Shape computations without compositions

Parametric CAD supports design explorations through generative methods which compose and transform geometric elements. This paper argues that elementary shape computations do not always correspond to valid compositional shape structures. In many design cases generative rules correspond to compositional structures, but for relatively simple shapes and rules it is not always possible to assign a corresponding compositional structure of parts which account for all operations of the computation. This problem is brought into strong relief when design processes generate multiple compositions according to purpose, such as product structure, assembly, manufacture, etc. Is it possible to specify shape computations which generate just these compositions of parts or are there additional emergent shapes and features? In parallel, combining two compositions would require the associated combined computations to yield a valid composition. Simple examples are presented which throw light on the issues in integrating different product descriptions (i.e. compositions) within parametric CAD

Symptom profiles of psychiatric disorders based on graded disease classes: an illustration using data from the WHO International Pilot Study of Schizophrenia

The Grade of Membership (GoM) model is a classification procedure which allows a person to be a member of more than one diagnostic class. It simultaneously quantifies the degrees of membership in classes while generating the discrete symptom profiles or ‘pure types' describing classes. The model was applied to the symptomatology, history, and follow-up of 1065 cases in the WHO International Pilot Study of Schizophrenia. The model produced an eight diagnostic class or ‘pure type' solution, of which five were related to the diagnostic concepts of schizophrenia and paranoid disorder, two types were affective disorders, and one asymptomatic type. A subtype of paranoid schizophreniform disorder found primarily in developing countries was identified. There was a strong association between pure types and the original clinical and computer generated (CATEGO) diagnoses. A GoM based psychiatric classification might more clearly identify core disease processes than conventional classification models by filtering the confounding effects of individual heterogeneity from pure type definition

How the asymmetry of internal potential influences the shape of I-V characteristic of nanochannels

Ion transport in biological and synthetic nanochannels is characterized by such phenomena as ion current fluctuations, rectification, and pumping. Recently, it has been shown that the nanofabricated synthetic pores could be considered as analogous to biological channels with respect to their transport characteristics \cite{Apel, Siwy}. The ion current rectification is analyzed. Ion transport through cylindrical nanopores is described by the Smoluchowski equation. The model is considering the symmetric nanopore with asymmetric charge distribution. In this model, the current rectification in asymmetrically charged nanochannels shows a diode-like shape of $I-V$ characteristic. It is shown that this feature may be induced by the coupling between the degree of asymmetry and the depth of internal electric potential well. The role of concentration gradient is discussed

Simulation of associative learning with the replaced elements model

Associative learning theories can be categorised according to whether they treat the representation of stimulus compounds in an elemental or configural manner. Since it is clear that a simple elemental approach to stimulus representation is inadequate there have been several attempts to produce more elaborate elemental models. One recent approach, the Replaced Elements Model (Wagner, 2003), reproduces many results that have until recently been uniquely predicted by Pearce’s Configural Theory (Pearce, 1994). Although it is possible to simulate the Replaced Elements Model using “standard” simulation programs the generation of the correct stimulus representation is complex. The current paper describes a method for simulation of the Replaced Elements Model and presents the results of two example simulations that show differential predictions of Replaced Elements and Pearce’s Configural Theor

Basic principles of postgrowth annealing of CdTe:Cl ingot to obtain semi-insulating crystals

The process of annealing of a CdTe:Cl ingot during its cooling after growth was studied. The annealing was performed in two stages: a high-temperature stage, with an approximate equality of chlorine and cadmium vacancy concentrations established at the thermodynamic equilibrium between the crystal and vapors of volatile components, and a low-temperature stage, with charged defects interacting to form neutral associations. The chlorine concentrations necessary to obtain semi-insulating crystals were determined for various ingot cooling rates in the high temperature stage. The dependence of the chlorine concentration [Cl+Te] in the ingot on the temperature of annealing in the high-temperature stage was found. The carrier lifetimes and drift mobilities were obtained in relation to the temperature and cadmium vapor pressure in the postgrowth annealing of the ingot.Comment: 6 pages, 6 figure

Electromagnetic Induction Sensor Data to Identify Areas of Manure Accumulation on a Feedlot Surface

A study was initiated to test the validity of using electromagnetic induction (EMI) survey data, a prediction-based sampling strategy, and ordinary linear regression modeling to predict spatially variable feedlot surface manure accumulation. A 30- by 60-m feedlot pen with a central mound was selected for this study. A Dualem-1S EMI meter (Dualem Inc., Milton, ON, Canada) pulled on 2-m spacing was used to collect feedlot surface apparent electrical conductivity (ECa) data. Meter data were combined with global positioning system coordinates at a rate of fi ve readings per second. Two 20-site sampling approaches were used to determine the validity of using EMI data for prediction-based sampling. Soil samples were analyzed for volatile solids (VS), total N (TN), total P (TP), and Cl−. A stratified random sampling (SRS) approach (n = 20) was used as an independent set to test models estimated from the prediction-based (n = 20) response surface sample design (RSSD). Th e RSSD sampling plan demonstrated better design optimality criteria than the SRS approach. Excellent correlations between the EMI data and the ln(Cl−), TN, TP, and VS soil properties suggest that it can be used to map spatially variable manure accumulations. Each model was capable of explaining \u3e90% of the constituent sample variations. Fitted models were used to estimate average manure accumulation and predict spatial variations. The corresponding prediction maps show a pronounced pen design effect on manure accumulation. This technique enables researchers to develop precision practices to mitigate environmental contamination from beef feedlots