Real-time Database Management Research Articles

Wind Chat: Robust & Dynamic Flutter Messaging Application

"Wind Chat" is an Android messaging application developed using Flutter and Google Firebase. It enables users to sign in with their Gmail accounts, send friend requests, and engage in real-time messaging. It is a robust messaging application developed using cutting-edge technologies - Flutter and Google Firebase. Flutter, an open-source UI software development toolkit, allows for the creation of natively compiled applications for mobile, web, and desktop from a single codebase. Its expressive and flexible framework ensures a seamless user experience across various platforms. Complementing Flutter, Google Firebase serves as the backend infrastructure, providing a suite of powerful tools for authentication, real-time database management, and cloud storage. Firebase Authentication ensures secure user sign-ins through various methods, while Firebase Real time Database facilitates dynamic and synchronized data updates in real-time. Additionally, Firebase Cloud Storage caters to the reliable storage of multimedia content, a pivotal aspect of Wind Chat's functionality. This integration ensures secure and efficient user authentication and authorization, while also enabling dynamic and responsive data handling, critical for a real-time messaging application like Wind Chat. The combination of Flutter and Firebase empowers "Wind Chat" with a compelling and dynamic user interface, ensuring fluid navigation and an intuitive messaging experience. This fusion of innovative technologies underpins Wind Chat's ability to deliver a feature-rich and user-centric platform for seamless communication.

Performance Evaluation of Face Recognition System (FRS) Developed with Haar Cascade and MongoDB Integration in Recognition of Covered Faces

Although traditional face recognition systems (FRS) can detect with a certain success rate whether a mask is worn, they may fail due to the fact that most of the faces of the people who wear masks are covered. The difficulties arising from the fact that a significant part of the faces of individuals wearing masks are covered limits the performance of existing FRSs. In this research, it is aimed to integrate the Haar Cascade method with the MongoDB database in real time using the OpenCV library for mask-wearing face recognition and to demonstrate its performance with extensive experiments. In the experiments, the data set created within the scope of this study from realistic face images, in which most of the masked faces are covered, was used. Our research has shown that the accuracy of face recognition is 85% for masked faces, 61% for unmasked faces, and 41% when half of the face is covered by a different object. It is considered that this study will contribute to the literature in terms of providing a more effective and applicable mask detection solution by combining the Haar Cascade method with real-time database management integration.

An IoT-Based Wristband for Automatic People Tracking, Contact Tracing and Geofencing for COVID-19.

The coronavirus disease (COVID-19) pandemic has triggered a huge transformation in the use of existing technologies. Many innovations have been made in the field of contact tracing and tracking. However, studies have shown that there is no holistic system that integrates the overall process from data collection to the proper analysis of the data and actions corresponding to the results. It is critical to identify any contact with infected people and to ensure that they do not interact with others. In this research, we propose an IoT-based system that provides automatic tracking and contact tracing of people using radio frequency identification (RFID) and a global positioning system (GPS)-enabled wristband. Additionally, the proposed system defines virtual boundaries for individuals using geofencing technology to effectively monitor and keep track of infected people. Furthermore, the developed system offers robust and modular data collection, authentication through a fingerprint scanner, and real-time database management, and it communicates the health status of the individuals to appropriate authorities. The validation results prove that the proposed system identifies infected people and curbs the spread of the virus inside organizations and workplaces.

Analysis on NSAW Reminder Based on Big Data Technology

NSAWS is an intelligent and real-time large database management system. By analyzing the user identity data and access rights contained in the collected information, the NSAWS finds out the potential risks and issues an alarm notice in a timely manner. This paper mainly studies how to strengthen the prevention of network attacks in BD environment from the following aspects. This paper first introduces the common technology on the Internet in our country and its application status; secondly, it expounds the architecture, deployment mode and operation mode of the large database system based on the basic security facilities such as cloud computing platform and firewall. Then the traditional NSAWS is analyzed and the simulation platform is tested. The results show that the platform has high accuracy and stability in alerting network security hazards and can effectively protect network security.

