Articles de revues : « String distance measures »

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Winter, Felix, Nysret Musliu et Peter Stuckey. « Explaining Propagators for String Edit Distance Constraints ». Proceedings of the AAAI Conference on Artificial Intelligence 34, n^o 02 (3 avril 2020) : 1676–83. http://dx.doi.org/10.1609/aaai.v34i02.5530.

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The computation of string similarity measures has been thoroughly studied in the scientific literature and has applications in a wide variety of different areas. One of the most widely used measures is the so called string edit distance which captures the number of required edit operations to transform a string into another given string. Although polynomial time algorithms are known for calculating the edit distance between two strings, there also exist NP-hard problems from practical applications like scheduling or computational biology that constrain the minimum edit distance between arrays of decision variables. In this work, we propose a novel global constraint to formulate restrictions on the minimum edit distance for such problems. Furthermore, we describe a propagation algorithm and investigate an explanation strategy for an edit distance constraint propagator that can be incorporated into state of the art lazy clause generation solvers. Experimental results show that the proposed propagator is able to significantly improve the performance of existing exact methods regarding solution quality and computation speed for benchmark problems from the literature.

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ZHANG, LILI, et F. BLANCHET-SADRI. « ALGORITHMS FOR APPROXIMATE K-COVERING OF STRINGS ». International Journal of Foundations of Computer Science 16, n^o 06 (décembre 2005) : 1231–51. http://dx.doi.org/10.1142/s0129054105003789.

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Computing approximate patterns in strings or sequences has important applications in DNA sequence analysis, data compression, musical text analysis, and so on. In this paper, we introduce approximate k-covers and study them under various commonly used distance measures. We propose the following problem: "Given a string x of length n, a set U of m strings of length k, and a distance measure, compute the minimum number t such that U is a set of approximate k-covers for x with distance t". To solve this problem, we present three algorithms with time complexity O(km(n - k)), O(mn2) and O(mn2) under Hamming, Levenshtein and edit distance, respectively. A World Wide Web server interface has been established at for automated use of the programs.

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LYRAS, DIMITRIOS P., KYRIAKOS N. SGARBAS et NIKOLAOS D. FAKOTAKIS. « APPLYING SIMILARITY MEASURES FOR AUTOMATIC LEMMATIZATION : A CASE STUDY FOR MODERN GREEK AND ENGLISH ». International Journal on Artificial Intelligence Tools 17, n^o 05 (octobre 2008) : 1043–64. http://dx.doi.org/10.1142/s021821300800428x.

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This paper addresses the problem of automatic induction of the normalized form (lemma) of regular and mildly irregular words with no direct supervision using language-independent algorithms. More specifically, two string distance metric models (i.e. the Levenshtein Edit Distance algorithm and the Dice Coefficient similarity measure) were employed in order to deal with the automatic word lemmatization task by combining two alignment models based on the string similarity and the most frequent inflectional suffixes. The performance of the proposed model has been evaluated quantitatively and qualitatively. Experiments were performed for the Modern Greek and English languages and the results, which are set within the state-of-the-art, have showed that the proposed model is robust (for a variety of languages) and computationally efficient. The proposed model may be useful as a pre-processing tool to various language engineering and text mining applications such as spell-checkers, electronic dictionaries, morphological analyzers etc.

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ŠIMŮNEK, MARTIN, et BOŘIVOJ MELICHAR. « BORDERS AND FINITE AUTOMATA ». International Journal of Foundations of Computer Science 18, n^o 04 (août 2007) : 859–71. http://dx.doi.org/10.1142/s0129054107005029.

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A border of a string is a prefix of the string that is simultaneously its suffix. It is one of the basic stringology keystones used as a part of many algorithms in pattern matching, molecular biology, computer-assisted music analysis and others. The paper offers the automata-theoretical description of Iliopoulos's ALL_BORDERS algorithm. The algorithm finds all borders of a string with don't care symbols. We show that ALL_BORDERS algorithm is an implementation of a finite state transducer of specific form. We describe how such a transducer can be constructed and what should be the input string like. The described transducer finds a set of lengths of all borders. Last but not least, we define approximate borders and show how to find all approximate borders of a string when we concern Hamming distance definition. Our solution of this problem is based on transducers again. This allows us to use analogy with automata-based pattern matching methods. Finally we discuss conditions under which the same principle can be used for other distance measures.

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Deng, Qiao, Hui Zhang, Jun Li, Xuejun Hou et Hao Wang. « Study of Downhole Shock Loads for Ultra-Deep Well Perforation and Optimization Measures ». Energies 12, n^o 14 (17 juillet 2019) : 2743. http://dx.doi.org/10.3390/en12142743.

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Ultra-deep well perforation is an important direction for the development of unconventional oil and gas resources, the security with shock loads is a difficult technical problem. Firstly, the theoretical analysis of perforated string is carried out, the dynamics models of which are established in the directions of axial, radial and circumferential. Secondly, the process of perforating with hundreds of bullets is simulated by using the software of LS-DYNA (ANSYS, Inc, Pennsylvania, USA). The propagation attenuation model of shock loads is established, and a calculation model to predict shock loads at different positions of the tubing interval has been fitted by considering multiple factors. The dynamic response of perforated string is studied, and the vulnerable parts of which are found out. Thirdly, the optimization measures are put forward for ultra-deep well perforation by the design of shock adsorption and safety distance of the packer. Finally, the field case of an ultra-deep well shows that the research method in this paper is practical, and the optimization measures are reasonable and effective. This study can provide important guidance to reduce shock damage and improve security for ultra-deep well perforation.

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Rowe, Jonathan E. « A Normed Space of Genetic Operators with Applications to Scalability Issues ». Evolutionary Computation 9, n^o 1 (mars 2001) : 25–42. http://dx.doi.org/10.1162/10636560151075103.

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We define an abstract normed vector space where the genetic operators are elements. This is used to define the disturbance of the generational operator g as the distance between the crossover and mutation operator (combined) and the identity. This quantity appears in a bound on the variance of fixed-point populations, and in a bound on the force ‖v – g (v)‖ that applies to the optimal population v. When analyze for the case of fixed-length binary strings, a connection is shown between these measures and the size of the search space. Guides for parameter settings are given, if population convergence is required as the string length tends to infinity.

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Rakhmawati, Nur Aini, et Miftahul Jannah. « Food Ingredients Similarity Based on Conceptual and Textual Similarity ». Halal Research Journal 1, n^o 2 (27 octobre 2021) : 87–95. http://dx.doi.org/10.12962/j22759970.v1i2.107.

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Open Food Facts provides a database of food products such as product names, compositions, and additives, where everyone can contribute to add the data or reuse the existing data. The open food facts data are dirty and needs to be processed before storing the data to our system. To reduce redundancy in food ingredients data, we measure the similarity of ingredient food using two similarities: the conceptual similarity and textual similarity. The conceptual similarity measures the similarity between the two datasets by its word meaning (synonym), while the textual similarity is based on fuzzy string matching, namely Levenshtein distance, Jaro-Winkler distance, and Jaccard distance. Based on our evaluation, the combination of similarity measurements using textual and Wordnet similarity (conceptual) was the most optimal similarity method in food ingredients.

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Zhu, Jin, Dayu Cheng, Weiwei Zhang, Ci Song, Jie Chen et Tao Pei. « A New Approach to Measuring the Similarity of Indoor Semantic Trajectories ». ISPRS International Journal of Geo-Information 10, n^o 2 (20 février 2021) : 90. http://dx.doi.org/10.3390/ijgi10020090.

