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This paper presents a method based on the support vector regression (SVR) model and grey wolf optimizer (GWO) algorithm to efficiently predict the monostatic radar cross-section (mono-RCS) of complex objects over a wide angular range and frequency band. Using only a small-size of the mono-RCS data as the training set to construct the SVR model, the proposed method can predict accurate mono-RCS of complex objects under arbitrary incident angle over the entire three-dimensional space. In addition, the wideband prediction capability of the method is significantly enhanced by incorporating the meta-heuristic algorithm GWO. Numerical experiments verify the efficiency and accuracy of the proposed SVR-GWO model over a wide frequency band [ABSTRACT FROM AUTHOR]

Copyright of Radio Electronics, Computer Science, Control is the property of Zaporizhzhia National Technical University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the design of complex objects, modular principles are of great interest. That approach has both negative and positive consequences. It clearly affects the cost of acquiring the required stock of equipment and, in particular, the spare parts necessary for its maintenance. Optimization of the modular structure of industrial equipment may best be approached in economic terms. Smart information systems for the support of management decisions prove very useful. A structure is proposed for such a system. Examples of such optimization in the aviation industry are presented, and practical experience is noted. [ABSTRACT FROM AUTHOR]

Data correlation evaluation is the basis for data analysis, and the academic community has proposed many indicators to evaluate it, such as the Euclidean distance, and angle cosine, and so on. However, it is diffi- cult for these indicators to effectively express the correlation degree of complex objects. Using traffic intersections as an example, this article proposes an effective method to evaluate the correlation between complex objects. First, based on a large quantity of basic data, a standard data format describing traffic intersection attributes was proposed. Then, experienced engineers were asked to grade the correlation between intersections. Finally, the two intersection standard format datasets were used as model inputs, the engineer correlation rating as the output of the model, and the support vector machine model was employed for training. The results of this data experiment demonstrate that the trained model can effectively express the correlation degree between traffic intersections, and therefore proves the validity of the method. [ABSTRACT FROM AUTHOR]

In the description of complex objects, we need methods which could reflect the complex interconnections between components and sift out if possible those of them which are substantial for the specific application. It is offered in this publication the pattern recognition methods should be used as a unified method for processing of data from complex objects. The proposed algorithm may be used in the recognition of the condition of objects of various nature. The indicated examples prove the practical applicability of the methodology as they represent the solution of specific practical problems.

Copyright of Electronics & Control Systems is the property of National Aviation University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The neural bases of haptically-guided grasp planning and execution are largely unknown, especially for stimuli having no visual representations. Therefore, we used functional magnetic resonance imaging (fMRI) to monitor brain activity during haptic exploration of novel 3D complex objects, subsequent grasp planning, and the execution of the pre-planned grasps. Haptic object exploration, involving extraction of shape, orientation and length of the to-be-grasped targets, was associated with the fronto-parietal, temporo-occipital, and insular cortex activity. Yet, only the anterior divisions of the posterior parietal cortex (PPC) of the right hemisphere were significantly more engaged in exploration of complex objects (vs. simple control disks). None of these regions were re-recruited during the planning phase. Even more surprisingly, the left-hemisphere intraparietal, temporal, and occipital areas that were significantly invoked for grasp planning did not show sensitivity to object features. Finally, grasp execution, involving the re-recruitment of the critical right-hemisphere PPC clusters, was also significantly associated with two kinds of bilateral parieto-frontal processes. The first represents transformations of grasp-relevant target features and is linked to the dorso-dorsal (lateral and medial) parieto-frontal networks. The second monitors grasp kinematics and belongs to the ventro-dorsal networks. Indeed, signal modulations associated with these distinct functions follow dorso-ventral gradients, with left aIPS showing significant sensitivity to both target features and the characteristics of the required grasp. Thus, our results from the haptic domain are consistent with the notion that the parietal processing for action guidance reflects primarily transformations from object-related to effector-related coding, and these mechanisms are rather independent of sensory input modality.

