Computationally Efficient Optimization of a Five-Phase Flux-Switching PM Machine Under Different Operating Conditions

This paper investigates the comparative design optimizations of a five-phase outer-rotor flux-switching permanent magnet (FSPM) machine for in-wheel traction applications. To improve the comprehensive performance of the motor, two kinds of large-scale design optimizations under different operating conditions are performed and compared, including the traditional optimization performed at the rated operating point and the optimization targeting the whole driving cycles. Three driving cycles are taken into account, namely, the urban dynamometer driving schedule (UDDS), the highway fuel economy driving schedule (HWFET), and the combined UDDS/HWFET, representing the city, highway, and combined city/highway driving, respectively. Meanwhile, the computationally efficient finite-element analysis (CE-FEA) method, the cyclic representative operating points extraction technique, as well as the response surface methodology (in order to minimize the number of experiments when establishing the inverse machine model), are presented to reduce the computational effort and cost. From the results and discussion, it will be found that the optimization results against different operating conditions exhibit distinct characteristics in terms of geometry, efficiency, and energy loss distributions. For the traditional optimization performed at the rated operating point, the optimal design tends to reduce copper losses but suffer from high core losses; for UDDS, the optimal design tends to minimize both copper losses and PM eddy-current losses in the low-speed region; for HWFET, the optimal design tends to minimize core losses in the high-speed region; for the combined UDDS/HWFET, the optimal design tends to balance/compromise the loss components in both the low-speed and high-speed regions. Furthermore, the advantages of the adopted optimization methodologies versus the traditional procedure are highlighted

Evaluation of the Synergistic Effect of Amikacin with Cefotaxime against <em>Pseudomonas aeruginosa</em> and Its Biofilm Genes Expression

A total of 100 broiler chickens were examined for the presence of Pseudomonas aeruginosa by standard microbiological techniques. Susceptibility pattern for amikacin and cefotaxime was performed by Kirby-Bauer and microdilution assays. Then, checkerboard titration in trays was applied and FIC was measured to identify the type of interaction between the two antibiotics. The ability of isolates to form in vitro biofilm was detected by two methods, one qualitative (CRA) and the other quantitative (MTP), followed by investigating the effect of each antibiotic alone and in combination on the expression of biofilm genes. The overall isolation percentage of P. aeruginosa was 21%. Resistance to each antibiotic was more than 50%; the range of cefotaxime MIC was 8–512 μg/ml, while amikacin MIC range was 1–64 μg/ml. The FIC index established a synergistic association between tested two drugs in 17 (81%) of isolates and the remaining represent partially synergism. The qualitative technique showed that only 66.6% of the isolates were considered biofilm producers, while the quantitative technique showed that 90.4% of the isolates were biofilm producers. Further to RT-PCR investigation, significant repression against biofilm-forming genes (filC, pelA, and pslA) was observed for the combination of antibiotics when compared with monotherapy

Comparison and Design Optimization of a Five-Phase Flux-Switching PM Machine for In-Wheel Traction Applications

A comparative study of five-phase outer-rotor flux-switching permanent magnet (FSPM) machines with different topologies for in-wheel traction applications is presented in this paper. Those topologies include double-layer winding, single-layer winding, C-core, and E-core configurations. The electromagnetic performance in the low-speed region, the flux-weakening capability in the high-speed region, and the fault-tolerance capability are all investigated in detail. The results indicate that the E-core FSPM machine has performance advantages. Furthermore, two kinds of E-core FSPM machines with different stator and rotor pole combinations are optimized, respectively. In order to reduce the computational burden during the large-scale optimization process, a mathematical technique is developed based on the concept of computationally efficient finite-element analysis. While a differential evolution algorithm serves as a global search engine to target optimized designs. Subsequently, multiobjective tradeoffs are presented based on a Pareto-set for 20 000 candidate designs. Finally, an optimal design is prototyped, and some experimental results are given to confirm the validity of the simulation results in this paper

