bluuebunny/crossref_metadata_2025_split huggingface dataset:
Automated peritoneal dialysis in Hong Kong: There are two distinct groups of patients
Authors: Kwan Bonnie Ching‐Ha , Chow Kai‐Ming , Ma Terry King‐Wing , Yu Vincent , Law Man‐Ching , Leung Chi‐Bon , Li Philip Kam‐Tao , Szeto Cheuk‐Chun 
Published: March 2013

AbstractAimTo compare the clinical outcome between continuous ambulatory peritoneal dialysis (CAPD) and automated peritoneal dialysis (APD) in specific subgroups of patients.MethodsWe reviewed the clinical outcome of 90 consecutive incident APD patients and 180 CAPD patients in our centre.ResultsThe median follow up was 21.9 months (inter‐quartile range, 9.5 to 46.5 months). The APD group was younger and had a lower Charlson's score than the CAPD group. Furthermore, the APD group had a highly skewed distribution of the Charlson's score, indicating the possibility of two different groups of patients. Multivariate analysis showed that in addition to the treatment mode (APD vs CAPD) and Charlson's score, there was a significant interaction between the two (P = 0.043) on patient survival. For patients with Charlson's score ≤6, the APD group had a significantly better patient survival than the CAPD group (78.3% vs 65.4% at 5 years, P = 0.039), while for patients with Charlson's score ≥7, the APD group had a worse patient survival than the CAPD group (16.3% vs 48.4% at 5 years, P = 0.028). Similarly, Charlson's score and its interaction with treatment mode, but not the APD group per se, were independent predictors of technique survival (P = 0.013). For patients with Charlson's score ≥7, the APD group had a significantly lower technique survival than the CAPD group (8.8% vs 34.3%, P = 0.001), while for patients with Charlson's score ≤6, the technique survival was similar (44.4% vs 42.5%, P = 0.15). Peritonitis‐free survival was 35.2% and 32.2% for APD and CAPD groups, respectively (P = 0.021), and the difference was not affected by Charlson's score.ConclusionsComorbid diseases had a significant interaction with the mode of PD on patient and technique survival of incident PD patients. Our result suggests that APD may offer benefit in, and only in, young patients with minimal comorbid diseases.
A rare case of calibre persistent labial artery presenting as a mucocoele
Authors: Aga F. , Mukhtar Z. , Hardee P. 
Published: March 2013

AbstractWe present a case of a patient presenting with a lesion consistent with a mucocoele on the lower labial mucosa, which upon biopsy instead revealed a rare anomaly called a ‘calibre persistent artery’. The aim of this article is to bring this rarely reported lesion to the attention of clinicians, and to emphasise the importance of correct assessment of a lump.
On the Constitutive Property Reply: Commentary onCampbell
Authors: Moore Dwayne 
Published: March 2013

AbstractFor the nonreductive physicalist, behavioural effects have a complete physiological explanation and a distinct psychological explanation. In a series of papersJaegwonKim argues that there can be no more than a single complete and independent explanation of any one event, thereby excluding the psychological explanation. For his own part,Kim includes psychological explanations through the use of an extensional model of explanatory individuation. Numerous critics have pointed out the counterintuitive results of this extensional model of explanatory individuation. In a recent article in this journal,NeilCampbell suggests thatKim's property exemplification account of events provides the conceptual resources to dodge this objection. In this article I argue that this appeal to the property exemplification account does not work in the crucial case of mental explanation.
Control of Dynamic Responses of Towerlike Offshore Structures in
Waves
Authors: Yoshida K. , Suzuki H. , Oka N. 
Published: March 2013

