Relevant bibliographies by topics / GTH algorithm / Journal articles
To see the other types of publications on this topic, follow the link: GTH algorithm.

Journal articles on the topic 'GTH algorithm'

Author: Grafiati
Published: 10 March 2023

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 journal articles for your research on the topic 'GTH algorithm.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

Cohen, David M., Daniel P. Heyman, Asya Rabinovitch, and Danit Brown. "A Parallel Implementation of the GTH Algorithm." INFORMS Journal on Computing 9, no. 2 (May 1997): 218–23. http://dx.doi.org/10.1287/ijoc.9.2.218.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Seneta, E. "Complementation in Stochastic Matrices and the GTH Algorithm." SIAM Journal on Matrix Analysis and Applications 19, no. 2 (April 1998): 556–63. http://dx.doi.org/10.1137/s0895479896310172.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

O'Cinneide, Colm Art. "Relative-error bounds for the LU decomposition via the GTH algorithm." Numerische Mathematik 73, no. 4 (June 1, 1996): 507–19. http://dx.doi.org/10.1007/s002110050203.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Hong, Sung-Chul, and Soohan Ahn. "Application of GTH-like algorithm to Markov modulated Brownian motion with jumps." Communications for Statistical Applications and Methods 28, no. 5 (September 30, 2021): 477–91. http://dx.doi.org/10.29220/csam.2021.28.5.477.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

O’Leary, Dianne P., and Yuan-Jye Jason Wu. "A Block-GTH Algorithm for Finding the Stationary Vector of a Markov Chain." SIAM Journal on Matrix Analysis and Applications 17, no. 3 (July 1996): 470–88. http://dx.doi.org/10.1137/s0895479894262534.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Azaroual, Meryeme, Mohammed Ouassaid, and Mohamed Maaroufi. "Optimum Energy Flow Management of a Grid-Tied Photovoltaic-Wind-Battery System considering Cost, Reliability, and CO2 Emission." International Journal of Photoenergy 2021 (September 24, 2021): 1–20. http://dx.doi.org/10.1155/2021/5591456.

Full text
Abstract:
The main goal of this paper is to explore the performance of a residential grid-tied hybrid (GTH) system which relies on economic and environmental aspects. A photovoltaic- (PV-) wind turbine- (WT-) battery storage system with maximizing self-consumption and time-of-use (ToU) pricing is conducted to examine the system efficiency. In so doing, technical optimization criteria with taking into consideration renewable energy benefits including feed-in-tariff (FIT) and greenhouse gas emission (GHG) reduction are analyzed. As the battery has a substantial effect on the operational cost of the system, the energy management strategy (EMS) will incorporate the daily operating cost of the battery and the effect of the degradation. The model can give the opportunity to the network to sell or purchase energy from the system. The simulation results demonstrate the effectiveness of the proposed approach in which the new objective function achieves the maximum cost-saving (99.81%) and income (5.16 $/day) compared to other existing strategies as well as the lowest GHG emission. Furthermore, the battery enhances the best daily self-consumption and load cover ratio. Then, as the model is nonlinear, a comparison with other existing algorithms is performed to select the feasible, robust, and reliable model for the residential application. A hybrid algorithm (HGAFMINCON) is developed to demonstrate the superiority of the algorithm over FMINCON and GA shown in terms of cost savings and income.
APA, Harvard, Vancouver, ISO, and other styles
7

Linnemann, Birgit, Rupert Bauersachs, Hannelore Rott, Susan Halimeh, Rainer Zotz, Andrea Gerhardt, Barbara Boddenberg-Pätzold, Bettina Toth, and Ute Scholz. "Diagnosis of pregnancy-associated venous thromboembolism - position paper of the Working Group in Women’s Health of the Society of Thrombosis and Haemostasis (GTH)." Vasa 45, no. 2 (April 2016): 87–101. http://dx.doi.org/10.1024/0301-1526/a000503.

Full text
Abstract:
Abstract. Pregnancy and the postpartum period are associated with an increased risk of venous thromboembolism (VTE). Over the past decade, new diagnostic algorithms have been established, combining clinical probability, laboratory testing and imaging studies for the diagnosis of deep vein thrombosis (DVT) and pulmonary embolism (PE) in the non-pregnant population. However, there is no such generally accepted algorithm for the diagnosis of pregnancy-associated VTE. Studies establishing clinical prediction rules have excluded pregnant women, and prediction scores currently in use have not been prospectively validated in pregnancy or during the postpartum period. D-dimers physiologically increase throughout pregnancy and peak at delivery, so a negative D-dimer test result, based on the reference values of non-pregnant subjects, becomes unlikely in the second and third trimesters. Imaging studies therefore play a major role in confirming suspected DVT or PE in pregnant women. Major concerns have been raised against radiologic imaging because of foetal radiation exposure, and doubts about the diagnostic value of ultrasound techniques in attempting to exclude isolated iliac vein thrombosis grow stronger as pregnancy progresses. As members of the Working Group in Women’s Health of the Society of Thrombosis and Haemostasis (GTH), we summarise evidence from the available literature and aim to establish a more uniform strategy for diagnosing pregnancy-associated VTE.
APA, Harvard, Vancouver, ISO, and other styles
8

Makarevich, N. А. "Thermodynamics of real polymer solutions in the new Rényi and Tsallis formalism." Proceedings of the National Academy of Sciences of Belarus, Chemical Series 57, no. 2 (June 3, 2021): 162–76. http://dx.doi.org/10.29235/1561-8331-2021-57-2-162-176.

Full text
Abstract:
The generalized non-ideality factor of systems (GNF) was introduced into the Renyi and Tsallis information entropy equations, and new expressions were obtained for information and thermodynamic entropies with a fractional moment of the order entropy gS and thermodynamic gth nonideality factors. Equations in formalism of Renyi and Tsallis: The equations describe self-organized structures of essentially non-equilibrium systems and can be used in studying the topological and conformational properties of solutions of high-molecular compounds. GNF: where is are relative average characteristics (pi are statistical probabilities) of opposite processes. Factor g varies in the range 0 ≤ g ≤ 2 and depends on which of the competitive processes prevails. An algorithm for calculating the thermodynamic functions of the state of the system under study is presented. The equations are intended for calculating the thermodynamic functions of objects of fractal nature, including real solutions of synthetic and natural highmolecular compounds of plant and animal origin (hyper branched structures, dendrimers, lignins, biological systems, dendrites, systems of internal organs, blood vessels, etc.).
APA, Harvard, Vancouver, ISO, and other styles
9

Zhang, Jianxun, Quan Zhu, and Jun Li. "Multiple Pathways for Dissociative Adsorption of SiCl4 on the Si(100)-c(4×2) Surface." Symmetry 15, no. 1 (January 11, 2023): 213. http://dx.doi.org/10.3390/sym15010213.