Mining photographic collections to enhance the precision and recall of search results using semantically controlled query expansion

Driven by a larger and more diverse user-base and datasets, modern Information Retrieval techniques are striving to become contextually-aware in order to provide users with a more satisfactory search experience. While text-only retrieval methods are significantly more accurate and faster to render results than purely visual retrieval methods, these latter provide a rich complementary medium which can be used to obtain relevant and different results from those obtained using text-only retrieval. Moreover, the visual retrieval methods can be used to learn the user’s context and preferences, in particular the user’s relevance feedback, and exploit them to narrow down the search to more accurate results. Despite the overall deficiency in precision of visual retrieval result, the top results are accurate enough to be used for query expansion, when expanded in a controlled manner. The method we propose overcomes the usual pitfalls of visual retrieval: 1. The hardware barrier giving rise to prohibitively slow systems. 2. Results dominated by noise. 3. A significant gap between the low-level features and the semantics of the query. In our thesis, the first barrier is overcome by employing a simple block-based visual features which outperforms a method based on MPEG-7 features specially at early precision (precision of the top results). For the second obstacle, lists from words semantically weighted according to their degree of relation to the original query or to relevance feedback from example images are formed. These lists provide filters through which the confidence in the candidate results is assessed for inclusion in the results. This allows for more reliable Pseudo-Relevance Feedback (PRF). This technique is then used to bridge the third barrier; the semantic gap. It consists of a second step query, re-querying the data set with an query expanded with weighted words obtained from the initial query, and semantically filtered (SF) without human intervention. We developed our PRF-SF method on the IAPR TC-12 benchmark dataset of 20,000 tourist images, obtaining promising results, and tested it on the different and much larger Belga benchmark dataset of approximately 500,000 news images originating from a different source. Our experiments confirmed the potential of the method in improving the overall Mean Average Precision, recall, as well as the level of diversity of the results measured using cluster recall

Pozitivan učinak L-karnitina na imuno- metabolički odgovor i antioksidacijski status u koza s gravidnosnom toksemijom