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People spend more than 80% of their time in indoor spaces, such as shopping malls and office buildings. Indoor trajectories collected by indoor positioning devices, such as WiFi and Bluetooth devices, can reflect human movement behaviors in indoor spaces. Insightful indoor movement patterns can be discovered from indoor trajectories using various clustering methods. These methods are based on a measure that reflects the degree of similarity between indoor trajectories. Researchers have proposed many trajectory similarity measures. However, existing trajectory similarity measures ignore the indoor movement constraints imposed by the indoor space and the characteristics of indoor positioning sensors, which leads to an inaccurate measure of indoor trajectory similarity. Additionally, most of these works focus on the spatial and temporal dimensions of trajectories and pay less attention to indoor semantic information. Integrating indoor semantic information such as the indoor point of interest into the indoor trajectory similarity measurement is beneficial to discovering pedestrians having similar intentions. In this paper, we propose an accurate and reasonable indoor trajectory similarity measure called the indoor semantic trajectory similarity measure (ISTSM), which considers the features of indoor trajectories and indoor semantic information simultaneously. The ISTSM is modified from the edit distance that is a measure of the distance between string sequences. The key component of the ISTSM is an indoor navigation graph that is transformed from an indoor floor plan representing the indoor space for computing accurate indoor walking distances. The indoor walking distances and indoor semantic information are fused into the edit distance seamlessly. The ISTSM is evaluated using a synthetic dataset and real dataset for a shopping mall. The experiment with the synthetic dataset reveals that the ISTSM is more accurate and reasonable than three other popular trajectory similarities, namely the longest common subsequence (LCSS), edit distance on real sequence (EDR), and the multidimensional similarity measure (MSM). The case study of a shopping mall shows that the ISTSM effectively reveals customer movement patterns of indoor customers.

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Jiang, Hao, et Wai Ki Ching. « Physico-Chemically Weighted Kernel for SVM Protein Classification ». Applied Mechanics and Materials 195-196 (août 2012) : 385–90. http://dx.doi.org/10.4028/www.scientific.net/amm.195-196.385.

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In this paper, a novel kernel taking into consideration of the physico-chemical properties of amino acids as well as the motif information is proposed to tackle the problem of protein classification. Similarity matrix is constructed based on an AAindex2 substitution matrix which measures the amino acid pair distance. Together with the motif content posing importance on the protein sequences, a new kernel is constructed. Numerical examples indicate that the string-based kernel in conjunction with SVM classifier performs significantly better than the traditional spectrum kernel method.

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Koehler, Jonathan J., et Caryn A. Conley. « The “Hot Hand” Myth in Professional Basketball ». Journal of Sport and Exercise Psychology 25, n^o 2 (juin 2003) : 253–59. http://dx.doi.org/10.1123/jsep.25.2.253.

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The “hot hand” describes the belief that the performance of an athlete, typically a basketball player, temporarily improves following a string of successes. Although some earlier research failed to detect a hot hand, these studies are often criticized for using inappropriate settings and measures. The present study was designed with these criticisms in mind. It offers new evidence in a unique setting, the NBA Long Distance Shootout contest, using various measures. Traditional sequential dependency runs analyses, individual level analyses, and an analysis of spontaneous outbursts by contest announcers about players who are “on fire” fail to reveal evidence of a hot hand. We conclude that declarations of hotness in basketball are best viewed as historical commentary rather than as prophecy about future performance.

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Zhang, Jifeng, Shoubao Yan, Cheng Jiang, Zhicheng Ji, Chenrun Wang et Weidong Tian. « Network Properties of Cancer Prognostic Gene Signatures in the Human Protein Interactome ». Genes 11, n^o 3 (26 février 2020) : 247. http://dx.doi.org/10.3390/genes11030247.

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Prognostic gene signatures are critical in cancer prognosis assessments and their pinpoint treatments. However, their network properties remain unclear. Here, we obtained nine prognostic gene sets including 1439 prognostic genes of different cancers from related publications. Four network centralities were used to examine the network properties of prognostic genes (PG) compared with other gene sets based on the Human Protein Reference Database (HPRD) and String networks. We also proposed three novel network measures for further investigating the network properties of prognostic gene sets (PGS) besides clustering coefficient. The results showed that PG did not occupy key positions in the human protein interaction network and were more similar to essential genes rather than cancer genes. However, PGS had significantly smaller intra-set distance (IAD) and inter-set distance (IED) in comparison with random sets (p-value < 0.001). Moreover, we also found that PGS tended to be distributed within network modules rather than between modules (p-value < 0.01), and the functional intersection of the modules enriched with PGS was closely related to cancer development and progression. Our research reveals the common network properties of cancer prognostic gene signatures in the human protein interactome. We argue that these are biologically meaningful and useful for understanding their molecular mechanism.

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Wilson, W. C. « Activity Pattern Analysis by Means of Sequence-Alignment Methods ». Environment and Planning A : Economy and Space 30, n^o 6 (juin 1998) : 1017–38. http://dx.doi.org/10.1068/a301017.

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The author describes a method of comparing sequences of characters, called sequence alignment or string matching, and illustrates its use in the analysis of daily activity patterns derived from time-use diaries. It allows definition of measures of similarity or distance between complete sequences, called global alignment, or the evaluation of the best fit of short sequences within long sequences, called local alignment. Alignments may be done pairwise to develop similarity or distance matrices that describe the relatedness of individuals in the set of sequences being examined. Pairwise alignment methods may be extended to many individuals by using multiple alignment analysis. A number of elementary hand-worked examples are provided. The basic concepts are discussed in terms of the problems of time-use research and the method is illustrated by examining diary data from a survey conducted in Reading, England. The CLUSTAL software used for the alignments was written for molecular biological research. The method offers a powerful technique for analyzing the full richness of diary data without discarding the details of episode ordering, duration, or transition. It is also possible to extend the analysis to include the context of activities, such as the presence of other persons or the location, but such extensions would require software designed for social science rather than biochemical problems. The method also offers a challenge to researchers to begin to develop theories about the determinants of daily behavior as a whole, rather than about participation in single activities or about time-budget totals.

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Amlani, Amyn M., et Timothy A. Russo. « Negative Effect of Acoustic Panels on Listening Effort in a Classroom Environment ». Journal of the American Academy of Audiology 27, n^o 10 (novembre 2016) : 805–15. http://dx.doi.org/10.3766/jaaa.15096.

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Background: Acoustic panels are used to lessen the pervasive effects of noise and reverberation on speech understanding in a classroom environment. These panels, however, predominately absorb high-frequency energy important to speech understanding. Therefore, a classroom environment treated with acoustic panels might negatively influence the transmission of the target signal, resulting in an increase in listening effort exerted by the listener. Purpose: Acoustic panels were installed in a public school environment that did not meet the ANSI-recommended guidelines for classroom design. We assessed the modifications to the acoustic climate by quantifying the effect of (1) acoustic panel (i.e., without, with) on the transmission of a standardized target signal at different seat positions (i.e., A–D) using the Speech Transmission Index (STI) and (2) acoustic panel and seat position on listening-effort performance in a group of third-grade students having normal-hearing sensitivity using a dual-task paradigm. Research Design: STI measurements are described qualitatively. We used a repeated-measures randomized design to assess listening-effort performance of monosyllabic words in a primary task and digit recall in a secondary task for the independent variables of acoustic panel and seat position. Study Sample: Twenty-seven, third-grade students (12 males, 15 females), ranging in age from 8.3 to 9.4 yr (mean = 8.7 yr, standard deviation = 0.7), participated in this study. Data Collection and Analysis: Qualitatively, we performed STI measurements under both testing conditions (i.e., panel and seat location). For the primary task of the dual-task paradigm, participants heard a ten-item list of monosyllabic words (i.e., ten words per list) recorded through a manikin in the classroom environment without and with acoustic panels and at different seat positions. Participants were asked to repeat each word exactly as it was heard. During the secondary task, participants were shown a single, random string of five digits before the presentation of the monosyllabic words. After each list in the primary task was completed, participants were asked to recall the string of five digits verbatim. Results: Word-recognition and digit-recall performance decreased with the presence of acoustic panels and as the distance from the target signal to a given seat location increased. The results were validated using the STI, as indicated by a decrease in the transmission of the target signal in the presence of acoustic panel and as the distance to a given seat location increased. Conclusions: The inclusion of acoustic panels reduced the negative effects of noise and reverberation in a classroom environment, resulting in an acoustic climate that complied with the ANSI-recommended guidelines for classroom design. Results, however, revealed that participants required an increased amount of mental effort when the classroom was modified with acoustic treatment compared to no acoustic treatment. Independent of acoustic treatment, mental effort was greatest at seat locations beyond the critical distance (CD). With the addition of acoustic panels, mental effort was found to increase significantly at seat locations beyond the CD compared to the unmodified room condition. Overall, results indicate that increasing the distance between the teacher and child has a detrimental impact on mental effort and, ultimately, academic performance.

