Mobile Code Research Articles

Reengineering Web applications into pervasive information systems

In today’s mobile-driven world, organizations face the challenge of adapting legacy Web applications to pervasive information systems, such as mobile applications, ensuring seamless accessibility across devices. This paper presents a systematic, three-phase approach to reengineering Web applications into mobile applications: Reverse-engineering, Transformation, and Forward-engineering. In the reverse-engineering phase, high-level conceptual models of the Web application are generated to capture its architecture and functionality. During the transformation phase, these models are refined using Unified Modeling Language (UML) profiles to align with the requirements of mobile systems. The forward-engineering phase utilizes the Acceleo technology, along with predefined mapping rules and code patterns, to automate the generation of mobile application code. A case study is conducted to demonstrate the effectiveness of this framework, revealing a significant reduction in manual effort throughout the reengineering process. This approach offers a scalable and efficient solution for transforming Web applications into mobile applications, contributing to advancements in model-driven engineering and software reengineering.

Client-Server Code Mobility at Runtime

Application logic is inherently distributed between client and server due to the fundamental Client/Server architecture of the Web. The individual distribution is specified at design time and remains unchanged stable, preventing individual load distribution between clients and server at runtime. Dynamic code mobility at runtime, in contrast, allows to balance the needs of users, through increased responsiveness, and software providers, through better resource usage and cost reductions. Enabled by WebAssembly, the Web ecosystem recently provides the technological foundation for relocating code units during runtime. However, leveraging these capabilities to enhance web applications with dynamic code migration presents challenges for web engineers. In response, we propose an innovative distributed Client/Server software architecture for web applications. This architecture facilitates the dynamic migration of code at runtime, and addresses the technical challenges like dependency management, control and data flow distribution, communication, and interfaces. This novel software architecture serves as a reference for web engineers aiming to enrich their web applications with dynamic code mobility. Additionally, it contributes to the ongoing reevaluation of the Web ecosystem in light of the widespread adoption and standardization of WebAssembly across major browsers. Through experimentation in four scenarios, we demonstrate the feasibility of implementing this architecture, its negligible impact on performance and the optimization potential for individual code distributions across client and server.

A generic type system for higher-order Ψ-calculi

The Higher-Order Ψ-calculus framework (HOΨ) by Parrow et al. is a generalisation of many first- and higher-order extensions of the π-calculus. In this paper we present a generic type system for HOΨ-calculi. It satisfies a subject reduction property and can be instantiated to yield both existing and new type systems for calculi, that can be expressed as HOΨ-calculi. In this paper, we consider the type system for termination in HOπ by Demangeon et al. Moreover, we derive a new type system for the ρ-calculus of Meredith and Radestock and present a type system for non-interference for mobile code.

Short message encryption technology of Beidou communication based on SM9

AbstractTo reduce the security authentication time cost, forwarding delay, and enhance message security of Beidou communication short messages, this paper proposes a Beidou communication short message encryption technology based on SM9 (Mobile Code Secure Communication). This technology uses split hierarchical clustering algorithm to cluster the short message data of Beidou Communication, in order to unify the processing of similar short message data and improve the encryption efficiency of subsequent short messages. Based on the data clustering results, this paper constructs a short message forwarding verification model using the SM9 identification password algorithm, and provides the message content of the communication application protocol and the communication receiving information protocol to achieve low‐cost and efficient forwarding verification. In addition, this article improves the initial value selection of Logistic chaotic mapping by coupling the tent map with coupled mapping lattice (CML) in the spatiotemporal chaos model to generate a chaotic initial value sequence, thereby expanding the key space, enhancing the ability to resist exhaustive attacks, enhancing the randomness of the generated key parameters, and optimizing the encryption effect of short messages. The experimental results show that the short message security authentication time of the technology proposed in this article is basically controlled within 25 ms, and the minimum forwarding delay is only 23.9 ms, which can effectively resist attacks and improve the security of Beidou communication.

Co-operative non-orthogonal multiple access networks: a survey

Purpose The purpose of this paper is to present an up-to-date survey on the non-orthogonal multiple access (NOMA) technique with co-operative strategy, a fast-evolving fifth-generation (5 G) technology. NOMA is used for serving many mobile users, both in power and code domains. This paper considers the power-domain NOMA, which is now discussed as NOMA. Design/methodology/approach The first part of the paper discusses NOMA-based cooperative relay systems using different relay strategies over different channel models. In various research works, the analytical expressions of many performance metrics were derived, measured and simulated for better performance of the NOMA systems. In the second part, a brief introduction to diversity techniques is discussed. The multiple input and multiple output system merged with cooperative NOMA technology, and its future challenges were also presented in this part. In the third part, the paper surveys some new conceptions such as cognitive radio, index modulation multiple access, space-shift keying and reconfigurable intelligent surface that can be combined with NOMA systems for better performance. Findings The paper presents a brief survey of diverse research projects being carried out in the field of NOMA. The paper also surveyed two different relaying strategies that were implemented in cooperative NOMA over different channels and compared several performance parameters that were evaluated and derived in these implementations. Originality/value The paper provides a scope for recognizable future work and presents a brief idea of the new techniques that can be united with NOMA for better performance in wireless systems.

