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This work presents the characteristics and advantages of using complex controllers applied to space vectors. A mathematical background is presented to show that the harmonic spectrum of a space vector indicates the phase-sequence of each harmonic that composes this vector. As consequence, a reference space vector can be used for applications in which the control system has three-phase reference signals. This approach allows the implementation of complex controllers that present lower order, require less memory elements and have better dynamic response than real controllers. A literature review is made to enable a structural comparison (in terms of computational cost) between several real and complex control schemes based on the internal model principle. Two experimental applications are used to evaluate the performance of complex controllers.

Hardware cost and manufacturing process variation constrain the use of machine learning in low-cost sensor applications. This letter describes a novel method to manage some of those critical limitations. Reference calibration mapping is a method that creates a reference space from a single sensor and then transforms the output from the remaining sensor population into that reference space. The method results in the ability to utilize low-cost hardware and reduce the required training set. This letter applies the method to a media sensing system in a laser printer application. The resulting system lowered component and development costs while meeting stringent manufacturing and performance requirements

Background: In transcranial direct current stimulation (tDCS), the injected current becomes distributed across the brain areas. The objective is to stimulate the target region of interest (ROI) while minimizing the current in non-target ROIs (the ‘focality’ of tDCS). For this purpose, determining the appropriate current dose for an individual is difficult. Aim: To introduce a dose–target determination index (DTDI) to quantify the focality of tDCS and examine the dose–focality relationship in three different populations. Method: Here, we extended our previous toolbox i-SATA to the MNI reference space. After a tDCS montage is simulated for a current dose, the i-SATA(MNI) computes the average (over voxels) current density for every region in the brain. DTDI is the ratio of the average current density at the target ROI to the ROI with a maximum value (the peak region). Ideally, target ROI should be the peak region, so DTDI shall range from 0 to 1. The higher the value, the better the dose. We estimated the variation of DTDI within and across individuals using T1-weighted brain images of 45 males and females distributed equally across three age groups: (a) young adults (20 ≤ x ˂ 40 years), (b) mid adults (40 ≤ x ˂ 60 years), and (c) older adults (60 ≤ x ˂ 80 years). DTDI’s were evaluated for the frontal montage with electrodes at F3 and the right supraorbital for three current doses of 1 mA, 2 mA, and 3 mA, with the target ROI at the left middle frontal gyrus. Result: As the dose is incremented, DTDI may show (a) increase, (b) decrease, and (c) no change across the individuals depending on the relationship (nonlinear or linear) between the injected tDCS current and the distribution of current density in the target ROI. The nonlinearity is predominant in older adults with a decrease in focality. The decline is stronger in males. Higher current dose at older age can enhance the focality of stimulation. Conclusion: DTDI provides information on which tDCS current dose will optimize the focality of stimulation. The recommended DTDI dose should be prioritized based on the age (&gt, 40 years) and sex (especially for males) of an individual. The toolbox i-SATA(MNI) is freely available.

Intracranial Hemorrhage is a common brain injury that leads to a high mortality rate without prompt recognition. To address these issues, computer-aid diagnosis tools are rapidly being developed along with neural-network-based techniques to provide fast, reliable analysis and achieve accurate diagnosis decisions based on medical images. One of the most interesting applications in computer-aid diagnosis is Image Registration due to its practical features in clinical diagnosis and treatment planning. In this study, we present the non-rigid image registration for the 3D Computed Tomography image dataset of the Intracranial Hemorrhage Brain. By utilizing the affine transformation and a neural network model, we aim to predict the deformation vector field, map the real-world-collected dataset to the reference space and overcome the shifting data problem between the data analysis experiment on standard and real-world medical image analysis. Our test results gave that good registration performance is obtained in a very short time by using a neural network model, and the affine transformation significantly improves the real-world image registration. In addition, according to the distance from the hematoma area change ratio to the brain area change ratio, the characteristics of the major structure are determined to be preserved.