Full text
Abstract:
The adsorption of silicon tetrachloride (STC, SiCl4) on the silicon surface is a crucial process in polysilicon manufacture. However, the underlying mechanism for the adsorption remains highly uncertain. Here, new dissociative adsorption (DA) reaction pathways involving a flip of a silicon dimer in the first layer and considering physisorption are identified. Different DA patterns, inter-row (IR), inter-dimer (ID), and on-dimer (OD), are confirmed by the density functional theory (DFT) calculations at the PBE-D3(BJ)/TZVP-MOLOPT-GTH level. The stable structures for all minima are searched by global optimization through the artificial bee colony (ABC) algorithm. Findings reveal that the parent molecules dissociate first by breaking one Si-Cl bond, following which the resulting SiCl3 and Cl fragments are attached to adjacent Si-atom sites. Moreover, dimer flipping significantly reduces the energy barrier for chemisorption, mainly due to the change in electronic structure that enhances the interaction of the site with the SiCl3 radical. Physisorption may also be accompanied by dimer flipping to form a stable adsorption structure.
APA, Harvard, Vancouver, ISO, and other styles
10

Kirschner, Martin, Nicole do Ó Hartmann, Stefani Parmentier, Christina Hart, Larissa Henze, Guido Bisping, Martin Griesshammer, et al. "Primary Thromboprophylaxis in Patients with Malignancies: Daily Practice Recommendations by the Hemostasis Working Party of the German Society of Hematology and Medical Oncology (DGHO), the Society of Thrombosis and Hemostasis Research (GTH), and the Austrian Society of Hematology and Oncology (ÖGHO)." Cancers 13, no. 12 (June 10, 2021): 2905. http://dx.doi.org/10.3390/cancers13122905.

Full text
Abstract:
Patients with cancer, both hematologic and solid malignancies, are at increased risk for thrombosis and thromboembolism. In addition to general risk factors such as immobility and major surgery, shared by non-cancer patients, cancer patients are exposed to specific thrombotic risk factors. These include, among other factors, cancer-induced hypercoagulation, and chemotherapy-mediated endothelial dysfunction as well as tumor-cell-derived microparticles. After an episode of thrombosis in a cancer patient, secondary thromboprophylaxis to prevent recurrent thromboembolism has long been established and is typically continued as long as the cancer is active or actively treated. On the other hand, primary prophylaxis, even though firmly established in hospitalized cancer patients, has only recently been studied in ambulatory patients. This recent change is mostly due to the emergence of direct oral anticoagulants (DOACs). DOACs have a shorter half-life than vitamin K antagonists (VKA), and they overcome the need for parenteral application, the latter of which is associated with low-molecular-weight heparins (LMWH) and can be difficult for the patient to endure in the long term. Here, first, we discuss the clinical trials of primary thromboprophylaxis in the population of cancer patients in general, including the use of VKA, LMWH, and DOACs, and the potential drug interactions with pre-existing medications that need to be taken into account. Second, we focus on special situations in cancer patients where primary prophylactic anticoagulation should be considered, including myeloma, major surgery, indwelling catheters, or immobilization, concomitant diseases such as renal insufficiency, liver disease, or thrombophilia, as well as situations with a high bleeding risk, particularly thrombocytopenia, and specific drugs that may require primary thromboprophylaxis. We provide a novel algorithm intended to aid specialists but also family practitioners and nurses who care for cancer patients in the decision process of primary thromboprophylaxis in the individual patient.
APA, Harvard, Vancouver, ISO, and other styles
11

Liu, Hsiang Chuan, Yen Kuei Yu, Jeng Ming Yih, and Chin Chun Chen. "Identifying the Mastery Concepts in Linear Algebra by Using FCM-CM Algorithm." Applied Mechanics and Materials 44-47 (December 2010): 3897–901. http://dx.doi.org/10.4028/www.scientific.net/amm.44-47.3897.

Full text
Abstract:
Euclidean distance function based fuzzy clustering algorithms can only be used to detect spherical structural clusters. Gustafson-Kessel (GK) clustering algorithm and Gath-Geva (GG) clustering algorithm were developed to detect non-spherical structural clusters by employing Mahalanobis distance in objective function, however, both of them need to add some constrains for Mahalanobis distance. In this paper, the authors’ improved Fuzzy C-Means algorithm based on common Mahalanobis distance (FCM-CM) is used to identify the mastery concepts in linear algebra, for comparing the performances with other four partition algorithms; FCM-M, GG, GK, and FCM. The result shows that FCM-CM has better performance than others.
APA, Harvard, Vancouver, ISO, and other styles
12

Ben, Mirian Dal, Maura Oliveira, Paola Cappellano, Jorge Sampaio, and Maria Beatriz Dias. "Evaluating the Cost-Effectiveness of Proposed Algorithms for C. difficile Infection in Different Pretest Probability Settings." Infection Control & Hospital Epidemiology 41, S1 (October 2020): s224—s225. http://dx.doi.org/10.1017/ice.2020.769.

Full text
Abstract:
Background: The use of real-time polymerase chain reaction (RT-PCR) as a first-line test for the diagnosis of Clostridioides difficile may result in overdiagnosis and overtreatment because the test is not capable of distinguishing infection from carriage. Toxin EIA assays have impeditive low sensitivity. Some algorithms using enzyme immunoassay for glutamate dehydrogenase (GDH) antigen and toxins A and B as the first step have been proposed to increase diagnostic performance. However, cost-effectiveness of different diagnostic algorithms would depend on the cost of each test and on the pretest probability in different settings. The objective of the present study was to evaluate the cost-effectiveness of 2 algorithms proposed by current guidelines to diagnose C. difficile infection by developing a mathematical model that would take into account the epidemiology and costs in our hospital. Methods: The study was conducted in a 480-bed tertiary-care teaching hospital in So Paulo, Brazil. All suspected C. difficile infection cases from January to December of 2017 were evaluated for pretest probability analysis. All stools collected from patients with a requested PCR test for suspected C. difficile infection were selected for additional testing to measure the specificity and sensitivity of each different test: C. diff GDH/Toxin A/B combined test, Toxin A/B Microplate Assay, GDH, and PCR. Toxigenic stool culture for C. difficile was considered the gold standard. A mathematical model was developed and simulations were done. The outcomes evaluated were: final annual costs with diagnostic tests in US dollars and number of patients receiving a false-positive or a false-negative diagnosis in a year simulation. Results: In total, 1,441 stool samples were tested by PCR for C. difficile in our institution from January 2017 to December 2017. Overall, 206 had a positive result, with a pretest probability of 14.3%. In our simulations, the PCR-based algorithm had an annual cost of US$279,914.25, with 4 false-negative results and 8 false-positive results. The implementation of a GDH/Toxin/PCR stepwise algorithm would have reduced the annual cost to US$160,488.75, with 6 false-negative results and 1 false-positive result. Simulations of annual cost and performance of the 2 algorithms have shown that the stepwise algorithm would still be advantageous in settings with higher pretest probabilities (Fig. 1). Conclusions: A stepwise algorithm based on GDH/Toxin before PCR seems to be more cost-effective, even in settings with higher pretest probabilities.Funding: NoneDisclosures: None
APA, Harvard, Vancouver, ISO, and other styles
13

Li, Xiujuan, Yongxin Liu, Pingping Huang, Xiaolong Liu, Weixian Tan, Wenxue Fu, and Chunming Li. "A Hybrid Polarimetric Target Decomposition Algorithm with Adaptive Volume Scattering Model." Remote Sensing 14, no. 10 (May 19, 2022): 2441. http://dx.doi.org/10.3390/rs14102441.

