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Sample records for fused joint segmentation

  1. Pelvic incidence-lumbar lordosis mismatch results in increased segmental joint loads in the unfused and fused lumbar spine.

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    Senteler, Marco; Weisse, Bernhard; Snedeker, Jess G; Rothenfluh, Dominique A

    2014-07-01

    Symptomatic adjacent segment disease (ASD) has been reported to occur in up to 27 % of lumbar fusion patients. A previous study identified patients at risk according to the difference of pelvic incidence and lordosis. Patients with a difference between pelvic incidence and lumbar lordosis >15° have been found to have a 20 times higher risk for ASD. Therefore, it was the aim of the present study to investigate forces acting on the adjacent segment in relation to pelvic incidence-lumbar lordosis (PILL) mismatch as a measure of spino-pelvic alignment using rigid body modeling to decipher the underlying forces as potential contributors to degeneration of the adjacent segment. Sagittal configurations of 81 subjects were reconstructed in a musculoskeletal simulation environment. Lumbar spine height was normalized, and body and segmental mass properties were kept constant throughout the population to isolate the effect of sagittal alignment. A uniform forward/backward flexion movement (0°-30°-0°) was simulated for all subjects. Intervertebral joint loads at lumbar level L3-L4 and L4-L5 were determined before and after simulated fusion. In the unfused state, an approximately linear relationship between sagittal alignment and intervertebral loads could be established (shear: 0° flexion r = 0.36, p < 0.001, 30° flexion r = 0.48, p < 0.001; compression: 0° flexion r = 0.29, p < 0.01, 30° flexion r = 0.40, p < 0.001). Additionally, shear changes during the transition from upright to 30° flexed posture were on average 32 % higher at level L3-L4 and 14 % higher at level L4-L5 in alignments that were clinically observed to be prone to ASD. Simulated fusion affected shear forces at the level L3-L4 by 15 % (L4-L5 fusion) and 23 % (L4-S1 fusion) more for alignments at risk for ASD. Higher adjacent segment shear forces in alignments at risk for ASD already prior to fusion provide a mechanistic explanation for the clinically observed correlation between PILL mismatch and rate

  2. Analysis of adjacent segment degeneration with laminectomy above a fused lumbar segment.

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    Gard, Andrew P; Klopper, Hendrik B; Doran, Stephen E; Hellbusch, Leslie C

    2013-11-01

    Although recent data suggests that lumbar fusion with decompression contributes to some marginal acceleration of adjacent segment degeneration (ASD), few studies have evaluated whether it is safe to perform a laminectomy above a fused segment. This study investigates the hypothesis that laminectomy above a fused lumbar segment does not increase the incidence of ASD, and assesses the benefits and risks of performing a laminectomy above a lumbar fusion. A retrospective review of 171 patients who underwent decompression and instrumented fusion of the lumbar spine was performed to analyze the association between ASD and laminectomy above the fused lumbar segment. Patients were divided into two groups - one group with instrumented fusion alone and the other group with instrumented fusion plus laminectomy above the fused segment. Of the 171 patients, 34 underwent additional decompressive laminectomy above the fused segment. There was a significant increase in ASD incidence as well as progression of ASD grade in both groups. There was no significant increase in ASD in patients with decompressive laminectomy above the fused lumbar segment compared to patients with laminectomy limited to the fused segment. This retrospective review of 171 patients who underwent decompression and instrumented fusion with follow-up radiographs demonstrates that laminectomy decompression above a fused segment does not significantly increase radiographic ASD. There is, however, a significant increase in ASD over time, which was observed throughout the entire cohort likely representing a natural progression of lumbar spondylosis above the fusion segment.

  3. Joint shape segmentation with linear programming

    KAUST Repository

    Huang, Qixing

    2011-01-01

    We present an approach to segmenting shapes in a heterogenous shape database. Our approach segments the shapes jointly, utilizing features from multiple shapes to improve the segmentation of each. The approach is entirely unsupervised and is based on an integer quadratic programming formulation of the joint segmentation problem. The program optimizes over possible segmentations of individual shapes as well as over possible correspondences between segments from multiple shapes. The integer quadratic program is solved via a linear programming relaxation, using a block coordinate descent procedure that makes the optimization feasible for large databases. We evaluate the presented approach on the Princeton segmentation benchmark and show that joint shape segmentation significantly outperforms single-shape segmentation techniques. © 2011 ACM.

  4. Joint Rendering and Segmentation of Free-Viewpoint Video

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    Ishii Masato

    2010-01-01

    Full Text Available Abstract This paper presents a method that jointly performs synthesis and object segmentation of free-viewpoint video using multiview video as the input. This method is designed to achieve robust segmentation from online video input without per-frame user interaction and precomputations. This method shares a calculation process between the synthesis and segmentation steps; the matching costs calculated through the synthesis step are adaptively fused with other cues depending on the reliability in the segmentation step. Since the segmentation is performed for arbitrary viewpoints directly, the extracted object can be superimposed onto another 3D scene with geometric consistency. We can observe that the object and new background move naturally along with the viewpoint change as if they existed together in the same space. In the experiments, our method can process online video input captured by a 25-camera array and show the result image at 4.55 fps.

  5. Cervical facet dislocation adjacent to the fused motion segment.

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    Yokoyama, Kunio; Kawanishi, Masahiro; Yamada, Makoto; Tanaka, Hidekazu; Ito, Yutaka; Kuroiwa, Toshihiko

    2016-01-01

    This study reports on a case that forces re-examination of merits and demerits of anterior cervical fusion. A 79-year-old male was brought to the emergency room (ER) of our hospital after he fell and struck the occipital region of his head following excessive alcohol consumption. Four years prior, he had undergone anterior cervical discectomy and fusion of C5/6 and a magnetic resonance imaging (MRI) performed 3 years after this surgery indicated that he was suffering from degeneration of C6/7 intervertebral discs. After arriving at the ER, he presented motor impairment at level C7 and lower of manual muscle testing grade 1 as well as moderate loss of physical sensation from the trunk and peripheries of both upper limbs to the peripheries of both lower limbs (Frankel B). Cervical computed tomography (CT) indicated anterior dislocation of C6/7, and MRI indicated severe spinal cord edema. We performed manipulative reduction of C6/7 with the patient under general anesthesia. Next, we performed laminectomy on C5-T1 and posterior fusion on C6/7. Postoperative CT indicated that cervical alignment had improved, and MRI indicated that the spinal cord edema observed prior to surgery had been mitigated. Three months after surgery, motor function and sensory impairment of the lower limbs had improved, and the patient was ambulatory upon discharge from the hospital (Frankel D). In the present case, although C5 and 6 were rigidly fused, degeneration of the C6/7 intervertebral disc occurred and stability was compromised. As a result, even slight trauma placed a severe dynamic burden on the facet joint of C6/7, which led to dislocation.

  6. Cervical facet dislocation adjacent to the fused motion segment

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    Kunio Yokoyama

    2016-01-01

    Full Text Available This study reports on a case that forces re-examination of merits and demerits of anterior cervical fusion. A 79-year-old male was brought to the emergency room (ER of our hospital after he fell and struck the occipital region of his head following excessive alcohol consumption. Four years prior, he had undergone anterior cervical discectomy and fusion of C5/6 and a magnetic resonance imaging (MRI performed 3 years after this surgery indicated that he was suffering from degeneration of C6/7 intervertebral discs. After arriving at the ER, he presented motor impairment at level C7 and lower of manual muscle testing grade 1 as well as moderate loss of physical sensation from the trunk and peripheries of both upper limbs to the peripheries of both lower limbs (Frankel B. Cervical computed tomography (CT indicated anterior dislocation of C6/7, and MRI indicated severe spinal cord edema. We performed manipulative reduction of C6/7 with the patient under general anesthesia. Next, we performed laminectomy on C5-T1 and posterior fusion on C6/7. Postoperative CT indicated that cervical alignment had improved, and MRI indicated that the spinal cord edema observed prior to surgery had been mitigated. Three months after surgery, motor function and sensory impairment of the lower limbs had improved, and the patient was ambulatory upon discharge from the hospital (Frankel D. In the present case, although C5 and 6 were rigidly fused, degeneration of the C6/7 intervertebral disc occurred and stability was compromised. As a result, even slight trauma placed a severe dynamic burden on the facet joint of C6/7, which led to dislocation.

  7. Automatic Scheme for Fused Medical Image Segmentation with Nonsubsampled Contourlet Transform

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    Ch.Hima Bindu

    2012-10-01

    Full Text Available Medical image segmentation has become an essential technique in clinical and research- oriented applications. Because manual segmentation methods are tedious, and semi-automatic segmentation lacks the flexibility, fully-automatic methods have become the preferred type of medical image segmentation. This work proposes a robust fully automatic segmentation scheme based on the modified contouring technique. The entire scheme consists of three stages. In the first stage, the Nonsubsampled Contourlet Transform (NSCT of image is computed. This is followed by the fusion of coefficients using fusion method. For that fused image local threshold is computed. This is followed by the second stage in which the initial points are determined by computation of global threshold. Finally, in the third stage, searching procedure is started from each initial point to obtain closed-loop contours. The whole process is fully automatic. This avoids the disadvantages of semi-automatic schemes such as manually selecting the initial contours and points.

  8. Auxiliary anatomical labels for joint segmentation and atlas registration

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    Gass, Tobias; Szekely, Gabor; Goksel, Orcun

    2014-03-01

    This paper studies improving joint segmentation and registration by introducing auxiliary labels for anatomy that has similar appearance to the target anatomy while not being part of that target. Such auxiliary labels help avoid false positive labelling of non-target anatomy by resolving ambiguity. A known registration of a segmented atlas can help identify where a target segmentation should lie. Conversely, segmentations of anatomy in two images can help them be better registered. Joint segmentation and registration is then a method that can leverage information from both registration and segmentation to help one another. It has received increasing attention recently in the literature. Often, merely a single organ of interest is labelled in the atlas. In the presense of other anatomical structures with similar appearance, this leads to ambiguity in intensity based segmentation; for example, when segmenting individual bones in CT images where other bones share the same intensity profile. To alleviate this problem, we introduce automatic generation of additional labels in atlas segmentations, by marking similar-appearance non-target anatomy with an auxiliary label. Information from the auxiliary-labeled atlas segmentation is then incorporated by using a novel coherence potential, which penalizes differences between the deformed atlas segmentation and the target segmentation estimate. We validated this on a joint segmentation-registration approach that iteratively alternates between registering an atlas and segmenting the target image to find a final anatomical segmentation. The results show that automatic auxiliary labelling outperforms the same approach using a single label atlasses, for both mandibular bone segmentation in 3D-CT and corpus callosum segmentation in 2D-MRI.

  9. Segmentation of foreground apple targets by fusing visual attention mechanism and growth rules of seed points

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    Qu, W.; Shang, W.; Shao, Y.; Wang, D.; Yu, X.; Song, H.

    2015-07-01

    Accurate segmentation of apple targets is one of the most important problems to be solved in the vision system of apple picking robots. This work aimed to solve the difficulties that background targets often bring to foreground targets segmentation, by fusing the visual attention mechanism and the growth rule of seed points. Background targets could be eliminated by extracting the ROI (region of interest) of apple targets; the ROI was roughly segmented on the HSV color space, and then each of the pixels was used as a seed growing point. The growth rule of the seed points was adopted to obtain the whole area of apple targets from seed growing points. The proposed method was tested with 20 images captured in a natural scene, including 54 foreground apple targets and approximately 84 background apple targets. Experimental results showed that the proposed method can remove background targets and focus on foreground targets, while the k-means algorithm and the chromatic aberration algorithm cannot. Additionally, its average segmentation error rate was 13.23%, which is 2.71% higher than that of the k-means algorithm and 2.95% lower than that of the chromatic aberration algorithm. In conclusion, the proposed method contributes to the vision system of apple-picking robots to locate foreground apple targets quickly and accurately under a natural scene. (Author)

  10. Image-driven cardiac left ventricle segmentation for the evaluation of multiview fused real-time 3-dimensional echocardiography images.

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    Rajpoot, Kashif; Noble, J Alison; Grau, Vicente; Szmigielski, Cezary; Becher, Harald

    2009-01-01

    Real-time 3-dimensional echocardiography (RT3DE) permits the acquisition and visualization of the beating heart in 3D. Despite a number of efforts to automate the left ventricle (LV) delineation from RT3DE images, this remains a challenging problem due to the poor nature of the acquired images usually containing missing anatomical information and high speckle noise. Recently, there have been efforts to improve image quality and anatomical definition by acquiring multiple single-view RT3DE images with small probe movements and fusing them together after alignment. In this work, we evaluate the quality of the multiview fused images using an image-driven semiautomatic LV segmentation method. The segmentation method is based on an edge-driven level set framework, where the edges are extracted using a local-phase inspired feature detector for low-contrast echocardiography boundaries. This totally image-driven segmentation method is applied for the evaluation of end-diastolic (ED) and end-systolic (ES) single-view and multiview fused images. Experiments were conducted on 17 cases and the results show that multiview fused images have better image segmentation quality, but large failures were observed on ED (88.2%) and ES (58.8%) single-view images.

  11. Joint Graph Layouts for Visualizing Collections of Segmented Meshes

    KAUST Repository

    Ren, Jing

    2017-09-12

    We present a novel and efficient approach for computing joint graph layouts and then use it to visualize collections of segmented meshes. Our joint graph layout algorithm takes as input the adjacency matrices for a set of graphs along with partial, possibly soft, correspondences between nodes of different graphs. We then use a two stage procedure, where in the first step, we extend spectral graph drawing to include a consistency term so that a collection of graphs can be handled jointly. Our second step extends metric multi-dimensional scaling with stress majorization to the joint layout setting, while using the output of the spectral approach as initialization. Further, we discuss a user interface for exploring a collection of graphs. Finally, we show multiple example visualizations of graphs stemming from collections of segmented meshes and we present qualitative and quantitative comparisons with previous work.

  12. Segmentation and determination of joint space width in foot radiographs

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    Schenk, O.; de Muinck Keizer, D. M.; Bernelot Moens, H. J.; Slump, C. H.

    2016-03-01

    Joint damage in rheumatoid arthritis is frequently assessed using radiographs of hands and feet. Evaluation includes measurements of the joint space width (JSW) and detection of erosions. Current visual scoring methods are timeconsuming and subject to inter- and intra-observer variability. Automated measurement methods avoid these limitations and have been fairly successful in hand radiographs. This contribution aims at foot radiographs. Starting from an earlier proposed automated segmentation method we have developed a novel model based image analysis algorithm for JSW measurements. This method uses active appearance and active shape models to identify individual bones. The model compiles ten submodels, each representing a specific bone of the foot (metatarsals 1-5, proximal phalanges 1-5). We have performed segmentation experiments using 24 foot radiographs, randomly selected from a large database from the rheumatology department of a local hospital: 10 for training and 14 for testing. Segmentation was considered successful if the joint locations are correctly determined. Segmentation was successful in only 14%. To improve results a step-by-step analysis will be performed. We performed JSW measurements on 14 randomly selected radiographs. JSW was successfully measured in 75%, mean and standard deviation are 2.30+/-0.36mm. This is a first step towards automated determination of progression of RA and therapy response in feet using radiographs.

  13. Influence of the stability of a fused protein and its distance to the amyloidogenic segment on fibril formation.

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    Anja Buttstedt

    Full Text Available Conversion of native proteins into amyloid fibrils is irreversible and therefore it is difficult to study the interdependence of conformational stability and fibrillation by thermodynamic analyses. Here we approached this problem by fusing amyloidogenic poly-alanine segments derived from the N-terminal domain of the nuclear poly (A binding protein PABPN1 with a well studied, reversibly unfolding protein, CspB from Bacillus subtilis. Earlier studies had indicated that CspB could maintain its folded structure in fibrils, when it was separated from the amyloidogenic segment by a long linker. When CspB is directly fused with the amyloidogenic segment, it unfolds because its N-terminal chain region becomes integrated into the fibrillar core, as shown by protease mapping experiments. Spacers of either 3 or 16 residues between CspB and the amyloidogenic segment were not sufficient to prevent this loss of CspB structure. Since the low thermodynamic stability of CspB (ΔG(D = 12.4 kJ/mol might be responsible for unfolding and integration of CspB into fibrils, fusions with a CspB mutant with enhanced thermodynamic stability (ΔG(D = 26.9 kJ/mol were studied. This strongly stabilized CspB remained folded and prevented fibril formation in all fusions. Our data show that the conformational stability of a linked, independently structured protein domain can control fibril formation.

  14. Automatic Scheme for Fused Medical Image Segmentation with Nonsubsampled Contourlet Transform

    OpenAIRE

    Ch.Hima Bindu; Dr. K. Satya Prasad

    2012-01-01

    Medical image segmentation has become an essential technique in clinical and research- oriented applications. Because manual segmentation methods are tedious, and semi-automatic segmentation lacks the flexibility, fully-automatic methods have become the preferred type of medical image segmentation. This work proposes a robust fully automatic segmentation scheme based on the modified contouring technique. The entire scheme consists of three stages. In the first stage, the Nonsubsampled Contour...

  15. Analysis of postmarket complaints database for the iFuse SI Joint Fusion System®: a minimally invasive treatment for degenerative sacroiliitis and sacroiliac joint disruption

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    Miller LE

    2013-05-01

    Full Text Available Larry E Miller,1,2 W Carlton Reckling,3 Jon E Block21Miller Scientific Consulting Inc, Arden, NC, 2The Jon Block Group, San Francisco, CA, 3SI-BONE Inc, San Jose, CA, USABackground: The sacroiliac joint is a common but under-recognized source of low back and gluteal pain. Patients with degenerative sacroiliitis or sacroiliac joint disruption resistant to nonsurgical treatments may undergo open surgery with sacroiliac joint arthrodesis, although outcomes are mixed and risks are significant. Minimally invasive sacroiliac joint arthrodesis was developed to minimize the risk of iatrogenic injury and to improve patient outcomes compared with open surgery.Methods: Between April 2009 and January 2013, 5319 patients were treated with the iFuse SI Joint Fusion System® for conditions including sacroiliac joint disruption and degenerative sacroiliitis. A database was prospectively developed to record all complaints reported to the manufacturer in patients treated with the iFuse device. Complaints were collected through spontaneous reporting mechanisms in support of ongoing mandatory postmarket surveillance efforts.Results: Complaints were reported in 204 (3.8% patients treated with the iFuse system. Pain was the most commonly reported clinical complaint (n = 119, 2.2%, with nerve impingement (n = 48, 0.9% and recurrent sacroiliac joint pain (n = 43, 0.8% most frequently cited. All other clinical complaints were rare (≤0.2%. Ninety-six revision surgeries were performed in 94 (1.8% patients at a median follow-up of four (range 0–30 months. Revisions were typically performed in the early postoperative period for treatment of a symptomatic malpositioned implant (n = 46, 0.9% or to correct an improperly sized implant in an asymptomatic patient (n = 10, 0.2%. Revisions in the late postoperative period were performed to treat symptom recurrence (n = 34, 0.6% or for continued pain of undetermined etiology (n = 6, 0.1%.Conclusion: Analysis of a postmarket

  16. Joint Image Reconstruction and Segmentation Using the Potts Model

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    Storath, Martin; Frikel, Jürgen; Unser, Michael

    2014-01-01

    We propose a new algorithmic approach to the non-smooth and non-convex Potts problem (also called piecewise-constant Mumford-Shah problem) for inverse imaging problems. We derive a suitable splitting into specific subproblems that can all be solved efficiently. Our method does not require a priori knowledge on the gray levels nor on the number of segments of the reconstruction. Further, it avoids anisotropic artifacts such as geometric staircasing. We demonstrate the suitability of our method for joint image reconstruction and segmentation from limited data in x-ray and photoacoustic tomography. For instance, our method is able to reconstruct the Shepp-Logan phantom from $7$ angular views only. We demonstrate the practical applicability in an experiment with real PET data.

  17. Fusion angle affects intervertebral adjacent spinal segment joint forces-Model-based analysis of patient specific alignment.

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    Senteler, Marco; Weisse, Bernhard; Rothenfluh, Dominique A; Farshad, Mazda T; Snedeker, Jess G

    2017-01-01

    This study addresses the hypothesis that adjacent segment intervertebral joint loads are sensitive to the degree of lordosis that is surgically imposed during vertebral fusion. Adjacent segment degeneration is often observed after lumbar fusion, but a causative mechanism is not yet clearly evident. Altered kinematics of the adjacent segments and potentially nonphysiological mechanical joint loads have been implicated in this process. However, little is known of how altered alignment and kinematics influence loading of the adjacent intervertebral joints under consideration of active muscle forces. This study investigated these effects by simulating L4/5 fusions using kinematics-driven musculoskeletal models of one generic and eight sagittal alignment-specific models. Models featured different spinopelvic configurations but were normalized by body height, masses, and muscle properties. Fusion of the L4/5 segment was implemented in an in situ (22°), hyperlordotic (32°), and hypolordotic (8°) fashion and kinematic input parameters were changed accordingly based on findings of an in vitro investigation. Bending motion from upright standing to 45° forward flexion and back was simulated for all models in intact and fused conditions. Joint loads at adjacent levels and moment arms of spinal muscles experienced changes after all types of fusion. Hypolordotic configuration led to an increase of adjacent segment (L3/4) shear forces of 29% on average, whereas hyperlordotic fusion reduced shear by 39%. Overall, L4/5 in situ fusion resulted in intervertebral joint forces closest to intact loading conditions. An artificial decrease in lumbar lordosis (minus 14° on average) caused by an L4/5 fusion lead to adverse loading conditions, particularly at the cranial adjacent levels, and altered muscle moment arms, in particular for muscles in the vicinity of the fusion. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:131-139, 2017.

  18. Disc height and anteroposterior translation in fused and adjacent segments after lumbar spine fusion

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    Frobin, Wolfgang

    2003-09-01

    Full Text Available In a series of 46 patients the effects of spinal fusion upon intervertebral height and sagittal alignment in operated and non-operated segments were retrospectively evaluated on digitized radiographs. Data was compared with age- and gender-normalized standard values. The objective was to evaluate the influence of different types of spine fusions primarily upon adjacent segments, particularly in terms of degeneration and sagittal profile of the lumbar spine. Incidence of adjacent segment degeneration (ASD is still highly controversial. However, not every degeneration adjacent to spinal fusion must be caused by the fusion and responsibility of the fusion for ASD may vary with its range and type. Distortion Corrected Roentgen Analysis (DCRA was utilized. DCRA is a proven valid, reliable, observer-independent, and accurate tool for assessment of these parameters over time and in comparison with "normal" cohorts. With this method the exact posture of the patients needs not to be known.There was little evidence for serious fusion-related ASD within an average of 40 months follow-up. No difference could be detected for rigid vs. non-rigid fusion and instrumented vs. non-instrumented techniques. Temporary postoperative distraction effects could be detected in operated and non-operated segments. Absolute preoperative values for intervertebral height and vertebral slip were age-related. Retrospectively, the choice of segments for fusion was clearly based upon radiological criteria. Thus we conclude that radiological parameters have an obvious clinical relevance for decision-making and need to be quantified. Within the limitations of this pilot study, true fusion related ASD seems to be infrequent.

  19. Implant survivorship analysis after minimally invasive sacroiliac joint fusion using the iFuse Implant System®

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    Cher DJ

    2015-11-01

    Full Text Available Daniel J Cher,1 W Carlton Reckling,2 Robyn A Capobianco1 1Department of Clinical Affairs, SI-BONE, Inc., 2Department of Medical Affairs, SI-BONE, Inc., San Jose, CA, USA Introduction: Surgical revision rate is a key outcome with all permanent implants. The iFuse Implant System® is a permanent implant used to perform minimally invasive sacroiliac joint fusion. The purpose of this study is to determine the surgical revision rate after sacroiliac joint fusion surgery with this system. Methods: Using two internal sources of information, revision surgeries were identified and linked to index surgeries. The likelihood of revision surgery was calculated using the Kaplan–Meier life table approach. Predictors of revision were explored. Results: Four-year survivorship free from implant revision was 96.46%. Revision rate did not differ by sex and was lower for age >65. In all, 24% of revisions occurred within the first 30 days after surgery; 63.5% occurred within year 1. Implant survivorship has improved annually since the device was introduced in 2009. Conclusion: The survivorship rate with this implant is high and improving; the rate is somewhat higher than total hip replacement but lower than that of lumbar spine procedures. Keywords: safety, sacroiliac joint fusion, iFuse Implant System, revision

  20. Uni-modal versus joint segmentation for region-based image fusion

    NARCIS (Netherlands)

    Lewis, J.J.; Nikolov, S.G.; Canagarajah, C.N.; Bull, D.R.; Toet, A.

    2006-01-01

    A number of segmentation techniques are compared with regard to their usefulness for region-based image and video fusion. In order to achieve this, a new multi-sensor data set is introduced containing a variety of infra-red, visible and pixel fused images together with manually produced 'ground

  1. Uni-modal versus joint segmentation for region-based image fusion

    NARCIS (Netherlands)

    Lewis, J.J.; Nikolov, S.G.; Canagarajah, C.N.; Bull, D.R.; Toet, A.

    2006-01-01

    A number of segmentation techniques are compared with regard to their usefulness for region-based image and video fusion. In order to achieve this, a new multi-sensor data set is introduced containing a variety of infra-red, visible and pixel fused images together with manually produced 'ground trut

  2. The posterior segment of the temporomandibular joint capsule and its anatomic relationship.

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    Mérida-Velasco, J Ramón; Rodríguez, J Francisco; de la Cuadra, Crótida; Peces, M Dolores; Mérida, J Antonio; Sánchez, Indalecio

    2007-01-01

    The aim of this work was to clarify the arrangement of the posterior segment of the temporomandibular joint capsule and its pertinent relationships. The temporomandibular region was dissected bilaterally in 20 adult cadavers. Natural stained latex was injected into 16 cadavers through the external carotid artery to facilitate the dissection of the arterial vessels. The posterior segment of the joint capsule is made up of the so-called "bilaminar zone" of the articular disc. The upper internal portion of the posterior segment of the capsule was reinforced by the discomalleolar ligament. The retroarticular space was filled with loose connective tissue and the anterior branches of the anterior tympanic artery were distributed throughout the posterior segment of the joint capsule. The posterior segment of the temporomandibular joint capsule corresponds to the bilaminar zone of the articular disc. The structures of the retroarticular space are extracapsular.

  3. Significant relationship between local angle at fused segments and C2-7 angle: Average duration of longer than 20 years after anterior cervical discectomy and fusion

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    T Nagata

    2011-01-01

    Full Text Available Background : The authors have focused their attention to the radiological durability of cervical sagittal alignment after anterior cervical discectomy and fusion (ACDF using autologous bone grafting. Materials and Methods : Among the patients who underwent ACDF with trans-unco-discal (TUD approach between 1976 and 1997, 22 patients (16 males and 6 females made return visits for a clinical evaluation. Patients with trauma or previously treated by anterior cervical fusion or by posterior decompression were excluded from the present study. Clinical evaluation included adjacent segment degeneration (ASD, osseous fusion, local angle at the fused segments and C2-7 angle of cervical spine. Results : The duration after ACDF ranged from 13 to 34 years with an average of 21.3 ± 7.0 years. A single level fusion was done on 8 patients, 2 levels on 11 patients, 3 levels on 2 patients, and 4 levels on 1 patient. Imaging studies indicated that 12 of the 22 patients (54.5% were graded as having symptomatic ASD. Osseous bony fusion at ACDF was recognized in all cases. None of the patients demonstrated kyphotic malalignment of the cervical spine. Average degrees of local angle at the fused segments and the C2-7 angle were 7.06 and 17.6, respectively. Statistical analysis indicated a significant relationship between the local at the fused segments and C2-7 angles. Conclusions : Sagittal alignment of the cervical spine was durable long after ACDF when the local angle at the fused segments was well stabilized.

  4. A Variational Framework for Joint Detection and Segmentation of Ovarian Cancer Metastases

    OpenAIRE

    Liu, Jianfei; Wang, Shijun; Linguraru, Marius George; Yao, Jianhua; Summers, Ronald M.

    2013-01-01

    Detection and segmentation of ovarian cancer metastases have great clinical impacts on women’s health. However, the random distribution and weak boundaries of metastases significantly complicate this task. This paper presents a variational framework that combines region competition based level set propagation and image matching flow computation to jointly detect and segment metastases. Image matching flow not only detects metastases, but also creates shape priors to reduce over-segmentation. ...

  5. Anterior and posterior centers jointly regulate Bombyx embryo body segmentation.

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    Nakao, Hajime

    2012-11-15

    Insect embryo segmentation is largely divided into long and short germ types. In the long germ type, each segment primordium is represented on a large embryonic rudiment of the blastoderm, and segmental patterning occurs nearly simultaneously in the syncytium. In the short germ type, however, only anterior segments are represented in the small embryonic rudiment, usually located on the egg posterior, and the rest of the segments are added sequentially from the posterior growth zone in a cellular context. The long germ type is thought to have evolved from the short germ type. It is proposed that this transition, which appears to have occurred multiple times over the course of evolution, was realized through the acquisition of a localized anterior instruction center. Here, I examined the early segmentation process in the silkmoth Bombyx mori, a lepidopteran insect, in which the mechanisms of anterior-posterior (AP) axis formation have not been well analyzed. In this insect, both the long germ and short germ features have been reported. The mRNAs for two key genes involved in insect AP axis formation, orthodenticle (Bm-otd) and caudal (Bm-cad), are localized maternally in the germ anlage, where they act as anterior and posterior instruction centers, respectively. RNAi studies indicate that, while Bm-cad affects the formation of all the even skipped (Bm-eve) stripes, there is also anterior Bm-eve stripe formation activity that involves Bm-otd. Thus, there is redundancy in Bm-eve stripe formation activity that must be coordinated. Some genetic interactions, identified either experimentally or hypothetically, are also introduced, which might enable robust AP formation in this organism.

  6. Model-based 3D segmentation of the bones of joints in medical images

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    Liu, Jiamin; Udupa, Jayaram K.; Saha, Punam K.; Odhner, Dewey; Hirsch, Bruce E.; Siegler, Sorin; Simon, Scott; Winkelstein, Beth A.

    2005-04-01

    There are several medical application areas that require the segmentation and separation of the component bones of joints in a sequence of acquired images of the joint under various loading conditions, our own target area being joint motion analysis. This is a challenging problem due to the proximity of bones at the joint, partial volume effects, and other imaging modality-specific factors that confound boundary contrast. A model-based strategy is proposed in this paper wherein a rigid model of the bone is generated from a segmentation of the bone in the image corresponding to one position of the joint by using the live wire method. In other images of the joint, this model is used to search for the same bone by minimizing an energy functional that utilizes both boundary- and region-based information. An evaluation of the method by utilizing a total of 60 data sets on MR and CT images of the ankle complex and cervical spine indicates that the segmentations agree very closely with the live wire segmentations yielding true positive and false positive volume fractions in the range 89-97% and 0.2-0.7%. The method requires 1-2 minutes of operator time and 6-7 minutes of computer time, which makes it significantly more efficient than live wire - the only method currently available for the task.

  7. Joint graph cut and relative fuzzy connectedness image segmentation algorithm.

    Science.gov (United States)

    Ciesielski, Krzysztof Chris; Miranda, Paulo A V; Falcão, Alexandre X; Udupa, Jayaram K

    2013-12-01

    We introduce an image segmentation algorithm, called GC(sum)(max), which combines, in novel manner, the strengths of two popular algorithms: Relative Fuzzy Connectedness (RFC) and (standard) Graph Cut (GC). We show, both theoretically and experimentally, that GC(sum)(max) preserves robustness of RFC with respect to the seed choice (thus, avoiding "shrinking problem" of GC), while keeping GC's stronger control over the problem of "leaking though poorly defined boundary segments." The analysis of GC(sum)(max) is greatly facilitated by our recent theoretical results that RFC can be described within the framework of Generalized GC (GGC) segmentation algorithms. In our implementation of GC(sum)(max) we use, as a subroutine, a version of RFC algorithm (based on Image Forest Transform) that runs (provably) in linear time with respect to the image size. This results in GC(sum)(max) running in a time close to linear. Experimental comparison of GC(sum)(max) to GC, an iterative version of RFC (IRFC), and power watershed (PW), based on a variety medical and non-medical images, indicates superior accuracy performance of GC(sum)(max) over these other methods, resulting in a rank ordering of GC(sum)(max)>PW∼IRFC>GC.

  8. MRI Slice Segmentation and 3D Modelling of Temporomandibular Joint Measured by Microscopic Coil

    Science.gov (United States)

    Smirg, O.; Liberda, O.; Smekal, Z.; Sprlakova-Pukova, A.

    2012-01-01

    The paper focuses on the segmentation of magnetic resonance imaging (MRI) slices and 3D modelling of the temporomandibular joint disc in order to help physicians diagnose patients with dysfunction of the temporomandibular joint (TMJ). The TMJ is one of the most complex joints in the human body. The most common joint dysfunction is due to the disc. The disc is a soft tissue, which in principle cannot be diagnosed by the CT method. Therefore, a 3D model is made from the MRI slices, which can image soft tissues. For the segmentation of the disc in individual slices a new method is developed based on spatial distribution and anatomical TMJ structure with automatic thresholding. The thresholding is controlled by a genetic algorithm. The 3D model is realized using the marching cube method.

  9. A variational framework for joint detection and segmentation of ovarian cancer metastases.

    Science.gov (United States)

    Liu, Jianfei; Wang, Shijun; Linguraru, Marius George; Yao, Jianhua; Summers, Ronald M

    2013-01-01

    Detection and segmentation of ovarian cancer metastases have great clinical impacts on women's health. However, the random distribution and weak boundaries of metastases significantly complicate this task. This paper presents a variational framework that combines region competition based level set propagation and image matching flow computation to jointly detect and segment metastases. Image matching flow not only detects metastases, but also creates shape priors to reduce over-segmentation. Accordingly, accurate segmentation helps to improve the detection accuracy by separating flow computation in metastasis and non-metastasis regions. Since all components in the image processing pipeline benefit from each other, our joint framework can achieve accurate metastasis detection and segmentation. Validation on 50 patient datasets demonstrated that our joint approach was superior to a sequential method with sensitivity 89.2% vs. 81.4% (Fisher exact test p = 0.046) and false positive per patient 1.04 vs. 2.04. The Dice coefficient of metastasis segmentation was 92 +/- 5.2% vs. 72 +/- 8% (paired t-test p = 0.022), and the average surface distance was 1.9 +/- 1.5mm vs. 4.5 +/- 2.2mm (paired t-test p = 0.004).

  10. Load Rate of Facet Joints at the Adjacent Segment Increased After Fusion

    Directory of Open Access Journals (Sweden)

    Hui Li

    2015-01-01

    Full Text Available Background: The cause of the adjacent segment degeneration (ASD after fusion remains unknown. It is reported that adjacent facet joint stresses increase after anterior cervical discectomy and fusion. This increase of stress rate may lead to tissue injury. Thus far, the load rate of the adjacent segment facet joint after fusion remains unclear. Methods: Six C2-C7 cadaveric spine specimens were loaded under four motion modes: Flexion, extension, rotation, and lateral bending, with a pure moment using a 6° robot arm combined with an optical motion analysis system. The Tecscan pressure test system was used for testing facet joint pressure. Results: The contact mode of the facet joints and distributions of the force center during different motions were recorded. The adjacent segment facet joint forces increased faster after fusion, compared with intact conditions. While the magnitude of pressures increased, there was no difference in distribution modes before and after fusion. No pressures were detected during flexion. The average growth velocity during extension was the fastest and was significantly faster than lateral bending. Conclusions: One of the reasons for cartilage injury was the increasing stress rate of loading. This implies that ASD after fusion may be related to habitual movement before and after fusion. More and faster extension is disadvantageous for the facet joints and should be reduced as much as possible.

  11. Load Rate of Facet Joints at the Adjacent Segment Increased After Fusion

    Institute of Scientific and Technical Information of China (English)

    Hui Li; Bao-Qing Pei; Jin-Cai Yang; Yong Hai; De-Yu Li; Shu-Qin Wu

    2015-01-01

    Background:The cause of the adjacent segment degeneration (ASD) after fusion remains unknown.It is reported that adjacent facet joint stresses increase after anterior cervical discectomy and fusion.This increase of stress rate may lead to tissue injury.Thus far,the load rate of the adjacent segment facet joint after fusion remains unclear.Methods:Six C2-C7 cadaveric spine specimens were loaded under four motion modes:Flexion,extension,rotation,and lateral bending,with a pure moment using a 6° robot arm combined with an optical motion analysis system.The Tecscan pressure test system was used for testing facet joint pressure.Results:The contact mode of the facet joints and distributions of the force center during different motions were recorded.The adjacent segment facet joint forces increased faster after fusion,compared with intact conditions.While the magnitude of pressures increased,there was no difference in distribution modes before and after fusion.No pressures were detected during flexion.The average growth velocity during extension was the fastest and was significantly faster than lateral bending.Conclusions:One of the reasons for cartilage injury was the increasing stress rate of loading.This implies that ASD after fusion may be related to habitual movement before and after fusion.More and faster extension is disadvantageous for the facet joints and should be reduced as much as possible.

  12. Local dynamic stability of the trunk segments and lower extremity joints during backward walking.

    Science.gov (United States)

    Wu, Yu; Xiao, Fei; Gu, Dong-Yun

    2015-01-01

    Backward walking has become a popular training method in physical exercise and clinical rehabilitation. For the sake of safety, it is important to keep a stable gait during backward walking. However, the gait stability during backward walking was rarely studied. This study investigated the effects of walking direction on local dynamic stability of the trunk segments (neck, torso and pelvis) and lower extremity joints (hip, knee and ankle joint). The maximum Lyapunov exponents (λ(s)) of 17 young healthy male adults were calculated while they were walking under three conditions: backward walking with preferred walking speed (BW), forward walking (FW) with the same speed determined by BW, and forward walking with normal speed (FWN). We found that compared with FW, BW showed significant higher values of λ(s) in the trunk segments in vertical (VT) direction (psegment also displayed a higher value of λ(s) in anterior-posterior (AP) direction (pwalking speed was found between FW and FWN condition in VT direction (pwalking did impair the local dynamic stability in trunk segments and lower extremity joints. Especially, the negative effect of BW on the poor gait stability in the AP direction of torso segment, and AB/AD and RT motion of knee joint should not be neglected.

  13. A comparison between joint coordinate system and attitude vector for multi-segment foot kinematics.

    Science.gov (United States)

    Rouhani, H; Favre, J; Crevoisier, X; Jolles, B M; Aminian, K

    2012-07-26

    The joint angles of multi-segment foot models have been primarily described using two mathematical methods: the joint coordinate system and the attitude vector. This study aimed to determine whether the angles obtained through these two descriptors are comparable, and whether these descriptors have similar sensitivity to experimental errors. Six subjects walked eight times on an instrumented walkway while the joint angles among shank, hindfoot, medial forefoot, and lateral forefoot were measured. The angles obtained using both descriptors and their sensitivity to experimental errors were compared. There was no overall significant difference between the ranges of motion obtained using both descriptors. However, median differences of more than 6° were noticed for the medial-lateral forefoot joint. For all joints and rotation planes, both descriptors provided highly similar angle patterns (median correlation coefficient: R>0.90), except for the medial-lateral forefoot angle in the transverse plane (median R=0.77). The joint coordinate system was significantly more sensitive to anatomical landmarks misplacement errors. However, the absolute differences of sensitivity were small relative to the joints ranges of motion. In conclusion, the angles obtained using these two descriptors were not identical, but were similar for at least the shank-hindfoot and hindfoot-medial forefoot joints. Therefore, the angle comparison across descriptors is possible for these two joints. Comparison should be done more carefully for the medial-lateral forefoot joint. Moreover, despite different sensitivities to experimental errors, the effects of the experimental errors on the angles were small for both descriptors suggesting that both descriptors can be considered for multi-segment foot models.

  14. Modeling and analysis of passive dynamic bipedal walking with segmented feet and compliant joints

    Science.gov (United States)

    Huang, Yan; Wang, Qi-Ning; Gao, Yue; Xie, Guang-Ming

    2012-10-01

    Passive dynamic walking has been developed as a possible explanation for the efficiency of the human gait. This paper presents a passive dynamic walking model with segmented feet, which makes the bipedal walking gait more close to natural human-like gait. The proposed model extends the simplest walking model with the addition of flat feet and torsional spring based compliance on ankle joints and toe joints, to achieve stable walking on a slope driven by gravity. The push-off phase includes foot rotations around the toe joint and around the toe tip, which shows a great resemblance to human normal walking. This paper investigates the effects of the segmented foot structure on bipedal walking in simulations. The model achieves satisfactory walking results on even or uneven slopes.

  15. Modeling and analysis of passive dynamic bipedal walking with segmented feet and compliant joints

    Institute of Scientific and Technical Information of China (English)

    Yan Huang; Qi-Ning Wang; Yue Gao; Guang-Ming Xie

    2012-01-01

    Passive dynamic walking has been developed as a possible explanation for the efficiency of the human gait.This paper presents a passive dynamic walking model with segmented feet,which makes the bipedal walking gait more close to natural human-like gait.The proposed model extends the simplest walking model with the addition of flat feet and torsional spring based compliance on ankle joints and toe joints,to achieve stable walking on a slope driven by gravity.The push-off phase includes foot rotations around the toe joint and around the toe tip,which shows a great resemblance to human normal walking.This paper investigates the effects of the segmented foot structure on bipedal walking in simulations. The model achieves satisfactory walking results on even or uneven slopes.

  16. Measurement of multi-segment foot joint angles during gait using a wearable system.

    Science.gov (United States)

    Rouhani, Hossein; Favre, Julien; Crevoisier, Xavier; Aminian, Kamiar

    2012-06-01

    Usually the measurement of multi-segment foot and ankle complex kinematics is done with stationary motion capture devices which are limited to use in a gait laboratory. This study aimed to propose and validate a wearable system to measure the foot and ankle complex joint angles during gait in daily conditions, and then to investigate its suitability for clinical evaluations. The foot and ankle complex consisted of four segments (shank, hindfoot, forefoot, and toes), with an inertial measurement unit (3D gyroscopes and 3D accelerometers) attached to each segment. The angles between the four segments were calculated in the sagittal, coronal, and transverse planes using a new algorithm combining strap-down integration and detection of low-acceleration instants. To validate the joint angles measured by the wearable system, three subjects walked on a treadmill for five minutes at three different speeds. A camera-based stationary system that used a cluster of markers on each segment was used as a reference. To test the suitability of the system for clinical evaluation, the joint angle ranges were compared between a group of 10 healthy subjects and a group of 12 patients with ankle osteoarthritis, during two 50-m walking trials where the wearable system was attached to each subject. On average, over all joints and walking speeds, the RMS differences and correlation coefficients between the angular curves obtained using the wearable system and the stationary system were 1 deg and 0.93, respectively. Moreover, this system was able to detect significant alteration of foot and ankle function between the group of patients with ankle osteoarthritis and the group of healthy subjects. In conclusion, this wearable system was accurate and suitable for clinical evaluation when used to measure the multi-segment foot and ankle complex kinematics during long-distance walks in daily life conditions.

  17. The effect of variability in body segment parameters on joint moment using Monte Carlo simulations.

    Science.gov (United States)

    Nguyen, Tam C; Reynolds, Karen J

    2014-01-01

    This study used Monte Carlo methods to simulate the effects of variability and uncertainty in inertial body segment parameters (BSPs) on joint torques calculated using inverse dynamics. The average and standard deviation values of BSPs from previously published studies were used as inputs into the Monte Carlo simulation. Data from five groups were evaluated: cadaveric subjects; living subjects (Caucasian only); female living subjects (Caucasian only); male living subjects (Caucasian only); and living subjects (non-Caucasian). The differences in BSPs observed between the different groups were statistically significant; however, using BSP variability data from these groups made little difference to the calculated joint torques. This suggests that for slow and repeatable movement such as walking, BSPs have little effect on joint moments, except for the swing phase. Even then, the magnitude of difference in the swing phase due to variability in BSPs is not much greater than the inter-trial variability. As expected, distal BSPs have little effect on proximal joint moment.

  18. Segmentation of joint and musculoskeletal tissue in the study of arthritis.

    Science.gov (United States)

    Pedoia, Valentina; Majumdar, Sharmila; Link, Thomas M

    2016-04-01

    As the most frequent cause of physical disability, musculoskeletal diseases such as arthritis and osteoporosis have a great social and economical impact. Quantitative magnetic resonance imaging (MRI) biomarkers are important tools that allow clinicians to better characterize, monitor, and even predict musculoskeletal disease progression. Post-processing pipelines often include image segmentation. Manually identifying the border of the region of interest (ROI) is a difficult and time-consuming task. Manual segmentation is also affected by inter- and intrauser variability, thus limiting standardization. Fully automatic or semi-automatic methods that minimize the user interaction are highly desirable. Unfortunately, an ultimate, highly reliable and extensively evaluated solution for joint and musculoskeletal tissue segmentation has not yet been proposed, and many clinical studies still adopt fully manual procedures. Moreover, the clinical translation of several promising quantitative MRI techniques is highly affected by the lack of an established, fast, and accurate segmentation method. The goal of this review is to present some of the techniques proposed in recent literature that have been adopted in clinical studies for joint and musculoskeletal tissue analyses in arthritis patients. The most widely used MRI sequences and image processing algorithms employed to accomplish segmentation challenges will be discussed in this paper.

  19. Comparative analysis of methods for estimating arm segment parameters and joint torques from inverse dynamics.

    Science.gov (United States)

    Piovesan, Davide; Pierobon, Alberto; Dizio, Paul; Lackner, James R

    2011-03-01

    A common problem in the analyses of upper limb unfettered reaching movements is the estimation of joint torques using inverse dynamics. The inaccuracy in the estimation of joint torques can be caused by the inaccuracy in the acquisition of kinematic variables, body segment parameters (BSPs), and approximation in the biomechanical models. The effect of uncertainty in the estimation of body segment parameters can be especially important in the analysis of movements with high acceleration. A sensitivity analysis was performed to assess the relevance of different sources of inaccuracy in inverse dynamics analysis of a planar arm movement. Eight regression models and one water immersion method for the estimation of BSPs were used to quantify the influence of inertial models on the calculation of joint torques during numerical analysis of unfettered forward arm reaching movements. Thirteen subjects performed 72 forward planar reaches between two targets located on the horizontal plane and aligned with the median plane. Using a planar, double link model for the arm with a floating shoulder, we calculated the normalized joint torque peak and a normalized root mean square (rms) of torque at the shoulder and elbow joints. Statistical analyses quantified the influence of different BSP models on the kinetic variable variance for given uncertainty on the estimation of joint kinematics and biomechanical modeling errors. Our analysis revealed that the choice of BSP estimation method had a particular influence on the normalized rms of joint torques. Moreover, the normalization of kinetic variables to BSPs for a comparison among subjects showed that the interaction between the BSP estimation method and the subject specific somatotype and movement kinematics was a significant source of variance in the kinetic variables. The normalized joint torque peak and the normalized root mean square of joint torque represented valuable parameters to compare the effect of BSP estimation methods

  20. A wrapper-based strategy to jointly combine remote sensing image segmentation and object detection

    Science.gov (United States)

    Wang, Jun; Xie, Baoguo; Zhang, Meng; Yin, Wenjun; Du, Hui; Tang, Yujia

    2017-04-01

    Geospatial Object-Based Image Analysis (GEOBIA) has emerged as a new paradigm for remote sensing image classification and interpretation over the last two decades. However, due to the different sensor spatial characteristics, image timing, viewing geometry, etc., the object-based assumption was challenged across a whole scene when dealing with those targets with highly heterogeneous internal characteristics. In this paper we go one step further and address the problem of object detection using a wrapper-based strategy to jointly combine image segmentation and object detection. It offers an insight into full exploitation of the available remotely sensed data. Object detection and image interpretation not only rely on information from raw images, but also depend on knowledge of the target even knowledge from the outside world beyond the image. Regarding this issue, we used high-level object constraint knowledge to refine the image segmentation, going beyond bottom-up models and considering higher order cliques behind the image contexts. As segmentation helps recognition and recognized or delineated objects constrain segmentation, meanwhile, the "correct" segmentation is somehow a compromise between Top-Down & Bottom-Up segmentation. The framework of the proposed approach suggested that the high resolution satellite image was preprocessed, and then the wrapper-based strategy that jointly combined image segmentation and object detection was conducted to represent and interpreted the total scene. In fact, if image objects are badly constructed, objects cannot be accurately identified and recognized. The key idea of this study is to adopt the wrapper-based strategy for remote sensing image analysis, which enables hierarchically representation and recognition of remote sensing images. This kind of representation is determined by the physical properties of the geospatial objects and implemented based on the multi-scale scheme of real world geospatial objects. The method

  1. Joint infrared target recognition and segmentation using a shape manifold-aware level set.

    Science.gov (United States)

    Yu, Liangjiang; Fan, Guoliang; Gong, Jiulu; Havlicek, Joseph P

    2015-04-29

    We propose new techniques for joint recognition, segmentation and pose estimation of infrared (IR) targets. The problem is formulated in a probabilistic level set framework where a shape constrained generative model is used to provide a multi-class and multi-view shape prior and where the shape model involves a couplet of view and identity manifolds (CVIM). A level set energy function is then iteratively optimized under the shape constraints provided by the CVIM. Since both the view and identity variables are expressed explicitly in the objective function, this approach naturally accomplishes recognition, segmentation and pose estimation as joint products of the optimization process. For realistic target chips, we solve the resulting multi-modal optimization problem by adopting a particle swarm optimization (PSO) algorithm and then improve the computational efficiency by implementing a gradient-boosted PSO (GB-PSO). Evaluation was performed using the Military Sensing Information Analysis Center (SENSIAC) ATR database, and experimental results show that both of the PSO algorithms reduce the cost of shape matching during CVIM-based shape inference. Particularly, GB-PSO outperforms other recent ATR algorithms, which require intensive shape matching, either explicitly (with pre-segmentation) or implicitly (without pre-segmentation).

  2. Joint Infrared Target Recognition and Segmentation Using a Shape Manifold-Aware Level Set

    Directory of Open Access Journals (Sweden)

    Liangjiang Yu

    2015-04-01

    Full Text Available We propose new techniques for joint recognition, segmentation and pose estimation of infrared (IR targets. The problem is formulated in a probabilistic level set framework where a shape constrained generative model is used to provide a multi-class and multi-view shape prior and where the shape model involves a couplet of view and identity manifolds (CVIM. A level set energy function is then iteratively optimized under the shape constraints provided by the CVIM. Since both the view and identity variables are expressed explicitly in the objective function, this approach naturally accomplishes recognition, segmentation and pose estimation as joint products of the optimization process. For realistic target chips, we solve the resulting multi-modal optimization problem by adopting a particle swarm optimization (PSO algorithm and then improve the computational efficiency by implementing a gradient-boosted PSO (GB-PSO. Evaluation was performed using the Military Sensing Information Analysis Center (SENSIAC ATR database, and experimental results show that both of the PSO algorithms reduce the cost of shape matching during CVIM-based shape inference. Particularly, GB-PSO outperforms other recent ATR algorithms, which require intensive shape matching, either explicitly (with pre-segmentation or implicitly (without pre-segmentation.

  3. Preliminary results of automated removal of degenerative joint disease in bone scan lesion segmentation

    Science.gov (United States)

    Chu, Gregory H.; Lo, Pechin; Kim, Hyun J.; Auerbach, Martin; Goldin, Jonathan; Henkel, Keith; Banola, Ashley; Morris, Darren; Coy, Heidi; Brown, Matthew S.

    2013-03-01

    Whole-body bone scintigraphy (or bone scan) is a highly sensitive method for visualizing bone metastases and is the accepted standard imaging modality for detection of metastases and assessment of treatment outcomes. The development of a quantitative biomarker using computer-aided detection on bone scans for treatment response assessment may have a significant impact on the evaluation of novel oncologic drugs directed at bone metastases. One of the challenges to lesion segmentation on bone scans is the non-specificity of the radiotracer, manifesting as high activity related to non-malignant processes like degenerative joint disease, sinuses, kidneys, thyroid and bladder. In this paper, we developed an automated bone scan lesion segmentation method that implements intensity normalization, a two-threshold model, and automated detection and removal of areas consistent with non-malignant processes from the segmentation. The two-threshold model serves to account for outlier bone scans with elevated and diffuse intensity distributions. Parameters to remove degenerative joint disease were trained using a multi-start Nelder-Mead simplex optimization scheme. The segmentation reference standard was constructed manually by a panel of physicians. We compared the performance of the proposed method against a previously published method. The results of a two-fold cross validation show that the overlap ratio improved in 67.0% of scans, with an average improvement of 5.1% points.

  4. Fused Zirconia

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    ScopeThis standard specifies the terms,definitions,classification,brands,technical requirements,test methods,inspection rules,packing,marking,transportation,storage,and quality certificate of fused zirconia.This standard is applicable to monoclinic fused zirconia and partially stabilized fused zirconia.

  5. A joint shape evolution approach to medical image segmentation using expectation-maximization algorithm.

    Science.gov (United States)

    Farzinfar, Mahshid; Teoh, Eam Khwang; Xue, Zhong

    2011-11-01

    This study proposes an expectation-maximization (EM)-based curve evolution algorithm for segmentation of magnetic resonance brain images. In the proposed algorithm, the evolution curve is constrained not only by a shape-based statistical model but also by a hidden variable model from image observation. The hidden variable model herein is defined by the local voxel labeling, which is unknown and estimated by the expected likelihood function derived from the image data and prior anatomical knowledge. In the M-step, the shapes of the structures are estimated jointly by encoding the hidden variable model and the statistical prior model obtained from the training stage. In the E-step, the expected observation likelihood and the prior distribution of the hidden variables are estimated. In experiments, the proposed automatic segmentation algorithm is applied to multiple gray nuclei structures such as caudate, putamens and thalamus of three-dimensional magnetic resonance imaging in volunteers and patients. As for the robustness and accuracy of the segmentation algorithm, the results of the proposed EM-joint shape-based algorithm outperformed those obtained using the statistical shape model-based techniques in the same framework and a current state-of-the-art region competition level set method.

  6. Focused shape models for hip joint segmentation in 3D magnetic resonance images.

    Science.gov (United States)

    Chandra, Shekhar S; Xia, Ying; Engstrom, Craig; Crozier, Stuart; Schwarz, Raphael; Fripp, Jurgen

    2014-04-01

    Deformable models incorporating shape priors have proved to be a successful approach in segmenting anatomical regions and specific structures in medical images. This paper introduces weighted shape priors for deformable models in the context of 3D magnetic resonance (MR) image segmentation of the bony elements of the human hip joint. The fully automated approach allows the focusing of the shape model energy to a priori selected anatomical structures or regions of clinical interest by preferentially ordering the shape representation (or eigen-modes) within this type of model to the highly weighted areas. This focused shape model improves accuracy of the shape constraints in those regions compared to standard approaches. The proposed method achieved femoral head and acetabular bone segmentation mean absolute surface distance errors of 0.55±0.18mm and 0.75±0.20mm respectively in 35 3D unilateral MR datasets from 25 subjects acquired at 3T with different limited field of views for individual bony components of the hip joint.

  7. Multi-atlas segmentation with joint label fusion and corrective learning-an open source implementation.

    Science.gov (United States)

    Wang, Hongzhi; Yushkevich, Paul A

    2013-01-01

    Label fusion based multi-atlas segmentation has proven to be one of the most competitive techniques for medical image segmentation. This technique transfers segmentations from expert-labeled images, called atlases, to a novel image using deformable image registration. Errors produced by label transfer are further reduced by label fusion that combines the results produced by all atlases into a consensus solution. Among the proposed label fusion strategies, weighted voting with spatially varying weight distributions derived from atlas-target intensity similarity is a simple and highly effective label fusion technique. However, one limitation of most weighted voting methods is that the weights are computed independently for each atlas, without taking into account the fact that different atlases may produce similar label errors. To address this problem, we recently developed the joint label fusion technique and the corrective learning technique, which won the first place of the 2012 MICCAI Multi-Atlas Labeling Challenge and was one of the top performers in 2013 MICCAI Segmentation: Algorithms, Theory and Applications (SATA) challenge. To make our techniques more accessible to the scientific research community, we describe an Insight-Toolkit based open source implementation of our label fusion methods. Our implementation extends our methods to work with multi-modality imaging data and is more suitable for segmentation problems with multiple labels. We demonstrate the usage of our tools through applying them to the 2012 MICCAI Multi-Atlas Labeling Challenge brain image dataset and the 2013 SATA challenge canine leg image dataset. We report the best results on these two datasets so far.

  8. Multi-Atlas Segmentation with Joint Label Fusion and Corrective Learning - An Open Source Implementation

    Directory of Open Access Journals (Sweden)

    Hongzhi eWang

    2013-11-01

    Full Text Available Label fusion based multi-atlas segmentation has proven to be one of the most competitive techniques for medical image segmentation. This technique transfers segmentations from expert-labeled images, called atlases, to a novel image using deformable image registration. Errors produced by label transfer are further reduced by label fusion that combines the results produced by all atlases into a consensus solution. Among the proposed label fusion strategies, weighted voting with spatially varying weight distributions derived from atlas-target intensity similarity is a simple and highly effective label fusion technique. However, one limitation of most weighted voting methods is that the weights are computed independently for each atlas, without taking into account the fact that different atlases may produce similar label errors. To address this problem, we recently developed the joint label fusion technique and the corrective learning technique, which won the first place of the 2012 MICCAI Multi-Atlas Labeling Challenge and was one of the top performers in 2013 MICCAI Segmentation: Algorithms, Theory and Applications (SATA challenge. To make our techniques more accessible to the scientific research community, we describe an Insight-Toolkit based open source implementation of our label fusion methods. Our implementation extends our methods to work with multi-modality imaging data and is more suitable for segmentation problems with multiple labels. We demonstrate the usage of our tools through applying them to the 2012 MICCAI Multi-Atlas Labeling Challenge brain image dataset and the 2013 SATA challenge canine leg image dataset. We report the best results on these two datasets so far.

  9. Segment-specific association between cervical pillar hyperplasia (CPH and degenerative joint disease (DJD

    Directory of Open Access Journals (Sweden)

    Peterson Cynthia K

    2006-09-01

    Full Text Available Abstract Background Cervical pillar hyperplasia (CPH is a recently described phenomenon of unknown etiology and clinical significance. Global assessment of pillar hyperplasia of the cervical spine as a unit has not shown a relationship with degenerative joint disease, but a more sensible explanation of the architectural influence of CPH on cervical spine biomechanics may be segment-specific. Objective The objective of this study was to determine the level of association between degenerative joint disease (DJD and cervical pillar hyperplasia (CPH in an age- and gender-matched sample on a [cervical spine] by-level basis. Research Methods Two-hundred and forty radiographs were collected from subjects ranging in age between 40 and 69 years. The two primary outcome measures used in the study were the segmental presence/absence of cervical pillar hyperplasia from C3 to C6, and segment-specific presence/absence of degenerative joint disease from C1 to C7. Contingency Coefficients, at the 5% level of significance, at each level, were used to determine the strength of the association between CPH and DJD. Odds Ratios (OR with their 95% Confidence Intervals (95% CI were also calculated at each level to assess the strength of the association. Results Our study suggests that an approximately two-to-one odds, or a weak-to-moderate correlation, exists at C4 and C5 CPH and adjacent level degenerative disc disease (DDD; with the strongest (overall associations demonstrated between C4 CPH and C4–5 DDD and between C5 CPH and C5–6 DDD. Age-stratified results demonstrated a similar pattern of association, even reaching the initially hypothesized OR ≥ 5.0 (95% CI > 1.0 or "moderately-strong correlation of C ≥ .4 (p ≤ .05" in some age categories, including the 40–44, 50–59, and 60–64 years of age subgroups; these ORs were as follows: OR = 5.5 (95% CI 1.39–21.59; OR = 6.7 (95% CI 1.65–27.34; and OR = 5.3 (95% CI 1.35–21.14, respectively

  10. Spray Fused Coating and Properties of Welded Joints%火焰喷熔涂层与焊接接头性能研究

    Institute of Scientific and Technical Information of China (English)

    赵小辉; 王东坡; 邓彩艳; 王颖; 徐艳

    2012-01-01

    采用Ni60A合金粉末对Q235B钢十字焊接接头进行了喷熔修形处理.通过对涂层和焊缝的金相、扫描电镜、能谱等分析,研究了涂层与基体间的冶金结合情况,发现涂层组织致密、非金属夹杂物少、孔隙率低,与基体实现了良好的冶金结合.喷熔涂层本身的强度直接影响着十字焊接接头低周疲劳强度的大小.为此,通过有限元模拟和拉伸试验测定了涂层的抗开裂力值的大小.结果表明:当应力值为350MPa时涂层开裂,说明涂层自身强度较高.在应力比为0.1、平均应力为186MPa的情况下,喷熔接头的低周疲劳寿命均超过13 000周次以上,并且断裂位置均在母材.%Cruciform welded joints of Q235B steel was processed through modification of spray fusing with nickelbase alloy powder of Ni60A. The condition of metallurgical combination between coating and weld was examined by metallographical, SEM and energy spectrum analysis. Little non-metallic inclusion and lower porosity were found in the coating. The coating and weld achieved good metallurgical combination. The intensity of spray coating directly influences low-cycle fatigue strength of welded joints. Therefore, the cracking resistance force value was measured through simulation and tensile test. The result showed that the coating crazed when stress value was 350 Mpa, which indicated that strength of coating itself was higher. Low-cycle fatigue life of spray fused welded joint was over 13 000 cycles under the condition of stress ratio being 0. 1 and average stress being 186 Mpa, and fracture positions were at the base material.

