Department of Mechatronics and Robotics

ADDRESS
Department of Mechatronics and Robotics
Xi'an Jiaotong-Liverpool University
111 Ren'ai Road Suzhou Dushu Lake Science and Education Innovation District , Suzhou Industrial Park
Suzhou,Jiangsu Province,P. R. China,215123
1. Special issue on computational intelligence for social media data mining and knowledge discovery

Author:Li, Y;Shyamasundar, RK;Wang, XH

Source:COMPUTATIONAL INTELLIGENCE,2021,Vol.37

2. Computation of macro-fiber composite integrated thin-walled smart structures

Author:Zhang, SQ;Zhang, SY;Chen, M;Bai, J;Li, J

Source:2016 GLOBAL CONFERENCE ON POLYMER AND COMPOSITE MATERIALS (PCM 2016),2016,Vol.137

Abstract:Due to high flexibility, reliability, and strong actuation forces, piezo fiber based composite smart material, macro-fiber composite (MFC), is increasingly applied in various fields for vibration suppression, shape control, and health monitoring. The complexity arrangement of MFC materials makes them difficult in numerical simulations. This paper develops a linear electro-mechanically coupled finite element (FE) model for composite laminated thin-walled smart structures bonded with MFC patches considering arbitrary piezo fiber orientation. Two types of MFCs are considered, namely, MFC-d31 in which the d(31) effect dominates the actuation forces, and MFC-d33 which mainly uses the d(33) effect. The proposed FE model is validated by static analysis of an MFC bonded smart plate.
3. Automatic Building and Floor Classification using Two Consecutive Multi-layer Perceptron

Author:Cha, J;Lee, S;Kim, KS

Source:2018 18TH INTERNATIONAL CONFERENCE ON CONTROL, AUTOMATION AND SYSTEMS (ICCAS),2018,Vol.2018-October

Abstract:Key issues of indoor localization is taking full advantages and overcoming its disadvantages. indoor localization based on Wi-Fi fingerprinting attracts researchers' attentions since it does not require new infrastructure and devices. Many devices such as smart phones and laptops, which have a function to capture Wi-Fi signals, can be used for Wi-Fi fingerprinting. However, due to unreliable Wi-Fi signals, there are still difficulty to achieve high positioning accuracy. The unreliable signal disturbs devices to find their locations. As a result, getting localization with devices sometimes makes a wrong decision in building classification. It is useless for people to find a destination floor if they are in different building. In this paper, we propose two consecutive multi-layer perceptrons to get more precise localization. With sumple structure, we get better performance and show precise decision results in building classification, which is critical in Wi-Fi fingerprinting. We use UJIndoorLoc dataset which is open dataset.
4. Segregated Lightweight Dynamic Rate (SLDR) control scheme for efficient internet communications

Author:Ting,T. O.;Ting,H. C.;Lee,Sanghyuk

Source:Lecture Notes in Electrical Engineering,2013,Vol.235 LNEE

Abstract:This paper proposes an effective Segregated Lightweight Dynamic Rate Control Scheme (SLDRCS) over the internet. Based on the feedback analysis of the current approaches, we found that the indicator of the congestion is only the queue length. It only captures a partial indicator of delay and loss in feedback mechanism. This may result in an ineffective way in controlling the network when congestion control occurs. Therefore, we suggest multiple congestion indicators to adapt inside this scheme to fully control the average delay and loss from bidirectional of sender to receiver. The behavior of next event packet being control using discrete event simulation tool with First Come First Serve (FCFS) scheduling policy and we code this algorithm into C programming language. Through the simulation results, our Segregated Lightweight Dynamic Rate Control Scheme (SLDRCS) guaranteed high improvement in packet drop and average delay under various congestion level and traffic load conditions compare with the current approach. © 2013 Springer Science+Business Media Dordrecht.
5. Shakedown loading capacity prediction of metal-based nanocomposites

Author:Soleimanian,Sina;Chen,Min;Tate,Derrick;Zhang,Shunqi

Source:Journal of Physics: Conference Series,2019,Vol.1303

Abstract:© 2019 IOP Publishing Ltd. Nano reinforcement of metals cannot escape the attention of designers who seek to improve overall performance of engineering structures from automotive components to biomedical devices. Since many engineering structures are susceptible to variable cyclic load, presenting shakedown design of them is of the present research interest. So that, in the present research the shakedown loading capacity of metal based nanocomposite is estimated through finite element discretization and interior point optimization method. Finally, the results are obtained for plate structures subjected to two independent biaxial loads. A maximum improvement of 71.2%% is achieved for shakedown load factor of the structure, which means a remarkable improvement in load bearing capacity of the structure.
6. Verifying Secure Authentication Protocol for Communication between IoT-based Medical Devices

