Mathematics The Civil Engineering Handbook

... point called the origin These two lines constitute the coordinate axes; the horizontal line is the x-axis and the vertical line is the y-axis The positive direction of the x-axis is to the right, ... present The values of these units in terms of the corresponding SI units are not exact, since they depend on the values of the physical constants e (for the electronvolt) and NA (for the unified ... between the ° sign and the letter C (The symbol °K, and the symbol °, should no longer be used.) © 2003 by CRC Press LLC Units in Use Together with the SI These units are not part of the SI,...

The electrical engineering handbook CH107

... coefﬁcients in the same manner as the coefﬁcient of utilization The room position multiplier is a function of the room cavity ratio and of the location in the room of the point where the illumination ... both Reduce the area of high luminance causing the glare condition Increase the angle between the glare source and the line of vision Increase the luminance of the area surrounding the glare source ... Ratios The ability to see details depends on the contrast between the detail and its background The greater the contrast difference in luminance, the more readily the seeing task is performed The...

The electrical engineering handbook CH051

... tensile stress in the x-direction, for example, will strain the lattice in the xy-plane and destroy the three-fold symmetry, thereby lifting the degeneracy of the energy minima However, the four-fold ... permission.) According to the deformation potential theory, the strain will shift the energy of all the states in a given band extremum by the same amount, i.e., the valley moves along the energy scale ... perpendicular to the valley For an applied E ﬁeld parallel to the stress, the conductivity will increase (i.e., the resistivity decreases) relative to the unstressed state because of the increase in the number...

The electrical engineering handbook CH052

... in the characterization of the latter Some authors choose to discuss the Hall effect in terms of the Hall angle, f, shown in Fig 52.1, which is the angle between the net electric eld and the ... because of the Lorentz force on the conducting charges and is of just such a magnitude that in combination with the Lorentz force there is no net current in the y direction The angle f between the current ... (52.11) where the subscript species the band number and m i , the effective mass for each band These masses need not be equal nor the same as the free electron mass In effect, some of the features...

The electrical engineering handbook CH053

... superconductor The correlations of the electrons in the superconductor must lower the overall energy of the system or else the material would not be superconducting in the rst place Because the critical ... (53.5) where the left side of the expression is the power owing into the region By taking the time derivative of the energy density and appealing to Faradays and Ampốres laws to nd the time derivatives ... Under the two-uid model, the electrical current density, J, is carried by both the uncorrelated (normal) electrons and the superelectrons: J = Jn + Js where Jn is the normal current density The...

The electrical engineering handbook CH054

... where G T is the thermal conductance from the element to the environment, t T is the thermal time constant of the element, t E is the electrical time constant of the element, R G is the electrical ... constant, T is the absolute temperature, tand is the dielectric loss tangent of the detector material, C E is the electrical capacitance of the element, and C A is the input capacitance of the detector ... electrical resistance across the element, h is the emissivity of the element for the radiation being detected, and A is the sensitive area of the element It is easy to show that the response of a pyroelectric...

The electrical engineering handbook CH055

... overcompensates for the current due to the deep traps The mobility of the free charge carriers is determined by the depth of the traps, the eld resulting from the trapped charges, and the temperature ... assumed not to disturb the trapped charge; the received electrical signal is then correlated with the acoustical wave to determine the prole of the trapped charge Errors in the measurement would ... be thermally excited to move from the valence to the conduction band and that under the inuence of an external eld they will be impelled to move in the direction of the eld, colliding with the...

The electrical engineering handbook CH056

... employed The mercury thermometer was mentioned in the Introduction as a nonelectrical sensor The most commonly used electrical temperature sensors are thermocouples, thermistors, and resistance thermometers ... temperature As the electrons in the metal gain thermal energy, they move about more rapidly and undergo more frequent collisions with each other and the atomic nuclei These scattering events reduce the ... of the wire to a cantilever beam, with one end of the wire at the attached beam end and the other at the free end The cantilever beam free end moves in response to an applied force, such as the...

The electrical engineering handbook CH057

... data, the same thermal process can be applied while reversing the direction of the bias magnetic eld To read the stored information optically, the Kerr effect is used to detect the presence of these ... light waves The superposition of these two waves produces a linearly polarized wave The plane of polarization of the resultant wave rotates as one circular wave overtakes the other The rate of ... another 45 degrees through the Faraday material, and, because its polarization is now 90 degrees from the incident beam, is deected by the rst calcite prism The four ports of the circulator then...

The electrical engineering handbook CH089

... resistor and the other as a voltage probe where either can function in either role For the Y coordinate value the top layer is the voltage probe, and the voltage is applied by the controller to the bottom ... on the glass, and the time of arrival of the waves at the receivers is known because the wave velocity is known The placing of a ﬁnger on the glass weakens the signal and the location of the ... across the substrate The Y axis is scanned in the same fashion after the X wave dies out Then, when the ﬁnger touches the substrate, its water content absorbs some of the energy in the wave, and the...

The electrical engineering handbook CH106

... vehicles, etc are familiar terms There is some variation among them relative to the electronics embedded in the systems and the options available to the driver The same is true for railroads, ... All of these subsystems interact with each other and many also interact with subsystems external to the vehicle Some of the initial design considerations for vehicles include: • Will the vehicle ... which cars may soon have analogous functions The electrical and electronic systems and controls account for 15 to 30% of the cost of the vehicle The major vehicle subsystems include propulsion,...

The electrical engineering HandbookSN09

... know the important aspects of the design which require the knowledge of electrical engineering, the architecture may not be good Given that the implementation of the architecture has to serve ... which the integrated circuits are made One also has to deal with the devices and device physics to make the most efﬁcient transistors of which computing sytems are built The knowledge of electrical ... system is similar to building a house — at the very beginning one cannot be bothered with all the details involved in the process, such as plumbing and electrical wiring Similarly a process of...

The electrical engineering handbook SN03

... INCREDIBLE CHANGES in the technology associated with electronics over the past three decades have certainly been the driving force for most of the growth in the ﬁeld of electrical engineering Recall ... years ago the transistor was a novel device and that the majority of electronic systems still used vacuum tubes Then look at the section headings in the following chapters and appreciate the range ... realizations There are areas of overlap with other chapters in the Handbook, such as those covering electrical effects and devices, biomedical electronics, digital devices, and computers The contributors...

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