Different Types Of Redundancy Research Articles

RELIABILITY ANALYSIS OF SWITCH’S CONTROL SCHEMES

Purpose. The purpose of this article is to conduct an analysis of the reliability of the control schemes of the electric arrow drive with the aim of optimizing and modernizing them to increase the reliability indicators. To show an approach to optimizing the control circuits of an electric turnout that is advantageous from an operational point of view, the implementation of fewer control circuits will minimize the number of failures. To demonstrate a principled circuit solution for optimizing the control circuit of an electric turner with the use of separate redundancy with always-on redundancy and integer multiplicity. Methods. During the research, methods of comparative analysis, synthesis, probability theory, and reliability theory were used. Findings. The paper analyzes the types of re-reservation as a way to increase the reliability of the arrow control scheme. A comparative study of the reliability of various options for reserving the turnout control scheme was carried out in comparison with the classic situation on the railways of Ukraine - the absence of a reserve. It has been proven that the use of separate redundancy with always-on reserve and integer multiplicity provides the maximum increase in reliability, but the significant amount of necessary equipment significantly reduces the economic attractiveness of this method. On the other hand, the use of separate redundancy with substitution and fractional multiplicity (sliding redundancy) gives a positive result only if one redundancy unit serves no more than 15 turnout electric drives, otherwise the overall reliability of the subsystem may decrease. The optimization of the arrow control subsystem at the station is proposed, which requires the use of only six arrow control schemes, one of which is a sliding reserve. The influence of different types of redundancy on the reliability indicators of the arrow control scheme is considered. The most effective option for optimizing the arrow control subsystem has been determined. Scientific novelty. The scientific novelty of the work consists in the well-founded sufficiency of using only six arrow control schemes in combination with the use of sliding redundancy of the arrow control scheme for the control of arrows when disbanding warehouses on the sorting slide. The proposed method makes it possible to increase the reliability of the arrow control subsystem while maintaining the operational parameters of the station. Practical significance. The practical significance of the results lies in the fact that when using the proposed optimization, the resource use of hill automation devices is improved, the maintenance process is simplified, and the total cost of equipment and maintenance costs are reduced.

Two types of redundancy in multimedia learning: a literature review.

Regarding the redundancy effect in multimedia learning environments, more consistency is needed in the theoretical assumptions and investigation of this effect. Current research lacks a comprehensive account of different redundant scenarios in which materials facilitate or inhibit learning and provides little conceptual guidance on how learning processes are affected by different types of redundancy. Theoretical assumptions refer to redundancy as a contentual overlap of information provided by the learning material; in this case, processing duplicated information strains the learners' limited cognitive capacities. Other assumptions refer to the role of processing limitations in working memory channels, including separate processing for visual and verbal information. In this case, an ineffective combination of sources leads to an overload of the limited working memory capacity. This paper reviews empirical research on the redundancy effect (63 studies) and classifies two types of redundancy: (1) content redundancy, and (2) working memory channel redundancy. From an instructional psychology perspective, the analyses reveal four different implementations of redundant scenarios: (1) adding narration to visualizations, (2) adding written text to visualizations, (3) adding written text to narration, and (4) adding written text to narrated visualizations. Regarding the effects of the two redundancy types within these scenarios, analyses indicate positive effects of content redundancy (affected by learners' prior knowledge), negative effects of working memory channel redundancy (regarding visualizations and written text), and positive effects of working memory channel redundancy (regarding narration and written text). Moreover, results point to factors that might moderate the effect of redundancy and illustrate interactions with existing multimedia effects. Overall, this review provides an overview of the state of empirical research and reveals that the consideration of both redundancy types provides further explanations in this field of research.

Different types of redundancy and their effect on learning and cognitive load.

What is redundancy? While most studies confirm that redundancy is harmful to learning, there are two theoretical approaches to redundancy. The first understands redundancy as a contentual overlap that puts demand on the limited cognitive capacities of the learner. The second understands redundancy as an ineffective combination of sources leading to an overload of the limited working memory modalities. Since these theoretical differences are rarely acknowledged in operation, this study proposes a classification of two distinct types of redundancy to compare these experimentally to investigate their possible main and interaction effects. The first type, content redundancy, is concerned with the contentual overlap of information. The second type, modal redundancy, is concerned with the modalities in which the information is displayed. We used these two types of redundancy as factors in a 2 × 2 within-subject design, in which we experimentally compared their effects. University students (N=46) learned from specifically designed domain-general material which aimed to observe redundancy effects without interference from confounding variables. The results show that content redundancy increases learning outcomes and decreases cognitive load, while modal redundancy decreases learning outcomes and increases cognitive load. On the theoretical level, these findings confirm the usefulness to distinguish content redundancy from modal redundancy. On the practical level, the empirical findings of the different effects of the two types of redundancy provide educators with important insights that can improve the design of multimedia learning materials.