Communication Network with Secure, Reputable Mobile Agent Structure

Abstract: The proposed multiphase security model for mobile agents appears to address a critical issue in their mainstream deployment. The use of symmetric key cryptography is a sensible choice for securing mobile agent code and data, as it is more efficient than asymmetric key cryptography. The focus on defending against a meet-in-the-middle attack is also appropriate, as this is a common type of attack that mobile agents are vulnerable to. However, it would be helpful to provide more details about the specific authenticated encryption mechanism that will be used. This will help to evaluate the effectiveness of the proposed model and ensure that it is robust enough to defend against various types of attacks. It is also important to consider the energy consumption of the proposed security model, as mobile devices typically have limited battery life. Therefore, the model should be designed in a way that minimizes energy consumption while maintaining the required level of security. Overall, the proposed multiphase security model appears to be a step in the right direction for addressing the security issues associated with mobile agents. However, it is important to ensure that it is properly implemented and thoroughly tested to ensure its effectiveness and efficiency

Cloud Based Bus Pass System

Abstract: The Real-Time Cloud-Based Bus Pass System Project serves as a convenient solution for commuters who are encountering difficulties with the current manual bus pass system. It allows passengers to travel easily with a mobile ticket QR code, which they can display if they lose their ticket during inspections. The QR code can be checked by the Train Ticket Examiner (TTE) and the system administrator to verify its authenticity. The system assigns a unique number to each passenger, preventing duplication. It also extends the validity period and sends timely alerts to the commuters through SMS or email before the expiry of their pass. Renewal or registration can be done using various payment methods, including credit or debit cards. Initially, passengers need to register with the application by submitting their personal details, including their photo and address proof, online. The system will review the information and approve or reject the bus pass application accordingly. Additionally, renewal can be performed using credit card or other payment methods.

Geochemical fractionation, mobility of elements and environmental significance of surface sediments in a Tropical River, Borneo

Miri River is a tropical river in Borneo that drains on flat terrain and urbanised area and debauches into the South China Sea. This paper documents the environmental status of this river, and provides an insight into the provenance using bulk chemistry of the sediments, and brings out the geochemical mobility, bioavailability, and potential toxicity of some critical elements based on BCR sequential extraction. The sediments are intense to moderately weathered and recycled products of Neogene sedimentary rocks. The hydrodynamic characteristics of the river favoured an upstream section dominated by fine sand, while the downstream sediments are medium silt. Based on the bulk geochemistry, the Miri River sediments are moderate to considerably contaminated by Cu, Mo, and As in the upstream and by Sb, As and Cu in the downstream. The potential ecological risk values are low except Cu and a significant biological impact is expected in downstream due to Cu, As, Zn and Cr. The mobility, bioavailability and Risk Assessment Code values for Zn and Mn are higher and thus may pose moderate to very high risk to aquatic organisms. Though a high bulk concentration of Cu is observed, the association of Cu with the bioavailable fraction is low.

Heavy Metals Speciation, Mobility, and Bioavailability in Constructed Wetland Sediment Treating Polluted River Water: Implication for Environmental Safety

The presence of toxic heavy metals in sediments beyond allowable limits are often posing a serious threat to local environment. Constructed wetland sediments contamined with heavy metals can affect sediment-dewlling biota such as benthic organisms, wetland plants, aquatic life including amphibian and reptiles. The objective of this study was to investigate heavy metals, mobility and bioavailability, level of environmental risks, and it implication for environmental safety. The study was conducted using the horizontal subsurface flow (HSSF) constructed wetland (CW) sediments designed for treating polluted Little Akaki River water. The sediment samples were collected from the CW and heavy metals speciation determined following the European Community Bureau References (BCR) sequential extraction procedures. The results showed that the highest percentage of metal fractions: Zn = 71.67%, Cr =82.20%, Cd = 76.47% and Pb = 74.96% were bound to residual fraction(R), implying that majority of the metals were stable, immobile and not bioavailable. The mobility factor (MF) for Zn (27.60%); Cr (14.24%) Cd (18.82% and Pb (21.53%); indicating low percentage of metals found in mobile chemical form. Furthermore, the environmental risk assessment code (RAC %) value for all heavy metals in the sediment samples were ranged: 5.37 % - 8.51%, falling in low risk category (RAC=1-10%). Low mobility, bioavailability and risk assessment code may be attributed to slight alkaline pH, low organic matter, and caly dominated sediment particles. High residual fraction occurred due to clay particles which can form strong bounding matrix with metals. Thus, metals in the CW sediments may pose low toxicity to wetland plants and sediment living biota surrounding environment.

