Types Of Surface Materials Research Articles

Land Cover Classification Method Oriented to Geographic National Conditions Investigation

Abstract. Developing the project of geographic national conditions investigation is in order to obtain land cover change information which is caused by natural and human social and economic activities, and serve the information for government, enterprise and public. Land cover is an important method to describe the geographic national conditions information, which can truly reflect the land surface material type and its natural attribute. It has been contained in the content system preliminary scheme as an important portion. In this paper, it discusses and analyzes on the method and key technology, with according to the land cover content that geographic national conditions watches on. Then it evaluates the applicability of automatic classification method using in land cover information extraction, and comprehensively analyzes various extraction methods’ maximum effectiveness. Finally, it proposes a method that is based on high spatial resolution remote sensing imagery and can be used in engineering applications, which provides a reference method for geographic national conditions investigation.

Amphiphilic triblock copolymers with PEGylated hydrocarbon structures as environmentally friendly marine antifouling and fouling-release coatings

The ideal marine antifouling (AF)/fouling-release (FR) coating should be non-toxic, while effectively either resisting the attachment of marine organisms (AF) or significantly reducing their strength of attachment (FR). Many recent studies have shown that amphiphilic polymeric materials provide a promising solution to producing such coatings due to their surface dual functionality. In this work, poly(ethylene glycol) (PEG) of different molecular weights (Mw = 350, 550) was coupled to a saturated difunctional alkyl alcohol to generate amphiphilic surfactants (PEG-hydrocarbon-OH). The resulting macromolecules were then used as side chains to covalently modify a pre-synthesized PS8 K-b-P(E/B)25 K-b-PI10 K (SEBI or K3) triblock copolymer, and the final polymers were applied to glass substrata through an established multilayer surface coating technique to prepare fouling resistant coatings. The coated surfaces were characterized with AFM, XPS and NEXAFS, and evaluated in laboratory assays with two important fouling algae, Ulva linza (a green macroalga) and Navicula incerta, a biofilm-forming diatom. The results suggest that these polymer-coated surfaces undergo surface reconstruction upon changing the contact medium (polymer/air vs polymer/water), due to the preferential interfacial aggregation of the PEG segment on the surface in water. The amphiphilic polymer-coated surfaces showed promising results as both AF and FR coatings. The sample with longer PEG chain lengths (Mw = 550 g mol−1) exhibited excellent properties against both algae, highlighting the importance of the chemical structures on ultimate biological performance. Besides reporting synthesis and characterization of this new type of amphiphilic surface material, this work also provides insight into the nature of PEG/hydrocarbon amphiphilic coatings, and this understanding may help in the design of future generations of fluorine-free, environmentally friendly AF/FR polymeric coatings.

The effects of road surface and tyre deterioration on tyre/road noise emission

Tyre/road noise is becoming a more and more significant source of road traffic noise as engines become quieter. To reduce the traffic noise nuisance, low noise road surfaces and tyres have been adopted in noise sensitive areas. The durability and persistency of these low noise road surfaces and tyres are of great concerns. This study aims to quantify the effects of road and tyre deterioration on tyre/road noise. The results show that the tyre/road noise measured on five types of low noise surface material increased by 1.2–1.5dB(A) per year. The tyre rubber hardness increased by 0.6 shore-A value per month. The tyre/road noise level increased by 0.08–0.48dB(A) for every unit of shore-A value increase, depending on the road surface material. It is evident that the minimum effect of the test tyre aging on tyre/road noise measurement is 0.6dB(A) per year.

Comparative field permeability measurement of permeable pavements using ASTM C1701 and NCAT permeameter methods

Fully permeable pavement is gradually gaining support as an alternative best management practice (BMP) for stormwater runoff management. As the use of these pavements increases, a definitive test method is needed to measure hydraulic performance and to evaluate clogging, both for performance studies and for assessment of permeability for construction quality assurance and maintenance needs assessment. Two of the most commonly used permeability measurement tests for porous asphalt and pervious concrete are the National Center for Asphalt Technology (NCAT) permeameter and ASTM C1701, respectively. This study was undertaken to compare measured values for both methods in the field on a variety of permeable pavements used in current practice. The field measurements were performed using six experimental section designs with different permeable pavement surface types including pervious concrete, porous asphalt and permeable interlocking concrete pavers. Multiple measurements were performed at five locations on each pavement test section. The results showed that: (i) silicone gel is a superior sealing material to prevent water leakage compared with conventional plumbing putty; (ii) both methods (NCAT and ASTM) can effectively be used to measure the permeability of all pavement types and the surface material type will not impact the measurement precision; (iii) the permeability values measured with the ASTM method were 50–90% (75% on average) lower than those measured with the NCAT method; (iv) the larger permeameter cylinder diameter used in the ASTM method improved the reliability and reduced the variability of the measured permeability.