Author:Theera-Umpon, N;Han, KH;Bae, WS;Lee, S;Pham, V

Source:JOURNAL OF UNIVERSAL COMPUTER SCIENCE,2018,Vol.24

Abstract:The evolving Internet of Things (IoT) technology has driven the advancement of communication technology for implantable devices and relevant services. Still, concerns are raised over implantable medical devices (IMDs), because the wireless transmission section between patients and devices is liable to intrusions on privacy attributable to hacking attacks and resultant leakage of patients' personal information. Also, manipulating and altering patients' medical information may lead to serious leakage of personal information and thus adverse medical incidents. To address the foregoing challenges, the present paper proposes a security protocol that copes with a range of vulnerabilities in communication between IMDs and other devices. In addition, the proposed protocol encrypts the communication process and data to eliminate the likelihood of personal information being leaked. The verification highlights the safety and security of the proposed protocol in wireless communication.
7. A Covert Ultrasonic Phone-to-Phone Communication Scheme

Author:Shi,Liming;Yu,Limin;Huang,Kaizhu;Zhu,Xu;Wang,Zhi;Li,Xiaofei;Wang,Wenwu;Wang,Xinheng

Source:Lecture Notes of the Institute for Computer Sciences, Social-Informatics and Telecommunications Engineering, LNICST,2021,Vol.349

Abstract:© 2021, ICST Institute for Computer Sciences, Social Informatics and Telecommunications Engineering. Smartphone ownership has increased rapidly over the past decade, and the smartphone has become a popular technological product in modern life. The universal wireless communication scheme on smartphones leverages electromagnetic wave transmission, where the spectrum resource becomes scarce in some scenarios. As a supplement to some face-to-face transmission scenarios, we design an aerial ultrasonic communication scheme. The scheme uses chirp-like signal and BPSK modulation, convolutional code encoding with ID-classified interleaving, and pilot method to estimate room impulse response. Through experiments, the error rate of the ultrasonic communication system designed for mobile phones can be within 0.001 %% in 1 m range. The limitations of this scheme and further research work are discussed as well.
8. XJTLUIndoorLoc: A New Fingerprinting Database for Indoor Localization and Trajectory Estimation Based on Wi-Fi RSS and Geomagnetic Field

Author:Zhong, ZH;Tang, Z;Li, XX;Yuan, TC;Yang, Y;Wei, M;Zhang, YY;Sheng, RZ;Grant, N;Ling, CF;Huan, XT;Kim, KS;Lee, S

Source:2018 SIXTH INTERNATIONAL SYMPOSIUM ON COMPUTING AND NETWORKING WORKSHOPS (CANDARW 2018),2018,Vol.

Abstract:In this paper, we present a new location fingerprinting database comprised of Wi-Fi received signal strength (RSS) and geomagnetic field intensity measured with multiple devices at a multi-floor building in Xi'an Jiatong-Liverpool University, Suzhou, China. We also provide preliminary results of localization and trajectory estimation based on convolutional neural network (CNN) and long short-term memory (LSTM) network with this database. For localization, we map RSS data for a reference point to an image-like, two-dimensional array and then apply CNN which is popular in image and video analysis and recognition. For trajectory estimation, we use a modified random way point model to efficiently generate continuous step traces imitating human walking and train a stacked two-layer LSTM network with the generated data to remember the changing pattern of geomagnetic field intensity against (x, y) coordinates. Experimental results demonstrate the usefulness of our new database and the feasibility of the CNN and LSTMbased localization and trajectory estimation with the database.
9. Analysis of a Similarity Measure for Non-Overlapped Data

Author:Lee, S;Cha, J;Theera-Umpon, N;Kim, KS

Source:SYMMETRY-BASEL,2017,Vol.9

Abstract:A similarity measure is a measure evaluating the degree of similarity between two fuzzy data sets and has become an essential tool in many applications including data mining, pattern recognition, and clustering. In this paper, we propose a similarity measure capable of handling non-overlapped data as well as overlapped data and analyze its characteristics on data distributions. We first design the similarity measure based on a distance measure and apply it to overlapped data distributions. From the calculations for example data distributions, we find that, though the similarity calculation is effective, the designed similarity measure cannot distinguish two non-overlapped data distributions, thus resulting in the same value for both data sets. To obtain discriminative similarity values for non-overlapped data, we consider two approaches. The first one is to use a conventional similarity measure after preprocessing non-overlapped data. The second one is to take into account neighbor data information in designing the similarity measure, where we consider the relation to specific data and residual data information. Two artificial patterns of non-overlapped data are analyzed in an illustrative example. The calculation results demonstrate that the proposed similarity measures can discriminate non-overlapped data.
10. EMG Pattern Classification by Split and Merge Deep Belief Network

