scholarly journals Potentialities of infrared thermography to assess damage in bonding between concrete and GFRP

2015 ◽  
Vol 8 (3) ◽  
pp. 296-322 ◽  
Author(s):  
M. M. CALDEIRA ◽  
I. J. PADARATZ
Keyword(s):  
Infrared Thermography ◽  
Incandescent Lamp ◽  
Measured Temperature ◽  
Reinforced Polymer ◽  
Glass Fiber Reinforced ◽  
Externally Bonded ◽  
Group 2 ◽  
Different Diameters ◽  
Two Stages ◽  
Group 1

This paper demonstrates the application of the active infrared thermography to detect damage in bonding between concrete and glass fiber reinforced polymer (GFRP). Specimens of concrete and mortar with GFRP externally bonded were prepared and at their interfaces were inserted polystyrene discs to simulate damages. The samples were divided into two groups. In group 1, one sample was correctly bonded by a GFRP plate to the concrete, but in the other three were inserted polystyrene discs which had different diameters to simulate damages in bonding. In group 2, all of the samples contained identical polystyrene discs at their interfaces, but the total thickness of each specimen was different, because the objective was to evaluate the ability of the camera to capture the simulated damage in depth. The experimental procedure was divided into two stages. In the first stage, four types of heating were used to heat samples of group 1: incandescent lamp, kiln, blended lamp and fan heater. Thus, it was possible to detect the damage and to observe its format and length. It was noticed that the infrared images are different depending on the heat source incident on the specimen. Therefore, group 2 was tested only for the more efficient heating (incandescent lamp). In the second stage, the infrared equipment was tested. Some of the parameters that must be inserted in the camera were varied in order to understand their influence on image formation. The results show the effectiveness of infrared thermography to assess adherence in GFRP/concrete interface. In the present work, the best results were obtained when the image is captured towards GFRP/concrete and using incandescent lamp. It was observed that the image and measured temperature suffer significant distortion when a false value was inserted for the parameter emissivity.

Attitude of the Canine in Secondary Bone-Grafted and Nongrafted Patients with Cleft Lip and Palate

2005 ◽  
Vol 42 (6) ◽  
pp. 679-686 ◽  
Author(s):  
Enkhtuvshin Gereltzul ◽  
Yoshiyuki Baba ◽  
Kimie Ohyama
Keyword(s):  
Cleft Lip ◽  
Cleft Lip And Palate ◽  
Panoramic Radiography ◽  
Control Groups ◽  
Significant Difference ◽  
Before And After ◽  
Group 2 ◽  
Two Stages ◽  
And Control ◽  
Group 1

Objective To investigate the eruption pattern of the cleft-side canine regarding its pre-eruption position relative to the cleft in bone-grafted (BG) and nongrafted (NonBG) patients with cleft lip and palate. Methods Fifty-three patients with cleft lip and palate (21 BG, 32 NonBG) were examined by panoramic radiography and posteroanterior cephalography taken before and after canine eruption. Subjects were categorized into BG, NonBG, and control groups. Canines at the pre-eruption stage were categorized as close to (group 1) or distant from (group 2) the cleft area. The canine angle and its change between the two stages were evaluated. Results No significant differences were noted between the initial canine angle of the BG and NonBG groups. Although canines in the BG group erupted without a significant change in angle, the canine angle increased significantly (p < .0001) in the NonBG and control groups. In group 1, a greater change in canine angle was noted in the NonBG (p < .05) and control (p < .01) groups than in the BG group. In group 2, no significant difference was noted among the three groups. Conclusions In BG patients, a canine located near the cleft appears to erupt at the same angle as it had before grafting. However, in NonBG patients, it erupts more vertically, guided by cortical bone. For canines distant from the cleft area, there is no significant difference in the change in angulation between NonBG and BG patients.

scholarly journals Damage detection by recurrence and entropy methods on the basis of time series measured during composite milling

