Готові списки джерел за темами / Clusters detection

Добірка наукової літератури з теми "Clusters detection"

Автор: Grafiati
Опубліковано: 15 червня 2024

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями

Оберіть тип джерела:

Ознайомтеся зі списками актуальних статей, книг, дисертацій, тез та інших наукових джерел на тему "Clusters detection".

Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.

Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.

Зміст

  1. Статті в журналах
  2. Дисертації
  3. Книги
  4. Частини книг
  5. Тези доповідей конференцій
  6. Звіти організацій

Статті в журналах з теми "Clusters detection":

1

AHMAD, WASEEM, and AJIT NARAYANAN. "OUTLIER DETECTION USING HUMORAL-MEDIATED CLUSTERING (HAIS)." International Journal of Computational Intelligence and Applications 11, no. 01 (March 2012): 1250003. http://dx.doi.org/10.1142/s1469026812500034.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Outlier detection has important applications in various data mining domains such as fraud detection, intrusion detection, customers' behavior and employees' performance analysis. Outliers are characterized by being significantly or "interestingly" different from the rest of the data. In this paper, a novel cluster-based outlier detection method is proposed using a humoral-mediated clustering algorithm (HAIS) based on concepts of antibody secretion in natural immune systems. The proposed method finds meaningful clusters as well as outliers simultaneously. This is an iterative approach where only clusters above threshold (larger sized clusters) are carried forward to the next cycle of cluster formation while removing small sized clusters. This paper also demonstrates through experimental results that the mere existence of outliers severely affects the clustering outcome, and removing those outliers can result in better clustering solutions. The feasibility of the method is demonstrated through simulated datasets, current datasets from the literature as well as a real-world doctors' performance evaluation dataset where the task is to identify potentially under-performing doctors. The results indicate that HAIS has capabilities of detecting single point as well as cluster-based outliers.
2

Xu, Weiwei, Miriam E. Ramos-Ceja, Florian Pacaud, Thomas H. Reiprich, and Thomas Erben. "Catalog of X-ray-selected extended galaxy clusters from the ROSAT All-Sky Survey (RXGCC)." Astronomy & Astrophysics 658 (February 2022): A59. http://dx.doi.org/10.1051/0004-6361/202140908.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Context. There is a known tension between cosmological parameter constraints obtained from the primary cosmic microwave background and those drawn from galaxy cluster samples. One possible explanation for this discrepancy may be that the incomplete character of detected clusters is higher than estimated and, as a result, certain types of groups or galaxy clusters have been overlooked in the past. Aims. We aim to search for galaxy groups and clusters with particularly extended surface brightness distributions by creating a new X-ray-selected catalog of extended galaxy clusters from the ROSAT All-Sky Survey (RASS), based on a dedicated source detection and characterization algorithm that is optimized for extended sources. Methods. Our state-of-the-art algorithm includes multi-resolution filtering, source detection, and characterization. On the basis of extensive simulations, we investigated the detection efficiency and sample purity. We used previous cluster catalogs in X-ray and other bands, as well as spectroscopic and photometric redshifts of galaxies to identify clusters. Results. We report a catalog of galaxy clusters at high galactic latitude based on the ROSAT All-sky Survey, known as the RASS-based extended X-ray Galaxy Cluster Catalog, which includes 944 groups and clusters. Of this number, 641 clusters have been previously identified based on intra-cluster medium (ICM) emission (Bronze), 154 known optical and infrared clusters are detected as X-ray clusters for the first time (Silver) and 149 are identified as clusters for the first time (Gold). Based on 200 simulations, the contamination ratio of the detections that were identified as clusters by ICM emission and the detections that were identified as optical and infrared clusters in previous work is 0.008 and 0.100, respectively. Compared with the Bronze sample, the Gold+Silver sample is less luminous, less massive, and exhibits a flatter surface brightness profile. Specifically, the median flux in [0.1−2.4] keV band for Gold+Silver and Bronze sample is 2.496 × 10−12 erg s−1 cm−2 and 4.955 × 10−12 erg s−1 cm−2, respectively. The median value of β (the slope of cluster surface brightness profile) is 0.76 and 0.83 for the Gold+Silver and Bronze sample, respectively.
3

Reduzzi, Carolina, Serena Di Cosimo, Lorenzo Gerratana, Rosita Motta, Antonia Martinetti, Andrea Vingiani, Paolo D’Amico, et al. "Circulating Tumor Cell Clusters Are Frequently Detected in Women with Early-Stage Breast Cancer." Cancers 13, no. 10 (May 13, 2021): 2356. http://dx.doi.org/10.3390/cancers13102356.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
The clinical relevance of circulating tumor cell clusters (CTC-clusters) in breast cancer (BC) has been mostly studied using the CellSearch®, a marker-dependent method detecting only epithelial-enriched clusters. However, due to epithelial-to-mesenchymal transition, resorting to marker-independent approaches can improve CTC-cluster detection. Blood samples collected from healthy donors and spiked-in with tumor mammospheres, or from BC patients, were processed for CTC-cluster detection with 3 technologies: CellSearch®, CellSieve™ filters, and ScreenCell® filters. In spiked-in samples, the 3 technologies showed similar recovery capability, whereas, in 19 clinical samples processed in parallel with CellSearch® and CellSieve™ filters, filtration allowed us to detect more CTC-clusters than CellSearch® (median number = 7 versus 1, p = 0.0038). Next, samples from 37 early BC (EBC) and 23 metastatic BC (MBC) patients were processed using ScreenCell® filters for attaining both unbiased enrichment and marker-independent identification (based on cytomorphological criteria). At baseline, CTC-clusters were detected in 70% of EBC cases and in 20% of MBC patients (median number = 2, range 0–20, versus 0, range 0–15, p = 0.0015). Marker-independent approaches for CTC-cluster assessment improve detection and show that CTC-clusters are more frequent in EBC than in MBC patients, a novel finding suggesting that dissemination of CTC-clusters is an early event in BC natural history.
4

Mas, J.-F., A. Pérez Vega, and A. Ghilardi. "EFFECT OF THE DELAY IN THE REPORTS OF COVID-19 CASES ON NEAR REAL-TIME CLUSTERS DETECTION." International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLVIII-1/W2-2023 (December 13, 2023): 457–62. http://dx.doi.org/10.5194/isprs-archives-xlviii-1-w2-2023-457-2023.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Abstract. The COVID-19 pandemic has strongly impacted the vast majority of countries in the world. As of today (April 12th, 2023), more than 762 million confirmed cases and nearly 6.9 million deaths are considered widely underestimated. During a pandemic, detecting clusters of patients is crucial to allocate resources and aiding decision-making better as emergent outbreaks continue to grow. However, delays in reporting suspected or confirmed cases can affect the detection of clusters in near real-time. This study aimed to assess whether the delays in reporting COVID-19 in Mexico presented specific Spatiotemporal patterns and whether they significantly affected the detection of clusters. To do this, we used the daily records of the Mexican Ministry of Health for three dates at the beginning and during the increase in cases of the fourth wave (January 2022). We compared the clusters obtained using the data available on the same date and during the following days, including delayed data. We carried out cluster detection using the flexible spatial scan statistic (FlexScan) on the R platform. The results indicate that the spatial distribution of delays was heterogeneous and that delays affect cluster detection.
5

