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This paper aims to present and discuss the requirements for flying targets which sometimes are contradictory to each other and to perform a trade-off analysis before the design activity is started. It also aims to demonstrate conceptual and preliminary design processes using a practical example of PW-61 configuration and to show how results of experimental flight tests using a scaled flying target will be described and analyzed before manufacturing the full scale flying target.

An important part of the paper consists of the selection of tailplane configuration of the flying target UAV to protect some expensive on-board systems against serious damages and to obtain a sufficient dynamic stability, independently of the amount of the petrol in fuel tank. Inverted V-tail, U-tail and H-tail configurations were considered and compared both, theoretically and in-flight experiments.

Flight dynamics models and associated computational procedures were useful both in a preliminary design phase and during the final assessment of the configuration after flight tests. Selection of the tailplane configuration for the flying target UAV is very important to protect some expensive on-board systems against serious damages and to obtain a sufficient dynamic stability, independent of the amount of the petrol in fuel tank.

Flying targets should be speedy, maneuverable, cheap, easy in deployment and multi-recoverable (if not destroyed by live ammunition), must have relatively low take-off weight and an endurance of at least 1 h. This paper can be useful for proper selection of requirements and preliminary design parameters to make the design process more economically effective.

This paper presents very efficient methods of assessing the design parameters of flying targets, especially in an early stage of the design process. Stability computations are performed based on equations of motion and are supplemented by flight tests using the scaled flying models. It can be considered as an original, not typical, but very practical approach because it delivers lots of data in the early design stages at relatively low cost.

To investigate two explanations for how variations in social network structure might produce differences in cognitive and perceptual orientation. One explanation is that the extent to which structures lead people to feel strong social bonds encourages holism. The other is that the extent to which a network leads individuals to be concerned about distal network relations leads to holistic thinking.

An experimental study in which participants interacted in three-person networks of negotiated (with or without a one-exchange rule), generalized, or productive exchange before being administered the framed-line test, a common measure of cognitive and perceptual orientation.

Participants in network structures more likely to lead participants to be concerned about what was happening in relationships in the network of which they were not part performed relatively more holistically on the framed-line test. However, these effects did not extend to both modules of the test, and a check on the ordering of networks as reflecting concern with distal network relationships failed.

The experimental design was structured such that only one of the presented explanations could possibly be supported, whereas they both could be correct. Nevertheless, results do indicate that cognitive orientation did respond to variations in network structure.

Explanations for cultural differences typically implicate social structure, although the explanations often cannot be directly tested. Results show that social structure can produce effects that mirror differences thought to reflect profound cultural variations.

Proposes the application of novel control strategy in power transistors (insulated gate bipolar transistors – IGBT) based on AC/DC/AC converter with active filtering function. Seeks to investigate the possibilities of operating drive system under distorted line voltage with unity power factor and reduced dc‐link capacitor.

A novel control strategy is proposed based on direct power and direct torque control with space vectors modulators scheme which seems to be most promising. This method is investigated, implemented and examined in the laboratory setup. Different working conditions are taken into consideration.

Provides information how the proposed system works under motoring and regenerating modes. Good behaviors of the system in steady state in transience are shown. Very good stabilization of the dc‐link voltage under transient is achieved. Almost sinusoidal line current is obtained. Very good compensation of nonlinear load is also achieved.

This is not an exhaustive investigation. The system should be tested with different input inductances (or LCL filters) and with reduced dc‐link capacitor. Moreover, laboratory tests with higher power should be performed in the future.

A useful source of information and an example of how a fully controlled AC/DC/AC converter with active filtering function works. It could be an important basis for a prototype for industry.

Although the direct power control with space vector modulator (DPC‐SVM) and direct torque control with space vector modulator (DTC‐SVM) schemes have been described in the literature separately, it is analyzed for the first time and investigated together for control of the AC/DC/AC converter. Additionally, active filtering provides a feature of power compensation. It could be the basis for a clean power system design.

The purpose of this paper is to consider both sides of a back‐to‐back AC‐DC‐AC interface.

The paper presents a mathematical analysis, simulation, laboratory test in scaled model.

The two main findings comprised concept of control methods for grid AC‐DC‐AC converter applied in renewable energy sources with variable speed operation under distorted grid. Active filtering functionality in case of non‐linear current of a parallel load. Second, a control algorithm dedicated for two‐level AC‐DC converter applied in industrial networks with high‐order harmonics compensation working under hard conditions – balanced and unbalanced voltage dips.

The paper shows preliminary results for AC‐DC‐AC converter and active filter (AF) during voltage dips and for harmonics compensation. Control methods and/or topology should be improved and tested in scale and after at high‐power system.

Power quality supplied/received to/from the grid can be increased. In case of low‐cost system only AF can be applied to existing non‐linear receivers. Moreover, in case of full AC‐DC‐AC converter energy saving and production is possible.

Presented control methods give satisfactory results. Paper presents laboratory results for grid and machine side two different power circuits during steady states and transients. Moreover, active filtering operation during voltage dips is presented.

To provide a selective bibliography for researchers working with bulk material forming (specifically the forging, rolling, extrusion and drawing processes) with sources which can help them to be up‐to‐date.

A range of published (1996‐2005) works, which aims to provide theoretical as well as practical information on the material processing namely bulk material forming. Bulk deformation processes used in practice change the shape of the workpiece by plastic deformations under forces applied by tools and dies.

Provides information about each source, indicating what can be found there. Listed references contain journal papers, conference proceedings and theses/dissertations on the subject.

It is an exhaustive list of papers (1,693 references are listed) but some papers may be omitted. The emphasis is to present papers written in English language. Sheet material forming processes are not included.

A very useful source of information for theoretical and practical researchers in computational material forming as well as in academia or for those who have recently obtained a position in this field.

There are not many bibliographies published in this field of engineering. This paper offers help to experts and individuals interested in computational analyses and simulations of material forming processes.