Device Identity-Based User Authentication on Electronic Payment System for Secure E-Wallet Apps

E-wallets are a modern electronic payment system technology that easily recognize consumer interest, making our transactions very convenient and efficient. E-wallets are intended to substitute the existing physical wallet, which may tell others something about us as a person. That is why using a physical wallet is a unique, personal experience that cannot be duplicated. A solution would be to replace the physical wallet with an e-wallet on an existing mobile device. The personal nature of the e-wallet is that it should be installed on a unique device. One of the fundamental protections against any illegal access to e-wallet application is through authentication. In particular, the fundamental authentication category used in an existing e-wallet is based on knowledge (i.e., what you know), ownership (i.e., what you have), and biometric (i.e., what you are) authentication, which are sometimes prone to security threats such as account takeover, sim swapping, app cloning, or know your customer verification attacks. The design of an e-wallet authentication on mobile device solution must take into consideration the intensity of the security. To address this problem, this study proposes a design of e-wallet apps with an extension security element that focuses on the device identity in the existing user authentication mechanism. This study covers four fundamental categories of authentication: password, one time password, fingerprints, and international mobile equipment identifier. Using IMEI limits an e-wallet to be in one specific device in one time; this brings it into line with the nature of a physical wallet. In addition, it will be ready to handle the mentioned threats above, which will ultimately result in the far more reliable to use of e-wallet apps. The proposed authentication design has two phases, a registration phase and an authentication phase. The proposed method has been developed and implemented based on an Android Studio Firebase real-time database management and PayPal. In addition, the complete design has been evaluated using functional requirement testing to see how closely it meets functionality requirements. The results obtained from functional testing show that the functionalities of the proposed method meet the requirements, and one cannot use a same account on two devices; hence, it is secure from attacks. The result also shows that the proposed method has no errors. Moreover, it has been shown that our proposed method has better security parameters in terms of the existing method.

Energy, environmental, economic and social equity (4E) pressures of COVID-19 vaccination mismanagement: A global perspective

Vaccination now offers a way to resolve the COVID-19 pandemic. However, it is critical to recognise the full energy, environmental, economic and social equity (4E) impacts of the vaccination life cycle. The full 4E impacts include the design and trials, order management, material preparation, manufacturing, cold chain logistics, low-temperature storage, crowd management and end-of-life waste management. A life cycle perspective is necessary for sustainable vaccination management because a prolonged immunisation campaign for COVID-19 is likely. The impacts are geographically dispersed across sectors and regions, creating real and virtual 4E footprints that occur at different timescales. Decision-makers in industry and governments have to act, unify, resolve, and work together to implement more sustainable COVID-19 vaccination management globally and locally to minimise the 4E footprints. Potential practices include using renewable energy in production, storage, transportation and waste treatment, using better product design for packaging, using the Internet of Things (IoT) and big data analytics for better logistics, using real-time database management for better tracking of deliveries and public vaccination programmes, and using coordination platforms for more equitable vaccine access. These practices raise global challenges but suggest solutions with a 4E perspective, which could mitigate the impacts of global vaccination campaigns and prepare sustainably for future pandemics and global warming.

Improving the quality of service of real-time database systems through a semantics-based scheduling strategy

A real-time database management system (RTDBMS) aims to manage applications with a large number of data being accessed by update and user transactions having to meet some time constraints. We are interested in improving the quality of service (QoS) in RTDBMSs by optimising the execution of transactions to improve meeting their deadlines. A new scheduling strategy is developed and evaluated into a QoS management architecture called feedback control scheduling (FCS) proposed for RTDBMSs. The proposed strategy is based on the new advanced earliest deadline first based on transactions aggregation and data semantic links (AEDF-TAL-DSL) protocol we developed. It introduces new parameters relating to the aggregation links (defined according to the type of operations composing the transactions and the data they access) existing between transactions as well as the semantic links appearing between the users' queries. We also show the contributions provided by our approach through simulation results.

