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排序方式: 共有673条查询结果,搜索用时 31 毫秒
31.
The third part of this series covers, first, the basic function of the conventional voltage controlled short circuiting MIG/MAG welding process (CCC) and the related power source static behaviour. Second, it deals with the mechanisms related to the dynamics of the transfer of the metal drop to the weld pool during short circuit welding. Third, a set of MIG/MAG stability concepts is set out, on which there is no unanimous agreement in current welding studies. Fourth, a proposal by the authors is included. Finally, it demonstrates how systems such as CCC operate and the scientific and technological experience gained by LABSOLDA in this process, from analogue control up to the most modern software controlled versions and the future of the process as part of the advanced control system. 相似文献
32.
岩体中渗流—热—应力耦合作用的理论研究 总被引:3,自引:0,他引:3
推导了岩体中热、流、因耦合问题的耦合控制方程,阐述了方程中各项的物理意义,并且对这一理论结果进行了初步验证。 相似文献
33.
The microbial community structure and successive changes in a mesophilic ethylbenzene-degrading sulfate-reducing consortium were for the first time clarified by the denaturing gradient gel electrophoresis (DGGE) analysis of the PCR amplified 16S rRNA gene fragments. At least ten bands on the DGGE gel were detected in the stationary phase. Phylogenetic analysis of the DGGE bands revealed that the consortium consisted of different eubacterial phyla including the delta subgroup of Proteobacteria, the order Sphingobacteriales, the order Spirochaetales, and the unknown bacterium. The most abundant band C was closely related to strain mXyS1, an m-xylene-degrading sulfate-reducing bacterium (SRB), and occurred as a sole band on DGGE gels in the logarithmic growth phase that 40% ethylbenzene was consumed accompanied by sulfide production. During further prolonged incubation, the dominancy of band C did not change. These results suggest that SRB corresponds to the most abundant band C and contributes mainly to the degradation of ethylbenzene coupled with sulfate reduction. 相似文献
34.
Sone T Nagamori E Ikeuchi T Mizukami A Takakura Y Kajiyama S Fukusaki E Harashima S Kobayashi A Fukui K 《Journal of Bioscience and Bioengineering》2002,94(1):87-91
We have produced micrometer-sized calcium alginate beads referred to as "bio-beads" that encapsulate plasmid DNA molecules carrying a reporter gene. In order to evaluate the efficiency of the bio-beads in mediating genetic transfection, protoplasts isolated from cultured tobacco cells (BY-2) were transfected with bio-beads containing a plasmid that carries the modified green fluorescent protein gene CaMV35S-sGFP. With the bio-beads treatment, approximately ten-fold higher GFP expression was observed after 24 h incubation compared to that with the conventional method using a naked plasmid solution. Transfection was up to 0.22% efficient. These results indicate that bio-beads have a possibility for efficient transformation in plants. 相似文献
35.
This paper aims at constructing a music composition system that composes music by the interaction between human and a computer.
Even users without special musical knowledge can compose 16-bar musical works with one melody part and some backing parts
using this system. The interactive Genetic Algorithm is introduced to music composition so that users’ feeling toward music
is reflected in the composed music. One chromosome corresponds to 4-bar musical work information. Users participate in music
composition by evaluating composed works after GA operators such as crossover, mutation, virus infection are applied to chromosomes
based on the evaluation results. From the experimental results, it is found that the users’ evaluation values become high
over the progress of generations. That is, the system can compose 16-bar musical works reflecting users’ feeling.
Muneyuki Unehara: He received his M.S. in Engineering in 2002 from Institute of Science and Engineering, University of Tsukuba. Currently,
he is a Ph.D. candidate of Graduate School of Systems and Information Engineering, University of Tsukuba. His research interests
include the construction of intelligent systems by considering soft computing techniques and human interface.
Takehisa Onisawa, Ph.D.: He received Dr.Eng. in Systems Science in 1986 from Tokyo Institute of Technology. Currently, he is a Professor in the Graduate
School of Systems and Information Engineering, University of Tsukuba. His research interests include applications of soft
computing techniques to human centered systems thinking. He is a member of IEEE and IFSA. 相似文献
36.
37.
The electronic structures of polyfluoroacetylene and polydifluoroacetylene are discussed on the basis of the tight-binding LCAO-SCF-MO calculations under the CNDO/2 approximations. A method of preparation of these polymers is also proposed. If they can be successfully prepared, they will be promising candidates for new electric conducting materials as alternatives to polyacetylene. 相似文献
38.
Y. Fukui R. Sasaki F. Hataya T. Kashimura 《Metallurgical and Materials Transactions A》1981,12(6):1033-1039
An attempt has been made to develop a cobalt base casting superalloy (30Cr-10Ni-7W-Co) having high creep rupture strength
and ductility for first stage nozzles of gas turbines. In cobalt base superalloys, there was found to exist a close correlation
between the creep rupture strength and MC type carbide forming elements such as Ti, Nb and Zr. In cobalt base alloys with
0.25 wt pct C, precipitation and coarsening of carbides can be reduced by addition of Ti, Nb and Zr. Therefore, by adding
the optimum amount of Ti, Nb and Zr, precipitation of carbides in the alloy reaches such an amount as to give the highest
creep rupture strength. Excess addition of Ti, Nb and Zr does not improve the creep rupture strength. By adding C, creep rupture
strength of the cobalt alloy with Ti, Nb and Zr can be improved and becomes the highest at 0.40 wt pct. C. According to the
experimental results, the creep rupture strength becomes the highest at a value of (Ti + Nb + Zr)/C (atomic ratio) of about
0.3. Contrary to the expectation, it was found in this experiment that the ductility in creep rupture tests increases with
increasing carbon content up to 0.6 wt pct. 相似文献
39.
Higashi T Nagamori E Sone T Matsunaga S Fukui K 《Journal of Bioscience and Bioengineering》2004,97(3):191-195
The direct transfer of genetic materials into mammalian cells is an indispensable technique. We have developed calcium alginate (CA) microbeads which can deliver plasmid DNAs and yeast artificial chromosomes into plant and yeast cells. In this paper, we demonstrate the effective transfection of mammalian cells by CA microbeads immobilizing plasmid DNAs. The transfection was performed using the pEGFP-C1 plasmid containing the cytomegalovirus (CMV) promoter and enhanced green fluorescent protein (EGFP) gene. The transient expression of EGFP was observed 24 h after transfection. The expression efficiency was maximum when the concentration of sodium alginate was 1% and the amount of plasmid DNA was increased to 100 microg. The expression efficiency of our method using CA microbeads is 2-10 times higher than that of the polyethylene glycol (PEG) method. Our results suggest that the CA microbead mediated transfection of mammalian cells effectively delivers genetic materials into mammalian suspension cells. 相似文献
40.
Matsunaga S Ohshio K Harada E Fujiwara S Uchiyama S Fukui K 《Journal of Bioscience and Bioengineering》2004,98(5):384-386
We applied fluorescent microscopy to monitor the damage of DNA upon exposure to gamma radiation. Our developed dosimetry demonstrated that the number of breaks in DNA is proportional to the dose of the irradiation but is not dependent on dose rate of the irradiation and the GC content of DNA. 相似文献