Morphology and mechanical properties of poly(propylene)/polystyrene blends compatibilized with polystyrene-block-poly(ethylene-co-propylene)

Compatibilizing effects of diblock copolymer polystyrene-block-poly(ethylene-co-propylene) (SEP) on the morphology and mechanical properties of immiscible blends of poly(propylene) (PP) and polystyrene (PS) were investigated. Notched impact strength, yield stress, elongation at yield and Young's modulus were determined as a function of different weight ratios of PP and PS and different amounts of added SEP as well. Scanning electron microscopy revealed a two-phase morphology of PP/PS blends, which exhibit poor mechanical properties. Even 2,5 wt.-% of SEP added to PP/PS blends can improve the notched impact strength and elongation at yield compared to non-compatibilized PP/PS blends. 10 wt.-% of SEP compatibilizer converted the brittle PP/PS blend to quite impactresistant polymeric material. Mechanical properties were improved because of the morphological changes and increased interfacial adhesion as a result of SEP localization between PP and PS phases. An analysis of yield stress data in terms of theoretical models showed that yield stress values of binary PP/PS blends can be predicted with Nielsen's model.     

Conceptualization,measurement, and application of semantic transparency in visual notations

Numerous visual notations are present in technical and business domains. Notations have to be cognitively effective to ease the planning, documentation, and communication of the domains’ concepts. Semantic transparency (ST) is one of the elementary principles that influence notations’ cognitive effectiveness. However, the principle is criticized for not being well defined and challenges arise in the evaluations and applications of ST. Accordingly, this research’s objectives were to answer how the ST principle is defined, operationalized, and evaluated in present notations as well as applied in the design of new notations in ICT and related areas. To meet these objectives, a systematic literature review was conducted with 94 studies passing the selection process criteria. The results reject one of the three aspects, which define semantic transparency, namely “ST is achieved with the use of icons.” Besides, taxonomies of related concepts and research methods, evaluation metrics, and other findings from this study can help to conduct verifiable ST-related experiments and applications, consequently improving the visual vocabularies of notations and effectiveness of the resulting diagrams.

     

Exploring multi-user interactions with dynamic NFC-displays

Near Field Communication (NFC) is an emerging technology for touch-based mobile interactions with single- and multi-tagged objects. Although the latter may allow for simultaneous and collaborative interactions, most prototypes were not designed for multiple users and were only evaluated with single-user interactions. In this paper, we investigate the design, usability and user experience of multi-user interactions on dynamic NFC-displays. These interactive surfaces use a grid of NFC-tags for the direct manipulation of projected application user interfaces. In two user studies with three prototypes for multi-user interaction, we evaluated the performance of dynamic NFC-displays, interactions among users and the interplay between mobile devices and large displays.     

Flow-sensitive, context-sensitive, and object-sensitive information flow control based on program dependence graphs

Information flow control (IFC) checks whether a program can leak secret data to public ports, or whether critical computations can be influenced from outside. But many IFC analyses are imprecise, as they are flow-insensitive, context-insensitive, or object-insensitive; resulting in false alarms. We argue that IFC must better exploit modern program analysis technology, and present an approach based on program dependence graphs (PDG). PDGs have been developed over the last 20 years as a standard device to represent information flow in a program, and today can handle realistic programs. In particular, our dependence graph generator for full Java bytecode is used as the basis for an IFC implementation which is more precise and needs less annotations than traditional approaches. We explain PDGs for sequential and multi-threaded programs, and explain precision gains due to flow-, context-, and object-sensitivity. We then augment PDGs with a lattice of security levels and introduce the flow equations for IFC. We describe algorithms for flow computation in detail and prove their correctness. We then extend flow equations to handle declassification, and prove that our algorithm respects monotonicity of release. Finally, examples demonstrate that our implementation can check realistic sequential programs in full Java bytecode.     

The process map as an instrument to standardize processes: design and application at a financial service provider

The standardization of processes and the identification of shared business services in a service-oriented architecture (SOA) are currently widely discussed. Above all in practice, however, there still is a lack of appropriate instruments to support these tasks. In this paper an approach for a process map is introduced which allows for a systematic presentation—as complete as possible—of the processes in an enterprise (division). After a consistent refinement of the process has taken place by means of aggregation/disaggregation respectively, generalization/specialization relations, it is possible to identify primarily functional similarities of the detailed sub-processes. The application of the process map at a financial service provider (FSP) highlights how these similarities can be taken as a basis to standardize processes and to identify shared services.     

