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The number of devices connected to the Internet via mobile devices is increasing every day. The cost of mobile data over 3G and 4G networks is high in some countries, which pushes many users to browse the internet through text-only service. Facebook proposed a free basics service that allows users to browse Facebook for free but without showing images. This research formats the images on web pages using a method that transfers images over text-only networks. This will allow users with low income or slow connections to surf text service over the internet with images supported. The main objective is to test the free basics service by Facebook and Internet Service Provider over 3G networks, additionally proposing an image format for text-only networks. The proposed algorithm converts .png and .jpg images and posts them on the Facebook page. The results from the Facebook page show images that can be seen over 3G networks with the free mode enabled. [ABSTRACT FROM AUTHOR]

Clinics and hospitals have already adopted more technological resources to provide a faster and more precise diagnostic for patients, health care providers, and institutes of medicine. Security issues get more and more important in medical services via communication resources such as Wireless-Fidelity (Wi-Fi), third generation of mobile telecommunications technology (3G), and othermobile devices to connect medical systems from anywhere. Furthermore, cloud-basedmedical systems allow users to access archived medical images from anywhere. In order to protect medical images, lossless data hiding methods are efficient and easy techniques. In this paper, we present a data hiding of two-tier medical images based on histogram shifting of prediction errors. The median histogram shifting technique and prediction error schemes as the two-tier hiding have high capacity and PSNR in 16-bit medical images. [ABSTRACT FROM AUTHOR]

The article informs that Arcep has introduced data-based regulation which allows for more in-depth knowledge of the telecoms market thanks to the unit data of the operators. Topics inclide follow the deployment of fiber at the building calculate the mobile coverage by technology 2G, 3G, 4G and 5G operator; and cartographic information becomes a real democratic issue with elected officials, local authorities and even citizens linked to the computer processing of data.

The third generation Beidou navigation satellite system（BeiDou-3） officially started full-scale global services on July 31，2020. The Beidou satellites are designed to provide positioning, navigation and timing services, as well as certain specific functions, like local and global short message communication， satellite-based augmentation, precise point positioning and international search-and-rescue service. This paper introduces the functions of BeiDou-3 in terms of the design principles and new technologies that are integrated into the system. Some novel breakthroughs are particularly analyzed, including the satellite signal system， inter-satellite links, time and frequency standards, space-borne electronics, effective powers and overall automatic controls. Finally, the general design of satellites that specifically targets three kinds of orbits is reviewed. [ABSTRACT FROM AUTHOR]

Objectives: Detection of allergen-specific immunoglobulin E (sIgE) is important for the diagnosis of allergy. IgE sensitization is commonly demonstrated in vivo by skin prick testing (SPT), or in vitro utilizing automated systems. Recently, HYCOR® Biomedical launched its new system for allergen sIgE testing called the NOVEOS™ Immunoanalyzer. This study aims to evaluate the analytical performance of the NOVEOS system in a bi-center study at Philipps-University Marburg (Site-1) and Charité Medical University Berlin (Site-2), respectively. Methods: The analytical performance was evaluated based on the guidelines I/LA20-A3, EP5-A3, EP17-A2, EP6-A, EP7-A3, and EP9-A3 of the Clinical and Laboratory Standards Institute (CLSI). Results: The conducted repeatability and within-laboratory precision tests provided acceptable performance with 3.0%–11.9% coefficient of variation across both sites. The limit of blank (LoB) and limit of detection (LoD) were <0.1 kU/L at both centers. A within-parameter linearity for all tested allergens was reported at both sites. Of note, no significant interference was observed for high levels of biotin, methylprednisolone, diphenhydramine, omalizumab, or ranitidine. Method comparison between the NOVEOS calibration and the latest World Health Organization (WHO) reference standard showed good agreement at both sites. Conclusions: The results from the analytical performance of the NOVEOS allergen sIgE assay and instrument testing at both sites were comparable. Overall, a good precision and linearity as well as a detection limit <0.1 kU/L were observed, with minimal impact of common interfering substances on patient recoveries. The NOVEOS is calibrated to the latest WHO reference standard and adds benefits like a small sample size and para-magnetic microparticles that improve upon third-generation allergen sIgE assays' design and performance. [ABSTRACT FROM AUTHOR]