Trimming Mobile Applications for Bandwidth-Challenged Networks in Developing Regions

Despite continuous efforts to build and update mobile network infrastructure, mobile devices in developing regions continue to be constrained by limited bandwidth. Unfortunately, this coincides with a period of unprecedented growth in the sizes of mobile applications. Thus it is becoming prohibitively expensive for users in developing regions to download and update mobile apps critical to their economic and educational development. Unchecked, these trends can further contribute to a large and growing global digital divide. Our goal is to better understand the source of this rapid growth in mobile app code size, whether it is reflective of new functionality, and identify steps that can be taken to make existing mobile apps more friendly to bandwidth constrained mobile networks. We hypothesize that much of this growth in mobile apps is due to poor resource/code management, and do not reflect proportional increases in functionality. Our hypothesis is partially validated by mini-programs, apps with extremely small footprints gaining popularity in Chinese mobile platforms. Here, we use functionally equivalent pairs of mini-programs and Android apps to identify potential sources of “bloat,” i.e., inefficient uses of code or resources that contribute to large package sizes. We analyze a large sample of popular Android apps and quantify instances of code and resource bloat. We develop techniques for automated code and resource trimming, and successfully validate them on a large set of Android apps. We hope our results will lead to continued efforts to streamline mobile apps, making them easier to access and maintain for users in developing regions.

Spatial management of air and missile defence operations

This paper relates to the accepted presentation presented at the international Air and Missile Defence Technology Conference, held on November 16–17, 2022, in London, the UK, (day two), reflecting the contents of the presentation slides. It describes applications of the patented and internationally tested Spatial Grasp Technology (SGT) and its Spatial Grasp Language (SGL) for integrated air and missile defense (IAMD). Based on holistic space navigation and processing by recursive mobile code self-spreading in distributed words, SGT differs radically from the traditional management of large systems since it consists of parts exchanging messages. The dynamic network of SGL interpreters can be arbitrarily large and cover terrestrial and celestial environments as powerful spatial engines. The paper contains an example of tracking and destruction of multiple cruise missiles by self-evolving spatial intelligence in SGL using networks of radar stations. It also briefs the growing multiple satellite constellation in low Earth orbits (LEO) for potential IAMD applications. Starting from the Strategic Defense Initiative (SDI) of the past and then briefing the latest project of the Space Development Agency, the paper shows SGL solutions for discovery, tracking, and destroying ballistic missiles and hypersonic gliders with the use of collectively behaving constellations of LEO satellites. It also shows how to organize higher levels of supervision of groups of mobile chasers fighting multiple targets (potentially both missiles and drones), by providing global awareness and even consciousness in SGL which can drastically improve their performance. The latest version of SGT can be implemented on any platform and put into operation in a short time, similar to its previous versions in different countries.

Mass vaccinations against COVID-19 through the use of technologies for the management of appointment scheduling and data of large volumes of vaccinated

Mass vaccination poses a challenge for health authorities due to the high volume of people who need to be vaccinated in a short period of time. Manual processes in vaccination centres to record and control vaccinations where the data is entered on paper result in delays in the timely input of information rendering the vaccination process inefficient. The proposed prototype, as a strategy for mass COVID-19 vaccination, to generate appointments, record, and control entry to vaccination centres, uses mobile technology, QR codes, and cloud computing to automate these data-driven processes. Technology-based processes help people by giving them the flexibility to choose the most convenient vaccination centre and provide health authorities with data-driven tools for management, control, and real-time decision-making.

Vacunaciones masivas contra el COVID-19 mediante el uso de las tecnologías para la gestión de programación de citas y de datos de grandes volúmenes de vacunados

Mass vaccination against COVID-19 using technologies to manage appointment scheduling and data in large volumes of vaccinated people Abstract Mass vaccination poses a challenge for health authorities due to the high volume of people who need to be vaccinated in a short period of time. Manual processes in vaccination centres to record and control vaccinations where the data is entered on paper result in delays in the timely input of information rendering the vaccination process inefficient. The proposed prototype, as a strategy for mass COVID-19 vaccination, to generate appointments, record, and control entry to vaccination centres, uses mobile technology, QR codes, and cloud computing to automate these data-driven processes. Technology-based processes help people by giving them the flexibility to choose the most convenient vaccination centre and provide health authorities with data-driven tools for management, control, and real-time decision-making.

