Journal articles: 'Boundary artifacts'

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Reeves, S. J. "Fast image restoration without boundary artifacts." IEEE Transactions on Image Processing 14, no. 10 (October 2005): 1448–53. http://dx.doi.org/10.1109/tip.2005.854474.

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Hovden, Robert, Yi Jiang, Huolin L. Xin, and Lena F. Kourkoutis. "Periodic Artifact Reduction in Fourier Transforms of Full Field Atomic Resolution Images." Microscopy and Microanalysis 21, no. 2 (January 19, 2015): 436–41. http://dx.doi.org/10.1017/s1431927614014639.

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AbstractThe discrete Fourier transform is among the most routine tools used in high-resolution scanning/transmission electron microscopy (S/TEM). However, when calculating a Fourier transform, periodic boundary conditions are imposed and sharp discontinuities between the edges of an image cause a cross patterned artifact along the reciprocal space axes. This artifact can interfere with the analysis of reciprocal lattice peaks of an atomic resolution image. Here we demonstrate that the recently developed Periodic Plus Smooth Decomposition technique provides a simple, efficient method for reliable removal of artifacts caused by edge discontinuities. In this method, edge artifacts are reduced by subtracting a smooth background that solves Poisson’s equation with boundary conditions set by the image’s edges. Unlike the traditional windowed Fourier transforms, Periodic Plus Smooth Decomposition maintains sharp reciprocal lattice peaks from the image’s entire field of view.

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Aghdasi, F., and R. K. Ward. "Reduction of boundary artifacts in image restoration." IEEE Transactions on Image Processing 5, no. 4 (April 1996): 611–18. http://dx.doi.org/10.1109/83.491337.

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Luna-Reyes, Luis Felipe, Natalie Helbig, and Xiaoyi Yerden. "Performance Information Artifacts." International Journal of Public Administration in the Digital Age 8, no. 1 (January 2021): 1–16. http://dx.doi.org/10.4018/ijpada.20210101.oa6.

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The field of performance management is premised on the centrality of measurement and performance information use in everyday decision making and practice. Information is managed through the use of information systems, but research shows that implementing these technological systems is not enough. This research responds to recent calls for a better understanding of performance information use and the role of dialogue among stakeholders in promoting learning and system change. Through case analysis and qualitative modeling, it proposes the concept of performance information artifacts, and the need for effective boundary spanners to promote effective learning and knowledge sharing in performance dialogue.

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Bardsley, Johnathan M., and Aaron Luttman. "Dealing with boundary artifacts in MCMC-based deconvolution." Linear Algebra and its Applications 473 (May 2015): 339–58. http://dx.doi.org/10.1016/j.laa.2014.09.023.

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Matakos, A., S. Ramani, and J. A. Fessler. "Accelerated Edge-Preserving Image Restoration Without Boundary Artifacts." IEEE Transactions on Image Processing 22, no. 5 (May 2013): 2019–29. http://dx.doi.org/10.1109/tip.2013.2244218.

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Reed, Mark S. C., and K. M. Flurchick. "Investigation of artifacts due to periodic boundary conditions." Computer Physics Communications 95, no. 1 (May 1996): 39–46. http://dx.doi.org/10.1016/0010-4655(95)00140-9.

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Sorel, M. "Removing Boundary Artifacts for Real-Time Iterated Shrinkage Deconvolution." IEEE Transactions on Image Processing 21, no. 4 (April 2012): 2329–34. http://dx.doi.org/10.1109/tip.2011.2176344.

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Gošić, Milena. "Skeuomorphism, Boundary Objects and Socialization of the Chalcolithic Metallurgy in the Southern Levant." Issues in Ethnology and Anthropology 10, no. 3 (February 28, 2016): 717. http://dx.doi.org/10.21301/eap.v10i3.8.

