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91.
In high‐level synthesis, scheduling is an important stage which assigns each operation appearing in a data flow graph to a specific control step, whose results influence the design quality directly. This paper describes a scheduling approach for pipelined datapaths. Since few previous approaches estimate the interconnection cost between register (register‐to‐register cost), our approach introduces a datapath model with interconnection between registers across buses, and minimizes the total hardware cost including the register‐to‐register cost by force‐directed scheduling. © 1999 Scripta Technica, Electr Eng Jpn, 128(3): 63–71, 1999 相似文献
92.
Approximately 20,000 ha of densely built-up areas still remain in Japan. However, the advance of improvements in these areas has been very slow. Thus, making draft improvement plans through citizen–administration partnerships is indispensable to promote improvements. The planning support tool proposed in this study supports a consensus-building process during the creation of draft improvement plans. We develop a disaster mitigation performance evaluation method (DMPEM) for built-up areas at the district level and incorporate this method into a disaster mitigation support Web-GIS. However, DMPEM requires lengthy calculation time because it uses the probabilistic Monte Carlo computation method. Using this tool in real- time planning is therefore difficult. In this study, we first develop a system that reduces the calculation time required by DMPEM. Second, the support tool is used to make draft plans through citizen–administration partnerships in districts where residents are conducting various disaster mitigation activities. Finally, we investigate the usefulness of the tool for consensus building through the promotion of lively discussions among residents and clarify the issues associated with practical use of the tool. 相似文献
93.
Tomohiko Yamanashi Tatsuya Hatori Yoshito Ishihara Norihisa Kawashima Katsumi Niwa 《Architectural Design》2011,81(6):100-107
Numbering 65, Nikken Sekkei's research group is the size of many substantial practices. Tomohiko Yamanashi, Tatsuya Hatori, Yoshito Ishihara and Norihisa Kawashima at Nikken Sekkei Ltd and Katsumi Niwa at the Nikken Sekkei Research Institute (NSRI) describe the unique collaborative processes that make the NSRI's contribution essential to any Nikken projects requiring the development of cutting-edge technology or urban planning proposals. Here, they detail the development of BIO SKIN, an innovative facade system developed for the Sony Research and Development Center in Tokyo, which addresses the urban heat island effect, one of the main environmental research areas of the NSRI. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
94.
Kondo A Noguchi H Ohnishi S Kajiro H Tohdoh A Hattori Y Xu WC Tanaka H Kanoh H Kaneko K 《Nano letters》2006,6(11):2581-2584
Crystal-to-crystal transformation from a 3D interpenetrated-type MOF {[Cu(BF(4))(2)(bpy)(H(2)O)(2)] (bpy)} (1) to a 2D square-grid-type [Cu(BF(4))(2)(bpy)(2)] (2) (bpy = 4,4'-bipyridine) was observed. It was derived from dehydration and confirmed by in situ FT-IR, TG, and elemental analysis. Moreover, we elucidate the novel expansion/shrinkage dynamic modulation of 2 triggered by clathrate formation with gas molecules. 相似文献
95.
Receptor internalization is a useful indicator of the activity of ligands. The N-terminus of the β(2)-adrenergic receptor expressed on the cell surface was labeled with fluorophores using a novel coiled-coil labeling system. Endocytosis of the receptors was automatically detected using a fluorescence image analyzer by evaluating (1) translocation of the receptor from cell-surface to intracellular regions and (2) acidification in endosomes. Both parameters increased upon agonist stimulation in a dose-dependent manner. The extent of endocytosis was significantly dependent on the agonist used, indicating the presence of a biased signaling for endocytosis. The receptor antagonists can also be screened by competitive inhibition of agonist-induced endocytosis. The image analysis approach has proven to be useful for high-throughput characterization and screening of GPCR ligands. 相似文献
96.
Gold nano-rod array membranes (Au-NRM) were prepared by modification of the template method. A simple two-electrode device was assembled by holding an electrolyte solution between the Au-NRM and a transparent electrode. Small reflectance changes (less than 2%) in the visible band were induced on the Au-NRM surface by applying a DC voltage to the device. These changes could be visually observed. It was found based on a further evaluation that the reflectance changes responded very fast (less than 100 ms) to the DC voltage application, and were stable during the switching repetition (over 5000 times). When the cyclic scanning of the applied voltage to the device was carried out between -1.5 V and +1.5 V, the reflectance changes were increased over +1.0 V (-1.0 V). It was suggested from these experimental results that the reflectance changes were attributed to the surface oxidation and the deformation or mechanical motion of the Au nano-rod. 相似文献
97.