  11. Fused silica capillaries with two segments of different internal diameters and inner surface roughnesses prepared by etching with supercritical water and used for volume coupling electrophoresis.

    Science.gov (United States)

    Horká, Marie; Karásek, Pavel; Roth, Michal; Šlais, Karel

    2017-02-22

    In this work, single-piece fused silica capillaries with two different internal diameter segments featuring different inner surface roughness were prepared by new etching technology with supercritical water and used for volume coupling electrophoresis. The concept of separation and online pre-concentration of analytes in high conductivity matrix is based on the online large-volume sample pre-concentration by the combination of transient isotachophoretic stacking and sweeping of charged proteins in micellar electrokinetic chromatography using non-ionogenic surfactant. The modified surface roughness step helped to the significant narrowing of the zones of examined analytes. The sweeping and separating steps were accomplished simultaneously by the use of phosphate buffer (pH 7) containing ethanol, non-ionogenic surfactant Brij 35, and polyethylene glycol (PEG 10000) after sample injection. Sample solution of a large volume (maximum 3.7 μL) dissolved in physiological saline solution was injected into the wider end of capillary with inlet inner diameter from 150, 185 or 218 μm. The calibration plots were linear (R(2) ∼ 0.9993) over a 0.060-1 μg/mL range for the proteins used, albumin and cytochrome c. The peak area RSDs from at least 20 independent measuremens were below 3.2%. This online pre-concentration technique produced a more than 196-fold increase in sensitivity, and it can be applied for detection of, e.g. the presence of albumin in urine (0.060 μg/mL).

  12. Rigid model-based 3D segmentation of the bones of joints in MR and CT images for motion analysis.

    Science.gov (United States)

    Liu, Jiamin; Udupa, Jayaram K; Saha, Punam K; Odhner, Dewey; Hirsch, Bruce E; Siegler, Sorin; Simon, Scott; Winkelstein, Beth A

    2008-08-01

    There are several medical application areas that require the segmentation and separation of the component bones of joints in a sequence of images of the joint acquired under various loading conditions, our own target area being joint motion analysis. This is a challenging problem due to the proximity of bones at the joint, partial volume effects, and other imaging modality-specific factors that confound boundary contrast. In this article, a two-step model-based segmentation strategy is proposed that utilizes the unique context of the current application wherein the shape of each individual bone is preserved in all scans of a particular joint while the spatial arrangement of the bones alters significantly among bones and scans. In the first step, a rigid deterministic model of the bone is generated from a segmentation of the bone in the image corresponding to one position of the joint by using the live wire method. Subsequently, in other images of the same joint, this model is used to search for the same bone by minimizing an energy function that utilizes both boundary- and region-based information. An evaluation of the method by utilizing a total of 60 data sets on MR and CT images of the ankle complex and cervical spine indicates that the segmentations agree very closely with the live wire segmentations, yielding true positive and false positive volume fractions in the range 89%-97% and 0.2%-0.7%. The method requires 1-2 minutes of operator time and 6-7 min of computer time per data set, which makes it significantly more efficient than live wire-the method currently available for the task that can be used routinely.

  13. Modeling 4D Human-Object Interactions for Joint Event Segmentation, Recognition, and Object Localization.

    Science.gov (United States)

    Wei, Ping; Zhao, Yibiao; Zheng, Nanning; Zhu, Song-Chun

    2016-06-01

    In this paper, we present a 4D human-object interaction (4DHOI) model for solving three vision tasks jointly: i) event segmentation from a video sequence, ii) event recognition and parsing, and iii) contextual object localization. The 4DHOI model represents the geometric, temporal, and semantic relations in daily events involving human-object interactions. In 3D space, the interactions of human poses and contextual objects are modeled by semantic co-occurrence and geometric compatibility. On the time axis, the interactions are represented as a sequence of atomic event transitions with coherent objects. The 4DHOI model is a hierarchical spatial-temporal graph representation which can be used for inferring scene functionality and object affordance. The graph structures and parameters are learned using an ordered expectation maximization algorithm which mines the spatial-temporal structures of events from RGB-D video samples. Given an input RGB-D video, the inference is performed by a dynamic programming beam search algorithm which simultaneously carries out event segmentation, recognition, and object localization. We collected and released a large multiview RGB-D event dataset which contains 3,815 video sequences and 383,036 RGB-D frames captured by three RGB-D cameras. The experimental results on three challenging datasets demonstrate the strength of the proposed method.

  14. Iterative framework for the joint segmentation and CT synthesis of MR images : application to MRI-only radiotherapy treatment planning

    NARCIS (Netherlands)

    Burgos, Ninon; Guerreiro, Filipa; McClelland, Jamie; Presles, Benoit; Modat, Marc; Nill, Simeon; Dearnaley, David; deSouza, Nandita; Oelfke, Uwe; Knopf, Antje-Christin; Ourselin, Sebastien; Cardoso, M. Jorge

    2017-01-01

    To tackle the problem of magnetic resonance imaging (MRI)-only radiotherapy treatment planning (RTP), we propose a multi-atlas information propagation scheme that jointly segments organs and generates pseudo x-ray computed tomography (CT) data from structural MR images (T1-weighted and T2-weighted).

  15. The effect of perturbing body segment parameters on calculated joint moments and muscle forces during gait.

    Science.gov (United States)

    Wesseling, Mariska; de Groote, Friedl; Jonkers, Ilse

    2014-01-22

    This study examined the effect of body segment parameter (BSP) perturbations on joint moments calculated using an inverse dynamics procedure and muscle forces calculated using computed muscle control (CMC) during gait. BSP (i.e. segment mass, center of mass location (com) and inertia tensor) of the left thigh, shank and foot of a scaled musculoskeletal model were perturbed. These perturbations started from their nominal value and were adjusted to ±40% in steps of 10%, for both individual as well as combined perturbations in BSP. For all perturbations, an inverse dynamics procedure calculated the ankle, knee and hip moments based on an identical inverse kinematics solution. Furthermore, the effect of applying a residual reduction algorithm (RRA) was investigated. Muscle excitations and resulting muscle forces were calculated using CMC. The results show only a limited effect of an individual parameter perturbation on the calculated moments, where the largest effect is found when perturbing the shank com (MS(com,shank), the ratio of absolute difference in torque and relative parameter perturbation, is maximally -7.81 N m for hip flexion moment). The additional influence of perturbing two parameters simultaneously is small (MS(mass+com,thigh) is maximally 15.2 N m for hip flexion moment). RRA made small changes to the model to increase the dynamic consistency of the simulation (after RRA MS(com,shank) is maximally 5.01 N m). CMC results show large differences in muscle forces when BSP are perturbed. These result from the underlying forward integration of the dynamic equations.

  16. Joint segmentation of 3D femoral lumen and outer wall surfaces from MR images.

    Science.gov (United States)

    Ukwatta, Eranga; Yuan, Jing; Qiu, Wu; Rajchl, Martin; Chiu, Bernard; Shavakh, Shadi; Xu, Jianrong; Fenster, Aaron

    2013-01-01

    We propose a novel algorithm to jointly delineate the femoral artery lumen and outer wall surfaces from 3D black-blood MR images, while enforcing the spatial consistency of the reoriented MR slices along the medial axis of the femoral artery. We demonstrate that the resulting optimization problem of the proposed segmentation can be solved globally and exactly by means of convex relaxation, for which we introduce a novel coupled continuous max-flow (CCOMF) model based on an Ishikawa-type flow configuration and show its duality to the studied convex relaxed optimization problem. Using the proposed CCMF model, the exactness and globalness of its dual convex relaxation problem is proven. Experiment results demonstrate that the proposed method yielded high accuracy (i.e. Dice similarity coefficient > 85%) for both the lumen and outer wall and high reproducibility (intra-class correlation coefficient of 0.95) for generating vessel wall area. The proposed method outperformed the previous method, in terms of computation time, by a factor of pproximately 20.

  17. Loading effects of anterior cervical spine fusion on adjacent segments

    Directory of Open Access Journals (Sweden)

    Chien-Shiung Wang

    2012-11-01

    Full Text Available Adjacent segment degeneration typically follows anterior cervical spine fusion. However, the primary cause of adjacent segment degeneration remains unknown. Therefore, in order to identify the loading effects that cause adjacent segment degeneration, this study examined the loading effects to superior segments adjacent to fused bone following anterior cervical spine fusion. The C3–C6 cervical spine segments of 12 sheep were examined. Specimens were divided into the following groups: intact spine (group 1; and C5–C6 segments that were fused via cage-instrumented plate fixation (group 2. Specimens were cycled between 20° flexion and 15° extension with a displacement control of 1°/second. The tested parameters included the range of motion (ROM of each segment, torque and strain on both the body and inferior articular process at the superior segments (C3–C4 adjacent to the fused bone, and the position of the neutral axis of stress at under 20° flexion and 15° extension. Under flexion and Group 2, torque, ROM, and strain on both the bodies and facets of superior segments adjacent to the fused bone were higher than those of Group 1. Under extension and Group 2, ROM for the fused segment was less than that of Group 1; torque, ROM, and stress on both the bodies and facets of superior segments adjacent to the fused bone were higher than those of Group 1. These analytical results indicate that the muscles and ligaments require greater force to achieve cervical motion than the intact spine following anterior cervical spine fusion. In addition, ROM and stress on the bodies and facets of the joint segments adjacent to the fused bone were significantly increased. Under flexion, the neutral axis of the stress on the adjacent segment moved backward, and the stress on the bodies of the segments adjacent to the fused bone increased. These comparative results indicate that increased stress on the adjacent segments is caused by stress-shielding effects

  18. Joint Target Tracking, Recognition and Segmentation for Infrared Imagery Using a Shape Manifold-Based Level Set

    Directory of Open Access Journals (Sweden)

    Jiulu Gong

    2014-06-01

    Full Text Available We propose a new integrated target tracking, recognition and segmentation algorithm, called ATR-Seg, for infrared imagery. ATR-Seg is formulated in a probabilistic shape-aware level set framework that incorporates a joint view-identity manifold (JVIM for target shape modeling. As a shape generative model, JVIM features a unified manifold structure in the latent space that is embedded with one view-independent identity manifold and infinite identity-dependent view manifolds. In the ATR-Seg algorithm, the ATR problem formulated as a sequential level-set optimization process over the latent space of JVIM, so that tracking and recognition can be jointly optimized via implicit shape matching where target segmentation is achieved as a by-product without any pre-processing or feature extraction. Experimental results on the recently released SENSIAC ATR database demonstrate the advantages and effectiveness of ATR-Seg over two recent ATR algorithms that involve explicit shape matching.

  19. Oppugning the assumptions of spatial averaging of segment and joint orientations.

    Science.gov (United States)

    Pierrynowski, Michael Raymond; Ball, Kevin Arthur

    2009-02-09

    Movement scientists frequently calculate "arithmetic averages" when examining body segment or joint orientations. Such calculations appear routinely, yet are fundamentally flawed. Three-dimensional orientation data are computed as matrices, yet three-ordered Euler/Cardan/Bryant angle parameters are frequently used for interpretation. These parameters are not geometrically independent; thus, the conventional process of averaging each parameter is incorrect. The process of arithmetic averaging also assumes that the distances between data are linear (Euclidean); however, for the orientation data these distances are geodesically curved (Riemannian). Therefore we question (oppugn) whether use of the conventional averaging approach is an appropriate statistic. Fortunately, exact methods of averaging orientation data have been developed which both circumvent the parameterization issue, and explicitly acknowledge the Euclidean or Riemannian distance measures. The details of these matrix-based averaging methods are presented and their theoretical advantages discussed. The Euclidian and Riemannian approaches offer appealing advantages over the conventional technique. With respect to practical biomechanical relevancy, examinations of simulated data suggest that for sets of orientation data possessing characteristics of low dispersion, an isotropic distribution, and less than 30 degrees second and third angle parameters, discrepancies with the conventional approach are less than 1.1 degrees . However, beyond these limits, arithmetic averaging can have substantive non-linear inaccuracies in all three parameterized angles. The biomechanics community is encouraged to recognize that limitations exist with the use of the conventional method of averaging orientations. Investigations requiring more robust spatial averaging over a broader range of orientations may benefit from the use of matrix-based Euclidean or Riemannian calculations.

  20. A generative probability model of joint label fusion for multi-atlas based brain segmentation.

    Science.gov (United States)

    Wu, Guorong; Wang, Qian; Zhang, Daoqiang; Nie, Feiping; Huang, Heng; Shen, Dinggang

    2014-08-01

    Automated labeling of anatomical structures in medical images is very important in many neuroscience studies. Recently, patch-based labeling has been widely investigated to alleviate the possible mis-alignment when registering atlases to the target image. However, the weights used for label fusion from the registered atlases are generally computed independently and thus lack the capability of preventing the ambiguous atlas patches from contributing to the label fusion. More critically, these weights are often calculated based only on the simple patch similarity, thus not necessarily providing optimal solution for label fusion. To address these limitations, we propose a generative probability model to describe the procedure of label fusion in a multi-atlas scenario, for the goal of labeling each point in the target image by the best representative atlas patches that also have the largest labeling unanimity in labeling the underlying point correctly. Specifically, sparsity constraint is imposed upon label fusion weights, in order to select a small number of atlas patches that best represent the underlying target patch, thus reducing the risks of including the misleading atlas patches. The labeling unanimity among atlas patches is achieved by exploring their dependencies, where we model these dependencies as the joint probability of each pair of atlas patches in correctly predicting the labels, by analyzing the correlation of their morphological error patterns and also the labeling consensus among atlases. The patch dependencies will be further recursively updated based on the latest labeling results to correct the possible labeling errors, which falls to the Expectation Maximization (EM) framework. To demonstrate the labeling performance, we have comprehensively evaluated our patch-based labeling method on the whole brain parcellation and hippocampus segmentation. Promising labeling results have been achieved with comparison to the conventional patch-based labeling

  1. Multi-rigid image segmentation and registration for the analysis of joint motion from three-dimensional magnetic resonance imaging.

    Science.gov (United States)

    Hu, Yangqiu; Ledoux, William R; Fassbind, Michael; Rohr, Eric S; Sangeorzan, Bruce J; Haynor, David

    2011-10-01

    We report an image segmentation and registration method for studying joint morphology and kinematics from in vivo magnetic resonance imaging (MRI) scans and its application to the analysis of foot and ankle joint motion. Using an MRI-compatible positioning device, a foot was scanned in a single neutral and seven other positions ranging from maximum plantar flexion, inversion, and internal rotation to maximum dorsiflexion, eversion, and external rotation. A segmentation method combining graph cuts and level set was developed. In the subsequent registration step, a separate rigid body transformation for each bone was obtained by registering the neutral position dataset to each of the other ones, which produced an accurate description of the motion between them. The segmentation algorithm allowed a user to interactively delineate 14 foot bones in the neutral position volume in less than 30 min total (user and computer processing unit [CPU]) time. Registration to the seven other positions took approximately 10 additional minutes of user time and 5.25 h of CPU time. For validation, our results were compared with those obtained from 3DViewnix, a semiautomatic segmentation program. We achieved excellent agreement, with volume overlap ratios greater than 88% for all bones excluding the intermediate cuneiform and the lesser metatarsals. For the registration of the neutral scan to the seven other positions, the average overlap ratio is 94.25%, while the minimum overlap ratio is 89.49% for the tibia between the neutral position and position 1, which might be due to different fields of view (FOV). To process a single foot in eight positions, our tool requires only minimal user interaction time (less than 30 min total), a level of improvement that has the potential to make joint motion analysis from MRI practical in research and clinical applications.

  2. Segmentation of knee joints in x-ray images using decomposition-based sweeping and graph search

    Science.gov (United States)

    Mu, Jian; Liu, Xiaomin; Luan, Shuang; Heintz, Philip H.; Mlady, Gary W.; Chen, Danny Z.

    2011-03-01

    Plain radiography (i.e., X-ray imaging) provides an effective and economical imaging modality for diagnosing knee illnesses and injuries. Automatically segmenting and analyzing knee radiographs is a challenging problem. In this paper, we present a new approach for accurately segmenting the knee joint in X-ray images. We first use the Gaussian high-pass filter to remove homogeneous regions which are unlikely to appear on bone contours. We then presegment the bones and develop a novel decomposition-based sweeping algorithm for extracting bone contour topology from the filtered skeletonized images. Our sweeping algorithm decomposes the bone structures into several relatively simple components and deals with each component separately based on its geometric characteristics using a sweeping strategy. Utilizing the presegmentation, we construct a graph to model the bone topology and apply an optimal graph search algorithm to optimize the segmentation results (with respect to our cost function defined on the bone boundaries). Our segmented results match well with the manual tracing results by radiologists. Our segmentation approach can be a valuable tool for assisting radiologists and X-ray technologists in clinical practice and training.

  3. Hybrid PET/MRI co-segmentation based on joint fuzzy connectedness and graph cut.

    Science.gov (United States)

    Sbei, Arafet; ElBedoui, Khaoula; Barhoumi, Walid; Maksud, Philippe; Maktouf, Chokri

    2017-10-01

    Tumor segmentation from hybrid PET/MRI scans may be highly beneficial in radiotherapy treatment planning. Indeed, it gives for both modalities the suitable information that could make the delineation of tumors more accurate than using each one apart. We aim in this work to propose a co-segmentation method that deals with several challenges, notably the lack of one-to-one correspondence between tumors of the two modalities and the boundaries' smoothing. The proposed method is designed to surpass these limits, we propose a segmentation method based on the GCsum(max) technique. The method takes the advantage of Iterative Relative Fuzzy Connectedness (IRFC) on seeds initialization, and the standard min-cut/max-flow technique for the boundary smoothing. Seed initialization was accurately performed thanks to high uptake regions on PET. Besides, a visibility weighting scheme was adapted to achieve the task of co-segmentation using the IRFC algorithm. Then, given the co-segmented regions, we introduce a morphological-based technique that provides object seeds to standard Graph Cut (GC) allowing it to avoid the shrinking problem. Finally, for each modality, the segmentation task is formulated as an energy minimization problem which is resolved by a min-cut/max-flow technique. The overlap ratio (denoted DSC) between our segmentation results and the ground-truth for PET images is 92.63  ±  1.03, while the DSC for MRI images is 90.61  ±  3.70. The proposed method was tested on different types of diseases and it outperformed the state-of-the-art methods. We show its superiority in terms of assymetric relation between PET and MRI and tumors heterogeneity. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Segmentation and measurement of collagen fibers for shoulder and joint therapy studies

    Energy Technology Data Exchange (ETDEWEB)

    Mascio, L. [Lawrence Livermore National Lab., CA (United States)

    1994-11-15

    Various shoulder instabilities are debilitating, especially in individuals who perform overhead activities. Thermal modification of soft tissues in joints may allow precise alteration of these tissues` mechanical and/or structural properties to enhance joint function without inducing cell death or an inflammatory response. Several studies have evaluated laser energy for tissue welding. The collective findings are promising, and the next step is to identify the mechanisms responsible for laser-induced capsular tissue alternation, and the short- and long-term effects of non-ablative laser energy on joint capsular tissue. One step toward this goal is to compare the effect of three laser energy densities on the histologic properties of the tissue evaluating the architecture of the collagen (including density, fibril diameter distribution, and interfibrillar space) in sheep at various time intervals after surgery. The specific computer algorithms that are being used to make these measurements will be described.

  5. Finite element analysis of residual stress of welded joints modified by spray fusing%喷熔修形后的焊接接头残余应力有限元分析

    Institute of Scientific and Technical Information of China (English)

    赵小辉; 王东坡; 邓彩艳

    2011-01-01

    In this paper,Ni60 alloy powders were used to improve the fatigue strength of cruciform joints of Q235B through modification of spray fusing.Test results showed that the section shape of welded joints can be improved by flame spraying.High cycle fatigue test results showed that 2×106 cycles offset fatigue strength of the welded joints spray fused by Ni60 increased by 64.5%.The thermal stress was simulated by the finite element(ANSYS12.0) based on spraying parameters.Simulation results show that,the residual stress of substrate material and coating layer is still tensile stress and compared with as-welded joints,the magnitude of tensile stress decreases slightly.The residual stress of as-welded and coating surface is about 238 MPa and 182 MPa respectively.Thus,the residual stress is decreased by 24% after spray fusing.%采用Ni60合金粉末对Q235B钢焊态十字接头进行了氧—乙炔火焰喷熔处理,同时进行了高频疲劳试验.分析认为喷熔修形改善了焊接接头的几何外形.喷熔修形态十字接头在2×106循环周次下的疲劳强度比原始焊态提高了64.5%.基于氧—乙炔火焰喷熔工艺参数,采用ANSYS12.0软件对喷熔过程进行了热-应力耦合的有限元模拟,分析认为,焊缝和涂层表面的残余应力仍为拉应力,但是残余拉应力的大小和喷熔前原始焊态接头表层的残余拉应力相比略微减小.原始焊态接头表层的拉应力约为238 MPa,喷熔修形后喷熔层表面的残余拉应力约

  6. A comparison of subtalar joint motion during anticipated medial cutting turns and level walking using a multi-segment foot model.

    Science.gov (United States)

    Jenkyn, T R; Shultz, R; Giffin, J R; Birmingham, T B

    2010-02-01

    The weight-bearing in-vivo kinematics and kinetics of the talocrural joint, subtalar joint and joints of the foot were quantified using optical motion analysis. Twelve healthy subjects were studied during level walking and anticipated medial turns at self-selected pace. A multi-segment model of the foot using skin-mounted marker triads tracked four foot segments: the hindfoot, midfoot, lateral and medial forefoot. The lower leg and thigh were also tracked. Motion between each of the segments could occur in three degrees of rotational freedom, but only six inter-segmental motions were reported in this study: (1) talocrural dorsi-plantar-flexion, (2) subtalar inversion-eversion, (3) frontal plane hindfoot motion, (4) transverse plane hindfoot motion, (5) forefoot supination-pronation twisting and (6) the height-to-length ratio of the medial longitudinal arch. The motion at the subtalar joint during stance phase of walking (eversion then inversion) was reversed during a turning task (inversion then eversion). The external subtalar joint moment was also changed from a moderate eversion moment during walking to a larger inversion moment during the turn. The kinematics of the talocrural joint and the joints of the foot were similar between these two tasks. During a medial turn, the subtalar joint may act to maintain the motions in the foot and talocrural joint that occur during level walking. This is occurring despite the conspicuously different trajectory of the centre of mass of the body. This may allow the foot complex to maintain its function of energy absorption followed by energy return during stance phase that is best suited to level walking.

  7. Iterative framework for the joint segmentation and CT synthesis of MR images: application to MRI-only radiotherapy treatment planning

    Science.gov (United States)

    Burgos, Ninon; Guerreiro, Filipa; McClelland, Jamie; Presles, Benoît; Modat, Marc; Nill, Simeon; Dearnaley, David; deSouza, Nandita; Oelfke, Uwe; Knopf, Antje-Christin; Ourselin, Sébastien; Cardoso, M. Jorge

    2017-06-01

    To tackle the problem of magnetic resonance imaging (MRI)-only radiotherapy treatment planning (RTP), we propose a multi-atlas information propagation scheme that jointly segments organs and generates pseudo x-ray computed tomography (CT) data from structural MR images (T1-weighted and T2-weighted). As the performance of the method strongly depends on the quality of the atlas database composed of multiple sets of aligned MR, CT and segmented images, we also propose a robust way of registering atlas MR and CT images, which combines structure-guided registration, and CT and MR image synthesis. We first evaluated the proposed framework in terms of segmentation and CT synthesis accuracy on 15 subjects with prostate cancer. The segmentations obtained with the proposed method were compared using the Dice score coefficient (DSC) to the manual segmentations. Mean DSCs of 0.73, 0.90, 0.77 and 0.90 were obtained for the prostate, bladder, rectum and femur heads, respectively. The mean absolute error (MAE) and the mean error (ME) were computed between the reference CTs (non-rigidly aligned to the MRs) and the pseudo CTs generated with the proposed method. The MAE was on average 45.7+/- 4.6 HU and the ME -1.6+/- 7.7 HU. We then performed a dosimetric evaluation by re-calculating plans on the pseudo CTs and comparing them to the plans optimised on the reference CTs. We compared the cumulative dose volume histograms (DVH) obtained for the pseudo CTs to the DVH obtained for the reference CTs in the planning target volume (PTV) located in the prostate, and in the organs at risk at different DVH points. We obtained average differences of -0.14 % in the PTV for {{D}98 % } , and between -0.14 % and 0.05% in the PTV, bladder, rectum and femur heads for D mean and {{D}2 % } . Overall, we demonstrate that the proposed framework is able to automatically generate accurate pseudo CT images and segmentations in the pelvic region, potentially bypassing the need for CT scan for accurate RTP.

  8. FluoRender: joint freehand segmentation and visualization for many-channel fluorescence data analysis.

    Science.gov (United States)

    Wan, Yong; Otsuna, Hideo; Holman, Holly A; Bagley, Brig; Ito, Masayoshi; Lewis, A Kelsey; Colasanto, Mary; Kardon, Gabrielle; Ito, Kei; Hansen, Charles

    2017-05-26

    Image segmentation and registration techniques have enabled biologists to place large amounts of volume data from fluorescence microscopy, morphed three-dimensionally, onto a common spatial frame. Existing tools built on volume visualization pipelines for single channel or red-green-blue (RGB) channels have become inadequate for the new challenges of fluorescence microscopy. For a three-dimensional atlas of the insect nervous system, hundreds of volume channels are rendered simultaneously, whereas fluorescence intensity values from each channel need to be preserved for versatile adjustment and analysis. Although several existing tools have incorporated support of multichannel data using various strategies, the lack of a flexible design has made true many-channel visualization and analysis unavailable. The most common practice for many-channel volume data presentation is still converting and rendering pseudosurfaces, which are inaccurate for both qualitative and quantitative evaluations. Here, we present an alternative design strategy that accommodates the visualization and analysis of about 100 volume channels, each of which can be interactively adjusted, selected, and segmented using freehand tools. Our multichannel visualization includes a multilevel streaming pipeline plus a triple-buffer compositing technique. Our method also preserves original fluorescence intensity values on graphics hardware, a crucial feature that allows graphics-processing-unit (GPU)-based processing for interactive data analysis, such as freehand segmentation. We have implemented the design strategies as a thorough restructuring of our original tool, FluoRender. The redesign of FluoRender not only maintains the existing multichannel capabilities for a greatly extended number of volume channels, but also enables new analysis functions for many-channel data from emerging biomedical-imaging techniques.

  9. A 4D biomechanical lung phantom for joint segmentation/registration evaluation

    Science.gov (United States)

    Markel, Daniel; Levesque, Ives; Larkin, Joe; Léger, Pierre; El Naqa, Issam

    2016-10-01

    At present, there exists few openly available methods for evaluation of simultaneous segmentation and registration algorithms. These methods allow for a combination of both techniques to track the tumor in complex settings such as adaptive radiotherapy. We have produced a quality assurance platform for evaluating this specific subset of algorithms using a preserved porcine lung in such that it is multi-modality compatible: positron emission tomography (PET), computer tomography (CT) and magnetic resonance imaging (MRI). A computer controlled respirator was constructed to pneumatically manipulate the lungs in order to replicate human breathing traces. A registration ground truth was provided using an in-house bifurcation tracking pipeline. Segmentation ground truth was provided by synthetic multi-compartment lesions to simulate biologically active tumor, background tissue and a necrotic core. The bifurcation tracking pipeline results were compared to digital deformations and used to evaluate three registration algorithms, Diffeomorphic demons, fast-symmetric forces demons and MiMVista’s deformable registration tool. Three segmentation algorithms the Chan Vese level sets method, a Hybrid technique and the multi-valued level sets algorithm. The respirator was able to replicate three seperate breathing traces with a mean accuracy of 2-2.2%. Bifurcation tracking error was found to be sub-voxel when using human CT data for displacements up to 6.5 cm and approximately 1.5 voxel widths for displacements up to 3.5 cm for the porcine lungs. For the fast-symmetric, diffeomorphic and MiMvista registration algorithms, mean geometric errors were found to be 0.430+/- 0.001 , 0.416+/- 0.001 and 0.605+/- 0.002 voxels widths respectively using the vector field differences and 0.4+/- 0.2 , 0.4+/- 0.2 and 0.6+/- 0.2 voxel widths using the bifurcation tracking pipeline. The proposed phantom was found sufficient for accurate evaluation of registration and segmentation algorithms

  10. Differences in segmental coordination and postural control in a multi-joint dance movement: développé arabesque.

    Science.gov (United States)

    Bronner, Shaw

    2012-03-01

    Analysis of skill at multiple points on the learning continuum provides insight into how complex limb and postural organization is modified with extended practice. Dancers at three skill levels were compared performing a domain-specific movement (développé arabesque) to identify motor control parameters underlying skill acquisition of a sequential multi-joint trunk and extremity movement. It was hypothesized that general organization would be similar between groups, but that segmental coordination and postural control would differ with skill level. Twenty-seven expert, advanced, and intermediate dancers performed six repetitions of an arabesque sequence with the right limb. Data were acquired with a five-camera motion analysis system. Differences between groups in pelvis and gesture limb displacement, joint coordination patterns, and variability were determined using ANOVA with post hoc comparisons where applicable. Subjects displayed similar movement organization and timing. Differences were found in postural pelvic control and intra- and inter-limb coordination. These differences were most apparent during the arabesque phase. Control of the pelvis appears to be a key area that requires prolonged practice to master.

  11. Shear strength of match cast dry joints of precast concrete segmental bridges: proposal for Eurocode 2

    Directory of Open Access Journals (Sweden)

    Aparicio, J. A.

    2006-06-01

    Full Text Available This paper discusses a study on the performance of concretesegmental bridges with shear keys, focusing on theshear behaviour of castellated dry joints under ultimatelimit state conditions. The widely varying formulationused to evaluate joint shear strength were compiled,along with the experimental results published in the literatureon the subject. The various approaches were evaluatedby comparing their predictions of ultimate jointstrength to published empirical findings. The formulagiving the best prediction was adapted to the safety factorprovisions set out in Eurocode 2.Este trabajo presenta un estudio sobre el comportamientode puentes de dovelas de hormigon con llaves de cortante,centrado en el comportamiento a cortante de lasjuntas secas conjugadas en Estado Limite Ultimo. Se harealizado una exhaustiva recopilacion de la dispar formulacionexistente para evaluar la resistencia a cortante delas juntas. Se ha realizado, asimismo, una investigacionbibliografica de los resultados experimentales disponiblessobre este particular en la literatura. Los resultados recogidosen la bibliografia han sido comparados con la variadaformulacion existente para predecir la resistencia ultimade las juntas. La formula que mejor predice laresistencia ha sido identificada. Esta ha sido adaptada alformato de seguridad presente en el Eurocodigo 2.

  12. Evaluation of Anatomical and Functional Hip Joint Center Methods: The Effects of Activity Type, Gender, and Proximal Reference Segment.

    Science.gov (United States)

    McGibbon, C A; Fowler, J; Chase, S; Steeves, K; Landry, J; Mohamed, A

    2016-01-01

    Accurate hip joint center (HJC) location is critical when studying hip joint biomechanics. The HJC is often determined from anatomical methods, but functional methods are becoming increasingly popular. Several studies have examined these methods using simulations and in vivo gait data, but none has studied high-range of motion activities, such a chair rise, nor has HJC prediction been compared between males and females. Furthermore, anterior superior iliac spine (ASIS) marker visibility during chair rise can be problematic, requiring a sacral cluster as an alternative proximal segment; but functional HJC has not been explored using this approach. For this study, the quality of HJC measurement was based on the joint gap error (JGE), which is the difference in global HJC between proximal and distal reference segments. The aims of the present study were to: (1) determine if JGE varies between pelvic and sacral referenced HJC for functional and anatomical methods, (2) investigate which functional calibration motion results in the lowest JGE and if the JGE varies depending on movement type (gait versus chair rise) and gender, and (3) assess whether the functional HJC calibration results in lower JGE than commonly used anatomical approaches and if it varies with movement type and gender. Data were collected on 39 healthy adults (19 males and 20 females) aged 14-50 yr old. Participants performed four hip "calibration" tests (arc, cross, star, and star-arc), as well as gait and chair rise (activities of daily living (ADL)). Two common anatomical methods were used to estimate HJC and were compared to HJC computed using a published functional method with the calibration motions above, when using pelvis or sacral cluster as the proximal reference. For ADL trials, functional methods resulted in lower JGE (12-19 mm) compared to anatomical methods (13-34 mm). It was also found that women had significantly higher JGE compared to men and JGE was significantly higher for

  13. Patterns of primary afferent depolarization of segmental and ascending intraspinal collaterals of single joint afferents in the cat.

    Science.gov (United States)

    Rudomin, P; Lomelí, J

    2007-01-01

    We have examined in the anesthetized cat the threshold changes produced by sensory and supraspinal stimuli on intraspinal collaterals of single afferents from the posterior articular nerve (PAN). Forty-eight fibers were tested in the L3 segment, in or close to Clarke's column, and 70 fibers in the L6-L7 segments within the intermediate zone. Of these, 15 pairs of L3 and L6-L7 collaterals were from the same afferent. Antidromically activated fibers had conduction velocities between 23 and 74 m/s and peripheral thresholds between 1.1 and 4.7 times the threshold of the most excitable fibers (xT), most of them below 3 xT. PAN afferents were strongly depolarized by stimulation of muscle afferents and by cutaneous afferents, as well as by stimulation of the bulbar reticular formation and the midline raphe nuclei. Stimulation of muscle nerves (posterior biceps and semitendinosus, quadriceps) produced a larger PAD (primary afferent depolarization) in the L6-L7 than in the L3 terminations. Group II were more effective than group I muscle afferents. As with group I muscle afferents, the PAD elicited in PAN afferents by stimulation of muscle nerves could be inhibited by conditioning stimulation of cutaneous afferents. Stimulation of the cutaneous sural and superficial peroneal nerves increased the threshold of few terminations (i.e., produced primary afferent hyperpolarization, PAH) and reduced the threshold of many others, particularly of those tested in the L6-L7 segments. Yet, there was a substantial number of terminals where these conditioning stimuli had minor or no effects. Autogenetic stimulation of the PAN with trains of pulses increased the intraspinal threshold in 46% and reduced the threshold in 26% of fibers tested in the L6-L7 segments (no tests were made with trains of pulses on fibers ending in L3). These observations indicate that PAN afferents have a rather small autogenetic PAD, particularly if this is compared with the effects of heterogenetic stimulation

  14. The influence of estimated body segment parameters on predicted joint kinetics during diplegic cerebral palsy gait.

    Science.gov (United States)

    Kiernan, D; Walsh, M; O'Sullivan, R; O'Brien, T; Simms, C K

    2014-01-01

    Inverse Dynamic calculations are routinely used in joint moment and power estimates during gait with anthropometric data often taken from published sources. Many biomechanical analyses have highlighted the need to obtain subject-specific anthropometric data (e.g. Mass, Centre of Mass, Moments of Inertia) yet the types of imaging techniques required to achieve this are not always available in the clinical setting. Differences in anthropometric sets have been shown to affect the reactive force and moment calculations in normal subjects but the effect on a paediatric diplegic cerebral palsy group has not been investigated. The aim of this study was to investigate the effect of using different anthropometric sets on predicted sagittal plane moments during normal and diplegic cerebral palsy gait. Three published anthropometric sets were applied to the reactive force and moment calculations of 14 Cerebral Palsy and 14 Control subjects. Statistically significant differences were found when comparing the different anthropometric sets but variability in the resulting sagittal plane moment calculations between sets was low (0.01-0.07 Nm/kg). In addition, the GDI-Kinetic, used as an outcome variable to assess whether differences were clinically meaningful, indicated no clinically meaningful difference between sets. The results suggest that the effects of using different anthropometric sets on the kinetic profiles of normal and diplegic cerebral palsy subjects are clinically insignificant.

  15. Buckling of a Longitudinally Jointed Curved Composite Panel Arc Segment for Next Generation of Composite Heavy Lift Launch Vehicles: Verification Testing Analysis

    Science.gov (United States)

    Farrokh, Babak; Segal, Kenneth N.; Akkerman, Michael; Glenn, Ronald L.; Rodini, Benjamin T.; Fan, Wei-Ming; Kellas, Sortiris; Pineda, Evan J.

    2014-01-01

    In this work, an all-bonded out-of-autoclave (OoA) curved longitudinal composite joint concept, intended for use in the next generation of composite heavy lift launch vehicles, was evaluated and verified through finite element (FE) analysis, fabrication, testing, and post-test inspection. The joint was used to connect two curved, segmented, honeycomb sandwich panels representative of a Space Launch System (SLS) fairing design. The overall size of the resultant panel was 1.37 m by 0.74 m (54 in by 29 in), of which the joint comprised a 10.2 cm (4 in) wide longitudinal strip at the center. NASTRAN and ABAQUS were used to perform linear and non-linear analyses of the buckling and strength performance of the jointed panel. Geometric non-uniformities (i.e., surface contour imperfections) were measured and incorporated into the FE model and analysis. In addition, a sensitivity study of the specimens end condition showed that bonding face-sheet doublers to the panel's end, coupled with some stress relief features at corner-edges, can significantly reduce the stress concentrations near the load application points. Ultimately, the jointed panel was subjected to a compressive load. Load application was interrupted at the onset of buckling (at 356 kN 80 kips). A post-test non-destructive evaluation (NDE) showed that, as designed, buckling occurred without introducing any damage into the panel or the joint. The jointed panel was further capable of tolerating an impact damage to the same buckling load with no evidence of damage propagation. The OoA cured all-composite joint shows promise as a low mass factory joint for segmented barrels.

  16. Fast simultaneous determination of prominent polyphenols in vegetables and fruits by reversed phase liquid chromatography using a fused-core column

    OpenAIRE

    Marti, R.; Valcarcel, M.; Herrero-Martinez, J.M.; Cebolla Cornejo, Jaime; ROSELLO RIPOLLES, SALVADOR

    2015-01-01

    A reversed-phase high-performance liquid chromatography method with photodiode array detection has been developed enabling the joint determination of 17 prominent flavonoids and phenolic acids in vegetables and fruits. A multi-segmented gradient program using a fused-core column for the separation of several phenolic classes (phenolic acids and flavonoids) has been optimised. The influence of extraction conditions (sample freeze-drying, ultrasound extraction, solvent composition and extractio...

  17. Problematic Issues of Segmentation in the Formation of Consolidated Financial Statements by the Participants of Joint Ventures

    Directory of Open Access Journals (Sweden)

    Alla V. Dmitrenko

    2014-03-01

    Full Text Available The paper studies the topical issue of segmentation of consolidated financial statements. The author proposes to make a report on the assets, liabilities, income, expenses and financial results that are directly related to report segment or allocated to the report segment.

  18. Polymer optical fiber fuse

    CERN Document Server

    Mizuno, Yosuke; Tanaka, Hiroki; Nakamura, Kentaro

    2013-01-01

    Although high-transmission-capacity optical fibers are in demand, the problem of the fiber fuse phenomenon needs to be resolved to prevent the destruction of fibers. As polymer optical fibers become more prevalent, clarifying their fuse properties has become important. Here, we experimentally demonstrate a fuse propagation velocity of 21.9 mm/s, which is 1 to 2 orders of magnitude slower than that in standard silica fibers. The achieved threshold power density and proportionality constant between the propagation velocity and the power density are respectively 1/186 of and 16.8 times the values for silica fibers. An oscillatory continuous curve instead of periodic voids is formed after the passage of the fuse. An easy fuse termination method is presented herein, along with its potential plasma applications.

  19. Functional Use Database (FUse)

    Data.gov (United States)

    U.S. Environmental Protection Agency — There are five different files for this dataset: 1. A dataset listing the reported functional uses of chemicals (FUse) 2. All 729 ToxPrint descriptors obtained from...

  20. Joint Motion Estimation and Layer Segmentation in Transparent Image Sequences—Application to Noise Reduction in X-Ray Image Sequences

    Directory of Open Access Journals (Sweden)

    Jean Liénard

    2009-01-01

    Full Text Available This paper is concerned with the estimation of the motions and the segmentation of the spatial supports of the different layers involved in transparent X-ray image sequences. Classical motion estimation methods fail on sequences involving transparent effects since they do not explicitly model this phenomenon. We propose a method that comprises three main steps: initial block-matching for two-layer transparent motion estimation, motion clustering with 3D Hough transform, and joint transparent layer segmentation and parametric motion estimation. It is validated on synthetic and real clinical X-ray image sequences. Secondly, we derive an original transparent motion compensation method compatible with any spatiotemporal filtering technique. A direct transparent motion compensation method is proposed. To overcome its limitations, a novel hybrid filter is introduced which locally selects which type of motion compensation is to be carried out for optimal denoising. Convincing experiments on synthetic and real clinical images are also reported.

  1. Software for hyperspectral, joint photographic experts group (.JPG), portable network graphics (.PNG) and tagged image file format (.TIFF) segmentation

    Science.gov (United States)

    Bruno, L. S.; Rodrigo, B. P.; Lucio, A. de C. Jorge

    2016-10-01

    This paper presents a system developed by an application of a neural network Multilayer Perceptron for drone acquired agricultural image segmentation. This application allows a supervised user training the classes that will posteriorly be interpreted by neural network. These classes will be generated manually with pre-selected attributes in the application. After the attribute selection a segmentation process is made to allow the relevant information extraction for different types of images, RGB or Hyperspectral. The application allows extracting the geographical coordinates from the image metadata, geo referencing all pixels on the image. In spite of excessive memory consume on hyperspectral images regions of interest, is possible to perform segmentation, using bands chosen by user that can be combined in different ways to obtain different results.

  2. Survey of protocols for the manual segmentation of the hippocampus: preparatory steps towards a joint EADC-ADNI harmonized protocol.

    Science.gov (United States)

    Boccardi, Marina; Ganzola, Rossana; Bocchetta, Martina; Pievani, Michela; Redolfi, Alberto; Bartzokis, George; Camicioli, Richard; Csernansky, John G; de Leon, Mony J; deToledo-Morrell, Leyla; Killiany, Ronald J; Lehéricy, Stéphane; Pantel, Johannes; Pruessner, Jens C; Soininen, H; Watson, Craig; Duchesne, Simon; Jack, Clifford R; Frisoni, Giovanni B

    2011-01-01

    Manual segmentation from magnetic resonance imaging (MR) is the gold standard for evaluating hippocampal atrophy in Alzheimer's disease (AD). Nonetheless, different segmentation protocols provide up to 2.5-fold volume differences. Here we surveyed the most frequently used segmentation protocols in the AD literature as a preliminary step for international harmonization. The anatomical landmarks (anteriormost and posteriormost slices, superior, inferior, medial, and lateral borders) were identified from 12 published protocols for hippocampal manual segmentation ([Abbreviation] first author, publication year: [B] Bartzokis, 1998; [C] Convit, 1997; [dTM] deToledo-Morrell, 2004; [H] Haller, 1997; [J] Jack, 1994; [K] Killiany, 1993; [L] Lehericy, 1994; [M] Malykhin, 2007; [Pa] Pantel, 2000; [Pr] Pruessner, 2000; [S] Soininen, 1994; [W] Watson, 1992). The hippocampi of one healthy control and one AD patient taken from the 1.5T MR ADNI database were segmented by a single rater according to each protocol. The accuracy of the protocols' interpretation and translation into practice was checked with lead authors of protocols through individual interactive web conferences. Semantically harmonized landmarks and differences were then extracted, regarding: (a) the posteriormost slice, protocol [B] being the most restrictive, and [H, M, Pa, Pr, S] the most inclusive; (b) inclusion [C, dTM, J, L, M, Pr, W] or exclusion [B, H, K, Pa, S] of alveus/fimbria; (c) separation from the parahippocampal gyrus, [C] being the most restrictive, [B, dTM, H, J, Pa, S] the most inclusive. There were no substantial differences in the definition of the anteriormost slice. This survey will allow us to operationalize differences among protocols into tracing units, measure their impact on the repeatability and diagnostic accuracy of manual hippocampal segmentation, and finally develop a harmonized protocol.

  3. SAAS-CNV: A Joint Segmentation Approach on Aggregated and Allele Specific Signals for the Identification of Somatic Copy Number Alterations with Next-Generation Sequencing Data.

    Directory of Open Access Journals (Sweden)

    Zhongyang Zhang

    2015-11-01

    Full Text Available Cancer genomes exhibit profound somatic copy number alterations (SCNAs. Studying tumor SCNAs using massively parallel sequencing provides unprecedented resolution and meanwhile gives rise to new challenges in data analysis, complicated by tumor aneuploidy and heterogeneity as well as normal cell contamination. While the majority of read depth based methods utilize total sequencing depth alone for SCNA inference, the allele specific signals are undervalued. We proposed a joint segmentation and inference approach using both signals to meet some of the challenges. Our method consists of four major steps: 1 extracting read depth supporting reference and alternative alleles at each SNP/Indel locus and comparing the total read depth and alternative allele proportion between tumor and matched normal sample; 2 performing joint segmentation on the two signal dimensions; 3 correcting the copy number baseline from which the SCNA state is determined; 4 calling SCNA state for each segment based on both signal dimensions. The method is applicable to whole exome/genome sequencing (WES/WGS as well as SNP array data in a tumor-control study. We applied the method to a dataset containing no SCNAs to test the specificity, created by pairing sequencing replicates of a single HapMap sample as normal/tumor pairs, as well as a large-scale WGS dataset consisting of 88 liver tumors along with adjacent normal tissues. Compared with representative methods, our method demonstrated improved accuracy, scalability to large cancer studies, capability in handling both sequencing and SNP array data, and the potential to improve the estimation of tumor ploidy and purity.

  4. SAAS-CNV: A Joint Segmentation Approach on Aggregated and Allele Specific Signals for the Identification of Somatic Copy Number Alterations with Next-Generation Sequencing Data.

    Science.gov (United States)

    Zhang, Zhongyang; Hao, Ke

    2015-11-01

    Cancer genomes exhibit profound somatic copy number alterations (SCNAs). Studying tumor SCNAs using massively parallel sequencing provides unprecedented resolution and meanwhile gives rise to new challenges in data analysis, complicated by tumor aneuploidy and heterogeneity as well as normal cell contamination. While the majority of read depth based methods utilize total sequencing depth alone for SCNA inference, the allele specific signals are undervalued. We proposed a joint segmentation and inference approach using both signals to meet some of the challenges. Our method consists of four major steps: 1) extracting read depth supporting reference and alternative alleles at each SNP/Indel locus and comparing the total read depth and alternative allele proportion between tumor and matched normal sample; 2) performing joint segmentation on the two signal dimensions; 3) correcting the copy number baseline from which the SCNA state is determined; 4) calling SCNA state for each segment based on both signal dimensions. The method is applicable to whole exome/genome sequencing (WES/WGS) as well as SNP array data in a tumor-control study. We applied the method to a dataset containing no SCNAs to test the specificity, created by pairing sequencing replicates of a single HapMap sample as normal/tumor pairs, as well as a large-scale WGS dataset consisting of 88 liver tumors along with adjacent normal tissues. Compared with representative methods, our method demonstrated improved accuracy, scalability to large cancer studies, capability in handling both sequencing and SNP array data, and the potential to improve the estimation of tumor ploidy and purity.

  5. Unsupervised Multi-class Co-segmentation via Joint-Cut over L1-Manifold Hyper-Graph of Discriminative Image Regions.

    Science.gov (United States)

    Ma, Jizhou; Li, Shuai; Qin, Hong; Hao, Aimin

    2016-11-22

    This paper systematically advocates a robust and efficient unsupervised multi-class co-segmentation approach by leveraging underlying subspace manifold propagation to exploit the cross-image coherency. It can combat certain image cosegmentation difficulties due to viewpoint change, partial occlusion, complex background, transient illumination, and cluttering texture patterns. Our key idea is to construct a powerful hyper-graph joint-cut framework, which incorporates mid-level image regions based intra-image feature representation and L1- manifold graph based inter-image coherency exploration. For local image region generation, we propose a bi-harmonic distance distribution difference metric to govern the super-pixel clustering in a bottom-up way. It not only affords drastic data reduction but also gives rise to discriminative and structure-meaningful feature representation. As for the inter-image coherency, we leverage multi-type features involved L1-graph to detect the underlying local manifold from cross-image regions. As a result, the implicit supervising information could be encoded into the unsupervised hyper-graph joint-cut framework. We conduct extensive experiments and make comprehensive evaluations with other stateof- the-art methods over various benchmarks, including iCoseg, MSRC, and Oxford flower. All the results demonstrate the superiorities of our method in terms of accuracy, robustness, efficiency, and versatility.

  6. 融合多尺度分割与CART算法的矸石山提取%Fusing muti-scale segmentation into CART algorithm on coal gangue extraction

    Institute of Scientific and Technical Information of China (English)

    赵慧; 汪云甲

    2012-01-01

    结合多尺度分割和CART算法的特性,提出一种新的目标信息提取方法.其基本思想是将小尺度分割与大尺度分割相结合,将影像分割成一系列同质性对象;以同质性对象为基本单元选择训练样本,后利用CART算法提取目标信息.实验结果表明:与单纯像素级的CART算法相比,该方法可有效减少提取结果的噪声,一定程度上排除了其他地类对目标信息的干扰,提取精度显著提高.%Considering the properties of muti-scale segmentation and CART, a method for information extraction is proposed in this paper. Integrating small-scale segmentation with big-scale segmentation, the remote sensing image is segmented into a series of homogenous regions through watershed transformation and region merging process. The region-based information extraction is performed by utilizing CART after sample selection. Experimental results indicate that the proposed information extraction method depresses the image noise effectively, the extraction accuracy is improved and more interpretable result can also be achieved.

  7. Lumbo-pelvic joint protection against antigravity forces: motor control and segmental stiffness assessed with magnetic resonance imaging.

    Science.gov (United States)

    Richardson, C A; Hides, J A; Wilson, S; Stanton, W; Snijders, C J

    2004-07-01

    The antigravity muscles of the lumbo-pelvic region, especially transversus abdominis (TrA), are important for the protection and support of the weightbearing joints. Measures of TrA function (the response to the postural cue of drawing in the abdominal wall) have been developed and quantified using magnetic resonance imaging (MRI). Cross-sections through the trunk allowed muscle contraction as well as the large fascial attachments of the TrA to be visualized. The cross sectional area (CSA) of the deep musculo-fascial system was measured at rest and in the contracted state, using static images as well as a cine sequence. In this developmental study, MRI measures were undertaken on a small sample of low back pain (LBP) and non LBP subjects. Results demonstrated that, in non LBP subjects, the draw in action produced a symmetrical deep musculo-fascial "corset" which encircles the abdomen. This study demonstrated a difference in this "corset" measure between subjects with and without LBP. These measures may also prove useful to quantify the effect of unloading in bedrest and microgravity exposure.

  8. Beyond Chandra (towards the X-ray Surveyor mission): possible solutions for the implementation of very high angular resolution X-ray telescopes in the new millennium based on fused silica segments

    Science.gov (United States)

    Pareschi, G.; Basso, S.; Civitani, M. M.; Ghigo, M.; Parodi, G.; Pelliciari, C.; Salmaso, B.; Spiga, D.; Vecchi, G.

    2016-07-01

    An important challenge for the X-ray astronomy of the new millennium is represented by the implementation of an Xray telescope able to maintain the exquisite angular resolution of Chandra (with a sub-arcsec HEW, on-axis) but, at the same time, being characterized by a much larger throughput and grasp. A mission with similar characteristics is represented by the X-ray Surveyor Mission. The project has been recently proposed in USA and is being currently studied by NASA. It will host an X-ray telescope with an effective area of more than 2 square meters at 1 keV (i.e. 30 times greater than Chandra) and a 15-arcminutes field-of-view, with 1-arcsecond or better half-power diameter (versus the 4 arcmin diameter of Chandra). While the scientific reasons for implementing a similar mission are clear, being related to compelling problems like e.g. the formation and subsequent growth of black hole seeds at very high redshift or the identification of the first galaxy groups and proto-clusters, the realization of a grazing-angle optics system able to fulfil these specs remain highly challenging. Different technologies are being envisaged, like e.g. the use of adjustable segmented mirrors (with use of piezoelectric or magneto-restrictive film actuators on the back surface) or the direct polishing of a variety of thin substrates or the use of innovative correction methods like e.g. differential deposition, ionfiguring or the correction of the profile via controlled stress films. In this paper we present a possible approach based on the direct polishing (with final ion figuring correction of the profile) of thin SiO2 segmented substrates (typically 2 mm thick), discussing different aspects of the technology under implementation and presenting some preliminary results.

  9. Spacesuit mobility knee joints

    Science.gov (United States)

    Vykukal, H. C. (Inventor)

    1979-01-01

    Pressure suit mobility joints are for use in interconnecting adjacent segments of an hermetically sealed spacesuit in which low torques, low leakage and a high degree of reliability are required. Each of the joints is a special purpose joint characterized by substantially constant volume and low torque characteristics and includes linkages which restrain the joint from longitudinal distension and includes a flexible, substantially impermeable diaphragm of tubular configuration spanning the distance between pivotally supported annuli. The diaphragms of selected joints include rolling convolutions for balancing the joints, while various joints include wedge-shaped sections which enhance the range of motion for the joints.

  10. Fused-Polished Fiber Couplers

    Institute of Scientific and Technical Information of China (English)

    Sien; Chi; Shiao-Min; Tseng

    2003-01-01

    We report on fused-polished fiber couplers with a new fabrication method. This structure so fabricated is promising while achieving high-performance all-fiber WDM devices. Potential advantages and prospects of our works are presented.

  11. Thermal fatigue of electrical fuses

    Directory of Open Access Journals (Sweden)

    Gelet Jean-Louis

    2014-06-01

    Full Text Available Electric Fuses have to respect different national or international standards such as IEC (International Electro-technical Commission 269. These standards define the characteristics of the fuses and describe the tests to be run in order to check fuse's ability to take up their main functions, i.e. current-conduction and operation under overloads and short-circuits. But fuses never carry current neither operate under standardized conditions. For example, rated current is evaluated under specified ambient temperature, without cooling air-flow, and with 1 meter-long connection-cables on both sides. In the field, temperature can reach up 80∘C, with or without air-flow and connection-parts are much more shorter. An issue is that current is never constant, often being cyclingly applied; equipments are frequently in use during the day and stopped in the night. ON-time and OFF-time generate alternative heating, then alternative stresses leading to thermal fatigue. MERSEN run many tests along the years, allowing to develop a method for choosing right fuses for each application. As a result, fuses don't melt unexpectedly in the field, but the method is supposed to be conservative and does not permit to get a better understanding of the phenomena neither an improvement of the products. The paper presents some specific ageing-tests run on conductive elements and tries to establish a correspondence between these tests and others carried out on complete fuses. Tests have been run on silver and copper, but their principle could be interesting for any structural material, especially because it underlines crack-opening.

  12. Market Segmentation of Air Passenger Transport Based on Joint Algorithm of Hierarchy Clustering and FCM%基于层次聚类 FCM 算法的航空客运市场细分

    Institute of Scientific and Technical Information of China (English)

    王悦; 曾小舟; 傅骏

    2015-01-01

    运用层次聚类法和FCM算法,从Kotler四维顾客价值角度构建航空客运市场细分量表,形成施测问卷,获取样本数据。将因子分析与基于层次聚类的FCM算法相结合,获得4类差距明显的子市场,并验证了市场细分的有效性。研究结果表明,基于层次聚类的FCM算法细分航空客运市场能够获得较为满意的结果,也验证了该混合算法的合理性、有效性和可操作性,其中细分量表与基于层次聚类的FCM算法可作为航空客运主体细分市场的依据和方法。%Combining the strengths of the hierarchy clustering method and the fuzzy c -means ( FCM) algorithm, the practi-cal issue of the market segmentation ( MS) of the air passenger transport was analyzed .The market segmentation scale for the air passenger transport was constructed from the Kotler's four-dimensional customer value ( CV) .On the basis of the scale , a ques-tionnaire was formed and the correspondent data were collected .Combining the factor analysis and the joint algorithm of hierarchy clustering and FCM , four segmented markets with significant differences were finally obtained .The mean value analysis and the variance analysis were applied to verify the effectiveness of the result .The results demonstrate that by applying the joint algorithm of hierarchy clustering and FCM , combining Kotler's four-dimensional CV , the market of air passenger transport could be desira-bly segmented.In turn, the results also confirm the feasibility and reasonableness of the joint algorithm .The market segmentation scale and the joint algorithm can be utilized for the MS for the operational subjects in civil aviation .

  13. Magnetic resonance imaging analysis and Fisher's linearity discrimination for the selection of fixed and fused segments during treatment of degenerative low lumbar spinal diseases%MRI影像学测量分析及Fisher's线性判别在退变性下腰椎固定融合节段选择中的意义

    Institute of Scientific and Technical Information of China (English)

    杨振东; 解京明; 王迎松; 张颖

    2011-01-01

    BACKGROUND: Studies addressing MRI data and treated segment selection during the treatment of senile lumbar degenerative diseases are rare.OBJECTIVE: To investigate the clinical significance of the MRI in the selection of fixed and fused segments for treatment of degenerative low lumbar spinal diseases in the elderly.METHODS: The clinical data of 152 patients with lumbar degenerative diseases were divided into two groups: operation group and control group. They were followed up for 3, 6, 12, 24 months post treatment. Clinical function of pre and post-treatment of all the cases were determined by using Japanese Orthopaedic Association (JOA) score. The JOA score between the operation group and control group was compared. And using discriminate analysis, we studied the change of MRI, tried to find out the clinical significance of MRI in the selection of treated segment during the treatment of degenerative low lumbar spinal diseases.RESULTS AND CONCLUSION: JOA score was significantly improved post operation in the operation group (P < 0.05).Compared to the control group, JOA score was significantly higher in the operation group (P < 0.05). Discriminant Functions were established depending on the analysis of clinical and imaging information by using statistical software, and proved whose have statistical significance. Discriminant functions were effective to distinguish degenerative low lumbar spinal diseases and institute individualization operation project and choice possible treated segment and gain all-right clinical outcome.%背景:对下腰椎退变的MRI资料与老年人下腰椎退变性疾患中治疗节段选择的相关性报道较少.目的:分析MRI对老年人下腰椎退变性疾病中固定融合节段选择的临床指导意义.方法:选择152例退变性腰椎疾病患者,根据治疗方案分为对照组及固定融合组,对照组47例采用保守治疗,固定融合组105例均采用经腰椎后路全椎板减压、固定

  14. Electric field theory based approach to search-direction line definition in image segmentation: application to optimal femur-tibia cartilage segmentation in knee-joint 3-D MR

    Science.gov (United States)

    Yin, Y.; Sonka, M.

    2010-03-01

    A novel method is presented for definition of search lines in a variety of surface segmentation approaches. The method is inspired by properties of electric field direction lines and is applicable to general-purpose n-D shapebased image segmentation tasks. Its utility is demonstrated in graph construction and optimal segmentation of multiple mutually interacting objects. The properties of the electric field-based graph construction guarantee that inter-object graph connecting lines are non-intersecting and inherently covering the entire object-interaction space. When applied to inter-object cross-surface mapping, our approach generates one-to-one and all-to-all vertex correspondent pairs between the regions of mutual interaction. We demonstrate the benefits of the electric field approach in several examples ranging from relatively simple single-surface segmentation to complex multiobject multi-surface segmentation of femur-tibia cartilage. The performance of our approach is demonstrated in 60 MR images from the Osteoarthritis Initiative (OAI), in which our approach achieved a very good performance as judged by surface positioning errors (average of 0.29 and 0.59 mm for signed and unsigned cartilage positioning errors, respectively).

