Miracle-dz/UniFAR-FTUs huggingface dataset:
Experimental and Numerical Fatigue Life Study of Inner Liner Material in Rocket Combustion Chambers

The paper on hand presents the experimental and numerical results of a fatigue life study conducted with Cu-HCP being used as the inner liner material for regeneratively cooled cryogenic rocket combustion chambers. This material is suitable for combustion chambers which are prone to moderate levels of hot-gas surface temperature and wall heat flux. The experimental part of this study uses Thermomechanical Fatigue (TMF) panels made of the high-conductivity Cu-HCP that were cyclically tested to failure at the TMF test bench at DLR Lampoldshausen Institute of Space Propulsion. A TMF panel represents a small section of a regeneratively cooled rocket combustion chamber. It typically consists of 7 cooling channels. The coolant being used is supercritical nitrogen instead of hydrogen or methane due to safety and cost concerns. The TMF test bench also incorporates a high power diode laser radiating onto the TMF panel surface. This provides realistic amounts of heat flux and surface temperature. The laser is cyclically powered on and off to represent the multiple load cycles that liquid rocket engines have to endure particularly in reusable rocket engines. The setup of the TMF test bench provides data regarding the pure mechanical behavior of the material without the influences of any combustion or chemicals. Furthermore, heat flux, surface temperature and mass flow rate can be easily determined, hence providing precise input data for a numerical simulation and validation. The test conditions of the TMF panel were a heat flux of $\dot{\mathrm{q}}=24.25$ MW / m2 and a maximum surface temperature of $\mathrm{T}_{\mathrm{s}}=800$ K. For numerical modeling of the experiment, ANSYS Mechanical was used. Herein the nonlinear material models implemented within the software package were used. In particular, the kinematic hardening model according to Chaboche, the isotropic hardening and softening model after Voce, Norton's creep fatigue law and the strain rate dependency model according to Peirce were used. The mechanical material parameters for the numerical model were determined by means of an extensive test series including low cycle fatigue (LCF) and tensile tests with uni-axial specimen covering a range of temperatures starting from cryogenic conditions at 77 K towards 1000 K. The numerical fatigue life is estimated by a post processing tool.
Ellipsoidal load‐domain shakedown analysis with von Mises yield criterion: A robust optimization approach

The static formulation of elastic shakedown analysis, based upon Melan's lower‐bound theorem, can essentially be viewed as a robust optimization problem. This paper discusses an advantage that is enjoyed by taking this perspective. Specifically, we assume the von Mises yield criterion and an ellipsoidal load domain. In this setting, the shakedown analysis problem, which is viewed as robust second‐order cone programming, can be recast as semidefinite programming. Copyright © 2016 John Wiley & Sons, Ltd.
Demonstration on Warpage Estimation Approach Utilized in Fan-Out Panel-Level Packaging Enabled by Multi-Scale Process-Oriented Simulation

Despite of the enlarged area of the fan-out panel-level packaging (FO-PLP), the process-induced warpage may cause a serious yielding problem in the subsequent process and assembly for the package. The finite element analysis (FEA) is proposed in many researches to overcome the problem of time cost. The important issue is the discontinuous model and warpage after the sawing process from panel to strip, and strip to unit package for FEA. In this research, a redistribution layer (RDL) first FO-PLP is presented with integrated multiple scale of package model in FEA analysis. The equivalent materials method and the equivalent stress-free temperature in the process-orientation simulation is applied on RDL. The chemical shrinkage of molding underfill is also concerned. The multipoint constraint method is applied on the boundary of multiple scale model to solve the multiple scale problem with panel and strip. The warpage error between the simulation and experiment are below 10 %.
The Extinction-to-Backscatter Ratio of Tropospheric Aerosol: A Numerical Study

Abstract An adequate estimation of the aerosol extinction-to-backscatter ratio S is important for solving the underdetermined single scattering lidar equation and for investigating the climate impact of aerosols. In this study, the extinction-to-backscatter ratios for the Nd:YAG wavelengths are calculated for continental, maritime, and desert aerosols; the corresponding aerosol components are varied within the expected natural variabilities of the particle number mixing ratios. For continental aerosol, S increases with the relative humidity f from 40 to 80 sr. For maritime aerosol, the extinction-to-backscatter ratios lie between 15 and 30 sr for 355 and 532 nm and between 25 and 50 sr for 1064 nm. The desert aerosol exhibits a weak dependence of S on f and ranges between 42 and 48 sr for 355 nm and between 17 and 25 sr for 532 and 1064 nm. For practical applications, the calculated values of S are fitted by a power series expansion with respect to their dependence on f.
Vortex and Strain Skeletons in