Baker, Meghan A., Deborah S. Yokoe, John Stelling, Ken Kleinman, Rebecca E. Kaganov, Alyssa R. Letourneau, Neha Varma, et al. "Automated outbreak detection of hospital-associated pathogens: Value to infection prevention programs." Infection Control & Hospital Epidemiology 41, no. 9 (June 10, 2020): 1016–21. http://dx.doi.org/10.1017/ice.2020.233.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
AbstractObjective:To assess the utility of an automated, statistically-based outbreak detection system to identify clusters of hospital-acquired microorganisms.Design:Multicenter retrospective cohort study.Setting:The study included 43 hospitals using a common infection prevention surveillance system.Methods:A space–time permutation scan statistic was applied to hospital microbiology, admission, discharge, and transfer data to identify clustering of microorganisms within hospital locations and services. Infection preventionists were asked to rate the importance of each cluster. A convenience sample of 10 hospitals also provided information about clusters previously identified through their usual surveillance methods.Results:We identified 230 clusters in 43 hospitals involving Gram-positive and -negative bacteria and fungi. Half of the clusters progressed after initial detection, suggesting that early detection could trigger interventions to curtail further spread. Infection preventionists reported that they would have wanted to be alerted about 81% of these clusters. Factors associated with clusters judged to be moderately or highly concerning included high statistical significance, large size, and clusters involving Clostridioides difficile or multidrug-resistant organisms. Based on comparison data provided by the convenience sample of hospitals, only 9 (18%) of 51 clusters detected by usual surveillance met statistical significance, and of the 70 clusters not previously detected, 58 (83%) involved organisms not routinely targeted by the hospitals’ surveillance programs. All infection prevention programs felt that an automated outbreak detection tool would improve their ability to detect outbreaks and streamline their work.Conclusions:Automated, statistically-based outbreak detection can increase the consistency, scope, and comprehensiveness of detecting hospital-associated transmission.
6

Too, L. S., J. Pirkis, A. Milner, and M. J. Spittal. "Clusters of suicides and suicide attempts: detection, proximity and correlates." Epidemiology and Psychiatric Sciences 26, no. 5 (June 9, 2016): 491–500. http://dx.doi.org/10.1017/s2045796016000391.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Background.A suicide cluster is defined as a higher number of observed cases occurring in space and/or time than would typically be expected. Previous research has largely focused on identifying clusters of suicides, while there has been comparatively limited research on clusters of suicide attempts. We sought to identify clusters of both types of behaviour, and having done that, identify the factors that distinguish suicide attempts inside a cluster from those that were outside a cluster.Methods.We used data from Western Australia from 2000 to 2011. We defined suicide attempts as admissions to hospital for deliberate self-harm and suicides as deaths due to deliberate self-harm. Using an analytic strategy that accounted for the repetition of attempted suicide within a cluster, we performed spatial-temporal analysis using Poisson discrete scan statistics to detect clusters of suicide attempts and clusters of suicides. Logistic regression was then used to compare clustered attempts with non-clustered attempts to identify risk factors for an attempt being in a cluster.Results.We detected 350 (1%) suicide attempts occurring within seven spatial-temporal clusters and 12 (0.6%) suicides occurring within two spatial-temporal clusters. Both of the suicide clusters were located within a larger but later suicide attempt cluster. In multivariate analysis, suicide attempts by individuals who lived in areas of low socioeconomic status had higher odds of being in a cluster than those living in areas of high socioeconomic status [odds ratio (OR) = 29.1, 95% confidence interval (CI) = 6.3–135.5]. A one percentage-point increase in the proportion of people who had changed address in the last year was associated with a 60% increase in the odds of the attempt being within a cluster (OR = 1.60, 95% CI = 1.29–1.98) and a one percentage-point increase in the proportion of Indigenous people in the area was associated with a 7% increase in the suicide being within a cluster (OR = 1.07, 95% CI = 1.00–1.13). Age, sex, marital status, employment status, method of harm, remoteness, percentage of people in rented accommodation and percentage of unmarried people were not associated with the odds of being in a suicide attempt cluster.Conclusions.Early identification of and responding to suicide clusters may reduce the likelihood of subsequent clusters forming. The mechanisms, however, that underlie clusters forming is poorly understood.
7

Barthakur, Pijush, Manoj Dahal, and Mrinal Kanti Ghose. "CluSiBotHealer: Botnet Detection through Similarity Analysis of Clusters." Journal of Advances in Computer Networks 3, no. 1 (2015): 49–55. http://dx.doi.org/10.7763/jacn.2015.v3.141.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Kremer, Kyle, Dongzi Li, Wenbin Lu, Anthony L. Piro, and Bing Zhang. "Prospects for Detecting Fast Radio Bursts in the Globular Clusters of Nearby Galaxies." Astrophysical Journal 944, no. 1 (February 1, 2023): 6. http://dx.doi.org/10.3847/1538-4357/acabbf.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Abstract The recent detection of a repeating fast radio burst (FRB) in an old globular cluster in M81 challenges traditional FRB formation mechanisms based on the magnetic activity of young neutron stars formed in core-collapse supernovae. Furthermore, the detection of this repeater in such a nearby galaxy implies a high local universe rate of similar events in globular clusters. Building off the properties inferred from the M81 FRB, we predict the number of FRB sources in nearby (d ≲ 20 Mpc) galaxies with large globular cluster systems known. Incorporating the uncertain burst energy distribution, we estimate the rate of bursts detectable in these galaxies by radio instruments such as FAST and MeerKat. Of all local galaxies, we find M87 is the best candidate for FRB detections. We predict that M87's globular cluster system contains  ( 10 ) FRB sources at present and that a dedicated radio survey (by either FAST or MeerKat) of  ( 10 ) hr has a 90% probability of detecting a globular cluster FRB in M87. The detection of even a handful of additional globular cluster FRBs would provide invaluable constraints on FRB mechanisms and population properties. Previous studies have demonstrated young neutron stars formed following the collapse of dynamically formed massive white dwarf binary mergers may provide the most natural mechanism for these bursts. We explore the white dwarf merger scenario using a suite of N-body cluster models, focusing in particular on such mergers in M87's clusters. We describe a number of outstanding features of this scenario that in principle may be testable with an ensemble of observed FRBs in nearby globular clusters.
9