In this paper, IoT (Internet of Things) information technology has been widely applied to the supply chain risk management (SCRM). Firstly, the source of risks has been sorted out, the external and internal risks have been described in detail with the risk management of supply chain system. Secondly, the supply chain risk and case reasoning were mentioned. Finally, the work actively explored the supply chain risk management by the IoT information, such as 3G network, RFID and GPS. The research on SCRM based on IoT information contributes to the construction and improvement of supply chain informatisation. [ABSTRACT FROM AUTHOR]

While some unmanned aerial vehicles (UAVs) can operate with a given degree of autonomy (e.g., path following, obstacle avoidance, auto return, and other flight modes), many civilian drones have a safety pilot standby all the time for abnormal conditions. This is typically done within line-of-sight (LOS) due to regulations. While flying within LOS, radio frequency communication remains a popular alternative for retail pilots. For beyond line of sight operations, given the availability of cellular technologies, the UAV community has explored the possibility of using the cellular network instead, which could bring benefits such as an additional channel for control and telemetry, extension of range, and allowing the UAV to interact with cloud services while it flies, via a data connection. With the current prevalence of data supporting communication over 3G and 4G networks, the following representative technologies have been used for long-distance control—short message service (SMS), transmission control protocol (TCP), message queue telemetry transport (MQTT), and the so-called "protocol-independent" service PubNub. While the safety of drone flights is highly prioritized by regulators, the issue becomes even more highlighted when control commands are transmitted via cellular network channels (e.g., 4G long-term evolution, SMS) which can introduce time delays in communication chains and degrade pilot's ability to properly control UAVs. This article reviews common UAV communication protocols over cellular links and presents a technique for measuring and modeling delays over such channels. The quality-of-fit for the proposed models is measured for different communication protocols, short versus long-range communication, and different UAV operation modes. Finally, details are presented for a system that manipulates a drone via the cellular network and latency is measured for such system. [ABSTRACT FROM AUTHOR]

The scheduling synchronization problem in this paper is to obtain an optimal schedule by optimizing running time, departure time, dwell time and arrival time of the last train in urban rail transit networks. Operators are often faced with multiple conflicting requirements simultaneously such as high passenger's service quality and less cost, smooth transfer events and less passenger's travel time, and high accessibility and less operation time. Thus, researchers in this industry concentrate on utilizing operations and management decisions to solve the scheduling problem while balancing the service trade-offs. In this paper, we formulate a mixed integer programming approach for the last train schedule planning, and passengers benefit from smoother transfer in the form of maximizing the transfer synchronization events, while operators simultaneously can benefit with lower operation costs by minimizing the worst big difference between last trains. We propose an improved non-dominated sorting approach embedded in a genetic algorithm to obtain close-to-optimal solutions in a much shorter time for a sophisticated, real-world and large-scale Beijing subway network. Results demonstrate that significant service performance gains (76.33% for Just-missed, 32.01% for successful transfer, 15.39% for non-equity for last trains and 45.25% for variance indicators, etc.), which indicate the effectiveness of the proposed modeling framework and solution algorithm. The operator formulates an efficient schedule for the actual operation of the urban rail transit network by the proposed application method, and it also would be applicable to solving schedule problems among a large-scale network in other industries. [ABSTRACT FROM AUTHOR]

The understanding of the benefit risk profile, and relative effectiveness of a new medicinal product, are initially established in a circumscribed patient population through clinical trials. There may be uncertainties associated with the new medicinal product that cannot be, or do not need to be resolved before launch. Postlicensing or postlaunch evidence generation (PLEG) is a term for evidence generated after the licensure or launch of a medicinal product to address these remaining uncertainties. PLEG is thus part of the continuum of evidence development for a medicinal product, complementing earlier evidence, facilitating further elucidation of a product's benefit/risk profile, value proposition, and/or exploring broader aspects of disease management and provision of healthcare. PLEG plays a role in regulatory decision making, not only in the European Union but also in other jurisdictions including the USA and Japan. PLEG is also relevant for downstream decision‐making by health technology assessment bodies and payers. PLEG comprises studies of different designs, based on data collected in observational or experimental settings. Experience to date in the European Union has indicated a need for improvements in PLEG. Improvements in design and research efficiency of PLEG could be addressed through more systematic pursuance of Scientific Advice on PLEG with single or multiple decision makers. To date, limited information has been available on the rationale, process or timing for seeking PLEG advice from regulators or health technology assessment bodies. This article sets out to address these issues and to encourage further uptake of PLEG advice. [ABSTRACT FROM AUTHOR]

