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Experiments are a commonly used method of research in software engineering (SE). Researchers report their experiments following detailed guidelines. However, researchers do not, in the field of test-driven development (TDD) at least, specify how they operationalized the response variables and, particularly, the measurement process. This article has three aims: (i) identify the response variable operationalization components in TDD experiments that study external quality; (ii) study their influence on the experimental results; (iii) determine if the experiment reports describe the measurement process components that have an impact on the results. We used two-part sequential mixed methods research. The first part of the research adopts a quantitative approach applying a statistical analysis of the impact of the operationalization components on the experimental results. The second part follows with a qualitative approach applying a systematic mapping study (SMS). The test suites, intervention types and measurers have an influence on the measurements and results of the statistical analysis of TDD experiments in SE. The test suites have a major impact on both the measurements and the results of the experiments. The intervention type has less impact on the results than on the measurements. While the measurers have an impact on the measurements, this is not transferred to the experimental results. On the other hand, the results of our SMS confirm that TDD experiments do not usually report either the test suites, the test case generation method, or the details of how external quality was measured. A measurement protocol should be used to ensure that the measurements made by different measurers are similar. It is necessary to report the test cases, the experimental task and the intervention type in order to be able to reproduce the measurements and statistical analyses, as well as to replicate experiments and build dependable families of experiments. [ABSTRACT FROM AUTHOR]

Abstract In this article an 8-port annular ring-shaped MIMO antenna for 5G and 5G advanced applications is presented. An annular ring on the radiating plane and novel isolator structure on the ground plane are etched over a Rogers RT/Duorid (5870 tm) substrate to achieve high performance antenna for mm wave applications. A systematic study is performed, and an optimized single port antenna (Design-4) is selected among Designs (1-4). The intended 8-port MIMO antenna resonates at 36.4 GHz and exhibits 6.1 GHz (34.2-40.3 GHz) wide bandwidth $$|S_{11}| < -10 \, \text {dB}$$ and 40 dB high isolation level. The proposed antenna covers a complete band of 5G NR-n260 which supports time division duplexing (TDD) mode. Moreover, a unique design of suggested antenna attains a high-level gain of 8.3 dB at 39 GHz and more than 85.2 % radiation efficiency. MIMO characteristics such as ECC, TARC, MEG and CCL are studied and found them in acceptable limit. Additionally, an approach toward massive antenna with 16-port for mmWave applications is also demonstrated. The proposed 16-port massive antenna with more than 22 dB isolation exhibits two bands: first band in 30-33 GHz for ports P9-P16 and second band in 33.5-40.9 GHz for ports P1-P8. A prototype of suggested 8-port antenna is fabricated, tested and validated and found it in close agreement of simulated results.

In this article an 8-port annular ring-shaped MIMO antenna for 5G and 5G advanced applications is presented. An annular ring on the radiating plane and novel isolator structure on the ground plane are etched over a Rogers RT/Duorid (5870 tm) substrate to achieve high performance antenna for mm wave applications. A systematic study is performed, and an optimized single port antenna (Design-4) is selected among Designs (1-4). The intended 8-port MIMO antenna resonates at 36.4 GHz and exhibits 6.1 GHz (34.2-40.3 GHz) wide bandwidth and 40 dB high isolation level. The proposed antenna covers a complete band of 5G NR-n260 which supports time division duplexing (TDD) mode. Moreover, a unique design of suggested antenna attains a high-level gain of 8.3 dB at 39 GHz and more than 85.2 % radiation efficiency. MIMO characteristics such as ECC, TARC, MEG and CCL are studied and found them in acceptable limit. Additionally, an approach toward massive antenna with 16-port for mmWave applications is also demonstrated. The proposed 16-port massive antenna with more than 22 dB isolation exhibits two bands: first band in 30-33 GHz for ports P9-P16 and second band in 33.5-40.9 GHz for ports P1-P8. A prototype of suggested 8-port antenna is fabricated, tested and validated and found it in close agreement of simulated results. [ABSTRACT FROM AUTHOR]

