Mobile Application System Research Articles

5G Millimeter-Wave Antenna Array: Design and Challenges

As there has been an explosive increase in wireless data traffic, mmw communication has become one of the most attractive techniques in the 5G mobile communications systems. Although mmw communication systems have been successfully applied to indoor scenarios, various external factors in an outdoor environment limit the applications of mobile communication systems working at the mmw bands. In this article, we discuss the issues involved in the design of antenna array architecture for future 5G mmw systems, in which the antenna elements can be deployed in the shapes of a cross, circle, or hexagon, in addition to the conventional rectangle. The simulation results indicate that while there always exists a non-trivial gain fluctuation in other regular antenna arrays, the circular antenna array has a flat gain in the main lobe of the radiation pattern with varying angles. This makes the circular antenna array more robust to angle variations that frequently occur due to antenna vibration in an outdoor environment. In addition, in order to guarantee effective coverage of mmw communication systems, possible solutions such as distributed antenna systems and cooperative multi-hop relaying are discussed, together with the design of mmw antenna arrays. Furthermore, other challenges for the implementation of mmw cellular networks, for example, blockage, communication security, hardware development, and so on, are discussed, as are potential solutions.

Lay persons alerted by mobile application system initiate earlier cardio-pulmonary resuscitation: A comparison with SMS-based system notification

AimWe compared the time to initiation of cardiopulmonary resuscitation (CPR) by lay responders and/or first responders alerted either via Short Message Service (SMS) or by using a mobile application-based alert system (APP). MethodsThe Ticino Registry of Cardiac Arrest collects all data about out-of-hospital cardiac arrests (OHCAs) occurring in the Canton of Ticino. At the time of a bystander’s call, the EMS dispatcher sends one ambulance and alerts the first-responders network made up of police officers or fire brigade equipped with an automatic external defibrillator, the so called “traditional” first responders, and – if the scene was considered safe – lay responders as well. We evaluated the time from call to arrival of traditional first responders and/or lay responders when alerted either via SMS or the new developed mobile APP. ResultsOver the study period 593 OHCAs have occurred. Notification to the first responders network was sent via SMS in 198 cases and via mobile APP in 134 cases. Median time to first responder/lay responder arrival on scene was significantly reduced by the APP-based system (3.5 [2.8–5.2]) compared to the SMS-based system (5.6 [4.2–8.5] min, p 0.0001). The proportion of lay responders arriving first on the scene significantly increased (70% vs. 15%, p<0.01) with the APP. Earlier arrival of a first responder or of a lay responder determined a higher survival rate. ConclusionsThe mobile APP system is highly efficient in the recruitment of first responders, significantly reducing the time to the initiation of CPR thus increasing survival rates.

Service Mining for Trusted Service Composition in Cross-Cloud Environment

Nowadays, with the cloud's charismatic storage and computation power, more and more traditional services (social networking service, location-based services, etc.) are being migrated onto cloud platforms. These cloud services on different cloud platforms could be employed to form cross-cloud mobile applications of mobile cyber-physical systems (CPS). However, a cloud service may have various versions of quality of service (QoS) information revealed in different mobile CPS applications, which is often advertised as the elastic computation power. This characteristic makes it costly and time consuming to mine qualified ones from massive candidate cloud services for developing a mobile CPS application, as a service composition solution may have various evaluated values initiated by the various QoS properties. In view of this challenge, a cloud service selection method, named CSSM, is proposed in this paper. It takes the utility value as the evaluation index and aims at finding optimal or near-optimal trusted service composition solutions from a set of cloud services on users' demands. Technically, the user preference on each QoS metric is formalized as the preference interval for enhancing the fitness of a service composition solution. Furthermore, an extended top- $k$ iteration composition process is performed among cloud services to get an optimal or near-optimal trusted service composition solution. Both theoretical analysis and experimental evaluation are conducted to guarantee the feasibility and efficiency of the CSSM.