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Metalworking emerged in the southern Levant as a new ritual practice during the late phase of the Ghassulian culture, ca. 4300–3900 BC. Ghassulian metalworkers cast objects in both pure and alloyed copper. All the artifacts produced during this time span were ritual. The aim of the present paper is to discuss the socialization process of the Ghassulian metallurgy and its copper objects, by using the concepts of skeuomorphism and boundary objects. Ghassulian copper artifacts can be divided into two groups. The first group consists of artifacts, such as maceheads, chisels and axes, which were produced in stone before the Ghassulian metallurgy appeared. The second group consists of artifacts produced only in metal, including scepters, standards, “crowns” and horns, which were decorated by motifs found on various other early and late Ghassulian ritual artifacts. The artifacts of the first group are skeuomorphic objects, the morphology of which was widely recognized in early and late Ghassulian contexts. These were boundary objects, belonging both to the realm of the new social world of metallurgy and the preexisting world of Ghassulian ritual behavior. Their purpose was to introduce metallurgy to people, both in the Beer Sheva settlements and in other parts of the southern Levant, who did not practice it, as a technology firmly rooted in the Ghassulian tradition. The second group consists of more innovative objects that demonstrated the transformational potential of metallurgy and the superior control metalworkers had over the material world

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Heidari, A. Homayoun, and Murthy N. Guddati. "Highly accurate absorbing boundary conditions for wide-angle wave equations." GEOPHYSICS 71, no. 3 (May 2006): S85—S97. http://dx.doi.org/10.1190/1.2192914.

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We develop a new class of absorbing boundary conditions (ABCs) to prevent unwanted artifacts and wraparounds associated with aperture truncation in migration/modeling using high-order, one-way wave equations. The fundamental approach behind the proposed development is the efficient discretization of the half-space, beyond the boundary of interest, using midpoint-integrated imaginary finite elements, an idea recently utilized in the development of effective one-way wave equations. The proposed absorbing boundary conditions essentially add absorbing layers at the aperture truncation points. We derive the absorbing boundary conditions, analyze their properties, and develop a stable explicit finite-difference scheme to solve the downward-continuation problem modified by these boundary conditions. With the help of numerical examples, we conclude that with as few as three absorbing layers, i.e., two additional gridpoints, the waves can be absorbed completely, thus preventing associated artifacts.

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Lee, Dohoon, Yoonmo Yang, and Byung Tae Oh. "Boundary Artifacts Reduction in View Synthesis of 3D Video System." Journal of Broadcast Engineering 21, no. 6 (November 30, 2016): 878–88. http://dx.doi.org/10.5909/jbe.2016.21.6.878.

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Mark, Gloria, Kalle Lyytinen, and Mark Bergman. "Boundary Objects in Design: An Ecological View of Design Artifacts." Journal of the Association for Information Systems 8, no. 11 (November 2007): 546–68. http://dx.doi.org/10.17705/1jais.00144.

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Kremer, Raymond J., Mysore A. Dayananda, and Alexander H. King. "Room-temperature grain boundary diffusion data measured from historical artifacts." Zeitschrift für Metallkunde 96, no. 10 (October 2005): 1187–92. http://dx.doi.org/10.3139/146.101160.

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Lee, Ji-Yeon, and Nam-Yong Lee. "Cause Analysis and Removal of Boundary Artifacts in Image Deconvolution." Journal of Korea Multimedia Society 17, no. 7 (July 30, 2014): 838–48. http://dx.doi.org/10.9717/kmms.2014.17.7.838.

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He, Yaofeng, and Ru-Shan Wu. "One-way/one-return boundary-element method and salt internal multiples." GEOPHYSICS 75, no. 3 (May 2010): T63—T69. http://dx.doi.org/10.1190/1.3374463.

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Surface-related multiples or internal multiples can produce artifacts in migrated images using one-way wave-equation methods. Salt-body-related internal-multiple removal remains a challenging problem for this approach. To investigate the effects of salt-body-related internal multiples on subsalt imaging, the boundary-element method is implemented in a one-way/one-return scheme to separate the primary transmission/reflection arrivals at the salt boundaries from the internal multiples. Numerical results demonstrate that the proposed method is effective for modeling primary transmission/reflection arrivals through/from irregular interfaces between strong-velocity-contrast media. Internal multiples are obtained through straight subtraction of primary reflection arrivals from full reflected-wave data. The image from prestack depth migration of these pure internal multiples using one-way propagators is compatible with some strong artifacts in the subsalt region from migration of full-wave data using the same one-way propagators. Results suggest that a significant part of artifacts in the subsalt region in the prestack image for the 2D SEG-EAGE salt model using one-way propagators might be caused by salt internal multiples.

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Lee, Charlotte P. "Boundary Negotiating Artifacts: Unbinding the Routine of Boundary Objects and Embracing Chaos in Collaborative Work." Computer Supported Cooperative Work (CSCW) 16, no. 3 (April 27, 2007): 307–39. http://dx.doi.org/10.1007/s10606-007-9044-5.

