The Experts below are selected from a list of 111 Experts worldwide ranked by ideXlab platform
Satoshi Kobayashi - One of the best experts on this subject based on the ideXlab platform.
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Acoustic emission detection and position identification of transverse cracks in carbon fiber–reinforced Plastic Laminates by using a novel optical fiber ultrasonic sensing system
Structural Health Monitoring, 2015Co-Authors: Qi Wu, Fengming Yu, Yoji Okabe, Kazuya Saito, Satoshi KobayashiAbstract:Utilizing optical fiber technique to structural health monitoring of composite materials is attracting attention recently due to the inherent advantages in optical fiber sensor. However, acoustic emission signals with low energy and high frequency from transverse cracks in carbon fiber-reinforced Plastic Laminates are difficult to be detected by normal optical techniques. In this work, we present a phase-shifted fiber Bragg grating balanced sensing system to detect acoustic emission signals generated in a carbon fiber-reinforced Plastic Laminate in a three-point bending test. We demonstrated that the phase-shifted fiber Bragg grating balanced sensing system with a broad bandwidth and high sensitivity can detect high-frequency, low-energy acoustic emission signals caused by transverse cracks. In our experiments, the transverse cracks were identified very well through the detected acoustic emission signals. The relationship between the strain and the acoustic emission signals, and the typical waveforms of the acoustic emission signals were investigated. Furthermore, accurate position identification using acoustic emission detection by the phase-shifted fiber Bragg grating sensor was demonstrated. All the results obtained from the phase-shifted fiber Bragg grating sensor were compared to the results obtained from commercial lead-zirconate-titanate acoustic emission sensors. We found that the phase-shifted fiber Bragg grating balanced sensing system performance was comparable to the commercial lead-zirconate-titanate acoustic emission sensors.
K. W. Thorpe - One of the best experts on this subject based on the ideXlab platform.
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Comparative efficacy of two controlled-release gypsy moth mating disruption formulations
Entomologia Experimentalis et Applicata, 1999Co-Authors: K. W. Thorpe, W. Mclane, B. A. Leonhardt, V. C. Mastro, D. S. Leonard, R. C. Reardon, S. E. TalleyAbstract:The effects of aerial applications of the gypsy moth sex pheromone, disparlure, on mating disruption and suppression of growth of populations of the gypsy moth, Lymantria dispar (L.), were investigated. Two formulations of disparlure, Plastic Laminate flakes applied in a single application and polymethacrylate beads applied in two applications, were compared in two separate tests conducted in 1993 and 1994. The beads were applied in two applications spaced 2 weeks apart because preliminary tests had indicated that they released pheromone too rapidly to maintain adequate emission rates throughout the period of male flight. In 1993, the flakes were applied at a rate of 50 g a.i./ha, and the beads were applied at a rate of 15 g a.i./ha for each application. In 1994, the flakes were applied at a rate of 75 g a.i./ha and the beads were applied at rates of 32.5 and 42.5 g a.i./ha for the two applications. Beads with larger average particle size were used in 1994 to prolong disparlure release. The treatments applied in 1993 resulted in >97% reduction in mating and >82% suppression of population growth in the following year. Because of a 1995 collapse of gypsy moth populations in the vicinity of the tests, reliable population growth data were not available for the treatments applied in 1994, but significant mating disruption did occur under both treatments. Based on measurements of residual disparlure after field aging, the flakes released 32 and 48% of their disparlure content during the 6 weeks of male moth flight in 1993 and 1994, respectively. The smaller beads used in 1993 released 75% of their disparlure content, and the larger beads used in 1994 released 52% of their disparlure content, during the 6 weeks of male flight. The biological efficacy data suggest that the bead and flake formulations, as applied in these tests, have similar effects on gypsy moth mating disruption and subsequent population growth. Based on the observed release rates from both 1993 and 1994, a single application of the beads would provide emission rates equal to or greater than those provided by the flakes when applied at an equal dose.