Utilizing Iron's Attractive Chemical and Magnetic Properties in Microrocket Design,Extended Motion,and Unique Performance

All‐in‐one material for microrocket propulsion featuring acid‐based bubble generation and magnetic guidance is presented. Electrochemically deposited iron serves as both a propellant, toward highly efficient self‐propulsion in acidic environments, and as a magnetic component enabling complete motion control. The new microrockets display longer lifetime and higher propulsion efficiency compared to previously reported active metal zinc‐based microrockets due to the chemical properties of iron and the unique structure of the microrockets. These iron‐based microrockets also demonstrate unique and attractive cargo towing and autonomous release capabilities. The latter is realized upon loss of the magnetic properties due to acid‐driven iron dissolution. More interestingly, these bubble‐propelled microrockets assemble via magnetic interactions into a variety of complex configurations and train structures, which enrich the behavior of micromachines. Modeling of the magnetic forces during the microrocket assembly and cargo capture confirms these unique experimentally observed assembly and cargo‐towing behaviors. These findings provide a new concept of blending propellant and magnetic components into one, toward simplifying the design and fabrication of artificial micro/nanomachines, realizing new functions and capabilities for a variety of future applications.     

User-Sensitive Inclusive Design

Although “User-Centred”, “Participatory”, and other similar design approaches have proved to be very valuable for mainstream design, their principles are more difficult to apply successfully when the user group contains, or is composed of, older and/or disabled users. In the field of design for older and disabled people, the “Universal Design”, “Inclusive Design” and “Design for All” movements have encouraged designers to extend their design briefs to include older and disabled people. The downside of these approaches is that they can tend to encourage designers to follow a traditional design path to produce a prototype design, and only then investigate how to modify their interfaces and systems to cope with older and/or disabled users. This can lead to an inefficient design process and sometimes an inappropriate design, which may be “accessible” to people with disabilities, but in practice unusable. This paper reviews the concept that the authors have called “User-Sensitive Inclusive Design”, which suggests a different approach to designing for marginalised groups of people. Rather than suggesting that designers rely on standards and guidelines, it is suggested that designers need to develop a real empathy with their user groups. A number of ways to achieve this are recommended, including the use of ethnography and techniques derived from professional theatre both for requirements gathering and for improving designers’ empathy for marginalised groups of users, such as older and disabled people.     

Service integrators in business networks—the importance of relationship values

To realise the potentials of CRM (customer relationship management), relationship-specific processes need to be designed and implemented in companies. This is all the more important and complicated in business networks where two or more actors collaborate to serve the customers. A good collaboration within business networks is the basis for understanding the customer process and identifying customer needs. But, even in these days of customer orientation, transaction orientation is still a matter of strong interest, and the following questions remain to be answered: What is the difference between relationship-oriented processes and transaction-oriented processes, and how can relationship-oriented processes be designed for a business network? The authors give first answers to both questions by using a systematic, goal-oriented specialisation of generic actions. To give an example, one relationship-oriented process will be designed and specified for a certain customer process in the course of this paper.     

Temporal kernel CCA and its application in multimodal neuronal data analysis

Data recorded from multiple sources sometimes exhibit non-instantaneous couplings. For simple data sets, cross-correlograms may reveal the coupling dynamics. But when dealing with high-dimensional multivariate data there is no such measure as the cross-correlogram. We propose a simple algorithm based on Kernel Canonical Correlation Analysis (kCCA) that computes a multivariate temporal filter which links one data modality to another one. The filters can be used to compute a multivariate extension of the cross-correlogram, the canonical correlogram, between data sources that have different dimensionalities and temporal resolutions. The canonical correlogram reflects the coupling dynamics between the two sources. The temporal filter reveals which features in the data give rise to these couplings and when they do so. We present results from simulations and neuroscientific experiments showing that tkCCA yields easily interpretable temporal filters and correlograms. In the experiments, we simultaneously performed electrode recordings and functional magnetic resonance imaging (fMRI) in primary visual cortex of the non-human primate. While electrode recordings reflect brain activity directly, fMRI provides only an indirect view of neural activity via the Blood Oxygen Level Dependent (BOLD) response. Thus it is crucial for our understanding and the interpretation of fMRI signals in general to relate them to direct measures of neural activity acquired with electrodes. The results computed by tkCCA confirm recent models of the hemodynamic response to neural activity and allow for a more detailed analysis of neurovascular coupling dynamics.     

Influence of a chip scale package on the frequency response of a MEMS microphone

This paper describes the influence of a chip scale MEMS package (CSMP) on the acoustic behaviour of a silicon microphone. The influence was calculated using an electro-mechanical–acoustical equivalent circuit. Standard packaging of microphones using die bonding and wire bonding leads to a large front volume which acts as a Helmholtz resonator. This can dramatically influence the frequency response of the microphone system by adding a second resonance. In the worst case this second resonance is in the acoustic frequency range, thus degrading its performance in an unacceptable way. In case of the CSMP only a small front volume is generated between the substrate and the flip-chipped microphone chip. Thus the resonance step-up is very small compared to standard packages. Furthermore the frequency response can be flattened by optimizing the geometry of the small sound holes in the substrate. By choosing an appropriate geometry of these sound holes the package can act as a low pass filter where the cut-off frequency can be placed to the desired value of the acoustic spectrum.