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Acoustic communication between Microcerotermes crassus Snyder
1982 - IRG/WP 1158
An unusual acoustic communication within a nest of Microcerotermes crassus SNYDER is reported. The signals produced by the termites are described and possible reasons for this behavior are considered.
U Kny


Detection of feeding behaviour of termites using AE monitoring
1991 - IRG/WP 1514
Using acoustic emission (AE) monitoring, the feeding activity of the termite inhabiting a wood specimen was investigated. The amplitude and the rate of AE from the specimen of Coptotermes formosanus Shiraki was larger than that of Reticulitermes speratus Kolbe. The AE event rate was higher in the specimen with soldiers than without soldiers. The AE event rate decreased according to the resistance of wood specimens against termite attack.
Y Imamura, M Tokoro, M Owada, Y Fujii, M Noguchi


The role of communication in the field of environment protection: A case study "Wood Protection"
1990 - IRG/WP 3574
L Wöss


Feasibility of termite control using crushed cement-stabilized sludge (Polynite) as a physical barrier and acoustic emission (AE) monitoring
2000 - IRG/WP 00-10381
In Japan, the damages by the subterranean termites (Coptotermes formosanus Shiraki and Reticulitermes speratus Kolbe) are more common. Recently, the more attention is paid to the methods of the termite controls of less- or non-chemical. As one of the non- chemical treatment, physical barrier using particles as basalts 1) , granites, and gravels 2) were investigated in terms of its safety, cost effectiveness and duration of performance, and there were also examples that the physical barriers using some particles have been put to practical use in a few countries except in Japan. Ebeling and Pence showed that the relationship between particle size and termite body size is an important factor in controlling tunneling activity of subterranean termites, and the crushed volcanic cinders of 0.85-2.36 mm in diameter prevented R. hesperus from penetrating 3) . Tamashiro and co- workers indicated that the particles of particular sizes (1.70-2.40 mm in diameter) prevented C. formosanus from penetrating 4) . Su and co- workers investigated the penetration of the sand barrier consisting of crushed quartz rocks and fossilized coral by C. formosanus in laboratory- and field-testing 5, 6) . These results show that it is important to investigate the relationships between the size of termites and particles to evaluate the effects of the physical barrier using particles. On the other hand, in Japan surplus soils and sludge of sixty million tons per annum are discharged from construction sites. The recycle techniques using the surplus soils and sludge and the development of the market for these recycled products are the theme of importance. The crushed cement- stabilized sludge (Polynite) as one of the recycled products of surplus soils and sludge is one of the newly developed and recycled material. It is technically suitable for mass production, has grate cost effectiveness, and is easy to uniform the particle size. In this study, the feasibility of a physical barrier using Polynite uniformed the particle size for termite was examined in a laboratory testing. AE monitoring 7-13) as a method forthe detection of the penetration of termites into the Polynite barrier at an early stage was also investigated, for the application of Polynite barrier in the house.
Y Yanase, M Shibata, Y Fujii, S Okumura, K Iwamoto, T Nogiwa, T Yoshimura, Y Imamura


Feasibility of AE (Acoustic Emission) monitoring for the detection of the activities of wood-destroying insects
1992 - IRG/WP 92-2416
The feasibility of acoustic emission (AE) as a nondestructive testing method for the detection of the wood destroying insects was investigated. AEs were detected from the wood specimens under feeding attack of sugi bark borers or powder-post beetles. However, the feasible monitoring area of an AE sensor is influenced by the attenuation of AE amplitude, so that this could be a problem in the practical AE measurements, especially with wood specimens of higher moisture content.
Y Fujii, Y Imamura, E Shibata, M Noguchi