In this paper, an efficient three-dimensional finite-element method (FEM) is introduced to study the scattering from complex three-dimensional objects in the layered media. The proposed method is valid to targets which are located either close to or far away from the media interface. Furthermore, the interface can be either a planar or rough surface in the computational domain. To improve efficiency, the preconditioned conjugate gradient method for normal equations (CGN) are proposed to solve the FEM linear system. Numerical examples are presented to demonstrate the accuracy and efficiency of the presented method. [ABSTRACT FROM AUTHOR]

O artigo aborda a discussão sobre epistemologia ambiental e teoria social, considerando o conflito entre os modelos tradicionais de ciência e os atuais, em transição. O conflito da modernidade tecno-científica se expressa também pela imposição de padrões hegemônicos na produção de conhecimento e pelos estilos de vida decorrentes desses padrões. O principal desafio para viabilizar um novo diálogo de saberes é inserir esse debate no interior de um pensamento complexo em construção, que exige novos olhares e práticas epistemológicas, filosóficas e políticas.This paper focuses on the contemporary debate between epistemological conditions of knowledge and social and cultural understanding of these conditions, considering the mutual influences given by the historical context in which both occur. First of all, the traditional view of science is supported by the disciplinary system that reinforces the fragmented conception about social and natural things or ideas; on the other hand, we observe a strong opposition against that former standpoint from supporters of a new philosophical, political and epistemological vision about social and environmental issues, attached to a thought of complexity.

Background: The StructureMorph project rests on the premise that future publishing platforms will converge multiple applications, such as geographic information systems (GIS) and game engines, and multiple paradigms of computing, such as desktop computing and high-performance computing. Convergent platforms will also present design challenges for scholars. Analysis: In this contribution, one response to these challenges is presented: the Complex Object. Complex Objects are 4D models that alter their shape and surface appearance in response to user interaction, and changes in world time. They also to mimic the behaviours of 2D polygons as configured in geographic information systems, graphically linking attribute data with spatial locales. Conclusion and implications: This article discusses the concept of the Complex Object and describes the software and workflow devised to support its creation. [ABSTRACT FROM AUTHOR]

The neural bases of haptically-guided grasp planning and execution are largely unknown, especially for stimuli having no visual representations. Therefore, we used functional magnetic resonance imaging (fMRI) to monitor brain activity during haptic exploration of novel 3D complex objects, subsequent grasp planning, and the execution of the pre-planned grasps. Haptic object exploration, involving extraction of shape, orientation, and length of the to-be-grasped targets, was associated with the fronto-parietal, temporo-occipital, and insular cortex activity. Yet, only the anterior divisions of the posterior parietal cortex (PPC) of the right hemisphere were significantly more engaged in exploration of complex objects (vs. simple control disks). None of these regions were re-recruited during the planning phase. Even more surprisingly, the left-hemisphere intraparietal, temporal, and occipital areas that were significantly invoked for grasp planning did not show sensitivity to object features. Finally, grasp execution, involving the re-recruitment of the critical right-hemisphere PPC clusters, was also significantly associated with two kinds of bilateral parieto-frontal processes. The first represents transformations of grasp-relevant target features and is linked to the dorso-dorsal (lateral and medial) parieto-frontal networks. The second monitors grasp kinematics and belongs to the ventro-dorsal networks. Indeed, signal modulations associated with these distinct functions follow dorso-ventral gradients, with left aIPS showing significant sensitivity to both target features and the characteristics of the required grasp. Thus, our results from the haptic domain are consistent with the notion that the parietal processing for action guidance reflects primarily transformations from object-related to effector-related coding, and these mechanisms are rather independent of sensory input modality. [ABSTRACT FROM AUTHOR]

Making sense of complex objects is difficult, and typically requires the use of external representations to support cognitive demands while reasoning about the objects. Visualizations are one type of external representation that can be used to support sensemaking activities. In this paper, we investigate the role of two design strategies in making the interactive features of visualizations more supportive of users’ exploratory needs when trying to make sense of complex objects. These two strategies are visibility and complementarity of interactions. We employ a theoretical framework concerned with human–information interaction and complex cognitive activities to inform, contextualize, and interpret the effects of the design strategies. The two strategies are incorporated in the design of Polyvise, a visualization tool that supports making sense of complex four-dimensional geometric objects. A mixed-methods study was conducted to evaluate the design strategies and the overall usability of Polyvise. We report the findings of the study, discuss some implications for the design of visualization tools that support sensemaking of complex objects, and propose five design guidelines. We anticipate that our results are transferrable to other contexts, and that these two design strategies can be used broadly in visualization tools intended to support activities with complex objects and information spaces.

