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921.
The literature on management control has expanded considerably in the past few decades, yet only a limited number of publications have been devoted to multi-project organizations (MPOs). This is somewhat a problem given the increasing rise and importance of project-based structures and the role of project management as a significant part of many firms' management control system. This paper elaborates on a contingency framework of management control in MPOs and aims at investigating the control issues that call for holistic frameworks of control mechanisms. Relying on a comparative case study, the analysis shows how control mechanisms are deployed and what implications different choices of management control systems have on the organizational structure of MPOs. In particular, the paper addresses the importance technical complementarities, and the role of ‘project interdependencies’ and ‘project openness’ for the design of management control system. 相似文献
922.
In Germany, over 7000 professional athletes from different sport sectors must undergo regular doping controls. As is the case with many other nations, Germany relies upon a system recommended by the World Anti-Doping Agency (WADA) to coordinate and initiate these controls. Known as the Anti-Doping Admission and Administration System, or ADAMS for short, the system requires athletes to submit their future regular whereabouts via browser, up to three months in advance. This allows the Doping Control Officer (DCO) to be able to locate the athlete without prior notice. The flip side, however, is that, since its introduction in 2007, ADAMS has not only been severely criticized by athletes themselves for its lack of usability, but has also come under attack by data-privacy experts accusing this system of breaching multiple data privacy laws. 相似文献
923.
Matija Varga Andreas Mehmann Josip Marjanovic Jonas Reber Christian Vogt Klaas Paul Pruessmann Gerhard Tröster 《Advanced materials (Deerfield Beach, Fla.)》2017,29(44)
Stretchable conductors based on eutectic gallium–indium (eGaIn) alloy are patterned on a polychloroprene substrate (neoprene foam) using stencil printing. By tuning the amount of eGaIn on the neoprene substrate, different strain‐sensitivity of electrical resistance is achieved. Conductors with a layer of eGaIn, which adsorbs to the walls of 60–100 µm wide neoprene cells, change their electrical resistance for 5% at 100% strain. When the amount of eGaIn is increased, the cells are filled with eGaIn and the strain‐sensitivity of the electrical resistance rises to 300% at 100% strain. The developed conductors are patterned as stretchable on‐body coils for receiving magnetic signals in a clinical magnetic resonance imaging setup. First images with a stretchable coil are acquired on an orange and compared to the images that are recorded using a rigid copper coil of the same size. 相似文献
924.
Jonas Holmgren 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》1987,2(3)
This study describes rock reinforcement through the use of reinforced shotcrete in structural interaction with rock bolts. The intention of the investigation was to increase the knowledge of steel-fibre-reinforced shotcrete and the way in which bolt anchorage in shotcrete is designed. The researcher performed 22 large-scale laboratory tests on bolt-anchored, reinforced shotcrete lays, 19 of which were reinforced with Bekaert steel fibres, 2 with cold-tensioned reinforcement mesh, and 1 with an annealed mesh. Fibre content, fibre length and anchorage of the bolt in the shotcrete varied in the tests. For each large-scale test, adhesion tests on the rock-shotcrete interface were performed, as well as strength on sawn-out shotcrete cubes and beams both with and without fibres. The concrete mass was tested using cast cubes. Four large-scale tests on extremely thin fibre-reinforced linings without bolt anchorage also were performed. Two specimens contained steel fibres, and two contained glass fibres. Details also are provided of shear tests on split steel-fibre-reinforced test specimens on a small scale. The paper concludes with a discussion of the test results. 相似文献
925.
Jonas Feldheim David Wend Mara J. Lauer Camelia M. Monoranu Martin Glas Christoph Kleinschnitz Ralf-Ingo Ernestus Barbara M. Braunger Patrick Meybohm Carsten Hagemann Malgorzata Burek 《International journal of molecular sciences》2022,23(15)
Protocadherins (PCDHs) belong to the cadherin superfamily and represent the largest subgroup of calcium-dependent adhesion molecules. In the genome, most PCDHs are arranged in three clusters, α, β, and γ on chromosome 5q31. PCDHs are highly expressed in the central nervous system (CNS). Several PCDHs have tumor suppressor functions, but their individual role in primary brain tumors has not yet been elucidated. Here, we examined the mRNA expression of PCDHGC3, a member of the PCDHγ cluster, in non-cancerous brain tissue and in gliomas of different World Health Organization (WHO) grades and correlated it with the clinical data of the patients. We generated a PCDHGC3 knockout U343 cell line and examined its growth rate and migration in a wound healing assay. We showed that PCDHGC3 mRNA and protein were significantly overexpressed in glioma tissue compared to a non-cancerous brain specimen. This could be confirmed in glioma cell lines. High PCDHGC3 mRNA expression correlated with longer progression-free survival (PFS) in glioma patients. PCDHGC3 knockout in U343 resulted in a slower growth rate but a significantly faster migration rate in the wound healing assay and decreased the expression of several genes involved in WNT signaling. PCDHGC3 expression should therefore be further investigated as a PFS-marker in gliomas. However, more studies are needed to elucidate the molecular mechanisms underlying the PCDHGC3 effects. 相似文献
926.
