Browsing by Author "NCTU/ITRI Joint Research Center"

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3D Hand Posture Estimation and Task Semantic Monitoring Technique for Human-Robot Collaboration
(2013-01-01)
Hu, Jhen-Jia
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Li, Hui-Chieh
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Wang, Hau-Wei
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Hu, Jwu-Sheng
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電控工程研究所
We develop a monitoring system for human-robot collaboration (HRC) of hybrid automation. The system enables the production line to avoid product defects as well as guarantee a real-time warning system in a cellular manufacturing (CM). A task semantic monitoring system includes the three-dimensional (3D) hand posture estimation and the motion trajectory monitoring. The coordinate of hand, the motion of hand, and the semantic of hand are identified by two integrated modules. The verification is executed by applying the system to the assembly lines for power protector.
A Co-axial multi-tube heat exchanger applicable for a Geothermal ORC power plant
(2014-01-01)
Hsieh, J. C.
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Lee, Y. R.
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Guo, T. R.
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Liu, L. W.
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Cheng, P. Y.
The study proposes a Co-axial multi-tube heat exchanger (CMTHE) applicable to geothermal heat extraction. The heat exchanger is integrated with a 50 kW geothermal ORC power plant having a working fluid of R-245fa. Two field tests were performed to examine the system response of the ORC system subject to change of CMTHE. In case 1 where the flow rate in the shell-side of CMTHE is maintained, the pressure variation in the shell-side of CMTHE casts minor variations on heat extraction, ORC power generation, and ORC efficiency during the transient. Moreover, the effect of pressure has barely any influence of the final states of heat extraction, ORC power generation, and ORC efficiency. In case 2 where the pressure is preserved in the CMTHE, it is found that a decrease of flow rate in the CMTHE results in degradation of heat extraction, ORC power generation and ORC system efficiency. On the contrary, increasing the flow rate in the CMTHE leads to a rise of heat extraction, ORC power generation and ORC system efficiency. Unlike that in case 1, the effect of flow rate has a detectable effect on the final states of heat extraction, ORC power generation, and ORC efficiency. (C) 2014 Published by Elsevier Ltd.
A Feasiblity Study on Developing IoT/M2M Applications over ETSI M2M Architecture
(2013-01-01)
Lin, Fuchun Joseph
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Ren, Yi
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Cerritos, Eduardo
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交大工研院聯合研發中心
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NCTU/ITRI Joint Research Center
A common service platform is considered as the key enabler to catalyze the development of IoT/M2M applications for a large variety of vertical markets such as smart energy, smart transportation, home and industry automation, eHealth and connected vehicles. This paper reports an initial effort at National Chiao Tung University in Taiwan with such an experimental approach. We first train our graduate students with an ETSI M2M architecture-compliant service platform OpenMTC from FOKUS, and then charter them with the tasks of developing diverse M2M applications. The effort is used as a feasibility study to investigate how useful the notion of a common service platform for IoT/M2M is and how urgent an international standard is required in defining such a platform. We intend to use the result of the study to create a suitable IoT/M2M curriculum for our students.
A Q-learning-based multi-rate transmission control scheme for RRC in WCDMA systems
(2002-01-01)
Ren, FC
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Chang, CJ
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Chen, YS
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交大工研院聯合研發中心
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NCTU/ITRI Joint Research Center
In this paper, a Q-learning-based multi-rate transmission control scheme (Q-MRTC) for radio resource control (RRC) in WCDMA systems is proposed. The RRC problem is modelled as a semi-Markov decision process (SMDP). And we successfully apply a real-time reinforcement learning algorithm, named Q-learning, to accurately estimate the transmission cost for the multi-rate transmission control. For the cost function approximation, we apply the feature extraction method to map the original state space into a more compact set which represents the resultant interference profile. Simulation results show that the Q MRTC can achieve higher system throughput and better users' satisfaction index, by an amount of 87% and 50%, respectively, than the interference-based multi-rate transmission control scheme, while keeping the QoS requirement.
