Parallel Projection Research Articles

Mold’s Dominion: Science, Empire, and Capitalism in a Globalizing World

Abstract Today, Jōkichi Takamine and Albert Calmette are known for their contribution to the history of medicine. Yet their early careers centered not on medicine, but on biotechnology, and on parallel projects to bring a food processing technology used across Asia to new audiences around the world. In the end, they both succeeded, but in very different ways. Takamine would make his fortune with “Taka-Diastase,” a patent digestive aid once popular around the world; Calmette would help develop the “Amylo Process” of industrial brewing and distilling used as the basis of exploitative alcohol monopolies in colonial Indochina and Formosa. Understanding how a single technology could take on two radically different forms provides a unique opportunity to explore entanglements of science, empire, and capitalism in a globalizing world. Empires and capitalist enterprises combined to send mold along pathways that both reflected and transcended imperial boundaries. And as it traveled, mold was remade by—and in turn helped to remake—the political economies it encountered. Today, when the products of mold technologies are part of our daily lives, it’s tempting to see globalization in terms of seamless, uniform, and seemingly inevitable outcomes. This paper focuses attention instead on alternative paths, contingent and deeply inequitable processes, and the way science, empire, and capitalism produced the modern world.

Understanding young adult Muslim and Christian attitudes toward queer identity: A Canadian and UK comparison.

This article utilises data from two parallel mixed-methods projects to examine attitudes to queer identity among heterosexual Muslim and Christian young adults aged between 18 and 25 in Canada and the UK. Drawing on questionnaires, interviews and video diaries, our analysis revealed the enormous complexity regarding how participants made sense of their, largely contextually mediated, attitudes. A qualitative approach enabled us to carefully consider how these attitudes are forged, formulated and embodied, offering greater nuance and detail compared with attitudinal approaches focused solely on quantitative data. Responses by these young Muslim and Christian participants explore the fluidity and movement in the attitudes expressed, further emphasising complexity.

A parallel, non-spatial iterative, and rotational pressure projection method for the nonlinear fluid-fluid interaction

In this paper, a parallel, non-spatial iterative, and rotational pressure projection method for the coupled Navier-Stokes equations is proposed and developed. As for each Navier-Stokes equation, one elliptic equation and one Possion equation at each time step determine the values of the velocity and pressure, respectively. Moreover, we only need to solve four simple linear equations, and the computational time of the whole system is greatly reduced. The rotational pressure projection method achieves the same accuracy as the traditional decoupled fractional time-stepping method. Furthermore, we apply the presented method, the rotational pressure projection method and the linear decoupled fractional time-stepping method to the submarine mountain problem. Compared to the streamline diagrams of these three methods from two aspects of accuracy and CPU times, we obtain that the presented method has good parallelism and is the most efficient method, the rotational pressure projection method is more efficient than the traditional decoupled fractional time-stepping method. Finally, numerical results verify that our proposed method has the high efficiency.

Máscarasdo Bem: An analysis of face-mask performance from a volunteer mask-making initiative in Ribeirão Preto, Brazil

ObjectivesThis study examines the response of a group of volunteers in Ribeirão Preto, Brazil, as the city faced an unprecedented demand for face masks during the onset of the COVID-19 crisis in 2020. The performance of artisanal-produced masks was compared with industry equivalents. Study designCase report with comparative testing. MethodsA comparison was made between two parallel projects that produced single-use masks for healthcare workers and reusable masks for the community. Mask samples were tested for filtration efficiency (FE) and breathability (pressure drop). ResultsResults for FE averaged 40–60% for healthcare masks and 10% for community masks; both types of masks were tested for particle sizes of 0.3 ​μm. ConclusionsWhile performance was inferior to standard comparators, the masks investigated in this study afforded a level of protection in the absence of alternatives, especially in non-aerosol generating contexts. The findings of this study are useful for communities with limited resources in other developing countries. In addition, insights can be gained from the experiences in Ribeirão Preto in terms of how to respond to future health emergencies.

