Portable Mobile Devices Research Articles

A Study of 4G and 5G Networks and its Impact on Mobile Technology

Users may now access the internet while on the move thanks to mobile cellular data networks. One of the hottest areas creating high-speed wireless networks with innovative technology is mobile wireless cellular communication. A radio network technology is a wireless mobile network. In the last 15 years, mobile wireless technology has skyrocketed. Nowadays, the most frequent mode of communication is through a mobile portable device. From the first generation to the fifth generation, wireless technology has been used in mobile communication. The fourth and fifth generations of mobile networks are discussed in this study. We examine the similarities and differences, as well as the advantages and disadvantages of each. We can see how 4G and 5G have influenced us across a variety of industries.

Study of Electrical Performance of Hetero-Dielectric Gate Tunnel Field Effect Transistor (HDG TFET): A Novel Structure for Future Nanotechnology

Although, dynamic power in portable mobile devices can be reduced by reducing power supply VDD on the cost of increased leakage current. Therefore, maintaining low leakage current in the device is serious issue for minimizing overall power consumption of the circuit and improving the battery life. The conventional Metal Oxide Field Effect Transistor (MOSFET) requires at least 60 mV of gate voltage for better current drive at room temperature which is difficult to achieve due to thermal limit. This limitation of gate voltage requirement degrades the performance of the device at lower VDD. Tunnel Field Effect Transistor (TFET) is a potential candidate to replace CMOS in deep-submicron region due to its lower subthreshold slope SS (< 60 mV/decade) at room temperature. Steep switching in TFET can extend the supply voltage scaling with improved energy efficiency for both digital and analog applications. Despite those advantages, TFETs are suffering from lower ON current and larger ambipolar current. To overcome these shortcomings, a new structure, known as Hetero-dielectric gate TFET (HDG TFET), has been proposed in the literature. Since, in the absence of the compact analytical model, it is difficult to understand the electrical behaviour of the HDG TFET device, therefore, the present paper presents an analytical model of transconductance parameter of HDG TFET device. The electrical performance analysis of HDG TFET device reflects that on current can be increased considerably by choosing gate material of higher work function near the source region which also suppresses the ambipolar current. It is also observed that a thinner silicon film and larger drain bias result in larger transconductance value.

Real-Time Collection and Analysis of Sports Index Time Series Based on Multimodal Sensor Monitoring

With the further development of microelectronics technology and sensors, sensors can be widely embedded in mobile phone devices and portable devices. The use of acceleration sensors for human motion monitoring has broad application prospects. Monitoring the daily exercise of the human body is of great significance for formulating scientific exercise and fitness plans and improving physical health. This paper uses the measurement data of multiple types of sensors to propose an index recognition method based on the fusion of multiple types of sensor information. We take the measurement value of a single type of sensor as input and output the index value of the moving part without a strain sensor. The pattern recognition method is used to establish a pattern library, a recognition library, and a measurement library. This article considers noise interference or malfunction of sensor measurements. Aiming at uncertain factors such as the error of the finite element model, a pattern matching method considering the uncertainty is proposed. This article takes aerobics as an example to simulate and analyze the dynamic response of aerobics under wind load. In addition, by simulating the recognition results under different levels of noise interference, the robustness and anti-interference of the pattern matching method are verified.

Image and Text Encrypted Data with Authorized Deduplication in Cloud

In this study, role re-encryption is employed in a secure role re-encryption system to minimize data leakage and deduplication. It also looks for evidence of ownership to see whether the user is an authorized one. This is for the sake of effectiveness. The role re-encryption approach involves sharing the access key for the associated authorized user in order to access a specific file without exposing personal information. We use both the avoid use of text and digital visuals in our endeavour. Personal photographs, for example, are stored on our mobile phones, portable devices, computers, and other gadgets. As these photographs must be kept confidential, we are encrypting them. Nowadays, the text file is equally significant for users. It must be kept safe on a cloud server. Digital photographs must be safeguarded during transmission, but personal identity information such as copies of a pan card, passport, ATM card, and so on, should be stored on a single wnpc. To minimize duplication in our proposed system, we are securing the text file and picture data.

