Ching-Su Chang

Development of a Portable Linux-Based ECG Measurement and Monitoring System

This work presents a portable Linux-based electrocardiogram (ECG) signals measurement and monitoring system. The proposed system consists of an ECG front end and an embedded Linux platform (ELP). The ECG front end digitizes 12-lead ECG signals acquired from electrodes and then delivers them to the ELP via a universal serial bus (USB) interface for storage, signal processing, and graphic display. The proposed system can be installed anywhere (e.g., offices, homes, healthcare centers and ambulances) to allow people to self-monitor their health conditions at any time. The proposed system also enables remote diagnosis via Internet. Additionally, the system has a 7-in. interactive TFT-LCD touch screen that enables users to execute various functions, such as scaling a single-lead or multiple-lead ECG waveforms. The effectiveness of the proposed system was verified by using a commercial 12-lead ECG signal simulator and in vivo experiments. In addition to its portability, the proposed system is license-free as Linux, an open-source code, is utilized during software development. The cost-effectiveness of the system significantly enhances its practical application for personal healthcare.

Development and evaluation of an RFID-based e-restaurant system for customer-centric service

Traditional restaurant service is passive: waiters must interact with customers directly before processing their orders. However, a high quality customer-centered service system would actively identity customers, their favorite meals and their expenditure records. To achieve this goal, this study integrates radio frequency identification (RFID), wireless local area network (WLAN) and database technologies to develop an e-restaurant system for customer-centric service, which enables waiters to immediately identify customers via RFID-based membership cards and then actively provide customized services. The user interface of the proposed system is built with Visual C# 2005 and eMbedded Visual C++, and the database is built on Microsoft SQL Server 2005 for Server management and statistic reporting. The WLAN and RFID technologies are used to transmit real-time information of each dining table. To verify the effectiveness of the proposed system, a series of experiments was conducted in two restaurants. A questionnaire survey administrated to waiters and customers confirmed the effectiveness of the proposed e-restaurant system in providing customer-centric service. Furthermore, extensive interviews with restaurant owners revealed very positive feedback.

Developing an Intelligent e-Restaurant With a Menu Recommender for Customer-Centric Service

Traditional restaurant service is typically passive: Waiters must interact with customers directly before processing their orders. However, a high-quality service system should be customer centered; it should immediately recognize customer identities, favorite menus, and expenditure records to provide customer-centric services. To achieve this goal, this study integrates radio frequency identification (RFID), wireless local area network, database technologies, and a menu recommender to develop an intelligent e-restaurant for customer-centric service. This system enables waiters to immediately identify customers via RFID-based membership cards and then actively recommend the most appropriate menus through menu recommender for customers. Experimental results that are obtained from a case study conducted in two Taipei restaurants indicate that the proposed system has practical potential in providing customer-centric service.

Development and implementation of an e-restaurant for customer-centric service using WLAN and RFID technologies

Traditional restaurants only provide passive service where waiter can only deal with customers order by asking customers need and then waits for answer. However, a high quality service system should be customer-centered, i.e., customers identity and therefore his/her favorite meals and expenditure records in past days can be immediately recognized by service system so as to provide customer-centric services. To achieve this goal, this study integrates RFID and wireless local area network (WLAN) technologies to implement an e-restaurant for customer-centric service, which enables waiters to immediately identify each customer via his/her own RFID-based membership card and then actively provides customized services. The user interface of the proposed system is built with Visual C# 2005 and eMbedded Visual C++, and the database is built on Microsoft SQL Server 2005 for server management and statistic reporting. WLAN and RFID are used to transmit the real-time information of each dining table. Experimental result reveals that the proposed system has potential for practical application.

Ubiquitous Emergency Medical Service System Based on Wireless Biosensors, Traffic Information, and Wireless Communication Technologies: Development and Evaluation

This study presents a new ubiquitous emergency medical service system (UEMS) that consists of a ubiquitous tele-diagnosis interface and a traffic guiding subsystem. The UEMS addresses unresolved issues of emergency medical services by managing the sensor wires for eliminating inconvenience for both patients and paramedics in an ambulance, providing ubiquitous accessibility of patients’ biosignals in remote areas where the ambulance cannot arrive directly, and offering availability of real-time traffic information which can make the ambulance reach the destination within the shortest time. In the proposed system, patient’s biosignals and real-time video, acquired by wireless biosensors and a webcam, can be simultaneously transmitted to an emergency room for pre-hospital treatment via WiMax/3.5 G networks. Performances of WiMax and 3.5 G, in terms of initialization time, data rate, and average end-to-end delay are evaluated and compared. A driver can choose the route of the shortest time among the suggested routes by Google Maps after inspecting the current traffic conditions based on real-time CCTV camera streams and traffic information. The destination address can be inputted vocally for easiness and safety in driving. A series of field test results validates the feasibility of the proposed system for application in real-life scenarios.

