Miracle-dz/UniFAR-FTUs huggingface dataset:
Analysis of Microheat Pipes With Axial Conduction in the Solid Wall

A one-dimensional, steady-state model of a triangular microheat pipe (MHP) is developed, with the main purpose of investigating the thermal effects of the solid wall on the heat transport capacity of an MHP. The energy equation of the solid wall is solved analytically to obtain the axial temperature distribution, the average of which over the entire length of the MHP is simply its operating temperature. Next, the liquid phase is coupled with the solid wall by a heat transfer coefficient. Then, the continuity, momentum, and energy equations of the liquid and vapor phases are, together with the Young― Laplace equation, solved numerically to yield the heat and fluid ftow characteristics of the MHP. The heat transport capacity and the associated optimal charge level of the working fluid are predicted for different operating conditions. Comparison between the models with and without a solid wall reveals that the presence of the solid wall induces a change in the phase change heat transport by the working fluid, besides facilitating axial heat conduction in the solid wall. The analysis also highlights the effects of the thickness and thermal conductivity of the solid wall on its axial temperature distribution. Finally, while the contribution of the thermal effects of the solid wall on the heat transport capacity of the MHP is usually not dominant, it is, nevertheless, not negligible either.
Risk factors associated with witnessing cyberbullying in primary education

Cyberbullying is a harmful and intentional act of an aggressor/s to a victim, through technology, which causes an imbalance of power. The role of bystanders is key for early intervention in the phenomenon. The objective of the study is to detect risk factors associated with cyberbystanders in Primary Education based on individual variables related to the use of technologies (number of technologies, type of technology, frequency, purpose of use, time slot
High-Breakdown-Voltage and Low-Specific-on-Resistance GaN p–n Junction Diodes on Free-Standing GaN Substrates Fabricated Through Low-Damage Field-Plate Process

In this letter, we describe the characteristics of Gallium Nitride (GaN) p–n junction diodes fabricated on free-standing GaN substrates with low specific on-resistance Ron and high breakdown voltage VB. The breakdown voltage of the diodes with the field-plate (FP) structure was over 3 kV, and the leakage current was low, i.e., in the range of 10-4 A/cm2. The specific on-resistance of the diodes of 60 µm diameter with the FP structure was 0.9 mΩ·cm2. Baliga's figure of merit (VB2/Ron) of 10 GW/cm2 is obtained. Although a certain number of dislocations were included in the device, these excellent results indicated a definite availability of this material system for power-device applications.
An analysis of undergraduate core material in the light of hand-held computer algebra systems

This study investigates how hand-held computer algebra systems may be used to complete undergraduate mathematics course work tasks. Core university mathematics courses are examined in detail using a question classification scheme that describes the style of a question, rather than the syllabus topic. The majority of the tasks examined could be completed directly using the device. Surreptitious use of the hand-held device would subvert the intentions of the course designer.
A bifurcation study of laminar flow in a curved tube of rectangular cross-section

The spiralling flow within a curved tube of rectangular cross-section normally forms two distinct cells in the plane of the cross-section, but a transition to a different, four-cell flow is known to occur at a critical value of the axial pressure gradient. This paper shows that, for a square cross-section, the transition is a result of a complex structure of multiple, symmetric and asymmetric solutions. The structure is revealed by solving extended systems of equations for steady-state, fully developed, laminar flow, in a finite-element approximation, to locate exactly the positions of singular points. Continuation methods are used to trace the paths of these points as the aspect ratio and radius of curvature vary. For a square cross-section, multiple, symmetric flows of both two and four cells are found in two distinct ranges of axial pressure gradient q. In addition, a pair of asymmetric solutions arise from a symmetry-breaking bifurcation point on the primary flow branch. The paths of limit points and symmetry-breaking bifurcation points are obtained as the aspect ratio γ varies, and a transcritical bifurcation point is found at γ = 1.43. For larger aspect ratios the secondary four-cell branch is disconnected from that of the primary two-cell flow. The bifurcation set in the two parameters q and γ has a complex structure, with a number of higher-order singularities; in particular, the path of limit points is found to cross in the manner of an unfolded swallowtail catastrophe. A stability analysis shows that all multiple solutions except the two-cell type are unstable with respect to either symmetric or antisymmetric perturbations. For values of the aspect ratio less than 1.43 there is a range of axial pressure gradients for which there is no stable flow. The critical Dean numbers of the singular points are found to vary strongly at small values of radius of curvature β, but the bifurcation set remains qualitatively the same. Previous work is interpreted in the light of the present results.
Suzaku observation of NGC 3516: complex absorption and the broad and narrow Fe K lines