Metaheuristic-based vector quantization approach: a new paradigm for neural network-based video compression

Video compression has great significance in the communication of motion pictures. Video compression techniques try to remove the different types of redundancy within or between video sequences. In the temporal domain, the video compression techniques remove the redundancies between the highly correlated consequence frames of the video. In the spatial domain, the video compression techniques remove the redundancies between the highly correlated consequence pixels (samples) in the same frame. Evolving neural-networks based video coding research efforts are focused on improving existing video codecs by performing better predictions that are incorporated within the same codec framework or holistic methods of end-to-end video compression schemes. Current neural network-based video compression adapts static codebook to achieve compression that leads to learning inability from new samples. This paper proposes a modified video compression model that adapts the genetic algorithm to build an optimal codebook for adaptive vector quantization that is used as an activation function inside the neural network’s hidden layer. Background subtraction algorithm is employed to extract motion objects within frames to generate the context-based initial codebook. Furthermore, Differential Pulse Code Modulation (DPCM) is utilized for lossless compression of significant wavelet coefficients; whereas low energy coefficients are lossy compressed using Learning Vector Quantization (LVQ) neural networks. Finally, Run Length Encoding (RLE) is engaged to encode the quantized coefficients to achieve a higher compression ratio. Experiments have proven the system’s ability to achieve higher compression ratio with acceptable efficiency measured by PSNR.

Multithreaded and Reconvergent Aware Algorithms for Accurate Digital Circuits Reliability Estimation

Until recently, reliability was not considered to be a major design concern for circuit designers, except in the case of space and mission critical applications. However, the aggressive scaling of CMOS devices has significantly affected their reliable operation. Several schemes have been used for mitigating the scaling effects and maintaining the reliability above a certain threshold. Many of these schemes rely on incorporating different types of redundancy at the device, gate, and system level, which inevitably affect the area, power, and delay parameters. To optimize the tradeoff between these conflicting parameters, an accurate and efficient reliability EDA tool is needed. Such a tool would help circuit designers compare different reliability schemes and select the one that achieves the target reliability margins while having minimum impact on the other design parameters. However, the enormous size and the complexity of today's logic circuits make accurate calculation of the circuit's reliability a very challenging and time-consuming process. This paper introduces a novel, accurate, and efficient algorithm for circuit reliability estimation. The algorithm improves accuracy by taking the effect of reconvergent fan-out nodes into consideration, while improving efficiency by implementing a multithreaded approach for node evaluation. Simulation results show that the proposed algorithm is efficient and more accurate than other reliability estimation algorithms currently proposed in the literature.

Beyond Paralogs: The Multiple Layers of Redundancy in Bacterial Pathogenesis.

Redundancy has been referred to as a state of no longer being needed or useful. Microbiologists often theorize that the only case of true redundancy in a haploid organism would be a recent gene duplication event, prior to divergence through selective pressure. However, a growing number of examples exist where an organism encodes two genes that appear to perform the same function. For example, many pathogens translocate multiple effector proteins into hosts. While disruption of individual effector genes does not result in a discernable phenotype, deleting genes in combination impairs pathogenesis: this has been described as redundancy. In many cases, this apparent redundancy could be due to limitations of laboratory models of pathogenesis that do not fully recapitulate the disease process. Alternatively, it is possible that the selective advantage achieved by this perceived redundancy is too subtle to be measured in the laboratory. Moreover, there are numerous possibilities for different types of redundancy. The most common and recognized form of redundancy is functional redundancy whereby two proteins have similar biochemical activities and substrate specificities allowing each one to compensate in the absence of the other. However, redundancy can also exist between seemingly unrelated proteins that manipulate the same or complementary host cell pathways. In this article, we outline 5 types of redundancy in pathogenesis: molecular, target, pathway, cellular process, and system redundancy that incorporate the biochemical activities, the host target specificities and the impact of effector function on the pathways and cellular process they modulate. For each type of redundancy, we provide examples from Legionella pathogenesis as this organism employs over 300 secreted virulence proteins and loss of individual proteins rarely impacts intracellular growth. We also discuss selective pressures that drive the maintenance of redundant mechanisms, the current methods used to resolve redundancy and features that distinguish between redundant and non-redundant virulence mechanisms.

Children With Dystonia Can Learn a Novel Motor Skill: Strategies That are Tolerant to High Variability.

