bluuebunny/crossref_metadata_2025_split huggingface dataset:
Self‐Control as a Normative Capacity
Authors: Kalis Annemarie 
Published: October 2017

AbstractRecently, two apparent truisms about self‐control have been questioned in both the philosophical and the psychological literature: the idea that exercising self‐control involves an agent doing something, and the idea that self‐control is a good thing. Both assumptions have come under threat because self‐control is increasingly understood as a mental mechanism, and mechanisms cannot possibly be good or active in the required sense. However, I will argue that it is not evident that self‐control should be understood as a mechanism, suggesting that we might also argue the other way around: if we have independent reason to hold onto the idea that self‐control is inherently good and active, the conclusion might be that self‐control cannot be a mechanism. I will show that Aristotle's original analysis of self‐control actually offers grounds for both assumptions: he took there to be conceptual connections between self‐control and goodness/activity. By examining these connections, I argue that an Aristotelian approach could offer promising leads for a contemporary non‐mechanistic understanding of self‐control as a normative capacity.
Help not needed? Optimal host country regulation of expatriate NGO workers
Authors: Glazer Amihai , Jansen Hagen Rune , Rattsø Jørn 
Published: October 2017

AbstractMotivated by interventions in poor countries to increase the use of local labor in foreign nongovernmental organizations (NGOs), we address the behavior of these organizations under host government regulation. We extend existing NGO models by distinguishing between local workers and expatriates. The model covers both NGO monopoly and competition in the market for donations. Assuming that NGOs maximize output, we show that regulations in the form of a quota on the number of expatriates or a work permit fee for foreigners reduces NGO output, but increases employment of locals. The optimal quota is more likely to bind in the market structure generating the highest total fundraising surplus. An optimal work permit fee is equivalent to an optimal quota in both the monopoly and duopoly cases. For both instruments, the optimal tightness of regulation is decreasing in the weight the government attaches to the public good relative to domestic incomes and in the importance of NGO output to the supply of the public good. Aggregate NGO output and the level of the public good produced could be higher with a monopoly NGO.
Achilles and patellar tendinopathy display opposite changes in elastic properties: A shear wave elastography study
Authors: Coombes B. K. , Tucker K. , Vicenzino B. , Vuvan V. , Mellor R. , Heales L. , Nordez A. , Hug F. 
Published: October 2017

To compare tendon elastic and structural properties of healthy individuals with those with Achilles or patellar tendinopathy. Sixty‐seven participants (22 Achilles tendinopathy, 17 patellar tendinopathy, and 28 healthy controls) were recruited between March 2015 and March 2016. Shear wave velocity (SWV), an index of tissue elastic modulus, and tendon thickness were measured bilaterally at mid‐tendon and insertional regions of Achilles and patellar tendons by an examiner blinded to group. Analysis of covariance, adjusted for age, body mass index, and sex was used to compare differences in tendon thickness and SWV between the two tendinopathy groups (relative to controls) and regions. Tendon thickness was included as a covariate for analysis of SWV. Compared to controls, participants with Achilles tendinopathy had lower SWV at the distal insertion (Mean difference MD; 95% CI: −1.56; −2.49 to −0.62 m/s; P < .001) and greater thickness at the mid‐tendon (MD 0.19; 0.05‐0.33 cm; P = .007). Compared to controls, participants with patellar tendinopathy had higher SWV at both regions (MD 1.25; 0.40‐2.10 m/s; P = .005) and greater thickness proximally (MD 0.17; 0.06‐0.29 cm; P = .003). Compared to controls, participants with Achilles and patellar tendinopathy displayed lower Achilles tendon elastic modulus and higher patellar tendon elastic modulus, respectively. More research is needed to explore whether maturation, aging, or chronic load underlie these findings and whether current management programs for Achilles and patellar tendinopathy need to be tailored to the tendon.
The effects of topical aqueous sirolimus on tear production in normal dogs and dogs with refractory dry eye
Authors: Spatola Ronald , Nadelstein Brad , Berdoulay Andrew , English Robert V. 
Published: October 2017

