Miracle-dz/UniFAR-FTUs huggingface dataset:
Gravimetric methods for the preparation of standard gas mixtures

The most widely used method for the preparation of primary standard gas mixtures involves weighing the individual components into a cylinder. We present a new mathematical description of the method and its uncertainties. We use this to demonstrate how strategies for serial dilution can be identified that minimize the uncertainty in the final mixture and show how they can be implemented practically. We review published reports of high accuracy gravimetry and give examples of relative uncertainties in the composition of standards approaching 1 part-per-million in the best cases and in the range of 100 to 1000 parts-per-million more typically.
German National Socialism and the Quest for Nuclear Power: 1939–1949

Introduction Part I. Lightning War: Nuclear fission The German nuclear power project Moderators, isotope separation, and uranium machines Nuclear power and lightning war Part II. The War Slows Down: The end of the lightning war Nuclear power conferences National Socialism and German physics Progress and infighting Part III. The War Comes Home: Wonder weapons Uranium machines in Berlin-gottow Greater Germany and cultural imperialism Death from above and betrayal from within Part IV. The War is Lost: Evacuation and self-preservation The heavy water dries up Harteck's circle, centrifuges, and special experiments Uranium machines and rock cellars Part V. The German Achievement in the American Shadow: The Alsos MIssion Farm Hall The Smyth Report Part VI. The Legacy of German National Socialism: The occupation of Germany Nazification and denazification The Goudsmit/Heisenberg controversy Part VII. The Myth of the German Atomic Bomb: Conclusion Notes Bibliography Index.
A new method for the determination of membrane permeability by spatially resolved concentration measurements

This paper suggests a novel method for determining the permeability of a membrane by spatially resolved measurements of the concentration profiles above and below the membrane. A compact diode laser absorption spectrometer is presented with a collimated measuring beam, allowing precise concentration measurements with a spatial resolution of 200 µm perpendicular to the laser beam. Measurements of the permeability of polyurethane coated polypropylene foils are presented, demonstrating the ability of fast and calibration-free measurements.
Heavy Precipitation Associated with Southern Appalachian Cold-Air Damming and Carolina Coastal Frontogenesis in Advance of Weak Landfalling Tropical Storm Marco (1990)

Abstract An analysis is presented of Tropical Storm Marco (1990), a storm that dropped copious amounts of rain over the southeast United States. Marco was noteworthy because of its role in the formation and evolution of two distinct episodes of cold-air damming and coastal frontogenesis over Georgia and the Carolinas. These mesoscale features led to greater than 300 mm of precipitation in 2 days over the near-coastal southeast United States; much of the rain occurred while Marco was over 400 km away. This case is further complicated by two other nearby tropical cyclones, which affected Marco’s track and the overall rainfall distribution. Synoptic and mesoscale analyses of the development of the coastal front and cold-air damming episodes show that the location of Marco helped to orient low-level winds toward the Appalachians. As rain developed inland, a pocket of relatively cool air, the “cool pool,” formed near the mountain slopes and was partially blocked by the higher terrain. Low-level analyses show t.
Association of Race With Post-operative Complications After Spinal Fusion in Children With Cerebral Palsy

