bluuebunny/crossref_metadata_2025_split huggingface dataset:
Protected against all odds? A mixed‐methods study on the risk of welfare sanctions for immigrants in Germany
Authors: Gschwind Lutz , Ratzmann Nora , Beste Jonas 
Published: December 2021

AbstractSanctions are payment cuts that case managers implement in order to discipline welfare recipients. Previous research suggests that immigrants face a particularly high risk to receive such reductions, primarily due to the prevalence of stereotyping in street‐level bureaucracy. The study contributes to this literature with help of a triangulation between in‐depth interviews, survey data and administrative records for the case of the German social assistance system. Our findings indicate that immigrants tend to be sanctioned at a lower rate than other benefit recipients in this context, especially if they arrived at the country only recently on grounds of international protection. This finding can be explained by the importance of reciprocity and control in the country's ‘Bismarckian’ welfare state. Our qualitative data shows that case managers exert a considerable level of agency over the implementation process. This discretion is, on the one hand, used to discipline benefit recipients who are perceived as having contributed little to the welfare system as a whole through taxes and social insurance contributions. Those who are considered to have limited control over their labour market position, on the other hand, are given a certain degree of leeway. We therefore conclude, against the background of the current street‐level bureaucracy literature, that immigration can also act as a deservingness cue in means‐tested social assistance, given that the benefit system is embedded into a welfare regime in which labour market participation, work‐testing and social insurance contributions are the dominating principles of eligibility.
Towards a sensible bifurcationism (concerning what grounds thought about particulars)
Authors: Pepp Jessica 
Published: December 2021

AbstractIn virtue of what are particular individuals or objects thought about? I call this thegrounding question. A consensus answer isbifurcationism: objects can be thought about in virtue of both satisfactional grounds—roughly, in virtue of their unique satisfaction of conditions that figure in a subject's thought—and non‐satisfactional grounds. Bifurcationism is a consensus view, but it comes in different flavours that correspond to different approaches to answering the grounding question. This paper draws on Saul Kripke's approach to linguistic reference in order to make recommendations about how to move toward a sensible bifurcationism concerning what grounds thought about particulars.
Bleeding outcomes of inpatients receiving therapeutic plasma exchange: A propensity‐matched analysis of the National Inpatient Sample
Authors: Soares Ferreira Júnior Alexandre , Boyle Stephen H. , Kuchibhatla Maragatha , Onwuemene Oluwatoyosi A. 
Published: December 2021

AbstractBackgroundAlthough therapeutic plasma exchange (TPE) is associated with hemostatic abnormalities, its impact on bleeding outcomes is unknown. Therefore, the main study objective was to determine bleeding outcomes of inpatients treated with TPE.Study Design and MethodsIn a cross‐sectional analysis of the National Inpatient Sample (NIS), discharges were identified with 10 common TPE‐treated conditions. A 1:3 propensity‐matched analysis of TPE‐ to non‐TPE‐treated discharges was performed. The primary outcome was major bleeding and secondary outcomes were packed red blood cell (PRBC) transfusion, mortality, disposition, hospital length of stay (LOS), and charges. Multivariable regression analyses were used to examine the association between TPE and study outcomes.ResultsThe study population was 15,964 discharges, of which 3991 were TPE‐ treated. The prevalence of major bleeding was low (5.4%). When compared to non‐TPE discharges, TPE had a significant and positive association with major bleeding (OR = 1.37, 95% CI: 1.16–1.63, p = .0003). TPE was also associated with PRBC transfusion (OR = 1.66, 95% CI: 1.42–1.94, p < .0001), in‐hospital mortality (OR = 1.45, 95% CI: 1.10–1.90, p = .0008), hospital length of stay (12.45 [95% CI: 11.95–12.97] vs. 7.38 [95% CI: 7.12–7.65] days, p < .0001) and total charges, ($125,123 [95% CI: $119,220–$131,317] vs. $61,953 [95% CI: $59,391–$64,625], p < .0001), and disposition to non‐self‐care (OR = 1.29, 95% CI: 1.19–1.39, p < .0001).DiscussionThe use of TPE in the inpatient setting is positively associated with bleeding; however, with low prevalence. Future studies should address risk factors that predispose patients to TPE‐associated bleeding.
Heat Transfer of Turbulent Gaseous Flow in Microtubes With Constant Wall Temperature
Authors: Hong Chungpyo , Asako Yutaka , Faghri Mohammad , Ueno Ichiro 
Published: December 2021