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Singh, Singara. "Tile Boundary Artifacts Reduction of JPEG2000 Compressed Images Using Neighboring Samples." International journal of Multimedia & Its Applications 4, no. 1 (February 29, 2012): 127–36. http://dx.doi.org/10.5121/ijma.2012.4111.

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Pulliam, R. Jay, and Philip B. Stark. "Bumps on the core-mantle boundary: Are they facts or artifacts?" Journal of Geophysical Research: Solid Earth 98, B2 (February 10, 1993): 1943–55. http://dx.doi.org/10.1029/92jb02692.

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Cai, Yuantao, Marco Donatelli, Davide Bianchi, and Ting-Zhu Huang. "Regularization Preconditioners for Frame-Based Image Deblurring with Reduced Boundary Artifacts." SIAM Journal on Scientific Computing 38, no. 1 (January 2016): B164—B189. http://dx.doi.org/10.1137/140976261.

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Byeungwoo Jeon and Jechang Jeong. "Blocking artifacts reduction in image compression with block boundary discontinuity criterion." IEEE Transactions on Circuits and Systems for Video Technology 8, no. 3 (June 1998): 345–57. http://dx.doi.org/10.1109/76.678634.

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Zhu, Wen Hua. "Boundary Stitching Method for Block-Based Parallel Error Diffusion." Applied Mechanics and Materials 738-739 (March 2015): 560–63. http://dx.doi.org/10.4028/www.scientific.net/amm.738-739.560.

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In this paper, we describe a boundary stitching method for block-based parallel error diffusion algorithm. A blocked strategy is used to separate the original image into independent blocks. Overlapping areas across adjacent blocks and initial error of boundary pixels are introduce to eliminate the boundary artifacts. Experimental results show that the proposed method generates high quality images similar to that of the original algorithm.

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Wang, Lei, Juan Deng, Shu Zhao, Hong Wang, Hong Sha, and Yan Wang. "Influence of Boundary Deformation on Image Reconstruction in Electrical Impedance Tomography." Journal of Medical Imaging and Health Informatics 10, no. 10 (October 1, 2020): 2274–78. http://dx.doi.org/10.1166/jmihi.2020.3171.

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For electrical impedance tomography (EIT) lung imaging, chest expansion and contraction could change the electrode placement and deform the boundary of the image area, which changes the electric field distribution and distorts the reconstructed images. EIT images of lung function often produce severe artifacts due to the expansion of the thoracic cage, so it is necessary to study the effect of thoracic boundary deformation on EIT images. In this paper, we established several elliptical image reconstruction models, which deform from 1% to 15% in the anterior–posterior (AP) dimension from the circle field domain, to emulate chest expansion. The Quantitative evaluation of the influence of the deformation on the reconstruction images has been made. Images are estimated by parameter DORI and SSIM. The results show that these two parameters can evaluate image quality effectively, and image error increases with the increasing of boundary deformation. Although the error is small when the deformation extent of the boundary shape is small, images are seriously distorted when the deformation increases. Image error increases significantly when the boundary deformation increases, which may lead to image artifacts and maybe result in misdiagnosis.

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Mittet, Rune. "Implementation of the Kirchhoff integral for elastic waves in staggered‐grid modeling schemes." GEOPHYSICS 59, no. 12 (December 1994): 1894–901. http://dx.doi.org/10.1190/1.1443576.

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Implementation of boundary conditions in finite‐difference schemes is not straightforward for the elastic wave equation if a staggered grid formulation is used. Reverse time migration of VSP data requires a proper description of the recording surface so as not to excite false P‐ and S‐waves. Such contributions may cause artifacts in the imaging procedure. The boundary conditions for the elastic stress tensor can be implemented numerically in a staggered coarse grid modeling scheme by using band‐limited spatial delta‐functions and band‐limited first‐order derivatives of these spatial delta‐functions. A representation theorem for elastic waves is derived to test the implementation of the spatial part of the boundary condition. The implementation is tested in a 2-D numerical experiment for a closed, but curved, boundary S enclosing a volume V. The test condition is that within the volume V, the difference between the forward modeled field and the retropropagated field should be equal to zero. Both P‐ and S‐waves are properly recovered in a 2-D reverse time modeling example. The numerical artifacts related to the proposed spatial approximation of the boundary condition are found to be negligible.

