Inspection Of Walls Research Articles

CROMSCI: development of a climbing robot with negative pressure adhesion for inspections

Purpose – The non‐destructive inspection of large concrete walls (e.g. dams, bridge pylons) with autonomous systems is still an unsolved problem. One of the main difficulties is to develop a very flexible platform, which is able to move and inspect horizontal and vertical surfaces safely, and which is fast and cost‐efficient. The purpose of this paper is to present a climbing robot designed with these attributes in mind.

Development of an omni‐directional mobile robot using traveling waves based on snail locomotion

PurposeThe snail moves by propagating traveling waves from tail to head. If it is possible to propagate a traveling wave in many directions, an omni‐directional mobile robot could be realized. The purpose of this paper is to develop an omni‐directional mobile robot using the locomotion mechanism of the snail and to study the basic properties of the robot.Design/methodology/approachA unit for mobile robot was developed to generate the traveling wave based on the snail. The omni‐directional mobile robot is composed of eight units arranged in a circular shape and each abutting unit is connected by a spring. The robot generates a traveling wave by elongation and contraction of the units and realizes an omni‐directional locomotion.FindingsIt was confirmed that the robot moves using the traveling wave locomotion. Furthermore, the locomotion experiment confirmed that the robot moved in the expected direction with reasonable accuracy.Originality/valueThis paper proposes a new omni‐directional mobile mechanism using traveling wave based on a snail locomotion. Since the locomotion mechanism of the snail involves moving a larger area than is the case with other creatures, it is able to move not only on irregular ground such as swamps, but also on walls and ceilings. Hence, it is thought that this robot could be applied to the inspection of walls.

Subcutaneous hydration

EDITOR: Subcutaneous hydration, also called hypodermoclysis, is commonly used in elderly patients. We report a case of colonic perforation in order to raise awareness that this technique is not fully harmless. Case report An 86-yr-old lean (45 kg, 165 cm) female was admitted to our emergency department with abdominal pain and vomiting. Her past medical history included untreated hypertension and advanced dementia. She was living in an institution. Symptoms had begun 1 week previously with difficulties in feeding and drinking. Parenteral hydration was started with a subcutaneous infusion of normal saline via a 24-G short needle in the right inferior quadrant of the abdomen. No immediate complication was reported during the puncture. Confusion developed a few hours later and bilious vomiting appeared the day after. She was then transferred to our institution for investigation. Pain and diffuse tenderness were the only abnormalities reported at physical examination. Abdominal wall inspection noted a needle puncture hole without fluid loss or inflammation in the right iliac fossa. Neither her general nor haemodynamic status were altered. Temperature was 36.3°C. Acute renal failure was the only observed biological abnormality. Abdominal computed tomography (CT) scan showed subcutaneous emphysema, global intestinal distension and pneumoperitoneum (Fig. 1). Punctiform caecal perforation close to the skin needle site was discovered during a laparotomy and led to caecal resection with ileostomy and colostomy. General peritonitis required amoxicillin/clavulanic acid administration. The patient fully recovered and was returned to her institution 2 weeks later.Figure 1: Abdominal computed tomography (CT) scan with contrast injection shows subcutaneous emphysema (arrow) and pneumoperitoneum.Discussion Hydration and electrolyte balance in the elderly is a real challenge. Management in institutions adds the issues of a poor medical and nursing environment and sometimes non-cooperative patients. A nasogastric tube is often not well tolerated. Whereas intravenous (i.v.) catheterization is considered as invasive, the subcutaneous space is considered as a useful route for fluid diffusion or infusion. Compromised peripheral venous vascularization can be another indication for hypodermoclysis as an alternative to central venous access. Evidence-based studies are lacking [1]. Three main sites can be considered: arms or legs are the safest choices, but are limited by induced discomfort or unintentional removal during movement. Abdomen puncture is an alternative. The left iliac fossa should be chosen because at that point there is a maximal distance between the colon and the abdominal wall. Careful aspiration is the rule before injection so as to detect vessel injury or air aspiration. Only one case of major infection has been reported [2]. Obesity or insulin injection does not increase the risk of iatrogenic complications [3]. In the same way no colonic perforation during ascites paracentesis has been described. Colonic damage occurs mostly from inside to outside during endoscopic procedures or after foreign body ingestion. Prognosis depends on treatment delay [4] because of peritonitis. Perforation could be favoured by a thin and slim abdominal wall musculature related to old age. The CT scan findings are easily explained by the mechanism of colonic injury. Intestinal distension is explained by the reflex ileus encountered during peritonitis. More interesting is the presence of subcutaneous emphysema related to the diffusion of the pneumoperitoneum through the needle track. To conclude, physicians should be alert to the possibility of potential life-threatening complications linked with the subcutaneous route. Nevertheless, owing to the favourable benefit/risk balance hypodermoclysis seems a good alternative to i.v. or oral rehydratation in the elderly as long as basic safety rules are respected.

