Autonomous power supply with higher EMC requirements

Tato práce se zabývá návrhem mechanické části, elektrické části a otestováním autonomního napájecího zdroje. Skládá se z výběru materiálů, návrhu tvarů a výpočtů průchodek pro obal zařízení pro zajištění potřebných elektromagnetických vlastností. Dále obsahuje volbu elektronických součástí, porovnání DC-DC měničů a konstrukci filtrů se zaměřením na co nejvyšší elektromagnetickou odolnost a co nejnižší elektromagnetické emise.This paper deals with design of mechanical and electrical components of autonomous power supply and its testing. It consists of selecting of the materials, draft of shapes and calculations of feed-throughs for the source container to ensure the required electromagnetic characteristics. It also includes the selection of electronic components, comparison of DC-DC converters and filter design with focus on the highest electromagnetic immunity and the lowest electromagnetic emissions.

Das dynastische Denken in der Historia Augusta

Idealno nasledovanje vladarjev, ki ga indirektno zagovarja Historia Augusta, ni dinastično nasledstvo. Misel pisca je logična, posebej ker je bil naklonjen senatu. Ta je namreč smatral volitev vladarjev za svojo nesporno in samo po sebi umevno pravico. Hkrati pa si je bil pisec dela Historia Augusta na jasnem, da je zaradi pohlepa po oblasti nemogoče odstraniti iz političnega življenja dinastično misel in tudi ne zahteve vojske po umeščanju vladarja. Pisec zahteva, da ima senat aktivno udeležbo pri volitvi vladarja, kajti zgolj senat lahko zagotovi, da bi oba principa ne bila zlorabljena. Historia Augusta interpretira dinastični princip v bistvu kot prakso, da senat iz svojih vrst in neodvisno izvoli vladarja, ne da bi mu hkrati dodelil pravico, da to oblast avtomatično prenese na sina ali drugega sorodnika. Senat sam in vodilne osebnosti, izvirajoče iz plemenitih senatskih rodbin, morajo odločiti, ali naj bo nov vladar izvoljen po dinastični poti ali naj raje odločajo tehnokratske in vojaške sposobnosti. Nepotrebno je dokazovati, da ni bilo nikakih izgledov, da bi se v pozno antični družbi, v kateri je igrala vojaška oblast odločilno notranje politično vlogo, ta naziranja uveljavila. Take utopične ideje so spričevale zgolj brezizgleden položaj tistih slojev, katerih interese je delo Historia Augusta skušalo braniti, in to so bili starorimsko nastrojeni senatorski sloji v metropoli sami

Regulation system for climatic test chambers

Práce obsahuje 5 hlavních částí. První se věnuje obecnému popisu a vlastnostem klimatických komor, jejich jednotlivým částem a jak tyto části fungují. Druhá část se detailně věnuje komoře Angelantoni CH 340. Detailně je zde popsáno, jak komora funguje a popis této komory je až do jednotlivých součástí. Třetí část se věnuje projektu rekonstrukce komory, jaké jsou možnosti rekonstrukce a jakou metodou se komora rekonstruovala. Čtvrtá část popisuje hardware, který se musel zvolit a vyměnit a které části komory se musely upravit. V poslední části je popis programu, který komoru po rekonstrukci ovládá.This paper contains 5 main parts. The first deals with the general description and properties of the climatic chambers, their individual parts and how these parts work. The second part deals with the chamber of Angelantoni CH 340. In detail is described how the chamber works and there is description of this chamber up to individual parts. The third part deals with the reconstruction project, the possibilities of reconstruction and the method that the chamber reconstructed. The fourth part describes the hardware that had to be selected and replaced and which parts of the chamber had to be modified. In the last part is a description of the program that controls the chamber after the reconstruction.

TRAFFIC INTENSITY CHANGES AND SPATIAL DISTRIBUTION OF SUBURBANIZATION

Příspěvek se zabývá projevem zvýšené míry intenzity osobní automobilové dopravy na suburbanizaci mezi územím města Olomouce a jeho zázemím. Cílem výzkumu bylo na základě dat intenzit dopravy (Celostátní sčítání dopravy v letech 2000 a 2005) a autory provedeného měření v roce 2010 provést temporální analýzu intenzit dopravy a výsledné změny porovnat s prostorovou diferenciací suburbanizace v zázemí města Olomouce.The paper deals with an increase of car traffic intensity within the area of Olomouc city and its neighborhoods. The aim of the research was temporal analysis of traffic volumes and the resulting changes compared with the spatial differentiation of suburbanization in the hinterland of the city of Olomouc. Input datasets were data traffic volumes of traffic census in 2000 and 2005 and field research of authors in 2010

In vivo wear of CAD-CAM composite versus lithium disilicate full coverage first-molar restorations: a pilot study over 2 years