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Partheepan, R., J. Raja Paul Perinbam, M. Krishnamurthy, and N. R. Shanker. "Visualization of Pterygomaxillary Fissure Structure and Shape in CT Image via Non-Linear Perspective Projection." Journal of Medical Imaging and Health Informatics 11, no. 6 (June 1, 2021): 1580–89. http://dx.doi.org/10.1166/jmihi.2021.3809.

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The neurologist analyses the brain images to diagnose disease via structure and shape of the part in scanned Medical images such as CT, MRI, and PET. The Medical image segmentation performs less in the regions where no or little contrast, artifacts over the different boundary regions. The manual process of segmentation shows poor boundary differentiation due to discernibility in shape and location, intra and inter observer reliability. In this paper, we propose dyadic CAT optimization (DCO) algorithm to segment the regions in the brain from CT and MRI image via Non-linear perspective Foreground and Back Ground projection. The DCO algorithm removes the artifacts in the boundary regions and provide the exact structure and shape of the brain regions. The DCO algorithm shows the region boundary for pterygomaxillary fissure, occipital lobe, vaginal process zygomatic arch, maxilla and piriform aperture in brain image with high visibility in the regions of inadequately visible boundary and distinguishes the deformable shape. The DCO algorithm applies on 50 images and eight images with complex bone and muscle mass structure for performance evaluation. The DCO algorithm shows the increased Structural similarity index (SSIM) with 90% accuracy.

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Evans, M. W. "On the isolation of possible artifacts due to cubic periodic boundary conditions." Computer Physics Communications 59, no. 3 (July 1990): 495–97. http://dx.doi.org/10.1016/0010-4655(90)90090-n.

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Demin Wang, Liang Zhang, and A. Vincent. "New method for reducing GOP-boundary artifacts in wavelet-based video coding." IEEE Transactions on Broadcasting 52, no. 3 (September 2006): 350–55. http://dx.doi.org/10.1109/titb.2006.879850.

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Bai, Zheng-Jian, Daniele Cassani, Marco Donatelli, and Stefano Serra-Capizzano. "A fast alternating minimization algorithm for total variation deblurring without boundary artifacts." Journal of Mathematical Analysis and Applications 415, no. 1 (July 2014): 373–93. http://dx.doi.org/10.1016/j.jmaa.2014.01.061.

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Kostis, Angelos, and Paavo Ritala. "Digital Artifacts in Industrial Co-creation: How to Use VR Technology to Bridge the Provider-Customer Boundary." California Management Review 62, no. 4 (June 12, 2020): 125–47. http://dx.doi.org/10.1177/0008125620931859.

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Industrial co-creation projects are often complex and ambiguous, involving high levels of interpretive uncertainty over processes and outcomes. To boost the effectiveness of such projects, firms have increasingly adopted virtual reality (VR) technology and have experienced unique benefits by utilizing digital artifacts—interactive objects in digital environments, such as factory installation layouts or design visualizations. This article provides case evidence demonstrating how VR-enabled digital artifacts support firms to effectively implement tailor-made solutions in robotics and automation projects. The adoption of new digital co-creation practices redefines the traditional customer-provider roles in industrial co-creation, increasing engagement, reducing uncertainty, and improving project outcomes.

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Wang, Guanglei, Pengyu Wang, Yan Li, Tianqi Su, Xiuling Liu, and Hongrui Wang. "A Motion Artifact Reduction Method in Cerebrovascular DSA Sequence Images." International Journal of Pattern Recognition and Artificial Intelligence 32, no. 08 (April 8, 2018): 1854022. http://dx.doi.org/10.1142/s0218001418540228.

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Digital Subtraction Angiography (DSA) can be used for diagnosing the pathologies of vascular system including systemic vascular disease, coronary heart disease, arrhythmia, valvular disease and congenital heart disease. Previous studies have provided some image enhancement algorithms for DSA images. However, these studies are not suitable for automated processes in huge amounts of data. Furthermore, few algorithms solved the problems of image contrast corruption after artifact removal. In this paper, we propose a fully automatic method for cerebrovascular DSA sequence images artifact removal based on rigid registration and guided filter. The guided filtering method is applied to fuse the original DSA image and registered DSA image, the results of which preserve clear vessel boundary from the original DSA image and remove the artifacts by the registered procedure. The experimental evaluation with 40 DSA sequence images shows that the proposed method increases the contrast index by 24.1% for improving the quality of DSA images compared with other image enhancement methods, and can be implemented as a fully automatic procedure.

