Trends in Fathers' Contribution to Housework and Childcare under Different Welfare Policy Regimes

This article brings up to date welfare regime differences in the time fathers spend on childcare and core housework, using Multinational Time Use Study data (1971–2010) from fifteen countries. Although Nordic fathers continue to set the bar, the results provide some support for the idea of a catch-up in core housework among Southern regime fathers. The results also suggest an increasing polarization in Liberal countries, whereby fathers who were meaningfully involved in family life were increasingly likely to spend more time doing core housework and, particularly, childcare. Fathers living in Corporatist countries have been least responsive to change

Validity and limitations of the median-line integral equation technique in the scattering by material strips of sub-wavellength thickness

Cataloged from PDF version of article.Considered is the 2-D scattering of a plane wave by a thin flat material strip. The data obtained by using the empirical method of generalized boundary conditions and singular integral equations on the strip median line are compared with the results of solving the Muller boundary integral equation that takes full account of strip thickness. Discretization of integral equations in both cases is performed using the Nystrom methods that lead to convergent algorithms. Numerical results cover E and H polarizations and two types of thin strips: conventional dielectric and metal in the optical range. The validity and limitations of approximate model are established and discussed

Computer aided frequency planning for the radio and tv broadcasts

Cataloged from PDF version of article.The frequency planning of the VHF and UHF broadcasts in Turkey is described. This planning is done with the aid of computer databases and digital terrain map. The frequency offset is applied whenever applicable to increase the channel capacity. The offset assignment is done through Simulated Annealing algorithm. The international rules and regulations concerning Turkey are also considered

Effect of dentin desensitizing procedures on methyl methacrylate diffusion through dentin

Background: Acrylic and bisacryl resins are widely used both during the temporization phase as well as for provisional restorations and the effect of external agents on dentin sensitivity can be reduced by the obliteration of the tubules.Objective: The purpose of this study was to evaluate diffusion of methyl methacrylate monomer through dentin by high performance liquid  chromatography (HPLC) after three different desensitizing procedures during the fabrication of two different provisional crown materials.Materials and Methods: Forty extracted restoration and caries free human premolar teeth were used in this study. Thermoplastic vacuum formed material was used as a matrix to fabricate provisional restorations for each tooth before crown preparation. Teeth were prepared for a metal supported ceramic crown with 1 mm shoulder margins and then crown parts were  separated from cementoenamel junction with a carborundum disk  perpendicular to the long axis of the teeth. To the cementoenamel junction of each tooth a polypropylene chamber was attached that contains 1.5 cm3of deionized distilled water. Prepared teeth were divided into four groups (n = 10) including control, desensitizing agent (DA) application,  neodymium.doped yttrium aluminum garnet (Nd: YAG) laser irradiation (LI), and LI after DA application groups. After application of DA (except control) each group were divided into two subgroups for fabrication of provisional restorations (n = 5). Two autopolymerizing provisional materials (Imident (Imicryl) and Systemp C and B (Ivoclar, vivadent)) were used to fabricate provisional restorations using the strips. Water elutes were analyzed by HPLC at 10 min and 24 h.Results: The monomer diffusion values varied statistically according to desensitizing procedures, provisional resin systems, and the time periods. Monomer diffusion through dentin surfaces desensitized with Nd: YAG LI after DA application was the lowest.Conclusions: Nd: YAG LI in association with DA application is an effective combination to eliminate monomer diffusion through dentin to pulpal chamber.Key words: Dentin hypersensitivity, dentin permeability, laser, monomer diffusion, provisional crow

RAFT-based polystyrene and polyacrylate melts under thermal and mechanical stress

Although controlled/living radical polymerization processes have significantly facilitated the synthesis of well-defined low polydispersity polymers with specific functionalities, a detailed and systematic knowledge of the thermal stability of the products-highly important for most industrial processes-is not available. Linear polystyrene (PS) carrying a trithiocarbonate mid-chain functionality (thus emulating the structure of the Z-group approach via reversible addition-fragmentation chain transfer (RAFT) based macromolecular architectures) with various chain lengths (20 kDa ≤ Mn,SEC ≤ 150 kDa, 1.27 ≤ Crossed D sign = Mw/Mn ≤ 1.72) and chain-end functionality were synthesized via RAFT polymerization. The thermal stability behavior of the polymers was studied at temperatures ranging from 100 to 200 C for up to 504 h (3 weeks). The thermally treated polymers were analyzed via size exclusion chromatography (SEC) to obtain the dependence of the polymer molecular weight distribution on time at a specific temperature under air or inert atmospheres. Cleavage rate coefficients of the mid-chain functional polymers in inert atmosphere were deduced as a function of temperature, resulting in activation parameters for two disparate Mn starting materials (Ea = 115 ± 4 kJ·mol-1, A = 0.85 × 109 ± 1 × 109 s-1, M n,SEC = 21 kDa and Ea = 116 ± 4 kJ·mol -1, A = 6.24 × 109 ± 1 × 109 s-1, Mn,SEC = 102 kDa). Interestingly, the degradation proceeds significantly faster with increasing chain length, an observation possibly associated with entropic effects. The degradation mechanism was explored in detail via SEC-ESI-MS for acrylate based polymers and theoretical calculations suggesting a Chugaev-type cleavage process. Processing of the RAFT polymers via small scale extrusion as well as a rheological assessment at variable temperatures allowed a correlation of the processing conditions with the thermal degradation properties of the polystyrenes and polyacrylates in the melt. © 2013 American Chemical Society.C.B.-K and M.W. gratefully acknowledge financial support from the German Research Council (DFG). M.L.C gratefully acknowledges generous allocations of supercomputing time from the Australian National Computing Facility, financial support from the Australian Research Council (ARC) Centre of Excellence for Free-radical Chemistry and Biotechnology and an ARC Future Fellowship. C.B.-K. acknowledges additional funding from the Karlsruhe Institute of Technology (KIT) in the context of the Helmholtz programs

