Optimal Receiver Antenna Location in Indoor Environment Using Dynamic Differential Evolution and Genetic Algorithm

[[abstract]]Using the impulse responses of these multipath channels, the bit error rate (BER) performance for binary pulse amplitude modulation impulse radio ultra-wideband communication system is calculated. The optimization location of receiving antenna is investigated by dynamic differential evolution (DDE) and genetic algorithm (GA) to minimize the outage probability. Numerical results show that the performance for reducing BER and outage probability by DDE algorithm is better than that by GA.[[notice]]補正完畢[[incitationindex]]SCI[[booktype]]紙本[[booktype]]電子

An objective spinal motion imaging assessment (OSMIA): reliability, accuracy and exposure data.

BACKGROUND: Minimally-invasive measurement of continuous inter-vertebral motion in clinical settings is difficult to achieve. This paper describes the reliability, validity and radiation exposure levels in a new Objective Spinal Motion Imaging Assessment system (OSMIA) based on low-dose fluoroscopy and image processing. METHODS: Fluoroscopic sequences in coronal and sagittal planes were obtained from 2 calibration models using dry lumbar vertebrae, plus the lumbar spines of 30 asymptomatic volunteers. Calibration model 1 (mobile) was screened upright, in 7 inter-vertebral positions. The volunteers and calibration model 2 (fixed) were screened on a motorized table comprising 2 horizontal sections, one of which moved through 80 degrees. Model 2 was screened during motion 5 times and the L2-S1 levels of the volunteers twice. Images were digitised at 5fps. Inter-vertebral motion from model 1 was compared to its pre-settings to investigate accuracy. For volunteers and model 2, the first digitised image in each sequence was marked with templates. Vertebrae were tracked throughout the motion using automated frame-to-frame registration. For each frame, vertebral angles were subtracted giving inter-vertebral motion graphs. Volunteer data were acquired twice on the same day and analysed by two blinded observers. The root-mean-square (RMS) differences between paired data were used as the measure of reliability. RESULTS: RMS difference between reference and computed inter-vertebral angles in model 1 was 0.32 degrees for side-bending and 0.52 degrees for flexion-extension. For model 2, X-ray positioning contributed more to the variance of range measurement than did automated registration. For volunteer image sequences, RMS inter-observer variation in intervertebral motion range in the coronal plane was 1.86 degrees and intra-subject biological variation was between 2.75 degrees and 2.91 degrees. RMS inter-observer variation in the sagittal plane was 1.94 degrees. Radiation dosages in each view were below the levels recommended for a plain film. CONCLUSION: OSMIA can measure inter-vertebral angular motion patterns in routine clinical settings if modern image intensifier systems are used. It requires skillful radiography to achieve optimal positioning and dose limitation. Reliability in individual subjects can be judged from the variance of their averaged inter-vertebral angles and by observing automated image registration

Applying Bayesian model averaging for uncertainty estimation of input data in energy modelling

Background Energy scenarios that are used for policy advice have ecological and social impact on society. Policy measures that are based on modelling exercises may lead to far reaching financial and ecological consequences. The purpose of this study is to raise awareness that energy modelling results are accompanied with uncertainties that should be addressed explicitly. Methods With view to existing approaches of uncertainty assessment in energy economics and climate science, relevant requirements for an uncertainty assessment are defined. An uncertainty assessment should be explicit, independent of the assessor’s expertise, applicable to different models, including subjective quantitative and statistical quantitative aspects, intuitively understandable and be reproducible. Bayesian model averaging for input variables of energy models is discussed as method that satisfies these requirements. A definition of uncertainty based on posterior model probabilities of input variables to energy models is presented. Results The main findings are that (1) expert elicitation as predominant assessment method does not satisfy all requirements, (2) Bayesian model averaging for input variable modelling meets the requirements and allows evaluating a vast amount of potentially relevant influences on input variables and (3) posterior model probabilities of input variable models can be translated in uncertainty associated with the input variable. Conclusions An uncertainty assessment of energy scenarios is relevant if policy measures are (partially) based on modelling exercises. Potential implications of these findings include that energy scenarios could be associated with uncertainty that is presently neither assessed explicitly nor communicated adequately

Electoral administration and the problem of poll worker recruitment: Who volunteers, and why?

Elections depend on the thousands of people who give up their time to administer this crucial public service. They staff polling stations and ensure votes are issued, cast and counted. Poll workers are effectively ‘stipended volunteers’, receiving some limited financial compensation, but working for the broader public good. It is important to understand why people choose to give up their time to provide this fundamental public service to their fellow citizens. Using original data from a poll worker survey conducted in the 2015 British general election, this article investigates the motivations and incentives for poll workers volunteering to administer major elections in an important advanced democracy. Exploratory expectations are set out about the motivations of poll workers, and the relationship to their socio-economic characteristics, and levels of social capital and satisfaction with democracy. Contrary to expectations, the findings note that, earning some extra money is important to many, although motivations are more broadly structured around solidary, purposive and material motivations. The article establishes a range of relationships between each set of incentives, and poll workers’ socio-economic, social capital and satisfaction profiles

Income and Health in Cities: the Messages from Stylized Facts

The benefits of good health to individuals and to society are strongly positive, and improving the health of the poor is a key millennium development goal (MDG). A typical health strategy advocated by some calls for increased public spending on health targeted to favor the poor backed by foreign assistance, combined with an international effort to perfect drugs and vaccines to ameliorate the major infectious diseases prevalent in developing nations. However, if the objective is better health outcomes at the least cost and a reduction in urban health inequity, our research suggests that the four most potent policy interventions are: improving access to clean water and sanitation; widely available primary care and health programs aimed at influencing diets and lifestyles; raising the level of education; and better urban land use and transport planning which contains urban sprawl and minimizes the trend towards sedentary living habits. The payoff from these four, in terms of health outcomes especially for those in low-income categories, dwarfs the returns from new drugs and curative hospital-based medicine, although these certainly have their place in a modern urban health system. We find, moreover, that the resource requirements for successful health care policies are likely to depend on an acceleration of economic growth rates, which increase household purchasing power and enlarge the pool of resources available to national and subnational governments to invest in and maintain health-related infrastructure and services. Thus, an acceleration of growth rates may be necessary to sustain a viable urban health strategy, which is equitable, and to ensure steady gains in health outcomes

Social Networks among Elderly Women: Implications for Health Education Practice

The general aim of the present study was to examine and help clarify the properties of the distinctions between social networks and social support, their relationship to health status, and their impli cations for health education practice. More specifically, a secondary data analysis was conducted with 130 white women, community resi dents, between the ages of 60 and 68, which examined the relationship between psychological well-being and social network characteristics. These characteristics are categorized along three broad dimensions: structure—links in the overall network (size and density); interaction— nature of the linkages themselves (frequency, homogeneity, content, reciprocity, intensity, and dispersion); and functions which networks provide (affective support and instrumental support). A combination was made and relative strength investigated of several network char acteristics representative of the quality of interactions (i. e., reciprocal affective support, intensity, and affective support) and those repre senting the quantity of interactions (i.e., size, density, and frequency).Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67277/2/10.1177_109019818301000304.pd