Journal of
Systemics, Cybernetics and Informatics
HOME  |   CURRENT ISSUE   |   PAST ISSUES   |   RELATED PUBLICATIONS     IIIS   |   SEARCH     CONTACT US
 

 ISSN: 1690-4524 (Online)



TABLE OF CONTENTS





A Closed-Form Approximation Solution for an Inventory Model with Supply Disruptions and Non-ZIO Reorder Policy
David Heimann, Frenck Waage
Pages: 1-12
Abstract | Full Text
ABSTRACT:
In supply chains, domestic and global, a producer must decide on an optimal quantity of items to order from suppliers and at what inventory level to place this order (the EOQ problem). We discuss how to modify the EOQ in the face of failures and recoveries by the supplier. This is the EOQ with disruption problem (EOQD). The supplier makes transitions between being capable and not being capable of filling an order in a Markov failure and recovery process. The producer adjusts the reorder point and the inventories to provide a margin of safety. Numerical solutions to the EOQD problem have been developed. In addition, a closed-form approximate solution has been developed for the zero inventory option (ZIO), where the inventory level on reordering is set to be zero. This paper develops a closed-form approximate solution for the EOQD problem when the reorder point can be non-zero, obtaining for that situation an optimal reorder quantity and optimal reorder point that represents an improvement on the optimal ZIO solution. The paper also supplies numerical examples demonstrating the cost savings against the ZIO situation, as well as the accuracy of the approximation technique.


Multi-Sensory Cognitive Learning as Facilitated in a Multimedia Tutorial for Item Response Theory
Chong Ho Yu, Samuel DiGangi, Angel Jannasch-Pennell, Victoria Stay, Wen-juo Lo, Zeynep Kilic
Pages: 13-22
Abstract | Full Text
ABSTRACT:
The objective of this paper is to introduce an application of multi-sensory cognitive learning theory into the development of a multimedia tutorial for Item Response Theory. The cognitive multimedia theory suggests that the visual and auditory material should be presented simultaneously to reinforce the retention of learned materials. A computer-assisted module is carefully designed based upon the preceding theory and also an experiment was conducted to examine the effect of audio types (human audio, computer audio, and no audio) on learner performance measured by an objective test. It was found that while there is no significant performance gap between the human audio and the no audio group, the two groups substantively outperform the computer audio group. A plausible explanation is that un-natural audio requires additional cognitive power to process the information and thus this distraction affects the performance.


Performance Factors Impacting Web-Based Learning Support Systems
Qidong Cao, Yingjin Cui, Xue Bai
Pages: 23-26
Abstract | Full Text
ABSTRACT:
Web-based course management systems have been overwhelmingly accepted by instructors, students, and educational institutions. In order to improve quality of existing systems, the questions must be answered are what underlying dimensions of user’s satisfaction exist and on which of those dimensions we should apply the resources. In this study, the principal component analysis was undertaken to determine the underlying dimensions. Then the scores for each dimension were calculated, and bivariate correlations between the dimensions and the user’s satisfaction were used to assess the marginal importance of each dimension in improving web course management systems. In addition, the survey instrument was tested for reliability and validity.


Experimental and Theoretical Analysis of Storage Friendly TCP Performance in Distributed Storage Area Network
Suresh Muknahallipatna, Gayathri Sivasankaran, Joseph Miles, Timothy Brothers, Nagapramod Mandagere, Joseph L. White, Howard Johnson
Pages: 27-33
Abstract | Full Text
ABSTRACT:
Fibre channel storage area networks (SAN) are widely implemented in production data center environments. Recently the storage industry has moved towards deployment of distributed SANs (DSAN), geographically dispersed across large physical distances. In a DSAN, specialized gateway devices interconnect the individual Fibre Channel (FC) fabrics over IP networks using TCP/IP based protocols (iFCP or FCIP) or over metro to long distance optical networks such as Dense Wavelength Division Multiplexing (DWDM) based networks that utilize native FC ports supporting large numbers of link credits. When using TCP/IP based storage networking protocols to interconnect local FC fabrics in a DSAN, the sustained throughput achievable depends upon the link characteristics and TCP/IP stack implementation. Sustaining maximum possible storage traffic throughput across the wide area network enables practical DSAN deployments by maintaining the required site to site service level agreements.
This study explores the effects of several TCP/IP modifications on sustained traffic throughput for a DSAN interconnected via iFCP gateways across an impaired network. The TCP/IP stack modifications, known as storage friendly, include changes to the window scaling, congestion avoidance, and fast recovery algorithms. The theoretical background and experimental results are presented to explain and illustrate these modifications.


Virtual Property Manager: Providing a Simulated Learning Environment in a New University Program of Study
Andrew Carswell, Russell James
Pages: 34-40
Abstract | Full Text
ABSTRACT:
This paper relates the experience that students have while accessing Virtual Property Manager (VPM), a Web-based simulation learning tool designed to introduce students to a new discipline being offered at the university – Residential Property Management. The VPM simulation was designed in part to develop student interest in the new program. Results indicate that this simple simulation device did make a notable impact on student interest. Additionally, student acceptance and self-reported impact differed significantly based upon the delivery context. Adding a competitive reward element to the simulation experience improved student’s evaluation of the software and self-reported interest in the field. Results indicate that educational simulation evaluation, acceptance, and performance may often be substantially influenced by the delivery context, rather than simply the program itself. Developers may do well to focus “outside the box” of program content to promote audience-specific delivery environments.


