Relational Completeness of Show and Tell Visual Programming Language

In this paper we present the database applications of the Show and Tell Language (STL) and demonstrate the relational completeness of the language. STL is a visual programming language designed for novice computer users who are not familiar with keyboarding. A program can be constructed by using only a pointing device, except for textual data entry. A program can be constructed by using only a pointing device, except for textual data entry. Various programming concepts such as subroutine, iteration, recursion, concurrency, exception, and so forth are represented by two-dimensional graphic patterns and icons. The language is used to test the feasibility of keyboardless programming, Currently the language is implemented on the Apple Macintosh personal computer. In this paper we will present, first, the Show and Tell language primitives, then simple database applications through examples, and finally the representation of the five basic operations in relational algebra; difference, union, Cartesian product, projection, and selection; all using the Show and Tell visual constructs. This demonstrates that STL is a visual relational data query language which is complete in the sense of Codd

Determinacy of Hierarchical Dataflow Model

A parallel computation model suitable for icon based visual programming languages is proposed. The model is uses to design a functional programming language for school children. A computation is specified by boxes and arrows forming a partially ordered set of nested boxes. Loops and Boolean data tokens are eliminated from the traditional dataflow model. Block structures are logical consistency (exception) are added. A declarative semantics of the model is defined formally. Using the formalism it is proved that the model is determinate

Hyperflow: A Visual Programming Language for Pen Computers

This paper presents the design philosophy of the Hyperflow visual programming language. It also gives an overview of its semantic model. The primary purpose of language is to provide a user interface for a pen-based multimedia computer system designed for school children. Yet it is versatile enough to be used as a system programming language. The concept of visually interactive process, vip in short, is introduced as the fundamental element of the semantics. Vips communicate with each other through exchange of signals, either discrete or continuous. Each vip communicates with the user through its own interface box by displaying on the box information about the vip and by receiving information pen-scribed on the box. There are four different communication modes: mailing, posting, channeling, and broadcasting. Mailing and posting are for discrete signals and channeling and broadcasting are for continuous signals. Simple Hyperflow programs are given for the purpose of illustration, including a Hyperflow specification for the Line-Clock device driver

Hierarchical Dataflow Model: A Computation Model for School Children

A new computation model suitable for icon based programming languages is proposed. The model is used to design a programming language for school children on the Macintosh personal computer. The model consists of boxes and arrows forming a partially ordered set of nested boxes. Loops and Boolean data tokens are eliminated from the traditional dataflow model. Block structures and logical consistency (exception) are added. Using a formal definition of the model it is proved that the model is determinate

Back Propagation with Integer Arithmetic

The present work investigates the significance of arithmetic precision in neural network simulation. Noting that a biological brain consists of a large number of cells of low precision, we try to answer the question: With a fixed size of memory and CPU cycles available for simulation, does a larger sized net with less precision perform better than smaller sized one with higher precision? We evaluate the merits and demerits of using low precision integer arithmetic in simulating backpropagation networks. Two identical backpropagation simulators, ibp and fbp, were constructed on Mac II, ibp with 16 bits integer representations of network parameters such as activation values, back-errors, and weights; and fbp with 96 bits floating point representations of the same parameters. The performance of the two stimulators are compared in solving the same Boolean mapping problem, the sine transfer function with eight binary inputs and one analog output. The speed-up ratio from fbp to ibp is a single training cycle in approximately 7.3 for smaller networks and 4.2 for larger ones. However, for total time necessary to obtain a solution net, the speed-up ratio is 163 for the smaller nets, and 121 for the larger nets, because ibp requires much less number of training cycles than fbp. We also found that networks trained by integer arithmetic have more generalization capabilities than those trained by floating point arithmetic. At present time we have no explanation on this matter

Memory Capacity of a Neural Network

We propose to measure the memory capacity of a state machine by the numbers of discernible states, where two states are defined to be discernible if the machine manifests the identical input-output mapping in both states. According to the definition, a neuron network of n\u3e0 inputs and one output, with an uncountable set of internal states, has the memory capacity of log2TF(n), where TF(n) is the number of different Boolean functions the network can realize with different synaptic weight and threshold values. It is shown that such a network with k\u3e0 linear threshold units can realize at most 2k(n2+k2) Boolean functions and therefore the network has memory capacity of at most k(n2+k2) bits or 2k3 bits when

Transaction Network: A Parallel Computation Model based on Consume/Produce Paradigm

This report introduces a new parallel computation model that is suitable for pursuit of large scale concurrency. Our goal is to develop a semantically clean paradigm for distributed computation with fine-grained parallelism. Our approach is to demote the notion of process as the key concept in organizing large scale parallel computation. We promote, instead, the notion of transaction, an anonymous atomic action void of internal state, as the basic element of computation. We propose to organize a computation as a network, called a transaction net, of databases connected by transactions. A transaction, when it is fired, consumes data objects from source databases and produces data objects in target databases as an atomic action. A transaction net is akin to a Petrich net, where the token, the place, and the transition corresponds to the data, the database and the transaction, respectively. The state of computation is represented by the data state without the control state. An informal definition of the model is given, and solutions for well known programming problems such as sorting, transitive closure, Hamiltonean circuit, shortest path, and the eight queen\u27s problem

Show and Tell User\u27s Manual

The purpose of this report is to introduce essential features of the Show and Tell Language system to those computer users who are already familiar with some high-level programming language such as FORTRAN, BASIC or PASCAL. This manual is not intended for school children. Some familiarity with the Macintosh user interface and the MacPaint application program is assumed. It is also assumed that the Show and Tell application program disk and the Sample program are available to the reader. The basic programming concepts in Show and Tell are introduced in Chapter Three. The reader may find it easer to start with Chapter Three, then come back to Chapter One and Chapter Two

A Comparison Study of The Pen and The Mouse in Editing Graphic Diagrams

We report the results of an experiment comparing the merits of the pen and the mouse as drawing devices. For this study a pen-based graphic diagram editor equipped with a shape recognition algorithm was developed on GO\u27s PenPoint operating system. A commercially available drawing program on NeXT was used for mouse-based editing. Twelve CS students were chosen as subjects and asked to draw four different diagrams of similar complexity: two with a pen and the other two with a mouse. The diagrams are chosen from the categories of dataflow visual language, Petri nets, flowcharts, and state diagrams. The results indicate that drawing by pen is twice as fast as drawing by mouse