Densely distributed sensor networks can revolutionize environmental observations by providing real-time data with an unprecedented spatiotemporal resolution. However, field deployments often pose unique challenges in terms of power provisions and wireless connectivity. We present a framework for wirelessly connected distributed sensor arrays for near-surface temperature and/or deformation monitoring. Our research focuses on a novel time division duplex implementation of the LoRa protocol, enabling battery powered base stations and avoiding collisions within the network. In order to minimize transmissions and improve battery life throughout the network, we propose a dedicated delta encoding algorithm that utilizes the spatial and temporal similarity in the acquired data sets. We implemented the developed technologies in a AA battery powered hardware platform that can be used as a wireless data logger or base station, and we conducted an assessment of the power consumption. Without data compression, the projected battery life for a data logger is 4.74 years, and a wireless base stations can last several weeks or months depending on the amount of network traffic. The delta encoding algorithm can further improve this battery life with a factor of up to 3.50. Our results demonstrate the viability of the proposed methods for low-power environmental wireless sensor networks.

Auxiliary functions in software systems, often overlooked due to their perceived simplicity, play a crucial role in overall system reliability. This study focuses on the effectiveness of agile practices, specifically the pair programming and the test-first programming practices. Despite the importance of these functions, there exists a dearth of empirical evidence on the impact of agile practices on their development, raising questions about their potential to enhance correctness without affecting time-to-market. This paper aims to bridge this gap by comparing the application of agile practices with traditional approaches in the context of auxiliary function development. We conducted six experiments involving 122 participants (85 novices and 37 professionals) who used both traditional and agile methods to develop six auxiliary functions across three different domains. Our analysis of 244 implementations suggests the potential benefits of agile practices in auxiliary function development. Pair programming showed a tendency towards improved correctness, while test-first programming did not significantly extend the total development time, particularly among professionals. However, these findings should be interpreted cautiously as they do not conclusively establish that agile practices outperform traditional approaches universally. As indicated by our results, the potential benefits of agile practices may vary depending on factors such as the programmer's experience level and the nature of the functions being developed. Further research is needed to fully understand the contexts in which these practices can be most effectively applied and to address the potential limitations of our study. [ABSTRACT FROM AUTHOR]

5G NR is a wireless mobile communication system that supports ultra-high speed mobile communications, high reliability services, and large-scale Internet of Things. In a mobile communication environment, the Doppler effect, which is proportional to the speed of travel, causes channel changes over time, which can lead to communication performance degradation. In order to achieve optimal communication performance in a mobile communication environment, it is necessary to predict the Signal to Noise Ratio (SNR) between the base station and the terminal and select and transmit the most appropriate Modulation and Coding Scheme (MCS) accordingly. In this paper, we propose a method for selecting the MCS level of a single antenna based on Convolutional Neural Network (CNN) in 5G NR mobile communication systems. The proposed system assumes a time division duplex (TDD) scheme, measures the SNR at the time of reception, predicts the SNR at the time of future transmission using CNN based on the measured past channel information, and selects the MCS level based on the predicted SNR. Experimental results through computer simulation show that the proposed CNN-based MCS selection method has a lower probability of communication disconnection and higher transmission rate at all speeds compared to the existing average value method based on the average of SNR and the recent value method based on the most recently received SNR. In particular, the transmission speed of the proposed method is about 46% and 4.6% better than the existing average value method and recent value method, respectively, and can be utilized as a technology to increase the transmission speed in 5G mobile communication environment. [ABSTRACT FROM AUTHOR]

Access to and utilisation of antenatal care (ANC) is important for optimising health and nutrition during pregnancy. This study aimed to assess adherence to and factors associated with ANC and antenatal supplement use among Laotian women, and consider culturally appropriate strategies to increase micronutrient intakes. Mother-child (aged 21 d to

Test-driven development (TDD) is an agile practice of writing test code before production code, following three stages: red, green, and refactor. In the red stage, the test code is written; in the green stage, the minimum code necessary to make the test pass is implemented, and in the refactor stage, improvements are made to the code. This practice is widespread across the industry, and various studies have been conducted to understand its benefits and impacts on the software development process. Despite its popularity, TDD studies often focus on the technical aspects of the practice, such as the external/internal quality of the code, productivity, test smells, and code comprehension, rather than the context in which it is practiced. In this paper, we present a systematic literature review using Scopus, Web of Science, and Google Scholar that focuses on the TDD practice and the influences that lead to the introduction of test smells/anti-patterns in the test code. The findings suggest that organizational structure influences the testing strategy. Additionally, there is a tendency to use test smells and TDD anti-patterns interchangeably, and test smells negatively impact code comprehension. Furthermore, TDD styles and the relationship between TDD practice and the generation of test smells are frequently overlooked in the literature. [ABSTRACT FROM AUTHOR]