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Kerbiriou, Christian, Yves Bas, Isabelle Le Viol, Romain Lorrillière, Justine Mougnot et Jean-François Julien. « Bat Pass Duration Measurement : An Indirect Measure of Distance of Detection ». Diversity 11, n^o 3 (22 mars 2019) : 47. http://dx.doi.org/10.3390/d11030047.

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Few reports have been published on detection distances of bat calls because the evaluation of detection distance is complicated. Several of the approaches used to measure detection distances are based on the researcher’s experience and judgment. More recently, multiple microphones have been used to model flight path. In this study, the validity of a low-cost and simple detectability metric was tested. We hypothesize that the duration of an echolocating-bat-pass within the area of an ultrasonic bat detector is correlated with the distance of detection. Two independent datasets from a large-scale acoustic bat survey—a total of 25,786 bat-passes from 20 taxa (18 species and two genera)—were measured. We found a strong relationship between these measures of bat-pass duration and published detection distances. The advantages of bat-pass duration measures are that, for each study, experimenters easily produce their own proxy for the distance of detection. This indirect measure of the distance of detection could be mobilized to monitor the loss in microphone sensitivity used to monitor long-term population trends. Finally, the possibility of producing an index for distance of detection provides a weight for each bat species’ activity when they are aggregated to produce a bat community metric, such as the widely used “total activity”.

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Nagamotoo, Y., K. Lai et G. Cavell. « Measuring drug name similarity to prioritise the application of tall-man lettering in a computerised pharmacy dispensing system ». International Journal of Pharmacy Practice 30, Supplement_2 (30 novembre 2022) : ii35—ii36. http://dx.doi.org/10.1093/ijpp/riac089.041.

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Abstract Introduction Medicine name similarity is a contributory factor to medication errors.1 Published lists exists highlighting medicine pairs that are easily confused; locally a Look-Alike-Sound-Alike (LASA) list has expanded over time with no formal system of triage. A multipronged approach is required to address LASA risks. Tall-Man Lettering (TML) is one intervention that uses uppercase lettering for the dissimilarities in look-alike drug names to alert staff to the risk of error.1 For greatest impact, it should be reserved for pairs with the highest risk for patient safety. Aim This study aimed to use Levenshtein Distance (LD), Bigram (Bi) and Trigram (Tri) methods to prioritise medicine pairs for TML in the Pharmacy dispensing system. Objectives were to: Produce a comprehensive list of medicines pairs; Establish normalised thresholds from LD, Bi and Tri to prioritise medicine pairs for TML; and, measure drug name similarity using validated software2 applying LD, Bi and Tri to medication pairs as a method of triage for orthographic assessment. Methods Approval was obtained by the Trust Pharmacy Research Committee. The need for ethical submission was waived. A LASA list was developed combining medicine name pairs from National Pharmacy Association list3, historical local list and internal incidents where medicine name confusion was cited. Duplicated, branded and non-stock pairs were excluded. A literature search was undertaken to identify published thresholds for accuracy and sensitivity of the methods in the measure of medicine name similarity. LD measures the minimum number of edit operations needed to transform one string into another; Bi and Tri measures the frequency in which two/three similar sequential strings appear within a medicine name respectively. Two assessors independently entered medicine pairs through a validated computer program2 applying LD, Bi and Tri to measure orthographic similarity. Normalised computed similarity scores (between 0-1 where higher values represent increased drug similarity) were collated on Microsoft excel for comparison against thresholds. Results Two-hundred and twelve medicine pairs were identified for review. The literature defined Bi and Tri thresholds at ≥0.3 and ≥0.1 respectively; in absence of this for LD, in-house thresholds were assessed then defined at ≥0.6. LD identified 84 medicine pairs; Bi identified 144; and Tri identified 158; none were uniquely found by LD, four by Bi and 18 by Tri. A final look-alike list with 82 medicine pairs meeting all three thresholds was identified for TML. Discussion/Conclusion Screening using all three methods led to a 61% reduction in medicines pairs allowing prioritisation of TML as an effective intervention based on look-alike pairs with the highest risk of error. This study focused on identifying orthographic similarity in ‘look-alike’ medicine pairs only. With no single intervention available to prevent LASA errors, future work can explore other interventions. In the absence of literature around normalised LD, the definition of an in-house threshold posed to be another limitation and an area where further exploratory work should be considered. As new LASA incidents arise or the Trust catalogue increases, these methods should be applied to triage their look-alike potential, confirming if TML is an appropriate intervention. References 1. World Health Organisation. Look-alike, sound-alike medication names. patient safety solutions. 2007 May, Volume 1: Solution 1. 2. Strcmp2. [Internet] Department of Computer Science, University of Toronto: Aditya Bhargava [Date of publication unknown]. Available from: https://www.cs.toronto.edu/~aditya/strcmp2/, Work based on: Grzegorz Kondrak. N-gram similarity and distance. Proceedings of the Twelfth International Conference on String Processing and Information Retrieval. 2005 Nov; pp. 115—126. 3. The National Pharmacy Association Pharmacy Team. Look-alike sound-alike (LASA) items [Internet]. The National Pharmacy Association; 2021. Available from: https://www.npa.co.uk/information-and-guidance/look-alike-sound-alike-lasa-items/

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Al-Bakry, Abbas, et Marwa Al-Rikaby. « Enhanced Levenshtein Edit Distance Method functioning as a String-to-String Similarity Measure ». Iraqi Journal for Computers and Informatics 42, n^o 1 (31 décembre 2016) : 48–54. http://dx.doi.org/10.25195/ijci.v42i1.83.

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Levenshtein is a Minimum Edit Distance method; it is usually used in spell checking applications for generatingcandidates. The method computes the number of the required edit operations to transform one string to another and it canrecognize three types of edit operations: deletion, insertion, and substitution of one letter. Damerau modified the Levenshteinmethod to consider another type of edit operations, the transposition of two adjacent letters, in addition to theconsidered three types. However, the modification suffers from the time complexity which was added to the original quadratictime complexity of the original method. In this paper, we proposed a modification for the original Levenshtein toconsider the same four types using very small number of matching operations which resulted in a shorter execution timeand a similarity measure is also achieved to exploit the resulted distance from any Edit Distance method for finding the amountof similarity between two given strings.

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Falkensteiner, Roland, Richard Seeber, Markus Reichhartinger et Martin Horn. « Distance Measures for Strong Observability and Strong Detectability of Systems With Direct Feedthrough ». IEEE Control Systems Letters 5, n^o 2 (avril 2021) : 565–70. http://dx.doi.org/10.1109/lcsys.2020.3004279.

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Mattiussi, Claudio, Markus Waibel et Dario Floreano. « Measures of Diversity for Populations and Distances Between Individuals with Highly Reorganizable Genomes ». Evolutionary Computation 12, n^o 4 (décembre 2004) : 495–515. http://dx.doi.org/10.1162/1063656043138923.

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In this paper we address the problem of defining a measure of diversity for a population of individuals whose genome can be subjected to major reorganizations during the evolutionary process. To this end, we introduce a measure of diversity for populations of strings of variable length defined on a finite alphabet, and from this measure we derive a semi-metric distance between pairs of strings. The definitions are based on counting the number of substrings of the strings, considered first separately and then collectively. This approach is related to the concept of linguistic complexity, whose definition we generalize from single strings to populations. Using the substring count approach we also define a new kind of Tanimoto distance between strings. We show how to extend the approach to representations that are not based on strings and, in particular, to the tree-based representations used in the field of genetic programming. We describe how suffix trees can allow these measures and distances to be implemented with a computational cost that is linear in both space and time relative to the length of the strings and the size of the population. The definitions were devised to assess the diversity of populations having genomes of variable length and variable structure during evolutionary computation runs, but applications in quantitative genomics, proteomics, and pattern recognition can be also envisaged.

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Olson, Jay A., Johnny Nahas, Denis Chmoulevitch, Simon J. Cropper et Margaret E. Webb. « Naming unrelated words predicts creativity ». Proceedings of the National Academy of Sciences 118, n^o 25 (17 juin 2021) : e2022340118. http://dx.doi.org/10.1073/pnas.2022340118.

