《🔥重庆时时彩什么叫对吗》Draughting, or drawing, as it is more commonly called, is a means by which mental conceptions are conveyed from one person to another; it is the language of mechanics, and takes the place of words, which are insufficient to convey mechanical ideas in an intelligible manner.During the meeting of the British Association in Belfast (1874), the committee appointed to investigate the means of teaching Physical Science, reported that "the most serious obstacle discovered was an absence from the minds of the pupils of a firm and clear grasp of the concrete facts forming a base of the reasoning processes they are called upon to study; and that the use of text-books should be made subordinate to an attendance upon lectures and demonstrations."
In the class of mechanical knowledge that has been defined as general, construction comes in the third place: first, machine functions; next, plans or adaptation of machines; and third, the manner of constructing machines. This should be the order of study pursued in learning mechanical manipulation. Instead of studying how drilling-machines, planing-machines or lathes are arranged, and next plans of constructing them, and then the principles of their operation, which is the usual course, the learner should reverse the order, studying, first, drilling, planing, and turning as operations; next, the adaptation of tools for the purposes; and third, plans of constructing such tools.
In making up the time charged to different machines during their construction, a good plan is to supply each workman with a slate and pencil, on which he can enter his time as so many hours or fractions of hours charged to the respective symbols. Instead of interfering with his time, this will increase a workman's interest in what he is doing, and naturally lead to a desire to diminish the time charged to the various symbols. This system leads to emulation among workmen where any operation is repeated by different persons, and creates an interest in classification which workmen will willingly assist in.
Having thus far treated of such general principles and facts connected with practical mechanics as might properly precede, and be of use in, the study of actual manipulation in a workshop, we come next to casting, forging, and finishing, with other details that involve manual as well as mental skill, and to which the term "processes" will apply.It is a strange thought that with all the order, system, and regularity, existing in nature, there is nothing but the movements of the heavenly bodies constant enough to form a base for gauging tests. The French standard based upon the calculated length of the meridian may be traced to this source.
The advantages gained by milling, as stated, are speed, duplication, and accuracy; the disadvantages are the expense of preparing tools and their perishability.
CHAPTER XXX. TURNING LATHES.Institute of Plasma Physics, Hefei Institutes of Physical Science (ASIPP, HFIPS) undertakes the procurement package of superconducting conductors, correction coil, superconducting feeder, power supply and diagnosis, accounting for nearly 80% of China's ITER procurement package.
"I am so proud of our team and it’s a great pleasure for me working here," said BAO Liman, an engineer from ASIPP, HFIPS, who was invited to sit near Chinese National flay on the podium at the kick-off ceremony to represent Chinese team. BAO, with some 30 ASIPP engineers, has been working in ITER Tokamak department for more than ten years. Due to the suspended international traveling by COVID-19, most of the Chinese people who are engaged in ITER construction celebrated this important moment at home through live broadcasting.
One of ASIPP’s undertakes, the number 6 poloidal field superconducting coil (or PF6 coil) , the heaviest superconducting coil in the world, was completed last year, and arrived at ITER site this June. PF6 timely manufacturing and delivery made a solid foundation for ITER sub-assembly, it will be installed at the bottom of the ITER cryostat.
Last year, a China-France Consortium in which ASIPP takes a part has won the bid of the first ITER Tokamak Assembly task, TAC-1, a core and important part of the ITER Tokamak assembly.
Exactly as Bernard BIGOT, Director-General of ITER Organization, commented at a press conference after the ceremony, Chinese team was highly regarded for what they have done to ITER project with excellent completion of procurement package.
The kick-off ceremony for ITER assembly (Image by Pierre Genevier-Tarel-ITER Organization)
the number 6 poloidal field superconducting coil (Image by ASIPP, HFIPS)
ITER-TAC1 Contract Signing Ceremony (Image by ASIPP, HFIPS)
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