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101.
Multi-objective optimization based on meta-modeling by using support vector regression 总被引:2,自引:0,他引:2
Practical engineering design problems have a black-box objective function whose forms are not explicitly known in terms of
design variables. In those problems, it is very important to make the number of function evaluations as few as possible in
finding an optimal solution. So, in this paper, we propose a multi-objective optimization method based on meta-modeling predicting
a form of each objective function by using support vector regression. In addition, we discuss a way how to select additional
experimental data for sequentially revising a form of objective function. Finally, we illustrate the effectiveness of the
proposed method through some numerical examples. 相似文献
102.
The thermo-emf ΔV and temperature difference ΔT across the boundary were measured as functions of r and I for the touching p- and n-type Cu/Bi–Te/Cu composites composed of t
Bi–Te = 2.0 mm and t
Cu = 0.3 mm, where r is the distance from the boundary and I is a direct current producing ΔT which flows through two Peltier modules connected in series. The resultant Seebeck coefficient α across the boundary is obtained
from the relation α = ΔV/ΔT. As a result, the resultant |α| of the touching p- and n-type composites have a great local maximum value at r ≈ 0.03 mm and decrease rapidly with further increase of r to approach the intrinsic |αBi–Te|. The maximum resultant α of the p- and n-type composites reached great values of 1,043 and −1,187 μV/K at 303 K corresponding
to I = 0.8 A and of 1,477 and −725 μV/K at 360 K corresponding to I = 2.0 A. Reflecting the temperature dependence of the intrinsic αBi–Te, the maximum α of the p-type composite increases with an increase of T, while that of the n-type one decrease with an increase of T. Surprisingly, the maximum α of the p- and n-type composites have great gradients of 8.36 and −7.15 μV/K2 in the range from 303 to 366 K, respectively, which are 21.8 and 134 times larger in absolute value than 0.383 and −0.0535 μV/K2 of the intrinsic p- and n-type αBi–Te, so that the maximum resultant α was thus found to be much more sensitive to temperature than the intrinsic αBi–Te. Moreover, the local Seebeck coefficient α
l
(r) derived analytically from the resultant α(r) is enhanced significantly in the narrow region below r ≈ 0.05 mm and the maximum α
l
values of the p- and n-type composites were found to have extremely great values of approximately 1,800 μV/K at 360 K and
−1,400 μV/K at 303 K, respectively, which are approximately 7.3 and 6.5 times higher in absolute value than the intrinsic
p- and n-type αBi–Te at the corresponding temperatures. 相似文献
103.
Hirotaka Sato Takashi KamiyamaKenji Iwase Toru IshigakiYoshiaki Kiyanagi 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,651(1):216-220
A time-of-flight (TOF) spectroscopic neutron imaging at a pulsed neutron source is expected to be a new material analysis tool because this method can non-destructively investigate the spatial dependence of the crystallographic and metallographic information in a bulk material. For quantitative evaluation of such information, a spectral analysis code for the transmission data is necessary. Therefore, we have developed a Rietveld-like analysis code, RITS. Furthermore, we have applied the RITS code to evaluation of the position dependence of the crystal orientation anisotropy, the preferred orientation and the crystallite size of a welded α-iron plate, and we successfully obtained the information on the texture and the microstructure. However, the reliability of the values given by the RITS code has not been evaluated yet in detail. For this reason, we compared the parameters provided by the RITS code with the parameters obtained by the neutron TOF powder diffractometry and its Rietveld analysis. Both the RITS code and the Rietveld analysis software indicated values close to each other, but there were systematic differences on the preferred orientation and the crystallite size. 相似文献
104.
Matsumoto Risa Ishikawa Toshiyuki Takemura Manabu Hiratsuka Yoshisato Kawano Hirotaka 《钢结构国际杂志》2016,16(4):1319-1327
International Journal of Steel Structures - Carbon fiber reinforced plastic, CFRP, plates bonding method is one of the new repair methods for fatigue cracks. In this method, propagation of fatigue... 相似文献
105.
Anusron Chueasamat Toshikazu Hori Hirotaka Saito Tomotaka Sato Yuji Kohgo 《Soils and Foundations》2018,58(2):290-305
In order to mitigate the damage due to sediment disasters, knowledge about how slopes fail due to rainfall is indispensable. The main objectives of this paper were to investigate experimentally the effects of surface sand layer density and rainfall intensity on the slop failures due to rainfalls. We conducted a series of experimental tests using 1g physical slope models constructed of Kasumigaura sand and a silt soil named DL clay for the permeable residual surface layer and the firm rock foundation, respectively. A total of nine cases with different combinations of surface sand layer densities and rainfall intensities was tested. Two types of failure: surface slide failure and retrogressive failure, were observed depending on the rainfall intensity and the surface sand layer density. The following mechanism of failure was accounted. At first some sands, which contained a lot of accumulated rainwater, flowed out (flowslide) at the slope toes. The flow slides may be due to the reductions of effective stresses as a result. When a surface slide failure occurred, most of the PWP (pore water pressure) values were still negative but the whole sand layers were almost at the saturation condition. In the case of retrogressive failures, seepage surfaces rose up to higher positions and excess PWPs appeared under the seepage surfaces. This difference of generation mechanism of PWP values may be the deciding factor in the difference in the type of failure. 相似文献
106.
