Fitting polynomial surfaces to triangular meshes with Voronoi squared distance minimization

This paper introduces Voronoi squared distance minimization (VSDM), an algorithm that fits a surface to an input mesh. VSDM minimizes an objective function that corresponds to a Voronoi-based approximation of the overall squared distance function between the surface and the input mesh (SDM). This objective function is a generalization of the one minimized by centroidal Voronoi tessellation, and can be minimized by a quasi-Newton solver. VSDM naturally adapts the orientation of the mesh elements to best approximate the input, without estimating any differential quantities. Therefore, it can be applied to triangle soups or surfaces with degenerate triangles, topological noise and sharp features. Applications of fitting quad meshes and polynomial surfaces to input triangular meshes are demonstrated.     

Tissue variation in hydrocarbon composition in the rabbit

This study, which deals with the distribution of hydrocarbons in seven types of rabbit tissues, was done for the purpose of providing information that might help shed light on the biological relevance of the hydrocarbons in mammalian metabolism. Liver, kidneys, brain, spleen, skeletal muscle, perinephric adipose, and a sample of blood serum were collected from a single animal for analysis of their hydrocarbon composition. The analytical methodology consisted of solvent extraction, saponification (adipose), elution chromatography on hydrated alumina, and combined gas chromatography-mass spectrometry. Hydrocarbons were detected in all of the tissues examined at concentrations estimated to range from 0.1 to 0.01% of the total lipid extracted. Three quite distinct distribution modes were recognized. The bulk of the identified components consisted of normal, saturated, nonterpenoid hydrocarbons in the C₁₆ to C₃₃ range. Squalene, phytene, phytadiene, and pristane were the only terpenoids detected. Nonterepenoid branched (iso andanteiso) hydrocarbons were identified unequivocally and in significant amounts in the muscle only. The adipose was the only tissue which was relatively rich in monoalkenes, and its overall hydrocarbon composition closely resembled that of the feed. The results of the study are not consistent with metabolic inertness. The observed qualitative and quantitative differences might reflect function and metabolic activities of the individual organs in a way yet to be elucidated. Presented in part at the AOCS Spring Meeting, New Orleans, April, 1976.     

Fractal characterization of the fissures occuring during polymerization of low-profile unsaturated polyester resins

Blends of unsaturated polyester resin and polyvinylacetate (PVAc) were cured between two glass slides. In this case, the low-profile effect arises by fissuring with a fractal geometry. This paper shows how the fractal dimension of the fissures depends on the PVAc amount and on the cure temperature. These results are discussed with the present knowledge about the polyester network morphology in two phases more or less co-continuous.     

The fatty acid composition of purified fractions of cold-pressed peanut oil

Cold-pressed peanut oil was separated into chromatographically homogeneous fractions by column chromatography. The fatty acid composition of the major fractions was determined by gas chromatography. The phosphatides, and especially the cephalins, had a higher palmitate content than did the triglycerides. Palmitate was the dominant fatty acid in the phosphatidyl-serines.     

MPaaS: Mobility prediction as a service in telecom cloud

Mobile applications and services relying on mobility prediction have recently spurred lots of interest. In this paper, we propose mobility prediction based on cellular traces as an infrastructural level service of telecom cloud. Mobility Prediction as a Service (MPaaS) embeds mobility mining and forecasting algorithms into a cloud-based user location tracking framework. By empowering MPaaS, the hosted 3rd-party and value-added services can benefit from online mobility prediction. Particularly we took Mobility-aware Personalization and Predictive Resource Allocation as key features to elaborate how MPaaS drives new fashion of mobile cloud applications. Due to the randomness of human mobility patterns, mobility predicting remains a very challenging task in MPaaS research. Our preliminary study observed collective behavioral patterns (CBP) in mobility of crowds, and proposed a CBP-based mobility predictor. MPaaS system equips a hybrid predictor fusing both CBP-based scheme and Markov-based predictor to provide telecom cloud with large-scale mobility prediction capacity.     

