| | | | | P | 0 - 2.5 | 0.08 - 0.10 | Q | 0 - 3 | 0.06 - 0.10 | R | 6 - 21 | S | 0 - 6 | T | 0 - 5 | 0.10 - 0.25 | Of course, there are many other natural and artificial, intentional and unintentional causes of ECG variability. For example, taking certain medications may temporarily change the configuration of the cardiac cycle. Some pathologies over time gradually change the form of the cardiac cycle. Moreover, human actions during the ECG recording can significantly distort or change the signal. Thus, an ECG identification system will face a variety of challenges that are similar to those posed by various attacks on other types of biometric systems. Identification system synthesisThe generic system structure (figure 5, left) shows the sequence of essential data processing stages. Feedforward links show processed data transfer between stages. The output of one stage is the input to the subsequent stage. Each stage can be implemented using different processing methods. The detailed system structure (figure 5, right) shows methods considered in this study for each system stage. For most stages, these methods are alternatives, but the data preprocessing stage is usually comprised of several complementary methods. Identification system synthesis is a process of selection between alternative methods, determination of composition and sequence of complementary methods, and adjustment of parameters for all methods in such a way as to obtain the best results. It is almost impossible to perform an exhaustive search. In this study, a strategy of result-directed backtracking was applied. Multiple feedback links in the detailed structure scheme show that results obtained on one stage can influence decisions made in previous stages. In other words, usefulness of some changes in data processing on one stage can be evaluated by comparing the results of one of the following stages obtained before and after these changes. This empirical technique doesn't guarantee optimal results, but it yields more or less reasonable method selections without requiring excessive computation. Data acquisitionExperimental studies involved 90 volunteers. ECG records were made in the sitting position. Heart rate, physical and emotional state were not limited. For usability, it is necessary to be able to collect the ECG easily and quickly. The procedure for ECG acquisition should be convenient for individuals and should require interaction with a minimal set of equipment; therefore it was decided to use single-lead ECG. Since single-lead ECGs vary significantly within an individual depending on the lead (the locations of the electrodes used to observe the ECG), the choice of lead is important. Lead I is the potential difference between the left and right hands (LA - RA). It was chosen because it is easily measured and it is not sensitive to minor variations in electrode locations. Limb clamp electrodes were used. This type of skin-electrode contact closely imitates the likely scenarios of user interaction with a practical identification system. The data collected for this study comprise the ECG-ID Database , consisting of 310 I-lead ECG recordings from 90 individuals, each 20 seconds long, sampled at 500 Hz with 12-bit precision. To train and test the identification system, the collected data were divided into two sets. 195 records were assigned to the training set and 115 records to the test set. Differentiation between the training and test sets aimed to provide for maximum performance complexity, i.e., maximum difference between records in different sets both in monitoring time and human physical state. Data preprocessing | Wavelet decomposition: wname = 'db8', N = 9. | | Ws = 50 Hz, dA = 1.5. | | Butterworth filter, Wp = 40 Hz, Ws = 60 Hz, Rp = 0.1 dB, Rs = 30 dB. | | N = 5. | Initial feature space formationInitial feature space formation is a key stage of the identification system. Although decisions made in other stages significantly influence the final identification results, feature selection determines the potential performance of the identification system most of all. 1. | Correcting PQRST-fragment mutual "vertical" shift due to residual baseline drift. Mean values of all PQRST-fragments were subtracted, so that the corrected segments had mean values of zero. | | | 2. | Culling PQRST-fragments that are distorted due to breathing or motion artifacts, as well as pathological PQRST-fragments. From the set of 10 extracted PQRST-fragments, the "mean" PQRST-fragment was estimated (red line); using Euclidean distance, only the 6 closest PQRST-fragments were selected (blue lines) for further analysis. | | | 3. | Correcting PQRST-fragments depending on heart rate. The ST-fragment (samples from the end of the S wave to the end of the T wave) of PQRST-fragment was scaled using QT interval correction formulas. The Framingham and Bazett's formulas were considered; use of the Framingham formula gave better and more robust results. | | | Thus in the initial feature space (dimension N =250) the ECG appears as a set of 6 PQRST-fragments with each seen as a separate pattern at subsequent system stages, to be interpreted and classified independently. Feature space reductionInitially, the feature space dimension (or number of features for each pattern) is quite large ( N =250). This fact may make subsequent processing difficult or computationally impossible. The initial features, however, may include redundant and useless information due to correlation and interdependencies between features. In other words, the informational content of each initial feature and its contribution to the distinction of classes vary significantly. The feature space reduction procedure aims to make the transition from the initial feature space, with a correlated