NAVIGATION OF MOBILE ROBOT- ALGORITHM FOR PATH PLANNING &amp; COLLISION AVOIDANCE- A REVIEW

The field of autonomous mobile robotics has recently gained many researchers’ interests. Due to the specific needs required by various applications of mobile robot systems, especially in navigation, designing a real time obstacle avoidance and path following robot system has become the backbone of controlling robots in unknown environments. The main objective of our project is applications based mobile robot systems, especially in navigation, designing real time obstacle avoidance and path following robot system has become the backbone of controlling robots in unknown environments. The main objective behind using the obstacle avoidance approach is to obtain a collision-free trajectory from the starting point to the target in monitoring environments. The ability of the robot to follow a path, detects obstacles, and navigates around them to avoid collision. It also shows that the robot has been successfully following very congested curves and has avoided any obstacle that emerged on its path. Motion planning that allows the robot to reach its target without colliding with any obstacles that may exist in its path.&#x0D; To avoid collision in the mobile robot environment, providing a path planning&amp; line following approach. Line following, path planning, collision avoidance, back propagation, improved memory, detecting long distance obstacles. Cheap and economical than the former one. Also work with back propagation technique.

Design and Voluntary Motion Intention Estimation of a Novel Wearable Full-Body Flexible Exoskeleton Robot

The wearable full-body exoskeleton robot developed in this study is one application of mobile cyberphysical system (CPS), which is a complex mobile system integrating mechanics, electronics, computer science, and artificial intelligence. Steel wire was used as the flexible transmission medium and a group of special wire-locking structures was designed. Additionally, we designed passive joints for partial joints of the exoskeleton. Finally, we proposed a novel gait phase recognition method for full-body exoskeletons using only joint angular sensors, plantar pressure sensors, and inclination sensors. The method consists of four procedures. Firstly, we classified the three types of main motion patterns: normal walking on the ground, stair-climbing and stair-descending, and sit-to-stand movement. Secondly, we segregated the experimental data into one gait cycle. Thirdly, we divided one gait cycle into eight gait phases. Finally, we built a gait phase recognition model based on k-Nearest Neighbor perception and trained it with the phase-labeled gait data. The experimental result shows that the model has a 98.52% average correct rate of classification of the main motion patterns on the testing set and a 95.32% average correct rate of phase recognition on the testing set. So the exoskeleton robot can achieve human motion intention in real time and coordinate its movement with the wearer.

Power sources involving ~ 300W PEMFC fuel cell stacks cooled by different media

Two constructions of ~300W PEMFC stacks, cooled by different media, were analysed. An open-cathode ~300W PEMFC stack cooled by air (Horizon, Singapore) and a PEMFC F-42 stack cooled by a liquid medium (Schunk, Germany) were chosen for all of the investigations described in this paper. The potential for the design and construction of power sources involving fuel cells, as well as of a hybrid system (fuel cell-lithium battery) for mobile and stationary applications, is presented and discussed. The impact of certain experimental parameters on PEMFC stack performance is analysed and discussed.

Wideband, Multiband, Tunable, and Smart Antenna Systems for Mobile and UWB Wireless Applications 2016

Wideband, Multiband, Tunable, and Smart Antenna Systems for Mobile and UWB Wireless Applications 2016

Ultrasensitive cellular fluorocarbon piezoelectret pressure sensor for self-powered human physiological monitoring

Flexible and wearable pressure sensors are of essential importance in developing artificial electronic skin (e-skin) for areas such as healthcare monitoring and clinical diagnosis. Here, we report an ultrasensitive cellular fluorocarbon piezoelectret pressure sensor (FPS) via a three-step hot-pressing method. By constructing micron-sized voids in the inner cell, and combination with outstanding charge storage ability of the fluorocarbon electrets, tremendous piezoelectric activity can be obtained. The flexible FPS showed advantages of remarkable sensitivity (7380pCN−1) in the subtle-pressure regime (<1kPa), fast response time (50ms), very low limit of detection (5Pa) as well as high stability (30,000 cycles). In addition, the flexible and self-powered FPS owns the capability for detecting human motions such as wrist stretching, cheek motion from open-bite-open, eyes blinking and chest respiration, respectively. It can be also used for monitoring human physiological signals such as radial artery pulse wave. By virtue of easy processability in large scale, light weight, and low cost, the FPS is especially suitable for mass production and flexible electronics, indicating their promising applications in artificial intelligence and mobile healthcare monitoring systems.