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Several theories posit that creative people are able to generate more divergent ideas. If this is correct, simply naming unrelated words and then measuring the semantic distance between them could serve as an objective measure of divergent thinking. To test this hypothesis, we asked 8,914 participants to name 10 words that are as different from each other as possible. A computational algorithm then estimated the average semantic distance between the words; related words (e.g., cat and dog) have shorter distances than unrelated ones (e.g., cat and thimble). We predicted that people producing greater semantic distances would also score higher on traditional creativity measures. In Study 1, we found moderate to strong correlations between semantic distance and two widely used creativity measures (the Alternative Uses Task and the Bridge-the-Associative-Gap Task). In Study 2, with participants from 98 countries, semantic distances varied only slightly by basic demographic variables. There was also a positive correlation between semantic distance and performance on a range of problems known to predict creativity. Overall, semantic distance correlated at least as strongly with established creativity measures as those measures did with each other. Naming unrelated words in what we call the Divergent Association Task can thus serve as a brief, reliable, and objective measure of divergent thinking.

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Vale, David S., et Mauro Pereira. « The influence of the impedance function on gravity-based pedestrian accessibility measures : A comparative analysis ». Environment and Planning B : Urban Analytics and City Science 44, n^o 4 (1 avril 2016) : 740–63. http://dx.doi.org/10.1177/0265813516641685.

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Pedestrian accessibility has been growing in importance as an urban planning objective. Assessing it with gravity-based or potential accessibility measures requires the selection of an impedance function in order to reflect the friction of distance. The choice of impedance function is crucial to pedestrian accessibility assessment due to the level of spatial data detail required and also because perceived distances differ from physical distances. Here, we measure and compare 20 gravity-based measures, varying the impedance function and associated parameters. Correlation analysis revealed a significant and strong correlation between the measures. Factor analysis extracted two groups of measures, differing mainly in their maximum cutoff travel distance, i.e. the distance at which the impedance function reaches zero. Spatial analysis revealed that all measures produce similar spatial results in terms of identifying high and low accessibility locations but different values for medium accessibility locations. Places located at between 200 and 400 m from an opportunity are especially sensitive to the impedance function used. We promote a cumulative–Gaussian approach to measure pedestrian accessibility, as it explicitly includes the travel tolerance concept and we found it to be the most robust measure in terms of data variability.

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Awad, Louis N., Darcy S. Reisman et Stuart A. Binder-Macleod. « Do Improvements in Balance Relate to Improvements in Long-Distance Walking Function after Stroke ? » Stroke Research and Treatment 2014 (2014) : 1–6. http://dx.doi.org/10.1155/2014/646230.

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Stroke survivors identify a reduced capacity to walk farther distances as a factor limiting their engagement at home and in community. Previous observational studies have shown that measures of balance ability and balance self-efficacy are strong predictors of long-distance walking function after stroke. Consequently, recommendations to target balance during rehabilitation have been put forth. The purpose of this study was to determine if the changes in balance and long-distance walking function observed following a 12-week poststroke walking rehabilitation program were related. For thirty-one subjects with hemiparesis after stroke, this investigation explored the cross-sectional (i.e., before training) and longitudinal (i.e., changes due to intervention) relationships between measures of standing balance, walking balance, and balance self-efficacy versus long-distance walking function as measured via the 6-minute walk test (6MWT). A regression model containing all three balance variables accounted for 60.8% of the variance in 6MWT performance (R2=.584;F(3,27)=13.931;P<.001); however, only dynamic balance (FGA) was an independent predictor (β=.502) of 6MWT distance. Interestingly, changes in balance were unrelated to changes in the distance walked (each correlation coefficient<.17,P>.05). For persons after stroke similar to those studied, improving balance may not be sufficient to improve long-distance walking function.

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Shin, Jungpil, Md Abdur Rahim et Keun Soo Yun. « Panoramic Image Stitching with Efficient Brightness Fusion Using RANSAC Algorithm ». International Journal of Engineering & ; Technology 7, n^o 3.34 (1 septembre 2018) : 267. http://dx.doi.org/10.14419/ijet.v7i3.34.18981.

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Background/Objectives: Image stitching can enhance the picture very pleasant by modifying and mixing the different aspects.Therefore, we present panoramic image stitching with efficient brightness fusion which is challenging in different bright sequences taken from different angles.Methods/Statistical analysis:For the problem of brightness, the input image is mixed with sequential images in different brightness.In this works, we proposed atechnique that blends multiple brightness using simple quality measures like color, saturation and contrast.The resulting image quality is good, and most important thing is, the method is efficient since it is simple. Thanthe resulting fused images is applied for panorama image stitching. We used multiband blending to prevent the blurring, and BRIEF (binary robust independent elementary features) method for feature descriptors. We solved the multi-image matching problem using Hamming Distanceusing the binary string based descriptors which is most similar features compare with the second most similar images.We proposed FLANN based matcher to get the more accurate results for using large datasets. We estimate Homography with the matching images using RANSAC algorithms.Findings:An effective structure is performed when we are able to resolve the brightness correction in expose too much or expose for too short a time and the appearance ghost. To solve the unification of brightness, we have collected the input images in different exposures, and selection of the good parts of each picture to an input image for stitching.We removed the blurring from input images, and solved multi-image matching using Hamming distance method. We found better results comparing other methods. For large dataset, we used FLANN based matcher, and estimated the Homography using RANSAC algorithm.Improvements/Applications:We have shown the performance of panoramic image stitching with efficient brightness fusion. We performed stitching with high regulationimages. Finally, we were able to create a panoramic image with efficient brightness fusion.

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Nowé, Vicky, Floris L. Wuyts, Mieke Hoppenbrouwers, Paul H. Van de Heyning, Arthur M. De Schepper et Paul M. Parizel. « The interutricular distance determined from external landmarks ». Journal of Vestibular Research 13, n^o 1 (1 septembre 2003) : 17–23. http://dx.doi.org/10.3233/ves-2003-13103.

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Knowledge of the exact distance between the utricles is important in new vestibular tests, such as the unilateral centrifugation (UC) test for the unilateral examination of the utricles. During this test, subjects are rotated at constant velocity and simultaneously laterally displaced along an interaural axis so that one labyrinth becomes aligned with the axis of rotation. When the axis of rotation crosses precisely through one labyrinth, only the opposite labyrinth is stimulated. To achieve this setup, precise knowledge of the interutricular distance is needed. The purpose of this study is to investigate the correlation between the interutricular distance (IUD), measured on T2-weighted magnetic resonance images, and specific external measures of head dimensions such as distance nasion-inion, intermastoid distance (IMD), distances between the temporomandibular joints and between the lateral margins of the orbits. Data have been collected in a series of 50 subjects (25 men and 25 women). On MR images we found a mean IUD of 7.22 cm ( S D = 0.42 cm). There was a strong correlation between the IUD measured on MR images and the intermastoid distance. A linear combination of the IMD, nasion-inion distance and height of the subjects could predict the IUD very satisfactory (R=0.85, adjusted R 2 = 0.723). We also determined a measure of eccentricity of the vestibular labyrinths. The 95% prediction interval for the asymmetry appeared to be less than 4.3%.

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Bastías, Nicolas, et Gonzalo A. Montalva. « Chile Strong Ground Motion Flatfile ». Earthquake Spectra 32, n^o 4 (novembre 2016) : 2549–66. http://dx.doi.org/10.1193/102715eqs158dp.

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The Nazca-South American plate boundary produces large-magnitude events (Mw > 8) every 20 years on the coast of Chile. This work describes a public ground motion database that contains 3,572 records from 477 earthquakes and 181 seismic stations, which includes the recent 2015 Mw 8.3 Illapel earthquake. The data set is controlled by subduction interface and inslab events. The oldest event included is Valparaiso (1985), and the magnitude span is 4.6–8.8 Mw. The source-to-site distance metrics reported are the closest distance to the rupture plane ( R rup), epicentral ( R epi) and hypocentral ( R hyp) distances, with a range for R rup from 20 to 650 km. Site characterization is based on V S30, ranging from 110 to 1,951 m/s. Intensity measures included are peak ground acceleration, spectral acceleration values from 0.01 to 10 s, Arias intensity, and peak ground velocity. Each record was uniformly processed component by component. A flatfile with the related metadata and the spectral accelerations from processed ground motions is available at NEEShub ( http://doi.org/10.17603/DS2N30J ; Bastías and Montalva 2015 ).

