Combining an Angle Criterion with Voxelization and the Flying Voxel Method in Reconstructing Building Models from LiDAR Data

Abstract: Traditional documentation capabilities of laser scanning technology can be further exploited for urban modeling through the transformation of resulting point clouds into solid models compatible for computational analysis. This article introduces such a technique through the combination of an angle criterion and voxelization. As part of that, a k‐nearest neighbor (kNN) searching algorithm is implemented using a predefined number of kNN points combined with a maximum radius of the neighborhood, something not previously implemented. From this sample, points are categorized as boundary or interior points based on an angle criterion. Façade features are determined based on underlying vertical and horizontal grid voxels of the feature boundaries by a grid clustering technique. The complete building model involving all full voxels is generated by employing the Flying Voxel method to relabel voxels that are inside openings or outside the façade as empty voxels. Experimental results on three different buildings, using four distinct sampling densities showed successful detection of all openings, reconstruction of all building façades, and automatic filling of all improper holes. The maximum nodal displacement divergence was 1.6% compared to manually generated meshes from measured drawings. This fully automated approach rivals processing times of other techniques with the distinct advantage of extracting more boundary points, especially in less dense data sets (<175 points/m²), which may enable its more rapid exploitation of aerial laser scanning data and ultimately preclude needing a priori knowledge.     

Robotic System for Handling Infectious Clinical and Pre-Clinical Serum Samples

The Bioanalytical Laboratory at the Schering-Plough Research Institute is a service laboratory which performs drug level measurements in serum in support of pre-clinical toxicological tests, as well as human clinical trials for anti-viral compounds. A new robot system for the laboratory had two external constraints put on it, besides those typical for a robotic system: since it handled infectious serum samples, it needed to be contained within a biosafety cabinet, and all data handling and labeling were subject to regulatory oversight. The result is a robot cell consisting of a large custom biological safety hood with an integrated track mounted robot, refrigerated storage, mixing, 2-D bar code reading, and automated pipetting. In addition to the material handling hardware, sample labeling software was developed for use at sample collection sites within Schering-Plough, and at external contract laboratories.     

Acceleration of Anti‐Markovnikov Hydroamination in the Synthesis of an Active Pharmaceutical Ingredient

Slow chemical reactions are a big challenge in the modern pharmaceutical industry. Their accelerations together with the introduction of continuous manufacturing modes are major drivers for future development. One example reaction is hydroamination, a reaction between unsaturated hydrocarbons and amines. Such a reaction type is the main focus of this work. More precisely, the anti‐Markovnikov hydroamination reaction between cis/trans 9H‐thioxanthene‐2‐chloro‐9‐(2‐propenylidene)‐(9CI) and 1‐(2‐hydroxyethyl)piperazine (HEP) is investigated in detail. It has been traditionally performed in toluene with a huge excess of HEP and reaction times of up to 24 h. Acceleration of the reaction from 24 down to 4 h is achieved by switching from batch operation mode in toluene to either solvent‐free batch mode or microwave‐assisted hydroamination with tetrahydrofuran as a solvent.     

Reasoning Processes in Propositional Logic

We conducted a computer-based psychological experiment in which a random mix of 40 tautologies and 40 non-tautologies were presented to the participants, who were asked to determine which ones of the formulas were tautologies. The participants were eight university students in computer science who had received tuition in propositional logic. The formulas appeared one by one, a time-limit of 45 s applied to each formula and no aids were allowed. For each formula we recorded the proportion of the participants who classified the formula correctly before timeout (accuracy) and the mean response time among those participants (latency). We propose a new proof formalism for modeling propositional reasoning with bounded cognitive resources. It models declarative memory, visual memory, working memory, and procedural memory according to the memory model of Atkinson and Shiffrin and reasoning processes according to the model of Newell and Simon. We also define two particular proof systems, T and NT, for showing propositional formulas to be tautologies and non-tautologies, respectively. The accuracy was found to be higher for non-tautologies than for tautologies (p < .0001). For tautologies the correlation between latency and minimum proof length in T was .89 and for non-tautologies the correlation between latency and minimum proof length in NT was .87.     