We present an approach to analyze mixing in flow fields by extracting vortex and strain features as extremal structures of derived scalar quantities that satisfy a duality property: They indicate vortical as well as high-strain (saddle-type) regions. Specifically, we consider the Okubo-Weiss criterion and the recently introduced MZ criterion. Although the first is derived from a purely Eulerian framework, the latter is based on Lagrangian considerations. In both cases, high values indicate vortex activity, whereas low values indicate regions of high strain. By considering the extremal features of those quantities, we define the notions of a vortex and a strain skeleton in a hierarchical manner: The collection of maximal zero-dimensional, one-dimensional, and 2D structures assemble the vortex skeleton; the minimal structures identify the strain skeleton. We extract those features using scalar field topology and apply our method to a number of steady and unsteady 3D flow fields.
Elements of Cosmological Ination

We present an elementary study of the phenomena of ination (exponential expansion driven by a negative-pressure vacuum energy density) which occurs during the evolution of the early universe around 10 36 seconds after the original singularity at the Big Bang. Ination means that spacetime is almost de Sitter and it is at the origin of the large scale structure we observe today. In this dissertation we outline how ination solves the famous cosmological puzzles of horizon and atness. We pay in particular special attention to the physics of how the small quantum uctuations during the inationary phase give rise to temperature anisotropies observed in the cosmic microwave background (CMB) radiation. As we will discuss inationary models which agree with the observations fall in the class of a single scalar eld, adiabatic, Gaussian and scale invariant theories.
A new species of Cerozodus and new records of Asilinae and Ommatiinae (Diptera: Asilidae) from Tocantins, Brazil

ABSTRACT This paper represents the first study on Asilidae for the state of Tocantins, Brazil. Here, we describe a new species of Cerozodus Bigot, 1857 and second record for the North Region of Brazil, as well as supply the first record of occurrence of five genera and 12 species of Asilinae and Ommatiinae in Tocantins. Additionally, we provide illustrations and comments for all new records of species and an updated list of Asilidae for the state.
Ewes with higher embryo survival rear lambs that grow faster

Abstract A key economic driver of a meat producing sheep flock is the total kilograms of lamb liveweight at weaning per ewe exposed to the ram. Optimization of key reproductive steps is required to achieve peak performance of a sheep flock. The goal of this paper was to use more than 56,000 records from a commercial flock to investigate the key reproductive steps affecting flock reproductive performance. We also applied a maximum-likelihood based technique to predict the embryo survival and ovulation rate for daughters of individual sires based on measurements of the number of fetuses at midpregnancy (detected by ultrasound-scanning). The model was used to determine how changes in premating liveweight, age, predicted ovulation rate, embryo survival, number of fetuses at midpregnancy, lamb survival, and lamb growth rate affect the total lamb liveweight at weaning per ewe exposed to the ram in the flock. The data from the commercial flock was also used to investigate the role of ewe age and premating liveweight on each reproductive step. Sensitivity analyses were performed to identify the key reproductive steps affecting flock reproductive performance. The elasticity for embryo survival was 80% of that for lamb survival. There was also significant between sire variance in the estimates of ovulation rate and embryo survival. The reproductive performance of daughters of sires with high (top 50%) and low (bottom 50%) embryo survival was investigated. Embryo survival was 0.88 in the high group and 0.82 in the low group (a 6% reduction in embryo survival). The expected total weight of lambs weaned per ewe exposed to the ram was 42 kg in the high embryo survival group and 37 kg in the low embryo survival group (a 12% reduction in the total weight of lambs weaned per ewe exposed to the ram). The proportion of twin litters was 70% in the high group and 60% in the low group, highlighting the potential importance of embryo survival for the rate of twinning in flocks with ovulation rates greater than two ova. Although lamb survival was similar between the high and low embryo survival groups, lamb growth was reduced by 10% in the low embryo survival group for the same litter size (P < 0.001). This novel positive phenotypic association between embryo survival and lamb growth rate can potentially be exploited to improve flock performance.
Development of an Efficient Cardiac Auscultation System Using Proper Denoising Techniques

Heart auscultation is a primary and cost-effective form of clinical examination of the patient. PCG signal is used as a diagnostic test for evaluating the status of the heart and it helps in identifying related diseases. There are several limitations and practical problems in the human auditory system when it comes to phonocardiogram (PCG) signal analysis in a clinical environment, despite the cognitive skills and expertise of the medical examiner. Thus, the assessments provided by cardiac auscultation are subjective and sometimes provide an inaccurate diagnosis. The objective of this research is to develop an efficient heart auscultation system by implementing necessary pre-processing and suitable filtering techniques. The problem of controlling the noise level has been one of the research topics over the years. The various filters used are IIR Butterworth and Chebyshev digital filters, FIR filters, LMS filter, Wiener filter, Wavelet transform based filter and cascading of these filters were also done and the filter which gives the highest value of SNR and good tone audibility score is chosen as the most efficient filter for noise removal. Based on the performance comparison of various filtering technique and calculation of heart rate, an efficient heart auscultation system is developed to assist medical practitioners in PCG signal analysis.
The Impact of Household Asset Allocation on the Heterogeneity of Residents' Consumption Based on CFPS Micro Data