Author:Shim, HM;An, H;Lee, S;Lee, EH;Min, HK;Lee, S

Source:SYMMETRY-BASEL,2016,Vol.8

Abstract:In this paper; we introduce an enhanced electromyography (EMG) pattern recognition algorithm based on a split-and-merge deep belief network (SM-DBN). Generally, it is difficult to classify the EMG features because the EMG signal has nonlinear and time-varying characteristics. Therefore, various machine-learning methods have been applied in several previously published studies. A DBN is a fast greedy learning algorithm that can identify a fairly good set of weights rapidly-even in deep networks with a large number of parameters and many hidden layers. To reduce overfitting and to enhance performance, the adopted optimization method was based on genetic algorithms (GA). As a result, the performance of the SM-DBN was 12.06%% higher than conventional DBN. Additionally, SM-DBN results in a short convergence time, thereby reducing the training epoch. It is thus efficient in reducing the risk of overfitting. It is verified that the optimization was improved using GA.
11. Privacy-Preserving Logistic Regression as a Cloud Service Based on Residue Number System

Author:Cortés-Mendoza,Jorge M.;Tchernykh,Andrei;Babenko,Mikhail;Pulido-Gaytán,Luis Bernardo;Radchenko,Gleb;Leprevost,Franck;Wang,Xinheng;Avetisyan,Arutyun

Source:Communications in Computer and Information Science,2020,Vol.1331

Abstract:The security of data storage, transmission, and processing is emerging as an important consideration in many data analytics techniques and technologies. For instance, in machine learning, the datasets could contain sensitive information that cannot be protected by traditional encryption approaches. Homomorphic encryption schemes and secure multi-party computation are considered as a solution for privacy protection. In this paper, we propose a homomorphic Logistic Regression based on Residue Number System (LR-RNS) that provides security, parallel processing, scalability, error detection, and correction. We verify it using six known datasets from medicine (diabetes, cancer, drugs, etc.) and genomics. We provide experimental analysis with 30 configurations for each dataset to compare the performance and quality of our solution with the state of the art algorithms. For a fair comparison, we use the same 5-fold cross-validation technique. The results show that LR-RNS demonstrates similar accuracy and performance of the classification algorithm at various thresholds settings but with the reduction of training time from 85.9%% to 96.1%%.
12. Design and compensation of second-order sub-sampling digital frontend

Author:Wang, HM;Kim, JH;Lee, SH;Kim, HJ;Kim, JU;Koh, JS

Source:JOURNAL OF CENTRAL SOUTH UNIVERSITY,2012,Vol.19

Abstract:The problem of designing a digital frontend (DFE) was considered which can dynamically access or sense dual bands in any radio frequency (RF) regions without requiring hardware changes. In particular, second-order bandpass sampling (BPS) as a technique that enables to realize the multiband reception function was discussed. In a second-order BPS system, digital reconstruction filters were utilized to eliminate the interferences generated while down converting arbitrarily positioned RF-band signals by using the direct digitization method. However, the inaccuracy in the phase shift or the amplitude mismatch between the two sample streams may cause insufficient rejection of interference. Practical problems were studied, such as performance degradation in signal-to-interference ratio (SIR) and compensation methods to overcome them. In order to demonstrate the second-order BPS as a flexible DFE suitable for software-defined radio (SDR) or cognitive radio (CR), a DFE testbed with a reconfigurable structure was implemented. Moreover, with a view to further demonstrate the proposed compensation algorithms, experimental results show that dual bands are received simultaneously.
13. Design Similarity Measure and Application to Fault Detection of Lateral Directional Mode Flight System

Author:Park, W;Lee, S;Lee, S;Ting, TO

Source:ADVANCES IN SWARM INTELLIGENCE, ICSI 2012, PT II,2012,Vol.7332

Abstract:In this work, we first obtained the similarity measures. The obtained similarity measures were designed based on well-known Hamming distance. It was also considered by analyzing the certainty and uncertainty of the fuzzy membership functions. The proposed similarity measure was applied to the fault detection of primary control surface stuck of Uninhabited Aerial Vehicle (UAV). At post-failure control surface, if the UAV has controllable and trimmable using other control surfaces, the UAV is able to fly or returns to the safety region through reconfiguration of the flight control system. By the calculation of similarity measure, result could be applicable with the real-time parameter estimation method. Furthermore, coefficients monitoring make it possible to monitor the occurrence of control surface fault. The obtained result has the advantage of increasing reliability without adding sensors or any additional cost.
14. Enhanced Protein Adsorption in Fibrous Substrates Treated with Zeolitic Imidazolate Framework-8 (ZIF-8) Nanoparticles

