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排序方式: 共有636条查询结果,搜索用时 237 毫秒
131.
Junichi Karasawa Yasuaki Hamada Koji Ohashi Eiji Natori Koichi Oguchi Tatsuya Shimoda 《Integrated ferroelectrics》2013,141(1):193-202
In order to reduce the thermal budget for SBT crystallization process in planer type stack cell FeRAMs, Rapid Thermal Anneal (RTA) based process for SBT thin film was investigated. Our new process is characterized by crystallization in RTA without any furnace annealing process, and includes a low temperature recovery annealing process (hereafter RTB (Reduced Thermal Budget) process). As a result of only 750C RTA for accumulated time of 60s without furnace annealing process, the sufficient ferroelectric properties were derived in comparison with that of conventional SBT thin film. In the RTB process, two approaches to improve the break down voltage were carried out. First, we used UV exposure during the baking process. By optimizing the UV assisted baking process, a high break down field due to smooth surface morphology was successfully obtained, resulting in break down field of more than 1.2 MV/cm. Secondly, ultra thin SBT films as a top few layer on the base SBT thin film were employed. After optimization of the ultra thin SBT layer thickness, a very smooth SBT surface was successfully achieved, resulting in improvement of the break down field of more than 1.1 MV/cm. 相似文献
132.
Yoshio Maruyama Yoichiro Iwase Kazuo Koga Junichi Yagi Hiroo Takada Naohisa Sunaga Shigeomi Nishigaki Takashi Ito Kinya Tamaki 《Automation in Construction》2000,9(5-6):503-514
In this study, we proposed a concept of virtual and real-field construction management systems (VR-Coms), which is integrated with virtual construction simulation, planning, scheduling, and performance management systems to evaluate productivity and safety in virtual simulated and real-field constructions. And, we built up a computational environment to develop the VR-Coms. The VR-Coms offer supporting modules for learning and discovering solutions with objective to manage construction at right speed with improved humanware and constructability. The configuration of VR-Coms is described. This paper also shows an application of agent theory to construction management. 相似文献
133.
Takaaki Noda Doohwan Lee Hyunyoung Shim Masao Sakuraba Takashi Matsuura Junichi Murota 《Thin solid films》2000,380(1-2):57-60
Doping and electrical characteristics of in-situ heavily B-doped Si1−x−yGexCy (0.22<x<0.6, 0<y<0.02) films epitaxially grown on Si(100) were investigated. The epitaxial growth was carried out at 550°C in a SiH4–GeH4–CH3SiH3–B2H6–H2 gas mixture using an ultraclean hot-wall low-pressure chemical vapor deposition (LPCVD) system. It was found that the deposition rate increased with increasing GeH4 partial pressure, and only at high GeH4 partial pressure did it decrease with increasing B2H6 as well as CH3SiH3 partial pressures. With the B2H6 addition, the Ge and C fractions scarcely changed and the B concentration (CB) increased proportionally. The C fraction increased proportionally with increasing CH3SiH3 partial pressures. These results can be explained by the modified Langmuir-type adsorption and reaction scheme. In B-doped Si1−x−yGexCy with y=0.0054 or below, the carrier concentration was nearly equal to CB up to approximately 2×1020 cm−3 and was saturated at approximately 5×1020 cm−3, regardless of the Ge fraction. The B-doped Si1−x−yGexCy with high Ge and C fractions contained some electrically inactive B even at the lower CB region. Resistivity measurements show that the existence of C in the film enhances alloy scattering. The discrepancy between the observed lattice constant and the calculated value at the higher Ge and C fraction suggests that the B and C atoms exist at the interstitial site more preferentially. 相似文献
134.
Toru Izaki Toshimi Kobayashi Junichi Kusumoto Akihiro Kanaya 《International Journal of Pressure Vessels and Piping》2009
The small punch creep (SPC) test is considered as a highly useful method for creep life assessment for high temperature plant components. SPC uses miniature-sized specimens and does not cause any serious sampling damages, and its assessment accuracy is at a high level. However, in applying the SPC test to the residual creep life assessment of the boiler in service, there are some issues to be studied. In order to apply SPC test to the residual creep life assessment of the 2.25Cr–1Mo steel boiler pipe, the relationship between uniaxial creep stress and the SPC test load has been studied. 相似文献
135.