The usage of manufactured nanoparticles has grown over the past few decades in a variety of fields, including biomedicine, diagnostics, and environmental remediation, raising serious public concerns. Due to their numerous features, magnetic nanoparticles (MNPs) have attracted the most attention among these nanoparticles in the fields of medicine, pharmacology, drug delivery systems, molecular imaging, and biosensing. It is essential to note that whilst the systems' sizes are getting smaller due to the manufacturing of magnetic nanoparticles, the methods used to interpret their properties—bottom-up for the latter and top-down for the former—remain distinct. Here, we emphasise the necessity for a shared perspective whilst outlining the current state of the two domains and offering some predictions for potential future advancements. The review study discusses the use of MNPs in biomedicine, explains how they interact with living things, and assesses their toxicity. Also, clarify biocompatibility and add more information about the drug delivery system, such as targeted drug delivery. A thorough explanation of how MRI and the MNP work together is provided. Particular MNP applications were demonstrated using MRI, CT, and bioimaging. This would allow us to examine drug transport, tumour interaction, and toxicity. Additionally, difficulties with nanoparticles have been discussed, including stability, environmental toxicity, and safety measures. This review attempts to present a comprehensive summary of the state of current knowledge in magnetic nanoparticle research. [ABSTRACT FROM AUTHOR]

Currently in Ukraine, taking into account the development of the latest mobile Internet standards (3G/4G), it is possible to access the Internet even in remote places. There are no wired Internet due to the high cost of installation and maintenance. At the same time, a huge amount of equipment appeared on the market, which allows you to assemble systems for obtaining high-quality Internet over a wireless communication line. This refers to various types of antennas in the 900–2700MHz range, modems and routers with 3G/4G support. The locations of 3G/4G Internet base stations are in district centers predominantly. So, there is a situation that remote villages, settlements do not have the opportunity to get access to high-speed Internet. This especially harms the work of biological stations and rural medical clinics, which are spread over the territory of Ukraine and are often connected in a network. The purpose of the work is to describe briefly some practical results of our own development of providing high-quality mobile communication in some remote places of the territory of the state. To provide this service in remote areas of Ukraine, signal amplification is necessary. In addition, there is a problem with the propagation of radio waves over the rough terrains for the ultra short wave and microwave ranges. To solve this problem, it is proposed to use an external antenna with a high amplification factor, which will be installed at a height of at least 6 meters above the ground to reduce the impact of interference on the path of radio waves. [ABSTRACT FROM AUTHOR]

How to maximize the network service capability under the constraints of massive nodes and multi-domainresources is the core problem faced by TDD large-scale networking.The method of TDD large-scale networking under fully collaborative optimization architecture were innovatively proposed, which could maximize network service capabilities through inter layer and intra layer collaboration among wireless connection layer, signal processing layer and service control layer.Aiming at efficient use of wireless resources, the method of multi-domain conversion in wireless connection layer were put forward, including the principles and mechanism of space-time-frequency-code multi-domain conversion.The results of practical verification in 4G/5G existing network show that the proposed architecture and method of TDD large-scale networking can effectively control the interference while improving utilization of multi-domain resourcesto maximize network capacity.

This article presents fully integrated 39-GHz bidirectional up- and down-conversion mixers for 5G millimeter-wave (mmWave) applications. Fabricated in a 65-nm CMOS process with a 1.2-V supply voltage, the up- and down-conversion mixers consume 39 and 43 mW, respectively. For 5G time-division duplexing (TDD) operation, intermediate-frequency (IF)/local-oscillator (LO)/radio-frequency (RF) T/R switches are introduced. For better isolation and low insertion loss between the up- and down-conversion mixer, a series-shunt single-pole double-throw (SPDT) structure and an equivalent lumped λ/4 transmission line are proposed for IF and RF T/R switches, respectively. To realize compact area and wide bandwidth, a transformer-based matching network is adopted in this design. Targeting multi-channel phased array applications, the measurement result shows that the up-conversion mixer achieves a 2.5-dB peak conversion gain with 6.5 GHz 3-dB bandwidth. Including the insertion loss of the switch and IF signal routing, at the maximum gain of 36.5 GHz, the up-conversion mixer achieves an output 1-dB gain compression point (OP1dB) of 2.5 dBm. Furthermore, the down-conversion mixer achieves a 5-dB peak conversion gain with a 9.7-GHz 3-dB bandwidth.