Author:Fu, H;Ou, PF;Zhu, J;Song, PF;Yang, JQ;Wu, Y

Source:ACS APPLIED NANO MATERIALS,2019,Vol.2

Abstract:Development for new solid substrates for protein adsorption is important, given the massive potential in a number of fields including food production, medicine, biotechnology, and pharmaceutical processing. We developed a zeolitic imidazolate framework 8 (ZIF-8)-nanoparticles based fibrous platform (Platform 1). Its ability in protein adsorption is proven by fluorescence study of Alexa Fluor 647-labeled donkey anti-rabbit IgG adsorbed on Platform 1. Studies reveal that Platform 1 shows much more enhanced protein adsorption compared to a polyethylene terephthalate gauze fibrous platform treated with ZIF-8 nanoparticles. This may be explained by considering that more active sites are enabled on fabric to adsorb a higher amount of ZIF-8 nanoparticles. We show that Platform 1 provides favorable biocompatibility to maintain the bioactivity of enzymes. Furthermore, we prove that a carboxymethylated cotton fabric platform treated with ZIF-8 (Platform 3) can be more capable of immobilizing the Alexa Fluor 647-labeled antibodies than Platform 1. Carboxymethylation helps to enhance protein adsorption in these cotton fabric substrates.
15. Influence of electrohydrodynamic jetting parameters on the morphology of PCL scaffolds

Author:Liu, H;Vijayavenkataraman, S;Wang, DD;Jing, LZ;Sun, J;He, K

Source:INTERNATIONAL JOURNAL OF BIOPRINTING,2017,Vol.3

Abstract:One of the important constituents in tissue engineering is scaffold, which provides structural support and suitable microenvironment for the cell attachment, growth and proliferation. To fabricate micro/nano structures for soft tissue repair and three-dimensional (3D) cell culture, the key is to improve fibre-based scaffold fabrication. Electrohydrodynamic (EHD) jetting is capable of producing and orientating submicron fibres for 3D scaffold fabrication. In this work, an EHD jetting system was developed to explore the relationship between vital processing parameters and fibre characteristics. In this study, polycaprolactone (PCL) solution prepared by dissolving PCL pellets in acetic acid was used to fabricate the scaffolds. The influence of voltage, motorized stage speed, solution feed rate, and solution concentration on fibre characteristics and scaffold pattern were studied. Morphology of the EHD jetted PCL fibres and scaffolds were analysed using optical microscope images and scanning electron microscope (SEM) images. Multi-layer scaffolds with the varied coiled pattern were fabricated and analysed. Cell attachment and proliferation have to be investigated in the future by further cell culture studies on these multi-layer coiled scaffolds.
16. Microscale scaffolds with diverse morphology via electrohydrodynamic jetting for in vitro cell culture application

Author:Wang, DD;Jing, LZ;Liu, H;Huang, DJ;Sun, J

Source:BIOMEDICAL PHYSICS & ENGINEERING EXPRESS,2019,Vol.5

Abstract:Microscale scaffolds have been intensively used in tissue engineering for cell culture. Traditionally, top-down approach like solvent casting, gas foaming and freeze drying to fabricate the scaffolds suffer from the drawback of variable microstructures of the scaffolds, pore sizes, and specific surface areas, which are important factors for reproducible cell culture application. To overcome these problems, bottom-up approach which builds up from single component has been preferred for manufacturing of scaffolds. One such technology is electrohydrodynamic jetting (EHDJ), which can produce controllable fiber diameter and orientation. Herein, we reported our progress on new design and printing of polycaprolactone (PCL) scaffolds with linear, serpentine, and hybrid structures. These are achieved by altering fabrication parameters using EHDJ technique. The three scaffolds exhibit high resolution and small pore structures suitable as support for 3D cell cultures as demonstrated by using fibroblast cells. Our results showed that although the hybrid scaffold has lower porosity than the line scaffold, more cells are found on the hybrid scaffold attributed to improved cell attachment and proliferation. Taken together, our results pave the road for design and printing of similar scaffolds with high resolution and precision controlled structural morphologies for in vitro cell culture and tissue engineering.
17. Space exploration of multi-agent robotics via genetic algorithm

Author:Ting,T. O.;Wan,Kaiyu;Man,Ka Lok;Lee,Sanghyuk

Source:Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics),2012,Vol.7513 LNCS

Abstract:Robots play an important role in space exploration whereby the presence of human is almost impossible in some environments. Instead of using a robot, we incorporate a group of robots working together to achieve the definitive goal. Evolutionary algorithm, namely Genetic Algorithm is applied in the multi-agent robotics for space exploration. Hereby, the core focus of this paper is to study the effect of crossover rate upon the convergence of the exploration. As from our results, choosing the right parameter value is crucial for optimal coverage of the potential area. © IFIP International Federation for Information Processing 2012.
18. A Nanocellulose-Paper-Based SERS Multiwell Plate with High Sensitivity and High Signal Homogeneity

Author:Chen, LY;Ying, BB;Song, PF;Liu, XY

Source:ADVANCED MATERIALS INTERFACES,2019,Vol.6

Abstract:Paper-based surface-enhanced Raman scattering (SERS) substrates have gained growing interest as an eco-friendly and low-cost tool for chemical and biosensing. However, paper-based SERS substrates often suffer relatively low signal spatial homogeneity because of their nonuniform hot-spot distribution. In this paper, a nanofibrillated cellulose paper (nanopaper) based SERS multiwell plate is developed for trace chemical detection with high sensitivity and high signal homogeneity. The SERS plate is fabricated from ultrasmooth (2,2,6,6-tetramethylpiperidin-1-yl)oxyl-oxidized NFC paper (TO-nanopaper) through wax-printing-based multiwell patterning followed by silver nanoparticle (AgNP) growth based on a successive ionic layer adsorption and reaction (SILAR) process. Taking advantage of the abundance of carboxyl groups on the TO-nanopaper, uniformly distributed and densely arranged AgNPs are successfully synthesized through the SILAR process on the NFC multiwell surface under ambient conditions. The SERS performance of the device is evaluated for testing two Raman marker chemicals, rhodamine B and 2-naphthalenethiol, and picomolar detection limit and high Raman enhancement factor (up to 1.46 x 10(9)) are achieved. The Raman signal mapping results show superior signal spatial homogeneity of the device with low variations (<= 11%%). The nanopaper-based SERS device represents a promising SERS platform for chemical and biomolecule detections with high sensitivity and high repeatability.
19. Power Spectral Deviation-Based Voice Activity Detection Incorporating Teager Energy for Speech Enhancement

Author:Kim, SK;Kang, SI;Park, YJ;Lee, S;Lee, S

Source:Symmetry-Basel,2016,Vol.8

Abstract:In this paper, we propose a robust voice activity detection (VAD) algorithm to effectively distinguish speech from non-speech in various noisy environments. The proposed VAD utilizes power spectral deviation (PSD), using Teager energy (TE) to provide a better representation of the PSD, resulting in improved decision performance for speech segments. In addition, the TE-based likelihood ratio and speech absence probability are derived in each frame to modify the PSD for further VAD. We evaluate the performance of the proposed VAD algorithm by objective testing in various environments and obtain better results that those attained by of the conventional methods.
20. Smart Image Enhancement Using CLAHE Based on an F-Shift Transformation during Decompression

Author:Fan, RQ;Li, XY;Lee, S;Li, TL;Zhang, HL

Source:ELECTRONICS,2020,Vol.9

Abstract:As technologies for image processing, image enhancement can provide more effective information for later data mining and image compression can reduce storage space. In this paper, a smart enhancement scheme during decompression, which combined a novel two-dimensional F-shift (TDFS) transformation and a non-standard two-dimensional wavelet transform (NSTW), is proposed. During the decompression, the first coefficient s(00) of the wavelet synopsis was used to adaptively adjust the global gray level of the reconstructed image. Next, the contrast-limited adaptive histogram equalization (CLAHE) was used to achieve the enhancement effect. To avoid a blocking effect, CLAHE was used when the synopsis was decompressed to the second-to-last level. At this time, we only enhanced the low-frequency component and did not change the high-frequency component. Lastly, we used CLAHE again after the image reconstruction. Through experiments, the effectiveness of our scheme was verified. Compared with the existing methods, the compression properties were preserved and the image details and contrast could also be enhanced. The experimental results showed that the image contrast, information entropy, and average gradient were greatly improved compared with the existing methods.
Total 127 results found
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