Mapping-based Approach Research Articles

A mapping-based approach to eliminating self-intersection of offset paths on mesh surfaces for CNC machining

Geometrically, a tool path can be generated by successively offsetting its adjacent path on the surface with a given path interval, which preferably starts from one of the surface boundaries or a primary curve. The key issues involved in offset path planning are the generation of raw offset paths and the elimination of the self-intersection of raw offset paths. Most researches available in this area are focused on how to generate the raw offset paths, however, the latter, especially how to eliminate the self-intersection of the offset paths on mesh surfaces, has not been sufficiently addressed. In this paper, a mapping-based approach to eliminating the self-intersection of offset paths is proposed for the CNC machining of mesh surfaces. The method first flattens the mesh surface onto a predefined plane by using a mesh mapping technique, and then taking the mapping as a guide, the offset paths are also naturally mapped onto the plane, from which those invalid self-intersection loops can be effectively identified and eliminated. To handle the issue of self-intersection for all types of offset path, a notion of local loop is introduced to detect and eliminate the invalid self-intersection loops. After that the planar paths are inversely mapped into the physical space and the final tool paths used for the machining of mesh surface are obtained. Meanwhile, in order to improve the kinematic and dynamic performance of the machine tool when machining along the generated offset paths, a method for rounding the sharp corners of tool paths, which result from the process of eliminating the self-intersection of raw offset paths, is also preliminarily investigated. Finally, the proposed method is validated by the results of simulations and machining experiments.

A Systematic Review of Mapping Strategies for the Sonification of Physical Quantities

The field of sonification has progressed greatly over the past twenty years and currently constitutes an established area of research. This article aims at exploiting and organizing the knowledge accumulated in previous experimental studies to build a foundation for future sonification works. A systematic review of these studies may reveal trends in sonification design, and therefore support the development of design guidelines. To this end, we have reviewed and analyzed 179 scientific publications related to sonification of physical quantities. Using a bottom-up approach, we set up a list of conceptual dimensions belonging to both physical and auditory domains. Mappings used in the reviewed works were identified, forming a database of 495 entries. Frequency of use was analyzed among these conceptual dimensions as well as higher-level categories. Results confirm two hypotheses formulated in a preliminary study: pitch is by far the most used auditory dimension in sonification applications, and spatial auditory dimensions are almost exclusively used to sonify kinematic quantities. To detect successful as well as unsuccessful sonification strategies, assessment of mapping efficiency conducted in the reviewed works was considered. Results show that a proper evaluation of sonification mappings is performed only in a marginal proportion of publications. Additional aspects of the publication database were investigated: historical distribution of sonification works is presented, projects are classified according to their primary function, and the sonic material used in the auditory display is discussed. Finally, a mapping-based approach for characterizing sonification is proposed.

Resting metabolic connectivity in Alzheimer’s disease

Metabolic connectivity analysis of resting 18F-FDG PET is based on the assumption that brain regions whose metabolism is significantly correlated at rest are functionally associated and that the strength of the association is proportional to the magnitude of the correlation coefficient. Therefore, this method could be used to evaluate connectivity networks independently on the basis of performance in specific tasks. Published studies have provided evidence that metabolic connectivity substantially overlaps underlying anatomical pathways and depends on the location of the analyzed regions, but is not influenced by their size. The present review focuses on the methods and meaning of resting inter-regional correlation analysis of cerebral metabolic rate of glucose consumption in Alzheimer’s disease. Accordingly, we describe the evolution of analytical tools from the correlation with a single region of interest to a voxel-based statistical parametric mapping-based approach. We also discuss the pathophysiological implications of metabolic connectivity studies both for Alzheimer-related disconnection syndrome and for default-mode network impairment and compensation mechanisms.

Recognizing hierarchically related biomedical entities using MeSH-based mapping

Identifying hierarchically related entities is a critical step towards constructing bio-networks in the field of biomedical text mining. To this end, we adopt a mapping-based approach by first mapping bio-entities to terms in an established ontology Medical Subject Headings (MeSH). We then utilize the hierarchical relationships available in MeSH to recognize hierarchically related entities. Specifically, we present two approaches to map biomedical entities identified using the Unified Medical Language System (UMLS) Metathesaurus to MeSH terms. The first approach utilizes a special feature provided by the MetaMap algorithm, whereas the other employs approximate phrase-based match to directly map entities to MeSH terms. These two approaches deliver comparable results with an accuracy of 72% and 75%, respectively, based on two evaluation datasets. A thorough error analysis demonstrates that these two approaches result in only around 10% mutual errors, indicating the complementary nature of these two approaches.

Magnetic material identification of a switched reluctance motor

The identification of the magnetic material characteristics for the switched reluctance motor by solving an inverse problem is presented. The inverse problem aims at identifying the magnetic material parameter values of the magnetic circuit, starting from measured torque profiles. The computational time of the inverse problem is appreciably reduced by implementing a space mapping-based inverse approach. Using the space mapping technique, we combine the computationally intensive finite elementmodel with amuch faster magnetic network model. The proposed approach is very helpful for thematerial identification problem on the electrical machine, and the obtained results reveal the success and the reliability of the proposed scheme.

Conformal Mapping-Based Approach for Transformation of Vehicle Loads

For complex pavements, there are circular, elliptic and rectangular shape vehicle loads under different conditions. Treatment way of vehicle loads is studied with conformal mapping method in this paper. Approach for transformation them to uniform circular shape is also researched. Terminal goal is enable the road engineers to accommodate changes of vehicle loads in their used way to pavement design which using static loads with uniform vertical pressure distribution without any more attached difficult.

