In this paper we describe a Python- and Tkinter-based visual-programming environment called ViPEr. This tool enables non-programmers to build computational and visualization networks interactively. Computational nodes can be placed onto a canvas and their input and output ports can be connected using the mouse. The connections between the nodes define a directed graph that will be used to propagate data and trigger the execution of nodes that have new input data. ViPEr is, in appearance, similar to programs such as AVS [Upson et al. 89] from Advanced Visual Simulations Inc, or OpenDX [DX 93] from IBM, but presents some fundamental differences which will be pointed out throughout this paper. Several examples of applications will be used to illustrate ViPEr’s design and current range of capabilities.
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In October of 1976 I observed that a certain algorithm – parallel reduction – was associated with monoids: collections of elements with an associative operation. That observation led me to believe that it is possible to associate every useful algorithm with a mathematical theory and that such association allows for both widest possible use and meaningful taxonomy. As mathematicians learned to lift theorems into their most general settings, so I wanted to lift algorithms and data structures. One seldom needs to know the exact type of data on which an algorithm works since most algorithms work on many similar types. In order to write an algorithm one needs only to know the properties of operations on data. I call a collection of types with similar properties on which an algorithm makes sense the underlying concept of the algorithm. Also, in order to pick an efficient algorithm one needs to know the complexity of these operations. In other words, complexity is an essential part of the interface to a concept.
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We present a vision system for the 3-D model- based tracking of unconstrained human movement. Using image sequences acquired simultaneously from multiple views, we recover the 3-D body pose at each time instant without the use of markers. The pose- recovery problem is formulated as a search problem and entails finding the pose parameters of a graphical human model whose synthesized appearance is most similar to the actual appearance of the real human in the multi-view images. The models used for this purpose are acquired from the images. We use a decomposition approach and a best-first technique to search through the high dimensional pose parameter space. A robust variant of chamfer matching is used as a fast similarity measure between synthesized and real edge images.
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Borland Delphi is known to be a great environment for the development of stand-alone and client-server applications on the Microsoft Windows platform. Its virtues range from full OOP support to visual development, in a unique combination of power and ease. However, the new frontier of development is now Internet programming. What has Delphi got to offer in this new context? Which are the features you can rely upon to build great Internet applications with Delphi? That’s what this paper intends to reveal. We’ll see that Delphi can be used:
• For direct socket and TCP/IP programming;
• In conjunction with third-party components that implement the most common Internet protocols, on the client or the server side;
• To produce HTML pages on the server side, with the WebBroker and Internet Express architectures;
• As well as to work with Microsoft’s core technologies, including MTS, COM, ASP, and ActiveX.
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First generation wireless systems, which primarily provide analog voice service, are widely in use worldwide. Second generation systems support digital voice/data traffic; some of these systems are already deployed or undergoing deployment. Third generation wireless networks will ultimately carry multimedia traffic that are characterized by combination of different informaion streams of diverse nature (e.g., voice, video, image, data). Some of the salient features of multimedia applications are high speed and changing bit rates (periodic and bursty arrivals), several virtual connections over the same access, synchronization of different information streams, and various service/deliveIy requirements (QoS).
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Web services, an emerging paradigm for architecting and implementing business collaborations within and across organizational boundaries, are currently of interest to both software vendors and scientists. In this paradigm, the functionality provided by business applications is encapsulated within web services: software components described at a semantic level, which can be invoked by application programs or by other services through a stack of Internet standards including HTTP, XML, SOAP, WSDL and UDDI [3,18]. Once deployed, web services provided by various organizations can be inter-connected in order to implement business collaborations, leading to composite web services.
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The EPICS toolkit consists of a set of software components with which Application Developers can create a control system. The basic component types are:
•OPI
Operator Interface. A UNIX- or NT-based workstation or PC which can run various EPICS tools—the “clients.”
•IOC
Input Output Controller. A VME/VXI-based chassis containing a Motorola 68K or PPC processor with various VME I/O modules for analog and digital signals, and for access to field buses such as Allen-Bradley, GPIB, CANbus or CAMAC.
•LAN
TCP/IP-based Local Area Network. A communication network which connects the IOCs and OPIs. EPICS provides a software com- ponent, Channel Access, which provides network transparent commu- nication between every client—such as OPI—and an arbitrary number of servers—such as IOC.
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Beginning with version 2.5 (currently in Preview Edition) building Silverlight 2 applications, and especially assembling the User Interface components such as items from the toolbox, and layout controls, is easier than ever. A Note on This Tutorial. The history of the material for this tutorial is that Scott Guthrie wrote a terrific introduction to this material at the end of February, which he gave me permission to turn into a series of videos, currently (or soon to be) available on Silverlight.NET. This tutorial completes the circle by building on the videos and integrating the material into the Silverlight Tutorial series. The project we’re setting out to build is very similar to the Silverlight chat service built by ScottGu, and is shown in Figure 5-1
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