Detection of Acoustic Emission (AE) generated by termite attack in a wooden house
1999 - IRG/WP 99-20166
Recently, considerable attention has been paid to methods for termite control, which involves few or no chemicals. To reduce the amount of termiticide needed, it is necessary to detect termite attack in wood as early as possible. The feasibility of acoustic emission (AE) monitoring for the nondestructive detection of termite attack has been discussed previously. In this study, we propose some technical solution for the application of AE monitoring to practical control operations. Using a needle-type waveguide combined with an AE sensor (PZT sensor), AEs generated and propagated within floors and walls could be detected effectively. A 0.04 mm-thick sample of the piezoelectric polymer PVDF, which was inserted between the construction members of wooden houses, could detect Aes propagated both in such members and at joint surfaces, although PVDF film is less sensitive than a PZT sensor. The feasibility of using a portable AE detector as the input device for a total security system against termite attack in a house is also discussed.
Y Fujii, Y Yanase, T Yoshimura, Y Imamura, S Okumura, M Kozaki


Detection of termite attack in wood using AE monitoring
1990 - IRG/WP 2355
An acoustic emission (AE) monitoring method for detecting termite activity in wood was applied to lumber of 3 by 3 cm to 10 by 10 cm square, 1 m long. Furthermore, the propagation of AEs due to the feeding activities of termites in the specimens and the locations of AE sources were analyzed. Also discussed was the feasibility of the method applied to posts out in the field of subterranean termites. The results obtained from laboratory and field tests suggest that AE monitoring could be an effective non-destructive method to detect feeding activity of termites even in the incipient stages of the termite attack in wood.
Y Fujii, M Owada, M Noguchi, Y Imamura, M Tokoro


A Long-term Observation of Termite Activity in The Nest by Continuous Acoustic Emission (AE) Monitoring
2003 - IRG/WP 03-20280
In order to evaluate the influence of temperature on the termite activity, acoustic emission (AE) monitoring was applied to two nests of Coptotermes formosanus SHIRAKI; a nest in the stem of a standing tree and a nest in the underground of a wooden house, respectively. Temperature change in and around the nests were continuously measured for about one year using thermocouples at four points; the centre of the nest, the periphery of the nest, the environment around the nest, and the underground, respectively. AEs were detected at the centre of nest and underneath the nest sphere by using wave-guides inserted into the nest of the standing tree and at the centre of nest. AEs were also detected at the wooden construction member near the nest in the wooden house. The termites in the nests were periodically stimulated by rotating, drawing and sticking the wave-guides. The temperatures in the both nests varied from 5 to 35 °C during the experiment. The highest and the lowest temperatures were recorded in August and February, respectively. The highest AEs event rate was recorded when the temperature of the nest in the tree was between 30 and 35 °C and when the temperature of the nest under the house was above 25 °C. In winter, when the nest temperature was below 10 °C, no significant numbers of AE were detected. These findings clearly show that AE generation has a close relation to the termite activities, which are influenced by the temperature in the nest.
Y Yanase, Y Fujii, S Okumura, T Yoshimura, Y Imamura


Using AE monitoring for detecting economically important species of termites in California
1991 - IRG/WP 2375
Acoustic emission (AE) monitoring was conducted on wooden samples containing three economically important species of termites in California (dampwood termite, Zootermopsis nevadensis, Western drywood termite, Incisitermes minor, and Western subterranean termite, Reticulitermes hesperus). Laboratory AE studies included varying termite species, as well as 7 day studies exploring the periodicity of termite behavior. The results from the laboratory tests revealed significant differences in AE events between species, days, and sensors used. In a second study, the distance that AE signals could be detected in 2.6 m (8 ft.) long, 52 x 102 mm² (2 by 4 in.) wooden studs was also explored for the dampwood termite. Acoustic emission signals were detectable for up to 2.2 m in wood for dampwood termites. This study is compared with other investigations exploring the feasibility of using AE to detect termites.
V R Lewis, R L Lemaster, F C Beall, D L Wood