  15. Liquefier Dynamics in Fused Deposition

    DEFF Research Database (Denmark)

    Bellini, Anna; Guceri, Selcuk; Bertoldi, Maurizio

    2004-01-01

    Layered manufacturing (LM) is an evolution of rapid prototyping (RP) technology whereby a part is built in layers. Fused deposition modeling (FDM) is a particular LM technique in which each section is fabricated through vector style deposition of building blocks, called roads, which...

  16. An algorithm for segmenting range imagery

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, R.S.

    1997-03-01

    This report describes the technical accomplishments of the FY96 Cross Cutting and Advanced Technology (CC&AT) project at Los Alamos National Laboratory. The project focused on developing algorithms for segmenting range images. The image segmentation algorithm developed during the project is described here. In addition to segmenting range images, the algorithm can fuse multiple range images thereby providing true 3D scene models. The algorithm has been incorporated into the Rapid World Modelling System at Sandia National Laboratory.

  17. Cluster Ensemble-based Image Segmentation

    OpenAIRE

    Xiaoru Wang; Junping Du; Shuzhe Wu; Xu Li; Fu Li

    2013-01-01

    Image segmentation is the foundation of computer vision applications. In this paper, we propose a new cluster ensemble-based image segmentation algorithm, which overcomes several problems of traditional methods. We make two main contributions in this paper. First, we introduce the cluster ensemble concept to fuse the segmentation results from different types of visual features effectively, which can deliver a better final result and achieve a much more stable performance for broad categories ...

  18. Musculo-tendinous stiffness of head-neck segment in the sagittal plane: an optimization approach for modeling the cervical spine as a single-joint system.

    Science.gov (United States)

    Portero, Raphaël; Quaine, Franck; Cahouet, Violaine; Thoumie, Philippe; Portero, Pierre

    2013-03-15

    Despite the multi-linked architecture of the cervical spine, all previous studies that have made estimations of mechanical properties of the neck have considered the head-neck segment as a rigid link, with a fixed center of rotation at C7. The aim of this study was to consider the head-neck segment as a changeable geometry system for locating the resultant center of rotation and for calculating the musculo-tendinous stiffness by the quick-release method. Head kinematics during quick-releases was analyzed by recording the trajectory of surface markers. With an optimization procedure, the position of the resultant center of rotation of the head-neck segment was estimated. Thereafter, the angular displacement and acceleration of the head, together with the isometric torque developed by the cervical muscles were used to calculate the segment's stiffness. The results showed a consistent center of rotation and a significant increase of the musculo-tendinous stiffness with increasing torque. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Automatic lung tumor segmentation on PET/CT images using fuzzy Markov random field model.

    Science.gov (United States)

    Guo, Yu; Feng, Yuanming; Sun, Jian; Zhang, Ning; Lin, Wang; Sa, Yu; Wang, Ping

    2014-01-01

    The combination of positron emission tomography (PET) and CT images provides complementary functional and anatomical information of human tissues and it has been used for better tumor volume definition of lung cancer. This paper proposed a robust method for automatic lung tumor segmentation on PET/CT images. The new method is based on fuzzy Markov random field (MRF) model. The combination of PET and CT image information is achieved by using a proper joint posterior probability distribution of observed features in the fuzzy MRF model which performs better than the commonly used Gaussian joint distribution. In this study, the PET and CT simulation images of 7 non-small cell lung cancer (NSCLC) patients were used to evaluate the proposed method. Tumor segmentations with the proposed method and manual method by an experienced radiation oncologist on the fused images were performed, respectively. Segmentation results obtained with the two methods were similar and Dice's similarity coefficient (DSC) was 0.85 ± 0.013. It has been shown that effective and automatic segmentations can be achieved with this method for lung tumors which locate near other organs with similar intensities in PET and CT images, such as when the tumors extend into chest wall or mediastinum.

  20. Automatic Lung Tumor Segmentation on PET/CT Images Using Fuzzy Markov Random Field Model

    Directory of Open Access Journals (Sweden)

    Yu Guo

    2014-01-01

    Full Text Available The combination of positron emission tomography (PET and CT images provides complementary functional and anatomical information of human tissues and it has been used for better tumor volume definition of lung cancer. This paper proposed a robust method for automatic lung tumor segmentation on PET/CT images. The new method is based on fuzzy Markov random field (MRF model. The combination of PET and CT image information is achieved by using a proper joint posterior probability distribution of observed features in the fuzzy MRF model which performs better than the commonly used Gaussian joint distribution. In this study, the PET and CT simulation images of 7 non-small cell lung cancer (NSCLC patients were used to evaluate the proposed method. Tumor segmentations with the proposed method and manual method by an experienced radiation oncologist on the fused images were performed, respectively. Segmentation results obtained with the two methods were similar and Dice’s similarity coefficient (DSC was 0.85 ± 0.013. It has been shown that effective and automatic segmentations can be achieved with this method for lung tumors which locate near other organs with similar intensities in PET and CT images, such as when the tumors extend into chest wall or mediastinum.

  1. Research on joint Chinese-Japanese word segmentation for phrase-based statistical machine translation%面向短语统计机器翻译的汉日联合分词研究

    Institute of Scientific and Technical Information of China (English)

    吴培昊; 徐金安; 张玉洁

    2015-01-01

    Unknown words and word segmentation granularity are two main problems for Chinese-Japanese machine translation. Word segmentation is the first important step for Chinese and Japanese natural language processing. As Chi-nese and Japanese word segmentation is processed with different tagging system and semantic performance, the granularity of word segmentation results should be readjusted to improve the performance of Statistical Machine Translation(SMT). This paper proposes an approach to adjust the word segmentation granularity for improving the performance of SMT, which combines Hanzi-Kanji comparison table and Japanese-Chinese dictionary. Experimental results express that the pro-posed method could adjust the granularity between Chinese and Japanese effectively and improve the performance of SMT. This paper analyses the experimental results and discusses the effect of joint Chinese-Japanese word segmentation granularity for phrase-based SMT.%未登录词与分词粒度是汉日日汉机器翻译研究的两个主要问题。与英语等西方语言不同,汉语与日语词语间不存在空格,分词为汉日双语处理的重要工作。由于词性标注体系、文法及语义表现上的差异,分词结果的粒度需要进一步调整,以改善统计机器翻译系统的性能。提出了面向统计机器翻译的基于汉日汉字对照表及日汉词典信息的汉语与日语的分词粒度调整方法。实验结果表明,该方法能有效地调节源语言和目标语言端的分词粒度,提高统计机器翻译系统的性能。通过对比实验结果,分析探讨分词粒度对汉日双语统计系统性能的影响。

  2. Fusing Depth and Silhouette for Scanning Transparent Object with RGB-D Sensor

    Directory of Open Access Journals (Sweden)

    Yijun Ji

    2017-01-01

    Full Text Available 3D reconstruction based on structured light or laser scan has been widely used in industrial measurement, robot navigation, and virtual reality. However, most modern range sensors fail to scan transparent objects and some other special materials, of which the surface cannot reflect back the accurate depth because of the absorption and refraction of light. In this paper, we fuse the depth and silhouette information from an RGB-D sensor (Kinect v1 to recover the lost surface of transparent objects. Our system is divided into two parts. First, we utilize the zero and wrong depth led by transparent materials from multiple views to search for the 3D region which contains the transparent object. Then, based on shape from silhouette technology, we recover the 3D model by visual hull within these noisy regions. Joint Grabcut segmentation is operated on multiple color images to extract the silhouette. The initial constraint for Grabcut is automatically determined. Experiments validate that our approach can improve the 3D model of transparent object in real-world scene. Our system is time-saving, robust, and without any interactive operation throughout the process.

  3. Flight test investigation of the vortex wake characteristics behind a Boeing 727 during two-segment and normal ILS approaches (A joint NASA/FAA report)

    Science.gov (United States)

    Barber, M. R.; Kurkowski, R. L.; Garodz, L. J.; Robinson, G. H.; Smith, H. J.; Jacobsen, R. A.; Stinnett, G. W., Jr.; Mcmurtry, T. C.; Tymczyszyn, J. J.; Devereaux, R. L.

    1975-01-01

    Flight tests were performed to evaluate the vortex wake characteristics of a Boeing 727 aircraft during conventional and two-segment instrument landing approaches. Smoke generators were used for vortex marking. The vortex was intentionally intercepted by a Lear Jet and a Piper Comanche aircraft. The vortex location during landing approach was measured using a system of phototheodolites. The tests showed that at a given separation distance there are no readily apparent differences in the upsets resulting from deliberate vortex encounters during the two types of approaches. The effect of the aircraft configuration on the extent and severity of the vortices is discussed.

  4. Influenza a virus assembly intermediates fuse in the cytoplasm.

    Directory of Open Access Journals (Sweden)

    Seema S Lakdawala

    2014-03-01

    Full Text Available Reassortment of influenza viral RNA (vRNA segments in co-infected cells can lead to the emergence of viruses with pandemic potential. Replication of influenza vRNA occurs in the nucleus of infected cells, while progeny virions bud from the plasma membrane. However, the intracellular mechanics of vRNA assembly into progeny virions is not well understood. Here we used recent advances in microscopy to explore vRNA assembly and transport during a productive infection. We visualized four distinct vRNA segments within a single cell using fluorescent in situ hybridization (FISH and observed that foci containing more than one vRNA segment were found at the external nuclear periphery, suggesting that vRNA segments are not exported to the cytoplasm individually. Although many cytoplasmic foci contain multiple vRNA segments, not all vRNA species are present in every focus, indicating that assembly of all eight vRNA segments does not occur prior to export from the nucleus. To extend the observations made in fixed cells, we used a virus that encodes GFP fused to the viral polymerase acidic (PA protein (WSN PA-GFP to explore the dynamics of vRNA assembly in live cells during a productive infection. Since WSN PA-GFP colocalizes with viral nucleoprotein and influenza vRNA segments, we used it as a surrogate for visualizing vRNA transport in 3D and at high speed by inverted selective-plane illumination microscopy. We observed cytoplasmic PA-GFP foci colocalizing and traveling together en route to the plasma membrane. Our data strongly support a model in which vRNA segments are exported from the nucleus as complexes that assemble en route to the plasma membrane through dynamic colocalization events in the cytoplasm.

  5. About a New Type of Fuse Based on the Controllable Fusing Effect

    Directory of Open Access Journals (Sweden)

    PLESCA, A.

    2009-06-01

    Full Text Available Fuses are among the best known of electrical devices and there are an extremely large number in use throughout the world. Beside of the advantageous features, the nowadays fuses have certain drawbacks. Therefore, a new type of fuse based on controllable fusing concept is proposed and a study as regards the total clearing time is done. The new concept has been validated through many experimental tests at different current values. The new type of fuse based on controllable fusing concept can be integrated within an overcurrent protection system especially to protect power semiconductors where the Joule integral criterion is better satisfied.

  6. A method to investigate the effect of shoe-hole size on surface marker movement when describing in-shoe joint kinematics using a multi-segment foot model.

    Science.gov (United States)

    Bishop, Chris; Arnold, John B; Fraysse, Francois; Thewlis, Dominic

    2015-01-01

    To investigate in-shoe foot kinematics, holes are often cut in the shoe upper to allow markers to be placed on the skin surface. However, there is currently a lack of understanding as to what is an appropriate size. This study aimed to demonstrate a method to assess whether different diameter holes were large enough to allow free motion of marker wands mounted on the skin surface during walking using a multi-segment foot model. Eighteen participants underwent an analysis of foot kinematics whilst walking barefoot and wearing shoes with different size holes (15 mm, 20mm and 25 mm). The analysis was conducted in two parts; firstly the trajectory of the individual skin-mounted markers were analysed in a 2D ellipse to investigate total displacement of each marker during stance. Secondly, a geometrical analysis was conducted to assess cluster deformation of the hindfoot and midfoot-forefoot segments. Where movement of the markers in the 15 and 20mm conditions were restricted, the marker movement in the 25 mm condition did not exceed the radius at any anatomical location. Despite significant differences in the isotropy index of the medial and lateral calcaneus markers between the 25 mm and barefoot conditions, the differences were due to the effect of footwear on the foot and not a result of the marker wands hitting the shoe upper. In conclusion, the method proposed and results can be used to increase confidence in the representativeness of joint kinematics with respect to in-shoe multi-segment foot motion during walking.

  7. Dynamic simulation of flywheel-type fuses

    OpenAIRE

    Editorial Office

    1996-01-01

    Rounds of ammunition are normally armed with a fuse. In this study, a fuse is developed which uses a flywheel-type mechanism controlled by time or distance. Due to its simplicity of operation and construction, the concept is expected to have high reliabil­ity. The dynamic response of all the components of this flywheel-type fuse is mathematically modelled. Simulation software was developed which connects the mathematical models of the various components. With the definition of boundary value...

  8. FUSE Observations of eta Carinae

    CERN Document Server

    Iping, R C; Gull, T R

    2004-01-01

    Eta Carinae was observed by FUSE through the LWRS (30 arcsec x30 arcsec) and HIRS (1.25 arcsec x 20 arcsec) apertures in March and April 2004. There are significant differences between the two spectra. About half of the LWRS flux appears to be due to two B-type stars near the edge of the LWRS aperture, 14 arcsec from eta Carinae. The HIRS spectrum (LiF1 channel) therefore reveals the intrinsic FUV spectrum of eta Carinae without this stellar contamination. The HIRS spectrum contains strong interstellar H2 having high rotational excitation (up to J=8). Most of the atomic species with prominent ISM features (C II, Fe II, Ar I, P II, etc) also have strong blue-shifted absorption to v= ~ -580 km/s that is associated with expanding debris from the 1840 eruption.

  9. Isolated bilateral transverse agenesis of the distal segments of the lower limbs at the level of the knee joint in a human fetus.

    Science.gov (United States)

    Christiaens, Antoine B; Deprez, Pierre M L; Amyere, Mustapha; Mendola, Antonella; Bernard, Pierre; Gillerot, Yves; Clapuyt, Philippe; Godfraind, Catherine; Lengelé, Benoît G; Vikkula, Miikka; Nyssen-Behets, Catherine

    2016-02-01

    Congenital limb anomalies occur in Europe with a prevalence of 3.81/1,000 births and can have a major impact on patients and their families. The present study concerned a female fetus aborted at 23 weeks of gestation because she was affected by non-syndromic bilateral absence of the zeugopod (leg) and autopod (foot). Autopsy of the aborted fetus, X-ray imaging, MRI, and histochemical analysis showed that the distal extremity of both femurs was continued by a cartilage-like mass, without joint cavitation. Karyotype was normal. Moreover, no damaging variant was detected by exome sequencing. The limb characteristics of the fetus, which to our knowledge have not yet been reported in humans, suggest a developmental arrest similar to anomalies described in chicks following surgical experiments on the apical ectodermal ridge of the lower limbs.

  10. Segmentation: Identification of consumer segments

    DEFF Research Database (Denmark)

    Høg, Esben

    2005-01-01

    It is very common to categorise people, especially in the advertising business. Also traditional marketing theory has taken in consumer segments as a favorite topic. Segmentation is closely related to the broader concept of classification. From a historical point of view, classification has its...... and analysed possible segments in the market. Results show that the statistical model used identified two segments - a segment of so-called "fish lovers" and another segment called "traditionalists". The "fish lovers" are very fond of eating fish and they actually prefer fish to other dishes...... origin in other sciences as for example biology, anthropology etc. From an economic point of view, it is called segmentation when specific scientific techniques are used to classify consumers to different characteristic groupings. What is the purpose of segmentation? For example, to be able to obtain...

  11. Fused combiners for photonic crystal bers

    DEFF Research Database (Denmark)

    Noordegraaf, Danny

    The work presented in this Ph.D. thesis focuses on the fabrication of fused combiners for high-power fiber lasers and amplifiers. The main focus of the Ph.D. project was to further develop the fused pump combiners for airclad photonic crystal bers (PCFs), and implement a signal feed...

  12. Automated analysis of non-mass-enhancing lesions in breast MRI based on morphological, kinetic, and spatio-temporal moments and joint segmentation-motion compensation technique

    Science.gov (United States)

    Hoffmann, Sebastian; Shutler, Jamie D.; Lobbes, Marc; Burgeth, Bernhard; Meyer-Bäse, Anke

    2013-12-01

    Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) represents an established method for the detection and diagnosis of breast lesions. While mass-like enhancing lesions can be easily categorized according to the Breast Imaging Reporting and Data System (BI-RADS) MRI lexicon, a majority of diagnostically challenging lesions, the so called non-mass-like enhancing lesions, remain both qualitatively as well as quantitatively difficult to analyze. Thus, the evaluation of kinetic and/or morphological characteristics of non-masses represents a challenging task for an automated analysis and is of crucial importance for advancing current computer-aided diagnosis (CAD) systems. Compared to the well-characterized mass-enhancing lesions, non-masses have no well-defined and blurred tumor borders and a kinetic behavior that is not easily generalizable and thus discriminative for malignant and benign non-masses. To overcome these difficulties and pave the way for novel CAD systems for non-masses, we will evaluate several kinetic and morphological descriptors separately and a novel technique, the Zernike velocity moments, to capture the joint spatio-temporal behavior of these lesions, and additionally consider the impact of non-rigid motion compensation on a correct diagnosis.

  13. Laser welding of fused quartz

    Science.gov (United States)

    Piltch, Martin S.; Carpenter, Robert W.; Archer, III, McIlwaine

    2003-06-10

    Refractory materials, such as fused quartz plates and rods are welded using a heat source, such as a high power continuous wave carbon dioxide laser. The radiation is optimized through a process of varying the power, the focus, and the feed rates of the laser such that full penetration welds may be accomplished. The process of optimization varies the characteristic wavelengths of the laser until the radiation is almost completely absorbed by the refractory material, thereby leading to a very rapid heating of the material to the melting point. This optimization naturally occurs when a carbon dioxide laser is used to weld quartz. As such this method of quartz welding creates a minimum sized heat-affected zone. Furthermore, the welding apparatus and process requires a ventilation system to carry away the silicon oxides that are produced during the welding process to avoid the deposition of the silicon oxides on the surface of the quartz plates or the contamination of the welds with the silicon oxides.

  14. Porphyrins Fused with Unactivated Polycyclic Aromatic Hydrocarbons

    KAUST Repository

    Diev, Vyacheslav V.

    2012-01-06

    A systematic study of the preparation of porphyrins with extended conjugation by meso,β-fusion with polycyclic aromatic hydrocarbons (PAHs) is reported. The meso-positions of 5,15-unsubstituted porphyrins were readily functionalized with PAHs. Ring fusion using standard Scholl reaction conditions (FeCl 3, dichloromethane) occurs for perylene-substituted porphyrins to give a porphyrin β,meso annulated with perylene rings (0.7:1 ratio of syn and anti isomers). The naphthalene, pyrene, and coronene derivatives do not react under Scholl conditions but are fused using thermal cyclodehydrogenation at high temperatures, giving mixtures of syn and anti isomers of the meso,β-fused porphyrins. For pyrenyl-substituted porphyrins, a thermal method gives synthetically acceptable yields (>30%). Absorption spectra of the fused porphyrins undergo a progressive bathochromic shift in a series of naphthyl (λ max = 730 nm), coronenyl (λ max = 780 nm), pyrenyl (λ max = 815 nm), and perylenyl (λ max = 900 nm) annulated porphyrins. Despite being conjugated with unsubstituted fused PAHs, the β,meso-fused porphyrins are more soluble and processable than the parent nonfused precursors. Pyrenyl-fused porphyrins exhibit strong fluorescence in the near-infrared (NIR) spectral region, with a progressive improvement in luminescent efficiency (up to 13% with λ max = 829 nm) with increasing degree of fusion. Fused pyrenyl-porphyrins have been used as broadband absorption donor materials in photovoltaic cells, leading to devices that show comparatively high photovoltaic efficiencies. © 2011 American Chemical Society.

  15. Vehicle License Plate Character Segmentation

    Institute of Scientific and Technical Information of China (English)

    Mei-Sen Pan; Jun-Biao Yan; Zheng-Hong Xiao

    2008-01-01

    Vehicle license plate (VLP) character segmentation is an important part of the vehicle license plate recognition system (VLPRS). This paper proposes a least square method (LSM) to treat horizontal tilt and vertical tilt in VLP images. Auxiliary lines are added into the image (or the tilt-corrected image) to make the separated parts of each Chinese character to be an interconnected region. The noise regions will be eliminated after two fusing images are merged according to the minimum principle of gray values.Then, the characters are segmented by projection method (PM) and the final character images are obtained. The experimental results show that this method features fast processing and good performance in segmentation.

  16. Dynamic simulation of flywheel-type fuses

    Directory of Open Access Journals (Sweden)

    Editorial Office

    1996-07-01

    Full Text Available Rounds of ammunition are normally armed with a fuse. In this study, a fuse is developed which uses a flywheel-type mechanism controlled by time or distance. Due to its simplicity of operation and construction, the concept is expected to have high reliabil­ity. The dynamic response of all the components of this flywheel-type fuse is mathematically modelled. Simulation software was developed which connects the mathematical models of the various components. With the definition of boundary values, the response of the projectile, flywheel and other components can be determined continuously for firing and in-flight conditions.

  17. Predictive parameters for the antecedent development of hip pathology associated with long segment fusions to the pelvis for the treatment of adult spinal deformity

    Directory of Open Access Journals (Sweden)

    Merritt D Kinon

    2016-01-01

    Full Text Available Background: The surgical treatment of adult scoliosis frequently involves long segment fusions across the lumbosacral joints that redistribute tremendous amounts of force to the remaining mobile spinal segments as well as to the pelvis and hip joints. Whether or not these forces increase the risk of femoral bone pathology remains unknown. The aim of this study is to determine the correlation between long segment spinal fusions to the pelvis and the antecedent development of degenerative hip pathologies as well as what predictive patient characteristics, if any, correlate with their development. Methods: A retrospective chart review of all long segment fusions to the pelvis for adult degenerative deformity operated on by the senior author at the Duke Spine Center from February 2008 to March 2014 was undertaken. Enrolment criteria included all available demographic, surgical, and clinical outcome data as well as pre and postoperative hip pathology assessment. All patients had prospectively collected outcome measures and a minimum 2-year follow-up. Multivariable logistic regression analysis was performed comparing the incidence of preoperative hip pain and antecedent postoperative hip pain as a function of age, gender, body mass index (BMI, and number of spinal levels fused. Results: In total, 194 patients were enrolled in this study. Of those, 116 patients (60% reported no hip pain prior to surgery. Eighty-three patients (71.6% remained hip pain free, whereas 33 patients (28.5% developed new postoperative hip pain. Age, gender, and BMI were not significant among those who went on to develop hip pain postoperatively (P < 0.0651, 0.3491, and 0.1021, respectively. Of the 78 patients with preoperative hip pain, 20 patients (25.6% continued to have hip pain postoperatively, whereas 58 patients reported improvement in the hip pain after long segment fusion for correction of their deformity, a 74.4% rate of reduction. Age, gender, and BMI were not

  18. Coordination chemistry in fused-salt solutions

    Science.gov (United States)

    Gruen, D. M.

    1969-01-01

    Spectrophotometric work on structural determinations with fused-salt solutions is reviewed. Constraints placed on the method, as well as interpretation of the spectra, are discussed with parallels drawn to aqueous spectrophotometric curves of the same materials.

  19. Fuse Protects Parabolic-Dish Solar Collector

    Science.gov (United States)

    Selcuk, M. K.

    1983-01-01

    Sliding barrel and shutter protect against overheating. Downward movement of shutter initiated by melting of fuse wire that suspends it. Shutter lowered or raised under operator's control by depressuring or pressurizing hydraulic cylinder.

  20. Organometallic chemistry: Fused ferrocenes come full circle

    Science.gov (United States)

    Musgrave, Rebecca A.; Manners, Ian

    2016-09-01

    Chemists have long been fascinated by electron delocalization, from both a fundamental and applied perspective. Macrocyclic oligomers containing fused ferrocenes provide a new structural framework -- containing strongly interacting metal centres -- that is capable of supporting substantial charge delocalization.

  1. Facade model refinement by fusing terrestrial laser data and image

    Science.gov (United States)

    Liu, Yawen; Qin, Sushun

    2015-12-01

    The building facade model is one of main landscapes of a city and basic data of city geographic information. It is widely useful in accurate path planning, real navigation through the urban environment, location-based application, etc. In this paper, a method of facade model refinement by fusing terrestrial laser data and image is presented. It uses the matching of model edge and image line combined with laser data verification and effectively refines facade geometry model that reconstructed from laser data. The laser data of geometric structures on building facade such as window, balcony and door are segmented, and used as a constraint for further selecting the optical model edges that are located at the cross-line of point data and no data. The results demonstrate the deviation of model edges caused by laser sampling interval can be removed in the proposed method.

  2. The effect of different design concepts in lumbar total disc arthroplasty on the range of motion, facet joint forces and instantaneous center of rotation of a L4-5 segment.

    Science.gov (United States)

    Schmidt, Hendrik; Midderhoff, Stefan; Adkins, Kyle; Wilke, Hans-Joachim

    2009-11-01

    Although both unconstrained and constrained core lumbar artificial disc designs are in clinical use, the effect of their design on the range of motion, center of rotations, and facet joint forces is not well understood. It is assumed that the constrained configuration causes a fixed center of rotation with high facet forces, while the unconstrained configuration leads to a moving center of rotation with lower loaded facets. The authors disagree with both assumptions and hypothesized that the two different designs do not lead to substantial differences in the results. For the different implant designs, a three-dimensional finite element model was created and subsequently inserted into a validated model of a L4-5 lumbar spinal segment. The unconstrained design was represented by two implants, the Charité disc and a newly developed disc prosthesis: Slide-Disc. The constrained design was obtained by a modification of the Slide-Disc whereby the inner core was rigidly connected to the lower metallic endplate. The models were exposed to an axial compression preload of 1,000 N. Pure unconstrained moments of 7.5 Nm were subsequently applied to the three anatomical main planes. Except for extension, the models predicted only small and moderate inter-implant differences. The calculated values were close to those of the intact segment. For extension, a large difference of about 45% was calculated between both Slide-Disc designs and the Charité disc. The models predicted higher facet forces for the implants with an unconstrained core compared to an implant with a constrained core. All implants caused a moving center of rotation. Except for axial rotation, the unconstrained and constrained configurations mimicked the intact situation. In axial rotation, only the Slide- Disc with mobile core reproduced the intact behavior. Results partially support our hypothesis and imply that different implant designs do not lead to strong differences in the range of motion and the location

  3. Fingerprint Segmentation

    OpenAIRE

    Jomaa, Diala

    2009-01-01

    In this thesis, a new algorithm has been proposed to segment the foreground of the fingerprint from the image under consideration. The algorithm uses three features, mean, variance and coherence. Based on these features, a rule system is built to help the algorithm to efficiently segment the image. In addition, the proposed algorithm combine split and merge with modified Otsu. Both enhancements techniques such as Gaussian filter and histogram equalization are applied to enhance and improve th...

  4. Fuse Modeling for Reliability Study of Power Electronics Circuits

    DEFF Research Database (Denmark)

    Bahman, Amir Sajjad; Iannuzzo, Francesco; Blaabjerg, Frede

    2017-01-01

    This paper describes a comprehensive modeling approach on reliability of fuses used in power electronic circuits. When fuses are subjected to current pulses, cyclic temperature stress is introduced to the fuse element and will wear out the component. Furthermore, the fuse may be used in a large...

  5. Fuse Modeling for Reliability Study of Power Electronics Circuits

    DEFF Research Database (Denmark)

    Bahman, Amir Sajjad; Iannuzzo, Francesco; Blaabjerg, Frede

    2017-01-01

    This paper describes a comprehensive modeling approach on reliability of fuses used in power electronic circuits. When fuses are subjected to current pulses, cyclic temperature stress is introduced to the fuse element and will wear out the component. Furthermore, the fuse may be used in a large...

  6. Wafer-fused semiconductor radiation detector

    Science.gov (United States)

    Lee, Edwin Y.; James, Ralph B.

    2002-01-01

    Wafer-fused semiconductor radiation detector useful for gamma-ray and x-ray spectrometers and imaging systems. The detector is fabricated using wafer fusion to insert an electrically conductive grid, typically comprising a metal, between two solid semiconductor pieces, one having a cathode (negative electrode) and the other having an anode (positive electrode). The wafer fused semiconductor radiation detector functions like the commonly used Frisch grid radiation detector, in which an electrically conductive grid is inserted in high vacuum between the cathode and the anode. The wafer-fused semiconductor radiation detector can be fabricated using the same or two different semiconductor materials of different sizes and of the same or different thicknesses; and it may utilize a wide range of metals, or other electrically conducting materials, to form the grid, to optimize the detector performance, without being constrained by structural dissimilarity of the individual parts. The wafer-fused detector is basically formed, for example, by etching spaced grooves across one end of one of two pieces of semiconductor materials, partially filling the grooves with a selected electrical conductor which forms a grid electrode, and then fusing the grooved end of the one semiconductor piece to an end of the other semiconductor piece with a cathode and an anode being formed on opposite ends of the semiconductor pieces.

  7. OPUS: the FUSE science data pipeline

    Science.gov (United States)

    Rose, James F.; Heller-Boyer, C.; Rose, M. A.; Swam, M.; Miller, W.; Kriss, G. A.; Oegerle, William R.

    1998-07-01

    This paper describes how the OPUS pipeline, currently used for processing science data from the Hubble Space Telescope (HST), was used as the backbone for developing the science data pipeline for a much smaller mission. The far ultraviolet spectroscopic explorer (FUSE) project selected OPUS for its data processing pipeline platform and selected the OPUS team at the STScI to write the FUSE pipeline applications. A total of 105 new modules were developed for the FUSE pipeline. The foundation of over 250 modules in the OPUS libraries allowed development to proceed quickly and with considerable confidence that the underlying functionality is reliable and robust. Each task represented roughly 90 percent reuse, and the project as a whole shows over 70 percent reuse of the existing OPUS system. Taking an existing system that is operational, and will be maintained for many years to come, was a key decision for the FUSE mission. Adding the extensive experience of the OPUS team to the task resulted in the development of a complete telemetry pipeline system within a matter of months. Reusable software has been the siren song of software engineering and object- oriented design for a decade or more. The development of inexpensive software systems by adapting existing code to new applications is as attractive as it has been elusive. The OPUS telemetry pipeline for the FUSE mission has proven to be a significant exception to that trend.

  8. Pelvic incidence-lumbar lordosis mismatch predisposes to adjacent segment disease after lumbar spinal fusion

    National Research Council Canada - National Science Library

    Rothenfluh, Dominique A; Mueller, Daniel A; Rothenfluh, Esin; Min, Kan

    ..., and numbers of segments fused with a mean follow-up of 84 months (61–142) (total n = 84). Several radiographic parameters were measured on pre- and postoperative radiographs, including lumbar lordosis measured (LL...

  9. Cluster Ensemble-based Image Segmentation

    Directory of Open Access Journals (Sweden)

    Xiaoru Wang

    2013-07-01

    Full Text Available Image segmentation is the foundation of computer vision applications. In this paper, we propose a new\tcluster ensemble-based image\tsegmentation algorithm, which overcomes several problems of traditional methods. We make two main contributions in this paper. First, we introduce the cluster ensemble concept to fuse the segmentation results from different types of visual features effectively, which can deliver a better final result and achieve a much more stable performance for broad categories of images. Second, we exploit the PageRank idea from Internet applications and apply it to the image segmentation task. This can improve the final segmentation results by combining the spatial information of the image and the semantic similarity of regions. Our experiments on four public image databases validate the superiority of our algorithm over conventional single type of feature or multiple types of features-based algorithms, since our algorithm can fuse multiple types of features effectively for better segmentation results. Moreover, our method is also proved to be very competitive in comparison with other state-of-the-art segmentation algorithms.

  10. Endodontic and post-endodontic management of a fused molar

    Directory of Open Access Journals (Sweden)

    Ruchi Gupta

    2013-01-01

    Full Text Available Treatment of fused teeth needs special care and attention to the bizarre anatomy. This paper describes root canal treatment of a fused carious tooth presenting with apical periodontitis. It is a rare case of fusion of the mandibular second molar with a paramolar. There is no literature regarding placement of crown over endodontically treated fused teeth. In this case, the fused teeth were endodontically treated and restored by a porcelain fused to metal crown.

  11. Fused silica windows for solar receiver applications

    Science.gov (United States)

    Hertel, Johannes; Uhlig, Ralf; Söhn, Matthias; Schenk, Christian; Helsch, Gundula; Bornhöft, Hansjörg

    2016-05-01

    A comprehensive study of optical and mechanical properties of quartz glass (fused silica) with regard to application in high temperature solar receivers is presented. The dependence of rupture strength on different surface conditions as well as high temperature is analyzed, focussing particularly on damage by devitrification and sandblasting. The influence of typical types of contamination in combination with thermal cycling on the optical properties of fused silica is determined. Cleaning methods are compared regarding effectiveness on contamination-induced degradation for samples with and without antireflective coating. The FEM-aided design of different types of receiver windows and their support structure is presented. A large-scale production process has been developed for producing fused silica dome shaped windows (pressurized window) up to a diameter of 816 mm. Prototypes were successfully pressure-tested in a test bench and certified according to the European Pressure Vessel Directive.

  12. Fusing Facial Features for Face Recognition

    Directory of Open Access Journals (Sweden)

    Jamal Ahmad Dargham

    2012-06-01

    Full Text Available Face recognition is an important biometric method because of its potential applications in many fields, such as access control, surveillance, and human-computer interaction. In this paper, a face recognition system that fuses the outputs of three face recognition systems based on Gabor jets is presented. The first system uses the magnitude, the second uses the phase, and the third uses the phase-weighted magnitude of the jets. The jets are generated from facial landmarks selected using three selection methods. It was found out that fusing the facial features gives better recognition rate than either facial feature used individually regardless of the landmark selection method.

  13. Fungal Systematics and Evolution: FUSE 1

    NARCIS (Netherlands)

    Crous, Pedro W; Schumacher, René K; Wingfield, Michael J; Lombard, Lorenzo; Giraldo, Alejandra; Christensen, Martha; Gardiennet, Alain; Nakashima, Chiharu; Pereira, Olinto L; Smith, Alexander J; Groenewald, Johannes Z

    2015-01-01

    Fungal Systematics and Evolution (FUSE) is introduced as a new series to expedite the publication of issues relating to the epitypification of formerly described species, report new sexual-asexual connections, the merging of sexual and asexual gen¬era following the end of dual nomenclature, and to

  14. Fused aromatic thienopyrazines: structure, properties and function

    KAUST Repository

    Mondal, Rajib

    2010-01-01

    Recent development of a fused aromatic thieno[3.4-b]pyrazine system and their application in optoelectronic devices are reviewed. Introduction of a fused aromatic unit followed by side chain engineering, dramatically enhanced the charge carrier mobility in thin film transistor devices and mobilities up to 0.2 cm2/Vs were achieved. The optoelectronic properties of these fused aromatic thienopyrazine polymers (Eg = 1.3 to 1.6 eV, HOMO = -4.9 to -5.2 V) were tuned by introduction of various fused aromatic rings within thienopyrazine. By balancing the fundamental properties of these polymers, both high charge carrier mobilities and moderate PCEs in solar cells were achieved. Further, effects of copolymerizing units are discussed. Low band gap semiconducting polymer (Eg ∼ 1 eV) with high field effect mobility (0.044 cm2/Vs) was obtained using cyclopentadithiophene as copolymerizing unit. Finally, a molecular design approach to enhance the absorption coefficients is discussed, which resulted in improved power conversion efficiency in bulk heterojunction solar cells. © 2010 The Royal Society of Chemistry.

  15. Renovating a Fusee Ceramique Barrel Vault

    NARCIS (Netherlands)

    Kamerling, M.W.

    2015-01-01

    This paper describes a proposal to renovate a Fusee Ceramique Barrel Vault with steel diagonals In 1956 two workshops, varying in height and span, were built in Wormerveer, The Netherlands. Both workshops were roofed with a concrete barrel vault with a thickness of 110 mm. The cylindrical vaults w

  16. 30 CFR 56.6502 - Safety fuse.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Safety fuse. 56.6502 Section 56.6502 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... initiation systems, igniter cord and connectors, or other nonelectric initiation systems shall be used...

  17. Demonstrating Earth Connections and Fuses Working Together

    Science.gov (United States)

    Harrison, Mark

    2017-01-01

    Earth wires and fuses work together in UK mains circuits to keep users safe from electric shocks and are taught in many school contexts. The subject can be quite abstract and difficult for pupils to grasp, and a simple but visually clear and direct demonstration is described which would be easy for most physics departments to build and which can…

  18. Deep Dynamic Neural Networks for Multimodal Gesture Segmentation and Recognition.

    Science.gov (United States)

    Wu, Di; Pigou, Lionel; Kindermans, Pieter-Jan; Le, Nam Do-Hoang; Shao, Ling; Dambre, Joni; Odobez, Jean-Marc

    2016-08-01

    This paper describes a novel method called Deep Dynamic Neural Networks (DDNN) for multimodal gesture recognition. A semi-supervised hierarchical dynamic framework based on a Hidden Markov Model (HMM) is proposed for simultaneous gesture segmentation and recognition where skeleton joint information, depth and RGB images, are the multimodal input observations. Unlike most traditional approaches that rely on the construction of complex handcrafted features, our approach learns high-level spatio-temporal representations using deep neural networks suited to the input modality: a Gaussian-Bernouilli Deep Belief Network (DBN) to handle skeletal dynamics, and a 3D Convolutional Neural Network (3DCNN) to manage and fuse batches of depth and RGB images. This is achieved through the modeling and learning of the emission probabilities of the HMM required to infer the gesture sequence. This purely data driven approach achieves a Jaccard index score of 0.81 in the ChaLearn LAP gesture spotting challenge. The performance is on par with a variety of state-of-the-art hand-tuned feature-based approaches and other learning-based methods, therefore opening the door to the use of deep learning techniques in order to further explore multimodal time series data.

  19. [Segmental neurofibromatosis].

    Science.gov (United States)

    Zulaica, A; Peteiro, C; Pereiro, M; Pereiro Ferreiros, M; Quintas, C; Toribio, J

    1989-01-01

    Four cases of segmental neurofibromatosis (SNF) are reported. It is a rare entity considered to be a localized variant of neurofibromatosis (NF)-Riccardi's type V. Two cases are male and two female. The lesions are located to the head in a patient and the other three cases in the trunk. No family history nor transmission to progeny were manifested. The rest of the organs are undamaged.

  20. Textiles: Some technocal information and data VI: fusing

    CSIR Research Space (South Africa)

    Cawood, MP

    1980-09-01

    Full Text Available results. However, complaints of problem do occur particularly with the technology becoming more sophisticated. Fusing interlinings are coated with an adhesive which enables them to be fused under certain conditions of temperature, time and pressure onto...

  1. Using conceptual spaces to fuse knowledge from heterogeneous robot platforms

    Science.gov (United States)

    Kira, Zsolt

    2010-04-01

    As robots become more common, it becomes increasingly useful for many applications to use them in teams that sense the world in a distributed manner. In such situations, the robots or a central control center must communicate and fuse information received from multiple sources. A key challenge for this problem is perceptual heterogeneity, where the sensors, perceptual representations, and training instances used by the robots differ dramatically. In this paper, we use Gärdenfors' conceptual spaces, a geometric representation with strong roots in cognitive science and psychology, in order to represent the appearance of objects and show how the problem of heterogeneity can be intuitively explored by looking at the situation where multiple robots differ in their conceptual spaces at different levels. To bridge low-level sensory differences, we abstract raw sensory data into properties (such as color or texture categories), represented as Gaussian Mixture Models, and demonstrate that this facilitates both individual learning and the fusion of concepts between robots. Concepts (e.g. objects) are represented as a fuzzy mixture of these properties. We then treat the problem where the conceptual spaces of two robots differ and they only share a subset of these properties. In this case, we use joint interaction and statistical metrics to determine which properties are shared. Finally, we show how conceptual spaces can handle the combination of such missing properties when fusing concepts received from different robots. We demonstrate the fusion of information in real-robot experiments with a Mobile Robots Amigobot and Pioneer 2DX with significantly different cameras and (on one robot) a SICK lidar.ÿÿÿÿ

  2. Multimodal Plasmonics in Fused Colloidal Networks

    CERN Document Server

    Teulle, Alexandre; Girard, C; Gurunatha, Kargal L; Li, Mei; Mann, Stephen; Dujardin, Erik

    2014-01-01

    Harnessing the optical properties of noble metals down to the nanometer-scale is a key step towards fast and low-dissipative information processing. At the 10-nm length scale, metal crystallinity and patterning as well as probing of surface plasmon (SP) properties must be controlled with a challenging high level of precision. Here, we demonstrate that ultimate lateral confinement and delocalization of SP modes are simultaneously achieved in extended self-assembled networks comprising linear chains of partially fused gold nanoparticles. The spectral and spatial distributions of the SP modes associated with the colloidal superstructures are evidenced by performing monochromated electron energy loss spectroscopy with a nanometer-sized electron probe. We prepare the metallic bead strings by electron beam-induced interparticle fusion of nanoparticle networks. The fused superstructures retain the native morphology and crystallinity but develop very low energy SP modes that are capable of supporting long range and s...

  3. Pressure evolution during HBC fuse operation

    Energy Technology Data Exchange (ETDEWEB)

    Rochette, D; Bussiere, W [Laboratoire Arc Electrique et Plasmas Thermiques (LAEPT)-CNRS UMR 6069, Universite Blaise Pascal, 24 Avenue des Landais, F 63177 Aubiere Cedex (France)

    2004-05-01

    The purpose of this paper is to describe the influence of the silica sand grains on pressure during the energy release in a high breaking capacity (HBC) fuse. During the HBC fuse operation, the pressure evolution is the result of two opposite trends: the pressure increase due to the interaction of the silica plasma with the surrounding granular sand, and the pressure decrease due to the propagation of the pressure waves toward the porous medium. Due to the complex phenomena occurring during the current extinction by a fuse, two kinds of pressure are distinguished: the pressure inside the silica plasma and the pressure in the silica sand. From the simulations we show that the Forchheimer flow resistance is stronger than the Darcy flow resistance once the electric power is over 30% of the maximum value. A comparison of the calculated and measured pressures is made at various positions from the fuse element axis. Two different pressures are obtained experimentally: the pressure P{sub SAND} exerted on the sand grains due to the plasma pressure, and the pressure P{sub GAS} of the gas flowing through the interstices of the silica sand. We show that the experimental and calculated trends are similar and they both depend on the electric power level and the silica sand mean granulometry. The maximum pressures are observed at the same time as the maximum electric power levels. The ratio P{sub SAND}/P{sub GAS} is about 8 with P{sub GAS} values not exceeding 1.5 x 10{sup 5} Pa.

  4. Demonstrating Earth connections and fuses working together

    Science.gov (United States)

    Harrison, Mark

    2017-03-01

    Earth wires and fuses work together in UK mains circuits to keep users safe from electric shocks and are taught in many school contexts. The subject can be quite abstract and difficult for pupils to grasp, and a simple but visually clear and direct demonstration is described which would be easy for most physics departments to build and which can make the concepts much more immediately understandable.

  5. Mixed segmentation

    DEFF Research Database (Denmark)

    Bonde, Anders; Aagaard, Morten; Hansen, Allan Grutt

    This book is about using recent developments in the fields of data analytics and data visualization to frame new ways of identifying target groups in media communication. Based on a mixed-methods approach, the authors combine psychophysiological monitoring (galvanic skin response) with textual...... content analysis and audience segmentation in a single-source perspective. The aim is to explain and understand target groups in relation to, on the one hand, emotional response to commercials or other forms of audio-visual communication and, on the other hand, living preferences and personality traits...

  6. Modelling and Analysis of Proximity Effect in IGBT Fuses

    DEFF Research Database (Denmark)

    Iov, Florin; Blaabjerg, Frede; Rasmussen, Henrik

    2005-01-01

    . Even with an active protection, a high power IGBT still has a risk of exhibiting a violent rupture in the case of a fault if e.g. IGBT fuses are not protecting it. By introducing fuses into voltage source converters a better protection of IGBT's can be achieved. However, skin and proximity effects...... affect the current distribution in a fuse due to the high frequency currents and thus a need for de-rating the fuse. This paper shows an analytical model for studying the proximity effect into a fuse. The results obtained using this model are compared with experiments....

  7. A Kalman Filtering Perspective for Multiatlas Segmentation.

    Science.gov (United States)

    Gao, Yi; Zhu, Liangjia; Cates, Joshua; MacLeod, Rob S; Bouix, Sylvain; Tannenbaum, Allen

    In multiatlas segmentation, one typically registers several atlases to the novel image, and their respective segmented label images are transformed and fused to form the final segmentation. In this work, we provide a new dynamical system perspective for multiatlas segmentation, inspired by the following fact: The transformation that aligns the current atlas to the novel image can be not only computed by direct registration but also inferred from the transformation that aligns the previous atlas to the image together with the transformation between the two atlases. This process is similar to the global positioning system on a vehicle, which gets position by inquiring from the satellite and by employing the previous location and velocity-neither answer in isolation being perfect. To solve this problem, a dynamical system scheme is crucial to combine the two pieces of information; for example, a Kalman filtering scheme is used. Accordingly, in this work, a Kalman multiatlas segmentation is proposed to stabilize the global/affine registration step. The contributions of this work are twofold. First, it provides a new dynamical systematic perspective for standard independent multiatlas registrations, and it is solved by Kalman filtering. Second, with very little extra computation, it can be combined with most existing multiatlas segmentation schemes for better registration/segmentation accuracy.

  8. Segmented blockcopolymers with uniform amide segments

    NARCIS (Netherlands)

    Husken, D.; Krijgsman, J.; Gaymans, R.J.

    2004-01-01

    Segmented blockcopolymers based on poly(tetramethylene oxide) (PTMO) soft segments and uniform crystallisable tetra-amide segments (TxTxT) are made via polycondensation. The PTMO soft segments, with a molecular weight of 1000 g/mol, are extended with terephthalic groups to a molecular weight of 6000

  9. 3D-SIFT-Flow for atlas-based CT liver image segmentation

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yan, E-mail: xuyan04@gmail.com [State Key Laboratory of Software Development Environment and Key Laboratory of Biomechanics and Mechanobiology of Ministry of Education, Beihang University, Beijing 100191, China and Research Institute of Beihang University in Shenzhen and Microsoft Research, Beijing 100080 (China); Xu, Chenchao, E-mail: chenchaoxu33@gmail.com; Kuang, Xiao, E-mail: kuangxiao.ace@gmail.com [School of Biological Science and Medical Engineering, Beihang University, Beijing 100191 (China); Wang, Hongkai, E-mail: wang.hongkai@gmail.com [Department of Biomedical Engineering, Dalian University of Technology, Dalian 116024 (China); Chang, Eric I-Chao, E-mail: eric.chang@microsoft.com [Microsoft Research, Beijing 100080 (China); Huang, Weimin, E-mail: wmhuang@i2r.a-star.edu.sg [Institute for Infocomm Research (I2R), Singapore 138632 (Singapore); Fan, Yubo, E-mail: yubofan@buaa.edu.cn [Key Laboratory of Biomechanics and Mechanobiology of Ministry of Education, Beihang University, Beijing 100191 (China)

    2016-05-15

    Purpose: In this paper, the authors proposed a new 3D registration algorithm, 3D-scale invariant feature transform (SIFT)-Flow, for multiatlas-based liver segmentation in computed tomography (CT) images. Methods: In the registration work, the authors developed a new registration method that takes advantage of dense correspondence using the informative and robust SIFT feature. The authors computed the dense SIFT features for the source image and the target image and designed an objective function to obtain the correspondence between these two images. Labeling of the source image was then mapped to the target image according to the former correspondence, resulting in accurate segmentation. In the fusion work, the 2D-based nonparametric label transfer method was extended to 3D for fusing the registered 3D atlases. Results: Compared with existing registration algorithms, 3D-SIFT-Flow has its particular advantage in matching anatomical structures (such as the liver) that observe large variation/deformation. The authors observed consistent improvement over widely adopted state-of-the-art registration methods such as ELASTIX, ANTS, and multiatlas fusion methods such as joint label fusion. Experimental results of liver segmentation on the MICCAI 2007 Grand Challenge are encouraging, e.g., Dice overlap ratio 96.27% ± 0.96% by our method compared with the previous state-of-the-art result of 94.90% ± 2.86%. Conclusions: Experimental results show that 3D-SIFT-Flow is robust for segmenting the liver from CT images, which has large tissue deformation and blurry boundary, and 3D label transfer is effective and efficient for improving the registration accuracy.

  10. 3D-SIFT-Flow for atlas-based CT liver image segmentation.

    Science.gov (United States)

    Xu, Yan; Xu, Chenchao; Kuang, Xiao; Wang, Hongkai; Chang, Eric I-Chao; Huang, Weimin; Fan, Yubo

    2016-05-01

    In this paper, the authors proposed a new 3D registration algorithm, 3D-scale invariant feature transform (SIFT)-Flow, for multiatlas-based liver segmentation in computed tomography (CT) images. In the registration work, the authors developed a new registration method that takes advantage of dense correspondence using the informative and robust SIFT feature. The authors computed the dense SIFT features for the source image and the target image and designed an objective function to obtain the correspondence between these two images. Labeling of the source image was then mapped to the target image according to the former correspondence, resulting in accurate segmentation. In the fusion work, the 2D-based nonparametric label transfer method was extended to 3D for fusing the registered 3D atlases. Compared with existing registration algorithms, 3D-SIFT-Flow has its particular advantage in matching anatomical structures (such as the liver) that observe large variation/deformation. The authors observed consistent improvement over widely adopted state-of-the-art registration methods such as ELASTIX, ANTS, and multiatlas fusion methods such as joint label fusion. Experimental results of liver segmentation on the MICCAI 2007 Grand Challenge are encouraging, e.g., Dice overlap ratio 96.27% ± 0.96% by our method compared with the previous state-of-the-art result of 94.90% ± 2.86%. Experimental results show that 3D-SIFT-Flow is robust for segmenting the liver from CT images, which has large tissue deformation and blurry boundary, and 3D label transfer is effective and efficient for improving the registration accuracy.

  11. Joint ventures

    DEFF Research Database (Denmark)

    Sørensen, Karsten Engsig

    Afhandlingen analysere de konkurrenceretlige og selskabsretlige regler som er bestemmende for hvordan et joint venture samarbejde er struktureret......Afhandlingen analysere de konkurrenceretlige og selskabsretlige regler som er bestemmende for hvordan et joint venture samarbejde er struktureret...

  12. Joint swelling

    Science.gov (United States)

    ... chap 275. Raftery AT, Lim E, Ostor AJK. Joint disorders. In: Raftery AT, Lim E, Ostor AJK, eds. ... A.M. Editorial team. Related MedlinePlus Health Topics Joint Disorders Browse the Encyclopedia A.D.A.M., Inc. ...

  13. A Latent Source Model for Patch-Based Image Segmentation.

    Science.gov (United States)

    Chen, George H; Shah, Devavrat; Golland, Polina

    2015-10-01

    Despite the popularity and empirical success of patch-based nearest-neighbor and weighted majority voting approaches to medical image segmentation, there has been no theoretical development on when, why, and how well these nonparametric methods work. We bridge this gap by providing a theoretical performance guarantee for nearest-neighbor and weighted majority voting segmentation under a new probabilistic model for patch-based image segmentation. Our analysis relies on a new local property for how similar nearby patches are, and fuses existing lines of work on modeling natural imagery patches and theory for nonparametric classification. We use the model to derive a new patch-based segmentation algorithm that iterates between inferring local label patches and merging these local segmentations to produce a globally consistent image segmentation. Many existing patch-based algorithms arise as special cases of the new algorithm.

  14. Morphological and molecular data argue for the labrum being non-apical, articulated, and the appendage of the intercalary segment in the locust.

    Science.gov (United States)

    Boyan, G S; Williams, J L D; Posser, S; Bräunig, P

    2002-09-01

    Our analysis of head segmentation in the locust embryo reveals that the labrum is not apical as often interpreted but constitutes the topologically fused appendicular pair of appendages of the third head metamere. Using molecular, immunocytochemical and retrograde axonal staining methods we show that this metamere, the intercalary segment, is innervated by the third brain neuromere-the tritocerebrum. Evidence for the appendicular nature of the labrum is firstly, the presence of an engrailed stripe within its posterior epithelium as is typical of all appendages in the early embryo. Secondly, the labrum is innervated by a segmental nerve originating from the third brain neuromere (the tritocerebrum). Immunocytochemical staining with Lazarillo and horseradish peroxidase antibodies reveal that sensory neurons on the labrum contribute to the segmental (tritocerebral) nerve via the labral nerve in the same way as for the appendages immediately anterior (antenna) and posterior (mandible) on the head. All but one of the adult and embryonic motoneurons innervating the muscles of the labrum have their cell bodies and dendrites located completely within the tritocerebral neuromere and putatively derive from engrailed expressing tritocerebral neuroblasts. Molecular evidence (repo) suggests the labrum is not only appendicular but also articulated, comprising two jointed elements homologous to the coxa and trochanter of the leg.

  15. Optical Performance Modeling of FUSE Telescope Mirror

    Science.gov (United States)

    Saha, Timo T.; Ohl, Raymond G.; Friedman, Scott D.; Moos, H. Warren

    2000-01-01

    We describe the Metrology Data Processor (METDAT), the Optical Surface Analysis Code (OSAC), and their application to the image evaluation of the Far Ultraviolet Spectroscopic Explorer (FUSE) mirrors. The FUSE instrument - designed and developed by the Johns Hopkins University and launched in June 1999 is an astrophysics satellite which provides high resolution spectra (lambda/Delta(lambda) = 20,000 - 25,000) in the wavelength region from 90.5 to 118.7 nm The FUSE instrument is comprised of four co-aligned, normal incidence, off-axis parabolic mirrors, four Rowland circle spectrograph channels with holographic gratings, and delay line microchannel plate detectors. The OSAC code provides a comprehensive analysis of optical system performance, including the effects of optical surface misalignments, low spatial frequency deformations described by discrete polynomial terms, mid- and high-spatial frequency deformations (surface roughness), and diffraction due to the finite size of the aperture. Both normal incidence (traditionally infrared, visible, and near ultraviolet mirror systems) and grazing incidence (x-ray mirror systems) systems can be analyzed. The code also properly accounts for reflectance losses on the mirror surfaces. Low frequency surface errors are described in OSAC by using Zernike polynomials for normal incidence mirrors and Legendre-Fourier polynomials for grazing incidence mirrors. The scatter analysis of the mirror is based on scalar scatter theory. The program accepts simple autocovariance (ACV) function models or power spectral density (PSD) models derived from mirror surface metrology data as input to the scatter calculation. The end product of the program is a user-defined pixel array containing the system Point Spread Function (PSF). The METDAT routine is used in conjunction with the OSAC program. This code reads in laboratory metrology data in a normalized format. The code then fits the data using Zernike polynomials for normal incidence

  16. Indirect slumping of D263 glass on Fused Silica mould

    Science.gov (United States)

    Proserpio, Laura; Wen, Mingwu; Breunig, Elias; Burwitz, Vadim; Friedrich, Peter; Madarasz, Emanuel

    2016-07-01

    The Slumped Glass Optic (SGO) group of the Max Planck Institute for Extraterrestrial physics (MPE) is studying the indirect slumping technology for its application to X-ray telescope manufacturing. Several aspects of the technology have been analyzed in the past. During the last months, we concentrated our activities on the slumping of Schott D263 glass on a precise machined Fused Silica mould: The concave mould was produced by the Italian company Media Lario Technologies with the parabola and hyperbola side of the typical Wolter I design in one single piece. Its shape quality was estimated by optical metrology to be around 6 arcsec Half Energy Width (HEW) in double reflection. The application of an anti-sticking Boron Nitride layer was necessary to avoid the adhesion of the glass on the mould during the forming process at high temperatures. The mould has been used for the slumping of seven mirror segments 200 mm long, 100 mm wide, and with thickness of 200 μm or 400 μm. The influence of the holding time at maximum temperature was explored in this first run of tests. The current results of the activities are described in the paper and plans for further investigations are outlined.

  17. Quartz/fused silica chip carriers

    Science.gov (United States)

    1992-01-01

    The primary objective of this research and development effort was to develop monolithic microwave integrated circuit (MMIC) packaging which will operate efficiently at millimeter-wave frequencies. The packages incorporated fused silica as the substrate material which was selected due to its favorable electrical properties and potential performance improvement over more conventional materials for Ka-band operation. The first step towards meeting this objective is to develop a package that meets standard mechanical and thermal requirements using fused silica and to be compatible with semiconductor devices operating up to at least 44 GHz. The second step is to modify the package design and add multilayer and multicavity capacity to allow for application specific integrated circuits (ASIC's) to control multiple phase shifters. The final step is to adapt the package design to a phased array module with integral radiating elements. The first task was a continuation of the SBIR Phase 1 work. Phase 1 identified fused silica as a viable substrate material by demonstrating various plating, machining, and adhesion properties. In Phase 2 Task 1, a package was designed and fabricated to validate these findings. Task 2 was to take the next step in packaging and fabricate a multilayer, multichip module (MCM). This package is the predecessor to the phased array module and demonstrates the ability to via fill, circuit print, laminate, and to form vertical interconnects. The final task was to build a phased array module. The radiating elements were to be incorporated into the package instead of connecting to it with wire or ribbon bonds.

  18. Self-assembling segmented coiled tubing

    Energy Technology Data Exchange (ETDEWEB)

    Raymond, David W.

    2016-09-27

    Self-assembling segmented coiled tubing is a concept that allows the strength of thick-wall rigid pipe, and the flexibility of thin-wall tubing, to be realized in a single design. The primary use is for a drillstring tubular, but it has potential for other applications requiring transmission of mechanical loads (forces and torques) through an initially coiled tubular. The concept uses a spring-loaded spherical `ball-and-socket` type joint to interconnect two or more short, rigid segments of pipe. Use of an optional snap ring allows the joint to be permanently made, in a `self-assembling` manner.

  19. Joint ventures

    NARCIS (Netherlands)

    M.N. Hoogendoorn (Martin)

    2009-01-01

    textabstractEen veel voorkomende wijze van samenwerking tussen ondernemingen is het uitvoeren van activiteiten in de vorm van een joint venture. Een joint venture is bijna altijd een afzonderlijke juridische entiteit. De partners in de joint venture voeren gezamenlijk de zeggenschap uit. In internat

  20. Joint ventures

    NARCIS (Netherlands)

    M.N. Hoogendoorn (Martin)

    2009-01-01

    textabstractEen veel voorkomende wijze van samenwerking tussen ondernemingen is het uitvoeren van activiteiten in de vorm van een joint venture. Een joint venture is bijna altijd een afzonderlijke juridische entiteit. De partners in de joint venture voeren gezamenlijk de zeggenschap uit. In internat

  1. A method to estimate relative orientations of body segments during movement using accelerometry

    NARCIS (Netherlands)

    Kortier, H.G.; Schenk, O.; Luinge, H.J.; Veltink, P.H.

    2011-01-01

    Quantitative assessment of human body movements includes the analysis of joint orientations. We propose a new method to estimate relative orientation between body segments using a single 3D accelerometer per segment.

  2. Medicinal Chemistry Perspective of Fused Isoxazole Derivatives.

    Science.gov (United States)

    Barmade, Mahesh A; Murumkar, Prashant R; Sharma, Mayank Kumar; Yadav, Mange Ram

    2016-01-01

    Nitrogen containing heterocyclic rings with an oxygen atom is considered as one of the best combination in medicinal chemistry due to their diversified biological activities. Isoxazole, a five membered heterocyclic azole ring is found in naturally occuring ibetonic acid along with some of the marketed drugs such as valdecoxib, flucloxacillin, cloxacillin, dicloxacillin, and danazol. It is also significant for showing antipsychotic activity in risperidone and anticonvulsant activity in zonisamide, the marketed drugs. This review article covers research articles reported till date covering biological activity along with SAR of fused isoxazole derivatives.

  3. Semiautomatic MDF deburring tool. [Mild detonating fuse

    Energy Technology Data Exchange (ETDEWEB)

    Simonton, W.L.