2020 ◽  
Vol 111 (1-2) ◽  
pp. 549-563
Author(s):  
Krzysztof Kecik ◽  
Krzysztof Ciecielag ◽  
Kazimierz Zaleski
Keyword(s):  
Time Series ◽  
Damage Detection ◽  
Approximate Entropy ◽  
Recurrence Plot ◽  
Milling Process ◽  
Fiber Reinforced Polymer ◽  
Reinforced Polymer ◽  
Glass Fiber Reinforced ◽  
Damage Indicators ◽  
Different Diameters

Abstract This paper presents methods for damage detection in machined material on the basis of time series measured during milling of glass-fiber–reinforced polymer (GFRP). Recurrence methods and different types of entropy have emerged as useful tools for detecting subtle non-stationarities and/or changes in nonlinear signals. In this research, a recurrence plot, recurrence quantifications, an approximate entropy, and sample entropy are used. By identifying changes in the cutting force measured during the composite milling process, the damage occurrence has been detected. Firstly, the damage has been modelled as the intentionally introduced hole with different diameters and depths in order to estimate the size detectable damages and to select proper recurrence measures as damage indicators. Next, the experiments with the real damage have been performed and the damage indicators have used.

scholarly journals New possibilities of complex ttreatment of cervical ectropion

2021 ◽  
pp. 12-22
Author(s):  
N. F. Khvorostukhina ◽  
D. A. Novichkov ◽  
N. N. Stepanova
Keyword(s):  
Central Zone ◽  
Statistical Processing ◽  
Cervical Canal ◽  
Viral Pathogen ◽  
Diagnostic Measures ◽  
Ultrasound Diagnostics ◽  
Cytological Picture ◽  
Group 2 ◽  
Two Stages ◽  
Group 1

Introduction. Ectropion of the cervix (EC) is a condition when there is a cicatricial deformity of the uterine cervix (as a result of traumatic injuries) with visualization of the ectopic columnar epithelium on the vaginal part of it. The ectopia is currently classified as a variant of the normal histophysiological state of the cervix. This article discusses the features of the course and methods of treatment of complicated EC.Objective of the study is: to develop and evaluate the effectiveness of a new method of complex treatment of CE.Material and methods. In an open prospective study, 133 patients with CE (groups 1 and 2) and 56 healthy women (group 3) has taken part. In group 1 (n = 83), we have used a method for treating CE developed by us, which included two stages: stage I – elimination of microbial and viral pathogen in combination with immunomodulatory therapy, II – electrosurgical treatment (Leep biopsy) and treatment of the cervix with Galavit (100 mg of dry matter) dissolved in 5 ml of Miramistin (Patent for invention RU 2568768 C1). In group 2 (n = 50), surgical treatment of CE has been preceded by vaginal sanitation, empirical antibacterial and antiviral therapy. Diagnostic measures, in addition to standards, have included: determination of interleukins IL-1β, IL-6, IL-8, IL-10 in the discharge of the cervical canal, ultrasound diagnostics with Doppler measurements in the vessels of the central zone of the cervix. Statistica 7.0, SPSS 17 packages have been used for statistical processing.Results and discussion. Before the start of treatment, patients in groups 1 and 2 have been found to have a combination of CE with cervicitis (100%), ASCUS cytological picture (more than 60%), abnormal colposcopic signs (100%), imbalance of the local immune system with a predominance of Th1 cytokines (the content of IL-8 increased 2.6 times; IL-1b – 13 times; IL-6 – 20 times, and IL-10 – in 1.7 times) against the background of increased vascularization and cervical perfusion. The reparative process after Leep biopsy in group 1 has ended by the end of 3 weeks in 65.6% of patients, in group 2 – in 25.5%, after 5 weeks – in 100% and 57.4%, respectively, after 8 – in group 2, 91.5%. The average period of epithelialization of a wound on the cervix in group 1 was 27.4 ± 4.3 days, in group 2 – 39.5 ± 5.6 days (p = 0.01). After 2 years, the recurrence of cervical pathology has been recorded only in group 2 (34.0%).Conclusion. The use of the developed method of two-stage complex therapy for CE increases the effectiveness of treatment, prevents complications after Leep biopsy, accelerates epithelialization by 30.6% and avoids recurrence of the disease.