Full text
Abstract:
Previous studies have shown that scattering mechanism ambiguity and negative power issues still exist in model-based polarization target decomposition algorithms, even though deorientation processing is implemented. One possible reason for this is that the dynamic range of the model itself is limited and cannot fully satisfy the mixed scenario. To address these problems, we propose a hybrid polarimetric target decomposition algorithm (GRH) with a generalized volume scattering model (GVSM) and a random particle cloud volume scattering model (RPCM). The adaptive volume scattering model used in GRH incorporates GVSM and RPCM to model the volume scattering component of the regions dominated by double-bounce scattering and the surface scattering, respectively, to expand the dynamic range of the model. In addition, GRH selects the volume scattering component between GVSM and RPCM adaptively according to the target dominant scattering mechanism of fully polarimetric synthetic aperture radar (PolSAR) data. The effectiveness of the proposed method was demonstrated using AirSAR dataset from San Francisco. Comparison studies were carried out to test the performance of GRH over several target decomposition algorithms. Experimental results show that the GRH outperforms the algorithms we tested in this study in decomposition accuracy and reduces the number of negative power pixels, demonstrating that the GRH can significantly avoid mechanism ambiguity and negative power issues.
APA, Harvard, Vancouver, ISO, and other styles
14

Xu, Changqing, Jiahao Ning, Yi Liu, Mintao Luo, Dongdong Chen, Xiaoling Lin, and Yintang Yang. "Optimization Strategy of Regular NoC Mapping Using Genetic-Based Hyper-Heuristic Algorithm." Symmetry 14, no. 8 (August 9, 2022): 1637. http://dx.doi.org/10.3390/sym14081637.

Full text
Abstract:
Mapping optimization of network-on-chips (NoCs) for specific applications has become one of the most important keys of the SoC top-level design. However, the topology of NoC applied is usually regular topology, such as mesh, torus, etc., which may generate a large number of isomorphic solutions during the process of NoC mapping, which may reduce the convergence speed of mapping algorithms. In this paper, we proposed a generic-based hyper-heuristic algorithm named IRC-GHH for NoC mapping. To reduce the influence of isomorphic solutions, we analyzed the symmetry of NoC topology and proposed crossover operators based on the isomorphic solution to optimize the algorithm. We studied the situation of invalid crossovers and eliminated invalid iterations by adopting an isomorphic replacement crossover (IRC) strategy. To prevent the algorithm from falling into evolutionary stagnation in the late iteration, we introduce an adaptive mechanism to increase the usage frequency of the IRC operator automatically. Compared with GHH without IRC, the GHH with IRC can achieve, on average 15.25% communication energy reduction and 7.84% communication delay reduction.
APA, Harvard, Vancouver, ISO, and other styles
15

Nasser Lauar, Sami, and Mario Mestria. "Greedy Genetic Algorithm for the Data Aggregator Positioning Problem in Smart Grids." Inteligencia Artificial 24, no. 68 (December 21, 2021): 123–37. http://dx.doi.org/10.4114/intartif.vol24iss68pp123-137.

Full text
Abstract:
In this work, we present a metaheuristic based on the genetic and greedy algorithms to solve an application of the set covering problem (SCP), the data aggregator positioning in smart grids. The GGH (Greedy Genetic Hybrid) is structured as a genetic algorithm, but it has many modifications compared to the classic version. At the mutation step, only columns included in the solution can suffer mutation and be removed. At the recombination step, only columns from the parent’s solutions are available to generate the offspring. Moreover, the greedy algorithm generates the initial population, reconstructs solutions after mutation, and generates new solutions from the recombination step. Computational results using OR-Library problems showed that the GGH reached optimal solutions for 40 instances in a total of 75 and, in the other instances, obtained good and promising values, presenting a medium gap of 1,761%.
APA, Harvard, Vancouver, ISO, and other styles
16

Arora, Manuel, Gábor Ivanyos, Marek Karpinski, and Nitin Saxena. "Deterministic polynomial factoring and association schemes." LMS Journal of Computation and Mathematics 17, no. 1 (2014): 123–40. http://dx.doi.org/10.1112/s1461157013000296.

Full text
Abstract:
AbstractThe problem of finding a nontrivial factor of a polynomial$f(x)$over a finite field${\mathbb{F}}_q$has many known efficient, but randomized, algorithms. The deterministic complexity of this problem is a famous open question even assuming the generalized Riemann hypothesis (GRH). In this work we improve the state of the art by focusing on prime degree polynomials; let$n$be the degree. If$(n-1)$has a ‘large’$r$-smooth divisor$s$, then we find a nontrivial factor of$f(x)$in deterministic$\mbox{poly}(n^r,\log q)$time, assuming GRH and that$s=\Omega (\sqrt{n/2^r})$. Thus, for$r=O(1)$our algorithm is polynomial time. Further, for$r=\Omega (\log \log n)$there are infinitely many prime degrees$n$for which our algorithm is applicable and better than the best known, assuming GRH. Our methods build on the algebraic-combinatorial framework of$m$-schemes initiated by Ivanyos, Karpinski and Saxena (ISSAC 2009). We show that the$m$-scheme on$n$points, implicitly appearing in our factoring algorithm, has an exceptional structure, leading us to the improved time complexity. Our structure theorem proves the existence of small intersection numbers in any association scheme that has many relations, and roughly equal valencies and indistinguishing numbers.
APA, Harvard, Vancouver, ISO, and other styles
17

Peiqin, Li, Xie Jianbin, Liu Tong, and Yan Wei. "Finger vein recognition algorithm based on optimized GHT." Optik 125, no. 6 (March 2014): 1780–83. http://dx.doi.org/10.1016/j.ijleo.2013.09.038.

Full text
APA, Harvard, Vancouver, ISO, and other styles
18

Sokouti, Massoud, Ali Zakerolhosseini, and Babak Sokouti. "Medical Image Encryption: An Application for Improved Padding Based GGH Encryption Algorithm." Open Medical Informatics Journal 10, no. 1 (October 28, 2016): 11–22. http://dx.doi.org/10.2174/1874431101610010011.

