Miracle-dz/UniFAR-FTUs huggingface dataset:
On channel estimation in cell‐free massive MIMO for spatially correlated channels with correlated shadowing under Rician fading

This work addresses channel estimation (CE) in the uplink phase for a cell‐free massive multiple‐input multiple‐output system operating under the time division duplex protocol. Considering that, channels are spatially correlated under the Rician fading model, where the investigated model is composed of two components: deterministic and nondeterministic, with the deterministic component describing the line‐of‐sight paths and the nondeterministic component describing the non‐line‐of‐sight paths. Additionally, we dealt with correlated shadow fading that represents the most realistic situation. On the other hand, this work introduces a dynamic cooperation cluster framework in which the user is not served with the whole network ( i.e., all access points [APs]) but only the APs that present the best channel conditions regarding that user. In other words, this work proposes partial CE for each user because only APs with the best channel conditions are allowed to compute channel estimates. Consequently, we proposed partial channel estimators that perform the CE process with low complexity, namely, a partial minimum mean square error estimator and a partial element‐wise minimum mean square error estimator. In addition, a simple pilot assignment technique is proposed in order to reduce interference signals so that each user experiences low interference from other users. Furthermore, the computational complexity required by each estimator is derived, where it is represented by the number of complex multiplications that each estimator requires in each consistency block. Theoretical and simulated results are provided, where the performance of each estimator is evaluated and analyzed using the normalized mean‐square error metric.
How to Create a Supportive Learning Environment in Mathematics Classes – An Example from a Norwegian Lower Secondary School Class

Mathematics is an important subject in school, however, many students find this subject very challenging. Some even dread mathematics as they do not master it and they may fear that their social status will be negatively influenced by this. It is therefore important that the teacher facilitates for creating a learning environment where students feel they can be open and supported when they struggle. The aim of the current study is to investigate how a five-step method including individual reflections and classroom discussions may facilitate for this type of supportive and motivating learning environment. The method builds on self-determination theory and theory of self-regulation. The five-step method was applied through a four-week long intervention in an eighth grade and focused on numbers and algebra. The students reflected on the following five questions: 1) What is important to learn in algebra and why? 2) What do you already master in relation to algebra? 3) What is difficult and prevents you from learning algebra? 4) What will you focus on improving the next few weeks? and 5) How exactly will you do this? The students filled in evaluation forms including both open and closed questions after the intervention (n = 15). The findings showed that six of the students agreed that the method helped them find out what was important to learn, seven followed the plans they made, five agreed that they had become better at dealing with challenges and three students felt more comfortable in class after the intervention.
Role of deployment-related mTBI and resilience in perceived participation limitations among Veterans

ABSTRACT Problems with social functioning are common following combat deployment, and these may be greater among individuals with a history of traumatic brain injury (TBI). The present investigation examined the impact of mild TBI (mTBI), deployment-related characteristics, and resilience on perceived participation limitations among combat Veterans. This was a cross-sectional study of 143 participants with a history of at least one deployment-related mTBI (TBI group) and 80 without a history of lifetime TBI (Comparison group). Self-report measures of participation, resilience, posttraumatic stress disorder (PTSD) symptoms, and combat exposure were administered. In addition, each participant completed a structured interview to assess lifetime TBI history. The groups did not differ in basic demographics, but significant differences were found for perceived limitations in participation, the presence of PTSD symptoms, and intensity of combat exposure. A stepwise model indicated a significant effect of resilience on reported limitations in participation (adjusted R2 = 0.61). Individuals with higher resiliency reported a higher degree of social participation, and this effect was stronger in the TBI group. Deployment-related characteristics, including intensity of combat exposure, did not have a significant effect (adjusted R2 = 0.28) on social participation. The role of resilience should be recognized within post-deployment transition and rehabilitation programs.
Generalizability of the EAST‐AFNET 4 Trial: Assessing Outcomes of Early Rhythm‐Control Therapy in Patients With Atrial Fibrillation