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KRÓL, JERZY. « TOPOS THEORY AND SPACETIME STRUCTURE ». International Journal of Geometric Methods in Modern Physics 04, n^o 02 (mars 2007) : 297–303. http://dx.doi.org/10.1142/s0219887807002028.

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According to the recently proposed model of spacetime, various difficulties of quantum field theories and semiclassical quantum gravity on curved 4-Minkowski spacetimes gain new formulations, leading to new solutions. The quantum mechanical effects appear naturally when diffeomorphisms are lifted to 2-morphisms between topoi. The functional measures can be well defined. Diffeomorphisms invariance and background independence are approached from the perspective of topoi. In the spacetimes modified at short distances by the internal structure of some topoi, the higher dimensional regions appear and field/strings duality emerges. We show that the model has natural extensions over extremely strong gravity sources in spacetime and shed light on the strong string coupling definition of B-type D-branes.

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Yang, Jie, Xiaodan Qin, Guoyin Wang, Xiaoxia Zhang et Baoli Wang. « Relative Knowledge Distance Measure of Intuitionistic Fuzzy Concept ». Electronics 11, n^o 20 (19 octobre 2022) : 3373. http://dx.doi.org/10.3390/electronics11203373.

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Knowledge distance is used to measure the difference between granular spaces, which is an uncertainty measure with strong distinguishing ability in a rough set. However, the current knowledge distance failed to take the relative difference between granular spaces into account under the given perspective of uncertain concepts. To solve this problem, this paper studies the relative knowledge distance of intuitionistic fuzzy concept (IFC). Firstly, a micro-knowledge distance (md) based on information entropy is proposed to measure the difference between intuitionistic fuzzy information granules. Then, based on md, a macro-knowledge distance (MD) with strong distinguishing ability is further constructed, and it is revealed the rule that MD is monotonic with the granularity being finer in multi-granularity spaces. Furthermore, the relative MD is further proposed to analyze the relative differences between different granular spaces from multiple perspectives. Finally, the effectiveness of relative MD is verified by relevant experiments. According to these experiments, the relative MD has successfully measured the differences in granular space from multiple perspectives. Compared with other attribute reduction algorithms, the number of subsets after reduction by our algorithm is in the middle, and the mean-square error value is appropriate.

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Jee, Inh, Sherry H. Suyu, Eiichiro Komatsu, Christopher D. Fassnacht, Stefan Hilbert et Léon V. E. Koopmans. « A measurement of the Hubble constant from angular diameter distances to two gravitational lenses ». Science 365, n^o 6458 (12 septembre 2019) : 1134–38. http://dx.doi.org/10.1126/science.aat7371.

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The local expansion rate of the Universe is parametrized by the Hubble constant, H0, the ratio between recession velocity and distance. Different techniques lead to inconsistent estimates of H0. Observations of Type Ia supernovae (SNe) can be used to measure H0, but this requires an external calibrator to convert relative distances to absolute ones. We use the angular diameter distance to strong gravitational lenses as a suitable calibrator, which is only weakly sensitive to cosmological assumptions. We determine the angular diameter distances to two gravitational lenses, 810−130+160 and 1230−150+180 megaparsec, at redshifts z=0.295 and 0.6304. Using these absolute distances to calibrate 740 previously measured relative distances to SNe, we measure the Hubble constant to be H0=82.4−8.3+8.4 kilometers per second per megaparsec.

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ARDILA, YOAN JOSÉ PINZÓN, RAPHAËL CLIFFORD, COSTAS S. ILIOPOULOS, GAD M. LANDAU et MANAL MOHAMED. « NECKLACE SWAP PROBLEM FOR RHYTHMIC SIMILARITY MEASURES ». International Journal of Computational Methods 05, n^o 03 (septembre 2008) : 351–63. http://dx.doi.org/10.1142/s0219876208001583.

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Given two n-bit (cyclic) binary strings, A and B, represented on a circle (necklace instances), let each sequence have the same number (k) of 1's. We are interested in computing the cyclic swap distance between A and B, i.e. the minimum number of swaps needed to convert A to B, minimized over all possible rotations of B. We show that, given the compressed representation of A and B, this distance may be computed in O(k2).

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Hanson, Thor, Steven Brunsfeld, Bryan Finegan et Lisette Waits. « Conventional and genetic measures of seed dispersal for Dipteryx panamensis (Fabaceae) in continuous and fragmented Costa Rican rain forest ». Journal of Tropical Ecology 23, n^o 6 (29 octobre 2007) : 635–42. http://dx.doi.org/10.1017/s0266467407004488.

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The effects of habitat fragmentation on seed dispersal can strongly influence the evolutionary potential of tropical forest plant communities. Few studies have combined traditional methods and molecular tools for the analysis of dispersal in fragmented landscapes. Here seed dispersal distances were documented for the tree Dipteryx panamensis in continuous forest and two forest fragments in Costa Rica, Central America. Distance matrices were calculated between adult trees (n = 283) and the locations of seeds (n = 3016) encountered along 100 × 4-m transects (n = 77). There was no significant difference in the density of seeds dispersed > 25 m from the nearest adult (n = 253) among sites. There was a strong correlation between the locations of dispersed seeds and the locations of overstorey palms favoured as bat feeding roosts in continuous forest and both fragments. Exact dispersal distances were determined for a subset of seeds (n = 14) from which maternal endocarp DNA could be extracted and matched to maternal trees using microsatellite analysis. Dispersal within fragments and from pasture trees into adjacent fragments was documented, at a maximum distance of 853 m. Results show no evidence of a fragmentation effect on D. panamensis seed dispersal in this landscape and strongly suggest bat-mediated dispersal at all sites.

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Zhang, Pengcheng, Yan Xiao, Yuelong Zhu, Jun Feng, Dingsheng Wan, Wenrui Li et Hareton Leung. « A New Symbolization and Distance Measure Based Anomaly Mining Approach for Hydrological Time Series ». International Journal of Web Services Research 13, n^o 3 (juillet 2016) : 26–45. http://dx.doi.org/10.4018/ijwsr.2016070102.

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Most of the time series data mining tasks attempt to discover data patterns that appear frequently. Abnormal data is often ignored as noise. There are some data mining techniques based on time series to extract anomaly. However, most of these techniques cannot suit big unstable data existing in various fields. Their key problems are high fitting error after dimension reduction and low accuracy of mining results. This paper studies an approach of mining time series abnormal patterns in the hydrological field. The authors propose a new idea to solve the problem of hydrological anomaly mining based on time series. They propose Feature Points Symbolic Aggregate Approximation (FP_SAX) to improve the selection of feature points, and then measures the distance of strings by Symbol Distance based Dynamic Time Warping (SD_DTW). Finally, the distances generated are sorted. A set of dedicated experiments are performed to validate the authors' approach. The results show that their approach has lower fitting error and higher accuracy compared to other approaches.

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Houston, Heidi, et Hiroo Kanamori. « Comparison of strong-motion spectra with teleseismic spectra for three magnitude 8 subduction-zone earthquakes ». Bulletin of the Seismological Society of America 80, n^o 4 (1 août 1990) : 913–34. http://dx.doi.org/10.1785/bssa0800040913.

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Abstract We studied strong-motion spectra observed for three Mw 7.8 to 8.0 earthquakes (the 1985 Michoacán, Mexico; 1985 Valparaíso, Chile; and 1983 Akita-Oki, Japan earthquakes). We determined the decay of spectral amplitude with distance from the station, considering different measures of distance from a finite fault. We compared strong-motion spectra (Fourier acceleration spectra) observed for these three earthquakes with those estimated from the source spectrum determined from teleseismic P waves. We scaled the teleseismic source spectra to produce reference strong-motion spectra at periods from 1 to 10 sec using a simple physical model of far-field S body waves from a point source recorded at the surface of a homogeneous half-space. For all three earthquakes the reference spectral amplitudes at periods of 1 to 5 sec are about half the observed ones at distances of about 50 km. The difference increases as the distance increases. At distances of 200 to 300 km, the reference spectrum is about 1/10 of the observed one. The difference between the reference and the observed spectrum is attributed to the contribution of phases other than direct S waves and to site response. We applied corrections for the finiteness (spatial extent) of the source using a simple model of rupture propagation on a dipping two-dimensional fault. Including the source finiteness did not improve the estimate substantially at periods from 1 to 20 sec, but it modeled significant changes in the signal duration as a function of azimuth for the 1985 Michoacán earthquake. Our results can be used to establish empirical relations between the observed spectra and the half-space responses, depending on the distance and the site condition. If such empirical relations can be established, source spectra determined from teleseismic records may be used to estimate strong motions.