OBJECTIVES To present a digital approach to measure and compare material wear behavior of antagonistic first molar restorations made of an experimental CAD/CAM composite (COMP) and lithium disilicate ceramic (LS2) in patients with reconstructed vertical dimension of occlusion (VDO) after generalized hard tissue loss. METHODS A total of 12 patients underwent complete full jaw rehabilitation with full occlusal coverage restorations made either of COMP or LS2. The first molar restorations (n = 48) were chosen for wear examination. At annual recall appointments, polyether impressions were taken, and resulting plaster casts were digitalized using a laboratory scanner. Mean observation period was 371 days for first and 769 days for second year. The resulting 96 datasets were analyzed by superimposition of 3-D datasets using an iterative best-fit method. Based on the superimposition data, the wear rates of the occlusal contact areas (OCAs) were calculated. RESULTS For antagonistic restorations made of COMP, the average wear rate was 24.8 ± 13.3μm/month, while for LS2, it was 9.5 ± 4.3μm/month in first year, with significant~differences (p < 0.0001) between the materials. In second year, monthly wear rates decreased significantly for both materials: COMP (16.2 ± 10.7μm/month) and LS2 (5.5 ± 3.3μm/month). Statistical comparison between wear time showed significant differences for both materials: COMP p < 0.037 and LS2 p < 0.001. A logarithmic fit (COMP R2 = 0.081; LS2 R2 = 0.038) of the data was calculated to estimate the wear progression. SIGNIFICANCE In patients with reconstructed VDO, restorations made of LS2 show a more stable wear behavior than ones out of experimental CAD/CAM composite. In cases of complete rehabilitation, load bearing CAD/CAM-composite restorations should be critically considered for application due to their occlusal wear behavior. However, when choosing a restorative material, not only the functional occlusal stability should be taken into account but also the prospect of minimally invasive treatment with maximum preservation of natural tooth structures

Incidental vertebral fracture prediction using neuronal network-based automatic spine segmentation and volumetric bone mineral density extraction from routine clinical CT scans.

OBJECTIVES To investigate vertebral osteoporotic fracture (VF) prediction by automatically extracted trabecular volumetric bone mineral density (vBMD) from routine CT, and to compare the model with fracture prevalence-based prediction models. METHODS This single-center retrospective study included patients who underwent two thoraco-abdominal CT scans during clinical routine with an average inter-scan interval of 21.7 ± 13.1 months (range 5-52 months). Automatic spine segmentation and vBMD extraction was performed by a convolutional neural network framework (anduin.bonescreen.de). Mean vBMD was calculated for levels T5-8, T9-12, and L1-5. VFs were identified by an expert in spine imaging. Odds ratios (ORs) for prevalent and incident VFs were calculated for vBMD (per standard deviation decrease) at each level, for baseline VF prevalence (yes/no), and for baseline VF count (n) using logistic regression models, adjusted for age and sex. Models were compared using Akaike's and Bayesian information criteria (AIC & BIC). RESULTS 420 patients (mean age, 63 years ± 9, 276 males) were included in this study. 40 (25 female) had prevalent and 24 (13 female) had incident VFs. Individuals with lower vBMD at any spine level had higher odds for VFs (L1-5, prevalent VF: OR,95%-CI,p: 2.2, 1.4-3.5,p=0.001; incident VF: 3.5, 1.8-6.9,p<0.001). In contrast, VF status (2.15, 0.72-6.43,p=0.170) and count (1.38, 0.89-2.12,p=0.147) performed worse in incident VF prediction. Information criteria revealed best fit for vBMD-based models (AIC vBMD=165.2; VF status=181.0; count=180.7). CONCLUSIONS VF prediction based on automatically extracted vBMD from routine clinical MDCT outperforms prediction models based on VF status and count. These findings underline the importance of opportunistic quantitative osteoporosis screening in clinical routine MDCT data

Association of Thigh Muscle Strength with Texture Features Based on Proton Density Fat Fraction Maps Derived from Chemical Shift Encoding-Based Water-Fat MRI

Purpose: Based on conventional and quantitative magnetic resonance imaging (MRI), texture analysis (TA) has shown encouraging results as a biomarker for tissue structure. Chemical shift encoding-based water–fat MRI (CSE-MRI)-derived proton density fat fraction (PDFF) of thigh muscles has been associated with musculoskeletal, metabolic, and neuromuscular disorders and was demonstrated to predict muscle strength. The purpose of this study was to investigate PDFF-based TA of thigh muscles as a predictor of thigh muscle strength in comparison to mean PDFF. Methods: 30 healthy subjects (age = 30 ± 6 years; 15 females) underwent CSE-MRI of the lumbar spine at 3T, using a six-echo 3D spoiled gradient echo sequence. Quadriceps (EXT) and ischiocrural (FLEX) muscles were segmented to extract mean PDFF and texture features. Muscle flexion and extension strength were measured with an isokinetic dynamometer. Results: Of the eleven extracted texture features, Variance(global) showed the highest significant correlation with extension strength (p 2adj = 0.712), and Correlation showed the highest significant correlation with flexion strength (p = 0.016, R2adj = 0.658). Multivariate linear regression models identified Variance(global) and sex, but not PDFF, as significant predictors of extension strength (R2adj = 0.709; p 2adj = 0.674; p < 0.001). Conclusions: Prediction of quadriceps muscle strength can be improved beyond mean PDFF by means of TA, indicating the capability to quantify muscular fat infiltration patterns

