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排序方式: 共有610条查询结果,搜索用时 15 毫秒
291.
292.
Seiji Hashimoto Hiroyuki Okuda Yasushi Okada Shuichi Adachi Shinji Niwa Mitsunobu Kajitani 《Electrical Engineering in Japan》2009,169(3):47-55
Conservation of the environment has become critical to the automotive industry. Recently, requirements for on‐board diagnostic and engine control systems have been strictly enforced. In the present paper, in order to meet the requirements for low‐emission vehicles, a novel method for construction of the air‐fuel ratio (A/F) control system is proposed. The method of construction of the system is divided into two steps. The first step is to design the A/F control system for the engine based on an open loop design. The second step is to design the A/F control system for the catalyst system. The design method is based on generalized predictive control in order to assure robustness to open loop control as well as model uncertainty. The effectiveness of the proposed A/F control system is verified through experiments using full‐scale products. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 169(3): 47–55, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20907 相似文献
293.
Tetsuya Doi Takanobu Ogawa Jiro Kaku 《Journal of Wind Engineering & Industrial Aerodynamics》2010,98(1):55-61
An experimental facility was developed for investigating pressure waves generated by high-speed trains. The facility launches a 1/30 scale model conforming to the actual shape of the train and enables measurements to be carried out with the same geometric configurations at full scale. The train models are launched using compressed air. A mathematical model is developed to predict the performance of the experimental facility. This model allows the optimum values of the design parameters of the facility to be determined in order to achieve a given target velocity and to control the launching velocity by adjusting the pressure of the compressed air. Measurement of the flow in the experimental facility shows that the facility performs as designed by the mathematical model and is capable of launching a train model at velocities greater than 500 km/h. Pressure waves generated by a train moving into a tunnel are measured, and the experimental data agree well with field measurements. The effect of the train nose on the strength and form of the pressure waves is also discussed. 相似文献
294.
Synthesis, structure and properties of polyhydroxyalkanoates: biological polyesters 总被引:30,自引:0,他引:30
High molecular weight polyhydroxyalkanoates (PHA) are synthesized and stored in the cell cytoplasm as water-insoluble inclusions by various microorganisms. This intriguing biological polyester initially attracted the attention of microbiologists and managed to keep many polymer scientists occupied over the second half of the last century. Concerted multidisciplinary scientific approaches have been directed to the elucidation of various aspects of PHA. Of significant interest are the findings that PHA can consist of various hydroxyalkanoate monomers, and the cloning of its biosynthesis genes. This has resulted in the production of PHA with various physical properties by genetically engineered microorganisms. In fact, it is now possible that large-scale production of PHA by transgenic plants can be achieved in the near future. The physical properties of PHA homopolymers as well as co- and heteropolymers have been the subject of study in various laboratories all over the world. By controlling the monomer composition of PHA, polymer scientists have shown that the polymer's physical properties can be regulated to a great extent. Furthermore, it is also clear that the rate of degradation of PHA in various environments can be controlled by judiciously altering its monomer compositions. This review attempts to bring together the biochemical and physicochemical aspects of PHA along with new perspectives on its potential therapeutic applications. 相似文献
295.
An actively mode-locked laser (MLLD) integrated with a distributed Bragg reflector (DBR) was used as a light source for optical subcarrier transmission. The millimeter (mm)-wave power penalty due to fiber dispersion is suppressed within 4 dB by operating this laser in a symmetric four-mode configuration. The experimental results agree well with the calculation of dispersion-induced penalty for a four-component-lightwave source. Optical subcarrier transmission free from dispersion-induced penalty within experimental error is achieved by further suppression of the end-modes of the DBR-MLLD using a fiber Bragg grating (FBG) 相似文献
296.
Nanostructured Fe-Pd thin films with about 30 at.% Pd have been successfully synthesized on the substrates of Pt buffer layer/Cr seed layer/Si by an electrodeposition process from a plating bath containing ammonium tartrate, citric acid and ammonia solution as complexing agents. Results clearly show that the as-deposited films with body-centered cubic structure were transformed into face-centered cubic structure by heating at 900 °C for 45 min followed by quenching into iced water. The in situ X-ray diffraction analysis results indicate that the quenched film with 29.8 at.% Pd undergoes a reversible thermoelastic austenite-to-martensite transformation with a narrow temperature hysteresis and a martensite transformation temperature of about −30 °C. The present study demonstrates the effectiveness of electrodeposition for synthesizing nanostructured Fe-Pd thin films for the application of low-temperature-type thermoelastic shape memory alloys. 相似文献
297.