Extraction of primary and secondary frequency control from active power generation data of power plants

Frequency control is a vital component of a secure and robust power grid and it ought to be closely monitored. Frequency control consists of two main components; primary and secondary control and their contributions are usually aggregated in the active power generation data of a plant, which is acquired via Supervisory Control And Data Acquisition. In many cases, such as in Turkey, they are demanded to be evaluated separately due to different impacts on power system or different financial policies. However, this is not usually a straightforward process since primary and secondary response cannot be obtained distinctly. In this work, Extraction of Primary and Secondary Control (EPSCon) algorithm is introduced to extract primary and secondary response over active power generation data. Based on time and frequency domain characteristics of primary and secondary response, EPSCon is developed on a Expectation-Maximization type recursive scheme employing Generalized Cross Correlation and ℓ1 Trend Filtering techniques. Favorably, EPSCon uses a simple plant model built upon basic governor and plant load controller technical characteristics as an initial estimate of primary and secondary response. © 2015 Elsevier Ltd. All rights reserved

End-to-End V2X Latency Modeling and Analysis in 5G Networks

networks provide higher flexibility and improved performance compared to previous cellular technologies. This has raised expectations on the possibility to support advanced Vehicle to Everything (V2X) services using the cellular network via Vehicle-to-Network (V2N) and Vehicle-to-Network-to-Vehicle (V2N2V) connections. The possibility to support critical V2X services using 5G V2N2V or V2N connections depends on their end-to-end (E2E) latency. The E2E latency of V2N2V or V2N connections depends on the particular 5G network deployment, dimensioning and configuration, in addition to the network load. To date, few studies have analyzed the capabilities of V2N2V or V2N connections to support critical V2X services, and most of them focus on the 5G radio access network or consider dedicated 5G pilot deployments under controlled conditions. This paper progresses the state-of-the-art by introducing a novel E2E latency model to quantify the latency of 5G V2N and V2N2V communications. The model includes the latency introduced at the radio, transport, core, Internet, peering points and application server (AS) when vehicles are supported by a single mobile network operator (MNO) and when they are supported by multiple MNOs. The model can quantify the latency experienced when the V2X AS is deployed from the edge of the network (using MEC platforms) to the cloud. Using this model, this study estimates the E2E latency of 5G V2N2V connections for a large variety of possible 5G network deployments and configurations. The analysis helps identify which 5G network deployments and configurations are more suitable to meet V2X latency requirements. To this aim, we consider as case study the cooperative lane change service. The conducted analysis highlights the challenge for centralized network deployments that locate the V2X AS at the cloud to meet the latency requirements of advanced V2X services. Locating the V2X AS closer to the cell edge reduces the latency. However, it requires a higher number of ASs and also a careful dimensioning of the network and its configuration to ensure sufficient network and AS resources are dedicated to serve the V2X traffic

An electromagnetic sensing system incorporating multiple probes and single antenna for wireless structural health monitoring

In this study, a wireless and passive displacement/strain sensing system is proposed for structural health monitoring (SHM). The wireless and passive interrogation of the sensing unit [a variant of a nested split-ring resonator (NSRR)] is achieved through the near-field interaction and electromagnetic coupling between the single antenna in the system and the multiple sensors called the NSRR probes. It is demonstrated that the system can acquire data from more than one NSRR probe simultaneously in a real-life scenario, where the probes are confined within concrete inside a beam, while the antenna monitors them from outside. © 2017 Euraap

A wireless passive sensing system for displacement/strain measurement in reinforced concrete members

In this study, we show a wireless passive sensing system embedded in a reinforced concrete member successfully being employed for the measurement of relative displacement and strain in a simply supported beam experiment. The system utilizes electromagnetic coupling between the transceiver antenna located outside the beam, and the sensing probes placed on the reinforcing bar (rebar) surface inside the beam. The probes were designed in the form of a nested split-ring resonator, a metamaterial-based structure chosen for its compact size and high sensitivity/resolution, which is at µm/microstrains level. Experiments were performed in both the elastic and plastic deformation cases of steel rebars, and the sensing system was demonstrated to acquire telemetric data in both cases. The wireless measurement results from multiple probes are compared with the data obtained from the strain gages, and an excellent agreement is observed. A discrete time measurement where the system records data at different force levels is also shown. Practical issues regarding the placement of the sensors and accurate recording of data are discussed. The proposed sensing technology is demonstrated to be a good candidate for wireless structural health monitoring (SHM) of reinforced concrete members by its high sensitivity and wide dynamic range. © 2016 by the authors; licensee MDPI, Basel, Switzerland

RF displacement and strain sensing system for wireless structural health monitoring

Structural health monitoring (SHM) is a technology with worldwide interest that is vital to ensure the reliability of any structure while also protecting the safety of human life. Over the years, a lot of research has been conducted on this topic, proposing SHM methods that may be instrumental in understanding the condition of critical parts of a structure. These methods generally rely on wired and/or active technologies, which are not preferable since the wires disallow telemetric measurements and mean increased weight and space, while the active technologies require electric power in order to operate. Two of the most important damage indices of a building structure such as a reinforcing bar (rebar) are the strain and displacement forming either with time or a sudden impact like an earthquake. © 2015 IEEE