An improved low-complexity DenseUnet for high-accuracy iris segmentation network

Iris segmentation is one of the most important steps in iris recognition. The current iris segmentation network is based on convolutional neural network (CNN). Among these methods, there are still problems with the segmentation networks such as high complexity, insufficient accuracy, etc. To solve these problems, an improved low complexity DenseUnet is proposed to this paper based on U-net for acquiring a high-accuracy iris segmentation network. In this network, the improvements are as follows: (1) Design a dense block module that contains five convolutional layers and all convolutions are dilated convolutions aimed at enhancing feature extraction; (2) Except for the last convolutional layer, all convolutional layers output feature maps are set to the number 64, and this operation is to reduce the amounts of parameters without affecting the segmentation accuracy; (3) The solution proposed to this paper has low complexity and provides the possibility for the deployment of portable mobile devices. DenseUnet is used on the dataset of IITD, CASIA V4.0 and UBIRIS V2.0 during the experimental stage. The results of the experiments have shown that the iris segmentation network proposed in this paper has a better performance than existing algorithms.

ARMOR: A Reliable and Mobility-Aware RPL for Mobile Internet of Things Infrastructures

Mobile portable embedded devices are becoming an integral part of our daily activities in the vision of Internet of Things (IoT). Nevertheless, due to lack of mobility support in the IPv6 routing protocol for low-power and lossy networks (RPLs), which is standardized for multihop IoT infrastructures, providing reliable communications in terms of packet delivery ratio (PDR) in mobile IoT applications has become significantly challenging. While several studies tried to enhance the adaptability of RPL to network dynamics, their utilized routing metrics have prevented them from establishing long-lasting reliable paths. Furthermore, the stochastic parent replacement policy in the standard version of RPL has intensified this challenge. Aside from this, due to the existing tradeoff between reliability and power efficiency, most of the existing approaches have only concentrated on one of these concerns without paying attention to the other one. To address these issues, this article introduces ARMOR, a routing mechanism built upon RPL, which employs a novel mobility-aware routing metric, i.e., time to reside (TTR), and a corresponding parent replacement policy. According to the motion characteristics of the mobile objects, TTR provides an estimation of how long the nodes will be in the transmission range of each other. This enables ARMOR to select nodes, which provide longer connection period and consequently higher reliability. In comparison with the state of the art, while keeping the power consumption constant, ARMOR significantly improves the amount of PDR in the network by up to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2.5\times $ </tex-math></inline-formula> , while it enhances the reliability against the original version of this protocol by up to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$4.2\times $ </tex-math></inline-formula> .

THE OPPORTUNITIES OF MOBILE TECHNOLOGIES IN THE PRACTICE OF TEACHING THE UKRAINIAN LANGUAGE AS A FOREIGN LANGUAGE

The article deals with the problem of forming a linguistic personality of foreign medical students. The article highlights the problem of forming the language personality of a foreign medical education seeker in the context of changes in the world and domestic educational systems. The authors analyze the relevance and appropriateness of using mobile technologies in Ukrainian language classes as a foreign language, taking into account the modern development of society, organizational and technological foundations of studying the subject «Ukrainian as a Foreign Language». Considering the trend of transition of users from the operation of desktop personal computers to more mobile portable devices (tablets, smartphones) and based on the problems of organizing the educational process, the assumption of the effectiveness and relevance of mobile technology in teaching Ukrainian as a foreign language. Based on the analysis of the existing definitions of the term "mobile learning" the interpretation was offered, in which mobile devices are the means to achieve didactic objectives. The potential of the use of mobile technologies in education is analysed, as well as the factors that complicate their applications by teachers are given. The domestic experience of using mobile devices for educational purposes is considered. The authors argue that there are many opportunities to transfer information materials to the learner. Options for using mobile learning in Ukrainian as a foreign language classes are shown. The article proposes the use of smartphones when performing practical tasks; target platforms in the study of topics; independent language acquisition; when repeating the material in extracurricular time. The advantages of using mobile devices as convenient tools for accessing cloud services to organize joint activities of students are considered.