Diversidade, distribuição e abundância de flebotomíneos (Diptera: Psychodidae) no Paraná

Due to the spread of Visceral leishmaniasis in Brazilian territory, this research was undertaken with the objective to identify the sandfly fauna and aspects of the species behavior in forest and anthropic environments in Paraná State, Brazil. The sandfly captures were sporadically carried out in 37 municipalities of the Paraná state, during the period from March 2004 to November 2005. Each municipality was once visited, when Falcão traps were installed during three consecutive nights in forested fragments and anthropic environments; captures with Shannon traps installed in forests and edge of forests, inspection of walls and electric aspiration in domiciles and forested areas were sporadically undertaken. The data analysis was based on estimates of frequency and abundance of the species, by five native landscapes. A total of 38,662 specimens belonging to 23 species were captured. Nyssomyia neivai (Pinto) (75.6%), Ny. whitmani (Antunes & Coutinho) (10.1%), Migonemyia migonei (França) (7.8%), Expapillata firmatoi (Barreto et al.) (2.1%) and Pintomyia fischeri (Pinto) (1.6%) together constituted 97.2% of the phlebotomine collected. High frequencies of sand flies were found in forests, henhouses, pig-pens and domiciles. The three most frequent species have been implicated in transmission of tegumentary leishmaniasis in Paraná and in the Brazilian Southeastern and Southern Regions. Lutzomyia longipalpis (Lutz & Neiva), the visceral leishmaniasis vector, was not found, however Lutzomyia gaminariai (Cordero et al.), female of which is similar to that of Lu. longipalpis was captured, raising the need to investigate its behavior, including as regard to the vectorial competence.

Erroneous Design Assumptions and Construction Defects in a Thin Stone Facade System

Abstract During a routine close-up facade inspection of the exterior walls of a 15-year-old, 31-story office building, a loose 30-mm thick granite panel was discovered. Initially, it was believed that this movement was due to the location of the anchorages relative to the panel geometry. A more thorough examination of the panel was performed by inspecting the panel attachment from the interior of the building. This inspection revealed that one of the two epoxied wind load anchors had failed. An extensive investigation of the granite facade panels, including additional close-up exterior and interior inspections, structural analyses, and testing, was undertaken. Interior examinations revealed construction defects in the epoxied anchors. In addition, the structural analyses indicated a flaw in the original design that affected certain panels in high wind load zones. Repairs were designed to address the design and construction deficiencies. Supplemental panel anchorages were installed from the exterior of the building, thereby minimizing disruptions to building occupants. While the implemented panel repairs can be identified at close range, they are imperceptible from publicly accessible vantage points.

Evaluation and management of Cushing syndrome in cases of negative sellar magnetic resonance imaging

✓ The treatment of patients with Cushing disease and without magnetic resonance (MR) imaging evidence of Cushing disease (that is, negative MR imaging) is discussed in this paper. Magnetic resonance imaging is the diagnostic modality of choice in Cushing disease, but in up to 40% of these patients negative imaging can be caused by tumor-related factors and limitations in imaging techniques. In cases in which the MR imaging is negative, it is critical to make sure that the diagnosis of Cushing disease is correct. This can be accomplished by performing a complete laboratory and imaging workup, including dexamethasone suppression tests, imaging of the adrenal glands, and inferior petrosal sinus sampling when appropriate. If these evaluations suggest a pituitary source of the hypercortisolemia, then transsphenoidal surgery remains the treatment of choice. The authors favor the endoscopic approach because it gives a wider and more magnified view of the sella and allows inspection of the medial cavernous sinus walls. Radiosurgery is an effective treatment option in patients with persistent Cushing disease. When a target cannot be found on MR imaging, one can target the entire sellar region with radiosurgery.

Evaluation and management of Cushing syndrome in cases of negative sellar magnetic resonance imaging

The treatment of patients with Cushing disease and without magnetic resonance (MR) imaging evidence of Cushing disease (that is, negative MR imaging) is discussed in this paper. Magnetic resonance imaging is the diagnostic modality of choice in Cushing disease, but in up to 40% of these patients negative imaging can be caused by tumor-related factors and limitations in imaging techniques. In cases in which the MR imaging is negative, it is critical to make sure that the diagnosis of Cushing disease is correct. This can be accomplished by performing a complete laboratory and imaging workup, including dexamethasone suppression tests, imaging of the adrenal glands, and inferior petrosal sinus sampling when appropriate. If these evaluations suggest a pituitary source of the hypercortisolemia, then transsphenoidal surgery remains the treatment of choice. The authors favor the endoscopic approach because it gives a wider and more magnified view of the sella and allows inspection of the medial cavernous sinus walls. Radiosurgery is an effective treatment option in patients with persistent Cushing disease. When a target cannot be found on MR imaging, one can target the entire sellar region with radiosurgery.