Research on Real-Time Database Recovery Method of Smart Grid System Based on IEC61970 Standard

Real-time database management system plays an important role in power grid system. With the increasing development of smart grid, the problem of data integrity security in real-time database has attracted more and more attention. Research on real-time database recovery Method of Smart Grid system is based on IEC61970 standard using RFID algorithm. After the data integrity is destroyed, it takes only a rollback malicious transaction, without having to roll back all transactions, the transaction conflict caused by the transaction revocation can be avoided, that can improve the survivability of real-time databases, protect the integrity of the real-time database of smart grids, and improve power grid dispatching system. Therefore, real-time database recovery Method plays an important role in power grid dispatching system.

QoS Aware Replica Control Strategies for Distributed Real Time Database Management System

In distributed real time database management system (DRT-DBMS), QoS aware replication control strategy is necessary to ensure availability and to improve the system performance. Since user request and need of data is dynamic in nature, it requires an approach which addresses the problem of data distribution and also resolves them in DRT-DBMS. A large quantity of data file is produced so we need a dynamic replication approach through which we can reduce the data access time. In order to replicate it, at the nearest site, replica placement and replacement algorithms are required to be evaluated. This paper presents a heuristic approach Greedy-Cover Firefly algorithm in which replica is placed dynamically based on QoS requirement and replaced with the optimal adaptive replica replacement algorithm for each data object. The replication cost required for copying data object to each set of a node is calculated to select the optimal node. Here, the replication decision is taken on the basis of access history of data on multiple sites. Due to the limited storage capacity of each node, the value of each file is calculated, and the file with the smallest value is removed to replace other files. A detailed simulation shows that the proposed algorithms can greatly improve the system performance to reduce the system resources consumed with respect to time and QoS requirement.

Model Driven Engineering for Quality of Service Management

Real-time applications managing a large number of real-time data require the use of Real-time Database Management Systems (RTDBMS) to meet temporal constraints of both real-time data and transactions. However, a RTDBMS has a dynamic workload and may be frequently overloaded since the arrival times and workloads of user transactions are unpredictable. Therefore, Quality of Service management solutions have been proposed to guarantee the stability of RTDBMS even during unpredictable overload periods. While effective, the design and reuse of these solutions is challenging because they are not formally modeled and there is no tool neither a methodology that helps us design such solutions. To address these issues, the authors propose a design framework based on the Model-Driven Engineering approach providing a modeling architecture, a strategic methodology and a software tool to support modeling and reusing such solutions. The framework is implemented and tested for a real Qos management solution.

Simulation framework for real-time database on WSNs

Wireless sensor networks (WSNs) have been the focus of many research works. Nowadays, because of the time-critical tasks of several WSN applications, one of the new challenges faced by WSNs is handling real-time storage and querying the data they process. This is the real-time database management on WSN and it deals with time-constrained data, time-constrained transactions, and limited resources of wireless sensors. Developing, testing, and debugging this kind of complex system are time-consuming and hard work. The deployment is also generally very costly in both time and money. Therefore in this context, the use of a simulator for a validation phase before implementation and deploying is proved to be very useful. The aim of this paper is to describe the different specificities of real-time databases on WSN and to present a model for a simulation framework of the real-time databases management on WSN that uses a distributed approach. Then, the model of the simulator is described and developed in Java and a case study with some results demonstrates the validity of the structural model.

Dynamic Real Time Distributed Sensor Network Based Database Management System Using XML, JAVA and PHP Technologies