Genetic map-based location of the red clover (Trifolium pratense L.) gametophytic self-incompatibility locus

Red clover is a hermaphroditic allogamous diploid (2n = 2x = 14) with a homomorphic gametophytic self-incompatibility (GSI) system (Trifolium pratense L.). Red clover GSI has long been studied, and it is thought that the genetic control of GSI constitutes a single locus. Although GSI genes have been identified in other species, the genomic location of the red clover GSI-locus remains unknown. The objective of this study was to use a mapping-based approach to identify simple sequence repeats (SSR) that were closely linked to the GSI-locus. Previously published SSR markers were used in this effort (Sato et al. in DNA Res 12:301-364, 2005). A bi-parental cross was initiated in which the parents were known to have one self-incompatibility allele (S-allele) in common. S-allele genotypes of 100 progeny were determined through test crosses and pollen compatibility. Pseudo F(1) linkage analysis isolated the GSI-locus on red clover linkage-group one within 2.5 cM of markers RCS5615, RCS0810, and RCS3161. A second 256 progeny mapping testcross population of a heterozygous self-compatible mutant revealed that this specific self-compatible mutant mapped to the same location as the GSI-locus. Finally, 82 genotypes were identified whose parents putatively shared one S-allele in common from maternal halfsib families derived from two random mating populations in which paternal identity was determined using molecular markers. Unique S-allele identity in the two random mating populations was tentatively inferred based on haplotypes of two highly allelic linkage-group one SSR (RCS0810 and RCS4956), which were closely linked to each other and the GSI-locus. Paternally derived pollen haplotype linkage analysis of RCS0810 and RCS4956 SSR and the GSI-locus again revealed tight linkage at 2.5 and 4.7 cM between the GSI-locus and RCS0810 and RCS4956, respectively. The map-based location of the GSI-locus in red clover has many immediate applications to red clover plant breeding and could be useful in helping to sequence the GSI-locus.

物理世界と情報世界をつなぐソフトインターフェース

This article proposes a concept of soft interface for the connection between physical world where robots act and information world where robot intelligence is realized. First, this author summarizes modeling and control of object grasping and manipulation performed by a pair of soft fingertips. This author points out that a soft fingertip works as a soft interface for stable grasping and manipulation. This author also introduces two-stage control law for stable manipulation by a pair of 2-DOF fingers based on qualitative mapping between control variables and state variables. The proposed control law includes soft interface to cope with uncertainties in real world. This mapping-based approach is then applied to the control of a flexible arm based on polar coordinates.

The maternal-effect gene cellular island encodes aurora B kinase and is essential for furrow formation in the early zebrafish embryo.

Females homozygous for a mutation in cellular island (cei) produce embryos with defects in cytokinesis during early development. Analysis of the cytoskeletal events associated with furrow formation reveal that these defects include a general delay in furrow initiation as well as a complete failure to form furrow-associated structures in distal regions of the blastodisc. A linkage mapping-based candidate gene approach, including transgenic rescue, shows that cei encodes the zebrafish Aurora B kinase homologue. Genetic complementation analysis between the cei mutation and aurB zygotic lethal mutations corroborate gene assignment and reveal a complex nature of the maternal-effect cei allele, which appears to preferentially affect a function important for cytokinesis in the early blastomeres. Surprisingly, in cei mutant embryos a short yet otherwise normal furrow forms in the center of the blastodisc. Furrow formation is absent throughout the width of the blastodisc in cei mutant embryos additionally mutant for futile cycle, which lack a spindle apparatus, showing that the residual furrow signal present in cei mutants is derived from the mitotic spindle. Our analysis suggests that partially redundant signals derived from the spindle and astral apparatus mediate furrow formation in medial and distal regions of the early embryonic blastomeres, respectively, possibly as a spatial specialization to achieve furrow formation in these large cells. In addition, our data also suggest a role for Cei/AurB function in the reorganization of the furrow-associated microtubules in both early cleavage- and somite-stage embryos. In accordance with the requirement for cei/aurB in furrow induction in the early cleavage embryo, germ plasm recruitment to the forming furrow is also affected in embryos lacking normal cei/aurB function.

A formal mapping-based approach for distributed schedule coordination on projects

Construction projects involve a large number of participants with overlapping scope of work. Coordination of their activities is usually an iterative manual task undertaken by a general contractor that is often unaware of the detailed constraints of other participants. Project schedules play a key role in this coordination and form the backbone of almost all current approaches to process coordination. However, no single schedule represents the perspective of all participants involved in a project. Rather, each participant keeps in some manner a schedule for its own activities, resulting in multiple schedules that need to be coordinated. The current literature does not support simultaneous reasoning across multiple distributed, overlapping schedules. This paper introduces constructs to formalize the integration of participants’ overlapping schedules that represent the same project tasks, but use a different set breakdown structures and level of detail. Implementation of these constructs allows linking of the master schedule to the other participants’ schedules thereby representing the perspectives of all project participants. This integrated perspective facilitates initial schedule coordination and allows rapid identification of schedule conflicts in response to any schedule changes.

Index-driven similarity search in metric spaces (Survey Article)

Similarity search is a very important operation in multimedia databases and other database applications involving complex objects, and involves finding objects in a data set S similar to a query object q , based on some similarity measure. In this article, we focus on methods for similarity search that make the general assumption that similarity is represented with a distance metric d . Existing methods for handling similarity search in this setting typically fall into one of two classes. The first directly indexes the objects based on distances (distance-based indexing), while the second is based on mapping to a vector space (mapping-based approach). The main part of this article is dedicated to a survey of distance-based indexing methods, but we also briefly outline how search occurs in mapping-based methods. We also present a general framework for performing search based on distances, and present algorithms for common types of queries that operate on an arbitrary "search hierarchy." These algorithms can be applied on each of the methods presented, provided a suitable search hierarchy is defined.