scholarly journals Rotating Scheimpflug Imaging Indices in Different Grades of Keratoconus

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Sherine S. Wahba ◽  
Maged M. Roshdy ◽  
Rania S. Elkitkat ◽  
Karim M. Naguib
Keyword(s):  
Receiver Operating Characteristic Curve ◽  
Central Corneal Thickness ◽  
Operating Characteristic ◽  
Characteristic Curve ◽  
Corneal Thickness ◽  
Scheimpflug Imaging ◽  
Operating Characteristic Curve ◽  
Group 2 ◽  
Different Diameters ◽  
Group 1

Purpose. To evaluate accuracy of various Keratoconus (KC) screening indices, in relation to Topographic Keratoconus (TKC) grading.Setting. Al Watany Eye Hospital, Cairo, Egypt.Methods.Data of 103 normal (group 1) and 73 KC eyes (group 2), imaged by Pentacam (branded as Allegro Oculyzer), were analysed.Group 2was divided into2a: 14 eyes (TKC = 1, early KC),2b: 25 eyes (TKC = 1 to 2 or 2, moderate KC), and2c: 34 eyes (TKC = 2 to 3 up to 4, severe KC). Participants were followed up for six years to confirm diagnosis. Area under the receiver operating characteristic curve (AUROC) was calculated for evaluated curvature, elevation, and pachymetry indices with various reference shapes at different diameters.Results. When comparing normal to KC eyes, ten indices had significantly higher AUROC. Only five of them had significantly higher AUROC in early KC compared to normal corneas: Pachymetry Progression Index- (PPI-) Maximum (Max), Ambrósio’s Relational Thickness- (ART-) Max, PPI-Max minus PPI-Minimum (Min), central corneal thickness (CCT), and diagonal decentration of thinnest point from the apex (AUROC = 0.690, 0.690, 0.687, 0.683, and 0.674, resp.).Conclusion. Generally, ten pachymetry and elevation-based indices had significantly higher AUROC. Five indices had statistically significant high AUROC when comparing early KC to normal corneas.

Thermography signs of lung inflammation

2021 ◽  
pp. 39-44
Author(s):  
I. M. Dolgov ◽  
M. G. Volovik
Keyword(s):  
Infrared Thermography ◽  
Lung Inflammation ◽  
Cloud Storage ◽  
Lower Lobe ◽  
Front Surface ◽  
Mean Temperature ◽  
Group 2 ◽  
Confidence Value ◽  
Inflammation Group ◽  
Group 1

The purpose of the study was to find out if infrared thermography of the thorax is the method to select the patients with lung inflammationMaterial, methods: Thermograms were accumulated and processed in the «TVision» cloud storage («Dignosis», Russia). Special regions of interest (ROI) were automatically created: 1. on the front and back of the thorax roughly in the projection of the upper lobe (ULP) and the lower lobe (LLP) of the lung; 2.e lines on the front surface of the thorax. Two types of temperature gradients were calculated: between ULP and LLP (by subtraction mean temperature in LLP from mean temperature in ULP) (ΔT1); between both ULP and both LLP on the back of the thorax (ΔT2). Approximation confidence value for the polynomial trend line (R²) along the marked lines on the front surface of the thorax also calculated. Totally 489 thermograms, were analyzed, included 337 from healthy patients (group 1) and 152 from patients with confirmed diagnosis of lung inflammation (group 2)Results: R² value was higher in the group 1 compare to group 2 (0.58 ± 0.16 vs 0.3 ± 0.2, p < 0.05). ΔT1 value was negative only in patients from group 2, as well as ΔT1 value greater than 0.4 °C.Conclusion: three independent thermographic criteria suitable for detecting lung inflammation were found, so infrared thermography is the valuable method for screening this pathology.