AbstractPurposeTo evaluate the effect of twice daily aqueous 0.02% sirolimus drops on tear production in normal dogs and dogs with refractory keratoconjunctivitis sicca (KCS).MethodsTwo groups of dogs were studied. Ten normal dogs with no signs of ocular disease were administered topical 0.02% sirolimus ophthalmic solution in right eye, and a vehicle control in the left eye twice daily for 4 weeks. Complete ophthalmic examinations, including Schirmer tear test were performed weekly. Eighteen dogs with refractoryKCSwere randomly assigned to receive 0.02% sirolumus ophthalmic solution or 0.02% tacrolimus ophthalmic solution twice daily. Complete ophthalmic examinations were was performed at 2 and 6 weeks following treatment.ResultsTear production in the sirolimus‐treated eyes of normal dogs was greater when compared to vehicle controls with a mean difference over all time points of 3.46 mm (95%CI1.17, 5.75;P= 0.006). After 4 weeks of treatment, the mean difference was 5 mm (95%CI1.95, 8.05;P= 0.002). In dogs with refractory dry eye, 37.5% of eyes treated with sirolimus exhibited increased tear production >4 mm/min after 6 weeks of treatment, compared to 20% of eyes receiving tacrolimus (P= 0.433). One normal dog experienced topical irritation to both sirolimus and vehicle‐treatment. Side effects were not reported in any treated eyes with chronicKCS.ConclusionTopical 0.02% sirolimus might be an alternative treatment for canine patients with keratoconjunctivits sicca. The drug appears safe when applied topically in an aqueous suspension for up to 6 weeks. While initial results are promising, further studies are warranted.
Extracellular Cl− regulates electrical slow waves and setting of smooth muscle membrane potential by interstitial cells of Cajal in mouse jejunum
Authors: Saravanaperumal Siva Arumugam , Gibbons Simon J. , Malysz John , Sha Lei , Linden David R. , Szurszewski Joseph H. , Farrugia Gianrico 
Published: October 2017

New Findings
What is the central question of this study?
The aim was to investigate the roles of extracellular chloride in electrical slow waves and resting membrane potential of mouse jejunal smooth muscle by replacing chloride with the impermeant anions gluconate and isethionate.

What is the main finding and its importance?
The main finding was that in smooth muscle cells, the resting Cl− conductance is low, whereas transmembrane Cl− movement in interstitial cells of Cajal (ICCs) is a major contributor to the shape of electrical slow waves. Furthermore, the data confirm that ICCs set the smooth muscle membrane potential and that altering Cl− homeostasis in ICCs can alter the smooth muscle membrane potential.

Intracellular Cl− homeostasis is regulated by anion‐permeable channels and transporters and contributes to excitability of many cell types, including smooth muscle and interstitial cells of Cajal (ICCs). Our aims were to investigate the effects on electrical activity in mouse jejunal muscle strips of replacing extracellular Cl− (Cl−o) with the impermeant anions gluconate and isethionate. On reducing Cl−o, effects were observed on electrical slow waves, with small effects on smooth muscle membrane voltage (Em). Restoration of Cl− hyperpolarized smooth muscle Em proportional to the change in Cl−o concentration. Replacement of 90% of Cl−o with gluconate reversibly abolished slow waves in five of nine preparations. Slow waves were maintained in isethionate. Gluconate and isethionate substitution had similar concentration‐dependent effects on peak amplitude, frequency, width at half peak amplitude, rise time and decay time of residual slow waves. Gluconate reduced free ionized Ca2+ in Krebs solutions to 0.13 mm. In Krebs solutions containing normal Cl− and 0.13 mm free Ca2+, slow wave frequency was lower, width at half peak amplitude was smaller, and decay time was faster. The transient hyperpolarization following restoration of Cl−o was not observed in W/Wv mice, which lack pacemaker ICCs in the small intestine. We conclude that in smooth muscle cells, the resting Cl− conductance is low, whereas transmembrane Cl− movement in ICCs plays a major role in generation or propagation of slow waves. Furthermore, these data support a role for ICCs in setting smooth muscle Em and that altering Cl− homeostasis in ICCs can alter smooth muscle Em.
Extending the Limits for Thick Walled Pipe (D/t<20) for External Pressure and Combined Loading
Authors: Smienk Henk , Karjadi Erwan , Huiskes Steven 
Published: October 2017