We present results from a 150 ksec Suzaku observation of the Seyfert 1 NGC 3516 in October 2005. The source was in a relatively highly absorbed state. Our best-fit model is consistent with partial covering by a lowly-ionized absorber with a column density near 5x10(exp 22) cm(exp -2) and with a covering fraction 96-100 percent. Narrow K-shell absorption features due to He- and H-like Fe confirm the presence of a high-ionization absorbing component as well. A broad Fe K(alpha) diskline is required in all fits, even after the complex absorption is taken into account; an additional partial-covering component is an inadequate substitute for the continuum curvature associated with the broad line. The narrow Fe Ka line at 6.4 keV is resolved, yielding a velocity width commensurate with the optical Broad Line Region. The strength of the Compton reflection hump suggests a contribution mainly from the broad Fe line origin. We include in our model soft band emission lines from He- and H-like ions and radiative recombination lines, consistent with photo-ionization, though a small contribution from collisional ionization is possible.
Hubble Space Telescope Imaging in the Chandra Deep Field-South. I. Multiple Active Galactic Nucleus Populations

We present preliminary results from imaging three Hubble Space Telescope (HST) Wide Field Planetary Camera 2 fields in V and I within the Chandra Deep Field-South (CDF-S). HST's sensitivity and resolution are sufficient to reveal optical counterparts for 24 of the 26 CDF-S X-ray sources detected in the 300 ks X-ray catalog and determine the morphologies of most of these. We find that the X-ray sources comprise two apparently distinct populations of optical candidates: one optically faint (I ≳ 24), with V-I colors consistent with the I > 24 field population, and the other significantly brighter (I ≲ 22), with colors redder than the I < 22 field population. More than two-thirds of the X-ray source counterparts are resolved galaxies. The brighter sources are mostly active galactic nuclei (AGNs) based on their high X-ray luminosity. The optically resolved sources in the brighter population have a very narrow range of V-I color and appear to be a mix of both late- and early-type morphologies at low to moderate redshift. We show that the second population, with fainter optical counterparts, can be explained as higher redshift type 2 AGNs.
Dehn surgeries on periodic links

We consider orientable closed connected 3‐manifolds obtained by Dehn surgeries with rational coefficients along the components of certain periodic links. These manifolds extend many classes of (hyperbolic) manifolds considered by several authors (see the references). We find geometric presentations of the fundamental group of such manifolds, and study some covering properties of them. Then we obtain results on their geometric structures in many cases. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
High power terahertz quantum cascade lasers with symmetric wafer bonded active regions

We increased the active region/waveguide thickness of terahertz quantum cascade lasers with semi-insulating surface plasmon waveguides by stacking two symmetric active regions on top of each other, via a direct wafer bonding technique. In this way, we enhance the generated optical power in the cavity and the mode confinement. We achieved 470 mW peak output power in pulsed mode from a single facet at a heat sink temperature of 5 K and a maximum operation temperature of 122 K. Furthermore, the devices show a broad band emission spectrum over a range of 420 GHz, centered around 3.9 THz.
Unveiling locally linearly polarized vector fields with broken axial symmetry