Recently,a number of environmental problems caused from fossil fuel combustion have been focused on.Inaddition,with the eventual depletion of fossil energy resources,hydrogen gas is expected to be an alternativeenergy resource in the near future.It is characterized by high energy per unit weight,high reaction rate,widerange of flammability and the low emission property.On the other hand,many researches have been underway inseveral countries to improve a propulsion system for an advanced aircraft.The system is required to have higherpower,lighter weight and lower emissions than existing ones.In such a future propulsion system,hydrogen gaswould be one of the promising fuels for realizing the requirements.Considering these backgrounds,our group hasproposed a new cycle concept for hydrogen-fueled aircraft propulsion system.In the present study,we perform 3dimensional computations of turbulent flow fields with hydrogen-fueled combustion around a turbine blade.Themain objective is to clarify the influence of arrangement of hydrogen injector holes.Changing the chordwise andspanwise spacings of the holes,the 3 dimensional nature of the flow and thermal fields is numerically studied. 相似文献
136.
H Morikawa K Fukuda H Mima T Shoda S Kato K Mori 《Canadian Metallurgical Quarterly》1998,351(2):247-252
We focus here upon regulation by the notochord of myocardial cell fate in zebrafish. Myocardial precursors, defined by lineage tracing in the living embryo, are in the lateral plate mesoderm adjacent to the notochord-prechordal plate junction. Interestingly, the anterior end of the notochord corresponds to the posterior extent of the heart progenitor field, defined by this lineage analysis. This suggested that the notochord might suppress, or the prechordal plate might enhance, the cardiogenic fate. Nkx2.5 expression is, in the zebrafish embryo, closely correlated with the position of myocardial precursors, which reside adjacent to the notochord-prechordal plate junction. This expression, however, is extinguished in the region posterior to this junction, a region normally not contributing cells to the heart. Laser ablation of the notochord tip between the 4-somite and 12-somite stage causes posterior expansion of the Nkx2. 5-expressing region. The ntl mutation of the notochord is associated with posterior extension of Nkx2.5 expression. Lineage tracking, by laser activation of caged fluoresceinated dextran, confirms that, normally, lateral plate cells next to the notochord do not contribute progeny to the heart. After anterior notochord ablation, these cells are redirected to a heart cell fate. These data suggest that the anterior notochord delimits the posterior extent of the heart field by suppressing the heart cell fate. 相似文献
137.
138.
Nano-abrasion machining of brittle materials and its application to corrective figuring 总被引:1,自引:0,他引:1
Osamu Horiuchi Junichi Ikeno Hideo Shibutani Hirofumi Suzuki Yoshiaki Mizukami 《Precision Engineering》2007,31(1):47-54
A method of ultraprecision abrasion machining named “Nano-abrasion machining” is proposed for optical finishing of brittle materials. The fundamental characteristics and its applicability for corrective figuring to improve form accuracy of optics of brittle materials are investigated. It is experimentally ascertained that the material removal rate and surface roughness are suitable for optical finishing. However, the cross-sectional profile of the machined spot that is dependent on the collision angle is a combination of V- and W-shape, which is unsuitable for the corrective figuring. Therefore, circular motion machining is introduced and a preferable profile with an axis-symmetric V-shape is realized. The machining method is applied to corrective figuring of optical glass of BK7. The NC program is generated with a computer program developed by modifying the scanning motion and the form accuracy is predicted. According to the simulation results, corrective figuring is performed. The flatness is improved from PV = 151 to 29 nm. From the experimental results, it is clarified that the nano-abrasion machining is applicable to corrective figuring of brittle materials. 相似文献
139.
Kenichi Okazaki Yukinori Shima Daisuke Kurosaki Hiroyuki Miyake Junichi Koezuka Susumu Kawashima Masataka Shiokawa Hideaki Shishido Shunpei Yamazaki 《Journal of the Society for Information Display》2015,23(12):561-569
A 13.3‐inch 8k4k organic light‐emitting diode display based on a newly developed high‐mobility indium–gallium–zinc–oxide material was fabricated. It was found that the use of a higher‐mobility material decreases the scan driver size and power consumption. Furthermore, such oxide semiconductor layers with a buried channel structure can increase process stability and reliability. 相似文献
140.
Junichi KAKO 《控制理论与应用(英文版)》2019,17(2):138-147
Starting the engine and quickly adjusting the engine speed to the target value after that will always be a challenge for vehicles with an internal combustion engines at development sites in the automotive industry. The SICE Research Committee on Advanced Powertrain Control Theory provided this task as a benchmark problem with the engine model. Just as control developers in the industry are provided actual engines, many of the academic experts have acquired engine models, analyzed behavior and constructed controls, and solved control tasks. We summarize this activity by explaining the methods by many challengers that achieved the target performance. 相似文献