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A fiber-optic two-color pyrometer with high spatial and temporal resolution has been applied to measure temperatures at an external turning process. Different measurement positions have been realized at the chip and the workpiece. The measurements have been performed at three different workpiece materials: carbon steel AISI 1045, aluminum alloy AA 7075, and titanium alloy Ti6Al4V. The influences of different parameters like cutting speed, feed, and position of the measurement spot on the temperatures have been investigated. The cutting speed has been increased from conventional values up to 100 m/s for AISI 1045, 117 m/s for AA 7075, and 10 m/s for Ti6Al4E Additionally, a review of radiation thermometry techniques and applications regarding time resolved temperature measurements in metal cutting will be presented. [DOI: 10.1115/1.1763188]

Byline: Matthias Maschke (3), Johannes Weber (1), Albena Dimitrova (3), Udo Bonnet (2), Julia Bohrenkamper (3), Sonja Sturm (3), Kerstin Kindsvater (1), Bernhard W. Muller (2), Markus Gastpar (2), Hans-Christoph Diener (3), Michael Forsting (1), Dagmar Timmann (3) Keywords: cerebellum; brain iron concentration; FLASH sequence; interrater reliability Abstract: Abstract. The aim of the present study was to investigate age-related changes in iron-deposition in dentate nuclei using iron-induced susceptibility effects in magnetic resonance imaging. MR images from 74 healthy subjects (age range 20--68 years) were obtained using a three-dimensional (3D) T1-weighted fast low angle shot (FLASH) echo sequence. Signal intensities of the dentate nuclei and cerebellar white matter were bilaterally measured independently by three blinded investigators. The signal intensities of dentate nuclei were intraindividually normalised to the corresponding signal intensities of the cerebellar white matter of corresponding slices. Mean normalised signal intensities were correlated with age and compared between different age decades and gender. Intraclass correlation coefficients were high (dentate nuclei: 0.98, cerebellar white matter: 0.75) indicating sufficient interrater reliabilities for the determination of signal intensities. Bland-Altman analysis confirmed this finding. The normalised mean signal intensity of the dentate nuclei correlated inversely with age (r = --0.462, p &lt 0.0001). Comparison of age decades revealed that significant decreases took place between the third and fourth decade and to a lesser degree between the fourth and fifth decade. Moreover, variability of normalised mean signal intensities of the dentate nuclei increased significantly with age (r = 0.964, p = 0.008). There were no differences of the normalised mean signal intensities between genders. The present study revealed an agedependent decrease of signal intensities in dentate nuclei most likely reflecting an age-dependent increase in dentate iron concentration. These age-dependent changes have to be taken into account in interpretation of disease related MR changes of cerebellar nuclei in patients with degenerative or acquired cerebellar ataxia. Author Affiliation: (1) Department of Neuroradiology, University of Duisburg-Essen, Hufelandstr. 55, Essen, Essen, Germany (2) Department of Psychiatry and Psychotherapy, University of Duisburg-Essen, Virchowstr. 174, 45147, Essen, Germany (3) Department of Neurology, University of Duisburg-Essen, Hufelandstr. 55, 45122, Essen, Germany Article History: Registration Date: 01/01/2004 Received Date: 28/04/2003 Accepted Date: 30/01/2004

Research reveals that single-pass method is efficient for slender flows yielding accuracy comparable to the thin-layer Navier-Stokes solution. Data also suggest that for predominantly one directional flows, application of multiple-pass method improves the solution derived from single-phase method.

The method of artificial compressibility is used to solve the two-dimensional incompressible Navier Stokes equation including a low-Reynolds number two-layer kappa-tau turbulence model. The two layer model is applied to the fully turbulent channel flow which is calculated at two low Reynolds numbers. It is also applicable to the flow over a backward facing step calculated with two different channel configurations and at high Reynolds number.

The article presents a study which identifies disentangling structural brain alterations in gray matter volume (GM) linked with lifelong substance use disorders (SUDs) and violent behavior. The study made use of the psychopathy checklist-screening version to assess mental disorders, aggressive behavior, and psychopathy. The result of the study shows that the violent behavior was associated with a greater volume in the mesolimbic reward system.

Examines the novelty-elicited mismatch negativity (MMN) in patients with schizophrenia on admission and discharge from hospital. Analysis of the electrophysiological and clinical assessment of patients; Association of the improvements in symptom expression with MMN components.