    1976-03-31

    A device for semiautomatically deburring the ends of lengths of MDF (mild detonating fuse) was developed by the Automation Development group at Mound Laboratory. The device performs the deburring function by cutting a 0.002 in. x 0.002 in. chamfer on the MDF with small rotating blades. This air-operated, semiautomatic device provides improvement over the manual method of removing burrs by reduction in time and operator strain. A time study is underway to determine the time saved which is expected to be about 75 percent.

  4. A Pansharpening Method Based on HCT and Joint Sparse Model

    Directory of Open Access Journals (Sweden)

    XU Ning

    2016-04-01

    Full Text Available A novel fusion method based on the hyperspherical color transformation (HCT and joint sparsity model is proposed for decreasing the spectral distortion of fused image further. In the method, an intensity component and angles of each band of the multispectral image is obtained by HCT firstly, and then the intensity component is fused with the panchromatic image through wavelet transform and joint sparsity model. In the joint sparsity model, the redundant and complement information of the different images can be efficiently extracted and employed to yield the high quality results. Finally, the fused multi spectral image is obtained by inverse transforms of wavelet and HCT on the new lower frequency image and the angle components, respectively. Experimental results on Pleiades-1 and WorldView-2 satellites indicate that the proposed method achieves remarkable results.

  5. Passive legged, multi-segmented, robotic vehicle.

    Energy Technology Data Exchange (ETDEWEB)

    Hayward, David R.

    2003-11-01

    The Passive-legged, Multi-segmented, Robotic Vehicle concept is a simple legged vehicle that is modular and scaleable, and can be sized to fit through confined areas that are slightly larger than the size of the vehicle. A specific goal of this project was to be able to fit through the opening in the fabric of a chain link fence. This terrain agile robotic platform will be composed of multiple segments that are each equipped with appendages (legs) that resemble oars extending from a boat. Motion is achieved by pushing with these legs that can also flex to fold next to the body when passing through a constricted area. Each segment is attached to another segment using an actuated joint. This joint represents the only actuation required for mobility. The major feature of this type of mobility is that the terrain agility advantage of legs can be attained without the complexity of the multiple-actuation normally required for the many joints of an active leg. The minimum number of segments is two, but some concepts require three or more segments. This report discusses several concepts for achieving this type of mobility, their design, and the results obtained for each.

  6. Electrostatic Discharge Properties of Fused Silica Coatings

    Science.gov (United States)

    Andersen, Allen; Sim, Charles; Dennison, J. R.

    2012-10-01

    The electric field value at which electrostatic discharge (ESD) occurs was studied for thin coatings of fused silica (highly disordered SiO2/SiOx) on conductive substrates, such as those encountered as optical coatings and in Si microfabrication. The electrostatic breakdown field was determined using an increasing voltage, while monitoring the leakage current. A simple parallel-plate capacitor geometry was used, under medium vacuum and at temperatures down to ˜150 K using a liquid N2 reservoir. The breakdown field, pre-breakdown arcing and I-V curves for fused silica samples are compared for ˜60 nm and ˜80 μm thick, room and low temperature, and untreated and irradiated samples. Unlike typical I-V results for polymeric insulators, the thin film silica samples did not exhibit pre-breakdown arcing, displayed transitional resistivity after initial breakdown, and in many cases showed evidence of a second discontinuity in the I-V curves. This diversity of observed discharge phenomena is discussed in terms of breakdown modes and defect generation on a microscopic scale.

  7. Retrospective analysis of multi-level cervical artificial disc replacement compared with nearby segments fused for multi-level disc hernations%人工椎间盘置换与颈前路融合治疗多节段颈椎病回顾性分析

    Institute of Scientific and Technical Information of China (English)

    王衡; 刘英杰; 常江; 张锴; 朱卉敏

    2015-01-01

    years,ROM was close to preoperative level in group A,and according to the last follow-up,there were significant increase to compare with postoperatively 3 days,but there was no significant difference in group B on every time point.Conclusions Artificial disc replacement compared with muti-segment fusion is a new way to treat multi-level disc herniations surgically,with good clinical results,and there were little effect on the range of motion.So artificial disc replacement is an effective way to deal with the contradiction of motion and immobilization.

  8. Contractual Incompleteness, Unemployment, and Labour Market Segmentation

    DEFF Research Database (Denmark)

    Altmann, Steffen; Falk, Armin; Grunewald, Andreas;

    2014-01-01

    This article provides evidence that involuntary unemployment, and the segmentation of labour markets into firms offering "good" and "bad" jobs, may both arise as a consequence of contractual incompleteness.We provide a simple model that illustrates how unemployment and market segmentation may...... jointly emerge as part of a market equilibrium in environments where work effort is not third-party verifiable. Using experimental labour markets that differ only in the verifiability of effort, we demonstrate empirically that contractual incompleteness can cause unemployment and segmentation. Our data...

  9. Contractual Incompleteness, Unemployment, and Labour Market Segmentation

    DEFF Research Database (Denmark)

    Altmann, Steffen; Falk, Armin; Grunewald, Andreas

    2014-01-01

    This article provides evidence that involuntary unemployment, and the segmentation of labour markets into firms offering "good" and "bad" jobs, may both arise as a consequence of contractual incompleteness.We provide a simple model that illustrates how unemployment and market segmentation may...... jointly emerge as part of a market equilibrium in environments where work effort is not third-party verifiable. Using experimental labour markets that differ only in the verifiability of effort, we demonstrate empirically that contractual incompleteness can cause unemployment and segmentation. Our data...

  10. Split Bregman method for large scale fused Lasso

    CERN Document Server

    Ye, Gui-Bo

    2010-01-01

    rdering of regression or classification coefficients occurs in many real-world applications. Fused Lasso exploits this ordering by explicitly regularizing the differences between neighboring coefficients through an $\\ell_1$ norm regularizer. However, due to nonseparability and nonsmoothness of the regularization term, solving the fused Lasso problem is computationally demanding. Existing solvers can only deal with problems of small or medium size, or a special case of the fused Lasso problem in which the predictor matrix is identity matrix. In this paper, we propose an iterative algorithm based on split Bregman method to solve a class of large-scale fused Lasso problems, including a generalized fused Lasso and a fused Lasso support vector classifier. We derive our algorithm using augmented Lagrangian method and prove its convergence properties. The performance of our method is tested on both artificial data and real-world applications including proteomic data from mass spectrometry and genomic data from array...

  11. Temporally consistent segmentation of point clouds

    Science.gov (United States)

    Owens, Jason L.; Osteen, Philip R.; Daniilidis, Kostas

    2014-06-01

    We consider the problem of generating temporally consistent point cloud segmentations from streaming RGB-D data, where every incoming frame extends existing labels to new points or contributes new labels while maintaining the labels for pre-existing segments. Our approach generates an over-segmentation based on voxel cloud connectivity, where a modified k-means algorithm selects supervoxel seeds and associates similar neighboring voxels to form segments. Given the data stream from a potentially mobile sensor, we solve for the camera transformation between consecutive frames using a joint optimization over point correspondences and image appearance. The aligned point cloud may then be integrated into a consistent model coordinate frame. Previously labeled points are used to mask incoming points from the new frame, while new and previous boundary points extend the existing segmentation. We evaluate the algorithm on newly-generated RGB-D datasets.

  12. Current advances in fused tetrathiafulvalene donor-acceptor systems.

    Science.gov (United States)

    Bergkamp, Jesse J; Decurtins, Silvio; Liu, Shi-Xia

    2015-02-21

    Electron donor (D) and acceptor (A) systems have been studied extensively. Among them, fused D-A systems have attracted much attention during the past decades. Herein, we will present the evolution of tetrathiafulvalene (TTF) fused D-A systems and their potential applications in areas such as solar cells, OFETs, molecular wires and optoelectronics just to name a few. The synthesis and electrochemical, photophysical and intrinsic properties of fused D-A systems will be described as well.

  13. The relative effectiveness of segment specific level and non-specific level spinal joint mobilization on pain and range of motion: results of a systematic review and meta-analysis.

    Science.gov (United States)

    Slaven, Emily Joan; Goode, Adam P; Coronado, Rogelio A; Poole, Charles; Hegedus, Eric J

    2013-02-01

    Systematic literature review and meta-analysis. IN SYMPTOMATIC SUBJECTS TO: (1) examine the effects of a single session of joint mobilization on pain at rest and with most painful movement, and (2) compare the effects when joint mobilization is provided to a specific or non-specific spinal level. Joint mobilization is routinely used for treating spinal pain in conjunction with other interventions, but its unique effect is not well understood. Further, there is controversy about the role of 'specific level' techniques in producing benefit. Searches were performed for randomized controlled trials (RCTs) using electronic databases (MEDLINE, CINAHL, and PEDro) from 1966 through November 2010. Methodological quality was assessed using previously detailed criteria. Meta-analysis and meta-regression were conducted on eligible studies. Eight RCTs with a mean methodological score of 10/12 were included. Significant heterogeneity (P = 0.075) was found in the overall meta-analysis estimate. When stratified by body location, no significant individual effect was found for pain at rest. However, there was a statistical mean difference [0.71 (95% confidence interval: 0.13-1.28)] between pain at rest for the cervical and lumbar individual means. We found multiple studies which provided evidence that a single session of joint mobilization can lead to a reduction of pain at rest and with most painful movement. When using joint mobilization, the need for specific versus non-specific level mobilization may be influenced by anatomical region; the direction of effect in the cervical spine was toward specific mobilization and in the lumbar spine towards non-specific mobilization.

  14. Real-time planar segmentation of depth images: from three-dimensional edges to segmented planes

    Science.gov (United States)

    Javan Hemmat, Hani; Bondarev, Egor; de With, Peter H. N.

    2015-09-01

    Real-time execution of processing algorithms for handling depth images in a three-dimensional (3-D) data framework is a major challenge. More specifically, considering depth images as point clouds and performing planar segmentation requires heavy computation, because available planar segmentation algorithms are mostly based on surface normals and/or curvatures, and, consequently, do not provide real-time performance. Aiming at the reconstruction of indoor environments, the spaces mainly consist of planar surfaces, so that a possible 3-D application would strongly benefit from a real-time algorithm. We introduce a real-time planar segmentation method for depth images avoiding any surface normal calculation. First, we detect 3-D edges in a depth image and generate line segments between the identified edges. Second, we fuse all the points on each pair of intersecting line segments into a plane candidate. Third and finally, we implement a validation phase to select planes from the candidates. Furthermore, various enhancements are applied to improve the segmentation quality. The GPU implementation of the proposed algorithm segments depth images into planes at the rate of 58 fps. Our pipeline-interleaving technique increases this rate up to 100 fps. With this throughput rate improvement, the application benefit of our algorithm may be further exploited in terms of quality and enhancing the localization.

  15. Understanding error generation in fused deposition modeling

    Science.gov (United States)

    Bochmann, Lennart; Bayley, Cindy; Helu, Moneer; Transchel, Robert; Wegener, Konrad; Dornfeld, David

    2015-03-01

    Additive manufacturing offers completely new possibilities for the manufacturing of parts. The advantages of flexibility and convenience of additive manufacturing have had a significant impact on many industries, and optimizing part quality is crucial for expanding its utilization. This research aims to determine the sources of imprecision in fused deposition modeling (FDM). Process errors in terms of surface quality, accuracy and precision are identified and quantified, and an error-budget approach is used to characterize errors of the machine tool. It was determined that accuracy and precision in the y direction (0.08-0.30 mm) are generally greater than in the x direction (0.12-0.62 mm) and the z direction (0.21-0.57 mm). Furthermore, accuracy and precision tend to decrease at increasing axis positions. The results of this work can be used to identify possible process improvements in the design and control of FDM technology.

  16. Laser Damage Precursors in Fused Silica

    Energy Technology Data Exchange (ETDEWEB)

    Miller, P; Suratwala, T; Bude, J; Laurence, T A; Shen, N; Steele, W A; Feit, M; Menapace, J; Wong, L

    2009-11-11

    There is a longstanding, and largely unexplained, correlation between the laser damage susceptibility of optical components and both the surface quality of the optics, and the presence of near surface fractures in an optic. In the present work, a combination of acid leaching, acid etching, and confocal time resolved photoluminescence (CTP) microscopy has been used to study laser damage initiation at indentation sites. The combination of localized polishing and variations in indentation loads allows one to isolate and characterize the laser damage susceptibility of densified, plastically flowed and fractured fused silica. The present results suggest that: (1) laser damage initiation and growth are strongly correlated with fracture surfaces, while densified and plastically flowed material is relatively benign, and (2) fracture events result in the formation of an electronically defective rich surface layer which promotes energy transfer from the optical beam to the glass matrix.

  17. Mid-IR fused fiber couplers

    Science.gov (United States)

    Stevens, G.; Woodbridge, T.

    2016-03-01

    We present results from our recent efforts on developing single-mode fused couplers in ZBLAN fibre. We have developed a custom fusion workstation for working with lower melting temperature fibres, such as ZBLAN and chalcogenide fibres. Our workstation uses a precisely controlled electrical heater designed to operate at temperatures between 100 - 250°C as our heat source. The heated region of the fibers was also placed in an inert atmosphere to avoid the formation of microcrystal inclusions during fusion. We firstly developed a process for pulling adiabatic tapers in 6/125 μm ZBLAN fibre. The tapers were measured actively during manufacture using a 2000 nm source. The process was automated so that the heater temperature and motor speed automatically adjusted to pull the taper at constant tension. This process was then further developed so that we could fuse and draw two parallel 6/125 μm ZBLAN fibres, forming a single-mode coupler. Low ratio couplers (1-10%) that could be used as power monitors were manufactured that had an excess loss of 0.76 dB. We have also manufactured 50/50 splitters and wavelength division multiplexers (WDMs). However, the excess loss of these devices was typically 2 - 3 dB. The increased losses were due to localised necking and surface defects forming as the tapers were pulled further to achieve a greater coupling ratio. Initial experiments with chalcogenide fibre have shown that our process can be readily adapted for chalcogenide fibres. A 5% coupler with 1.5 dB insertion loss was manufactured using commercial of the shelf (COTS) fibres.

  18. High Voltage Applications of Explosively Formed Fuses

    Science.gov (United States)

    Tasker, D. G.; Goforth, J. H.; Fowler, C. M.; Herrera, D. H.; King, J. C.; Lopez, E. A.; Martinez, E. C.; Oona, H.; Marsh, S. P.; Reinovsky, R. E.; Stokes, J.; Tabaka, L. J.; Torres, D. T.; Sena, F. C.; Kiuttu, G.; Degnan, J.

    2004-11-01

    At Los Alamos, we have primarily applied Explosively Formed Fuse (EFF) techniques to high current systems. In these systems, the EFF has interrupted currents from 19-25 MA, thus diverting the current to low inductance loads. The transferred current magnitude is determined by the ratio of storage inductance to load inductance and, with dynamic loads, the current has ranged from 12-20 MA. In a system with 18 MJ stored energy, the switch operates at a power of up to 6 TW. We are now investigating the use of the EFF technique to apply high voltages to high impedance loads in systems that are more compact. In these systems we are exploring circuits with EFF lengths from 43-100 cm, which have storage inductances large enough to apply 300-500 kV across high impedance loads. Experimental results and design considerations are presented. Using cylindrical EFF switches of 10 cm diameter and 43 cm length, currents of approximately 3 MA were interrupted producing ~200 kV. This indicates the switch had an effective resistance of ~100 mΩ where 150-200 mΩ was expected. To understand the lower performance, several parameters were studied including electrical conduction through the explosive products; current density; explosive initiation; insulator type and conductor thickness. The results show a number of interesting features, most notably that the primary mechanism of switch operation is mechanical and not electrical fusing of the conductor. Switches opening on a 1-10 μs time scale with resistances starting at 50 μΩ and increasing to perhaps 1 Ω now seem possible to construct using explosive charges as small as a few pounds.

  19. Strategic market segmentation

    National Research Council Canada - National Science Library

    Maričić Branko R; Đorđević Aleksandar

    2015-01-01

    ..., requires segmented approach to the market that appreciates differences in expectations and preferences of customers. One of significant activities in strategic planning of marketing activities is market segmentation...

  20. Ceramic joints

    Science.gov (United States)

    Miller, Bradley J.; Patten, Jr., Donald O.

    1991-01-01

    Butt joints between materials having different coefficients of thermal expansion are prepared having a reduced probability of failure of stress facture. This is accomplished by narrowing/tapering the material having the lower coefficient of thermal expansion in a direction away from the joint interface and not joining the narrow-tapered surface to the material having the higher coefficient of thermal expansion.

  1. Simultaneous Reconstruction and Segmentation with Class-Specific Priors

    DEFF Research Database (Denmark)

    Romanov, Mikhail

    for regularizing the reconstruction process. The thesis provides models and algorithms for simultaneous reconstruction and segmentation and their performance is empirically validated. Two method of simultaneous reconstruction and segmentation are described in the thesis. Also, a method for parameter selection......Studying the interior of objects using tomography often require an image segmentation, such that different material properties can be quantified. This can for example be volume or surface area. Segmentation is typically done as an image analysis step after the image has been reconstructed....... This thesis investigates computing the reconstruction and segmentation simultaneously. The advantage of this is that because the reconstruction and segmentation are computed jointly, reconstruction errors are not propagated to the segmentation step. Furthermore the segmentation procedure can be used...

  2. FUSE observations of the central star of Abell 78

    CERN Document Server

    Werner, K; Koesterke, L; Kruk, J W

    2002-01-01

    FUSE high resolution spectra of two PG1159 type central stars (K1-16 and NGC 7094) have revealed an unexpected iron deficiency of at least 1 or 2 dex (Miksa et al. 2002). Here we present early results of FUSE spectroscopy of the CSPN Abell 78. It is shown that iron is strongly deficient in this star, too.

  3. Fused Smart Sensor Network for Multi-Axis Forward Kinematics Estimation in Industrial Robots

    Directory of Open Access Journals (Sweden)

    Rene de Jesus Romero-Troncoso

    2011-04-01

    Full Text Available Flexible manipulator robots have a wide industrial application. Robot performance requires sensing its position and orientation adequately, known as forward kinematics. Commercially available, motion controllers use high-resolution optical encoders to sense the position of each joint which cannot detect some mechanical deformations that decrease the accuracy of the robot position and orientation. To overcome those problems, several sensor fusion methods have been proposed but at expenses of high-computational load, which avoids the online measurement of the joint’s angular position and the online forward kinematics estimation. The contribution of this work is to propose a fused smart sensor network to estimate the forward kinematics of an industrial robot. The developed smart processor uses Kalman filters to filter and to fuse the information of the sensor network. Two primary sensors are used: an optical encoder, and a 3-axis accelerometer. In order to obtain the position and orientation of each joint online a field-programmable gate array (FPGA is used in the hardware implementation taking advantage of the parallel computation capabilities and reconfigurability of this device. With the aim of evaluating the smart sensor network performance, three real-operation-oriented paths are executed and monitored in a 6-degree of freedom robot.

  4. SANTEN-fuse AS ANEARTHQUAKE DAMPER FOR PENDOPO JOGLO

    Directory of Open Access Journals (Sweden)

    MAER Bisatya W.

    2015-07-01

    Full Text Available The 2006 Yogyakarta earthquake resulted in collapse of several traditional buildings in Yogyakarta, including joglos. This fact indicates that joglos are quite vulnerable to low-frequency ground shaking. The stability and rigidity of a joglo building are provided by the core of the building, i.e. the rong-rongan structure, in which connection of sakaguru (the column-sunduk (the long span beam-kili (the short span beam has a rigid characteristic. This rigid rong-rongan structure behaves elastically during an earthquake event, and attracts large inertia force. This research aims to increase the structure performance of the rong-rongan by adding “SANTEN-fuse,” an earthquake vibration damper, and by changing the joint connection of sakaguru-sunduk-kili to be that of a pin connection, but not changing the physical appearance of rong-rongan. Santen, whose function is to transfer the load of the roof from blandar to sunduk and from pangeret to kili, is modified so that it has frictional damper characteristic. This “SANTEN-fuse” can resist shear force up to certain level before it slides and acting as a damper. With the reduced stiffness, which leads to reduced inertia force, the overall structural responses are expected to be lower. An experimental quantitative method was used by doing a simulation using SAP2000 software to verify the idea. The pendopo dalem Yudonegaran a joglo house in Yogyakarta was chosen as a case study. Non-linear time history analysis was conducted. Simulation results showed that the proposed modification of rong-rongan structure by using “SANTEN-fuse”, performed better than the original rong-rongan structure.

  5. Thermal performance of back-up current-limiting fuses

    Energy Technology Data Exchange (ETDEWEB)

    Torres, E.; Mazon, A.J.; Fernandez, E.; Zamora, I. [Department of Electrical Engineering, University of the Basque Country (UPV/EHU), Alameda de Urquijo, s/n, Bilbao 48013, Bizkaia (Spain); Perez, J.C. [MESA - Schneider Electric, Gatica 48110 (Spain)

    2010-12-15

    The design and development of current-limiting power fuses requires considerable time and expense on testing to verify that the maximum temperature limits under the rated current established in international standards are not exceeded. This paper presents a new methodology that reproduces the thermal behaviour of high voltage current-limiting fuses under currents up to the rated value and so, it reduces the need for testing as prototypes, more similar to the final design, can be obtained. Firstly, the methodology solves the transient heating process of the fuse to obtain the values of the power dissipated and the heat transfer coefficient, corresponding to the steady state condition. Once these values have been calculated, the temperature distribution at the surface of the complete fuse is obtained. The validity of the method proposed has been verified by comparison of the numerical values calculated with those obtained by testing real fuses. (author)

  6. Temporomandibular Joint, Closed

    Science.gov (United States)

    ... Gallery > Oral Health > The Temporomandibular Joint, Closed The Temporomandibular Joint, Closed Main Content Title: The Temporomandibular Joint, Closed Description: The temporomandibular joint connects the lower ...

  7. FISICO: Fast Image SegmentatIon COrrection.

    Directory of Open Access Journals (Sweden)

    Waldo Valenzuela

    Full Text Available In clinical diagnosis, medical image segmentation plays a key role in the analysis of pathological regions. Despite advances in automatic and semi-automatic segmentation techniques, time-effective correction tools are commonly needed to improve segmentation results. Therefore, these tools must provide faster corrections with a lower number of interactions, and a user-independent solution to reduce the time frame between image acquisition and diagnosis.We present a new interactive method for correcting image segmentations. Our method provides 3D shape corrections through 2D interactions. This approach enables an intuitive and natural corrections of 3D segmentation results. The developed method has been implemented into a software tool and has been evaluated for the task of lumbar muscle and knee joint segmentations from MR images.Experimental results show that full segmentation corrections could be performed within an average correction time of 5.5±3.3 minutes and an average of 56.5±33.1 user interactions, while maintaining the quality of the final segmentation result within an average Dice coefficient of 0.92±0.02 for both anatomies. In addition, for users with different levels of expertise, our method yields a correction time and number of interaction decrease from 38±19.2 minutes to 6.4±4.3 minutes, and 339±157.1 to 67.7±39.6 interactions, respectively.

  8. Impact of graft height on zygapophyseal joint pressure and range of motion adjacent to segment following cervical anterior fusion%颈椎前路融合术中植骨块的高度对邻近节段关节突压力及椎间位移的影响

    Institute of Scientific and Technical Information of China (English)

    罗春山; 欧阳北平; 梁栋柱; 陆廷盛; 姚书耽; 赵国权

    2016-01-01

    Objective To discuss impact of graft height on zygapophyseal joint pressure and range of motion of adjacent segments following the cervical anterior fusion and to guide the choice of optimal graft height in clinic. Methods Eight fresh-frozen human cadaveric cervical spines were used in this series, specimens were tested in five conditions, normal(specimens with intact discs)and different graft height(120%, 140%,160%of mean height) after Smith-Robinson discectomy between the fifth and sixth cervical vertebrae. Each specimens were subjected to flexion-extension. Lateral bending and axial rotation in material test system (BOSE ELECTROFORCE) were adopted to measure zygapophyseal joint pressure and rotation of the fourth to fifth segments and the sixth to seventh segments. Finally, The data for each state was used to determine the statistical significance of differences. Results The height of bone graft had little effect on the zygapophysial joints pressure values in neutral position with no statistical significance noted among each groups(P>0.05); The zygapophysial joints pressure value was the highest increase in extension position,but 120%M increased minimum of zygapophysial joints pressure value, and statistical significance were noted among each groups(P0.05), and statistical significance were noted in others groups(P0.05). Conclusion The appropriate graft height after single discectomy may be 120%mean height.%目的:探讨颈椎前路融合术中植骨块的高度对邻近节段关节突压力及活动度的影响,为临床上选择适宜的植骨高度提供依据。方法采用8例新鲜成人尸体颈椎标本,对完整状态,C5/6节段椎间隙减压术后(100%M、120%M、140%M、160%M)5组,于BOSE机加载下行三维运动,并测量颈C4/5,C6/7关节突压力值及C4/5,C6/7三维运动范围;最后将结果行多重比较分析。结果中立位状态下,关节突压力值各组无显著差异,P>0.05;后伸状态下,关节突压力

  9. Wavelet domain hidden markovian bayesian document segmentation

    Institute of Scientific and Technical Information of China (English)

    Sun Junxi; Xiao Changyan; Zhang Su; Chen Yazhu

    2005-01-01

    A novel algorithm for Bayesian document segmentation is proposed based on the wavelet domain hidden Markov tree (HMT) model. Once the parameters of model are known, according to the sequential maximum a posterior probability (SMAP) rule, firstly, the likelihood probability of HMT model for each pattern is computed from fine to coarse procedure. Then, the interscale state transition probability is solved using Expectation Maximum (EM) algorithm based on hybrid-quadtree and multiscale context information is fused from coarse to fine procedure. In order to get pixellevel segmentation, the redundant wavelet domain Gaussian mixture model (GMM) is employed to formulate pixel-level statistical property. The experiment results show that the proposed scheme is feasible and robust.

  10. Segmentation Similarity and Agreement

    CERN Document Server

    Fournier, Chris

    2012-01-01

    We propose a new segmentation evaluation metric, called segmentation similarity (S), that quantifies the similarity between two segmentations as the proportion of boundaries that are not transformed when comparing them using edit distance, essentially using edit distance as a penalty function and scaling penalties by segmentation size. We propose several adapted inter-annotator agreement coefficients which use S that are suitable for segmentation. We show that S is configurable enough to suit a wide variety of segmentation evaluations, and is an improvement upon the state of the art. We also propose using inter-annotator agreement coefficients to evaluate automatic segmenters in terms of human performance.

  11. Fused silica challenges in sensitive space applications

    Science.gov (United States)

    Criddle, Josephine; Nürnberg, Frank; Sawyer, Robert; Bauer, Peter; Langner, Andreas; Schötz, Gerhard

    2016-07-01

    Space bound as well as earthbound spectroscopy of extra-terrestrial objects finds its challenge in light sources with low intensities. High transmission for every optical element along the light path requires optical materials with outstanding performance to enable the measurement of even a one-photon event. Using the Lunar Laser Ranging Project and the LIGO and VIRGO Gravitational Wave Detectors as examples, the influence of the optical properties of fused silica will be described. The Visible and Infrared Surveillance Telescope for Astronomy (VISTA) points out the material behavior in the NIR regime, where the chemical composition of optical materials changes the performance. Special fibers are often used in combination with optical elements as light guides to the spectroscopic application. In an extended spectral range between 350 and 2,200 nm Heraeus developed STU fiber preforms dedicated for broad band spectroscopy in astronomy. STU fibers in the broad spectral range as well as SSU fibers for UV transmission (180 - 400 nm) show also high gamma radiation resistance which allows space applications.

  12. Joint pain

    Science.gov (United States)

    ... or conditions. It may be linked to arthritis , bursitis , and muscle pain . No matter what causes it, ... Autoimmune diseases such as rheumatoid arthritis and lupus Bursitis Chondromalacia patellae Crystals in the joint: Gout (especially ...

  13. Pituitary Adenoma Segmentation

    CERN Document Server

    Egger, Jan; Kuhnt, Daniela; Freisleben, Bernd; Nimsky, Christopher

    2011-01-01

    Sellar tumors are approximately 10-15% among all intracranial neoplasms. The most common sellar lesion is the pituitary adenoma. Manual segmentation is a time-consuming process that can be shortened by using adequate algorithms. In this contribution, we present a segmentation method for pituitary adenoma. The method is based on an algorithm we developed recently in previous work where the novel segmentation scheme was successfully used for segmentation of glioblastoma multiforme and provided an average Dice Similarity Coefficient (DSC) of 77%. This scheme is used for automatic adenoma segmentation. In our experimental evaluation, neurosurgeons with strong experiences in the treatment of pituitary adenoma performed manual slice-by-slice segmentation of 10 magnetic resonance imaging (MRI) cases. Afterwards, the segmentations were compared with the segmentation results of the proposed method via the DSC. The average DSC for all data sets was 77.49% +/- 4.52%. Compared with a manual segmentation that took, on the...

  14. Joint dynamics and intra-subject variability during countermovement jumps in children and adults

    DEFF Research Database (Denmark)

    Raffalt, Peter C; Alkjær, Tine; Simonsen, Erik B

    2016-01-01

    work, hip joint moment and hip and knee joint power. Higher intra-subject variation was observed in horizontal joint reaction force components for the children and higher intra-subject variation in the segment angular inertia components was observed for the adults. The joint dynamics of children during...

  15. SU-E-J-129: Atlas Development for Cardiac Automatic Contouring Using Multi-Atlas Segmentation

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, R; Yang, J; Pan, T; Milgrom, S; Pinnix, C; Shi, A; Yang, J; Liu, Y; Nguyen, Q; Gomez, D; Dabaja, B; Balter, P; Court, L; Liao, Z [MD Anderson Cancer Center, Houston, TX (United States)

    2015-06-15

    Purpose: To develop a set of atlases for automatic contouring of cardiac structures to determine heart radiation dose and the associated toxicity. Methods: Six thoracic cancer patients with both contrast and non-contrast CT images were acquired for this study. Eight radiation oncologists manually and independently delineated cardiac contours on the non-contrast CT by referring to the fused contrast CT and following the RTOG 1106 atlas contouring guideline. Fifteen regions of interest (ROIs) were delineated, including heart, four chambers, four coronary arteries, pulmonary artery and vein, inferior and superior vena cava, and ascending and descending aorta. Individual expert contours were fused using the simultaneous truth and performance level estimation (STAPLE) algorithm for each ROI and each patient. The fused contours became atlases for an in-house multi-atlas segmentation. Using leave-one-out test, we generated auto-segmented contours for each ROI and each patient. The auto-segmented contours were compared with the fused contours using the Dice similarity coefficient (DSC) and the mean surface distance (MSD). Results: Inter-observer variability was not obvious for heart, chambers, and aorta but was large for other structures that were not clearly distinguishable on CT image. The average DSC between individual expert contours and the fused contours were less than 50% for coronary arteries and pulmonary vein, and the average MSD were greater than 4.0 mm. The largest MSD of expert contours deviating from the fused contours was 2.5 cm. The mean DSC and MSD of auto-segmented contours were within one standard deviation of expert contouring variability except the right coronary artery. The coronary arteries, vena cava, and pulmonary vein had DSC<70% and MSD>3.0 mm. Conclusion: A set of cardiac atlases was created for cardiac automatic contouring, the accuracy of which was comparable to the variability in expert contouring. However, substantial modification may need

  16. Semantic Image Segmentation with Contextual Hierarchical Models.

    Science.gov (United States)

    Seyedhosseini, Mojtaba; Tasdizen, Tolga

    2016-05-01

    Semantic segmentation is the problem of assigning an object label to each pixel. It unifies the image segmentation and object recognition problems. The importance of using contextual information in semantic segmentation frameworks has been widely realized in the field. We propose a contextual framework, called contextual hierarchical model (CHM), which learns contextual information in a hierarchical framework for semantic segmentation. At each level of the hierarchy, a classifier is trained based on downsampled input images and outputs of previous levels. Our model then incorporates the resulting multi-resolution contextual information into a classifier to segment the input image at original resolution. This training strategy allows for optimization of a joint posterior probability at multiple resolutions through the hierarchy. Contextual hierarchical model is purely based on the input image patches and does not make use of any fragments or shape examples. Hence, it is applicable to a variety of problems such as object segmentation and edge detection. We demonstrate that CHM performs at par with state-of-the-art on Stanford background and Weizmann horse datasets. It also outperforms state-of-the-art edge detection methods on NYU depth dataset and achieves state-of-the-art on Berkeley segmentation dataset (BSDS 500).

  17. Technical report on galvanic cells with fused-salt electrolytes

    Science.gov (United States)

    Cairns, E. J.; Crouthamel, C. E.; Fischer, A. K.; Foster, M. S.; Hesson, J. C.; Johnson, C. E.; Shimotake, H.; Tevebaugh, A. D.

    1969-01-01

    Technical report is presented on sodium and lithium cells using fused salt electrolytes. It includes a discussion of the thermally regenerative galvanic cell and the secondary bimetallic cell for storage of electricity.

  18. Fused Cast Alumina Refractory Products for Glass Tank Furnace

    Institute of Scientific and Technical Information of China (English)

    SHEN Keyin

    2006-01-01

    @@ 1 Subject and Scope The standard specifies the requirement, testing method, inspection rule and requirements for the labeling, packing, shipping and storing of the fused cast alumina refractory products for glass tanks.

  19. Quantification of residual stress from photonic signatures of fused silica

    Science.gov (United States)

    Cramer, K. Elliott; Hayward, Maurice; Yost, William T.

    2014-02-01

    A commercially available grey-field polariscope (GFP) instrument for photoelastic examination is used to assess impact damage inflicted upon the outer-most pane of Space Shuttle windows made from fused silica. A method and apparatus for calibration of the stress-optic coefficient using four-point bending is discussed. The results are validated on known material (acrylic) and are found to agree with literature values to within 6%. The calibration procedure is then applied to fused-silica specimens and the stress-optic coefficient is determined to be 2.43 ± 0.54 × 10-12 Pa-1. Fused silica specimens containing impacts artificially made at NASA's Hypervelocity Impact Technology Facility (HIT-F), to simulate damage typical during space flight, are examined. The damage sites are cored from fused silica window carcasses and examined with the GFP. The calibrated GFP measurements of residual stress patterns surrounding the damage sites are presented.

  20. Polymer Matrix Composites using Fused Deposition Modeling Technology Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Fused deposition modeling (FDM) is an additive manufacturing technology that allows fabrication of complex three-dimensional geometries layer-by-layer. The goal of...

  1. IGBT Fuses for Protection Against Explosion in Voltage Source Converters

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Iov, Florin; Rasmussen, H.

    2004-01-01

    The consequences of electrical faults can be severe; not only to the equipment, but also in the worse case, to people if safety principles are not observed. Every year new applications based on DC-link Voltage Source Converters are added and the demand for protection of power electronics increases...... regarding the high-power IGBT modules. Due to the fact that the power level increases more energy is stored in the DC-link and even with an active protection, a high-power IGBT still has a risk of case rupture (explode) when a circuit failure condition occurs. A possible solution is a protection...... of the converter with standard High Speed Fuses or High Speed IGBT fuses. It is discussed that protection can be achieved by introduction of IGBT fuse located in the DC-link. Experiments show that explosion can be avoided by use of High Speed Fuse protection and the added inductance of standard High Speed...

  2. Image Segmentation by Hierarchical Spatial and Color Spaces Clustering

    Institute of Scientific and Technical Information of China (English)

    YU Wei

    2005-01-01

    Image segmentation, as a basic building block for many high-level image analysis problems, has attracted many research attentions over years. Existing approaches, however, are mainly focusing on the clustering analysis in the single channel information, i.e., either in color or spatial space, which may lead to unsatisfactory segmentation performance. Considering the spatial and color spaces jointly, this paper proposes a new hierarchical image segmentation algorithm, which alternately clusters the image regions in color and spatial spaces in a fine to coarse manner. Without losing the perceptual consistence, the proposed algorithm achieves the segmentation result using only very few number of colors according to user specification.

  3. Effects of Vacuum of Fused Silica UV Damage

    Institute of Scientific and Technical Information of China (English)

    XU Shi-Zhen; LV Hai-Bing; YUAN Xiao-Dong; HUANG Jin; JIANG Xiao-Dong; WANG Hai-Jun; ZU Xiao-Tao; ZHENG Wan-Guo

    2008-01-01

    Damage points induced by 355 nm laser irradiation increase more quickly on the surface of fused silica in vacuum of about 10-3Pa than in atmospheric air at the same fluence.The larger concentration of point defects in vacuum is confirmed by photoluminescence intensity.X-ray photoelectron spectroscopy and infrared absorption indicate the formation of sub-stoichiometric sillca on the surface.The degradation mechanism of fused silica in vacuum is discussed.

  4. Fusing Manual and Machine Feedback in Biomedical Domain

    Science.gov (United States)

    2014-11-01

    Fusing manual and machine feedback in biomedical domain 1Jainisha Sankhavara, 1Fenny Thakrar, 2Shamayeeta Sarkar, 1Prasenjit Majumder 1DA-IICT...to obtain efficient biomedical document retrieval. We focused on fusing manual and machine feedback runs. Fusion run performs better and gives...retrieval of biomedical articles relevant for answering generic clini- cal questions about medical records. There are 30 topics provided, each

  5. ENDODONTIC MANAGEMENT OF FUSED MAXILLARY LATERAL INCISOR: A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Wavdhane

    2014-11-01

    Full Text Available Fusion is a rare occurrence and its definitive diagnosis is of prime importance for successful root canal treatment. This case report discusses the endodontic and esthetic management of fused maxillary right lateral incisor. Root canal treatment was performed on the fused tooth. Nickel Chromium with ceramic crown was fabricated in the shape of lateral incisor. The patient remained asymptomatic and there was a reduction in the size of periapical radiolucency after six months.

  6. A coordinate-wise optimization algorithm for the Fused Lasso

    OpenAIRE

    Höfling, Holger; Binder, Harald; Schumacher, Martin

    2010-01-01

    L1 -penalized regression methods such as the Lasso (Tibshirani 1996) that achieve both variable selection and shrinkage have been very popular. An extension of this method is the Fused Lasso (Tibshirani and Wang 2007), which allows for the incorporation of external information into the model. In this article, we develop new and fast algorithms for solving the Fused Lasso which are based on coordinate-wise optimization. This class of algorithms has recently been applied very successfully to so...

  7. Global equation of state for a glassy material: Fused silica

    Energy Technology Data Exchange (ETDEWEB)

    Boettger, J.C.

    1994-09-01

    A new SESAME equation of state (EOS) for fused silica has been generated using the computer program GRIZZLY and will be added to the SESAME library as material number 7387. This new EOS provides better agreement with experimental data than was achieved by all previous SESAME EOSs for fused silica. Material number 7387 also constitutes the most realistic SESAME-type EOS generated for any glassy material thus far.

  8. Fusing Social Media and Mobile Analytics for Urban Sense Making

    Science.gov (United States)

    2017-05-09

    AFRL-AFOSR-JP-TR-2017-0037 Fusing Social Media and Mobile Analytics for Urban Sense-Making Archan Misra SINGAPORE MANAGEMENT UNIVERSITY Final Report...Final 3. DATES COVERED (From - To) 11 Dec 2013 to 10 Dec 2016 4. TITLE AND SUBTITLE Fusing Social Media and Mobile Analytics for Urban Sense-Making 5a...UNLIMITED: PB Public Release 13. SUPPLEMENTARY NOTES 14. ABSTRACT The proposed research was motivated by the observation that urban environments are

  9. GPS Control Segment

    Science.gov (United States)

    2015-04-29

    Luke J. Schaub Chief, GPS Control Segment Division 29 Apr 15 GPS Control Segment Report Documentation Page Form ApprovedOMB No. 0704-0188...00-2015 4. TITLE AND SUBTITLE GPS Control Segment 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT...Center, GPS Control Segment Division,Los Angeles AFB, El Segundo,CA,90245 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S

  10. Sipunculans and segmentation

    DEFF Research Database (Denmark)

    Wanninger, Andreas; Kristof, Alen; Brinkmann, Nora

    2009-01-01

    Comparative molecular, developmental and morphogenetic analyses show that the three major segmented animal groups- Lophotrochozoa, Ecdysozoa and Vertebrata-use a wide range of ontogenetic pathways to establish metameric body organization. Even in the life history of a single specimen, different...... plasticity and potential evolutionary lability of segmentation nourishes the controversy of a segmented bilaterian ancestor versus multiple independent evolution of segmentation in respective metazoan lineages....

  11. Automatic Melody Segmentation

    NARCIS (Netherlands)

    Rodríguez López, Marcelo

    2016-01-01

    The work presented in this dissertation investigates music segmentation. In the field of Musicology, segmentation refers to a score analysis technique, whereby notated pieces or passages of these pieces are divided into “units” referred to as sections, periods, phrases, and so on. Segmentation analy

  12. The Concept of Segmented Wind Turbine Blades: A Review

    Directory of Open Access Journals (Sweden)

    Mathijs Peeters

    2017-07-01

    Full Text Available There is a trend to increase the length of wind turbine blades in an effort to reduce the cost of energy (COE. This causes manufacturing and transportation issues, which have given rise to the concept of segmented wind turbine blades. In this concept, multiple segments can be transported separately. While this idea is not new, it has recently gained renewed interest. In this review paper, the concept of wind turbine blade segmentation and related literature is discussed. The motivation for dividing blades into segments is explained, and the cost of energy is considered to obtain requirements for such blades. An overview of possible implementations is provided, considering the split location and orientation, as well as the type of joint to be used. Many implementations draw from experience with similar joints such as the joint at the blade root, hub and root extenders and joints used in rotor tips and glider wings. Adhesive bonds are expected to provide structural and economic efficiency, but in-field assembly poses a big issue. Prototype segmented blades using T-bolt joints, studs and spar bridge concepts have proven successful, as well as aerodynamically-shaped root and hub extenders.

  13. Caudal migration and proliferation of renal progenitors regulates early nephron segment size in zebrafish

    Science.gov (United States)

    Naylor, Richard W.; Dodd, Rachel C.; Davidson, Alan J.

    2016-01-01

    The nephron is the functional unit of the kidney and is divided into distinct proximal and distal segments. The factors determining nephron segment size are not fully understood. In zebrafish, the embryonic kidney has long been thought to differentiate in situ into two proximal tubule segments and two distal tubule segments (distal early; DE, and distal late; DL) with little involvement of cell movement. Here, we overturn this notion by performing lineage-labelling experiments that reveal extensive caudal movement of the proximal and DE segments and a concomitant compaction of the DL segment as it fuses with the cloaca. Laser-mediated severing of the tubule, such that the DE and DL are disconnected or that the DL and cloaca do not fuse, results in a reduction in tubule cell proliferation and significantly shortens the DE segment while the caudal movement of the DL is unaffected. These results suggest that the DL mechanically pulls the more proximal segments, thereby driving both their caudal extension and their proliferation. Together, these data provide new insights into early nephron morphogenesis and demonstrate the importance of cell movement and proliferation in determining initial nephron segment size. PMID:27759103

  14. Action and gait recognition from recovered 3-D human joints.

    Science.gov (United States)

    Gu, Junxia; Ding, Xiaoqing; Wang, Shengjin; Wu, Youshou

    2010-08-01

    A common viewpoint-free framework that fuses pose recovery and classification for action and gait recognition is presented in this paper. First, a markerless pose recovery method is adopted to automatically capture the 3-D human joint and pose parameter sequences from volume data. Second, multiple configuration features (combination of joints) and movement features (position, orientation, and height of the body) are extracted from the recovered 3-D human joint and pose parameter sequences. A hidden Markov model (HMM) and an exemplar-based HMM are then used to model the movement features and configuration features, respectively. Finally, actions are classified by a hierarchical classifier that fuses the movement features and the configuration features, and persons are recognized from their gait sequences with the configuration features. The effectiveness of the proposed approach is demonstrated with experiments on the Institut National de Recherche en Informatique et Automatique Xmas Motion Acquisition Sequences data set.

  15. Joint purpose?

    DEFF Research Database (Denmark)

    Pristed Nielsen, Helene

    2013-01-01

    Starting from Crenshaw´s point that antiracism often fails to interrogate patriarchy and that feminism often reproduces racist practices (1991: 1252), this paper asks: What are the theoretical reasons for believing that feminism and anti-racism can be regarded as fighting for the joint purpose of...

  16. What is a segment?

    Science.gov (United States)

    Hannibal, Roberta L; Patel, Nipam H

    2013-12-17

    Animals have been described as segmented for more than 2,000 years, yet a precise definition of segmentation remains elusive. Here we give the history of the definition of segmentation, followed by a discussion on current controversies in defining a segment. While there is a general consensus that segmentation involves the repetition of units along the anterior-posterior (a-p) axis, long-running debates exist over whether a segment can be composed of only one tissue layer, whether the most anterior region of the arthropod head is considered segmented, and whether and how the vertebrate head is segmented. Additionally, we discuss whether a segment can be composed of a single cell in a column of cells, or a single row of cells within a grid of cells. We suggest that 'segmentation' be used in its more general sense, the repetition of units with a-p polarity along the a-p axis, to prevent artificial classification of animals. We further suggest that this general definition be combined with an exact description of what is being studied, as well as a clearly stated hypothesis concerning the specific nature of the potential homology of structures. These suggestions should facilitate dialogue among scientists who study vastly differing segmental structures.

  17. 3-D finite element model for destruction process of segment joints of shield tunnel using elastoplastic and damage constitutive methods%盾构管片接头破坏的弹塑性-损伤三维有限元模型研究

    Institute of Scientific and Technical Information of China (English)

    庄晓莹; 张雪健; 朱合华

    2015-01-01

    分别采用弹塑性本构和弹塑性损伤本构,建立盾构管片接头三维有限元模型,模拟正负弯矩下接头压弯破坏全过程.与实验对比后表明:初始加减阶段采用弹塑性本构和损伤本构得到的结构变形曲线基本重合,且与试验值吻合较好;荷载进一步加大后,采用损伤本构进行分析,其结果更接近试验值,且可更好地模拟结构承载力下降过程.通过有限元网格的收敛性分析,证明网格划分的合理性并给出此类有限元模型网格大小的建议值.最后根据数值模拟结果给出管片接头健康评价指标.%Using the elastoplastic and damage constitutive methods for concrete respectively, a 3-D FEM model for segment joints of shield tunnel is established to simulate the process of bending failure under positive and negative loads. By comparing the simulated results with the experimental data, at the initial stage, the deformation curve is almost coincident with the FEM using the elastoplastic and damage constitutive methods, and both of them show a good agreement with the test results. With the increasing load, the results using the damage constitutive method are closer to the experimental values, and it can simulate the dropping process of structural bearing capacity better. Through the convergence analysis of FEM, the rationality of mesh generation is proved, and the grid sizes of similar element models are suggested. Finally, based on the simulated results, some evaluation indices for health assessment of segment joints are proposed.

  18. Compensation of Magnetic Disturbances Improves Inertial and Magnetic Sensing of Human Body Segment Orientation

    NARCIS (Netherlands)

    Roetenberg, Daniel; Luinge, Henk; Baten, Chris T.M.; Veltink, Peter H.

    2005-01-01

    This paper describes a complementary Kalman filter design to estimate orientation of human body segments by fusing gyroscope, accelerometer, and magnetometer signals from miniature sensors. Ferromagnetic materials or other magnetic fields near the sensor module disturb the local earth magnetic field

  19. Fused Lasso Screening Rules via the Monotonicity of Subdifferentials.

    Science.gov (United States)

    Wang, Jie; Fan, Wei; Ye, Jieping

    2015-09-01

    Fused Lasso is a popular regression technique that encodes the smoothness of the data. It has been applied successfully to many applications with a smooth feature structure. However, the computational cost of the existing solvers for fused Lasso is prohibitive when the feature dimension is extremely large. In this paper, we propose novel screening rules that are able to quickly identity the adjacent features with the same coefficients. As a result, the number of variables to be estimated can be significantly reduced, leading to substantial savings in computational cost and memory usage. To the best of our knowledge, the proposed approach is the first attempt to develop screening methods for the fused Lasso problem with general data matrix. Our major contributions are: 1) we derive a new dual formulation of fused Lasso that comes with several desirable properties; 2) we show that the new dual formulation of fused Lasso is equivalent to that of the standard Lasso by two affine transformations; 3) we propose a novel framework for developing effective and efficient screening rules for fused Lasso via the monotonicity of the subdifferentials (FLAMS). Some appealing features of FLAMS are: 1) our methods are safe in the sense that the detected adjacent features are guaranteed to have the same coefficients; 2) the dataset needs to be scanned only once to run the screening, whose computational cost is negligible compared to that of solving the fused Lasso; (3) FLAMS is independent of the solvers and can be integrated with any existing solvers. We have evaluated the proposed FLAMS rules on both synthetic and real datasets. The experiments indicate that FLAMS is very effective in identifying the adjacent features with the same coefficients. The speedup gained by FLAMS can be orders of magnitude.

  20. Shape-Tailored Features and their Application to Texture Segmentation

    KAUST Repository

    Khan, Naeemullah

    2014-04-01

    Texture Segmentation is one of the most challenging areas of computer vision. One reason for this difficulty is the huge variety and variability of textures occurring in real world, making it very difficult to quantitatively study textures. One of the key tools used for texture segmentation is local invariant descriptors. Texture consists of textons, the basic building block of textures, that may vary by small nuisances like illumination variation, deformations, and noise. Local invariant descriptors are robust to these nuisances making them beneficial for texture segmentation. However, grouping dense descriptors directly for segmentation presents a problem: existing descriptors aggregate data from neighborhoods that may contain different textured regions, making descriptors from these neighborhoods difficult to group, leading to significant errors in segmentation. This work addresses this issue by proposing dense local descriptors, called Shape-Tailored Features, which are tailored to an arbitrarily shaped region, aggregating data only within the region of interest. Since the segmentation, i.e., the regions, are not known a-priori, we propose a joint problem for Shape-Tailored Features and the regions. We present a framework based on variational methods. Extensive experiments on a new large texture dataset, which we introduce, show that the joint approach with Shape-Tailored Features leads to better segmentations over the non-joint non Shape-Tailored approach, and the method out-performs existing state-of-the-art.

  1. Segment lengths influence hill walking strategies.

    Science.gov (United States)

    Sheehan, Riley C; Gottschall, Jinger S

    2014-08-22

    Segment lengths are known to influence walking kinematics and muscle activity patterns. During level walking at the same speed, taller individuals take longer, slower strides than shorter individuals. Based on this, we sought to determine if segment lengths also influenced hill walking strategies. We hypothesized that individuals with longer segments would display more joint flexion going uphill and more extension going downhill as well as greater lateral gastrocnemius and vastus lateralis activity in both directions. Twenty young adults of varying heights (below 155 cm to above 188 cm) walked at 1.25 m/s on a level treadmill as well as 6° and 12° up and downhill slopes while we collected kinematic and muscle activity data. Subsequently, we ran linear regressions for each of the variables with height, leg, thigh, and shank length. Despite our population having twice the anthropometric variability, the level and hill walking patterns matched closely with previous studies. While there were significant differences between level and hill walking, there were few hill walking variables that were correlated with segment length. In support of our hypothesis, taller individuals had greater knee and ankle flexion during uphill walking. However, the majority of the correlations were between tibialis anterior and lateral gastrocnemius activities and shank length. Contrary to our hypothesis, relative step length and muscle activity decreased with segment length, specifically shank length. In summary, it appears that individuals with shorter segments require greater propulsion and toe clearance during uphill walking as well as greater braking and stability during downhill walking.

  2. 30 CFR 56.12037 - Fuses in high-potential circuits.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fuses in high-potential circuits. 56.12037... § 56.12037 Fuses in high-potential circuits. Fuse tongs or hot line tools shall be used when fuses are removed or replaced in high-potential circuits....

  3. 30 CFR 57.12037 - Fuses in high-potential circuits.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fuses in high-potential circuits. 57.12037... Electricity Surface and Underground § 57.12037 Fuses in high-potential circuits. Fuse tongs or hotline tools, shall be used when fuses are removed or replaced in high-potential circuits....

  4. 基于策略消费者行为和市场细分的联合定价库存策略%Joint Ordering and Pricing Policy Considering Consumer Behavior and Market Segmentation

    Institute of Scientific and Technical Information of China (English)

    徐贤浩; 陈雯; 彭红雯

    2012-01-01

    策略消费者的行为越来越受到厂商的重视,本文在假设消费者为风险规避型,对商品评价异质,考虑策略消费者和非策略消费者并存的细分市场上,比较两阶段定价和单一定价的优劣,研究限量策略实施的条件,进一步扩展至厂商能同时决定库存和价格的情况。研究表明消费者为风险规避型时,两阶段定价策略优于单一定价策略;策略消费者所占比例越大,消费者风险规避程度越高,第二阶段价格折扣越大,厂商越青睐限量的两阶段定价策略。此外,制定适度的价格折扣才会使厂商增加利润,过度的折扣竞争对厂商和消费者都没有好处。%Strategic consumer behavior has received more and more attention. In this article, consumers are assumed to be risk averse and heterogeneous in product's value. When strategic and non-strategic consum- ers coexist, two-stage pricing policy and single pricing policy are compared, condition of rationing is dis- cussed, and jointly ordering and pricing policy are analyzed. Research shows that two-stage pricing policy dominates single pricing policy when consumers are risk averse. Firm prefers rationing inventory policy if there is higher proportion of strategic consumers or higher degree of risk aversion or greater discount of second phase's price. In addition, only appropriate discounts will increase firm's profit, excessive discount competition doesn't benefit both firm and consumers.

  5. Quantification of Residual Stress from Photonic Signatures of Fused Silica

    Science.gov (United States)

    Cramer, K. Elliott; Hayward, Maurice; Yost, William E.

    2013-01-01

    A commercially available grey-field polariscope (GFP) instrument for photoelastic examination is used to assess impact damage inflicted upon the outer-most pane of Space Shuttle windows made from fused silica. A method and apparatus for calibration of the stress-optic coefficient using four-point bending is discussed. The results are validated on known material (acrylic) and are found to agree with literature values to within 6%. The calibration procedure is then applied to fused-silica specimens and the stress-optic coefficient is determined to be 2.43 +/- 0.54 x 10(exp -12)/Pa. Fused silica specimens containing impacts artificially made at NASA's Hypervelocity Impact Technology Facility (HIT-F), to simulate damage typical during space flight, are examined. The damage sites are cored from fused silica window carcasses and examined with the GFP. The calibrated GFP measurements of residual stress patterns surrounding the damage sites are presented. Keywords: Glass, fused silica, photoelasticity, residual stress

  6. Joint selection of time segment and frequency band for classifying multiclass motor imagery EEG data%基于时间段和频带联合选择的多类运动想象脑电数据分类

    Institute of Scientific and Technical Information of China (English)

    魏庆国; 韩仁香

    2014-01-01

    The time and frequency intervals of EEG signals have significant influence on the classification performance of brain-computer interfaces(BCIs).Based on joint selection of time segment and frequency band,a new classification algorithm was proposed to classify multiclass motor imagery BCI systems in this paper.A sliding window was firstly used to segment the EEG signals in time and frequency domain.Then the multiclass common spatial pattern(CSP)was utilized for feature extraction in each pair of time and fre-quency segment.Finally we employed the k-nearest neighbor(KNN)to classify the extracted feature sig-nals.Cross-validated classification accuracy was used for the selection criterion of optimal time and frequen-cy segment.The performance of the algorithm was tested and compared with those of three typical algo-rithms by a classification experiment on a four-class data set.The results suggested that the algorithm could achieve a highest accuracy rate,validating the effectiveness of the j oint selection of time segment and frequency band based classification algorithm.%脑电信号的时间和频率间隔选择对脑机接口的分类性能具有重要的影响。针对多类运动想象脑机接口系统,提出一个新的基于时间段和频带联合选择的分类算法。该算法首先使用滑动窗将运动想象产生的脑电信号在时域和频域进行分割,然后在每一对截取的时间段和频段,使用多类共空域模式算法提取脑电特征信号,最后使用k-最近邻算法对特征信号进行分类。交叉验证的分类识别率作为最优时间段和频带的选择标准。使用一个四类数据集对这个分类算法的性能进行了测试。与现有的3个典型算法比较,这个算法取得了最高的平均分类正确率,证实了这个基于时间段和频带联合选择的分类算法的有效性。

  7. On Fusing Recursive Traversals of K-d Trees

    Energy Technology Data Exchange (ETDEWEB)

    Rajbhandari, Samyam; Kim, Jinsung; Krishnamoorthy, Sriram; Pouchet, Louis-Noel; Rastello, Fabrice; Harrison, Robert J.; Sadayappan, Ponnuswamy

    2016-03-17

    Loop fusion is a key program transformation for data locality optimization that is implemented in production compilers. But optimizing compilers currently cannot exploit fusion opportunities across a set of recursive tree traversal computations with producer-consumer relationships. In this paper, we develop a compile-time approach to dependence characterization and program transformation to enable fusion across recursively specified traversals over k-ary trees. We present the FuseT source-to-source code transformation framework to automatically generate fused composite recursive operators from an input program containing a sequence of primitive recursive operators. We use our framework to implement fused operators for MADNESS, Multiresolution Adaptive Numerical Environment for Scientific Simulation. We show that locality optimization through fusion can offer more than an order of magnitude performance improvement.

  8. Keypoint Transfer Segmentation

    OpenAIRE

    Wachinger, C.; Toews, M.; Langs, G.; Wells, W.; Golland, P.

    2015-01-01

    We present an image segmentation method that transfers label maps of entire organs from the training images to the novel image to be segmented. The transfer is based on sparse correspondences between keypoints that represent automatically identified distinctive image locations. Our segmentation algorithm consists of three steps: (i) keypoint matching, (ii) voting-based keypoint labeling, and (iii) keypoint-based probabilistic transfer of organ label maps. We introduce generative models for th...

  9. Surface wave propagation effects on buried segmented pipelines

    Directory of Open Access Journals (Sweden)

    Peixin Shi

    2015-08-01

    Full Text Available This paper deals with surface wave propagation (WP effects on buried segmented pipelines. Both simplified analytical model and finite element (FE model are developed for estimating the axial joint pullout movement of jointed concrete cylinder pipelines (JCCPs of which the joints have a brittle tensile failure mode under the surface WP effects. The models account for the effects of peak ground velocity (PGV, WP velocity, predominant period of seismic excitation, shear transfer between soil and pipelines, axial stiffness of pipelines, joint characteristics, and cracking strain of concrete mortar. FE simulation of the JCCP interaction with surface waves recorded during the 1985 Michoacan earthquake results in joint pullout movement, which is consistent with the field observations. The models are expanded to estimate the joint axial pullout movement of cast iron (CI pipelines of which the joints have a ductile tensile failure mode. Simplified analytical equation and FE model are developed for estimating the joint pullout movement of CI pipelines. The joint pullout movement of the CI pipelines is mainly affected by the variability of the joint tensile capacity and accumulates at local weak joints in the pipeline.

  10. Shape-constrained multi-atlas based segmentation with multichannel registration

    Science.gov (United States)

    Hao, Yongfu; Jiang, Tianzi; Fan, Yong

    2012-02-01

    Multi-atlas based segmentation methods have recently attracted much attention in medical image segmentation. The multi-atlas based segmentation methods typically consist of three steps, including image registration, label propagation, and label fusion. Most of the recent studies devote to improving the label fusion step and adopt a typical image registration method for registering atlases to the target image. However, the existing registration methods may become unstable when poor image quality or high anatomical variance between registered image pairs involved. In this paper, we propose an iterative image segmentation and registration procedure to simultaneously improve the registration and segmentation performance in the multi-atlas based segmentation framework. Particularly, a two-channel registration method is adopted with one channel driven by appearance similarity between the atlas image and the target image and the other channel optimized by similarity between atlas label and the segmentation of the target image. The image segmentation is performed by fusing labels of multiple atlases. The validation of our method on hippocampus segmentation of 30 subjects containing MR images with both 1.5T and 3.0T field strength has demonstrated that our method can significantly improve the segmentation performance with different fusion strategies and obtain segmentation results with Dice overlap of 0.892+/-0.024 for 1.5T images and 0.902+/-0.022 for 3.0T images to manual segmentations.

  11. Universal Numeric Segmented Display

    CERN Document Server

    Azad, Md Abul kalam; Kamruzzaman, S M

    2010-01-01

    Segmentation display plays a vital role to display numerals. But in today's world matrix display is also used in displaying numerals. Because numerals has lots of curve edges which is better supported by matrix display. But as matrix display is costly and complex to implement and also needs more memory, segment display is generally used to display numerals. But as there is yet no proposed compact display architecture to display multiple language numerals at a time, this paper proposes uniform display architecture to display multiple language digits and general mathematical expressions with higher accuracy and simplicity by using a 18-segment display, which is an improvement over the 16 segment display.