Full text
Abstract:
Medical images are regarded as important and sensitive data in the medical informatics systems. For transferring medical images over an insecure network, developing a secure encryption algorithm is necessary. Among the three main properties of security services (i.e., confidentiality, integrity, and availability), the confidentiality is the most essential feature for exchanging medical images among physicians. The Goldreich Goldwasser Halevi (GGH) algorithm can be a good choice for encrypting medical images as both the algorithm and sensitive data are represented by numeric matrices. Additionally, the GGH algorithm does not increase the size of the image and hence, its complexity will remain as simple as O(n2). However, one of the disadvantages of using the GGH algorithm is the Chosen Cipher Text attack. In our strategy, this shortcoming of GGH algorithm has been taken in to consideration and has been improved by applying the padding (i.e., snail tour XORing), before the GGH encryption process. For evaluating their performances, three measurement criteria are considered including(i)Number of Pixels Change Rate (NPCR),(ii)Unified Average Changing Intensity (UACI), and(iii)Avalanche effect. The results on three different sizes of images showed that padding GGH approach has improved UACI, NPCR, and Avalanche by almost 100%, 35%, and 45%, respectively, in comparison to the standard GGH algorithm. Also, the outcomes will make the padding GGH resist against the cipher text, the chosen cipher text, and the statistical attacks. Furthermore, increasing the avalanche effect of more than 50% is a promising achievement in comparison to the increased complexities of the proposed method in terms of encryption and decryption processes.
APA, Harvard, Vancouver, ISO, and other styles
19

Perry, Michael, Lee Graham, Sweta Parida, Phoebe Katzenbach, Jose Luis Baptista Baeza, Joel Estis, Johanna Sandlund, et al. "2357. Toxin Detection Using Single Molecule Counting Technology: The Best of Both Worlds?" Open Forum Infectious Diseases 6, Supplement_2 (October 2019): S812. http://dx.doi.org/10.1093/ofid/ofz360.2035.

Full text
Abstract:
Abstract Background Accurate diagnosis of CDI remains challenging as there is no standalone laboratory test with adequate clinical sensitivity and specificity. Thus, many clinical laboratories currently employ a multistep algorithm incorporating a sensitive screening test followed by a specific toxin test. An automated ultrasensitive toxin immunoassay (Singulex Clarity® C. difficile toxins A/B assay) has demonstrated excellent performance compared with cell cytotoxicity neutralization assay (CCNA). In this study, the Clarity assay was evaluated relative to glutamate dehydrogenase (GDH), toxin EIA, toxin B gene PCR, multistep algorithms, and C. difficile culture with ribotyping. Methods Residual clinical stool samples (n = 293) were collected from patients with suspected CDI. The samples were tested on-site with GDH (C. DIFF CHEK™-60), PCR (EntericBio realtime® C. difficile assay), a membrane-type toxin EIA (Tox A/B Quik Chek®), and culture and ribotyping. In total, 188 samples were tested with GDH and 239 samples were tested by PCR. All PCR-positive samples (n = 148) and prospectively tested GDH samples (n = 97) were tested with the toxin EIA. Culture and ribotyping information were available for 205 samples. Results Three of the samples tested gave no result using the Clarity assay and were excluded from the analysis. The Singulex Clarity C. difficile toxins A/B assay had high positive percent agreement (PPA) and low negative percent agreement (NPA) compared with toxin EIA and multistep algorithms ending with toxin EIA. The Clarity assay had high NPA and low PPA compared with PCR, GDH, and the multistep algorithm ending with PCR (figure). Less than 70% of the detected C. difficile PCR positive samples had toxins present. There was no difference in toxin concentration between the ribotypes. Conclusion The Clarity assay had strong PPA compared with toxin EIA and strong NPA compared with PCR. The low NPA and PPA compared with toxin EIA and PCR, respectively, may reflect the poor sensitivity of current toxin EIAs and low specificity of PCR. The Clarity assay detected 30 different ribotype strains, and less than 70% of samples (by PCR) or strains (by ribotyping) had toxins present. The Clarity assay may be considered for use as a standalone test for CDI diagnosis. Disclosures All authors: No reported disclosures.
APA, Harvard, Vancouver, ISO, and other styles
20

Kadhim, Qusay Kanaan, Basman M. Al-Nedawe, and Emad Majeed Hameed. "Encryption and Decryption of Images using GGH Algorithm: Proposed." IOP Conference Series: Materials Science and Engineering 1090, no. 1 (March 1, 2021): 012063. http://dx.doi.org/10.1088/1757-899x/1090/1/012063.

Full text
APA, Harvard, Vancouver, ISO, and other styles
21

Duan, Haohua, Yangyang Liu, Hexiang Huang, Zhengtao Wang, and Hongwei Zhao. "Image Stitching Algorithm for Drones Based on SURF-GHT." IOP Conference Series: Materials Science and Engineering 569 (August 9, 2019): 052025. http://dx.doi.org/10.1088/1757-899x/569/5/052025.

Full text
APA, Harvard, Vancouver, ISO, and other styles
22

Ting, T. O., K. P. Wong, and C. Y. Chung. "Hybrid constrained genetic algorithm/particle swarm optimisation load flow algorithm." IET Generation, Transmission & Distribution 2, no. 6 (2008): 800. http://dx.doi.org/10.1049/iet-gtd:20070224.

Full text
APA, Harvard, Vancouver, ISO, and other styles
23

Zhou, Weijie, Huihui Tao, Feifei Wang, and Weiqiang Pan. "The Optimal Bandwidth Parameter Selection in GPH Estimation." Journal of Mathematics 2021 (December 3, 2021): 1–11. http://dx.doi.org/10.1155/2021/2876000.

Full text
Abstract:
In this paper, the optimal bandwidth parameter is investigated in the GPH algorithm. Firstly, combining with the stylized facts of financial time series, we generate long memory sequences by using the ARFIMA (1, d, 1) process. Secondly, we use the Monte Carlo method to study the impact of the GPH algorithm on existence test, persistence or antipersistence judgment of long memory, and the estimation accuracy of the long memory parameter. The results show that the accuracy of above three factors in the long memory test reached a relatively high level within the bandwidth parameter interval of 0.5 < a < 0.7. For different lengths of time series, bandwidth parameter a = 0.6 can be used as the optimal choice of the GPH estimation. Furthermore, we give the calculation accuracy of the GPH algorithm on existence, persistence or antipersistence of long memory, and long memory parameter d when a = 0.6.
APA, Harvard, Vancouver, ISO, and other styles
24

Sadika, Rjiba, Moez Soltani, and Saloua Benammou. "Comparative study on textual data set using fuzzy clustering algorithms." Kybernetes 45, no. 8 (September 5, 2016): 1232–42. http://dx.doi.org/10.1108/k-11-2015-0301.

