Abstract This paper presents an error performance analysis and a model of a narrow-band power line carrier (PLC) system for smart metering. Our work is founded on complex analysis based on the probability theory using limited, long-term measurement data of a rural 400 V distribution grid during operation. To obtain confident results, the analysis and modeling of the error performance were done in two steps. In the first step, the Neyman contagious distribution, originally derived in the fields of entomology and bacteriology, was applied to describe the probability distribution of errors in messages in consideration of the impulsive noise in the PLC channel and the influence of forward error correction techniques. In the second step, assuming the bit error rate (BER) was a random variable, where errors are randomly distributed in the sample rather than clustered into messages, the confidence interval of the true BER was calculated for different SNR values. The results served as a foundation for the error performance model proposed in this paper. The presented work is crucial for the research of upper layer communication protocols performance incorporating advanced phenomena at the physical layer.

Abstract A mathematical model which can describe flow and phase change of a number of phases at high temperatures is presented. It combines an interface capturing multiphase model, the P–1 radiation model, and a melting/solidification model. The resulting equations are solved by employing the finite volume discretization, a segregated solution procedure and the SIMPLE algorithm. The melting/solidification model is a finite rate model which in the limiting case behaves like a thermodynamic equilibrium model and it can also be used in situations where the phase change occurs within a range of temperatures as well as for problems where the phase change occurs at a constant temperature. The method is verified on a number of problems. The results obtained show a good agreement with exact solutions or results which can be found in literature.

This paper analyses the impact of the human body on antenna radiation characteristics, with a focus on the polarization aspect. The effect of the body tissues on a wrist-worn ultra-wideband double loop antenna radiation characteristics is investigated at 3, 4 and 5 GHz, based on numerical full-wave simulations complemented with a voxel model of a hand. Results show a strong influence of the body on the gain and polarization characteristics; the radiation in the direction towards the body is suppressed by 20 dB or more, and the antenna polarization changes from a linear to an elliptical one. By simulating an off-body communications scenario with the user walking at a fixed distance from the off-body antenna, up to 6.5 dB lower received power is obtained by using the wearable antenna radiation pattern simulated with the hand phantom, compared to the case when the antenna in free space.

This paper presents an empirical validation of a polarized channel model for off-body communications with dynamic users, based on wideband indoor measurements at 5.8 GHz with a 500 MHz bandwidth. The model is based on geometrical optics, and takes the signal depolarization and influence of user dynamics into account. By considering a scenario with the user walking towards an access point with co-located vertical and horizontal dipole antennas, the simulated receiver (Rx) power is compared against measurements for wearable antenna placements on the chest, wrist and lower leg. The obtained root mean square error is found to be within 2.8 dB for the vertical off-body antenna polarization, and within 3.2 dB for the horizontal one. Fairly matching Rx power values are obtained even when only free space propagation is considered in the simulator, with the error being below 3.4 dB in most cases.

Despite the rapid improvements in the field of microgrid protection, it continues to be one of the most important challenges faced by the distribution system operators. With the introduction of this new operation concept, the existing protection devices are not able to successfully identify, classify and localize different types of faults that occur in the microgrids due to their dynamic behaviour, especially in the islanded mode of operation. This paper presents a methodology that provides the station protection functionalities that include detection and classification of faults, isolation of the faulty feeder and fault location estimation. The proposed method is based on discrete wavelet transform and artificial neural networks. The test system based on the real data, completely developed in MATLAB Simulink, is used to demonstrate the accuracy of all functionalities of the station protection algorithm that can be easily applied in microgrids. The presented results demonstrated the method accuracy and showed that it can be used as an upgrade of the existing protection equipment for the future implementation of the advanced microgrid station protection system.

Previous transcriptome-wide association studies (TWAS) have identified breast cancer risk genes by integrating data from expression quantitative loci and genome-wide association studies (GWAS), but analyses of breast cancer subtype-specific associations have been limited. In this study, we conducted a TWAS using gene expression data from GTEx and summary statistics from the hitherto largest GWAS meta-analysis conducted for breast cancer overall, and by estrogen receptor subtypes (ER+ and ER−). We further compared associations with ER+ and ER− subtypes, using a case-only TWAS approach. We also conducted multigene conditional analyses in regions with multiple TWAS associations. Two genes, STXBP4 and HIST2H2BA, were specifically associated with ER+ but not with ER− breast cancer. We further identified 30 TWAS-significant genes associated with overall breast cancer risk, including four that were not identified in previous studies. Conditional analyses identified single independent breast-cancer gene in three of six regions harboring multiple TWAS-significant genes. Our study provides new information on breast cancer genetics and biology, particularly about genomic differences between ER+ and ER− breast cancer.

