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One possibility of successfully dealing with the increasing heterogeneity of students is cooperative learning. However, this learning structure is still rarely used in physical education. To substantiate positive effects of cooperative learning in physical education and to support the commitment of pedagogical staff, the aim of this research was to evaluate physical, social, behavioral and psychological effects of interventions implementing cooperative learning structures in physical education lessons. The current systematic review was designed based on the PRISMA guidelines. Five databases were used to select articles that evaluated effects of cooperative learning in physical education of children and adolescents with an average age within the range of five to 19 years in August 2022. Studies had to report quantitative measured outcomes of cooperative learning. Two authors independently screened studies for eligibility and assessed risk of bias. Descriptive analyses were conducted to evaluate intervention effects. In total, 23 articles reporting 36 outcomes were included in the analysis with an overall sample size of 3699 children and adolescents aged between 6.5 and 17.5 years. Summarized 71% of all reported outcomes resulted in significant positive effects on cooperative learning compared to traditional teaching styles with most positive effects on social outcomes (92%). It is recommended to integrate different teaching styles, e.g. cooperative learning, to improve children’s development and to engage them in lifelong physical activity. Furthermore, interdisciplinary cooperation (e.g. between researchers and pedagogical school staff) should be sought in order to develop pedagogical approaches that consider the needs and prerequisites of students.

The recent development of double photoemission (DPE) spectroscopy at surfaces using laser-based high-order harmonic generation in combination with time-of-flight electron spectroscopy is reviewed. Relevant experimental conditions including the solid angle for collecting photoelectron pairs, the energy and angular resolutions, as well as the repetition rate and the photon energy range of light sources are introduced. As examples, we provide an overview of laser-based DPE results on the noble metals Ag and Cu as well as transition metal oxides NiO and CoO. The DPE energy and angular distributions of photoelectron pairs are compared with emphasis on the possible indications of electron-electron interaction. Potential further developments including femtosecond time-resolved DPE experiments are outlined.

The increasing demand for ultrahigh data storage densities requires development of 3D magnetic nanostructures. In this regard, focused electron beam induced deposition (FEBID) is a technique of choice for direct-writing of various complex nano-architectures. However, intrinsic properties of nanomagnets are often poorly known and can hardly be assessed by local optical probe techniques. Here, we demonstrate spatially resolved spin-wave spectroscopy of individual circular magnetic elements with radii down to 100 nm. The key component of the setup is a microwave antenna whose microsized central part is placed over a movable substrate with well-separated CoFe-FEBID nanodisks. The circular symmetry of the disks gives rise to standing spin-wave resonances and allows for the deduction of the saturation magnetization and the exchange stiffness of the material using an analytical theory. The presented approach is especially valuable for the characterization of direct-write elements opening new horizons for 3D nanomagnetism and magnonics., Comment: 10 pages, 5 figures

There is an increased attention on propositions on models, infrastructures and frameworks of IoT in both business reports and technical papers. These reports and publications frequently represent a juxtaposition of other related systems and technologies (e.g. Industrial Internet of Things, Cyber Physical Systems, Industry 4.0 etc). At present, the literature is missing a design process for integrating these constantly evolving systems and technologies in a clear and understandable step by step model. This paper contributes with a new reference architecture model for the integration of these systems and technologies. The reference architecture model is based on grouping of future and present techniques and presenting the design process through a new hierarchical framework and a new cascading model. With the application of the grounded theory, the hierarchical framework and the cascading model detail a new process for creating a taxonomy of categories and grouping of concepts into integration design. The new design process is tested and versified with an empirical review of Industry 4.0 frameworks and results with a new 5 levels reference architecture step by step model for the integration of these related systems and technologies (Industrial Internet of Things, Cyber Physical Systems, and Industry 4.0). We review 118 academic and industry papers published between 2010 and 2019. Then, we report the results of a qualitative empirical study that correlates academic literature with 14 world leading Industry 4.0 frameworks and initiatives. We therefore propose an architectural model that offers a better understanding of the systems integration between the Industrial Internet of Things and Industry 4.0.

