Recent Developments in the Theory of Learning and the Identity of the Manager

One view of the manager is as a ‘practical’ scientist. In contrast to this image, many managers do not see themselves in this light and are uncomfortable with the notion that to be successful they should act in purely a mechanistic ‘scientific’ way. Alternative to this view is to see the manager as a ‘reflective practitioner’, but this is only one of a number of metaphors that might be used. This paper introduces the metaphor of the manager as a ‘practical author’ and puts the way language is used within social contexts centre stage. The paper does not dismiss or undervalue the concept of the reflective practitioner but rather, offers an additional image thought to be useful to managers when considering how they might act. Three examples of how a manager might be developed using these ideas are given. Social constructivist accounts of Managerial Activity. Management Learning and Organisational Development

Uplatňování principů strategického managementu ve firmě CS CABOT, s.r.o.

Import 20/04/2006Prezenční výpůjčkaVŠB - Technická univerzita Ostrava. Ekonomická fakulta. Katedra (152) podnikohospodářsk

Effects of accelerated climatic aging on volume and surface resistivity of glass fiber reinforced thermoset composites

This paper is focused on the analysis of selected dielectric parameters stability under the conditions of selected accelerated climatic aging. This stability is analyzed for glass fiber reinforced composites with different thermosetting matrix suitable for the production of electrical insulating and also construction elements. Different types of thermosetting resins (epoxy and polyurethane resins) were chosen for the preparation of composites, which are the subject of the presented experiment. Tested composites were firstly characterized in the delivered state and then after the accelerated climatic aging. Important dielectric parameters were evaluated, which are the volume resistivity and the surface resistivity. Two different tests of accelerated climatic aging were realized. The first one was Temperature/humidity cyclic test, which consists of alternated intervals (i) under the temperature of 55 °C and the humidity of 93 %RH and (ii) under the temperature of 25 °C and the humidity of 97.5 %RH. The second one was Damp heat steady state test when samples were exposed to the temperature of 85 °C and the humidity of 85 %RH continuously for 1000 hours. Based on the measured data of resistivities, prospective materials were selected for further activities leading to the production of construction elements with also good electrical insulating properties and with their minimal affection by simulated climatic conditions

Evaluation of structure influence within the context of water diffusion and surface current of glass reinforced polymer composites for HV insulation

This article deals with the issue of selected polymer composites consisting of a thermoset matrix and reinforcing glass fibers. These composites are designed for high voltage applications as an electrical insulating material with high mechanical durability. Three composites with a significantly matrix, specifically, epoxy, polyurethane and polyester resin, are selected with an emphasis on usability in the technical practice. Key properties of tested composites are dielectric and mechanical properties and from this point of view the homogeneity of prepared specimens is very important. An important influencing factor, which is a frequent cause of deterioration of material properties, is a higher lev-el of moisture or even direct contact with water leading to the diffusion of water into the material structure. The main subject of presenting research is therefore the assessment of the water diffusion impact on processed material in the relation to the resistance of the tested specimens to the applied high voltage. Tested composite structures are observed by optical microscopy and the computed tomography is used for analysis of the material volume. Purely surface dielectric properties in the delivered state were evaluated based on the measurement of surface current at a constant direct or alternating test voltage. Results of surface current measurement for all composites in the delivered state show minimal differences between composites. The minimal dependence, primarily for composite with polyurethane, of the water diffusion test results on the internal structure and on the character of voids within tested specimens is determined. The lowest level of voids was found for epoxy matrix composite, but this material did not pass the water diffusion test. Differences of the HV resistance obtained from the water diffusion test are most likely caused mainly by different chemi-cal resistance of resins against boiling slightly alkaline aqueous solution

Hybrid steel–composite cross-arm for distribution power lines

This paper describes the development of electrically insulating hybrid steel–composite cross-arm for mediumvoltage overhead distribution power lines with three conductors. The main goal was to achieve substantial weight savings ompared to a common steel cross-arm with three ceramic insulators widely used in the Czech Republic. The structure has been designed as a combination of two main composite components – a pultruded horizontal profile and a braided vertical conical tube. These components are connected by a steel locking component which also serves for attaching the whole cross-arm to common concrete utility poles. The hybrid cross-arm is conceived to insulate electrical current in the default configuration thanks to the properties of the glass fiber reinforced composite materials, yet additional insulating elements can be used to further increase the electrical insulation distance. The materials and components used for the construction are chosen by combining finite element simulations of mechanical and electrical behavior with experimental testing and verification of important characteristics on selected substructures. The final design of the cross-arm is then manufactured and subjected to long-term testing in real-life environmental conditions. The achieved reduction of weight exceeds 50% while maintaining the mechanical rigidity and strength of the steel solution as well as the required insulation properties. The future trend of the cross-arm development is aiming at the weight reduction and increase of manipulation capabilities resulting in lowering many additional costs. In this work the designed cross-arm has half the weight of the original one

In-orbit commissioning of Czech nanosatellite VZLUSAT-1 for the QB50 mission with a demonstrator of a miniaturised lobster-eye X-ray telescope and radiation shielding composite materials

This paper presents the results of in-orbit commissioning of the first Czech technological CubeSat satellite of VZLUSAT-1. The 2U nanosatellite was designed and built during the 2013 to 2016 period. It was successfully launched into Low Earth Orbit of 505km altitude on June 23, 2017 as part of international mission QB50 onboard a PSLV C38 launch vehicle. The satellite was developed in the Czech Republic by the Czech Aerospace Research Centre, in cooperation with Czech industrial partners and universities. The nanosatellite has three main payloads. The housing is made of a composite material which serves as a structural and radiation shielding material. Anovel miniaturized X-Ray telescope with lobster-eye optics and an embedded Timepix detector represents the CubeSat's scientific payload. The telescope has a wide field of view. VZLUSAT-1 also carries the FIPEX scientific instrument as part of the QB50 mission for measuring the molecular and atomic oxygen concentration in the upper atmosphere

Grayscale and color Doppler features of testicular lymphoma

Pooled data from 16 radiology centers were retrospectively analyzed to seek patients with pathologically proven testicular lymphoma and grayscale and color Doppler images available for review. Forty-three cases were found: 36 (84%) primary and 7 (16%) secondary testicular lymphoma. With unilateral primary lymphoma, involvement was unifocal (n = 10), multifocal (n = 11), or diffuse (n = 11). Synchronous bilateral involvement occurred in 6 patients. Color Doppler sonography showed normal testicular vessels within the tumor in 31 of 43 lymphomas (72%). Testicular lymphoma infiltrates through the tubules, preserving the normal vascular architecture of the testis. Depiction of normal testicular vessels crossing the lesion is a useful adjunctive diagnostic criterion