Two-way Link Research Articles

A novel design of physical layer network coding in strong asymmetric two-way relay channels

The quality of two-way links is always asymmetric in practical two-way relay channels (TWRC) and therefore, the capacity of TWRC will be limited by the weaker link. An asymmetric modulation scheme, with physical layer network coding, was presented in order to improve the transmission reliability in TWRC. This makes full use of the stronger link to improve the overall transmission rate and also ensures the reliability of the weaker link. The simulation results show that the proposed asymmetric modulation scheme in the case of strongly asymmetric channels, compared to the symmetric transmission, enhances the system capacity significantly and also guarantees the system reliability.

Streetlife: The Untold History of Europe’s Twentieth Century, by Leif Jerram

As Leif Jerram rightly points out in this book, the past is a ‘messy’ place. When macro-historical events and narratives—policies, broad social and cultural processes and movements and so on—are viewed under a micro(history)scope, they are often shown to have played out not in a neat, linear trajectory but in uneven, incomplete, patchwork and contingent ways. As historians, he seems to suggest, we need to get our hands messier. Largely a synthesis of often very current research, Jerram’s work surveys European urban life in the previous century. It is divided into chapters covering different themes and categories: politics; women; culture; sexuality. A further chapter deviates both from the thematic structure and the viewing of history from the ‘bottom up’; it examines urban planning as ‘the genius of the twentieth century’. Above all, Jerram’s mission (and it does feel like one) is to redress what he sees as historians’ insistence on seeing history as happening at the level of great—and rather impersonal—events and movements, rather than at ground level, in the streets, in the home and to, as well as by, ‘ordinary’ people. He argues that, in our rush to ask ‘who’, ‘why’ and ‘how’ of the past, we have neglected to ask ‘where’; that is, we have ignored that the past took place, literally. He suggests that we need to supplement more conventional historical accounts with a focus on physically locating the past, in the urban streets, squares, dance- and music-halls, bars and nightclubs and on the bodies of the people who inhabited and passed through them. The city is not only the or a key unit of experience—i.e. the ‘level’ at which great global or national events and movements are actually experienced: by focusing our lens on the city, we see both how people used and shaped their environments as well as how they experienced and shaped the policies, practices and ideas that they encountered there, or that were imposed upon them. As he says, there is a ‘two-way link between “high politics” and “street politics”’.

Parents Transmit Happiness Along with Associated Values and Behaviors to Their Children: A Lifelong Happiness Dividend?

There are strong two-way links between parent and child happiness (life satisfaction), even for ‘children’ who have grown up, moved to their own home and partnered themselves. German panel evidence shows that transmission of (un)happiness from parents to children is partly due to transmission of values and behaviors known to be associated with happiness (Headey et al. in Proc Natl Acad Sci 107(42):17922–17926, 2010, in Soc Indic Res doi:10.1007/s11205-012-0079-8,2012). These values and behaviors include giving priority to pro-social and family values, rather than material values, maintaining a preferred balance between work and leisure, active social and community participation, and regular exercise. Both parents have about equal influence on the values and behaviors which children adopt. However, the life satisfaction of adult ‘children’ continues to be directly influenced by the life satisfaction of their mothers, with the influence of fathers being only indirect, via transmission of values and behaviors. There appears to be a lifelong happiness dividend (or unhappiness dividend) due to parenting. Structural equation models with two-way causation indicate that the life satisfaction of offspring can significantly affect the satisfaction of their parents, as well as vice versa, long after the ‘children’ have left home. Data come from 25 waves of the German Socio-Economic Panel Survey (SOEP 1984–2008). SOEP is the only panel survey worldwide in which data on life satisfaction have been obtained from parents and an adequate sub-sample of children no longer living in the parental home.

Multi-objective discrete urban road network design

This paper addresses the problem of designing urban road networks in a multi-objective decision making framework. Given a base network with only two-way links, and the candidate lane addition and link construction projects, the problem is to find the optimal combination of one-way and two-way links, the optimal selection of network capacity expansion projects, and the optimal lane allocations on two-way links to optimize the reserve capacity of the network, and two new travel time related performance measures. The problem is considered in two variations; in the first scenario, two-way links may have different numbers of lanes in each direction and in the second scenario, two-way links must have equal number of lanes in each direction. The proposed variations are formulated as mixed-integer programming problems with equilibrium constraints. A hybrid genetic algorithm, an evolutionary simulated annealing, and a hybrid artificial bee colony algorithm are proposed to solve these two new problems. A new measure is also proposed to evaluate the effectiveness of the three algorithms. Computational results for both problems are presented.

