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排序方式: 共有785条查询结果,搜索用时 15 毫秒
21.
Softsensors or virtual sensors are key technologies in industry because important variables such as product quality are not always measured on-line. In the present work, two-stage subspace identification (SSID) is proposed to develop highly accurate softsensors that can take into account the influence of unmeasured disturbances on estimated key variables explicitly. The proposed two-stage SSID method can estimate unmeasured disturbances without the assumptions that the conventional Kalman filtering technique must make. Therefore, it can outperform the Kalman filtering technique when innovations are not Gaussian white noises or the characteristics of disturbances do not stay constant with time. The superiority of the proposed method over the conventional methods is demonstrated through numerical examples and application to an industrial ethylene fractionator. 相似文献
22.
Hidetsugu Nanba Natsumi Anzen Manabu Okumura 《International Journal on Digital Libraries》2008,9(2):151-161
The need for academic researchers to retrieve patents and research papers is increasing, because applying for patents is now
considered an important research activity. However, retrieving patents using keywords is a laborious task for researchers,
because the terms used in patents for the purpose of enlarging the scope of the claims are generally more abstract than those
used in research papers. Therefore, we have constructed a framework that facilitates patent retrieval for researchers, and
have integrated research papers and patents by analysing the citation relationships between them. We obtained cited research
papers in patents using two steps: (1) detection of sentences containing bibliographic information, and (2) extraction of
bibliographic information from those sentences. To investigate the effectiveness of our method, we conducted two experiments.
In the experiment involving Step 1, we prepared 42,073 sentences, among which a human subject manually identified 1,476 sentences
containing citations of papers. For Step 2, we prepared 3,000 sentences, in which the titles, authors, and other bibliographic
information were manually identified. We obtained a precision of 91.6%, and a recall of 86.9% in Step 1, and a precision of
86.2% and a recall of 85.1% in Step 2. Finally, we constructed an information retrieval system that provided two methods of
retrieving research papers and patents. One method was retrieval by query, and another was from the citation relationships
between research papers and patents. 相似文献
23.
24.
Kenichi Noguchi Yukihisa Matsuda Manabu Oishi Takaki Masaki Sadao Nakayama Masahiro Mizushina 《Journal of the American Ceramic Society》1990,73(9):2667-2676
Tensile strength of Y2 O3 -stabilized ZrO2 polycrystals (Y-TZP) was measured by a newly developed tensile testing method with a rectangular bar. The tensile strength of Y-TZP was lower than that of the three-point bend strength, and the shape of the tensile strength distribution was quite different from that of the three-point bend strength distribution. It was difficult to predict the distribution curve of the tensile strength using the data of the three-point bend strength by one-modal Weibull distribution. The distribution of the tensile strength was analyzed by two- or three-model Weibull distribution coupled with an analysis of fracture origins. The distribution curve of the three-point bend strength which was estimated by multimodal Weibull distribution agreed favorably with that of the measured three-point bend strength values. A two-modal Weibull distribution function was formulated approximately from the distributions of the tensile and three-point bend strengths, and the estimated two-modal Weibull distribution function for the four-point bend strength agreed well with the measured four-point bend strength. 相似文献
25.
In this study, a three-point bendJ lc fracture-toughness test was carried out using four types of structural steels at room temperature. The values of (γ p)V, which represent the width of the region where the voids are located just ahead of the crack tip, were measured by Beacham's method [9] with the help of a scanning electron microscope (SEM). The experimental (γ p) values and the theoretical values obtained using the finite element method (FEM) or calculated fromK at initiation are in good agreement. It was found that there is a certain linear relationship between (γ p)Vand the stretched zone width (SZW), and an experimental relationship betweenJ lc andσ flow·(γ p)V which may be expressed by the following equation: $$J_{lc} = 44.1 + 0.35\sigma _{{\text{flow}}} \cdot (\gamma _{\text{p}} )V_c KJ$$ whereσ flow is the average value of the yield stress and the ultimate tensile strength. (γ p)V c represents the critical value of (γ p)V. The numerical constant 44.1 kJ m?2 is considered to be aJ lc value for brittle fracture of the material tested, according to the authors' previous results. It is possible to calculateJ lc if (γ p)V c can be measured. 相似文献
26.
Yukio Tachibana Shigeaki Nakagawa Takeshi Takeda Akio Saikusa Takayuki Furusawa Kuniyoshi Takamatsu Kazuhiro Sawa Tatsuo Iyoku 《Nuclear Engineering and Design》2003,224(2):1010-197
Safety demonstration tests using the High Temperature Engineering Test Reactor (HTTR) will be conducted for the purpose of demonstrating inherent safety features of High Temperature Gas-cooled Reactors (HTGRs) as well as providing the core and plant transient data for validation of HTGR safety analysis codes. The first phase safety demonstration test items include the reactivity insertion test and the coolant flow reduction test. In the reactivity insertion test, which is the control rod withdrawal test, one pair out of 16 pairs of control rods is withdrawn, simulating a reactivity insertion event. The coolant flow reduction test consists of the partial loss of coolant flow test and the gas circulators trip test. In the partial loss of coolant flow test, primary coolant flow rate is slightly reduced by control system. In the gas circulators trip test one and two out of three gas circulators are run down, simulating coolant flow reduction events. The gas circulators trip tests, in which position of control rods are kept unchanged, are simulation tests of anticipated transients without scram (ATWS). 相似文献
27.