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Control of low-density gypsy moth (Lepidoptera: Lymantriidae) populations by mating disruption with pheromone
Journal of Chemical Ecology, 1996Co-Authors: B. A. Leonhardt, W. Mclane, V. C. Mastro, D. S. Leonard, R. C. Reardon, K. W. ThorpeAbstract:This four-year study demonstrated that low-density populations of the gypsy moth, Lymantria dispar (L.), were effectively suppressed by annual aerial application of 75 g of racemic disparlure per hectare formulated in Plastic Laminate flakes. These tests also showed that, when plots were treated with 150 g of pheromone per hectare in 1990 only and left untreated for the following three years, populations continued to be suppressed in 1991–1993 as compared with the controls. Although none of the plots were treated in 1994, population assessment continued and showed that the gypsy moth population density remained low in the plots that had been treated annually for the preceding four years. The Laminate flakes released an average of 0.48 g disparlure per day per hectare from each of the two applications in 1990, and 0.72 g per day per hectare from the single application in each of the following three years (1991–1993). Only 27–40% of the applied pheromone dose was emitted during male moth flight.
Dayang Laila Abang Abdul Majid - One of the best experts on this subject based on the ideXlab platform.
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condition structural index using principal component analysis for undamaged damage and repair conditions of carbon fiber reinforced Plastic Laminate
Journal of Intelligent Material Systems and Structures, 2014Co-Authors: Khairul Dahri Mohd Aris, Faizal Mustapha, Mohd Sapuan Salit, Dayang Laila Abang Abdul MajidAbstract:This article deals with the data reduction technique using the principal component analysis applied to the carbon fiber–reinforced Plastic panels for structural health monitoring approaches. Two carbon fiber–reinforced Plastic panels subjected to damage and repair coincide with typical aircraft repair procedures found in the aircraft structural repair manual. The panels were simulated with 30 mm diameter of partial and full penetration damages using a diamond-coated router. The data (50 observations) were captured for the undamaged, damaged, and repaired conditions by placing lead zirconate titanate smart sensors at 100 mm across the damaged and repaired structures. A time-based data response was captured for post analysis during the interrogation on the structure at each condition. The raw data were captured in a Lamb waveform, and the interested features were extracted using Morlet wavelet analysis to evaluate the Condition Structural Index and Amplitude-Based Assessment for each condition retrieved from the Gaussian-like distribution. The results were evaluated using the principal component analysis technique in order to distinguish the characteristic of the undamaged, damaged, and repaired conditions. The results showed that in all cases considered, it was possible to distinguish the conditions of undamaged, damaged, and repaired states with promising accuracy and repeatability of the data.
W. Mclane - One of the best experts on this subject based on the ideXlab platform.
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Effectiveness of gypsy moth mating disruption from aerial applications of Plastic Laminate flakes with and without a sticking agent
Agricultural and Forest Entomology, 2000Co-Authors: Kevin W. Thorpe, Donna S. Leonard, Victor C. Mastro, W. Mclane, Richard C. Reardon, P. Sellers, Ralph E. Webb, S. E. TalleyAbstract:Summary 1 The Plastic Laminate flake formulation, Disparlure II, is currently the only gypsy moth mating disruption product available for aerial application. The elimination of a sticking agent from the formulation would reduce costs, simplify application, and make it possible to apply the product without specialized equipment. 2 A test was conducted in wooded plots in Virginia during 1997 and 1998 to determine whether a sticking agent is necessary. Treatment effectiveness was assessed from the rates of male moth capture in pheromone-baited traps and mating success of both laboratory-reared and wild females. 3 Male moth capture was reduced 75.6 and 92.9% in plots treated with flakes without and with a sticking agent, respectively. The percentage of mated females that produced egg masses with more than 5% fertile eggs was reduced by 86.3 and 99.5% in plots treated with flakes without and with a sticking agent, respectively. 4 Moth capture and mating success of laboratory-reared females did not differ significantly between plots treated with flakes with and without a sticking agent. However, the consistently greater reduction in mating success in both years provides strong evidence that mating disruption is less effective when flakes are applied without a sticking agent. The proportion of wild egg masses collected in 1998 with more than 5% fertile eggs was significantly higher under the no-sticking agent treatment. 5 In special situations where the use of a sticking agent may be problematic, such as in residential areas, the data indicate that a high level of mating disruption is likely to occur even without the use of a sticking agent.
