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The low viscosity of asphalt concrete at T Ͼ 135°C is necessary for the construction and compaction process of high-quality asphalt concrete layers. Whereas the continuous increase of viscosity with decreasing temperature is desirable for the reduction of permanent deformations during warm periods, so-called top-down cracking may occur in the course of temperature drops during cold periods. In order to explain the complex viscoelastic properties of asphalt concrete, a multiscale model is proposed. Hereby, the viscoelastic behavior of bitumen serves as input and the effect of air voids and aggregates is investigated. The viscous properties of bitumen are identified, using the bending-beam rheometer and the dynamic-shear rheometer, providing access to the viscoelastic material response for different temperature and loading regimes. With the rheological properties of bitumen at hand, the viscoelastic properties of mastic, mortar, and asphalt concrete are determined using continuum micromechanics, employing the elastic-viscoelastic "correspondence principle." The creep properties of asphalt concrete obtained from the presented mode of upscaling from the bitumen to the asphalt scale is validated by means of cyclic tests and static uniaxial creep tests.

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Inter-organizational systems form the basis for successful business collaboration in the Internet and B2B e-commerce era. To properly design and manage such systems one needs to understand the structure and dynamics of the relationships between organizations. The evaluation of such inter-organizational relationships (IORs) is normally conducted using ''success factors''. These are often referred to as constructs, such as trust and information sharing. In strategic management and performance analysis, different methods are employed for evaluating business performance and strategies, such as the Balanced Scorecard (BSC) method. The BSC utilizes success factors for measuring and monitoring IORs against business strategies. For these reasons, a thorough understanding of success factors, the relationships between them, as well as their relationship to business strategies is required. In other words, understanding success factors allows strategists deriving measurements for success factors as well as aligning these success factors with business strategies. This underpins nowadays close relationship between business strategy, IORs and their realization by means of inter-organizational systems. In this paper, we present (1) a systematic literature review studying success factors and their impact on IORs as well as (2) an analysis of the results found. The review is based on 177 publications, published between 2000 and 2012, dealing with factors influencing IORs. The work presented provides an overview on success factors, Electronic supplementary material The online version of this article (influencing relationships between success factors, as well as their influence on the success of IORs. The work is somehow ''meta-empirical'' as it only looks at published studies and not on own cases. Consequently, it is based on the assumption that studies in scientific literature represent the real-world. The constructs and relationships found in the review are grouped based on their scope and summarized in a cause and effect model. The grouping of constructs results in five groups including Relationship Orientation, Relational Norm, Relational Capital, Atmosphere, and Others. Since the cause and effect model represents a directed graph, different network analysis methods may be applied for analyzing the model. In particular, an in-and out-degree analysis is applied on the cause and effect model for detecting the most influencing as well as the most influenced success factors.