Structured-light (SL) techniques are emerging as popular noncontact approaches for obtaining threedimensional (3-D) measurements of complex objects for real-time applications in manufacturing, bioengineering, and robotics. The performance of SL systems is determined by the emitting (i.e., projector) and capturing (i.e., camera) hardware components and the triangulation configuration between them and an object of interest. A generic design methodology is presented to determine optimal triangulation configurations for SL systems. These optimal configurations are determined with respect to a set of performance metrics: (1) minimizing the 3-D reconstruction errors, (2) maximizing the pixel-to-pixel correspondence between the projector and camera, and (3) maximizing the dispersion of the measured 3-D points within a measurement volume, while satisfying design constraints based on hardware and user-defined specifications. The proposed methodology utilizes a 3-D geometric triangulation model based on ray-tracing geometry and pin-hole models for the projector and camera. Using the methodology, a set of optimal system configurations can be determined for a given set of hardware components. The design methodology was applied to a real-time SL system for surface profiling of complex objects. Experiments were conducted with an optimal sensor configuration and its performance verified with respect to a nonoptimal hardware configuration. [ABSTRACT FROM AUTHOR]

This essay attempts to establish that there are two very different notions of “foundation” at work in Husserl’s Logical Investigation. In the Third Investigation where the term is formally introduced, Husserl is using what I call an « ontological model » that investigates what kinds of contents can exist on their own (independently) and what kinds can exist only as a moment of something else (dependently). According to this model, the concrete has priority over the abstract that is founded upon it. In the Sixth Logical Investigation, by contrast, Husserl orients himself primarily on an « epistemological model » that see the complex as founded upon the relatively simple because they higher-order experiences, e.g. the perceptions of more complex kinds of objects are “founded in” although not reducible to the simpler experiences on which they are founded. The primary example here is that of categorical intuitions that are founded upon, but not reducible to sense intuitions. Distinguishing these two different senses of the term can help us understand better many controversial Husserlian claims, for instance about the way that the experience of the human being as a whole is founded upon the experience of a physical body, even though the entity we encounter includes both bodily and spiritual aspects that are both essentially viewed as moments of the human person who is the object of our experience

We sketch a general theory of complex objects and their constituents. [ABSTRACT FROM AUTHOR]

Abstract: We introduce a novel solid modeling framework taking advantage of the architecture of parallel computing on modern graphics hardware. Solid models in this framework are represented by an extension of the ray representation — Layered Depth-Normal Images (LDNI), which inherits the good properties of Boolean simplicity, localization and domain decoupling. The defect of ray representation in computational intensity has been overcome by the newly developed parallel algorithms running on the graphics hardware equipped with Graphics Processing Unit (GPU). The LDNI for a solid model whose boundary is represented by a closed polygonal mesh can be generated efficiently with the help of hardware accelerated sampling. The parallel algorithm for computing Boolean operations on two LDNI solids runs well on modern graphics hardware. A parallel algorithm is also introduced in this paper to convert LDNI solids to sharp-feature preserved polygonal mesh surfaces, which can be used in downstream applications (e.g., finite element analysis). Different from those GPU-based techniques for rendering CSG-tree of solid models Hable and Rossignac (2007, 2005) , we compute and store the shape of objects in solid modeling completely on graphics hardware. This greatly eliminates the communication bottleneck between the graphics memory and the main memory. [Copyright &y& Elsevier]

Ortho-photo is one of the most important photogrammetric products for archaeological documentation. It consists of a powerful textured representation combining geometric accuracy with rich detail, such as areas of damage and decay. Archaeological applications are usually faced with complex object shapes. Compared with conventional algorithms, ortho-projection of such rough curved objects is still a problem, due to the complex description of the analytical shape of the object. Even using a detailed digital surface model, typical ortho-rectification software does not produce the desired outcome, being incapable of handling image visibility and model occlusions, since it is limited to 2.5-dimensional surface descriptions. This paper presents an approach for the automated production of true ortho-mosaics for the documentation of cultural objects. The algorithm uses precise three-dimensional surface representations derived from laser scanning and several digital images that entirely cover the object of interest. After identifying all model surface triangles in the viewing direction, the triangles are projected back on to all initial images to establish visibilities for every available image. Missing image information can be filled in from adjacent images that must have been subjected to the same true ortho-photo procedure. [ABSTRACT FROM AUTHOR]

