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At least 1,315 records · Page 73
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Extended Hamiltonians and shift, ladder functions and operators

In recent years, many natural Hamiltonian systems, classical and quantum, with constants of motion of high degree, or symmetry operators of high order, have been found and studied. Most of these Hamiltonians, in the classical case, can be included in the family of extended Hamiltonians, geometrically characterized by the structure of warped manifold of their configuration manifold. For the extended Hamiltonians, the characteristic constants of motion of high degree are polynomial in the momenta of determined form. We consider here a different form of the constants of motion, based on the factorization procedure developed for systems of two degrees of freedom by S. Kuru, J. Negro and others. We show that an important subclass of the extended Hamiltonians, with arbitrary dimension, admits factorized constants of motion and we determine their expression. The classical constants can be polynomial or non-polynomial in the momenta, but the factorization procedure allows, in a type of extended Hamiltonians, their quantization via shift and ladder operators, for systems of any finite dimension. - Highlights: • A factorization procedure is proposed for first integrals of high degree of extended Hamiltonian systems. • The extended Hamiltonians are defined on warped manifolds of any finite dimension. • Polynomial first integrals are quantized into factorized polynomial symmetry operators of Laplace–Beltrami-type quantum Hamiltonians.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2021

Statistical analysis of spatial distribution of pores in metal additive manufacturing

We report mechanical properties of additively manufactured parts are sensitive to the presence of pores form during the manufacturing process. The impact of pores on the mechanical performance has been investigated extensively with respect to different parameters, such as pore volume fraction, shape, and size. However, statistical investigations focusing on the relationships between the spatial distribution of pores and process parameters; and consequently, the performance of the manufactured parts are scattered and limited. Also, these sparse investigations usually suffer from an ambiguous definition of terminologies. For instance, the required criteria to consider a point pattern as complete spatial randomness (CSR) are generally not clarified. Moreover, no numerical formalism is yet developed to show how much the observed spatial results are statistically significant. To address these shortcomings, the statistical definition of CSR in a point pattern and the procedure to quantitatively determine the deviation of a pattern from CSR were discussed. The explained statistical approach was used to investigate the effect of scanning speed parameter on the spatial distribution of gas pores in laser powder bed fusion manufactured stainless steel parts. Furthermore, and to highlight the impact of the spatial distribution of pores on mechanical properties, fatigue performances of parts with clustered and randomly distributed pores were simulated by finite element analysis. It is shown that by reducing the scanning speed, the spatial distribution of gas pores deviated more from CSR, and correspondingly fatigue performance deteriorated.

36 MATERIALS SCIENCE↗
NASA NTRS1993

A new flux conserving Newton's method scheme for the two-dimensional, steady Navier-Stokes equations

A new numerical method is developed for the solution of the two-dimensional, steady Navier-Stokes equations. The method that is presented differs in significant ways from the established numerical methods for solving the Navier-Stokes equations. The major differences are described. First, the focus of the present method is on satisfying flux conservation in an integral formulation, rather than on simulating conservation laws in their differential form. Second, the present approach provides a unified treatment of the dependent variables and their unknown derivatives. All are treated as unknowns together to be solved for through simulating local and global flux conservation. Third, fluxes are balanced at cell interfaces without the use of interpolation or flux limiters. Fourth, flux conservation is achieved through the use of discrete regions known as conservation elements and solution elements. These elements are not the same as the standard control volumes used in the finite volume method. Fifth, the discrete approximation obtained on each solution element is a functional solution of both the integral and differential form of the Navier-Stokes equations. Finally, the method that is presented is a highly localized approach in which the coupling to nearby cells is only in one direction for each spatial coordinate, and involves only the immediately adjacent cells. A general third-order formulation for the steady, compressible Navier-Stokes equations is presented, and then a Newton's method scheme is developed for the solution of incompressible, low Reynolds number channel flow. It is shown that the Jacobian matrix is nearly block diagonal if the nonlinear system of discrete equations is arranged approximately and a proper pivoting strategy is used. Numerical results are presented for Reynolds numbers of 100, 1000, and 2000. Finally, it is shown that the present scheme can resolve the developing channel flow boundary layer using as few as six to ten cells per channel width, depending on the Reynolds number.