THE USE OF QR-CODES IN PROFESSIONAL TRAINING OF STUDENTS OF ENVIRONMENTAL AND EDUCATIONAL INDUSTRIES

The article emphasizes the significance of the information and digital competence of teachers, which includes the ability to navigate in the information and digital space, the search and critical analysis of information, the use of educational electronic resources and creation of new ones, the use of digital technologies in the educational process. It notes that Digital Competence of Educators the European framework identifies six main areas of application: professional involvement; digital resources; teaching and learning; evaluation; promoting students' digital competence.&#x0D; The article reveals the importance of the m-learning implementation. It is the use of mobile technology in the educational process, the use of a wide range of digital portable mobile devices and applications. The best pedagogical experience in the implementation of mobile learning on the example of the use of QR codes is summarized. The main resources for creating and reading QR codes, examples of their use in educational activities are highlighted.&#x0D; Our own experience of using QR codes in the professional training of future biologists and teachers of natural sciences has been revealed. In particular, it is used in the Museum of Nature of Zhytomyr Ivan Franko State University to expand the museum's capabilities, the application of its exposition for educational excursions, independent work of students, to organize quests and educational games and more. The stages of projects using QR codes are described: the digital guide "Dendrological Secrets of Chaudoir Park" (the mayor grant for gifted youth) and "Digital Dendrological Guide of Zhytomyr" (the project of social action "Strengthening Intersectoral Cooperation for Social Cohesion", co-financed by the European Union and the British Council in Ukraine). Their implementation contributes to the creation of information space for Biology lessons, open-air Ecology, classes of ecological and naturalistic circles, botanical, biogeographical, ecological excursions, development of hiking tourism, etc.

A shorting-pin based compact meander multiband printed monopole antenna

The antenna presented in this work is based on a meandering monopole patch antenna with the incorporated shorting-pin technique for the realization of multiband antenna. The proposed antenna is printed on an FR4 with a footprint of 0.22λg×0.36λg at the lowest operating frequency. The antenna proposed demonstrated six resonances with suitable bandwidth as well as gain which make it suitable for WiMAX, LTE-A, aeronautical radio navigation, sub6GHz band for 5G, and WLAN applications. The prototype of the proposed antenna is fabricated, measured, and presented. The comparative analysis of the proposed antenna with the recently reported works shows that the proposed antenna outperformed its counterpart in terms of size and number of bands. Therefore, the antenna reported in this work is a suitable and promising candidate for future portable mobile communication devices.

The International Electrotechnical Commission standard will help assess the impact of a smartphone on humans

Accurate and reproducible testing of mobile devices to estimate specific absorption rate (SAR) levels requires the use of appropriate instruments and measurement methods in a standardized manner. They will help assess the impact that modern portable mobile devices can have on the human body.

A Routing Query Algorithm Based on Time-Varying Relationship Group in Opportunistic Social Networks

With the fast development of IoT and 5G technologies, opportunity social networks composed of portable mobile devices have become a hot research topic in recent years. However, arbitrary node movement in opportunity networks and the absence of end-to-end pathways make node communication unstable. At the same time, the problem of ignoring human social preferences and relying on wrong message relay nodes lead to a low data transmission rate and high network overhead. Based on the above issues, we propose a time-varying relationship groups-based routing query algorithm for mobile opportunity networks (Time-varying Relationship Groups, TVRGs). Firstly, we construct the relationship groups based on the time-varying characteristics according to the intimacy between users. Secondly, we calculate the importance of nodes by their connectivity time and communication frequency. Finally, we find the suitable message relay nodes according to the similarity of node weights and their action trajectories and design the routing query algorithm accordingly. The simulation results show that the algorithm can vastly improve the message query success rate, effectively improve the data transmission efficiency, and reduce the average delay and system overhead compared with the existing routing algorithms.

A Secure Truth Discovery for Data Aggregation in Mobile Crowd Sensing

With the rapid development of portable mobile devices, mobile crowd sensing systems (MCS) have been widely studied. However, the sensing data provided by participants in MCS applications is always unreliable, which affects the service quality of the system, and the truth discovery technology can effectively obtain true values from the data provided by multiple users. At the same time, privacy leaks also restrict users’ enthusiasm for participating in the MCS. Based on this, our paper proposes a secure truth discovery for data aggregation in crowd sensing systems, STDDA, which iteratively calculates user weights and true values to obtain real object data. In order to protect the privacy of data, STDDA divides users into several clusters, and users in the clusters ensure the privacy of data by adding secret random numbers to the perceived data. At the same time, the cluster head node uses the secure sum protocol to obtain the aggregation result of the sense data and uploads it to the server so that the server cannot obtain the sense data and weight of individual users, further ensuring the privacy of the user’s sense data and weight. In addition, using the truth discovery method, STDDA provides corresponding processing mechanisms for users’ dynamic joining and exiting, which enhances the robustness of the system. Experimental results show that STDDA has the characteristics of high accuracy, low communication, and high security.