Accelerating iterative CT reconstruction algorithms using Tensor Cores

Tensor Cores are specialized hardware units added to recent NVIDIA GPUs to speed up matrix multiplication-related tasks, such as convolutions and densely connected layers in neural networks. Due to their specific hardware implementation and programming model, Tensor Cores cannot be straightforwardly applied to other applications outside machine learning. In this paper, we demonstrate the feasibility of using NVIDIA Tensor Cores for the acceleration of a non-machine learning application: iterative Computed Tomography (CT) reconstruction. For large CT images and real-time CT scanning, the reconstruction time for many existing iterative reconstruction methods is relatively high, ranging from seconds to minutes, depending on the size of the image. Therefore, CT reconstruction is an application area that could potentially benefit from Tensor Core hardware acceleration. We first studied the reconstruction algorithm’s performance as a function of the hardware related parameters and proposed an approach to accelerate reconstruction on Tensor Cores. The results show that the proposed method provides about 5 times increase in speed and energy saving using the NVIDIA RTX 2080 Ti GPU for the parallel projection of 32 images of size 512times 512. The relative reconstruction error due to the mixed-precision computations was almost equal to the error of single-precision (32-bit) floating-point computations. We then presented an approach for real-time and memory-limited applications by exploiting the symmetry of the system (i.e., the acquisition geometry). As the proposed approach is based on the conjugate gradient method, it can be generalized to extend its application to many research and industrial fields.

Intelligent Recognition and Teaching of English Fuzzy Texts Based on Fuzzy Computing and Big Data

In this paper, we conduct in‐depth research and analysis on the intelligent recognition and teaching of English fuzzy text through parallel projection and region expansion. Multisense Soft Cluster Vector (MSCVec), a multisense word vector model based on nonnegative matrix decomposition and sparse soft clustering, is constructed. The MSCVec model is a monolingual word vector model, which uses nonnegative matrix decomposition of positive point mutual information between words and contexts to extract low‐rank expressions of mixed semantics of multisense words and then uses sparse. It uses the nonnegative matrix decomposition of the positive pointwise mutual information between words and contexts to extract the low‐rank expressions of the mixed semantics of the polysemous words and then uses the sparse soft clustering algorithm to partition the multiple word senses of the polysemous words and also obtains the global sense of the polysemous word affiliation distribution; the specific polysemous word cluster classes are determined based on the negative mean log‐likelihood of the global affiliation between the contextual semantics and the polysemous words, and finally, the polysemous word vectors are learned using the Fast text model under the extended dictionary word set. The advantage of the MSCVec model is that it is an unsupervised learning process without any knowledge base, and the substring representation in the model ensures the generation of unregistered word vectors; in addition, the global affiliation of the MSCVec model can also expect polysemantic word vectors to single word vectors. Compared with the traditional static word vectors, MSCVec shows excellent results in both word similarity and downstream text classification task experiments. The two sets of features are then fused and extended into new semantic features, and similarity classification experiments and stack generalization experiments are designed for comparison. In the cross‐lingual sentence‐level similarity detection task, SCLVec cross‐lingual word vector lexical‐level features outperform MSCVec multisense word vector features as the input embedding layer; deep semantic sentence‐level features trained by twin recurrent neural networks outperform the semantic features of twin convolutional neural networks; extensions of traditional statistical features can effectively improve cross‐lingual similarity detection performance, especially cross‐lingual topic model (BL‐LDA); the stack generalization integration approach maximizes the error rate of the underlying classifier and improves the detection accuracy.

Respuesta a Daniel Garber, Las cuestiones metafísicas de la dinámica

This text is an answer to Daniel Garber’s article. In the reply, I challenge the idea that the dynamics is a parallel project, incompatible with the monadological project. To criticize this position, I present the importance of the conceptualization of action from Dynamica de potentia (1690) and its implications for the monadological metaphysics itself.