Atendiendo al protagonismo gradual cobrado por la Bahía de Cádiz en el comercio atlántico nuestra propuesta pretende estudiar la evolución constructiva del sistema defensivo del enclave portuario gaditano de La Caleta durante los siglos XVI-XVIII. En nuestro análisis abordaremos los factores naturales, sociales y estratégicos que harían de La Caleta un espacio natural de referencia que actuaría como dinamizador de los intercambios (poblacionales, culturales), y en la misma medida de resguardo defensivo de la ciudad. Taking into account the gradual role played by the Bay of Cádiz in Atlantic trade, our proposal aims to study the constructive evolution of the defensive system of the Cadiz port enclave of La Caleta during the 16th-18th centuries. In our analysis we will address the natural, social and strategic factors that would make La Caleta a natural reference space that would act as a catalyst for exchanges (population, cultural), and to the same extent as a defensive shelter for the city.

The introduction of virtual reality into the teleoperation system can enhance the three-dimensional and immersive sense of visual feedback, but the serious cybersickness caused by it needs to be solved urgently. Scholars have proposed many methods proceed from the hardware or software aspect to alleviate cybersickness but increased the user's mental burden and physical exertion to some extent. Inspired by the static frame hypothesis (RFH), this research proposes a method to alleviate cybersickness by rendering virtual reference space in the virtual environment. This method aims to build a three-dimensional reference space through the rendering plane to help users establish a stable feeling on the ground of the real environment in the virtual environment, thereby alleviating cybersickness. The experiment results show that rendering the reference space in a virtual teleoperation environment can significantly alleviate the cybersickness. Specifically, the total cybersickness score (TS) of participants in the virtual environment with a reference space was significantly lower than that of a virtual environment without a reference space (0.023*), a decrease of 9%. Among them, the SSQ-D score of participants in the virtual environment with a reference space is significantly lower than the virtual environment without reference space (p < 0.001***), which is reduced by 19.7%.

To summarize the distribution of glioma location within a patient population, registration of individual MR images to anatomical reference space is required. In this study, we quantified the accuracy of MR image registration to anatomical reference space with linear and non-linear transformations using estimated tumor targets of glioblastoma and lower-grade glioma, and anatomical landmarks at pre- and post-operative time-points using six commonly used registration packages (FSL, SPM5, DARTEL, ANTs, Elastix, and NiftyReg). Routine clinical pre- and post-operative, post-contrast T1-weighted images of 20 patients with glioblastoma and 20 with lower-grade glioma were collected. The 2009a Montreal Neurological Institute brain template was used as anatomical reference space. Tumors were manually segmented in the patient space and corresponding healthy tissue was delineated as a target volume in the anatomical reference space. Accuracy of the tumor alignment was quantified using the Dice score and the Hausdorff distance. To measure the accuracy of general brain alignment, anatomical landmarks were placed in patient and in anatomical reference space, and the landmark distance after registration was quantified. Lower-grade gliomas were registered more accurately than glioblastoma. Registration accuracy for pre- and post-operative MR images did not differ. SPM5 and DARTEL registered tumors most accurate, and FSL least accurate. Non-linear transformations resulted in more accurate general brain alignment than linear transformations, but tumor alignment was similar between linear and non-linear transformation. We conclude that linear transformation suffices to summarize glioma locations in anatomical reference space.

In 4D T2* placental MRI studies, motion correction is generally considered a prerequisite for quantitative analysis. However, the existing approaches use only global spatio-temporal alignment based on the classical 3D nonrigid registration and do not correct inter-slice motion. Alignment of T2* and T2 volumes in one reference space could also address the limitation of low resolution of T2* stacks and allow analysis of finer anatomical features. This work introduces a novel pipeline for motion correction in 4D T2* and 3D T2*+T2 placental MRI datasets based on the deformable slice-to-volume registration (DSVR) method. The pipelines are evaluated on 60 T2* placental MRI datasets.

Este artículo describe el significado de aquí, acá, ahí, allí y allá en el español mexicano desde la semántica cognoscitiva. El paradigma se distribuye binariamente con base en las variables: 1) modo de construcción de la escena, en que la terminación -á contrasta con -í en grados de subjetividad; 2) integración de ego en el espacio de referencia, en que acá representa la integración total y allá, la separación impuesta por algún obstáculo conceptual; 3) el dominio de ego, en que aquí designa las localizaciones que están en este dominio; y 4) la focalidad, en que allí designa localizaciones que se encuentran en una región no-focal y ahí, las que se encuentran en una región focal. Como consecuencia de su valor más objetivo y focal, ahí asume el papel de miembro no-marcado de la categoría.

