The effects of liquid-CO2 cooling,MQL and cutting parameters on drilling performance

An investigation is made into the effects of liquid carbon dioxide (LCO₂) cooling, minimum-quantity lubrication (MQL) and cutting speed in drilling. Experimental measurements of torque, thrust force and temperature are made over a wide range of process and operating conditions. The resulting empirical models are used to quantify the individual contributions of the controlled parameters on drilling performance, and to facilitate temperature-based process optimization. Of particular interest is the need to carefully adjust the LCO₂ flow rate for any combination of MQL flow rate and cutting speed. The optimization is validated both in simulation and actual drilling tests.     

Modeling of nonlinear coil in a ferroresonant circuit

An adjustment of the standard method of converting measured RMS characteristics of the nonlinear coil into instantaneous characteristics has been suggested. A model of the nonlinear coil, obtained in this way, is used for predicting the prechaotic bifurcation points of a ferroresonant circuit. Slight improvements over the standard method are verified by the experimental results. The cause of the disagreement between the simulation and the measurement is identified.     

Image processing and machine learning for fully automated probabilistic evaluation of medical images

The paper presents results of our long-term study on using image processing and data mining methods in a medical imaging. Since evaluation of modern medical images is becoming increasingly complex, advanced analytical and decision support tools are involved in integration of partial diagnostic results. Such partial results, frequently obtained from tests with substantial imperfections, are integrated into ultimate diagnostic conclusion about the probability of disease for a given patient. We study various topics such as improving the predictive power of clinical tests by utilizing pre-test and post-test probabilities, texture representation, multi-resolution feature extraction, feature construction and data mining algorithms that significantly outperform medical practice. Our long-term study reveals three significant milestones. The first improvement was achieved by significantly increasing post-test diagnostic probabilities with respect to expert physicians. The second, even more significant improvement utilizes multi-resolution image parametrization. Machine learning methods in conjunction with the feature subset selection on these parameters significantly improve diagnostic performance. However, further feature construction with the principle component analysis on these features elevates results to an even higher accuracy level that represents the third milestone. With the proposed approach clinical results are significantly improved throughout the study. The most significant result of our study is improvement in the diagnostic power of the whole diagnostic process. Our compound approach aids, but does not replace, the physician's judgment and may assist in decisions on cost effectiveness of tests.     

On the Role of Curved Membrane Nanodomains and Passive and Active Skeleton Forces in the Determination of Cell Shape and Membrane Budding

Biological membranes are composed of isotropic and anisotropic curved nanodomains. Anisotropic membrane components, such as Bin/Amphiphysin/Rvs (BAR) superfamily protein domains, could trigger/facilitate the growth of membrane tubular protrusions, while isotropic curved nanodomains may induce undulated (necklace-like) membrane protrusions. We review the role of isotropic and anisotropic membrane nanodomains in stability of tubular and undulated membrane structures generated or stabilized by cyto- or membrane-skeleton. We also describe the theory of spontaneous self-assembly of isotropic curved membrane nanodomains and derive the critical concentration above which the spontaneous necklace-like membrane protrusion growth is favorable. We show that the actin cytoskeleton growth inside the vesicle or cell can change its equilibrium shape, induce higher degree of segregation of membrane nanodomains or even alter the average orientation angle of anisotropic nanodomains such as BAR domains. These effects may indicate whether the actin cytoskeleton role is only to stabilize membrane protrusions or to generate them by stretching the vesicle membrane. Furthermore, we demonstrate that by taking into account the in-plane orientational ordering of anisotropic membrane nanodomains, direct interactions between them and the extrinsic (deviatoric) curvature elasticity, it is possible to explain the experimentally observed stability of oblate (discocyte) shapes of red blood cells in a broad interval of cell reduced volume. Finally, we present results of numerical calculations and Monte-Carlo simulations which indicate that the active forces of membrane skeleton and cytoskeleton applied to plasma membrane may considerably influence cell shape and membrane budding.     

Environment-driven reachability for timed systems

International Journal on Software Tools for Technology Transfer - With an ever increasing complexity, the verification of critical embedded systems is a challenging and expensive task. Among the...     

