Miracle-dz/UniFAR-FTUs huggingface dataset:
Solar wind models with Alfven waves

The purpose of this paper is to study the effects of wave pressure and wave heating on one-fluid models of the solar wind. Solutions are given to the MHD equations for the solar wind which include fluxes of Alfven waves ranging from 0 to approx.10/sup 5/ ergs cm/sup -2/ s/sup -1/ at the base of the corona. Damping of the waves is simulated by limiting the wave magnetic field amplitude to that of the background magnetic field. Two states of the solar wind, which we refer to as fast (high-speed streams), with speeds approx.700 km s/sup -1/, and slow, with speeds approx.300 km s/sup -1/, are considered. Particular attention is paid to the fast solutions because of recent evidence suggesting that the properties of high-speed streams are more characteristic of the global solar wind than those of low-speed flows.Two problems which are common to all ''conduction models'' of the solar wind, i.e., models which have no energy supply other than thermal conduction from the inner boundary, are that the density profile is too flat and the flow velocity at 1 AU is too low. For high-speed streams these discrepancies are especially pronounced, and the requirement for extended heating and accelerationmore » is more stringent for high-speed streams than for low-speed flows. The most significant success of the models presented here is the ability to reproduce observed densities both at the Sun and at 1 AU, and to produce flows with speeds approx.750 km s/sup -1/ at 1 AU, simply by including an Alfven wave flux at the Sun of approx.10/sup 5/ ergs cm/sup -2/ s/sup -1/. The inclusion of waves steepens the density profile near the Sun, making it possible to construct models with electron densities near the Sun of several times 10/sup 8/ cm/sup -3/ which also match density and velocity observations at 1 AU. « less
On the linear instability of a finite Stokes layer: Instantaneous versus Floquet modes

The linear instability of a finite Stokes layer is investigated numerically. The aim is to clarify the relationship between the instantaneous instability and the recently discovered Floquet global instability [P. J. Blennerhassett and A. P. Bassom, J. Fluid Mech. 464, 394 (2002); P. J. Blennerhassett and A. P. Bassom, J. Fluid Mech. 556, 1 (2006)], and their role in causing transition to turbulence. For the first time, a numerical approach based on initial-value calculations is able to confirm the global instability, which occurs as the Reynolds number R (based on the Stokes-layer thickness) exceeds the critical value Rc=708. In both supercritical (R>Rc) and subcritical (R<Rc) regimes, strong instantaneous growth occurs during the deceleration phase. By projecting the disturbance at an arbitrary instant to instantaneous eigenfunctions, it is shown that the energy of the disturbance is primarily carried by the most unstable instantaneous mode. During the main growing phase, both the spatial structure and t.
Magnetic Damping of the Angular Motions of Earth Satellites

1 Kerrebrock, J. L. and Meghreblian, R. V. , "An Analysis of Vortex Tubes for Combined Gas-Phase Fission Heating and Separation of the Fissionable Material," ORNL CF-57-11-3, revision 1, April 11, 1958. 2 Kerrebrock, J. L. and LaFyatis, P. G. , "Analytical Study of Some Aspects of Vortex Tubes for Gas-Phase Fission Heating," ORNL CF-587-4, July 1958. 3 Kerrebrock, J. L. and Keyes, J. J., Jr., "A Preliminary Experimental Study of Vortex Tubes for Gas-Phase Fission Heating," ORNL-2660, February 1959. 4 Keyes, J. J., Jr. and Dial, R. E. , "An Experimental Study of Vortex Flow for Application to Gas-Phase Fission Heating, O'RNL-2837, April 1960. 5 Keyes, J. J., Jr., Heat Transfer and Fluid Mechanics Institute, Stanford Univ. Press, 1960, pp. 31-46. 6 Ragsdale, R. G. , "NASA Research on the Hydrodynamics of the Gaseous Vortex Reactor," NASA-TN-D-288, June 1960. 7 Einstein, H. A. and Li, H. , Heat Transfer and Fluid Mechanics Institute, Stanford Univ. Press, 1951, pp. 33-43. 8 Jet Propulsion Laboratory Research Summary no. 36-3, vol. 1, part 2, June 1960. 9 Pengelley, C. D. , "Flow in a Viscous Vortex," J. of Appl. Fhys. , vol. 28, no. 1, January 1957, p. 86. 10 Schoenherr, K. E. , Trans, of the Soc. of Aaval Architects and Marine Engineers. Vol. 40, 1932, pp. 279-313.
Environmentally-Aware and Energy-Efficient Multi-Drone Coordination and Networking for Disaster Response