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Akoumianakis, D., N. Vidakis, G. Vellis, D. Kotsalis, G. Milolidakis, A. Plemenos, A. Akrivos, and D. Stefanakis. "Transformable boundary artifacts for knowledge-based work in cross-organization virtual communities spaces." Intelligent Decision Technologies 5, no. 1 (January 5, 2011): 65–82. http://dx.doi.org/10.3233/idt-2011-0098.

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Shi, Xingchen, Weijian Mao, and Xulei Li. "Elastic Gaussian-beam migration for four-component ocean-bottom seismic data." GEOPHYSICS 85, no. 1 (November 22, 2019): S11—S19. http://dx.doi.org/10.1190/geo2018-0716.1.

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Multimode and multicomponent elastic Gaussian-beam migration is attractive for its efficiency, flexibility, and accuracy. However, when it is used for ocean-bottom seismic data, the incomplete boundary condition will yield some nonphysical artifacts in the final migrated images. To solve this problem, we extend the elastic Gaussian-beam migration method from 3C to 4C by introducing the pressure recording to represent the stress tensor on the ocean bottom. Based on the elastic wave equation and the complete boundary condition for the ocean-bottom model, we derive effective formulas of accurate multimode wave downward continuation. With our method, different wave modes are separated and the receiver ghost is removed simultaneously by applying a decomposition matrix to 4C data during the migration without prior data separation and deghosting, which eliminates the artifacts better and reduces the processing cost. Three synthetic experiments were provided to validate the method for 4C ocean-bottom data migration.

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Liang, Hong, and Houzhu Zhang. "Wavelet-domain reverse time migration image enhancement using inversion-based imaging condition." GEOPHYSICS 84, no. 5 (September 1, 2019): S401—S409. http://dx.doi.org/10.1190/geo2018-0400.1.

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Reverse time migration (RTM) is implemented by solving the two-way wave equation using recorded data as boundary conditions. The full wave equation can simulate wave propagation in all directions; thus, RTM has no dip limitations and is capable of imaging complex structures. Because wavefields are allowed to travel in all directions, the source and receiver wavefields can be scattered back from strong velocity contrasts. The crosscorrelation of head waves, diving waves, and backscattered waves along a raypath can lead to strong artifacts in the RTM image. These artifacts degrade the final image quality. An inversion-based imaging condition that computes the weighted sum of a time derivative image and a spatial gradient image can significantly reduce the RTM artifacts. Based on the multiscale directional selectivity property of the wavelet transform, we have developed a new method to compute the weighting function for the inversion-based imaging condition in the wavelet domain. The unique property of this approach is that the weighting function depends on the spatial locations, wavenumber, and local directions. This multidimensional property allows us to selectively remove the RTM image artifacts while preserving useful energy. We determine the effectiveness of our method for attenuating RTM artifacts using synthetic examples.

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Akoumianakis, Demosthenes. "Antecedents of Boundary Spanning E-Collaboration." International Journal of e-Collaboration 11, no. 2 (April 2015): 47–73. http://dx.doi.org/10.4018/ijec.2015040104.

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Spanning boundaries has emerged as a key topic in the scholarship on distributed organizing. Nonetheless, most of the works are motivated by boundaries designated by static demarcations of time and/or place, while only recently there is some evidence emphasizing the dynamic aspects of boundaries and boundary spanning. Following the latter tradition, the present research attempts to examine the antecedents of boundary spanning in the context of e-collaboration. This is approached using a cross case assessment of two interpretive case studies. The results suggest that cross-organizational e-collaboration can be analyzed in relation to five constructs: (a) representations through which collaborative engagements are attained; (b) the affordances of the (social) medium for reconfiguring agency, both human and non-human; (c) boundary negotiating artifacts; (d) source of togetherness and sense of community; and (e) type of enacted cyber-structures. It turns out that these five constructs can be used to anchor and qualify a range of boundary spanning e-collaboration regimes.

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Baker, Ian, and Daniel Cullen. "SEM/EDS observations of impurities in polar ice: artifacts or not?" Journal of Glaciology 49, no. 165 (2003): 184–90. http://dx.doi.org/10.3189/172756503781830773.

