Browsing by Author "Liu, Xiaolong"

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A Complete System for Analysis of Video Lecture Based on Eye Tracking
(2018-01-01)
Zhang, Xuebai
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Yuan, Shyan-Ming
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Chen, Ming-Dao
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Liu, Xiaolong
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資訊工程學系
An eye tracking technology provides a faster and more intuitive interface to explore the learner psychology. In this paper, with the aim of assisting researcher to expand the knowledge of video lectures, we present an efficient system named VLEYE based on eye tracking. The system allows gathering the dynamic areas of interest (AOIs) and combining them with eye movement data. There are mainly three modules in the proposed system, including "eye movement recorder," "dynamic AOI module," and "video analyzer." The "eye movement recorder" records the eye movement data by eye tracking device, where mouse cursor control function is applied to support the use of low-cost devices. The AOIs could be drawn manually or detected and tracked by the provided algorithm automatically in the "dynamic AOI module." The "video analyzer" provides various visualization modes to view and compare the eye movement information for single or multiple subject, as well as statistical charts and detail fixation information. In addition to performance testing, a case study was conducted to verify the applicability of the proposed system. We demonstrate that this system works well and is an essential step forward in efficiently helping studies to better understand learner cognitive processes for dynamic stimuli within video.
Automated Testing Framework for Geographical Distributed Testing Environment
(2019-01-01)
Liu, Xiaolong
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Juan, Apua
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Chen, Riqing
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Yuan, Shyan-Ming
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資訊工程學系
Automated testing is critical for the complex products development and manufacture. In generally, connecting multiple test environments in geographical distributed environment to share resources is a way to reduce cost. However, it conflicts with the principle of "keep test environment clean". Moreover, high latency between geographical different networks may impact origin automated test activities in reality. In this paper, we propose an automated testing framework for geographical distributed testing environment to solve the problems of sharing resources. In the proposed framework, improved Test Harness (TH) and integrated Test as a Service (TaaS) are proposed to assure automated testing flow and guarantee test integrity. The proposed framework may not impact origin automated test activities, which could reduce the cost of test activities in really. In addition, a basic implementation of Test Harness and TaaS Console in the proposed framework are presented in this paper.
Automatic cloud service testing and bottleneck detection system with scaling recommendation
(2020-01-10)
Liu, Xiaolong
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Sheu, Ruey-Kai
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Lo, Win-Tsung
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Yuan, Shyan-Ming
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資訊工程學系
Performance problems in a cloud service are difficult to diagnose because they may be caused by various system components. This study proposes an automatic cloud service testing and bottleneck detection system that is applicable to different types of services. With the proposed test module, the user can customize test scenarios to automatically test and collect the corresponding metrics of the target service. Afterward, the proposed bottleneck detection algorithm analyzes the collected metrics and determines whether a bottleneck is presented in the target system. The bottleneck detection module also provides a scaling recommendation for the service provider to facilitate the service system reconfiguration. The experimental results reveal that the proposed system could detect a potential bottleneck in a service system accurately. In accordance with the scaling recommendation, the performance of the target cloud service can be improved efficiently after reconfiguration. Therefore, usage of the proposed system can ensure a high quality of service, and the service level objective could be fulfilled.
Cloud Resource Management With Turnaround Time Driven Auto-Scaling
(2017-01-01)
Liu, Xiaolong
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Yuan, Shyan-Ming
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Luo, Guo-Heng
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Huang, Hao-Yu
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Bellavista, Paolo
Cloud resource management research and techniques have received relevant attention in the last years. In particular, recently numerous studies have focused on determining the relationship between server side system information and performance experience for reducing resource wastage. However, the genuine experiences of clients cannot be readily understood only by using the collected server-side information. In this paper, a cloud resource management framework with two novel turnaround time driven auto-scaling mechanisms is proposed for ensuring the stability of service performance. In the first mechanism, turnaround time monitors are deployed in the client-side instead of the more traditional server-side, and the information collected outside the server is used for driving a dynamic auto-scaling operation. In the second mechanism, a schedule-based auto scaling preconfiguration maker is designed to test and identify the amount of resources required in the cloud. The reported experimental results demonstrate that using our original framework for cloud resource management, stable service quality can be ensured and, moreover, a certain amount of quality variation can be handled in order to allow the stability of the service performance to be increased.