During the operational and installation phase of submarine pipelines, the collapse and local buckling behaviour is of interest. Existing research [1] shows conservatism in the pure collapse DNV formula for thick walled pipe. The first part of the paper will focus on the collapse behaviour of empty thick walled pipe under external pressure. Using 2D and 3D FE Analysis an investigation into the collapse behaviour of pipe with a D/t < 20 is conducted. The analysis also covers an extensive sensitivity analysis with regard to geometrical imperfections and different material models.
The local buckling behaviour during the combined external pressure, bending moment and effective axial force loading encountered in the sagbend is also investigated. To obtain a realistic load path for the sagbend loading, static Flexcom analyses are performed. If the load case is not sufficient to initiate collapse because of the stiffness of the catenary due to the low D/t, the pipe will be bent to the limit state while setting the effective tension to zero.
The effect of each sensitivity on the collapse and local buckle behaviour of thick walled pipe in the sagbend including effective axial tension is discussed.
Study of Self-Propelled Pufferfish Driven by Multiple Fins: A Comparison Between Rigid and Deformable Fins
Authors: Li Ruoxin , Xiao Qing , Li Lijun , Liu Hao 
Published: October 2017

In this work, we numerically studied the steady swimming of a pufferfish driven by the undulating motion of its dorsal, anal and caudal fins. The simulations are based on experimentally measured kinematics. To model the self-propelled fish swimming, a Computational Fluid Dynamics (CFD) tool was coupled with a Multi-Body-Dynamics (MBD) technique.
It is widely accepted that deformable/flexible or undulating fins are better than rigid fins in terms of propulsion efficiency. To elucidate the underlying mechanism, we established an undulating fins model based on the kinematics of live fish, and conducted a simulation under the same operating conditions as rigid fins. The results presented here agree with this view by showing that the contribution of undulating fins to propulsion efficiency is significantly larger than that of rigid fins.
Movement of a Sphere on a Flat Wall in Non-Newtonian Shear Flow
Authors: Ignatenko Yaroslav , Bocharov Oleg , May Roland 
Published: October 2017

For a particle on a wall or cuttings bed in a multiphase flow in confined geometries a condition for onset and lift-off is very important. In this case, a fundamental problem of hydrodynamic forces and torque acting on a particle moving near and on the wall in a viscous fluid needs to be solved.
In this paper, systematical simulation of a flow was performed around a perfect rolling or sliding spherical particle near the wall. A shear flow of Newtonian and Herschel-Bulkley fluids was investigated. The simulation was conducted for Reynolds numbers up to 200 and the dimensionless positive particle velocity Vp < 1.4. The relative particle velocity was made dimensionless by dividing it by the incoming flow velocity in front of the particle. The simulation was performed using the open-source CFD package OpenFOAM. The simulation results for Newtonian fluid agree with data presented in the literature.
For the particle’s low translational velocity the drag force coefficient in the non-Newtonian fluid is lower than in Newtonian fluid, but for increasing translational velocity the drag force coefficient increases.
The lift force coefficient behavior is non-monotonic versus rheology parameters. Lift and drag force show a sudden drop for very small translational velocities.
Our simulation shows that in the case of large Bingham numbers the particle’s lift force can be negative for steady perfect particle rolling. Thus, friction between particle and surface prevents particle’s take-off in some cases.
Knowing the dependence of the lift force on Reynolds number and rheological parameters allows one to determine incipient motion and take-off conditions for a spherical particle.
A Numerical Study of the Descent and Ascent Motion of a Full Ocean Depth Human Occupied Vehicle
Authors: Jiang Zhe , Shen Xiaochan , Hu Yong , Cui Weicheng 
Published: October 2017

