204 research outputs found

    Compensating for Large In-Plane Rotations in Natural Images

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    Rotation invariance has been studied in the computer vision community primarily in the context of small in-plane rotations. This is usually achieved by building invariant image features. However, the problem of achieving invariance for large rotation angles remains largely unexplored. In this work, we tackle this problem by directly compensating for large rotations, as opposed to building invariant features. This is inspired by the neuro-scientific concept of mental rotation, which humans use to compare pairs of rotated objects. Our contributions here are three-fold. First, we train a Convolutional Neural Network (CNN) to detect image rotations. We find that generic CNN architectures are not suitable for this purpose. To this end, we introduce a convolutional template layer, which learns representations for canonical 'unrotated' images. Second, we use Bayesian Optimization to quickly sift through a large number of candidate images to find the canonical 'unrotated' image. Third, we use this method to achieve robustness to large angles in an image retrieval scenario. Our method is task-agnostic, and can be used as a pre-processing step in any computer vision system.Comment: Accepted at Indian Conference on Computer Vision, Graphics and Image Processing (ICVGIP) 201

    Dynamic Response of Vertical and Batter Piles

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    The lateral forced vibration test was carried out on driven cast in-situ concrete vertical piles of 500 mm diameter in a petrochemical complex site in Paradip, India. The site predominantly consists of silty sand for the top 3 m with shear wave velocity of 200 m/s and it is followed by clayey sand with shear velocity increases from 415 m/s to 460 m/s over pile termination depth of about 17 m . The piles were subjected to a sinusoidal lateral force with magnitude of 0.3 kN to 9.5 kN in the frequency range of 5 to 30 Hz. A 3D finite element analysis was carried out on vertical piles using ABAQUS and its results are validated with the field test results. Finite element analysis was extended to batter piles (10˚and 20˚) subjected to lateral dynamic load and it was found that the peak displacement amplitude of batter piles is 15 to 25% less than the same that of vertical piles indicating better performance of batter piles under lateral dynamic loading

    Effective Stress v/s Total Stress Ground Response Analyses for a Typical Site in Chennai (India)

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    This paper presents the results of ground response analyses carried out for a typical sandy site in Chennai city by equivalent linear and nonlinear total and effective stress approaches. The soil profile at the site consists of 26m thick sandy layer with SPT blow count increases from 16 to above 50 with depth. The shear wave velocity profile measured using field Multichannel Analysis of Surface Wave (MASW) test is found to increase from 170 m/s to 400 m/s at 26m depth. The equivalent linear ground response analysis was carried out using SHAKE2000. The nonlinear total and effective stress analyses were performed using D-MOD2000. In the nonlinear total stress analysis, the Modified Kondner and Zelasko (MKZ) constitutive model was used. In the case of nonlinear effective stress analysis, modulus degradation and stress degradation models of Matasovic and Vucetic (1993) were used to incorporate the pore pressure parameters. The analyses were carried out for a time history of bedrock acceleration with PGA of 0.16g obtained from the seismic hazard analysis. The results of the analyses are presented in terms of ground acceleration, shear stress and shear strain. The results of the equivalent linear, nonlinear total and effective stress analyses show similar ground response characteristics except marginal variation in the period corresponding to the peak spectral acceleration due to low intensity of input motion

    Measurement of Vibration in Berthing Structure During Underwater Rock Blasting

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    Blasting, in particular underwater rock blasting is the most challenging and least understood source of vibration, which may cause considerable damage to the safety of the adjacent buildings and structures and including berthing structures. Though the blast-induced vibration is best controlled by specification of blasting procedures, it is very essential to measure and monitor the blast-induced vibration of the adjacent structures to access its safety. This paper discusses the measurement and monitoring of underwater blast induced vibration on the berthing structure (berth No.8) at Tuticorin in southern part of India. The vibration is recorded using three acceleration transducers mounted on the deck slab of berthing structure and monitored using a data efficiency system consisting of HBM make multi channel carrier frequency amplifier system with digital storage oscilloscope. It is observed that the peak vertical acceleration is much higher than the longitudinal and lateral peak acceleration, because of vibration of deck slab along with frequency of ground excitation. The peak particle velocity (PPV) is obtained from the time history of acceleration by simple integration. From the spectral analysis, the predominant frequency is found as 26 Hz. For this frequency the allowable PPV value is established from various standards as 25mm/sec. The measured PPV values fro all blasts (31 nos) are well below the limit of allowable PPV value, except in few blasts, which shows the berth is safe against underwater blast induced vibration. Pre and post crack survey also proves that there is no considerable damage to the berthing structure