Introduction: Type 2 diabetes mellitus (T2DM) is a non-communicable disease with a high prevalence in Indonesia. T2DM is caused by insulin resistance and relative insulin deficiency. One of the therapy for T2DM is insulin administration which is injected into the subcutaneous tissue. The absorption of insulin in the subcutaneous tissue is influenced by many factors, one of which is the thickness of subcutaneous fat. This study aimed to determine the correlation between the skinfold thickness of T2DM patients with the total daily dose of insulin needed every day. Methods: This was an observational analytic study using a cross-sectional design to analyze the correlation between subcutaneous fat thickness represented by skinfold thickness and the total daily dose of insulin of T2DM patients. Measurement of skinfold thickness was carried out on the triceps using a skinfold caliper. Data on the patient's total daily dose of insulin were obtained from medical records. Results: A total of 53 patients were included in this study. The patient's mean triceps skinfold thickness was 26.29±8.72 mm. The mean total daily dose of insulin was 40.96±18.01 IU. The results of the Spearman Rank correlation test showed a significant correlation between skinfold thickness on the triceps and the patient's total daily dose of insulin (p

How to maximize the network service capability under the constraints of massive nodes and multi-domainresources is the core problem faced by TDD large-scale networking. The method of TDD large-scale networking under fully collaborative optimization architecture were innovatively proposed, which could maximize network service capabilities through inter layer and intra layer collaboration among wireless connection layer, signal processing layer and service control layer. Aiming at efficient use of wireless resources, the method of multi-domain conversion in wireless connection layer were put forward, including the principles and mechanism of space-time-frequency-code multi-domain conversion. The results of practical verification in 4G/5G existing network show that the proposed architecture and method of TDD large-scale networking can effectively control the interference while improving utilization of multi-domain resources to maximize network capacity. [ABSTRACT FROM AUTHOR]

En la actualidad, se busca que el proceso de desarrollo de software sea más rápido y efectivo. Las principales causas que impiden cumplir con este objetivo son los errores en las especificaciones de requisitos y la ausencia de pruebas acordes al producto construido. Como consecuencia, se obtienen productos de software que no alcanzan la calidad esperada por los clientes. Por ello, es crítico que los equipos de desarrollo de software le den prioridad a la etapa de pruebas, así como a la definición correcta de los requisitos, para evitar crear un producto que pueda resultar en la pérdida de recursos y en la insatisfacción de los stakeholders. Como respuesta a esta problemática, en el ámbito de desarrollo de software, se han diseñado distintas prácticas basadas en pruebas para minimizar errores en el proceso de desarrollo, entre estas, se pueden mencionar: Test-Driven Development, Behaviour-Driven Development y Acceptance Test Driven Development. En este artículo, se aborda una revisión literaria de estas prácticas con el objetivo de determinar la importancia de cada una, en el proceso de desarrollo de software, mediante el análisis de sus características y diferencias.

Due to the ongoing trend of digitalization, the importance of software for today’s society is continuously increasing. Naturally, there is also a huge interest in improving its quality, which led to a highly active research community dedicated to this aim. Consequently, a plethora of propositions, tools, and methods emerged from the corresponding efforts. One of the approaches that have become highly prominent is the concept of test-driven development (TDD) that increases the quality of created software by restructuring the development process. However, such a big change to the followed procedures is usually also accompanied by major challenges that pose a risk for the achievement of the set targets. In order to find ways to overcome them, or at least to mitigate their impact, it is necessary to identify them and to subsequently raise awareness. Furthermore, since the effect of TDD on productivity and quality is already extensively researched, this work focuses only on issues besides these aspects. For this purpose, a literature review is presented that focuses on the challenges of TDD. In doing so, challenges that can be attributed to the three categories of people, software, and process are identified and potential avenues for future research are discussed.