To meet the needs of scientific discoveries in hadal zones, the hadal science and technology center (HAST) of Shanghai Ocean University has made a significant commitment to construct a movable laboratory for hadal trenches in 2013, which includes a mothership, an full ocean depth (FOD) human occupied vehicle (HOV), an FOD Autonomous and Remotely-operated Vehicle (ARV) and several FOD landers. Presently, the HOV is in concept design phase.
Current HOVs in service could only work below 7,000m. To increase the submergence depth from 7,000m to 11,000m for a FOD HOV, the time spending in descent and accent will take a majority part of power endurance and leave little time in scientific studies. Hence, the descent/ascent motion analysis and optimization will play a bigger role in FOD HOV designs contrasting to current HOVs.
In this paper, in order to investigate resistance characteristics and drag coefficients in decent and ascent directions of the FOD HOV, the Reynolds Averaged Navier-Stokes (RANS) equations were solved using computational fluid dynamics. To achieve a faster descent and ascent process, diving and floating with various attacking angles were tried. The numerical analysis for each scenario has been conducted and results were discussed. The method and theory presented in the paper will be applied to the design of a practical deep manned submersible.
Ductile Damage Study of Defective Girth Welds for Oil and Gas Pipeline: A Tailored Numerical and Finite Element Method Calibration From SENT Fracture Mechanics Test
Authors: Bruschi Roberto , Rossi Marco , Di Michele Alex , Scarsciafratte Daniele , Torselletti Enrico 
Published: October 2017

In this paper, the evolution of ductile damage in pipe girth welds for offshore pipelines application is studied with the use of Finite Element Analysis. To this purpose, the Gurson-Tvergaard-Needlmen (GTN) model is calibrated and applied to different finite element simulations. Saipem internally developed software, written in Matlab® environment, is used to automatically calibrate the Gurson model from experimental data and run several Finite Element Models of the pipe with different flaws in the girth weld.
The objective of this paper is to present and discuss this numerical tool, developed by Saipem coupling a Matlab® GUI and the ABAQUS FE solver. The tool allows speeding up and automatizing the calibration procedure of the Gurson model and making a rapid evaluation in terms of the Crack Driving Force (CDF) for defective girth weld. The tool allows also a quick and efficient model preparation, full FE analysis and post-processing, with saving of engineering hours.
Subsea Pipeline Lateral Buckling Design: Strain Concentration or Strain Reduction Factors
Authors: Liu M. 
Published: October 2017

Strain based design is normally applied for HPHT pipelines when the conventional stress based method becomes impractical. In addition to a design safety factor, a strain concentration factor is typically incorporated in the lateral buckling assessment to account for non-uniform stiffness or plastic bending moment due to geometry and material strength mismatch between adjacent pipe joints. Increased strain concentration can compromise pipeline low cycle fatigue and lateral buckling capacity, leading to an early onset of local buckling failure. In this paper, the philosophy of local buckling mitigation using the strain concentration factor is examined. The local buckling behaviour is evaluated in relation to strain concentration. Global strain reduction and evolution against buckling is analysed with respect to varying joint mismatch level derived according to a structural reliability analysis.
The concept of a strain reduction factor due to mismatch is developed and proposed based on the global strain capacity reduction with reference to the uniform configuration. It is demonstrated that the strain reduction factor is a unique characteristic parameter. As opposed to strain concentrations it is an invariant insensitive to evaluation methods and the design strain demand level, hence more representative as a limiting design metric to maintain the safety margin. The use of the strain reduction factor is thus put forward in strain based lateral buckling design as an alternative to using the strain concentration factor. The method for obtaining the strain reduction factor and its application is developed. The rationale for its introduction is outlined and some of its benefits are established. The discernible difference and scenarios for application of either factors are discussed, including low and high cycle fatigue, linearity and stress concentration (SNCF from SCF for welds), ECA and lateral buckling. Additional causal factors giving rise to mismatch such as pipe schedule transition and buckler arrestor are also discussed. Iterations of FE analyses are performed for a pipe-in-pipe configuration in a case study.
Simulating Riser VIV in Current and Waves Using an Empirical Time Domain Model
Authors: Thorsen Mats J. , Sævik Svein 
Published: October 2017

