Optimization, 3D-Numerical Validations and Preliminary Experimental Tests of a Wound Rotor Synchronous Machine

In this paper, a complete methodology to design a modular brushless wound rotor synchronous machine is proposed. From a schedule of conditions and a chosen structure (with 7 phases, 7 slots and 6 poles), a non-linear and non-convex optimization problem is defined and solved using NOMAD (a derivative free local optimization code): the external volume is minimized under some constraints, which are the average torque equal to 5 Nm, the torque ripple less than 5%, the efficiency greater than 94%, and the surface temperature less than 85 °C. The constraints have to be computed using 2D-finite element simulations in order to reduce the CPU-time consumption for each NOMAD iteration. Moreover, a relaxation of this optimization problem makes it possible to provide an efficient starting point for NOMAD. Thus, a good optimal design is obtained, and it is then validated by using 3D electromagnetic and thermic numerical methods. These numerical verifications show that, inside the end-winding, the leakage flux is high. This yields a lot of iron losses in this machine. Moreover, the surface and coil temperature differences between the 2D and 3D numerical approaches are discussed. Finally, the machine prototype is built following the optimal dimensions and a POKI-POKITM assembly technology. Preliminary experimental tests are carried out, and the results are devoted to the comparison of measured and predicted 3D numerical results.

Daya Terima Konsumen Dan Sifat Fisik Roti Soft Roll Substitusi Tepung Hanjeli (C. Lacryma-jobi L.)

ABSTRACT The aim of this research was to analyze the effect of job’s tear flour substitution in bread making on the consumer’s acceptance based on external (volume, crust’s color, form’s symmetry, bake’s evenness, crust characteristic) internal (grain, crumb’s color, aroma, flavor, texture) characteristics and physical characteristics (volume, growth power ratio). This research used experimental method. The sample of this research was soft roll with job’s tear substitution 10%, 20%, and 30% amount of percentages. Data collection technique used was acceptance test hedonic scale by 25 unskill panelists. The result of hedonic test indicated that soft roll with 10% job’s tear flour substitution was the most preferred on internal characteristics and soft roll with 20% job’s tear flour substitution was the most preferred on external characteristics. Friedman test with significant level α=0.05 showed that job’s tear flour substitution had effects on volume, crust’s color, crust characteristic, grain, aroma, flavor, and texture on soft roll. Tuckey’s test result showed that job’s tear flour substitution as much 10% was the most preferred and was recommended to be developed. Physical characteristics valuation showed that soft roll with 10% job’s tear flour substitution had bigger volume and growth power ratio than the other samples. ABSTRAKPenelitian ini dilakukan untuk mengetahui pengaruh substitusi tepung hanjeli dalam pembuatan roti soft roll terhadap daya terima konsumen pada aspek eksternal (volume, warna kulit roti, bentuk, keseragaman pemanggangan, karakter kulit roti) aspek internal (pori-pori roti, warna crumb, aroma, rasa, tekstur) dan sifat fisik roti (volume roti, rasio pengembangan). Penelitian ini menggunakan metode ekperimen. Sampel dalam penelitian ini adalah roti soft roll substitusi tepung hanjeli dengan persentase 10%, 20%, dan 30%. Teknik pengumpulan data yang digunakan adalah tes kesukaan oleh 25 panelis tidak terlatih. Hasil tes kesukaan menunjukan roti soft roll substitusi tepung hanjeli 10% merupakan produk yang paling disukai pada aspek internal dengan rentan nilai 4,00 hingga 4,24 dan roti soft roll substitusi tepung hanjeli 20% merupakan produk yang paling disukai pada hampir semua aspek eksternal dengan rentan nilai 4,24 hingga 4,40. Berdasarkan hasil uji Friedman dengan perbedaan signifikan α=0,05 menyatakan terdapat pengaruh substitusi tepung pada aspek volume, warna kulit roti, karakter kulit roti, pori-pori roti, aroma, rasa hanjeli, dan tekstur. Hasil uji Tuckey menunjukan bahwa roti soft roll substitusi tepung hanjeli 10% adalah yang disukai konsumen, sehingga direkomendasikan untuk dikembangkan. Penilaian fisik menunjukkan roti soft roll substitusi tepung hanjeli 10% memiliki volume dan rasio pengembangan terbesar dibandingkan sampel lainnya.

Different Principles Govern Different Scales of Brain Folding

The signature folds of the human brain are formed through a complex and developmentally regulated process. In vitro and in silico models of this process demonstrate a random pattern of sulci and gyri, unlike the highly ordered and conserved structure seen in the human cortex. Here, we account for the large-scale pattern of cortical folding by combining advanced fetal magnetic resonance imaging with nonlinear diffeomorphic registration and volumetric analysis. Our analysis demonstrates that in utero brain growth follows a logistic curve, in the absence of an external volume constraint. The Sylvian fissure forms from interlobar folding, where separate lobes overgrow and close an existing subarachnoid space. In contrast, other large sulci, which are the ones represented in existing models, fold through an invagination of a flat surface, a mechanistically different process. Cortical folding is driven by multiple spatially and temporally different mechanisms; therefore regionally distinct biological process may be responsible for the global geometry of the adult brain.