Classification of airborne laser scanning point clouds based on binomial logistic regression analysis

This article presents a newly developed procedure for the classification of airborne laser scanning (ALS) point clouds, based on binomial logistic regression analysis. By using a feature space containing a large number of adaptable geometrical parameters, this new procedure can be applied to point clouds covering different types of topography and variable point densities. Besides, the procedure can be adapted to different user requirements. A binomial logistic model is estimated for all a priori defined classes, using a training set of manually classified points. For each point, a value is calculated defining the probability that this point belongs to a certain class. The class with the highest probability will be used for the final point classification. Besides, the use of statistical methods enables a thorough model evaluation by the implementation of well-founded inference criteria. If necessary, the interpretation of these inference analyses also enables the possible definition of more sub-classes. The use of a large number of geometrical parameters is an important advantage of this procedure in comparison with current classification algorithms. It allows more user modifications for the large variety of types of ALS point clouds, while still achieving comparable classification results. It is indeed possible to evaluate parameters as degrees of freedom and remove or add parameters as a function of the type of study area. The performance of this procedure is successfully demonstrated by classifying two different ALS point sets from an urban and a rural area. Moreover, the potential of the proposed classification procedure is explored for terrestrial data.     

Interacting with the real world: design principles for intelligent systems

The last two decades in the field of artificial intelligence have clearly shown that true intelligence always requires the interaction of an agent with a real physical and social environment. The concept of embodiment that has been introduced to designate the modern approach to designing intelligence has far-reaching implications. Rather than studying computation alone, we must consider the interplay between morphology, materials, brain (control), and the environment. A number of case studies are presented, and it is demonstrated how artificial evolution and morphogenesis can be used to systematically investigate this interplay. Taking these ideas into account requires entirely novel ways of thinking, and often leads to surprising results.This work was presented, in part, at the 9th International Symposium on Artificial Life and Robotics, Oita, Japan, January 28–30, 2004     

Co-gasification of coal and wood in a dual fluidized bed gasifier

In the last decade the reduction of CO₂ emissions from fossil fuels became a worldwide topic. Co-gasification of coal and wood provides an opportunity to combine the advantages of the well-researched usage of fossil fuels such as coal with CO₂-neutral biomass. Gasification itself is a technology with many advantages. The producer gas can be used in many ways; for electric power generation in a gas engine or gas turbine, for Fischer-Tropsch synthesis of liquid fuels and also for production of gaseous products such as synthetic natural gas (bio SNG). Moreover, the use of the producer gas in fuel cells is under investigation. The mixture of coal and wood leads to the opportunity to choose the gas composition as best befits the desired process. Within this study the focus of investigation was of gasification of coal and wood in various ratios and the resulting changes in producer gas composition. Co-gasification of coal and wood leads to linear producer gas composition changes with linear changing load ratios (coal/wood). Hydrogen concentrations rise with increasing coal ratio, while CO concentrations decrease. Due to the lower sulfur and nitrogen content of wood, levels of the impurities NH₃ and H₂S in the producer gas fall with decreasing coal ratio. It is also shown that the majority of sulfur is released in the gasification zone and, therefore, no further cleaning of the flue gas is necessary. All mixture ratios, from 100 energy% to 0 energy% coal, performed well in the 100 kW dual fluidized bed gasifier. Although the gasifier was originally designed for wood, an addition of coal as fuel in industrial sized plants based on the same technology should pose no problems.     

Influence of the base and diluent methacrylate monomers on the polymerization stress and its determinants

The aim of this study was to evaluate the effect of the association between bisphenol‐A diglycidyl dimethacrylate (BisGMA) or its ethoxylated version (BisEMA) with diluents derived from the ethylene glycol dimethacrylate (EGDMA), with increasing number of ethylene glycol units (1: EGDMA, 2: DEGDMA, 3: TEGDMA, or 4: TETGDMA), or trimethylol propane trimethacrylate (TMPTMA) or 1,10‐decanediol dimethacrylate (D₃MA) on polymerization stress, volumetric shrinkage, degree of conversion, maximum rate of polymerization (Rp_max), and elastic modulus of experimental composites. BisGMA containing formulations presented lower shrinkage and stress but higher modulus and Rp_max than those containing BisEMA. TMPTMA presented the lowest stress among all diluents, as a result of lower conversion. EGDMA, DEGDMA, TEGDMA, and TETGDMA presented similar polymerization stress which was higher than the stress presented by D₃MA and TMPTMA. D₃MA presented similar conversion when copolymerized with both base monomers. The other diluents presented higher conversion when associated with BisEMA. EGDMA showed similar shrinkage compared with DEGDMA and higher than the other diluents. The lower conversion achieved by TMPTMA did not jeopardize its elastic modulus, similar to the other diluents. Despite the similar conversion presented by D₃MA in comparison with EGDMA and DEGDMA, its lower elastic modulus may limit its use. Rather than proposing new materials, this study provides a systematic evaluation of off the shelf monomers and their effects on stress development, as highlighted by the analysis of conversion, shrinkage and modulus, to aid the optimization of commercially available materials. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Toward reflective practice: A multicultural competence training model from a community mental health center.