Universal Mobile Telecommunications System (UMTS), is the third generation (3G) of mobile communication which is based on the wideband code division multiple access (W-CDMA) radio access to provide bandwidth and spectral efficiency. Interference in 3G system is significantly lower compared to the preceded generations. However, it does not mean 3G is free from the issues associated with interferences, such as low signal quality and call drop. The interference level in UMTS can be measured by using the well-known parameter Received Total Wideband Power (RTWP). This parameter is affected by many factors such as number of the users connected to the system, combining second generation (2G) and 3G frequencies within the same geographical area, geographical causes (difference of Altitude), and hardware impairment. In this paper we intensively study how these factors affect the uplink interference level (i.e. RTWP value) in 3G system used by a particular telecommunications company, Asiacell company, Iraq. The obtained data shows that call drop is the most serious issue raised due to high value of RTWP in 3G system. We demonstrate that system enhancement, in terms of lower RTWP level, are obtained by adding second carrier to the sites, separating 2G band from 3G band using special filter, and optimizing the hardware components. [ABSTRACT FROM AUTHOR]

Currently, cellular networks both 3G and 4G are heavily overloaded due to increasing usage of mobile applications. Offloading mobile data traffic through opportunistic communications is one of promising solution to solve this problem. This has huge advantage over other kinds of offloading techniques like no extra cost, significant reduction of mobile traffic, high efficiency. As a case of study, we are focusing our investigation in opportunistic communication for optimizing target set selection problem. A new algorithm is proposed for generating target set which uses machine learning paradigm. Since, machine learning is an emerging sector in computer science with lots of potential; we integrated it with offloading procedure to achieve better performance in real world scenario. The efficiency of proposed method is measured by comparing it with other methods like Greedy, Heuristic and Random. A case study is conducted incorporating this approach and performance evaluation is done. It can be ensured from this comparison that the proposed algorithm outperforms its counterparts. [ABSTRACT FROM AUTHOR]

Background. Utilization of the widely used wearable sensor and smartphone technology for remote monitoring represents a healthcare breakthrough. This study aims to design a remote real-time monitoring system for multiple physiological parameters (electrocardiogram, heart rate, respiratory rate, blood oxygen saturation, and temperature) based on smartphones, considering high performance, autoalarm generation, warning transmission, and security through more than one method. Methods. Data on monitoring parameters were acquired by the integrated circuits of wearable sensors and collected by an Arduino Mega 250 R3. The collected data were transmitted via a Wi-Fi interface to a smartphone. A patient application was developed to analyze, process, and display the data in numerical and graphical forms. The abnormality threshold values of parameters were identified and analyzed to generate an autoalarm in the system and transmitted with data to a doctor application via a third-generation (3G) mobile network and Wi-Fi. The performance of the proposed system was verified and evaluated. The proposed system was designed to meet main (sensing, processing, displaying, real-time transmission, autoalarm generation, and threshold value identification) and auxiliary requirements (compatibility, comfort, low power consumption and cost, small size, and suitability for ambulatory applications). Results. System performance is reliable, with a sufficient average accuracy measurement (99.26%). The system demonstrates an average time delay of 14 s in transmitting data to a doctor application via Wi-Fi compared with an average time of 68 s via a 3G mobile network. The proposed system achieves low power consumption against time (4 h 21 m 30 s) and the main and auxiliary requirements for remotely monitoring multiple parameters simultaneously with secure data. Conclusions. The proposed system can offer economic benefits for remotely monitoring patients living alone or in rural areas, thereby improving medical services, if manufactured in large quantities. [ABSTRACT FROM AUTHOR]

Phone number is a unique identity code of a mobile subscriber, which plays a more important role in the mobile social network life than another identification number IMSI. Unlike the IMSI, a mobile device never transmits its own phone number to the network side in the radio. However, the mobile network may send a user's phone number to another mobile terminal when this user initiating a call or SMS service. Based on the above facts, with the help of an IMSI catcher and 2G man-in-the-middle attack, this paper implemented a practicable and effective phone number catcher prototype targeting at LTE mobile phones. We caught the LTE user's phone number within a few seconds after the device camped on our rogue station. This paper intends to verify that mobile privacy is also quite vulnerable even in LTE networks as long as the legacy GSM still exists. Moreover, we demonstrated that anyone with basic programming skills and the knowledge of GSM/LTE specifications can easily build a phone number catcher using SDR tools and commercial off-the-shelf devices. Hence, we hope the operators worldwide can completely disable the GSM mobile networks in the areas covered by 3G and 4G networks as soon as possible to reduce the possibility of attacks on higher-generation cellular networks. Several potential countermeasures are also discussed to temporarily or permanently defend the attack. [ABSTRACT FROM AUTHOR]