basis, into a new feature space with an uncorrelated basis. This procedure allows significant dimensionality reduction with minimal information loss. To compare the initial and reduced feature spaces quantitatively, intra- and interclass metrics were considered. Usually, the class centroid is defined as the mean of all class points, so that the intraclass distance can be defined as the mean distance between the class points and the class centroid, and interclass distance as the distance between class centroids. Conceptually, intraclass distance characterizes the volume of the class or ECG variation within an individual, and interclass distance characterizes the separation of classes from each other or ECG variation between individuals. Obviously, good classification results can be achieved when interclass distances are significantly greater than intraclass distances. In the figure, it is clear that feature space reduction slightly increases intraclass distances. More important, however, it noticeably improves class separability, increasing both minimal and mean interclass distances. In other words, classes in reduced feature space gain some extra volume, but are more clearly separated from each other. Overlap between the plots of intraclass distances and minimal interclass distances indicates the presence of some collisions (ambiguities) in the classification. Significant separation of plots of intraclass distances and mean interclass distances indicates that, potentially, classification can achieve high performance. Of course, it is difficult to predict how the feature space will be filled with new classes (i.e., as the system is required to identify a larger number of individuals), but judging by the ratio of distances there is the potential to increase this number without losing the classification quality. Classification and IdentificationAs a result of data processing on previous stages, the original ECG record is represented as a set of six PQRST-fragment patterns in the reduced feature space. At this stage, each PQRST-fragment pattern is classified independently of the others and assigned to some class, and each PQRST-fragment classification result is a vote for the candidate class of the final ECG record identification, which is elected by a majority of votes. The figure shows that the results obtained are consistent with expectations. Indeed, the Nearest Mean Classifier provides quite good results. Figure 14 shows that classes typically have elongated shapes, i.e., that the variances of the different features are not equal, so that the Weighted Nearest Mean Classifier provides better results. Linear Discriminant Analysis not only provides the best recognition result in the test set, but also minimizes the recognition error in the training set. ECG record identification rate is higher than the PQRTS-fragments recognition rate, since a pair of misclassified PQRTS-fragments do not affect the correctness of the ECG record identification. As a result of this research, a recognition system was developed to solve the problem of biometric human identification based on ECG on a sufficiently large set of input data. The findings support the use of ECG as a new biometric characteristic in various biometric access control problems. Of course, it is doubtful that ECG is unique enough to be feasible for identification of large numbers of individuals in a general population. More likely, it can be useful for identification within relatively small predetermined groups, or as an additional feature in multi-variable biometric identification systems. Thus, it opens up a brand new perspective for the study of biometric technologies with potential applications in security and modern life amenity systems. | | | | | | 20 (20-55 years) | 9 (22-28 years) | 20
| 90 (13-75 years) | | 12 leads | Wireless, 30 minutes long | Lead I | Lead I, 20 seconds long | | 135 records, different days | 18 records, different days | 20 records | 210 records, different days during 6 months | | 4-10 records | 2 records | 1 record | 2-20 records | | 85 records | 9 records of one day, 30 fragments for each record | 20 heartbeats for each record | 195 records, 6 of 10 heartbeats for each record | | 50 records | 9 records of another day, all fragments for each record | 1 heartbeat for each ECG (different part) | 115 records, 6 of 10 heartbeats for each record | | Heartbeat waves amplitudes and intervals duration ( =30) | Coefficients of the wavelet decomposition of successive ECG fragments 10 seconds long | QRS complex and T wave amplitudes and intervals duration ( =7) | Samples of cardiac cycle fragment containing the QRS complex, P and T waves ( =250) | | - | Principal Component Analysis | - | Principal Component Analysis or Wavelet Transform | | Soft Independent Modeling of Class Analogy (Multivariate Analysis) | Probabilistic neural network | Template matching (TM), Decision-based neural network (DBNN) | Linear Discriminant Analysis and Majority Vote Classifier | | 98 % | 95 % | TM: 95 %, DBNN: 80 %, Both: 100 % | 96 % | [1] Biel L., Pettersson O., Philipson L., Wide P. ECG analysis: a new approach in human identification. IEEE Transactions on Instrumentation and Measurement 2001 June; 50(3):808-812. [2] Yi WJ, Park KS, Jeong DU. Personal identification from ECG measured without body surface electrodes using probabilistic neural networks. Proc 2003 World Congress on Medical Physics and Biomedical Engineering, Sydney, Australia, 2003 August. [3] T.W. Shen, W.J. Tompkins, Y.H. Hu. One-lead ECG for identity verification. Proc. of the 2nd Joint Conference of the IEEE Engineering in Medicine and Biology Society and the Biomedical Engineering Society, vol. 1, pp. 62-63, 2002. Your comments and suggestions are welcome. Please send them to .