FDTD simulations for ground penetrating radar in urban applications

Ground penetrating radar (GPR) is a very important tool for urban investigations. We introduce a finite difference time domain (FDTD) method to solve Maxwell's equations when the dispersive earth medium can be simulated. We give an iterative method for electrical displacement and magnetic field in a Debye medium, and a method to compute electric field from electrical displacement. The physical parameters are used only in calculating the electric field. The examples demonstrate that the electromagnetic wave in the dispersive medium attenuates very fast and the measured signals are very weak. The cavity detection and the tunnel wall inspection are numerically proven to be possible and effective.

ICONE15-10200 INVESTIGATION OF THE FLOW IN ORIFICE DOWNSTREAM AFFECTING FLOW ACCELERATED CORROSION

Flow Accelerated Corrosion (FAC) is a main cause of pipe wall thinning phenomena in nuclear and thermal power plants, which requires considerable care and prediction since it has a potential of catastrophic pipe rupture. In this study, flow visualization experiments and numerical calculations were conducted to investigate the flow characteristics affecting FAC. Among various piping elements susceptible to FAC, flow in orifice downstream, with pipe diameter contraction ratio of 0.6, was chosen as the target in this report. Turbulent kinetic energy was found out to be a presumable factor to affect FAC, since its profile trend nearly matched with that of pipe wall thinning data at actual plant piping. Reattachment points of flow separation, created at orifice downstream, will be, at the utmost, 2.5 times of the pipe diameter (2.5D) with plant piping system condition, although they gradually shift towards downstream with the increase of Reynolds number. From this result, for pipe wall inspection region at orifice downstream, 3D would be the conservative length enough, with emphasized inspection around the half length of reattachment point, presumed to be the most susceptible area for FAC.

Liquid fuel microcombustor using microfabricated multiplexed electrospray sources

The use of hydrocarbons is very appealing for the realization of high energy density power sources, so long as the fuel can be stored in the liquid phase. As a result, except for the most volatile hydrocarbons, a miniaturized combustor must rely on a good design of the fuel atomizer, which should yield small, rapidly evaporating droplets to generate the fuel vapor promptly, mix it with the oxidizer and subsequently burn it with the attending heat release. To achieve this goal, we relied on the use of multiplexed electrosprays and a catalytic reactor for fuel conversion consisting of a pack of catalyst impregnated meshes (Microliths ®). Fuel dispersion was achieved by microfabricating the fuel distributor in Si using deep reactive ion etching. Tests were performed using JP-8 as the liquid fuel. Preliminary experiments in a 0.8 cm 3 optically accessible combustor, enabling the measurements of droplet size and velocity, revealed that the spreading of the electrospray by Coulombic repulsion is the phenomenon controlling the volume of the mixing/evaporation chamber. Droplet evaporation occurs in the thin (Peclet number dependent) thermal layer preceding the catalytic section of the combustor. Subsequent system optimization in a fully ceramic combustor yielded a volumetric heat release rate as large as 270 MW/m 3, a value that is of the same order as that of conventional gas turbines. The small overall combustor volume, at only 0.22 cm 3, suggests that the large volumetric energy density was achieved despite the device large surface-to-volume ratio and attending heat losses. The fuel was fully oxidized, with CO/CO 2 ratios well under 1% over a range of equivalence ratios. Inspection of the combustor inner walls after operating continuously for 10 h, revealed no traces of deposits. The design has the potential of being scaled either up or down, depending on power needs.

Ex vivo study of the efficacy of H‐files and rotary Ni–Ti instruments to remove gutta‐percha and four types of sealer