Adjustment Mechanism of Node Transmission Power

As to the power control protocol, in the CPC protocol each node uses the maximum transmit power choosed by all network nodes; the communication consumption of IPC protocol is smaller, but each node is using its own definition of transmission power, two-way link between nodes in the network can not be guaranteed. The sent power control based on data transmission can resolve the defaults of CPC and IPC.

Technology Spillover and Determinants of Foreign Direct Investment: An Analysis of Indian Manufacturing Industries

This paper examines the spillover effect of foreign direct investment (FDI) and determinant of FDI across Indian manufacturing industries. The result, based on two-equation model that allows for the two-way link between labour productivity of locally owned industries and foreign presence provide evidence that foreign presence brings new channels of knowledge and technology spillover to domestic industrial firms. We find that intermediate factors like R&D intensity and technology import intensity can impact positively the productivity of domestic firms. Furthermore, we find that bigger market size and highly productive domestic sectors are likely to attract more foreign capital into Indian industries.

Parents Transmit Happiness Along with Associated Values and Behaviors to their Children - A Lifelong Happiness Dividend?

There are strong two-way links between parent and child happiness (life satisfaction), even for 'children' who have grown up, moved to their own home and partnered themselves. German panel evidence shows that transmission of (un)happiness from parents to children is partly due to transmission of values and behaviors known to be associated with happiness (Headey, Wagner and Muffels, 2010, 2012). These values and behaviors include giving priority to pro-social and family values, rather than material values, maintaining a preferred balance between work and leisure, active social and community participation, and regular exercise. Both parents have about equal influence on the values and behaviors which children adopt. However, the life satisfaction of adult 'children' continues to be directly influenced by the life satisfaction of their mothers, with the influence of fathers being only indirect, via transmission of values and behaviors. There appears to be a lifelong happiness dividend (or unhappiness dividend) due to parenting. Structural equation models with two-way causation indicate that the life satisfaction of offspring can significantly affect the satisfaction of their parents, as well as vice-versa, long after the 'children' have left home. Data come from 25 waves of the German Socio-Economic Panel Survey (SOEP, 1984-2008). SOEP is the only panel survey worldwide in which data on life satisfaction have been obtained from parents and an adequate sub-sample of children no longer living in the parental home.

SUMA

Surface-based brain imaging analysis offers the advantages of preserving the topology of cortical activation, increasing statistical power of group-level statistics, estimating cortical thickness, and visualizing with ease the pattern of activation across the whole cortex. SUMA is an open-source suite of programs for performing surface-based analysis and visualization. It was designed since its inception to allow for a fine control over the mapping between volume and surface domains, and for very fast and simultaneous display of multiple surface models and corresponding multitudes of datasets, all while maintaining a direct two-way link to volumetric data from which surface models and data originated. SUMA provides tools for performing spatial operations such as controlled smoothing, clustering, and interactive ROI drawing on folded surfaces in 3D, in addition to the various level-1 and level-2 FMRI statistics including FDR and FWE correction for multiple comparisons. In our contribution to this commemorative issue of Neuroimage we touch on the importance of surface-based analysis and provide a historic backdrop that motivated the creation of SUMA. We also highlight features that are particular to SUMA, notably the standardization procedure of meshes to greatly facilitate group-level analyses, and the ability to control SUMA's graphical interface from external programs making it possible to handle large collections of data with relative ease.

ALSoD: A user-friendly online bioinformatics tool for amyotrophic lateral sclerosis genetics

Amyotrophic lateral sclerosis (ALS) is the commonest adult onset motor neuron disease, with a peak age of onset in the seventh decade. With advances in genetic technology, there is an enormous increase in the volume of genetic data produced, and a corresponding need for storage, analysis, and interpretation, particularly as our understanding of the relationships between genotype and phenotype mature. Here, we present a system to enable this in the form of the ALS Online Database (ALSoD at http://alsod.iop.kcl.ac.uk), a freely available database that has been transformed from a single gene storage facility recording mutations in the SOD1 gene to a multigene ALS bioinformatics repository and analytical instrument combining genotype, phenotype, and geographical information with associated analysis tools. These include a comparison tool to evaluate genes side by side or jointly with user configurable features, a pathogenicity prediction tool using a combination of computational approaches to distinguish variants with nonfunctional characteristics from disease-associated mutations with more dangerous consequences, and a credibility tool to enable ALS researchers to objectively assess the evidence for gene causation in ALS. Furthermore, integration of external tools, systems for feedback, annotation by users, and two-way links to collaborators hosting complementary databases further enhance the functionality of ALSoD.