The theoretical background of an empirical model for time domain simulation of VIV is reviewed. This model allows the surrounding flow to be time varying, which is in contrast to the traditional frequency domain tools. The hydrodynamic load model consists of Morison’s equation plus an additional term representing the oscillating effect of vortex shedding. The magnitude of the vortex shedding force is given by a dimensionless coefficient, and this force is assumed to act perpendicular to the relative velocity between the cylinder and the fluid. The time variability of the vortex shedding force is described by a synchronization model, which captures how the instantaneous frequency reacts to cylinder motion.
The parameters in the time domain load model are calibrated against a commonly used frequency domain VIV analysis tool, VIVANA. To do this, a finite element model of a vertical tensioned riser is established, and the structure is exposed to a linearly sheared flow. Key results such as cross-flow displacements along the riser, frequency content, r.m.s. of bending stresses and mean in-line displacements are compared, and it is shown that the frequency and time domain methods are close to equivalent in this simple case with stationary flow.
Finally, the time domain model is utilized to study VIV of a riser subjected to regular waves. The characteristics of wave induced VIV are discussed in light of the simulation results. It is seen that VIV is excited in the zone close to the surface, and the energy is transported downwards as traveling waves. The vibrations typically build up as the horizontal water particle velocity is high, and die out as the velocity decreases. The effect of varying the wave amplitude and period is investigated, and it is found that the dominating frequency, mode and r.m.s. stresses increase together with the wave height. The effect of the wave period is however more complicated. For example, reducing the wave period increases the dominating mode but decreases the displacements. Hence the stress may increase or decrease, depending on which of these effects are strongest.
Validation of Open-Source SPH Code DualSPHysics for Numerical Simulations of Water Entry and Exit of a Rigid Body
Authors: Buruchenko Sergei K. , Canelas Ricardo B. 
Published: October 2017

Water entry and exit of a body is an important topic in naval hydrodynamics as these phenomena play relevant roles both for offshore structures and vessels. Water entry and exit events are intrinsically transient and represent intense topological changes in the system, with large amounts of momentum exchange between phases. At its onset, they can be characterized by highly localized, both in space and time, loads on the vessel, influencing both the local structural safety of the structure and the global loads acting on it.
The DualSPHysics code is proposed as a numerical tool for the simulation of fluid and floating object interaction. The numerical model is based on a Smoothed Particle Hydrodynamics discretization of the Navier-Stokes equations and Newton’s equations for rigid body dynamics. This paper examines the water impact, fluid motions, and movement of objects in the conventional case studies of object entry and exit from still water. A two dimensional body drop analysis was carried out demonstrating acceptable agreement of the movement of the object with published experimental and numerical results. The velocity field of the fluid is also captured and analyzed. Simulations for water entry and exit of a buoyant and neutral density cylinder compares well with previous experimental, numerical, and empirical studies in penetration, free surface evolution and object kinematics. These results provide a good foundation to evaluate the accuracy and stability of the DualSPHysics implementation for modeling the interaction between free surface flow and free moving floating objects.
Test to Determine Hydrodynamic Interaction Between Drilling Riser, Drill String and Mud
Authors: Li Songcheng , Campbell Mike , Russo Massimiliano , Katla Erling 
Published: October 2017

Drilling riser damping can have a significant effect on the dynamic response of the drilling system, especially the fatigue response of the wellhead and conductor system. The presence of any drilling riser damping helps to diminish the transfer of riser motions into the wellhead system, which can improve any wellhead fatigue issues.
One of the little studied contributors to the system damping is the hydrodynamic damping effect of the interaction between the drill pipe and drilling fluid inside the riser. As part of the ongoing Structural Well Integrity Joint Industry Project (JIP), finite element analysis (FEA) with a wide range of drag and inertia coefficients is conducted to simulate the mud drag and inertia on the drill string and the riser. These sensitivity studies demonstrate that the mud drag and inertia on the drill string could be one of the key driving factors in riser system damping. To verify the FEA work, the Structural Well Integrity JIP conducted a laboratory test to determine the drag coefficient and added mass coefficient of drill pipe inside a marine drilling riser with and without flowing mud and water in the riser annulus.
In this paper, the test setup and the test matrix are introduced, and the methodology for determining drag coefficient and added mass coefficient are explained. The test results are also presented and compared with published test data for open water.