Position synchronization of multiple motion axes with adaptive coupling control

A new control approach to position synchronization of multiple motion axes is developed, by incorporating cross-coupling technology into adaptive control architecture. The control strategy is to stabilize position tracking of each axis while synchronizing its motion with other axes’ motions so that differential position errors amongst axes converge to zero. The proposed adaptive controller and parameter estimator employ coupling control by feeding back position errors and differential position errors, and have been realized to guarantee asymptotic convergence to zero of both position and synchronization errors. Simulations conducted on a multi-axis motion control system demonstrate the effectiveness of the method.     

Healing the psyche through music, myth, and ritual.

According to Carl Jung, a person's symptoms occur as a result of the psyche's creative attempt to self-regulate. These symptoms are viewed as the symbol-making function of the psyche. Music therapy as a therapeutic tool is also viewed as having a symbol-making function in that the physical act of making music involves conceptualizing one's symptoms into sounds. The sound serves as a musical symbol of the symptom. The myth of Orpheus is offered as an example of how early man amplified the creative potential contained in music to heal from life's woes. The Orphic archetype illustrates that music serves as a medium for healing and as an expression of Self. That psyche can be healed by music is a reminder of the connection between music therapy and the myth of Orpheus. In using the therapeutic tool of music one can transcend, through the symbol making process inherent in music therapy, the tension of opposites that are created at the crossroads of disease and wellness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Efficient Spreadsheet Algorithm for First-Order Reliability Method

A new spreadsheet-cell-object-oriented algorithm for the first-order reliability method is proposed and illustrated for cases with correlated nonnormals and explicit and implicit performance functions. The new approach differs from the writers earlier algorithm by obviating the need for computations of equivalent normal means and equivalent normal standard deviations. It obtains the solution faster and is more efficient, robust, and succinct. Other advantages include ease of initialization prior to constrained optimization, ease of randomization of initial values for checking robustness, and fewer required optimization constraints during spreadsheet-automated search for the design point. Two cases with implicit performance functions, namely an asymmetrically loaded beam on Winkler medium and a strut with complex supports are analyzed using the new approach and discussed. Comparisons are also made between the proposed approach and that based on Rosenblatt transformation.     

Emergency department status boards: user-evolved artefacts for inter- and intra-group coordination

Large, easily viewed status boards are commonly used in some healthcare settings such as emergency departments, operating theaters, intensive care units, and inpatient wards. Because these artefacts were developed by front-line users, and have little to no supervisory or regulatory control, they offer valuable insights into the theories of work and hazard held by those users. Although the status boards case were locally developed over many years for within-group coordination, they have also become useful for between-group coordination across organizational boundaries. In this paper, we compare and contrast the use of such status boards in two disparate settings: a US emergency department, and a UK pediatric ward, and note striking similarities in their form and usage, despite the large differences in setting.     

Nonlinear model predictive control with polytopic invariant sets

Ellipsoidal invariant sets have been widely used as target sets in model predictive control (MPC). These sets can be computed by constructing appropriate linear difference inclusions together with additional constraints to ensure that the ellipsoid lies within a given inclusion polytope. The choice of inclusion polytope has a significant effect on the size of the target ellipsoid, but the optimal inclusion polytope cannot in general be computed systematically. This paper shows that use of polytopic invariant sets overcomes this difficulty, allowing larger stabilizable sets without loss of performance. In the interests of online efficiency, consideration is focused on interpolation-based MPC.     

Frequency domain solution to delay-type Nehari problem

This paper generalizes the frequency-domain results on the delay-type Nehari problem in the stable case to the unstable case. The solvability condition of the delay-type Nehari problem is formulated in terms of the nonsingularity of three matrices. The optimal value γ_opt is the maximal γ∈(0,∞) such that one of the three matrices becomes singular. All sub-optimal compensators are parameterized in a transparent structure incorporating a modified Smith predictor.     

EM procedures using mean field-like approximations for Markov model-based image segmentation

Image segmentation using Markov random fields involves parameter estimation in hidden Markov models for which the EM algorithm is widely used. In practice, difficulties arise due to the dependence structure in the models and approximations are required. Using ideas from the mean field approximation principle, we propose a class of EM-like algorithms in which the computation reduces to dealing with systems of independent variables. Within this class, the simulated field algorithm is a new stochastic algorithm which appears to be the most promising for its good performance and speed, on synthetic and real image experiments.     

Determination of vitality from a non-invasive biomedical measurement for use in fingerprint scanners

Fingerprints are the oldest and most widely used biometrics for personal identification. Unfortunately, it is usually possible to deceive automatic fingerprint identification systems by presenting a well-duplicated synthetic or dismembered finger. This paper introduces one method to provide fingerprint vitality authentication in order to solve this problem. Detection of a perspiration pattern over the fingertip skin identifies the vitality of a fingerprint. Mapping the two-dimensional fingerprint images into one-dimensional signals, two ensembles of measures, namely static and dynamic measures, are derived for classification. Static patterns as well as temporal changes in dielectric mosaic structure of the skin, caused by perspiration, demonstrate themselves in these signals. Using these measures, this algorithm quantifies the sweating pattern and makes a final decision about vitality of the fingerprint by a neural network trained by examples.     

Computer support for strategic organizational decision-making

While information systems continue to be promoted within organizations as tools to support strategic decision-making, there is growing concern over the ability of such systems to model the social and political complexity of the situations to which they are being applied. This paper examines the nature of organizational decision-making and the use of computer-based systems to support this activity. The debate queries the extent to which such artifacts should be allowed to become enmeshed and embedded within the strategic decision-making activities of organizations which operate within increasingly complex environments.