Shih-Che Lo

A zero-watermark scheme with geometrical invariants using SVM and PSO against geometrical attacks for image protection

Highlights? A zero-watermark scheme is proposed using RST invariant features, the SVM and the PSO algorithm against RST attacks for image authentication. ? The SVM-based zero-watermark scheme makes no changes to original images after embedding the owner signature of images. ? The SVM-based zero-watermark scheme requires no original image while retrieving watermarks. ? The particle swarm optimization algorithm is employed to search for a set of nearly optimal parameters of the SVM. ? In average, the SVM-based zero-watermark scheme outperforms other existing methods against RST attacks. This paper proposes a zero-watermark scheme with geometrical invariants using support vector machine (SVM) classifier against geometrical attacks for image authentication. Here geometrical attacks merely address rotation, scale, and translation (RST) operations on images. The proposed scheme is called the SVM-based zero-watermark (SZW) scheme hereafter. The SZW method makes no changes to original images while embedding the owner signature of images so as to achieve high transparency. Moreover, in order to promote the robustness to RST operations, it integrates the discrete Fourier transform (DFT) with the log-polar mapping (LPM) for finding out RST invariants of images. The SZW method then generates the secret key for a host image via performing a logical operation exclusive disjunction, an exclusive-or (XOR) operation, on the original watermark and a set of the characteristics of the RST invariants of the host image. Subsequently, a trained SVM (TSVM) is regarded as a mapping so that it can memorize the relationships between the set of characteristics of RST invariants and the secret key. During the watermark-extraction process of the SZW method, the TSVM is first fed with the set of characteristics of RST invariants of the watermarked image to get the estimated secret key. The SZW method then extracts the estimated watermark by performing the XOR operation on the set of characteristics of RST invariants and the estimated secret key. Consequently, the SZW method requires no original image while retrieving watermarks. In the paper, the particle swarm optimization (PSO) algorithm is also employed to search for a set of nearly optimal parameters of the SVM. Finally, the experimental results show that, in average, the SZW method outperforms other existing methods against RST attacks under consideration here.

Design of real-time fuzzy bus holding system for the mass rapid transit transfer system

In this research, we aim to design real-time fuzzy bus holding system (FBHS) for the mass rapid transit (MRT) transfer system with real-time information for a terminal station with in a metropolitan area. We employ fuzzy logic to develop a model for the MRT-bus system to achieve the following goals pertaining to bus holding strategies used: to reduce the bus waiting time, to reduce the passenger waiting time, and to reduce passenger traveling time. In order to enhance the performance of the MRT-bus transfer system, we develop several fuzzy rules in the transfer models that are different functions of the travel time taken by buses during different time periods, such as rush hours and off-peak hours. Real-time traffic information acquired by the intelligent transportation systems through global positioning systems is used as input data for the FBHS. A performance index function is derived and served as the performance measure to compare our system with real data. The experimental results show that the FBHS significantly reduces the overall passenger waiting time and improves the performance of the MRT-bus transfer system.

Solving multi-criteria supplier segmentation based on the modified FAHP for supply chain management: a case study

The multi-criteria supplier segmentation (MSS) has become one of the most important problems and plays a key role in every global company. It is vital for every company to successfully select suppliers, to undertake selection evaluation process for a long time, and to invest enormous of capital and effort to manage supply chain efficiently. This study aims to propose a new fuzzy analytic hierarchy process (FAHP) method for the efficiency evaluation of suppliers with bell-shaped membership functions. Since the MSS is a multi-criteria decision-making problem, we decomposed the problem into two main clusters grouping criteria, including the criterion of capability and the criterion of willingness in the first phase. Then the modified FAHP method is applied to acquire a ranking of the candidate suppliers in the second phase with evaluation of different alternatives. A study from the case company was conducted to choose the best solution alternative(s) for the case company. From the experiments, we show that the proposed method is a very practical and efficient technique for the decision makers to select best options for the MSS in managing supply chain.

The design of real-time logistics information system for trucking industry

A critical link in the overnight Express Package services is the on-time arrival of trucks at local airport terminals. Truck delays can delay the package sorting process, which can in turn delay aircraft departures from the local terminal, as well as aircraft departures from hub terminals that depend on timely aircraft arrivals. In this paper, the design of a real-time logistics information system (RLIS) for trucking industry was addressed, considering the effects of traffic congestion during rush hour. Two types of forecasting methods, time series models and nonlinear fuzzy reasoning, were created and embedded into the RLIS. The results from practical web services reveal a substantial improvement of the truck scheduling performance and help decision makers determine schedule coordination between ground transportation and aircraft departures at airport cargo terminals.

The Design of a Quality Control System of PCB with SMT Based on RFID and AOI

This research combines Radio Frequency Identification (RFID) and computer vision technology to assist printable circuit board (PCB) production line with quality control management. The proposed system relies on RFID tags offering ubiquitous computing for information delivery. It provides functions of management and checkpoints for production steps confirmation from beginning to the end coping with instant information flow. PCB allocation and Surface Mount Device assembly were also considered for real-time production ability and maintenance with instant information for management and decision support system. Automatic Optical Inspection system in the last step with neural network model combining with image detection technology provides the quality control component in the system. Experiments results show the effective quality control system with RFID embedded in the production line for assembling PCB with Surface Mount Technology.

The simulation of MRT transfer system based on bus holding strategies with platform constraints

This research aims at the bus holding strategies for the simulation of Mass Rapid Transit (MRT) transferring system in a terminal station with platform constraints for bus in the metropolitan area. We developed and evaluated the transfer system through computer simulation models for MRT with bus system that the goals of bus holding strategies in the model were: reduce bus waiting time, reduce passengers waiting time for the bus, and reduce passengers traveling time. In order to enhance the performance of the MRT-Bus transfer system, we develop several bus holding strategies scenarios that use different traveling time functions of buses at different time intervals, such as rush hours and off-peak hours, with bus platform capacity constraints in the transfer models to construct proposed transfer models in the MRT transfer system. Real-time traffic information acquired by the Intelligent Transportation Systems (ITS) through Global Positioning System (GPS) provided input data for the simulation models. Performance index function were derived and served as performance measure to compare different bus holding strategies.