In response to the impact of household asset allocation on residents' consumption heterogeneity, this article first uses the China Family Panel Studies (CFPS) to conduct preliminary analysis and statistics, and selects some control variables. Secondly, the instrumental variable method is used to study the total consumer expenditure of residents and determine the feasibility of controlling variables. Finally, based on this, the instrumental variable method is used to study the secondary and tertiary indicators of asset allocation and the secondary indicators of consumer expenditure, and the model is tested to determine the impact of household asset allocation types on residents' heterogeneous consumption. The research draws the following conclusions: (1) The average marginal utility of household physical asset holdings on consumption is slightly greater than the marginal utility of financial assets. (2) Household cash and deposit holdings have a more obvious marginal utility on consumption than their holdings of financial products. (3) The positive impact of the total purchase price of a family car on medical, entertainment, and home expenses is significantly greater than its impact on clothing, food, housing, and transportation expenses.
Rapid energy release in inflatable soft actuators through reversible bond breaking

Inflatable actuators are regularly used to induce large complex deformations in soft robotic systems. Their actuation speed is typically low, as it takes time for fluids to be pushed through narrow pressure supply tubes. To overcome this limitation, we take inspiration from nature and create actuators that can suddenly release build up elastic energy, by means of breaking a physical bond. Where in nature these ruptures are irreversible, here we use the reversible adhesion of a suction cup to accomplish the same behavior. First, we show that the released elastic energy originates from an adiabatic transition from the constrained to the free inflation curve of the actuator. Next, we numerically analyse this process and give design considerations for maximizing energy release. Lastly, we build a prototype actuator that displays this type of energy release and demonstrate that it can be used for jumping.
An Auto-ANN for EMG Classification for the Motion Recognition of the Human Hand

Electromyography (EMG) signals can contain useful information related to the user's intentions. The usage of these signals for motion recognition has been widely studied in the last few years and can be used to control exoskeletons for rehabilitation or assistance. The aim of this study is to identify different motions using EMG signals, by using an automatic Artificial Neural Network (ANN). We apply our proposed architecture to the Ninapro DB2 dataset. This dataset contains information about 40 different subjects and 49 different motions divided into three types of exercises. The dataset is divided into 70% training, 15% validation, and 15% testing. The accuracy found for the model is 81.18% for exercise of type B, 77.76% for exercise of type C, and 91.70% for exercise of type D, over 10 different subjects.
Augmenting Seasoned English Language Teachers’ ICT Skills through a Service-Learning Activity-based TPACK

Due to the emergence of ICT in ELT sector, seasoned English teachers find it resistant to such a shift despite having a positive attitude towards its use. This quasi-experimental study aimed to examine the extent to which seasoned English language teachers developed their ICT skills through a Service-Learning Activity (SLA). Using a one-group pre- and post-test design, this study collected the data through a modified Needs Assessment Survey (NAS) distributed to fourteen purposively selected participants. It was administered to examine what professional ICT development would greatly benefit them. The data were analyzed using descriptive statistics and themes according to the Service-Learning Activity (SLA) topics. A Post Evaluation Survey (PES) was administered, and its result was compared to the initial test. The results showed that the seasoned teachers gained significant learning gains in terms of (1) sharing of knowledge from other teachers; (2) being encouraged to use ICT tools; (3) training opportunities; (4) working with other colleagues; and 5) attending professional workshops which include SLA. However, this study unveiled that the English teachers had no significant difference in perceptions regarding the roles of computers in teaching before and after the intervention. Limitations and recommendations for future studies were discussed
Reduced rank regressions and the Poincare separation theorem

This paper presents a synopsis of approaches for solving the reduced rank re- gression problem. In particular, the literature mentions the least generalised vari- ance ratio (LGVR) approach, the Eckart-Young (EY) theorem, Poincare's separa- tion theorem (PST) and Fan's inequality, without paying much attention to the interrelationship between these results. See, for instance, Johansen (1988), Eckart & Young (1936), Rao (1979) and Robinson (1974), respectively. Thus, this paper demonstrates that the LGVR result, the EY theorem and Fan's inequality may all be derived on the basis of the PST, arguing that the latter is the common root and the unifying theme of this literature. Proofs not available in the literature are provided and heuristic arguments to clarify existing derivations are given.
Empowerment not racialised segregation