A review of g-C3N4 based catalysts for direct methanol fuel cells

Direct methanol fuel cells (DMFC) possess numerous advantages for powering portable mobile devices. However, there are still major challenges in their development and commercialization that originates from the anode catalyst responsible for methanol oxidation reaction. This has motivated researchers to find a cost effective and durable catalyst material for methanol oxidation. Recently, carbon-based 2-D graphitic carbon nitride (g-C3N4) has been found to have good potentials to catalyse alcohol oxidation reactions in fuel cells. This review provides a summarized information of previously developed g-C3N4-containing-electrocatalysts based on the active sites present (e.g., non-metals, noble metals, and non-noble metals) for methanol electro-oxidation to compare their electrocatalytic performance. It also consists of brief examination of their structure, description of different synthesis methods and post-synthesis treatments, and evaluation of their properties that contributes to their resulting performance. The review then concludes with the details of challenges and possible solutions that enable DMFC to be a reliable source of energy in the future.

Low-Asymmetry Interface for Multiuser VR Experiences with Both HMD and Non-HMD Users.

We propose a low-asymmetry interface to improve the presence of non-head-mounted-display (non-HMD) users in shared virtual reality (VR) experiences with HMD users. The low-asymmetry interface ensures that the HMD and non-HMD users’ perception of the VR environment is almost similar. That is, the point-of-view asymmetry and behavior asymmetry between HMD and non-HMD users are reduced. Our system comprises a portable mobile device as a visual display to provide a changing PoV for the non-HMD user and a walking simulator as an in-place walking detection sensor to enable the same level of realistic and unrestricted physical-walking-based locomotion for all users. Because this allows non-HMD users to experience the same level of visualization and free movement as HMD users, both of them can engage as the main actors in movement scenarios. Our user study revealed that the low-asymmetry interface enables non-HMD users to feel a presence similar to that of the HMD users when performing equivalent locomotion tasks in a virtual environment. Furthermore, our system can enable one HMD user and multiple non-HMD users to participate together in a virtual world; moreover, our experiments show that the non-HMD user satisfaction increases with the number of non-HMD participants owing to increased presence and enjoyment.

Development and Verification of a System to Support Cooperative Learning Based on Peer Review by Visual Video Annotation on Portable Mobile Device

Development and Verification of a System to Support Cooperative Learning Based on Peer Review by Visual Video Annotation on Portable Mobile Device

Diversifying Inference Path Selection: Moving-Mobile-Network for Landmark Recognition.

Deep convolutional neural networks have largely benefited computer vision tasks. However, the high computational complexity limits their real-world applications. To this end, many methods have been proposed for efficient network learning, and applications in portable mobile devices. In this paper, we propose a novel Moving-Mobile-Network, named M2Net, for landmark recognition, equipped each landmark image with located geographic information. We intuitively find that M2Net can essentially promote the diversity of the inference path (selected blocks subset) selection, so as to enhance the recognition accuracy. The above intuition is achieved by our proposed reward function with the input of geo-location and landmarks. We also find that the performance of other portable networks can be improved via our architecture. We construct two landmark image datasets, with each landmark associated with geographic information, over which we conduct extensive experiments to demonstrate that M2Net achieves improved recognition accuracy with comparable complexity.

Exploring Optimized Hadamard Methods to Design Energy-Efficient SATD Architectures

State-of-the-art video coding tools are submitted to severe performance and energy consumption requirements resulting from high complexity of video standards and from limited energy budgets of portable mobile devices. While providing most of the compression gains, inter frame and intra frame prediction techniques are the most demanding steps, since they compare a huge number of blocks. In such a process, the similarity metric employed affects both the quality of compression and the calculation effort. In this paper we propose the use of Hadamardbased Sum of Absolute Transformed Differences (SATD), in replacement of the traditionally used Sum of Absolute Differences (SAD), as a means of improving the efficiency of video coding. To allow that we explore two Hadamard Transform methods to design efficient SATD architectures, one using the Fast Hadamard Transform (FHT) butterfly and another one using the so-called Transform-Exempted (TE) SATD algorithm. Those methods were combined with architectural decisions (full parallelism, full parallelism with pipelining or multi-cycling) to build a total of six Hadamard-based SATD architectures that were synthesized for a commercial 45nm standard cell library for two operating frequencies. The architectures were simulated with pixel block data to obtain realistic dynamic power and energy estimates. The TE-SATD architectures achieved the lowest energy results: down to 13.13 pJ/SATD in the case of parallel architecture with pipeline. However, considering also the area results when evaluating energy, the best results are given by both methods using multi-cycling (transpose buffer): nearly 20.75 pJ/SATD with up to 63.54% smaller area compared with fully parallel architectures.