This chapter proposes a geocritical reading of a rather inconspicuous place in Denmark which nonetheless stands out by virtue of its strikingly insistent appearance in Danish literature during the past three years. To read geocritically means, in Bertrand Westphal’s phrasing, to examine “the multifocalization of viewpoints on a given reference space,” and this is precisely what the place that will be examined here makes possible, since quite a lot has actually been written about it recently.Following Westphal, I shall regard the specific place that is of interest here, Amager Fælled (or in English, Amager Common) as a place whose specificity engenders specific movements within the literature that interacts with it.

We discuss automating the calculation of weak shape derivatives in the Unified Form Language (Aln{\ae}s et al., ACM Trans. Math. Softw., 2014) by introducing an appropriate additional step in the pullback from physical to reference space that computes G\^ateaux derivatives with respect to the coordinate field. We illustrate the ease of use with several examples.

IntroductionWhile image coregistration is inevitable and quantitative parametric maps, such as R2* and QSM, are increasingly used in multi-parametric studies of the brain, there is a lack of investigations on the reliability of quantitative metrics after coregistration. The purposes of this study were 1) to evaluate the reliability of R2* and QSM at 7T and 2) to assess the statistical agreement in the quantitative metrics obtained by two different coregistration approaches.MethodsWe compared the reliability of R2* and quantitative susceptibility maps obtained from brains of eight healthy participants by two coregistration approaches: 1) transformation of pre-processed quantitative maps and 2) processing quantitative maps after transformation using pixel- and ROI-based analyses. Two-sample Kolmogorov-Smirnov, Mann-Whitney U, Paired T, Intraclass-correlation tests were performed appropriately.ResultsR2* remained invariant regardless of the cogeneration timing. However, magnetic susceptibility was significantly altered when processed in transformed space, whereas it remained invariant in all KS-tests and pixel values were only different in 2 out of 64 U-tests for direct QSM coregistration. Paired t-test revealed that ROI-based group-mean R2* was invariant to both approaches, while group-mean susceptibility was invariant to direct coregistration but differed in one structure processed in transformed space. For all pairs of measurements of R2*, ICCs were excellent. ICCs for magnetic susceptibility were excellent when processed in its native space while the ICCs were lower than 0.9 or poor when processed in transformed space. Further analysis revealed that the choice of interpolation approach affected the resultant QSM.ConclusionsOur study shows that R2* could be safely processed in a transformed space, whereas QSM was less reliable when processed in the transformed space. Hence, caution is advised when using QSM in a multi-parametric study, and it is strongly recommended to process QSM in its native space prior to any coregistration or spatial transformation.

Most of the people who access the internet are millennial generation, that is, the generation born between 1982 and 2000. Digitalization forces the mass media in Indonesia to participate in meeting the demands of society's need for up to date information. This study aims to examine the practices of the millennial generation in consuming online news. In particular, this study aims to reveal the diversity of meanings that arise from the experiences of audiences when consuming online news. This study applies a qualitative approach to the reception method. The comment column provides a reference space for itself to continue consuming the next news activity on the mass media or not. Comments can even be termed as a filter for news that millennial generation will consume. Storytelling as millennial generation's online news consuming experience. From the point of view of millennials storytelling helps facilitate their imagination through visual means.