A Similarity-Based Learning Algorithm Using Distance Transformation
(2015-06-01)
Hu, Yuh-Jyh
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Yu, Min-Che
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Wang, Hsiang-An
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Ting, Zih-Yun
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交大工研院聯合研發中心
Numerous theories and algorithms have been developed to solve vectorial data learning problems by searching for the hypothesis that best fits the observed training sample. However, many real-world applications involve samples that are not described as feature vectors, but as (dis) similarity data. Converting vectorial data into (dis) similarity data is more easily performed than converting (dis) similarity data into vectorial data. This study proposes a stochastic iterative distance transformation model for similarity-based learning. The proposed model can be used to identify a clear class boundary in data by modifying the (dis) similarities between examples. The experimental results indicate that the performance of the proposed method is comparable with those of various vector-based and proximity-based learning algorithms.
Content-aware fast motion estimation algorithm
(2008-05-01)
Chen, Yi-Wen
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Hsiao, Ming-Ho
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Chen, Hua-Tsung
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Liu, Chi-Yu
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Lee, Suh-Yin
In this paper, we propose the Content-Aware Fast Motion Estimation Algorithm (CAFME) that can reduce computation complexity of motion estimation (ME) in H.264/AVC while maintaining almost the same coding efficiency. Motion estimation can be divided into two phases: searching phase and matching phase. In searching phase.. we propose the Simple Dynamic Search Range Algorithm (SDSR) based on video characteristics to reduce the number of search points (SP). In matching phase, we integrate the Successive Elimination Algorithm (SEA) and the integral frame to develop a new SEA for H.264/AVC video compression standard, called Successive Elimination Algorithm with Integral Frame (SEAIF). Besides, we also propose the Early Termination Algorithm (ETA) to early terminate the motion estimation of current block. We implement the proposed algorithm in the reference software JM9.4 of H.264/AVC and the experimental results show that our proposed algorithm can reduce the number of search points about 93.1%, encoding time about 42%, while maintaining almost the same bitrate and PSNR. (c) 2008 Elsevier Inc. All rights reserved.
Content-aware video adaptation under low-bitrate constraint
(2007)
Hsiao, Ming-Ho
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Chen, Yi-Wen
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Chen, Hua-Tsung
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Chou, Kuan-Hung
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Lee, Suh-Yin
With the development of wireless network and the improvement of mobile device capability, video streaming is more and more widespread in such an environment. Under the condition of limited resource and inherent constraints, appropriate video adaptations have become one of the most important and challenging issues in wireless multimedia applications. In this paper, we propose a novel content- aware video adaptation in order to e. effectively utilize resource and improve visual perceptual quality. First, the attention model is derived from analyzing the characteristics of brightness, location, motion vector, and energy features in compressed domain to reduce computation complexity. Then, through the integration of attention model, capability of client device and correlational statistic model, attractive regions of video scenes are derived. The information object- ( IOB-) weighted rate distortion model is used for adjusting the bit allocation. Finally, the video adaptation scheme dynamically adjusts video bitstream in frame level and object level. Experimental results validate that the proposed scheme achieves better visual quality effectively and effciently.
Converging MQTT resources in ETSI standards based M2M platform
(2014)
Chen, Hsiang Wen
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Lin, Fuchun Joseph
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資訊工程學系
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交大工研院聯合研發中心
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Department of Computer Science
One of the key challenges of the Internet of Things (IoT) is the integration of heterogeneous technologies and communications solutions. This paper proposes a method to integrate Message Queuing Telemetry Transport (MQTT) protocol with the ETSI M2M architecture via a new network function called MQTT proxy. The MQTT proxy, on the one side, acts as an MQTT broker to the MQTT clients. While on the other side, it serves as a Gateway Application (GA) for interfacing with the ETSI M2M-compliant architecture, specifically OpenMTC developed by Fraunhofer FOKUS. By the MQTT Proxy, MQTT resources can be converged in the ETSI M2M architecture. Finally, we compare the MQTT Proxy with our previous HTTP Proxy.
General formulation of shift and delta operator based 2-D VLSI filter structures without global broadcast and incorporation of the symmetry
(2014-10-01)
Khoo, I. -Hung
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Reddy, Hari C.
