Browsing by Author "Lin, Chia-Yu"

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A Flexible Analysis and Prediction Framework on Resource Usage in Public Clouds
(2012)
Lin, Chia-Yu
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Chen, Yan-Ann
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Tseng, Yu-Chee
;
Wang, Li-Chun
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資訊工程學系
In cloud computing environments, users can rent virtual machines (VMs) from cloud providers to execute their programs or provide network services. While using this kind of cloud services, one of the biggest problems for the users is to determine the proper number of VMs to complete the jobs considering both budget and time. In this paper, we propose a resource prediction framework (RPF), which can help users choose the minimum number of virtual machines to complete their jobs within a user specified time constraint. In order to verify the feasibility of RPF, we have done three case studies, namely parallel frequent pattern growth (FP-Growth), parallel K-means, and Particle Swarm Optimization (PSO). FP-growth, K-means and PSO are data intensive algorithms. These algorithms are typically executed repeatedly with different execution parameters to find the optimal results. When evaluating RPF by these algorithms in cloud environments, we have to modify them to parallel versions. The evaluation results indicate that RPF can successfully obtain the minimum number of VMs with acceptable errors. According to our case studies, the proposed RPF can be adopted by data intensive jobs by providing flexibility to both end users and cloud system providers.
A Personal Emergency Communication Service for Smartphones using FM transmitters
(2013-01-01)
Chen, Yu-Jia
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Lin, Chia-Yu
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Wang, Li-Chun
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交大名義發表
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National Chiao Tung University
Communication networks such as cellular phone networks are quite likely to be severely damaged during a large-scale of disaster, making SOS message dissemination to rescue authorities extremely difficult. In this paper, we first propose a FM radio-based emergency communication service through the integration of FM transmitters into smartphones. FM radio provides a number of advantages such as longer propagation length and less susceptible to obstacles, making it suitable for broadcasting SOS messages. Besides, we design Morse code-based SOS message dissemination using FM transmitters (MCSOS-FM) and its corresponding communication procedure for the emergency communication service in order to improve communication range, victim localization and evacuation route planning. The combination of FM radio and Morse code is completely compatible with the current radio system equipped by rescue workers, and thus increases the possibilities of successful receiving and recognizing SOS messages. Our experiment result based on smartphone implementation shows that the proposed emergency communication service is cost effective and energy efficient with relatively large communication range.
A Privacy-Preserved Joint Group Time Scheduling Mechanism for Mobile Social Applications
(2013)
Chen, Yu-Jia
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Lin, Chia-Yu
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Wang, Li-Chun
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交大名義發表
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National Chiao Tung University
In this paper, we develop a privacy preserving mechanism for a scheduling service for a group of users, which can compute the joint available time based on users' calendar information. We also propose a weighted voting game with partially homomorphic encryption (WVGPHE) scheme to protect the privacy of users' calendar information as well as users' weight. Even with the privacy protection, our experimental results show that the proposed scheme is still very computational and bandwidth efficient enough to provide immediate group meeting in mobile communications environments.
A Proximity Sensor Based No-Touch Mechanism for Mobile Applications on Smart Phones
(2012-01-01)
Lin, Chia-Yu
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Chen, Yu-Jia
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Wang, Li-Chun
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Tseng, Yu-Chee
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電機工程學系
Smart phones with touch screens have become very popular and have changed our behaviors of using handsets. However, using touch screens is not safe for mobile phone users especially when they are driving cars. Thus, many applications using smart phones cannot be initiated because users who are driving the cars cannot easily touch the small icons on the screens of smart phones. To overcome this issue, we propose a proximity sensors based "no-touch" mechanism for smart phones by applying proximity sensors to initiate mobile applications without the need of touching the screen. We will discuss how to implement the proximity-sensors driven "no-touch" mechanism in Android platform and investigate its performance issues regarding detection accuracy and power consumption. Speech-oriented applications using the proposed "no-touch" mechanism on Android is also demonstrated in this paper.