Background EAST‐AFNET 4 (Early Treatment of Atrial Fibrillation for Stroke Prevention Trial) demonstrated clinical benefit of early rhythm‐control therapy (ERC) in patients with new‐onset atrial fibrillation (AF) and concomitant cardiovascular conditions compared with current guideline‐based practice. This study aimed to evaluate the generalizability of EAST‐AFNET 4 in routine practice. Methods and Results Using a US administrative database, we identified 109 739 patients with newly diagnosed AF during the enrollment period of EAST‐AFNET 4. Patients were classified as either receiving ERC, using AF ablation or antiarrhythmic drug therapy, within the first year after AF diagnosis (n=27 106) or not receiving ERC (control group, n=82 633). After propensity score overlap weighting, Cox proportional hazards regression was used to compare groups for the primary composite outcome of all‐cause mortality, stroke, or hospitalization with the diagnoses heart failure or myocardial infarction. Most patients (79 948 of 109 739; 72.9%) met the inclusion criteria for EAST‐AFNET 4. ERC was associated with a reduced risk for the primary composite outcome (hazard ratio [HR], 0.85; 95% CI, 0.75–0.97 [P=0.02]) with largely consistent results between eligible (HR, 0.89; 95% CI, 0.76–1.04 [P=0.14]) or ineligible (HR, 0.77; 95% CI, 0.60–0.98 [P=0.04]) patients for EAST‐AFNET 4 trial inclusion. ERC was associated with lower risk of stroke in the overall cohort and in trial‐eligible patients. Conclusions This analysis replicates the clinical benefit of ERC seen in EAST‐AFNET 4. The results support adoption of ERC as part of the management of recently diagnosed AF in the United States.
Comparison of Centralized and Peer-to-Peer Decentralized Market Designs for Community Markets

The rapid development of distributed energy resources has posed great challenges to the real-time balance between electricity supply and demand. A suitable market design not only solves the problem of balance but also maximizes social welfare. This article compares two typical community market designs: a centralized manager-based energy market and peer-to-peer (P2P) energy trading that is based on the continuous double auction. First, both market designs and network security verification are presented. Then, in case studies, we quantitatively compare these two market designs in terms of social welfare, the total payment, and the energy trading volume. It is shown that the manager-based energy market facilitates trading energy within the community and with external communities if necessary, but this market design requires collecting information on every market participant to formulate and solve a centralized optimization problem. In contrast, for an energy self-sustaining community, P2P energy trading might be a superb design because it is decentralized, flexible, and privacy-preserving. Meanwhile, with ex post security verification, P2P energy trading can also guarantee the secure operation of the network.
Cu-ion-migration phenomena and its influence on TDDB lifetime in Cu metallization

Time-dependent dielectric breakdown (TDDB) of sub-half-micron Cu interconnects was investigated with regard to the waiting time between Cu-CMP and barrier dielectric deposition. Breakdown voltage and TDDB lifetime between adjacent Cu wires deteriorated abruptly as the waiting time in air passed 4 days. This is due to Cu-ion migration phenomena on the CMP-surface. The degradation can be improved by keeping the samples in a N/sub 2/-box or adopting post-cleaning. This TDDB degradation was observed on any Cu barrier dielectrics in this experiment. In addition, another phenomenon related to Cu TDDB lifetime was discovered, namely a 'fine line effect'. As Cu wire width becomes finer, the TDDB lifetime also decreases further because of the interaction of the electric field at the CMP-surface. It was predicted that the TDDB lifetime for next-generation technology was possibly insufficient for 10-year reliability by testing several low-k dielectrics and Cu barrier dielectrics.
ESTIMATION ELASTIC JUNCTION INFLUENCE ON PARTS AND JOINTS USING MECHANICAL IMPEDANCE METHOD

This paper investigates the application of the mechanical impedance method in determining the amplitude-frequency characteristics of parts and assemblies of internal combustion engines. The developed procedures can be applied to reduce vibrations and vibro-acoustic intensity. Analytical and experimental studies are presented to assess the significance of oil contact surfaces on the complex mechanical resistance. The influence of elastic properties of contact link elements in the mechanical system on transient transfer functions are determined by the mechanical impedance method for "piston-rod" and "rod-crankshaft" assemblies. In the range of resonance frequencies, the transient impedance module could increase by 6-8 dB from the effect of oil layers at the inter-element junctions.
An appraisal of graph embeddings for comparing trophic network architectures

Comparing the architecture of interaction networks in space or time is essential for understanding the assembly, trajectory, functioning and persistence of species communities. Graph embedding methods, which position networks into a vector space where nearby networks have similar architectures, could be ideal tools for this purposes. Here, we evaluated the ability of seven graph embedding methods to disentangle architectural similarities of interactions networks for supervised and unsupervised posterior analytic tasks. The evaluation was carried out over a large number of simulated trophic networks representing variations around six ecological properties and size. We did not find an overall best method and instead showed that the performance of the methods depended on the targeted ecological properties and thus on the research questions. We also highlighted the importance of normalising the embedding for network sizes for meaningful posterior unsupervised analyses. We concluded by orientating potential users to the most suited methods given the question, the targeted network ecological property, and outlined links between those ecological properties and three ecological processes: robustness to extinction, community persistence and ecosystem functioning. We hope this study will stimulate the appropriation of graph embedding methods by ecologists.
Seismic Design Method for Reliability-Based Rehabilitation of Buildings

