Spring Development Environment Spring Framework Fundamentals Web Application Architecture Spring MVC Architecture Implementing Controllers Implementing Controllers Advanced REST and AJAX Resolving and Implementing Views Testing Spring MVC Applications Spring Web Flow Building Applications with Spring Web Flow Advanced Spring Web Flow Spring Security Cloud Foundry - Deploying to the Cloud

Expert Spring MVC and Web Flow provides in-depth coverage of Spring MVC and Spring Web Flow, two highly customizable and powerful web frameworks brought to you by the developers and community of the Spring Framework. Spring MVC is a modern web application framework built upon the Spring Framework, and Spring Web Flow is a new project that compliments Spring MVC for building reusable web controller modules that encapsulate rich page navigation rules. Along with detailed analysis of the code and functionality, plus the first-published coverage of Spring Web Flow, this book includes numerous tips and tricks to help you get the most out of Spring MVC, Spring Web Flow, and web development in general. Spring MVC and Spring Web Flow are engineered with an important consideration for design patterns and expert object oriented programming techniques. This book explains not only the design decisions of the frameworks, but also how you can apply similar designs and techniques to your own code. This book takes great care in covering every inch of Spring MVC and Spring Web Flow to give you the complete picture. Along with all the best known features of these frameworks, youll discover some new hidden treasures. Youll also learn how to correctly and safely extend the frameworks to create customized solutions. From beginner to expert, this book is for anyone who wishes to write robust, modern, and useful web applications with the Spring Framework. Table of Contents Introduction Spring Fundamentals Spring MVC Application Architecture Jump into Spring MVC The Processing Pipeline The Controller Menagerie The View Layer Supported View Types Validation Testing Spring MVC Applications Introduction to Spring Web Flow Advanced Spring Web Flow

Inverter systems play a critical role in modern power conversion and energy management applications, where they often operate under diverse and complex modes. The presence of multiple operating modes leads to varying data distributions, posing significant challenges for accurate fault detection across different working scenarios. Existing methods struggle to disentangle mode-invariant and mode-specific features that effectively represent incipient faults, while also lacking selective attention across the disentangled feature spaces. To address this issue, this article proposes a shared and exclusive representation learning model (SERLM) for fault detection in multimode inverter systems. SERLM leverages shared and exclusive modules to extract mode-invariant and mode-specific features, respectively, and employs a novel multi-scale regularized channel attention (MRCA) strategy to enhance feature fusion. Additionally, two statistics are designed: one based on shared features to detect global anomalies across modes and another derived from reconstruction error to capture localized deviations. The effectiveness of feature extraction in SERLM is rigorously analyzed from a theoretical perspective. The proposed approach is validated through experiments on a power inverter system, demonstrating its superiority in detecting incipient faults under multiple modes, achieving a fault detection rate that is 6.25% higher than state-of-the-art methods.

SummaryIn this article we present an application of the Usage Control paradigm to a Smart Home infrastructure, based on a model extension and structured use of obligations. In the proposed extended model obligations are exploited to enforce two different access revocation time, namely revoke and suspend. This increases the policy expressiveness and enable to optimize the resource usage. Furthermore, obligations are exploited to send commands via IFTTT to different interconnected Smart Home devices, to impose safety‐relevant behaviors, or to act on policy attributes to implement a self‐healing paradigm for revoked sessions. The article is motivated by a parental control use case where deep learning is used in combination with Usage Control to regulate dynamically viewing rights of a smart‐TV and interactions with interconnected devices. Accuracy and performance experiments show the effectiveness and feasibility of the proposed work.

ContextualHomeLLM is a state-of-the-art Large Language Model (LLM) specifically designed to enhance user interactions and smart home management. Leveraging the power of Transformer architecture, this model is trained to understand, interpret, and respond to user queries, commands, and contextual cues within the smart home ecosystem. By integrating advanced contextual understanding, personalized recommendations, and real-time control, ContextualHomeLLM offers an innovative approach to seamless smart home control and assistance.

IoT has redefined the interaction of human life with smart objects and added a new dimension to it. Thus, we are able to connect to media and anything at any place and anywhere. The Internet of things (IoT) is often seen as a common problem area, despite options being proposed for a wide range of applications. Nonetheless, confidentiality and security requirements are very unique with reference to the requirements of a native smart home. This paper discusses the smart home protocols, which are used for short range communication with low consumption of power. We have also discussed the security issues related to smart home management. Paper also discusses about the smart lock management which we have explained in detail with its implementation protocol and other challenges. The adaption of the IoT is increasing day by day which benefits to all of us, but at the same time it also challenges us to keep addressing the issues with timely manner.