Object Intersection Captures on Interactive Apps to Drive a Crowd-sourced Replay-based Compiler Optimization

Traditional offline optimization frameworks rely on representative hardware, software, and inputs to compare different optimizations on. With application-specific optimization for mobile systems though, the idea of a representative testbench is unrealistic while creating offline inputs is non-trivial. Online approaches partially overcome these problems but they might expose users to suboptimal or even erroneous code. Therefore, our mobile code is poorly optimized, resulting in wasted performance and energy and user frustration. In this article, we introduce a novel compiler optimization approach designed for mobile applications. It requires no developer effort, it tunes applications for the user’s device and usage patterns, and it has no negative impact on the user experience. It is based on a lightweight capture and replay mechanism. Our previous work [ 46 ] captures the state accessed by any targeted code region during its online stage. By repurposing existing OS capabilities, it keeps the overhead low. In its offline stage, it replays the code region but under different optimization decisions to enable sound comparisons of different optimizations under realistic conditions. In this article, we propose a technique that further decreases the storage sizes without any additional overhead. It captures only the intersection of reachable objects and accessed heap pages. We compare this with another new approach that has minimal runtime overheads at the cost of higher capture sizes. Coupled with a search heuristic for the compiler optimization space, our capture and replay mechanism allows us to discover optimization decisions that improve performance without testing these decisions directly on the user. Finally, with crowd-sourcing we split this offline evaluation effort between several users, allowing us to discover better code in less time. We implemented a prototype system in Android based on LLVM combined with a genetic search engine and a crowd-sourcing architecture. We evaluated it on both benchmarks and real Android applications. Online captures are infrequent and introduce ~5 ms or 15 ms on average, depending on the approach used. For this negligible effect on user experience, we achieve speedups of 44% on average over the Android compiler and 35% over LLVM -O3. Our collaborative search is just 5% short of that speedup, which is impressive given the acceleration gains. The user with the highest workload concluded the search 7 \( \times \) faster.

A REVIEW OF DIGITAL PAYMENT ADOPTION IN ASIA

Digital payments have changed people's financial behavior, particularly in Asian countries. The expansion of the internet network and the intensification of gadget functions have grown digital payment systems in mobile payments, internet banking, QR Codes, and electronic payments. Using a Systematic Literature Review, the study examined various Scopus articles from Asian countries to obtain an overview of the factors that influence the adoption of digital payments. We analyzed 597 digital, electronic, and mobile payment articles. TAM and UTAUT were found to be the most widely found theories to significantly affect user intent and even the continuity of digital payment use. While in the method, the structural equation model becomes the most widely used analytical method in various scientific publications related to this topic. This study has found internal and external factors from users in the adoption process of digital payments, including trust, perceived risk, satisfaction, security social influences, and facilitation conditions. Interestingly, some of these factors were insignificant in some studies due to differences in digital payment products that were the object of the study, respondents, and differences in research methods and approaches.

A programmable diffractive deep neural network based on a digital-coding metasurface array

The development of artificial intelligence is typically focused on computer algorithms and integrated circuits. Recently, all-optical diffractive deep neural networks have been created that are based on passive structures and can perform complicated functions designed by computer-based neural networks. However, once a passive diffractive deep neural network architecture is fabricated, its function is fixed. Here we report a programmable diffractive deep neural network that is based on a multi-layer digital-coding metasurface array. Each meta-atom on the metasurfaces is integrated with two amplifier chips and acts an active artificial neuron, providing a dynamic modulation range of 35 dB (from −22 dB to 13 dB). We show that the system, which we term a programmable artificial intelligence machine, can handle various deep learning tasks for wave sensing, including image classification, mobile communication coding–decoding and real-time multi-beam focusing. We also develop a reinforcement learning algorithm for on-site learning and a discrete optimization algorithm for digital coding. Using a multi-layer metasurface array in which each meta-atom of the metasurface acts as an active artificial neuron, a programmable diffractive deep neural network can be created that directly processes electromagnetic waves in free space for wave sensing and wireless communications.