We explore how the focusing of axial-symmetry-broken vector fields is associated with a sector aperture whose apex coincides with the field axis. Its focused field is azimuthally split into a pair of orthogonal right- and left-handed circularly polarized partial rings which are rotated by angles of {+-}{pi}/2 with respect to the input vector field carrying no orbital angular momentum (OAM) and no spin angular momentum (SAM), respectively. Each member of the pair of partial rings carries not only the opposite OAM but also the opposite SAM. We unveil the underlying physics behind such an effect.
AC magnetization losses in striated YBCO-123/Hastelloy coated conductors

In this work we present experimental results of reductions in AC magnetization losses due to a striation process in YBCO-123/Hastelloy coated conductors. The measurements were carried out in a sinusoidally varying external magnetic field, with amplitudes up to 100 mT, in a frequency range of 8.5–85.4 Hz, and at a temperature of 77 K. The field was oriented perpendicularly to the face of the tapes. Sample tapes were successively patterned into the form of narrow parallel strips, by means of a photoresist lithography and chemical wet etching technique. Experimental results are discussed in the framework of existing theoretical models for energy dissipation in thin films in perpendicular AC magnetic fields.
An Example of a Functional which is Weakly Lower Semicontinuous on $W_0^{1,p}$ for every $p>2$ but not on $H_0^1$

In this note we give an example of a functional which is defined and coercive on H1 0 (Ω), which is sequentially weakly lower semicontinuous on W 1,p 0 (Ω) for every p > 2, but which is not sequentially lower semicontinuous on H1 0 (Ω). This functional is non local.
Protein C and S levels in patients with Thalassemia intermedia

This study was conducted to assess the level of proteins C and S in patients with thalassemia intermedia from the Thalassemia Center in Erbil, Iraq. This study aimed to evaluate protein C and S levels in patients with β-thalassemia intermedia and correlate them to different clinical and laboratory parameters. This comprehensive descriptive case-control study was conducted in 2021. Twenty-three thalassemia intermedia patients were recruited. After the participants' demographic data were recorded, plasma levels of both proteins were measured. The acquired files were examined for the 23 patients studied, 48% of whom were female. The mean age of the patients was 16.32 years. The findings show that the proportion of protein C in males was greater than in females, while this percentage contrasts when compared with protein S (ranging between 89–99% and 85–96%, respectively). Concerning age, these two types of protein in children have more value compared to older ages. Only seven people had less than 1,000 ferritins, while the others had higher values. A decrease in proteins C and S was observed in the thalassemia intermediate compared to the control group. There was a significant relationship between the decreased protein C and S levels with splenectomy. Given the significant reduction in protein C and S levels among patients with thalassemia intermediate compared to the control group, there is an increased risk of thromboembolic events in patients with thalassemia intermediate.
The prevalence of high-risk human papillomavirus genotypes and related risk factors among Iranian women

Human papillomavirus (HPV) infection, which often includes high-risk genotype infection, is one of the leading causes of cervical cancer. This cross-sectional research included 503 Iranian women referred to the gynecology clinic of Kamali Hospital in Karaj, Iran, for routine cervical cancer screening between 2020 and 2021. Cervical specimens were collected from all participants with a special brush and transported to the laboratory for cervical cytology diagnosis. Overall HPV incidence among Iranian women was 39.96%, of which 23.06% had high-risk HPV genotypes and 9.7% had low-risk HPV types. The risk associated with HR-HPV types was considerably associated with employment and marital status.
Hospital-based antimicrobial stewardship, India