Abstract
In this paper, we report on experimental results to measure the total temperature of nitrogen gas at the inlet and outlet of microtubes with constant wall temperature and to quantitatively determine the heat transfer rates. Experiments were conducted with nitrogen gas flowing in a stainless steel microtube with a diameter of 524 μm and a copper microtube with a diameter of 537 μm. The temperature differences between the inlet and the wall were maintained at 3, 5, and 10 K by circulating water around the inlet and the wall. The stagnation pressures were also controlled so that the flow, with atmospheric back pressure, could reach Reynolds numbers as high as 26,000. To measure the total temperature, a polystyrene tube with a thermally insulated exterior wall containing six plastic baffles was attached to the outlet. Heat transfer rates were obtained from the gas enthalpy difference by using the pressures and the total temperatures measured at the inlet and outlet. Heat transfer rates were also compared with those obtained from the ideal gas enthalpy using the measured total temperatures and from the Nusselt number of incompressible flows. It was found that the measured total temperature at the microtube outlet was higher than the wall temperature. Also, the heat transfer rates calculated from the total temperature difference were higher than the values obtained from the incompressible flow theory.
Planar Compliance Realization With Two 3-Joint Serial Mechanisms
Authors: Huang Shuguang , Schimmels Joseph M. 
Published: December 2021

Abstract
In this paper, the realization of any specified planar compliance with two 3R serial elastic mechanisms is addressed. Using the concept of dual elastic mechanisms, it is shown that the realization of a compliant behavior with two serial mechanisms connected in parallel is equivalent to its realization with a 6-spring fully parallel mechanism. Since the spring axes of a 6-spring parallel mechanism indicate the geometry of a dual 3R serial mechanism, a new synthesis procedure for the realization of a stiffness matrix with a 6-spring parallel mechanism is first developed. Then, this result is extended to a geometric construction-based synthesis procedure for two 3-joint serial mechanisms.
Effective Clearance and Differential Gapping Impact on Seal Flutter Modeling and Validation
Authors: Corral Roque , Greco Michele , Vega Almudena 
Published: December 2021

Abstract
This paper presents an update of the model derived by Corral and Vega (2018, “Conceptual Flutter Analysis of Labyrinth Seal Using Analytical Models. Part I—Theoretical Support,” ASME J. Turbomach., 140(12), p. 121006) for labyrinth seal flutter stability, providing a method of accounting for the effect of dissimilar gaps. The original Corral and Vega (CV) model was intended as a conceptual model for understanding the effect of different geometric parameters on the seal stability comprehensively, providing qualitative trends for seal flutter stability. However, the quantitative evaluation of seal flutter and the comparison of the CV model with detailed unsteady numerical simulations or experimental data require including additional physics. The kinetic energy generated in the inlet gap is not dissipated entirely in the inter-fin cavity of straight-through labyrinth seals, and part is recovered in the downstream knife. This mechanism needs to be retained in the seal flutter model. It is concluded that when the theoretical gaps are identical, the impact of the recovery factor on the seal stability can be high. The sensitivity of the seal stability to large changes in the outlet to inlet gap ratio is high as well. It is concluded that fin variations due to rubbing or wearing inducing inlet gaps more open than the exit gaps lead to an additional loss of stability concerning the case of identical gaps. The agreement between the updated model and 3D linearized Navier–Stokes simulations is excellent when the model is informed with data coming from steady Reynolds-averaged Navier–Stokes simulations of the seal.
Combined Cycle Powerplant Cost Sensitivity Analysis
Authors: Nanadagopal Pugalenthi , Pandey Animesh , More Manjunath , Kamboj Pertik 
Published: December 2021