Abstract
This paper presents a preliminary attempt to control the dynamic response of a towerlike offshore structure subjected to regular waves. The structures are modeled in two ways. One is a vertical rigid pipe supported at the lower end by a pin joint. The other is a vertical flexible pipe fixed at the lower end. The formulation of the optimal control shows that the control consists of a feedback control and a feedforward control based on the disturbance. In this research, two types of feedforward control are employed apart from the optimality. One is to compensate the entire wave forces acting on the structure. The other is on-off control to compensate the principal Fourier component of the wave forces by using the three states of the thruster, forward, stop and backward. The displacement and deformation of the structures were measured by an ultrasonic measurement system. The surface elevation was measured by a capacitance-type wave height meter. These data were sampled and processed by a 16-bit microprocessor, and the thrust was applied by a propeller-type thruster. The performance of the control was satisfactory, and the responses of the controlled structure were reduced to about 30 percent of those of the uncontrolled system.
Time Series Generation and Transformation—The Role of
Phase
Authors: Jefferys E. R. 
Published: March 2013

Abstract
Random signals with some desired power spectrum may be generated by a variety of methods, including summation of sinusoids, convolution of white noise with a kernel function or integration of a differential equation driven by white noise. These continuous models of the spectrum have discrete time equivalents, the moving average (MA) and autoregressive moving average (ARMA), respectively. This paper relates the various techniques and discusses a problem which appears in all of them. Each method involves an amplitude function, the square root of the desired power spectrum and some phase behavior which is unknown and must therefore be assumed. Results from the time series literature presented here provide a rational basis for the choice of phase. In the convolution method, the resulting kernel function is the shortest possible, consistent with the given spectrum and hence minimizes the computational cost of the subsequent signal generation. The corresponding differential equation is the simplest possible, consistent with the form of the amplitude curve. No properties of the time series are affected by the assumed phase spectrum, but phase is critical to the synthesis of correlated signals such as velocity at different points in a random wave field. The results are illustrated by a nondimensional fourth-order differential equation model of the Pierson-Moskowitz spectrum.
Random Response of Offshore Towers With Pile-Soil-Pile
Interaction
Authors: Novak M. , Mitwally H. 
Published: March 2013

Abstract
Dynamic pile-soil-pile interaction is analyzed using dynamic interaction factors. For pile groups, complex stiffness matrices are formulated in closed form for excitation in all vibration modes and introduced into the analysis of an offshore tower. The effects of dynamic pile-soil-pile interaction on tower response to random wave forces are demonstrated. Temporal as well as spatial randomness of wave forces are considered.
Operational Risk Evaluation of an Ice Feature Impact
Authors: Dunwoody A. B. 
Published: March 2013

Abstract
The risk of impact by a particular ice feature in the vicinity of an offshore structure or stationary vessel is of concern during operations. A general method is presented for calculating the risk of an impact in terms of the joint probability distribution of the forecast positions and velocities of the ice feature. A simple stochastic model of the motion of an ice feature is introduced for which the joint probability distribution of ice feature position and velocity can be determined as a function of time. The risk of an impact is presented for this model of the motion of an ice feature. Predictions of the distributions of the time until impact and the drift speed upon impact are also presented and discussed. Predictions are compared against results of a Monte Carlo simulation.
Feeling Free Despite LBZ
Authors: de Koning A. C. , Harston J. D. , Nayler K. D. , Ohm R. K. 
Published: March 2013

Abstract
It is sometimes argued that the occurrence of local brittle zones (LBZs) is a new phenomenon relevant only to modern low-carbon steels, while others claim that such LBZs are also present in the heat-affected zones of the C-Mn steels of the late sixties/seventies. In order to elucidate on this matter, both an “old” normalized (N) steel (1970s) and two modern low-carbon types of steel, normalized (N) and controlled rolled-accelerated cooled (CONRAC) have been investigated and compared with each other. In addition, consideration has been given to the correlation between the level of heat input during welding and the occurrence of local brittle zones. This has led in practice to a restriction of the heat input to 3.5 kJ/mm maximum for the modern low-carbon normalized steel investigated, which was used in recent projects. Furthermore, the engineering significance of LBZs is considered in the light of design aspects. It is concluded that there is little reason for concern with respect to a detrimental effect of LBZs in tubular connections of offshore structures, which is supported by a satisfactory performance of the latter to date.
Catchment Regions of Multiple Dynamic Responses in Nonlinear Problems
of Offshore Mechanics
Authors: Virgin L. N. , Bishop S. R. 
Published: March 2013