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Tanaka, Hisaya, Nobuyuki Sudo et Hideto Ide. « Device Developed to Measure Drive Roller ». Journal of Robotics and Mechatronics 10, n^o 6 (20 décembre 1998) : 533–37. http://dx.doi.org/10.20965/jrm.1998.p0533.

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A new device has been developed to measure the distance from the drive roller to the cage for studying sensor measurement of distance. In one application, it uses a laser, and in another, a strain gauge.

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Shajib, A. J., S. Birrer, T. Treu, A. Agnello, E. J. Buckley-Geer, J. H. H. Chan, L. Christensen et al. « STRIDES : a 3.9 per cent measurement of the Hubble constant from the strong lens system DES J0408−5354 ». Monthly Notices of the Royal Astronomical Society 494, n^o 4 (28 mars 2020) : 6072–102. http://dx.doi.org/10.1093/mnras/staa828.

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ABSTRACT We present a blind time-delay cosmographic analysis for the lens system DES J0408−5354. This system is extraordinary for the presence of two sets of multiple images at different redshifts, which provide the opportunity to obtain more information at the cost of increased modelling complexity with respect to previously analysed systems. We perform detailed modelling of the mass distribution for this lens system using three band Hubble Space Telescope imaging. We combine the measured time delays, line-of-sight central velocity dispersion of the deflector, and statistically constrained external convergence with our lens models to estimate two cosmological distances. We measure the ‘effective’ time-delay distance corresponding to the redshifts of the deflector and the lensed quasar $D_{\Delta t}^{\rm eff}=$$3382_{-115}^{+146}$ Mpc and the angular diameter distance to the deflector Dd = $1711_{-280}^{+376}$ Mpc, with covariance between the two distances. From these constraints on the cosmological distances, we infer the Hubble constant H0= $74.2_{-3.0}^{+2.7}$ km s−1 Mpc−1 assuming a flat ΛCDM cosmology and a uniform prior for Ωm as $\Omega _{\rm m} \sim \mathcal {U}(0.05, 0.5)$. This measurement gives the most precise constraint on H0 to date from a single lens. Our measurement is consistent with that obtained from the previous sample of six lenses analysed by the H0 Lenses in COSMOGRAIL’s Wellspring (H0LiCOW) collaboration. It is also consistent with measurements of H0 based on the local distance ladder, reinforcing the tension with the inference from early Universe probes, for example, with 2.2σ discrepancy from the cosmic microwave background measurement.

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Dutta, Palash. « Medical Diagnosis Based on Distance Measures Between Picture Fuzzy Sets ». International Journal of Fuzzy System Applications 7, n^o 4 (octobre 2018) : 15–36. http://dx.doi.org/10.4018/ijfsa.2018100102.

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This article describes how most frequently uncertainty arises due to vagueness, imprecision, partial information, etc., are encountered in medical diagnosis. To deal with this type of uncertainty, initially fuzzy set theory (FST) was explored and accordingly, medical decision making became one of the most important and interesting areas of applications of FST. Interval valued fuzzy sets (IVFSs) and intuitionistic fuzzy sets (IFS's) were developed and successfully applied in different areas including medical diagnosis. Although, IFS forms a membership degree and a non-membership degree separately in such a way that sum of the two degrees must not exceed one, but one of the important and integral part i.e., degree of neutrality is not taken into consideration in IFS, which is generally occurred in medical diagnosis. In such circumstances, picture fuzzy set (PFS) can be considered as a strong mathematical tool, which adequate in situations when human opinions involved more answers of type: yes, abstain, no. For this purpose, this article, proposes some distance measures on PFS and studies some of its properties. Also, an attempt has been made to carry out medical diagnosis via the proposed distance measures on PFSs and exhibit the technique with a suitable case study. It is found that the distance measures make it possible to introduce weights of all symptoms and consequently patient can be diagnosed directly.

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Kandregula, Parameswara Rao. « Comparison of Apache SOLR Search Spellcheck String Distance Measure – Levenshtein, Jaro Winkler, and N-Gram ». International Journal of Computer Trends and Technology 69, n^o 3 (25 mars 2021) : 1–4. http://dx.doi.org/10.14445/22312803/ijctt-v69i3p101.

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Zhang, Qingyang. « A Class of Association Measures for Categorical Variables Based on Weighted Minkowski Distance ». Entropy 21, n^o 10 (11 octobre 2019) : 990. http://dx.doi.org/10.3390/e21100990.

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Measuring and testing association between categorical variables is one of the long-standing problems in multivariate statistics. In this paper, I define a broad class of association measures for categorical variables based on weighted Minkowski distance. The proposed framework subsumes some important measures including Cramér’s V, distance covariance, total variation distance and a slightly modified mean variance index. In addition, I establish the strong consistency of the defined measures for testing independence in two-way contingency tables, and derive the scaled forms of unweighted measures.

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Cavedo, Federico, Parisa Esmaili et Michele Norgia. « Remote Reflectivity Sensor for Industrial Applications ». Sensors 21, n^o 4 (11 février 2021) : 1301. http://dx.doi.org/10.3390/s21041301.

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A low-cost optical reflectivity sensor is proposed in this paper, able to detect the presence of objects or surface optical properties variations, at a distance of up to 20 m. A collimated laser beam is pulsed at 10 kHz, and a synchronous digital detector coherently measures the back-diffused light collected through a 1-inch biconvex lens. The sensor is a cost-effective solution for punctual measurement of the surface reflection at different distances. To enhance the interference immunity, an algorithm based on a double-side digital baseline restorer is proposed and implemented to accurately detect the amplitude of the reflected light. As results show, the sensor is robust against ambient light and shows a strong sensitivity on a wide reflection range. The capability of the proposed sensor was evaluated experimentally for object detection and recognition, in addition to dedicated measurement systems, like remote encoders or keyphasors, realized far from the object to be measured.

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Hamenstädt, Ursula. « A new description of the Bowen—Margulis measure ». Ergodic Theory and Dynamical Systems 9, n^o 3 (septembre 1989) : 455–64. http://dx.doi.org/10.1017/s0143385700005095.

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AbstractThe Bowen-Margulis measure on the unit tangent bundle of the universal covering of a compact manifold of negative curvature is determined by its restriction to the leaves of the strong unstable foliation. We describe this restriction to any strong unstable manifold W as a spherical measure with respect to a natural distance on W.

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Bilková, Kristína, František Križan, Marcel Horňák, Peter Barlík et Pavol Kita. « Comparing two distance measures in the spatial mapping of food deserts : The case of Petržalka, Slovakia ». Moravian Geographical Reports 25, n^o 2 (1 juin 2017) : 95–103. http://dx.doi.org/10.1515/mgr-2017-0009.

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AbstractOver the last twenty years or so, researchers’ attention to the issue of food deserts has increased in the geographical literature. Accessibility to large-scale retail units is one of the essential and frequently-used indicators leading to the identification and mapping of food deserts. Numerous accessibility measures of various types are available for this purpose. Euclidean distance and street network distance rank among the most frequently-used approaches, although they may lead to slightly different results. The aim of this paper is to compare various approaches to the accessibility to food stores and to assess the differences in the results gained by these methods. Accessibility was measured for residential block centroids, with applications of various accessibility measures in a GIS environment. The results suggest a strong correspondence between Euclidean distance and a little more accurate street network distance approach, applied in the case of the urban environment of Bratislava-Petržalka, Slovakia.

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Luo, Hexian, Qiaoyun Wu et Weijie Pan. « Research and Experiment on Optimal Separation Distance of Adjacent Buildings Based on Performance ». Mathematical Problems in Engineering 2018 (6 septembre 2018) : 1–13. http://dx.doi.org/10.1155/2018/3483401.