Scott, James R.↗
DOE OSTI2023

Defect‐Free Sound Insulator Using Single Metal‐Based Friction Stir Process Array

Metals are excellent conductors for phonon transportation such as vibration, sound, and heat. Generally, metal sound insulators require multimaterial structure or defects and unimetal sound insulators are challenging. Therefore, a design of a defect-free sound insulator made by single alloys with multiple friction stir processes (FSPs) is proposed. Periodic friction stir processing can induce superlattice-like local mechanical properties’ modifications. By experimental acoustic characterization, it is observed that FSP can introduce clear acoustic–elastic property contrast on an aluminum plate by the presence of stir zone and heat-affected zones. In numerical simulations, the signature FSP-induced property profile is periodically and parallelly arranged on a long aluminum plate. The transmission gap frequencies are present on the frequency spectrum with the sound propagation direction perpendicular to the FSP paths. Disorder offsets on FSP periodicity are further introduced. Anderson localization is found on a resonance frequency, which provides −11 dB sound reduction by an exponential decay. Due to the finite design length, the slight disorder can also enhance sound insulation in the periodic transmission gap frequency. In conclusion, with analysis and comparison with different configurations, the best performance in the models can achieve −30 dB sound insulation in the 350 mm-long aluminum alloy plate with 14 parallel FSPs.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Laser propagation and soliton generation in strongly magnetized plasmas

The propagation characteristics of various laser modes with different polarization, as well as the soliton generation in strongly magnetized plasmas are studied numerically through one-dimensional (1D) particle-in-cell (PIC) simulations and analytically by solving the laser wave equation. PIC simulations show that the laser heating efficiency substantially depends on the magnetic field strength, the propagation modes of the laser pulse and their intensities. Generally, large amplitude laser can efficiently heat the plasma with strong magnetic field. Theoretical analyses on the linear propagation of the laser pulse in both under-dense and over-dense magnetized plasmas are well confirmed by the numerical observations. Most interestingly, it is found that a standing or moving soliton with frequency lower than the laser frequency is generated in certain magnetic field strength and laser intensity range, which can greatly enhance the laser heating efficiency. The range of magnetic field strength for the right-hand circularly polarized (RCP) soliton formation with high and low frequencies is identified by solving the soliton equations including the contribution of ion's motion and the finite temperature effects under the quasi-neutral approximation. In the limit of immobile ions, the RCP soliton tends to be peaked and stronger as the magnetic field increases, while the enhanced soliton becomes broader as the temperature increases. These findings in 1D model are well validated by 2D simulations.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2025

What exactly does Bekenstein bound?

The Bekenstein bound posits a maximum entropy for matter with finite energy confined to a spatial region. It is often interpreted as a fundamental limit on the information that can be stored by physical objects. In this work, we test this interpretation by asking whether the Bekenstein bound imposes constraints on a channel's communication capacity, a context in which information can be given a mathematically rigorous and operationally meaningful definition. We study specifically the Unruh channel that describes a stationary Alice exciting different species of free scalar fields to send information to an accelerating Bob, who is confined to a Rindler wedge and exposed to the noise of Unruh radiation. We show that the classical and quantum capacities of the Unruh channel obey the Bekenstein bound that pertains to the decoder Bob. In contrast, even at high temperatures, the Unruh channel can transmit a significant number of zero-bits , which are quantum communication resources that can be used for quantum identification and many other primitive protocols. Therefore, unlike classical bits and qubits, zero-bits and their associated information processing capability are generally not constrained by the Bekenstein bound. However, we further show that when both the encoder and the decoder are restricted, the Bekenstein bound does constrain the channel capacities, including the zero-bit capacity.