This article is focused on the economic impact assessment of Internet of Things (IoT) and its associated cyber risks vectors and vertices - a reinterpretation of IoT verticals. We adapt to IoT both the Cyber Value at Risk model, a well-established model for measuring the maximum possible loss over a given time period, and the MicroMort model, a widely used model for predicting uncertainty through units of mortality risk. The resulting new IoT MicroMort for calculating IoT risk is tested and validated with real data from the BullGuard's IoT Scanner - over 310,000 scans - and the Garner report on IoT connected devices. Two calculations are developed, the current state of IoT cyber risk and the future forecasts of IoT cyber risk. Our work therefore advances the efforts of integrating cyber risk impact assessments and offer a better understanding of economic impact assessment for IoT cyber risk., http://doi.org/10.1016/J.COMPIND.2018.08.002

The coherent nonlinear dynamics of Abrikosov vortices in asymmetric pinning nanolandscapes is studied by theoretical modeling and combined microwave and dc electrical resistance measurements. The problem is considered on the basis of a single-vortex Langevin equation within the framework of a stochastic model of anisotropic pinning. When the distance over which Abrikosov vortices are driven during one half ac cycle coincides with one or a multiple of the nanostructure period, Shapiro steps appear in the current-voltage curves (CVCs) as a general feature of systems whose evolution in time can be described in terms of a particle moving in a periodic potential under combined dc and ac stimuli. While a dc voltage appears in response to the ac drive, the addition of a dc bias allows one to diminish the rectified voltage and eventually to change its sign when the extrinsic dc bias-induced asymmetry of the pinning potential starts to dominate the intrinsic one. This rectified negative voltage in the CVCs becomes apparent as \emph{zero-bias} Shapiro steps, which are theoretically predicted and experimentally observed for the first time., Comment: 7 pages, 6 figures

Partial methods play an important role in formal methods and beyond. Recently such methods were developed for parity games, where polynomial-time partial solvers decide the winners of a subset of nodes. We investigate here how effective polynomial-time partial solvers can be in principle by studying polynomial-time interactions of partial solvers. Concretely, we propose simple, generic composition patterns for partial solvers that preserve polynomialtime computability. We show that an implementation of this semantic framework manually discovers new partial solvers ��� including those that merge node sets that have the same but unknown winner ��� by studying games that composed partial solvers can neither solve nor simplify. We experimentally validate that this data-driven approach to refinement leads to polynomial-time partial solvers that can solve all standard benchmarks of structured games. For one of these polynomial-time partial solvers, we were unable to find even a sole random game that it won���t solve completely, although we generated a few billion random games of varying configurations to that end. However, the work presented here does not yet offer any deeper characterisations of which games are completely solved by such partial solvers.

It is well understood that solving parity games is equivalent, up to polynomial time, to model checking of the modal mu-calculus. It is a long-standing open problem whether solving parity games (or model checking modal mu-calculus formulas) can be done in polynomial time. A recent approach to studying this problem has been the design of partial solvers, algorithms that run in polynomial time and that may only solve parts of a parity game. Although it was shown that such partial solvers can completely solve many practical benchmarks, the design of such partial solvers was somewhat ad hoc, limiting a deeper understanding of the potential of that approach. We here mean to provide such robust foundations for deeper analysis through a new form of game, alternating reachability under parity. We prove the determinacy of these games and use this determinacy to define, for each player, a monotone fixed point over an ordered domain of height linear in the size of the parity game such that all nodes in its greatest fixed point are won by said player in the parity game. We show, through theoretical and experimental work, that such greatest fixed points and their computation leads to partial solvers that run in polynomial time. These partial solvers are based on established principles of static analysis and are more effective than partial solvers studied in extant work.

It is increasingly important to analyze system security quantitatively using concepts such as trust, reputation, cost, and risk. This requires a thorough understanding of how such concepts should interact so that we can validate the assessment of threats, the choice of adopted risk management, etc.. To this end, we propose a declarative language Peal+ in which the interaction of such concepts can be rigorously described and analyzed. Peal+ has been implemented in PEALT using the SMT solver Z3 as analysis back-end. PEALT's code generators target complex back-ends and evolve with optimizations or new back-ends. Thus we can neither trust the tool chain nor feasibly prove correctness of all involved artefacts. We eliminate the need to trust that tool chain by independently certifying scenarios found by back-ends in a manner agnostic of code generation and choice of back-end. This scenario validation is compositional, courtesy of Kleene's 3-valued logic and potential re nement of scenarios. We prove the correctness of this validation, discuss how PEALT presents scenarios to further users' understanding, and demonstrate the utility of this approach by showing how it can express attack-countermeasure trees so that the interaction of attack success probability, attack cost, and attack impact can be analyzed.