A Fixed-Point Neural Network Architecture for Speech Applications on Resource Constrained Hardware

Speech recognition and keyword detection are becoming increasingly popular applications for mobile systems. These applications have large memory and compute resource requirements, making their implementation on a mobile device quite challenging. In this paper, we design low cost neural network architectures for keyword detection and speech recognition. Wepresent techniques to reduce memory requirement by scaling down the precision of weight and biases without compromising on the detection/recognition performance. Experiments conducted on the Resource Management (RM) database show that for the keyword detection neural network, representing the weights by 5 bits results in a 6 fold reduction in memory compared to a floating point implementation with very little loss in performance. Similarly, for the speech recognition neural network, representing the weights by 6 bits results in a 5 fold reduction in memory while maintaining an error rate similar to a floating point implementation. Preliminary results in 40nm TSMC technology show that the networks have fairly small power consumption: 11.12mW for the keyword detection network and 51.96mW for the speech recognition network, making these designs suitable for mobile devices.

END-USER TRAINING ON DIGITAL TEACHING TOOLS: REACTION, LEARNING, BEHAVIOR, RESULTS, AND MANAGEMENT

The newly developed digital teaching tools, namely mobile class record application and portable learning management system were launched and distributed. This paper measures the evaluation rating of the region-wide end-user training on the classroom use and integration of the two digital teaching tools. A total of 74 trainees in Central Visayas, Philippines were trained. Using the New World Kirkpatrick Model, the trainees evaluated the training regarding reaction, learning, behavior, results, and management. The data show that the trainees rated the training with an overall mean of 3.70 described as “strongly agree.” The result implies that the end-user training on digital teaching tools is very successful and excellent.

Compact dual‐band BPF with wide stopband using stub‐loaded spiral stepped‐impedance resonator

A compact dual-band bandpass filter (BPF) with wide stopband performance using stub-loaded spiral short-circuit λ/4 stepped-impedance resonator is proposed. Spiral configuration has been used for compactness of filter. Both passbands can be controlled individually by changing the geometric parameters of resonator. Multiple transmission zeros provide high selectivity to both passband and extend stopband up to 3 GHz. The filter has compact size of 0.06λg × 0.09λg. A dual-band BPF has been designed and fabricated for terrestrial trunked radio (TETRA) band and global system for mobile communication applications.

Mutual authentications to parties with QR-code applications in mobile systems

User authentication over the Internet has long been an issue for Internet service providers and users. A good authentication protocol must provide high security and mutual authentication on both sides. In addition, it must balance security and usability, which has been shown in the literature to be a difficult problem. To solve this problem, we propose a novel mutual authentication protocol with high security and usability. The proposed protocol was developed for quick response code, a type of two-dimensional barcode that can be photographed and quickly decoded by smartphones. We implemented a prototype using the proposed mutual authentication protocol and demonstrated how the prototype improves usability in a mobile communication system. We also used the Gong---Needham---Yahalom logic with several well-known attack models to analyze the security of the proposed protocol, and we obtained satisfactory results. We expect that using the proposed protocol, Internet service providers will be able to provide a mutual authentication mechanism with high security and usability.

Editorial: Software Engineering and Applications for Cloud-Based Mobile Systems

Presents an editorial which explores the market fr cloud-based mobile computing systems. The concept of cloud-based mobile applications has emerged recently to address the limitations of pure mobile applications by leveraging the vast resources available at computing clouds. Traditionally, mobile applications benefit by outsourcing a part of the program execution to a cloud-based system to compute the (intermediate) results and send back these results for integration by the relevant mobile application. By doing so, the program code, data as well as device-specific information, such as user locations, can be made available to a cloud. Infrastructures to support computation outsourcing of the above type and its variants have been widely studied; and the associated security and privacy issues are hot topics in research.