Full text
Abstract:
Purpose The purpose of this paper is to apply the Takagi-Sugeno (T-S) fuzzy model techniques in order to treat and classify textual data sets with and without noise. A comparative study is done in order to select the most accurate T-S algorithm in the textual data sets. Design/methodology/approach From a survey about what has been termed the “Tunisian Revolution,” the authors collect a textual data set from a questionnaire targeted at students. Five clustering algorithms are mainly applied: the Gath-Geva (G-G) algorithm, the modified G-G algorithm, the fuzzy c-means algorithm and the kernel fuzzy c-means algorithm. The authors examine the performances of the four clustering algorithms and select the most reliable one to cluster textual data. Findings The proposed methodology was to cluster textual data based on the T-S fuzzy model. On one hand, the results obtained using the T-S models are in the form of numerical relationships between selected keywords and the rest of words constituting a text. Consequently, it allows the authors to interpret these results not only qualitatively but also quantitatively. On the other hand, the proposed method is applied for clustering text taking into account the noise. Originality/value The originality comes from the fact that the authors validate some economical results based on textual data, even if they have not been written by experts in the linguistic fields. In addition, the results obtained in this study are easy and simple to interpret by the analysts.
APA, Harvard, Vancouver, ISO, and other styles
25

Jaqueti Aroca, Jerónimo, Laura M. Molina Esteban, Isabel García-Arata, Jesús García-Martínez, Isabel Cano De Torres, and Santiago Prieto Menchero. "Significance of a polymerase chain reaction method in the detection of Clostridioides difficile." Revista Española de Quimioterapia 34, no. 2 (February 19, 2021): 141–44. http://dx.doi.org/10.37201/req/010.2020.

Full text
Abstract:
Objectives. Clostridioides difficile (CD) is the most common cause of nosocomial diarrhea. Detection of CD toxin in patients’ faecal samples is the traditional rapid method for the diagnosis of CD infection. Various testing algorithms have been proposed: an initial screening test using a rapid test, and a confirmatory test (cytotoxicity neutralization assay, toxigenic culture, nucleic acid amplification test) for discordant results. The aim of this study was to evaluate the effectiveness of a two-step algorithm using an immunochromatographic test followed of a polymerase chain reaction (PCR). Material and methods. The specimens have been tested according to the following schedule: 1) Step one: All samples were tested for detection of glutamate dehydrogenase antigen (GDH) and toxin A/B using the C. diff QUIK CHEK Complete test. All GDH and toxins positive results were considered CD positives; 2) Step two: When the results were discrepant (only GDH+ or toxins+), the samples were confirmed using the PCR test BD MAX Cdiff. All PCR positive results were considered CD positives. Results. A total of 2,138 specimens were initially tested. 139 were positive for GDH and toxins. 160 discrepant results (148 GDH+ and 12 toxins+) were tested by PCR, 117 were positive (107/148 GDH+ and 10/12 toxins+). Conclusions. The implementation of a PCR method showed an increase de 117 positive results (73.1% of discrepant). Considering the sensitivity of C.diff QUIK CHEK (instructions of manufacturer), the GDH discrepant results may be false negatives, y the samples PCR and toxins positives may be real positives results.
APA, Harvard, Vancouver, ISO, and other styles
26

Yang, Chia-Hsiang, Chun-Wei Chou, Chia-Shen Hsu, and Chiao-En Chen. "A Systolic Array Based GTD Processor With a Parallel Algorithm." IEEE Transactions on Circuits and Systems I: Regular Papers 62, no. 4 (April 2015): 1099–108. http://dx.doi.org/10.1109/tcsi.2015.2388831.

Full text
APA, Harvard, Vancouver, ISO, and other styles
27

Javidi, M. "A modified Chebyshev pseudospectral DD algorithm for the GBH equation." Computers & Mathematics with Applications 62, no. 9 (November 2011): 3366–77. http://dx.doi.org/10.1016/j.camwa.2011.08.051.

Full text
APA, Harvard, Vancouver, ISO, and other styles
28

Radojević, Z. M., V. V. Terzija, and M. B. Djurić. "Multipurpose overhead lines protection algorithm." IEE Proceedings - Generation, Transmission and Distribution 146, no. 5 (1999): 441. http://dx.doi.org/10.1049/ip-gtd:19990483.

Full text
APA, Harvard, Vancouver, ISO, and other styles
29

Yih, Jeng Ming. "Supervised Clustering Algorithm for University Student Learning Algebra." Advanced Materials Research 542-543 (June 2012): 1376–79. http://dx.doi.org/10.4028/www.scientific.net/amr.542-543.1376.

Full text
Abstract:
The popular fuzzy c-means algorithm based on Euclidean distance function converges to a local minimum of the objective function, which can only be used to detect spherical structural clusters. Gustafson-Kessel clustering algorithm and Gath-Geva clustering algorithm were developed to detect non-spherical structural clusters. However, Gustafson-Kessel clustering algorithm needs added constraint of fuzzy covariance matrix, Gath-Geva clustering algorithm can only be used for the data with multivariate Gaussian distribution. In GK-algorithm, modified Mahalanobis distance with preserved volume was used. However, the added fuzzy covariance matrices in their distance measure were not directly derived from the objective function. In this paper, an improved Normalized Supervised Clustering Algorithm Based on FCM by taking a new threshold value and a new convergent process is proposed. The experimental results of real data sets show that our proposed new algorithm has the best performance. Not only replacing the common covariance matrix with the correlation matrix in the objective function in the Normalized Supervised Clustering Algorithm.
APA, Harvard, Vancouver, ISO, and other styles
30

Khaleel, Shahbaa I., and Ragad W. Khaled. "Image retrieval based on swarm intelligence." International Journal of Electrical and Computer Engineering (IJECE) 11, no. 6 (December 1, 2021): 5390. http://dx.doi.org/10.11591/ijece.v11i6.pp5390-5401.

Full text
Abstract:
To keep pace with the development of modern technology in this information technology era, and the immense image databases, whether personal or commercial, are increasing, is requiring the management of these databases to strong and accurate systems to retrieve images with high efficiency. Because of the swarm intelligence algorithms are great importance in solving difficult problems and obtaining the best solutions. Here in this research, a proposed system is designed to retrieve color images based on swarm intelligence algorithms. Where the algorithm of the ant colony optimization (ACOM) and the intelligent water drop (IWDM) was used to improve the system's work by conducting the clustering process in these two methods on the features extracted by annular color moment method (ACM) to obtain clustered data, the amount of similarity between them and the query image, is calculated to retrieve images from the database, efficiently and in a short time. In addition, improving the work of these two methods by hybridizing them with fuzzy method, fuzzy gath geva clustering algorithm (FGCA) and obtaining two new high efficiency hybrid algorithms fuzzy ant colony optimization method (FACOM) and fuzzy intelligent water drop method (FIWDM) by retrieving images whose performance values are calculated by calculating the values of precision, recall and the f-measure. It proved its efficiency by comparing it with fuzzy method, FGCA and by methods of swarm intelligence without hybridization, and its work was excellent.
APA, Harvard, Vancouver, ISO, and other styles
31

Stripinis, Linas, and Remigijus Paulavičius. "A new DIRECT-GLh algorithm for global optimization with hidden constraints." Optimization Letters 15, no. 6 (March 29, 2021): 1865–84. http://dx.doi.org/10.1007/s11590-021-01726-z.