In a disaster response management (DRM) scenario, communication and coordination are limited, and absence of related infrastructure hinders situational awareness. Unmanned aerial vehicles (UAVs) or drones provide new capabilities for DRM to address these barriers. However, there is a dearth of works that address multiple heterogeneous drones collaboratively working together to form a flying ad-hoc network (FANET) with air-to-air and air-to-ground links that are impacted by: (i) environmental obstacles, (ii) wind, and (iii) limited battery capacities. In this paper, we present a novel environmentally-aware and energy-efficient multi-drone coordination and networking scheme that features a Reinforcement Learning (RL) based location prediction algorithm coupled with a packet forwarding algorithm for drone-to-ground network establishment. We specifically present two novel drone location-based solutions (i.e., heuristic greedy, and learning-based) in our packet forwarding approach to support application requirements. These requirements involve improving connectivity (i.e., optimize packet delivery ratio and end-to-end delay) despite environmental obstacles, and improving efficiency (i.e., by lower energy use and time consumption) despite energy constraints. We evaluate our scheme with state-of-the-art networking algorithms in a trace-based DRM FANET simulation testbed featuring rural and metropolitan areas. Results show that our strategy overcomes obstacles and can achieve 81-to-90% of network connectivity performance observed under no obstacle conditions. In the presence of obstacles, our scheme improves the network connectivity performance by 14-to-38% while also providing 23-to-54% of energy savings in rural areas; the same in metropolitan areas achieved an average of 25% gain when compared with baseline obstacle awareness approaches with 15-to-76% of energy savings.
Ion peening and stress relaxation induced by low-energy atom bombardment of covalent solids

Using molecular-dynamics simulation, we study the buildup and relaxation of stress induced by low-energy ({le}150 eV) atom bombardment of a target material. The effect is brought out most clearly by using an initially compressed specimen. As target material, we employ Si, based on the Tersoff potential. By varying the bond strength in the potential, we can specifically study its effect on damage production and stress changes. We find that in general, stress is relaxed by the atom bombardment; only for low bombarding energies and strong bonds, atom bombardment increases stress. We rationalize this behavior by considering the role of energized atoms and of recoil-implanted target atoms.
Multifrequency observations of Cygnus X-2 X-ray observations with GINGA

Les observations RX, realisees par le satellite Ginga en juin et octobre 1988 dans le cadre d'observations multifrequences (Hjellming R. M. et al, van Paradijs J. et al, Vrtilek S. D. et al, 1990, Astron. Astrophys., 235), de la binaire RX a faible masse et source Z, Cyg X-2, sont presentees. Les courbes de lumiere et les diagrammes 2 couleurs sont analyses. Un ajustement du spectre de puissance est realise.
Optimized precision micromachining using commercially available high-repetition rate microjoule femtosecond fiber lasers

Fiber lasers offer an excellent technology base for production of an industrial-quality tool for precision microfabrication, answering the need to expand the capabilities of laser material processing beyond traditional welding, cutting, and other industrial processes. IMRA's FCPA μJewelTM femtosecond fiber laser has been developed to address the particular need for direct-write lasers for creation of clean and high-quality micron and sub-micron features in materials of commercial interest. This flexible Yb:fiber chirped-pulse amplification architecture, capable of operating at rep-rates between 100 kHz and 5 MHz, balances the need for higher-repetition rate with that of sufficient pulse energy to work at or near ablation threshold, while meeting industrial standards for temperature, shock and vibration. Demonstration of the need for higher-repetition rates for direct write processes will be provided in this paper. Further, results of laser-processing of materials typically used in flat panel displays, photomasks, and waveguide production using the FCPA μJewelTM laser will be presented.
Corporate Political Connections: A Multidisciplinary Review

