High resolution spherical microwave holography

A practical technique is developed to determine the electric and/or magnetic field on objects and sources inside a spherical measurement surface. The technique, known as spherical microwave holography (SMH), provides a nondestructive, nonintrusive method of point-by-point evaluation of antennas and radomes over their spatial extent. The resolution capability of SMH is developed and demonstrated by measurements. Resolution in SMH is only limited by the measurement system's capabilities. Dielectric and metallic obstacles on the surface of a radome are located and identified. Resolution as small as 0.33λ₀ is demonstrated     

How entrepreneurial practices balance art and business: Insights into creative entrepreneurship in the European film industry

Relying on the literature on tensions and contradictions and the theory of practice, coupled with the literature on creative industries, this study uncovers how creative entrepreneurs balance the tension between art and business and respond to other challenges of creative entrepreneurship. The multiple case studies method is adopted by examining founders, cofounders and main employees of European film production companies. We reveal the perception of creative entrepreneurs towards the relationship between art and business. We explore different organizational and industry-level challenges experienced by creative entrepreneurs and uncover the organizational practices they adopt to deal with the identified challenges. The research contributes to the phenomenon of creative entrepreneurship by introducing the practice perspective, to the literature on paradox and contradiction by exploring the micro-foundations of tensions and paradox responses in high-intensity situations and to practice-based studies by investigating a domain-specific practice theory and highlighting the agency of creative entrepreneurs in adapting practices necessary to deal with conflicting demands of creative entrepreneurship.     

Comparative study on classifying human activities with miniature inertial and magnetic sensors

This paper provides a comparative study on the different techniques of classifying human activities that are performed using body-worn miniature inertial and magnetic sensors. The classification techniques implemented and compared in this study are: Bayesian decision making (BDM), a rule-based algorithm (RBA) or decision tree, the least-squares method (LSM), the k-nearest neighbor algorithm (k-NN), dynamic time warping (DTW), support vector machines (SVM), and artificial neural networks (ANN). Human activities are classified using five sensor units worn on the chest, the arms, and the legs. Each sensor unit comprises a tri-axial gyroscope, a tri-axial accelerometer, and a tri-axial magnetometer. A feature set extracted from the raw sensor data using principal component analysis (PCA) is used in the classification process. A performance comparison of the classification techniques is provided in terms of their correct differentiation rates, confusion matrices, and computational cost, as well as their pre-processing, training, and storage requirements. Three different cross-validation techniques are employed to validate the classifiers. The results indicate that in general, BDM results in the highest correct classification rate with relatively small computational cost.     

Investigation of Magnetic Properties of Phase Transformations in Copper-Based Alloys

In this study, the magnetic properties of both Cu_85.41Al_9.97Mn_4.62 and Cu_82.41Mn_13.81Al_3.78 (wt%) shape memory alloys were studied. The analysis of the magnetization as a function of applied field and temperature was conducted between ?10 to 10 T magnetic field ranges at constant temperature. Two alloys were examined using ac magnetic susceptibility measurements. The magnetic saturation values at room temperature were found to be approximately 1 and 70 emu/g for Cu_85.41Al_9.97Mn_4.62 (wt%) and Cu_82.41Mn_13.81Al_3.78 (wt%) alloys, respectively. The magnetic saturation and the coercivity values for the CuAlMn alloy are found smaller than those for the CuMnAl alloy. Moreover, from the magnetization curves, the typical ferromagnetic behavior were observed for both alloys. Details of the morphological properties and chemical composition have been examined by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX), respectively.     

Airline planning benchmark problems—Part I:: Characterising networks and demand using limited data

This paper is the first of two papers entitled “Airline Planning Benchmark Problems”, aimed at developing benchmark data that can be used to stimulate innovation in airline planning, in particular, in flight schedule design and fleet assignment. While optimisation has made an enormous contribution to airline planning in general, the area suffers from a lack of standardised data and benchmark problems. Current research typically tackles problems unique to a given carrier, with associated specification and data unavailable to the broader research community. This limits direct comparison of alternative approaches, and creates barriers of entry for the research community. Furthermore, flight schedule design has, to date, been under-represented in the optimisation literature, due in part to the difficulty of obtaining data that adequately reflects passenger choice, and hence schedule revenue. This is Part I of two papers taking first steps to address these issues. It does so by providing a framework and methodology for generating realistic airline demand data, controlled by scalable parameters. First, a characterisation of flight network topologies and network capacity distributions is deduced, based on the analysis of airline data. Then a multi-objective optimisation model is proposed to solve the inverse problem of inferring OD-pair demands from passenger loads on arcs. These two elements are combined to yield a methodology for generating realistic flight network topologies and OD-pair demand data, according to specified parameters. This methodology is used to produce 33 benchmark instances exhibiting a range of characteristics. Part II extends this work by partitioning the demand in each market (OD pair) into market segments, each with its own utility function and set of preferences for alternative airline products. The resulting demand data will better reflect recent empirical research on passenger preference, and is expected to facilitate passenger choice modelling in flight schedule optimisation.     