PC-based ECG signal analysis using artificial neural network

This study develops a real-time personal computer-based (PC-based) ECG signal measurement and monitoring system to allow PC users to monitor their health status at any time. The system includes a signal processing unit and a health evaluation unit. The signal processing unit consists of a front-end ECG signal amplification circuit, electrocardiogram (ECG) signal acquisition circuit, USB power supply circuit and a control circuit. The second unit is a software tool developed on a PC for evaluating userpsilas health based on heart rate variability (HRV) data. A back-propagation neural network is trained by using the features of HRV message to classify ECG signals for further diagnosis via telemedicine. Experimental results indicate that the proposed system has practical potential in health monitoring and evaluation for PC users.

Development of a ubiquitous emergency medical service system based on zigbee and 3.5g wireless communication technologies

This study builds a ubiquitous emergency medical service (EMS) system with sensor devices, a smartphone, a webcam, Zigbee, and a 3.5G wireless network. To avoid excessive wiring, a Zigbee-based wireless sensor network within the ambulance records the patients biosignals, which includes an electrocardiogram (ECG), pulse, blood oxygen content, and temperature. Those biosignals are then transmitted to the Server located in the hospital emergency room via 3.5G wireless network for immediate first-aid preparation. This process significantly enhances EMS quality. Our experiment demonstrates biosignal transmission in real time for EMS application. In the future, we will promote the proposed system to WiMAX network when it becomes more pervasive in Taiwan to offer a much higher data throughput.

Enhancing Bluetooth data throughput using a mode/packet switching scheme based on ARQN statistics

Though many Bluetooth ACL packet types have been presented to satisfy various requirements, only one fixed packet type is used during the whole transmission period in the Bluetooth products. Therefore, the Bluetooth system will not yield the maximum data throughput since it cannot adapt the transmit packets to the dynamic channel conditions. To overcome this difficulty, a simple mode/packet switching scheme based on Bluetooth ARQN statistics is proposed in this paper. The results of simulation experiments carried out over AWGN and Rayleigh fading channels indicate that the proposed scheme can effectively track channel variations to switch operation mode and transmit packet and thereby significantly increases Bluetooth data throughput.

Markov Model Parameters Optimization for Asynchronous Impulsive Noise over Power Line Communication Network

The asynchronous impulsive noise is one of the most crucial factors that degrade the performance of power line communication (PLC) network. Several approaches have been presented to characterize the time domain behavior of the asynchronous impulsive noise over the PLC network. Among them a partitioned Markov-chains model has been validated with measured data. However, its model parameters estimation using the Simplex method can easily trap the final solution into the local optimum. To overcome this difficulty, a new estimation scheme based on the genetic algorithm (GA) is proposed in this paper. Experimental results show that the proposed scheme yields estimates which more closely match the experimental data statistics.

Development of an emergency medical service system based on wireless networks and real-time traffic information

This study develops a real-time traffic information-based emergency medical service (RTIEMS) system by employing sensor devices, webcam, 2.4 GHz ISM band RF module, ZigBee, GPS, Google Maps, and WiMAX mobile network. In the ambulance, patient biosignals consisting of electrocardiogram (ECG), temperature, oxygen, and pulse can be wirelessly transmitted to the in-car gateway. Then, together with patient real-time video, those biosignals are transmitted via WiMAX mobile network to the server located in the hospital emergency room for immediate first-aid preparation. Furthermore, to avoid jam-packed areas, a traffic guiding subsystem is presented based on the WebGIS that consists of Google Maps and GPS to help patient be delivered to the hospital with shortest time. Experimental results verify the effectiveness of the proposed RTIEMS system in lengthening the golden rescue time; thus significantly enhancing service quality of emergency medical system.