bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sclerostin and Dickkopf-1 in Renal Osteodystrophy
Authors: Cejka Daniel , Herberth Johann , Branscum Adam J. , Fardo David W. , Monier-Faugere Marie-Claude , Diarra Danielle , Haas Martin , Malluche Hartmut H. 
Published: December 2010

SummaryBackground and objectivesThe serum proteins sclerostin and Dickkopf-1 (Dkk-1) are soluble inhibitors of canonical wnt signaling and were recently identified as components of parathyroid hormone (PTH) signal transduction. This study investigated the associations between sclerostin and Dkk-1 with histomorphometric parameters of bone turnover, mineralization, and volume in stage 5 chronic kidney disease patients on dialysis (CKD-5D).Design, setting, participants, & measurementsIn a cross-sectional study, 60 CKD-5D patients underwent bone biopsies followed by histomorphometry. Levels of sclerostin, Dkk-1, and intact PTH (iPTH) were determined in blood.ResultsSerum levels of sclerostin and iPTH correlated negatively. In unadjusted analyses, sclerostin correlated negatively with histomorphometric parameters of turnover, osteoblastic number, and function. In adjusted analyses, sclerostin remained a strong predictor of parameters of bone turnover and osteoblast number. An observed correlation between sclerostin and cancellous bone volume was lost in regression analyses. Sclerostin was superior to iPTH for the positive prediction of high bone turnover and number of osteoblasts. In contrast, iPTH was superior to sclerostin for the negative prediction for high bone turnover and had similar predictive values than sclerostin for the number of osteoblasts. Serum levels of Dkk-1 did not correlate with iPTH or with any histomorphometric parameter.ConclusionsOur data describe a promising role for serum measurements of sclerostin in addition to iPTH in the diagnosis of high bone turnover in CKD-5D patients, whereas measurements of Dkk-1 do not seem to be useful for this purpose.
Cardiorespiratory Fitness Is Independently Associated with 25-Hydroxyvitamin D in Chronic Kidney Disease
Authors: Petchey William G. , Howden Erin J. , Johnson David W. , Hawley Carmel M. , Marwick Thomas , Isbel Nicole M. 
Published: December 2010

Summary

Background and objectives
Vitamin D is an established important contributor to muscle function and aerobic metabolism. Hypovitaminosis D is highly prevalent in CKD patients and is associated with increased cardiovascular (CV) mortality via unknown mechanisms. Because aerobic-exercise capacity strongly predicts future CV events, we hypothesized that vitamin D status could be linked to CV outcomes via an effect on maximum aerobic-exercise capacity in patients with CKD and that this effect may be mediated in part via its actions on muscle strength and functional ability.

Design, setting, participants, & measurements
Baseline demographic, anthropometric, and biochemical data were collected in a cross-sectional study of patients with moderate CKD. Peak aerobic capacity was determined during treadmill stress testing using metabolic equivalence of tasks. Physical activity was assessed using the Active Australia questionnaire, grip strength by dynamometer, and functional capacity by “Up & Go” testing.

Results
The study included 85 participants (age 59.5 ± 9.7 years, 60% male, 44% diabetic, 92% Caucasian; mean serum 25-hydroxyvitamin D [25-OHD] 78.4 ± 29.4 nmol/L). We demonstrated that 25-OHD status was independently associated with aerobic-exercise capacity (β = 0.2; P = 0.008). Aerobic-exercise capacity was also predicted by younger age, white race, smaller waist circumference, absence of a previous angina history, and increasing weekly physical activity. However, neither muscle strength nor functional ability were significantly associated with 25-OHD.

Conclusions
Vitamin D is independently associated with aerobic capacity in CKD patients, and this finding is not explained by changes in muscle strength or functional ability.
Squirrel-cage motor drive dynamics modeling including chosen damages - programming tools
Authors: Sołbut Adam 
Published: December 2010

Squirrel-cage motor drive dynamics modeling including chosen damages - programming tools
Description of program tools simplifying simulation applications building for physical phenomenons described by differential equations in state equations form modeling is presented in the paper. A method for using prepared libraries for squirrel-cage motors including any motor damages modeling had been described. For that purpose, squirrel-cage motor mathematical model in natural coordinates system had been presented. Presented solutions provide also supply sources (inverters) modeling, including their microprocessor implementation and other phenomenons, that assume state equation structure step changes, depending on variable limitations and time value.
Corona current concept in lightning return-stroke models of engineering type
Authors: Masłowski Grzegorz 
Published: December 2010

