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941.
Takao Shibusawa 《Coloration Technology》1988,104(1):28-33
The relationship between the rate constants in empirical rate of dyeing equations and the diffusion coefficient of dye in the fibre have been clarified by means of a statistical curve fitting method, where the rate of dyeing curves calculated from the theoretical equations (those of Wilson and Newman) have been compared with those from the empirical equations in the range Mt/M∞ from zero to about 0.8. The comparisons revealed that many of the empirical equations are suitable for describing the dyeing rate when there is a delay of dye sorption in the early stages, and one of them is useful for determining the dyeing rate when there is rapid dye sorption at the initial stages. The fact that these empirical equations fit well to practical dyeing can be explained in terms of the sorption delay caused by the stagnant solution layer surrounding the fibres. 相似文献
942.
Vodhanel R.S. Elrefaie A.F. Wagner R.E. Iqbal M.Z. Gimlett J.L. Tsuji S. 《Lightwave Technology, Journal of》1989,7(10):1454-1460
The frequency modulation (FM) and amplitude modulation (AM) responses of a 1.5-μm distributed feedback (DFB) laser were measured to 15 GHz. At 9-mW output power, the magnitude of the FM response was flat out to 12 GHz, and there was a 15-25-ps delay between the FM and AM responses. Computer simulation techniques indicate that the measured FM response is adequate to produce good eye patterns for frequency-shift-keying modulation at data rates up to 20 Gb/s. The high-speed frequency-shift-keying modulation capability of this 1.5-μm DFB laser was experimentally confirmed at 11 Gb/s 相似文献
943.
944.
Koyama T Takano H Konishi S Tsuji T Takenaka H Ichimaru S Ohchi T Kagoshima Y 《The Review of scientific instruments》2012,83(1):013705
A circular multilayer zone plate (MZP) was fabricated and its focusing performance was evaluated using 20-keV x-rays. MoSi(2) and Si layers were alternately deposited by DC magnetron sputtering on a wire core; all the interfaces satisfied the Fresnel zone condition. The measured line spread function was converted to a point spread function by tomographic reconstruction. The results suggest that the MZP has the potential to realize the diffraction-limited resolving power, which is calculated to be 35 nm using the diffraction integral. Furthermore, scanning transmission microscopy using the MZP could resolve a 50-nm line-and-space pattern. 相似文献
945.
Effects of additives on sintering and some properties of calcium phosphates with various Ca/P ratios
Takafumi Kanazawa Takao Umegaki Kimihiro Yamashita Hideki Monma Tatsushi Hiramatsu 《Journal of Materials Science》1991,26(2):417-422
The effects were studied of additives on the sintering and properties such as the compressive strength and chemical durability of ceramics of calcium pyrophosphate, tricalcium phosphate and hydroxyapatite. In improving the compressive strength of these calcium phosphates, the effect of additives was found to be in the order Na2OCaF2>MgOgAl2O3, SiO2 for the case of single-doping, and was most marked in the combination of Na2O-MgO-Al2O3 for the complex addition. It was also found that the chemical durability of the calcium phosphates was improved greatly by using a single or complex additives. 相似文献
946.
This paper proposes an adaptive agent model with a hybrid routing selection strategy for studying the road-network congestion problem. We focus on improving those severely congested links. Firstly, a multi-agent system is built, where each agent stands for a vehicle, and it makes its routing selection by considering the shortest path and the minimum congested degree of the target link simultaneously. The agent-based model captures the nonlinear feedback between vehicle routing behaviors and road-network congestion status. Secondly, a hybrid routing selection strategy is provided, which guides the vehicle routes adapting to the real-time road-network congestion status. On this basis, we execute simulation experiments and compare the simulation results of network congestion distribution, by Floyd agent with shortest path strategy and our proposed adaptive agent with hybrid strategy. The simulation results show that our proposed model has reduced the congestion degree of those seriously congested links of road-network. Finally, we execute our model on a real road map. The results finds that those seriously congested roads have some common features such as located at the road junction or near the unique road connecting two areas. And, the results also show an effectiveness of our model on reduction of those seriously congested links in this actual road network. Such a bottom-up congestion control approach with a hybrid congestion optimization perspective will have its significance for actual traffic congestion control. 相似文献
947.