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Firstly, constitutive models of two unequal height adjacent ten-story and six-story reinforced concrete frame structures were established based on OpenSees software in which a series of separation distances are set for incremental dynamic analysis (IDA), respectively. Secondly, the seismic vulnerability curves by postprocessing programming in Matlab software were obtained based on IDA datum, and the optimal separation distances of adjacent buildings with and without connecting dampers were obtained by comparing the seismic vulnerability of adjacent building at different separation distance and the seismic hazard analysis. Finally, a scaled model shaking table test of adjacent steel frame structures was performed. The conclusions are obtained by comparing the measured results of the test with those obtained by the OpenSees analysis, such as acceleration and displacement. The conclusions show that when two adjacent buildings are not connected with a damper, the distance of adjacent structures is suggested to be 0.3 m under moderate and strong earthquakes and the distance of adjacent structures is suggested to be a specified value of 0.24 m under rare earthquakes. When two adjacent buildings are connected with dampers, the separation distance is suggested to be 0.1 m under various performance conditions.

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Yang, QinShan, Kuang Qin, Jeff Olson et Marvin Rourke. « Through-Tubing Casing Deformation and Tubing Eccentricity Image Tool for Well-Integrity Monitoring and Plug Abandonment ». Petrophysics – The SPWLA Journal of Formation Evaluation and Reservoir Description 63, n^o 2 (1 avril 2022) : 125–46. http://dx.doi.org/10.30632/pjv63n2-2022a1.

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Casing deformation and tubing eccentricity is a concern in the oil and gas industry for safety and operational reasons. Casing deformation or tubing eccentricity originates from various sources such as well completion, corrosion, formation swelling, collapse, and salt dome creep. It is important to implement a well-integrity surveillance program covering all casing and tubing strings for the full well life cycle from initial completion to abandonment. However, there has been no effective through-tubing logging method to evaluate the casing string for deformation and eccentricity. This paper describes a new Deformation-and-Eccentricity (DEC) tool that is based on electromagnetic technology and designed to measure casing deformation and tubing eccentricity while logging inside completion tubing. The DEC tool generates a unique compressed-and-focused magnetic field that provides an increased signal-to-noise ratio (SNR). The tool then employs an array of magnetic sensors to measure the magnetic flux density distributions azimuthally around the tool. The tool’s compressed-and-focused magnetic field is designed to (1) saturate the magnetic flux of the tubing, (2) to inject more magnetic flux into the first casing behind the tubing, and (3) to increase the signal measurement sensitivity and SNR. The sensor matrix measures flux density changes that correspond to variations in distance between tubing and casing. The high-resolution azimuthal magnetic sensor matrix delivers high-accuracy measurements that are used to image the flux density changes. A finite-element-based forward modeling and an optimized Gaussian processes regression method have been developed to process the raw logging data. The DEC tool has a built-in orientation measurement capability that is based on gyroscopes and accelerometers that are used to align the deformation and eccentricity images and index curves as well as the tubing thickness image. The tool specifications state accuracies of 1% of the eccentricity ratio and 5% of the deformation ratio in the range of casing OD up to 13.375 in. DEC technology provides an advanced answer product for through-tubing casing deformation and eccentricity measurements in downhole well-integrity and plug-abandonment applications. When combined with other well-integrity measurements such as a multifinger caliper and multipipe thickness log tool, a complete well-integrity evaluation can be achieved throughout the life cycle of a well. For example, significant casing deformation can often indicate possible damaged cement behind the casing. Other applications for the technology include locating tubing clamps for fiber-optic cables and control lines and determining the orientation of multistring tubing completions. Performances of the tool have been validated through research simulations, lab tests, and field trials. This paper includes a field case study of a deviated gas production well with tubing buckling and casing micro dogleg.

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Lisi, Matteo P., Marina Scattolin, Martina Fusaro et Salvatore Maria Aglioti. « A Bayesian approach to reveal the key role of mask wearing in modulating projected interpersonal distance during the first COVID-19 outbreak ». PLOS ONE 16, n^o 8 (10 août 2021) : e0255598. http://dx.doi.org/10.1371/journal.pone.0255598.

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Humans typically create and maintain social bonds through interactions that occur at close social distances. The interpersonal distance of at least 1 m recommended as a relevant measure for COVID-19 contagion containment requires a significant change in everyday behavior. In a web-based experimental study conducted during the first pandemic wave (mid-April 2020), we asked 242 participants to regulate their preferred distance towards confederates who did or did not wear protective masks and gloves and whose COVID-19 test results were positive, negative, or unknown. Information concerning dispositional factors (perceived vulnerability to disease, moral attitudes, and prosocial tendencies) and situational factors (perceived severity of the situation in the country, frequency of physical and virtual social contacts, and attitudes toward quarantine) that may modulate compliance with safety prescriptions was also acquired. A Bayesian analysis approach was adopted. Individual differences did not modulate interpersonal distance. We found strong evidence in favor of a reduction of interpersonal distance towards individuals wearing protective equipment and who tested negative to COVID-19. Importantly, shorter interpersonal distances were maintained towards confederates wearing protective gear, even when their COVID-19 test result was unknown or positive. This protective equipment-related regulation of interpersonal distance may reflect an underestimation of perceived vulnerability to infection; this perception must be discouraged when pursuing individual and collective health-safety measures.

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Festing, Michael F. W., et Thomas H. Roderick. « Correlation between genetic distances based on single loci and on skeletal morphology in inbred mice ». Genetical Research 53, n^o 1 (février 1989) : 45–55. http://dx.doi.org/10.1017/s0016672300027853.

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SummaryGenetic and morphometric distances between 12 inbred strains of mice ranging from closely related substrains to a sub-species were estimated using published data on single locus polymorphisms, and on the basis of up to 44 measurements on seven different bones, respectively. Simulation was also used to investigate sampling effects for the single loci. There were strong and statistically highly significant correlations among all measures of genetic distance ranging from 0·58 for the comparison of single loci with the logarithm of the Mahalanobis distance based on 24 measurements on four bones, to 0·72 for estimates of genetic distance based on single loci and the morphology of the mandible. These findings are in sharp contrast with those of Wayne & O'Brien (1986) who claimed that ‘structural gene and morphometric variation of mandible traits are uncoupled between mouse strains’. Their failure to find such a correlation is probably because their sample of inbred strains included only a single pair of closely related substrains, and no substrains separated for less than 40 years, and because they failed to correct for non-linearity between morphometric and single-locus measurement scales. Simulations and regression analysis suggested that genetic distances could be estimated with approximately equal precision using morphological data on bone measurements or about 10 cladistically informative single loci, which would usually involve sampling about 50 loci. Data based on single-gene markers is usually more informative than morphometric data for studying the similarity of independently-derived strains. However, similarities among closely related populations such as sublines of an inbred strain can usually be studied more efficiently using morphometry.

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Shachar, Asaf, et Raz Kupferman. « On strain measures and the geodesic distance to $SO_n$ in the general linear group ». Journal of Geometric Mechanics 8, n^o 4 (novembre 2016) : 437–60. http://dx.doi.org/10.3934/jgm.2016015.

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Fung, Frederick, Chuansi Gao, Lubos Hes et Vladimir Bajzik. « Water vapor resistance measured on sweating thermal manikin and Permetest skin model in the vertical orientation ». Communications in Development and Assembling of Textile Products 1, n^o 1 (15 novembre 2020) : 65–73. http://dx.doi.org/10.25367/cdatp.2020.1.p65-73.

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This paper is a comparison of water vapor resistance (Ret) measured using the Permetest skin model and Tore sweating thermal manikin, i.e. 2D versus 3D methods; and to study the relationship between them. Three materials and five air gap distances were used for the measurement between these two devices, the test conditions in the climatic chambers were set up according to the ISO standard of each measurement method. Results of the correlation coefficient of three materials showed that they all had a strong increasing trend between Permetest and the sweating thermal manikin. From the regression analysis, the P-value of all three materials showed that P< 0.05 and 100% cotton R2=0.83, 50% cotton 50% polyester R2=0.91, 100% polyester R2=0.99. However, Ret resulting values from each device slowed down after 12mm air gap distance.

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Cottereau, Anne-Ségolène, Michel Meignan, Christophe Nioche, Jérôme Clerc, Loic Chartier, Laetitia Vercellino, Olivier Casasnovas, Catherine Thieblemont et Irène Buvat. « New Approaches in Characterization of Lesions Dissemination in DLBCL Patients on Baseline PET/CT ». Cancers 13, n^o 16 (8 août 2021) : 3998. http://dx.doi.org/10.3390/cancers13163998.