Mirmelstein, M., M. Shimon, and Y. Rephaeli. "Detection likelihood of cluster-induced CMB polarization." Astronomy & Astrophysics 644 (November 30, 2020): A36. http://dx.doi.org/10.1051/0004-6361/201834657.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Nearby galaxy clusters can potentially induce sub-microkelvin polarization signals in the cosmic microwave background (CMB) at characteristic scales of a few arcminutes. We explore four such polarization signals induced in a rich nearby fiducial cluster and calculate the likelihood of their detection by a telescope project with capabilities such as those of the Simons Observatory (SO). In our feasibility analysis, we include instrumental noise, primordial CMB anisotropy, statistical thermal Sunyaev-Zeldovich (SZ) cluster signal, and point source confusion, assuming a few percent of the nominal telescope observation time of an SO-like project. Our analysis indicates that the thermal SZ intensity can be sensitively mapped in rich nearby clusters and that the kinematic SZ intensity can be measured with high statistical significance toward a fast moving nearby cluster. The detection of polarized SZ signals will be quite challenging but could still be feasible toward several very rich nearby clusters with very high SZ intensity. The polarized SZ signal from a sample of ∼20 clusters can be statistically detected at S/N ∼ 3, if observed for several months.
10

Masuda, Ryo, and Ryo Inoue. "Point Event Cluster Detection via the Bayesian Generalized Fused Lasso." ISPRS International Journal of Geo-Information 11, no. 3 (March 11, 2022): 187. http://dx.doi.org/10.3390/ijgi11030187.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Spatial cluster detection is one of the focus areas of spatial analysis, whose objective is the identification of clusters from spatial distributions of point events aggregated in districts with small areas. Choi et al. (2018) formulated cluster detection as a parameter estimation problem to leverage the parameter selection capability of the sparse modeling method called the generalized fused lasso. Although this work is superior to conventional methods for detecting multiple clusters, its estimation results are limited to point estimates. This study therefore extended the above work as a Bayesian cluster detection method to describe the probabilistic variations of clustering results. The proposed method combines multiple sparsity-inducing priors and encourages sparse solutions induced by the generalized fused lasso. Evaluations were performed with simulated and real-world distributions of point events to demonstrate that the proposed method provides new information on the quantified reliabilities of clustering results at the district level while achieving comparable detection performances to that of the previous work.
Більше джерел
Також вас можуть зацікавити розширені добірки на тему "Clusters detection" для конкретних типів джерел:
Статті в журналах Дисертації Книги

Дисертації з теми "Clusters detection":

1

Farrens, S. "Optical detection of galaxy clusters." Thesis, University College London (University of London), 2011. http://discovery.ucl.ac.uk/1318077/.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
This thesis first presents a relatively straight forward approach for detecting galaxy clusters using spectroscopic data. A friend-of-friends algorithm based on that of Huchra & Geller (1982) is implemented with linking parameters that take into account selection effects on the the 2dF-SDSS and QSO (2SLAQ) Luminous Red Galaxy Survey (Cannon et al. 2006). The linking parameters are constrained using a mock halo catalogue. The galaxy groups and clusters found with this method have an average velocity dispersion of \sigma v = 467:97 kms-1 and an average size of R clt = 0:78 h-1Mpc. Cluster masses are estimated using the cluster velocity dispersions and appear consistent with values expected for genuine structures. The spectroscopic cluster catalogue is then used to calibrate and compare with a more complex method for detecting clusters using photometric redshifts based on the method of Botzler et al. (2004). The spectroscopic cluster catalogue can be reproduced by around 38% and up to 80% if matching is made only to groups and clusters with six or more members. This code is also applied to the Megaz-LRG DR7 catalogue (Collister & Lahav 2004) producing two catalogues. One that appears to have a good level of completeness relative to the 2SLAQ spectroscopic catalogue. A spectroscopic follow up of some preliminary results from the photometric cluster finder was made using the Anglo-Australian Telescope, which show that the majority of the clusters analysed are genuine and approximate masses can be estimated from the cluster velocity dispersions. Finally, some initials results from on going work in the Dark Energy Survey collaboration are presented, which cover simulated galaxy photometric redshift and colour analysis as well as cluster detection.
2

Mundnich, Batic Karel Bogomir. "Early detection of high volatility clusters using particle filters." Tesis, Universidad de Chile, 2013. http://www.repositorio.uchile.cl/handle/2250/115486.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Ingeniero Civil Electricista
El presente trabajo explora y analiza el uso de herramientas de procesamiento de señales que son comunes en áreas de Ingeniería Eléctrica y Pronóstico y Gestión de Salud en el análisis de series de tiempo financieras. El objetivo principal de este trabajo es detectar eventos de alto riesgo en una etapa temprana. De esta forma, el algoritmo propuesto emplea la fuerte relación entre volatilidad y riesgo y detecta clusters de alta volatilidad mediante el uso de la información obtenida de los procesos de estimación a través de Filtro de Partículas. Para alcanzar el objetivo mencionado, se utiliza la representación de espacio-estado estocástica uGARCH para modelar la volatilidad de retornos compuestos continuamente. Dada la no-observabilidad de la volatilidad, se implementan dos esquemas de Filtro de Partículas para su estimación: los enfoques clásico y sensible al riesgo. Este último incluye el uso de una Distribución de Pareto Generalizada como propuesta para el funcional de riesgo (y distribución de importancia) para asegurar la asignación de partículas en regiones del espacio-estado que están asociadas a variaciones rápidas de volatilidad del sistema. Para evaluar correctamente el rendimiento de las rutinas de filtrado, se han generado seis conjuntos de datos, donde ambos el estado y las mediciones son conocidas. Además, se ha realizado un análisis de sensibilidad sobre los seis conjuntos de datos, para así obtener los parámetros que permiten la mejor estimación de volatilidad. De estos resultados, se calculan valores promedios de parámetros que son luego utilizados en el esquema de detección. La etapa de detección explora tres diferentes técnicas. Primero, se propone la utilización de un test de hipótesis entre las estimaciones a priori y a posteriori de las distribuciones de probabilidad del Filtro de Partículas Sensible al Riesgo. Segundo, se utiliza el Discriminante de Fisher para comparar las estimaciones a posteriori de las densidades entre el Filtro de Partículas Clásico y el Sensible al Riesgo. Finalmente, se utiliza la Divergencia de Kullback-Leibler de la misma forma que el Discriminante de Fisher. Los algoritmos propuestos son probados en los datos generados artificialmente y en datos de acciones de IBM. Los resultados demuestran que el Filtro de Partículas Sensible al Riesgo propuesto supera la precisión del Filtro de Partículas en momentos de alzas no esperadas de volatilidad. Por otra parte, el test de hipótesis empleado en el proceso de filtrado sensible al riesgo detecta correctamente la mayoría de las alzas repentinas de volatilidad que conducen a la detección temprana de clusters de alta volatilidad. Finalmente, los algoritmos de detección propuestos basados en Discriminante de Fisher y Divergencia de Kullback-Leibler llevan a resultados donde la detección no es posible.
3