An Effective Algorithm for Interest Aware Opportunistic Advertising by Mining Social and Consuming Information
(2014-01-01)
Lin, Chia-Yu
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Jiang, Zhi-Feng
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Wang, Li-Chun
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Lin, Bao-Shuh Paul
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資訊工程學系
Advertisements and coupon forwarding among mobile devices and social platforms become significant in recent years. However, when users are in the crowded places where the network connection is unstable such as shopping malls, forwarding of advertisements to target users in limited time is challenge. Thus, we propose an interest-aware opportunistic advertising by mining social and consuming information system (ISC) and algorithm. In ISC system, we combine social relationship and consuming information to find out the consumers who have similar interest. ISC algorithm adopts the result of ISC system to reduce the delay of broadcasting advertisement and increase the advertisement effect. We also implement and evaluate the performance of ISC system and algorithm on mobile devices and the ONE simulator. Our experiment results show that ISC algorithm is cost effective and intensively magnify the advertising effeteness with many customers under uncertain network and time-limited environments.
Electrical properties of single and multiple poly(3,4-ethylenedioxythiophene) nanowires for sensing nitric oxide gas
(2009-04-27)
Lu, Hui-Hsin
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Lin, Chia-Yu
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Hsiao, Tzu-Chien
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Fang, Yueh-Yuan
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Ho, Kuo-Chuan
The electrical properties of conducting polymer, poly(3,4-ethylenedioxythiophene) (PEDOT), nanowires were studied to develop nitric oxide (NO) gas sensors with low working temperatures. A nanowire with a diameter of 300 nm was fabricated using dip-pen nanolithography (DPN) across a 55 mu m gap between a pair of electrodes. The electrical properties of single or multiple PEDOT nanowires were examined by plotting the current-voltage (I-V) curves in the range -3 V to +3 V at temperatures between 298 K and 393 K. The conductance of parallel wires was normalized with respect to the dimensions of the fabricated nanowires. The single nanowire exhibited nonlinear conductance associated with hysteresis but multiple wires did not. The currents increased with the temperature and the I-V characteristics were consistent with the power lawG(T)alpha T(alpha) with alpha similar to 5.14 and 5.43. The responses to NO were highly linear and reproducible, indicating that sensing using PEDOT nanowires was reliable with a minimal concentration of NO of 10 ppm. (c) 2009 Elsevier B.V. All rights reserved.
Hybrid Real-Time Matrix Factorization for Implicit Feedback Recommendation System
(2018-01-01)
Lin, Chia-Yu
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Wang, Li-Chun
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Tsai, Kun-Hung
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電機工程學系
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Department of Electrical and Computer Engineering
In this paper, we present a hybrid real-time incremental stochastic gradient descent (RI-SGD) updating technique for implicit feedback matrix factorization (MF) recommendation systems. Compared with explicit feedback evaluation scores, implicit feedback data are easier to obtain but pose challenges to MF recommendation systems because of the transformation procedures from raw data to user preference scores. Another challenge for MF recommendation systems is the accuracy issue when the speed of the new input data increases. The proposed RI-SGD is designed for computationally-efficient and accurate time-variant implicit feedback MF recommendation system, which consists of alternating least squares with weight regularization in the training phase and stochastic gradient descent in the updating phase. To demonstrate the advantages of the RI-SGD updating technique in terms of computational efficiency and accuracy, we implement the proposed updating techniques in a real-time music recommendation system. Compared with the method of retraining the entire model, our numerical results show that RI-SGD approach can achieve almost the same recommendation accuracy, but requires only about 0.02% of the retraining time.
Nanophotonic structures for highly efficient on-chip optical manipulation
(2018-01-01)
Lee, Po-Tsung
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Lu, Tsan-Wen
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Lin, Pin-Tso
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Lin, Chia-Yu
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Tsai, Chia-Yang
In this report, we introduce our proposed nanophotonic structures for highly efficient optical manipulation, including utilizing photonic crystal waveguides, nanocavities, and metallic structures with localized surface plasmon resonances. Owing to their waveguide-accessible configurations and highly concentrated optical modes with large field gradients beyond the diffraction limit, highly efficient optical trapping can be realized in sub-wavelength scale.