We study a new form of attractor in parity games and use it to define solvers that run in PTIME and are partial in that they do not solve all games completely. Technically, for color c this new attractor determines whether player c%2 can reach a set of nodes X of color c whilst avoiding any nodes of color less than c. Such an attractor is fatal if player c%2 can attract all nodes in X back to X in this manner. Our partial solvers detect fixed-points of nodes based on fatal attractors and correctly classify such nodes as won by player c%2. Experimental results show that our partial solvers completely solve benchmarks that were constructed to challenge existing full solvers. Our partial solvers also have encouraging run times. For one partial solver we prove that its runtime is in O(|V |3), that its output game is independent of the order in which attractors are computed, and that it solves all B��uchi games.

Increasingly, access to resources needs to be regulated or informed by considerations such as risk, cost, and reputation. We therefore propose a framework for policy languages, based on semi-rings, that aggregate quantitative evidence to support decision-making in access control systems. As aggregation operators \addition", \worst case", and \best case" over non- negative reals are both relevant in practice and amenable to analysis, we study an instance, Peal, of our framework in that setting. Peal is a stand-alone policy language but can also be integrated with existing policy languages. Peal policies can be synthesized into logical formulae that no longer make reference to quantities but capture all policy behavior. Satis ability checking of such formulae can be used to validate and analyze policies in this new evidence-based approach. We discuss a number of applications, including vacuity, redundancy, change-impact and safety analysis. The synthesis algorithm requires a form of subset enumeration, for which we develop bespoke algorithms and demonstrate experimentally that our algorithms work better than generic state exploration methods. We also sketch how our approach extends from non-negative reals to other semi-rings and even to rings such as the real numbers.

We present a tool that supports the understanding and validation of mechanisms that numerically aggregate trust evidence { which may stem from heterogenous sources such as geographical information, reputation, and threat levels. The tool is based on a policy com- position language Peal [3] and can declare Peal expressions and intended analyses of such expressions as input. The analyses include vacuity checking, sensitivity analysis of thresh- olds, and policy re nement. We develop and implement two methods for generating veri - cation conditions for analyses, using the SMT solver Z3 as backend. One method is explicit and space intense, the other one is symbolic and so linear in the analysis expressions. We experimentally investigate this space-time tradeo by observing the Z3 code generation and its running time on randomly generated analyses and on a non-random benchmark modeling majority voting. Our ndings suggest both methods have complementary value and may scale up su ciently for the analysis of most realistic case studies.

Access control to IT systems increasingly relies on the ability to compose policies. There is thus bene t in any framework for policy composition that is intuitive, formal (and so \an- alyzable" and \implementable"), expressive, independent of speci c application domains, and yet able to be extended to create domain-speci c instances. Here we develop such a framework based on Belnap logic. An access-control policy is interpreted as a four-valued predicate that maps access requests to either grant, deny, con ict, or unspeci ed { the four values of the Bel- nap bilattice. We de ne an expressive access-control policy language PBel, having composition operators based on the operators of Belnap logic. Natural orderings on policies are obtained by lifting the truth and information orderings of the Belnap bilattice. These orderings lead to a query language in which policy analyses, e.g. con ict freedom, can be speci ed. Policy analysis is supported through a reduction of the validity of policy queries to the validity of propositional formulas on predicates over access requests. We evaluate our approach through rewall policy and RBAC policy examples, and discuss domain-speci c and generic extensions of our policy language.

UHV-deposited films of the mixed phase of tetramethoxypyrene and tetracyanoquinodimethane (TMP1-TCNQ1) on gold have been studied using ultraviolet photoelectron spectroscopy (UPS), X-ray-diffraction (XRD), infrared (IR) spectroscopy and scanning tunnelling spectroscopy (STS). The formation of an intermolecular charge-transfer (CT) compound is evident from the appearance of new reflexes in XRD (d1= 0.894 nm, d2= 0.677 nm). A softening of the CN stretching vibration (red-shift by 7 cm-1) of TCNQ is visible in the IR spectra, being indicative of a CT of the order of 0.3e from TMP to TCNQ in the complex. Characteristic shifts of the electronic level positions occur in UPS and STS that are in reasonable agreement with the prediction of from DFT calculations (Gaussian03 with hybrid functional B3LYP). STS reveals a HOMO-LUMO gap of the CT complex of about 1.25 eV being much smaller than the gaps (>3.0 eV) of the pure moieties. The electron-injection and hole-injection barriers are 0.3 eV and 0.5 eV, respectively. Systematic differences in the positions of the HOMOs determined by UPS and STS are discussed in terms of the different information content of the two methods., 20 pages, 6 figures