Abstract
In Gas turbine-based combined cycle power plant market, the customer conducts an economic evaluation of competitive products to decide their buying option. There are different methods to calculate the economics of a power plant like Levelized cost of electricity (LCOE), Net present value (NPV) and payback period.
LCOE methodology is commonly used for lifecycle cost analyses for combine cycle power plant that covers cost details of the plant and plant performance over the complete lifetime of a power plant from construction to retiring. Typically, it includes a combine cycle power plant ownership costs (Total plant cost and operating & maintenance cost) and combine cycle power output and efficiency. This LCOE method is helpful to compare power generation system that use similar technologies.
This paper encompasses the LCOE calculation method, assumptions & approach to analyze the impact of key parameters of the electrical generation cost. They key parameters includes combine cycle output, combine cycle efficiency, fuel cost, annual operating hours, capital charge factor, annual operating hours, power plant life, discount rate, nominal escalation rate, operating & maintenance cost. This paper analyses result will provide insights to the customer & Gas turbine-based OEM (Own Equipment Manufacturing) companies to focus on different area/parameters to reduce the unit cost of generating electricity.
Experimental and Modeling Studies on the Stress Relaxation Behaviour of Ti-6Al-4V Alloy
Authors: Prasad Kali , Hariharan Krishnaswamy , K. Banerjee Dilip 
Published: December 2021

Abstract
The transient mechanical behavior of materials during stress relaxation has evoked interest in manufacturing applications because of the effect of stress relaxation on formability enhancement. However, most of the previous studies have focused on advanced high strength steels and aluminum alloys. Limited transient stress relaxation studies have been conducted on titanium alloys in order to understand the influence of stress relaxation on forming behavior. Titanium alloys are widely used in aerospace components because of their high strength to weight ratios and excellent fatigue strengths. However, room temperature formability of Ti alloys is an important concern, which restricts their widespread use in various applications. To address these challenges, the present study is aimed to understand the role of transient stress relaxation on formability of Ti alloys. Toward this end, stress relaxation of a dual phase titanium alloy (Ti-6Al-4V) has been investigated experimentally. Stress relaxation tests were performed by interrupting uniaxial tensile tests in the uniform deformation regime for a pre-defined strain and hold time after which tests were continued monotonically until fracture. Single step, room temperature stress relaxation experiments were performed systematically to study the effect of hold time, pre-strain, and strain rate on mechanical properties. The stress relaxation phenomenon was found to contribute positively to the ductility improvement. The mechanisms responsible for enhancing the formability are discussed. The experimentally obtained stress vs. time data were analyzed using a advanced constitutive model for stress relaxation available in literature.
Comprehensive Review & Enhancements on Probe Substitution Techniques for Faulty Steady State Inlet Pressure Distortion Data
Authors: Rajendrakumar Mithilesh , Vyas Manu , Deshpande Prashant , Balasubramanian Bommaian , Shepherd Kevin 
Published: December 2021

Abstract
When a gas-turbine engine is in operation, inlet-generated total-pressure distortion can have a detrimental effect on engine’s stability and performance. During the product development life cycle, on-ground wind tunnel tests and in-flight tests are performed to estimate the inlet distortion characteristics. Extensive measures are taken in the preparation and execution of inlet distortion tests. The data pertaining to spatial inlet distortion is recorded using an array of high-response total-pressure probes. The pressure probes are usually arranged in rake and ring arrays as per AIR1419. The data from these probes is used by propulsion system designers to address the effects of inlet distortion on stability and performance, particularly the engine’s sensitivity to inlet distortion. In some instances, the probes can produce inaccurate measurements or no measurements at all, due to a variety of reasons. This may result in a time consuming and costly process of repeating the test. To avoid this, the inaccurate or invalid measurements can be substituted using a variety of statistical techniques during test data post-processing. This paper discusses the results of different interpolation techniques to substitute invalid steady-state total-pressure measurements, evaluated in the context of classical distortion profile data available in AIR1419. The techniques include 1D linear interpolation using only probes data from adjacent rings, 1D linear interpolation using only probes data from adjacent rakes, and bilinear interpolation using probes data from adjacent rings and rakes. Furthermore, the paper evaluates a bilinear interpolation technique with optimal weights obtained from linear regression, that enhances the estimation of invalid pressure values.
Influence of Degradation, Fuel Cost and Electricity Price Factors on Combine Cycle Power Plant Cost Analysis
Authors: Nanadagopal Pugalenthi , Duerr Matthias , Fahrendorf Ole , Haid Dan , Paprotna Hubert 
Published: December 2021