To compare the efficacy of ProFile rotary Nickel-Titanium (Ni-Ti) instruments and Hedstroem-files (H-files) combined with Gates-Glidden (GG) drills during removal of gutta-percha root fillings used in combination with one of the four representative sealers. Forty-eight single-rooted human teeth, with fully formed apices and straight root canals were used. The root canals were accessed and instrumented using a stepback technique with H-files. They were randomly assigned to four groups and subsequently filled with a combination of lateral and vertical condensation of gutta-percha and one of the following sealers: Roth 811, AH26, Endion and Roekoseal. The root fillings were removed 1 year later, using either H-files in combination with GG drills or the ProFile Ni-Ti system. Teeth were then grooved longitudinally and split. The amount of gutta-percha and sealer remaining on the root canal walls was traced and scored visually with the aid of a stereomicroscope. The scores were analysed and statistically compared with the Kruskal-Wallis test between the ProFile and H-file groups, as well as among the four sealer subgroups. Two samples from each group were studied under the scanning electron microscope to enhance inspection of canal walls and remaining material. Sealer remnants were observed with both techniques mainly in the middle and apical third of the root canal. The ProFile system and the H-files were associated with similar amounts of remaining filling material (P > 0.05). In the cervical third of the root canal all sealer remnants were removed with both techniques. In the middle and apical third AH26 was associated with a statistically significant greater quantity of remnants on the root canal walls with both removal techniques (P < 0.05). Endion, Roth 811 and Roekoseal were associated with approximately the same amount of filling material in the middle third of the root canal (P > 0.05), whereas in the apical third Endion was associated with significantly more remnants of filling material than the other two sealers with either ProFile or H-files (P < 0.05). None of the methods used for the removal of root fillings was totally effective, especially in the apical third of the root canal.

Non-contact intrawall penetrating radar for heritage survey: the search of the ‘Battle of Anghiari’ by Leonardo da Vinci

In this paper a high-frequency large-bandwidth synthetic aperture penetrating radar intended for the inspection of masonry walls, and its application to intrawall investigation of an important Heritage structure in Florence, Italy, are described. The radar system has been conceived and designed for non-contact operation, in particular for allowing walls covered by paintings to be inspected avoiding damages to the surface artworks. The radar signal was a Continuous-Wave Step-Frequency (CW-SF) waveform, sampling a 4 GHz bandwidth at 10 GHz center frequency, thus providing relatively high resolution images of the investigated structures. Cross-range resolution is provided by applying a synthetic aperture approach, obtained by mechanically moving the radar antenna along a 2 m length aperture. In order to assess the radar performances and its detection capability, laboratory tests on masonry facilities were preliminarily performed. Finally, an extensive measurement campaign was carried out on a famous 16th century structure: the ‘Hall of 500’, in Palazzo Vecchio (Old Palace), in Florence (Italy). This investigation was aimed at finding evidence of possible discontinuities in the masonry walls, where fragments of the famous fresco the ‘Battle of Anghiari’ by Leonardo da Vinci could be hidden.

Development of a safety/support unit for climbing service robots

Building maintenance tasks are labour-intensive and of a high-risk nature. Workers are often required to carry out the maintenance work, such as wall inspection and cleaning, in mid-air and at high altitudes. In order to enhance the work safety and efficiency, many research projects have been carried out worldwide to investigate the use of climbing service robots for automating these hazardous tasks. As part of each system, most of these service robots do require a safety/support unit to provide an external power source and also a safety mechanism to prevent the robot from falling in the case of accidents. In addition, the safety/support unit is also used as a control console to provide the human operator with a constant communication link with the robot for monitoring and controlling the remote maintenance operations. In order to ensure high reliability and safety of service, it is essential to have a tight integration between the robot and the safety/support system. In this paper, some of the important issues for designing the safety/support unit are discussed. Also, a fuzzy neural technique for controlling the swing and vibration of the safety wire rope is described.

El Niño water leaks identify rooms with concealed mould growth and degraded indoor air quality

Residence hall rooms with and without a water leakage history during 1997–1998 El Niño storms were studied in 1999–2001 by destructive inspection (opening) of exterior walls for concealed mould growth and by sampling of room air for culturable fungi. Compared with air in non-leaky rooms and with outdoor air, rooms with 1997–1998 severe water leakages were found to have approximately an order of magnitude increase in levels of airborne Penicillium spp., e.g., P. chrysogenum , P. crustosum and P. aurantiogriseum . The rank order of pooled fungal taxa from leaky rooms was significantly different from the kinds of fungi found in outdoor air. However, the airborne fungi in non-leaky rooms resembled the fungi present in outdoor air. The surface area of visible mould growth concealed in wall cavities of exterior walls was at least 10-fold higher in leaky than in non-leaky rooms. This study showed that inspection for water leaks is of central importance in the evaluation of buildings for mould damage. In addition, the study showed that spores from hidden mould growth could enter rooms in sufficient quantity to significantly affect the rank order profile of taxa in the indoor air.