Corporate political connections (CPCs)—ties that firms forge with political actors—directly affect firms, political actors, and various stakeholders in societies. This topic has been studied extensively in multiple disciplines, including management, economics and finance, political science, and sociology. However, this body of research remains rather fragmented within the confines of each discipline or field, and synergies in theoretical and empirical domains remain underexploited. Differences between CPCs and other forms of corporate political activities are also often unclear. This article develops a focused, comprehensive, and theoretically deep review of the rapidly growing but disparate literature on CPCs in multiple disciplines and fields and distinguishes, compares, and connects multiple, heterogeneous theoretical perspectives that have been adopted in these different literatures. By conducting an extensive literature search of the articles published between 1990 and 2020 in 24 leading peer-reviewed journals in management, economics and finance, political science, and sociology, we build our review framework by organizing the reviewed articles into three groups of topics based on their logical connections: the conceptualization of CPCs, the antecedents of CPCs, and the outcomes of CPCs. Within each group, we distinguish two primary angles—the firm and the political actor—that correspond to the two entities joined by CPCs. On the basis of this framework, we identify major gaps and suggest avenues for future research. Our review works together with a companion review on corporate political activity, published in this same issue, to offer a wholistic perspective on the boundary between corporations and political actors.
High-Precision Tip Tracking of a Flexible Link Manipulator Using Two-Time Scale Adaptive Robust Control

A flexible link manipulator (FLM) has advantages of greater payload-to-manipulator-weight ratio, safer operation, and lower energy consumption compared with the rigid manipulator, which has promising demands in various industrial and aerospace applications. However, the internal dynamics of the system is easy to be unstable due to its nonminimum phase characteristics, and there exists severe parametric uncertainties and uncertain nonlinearities in its dynamics, which has brought many difficulties in the precise tip tracking control and effective vibration suppression. In this article, the entire mathematical model of the FLM is established with assumed mode method and actuator dynamics. Then, the system is decomposed into a slow subsystem and a fast subsystem through introducing an adjustable time-scale factor according to a new output redefined dynamics with uncertainties from truncated vibration modes and unknown disturbances of system. A two-time scale adaptive robust control (TTSARC) scheme, which consists of an adaptive robust control for the slow subsystem and a state feedback control for the fast subsystem, is proposed to effectively handle parametric uncertainties and uncertain nonlinearities as well as improve behavior of internal dynamics. Moreover, the clear connection of achievable performances and control parameters based on the stability analysis of the entire system is addressed. The experimental results indicate that precise tip tracking with small link deflection for the FLM working on different conditions can be achieved with the proposed TTSARC.
ESTIMATION OF A PROJECTION-PURSUIT TYPE REGRESSION MODEL'

Since the pioneering work of Friedman and Stuetzle in 1981, projection-pursuit algorithms have attracted increasing attention. This is mainly due to their potential for overcoming or reducing difficulties arising in nonparametric regression models associated with the so-called curse of dimensionality, that is, the amount of data required to avoid an unacceptably large variance increasing rapidly with dimensionality. Subsequent work has, however, uncovered a dependence on dimensionality for projection-pursuit regression models. Here we propose a projection-pursuit type estimation scheme, with two additional constraints imposed, for which the rate of convergence of the estimator is shown to be independent of the dimensionality. Let (X, Y) be a random vector such that X = (X1, . . , Xd)T ranges over Rd. The conditional mean of Y given X = x is assumed to be the sum of no more than d general smooth functions of 87[x, where p3i E Sd-1, the unit sphere in Rd centered at the origin. A least-squares polynomial spline and the final prediction error criterion are used to fit the model to a random sample of size n from the distribution of (X, Y). Under appropriate conditions, the rate of convergence of the proposed estimator is independent of d.
Antidisturbance Control for Hidden Markovian Jump Systems: Asynchronous Disturbance Observer Approach