Crawford, Carolin Susan. "The detection of distant cooling flows." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293490.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
4

McLoughlin, Kirstin J. "Computer aided detection of microcalcification clusters in digital mammogram images." Thesis, University of Canterbury. Electrical and Computer Engineering, 2004. http://hdl.handle.net/10092/6536.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Recent advancements in computer technology have ensured that early detection of breast cancer, via computer aided detection (CAD) schemes, has become a rapidly expanding field of research. There is a desire to improve the detection accuracy of breast cancer without increasing the number of falsely identified cancers. The CAD scheme considered here is intended to assist radiologists in the detection of micro calcification clusters, providing a real contribution to the mammography screening process. Factors that affect the detection accuracy of micro calcifications in digital mammograms include the presence of high spatial frequency noise, and locally linear high intensity structures known as curvilinear structures (CLS). The two issues considered are how to compensate for the high frequency image noise and how to detect CLS thus removing their influence on micro calcification detection. First, an adaptive approach to modelling the image noise is adopted. This is derived directly from each mammogram and is adaptable to varying imaging conditions. It is found that compensating for the high frequency image noise significantly improves micro calcification detection accuracy. Second, due to the varying size and orientation of CLS in mammogram images, a shape parameter is designed for their detection using a multiresolution wavelet filter bank. The shape parameter leads to an efficient way of distinguishing curvilinear structures from faint micro calcifications. This improves micro calcification detection performance by reducing the number of false positive detections related to CLS. The detection and segmentation of micro calcification clusters is achieved by the development of a stochastic model, which classifies individual pixels within a mammogram into separate classes based on Bayesian decision theory. Both the high frequency noise model and CLS shape parameters are used as input to this segmentation process. The CAD scheme is specifically designed to be independent of the modality used, simultaneously exploiting the image data and prior knowledge available for micro calcification detection. A new hybrid clustering scheme enables the distinction between individual and clustered micro calcifications, where clustered micro calcifications are considered more clinically suspicious. The scheme utilises the observed properties of genuine clusters (such as a uniform distribution) providing a practical approach to the clustering process. The results obtained are encouraging with a high percentage of genuine clusters detected at the expense of very few false positive detections. An extensive performance evaluation of the CAD scheme helps determine the accuracy of the system and hence the potential contribution to the mammography screening process. Comparing the CAD scheme developed with previously developed micro calcification detection schemes shows that the performance of this method is highly competitive. The best results presented here give a sensitivity of 91% at an average false positive detection rate of 0.8 false positives per image.
5

Forsberg, Viktor. "AUTOMATIC ANOMALY DETECTION AND ROOT CAUSE ANALYSIS FOR MICROSERVICE CLUSTERS." Thesis, Umeå universitet, Institutionen för datavetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-164740.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Large microservice clusters deployed in the cloud can be very difficult to both monitor and debug. Monitoring theses clusters is a fi€rst step towards detection of anomalies, deviations from normal behaviour. Anomalies are oft‰en indicators that a component is failing or is about to fail and should hence be detected as soon as possible. Th‘ere are oft‰en lots of metrics available to view. Furthermore, any errors that occur oft‰en propagate to other microservices making it hard to manually locate the root cause of an anomaly, because of this automatic methods are needed to detect and correct the problems. Th‘e goal of this thesis is to create a solution that can automatically monitor a microservice cluster, detect anomalies, and fi€nd a root cause. Th‘e anomaly detection is based on an unsupervised clustering algorithm that learns the normal behaviour of each service and then look for data that falls outside that behaviour. Once an anomaly is detected the proposed method tries to match the data against prede€fined root causes. ‘The proposed solution is evaluated in a real microservice cluster deployed in the cloud, using Kubernetes together with a service mesh and several other tools to help gather metrics and trace requests in the system.
6

Burato, Dario <1993&gt. "Load balancing and fault early detection for Apache Kafka clusters." Master's Degree Thesis, Università Ca' Foscari Venezia, 2019. http://hdl.handle.net/10579/15159.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Apache Kafka is a publish-subscribe message system, producers publish data to a cluster and clients subscribes to receive data. The messages are sent by their producers and stored in partitions, the load balancing is performed thanks to their distribution between the cluster's nodes. The component which assign a message to a partition is called partitioner, located inside every producer. When partitions lacks intrinsic meaning, and are used purely for load-balancing purposes, the default partitioners available with Apache Kafka aim only to get the same amount of messages shared between partitions. The most common Apache Kafka cluster configuration is based on multiple identical systems, when a cluster is updated with new more performing components the old ones are usually removed. Even if re-balancing tools exists, it would take time to properly adapt to an hybrid cluster configuration, this is caused by partitioners focus on data amount rather than node performance. The problem could be solved by changing the amount of partitions in each old and new system, matching their performance ratio, thus tricking the default partitioner logic, but this actually could hurt client performance. A proper partitioner which knows the performance of each cluser's node is a correct solution, this document will present a formal method to detect problematic scenarios and a custom partitioner that adapts to them.
7

Toni, Greta. "Detection and characterization of galaxy clusters in the COSMOS field with the AMICO algorithm." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amslaurea.unibo.it/25229/.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
In this work we made use of the AMICO algorithm to detect clusters in COSMOS2015, a photometric galaxy catalogue of the COSMOS field (Laigle+16). We divided our study in two different analyses being the cluster search on r-band photometry in the range 0
8