  12. Bionic Control of Cheetah Bounding with a Segmented Spine

    OpenAIRE

    Chunlei Wang; Shigang Wang

    2016-01-01

    A cheetah model is built to mimic real cheetah and its mechanical and dimensional parameters are derived from the real cheetah. In particular, two joints in spine and four joints in a leg are used to realize the motion of segmented spine and segmented legs which are the key properties of the cheetah bounding. For actuating and stabilizing the bounding gait of cheetah, we present a bioinspired controller based on the state-machine. The controller mainly mimics the function of the cerebellum to...

  13. Bionic Control of Cheetah Bounding with a Segmented Spine

    OpenAIRE

    Chunlei Wang; Shigang Wang

    2016-01-01

    A cheetah model is built to mimic real cheetah and its mechanical and dimensional parameters are derived from the real cheetah. In particular, two joints in spine and four joints in a leg are used to realize the motion of segmented spine and segmented legs which are the key properties of the cheetah bounding. For actuating and stabilizing the bounding gait of cheetah, we present a bioinspired controller based on the state-machine. The controller mainly mimics the function of the cerebellum to...

  14. Aromaticity Competition in Differentially Fused Borepin-Containing Polycyclic Aromatics.

    Science.gov (United States)

    Messersmith, Reid E; Siegler, Maxime A; Tovar, John D

    2016-07-01

    This report describes the synthesis and characterization of a series of borepin-based polycyclic aromatics bearing two different arene fusions. The borepin synthesis features streamlined Ti-mediated alkyne reduction, leading to Z-olefins, followed by direct lithiation and borepin formation. These molecules allow for an assessment of aromatic competition between the fused rings and the central borepin core. Crystallographic, magnetic, and computational studies yielded insights about the aromaticity of novel, differentially fused [b,f]borepins and allowed for comparison to literature compounds. Multiple borepin motifs were also incorporated into polycyclic aromatics with five or six rings in the main backbone, and their properties were also evaluated.

  15. Bonding energy of Sylgard on fused quartz: an experimental investigation

    Science.gov (United States)

    Liu, C.; Yeager, J. D.; Ramos, K. J.

    2015-02-01

    The bonding energy between the polymer Sylgard and fused quartz is determined experimentally using a miniature bulge test combined with three-dimensional digital image correlation (3D-DIC). Based on the experimental observation, Mindlin plate theory is used to compute the bonding energy (adhesive energy or surface energy) between the Sylgard and the fused quartz. The experimental results demonstrate that the combination of the miniature bulge test and the 3D-DIC provides a viable tool to directly measure interfacial and bonding properties.

  16. Iatrogenic mid-root perforation of fused teeth

    Directory of Open Access Journals (Sweden)

    Vijay Kumar

    2012-01-01

    Full Text Available Fusion is defined as a union between the dentin and/or enamel of two or more distinct dental sprouts that occurs at any stage of the dental organ. Its prevalence ranges from 0.5%-2.5% in the primary dentition alone and 0.1%-1% of the primary as well as the permanent dentition. These fused teeth can cause various problems such as caries, periodontal disease, abnormal eruption, impaction or an ectopic eruption of an adjacent tooth and reported in the literature. However this paper documented an unusual case of iatrogenic root perforation of fused permanent lower anterior teeth during inter maxillary fixation.

  17. Segmentation and Estimation of Change-point Models

    OpenAIRE

    Fang, Xiao; Li, Jian; Siegmund, David

    2016-01-01

    To segment a sequence of independent random variables at an unknown number of change-points, we introduce new procedures that are based on thresholding the likelihood ratio statistic. We also study confidence regions based on the likelihood ratio statistic for the changepoints and joint confidence regions for the change-points and the parameter values. Applications to segment an array CGH analysis of the BT474 cell line are discussed.

  18. Segmentation of human upper body movement using multiple IMU sensors.

    Science.gov (United States)

    Aoki, Takashi; Lin, Jonathan Feng-Shun; Kulic, Dana; Venture, Gentiane

    2016-08-01

    This paper proposes an approach for the segmentation of human body movements measured by inertial measurement unit sensors. Using the angular velocity and linear acceleration measurements directly, without converting to joint angles, we perform segmentation by formulating the problem as a classification problem, and training a classifier to differentiate between motion end-point and within-motion points. The proposed approach is validated with experiments measuring the upper body movement during reaching tasks, demonstrating classification accuracy of over 85.8%.

  19. Streamline segment scaling behavior in a turbulent wavy channel flow

    Science.gov (United States)

    Rubbert, A.; Hennig, F.; Klaas, M.; Pitsch, H.; Schröder, W.; Peters, N.

    2017-02-01

    A turbulent flow in a wavy channel was investigated by tomographic particle-image velocimetry measurements and direct numerical simulations. To analyze the turbulent structures and their scaling behavior in a flow undergoing favorable and adverse pressure gradients, the streamline segmentation method proposed by Wang (J Fluid Mech 648:183-203, 2010) was employed. This method yields joint statistical information about velocity fluctuations and length scale distributions of non-overlapping structures within the flow. In particular, the joint statistical properties are notably influenced by the pressure distribution. Previous findings from flat channel flows and synthetic turbulence simulations concerning the normalized segment length distribution could be reproduced and therefore appear to be largely universal. However, the mean streamline segment length of accelerating and decelerating segments varies within one wavelength typically elongating segments of the type which corresponds to the local mean flow. Furthermore, the local pressure gradient was found to significantly impact local joint streamline segmentation statistics as a main influence on their inherent asymmetry.

  20. Joint purpose?

    DEFF Research Database (Denmark)

    Pristed Nielsen, Helene

    2013-01-01

    of anti-discrimination in Europe today? And what empirical evidence may be found for such a joint approach? The paper discusses how the contemporary EU context differs from the American context which prompted Crenshaw to raise the point about intersectionality, and it analyses documents and interviews...... from each of the two European umbrella organisations the European Women´s Lobby and the European Network against Racism, as well as a number of their national member organisations from across Europe, both within EU and non-EU member states....

  1. From interpretation to segmentation

    NARCIS (Netherlands)

    Koning, A.R.; Lier, R.J. van

    2005-01-01

    In visual perception, part segmentation of an object is considered to be guided by image-based properties, such as occurrences of deep concavities in the outer contour. However, object-based properties can also provide information regarding segmentation. In this study, outer contours and interpretat

  2. Segmentation, advertising and prices

    NARCIS (Netherlands)

    Galeotti, Andrea; Moraga González, José

    This paper explores the implications of market segmentation on firm competitiveness. In contrast to earlier work, here market segmentation is minimal in the sense that it is based on consumer attributes that are completely unrelated to tastes. We show that when the market is comprised by two

  3. Segmentation, advertising and prices

    NARCIS (Netherlands)

    Galeotti, Andrea; Moraga González, José

    2008-01-01

    This paper explores the implications of market segmentation on firm competitiveness. In contrast to earlier work, here market segmentation is minimal in the sense that it is based on consumer attributes that are completely unrelated to tastes. We show that when the market is comprised by two consume

  4. Benign segmental bronchial obstruction

    Energy Technology Data Exchange (ETDEWEB)

    Loercher, U.

    1988-09-01

    The benigne segmental bronchial obstruction - mostly discovered on routine chest films - can well be diagnosed by CT. The specific findings in CT are the site of the bronchial obstruction, the mucocele and the localized empysema of the involved segment. Furthermore CT allows a better approach to the underlying process.

  5. Hospital benefit segmentation.

    Science.gov (United States)

    Finn, D W; Lamb, C W

    1986-12-01

    Market segmentation is an important topic to both health care practitioners and researchers. The authors explore the relative importance that health care consumers attach to various benefits available in a major metropolitan area hospital. The purposes of the study are to test, and provide data to illustrate, the efficacy of one approach to hospital benefit segmentation analysis.

  6. Investigation of the corrosion performance of different braze fillers fused onto stainless steel type 1.4401 (UNS S31600)

    Energy Technology Data Exchange (ETDEWEB)

    Wolfe, C.; Eklund, T.; Persson, O. [Alfa Laval Corporate AB, Tumba (Sweden)

    2004-07-01

    Corrosion measurements were performed on a new iron based braze filler, AlfaNova{sup 1} developed by Alfa Laval. The braze filler was fused onto stainless steel type EN 1.4401 (UNS S31600). The susceptibility to general corrosion, intergranular corrosion and pitting corrosion was evaluated by gravimetrical and electrochemical methods as well as metallographical examination of the samples. Different sample configurations were utilised, which simulate the geometry of a braze joint in a plate heat exchange. The results were compared with a selection of commercial nickel-based braze fillers. It was shown that the newly developed iron-based braze filler had similar corrosion resistance as the commercially available nickel-based fillers. It was seen that the precipitation of intermetallic phases due to melting point depressants had a governing effect on the corrosion resistance of the braze joint. (orig.)

  7. Construction of five-piece segment using high-fluidity concrete; Koryudo togo bunkatsu segment no seko jisseki

    Energy Technology Data Exchange (ETDEWEB)

    Suda, Y.; Fukuzawa, I.; Matsunaga, H. [Tokyo Electric Power Co. Inc., Tokyo (Japan)

    1998-09-05

    After reviewing RC segment materials and the number of joints required, a segment of five equal pieces using high-fluidity concrete is employed in conduit construction work (for 500kV transmission lines) near Hommoku Wharf, Kanagawa Prefecture, which is for reduction in the shield tunnel construction cost (segment cost rate approximately 1/3). The use of high-fluidity concrete raises the materials cost a little but the factory overhead, expenditures for fabrication and formwork construction are lowered because some working processes may be dispensed with, such as the processes of compaction by vibration, surface finish, and formwork movement, and because the formwork main body may be simplified in structure. Although the standard tunnel specifications mention a segment consisting of 6 pieces, the 5-piece segment adopted in this construction work lowers the cost approximately 20% thanks to reduction in the numbers of joints between segment pieces and between rings. In the shield tunnelling process, assembly is easier and the construction work is executed without hitches deserving special mention. The new technique is comparable to the conventional ones in terms of quality and process management. Since the number of joints per piece between rings is reduced from the 3 in the conventional method to the 2 in this new method, two core-sensing pins are provided per piece between rings for assuring accuracy and shortening time in assembling. 2 refs., 8 figs., 11 tabs.

  8. In situ observation of modulated light emission of fiber fuse synchronized with void train over hetero-core splice point.

    Directory of Open Access Journals (Sweden)

    Shin-ichi Todoroki

    Full Text Available BACKGROUND: Fiber fuse is a process of optical fiber destruction under the action of laser radiation, found 20 years ago. Once initiated, opical discharge runs along the fiber core region to the light source and leaves periodic voids whose shape looks like a bullet pointing the direction of laser beam. The relation between damage pattern and propagation mode of optical discharge is still unclear even after the first in situ observation three years ago. METHODOLOGY/PRINCIPAL FINDINGS: Fiber fuse propagation over hetero-core splice point (Corning SMF-28e and HI 1060 was observed in situ. Sequential photographs obtained at intervals of 2.78 micros recorded a periodic emission at the tail of an optical discharge pumped by 1070 nm and 9 W light. The signal stopped when the discharge ran over the splice point. The corresponding damage pattern left in the fiber core region included a segment free of periodicity. CONCLUSIONS: The spatial modulation pattern of the light emission agreed with the void train formed over the hetero-core splice point. Some segments included a bullet-shaped void pointing in the opposite direction to the laser beam propagation although the sequential photographs did not reveal any directional change in the optical discharge propagation.

  9. Crossed fused renal ectopia: Challenges in diagnosis and management

    Directory of Open Access Journals (Sweden)

    Shailesh Solanki

    2013-01-01

    Full Text Available Aim: Crossed fused renal ectopia is a rare congenital malformation, which is reported to be usually asymptomatic but may have varied presentations. This survey was conducted to study the clinical profile and the challenges posed in the management of this entity. Materials and Methods: Retrospective analysis of 6 patients diagnosed to have crossed fused renal ectopia during 1997-2010. The diagnosis was confirmed during surgical exploration in one patient. In one patient it was detected on antenatal ultrasonography and in the other 4 patients it was detected during investigations for abdominal pain, abdominal mass, anorectal malformation and urinary tract infection. Results: The left moiety was crossed and fused with the right moiety in 4 cases. Ultrasonography was found to be a good screening investigation with useful diagnostic contributions from CT scans, radionuclide scintigraphy and magnetic resonance urography. Micturating cystourethrography revealed presence of VUR in 4 cases, 3 of whom have undergone ureteric reimplantation. Two patients required pyeloplasty for pelviureteric junction obstruction; in one of these patients the upper ureter was entrapped in the isthmus. In one patient, a non-functioning moiety resulted in nephrectomy. All children were asymptomatic at last follow-up with stable renal functions. Conclusions: Crossed fused renal ectopia was detected in most patients during investigation for other problems. It was found more commonly in boys. The left moiety was crossed to the right in the majority of cases. Associated urological problems were found in most cases and required the appropriate surgical management.

  10. Evaluation of a color fused dual-band NVG

    NARCIS (Netherlands)

    Hogervorst, M.A.; Toet, A.

    2009-01-01

    We have tested a prototype dual-band NVG system consisting of two NVGs fitted with filters that split the NVG sensitive range into a short (visual) and a long wavelength (NIR) band. The Color-the-night technique (see Hogervorst & Toet, SPIE D&S ‘08) was used to fuse the images of the two sensors. We

  11. A Review of Variable Slicing in Fused Deposition Modeling

    Science.gov (United States)

    Nadiyapara, Hitesh Hirjibhai; Pande, Sarang

    2016-06-01

    The paper presents a literature survey in the field of fused deposition of plastic wires especially in the field of slicing and deposition using extrusion of thermoplastic wires. Various researchers working in the field of computation of deposition path have used their algorithms for variable slicing. In the study, a flowchart has also been proposed for the slicing and deposition process. The algorithm already been developed by previous researcher will be used to be implemented on the fused deposition modelling machine. To demonstrate the capabilities of the fused deposition modeling machine a case study has been taken. It uses a manipulated G-code to be fed to the fused deposition modeling machine. Two types of slicing strategies, namely uniform slicing and variable slicing have been evaluated. In the uniform slicing, the slice thickness has been used for deposition is varying from 0.1 to 0.4 mm. In the variable slicing, thickness has been varied from 0.1 in the polar region to 0.4 in the equatorial region Time required and the number of slices required to deposit a hemisphere of 20 mm diameter have been compared with that using the variable slicing.

  12. Solid-state recoverable fuse functions as circuit breaker

    Science.gov (United States)

    Thomas, E. F., Jr.

    1966-01-01

    Molded, conductive-epoxy recoverable fuse protects electronic circuits during overload conditions, and then permits them to continue to function immediately after the overload condition is removed. It has low resistance at ambient temperature, and high resistance at an elevated temperature.

  13. Evaluation of a color fused dual-band NVG

    NARCIS (Netherlands)

    Hogervorst, M.A.; Toet, A.

    2009-01-01

    We designed and evaluated a dual-band Night Vision Goggles sensor system. The sensor system consists of two optically aligned NVGs fitted with filters splitting the sensitive range into a visual and a near-infrared band. The Color-the-night technique (Hogervorst & Toet, FUSION2008) was used to fuse

  14. Non-invasive management of fused upper incisors

    Directory of Open Access Journals (Sweden)

    Pouran Samimi

    2012-01-01

    Full Text Available The union of two different dental sprouts which can happen in any phase of dental development is commonly called fusion. This developmental anomaly may cause clinical problems including esthetic impairment, which are mainly treated by endodontic and surgical treatments. There are a few reports of conservative not invasive treatment of fused incisors teeth through restorative or prosthetic techniques. They are rarely reported in mandibular posterior teeth. This paper presents an unusual case of fusion of 7 and 8, and also 9 and 10 teeth which was treated with a nonendodontic and nonsurgical conservative approach. Patient was a healthy18-year-old female with chief complaint of bad-looking teeth that in intraoral examination revealed the fusion of 7 and 8, and also 9 and 10 teeth. The space between the mesial of the 6 and 11 teeth was reconstructed. Diastema between the fused teeth was closed. A new lateral tooth was replaced between the fused teeth (7 and 8 and 6 tooth with direct fiber-reinforced composite. The space between the fused teeth (9 and 10 and also tooth 11 was partially closed. Gingival papillas were reconstructed using pink composite. The mandibular anterior missing teeth were replaced with rochett bridge. At the end of treatment the esthetic of the patient was improved. As the treatment was not invasive, major complications are not expected; however, there is potential for eventual long-term periodontal problems due to poor oral hygiene. Debonding of the rochett bridge may happen as well.

  15. Non-invasive management of fused upper incisors.

    Science.gov (United States)

    Samimi, Pouran; Shirban, Mohammad-Reza; Arbabzadeh-Zavareh, Farahnaz

    2012-01-01

    The union of two different dental sprouts which can happen in any phase of dental development is commonly called fusion. This developmental anomaly may cause clinical problems including esthetic impairment, which are mainly treated by endodontic and surgical treatments. There are a few reports of conservative not invasive treatment of fused incisors teeth through restorative or prosthetic techniques. They are rarely reported in mandibular posterior teeth. This paper presents an unusual case of fusion of 7 and 8, and also 9 and 10 teeth which was treated with a nonendodontic and nonsurgical conservative approach. Patient was a healthy18-year-old female with chief complaint of bad-looking teeth that in intraoral examination revealed the fusion of 7 and 8, and also 9 and 10 teeth. The space between the mesial of the 6 and 11 teeth was reconstructed. Diastema between the fused teeth was closed. A new lateral tooth was replaced between the fused teeth (7 and 8) and 6 tooth with direct fiber-reinforced composite. The space between the fused teeth (9 and 10) and also tooth 11 was partially closed. Gingival papillas were reconstructed using pink composite. The mandibular anterior missing teeth were replaced with rochett bridge. At the end of treatment the esthetic of the patient was improved. As the treatment was not invasive, major complications are not expected; however, there is potential for eventual long-term periodontal problems due to poor oral hygiene. Debonding of the rochett bridge may happen as well.

  16. New developments in fused deposition modeling of ceramics

    DEFF Research Database (Denmark)

    Bellini, Anna; Shor, L.; Guceri, S.I.

    2005-01-01

    Purpose - To shift from rapid prototyping (RP) to agile fabrication by broadening the material selection, e.g. using ceramics, hence improving the properties (e.g. mechanical properties) of fused deposition modeling (FDM) products. Design/methodology/approach - This paper presents the development...

  17. A Bintree Energy Approach for Colour Image Segmentation Using Adaptive Channel Selection

    Institute of Scientific and Technical Information of China (English)

    TU Sheng-xian; ZHANG Su; CHEN Ya-zhu; XIAO Chang-yan; ZHANG Lei

    2008-01-01

    A new hierarchical approach called bintree energy segmentation was presented for color image seg-mentation. The image features are extracted by adaptive clustering on multi-channel data at each level and used as the criteria to dynamically select the best chromatic channel, where the segmentation is carried out. In this approach, an extended direct energy computation method based on the Chan-Vese model was proposed to segment the selected channel, and the segmentation outputs are then fused with other channels into new images,from which a new channel with better features is selected for the second round segmentation. This procedure is repeated until the preset condition is met. Finally, a binary segmentation tree is formed, in which each leaf represents a class of objects with a distinctive color. To facilitate the data organization, image background is employed in segmentation and channels fusion. The bintree energy segmentation exploits color information involved in all channels data and tries to optimize the global segmentation result by choosing the "best" chan-nel for segmentation at each level. The experiments show that the method is effective in speed, accuracy and flexibility.

  18. A wearable system for multi-segment foot kinetics measurement.

    Science.gov (United States)

    Rouhani, H; Favre, J; Crevoisier, X; Aminian, K

    2014-05-01

    This study aims to design a wearable system for kinetics measurement of multi-segment foot joints in long-distance walking and to investigate its suitability for clinical evaluations. The wearable system consisted of inertial sensors (3D gyroscopes and 3D accelerometers) on toes, forefoot, hindfoot, and shank, and a plantar pressure insole. After calibration in a laboratory, 10 healthy elderly subjects and 12 patients with ankle osteoarthritis walked 50m twice wearing this system. Using inverse dynamics, 3D forces, moments, and power were calculated in the joint sections among toes, forefoot, hindfoot, and shank. Compared to those we previously estimated for a one-segment foot model, the sagittal and transverse moments and power in the ankle joint, as measured via multi-segment foot model, showed a normalized RMS difference of less than 11%, 14%, and 13%, respectively, for healthy subjects, and 13%, 15%, and 14%, for patients. Similar to our previous study, the coronal moments were not analyzed. Maxima-minima values of anterior-posterior and vertical force, sagittal moment, and power in shank-hindfoot and hindfoot-forefoot joints were significantly different between patients and healthy subjects. Except for power, the inter-subject repeatability of these parameters was CMC>0.90 for healthy subjects and CMC>0.70 for patients. Repeatability of these parameters was lower for the forefoot-toes joint. The proposed measurement system estimated multi-segment foot joints kinetics with acceptable repeatability but showed difference, compared to those previously estimated for the one-segment foot model. These parameters also could distinguish patients from healthy subjects. Thus, this system is suggested for outcome evaluations of foot treatments.

  19. Keypoint Transfer Segmentation.

    Science.gov (United States)

    Wachinger, C; Toews, M; Langs, G; Wells, W; Golland, P

    2015-01-01

    We present an image segmentation method that transfers label maps of entire organs from the training images to the novel image to be segmented. The transfer is based on sparse correspondences between keypoints that represent automatically identified distinctive image locations. Our segmentation algorithm consists of three steps: (i) keypoint matching, (ii) voting-based keypoint labeling, and (iii) keypoint-based probabilistic transfer of organ label maps. We introduce generative models for the inference of keypoint labels and for image segmentation, where keypoint matches are treated as a latent random variable and are marginalized out as part of the algorithm. We report segmentation results for abdominal organs in whole-body CT and in contrast-enhanced CT images. The accuracy of our method compares favorably to common multi-atlas segmentation while offering a speed-up of about three orders of magnitude. Furthermore, keypoint transfer requires no training phase or registration to an atlas. The algorithm's robustness enables the segmentation of scans with highly variable field-of-view.

  20. Pancreas and cyst segmentation

    Science.gov (United States)

    Dmitriev, Konstantin; Gutenko, Ievgeniia; Nadeem, Saad; Kaufman, Arie

    2016-03-01

    Accurate segmentation of abdominal organs from medical images is an essential part of surgical planning and computer-aided disease diagnosis. Many existing algorithms are specialized for the segmentation of healthy organs. Cystic pancreas segmentation is especially challenging due to its low contrast boundaries, variability in shape, location and the stage of the pancreatic cancer. We present a semi-automatic segmentation algorithm for pancreata with cysts. In contrast to existing automatic segmentation approaches for healthy pancreas segmentation which are amenable to atlas/statistical shape approaches, a pancreas with cysts can have even higher variability with respect to the shape of the pancreas due to the size and shape of the cyst(s). Hence, fine results are better attained with semi-automatic steerable approaches. We use a novel combination of random walker and region growing approaches to delineate the boundaries of the pancreas and cysts with respective best Dice coefficients of 85.1% and 86.7%, and respective best volumetric overlap errors of 26.0% and 23.5%. Results show that the proposed algorithm for pancreas and pancreatic cyst segmentation is accurate and stable.

  1. Segmentation of consumer's markets and evaluation of market's segments

    OpenAIRE

    ŠVECOVÁ, Iveta

    2013-01-01

    The goal of this bachelor thesis was to explain a possibly segmentation of consumer´s markets for a chosen company, and to present a suitable goods offer, so it would be suitable to the needs of selected segments. The work is divided into theoretical and practical part. First part describes marketing, segmentation, segmentation of consumer's markets, consumer's market, market's segments a other terms. Second part describes an evaluation of questionnaire survey, discovering of market's segment...

  2. Implant arthroplasty for the distal radioulnar joint.

    Science.gov (United States)

    Scheker, Luis R

    2008-11-01

    The distal radioulnar joint (DRUJ) is a weight-bearing joint; the ulnar head is frequently excised either totally or partially and in some cases is fused because of degenerative, rheumatoid, or posttraumatic arthritis and treated with a "salvage procedure." The result of these procedures is the inability of those patients to lift even minor weight. Articles about these procedures report the ability to pronate and supinate, but they rarely discuss grip strength or lifting capacity. We present an alternative to the salvage procedures that allows full range of motions as well as the ability to grip and lift weights encountered in daily living, such as a gallon of milk. The Aptis total DRUJ replacement prosthesis (Aptis Medical, Louisville, KY), a bipolar self-stabilizing DRUJ endoprosthesis, restores the forearm function. The technique of implantation is presented here.

  3. Segmentation of antiperspirants and deodorants

    OpenAIRE

    KRÁL, Tomáš

    2009-01-01

    The goal of Master's Thesis on topic Segmentation of antiperspirants and deodorants is to discover differences in consumer's behaviour, determinate and describe segments of consumers based on these differences and propose marketing strategy for the most attractive segments. Theoretical part describes market segmentation in general, process of segmentation and segmentation criteria. Analytic part characterizes Czech market of antiperspirants and deodorants, analyzes ACNielsen market data and d...

  4. a segmentation approach

    African Journals Online (AJOL)

    kirstam

    a visitor survey was conducted at the Cape Town International Jazz ... 13Key words: dining motives, tipping, black diners, market segmentation, South .... and tipping behaviour as well as the findings from cross-cultural tipping and market.

  5. Segmental tuberculosis verrucosa cutis

    Directory of Open Access Journals (Sweden)

    Hanumanthappa H

    1994-01-01

    Full Text Available A case of segmental Tuberculosis Verrucosa Cutis is reported in 10 year old boy. The condition was resembling the ascending lymphangitic type of sporotrichosis. The lesions cleared on treatment with INH 150 mg daily for 6 months.

  6. Joint Compression-Segmentation of functional MRI Data

    DEFF Research Database (Denmark)

    Zhang, N.; Wu, Mo; Forchhammer, Søren

    2005-01-01

    Functional Magnetic Resonance Imaging (fMRI) data sets are four dimensional (4D) and very large in size. Compression can enhance system performance in terms of storage and transmission capacities. Two approaches are investigated: adaptive DPCM and integer wavelets. In the DPCM approach, each voxel...... information. Each voxel time sequence is DPCM coded using a quantized autoregressive model. The prediction residuals are coded by simple Rice coding for high decoder throughput. In the wavelet approach, the 4D fMRI data set is mapped to a 3D data set, with the 3D volume at each time instance being laid out...... into a 2D plane as a slice mosaic. 3D integer wavelet packets are used for lossless compression of fMRI data. The wavelet coefficients are compressed by 3D context-based adaptive arithmetic coding. An object-oriented compression mode is also introduced in the wavelet codec. An elliptic mask combined...

  7. Range and intensity vision for rock-scene segmentation

    CSIR Research Space (South Africa)

    Mkwelo, SG

    2007-11-01

    Full Text Available . We propose a joint analysis of range and intensity images of rocks where sections extracted from range images are used to guide a Model-driven intensity image segmentation process. The models contain rock shape and edge probability information which...

  8. 3D Brain Tumors and Internal Brain Structures Segmentation in MR Images

    Directory of Open Access Journals (Sweden)

    P.NARENDRAN

    2012-02-01

    Full Text Available The main topic of this paper is to segment brain tumors, their components (edema and necrosis and internal structures of the brain in 3D MR images. For tumor segmentation we propose a framework that is a combination of region-based and boundary-based paradigms. In this framework, segment the brain using a method adapted for pathological cases and extract some global information on the tumor by symmetry based histogram analysis. We propose a new and original method that combines region and boundary information in two phases: initialization and refinement. The method relies on symmetry-based histogram analysis. The initial segmentation of the tumor is refined relying on boundary information of the image. We use a deformable model which is again constrained by the fused spatial relations of the structure. The method was also evaluated on 10 contrast enhanced T1-weighted images to segment the ventricles, caudate nucleus and thalamus.

  9. A novel SAR fusion image segmentation method based on triplet Markov field

    Science.gov (United States)

    Wang, Jiajing; Jiao, Shuhong; Sun, Zhenyu

    2015-03-01

    Markov random field (MRF) has been widely used in SAR image segmentation because of the advantage of directly modeling the posterior distribution and suppresses the speckle on the influence of the segmentation result. However, when the real SAR images are nonstationary images, the unsupervised segmentation results by MRF can be poor. The recent proposed triplet Markov field (TMF) model is well appropriate for nonstationary SAR image processing due to the introduction of an auxiliary field which reflects the nonstationarity. In addition, on account of the texture features of SAR image, a fusion image segmentation method is proposed by fusing the gray level image and texture feature image. The effectiveness of the proposed method in this paper is demonstrated by a synthesis SAR image and the real SAR images segmentation experiments, and it is better than the state-of-art methods.

  10. Market segmentation: venezuelan adrs

    OpenAIRE

    Urbi Garay; Maximiliano González

    2012-01-01

    The foreign exchange controls imposed by Venezuela in 2003, constitute a natural experiment that allows researchers to observe the effects of exchange controls on stock market segmentation. This paper provides empirical evidence that, although the Venezuelan capital market as a whole was highly segmented before the controls were imposed, shares in the firm CANTV were, through its American Depositary Receipts (ADRs), partially integrated with the global market. Following the imposition of the ...

  11. Adjacent segment disease.

    Science.gov (United States)

    Virk, Sohrab S; Niedermeier, Steven; Yu, Elizabeth; Khan, Safdar N

    2014-08-01

    EDUCATIONAL OBJECTIVES As a result of reading this article, physicians should be able to: 1. Understand the forces that predispose adjacent cervical segments to degeneration. 2. Understand the challenges of radiographic evaluation in the diagnosis of cervical and lumbar adjacent segment disease. 3. Describe the changes in biomechanical forces applied to adjacent segments of lumbar vertebrae with fusion. 4. Know the risk factors for adjacent segment disease in spinal fusion. Adjacent segment disease (ASD) is a broad term encompassing many complications of spinal fusion, including listhesis, instability, herniated nucleus pulposus, stenosis, hypertrophic facet arthritis, scoliosis, and vertebral compression fracture. The area of the cervical spine where most fusions occur (C3-C7) is adjacent to a highly mobile upper cervical region, and this contributes to the biomechanical stress put on the adjacent cervical segments postfusion. Studies have shown that after fusion surgery, there is increased load on adjacent segments. Definitive treatment of ASD is a topic of continuing research, but in general, treatment choices are dictated by patient age and degree of debilitation. Investigators have also studied the risk factors associated with spinal fusion that may predispose certain patients to ASD postfusion, and these data are invaluable for properly counseling patients considering spinal fusion surgery. Biomechanical studies have confirmed the added stress on adjacent segments in the cervical and lumbar spine. The diagnosis of cervical ASD is complicated given the imprecise correlation of radiographic and clinical findings. Although radiological and clinical diagnoses do not always correlate, radiographs and clinical examination dictate how a patient with prolonged pain is treated. Options for both cervical and lumbar spine ASD include fusion and/or decompression. Current studies are encouraging regarding the adoption of arthroplasty in spinal surgery, but more long

  12. US EPA 2012 Air Quality Fused Surface for the Conterminous U.S. Map Service

    Data.gov (United States)

    U.S. Environmental Protection Agency — This web service contains a polygon layer that depicts fused air quality predictions for 2012 for census tracts in the conterminous United States. Fused air quality...

  13. Strategic market segmentation

    Directory of Open Access Journals (Sweden)

    Maričić Branko R.

    2015-01-01

    Full Text Available Strategic planning of marketing activities is the basis of business success in modern business environment. Customers are not homogenous in their preferences and expectations. Formulating an adequate marketing strategy, focused on realization of company's strategic objectives, requires segmented approach to the market that appreciates differences in expectations and preferences of customers. One of significant activities in strategic planning of marketing activities is market segmentation. Strategic planning imposes a need to plan marketing activities according to strategically important segments on the long term basis. At the same time, there is a need to revise and adapt marketing activities on the short term basis. There are number of criteria based on which market segmentation is performed. The paper will consider effectiveness and efficiency of different market segmentation criteria based on empirical research of customer expectations and preferences. The analysis will include traditional criteria and criteria based on behavioral model. The research implications will be analyzed from the perspective of selection of the most adequate market segmentation criteria in strategic planning of marketing activities.

  14. Skin Images Segmentation

    Directory of Open Access Journals (Sweden)

    Ali E. Zaart

    2010-01-01

    Full Text Available Problem statement: Image segmentation is a fundamental step in many applications of image processing. Skin cancer has been the most common of all new cancers detected each year. At early stage detection of skin cancer, simple and economic treatment can cure it mostly. An accurate segmentation of skin images can help the diagnosis to define well the region of the cancer. The principal approach of segmentation is based on thresholding (classification that is lied to the problem of the thresholds estimation. Approach: The objective of this study is to develop a method to segment the skin images based on a mixture of Beta distributions. We assume that the data in skin images can be modeled by a mixture of Beta distributions. We used an unsupervised learning technique with Beta distribution to estimate the statistical parameters of the data in skin image and then estimate the thresholds for segmentation. Results: The proposed method of skin images segmentation was implemented and tested on different skin images. We obtained very good results in comparing with the same techniques with Gamma distribution. Conclusion: The experiment showed that the proposed method obtained very good results but it requires more testing on different types of skin images.

  15. Pixel-Based Land Cover Classification by Fusing Hyperspectral and LIDAR Data

    Science.gov (United States)

    Jahan, F.; Awrangjeb, M.

    2017-09-01

    Land cover classification has many applications like forest management, urban planning, land use change identification and environment change analysis. The passive sensing of hyperspectral systems can be effective in describing the phenomenology of the observed area over hundreds of (narrow) spectral bands. On the other hand, the active sensing of LiDAR (Light Detection and Ranging) systems can be exploited for characterising topographical information of the area. As a result, the joint use of hyperspectral and LiDAR data provides a source of complementary information, which can greatly assist in the classification of complex classes. In this study, we fuse hyperspectral and LiDAR data for land cover classification. We do a pixel-wise classification on a disjoint set of training and testing samples for five different classes. We propose a new feature combination by fusing features from both hyperspectral and LiDAR, which achieves competent classification accuracy with low feature dimension, while the existing method requires high dimensional feature vector to achieve similar classification result. Also, for the reduction of the dimension of the feature vector, Principal Component Analysis (PCA) is used as it captures the variance of the samples with a limited number of Principal Components (PCs). We tested our classification method using PCA applied on hyperspectral bands only and combined hyperspectral and LiDAR features. Classification with support vector machine (SVM) and decision tree shows that our feature combination achieves better classification accuracy compared to the existing feature combination, while keeping the similar number of PCs. The experimental results also show that decision tree performs better than SVM and requires less execution time.

  16. Joint Replacement (Finger and Wrist Joints)

    Science.gov (United States)

    ... artificial joint Damage to vessels, nerves or other structures in the region of the surgery Alternatives Some alternate procedures for treating arthritis include: Joint injections Oral medications such as aspirin or anti-inflammatory medicines Hand therapy exercises and ...

  17. Fuzzy Modelling of Knee Joint with Genetic Optimization

    Directory of Open Access Journals (Sweden)

    B. S. K. K. Ibrahim

    2011-01-01

    Full Text Available Modelling of joint properties of lower limbs in people with spinal cord injury is significantly challenging for researchers due to the complexity of the system. The objective of this study is to develop a knee joint model capable of relating electrical parameters to dynamic joint torque as well as knee angle for functional electrical stimulation application. The joint model consists of a segmental dynamic, time-invariant passive properties and uncertain time-variant active properties. The knee joint model structure comprising optimised equations of motion and fuzzy models to represent the passive viscoelasticity and active muscle properties is formulated. The model thus formulated is optimised using genetic optimization, and validated against experimental data. The developed model can be used for simulation of joint movements as well as for control development. The results show that the model developed gives an accurate dynamic characterisation of the knee joint.

  18. Three-dimensional CT angiography study on the relations between the vertebral artery and atlantoaxial joint

    Institute of Scientific and Technical Information of China (English)

    DUAN Shao-yin; LU Shao-mao; YE Feng; LIN Qing-chi; CHEN Liao-bin

    2009-01-01

    Background The vertebral artery (VA) and atlantoaxial joint (AAJ), with complicated structures, are located in the depths of the head-neck boundary area, the regional anatomy of which cannot be shown globally and directly. This study aims to evaluate three-dimensional CT angiography (3DCTA) in displaying the AAJ, atlantoaxial segment of the vertebral artery (ASVA) and the identification of their interrelations.Methods Sixty-eight subjects without pathology of the ASVA and AAJ were selected from head-neck CTA examination. All the 3D images were formed with volume rendering (VR) together with techniques of separating, fusing, opacifying and false-coloring (SFOF). On the 3D images, the ASVA and AAJ were observed, and their interrelations were measured.Results All the 3DCTA images were of high quality and up to our requirements. They could cleady and directly show the ASVA, ascending along the AAJ. There were 5 curves in the course of the ASVA, of which 2 curves were away from the atlantoaxial joint, one in the 2nd curve of 0.0 mm-5.4 mm, the other in the 4th of 2.6 mm-9.2 mm. There was no significant difference in the measurements between left and dght (P>0.05). The curved parts of the ASVA slightly expanded, with the biggest diameter of 5.6 mm in the 4th curve. Statistical comparison shows that the left ASVA is larger than the right (P<0.05). Variations of the ASVA were found in 8 cases and of the AAJ in 12.Conclusions 3DCTA can globally and directly demonstrate the structures of the AAJ, ASVA and their interrelations. The 3D imaging data make up and enrich the research contents of regional anatomy and lay the foundation for related study and applications.

  19. Semi-automatic knee cartilage segmentation

    Science.gov (United States)

    Dam, Erik B.; Folkesson, Jenny; Pettersen, Paola C.; Christiansen, Claus

    2006-03-01

    Osteo-Arthritis (OA) is a very common age-related cause of pain and reduced range of motion. A central effect of OA is wear-down of the articular cartilage that otherwise ensures smooth joint motion. Quantification of the cartilage breakdown is central in monitoring disease progression and therefore cartilage segmentation is required. Recent advances allow automatic cartilage segmentation with high accuracy in most cases. However, the automatic methods still fail in some problematic cases. For clinical studies, even if a few failing cases will be averaged out in the overall results, this reduces the mean accuracy and precision and thereby necessitates larger/longer studies. Since the severe OA cases are often most problematic for the automatic methods, there is even a risk that the quantification will introduce a bias in the results. Therefore, interactive inspection and correction of these problematic cases is desirable. For diagnosis on individuals, this is even more crucial since the diagnosis will otherwise simply fail. We introduce and evaluate a semi-automatic cartilage segmentation method combining an automatic pre-segmentation with an interactive step that allows inspection and correction. The automatic step consists of voxel classification based on supervised learning. The interactive step combines a watershed transformation of the original scan with the posterior probability map from the classification step at sub-voxel precision. We evaluate the method for the task of segmenting the tibial cartilage sheet from low-field magnetic resonance imaging (MRI) of knees. The evaluation shows that the combined method allows accurate and highly reproducible correction of the segmentation of even the worst cases in approximately ten minutes of interaction.

  20. Classification of fused face images using multilayer perceptron neural network

    CERN Document Server

    Bhattacharjee, Debotosh; Nasipuri, Mita; Basu, Dipak Kumar; Kundu, Mahantapas

    2010-01-01

    This paper presents a concept of image pixel fusion of visual and thermal faces, which can significantly improve the overall performance of a face recognition system. Several factors affect face recognition performance including pose variations, facial expression changes, occlusions, and most importantly illumination changes. So, image pixel fusion of thermal and visual images is a solution to overcome the drawbacks present in the individual thermal and visual face images. Fused images are projected into eigenspace and finally classified using a multi-layer perceptron. In the experiments we have used Object Tracking and Classification Beyond Visible Spectrum (OTCBVS) database benchmark thermal and visual face images. Experimental results show that the proposed approach significantly improves the verification and identification performance and the success rate is 95.07%. The main objective of employing fusion is to produce a fused image that provides the most detailed and reliable information. Fusion of multip...

  1. Reliability assessment of reserved water disposal with erodible fuse plug

    Directory of Open Access Journals (Sweden)

    Kosichenko Yuriy Mikhaylovich

    Full Text Available Water disposal constructions are one of the most responsible constructions of reservoir hydrosystem, that’s why the a lot of attention was always paid to the problems of estimating and providing their reliability and safety. The most important function of such objects is providing reliability and safety of other hydraulic constructions and economic assets in afterbay and water head. The authors offer estimation method for reliability and faultless performance of reserved water disposal with erodible fuse plug on low-head water development. In order to estimate the reliability of reserved water disposal with erodible fuse plug the Bayesian treatment was used. The calculation of diagnoses (states of reserved water disposal isoffered in case of diagnostic properties k 1 and k 2. One of the main demands placed onreserved water disposals is erosion of soil plug in case of flood discharge exeedance over the estimated frequency with the full opening of the waste sluice.

  2. Segmentation of multiple knee bones from CT for orthopedic knee surgery planning.

    Science.gov (United States)

    Wu, Dijia; Sofka, Michal; Birkbeck, Neil; Zhou, S Kevin

    2014-01-01

    Patient-specific orthopedic knee surgery planning requires precisely segmenting from 3D CT images multiple knee bones, namely femur, tibia, fibula, and patella, around the knee joint with severe pathologies. In this work, we propose a fully automated, highly precise, and computationally efficient segmentation approach for multiple bones. First, each bone is initially segmented using a model-based marginal space learning framework for pose estimation followed by non-rigid boundary deformation. To recover shape details, we then refine the bone segmentation using graph cut that incorporates the shape priors derived from the initial segmentation. Finally we remove overlap between neighboring bones using multi-layer graph partition. In experiments, we achieve simultaneous segmentation of femur, tibia, patella, and fibula with an overall accuracy of less than 1mm surface-to-surface error in less than 90s on hundreds of 3D CT scans with pathological knee joints.

  3. Types of subtalar joint facets.

    Science.gov (United States)

    Jung, Min-Ho; Choi, Byoung Young; Lee, Ji Yong; Han, Chang Sung; Lee, Jin Suk; Yang, Young Chul; Cho, Byung Pil

    2015-08-01

    Articular facets of the clinical subtalar joint (CSTJ) were analyzed using a total of 118 (right 57, left 61) dry, paired calcanei and tali from 68 Korean adult cadavers. The CSTJ facets were classified into the following three types depending on their continuity: type A, all three facets are separated; type B, the anterior and middle facets are partially connected; and type C, the anterior and middle facets are fused to form a single facet. The continuity between the anterior and middle facets was represented by the degree of separation (DS), which ranged between 2.00 (type A) and 1.00 (type C). Type A was most common (39.0 %) in calcanei and rarest (11.0 %) in tali. Matching of calcaneus-talus pairs yielded five combined types: A-A (11.0 %), A-B (28.0 %), B-B (18.6 %), B-C (13.6 %), and C-C (28.8 %). The mean DS was slightly greater in calcanei (1.53) than in tali (1.32), and decreased in the order of types A-A, A-B, B-B, B-C, and C-C. The intersecting angles between the anterior and middle facets, which are related to the mobility of the CSTJ, were inversely related to the DS. These findings indicate that the anterior and middle facets are fused more frequently in tali than in calcanei, and combinations of different CSTJ facet types (A-B, B-C) exist over 40 % of feet. Our results indicate that types with a smaller DS (such as B-C and C-C) are relatively mobile but less stable compared to those with a greater DS (such as A-A and A-B).

  4. Investigate of Mechanical Fuse in Cardan Shaft Using FEM

    OpenAIRE

    Sayed Poorya Rabiei; Reza Azarafza

    2014-01-01

    A Cardan shaft is a mechanical component for transmitting torque and rotation, usually used to connect drive shaft to driven shaft that cannot be connected directly because of distance or the need to allow for relative movement between them. If overload is applied to cardan shaft, failure can occur in each part of the cardan shaft and maybe some irreparable damage occur to the cardan shaft. Thus it is important to investigate the existence of mechanical fuse in cardan shaft, and this subjcet ...

  5. Fused silica suspension for the VIRGO optics: status and perspectives

    CERN Document Server

    Amico, P; Carbone, L; Gammaitoni, L; Punturo, M; Travasso, F; Vocca, H

    2002-01-01

    Thermal noise in mirror suspension wires is the main limitation of low-frequency sensitivity of interferometric gravitational wave detectors. In order to minimize the pendulum thermal noise, a monolithic design, using a low dissipation material, is proposed for VIRGO. High mechanical Qs and high breaking strengths have been obtained for monolithic fused silica fibres. A low-dissipation and high-strength bonding technique using potassium silicate bonding is proposed.

  6. HEp-2 Cell Classification via Fusing Texture and Shape Information

    OpenAIRE

    Qi, Xianbiao; Zhao, Guoying; Li, Chun-Guang; Guo, Jun; Pietikäinen, Matti

    2015-01-01

    Indirect Immunofluorescence (IIF) HEp-2 cell image is an effective evidence for diagnosis of autoimmune diseases. Recently computer-aided diagnosis of autoimmune diseases by IIF HEp-2 cell classification has attracted great attention. However the HEp-2 cell classification task is quite challenging due to large intra-class variation and small between-class variation. In this paper we propose an effective and efficient approach for the automatic classification of IIF HEp-2 cell image by fusing ...

  7. Fusing Laser and Radar Data for Enhanced Situation Awareness

    OpenAIRE

    Eliasson, Emanuel

    2010-01-01

    With an increasing traffic intensity the demands on vehicular safety is higher than ever before. Active safety systems that have been developed recent years are a response to that. In this master thesis Sensor Fusion is used to combine information from a laser scanner and a microwave radar in order to get more information about the surroundings in front of a vehicle. The Extended Kalman Filter method has been used to fuse the information from the sensors. The process model consists partly of ...

  8. Non-invasive management of fused upper incisors

    OpenAIRE

    Pouran Samimi; Mohammad-Reza Shirban; Farahnaz Arbabzadeh-Zavareh

    2012-01-01

    The union of two different dental sprouts which can happen in any phase of dental development is commonly called fusion. This developmental anomaly may cause clinical problems including esthetic impairment, which are mainly treated by endodontic and surgical treatments. There are a few reports of conservative not invasive treatment of fused incisors teeth through restorative or prosthetic techniques. They are rarely reported in mandibular posterior teeth. This paper presents an unusual case o...

  9. Tetrakis(4-tert-butylphenyl) substituted and fused quinoidal porphyrins

    KAUST Repository

    Zeng, Wangdong

    2012-01-01

    4-tert-Butylphenyl-substituted and fused quinoidal porphyrins 1 and 2 are prepared for the first time. They show (1) intense one-photon absorption in the far-red/near-infrared region, (2) enhanced two-photon absorption compared with aromatic porphyrin monomers, and (3) amphoteric redox behavior. Their geometry and electronic structure are studied by DFT calculations. This journal is © 2012 The Royal Society of Chemistry.

  10. Interpolation of segment Euler angles can provide a robust estimation of segment angular trajectories during asymmetric lifting tasks.

    Science.gov (United States)

    Xu, Xu; Chang, Chien-Chi; Faber, Gert S; Kingma, Idsart; Dennerlein, Jack T

    2010-07-20

    Video-based field methods that estimate L5/S1 net joint moments from kinematics based on interpolation in the sagittal plane of joint angles alone can introduce a significant error on the interpolated joint angular trajectory when applied to asymmetric dynamic lifts. Our goal was to evaluate interpolation of segment Euler angles for a wide range of dynamic asymmetric lifting tasks using cubic spline methods by comparing the interpolated values with the continuous measured ones. For most body segments, the estimated trajectories of segment Euler angles have less than 5 degrees RMSE (in each dimension) with 5-point cubic spline interpolation when there is no measurement error of interpolation points. Sensitivity analysis indicates that when the measurement error exists, the root mean square error (RMSE) of estimated trajectories increases. Comparison among different lifting conditions showed that lifting a load from a high initial position yielded a smaller RMSE than lifting from a low initial position. In conclusion, interpolation of segment Euler angles can provide a robust estimation of segment angular trajectories during asymmetric lifting when measurement error of interpolation points can be controlled at a low level.

  11. Influence of System Parameters on Fuse Protection Use in Regenerative DC Drives

    Directory of Open Access Journals (Sweden)

    Isa Salman Qamber

    2009-06-01

    Full Text Available Current limiting fuses are widely used to protect the thyristors in DC drive systems. One very important problem is the choice of the correct voltage rating for fuses protecting regenerative DC drives, where many types of fault may occur, which makes fuse protection difficult. In the event of a commutation failure while regenerating, the fuses need to interrupt the loop supplied by the AC and DC voltages acting in series, which is the most difficult case for protection by fuses. In this paper a detailed study of the complete interruption process has been investigated by modeling of arcing process of the fuse protection against the regenerative circuit internal commutation fault. The effect of varying the motor time constant, supply impedance, number of fuses used to clear the fault and DC machine rating on the total transient response is studied. The model of a 200 A fuse is employed in this study. Fuses in series with both the semiconductor devices (F1 and fuses in AC lines (F2 are considered. Comparison was made between arc energy produced for fuses protecting the regenerative circuit if failure occurs, with the arc energy produced in a standard AC test in order to investigate the required voltage rating for the fuse.

  12. 一期后路保留部分关节突开窗病灶清除短节段椎弓根螺钉内固定治疗腰骶椎结核%ONE-STAGE POSTERIOR RETAINING PART FACET JOINT IN LAMINECTOMY AND DEBRIDEMENT COMBINED WITH SHORT SEGMENTAL PEDICLE SCREW FIXATION FOR LUMBOSACRAL SPINAL TUBERCULOSIS

    Institute of Scientific and Technical Information of China (English)

    陈林; 覃建朴; 敖俊; 廖文波; 蔡玉强

    2016-01-01

    effectiveness of one-stage posterior retaining part facet joint in laminectomy,bone graft and debridement combined with short segmental pedicle screw fixation for lumbosacral spinal tuberculosis.Methods Between January 2010 and December 2014,32 cases of lumbosacral spinal tuberculosis (L4-S1) were treated by one-stage posterior retaining part facet joint in laminectomy,bone graft and debridement combined with short segmental pedicle screw fixation.There were 20 males and 12 females,aged 17-62 years (mean,43 years).The disease duration was 12-48 months (mean,18 months).The involved segments included L5,S1 level in 19 cases and L4.5 level in 13 cases.The effectiveness was evaluated by Oswestry disability index (ODI) and imaging parameters (lumbarsacral angle correction and Bridwel1 classification and CT fusion criteria) after operation.Results The operation was successfully completed in all patients;the average operation time was 180 minutes,and the average intraoperative blood loss was 400 mL.All cases were followed up 12 to 67 months (mean,15.6 months).At last follow-up,common toxic symptom of tuberculosis disappeared,and no internal fixation failure occurred.Neurological function was recovered to normal in 7 patients with neurological symptoms,and American Spinal Injury Association (ASIA) scale was improved to grade E from grade C (2 cases) and grade D (5 cases) before operation.At 1 year and last follow-up,the ODI scores were significantly improved when compared with preoperative score (P<0.05),but no significant difference was found between at 1 year and last follow-up (P>0.05).The lumbarsacral angle was significantly increased at 7 days,1 year and last follow-up when compared with preoperative one (P<0.05),but there was no significant difference between different time points after operation (P>0.05).The bone graft fusion time was 9-24 months (mean,12 months).At 1 year after operation and last follow-up,X-ray Bridwill bone fusion rates were 87.50% (28/32) and 93

  13. MRI characterization of the glenohumeral joint in Apert syndrome

    Energy Technology Data Exchange (ETDEWEB)

    McHugh, Tami [University of Illinois-Chicago, Department of Radiology, Chicago, IL (United States); Wyers, Mary [Children' s Memorial Hospital, Department of Medical Imaging, Children' s Plaza, Box 9, Chicago, IL (United States); King, Erik [Children' s Memorial Hospital, Orthopaedic Surgery, Chicago, IL (United States)

    2007-06-15

    The features of craniosynostosis, facial dysmorphism, and distal extremity syndactyly in Apert syndrome are well known. However, there have been limited descriptions of the associated glenohumeral joint findings. We report the radiographic and MRI abnormalities of the glenohumeral joints in a 10-month-old girl with Apert syndrome. The MRI findings in the girl support the hypothesis that the pathogenesis of Apert syndrome is caused by defective cartilage segmentation with premature and abnormal ossification of a cartilage bar within a joint space. The resultant shoulder joint deformity is related to glenoid hypoplasia and growth arrest of the medial aspect of the humeral head. (orig.)

  14. Study of Fragmentation Process of Fused Fluxes Using Air

    Directory of Open Access Journals (Sweden)

    Daniel Pérez Pérez

    2011-06-01

    Full Text Available In the paper the fragmentation process with air of fused fluxes is studied by means of a particular treatment of the interaction process between the air and flux fluids starting from physical and mathematical considerations of the collision phenomenon which are the result of the application of Newton's mechanics-classical theory. In the paper is schematized the impact and change of trajectory process of the incandescent fused flux flow because of the air mechanical action provided by a blowpipe and the equations referred to the interaction between the fluids are set. As a result, the equations for estimating the exit angle and the average velocities of the pellets formed are determined whenever the interacting air and flux fluxes are known as well as the incidence angles. From the theory developed the essential parameters of the granulation process with air of fused fluxes, by considering the average diameter of the particles to be obtained for their industrial performance can be estimated.

  15. Sampled MTF of fused fiber optic components and bonded assemblies

    Science.gov (United States)

    Carter, Thomas

    2013-05-01

    Fused fiber optic devices are bundles of glass optical fibers that have been successively bundled and drawn to smaller and smaller sizes, effectively creating a "zero optical path window". Due to the nature of fiber's clad and core design, pixelization or sampling of the resulting image occurs; this sampling fundamentally degrades the image. Degradation of a resulting image caused by an optical system can be quantified by way of its Modulation Transfer Function. However, since fused fiber optic devices first sample then effectively project the original image, they do not meet the Fourier transform's prerequisite conditions of being linear and isoplanatic. Current technologies at SCHOTT Lighting and Imaging have initiated a study to determine methodology for measuring the sampled modulation transfer function of bonded assemblies such as bonded Faceplate-to-OLED and Faceplate-tosensor assemblies. The use of randomly generated targets imaged through the bonded assemblies proved to be a useful tactic. This paper discusses the test methods developed and subsequent measurement of the sampled modulation transfer function of fused fiber optic bundles and bonded assemblies.

  16. Production of chicken chimeras by fusing blastodermal cells with electroporation

    Institute of Scientific and Technical Information of China (English)

    S.Aritomi; N.Fujihara

    2000-01-01

    Aim: To establish techniques for producing somatic and gennline chimeric chicken by transferring blastodennal cells fused with electroporation. Methods: Stage-X blastodermal cells isolated from freshly laid fertile unincubated white Leghom and Rhode Island red chicken eggs were fused with electroporation. The treated cell suspension was transferred to the recovery medium (DMEM containing 10% FBS) and was injected into the subgerminal cavity of recipient tmincubated embryos (stage X). Results: Of 177 recipient embryos injected with the fusing blastodermal cells, 6 (3.4%) survived to hatching. Somatic chimerism was examined in the melanocyte of the feather. The presence of feathers originating from the donor cell was observed in 1 bird (16.7%) out of the 6 hatched birds. After 21 days of incubation two birds out of five embryos were subjected to polymemse chain reaction (PCR) analysis for W-chromosome-specific DNA for each tissue. One bird possessed W-chromosome-specific DNA in the stomach, and the other exhibited the same DNA in the left and right gonads and other tissues, but not the stomach. Conclusion: Recipient embryo having electrofused blastodermal cells yields somatic and germline chimeric chickens more successfully.(Asian J Androl 2000 Dec;2:271-275)

  17. Fluid of fused spheres as a model for protein solution

    Directory of Open Access Journals (Sweden)

    M. Kastelic

    2016-03-01

    Full Text Available In this work we examine thermodynamics of fluid with "molecules" represented by two fused hard spheres, decorated by the attractive square-well sites. Interactions between these sites are of short-range and cause association between the fused-sphere particles. The model can be used to study the non-spherical (or dimerized proteins in solution. Thermodynamic quantities of the system are calculated using a modification of Wertheim's thermodynamic perturbation theory and the results compared with new Monte Carlo simulations under isobaric-isothermal conditions. In particular, we are interested in the liquid-liquid phase separation in such systems. The model fluid serves to evaluate the effect of the shape of the molecules, changing from spherical to more elongated (two fused spheres ones. The results indicate that the effect of the non-spherical shape is to reduce the critical density and temperature. This finding is consistent with experimental observations for the antibodies of non-spherical shape.

  18. Rediscovering market segmentation.

    Science.gov (United States)

    Yankelovich, Daniel; Meer, David

    2006-02-01

    In 1964, Daniel Yankelovich introduced in the pages of HBR the concept of nondemographic segmentation, by which he meant the classification of consumers according to criteria other than age, residence, income, and such. The predictive power of marketing studies based on demographics was no longer strong enough to serve as a basis for marketing strategy, he argued. Buying patterns had become far better guides to consumers' future purchases. In addition, properly constructed nondemographic segmentations could help companies determine which products to develop, which distribution channels to sell them in, how much to charge for them, and how to advertise them. But more than 40 years later, nondemographic segmentation has become just as unenlightening as demographic segmentation had been. Today, the technique is used almost exclusively to fulfill the needs of advertising, which it serves mainly by populating commercials with characters that viewers can identify with. It is true that psychographic types like "High-Tech Harry" and "Joe Six-Pack" may capture some truth about real people's lifestyles, attitudes, self-image, and aspirations. But they are no better than demographics at predicting purchase behavior. Thus they give corporate decision makers very little idea of how to keep customers or capture new ones. Now, Daniel Yankelovich returns to these pages, with consultant David Meer, to argue the case for a broad view of nondemographic segmentation. They describe the elements of a smart segmentation strategy, explaining how segmentations meant to strengthen brand identity differ from those capable of telling a company which markets it should enter and what goods to make. And they introduce their "gravity of decision spectrum", a tool that focuses on the form of consumer behavior that should be of the greatest interest to marketers--the importance that consumers place on a product or product category.

  19. Segmentation of Color Images Based on Different Segmentation Techniques

    Directory of Open Access Journals (Sweden)

    Purnashti Bhosale

    2013-03-01

    Full Text Available In this paper, we propose an Color image segmentation algorithm based on different segmentation techniques. We recognize the background objects such as the sky, ground, and trees etc based on the color and texture information using various methods of segmentation. The study of segmentation techniques by using different threshold methods such as global and local techniques and they are compared with one another so as to choose the best technique for threshold segmentation. Further segmentation is done by using clustering method and Graph cut method to improve the results of segmentation.

  20. High-performance fused indium gallium arsenide/silicon photodiode

    Science.gov (United States)

    Kang, Yimin

    Modern long haul, high bit rate fiber-optic communication systems demand photodetectors with high sensitivity. Avalanche photodiodes (APDs) exhibit superior sensitivity performance than other types of photodetectors by virtual of its internal gain mechanism. This dissertation work further advances the APD performance by applying a novel materials integration technique. It is the first successful demonstration of wafer fused InGaAs/Si APDs with low dark current and low noise. APDs generally adopt separate absorption and multiplication (SAM) structure, which allows independent optimization of materials properties in two distinct regions. While the absorption material needs to have high absorption coefficient in the target wavelength range to achieve high quantum efficiency, it is desirable for the multiplication material to have large discrepancy between its electron and hole ionization coefficients to reduce noise. According to these criteria, InGaAs and Si are the ideal materials combination. Wafer fusion is the enabling technique that makes this theoretical ideal an experimental possibility. APDs fabricated on the fused InGaAs/Si wafer with mesa structure exhibit low dark current and low noise. Special device fabrication techniques and high quality wafer fusion reduce dark current to nano ampere level at unity gain, comparable to state-of-the-art commercial III/V APDs. The small excess noise is attributed to the large difference in ionization coefficients between electrons and holes in silicon. Detailed layer structure designs are developed specifically for fused InGaAs/Si APDs based on principles similar to those used in traditional InGaAs/InP APDs. An accurate yet straightforward technique for device structural parameters extraction is also proposed. The extracted results from the fabricated APDs agree with device design parameters. This agreement also confirms that the fusion interface has negligible effect on electric field distributions for devices fabricated

  1. Segmented conjugated polymers

    Indian Academy of Sciences (India)

    G Padmanaban; S Ramakrishnan

    2003-08-01

    Segmented conjugated polymers, wherein the conjugation is randomly truncated by varying lengths of non-conjugated segments, form an interesting class of polymers as they not only represent systems of varying stiffness, but also ones where the backbone can be construed as being made up of chromophores of varying excitation energies. The latter feature, especially when the chromophores are fluorescent, like in MEHPPV, makes these systems particularly interesting from the photophysics point of view. Segmented MEHPPV- samples, where x represents the mole fraction of conjugated segments, were prepared by a novel approach that utilizes a suitable precursor wherein selective elimination of one of the two eliminatable groups is affected; the uneliminated units serve as conjugation truncations. Control of the composition x of the precursor therefore permits one to prepare segmented MEHPPV- samples with varying levels of conjugation (elimination). Using fluorescence spectroscopy, we have seen that even in single isolated polymer chains, energy migration from the shorter (higher energy) chromophores to longer (lower energy) ones occurs – the extent of which depends on the level of conjugation. Further, by varying the solvent composition, it is seen that the extent of energy transfer and the formation of poorly emissive inter-chromophore excitons are greatly enhanced with increasing amounts of non-solvent. A typical S-shaped curve represents the variation of emission yields as a function of composition suggestive of a cooperative collapse of the polymer coil, reminiscent of conformational transitions seen in biological macromolecules.