    Evaluation of Rock Characteristics for a Power Plant Site in India

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    Extensive geotechnical and geophysical investigations were carried out for a power plant site situated on the east coast of southern India. It is proposed to construct the foundation on rock at a depth of 18.0 m below the ground level. The geological and geotechnical characterization of the rock have been presented in this paper. Extensive boreholes were drilled up to 40.0 m to 60.0 m depth and a few boreholes up to 120.0 m depth from the ground level. Seismic crosshole tests were conducted at soil/rock strata upto 65.0 m depth for the determination of S-wave and P-wave velocity at different depths. Dilatometer tests were conducted in weathered and hard rock at 5.0 m interval up to a depth of 65.0 m. Field permeability tests were carried out in deep boreholes by single packer method. Various laboratory tests including UCC, Brazilian, and Point load tests were carried out on rock core samples. Modules obtained from UCC tests are compared with the in-situ modulus obtained from Dilatometer tests. Bearing capacity and settlement analysis are carried out for the proposed raft of about 113 m x 105 m size to be supported on rock. The allowing bearing pressure is estimated based on Rock Mass Rating, RQD and strength of rock cores. The settlement analysis is carried out using modulus obtained from Dilatometer tests and from the laboratory unconfined compression tests on rock core samples. The modulus of subgrade reaction and spring constants in vertical, horizontal and rocking modes of vibration are also evaluated for the static and seismic analysis of the raft

    Preclinical activity and determinants of response of the GPRC5DxCD3 bispecific antibody talquetamab in multiple myeloma.

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    Cell surface expression levels of GPRC5D, an orphan G protein-coupled receptor, are significantly higher on multiple myeloma (MM) cells, compared with normal plasma cells or other immune cells, which renders it a promising target for immunotherapeutic strategies. The novel GPRC5D-targeting T-cell redirecting bispecific antibody, talquetamab, effectively kills GPRC5D+ MM cell lines in the presence of T cells from both healthy donors or heavily pretreated MM patients. In addition, talquetamab has potent anti-MM activity in bone marrow (BM) samples from 45 patients, including those with high-risk cytogenetic aberrations. There was no difference in talquetamab-mediated killing of MM cells from newly diagnosed, daratumumab-naïve relapsed/refractory (median of 3 prior therapies), and daratumumab-refractory (median of 6 prior therapies) MM patients. Tumor cell lysis was accompanied by T-cell activation and degranulation, as well as production of pro-inflammatory cytokines. High levels of GPRC5D and high effector:target ratio were associated with improved talquetamab-mediated lysis of MM cells, whereas an increased proportion of T cells expressing PD-1 or HLA-DR, and elevated regulatory T-cell (Treg) counts were associated with suboptimal killing. In cell line experiments, addition of Tregs to effector cells decreased MM cell lysis. Direct contact with bone marrow stromal cells also impaired the efficacy of talquetamab. Combination therapy with daratumumab or pomalidomide enhanced talquetamab-mediated lysis of primary MM cells in an additive fashion. In conclusion, we show that the GPRC5D-targeting T-cell redirecting bispecific antibody talquetamab is a promising novel antimyeloma agent. These results provide the preclinical rationale for ongoing studies with talquetamab in relapsed/refractory MM

    Comprehensive analysis of human microRNA target networks

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    <p>Abstract</p> <p>Background</p> <p>MicroRNAs (miRNAs) mediate posttranscriptional regulation of protein-coding genes by binding to the 3' untranslated region of target mRNAs, leading to translational inhibition, mRNA destabilization or degradation, depending on the degree of sequence complementarity. In general, a single miRNA concurrently downregulates hundreds of target mRNAs. Thus, miRNAs play a key role in fine-tuning of diverse cellular functions, such as development, differentiation, proliferation, apoptosis and metabolism. However, it remains to be fully elucidated whether a set of miRNA target genes regulated by an individual miRNA in the whole human microRNAome generally constitute the biological network of functionally-associated molecules or simply reflect a random set of functionally-independent genes.</p> <p>Methods</p> <p>The complete set of human miRNAs was downloaded from miRBase Release 16. We explored target genes of individual miRNA by using the Diana-microT 3.0 target prediction program, and selected the genes with the miTG score ≧ 20 as the set of highly reliable targets. Then, Entrez Gene IDs of miRNA target genes were uploaded onto KeyMolnet, a tool for analyzing molecular interactions on the comprehensive knowledgebase by the neighboring network-search algorithm. The generated network, compared side by side with human canonical networks of the KeyMolnet library, composed of 430 pathways, 885 diseases, and 208 pathological events, enabled us to identify the canonical network with the most significant relevance to the extracted network.</p> <p>Results</p> <p>Among 1,223 human miRNAs examined, Diana-microT 3.0 predicted reliable targets from 273 miRNAs. Among them, KeyMolnet successfully extracted molecular networks from 232 miRNAs. The most relevant pathway is transcriptional regulation by transcription factors RB/E2F, the disease is adult T cell lymphoma/leukemia, and the pathological event is cancer.</p> <p>Conclusion</p> <p>The predicted targets derived from approximately 20% of all human miRNAs constructed biologically meaningful molecular networks, supporting the view that a set of miRNA targets regulated by a single miRNA generally constitute the biological network of functionally-associated molecules in human cells.</p
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