S U M M A R Y Inversions of planetary gravity are aimed at constraining the mass distribution within a planet or moon. In many cases, constraints on the interior structure of the planet, such as the depth of density anomalies, must be assumed a priori, to reduce the non-uniqueness inherent in gravity inversions. Here, we propose an alternative approach that embraces the non-uniqueness of gravity inversions and provides a more complete view of related uncertainties. We developed a Transdimensional Hierarchical Bayesian (THB) inversion algorithm that provides an ensemble of mass distribution models compatible with the gravitational field of the body. Using this ensemble of models instead of only one, it is possible to quantify the range of interior parameters that produce a good fit to the gravity acceleration data. To represent the interior structure of the planet or moon, we parametrize mass excess or deficits with point masses. We test this method with synthetic data and, in each test, the algorithm is able to find models that fit the gravity data of the body very well. Three of the target or test models used contain only point mass anomalies. When all the point mass anomalies in the target model produce gravity anomalies of similar magnitudes and the signals from each anomaly are well separated, the algorithm recovers the correct location, number and magnitude of the point mass anomalies. When the gravity acceleration data of a model is produced mostly by a subset of the point mass anomalies in the target model, the algorithm only recovers the dominant anomalies. The fourth target model is composed of spherical caps representing lunar mass concentration (mascons) under major impact basins. The algorithm finds the correct location of the centre of the mascons but fails to find their correct outline or shape. Although the inversion results appear less sharp than the ones obtained by classical inversion methods, our THB algorithm provides an objective way to analyse the interior of planetary bodies that includes epistemic uncertainty.

Abstract Understanding present-day mantle heterogeneity is key to understanding the geochemical evolution of our planet. The Samoan islands are the type locality for the Enriched Mantle (II) reservoir that is thought to be produced from the subduction and recycling of marine sediment from upper continental crust. In addition to hosting extreme radiogenic isotope compositions from the EM II reservoir, Samoa also exhibits contributions from other mantle reservoirs in a dilute form including the EM (I) (recycled continental material), HIMU (recycled oceanic crust), and DMM (depleted upper mantle) mantle reservoirs. The plume system feeding the Samoan islands sits above a seismically imaged Large Low Shear Velocity Province (LLSVP) and an Ultra-Low Velocity Zone (ULVZ) that is thought to contribute, in addition to recycled components, the recently discovered early-formed (primordial) components with negative μ 182 W and high 3He/4He. Recent work measuring sulfur isotopes in ocean island basalts has established that recycled oceanic and continental crust host unique S-isotope compositions that can be identified at various hotspot localities. Here we document previously unknown relationships between Δ 33 S and radiogenic tungsten, helium and lead isotopes from 7 Samoan basalts (from the islands of Ofu, Vailulu'u and Malumalu) that suggest mixing between several endmembers. One, a HIMU influence that has slight positive Δ 33 S and positive δ 34 S; another, related to EM II that has near zero Δ 33 S and positive δ 34 S; a third, which is primordial with negative μ 182 W, high 3He/4He, that has Δ 33 S = 0 and negative δ 34 S. From this, we conclude that the indistinguishable Δ 33 S of the primordial endmember from that of the convective mantle indicates that sulfur isotopes were homogenized early in Earth's history. The Vailulu'u sample with HIMU characteristics, carries a small but resolvable Δ 33 S that allows, but does not require mass-independent Archean Δ 33 S to shift the Δ 33 S. The observed correlations involving Δ 33 S support arguments linking Pb, He, and W geochemistry to a deep mantle process and places constraints on questions related to the sources of mantle geochemical heterogeneity.

The paper presents an online web-oriented system named SOLARS, which is aimed at calculating the feasibility of building the photovoltaic (PV) systems. SOLARS currently enables potential investors to calculate the technical and financial feasibility of building the PV systems in the Republic of Srpska (Bosnia and Herzegovina). Very intuitive GUI design enables investors to obtain feasibility calculations in three simple steps: (i) selection of a geographical location, (ii) specification of technical parameters, and (iii) specification of financial parameters. A usage scenario is illustrated by a real feasibility calculation example.

Postural orthostatic tachycardia syndrome (POTS) is a chronic, debilitating condition characterized by heterogeneous symptoms, such as lightheadedness, palpitations, pre-syncope, syncope, and weakness or heaviness, especially of the legs. It is frequently associated with hypermobile joints or conditions such as chronic fatigue syndrome, chronic abdominal pain, migraine headache, and diabetes mellitus. Described is a case of POTS, which though it is not rare, is rarely diagnosed. It can be diagnosed quickly with simple methods.

Aim: A large number of medications are prescribed in pediatric clinics and this leads to the development of drug–drug interactions (DDI) that may complicate the course of the disease. The aim of the study was to identify the prevalence of potential drug–drug interactions, to categorize main drug classes involved in severe drug–drug interactions and to highlight clinically relevant DDIs in a pediatric population. Material and Methods: A total of 1500 prescriptions during the 12-month study period were retrospectively reviewed; 510 prescriptions that comprised two or more drugs were included in study. The presence of potential drug–drug interactions was identified by using the Lexi-Interact database and categorized according to severity A (unknown), B (minor), C (moderate), D (major), and X (contraindicated). Results: There were 1498 drugs in 510 prescriptions; 253 of these (49.6%) included 2 drugs, 228 (44.7%) included 3–4 drugs, and 29 (5.6%) included ≥5 drugs. A total of 634 (42%) potential drug–drug interactions were idenfied. Among those, 271 (42.7%) were categorized as A, 284 (44.8%) as B, 53 (8.4%) as C, and 26 (4.1%) as D. There was no potential risk for X interaction. Anti-infectives (36%) were the most commonly prescribed drug classes involved in C and/or D categories. Clarithromycin was the most commonly interacting agent that interfered with budesonide. Conclusion: It is noteworthy that a significant number of drugs causing potential drug–drug interactions are prescribed together in pediatric clinics. Increasing the awareness of physicians on this issue will prevent potential complications and ensure patient safety.