Marshall, J. Brooke. "Prospective Spatio-Temporal Surveillance Methods for the Detection of Disease Clusters." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/29639.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
In epidemiology it is often useful to monitor disease occurrences prospectively to determine the location and time when clusters of disease are forming. This aids in the prevention of illness and injury of the public and is the reason spatio-temporal disease surveillance methods are implemented. Care must be taken in the design and implementation of these types of surveillance methods so that the methods provide accurate information on the development of clusters. Here two spatio-temporal methods for prospective disease surveillance are considered. These include the local Knox monitoring method and a new wavelet-based prospective monitoring method. The local Knox surveillance method uses a cumulative sum (CUSUM) control chart for monitoring the local Knox statistic, which tests for space-time clustering each time there is an incoming observation. The detection of clusters of events occurring close together both temporally and spatially is important in finding outbreaks of disease within a specified geographic region. The local Knox surveillance method is based on the Knox statistic, which is often used in epidemiology to test for space-time clustering retrospectively. In this method, a local Knox statistic is developed for use with the CUSUM chart for prospective monitoring so that epidemics can be detected more quickly. The design of the CUSUM chart used in this method is considered by determining the in-control average run length (ARL) performance for different space and time closeness thresholds as well as for different control limit values. The effect of nonuniform population density and region shape on the in-control ARL is explained and some issues that should be considered when implementing this method are also discussed. In the wavelet-based prospective monitoring method, a surface of incidence counts is modeled over time in the geographical region of interest. This surface is modeled using Poisson regression where the regressors are wavelet functions from the Haar wavelet basis. The surface is estimated each time new incidence data is obtained using both past and current observations, weighing current observations more heavily. The flexibility of this method allows for the detection of changes in the incidence surface, increases in the overall mean incidence count, and clusters of disease occurrences within individual areas of the region, through the use of control charts. This method is also able to incorporate information on population size and other covariates as they change in the geographical region over time. The control charts developed for use in this method are evaluated based on their in-control and out-of-control ARL performance and recommendations on the most appropriate control chart to use for different monitoring scenarios is provided.
Ph. D.
9

Moreira, Gladston Juliano Prates. "The detection of spatial clusters: graph and dynamic programming based methods." Universidade Federal de Minas Gerais, 2011. http://hdl.handle.net/1843/BUOS-8MCG9A.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
This thesis addresses the spatial and space-time cluster detection problem. Two algorithms to solve the typical problem for spatial data sets are proposed. A fast method for the detection and inference of point data set spatial and space-time disease clusters is presented, the Voronoi Based Scan (VBScan). A Voronoi diagram is built for points representing population individuals (cases and controls). The number of Voronoi cells boundaries intercepted by the line segment joining two cases points defines the Voronoi distance between those points. This distance is used to approximate the density of the heterogeneous population and build the Voronoi distance Minimum Spanning Tree (VMST) linking the cases. The successive removal of edges from the VMST generates sub-trees which are the potential clusters. Finally, those clusters are evaluated through the scan statistic. Monte Carlo replications of the original data are used to evaluate the significance of the clusters. The ability to promptly detect space-time clusters of disease outbreaks, when the number of individuals is large, was shown to be feasible, due to the reduced computational load of VBScan. Numerical simulations showed that VBScan has higher power of detection, sensitivity and positive predicted value than the Elliptic PST. Furthermore, an application for dengue fever in a small Brazilian city is presented. In a second approach, the typical spatial cluster detection problem is reformulated as a bi-objective combinatorial optimization problem. We propose an exact algorithm based on dynamic programming, Geographical Dynamic Scan, which empirically was able to solve instances up to large size within a reasonable computational time. We show that the set of nonv dominated solutions of the problem, computed efficiently, contains the solution that maximizes the Kulldorffs Spatial Scan Statistic. The method allows arbitrary shaped clusters, which can be a collection of disconnected or connected areas, taking into account a geometric constraint. Note that this is not a serious disadvantage, provided that there is not a huge gap between its component areas. We present an empirical comparison of detection and spatial accuracy between our algorithm and the classical Kulldorffs Circular Scan, using the data set of Chagas disease cases in puerperal women in Minas Gerais state, Brazil.
Esta tese aborda o problema de detecção de clusters espaciais e espaços-temporais. Dois algoritmos para resolver o típico problema de conjuntos de dados com processos espaciais são propostos. Um método eficiente para a detecção e inferência de clusters de doenças espaciais e espaços-temporais de dados pontuais é apresentado, o Voronoi Based Scan (VBScan). Um diagrama de Voronoi é construído para os pontos que representam indivíduos da população (casos e controles). O número de células de Voronoi interceptadas pelo segmento de linha que une de dois pontos que representam dois casos define a distância de Voronoi entre esses pontos. Esta distância é usada para aproximar a densidade da população heterogenia e construir a árvore geradora m·nima baseada na distância de Voronoi (VMST) ligando os casos. A remoção sucessiva de arestas da VMST gera sub-arvores que são os clusters candidatos potenciais. Finalmente, os clusters são avaliados através da estatística scan de Kulldorff. Simulações de Monte Carlo dos dados originais são usados para avaliar a significância dos clusters. A capacidade de detectar rapidamente clusters de surtos da doença, quando o número de indivíduos é grande, mostrou-se viável, devido à redução da carga computacional obtida com o VBScan. As simulações numéricas mostraram que o VBScan tem maior poder de detecção, sensibilidade e valor preditivo positivo do que o scan elíptico. Além disso, uma aplicação de casos e controles georeferenciados de dengue em uma cidade do Brasil é apresentado. Numa segunda abordagem, o problema típico de detecção de clusters espaciais é reformulado como um problema bi-objetivo de otimização combinatória Nós propomos um algoritmo exato baseado em programação dinâmica, Geographical Dynamic Scan, que empiricamente foi capaz de resolver os casos até de grande porte dentro de tempo computacional aceitável. Nós mostramos que o conjunto de soluções não dominadas do problema, encontradas eficientemente, contém a solução que maximiza a estatística scan de Kulldorf. O método permite clusters de formatos arbitrários, que podem ser uma coleção de regiões desconectadas ou conectadas, tendo em conta uma restrição geográfica. Note-se que esta não é uma séria desvantagem, desde que não haja um grande espaçamento entre as suas áreas. Apresentamos uma comparação empírica de detecção e precisão espacial entre o nosso algoritmo e o clássico Scan circular, utilizando dados de casos de doença de Chagas em mulheres parturientes no estado de Minas Gerais, Brasil.
10