Children with dystonia are characterized by highly variable and seemingly uncontrolled movements. An important question for any rehabilitative effort is whether these children can learn and improve their performance. This study compared children with dystonia due to cerebral palsy, typically developing children, and healthy adults in their ability to acquire a novel sensorimotor skill. Using a virtual setup, subjects threw a virtual ball tethered to a post to hit a virtual target. Multiple combinations of release angle and velocity of the arm at ball release could achieve a target hit-the task was redundant and afforded solutions with different sensitivity to variability. Subjects performed 200 trials for two target locations that presented different types of redundancy. We hypothesized that children with dystonia develop strategies that are tolerant to their high variability. Estimating this variability highlighted the insufficiency of traditional outcome measures. Therefore, additional analyses of data distributions and of ball release timing were applied. Results showed that: 1) children with dystonia reduced their performance error despite their high variability; 2) this improvement was brought about by finding error-tolerant solutions; and 3) they generated arm trajectories that created time windows for ball release that were tolerant to timing variability. While reduced in magnitude, the performance improvements in children with dystonia paralleled those in healthy children and adults. These findings demonstrate that children with dystonia are able to adapt their behavior to their high variability, an important basis for any rehabilitative intervention.

Robustness to sensor damage of a highly redundant gas sensor array

In this paper we study the role of redundant sensory information to prevent the performance degradation of a chemical sensor array for different distributions of sensor failures across sensor types. The large amount of sensing conditions with two different types of redundancy provided by our sensor array makes possible a comprehensive experimental study. Particularly, our sensor array is composed of 8 different types of commercial MOX sensors modulated in temperature with two redundancy levels: (1) 12 replicates of each sensor type for a total of 96 sensors and (2) measurements using 16 load resistors per sensors for a total of 1536 redundant measures per second. We perform two experiments to determine the performance degradation of the array with increasing number of damaged sensors in two different scenarios of sensor faults distributions across sensor types. In the first experiment, we characterize the diversity and redundancy of the array for increasing number of damaged sensors. To measure diversity and redundancy, we proposed a functional definition based on clustering of sensor features. The second experiment is devoted to determine the performance degradation of the array for the effect of faulty sensors. To this end, the system is trained to separate ethanol, acetone and butanone at different concentrations using a PCA–LDA model. Test set samples are corrupted by means of three different simulated types of faults. To evaluate the performance of the array we used the Fisher score as a measure of odour separability. Our results show that to exploit to the utmost the redundancy of the sensor array faulty sensory units have to be distributed uniformly across the different sensor types.

Robustness to Sensor Damage of a Highly Redundant Gas Sensor Array

Abstract In this paper we study the role of redundant sensory information to prevent the performance degradation of a chemical sensor array as the number of faulty sensors increases. The large amount of sensing conditions with two different types of redundancy provided by our sensor array makes possible a comprehensive experimental study. Particularly, our sensor array is composed of 8 different types of commercial MOX sensors modulated in temperature with two redundancy levels: 1) 12 replicates of each sensor type for a total of 96 sensors, and 2) measurements using 16 load resistors per sensors for a total of 1536 redundant measures per second. The system is trained to identify ethanol, acetone and butanone using a PCA-LDA model. Test set samples are corrupted by means of three different simulated types of faults. To evaluate the tolerance of the array against sensor failure, the Fisher Score is used as a figure of merit for the corrupted test set samples projected on the PCA-LDA model.

The need for the complex use of redundancy to ensure a specified metrological reliability of measurement systems with almost inaccessible components

The problem of ensuring the required level of metrological reliability of measuring systems with almost inaccessible components is considered. The problem of investigations on the use of different types of redundancy to solve this problem is formalized.

REDUNDANCY AND THE JUSTIFICATION FOR FOURTH NORMAL FORM IN RELATIONAL DATABASES

The relationship between the absence of redundancy in relational databases and fourth normal form (4NF) is investigated. A relation scheme is defined to be redundant if there exists a legal relation defined over it which has at least two tuples that are identical on the attributes in a functional dependency (FD) or multivalued dependency (MVD) constraint. Depending on whether the dependencies in a set of constraints or the dependencies in the closure of the set is used, two different types of redundancy are defined. It is shown that the two types of redundancy are equivalent and their absence in a relation scheme is equivalent to the 4NF condition.

Redundancy in Organizational Systems

In this article, I provide a basic introduction to the concepts and theory of redundancy in organizational systems. The roots of redundancy are explored, and four different types of redundancy are identified and discussed. Assumptions underlying both redundant and nonredundant systems are examined. I also review some of the criticisms of redundancy and examine several problems associated with transferring the concepts of redundancy to social systems.

PREDICTION OF THE EFFICIENCY OF PRODUCTION SYSTEMS WITHOUT INTERNAL STORAGE

SUMMARY The efficiency of production systems consisting of a number of interconnected stations can be predicted from the characteristics of the stations when there is no internal storage. Formulae are developed for the efficiency of the basic connections, without and with redundancy. It is shown how the efficiency of more complex systems can be predicted using the basic formulae. The different types of redundancy, parallel, standby and splitting, are compared and it is shown that usually splitting, if feasible, is best. It is indicated how the results can be used to obtain upper and lower bounds on the efficiency with internal storage.