Abstract
Consideration of nonlinear effects in the dynamic analysis of offshore structures leads to complex phenomena even for relatively simple deterministic mathematical models. Nonlinearity in the stiffness or restoring force of a structure can be conveniently incorporated into a differential equation of motion, which can then be solved either analytically, using perturbation techniques, or numerically for various parameter ranges and forcing conditions. A particular feature of nonlinear dynamics is the appearance of multiple, competing steady-state oscillations which depend crucially on initial conditions. These coexisting stable solutions can be thought of as attractors for transient motion. A central question is therefore: How does the final long-term behavior of a dynamical system depend on the starting conditions? This paper concentrates on the computation of the domains of attraction or catchment regions using numerical techniques based on Poincare mapping ideas. The three specific examples illustrated are the roll motion of a ship, the oscillations of an articulated column and the surge response of a moored semi-submersible. This work may be considered an extension of previous work by the same authors.
Experimental Evaluation of Damping in a Steel Tubular Member of an
Offshore Platform Jacket in Air
Authors: Mason A. B. , Ullmann R. R. 
Published: March 2013

Abstract
Pluck tests were performed on a major diagonal member of an offshore platform jacket in the fabrication yard to develop data for assessment of structural damping. The initial displacements were varied in order to investigate dependence of damping on amplitude. The response histories were typically composed of six or seven vibrational modes having closely spaced frequencies in the 3.4–4.2-Hz range. System identification was accomplished using an output error approach. Response histories reconstructed from the system parameters identified by this method exhibit excellent fidelity to the corresponding recorded data traces. The analysis results support the assumption of linear system behavior and lead to a suggested value of 0.002 for the critical damping ratio.
Approximation of B-Spline Geometries With Lower Degree
Representations
Authors: Patrikalakis N. M. , Bardis L. , Kriezis G. A. 
Published: March 2013

Abstract
Exchange of data between geometric modeling systems of different inherent capabilities frequently requires approximate conversion of high degree, piecewise, polynomial curves and surface patches to lower degree representations. The objective of this work is to provide reliable methods for the approximation of high-order B-spline curves and surface patches by low-order B-spline representations. Our method guarantees a prespecified accuracy at all isoparametric points of the curve and patch, a critical feature for accurate exchange of data.
The Significance of Local Brittle Zones to the Integrity of Large
Welded Structures
Authors: Bateson P. H. , Webster S. E. 
Published: March 2013

Abstract
An extensive group-sponsored research program has been carried out within the UK, which, supplemented by additional work by British Steel, was designed to study the structural significance of local brittle zones. Charpy impact, CTOD and wide plate tests have been examined in order to compare and contrast their fracture behavior under similar conditions. In order to permit this comparison, two welding conditions were studied giving nominally 30 and 10 percent of coarse-grained HAZ through the thickness of a 50-mm-thick plate. The high percentage of coarse grain condition was tested in the as-welded and PWHT state and the low percentage condition as-welded only. It was shown that low toughness (&lt;0.1 mm CTOD) measurements could be obtained using both through thickness and surface-notched test pieces over a temperature range of −30 to +10°C. Similar minimum toughness values were obtained for all the test conditions studied, but the frequency of occurrence varied. Twenty-two wide plate tests were carried out and nine fractured, four in the as-welded condition (two each for the two welding variables studied) and five in the PWHT condition. A further plate initiated a fracture from a bevel weld procedure which arrested in the parent plate. It is postulated that the requirement for an extreme combination of stress level, defect size and coarse-grained microstructure at the crack tip plus the potential for crack arrest is the reason for the absence of fractures in offshore structures.
Reliability Analysis of a Mono-Tower Platform
Authors: Kirkegaard P. H. , Enevoldsen I. , So̸rensen J. D. , Brincker R. 
Published: March 2013