Oliveira, Fernando Luiz Pereira de. "Nonparametric intensity bounds for the detection and delineation of spatial clusters." Universidade Federal de Minas Gerais, 2011. http://hdl.handle.net/1843/ICED-8GQJAE.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
There is considerable uncertainty in the disease rate estimation for aggregated area maps, especially for small population areas. As a consequence the delineation of local clustering is subject to substantial variation. Consider the most likely disease cluster produced by any given method, like SaTScan Kulldorff [2006], for the detection and inference of spatial clusters in a map divided into areas; if this cluster is found to be statistically signifcant, what could be said of the external areas adjacent to the cluster? Do we have enough information to exclude them from a health program of prevention? Do all the areas inside the cluster have the same importance from a practitioner perspective? We propose a criterion to measure the plausibility of each area being part of a possible localized anomaly in the map. In this work we assess the problem of finding error bounds for the delineation of spatial clusters in maps of areas with known populations and observed number of cases. A given map with the vector of real data (the number of observed cases for each area) shall be considered as just one of the possible realizations of the random variable vector with an unknown expected number of cases. In our methodology we perform m Monte Carlo replications: we consider that the simulated number of cases for each area is the realization of a random variable with average equal to the observed number of cases of the original map. Then the most likely cluster for each replicated map is detected and the corresponding m likelihood values obtained by means of the m replications are ranked. For each area, we determine the maximum likelihood value obtained among the most likely clusters containing that area. Thus, we construct the intensity function associated to each area's ranking of its respective likelihood value among the m obtained values. The method is tested in numerical simulations and applied for three different real data maps for sharply and diffusely delineated clusters. The intensity bounds found by the method re ect the geographic dispersion of the detected clusters. The proposed technique is able to detect irregularly shaped and multiple clusters, making use of simple tools like the circular scan. Intensity bounds for the delineation of spatial clusters are obtained and indicate the plausibility of each area belonging to the real cluster. This tool employs simple mathematical concepts and interpreting the intensity function is very intuitive in terms of the importance of each area in delineating the possible anomalies of the map of rates. The Monte Carlo simulation requires an effort similar to the circular scan algorithm, and therefore it is quite fast. We hope that this tool should be useful in public health decision making of which areas should be prioritized.
texto completo
Більше джерел

Книги з теми "Clusters detection":

1

Rogerson, Peter. Statistical detection and surveillance of geographic clusters. Boca Raton: Chapman & Hall/CRC, 2009.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Hojjatoleslami, S. A. A system for the detection of clusters of microcalcification in digitized mammograms. [Guildford: Department of Electronic & Electrical Engineering, University of Surrey, 1996.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Pauly, Hans. Atom, molecule, and cluster beams I: Basic theory, production and detection of thermal energy beams. Berlin: Springer Berlin Heidelberg, 2000.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Luttrell, Stephen P. A trainable texture anomaly detector using the adaptive cluster expansion (ACE) method. London: HMSO, 1990.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Vavrik, Ursula. A priori and a posteriori travel market segmentation: Tailoring automatic interaction detection and cluster analysis for tourism marketing. Aix-en-Provence: Centre des Hautes Etudes Touristiques, 1990.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
6

Rogerson, Peter, and Ikuho Yamada. Statistical Detection and Surveillance of Geographic Clusters. Taylor & Francis Group, 2009.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Rogerson, Peter, and Ikuho Yamada. Statistical Detection and Surveillance of Geographic Clusters. Chapman and Hall/CRC, 2008. http://dx.doi.org/10.1201/9781584889366.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Rogerson, Peter, and Ikuho Yamada. Statistical Detection and Surveillance of Geographic Clusters. Taylor & Francis Group, 2008.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Rogerson, Peter, and Ikuho Yamada. Statistical Detection and Surveillance of Geographic Clusters. Taylor & Francis Group, 2008.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Rogerson, Peter, and Ikuho Yamada. Statistical Detection and Monitoring of Geographic Clusters. Chapman & Hall/CRC, 2008.

Знайти повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Більше джерел

Частини книг з теми "Clusters detection":

1

Jaffe, W. J., A. G. Bruyn, and D. Sijbreng. "HI Absorption Detection in the Perseus Cooling Flow." In Cooling Flows in Clusters and Galaxies, 145–47. Dordrecht: Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-2953-1_16.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Duczmal, Luiz H., and André L. F. Cançado. "Irregular Shaped Spatial Clusters: Detection and Inference." In Encyclopedia of GIS, 1–8. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-23519-6_1544-1.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Duczmal, Luiz H., and André L. F. Cançado. "Irregular Shaped Spatial Clusters: Detection and Inference." In Encyclopedia of GIS, 1086–92. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-17885-1_1544.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Manghiuc, Bogdan-Adrian. "Distributed Detection of Clusters of Arbitrary Size." In Structural Information and Communication Complexity, 370–87. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-79527-6_21.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Lignières, J., B. d’Humières, and J. C. Rivoal. "Linear and circular dichroism detection of magnetic torque on matrix isolated small manganese clusters." In Small Particles and Inorganic Clusters, 207–9. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-642-76178-2_50.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
6

McLoughlin, Kristin J., Philip J. Bones, and Peter D. Kovesi. "Detection of Microcalcification Clusters in Digital Mammogram Images." In Digital Mammography, 353–57. Berlin, Heidelberg: Springer Berlin Heidelberg, 2003. http://dx.doi.org/10.1007/978-3-642-59327-7_83.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
7

Zhao, Qinpei, Ville Hautamaki, and Pasi Fränti. "Knee Point Detection in BIC for Detecting the Number of Clusters." In Advanced Concepts for Intelligent Vision Systems, 664–73. Berlin, Heidelberg: Springer Berlin Heidelberg, 2008. http://dx.doi.org/10.1007/978-3-540-88458-3_60.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Andrienko, Natalia, Gennady Andrienko, Georg Fuchs, Salvatore Rinzivillo, and Hans-Dieter Betz. "Real Time Detection and Tracking of Spatial Event Clusters." In Machine Learning and Knowledge Discovery in Databases, 316–19. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-23461-8_38.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Davies, D. H., and D. R. Dance. "Automatic Detection of Clusters of Calcifications in Digital Mammograms." In CAR’89 Computer Assisted Radiology / Computergestützte Radiologie, 180–84. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-52311-3_33.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Kumar, Arun, and Vishal Verma. "Relationships Among Human Genome Graph Elements Using Clusters Detection." In Communications in Computer and Information Science, 151–61. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-09469-9_14.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.

Тези доповідей конференцій з теми "Clusters detection":

1

Schreiber, E., K. Kobe, H. Kühling, S. Rohland, A. Ruff, S. Rutz, G. Sommerer, and L. Wöste. "Ultrafast Spectroscopy of Alkali Clusters." In International Conference on Ultrafast Phenomena. Washington, D.C.: Optica Publishing Group, 1994. http://dx.doi.org/10.1364/up.1994.thb.5.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
The fragmentation and wavepacket propagation dynamics of small neutral potassium and sodium clusters in a supersonic cluster beam were investigated using pico- and femtosecond two photon ionization spectroscopy followed by mass-selective detection.
2

C V, Manjushree, and A. N. Nandakumar. "Malware Detection across Clusters." In 2023 International Conference on Intelligent and Innovative Technologies in Computing, Electrical and Electronics (IITCEE). IEEE, 2023. http://dx.doi.org/10.1109/iitcee57236.2023.10090979.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
3