scholarly journals COMPLICATIONS RELATED TO GASTRIC BYPASS PERFORMED WITH DIFFERENT GASTROJEJUNAL DIAMETERS

2016 ◽  
Vol 29 (suppl 1) ◽  
pp. 12-14 ◽  
Author(s):  
José SAMPAIO-NETO ◽  
Alcides José BRANCO-FILHO ◽  
Luis Sérgio NASSIF ◽  
Anne Caroline BROSKA ◽  
Douglas Jun KAMEI ◽  
...  
Keyword(s):  
Gastric Bypass ◽  
Statistical Significance ◽  
Gastrojejunal Anastomosis ◽  
Site Infection ◽  
Early Complications ◽  
Group 2 ◽  
Treatment Of Obesity ◽  
Different Diameters ◽  
Surgical Treatment Of Obesity ◽  
Group 1

ABSTRACT Background: Among the options for surgical treatment of obesity, the most widely used has been the Roux-en-Y gastric bypass. The gastrojejunal anastomosis can be accomplished in two ways: handsewn or using circular and linear stapled. The complications can be divided in early and late. Aim: To compare the incidence of early complications related with the handsewn gastrojejunal anastomosis in gastric bypass using Fouchet catheter with different diameters. Method: The records of 732 consecutive patients who had undergone the bypass were retrospectively analyzed and divided in two groups, group 1 with 12 mm anastomosis (n=374), and group 2 with 15 mm (n=358). Results: The groups showed anastomotic stenosis with rates of 11% and 3.1% respectively, with p=0.05. Other variables related to the anastomosis were also analyzed, but without statistical significance (p>0.05). Conclusion: The diameter of the anastomosis of 15 mm was related with lower incidence of stenosis. It was found that these patients had major bleeding postoperatively and lower surgical site infection, and in none was observed presence of anastomotic leak.

Performance of externally bonded fiber-reinforced polymer retrofits in the 2018 Cook Inlet Earthquake in Anchorage, Alaska

2021 ◽  
pp. 875529302110286
Author(s):  
Jovan Tatar ◽  
Siamak Sattar ◽  
David Goodwin ◽  
Sandra Milev ◽  
Shafique Ahmed ◽  
...  
Keyword(s):  
Outdoor Exposure ◽  
Field Investigation ◽  
Fiber Reinforced Polymer ◽  
Fiber Reinforced ◽  
Bond Quality ◽  
Cook Inlet ◽  
Reinforced Polymer ◽  
Glass Fiber Reinforced ◽  
Externally Bonded ◽  
Earthquake Effects

As part of the effort to improve the seismic performance of buildings in Alaska (AK), many of the deficient structures in Anchorage, AK, were retrofitted—some with externally bonded fiber-reinforced polymer (EBFRP) composite systems. The 2018 magnitude 7.1 Cook Inlet earthquake that impacted the same region offered an opportunity to evaluate the performance of EBFRP retrofits in a relatively high-intensity earthquake. This study summarizes the following findings of this field investigation: (1) the performance of EBFRP-retrofitted structures in the Cook Inlet earthquake and (2) the observations concerning the condition of FRP retrofits from over a decade of exposure in a subarctic environment. A deployment team from the National Institute of Standards and Technology (NIST) in collaboration with the University of Delaware (UD) Center for Composite Materials conducted post-earthquake inspections of EBFRP retrofits in multiple buildings to assess their performance during the earthquake and condition with respect to weathering. EBFRP debonding was documented with infrared thermography and acoustic sounding and the bond quality between EBFRP and concrete was assessed using pull-off tests. Visual inspections showed no major signs of earthquake damage in the EBFRP-retrofitted components. However, evaluation of debonding and pull-off test results suggested that outdoor conditions may have led to bond deterioration between EBFRP and concrete from installation defects that grew over time, freeze–thaw expansion from moisture present at the FRP/concrete interface, differences in thermal expansion of the materials, or a combination thereof. The carbon fiber–reinforced polymer (CFRP) bond to concrete was found to be more vulnerable to outdoor exposure than the glass fiber–reinforced polymer (GFRP) bond. Earthquake effects on FRP/concrete bond could not be assessed due to the lack of baseline data.

scholarly journals Does Deeper Involvement in Lexical Input Processing during Reading Tasks Lead to Enhanced Incidental Vocabulary Gain?