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Van, Lan-Da
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Lin, Chin-Teng
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資訊工程學系
Having local data communication (without global broadcast of signals) among the elements is important in very large scale integration (VLSI) designs. Recently, 2-D systolic digital filter architectures were presented which eliminated the global broadcast of the input and output signals. In this paper a generalized formulation is presented that allows the derivation of various new 2-D VLSI filter structures, without global broadcast, using different 1-D filter sub-blocks and different interconnecting frameworks. The 1-D sub-blocks in z-domain are represented by general digital two-pair networks which consist of direct-form or lattice-type FIR filters in one of the frequency variables. Then, by applying the sub-blocks in various frameworks, 2-D structures realizing different transfer functions are easily obtained. As delta discrete-time operator based 1-D and 2-D digital filters (in gamma-domain) were shown to offer better numerical accuracy and lower coefficient sensitivity in narrow-band filter designs when compared to the traditional shift-operator formulation we have covered both the conventional z-domain filters as well as delta discrete-time operator based filters. Structures realizing general 2-D IIR (both z- and gamma-domains) and FIR transfer functions (z-domain only) are presented. As symmetry in the frequency response reduces the complexity of the design, IIR transfer functions with separable denominators, and transfer functions with quadrantal magnitude symmetry are also presented. The separable denominator frameworks are needed for quadrantal symmetry structures to guarantee BIBO stability and thus presented for both the operators. Some limitations of having exact symmetry with separable 1-D denominator factors are also discussed.
Interdomain Identity-Based Key Agreement Schemes
(2014-01-01)
Fan, Chun-I
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Lin, Yi-Hui
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Hsu, Tuan-Hung
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Hsu, Ruei-Hau
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交大工研院聯合研發中心
In order to simplify key management, two-party and three-party key agreement schemes based on user identities have been proposed recently. Multiparty (including more than three parties) key agreement protocols, which also are called conference key schemes, can be applied to distributed systems and wireless environments, such as ad hoc networks, for the purpose of multiparty secure communication. However, it is hard to extend two- or three-party schemes to multiparty ones with the guarantee of efficiency and security. In addition to the above two properties, interdomain environments should also be considered in key agreement systems due to diversified network domains. However, only few identity-based multiparty conference key agreement schemes for single domain environments and none for interdomain environments were proposed in the literature and they did not satisfy all of the security attributes such as forward secrecy and withstanding impersonation. In this paper, we will propose a novel efficient single domain identity-based multiparty conference key scheme and extend it to an interdomain one. Finally, we prove that the proposed schemes satisfy the required security attributes via formal methods.
IPsec-Based VoIP Performance in WLAN Environments
(2008-11-01)
Sung, Ya-Chin
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Lin, Yi-Bing
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資訊工程學系
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交大工研院聯合研發中心
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Department of Computer Science
The Third-Generation Partnership Project (3GPP) specifies 3G-WLAN interworking that lets mobile stations (MSs) access 3G networks via WLAN-based packet data gateways (PDGs). The specification mandates that packets delivered between an MS and a PDG should be protected by IPsec. This article studies IPsec-based VoIP performance (in terms of throughput, packet loss rate, latency, and jitter) in the 3G-WLAN integration environment. The study is designed to provide guidelines for selecting appropriate system parameter values for VoIP over WLAN.
Kinematic Calibration of Manipulator Using Single Laser Pointer
(2012-01-01)
Hu, Jwu-Sheng
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Wang, Jyun-Ji
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Chang, Yung-Jung
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電子工程學系及電子研究所
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交大工研院聯合研發中心
This paper proposes a robot kinematic calibration system including a laser pointer installed on the manipulator, a stationary camera, and a planar surface. The laser pointer beams to the surface, and the camera observes the projected laser spot. The position of the laser spot is computed according to the geometrical relationships of line-plane intersection. The laser spot position is sensitive to slight difference of the end-effector pose due to the extensibility of laser beam. Inaccurate kinematic parameters cause inaccurate calculation of the end-effector pose, and then the laser spot position by the forward estimation is deviated from the one by camera observation. For calibrating the robot kinematics, the optimal solution of kinematic parameters is obtained by minimizing the laser spot position difference between the forward estimation and camera measurement via the nonlinear optimization method. The proposed kinematic calibration system is cost-efficient and flexible for any manipulator. The proposed method is validated by simulation and experiment.