Non-aqueous stabilized suspensions of BaZr0.85Y0.15O3−δ proton conducting electrolyte powders for thin film preparation

The development of uniform electrolyte thin films minimizes the ohmic loss of ceramic oxide electrolyzers and/or fuel cells, increasing their efficiency. In this work, thin films of BaZr_0.85Y_0.15O_3?δ (BZY) electrolyte have been obtained over a 40 vol% Nickel–BaZr_0.85Y_0.15O_3?δ (Ni–BZY) cermet anode support by spin coating. To facilitate this aim, stable suspensions have been tailored, by methodically determining suitable solvents and additives (surfactants and/or thickeners). Sedimentation studies showed that ethanol and 1-methoxy-2-propanol can produce similar, stable 5% w/w BZY suspensions. The best result was obtained by simultaneously adding 1.5 wt% of ZEPHRYM PD 7000 (a commercial polyoxyalkylene amine derivative surfactant) and 0.3 wt% of polyvinyl butyral (PVB) in 1-methoxy-2-propanol. Suspensions of 1-methoxy-2-propanol with higher powder concentration (25% w/w) also show good stability that was improved by the addition of 1 wt% of ZEPHRYM. Using this system, dense BZY films of around 14 μm thick could be successfully obtained at 1500 °C.     

Thermal and mechanical properties of LaNbO4-based ceramics

Thermal and mechanical properties of polycrystalline La_1−xA_xNbO₄ (x = 0, 0.005, 0.02 and A = Ca, Sr and Ba) are reported. The materials possess a ferroelastic to paraelastic phase transition close to 500 °C, and the linear thermal expansion is significantly lower (8.6 ± 0.5 × 10⁻⁶ °C⁻¹) for the paraelastic phase compared to the ferroelastic phase (15 ± 3 × 10⁻⁶ °C⁻¹). The hardness was significantly higher for acceptor doped materials (6 GPa) compared to pure LaNbO₄ (3 GPa) due to a significantly smaller average grain size. The fracture toughness of La_0.98Sr_0.02NbO₄, measured by single edge V-notched beam method, was 1.7 ± 0.2 MPa m^1/2 independent of temperature up to 600 °C. The ferroelastic properties of the materials were confirmed by non-linear relationships between stress and strain during compression/decompression, a remnant strain after decompression and the presence of ferroelastic domains. The mechanical properties of LaNbO₄-based materials are discussed with focus on ferroelasticity, microcracking due to crystallographic anisotropy and pinning of ferroelastic domain boundaries.     

Inoculation of beef with low concentrations of Escherichia coli O157:H7 and examination of factors that interfere with its detection by culture isolation and rapid methods

Currently used industry testing programs require the ability to detect Escherichia coli O157:H7 in samples of beef trim or ground beef at levels as low as 1 CFU/375 g. We present a reliable protocol for generating a control inoculum for verification testing at this low concentration and evaluate its use. Results show that half of all samples received no cells when 1 CFU was the target concentration and that targets greater than 3 CFU were much more reliable. Detection by culture isolation and two commercial assays, Qualicon BAX-MP and BioControl GDS, detected 94% ± 11%, 92% ± 10%, and 92% ± 7% of samples inoculated with 5.4 CFU (range 1 to 9 CFU), respectively. We also examined the effect of background aerobic plate count (APC) bacteria and fat content effects on the detection of E. coli O157:H7. At APC concentrations below 6 log CFU/g, the rapid methods detected all beef trim samples inoculated with 26 CFU of E. coli O157:H7 per 65 g. At an APC of 6.7 log CFU/g, culture, BAX-MP, and GDS detected 100, 75, and 13%, respectively, of inoculated samples. Neither commercial method detected E. coli O157:H7 in the samples when APC was 7.7 log CFU/g, whereas culture was able to detect 63% of E. coli O157:H7 in the samples when APC was at this concentration. Increased fat content correlated with decreasing recovery of immunomagnetic separation beads, but this was not observed to interfere with detection of E. coli O157:H7.     

A test of behavioral family therapy to augment exposure for combat-related posttraumatic stress disorder.

This study tested a family-based skills-building intervention in veterans with chronic combat-related posttraumatic stress disorder (PTSD). Veterans and a family member were randomly assigned to 1 of 3 conditions: (a) waiting list, (b) 18 sessions of twice-weekly exposure therapy, or (c) 18 sessions of twice-weekly exposure therapy followed by 16 sessions of behavioral family therapy (BFT). Participation in exposure therapy reduced PTSD positive symptoms (e.g., reexperiencing and hyperarousal) but not PTSD negative symptoms. Positive symptom gains were maintained at 6-month follow-up. However, participation in BFT had no additional impact on PTSD symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)