New Strategy for Minimally Invasive Endoscopic Surgery to Treat Infectious Spondylodiscitis in the Thoracolumbar Spine
(2019-05-01)
Lin, Chia-Yu
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Chang, Chien-Chun
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Chen, Yen-Jen
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Tsai, Chun-Hao
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Tsou, Hsi-Kai
Background: Eradicating infection, protecting neurologic function, and maintaining structural alignment are the 3 objectives of treatment for infectious spondylodiscitis. For some patients, surgery may be necessary to achieve these goals; however, open surgeries are associated with high morbidity and mortality in elderly patients and those with multiple comorbidities. Endoscopic surgery provides a minimally invasive surgical option for obtaining a culture sample to aid identification of pathogens, while also providing a route for adequate decompression and drainage. The clinical results of this study were analyzed. Objectives: To evaluate the efficacy and safety of spinal endoscopic surgery, the basic characteristics of patients analyzed and their inflammatory markers, pain levels, and local kyphotic angles were recorded before surgery and at regular intervals after surgery. The patients' cultured pathogens and previous antibiotic treatments were also recorded and analyzed. Study Design: Retrospective observational study (institutional review board: CMUH 105-REC2-101). Setting: Inpatient surgery center. Methods: From October 2006 to March 2017, of 508 patients who received spinal endoscopic surgery, 60 with infectious spondylodiscitis were treated using this new strategy. All 60 patients underwent plain film radiography and enhanced magnetic resonance imaging of the affected region to obtain evidence of infectious spondylodiscitis. The role of a computed tomography-guided biopsy and some indications for open surgery were replaced with endoscopic surgery. Results: All the patients reported rapid pain relief after endoscopic surgery and antibiotic treatment. No significant changes in sagittal alignment were observed in final follow-up radiography images. Causative pathogens were identified in 34 patients (culture rate: 77.27%) without previous antibiotic treatment. The patients' erythrocyte sedimentation rates and C-reactive protein levels had decreased significantly 3 months after endoscopic surgery. Two patients (3.3%) experienced infection relapse following initial endoscopic surgery; both of them were efficiently resolved through a second round of endoscopic surgery. No surgery-related complications were observed and no open spinal surgery was required during the follow-up period. Limitations: This was a retrospective study; bias was unavoidable because of the single-center nature of the study design. Conclusions: Regarding the culture rate, recurrence rate, kyphotic change, and surgery-related complications, this new strategy for endoscopic surgery is safe and effective for treating infectious spondylodiscitis in the thoracic or lumbar spine and may be considered a new trend in treating diseases of this type.
NO Gas Sensor of PEDOT: PSS Nanowires by Using Direct Patterning DPN
(2008)
Lu, Hui-Hisn
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Lin, Chia-Yu
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Fang, Yueh-Yuan
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Hsiao, Tzu-Chien
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Ho, Kuo-Chuan
Nitric oxide (NO) detection is a critical issue for environmental safety and medical diagnosis due reasons with regard to the toxic properties for human body and metabolic index for respiratory disease, respectively. Development of gas sensor with high sensitivity is very important because the concentration of NO gas in the environment and respiratory tract is extremely low, therefore not readily detectable. The material with nanostructure can improve the sensitivity of sensor owning to surface effect and size effect. Herein, we developed a new type of gaseous nanosensor assembled by 34 nanowires of conducting polymer, PEDOT: PSS. The nanowires were fabricated by dip pen nanolithography (DPN) with the length of 55 um and diameter of 300 nm between golden wires. The NO gas measurement is based on chemiresistor based methods. The result of dynamic measurement of NO gas at 100 ppm shows repeatability and stability; the recovery time is 10.4 minutes. Moreover, the lowest concentration of NO gas in static measurement is 10ppm at 80 C, which also shows the ability sensing at low temperature.