Corona current concept in lightning return-stroke models of engineering typeA role of radial corona current in a lightning discharge is discussed in the paper. It is shown that the corona current concept previously introduced by Cooray for lightning return stroke models of distributed-current-source (DCS) type, and later, by Maslowski and Rakov for lumped-current-source (LCS) type models enables to show duality between these two types of models. Further, it is demonstrated that the corona current is useful during consideration of dynamics of the lightning-channel corona sheath. As an example of application of presented approach a relaxation model of charge motion in the corona sheath is analysed together with plots which show the rate of expansion and shrinkage of the lightning corona sheath on both microsecond and millisecond time scales.
Robustness of adaptive discrete-time LQG control for first-order systems
Authors: Królikowski A. , Horla D. 
Published: December 2010

Robustness of adaptive discrete-time LQG control for first-order systemsThe discrete-time adaptive LQG control of first-order systems is considered from robustness point of view. Both stability and performance robustness are analyzed for different control system structures. A case of amplitude-constrained control is presented, and application of certainty equivalence for self-tuning implementation is also discussed.
Information geometry of divergence functions
Authors: Amari S. , Cichocki A. 
Published: December 2010

Information geometry of divergence functionsMeasures of divergence between two points play a key role in many engineering problems. One such measure is a distance function, but there are many important measures which do not satisfy the properties of the distance. The Bregman divergence, Kullback-Leibler divergence andf-divergence are such measures. In the present article, we study the differential-geometrical structure of a manifold induced by a divergence function. It consists of a Riemannian metric, and a pair of dually coupled affine connections, which are studied in information geometry. The class of Bregman divergences are characterized by a dually flat structure, which is originated from the Legendre duality. A dually flat space admits a generalized Pythagorean theorem. The class off-divergences, defined on a manifold of probability distributions, is characterized by information monotonicity, and the Kullback-Leibler divergence belongs to the intersection of both classes. Thef-divergence always gives the α-geometry, which consists of the Fisher information metric and a dual pair of ±α-connections. The α-divergence is a special class off-divergences. This is unique, sitting at the intersection of thef-divergence and Bregman divergence classes in a manifold of positive measures. The geometry derived from the Tsallisq-entropy and related divergences are also addressed.
Towards human consistent data driven decision support systems using verbalization of data mining results via linguistic data summaries
Authors: Kacprzyk J. , Zadrożny S. 
Published: December 2010

Towards human consistent data driven decision support systems using verbalization of data mining results via linguistic data summariesWe present how the conceptually and numerically simple concept of a fuzzy linguistic database summary can be a very powerful tool for gaining much insight into the essence of data that may be relevant for a business activity. The use of linguistic summaries provides tools for the verbalization of data analysis (mining) results which, in addition to the more commonly used visualization e.g. via a GUI, graphical user interface, can contribute to an increased human consistency and ease of use. The results (knowledge) derived are in a simple, easily comprehensible linguistic form which can be effectively and efficiently employed for supporting decision makers via the data driven decision support system paradigm. Two new relevant aspects of the analysis are also outlined which was first initiated by the authors. First, following Kacprzyk and Zadrożny [1] comments are given on an extremely relevant aspect of scalability of linguistic summarization of data, using their new concept of a conceptual scalability that is crucial for large applications. Second, following Kacprzyk and Zadrożny [2] it is further considered how linguistic data summarization is closely related to some types of solutions used in natural language generation (NLG), which can make it possible to use more and more effective and efficient tools and techniques developed in this another rapidly developing area. An application of a computer retailer is outlined.
TuLiPA - Parsing extensions of TAG with range concatenation grammars
Authors: Kallmeyer L. , Maier W. , Parmentier Y. , Dellert J. 
Published: December 2010

TuLiPA - Parsing extensions of TAG with range concatenation grammarsIn this paper we present a parsing framework for extensions of Tree Adjoining Grammar (TAG) called TuLiPA (Tübingen Linguistic Parsing Architecture). In particular, besides TAG, the parser can process Tree-Tuple MCTAG with Shared Nodes (TT-MCTAG), a TAG-extension which has been proposed to deal with scrambling in free word order languages such as German. The central strategy of the parser is such that the incoming TT-MCTAG (or TAG) is transformed into an equivalent Range Concatenation Grammar (RCG) which, in turn, is then used for parsing. The RCG parser is an incremental Earley-style chart parser. In addition to the syntactic anlysis, TuLiPA computes also an underspecified semantic analysis for grammars that are equipped with semantic representations.
The art and science of large-scale disasters
Authors: Gad-El-Hak M. 
Published: December 2010