Abstract
Gas turbine-based combine cycle (GT-CC) economic evaluation is very important to bring together own equipment manufacturing companies (OEM’s) and power plant owners. The fuel cost & cost of electricity play the major role in economic evaluation which drives the decision during the bidding.
The first portion of this paper encompasses the different cost analysis methods like Net Present Value (NPV), Internal Rate of Return (IRR), Levelized Cost of Electricity (LCOE) and Pay Back Period (PBP) for different fuel costs and electricity prices.
The second portion of the paper covers the delta cost benefits due to improvement in the combined cycle degradation GT-CC operators or customers are looking for the opportunities to control and minimize the degradation of the gas turbine power plant which directly impact the profitability. The customer or operator always monitor the plant performance to understand the life cost impact on performance degradation.
This paper will help the customers & GT-CC OEM companies to focus on different area to reduce the unit cost of generating electricity, decide to move forward with the project during the proposal and improve the business at various regions based on fuel cost and global geographical political situations. Also, the reader can digest the benefits of improved degradation curve over the normal curve.
Effect of Corrosion Pit on the Structural Characteristics of Foil Journal Bearings
Authors: Mourya Vishal , Bhore Skylab P. 
Published: December 2021

Abstract
Due to corrosive environment, material loss in a localized area leads to formation of a corrosion pit. It diminishes the structural integrity and performance of product. To predict and analyze the effect of corrosion pit on the performance of gas foil bearings (GFBs), FEM analysis of bump-type GFBs is carried out. The effect of corrosion pit is investigated for three different shapes: circular, square and triangular. In this study, the FEM analysis of bump-type GFBs is performed in ANSYS software. Firstly, the influence of a corrosion pit is analyzed for various shapes under different pressure loading. These results show that the presence of a corrosion pit developed high-stress crack intensity, which can result in crack initiation in foil bearings. As pressure loading increased, the stress crack intensity in foil bearings increased. Among different pit shapes, the circular pit shape induces the maximum stress crack intensity in foil bearings, which shows that the crack initiation in foil bearings is observed for a circular pit. Then, the influence of a corrosion pit on the structural stiffness of foil bearings is evaluated for various foil materials under different friction coefficients. These results show that the influence of friction coefficient in foil bearings is increased within the presence of a corrosion pit.
Sensitivity of the Spool Rate on the Dynamic Response of the System
Authors: Das Arnab , Iyappan Praveen , Chinthapally Srinivas , Kumar Avinash 
Published: December 2021

Abstract
In rotodynamic systems, the rotor is spooled up from zero speed to its operating speed during the engine start. One of the considerations in design of rotating systems is the placement of rotor critical speed. It is vital to ensure that the rotor critical speeds are not close to the engine operating speed. However, it is not always possible to isolate all the frequencies above the operating speed. So, during the engine start to full speed, rotor system does travel through the mode. Therefore, to avoid a large system response, the rotor is spooled up quickly through the critical speed. In addition to the rotor critical speeds, the natural frequencies of the static structures may also get excited during the rotor spool up and spool down. The static structure response is one of the important considerations in designing a system for dynamic loading condition. It has been observed that the rotor spool rate affects the static structure response. This paper focuses on effect on system’s response under various spool rate. It has also been shown that the natural frequency of the system and damping in the system are two of the major factors towards sensitivity of system response with spool rate. Additionally, it has been observed that the presence of non-linearities shifts the peak response away from the natural frequency depending on the spool rate and spool direction.
Machine Learning Based Classification Model for Predicting Cyclic Failure in Radially Cooled Gas Turbine Blades
Authors: Shrivastava Rishabh , Kapoor Ankush , Kaushal Stuti , Yadav Amit , Vodnala Pavankumar 
Published: December 2021