Test-driven development (TDD) is an agile practice of writing test code before production code, following three stages: red, green, and refactor. In the red stage, the test code is written; in the green stage, the minimum code necessary to make the test pass is implemented, and in the refactor stage, improvements are made to the code. This practice is widespread across the industry, and various studies have been conducted to understand its benefits and impacts on the software development process. Despite its popularity, TDD studies often focus on the technical aspects of the practice, such as the external/internal quality of the code, productivity, test smells, and code comprehension, rather than the context in which it is practiced. In this paper, we present a systematic literature review using Scopus, Web of Science, and Google Scholar that focuses on the TDD practice and the influences that lead to the introduction of test smells/anti-patterns in the test code. The findings suggest that organizational structure influences the testing strategy. Additionally, there is a tendency to use test smells and TDD anti-patterns interchangeably, and test smells negatively impact code comprehension. Furthermore, TDD styles and the relationship between TDD practice and the generation of test smells are frequently overlooked in the literature.

In this study, we identified the relationship between Ground Surface Temperature (GST) with the geography and environmental factors in the Terkh River Valley, Mongolia, and explored the possibility of using satellite data to determine active layer thickness and seasonally frozen ground changes. We obtained data from three boreholes for the permafrost monitoring, and ten GST measuring instruments that we installed in the valley. According to the results, the active layer thickness at the three boreholes varied between 2.8 and 6.22 m. In the Terkh Ar borehole, the active layer thickness increased by 5 cm per year, while the seasonally frozen ground depth in the Terkh Uvur borehole decreased by 12 cm during the study period. When comparing mean GST with geographic factors such as elevation, slope, and aspect, the correlation was weak (R² = 0.026-0.23). However, when comparing mean GST in the summer season with indices such as MSAVI, MNDWI, and NDMI, the correlation was high (R2 = 0.37-0.91). The highest value of the thawing degree days (TDD) was 2708°C and observed at T-10, while the lowest value of the TDD was 1174°C and observed at T-1. The minimum value of freezing degree days (FDD) was -3020°C and observed at the T-n point, while the maximum value of FDD was -1553°C and observed at the T-10 point. The N-factor derived from the FDD and TDD values revealed a high correlation with the MSAVI index (R² = 0.77). It is indicated that the MSAVI index can be one of the factors modeling the active layer thickness. [ABSTRACT FROM AUTHOR]

In this study, an in vitro experimental system is developed for fifth-generation (5G) 3.5 GHz exposures. A radial transmission line (RTL) housed in an incubator can support the single-mode propagation at a 3.5 GHz band. A conical antenna is also placed at the center of an RTL to ensure field symmetries. A 5G signal generator along with a customized power amplifier can create 5G new radio time division duplex (TDD) waveforms. Additionally, a feedback scheme implemented by employing a directional coupler and power meter allows power control to ensure a steady output power. The system is evaluated based on temperature measurements using the initial temperature slope and nonlinear curve fitting to determine the specific absorption rate (SAR) values. Comparing SARs obtained from a “worst-case” signal of a maximum power condition with the values obtained from a “TDD” signal of an actual 5G TDD transmission gives the initial slope ratio of 0.741, which is very similar to the theoretical duty cycle of 0.743. It is also shown that the average output power, water temperature, incubator air temperature, and CO2 density are adequately controlled for appropriate in vitro experiments.

With new services emerging in fifth generation (5G)-advanced, the evolution in duplex modes plays an important role to meet more stringent requirements for both downlink (DL) and uplink (UL) transmissions. In this paper, sub-band full duplex (SBFD) at base station (BS) is studied as an attainable evolution of the traditional time division duplex (TDD). Both user equipment (UE) transparent SBFD and UE perceptive SBFD are proposed and studied to serve different types of UEs. To tackle the interference introduced by SBFD, a model including both BS self-interference and cross-link interference (CLI) is presented as a first step, and new interference management schemes are proposed. Three approaches to mitigate BS self-interference, namely the passive suppression, analog interference cancellation and digital interference cancellation are analyzed. A new framework for CLI management is illustrated along with enhancements for interference identification, spatial domain interference coordination and power domain adjustment. To validate the feasibility and performance of the proposed SBFD methods under indoor and dense urban scenarios, system-level simulations (SLSs) are carried out and a proof-of-concept (PoC) is developed for the purpose of obtaining experimental results.