Murray, Brian, and Lokukaluge P. Perera. "Unsupervised Trajectory Anomaly Detection for Situation Awareness in Maritime Navigation." In ASME 2020 39th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/omae2020-18281.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Abstract Situation awareness is essential in conducting effective collision avoidance in potential ship encounter situations. It has been shown that data driven trajectory prediction techniques, utilizing historical AIS data, have the potential to aid in providing such awareness. However, such data driven techniques will not perform well for unusual ship behavior, i.e. anomalous trajectories. Additionally, such anomalies in the dataset can corrupt the predictions. In this study, an unsupervised approach to anomaly detection is presented to aid such trajectory predictions. Gaussian Mixture Models are used to cluster trajectories, such that clusters of both normal and anomalous trajectories are discovered. Further, anomalies are discovered within clusters of normal behavior. Novel trajectories can then also be evaluated based on a parametric description of the historical ship traffic. The approach is shown to be effective in detecting anomalies relevant in such a trajectory prediction scheme.
4

Mittal, Mamta, V. P. Singh, and Sharma R. K. "Random automatic detection of clusters." In 2011 IEEE International Conference on Image Information Processing (ICIIP). IEEE, 2011. http://dx.doi.org/10.1109/iciip.2011.6108856.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Steadman, J., E. W. Fournier, and J. A. Syage. "Detection and Differentiation of Neutral and Ionic Reaction Mechanisms in Molecular Clusters." In Laser Applications to Chemical Analysis. Washington, D.C.: Optica Publishing Group, 1990. http://dx.doi.org/10.1364/laca.1990.pd4.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
A longstanding goal in the chemical analysis of reaction mechanisms is understanding the role of the solvent. We have been involved in work that addresses this issue on a single molecule basis by studying reactions in molecular clusters.1–3 In this report we describe a means for detecting and measuring rapid intermolecular cluster chemistry using mass-selective picosecond resonance-enhanced multiphoton ionization (REMPI). Molecular beam mass spectrometry offers a powerful means for identifying a variety of product species and distinguishing precursor cluster size. However, such investigations demand an independent means for differentiating neutral cluster reactions from ionic reactions. Our approach is to obtain direct measurements of the ion dissociation mechanisms by electron-impact (El) ionization and by mass-selective ion photodissociation.
6

Cox, D. M., M. R. Zakin, R. O. Brickman, D. J. Trevor, K. C. Reichmann, and A. Kaldor. "Infrared photodissociation spectroscopy of unsupported metal clusters and metal cluster complexes." In International Laser Science Conference. Washington, D.C.: Optica Publishing Group, 1986. http://dx.doi.org/10.1364/ils.1986.fn2.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
The recent development of a general source to produce gas phase metal clusters using laser vaporization combined with mass selective detection techniques has enabled new studies of the fundamental chemical and physical properties of clusters as a function of their size. In our laboratory we have developed and applied a variety of experimental techniques to measure ionization thresholds, magnetic moments, and gas phase reactivities of metal clusters. We now report the first observation of infrared laser-induced dissociation (IR-LID) of metal cluster–adsorbate complexes in a molecular beam. Specifically, using a high-power pulsed CO2 laser as the infrared source, we have measured the IR-LID spectrum for the iron clusters containing chemisorbed methanol as a function of the number of iron atoms for a known number of chemisorbed molecules. For clusters which have chemisorbed only one methanol, strong IR adsorption is observed near 985 and 1075cm−1, adsorptions presently assigned to the C–O stretch of chemisorbed methoxy radical and bridging hydrogen, respectively, i.e., the methanol is dissociatively chemisorbed. Both the feasibility and potential utility of IR-LID for characterizing metal cluster–adsorbate interactions have been demonstrated. The method is generally applicable to any cluster or cluster-adsorbate system dependent only on the availability of appropriate high-power IR laser sources.
7

Cox, D. M., M. R. Zakin, R. O. Brickman, D. J. Trevor, K. C. Reichmann, and A. Kaldor. "Infrared photodissociation spectroscopy of unsupported metal clusters and metal cluster complexes." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1986. http://dx.doi.org/10.1364/oam.1986.fn2.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
The recent development of a general source to produce gas phase metal clusters using laser vaporization combined with mass selective detection techniques has enabled new studies of the fundamental chemical and physical properties of clusters as a function of their size. In our laboratory we have developed and applied a variety of experimental techniques to measure ionization thresholds, magnetic moments, and gas phase reactivities of metal clusters. We now report the first observation of infrared laser-induced dissociation (IR-LID) of metal cluster-adsorbate complexes in a molecular beam. Specifically, using a high-power pulsed CO2 laser as the infrared source, we have measured the IR-LID spectrum for the iron clusters containing chemisorbed methanol as a function of the number of iron atoms for a known number of chemisorbed molecules. For clusters which have chemisorbed only one methanol, strong IR adsorption is observed near 985 and 1075 cm-1, adsorptions presently assigned to the C-O stretch of chemisorbed methoxy radical and bridging hydrogen, respectively, i.e., the methanol is dissociatively chemisorbed. Both the feasibility and potential utility of IR-LID for characterizing metal cluster-adsorbate interactions have been demonstrated. The method is generally applicable to any cluster or cluster-adsorbate system dependent only on the availability of appropriate high-power IR laser sources.
8

Scoles, G. "IR spectroscopy of molecules attached to liquid He clusters." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/oam.1992.mee2.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Helium clusters containing a few thousand monomers, formed from a sonic nozzle at 15 K, are doped with SF6 molecules that they pick up in a scattering box containing this gas at partial pressures of 10−5 to 10−4 Torr. The IR spectrum of the doped clusters is obtained by line tunable CO2 laser excitation of the SF6 and bolometric detection of the photoevaporated helium atoms. If the clusters contain a single SF6 molecule, the spectrum shows two absorptions located at 945.8 cm−1 and 946.1 cm−1, which indicates that the SF6 molecule is located in an anisotropic environment, i.e., near the surface of the cluster. If the cluster contains two SF6 molecules, the spectrum of the SF6 dimer is recovered and found to be very narrow, as appropriate to the very low temperature of the medium in which the spectrum is taken (~0.4 K). The linear and quadratic dependence of the spectral intensities of, respectively, the monomer and the dimer features allows for an independent confirmation of the average cluster size.
9

Pavasant, Nat, Masayuki Numao, and Ken-ichi Fukui. "Spatio-Temporal Change Detection Using Granger Sequence Pattern." In Twenty-Ninth International Joint Conference on Artificial Intelligence and Seventeenth Pacific Rim International Conference on Artificial Intelligence {IJCAI-PRICAI-20}. California: International Joint Conferences on Artificial Intelligence Organization, 2020. http://dx.doi.org/10.24963/ijcai.2020/741.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
This paper proposed a method to detect changes in causal relations over a multi-dimensional sequence of events. Cluster Sequence Mining algorithm was modified to extract causal relations in the form of g-patterns: a pair of clusters of events that have their occurrence time determined by Granger causality. This paper also proposed the pattern time signature, a probabilistic density function of the cluster sequence occurring at any given time. Synthetic data were used for validation. The result shows that the proposed algorithm can correctly identify the changes in causal relations even under noisy data.
10

Desai, Narayan, Rick Bradshaw, and Ewing Lusk. "Disparity: Scalable Anomaly Detection for Clusters." In 2008 International Conference on Parallel Processing Workshops (ICPP-W). IEEE, 2008. http://dx.doi.org/10.1109/icpp-w.2008.30.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.