The art and science of large-scale disastersThe subject of large-scale disasters is broadly introduced in this article. Both the art and science of predicting, preventing and mitigating natural and manmade disasters are discussed. A universal, quantitative metric that puts all natural and manmade disasters on a common scale is proposed. Issues of prediction, control and mitigation of catastrophes are presented. The laws of nature govern the evolution of any disaster. In some cases, as for example weather-related disasters, the first-principles laws of classical mechanics could be written in the form of field equations, but exact solutions of these often nonlinear differential equations are impossible to obtain particularly for turbulent flows, and heuristic models together with intensive use of supercomputers are necessary to proceed to a reasonably accurate forecast. In other cases, as for example earthquakes, the precise laws are not even known and prediction becomes more or less a black art. Management of any type of disaster is more art than science. Nevertheless, much can be done to alleviate the resulting pain and suffering. The expansive presentation of the broad field of large-scale disasters precludes a detailed coverage of any one of the many topics touched upon. Three take-home messages are conveyed, however: a universal metric for all natural and manmade disasters is presented; all facets of the genre are described; and a proposal is made to view all disasters as dynamical systems governed for the most part by the laws of classical mechanics.
A new scheme for power factor correction and active filtering for six-pulse converters loads
Authors: Han Y. , Khan M. , Xu L. , Yao G. , Zhou L. , Chen C. 
Published: December 2010

A new scheme for power factor correction and active filtering for six-pulse converters loads
This paper presents a novel harmonic-free power factor correction (PFC) topology based on T-type active power filter (APF), which is dedicated for power factor improvement and harmonic filtering for six-pulse converter loads. The cascaded controller structure is adopted for the proposed system, namely, the inner current loop and outer voltage loop. The current-loop control scheme is based on a decoupled state-space equations of the T-type APF using separate proportional-integral (PI) controllers in d-axis and q-axis of the synchronous rotating reference frame (SRRF) synchronized with grid voltages, respectively. The fundamental components of load-side currents are feed forwarded in the current-loop using two groups of synchronous frame adaptive linear neural networks (ADALINEs) to ensure estimation accuracy and a fast dynamic response. A separate proportional-integral (PI) controller is adopted in the outer voltage loop for balancing the active power flow of the voltage source inverter (VSI) dc-side capacitor. The experimental results confirm well with the theoretical analysis.
Multi-objective decision making and search space for the evaluation of production process scheduling
Authors: Witkowski T. , Antczak P. , Antczak A. 
Published: December 2010

Multi-objective decision making and search space for the evaluation of production process schedulingOver the years, various approaches have been proposed in order to solve the multi-objective job-shop scheduling problem - particularly a hard combinatorial optimization problem. The paper presents an evaluation of job shop scheduling problem under multiple objectives (mean flow time, max lateness, mean tardiness, mean weighted tardiness, mean earliness, mean weighted earliness, number of tardy tasks). The formulation of the scheduling problem has been presented as well as the evaluation schedules for various optimality criteria. The paper describes the basic mataheuristics used for optimization schedules and the approaches that use domination method, fuzzy method, and analytic hierarchy proccess (AHP) for comparing schedules in accordance with multiple objectives. The effectiveness of the algorithms has been tested on several examples and the results have been shown. New search space for evaluation and generation of schedules has been created. The three-dimensional space can be used for the analysis and control of the production processes.
Repairable systems availability optimization under imperfect maintenance
Authors: Samet S. , Chelbi A. , Hmida F. 
Published: December 2010

Repairable systems availability optimization under imperfect maintenanceThis paper deals with the modeling of a preventive maintenance strategy applied to a single-unit system subject to random failures. According to this policy, the system is subjected to imperfect periodic preventive maintenance restoring it to ‘as good as new’ with probability p and leaving it at state ‘as bad as old’ with probability q. Imperfect repairs are performed following failures occurring between consecutive preventive maintenance actions, i.e the times between failures follow a decreasing quasi-renewal process with parametera. Considering the average durations of the preventive and corrective maintenance actions as well as their respective efficiency extents, a mathematical model is developed in order to study the evolution of the system stationary availability and determine the optimal PM period which maximizes it. The modeling of the imperfection of the corrective maintenance actions requires the knowledge of the quasi-renewal function. A new expression approximating this function is proposed for systems whose times to first failure follow a Gamma distribution. Numerical results are obtained and discussed.
Power electronic converter for photovoltaic systems with the use of FPGA-based real-time modeling of single phase grid-connected systems
Authors: Piróg S. , Stala R. , Stawiarski Ł. 
Published: December 2010

Power electronic converter for photovoltaic systems with the use of FPGA-based real-time modeling of single phase grid-connected systemsThe paper presents a method of investigation of grid connected systems with a renewable energy source. The method enables fast prototyping of control systems and power converters components by real-time simulation of the system. Components of the system such as energy source (PV array), converters, filters, sensors and control algorithms are modeled in FPGA IC. Testing the systems before its practical application reduces cost and time-to-market. FPGA devices are commonly used for digital control. The resources of the FPGAs used for preliminary testing can be sufficient for the complete system modelling. Debugging tools for FPGA enable observation of many signals of the analyzed power system (as a result of the control), with very advanced triggering tools. The presented method of simulation with the use of hardware model of the power system in comparison to classical simulation tools gives better possibilities for verification of control algorithms such as MPPT or anti-islanding.
Single phase full bridge inverter with coupled filter inductors and voltage doubler for PV module integrated converter system
Authors: Jiang Y. , Pan J. 
Published: December 2010