Detection of Termite Attack to Wood Stakes in a Monitoring Station Using Ceramic Gas Sensors and Acoustic Emission (AE) Sensor
2003 - IRG/WP 03-20271
To evaluate the termite activity in monitoring stations non-destructively, metabolic gas from termites and acoustic emission generated by feeding of termites were measured. Ten cylindrical stations with small wood stakes of Japanese red pine (Pinus densiflora) were buried around a house attacked by Coptotermes formosanus SHIRAKI. A sample air in the station was collected by sucking through a drilled hole of the station lid and analyzed using two types of ceramic gas sensors (odour- and hydrogen-selective sensors). Acoustic emissions (AEs) were detected by a PZT sensor attached to the cross section of one of the small stakes in the station. The concentrations of two components of the collected gas, odour and hydrogen, and AE event rate per 2 minutes were measured periodically from December 2001 to February 2003. The infestation activity in the station was also evaluated by visual inspection. In the early stage of the experiment, from the first to the third measurements, neither AEs nor significant level of the gas concentration was detected, and no termite was found in any stations. A higher gas concentration of odour and hydrogen and a larger number of AE events were detected since termites have invaded in the stations. These findings suggest that termite attack in the monitoring station can be evaluated by using two types of the gas sensors and AE sensor.
Y Yanase, Y Fujii, S Okumura, T Yoshimura, Y Imamura, T Maekawa, K Suzuki


Ability of an acoustic inspection device to detect internal voids in untreated pole sections
2002 - IRG/WP 02-20246
Detecting deterioration before substantial losses in material properties occur poses a major challenge to most wood users. While physical inspection techniques such as drilling or coring are useful, these methods can miss small pockets of damage and they lack the ability to detect early or incipient decay. The development of sonic test methodologies has created the potential for detecting changes in material properties at relatively early stages of attack, but these technologies have suffered from an inability to separate normal wood characteristics from changes associated with degradation. One aspect of these methods that might prove useful, however, is their ability to detect small voids such as those caused by termites or beetles. This ability would be especially useful for assessing termite infestations in large structures. There is little data on the ability of many commercial devices to quantify termite damage. We assessed the ability of one device, the PURL-1, to detect increasing levels of simulated insect voids in Douglas-fir pole sections. The device was capable of detecting damage when as little as 1% of the cross section was removed. While the device was less successful at precisely quantifying the cross sectional area loss, the results suggest that this device has promise for early detection of small voids.
J J Morrell, R G Rhatigan


Control of termite attack using a trapping method and acoustic emission (AE) monitoring a case study at an electric power plant
1997 - IRG/WP 97-10224
To prevent subterranean termites (Coptotermes formosanus Shiraki and Reticulitermes speratus Kolbe) from invading the buildings of an electric power plant and to control their attack, artificial traps were buried around the buildings. The attack of the termites in and around the traps was monitored by detecting acoustic emissions (AE) generated by the feeding behavior of the workers. The cylindrical artificial traps were 600 mm long and 300 mm in diameter, and consisted of pieces of Japanese red pine surrounded by slender polystyrene foam sticks. Termite inhabitation was observed in eight of the ten traps set, and particularly high levels were found in three traps. The traps were renewed every one or two months. The amount of termites inhabiting the traps decreased drastically after the first renewal, but varied only slightly over the following two and a half years. The amount of termites in the traps increased when the traps were not renewed. Termite activity was significantly restricted by installing artificial traps and no additional serious attacks were found in or around the buildings during the study period. AEs generated by feeding activities were monitored by piezoelectric AE sensors attached to the wooden sticks in the traps or to wooden bait stakes near the trap. The rate of AE events varied according to feeding activity which was associated with the number of termites in the trap and the temperature.
Y Fujii, Y Imamura, E Iwatsubo, S Yamamoto


Make ready of a detection system for insect attack by acoustical method
1996 - IRG/WP 96-10183
A contract CRAFT of European research allowed to build a detector prototype able to diagnose on site the presence of Hylotrupes bajulus and termites, even during the first stages of infestation when no sign of activity is visible. Based on non destructive control technics, the device picks up the acoustical waves emitted by the insects in the wood fibers. The amplification and the filtering of the signal delivered by the piezo-electric sensors is made by an electronic module. The signal is numerized and transfered to a calculation processor. The diagnosis and automatic insect identification require a computer treatment by neuro-fuzzy processing. With the help of neural networks, it memorizes the sign of insects identified by an expert. This knowledge, translated in fuzzy logic is exploited to analyze in true time all sign coming in and automatically diagnose the level of infestation.
M Hyvernaud, F Wiest, M-M Serment, M Angulo, O Winkel