Звіти організацій з теми "Clusters detection":

1

Lawrence, Kaitlyn, Wendy Kuhne, and Ashlee Swindle. Development of FRET clusters for CBRN Detection. Office of Scientific and Technical Information (OSTI), August 2020. http://dx.doi.org/10.2172/1651109.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
2

Campi, Mercedes, and Marco Dueñas. Clusters and Resilience during the COVID–19 Crisis: Evidence from Colombian Exporting Firms. Inter-American Development Bank, October 2022. http://dx.doi.org/10.18235/0004474.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
In this paper, we characterize the geography of Colombian exporting clusters and analyze how the COVID-19 crisis has affected Colombian exporters. We contribute to the industrial clusters literature by defining exporting clusters with bipartite network analysis and community detection tools. The methodology allows us to empirically detect product clusters, which are compared with an alternative definition of industrial clusters, and to consider the centrality of firms within clusters. Then, we analyze the firms trade margins during the COVID-19 crisis to evaluate whether belonging to an exporting cluster can be a source of resilience for firms. We find that clusters do not automatically lead to higher resilience and that there are differences in how firms react to a crisis within clusters. Identifying the relevant firms characteristics can guide policymakers to activate the mechanisms that generate resilience.
3

Piacentine, J. Detection of Galaxy Clusters with the XMM-Newton Large Scale Structure Survey. Office of Scientific and Technical Information (OSTI), September 2004. http://dx.doi.org/10.2172/833122.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
4

Uy, D. L. An algorithm for image clusters detection and identification based on color for an autonomous mobile robot. Office of Scientific and Technical Information (OSTI), February 1996. http://dx.doi.org/10.2172/184307.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
5

Cytryn, E., Sean F. Brady, and O. Frenkel. Cutting edge culture independent pipeline for detection of novel anti-fungal plant protection compounds in suppressive soils. Israel: United States-Israel Binational Agricultural Research and Development Fund, 2022. http://dx.doi.org/10.32747/2022.8134142.bard.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
Fusarium oxysporum spp. causes Panama disease in bananas and crown and root rot in an array of vegetables and field crops, but increased regulations have restricted the use of many conventional chemical pesticides, and there are a limited number of commercially available products effective against them. The soil microbiome represents a largely untapped reservoir of secondary metabolites that can potentially antagonize fungal pathogens. However, most soil bacteria cannot be cultivated using conventional techniques and therefore most of these compounds remain unexplored. The overall goal of this two-year project was to extract and characterize novel secondary metabolites from "unculturable" soil microbiomes that antagonize Fusarium and other fungal plant pathogens. Initially, the Cytryn lab at the Volcani Institute (ARO) identified candidate biosynthetic gene clusters (BGCs) encoding for potentially novel antifungal compounds (specifically non-ribosomal peptides and polyketides) in soil and plant root microbiomes using cutting-edge metagenomic platforms. Next, the Brady lab at Rockefeller University (RU) screened archived soil metagenomic cosmid libraries for these BGCs, and heterologously expressed them in suitable hosts. Finally, the Frenkel and Cytryn labs at ARO assessed the capacity of these heterologous expressed strains to antagonize Fusarium and other fungal plant pathogens. Initially tomato and lettuce were analyzed, and subsequently roots of cucumbers grown in suppressive (biochar amended) soils were targeted. We found that the composition of tomato and lettuce root BGCs are similar to each other, but significantly different from adjacent bulk soil, indicating that root bacteria possess specific secondary metabolites that are potentially associated with rhizosphere competence. BGC linked to known metabolites included various antimicrobial, (e.g., streptazone E, sessilin), antifungal (heat-stable antifungal factor- HSAF, II and ECO-02301), and insecticidal (melingmycin, orfamide A) compounds. However, over 90% of the identified BGCs were moderately to significantly different from those encoding for characterized secondary metabolites, highlighting the profusion of potentially novel secondary metabolites in both root and soil environments. Novel BGCs that were abundant in roots and remotely resembled those of antifungal compounds were transferred to RU for subsequent screening and five were identified in RU soil metagenomic cosmid libraries. Two of these clusters (BARD-1711 BARD-B481) were heterologously-expressed in a Streptomyces albus J1074 strain, and transferred to ARO. The strain harboring BARAD-B481 was found to antagonize Fusarium significantly more than the host strain, indicating that this BGCs product has antifungal activity. Future studies will need to work on chemically characterizing the BARAD-B481 BGC and progress with the above described pipeline for other interesting BGCs.
6

Kirichek, Galina, Vladyslav Harkusha, Artur Timenko, and Nataliia Kulykovska. System for detecting network anomalies using a hybrid of an uncontrolled and controlled neural network. [б. в.], February 2020. http://dx.doi.org/10.31812/123456789/3743.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
Анотація:
In this article realization method of attacks and anomalies detection with the use of training of ordinary and attacking packages, respectively. The method that was used to teach an attack on is a combination of an uncontrollable and controlled neural network. In an uncontrolled network, attacks are classified in smaller categories, taking into account their features and using the self- organized map. To manage clusters, a neural network based on back-propagation method used. We use PyBrain as the main framework for designing, developing and learning perceptron data. This framework has a sufficient number of solutions and algorithms for training, designing and testing various types of neural networks. Software architecture is presented using a procedural-object approach. Because there is no need to save intermediate result of the program (after learning entire perceptron is stored in the file), all the progress of learning is stored in the normal files on hard disk.
7

Stalley, Sean. Clustered Hyperspectral Target Detection. Portland State University Library, January 2000. http://dx.doi.org/10.15760/etd.7514.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
8

Hao, Jiangang. Optical galaxy cluster detection across a wide redshift range. Office of Scientific and Technical Information (OSTI), April 2009. http://dx.doi.org/10.2172/971005.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
9

Wessel, J. Molecular detection using Rydberg, autoionizing, and cluster states. Progress report. Office of Scientific and Technical Information (OSTI), August 1990. http://dx.doi.org/10.2172/674621.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.
10

Wessel, J. Molecular detection using Rydberg, autoionizing, and cluster states. Progress report. Office of Scientific and Technical Information (OSTI), August 1989. http://dx.doi.org/10.2172/674622.

Повний текст джерела
Стилі APA, Harvard, Vancouver, ISO та ін.

До бібліографії