Wireless Sensor Network (WSN) is well known for distributed real time systems for various applications. In order to handle the increasing functionality and complexity of high resolution spatio-temporal sensory database, there is a strong need for a system/tool to analyse real time data associated with distributed sensor network systems. There are a few package/systems available to maintain the near real time database system/management, which are expensive and requires expertise. Hence, there is a need for a cost effective and easy to use dynamic real-time data repository system to provide real time data (raw as well as usable units) in a structured format. In the present study, a distributed sensor network system, with Agrisens (AS) and FieldServer (FS) as well as FS-based Flux Tower and FieldTwitter, is used, which consists of network of sensors and field images to observe/collect the real time weather, crop and environmental parameters for precision agriculture. The real time FieldServer-based spatio-temporal high resolution dynamic sensory data was converted into Dynamic Real-Time Database Management System (DRTDBMS) in a structured format for both raw and converted (with usable units) data. A web interface has been developed to access the DRTDBMS and exclusive domain has been created with the help of open/free Information and Communication Technology (ICT) tools in Extendable Markup Language (XML) using (Hypertext preprocessor) PHP algorithms and with eXtensible Hyper Text Markup Language (XHTML) self-scripting. The proposed DRTDBMS prototype, called GeoSense DRTDBMS, which is a part of the ongoing IndoJapan initiative ‘ICT and Sensor Network based Decision Support Systems in Agriculture and Environment Assessment’, will be integrated with GeoSense cloud server to provide database (dynamic real-time weather/soil/crop and environmental parameters) and modeling services (crop water requirement and simulated rice yield modeling). GeoSense-cloud server has been developed with Opera-Unite for file sharing, web server (with cost effective web server tools Windows Apache MySQL PHP-WAMP and X -any operating systems Apache MySQL PHP and Perl –XAMPP), file upload, and web proxy functionalities. Currently, the GeoSense DRTDBMS is useful to the rural farming community for ubiquitous decision making in precision agriculture aspects. In future, this DRTDBMS system could be used in climate/environmental systems to understand the micro-climatic variations in real-time mode.

Data management for component-based embedded real-time systems: The database proxy approach

We introduce the concept of database proxies intended to mitigate the gap between two disjoint productivity-enhancing techniques: component based software engineering (CBSE) and real-time database management systems (RTDBMS). The two techniques promote opposing design goals and their coexistence is neither obvious nor intuitive. CBSE promotes encapsulation and decoupling of component internals from the component environment, whilst an RTDBMS provide mechanisms for efficient and predictable global data sharing. A component with direct access to an RTDBMS is dependent on that specific RTDBMS and may not be useable in an alternative environment. For components to remain encapsulated and reusable, database proxies decouple components from an underlying database residing in the component framework, while providing temporally predictable access to data maintained in a database. Our approach provide access to features such as extensive data modeling tools, predictable access to hard real-time data, dynamic access to soft real-time data using standardized queries and controlled data sharing; thus allowing developers to employ the full potential of both CBSE and an RTDBMS. Our approach primarily targets embedded systems with a subset of functionality with real-time requirements. The implementation results show that the benefits of using proxies do not come at the expense of significant run-time overheads or less accurate timing predictions.

Broadcasting Data Items with Time Constraints Based on On-Demand Multichannel in Ubiquitous Environments

This study proposes mobile services with time constraints in ubiquitous computing environments based on on-demand multichannel broadcasting. For real-time mobile service, the need of mobile service for a real-time database management model is strong and providing real-time response to mobile transaction has became basic strategies in mobile data management. However, the resource constraints of ubiquitous computing systems make it difficult to satisfy timing requirements of supported strategies. This study provides on-line scheduling strategies for mobile data with timing constraint on multichannel broadcasting environments based on on-demand mode. The goal of this study ensures the most requests meeting their deadlines, which differs from previously proposed scheduling algorithms that aim to minimize the mean access time. The study presents a study of the performance of traditional real-time strategies and demonstrates traditional real-time algorithms which do not always perform the best in a mobile environment. The experimental results show the proposed algorithm, called on-demand broadcast program with time constraint (BPTC), outperforms miss rate for data timely delivery to mobile clients.

An improved 2PL-HP based concurrency control algorithm in real time database

In the real time database management systems the mechanism of concurrency control 2PL-high priority, by applying a sacrificing approach of the low-priority transaction during the competition with high priority transaction, not only waste the resources of the system but also decrease the system efficiency due to the increase of the transaction failure because of miss deadline. The survey is focusing on the weak points of this mechanism and presenting a new approach that by omitting the unnecessary restarts greatly improve the efficiency of the system. We also present a new approach for determining the transaction's priority to provide the possibility of more successful transaction. This approach will be more prominent especially when there is more competition among the transactions for locking the resources of the system. By modeling the behavior system in Markov model, this increase in efficiency of the system comparing to the 2PL-HP mechanism has been improved. Key words: Real time databases, concurrency control, transaction priority, performance evaluation.