Abstract Objective To establish a framework for implementing antimicrobial stewardship in Indian tertiary care hospitals, and identify challenges and enablers for implementation. Methods Over 2018–2021 the Indian Council of Medical Research followed a systematic approach to establish a framework for implementation of antimicrobial stewardship in Indian hospitals. We selected 20 Indian tertiary care hospitals to study the feasibility of implementing a stewardship programme. Based on a questionnaire to lead physicians before and after the intervention, we assessed progress using a set of process and outcome indicators. In a qualitative survey we identified enablers and barriers to implementation of antimicrobial stewardship. Findings We found an improvement in various antimicrobial stewardship implementation indicators in the hospitals after the intervention. All 20 hospitals conducted monthly point prevalence analysis of cultures compared with three hospitals before the intervention. The number of hospitals that initiated formulary restrictions increased from two to 12 hospitals and the number of hospitals that started practising prescription audit and feedback increased from six to 16 hospitals. Respondents in 15 hospitals expressed their willingness to expand the coverage of antimicrobial stewardship implementation to other wards and intensive care units. Six hospitals were willing to recruit the permanent staff needed for antimicrobial stewardship activities. Conclusion Antimicrobial stewardship can be implemented in Indian tertiary hospitals with reasonable success, subject to institutional support, availability of trained manpower and willingness of hospitals to support antimicrobial stewardship-related educational and training activities.
Magnetic Shielding of the Channel Walls in a Hall Plasma Accelerator

In a qualification life test of a Hall thruster it was found that the erosion of the acceleration channel practically stopped after ∼5600 h. Numerical simulations using a two-dimensional axisymmetric plasma solver with a magnetic field-aligned mesh reveal that when the channel receded from its early-in-life to its steady-state configuration the following changes occurred near the wall: (1) reduction of the electric field parallel to the wall that prohibited ions from acquiring significant impact kinetic energy before entering the sheath, (2) reduction of the potential fall in the sheath that further diminished the total energy ions gained before striking the material, and (3) reduction of the ion number density that decreased the flux of ions to the wall. All these changes, found to have been induced by the magnetic field, constituted collectively an effective shielding of the walls from any significant ion bombardment. Thus, we term this process in Hall thrusters “magnetic shielding. ”
Comparison Results for Gromov-Wasserstein and Gromov-Monge Distances

Inspired by the Kantorovich formulation of optimal transport distance between probability measures on a metric space, Gromov-Wasserstein (GW) distances comprise a family of metrics on the space of isomorphism classes metric measure spaces. In previous work, the authors introduced a variant of this construction which was inspired by the original Monge formulation of optimal transport; elements of the resulting family are referred to Gromov-Monge (GM) distances. These GM distances, and related ideas, have since become a subject of interest from both theoretical and applications-oriented perspectives. In this note, we establish several theoretical properties of GM distances, focusing on comparisons between GM and GW distances. In particular, we show that GM and GW distances are equal for non-atomic mm-spaces. We also consider variants of GM distance, such as a Monge version of Sturm's $L_p$-transportion distance, and give precise comparisons to GW distance. Finally, we establish bi-H\"{o}lder equivalence between GM distance and an isometry-invariant Monge optimal transport distance between Euclidean metric measure spaces that has been utilized in shape and image analysis applications.
Hungry Hungry Hippos: Towards Language Modeling with State Space Models

State space models (SSMs) have demonstrated state-of-the-art sequence modeling performance in some modalities, but underperform attention in language modeling. Moreover, despite scaling nearly linearly in sequence length instead of quadratically, SSMs are still slower than Transformers due to poor hardware utilization. In this paper, we make progress on understanding the expressivity gap between SSMs and attention in language modeling, and on reducing the hardware barrier between SSMs and attention. First, we use synthetic language modeling tasks to understand the gap between SSMs and attention. We find that existing SSMs struggle with two capabilities: recalling earlier tokens in the sequence and comparing tokens across the sequence. To understand the impact on language modeling, we propose a new SSM layer, H3, that is explicitly designed for these abilities. H3 matches attention on the synthetic languages and comes within 0.4 PPL of Transformers on OpenWebText. Furthermore, a hybrid 125M-parameter H3-attention model that retains two attention layers surprisingly outperforms Transformers on OpenWebText by 1.0 PPL. Next, to improve the efficiency of training SSMs on modern hardware, we propose FlashConv. FlashConv uses a fused block FFT algorithm to improve efficiency on sequences up to 8K, and introduces a novel state passing algorithm that exploits the recurrent properties of SSMs to scale to longer sequences. FlashConv yields 2$\times$ speedup on the long-range arena benchmark and allows hybrid language models to generate text 2.4$\times$ faster than Transformers. Using FlashConv, we scale hybrid H3-attention language models up to 2.7B parameters on the Pile and find promising initial results, achieving lower perplexity than Transformers and outperforming Transformers in zero- and few-shot learning on a majority of tasks in the SuperGLUE benchmark.
Langevin algorithms for very deep Neural Networks with application to image classification