Acoustic technique for assessing decay in preservative treated wood
1998 - IRG/WP 98-20138
This study investigated the suitability of vibration techniques to assess the performance of wood preservatives in ground contact. Small stakes (10 x 5 x 100 mm3) of treated and untreated Scots pine sapwood were exposed to decay in lab-scale terrestrial ecosystems. Tests were conducted using three different soils including a garden compost soil, and soils obtained from a test field and a conifer forest in Sweden. Wood decay was monitored regularly for one year by determining wood mass losses. Also, strength losses were calculated from the dynamic modulus of elasticity (MOE) of sound and exposed wood specimens as determined by vibration measurements. The results of this study show that the MOE-dynamic losses for the different preservatives and environments have a very good correlation with mass losses. The limited efficiency of some preservatives in an aggressive environment (garden compost soil) was observed. The determination of dynamic modulus of elasticity seems to offer a good basis for assessing the performance of wood preservatives in laboratory soil tests.
L Machek, M-L Edlund, R Sierra-Alvarez, H Millitz


Detection of termite attack in wood using acoustic emission
1989 - IRG/WP 2331
Acoustic emission (AE) is the elastic wave produced by the strain energy released in the process of fracture of a material and propagates through it. The object of this report is to detect AEs produced by the termite activities and to evaluate the possibility of using an AE monitoring test to nondestructively detect the termite attack in wood. It was revealed that AEs were detected from the specimens under termite-attack and the rate of AE events increased according to the number of the inhabiting termites. As no AE was detected from the specimens with soldiers only, it was assumed that workers should generate AEs through feeding activities. It was also revealed that the distribution of AE sources corresponded to that of the region attacked by termites in the specimen.
Y Fujii, M Noguchi, Y Imamura, M Tokoro


Life Cycle Assessment of treated timber: methodological aspects and first results
2009 - IRG/WP 09-50264
Environmental information on products is more and more required as a key to the market, and the building sector in Europe is certainly advanced in that direction. In France, Environmental Product Declarations are becoming very common for construction products. Therefore, the CTB P+ and CTB B+ certification comity as commissioned FCBA to perform the Life Cycle Analysis of treated timber in order to publish EPDs of different types of treated timber products. The methodological choices and some selected first results about energy and climate change are presented.
E Vial, M Bertrand, C Cornillier, G Deroubaix


Use of Acoustic Emission (AE) to detect activity of common European dry-woodboring insects: some practical considerations
2013 - IRG/WP 13-10803
Old house borer (Hylotrupes bajulus), Furniture beetle (Anobium punctatum), and Deathwatch beetle (Xestobium rufovillosum) are common dry-woodboring insects occurring throughout Europe. With the aim to prevent unnecessary use of biocidal products, to protect valuable wooden elements and objects from unwanted influences, and to have a more objective method, SHR has started to study the use of acoustic emission (AE) to assess activity of attack by these insects. This manuscript deals with the results of some experiments done in order to collect knowledge about the influence of (low) temperature or possible daily rhythms on the activity of the insects. Such knowledge is crucial for a trustworthy application of AE detection for European dry-woodboring insects in practice. Based on an 8-day-test with Hylotrupes with normal daily variation in temperature it is concluded that under these circumstances, temperature is the main influencing factor regarding insect activity. For individual larvae, phases of inactivity exist with a duration of up to 30 minutes. In practice, where probably more than one larva is present at one specific time, in the absence of AE events, measuring periods may need to be extended to at least these 30 minutes. With regard to minimum temperatures for detection, the insect species studied show small differences in behaviour at low temperature. Because the number of registered hits for all species shows a marked decrease at temperatures becoming lower than 10 °C, it is recommended that decisive assessments using AE for detection of activity of these dry-woodboring insects should be done at (wood) temperatures of 10 °C or higher.
J G M Creemers


