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The aim of this study was to determine the factor structure of Chen and Starost’s self-descriptive scale of intercultural sensitivity. The applied scale was based on the self-assessments of 24attitudes with a five-point Likert scale. A group examination was performed on 621 students in the final grades of primary school. Factor analysis isolated five factors that include students’ intercultural sensitivity: interaction enjoyment, interaction confidence, interaction attentiveness, respect of cultural differences, and interaction engagement. The scale is solidly represented by the main components that explain the variance with 49.18% of the examined phenomenon. The reliability coefficient of the scale on our sample is acceptable and amounts to α=0.820. The Kaiser-Meyer-Olkin sample adequacy index had an index value of K=0.85, and the Bartlett sphericity test was statistically significant χ2=3684,968;df=276; p

The relevance of the work is due to the need to develop new means of highly efficient vibration protection. One such means is a vibration isolator with quasi-zero stiffness. They are quite sensitive elements, so the problem of designing and operating vibration isolators with quasi-zero stiffness is relevant. Nowadays, comprehensive studies on their work within a group have not yet conducted. Purpose of the work is to study the sensitivity of vibration isolators with quasi-zero stiffness to the errors of geometric parameters while their manufacture. Methodology of research. This work is a continuation of the experimental studies of plate-type universal vibration isolators with quasi-zero stiffness. For the research, an analytical study and a computer-based multiple experimental procedure with random input data were used. Results. Analytical studies show that vibration isolators with quasi-zero stiffness are very sensitive objects. Basic properties, such as workload and stiffness under workload, largely depend on key parameters. Vibration isolators of plate type have a very strong dependence of the workload on the external and internal radii, the height of the cone and the wall thickness. The dynamics of a group of vibration isolators was analysed. Due to the deviation of different parameters and the nonlinearity of the power characteristics, the behaviour of the group does not coincide with the average behaviour of one vibration isolator. It has been found that for a group of isolators there is a slight increase in workload. Moreover, deviations in parameters lead to a decrease in stiffness. Conclusions. The high sensitivity of installed vibration isolators with quasi-zero stiffness proves that they require careful attention and high precision in manufacturing. The resulting deviations of the behaviour of a group of vibration isolators from the behaviour of a single vibration isolator indicate the need to enter appropriate corrections when designing them, otherwise this may lead to loss of stability and instability of the equipment, which should be avoided.

A dual burner experiment is used to investigate how flow interactions affect local flame-flame interaction in turbulent premixed flames. The presence of adjacent flows influences the local structure of these flames and understanding the sensitivity of these flames to adjacent flows is essential for multi-nozzle combustion devices. To study this sensitivity, a high-aspect-ratio Bunsen flame operating at a constant flow velocity is placed adjacent to an identical burner with non-reacting flow at varying velocities. High-speed OH-planar laser induced fluorescence and stereoscopic-particle image velocimetry measurements are performed to capture flame-front locations and velocity fields. A non-rigid image registration technique is used to calculate the local flame-area variations that occur due to topological differences, and conditional statistics are extracted to relate the local behavior to changes observed in the global behavior of the flames. Extracted flame curvatures and time-averaged progress variables conditioned on flame-flame interactions show differences existing in the inner and outer flame branches near the flame-attachment region. Statistics of these results are presented and compared for all test cases.

Air traffic is important to our society and guarantees mobility especially for long distances. Air traffic is also contributing to climate warming via emissions of CO2 and various non-CO2 effects, such as contrail-cirrus or increase in ozone concentrations. Here we investigate the climate impact of a future aircraft design, a multi fuel blended wing body (MF-BWB), conceptually designed within the EU-project AHEAD. We re-calculate the parameters for the contrail formation criterion, since this aircraft has very different characteristics compared to conventional technologies and show that contrail formation potentially already occurs at lower altitudes than for conventional aircraft. The geometry of the contrails, however, is similar to conventional aircraft, as detailed Large-Eddy-Simulations show. The global contrail-cirrus coverage and related radiative forcing is investigated with a climate model including a contrail-cirrus parameterisation and shows an increase in contrail-cirrus radiative forcing compared to conventional technologies, if the number of emitted particles is equal to conventional technologies. However, there are strong indications that the AHEAD engines would have a substantial reduction in the emission of soot particles and there are strong indications that this leads to a substantial reduction in the contrail-cirrus radiative forcing. An overall climate impact assessment with a climate-chemistry response model shows that the climate impact is likely to be reduced by 20% to 25% compared to a future aircraft with conventional technologies. We further tested the sensitivity of this result with respect to different future scenarios for the use of bio fuels, improvements of the fuel efficiency for conventional aircraft and the impact of the number of emitted soot particles on the radiative forcing. Only the latter has the potential to significantly impact our findings and needs further investigation. Our findings show that the development of new and climate compatible aircraft designs requires the inclusion of climate impact assessments already at an early stage, i.e. pre-design level.

Seepage is an important yet rarely modeled or quantified phenomenon in mixed traffic streams. It describes situations where smaller vehicles do not line up but rather “seep” through a queue of stationary or almost stationary vehicles. This contribution introduces seepage into an agent-based transport simulation model. In order to allow vehicles to seep, the traditional first-in-first-out queue model is modified such that in the free flow regime, faster vehicles can overtake slower vehicles and in the congested regime, slower vehicles can overtake faster vehicles. The model is validated with the help of fundamental diagrams. Its sensitivity is investigated by comparing the impact of different shares of smaller vehicles on the speed-density relation in the mixed traffic streams. A case study of the evacuation of Patna, India under mixed traffic conditions with seepage demonstrates the overall approach.

