Analysis of consumer preferences expressed by prioritization chains

In this paper, a novel approach is proposed to analyze and interpret consumer preference data expressed as weak orderings (ie, preference chains) over a set of alternatives. A simple distance metric based on cosine similarity is used to assess the repeatability and reproducibility of consumer preferences. These concepts have been borrowed from metrology and can be usefully adopted to evaluate the meaningfulness of aggregated measures (eg, median preference chain) defined over the preference data set. The proposed approach is fully exploited through a real case study involving a group of consumers expressing their preferences over alternative types of pizza toppings.     

Utilitarian Desires

Autonomous agents reason frequently about preferences such as desires and goals. In this paper we propose a logic of desires with a utilitarian semantics, in which we study nonmonotonic reasoning about desires and preferences based on the idea that desires can be understood in terms of utility losses (penalties for violations) and utility gains (rewards for fulfillments). Our logic allows for a systematic study and classification of desires, for example by distinguishing subtly different ways to add up these utility losses and gains. We propose an explicit construction of the agent's preference relation from a set of desires together with different kinds of knowledge. A set of desires extended with knowledge induces a set of distinguished utility functions by adding up the utility losses and gains of the individual desires, and these distinguished utility functions induce the preference relation.     

On Independence of Variants of the Weak Pigeonhole Principle

The principle states that no oracle circuit can compute a surjection of a onto b. We showthat is independent of for various choices of the parameters, , , P. We also improve the known separation of iWPHP(PV) from under cryptographic assumptions.     

Development and applications of a software tool for diarthrodial joint analysis

This paper describes a new software environment for advanced analysis of diarthrodial joints. The new tool provides a number of elaboration functions to investigate the joint kinematics, bone anatomy, and ligament and tendon properties. In particular, the shapes and the contact points of the articulating surfaces can be displayed and analysed through 2D user-defined sections and fittings (lines or conics). Ligament behaviour can be evaluated during joint movement, through the computation of elongations, orientations, and fiber strain. Motion trajectories can be also analysed through the calculation of helical axes, instantaneous rotations, and displacements in specific user-chosen coordinate reference frames. The software has an user-friendly graphical interface to display four-dimensional data (time-space data) obtained from medical images, navigation systems, spatial linkages or digitalizers, and can also generate printable reports and multiple graphs as well as ASCII files that can be imported to spreadsheet programs such as Microsoft Excel.     

MoDALAS: addressing assurance for learning-enabled autonomous systems in the face of uncertainty

Software and Systems Modeling - Increasingly, safety-critical systems include artificial intelligence and machine learning components (i.e., learning-enabled components (LECs)). However, when...     

Spontaneous Generation of Magnetic Flux in Superconductors: Testing the Model

The Kibble-Zurek scenario of the generation of topological defects, applied to superconductors, predicts the spontaneous formation of magnetic flux during a rapid quench through T^c. The predicted amount of net flux scales as the 1/8 power of the cooling rate, and as the square root of the circumference of the sample. Our experimental data is broadly consistent with the first prediction, while the second one is yet to be tested. We describe a proposed experiment to test this prediction. In addition, we describe additional observations of spontaneous flux generated through a different mechanism. PACS numbers: 05.70.Ln, 74.40.+k, 11.27.+d.     

Biomechanical measurements of axial crush injury to the distal condyles of human and synthetic femurs