  2. Scorpion image segmentation system

    Science.gov (United States)

    Joseph, E.; Aibinu, A. M.; Sadiq, B. A.; Bello Salau, H.; Salami, M. J. E.

    2013-12-01

    Death as a result of scorpion sting has been a major public health problem in developing countries. Despite the high rate of death as a result of scorpion sting, little report exists in literature of intelligent device and system for automatic detection of scorpion. This paper proposed a digital image processing approach based on the floresencing characteristics of Scorpion under Ultra-violet (UV) light for automatic detection and identification of scorpion. The acquired UV-based images undergo pre-processing to equalize uneven illumination and colour space channel separation. The extracted channels are then segmented into two non-overlapping classes. It has been observed that simple thresholding of the green channel of the acquired RGB UV-based image is sufficient for segmenting Scorpion from other background components in the acquired image. Two approaches to image segmentation have also been proposed in this work, namely, the simple average segmentation technique and K-means image segmentation. The proposed algorithm has been tested on over 40 UV scorpion images obtained from different part of the world and results obtained show an average accuracy of 97.7% in correctly classifying the pixel into two non-overlapping clusters. The proposed 1system will eliminate the problem associated with some of the existing manual approaches presently in use for scorpion detection.

  3. Globographic visualisation of three dimensional joint angles.

    Science.gov (United States)

    Baker, Richard

    2011-07-07

    Three different methods for describing three dimensional joint angles are commonly used in biomechanics. The joint coordinate system and Cardan/Euler angles are conceptually quite different but are known to represent the same underlying mathematics. More recently the globographic method has been suggested as an alternative and this has proved particularly attractive for the shoulder joint. All three methods can be implemented in a number of ways leading to a choice of angle definitions. Very recently Rab has demonstrated that the globographic method is equivalent to one implementation of the joint coordinate system. This paper presents a rigorous analysis of the three different methods and proves their mathematical equivalence. The well known sequence dependence of Cardan/Euler is presented as equivalent to configuration dependence of the joint coordinate system and orientation dependence of globographic angles. The precise definition of different angle sets can be easily visualised using the globographic method using analogues of longitude, latitude and surface bearings with which most users will already be familiar. The method implicitly requires one axis of the moving segment to be identified as its principal axis and this can be extremely useful in helping define the most appropriate angle set to describe the orientation of any particular joint. Using this technique different angle sets are considered to be most appropriate for different joints and examples of this for the hip, knee, ankle, pelvis and axial skeleton are outlined.

  4. Sealed joint structure for electrochemical device

    Science.gov (United States)

    Tucker, Michael C; Jacobson, Craig P; De Jonghe, Lutgard C; Visco, Steven J

    2013-05-21

    Several members make up a joint in a high-temperature electrochemical device, wherein the various members perform different functions. The joint is useful for joining multiple cells (generally tubular modules) of an electrochemical device to produce a multi-cell segment-in-series stack for a solid oxide fuel cell, for instance. The joint includes sections that bond the joining members to each other; one or more seal sections that provide gas-tightness, and sections providing electrical connection and/or electrical insulation between the various joining members. A suitable joint configuration for an electrochemical device has a metal joint housing, a first porous electrode, a second porous electrode, separated from the first porous electrode by a solid electrolyte, and an insulating member disposed between the metal joint housing and the electrolyte and second electrode. One or more brazes structurally and electrically connects the first electrode to the metal joint housing and forms a gas tight seal between the first electrode and the second electrode.

  5. Segmented heterochromia in scalp hair.

    Science.gov (United States)

    Yoon, Kyeong Han; Kim, Daehwan; Sohn, Seonghyang; Lee, Won Soo

    2003-12-01

    Segmented heterochromia of scalp hair is characterized by the irregularly alternating segmentation of hair into dark and light bands and is known to be associated with iron deficiency anemia. The authors report the case of an 11-year-old boy with segmented heterochromia associated with iron deficiency anemia. After 11 months of iron replacement, the boy's segmented heterochromic hair recovered completely.

  6. Multi-scale classification based lesion segmentation for dermoscopic images.

    Science.gov (United States)

    Abedini, Mani; Codella, Noel; Chakravorty, Rajib; Garnavi, Rahil; Gutman, David; Helba, Brian; Smith, John R

    2016-08-01

    This paper presents a robust segmentation method based on multi-scale classification to identify the lesion boundary in dermoscopic images. Our proposed method leverages a collection of classifiers which are trained at various resolutions to categorize each pixel as "lesion" or "surrounding skin". In detection phase, trained classifiers are applied on new images. The classifier outputs are fused at pixel level to build probability maps which represent lesion saliency maps. In the next step, Otsu thresholding is applied to convert the saliency maps to binary masks, which determine the border of the lesions. We compared our proposed method with existing lesion segmentation methods proposed in the literature using two dermoscopy data sets (International Skin Imaging Collaboration and Pedro Hispano Hospital) which demonstrates the superiority of our method with Dice Coefficient of 0.91 and accuracy of 94%.

  7. A Design of Penetration Ammunition Fuse System Based on Embedded Technology

    Institute of Scientific and Technical Information of China (English)

    LI Qiang; LIU Xiao-ming; XIE Xiao-mei

    2007-01-01

    The hard target smart fuse of penetration ammunition is developing to be smaller,lighter, smarter and multifunction. After analyzing the characteristics of high-g accelerating signals and the penetration algorithms, this paper provides a solution of penetration ammunition fuse system based on embedded technology. This fuse system realizes acquisition of the high-g accelerating signals and uses the appropriate penetration algorithms to process them. The fuse system can not only make the same type of penetration ammunition to attack different kinds of objects accurately, but also meet the other requirements of the function of penetration ammunition fuse system.

  8. Optimally segmented magnetic structures

    DEFF Research Database (Denmark)

    Insinga, Andrea Roberto; Bahl, Christian; Bjørk, Rasmus;

    ], or are applicable only to analytically solvable geometries[4]. In addition, some questions remained fundamentally unanswered, such as how to segment a given design into N uniformly magnetized pieces.Our method calculates the globally optimal shape and magnetization direction of each segment inside a certain......We present a semi-analytical algorithm for magnet design problems, which calculates the optimal way to subdivide a given design region into uniformly magnetized segments.The availability of powerful rare-earth magnetic materials such as Nd-Fe-B has broadened the range of applications of permanent...... designarea with an optional constraint on the total amount of magnetic material. The method can be applied to any objective functional which is linear respect to the field, and with any combination of linear materials. Being based on an analytical-optimization approach, the algorithm is not computationally...

  9. Segmentation of complex document

    Directory of Open Access Journals (Sweden)

    Souad Oudjemia

    2014-06-01

    Full Text Available In this paper we present a method for segmentation of documents image with complex structure. This technique based on GLCM (Grey Level Co-occurrence Matrix used to segment this type of document in three regions namely, 'graphics', 'background' and 'text'. Very briefly, this method is to divide the document image, in block size chosen after a series of tests and then applying the co-occurrence matrix to each block in order to extract five textural parameters which are energy, entropy, the sum entropy, difference entropy and standard deviation. These parameters are then used to classify the image into three regions using the k-means algorithm; the last step of segmentation is obtained by grouping connected pixels. Two performance measurements are performed for both graphics and text zones; we have obtained a classification rate of 98.3% and a Misclassification rate of 1.79%.

  10. Microscopic Halftone Image Segmentation

    Institute of Scientific and Technical Information of China (English)

    WANG Yong-gang; YANG Jie; DING Yong-sheng

    2004-01-01

    Microscopic halftone image recognition and analysis can provide quantitative evidence for printing quality control and fault diagnosis of printing devices, while halftone image segmentation is one of the significant steps during the procedure. Automatic segmentation on microscopic dots by the aid of the Fuzzy C-Means (FCM) method that takes account of the fuzziness of halftone image and utilizes its color information adequately is realized. Then some examples show the technique effective and simple with better performance of noise immunity than some usual methods. In addition, the segmentation results obtained by the FCM in different color spaces are compared, which indicates that the method using the FCM in the f1f2f3 color space is superior to the rest.

  11. International joint ventures

    DEFF Research Database (Denmark)

    Sørensen, Karsten Engsig

    2001-01-01

    The article analysis problems connected with corporate joint ventures. Among others the possible conflicts between the joint venture agreement and the statutes of the companies is examined, as well as certain problems connected to the fact that the joint venture partners have created commen control...... over their joint company....

  12. GPS Control Segment Improvements

    Science.gov (United States)

    2015-04-29

    Systems Center GPS Control Segment Improvements Mr. Tim McIntyre GPS Product Support Manager GPS Ops Support and Sustainment Division Peterson...DATE 29 APR 2015 2. REPORT TYPE 3. DATES COVERED 00-00-2015 to 00-00-2015 4. TITLE AND SUBTITLE GPS Control Segment Improvements 5a. CONTRACT...ORGANIZATION NAME(S) AND ADDRESS(ES) Air Force Space Command,Space and Missile Systems Center, GPS Ops Support and Sustainment Division,Peterson AFB,CO,80916 8

  13. Statistical Images Segmentation

    Directory of Open Access Journals (Sweden)

    Corina Curilă

    2008-05-01

    Full Text Available This paper deals with fuzzy statistical imagesegmentation. We introduce a new hierarchicalMarkovian fuzzy hidden field model, which extends to thefuzzy case the classical Pérez and Heitz hard model. Twofuzzy statistical segmentation methods related with themodel proposed are defined in this paper and we show viasimulations that they are competitive with, in some casesthan, the classical Maximum Posterior Mode (MPMbased methods. Furthermore, they are faster, which willshould facilitate extensions to more than two hard classesin future work. In addition, the model proposed isapplicable to the multiscale segmentation andmultiresolution images fusion problems.

  14. A label field fusion bayesian model and its penalized maximum rand estimator for image segmentation.

    Science.gov (United States)

    Mignotte, Max

    2010-06-01

    This paper presents a novel segmentation approach based on a Markov random field (MRF) fusion model which aims at combining several segmentation results associated with simpler clustering models in order to achieve a more reliable and accurate segmentation result. The proposed fusion model is derived from the recently introduced probabilistic Rand measure for comparing one segmentation result to one or more manual segmentations of the same image. This non-parametric measure allows us to easily derive an appealing fusion model of label fields, easily expressed as a Gibbs distribution, or as a nonstationary MRF model defined on a complete graph. Concretely, this Gibbs energy model encodes the set of binary constraints, in terms of pairs of pixel labels, provided by each segmentation results to be fused. Combined with a prior distribution, this energy-based Gibbs model also allows for definition of an interesting penalized maximum probabilistic rand estimator with which the fusion of simple, quickly estimated, segmentation results appears as an interesting alternative to complex segmentation models existing in the literature. This fusion framework has been successfully applied on the Berkeley image database. The experiments reported in this paper demonstrate that the proposed method is efficient in terms of visual evaluation and quantitative performance measures and performs well compared to the best existing state-of-the-art segmentation methods recently proposed in the literature.

  15. Reduced field-of-view DTI segmentation of cervical spine tissue.

    Science.gov (United States)

    Tang, Lihua; Wen, Ying; Zhou, Zhenyu; von Deneen, Karen M; Huang, Dehui; Ma, Lin

    2013-11-01

    The number of diffusion tensor imaging (DTI) studies regarding the human spine has considerably increased and it is challenging because of the spine's small size and artifacts associated with the most commonly used clinical imaging method. A novel segmentation method based on the reduced field-of-view (rFOV) DTI dataset is presented in cervical spinal canal cerebrospinal fluid, spinal cord grey matter and white matter classification in both healthy volunteers and patients with neuromyelitis optica (NMO) and multiple sclerosis (MS). Due to each channel based on high resolution rFOV DTI images providing complementary information on spinal tissue segmentation, we want to choose a different contribution map from multiple channel images. Via principal component analysis (PCA) and a hybrid diffusion filter with a continuous switch applied on fourteen channel features, eigen maps can be obtained and used for tissue segmentation based on the Bayesian discrimination method. Relative to segmentation by a pair of expert readers, all of the automated segmentation results in the experiment fall in the good segmentation area and performed well, giving an average segmentation accuracy of about 0.852 for cervical spinal cord grey matter in terms of volume overlap. Furthermore, this has important applications in defining more accurate human spinal cord tissue maps when fusing structural data with diffusion data. rFOV DTI and the proposed automatic segmentation outperform traditional manual segmentation methods in classifying MR cervical spinal images and might be potentially helpful for detecting cervical spine diseases in NMO and MS.

  16. Upper Limb Kinematics Using Inertial and Magnetic Sensors: Comparison of Sensor-to-Segment Calibrations

    Directory of Open Access Journals (Sweden)

    Brice Bouvier

    2015-07-01

    Full Text Available Magneto-Inertial Measurement Unit sensors (MIMU display high potential for the quantitative evaluation of upper limb kinematics, as they allow monitoring ambulatory measurements. The sensor-to-segment calibration step, consisting of establishing the relation between MIMU sensors and human segments, plays an important role in the global accuracy of joint angles. The aim of this study was to compare sensor-to-segment calibrations for the MIMU-based estimation of wrist, elbow, and shoulder joint angles, by examining trueness (“close to the reference” and precision (reproducibility validity criteria. Ten subjects performed five sessions with three different operators. Three classes of calibrations were studied: segment axes equal to technical MIMU axes (TECH, segment axes generated during a static pose (STATIC, and those generated during functional movements (FUNCT. The calibrations were compared during the maximal uniaxial movements of each joint, plus an extra multi-joint movement. Generally, joint angles presented good trueness and very good precision in the range 5°–10°. Only small discrepancy between calibrations was highlighted, with the exception of a few cases. The very good overall accuracy (trueness and precision of MIMU-based joint angle data seems to be more dependent on the level of rigor of the experimental procedure (operator training than on the choice of calibration itself.

  17. Upper Limb Kinematics Using Inertial and Magnetic Sensors: Comparison of Sensor-to-Segment Calibrations.

    Science.gov (United States)

    Bouvier, Brice; Duprey, Sonia; Claudon, Laurent; Dumas, Raphaël; Savescu, Adriana

    2015-07-31

    Magneto-Inertial Measurement Unit sensors (MIMU) display high potential for the quantitative evaluation of upper limb kinematics, as they allow monitoring ambulatory measurements. The sensor-to-segment calibration step, consisting of establishing the relation between MIMU sensors and human segments, plays an important role in the global accuracy of joint angles. The aim of this study was to compare sensor-to-segment calibrations for the MIMU-based estimation of wrist, elbow, and shoulder joint angles, by examining trueness ("close to the reference") and precision (reproducibility) validity criteria. Ten subjects performed five sessions with three different operators. Three classes of calibrations were studied: segment axes equal to technical MIMU axes (TECH), segment axes generated during a static pose (STATIC), and those generated during functional movements (FUNCT). The calibrations were compared during the maximal uniaxial movements of each joint, plus an extra multi-joint movement. Generally, joint angles presented good trueness and very good precision in the range 5°-10°. Only small discrepancy between calibrations was highlighted, with the exception of a few cases. The very good overall accuracy (trueness and precision) of MIMU-based joint angle data seems to be more dependent on the level of rigor of the experimental procedure (operator training) than on the choice of calibration itself.

  18. Failure Characteristics of Joint Bolts in Shield Tunnels Subjected to Impact Loads from a Derailed Train

    Directory of Open Access Journals (Sweden)

    Qixiang Yan

    2017-01-01

    Full Text Available Impact loads generated by derailed trains can be extremely high, especially in the case of heavy trains running at high speeds, which usually cause significant safety issues to the rail infrastructures. In shield tunnels, such impact loads may not only cause the damage and deformation of concrete segments, but also lead to the failure of segmental joint bolts. This paper presents a numerical study on the failure behavior of segmental joint bolts in the shield tunnel under impact loading resulting from train derailments. A three-dimensional (3D numerical model of a shield tunnel based on the finite element (FE modelling strategy was established, in which the structural behavior of the segmental joint surfaces and the mechanical behavior of the segmental joint bolts were determined. The numerical results show that the occurrence of bolt failure starts at the joints near the impacted segment and develops along the travel direction of train. An extensive parametric study was subsequently performed and the influences of the bolt failure on the dynamic response of the segment were investigated. In particular, the proposed FE model and the analytical results will be used for optimizing the design method of the shield tunnel in preventing the failure of the joint bolts due to the impact load from a derailed HST.

  19. Syntheses of fused tetrahydro--carboline analogues through imide carbonyl activation using BBr3: Evidence for the involvement of fused cyclic -acyliminium ion intermediate

    Indian Academy of Sciences (India)

    Selvaraj Mangalaraj; Jayaraman Selvakumar; Chinnasamy Ramaraj Ramanathan

    2015-05-01

    The fused cyclic -acyliminium ion generated during the imide carbonyl activation reaction of phenethylphthalimide was confirmed by single crystal X-ray diffraction. The Lewis acid assisted imide carbonyl activation methodology was successfully extended to synthesize fused tetrahydro--carboline units from the corresponding -indolylethylimides.

  20. Sipunculans and segmentation

    DEFF Research Database (Denmark)

    Wanninger, Andreas; Kristof, Alen; Brinkmann, Nora

    2009-01-01

    Comparative molecular, developmental and morphogenetic analyses show that the three major segmented animal groups- Lophotrochozoa, Ecdysozoa and Vertebrata-use a wide range of ontogenetic pathways to establish metameric body organization. Even in the life history of a single specimen, different m...

  1. [Segmental testicular infarction].

    Science.gov (United States)

    Ripa Saldías, L; Guarch Troyas, R; Hualde Alfaro, A; de Pablo Cárdenas, A; Ruiz Ramo, M; Pinós Paul, M

    2006-02-01

    We report the case of a 47 years old man previously diagnosed of left hidrocele. After having a recent mild left testicular pain, an ultrasonografic study revealed a solid hipoecoic testicular lesion rounded by a big hidrocele, suggesting a testicular neoplasm. Radical inguinal orchiectomy was made and pathologic study showed segmental testicular infarction. No malignancy was found. We review the literature of the topic.

  2. Dictionary Based Image Segmentation

    DEFF Research Database (Denmark)

    Dahl, Anders Bjorholm; Dahl, Vedrana Andersen

    2015-01-01

    We propose a method for weakly supervised segmentation of natural images, which may contain both textured or non-textured regions. Our texture representation is based on a dictionary of image patches. To divide an image into separated regions with similar texture we use an implicit level sets...

  3. Tree Classification with Fused Mobile Laser Scanning and Hyperspectral Data

    Directory of Open Access Journals (Sweden)

    Juha Hyyppä

    2011-05-01

    Full Text Available Mobile Laser Scanning data were collected simultaneously with hyperspectral data using the Finnish Geodetic Institute Sensei system. The data were tested for tree species classification. The test area was an urban garden in the City of Espoo, Finland. Point clouds representing 168 individual tree specimens of 23 tree species were determined manually. The classification of the trees was done using first only the spatial data from point clouds, then with only the spectral data obtained with a spectrometer, and finally with the combined spatial and hyperspectral data from both sensors. Two classification tests were performed: the separation of coniferous and deciduous trees, and the identification of individual tree species. All determined tree specimens were used in distinguishing coniferous and deciduous trees. A subset of 133 trees and 10 tree species was used in the tree species classification. The best classification results for the fused data were 95.8% for the separation of the coniferous and deciduous classes. The best overall tree species classification succeeded with 83.5% accuracy for the best tested fused data feature combination. The respective results for paired structural features derived from the laser point cloud were 90.5% for the separation of the coniferous and deciduous classes and 65.4% for the species classification. Classification accuracies with paired hyperspectral reflectance value data were 90.5% for the separation of coniferous and deciduous classes and 62.4% for different species. The results are among the first of their kind and they show that mobile collected fused data outperformed single-sensor data in both classification tests and by a significant margin.

  4. A new method based on Dempster-Shafer theory and fuzzy c-means for brain MRI segmentation

    Science.gov (United States)

    Liu, Jie; Lu, Xi; Li, Yunpeng; Chen, Xiaowu; Deng, Yong

    2015-10-01

    In this paper, a new method is proposed to decrease sensitiveness to motion noise and uncertainty in magnetic resonance imaging (MRI) segmentation especially when only one brain image is available. The method is approached with considering spatial neighborhood information by fusing the information of pixels with their neighbors with Dempster-Shafer (DS) theory. The basic probability assignment (BPA) of each single hypothesis is obtained from the membership function of applying fuzzy c-means (FCM) clustering to the gray levels of the MRI. Then multiple hypotheses are generated according to the single hypothesis. Then we update the objective pixel’s BPA by fusing the BPA of the objective pixel and those of its neighbors to get the final result. Some examples in MRI segmentation are demonstrated at the end of the paper, in which our method is compared with some previous methods. The results show that the proposed method is more effective than other methods in motion-blurred MRI segmentation.

  5. Collaborative Filtering Fusing Label Features Based on SDAE

    DEFF Research Database (Denmark)

    Huo, Huan; Liu, Xiufeng; Zheng, Deyuan

    2017-01-01

    problem, auxiliary information such as labels are utilized. Another approach of recommendation system is content-based model which can’t be directly integrated with CF-based model due to its inherent characteristics. Considering that deep learning algorithms are capable of extracting deep latent features......, this paper applies Stack Denoising Auto Encoder (SDAE) to content-based model and proposes LCF(Deep Learning for Collaborative Filtering) algorithm by combing CF-based model which fuses label features. Experiments on real-world data sets show that DLCF can largely overcome the sparsity problem...

  6. Fused Deposition Technique for Continuous Fiber Reinforced Thermoplastic

    Science.gov (United States)

    Bettini, Paolo; Alitta, Gianluca; Sala, Giuseppe; Di Landro, Luca

    2017-02-01

    A simple technique for the production of continuous fiber reinforced thermoplastic by fused deposition modeling, which involves a common 3D printer with quite limited modifications, is presented. An adequate setting of processing parameters and deposition path allows to obtain components with well-enhanced mechanical characteristics compared to conventional 3D printed items. The most relevant problems related to the simultaneous feeding of fibers and polymer are discussed. The properties of obtained aramid fiber reinforced polylactic acid (PLA) in terms of impregnation quality and of mechanical response are measured.

  7. CHANGE DETECTION BY FUSING ADVANTAGES OF THRESHOLD AND CLUSTERING METHODS

    Directory of Open Access Journals (Sweden)

    M. Tan

    2017-09-01

    Full Text Available In change detection (CD of medium-resolution remote sensing images, the threshold and clustering methods are two kinds of the most popular ones. It is found that the threshold method of the expectation maximum (EM algorithm usually generates a CD map including many false alarms but almost detecting all changes, and the fuzzy local information c-means algorithm (FLICM obtains a homogeneous CD map but with some missed detections. Therefore, we aim to design a framework to improve CD results by fusing the advantages of threshold and clustering methods. Experimental results indicate the effectiveness of the proposed method.

  8. Fused Deposition Technique for Continuous Fiber Reinforced Thermoplastic

    Science.gov (United States)

    Bettini, Paolo; Alitta, Gianluca; Sala, Giuseppe; Di Landro, Luca

    2016-12-01

    A simple technique for the production of continuous fiber reinforced thermoplastic by fused deposition modeling, which involves a common 3D printer with quite limited modifications, is presented. An adequate setting of processing parameters and deposition path allows to obtain components with well-enhanced mechanical characteristics compared to conventional 3D printed items. The most relevant problems related to the simultaneous feeding of fibers and polymer are discussed. The properties of obtained aramid fiber reinforced polylactic acid (PLA) in terms of impregnation quality and of mechanical response are measured.

  9. Nanodrilling of fused silica using nanosecond laser radiation

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, P., E-mail: pierre.lorenz@iom-leipzig.de; Zajadacz, J.; Bayer, L.; Ehrhardt, M.; Zimmer, K.

    2015-10-01

    Graphical abstract: - Highlights: • Low-fluence irradiation of 10 nm Mo on SiO{sub 2} results in the formation of Mo droplets. • High-fluence irradiation of droplets results in the formation of holes in the SiO{sub 2}. • The process allows the formation of randomly distributed and periodic holes. • The randomly distributed hole density ρ{sub h} depends on the fluence (ρ{sub h} ≤ 1.3 μm{sup −2}). • The interaction of the laser beam with Mo/SiO{sub 2} was simulated by FEM. - Abstract: The fast laser drilling of dielectric surfaces with hole diameters in the sub-μm range and a high aspect ratio is a challenge for laser methods. In this study, a novel laser structuring method for the production of randomly and periodically distributed holes in a fused silica surface will be presented using a self-assembling process. A fused silica surface was covered with a 10 nm thick magnetron-sputtered molybdenum film. The metal film was irradiated by a KrF excimer laser (wavelength λ = 248 nm, pulse duration Δt{sub p} = 25 ns) with low laser fluences (Φ < 1 J/cm{sup 2}) and the laser-induced heating resulting in a melting of the metal film and finally in a self-assembled formation of randomly distributed metal droplets due to the surface tension of the metal liquid phase using a top hat beam profile. Furthermore, the usage of a periodically modulated laser beam profile allows the fabrication of periodically distributed droplet pattern. The multi-pulse irradiation of the laser-generated metal droplets with higher laser fluences results in a stepwise evaporation of the metal and in a partial evaporation of the fused silica near the metal droplets. Finally, the laser-induced stepwise evaporation process results in a formation of cone-like holes in the fused silica surface where the resultant holes are dependent on the size of the generated metal droplets and on the laser parameters. The “drilling” process allows the fabrication of holes with a depth up to 1

  10. All joint moments significantly contribute to trunk angular acceleration.

    Science.gov (United States)

    Nott, Cameron R; Zajac, Felix E; Neptune, Richard R; Kautz, Steven A

    2010-09-17

    Computationally advanced biomechanical analyses of gait demonstrate the often counter-intuitive roles of joint moments on various aspects of gait such as propulsion, swing initiation, and balance. Each joint moment can produce linear and angular acceleration of all body segments (including those on which the moment does not directly act) due to the dynamic coupling inherent in the interconnected musculoskeletal system. This study presents quantitative relationships between individual joint moments and trunk control with respect to balance during gait to show that the ankle, knee, and hip joint moments all affect the angular acceleration of the trunk. We show that trunk angular acceleration is affected by all joints in the leg with varying degrees of dependence during the gait cycle. Furthermore, it is shown that inter-planar coupling exists and a two-dimensional analysis of trunk balance neglects important out-of-plane joint moments that affect trunk angular acceleration.

  11. Remote Sensing Image Fusion at the Segment Level Using a Spatially-Weighted Approach: Applications for Land Cover Spectral Analysis and Mapping

    Directory of Open Access Journals (Sweden)

    Brian Johnson

    2015-01-01

    Full Text Available Segment-level image fusion involves segmenting a higher spatial resolution (HSR image to derive boundaries of land cover objects, and then extracting additional descriptors of image segments (polygons from a lower spatial resolution (LSR image. In past research, an unweighted segment-level fusion (USF approach, which extracts information from a resampled LSR image, resulted in more accurate land cover classification than the use of HSR imagery alone. However, simply fusing the LSR image with segment polygons may lead to significant errors due to the high level of noise in pixels along the segment boundaries (i.e., pixels containing multiple land cover types. To mitigate this, a spatially-weighted segment-level fusion (SWSF method was proposed for extracting descriptors (mean spectral values of segments from LSR images. SWSF reduces the weights of LSR pixels located on or near segment boundaries to reduce errors in the fusion process. Compared to the USF approach, SWSF extracted more accurate spectral properties of land cover objects when the ratio of the LSR image resolution to the HSR image resolution was greater than 2:1, and SWSF was also shown to increase classification accuracy. SWSF can be used to fuse any type of imagery at the segment level since it is insensitive to spectral differences between the LSR and HSR images (e.g., different spectral ranges of the images or different image acquisition dates.

  12. Influence of secondary treatment with CO2 laser irradiation for mitigation site on fused silica surface

    Science.gov (United States)

    Jiang, Yong; Zhou, Qiang; Qiu, Rong; Gao, Xiang; Wang, Hui-Li; Yao, Cai-Zhen; Wang, Jun-Bo; Zhao, Xin; Liu, Chun-Ming; Xiang, Xia; Zu, Xiao-Tao; Yuan, Xiao-Dong; Miao, Xin-Xiang

    2016-10-01

    The ablation debris and raised rim, as well as residual stress and deep crater will be formed during the mitigation of damage site with a CO2 laser irradiation on fused silica surface, which greatly affects the laser damage resistance of optics. In this study, the experimental study combined with numerical simulation is utilized to investigate the effect of the secondary treatment on a mitigated site by CO2 laser irradiation. The results indicate that the ablation debris and the raised rim can be completely eliminated and the depth of crater can be reduced. Notable results show that the residual stress of the mitigation site after treatment will reduce two-thirds of the original stress. Finally, the elimination and the controlling mechanism of secondary treatment on the debris and raised rim, as well as the reasons for changing the profile and stress are analyzed. The results can provide a reference for the optimization treatment of mitigation sites by CO2 laser secondary treatment. Project supported by the National Natural Science Foundation of China (Grant Nos. 61505170, 61505171, and 51535003), the Joint Fund of the National Natural Science Foundation of China, the Chinese Academy of Engineering Physics (Grant No. U1530109), and the China Postdoctoral Science Foundation (Grant No. 2016M592709).

  13. Two Time Point MS Lesion Segmentation in Brain MRI: An Expectation-Maximization Framework.

    Science.gov (United States)

    Jain, Saurabh; Ribbens, Annemie; Sima, Diana M; Cambron, Melissa; De Keyser, Jacques; Wang, Chenyu; Barnett, Michael H; Van Huffel, Sabine; Maes, Frederik; Smeets, Dirk

    2016-01-01

    Purpose: Lesion volume is a meaningful measure in multiple sclerosis (MS) prognosis. Manual lesion segmentation for computing volume in a single or multiple time points is time consuming and suffers from intra and inter-observer variability. Methods: In this paper, we present MSmetrix-long: a joint expectation-maximization (EM) framework for two time point white matter (WM) lesion segmentation. MSmetrix-long takes as input a 3D T1-weighted and a 3D FLAIR MR image and segments lesions in three steps: (1) cross-sectional lesion segmentation of the two time points; (2) creation of difference image, which is used to model the lesion evolution; (3) a joint EM lesion segmentation framework that uses output of step (1) and step (2) to provide the final lesion segmentation. The accuracy (Dice score) and reproducibility (absolute lesion volume difference) of MSmetrix-long is evaluated using two datasets. Results: On the first dataset, the median Dice score between MSmetrix-long and expert lesion segmentation was 0.63 and the Pearson correlation coefficient (PCC) was equal to 0.96. On the second dataset, the median absolute volume difference was 0.11 ml. Conclusions: MSmetrix-long is accurate and consistent in segmenting MS lesions. Also, MSmetrix-long compares favorably with the publicly available longitudinal MS lesion segmentation algorithm of Lesion Segmentation Toolbox.

  14. SAR and Oblique Aerial Optical Image Fusion for Urban Area Image Segmentation

    Science.gov (United States)

    Fagir, J.; Schubert, A.; Frioud, M.; Henke, D.

    2017-05-01

    The fusion of synthetic aperture radar (SAR) and optical data is a dynamic research area, but image segmentation is rarely treated. While a few studies use low-resolution nadir-view optical images, we approached the segmentation of SAR and optical images acquired from the same airborne platform - leading to an oblique view with high resolution and thus increased complexity. To overcome the geometric differences, we generated a digital surface model (DSM) from adjacent optical images and used it to project both the DSM and SAR data into the optical camera frame, followed by segmentation with each channel. The fused segmentation algorithm was found to out-perform the single-channel version.

  15. A unified framework for cross-modality multi-atlas segmentation of brain MRI

    DEFF Research Database (Denmark)

    Eugenio Iglesias, Juan; Rory Sabuncu, Mert; Van Leemput, Koen

    2013-01-01

    Multi-atlas label fusion is a powerful image segmentation strategy that is becoming increasingly popular in medical imaging. A standard label fusion algorithm relies on independently computed pairwise registrations between individual atlases and the (target) image to be segmented....... These registrations are then used to propagate the atlas labels to the target space and fuse them into a single final segmentation. Such label fusion schemes commonly rely on the similarity between intensity values of the atlases and target scan, which is often problematic in medical imaging - in particular, when...... to segment T1-weighted brain scans and vice versa. Our results clearly demonstrate the accuracy gain due to exploiting within-target intensity consistency and integrating registration into label fusion....

  16. STIFFNESS EQUATION OF FINITE SEGMENT FOR FLEXIBLE BEAM-FORMED STRUCTURAL ELEMENTS

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The finite segment modelling for the flexible beam-formed structural elemens is presented,in which the discretization views of the finite segment method and the difference from the finite element method are introduced. In terms of the nodal model, the joint properties are described easily by the model of the finite segment method,and according to the element properties,the assumption of the small strain is only met in the finite segment method, i. e., the geometric nonlinear deformation of the flexible bodies is allowable.Consequently, the finite segment method is very suited to the flexible multibody structure. The finite segment model is used and the arc differentiation is adopted for the differential beam segments.The stiffness equation is derived by the use of the principle of virtual work. The new modelling method shows its normalization, clear physical and geometric meanings and simple computational process.

  17. Segmentation in Tardigrada and diversification of segmental patterns in Panarthropoda.

    Science.gov (United States)

    Smith, Frank W; Goldstein, Bob

    2016-10-31

    The origin and diversification of segmented metazoan body plans has fascinated biologists for over a century. The superphylum Panarthropoda includes three phyla of segmented animals-Euarthropoda, Onychophora, and Tardigrada. This superphylum includes representatives with relatively simple and representatives with relatively complex segmented body plans. At one extreme of this continuum, euarthropods exhibit an incredible diversity of serially homologous segments. Furthermore, distinct tagmosis patterns are exhibited by different classes of euarthropods. At the other extreme, all tardigrades share a simple segmented body plan that consists of a head and four leg-bearing segments. The modular body plans of panarthropods make them a tractable model for understanding diversification of animal body plans more generally. Here we review results of recent morphological and developmental studies of tardigrade segmentation. These results complement investigations of segmentation processes in other panarthropods and paleontological studies to illuminate the earliest steps in the evolution of panarthropod body plans.

  18. The Multimodal Brain Tumor Image Segmentation Benchmark (BRATS).

    Science.gov (United States)

    Menze, Bjoern H; Jakab, Andras; Bauer, Stefan; Kalpathy-Cramer, Jayashree; Farahani, Keyvan; Kirby, Justin; Burren, Yuliya; Porz, Nicole; Slotboom, Johannes; Wiest, Roland; Lanczi, Levente; Gerstner, Elizabeth; Weber, Marc-André; Arbel, Tal; Avants, Brian B; Ayache, Nicholas; Buendia, Patricia; Collins, D Louis; Cordier, Nicolas; Corso, Jason J; Criminisi, Antonio; Das, Tilak; Delingette, Hervé; Demiralp, Çağatay; Durst, Christopher R; Dojat, Michel; Doyle, Senan; Festa, Joana; Forbes, Florence; Geremia, Ezequiel; Glocker, Ben; Golland, Polina; Guo, Xiaotao; Hamamci, Andac; Iftekharuddin, Khan M; Jena, Raj; John, Nigel M; Konukoglu, Ender; Lashkari, Danial; Mariz, José Antonió; Meier, Raphael; Pereira, Sérgio; Precup, Doina; Price, Stephen J; Raviv, Tammy Riklin; Reza, Syed M S; Ryan, Michael; Sarikaya, Duygu; Schwartz, Lawrence; Shin, Hoo-Chang; Shotton, Jamie; Silva, Carlos A; Sousa, Nuno; Subbanna, Nagesh K; Szekely, Gabor; Taylor, Thomas J; Thomas, Owen M; Tustison, Nicholas J; Unal, Gozde; Vasseur, Flor; Wintermark, Max; Ye, Dong Hye; Zhao, Liang; Zhao, Binsheng; Zikic, Darko; Prastawa, Marcel; Reyes, Mauricio; Van Leemput, Koen

    2015-10-01

    In this paper we report the set-up and results of the Multimodal Brain Tumor Image Segmentation Benchmark (BRATS) organized in conjunction with the MICCAI 2012 and 2013 conferences. Twenty state-of-the-art tumor segmentation algorithms were applied to a set of 65 multi-contrast MR scans of low- and high-grade glioma patients-manually annotated by up to four raters-and to 65 comparable scans generated using tumor image simulation software. Quantitative evaluations revealed considerable disagreement between the human raters in segmenting various tumor sub-regions (Dice scores in the range 74%-85%), illustrating the difficulty of this task. We found that different algorithms worked best for different sub-regions (reaching performance comparable to human inter-rater variability), but that no single algorithm ranked in the top for all sub-regions simultaneously. Fusing several good algorithms using a hierarchical majority vote yielded segmentations that consistently ranked above all individual algorithms, indicating remaining opportunities for further methodological improvements. The BRATS image data and manual annotations continue to be publicly available through an online evaluation system as an ongoing benchmarking resource.

  19. Motion segmentation method for hybrid characteristic on human motion.

    Science.gov (United States)

    Lau, Newman; Wong, Ben; Chow, Daniel

    2009-03-11

    Motion segmentation and analysis are used to improve the process of classification of motion and information gathered on repetitive or periodic characteristic. The classification result is useful for ergonomic and postural safety analysis, since repetitive motion is known to be related to certain musculoskeletal disorders. Past studies mainly focused on motion segmentation on particular motion characteristic with certain prior knowledge on static or periodic property of motion, which narrowed method's applicability. This paper attempts to introduce a method to tackle human joint motion without having prior knowledge. The motion is segmented by a two-pass algorithm. Recursive least square (RLS) is firstly used to estimate possible segments on the input human-motion set. Further, period identification and extra segmentation process are applied to produce meaningful segments. Each of the result segments is modeled by a damped harmonic model, with frequency, amplitude and duration produced as parameters for ergonomic evaluation and other human factor studies such as task safety evaluation and sport analysis. Experiments show that the method can handle periodic, random and mixed characteristics on human motion, which can also be extended to the usage in repetitive motion in workflow and irregular periodic motion like sport movement.

  20. Image Segmentation, Registration, Compression, and Matching

    Science.gov (United States)

    Yadegar, Jacob; Wei, Hai; Yadegar, Joseph; Ray, Nilanjan; Zabuawala, Sakina

    2011-01-01

    A novel computational framework was developed of a 2D affine invariant matching exploiting a parameter space. Named as affine invariant parameter space (AIPS), the technique can be applied to many image-processing and computer-vision problems, including image registration, template matching, and object tracking from image sequence. The AIPS is formed by the parameters in an affine combination of a set of feature points in the image plane. In cases where the entire image can be assumed to have undergone a single affine transformation, the new AIPS match metric and matching framework becomes very effective (compared with the state-of-the-art methods at the time of this reporting). No knowledge about scaling or any other transformation parameters need to be known a priori to apply the AIPS framework. An automated suite of software tools has been created to provide accurate image segmentation (for data cleaning) and high-quality 2D image and 3D surface registration (for fusing multi-resolution terrain, image, and map data). These tools are capable of supporting existing GIS toolkits already in the marketplace, and will also be usable in a stand-alone fashion. The toolkit applies novel algorithmic approaches for image segmentation, feature extraction, and registration of 2D imagery and 3D surface data, which supports first-pass, batched, fully automatic feature extraction (for segmentation), and registration. A hierarchical and adaptive approach is taken for achieving automatic feature extraction, segmentation, and registration. Surface registration is the process of aligning two (or more) data sets to a common coordinate system, during which the transformation between their different coordinate systems is determined. Also developed here are a novel, volumetric surface modeling and compression technique that provide both quality-guaranteed mesh surface approximations and compaction of the model sizes by efficiently coding the geometry and connectivity

  1. A New Measure for Analyzing and Fusing Sequences of Objects.

    Science.gov (United States)

    Goulermas, John Yannis; Kostopoulos, Alexandros; Mu, Tingting

    2016-05-01

    This work is related to the combinatorial data analysis problem of seriation used for data visualization and exploratory analysis. Seriation re-sequences the data, so that more similar samples or objects appear closer together, whereas dissimilar ones are further apart. Despite the large number of current algorithms to realize such re-sequencing, there has not been a systematic way for analyzing the resulting sequences, comparing them, or fusing them to obtain a single unifying one. We propose a new positional proximity measure that evaluates the similarity of two arbitrary sequences based on their agreement on pairwise positional information of the sequenced objects. Furthermore, we present various statistical properties of this measure as well as its normalized version modeled as an instance of the generalized correlation coefficient. Based on this measure, we define a new procedure for consensus seriation that fuses multiple arbitrary sequences based on a quadratic assignment problem formulation and an efficient way of approximating its solution. We also derive theoretical links with other permutation distance functions and present their associated combinatorial optimization forms for consensus tasks. The utility of the proposed contributions is demonstrated through the comparison and fusion of multiple seriation algorithms we have implemented, using many real-world datasets from different application domains.

  2. Planning the FUSE Mission Using the SOVA Algorithm

    Science.gov (United States)

    Lanzi, James; Heatwole, Scott; Ward, Philip R.; Civeit, Thomas; Calvani, Humberto; Kruk, Jeffrey W.; Suchkov, Anatoly

    2011-01-01

    Three documents discuss the Sustainable Objective Valuation and Attainability (SOVA) algorithm and software as used to plan tasks (principally, scientific observations and associated maneuvers) for the Far Ultraviolet Spectroscopic Explorer (FUSE) satellite. SOVA is a means of managing risk in a complex system, based on a concept of computing the expected return value of a candidate ordered set of tasks as a product of pre-assigned task values and assessments of attainability made against qualitatively defined strategic objectives. For the FUSE mission, SOVA autonomously assembles a week-long schedule of target observations and associated maneuvers so as to maximize the expected scientific return value while keeping the satellite stable, managing the angular momentum of spacecraft attitude- control reaction wheels, and striving for other strategic objectives. A six-degree-of-freedom model of the spacecraft is used in simulating the tasks, and the attainability of a task is calculated at each step by use of strategic objectives as defined by use of fuzzy inference systems. SOVA utilizes a variant of a graph-search algorithm known as the A* search algorithm to assemble the tasks into a week-long target schedule, using the expected scientific return value to guide the search.

  3. Ball driven type MEMS SAD for artillery fuse

    Science.gov (United States)

    Seok, Jin Oh; Jeong, Ji-hun; Eom, Junseong; Lee, Seung S.; Lee, Chun Jae; Ryu, Sung Moon; Oh, Jong Soo

    2017-01-01

    The SAD (safety and arming device) is an indispensable fuse component that ensures safe and reliable performance during the use of ammunition. Because the application of electronic devices for smart munitions is increasing, miniaturization of the SAD has become one of the key issues for next-generation artillery fuses. Based on MEMS technology, various types of miniaturized SADs have been proposed and fabricated. However, none of them have been reported to have been used in actual munitions due to their lack of high impact endurance and complicated explosive train arrangements. In this research, a new MEMS SAD using a ball driven mechanism, is successfully demonstrated based on a UV LIGA (lithography, electroplating and molding) process. Unlike other MEMS SADs, both high impact endurance and simple structure were achieved by using a ball driven mechanism. The simple structural design also simplified the fabrication process and increased the processing yield. The ball driven type MEMS SAD performed successfully under the desired safe and arming conditions of a spin test and showed fine agreement with the FEM simulation result, conducted prior to its fabrication. A field test was also performed with a grenade launcher to evaluate the SAD performance in the firing environment. All 30 of the grenade samples equipped with the proposed MEMS SAD operated successfully under the high-G setback condition.

  4. Market segmentation: Venezuelan ADRs

    Directory of Open Access Journals (Sweden)

    Urbi Garay

    2012-12-01

    Full Text Available The control on foreign exchange imposed by Venezuela in 2003 constitute a natural experiment that allows researchers to observe the effects of exchange controls on stock market segmentation. This paper provides empirical evidence that although the Venezuelan capital market as a whole was highly segmented before the controls were imposed, the shares in the firm CANTV were, through their American Depositary Receipts (ADRs, partially integrated with the global market. Following the imposition of the exchange controls this integration was lost. Research also documents the spectacular and apparently contradictory rise experienced by the Caracas Stock Exchange during the serious economic crisis of 2003. It is argued that, as it happened in Argentina in 2002, the rise in share prices occurred because the depreciation of the Bolívar in the parallel currency market increased the local price of the stocks that had associated ADRs, which were negotiated in dollars.

  5. Segmentation Using Symmetry Deviation

    DEFF Research Database (Denmark)

    Hollensen, Christian; Højgaard, L.; Specht, L.;

    2011-01-01

    segmentations on manual contours was evaluated using concordance index and sensitivity for the hypopharyngeal patients. The resulting concordance index and sensitivity was compared with the result of using a threshold of 3 SUV using a paired t-test. Results: The anatomical and symmetrical atlas was constructed...... and sensitivity of respectively 0.43±0.15 and 0.56±0.18 was acquired. It was compared to the concordance index of segmentation using absolute threshold of 3 SUV giving respectively 0.41±0.16 and 0.51±0.19 for concordance index and sensitivity yielding p-values of 0.33 and 0.01 for a paired t-test respectively....

  6. Modeling of Human Joint Structures.

    Science.gov (United States)

    1982-09-01

    Radial Lateral " epicondyle Olecranon Radius Ulna Figure 3. Lateral aspect of the right elbow joint. -17- Annular Ligament This strong band encircles... elbow joint, knee joint, human joints, shoulder joint, ankle joint, joint models, hip joint, ligaments. 20. ABSTRACT (Continue on reverse side If...ligaments. -A rather extended discussion of the articulations and anatomical descriptions of the elbow , shoulder, hip, knee and ankle joints are

  7. Connecting textual segments

    DEFF Research Database (Denmark)

    Brügger, Niels

    2017-01-01

    In “Connecting textual segments: A brief history of the web hyperlink” Niels Brügger investigates the history of one of the most fundamental features of the web: the hyperlink. Based on the argument that the web hyperlink is best understood if it is seen as another step in a much longer and broader......-alone computers and in local and global digital networks....

  8. Random local binary pattern based label learning for multi-atlas segmentation

    Science.gov (United States)

    Zhu, Hancan; Cheng, Hewei; Fan, Yong

    2015-03-01

    Multi-atlas segmentation method has attracted increasing attention in the field of medical image segmentation. It segments the target image by combining warped atlas labels according to a label fusion strategy, usually based on the intensity information of the target and atlas images. However, it has been demonstrated that image intensity information itself is not discriminative enough for distinguishing different subcortical structures in brain magnetic resonance (MR) images. Recent advance in multi-atlas based segmentation has witnessed success of label fusion methods built on informative image features. The key component in these methods is the image feature extraction. Conventional image feature extraction methods, such as textural feature extraction, are built on manually designed image filters and their performance varies when applied to different segmentation problems. In this paper, we propose a random local binary pattern (RLBP) method to generate image features in a random fashion. Based on RLBP features, we use a local learning strategy to fuse labels in multi-atlas based segmentation. Our method has been validated for segmenting hippocampus from MR images. The experiment results have demonstrated that our method can achieve competitive segmentation performance as the state-of-the-art methods.

  9. Market segmentation in behavioral perspective.

    OpenAIRE

    Wells, V.K.; Chang, S. W.; Oliveira-Castro, J.M.; Pallister, J.

    2010-01-01

    A segmentation approach is presented using both traditional demographic segmentation bases (age, social class/occupation, and working status) and a segmentation by benefits sought. The benefits sought in this case are utilitarian and informational reinforcement, variables developed from the Behavioral Perspective Model (BPM). Using data from 1,847 consumers and from a total of 76,682 individual purchases, brand choice and price and reinforcement responsiveness were assessed for each segment a...

  10. Seismic design or retrofit of buildings with metallic structural fuses by the damage-reduction spectrum

    Science.gov (United States)

    Li, Gang; Jiang, Yi; Zhang, Shuchuan; Zeng, Yan; Li, Qiang

    2015-03-01

    Recently, the structural fuse has become an important issue in the field of earthquake engineering. Due to the trilinearity of the pushover curve of buildings with metallic structural fuses, the mechanism of the structural fuse is investigated through the ductility equation of a single-degree-of-freedom system, and the corresponding damage-reduction spectrum is proposed to design and retrofit buildings. Furthermore, the controlling parameters, the stiffness ratio between the main frame and structural fuse and the ductility factor of the main frame, are parametrically studied, and it is shown that the structural fuse concept can be achieved by specific combinations of the controlling parameters based on the proposed damage-reduction spectrum. Finally, a design example and a retrofit example, variations of real engineering projects after the 2008 Wenchuan earthquake, are provided to demonstrate the effectiveness of the proposed design procedures using buckling restrained braces as the structural fuses.

  11. Market Segmentation for Information Services.

    Science.gov (United States)

    Halperin, Michael

    1981-01-01

    Discusses the advantages and limitations of market segmentation as strategy for the marketing of information services made available by nonprofit organizations, particularly libraries. Market segmentation is defined, a market grid for libraries is described, and the segmentation of information services is outlined. A 16-item reference list is…

  12. Segmenting the Adult Education Market.

    Science.gov (United States)

    Aurand, Tim

    1994-01-01

    Describes market segmentation and how the principles of segmentation can be applied to the adult education market. Indicates that applying segmentation techniques to adult education programs results in programs that are educationally and financially satisfying and serve an appropriate population. (JOW)

  13. Market Segmentation for Information Services.

    Science.gov (United States)

    Halperin, Michael

    1981-01-01

    Discusses the advantages and limitations of market segmentation as strategy for the marketing of information services made available by nonprofit organizations, particularly libraries. Market segmentation is defined, a market grid for libraries is described, and the segmentation of information services is outlined. A 16-item reference list is…

  14. Segmenting the Adult Education Market.

    Science.gov (United States)

    Aurand, Tim

    1994-01-01

    Describes market segmentation and how the principles of segmentation can be applied to the adult education market. Indicates that applying segmentation techniques to adult education programs results in programs that are educationally and financially satisfying and serve an appropriate population. (JOW)

  15. MP Joint Arthritis

    Science.gov (United States)

    ... Find a Hand Surgeon Home Anatomy MP Joint Arthritis Email to a friend * required fields From * To * ... important for both pinching and gripping. MP joint arthritis is most common in the thumb and index ...

  16. Culture - joint fluid

    Science.gov (United States)

    Joint fluid culture ... fungi, or viruses grow. This is called a culture. If these germs are detected, other tests may ... is no special preparation needed for the lab culture. How to prepare for the removal of joint ...

  17. Sacroiliac joint pain - aftercare

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000610.htm Sacroiliac joint pain - aftercare To use the sharing features on this page, please enable JavaScript. The sacroiliac joint (SIJ) is a term used to describe the ...

  18. Knee joint replacement - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100088.htm Knee joint replacement - series—Normal anatomy To use the ... to slide 4 out of 4 Overview The knee is a complex joint. It contains the distal ...

  19. Joint Multi-Focus Fusion and Bayer ImageRestoration

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    In this paper, a joint multifocus image fusion and Bayer pattern image restoration algorithm for raw images of single-sensor colorimaging devices is proposed. Different from traditional fusion schemes, the raw Bayer pattern images are fused before colorrestoration. Therefore, the Bayer image restoration operation is only performed one time. Thus, the proposed algorithm is moreefficient than traditional fusion schemes. In detail, a clarity measurement of Bayer pattern image is defined for raw Bayer patternimages, and the fusion operator is performed on superpixels which provide powerful grouping cues of local image feature. Theraw images are merged with refined weight map to get the fused Bayer pattern image, which is restored by the demosaicingalgorithm to get the full resolution color image. Experimental results demonstrate that the proposed algorithm can obtain betterfused results with more natural appearance and fewer artifacts than the traditional algorithms.

  20. Adjacent Segment Pathology after Anterior Cervical Fusion.

    Science.gov (United States)

    Chung, Jae Yoon; Park, Jong-Beom; Seo, Hyoung-Yeon; Kim, Sung Kyu

    2016-06-01

    Anterior cervical fusion has become a standard of care for numerous pathologic conditions of the cervical spine. However, subsequent development of clinically significant disc disease at levels adjacent to fused discs is a serious long-term complication of this procedure. As more patients live longer after surgery, it is foreseeable that adjacent segment pathology (ASP) will develop in increasing numbers of patients. Also, ASP has been studied more intensively with the recent popularity of motion preservation technologies like total disc arthroplasty. The true nature and scope of ASP remains poorly understood. The etiology of ASP is most likely multifactorial. Various factors including altered biomechanical stresses, surgical disruption of soft tissue and the natural history of cervical disc disease contribute to the development of ASP. General factors associated with disc degeneration including gender, age, smoking and sports may play a role in the development of ASP. Postoperative sagittal alignment and type of surgery are also considered potential causes of ASP. Therefore, a spine surgeon must be particularly careful to avoid unnecessary disruption of the musculoligamentous structures, reduced risk of direct injury to the disc during dissection and maintain a safe margin between the plate edge and adjacent vertebrae during anterior cervical fusion.

  1. Managing Joint Production Motivation

    DEFF Research Database (Denmark)

    Lindenberg, Siegwart; Foss, Nicolai Juul

    2011-01-01

    We contribute to the microfoundations of organizational performance by proffering the construct of joint production motivation. Under such motivational conditions individuals see themselves as part of a joint endeavor, each with his or her own roles and responsibilities; generate shared represent...... representations of actions and tasks; cognitively coordinate cooperation; and choose their own behaviors in terms of joint goals. Using goal-framing theory, we explain how motivation for joint production can be managed by cognitive/symbolic management and organizational design....

  2. FUSE Observations of Comet C/2001 Q4 (NEAT)

    Science.gov (United States)

    Feldman, P. D.; Weaver, H. A.; Christian, D.; Combi, M. R.; Krasnopolsky, V.; Lisse, C. M.; Mumma, M. J.; Shemansky, D. E.; Stern, S. A.

    2004-11-01

    We report observations of comet C/2001 Q4 (NEAT) with the Far Ultraviolet Spectroscopic Explorer (FUSE) beginning 00:40 UT on 2004 April 24. This was the first moving target observation made by FUSE since the failure of two reaction wheels in December 2001. Spectra were obtained in the 905--1180 Å range at 0.3 Å spectral resolution using the 30'' × 30'' aperture and closely resemble the spectra of three comets observed in 2001 and reported previously. The principal features are the (0,0) bands of the CO Birge-Hopfield systems, atomic lines of \\ion{O}{1} and \\ion{H}{1}, and three lines of the H2 Lyman pumped by solar Lyman-β fluorescence. The CO C - X (0,0) band showed a nearly sinusoidal variation over the 27 hr observation interval with a period of 17.0 hr and a peak to minimum ratio of 1.56. The derived average CO production rate is Q(CO) = 8 × 1027 molecules s-1 which is about 4% that of H2O based on concurrent HST/STIS observations of OH emission. As in the previous observations, only upper limits are found for emission from \\ion{Ar}{1} and N2. A relatively strong feature near 1031.8 Å is most likely the H2 Werner (1,1) Q3 line pumped by solar \\ion{O}{6} and \\ion{N}{3}, as the corresponding lines in the (1,3) and (1,4) bands are also present. There may be evidence for weak \\ion{O}{6} emission at 1031.9 Å, in the wing of the H2 line, and at 1037.6 Å. The roughly two dozen other emissions that were not identified in the earlier spectra are also present in C/2001 Q4 at comparable strength to those in comet C/2001 A2 (LINEAR). As C/2001 A2 had a comparable water production rate to that of C/2001 Q4 at the time of observation, the source(s) of these emissions may be ubiquitous in comets. This work is based on data obtained by the NASA-CNES-CSA FUSE mission operated by The Johns Hopkins University. Financial support was partly provided by NASA contract NAS5-32985.

  3. Reliability of Tubular Joints

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Thoft-Christensen, Palle

    of the test is partly to obtain empirical data for the ultimate load-carrying capacity of tubular T-joints and partly to obtain some experience in performing tests with tubular joints. It is well known that tubular joints are usually designed in offshore engineering on the basis of empirical formulas obtained...

  4. High-voltage safety fuses for the transition-radiation tracking detector in the ATLAS experiment

    CERN Document Server

    Voronov, S A; Onishchenko, E M; Simakov, A B; Sosnovtsev, V V; Suchkov, S; Sugrobova, T A

    2004-01-01

    A safety fuse has been designed for the electrical protection of gas- filled detectors in the ATLAS experiment at CERN (Geneva, Switzerland). The fuse is a polished lithium niobate plate with a titanium strip of 91-kOmega resistance deposited by the photolithographic technique. The forced blowout time of the fuse is 10-50 ms; whereupon the leakage current through it is less than 1 nA at a 2-kV voltage. The resistance of the fuse case is greater than or equivalent equal' greater than 10**1**2 Omega. Its overall dimensions are 5.8 multiplied by 3.8 multiplied by 2 mm.

  5. Development of Fuses for Protection of Geiger-Mode Avalanche Photodiode Arrays

    Science.gov (United States)

    Grzesik, Michael; Bailey, Robert; Mahan, Joe; Ampe, Jim

    2015-11-01

    Current-limiting fuses composed of Ti/Al/Ni were developed for use in Geiger-mode avalanche photodiode arrays for each individual pixel in the array. The fuses were designed to burn out at ˜4.5 × 10-3 A and maintain post-burnout leakage currents less than 10-7 A at 70 V sustained for several minutes. Experimental fuse data are presented and successful incorporation of the fuses into a 256 × 64 pixel InP-based Geiger-mode avalanche photodiode array is reported.

  6. Optimized condition for etching fused-silica phase gratings with inductively coupled plasma technology.

    Science.gov (United States)

    Wang, Shunquan; Zhou, Changhe; Ru, Huayi; Zhang, Yanyan

    2005-07-20

    Polymer deposition is a serious problem associated with the etching of fused silica by use of inductively coupled plasma (ICP) technology, and it usually prevents further etching. We report an optimized etching condition under which no polymer deposition will occur for etching fused silica with ICP technology. Under the optimized etching condition, surfaces of the fabricated fused silica gratings are smooth and clean. Etch rate of fused silica is relatively high, and it demonstrates a linear relation between etched depth and working time. Results of the diffraction of gratings fabricated under the optimized etching condition match theoretical results well.

  7. Threats to ICF reactor materials: computational simulations of radiation damage induced topological changes in fused silica

    CERN Document Server

    Kubota, A; Stolken, J; Sadigh, B; Reyes, S; Rubia, T D; Latkowski, J F

    2003-01-01

    We have performed molecular dynamics simulations of radiation damage in fused silica. In this study, we discuss the role of successive cascade overlap on the saturation and self-healing of oxygen vacancy defects in the amorphous fused silica network. Furthermore, we present findings on the topological changes in fused silica due to repeated energetic recoil atoms. These topological network modifications consistent with experimental Raman spectroscopic observation on neutron and ion irradiated fused silica are indicators of permanent densification that has also been observed experimentally.

  8. A Fused Maxillary Central Incisor and Its Multidisciplinary Treatment: An 18-Year Follow-Up

    Directory of Open Access Journals (Sweden)

    Lluís Brunet-Llobet

    2014-01-01

    Full Text Available Fused teeth may cause aesthetic, spacing, periodontal, eruption, and caries problems. The present case report describes a 7-year-old boy patient with a chief complaint of unerupted maxillary incisor. Radiographic examination indicated a fused tooth which had two fused roots but two independent root canals. A complex management of a fused tooth is really difficult to standardize. In this case an orthodontic, endodontic, and surgical treatment (intentional replantation allowed the tooth to be retained until 18 years following intervention. Maintenance of the root and alveolar bone in young adults at least until full skeletal maturation should be the main treatment objective.