Abstract The aim of this paper is to investigate the ‘equalising effect of schools’ in general and two concrete interventions that have been carried out recently in Sweden in particular. The first of these interventions is the closing down of schools in deprived neighbourhoods and moving pupils to other schools. The second is ‘empowerment’ – i.e., creating an inclusive and supportive pedagogical school environment for students with working-class and immigrant backgrounds. As findings from previous Swedish studies regarding the first intervention show, an equalising effect will not be achieved without considering the ‘school climate’ of mixed schools. The findings from this case study of a school located in a deprived suburb of Stockholm County indicate that even schools in these areas are able to equalise educational opportunities through building an alliance between students, parents and community activists on the one hand and bi-class and bi-cultural brokers like teachers and social workers on the other.
Temperature Control System for Fabrication of W-microprobes

Electrochemical etching is one of the most popular methods to fabricate micro and nanoscale metal (usually tungsten) probes to be used in the fields of electrical characterization, scanning tunneling microscopy, scanning probe lithography, healthcare, etc. Temperature of the electrolyte is one of the key parameters that decide the diameter and profile of the probe tip. A rapid change in the temperature of electrolytes causes an unwanted profile and larger tip diameter of the probe. In this paper we report a simple and low-cost feedback-based temperature control system to maintain the temperature at a desired value. We demonstrate electrochemical etching of W wire using the developed (in-house) temperature control system and have fabricated micron scale sharp probe tips which are used for a novel scanning probe-based lithography technique - electrolithography.
A Novel Methodology to Predict Process-Induced Warpage in Advanced BEOL Interconnects

Process-induced warpage caused by high-density interconnects in the back-end of line (BEOL) structure, may affect the performance and the reliability of the product during the packaging process. In this paper, a BEOL structure is used to develop a process-oriented simulation methodology to optimize the design and predict warpage. To reduce simulation time and obtain accurate predictions, the equivalent material method and equivalent residual stress are used in our proposed method. The layer-by-layer warpage predictions matched the measurement data.
First report of Leishmania (Mundinia) martiniquensis in South American territory and confirmation of Leishbunyavirus infecting this parasite in a mare

BACKGROUND Epidemiological data related to leishmaniases or Leishmania infection in horses are scarce. However, studies carried out in different regions in the world showed equids parasitised by Leishmania braziliensis, L. infantum and L. martiniquensis. OBJECTIVES Identify the Leishmania species causing cutaneous leishmaniasis in a mare, living in Rio de Janeiro State (Brazil), and search the presence of Leishmania viruses in the isolated parasite. METHODS Isoenzymes and polymerase chain reaction (PCR) targeting ITSrDNA region followed by sequencing were conducted for typing the isolated parasite. A search for Leishmania virus infection was also performed. FINDINGS The mare presented skin nodules and ulcers in the left pinna caused by Leishmania spp. that was detected by culture and PCR. The parasite was identified as Leishmania (Mundinia) martiniquensis, infected by Leishbunyavirus (LBV), representing the first description of this species in South America. The animal travelled to different Brazilian regions, but not to outside the country. MAIN CONCLUSIONS The worldwide distribution of L. martiniquensis and its infection by LBV were confirmed in this study, indicating the autochthonous transmission cycle in Brazil. The clinical profile of the disease in the mare, showing fast spontaneous healing of cutaneous lesions, may indicate that skin lesions related to L. martiniquensis infection in horses might be underdiagnosed.
Current status and future directions of amyotrophic lateral sclerosis research in Africa: a perspective

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease with a global burden. Despite significant strides in ALS research, challenges facing ALS research in Africa are substantial. This paper discusses the current status and future directions of ALS research in Africa. Challenges and opportunities for ALS research in the region are highlighted, including limited funding and resources, the need for collaboration, and capacity building. Emerging technologies in ALS research in Africa are described, including telemedicine, neuroimaging, and genetic studies. Priorities for future ALS research in Africa are identified, including epidemiological studies, developing culturally appropriate diagnostic and management tools, and clinical trials of emerging treatments. Addressing these priorities will be critical to advancing ALS research and improving patient outcomes in Africa.
Shape and Tip Force Estimation of Concentric Tube Robots Based on Actuation Readings Alone

Recent advances on Concentric Tube Robots (CTRs) enable the construction and analysis of concentric combinations of precurved elastic tubes. These robots are very appropriate for performing Minimally Invasive Surgery (MIS) with a reduction in patient recovery time. In this work, we propose a kinetostatic model for CTRs based on the Geometric Variable-Strain (GVS) approach where the tubes' sliding motion, the distributed external forces along the tubes and concentrated external forces at the tip, are included. Our approach allows us to estimate the shape of CTRs and the tip forces using the displacements of the tubes and the insertion and rotation input forces and torques. Moreover, we propose a modification in the model, which eliminates completely the sliding friction among the tubes. This new approach opens a new way to use CTRs in surgical applications without the need of sensors along the tubes, but only actuation measurements. The simulation results demonstrate the effectiveness of the proposed approach.