This article investigates the antidisturbance control issue for a class of Markovian jump systems with matched/mismatched disturbances by using disturbance observer approach. A key feature here is that the external disturbance is considered to be generated by a Markovian jump exogenous dynamics, in which the disturbance mode may not be synchronized with the system mode. Meanwhile, it is supposed that both system and disturbance modes can just be estimated via a hidden Markov mode detector. To overcome the possible obstacle in handling dual hidden Markov modes, a mapping technique for continuous-time Markov chain is provided first. Then, a novel asynchronous disturbance observer is developed to estimate the external disturbance by utilizing the detected mode. Based upon the estimated disturbance, asynchronous antidisturbance controllers are investigated for matched and mismatched disturbance cases, respectively. By employing a decoupling technique with the idea of completing the square, sufficient conditions are established for guaranteeing the stability in probability of the resultant closed-loop systems. Finally, two numerical examples are provided to verify the effectiveness of the proposed asynchronous antidisturbance control approaches under inaccessible system and disturbance modes.
MODIS aerosol optical thickness retrieval using deep belief network

Aerosols are important pollutants affecting the quality of atmospheric environment. With the development of space remote sensing technology, using satellite remote sensing to retrieve aerosol has become an important method. In order to solve the ill-posed problem of aerosol retrieval and to mine the aerosol information of satellite signals to a greater extent, this paper proposes a method based on deep confidence network to realize the aerosol retrieval of MODIS sensor. AERONET station data and satellite data in the Beijing-Tianjin-Hebei region of China were selected, and the sample dataset was constructed according to the reasonable spatio-temporal matching principle. By setting relevant parameters, the model is trained and tested, and the optimal network model is found. The aerosol measured data from independent AERONET sites were selected for accuracy evaluation, and the accuracy reached 97.78%. Compared with the traditional aerosol inversion algorithm, the proposed method achieves high precision and high efficiency of aerosol inversion, and improves the stability and spatio-temporal adaptability of aerosol inversion.
Evaluation of potential emission spectra for the reliable classification of fluorescently coded materials

The conservation and efficient use of natural and especially strategic resources like oil and water have become global issues, which increasingly initiate environmental and political activities for comprehensive recycling programs. To effectively reutilize oil-based materials necessary in many industrial fields (e.g. chemical and pharmaceutical industry, automotive, packaging), appropriate methods for a fast and highly reliable automated material identification are required. One non-contacting, color- and shape-independent new technique that eliminates the shortcomings of existing methods is to label materials like plastics with certain combinations of fluorescent markers ("optical codes", "optical fingerprints") incorporated during manufacture. Since time-resolved measurements are complex (and expensive), fluorescent markers must be designed that possess unique spectral signatures. The number of identifiable materials increases with the number of fluorescent markers that can be reliably distinguished within the limited wavelength band available. In this article we shall investigate the reliable detection and classification of fluorescent markers with specific fluorescence emission spectra. These simulated spectra are modeled based on realistic fluorescence spectra acquired from material samples using a modern VNIR spectral imaging system. In order to maximize the number of materials that can be reliably identified, we evaluate the performance of 8 classification algorithms based on different spectral similarity measures. The results help guide the design of appropriate fluorescent markers, optical sensors and the overall measurement system.
Resistance to Antibody-Drug Conjugates Targeting HER2 in Breast Cancer: Molecular Landscape and Future Challenges

Simple Summary Human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (mBC) represents a subgroup of breast cancer characterized by an aggressive behaviour and a particular sensitiveness to HER2-targeted agents. Because of the frequent occurrence of acquired resistance to anti-HER2 therapy, novel agents were investigated, including antibody-drug conjugates (ADCs). ADCs represent an emerging class of anticancer agents consisting of a humanized monoclonal antibody bounded to a cytotoxic drug by a molecular linker. HER2-positive mBC represents the first solid tumor in which ADCs, like Trastuzumab emtansine (T-DM1) and Trastuzumab deruxtecan (T-DXd), demonstrated to improve clinical outcomes compared to prior standards of care. Nonetheless, despite their effectiveness, resistance to T-DM1 and T-DXd still occurs in most of the patients treated with these ADCs, warranting an improved understanding of the mechanisms underlying resistance. This review aims to describe the emerging mechanisms of resistance to ADCs targeting HER2, highlighting the potential strategies to overcome resistance and further improve clinical outcomes of patients with metastatic breast cancer. Abstract The treatment of HER2-positive metastatic breast cancer (mBC) with Trastuzumab emtansine (T-DM1) and Trastuzumab deruxtecan (T-DXd), two antibody-drug conjugates (ADCs) targeting HER2, is burdened by progression of disease related to the acquisition of mechanisms of resistance. Resistance to T-DM1 is caused by the decrease of HER2 expression, the alteration of intracellular trafficking, the impairment of lysosome functions, the drug expulsion through efflux pumps and the activation of alternative signal pathways. Instead, the decrease of HER2 expression and SLX4 loss of function mutations represent the first evidences of mechanisms of resistance to T-DXd, according to the results of DAISY trial. Several strategies are under evaluation to overcome resistances to anti-HER2 ADCs and improve clinical outcomes in patients progressing on these agents: combinations with tyrosine kinase inhibitors, statins, immune checkpoint inhibitors and synthetic DNA-damaging agents are emerging as promising approaches. Furthermore, novel anti-HER2 ADCs with innovative structures and mechanisms of action are in development, in the attempt to further improve the activity and tolerability of currently available agents.
microRNAs (miRNAs) in Glioblastoma Multiforme (GBM)—Recent Literature Review