A reliability-based design method for the rehabilitation of buildings with energy-dissipating devices is proposed. The design method is formulated within the demand and capacity factor design (DCFD) format. The proposed approach is based on verifying that the confidence levels (associated with the serviceability and the ultimate limit states) corresponding to the rehabilitated structure are equal to or larger than the confidence levels associated with a similar conventional structure that is designed in accordance with a reference seismic design code. The method is illustrated with a five-story building rehabilitated with steel TADAS energy-dissipating plates.
On the use of neural network techniques in the analysis of free roll decay curves

In this work, neural network techniques are used to analyze free roll decay curves. The nonlinearities in the roll equation are lumped in one nonlinear function in the roll angle velocity. The technique is then used to identify this general function. This has the advantage of not having to specify the shape of the nonlinearity a priori. The technique has been applied to roll decay curves obtained using numerical simulation and experiments. The agreement between curves predicted using neural network techniques and the actual curves is excellent.
Turbulence Levels are High at the Combustor-Turbine Interface

Turbulence measurements are made in a novel gas turbine rig facility recently used to study combustor-turbine interactions in jet engines [1]. The rig is capable of numerous area traverses surrounding engine turbine nozzle guide vanes (NGVs). The rig is unique in that complete engine hardware of the annular combustion subsystem is used to simulate the upstream flow entering the turbine. The rig operates at cold, near-atmospheric conditions. The turbulence measurements include both the turbulence intensities and lengthscales and span an area over a single combustor sector. Axial measurement planes include locations both upstream and downstream of the real engine hardware NGVs. The upstream plane corresponds to a conventional combustor-turbine interface plane. In [1], pressure, velocity, and passive scalar mixing measurements were presented along with RANS CFD predictions. Here, in addition to the newly measured turbulence quantities, large-eddy simulations (LES) are performed for the complete, coupled combustor-turbine system.Good agreement between rig data and CFD is seen at the combustor-turbine interface, with LES yielding improved predictions over RANS. For the flow through the NGV passages, vortex visualizations of the simulated flowfields show significant differences to the classic, commonly accepted picture of Langston [2] and others [3]. The difference is attributed to the high turbulence levels created by the combustor. The impact of the limitations of the combustor-turbine rig on these findings is discussed.Copyright © 2012 by Rolls-Royce Corporation
A Design of Global Workspace Model with Attention: Simulations of Attentional Blink and Lag-1 Sparing

There are many developed theories and implemented artificial systems in the area of machine consciousness, while none has achieved that. For a possible approach, we are interested in implementing a system by integrating different theories. Along this way, this paper proposes a model based on the global workspace theory and attention mechanism, and providing a fundamental framework for our future work. To examine this model, two experiments are conducted. The first one demonstrates the agent’s ability to shift attention over multiple stimuli, which accounts for the dynamics of conscious content. Another experiment of simulations of attentional blink and lag-1 sparing, which are two well-studied effects in psychology and neuroscience of attention and consciousness, aims to justify the agent’s compatibility with human brains. In summary, the main contributions of this paper are (1) Adaptation of the global workspace framework by separated workspace nodes, reducing unnecessary computation but retaining the potential of global availability; (2) Embedding attention mechanism into the global workspace framework as the competition mechanism for the consciousness access; (3) Proposing a synchronization mechanism in the global workspace for supporting lag-1 sparing effect, retaining the attentional blink effect.
A framework and methodology for reporting geographically and temporally resolved solar data: A case study of Texas

This paper presents a framework and methodology for reporting measured solar radiation data. Geographically and temporally resolved solar data have been calculated for all 254 counties in Texas using geospatial interpolation of data from 24 existing terrestrial measurement locations. Hourly global, direct, and diffuse horizontal radiation data have been obtained from 15 measurement sites at the Texas Solar Radiation Database, a project at The University of Texas at Austin, and from 9 sites at the National Solar Radiation Database. Average radiation fluxes and peak insolation have been calculated using daylight hours in addition to the total energy in kWh∕m2day. The methodology presented in this paper provides solar insolation data in a convenient format for engineers, scientists, policy-makers, homeowners, and consumers to assess the potential of solar energy at the county resolution. This methodology enables informed decisions about the economic viability of solar installations at particular locations an.
Analysis of parasitic effects in triple-well CMOS SPDT switch

A comparison between a conventional body floating single pole double throw (SPDT) CMOS switch design and a proposed switched gate floating CMOS SPDT switch design based on an analysis of parasitic effects is presented. In standard CMOS technology, the switched gate floating switch is analytically proved to have higher isolation owing to the alleviation of parasitic diode and substrate coupling effects in the operation state. The proposed switch maintains a similar insertion loss as conventional swithches while achieving an average of 6 dB isolation improvement over the operating frequency, which agrees well with the presented analysis.
Developing School Leaders: Findings From a Randomized Control Trial Study of the Executive Development Program and Paired Coaching