Texture Features of Proton Density Fat Fraction Maps from Chemical Shift Encoding-Based MRI Predict Paraspinal Muscle Strength

Texture analysis (TA) has shown promise as a surrogate marker for tissue structure, based on conventional and quantitative MRI sequences. Chemical-shift-encoding-based MRI (CSE-MRI)-derived proton density fat fraction (PDFF) of paraspinal muscles has been associated with various medical conditions including lumbar back pain (LBP) and neuromuscular diseases (NMD). Its application has been shown to improve the prediction of paraspinal muscle strength beyond muscle volume. Since mean PDFF values do not fully reflect muscle tissue structure, the purpose of our study was to investigate PDFF-based TA of paraspinal muscles as a predictor of muscle strength, as compared to mean PDFF. We performed 3T-MRI of the lumbar spine in 26 healthy subjects (age = 30 ± 6 years; 15 females) using a six-echo 3D spoiled gradient echo sequence for chemical-shift-encoding-based water–fat separation. Erector spinae (ES) and psoas (PS) muscles were segmented bilaterally from level L2–L5 to extract mean PDFF and texture features. Muscle flexion and extension strength was measured with an isokinetic dynamometer. Out of the eleven texture features extracted for each muscle, Kurtosis(global) of ES showed the highest significant correlation (r = 0.59, p = 0.001) with extension strength and Variance(global) of PS showed the highest significant correlation (r = 0.63, p = 0.001) with flexion strength. Using multivariate linear regression models, Kurtosis(global) of ES and BMI were identified as significant predictors of extension strength (R2adj = 0.42; p &lt; 0.001), and Variance(global) and Skewness(global) of PS were identified as significant predictors of flexion strength (R2adj = 0.59; p = 0.001), while mean PDFF was not identified as a significant predictor. TA of CSE-MRI-based PDFF maps improves the prediction of paraspinal muscle strength beyond mean PDFF, potentially reflecting the ability to quantify the pattern of muscular fat infiltration. In the future, this may help to improve the pathophysiological understanding, diagnosis, monitoring and treatment evaluation of diseases with paraspinal muscle involvement, e.g., NMD and LBP

Real-time spatial characterization of micrometer-sized X-ray free-electron laser beams focused by bendable mirrors

A real-time and accurate characterization of the X-ray beam size is essential to enable a large variety of different experiments at free-electron laser facilities. Typically, ablative imprints are employed to determine shape and size of μm-focused X-ray beams. The high accuracy of this state-of-the-art method comes at the expense of the time required to perform an ex-situ image analysis. In contrast, diffraction at a curved grating with suitably varying period and orientation forms a magnified image of the X-ray beam, which can be recorded by a 2D pixelated detector providing beam size and pointing jitter in real time. In this manuscript, we compare results obtained with both techniques, address their advantages and limitations, and demonstrate their excellent agreement. We present an extensive characterization of the FEL beam focused to ≈1 μm by two Kirkpatrick-Baez (KB) mirrors, along with optical metrology slope profiles demonstrating their exceptionally high quality. This work provides a systematic and comprehensive study of the accuracy provided by curved gratings in real-time imaging of X-ray beams at a free-electron laser facility. It is applied here to soft X-rays and can be extended to the hard X-ray range. Furthermore, curved gratings, in combination with a suitable detector, can provide spatial properties of μm-focused X-ray beams at MHz repetition rate

Ablation of single-crystalline cesium iodide by extreme ultraviolet capillary-discharge laser

Extreme ultraviolet (XUV) capillary-discharge lasers (CDLs) are a suitable source for the efficient, clean ablation of ionic crystals, which are obviously difficult to ablate with conventional, long-wavelength lasers. In the present study, a single crystal of cesium iodide (CsI) was irradiated by multiple, focused 1.5-ns pulses of 46.9-nm radiation delivered from a compact XUV-CDL device operated at either 2-Hz or 3-Hz repetition rates. The ablation rates were determined from the depth of the craters produced by the accumulation of laser pulses. Langmuir probes were used to diagnose the plasma plume produced by the focused XUV-CDL beam. Both the electron density and electron temperature were sufficiently high to confirm that ablation was the key process in the observed CsI removal. Moreover, a CsI thin film on MgO substrate was prepared by XUV pulsed laser deposition; a fraction of the film was detected by X-ray photoelectron spectroscopy.Web of Science65421020