Contribution of the C-terminal amino acid to the stability of Bacillus subtilis neutral protease

The role of the C-terminal Leu300 in maintaining thermal stabilityof the neutral protease of Bacillus subtilis was investigated.From model building studies based on the three dimensional structureof thermolysin, the neutral protease of B.thermoproteolyticus,it was conduded that this residue is located in a hydrophobicpocket composed of residues located in the C-terminal and themiddle domain. To test the hypothesis that Leu300, by contributingto a stabilizing interaction between these domains, is importantfor enzyme stability, several neutral protease mutants wereconstructed and characterized. The thermostability of the enzymewas lowered by deleting Leu300 or by replacing this residueby a smaller (Ala), a polar (Asn) or a sterically unfavourable(He) amino acid. Thermostabiity was increased upon replacingLeu300 by Phe. These results are in agreement with model-buildingstudies. The effects on thermostability observed after mutatingthe corresponding Val318 in the thermostable neutral proteaseof B.stearothermophilus were less pronounced.     

Which symbol grounding problem should we try to solve?

Floridi and Taddeo propose a condition of ‘zero semantic commitment’ for solutions to the grounding problem, and a solution to it. I argue briefly that their condition cannot be fulfilled, not even by their own solution. After a look at Luc Steel's very different competing suggestion, I suggest that we need to re-think what the problem is and what role the ‘goals’ in a system play in formulating the problem. On the basis of a proper (syntactic) understanding of computing, I come to the conclusion that the only sensible grounding problem is how we can explain and re-produce the behavioural ability and function of meaning in artificial computational agents.     

Scheduling evacuation operations

In this paper, we consider a large-scale evacuation problem after a major disaster. The evacuation is assumed to occur by means of a fleet of buses, thus leading to scheduling the evacuation operations by buses [(bus evacuation problem (BEP)]. We propose time-indexed formulations as well as heuristic algorithms such as greedy algorithms and a matheuristic. This matheuristic uses the former formulation to improve the best solution obtained by the greedy heuristics. In computational experiments, we analyze and evaluate the efficiency of the proposed solution algorithms.     

Assessment of crowdsourcing and gamification loss in user-assisted object segmentation

There has been a growing interest in applying human computation – particularly crowdsourcing techniques – to assist in the solution of multimedia, image processing, and computer vision problems which are still too difficult to solve using fully automatic algorithms, and yet relatively easy for humans. In this paper we focus on a specific problem – object segmentation within color images – and compare different solutions which combine color image segmentation algorithms with human efforts, either in the form of an explicit interactive segmentation task or through an implicit collection of valuable human traces with a game. We use Click’n’Cut, a friendly, web-based, interactive segmentation tool that allows segmentation tasks to be assigned to many users, and Ask’nSeek, a game with a purpose designed for object detection and segmentation. The two main contributions of this paper are: (i) We use the results of Click’n’Cut campaigns with different groups of users to examine and quantify the crowdsourcing loss incurred when an interactive segmentation task is assigned to paid crowd-workers, comparing their results to the ones obtained when computer vision experts are asked to perform the same tasks. (ii) Since interactive segmentation tasks are inherently tedious and prone to fatigue, we compare the quality of the results obtained with Click’n’Cut with the ones obtained using a (fun, interactive, and potentially less tedious) game designed for the same purpose. We call this contribution the assessment of the gamification loss, since it refers to how much quality of segmentation results may be lost when we switch to a game-based approach to the same task. We demonstrate that the crowdsourcing loss is significant when using all the data points from workers, but decreases substantially (and becomes comparable to the quality of expert users performing similar tasks) after performing a modest amount of data analysis and filtering out of users whose data are clearly not useful. We also show that – on the other hand – the gamification loss is significantly more severe: the quality of the results drops roughly by half when switching from a focused (yet tedious) task to a more fun and relaxed game environment.