A field survey system for land consolidation based on 3S and speech recognition technology

The main objective of this study is to develop a field survey system for land consolidation based on 3S (geographic information system, GIS; Global Positioning System, GPS; and remote sensing, RS) and speech recognition technology. Field survey in land consolidation is a complex and high-tech process. Traditional survey methods are difficult to use in locating, measuring, recording, and other related tasks. Through 3S and speech recognition technology, Android smart phones could address the aforementioned problems by providing a new method of land information collection. In this study, we present a land consolidation field survey system (LCFSS), which is developed on an Android mobile platform and integrates 3S and speech recognition technology to support the field survey of land consolidation. The proposed system is made advantageous by its low cost, high efficiency, portability, and user-friendliness. To improve the usability and feasibility of the LCFSS for decision making, we develop a data-adaptive development model, data compression model, three-parameter model for coordinate registration, and speech processing model. With the Unified Modeling Language, 5 functional modules and more than 16 application cases are described. On the basis of these models, the functions of system management, data import, project survey, coordinate registration, and data output are implemented by adopting the system architecture with four layers. The key achievement is tested and applied to a land consolidation survey in the provinces of Ningxia, Anhui, Shandong, and others. Results show that the efficiency of land information collection and other functions is improved with the use of the proposed system. Therefore, the approaches and methodology presented in this work could serve as a reference for those who are interested in developing mobile system applications based on 3S and speech recognition technology.

Dancing with Mobile Devices: The LAIT Application System in Performance and Educational Settings

ABSTRACTAt most any performance today, you will be notified to turn off your cell phone. The smartphone has become such an integral tool in our daily lives that turning it off is tantamount to severing our connection to our community and challenging the way we view and negotiate the world. Many audience members, particularly young ones, will be looking at their phones until the very last minute, sneaking peeks at social media throughout the performance. I decided several years ago to address this phenomenon by investigating how these devices could be integrated into live performance rather than battling against them. As a dance educator, I wanted to study this because as mobile devices become more and more necessary adjuncts to our existence, young artists and audiences will be seeking ways to integrate them into their theatrical expression. Recent classes, movement works, and technology ventures have explored the problem of how to weave the capabilities of mobile devices, and the possibilities that they present for both performers and audience, into the fabric of a successful dance theater work. This article first describes the investigative process through a creative dance class and performance of a dance called Kama Begata Nihilum. We then describe a technological solution in the form of a new mobile application system called Laboratory for Audience Interactive Technologies (LAIT) and recount more performance and teaching experiences using LAIT. Finally, we pose questions about the theory and use of ubiquitous digital devices in the dance theater of the twenty-first century and how this might affect thinking about future directions for teaching a new generation of young dance artists.

Design Estimations and Channel Capacity Calculations for Spatial, Polarized MIMO Antenna System for Mobile Applications

Design Estimations and Channel Capacity Calculations for Spatial, Polarized MIMO Antenna System for Mobile Applications

A new method for the assessment of traction enhancers and the generation of organic layers in a twin-disc machine

Low adhesion presents a major concern for many rail operators. Railway vehicles under these circumstances can experience a serious loss of braking capability giving rise to dangerous situations such as platform overruns and signals passed at danger. One cause of adhesion loss is autumn leaf fall, Fulford C.R. (2004) [1]. Leaves are run over by the wheels of a train and a chemical reaction occurs between the leaf and the rail steel, Cann P.M. (2006) [2]. This forms a black layer on the rail which when wet causes very low friction. These leaf layers have also been shown to be isolating and can interfere with railway signalling systems. Traction enhancers (also referred to in this paper as traction gels) have been developed as a new technique in combating the problems caused by leaf contamination. They consist of sand particles suspended in a water based gel and are designed to be delivered to the rail by the trackside or via mobile application systems. The aim of this work was to develop a technique for generating a representative leaf layer on the surface of a twin-disc rail specimen and using this to develop a test methodology for assessing the performance of a traction gel in terms of adhesion recovery, wear and its effect on wheel/rail isolation. A new repeatable method for generating a low traction leaf layer on the rail disc was developed. The traction gel tested was proven to quickly restore adhesion back to close to dry levels. The wear rate of the rail disc with the traction gel was lower than for a dry/uncontaminated contact. Isolation of the leaf layers and traction enhancer were measured using a representation of aTI21 track circuit. This method can be used in the selection and benchmarking of other traction enhancing products before they are trialed in the field.