Advances in Design and Materials for Indoor Sports Surfaces

Natural, synthetic and combinations of natural and synthetic materials are used widely in contemporary sports surfaces which have been designed to encourage elastic deformation under load, in order to increase athletic performance and at the same time reduce the risk of injury. In response to this need, manufacturers have developed a wide variety of indoor sports flooring systems types, which are generally separated into two major categories, area-elastic sports surfaces and point-elastic sports surfaces. Area elastic sport surface structures attenuate energy by allowing deformation over a comparatively large area, where as point elastic sport surface structures deform in response to applied forces over a relatively small area, in close proximity to the point of impact. Sports surfaces can therefore be extremely complicated arrangements of materials, which contribute to a surfaces complex behaviour. The materials used in each of these surface categories, attenuate the energy applied to a surface by an athlete, in order to reduce the energy returned to the athlete. Viscoelastic materials are therefore used as synthetic shock absorbers, in order to reduce the amplitude and increase the duration of an applied shock. To understand the cushioning properties of these materials, it is necessary to consider the structural aspects of the various material combinations. It is the aim of this chapter to discuss the types of sports surface materials used, the ways in which the materials are configured and the performance standards which have been applied, in order to evaluate athletic performance and reduce the risk of injury to an athlete.

MODIS-Derived Arctic Land-Surface Temperature Trends

Across the Arctic changes in active layer, melting of glaciers and ground ice, thawing of permafrost and sequestration changes of carbon storage are driven in part by variations of land surface heat absorption, conduction and re-radiation relative to solar irradiance. We investigate Arctic land-surface temperature changes and regional variations derived by the MODIS sensors on NASA Aqua and Terra from March 2000 through July 2012. Over this decadal period we detect increase in the number of days with daytime land-surface temperature above 0℃. There are indications of increasing trends of land-surface temperature change. Regional variations of the changes in land-surface temperature likely arise due to surface material types and topography relative to the daytime variation of solar irradiance.

Validation of a Laboratory Method for Evaluating Dynamic Properties of Reconstructed Equine Racetrack Surfaces

BackgroundRacetrack surface is a risk factor for racehorse injuries and fatalities. Current research indicates that race surface mechanical properties may be influenced by material composition, moisture content, temperature, and maintenance. Race surface mechanical testing in a controlled laboratory setting would allow for objective evaluation of dynamic properties of surface and factors that affect surface behavior.ObjectiveTo develop a method for reconstruction of race surfaces in the laboratory and validate the method by comparison with racetrack measurements of dynamic surface properties.MethodsTrack-testing device (TTD) impact tests were conducted to simulate equine hoof impact on dirt and synthetic race surfaces; tests were performed both in situ (racetrack) and using laboratory reconstructions of harvested surface materials. Clegg Hammer in situ measurements were used to guide surface reconstruction in the laboratory. Dynamic surface properties were compared between in situ and laboratory settings. Relationships between racetrack TTD and Clegg Hammer measurements were analyzed using stepwise multiple linear regression.ResultsMost dynamic surface property setting differences (racetrack-laboratory) were small relative to surface material type differences (dirt-synthetic). Clegg Hammer measurements were more strongly correlated with TTD measurements on the synthetic surface than the dirt surface. On the dirt surface, Clegg Hammer decelerations were negatively correlated with TTD forces.ConclusionsLaboratory reconstruction of racetrack surfaces guided by Clegg Hammer measurements yielded TTD impact measurements similar to in situ values. The negative correlation between TTD and Clegg Hammer measurements confirms the importance of instrument mass when drawing conclusions from testing results. Lighter impact devices may be less appropriate for assessing dynamic surface properties compared to testing equipment designed to simulate hoof impact (TTD).Potential RelevanceDynamic impact properties of race surfaces can be evaluated in a laboratory setting, allowing for further study of factors affecting surface behavior under controlled conditions.