Hiroki Nagai Chihiro Mochizuki Hiroki Hara Ichiro Takano Mitsunobu Sato 《Solar Energy Materials & Solar Cells》2008,92(9):1136-1144
Fabrication of vis-responsive anatase thin films with enhanced UV-sensitivity was attained on an ITO pre-coated glass substrate by applying two precursor solutions involving Ti complexes of oxalic acid and EDTA. The transparent and crack-free thin films were characterized by XRD, XPS, UV–vis and FE-SEM observation. The highest sensitivity to UV light of the vis-responsive film, whose photocatalytic activity was measured by the decomposition rate of methylene blue, was four times as compared with that formed by a sol–gel method under the same conditions. The vis-responsive films showed a characteristic absorption band at around 480 nm. 相似文献
298.
The genes encoding the envelope glycoprotein H (gH) and gB homologues were identified by sequencing genomic clones of human herpesvirus-7 (HHV-7), strain JI. A gB cDNA clone from HHV-7 strain AL was also identified. The deduced primary translation products of the gH and gB genes are a protein of 690 amino acids, with a predicted mass of 80.4 kD, and a protein of 822 amino acids, with a predicted mass of 93.3 kD, respectively. Both the predicted proteins have the characteristics of transmembrane glycoproteins, containing signal and transmembrane sequence motifs and characterized by the presence of 10 (gH) and 11 (gB) potential motifs for N-glycosylation. Comparison of amino acid sequence of HHV-7 gH and gB with the homologous sequences of the other human herpesviruses reveals closest homology with HHV-6 (38.8% identity for gH, 56.2% identity for the gB). In addition, significant sequence similarity was also observed between the gH and gB of HHV-7 and the homologs encoded by human cytomegalovirus (21.6% identity for gH, 37.6% identity for gB). No significant differences existed between the gB sequence of the two different HHV-7 strains analyzed. The products of the HHV-7 gH and gB expressed transiently in eukaryotic cells were specifically recognized by an HHV-7-reactive human serum in immunofluorescence assays. 相似文献
299.
In the rat platelet factor 4 (PF4) promoter, Ets motifs and GATA motifs are located at positions -880, -75 and -135, -30, respectively, and their motifs are found in the promoter region of most megakaryocyte protein genes. In order to investigate how the Ets and GATA motifs affect PF4 promoter activity, we constructed Ets and/or GATA motif mutant genes. A single disruption of either -75Ets, -135GATA, or -30GATA significantly reduced PF4 promoter activity, and double disruptions involving these motifs completely abolished it. Furthermore, gel-retardation assays revealed that Ets-1 and GATA-1 proteins from HEL and MEG-01 cells bound to the Ets motifs and GATA motifs, respectively. Co-transfection experiments showed that the overexpression of Ets-1 and/or GATA-1 enhanced the expression of the PF4 promoter reporter gene. These effects of Ets-1 and GATA-1 on PF4 promoter activity are additive. When HEL cells were treated with dimethylsulfoxide in order to induce differentiation into megakaryocytes, the mRNA level of ets-1 increased 10-fold, which might be directly correlated with the significant increase in PF4 mRNA level induced by dimethylsulfoxide. All these results strongly suggest that both Ets-1 and GATA-1 play key roles in the positive regulation of PF4 gene expression. 相似文献
300.
M Aoshima M Doi Y Usui H Tada N Chonabayashi M Matsusako H Watanabe O Doi T Uekusa S Saiki 《Canadian Metallurgical Quarterly》1998,36(11):978-983
We encountered a 23-year-old woman with allergic granulomatous angiitis (AGA) associated with cerebral infarction, myo-pericarditis, and acute respiratory failure due to extended eosinophilic pneumonia. She underwent emergency treatment at our hospital because of right hemiparesis and impaired consciousness. AGA was suspected because the patient had a history of bronchial asthma accompanied by pulmonary infiltrations with eosinophilia, and presented with diffuse pulmonary infiltrates, pericardial effusion, diffuse hypokinesis of myocardium, cerebral infarction and marked peripheral eosinophlia. Pulmonary eosinophilia was confirmed by examination of broncho-alveolar lavage fluid. Myocardial tissue biopsy specimens revealed fibrous granulation indicative of myocarditis. The patient responded well to corticosteroid therapy. 相似文献