Introduction: Neuromuscular scoliosis in children with cerebral palsy (CP) can lead to debilitating difficulties with pain, ambulation, sitting, and respiratory or cardiac compromise. Spinal fusion can halt deformity progression, though the decision to undergo surgery involves an individualized risk-benefit assessment. The purpose of this study was to evaluate whether race is a risk factor for patients with CP to experience post-operative complications after spinal fusion. Methods: This is a retrospective cohort analysis of a national database. Analyses methods include univariate analyses, multivariate regression models, and other ad-hoc tests. Results: There were 3,081 pediatric patients with CP who underwent spinal fusion. Black patients had an increased risk of experiencing any post-operative complication compared to Caucasians (OR 1.322, 95% CI 1.099-1.590). Both Caucasian(p=0.005) and Black (p<0.001) races were risk factors for experiencing medical complications; Black patients had an increased risk compared to Caucasians (OR 1.373, 95% CI 1.130-1.667). Other races had a greater length of ICU stay than Caucasians (median {Mdn}=3.00 days vs Mdn=2.00, p=0.029), and longer total hospital stays than Caucasian and Black patients (Mdn=9.00 days vs Mdn=6.00 days vs Mdn=6.00 days, p<0.001). Conclusion: Race is an independent risk factor for pediatric patients with CP to experience medical complications following spinal fusion surgery, with Black patients having an increased risk compared to Caucasians. Further, other races were found to have significantly longer ICU and total hospital length of stay. This study is the first to present race as a risk factor for children with CP to experience increased post-operative complications following spinal fusion and will be valuable in understanding their individualized peri-operative courses and risks.
Fundamental and derived modes of climate variability: concept and application to interannual time-scales

The notion of mode interaction is proposed as a deterministic concept for understanding climatic modes at various timescales. This concept is based on the distinction between fundamental modes relying on their own physical mechanisms and derived modes that emerge from the interaction of two other modes. The notion is introduced and applied to interannual climate variability. Observational evidence is presented for the tropospheric biennial variability to be the result of the interaction between the annual cycle and a quasi-decadal mode originating in the Atlantic basin. Within the same framework, Pacific interannual variability at time-scales of about 4 and 6 yr is interpreted as the result of interactions between the biennial and quasi-decadal modes of climate variability. We show that the negative feedback of the interannual modes is linked to the annual cycle and the quasi-decadal mode, both originating outside the Pacific basin, whereas the strong amplitudes of interannual modes result from resonance and local positive feedback. It is argued that such a distinction between fundamental and derived modes of variability is important for understanding the underlying physics of climatic modes, with strong implications for climate predictability.
E-ELT primary mirror control system

During the past year the control of the 42m segmented primary mirror of the E-ELT has been studied. This paper presents the progress in the areas of M1 figure control and control hardware implementation. The critical issue of coupling through the supporting structure has been considered in the controller design. Different control strategies have been investigated and from a tradeoff analysis modal control is proposed as a solution addressing the topics of wind rejection as well as sensor noise in the presence of cross-coupling through the supporting structure. Various implementations of the M1 Control System have been studied and a centralized architecture has been selected as baseline. This approach offers maximum flexibility for further iterations. The controller design and main parts of the control system are described.
Detection of Schizophrenia from EEG Signals using Dual Tree Complex Wavelet Transform and Machine Learning Algorithms

This research was conducted with the aim to detect schizophrenia automatically from EEG signals using machine learning algorithms. The 16 electrode EEG data were collected from the online repository where 43 schizophrenic and 39 healthy persons’ dataset is available. By applying Low Pass Filter and Total Variation Denoising method, raw EEG signals were denoised and were decomposed into beta, alpha, theta and delta waves by using Dual Tree Complex Wavelet Transform. To apply machine learning algorithms, five features: mean, median, standard deviation, energy and kurtosis were considered for all the four wave bands. With Linear Support Vector Machine and Random Forest classifier machine learning algorithms, 12 out of 16 channels were classified with test accuracy above 95% and F1 score above 90%. Among them, 7 channels were predicted with 100% test accuracy. This research thus has the potential to detect schizophrenia unsupervised and within a noticeably short period of time giving the opportunity to real time monitoring of patients. Hence, people living in remote areas or deprived of adequate healthcare professionals can be benefitted through the outcome of this research. Bangladesh Journal of Medical Physics Vol.15 No.1 2022 P 8-27
EULERIAN-LAGRANGIAN COMPUTATIONS ON PHASE DISTRIBUTION OF TWO-PHASE BUBBLY FLOWS

