Direct Form Synthesis: Element Substitution and Operational Simulation

2021 ◽  
pp. 244-298
Keyword(s):  
Element Substitution ◽  
Direct Form

scholarly journals Off-Shell Noether Currents and Potentials for First-Order General Relativity

Symmetry ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 348
Author(s):  
Merced Montesinos ◽  
Diego Gonzalez ◽  
Rodrigo Romero ◽  
Mariano Celada
Keyword(s):  
General Relativity ◽  
Vector Fields ◽  
Killing Vector ◽  
Spherically Symmetric ◽  
Killing Vector Fields ◽  
Arbitrary Vector ◽  
Four Dimensions ◽  
First Order ◽  
Direct Form ◽  
Definition Of

We report off-shell Noether currents obtained from off-shell Noether potentials for first-order general relativity described by n-dimensional Palatini and Holst Lagrangians including the cosmological constant. These off-shell currents and potentials are achieved by using the corresponding Lagrangian and the off-shell Noether identities satisfied by diffeomorphisms generated by arbitrary vector fields, local SO(n) or SO(n−1,1) transformations, ‘improved diffeomorphisms’, and the ‘generalization of local translations’ of the orthonormal frame and the connection. A remarkable aspect of our approach is that we do not use Noether’s theorem in its direct form. By construction, the currents are off-shell conserved and lead naturally to the definition of off-shell Noether charges. We also study what we call the ‘half off-shell’ case for both Palatini and Holst Lagrangians. In particular, we find that the resulting diffeomorphism and local SO(3,1) or SO(4) off-shell Noether currents and potentials for the Holst Lagrangian generically depend on the Immirzi parameter, which holds even in the ‘half off-shell’ and on-shell cases. We also study Killing vector fields in the ‘half off-shell’ and on-shell cases. The current theoretical framework is illustrated for the ‘half off-shell’ case in static spherically symmetric and Friedmann–Lemaitre–Robertson–Walker spacetimes in four dimensions.

‘I will not put this request at the very beginning’

2019 ◽  
Vol 4 (1) ◽  
pp. 37-58
Author(s):  
Qun Zheng ◽  
Ying Xu
Keyword(s):  
Peer Interaction ◽  
Language Use ◽  
Peer To Peer ◽  
Language Pedagogy ◽  
Power Difference ◽  
Direct Form ◽  
L2 Learners

Pragmatic (in)felicity in requests refers to the (in)appropriateness and (im)politeness of one's language use. It has been a great challenge to L2 learners, as they are likely to compose grammatically correct but pragmatically infelicitous requests. Such infelicity could be associated with pragmalinguistic and sociopragmatic factors, yet whether L2 learners are aware of those factors has been underexplored. To understand the effects of power, imposition, and modifications on email perception, we designed a matched guise test for 224 Chinese L2 learners, who were instructed to rate from 1 (very inappropriate/impolite) to 5 (very appropriate/polite) on four email requests (Power±; Imposition±). We found that (1) learners are highly aware of pragmalinguistic factors because they perceive requests mitigated by internal and external modifications as more appropriate and polite (p < .05), (2) learners have limited awareness of power difference as they rank direct form as inappropriate in peer-to-peer interaction, and (3) learners cannot realise fully the sociopragmatic factors involved in high-imposition situations. The awareness of pragmatic (in)felicity among learners seems to be underdeveloped as regards degree of power and imposition. The findings could have some implications in language pedagogy.

Effect of transition metal element substitution on magnetoelectric properties of BiFeO3-BaTiO3 ceramics

2021 ◽  
Vol 859 ◽  
pp. 158224
Author(s):  
Miao Miao Niu ◽  
Juan Liu ◽  
Tu Lai Sun ◽  
Run Zu Jiang ◽  
Dian Hui Hou ◽  
...  
Keyword(s):  
Transition Metal ◽  
Element Substitution ◽  
Magnetoelectric Properties ◽  
Transition Metal Element ◽  
Metal Element

scholarly journals Sharpening of the multistage modified comb filters

2011 ◽  
Vol 8 (3) ◽  
pp. 281-291 ◽  
Author(s):  
Marko Nikolic ◽  
Miroslav Lutovac
Keyword(s):  
Comb Filter ◽  
Polyphase Filter ◽  
Filter Structure ◽  
Direct Form ◽  
Comb Filters ◽  
Decimation Filter ◽  
Last Stage ◽  
Positive Integers

This paper describes the application of filter sharpening method to the modified comb filter (MCF) in the case of decimation factor, which is product of two or more positive integers. It is shown that in the case of multistage decimation with MCF, filters in each stage are also MCF. Applying the sharpening to the decimation filter in the last stage provides very good results, with savings in the number of operations comparing to the case of sharpening of the complete filter. Direct-form FIR polyphase filter structure is proposed for the filters in each stage.

scholarly journals Unique Methods of Visual Presentation With Respect to Accident Reconstruction

1986 ◽  
Vol 3 (1) ◽  
Author(s):  
Frank H. Johnson
Keyword(s):  
Aerial Photography ◽  
Visual Presentation ◽  
The Other ◽  
Accident Reconstruction ◽  
Engineering Communication ◽  
Automobile Accident ◽  
Direct Form ◽  
Forensic Engineering

Obviously, communication is one of the most important aspects of forensic engineering. Communication is certainly important between both the engineer and the lawyer as well as the engineer and the jury. Of course, communication involves not only sending a message to someone but also making sure that the message is understood by the person receiving it. Speaking and sending letters are two methods of sending a message. However, perhaps a more direct form of communication is visual. The old adage 'a picture is worth a thousand words' has been proven many, many times. Therefore, this discussion deals with two very specific methods of achieving communication through visual presentation. First of all, understand that these two methods are directed primarily toward accident reconstruction. For purposes of illustration, an automobile accident will be used as an example; however, these methods can be applied to other types of accidents as well. The first method, one involving aerial photography, is currently under development. The other method, which is primarily graphic, is already developed and available through several graphic companies or individuals.

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