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1.
Iwan Setiawan Ardyono Priyadi Hajime Miyauchi Mauridhi Hery Purnomo 《IEEJ Transactions on Electrical and Electronic Engineering》2015,10(6):674-682
This paper presents a novel control system design for the grid‐side converter of doubly fed induction generator wind power generation systems. The control method proposed in this work is a vector control based on adaptive B‐spline neural network by using a simple fixed‐gain stabilizing control topology. The adaptive control is designed both for inner current loops and an outer DC‐link voltage loop of the grid side converter control system. To guarantee the control stability, the weights updating rule for the B‐spline neural network is synthesized by utilizing Lyapunov's direct method. To verify the effectiveness of the proposed control system, extensive simulations are performed using MATLAB/Simulink. Based on the simulation results, it is concluded that the proposed controller has improved performance compared to an optimum proportional integral control system. It is also relatively robust against external disturbances and variations of the control parameters. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
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Lilioara Surdu Ovidiu Iordache Elena Manaila Gabriela Craciun Laurentia Alexandrescu 《纺织学会志》2013,104(11):1426-1433
This paper presents the improvement of the resistance to fungi of some cotton textile materials by treating in the manufacturing process with oxygen plasma and chitosan. Thus, after the weaving and preliminary finishing, the fabrics were cleaned in oxygen plasma atmosphere and after dyeing, have been treated with chitosan solution with concentrations of 1 or 5 g/l, in order to confer them antimicrobial properties. The antimicrobial tests were performed with two fungi: Candida albicans and Tricophyton interdigitale. The obtained antimicrobial effect was considerably higher compared to that of the raw fabrics. The colour resistance of dyed fabrics was not significantly influenced by applying the treatment-based chitosan. 相似文献
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The effectiveness of transmutation for long-lived fission products (LLFP) in light water reactors (LWR), i.e. both BWR and PWR, considering the large capture cross-section of FPs in thermal region was evaluated. Calculation results of iodine and technetium transmutation in BWR and PWR suggested an effective use of BWR as compared to PWR. To obtain transmutation fraction [TF] of 30 to 40%, the irradiation period needed for 99Tc transmutation was estimated as 10 to 15 years, and the period for 129I transmutation was estimated as 30 to 40 years, respectively. The evaluations bring a new concept of multi-recycle LLFP transmutation using LWRTR (LWR for transmutation). 相似文献
4.
Osvaldo J. Rojas Ridwan Setiawan Jie Bao Peter L. Lee 《American Institute of Chemical Engineers》2009,55(4):963-982
Most modern chemical plants are complex networks of multiple interconnected nonlinear process units, often with multiple recycle and by‐pass streams and energy integration. Interactions between process units often lead to plant‐wide operability problems (i.e., difficulties in process control). Plant‐wide operability analysis is often difficult due to the complexity and nonlinearity of the processes. This article provides a new framework of dynamic operability analysis for plant‐wide processes, based on the dissipativity of each process unit and the topology of the process network. Based on the concept of dissipative systems, this approach can deal with nonlinear processes directly. Developed from a network perspective, the proposed framework is also inherently scalable and thus can be applied to large process networks. © 2009 American Institute of Chemical Engineers AIChE J, 2009 相似文献
5.
PS Cooke DL Buchanan P Young T Setiawan J Brody KS Korach J Taylor DB Lubahn GR Cunha 《Canadian Metallurgical Quarterly》1997,94(12):6535-6540
Estradiol-17beta (E2) acts through the estrogen receptor (ER) to regulate uterine growth and functional differentiation. To determine whether E2 elicits epithelial mitogenesis through epithelial ER versus indirectly via ER-positive stromal cells, uteri from adult ER-deficient ER knockout (ko) mice and neonatal ER-positive wild-type (wt) BALB/c mice were used to produce the following tissue recombinants containing ER in epithelium (E) and/or stroma (S), or lacking ER altogether: wt-S + wt-E, wt-S + ko-E, ko-S + ko-E, and ko-S + wt-E. Tissue recombinants were grown for 4 weeks as subrenal capsule grafts in intact female nude mice, then the hosts were treated with either E2 or oil a week after ovariectomy. Epithelial labeling index and ER expression were determined by [3H]thymidine autoradiography and immunohistochemistry, respectively. In tissue recombinants containing wt-S (wt-S + wt-E, wt-S + ko-E), E2 induced a similar large increase in epithelial labeling index compared with oil-treated controls in both types of tissue recombinants despite the absence of epithelial ER in wt-S + ko-E tissue recombinants. This proliferative effect was blocked by an ER antagonist, indicating it was mediated through ER. In contrast, in tissue recombinants prepared with ko-S (ko-S + ko-E and ko-S + wt-E), epithelial labeling index was low and not stimulated by E2 despite epithelial ER expression in ko-S + wt-E grafts. In conclusion, these data demonstrate that epithelial ER is neither necessary nor sufficient for E2-induced uterine epithelial proliferation. Instead, E2 induction of epithelial proliferation appears to be a paracrine event mediated by ER-positive stroma. These data in the uterus and similar studies in the prostate suggest that epithelial mitogenesis in both estrogen and androgen target organs are stromally mediated events. 相似文献
6.