Despite the importance of multicultural competence in clinical practice and training, there is a surprising dearth of innovative training models from fieldwork sites that would be replicable in other practicum settings. The authors illustrate a multicultural competence training model from a community mental health center that highlights the Guidelines on Multicultural Education, Training, Research, Practice, and Organization Change for Psychologists (American Psychological Association, 2003). The model focuses on providing multicultural training through two separate but linked training teams for the dual purposes of internal reflection and reflective practice. The authors conclude with a discussion of the implications of this training model for practice, research, and organizational change. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Application of UV/VIS‐Reflection Spectroscopy for Determination of the Oxidation State of Liquid Slags with High Fe3+‐Contents

This work considers the reflectivity of liquid oxides (silicates and phosphates) in the ultraviolet and visible spectral range using a reflection angle of 0°. We have developed a spectroscopic reflection method (impulse‐flash‐technique) and have investigated CaO‐FeO_n‐SiO₂ and CaO‐FeO_n‐P₂O₅ with Fe₂O₃‐contents above 32 mol‐% (FeO_1.5) at a temperature of 1400°C applying oxygen partial pressures of p_o2 = 0.001 bar up to p_o2 = 0.21 bar. The increased reflectivity in the ultraviolet spectral range is based on the very intensive electron transfer (charge transfer bands, CT) from the oxide ion (bound to the respective matrix) to the Fe³⁺‐ion. The increased reflectivities in the visible spectral range are due to d‐d‐transitions in the Fe³⁺‐ion located in Fe³⁺‐O^2? ‐complexes. This can be proven in the following way. The reflection bands in the visible range are much less pronounced than the CT‐bands in the UV range. In the slag melts, complexes with the coordination number 4, Fe³⁺(O^2?)₄, have been found predominantly. The relation between the redox state of liquid slags and their UV‐reflectance has been evaluated quantitatively. The basic investigations for recording the redox state of liquid silicates and phosphates during a running metallurgic process are part of this work. Liquid silicates and phosphates are the most important slag systems in this context.     

Microstructural characterization of the oxide scale on nitride bonded SiC-ceramics

The microstructure of the oxide scale formed at 1510 °C by oxidation of silicon nitride-bonded SiC-ceramics was studied by scanning electron microscopy (SEM). Etching by diluted HF etchants was used to help microstructural observation. This method revealed individual cristobalite crystallites as well as interfaces or interlayers between silica and non-silica phases. The ceramics–scale interface was covered by cristobalite crystallites showing that the devitrification of oxide scale begins here. Crystallites grown on SiC were smaller than those grown on binding phase. A thin HF-soluble interlayer was observed between SiC grains and cristobalite. No interlayer was found between cristobalite and oxynitride-type binding phases. The applied etching procedure gave supplementary information on the cracking, too. Partial etching by diluted HF delineated cracks in the scale. These cracks originate in the cristobalite and extend nearly perpendicularly to the substrate through the whole glassy part of the scale.     

Social identities and intergroup bias in immigrant and nonimmigrant children.

Ethnic and American identity, as well as positivity and negativity toward multiple social groups, were assessed in 392 children attending 2nd or 4th grade in various New York City neighborhoods. Children from 5 ethnic groups were recruited, including White and Black Americans, as well as recent immigrants from China, the Dominican Republic, and the former Soviet Union. For ethnic minority children, greater positivity bias (evaluating one's ingroup more positively than outgroups) was predicted by immigrant status and ethnic identity, whereas negativity bias (evaluating outgroups more negatively than one's ingroup) was associated with increased age, immigrant status, and (among 4th graders only) ethnic identity. In addition, a more central American identity was associated with less intergroup bias among ethnic minority children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Measurement of ion swarm distribution functions in miniature low-temperature co-fired ceramic ion mobility spectrometer drift tubes

Measurements of the performance of a miniature, portable 12-mm-diameter, 57-mm-length low-temperature cofired ceramic (LTCC) ion mobility spectrometer drift tube were undertaken to verify models of ion transport and determine the physical shape of the ion "swarms" in the LTCC tube. Simplified two-dimensional Gaussian models of ion swarm shape were fit to measured data to extract geometrical shape parameters. Results indicate that tube-transfer function effects that produce asymmetric ion swarms are minimized in the tube reducing temporal dispersion. Data are presented that illustrate the swarm shape as a function of gate time, electric field magnitude, and total charge in the ion swarm. Characterization and understanding of the ion transport mechanisms and effects that limit the resolution and other performance parameters of miniature IMS drift tubes is essential to the development of practical, robust, portable systems for "first responder" and homeland security missions.     

Slow repair of bulky DNA adducts along the nontranscribed strand of the human p53 gene may explain the strand bias of transversion mutations in cancers

Using UvrABC incision in combination with ligation-mediated PCR (LMPCR) we have previously shown that benzo(a)pyrene diol epoxide (BPDE) adduct formation along the nontranscribed strand of the human p53 gene is highly selective; the preferential binding sites coincide with the major mutation hotspots found in human lung cancers. Both sequence-dependent adduct formation and repair may contribute to these mutation hotspots in tumor tissues. To test this possibility, we have extended our previous studies by mapping the BPDE adduct distribution in the transcribed strand of the p53 gene and quantifying the rates of repair for individual damaged bases in exons 5, 7, and 8 for both DNA strands of this gene in normal human fibroblasts. We found that: (i) on both strands, BPDE adducts preferentially form at CpG sequences, and (ii) repair of BPDE adducts in the transcribed DNA strand is consistently faster than repair of adducts in the nontranscribed strand, while repair at the major damage hotspots (guanines at codons 157, 248 and 273) in the nontranscribed strand is two to four times slower than repair at other damage sites. These results strongly suggest that both preferential adduct formation and slow repair lead to hotspots for mutations at codons 157, 248 and 273, and that the strand bias of bulky adduct repair is primarily responsible for the strand bias of G to T transversion mutations observed in the p53 gene in human cancers.