  9. Fusing two cytochromes b of Rhodobacter capsulatus cytochrome bc1 using various linkers defines a set of protein templates for asymmetric mutagenesis.

    Science.gov (United States)

    Czapla, Monika; Borek, Arkadiusz; Sarewicz, Marcin; Osyczka, Artur

    2012-01-01

    Cytochrome bc(1) (mitochondrial complex III), one of the key enzymes of biological energy conversion, is a functional homodimer in which each monomer contains three catalytic subunits: cytochrome c(1), the iron-sulfur subunit and cytochrome b. The latter is composed of eight transmembrane α-helices which, in duplicate, form a hydrophobic core of a dimer. We show that two cytochromes b can be fused into one 16-helical subunit using a number of different peptide linkers that vary in length but all connect the C-terminus of one cytochrome with the N-terminus of the other. The fusion proteins replace two cytochromes b in the dimer defining a set of available protein templates for introducing mutations that allow breaking symmetry of a dimer. A more detailed comparison of the form with the shortest, 3 amino acid, linker to the form with 12 amino acid linker established that both forms display similar level of structural plasticity to accommodate several, but not all, asymmetric patterns of mutations that knock out individual segments of cofactor chains. While the system based on a fused gene does not allow for the assessments of the functionality of electron-transfer paths in vivo, the family of proteins with fused cytochrome b offers attractive model for detailed investigations of molecular mechanism of catalysis at in vitro/reconstitution level.

  10. Bottom-up estimation of joint moments during manual lifting using orientation sensors instead of position sensors.

    Science.gov (United States)

    Faber, Gert S; Kingma, Idsart; van Dieën, Jaap H

    2010-05-01

    L5/S1, hip and knee moments during manual lifting tasks are, in a laboratory environment, frequently established by bottom-up inverse dynamics, using force plates to measure ground reaction forces (GRFs) and an optoelectronic system to measure segment positions and orientations. For field measurements, alternative measurement systems are being developed. One alternative is the use of small body-mounted inertial/magnetic sensors (IMSs) and instrumented force shoes to measure segment orientation and GRFs, respectively. However, because IMSs measure segment orientations only, the positions of segments relative to each other and relative to the GRFs have to be determined by linking them, assuming fixed segment lengths and zero joint translation. This will affect the estimated joint positions and joint moments. This study investigated the effect of using segment orientations only (orientation-based method) instead of using orientations and positions (reference method) on three-dimensional joint moments. To compare analysis methods (and not measurement methods), GRFs were measured with a force plate and segment positions and/or orientations were measured using optoelectronic marker clusters for both analysis methods. Eleven male subjects lifted a box from floor level using three lifting techniques: a stoop, a semi-squat and a squat technique. The difference between the two analysis methods remained small for the knee moments: knee joint and with reasonable accuracy at the hip and L5/S1 joints using segment orientation and GRF data only.

  11. Note: Discharging fused silica test masses with ionized nitrogen

    Science.gov (United States)

    Ugolini, D.; Funk, Q.; Amen, T.

    2011-04-01

    We have developed a technique for discharging fused silica test masses in a gravitational-wave interferometer with nitrogen ionized by an electron beam. The electrons are produced from a heated filament by thermionic emission in a low-pressure region to avoid contamination and burnout. Some electrons then pass through a small aperture and ionize nitrogen in a higher-pressure region, and this ionized gas is pumped across the test mass surface, neutralizing both polarities of charge. The discharge rate varies exponentially with charge density and filament current, quadratically with filament potential, and has an optimal working pressure of ˜8 mT. Adapting the technique to larger test mass chambers is also discussed.

  12. Fusing Quantitative Requirements Analysis with Model-based Systems Engineering

    Science.gov (United States)

    Cornford, Steven L.; Feather, Martin S.; Heron, Vance A.; Jenkins, J. Steven

    2006-01-01

    A vision is presented for fusing quantitative requirements analysis with model-based systems engineering. This vision draws upon and combines emergent themes in the engineering milieu. "Requirements engineering" provides means to explicitly represent requirements (both functional and non-functional) as constraints and preferences on acceptable solutions, and emphasizes early-lifecycle review, analysis and verification of design and development plans. "Design by shopping" emphasizes revealing the space of options available from which to choose (without presuming that all selection criteria have previously been elicited), and provides means to make understandable the range of choices and their ramifications. "Model-based engineering" emphasizes the goal of utilizing a formal representation of all aspects of system design, from development through operations, and provides powerful tool suites that support the practical application of these principles. A first step prototype towards this vision is described, embodying the key capabilities. Illustrations, implications, further challenges and opportunities are outlined.

  13. Does oligomerization in fused thiophene affect reactivity and aromaticity?

    Indian Academy of Sciences (India)

    Siddhartha Kr Purkayastha; Pradip Kr Bhattacharyya

    2016-02-01

    Reactivity and aromaticity of a few fused thiophene oligomers and their conformers are discussed in the light of density functional theory (DFT) and conceptual density functional theory. Reactivity parameters, such as hardness () and electrophilicity (), chemical potential () and energy of the HOMO (highest occupied molecular orbital) have been studied. Oligomerization raises the HOMO of the species, which in turn increases the reactivity of the oligomers. The absorption spectra of the species are analysed using TDDFT (time dependent density functional theory). The absorption peaks show red shift with increasing size of the oligomers. Aromaticity of the species is gauged by nucleus independent chemical shift (NICS). The out-of-plane component, (NICSzz) values advocate higher aromatic character at longer distance whereas, NICS supports the reverse.

  14. Fused Adaptive Lasso for Spatial and Temporal Quantile Function Estimation

    KAUST Repository

    Sun, Ying

    2015-09-01

    Quantile functions are important in characterizing the entire probability distribution of a random variable, especially when the tail of a skewed distribution is of interest. This article introduces new quantile function estimators for spatial and temporal data with a fused adaptive Lasso penalty to accommodate the dependence in space and time. This method penalizes the difference among neighboring quantiles, hence it is desirable for applications with features ordered in time or space without replicated observations. The theoretical properties are investigated and the performances of the proposed methods are evaluated by simulations. The proposed method is applied to particulate matter (PM) data from the Community Multiscale Air Quality (CMAQ) model to characterize the upper quantiles, which are crucial for studying spatial association between PM concentrations and adverse human health effects. © 2016 American Statistical Association and the American Society for Quality.

  15. Loss of suppressor-of-fused function promotes tumorigenesis.

    Science.gov (United States)

    Lee, Y; Kawagoe, R; Sasai, K; Li, Y; Russell, H R; Curran, T; McKinnon, P J

    2007-09-27

    The Sonic Hedgehog (SHH) signaling pathway is indispensable for development, and functions to activate a transcriptional program modulated by the GLI transcription factors. Here, we report that loss of a regulator of the SHH pathway, Suppressor of Fused (Sufu), resulted in early embryonic lethality in the mouse similar to inactivation of another SHH regulator, Patched1 (Ptch1). In contrast to Ptch1+/- mice, Sufu+/- mice were not tumor prone. However, in conjunction with p53 loss, Sufu+/- animals developed tumors including medulloblastoma and rhabdomyosarcoma. Tumors present in Sufu+/-p53-/- animals resulted from Sufu loss of heterozygosity. Sufu+/-p53-/- medulloblastomas also expressed a signature gene expression profile typical of aberrant SHH signaling, including upregulation of N-myc, Sfrp1, Ptch2 and cyclin D1. Finally, the Smoothened inhibitor, hedgehog antagonist, did not block growth of tumors arising from Sufu inactivation. These data demonstrate that Sufu is essential for development and functions as a tumor suppressor.

  16. Fabrication of microchannels in fused silica using femtosecond Bessel beams

    Energy Technology Data Exchange (ETDEWEB)

    Yashunin, D. A., E-mail: yashuninda@yandex.ru [Institute of Applied Physics of the Russian Academy of Sciences, 46 Ulyanov Str., Nizhny Novgorod 603950 (Russian Federation); Nizhny Novgorod State Technical University, 24 Minin St., Nizhny Novgorod 603950 (Russian Federation); Malkov, Yu. A. [Institute of Applied Physics of the Russian Academy of Sciences, 46 Ulyanov Str., Nizhny Novgorod 603950 (Russian Federation); Mochalov, L. A.; Stepanov, A. N. [Institute of Applied Physics of the Russian Academy of Sciences, 46 Ulyanov Str., Nizhny Novgorod 603950 (Russian Federation); Nizhny Novgorod State Technical University, 24 Minin St., Nizhny Novgorod 603950 (Russian Federation); Lobachevsky State University of Nizhny Novgorod, 23 Gagarin Ave., Nizhny Novgorod 603950 (Russian Federation)

    2015-09-07

    Extended birefringent waveguiding microchannels up to 15 mm long were created inside fused silica by single-pulse irradiation with femtosecond Bessel beams. The birefringent refractive index change of 2–4 × 10{sup −4} is attributed to residual mechanical stress. The microchannels were chemically etched in KOH solution to produce 15 mm long microcapillaries with smooth walls and a high aspect ratio of 1:250. Bessel beams provide higher speed of material processing compared to conventional multipulse femtosecond laser micromachining techniques and permit simple control of the optical axis direction of the birefringent waveguides, which is important for practical applications [Corrielli et al., “Rotated waveplates in integrated waveguide optics,” Nat. Commun. 5, 4249 (2014)].

  17. Watermarking for Fused Deposition Modeling by Seam Placement

    Directory of Open Access Journals (Sweden)

    Baumann Felix W.

    2017-01-01

    Full Text Available With the increased usage and application of 3D-printing or Additive Manufacturing (AM the question arises of how content providers or creators can ensure their intellectual property on such model data. Similar to other digital media such object information that is represented in a number of file formats is easy to copy and reproduce lossless. This research contributes by a proposition of a watermarking schema for Fused Deposition Modeling (FDM type 3D-printers. This system embeds information into the 3D-printed object without alterations to the structure or geometry by altering the entry points of each layer in a specific manner. With such a watermarking schema employed objects can be embedded with additional information such as a serial number or other traceable information.

  18. Characterization of the polishing induced contamination of fused silica optics

    Science.gov (United States)

    Pfiffer, Mathilde; Longuet, Jean-Louis; Labrugère, Christine; Fargin, Evelyne; Bousquet, Bruno; Dussauze, Marc; Lambert, Sébastien; Cormont, Philippe; Néauport, Jérôme

    2016-12-01

    Secondary Ion Mass Spectroscopy (SIMS), Electron Probe Micro Analysis (EPMA) and X-Ray Photoelectron Spectroscopy (XPS) were used to analyze the polishing induced contamination layer at the fused silica optics surface. Samples were prepared using an MRF polishing machine and cerium-based slurry. The cerium and iron penetration and concentration were measured in the surface out of defects. Cerium is embedded at the surface in a 60 nm layer and concentrated at 1200 ppmw in this layer while iron concentration falls down at 30 nm. Spatial distribution and homogeneity of the pollution were also studied in scratches and bevel using SIMS and EPMA techniques. An overconcentration was observed in the chamfer and we saw evidence that surface defects such as scratches are specific places that hold the pollutants. A wet etching was able to completely remove the contamination in the scratch.

  19. Fusing Quantitative Requirements Analysis with Model-based Systems Engineering

    Science.gov (United States)

    Cornford, Steven L.; Feather, Martin S.; Heron, Vance A.; Jenkins, J. Steven

    2006-01-01

    A vision is presented for fusing quantitative requirements analysis with model-based systems engineering. This vision draws upon and combines emergent themes in the engineering milieu. "Requirements engineering" provides means to explicitly represent requirements (both functional and non-functional) as constraints and preferences on acceptable solutions, and emphasizes early-lifecycle review, analysis and verification of design and development plans. "Design by shopping" emphasizes revealing the space of options available from which to choose (without presuming that all selection criteria have previously been elicited), and provides means to make understandable the range of choices and their ramifications. "Model-based engineering" emphasizes the goal of utilizing a formal representation of all aspects of system design, from development through operations, and provides powerful tool suites that support the practical application of these principles. A first step prototype towards this vision is described, embodying the key capabilities. Illustrations, implications, further challenges and opportunities are outlined.

  20. Thermal annealing of laser damage precursors on fused silica surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Shen, N; Miller, P E; Bude, J D; Laurence, T A; Suratwala, T I; Steele, W A; Feit, M D; Wang, L L

    2012-03-19

    Previous studies have identified two significant precursors of laser damage on fused silica surfaces at fluenes below {approx} 35 J/cm{sup 2}, photoactive impurities in the polishing layer and surface fractures. In the present work, isothermal heating is studied as a means of remediating the highly absorptive, defect structure associated with surface fractures. A series of Vickers indentations were applied to silica surfaces at loads between 0.5N and 10N creating fracture networks between {approx} 10{micro}m and {approx} 50{micro}m in diameter. The indentations were characterized prior to and following thermal annealing under various times and temperature conditions using confocal time-resolved photo-luminescence (CTP) imaging, and R/1 optical damage testing with 3ns, 355nm laser pulses. Significant improvements in the damage thresholds, together with corresponding reductions in CTP intensity, were observed at temperatures well below the glass transition temperature (T{sub g}). For example, the damage threshold on 05.N indentations which typically initiates at fluences <8 J/cm{sup 2} could be improved >35 J/cm{sup 2} through the use of a {approx} 750 C thermal treatment. Larger fracture networks required longer or higher temperature treatment to achieve similar results. At an annealing temperature > 1100 C, optical microscopy indicates morphological changes in some of the fracture structure of indentations, although remnants of the original fracture and significant deformation was still observed after thermal annealing. This study demonstrates the potential of using isothermal annealing as a means of improving the laser damage resistance of fused silica optical components. Similarly, it provides a means of further understanding the physics associated with optical damage and related mitigation processes.

  1. Case retrieval in medical databases by fusing heterogeneous information.

    Science.gov (United States)

    Quellec, Gwénolé; Lamard, Mathieu; Cazuguel, Guy; Roux, Christian; Cochener, Béatrice

    2011-01-01

    A novel content-based heterogeneous information retrieval framework, particularly well suited to browse medical databases and support new generation computer aided diagnosis (CADx) systems, is presented in this paper. It was designed to retrieve possibly incomplete documents, consisting of several images and semantic information, from a database; more complex data types such as videos can also be included in the framework. The proposed retrieval method relies on image processing, in order to characterize each individual image in a document by their digital content, and information fusion. Once the available images in a query document are characterized, a degree of match, between the query document and each reference document stored in the database, is defined for each attribute (an image feature or a metadata). A Bayesian network is used to recover missing information if need be. Finally, two novel information fusion methods are proposed to combine these degrees of match, in order to rank the reference documents by decreasing relevance for the query. In the first method, the degrees of match are fused by the Bayesian network itself. In the second method, they are fused by the Dezert-Smarandache theory: the second approach lets us model our confidence in each source of information (i.e., each attribute) and take it into account in the fusion process for a better retrieval performance. The proposed methods were applied to two heterogeneous medical databases, a diabetic retinopathy database and a mammography screening database, for computer aided diagnosis. Precisions at five of 0.809 ± 0.158 and 0.821 ± 0.177, respectively, were obtained for these two databases, which is very promising.

  2. FUSE Spectroscopy of the Accreting Hot Components in Symbiotic Variables

    Science.gov (United States)

    Sion, Edward M.; Godon, Patrick; Mikolajewska, Joanna; Sabra, Bassem; Kolobow, Craig

    2017-04-01

    We have conducted a spectroscopic analysis of the far-ultraviolet archival spectra of four symbiotic variables, EG And, AE Ara, CQ Dra, and RW Hya. RW Hya and EG And have never had a recorded outburst, while CQ Dra and AE Ara have outburst histories. We analyze these systems while they are in quiescence in order to help reveal the physical properties of their hot components via comparisons of the observations with optically thick accretion disk models and non-LTE model white dwarf photospheres. We have extended the wavelength coverage down to the Lyman limit with Far Ultraviolet Spectroscopic Explorer (FUSE) spectra. We find that the hot component in RW Hya is a low-mass white dwarf with a surface temperature of 160,000 K. We reexamine whether or not the symbiotic system CQ Dra is a triple system with a red giant transferring matter to a hot component made up of a cataclysmic variable in which the white dwarf has a surface temperature as low as ∼20,000 K. The very small size of the hot component contributing to the shortest wavelengths of the FUSE spectrum of CQ Dra agrees with an optically thick and geometrically thin (∼4% of the WD surface) hot (∼120,000 K) boundary layer. Our analysis of EG And reveals that its hot component is a hot, bare, low-mass white dwarf with a surface temperature of 80,000–95,000 K, with a surface gravity {log}(g)=7.5. For AE Ara, we also find that a low-gravity ({log}(g)∼ 6), hot (T∼ {{130,000}} K) WD accounts for the hot component.

  3. Characteristics Of Fused Couplers Below Cut-Off

    Science.gov (United States)

    Meyer, T. J.; Tekippe, V. J.

    1989-02-01

    A number of different architectures are being explored for the utilization of optical fiber in the subscriber loop. In addition to reliability and maintainability, cost is a prime consideration since full implementation of fiber in the local loop will not occur until it is economically viable. It is becoming increasingly clear that in order to accommodate a number of ISDN applications, including high definition television (HDTV), singlemode fiber with a singlemode laser at the terminal end will be required. The situation at the subscriber end is quite different, however. The data rates are expected to be low on the return path to allow for POTS ( plain old telephone service) and some data transfer. When this requirement is combined with cost and reliability considerations, the inexpensive lasers developed for the CD (compact disk) market become quite attractive. The biggest disadvantage of this source is that the fiber which is optimized for singlemode operation at 1300nm tends to be multimode in the 800nm band where these lasers operate. Previous papers have considered such effects as modal noise and pulse dispersion when using these lasers with fiber that is singlemode in the 1300nm band.[1] Another consideration is the passive components required to implement such an architecture. Figure 1 shows a typical bidirectional design with full duplex operation on a single fiber. The key component is the 800/1300 wavelength division multiplexer/demultiplexer (WDM). Because of the multimode nature of the fiber in the 800nm band, all fiber approaches to fabricating the WDM, such as the fused beconical taper (FBT) approach, raise new issues which are not encountered, for example, with 1300/1500nm WDM's.[2] In this paper we discuss the effects of the multimode behavior of the fiber on the performance of fused couplers and WDM's.

  4. Deep Dynamic Neural Networks for Multimodal Gesture Segmentation and Recognition

    OpenAIRE

    Wu, Di; Pigou, Lionel; Kindermans, Pieter-Jan; Le, Nam Do-Hoang; Shao, Ling; Dambre, Joni; Odobez, Jean-Marc

    2016-01-01

    This paper describes a novel method called Deep Dynamic Neural Networks (DDNN) for multimodal gesture recognition. A semi-supervised hierarchical dynamic framework based on a Hidden Markov Model (HMM) is proposed for simultaneous gesture segmentation and recognition where skeleton joint information, depth and RGB images, are the multimodal input observations. Unlike most traditional approaches that rely on the construction of complex handcrafted features, our approach learns high-level spatio...

  5. Signs of segmentation?

    DEFF Research Database (Denmark)

    Ilsøe, Anna

    2012-01-01

    This article addresses the contribution of decentralized collective bargaining to the development of different forms of flexicurity for different groups of employees on the Danish labour market. Based on five case studies of company-level bargaining on flexible working hours in Danish industry...... the text of the agreements. On the other hand, less flexible employees often face difficulties in meeting the demands of the agreements and may ultimately be forced to leave the company and rely on unemployment benefits and active labour market policies. In a flexicurity perspective, this development seems...... to imply a segmentation of the Danish workforce regarding hard and soft versions of flexicurity....

  6. Noncooperative Iris Segmentation

    Directory of Open Access Journals (Sweden)

    Elsayed Mostafa

    2012-01-01

    Full Text Available In noncooperative iris recognition one should deal with uncontrolled behavior of the subject as well as uncontrolled lighting conditions. That means eyelids and eyelashes occlusion, non uniform intensities, reflections, imperfect focus, and orientation among the others are to be considered. To cope with this situation a noncooperative iris segmentation algorithm based on numerically stable direct least squares fitting of ellipses model and modified Chan-Vese model (local binary fitting energy with variational level set formulation is to be proposed. The proposed algorithm is tested using CASIA-IrisV3.

  7. The LOFT Ground Segment

    DEFF Research Database (Denmark)

    Bozzo, E.; Antonelli, A.; Argan, A.;

    2014-01-01

    targets per orbit (~90 minutes), providing roughly ~80 GB of proprietary data per day (the proprietary period will be 12 months). The WFM continuously monitors about 1/3 of the sky at a time and provides data for about ~100 sources a day, resulting in a total of ~20 GB of additional telemetry. The LOFT...... we summarize the planned organization of the LOFT ground segment (GS), as established in the mission Yellow Book 1 . We describe the expected GS contributions from ESA and the LOFT consortium. A review is provided of the planned LOFT data products and the details of the data flow, archiving...

  8. On the expression of joint moments during gait.

    Science.gov (United States)

    Schache, Anthony G; Baker, Richard

    2007-03-01

    The purpose of the current study was to examine the effect of different reference frames on lower limb joint moments during gait with a view to identifying a recommended convention for clinical purposes. Data were collected from 10 subjects (nine able-bodied adults and one child with diplegic cerebral palsy) whilst walking at a self-selected speed. Calculations utilised a three-dimensional inverse dynamics model. For each joint, moments were expressed in four different reference frames. Three of the frames were orthogonal: laboratory frame; anatomical frame of proximal segment; anatomical frame of distal segment. The fourth reference frame was a non-orthogonal joint coordinate system (JCS). Significant differences in the joint moment profiles during gait were found with alternative references frames. This was apparent primarily for the transverse plane joint moments for able-bodied adult gait. For the pathological gait pattern presented, there were also marked differences in the frontal plane joint moments and more subtle ones in the sagittal plane. Whilst it is recognised that all possible reference frames for the expression of the net moment vector are mathematically valid, a decision needs to be made as to which one is more clinically useful. It is proposed that the non-orthogonal JCS is most logical on the basis of what, biomechanically, the joint moment actually represents.

  9. Analysed potential of big data and supervised machine learning techniques in effectively forecasting travel times from fused data

    Directory of Open Access Journals (Sweden)

    Ivana Šemanjski

    2015-12-01

    Full Text Available Travel time forecasting is an interesting topic for many ITS services. Increased availability of data collection sensors increases the availability of the predictor variables but also highlights the high processing issues related to this big data availability. In this paper we aimed to analyse the potential of big data and supervised machine learning techniques in effectively forecasting travel times. For this purpose we used fused data from three data sources (Global Positioning System vehicles tracks, road network infrastructure data and meteorological data and four machine learning techniques (k-nearest neighbours, support vector machines, boosting trees and random forest. To evaluate the forecasting results we compared them in-between different road classes in the context of absolute values, measured in minutes, and the mean squared percentage error. For the road classes with the high average speed and long road segments, machine learning techniques forecasted travel times with small relative error, while for the road classes with the small average speeds and segment lengths this was a more demanding task. All three data sources were proven itself to have a high impact on the travel time forecast accuracy and the best results (taking into account all road classes were achieved for the k-nearest neighbours and random forest techniques.

  10. A desymmetrization route to fused Troger's base analogues: synthesis, isolation, and characterization of the first anti-anti diastereomer of a fused tris-Troger's base analogue.

    Science.gov (United States)

    Hansson, Anna; Wixe, Torbjörn; Bergquist, Karl-Erik; Wärnmark, Kenneth

    2005-05-12

    A desymmetrization route to fused Troger's base analogues was developed. In this way, the synthesis of the first example of an anti-anti diastereomer of a fused tris-Troger's base analogue was accomplished. The resulting compound 5b is a nonlinear symmetric regioisomer obtained from p-bromoaniline in 7% yield. The corresponding syn-anti diastereomer 5a was obtained in 4% yield.

  11. Segmented Target Design

    Science.gov (United States)

    Merhi, Abdul Rahman; Frank, Nathan; Gueye, Paul; Thoennessen, Michael; MoNA Collaboration

    2013-10-01

    A proposed segmented target would improve decay energy measurements of neutron-unbound nuclei. Experiments like this have been performed at the National Superconducting Cyclotron Laboratory (NSCL) located at Michigan State University. Many different nuclei are produced in such experiments, some of which immediately decay into a charged particle and neutron. The charged particles are bent by a large magnet and measured by a suite of charged particle detectors. The neutrons are measured by the Modular Neutron Array (MoNA) and Large Multi-Institutional Scintillation Array (LISA). With the current target setup, a nucleus in a neutron-unbound state is produced with a radioactive beam impinged upon a beryllium target. The resolution of these measurements is very dependent on the target thickness since the nuclear interaction point is unknown. In a segmented target using alternating layers of silicon detectors and Be-targets, the Be-target in which the nuclear reaction takes place would be determined. Thus the experimental resolution would improve. This poster will describe the improvement over the current target along with the status of the design. Work supported by Augustana College and the National Science Foundation grant #0969173.

  12. Bayesian Parameter Estimation and Segmentation in the Multi-Atlas Random Orbit Model.

    Directory of Open Access Journals (Sweden)

    Xiaoying Tang

    Full Text Available This paper examines the multiple atlas random diffeomorphic orbit model in Computational Anatomy (CA for parameter estimation and segmentation of subcortical and ventricular neuroanatomy in magnetic resonance imagery. We assume that there exist multiple magnetic resonance image (MRI atlases, each atlas containing a collection of locally-defined charts in the brain generated via manual delineation of the structures of interest. We focus on maximum a posteriori estimation of high dimensional segmentations of MR within the class of generative models representing the observed MRI as a conditionally Gaussian random field, conditioned on the atlas charts and the diffeomorphic change of coordinates of each chart that generates it. The charts and their diffeomorphic correspondences are unknown and viewed as latent or hidden variables. We demonstrate that the expectation-maximization (EM algorithm arises naturally, yielding the likelihood-fusion equation which the a posteriori estimator of the segmentation labels maximizes. The likelihoods being fused are modeled as conditionally Gaussian random fields with mean fields a function of each atlas chart under its diffeomorphic change of coordinates onto the target. The conditional-mean in the EM algorithm specifies the convex weights with which the chart-specific likelihoods are fused. The multiple atlases with the associated convex weights imply that the posterior distribution is a multi-modal representation of the measured MRI. Segmentation results for subcortical and ventricular structures of subjects, within populations of demented subjects, are demonstrated, including the use of multiple atlases across multiple diseased groups.

  13. Bayesian Parameter Estimation and Segmentation in the Multi-Atlas Random Orbit Model.

    Science.gov (United States)

    Tang, Xiaoying; Oishi, Kenichi; Faria, Andreia V; Hillis, Argye E; Albert, Marilyn S; Mori, Susumu; Miller, Michael I

    2013-01-01

    This paper examines the multiple atlas random diffeomorphic orbit model in Computational Anatomy (CA) for parameter estimation and segmentation of subcortical and ventricular neuroanatomy in magnetic resonance imagery. We assume that there exist multiple magnetic resonance image (MRI) atlases, each atlas containing a collection of locally-defined charts in the brain generated via manual delineation of the structures of interest. We focus on maximum a posteriori estimation of high dimensional segmentations of MR within the class of generative models representing the observed MRI as a conditionally Gaussian random field, conditioned on the atlas charts and the diffeomorphic change of coordinates of each chart that generates it. The charts and their diffeomorphic correspondences are unknown and viewed as latent or hidden variables. We demonstrate that the expectation-maximization (EM) algorithm arises naturally, yielding the likelihood-fusion equation which the a posteriori estimator of the segmentation labels maximizes. The likelihoods being fused are modeled as conditionally Gaussian random fields with mean fields a function of each atlas chart under its diffeomorphic change of coordinates onto the target. The conditional-mean in the EM algorithm specifies the convex weights with which the chart-specific likelihoods are fused. The multiple atlases with the associated convex weights imply that the posterior distribution is a multi-modal representation of the measured MRI. Segmentation results for subcortical and ventricular structures of subjects, within populations of demented subjects, are demonstrated, including the use of multiple atlases across multiple diseased groups.

  14. Multi-Hypothesis CRF-Segmentation of Neural Tissue in Anisotropic EM Volumes

    CERN Document Server

    Funke, Jan; Hamprecht, Fred; Cardona, Albert; Cook, Matthew

    2011-01-01

    We present an approach for the joint segmentation and grouping of similar components in anisotropic 3D image data and use it to segment neural tissue in serial sections electron microscopy (EM) images. We first construct a nested set of neuron segmentation hypotheses for each slice. A conditional random field (CRF) then allows us to evaluate both the compatibility of a specific segmentation and a specific inter-slice assignment of neuron candidates with the underlying observations. The model is solved optimally for an entire image stack simultaneously using integer linear programming (ILP), which yields the maximum a posteriori solution in amortized linear time in the number of slices. We evaluate the performance of our approach on an annotated sample of the Drosophila larva neuropil and show that the consideration of different segmentation hypotheses in each slice leads to a significant improvement in the segmentation and assignment accuracy.

  15. Segmentation of the Infant Food Market

    OpenAIRE

    Hrůzová, Daniela

    2015-01-01

    The theoretical part covers general market segmentation, namely the marketing importance of differences among consumers, the essence of market segmentation, its main conditions and the process of segmentation, which consists of four consecutive phases - defining the market, determining important criteria, uncovering segments and developing segment profiles. The segmentation criteria, segmentation approaches, methods and techniques for the process of market segmentation are also described in t...

  16. Segmentation of the Infant Food Market

    OpenAIRE

    Hrůzová, Daniela

    2015-01-01

    The theoretical part covers general market segmentation, namely the marketing importance of differences among consumers, the essence of market segmentation, its main conditions and the process of segmentation, which consists of four consecutive phases - defining the market, determining important criteria, uncovering segments and developing segment profiles. The segmentation criteria, segmentation approaches, methods and techniques for the process of market segmentation are also described in t...

  17. Joint stiffness of the ankle and the knee in running.

    Science.gov (United States)

    Günther, Michael; Blickhan, Reinhard

    2002-11-01

    The spring-mass model is a valid fundament to understand global dynamics of fast legged locomotion under gravity. The underlying concept of elasticity, implying leg stiffness as a crucial parameter, is also found on lower motor control levels, i.e. in muscle-reflex and muscle-tendon systems. Therefore, it seems reasonable that global leg stiffness emerges from local elasticity established by appropriate joint torques. A recently published model of an elastically operating, segmented leg predicts that proper adjustment of joint elasticities to the leg geometry and initial conditions of ground contact provides internal leg stability. Another recent study suggests that in turn the leg segmentation and the initial conditions may be a consequence of metabolic and bone stress constraints. In this study, the theoretical predictions were verified experimentally with respect to initial conditions and elastic joint characteristics in human running. Kinematics and kinetics were measured and the joint torques were estimated by inverse dynamics. Stiffnesses and elastic nonlinearities describing the resulting joint characteristics were extracted from parameter fits. Our results clearly support the theoretical predictions: the knee joint is always stiffer and more extended than the ankle joint. Moreover, the knee torque characteristic on the average shows the higher nonlinearity. According to literature, the leg geometry is a consequence of metabolic and material stress limitations. Adapted to this given geometry, the initial joint angle conditions in fast locomotion are a compromise between metabolic and control effort minimisation. Based on this adaptation, an appropriate joint stiffness ratio between ankle and knee passively safeguards the internal leg stability. The identified joint nonlinearities contribute to the linearisation of the leg spring.

  18. Unsupervised segmentation of MRI knees using image partition forests

    Science.gov (United States)

    Marčan, Marija; Voiculescu, Irina

    2016-03-01

    Nowadays many people are affected by arthritis, a condition of the joints with limited prevention measures, but with various options of treatment the most radical of which is surgical. In order for surgery to be successful, it can make use of careful analysis of patient-based models generated from medical images, usually by manual segmentation. In this work we show how to automate the segmentation of a crucial and complex joint -- the knee. To achieve this goal we rely on our novel way of representing a 3D voxel volume as a hierarchical structure of partitions which we have named Image Partition Forest (IPF). The IPF contains several partition layers of increasing coarseness, with partitions nested across layers in the form of adjacency graphs. On the basis of a set of properties (size, mean intensity, coordinates) of each node in the IPF we classify nodes into different features. Values indicating whether or not any particular node belongs to the femur or tibia are assigned through node filtering and node-based region growing. So far we have evaluated our method on 15 MRI knee images. Our unsupervised segmentation compared against a hand-segmented gold standard has achieved an average Dice similarity coefficient of 0.95 for femur and 0.93 for tibia, and an average symmetric surface distance of 0.98 mm for femur and 0.73 mm for tibia. The paper also discusses ways to introduce stricter morphological and spatial conditioning in the bone labelling process.

  19. Facet joint changes after application of lumbar nonfusion dynamic stabilization.

    Science.gov (United States)

    Lee, Soo Eon; Jahng, Tae-Ahn; Kim, Hyun Jib

    2016-01-01

    OBJECTIVE The long-term effects on adjacent-segment pathology after nonfusion dynamic stabilization is unclear, and, in particular, changes at the adjacent facet joints have not been reported in a clinical study. This study aims to compare changes in the adjacent facet joints after lumbar spinal surgery. METHODS Patients who underwent monosegmental surgery at L4-5 with nonfusion dynamic stabilization using the Dynesys system (Dynesys group) or transforaminal lumbar interbody fusion with pedicle screw fixation (fusion group) were retrospectively compared. Facet joint degeneration was evaluated at each segment using the CT grading system. RESULTS The Dynesys group included 15 patients, while the fusion group included 22 patients. The preoperative facet joint degeneration CT grades were not different between the 2 groups. Compared with the preoperative CT grades, 1 side of the facet joints at L3-4 and L4-5 had significantly more degeneration in the Dynesys group. In the fusion group, significant facet joint degeneration developed on both sides at L2-3, L3-4, and L5-S1. The subjective back and leg pain scores were not different between the 2 groups during follow-up, but functional outcome based on the Oswestry Disability Index improved less in the fusion group than in the Dynesys group. CONCLUSIONS Nonfusion dynamic stabilization using the Dynesys system had a greater preventative effect on facet joint degeneration in comparison with that obtained using fusion surgery. The Dynesys system, however, resulted in facet joint degeneration at the instrumented segments and above. An improved physiological nonfusion dynamic stabilization system for lumbar spinal surgery should be developed.

  20. One-pot synthesis of 2-aryl-1,2-fused pyrimidones

    Indian Academy of Sciences (India)

    SAMIKANNU RAMESH; PON SARAVANAKUMAR; RAMASAMY DURAISAMY; ARVIND MATHUR; PIRAMA NAYAGAM ARUNACHALAM

    2017-03-01

    A facile and versatile method for the synthesis of alicyclic fused pyrimidones from aminoacrylates and lactams in the presence of phosphorous oxychloride is described. The results suggest that this method is widely applicable except for cyclobutyl fused systems. This method gives better yield than the method ofcondensing aminopyrrolidines with the beta keto esters.

  1. Using MERIS fused images for land-cover mapping vegetation status assessment in heterogeneous landscapes

    NARCIS (Netherlands)

    Zurita Milla, R.; Clevers, J.G.P.W.; Gijsel, J.A.E.; Schaepman, M.E.

    2011-01-01

    In this paper we evaluate the potential of ENVISAT–Medium Resolution Imaging Spectrometer (MERIS) fused images for land-cover mapping and vegetation status assessment in heterogeneous landscapes. A series of MERIS fused images (15 spectral bands; 25 m pixel size) is created using the linear mixing m

  2. 31 CFR 100.12 - Exchange of fused and mixed coins.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Exchange of fused and mixed coins. 100.12 Section 100.12 Money and Finance: Treasury Regulations Relating to Money and Finance EXCHANGE OF PAPER CURRENCY AND COIN Exchange of Coin § 100.12 Exchange of fused and mixed coins....

  3. High-voltage safety fuses for the transition-radiation tracking detector in the ATLAS experiment

    NARCIS (Netherlands)

    Voronov, SA; Voronov, YA; Onishchenko, EM; Simakov, AB; Sosnovtsev, VV; Suchkov, SI; Sugrobova, TA

    2004-01-01

    A safety fuse has been designed for the electrical protection of gas-filled detectors in the ATLAS experiment at CERN (Geneva, Switzerland). The fuse is a polished lithium niobate plate with a titanium strip of 91-kOmega resistance deposited by the photolithographic technique. The forced blow-out ti

  4. Statistical pattern recognition for rock joint images

    Science.gov (United States)

    Wang, Weixing; Bin, Cui

    2005-10-01

    As a cooperation project between Sweden and China, we sampled a number of rock specimens for analyze rock fracture network by optical image technique. The samples are resin injected, in which way; opened fractures can be seen clearly by means of UV (Ultraviolet) light illumination. In the study period, Recognition of rock fractures is crucial in many rock engineering applications. In order to successfully applying automatic image processing techniques for the problem of automatic (or semi-automatic) rock fracture detection and description, the key (and hardest task) is the automatic detection of fractures robustly in images. When statistical pattern recognition is used to segment a rock joint color image, features of different samples can be learned first, then, each pixel of the image is classified by these features. As the testing result showing, an attribute rock fracture image is segmented satisfactorily by using this way. The method can be widely used for other complicated images too. In this paper, Kernel Fisher discrimination (KFD) is employed to construct a statistical pattern recognition classifier. KFD can transform nonlinear discrimination in an attribute space with high dimension, into linear discrimination in a feature space with low dimension. While one needs not know the detailed mapping form from attribute space to feature space in the process of transformation. It is proved that this method performs well by segmenting complicated rock joint color images.

  5. Refractive index sensors based on the fused tapered special multi-mode fiber

    Science.gov (United States)

    Fu, Xing-hu; Xiu, Yan-li; Liu, Qin; Xie, Hai-yang; Yang, Chuan-qing; Zhang, Shun-yang; Fu, Guang-wei; Bi, Wei-hong

    2016-01-01

    In this paper, a novel refractive index (RI) sensor is proposed based on the fused tapered special multi-mode fiber (SMMF). Firstly, a section of SMMF is spliced between two single-mode fibers (SMFs). Then, the SMMF is processed by a fused tapering machine, and a tapered fiber structure is fabricated. Finally, a fused tapered SMMF sensor is obtained for measuring external RI. The RI sensing mechanism of tapered SMMF sensor is analyzed in detail. For different fused tapering lengths, the experimental results show that the RI sensitivity can be up to 444.517 81 nm/RIU in the RI range of 1.334 9—1.347 0. The RI sensitivity is increased with the increase of fused tapering length. Moreover, it has many advantages, including high sensitivity, compact structure, fast response and wide application range. So it can be used to measure the solution concentration in the fields of biochemistry, health care and food processing.

  6. CalFUSE v3: A Data-Reduction Pipeline for the Far Ultraviolet Spectroscopic Explorer

    CERN Document Server

    Dixon, W V; Barrett, P E; Civeit, T; Dupuis, J; Fullerton, A W; Godard, B; Hsu, J C; Kaiser, M E; Kruk, J W; Lacour, S; Lindler, D J; Massa, D; Robinson, R D; Romelfanger, M L; Sonnentrucker, P

    2007-01-01

    Since its launch in 1999, the Far Ultraviolet Spectroscopic Explorer (FUSE) has made over 4600 observations of some 2500 individual targets. The data are reduced by the Principal Investigator team at the Johns Hopkins University and archived at the Multimission Archive at Space Telescope (MAST). The data-reduction software package, called CalFUSE, has evolved considerably over the lifetime of the mission. The entire FUSE data set has recently been reprocessed with CalFUSE v3.2, the latest version of this software. This paper describes CalFUSE v3.2, the instrument calibrations upon which it is based, and the format of the resulting calibrated data files.

  7. Infrared target recognition based on improved joint local ternary pattern

    Science.gov (United States)

    Sun, Junding; Wu, Xiaosheng

    2016-05-01

    This paper presents a simple, efficient, yet robust approach, named joint orthogonal combination of local ternary pattern, for automatic forward-looking infrared target recognition. It gives more advantages to describe the macroscopic textures and microscopic textures by fusing variety of scales than the traditional LBP-based methods. In addition, it can effectively reduce the feature dimensionality. Further, the rotation invariant and uniform scheme, the robust LTP, and soft concave-convex partition are introduced to enhance its discriminative power. Experimental results demonstrate that the proposed method can achieve competitive results compared with the state-of-the-art methods.

  8. Automated CT segmentation of diseased hip using hierarchical and conditional statistical shape models.

    Science.gov (United States)

    Yokota, Futoshi; Okada, Toshiyuki; Takao, Masaki; Sugano, Nobuhiko; Tada, Yukio; Tomiyama, Noriyuki; Sato, Yoshinobu

    2013-01-01

    Segmentation of the femur and pelvis is a prerequisite for patient-specific planning and simulation for hip surgery. Accurate boundary determination of the femoral head and acetabulum is the primary challenge in diseased hip joints because of deformed shapes and extreme narrowness of the joint space. To overcome this difficulty, we investigated a multi-stage method in which the hierarchical hip statistical shape model (SSM) is initially utilized to complete segmentation of the pelvis and distal femur, and then the conditional femoral head SSM is used under the condition that the regions segmented during the previous stage are known. CT data from 100 diseased patients categorized on the basis of their disease type and severity, which included 200 hemi-hips, were used to validate the method, which delivered significantly increased segmentation accuracy for the femoral head.

  9. Analysis of Cliff-Ramp Structures in Homogeneous Scalar Turbulence by the Method of Line Segments

    Science.gov (United States)

    Gauding, Michael; Goebbert, Jens Henrik; Peters, Norbert; Hasse, Christian

    2015-11-01

    The local structure of a turbulent scalar field in homogeneous isotropic turbulence is analyzed by direct numerical simulations (DNS). A novel signal decomposition approach is introduced where the signal of the scalar along a straight line is partitioned into segments based on the local extremal points of the scalar field. These segments are then parameterized by the distance between adjacent extremal points and a segment-based gradient. Joint statistics of the length and the segment-based gradient provide novel understanding about the local structure of the turbulent field and particularly about cliff-ramp-like structures. Ramp-like structures are unveiled by the asymmetry of joint distribution functions. Cliff-like structures are further analyzed by conditional statistics and it is shown from DNS that the width of cliffs scales with the Kolmogorov length scale.

  10. Spatio-Temporal Video Object Segmentation via Scale-Adaptive 3D Structure Tensor

    Directory of Open Access Journals (Sweden)

    Hai-Yun Wang

    2004-06-01

    Full Text Available To address multiple motions and deformable objects' motions encountered in existing region-based approaches, an automatic video object (VO segmentation methodology is proposed in this paper by exploiting the duality of image segmentation and motion estimation such that spatial and temporal information could assist each other to jointly yield much improved segmentation results. The key novelties of our method are (1 scale-adaptive tensor computation, (2 spatial-constrained motion mask generation without invoking dense motion-field computation, (3 rigidity analysis, (4 motion mask generation and selection, and (5 motion-constrained spatial region merging. Experimental results demonstrate that these novelties jointly contribute much more accurate VO segmentation both in spatial and temporal domains.

  11. Determination of the spatial movement of the temporomandibular joints (tmj joint heads in patients with muscle and joint dysfunction according to computed tomography (ct

    Directory of Open Access Journals (Sweden)

    Аркадий Максимович Боян

    2015-11-01

    Full Text Available Computed tomography (CT is the one of most objective diagnostic methods of TMJ MJD it allows define amplitudes of joint heads movement in sagittal projections to detect an asymmetry of TMJ elements location.Aim of research. Assessment of location of mandibular joint heads and determination of its spatial position in patients with TMJ MJD before treatment and after it using CT.Materials and methods. 50 patients 28-62 years old, 37 women and 13 men who underwent computed tomography (CT of TMJ were under observation.The results of observation were analyzed in details.The studies were carried out using cone-radial computed tomographic scanner «Vatech Pax uni 3d». CT of TMJ was carried out in habitual occlusion before the start of treatment and after removal of TMJ MJD symptoms and complaints. At the study there were measured the width of joint fissure in front, upper and back segments according to N.A. Rabuhina methodology in N.E. Androsova and so-authors modification. Statistical analysis of the data received was carried out using «Statistics» (Statsoft, Inc program.Results. The results of TMJ CT in patients before the start of treatment demonstrated that the sizes of TMJ joint fissure were different. The width of the upper segment of TMJ joint fissure in patients before the start of treatment was reliably less (≤0,001 comparing with an analogous parameter in the group of patients after treatment that indicates the upper location of mandibular head in TMJ with reducing the height of the lower segment of face.So the data of study of the joint fissure width received using TMJ CT demonstrate formation of specific outlines of joint fissure at displacement of mandible and consequently joint head. Information about the joint fissure parameters allows rationally plan and realize orthopedic treatment and the necessary rehabilitation measures in patients with TMJ MJD.Conclusions. The studies demonstrated that the displacements of mandibular joint

  12. Sagittal alignment of the first metatarsophalangeal joint after arthrodesis for rheumatoid forefoot deformity.

    Science.gov (United States)

    Tanabe, Akihiko; Majima, Tokifumi; Onodera, Tomohiro; Sawaguchi, Naohiro; Watanabe, Takuya; Kasahara, Yasuhiko; Takahashi, Daisuke

    2013-01-01

    The present study assessed the midterm results of reconstruction for rheumatoid forefoot deformity with arthrodesis of the first metatarsophalangeal (MTP) joint, scarf osteotomy, resection arthroplasty of the metatarsal head of the lesser toes, and surgical repair of hammertoe deformity (arthrodesis of the proximal interphalangeal joint). Special focus was placed on the sagittal alignment of the first metatarsophalangeal joint after arthrodesis. We retrospectively evaluated the postoperative clinical outcomes and radiographic findings for 16 consecutive female patients (20 feet) with symptomatic rheumatoid forefoot deformities. The mean duration of follow-up was 7.9 (range 4 to 13) years. All first MTP joints and first metatarsal bones were fused successfully. The mean value of the American Orthopaedic Foot and Ankle Society and Japanese Society for Foot Surgery clinical scores significantly improved overall, except for 2 patients (10%), who complained of first toe pain at the final follow-up visit owing to sagittal misalignment of the fused first MTP joint. Sagittal alignment of the first metatarsal varies greatly because of the rheumatoid midfoot and hindfoot deformities. Therefore, inclination of the first metatarsal should be considered when determining the first MTP joint sagittal fusion angle.

  13. Segmented heat exchanger

    Science.gov (United States)

    Baldwin, Darryl Dean; Willi, Martin Leo; Fiveland, Scott Byron; Timmons, Kristine Ann

    2010-12-14

    A segmented heat exchanger system for transferring heat energy from an exhaust fluid to a working fluid. The heat exchanger system may include a first heat exchanger for receiving incoming working fluid and the exhaust fluid. The working fluid and exhaust fluid may travel through at least a portion of the first heat exchanger in a parallel flow configuration. In addition, the heat exchanger system may include a second heat exchanger for receiving working fluid from the first heat exchanger and exhaust fluid from a third heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the second heat exchanger in a counter flow configuration. Furthermore, the heat exchanger system may include a third heat exchanger for receiving working fluid from the second heat exchanger and exhaust fluid from the first heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the third heat exchanger in a parallel flow configuration.

  14. Schizophrenia as segmental progeria

    Science.gov (United States)

    Papanastasiou, Evangelos; Gaughran, Fiona; Smith, Shubulade

    2011-01-01

    Schizophrenia is associated with a variety of physical manifestations (i.e. metabolic, neurological) and despite psychotropic medication being blamed for some of these (in particular obesity and diabetes), there is evidence that schizophrenia itself confers an increased risk of physical disease and early death. The observation that schizophrenia and progeroid syndromes share common clinical features and molecular profiles gives rise to the hypothesis that schizophrenia could be conceptualized as a whole body disorder, namely a segmental progeria. Mammalian cells employ the mechanisms of cellular senescence and apoptosis (programmed cell death) as a means to control inevitable DNA damage and cancer. Exacerbation of those processes is associated with accelerated ageing and schizophrenia and this warrants further investigation into possible underlying biological mechanisms, such as epigenetic control of the genome. PMID:22048679

  15. Probabilistic retinal vessel segmentation

    Science.gov (United States)

    Wu, Chang-Hua; Agam, Gady

    2007-03-01

    Optic fundus assessment is widely used for diagnosing vascular and non-vascular pathology. Inspection of the retinal vasculature may reveal hypertension, diabetes, arteriosclerosis, cardiovascular disease and stroke. Due to various imaging conditions retinal images may be degraded. Consequently, the enhancement of such images and vessels in them is an important task with direct clinical applications. We propose a novel technique for vessel enhancement in retinal images that is capable of enhancing vessel junctions in addition to linear vessel segments. This is an extension of vessel filters we have previously developed for vessel enhancement in thoracic CT scans. The proposed approach is based on probabilistic models which can discern vessels and junctions. Evaluation shows the proposed filter is better than several known techniques and is comparable to the state of the art when evaluated on a standard dataset. A ridge-based vessel tracking process is applied on the enhanced image to demonstrate the effectiveness of the enhancement filter.

  16. Improved Self Fused Check pointing Replication for Handling Multiple Faults in Cloud Computing

    Directory of Open Access Journals (Sweden)

    Sanjay Bansal

    2012-06-01

    Full Text Available The performance of checkpointing replication fault tolerance technique is severely bottlenecks due to handling of number of replicas generated for a large number of nodes to tolerate multiple faults such as multiple failure of nodes, processes etc. In fusion based approach, these checkpointing replicas stored at large number of computing nodes is aggregated into some data structure to handle efficiently through fused data structure. These impose higher overheads of fusing a large numbers of checkpointing replicas. In this paper, a self fused checkpointing replication (SFCR for cloud computing is proposed. All checkpointing replicas assigned to store at a particular node are stored in a self-fused-shared-checkpointing-replicas file already created and located at every node rather than storing as a separate checkpointing element and than fusing. Thus, iteliminates the need of further fusing of the checkpointing replicas stored at different checkpointing replicas storage nodes, as checkpointing replicas assign to store a particular node stored in an already created fuse file at every checkpointing replicas storage node. It improves the performance without affecting the specified fault tolerant capabilities as failure of any node will result in loss of all replicas irrespective of separate checkpointing file or shared checkpointing fused file. Costs to maintain these set of self fused shared files are obviously less than the number of separate replicated files in terms of time and efforts that it takes to create, and update a file. Thus, proposed approach is enhancement of performance without compromising the specified fault tolerancecapability. At the same time when system seems to be prone to many number of faults, some specific self fused shared files consist of important and critical data that can be further replicated to enhance the fault tolerant capability of a group of important and critical nodes or processes at run time. Thus, it also

  17. Automated medical image segmentation techniques

    Directory of Open Access Journals (Sweden)

    Sharma Neeraj

    2010-01-01

    Full Text Available Accurate segmentation of medical images is a key step in contouring during radiotherapy planning. Computed topography (CT and Magnetic resonance (MR imaging are the most widely used radiographic techniques in diagnosis, clinical studies and treatment planning. This review provides details of automated segmentation methods, specifically discussed in the context of CT and MR images. The motive is to discuss the problems encountered in segmentation of CT and MR images, and the relative merits and limitations of methods currently available for segmentation of medical images.

  18. Mesp2: a novel mouse gene expressed in the presegmented mesoderm and essential for segmentation initiation.

    Science.gov (United States)

    Saga, Y; Hata, N; Koseki, H; Taketo, M M

    1997-07-15

    We isolated a novel bHLH protein gene Mesp2 (for mesoderm posterior 2) that cross-hybridizes with Mesp1 expressed in the early mouse mesoderm. Mesp2 is expressed in the rostral presomitic mesoderm, but down-regulated immediately after the formation of the segmented somites. To determine the function of MesP2 protein (MesP2) in somitogenesis, we generated Mesp2-deficient mice by gene targeting. The homozygous Mesp2 (-/-) mice died shortly after birth and had fused vertebral columns and dorsal root ganglia, with impaired sclerotomal polarity. The earliest defect in the homozygous embryos was a lack of segmented somites. Their disruption of the metameric features, altered expression of Mox-1, Pax-1, and Dll1, and lack of expression of Notch1, Notch2, and FGFR1 suggested that MesP2 controls sclerotomal polarity by regulating the signaling systems mediated by notch-delta and FGF, which are essential for segmentation.

  19. Joint Program Management Handbook

    Science.gov (United States)

    1994-12-01

    the Engieermg and Manufacuring Devopment Phase. Nfilestoae HI- Develommen Annros Devopment approval marks a significant step for any program, but it is...to review concept formulaton. Systems Engilneertn As with service programs, systems engineering in joint program management is an essential tool . I...MANAGEMENT HANDBOOK On=e wd Umawtaiutt As discussed in Chapter 7, systems analysis of relationships is a usef tool for joint program managers. The joint

  20. Jointly Poisson processes

    CERN Document Server

    Johnson, D H

    2009-01-01

    What constitutes jointly Poisson processes remains an unresolved issue. This report reviews the current state of the theory and indicates how the accepted but unproven model equals that resulting from the small time-interval limit of jointly Bernoulli processes. One intriguing consequence of these models is that jointly Poisson processes can only be positively correlated as measured by the correlation coefficient defined by cumulants of the probability generating functional.

  1. Failure of cervical arthroplasty in a patient with adjacent segment disease associated with Klippel-Feil syndrome

    Directory of Open Access Journals (Sweden)

    Ioannis D Papanastassiou

    2011-01-01

    Full Text Available Cervical arthroplasty may be justified in patients with Klippel-Feil syndrome (KFS in order to preserve cervical motion. The aim of this paper is to report an arthroplasty failure in a patient with KFS. A 36-year-old woman with KFS underwent two-level arthroplasty for adjacent segment disc degeneration. Anterior migration of the cranial prosthesis was encountered 5 months postoperatively and was successfully revised with anterior cervical fusion. Cervical arthroplasty in an extensively stiff and fused neck is challenging and may lead to catastrophic failure. Although motion preservation is desirable in KFS, the special biomechanical features may hinder arthroplasty. Fusion or hybrid constructs may represent more reasonable options, especially when multiple fused segments are present.

  2. Analysis of a kinetic multi-segment foot model. Part I: Model repeatability and kinematic validity.

    Science.gov (United States)

    Bruening, Dustin A; Cooney, Kevin M; Buczek, Frank L

    2012-04-01

    Kinematic multi-segment foot models are still evolving, but have seen increased use in clinical and research settings. The addition of kinetics may increase knowledge of foot and ankle function as well as influence multi-segment foot model evolution; however, previous kinetic models are too complex for clinical use. In this study we present a three-segment kinetic foot model and thorough evaluation of model performance during normal gait. In this first of two companion papers, model reference frames and joint centers are analyzed for repeatability, joint translations are measured, segment rigidity characterized, and sample joint angles presented. Within-tester and between-tester repeatability were first assessed using 10 healthy pediatric participants, while kinematic parameters were subsequently measured on 17 additional healthy pediatric participants. Repeatability errors were generally low for all sagittal plane measures as well as transverse plane Hindfoot and Forefoot segments (mediansegment rigidity analysis suggested rigid body behavior for the Shank and Hindfoot, with the Forefoot violating the rigid body assumptions in terminal stance/pre-swing. Joint excursions were consistent with previously published studies.

  3. Automatic segmentation of pulmonary segments from volumetric chest CT scans.

    NARCIS (Netherlands)

    Rikxoort, E.M. van; Hoop, B. de; Vorst, S. van de; Prokop, M.; Ginneken, B. van

    2009-01-01

    Automated extraction of pulmonary anatomy provides a foundation for computerized analysis of computed tomography (CT) scans of the chest. A completely automatic method is presented to segment the lungs, lobes and pulmonary segments from volumetric CT chest scans. The method starts with lung segmenta

  4. [Total temporomandibular joint prostheses].

    Science.gov (United States)

    Zwetyenga, N; Amroun, S; Wajszczak, B-L; Moris, V

    2016-09-01

    The temporomandibular joint (TMJ) is probably the most complex human joint. As in all joints, its prosthetic replacement may be indicated in selected cases. Significant advances have been made in the design of TMJ prostheses during the last three decades and the indications have been clarified. The aim of our work was to make an update on the current total TMJ total joint replacement. Indications, contraindications, prosthetic components, advantages, disadvantages, reasons for failure or reoperation, virtual planning and surgical protocol have been exposed. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  5. Subtalar joint arthrodesis.

    Science.gov (United States)

    Lopez, Ramon; Singh, Tarika; Banga, Samantha; Hasan, Nafisa

    2012-01-01

    Isolated subtalar joint arthrodesis has gained popularity more recently. Research has shown that it preserves rearfoot motion, does not increase the risk of arthritis in adjacent joints, and is not an especially complex operative procedure. It decreases the chance of midtarsal joint nonunion and malunion postoperatively. This article takes an in-depth approach to isolated talocalcaneal fusions. Anatomy and biomechanics of the subtalar joint are reviewed. Clinical presentation and radiologic evaluation are discussed. Conservative treatment, operative technique, and postoperative management are included. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. Interdiffusion of Polycarbonate in Fused Deposition Modeling Welds

    Science.gov (United States)

    Seppala, Jonathan; Forster, Aaron; Satija, Sushil; Jones, Ronald; Migler, Kalman

    2015-03-01

    Fused deposition modeling (FDM), a now common and inexpensive additive manufacturing method, produces 3D objects by extruding molten polymer layer-by-layer. Compared to traditional polymer processing methods (injection, vacuum, and blow molding), FDM parts have inferior mechanical properties, surface finish, and dimensional stability. From a polymer processing point of view the polymer-polymer weld between each layer limits the mechanical strength of the final part. Unlike traditional processing methods, where the polymer is uniformly melted and entangled, FDM welds are typically weaker due to the short time available for polymer interdiffusion and entanglement. To emulate the FDM process thin film bilayers of polycarbonate/d-polycarbonate were annealed using scaled times and temperatures accessible in FDM. Shift factors from Time-Temperature Superposition, measured by small amplitude oscillatory shear, were used to calculate reasonable annealing times (min) at temperatures below the actual extrusion temperature. The extent of interdiffusion was then measured using neutron reflectivity. Analogous specimens were prepared to characterize the mechanical properties. FDM build parameters were then related to interdiffusion between welded layers and mechanical properties. Understating the relationship between build parameters, interdiffusion, and mechanical strength will allow FDM users to print stronger parts in an intelligent manner rather than using trial-and-error and build parameter lock-in.

  7. Mechanical analysis of lightweight constructions manufactured with fused deposition modeling

    Science.gov (United States)

    Bagsik, A.; Josupeit, S.; Schoeppner, V.; Klemp, E.

    2014-05-01

    Additive production techniques have the advantage of manufacturing parts without needing a forming tool. One of the most used additive manufacturing processes is "Fused Deposition Modeling" (FDM) which allows the production of prototypes and end-use parts. Due to the manufacture layer by layer, also complex part geometries can be created in one working step. Furthermore, lightweight parts with specific inner core structures can be manufactured in order to achieve good weightrelated strength properties. In this paper the mechanical behavior of lightweight parts manufactured with the 3D production system Fortus 400mc from Stratasys and the material Polyetherimide (PEI) with the trade name Ultem*9085 is analyzed. The test specimens were built up with different inner structures and building directions. Therefore, test specimens with known lightweight core geometries (e.g. corrugated and honeycomb cores) were designed. A four-point bending test was conducted to analyze the strength properties as well as the weight-related strength properties. Additionally the influence of the structure width, the structure wall thickness and the top layer thickness was analyzed using a honeycomb structure.

  8. Plasticized protein for 3D printing by fused deposition modeling

    Science.gov (United States)

    Chaunier, Laurent; Leroy, Eric; Della Valle, Guy; Lourdin, Denis

    2016-10-01

    The developments of Additive Manufacturing (AM) by Fused Deposition Modeling (FDM) now target new 3D printable materials, leading to novel properties like those given by biopolymers such as proteins: degradability, biocompatibility and edibility. Plasticized materials from zein, a storage protein issued from corn, present interesting thermomechanical and rheological properties, possibly matching with AM-FDM specifications. Thus commercial zein plasticized with 20% glycerol has a glass transition temperature (Tg) at about 42°C, after storage at intermediate relative humidity (RH=59%). Its principal mechanical relaxation at Tα ≈ 50°C leads to a drop of the elastic modulus from about 1.1 GPa, at ambient temperature, to 0.6 MPa at Tα+100°C. These values are in the same range as values obtained in the case of standard polymers for AM-FDM processing, as PLA and ABS, although relaxation mechanisms are likely different in these materials. Such results lead to the setting up of zein-based compositions printable by AM-FDM and allow processing bioresorbable printed parts, with designed 3D geometry and structure.

