Boolean Delay Equations: A simple way of looking at complex systems

Boolean Delay Equations (BDEs) are semi-discrete dynamical models with Boolean-valued variables that evolve in continuous time. Systems of BDEs can be classified into conservative or dissipative, in a manner that parallels the classification of ordinary or partial differential equations. Solutions to certain conservative BDEs exhibit growth of complexity in time. They represent therewith metaphors for biological evolution or human history. Dissipative BDEs are structurally stable and exhibit multiple equilibria and limit cycles, as well as more complex, fractal solution sets, such as Devil's staircases and ``fractal sunbursts``. All known solutions of dissipative BDEs have stationary variance. BDE systems of this type, both free and forced, have been used as highly idealized models of climate change on interannual, interdecadal and paleoclimatic time scales. BDEs are also being used as flexible, highly efficient models of colliding cascades in earthquake modeling and prediction, as well as in genetics. In this paper we review the theory of systems of BDEs and illustrate their applications to climatic and solid earth problems. The former have used small systems of BDEs, while the latter have used large networks of BDEs. We moreover introduce BDEs with an infinite number of variables distributed in space (``partial BDEs``) and discuss connections with other types of dynamical systems, including cellular automata and Boolean networks. This research-and-review paper concludes with a set of open questions.Comment: Latex, 67 pages with 15 eps figures. Revised version, in particular the discussion on partial BDEs is updated and enlarge

The intensity of competition after patent expiry in pharmaceuticals. A cross-country analysis

This paper shows that the relationships between the dynamics of drug priees, patent expiry, and competition by multisource drugs vary significantly across countries. A clear distinction seems to emerge. On the one side, systems that rely on market based competition (particularly the US) promote a clear distinction between firms that act as innovators and firms that act as imitators after patent expiry. Original products enjoy premium prices under patent protection, and face fierce price competition after patent expiry. On the contrary, systems that rely on administered prices (particularly France and Italy) nurture strategies of pre-emptive brand proliferation and horizontal differentiation by imitative brand name products, well before patent expiry. Our work confirms that that systems that rely on administered prices have tended to stifle price competition, to protect less efficient companies, and to encourage strategies of incremental innovation and imitation

Advanced methods for safe visualization on automotive displays

Camera Monitor Systems (CMSs), for example, for backup cameras or mirror replacements, become increasingly important and already cover safety aspects such as guaranteed latency and no frame freeze. Today\u27s approaches deal only with supervision of the digital interface, LCD backlight, and power supply. This paper introduces methods for advanced safety monitoring of panel electronics and optical display output that aim to enable future CMS based automotive use cases. Our methods are based on correlation of physical measurements with predicted values derived from a corresponding display model. This model was made via calibration measurements and many test patterns. Correlation of the monitoring results with predicted values corresponds to the probability that the RGB data are shown as intended. This implies that an overlying system, an Automotive Safety Integrity Level (ASIL) Prepared Video Safety System (APVSS), ensures that only safety verified RGB data are provided to the panel electronics. In case of failures, our methods enable a safe system state, for example, by deactivating the panel. An additional challenge is to allow graceful degradations, a safe but slightly degraded image may provide a better customer experience compared with no information. We successfully verified our approach by a fully functional prototype and extensive evaluation towards “light-to-light” (camera to display output) supervision

Do you really know your consumers? : analyzing the impact of consumer knowledge on use and failure evaluation of consumer electronics