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Comparative efficacy of two controlled-release gypsy moth mating disruption formulations
Entomologia Experimentalis et Applicata, 1999Co-Authors: K. W. Thorpe, W. Mclane, B. A. Leonhardt, V. C. Mastro, D. S. Leonard, R. C. Reardon, S. E. TalleyAbstract:The effects of aerial applications of the gypsy moth sex pheromone, disparlure, on mating disruption and suppression of growth of populations of the gypsy moth, Lymantria dispar (L.), were investigated. Two formulations of disparlure, Plastic Laminate flakes applied in a single application and polymethacrylate beads applied in two applications, were compared in two separate tests conducted in 1993 and 1994. The beads were applied in two applications spaced 2 weeks apart because preliminary tests had indicated that they released pheromone too rapidly to maintain adequate emission rates throughout the period of male flight. In 1993, the flakes were applied at a rate of 50 g a.i./ha, and the beads were applied at a rate of 15 g a.i./ha for each application. In 1994, the flakes were applied at a rate of 75 g a.i./ha and the beads were applied at rates of 32.5 and 42.5 g a.i./ha for the two applications. Beads with larger average particle size were used in 1994 to prolong disparlure release. The treatments applied in 1993 resulted in >97% reduction in mating and >82% suppression of population growth in the following year. Because of a 1995 collapse of gypsy moth populations in the vicinity of the tests, reliable population growth data were not available for the treatments applied in 1994, but significant mating disruption did occur under both treatments. Based on measurements of residual disparlure after field aging, the flakes released 32 and 48% of their disparlure content during the 6 weeks of male moth flight in 1993 and 1994, respectively. The smaller beads used in 1993 released 75% of their disparlure content, and the larger beads used in 1994 released 52% of their disparlure content, during the 6 weeks of male flight. The biological efficacy data suggest that the bead and flake formulations, as applied in these tests, have similar effects on gypsy moth mating disruption and subsequent population growth. Based on the observed release rates from both 1993 and 1994, a single application of the beads would provide emission rates equal to or greater than those provided by the flakes when applied at an equal dose.
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Control of low-density gypsy moth (Lepidoptera: Lymantriidae) populations by mating disruption with pheromone
Journal of Chemical Ecology, 1996Co-Authors: B. A. Leonhardt, W. Mclane, V. C. Mastro, D. S. Leonard, R. C. Reardon, K. W. ThorpeAbstract:This four-year study demonstrated that low-density populations of the gypsy moth, Lymantria dispar (L.), were effectively suppressed by annual aerial application of 75 g of racemic disparlure per hectare formulated in Plastic Laminate flakes. These tests also showed that, when plots were treated with 150 g of pheromone per hectare in 1990 only and left untreated for the following three years, populations continued to be suppressed in 1991–1993 as compared with the controls. Although none of the plots were treated in 1994, population assessment continued and showed that the gypsy moth population density remained low in the plots that had been treated annually for the preceding four years. The Laminate flakes released an average of 0.48 g disparlure per day per hectare from each of the two applications in 1990, and 0.72 g per day per hectare from the single application in each of the following three years (1991–1993). Only 27–40% of the applied pheromone dose was emitted during male moth flight.
Qi Wu - One of the best experts on this subject based on the ideXlab platform.
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Acoustic emission detection and position identification of transverse cracks in carbon fiber–reinforced Plastic Laminates by using a novel optical fiber ultrasonic sensing system
Structural Health Monitoring, 2015Co-Authors: Qi Wu, Fengming Yu, Yoji Okabe, Kazuya Saito, Satoshi KobayashiAbstract:Utilizing optical fiber technique to structural health monitoring of composite materials is attracting attention recently due to the inherent advantages in optical fiber sensor. However, acoustic emission signals with low energy and high frequency from transverse cracks in carbon fiber-reinforced Plastic Laminates are difficult to be detected by normal optical techniques. In this work, we present a phase-shifted fiber Bragg grating balanced sensing system to detect acoustic emission signals generated in a carbon fiber-reinforced Plastic Laminate in a three-point bending test. We demonstrated that the phase-shifted fiber Bragg grating balanced sensing system with a broad bandwidth and high sensitivity can detect high-frequency, low-energy acoustic emission signals caused by transverse cracks. In our experiments, the transverse cracks were identified very well through the detected acoustic emission signals. The relationship between the strain and the acoustic emission signals, and the typical waveforms of the acoustic emission signals were investigated. Furthermore, accurate position identification using acoustic emission detection by the phase-shifted fiber Bragg grating sensor was demonstrated. All the results obtained from the phase-shifted fiber Bragg grating sensor were compared to the results obtained from commercial lead-zirconate-titanate acoustic emission sensors. We found that the phase-shifted fiber Bragg grating balanced sensing system performance was comparable to the commercial lead-zirconate-titanate acoustic emission sensors.