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Dissemination, expressed recently by the largest Euclidian distance between lymphoma sites (SDmax), appeared a promising risk factor in DLBCL patients. We investigated alternative distance metrics to characterize the robustness of the dissemination information. In 290 patients from the REMARC trial (NCT01122472), the Euclidean (Euc), Manhattan (Man), and Tchebychev (Tch) distances between the furthest lesions, firstly based on the centroid of each lesion and then directly from the two most distant tumor voxels and the Travelling Salesman Problem distance (TSP) were calculated. For PFS, the areas under the ROC curves were between 0.63 and 0.64, and between 0.62 and 0.65 for OS. Patients with high SDmax whatever the method of calculation or high SD_TSP had a significantly poorer outcome than patients with low SDmax or SD_TSP (p < 0.001 for both PFS and OS), with significance maintained in Ann Arbor advanced-stage patients. In multivariate analysis with total metabolic tumor volume and ECOG, each distance feature had an independent prognostic value for PFS. For OS, only SDmax_Tch, SDmax_Euc _Vox, and SDmax_Man _Vox reached significance. The spread of DLBCL lesions measured by the largest distance between lymphoma sites is a strong independent prognostic factor and could be measured directly from tumor voxels, allowing its development in the area of the deep learning segmentation methods.

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Vershynina, Anna. « Quantum coherence, discord and correlation measures based on Tsallis relative entropy ». Quantum Information and Computation 20, n^o 7&8 (juin 2020) : 553–69. http://dx.doi.org/10.26421/qic20.7-8-2.

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Several ways have been proposed in the literature to define a coherence measure based on Tsallis relative entropy. One of them is defined as a distance between a state and a set of incoherent states with Tsallis relative entropy taken as a distance measure. Unfortunately, this measure does not satisfy the required strong monotonicity, but a modification of this coherence has been proposed that does. We introduce three new Tsallis coherence measures coming from a more general definition that also satisfy the strong monotonicity, and compare all five definitions between each other. Using three coherence measures that we discuss, one can also define a discord. Two of these have been used in the literature, and another one is new. We also discuss two correlation measures based on Tsallis relative entropy. We provide explicit expressions for all three discord and two correlation measure on pure states. Lastly, we provide tight upper and lower bounds on two discord and correlations measures on any quantum state, with the condition for equality.

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Przystańska, Agnieszka, Tomasz Kulczyk, Artur Rewekant, Alicja Sroka, Katarzyna Jończyk-Potoczna, Krzysztof Gawriołek et Agata Czajka-Jakubowska. « The Association between Maxillary Sinus Dimensions and Midface Parameters during Human Postnatal Growth ». BioMed Research International 2018 (2018) : 1–10. http://dx.doi.org/10.1155/2018/6391465.

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Objective. The aim of the study based on CT images was to assess the age-related changes in maxillary sinus diameters in relation to diameters of the facial skeleton. Materials and Methods. The retrospective analysis of CT images of the head of 170 patients aged 0–18 years (85 females and 85 males) was performed. Specific orientation points (zy, zm, pr, ns, n, and P) were identified in every patient and the following distances were measured: zy-zy, maximum facial width; zm-zm, midfacial width; n-pr, upper facial height; ns-pr, alveolar facial height; and ns-P, distance not indicated in craniometry. Results. The maxillary sinuses of every patient were bilaterally measured in three planes. Three diameters were obtained: maximum transverse (horizontal) diameter called MSW, maximum vertical diameter called MSH, and maximum anteroposterior diameter (length) called MSL. In females, the correlation of MSW, MSH, and MSL and zy-zy, as well as n-pr distances, is very strong. Moreover, the significant correlation was found between all measurements of maxillary sinus and ns-pr as well as ns-P distances in females. The correlation between MSL and all measurements of midface as well as MSH and MSW and all measurements except ns-P is stronger in females than in males. In males, all measurements of maxillary sinus correlate with ns-P distance very strongly. Conclusions. The statistical analysis (correlation and determination coefficient) showed that all measurements of maxillary sinuses correlate with midface dimensions.

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Teramoto, Atsushi, Yasutaka Murahashi, Hiroaki Shoji, Tomoaki Kamiya, Kota Watanabe et Toshihiko Yamashita. « Quantitative Evaluation of Ankle Instability Using a Capacitance-Type Strain Sensor ». Foot & ; Ankle Orthopaedics 7, n^o 1 (janvier 2022) : 2473011421S0047. http://dx.doi.org/10.1177/2473011421s00471.

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Category: Basic Sciences/Biologics; Ankle; Sports Introduction/Purpose: Manual evaluation is an important method for assessing ankle instability, but it is not quantitative. Capacitance-type sensors can be used to measure the distance on the basis of the capacitance value. We applied the sensor to the noninvasive device for measuring ankle instability and showed its utility. Methods: First, five ankles embalmed by Thiel's method were used in an experiment using a cadaver. The capacitance-type sensor was fixed alongside the anterior talofibular ligament (ATFL) of a specially made brace, and the anterior drawer test was performed. The test had been performed for the intact ankle, with the ATFL transected, and with both the ATFL and calcaneofibular ligament (CFL) transected. The anterior drawer distance was calculated by the sensor. Intra and interinvestigator reliability were also analyzed. Next, as a clinical study, a brace with a sensor was fitted to 22 ankles of 20 patients with a history of ankle sprain. An anterior drawer test at a load of 150 N was conducted using a Telos stress device. The anterior drawer distances measured by the sensor and based on X-ray images were then compared. Results: The mean anterior drawer distance for the intact cadavers was 3.7 +- 1.0 mm, 6.1 +- 1.6 mm with the ATFL transected (P < 0.001), and 7.9 +- 1.8 mm with the ATFL and CFL transected (P < 0.001). The intrainvestigator intraclass correlation coefficients (ICC) were 0.862-0.939, and the interinvestigator ICC was 0.815. In the experiments on patients, the mean anterior drawer distance measured by the sensor was 2.9 +- 0.9 mm and 2.7 +- 0.9 mm from the X-ray images. The correlation coefficient between the sensor and the X-ray images was 0.843. Conclusion: We carried out a quantitative evaluation of anterior drawer laxity using a capacitance-type sensor and found it had high reproducibility. It was also very strongly correlated with stress radiography measurements in patients with ankle instability. Capacitance-type sensors can be used for the safe, simple, and accurate evaluation of ankle instability.

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Wagner, Jenny, et Sven Meyer. « Generalized model-independent characterization of strong gravitational lenses V : reconstructing the lensing distance ratio by supernovae for a general Friedmann universe ». Monthly Notices of the Royal Astronomical Society 490, n^o 2 (30 septembre 2019) : 1913–27. http://dx.doi.org/10.1093/mnras/stz2717.

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ABSTRACT We determine the cosmic expansion rate from supernovae of type Ia to set up a data-based distance measure that does not make assumptions about the constituents of the universe, i.e. about a specific parametrization of a Friedmann cosmological model. The scale, determined by the Hubble constant H0, is the only free cosmological parameter left in the gravitational lensing formalism. We investigate to which accuracy and precision the lensing distance ratio D is determined from the Pantheon sample. Inserting D and its uncertainty into the lensing equations for given H0, especially the time-delay equation between a pair of multiple images, allows to determine lens properties, especially differences in the lensing potential (Δϕ), without specifying a cosmological model. We expand the luminosity distances into an analytic orthonormal basis, determine the maximum-likelihood weights for the basis functions by a globally optimal χ2-parameter estimation, and derive confidence bounds by Monte Carlo simulations. For typical strong lensing configurations between z = 0.5 and 1.0, Δϕ can be determined with a relative imprecision of 1.7 per cent, assuming imprecisions of the time delay and the redshift of the lens on the order of 1 per cent. With only a small, tolerable loss in precision, the model-independent lens characterisation developed in this paper series can be generalised by dropping the specific Friedmann model to determine D in favour of a data-based distance ratio. Moreover, for any astrophysical application, the approach presented here, provides distance measures for z ≤ 2.3 that are valid in any homogeneous, isotropic universe with general relativity as theory of gravity.

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