Yuhao Jin Katsumi Yoshida Tadashi Maruyama 《Journal of Nuclear Science and Technology》2017,54(4):424-431
Specimens of two kinds of isotropic nuclear graphite, IG-110U and ETP-10, were neutron-irradiated at fluence of 1.92 × 1024 n/m2 (E > 1.0 MeV) at 473 K. The recoveries of the macroscopic lengths of these specimens during isothermal and isochronal annealing at temperatures of up to 1673 K were investigated in a step-wise manner by using a precision dilatometer. The macroscopic lengths after isochronal annealing for 6 h at each temperature decreased gradually as the temperature was increased to 1673 K. The recovery trends of the c-axis and a-axis lattice parameters differed from one another, and from the macroscopic length recovery trends. For the IG-110U specimen, the activation energies (Ea) of macroscopic volume recovery corresponding to annealing at 523–773, 773–923, 923–1073, and 1073–1173 K were found to be 0.15, 0.34, 0.73, and 2.59 eV, respectively. For the ETP-10 specimen, the Ea corresponding to 523–923, 923–1223, and 1223–1373 K were determined to be 0.15, 0.46, and 2.19 eV, respectively. These results indicate that both graphite specimens underwent three or four stages of macroscopic length recovery between 523 K and the annealing temperatures at which their initial lengths were recovered. It is suggested that during the first stage recovery proceeded via the migration of single interstitials along the basal plane and the resulting V-I recombination. In the middle stages, recovery occurred due to the migration of interstitial groups such as C2 along the basal plane, while in the last stage, it proceeded via through-layer migration of interstitials or migration of single vacancies. 相似文献
98.
Liufa Liu Katsumi Tanaka Akio Hirose Kojiro Kobayashi 《Science and Technology of Advanced Materials》2013,14(4):335-344
We investigated the effects of precipitation phases on the hydrogen embrittlement (HE) sensitivity of Inconel 718 by means of tensile tests. Hydrogen was charged into the test specimens via a cathodic charging process prior to the tensile tests. Various heat treatments were applied to conventionally aged specimens to fabricate specimens with different precipitation conditions for the γ″ phase and the δ phase. For each precipitation condition, we fabricated two specimens, one of which was charged with hydrogen before the tensile test. All specimens were tensioned under identical tensile conditions. The percent loss of the reduction of area (RA) caused by pre-charged hydrogen was used to assess HE sensitivity. Both the δ phase and the γ″ phase were found to play significant roles in altering HE sensitivity of Inconel 718. When these phases were totally dissolved, the HE sensitivity of the alloy was very low. The percent loss of RA decreased along with a decrease in the fractional volume of γ″. The δ-free aged alloy had greatly enhanced HE resistance, the same level as that of conventionally annealed alloy, and its strength was equal to that of the conventionally aged alloy. Fracture origins noted on the specimens were located on the surface layers and displayed brittle cleavage when pre-charged hydrogen was utilized. Local transgranular cleavages initiated from the δ/matrix were also observed in conventionally aged specimens, where there was a presence of pre-charged hydrogen. Therefore, the δ phase was considered to promote HE by initializing micro-cracks from δ/matrix interfaces. Since the d-free aged alloy has both good strength and good ductility, we propose that it is advantageous for fabricating some hydrogen-containing parts. 相似文献
99.
A gel‐spinning process was used in an attempt to prepare a gelatin fiber with a high level of drawability. A gel fiber prepared by extrusion of 15 wt % gelatin in dimethyl sulfoxide into methanol at ?20°C was drawn to sixteen times the original length. After extraction of the dispersion medium, the mechanical strength of the fiber increased markedly with the draw ratio, and the fiber exhibited a tensile strength of 146 MPa and a Young's modulus of 2.3 GPa when drawn to the maximum. A gelatin fiber with greater mechanical strength was obtained when ethylene glycol was used as the spinning solvent. The X‐ray diffraction profile indicated the formation of triple‐helical structures and their lateral association, which is responsible for the mechanical strength of the fiber. Heat‐treatment improved the water‐resistance of the prepared fiber. γ‐Irradiation and treatment with glutaraldehyde improved the mechanical strength of the fiber. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
100.
Hiroshi Yamaguchi Xin-Rong Zhang Katsumi Fujima 《International Journal of Refrigeration》2008,31(3):404-410
In this paper, a cryogenic refrigeration method is described, which utilizes CO2 solid–gas two phase flow and the dry ice. The CO2 solid–gas two phase flow is achieved by expanding liquid CO2 and thus refrigeration process less than CO2 triple point −56.6 °C can be available. The experimental work is divided into two parts and two experimental set-ups were designed, constructed and tested. The interest of the first experiment test is the feasibility of expanding liquid CO2 into CO2 solid–gas flow in a horizontal circular tube by expansion valve. The second experiment focuses on the feasibility of the refrigeration of liquid CO2 expanding into solid–gas two phase flows used in a prototype CO2 heat pump system. The results show that solid–gas two phase flows can be achieved by expanding liquid CO2 by expansion valve in a closed CO2 heat pump system loop and low temperature refrigeration below −56.6 °C is achieved in the experiments, which give greater possibility to create a cryogenic refrigeration process below −56.6 °C for food industries, bio-medical engineering, etc. 相似文献