Patent quality (PQ) is a critical and complex factor of a firm's patent strategy. We posit that the existing PQ models and their methodological approaches are limited in their ability to address the multiple priorities of PQ – a firm's strategic intentions, its stakeholders and balancing technology superiority and legal validity. We advance PQ literature by identifying the fourth generation of strategic PQ indicators and propose a hybrid multi-criteria model, based on AHP–TOPSIS, for patent portfolio measurement. The proposed PQ model provides a simple template that can guide the decisions of patent managers pursuing high quality patent portfolios. We test the PQ model by applying it in two sectors: 3G WCDMA telecommunications and biotechnology. [ABSTRACT FROM AUTHOR]

Widespread computer science use and the tremendous changes in information and communication technologies (ICT) since the 2000s have induced major disruptions in the telecommunications sector. The Voice-Data–Image convergence had a significant effect on organizations, infrastructures and ICT platforms. Innovation has become a key value for this sector. However, the main weaknesses of telecom operators lie in the lack of their capacities to meet the requirements of continuous innovation. The aim of this article is to propose a critical reflection on the strategic orientations that the Algerian telecom operators can consider in the context of ICT convergence. A survey is conducted to understand the different developments in this sector and in particular to analyse the main issues faced by the incumbent operators and identify the growth levels in changing value chains. A particular reference to the experience of the incumbent operator of Algeria will be discussed from a transformation perspective strategy. [ABSTRACT FROM AUTHOR]

In this paper, we design and implement an Internet-of-Things (IoT) based platform for developing cities using environmental sensing as a driving application. Since ubiquitous and free WiFi access is not available in most developing cities, IoT deployments must leverage 3G cellular connections that are metered and expensive. In order to best utilize the limited 3G data plan, we propose two adaptation strategies to drive sensing and data collection. The first technique is an infrastructure-level adaptation approach where we adjust sensing intervals of periodic sensors so that the data volume remains bounded within the allocated data budget. The second approach is at the information-level where application-specific analytics are deployed on-board devices. This use case focuses on multimedia sensors that process captured raw media data to lower volume semantic data that is communicated. We implement the two adaptation strategies on the EnviroSCALE (Environmental Sensing and Community Alert Network) platform, which is an inexpensive Raspberry Pi based environmental sensing system that employs air quality sensors and periodically publishes sensor data over a 3G connection with a limited data plan. We outline our deployment experience of EnviroSCALE in Dhaka city, the capital of Bangladesh, particularly in the direction of infrastructure-level adaptation. For information-level adaptation, our testbed experiment results demonstrate the practicality of adaptive sensing and triggering rich sensing analytics via user-specified criteria over budgeted 3G connections. [ABSTRACT FROM AUTHOR]

Background: Third-generation sequencing platforms, such as PacBio sequencing, have been developed rapidly in recent years. PacBio sequencing generates much longer reads than the second-generation sequencing (or the next generation sequencing, NGS) technologies and it has unique sequencing error patterns. An effective read simulator is essential to evaluate and promote the development of new bioinformatics tools for PacBio sequencing data analysis. Results: We developed a new PacBio Sequencing Simulator (PaSS). It can learn sequence patterns from PacBio sequencing data currently available. In addition to the distribution of read lengths and error rates, we included a context-specific sequencing error model. Compared to existing PacBio sequencing simulators such as PBSIM, LongISLND and NPBSS, PaSS performed better in many aspects. Assembly tests also suggest that reads simulated by PaSS are the most similar to experimental sequencing data. Conclusion: PaSS is an effective sequence simulator for PacBio sequencing. It will facilitate the evaluation and development of new analysis tools for the third-generation sequencing data. [ABSTRACT FROM AUTHOR]

Service demand in cellular radio networks is generally heterogeneous and non uniform, leading to asymmetrical topologies. This complexity along with the multiple radio access technologies, the radio channel and practical constraints, make the radio network planning process a challenging task that leaves little room for intuitive solutions. In this paper we formulate the framework that allows for radio network planning analysis to be performed in the context of an evolutionary macro–micro-relay combination approach, or wide area microcell deployments. Coverage, capacity and cost requirements as well as different practical constraints such as reuse of existing 2G and 3G sites, are considered along with a multi-objective optimization algorithm adapted to the radio network planning problem for 4G systems. Among other things, the produced results highlight two key issues: (a) the way towards high capacity radio networks is to replace macrocells with a number of microcells that is more than one order of magnitude higher, (b) optimizing the radio network deployment can reduce the cost/Mbps/km2 by factors of 4 to 20, compared to equivalent macrocellular reference scenarios. [ABSTRACT FROM AUTHOR]

