Effects of Magnetic Field on Conductance and Electroluminescence in Organic Devices

In this contribution we review recent advances of the organic magnetic field effects, namely magneto-conductance and magneto-electroluminescence, in both experiment and theory. We describe a number of processes, including the polaron-pair and triplet-triplet pair mechanisms that are responsible for the magnetic field effects in organic semiconductor systems. For the polaron pair mechanism, we review in detail the effect of the hyperfine interaction, both isotropic and anisotropic; different g-factors of the two polarons composing the pair; and the spin orbit interaction. The effect of the triplet-triplet annihilation process is also analyzed. Experimental examples for each case treated theoretically are given.     

Collapse Analysis,Defect Sensitivity and Load Paths in Stiffened Shell Composite Structures

An experimental program for collapse of curved stiffened composite shell structures encountered a wide range of initial and deep buckling mode shapes. This paper presents work to determine the significance of the buckling deformations for determining the final collapse loads and to understand the source of the variation. A finite element analysis is applied to predict growth of damage that causes the disbonding of stiffeners and defines a load displacement curve to final collapse. The variability in material properties and geometry is then investigated to identify a range of buckling modes and development of deep postbuckling deformation encountered in the experimental program. Finally the load paths for the damaged panels are used to visualise the load transfer and enhance the physical understanding of the load displacement history.     

Attachment and anger in an anxiety-provoking situation.

In this study, women were told they would engage in an anxiety-provoking activity. Women then waited with their dating partner for the activity to begin. During this 5-min "stress" period, each couple's interaction was videotaped unobtrusively. Each couple was then told that the woman would not have to do the stressful activity, and each couple was unobtrusively videotaped again during a 5-min "recovery" period. The behavior of both partners was then coded during both periods. The major results revealed that more-avoidant men displayed greater anger during the stress period, especially if their partners were more anxious or distressed or sought more support from them. More-avoidant women also displayed greater anger, particularly if they were highly anxious or distressed and received little support or encountered anger from their partners. During the recovery period, highly ambivalent women behaved more negatively toward their partners if they had been more anxious in the stress period or had sought more support from their partners. These results are discussed in terms of attachment theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Performance of ad hoc networks with two-hop relay routing and limited packet lifetime (extended version)

We consider a mobile ad hoc network consisting of three types of nodes (source, destination and relay nodes) and using the two-hop relay routing. This type of routing takes advantage of the mobility and the storage capacity of the nodes, called the relay nodes, in order to route packets between a source and a destination. Packets at relay nodes are assumed to have a limited lifetime in the network. Nodes are moving inside a bounded region according to some random mobility model. Closed-form expressions and asymptotic results when the number of nodes is large are provided for the packet delivery delay and for the energy needed to transmit a packet from the source to its destination. We also introduce and evaluate a variant of the two-hop relay protocol that limits the number of generated copies in the network. Our model is validated through simulations for two mobility models (random waypoint and random direction mobility models), and the performance of the two-hop routing and of the epidemic routing protocols are compared.     

Regular Ordering and Applications in Control Policies

In this paper we introduce the notion of regular ordering for periodic sequences based on the gaps between the entries. We define the notion of regular preserving functions using Schur convexity. This is used to extend some optimization results in queuing control problems. In particular, we show that the maximal traveling time in a stochastic event graph as well as the transmission times in a channel with redundancy, decrease (in the stochastic sense) when the input sequence becomes more regular.     

Natural hierarchical refinement for finite element methods

Current formulations of adaptive finite element mesh refinement seem simple enough, but their implementations prove to be a formidable task. We offer an alternative point of departure which yields equivalent adapted approximation spaces wherever the traditional mesh refinement is applicable, but our method proves to be significantly simpler to implement. At the same time it is much more powerful in that it is general (no special tricks are required for different types of finite elements), and applicable for some newer approximations where traditional mesh refinement concepts are not of much help, for instance on subdivision surfaces. Copyright © 2003 John Wiley & Sons, Ltd.     

Detection measures in real-life criminal guilty knowledge tests.

Provides a 1st attempt to compare the validity of the respiration line length (RLL) and skin resistance response (SRR) amplitude in real-life criminal guilty knowledge tests (GKTs). GKT records of 40 innocent and 40 guilty Ss, for whom actual truth was established by confession, were assessed for their accuracy. When a predefined decision rule was used and inconclusive decisions were excluded, 97.4% of the innocent Ss and 53.3% of the guilty Ss were correctly classified with the SRR measure. For the RLL measure, the respective results were 97.2% and 53.1%. The combination of both measures improved detection of guilty Ss to 75.8% and decreased detection of innocent Ss to 94.1%. The combined measure seems to be a more useful means of identifying guilty suspects than each physiological measure alone. The results elaborate and extend those obtained in a previous field study (E. Elaad, 1990). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Machine identification of buds in images of plant shoots

Tissue cultures find increasingly widespread applications for cloning of many plants. Commercial propagation by tissue cultures is limited to ornamental plants, because the cost of skilled labor required cannot compete with conventional propagation methods. To cut down the cost, some automation is essential. A cost-effective approach is to chop the plantlets into segments on a conveying production line while using machine vision for identifying and locating the number and positions of propagation organs in images of the plantlet segments. Plantlet segments without propagation organs will be rejected, while segments with viable buds will be selected for subculturing. To this end, a machine-vision-controlled automatic subculturing system for potato tissue cultures is proposed as a simpler and more cost-effective solution than the popular trend of imitating the manual sub-culturing task by a robot. A simple and relatively fast image-processing algorithm particularly suitable for classification of potato tissue cultures, was developed. In lieu of the general Medial Axis Transform approach, this specialized algorithm takes advantage of the inherent difference between the geometrical shape and gray scale levels of the stems and the leaves as well as of the rather simple connectivity rules of attachment between them. The results indicate that machine inspection and classification of tissue culture plantlets is possible, but considerably more work needs to be done before this technique is fully developed for automating tissue culture processes.     

Detection of guilty knowledge in real-life criminal investigations.

The present study provides a first attempt to estimate the validity of the Guilty Knowledge Test (GKT) in real-life criminal investigations. Skin resistance responses in GKT records of 50 innocent and 48 guilty Ss, for whom actual truth was established by confession, were analyzed by two methods. On the basis of an a priori decision rule, 98% of the innocent and 42% of the guilty Ss were correctly classified. Signal detection measures based on various possible decision rules indicated that the distribution of guilty Ss was highly differentiated from the distribution of innocent Ss. An optimal decision rule yielded correct classifications for 94% of the innocent Ss and 65% of the guilty Ss. These results suggest that the GKT could be a useful investigative tool that protects innocent suspects from being falsely classified as guilty. The false-negative identifications were accounted for in terms of the realistic conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)