Hayden, Patrick [Stanford University, CA (United S↗
DOE OSTI2021

Extended Applications of Subgrid Representation in the 2D/1D Method

Recent efforts in MPACT have focused on improving the performance of the 2D/1D subplane implementation to help target computational performance goals. Here, we build on previous efforts that targeted the use of subgrid treatments to improve the accuracy of control rod representation, presenting three additional applications of subgrid treatments with the goal of reducing the computational burden of simulations. These subgrid applications include treatment of spacer grids, thermal feedback, and axial reflector material representation. With these approaches, a single method of characteristics (MOC) plane can contain several different materials axially that are represented explicitly via subgrids on the coarse mesh finite difference (CMFD) mesh but are axially homogenized on the MOC mesh. This allows for a substantial reduction in the number of MOC planes needed in the calculation through the introduction of an approximate treatment, particularly with regard to the self-shielded cross sections and MOC-informed radial current coupling coefficients in CMFD. Several test problems ranging from single rod to quarter core are used to assess the solution accuracy and performance of these various subgrid representations. Overall, the accuracy of the approximations seems very reasonable, with extremely small differences in eigenvalue observed and maximum pin power errors in the 0.5% to 1.0% range. Several cases show substantial value in the compromise between accuracy and computational performance. Others highlight the new computational hurdles that future research will aim to resolve.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
NASA NTRS2012

A Comparison of Filter-based Approaches for Model-based Prognostics

Model-based prognostics approaches use domain knowledge about a system and its failure modes through the use of physics-based models. Model-based prognosis is generally divided into two sequential problems: a joint state-parameter estimation problem, in which, using the model, the health of a system or component is determined based on the observations; and a prediction problem, in which, using the model, the stateparameter distribution is simulated forward in time to compute end of life and remaining useful life. The first problem is typically solved through the use of a state observer, or filter. The choice of filter depends on the assumptions that may be made about the system, and on the desired algorithm performance. In this paper, we review three separate filters for the solution to the first problem: the Daum filter, an exact nonlinear filter; the unscented Kalman filter, which approximates nonlinearities through the use of a deterministic sampling method known as the unscented transform; and the particle filter, which approximates the state distribution using a finite set of discrete, weighted samples, called particles. Using a centrifugal pump as a case study, we conduct a number of simulation-based experiments investigating the performance of the different algorithms as applied to prognostics.

prognostics↗
DOE OSTI2022

Progress on Demonstration of a MOOSE-Based Coupled Capability for Hot Channel Factors in Fast Reactors

Hot channel factors (HCFs) are computed values that account for the impact on predicted peak fuel, cladding, and coolant temperatures due to uncertainties in the as-built reactor’s material properties and geometry as well as uncertainties due to modeling approximations. Reduction in computed HCF values via reduction or elimination of modeling approximations may translate to significant economic savings if the reactor power can be raised due to the extra temperature margin gained. While limited historical datasets exist for sodium-cooled fast reactors (SFRs), there are no available HCF data for lead-cooled fast reactors (LFRs) outside of work generated previously within NEAMS. The computation of HCFs involves insights from reactor physics, thermal fluids and heat conduction calculations to determine how the peak temperatures respond to various uncertainties in the design. Due to the significant advantages for multi-physics coupling offered by the MOOSE framework, Griffin (MOOSE-based reactor physics code), MOOSE Heat Conduction Module, and Cardinal (MOOSE-wrapped multi-physics application which includes the NekRS thermal fluids code) are being coupled together using the MOOSE MultiApp System to develop a highfidelity multi-physics modeling capability for HCF simulations. This high-fidelity coupling workflow may also be beneficial for other fast reactor applications in the future. In previous work, Griffin and NekRS were individually assessed to ensure the necessary capabilities were in place. This work describes initial efforts to couple the codes (including folding in the MOOSE Heat Conduction Module) and determining the workflow for the perturbed calculations which will leverage the Stochastic Tools Module (STM). To our knowledge, this is the first coupling of Griffin and NekRS as well as the first exploratory use of Stochastic Tools Module for Cardinal. In this report, the neutronics code Griffin, the heat conduction solver in MOOSE, and the MOOSE-wrapped application containing NekRS (Cardinal) are linked together to demonstrate the coupled capability. Griffin and Cardinal are linked dynamically by specifying shared libraries. Different coupling hierarchies are tested for selecting the most appropriate coupling strategy. A coupling scheme is selected based on the efficiency of calculation and ease of data communication. Multiple tests are performed to choose suitable mesh structure, model configurations, scheme setup and boundary conditions to avoid loss of energy due to data interpolation between different modules or weak imposition of fluxes in finite element codes. Computational experiments are performed to study the tolerance control of each type of iteration to avoid false convergence. The coupled capability is demonstrated in both single pin and 7-pin models based on LFR materials and geometry. The study finds that the use of too large a time step size in the heat conduction module can lead to temperature oscillation even though the heat conduction equation does not have a time-derivative kernel, but only the time-dependent boundary condition. A 7-pin model without duct region achieved good convergence in the coupled calculation while a 7 pin model with duct region experienced data communication issues which need to be resolved.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2016