Robust, fault tolerant, and available systems are fundamental for the adoption of Internet of Things (IoT) in critical domains, such as finance, health, and safety. The IoT infrastructure is often used to collect a large amount of data to meet the business demands of Smart Cities, Industry 4.0, and Smart Home, but there is a opportunity to use these data to intrinsically monitor an IoT system in an autonomous way. A Test Driven Development (TDD) approach for automatic module assessment for ESP32 and ESP8266 IoT development devices based on unsupervised Machine Learning (ML) is proposed to monitor IoT device status. A framework consisting of business drivers, non-functional requirements, engineering view, dynamic system evaluation, and recommendations phases is proposed to be used with the TDD development tool. The proposal is evaluated in academic and smart home study cases with 25 devices, consisting of 15 different firmware versions collected in one week, with a total of over 550,000 IoT status readings. The K-Means algorithm was applied to free memory available, internal temperature, and Wi-Fi level metrics to automatically monitor the IoT devices under development to identify device constraints violation and provide insights for monitoring frequency configuration of different firmware versions. To the best of the authors' knowledge, it is the first TDD approach for IoT module automatic assessment which uses machine learning based on the real testbed data. The IoT status monitoring and the Python scripts for model training and inference with K-Means algorithm are available under a Creative Commons license. [ABSTRACT FROM AUTHOR]

Future wireless networks will require advance physical-layer techniques to meet the requirements of Internet of Everything (IoE) applications and massive communication systems. To this end, a massive MIMO (m-MIMO) system is to date considered one of the key technologies for future wireless networks. This is due to the capability of m-MIMO to bring a significant improvement in the spectral efficiency and energy efficiency. However, designing an efficient downlink (DL) training sequence for fast channel state information (CSI) estimation, i.e., with limited coherence time, in a frequency division duplex (FDD) m-MIMO system when users exhibit different correlation patterns, i.e., span distinct channel covariance matrices, is to date very challenging. Although advanced iterative algorithms have been developed to address this challenge, they exhibit slow convergence speed and thus deliver high latency and computational complexity. To overcome this challenge, we propose a computationally efficient conjugate gradient-descent (CGD) algorithm based on the Riemannian manifold in order to optimize the DL training sequence at base station (BS), while improving the convergence rate to provide a fast CSI estimation for an FDD m-MIMO system. To this end, the sum rate and the computational complexity performances of the proposed training solution are compared with the state-of-the-art iterative algorithms. The results show that the proposed training solution maximizes the achievable sum rate performance, while delivering a lower overall computational complexity owing to a faster convergence rate in comparison to the state-of-the-art iterative algorithms. [ABSTRACT FROM AUTHOR]

The 5G non-public network deployments for industrial applications are becoming highly interesting for industries and enterprises owing to dependable wireless performance characteristics. With an increasing trend of network deployments in local licensed and/or shared spectrum, coexistence issues naturally arise. In this article, we present our detailed empirical results on the performance impact of a 5G NR indoor non-public network from a 5G NR outdoor network operating in the same mid-band spectrum. We present experimental results on the uplink and downlink performance impact of a non-public indoor network deployed on an industrial shopfloor. Our results quantify the impact on the uplink and downlink performance characteristics based on realistic traffic loads in a non-public indoor network when using synchronized and unsynchronized Time Division Duplex (TDD) patterns, different UE deployment locations and interference levels. We also present results on mitigating interference effects through robust link adaptation techniques. We believe that this is the first article, which reports quantified 5G NR cochannel coexistence results based on a detailed and systematic study, and provides signficant insights on the cochannel coexistence behavior in realistic deployment scenarios of an industrial shopfloor. [ABSTRACT FROM AUTHOR]

Objective: Continuous subcutaneous insulin infusion (CSII) in youths with type 1 diabetes (T1D) is often associated with lower HbA1c, lower total daily insulin dose (TDD), and lower body mass index (BMI) compared with multiple daily injections (MDI). Individual responses to CSII are diverse. The aim was to identify unique three‐variate patterns of HbA1c, BMI standard deviation score (SDS), and TDD after switching to CSII. Methods: Five thousand one hundred and thirty‐three youths (≤20 years; 48% boys; median age at pump start 12.5 years) with T1D duration ≥3 years at CSII initiation were selected from the multicenter DPV registry. We applied group‐based multitrajectory modeling to identify groups of individuals following similar trajectories. Measurements were aggregated quarterly during a 3‐year follow‐up period. Trajectory variables were changes of HbA1c, BMI‐SDS, and TDD from baseline (delta = quarterly aggregated values at each time point [i] minus the respective baseline value). Results: Four groups of diverging Delta‐HbA1c, Delta‐BMI‐SDS, and Delta‐TDD patterns were identified. All showed improvements in HbA1c during the first 3 months. Group 1 (12%) was characterized by modest HbA1c increase thereafter, TDD reduction, and stable BMI‐SDS. In Group 2 (39%), increasing HbA1c, decreasing BMI‐SDS, and stable TDD were found. By contrast, sustainably improved HbA1c, increasing BMI‐SDS, and stable TDD were observed in Group 3 (32%). Group 4 (17%) was characterized by increasing levels for HbA1c, BMI‐SDS, and TDD. Between‐group differences in baseline HbA1c, BMI‐SDS, TDD as well as in sex ratio, age at diabetes onset and at pump start were observed. Conclusions: Definite trajectories of glycemic control, BMI, and TDD over 3 years after CSII initiation were identified in youths with T1D allowing a more personalized treatment recommendation. [ABSTRACT FROM AUTHOR]

Bidirectional electric vehicle supply equipment and charging stations (EVSE) offer new business models and can provide services to the electrical grid. The smart grid lab in Vienna gives unique testing possibilities of future smart grids, as different type of electrical equipment can be operated at a reconstructed, well-known distribution grid. In this work the harmonic and supraharmonic emissions of a bidirectional EVSE are measured according to IEC61000-4-7 and IEC61000-4-30 Ed3 standard as well as the high-frequency grid impedance. In addition, the efficiency and the power factor are determined at various operating points. Although THDi at nominal power (10 kW) is very low and the efficiency and power factor is very high, at low power levels the opposite situation arise. Supraharmonic emissions remain stable independent of the charging/discharging power, and both wideband and narrowband emissions occur. The additional capacitance when connecting the EVSE impacts the high-frequency grid impedance substantially and generates resonance points. [ABSTRACT FROM AUTHOR]

Massive multiple-input multiple-output (MIMO) employs a large antenna array and is used as a key technology in 5G communication standards. In this work, time-division duplex (TDD) is used for uplink (UL) and downlink (DL) channels as the same bandwidth can be utilized for bidirectional data transfer. This paper proposes a computationally efficient adaptive algorithm based channel estimation model. These models are applicable to multiuser MIMO (MU-MIMO) systems, which are comprised of a large number of channel coefficients. Channel state information (CSI) is acquired from estimated channel coefficients of the UL channel, and CSI of DL is obtained through channel reciprocity. The dynamic characteristics of MIMO channels are generally sparse in nature, and the degree of sparseness varies over time. Convex combination-based modeling with the introduction of l0 norm penalty to Least mean squares (LMS) algorithm develops an efficient and stable sparse channel estimation model, which is the most significant contribution of the paper. The research work presented in the paper has simultaneously focused on channel estimation using the convex combination of momentum-fractional LMS approach and equalization for massive MIMO channels. The simulation result exhibits that the proposed method outperforms the existing conventional compressed sensing (CS) based channel estimation. The UL and DL performance of the system was investigated in terms of bit error rate (BER), mean square error (MSE), and channel capacity calculated from estimated CSI. [ABSTRACT FROM AUTHOR]

Technology advances every day because the business world should not be left behind in it, so there is the adoption of new ways of doing business. This is how ICT (Information and Communication Technologies) plays a key role in these new companies converting traditional processes such as bringing your customers through a web converting to e-Commerce, to a digital process. Due to the rise of ICT has been the implementation of electronic billing systems, this type of systems come to stay; improvements are given based on an already predetermined structure, mapping in a better way the taxes and operations of taxpayers. Then, this type of business implies having well-trained IT and accounting staff that allows the online sending of the CPE (electronic receipts). Therefore, this project seeks to improve an internal process in the development phase of the OSE BIZ LINKS that grants validity to electronic receipts, for we will use tools that can be reusable over time, such as Data-Driven Testing, which is a testing technique that has as its pillar two types of data: real data (functional test results) and expected data (results that should have each functional test case), making a comparison of both proceedings to report according to each data compared in this process. [ABSTRACT FROM AUTHOR]