Principals are the second-largest school-based contributor to K–12 students’ academic progress. However, there is little research evaluating whether efforts to develop principals’ skills improve school effectiveness. We conducted randomized controlled trial studies of the impacts of a professional development program called the Executive Development Program (EDP) and of the incremental effects of coaching to help principals implement the EDP curriculum. We find that the EDP alone influenced principals’ practices, but not student achievement, within 3 years. Coaching had a small positive effect on students’ English Language Arts achievement, but no effect on math achievement or on principals’ practices. Coaching had the largest effects in disadvantaged schools. We hypothesize that coaching enhanced the quality of implementation of recommended practices.
The economic lot and delivery scheduling problem: the common cycle case

We analyze the interface between a supplier and an assembly facility, where direct shipments are made from one to the other. The final manufacturing step at the supplier involves multiple components produced on a single machine or production line. The assembly facility uses these components at a constant rate. The supplier incurs a sequence-independent setup cost and/or setup time each time the production line is changed over from one component to another. On the other hand, setup costs and times for the assembly facility are negligible. We consider two types of delivery cost: a fixed charge for each delivery, and a fixed-charge-per-truck cost. We develop a heuristic procedure to find a ‘just-in-time’ schedule in which one production run of each product and a subsequent delivery of these products to the assembly facility occur in each cycle. The objective is to find the cycle duration that minimizes the average cost per unit time of transportation, inventory at both the supplier and the assembly facility,.
Development and Validation of Perceived Oral Health Benefits on Yoga Scale (POBYS)

Objective: Sustained practice of Yoga leads to self-awareness, physical strength and high sense of energy. Yoga stimulates antioxidant levels in the body and reduces likelihood of dental disorders. No research has been undertaken connecting perception on yoga and oral health behaviors. The present study is an attempt to develop a psychometric scale entitled Perceived Benefits on Yoga Scale (PBYS) to measure individuals’ perception on Yoga in relation to oral health behaviors. Material and methods: The psychometric tool was developed based on the concepts of Health Benefit Model (HBM). Among the four components of the model, the present study considered “perceived benefits” component. A total of 206 individuals participated in the study. To analyze the scale theoretically, face and content validity were assessed. Reliability of the scale was tested using Cronbach’s alpha and Spearman-Brown coefficient. Using exploratory and confirmatory factor analysis, construct validity was tested. Cronbach alpha and Spearman- Brown coefficient were applied to test the reliability of scale. Results: There were six items in the final scale, with a Spearman- Brown coefficient of 0.92 and Cronbach’s alpha of 0.91. Statistically significant (p < 0.001) positive correlation was found between POBYS scores and Yoga Self-Efficacy Scale (YSES). Validity of scale is within accepted range as indicated by Goodness of Fit indices. Conclusion: POBYS is a reliable and valid measure of perception on yoga outcomes with specific reference to oral health behavior. Keywords Yoga; Health belief model; Oral health behavior; Scale development; Confirmatory factor analysis.
Efficient Variance Reduction for American Call Options Using Symmetry Arguments

Recently it was shown that the estimated American call prices obtained with regression and simulation based methods can be significantly improved on by using put-call symmetry. This paper extends these results and demonstrates that it is also possible to significantly reduce the variance of the estimated call price by applying variance reduction techniques to corresponding symmetric put options. First, by comparing performance for pairs of call and (symmetric) put options for which the solution coincides, our results show that efficiency gains from variance reduction methods are different for calls and symmetric puts. Second, control variates should always be used and is the most efficient method. Furthermore, since control variates is more effective for puts than calls, and since symmetric pricing already offers some variance reduction, we demonstrate that drastic reductions in the standard deviation of the estimated call price is obtained by combining all three variance reduction techniques in a symmetric pricing approach. This reduces the standard deviation by a factor of over 20 for long maturity call options on highly volatile assets. Finally, we show that our findings are not particular to using in-sample pricing but also hold when using an out-of-sample pricing approach.
Convergence Study for Rock Unconfined Compression Test Using Discrete Element Method

Mesh convergence is a vital issue that needs to be addressed in a numerical model. This study investigated the effects of mesh element number on the Discrete Element Method (DEM) to granite rock response under compression loading. This study used the 3D finite-element code LS-DYNA to model the Unconfined Compression Test (UCT) numerical simulation. Models with five different mesh types were conducted for convergence mesh, namely normal mesh, fine mesh, super fine mesh, coarse mesh, and super coarse mesh. The mesh convergence of rock media has been conducted using DEM and steel plates simulated using the Finite Element Method (FEM). The DEM-FEM numerical analysis is compared with the results obtained from the experimental test. The best mesh was obtained as the simulation could reproduce the stress-strain curve trends, the failure behaviour and compression strength observed in the experimental test. The normal mesh was selected as the best mesh type in this study based on the comparisons that have been made. This study shows that the DEM-FEM numerical simulation can represent granite rock and can be used for further study based on mesh convergence.