Robert Nilsson Jeff Offutt Jonas Mellin 《Electronic Notes in Theoretical Computer Science》2006,164(4):97-114
Temporal correctness is crucial for real-time systems. Few methods exist to test temporal correctness and most methods used in practice are ad-hoc. A problem with testing real-time applications is the response-time dependency on the execution order of concurrent tasks. Execution order in turn depends on execution environment properties such as scheduling protocols, use of mutual exclusive resources as well as the point in time when stimuli is injected. Model based mutation testing has previously been proposed to determine the execution orders that need to be verified to increase confidence in timeliness. An effective way to automatically generate such test cases for dynamic real-time systems is still needed. This paper presents a method using heuristic-driven simulation to generate test cases. 相似文献
927.
Terror management theory suggests that people cope with awareness of death by investing in some kind of literal or symbolic immortality. Given the centrality of death transcendence beliefs in most religions, the authors hypothesized that religious beliefs play a protective role in managing terror of death. The authors report three studies suggesting that affirming intrinsic religiousness reduces both death-thought accessibility following mortality salience and the use of terror management defenses with regard to a secular belief system. Study 1 showed that after a naturally occurring reminder of mortality, people who scored high on intrinsic religiousness did not react with worldview defense, whereas people low on intrinsic religiousness did. Study 2 specified that intrinsic religious belief mitigated worldview defense only if participants had the opportunity to affirm their religious beliefs. Study 3 illustrated that affirmation of religious belief decreased death-thought accessibility following mortality salience only for those participants who scored high on the intrinsic religiousness scale. Taken as a whole, these results suggest that only those people who are intrinsically vested in their religion derive terror management benefits from religious beliefs. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
928.
The flow behavior of steels during deformation in the roll gap was simulated by means of single hit compression tests performed
in the temperature range 800 °C to 1200 °C. Strain rates of 0.2 to 50 s−1 were employed on selected low-carbon steels containing various combinations of niobium, boron, and copper. The stress/strain
curves determined at the higher strain rates were corrected for deformation heating so that constitutive equations pertaining
to idealized isothermal conditions could be formulated. When dynamic recovery is the only softening mechanism, these involve
a rate equation, consisting of a hyperbolic sine law, and an evolution equation with one internal variable, the latter being
the dislocation density. When dynamic recrystallization takes place, the incorporation of the fractional softening by dynamic
recrystallization in the evolution equation makes it possible to predict the flow stress after the peak. These expressions
can be employed in computer models for on-line gage control during hot-rolling. 相似文献
929.
The orientation relationships associated with different mechanisms of new grain formation during the hot deformation of a Mg–3.4% Al–0.33% Mn alloy were investigated using electron back-scattered diffraction (EBSD) techniques. Compression tests were carried out at 350 °C with a strain rate of 0.001 s?1 on samples machined from extruded tubes. Three types of microstructural features were produced at this temperature: (i) microbands (MBs); (ii) bulged regions; (iii) new grains formed by continuous dynamic recrystallization (cDRX). The formation of the MBs is attributed to the collection of basal dislocations in the MB boundaries. Both the bulges as well as the new cDRX grains are formed as a result of dislocation-based processes that produce c-axis rotations toward the loading axis (i.e. away from the radial direction–transverse direction (RD–TD) plane). Once nuclei have formed, however, the new grains have their c-axes located fairly close to the RD–TD plane. In this way dynamic recrystallization leads to the retention of the main characteristics of the initial RD–TD texture. 相似文献
930.
Verena Kräusel Alexander Fröhlich Martin Kroll Patrick Rochala Jonas Kimme Rafael Wertheim 《CIRP Annals》2018,67(1):5-8
A hybrid technology of inductive contact joining (ICJ) was developed to join fibre-reinforced thermoplastics (FRP) with metals by using a tool with single-sided heating. In comparison to conventional methods with separate heating, pressing and cooling, the unique new hybrid ICJ process is characterized by combining all three steps into one hybrid process. The maximum temperature is shifted toward the joining zone due to the direct cooling effect of the surface. FE simulations showed the temperature distributions within the joint. The performed experiments provided data for the temperature profile of the process and the resulting strength of the joint, type of damage and microstructural characteristics. Proven advantages include very short cycle time, competitive joint strength and limited influence on the mechanical properties of the metallic component. 相似文献