594 research outputs found
The What-And-Where Filter: A Spatial Mapping Neural Network for Object Recognition and Image Understanding
The What-and-Where filter forms part of a neural network architecture for spatial mapping, object recognition, and image understanding. The Where fllter responds to an image figure that has been separated from its background. It generates a spatial map whose cell activations simultaneously represent the position, orientation, ancl size of all tbe figures in a scene (where they are). This spatial map may he used to direct spatially localized attention to these image features. A multiscale array of oriented detectors, followed by competitve and interpolative interactions between position, orientation, and size scales, is used to define the Where filter. This analysis discloses several issues that need to be dealt with by a spatial mapping system that is based upon oriented filters, such as the role of cliff filters with and without normalization, the double peak problem of maximum orientation across size scale, and the different self-similar interpolation properties across orientation than across size scale. Several computationally efficient Where filters are proposed. The Where filter rnay be used for parallel transformation of multiple image figures into invariant representations that are insensitive to the figures' original position, orientation, and size. These invariant figural representations form part of a system devoted to attentive object learning and recognition (what it is). Unlike some alternative models where serial search for a target occurs, a What and Where representation can he used to rapidly search in parallel for a desired target in a scene. Such a representation can also be used to learn multidimensional representations of objects and their spatial relationships for purposes of image understanding. The What-and-Where filter is inspired by neurobiological data showing that a Where processing stream in the cerebral cortex is used for attentive spatial localization and orientation, whereas a What processing stream is used for attentive object learning and recognition.Advanced Research Projects Agency (ONR-N00014-92-J-4015, AFOSR 90-0083); British Petroleum (89-A-1204); National Science Foundation (IRI-90-00530, Graduate Fellowship); Office of Naval Research (N00014-91-J-4100, N00014-95-1-0409, N00014-95-1-0657); Air Force Office of Scientific Research (F49620-92-J-0499, F49620-92-J-0334
A What-and-Where Neural Network for Invariant Image Preprocessing
A feedforward neural network for invariant image preprocessing is proposed that represents the position1 orientation and size of an image figure (where it is) in a multiplexed spatial map. This map is used to generate an invariant representation of the figure that is insensitive to position1 orientation, and size for purposes of pattern recognition (what it is). A multiscale array of oriented filters followed by competition between orientations and scales is used to define the Where filter.British Petroleum (89-A-1024); Defense Advanced Research Projects Agency (90-0083); National Science Foundation (IRI 90-00530); Office of Naval Research (N0014-91-J-4100); Air Force Office of Scientific Research (90-0175); NSF Graduate Fellowshi
Fusion Artmap: A Neural Network Architecture for Multi-Channel Data Fusion and Classification
Fusion ARTMAP is a self-organizing neural network architecture for multi-channel, or multi-sensor, data fusion. Single-channel Fusion ARTMAP is functionally equivalent to Fuzzy ART during unsupervised learning and to Fuzzy ARTMAP during supervised learning. The network has a symmetric organization such that each channel can be dynamically configured to serve as either a data input or a teaching input to the system. An ART module forms a compressed recognition code within each channel. These codes, in turn, become inputs to a single ART system that organizes the global recognition code. When a predictive error occurs, a process called paraellel match tracking simultaneously raises vigilances in multiple ART modules until reset is triggered in one of them. Parallel match tracking hereby resets only that portion of the recognition code with the poorest match, or minimum predictive confidence. This internally controlled selective reset process is a type of credit assignment that creates a parsimoniously connected learned network. Fusion ARTMAP's multi-channel coding is illustrated by simulations of the Quadruped Mammal database.Defense Advanced Research Projects Agency (ONR N0014-92-J-401J, AFOSR 90-0083, ONR N00014-92-J-4015); National Science Foundation (IRI-90-00530, IRI-90-24877, Graduate Fellowship); Office of Naval Research (N00014-91-J-4100); British Petroleum (89-A-1204); Air Force Office of Scientific Research (F49620-92-J-0334
Fusion ARTMAP: An Adaptive Fuzzy Network for Multi-Channel Classification
Fusion ARTMAP is a self-organizing neural network architecture for multi-channel, or multi-sensor, data fusion. Fusion ARTMAP generalizes the fuzzy ARTMAP architecture in order to adaptively classify multi-channel data. The network has a symmetric organization such that each channel can be dynamically configured to serve as either a data input or a teaching input to the system. An ART module forms a compressed recognition code within each channel. These codes, in turn, beco1ne inputs to a single ART system that organizes the global recognition code. When a predictive error occurs, a process called parallel match tracking simultaneously raises vigilances in multiple ART modules until reset is triggered in one of thmn. Parallel match tracking hereby resets only that portion of the recognition code with the poorest match, or minimum predictive confidence. This internally controlled selective reset process is a type of credit assignment that creates a parsimoniously connected learned network.Advanced Research Projects Agency (ONR N00014-92-J-401J, ONR N00014-92-J-4015); National Science Foundation (IRI-90-00530, IRI-90-24877, Graduate Fellowship); Office of Naval Research (N00014-91-J-4100); British Petroleum (89-A-1204); Air Force Office of Scientific Research (F49620-92-J-0334
Immunologic Status of Uremic Patients