Background The Allen Institute recently built a set of high-throughput experimental pipelines to collect comprehensive in vivo surveys of physiological activity in the visual cortex of awake, head-fixed mice. Developing these large-scale, industrial-like pipelines posed many scientific, operational, and engineering challenges. New method Our strategies for creating a cross-platform reference space to which all pipeline datasets were mapped required development of 1) a robust headframe, 2) a reproducible clamping system, and 3) data-collection systems that are built, and maintained, around precise alignment with a reference artifact. Results When paired with our pipeline clamping system, our headframe exceeded deflection and reproducibility requirements. By leveraging our headframe and clamping system we were able to create a cross-platform reference space to which multi-modal imaging datasets could be mapped. Comparison with existing methods Together, the Allen Brain Observatory headframe, surgical tooling, clamping system, and system registration strategy create a unique system for collecting large amounts of standardized in vivo datasets over long periods of time. Moreover, the integrated approach to cross-platform registration allows for multi-modal datasets to be collected within a shared reference space. Conclusions Here we report the engineering strategies that we implemented when creating the Allen Brain Observatory physiology pipelines. All of the documentation related to headframe, surgical tooling, and clamp design has been made freely available and can be readily manufactured or procured. The engineering strategy, or components of the strategy, described in this report can be tailored and applied by external researchers to improve data standardization and stability.

Resumo: Este artigo teve como objetivo analisar as acoes do Programa Nacional de Promocao do Acesso ao Mundo do Trabalho (ACESSUAS TRABALHO) sob a otica dos profissionais da rede socioassistencial do Municipio de Sobral (CE), a partir de suas experiencias. Para tanto, apresenta os resultados de uma pesquisa exploratoria de natureza analitica, realizada junto a dez profissionais da referida rede, por meio da aplicacao de questionarios e realizacao de grupo focal. Corroborando os dados empiricos apresenta reflexoes teoricas tomando de emprestimo ideias de autores como Araujo e Lima (2014), Colombo (2009), Lima (2010), entre outros, alem da utilizacao de pesquisa documental. Resultados apontaram satisfatoria acao de implementacao dos objetivos do programa, entraves na articulacao e planejamento das acoes, necessidade de outras acoes para inclusao de usuarios com baixa escolaridade e a ampliacao das acoes da Agencia de Inclusao Produtiva como espaco fisico de referencia para encaminhamento dos usuarios qualificados ao mundo do trabalho. Palavras-Chaves: Acessuas Trabalho. Inclusao Produtiva. Mundo do Trabalho. Abstract: This article aims to analyze the actions of the National Program for the Promotion of Access to the World of Work (ACESSUAS JOB) from the perspective of social assistance network professionals in the city of Sobral (CE), from their experiences. It presents the results of an exploratory research of analytical nature, conducted with ten professionals of the network, through the use of questionnaires and conducting focus group. Corroborating empirical evidence presents theoretical reflections borrowing ideas from authors such as Araujo and Lima (2014), Colombo (2009), Lima (2010), among others, and the use of documentary research. Results showed satisfactory action of implementation of the program objectives, barriers in coordination and planning of actions, the need for other actions to include users with low education and further actions of the Productive Inclusion Agency as physical reference space for referral of qualified users the world of work. Key Words : Acessuas work. Productive Inclusion. World of Work. Normal 0 21 false false false PT-BR X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabela normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

We present an efficient system for synthesizing textures over fluid surfaces in a solid texturing context. The technique is simple and intuitive for artists using modern, commercially available fluid simulators. Instead of working with 2D surface maps like other fluid texture synthesis approaches, we advect 3D reference space transforms with the fluid simulation. The reference transforms are then projected onto the final surface mesh with a radius of influence control, and used for solid texturing lookup. Ray intersections of the fluid surface interpolate any transforms with overlapping control radii to determine the reference lookup of the solid texture. The final texture exhibits excellent spatial and temporal coherence with none of the artifacts that plagued previous map based approaches.

Currently, the humeral head portion of the artificial shoulder joint is usually designed by approximating it to a sphere or an ellipse. The differences between the approximated shape and the actual shape of the humeral head could limit the shoulder motion. Toward artificial shoulder joint design, this study introduces a method of constructing a 3-D statistical shape model (SSM) of the humeral head from a set of healthy subjects with CT images of the shoulder. Firstly, the humerus region is segmented from CT images, and then the anatomical coordinate system of the segmented humerus regions is determined. Secondly, each humerus region is aligned to a common reference space by using the determined anatomical coordinate system of the humeral head. Finally, 3-D SSM of the humeral head is constructed by applying principal component analysis to the aligned images. The method was validated by generalization ability, and satisfactory outcome was obtained which reveals its potential applicability toward artificial shoulder joint design in future.