A prospective study to examine the epidemiology of methicillin-resistant Staphylococcus aureus and Clostridium difficile contamination in the general environment of three community hospitals in southern Ontario, Canada

BackgroundThe hospital environment has been suggested as playing an important role in the transmission of hospital-associated (HA) pathogens. However, studies investigating the contamination of the hospital environment with methicillin-resistant Staphylococcus aureus (MRSA) or Clostridium difficile have generally focused on point prevalence studies of only a single pathogen. Research evaluating the roles of these two pathogens, concurrently, in the general hospital environment has not been conducted. The objectives of this study were to determine the prevalence and identify risk factors associated with MRSA and C. difficile contamination in the general environment of three community hospitals, prospectively.MethodsSampling of environmental surfaces distributed over the medicine and surgical wards at each hospital was conducted once a week for four consecutive weeks. Sterile electrostatic cloths were used for environmental sampling and information regarding the surface sampled was recorded. For MRSA, air sampling was also conducted. Enrichment culture was performed and spa typing was performed for all MRSA isolates. For C. difficile, isolates were characterized by ribotyping and investigated for the presence of toxin genes by PCR. Using logistic regression, the following risk factors were examined for MRSA or C. difficile contamination: type of surface sampled, surface material, surface location, and the presence/absence of the other HA pathogen under investigation.ResultsOverall, 11.8% (n=612) and 2.4% (n=552) of surfaces were positive for MRSA and C. difficile, respectively. Based on molecular typing, five different MRSA strains and eight different C. difficile ribotypes, including ribotypes 027 (15.4%) and 078 (7.7%), were identified in the hospital environment. Results from the logistic regression model indicate that compared to computer keyboards, the following surfaces had increased odds of being contaminated with MRSA: chair backs, hand rails, isolation carts, and sofas.ConclusionsMRSA and C. difficile were identified from a variety of surfaces in the general hospital environment.Several surfaces had an increased risk of being contaminated with MRSA but further studies regarding contact rates, type of surface material, and the populations using these surfaces are warranted.

Bond Characteristics of Various NSM FRP Reinforcements in Concrete

The rehabilitation and strengthening technique using near-surface mounted (NSM) fiber-reinforced polymer (FRP) has proved to be a reliable alternative to the existing methods for deficient concrete structures. To effectively apply this method, bond characteristics at the interface need to be fully understood. This paper presents the results of the bond performance of a wide range of embedded FRP NSM reinforcements with various surface configurations, cross-sectional shapes, material types, adhesive types, and groove sizes. A total of 109 concrete specimens (with a dimension of 350×300×150 mm) were tested under direct pull-out loading configuration. It was found that both specimen sets using NSM bars treated with spirally wound and sand coating with indentation and groove displayed the best performance. Strip shape was more effective than round and square cross-sectional shapes. Higher bond strength was obtained by using carbon FRP than glass and adhesives with higher material bond strength. Increasing the groove sizes was fairly effective in improving the bond capacity. The existing bond strength models were also assessed in comparison with the test data in this paper.

Transfer, Attachment, and Formation of Biofilms by Escherichia coli O157:H7 on Meat‐Contact Surface Materials

Studies examined the effects of meat-contact material types, inoculation substrate, presence of air at the liquid-solid surface interface during incubation, and incubation substrate on the attachment/transfer and subsequent biofilm formation by Escherichia coli O157:H7 on beef carcass fabrication surface materials. Materials studied as 2 × 5 cm coupons included stainless steel, acetal, polypropylene, and high-density polyethylene. A 6-strain rifampicin-resistant E. coli O157:H7 composite was used to inoculate (6 log CFU/mL, g, or cm²) tryptic soy broth (TSB), beef fat/lean tissue homogenate (FLH), conveyor belt-runoff fluids, ground beef, or beef fat. Coupons of each material were submerged (4 °C, 30 min) in the inoculated fluids or ground beef, or placed between 2 pieces of inoculated beef fat with pressure (20 kg) applied. Attachment/transfer of the pathogen was surface material and substrate dependent, although beef fat appeared to negate differences among surface materials. Beef fat was the most effective (P < 0.05) inoculation substrate, followed by ground beef, FLH, and TSB. Incubation (15 °C, 16 d) of beef fat-inoculated coupons in a beef fat homogenate (pH 4.21) allowed the pathogen to survive and grow on coupon surfaces, with maximal biofilm formation observed between 2 and 8 d of storage and when air was present at the liquid-solid interface. The results indicated that the process of fabricating beef carcasses may be conducive to the attachment of E. coli O157:H7 onto meat-contact surfaces and subsequent biofilm formation. Furthermore, it is recommended that substrates found in beef fabrication settings, rather than laboratory culture media, be used in studies designed to investigate E. coli O157:H7 biofilm development and control in these environments. Findings of this study provide knowledge on the effect of type of beef carcass fabrication surface material, fabrication-floor fluids and residues, and incubation conditions on attachment/transfer and subsequent biofilm formation by E. coli O157:H7. The results highlight the importance of thoroughly cleaning soiled surfaces to remove all remnants of beef fat or other organic material that may harbor or protect microbial contaminants during otherwise lethal antimicrobial interventions.