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AbstractA series of experiments was undertaken to determine the origin of filaments found in grain boundaries and impurity spots found in grain interiors of polar ice during observation in the scanning electron microscope. It is shown that although the filaments are artifacts, they demonstrate the presence of impurities segregated to the grain boundary planes. It is also demonstrated that the impurities observed in the grain interior reside there and were not transported from the grain boundaries during specimen preparation or observation.

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Sandhu, Amanpreet Kaur. "An Efficient Lossless Compression algorithm for Medical images." Turkish Journal of Computer and Mathematics Education (TURCOMAT) 12, no. 3 (April 10, 2021): 3793–99. http://dx.doi.org/10.17762/turcomat.v12i3.1663.

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Medical image compression plays a vital role in diagnosis of diseases which allowing manipulation, efficient, transmission and storage of color, binary and grayscale image. Before transmission and storage, a medical image may be required to be compressed. The objective of the study is to develop an efficient and effective technique for digital medical images which alleviates the blocking artifacts from grayscale image while retaining all relevant structures. In this paper, we demonstrate a highly engineered postprocessing filtering approach has been designed to remove blocking effects from medical images at low bit rate. The proposed technique is comprised of three strategies i.e. 1) a threshold valve scheme which is used to capture the pixel vectors containing blocking artifacts. 2) Blocking artifacts measurement techniques. The blocking artifacts are measured by three frequency related modes (low, Moderate and high frequency model). 3) A directional filter which is used to remove over-smoothing and ringing artifacts near edges of block boundary. The algorithm is tested on digital medical grayscale images from different modalities. The experimental results illustrate that the proposed technique is more efficient on the basis of PSNR-B, MSSIM, and MOS indices than the state-of-the-art methods. The proposed algorithm can be seamlessly applied in area of medical image compression which high transmission efficiency and acceptable image quality can be guaranteed.

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Hertweck, Thomas, Christoph Jäger, Alexander Goertz, and Jörg Schleicher. "Aperture effects in 2.5D Kirchhoff migration: A geometrical explanation." GEOPHYSICS 68, no. 5 (September 2003): 1673–84. http://dx.doi.org/10.1190/1.1620641.

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Seismic images obtained by Kirchhoff time or depth migration are always accompanied by some artifacts known as migration noise, migration boundary effects, or diffraction smiles, which may severely affect the quality of the migration result. Most of these undesirable effects are caused by a limited aperture if the algorithms make no special disposition to avoid them. Strong amplitude variation along reflection events may cause similar artifacts. All of these effects can be explained mathematically by means of the method of stationary phase. However, such a purely theoretical explication is not always easily understood by applied geophysicists. A geometrical interpretation of the terms of the stationary‐phase approximation in relation to the diffraction and reflection traveltime curves in the time domain can help to develop a more intuitive understanding of the migration artifacts. A simple numerical experiment for poststack (zero‐offset) data indicates the problem and helps to demonstrate the effects and the methods to avoid them.

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ElNaghy, Hanan, and Leo Dorst. "Boundary Morphology for Hierarchical Simplification of Archaeological Fragments." Mathematical Morphology - Theory and Applications 4, no. 1 (July 22, 2020): 46–63. http://dx.doi.org/10.1515/mathm-2020-0101.

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AbstractWhen fitting archaeological artifacts, one would like to have a representation that simplifies fragments while preserving their complementarity. In this paper, we propose to employ the scale-spaces of mathematical morphology to hierarchically simplify potentially fitting fracture surfaces. We study the masking effect when morphological operations are applied to selected subsets of objects. Since fitting locally depends on the complementarity of fractures only, we introduce ‘Boundary Morphology’ on surfaces rather than volumes. Moreover, demonstrating the Lipschitz nature of the terracotta fractures informs our novel extrusion method to compute both closing and opening operations simultaneously. We also show that in this proposed representation the effects of abrasion and uncertainty are naturally bounded, justifying the morphological approach. This work is an extension of our contribution earlier published in the proceedings of ISMM2019 [10].

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Watanabe, Hiroshi C., and Qiang Cui. "Quantitative Analysis of QM/MM Boundary Artifacts and Correction in Adaptive QM/MM Simulations." Journal of Chemical Theory and Computation 15, no. 7 (May 16, 2019): 3917–28. http://dx.doi.org/10.1021/acs.jctc.9b00180.