Single phase full bridge inverter with coupled filter inductors and voltage doubler for PV module integrated converter systemThis paper presents a single phase full bridge inverter with coupled filter inductors and voltage doubler for PV module integrated converter (MIC) system. In DC/DC stage, full bridge circuit with high frequency sinusoidal pulse width modulation control is used, and high frequency transformer with voltage doubler rectifier circuit to increase conversional ratio is adopted. Finally, at the conversion end the rectified sinusoidal waveforms is generated. The coupled filter inductors, which are placed in voltage doubler, not only reduce circulating current, which increases efficiency but also make the rectified output sinusoidal waveforms of DC/DC stage as smooth voltage source. In DC/AC stage, the full bridge circuit with line frequency square wave control is adopted to reduce switching losses and control cost. To verify the presented analysis a 100 W prototype single phase 220 VAC 50 Hz inverter output has been constructed and the experimental results are given.
Selected conducted electromagnetic interference issues in distributed power systems
Authors: Smoleński R. 
Published: December 2010

Selected conducted electromagnetic interference issues in distributed power systemsThis paper addresses the specific issues associated with electromagnetic compatibility that should be taken into account at the developmental stage of distributed systems. The main aim is to establish how far conducted interferences can penetrate the electric grid and how the group of converters, which individually meet EMC standards, influence the mains supply. The measured results of the spread of electromagnetic interference (EMI) current over a typical local electric grid and the low and medium voltage side of the power transformer are presented. The commonly applied, in distributed power systems, four-quadrant converter has been used as a test interference source. The limitations in the applicability of standardized methods for evaluation of aggregated conducted interferences have been presented in a system consisting of a group of two-quadrant frequency converter drives.
Control of PWM rectifier under grid voltage dips
Authors: Bobrowska-Rafał M. , Rafał K. , Abad G. , Jasiński M. 
Published: December 2010

Control of PWM rectifier under grid voltage dipsThis paper investigates control structure for grid connected three-phase two-level Voltage Source Converter (VSC) under distorted grid voltage conditions. Grid voltage is distorted by balanced and unbalanced voltage dips and higher harmonics. To address the problem, the control structure of converter is presented. The control system is a modification of Voltage Oriented Control (VOC) based on Dual Vector Current Controllers (DVCC). Grid synchronization under distorted voltage is achieved by employing Phase Locked Loop (PLL). Simulation and experimental results, which illustrate properties of proposed system, are presented.
Atomic mobilities and diffusivities in the fcc, L12and B2 phases of the Ni-Al system
Authors: Zhang Lijun , Du Yong , Chen Qing , Steinbach Ingo , Huang Baiyun 
Published: December 2010

AbstractA phenomenological model was utilized to describe diffusivities in the γ (fcc) /γü (L12) and A2/B2 phases of the NiüAl system. An effective strategy, which takes the homogeneity range and defect concentration into account, was developed in the present work to optimize the atomic mobilities of γü phase. Such a strategy results in a dramatic decrease in the number of atomic mobility parameters to be evaluated for the L12phase. The measured composition- and temperature- dependent diffusivities in the NiüAl system have been well replicated by the present mobility descriptions. For the L12phase, comprehensive comparisons show that with fewer model parameters the presently obtained mobilities yield a better fit to experimental diffusivities, compared with previous assessments. The mobility descriptions are further validated by comparing calculated and measured concentration profiles for various diffusion couples. The time-dependent Al composition profile for the annealed vapor Al / γ couple is accurately described for the first time.
Effect of grain boundary precipitates on vibration damping of FeüCrüMgüAl/Si alloy
Authors: Girish B. M. , Satish B. M. , Mahesh K. 
Published: December 2010

Abstract
The damping capacity of three different FeüCrüMgüAl/Si alloys was measured using the conventional cantilever beam method. The samples were heat-treated in vacuum at 1100°C for 1 h followed by slow cooling (120°C hü1). The vibration damping capacity of the alloys was definitely influenced by the amount of grain boundary precipitates as well as by the chromium concentration in the precipitates. The three different alloys investigated were FeüCrüMgüAl, FeüCrüMgüSi, and FeüCrüMgüAlüSi. It was found that the FeüCrüMgüAlüSi alloy exhibits the highest damping capacity with the smallest amount of grain boundary precipitates and least chromium concentration. Among the remaining alloys, although the chromium concentrations in the grain boundary precipitates were almost the same, the amount of grain boundary precipitates in FeüCrüMgüAl was lower than in FeüCrüMgüSi, and hence the damping capacity of FeüCrüMgüAl was higher than the other.