Soil preparation reduces pine weevil (Hylobius abietis L.) damage on both peatland and mineral soil sites one year after planting

We studied pine weevil (Hylobius abietis (L.)) feeding damage to Norway spruce and Scots pine seedlings planted in regeneration areas located on peatlands or on mineral soil sites in Southern and Central Finland. The survey included two planting years and a total of 60 regeneration areas (40 areas on peatlands and 20 on mineral soil sites). Some sites classified as peatland were as transformed or transforming drained peatlands that also contained mineral soil on a prepared surface. The soil preparation method, type of surface material around a seedling, pine weevil, vole-induced or other damage and the health of each seedling were observed in systematically selected circular sample plots. There was slightly more pine weevil damage on peatland than on mineral soil sites. More seedlings were damaged on unprepared peat and humus than on a prepared surface. Seedlings surrounded by a prepared surface had a slightly greater risk of being gnawed by pine weevil when planted on prepared peat compared to planting on prepared mineral soil. Vole damage was observed only in one region during one year. Mounded areas had slightly less vole damage than patched areas. In order to reduce damage caused by pine weevils and voles, it is important to scarify the regeneration area properly before insecticide-treated seedlings are planted. Mounding and patching are recommended so that seedlings can be planted in mineral soil whenever possible, even in the case of peatlands.

Integration of MOSFET/MIM Structures Using a CMOS-Based Technology for pH Detection Applications with High-Sensitivity

In this work, we show that by using Metal-Insulator-Metal (MIM) structures integrated in series to the gate of submicron Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) devices, highly-sensitive and ultra-low power consumption pH sensors can be obtained. One MIM capacitor enables external polarization of the MOSFET device while a second MIM capacitor is connected to a sensing plate whose surface is whether a thick polyimide layer or the last metallization level. The electrochemical response of these surfaces to pH buffer solutions resembles that of Ion-Sensitive Field-Effect Transistor (ISFET) devices whose pH sensitivity is dependent on the type of surface material being exposed.

Development of Mechanistic–Empirical Design Procedure for Fully Permeable Pavement under Heavy Traffic

Fully permeable pavements are those in which all layers are intended to be permeable and the pavement structure serves as a reservoir to store water during storm periods to minimize the adverse effects of stormwater runoff. Fully permeable pavements are currently used primarily for light traffic (e.g., parking lots that only allow cars, not trucks). The development of fully permeable pavement designs as a potential best management practice for stormwater management in areas that carry heavy truck traffic is of significant interest. Results are presented from one phase of a project to develop mechanistic–empirical design procedures for fully permeable pavement designs that will carry heavy vehicles operating primarily at slow speeds (e.g., in maintenance yards, parking lots, streets, and highway shoulders). Mechanistic–empirical computer modeling of the structural designs was performed for three types of surface material (open-graded asphalt, open-graded concrete, and concrete slabs with cast drainage), considering different traffic loading based on typical California highway truck traffic, different traffic speeds, and several typical California climate regions, as well as materials properties developed from laboratory testing. A preliminary design method and preliminary design charts that considered both hydraulic and structural performance were developed; some examples of their use are provided. The mechanistic–empirical approach used in this project for the development of fully permeable pavement designs could increase the speed of development and implementation of this technology.

