Creation of reduced fat foods: Influence of calcium-induced droplet aggregation on microstructure and rheology of mixed food dispersions

The impact of calcium-induced fat droplet aggregation on the microstructure and physicochemical properties of model mixed colloidal dispersions was investigated. These systems consisted of 2 wt% whey protein-coated fat droplets and 4 wt% modified starch granules heated to induce starch swelling (pH 7). Optical and confocal microscopy showed that the fat droplets were dispersed within the interstitial region between the swollen starch granules. The structural organisation of the fat droplets within these interstitial regions could be modulated by controlling the calcium concentration: (i) at a low calcium concentration the droplets were evenly distributed; (ii) at an intermediate calcium concentration they formed a layer around the starch granules; (iii) at a high calcium concentration they formed a network of aggregated droplets. Paste-like materials were produced when the fat droplets formed a three-dimensional network in the interstitial region. The properties of fat droplet–starch granule suspensions can be modulated by altering the electrostatic interactions to alter microstructure.     

A rotor lamination design for surface permanent magnet retention athigh speeds

A major problem in the design and manufacturing of surface mounted permanent magnet machines is reliably holding the permanent magnets in place at high speeds. This paper evaluates a unique rotor lamination design for a high pole number, permanent magnet alternator. This buried magnet design, which is capable of reliably holding the permanent magnets in place at high speeds, offers both easier and cheaper assembly when compared with the methods currently used in surface mounted permanent magnet machines. Finite element analysis is used to compare the buried magnet design with equivalent surface mounted designs and shows that the performance of the alternator is not significantly affected by the iron over the magnets. Experimental results from a prototype alternator further corroborate the FEA and show that the design is capable of operating at high speeds with no other means of magnet retention. In addition, an improvement in the buried magnet design which can reduce the lamination complexity is suggested and examined     

Analysis and design of current regulators using complex vectors

The analysis and design of current regulators for multiphase AC loads in AC machines is presented using complex vector notation. The use of complex vector notation provides a way of comparing the performance of controller topologies through their complex vector root locus and complex vector frequency-response functions. Limitations in the performance of the synchronous frame proportional plus integral current regulator are outlined and several ways of improving its performance are suggested and investigated     

Symptom distress in adult patients with cancer

Symptom distress in the adult population with cancer is of concern to clinicians who care for these patients. Increased research has been directed toward the development and refinement of symptom distress scales, the identification of determinants of symptom distress, the investigation of symptom distress as a predictor, and the examination of the relationship between quality of life and symptom distress. Findings from this research have increased our understanding of symptom distress in adult patients with cancer. However, a major limitation of work to date has been a lack of consensus related to the definition and measurement of the symptom distress construct. The purpose of this article is to address existing conceptual and methodological challenges inherent in the study of symptom distress, and to make recommendations for further research in this area.     

Temperature Estimation in Inverter-Fed Machines Using High-Frequency Carrier Signal Injection

Temperature monitoring using the injection of a high-frequency carrier signal voltage is proposed in this paper. The carrier signal voltage is used to estimate the transient impedance of the system, which is a function of the stator transient resistance and, therefore, the windingspsila temperature. The variation of the stator transient impedancepsilas phase angle is used to track the temperature of the stator windings. The method can be implemented in standard inverter-fed drives with no additional hardware, with minimal computational requirements, and with practically no interference with the regular operation of the drive.     

Relationships Between Fructans Content and Barley Malt Quality

Fructans are fructose polymers derived from sucrose and like starch are naturally present in many plants as reserve carbohydrates. The aims of this study were to determine the content of fructans in both grain and malt barley samples and to examine the relationships between fructan content and malt quality parameters such as hot water extract (HWE), apparent attenuation limit (AAL) and viscosity. The relationships between fructan content and malt quality parameters were first investigated using Pearson correlations. A positive and statistically significant (p?<?0.05) correlation between fructan content and HWE (r?=?0.73) and a negative and statistically significant with viscosity (r?=??0.45) was found; however, there was no relationship between fructan content and AAL in the malt sample set analysed. The results from this study showed that diverse barley varieties have different fructan contents in grain and corresponding malt which may determine differences in final malt quality.     

Stator Windings Fault Diagnostics of Induction Machines Operated From Inverters and Soft-Starters Using High-Frequency Negative-Sequence Currents

This paper studies the application of high-frequency voltage excitation-based stator winding diagnostic methods to three-phase ac machines operated from power converters that create the necessary high-frequency excitation as part of their normal operation. This paper focuses on two specific operating modes: 1) machines operated from inverters in the overmodulation region and 2) machines operated from soft-starters during startup. In both cases, high-frequency (in the range of the hundred hertz) voltage components at well-defined frequencies are created. The negative-sequence currents induced from these high-frequency voltages are shown to contain accurate information on the level of asymmetry (fault) in the machine. This information is significantly richer than exists in other modes of operation, i.e., inverters working in the linear modulation region or soft-starters in the steady state, and provides interesting opportunities to complement other diagnostic methods.     

The Effect of the Addition of Emulsifiers on the Pasting Properties of Barley Grain and Malt

The characteristics of the starch granule such as swelling, breakdown and retrogradation in large determines the texture and stability of starchy foods. However, other characteristics of the grain and/or the presence or addition of chemical compounds to the grain/food matrix can modify or alter these properties. The aim of this study was to evaluate the effect of the addition of an emulsifier (Tween 20 and 80) on the pasting properties of barley grain and malt using the rapid visco analyser (RVA). A decrease in peak viscosity (PV, cP), breakdown (B, cP) and final viscosity (FV, cP), while an increase in time to peak (TTP, min) and pasting temperature (PT, °C) as consequence of the addition of Tween 20 was observed. However, this trend was not the same for all the varieties analysed. Overall, these results showed that complex between sugars and lipids are present in barley flour and malt. The practical implications of this study are related with the fact that starch alone (amylose and amylopectin) might not be necessarily the only main driver of malt quality in barley.     

Position estimation in induction machines utilizing rotor bar slotharmonics and carrier-frequency signal injection

This paper presents a simple and robust way of utilizing harmonic saliencies created by rotor and stator slotting, present in some induction machine designs, for the estimation of rotor position. The injection of a carrier-signal voltage, in addition to the fundamental excitation, produces a carrier-signal current that contains the desired spatial information. A closed-loop tracking observer is then used to extract this spatial information for the estimation of the rotor position. Due to its reliance on a spatial saliency and carrier-frequency signal injection, the technique is very robust over a wide speed range, including low and zero speed     

Assessing the maximum fuel savings obtainable in simple wind-diesel systems

We present a statistical method to derive the upper limit of the obtainalbe fuel savings in simple wind-diesel systems applying fixed control rules. The fuel savings when using the optimal control may be estimated from the statistical properties of the time series of the power balance: wind turbine power-load. The method is validated by comparison with a time step simulation of the system. We found out that the fuel savings which may be obtained with a simple persistence based control are close to the optimal values. Using this method the dependence of the fuel savings on the wind climate and the turbulence characteristics at the site may be obtained easily. These results are also compared to the performance data of systems with energy storage.