Low Complexity MIMO Detection by using Overlapped Cluster Search
(2015)
Chu, Jian-Ya
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Liao, Yuan-Te
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Hsu, Terng-Yin
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交大工研院聯合研發中心
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NCTU/ITRI Joint Research Center
In this paper, a low complexity overlapped cluster search algorithm which is employed in MIMO detection is proposed. The proposed algorithm allows more than one clusters possess the same candidate constellation points to decrease the possibility of choosing the wrong cluster while picking candidates. The proposed algorithm can maintain performance within 0.57dB such that the method is suitable for practical 4T4R 64QAM MIMO system. The algorithm complexity is reduce 27.29% to 56.25% in average case and 39.06% to 57.25% in worst case. Through simulation in IEEE 802.11n platform with TGN channel E, it indicates the complexity of proposed algorithm is less than the K-best SD with the same performance. Hence, the proposed algorithm provides a near-optimal solution with low computation complexity design for wireless MIMO system.
PERFORMANCE MEASUREMENTS OF TD-LTE, WIMAX AND 3G SYSTEMS
(2013-06-01)
Lin, Yi-Bing
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Lin, Pin-Jen
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Sung, Yingrong Coral
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Chen, Yuan-Kai
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Chen, Whai-En
Long Term Evolution (LTE) and Worldwide Interoperability for Microwave Access (WiMAX) are two major technologies toward next-generation mobile broadband standards, which are both expected to provide higher throughput and lower transmission latency for mobile users. This article measures and compares the latency and the throughput of Time Division - Long Term Evolution (TD-LTE), WiMAX, and third-generation (3G) systems based on several technical trials. Our quantitative measures and comparisons provide guidelines for the operators to deploy their future networks.
Physics-based ball tracking and 3D trajectory reconstruction with applications to shooting location estimation in basketball video
(2009-04-01)
Chen, Hua-Tsung
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Tien, Ming-Chun
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Chen, Yi-Wen
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Tsai, Wen-Jiin
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Lee, Suh-Yin
The demand for computer-assisted game study in sports is growing dramatically. This paper presents a practical video analysis system to facilitate semantic content understanding. A physics-based algorithm is designed for ball tracking and 3D trajectory reconstruction in basketball videos and shooting location statistics can be obtained. The 2D-to-3D inference is intrinsically a challenging problem due to the loss of 3D information in projection to 2D frames. One significant contribution of the proposed system lies in the integrated scheme incorporating domain knowledge and physical characteristics of ball motion into object tracking to overcome the problem of 2D-to-3D inference. With the 2D trajectory extracted and the camera parameters calibrated, physical characteristics of ball motion are involved to reconstruct the 3D trajectories and estimate the shooting locations. Our experiments on broadcast basketball videos show promising results. We believe the proposed system will greatly assist intelligence collection and statistics analysis in basketball games. (C) 2008 Elsevier Inc. All rights reserved.
Reducing Call Routing Cost for Femtocells
(2010-07-01)
Lin, Yi-Bing
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Gan, Chai-Hien
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Liang, Ching-Feng
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資訊工程學系
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交大工研院聯合研發中心
Femtocell is an effective solution to improve indoor coverage for cellular networks, where short-range and low-power Base Stations (BSs) called Femto BSs are deployed in small areas (e. g., buildings). We propose the Femto Private Branch Exchange (FPBX) to concentrate the traffic of the Femto BSs in a specific area, such as a campus or an enterprise with central or distributed locations. Through the FPBX, a normal cellular call between two Femto users can be replaced by a low-cost extension call. Therefore, the call routing cost can be significantly reduced. In this approach, the existing mobile network nodes are not modified. We analytically analyze the call routing performance for the FPBX approach, and develop simulation experiments to validate against the analytic model. Our study indicates that the FPBX approach can effectively reduces the call setup costs and the voice trunk costs among Femto users by slightly increasing the normal cellular call setup costs.