Trajectory Planning and Collision Avoidance Algorithm for Mobile Robotics System

The field of autonomous mobile robotics has recently gained many researchers’ interests. Due to the specific needs required by various applications of mobile robot systems, especially in navigation, designing a real time obstacle avoidance and path following robot system has become the backbone of controlling robots in unknown environments. Therefore, an efficient collision avoidance and path following methodology is needed to develop an intelligent and effective autonomous mobile robot system. This paper introduces a new technique for line following and collision avoidance in the mobile robotic systems. The proposed technique relies on the use of low-cost infrared sensors, and involves a reasonable level of calculations, so that it can be easily used in real-time control applications. The simulation setup is implemented on multiple scenarios to show the ability of the robot to follow a path, detect obstacles, and navigate around them to avoid collision. It also shows that the robot has been successfully following very congested curves and has avoided any obstacle that emerged on its path. Webots simulator was used to validate the effectiveness of the proposed technique.

Development of an intelligent mobile robot localization system using Kinect RGB-D mapping and neural network

The most important issue of intelligent mobile robot development is to navigate autonomously in the environment for completing certain task demands. Nowadays, the Kinect sensor is affordable and popular for acquiring environment RGB image pixels with depth estimation. In this study, we focus on developing the indoor localization system for intelligent mobile robot applications. The innovation of this research is to combine the RGB-D mapping and neural network training for achieving an Indoor Positioning System. It is expected that the inputs are the robot’s observations of environmental features / landmarks and the direct output is the robot’s posture which will correspond to the RGB-D map. All the experimental results suggest that the robot’s posture and localization adjusts very efficiently with this study’s proposed method.

Validation Of Using A Mobile Application And Ankle-worn Accelerometers To Calculate Stance Time Asymmetry

Symmetry of loading during gait has been improved in individuals with amputations and joint replacements using an instrumented treadmill. However, this equipment is not readily available in clinics or at home where training typically occurs. Development of a cheaper, mobile system would allow for clinical adoption of these gait retraining techniques. PURPOSE: To determine the validity of calculating stance time asymmetry (STA) using a mobile application wirelessly connected to ankle-worn accelerometers. METHODS: A healthy male subject (35 yrs) walked on an instrumented treadmill for 30 seconds at 4 different speeds [1-1.6m/s] while varying between favoring his right side (RS), favoring his left side (LS), and normal (NL) walking. One 30 second trial of exclusive RS, LS, and NL walking were also collected at 1.2m/s. Accelerometers secured at both distal medial tibias streamed data via Bluetooth (approx. 500 Hz) to a mobile device. In real-time, a custom program on the mobile device calculated STA from the accelerometer data (AccelApp-based STA). Concurrently, treadmill force data (1500Hz) and foot markers were collected and used to calculate STA post-hoc (force-based STA). STA is the percent difference in stance time between successive right and left steps. RESULTS: 126 STAs were compared (Figure 1). STAs showed excellent agreement [Limits of Agreement (LOA): 1.3±5.3% (95% CI)] and were significantly correlated (r2=0.96, y=x+0.24%, p<0.0001 for intercept and slope). CONCLUSIONS: Based on this subject, STAs calculated with an ankle based accelerometer and mobile application system hold promise as a valid method to calculate STA. Additional subjects are currently being tested. Supported by BADER Consortium (DoD OR100017).