Full text
APA, Harvard, Vancouver, ISO, and other styles
32

Wu, Xiaohong, Haoxiang Zhou, Bin Wu, and Tingfei Zhang. "A possibilistic fuzzy Gath-Geva clustering algorithm using the exponential distance." Expert Systems with Applications 184 (December 2021): 115550. http://dx.doi.org/10.1016/j.eswa.2021.115550.

Full text
APA, Harvard, Vancouver, ISO, and other styles
33

Chen, Chin Chun. "Using Mahalanobis Clustering Algorithm for College Student Learning Fundamental Mathematics." Advanced Materials Research 476-478 (February 2012): 2129–32. http://dx.doi.org/10.4028/www.scientific.net/amr.476-478.2129.

Full text
Abstract:
The popular fuzzy c-means algorithm based on Euclidean distance function converges to a local minimum of the objective function, which can only be used to detect spherical structural clusters. Gustafson-Kessel clustering algorithm and Gath-Geva clustering algorithm were developed to detect non-spherical structural clusters. However, Gustafson-Kessel clustering algorithm needs added constraint of fuzzy covariance matrix, Gath-Geva clustering algorithm can only be used for the data with multivariate Gaussian distribution. In GK-algorithm, modified Mahalanobis distance with preserved volume was used. However, the added fuzzy covariance matrices in their distance measure were not directly derived from the objective function. In this paper, an improved Normalized Mahalanobis Clustering Algorithm Based on FCM by taking a new threshold value and a new convergent process is proposed. The experimental results of real data sets show that our proposed new algorithm has the best performance. Not only replacing the common covariance matrix with the correlation matrix in the objective function in the Normalized Mahalanobis Clustering Algorithm Based on FCM.
APA, Harvard, Vancouver, ISO, and other styles
34

Alfa, Michelle J., and Shadi Sepehri. "Combination of Culture, Antigen and Toxin Detection, and Cytotoxin Neutralization Assay for OptimalClostridium difficileDiagnostic Testing." Canadian Journal of Infectious Diseases and Medical Microbiology 24, no. 2 (2013): 89–92. http://dx.doi.org/10.1155/2013/934945.

Full text
Abstract:
BACKGROUND: There has been a growing interest in developing an appropriate laboratory diagnostic algorithm forClostridium difficile, mainly as a result of increases in both the number and severity of cases ofC difficileinfection in the past decade. AC difficilediagnostic algorithm is necessary because diagnostic kits, mostly for the detection of toxins A and B or glutamate dehydrogenase (GDH) antigen, are not sufficient as stand-alone assays for optimal diagnosis ofC difficileinfection. In addition, conventional reference methods forC difficiledetection (eg, toxigenic culture and cytotoxin neutralization [CTN] assays) are not routinely practiced in diagnostic laboratory settings.OBJECTIVE: To review the four-step algorithm used at Diagnostic Services of Manitoba sites for the laboratory diagnosis of toxigenicC difficile.RESULT: One year of retrospectiveC difficiledata using the proposed algorithm was reported. Of 5695 stool samples tested, 9.1% (n=517) had toxigenicC difficile. Sixty per cent (310 of 517) of toxigenicC difficilestools were detected following the first two steps of the algorithm. CTN confirmation of GDH-positive, toxin A- and B-negative assays resulted in detection of an additional 37.7% (198 of 517) of toxigenicC difficile. Culture of the third specimen, from patients who had two previous negative specimens, detected an additional 2.32% (12 of 517) of toxigenicC difficilesamples.DISCUSSION: Using GDH antigen as the screening and toxin A and B as confirmatory test forC difficile, 85% of specimens were reported negative or positive within 4 h. Without CTN confirmation for GDH antigen and toxin A and B discordant results, 37% (195 of 517) of toxigenicC difficilestools would have been missed. Following the algorithm, culture was needed for only 2.72% of all specimens submitted forC difficiletesting.CONCLUSION: The overview of the data illustrated the significance of each stage of this four-stepC difficilealgorithm and emphasized the value of using CTN assay and culture as parts of an algorithm that ensures accurate diagnosis of toxigenicC difficile.
APA, Harvard, Vancouver, ISO, and other styles
35

Salam, Md S., K. M. Nor, and A. R. Hamdan. "Comprehensive algorithm for hydrothermal co-ordination." IEE Proceedings - Generation, Transmission and Distribution 144, no. 5 (1997): 482. http://dx.doi.org/10.1049/ip-gtd:19970819.

Full text
APA, Harvard, Vancouver, ISO, and other styles
36

Sharma, Pranjal, Ankit Agarwal, and Bhawna Chaudhary. "Quantum Genetic Terrain Algorithm (Q-GTA): A Technique to Study the Evolution of the Earth Using Quantum Genetic Algorithm." Proceedings 46, no. 1 (November 17, 2019): 26. http://dx.doi.org/10.3390/ecea-5-06685.

Full text
Abstract:
In recent years, geologists have put in a lot of effort trying to study the evolution of Earth using different techniques studying rocks, gases, and water at different channels like mantle, lithosphere, and atmosphere. Some of the methods include estimation of heat flux between the atmosphere and sea ice, modeling global temperature changes, and groundwater monitoring networks. That being said, algorithms involving the study of Earth’s evolution have been a debated topic for decades. In addition, there is distinct research on the mantle, lithosphere, and atmosphere using isotopic fractionation, which this paper will take into consideration to form genes at the former stage. This factor of isotopic fractionation could be molded in QGA to study the Earth’s evolution. We combined these factors because the gases containing these isotopes move from mantle to lithosphere or atmosphere through gaps or volcanic eruptions contributing to it. We are likely to use the Rb/Sr and Sm/Nd ratios to study the evolution of these channels. This paper, in general, provides the idea of gathering some information about temperature changes by using isotopic ratios as chromosomes, in QGA the chromosomes depict the characteristic of a generation. Here these ratios depict the temperature characteristic and other steps of QGA would be molded to study these ratios in the form of temperature changes, which would further signify the evolution of Earth based on the study that temperature changes with the change in isotopic ratios. This paper will collect these distinct studies and embed them into an upgraded quantum genetic algorithm called Quantum Genetic Terrain Algorithm or Quantum GTA.
APA, Harvard, Vancouver, ISO, and other styles
37

Zhang, Y. M., and R. Kovacevic. "Real-Time Sensing of Sag Geometry During GTA Welding." Journal of Manufacturing Science and Engineering 119, no. 2 (May 1, 1997): 151–60. http://dx.doi.org/10.1115/1.2831090.