According to the literature, there have been limited studies describing the efficacy of L-carnitine (LC) administration in goats. The present study was designed to evaluate the influence of orally administered LC on some immune- metabolic variables, as well as the redox status in goats with experimentally induced pregnancy toxemia (PT). The study included eighteen clinically healthy Baladi goats at 110 ± 5 days of gestation. The animals were randomly allocated into three equally-sized groups: control, toxemic (PT), and toxemic treated with LC (TLC). On day 110 ± 5 of gestation, the goats in the TLC group received 10 mL of LC given as an oral drench once daily. Administration of LC was continued for 20 consecutive days. At day 130 of gestation, PT was experimentally induced in the animals of the PT and TLC groups by means of feed withdrawal for 72 hours. For biochemical analyses, blood samples were collected from each investigated doe via jugular vein puncture before PT induction (T0), and once daily for five consecutive days (T1, T2, T3, T4, and T5). The clinical findings of PT appeared in all the goats of the PT group after 72 hours of feed withdrawal, while the goats of the TLC group did not show any clinical symptoms throughout the study period. Administration of LC elicited initial and sustained low serum levels of malondialdehyde (MDA), tumor necrosis factor (TNF-α), and high serum glucose, superoxide dismutase (SOD) and interleukin (IL)-10 at T0 compared with those of the control and PT groups. At T3, goats that received LC showed significantly lower values of β-hydroxybutyric acid, non-esterified fatty acid, triacylglycerols, MDA, TNF-α, IL-1β, IL-6, and higher values of total cholesterol, glutathione peroxidase, SOD, and IL-10 than those of the PT group. Our data suggest that orally administered LC could be useful in ameliorating the immune status and improving lipid metabolism in goats with PT.Prema podacima iz literature postoji ograničen broj istraživanja primjene L-karnitina (LK) u koza. Cilj ovog rada bio je procijeniti učinak oralno primijenjenog LK-a na određene imuno-metaboličke pokazatelje i redoksni status u koza u kojih je eksperimentalno izazvana gravidnosna tokesmija (GT). Istraživanje je uključilo 18 klinički zdravih koza baladi pasmine čija je gravidnost iznosila 110 ± 5 dana. Životinje su nasumično podijeljene u tri jednake skupine: kontrolnu, toksemijsku (GT) i toksemijsku kojoj je davan LK (TLK). Koze u skupini TLK su od 110. ± 5 dana gravidnosti jedanput dnevno dobivale 10 mL LK-a oralnom drenčer špricom. Primjena LK-a nastavljena je sljedećih dvadeset dana uzastopno. Na 130. dan gravidnosti GT je eksperimentalno izazvan u skupinama GT i TLK, uz uskraćivanje hrane tijekom 72 sata. U svake je koze iz jugularne vene uzeta krv za biokemijsku analizu prije izazivanja GT-a (T0) i jedanput dnevno sljedećih pet dana (T1, T2, T3, T4 i T5). Klinički je GT ustanovljen u svih koza u skupini GT 72 sata nakon što im je uskraćena hrana, dok koze iz skupine TLK nisu pokazale kliničke simptome za vrijeme istraživanja. Primjena LK-a prouzročila je niske serumske vrijednosti malondialdehida (MDA), faktora tumorske nekroze (TNF-α) i visoke serumske vrijednosti glukoze, superoksidne dismutaze (SOD) i interleukina (IL)- 10 prije izazivanja GT-a (T0) u usporedbi s kontrolnom i GT skupinom. Treći dan (T3) koze koje su primile LK pokazale su znakovito niže vrijednosti β-hidroksimaslačne kiseline, neesterificirane masne kiseline, triacilglicerola, MDA-a, TNF-α, IL-1β, IL-6 te veće vrijednosti ukupnog kolesterola, glutation-peroksidaze, SOD-a i IL-10 od onih u skupini GT. Rezultati su pokazali da bi oralno primijenjen LK mogao pridonijeti poboljšanju imunosnog statusa i metabolizma masnoća u koza s GT-om

Digital Resources to Enhance Creative Mathematical Thinking in a Biomathematics Context

International audienceIn this research, we present the design of digital resources, carried out within the framework of the MC Squared project (http://mc2-project.eu). These resources are the so-called " c-book units " (" c " for creative), which are digital books produced within a socio-technological environment allowing meshing narratives with interconnected, interactive and dynamic digital artefacts (widgets), to enhance Creative Mathematical Thinking. We illustrate the design of a c-book unit within a biomathematics context aimed at enhancing creative mathematical thinking using a wide range of digital widgets

Effect of taurine supplementation on hyperhomocysteinemia and markers of oxidative stress in high fructose diet induced insulin resistance