Contains fulltext : 191436.pdf (Publisher’s version ) (Open Access) Comparing the brains of related species faces the challenges of establishing homologies whilst accommodating evolutionary specializations. Here we propose a general framework for understanding similarities and differences between the brains of primates. The approach uses white matter blueprints of the whole cortex based on a set of white matter tracts that can be anatomically matched across species. The blueprints provide a common reference space that allows us to navigate between brains of different species, identify homologous cortical areas, or to transform whole cortical maps from one species to the other. Specializations are cast within this framework as deviations between the species' blueprints. We illustrate how this approach can be used to compare human and macaque brains. 15 p.

El siguiente artículo se propone recuperar la gestión cultural del republicano español exiliado en Montevideo Benito Milla entre los años 1950 y 1965. Desde su arribo a Montevideo, alentado por sus ideales anarquistas, Milla configura un espacio de referencia para la cultura uruguaya que va reconfigurando una izquierda humanista y antibelicista. A través de sus revistas Cuadernos Internacionales, Deslinde, Letras 62, Número (2ª. época) y Temas, pero también a través de las editoriales que crea para la difusión de los nuevos talentos de la Generación del 45: Deslinde y Alfa, se constituye en un eslabón fundamental para comprender la fuerte expansión de la cultura uruguaya en esos años., The following article aims to recover the cultural management of the Spanish republican exiled in Montevideo Benito Milla between the 1950s and 1965s. Since his arrival in Montevideo, encouraged by his anarchist ideals, Milla sets up a reference space for the Uruguayan culture that is reconfiguring a humanist and anti-war left wing. Through its magazines Cuadernos Internacionales, Deslinde, Letras 62, Número (2nd ep.) and Temas, but also through the editorials that he creates for the diffusion of the new talents of the Generation of 45: Deslinde and Alfa, Milla constitutes himself in a fundamental link to understand the strong expansion of Uruguayan culture in those years., Dossier: Publicaciones periódicas y redes culturales en América Latina, Facultad de Humanidades y Ciencias de la Educación

Neuroinformatics 16(1), 65-80 (2018). doi:10.1007/s12021-017-9349-6, Published by Springer, New York, NY

A stochastic implementation of the Multiple Mapping Conditioning (MMC) approach has been applied to a turbulent piloted jet diffusion flame (Sandia flame F) that is close to extinction. Two classic mixing models (Curl’s and IEM) are introduced in the MMC context to model the turbulent mixing. The suggested model involves the use of a reference space (that is mapped to mixture fraction space) in order to define particle proximity. The addition of the MMC ideas to the IEM and Curl’s models, that is suggested in the current work, aspires to combine the simplicity of these two models with the enforced compositional locality without violating the linearity and independence principles. The formulation of the approach is discussed in detail and results are presented for the mixing field and reactive species. The predictions are compared with joint-scalar PDF simulations using the same mixing models and experimental data. Moreover, the sensitivity of the model to the particle number is examined. It is shown that MMC is less sensitive to the number of particles and can generally produce improved predictions of major and minor chemically reacting species with a lower number of particles.

An effective method is proposed to estimate the desired-signal (S) subspace by the intersection between the signal-plus-interference (SI) subspace and a reference space covering the angular region where the desired signal is located. The estimated S subspace is robust to steering vector mismatch and overestimation of the SI subspace, capable of detecting the relative strength of the desired signal. And even the basis of the estimated S subspace can serve as an effective estimation of the steering vector of the desired signal. With these properties, the estimated S subspace can help to select a more accurate narrow area for searching for the steering vector of the desired signal in mismatch cases. The proposed method is applied for robust adaptive beamforming with an improved performance, as demonstrated by simulation results.