SUMMARY A comprehensively theoretical model is developed and numerically solved to investigate the phase distribution phenomena in a two-dimensional, axisymmetric, developing, two-phase bubbly flow. The Eulerian approach treats the fluid phase as a continuum and solved Eulerian conservation equations for the liquid phase. The Lagrangian bubbles are tracked by solving the equation of motion for the gas phase. The interphase momentum changes are included in the equations. The numerical model successfully predicts detailed flow velocity profiles for both liquid and gas phases. The development of the wall-peaking phenomenon of the void fraction and velocity profiles is also characterized for the developing flow. For 42 experiments in which the mean void fraction is less than 20 per cent, numerical calculations demonstrate that the predictions agree well with Liu’s experimental data. 1997 by John Wiley & Sons, Ltd.
THERMO FIELD DYNAMICS

A quantum field theory at finite temperature is presented. The temperature dependent vacuum is defined such that the vacuum expectation value agrees with the statistical average. The vacuum states with different temperature are connected by a Bogoliubov transformation. Our formalism allows the use of the Feynman diagrams for the causal Green’s function and the Bethe-Salpeter technique for bound states at finite temperature, The entropy operator is introduced.
The Research of High-Dimensional Big Data Dimension Reduction Strategy

With the increase of data dimension, many low dimensional mining algorithms cannot get satisfactory results. With the increase of data dimension, it can produce a large amount of redundant information; this information will greatly reduce the efficiency of mining, increasing the complexity of the mining algorithm. Feature selection is an efficient way to solve the problem; it can remove a lot of irrelevant and redundant features. In this paper, on the basis of Lars algorithm applying differential evolution thought to the extraction of feature subset, puts forward a new method of feature selection, DE - Lars algorithm. Experiments prove that DE - Lars algorithm enhances the precision of reducing dimension of space, effectively solve the problem of "Curse of Dimensionality ".
Numerical and Experimental Analysis of the Growth of Gravitational Interfacial Instability Generated by Two Viscous Fluids of Different Densities

In the geophysical context, there are a wide variety of mechanisms which may lead to the formation of unstable density stratification, leading in turn to the development of the Rayleigh-Taylor instability and, more generally, interfacial gravity-driven instabilities, which involves moving boundaries and interfaces. The purpose of this work is to study the level set method and to apply the process to study the Rayleigh-Taylor instability experimentally and numerically. With the help of a simple, inexpensive experimental arrangement, the R-T instability has been visualized with moderate accuracy for real fluids. The same physical phenomenon has been investigated numerically to track the interface of two fluids of different densities to observe the gravitational instability with the application of level set method coupled with volume of fraction replacing the Heaviside function. Good agreement between theory and experimental results was found and growth of instability for both of the methods has been plotted.
Video-based measurements for wireless capsule endoscope tracking

The wireless capsule endoscope is a swallowable medical device equipped with a miniature camera enabling the visual examination of the gastrointestinal (GI) tract. It wirelessly transmits thousands of images to an external video recording system, while its location and orientation are being tracked approximately by external sensor arrays. In this paper we investigate a video-based approach to tracking the capsule endoscope without requiring any external equipment. The proposed method involves extraction of speeded up robust features from video frames, registration of consecutive frames based on the random sample consensus algorithm, and estimation of the displacement and rotation of interest points within these frames. The results obtained by the application of this method on wireless capsule endoscopy videos indicate its effectiveness and improved performance over the state of the art. The findings of this research pave the way for a cost-effective localization and travel distance measurement of capsule endoscopes in the GI tract, which could contribute in the planning of more accurate surgical interventions.
Impacts of COVID-19 on U.S. Apparel Industry Based on the Fama-French Five Factor Model