Online simulation to monitor multiphase flow using laser source as transmitter

This research presents an application of optical tomography for the detection of gas bubbles flowing in a liquid medium. In order to visualise the material inside the pipeline, parallel beam projection had been selected. However, while producing the image, some constraints such as diffraction and reflection in liquid medium will happen, where it will affect the flow accuracy of the result. Therefore, a laser source is used to produce a better image resolution. The column is exposed to a homogeneous light beam and then the ray is detected with the use of optical wave guided detectors. By using parallel projection for 44 laser transmitters and photodiode receivers at the cross-sectional boundary, the existence of bubbles inside a vertical column pipeline is determined. The voltage drop at the sensor directly shows the existence of bubbles between the transmitter and receiver. Linear Back-projection (LBP) is the algorithm that is used to reconstruct the image in real-time. In conclusion, the technique of using parallel beam projection with a laser source can improve the image quality in liquid phase and enables the percentage size of bubbles to be determined.

Surface-Based Path Following Control: Application of Curved Tapes on 3-D Objects

In this article, a novel approach for the versatile wrinkle-free application of (curved) precut adhesive tapes on freeform 3-D surfaces is presented. Straight and curved tape application paths are mapped onto the 3-D object as geodesics and as lines with imposed geodesic curvature, respectively. The proposed surface-based path following control concept extends the classical path following control by a novel parallel contact frame and a parallel projection operator. Using a static state feedback, the robotic system is transformed into a system with linear input-output behavior in the path coordinates. This allows to traverse a path on a 3-D object with a draping roll without turning around the surface normal vector. The latter prevents distortions and wrinkles of the applied tape. Experimental results with a Kuka LBR iiwa 14 R820 demonstrate the feasibility of the proposed approach.

Efficient Channel Estimation in Massive MIMO Partially Centralized Cloud-Radio Access Network Systems

This article investigates channel estimation problem in massive MIMO partially centralized cloud-RAN (MPC-RAN). The channel estimation was realized through compressed data method to minimize the huge pilot overhead, then combined with parallel Givens data projection method (PGDPM) to form a semi-blind estimator. Comparison and analysis of improved minimum mean square error (MMSE), fast data projection method (FDPM), compressed data, and PGDPM techniques was evaluated for achievable normalized mean square error (NMSE) in MPC-RAN. The PGDPM-based estimator had the lowest normalized mean square error. The FDPM and PGDPM based methods are comparable in performance with PGDPM based estimator having a slight edge over FDPM-based estimator. This vindicates PGDPM-based estimator as a method to be utilized in channel estimation since it compresses the massive MIMO channel information, hence mitigating the fronthaul finite capacity problem, and at the same time, it is geared towards efficient parallelization for optimal BBU resource utilization.

A novel tunnel-lining crack recognition system based on digital image technology

Structural health monitoring (SHM) combined with digital image technology has been widely applied to infrastructure operation management. However, the linear illumination of the tunnel and the various lining diseases limit the quality of lining-crack recognition. In this article, a novel tunnel-lining crack recognition system is established. The system involves three main procedures: image preprocessing and enhancement, feature extraction, and crack characterization. To meet tunnel environmental conditions, mature image enhancement and morphological algorithms are packaged into the system; meanwhile, this paper proposes differentiated noise filtering and an improved segmenting method combining adaptive partitioning, edge detection and threshold method to improve the recognition accuracy. A self-regulating calibration method that uses parallel projection is also applied to crack characterization, achieving real-time size calibration. The results of experiments to compare the effects of the proposed system and field application tests confirm the stability and reliability of the system. A further deviation factor analysis provides reasonable suggestions for system improvement.

Sections and Projections of Three-Dimensional Convex Bodies

The paper discusses the following question: up to which precision, the parallel projection of a three-dimensional convex body can be approximated by the same projection of a plane section of the body.