Nondestructive Detection of Biodeterioration in Indonesian Traditional Wooden Construction of “Joglo”
2014 - IRG/WP 14-10834
To decide the repairing and reinforcement method for wooden constructions, it is necessary to get the enough and precise information on the status of the construction beforehand, especially the distribution and the degree of the biodeterioration, such as decay or insect attack (e.g. termite attack). In this study, damage of biodeterioration to teak wood used in Indonesian traditional wooden construction of “Joglo” was investigated by evaluating ultrasonic velocity, moisture content, acoustic emission, and so on. Damages by dry-wood termite or fungi were found in joglo constructions in sultans’ palaces and in the area of Kotagete. The relationship of damages by dry-wood termite or fungi to ultrasonic velocity in the teak wood and to moisture content was discussed. The monitoring of acoustic emission generated by dry-wood termite attack was also carried out for the detection of termite attack in the wooden structure.
Y Yanase, T Mori, T Yoshimura, Y P Prihatmaji, J Sulistyo, S Doi


Remote sensing for detection of termite infestations—Proof of Concept
2015 - IRG/WP 15-10846
This paper reports the results of a search to discover the most cost effective and robust method of detecting Reticulitermes flavipes infestations in structural members of remote bridges, homes and other wooden structures and transmitting these results to internet cloud storage thus obviating routine travel to these structures for periodic visual inspections. Duplicate stainless steel tanks were constructed for housing R. flavipes colonies and commodity size dimension lumber members. Overall, results indicated that the simplest and cheapest independent variables to measure and send were: temperature (ºC), relative humidity (% RH); dew point (DPºC) and wood moisture content (WPE %) using off-the-shelf commercially available sensor systems. Above ground termite bait stations were determined to be the best method of housing the various sensors to permit ease of subsequent baiting if any termite activity was detected. We conclude that it is feasible and cost effective to monitor valuable wooden structures, like historic covered bridges, against termite infestation and potential structural damage.
F Green III, R A Arango, C R Boardman, K J Bourne, J C Hermanson, R A Munson


Nondestructive analysis of oviposition of the bamboo powderpost beetle Dinoderus minutus using acoustic emission and X-ray CT
2017 - IRG/WP 17-10889
The bamboo powderpost beetle Dinoderus minutus is a major pest of dry bamboo culms in Japan. In this study, acoustic emission (AE) and X-ray computed tomography (CT) was applied to the nondestructive analysis of the ovipositional behavior of adult D. minutus beetles inside bamboo pieces. Newly mated adult females were individually exposed to oviposition bamboo pieces prepared from culms of Phyllostachys bambusoides. AE measurement of the bamboo pieces were conducted continuously using AE sensors with a resonant frequency of 150 kHz. The bamboo pieces were scanned by the microfocus X-ray CT system with intervals of 2–5 d to observe the oviposition tunnels and eggs inside. Time courses of hourly AE hit rate showed that the female adults immediately started tunneling, and the tunneling activity continued almost ceaselessly. Oviposition tunnels bored across vascular bundles of bamboo and eggs deposited in the vessels were captured in X-ray CT images, and the length of oviposition tunnels and the number of eggs were measured.
H Watanabe, Y Yanase, Y Fujii


