Transactional Model of a Company based on the Hub-Spoke and LDPC/MIMO Models J. P. TORRES (1) I. SOTO (1) R. CARRASCO (2) (1) Industrial Engineering Department Engineering Faculty Universidad de Santiago de Chile Av. Ecuador 3769, Santiago CHILE isoto@lauca.usach.cl (2) School of Electrical, Electronic and Computer Engineering. University of Newcastle upon Tyne Merz Court Newcastle upon Tyne (NE1 7RU) UNITED KINGDOM Abstract— This paper offers a description of a new transactional model designed for a m-commerce 4G architecture, and the economic benefit that it can bring to an organization. For the design, it has been used a Hub and Spoke transport model for the material flow, a Queuing model for the bank company transactions flow, and a LDPC/MIMO channel for the transmission environment. With the new system, the SNR can be reduced approximately in 8 dB, which makes possible a greater rapidity in the transactions. The global results show an economic gain of at least a 20.12%, because of the redesign of the conversations, the optimization of the Transport Problem using the Hub and Spoke Model and the reduction in the errors of the sent data. Keywords— Transaction, Conversation, MIMO (Multiple- Input, Multiple-Output) channel, LDPC (Low-Density Parity- Check), Hub and Spoke Model and Optimization 1. Introduction The motivation of this paper is to evaluate a design of a new transactional model to implement the 4G technology, and also to evaluate the economic impact. In the literature most of the 4G designs fall in technical details without any concern related with implementation issues and the optimization of the channel is made only from the physical architecture, codification codes, modulation codes and channel code. In reference [1] B. Yeah and L. Hanzo explained a reduced-complexity turbo detector for convolutional-coding aided space-time trellis coded (STTC) schemes from the technical point of view only. On the other hand, the economic evaluation of a new technology in the companies have restrictions about equipment, training of personnel, legal restrictions and other related to the organization [2]. Other restrictions are not evaluated, like those ones caused by the way of communication, for example, a lost of signal that increases the time of communication of the call, increasing then the total time of the transaction (accumulated sum of conversation timing of the transaction cycle). This kind of disturbances is despised because the cost associated to them is low and difficult to quantify. From the m-commerce point of view, in the literature are found some designs and evaluations of applications[3]. In these designs the economic transactions are repeated as one of the main dimensions, which is logical because the investigated issue is trade. The problem is that they do not approach other important dimensions as conversations (information flows) that allow to make contracts, the environment through these regular communications are made, and the transport structure in which physical goods are exchanged. This paper analyzes the problem to minimize the total costs of shipment considering the own restrictions of the channel by which the transaction is made, improving the four mentioned dimensions, named generically as: physical structure, conversational structure, channel structure and economic transactions structure. To make this economic evaluation, different methods have been used in order to analyse each structure, such as System Dynamics [4], Linear Programming and transaction process using Workflow. In fact, the material flows problem was modelled using a transportation model and the 4G conversations were modelled using Workflow inspired by Medina and Flores model to make an organizational design, supposing that the business Proceedings of the 6th WSEAS International Conference on Applied Computer Science, Hangzhou, China, April 15-17, 2007 576