  9. Measuring and Modelling Crowd Flows - Fusing Stationary and Tracking Data

    CERN Document Server

    Treiber, Martin

    2016-01-01

    The two main data categories of vehicular traffic flow, stationary detector data and floating-car data, are also available for many Marathons and other mass-sports events: Loop detectors and other stationary data sources find their counterpart in the RFID tags of the athletes recording the split times at several stations during the race. Additionally, more and more athletes use smart-phone apps generating track data points that are the equivalent of floating-car data. We present a methodology to detect congestions and estimate the location of jam-fronts, the delay times, and the spatio-temporal speed and density distribution of the athlete's crowd flow by fusing these two data sources based on a first-order macroscopic model with triangular fundamental diagram. The method can be used in real-time or for analyzing past events. Using synthetic "ground truth" data generated by simulations with the Intelligent-Driver Model, we show that, in a real-time application, the proposed algorithm is robust and effective w...

  10. PREPARATION OF HIGH THERMAL EXPANSION COEFFICIENT PORCELAINS FUSED TO METALS

    Institute of Scientific and Technical Information of China (English)

    J.P. Yang; J.Q. Wu

    2003-01-01

    Usually the thermal expansion coefficients (TEC) of metals are higher than that of porcelains. In order to match the TECs in the case of coating porcelains on metals, high TEC porcelains are needed. In this research, the high TEC phase leucite(KAlSi2 O6) in the high TEC porcelain was prepared by sol-gel method. The crystal size of leucite made by sol-gel is about 77nm through controlling the process parameters. The process from xerogel to leucite was investigated by means of DSC (differential scanning calorimetry), TG (thermogravimetry), XRD ( X-ray diffraction) and IR(infrared absorption spectrum). Leucite had been detected after the gel was treated at 900°C, this formation temperature is about 250°C lower than that of melting method.The porcelain made from 50% of the leucite powder and 50%o of low fused temperature frit has an average TEC of 19.2× 10-6/° C from room temperature to 450°C, which is much higher than the common porcelains.

  11. Person Tracking System by Fusing Multicues Based on Patches

    Directory of Open Access Journals (Sweden)

    Song Min Jia

    2015-01-01

    Full Text Available A person tracking algorithm by fusing multicues based on patches is proposed to solve the problem of distinguishing person, occlusion, and illumination variations. Kinect is mounted on the robot for providing color images and depth maps. A detector representing a person by using the fusion of multicues based on patches is proposed. The detector divides the person into many patches and then represents each patch by using depth-color histograms and depth-texture histograms. The appearance representation, considering depth, color, and texture information, has powerful discrimination ability to handle the problems of occlusion, illumination changes, and pose variations. Considering the motion of the robot and person, a tracker called motion extended Kalman filter (MEKF is presented to predict the person’s position. The result of the tracker is treated as a candidate sample of the detector, and then the result of the detector is the previous knowledge of the tracker. The detector and tracker supplement each other and improve the tracking performance. To drive the robot towards the given person precisely, a fuzzy based intelligent gear control strategy (FZ-IGS is implemented. Experiments demonstrate that the proposed approach can track a person in a complex environment and have an optimum performance.

  12. Standardizing Quality Assessment of Fused Remotely Sensed Images

    Science.gov (United States)

    Pohl, C.; Moellmann, J.; Fries, K.

    2017-09-01

    The multitude of available operational remote sensing satellites led to the development of many image fusion techniques to provide high spatial, spectral and temporal resolution images. The comparison of different techniques is necessary to obtain an optimized image for the different applications of remote sensing. There are two approaches in assessing image quality: 1. Quantitatively by visual interpretation and 2. Quantitatively using image quality indices. However an objective comparison is difficult due to the fact that a visual assessment is always subject and a quantitative assessment is done by different criteria. Depending on the criteria and indices the result varies. Therefore it is necessary to standardize both processes (qualitative and quantitative assessment) in order to allow an objective image fusion quality evaluation. Various studies have been conducted at the University of Osnabrueck (UOS) to establish a standardized process to objectively compare fused image quality. First established image fusion quality assessment protocols, i.e. Quality with No Reference (QNR) and Khan's protocol, were compared on varies fusion experiments. Second the process of visual quality assessment was structured and standardized with the aim to provide an evaluation protocol. This manuscript reports on the results of the comparison and provides recommendations for future research.

  13. Covalent non-fused tetrathiafulvalene-acceptor systems.

    Science.gov (United States)

    Pop, Flavia; Avarvari, Narcis

    2016-06-28

    Covalent donor-acceptor (D-A) systems have significantly contributed to the development of many organic materials and to molecular electronics. Tetrathiafulvalene (TTF) represents one of the most widely studied donor precursors and has been incorporated into the structure of many D-A derivatives with the objective of obtaining redox control and modulation of the intramolecular charge transfer (ICT), in order to address switchable emissive systems and to take advantage of its propensity to form regular stacks in the solid state. In this review, we focus on the main families of non-fused TTF-acceptors, which are classified according to the nature of the acceptor: nitrogen-containing heterocycles, BODIPY, perylenes and electron poor unsaturated hydrocarbons, as well as radical acceptors. We describe herein the most representative members of each family with a brief mention of their synthesis and a special focus on their D-A characteristics. Special attention is given to ICT and its modulation, fluorescence quenching and switching, photoconductivity, bistability and spin distribution by discussing and comparing spectroscopic and electrochemical features, photophysical properties, solid-state properties and theoretical calculations.

  14. Explosively formed fuse opening switches for multi-joule applications

    Energy Technology Data Exchange (ETDEWEB)

    Goforth, J.H.; Anderson, B.G.; Bartram, D.E. [and others

    1995-08-01

    High explosive pulsed power (HEPP) systems are capable of generating very high energies in magnetic fields. Such stored energy is usually developed on time scales of a few tens or hundreds of microseconds. Many applications require shorter pulses and opening switches provide one way to use the large energy available for faster applications. With current flowing in an inductive circuit, introducing resistance produces voltage that can be used to drive current into a load. For an opening switch with a fast rising resistance, the load current rise time is determined by the R/L time constant of the circuit. A significant fraction of the circuit energy must be dissipated in the process, and in applications where very large energies must be dealt with only a few types of switches can be used. Experiments with high explosive driven opening switches have produced a few switches that can carry tens of MA current, and open on the time scale of one or a few {mu}s. {sup 1} We have specialized in a type of switch that we call an explosively formed fuse (EFF) switch at levels of {approximately}3 TW for 2{mu}s has become routine, and we will describe its characteristics and give data from a number of tests.

  15. Congenitally caused fused labia in the common marmoset (Callithrix jacchus).

    Science.gov (United States)

    Isachenko, E F; Nayudu, P L; Isachenko, V V; Nawroth, F; Michelmann, H W

    2002-12-01

    In this paper, the occurrence of an external genital abnormality in female marmoset monkeys (fused labia) is discussed. This malformation was detected, for the first time, in a group of animals at the German Primate Center (GPC), Goettingen. The malformed vulva was completely sealed except for an opening of 1.5-2.5 mm around the urethra sufficient for urination. Because of this defect the animals were not able to copulate. As a consequence, the affected females were functionally infertile although they had a normal genital tract and a regular cycle. This vulvar abnormality was found in 12 females, offspring of 10 pairs in which either one or both came to the German Primate Center from two genetically related colonies in Munich, Germany, and one colony in Basel, Switzerland. The abnormality appeared to be recessive and inheritable from either parent. In pairs in which both animals were from one of the mentioned colonies, 45% of the female offspring were affected. In pairs where only one partner came from these colonies, 26% of female offspring had the malformation. These results indicate that avoidance of inbreeding, which is frequently performed in primate colonies, may reduce, but not eliminate the expression of abnormalities of genetic origin. Therefore selective breeding is required, and, in colonies where these recessive mutations are widespread, the development of genetic screening tests would be advantageous.

  16. The compaction of fused silica resulting from ion implantation

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, C.M.; Ridgway, M.C. [Australian National Univ., Canberra, ACT (Australia); Leech, P.L. [Telstra Research Laboratories, Clayton, Victoria (Australia)

    1996-12-31

    Ion implantation of fused silica results in compaction and consequently an increase in refractive index. This method of modifying the near-surface region has been shown as a potential means for fabricating single mode channel waveguides. This study has measured the compaction of the implanted regions for Si implantations as a function of dose (2x10{sup 12} - 6x10{sup l6} ions/cm{sup 2}), energy (1-9 MeV) and post-implantation annealing temperature (200-900 degree C). For a given energy, a dose-dependence of the step height (depth of compacted region) is observed for doses less than {approx}10{sup 15} ions/cm{sup 2}. At higher doses the step height saturates. For a given dose, a linear trend is evident for the step height as a function of energy suggesting that the major mechanism for this compaction is electronic stopping. As the annealing temperature increases, the step height gradually decreases from {approx}0.1-0.2 {mu} to -10-20% of the original value. From the annealing data, it is possible to extract an activation energy of 0.08 eV associated with the thermal removal of the compacted region. 4 refs., 4 figs.

  17. FUSE observations of the Blue Compact Dwarf Galaxy Mrk 59

    CERN Document Server

    Thuan, T X; Izotov, Yu I

    2001-01-01

    New FUSE far-UV spectroscopy of the nearby metal-deficient (Zsun/8) cometary Blue Compact Dwarf (BCD) galaxy Markarian (Mrk) 59 is discussed. The data are used to investigate element abundances in its interstellar medium. The H I absorption lines are characterized by narrow cores which are interstellar in origin and by broad wings which are stellar in origin. The mean interstellar H I column density is ~ 7x10E20 cm-2 in Mrk 59. No H2 lines are seen and N(H2) is < 10E15 cm-2 at the 10 sigma level. The lack of diffuse H2 is due to the combined effect of a strong UV radiation field which destroys the H2 molecules and a low metallicity which leads to a scarcity of dust grains necessary for H2 formation. P-Cygni profiles of the S VI 933.4, 944.5 A and O VI 1031.9, 1037.6 A lines are seen, indicating the presence of very hot O stars and a stellar wind terminal velocity of ~ 1000 km/s. By fitting the line profiles with multiple components having each a velocity dispersion b = 7 km/s and spanning a radial velocity...

  18. Road network safety evaluation using Bayesian hierarchical joint model.

    Science.gov (United States)

    Wang, Jie; Huang, Helai

    2016-05-01

    Safety and efficiency are commonly regarded as two significant performance indicators of transportation systems. In practice, road network planning has focused on road capacity and transport efficiency whereas the safety level of a road network has received little attention in the planning stage. This study develops a Bayesian hierarchical joint model for road network safety evaluation to help planners take traffic safety into account when planning a road network. The proposed model establishes relationships between road network risk and micro-level variables related to road entities and traffic volume, as well as socioeconomic, trip generation and network density variables at macro level which are generally used for long term transportation plans. In addition, network spatial correlation between intersections and their connected road segments is also considered in the model. A road network is elaborately selected in order to compare the proposed hierarchical joint model with a previous joint model and a negative binomial model. According to the results of the model comparison, the hierarchical joint model outperforms the joint model and negative binomial model in terms of the goodness-of-fit and predictive performance, which indicates the reasonableness of considering the hierarchical data structure in crash prediction and analysis. Moreover, both random effects at the TAZ level and the spatial correlation between intersections and their adjacent segments are found to be significant, supporting the employment of the hierarchical joint model as an alternative in road-network-level safety modeling as well.

  19. Shape-Memory Properties of Segmented Polymers Containing Aramid Hard Segments and Polycaprolactone Soft Segments

    Directory of Open Access Journals (Sweden)

    Arno Kraft

    2010-06-01

    Full Text Available A series of segmented multiblock copolymers containing aramid hard segments and extended polycaprolactone soft segments (with an Mn of 4,200 or 8,200 g mol–1 was prepared and tested for their shape-memory properties. Chain extenders were essential to raise the hard segment concentration so that an extended rubbery plateau could be observed. Dynamic mechanical thermal analysis provided a useful guide in identifying (i the presence of a rubbery plateau, (ii the flow temperature, and (iii the temperature when samples started to deform irreversibly.

  20. Mechanics of Sheeting Joints

    Science.gov (United States)

    Martel, S. J.

    2015-12-01

    Physical breakdown of rock across a broad scale spectrum involves fracturing. In many areas large fractures develop near the topographic surface, with sheeting joints being among the most impressive. Sheeting joints share many geometric, textural, and kinematic features with other joints (opening-mode fractures) but differ in that they are (a) discernibly curved, (b) open near the topographic surface, and (c) form subparallel to the topographic surface. Where sheeting joints are geologically young, the surface-parallel compressive stresses are typically several MPa or greater. Sheeting joints are best developed beneath domes, ridges, and saddles; they also are reported, albeit rarely, beneath valleys or bowls. A mechanism that accounts for all these associations has been sought for more than a century: neither erosion of overburden nor high lateral compressive stresses alone suffices. Sheeting joints are not accounted for by Mohr-Coulomb shear failure criteria. Principles of linear elastic fracture mechanics, together with the mechanical effect of a curved topographic surface, do provide a basis for understanding sheeting joint growth and the pattern sheeting joints form. Compressive stresses parallel to a singly or doubly convex topographic surface induce a tensile stress perpendicular to the surface at shallow depths; in some cases this alone could overcome the weight of overburden to open sheeting joints. If regional horizontal compressive stresses, augmented by thermal stresses, are an order of magnitude or so greater than a characteristic vertical stress that scales with topographic amplitude, then topographic stress perturbations can cause sheeting joints to open near the top of a ridge. This topographic effect can be augmented by pressure within sheeting joints arising from water, ice, or salt. Water pressure could be particularly important in helping drive sheeting joints downslope beneath valleys. Once sheeting joints have formed, the rock sheets between

  1. Optimally segmented permanent magnet structures

    DEFF Research Database (Denmark)

    Insinga, Andrea Roberto; Bjørk, Rasmus; Smith, Anders

    2016-01-01

    We present an optimization approach which can be employed to calculate the globally optimal segmentation of a two-dimensional magnetic system into uniformly magnetized pieces. For each segment the algorithm calculates the optimal shape and the optimal direction of the remanent flux density vector...

  2. Upper medium segment cooling down

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>The sluggish growth of the passenger car market in top provinces was also reflected in a depression of the upper medium segment. In Jan-Apr, 2008, the top 3 upper medium models accounting for nearly 40% of this segment performed poorly, with the Passat-Lingyu and the Accord decreasing. The Camry also saw a decrease in three top provinces: Guangdong,

  3. Essays in International Market Segmentation

    NARCIS (Netherlands)

    Hofstede, ter F.

    1999-01-01

    The primary objective of this thesis is to develop and validate new methodologies to improve the effectiveness of international segmentation strategies. The current status of international market segmentation research is reviewed in an introductory chapter, which provided a number of methodological

  4. Adaptive Segmentation for Scientific Databases

    NARCIS (Netherlands)

    Ivanova, M.G.; Kersten, M.L.; Nes, N.J.

    2008-01-01

    In this paper we explore database segmentation in the context of a column-store DBMS targeted at a scientific database. We present a novel hardware- and scheme-oblivious segmentation algorithm, which learns and adapts to the workload immediately. The approach taken is to capitalize on (intermediate)

  5. Dermatology case: segmental lichen aureus

    OpenAIRE

    Fernandes, I.; S. Carvalho; Machado, S.; Alves,R.; Selores, M.

    2012-01-01

    ABSTRACT The authors describe a clinical case of a six-year-old boy with history of a segmental brownish maculopapular skin eruption on his left thoracic and lumbar wall, since the last four months. Based on clinical and histological findings he was diagnosed with segmental lichen aureus.

  6. Essays in international market segmentation

    NARCIS (Netherlands)

    Hofstede, ter F.

    1999-01-01

    The primary objective of this thesis is to develop and validate new methodologies to improve the effectiveness of international segmentation strategies. The current status of international market segmentation research is reviewed in an introductory chapter, which provided a number of

  7. Adaptive segmentation for scientific databases

    NARCIS (Netherlands)

    Ivanova, M.; Kersten, M.L.; Nes, N.

    2008-01-01

    In this paper we explore database segmentation in the context of a column-store DBMS targeted at a scientific database. We present a novel hardware- and scheme-oblivious segmentation algorithm, which learns and adapts to the workload immediately. The approach taken is to capitalize on (intermediate)

  8. Market segmentation using perceived constraints

    Science.gov (United States)

    Jinhee Jun; Gerard Kyle; Andrew Mowen

    2008-01-01

    We examined the practical utility of segmenting potential visitors to Cleveland Metroparks using their constraint profiles. Our analysis identified three segments based on their scores on the dimensions of constraints: Other priorities--visitors who scored the highest on 'other priorities' dimension; Highly Constrained--visitors who scored relatively high on...

  9. The Importance of Marketing Segmentation

    Science.gov (United States)

    Martin, Gillian

    2011-01-01

    The rationale behind marketing segmentation is to allow businesses to focus on their consumers' behaviors and purchasing patterns. If done effectively, marketing segmentation allows an organization to achieve its highest return on investment (ROI) in turn for its marketing and sales expenses. If an organization markets its products or services to…

  10. Market Segmentation: An Instructional Module.

    Science.gov (United States)

    Wright, Peter H.

    A concept-based introduction to market segmentation is provided in this instructional module for undergraduate and graduate transportation-related courses. The material can be used in many disciplines including engineering, business, marketing, and technology. The concept of market segmentation is primarily a transportation planning technique by…

  11. Segmentation: Slicing the Urban Pie.

    Science.gov (United States)

    Keim, William A.

    1981-01-01

    Explains market segmentation and defines undifferentiated, concentrated, and differentiated marketing strategies. Describes in detail the marketing planning process at the Metropolitan Community Colleges. Focuses on the development and implementation of an ongoing recruitment program designed for the market segment composed of business employees.…

  12. Adaptive segmentation for scientific databases

    NARCIS (Netherlands)

    Ivanova, M.; Kersten, M.L.; Nes, N.

    2008-01-01

    In this paper we explore database segmentation in the context of a column-store DBMS targeted at a scientific database. We present a novel hardware- and scheme-oblivious segmentation algorithm, which learns and adapts to the workload immediately. The approach taken is to capitalize on (intermediate)

  13. Studies on the key parameters in segmental lining design

    Institute of Scientific and Technical Information of China (English)

    Zhenchang Guan; Tao Deng; Gang Wang; Yujing Jiang

    2015-01-01

    The uniform ring model and the shell-spring model for segmental lining design are reviewed in this article. The former is the most promising means to reflect the real behavior of segmental lining, while the latter is the most popular means in practice due to its simplicity. To understand the relationship and the difference between these two models, both of them are applied to the engineering practice of Fuzhou Metro Line I, where the key parameters used in both models are described and compared. The effective ratio of bending rigidity h reflecting the relative stiffness between segmental lining and surrounding ground and the transfer ratio of bending moment x reflecting the relative stiffness between segment and joint, which are two key parameters used in the uniform ring model, are especially emphasized. The reasonable values for these two key parameters are calibrated by comparing the bending moments calculated from both two models. Through case studies, it is concluded that the effective ratio of bending rigidity h increases significantly with good soil properties, increases slightly with increasing overburden, and decreases slightly with increasing water head. Meanwhile, the transfer ratio of bending moment x seems to only relate to the properties of segmental lining itself and has a minor relation with the ground conditions. These results could facilitate the design practice for Fuzhou Metro Line I, and could also provide some references to other projects with respect to similar scenarios.

  14. Motion-based morphological segmentation of wildlife video

    Science.gov (United States)

    Thomas, Naveen M.; Canagarajah, Nishan

    2005-03-01

    Segmentation of objects in a video sequence is a key stage in most content-based retrieval systems. By further analysing the behaviour of these objects, it is possible to extract semantic information suitable for higher level content analysis. Since interesting content in a video is usually provided by moving objects, motion is a key feature to be used for pre content analysis segmentation. A motion based segmentation algorithm is presented in this paper that is both efficient and robust. The algorithm is also robust to the type of camera motion. The framework presented consists of three stages. These are the motion estimation stage, foreground detection stage and the refinement stage. An iteration of the first two stages, adaptively altering the motion estimation parameters each time, results in a joint segmentation and motion estimation approach that is extremely fast and accurate. Two dimensional histograms are used as a tool to carry out the foreground detection. The last stage uses morphological approaches as well as a prediction of foreground regions in future frames to further refine the segmentation. In this paper, results obtained from traditional approaches are compared with that of the proposed framework in the wildlife domain.

  15. Robotic Joints Support Horses and Humans

    Science.gov (United States)

    2008-01-01

    A rehabilitative device first featured in Spinoff 2003 is not only helping human patients regain the ability to walk, but is now helping our four-legged friends as well. The late James Kerley, a prominent Goddard Space Flight Center researcher, developed cable-compliant mechanisms in the 1980s to enable sounding rocket assemblies and robots to grip or join objects. In cable-compliant joints (CCJs), short segments of cable connect structural elements, allowing for six directions of movement, twisting, alignment, and energy damping. Kerley later worked with Goddard s Wayne Eklund and Allen Crane to incorporate the cable-compliant mechanisms into a walker for human patients to support the pelvis and imitate hip joint movement.

  16. The development of a segment-based musculoskeletal model of the lower limb: introducing FreeBody.

    Science.gov (United States)

    Cleather, Daniel J; Bull, Anthony M J

    2015-06-01

    Traditional approaches to the biomechanical analysis of movement are joint-based; that is the mechanics of the body are described in terms of the forces and moments acting at the joints, and that muscular forces are considered to create moments about the joints. We have recently shown that segment-based approaches, where the mechanics of the body are described by considering the effect of the muscle, ligament and joint contact forces on the segments themselves, can also prove insightful. We have also previously described a simultaneous, optimization-based, musculoskeletal model of the lower limb. However, this prior model incorporates both joint- and segment-based assumptions. The purpose of this study was therefore to develop an entirely segment-based model of the lower limb and to compare its performance to our previous work. The segment-based model was used to estimate the muscle forces found during vertical jumping, which were in turn compared with the muscular activations that have been found in vertical jumping, by using a Geers' metric to quantify the magnitude and phase errors. The segment-based model was shown to have a similar ability to estimate muscle forces as a model based upon our previous work. In the future, we will evaluate the ability of the segment-based model to be used to provide results with clinical relevance, and compare its performance to joint-based approaches. The segment-based model described in this article is publicly available as a GUI-based Matlab® application and in the original source code (at www.msksoftware.org.uk).

  17. Overcurrent protection of transformers. Part 2: Traditional and new fusing philosophies for small and large transformers

    Energy Technology Data Exchange (ETDEWEB)

    Cook, C. J.; Niemira, J. K.

    2003-07-01

    New and traditional fusing philosophies for protecting transformers are discussed. This second in a two-part paper covers selection criteria for a transformer-primary fuse to protect the transformer consistent with industry-accepted through-fault protection curves. Also covered are the principles of coordination as they relate to the proper selection of the primary-side fuse and power fuses and the principles underlying the protection of load-side conductors and cables. The critical nature of secondary fault protection on small three-phase transformers used on industrial, commercial, and institutional power systems, as well as small-to-medium size three-phase power transformers used in utility substations is emphasized, in view of the long lead time and expense involved in replacing these transformers. In contrast, no special protection recommendations are made for small-kVA overhead distribution transformers, since they are not considered likely to experience secondary faults, and the rare faults that do occur will not likely be detected and cleared by the primary fuse. Also of importance is the fact that these transformers are inexpensive and readily available. Overall, large fuse rating, used in combination with a tank-mounted surge arrester is recommended, because it can provide better transformer protection than the smaller fuse ratings traditionally employed. 4 refs., 2 tabs., 4 figs.

  18. Abrupt change point detection of annual maximum precipitation using fused lasso

    Science.gov (United States)

    Jeon, Jong-June; Sung, Jang Hyun; Chung, Eun-Sung

    2016-07-01

    Because the widely used Bayesian change point analysis (BCPA) is generally applied to the normal distribution, it cannot be freely used to the annual maximum precipitations (AMP) in South Korea. Therefore, this study proposed the fused lasso penalty function to detect the change point of AMP which can be generally fitted by using the Generalized Extreme Value (GEV) distribution in South Korea. First, four numerical experiments are conducted to compare the detection performances between BCPA and fused lasso method. As a result, fused lasso shows the superiority of the data generated by GEV distribution having skewness. The fused lasso method is applied to 63 weather stations in South Korea and then 17 stations having any change points from BCPA and the GEV fused lasso are analyzed. Similar to the numerical analyses, the GEV fused lasso method can delicately detect the change point of AMPs. After the change point, the means of AMPs did not go back to the previous. Alternately, BCPA can be stated to find variation points not change points because the means returned to their original values as time progressed. Therefore, it can be concluded that the GEV fused lasso method detects the change points of non-stationary AMPs of South Korea. This study can be extended to more extreme distributions for various meteorological variables.

  19. Structure formation and properties of a copper-aluminum joint produced by ultrasound-assisted explosive welding

    Science.gov (United States)

    Kuz'min, E. V.; Peev, A. P.; Kuz'min, S. V.; Lysak, V. I.

    2017-08-01

    The effect of ultrasound-assisted explosive welding on the structure formation and the properties of copper-aluminum joints is studied. Ultrasound-assisted explosive welding improves the quality of formed copper-aluminum joints, i.e., enhances their strength and significantly reduces the amount of fused metal over the entire weldability range. It is shown that ultrasound-assisted explosive welding can noticeably extend the weldability range of the copper-aluminum pair to obtain equal-in-strength joints with minimum structural heterogeneity in the wide welding range.

  20. MR diagnosis of temporomandibular joint. A study of joint effusion

    Energy Technology Data Exchange (ETDEWEB)

    Kaneda, Takashi; Yamashiro, Mitsuaki; Ozawa, Kaoru; Suzuki, Hiromi; Okada, Hiroyuki; Yamamoto, Hirotsugu [Nihon Univ., Matsudo, Chiba (Japan). School of Dentistry

    1998-03-01

    The purposes of this study were to evaluate the relationship between correlation of MR joint effusion of the temporomandibular joint and disk position, to evaluate the relationship between joint effusion and aging, and to assess the frequency of MR joint effusion of bilateral temporomandibular joints. The temporomandibular joints of 192 patients with clinical symptoms of temporomandibular joint disorders were imaged bilaterally using high field, surface-coil MR imaging. Oblique sagittal and coronal proton density-weighted and T2-weighted images were obtained. Imaging findings of joint effusion were correlated with disk position, aging, and bilateral temporomandibular joints. MR showed effusion in 4% of the joints with normal superior disk position, 36% of the joints with disk displacement with reduction, and 45% of the joints with disk displacement without reduction. There were significant differences in the incidence of joint effusion between normal disk position and anterior disk displacement with or without reduction. Younger patients less than 40 years were significant higher the incidence of joint effusion than those of older patients. A significant association was seen between joint effusion and aging. MR showed effusion in 17% of the unilateral temporomandibular joint, 24% of the bilateral temporomandibular joints. There was no significant difference between unilateral and bilateral case. These results indicated that joint effusion using MR imaging was associated with varied temporomandibular joint pathologic states. (author)

  1. Thoracic costotransverse joint pain patterns: a study in normal volunteers

    Directory of Open Access Journals (Sweden)

    Wainner Robert S

    2008-10-01

    Full Text Available Abstract Background Pain referral patterns of asymptomatic costotransverse joints have not been established. The objective of this study was to determine the pain referral patterns of asymptomatic costotransverse joints via provocative intra-articular injection. Methods Eight asymptomatic male volunteers received a combined total of 21 intra-articular costotransverse joint injections. Fluoroscopic imaging was used to identify and isolate each costotransverse joint and guide placement of a 25 gauge, 2.5 inch spinal needle into the costotransverse joint. Following contrast medium injection, the quality, intensity, and distribution of the resultant pain produced were recorded. Results Of the 21 costotransverse joint injections, 16 (76% were classified as being intra-articular via arthrograms taken at the time of injection, and 14 of these injections produced a pain sensation distinctly different from that of needle placement. Average pain produced was 3.3/10 on a 0–10 verbal pain scale. Pain was described generally as a deep, dull ache, and pressure sensation. Pain patterns were located superficial to the injected joint, with only the right T2 injections showing referred pain 2 segments cranially and caudally. No chest wall, upper extremity or pseudovisceral pains were reported. Conclusion This study provides preliminary data of the pain referral patterns of costotransverse joints. Further research is needed to compare these findings with those elicited from symptomatic subjects.

  2. Creep of timber joints

    NARCIS (Netherlands)

    Van de Kuilen, J.W.G.

    2008-01-01

    A creep analysis has been performed on nailed, toothed-plates and split-ring joints in a varying uncontrolled climate. The load levels varied between 30% and 50% of the average ultimate short term strength of these joints, tested in accordance with ISO 6891. The climate in which the tests were

  3. Acromioclavicular Joint Separations

    Science.gov (United States)

    2013-01-01

    Published online: 16 December 2012 # Springer Science+Business Media New York 2012 Abstract Acromioclavicular (AC) joint separations are common...injuries. The sports most likely to cause AC joint dislocations are football, soccer , hockey, rugby, and skiing, among others [9, 28, 29]. The major cause

  4. The LOFT Ground Segment

    CERN Document Server

    Bozzo, E; Argan, A; Barret, D; Binko, P; Brandt, S; Cavazzuti, E; Courvoisier, T; Herder, J W den; Feroci, M; Ferrigno, C; Giommi, P; Götz, D; Guy, L; Hernanz, M; Zand, J J M in't; Klochkov, D; Kuulkers, E; Motch, C; Lumb, D; Papitto, A; Pittori, C; Rohlfs, R; Santangelo, A; Schmid, C; Schwope, A D; Smith, P J; Webb, N A; Wilms, J; Zane, S

    2014-01-01

    LOFT, the Large Observatory For X-ray Timing, was one of the ESA M3 mission candidates that completed their assessment phase at the end of 2013. LOFT is equipped with two instruments, the Large Area Detector (LAD) and the Wide Field Monitor (WFM). The LAD performs pointed observations of several targets per orbit (~90 minutes), providing roughly ~80 GB of proprietary data per day (the proprietary period will be 12 months). The WFM continuously monitors about 1/3 of the sky at a time and provides data for about ~100 sources a day, resulting in a total of ~20 GB of additional telemetry. The LOFT Burst alert System additionally identifies on-board bright impulsive events (e.g., Gamma-ray Bursts, GRBs) and broadcasts the corresponding position and trigger time to the ground using a dedicated system of ~15 VHF receivers. All WFM data are planned to be made public immediately. In this contribution we summarize the planned organization of the LOFT ground segment (GS), as established in the mission Yellow Book 1 . We...

  5. Evolution of segmented strings

    CERN Document Server

    Gubser, Steven S

    2016-01-01

    I explain how to evolve segmented strings in de Sitter and anti-de Sitter spaces of any dimension in terms of forward-directed null displacements. The evolution is described entirely in terms of discrete hops which do not require a continuum spacetime. Moreover, the evolution rule is purely algebraic, so it can be defined not only on ordinary real de Sitter and anti-de Sitter, but also on the rational points of the quadratic equations that define these spaces. For three-dimensional anti-de Sitter space, a simpler evolution rule is possible that descends from the Wess-Zumino-Witten equations of motion. In this case, one may replace three-dimensional anti-de Sitter space by a non-compact discrete subgroup of SL(2,R) whose structure is related to the Pell equation. A discrete version of the BTZ black hole can be constructed as a quotient of this subgroup. This discrete black hole avoids the firewall paradox by a curious mechanism: even for large black holes, there are no points inside the horizon until one reach...

  6. Segment Based Camera Calibration

    Institute of Scientific and Technical Information of China (English)

    马颂德; 魏国庆; 等

    1993-01-01

    The basic idea of calibrating a camera system in previous approaches is to determine camera parmeters by using a set of known 3D points as calibration reference.In this paper,we present a method of camera calibration in whih camera parameters are determined by a set of 3D lines.A set of constraints is derived on camea parameters in terms of perspective line mapping.Form these constraints,the same perspective transformation matrix as that for point mapping can be computed linearly.The minimum number of calibration lines is 6.This result generalizes that of Liu,Huang and Faugeras[12] for camera location determination in which at least 8 line correspondences are required for linear computation of camera location.Since line segments in an image can be located easily and more accurately than points,the use of lines as calibration reference tends to ease the computation in inage preprocessing and to improve calibration accuracy.Experimental results on the calibration along with stereo reconstruction are reported.

  7. Online Joint Trajectory Generation of Human-like Biped Walking

    Directory of Open Access Journals (Sweden)

    Jong-Wook Kim

    2014-02-01

    Full Text Available Biped walking has long been studied in the area of gait analysis and robotic locomotion. The goal of this paper is to establish a systematic methodology for human-like natural walking by fusing the measured human joint data and optimal pattern generation techniques based on a full-body humanoid model. To this end, this paper proposes an adaptive two-stage gait pattern by which the step length and walking velocity can be changed with two scaling factors. In addition, to cope with the situations involving passing over a small obstacle, the joint trajectories of the swing foot can be adjusted with a novel concept of differential angle trajectory using a reliable optimization method, viz. particle swarm optimization. The feasibility of the proposed walking scheme is validated by walking experiments with the robot platform DARwIn-OP.

  8. Local label learning (L3) for multi-atlas based segmentation

    Science.gov (United States)

    Hao, Yongfu; Liu, Jieqiong; Duan, Yunyun; Zhang, Xinqing; Yu, Chunshui; Jiang, Tianzi; Fan, Yong

    2012-02-01

    For subcortical structure segmentation, multi-atlas based segmentation methods have attracted great interest due to their competitive performance. Under this framework, using deformation fields generated for registering atlas images to the target image, labels of the atlases are first propagated to the target image space and further fused somehow to get the target segmentation. Many label fusion strategies have been proposed and most of them adopt predefined weighting models which are not necessarily optimal. In this paper, we propose a local label learning (L3) strategy to estimate the target image's label using statistical machine learning techniques. Specifically, we use Support Vector Machine (SVM) to learn a classifier for each of the target image voxels using its neighboring voxels in the atlases as a training dataset. Each training sample has dozens of image features extracted around its neighborhood and these features are optimally combined by the SVM learning method to classify the target voxel. The key contribution of this method is the development of a locally specific classifier for each target voxel based on informative texture features. The validation experiment on 57 MR images has demonstrated that our method generates segmentation results of hippocampal with a dice overlap of 0.908+/-0.023 to manual segmentations, statistically significantly better than state-of-the-art segmentation algorithms.

  9. Automated Target Planning for FUSE Using the SOVA Algorithm

    Science.gov (United States)

    Heatwole, Scott; Lanzi, R. James; Civeit, Thomas; Calvani, Humberto; Kruk, Jeffrey W.; Suchkov, Anatoly

    2007-01-01

    The SOVA algorithm was originally developed under the Resilient Systems and Operations Project of the Engineering for Complex Systems Program from NASA s Aerospace Technology Enterprise as a conceptual framework to support real-time autonomous system mission and contingency management. The algorithm and its software implementation were formulated for generic application to autonomous flight vehicle systems, and its efficacy was demonstrated by simulation within the problem domain of Unmanned Aerial Vehicle autonomous flight management. The approach itself is based upon the precept that autonomous decision making for a very complex system can be made tractable by distillation of the system state to a manageable set of strategic objectives (e.g. maintain power margin, maintain mission timeline, and et cetera), which if attended to, will result in a favorable outcome. From any given starting point, the attainability of the end-states resulting from a set of candidate decisions is assessed by propagating a system model forward in time while qualitatively mapping simulated states into margins on strategic objectives using fuzzy inference systems. The expected return value of each candidate decision is evaluated as the product of the assigned value of the end-state with the assessed attainability of the end-state. The candidate decision yielding the highest expected return value is selected for implementation; thus, the approach provides a software framework for intelligent autonomous risk management. The name adopted for the technique incorporates its essential elements: Strategic Objective Valuation and Attainability (SOVA). Maximum value of the approach is realized for systems where human intervention is unavailable in the timeframe within which critical control decisions must be made. The Far Ultraviolet Spectroscopic Explorer (FUSE) satellite, launched in 1999, has been collecting science data for eight years.[1] At its beginning of life, FUSE had six gyros in two

  10. Strategies for joint appointments.

    Science.gov (United States)

    Royle, J; Crooks, D L

    1985-01-01

    The structure and policies governing joint appointments discussed above, are developed primarily through cooperation and collaboration between nursing service and education institutions. The joint appointee participates in the process of negotiation of salary, benefits and role responsibilities and exploration of the implications of the appointment for personal career development. Implementation and maintenance of the appointment requires the collaborative efforts of the joint appointee with both contracting agencies. Factors influencing the functioning of joint appointees have been identified and strategies to facilitate functioning presented. The joint appointee must be independent in thought and action yet adaptable to work within the boundaries of two social systems with differing values and expectations. Nursing management, peers and students can provide the support needed to overcome the frustrations and to achieve the rewards inherent in successful implementation of an exciting and innovative role.

  11. The design and synthesis of fused thiophenes and their applications in organic field-effect transistors

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Fused thiophenes refer to oligothienoacenes in which several thiophenes are coupled together via twoor multi-positions and their derivatives. The synthesized organic semiconductors based on fused thiophenes exhibit excellent field effect properties due to their efficient intermolecular S…S interactions and π…π stacking. The performances of organic field-effect transistors (OFETs) depend not only on the materials but also on the devices. Such factors which influence the device performances as device structures, fabrication technologies and interface engineering are extensively investigated based on the fused thiophenes. Searching for new organic semiconductors and improving the device fabrication technologies are two major issues in the development of OFETs.

  12. The chemistry and biological activity of heterocycle-fused quinolinone derivatives: A review.

    Science.gov (United States)

    Shiro, Tomoya; Fukaya, Takayuki; Tobe, Masanori

    2015-06-05

    Among all heterocycles, the heterocycle-fused quinolinone scaffold is one of the privileged structures in drug discovery as heterocycle-fused quinolinone derivatives exhibit various biological activities allowing them to act as anti-inflammatory, anticancer, antidiabetic, and antipsychotic agents. This wide spectrum of biological activity has attracted a great deal of attention in the field of medicinal chemistry. In this review, we provide a comprehensive description of the biological and pharmacological properties of various heterocycle-fused quinolinone scaffolds and discuss the synthetic methods of some of their derivatives.

  13. Synthesis and Thermal Behavior of a Fused, Tricyclic 1,2,3,4-Tetrazine Ring System.

    Science.gov (United States)

    Chavez, David E; Bottaro, Jeffery C; Petrie, Mark; Parrish, Damon A

    2015-10-26

    This study presents the synthesis and characterization of a fused, tricyclic 1,2,3,4-tetrazine ring system. The molecule is synthesized in a three-step process from 5,5'-dinitro-bis,1,2,4-triazole via a di-N-amino compound. Oxidation to form the azo-coupled fused tricyclic 1,2,3,4-tetrazine is achieved using tert-butyl hypochlorite as the oxidant. The di-N-amino compound and the desired fused tricyclic 1,2,3,4-triazine display interesting thermal behavior and are predicted to be high-performance energetic materials.

  14. Arsenic Sulfide Nanowire Formation on Fused Quartz Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Olmstead, J.; Riley, B.J.; Johnson, B.R.; Sundaram, S.K.

    2005-01-01

    Arsenic sulfide (AsxSy) nanowires were synthesized by an evaporation-condensation process in evacuated fused quartz ampoules. During the deposition process, a thin, colored film of AsxSy was deposited along the upper, cooler portion of the ampoule. The ampoule was sectioned and the deposited film analyzed using scanning electron microscopy (SEM) to characterize and semi-quantitatively evaluate the microstructural features of the deposited film. A variety of microstructures were observed that ranged from a continuous thin film (warmer portion of the ampoule), to isolated micron- and nano-scale droplets (in the intermediate portion), as well as nanowires (colder portion of the ampoule). Experiments were conducted to evaluate the effects of ampoule cleaning methods (e.g. modify surface chemistry) and quantity of source material on nanowire formation. The evolution of these microstructures in the thin film was determined to be a function of initial pressure, substrate temperature, substrate surface treatment, and initial volume of As2S3 glass. In a set of two experiments where the initial pressure, substrate thermal gradient, and surface treatment were the same, the initial quantity of As2S3 glass per internal ampoule volume was doubled from one test to the other. The results showed that AsxSy nanowires were only formed in the test with the greater initial quantity of As2S3 per internal ampoule volume. The growth data for variation in diameter (e.g. nanowire or droplet) as a function of substrate temperature was fit to an exponential trendline with the form y = Aekx, where y is the structure diameter, A = 1.25×10-3, k = 3.96×10-2, and x is the temperature with correlation coefficient, R2 = 0.979, indicating a thermally-activated process.

  15. Sometimes spelling is easier than phonemic segmentation

    NARCIS (Netherlands)

    Bon, W.H.J. van; Duighuisen, H.C.M.

    1995-01-01

    Poor spellers from the Netherlands segmented and spelled the same words on different occasions. If they base their spellings on the segmentations that they produce in the segmentation task, the correlation between segmentation and spelling scores should be high, and segmentation should not be more d

  16. A Segmental Framework for Representing Signs Phonetically

    Science.gov (United States)

    Johnson, Robert E.; Liddell, Scott K.

    2011-01-01

    The arguments for dividing the signing stream in signed languages into sequences of phonetic segments are compelling. The visual records of instances of actually occurring signs provide evidence of two basic types of segments: postural segments and trans-forming segments. Postural segments specify an alignment of articulatory features, both manual…

  17. Experimental strain measurements on large diameter mitered pipe joints

    Energy Technology Data Exchange (ETDEWEB)

    Feier, Ioan I.; Leis, Brian N.; Zhu, Xian-Kui [Battelle Memorial Institute, Columbus, OH (United States); Stonesifer, Randall B. [Computational Mechanics Inc., Julian, PA (United States); Stavrakas, John S. [National Grid, Waltham, MA (United States); Eletto, Daniel D. [National Grid, Hicksville, NY (United States)

    2010-07-01

    Nowadays, small directional changes in a piping system are achieved by using cold field bent sections however, in the past, miter joints were used and so some pipelines still have such joints. The aim of this study was to determine the stress amplification due to miters in gas transmission pipelines. Experiments were carried out on X42 pipeline steel miter joints, 3 were taken from the Clove Lakes segment of the National grid system and 3 were manufactured for the test, all miter angles were between 0 and 8 degrees of total pipeline direction change; strain gauges were used to measure hoop and axial strains. Results showed that the stress increase due to miter joints increases linearly with the miter angle; in addition it was found that miters on the studied pipeline did not compromise its integrity. This study provided a good understanding of miter induced stress but results are limited to pipe with r/t values of 30.

  18. Lateral atlantoaxial joint arthrography in atlantoaxial rotatory fixation.

    Science.gov (United States)

    Hosono, Noboru; Yonenobu, Kazuo; Tada, Koichi; Yoshikawa, Hideki

    2003-04-01

    There has been much debate about the pathogenesis of atlantoaxial rotatory fixation. Intraarticular abnormality has not been well documented thus far. This is the first case of chronic atlantoaxial rotatory fixation in which atlantoaxial joints were examined by consecutive arthrography. A 7-year-old girl was diagnosed with atlantoaxial rotatory fixation on a three-dimensional CT scan. Arthrography of the lateral atlantoaxial joints indicated a rupture of the joint capsule on the dislocated side at first, followed by a successful repair after 5 weeks' immobilization with a halo apparatus. Because torticollis recurred after taking off the halo vest, we performed surgery in which severe adhesion of the cartilage surface of facet joint was noted on the undislocated side and release of the adhesion was needed to mobilize the atlas. Atlantoaxial arthrodesis by screw fixation facilitated a solid fusion of the segment.

  19. Ankle and midfoot kinetics during normal gait: a multi-segment approach.

    Science.gov (United States)

    Dixon, Philippe C; Böhm, Harald; Döderlein, Leonhard

    2012-04-01

    Multi-segment foot models are increasingly being used to evaluate intra and inter-segment foot kinematics such as the motion between the hindfoot/tibia (ankle) and the forefoot/hindfoot (midfoot) during walking. However, kinetic analysis have been mainly restricted to one-segment foot models and could be improved by considering a multi-segment approach. Therefore, the aims of this study were to (1) implement a kinetic analysis of the ankle and theoretical midfoot joints using the existing Oxford Foot Model (OFM) through a standard inverse dynamics approach using only marker, force plate and anthropometric data and (2) to compare OFM ankle joint kinetics to those output by the one-segment foot plugin-gait model (PIG). 10 healthy adolescents fitted with both the OFM and PIG markers performed barefoot comfortable speed walking trials over an instrumented walkway. The maximum ankle power generation was significantly reduced by approximately 40% through OFM calculations compared to PIG estimates (psegment foot models overestimate ankle power, and may also overestimate the contribution of the triceps surae. A multi-segment approach may help quantify the important contribution of the midfoot ligaments and musculature to power generation. We therefore recommend the use of multi-segment foot models to estimate ankle and midfoot kinetics, especially when surgical decision-making is based on the results of three-dimensional gait analysis.

  20. Multiatlas segmentation as nonparametric regression.

    Science.gov (United States)

    Awate, Suyash P; Whitaker, Ross T

    2014-09-01

    This paper proposes a novel theoretical framework to model and analyze the statistical characteristics of a wide range of segmentation methods that incorporate a database of label maps or atlases; such methods are termed as label fusion or multiatlas segmentation. We model these multiatlas segmentation problems as nonparametric regression problems in the high-dimensional space of image patches. We analyze the nonparametric estimator's convergence behavior that characterizes expected segmentation error as a function of the size of the multiatlas database. We show that this error has an analytic form involving several parameters that are fundamental to the specific segmentation problem (determined by the chosen anatomical structure, imaging modality, registration algorithm, and label-fusion algorithm). We describe how to estimate these parameters and show that several human anatomical structures exhibit the trends modeled analytically. We use these parameter estimates to optimize the regression estimator. We show that the expected error for large database sizes is well predicted by models learned on small databases. Thus, a few expert segmentations can help predict the database sizes required to keep the expected error below a specified tolerance level. Such cost-benefit analysis is crucial for deploying clinical multiatlas segmentation systems.

  1. Automatic Cell Segmentation Using a Shape-Classification Model in Immunohistochemically Stained Cytological Images

    Science.gov (United States)

    Shah, Shishir

    This paper presents a segmentation method for detecting cells in immunohistochemically stained cytological images. A two-phase approach to segmentation is used where an unsupervised clustering approach coupled with cluster merging based on a fitness function is used as the first phase to obtain a first approximation of the cell locations. A joint segmentation-classification approach incorporating ellipse as a shape model is used as the second phase to detect the final cell contour. The segmentation model estimates a multivariate density function of low-level image features from training samples and uses it as a measure of how likely each image pixel is to be a cell. This estimate is constrained by the zero level set, which is obtained as a solution to an implicit representation of an ellipse. Results of segmentation are presented and compared to ground truth measurements.

  2. Minimally Invasive Sacroiliac Joint Fusion: One-Year Outcomes in 40 Patients

    Directory of Open Access Journals (Sweden)

    Donald Sachs

    2013-01-01

    Full Text Available Background. SI joint pain is difficult to diagnose due to overlapping symptoms of the lumbar spine, and until recently, treatment options have been limited. The purpose of this retrospective study is to report on the safety and effectiveness of MIS SI joint arthrodesis using a series of triangular, porous plasma coated implants in patients refractory to conservative care. Methods. We report on the first 40 consecutive patients with one-year follow-up data that underwent MIS SI joint fusion with the iFuse Implant System (SI-BONE, Inc., San Jose, CA by a single surgeon. Medical charts were reviewed for demographics, perioperative metrics, complications, pain scores, and satisfaction. Results. Mean age was 58 years (range 30–81 and 75% of patients were female. Postoperative complications were minimal and included transient trochanteric bursitis (5%, facet joint pain (20%, and new low back pain (2.5%. There were no reoperations at one year. Mean pain score improved from 8.7 (1.5 SD at baseline to 0.9 (1.6 at 12 months, a 7.8-point improvement (P<.001. Patient satisfaction was very high. Conclusions. The results of this case series reveal that MIS SI joint fusion using the iFuse Implant System is a safe and effective treatment option in carefully selected patients.

  3. Iris Pattern Segmentation using Automatic Segmentation and Window Technique

    OpenAIRE

    Swati Pandey; Prof. Rajeev Gupta

    2013-01-01

    A Biometric system is an automatic identification of an individual based on a unique feature or characteristic. Iris recognition has great advantage such as variability, stability and security. In thispaper, use the two methods for iris segmentation -An automatic segmentation method and Window method. Window method is a novel approach which comprises two steps first finds pupils' center andthen two radial coefficients because sometime pupil is not perfect circle. The second step extract the i...

  4. Principles of Video Segmentation Scenarios

    Directory of Open Access Journals (Sweden)

    M. R. KHAMMAR

    2013-05-01

    Full Text Available Video segmentation is the first step toward automatic video processing such as browsing, retrieval, and indexing. Many algorithms and techniques have been proposed a few years ago. They can cover the topic of video segmentation from different angles and it is beneficial to review the most important properties of them in brief in order to clarify the subject and find out the latest challenges and drawbacks. In this paper, the important parameters which are involved in video segmentation are discussed and video shot detection systems are compared together.

  5. Multiple Segmentation of Image Stacks

    DEFF Research Database (Denmark)

    Smets, Jonathan; Jaeger, Manfred

    2014-01-01

    We propose a method for the simultaneous construction of multiple image segmentations by combining a recently proposed “convolution of mixtures of Gaussians” model with a multi-layer hidden Markov random field structure. The resulting method constructs for a single image several, alternative...... segmentations that capture different structural elements of the image. We also apply the method to collections of images with identical pixel dimensions, which we call image stacks. Here it turns out that the method is able to both identify groups of similar images in the stack, and to provide segmentations...

  6. Mitigation of organic laser damage precursors from chemical processing of fused silica.

    Science.gov (United States)

    Baxamusa, S; Miller, P E; Wong, L; Steele, R; Shen, N; Bude, J

    2014-12-01

    Increases in the laser damage threshold of fused silica have been driven by the successive elimination of near-surface damage precursors such as polishing residue, fractures, and inorganic salts. In this work, we show that trace impurities in ultrapure water used to process fused silica optics may be responsible for the formation of carbonaceous deposits. We use surrogate materials to show that organic compounds precipitated onto fused silica surfaces form discrete damage precursors. Following a standard etching process, solvent-free oxidative decomposition using oxygen plasma or high-temperature thermal treatments in air reduced the total density of damage precursors to as low as inorganic compounds are more likely to cause damage when they are tightly adhered to a surface, which may explain why high-temperature thermal treatments have been historically unsuccessful at removing extrinsic damage precursors from fused silica.

  7. Study on the Sensitivity of Landmine Electrical Fuse Circuit Under the Interference of Natural Electromagnetic Pulse

    Science.gov (United States)

    Qin, Dechun

    Landmine electrical fuse circuits on the battlefield will be interfered by natural electromagnetic pulse such as electrostatic discharge and lightning, which will undermine the circuit performance and trigger the early burst or mistaken burst of the landmines. In this paper, numerically simulation analysis is conducted on the electrostatic and lightning effects received by the landmine fuse circuit by means of building simulation model of the fuse circuit and analyzing the electric and magnetic field changes of the observation The mechanism of the influence of electrostatic discharge and lightning on the sensitivity of the fuse circuit is explored. The conclusion is that electrostatic effect cause the mistaken burst of the landmines by enabling the interference voltage to reach the components turn-on threshold and cause the circuit malfunction, and lighting effect by long period accumulation of energy.

  8. Effect of Scanning Beam Profile to Fabricate Fused Fiber Tapers by CO_2 Laser Irradiation Method

    Institute of Scientific and Technical Information of China (English)

    Bayle; Fabien; Luo; Aiping; Marin; Emmanuel; Meunier; Jean-Pierre

    2003-01-01

    Beam uniformity is a crucial building block of CO2 experiments aimed at fusing and stretching optical fibers in a lossless manner. When the irradiation beam is expanded through a galvanometer mirror, ways to achieve beam uniformity are investigated.

  9. Effect of Scanning Beam Profile to Fabricate Fused Fiber Tapers by CO2 Laser Irradiation Method

    Institute of Scientific and Technical Information of China (English)

    Bayle Fabien; Luo Aiping; Marin Emmanuel; Meunier Jean-Pierre

    2003-01-01

    Beam uniformity is a crucial building block of CO2 experiments aimed at fusing and stretching optical fibers in a lossless manner. When the irradiation beam is expanded through a galvanometer mirror, ways to achieve beam uniformity are investigated.

  10. Synthesis of fused indazole ring systems and application to nigeglanine hydrobromide.

    Science.gov (United States)

    Sather, Aaron C; Berryman, Orion B; Rebek, Julius

    2012-03-16

    The single-step synthesis of fused tricyclic pyridazino[1,2-a]indazolium ring systems is described. Structural details revealed by crystallography explain the unexpected reactivity. The method is applied to the gram scale synthesis of nigeglanine hydrobromide.

  11. A quinoxaline-fused tetrathiafulvalene-based sensitizer for efficient dye-sensitized solar cells.

    Science.gov (United States)

    Amacher, Anneliese; Yi, Chenyi; Yang, Jiabao; Bircher, Martin Peter; Fu, Yongchun; Cascella, Michele; Grätzel, Michael; Decurtins, Silvio; Liu, Shi-Xia

    2014-06-21

    A new quinoxaline-fused tetrathiafulvalene-based sensitizer has been prepared and characterized. The resulting power conversion efficiency of 6.47% represents the best performance to date for tetrathiafulvalene-sensitized solar cells.

  12. Effects of humidity on the interaction between a fused silica test mass and an electrostatic drive

    Energy Technology Data Exchange (ETDEWEB)

    Koptsov, D.V., E-mail: kopcov@physics.msu.ru; Prokhorov, L.G.; Mitrofanov, V.P.

    2015-10-23

    Interaction of a fused silica test mass with electric field of an electrostatic drive with interdigitated electrodes and influence of ambient air humidity on this interaction are investigated. The key element of the experimental setup is the fused silica torsional oscillator. Time dependent increase of the torque acting on the oscillator's plate after application of DC voltage to the drive is demonstrated. The torque relaxation is presumably caused by the redistribution of electric charges on the fused silica plate. The numerical model has been developed to compute the time evolution of the plate's surface charge distribution and the corresponding torque. - Highlights: • Interaction between a fused silica plate and an electrostatic drive was investigated. • The interaction force is time and relative humidity dependent. • Numerical model of the interaction was developed. • Charge redistribution is shown to be the cause of the interaction force evolution.

  13. Bionic Control of Cheetah Bounding with a Segmented Spine

    Directory of Open Access Journals (Sweden)

    Chunlei Wang

    2016-01-01

    Full Text Available A cheetah model is built to mimic real cheetah and its mechanical and dimensional parameters are derived from the real cheetah. In particular, two joints in spine and four joints in a leg are used to realize the motion of segmented spine and segmented legs which are the key properties of the cheetah bounding. For actuating and stabilizing the bounding gait of cheetah, we present a bioinspired controller based on the state-machine. The controller mainly mimics the function of the cerebellum to plan the locomotion and keep the body balance. The haptic sensor and proprioception system are used to detect the trigger of the phase transition. Besides, the vestibular modulation could perceive the pitching angle of the trunk. At last, the cerebellum acts as the CPU to operate the information from the biological sensors. In addition, the calculated results are transmitted to the low-level controller to actuate and stabilize the cheetah bounding. Moreover, the delay feedback control method is employed to plan the motion of the leg joints to stabilize the pitching motion of trunk with the stability criterion. Finally, the cyclic cheetah bounding with biological properties is realized. Meanwhile, the stability and dynamic properties of the cheetah bounding gait are analyzed elaborately.

  14. Bionic Control of Cheetah Bounding with a Segmented Spine.

    Science.gov (United States)

    Wang, Chunlei; Wang, Shigang

    2016-01-01

    A cheetah model is built to mimic real cheetah and its mechanical and dimensional parameters are derived from the real cheetah. In particular, two joints in spine and four joints in a leg are used to realize the motion of segmented spine and segmented legs which are the key properties of the cheetah bounding. For actuating and stabilizing the bounding gait of cheetah, we present a bioinspired controller based on the state-machine. The controller mainly mimics the function of the cerebellum to plan the locomotion and keep the body balance. The haptic sensor and proprioception system are used to detect the trigger of the phase transition. Besides, the vestibular modulation could perceive the pitching angle of the trunk. At last, the cerebellum acts as the CPU to operate the information from the biological sensors. In addition, the calculated results are transmitted to the low-level controller to actuate and stabilize the cheetah bounding. Moreover, the delay feedback control method is employed to plan the motion of the leg joints to stabilize the pitching motion of trunk with the stability criterion. Finally, the cyclic cheetah bounding with biological properties is realized. Meanwhile, the stability and dynamic properties of the cheetah bounding gait are analyzed elaborately.

  15. Joint Robotics Program

    Science.gov (United States)

    2008-04-23

    Åèìáëáíáçå= oÉëÉ~êÅÜ=póãéçëáìã= JOINT ROBOTICS PROGRAM Published: 23 April 2008 by Joel Brown and Paul Varian 5th Annual Acquisition Research...3. DATES COVERED 00-00-2008 to 00-00-2008 4. TITLE AND SUBTITLE Joint Robotics Program 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM...ëóåÉêÖó=Ñçê=áåÑçêãÉÇ=ÅÜ~åÖÉ=======- 464 - = = Joint Robotics Program Presenter: Joel Brown, Defense Acquisition University Author: Paul Varian

  16. Total ankle joint replacement.

    Science.gov (United States)

    2016-02-01

    Ankle arthritis results in a stiff and painful ankle and can be a major cause of disability. For people with end-stage ankle arthritis, arthrodesis (ankle fusion) is effective at reducing pain in the shorter term, but results in a fixed joint, and over time the loss of mobility places stress on other joints in the foot that may lead to arthritis, pain and dysfunction. Another option is to perform a total ankle joint replacement, with the aim of giving the patient a mobile and pain-free ankle. In this article we review the efficacy of this procedure, including how it compares to ankle arthrodesis, and consider the indications and complications.

  17. Joints in steel buildings

    Directory of Open Access Journals (Sweden)

    Gabriel F. Valencia Clement

    2010-04-01

    Full Text Available Masonry and steel components used in constructing buildings are in a constant state of motion. Volumetric changes are produced by temperature variation and deformation resulting from static or dynamic loading and in some materials, such as masonry, due to moisture content. This article addresses means of determining when expansion and seismic joints are required and how to proportion and design appropriate joints, specifically in steel buildings. It does not cover the study of expansion joints in concrete structures, in masonry construction or in non-structural (architectural elements.

  18. N–O Cleavage reactions of heterobicycloalkene-fused 2-isoxazolines

    Directory of Open Access Journals (Sweden)

    Jaipal R. Nagireddy

    2014-09-01

    Full Text Available Transition metal-mediated N–O bond cleavage reactions of heterobicycloalkene-fused 3-methyl-2-isoxazolines were investigated. Optimal cleavage conditions were found with Raney nickel/AlCl3 mediation in aqueous methanol. The reaction provided a diverse collection of novel heterobicycle-fused β-hydroxyketones with good to excellent yields (66–95% and without the need for chromatographic purification.

  19. Search for stress dependence in the internal friction of fused silica

    Energy Technology Data Exchange (ETDEWEB)

    Willems, Phil; Lamb, Corinne; Heptonstall, Alastair; Hough, Jim

    2003-12-01

    The quality factor (Q) of the vertical bounce mode of a fused silica fiber pendulum is measured at high and low stresses. The internal friction of fused silica fibers is found to be independent of stress from 12.8 to 213 MPa at a level of 1.6x10{sup -8}. Comparison with Q's of fiber bending modes is consistent with losses concentrated in the surface of the fiber.

  20. Search for stress dependence in the internal friction of fused silica

    Science.gov (United States)

    Willems, Phil; Lamb, Corinne; Heptonstall, Alastair; Hough, Jim

    2003-12-01

    The quality factor ( Q) of the vertical bounce mode of a fused silica fiber pendulum is measured at high and low stresses. The internal friction of fused silica fibers is found to be independent of stress from 12.8 to 213 MPa at a level of 1.6×10 -8. Comparison with Q's of fiber bending modes is consistent with losses concentrated in the surface of the fiber.