Relationships between distributions with certain symmetries

The genesis of two-way links between the inverse Gaussian and Birnbaum–Saunders distributions is explored and extended. The most general results apply to pairs of distributions with a general ‘S-symmetry’ structure involving a self-inverse function closely related to a transformation function with certain properties. These general results arise by transformation from very simple properties of the familiar Azzalini-type skew-symmetric distributions. They specialise again to relationships between R-symmetric and log-symmetric distributions, between various models related to the inverse Gaussian and Birnbaum–Saunders distributions, relationships involving the sinh–arcsinh transformation, and others. Simple random variate generation is a practical consequence of these relationships.

On the Study of Half-Duplex Asymmetric Two-Way Relay Transmission Using an Amplify-and-Forward Relay

This paper studies the information-theoretic metric of outage probability for a half-duplex asymmetric two-way amplify-and-forward (AF) relaying. Unlike current research activities, our main purpose is to examine the impact of traffic asymmetry on system outage probability. First, an exact but two-integral-form outage probability is derived over Rayleigh fading channels. To provide more insight, a closed-form asymptotic outage probability is then obtained. It is shown that the outage probability in the system is determined only by the one-way channel or related to the two-way links, depending on the asymmetric level of the two senders' target rates and the terminals' average transmission powers. Following this analysis, optimum power allocation and opportunistic relay selection are studied to optimize the overall performance of the considered AF scenario. Next, with the aid of traffic knowledge, novel power allocation and relay selection criteria are proposed, followed by an analysis of the outage probability with the relay selection. Simulation experiments are performed to validate the proposed studies in this paper. The results show that the proposed power allocation and relay selection methods can achieve significant performance gains in terms of outage probability, regardless of symmetric or asymmetric traffic and channels.

Parents Transmit Happiness Along with Associated Values and Behaviors to Their Children: A Lifelong Happiness Dividend?

There are strong two-way links between parent and child happiness (life satisfaction), even for 'children' who have grown up, moved to their own home and partnered themselves. German panel evidence shows that transmission of (un)happiness from parents to children is partly due to transmission of values and behaviors known to be associated with happiness (Headey, Wagner and Muffels, 2010, 2012). These values and behaviors include giving priority to pro-social and family values, rather than material values, maintaining a preferred balance between work and leisure, active social and community participation, and regular exercise. Both parents have about equal influence on the values and behaviors which children adopt. However, the life satisfaction of adult 'children' continues to be directly influenced by the life satisfaction of their mothers, with the influence of fathers being only indirect, via transmission of values and behaviors. There appears to be a lifelong happiness dividend (or unhappiness dividend) due to parenting. Structural equation models with two-way causation indicate that the life satisfaction of offspring can significantly affect the satisfaction of their parents, as well as vice-versa, long after the 'children' have left home. Data come from 25 waves of the German Socio-Economic Panel Survey (SOEP, 1984-2008). SOEP is the only panel survey worldwide in which data on life satisfaction have been obtained from parents and an adequate sub-sample of children no longer living in the parental home.

A New Perspective to Integrated Satellite Navigation Systems

In order to further expand and enhance the level of applications of satellite navigation, three new systems are proposed on the basis of successful application of existing satellite navigation systems: a two-way satellite communication and navigation system which is based on a two-way satellite communication transmission link, a satellite-assisted ground mobile communication and navigation system and an air–ground communication cooperation multi-system multi-mode positioning system. Key technologies for achieving breakthroughs and implementation of the three new systems are also described, including deep integration of navigation signals and communication signals, a compared measurement technique, and our method to improve constellation GDOP. Some applications of these new systems, in the fields of high-precision measurement, emergency rescue and equipment real-time monitoring, are introduced.

Outage performance of amplify-and-forward two-way relaying with asymmetric traffics

This letter conducts the outage analysis for an amplify-and-forward (AF) based two-way relaying by jointly considering outage events at the two senders with asymmetric traffics. Unlike the current research activities, our goal is to explore the impact of traffic asymmetry on the system outage probability. We first derive the exact expressions of outage probability for the AF scenario over Rayleigh fading channels. To gain more insight, approximated expressions are developed at high signal-to-noise ratio (SNR) region. After that we interestingly find that the asymmetry of system traffics has significant impact on the system outage probability and the outage probability in the system is determined only by the one-way channel or related simultaneously to the two-way links, depending on the level of asymmetry between the two senders’ information rates. Simulation experiments are done. The simulation results verify our propositions and validate the accuracy of our derived expressions.

The Casual Relations Between the Economic Growth and Financial Development in Greece: An Empirical Research for the Causality Analysis

The main object of this research focuses on the empirical study of the causal relation among the degree of openness of the economy, the financial and economic growth using a multi-variate autoregressive model VAR. The long-term relation among GDP, the financial development and the degree of openness of the economy are based on the Cointegration test results. The Granger causality test, using the Vector Autoregration Estimate and the error correction model, suggests that there is a dynamic two-way causal link between the variables GDP and OPEN. In addition, there is an one way causal link between the variables GDP and FD and finally we observed an one way causal link between the variables OPEN and FD.