Abstract
Gas turbine blades and vanes face very severe operating conditions - high temperature and pressure which necessitates the creation of complex cooling and component designs, resulting in high computational cost. The ability to predict cyclic failure in these components is therefore a critical activity that has been historically performed using 3D commercial finite element (FE) codes for baseload conditions. However, these codes take substantial time and resources which restricts their application in failure prediction at variable operating conditions. Newer data-driven techniques such as machine learning (ML) provide a valuable tool that can be utilized to predict the occurrence of cyclic failure for these conditions with minimal time and resource requirement.
In this paper, a machine learning based surrogate model is developed to predict the cyclic failure of a radially cooled turbine blade. The features used as input to machine learning model are turbine inlet temperature, coolant inlet temperature, hot gas mass flow rate, cooling air mass flow rate and blade materials. The output for the model is a binary variable depicting the incident of component failure. 70% of the FE data points are used to train the ML model while the remaining are used for testing. A comparative study between Logistic Regression, Random Forest, K-nearest neighbor, and Support Vector Machine (SVM) was performed to select the most accurate algorithm for the classification model. Finally, the results show that the Random Forest and SVM algorithms predicts failure with the highest f-1 score of 0.92. The model also demonstrates that Turbine Inlet temperature has the highest importance amongst the input features followed by blade material. Additionally, this methodology offers a tremendous advantage for failure prediction by reducing analysis time from multiple hours to a few seconds, rendering this technique especially beneficial for time sensitive business decisions in the gas turbine industry.
Dynamic Modelling and Free Vibration Characteristics Analysis of Rotating Beams
Authors: Sachin D. , Reddy Mallikarjuna 
Published: December 2021

Abstract
Turbine blades are ideally modeled as cantilever beams on a disc rotating at a constant angular velocity. A study is made to understand the dynamic relationships between a rotating cantilever beam and various factors like hub radius, rotation speed, and slenderness ratio in in-plane vibration (Chordwise motion) and out-of-plane vibration (Flapwise motion). Hub is assumed to be rigid in the study. Using Hamilton’s principle, governing differential equations of movement for free vibration analysis of Euler-Bernoulli beam (EB) and Timoshenko (TB) beam under rotation are derived. The effects of the Gyroscopic couple are taken into account in the equations. The beam model is discretized using the Finite element approach. Derived differential equations are transformed into dimensionless quantities in which dimensionless parameters are identified. Under rotation, it is observed that the natural frequencies increase with the increase in rotational speed for both flapwise and chordwise motions of the beam. An interesting phenomenon is observed in the chordwise motion results, where Natural frequencies veer off at certain rotational speeds and certain modes. Slenderness ratios also influence this phenomenon, which shifts the veer-off region and the tuned angular frequency. Numerical results are obtained for different rotational speeds with various hub radius ratios, and it was observed that hub radius directly influences the natural frequencies of the rotating uniform cantilever beam. A thorough study on the influence of the slenderness ratio showed that, for lower slenderness ratio, frequency veering region occurs at the fundamental natural frequency, but for higher slenderness ratios’ there is a shift in frequency veering region for higher modes.
Coupled Thermal-Structural Analysis of Generator For sCO2 Turbomachinery
Authors: Guntanur Ramesha , Patel Ashutosh , Biradar Vijay , Kumar Pramod 
Published: December 2021

Abstract
This paper presents the coupled thermal and structural analysis of the rotating components of the generator using ABAQUS finite element solver. The interference between shaft and rotor is optimized to have a positive contact pressure and also minimize the stresses in the laminate at all operating speeds. Thermal analysis is performed to simulate the temperature distribution arising from the heat losses of generator. The flow path of the coolant is designed through the shaft to minimise the temperature rise of the generator. The resulting changes in the contact pressure between laminated disc and shaft is computed using sequentially coupled thermal and structural analysis. The thermal stresses of rotor are computed estimated and the design is optimized for transmitting torque at different operating speeds.