While steady-state solutions of backlog and delay have been derived for wireless systems, the analysis of transient phases still poses significant challenges. Considering the majority of short-lived and interactive flows, transient startup effects, as caused by sleep scheduling in cellular networks, have, however, a substantial impact on the performance. To facilitate reasoning about the transient behavior of systems, this paper contributes a notion of non-stationary service curves. Models of systems with sleep scheduling are derived and transient backlogs and delays are analyzed. Further, measurement methods that estimate the service of an unknown system from observations of selected probe traffic are developed. Fundamental limitations of existing measurement methods are explained by the non-convexity of the transient service and further difficulties are shown to be due to the super-additivity of network service processes. A novel two-phase probing technique is devised that first determines the shape of a minimal probe and subsequently obtains an accurate estimate of the unknown service. In a comprehensive measurement campaign, the method is used to evaluate the service of cellular networks with sleep scheduling (2G, 3G, and 4G), revealing considerable transient backlog and delay overshoots that persist for long relaxation times. [ABSTRACT FROM AUTHOR]

This paper presents a low-profile coplanar dual-polarized dual-band base station antenna array. A slotted patch antenna operating from 0.82 to 0.99 GHz with four shorting strips is proposed and analyzed. The four shorting strips are employed not only to improve the impedance matching in the lower band but also to remove the center part of the patch, thus making room for higher band dipoles operating from 1.68 to 2.86 GHz. The height of the proposed array is nearly half of the conventional base station array while other performances are guaranteed. The measured results show that the proposed antenna array has wide impedance bandwidths of 18.7% (0.82–0.99 GHz) and 57.9% (1.68–2.86 GHz) (VSWR < 2) with a low profile ($0.109\lambda _{0}$ at 820 MHz). The measured gains are 13.8±0.5 dB and 16.7 ± 1 dB in lower and upper bands. Large front-to-back ratio (>24.6 dB) and high isolations (>30 and >25 dB in lower and upper bands, respectively) are achieved. The proposed antenna can be easily built with printed circuit board fabrication technique and applied in low profile multiband base stations for 2G/3G/4G and the next-generation systems. [ABSTRACT FROM AUTHOR]

The bandwidth (BW) of a broadband dual-polarized antenna is enhanced for 2G/3G/4G systems and international mobile telecommunications services. The broadband dual-polarized element is a four-leaf clover antenna. By introducing a U-shaped slot to each leaf of the four-leaf clover and a parasitic element of four disks above the dual-polarized element, the BW enhancement is achieved. It is shown by simulation and experiment that the BW enhanced dual-polarized antenna achieves a BW of 67% (1.39–2.8 GHz) for reflection coefficients <−15 dB with an isolation (ISO) of 30 dB. An eight-element antenna array is developed for base station applications. The antenna array has a BW of about 70% (1.32–2.74 GHz) with an ISO of 25 dB. The antenna array achieves an average gain of ~17 dBi and a half-power beamwidth of 65 ± 5°, suitable for base station applications. [ABSTRACT FROM AUTHOR]

Well-deployed cellular networks offer a cheap wireless solution for the control channel deployment of Remote-Control Vehicles (RCV) and Unmanned Aerial Vehicles (UAV). However, a cellular data transfer service performance is affected by a different kind of User Equipment (UE) mobility. Operating conditions of UAV imply working at different altitudes, variable velocities with accelerations/decelerations and rapidly changed antennas angular position, which lead the wireless signal to be prone to negative effects. Available field measurement studies are not sufficient to provide excessive information on degradation problem causes for UEs moving along a complex trajectory. This paper presents an evaluation of the service quality of live operational 3G and LTE networks for both ground moving and flying UE. It has been found that antennas angular position variations in 3D (for example, during UAV manoeuvers) increase data transfer latency and jitter. Moreover, this effect in conjunction with higher interference at high altitudes may partially or fully block the data transfer service. This paper has been prepared to draw attention to the problem that makes the cellular data transfer service unusable for highly-manoeuvrable UAVs. [ABSTRACT FROM AUTHOR]