2017 28th Irish Signals and Systems Conference (ISSC)最新文献

{"title":"Observations of the differences between closed-loop behavioral and feed-forward model simulations of fractional-N frequency synthesizers","authors":"Dawei Mai, Hongjia Mo, Michael Peter Kennedy","doi":"10.1109/ISSC.2017.7983621","DOIUrl":"https://doi.org/10.1109/ISSC.2017.7983621","url":null,"abstract":"Conventionally, a fractional-N synthesizer is simulated using a closed-loop behavioral model and the simulations can be very time-consuming. With the analysis by Perrott et al., a more straightforward model, namely the feed-forward model, for the fractional-N frequency synthesizer is available. The feedforward model simulations provide quick, relatively accurate evaluation of fractional-N synthesizer divider controller designs. In this work, we point out several differences in the closed loop behavioral model simulations performed in the CppSim environment and the feed-forward model simulations and discuss their significance on the base of analysis and simulation results.","PeriodicalId":170320,"journal":{"name":"2017 28th Irish Signals and Systems Conference (ISSC)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116965758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Predicting short-term wholesale prices on the Irish single electricity market with artificial neural networks","authors":"Pengfei Li, Francesco Arci, Jane Reilly, Kevin Curran, A. Belatreche, Yauheniya Shynkevich","doi":"10.1109/ISSC.2017.7983623","DOIUrl":"https://doi.org/10.1109/ISSC.2017.7983623","url":null,"abstract":"The ability to operate effectively on electricity spot markets relies on the capability to devise appropriate bidding strategies. These in turn can benefit from the inclusion of a reliable forecast of short term system marginal prices (SMPs). In a market with an increasing percentage of renewable generators, reliable forecasts must necessarily consider additional factors such as meteorological forecasts, forecasted demand and constraints imposed by network topology. Traditional time series forecasting algorithms (e.g. based on AutoRegressive Integrated Moving Average models) can perform reasonably well in this context but rely on assumptions being made on behavior over different temporal windows to yield consistent results. Research studies have demonstrated that an adaptive or self-adaptive approach to forecasting would appear more suited to the task of predicting energy demands in territory such as Ireland. Implementing an in-house self-adaptive model should yield good results in the dynamic uncertain Irish energy market. We have identified the features that such a model demands and outline it here.","PeriodicalId":170320,"journal":{"name":"2017 28th Irish Signals and Systems Conference (ISSC)","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121898764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Design of voltage regulators for automotive applications: A sensitivity-driven approach","authors":"P. Napolitano, K. Kelliher","doi":"10.1109/ISSC.2017.7983617","DOIUrl":"https://doi.org/10.1109/ISSC.2017.7983617","url":null,"abstract":"In this paper, a mathematical framework is presented, helping in the identification and selection of the components that mostly affect performance in monolithic voltage regulators. A sensitivity analysis is proposed, showing how the loop transfer function depends on the values of the components used in the compensator. The theory has been validated through behavioral and transistor level simulations, considering a single-phase interleaved buck converter operated in voltage mode at 2-MHz switching frequency, supplied by a 5-V input and generating a 1-V regulated output. The presented results can be extended to other regulators exploiting Type II and Type III internal compensators.","PeriodicalId":170320,"journal":{"name":"2017 28th Irish Signals and Systems Conference (ISSC)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125987737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A linearised PV maximum power tracking controller for AC network integration analysis","authors":"Colin Levis, M. Hill","doi":"10.1109/ISSC.2017.7983631","DOIUrl":"https://doi.org/10.1109/ISSC.2017.7983631","url":null,"abstract":"The maximum power available from a photovoltaic (PV) generator in many grid connected systems is extracted using a dc-dc step up converter that implements a maximum power point tracking (MPPT) algorithm. Traditional MPPT algorithms are iterative, continuously searching for the maximum power point (MPP) under varying weather conditions. Due to the nonlinear time-varying nature of commonly used MPPT methods such as perturb and observe (P&O) it is not easily integrated into state-space models for AC network analysis. In this paper a linearised PV MPPT controller for AC network integration analysis is presented. The non-linear step up converter and PV array are transformed into a time invariant system by using the state space sliding averaging technique, over a single switching cycle. This allows for linear controller design and provides a computationally inexpensive model suitable for AC network integration analysis. The linearised controller robustness was assessed over the expected operating irradiance range, at a constant temperature, using the detailed switching model in MATLAB/Simulink which produced increased performance and stability when compared to P&O MPPT. The computational time using a standard operating system for a 2s simulation of the detailed switching model was 263s while the reduced small signal model was 0.4s.","PeriodicalId":170320,"journal":{"name":"2017 28th Irish Signals and Systems Conference (ISSC)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127945238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Maximization of sum rate in AF-cognitive radio networks using superposition approach and n-out-of-k rule","authors":"Md. Sipon Miah, M. Schukat, E. Barrett","doi":"10.1109/ISSC.2017.7983602","DOIUrl":"https://doi.org/10.1109/ISSC.2017.7983602","url":null,"abstract":"The spectrum sensing strategy plays a vital role in Amplify-Forward (AF)-Cognitive Radio Networks (CRNs). However, AF-CRN cannot obtain maximal throughput, when existing sensing strategies are applied to AF-CRNs. In this paper, we present a superposition approach in AF-CRNs, in which firstly a Secondary User (SU) extends its sensing time until right before the beginning of its reporting time slot, and secondly each SU sends its measurement results containing amplified reports to the Cluster Head (CH), while the CH with soft-fusion report is forwarded to the Fusion Center (FC). With such extended sensing intervals and amplified reporting, a better sensing performance can be obtained than with the conventional rigid strategy. In addition to this, the sum rate of primary and secondary networks is also investigated for the superposition approach and the n-out-of-k rule. Numerical experiments show that the proposed strategy guarantees maximum sum rate compare to the conventional strategy under any condition.","PeriodicalId":170320,"journal":{"name":"2017 28th Irish Signals and Systems Conference (ISSC)","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121450695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identity document authentication using steganographic techniques: The challenges of noise","authors":"Juanita Blue, J. Condell, T. Lunney","doi":"10.1109/ISSC.2017.7983646","DOIUrl":"https://doi.org/10.1109/ISSC.2017.7983646","url":null,"abstract":"The term ‘steganography’ encapsulates the practice of secretly embedding data into digital mediums including video, image and audio files. Although steganography is often associated with nefarious activities, conceptually it asserts several characteristics that render it useful in contemporary security applications. Not just a mechanism for criminals to communicate secret information over a digital channel, steganography is also used as a legitimate method of ensuring integrity of digital media artefacts and for identification of same. This application of steganography allows for identification images storing additional information to verify both the identity of the subject as well as the authenticity of the image. Developed methods of steganography invoke various spatial domain techniques that are successful in covertly concealing data within ‘innocent’ carrier images. The techniques include linear methods such as those which replace the least significant bit (LSB) of the bytes in an image and frequency domain methods including discrete cosine transform (DCT), discrete wavelet transform (DWT) and discrete Fourier transform (DFT). The success of a steganographic algorithm is hinged on the method's ability to successfully embed data, so that the data remains concealed within a carrier image; and also to successfully extract the same data uncorrupted. Often modern image coding formats include lossy compression in the frequency domain; this can result in data loss, corruption and noise within the image when carrier images are re-encoded. To ensure data extraction is successful, error correction functions must be invoked to counteract noise and ensure embedded data is extracted without any loss or corruption. In exploring steganographic software, the functionality and reliability of a novel steganographic application ‘Intelligent Identity Authenticator’ (IIA) was assessed. IIA invokes the use of steganography to conceal real-time identity information within images on identity cards. The functionality of IIA is based on a unique algorithm that utilizes DWT to embed a string of characters within an identity image. When data is extracted, it provides a link to further documentation relating to the data subject, allowing for verification of the claimant's identity and authenticity of the identity card. The embedding and extraction functions executed by IIA were found to be mostly reliable, except where data had been embedded within a carrier image that was characterized by a large proportion of black pixels. In these cases, the extracted data string experienced significant loss and corruption, thus preventing access to the identity verification documentation. This paper explores the potential cause of this specific corruption and discusses extensive testing conducted on control images. The results are analysed to identify an improved solution that could rectify the issue, with an aim to improving both the functionality and reliability of the IIA system.","PeriodicalId":170320,"journal":{"name":"2017 28th Irish Signals and Systems Conference (ISSC)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121841804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Voice conversion based on continuous frequency warping and magnitude scaling","authors":"Yuhang Ye, B. Lawlor","doi":"10.1109/ISSC.2017.7983598","DOIUrl":"https://doi.org/10.1109/ISSC.2017.7983598","url":null,"abstract":"In this paper, we present a novel spectrum mapping method — Continuous Frequency Warping and Magnitude Scaling (CFWMS) for voice conversion under the Joint Density Gaussian Mixture Model (JDGMM) framework. JDGMM is a mature clustering technique that models the joint probability density of speech signals from paired speakers. The conventional JDGMM-based approaches morph the spectral features via least square optimization. However, the speech quality is degenerated as the converted features are blurred by statistical smoothing and the uncorrelated conversion functions between adjacent frames cause noticeable distortion. To this end, CFWMS proposes a twofold frame-level conversion method — Frequency Warping and Magnitude Scaling (FWMS). FWMS directly operates on signals in the frequency domain without statistical smoothing. Moreover, a trajectory limitation strategy is introduced to renovate the discontinuities between adjacent frames. Note that the proposed solution does not require global information of sentences, making it feasible for low latency (e.g. real-time) applications. The experimental results show significantly improvements in terms of the speech quality and the perceptual identity.","PeriodicalId":170320,"journal":{"name":"2017 28th Irish Signals and Systems Conference (ISSC)","volume":"2500 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131239095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Methodology for automated and recursive verification of verilog-AMS models against schematic","authors":"Stephen Ogunniran, P. Napolitano, K. Kelliher","doi":"10.1109/ISSC.2017.7983635","DOIUrl":"https://doi.org/10.1109/ISSC.2017.7983635","url":null,"abstract":"In this paper, a Verilog-AMS based methodology for automated verification is discussed. This solution is geared towards aiding the verification of behavioral models, which designers are tasked with when developing or editing a schematic. Up to now the conventional way to verify the operation of a model and how much it mimics the operation of a schematic is to visually inspect the output signals between models and schematics. The proposed methodology compares the signals and outputs a digital bit, indicating if the difference between schematic and model falls within the user defined tolerance range. The solution also prints a pass/fail error messages into a log file which can be easily reviewed by the designer. As a result a more accurate and user friendly platform is presented for verification, saving a significant amount time during the top level verification phase of a project.","PeriodicalId":170320,"journal":{"name":"2017 28th Irish Signals and Systems Conference (ISSC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130360171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fast volume calibration and occlusion free depth estimation using enhanced optical orthogonal codes","authors":"Lakshmi Sravya Koppula, I. Kiran, K. Venkatesh","doi":"10.1109/ISSC.2017.7983606","DOIUrl":"https://doi.org/10.1109/ISSC.2017.7983606","url":null,"abstract":"Structured light techniques have received increased attention for depth estimation as they are robust and accurate. In this paper, we propose a method for camera-projector calibration which is required for structured light based depth estimation. We also propose enhancements to the existing hierarchical orthogonal coding (HOC) technique. The proposed space calibration technique is simple and fast compared to current camera-projector calibration techniques. The existing HOC, though being robust to ambient environmental lighting conditions, fails at occluded regions due to its pixel decoding strategy. With this in mind, we propose a self occlusion detection method to detect such ‘shadows’ in advance and to recommend to readjust the camera-projector positions to eliminate the shadows. Additionally an address transition rule is also proposed to correct any erroneously detected code. The proposed method is evaluated by computing the depth maps of objects of different known shapes.","PeriodicalId":170320,"journal":{"name":"2017 28th Irish Signals and Systems Conference (ISSC)","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123384339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigating stimuli graphics' size and resolution performance in Steady State Visual Evoked Potential","authors":"A. Szalowski, D. Picovici","doi":"10.1109/ISSC.2017.7983618","DOIUrl":"https://doi.org/10.1109/ISSC.2017.7983618","url":null,"abstract":"This paper investigates brain signal peaks and their relationship to flicker size and resolution using colour red-white (RW) and monochrome black-white (BW) graphics. The raw electroencephalograph (EEG) signals were recorded using Emotiv EPOC headset into Windows based PC running Emotiv Xavier Test Bench software. The flickers oscillating at 10 Hz of different resolutions were displayed over black and white backgrounds using iPad Pro 12.9” tablet. The signals were analysed and their amplitude and noise levels were measured using MATLAB with EEGLAB and ERPLAB plugins. Flickers with white background elicited better signals. Red and white colour combination for flicker checkerboard outperformed the standard black and white design. Decreasing the flickers' size yielded gradual increase in elicited signal peaks.","PeriodicalId":170320,"journal":{"name":"2017 28th Irish Signals and Systems Conference (ISSC)","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126211880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}