Population level analysis of medical imaging data relies on finding spatial correspondence across individuals as a basis for local comparison of visual characteristics. Here, we describe and evaluate a framework to normalize routine images covering different parts of the human body, in different modalities to a common reference space. The framework performs two basic steps towards normalization: (1) The identification of the location and coverage of the human body by an image and (2) a non-linear mapping to the common reference space. Based on these mappings, either coordinates, or label-masks can be transferred across a population of images. We evaluate the framework on a set of routine CT and MR scans exhibiting large variability on location and coverage. A set of manually annotated landmarks is used to assess the accuracy and stability of the approach. We report distinct improvement in stability and registration accuracy compared to a classical single-atlas approach.

Drosophila melanogaster, commonly known as fruit fly, is an important genetic model organism for fundamental neuroscience research. The central nervous system of the larva consists of about 12,000 neurons. For efficient information retrieval and automated data mining, each patterns needs to be mapped onto a common reference space. Accurate image registration plays a key role here. We investigate standard and multi-channel image registration approaches. Our evaluation shows that multi-channel registration is beneficial in cases where the staining quality is partially compromised and can be complemented by the information contained in an additional reference channel.

Areas of the fusiform gyrus (FG) within human ventral temporal cortex (VTC) process high-level visual information associated with faces, limbs, words, and places. Since classical cytoarchitectonic maps do not adequately reflect the functional and structural heterogeneity of the VTC, we studied the cytoarchitectonic segregation in a region, which is rostral to the recently identified cytoarchitectonic areas FG1 and FG2. Using an observer-independent and statistically testable parcellation method, we identify 2 new areas, FG3 and FG4, in 10 human postmortem brains on the mid-FG. The mid-fusiform sulcus reliably identifies the cytoarchitectonic transition between FG3 and FG4. We registered these cytoarchitectonic areas to the common reference space of the single-subject Montreal Neurological Institute (MNI) template and generated probability maps, which reflect the intersubject variability of both areas. Future studies can relate in vivo neuroimaging data with these microscopically defined cortical areas to functional parcellations. We discuss these results in the context of both large-scale functional maps and fine-scale functional clusters that have been identified within the human VTC. We propose that our observer-independent cytoarchitectonic parcellation of the FG better explains the functional heterogeneity of the FG compared with the homogeneity of classic cytoarchitectonic maps.

Groundbreaking advances in volume electron microscopy and specimen preparation are enabling the 3-dimensional visualisation of specimens with unprecedented detail, and driving a gratifying resurgence of interest in the ultrastructural examination of cellular systems. Serial section techniques, previously the domain of specialists, are becoming increasingly automated with the development of systems such as the automatic tape-collecting ultramicrotome, and serial blockface and focused ion beam scanning electron microscopes. These changes are rapidly broadening the scope of biomedical studies to which volume electron microscopy techniques can be applied beyond the brain. Further innovations in microscope design are also in the pipeline, which have the potential to enhance the speed and quality of data collection. The recent introduction of integrated light and electron microscopy systems will revolutionise correlative light and volume electron microscopy studies, by enabling the sequential collection of data from light and electron imaging modalities without intermediate specimen manipulation. In doing so, the acquisition of comprehensive functional information and direct correlation with ultrastructural details within a 3-dimensional reference space will become routine. The prospects for volume electron microscopy are therefore bright, and the stage is set for a challenging and exciting future.

Multiple mapping conditioning (MMC) explicitly includes a link between the physical velocity and the conditioning variable. The usual method of obtaining values for the conditional physical velocity is to define the value of the conditioning variable and use a model for the velocity. In contrast to the conditional moment closure (CMC) approach, the conditioning variable is not a real quantity and hence provides greater flexibility in its definition. The hybrid binomial Langevin–MMC model has the advantage of naturally incorporating velocity–scalar interactions through the binomial Langevin model and the joint probability density function (PDF) is here used to define a reference variable for the MMC part of the model. The current approach has the advantage that difficulties encountered with the binomial Langevin model in modeling scalars with non-elementary bounds are removed. The formulation of the closure leads to locality in scalar space and permits the use of simple approaches for transport in the reference space. The evaluation of the technique is here extended to a jet flame with moderately-high levels of extinction (Sandia Flame E). A direct comparison with experimental data and the EMST (Euclidean minimum spanning tree) model for temperature, species concentrations and burning indexes suggests that the approach performs well.