Modeling selected real-time database concurrency control protocols in Uppaal

Real-time database management systems (RTDBMS) are recently subject of an intensive research. Model checking algorithms and verification tools are of great concern as well. In this paper, we show some possibilities of using a verification tool Uppaal on some variants of pessimistic and optimistic concurrency control protocols used in real-time database management systems. We present some possible models of such protocols expressed as nets of timed automata, which are a modeling language of Uppaal.

Providing Data Items with Time Constraints in Multi-Channel Broadcasting Environments

In a mobile computing system, users carrying portable devices can access database services from any location without requiring a fixed position in the networking environment. Some examples of strategies supported by databases in mobile computing include location dependent queries, long-lived transactions that require migration of data into the portable devices, form-based transactions, and online information report. Within a mobile computing environment, the need for a realtime database management model is strong, because one of the basic requirements in mobile data management is to provide real-time response to transactions of the underlying strategies. However, the resource constraints of mobile computing systems make it difficult to satisfy timing requirements of supported strategies. Low bandwidth, unreliable wireless links, and frequent disconnections increase the overhead of communication between mobile hosts and fixed hosts of the system. There are many situations in which we need to incorporate real-time constraints in broadcasting systems for mobile environments. In this paper, we study broadcast scheduling strategies for pushbased broadcast with timing constraints in the form of deadlines. Unlike previously proposed scheduling algorithms for broadcast systems which aim to minimize the mean access time, our goal is to identify scheduling algorithms for broadcast systems that ensure requests meet their deadlines. We present a study of the performance of traditional real-time strategies and mobile broadcasting strategies, and demonstrate that traditional realtime algorithms do not always perform the best in a mobile environment. We propose a multichannel model based on pushbased real-time broadcast system and also provide an efficient scheduling algorithm, called dynamic adjustment with time constraint (DATC), which is designed for timely delivery of data to mobile clients.

Evolving a model of transaction management with embedded concurrency control for mobile database systems

Transactions within a mobile database management system face many restrictions. These cannot afford unlimited delays or participate in multiple retry attempts for execution. The proposed embedded concurrency control (ECC) techniques provide support on three counts, namely—to enhance concurrency, to overcome problems due to heterogeneity, and to allocate priority to transactions that originate from mobile hosts. These proposed ECC techniques can be used to enhance the server capabilities within a mobile database management system. Adoption of the techniques can be beneficial in general, and for other special cases of transaction management in distributed real-time database management systems. The proposed model can be applied to other similar problems related to synchronization, such as the generation of a backup copy of an operational database system.

A new measure of temporal consistency for derived objects in real-time database systems

A real-time database system (RTDBS) must satisfy the timing constraints of its transactions as well as the temporal consistency constraints of its temporal data. The data is considered to be temporally consistent if it is absolutely and relatively consistent. A data object is absolutely consistent if its age is younger than an absolute threshold, and a set of data objects is considered to be relatively consistent if the dispersion of ages is smaller than a relative threshold. It is often difficult to select appropriate values for the thresholds that satisfy both absolute and relative consistency, especially in the case of objects whose values are derived (derived objects). In this paper we propose a new measure of temporal consistency for derived objects that is based on a new definition for the age of the derived object. Our proposed age provides additional insight into the temporal consistency of derived data objects and is useful for real-time database design and management.

Software architecture for a firm real-time database system

Abstract An actual development of a real-time database management system (RT-DBMS) must confront many new and practical problems which have been often ignored in previous work based on simulation. In addition to transaction scheduling, an RT-DBMS must deal with resource and data contention and enforce timing constraints. This paper discusses how current real-time technology has been applied to architect an RT-DBMS on a real-time microkernel operating system and how the problems have been addressed. We present the current software architecture of our StarBase RT-DBMS and address how it can be extended to support both guaranteed and non-guaranteed transaction processing.