Exploring Artificial Intelligence for Network Security: A Case Study of Malware Defence

AI has many applications in network security. Network security is one of the most challenging situations. The paper carries out AI based network security analysis and prevention ways of the deep learning models in the network security. We focus on some specific AI applications including voice supervision of public network, malicious code monitoring, smartphone intrusion monitoring, HTTP security monitoring, mobile phone malicious APK code monitoring are bringing the solutions for network security. We studied there are powerful methods such as mobile phone malicious APR code monitoring employed Artificial Neural Network (ANN) model which detects and mitigates predictable and unpredictable DDoS attacks (TCP, UDP, and ICMP protocols). HTTP is running over TCP, then the web server can face many TCP-related attacks, therefore, we have an experiment of HTTP security monitoring, mobile phone malicious APK code monitoring. This paper presents a potential security threats from malicious uses of AI, and proposes ways to better prevent, and mitigate these threats. When planning HTTP service protection, we present it is important to keep in mind that the attack surface is much broader than just the HTTP protocol. We suggest promising areas for further research that could expand the AI based solutions for development of cloud computing-related technologies, and the combination of cloud computing and deep learning technology in the security area.

An Adaptive Offloading Mechanism for Mobile Cloud Computing: A Niching Genetic Algorithm Perspective

The fast evolution of mobile applications demonstrates the growing need for more resources and processing power on mobile devices. Mobile Cloud Computing (MCC) combines cloud computing with mobile devices, enabling sophisticated and resource-intensive applications to operate on mobile devices regardless of their performance limits (e.g., battery life, memory utilization, and computation). Overcoming these constraints is accomplished using a well-known technique called computation offloading, which entails offloading heavy processing to resourceful servers and getting the results from these servers. Many studies have been done on mobile code offloading, with the goal of avoiding the stated limits and reducing execution time or battery consumption through single- or multiple-site offloading, so that people can use their phones and tablets more. However, the majority of existing techniques make offloading choices based on profile data, which implies a stable network environment and forces an object to be offloaded to the same site. As a consequence of these challenges, this research proposes a novel strategy for enhancing the multisite offloading mechanism by combining a Niching Genetic Algorithm (NGA) with a Markov Decision Process (MDP). MDP is used to determine the most optimal location for each application’s modules to be executed. GA was used to determine the optimal transition probability for components operating on several sites. To aid in initial population selection, the proposed model employs a niche model in the form of a context-based clearing (CBC) technique to improve the variability of the genes inside the chromosome in order to minimize their association. The simulation results reveal that the proposed technique consumes little power and executes quickly while determining the optimal offloading decision with lower generation numbers.

Management of Celestial Systems under Spatial Grasp Model

Many governmental agencies and private companies of different countries are now rushing into space around Earth in hope to provide smart communication, industrial, security, and defense solutions. This often involves massive launches of cheap small satellites which are also contributing to the growth of space debris. The current paper discusses how the developed high-level system philosophy and model can effectively organize distributed space-based systems on different stages of their development and growth. The briefed Spatial Grasp Technology, based on parallel pattern-matching of distributed environments with high-level recursive mobile code, can effectively provide any networking protocols and important applications of large satellite constellations, especially those on Low Earth Orbits. The paper contains examples of technology-based solutions for establishing basic communications between satellites, starting from their initial, often chaotic, launches and distributing and collecting data in the growing constellations with even unstable and rapidly changing connections between satellites. It describes how to organize and register networking topologies in case of predictable distances between satellites, and how the fixed networking structures can help in solving complex problems. The latter including those related to the new Space Development Agency multiple-satellite defense-oriented architecture and allowing for effective integration of its continuous earth custody observation and cooperative missile tracking and elimination layers, based on self-spreading mobile intelligence. Earlier versions of the technology, described in many papers, six books including, were prototyped and used in different countries, with the current one quickly implementable too, even in university-based environments.

Multiangle Patterned Photonic Films Based on CdS and SiO2 Nanoparticles for Bar Code Applications

This paper proposes a patterned material composed of two types of photonic crystals based on CdS and SiO2 nanoparticles. We combined the photonic crystals with poly(ethylene glycol) diacrylate (PEGDA) by nanoparticle self-assembly and UV curing and successfully formed a material containing the different photonic crystals. The material prepared contains two kinds of photonic crystals with different refractive indices, CdS and SiO2 nanoparticles, and due to the large difference in refractive indices of the two materials, the reflection wavelengths of the photonic crystals composed of the two materials also have disparities when the incident angle changes. Macroscopically, the structural colors of the two photonic crystals change with the change in incident angle. In response to this phenomenon, we designed a variety of applications based on a multiangle patterned photonic crystal film to achieve a variety of information storage functions by changing the incident angle and, through the angle change, to achieve lipstick logo, mobile phone bar code, and antipeeping keyboard applications.