XML query languages need to provide some mechanism to inspect and manipulate nodes at all levels of an input tree. We investigate the expressive power provided in this regard by structural recursion. In particular, we show that the combination of vertical recursion down a tree combined with horizontal recursion across a list of trees gives rise to a robust class of transformations: it captures the class of all primitive recursive queries. Since queries are expected to be computable in at most polynomial time for all practical purposes, we next identify a restriction of structural recursion that captures the polynomial time queries. We also give corresponding results for list-based complex objects. [ABSTRACT FROM AUTHOR]

To date, most of the focus regarding digital preservation has been on replicating copies of the resources to be preserved from the “living web” and placing them in an archive for controlled curation. Once inside an archive, the resources are subject to careful processes of refreshing (making additional copies to new media) and migrating (conversion to new formats and applications). For small numbers of resources of known value, this is a practical and worthwhile approach to digital preservation. However, due to the infrastructure costs (storage, networks, machines) and more importantly the human management costs, this approach is unsuitable for web scale preservation. The result is that difficult decisions need to be made as to what is saved and what is not saved. We provide an overview of our ongoing research projects that focus on using the “web infrastructure” to provide preservation capabilities for web pages and examine the overlap these approaches have with the field of information retrieval. The common characteristic of the projects is they creatively employ the web infrastructure to provide shallow but broad preservation capability for all web pages. These approaches are not intended to replace conventional archiving approaches, but rather they focus on providing at least some form of archival capability for the mass of web pages that may prove to have value in the future. We characterize the preservation approaches by the level of effort required by the web administrator: web sites are reconstructed from the caches of search engines (“lazy preservation”); lexical signatures are used to find the same or similar pages elsewhere on the web (“just-in-time preservation”); resources are pushed to other sites using NNTP newsgroups and SMTP email attachments (“shared infrastructure preservation”); and an Apache module is used to provide OAI-PMH access to MPEG-21 DIDL representations of web pages (“web server enhanced preservation”). [ABSTRACT FROM AUTHOR]

Abstract: The well-definedness problem for a programming language consists of checking, given an expression and an input type, whether the semantics of the expression is defined for all inputs adhering to the input type. A related problem is the semantic type-checking problem which consists of checking, given an expression, an input type, and an output type whether the expression always returns outputs adhering to the output type on inputs adhering to the input type. Both problems are undecidable for general-purpose programming languages. In this paper we study these problems for the Nested Relational Calculus, a specific-purpose database query language. We also investigate how these problems behave in the presence of programming language features such as singleton coercion and type tests. [Copyright &y& Elsevier]

A three-dimensional "full-polarized" model for arbitrary transmitter, receiver and target motions in bistatic synthetic aperture radar configurations is proposed. Qualitative validation of this model is presented through comparison with existing results and quantitative validation is obtained from proposed general analytical resolution equations. To take into account complex targets, geometric theory of diffraction based models are considered. Some numerical results are proposed in bistatic and monostatic configurations which permit to check the performance of the proposed model and to highlight the interest of the bistatic synthetic aperture radar imaging. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we propose a schema version model which allows to restructure complex object hierarchy in object-oriented databases. This model extends a schema version model, called RiBS, which is based on the concept of Rich Base Schema. In the RiBS model, each schema version is in the form of updatable class hierarchy view over one base schema, called the RiBS layer, which has richer schema information than any existing schema version in the database. In this paper, we introduce new operations for restructuring composite object hierarchy in schema versions, and explain their semantics. We also touch upon the ways to transform queries posed against a restructured composite object hierarchy into one against the base schema. In addition, we identify several types of conflicts during schema version merging which result from the restructuring operations, and provide a semi-automatic algorithm to resolve the conflicts. The originality of this paper lies in that (1) we introduce several new operations to restructure composite object hierarchy, and (2) this extended RiBS model operations raise the concept of data independence in OODBs upto the schema level. [Copyright &y& Elsevier]

Databases are getting more and more important for storing complex objects from scientific, engineering, or multimedia applications. Examples for such data are chemical compounds, CAD drawings, or XML data. The efficient search for similar objects in such databases is a key feature. However, the general problem of many similarity measures for complex objects is their computational complexity, which makes them unusable for large databases. In this paper, we combine and extend the two techniques of metric index structures and multi-step query processing to improve the performance of range query processing. The efficiency of our methods is demonstrated in extensive experiments on real-world data including graphs, trees, and vector sets. [ABSTRACT FROM AUTHOR]