Atomic layer deposition of Zn1−x Mg x O:Al transparent conducting films

Aluminum-doped zinc magnesium oxide (Zn_1?x Mg _x O:Al) films with the Mg content from x = 0 to 0.48 were obtained using atomic layer deposition (ALD). Together with the thorough studies of the properties of the deposited films, the ALD growth parameters conditioning possible applications of Zn_1?x Mg _x O:Al films as transparent electrodes are investigated. Very low film resistivities (≤~10^?3 Ω cm) and the metallic-type conductivity behavior at room temperature for Zn_1?x Mg _x O:Al films are observed for Mg content x < 0.19. The Mg content of x = 0.19 results in the optical absorption edge of Zn_1?x Mg _x O:Al films at 3.81 eV (325 nm). Other film parameters like work function or sheet resistance can be easily modified by variation of growth parameters.     

Application of Microscopic Simulation of Traffic Flows in Developing Evacuation Plans for Inhabitants

The paper presents the possibilities of implementing micro-simulation traffic tools in order to develop the evacuation plans. Well elaborated evacuation plans are the basis for alleviating the consequences resulting from emergencies. The simulation tools allow the design and verification of various evacuation planning scenarios with minimisation of costs and time. The paper provides detailed presentation of the basic characteristics of microscopic simulation of traffic flows, as well as examples of their implementation worldwide. The characteristics of the software tools are described through an overview of the basic settings ofPTV VISSIM （Planung Transport Verkehrin Stadten--Simulations model） program as one of the most significant representatives of these tools. The necessity of implementing the traffic tools in evacuation results from the crucial role of traffic in reducing the consequences of emergencies. These tools allow also a detailed analysis of the output data in order to select a suitable solution. The concluding part of the paper presents an example of evacuation of the population through the Jankomir node as part of the European project ＂preparedness for evacuation in case of a nuclear accident＂. The evacuation was performed through three scenarios in circumstances of higher or lower transport demand.     

Relationship between non‐alcoholic fatty liver disease and MIA syndrome

Non‐alcoholic fatty liver disease (NAFLD) is an important factor in the pathogenesis of cardiovascular diseases in the general population. Recently, it has been shown that NAFLD is highly prevalent in chronic kidney disease (CKD) patients. Ninety‐four hemodialysis (HD) patients were followed for a time period of 18 months or until death. Patient's survival rate was determined in relation to their nutritional and inflammatory state, and the presence of NAFLD. We also investigated the association between the presence of NAFLD and the patients' nutritional and inflammatory state. We did not find any significant association between the clinical parameters of nutritional status and the mortality rate. However, the mortality rate was statistically significantly higher in patients with low serum albumin and high high‐sensitive C‐reactive protein (hs‐CRP) levels and in those who had NAFLD. Surprisingly, patients who had received enteral nutrition did not have a better survival rate. The severity of liver steatosis was negatively correlated with the serum albumin levels, while it was positively correlated with hs‐CRP values. Furthermore, serum albumin levels showed a negative correlation with hs‐CRP levels. We did not find any significant association between the presence of NAFLD and clinical parameters of nutrition. We have shown that NAFLD could be one more possible example of reverse epidemiology in patients undergoing HD. NAFLD may be the missing link that causally ties malnutrition, inflammation, and atherosclerosis syndrome to the morbidity and mortality in patients undergoing HD.     

Investigation of the Importance of Spatial Resolution for Two-Dimensional Shallow-Water Model Accuracy

The importance of spatial resolution for two-dimensional shallow-water model accuracy has been investigated by testing the effect of mesh refinement on two test cases based on laboratory dam-break experiments. A balanced first-order accurate upwind Q-Scheme and a second-order accurate upwind Hancock Monotone Upstream-centered Scheme for Conservation Laws scheme were both first validated on an analytical test, and then applied to the experimental dam-break test cases on four meshes of different density. Simulation results were evaluated through comparison of experimental and computed water level values at several available gauge points. Model sensitivity analysis showed that (1) mesh density was not critical for results accuracy; (2) excessive mesh refinement somewhat deteriorated the results; and (3) optimal spatial resolution was relatively low. Response is shown to be highly complex and no simple relation between spatial resolution and model accuracy has been found.