Using successful graduates to improve the quality of undergraduate nursing programs

This paper outlines the context and focus of the late 2008 survey of 45 early career nursing graduates working in public hospitals in an outer-urban area of Sydney who were identified by their supervisors as performing successfully. It gives an overview of the key quantitative and qualitative results for 2008 compared with the results of earlier studies of successfully performing nurses and other professionals in the first 3-5 years of their career. Based on this analysis it makes a range of recommendations on how to optimise the quality and relevance of the learning design, support and assessment systems experienced by undergraduate nursing students.
 The study confirms that, in addition to possessing a high level of technical competence, it is a particular combination of personal, interpersonal and cognitive capabilities which characterises the most effective performers. The most productive approaches to developing these capabilities focus on: consistent two-way links between theory and practice; the availability of responsive, committed academic staff with current clinical experience; provision of clear direction and integration between different units of study; the systematic use of case-based learning, simulations, clinical placements and associated assessment tasks which are a "real world" focused, integrated and problem-based, and which concentrate on the key capabilities identified as counting most for successful early career practice in this and parallel studies.

Education, Human Development and Economic Growth in Punjab: A Causal Analysis

This paper has evaluated the relative performance of 12 major districts of Punjab in terms of Human Development and Economic Growth and examined the two-way link between them during 1981-2001. Expectation of life at birth positively but non-significantly affected inter-district variations in EG. For EG induced HD, per capita NDP negatively and significantly affected inter district variations in literacy rate and positively and non-significantly affected inter-district variations of life expectancy. Classification of districts based on their performance on HD and EG reveals that out of 12 districts, only four districts were in the category of lopsided HD and six districts were in the category of virtuous cycle as per the indicators of HD (HDI, literacy rate and expectation of life at birth) in 2001. The results suggest that the policy should be such that HD induced growth process is strengthened for lifting the districts to the virtuous cycle category.

Private Credit Development and Economic Growth In Transition Economies

This research compares the links between the economic growth and the development of banking credit for the private sector in three transition economies. The empirical results confirm the choice of a case-by-case analytical and time series econometrical approach. Each country has its own specificities which justify the established long-run positive two-way link between the real and financial sector in Poland, the positive link going from the real sector towards the private credit development in the case of Hungary, and the negative two-way link between the two sectors in the case of the Czech Republic. We explain those particularities by the different methods of banking sector privatization, the different approaches for solving the bad credit problems, and the different attitudes towards banking FDI. The comparison between the experiences of these three countries underlines the importance of adequately supporting and regulating the emerging banking sectors in lower-income transition economies when designing growth-promoting economic policies on the road to EU accession.

Fast MRI coil analysis based on 3-D electromagnetic and RF circuit co-simulation

To accelerate the analysis of a multi-element MRI coil, a two-way link is used between radiofrequency (RF) circuit and 3-D electromagnetic (EM) simulation tools. In this configuration, only one 3-D EM simulation is required to investigate the coil performance over a range of different tunings, saving considerable computation time. For the purpose of 3-D EM simulation, the coil feed networks and trim capacitors are substituted by 50Ω ports. The entire coil was tuned in the RF circuit domain, and the near-field profiles of the electric and magnetic field components were then calculated, together with the specific energy absorption ratio (SAR) maps in the 3-D EM domain

Quantifying leaf venation patterns: two‐dimensional maps

The leaf vasculature plays crucial roles in transport and mechanical support. Understanding how vein patterns develop and what underlies pattern variation between species has many implications from both physiological and evolutionary perspectives. We developed a method for extracting spatial vein pattern data from leaf images, such as vein densities and also the sizes and shapes of the vein reticulations. We used this method to quantify leaf venation patterns of the first rosette leaf of Arabidopsis thaliana throughout a series of developmental stages. In particular, we characterized the size and shape of vein network areoles (loops), which enlarge and are split by new veins as a leaf develops. Pattern parameters varied in time and space. In particular, we observed a distal to proximal gradient in loop shape (length/width ratio) which varied over time, and a margin-to-center gradient in loop sizes. Quantitative analyses of vein patterns at the tissue level provide a two-way link between theoretical models of patterning and molecular experimental work to further explore patterning mechanisms during development. Such analyses could also be used to investigate the effect of environmental factors on vein patterns, or to compare venation patterns from different species for evolutionary studies. The method also provides a framework for gathering and overlaying two-dimensional maps of point, line and surface morphological data.