The field of Consumer Electronics (CE) can be characterized by continuous technological innovation, fierce global competition, strong pressure on time-to-market, fast adoption cycles and increasingly complex business processes. In this context it is increasingly challenging for product designers and developers to provide products with unique features and excellent price / performance characteristics, as well as having to provide products that meet all the consumer’s expectations. From a business perspective, research has shown that the number of consumer complaints and even product returns is increasing for complex CE (Den Ouden, 2006). Further research on the causes of these complaints showed that almost half of the complaints were due to non-technical reasons. Therefore, more insight is needed into product quality and reliability from a consumer point of view. A literature review showed that quality and reliability methods that are currently used in product development insufficiently prevent the large variety of consumer complaints: the number of consumer complaints is rising while at the same time the root cause of these complaints is more difficult to retrace. Product failures need to be measured and analyzed from a consumer’s point of view since the traditional fault-complaint propagation model fails to capture all potential sources of consumer complaints. More insight is needed into the relation between the diversity of consumers and the propagation of product development faults to these "Consumer-Perceived Failures" (CPFs).A conceptual framework was developed to model the underlying factors related to the propagation of product development faults to consumer complaints from a consumer point of view. This framework is based on insights from human-computer interaction and consumer behavior literature and the results of an explorative experiment. Furthermore, the most commonly used consumer selection criteria for consumer tests based on demographics and/or product adoption related characteristics do not sufficiently cover differences in CPFs. The consumer characteristic "consumer knowledge" is hypothesized to have a strong impact on differences in the underlying variables of this framework. A review of relevant consumer models and consumer characteristics used in human-computer interaction and consumer behavior research shows that this construct relates to cognitive structures consumers have about a product’s functioning as well as cognitive processes needed to use a complex CE product. This dissertation therefore aimed to investigate the hypothesized effect of consumer knowledge on two important variables of the conceptual framework: product usage behavior and failure attribution. By using multiple surveys, two laboratory experiments and a web-based experiment, the following aspects of the conceptual framework were investigated in this dissertation: • How and to what extent consumers can be differentiated on knowledge of complex CE • The effect of consumer knowledge on differences in product usage behavior • The effect of consumer knowledge on differences in attribution of product failures The results of the surveys to differentiate consumers on knowledge (both core and supplemental domains) of innovative LCD televisions demonstrated the successful development and validation of measurements of both subjective and objective measurements of expertise and familiarity. It was concluded that the selection of consumer knowledge constructs as criterion for differentiating consumers for a consumer test depends on the target consumer group for a product (e.g. a very narrow homogeneous consumer group versus mass consumer markets), the type of product (e.g. passive versus active interaction) and the goal of the consumer test. The laboratory experiment which investigated the effect of subjective expertise and objective familiarity on product usage behavior showed that higher levels of subjective expertise on both the television and computer domain result in significantly better effectiveness and efficiency and less interaction problems when performing complex product related tasks. Next, the results also showed that differences in subjective expertise stronger relate to differences in product usage behavior than those in objective familiarity. The findings of this study help product developers and designers to better understand differences in product usage behavior when consumers encounter interaction problems and can therefore help the product designers and developers to take better design decisions.The results of both failure attribution experiments with simulated failure scenarios of picture quality failures in an LCD television showed that only objective expertise differences affect differences in consumer perception of product failures. However, although the failure attribution of consumers with higher levels of objective expertise has more dimensions and is more refined, higher levels of objective expertise on a product do not automatically result in attributions that are more in accordance with the real physical cause of the failure. This has important implications because currently used test methods often differentiate consumers only on previous experience (i.e. familiarity) with a product. The results of both studies also demonstrated that both failure cause and failure impact do not significantly affect how consumers attribute the failures. In total it can be concluded that, when evaluating the effect of consumer diversity on fault-complaint propagation, consumer knowledge can be used to differentiate product use and failure attribution for complex CE. However, it should be noted that especially for failure attribution this effect is not consistent across different types of failures. In addition, compared to objective and subjective familiarity and subjective expertise, objective expertise has the strongest impact. In the context of fast evolving complex CE, objective expertise measurements are becoming increasingly important because familiarity or subjective expertise measurements on the (technical) functioning of currently available products can quickly become "incorrect" or "incomplete" for the next generation of products. These insights can support product designers and developers to make the right design decisions to enhance consumer satisfaction