Unsichere Randbedingungen haben einen grosen Einfluss auf das Ergebnis von Gebaudesimulationen. Trotzdem werden Unsicherheitsbewertungen und Sensitivitatsanalysen bisher in der Planungspraxis und auch in wissenschaftlichen Untersuchungen selten durchgefuhrt. In diesem Beitrag wird eine Methodik zur Unsicherheitsbewertung und Sensitivitatsanalyse fur thermische Gebaudesimulationen vorgestellt. Diese wird exemplarisch angewendet, um Einsatzmoglichkeiten darzustellen. Potentielle Einsatzgebiete sind Simulationen im Planungsprozess von Gebauden sowie eine simulationsbasierte Gebaudebetriebsanalyse. Die Anwendung der Methodik kann dazu beitragen, den Planungsprozess und den Gebaudebetrieb zu verbessern. Methodology for uncertainty and sensitivity analysis for building performance simulation. Uncertainties in simulation input have a big influence on building performance simulation results. Nevertheless, uncertainty quantification and sensitivity analysis is not commonly applied in the design practice and also in scientific research. In this paper a methodology for uncertainty quantification and sensitivity analysis is introduced. The methodology is applied to an example case to illustrate possible applications. It can be used within the design stage of buildings as well as for simulation -based building operation analysis. The methodology can improve the design process as well as building operation.

The research unit of pharmaceutical analytical chemistry (PAC) has been active in the field of separation sciences for many years. Liquid chromatography (LC) and its latest improvements such as ultra-high performance chromatography (UHPLC) and supercritical fluid chromatography (SFC) are deeply and thoroughly studied, from a fundamental viewpoint to its various application capabilities. Electro-driven separations such as capillary electrophoresis (CE) are also a major field of interest, especially for macromolecules, and low cost. All these techniques are investigated with various detection modes including mass spectrometry (MS) for various applications where high sensitivity and selectivity is needed. Extracting the relevant information from the overwhelming amount of data generated by modern analytical platforms has become an important issue for knowledge discovery in various research fields. The appropriate treatment of such data is therefore of crucial importance to provide valuable information. Numerous works in our research group have demonstrated the usefulness of statistical and mathematical methodologies to improve quality of the results. Therefore, well-established chemometric approaches (e.g. design of experiments, multivariate data analysis, etc.) are implemented to optimize the analytical process from method development to data analysis.

In this paper, an investigation into the use of Flexible ac Transmission Systems (FACTS) devices to aid damping of low-frequency inter-area oscillations in longitudinal power systems is presented. A linear model of VSC-based FACTS devices that takes into account the dynamics of dc links is developed and incorporated into a production-grade software for small signal analysis of large power systems. Based on this representation, a unified framework for modal power oscillation flow studies is then developed to analyze the sensitivity of modal behavior to FACTS control action. With this method, the transmission corridors and system parameters having a large contribution to critical system oscillations modes are determined. The method is particularly well suited for investigating inter-system oscillations in large-scale power systems with embedded FACTS controllers The utilized methodology is tested on a practical 45-machine Mexican system that includes several major static VAR compensators. Control mode implementations are discussed and tested and comparisons with existing technologies are presented.

The provision of information to the public about current levels of the erythemally effective UV radiation is an important issue in health care. The quality of promoted values is therefore of special importance. The atmospheric parameter which affects the erythemally effective UV radiation under clear sky most is the total ozone content of the atmosphere. In this paper we examined the sensitivity of the erythemally effective irradiance and daily radiant exposure to the temporal variability of total ozone on time scales from 1 to 15 days. The results show that the sensitivity is highest for the first 24 h. Larger time scales do not exhibit a similar influence. Total ozone measurements of the previous day may already cause uncertainties higher than 0.5 UV index (UVI) independent of the geolocation. For comparison, a temporal persistence of 15 days may cause uncertainties of 1.2 UVI at 50 degrees N, 1 UVI at 30 degrees S and less than 1 UVI at the equator. The results of this study allow finding the necessary temporal resolution of total ozone values when a certain accuracy for the UVI or for the purpose of sun protection is required. The results are compared with those of two preceding studies where we quantified the influence of measurement uncertainties and spatial total ozone variability to the erythemally effective irradiance at noon and to the daily dose. We conclude that temporal variability of total ozone is the most critical issue, but also measurement uncertainties do have a noticeable influence on the erythemally effective radiation.

The noise performance of the force sensor is crucial for optimizing the resolution in non-contact atomic force microscopy. Sensing forces in vacuum and low temperatures is even more demanding than at ambient conditions. Here we analyze the noise performance and the sensitivity of a force sensor based on a quartz tuning fork of which one of the prongs is fixed (qPlus sensor). The noise characteristic of the qPlus sensor, optical and piezoresistive detection schemes at room temperature are compared and the qPlus sensor is investigated at low temperatures. The frequency variation of quartz tuning forks as a function of temperature is experimentally determined for the temperature range from 4 to 300 K.

The principles of probabilistic fracture mechanics are briefly described. It is concluded that the lack of input data prohibits the derivation of absolute reliability numbers. The concept is, however, applicable to sensitivity studies. As one example, a crack generation model is explained, where the crack size distribution is derived from very simple geometrical considerations, but taking into account the real fabrication process.