Supplement to “Torsional oscillations of a magnetar with a tangled magnetic field” (2016, ApJL, 823, L1)

We introduce a mean-field formalism with which to study the oscillations of a neutron star or other stellar object with a dipolar magnetic field plus a topologically distinct isotropic magnetic tangle that stabilizes the field configuration. In terms of the ratio of the energy density of the tangled field to that in the dipolar component b {sub t} {sup 2}, we obtain separable equations for the eigenfunctions and eigenfrequencies for a star of uniform density. We show that finite b {sub t} {sup 2} breaks the Alfvén continuum that is supported by the dipolar component of the field into discrete normal modes, and we quantify the splitting. Assuming the estimated dipole fields of 7×10{sup 14} G in SGR 1900+14 and 2×10{sup 15} G in SGR 1806–20, and tuning b {sub t} {sup 2} to match the lowest-frequency quasi-periodic oscillations observed to accompany flares in these objects, we infer b{sub t}{sup 2}=13.3 and 0.17, respectively. The predicted spectrum is about three times denser than that observed in SGR 1900+14, and much denser in SGR 1806–20. If the dipole field of SGR 1806–20 has been overestimated, the spectrum of normal modes will be less dense. We show that for b{sub t}{sup 2}≫1, as stability considerations suggest, the crust is nearly dynamically irrelevant. Moreover, density stratification generally shifts the eigenfrequencies up by about 20%, a change that can be mostly subsumed in a uniform density model with a slightly different choice of stellar radius or mass.

79 ASTRONOMY AND ASTROPHYSICS↗
NASA NTRS1985

The non-hydrostatic figures of the terrestrial planets

Solid state creep being exponentially dependent on temperature must dominate the mechanical behavior of the mantles of terrestrial planets beneath their lithospheres. General arguments suggest that the lithospheres of the Moon and Mars are about 200 km thick; the Earth, Venus and Mercury much less. Short wavelength gravity anomalies are explained by the finite strength of the lithosphere: the lunar mascons being an example. The good correlation of the Venus and Mars gravity anomalies with topography up to spherical harmonics of degrees 10-15 is in striking contrast to the lack of correlation between the long wavelength components of the geoid and the continent-ocean distribution or even the plates. Attempts have been made to explain the former correlations by isostatic models but the depths of compensation seem implausible. Low degree harmonics of the gravity fields of the terrestrial planets as is certainly the case in the Earth must arise from the density variations driving solid state convection. In the case of Venus the less dense differentiated materials of the highlands seems to be positioned over the singular points of the convection pattern. Thus the correlated gravity field does not arise from the highlands but from the density difference in the convecting interior. In the Earth lack of correlation seems to arise from the fact that the plates have moved relative to the convection pattern the last 100 M yr.

Runcorn, S. K.↗
DOE OSTI2016

Verification of the 2D Finite Element SP3 Solutions

Method(FEM) is the free geometry handling. However many of the geometries of the nuclear engineering problems are not unstructured but rather structured, such as a hexahedral, or triangular prism. Thus, the need for the use of FEM has less portion in nuclear engineering. However it is also certain that it is very hard to exclude the possibility for use of an unstructured geometry such as a PBMR core problem, fusion blanket analysis of the source problem, another design issue with an unstructured geometry. In addition, research regarding the acceleration scheme such as Coarse Mesh Finite Difference (CMFD) showed up in nuclear engineering in recent years. By considering these facts, the FEM cannot be totally exclusive. To utilize the FEM for nuclear engineering problems, several types of assistance are needed. The first is parallelization because of its slow calculation speed. The second is an acceleration scheme. With these two types of assistance the FEM can be utilized freely in the nuclear engineering field. In this research, before conducting parallelization and acceleration, the final verification for the implementation of the up-scattering treatment with an arbitrary geometry conducted through a comparison with the McCARD solution through the well-known C5G7 2D benchmark problem. Note that the earlier work for verification of the FEM for the multi-group problem without up-scattering and with a structured geometry including a mathematical formulation has already been done. The main points that will be tested here are as follows. The first is a check of the right implementation for the multi-group problem with an up-scattering cross section from the perspectives of the multiplication factor and power. The second is the transport effect for this problem by comparing the solutions from P{sub 1} and Simplified P{sub 3}(SP{sub 3}). The third is the effectiveness of the higher order basis function for the same number of unknowns. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2018