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Wiącek, Urszula, and Urszula Woźnicka. "Feasibility study of artifacts on the neutron logging curve near the boundary of layers." Acta Geophysica 67, no. 6 (July 6, 2019): 1721–29. http://dx.doi.org/10.1007/s11600-019-00322-1.

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Wegemer, Christopher M., and Jennifer Renick. "Boundary Spanning Roles and Power in Educational Partnerships." AERA Open 7 (January 2021): 233285842110168. http://dx.doi.org/10.1177/23328584211016868.

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Research-practice partnerships (RPPs) offer promising approaches to improve educational outcomes. Navigating boundaries between contexts is essential for RPP effectiveness, yet much work remains to establish a conceptual framework of boundary spanning in partnerships. Our longitudinal comparative case study draws from our experiences as graduate student boundary spanners in three long-term partnerships to examine boundary spanning roles in RPPs, with particular attention to the ways in which power permeates partnership work. Using qualitative, critically reflexive analysis of meeting artifacts and field notes, we found that our boundary spanning roles varied along five spectrums: institutional focus, task orientation, expertise, partnership disposition, and agency. Our roles were shaped by the organizational, cultural, relational, and historical features of the partnerships and contexts of interaction. We aim to promote the development of effective RPP strategies by leveraging the perspectives and positionality of graduate students in order to advance understanding of boundary spanning roles.

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Kim, Sang Chul, Hyo Min Kim, and Sung Il Chien. "Threshold Variation Based on Triangular Probability Density Function for Error Diffusion Halftoning." Advanced Materials Research 462 (February 2012): 676–83. http://dx.doi.org/10.4028/www.scientific.net/amr.462.676.

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This paper proposes an error diffusion based halftoning technique of which the threshold is randomly varied to minimize well-known artifacts often observed in the standard method by introducing a triangular probability density function. The diffusion of error is adaptively adjusted depending upon the magnitude of an edge to preserve boundary quality in a half-toned image.

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Mele, Cristina, Roberta Sebastiani, and Daniela Corsaro. "Service innovation as a social construction: The role of boundary objects." Marketing Theory 19, no. 3 (November 2018): 259–79. http://dx.doi.org/10.1177/1470593118809794.

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This article advances a conceptualization of service innovation as socially constructed through resource integration and sensemaking. By developing this view, the current study goes beyond an outcome perspective, to include the collective nature of service innovation and the role of the social context in affecting the service innovation process. Actors enact and perform service innovation through two approaches, one that is more concerted and another that emerges in some way. Each approach is characterized by distinct resource integration processes, in which the boundary objects (artifacts, discourses, and places) play specific roles. They act as bridge-makers that connect actors, thereby fostering resource integration and shared meanings.

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Whyte, Jennifer, and Tamara Nussbaum. "Transition and Temporalities: Spanning Temporal Boundaries as Projects End and Operations Begin." Project Management Journal 51, no. 5 (June 3, 2020): 505–21. http://dx.doi.org/10.1177/8756972820919002.

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As projects end and operations begin, we argue that transition involves boundary-spanning work to ensure continuity across changing forms of organizing. A study of transition in the London megaproject ecology (Heathrow Terminal 5, London 2012 Olympics, and Crossrail) is used to build new theoretical insight into how transition is accomplished. We find that multiple temporalities meet and disjunctures emerge, with stability to close projects sought as interorganizational futures shift. Our work extends the research on temporal boundary spanning, to articulate how disjunctures and shifts are managed, and continuity is enhanced, through the use of artifacts, procedures, soft landings, and tests.

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Kang, Donghyun, and James Evans. "Against method: Exploding the boundary between qualitative and quantitative studies of science." Quantitative Science Studies 1, no. 3 (September 2020): 930–44. http://dx.doi.org/10.1162/qss_a_00056.

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Quantitative and qualitative studies of science have historically played radically different roles with opposing epistemological commitments. Using large-scale text analysis, we see that qualitative studies generate and value new theory, especially regarding the complex social and political contexts of scientific action, while quantitative approaches confirm existing theory and evaluate the performance of scientific institutions. Large-scale digital data and emerging computational methods could allow us to refigure these positions, turning qualitative artifacts into quantitative patterns into qualitative insights across many scales, heralding a new era of theory development, engagement, and relevance for scientists, policy-makers, and society.