2017 ◽  
Vol 5 (3) ◽  
pp. 406
Author(s):  
Patricia Kolaiti ◽  
Panagiota Raikou
Keyword(s):  
Vocabulary Retention ◽  
Search Tasks ◽  
Input Processing ◽  
Study Support ◽  
Involvement Load ◽  
Group 2 ◽  
Two Stages ◽  
Reading Activity ◽  
Reading Activities ◽  
Group 1

<p><em>This paper investigates whether increased learner involvement in search tasks during reading activities results in differential vocabulary acquisition in an incidental setting in line with Hulstijn and Laufer’s (2001) Involvement Load Hypothesis. We designed and conducted an experiment with two groups of advanced</em> <em>Greek learners of English, an online dictionary-search group (Group 1) and a non-search group (Group 2) with the aim to test whether increased learner involvement in search tasks results in differential vocabulary retention. During a reading activity, participants of Group 1 were asked to find the meanings of 10 target words involved in the reading activity by using the online Google-dictionary and also find and write down a sentence relevant to the meaning of each target word. These two tasks were designed with the aim to activate the involvement factor “search” in line with Hulstijn and Laufer’s (2001) three-factor Involvement Load construct. During the same reading activity, participants in Group 2 were simply given the meanings of the 10 target items on a separate sheet of paper (glossary). The experiment was conducted in two stages with one week’s distance between them involving an immediate and a delayed vocabulary test aimed to assess short-term and long-term vocabulary retention respectively. The results of our study support the increased learner involvement hypothesis, as the dictionary-search group outperformed the non-search group in both tests.</em></p>

Nanomechanical properties, surface topography, and color stability of fiber-reinforced composite orthodontic retainers

2019 ◽  
Vol 27 (2) ◽  
pp. 92-100 ◽  
Author(s):  
Ibrahim Alshahrani ◽  
Moshabab A Asiry ◽  
Mohamad K Altwijry ◽  
Sangeetha N Premanath ◽  
Ravikumar Ramakrishnaiah ◽  
...  
Keyword(s):  
Elastic Modulus ◽  
Color Change ◽  
Color Stability ◽  
Fiber Reinforced ◽  
Nanomechanical Properties ◽  
Glass Fiber Reinforced ◽  
Polyethylene Fiber ◽  
Significant Difference ◽  
Group 2 ◽  
Group 1

The present study investigated the nanomechanical properties, surface topography, and color alterations of fiber-reinforced composite (FRC) orthodontic retainers. Two FRC orthodontic retainer materials (glass fiber reinforced (group 1) and polyethylene fiber reinforced (group 2)) were evaluated. Nanomechanical properties (nano-hardness and elastic modulus), surface roughness (Ra), and color stability of FRC retainers at baseline and after 2 years of simulated aging were evaluated. The data collected were analyzed using analyses of variance, followed by Tukey’s honestly significant difference test for post hoc comparisons at the significance level of p < 0.05. Group 1 specimens exhibited highest hardness (0.16 ± 0.06) and elastic modulus (2.68 ± 0.17) at baseline, and group 2 specimens showed lowest hardness (0.09 ± 0.16) and elastic modulus (2.19 ± 0.36) after aging. Significant difference in hardness and elastic modulus was observed between the groups at baseline and after aging ( p < 0.05).The aged specimens demonstrated decreased hardness and elastic modulus values compared to baseline specimens, but the differences were not significant ( p > 0.05). Group 2 specimens exhibited increased Ra at baseline (0.46 ± 0.79) and aging (0.84 ± 0.94), and the least Ra values were observed with group 1 specimens at baseline (0.31 ± 0.87) and aging (0.59 ± 0.65). There was a significant color alteration of the specimens from baseline to aging in both the groups ( p < 0.05). However, group 1 specimens showed noticeable color change, and group 2 showed appreciable color change. Glass fiber-reinforced FRC orthodontic retainer exhibited superior properties compared to polyethylene fiber-reinforced FRC. Accelerated aging decreases surface hardness of the polymer matrix and increases Ra and discoloration of the FRC retainer materials.

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