A General Combinatorial Ant System-based Distributed Routing Algorithm for Communication Networks
Jose Aguilar, Miguel Labrador
Pages: 41-49
Abstract | Full Text
ABSTRACT:
In this paper, a general Combinatorial Ant System-based distributed routing algorithm modeled like a dynamic combinatorial optimization problem is presented. In the proposed algorithm, the solution space of the dynamic combinatorial optimization problem is mapped into the space where the ants will walk, and the transition probability and the pheromone update formula of the Ant System is defined according to the objective function of the communication problem. The general nature of the approach allows for the optimization of the routing function to be applied in different types of networks just changing the performance criteria to be optimized. In fact, we test and compare the performance of our routing algorithm against well-known routing schemes for wired and wireless networks, and show its superior performance in terms throughput, delay and energy efficiency.



Information and Communication Technology (ICT) Literacy: Integration and Assessment in Higher Education
Irvin R. Katz, Alexius Smith Macklin
Pages: 50-55
Abstract | Full Text
ABSTRACT:
Despite coming of age with the Internet and other technology, many college students lack the information and communication technology (ICT) literacy skills—--locating, evaluating, and communicating information—--necessary to navigate and use the overabundance of information available today. This paper presents a study of the validity of a simulations-based assessment of ICT literacy skills. Our overall goals for the assessment are to support ICT literacy instructional initiatives at colleges and universities.


Diverse Strategies for Diverse Learners: Action Learning in a Hybrid Mode
Esmarie Strydom, Gail Janse van Rensburg
Pages: 56-63
Abstract | Full Text
ABSTRACT:
This paper describes an action research study during which a flexible or hybrid approach to delivering an Information and Communication Technology competency course is implemented in the preparation of student teachers. The course incorporates Web-based course-content delivery, face-to-face classroom meetings to satisfy the need for human interaction, a variety of assessment methods, as well as recognition of prior learning. The objectives are to accommodate learning diversity, make learning focused and achievable for each learner, allow for intervention if the learning outcomes are not met, and focus on and guide the learning process, i.e. teach learners how to learn. This paper reports on the perspectives and experiences of two groups of first year learners, namely student teachers who attended a hybrid ICT course and first year learners who attended an e-learning ICT course. It was found that the success rate of the hybrid mode ICT course was significantly higher than that of the similar e-learning ICT course. The hybrid mode ICT course also enabled the learners to become self-directed to a higher degree.


Semantic Web for Chemical Genomics – need, how to, and hurdles
Talapady Bhat
Pages: 64-69
Abstract | Full Text
ABSTRACT:
Semantic Web has been often suggested as the information technology solution to the growing problem in managing the millions of data points generated by modern science such as nanotechnology and high through-put screening for drugs. However, the progress towards this vision envisaged by the W3C has been very limited. Here we discuss –some of the obstacles to the realization of this vision and we make some suggestions as to how one may overcome some of these hurdles? Here we discuss some of these issues and present thoughts on an alternative method to Semantic Web that is less drastic in requirements. This method does not require the use of RDF and Protege, and it works in an environment currently used by the chemical and biological database providers. In our method one attempts to use as many components as possible from the tools already used by the database providers and one brings in far fewer new tools and techniques compared to the method that use RDF or Protégé. Our method uses a standard database environment and web tools rather than the RDF and Protégé to manage user interface and the data is held in a database rather than using RDF. This method shifts the task of building Semantic knowledge-base and ontology from RDF and Protégé to a SQL based database environment.


Cost Analysis for Real-time Java Scoped-memory Areas
Delvin Defoe, Rob LeGrand, Ron Cytron
Pages: 70-77
Abstract | Full Text
ABSTRACT:
Java has recently joined C and C++ as a development platform for real-time and embedded applications. Java’s garbage collection, while generally a useful feature, can be problematic for these applications: garbage collection occurs at unpredictable times and its latency is typically unbounded. This can compromise necessary real-time guarantees. To overcome these limitations, the Real-Time for Java Expert Group (RTJEG) proposed the Real-Time Specification for Java (RTSJ), which introduced new memory models and new threads to utilize those models. One such memory model uses scoped-memory areas, which work best in the context of a NoHeapRealtimeThread (NHRT). Although much work has been done with scoped-memory areas and NHRTs, there is no system-independent analysis of their costs. In this article we present an asymptotic analysis for RTSJ scoped-memory areas and NHRTs.


Randomness-Based Scale-Chromatic Image Analysis for Interactive Mapping on Satellite-Roadway-Vehicle Network
Kohji Kamejima
Pages: 78-86
Abstract | Full Text
ABSTRACT:
A new framework is presented for integrating satellite/avionics sensors with onboard vision to support information intensive maneuvering. Real time bindings of the bird's eye observation and the driver's view via GPS provides \textit{as-is} basis for perception and decision. Randomness-based roadway pattern model is implemented by fractal coding scheme associating bird's eye and frontal views. The feasibility of the framework with resquirements for vison system is discussed through concept modeling and experimental studies.