Parallel iterative stabilized finite element algorithms for the Navier–Stokes equations with nonlinear slip boundary conditions

AbstractBased on full domain partition technique, some parallel iterative pressure projection stabilized finite element algorithms for the Navier–Stokes equations with nonlinear slip boundary conditions are designed and analyzed. In these algorithms, the lowest equal‐order P1 − P1 elements are used for finite element discretization and a local pressure projection stabilized method is used to counteract the invalidness of the discrete inf‐sup condition. Each subproblem is solved on a global composite mesh with the vast majority of the degrees of freedom associated with the particular subdomain that it is responsible for and hence can be solved in parallel with other subproblems by using an existing sequential solver without extensive recoding. All of the subproblems are nonlinear and are independently solved by three kinds of iterative methods. We estimate the optimal error bounds of the approximate solutions with the use of some (strong) uniqueness conditions. Numerical results are also given to demonstrate the effectiveness of the parallel algorithms.

Solving Extended Project Scheduling Problems

Abstract Project based planning and execution is used in various phases of a product lifecycle, starting from the conceptual idea and design through to the manufacturing and maintenance. It is common, that an enterprise or an organization executes more than one project in parallel. These projects may share the same resources and may have differing goals. Based on experience the order of task execution is a key factor, having a major impact on the key performance indicators. Our paper presents an extended model and a scheduling method for resource constrained project scheduling problems.

The domestic risk of chinese partnerships: cross-conditionality and coalition building

Empréstimos chineses se tornaram alternativas viáveis de financiamento durante a onda rosa devido à ausência de cláusulas de condicionalidade tradicionais. No entanto, essas operações financeiras, além de outras de diversos tipos, implicam com frequência a condicionalidade cruzada. Contrário à condicionalidade tradicional, a condicionalidade cruzada implica que operações nas áreas de comércio, financeira ou de ajuda ao desenvolvimento sejam prejudicadas em resposta a decisões de autoridades nacionais que mudem condições de projetos paralelos. O objetivo do presente trabalho é explorar as possíveis consequências políticas da condicionalidade cruzada nos assuntos domésticos dos países da América Latina. A hipótese é que a condicionalidade cruzada representa um risco similar àquele da condicionalidade tradicional em termos de autonomia nacional, mas por motivos diferentes. Se conclui que a condicionalidade cruzada afeta os esforços governamentais de construção de uma coalizão de governo devido aos impactos potenciais que ela possa ter sobre parceiros importantes do mesmo. No Brasil, o setor agroexportador, parceiro chave da coalizão de governo atual, seria aquele que poderia ser potencialmente afetado se o governo chinês decide implementar a condicionalidade cruzada como medida de retaliação a políticas ou declarações hostis do governo brasileiro a respeito de interesses chineses.

Multi-threaded parallel projection tetrahedral algorithm for unstructured volume rendering

Volume rendering methods have been extensively studied in recent years due to their effectiveness and expressiveness for unstructured grid data visualization. Although existing volume rendering methods have demonstrated great success, we observe that these methods have extensive interpolation and integral operations, which may adversely affect their efficiency and further prevent them being applied in interactive visualization. To boost efficiency and achieve interactive rendering rates, we propose a novel multi-threaded parallel projection tetrahedral algorithm based on multi-core architecture. By analyzing the parallelism of volume rendering methods, we find that the visibility sorting and classification/decomposition of projection polygons are the most time-consuming parts. To reduce the execution time of these two parts, we design corresponding parallel methods. In this manner, our method can dramatically improve efficiency and further enable user interactions for progressive unstructured grid analysis. The visibility sorting part includes partial sorting and global sorting: In partial sorting, we partition disordered tetrahedral depth array and obtain several loosely coupled subarrays, and in global sorting, we sort each subarray with multi-threads technique. In the classification/decomposition of projection polygons part, we normalize tetrahedral projection to ensure arbitrary tetrahedral produces the same number of triangles, and then store the produced vertex data into vertex array with offset computation that ensures correct order for the multi-threads runtime. The experimental results show that the proposed multi-threaded projection tetrahedral algorithm can achieve a speedup of 3.4X on a 20 cores CPU and outperforms the fastest VTK implementation at a speedup of 2.5X, which verifies the efficiency of our algorithm.

Pixel-density and viewing-angle enhanced integral 3D display with parallel projection of multiple UHD elemental images.