Manure and Runoff Water Quality from Feedlots as Affected by Diet and Pen Surface

Environmental management of confined animal feeding operations is closely regulated. Hence, understanding management practices that affect nutrient outputs and the potential risk of transport in the environment is of importance. The objective of this research was to evaluate the impact of feeding corn-based wet distillers grains plus solubles (WDGS) and the type of pen surface material on manure nutrient composition and runoff water quality. Rainfall simulations were conducted at an experimental feedyard that contained soil and fly ash surfaced pens. Two diets, steam-flaked corn (SFC) and 30% WDGS, were fed to cattle on each surface type. Diets containing WDGS resulted in greater manure nitrogen (N) and phosphorus (P) concentrations than SFC diets. Runoff volumes were significantly higher from soil pens where WDGS diets were fed. Runoff volumes were consistent for fly ash pens; however, there was a 3-fold difference between soil surfaced pens, indicating great variability between soil surfaced pens. Feeding WDGS increased soluble reactive P (SRP) concentrations in runoff water by 38% and total P concentrations by 27% compared to SFC. This increase in P runoff concentrations as a result of feeding WDGS was expected, as manure WEP concentrations were greater in pens where WDGS was part of the diet. Pen surfaces with fly ash resulted in increased total P and ammonium-N (NH4-N) concentrations in runoff water. Mass losses of SRP, total P, NH4-N, and total Kjeldahl N (TKN) were highest from soil surfaced pens in which cattle were fed WDGS. While manure nutrient concentration can be an excellent indicator of the potential of nutrient runoff, hydrological properties can be the single most important factor in actually transporting nutrients offsite.

Spatial distribution of tropical wetlands in Central Brazil as influenced by geological and geomorphological settings

Tropical wetlands in Central Brazil are located in savanna areas and are made up of more terrestrial-type wetlands – campo limpo úmido (grassland-type savanna), campo sujo úmido (shrub-type savanna), mata galeria (riverine forest); as well as more aquatic-type wetlands – vereda (valley-side marsh with palm groves of Mauritia flexuosa), várzea (backswamp), lake, and river. They are regulated by a seasonal climatic regime characterized by a wet-rainy season from October to March and then followed by a dry season. Underground water is abundant and rivers frequently overflow during the rainy season. Many of these wetlands which are protected by law are significant regulators of water quality. In order to predict tropical wetland function and draw up environmental management policies, it is important to understand how abiotic and biotic factors influence tropical wetland origin and spatial distribution. In this large-scale study we set out to investigate the influence that geological and geormorphological settings, i.e. geological substrates and geomorphological units, have on the spatial distribution of tropical wetlands in Central Brazil. Two watersheds, the Caiapó and Piracanjuba, were selected in order to carry out the study. They present different types of rock and unconsolidated surface materials. Planation surface, escarpment and steep slope, gentle slope, and aggradation are the dominant geomorphological units in the watersheds. Principal component analysis was conducted in order to determine the influence of the selected abiotic variables on the spatial distribution of tropical wetlands. The study showed that the presence of sedimentary and low-grade metamorphic rocks and planation surface strongly influence the spatial distribution of the more terrestrial-type wetlands. Geological and geomorphological settings explain about 60% of the variability in the spatial distribution of these wetland types. No clear effect of the abiotic variables selected was observed on the more aquatic-type wetlands. An association between stratified layers or planar geological surfaces, groundwater discharge zones, and slope breaks is suggested to explain the influence of the geological and geomorphological settings on the wetlands under review. The study demonstrated the importance of considering abiotic factors, not usually included in classification schemes, to further understand the spatial distribution of tropical wetlands.

Evaluation of moisture buffering capacity of interior surface materials and furniture in a full-scale experimental investigation

Moisture buffering (MB) phenomena exhibited by hygroscopic materials, such as interior finishing or furnishing, can reduce indoor humidity variation, thus improving indoor conditions and save energy consumed by the mechanical system for humidification or dehumidification. In full-scale experiments, the moisture buffering effect for an entire room is typically evaluated by the reduction of indoor relative humidity (RH) variation. In this study, a new approach to quantitatively evaluate the moisture buffering capacity of hygroscopic materials, namely the maximum accumulated moisture buffering value (MAMBV), is developed based on the moisture balance established in a full-scale experimental investigation. This value represents the maximum amount of moisture buffered by the hygroscopic materials. The impact of ventilation rate, moisture generation protocol, and addition of furniture on two types of interior surface materials, i.e. uncoated gypsum board and wood paneling, are evaluated using the MAMBV index.