Abstract
In this paper, a reliability analysis of a Mono-tower platform is presented. The failure modes considered are yielding in the tube cross sections and fatigue failure in the butt welds. The fatigue failure mode is investigated with a fatigue model, where the fatigue strength is expressed through SN relations. In determining the cumulative fatigue damage, Palmgren-Miner’s rule is applied. Element reliability, as well as systems reliability, is estimated using first-order reliability methods (FORM). The sensitivity of the systems reliability to various parameters is investigated. It is shown that the fatigue limit state is a significant failure mode for the Mono-tower platform. Further, it is shown for the fatigue failure mode that the largest contributions to the overall uncertainty are due to the damping ratio, the inertia coefficient, the stress concentration factor, the model uncertainties, and the parameters describing the fatigue strength.
Theoretical and Experimental Prediction of the Response of Compliant
Risers
Authors: Patrikalakis N. M. , Maekawa T. , Kriezis G. A. , Gursoy H. N. 
Published: March 2013

Abstract
The general three-dimensional linearized dynamic equations of a compliant riser, idealized as a rotationally nonuniform rod, around a nonlinear static configuration in the presence of general current and monochromatic wave excitation are formulated. Nonlinear forces such as quadratic drag are harmonically linearized by minimizing the mean square error between the linear approximation and the nonlinear force. The theory is implemented in a computer program which allows analysis of a variety of compliant riser configurations. Numerical examples for catenary risers are included. Comparisons of our theoretical predictions with experimental results obtained from a 1.5-m catenary compliant riser model excited monochromatically at the top parallel to a constant current are also presented to evaluate our ability to predict the response of compliant riser systems.
The Influence of Shape on Iceberg Wave-Induced Velocity
Statistics
Authors: Lever J. H. , Sen D. , Attwood D. 
Published: March 2013

Abstract
The motion response of small icebergs in waves has been the subject of recent investigation to provide information for the design of offshore structures resistant to glacial ice impact. Since sea state and iceberg size are random variables, probabilistic formulations have been developed for use in risk analysis-based design procedures. The present work discusses the influence of iceberg shape on its motion response in waves. Wave tank tests were conducted which show that model shape has a significant effect on wave-induced ice motion. For all models tested, however, response spectra in an irregular sea could be accurately estimated using the linear superposition of measured responses in regular waves and the measured wave energy spectra. This was true in spite of obvious nonlinear behavior exhibited in high model seas. The observed differences in wave-induced motion for differently shaped models with similar masses and characteristic lengths suggest that iceberg shape should also be treated as a random variable in probabilistic formulations. In this way, wave-induced ice motion may be represented as a function of sea state, iceberg mass or characteristic length, and iceberg shape, all random variables. An earlier risk analysis formulation is extended to incorporate the influence of randomly varying iceberg shape on ice/structure impact velocity statistics.
Three-Dimensional Ductile Constitutive Equation for
Ice
Authors: Santaoja K. 
Published: March 2013

Abstract
In the present paper the constitutive equation for polycrystalline materials, such as ice at wide temperature and strain rate range, is studied. The following deformation mechanisms of the material are examined: instantaneous linear elasticity, viscoelasticity, and viscoplasticity. The uniaxial material model is based on the theory proposed by Sinha. The delayed elastic strain is predicted by the modification introduced by Ashby and Duval to the equation of Sinha. A multiaxial theory to represent the reponse of isotropic polycrystalline material is developed. The multiaxial material model, called the SADS-model, coincides in case of uniaxial tension with the Ashby and Duval modification of the equations proposed by Sinha.
Elastic-Plastic Analysis of a Radially Loaded Spherical
Shell
Authors: Brooks G. N. , Leung C.-P. 
Published: March 2013