A Generalized Backward Euler algorithm for the numerical integration of a viscous breakage model

This paper discusses the formulation and the numerical performance of a fully implicit algorithm used to integrate a rate-dependent model defined within a breakage mechanics framework. For this purpose, a Generalized Backward Euler (GBE) algorithm has been implemented according to two different linearization strategies: The former is derived by a direct linearization of the constitutive equations, while the latter introduces rate effects through a consistency parameter. Additionally, the accuracy and efficiency of the GBE algorithm have been investigated by (1) performing material point analyses and (2) solving initial boundary value problems. In both cases, the overall performance of the underlying algorithm is inspected for a range of loading rates, thus simulating comminution from slow to fast dynamic problems. As the viscous response of the breakage model can be recast through a viscous nucleus function, the presented algorithm can be considered as a general framework to integrate constitutive equations relying on the overstress approach typical of Perzyna-like viscoplastic models.

36 MATERIALS SCIENCE↗
DOE OSTI2016

Diffusion and transport in locally disordered driven lattices

We study the effect of disorder on the particle density evolution in a classical Hamiltonian driven lattice setup. If the disorder is localized within a finite sub-domain of the lattice, the emergence of strong tails in the density distribution which even increases towards larger positions is shown, thus yielding a highly non-Gaussian particle density evolution. As the key underlying mechanism, we identify the conversion between different components of the unperturbed systems mixed phase space which is induced by the disorder. Based on the introduction of individual conversion rates between chaotic and regular components, a theoretical model is developed which correctly predicts the scaling of the particle density. The effect of disorder on the transport properties is studied where a significant enhancement of the transport for cases of localized disorder is shown, thereby contrasting strongly the merely weak modification of the transport for global disorder.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2017

Convergence of the Critical Cooling Rate for Protoplanetary Disk Fragmentation Achieved: The Key Role of Numerical Dissipation of Angular Momentum

We carry out simulations of gravitationally unstable disks using smoothed particle hydrodynamics (SPH) and the novel Lagrangian meshless finite mass (MFM) scheme in the GIZMO code. Our aim is to understand the cause of the nonconvergence of the cooling boundary for fragmentation reported in the literature. We run SPH simulations with two different artificial viscosity implementations and compare them with MFM, which does not employ any artificial viscosity. With MFM we demonstrate convergence of the critical cooling timescale for fragmentation at β{sub crit}≈3. Nonconvergence persists in SPH codes. We show how the nonconvergence problem is caused by artificial fragmentation triggered by excessive dissipation of angular momentum in domains with large velocity derivatives. With increased resolution, such domains become more prominent. Vorticity lags behind density, due to numerical viscous dissipation in these regions, promoting collapse with longer cooling times. Such effect is shown to be dominant over the competing tendency of artificial viscosity to diminish with increasing resolution. When the initial conditions are first relaxed for several orbits, the flow is more regular, with lower shear and vorticity in nonaxisymmetric regions, aiding convergence. Yet MFM is the only method that converges exactly. Our findings are of general interest, as numerical dissipation via artificial viscosity or advection errors can also occur in grid-based codes. Indeed, for the FARGO code values of β{sub crit} significantly higher than our converged estimate have been reported in the literature. Finally, we discuss implications for giant planet formation via disk instability.