Importance of Surface Conditions for Spacecraft Charging

Abstract : Spacecraft charging is determined by the ambient plasma environment and the surface properties. Whereas the ambient plasma environment is measured in-situ and in real time, the surface property data rely on measurements conducted previously in the laboratory and empirical formulae derived from the laboratory measurements. This note addresses the importance of surface conditions in determining the spacecraft surface potentials. For example, the surface smoothness, thickness, surface composition, and surface contamination are important factors that govern the current balance at equilibrium and the onset of spacecraft charging. These parameters of surface conditions can also greatly influence the accuracy of model calculations of the spacecraft potential. We will provide supporting data to illustrate the main points and to make the case. For spacecraft design, it is inadequate to look up published tables of the coefficients for a given type of surface material. It is necessary to measure the secondary electron coefficient, for example, of an actual piece of the material, because the thickness, smoothness, and surface composition, etc. do matter. In the harsh space environment, surface conditions can also change gradually as a result of the unceasing bombardment by the incoming electrons and ions. All these factors pose uncertainty to spacecraft charging.

Microbial biofilm detection on food contact surfaces by macro-scale fluorescence imaging

Hyperspectral fluorescence imaging methods were utilized to evaluate the potential detection of pathogenic bacterial biofilm formations on five types of food contact surface materials: stainless steel, high-density polyethylene (HDPE), plastic laminate (Formica), and two variations of polished granite. The main objective of this study was to determine a minimal number of spectral fluorescence bands suitable for detecting microbial biofilms on surfaces commonly used to process and handle food. Spots of biofilm growth were produced on sample surfaces by spot-inoculations of pathogenic Escherichia coli O157:H7 and Salmonella followed by room temperature storage for 3 days. Subsequently, hyperspectral fluorescence images were acquired from 421 to 700 nm using ultraviolet-A excitation. Both E. coli O157:H7 and Salmonella biofilms emitted fluorescence predominantly in the blue to green wavelengths with emission maxima at approximately 480 nm. A single-band image at 559 nm was able to detect the biofilm spots on stainless steel. On HDPE and granite, algorithms using different two-band ratios provided better separation of the biofilm spots from background areas than any single-band images did. The biofilm spots on stainless steel, HDPE, and granite could be detected with overall detection rate of 95%. On Formica, too many false positives were present to accurately determine an effective biofilm detection rate. This may have been due to the lower cell population density that was observed for the biofilm spots grown on Formica (approximately 4.3–6.4 log cfu cm −2) as compared to the other surfaces. These findings can be incorporated into developing portable hand-held imaging devices for sanitation inspection of food processing surfaces.

Genetic adaptation of Streptococcus mutans during biofilm formation on different types of surfaces

BackgroundAdhesion and successful colonization of bacteria onto solid surfaces play a key role in biofilm formation. The initial adhesion and the colonization of bacteria may differ between the various types of surfaces found in oral cavity. Therefore, it is conceivable that diverse biofilms are developed on those various surfaces. The aim of the study was to investigate the molecular modifications occurring during in vitro biofilm development of Streptococcus mutans UA159 on several different dental surfaces.ResultsGrowth analysis of the immobilized bacterial populations generated on the different surfaces shows that the bacteria constructed a more confluent and thick biofilms on a hydroxyapatite surface compared to the other tested surfaces. Using DNA-microarray technology we identified the differentially expressed genes of S. mutans, reflecting the physiological state of biofilms formed on the different biomaterials tested. Eight selected genes were further analyzed by real time RT-PCR. To further determine the impact of the tested material surfaces on the physiology of the bacteria, we tested the secretion of AI-2 signal by S. mutans embedded on those biofilms. Comparative transcriptome analyses indicated on changes in the S. mutans genome in biofilms formed onto different types of surfaces and enabled us to identify genes most differentially expressed on those surfaces. In addition, the levels of autoinducer-2 in biofilms from the various tested surfaces were different.ConclusionsOur results demonstrate that gene expression of S. mutans differs in biofilms formed on tested surfaces, which manifest the physiological state of bacteria influenced by the type of surface material they accumulate onto. Moreover, the stressful circumstances of adjustment to the surface may persist in the bacteria enhancing intercellular signaling and surface dependent biofilm formation.

An effective exploration approach to simultaneous mapping and surface material–type identification of complex three‐dimensional environments

AbstractThis paper presents an integrated exploration approach for geometric mapping and surface material–type identification of complex three‐dimensional (3D) environments using a six‐degree‐of‐freedom industrial robot manipulator. Maps of the surface geometry with the surface material type identified are required for an autonomous robotic system to perform operations in steel bridge maintenance. The proposed approach utilizes information theory to enable multiobjective exploration while new 3D geometric and surface‐type data are fused via probabilistic updates. It is verified that the integrated approach enables the robotic system to perform exploration and surface inspection in real‐world environments. © 2009 Wiley Periodicals, Inc.