Determination of important biochemical properties of honey to discriminate pure and adulterated honey with sucrose (Saccharum officinarum L.) syrup

The aims of the present study were to determine biochemical properties of honey samples and to discriminate pure and adulterated honey produced by the standard bee feeding method (control honey), the shaking method (pure blossom honey), and overfeeding (100 kg/colony syrup) with sucrose syrup (adulterated honey). The biochemical properties evaluated were moisture, ash, acidity, hydroxymethylfurfural (HMF), specific sugars (i.e. fructose, glucose, fructose–glucose, sucrose, and maltose), diastase activity, δ¹³C value (honey), δ¹³C value (protein), electrical conductivity, potassium, vitamin C, and proline. Fifteen honey samples were analyzed by discriminant analysis stepwise method. Proline, electrical conductivity and sucrose were found as discriminative characters of samples. Based on these three properties 100% of original group cases (samples) correctly classified in their real group. We found that the honey produced by feeding with 100 kg sucrose syrup per colony contained the sucrose as low as pure blossom honey. Therefore, the sugar (sucrose, fructose and glucose) content of honey cannot be used to distinguish between adulterated (sucrose syrup) and pure blossom honey.     

Quantification of Market Performance as a Function of System Security

The tight coupling between market and system operations in the restructured environment requires a thorough understanding of the interdependence between the market performance and the way the power systems are operated. In particular, we need to go beyond the qualitative characterization and to quantify the dependence of the market performance on the system security. Such studies are typically not performed in today's regional transmission organization, or RTO, structures. In this paper, we develop a general approach to quantify the monetary impacts of complying with a specified security criterion when the deployment of appropriate preventive and/or corrective security control actions is fully taken into account. This approach is deployed in the day-ahead electricity markets and is based on the emulation of the way the RTO currently operates the market and the grid, the latter in compliance with the security criterion. The proposed approach has a wide range of applications such as comparative market performance assessments of different security criteria and the cost/benefit analysis of network improvements to mitigate the market performance impacts of a set of specified contingencies. We illustrate the application of the proposed approach on the large-scale ISO-NE system to quantify the monetary impacts associated with changing from the current security criterion to two other criteria using the actual 2005 day-ahead data-the historical system model and the bids/offers submitted-with the actual market clearing methodology. These studies capture, in a meaningful way, the impacts of the changes with respect to the current security criterion. An important finding of this study is that the economic efficiency of electricity markets need not decrease when the system is operated under a stricter criterion.     

Antenatal fetal risk assessment using a neurofuzzy technique

This study defines an intelligent neurofuzzy system for antepartum fetal evaluation, The task is to investigate the Doppler ultrasound measurements of the umbilical artery (UA) and the cerebral artery (CA) to relate the health conditions of fetuses. We thus use the UA blood flow velocity waveforms [pulsality index, resistance index, and systolic/diastolic ratio] and the ratios of cerebral-umbilical resistance indices in terms of weeks. We then make a decision on the basis of a fuzzy-rule-based system combined with data-based learning strategies such as a radial basis function network and a multilayer perceptron for assessing the hypoxia suspicion. A fuzzy grade of membership is used for the evaluation of the seriousness of the situation of the fetus, and the diagnostic interpretations for doctors such as good, suspicious, and alarming conditions of fetus are derived     

Antenatal fetal risk assessment by blood-flow velocity waveforms

The purpose of this article is to study a system for antepartum fetal evaluation. The task is to investigate the Doppler ultrasound measurements of the umbilical artery and the cerebral artery to relate the health status of a fetus by using discriminant functions of pattern recognition. The authors then analyze the individual effects of various blood-flow velocity waveforms using principal component analysis.