• Convolution CodesConvolution Codes

    In the convolutional codes (also called trellis codes), the redundancy that must be added to allow error correction at the receiver is continuously distributed in the channel bit stream. Therefore, as opposed to the block codes, which operate on finite-length blocks of message bits, a convolutional encoder operates on continuous sequences of messag...

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  • Complex disturbance models for ofdm - Based systemsComplex disturbance models for ofdm - Based systems

    In the consideration above, an on–off error model is defined describing the availability of a transmission channel. However, if a disturbance impulse occurs, it can affect a variable number of OFDM subcarrier frequencies depending on its characteristics, spectral power, origin, and so on. Therefore, the disturbances have to be modeled not only in t...

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  • Network SegmentationNetwork Segmentation

    A PLC access network can be realized to include a whole low-voltage power supply network or to include only a part of a supply network. To reduce the number of users per PLC system and the network length, it is possible to divide the low-voltage network into several parts (e.g. one PLC system per network section). In this case, several PLC systems ...

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  • Creating a new panel pageCreating a new panel page

    The list of items includes recent comments posted on the site, a list of new users who were recently added to the site (“Who’s new”), and a list of currently logged-in users (“Who’s online”). If you’ve installed contributed modules, you may find additional items that are enabled through the additional modules. Next, click on the Menus link in the l...

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  • Beginning drupal - Content typesBeginning drupal - Content types

    This page lists all of the fields that are associated with our content type, and provides the ability to define basic display attributes for the label and content for each of the fields. There are two sets of values that we can set: one for the Teaser view and the Full Node view. If you click on the select list for Labels, you will find that there ...

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  • Programming AutoCADProgramming AutoCAD

    Often you want to execute a procedure based on a certain condition. One way of doing this is with the IF statement, which does one thing if a statement is true and another thing if it is false. In other words, the operation is conditioned on the truth of a certain statement. Looping is an important part of programming. Frequently you want to execut...

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  • Rendering in 3D - Creating a SceneRendering in 3D - Creating a Scene

    Working with lists of materials Materials are saved in a file with the extension .mli (materials library). The default materials library is render.mli. The left side of the Materials Library dialog box represents materials in the current drawing. The right side of the dialog box represents the entire list of materials provided by AutoCAD. In the Cu...

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  • Drawing in Two Dimensions - Step - by - Step: Creating Text StylesDrawing in Two Dimensions - Step - by - Step: Creating Text Styles

    1. Open ab13-b.dwg from your CD-ROM. 2. Save the file as ab13-03.dwg in your AutoCAD Bible folder. 3. Choose Format➪Text Style to open the Text Style dialog box. Click New. In the New Text Style dialog box, type Notes and click OK. 4. From the Font Name drop-down list, choose romans.shx. In the Height text box, change the height to 1/16". In t...

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  • Drawing in Two DimensionsDrawing in Two Dimensions

    To trim an object, choose Trim from the Modify toolbar. You cannot select objects before starting the TRIM command. AutoCAD displays the Current settings: Projection=UCS, Edge=None Select cutting edges . Select objects: prompt. AutoCAD lets you know the values of the two system variables that affect trimming. The Projection setting is used only for...

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  • AutoCAD Basics - Unit TypesAutoCAD Basics - Unit Types

    If you are using engineering or architectural units, AutoCAD displays partial inches differently than the format you must use to type them in. You must type coordinates without any spaces because AutoCAD interprets a space as equivalent to pressing the Enter key and ends your input. Use a hyphen between whole and partial inches, for example, 3'2-1/...

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