Test-driven development (TDD) is an agile development technology that involves the running of many test cases. The software is likely to be more robust when more test cases are executed in a certain time. For this, it is important to find the combination of number of threads and test cases which can lead to the lowest average running time of a single test case aiming at different computers. It can improve the performance of TDD. Therefore, this paper proposed a method for this problem. First, it tests the three-dimensional raw data in computers with different cores. Second, these data are changed into two-dimensional data after dimensionality reduction. This facilitates the generation of fitting functions. Also, the fitting function of new data waiting for prediction is generated after dimensionality reduction. At last, similarity calculations between the fitting functions of raw and new data are carried out by using Euclidean distance similarity algorithms. Experimental results show that data based on dual-core computer have higher similarities with four new data, such as 81.25%, 100%, 81.25%, and 100%. Thus, the data of dual-core computer have higher reference credibility in predicting the average running time of a single test case of the new data for different computers. In summary, the performance of TDD can be improved after applying the proposed method. [ABSTRACT FROM AUTHOR]

Multiband operation in millimeter wave (mmWave) will obtain lots of performance gain by offering larger bandwidth. However, the prerequisite is the acquisition of accurate channel state information (CSI), which is a knotty task with hybrid analog/digital architecture. This study devotes to efficiently reconstruct and track the time drifting multiband channel to keep CSI precise in time division duplex (TDD) mmWave multiple-input-multiple-output system with hybrid analog/digital architecture. Utilizing spatial reciprocity, an efficient multiband channel reconstruction scheme is introduced, which elaborately estimates the central sub-band channel and then reconstructs side sub-band channels from the central one. To this end, a beam training-based Newtonized orthogonal matching pursuit (BT-NOMP) algorithm is proposed to estimate the central sub-band channel. With the help of frequency-independent parameters extracted from BT-NOMP, side sub-bands channel can be well reconstructed with additional low-complexity path gains estimation process. Furthermore, to avoid frequent channel reconstruction in a slightly drifting channel meanwhile keep the CSI accurate, a rotated beam-based channel tracking algorithm is developed using historical observations of channel parameters. Numerical results prove the efficiency of the proposed multiband channel reconstruction scheme and the accuracy of the channel tracking algorithm. [ABSTRACT FROM AUTHOR]

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Massive Multiple Input Multiple Output (MIMO) is an essential component for future wireless cellular networks. One of its biggest advantages is to use the 5G spectrum more intelligently by extending both coverage (via high gain adaptive beamforming) and capacity (via high order spatial multiplexing). In this paper, we evaluate the performance of Time-division duplex (TDD)-based massive MIMO deployment scenario in one of the commercial sites in Turkey. Our experimental results reveal three major contributions: (i) TDD-based massive MIMO in 10 Mhz reveals up to 212% and 50% higher cell throughput compared to Frequency-division duplex (FDD)-based MIMO deployments with 10 Mhz and 20 Mhz respectively. The Downlink (DL) throughput is also observed to be better in mid/far points. (ii) Together with the usage of TDD-based massive MIMO inside the same commercial site, median values of total cell traffic, Uplink (UL) Spectral Efficiency (SE) and DL schedule Transmission Time Interval (TTI) duty cycle have improved 38%, 9% and 14.5% compared to FDD-based MIMO scenario respectively. (iii) Finally, we address some of the challenges of the massive MIMO deployments and the possible trade-offs that can be observed in terms of Radio Resource Control (RRC)-connected User Equipments (UEs), cell throughput, available Sounding Reference Signal (SRS) resources and pairing opportunities provided by massive MIMO.

Abstract Energy-saving for the LTE-A network with relay nodes in TDD mode is addressed in this paper, and integrated sleep scheduling schemes for relay nodes and user devices under a base station are designed. The authors’ two previously proposed ideas, namely, Load-Based Power Saving (LBPS) and Virtual Time, are adopted in the design, and two strategies, namely, top-down and bottom-up each with three LBPS schemes are proposed. In the top-down strategy, the load as well as the channel quality on the backhaul link is first considered to determine the sleep pattern for all relay nodes, and then the sleep schedule for UEs under each relay node is determined accordingly. On the contrary, the load and the channel quality on the access links are first considered and then integrated into the sleep schedule on the backhaul link. Two associated mechanisms for the proposed LBPS schemes to operate in the virtual time domain are also proposed in the paper, i.e., calculation of the virtual subframe capacity and the mapping mechanisms from the virtual time to the actual time. The benefit of the proposed schemes in power saving over the standard-based scheme is demonstrated by the simulation study, and the bottom-up scheme of BU-Split outperforms the other schemes under equally distributed input load as well as the hotspot scenario. Discussion on the tradeoff of the processing overhead and the performance for the proposed schemes is presented in the paper.