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Boresch, Stefan, and Othmar Steinhauser. "Presumed versus real artifacts of the Ewald summation technique: The importance of dielectric boundary conditions." Berichte der Bunsengesellschaft für physikalische Chemie 101, no. 7 (July 1997): 1019–29. http://dx.doi.org/10.1002/bbpc.19971010706.

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Cohn, Marisa Leavitt, Susan Elliott Sim, and Charlotte P. Lee. "What Counts as Software Process? Negotiating the Boundary of Software Work Through Artifacts and Conversation." Computer Supported Cooperative Work (CSCW) 18, no. 5-6 (October 17, 2009): 401–43. http://dx.doi.org/10.1007/s10606-009-9100-4.

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Park, Jae-Hyeung, Han-Ju Yeom, Hee-Jae Kim, HuiJun Zhang, BoNi Li, Yeong-Min Ji, and Sang-Hoo Kim. "Removal of line artifacts on mesh boundary in computer generated hologram by mesh phase matching." Optics Express 23, no. 6 (March 19, 2015): 8006. http://dx.doi.org/10.1364/oe.23.008006.

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Bühl, Johannes, Ronny Engelmann, and Albert Ansmann. "Removing the Laser-Chirp Influence from Coherent Doppler Lidar Datasets by Two-Dimensional Deconvolution." Journal of Atmospheric and Oceanic Technology 29, no. 8 (August 1, 2012): 1042–51. http://dx.doi.org/10.1175/jtech-d-11-00144.1.

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Abstract A chirped laser pulse can introduce artifacts into datasets of coherent Doppler wind lidars. At close vicinity of strong signal peaks undesired artificial velocities can be measured and continuous signals can be shifted by a constant factor. It is shown how to remove these artifacts and how to retrieve accurate velocity estimations from both clouds and the planetary boundary layer. Therefore, a two-dimensional deconvolution technique is applied to the wind lidar datasets in order to correct the chirp effect in the range and frequency space. The chirp correction for a 1-h measurement of vertical velocities in the atmosphere is presented. The method is applied to the averaged Doppler spectra. Therefore, no access to the raw heterodyne signal is necessary. The complexity of the data acquisition software and the amount of data to be stored is hereby significantly reduced. Simulations suggest that the remaining velocity error resulting from the laser pulse chirp is smaller than 0.02 m s−1 and chirp-induced artifacts are removed reliably. The method also increases the signal resolution in the range and frequency dimension and can be applied for this intent even if there is no chirp.

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Mariano, Stefania, and Yukika Awazu. "The role of collaborative knowledge building in the co-creation of artifacts: influencing factors and propositions." Journal of Knowledge Management 21, no. 4 (July 10, 2017): 779–95. http://dx.doi.org/10.1108/jkm-09-2016-0360.

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Purpose This paper assesses the role of collaborative knowledge building in the co-creation of artifacts in the knowledge management field. Design/methodology/approach Fifty-eight papers published in six knowledge management-related journals were analyzed. The framework for analysis included 13 codes. Studies were analyzed using qualitative and quantitative methods. Findings Findings showed that several factors influenced the co-creation of artifacts in collaborative knowledge building. At the micro level, individual motivation, capabilities and reflexivity seemed to play a central role in co-creation processes. At the meso level, teamwork and shared understanding were identified as two key major factors. At the macro level, structural, behavioral and cognitive factors were identified; they included organizational rules and workplace setting, organizational culture and learning and memory. Managerial agency, characteristics of artifacts and knowledge brokers and boundary spanners also seemed to have an influence at the inter-organizational levels of analysis. Research limitations/implications This study has limitations related to scope of contribution, covered time span (17 years) and restrictions in journal subscriptions. Practical implications The study will help managers understand the intricacies of collaborative knowledge building practices to increase organizational overall effectiveness and performance. Originality/value This study is a first attempt to systematically assess the role of collaborative knowledge building in the co-creation of artifacts, and therefore, it represents a primary reference in the knowledge management field. It proposes some initial propositions that can guide future empirical studies.

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FURUKAWA, Yoshiyuki, and Hiroshi MASUDA. "2313 Advances in Research into Artifacts (14th Report) : 3D Contents Compression and Transferring Using Boundary Curves." Proceedings of Design & Systems Conference 2001.11 (2001): 200–203. http://dx.doi.org/10.1299/jsmedsd.2001.11.200.

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Journal articles on the topic 'Boundary artifacts'

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