The immunologic status of 25 uremic patients was studied with a battery of tests evaluating the humoral and cytological aspects of immunity. The individual\u27s humoral immune status was evaluated as follows: quantitation of the three major serum immunoglobulins (IgG, IgA and IgM) expressed in mg/100 ml of serum and compared to established normal clinical standards (±2 SD/mean); qualitation of IgG and IgM evaluated by specific virus antibody titers and antitoxin values associated with IgG and by isoagglutinin tilers of the ABO blood groups associated with IgM. Immunoglobulin status is grouped into hyper- and hypo-immunoglobulin variations from normal and correlated with serum complement values (Beta 1C/1A and hemolytic activity). The cytological status in the evaluation consists of assaying the individual\u27s ability to produce interferon by the Sendai-Sindbis virus system in peripheral blood leukocytes. Results of the study emphasize the need for individual evaluation of uremic patients to enable more effective immuno- depressive therapy before and after renal transplantation
Preparation of a ZrO₂-Al₂O₃ Nanocomposite by High-Pressure Sintering of Spray-Pyrolyzed Powders
ZrO2-Al2O3 powders were synthesized by spray pyrolysis. These powders were sintered at 1 GPa in the temperature range of 700Ç1100 ÉC. The microstructural evolution and densification are reported in this paper. The application of 1 GPa pressure lowers the crystallization temperature from ~850 to 700 ÉC. Similarly, the transformation temperature under 1 GPa pressure for \u3c\u3eg ê a Al2O3 reduces from ~1100 to 700Ç800 ÉC range, and that for t \u3c\u3eê m ZrO2 reduces from ~1050 to 700Ç800 ÉC range. It was possible to ob-tain highly-dense nanocrystalline ZrO2-Al2O3 composite at temperatures as low as 700 ÉC. The effect of high pressure on nucleation and transformation of phases is discussed
Identification of mixed-symmetry states in an odd-mass nearly-spherical nucleus
The low-spin structure of 93Nb has been studied using the (n,n' gamma)
reaction at neutron energies ranging from 1.5 to 3.0 MeV and the 94Zr(p,2n
gamma)93Nb reaction at bombarding energies from 11.5 to 19 MeV. States at
1779.7 and 1840.6 keV, respectively, are proposed as mixed-symmetry states
associated with the coupling of a proton hole in the p_1/2 orbit to the 2+_1,ms
state in 94Mo. These assignments are derived from the observed M1 and E2
transition strengths to the symmetric one-phonon states, energy systematics,
spins and parities, and comparison with shell model calculations.Comment: 5 pages, 3 figure
Característica de la preparación del personal para la gestión de conflictos en la organización
The analysis of the personnel competence, reflected in the professional standards, allows us to identify the main areas of training that have a positive impact on the challenges of the external environment. At the same time, employees of the organization, as a rule, have different professional training and practical experience. From this perspective, the phenomenon of in-house training of the personnel is updated, under which the training is carried out on the basis of the organization and aimed at achieving the objectives to develop it. Communication, as a mechanism of using communicative skills that can have both positive and negative effects, occupies a leading position in the professional activities of the personnel. Thus, it is connected, in most cases, with conflicts, in particular, the lack of personnel preparedness and readiness to manage them. Researchers are actively engaged in finding the ways to prevent and resolve conflicts, using various forms of post-graduate training, including in-house training of adult audience.El análisis de la competencia del personal, reflejado en los estándares profesionales, nos permite identificar las principales áreas de capacitación que tienen un impacto positivo en los desafíos del entorno externo. Al mismo tiempo, los empleados de la organización, por regla general, tienen diferente formación profesional y experiencia práctica. Desde esta perspectiva, se actualiza el fenómeno de la capacitación interna del personal, en virtud del cual la capacitación se lleva a cabo sobre la base de la organización y dirigida a lograr los objetivos para desarrollarla. La comunicación, como mecanismo para utilizar habilidades comunicativas que pueden tener efectos tanto positivos como negativos, ocupa una posición de liderazgo en las actividades profesionales del personal. Por lo tanto, está relacionado, en la mayoría de los casos, con conflictos, en particular, la falta de preparación y preparación del personal para manejarlos. Los investigadores participan activamente en la búsqueda de formas de prevenir y resolver conflictos, utilizando diversas formas de capacitación de posgrado, incluida la capacitación interna de la audiencia adulta
Comparación de tres métodos para la extracción de ARN total a partir de hojas de cacao
The establishment of a method for extracting total RNA in plants that meets the required criteria of purity and yield is a critical step for subsequent molecular studies, especially in recalcitrant plants with naturally high amounts of polyphenols, polysaccharides and proteins. These have been referred to as the main contaminants in extraction methods. In this study the efficiency of three methods of RNA extraction from cacao leaves (Theobroma cacao L.) for later use in molecular analyzes were compared. Established protocols were followed and assessed the quantity and quality of RNA obtained. It was possible to reproduce the three methods, but differences were found regarding the development time and quality of RNA obtained. The best method for extraction of total RNA was TRI- Reagent, which allowed obtaining RNA with the characteristics of quality and concentration necessaries for future studies, in addition to ease of use and the number of samples that can be assayed. Keywords: method, laboratory, polyphenols.El establecimiento de un método de extracción de ARN total de plantas que cumpla con los criterios requeridos de pureza y rendimiento, es un paso crítico para estudios moleculares posteriores, sobre todo en plantas que son recalcitrantes y poseen de manera natural una alta cantidad de polifenoles, polisacáridos y proteínas. Estos se han referido como los principales contaminantes en los métodos de extracción. En este trabajo se compara la eficiencia de tres métodos de extracción de ARN de hojas de cacao (Theobroma cacao L.) para emplearse posteriormente en análisis moleculares. Se siguieron los protocolos establecidos y evaluó la cantidad y calidad del ARN obtenido. Fue posible reproducir los tres métodos, aunque se constataron diferencias respecto al tiempo de desarrollo y la calidad del ARN. El mejor método para la extracción de ARN total fue el de TRI-Reagent, el cual permitió obtener ARN con las características de calidad y concentración necesarias para futuros estudios, además de la facilidad de su empleo y el número de muestras que pueden ser ensayadas. Palabras clave: laboratorios, polifenoles, protocolo
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