Semantic Similarity Measures in the Biomedical Domain by Leveraging a Web Search Engine
(2013-07-01)
Hsieh, Sheau-Ling
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Chang, Wen-Yung
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Chen, Chi-Huang
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Weng, Yung-Ching
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交大名義發表
Various researches in web related semantic similarity measures have been deployed. However, measuring semantic similarity between two terms remains a challenging task. The traditional ontology-based methodologies have a limitation that both concepts must be resided in the same ontology tree(s). Unfortunately, in practice, the assumption is not always applicable. On the other hand, if the corpus is sufficiently adequate, the corpus-based methodologies can overcome the limitation. Now, the web is a continuous and enormous growth corpus. Therefore, a method of estimating semantic similarity is proposed via exploiting the page counts of two biomedical concepts returned by Google AJAX web search engine. The features are extracted as the co-occurrence patterns of two given terms P and Q, by querying P, Q, as well as P AND Q, and the web search hit counts of the defined lexico-syntactic patterns. These similarity scores of different patterns are evaluated, by adapting support vector machines for classification, to leverage the robustness of semantic similarity measures. Experimental results validating against two datasets: dataset 1 provided by A. Hliaoutakis; dataset 2 provided by T. Pedersen, are presented and discussed. In dataset 1, the proposed approach achieves the best correlation coefficient (0.802) under SNOMED-CT. In dataset 2, the proposed method obtains the best correlation coefficient (SNOMED-CT: 0.705; MeSH: 0.723) with physician scores comparing with measures of other methods. However, the correlation coefficients (SNOMED-CT: 0.496; MeSH: 0.539) with coder scores received opposite outcomes. In conclusion, the semantic similarity findings of the proposed method are close to those of physicians' ratings. Furthermore, the study provides a cornerstone investigation for extracting fully relevant information from digitizing, free-text medical records in the National Taiwan University Hospital database.
Structural Building Blocks Construction of Protein 3-D Structures Using a Structural Variant of Mountain Clustering Method
(2009-07-01)
Lin, Ken-Li
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Lin, Chin-Teng
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Pal, Nikhil R.
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Ojha, Sudeepta
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電控工程研究所
Toward the Human-Robot Co-Existence Society: On Safety Intelligence for Next Generation Robots
(2009-11-01)
Weng, Yueh-Hsuan
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Chen, Chien-Hsun
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Sun, Chuen-Tsai
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交大工研院聯合研發中心
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NCTU/ITRI Joint Research Center
Technocrats from many developed countries, especially Japan and South Korea, are preparing for the human-robot co-existence society that they believe will emerge by 2030. Regulators are assuming that within the next two decades, robots will be capable of adapting to complex, unstructured environments and interacting with humans to assist with the performance of daily life tasks. Unlike heavily regulated industrial robots that toil in isolated settings, Next Generation Robots will have relative autonomy, which raises a number of safety issues that are the focus of this article. Our purpose is to describe a framework for a legal system focused on Next Generation Robots safety issues, including a Safety Intelligence concept that addresses robot Open-Texture Risk. We express doubt that a model based on Isaac Asimov's Three Laws of Robotics can ever be a suitable foundation for creating an artificial moral agency ensuring robot safety. Finally, we make predictions about the most significant Next Generation Robots safety issues that will arise as the human-robot co-existence society emerges.
Tracking dynamic near-regular texture under occlusion and rapid movements
(2006)
Lin, WC
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Liu, YX
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交大工研院聯合研發中心
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NCTU/ITRI Joint Research Center
We present a dynamic near-regular texture (NRT) tracking algorithm nested in a lattice-based Markov-Random-Field (MRF) model of a 3D spatiotemporal space. One basic observation used in our work is that the lattice structure of a dynamic NRT remains invariant despite its drastic geometry or appearance variations. On the other hand, dynamic NRT imposes special computational challenges to the state of the art tracking algorithms: including highly ambiguous correspondences, occlusions, and drastic illumination and appearance variations. Our tracking algorithm takes advantage of the topological invariant property of the dynamic NRT by combining a global lattice structure that characterizes the topological constraint among multiple textons and an image observation model that handles local geometry and appearance variations. Without any assumptions on the types of motion, camera model or lighting conditions, our tracking algorithm can effectively capture the varying underlying lattice structure of a dynamic NRT in different real world examples, including moving cloth, underwater patterns and marching crowd.