Effects of heat treatment on sound absorption coefficients in nanosilver-impregnated and normal solid woods
2017 - IRG/WP 17-40770
Effects of impregnation with silver nano-suspension as well as heat-treatment on sound absorption coefficients (AC) were studied in tangential direction of five different solid woods based on their importance. AC was measured at two frequencies of 250 and 500 Hz. A 400 ppm nanosuspension was used for the impregnation; silver nanoparticles had a size range of 30-80 nm. Based on the obtained results, the species reacted significantly different in absorbing sound at the two frequencies. Impregnation with nano-suspension substantially decreased AC at the lower frequency of 250 Hz; it did not show any particular trend when AC was measured at the frequency of 500 Hz. Heat treatment significantly increased AC at the frequency of 250 Hz. ACs of mulberry tended to be similar at the two frequencies; in the other four species though, ACs were significantly different. High significant correlations were found in the hardwoods between the ACs measured at the two frequencies.
A Esmailpour, J Norton, H R Taghiyari, H Zolfaghari, S Asadi


Word wrangling: the art of editing scientific publications
2019 - IRG/WP 19-50356
The main method by which scientists communicate their findings to the world is through journal papers, but many scientists struggle with the task of self-editing, and some find writing itself to be a chore. Understanding the different stages of editing, and what takes place in each of those stages, can help to reduce the complexity of the editing task, assist an author to self-edit, and reduce costs of engaging an editor at a later stage. Further, use of a variety of self-editing tools and resources can reduce the time it takes to edit a document and increase the accuracy of the edit. These include the use of a dictionary, creation of a word list, use of a style guide, and creation of a style list. There are also tools that are available in Microsoft Word as macros, add-ons and software. Some of these tools and resources can be used by the authors but others, because of cost or technical complexity, are used at the corporate-support level or by editors. Online resources may be used to assist in engaging an editor, and understanding the standards expected of a professional editor, codes of practice and expected codes of professional behaviour. Whether the intent is to self-edit, have a colleague review the document, or to engage an editor, the ultimate goal is to improve the communication of the author’s intended main points to the reader, and to ensure the paper itself is accurate, consistent and professional.
J Taylor


Comparison of AE-apparatus for detection of activity of Old house borer larvae, including reality check
2021 - IRG/WP 21-10981
As part of the German funded project ‘InsectDetect’ comparative measurements were done with three different Acoustic-Emission-(AE)-apparatus on 14 pine beams in order to assess presence of active attack by the Old house borer (Hylotrupes bajulus (L.)). In all beams active attack was measured, though in varying intensity. This was corroborated by completely dissecting 10 of the beams. All three AE-systems proved suitable to find active attack, although their results in terms of numbers of events are different even when used in the same situation. Therefore, it is important that the operator is familiar with the technical functioning of the system that is used in order to be able to interpret the results reliably. The dissection of the beams showed that there is also an element of chance in these measurements regarding proximity of sensors to gnawing larvae and temporal larval inactivity. Still, such measurements with these apparatuses can give an answer to the question whether active attack of wood-boring insects is present.
J Creemers, B Plinke, U Noldt


Application of an Ultrasound-based Instrument to Evaluate Condition of Drywood Termite Infested Timber Components
2022 - IRG/WP 22-11000
The characteristics of ultrasound waves propagation from non-destructive ultrasound-based instrument on drywood termite infested wooden components were investigated. Features of wave propagation such as time-of-flight, velocity, and peak energy on three orthogonal wooden plane (longitudinal, radial, and transversal) were studied. The wooden components used on this study came from a traditional wooden house in Pandeglang Regency, Banten Province. The basic macroscopic characteristics of wooden component were noted including fundamental physical and mechanical properties such as density, specific gravity, and dynamic MOR. SylvatestDuo was utilized to evaluate the current state of the wooden component through ultrasound wave propagation means. The wave propagation features (time-of-flight and velocity) were then translated to reconstruct residual wooden component condition via three-dimensional model. The study showed that ultrasound waves travelled at different time and velocity in the three orthogonal plane, the longitudinal plane has the highest velocity and the shortest travel period among other planes as well as highest R-squared (0.98) in the relation of time to span regression result. There were more than 50% of the wooden component were estimated to degrade due to drywood termite infestation based on the three-dimensional image reconstruction produced from the characterization of the ultrasound waves assessment results.
S Fauziyyah, L Karlinasari, D Nandika, R Wimmer