We present p-automata, which accept an entire Markov chain as input. Acceptance is determined by solving a sequence of stochastic weak and weak games. The set of languages of Markov chains obtained in this way is closed under Boolean operations. Language emptiness and containment are equi-solvable, and languages themselves are closed under bisimulation. A Markov chain (respectively, PCTL formula) determines a p-automaton whose language is the bisimulation equivalence class of that Markov chain (respectively, the set of models of that formula). We define a simulation game between p-automata, decidable in EXPTIME. Simulation under-approximates language containment, whose decidability status is presently unknown.

Twenty years ago, modal and mixed specifications were proposed as abstract models of system behavior. In this paper, we explain the nature and utility of such specifications, relate them to other formalisms, showcase some of their established applications, and mention some existing tool support. We also present some recent complexity results for decision problems underlying such applications and list some remaining open problems.

This paper considers algorithms for counterexample generation for (bounded) probabilistic reachability properties in fully probabilistic systems. Finding the strongest evidence (i.e, the most probable path) violating a (bounded) until-formula is shown to be reducible to a single-source (hop-constrained) shortest path problem. Counterexamples of smallest size that are mostly deviating from the required probability bound can be computed by adopting (partially new hopconstrained) k shortest paths algorithms that dynamically determine k.

Automatically proving that (infinite-state) software programs satisfy a specification is an important task, but has proved very difficult. Thus, in order to obtain techniques that work with reasonable speed and without user guidance, researchers have typically targeted restricted classes of language features, programming idioms and properties. We have designed a system in which several of these specialised techniques can be used together in proving that a program is correct; this is done without breaking modularity by propagating information between the analyses, expressed as formulae of an expressive common logic. In this way, we can verify programs which, because they use diverse language features and idioms, are difficult or impossible to prove using any one individual technique. Our system is implemented in the experimental tool HECTOR.

Model checking is a particular approach to property verification of systems. One describes a system in a mathematical model, expresses the properties one wishes to verify for the system in a formal language, and then checks whether the model satisfies the formal property. Invented 25 years ago, this approach is fully automatic and has therefore gained wide acceptance and is increasingly being used in commercial research and development units. Impediments remain on the road to successful technology transfer. For one, the size of models often increases exponentially in the number of variables or sub-models, preventing scalable automation. Abstracting a model to reduce its size can be a cost-effective way of addressing this. For another, systems and models may be subject to change, e.g. in an incremental design process. One then seeks cost-effective means of ascertaining that property verifications remain to be valid as models evolve. This special section presents current research on such abstraction and change management of model checking. © Springer-Verlag 2007.

We propose a pattern for designing algorithms that run in polynomial time by construction and underapproximate the winning regions of both players in parity games. This approximation is achieved by the interaction of finitely many aspects governed by a common ranking function, where the choice of aspects and ranking function instantiates the design pattern. Each aspect attempts to improve the under-approximation of winning regions or decrease the rank function by simplifying the structure of the parity game. Our design pattern is incremental as aspects may operate on the residual game of yet undecided nodes. We present several aspects and one higher-order transformation of our algorithms���based on efficient, static analyses��� and illustrate the benefit of their interaction as well as their relative precision within pattern instantiations. Instantiations of our design pattern can be applied for local model checking and as pre-processors for algorithms whose worst-case running time is exponential.

We study consistency, satis��ability, and validity problems for collectively model checking a set of views endowed with labelled transi- tions, hybrid constraints on states, and atomic propositions. A PTIME algorithm for deciding whether a set of views has a common re��nement (consistency) is given. We prove that deciding whether a common re��ne- ment satis��es a formula of the hybrid mu-calculus (satis��ability), and its dual (validity), are EXPTIME-complete. We determine two generically generated \summary" views that constitute informative and consistent common re��nements and abstractions of a set of views (respectively).