Glioblastoma multiforme (GBM) is the most common, malignant, poorly promising primary brain tumor. GBM is characterized by an infiltrating growth nature, abundant vascularization, and a rapid and aggressive clinical course. For many years, the standard treatment of gliomas has invariably been surgical treatment supported by radio- and chemotherapy. Due to the location and significant resistance of gliomas to conventional therapies, the prognosis of glioblastoma patients is very poor and the cure rate is low. The search for new therapy targets and effective therapeutic tools for cancer treatment is a current challenge for medicine and science. microRNAs (miRNAs) play a key role in many cellular processes, such as growth, differentiation, cell division, apoptosis, and cell signaling. Their discovery was a breakthrough in the diagnosis and prognosis of many diseases. Understanding the structure of miRNAs may contribute to the understanding of the mechanisms of cellular regulation dependent on miRNA and the pathogenesis of diseases underlying these short non-coding RNAs, including glial brain tumors. This paper provides a detailed review of the latest reports on the relationship between changes in the expression of individual microRNAs and the formation and development of gliomas. The use of miRNAs in the treatment of this cancer is also discussed.
Interface roughness scattering in GaAs/AlAs quantum wells

We study experimentally and theoretically the influence of interface roughness on the mobility of two‐dimensional electrons in modulation‐doped AlAs/GaAs quantum wells. It is shown that interface roughness scattering is the dominant scattering mechanism in thin quantum wells with a well thickness Lw<60 A, where electron mobilities are proportional to L6w, reaching 2×103 cm2/V s at Lw∼55 A. From detailed comparison between theory and experiment, it is determined that the ‘‘GaAs‐on‐AlAs’’ interface grown by molecular beam epitaxy has a roughness with the height of 3–5 A and a lateral size of 50–70 A.
Synthesis, structure, and magnetic behavior of nanoparticles of cubic ZnMnO3

Synthesis and nature of magnetism in ZnMnO3 nanoparticles with cubic spinel structure (a = 8.369 A and size D ≃ 25 nm) are reported. Magnetization M vs. H and M vs. T data yield ferrimagnetism with TN ≃ 20 K, μ/Mn = 4.46 μB, MS ≃ 18.5 emu/g, and a transition at TS ≃ 7 K. For T < TN, coercivity and exchange-bias approach zero at TN with anomaly at TS. Using magnetic data and simulations, structure of [Zn2+][Zn1/32+Mn2/33+Mn2/34+□1/3]O11/3 with antiparallel moments of Mn4+ and Mn3+ is proposed.
AN ATTEMPT TO DETECT NEUTRAL HYDROGEN IN PLANETARY NEBULAE

Abstract : Six planetary nebulae were observed at the frequency of the 21 cm hydrogen line in an attempt to detect absorption of the thermal radio emission in neutral hydrogen in the outer parts of the nebulae. No evidence of such neutral gas was detected, and in two cases an upper limit of 0.12 solar mass can be placed on the HI mass if the observations are interpreted in terms of a spherically-symmetrical model and the temperature of the neutral gas is = or < 100 degrees K. (Author)