This paper presents an integral three-dimensional (3D) display that efficiently enhances both the pixel densities and viewing angles of 3D images with parallel projection of elemental images. In the proposed method, ultra-high-definition (UHD) elemental images are projected and superimposed as parallel light rays from densely arranged compact UHD projectors onto a lens array. Three-dimensional images with enhanced pixel densities and viewing angles can be displayed by optimizing the projector positions and system design. The prototype yielded a horizontal pixel density of 63.5 ppi, approximately 97,000 pixels, and a viewing angle of approximately 30°, making it superior to previous integral 3D display systems.

New methods for projecting a 3D object onto a free-form surface

PurposeThis paper aims to provide a series of new methods for projecting a three-dimensional (3D) object onto a free-form surface. The projection algorithms presented can be divided into three types, namely, orthogonal, perspective and parallel projection.Design/methodology/approachFor parametric surfaces, the computing strategy of the algorithm is to obtain an approximate solution by using a geometric algorithm, then improve the accuracy of the approximate solution using the Newton–Raphson iteration. For perspective projection and parallel projection on an implicit surface, the strategy replaces Newton–Raphson iteration by multi-segment tracing. The implementation takes two mesh objects as an example of calculating an image projected onto parametric and implicit surfaces. Moreover, a comparison is made for orthogonal projections with Hu’s and Liu’s methods.FindingsThe results show that the new method can solve the 3D objects projection problem in an effective manner. For orthogonal projection, the time taken by the new method is substantially less than that required for Hu’s method. The new method is also more accurate and faster than Liu’s approach, particularly when the 3D object has a large number of points.Originality/valueThe algorithms presented in this paper can be applied in many industrial applications such as computer aided design, computer graphics and computer vision.

Parallel residual projection: a new paradigm for solving linear inverse problems

A grand challenge to solve a large-scale linear inverse problem (LIP) is to retain computational efficiency and accuracy regardless of the growth of the problem size. Despite the plenitude of methods available for solving LIPs, various challenges have emerged in recent times due to the sheer volume of data, inadequate computational resources to handle an oversized problem, security and privacy concerns, and the interest in the associated incremental or decremental problems. Removing these barriers requires a holistic upgrade of the existing methods to be computationally efficient, tractable, and equipped with scalable features. We, therefore, develop the parallel residual projection (PRP), a parallel computational framework involving the decomposition of a large-scale LIP into sub-problems of low complexity and the fusion of the sub-problem solutions to form the solution to the original LIP. We analyze the convergence properties of the PRP and accentuate its benefits through its application to complex problems of network inference and gravimetric survey. We show that any existing algorithm for solving an LIP can be integrated into the PRP framework and used to solve the sub-problems while handling the prevailing challenges.

Role and limitations of the geometric mean method regarding head rotation in salivary gland scintigraphy: a phantom study.

To investigate the possible influence of head rotation on the results of salivary gland scintigraphy, a phantom study was designed to simulate clinical salivary gland scintigraphy. The quantitative accuracy of regional activity counts was compared for two data acquisition methods involving head rotation: (i) an anterior planar projection-only (ANT) method and (ii) a geometric mean (GM) method using both the anterior and posterior planar projections. The roles and limitations of the GM and ANT methods when used at different head rotation angles were examined. Parallel planar projections of a head phantom with four salivary gland simulators, containing 3.7 MBq 99mTc-sodium pertechnetate, at various rotational settings were acquired using a dual-head gamma camera. The difference between the standard activity counts (no phantom rotation) and the activity counts affected by the phantom rotation was calculated and defined as the rotational bias that decreased the accuracy of activity quantification. For small-angle rotation (≤10°), use of the GM method decreased the bias for all salivary gland simulators. In contrast, the bias of large-angle rotation (>10°) between four salivary gland simulators became conspicuous and complex in both methods. This bias may reflect different attenuation effects caused by displacement of the structures. Our data suggest that the GM method can be used when the head rotation angle is small (≤10°); however, when the head rotation angle is >10°, the non-negligible influence of head rotation should be considered during image acquisition.