The COVID-19 pandemic has caused a grievous global economic loss and many industries were destroyed by this crisis. Nevertheless, many apparel companies had a remarkable financial performance last year. This research applied the Fama-French Five Factor Model to analyze the influence on the apparel industries under the epidemic. Based on the daily data from Kenneth R. Frencha’s database, this paper chose the relevant 18 months data, selecting the outbreak point in February, 2020, as the dividing line. June, 2019 to February, 2020 is the period that before the pandemic, while March, 2020 to November, 2020 is the post-pandemic period. According to the results by multiple regression analysis, it found out that coronavirus pandemic had a radical effect on the apparel industry. Under the influence of COVID-19, investors preferred to put their money in relative aggressive companies to seek new investment opportunities. Therefore, investors need to pay attention to the financial situation and its product, which could be risky for their future development.
Computationally Efficient Algorithms for Parameter Estimation and Uncertainty Propagation in Numerical Models of Groundwater Flow

Finite difference and finite element methods are frequently used to study aquifer flow; however, additional analysis is required when model parameters, and hence predicted heads are uncertain. Computational algorithms are presented for steady and transient models in which aquifer storage coefficients, transmissivities, distributed inputs, and boundary values may all be simultaneously uncertain. Innovative aspects of these algorithms include a new form of generalized boundary condition; a concise discrete derivation of the adjoint problem for transient models with variable time steps; an efficient technique for calculating the approximate second derivative during line searches in weighted least squares estimation; and a new efficient first-order second-moment algorithm for calculating the covariance of predicted heads due to a large number of uncertain parameter values. The techniques are presented in matrix form, and their efficiency depends on the structure of sparse matrices which occur repeatedly throughout the calculations. Details of matrix structures are provided for a two-dimensional linear triangular finite element model.
Coherent optical manipulation of a single spin state in a charged quantum dot: theory and modelling

The optically-induced coherent spin dynamics in a charged quantum dot (QD) is studied theoretically using a new dynamical model for rigorous description of circularly polarized ultrashort optical pulse resonant interactions with the electron-trion system. Generalized pseudospin master equation is derived for description of the time evolution of spin coherences and spin populations in terms of the real state pseudospin (coherence) vector including dissipation in the system through spin relaxation processes. The equation is solved in the time domain self-consistently with the vector Maxwell equations for the optical wave propagation coupled to it via macroscopic medium polarization. Using the model the long-lived electron spin coherence left behind a single resonant ultrashort optical excitation of the electron-trion transition in a charged QD is simulated in the lowand high-intensity Rabi oscillations regime. Signatures of the polarized photoluminescence (PL) resulting from the numerical simulations, such as the appearance of a second echo pulse after the excitation and a characteristic PL trace shape, specific for initial spin-up orientation, are discussed for realization of high-fidelity schemes for coherent readout of a single spin polarization state.
Compact Radio Sources with the Steepest Spectra

We used the 1.4 GHz NRAO VLA Sky Survey (NVSS) and 365 MHz Texas survey catalogs to select relatively compact (θ ≤ 25′′) radio sources having exceptionally steep spectral indices α ≥ 1.5 (where the flux density Sν at frequency ν scales as Sν ∝ ν-α). Our sample of 74 sources (of ~30,000 total sources common to both surveys) with S(365 MHz) ≥ 200 mJy in the 10 sr between δ = -35°30′ and δ = 71°30′ should be complete for spectra as steep as α = 3.2, but we found only four sources with α > 2.5. Most known sources with such steep spectra are pulsars (coherent radio sources), relic radio galaxies, and high-redshift radio galaxies (synchrotron sources with spectra steepened by radiation losses). In fact, six of our sources have been identified with known pulsars and one with a high-redshift (z = 3.79) radio galaxy. In order to find possible new populations of steep-spectrum sources and classify the rest, we made VLA images of our sources with 1. ″5 and 0. ″5 resolution at 1.4 and 5 GHz, respectively. There are 25 doubles, 24 multicomponent sources, 16 unresolved (θ ≲ 0.″2) sources, and six known pulsars. Three sources have undetermined morphologies as they were not reobserved with the VLA. The smallest sources have exceptionally steep spectra for their angular sizes. New pulsars, if any, are likely to be of special interest since they are strong but were missed by pulse-detection surveys. Preliminary radio, infrared, and optical observations suggest that most are high-redshift extragalactic sources.
Pre-testing in a mis-specified regression model