Abstract
An elastic-plastic analysis of a spherical shell loaded radially through a rigid inclusion is performed. The sphere is modeled as a shallow shell of infinite extent. The Tresca yield condition is used to derive the elastic-plastic moment-curvature relationship in a simple form. This is used to develop a computationally efficient solution method.
Rupture Hardware Minimization in Pressurized Water Reactor
Piping
Authors: Mukherjee S. K. , Szy Slow Ski J. J. , Chexal V. , Norris D. M. , Goldstein N. A. , Beaudoin B. F. , Quiñones D. F. , Server W. L. 
Published: March 2013

Abstract
For much of the high-energy piping in light water reactor systems, fracture mechanics calculations can be used to assure pipe failure resistance, thus allowing the elimination of excessive rupture restraint hardware both inside and outside containment. These calculations use the concept of leak-before-break (LBB) and include part-through-wall flaw fatigue crack propagation, through-wall flaw detectable leakage, and through-wall flaw stability analyses. Performing these analyses not only reduces initial construction, future maintenance, and radiation exposure costs, but also improves the overall safety and integrity of the plant since much more is known about the piping and its capabilities than would be the case had the analyses not been performed. This paper presents the LBB methodology applied at Beaver Valley Power Station—Unit 2 (BVPS-2); the application for two specific lines, one inside containment (stainless steel) and the other outside containment (ferritic steel), is shown in a generic sense using a simple parametric matrix. The overall results for BVPS-2 indicate that pipe rupture hardware is not necessary for stainless steel lines inside containment greater than or equal to 6-in. (152-mm) nominal pipe size that have passed a screening criteria designed to eliminate potential problem systems (such as the feedwater system). Similarly, some ferritic steel line as small as 3-in. (76-mm) diameter (outside containment) can qualify for pipe rupture hardware elimination.
Damage Assessment Analysis of Composite Pressure Vessels Subjected to
Random Impact Loading
Authors: Yener M. , Wolcott E. 
Published: March 2013

Abstract
At the present time, advanced composites have been widely accepted as engineering materials. Analysis techniques for the response of composite materials and structures to static loads are reasonably well established. Because of their light weight, high modulus, high strength, and good fatigue resistance, carbon fiber composites have been used successfully in the aircraft industry and rocket motor cases. However, composite materials are very susceptible to low velocity and low energy impact damage. Recently, the damage inflicted by such impact has been a subject of great interest. This paper primarily illustrates that it is possible to quantitatively assess damage due to any type of unexpected loading, including impact, using progressive failure finite element analysis.
Local Effects and Defect Criticality in Homogeneous and Laminated
Structures
Authors: Pindera J. T. 
Published: March 2013

Abstract
The paper presents a theoretical framework of a more comprehensive methodology of analysis of behavior of homogeneous and composite materials and structures. The behavior of bolted flanged connections is taken as an illustrative example. Particular attention is given to the local effects. The term “local effects” denotes the actual, pronounced local three-dimensional stress states which exist in particular regions of the actual, weakly three-dimensional, stress fields occurring in plates and shells. Presented examples show that the local effects can be one of the major causes of failures of homogeneous or composite laminated structures. Within the chosen theoretical framework, an outline of new analytical/experimental methods is presented, called isodyne methods. It is demonstrated that the isodyne methods allow the determination of the normal and shear components of the stress states in plates and beams, including the three-dimensional stress states at the crack tips, tips of local disbounds or defects, or in the lamination planes.
Effect of Shear Deformation on Bending of Laminated Composite
Beams
Authors: Gordaninejad F. , Ghazavi A. 
Published: March 2013

Abstract
A higher-order shear deformation beam theory is utilized to analyze the bending of thick laminated composite beams. This theory accounts for parabolic distribution of shear strain through the thickness of the beam. The predicted displacements show improvement over the Bresse-Timoshenko beam theory. Mixed finite element results are obtained for those cases where closed-form solutions are not available. The finite element and exact solutions are in close agreement. Numerical results are presented for single, two and three-layer beams under uniform and sinusoidal distributed transverse loadings.