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Basics of the Unix System
Published in Paul W. Ross, The Handbook of Software for Engineers and Scientists, 2018
F. Sanders Alton, Pickering Robert
“Sed” is a stream editor. It accepts a file (or files) as input and applies one or more editing commands to each line with the file. It is particularly useful for doing global editing of several files. Sed uses the command set from the line editor ed. For example, suppose I wish to substitute the word “sack” for “bag” in file “fruit.” I could issue the command sed ‘s/bag/sack/g’ fruit which would yield The string in single quotes constitutes an editor command. The first s indicates that a subsititution is desired and the word “bag” indicates the word to be replaced by “sack.” The final g indicates that all occurrences of “bag” in the line should be replaced. Commonly a set of editing commands are put into a “script” file so that a number of different commands can be applied to the same file. For example, we could create the following script in the file called “scriptfile” to substitute “sack” for “bag” or “Bag” and “case” for “box” or “Box.” We will create “scriptfile” as follows: s/bag/sack/g s/Bag/sack/g s/box/case/g s/Box/case/gthen we can issue sed -f scriptfile fruit to produce There is a full set of editing commands that can be used with sed to perform complex editing tasks.
Do remote boundary conditions affect photodetection?
Published in Journal of Modern Optics, 2019
S. A. Wadood, Justin T. Schultz, A. Nick Vamivakas, C. R. Stroud
Why is there a difference between Equation (A8) and Equation (25), when both express shot noise in homodyne detection? There is debate in the literature (14,15) regarding the cause of shot noise in homodyne detection. One can think of either the local oscillator or the vacuum modes from the empty port of the beam splitter as two alternative causes of shot noise (19). By using modified vacuum modes, the MVN effect and Equation (A8) extend, rather hastily, the vacuum interpretation of shot noise. Due to the Fluctuation-Dissipation theorem (29), care must be taken in this extension. If the vacuum modes are modified, the dissipation properties of the detector should change accordingly, as we have shown above. Conventional photodetector theory, especially the theorems of the operator formalism of (14), assumes the detector to interact with free space vacuum, and cannot be applied directly to the MVN problem in which the reservoir is spatially structured. Equation (A8), which follows from such a direct application of operator photodetection theory to the MVN problem, predicts that the photocurrent noise varies with the mirror distance while the mean current remains the same. This is a dilemma, since we know that vacuum modes cannot excite a photoelectron! Even thoughEquation (A8) was derived in a QED formalism, improper application of the Fluctuation-Dissipation theorem makes its prediction qualitatively similar to a stochastic electrodynamics (SED) treatment, which treats vacuum fluctuations as zero mean classical fluctuations of the field (30–32). In this qualitative sense, Equations (A8) and (25) refer to two different predictions of SED and QED respectively.
Exploring multiple eco-routing guidance strategies in a commuting corridor
Published in International Journal of Sustainable Transportation, 2018
Jorge M. Bandeira, Paulo Fernandes, Tânia Fontes, Sérgio Ramos Pereira, Asad J. Khattak, Margarida C. Coelho
In this section, the overall impacts in terms of STT, system CO2, system NOx, and SED costs according to different route guidance strategies (SO and UE) with different objectives (CO2, NOX, ED) are presented. Table 3 shows the overall impacts for both levels of network saturation considering a traditional UETT assignment. Thus, assuming that user's route choice behavior is primarily affected by travel time, Figure 6 compares each innovative route guidance strategy with the standard flow distribution (UETT) presented in Table 3.
A Cost-Emission-Based Multi-objective Dynamic Economic Dispatch Considering Solar-Wind Curtailment Cost
Published in IETE Journal of Research, 2021
Amit Rai, Ashish Shrivastava, K. C. Jana
The economical and reliable supply of power with the number of different generators, to the end consumer, has gained ample attention [24]. This problem of ED is of two types: static economic dispatch (SED) and dynamic economic dispatch (DED). The difference between these two is of ramp-up and ramp-down restrictions, which are a part of DED and not specified in SED [25]. This optimal allocation of power from the generating units is an approach to decide unit commitment and is a nonlinear problem in microgrids [26] and can be addressed through soft computing techniques [27].