An independent three‐factor mutual authentication and key agreement scheme with privacy preserving for multiserver environment and a survey

SummaryIn the past decades, the demand for remote mutual authentication and key agreement (MAKA) scheme with privacy preserving grows rapidly with the rise of the right to privacy and the development of wireless networks and Internet of Things (IoT). Numerous remote MAKA schemes are proposed for various purposes, and they have different properties. In this paper, we survey 49 three‐factor–based remote MAKA schemes with privacy preserving from 2013 to 2019. None of them can simultaneously achieve security, suitability for multiserver environments, user anonymity, user untraceability, table free, public key management free, and independent authentication. Therefore, we propose an efficient three‐factor MAKA scheme, which achieves all the properties. We propose a security model of a three‐factor–based MAKA scheme with user anonymity for multiserver environments and formally prove that our scheme is secure under the elliptic curve computational Diffie‐Hellman problem assumption, decisional bilinear Diffie‐Hellman problem assumption, and hash function assumption. We compare the proposed scheme to relevant schemes to show our contribution and also show that our scheme is sufficiently efficient for low‐power portable mobile devices.

Quality evaluation of HPV vaccine-related online messages in China: a cross-sectional study

ABSTRACT Since 2019, three types of HPV vaccine have been approved for use in mainland China. High quality messages are crucial for vaccine acceptance, but little is known about the online information quality concerning HPV vaccine in China. “HPV vaccine” and “cervical cancer vaccine” in the form of Chinese were used as keywords through search engines from personal computer (PC), portable mobile device (PMD), and WeChat Public Accounts in 2019. Readability, information content, as well as DISCERN scores were evaluated for each message included. Characteristics associated with quality indicators of the messages were also analyzed. A total of 294 messages from PC engines (104, 35%), PMD engines (128, 43%) and WeChat (62, 21%) were assessed. Most (269, 91%) messages required at least undergraduate readability level. The most frequently reported theme was HPV vaccine and its function (273, 93%), while the least was information regarding quality, safety and side effects (129, 44%). The frequency of messages with at least one error was 132 (45%). The median of sum DISCERN scores was 42 (IQR = 14), and only one (< 1%) message showed good DISCERN quality. Messages retrieved from PC engines and those with pictures were of better overall quality. The overall quality of HPV vaccine-related online messages in Chinese websites was not optimal. Government and health professionals should promote information quality construction to improve the status of HPV vaccination messages online.

Smartphone-based Fluoride-specific Sensor for Rapid and Affordable Colorimetric Detection and Precise Quantification at Sub-ppm Levels for Field Applications

Higher levels of fluoride (F–) in groundwater constitute a severe problem that affects more than 200 million people spread over 25 countries. It is essential not only to detect but also to accurately quantify aqueous F– to ensure safety. The need of the hour is to develop smart water quality testing systems that would be effective in location-based real-time water quality data collection, devoid of professional expertise for handling. We report a cheap, handheld, portable mobile device for colorimetric detection and rapid estimation of F– in water by the application of the synthesized core–shell nanoparticles (near-cubic ceria@zirconia nanocages) and a chemoresponsive dye (xylenol orange). The nanomaterial has been characterized thoroughly, and the mechanism of sensing has been studied in detail. The sensor system is highly selective toward F– and shows unprecedented sensitivity in the range of 0.1–5 ppm of F–, in field water samples, which is the transition regime, where remedial measures may be needed. It addresses multiple issues expressed by indicator-based metal complexes used to determine F– previously. Consistency in the performance of the sensing material has been tested with synthetic F– standards, water samples from F– affected regions, and dental care products like toothpastes and mouthwash using a smartphone attachment and by the naked eye. The sensor performs better than what was reported by prior works on aqueous F– sensing.