Jongwhoa Na

The blind interactive guide system using RFID-Based indoor positioning system

In this paper, we designed and implemented the Blind Interactive Guide System (BIGS) for the blind person to use in the building. The BIGS uses RFID-based indoor positioning system to acquire the current location information of the user. The system consists of two parts: the smart floor and the portable terminal unit. The smart floor is a floor of a building where each tile of the floor has the passive RFID tag which transmits a unique ID number. The portable terminal unit is an embedded system equipped with an RFID reader as an input device so that the BIGS can get the current location information of the user. Using the preinstalled map of the target floor, the blind person can navigate to the final destination. The prototype is implemented and successfully operated

A Novel Simulation Fault Injection Method for Dependability Analysis

Presilicon testing and verification is a crucial step in qualifying the RTL for the subsequent implementation phases. This article presents a novel simulation-based fault injection methodology that is applied at the system description level, as opposed to the lower, flattened RT level, in order to reduce simulation time.

A Novel Simulation Fault Injection using Electronic Systems Level Simulation Models

Abstract—In this paper, we propose a novel simulation fault injection method for the dependability analysis of complex SoCs using 32 nm technology. In previous simulation fault injections, the original simulation model is modified to implement a saboteur module or many mutants. This creates a problem since the architectural complexity of current SoCs is expected to increase rapidly in the 32 nm era. Furthermore, the modification process may incur additional tasks, such as verification and validation of the modified simulation model. Our simulation fault injection environment uses the modified SystemC simulation kernel augmented for fault injection experiments. The proposed methodology offers the following advantages over previous simulation fault injection methods. First, it does not require changes in the target simulation design model. Second, it minimizes the simulation hardware resource requirements and simulation time. Third, it allows mixed simulation of the ESL model and the register transfer level model using wrappers. To demonstrate the effectiveness of the proposed methodology, we designed the SystemC models of MIPS and TMR MIPS processors and ran the benchmark SW from MiBench to compare the failure rates of the two processors.

Simple and Low-Cost Heartbeat-Based Dual Modular Redundant Systems for Wireless Sensor Networks

Sensor node lifetimes have become a critical issue in the operation of wireless sensor networks (WSNs). The redundancy technique can improve the reliability and availability of WSN sensor nodes. However, augmenting sensor nodes with a redundancy mechanism increases the cost and performance of the system. In this paper, to improve sensor node reliability without increasing costs, we investigate three dual modular redundancy systems using low-cost hardware and a heartbeat mechanism with a UART and direct UDP channels. The proposed systems exhibit three advantages – low latency, cost-effectiveness, and easy configuration. We find that the average failover time for our DMR implementation using the direct UDP connection is 379 ms.

Simulation-Based Reliability Improvement Factor for Safety-Critical Embedded Systems

In the design of safety-critical embedded systems (SCES), the use of reliability measures is crucial to identify reliability-optimized and cost-optimized fault-tolerant mechanisms (FTM). The reliability improvement factor (RIF) was used in this study, which is a ratio of the probability of failure of the baseline system to that of the redundant system for a fixed mission time. We extend the analytical RIF into the simulation-based RIF (SRIF), as a relative measure of the reliability improvement for the FTM of SCES. We calculated the SRIF of the FTM by substituting the failure rate, which can be obtained from the statistical fault injection simulation by using co-simulation models and representative fault models. We use SRIF to compare the performance of FTMs and find the most reliable FTM. As a case study, we compare the SRIF of the dual-modular redundant (DMR) FTM with the triple-modular redundant (TMR) using ARM7 SystemC simulation models.

Applicability of No-Hands Computer Input Devices for the Certificates for Microsoft Office Software

The workload-based evaluation is applied for the certificates of the Microsoft Office Specialist. The certificates may be one of the solutions for this conflicts cause by the misunderstanding between the employer and the employee. We analyzed the MOS Word test questions by using various types of input devices including the camera mouse and the no-hands mouse. The experimental result showed the no-hands input devices can be successfully utilized for the examination for the MOS certificates.

Design of the Multimodal Input System using Image Processing and Speech Recognition

Recently, various types of camera mouse are developed using the image processing. The camera mouse showed limited performance compared to the traditional optical mouse in terms of the response time and the usability. These problems are caused by the mismatch between the size of the monitor and that of the active pixel area of the CMOS Image Sensor. To overcome these limitations, we designed a new input device that uses the face recognition as well as the speech recognition simultaneously. In the proposed system, the area of the monitor is partitioned into `n` zones. The face recognition is performed using the web-camera, so that the mouse pointer follows the movement of the face of the user in a particular zone. The user can switch the zone by speaking the name of the zone. The multimodal mouse is analyzed using the Keystroke Level Model and the initial experiments was performed to evaluate the feasibility and the performance of the proposed system.