We consider the pre-test estimation of the parameters of a linear regression model after a preliminary-test for exact linear restrictions when the model is mis-specified through the omission of relevant regressors and the usual assumption of normal regression disturbances is widened to a subclass of the family of spherically symmetric errors. We derive and analyse the exact risk (under quadratic loss) of a pre-test estimator of the prediction vector and of the scale parameter.
Finite spectrum assignment and observer for multivariable systems with commensurate delays

This paper is concerned with control of multivariable systems with commensurate delays. The purpose of this paper is to enlarge the class of finite spectrum assignable systems to spectrally controllable multivariable systems with commensurate delays. By overcoming an infinite number of eigenvalues which are contained in the system and make control very complex, it is proved that if the system is spectrally controllable, there is a delayed feedback matrix such that the closed-loop system is spectrally controllable through a single input. Combining this result with previous ones about single-input systems, it is verified that spectral controllability is equivalent to finite spectrum assignability for multivariable systems with commensurate delays. An observer for the system with delayed outputs is presented. By using these results, the multivariable system can be regulated as desired without preliminary knowledge of open-loop eigenvalues and a stability test of transcendental functions whenever the system is spectrally controllable and spectrally observable.
Exploring English Language Teaching in Ecuadorian Secondary Schools: Teachers’ Beliefs About the National Curriculum Reform

The present study explored the Ecuadorian secondary school teachers' beliefs about teaching EFL in the context of national curriculum reform. The data comprised in-depth interviews with 16 teachers from 14 public secondary schools in Ecuador. The interviews were semi-structured, and they were guided by a set of questions probing into the teachers‟ beliefs about instructional design, assessment, teaching materials
Teacher Professional Practical Training Module for Teachers Assistant in Guiding Practice Students in Managing Learning

The ability to accompany teachers in guiding student practitioners that is less than optimal causes a decrease in the quality of learning management. Lack of understanding and awareness of managing learning in terms of learning practices must receive serious attention, provide instruments in clear modules or guidelines, and post-implementation evaluations. This study aims to develop a teacher's professional practice training module for teacher assistants to guide students' practice in managing to learn. The type of model and design used is research and development by combining the Rowntree, Borg, and Gall models. The study subjects were assistant teachers at the Early Childhood Education Unit and Elementary School, totaling 40 people. Methods of collecting data through observation, interviews, and documentation studies. The data analysis techniques are descriptive qualitative analysis and statistical inferential. The results of the study were the results of the assessment by material experts (93.64%), design experts (88.57%), and media experts (86.75%), who stated that the teacher training professional practice module developed was feasible to use. The results of individual and group trials of 30 respondents also experienced an increase, with a free test score of 76.33% and a post-test score of 84.37%. These results indicate an increase in the ability to guide teachers accompanying students with learning outcomes of 8.04, so the teaching professional practice training module for accompanying teachers is feasible and effective.
Bendable integrated circuits on plastic substrates by use of printed ribbons of single-crystalline silicon

This letter presents studies of several simple integrated circuits—n-channel metal-oxide semiconductor inverters, five-stage ring oscillators, and differential amplifiers—formed on thin, bendable plastic substrates with printed ribbons of ultrathin single-crystalline silicon as the semiconductor. The inverters exhibit gains as high as 2.5, the ring oscillators operate with oscillation frequencies between 8 and 9MHz at low supply voltages (∼4V), and the differential amplifiers show good performance and voltage gains of 1.3 for 500mV input signals. The responses of these systems to bending-induced strains show that relatively moderate changes of individual transistors can be significant for the operation of circuits that incorporate many transistors.