Einige Mehle und Brote aus Hungergegenden Russlands

Ohne Zusammenfassung     

A tele-operated mobile ultrasound scanner using a light-weight robot.

This paper presents a new tele-operated robotic chain for real-time ultrasound image acquisition and medical diagnosis. This system has been developed in the frame of the Mobile Tele-Echography Using an Ultralight Robot European Project. A light-weight six degrees-of-freedom serial robot, with a remote center of motion, has been specially designed for this application. It holds and moves a real probe on a distant patient according to the expert gesture and permits an image acquisition using a standard ultrasound device. The combination of mechanical structure choice for the robot and dedicated control law, particularly nearby the singular configuration allows a good path following and a robotized gesture accuracy. The choice of compression techniques for image transmission enables a compromise between flow and quality. These combined approaches, for robotics and image processing, enable the medical specialist to better control the remote ultrasound probe holder system and to receive stable and good quality ultrasound images to make a diagnosis via any type of communication link from terrestrial to satellite. Clinical tests have been performed since April 2003. They used both satellite or Integrated Services Digital Network lines with a theoretical bandwidth of 384 Kb/s. They showed the tele-echography system helped to identify 66% of lesions and 83% of symptomatic pathologies.     

Constructing Second-Order Models of Mechanical Systems from Identified State Space Realizations. Part II: Numerical Investigations

This paper presents various numerical investigations about obtaining physical parameters of second-order mechanical systems using the algorithms that were investigated in detail in the first part of this study. To discuss in detail the computational aspects and the limitations of each of these algorithms, the first example presented is the identification of the physical parameters of a three-degrees-of-freedom (3-DOF) system. It is shown that when the input/output data used in the identification is noise free, then each of the methodologies can exactly retrieve the second-order coefficient matrices, provided that the sensor/actuator requirements imposed by each of them are satisfied accordingly. To investigate the effects of noisy data on the identified second-order parameters, Monte Carlo simulations are performed on the 3-DOF system at different noise-to-signal ratios, and the results show that the three algorithms perform quite satisfactorily. The analysis is then extended to a 120-DOF, three-dimensional structural system, and in this part of the presentation issues such as modal truncation, insufficient instrumentation, and alternative colocation requirements are discussed. The last section of the paper is devoted to a detailed evaluation of the performance of each of the algorithms discussed in this work.     

Fault-Threshold Prediction with Linear Programming Methodologies

This paper presents a new experimental methodology that operates on a series of programs structural parameters. We calculated some simple metrics on these parameters and then we applied linear programming techniques on them. It was therefore possible to define a model that can predict the risk level of a program, namely how prone it is to containing faults. The new system represents the software files as points on an n-dimensional space (every dimension is one of the structural attributes for each file). Starting from this model the problem to find out the more dangerous files is brought back to the problem to separate two sets in R ⁿ . A solution to this linear programming problem was achieved by using the MSM-T method (multisurface method tree), a greedy algorithm, which iterative divides the space in polyhedral regions till it reaches an empty set. The classification procedure is divided in two steps: the learning phase, which is used to tune the model on the specified environment and the effective selection. It is, therefore, possible to divide the n-dimensional space and find out the risk-regions of the space, which represent the dangerous files All the process was tested in an industrial application, to validate the soundness of the methodology experimentally. A comparison between linear programming and other risk definition techniques was provided.     

A Review of Literature: Individual Blame vs. Organizational Function Logics in Accident Analysis

When an accident happens in an organization, two different approaches are possible to explain its origin and dynamics. The first approach, called individual blame logic aims at finding the guilty individuals. The second approach, called organizational function logic aims to identify the organizational factors that favoured the occurrence of the event. This article compares the two different logics of inquiry, the consequences that they produce, in particular in the case of accidents caused by unintentional actions. Though favoured by the scientists, the organizational function logic approach is in real life usually beaten by the individual blame logic. Reviewing the literature, this article brings together the arguments for using the organizational function logic from the perspective that learning from accidents is necessary to prevent them from happening again.     