Reconstruct Dynamic Systems from Large-Scale Open Data
(2015)
Tsai, Kun-Hung
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Lin, Chia-Yu
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Wang, Li-Chun
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Chen, Jian-Ren
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電機學院
With the prosperity of e-commerce, on-line vendors use recommendation systems in different fields. Classic recommendation algorithms are designed assuming that data is stationary and will not change over time. However, since the scale and variability of data are growing gradually, these methods will encounter the issues of the memory deficient and the out-of-date model, which degrade the recommendation accuracy intensively. In addition, retraining the whole model for every new arrival record results in high complexity. In this paper we propose a light-weight adaptive updating method to overcome these issues. Comparing with the explicit feedback recommendation, which asks the customers to express their opinions on the recommended items, the implicit feedback recommendation is easier to collect and non-intrusive way. However, the dynamic time-variant system with implicit feedback has not been seen in the literature. In this paper, we propose a real-time incremental updating algorithm (RI-SGD) to deal with time-variant systems based on the implicit feedback. We compare our method with methods that retraining the whole model and show that our method costs less than 1% of the retraining time with a competitive accuracy.
Sandwich-Nanostructured n-Cu2O/AuAg/p-Cu2O Photocathode with Highly Positive Onset Potential for Improved Water Reduction
(2019-10-23)
Lin, Yu-Chang
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Hsu, Liang-Ching
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Lin, Chia-Yu
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Chiang, Chao-Lung
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Chou, Che-Min
An n-Cu2O layer formed a high-quality buried junction with p-Cu2O to increase the photovoltage and thus to shift the turn-on voltage positively. Mott-Schottky measurements confirmed that the improvement benefited from a positive shift in flat-band potential. The obtained extremely positive onset potential, 0.8 V-RHE in n-Cu2O/AuAg/p-Cu2O, is comparable with measurements from water reduction catalysts. The AuAg alloy sandwiched between the homo-junction of n-Cu2O and p-Cu2O improved the photocatalytic performance. This alloy both served as an electron relay and promoted electron-hole pair generation in nearby semiconductors; the charge transfer between n-Cu2O and p-Cu2O in the sandwich structure was measured with X-ray absorption spectra. The proposed sandwich structure can be considered as a new direction for the design of efficient solar-related devices.
Seizure After Percutaneous Endoscopic Surgery?Incidence, Risk Factors, Prevention, and Management
(2020-06-01)
Lin, Chia-Yu
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Chang, Chien-Chun
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Tseng, Chun
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Chen, Yen-Jen
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Tsai, Chun-Hao
Sensors-Assisted Rescue Service Architecture in Mobile Cloud Computing
(2013)
Chen, Yu-Jia
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Lin, Chia-Yu
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Wang, Li-Chun
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交大名義發表
;
National Chiao Tung University
In this paper, we propose a sensors-assisted rescue service architecture to integrate rescue schemes for different purposes, including disaster prediction, evacuation planning, and emergency broadcast. In the proposed architecture, multiple-sensed mobile devices are designed to provide a personalized situational awareness, thereby further enhancing the flexibility and efficiency of rescue services. Reliability and scalability of rescue services are improved by leveraging the dynamical resource provision of cloud computing. The proposed rescue service architecture is implemented to show the advantages of power efficiency and scalability of the proposed rescue service architecture.
Signal and Information Processing in Mobile Cloud Computing: Trends and Challenges
(2015)
Lin, Chia-Yu
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Wang, Li-Chun
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電機學院
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College of Electrical and Computer Engineering
Mobile devices become popular with the help of hardware improvements and new functions supported by many sensors. In this paper, we propose a mobile and multi-sensing fusion platform to integrate the unstructured streaming sensing data collecting as well as processing technology and build a QoS performance model to estimate the computing resource of the platform. We also demonstrate three mobile and multi-sensing fusion applications as the examples on the platform. Besides, we discuss the trend and challenges of combining the mobile and multi-sensing fusion technology and signal and information processing in mobile cloud computing in great detail.