Yasuto Nakanishi Takayuki Tsuji Minoru Ohyama Katsuya Hakozaki 《Personal and Ubiquitous Computing》2000,4(4):221-224
This paper describes a context-based dynamic messaging system. It uses schedule information and location information of the
message addressee. According to the addressee's communication context (schedule, location, and available media), the system
selects the most suitable telephone number or e-mail address, and redirects each incoming message dynamically. It also writes
the schedule and location information of users into an HTML file which users can share on the WWW. It will work as mobile
groupware for mobile workers. Evaluating the system during a two-month experiment in Tokyo, we found that our system produced
smooth communication and a greater feeling of teamwork. 相似文献
948.
Toshiaki Kusunoki Masakazu Sagawa Mutsumi Suzuki Etsuko Nishimura Mitsuharu Ikeda Kazutaka Tsuji 《Journal of the Society for Information Display》2010,18(12):1127-1134
Abstract— Large‐screen (32‐in. WXGA and 17‐in. VGA) displays using metal—insulator—metal (MIM) cathode arrays have been developed. A cathode structure with low‐resistance electrodes and low‐capacitance emitters shortens signal delay and decreases the voltage drop in large MIM‐cathode arrays. By using a dual‐scan method, the signal delay was suppressed to less than 30% of the horizontal scan time in the 32‐in. WXGA panel. Emission efficiency of the cathode array was improved to 3% by reducing the surface work function of the top electrode from 4.7 to 3.9 eV. The cathode life was also improved to more than 10,000 hours. The display panel incorporating the cathode arrays and high‐efficiency P22‐phosphor screens with 3‐mm spacers showed high screen brightness (average brightness, 378 cd/m2; peak brightness, 832 cd/m2) at an anode voltage of 10 kV. 相似文献
949.
Shigeru Kubota Jonathan Rubin Tatsuo Kitajima Takao Nakamura 《Artificial Life and Robotics》2010,15(2):185-188
Spike-timing-dependent plasticity (STDP) induces competition among inputs, which is required for the construction of functional
neuronal circuits, while maintaining the basic features of Hebbian plasticity. Here, we theoretically examine the competitive
function of STDP incorporating a metaplastic activity-dependent feedback (ADFB) mechanism, wherein higher postsynaptic activity
suppresses LTP, in cases where a neuron receives two groups of correlated inputs. We demonstrate that there are four distinct
types of competitive properties depending on the relative input frequency between the different groups and the correlation
time among the inputs within the same group. (1) Competition with a bi-stable synaptic weight distribution (for identical
frequencies and brief correlation). (2) No competition (for identical frequencies and prolonged correlation). (3) Competition
preferring strong input activity (for different frequencies and brief correlation).(4) Competition preferring weak input activity
(for different frequencies and prolonged correlation). This may suggest that ADFB regulation can modulate the Hebbian competition
properties associated with STDP to increase its ability to reflect input firing properties. 相似文献
950.
Sigenori Tsuji Katsuhiko Maki Ken-ichi Kumagai 《Journal of Low Temperature Physics》1999,117(5-6):1683-1687
Hole-doping effects are investigated by Cu-NMR for single crystal of Sr
14–x
Ca
x
Cu
24
O
41. The charge order of Cu
2+
and Cu
3+
and spin dimer ground state in the chain of Sr
14
Cu
24
O
41
are proved by NMR study. The magnetic order of Cu spins in the chain and also the field-induced staggered moments at the ladder Cu site are confirmed for 3x6 of Sr
14–x
La
x
Cu
24
O
41. 相似文献