Full text
Abstract:
Seam tracking and weld penetration control are two fundamental issues in automated welding. Although the seam tracking technique has matured, the latter still remains a unique unsolved problem. It was found that the full penetration status during GTA welding can be determined with sufficient accuracy using the sag depression. To achieve a new full penetration sensing technique, a structured-light 3D vision system is developed to extract the sag geometry behind the pool. The laser stripe, which is the intersection of the structured-light and weldment, is thinned and then used to acquire the sag geometry. To reduce possible control delay, a small distance is selected between the pool rear and laser stripe. An adaptive dynamic search for rapid thinning of the stripe and the maximum principle of slope difference for unbiased recognition of sag border were proposed to develop an effective real-time image processing algorithm for sag geometry acquisition. Experiments have shown that the proposed sensor and image algorithm can provide reliable feedback information of sag geometry for the full penetration control system.
APA, Harvard, Vancouver, ISO, and other styles
38

Dbeibo, Lana, Joy Williams, Josh Sadowski, William Fadel, Vera Winn, Douglas Houston Webb, and Areeba Kara. "The Impact of Changing to an Algorithm-Based Clostridioides difficile Test on the Decision to Treat Clostridioides difficile." Infection Control & Hospital Epidemiology 41, S1 (October 2020): s407. http://dx.doi.org/10.1017/ice.2020.1058.

Full text
Abstract:
Background: Polymerase chain reaction (PCR) testing for the diagnosis of Clostridioides difficile infection (CDI) detects the presence of the organism; a positive result therefore cannot differentiate between colonization and the pathogenic presence of the bacterium. This may result in overdiagnosis, overtreatment, and risking disruption of microbial flora, which may perpetuate the CDI cycle. Algorithm-based testing offers an advantage over PCR testing as it detects toxin, which allows differentiation between colonization and infection. Although previous studies have demonstrated the clinical utility of this testing algorithm in differentiating infection from colonization, it is unknown whether the test changes CDI treatment decisions. Our facility switched from PCR to an algorithm-based testing method for CDI in June 2018. Objective: In this study, we evaluated whether clinicians’ decisions to treat patients are impacted by a test result that implies colonization (GDH+/Tox−/PCR+ test), and we examined the impact of this decision on patient outcomes. Methods: This is a retrospective cohort study of inpatients with a positive C. diff test between June 2017 and June 2019. The primary outcome was the proportion of patients treated for CDI. We compared this outcome in 3 groups of patients: those with a positive PCR test (June 2017–June 2018), those who had a GDH+/Tox−/PCR+ or a GDH+/Tox+ test result (June 2018–June 2019). Secondary outcomes included toxic megacolon, critical care admission, and mortality in patients with GDH+/Tox−/PCR+ who were treated versus those who were untreated. Results: Of patients with a positive PCR test, 86% were treated with CDI-specific antibiotics, whereas 70.4% with GDH+/Tox+ and 29.25% with GDH+/Tox−/PCR+ result were treated (P < .0001). Mortality was not different between patients with GDH+/Tox−/PCR+ who were treated versus those who were untreated (2.7% vs 3.4%; P = .12), neither was critical care admission within 2 or 7 days of test result (2% vs 1.4%; P = .15) and (4.1% vs 5.4%, P = .39), respectively. There were no cases of toxic megacolon during the study period. Conclusions: The change to an algorithm-based C. difficile testing method had a significant impact on the clinicians’ decisions to treat patients with a positive test, as most patients with a GDH+/Tox−/PCR+ result did not receive treatment. These patients did not suffer more adverse outcomes compared to those who were treated, which has implications for testing practices. It remains to be explored whether clinicians are using clinical criteria to decide whether or not to treat patients with a positive algorithm-based test, as opposed to the more reflexive treatment of patients with a positive PCR test.Funding: NoneDisclosures: None
APA, Harvard, Vancouver, ISO, and other styles
39

Thamilselvan, R., and P. Balasubramanie. "Integrating Genetic Algorithm with a Tabu Search (GTA) for Network Traffic Scheduling." International Journal of Computer Applications 72, no. 6 (June 26, 2013): 21–24. http://dx.doi.org/10.5120/12498-8234.

Full text
APA, Harvard, Vancouver, ISO, and other styles
40

Bahrampour, S., K. Salahshour, and B. Moshiri. "Distributed Fault Detection and Isolation Algorithm Using Modified Gath-Geva Clustering Technique." IFAC Proceedings Volumes 42, no. 8 (2009): 858–63. http://dx.doi.org/10.3182/20090630-4-es-2003.00141.

Full text
APA, Harvard, Vancouver, ISO, and other styles
41

Jafarabadi Ashtiani, Hamid, Haidar Samet, and Teymoor Ghanbari. "Simple current-based algorithm for directional relays." IET Generation, Transmission & Distribution 11, no. 17 (November 30, 2017): 4227–37. http://dx.doi.org/10.1049/iet-gtd.2017.0058.

Full text
APA, Harvard, Vancouver, ISO, and other styles
42

Wong, K. P., A. Li, and T. M. Y. Law. "Advanced, constrained, genetic algorithm load flow method." IEE Proceedings - Generation, Transmission and Distribution 146, no. 6 (1999): 609. http://dx.doi.org/10.1049/ip-gtd:19990638.

Full text
APA, Harvard, Vancouver, ISO, and other styles
43

Lin, W. M., F. S. Cheng, and M. T. Tsay. "Distribution feeder reconfiguration with refined genetic algorithm." IEE Proceedings - Generation, Transmission and Distribution 147, no. 6 (2000): 349. http://dx.doi.org/10.1049/ip-gtd:20000715.

Full text
APA, Harvard, Vancouver, ISO, and other styles
44

Aldridge, C. J., S. McKee, J. R. McDonald, S. J. Galloway, K. P. Dahal, M. E. Bradley, and J. F. Macqueen. "Knowledge-based genetic algorithm for unit commitment." IEE Proceedings - Generation, Transmission and Distribution 148, no. 2 (2001): 146. http://dx.doi.org/10.1049/ip-gtd:20010022.

Full text
APA, Harvard, Vancouver, ISO, and other styles
45

Echavarren, F. M., E. Lobato, and L. Rouco. "Contingency analysis: feasibility identification and calculation algorithm." IEE Proceedings - Generation, Transmission and Distribution 152, no. 5 (2005): 645. http://dx.doi.org/10.1049/ip-gtd:20045009.

Full text
APA, Harvard, Vancouver, ISO, and other styles
46

Soroudi, A., and M. Ehsan. "Imperialist competition algorithm for distributed generation connections." IET Generation, Transmission & Distribution 6, no. 1 (2012): 21. http://dx.doi.org/10.1049/iet-gtd.2011.0190.