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DESIGNING AN EFFECTIVE RECORDS MANAGEMENT SYSTEM A CASE STUDY OF THE ECONOMIC POLICY RESEARCH CENTER (EPRC) UGANDA January 2013 DOI: 10.13140/RG.2.2.35178.67522 Thesis for: Bachelors of Records ...
EFFECTIVENESS OF RECORDS MANAGEMENT PRACTICES IN THE DEPARTMENT OF PHYSICAL WORKS PLANNING AND ESTATES AT NUST May 2014 DOI: 10.13140/2.1.2550.8647 Thesis for: Records and Archives Management
gement is the gist of an organization because it is through records that an institution can provide a documentation of activities and plans. Records provide valuable information for critical decision making within organizations. However, organizational managers fail to recognize the contribution of effective records management practices in public administration. Therefore, the aim of this ...
Abstract: This study aims to evaluate the implementation of the records management system of Cotabato Regional Medical Center Health Information Department. It utilized the quantitative-qualitative design in data gathering that was conducted in Cotabato Regional Medical Center, a tertiary hospital located in Cotabato City, to the 100 respondents composed of CRMC staff and personnel and clients ...
The literature review maintains that an effective records management program anchor on a written records management policies, standards and procedures. The researcher used a case study research design where a single department of NUST was chosen for this study.
this thesis is to question why records management is not considered high priority in many organisations? A government, particularly in a truly democratic country, is accountable to its people for its administration and governance. Public records, which are the bye-products of public organisations, provide evidence of the governance of the country.
Explore the latest full-text research PDFs, articles, conference papers, preprints and more on RECORDS MANAGEMENT. Find methods information, sources, references or conduct a literature review on ...
The contention of this thesis is that record keeping is just a tool that ensures the availability of evidence for the accountability of governance, which in turn relies on the ethical standard of those involved.
This Master thesis focuses on the concept of Records Management (RM) and Electronic Records Management (ERM) and how the adoption of an Electronic Document Records Management System (EDRMS) affects a business setting.
This Master thesis focuses on the concept of Records Management (RM) and Electronic Records Management (ERM) and how the adoption of an Electronic Document Records Management System (EDRMS) affects a business setting. The research focuses on the factors of perceived efficiency and on the costs that exist in a company. More specifically, this Master thesis is a qualitative exploratory case ...
the staff and organization as a whole. This study examined the perceived impact of records management strategies on administrative staff's professional performance. The st dy also explored the difference among records management strategies and professional performance in er job enure, and position in the depar 2.
Introduction Records Management (RM) is defined as the study of management that is important for the effective and systematic control of record creation, receipt, maintenance, use, and disposition, as well as the processes for capturing and maintaining evidence of and information about business activities and transactions in the form of records. Records are vital to the efficient and ...
ABSTRACT The study intended to focus on the effectiveness of records management systems in academic libraries, with a case study of Kampala International University. The study was focused on the types of records kept, values of records, records management systems. elements of records management systems, types of records management systems, effective records management system of print and non ...
A cost model approach to records management system in the civil service of Oyo State, Nigeria.Unpublished PhD Thesis, Department of Library, Archival and Information studies, University of Ibadan- Nigeria. fStrauss, A.L. and Corbin, J. (1998).Basics of qualitative research: techniques and procedures for developing grounded theory.
List of dissertations / theses on the topic 'Electronic Records Management'. Scholarly publications with full text pdf download. Related research topic ideas.
A survey was also conducted to examine the current records management practices at ADM and the data was collected by means of self-administered questionnaires. The literature study proved the hypothesis to be correct, which stated that effective records management plays a significant role in the effective administration of an organization.
Objectives Generally, this study was conducted to assess the records management practices in the province of Rizal. Specifically, it aimed to (1) dentify the profile of the barangay secretaries; (2) identify the existing records kept and managed in every barangay; (3) find out the different records management practices in every barangay; (4 ...
PDF | This paper has examined applicable theories on the records and archives management (RAM) in an attempt to use empirical results and findings to... | Find, read and cite all the research you ...
List of dissertations / theses on the topic 'Division of Records Management and Archives'. Scholarly publications with full text pdf download. Related research topic ideas.
Saint Petersburg State University DSpace at Saint Petersburg State University ECONOMICS & BUSINESS Management
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Lugovaya T.S. Biometric human identification based on electrocardiogram. [Master's thesis] Faculty of Computing Technologies and Informatics, Electrotechnical University "LETI", Saint-Petersburg, Russian Federation; June 2005.