The optical conductivity of the heavy fermions UPd2Al3 and UPt3 has been measured in the frequency range from 10 GHz to 1.2 THz (0.04 meV to 5 meV) at temperatures 1 K < T < 300 K. In both compounds a well pronounced pseudogap of less than a meV develops in the optical response at low temperatures; we relate this to the antiferromagnetic ordering. From the energy dependence of the effective electronic mass and scattering rate we derive the energies essential for the heavy quasiparticle. We find that the enhancement of the mass mainly occurs below the energy which is related to magnetic correlations between the local magnetic moments and the itinerant electrons. This implies that the magnetic order in these compounds is the pre-requisite to the formation of the heavy quasiparticle and eventually of superconductivity., RevTeX, 4 pages, 3 figures, email: dressel@pi1.physik.uni-stuttgart.de

The optical properties of the heavy-fermion compound UPd$_2$Al$_3$ have been measured in the frequency range from 0.04 meV to 5 meV (0.3 to 40 cm$^{-1}$) at temperatures $2 {\rm K}, Comment: RevTex, 15 pages, 7 figures

Using a priority preorder on requirements or specifications, we lift established property-verification techniques of threevalued model checking from single to multiple viewpoints. This lift guarantees a maximal degree of autonomy and accountability to single views, automatically synthesizes single-analysis results for multiple-view consistency and assertion checking, allows the re-use of single-view technology (e.g. standard model checkers), and transforms many meta-results (e.g. soundness of abstraction) from the singleview to the multiple-view setting. We formulate assertionconsistency lattices as a proper denotational universe for this lift, show that their symmetric versions are DeMorgan lattices, and classify both structures through (idempotent) order-isomorphisms on (self-dual) priority preorders in the finite case. In particular, this lift generalizes Fitting���s multiple-valued semantics of modal logic in that our treatment of negation generalizes Heyting negation beyond fully specified and consistent models. We compare our approach to existing work on multiple-valued model checking.

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Models in process algebra with abstract data types can be analysed by state space generation and reduction tools. The μCRL toolset implements a suite of distributed verification tools for clusters of workstations. We illustrate their application to large case studies from a wide range of application areas, such as functional analysis, scheduling, security analysis, test case generation and game solving.

Deregulation of intestinal immune responses seems to have a principal function in the pathogenesis of inflammatory bowel disease(1-4). The gut epithelium is critically involved in the maintenance of intestinal immune homeostasis-acting as a physical barrier separating luminal bacteria and immune cells, and also expressing antimicrobial peptides(3,5,6). However, the molecular mechanisms that control this function of gut epithelial cells are poorly understood. Here we show that the transcription factor NF kappa B, a master regulator of pro-inflammatory responses(7,8), functions in gut epithelial cells to control epithelial integrity and the interaction between the mucosal immune system and gut microflora. Intestinal epithelial-cell-specific inhibition of NF-kappa B through conditional ablation of NEMO ( also called I kappa B kinase-gamma ( IKK gamma)) or both IKK1 ( IKK alpha) and IKK2 ( IKK beta)-IKK subunits essential for NF-kappa B activation(7-9)-spontaneously caused severe chronic intestinal inflammation in mice. NF-kappa B deficiency led to apoptosis of colonic epithelial cells, impaired expression of antimicrobial peptides and translocation of bacteria into the mucosa. Concurrently, this epithelial defect triggered a chronic inflammatory response in the colon, initially dominated by innate immune cells but later also involving T lymphocytes. Deficiency of the gene encoding the adaptor protein MyD88 prevented the development of intestinal inflammation, demonstrating that Toll-like receptor activation by intestinal bacteria is essential for disease pathogenesis in this mouse model. Furthermore, NEMO deficiency sensitized epithelial cells to tumour-necrosis factor ( TNF)-induced apoptosis, whereas TNF receptor-1 inactivation inhibited intestinal inflammation, demonstrating that TNF receptor-1 signalling is crucial for disease induction. These findings demonstrate that a primary NF-kappa B signalling defect in intestinal epithelial cells disrupts immune homeostasis in the gastrointestinal tract, causing an inflammatory-bowel-disease-like phenotype. Our results identify NF-kappa B signalling in the gut epithelium as a critical regulator of epithelial integrity and intestinal immune homeostasis, and have important implications for understanding the mechanisms controlling the pathogenesis of human inflammatory bowel disease. RI van Loo, Geert/C-1505-2009; Becker, Christoph/A-6694-2008