Full text
APA, Harvard, Vancouver, ISO, and other styles
47

Lin, Sheng-Kai, Rong-Chin Lo, and Ren-Guey Lee. "MAGNETOENCEPHALOGRAPHY–ELECTROENCEPHALOGRAPHY CO-REGISTRATION USING 3D GENERALIZED HOUGH TRANSFORM." Biomedical Engineering: Applications, Basis and Communications 32, no. 03 (June 2020): 2050024. http://dx.doi.org/10.4015/s1016237220500246.

Full text
Abstract:
This study proposes an advanced co-registration method for an integrated high temporal resolution electroencephalography (EEG) and magnetoencephalography (MEG) data. The MEG has a higher accuracy for source localization techniques and spatial resolution by sensing magnetic fields generated by the entire brain using multichannel superconducting quantum interference devices, whereas EEG can record electrical activities from larger cortical surface to detect epilepsy. However, by integrating the two modality tools, we can accurately localize the epileptic activity compared to other non-invasive modalities. Integrating the two modality tools is challenging and important. This study proposes a new algorithm using an extended three-dimensional generalized Hough transform (3D GHT) to co-register the two modality data. The pre-process steps require the locations of EEG electrodes, MEG sensors, head-shape points of subjects and fiducial landmarks. The conventional GHT algorithm is a well-known method used for identifying or locating two 2D images. This study proposes a new co-registration method that extends the 2D GHT algorithm to a 3D GHT algorithm that can automatically co-register 3D image data. It is important to study the prospective brain source activity in bio-signal analysis. Furthermore, the study examines the registration accuracy evaluation by calculating the root mean square of the Euclidean distance of MEG–EEG co-registration data. Several experimental results are used to show that the proposed method for co-registering the two modality data is accurate and efficient. The results demonstrate that the proposed method is feasible, sufficiently automatic, and fast for investigating brain source images.
APA, Harvard, Vancouver, ISO, and other styles
48

Ivanyos, Gábor, Marek Karpinski, Lajos Rónyai, and Nitin Saxena. "Trading GRH for algebra: Algorithms for factoring polynomials and related structures." Mathematics of Computation 81, no. 277 (January 1, 2012): 493–531. http://dx.doi.org/10.1090/s0025-5718-2011-02505-6.

Full text
APA, Harvard, Vancouver, ISO, and other styles
49

Piatti, Gabriella, Marco Bruzzone, Vincenzo Fontana, and Marcello Ceppi. "Analysis of Routine and Integrative Data from Clostridioides difficile Infection Diagnosis and the Consequent Observations." Open Microbiology Journal 13, no. 1 (December 31, 2019): 343–49. http://dx.doi.org/10.2174/1874285801913010343.

Full text
Abstract:
Background: Clostridioides difficile Infection (CDI) is an acute disease that needs a fast proper treatment. Unfortunately, the diagnosis, and above all the understanding of the results, remain arduous. Objective: This study analyzed routine and integrative results of all fecal samples from patients over time. Our aim was to understand the dynamics of CDI infection and the meaning of “difficult to interpret” results, to make physicians better understand the various tools they can use. Methods: We evaluated routine results obtained from 815 diarrheal stools with Enzyme Immunoassay (EIA) that detects C. difficile Glutamate Dehydrogenase (GDH) antigen and toxin B. We also reanalyzed a part of samples using integrative tests: a Real-time polymerase chain reaction (RT-PCR) for C. difficile toxin B gene (tcdB) and the automated immunoassay VIDAS C. difficile system for GDH and toxins A/B. Results: EIA GDH positivity increased through multiple testing over time, with a P value <0.001, depicting a sort of bacterial growth curve. Eighty-five percent of GDH positive/toxin B negative, i.e., discrepant, samples PCR were tcdB positive, 61.5% of discrepant tcdB positive samples were VIDAS toxins A/B positive, and 44.4% of GDH EIA negative stools were VIDAS GDH positive. Conclusion: The results confirmed the low sensitivity of the EIA system for C. difficile GDH and toxins, questioned the use of the latter for concluding any CDI diagnostic algorithm, and led us to indicate the algorithm beginning with tcdB molecular research, and continuing in positive cases with VIDAS CD GDH method, as the most effective for CDI.
APA, Harvard, Vancouver, ISO, and other styles
50

Brown, Johanna P., and Stephanie Puckett. "100. Development and Implementation of a 2-Tier Testing Algorithm for Clostridioides difficile: An Evaluation of Outcomes on Patients with Indeterminate Results at 90 Days." Open Forum Infectious Diseases 7, Supplement_1 (October 1, 2020): S64—S65. http://dx.doi.org/10.1093/ofid/ofaa439.145.

Full text
Abstract:
Abstract Background There is no definitive gold standard for accurate diagnosis of Clostridioides difficile (C difficile) infection. There is ample evidence that relying on a molecular test such as Polymerase Chain Reaction (PCR) for diagnosis, can lead to over diagnosis and unnecessary treatment. Combined, multi-step algorithms have been proposed to improve specificity of testing. The challenge remains in interpreting discordant or indeterminate results. Additionally, the risk of hospitalization due to lack of treatment for indeterminate results remains unclear. Methods To improve C difficile testing, a new 2-tier algorithm was implemented in 2019 starting with PCR testing. An indeterminate result was defined as a sample with a positive PCR and a positive Glutamate Dehydrogenase (GDH)/negative toxin result or a positive PCR and a negative GDH/positive toxin result. Indeterminate results were classified by episode severity and number. Patient records were reviewed by the Antimicrobial Stewardship (AS) physician and pharmacist to determine true infection versus colonization. Treatment was given as per recent IDSA Guidelines. All patients with indeterminate results were followed for 90 days for development of infection or hospitalization due to C difficile. Adults with stool samples submitted for testing between 6/1/2019 and 12/31/2019 were included. A total of 169 specimens were reviewed: 75 were positive, 72 were indeterminate (4 excluded from final analysis) and 22 were negative. Results Using a 2-tier testing algorithm, 68 (41%) of all results were indeterminate. Our AS classified 47 (69%) of those as infection and 21 (31%) as colonization. Patients with indeterminate results who were treated had a low incidence (8.5%) of reinfection requiring hospitalization in the following 90 days. There were no hospitalizations in the untreated group. Of patients with an indeterminate result who were treated, 42 (89%) were categorized as an initial episode of C difficile infection. Conclusion Clinical correlation of indeterminate results is critical to algorithm interpretation. A combined approach with provider education, an electronic testing advisor, a 2-tier testing algorithm, daily monitoring and prescribing by the AS team resulted in favorable outcomes for patients with indeterminate results Disclosures All Authors: No reported disclosures
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography