Miracle-dz/UniFAR-FTUs huggingface dataset:
Entropy Bounds in R×S3 Geometries

Abstract Exact calculations are given for the Casimir energy for various fields in R × S 3 geometry. The Green's function method naturally gives a result in a form convenient in the high-temperature limit, while the statistical–mechanical approach gives a form convenient for low temperatures. The equivalence of these two representations is demonstrated. Some discrepancies with previous work are noted. In no case, even for N =4 SUSY, is the ratio of entropy to energy found to be bounded. This deviation, however, occurs for low temperature, where the equilibrium approach may not be relevant. The same methods are used to calculate the energy and free energy for the transverse electric modes in a half-Einstein universe bounded by a perfectly conducting 2-sphere.
Design and Simulations of Wheel-Legged Mobile Robot

The problems of determining dynamic and kinematic parameters of wheel)legged mobile robot were considered in the paper. The numerical computer model of robot was worked out and simulation researches of suspension were completed. The motion of wheel on road with obstacles and walking motion of wheel were analyzed for determining kinematic and dynamic parameters.
Front-line Employee versus Customer Perceptions of Quality Attributes

In order to improve the quality of service co-production, both academics and managers have pointed out the pivotal role of front-line employees (FLEs) in improving the service experience. Few studies, however, have simultaneously examined the quality perceptions of each group. Do FLEs perceive service quality in the same way as their customers? If this is the case, service quality itself will tend to improve. The authors carried out a comparative quantitative survey in a banking services context where financial advisors and customers were asked to answer the same set of questions about customer perceptions of service quality. FLEs were asked to answer the survey as if they were customers. The research results show significant perception mismatches between customers and FLEs. Financial advisors fail to accurately identify service quality attributes that are important for their customers. The authors' findings provide evidence that quality management processes should take into account perception-based quality gaps. The article also discusses the most important reasons and negative consequences of perception mismatches and proposes ways to overcome them.
A Study of Hinge-Transmit Property of BGP Routing System

From the aspect of inter-domain routing security, it is important to identify the critical ASes which transmit a large fraction of data traffic. By analyzing the BGP routing process under the control of routing polices and evaluating a series of Transmit factors, we realize that BGP routing system has a Hinge-Transmit property. It indicates that Tier-1 AS set is the hinge of the Internet, transmitting a large fraction of data traffic to the whole network; a subset of Tier-1 AS set with a special topological location (core AS set) is the hinge of data delivery paths to a specified destination, transmitting a large fraction of data traffic from any source to the destination. These hinge ASes are the keys of Internet security and should be protected carefully. Finally, we verify the result by Route Views routing tables.
Simulation of carrier and power losses in semiconductor disk lasers

We present the self-consistent numerical model for simulation of multi-mode operation of optically pumped semiconductor disk lasers. We use this model to analyze carrier and power losses in GaN-, GaAs- and GaSb-based structures operating at 0.4, 1.3 and 2.8 μm, respectively.
Poverty dynamics in Spain: a study of transitions in the 1990s

Even if individuals care about their current economic status, they are mainly concerned about the time they remain in it (its duration). The expected duration of an economic status affects how individuals perceive it and therefore, it should modify any economic policy aiming for Social Welfare maximisation. Poverty is defined as a state of economic hardship for individuals or households and therefore, the study of transitions into or out of this status and its duration and persistence bring about further information on the causes of poverty and the ways to exit from it or avoid it. Using longitudinal data on Spanish households, some groups of households are detected as long slayers in poverty after some time in it and other are found as only transitional poor. Some evidence is also found in the data of the duration dependence of the probability of entering or exiting poverty. Moreover, some groups of households reveal a distinct shape of the probability of entering or exiting poverty in time. The group of female headed households and households without a spouse appears to be that having most difficulty in exiting poverty in the short-run. In turn, it is those households headed by an unemployed or part-time employed individual who are more likely to fall into poverty. The main reason pushing a household into or out of poverty seems to be the employment/unemployment and viceversa transition of the head of household. However, changes in the demographic characteristics of the household appear to significantly affect the probability of re-entering poverty for the most mobile group of households.
Phase Based and Application Based Dynamic Encoding Scheme for Multi-level Cell STT-RAM

The emerging Spin Torque Transfer memory (STT-RAM) appeared to be a promising candidate for future on-chip caches because of its high storage density, zero leakage power consumption, long endurance, high access speed etc. However, before the STT-RAM can be deployed in on-chip caches, there is one critical issue that has to be solved: the high write current of STT-RAM, which results in high dynamic power consumption. Each cell of multi-level cell STT-RAM (MLC STT-RAM) has four resistance states which can present the four 2-bit logical value pairs (00, 01, 10 and 11). We find that the proportion of the 2-bit logical value pairs written to L2 Cache changes with time and applications. Since the four resistance states have different write energies, we therefore propose schemes to map the four resistance states to the four 2-bit logical value pairs dynamically according to their proportions. The resistance state which has lower write energy can represent the 2-bit logical value pair which appears more frequently. In this paper, we propose phase based dynamic encoding policy (PBDE) and application based dynamic encoding policy (ABDE). The PBDE divides an entire process into many phases, and each phase chooses its best encoding policy to minimize power consumption. The ABDE chooses the best encoding scheme for cache blocks according to application types. Our evaluations show that PBDE and ABDE can achieve 2.7% and 4.5% write energy reduction over STT-RAM based caches respectively.
A Sliding-window Based Adaptive Approximating Method to Discover Recent Frequent Itemsets from Data Streams

— Frequent-patterns discovery in data streams is an active research area and more challenging than traditional database mining since several additional requirements need to be satisfied. In this paper, we propose a mining algorithm for finding frequent itemsets over sliding windows in a data stream. Different from most existing algorithms, our method is based on the theory of Combinatorial Approximation to approximate the counts of itemsets from some summary information of the stream. We also devise the novel concept of fair-cutter, which results in an original technique called dynamically approximating and makes our method capable of approximating adaptively for different itemsets. Empirical results show that the proposed method is quite efficient and scalable; moreover, the mining result from approximations achieves high accuracy.
Independent spontaneous mitochondrial malate dehydrogenase null mutants in soybean are the result of deletions.

The mitochondrial malate dehydrogenase-1 (Mdh1) gene of soybean [Glycine max (L.) Merr. ] spontaneously mutates to a null phenotype at a relatively high rate. To determine the molecular basis for the instability of the Mdh1 gene, the gene was cloned and sequenced. The null phenotype correlated with the deletion of specific genomic restriction fragments that encode the Mdh1 gene. The composition of the Mdh1 gene and its environs were compared with those of the more stable MDH2 gene. Several possible causes of the observed instability were found, including duplications, repeats, and two regions with similarity to a soybean catalase. The most likely cause of instability, however, appeared to be a 1233 bp region with 58.9% identity to the Cyclops retrotransposons. Translation of a 714 bp segment of this region produced a peptide composed of 238 amino acid residues that showed 35-40% identity and 55-60% similarity to several putative Cyclops gag-pol proteins (group-specific antigen polyprotein). This short peptide also contained a segment that corresponded to the protease active site of the gag-pol protein. Thus in an appropriate genetic background, a retrotransposon, whether whole or fractured, could promote genetic rearrangements.
Metabolic aspects of bacterial persisters

Persister cells form a multi-drug tolerant subpopulation within an isogenic culture of bacteria that are genetically susceptible to antibiotics. Studies with different Gram negative and Gram positive bacteria have identified a large number of genes associated with the persister state. In contrast, the revelation of persister metabolism has only been addressed recently. We here summarize metabolic aspects of persisters, which includes an overview about the bifunctional role of selected carbohydrates as both triggers for the exit from the drug tolerant state and metabolites which persisters feed on. Also alarmones as indicators for starvation have been shown to influence persister levels via different signaling cascades involving the activation of toxin-antitoxin systems and other regulatory factors. Finally, recent data obtained by 13C-isotopolog profiling demonstrated an active amino acid anabolism in Staphylococcus aureus cultures challenged with high drug concentrations. Understanding the metabolism of persister cells poses challenges but also paves the way for the development of anti-persister compounds.
GPU Image Inpainting via Texture Synthesis

Image inpainting refers to the process of changing an image so that an observer seeing the change would not guess that the image was intended to look any other way. It usually refers to the task of restoring damaged images and is considered an art for the careful artist’s eye it takes to get all the details right. This work implements an algorithm for automatically inpainting a user-specified region while taking advantage of the parallelism available in recent programmable graphcis hardware. To replicate high frequency detail, the method uses texture synthesis techniques for overwriting “bad” data.
Using network data to improve digital investigation in cloud computing environments

With the rise of cloud computing environments and the increasingly ubiquitous utilization of its opportunities, the amount of data analysed in a traditional digital forensic examination is increasing significantly, thus increasing the risk to miss evidence. Without adopting new methodology or different approaches investigators are unable to guarantee a valid digital forensic investigation. Due to the large amount of cloud platforms it is hardly feasible to identify them when investigating a computer. Knowing all different services of cloud computing platforms is impossible for a human. The paper therefore proposes to investigate raw network data in order to improve the complete digital investigation process by correlating network and computer forensic parts. We present a new method to analyse network traffic to find information about the usage of cloud specific data. With the possibility to automate this extraction and the comparison with a cloud service knowledge base, the error rate of a forensic investigation is reduced. It also reduces the risk of human errors.
Bees and Firefly Algorithms for Noisy Non-Linear Optimisation Problems

— Effective methods for solving the complex and noisy engineering problems using a finite sequence of instructions can be categorised into optimisation and meta-heuristics algorithms. The latter might be defined as an iterative search process that efficiently performs the exploration and exploitation in the solution space aiming to efficiently find near optimal solutions. Various natural intelligences and inspirations have been adopted into the iterative process. In this work, two types of meta-heuristics called Bees and Firefly algorithms were adapted to find optimal solutions of noisy non-linear continuous mathematical models. Considering the solution space in a specified region, some models contain global optimum and multiple local optimums. Bees algorithm is an optimisation algorithm inspired by the natural foraging behaviour of honey bees. Firefly algorithm is used to produce a near optimal solution under a consideration of the flashing characteristics of fireflies. A series of computational experiments using each algorithm were conducted. Experimental results were analysed in terms of best solutions found so far, mean and standard deviation on both the actual yields and execution time to converge to the optimum. The Firefly algorithm seems to be better when the noise levels increase. The Bees algorithm provides the better levels of computation time and the speed of convergence. In summary, the Firefly algorithm is more suitable to exploit a search space by improving individuals' experience and simultaneously obtaining a population of local optimal solutions. I. INTRODUCTION The optimisation of systems and processes is very meaning to the efficiency and economics of many science and engineering domains. Optimisation problems are solved by using rigorous or approximate mathematical search techniques. Rigorous methods have employed linear programming, integer programming, dynamic programming or branch-and-bound techniques to approach the optimal solution for moderate-size problems. However, optimising real-life problems of the scale often encountered in
Coupling and cohesion measures for evaluation of component reusability

This paper provides an account of new measures of coupling and cohesion developed to assess the reusability of Java components retrieved from the internet by a search engine. These measures differ from the majority of established metrics in two respects: they reflect the degree to which entities are coupled or resemble each other, and they take account of indirect couplings or similarities. An empirical comparison of the new measures with eight established metrics shows the new measures are consistently superior at ranking components according to their reusability.
U.S. Evolving Macroeconomic Dynamics: A Structural Investigation

We fit a Bayesian time-varying parameters structural VAR with stochastic volatility to the Federal Funds rate, GDP deflator inflation, real GDP growth, and the rate of growth of M2. We identify 4 shocks–monetary policy, demand non-policy, supply, and money demand–by imposing sign restrictions on the estimated reduced-form VAR on a period-by-period basis. The evolution of the monetary rule in the structural VAR accords well with narrative accounts of post-WWII U.S. economic history, with (e.g.) significant increases in the long-run coefficients on inflation and money growth around the time of the Volcker disinflation. Overall, however, our evidence points towards a dominant role played by good luck in fostering the more stable macroeconomic environment of the last two decades. First, the Great Inflation was due, to a dominant extent, to large demand non-policy shocks, and to a lower extent to supply shocks. Second, imposing either Volcker or Greenspan over the entire sample period would only have had a limited impact on the Great Inflation episode, while imposing Burns and Miller would have resulted in a counterfactual inflation path remarkably close to the actual historical one. Although the systematic component of monetary policy clearly appears to have improved over the sample period, this does not appear to have been the dominant influence in post-WWII U.S. macroeconomic dynamics. JEL Classification: E32, E47, E52, E58
Implementation of IPv6 address generation mechanism for enterprise wireless local area network in open source DHCPv6

This paper discusses the implementation of IPv6 address generation/assignment mechanism proposed in [1] in Dibbler DHCPv6. In the mechanism, each user is assigned with random address which uniquely allocated for his/her exclusive use. It is shown that it can be incorporated into existing Dibbler software and tested under various network topologies. The proposed mechanism will enhance user privacy by dynamic address assignment and yet does not compromise network visibility since users can be traced individually regardless of dynamically changing IPv6.
Semantic Integration of Structured Data Powered by Linked Open Data

Recent advances in open data have resulted in vast amounts of tabular datasets containing valuable, actionable information to several stakeholders. However, information pertaining to any given entity is fragmented across several arbitrarily structured tables. There is a pressing need for semantic integration of such disparate datasets to enable deeper forms of inference and intelligence. This task is challenging because not only such datasets have no overarching schematic framework, there is also no overarching thematic framework. The datasets need not be about any one specific topic or theme. Hence, there is no one specific ontology onto which the datasets can be mapped. In this work we address the issue of mapping arbitrarily structured tabular data to one or more existing ontologies from the Linked Open Data Cloud (LOD) or abducing a new ontology around subsets of such tables. The overall objectives of this work called "Inferencing in the Large" aims to go further than this, to enrich mapped ontologies with inferencing rules and enable the use of semantic reasoners.
Ray travel times in range-dependent acoustic waveguides

An approximate analytical approach to describe the stochastic motion of sound rays in deep ocean is developed. This is done for a realistic propagation model with an internal wave induced perturbation imposed on the smooth background sound speed field. The chaotic ray dynamics is analyzed using the Hamiltonian formalism taken in terms of the action-angle canonical variables. It is shown that even at ranges of a few thousands km, the magnitude of range variations of the action variable is still small enough to be used as a small parameter in the problem. A simple expression for the difference in travel times of perturbed and unperturbed rays and approximate analytical solutions to stochastic ray (Hamilton) equations are derived. These relations are applied to study range variations of the timefront (representing ray arrivals in the time-depth plane). Estimations characterizing the widening and bias of timefront segments in the presence of perturbations are obtained. Qualitative and quantitative explanations are given to surprising stability of early portions of the timefront observed in both numerical simulations and field experiments. PACS number(s): 43.30. Cq, 43.30. Pc
Design and generation of adaptable Web information systems with KIWIS

Web-based information systems (WIS) are now widely used for diffusing and processing information over the network. Methodological guidelines which assist WIS developers in their task must take into account the specificities of WIS (hypermedia structured information, navigation features, etc.). This paper presents KIWIS, a generator of WIS, which addresses the issue of designing and automatically deploying such WIS. Using KIWIS, designers can specify, at a conceptual level, the features of the WIS to be generated. The features are made operational by KIWIS by instantiating different models dedicated to the description of the application domain, the expected functionalities, and some features concerning adaptability. Any WIS described and generated with KIWIS can be considered adaptable since users can progressively access the content of information while the presentation of information respects the graphical charters selected or defined by users.
Turbo space-time equalization of TCM for broadband wireless channels

This paper presents a space-time turbo (iterative) equalization method for trellis-coded modulation (TCM) signals over broadband wireless channels. For fixed wireless systems operating at high data rates, the multipath delay spread becomes large, making it impossible to apply trellis-based equalization methods. The equalizer proposed here consists of a broadband beamformer which processes antenna array measurements to shorten the observed channel impulse response, followed by a conventional scalar turbo equalizer. Since the applicability of trellis-based equalizers is limited to additive white noise channels, the beamformer is required to preserve the whiteness of the noise at its output. This constraint is equivalent to requiring that the finite-impulse response (FIR) beamforming filters must have a power complementarity property. The power complementarity property imposes nonnegative definite quadratic constraints on the beamforming filters, so the beamformer design is expressed as a constrained quadratic optimization problem. The composite channel impulse response at the beamformer output is shortened significantly, making it possible to use a turbo equalizer for the joint equalization and decoding of trellis modulated signals. The proposed receiver structure is simulated for two-dimensional TCM signals such as 8-PSK and 16-QAM and the results indicate that the use of antenna arrays with only two or three elements allows a large decrease in the channel signal-to-noise ratio needed to achieve a 10/sup -4/ bit-error rate.
Supervising practice based research

Practice based research appears to have emerged within several Higher Education agendas including the professional doctorates and the teacher as researcher. One way of thinking about this methodological approach is to consider its research paradigm – a practice based epistemology, and from this perspective to consider what special application to research supervision the paradigm invites. Within a “supervision as pedagogy” agenda these applications can be considered as pedagogies. This paper has been written in the style of practice based research, drawing on the author’s own experiences of supervising students undertaking practice based research. It adopts a position that research supervision is pedagogy and draws on the model of ‘Productive Pedagogies” to articulate strategies to help novice research students develop a research proposal.
Information Links and Electronic Marketplaces: The Role of Interorganizational Information Systems in Vertical Markets

Interorganizational information systems--i.e., systems spanning more than a single organization--are proliferating as companies become aware of the potential of these systems to affect interorganizational interactions in terms of economic efficiency and strategic conduct. This new technology can have a far-reaching impact on the structure of entire industries. This article identifies two types of interorganizational information systems: information links and electronic markets. It then explores how economic models can be employed to study the implications of information links for the coordination of individual organizations with their customers and their suppliers, and the implications of electronic market systems for efficiency and competition in vertical markets. Finally, the strategic significance of inter-organizational systems is addressed, and certain potential long-term impacts on the structure of markets, industries, and organizations are discussed.