Distributed Testing System for Web Service Based on Crowdsourcing
(2018-01-01)
Liu, Xiaolong
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Hsieh, Yun-Ju
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Chen, Riqing
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Yuan, Shyan-Ming
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資訊工程學系
To appropriately realize the performance of a web service, it is essential to give it a comprehensive testing. Although an elastic test could be guaranteed in traditional cloud testing systems, the geographical test that supports real user behavior simulation remains a problem. In this paper, we propose a testing system based on a crowdsourcing model to carry out the distributed test on a target web server automatically. The proposed crowdsourcing-based testing system (CTS) provides a reliable testing model to simulate real user web browsing behaviors with the help of web browsers scattered all around the world. In order to make the entire test process the same as the real situation, two test modes are proposed to simulate real user activity. By evaluating every single resource of web service automatically, a tester can not only find out internal problems but also understand the performance of the web service. In addition, the complete geographical test is available with the performance measurements coming from different regions in the world. Several experiments are performed to validate the functionality and usability of CTS. It demonstrates that CTS is a complete and reliable web service testing system, which provides unique functions and satisfies different requirements.
Elastic and cost-effective data carrier architecture for smart contract in blockchain
(2019-11-01)
Liu, Xiaolong
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Muhammad, Khan
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Lloret, Jaime
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Chen, Yu-Wen
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Yuan, Shyan-Ming
Smart contract, which could help developer deploy decentralized and secure blockchain application, is one of the most promising technologies for modern Internet of things (IoT) ecosystem today. However, Ethereum smart contract lacks of ability to communicate with outside IoT environment. To enable smart contracts to fetch off-chain data, this paper proposes a data carrier architecture that is cost-effective and elastic for blockchain-enabled IoT environment. Three components, namely Mission Manager, Task Publisher and Worker, are presented in the data carrier architecture to interact with contract developer, smart contract, Ethereum node and off-chain data sources. Selective solutions are also proposed for filtering smart contract event and decoding event log to fit different requirements. The evaluation results and discussions show the proposed system will decrease about 20USD deployment cost in average for every smart contract, and it is more efficient and elastic compared with Oraclize Oracle data carrier service. (C) 2019 Elsevier B.V. All rights reserved.
Exploring Students' Behaviors in Editing Learning Environment
(2018-01-01)
Zhang, Xuebai
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Liu, Xiaolong
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Yuan, Shyan-Ming
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Fan, Chia-Chen
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Sun, Chuen-Tsai
As a pathway for learning, remix has become one of the most important practices within the field of open educational resources. In this study, we investigate the searching and re-editing behavior of students in an online web environment. Participants were asked to search and remix the retrieved web information, which was based on the content of textbook. To explore learning process in the remixing environment, the relationships among function of thinking styles, the search behaviors, the edit behavior, pre-performance, and the final remixing performance are analyzed. Various behavior data are recorded, including web visiting log, interaction log and eye tracking data. The finding provides insight into how to understand the behaviors associated with underlying cognitive and learning performances.
Eye Movement Analysis of Digital Learning Content for Educational Innovation
(2020-03-02)
Liu, Xiaolong
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Zhang, Xuebai
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Chen, Wei-Wen
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Yuan, Shyan-Ming
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資訊工程學系
Eye movement technology is highly valued for evaluating and improving digital learning content. In this paper, an educational innovation study of eye movement behaviors on digital learning content is presented. We proposed three new eye movement metrics to explain eye movement behaviors. In the proposed method, the digital content, which were slide-deck-like works, were classified into page categories according to the characteristics of each page. We interpreted the subjects' eye movement behaviors on the digital slide decks. After data regularization and filtering, the results were analyzed to give directions for how to design an attractive digital learning content from the viewpoint of eye movement behaviors. The relationships between the subjects' evaluation scores, page categories, and eye movement metrics are discussed. The results demonstrated that the proposed fixation time percentage (FTP) was a representative, strong, and stable eye movement metric to measure the subjects' interest. Moreover, a reasonable portion of semantic content had a positive influence on the subjects' interest.
Eye Tracking Based Control System for Natural Human-Computer Interaction
(2017-01-01)
Zhang, Xuebai
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Liu, Xiaolong
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Yuan, Shyan-Ming
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Lin, Shu-Fan
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資訊工程學系
Eye movement can be regarded as a pivotal real-time input medium for human-computer communication, which is especially important for people with physical disability. In order to improve the reliability, mobility, and usability of eye tracking technique in user-computer dialogue, a novel eye control system with integrating both mouse and keyboard functions is proposed in this paper. The proposed system focuses on providing a simple and convenient interactive mode by only using user's eye. The usage flow of the proposed system is designed to perfectly follow human natural habits. Additionally, a magnifier module is proposed to allow the accurate operation. In the experiment, two interactive tasks with different difficulty (searching article and browsing multimedia web) were done to compare the proposed eye control tool with an existing system. The Technology Acceptance Model (TAM) measures are used to evaluate the perceived effectiveness of our system. It is demonstrated that the proposed system is very effective with regard to usability and interface design.
Joint Data Hiding and Compression Scheme Based on Modified BTC and Image Inpainting
(2019-01-01)
Liu, Xiaolong
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Lin, Chia-Chen
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Muhammad, Khan
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Al-Turjman, Fadi
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Yuan, Shyan-Ming
Seamlessly integrating image compression technique and secret data hiding technique into a single procedure for security and efficient data transmission is a novel research issue in modern, decentralized digital communication environments. The first joint data hiding and compression (JDHC) scheme on block truncation coding (BTC) compression domain is presented in this paper. In the compressing and embedding procedure, for the complex blocks, modified block truncation coding (MBTC) is utilized to embed secret data and compress blocks simultaneously, while further controlling the visual distortion that is caused during data embedding. For the smooth blocks, according to the current embedding bit, either image inpainting or block search order coding (BSOC) is used to embed secret data and compress blocks simultaneously with maintaining acceptable compression performance. According to the image compression codes that are provided as output, image decompression and secret bits extraction procedures can be conducted simultaneously. Experimental results indicate that outstanding compression bit rate can be achieved by the proposed JDHC scheme with satisfactory visual quality and hiding capacity.
Mobile Advertising System Based on User Provided Information in Exchange for Free Network Access
(2017-01-01)
Liu, Xiaolong
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Yuan, Shyan-Ming
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Zhang, Xuebai
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Wang, Pai-Hsuan
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資訊工程學系
With the rapid development of mobile communication technology, the significant increase in the number of mobile device users have created a very strong demand for effective mobile advertising. The key campaign success of advertising is putting right advertisements to right customers. This paper presents a place of interest based mobile advertising system that allows mobile advertising company obtained valuable information from cellphone users. After analyzing this information, mobile advertising company is able to publishing customized ads to the user's mobile device. In addition, cellphone users can get free mobile network data volume by reporting their places of interest. It has been demonstrated that the proposed system is easy to use and would benefit for not only mobile advertising company, but also cellphone user, and the others participations.
Off-chain Data Fetching Architecture for Ethereum Smart Contract
(2018-01-01)
Liu, Xiaolong
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Chen, Riqing
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Chen, Yu-Wen
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Yuan, Shyan-Ming
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資訊工程學系
Ethereum smart contract makes developers can deploy decentralized applications to inherit features from blockchain, such as decentralization and openness. Although Ethereum provided a decentralized platform, Ethereum Virtual Machine for smart contracts, it lacks of ability to fetch off-chain data. The general solution is Oracle data carrier. However, Oracle results in rising deployment costs. It requires Ethereum smart contract developers to follow format in programing contract, this constraint decreases the readability of smart contract. This paper proposes an off-chain data fetching architecture which is cost-effective and highly elastic for smart contract. It also compatible with exited contract, which makes Ethereum smart contract owner able to automate the reply process.
Resource reconfiguration module for cross-cloud system
(2017-01-01)
Liu, Xiaolong
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Yuan, Shyan-Ming
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Zhang, Xuebai
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Chung, Po-Yu
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資訊工程學系
Cloud computing has been an emerging technology paradigm that provides on-demand resource for systems over the Internet. Resource reconfiguration is an important issue in the life cycle of the system in cloud. This paper proposes a cross-cloud system reconfiguration module, which focused on being an assistance of reconfiguration task toward helping the system managers to reconfigure their cloud system easily. We propose a complete definition of reconfiguration command, and the proposed module covers the common requirements in the reconfiguration issue, such as scaling direction and scaling policy. With the help from Libcloud, the proposed module can achieve cross-cloud management. The module is also designed to avoid confliction with any possible existed technology and can be integrated with any other systems. Meanwhile, the comparisons with the related works are presented in this paper to demonstrate the superiority of the proposed module.