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991.
Munasinghe S.R. Nakamura M. Goto S. Kyura N. 《IEEE transactions on systems, man and cybernetics. Part C, Applications and reviews》2001,31(2):159-167
Presents a general solution to the contouring problem of industrial robot arms, under the constraints of assigned Cartesian velocity and joint torque/acceleration. The proposed solution is an off-line trajectory generation algorithm and, therefore, it possesses significant industrial implications, as no hardware changes are needed for its implementation. According to the proposed method, the maximum utility of joint torque/acceleration is guaranteed to be bound to the assigned velocity constraint. In the proposed method, a realizable trajectory is generated from the objective trajectory and its delay dynamics are compensated for by using a forward compensator. The proposed method has been experimented with using a Performer MK-3s (PMK-3s) industrial robot arm, and optimum contouring has been realized 相似文献
992.
993.
Gas and liquid velocities in laboratory scale trickle bed reactors are one or two orders of magnitude lower than those in commercial reactors. Then, the kinetic data may include the external effects. This shortcoming of laboratory scale trickle bed reactor can be resolved by diluting the catalyst bed with fine inert particles. The catalyst bed dilution increases dynamic liquid holdup, pressure drop, gas–liquid mass transfer coefficient. Hydrogenation of 2-phenylpropene on Pd/Al2O3 was performed with the trickle bed reactor diluted with fine inert particles and the coiled tubular flow-type reactor to compare the kinetics with that of the basket type batch reactor. The trickle bed reactor diluted with fine inert particles is suitable to obtain the reaction rate without external effects even if the liquid velocity is low. The coiled tubular flow-type reactor should be used at high gas velocities. 相似文献
994.
Nakamura M. Munasinghe S.R. Goto S. Kyura N. 《Mechatronics, IEEE/ASME Transactions on》2000,5(4):437-440
Contour control of a robot arm is an act of the end-effector tip being moved along a reference Cartesian path, with an assigned velocity. When torque saturation occurs, and lasts for some time, contour deteriorations result. In addition, system delay dynamics also causes contour deteriorations. In this paper, an offline trajectory generation algorithm is described, which achieves both optimum avoidance of torque saturation and delay dynamics compensation 相似文献
995.
Kenta Goto Hisakazu Sunada Kazumi Danjo Yorinobu Yonezawa 《Drug development and industrial pharmacy》1999,25(8):869-878
Recently, a novel type of multipurpose excipient (MPE) with high binding characteristics and high fluidity has been developed. In this study, the capabilities of MPEs (Ludipress and Microcelac) were compared with those of excipients in general use. Also, the effects on powder and tableting characteristics of the physical properties and contents of active ingredients were examined in tablets prepared with these MPEs by the direct compression method. Multipurpose excipients mixed with adjuvants such as fillers, binders, lubricants, disintegrants, and the like show superior fluidity and compressibility. Tablets containing very small amounts of highly active ingredients with little dispersion were prepared. However, with increases in active ingredient content, each of the physical properties was affected strongly by the properties of the active ingredient. Tablets with appropriate hardness and disintegration characteristics could be prepared by mixing of different types of MPEs. 相似文献
996.
An explanation of the wetting and the mutual diffusion mechanisms of liquid metals using ab-initio atomic orbital calculation 总被引:1,自引:0,他引:1
Hiromichi Toyota Takashi Ide Hidetsugu Yagi Hidekazu Goto Katsuyoshi Endo Kikuji Hirose Yuzo Mori 《Computational Materials Science》1999,14(1-4):129-131
In this report, in order to clarify fundamentally the wetting phenomenon between pure material surfaces, we propose a new method for the experimental evaluation and consider quantitatively the wetting mechanism from the microscopic standpoint of the chemical reaction between interfacial atoms. Ab-initio molecular orbital calculation was performed to explain the wetting and the mutual diffusion mechanisms. It was found that the calculated binding energies were in good agreement with the interaction energies estimated from measured contact angles, and it was also cleared that the hybridization of the interfacial d-orbitals was one of the most important elements of the mutual diffusion. 相似文献
997.
998.
Goto K. Matsuo J. Tada Y. Sugii T. Yamada I. 《Electron Devices, IEEE Transactions on》1999,46(4):683-689
A low-energy, high-dosage boron ion implantation technology using a decaborane (B10H14) molecule is developed. Since B10N14 consists of ten boron atoms, they are implanted with about a one-tenth lower effective acceleration energy and ten times higher effective beam current compared with those of boron. We demonstrated an ultrashallow boron profile with 0.5 keV effective acceleration energy, which does not cause transient enhanced diffusion (TED) after rapid thermal annealing (RTA). Using this technology, we succeeded in fabricating 0.1-μm PMOSFET's with good device performances and excellent suppression of short-channel effects 相似文献
999.
The relationship between the activity and surface molybdenum species of nitrided 12.5% MoO3/Al2O3 was studied in the hydrodenitrogenation (HDN) of carbazole at 573 K and 10.1 MPa total pressure. The surface molybdenum species were determined by the desorption of nitrogen gas during TPD. The surface area of NH3-cooled Mo/Al2O3 nitrided at 773 and 1173 K was decreased by 8% and 61% from 245 m2 g−1 of the fresh MoO3/Al2O3, respectively. The NH3-cooled Mo/Al2O3 catalysts had slightly higher surface area than the He-cooled catalysts. The HDN rate increased with increasing nitriding temperature in the HDN of carbazole on the nitride catalysts. The NH3-cooled Mo/Al2O3 catalysts nitrided at 1173 K were the most active in carbazole HDN and the He-cooled catalyst nitrided at 773 K was the least. 相似文献
1000.
Liquid-liquid equilibria of ETBE-EtOH-H2O mixtures are measured at 15,25 and 35°C. UNIQUAC and NRTL equations are fitted to the experimental data using ASPEN PLUS. Both the experimental and correlated values of the equilibrium compositions are compared with the values predicted by UNIFAC method. The same procedure is extended to quaternary ETBE-EtOH-H2O-TBA system at low TBA concentration. 相似文献