Grafting of selected presynthesized macromonomers onto various dispersions of silica particles

A new process was developed which enables one to obtain surface‐modified silica with a high heavy metal ion complexing ability. The synthetic approach is based on grafting of vinyl‐terminated macromonomers onto silica via covalent bonding. A proper selection of the macromonomer structure, molecular weight, and molecular weight distribution allows materials to be obtained with a range of desirable properties. The process has been tested on various dispersions (ranging from 35 and 200 μm) of silica particles and two structurally related macromonomers. Native silica and the resulting mixed organic–inorganic products were fully characterized by IR spectroscopy, SEM, yield of grafting (elemental analysis and calcination), density (helium pycnometry), specific surface area (BET method), and pore size (gas adsorption and mercury porosimetry) measurements. It was found that the corresponding polymers are effectively grafted onto the surface; the density, surface area, and pore size of the silica particles decrease with polymer grafting. Preliminary results on metal‐ion uptake indicate that polymer‐grafted silica exhibits an excellent complexing ability. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1287–1296, 2002     

Kinetics and Mechanism of Formation of Barium Zirconate from Barium Carbonate and Zirconia Powders

The formation of BaZrO₃ from very fine (70–90 nm) ZrO₂ powders and coarser (∼1 μm) BaCO₃ powders has been studied in dry and humid air up to 1300°C using TGA/DTA, XRD, SEM, TEM, and EDS microanalysis. In the temperature range 900°–1100°C, barium is rapidly transported at the surface of the ZrO₂ particles and reacts, forming BaZrO₃. The compound grows as a concentric layer with gradual consumption of the central ZrO₂ particle. The overall formation kinetics of BaZrO₃ is well described by a diminishing core model, and the most likely rate-determining step is a phase-boundary process at the ZrO₂–BaZrO₃ moving interface. The size and shape of the final particles is generally determined by the morphology of the starting ZrO₂ particles and not by that of the BaCO₃. The reaction is faster in humid air than in dry air, and the activation energy decreases from 294 kJ·mol⁻¹ (dry air) to 220 kJ·mol⁻¹ (humid air). When the fraction reacted is >80–90 mol%, the reaction rate rapidly decreases.     

Flavanones in Citrus fruit: Structure–antioxidant activity relationships

Epidemiological surveys have shown an inverse relationship between the intake of fruit and the incidence of coronary heart disease and some type of cancer. Data found in the literature regarding the flavonoids in general while this study focuses on flavanones, a subclass of flavonoids which occurs in Citrus fruit. The aim of this work is to elucidate the antioxidant or pro-oxidant behaviours of some common flavanones and to determine their activity–structure relationships as antioxidant using the crocin bleaching inhibition assay. The compounds studied were regarding both the aglycon form and the glycoside form. Data evidence that the substitution of the 7th OH group of the flavanones by a neohesperidoside influences the relationship between structure and antioxidant activity. In fact, the 3′,4′-catechol structure and the O-methylation, in the aglycone forms, do not result significant. On the other hands, in the glycosylate forms, the 3′,4′-catechol structure noticeably increases the antioxidant power and the O-methylation decreases the antioxidant activity. The influence of the O-glycosylation with a rutinose molecule is neglectable.     

水堆安全壳内气体分布模拟计算

本工作采用TH3SL程序对水堆事故后安全壳内的气体分布及蒸汽冷凝进行了随机模拟。校验计算表明 :此程序的模拟结果是可信的     

Surface chemical analysis of poly(ε‐caprolactone)–perfluoropolyether–poly(ε‐caprolactone) triblock copolymers by X‐ray photoelectron spectroscopy

The air‐side surface composition of a series of poly(ε‐caprolactone)–perfluoropolyether–poly(ε‐caprolactone) triblock copolymers with different compositions and block lengths have been studied by angle‐dependent X‐ray photoelectron spectroscopy (XPS). The weight percentage of the perfluoropolyether (PFPE) and polycaprolactone (PCL) blocks, and ethylene oxide linker (R_H) has been calculated in different ways: from C1s, O1s and F1s photoemission peaks and by line fitting of the C1s and O1s envelopes. The atomic sensitivity factors and the parameters used to fit the peak envelopes have been experimentally determined using some reference materials. A critical discussion of the different methods used in the surface characterization and the degradation of PFPE segments, induced by irradiation beam, have been also reported. A large excess of PFPE with respect to the bulk composition was observed in all samples, and the angular dependence of the XPS signal demonstrated that the content of the fluorinated block segment increased by decreasing the sampling depth. The PFPE surface concentration was also decreased by increasing the PCL/PFPE ratio, but the surfaces of the samples were still dominated by PFPE segments for copolymers with a bulk PFPE composition lower than 10%. Moreover, copolymers with similar PCL/PFPE bulk ratios but with different PFPE block lengths, showed similar PFPE surface composition when the number‐average molecular weight (M_n) was 2000 and 3200 g mol^?1, while that observed for copolymers containing PFPE block with M_n 900 g mol^?1 was lower. Copyright © 2003 Society of Chemical Industry