79 ASTRONOMY AND ASTROPHYSICS↗
NASA NTRS1990

General Rotorcraft Aeromechanical Stability Program (GRASP): Theory manual

The general rotorcraft aeromechanical stability program (GRASP) was developed to calculate aeroelastic stability for rotorcraft in hovering flight, vertical flight, and ground contact conditions. GRASP is described in terms of its capabilities and its philosophy of modeling. The equations of motion that govern the physical system are described, as well as the analytical approximations used to derive them. The equations include the kinematical equation, the element equations, and the constraint equations. In addition, the solution procedures used by GRASP are described. GRASP is capable of treating the nonlinear static and linearized dynamic behavior of structures represented by arbitrary collections of rigid-body and beam elements. These elements may be connected in an arbitrary fashion, and are permitted to have large relative motions. The main limitation of this analysis is that periodic coefficient effects are not treated, restricting rotorcraft flight conditions to hover, axial flight, and ground contact. Instead of following the methods employed in other rotorcraft programs. GRASP is designed to be a hybrid of the finite-element method and the multibody methods used in spacecraft analysis. GRASP differs from traditional finite-element programs by allowing multiple levels of substructure in which the substructures can move and/or rotate relative to others with no small-angle approximations. This capability facilitates the modeling of rotorcraft structures, including the rotating/nonrotating interface and the details of the blade/root kinematics for various types. GRASP differs from traditional multibody programs by considering aeroelastic effects, including inflow dynamics (simple unsteady aerodynamics) and nonlinear aerodynamic coefficients.

Hodges, Dewey H.↗
NASA NTRS2013

The Meteoroid Environment and Spacecraft

Difference between a meteoroid and asteroid? center dot It's all a matter of size, but there is no formal limit on the size of the biggest meteoroid or smallest asteroid. center dot Generally anything bigger than 10 meters in diameter is considered an asteroid. center dot However, the currently accepted process is that if it is detected in space and given a designation by the Minor Planet Center, it is an asteroid, no matter how big - example: 2008 TC3 is listed as an asteroid, despite being only 2 meters in diameter. Dynamical studies (e.g. Wiegert & Vaubaillon, 2008) indicate that - Helion sources originate mainly from Jupiter family comets (JFCs) - Apex sources from retrograde Halley family comets (HFCs) and long period comets. - Toroidal sources from prograde HFCs? center dot >90% of meteoroids in inner Solar System come from comets. Three main sources - Photographic (Super‐Schmidt) - Specular Radar center dot (Harvard Radio Meteor Project (HRMP) center dot CMOR center dot AMOR - HPLA center dot ALTAIR center dot Jicamarca center dot Arecibo center dot Photographic have lower number statistics and unique biases - Nighttime only - approx. V3.5 dependence on light production - Detection sensitivity is function of angular velocity center dot Radar has different biases - Ionization production also steep function of velocity (V3.5‐4) - Initial trail radius, finite velocity and diffusion attenuation center dot HPLA biases - Still controversy over how much and what sort of biases may or may not be present.

Cooke, William J.↗
DOE OSTI2016

Engineering on-chip nanoporous gold material libraries via precision photothermal treatment [Precision Photothermal Annealing of Nanoporous Gold Thin Films for the Microfabrication of a Single-ship Material Libraries]

Single-chip material libraries of thin films of nanostructured materials are a promising approach for high throughput studies of structure-property relationship in the fields of physics and biology. Nanoporous gold (np-Au), produced by an alloy corrosion process, is a nanostructured material of specific interest in both these fields. One attractive property of np-Au is its self-similar coarsening behavior by thermally induced surface diffusion. However, traditional heat application techniques for the modification of np-Au are bulk processes that cannot be used to generate a library of different pore sizes on a single chip. Laser micromachining offers an attractive solution to this problem by providing a means to apply energy with high spatial and temporal resolution. In our present study we use finite element multiphysics simulations to predict the effects of laser mode (continuous-wave vs. pulsed) and supporting substrate thermal conductivity on the local np-Au film temperatures during photothermal annealing and subsequently investigate the mechanisms by which the np-Au network is coarsening. Our simulations predict that continuous-wave mode laser irradiation on a silicon supporting substrate supports the widest range of morphologies that can be created through the photothermal annealing of thin film np-Au. Using this result we successfully fabricate a single-chip material library consisting of 81 np-Au samples of 9 different morphologies for use in increased throughput material interaction studies.

36 MATERIALS SCIENCE↗