The design of everyday things don norman

... available from the appearance of the objects the psychology of everyday things. And part comes from the ability of the designer to make the operation clear, to project a good image of the operation, ... came together. These ideas, the respite of the sabbatical. My experiences over the years fighting the difficulties of poor design, of equipment that...

Ngày tải lên: 26/05/2014, 07:46

... effective depth d of the mat by checking for diagonal tension shear at the columns (ACI 318 11.12.2.1c); 7) From the all the moment diagrams of all the strips in one direction, choose the maximum positive ... modified curves for L/B ≠ 1 (on the next slide), 1) At the top of the clay layer, z/B = 18 ft / 40 ft = 0.45 and L/B = 60 ft / 40 ft = 1.50 2) At the middle o...

Ngày tải lên: 16/10/2012, 10:43

... accuracy of the workpiece mainly depend on the axial rigidity of the spindle headstock and of the rotary table. Therefore, the rigidity of the thrust bear- ings is especially important. To increase the ... conditions as the expansion of the rotating parts due to the effects of heat and centrifugal force do not cause jamming of the outer rings in the housi...

Ngày tải lên: 25/12/2013, 05:17

... clearance Due to the tight fits, the inner ring of the bearing is expanded and the outer ring with the roller-and-cage assembly is contracted. Thus the radial clearance of the bearing is reduced ... V1. Bearing selection The selection of the bearings is primarily based on the main thrust, which is directed downwards. It is made up of the weight of the rotor...

Ngày tải lên: 25/12/2013, 05:17

... From the frame of reference of any one point, then, it is possible to say which of the other two points is to the right. 5 SCIENCE OF EVERYDAY THINGS VOLUME 2: REAL-LIFE PHYSICS Clearly, the judgment ... thus the only variable for the water displaced is its volume. For the buoyant force on the ship, g will of course be the same, and the value of V will be...

Ngày tải lên: 19/01/2014, 13:04

... Typically, the designer designs a product with minimal knowledge about the capabilities and limitations of the manufacturing technology. The designer then tries to find out if the design can be ... that the designer can easily interact with the system. Ranking of Redesign Alternatives Another area requiring research attention in the context of generation of redes...

Ngày tải lên: 19/01/2014, 18:20

... assumed that the production rate (r ijt ) of the main product j of each such scheme is proportional to the capacity of the plant. where M i denotes the index set of main products of the alternative ... chop off the solution point from the space of the LP relaxation polyhedron. The process is repeated, thereby reducing the gap between the MILP and its LP re...

Ngày tải lên: 19/01/2014, 18:20

... selection The axial load of 130 kN is made up of the weight of the rotor and the two variable top and bottom fan im- pellers as well as the thrust of these fan impellers. They are supported by the ... V1. Bearing selection The selection of the bearings is primarily based on the main thrust, which is directed downwards. It is made up of the weight of the rot...

Ngày tải lên: 23/01/2014, 04:20

... bearing aspects of the applications. The operation of the machine allows conclusions to be drawn about the operating conditions which dictate the bearing type and design, the size and arrangement, ... roughening of the surfaces (increased running noise). Bearing dimensioning The size of the bearings is dictated by the shaft diame- ter, which in turn is based on t...

Ngày tải lên: 23/01/2014, 04:20

... individuals. The lack of a unified “theory of ecology” and the existence instead of a fragmented body of “ecological theory”is evidenced by the relative use of these two terms in the scientific ... alternative to the “theory of evolution”for explaining the diversity of life on Earth and the ex- istence of millions of different species. Opponents of this view...

Ngày tải lên: 25/01/2014, 08:20