Development of an image recognition system for RFX first wall maintenance

Since the beginning of the machine operation a remote handling system (RHS) has been used to carry out maintenance tasks inside the RFX vacuum vessel, such as tile replacement, first wall inspection and graphite fragment removal. In order to speed up the tile replacement operations and to increase their reliability and safety, it was envisaged to develop a monoscopic vision system capable of recognizing the tile clamping system components on which the end-effector must act to dismount/mount the tiles. The vision system has now been realized and it is described in the paper along with end-effector modifications and executed tests.

Nine New Painted Rock Art Sites from East Timor in the Context of the Western Pacific Region

Few rock art sites are known for the islands of Wallacea. This paper reports nine new painted rock art sites located in East Timor during archaeological reconnaissance in 2000 to 2001; bringing the total number of painted rock art sites in East Timor to 15. Both the new and previously known rock art sites in East Timor are reviewed in the context of painted rock art elsewhere in the western Pacific region. They are also evaluated in terms of the criteria used by Ballard (1992) to define the "Austronesian painting tradition" and the relationship between the art, topography, and language groups for the new sites is described. Motif content, motif placement within the sites, and design elements are compared in a preliminary fashion with that of other painting sites known from East Timor and the western Pacific. The East Timor sites are conformable with Austronesian-painted rock art sites elsewhere although they display some features that appear to be locally or regionally distinctive. It is likely that with systematic survey, and thorough inspection of cave and shelter walls, many more sites will be found in East Timor and elsewhere in Island Southeast Asia. The faded and deteriorated condition of many of the East Timor paintings indicates that recording should be undertaken with some urgency.

Experimental investigation on the thermal stability of some new zero ODP refrigerants

Five zero ODP (ozone depletion potential) hydro-fluorocarbon refrigerants (HFC-23, HFC-143a, HFC-227ea, HFC-236fa, HFC-245fa) were tested to define their maximum usable temperature and their thermal degradation threshold. Pyrolysis is detected (a) as a pressure change at constant temperature and volume; (b) as a departure of the vapour pressure curve of the heated fluid from that of the original substance. Visual inspection of the vessel walls and fluid chemical analysis complement the method. The minimum detectable degradation rate is believed to be less than 1% in 50 h. All the fluids exhibit a variable, but excellent thermal stability up to the following temperatures at which no decomposition was observable in 50–100 h: 425 °C for HFC-227ea, 400 °C for HFC-23 and HFC-236fa, 350 °C for HFC-143a and 300 °C for HFC-245fa. Clear degradation signs were observed at temperatures 25–50 °C higher. Most of the fluids heated up to their thermal stability threshold exhibited an induction period of 5–50 h in which no decomposition was detectable but after which an observable degradation started. For a given fluid such period decreases at increasing temperatures. The use of fluids in a cyclic process in which the working medium permanence at the top temperature is very brief could take advantage of this behaviour with a reduction in degradation rates or with an increase in the limiting temperature. The influence of the decomposition products on the functionality of a thermodynamic power cycle was investigated by means of an appropriate computer code. The working fluid was assumed to be a binary mixture with 1 to 3% concentration of a light decomposition product of the methane series. Chemical species such as CH 4 and CF4 with a critical temperature much lower than that of the base fluid strongly affect the cycle configuration. On the contrary species with critical temperatures closer to that of the base fluid such as CH 3F, CH 2F 2 or CHF 3 influence only marginally the cycle performance. In general a small concentration of decomposition products in the working medium is likely to be acceptable without noticeable drawbacks.

High resolution optical sensor for the inspection of engine cylinder walls

Summary The inspection of an engine cylinder wall is an important industrial application for optical sensors. This task is an example, where a 3-D characterization of the microstructure is needed to obtain a full functional surface description. Recently several approaches have been made to solve this problem. In this paper a short comparison about the different approaches is given and a new highly resolving sensor is presented. This sensor enables a spatial resolution of 1 μm, a vertical resolution of up to 1 nm, and is realized in a very compact housing. Measurements are given which demonstrate the progress in this application field.

Topograph for inspection of engine cylinder walls

The microstructural inspection of engine cylinder walls is an important task for quality management in the automotive industry. Until recently, mainly tactile methods were used for this purpose. We present an optical instrument based on microscopic fringe projection that permits fast, reliable, and nondestructive measurements of microstructure. The field of view is 0.8 mm x 1.2 mm, with a spatial sampling of 1100 x 700 pixels. In contrast to conventional tactile sensors, the optical method provides fast in situ three-dimensional surface characterizations that provide more information about the surface than do line profiles. Measurements are presented, and advantages of this instrument for characterization of a surface are discussed.

Reproductive Biology of the Aquatic Salamander Amphiuma tridactylum in Louisiana

Reproductive Biology of the Aquatic Salamander Amphiuma tridactylum in Louisiana