Naoki Yuda Miyuki Tanaka Manabu Suzuki Yuzo Asano Hiroshi Ochi Keiji Iwatsuki 《Journal of food science》2012,77(12):H254-H261
Abstract: Polyphenols, retained in black tea wastes following the commercial production of tea beverages, represent an underutilized resource. The purpose of this study was to investigate the potential use of hot‐compressed water (HCW) for the extraction of pancreatic lipase‐inhibiting polyphenols from black tea residues. Black tea residues were treated with HCW at 10 °C intervals, from 100 to 200 °C. The resulting extracts were analyzed using high‐performance liquid chromatography‐mass spectrometry and assayed to determine their inhibitory effect on pancreatic lipase activity in vitro. Four theaflavins (TF), 5 catechins, 2 quercetin glycosides, quinic acid, gallic acid, and caffeine were identified. The total polyphenol content of extracts increased with increasing temperature but lipase inhibitors (TF, theaflavin 3‐O‐gallate, theaflavin 3′‐O‐gallate, theaflavin 3,3′‐O‐gallate, epigallocatechin gallate, and epicatechin gallate) decreased over 150 °C. All extracts inhibited pancreatic lipase but extracts obtained at 100 to 140 °C showed the greatest lipase inhibition (IC50s of 0.9 to 1.3 μg/mL), consistent with the optimal extraction of TFs and catechins except catechin by HCW between 130 and 150 °C. HCW can be used to extract pancreatic lipase‐inhibiting polyphenols from black tea waste. These extracts have potential uses, as dietary supplements and medications, for the prevention and treatment of obesity. Practical Application: Active forms of lipase inhibitors can be recovered from black tea residues. They could be used as dietary supplements or medications. 相似文献
28.
Hyeonseok Jee Sumin Im Manabu Kanematsu Hiroshi Suzuki Satoshi Morooka Koyama Taku Akihiko Machida Sungchul Bae 《Journal of the American Ceramic Society》2020,103(12):7188-7201
We examined the effect of incorporating high-volume fly ash on the atomic arrangement and interatomic deformation behavior of calcium silicate hydrates in tricalcium silicate paste upon exposure to external forces. The interatomic structural changes and strains under compressive load were assessed using synchrotron in situ high-energy X-ray scattering-based atomic pair distribution function analysis. Three different types of strains, which were (a) macroscopic strains from gauges on the surfaces of specimen, (b) strains in a reciprocal space (Bragg peak shift), and (c) strains in real space (PDF peak shift), were compared to each other. All monitored and calculated strains for tricalcium silicate-fly ash (50 wt% fly ash) paste were compared with the counterparts of the pure tricalcium silicate paste. Pair distribution function analysis in the range of r < 10 Å indicated that the atomic arrangement of tricalcium silicate-fly ash was similar to that of synthetic calcium silicate hydrates followed by that of pure tricalcium silicate paste. Moreover, the pair distribution function refinement results revealed that the calcium silicate hydrate structure in tricalcium silicate-fly ash paste was similar to tobermorite 11 Å, unlike that in pure tricalcium silicate paste. The interatomic strain of tricalcium silicate-fly ash in the real space (r < 20 Å) was smaller than that of tricalcium silicate under compression, which suggested that the incompressibility of calcium silicate hydrates at atomistic scale was enhanced by the incorporation of fly ash into it. This was likely to be caused by the increased silicate polymerization of calcium silicate hydrates, which was attributed to the increase in the amount of silicate in their structure via the addition of fly ash. 相似文献
29.
30.
Akihiro Shimamura Manabu Fukushima Mikinori Hotta Tatsuki Ohji Naoki Kondo 《Journal of the American Ceramic Society》2016,99(2):440-444
A novel fabrication route to make macroporous silicon carbide (SiC) has been proposed in this study. The route is composed of the following two steps: the fabrication of porous α‐SiC/novolac‐type phenolic composite using hexamethylenetetramine (HMT) as a curing/blowing agent for the novolac monomer and a conventional reaction‐bonded (RB) sintering of the composite. The α‐SiC/novolac‐type phenolic composite was carbonized at 800°C for 2 h in N2 gas and then reacted with the molten silicon at 1450°C for 30 min under vacuum, resulting in the macroporous RB‐SiC with an open porosity of 48% and relatively large pore size of ~110 μm. The compressive strength of the macroporous RB‐SiC was 113 MPa, which is relatively high compared to those reported for macroporous SiC of equivalent porosities and pore sizes. 相似文献