The actinides and fission products produced in nuclear fuels constitute an important part of the HLW. Therefore, methods for reducing the radiotoxicity of the MA and LLFP in HLW are presently under investigation. The purposes of this study are to evaluate the effectiveness of MA transmutation by taking advantage of neutron spectrum hardening due to void fraction along BWR axial direction; to understand the effectiveness of LLFP transmutation in BWR considering the large capture cross section of FP in thermal region; and to evaluate the macroscopic characteristics of longer residential period of LLFP target in the high burnup BWR core. Conceptual B/T BWR supposed in this study was reactor which the performance comparable to the current BWR. In MA transmutation case, the calculation was focused on varying the void fraction of 0 to 40% along the axial direction, which were directly associated to the lower and upper region of the BWR core. The performance of B/T BWR was evaluated in which four components of MA (237Np, 241Am, 243Am, and 244Cm) with fixed fraction were blended with UO2 in B/T fuel. While, for LLFP transmutation, the B/T BWR was assumed to have two homogeneous regions: {1} the region for UO2 driver fuel (99% of fuel weight), and {2} the region for LLFP (99Tc and 129I) target capsules (1% of fuel weight), in which metallic Tc rods and iodine in the form of CeI3 was contained in cylindrical target capsules. The evaluation functions are {1} fission-to-transmutation ratio, [F/T ratio]MA, and {2} transmutation fraction, TfLLFP. Results show that the hardening neutron spectrum due to increase of void fraction in B/T BWR would result a higher [F/T ratio] of MA transmutation performance. Np and Am would be effectively loaded in the upper region of the core, while Cm could be loaded in any region of the core. At the EOC of equal or more than 50 GWd/Mg(HM), technetium has a higher transmutation fraction compared to iodine. To obtain higher LLFP transmutation fraction, the residential time in the LLFP targets in the core, should be kept for long time, for instance about 10 to 30 years. For that purpose, it was proposed that the number of B/T BWR system for LLFP treatment corresponds to the residential time of the LLFP target, i.e. 10 to 30 units. 相似文献
7.
We have investigated effects of annealing of MgO buffer layer on structural quality of ZnO layers grown by plasma assisted molecular beam epitaxy on c-sapphire. ZnO layers were characterized by atomic force microscopy, high resolution X-ray diffraction (HRXRD) and cross sectional transmission electron microscopy (TEM). AFM images show that annealing of a low temperature (LT)-MgO buffer at high temperatures enhanced the surface migration of adatoms, leading to the formation of larger terraces and smoother surface morphology, as indicated by the reduction of rms values of roughness from 0.6 to 0.3 nm. HRXRD and TEM experiments reveal that the dislocation density of ZnO layers is reduced from 5.3×109 to 1.9×109 cm−2 by annealing a LT-MgO buffer. All of those features indicate the structural quality of ZnO layers was improved by annealing a LT-MgO buffer layer. 相似文献
8.
K Kamigiri T Tokunaga T Sugawara K Nagai M Shibazaki B Setiawan RM Rantiatmodjo M Morioka K Suzuki 《Canadian Metallurgical Quarterly》1997,50(7):556-561
Two new types of macrolide antibiotics, YM-32890 A and B, have been isolated from the fermentation broth of cytophaga sp. YL-02905S. In this paper, the taxonomy of the producing strain, fermentation, isolation, structure elucidation, and biological activity of the antibiotics are reported. YM-32890 A inhibits the growth of staphylococci including a macrolide-resistant strain, but shows no antimicrobial activity against other Gram-positive, Gram-negative bacteria and yeast. 相似文献
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10.
Takuma Suzuki Hang-Ju Ko Agus Setiawan Jung-Jin Kim Koh Saitoh Masami Terauchi Takafumi Yao 《Materials Science in Semiconductor Processing》2003,6(5-6):519-521
We report the successful growth of Ga-polar GaN epilayers on O-polar ZnO templates pre-deposited on c-sapphire. Prior to GaN growth, NH3 is exposed onto the ZnO template. The polarity of the GaN layers is confirmed by etching of the surface and by conversion beam electron diffraction (CBED), while the O-polar ZnO is confirmed by CBED. It is suggested that the NH3 pre-exposure helps form a Zn3N2 layer, which possesses inversion symmetry and inverts the crystal from anion polar to cation polar. 相似文献