Akinori Kashimura Masahiro Kimura Kazuaki Okawa Hirotaka Suzuki Atsushi Ukita Satoshi Wakita Kana Okazaki Misa Ohno Peter O. Bauer Masayoshi Sakaguchi Yasusato Sugahara Fumitaka Oyama 《International journal of molecular sciences》2015,16(2):4028-4042
Mouse acidic mammalian chitinase (AMCase) plays important physiological roles in defense and nutrition. AMCase is composed of an N-terminal catalytic domain (CatD) and a C-terminal chitin-binding domain (CBD). We expressed CatD of mouse AMCase as a recombinant fusion protein with Protein A and V5-His in Escherichia coli (Protein A-CatD-V5-His), evaluated its functional properties and compared them to the full-length AMCase (Protein A-AMCase-V5-His). Under our experimental conditions, the chitinolytic activity of both proteins against 4-nitrophenyl N,N''-diacetyl-β-d-chitobioside was equivalent with regard to their specific enzymatic activities, optimal pH and temperature as well as to the pH and temperature stability. CatD bound to chitin beads and cleaved the N-acetylglucosamine hexamer, colloidal and crystalline chitin as well as the shrimp shell, and released primarily N,N''-diacetylchitobiose fragments at pH 2.0. These results indicate that the primary structure of CatD is sufficient to form a proper tertiary structure required for chitinolytic activity, recognize chitin substrates and degrade them in the absence of a CBD. Our recombinant proteins can be used for further studies evaluating pathophysiological roles of AMCase in different diseases. 相似文献
107.
(Bi4.5+xNa0.5−x)(Ti2xNb2−2x)WO15 (BNTNW) compounds were synthesized and their ferroelectric properties were characterized. The X-ray powder diffraction patterns of the compounds revealed that they have a single phase over the whole composition range. The linear variations of the lattice parameters with composition indicate the formation of solid solutions, resulting in a reduction in the orthorhombicity of the compounds. The remnant polarization of the BNTNW decreased from 8.5 to 5.1 μC/cm2 with increasing x, which may be related to the orthorhombicity of the compounds. By using hot forging, an oriented BNTNW compound at x = 0 was obtained. Strong reflections from (0 0 l) were observed for sample // in which the measurement direction is parallel and the orientation factor of such sample was approximately 0.72. A remarkable increase in the remnant polarization (Pr) of the compound was observed for the sample ⊥ in which the direction of applied pressure is perpendicular to the measurement direction; the highest Pr value was 18 μC/cm2. 相似文献
108.
Toshihiro Sakurai Takahiro Hayasaka Hirotaka Sekiguchi Hiroshi Satoh Zhen Chen Hitoshi Chiba Shu-Ping Hui 《Journal of the science of food and agriculture》2019,99(4):1675-1681
The cover image is based on the Research Article Dietary salmon milt extracts attenuate hepatosteatosis and liver dysfunction in diet-induced fatty liver model by Toshihiro Sakurai et al., DOI: 10.1002/jsfa.9352
109.
110.
Daisuke Ikeda SungGi Chi Satoshi Uchiyama Hirotaka Nakamura Yong-Mei Guo Nobuhiko Yamauchi Junichiro Yuda Yosuke Minami 《International journal of molecular sciences》2022,23(11)
The European LeukemiaNet (ELN) criteria define the adverse genetic factors of acute myeloid leukemia (AML). AML with adverse genetic factors uniformly shows resistance to standard chemotherapy and is associated with poor prognosis. Here, we focus on the biological background and real-world etiology of these adverse genetic factors and then describe a strategy to overcome the clinical disadvantages in terms of targeting pivotal molecular mechanisms. Different adverse genetic factors often rely on common pathways. KMT2A rearrangement, DEK-NUP214 fusion, and NPM1 mutation are associated with the upregulation of HOX genes. The dominant tyrosine kinase activity of the mutant FLT3 or BCR-ABL1 fusion proteins is transduced by the AKT-mTOR, MAPK-ERK, and STAT5 pathways. Concurrent mutations of ASXL1 and RUNX1 are associated with activated AKT. Both TP53 mutation and mis-expressed MECOM are related to impaired apoptosis. Clinical data suggest that adverse genetic factors can be found in at least one in eight AML patients and appear to accumulate in relapsed/refractory cases. TP53 mutation is associated with particularly poor prognosis. Molecular-targeted therapies focusing on specific genomic abnormalities, such as FLT3, KMT2A, and TP53, have been developed and have demonstrated promising results. 相似文献