<p>Abstract</p> <p>Background</p> <p>High intake of dietary fructose is accused of being responsible for the development of the insulin resistance (IR) syndrome. Concern has arisen because of the realization that fructose, at elevated concentrations, can promote metabolic changes that are potentially deleterious. Among these changes is IR which manifests as a decreased biological response to normal levels of plasma insulin.</p> <p>Methods</p> <p>Oral glucose tolerance tests (OGTT) were carried out, homeostasis model assessment of insulin resistance (HOMA) was calculated, homocysteine (Hcy), lipid concentrations and markers of oxidative stress were measured in male <it>Wistar </it>rats weighing 170-190 g. The rats were divided into four groups, kept on either control diet or high fructose diet (HFD), and simultaneously supplemented with 300 mg/kg/day taurine via intra-peritoneal (i.p.) route for 35 days.</p> <p>Results</p> <p>Fructose-fed rats showed significantly impaired glucose tolerance, impaired insulin sensitivity, hypertriglyceridemia, hypercholesterolemia, hyperhomocysteinemia (HHcy), lower total antioxidant capacity (TAC), lower paraoxonase (PON) activity, and higher nitric oxide metabolites (NOx) concentration, when compared to rats fed on control diet. Supplementing the fructose-fed rats with taurine has ameliorated the rise in HOMA by 56%, triglycerides (TGs) by 22.5%, total cholesterol (T-Chol) by 11%, and low density lipoprotein cholesterol (LDL-C) by 21.4%. Taurine also abolished any significant difference of TAC, PON activity and NOx concentration among treated and control groups. TAC positively correlated with PON in both rats fed on the HFD and those received taurine in addition to the HFD. Fructose-fed rats showed 34.7% increase in Hcy level. Taurine administration failed to prevent the observed HHcy in the current dosage and duration.</p> <p>Conclusion</p> <p>Our results indicate that HFD could induce IR which could further result in metabolic syndrome (MS), and that taurine has a protective role against the metabolic abnormalities induced by this diet model except for HHcy.</p

A thermochemistry and kinetic study on the thermal decomposition of ethoxyquinoline and ethoxyisoquinoline

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Quantum chemical calculations were used to study the production of ethylene and keto/enol tautomers from ethoxyquinoline (2‐EQ) and ethoxyisoquinoline (1‐EisoQ and 3‐EisoQ) in the gas phase and ethanol at the MP2/6‐311++G(2d,2p)//BMK/6‐31+G(d,p) level. The obtained data indicate that the elimination of ethylene from 1‐EisoQ and 2‐EQ is slightly more favorable than from 3‐EisoQ. Formation of quinolone and isoquinolone (2‐EQO, 1‐EisoQO, and 3‐EisoQO) is kinetically favored compared to their enols. Decomposition of 2‐EQ and 1‐EisoQ to ethylene and keto forms is thermodynamically and kinetically preferable more stable than the corresponding enols. However, the hydroxy form of 3‐EisoQ is more stable than its keto tautomer in the gas phase and ethanol. The enol tautomers cost less energy when formed from their keto forms rather than from the parent ethoxyquinolone and ethoxyisoquinoline

Atmospheric Oxidation of Methyl Propanoate by the OH radical

The file attached to this record is the author's final peer reviewed version.Atmospheric oxidation of methyl propanoate (MP) by the OH radical has been performed using density functional theory (BMK, BBIK) and ab initio (MP2, CBS-QB3) calculations. The thermodynamic and kinetic parameters are calculated. Three channels have been discussed. These reactions occur through low energy barriers of 3.2–4.3 kcal/mol. The energy barriers increase in the order α < μ < β at CBS–QB3. However, BMK shows slightly different order. Rate constants and branching ratios reveal that the H-abstraction from Cα is as the dominant reaction over the whole temperature range of 200–300 K, with a competition from Cβ channel at lower temperature. The BB1K data reproduce the available experimental rate constant

Comparative Study of Winding Configurations of a Five-Phase Flux-Switching PM Machine

This paper introduces a general method for determination of the most suitable winding configurations for five-phase flux-switching permanent magnet (FSPM) machines, associated with feasible stator/rotor-pole combinations. Consequently, the effect of winding configurations on the performance of a five-phase outer-rotor FSPM machine is thoroughly investigated, including non-overlapping concentrated windings (single-layer, double-layer, and multi-layer) as well as distributed winding. The electromagnetic characteristics in the low-speed region, the flux-weakening capability in the high-speed region, and the fault-tolerant capability under faulty situations are evaluated and compared in detail. This work shows that compared with the conventional single-layer or double-layer concentrated windings, the FSPM machine with multi-layer type winding exhibits lower torque ripple and losses. Meanwhile, the motor with distributed windings possesses higher torque density and larger inductance. Finally, a prototype is manufactured, and the analysis results are validated by experiments