Regarding Pilot Usage of Display Technologies for Improving Awareness of Aircraft System States

ed systems and the procedures for ng in complexity. This interacting trend places a larger burden on pilots to manage increasing amounts of information and to understand system interactions. The result is an increase in the likelihood of loss of airplane state awareness (ASA). One way to gain more insight into this issue is through experimentation using objective measures of visual behavior. This study summarizes an analysis of oculometer data obtained during a high-fidelity flight simulation study that included a variety of complex pilot-system interactions that occur in current flight decks, as well as several planned for the next generation air transportation system. The study was comprised of various scenarios designed to induce low and high energy aircraft states coupled with other emulated causal factors in recent accidents. Three different display technologies were evaluated in this recent pilot-in-the-loop study conducted at NASA Langley Research Center. These technologies include a stall recovery guidance algorithm and display concept, an enhanced airspeed control indication of when the automation is no longer actively controlling airspeed, and enhanced synoptic diagrams with corresponding simplified electronic interactive checklists. Multiple data analyses were performed to understand how the 26 participating airline pilots were observing ASA-related information provided during different stag specific events within these stages

Behavioral and electrophysiological correlates of cognitive control in ex-obese adults

Impaired cognitive control functions have been documented in obesity. It remains unclear whether these functions normalize after weight reduction. We compared ex-obese individuals, who successfully underwent substantial weight loss after bariatric surgery, to normal weight participants on measures of resistance to interference, cognitive flexibility and response inhibition, obtained from the completion of two Stroop tasks, a Switching task and a Go/NoGo task, respectively. To elucidate the underlying brain mechanisms, event-related potentials (ERPs) in the latter two tasks were examined. As compared to controls, patients were more susceptible to the predominant but task-irrelevant stimulus dimension (i.e., they showed a larger verbal Stroop effect), and were slower in responding on trials requiring a task-set change rather than a task-set repetition (i.e., they showed a larger switch cost). The ERP correlates revealed altered anticipatory control mechanisms (switch positivity) and an exaggerated conflict monitoring response (N2). The results suggest that cognitive control is critical even in ex-obese individuals and should be monitored to promote weight loss maintenance

FSA field test

The 12 continental remote sites were decommissioned. Testing was consolidated into a five-site network consisting of the four Southern California sites and a new Florida site. 16 kW of new state-of-the-art modules were deployed at the five sites. Testing of the old modules continued at the Goldstone site but as a low-priority item. Array testing of modules is considered. Additional new testing capabilities were added. A battery-powered array data logger is discussed. A final set of failure and degradation data was obtained from the modules

State of Alaska Election Security Project Phase 2 Report

A laska’s election system is among the most secure in the country, and it has a number of safeguards other states are now adopting. But the technology Alaska uses to record and count votes could be improved— and the state’s huge size, limited road system, and scattered communities also create special challenges for insuring the integrity of the vote. In this second phase of an ongoing study of Alaska’s election security, we recommend ways of strengthening the system—not only the technology but also the election procedures. The lieutenant governor and the Division of Elections asked the University of Alaska Anchorage to do this evaluation, which began in September 2007.Lieutenant Governor Sean Parnell. State of Alaska Division of Elections.List of Appendices / Glossary / Study Team / Acknowledgments / Introduction / Summary of Recommendations / Part 1 Defense in Depth / Part 2 Fortification of Systems / Part 3 Confidence in Outcomes / Conclusions / Proposed Statement of Work for Phase 3: Implementation / Reference

Preliminary Candidate Advanced Avionics System (PCAAS)

Specifications which define the system functional requirements, the subsystem and interface needs, and other requirements such as maintainability, modularity, and reliability are summarized. A design definition of all required avionics functions and a system risk analysis are presented

Development of preliminary design concept for multifunction display and control system for Orbiter crew station. Task 3: Concept analysis

The access schema developed to access both individual switch functions as well as automated or semiautomated procedures for the orbital maneuvering system and electrical power and distribution and control system discussed and the operation of the system is described. Feasibility tests and analyses used to define display parameters and to select applicable hardware choices for use in such a system are presented and the results are discussed