Few studies have evaluated the 'bulk' mechanical properties of human longbones and even fewer have compared human tissue to the synthetic longbones increasingly being used by researchers. Distal femur fractures, for example, comprise about 6% of all femur fractures, but the mechanical properties of the distal condyles of intact human and synthetic femurs have not been well quantified in the literature. To this end, the distal portions of a series of 16 human fresh-frozen femurs and six synthetic femurs were prepared identically for mechanical testing. Using a flat metal plate, an axial 'crush' force was applied in-line with the long axis of the femurs. The two femur groups were statistically compared and values correlated to age, size, and bone quality. Results yielded the following: crush stiffness (human, 1545 +/- 728 N/mm; synthetic, 3063 +/- 1243 N/mm; p = 0.002); crush strength (human, 10.3 +/- 3.1 kN; synthetic, 12.9 < or = 1.7 kN; p = 0.074); crush displacement (human, 6.1 +/- 1.8 mm; synthetic, 2.8 +/- 0.3 mm; p = 0.000); and crush energy (human, 34.8 +/- 15.9J; synthetic, 18.1 +/- 5.7J; p = 0.023). For the human femurs, there were poor correlations between mechanical properties versus age, size, and bone quality (R2 < or = 0.18), with the exception of crush strength versus bone mineral density (R2 = 0.33) and T-score (R2 = 0.25). Human femurs failed mostly by condyle 'roll back' buckling (15 of 16 cases) and/or unicondylar or bicondylar fracture (7 of 16 cases), while synthetic femurs all failed by wedging apart of the condyles resulting in either fully or partially displaced condylar fractures (6 of 6 cases). These findings have practical implications on the use of a flat plate load applicator to reproduce real-life clinical failure modes of human femurs and the appropriate use of synthetic femurs. To the authors' knowledge, this is the first study to have done such an assessment on human and synthetic femurs.     

Profile-based 3D-aided face recognition

This paper presents a framework for automatic face recognition based on a silhouetted face profile (URxD-PV). Previous research has demonstrated the high discriminative potential of this biometric. Compared to traditional approaches in profile-based recognition, our approach is not limited to only standard side-view faces. We propose to explore the feature space of profiles under various rotations with the aid of a 3D face model. In the enrollment mode, 3D data of subjects are acquired and used to create profiles under different rotations. The features extracted from these profiles are used to train a classifier. In the identification mode, the profile is extracted from the side-view image and its metadata is matched with the gallery metadata. We validate the accuracy of URxD-PV using data from publicly available databases.     

Soft object deformation monitoring and learning for model-based robotic hand manipulation

This paper discusses the design and implementation of a framework that automatically extracts and monitors the shape deformations of soft objects from a video sequence and maps them with force measurements with the goal of providing the necessary information to the controller of a robotic hand to ensure safe model-based deformable object manipulation. Measurements corresponding to the interaction force at the level of the fingertips and to the position of the fingertips of a three-finger robotic hand are associated with the contours of a deformed object tracked in a series of images using neural-network approaches. The resulting model captures the behavior of the object and is able to predict its behavior for previously unseen interactions without any assumption on the object's material. The availability of such models can contribute to the improvement of a robotic hand controller, therefore allowing more accurate and stable grasp while providing more elaborate manipulation capabilities for deformable objects. Experiments performed for different objects, made of various materials, reveal that the method accurately captures and predicts the object's shape deformation while the object is submitted to external forces applied by the robot fingers. The proposed method is also fast and insensitive to severe contour deformations, as well as to smooth changes in lighting, contrast, and background.     

Thermoresponsive Molecular Brushes with a Rigid-Chain Aromatic Polyester Backbone and Poly-2-alkyl-2-oxazoline Side Chains

A new polycondensation aromatic rigid-chain polyester macroinitiator was synthesized and used to graft linear poly-2-ethyl-2-oxazoline as well as poly-2-isopropyl-2-oxazoline by cationic polymerization. The prepared copolymers and the macroinitiator were characterized by NMR, GPC, AFM, turbidimetry, static, and dynamic light scattering. The molar masses of the polyester main chain and the grafted copolymers with poly-2-ethyl-2-oxazoline and poly-2-isopropyl-2-oxazoline side chains were 26,500, 208,000, and 67,900, respectively. The molar masses of the side chains of poly-2-ethyl-2-oxazoline and poly-2-isopropyl-2-oxazoline and their grafting densities were 7400 and 3400 and 0.53 and 0.27, respectively. In chloroform, the copolymers conformation can be considered as a cylinder wormlike chain, the diameter of which depends on the side chain length. In water at low temperatures, the macromolecules of the poly-2-ethyl-2-oxazoline copolymer assume a wormlike conformation because their backbones are well shielded by side chains, whereas the copolymer with short side chains and low grafting density strongly aggregates, which was visualized by AFM. The phase separation temperatures of the copolymers were lower than those of linear analogs of the side chains and decreased with the concentration for both samples. The LCST were estimated to be around 45 °C for the poly-2-ethyl-2-oxazoline graft copolymer, and below 20 °C for the poly-2-isopropyl-2-oxazoline graft copolymer.