Training a very deep neural network is a challenging task, as the deeper a neural network is, the more non-linear it is. We compare the performances of various preconditioned Langevin algorithms with their non-Langevin counterparts for the training of neural networks of increasing depth. For shallow neural networks, Langevin algorithms do not lead to any improvement, however the deeper the network is and the greater are the gains provided by Langevin algorithms. Adding noise to the gradient descent allows to escape from local traps, which are more frequent for very deep neural networks. Following this heuristic we introduce a new Langevin algorithm called Layer Langevin, which consists in adding Langevin noise only to the weights associated to the deepest layers. We then prove the benefits of Langevin and Layer Langevin algorithms for the training of popular deep residual architectures for image classification.
Geometry of CMC surfaces of finite index

Abstract Given r 0 > 0 {r}_{0}\gt 0 , I ∈ N ∪ { 0 } I\in {\mathbb{N}}\cup \left\{0\right\} , and K 0 , H 0 ≥ 0 {K}_{0},{H}_{0}\ge 0 , let X X be a complete Riemannian 3-manifold with injectivity radius Inj ( X ) ≥ r 0 \hspace{0.1em}\text{Inj}\hspace{0.1em}\left(X)\ge {r}_{0} and with the supremum of absolute sectional curvature at most K 0 {K}_{0} , and let M ↬ X M\hspace{0.33em}\looparrowright \hspace{0.33em}X be a complete immersed surface of constant mean curvature H ∈ [ 0 , H 0 ] H\in \left[0,{H}_{0}] and with index at most I I . We will obtain geometric estimates for such an M ↬ X M\hspace{0.33em}\looparrowright \hspace{0.33em}X as a consequence of the hierarchy structure theorem. The hierarchy structure theorem (Theorem 2.2) will be applied to understand global properties of M ↬ X M\hspace{0.33em}\looparrowright \hspace{0.33em}X , especially results related to the area and diameter of M M . By item E of Theorem 2.2, the area of such a noncompact M ↬ X M\hspace{0.33em}\looparrowright \hspace{0.33em}X is infinite. We will improve this area result by proving the following when M M is connected; here, g ( M ) g\left(M) denotes the genus of the orientable cover of M M : (1) There exists C 1 = C 1 ( I , r 0 , K 0 , H 0 ) > 0 {C}_{1}={C}_{1}\left(I,{r}_{0},{K}_{0},{H}_{0})\gt 0 , such that Area ( M ) ≥ C 1 ( g ( M ) + 1 ) {\rm{Area}}\left(M)\ge {C}_{1}\left(g\left(M)+1) . (2) There exist C > 0 C\gt 0 , G ( I ) ∈ N G\left(I)\in {\mathbb{N}} independent of r 0 , K 0 , H 0 {r}_{0},{K}_{0},{H}_{0} , and also C C independent of I I such that if g ( M ) ≥ G ( I ) g\left(M)\ge G\left(I) , then Area ( M ) ≥ C ( max 1 , 1 r 0 , K 0 , H 0 ) 2 ( g ( M ) + 1 ) {\rm{Area}}\left(M)\ge \frac{C}{{\left(\max \left\{1,\frac{1}{{r}_{0}},\sqrt{{K}_{0}},{H}_{0}\right\}\right)}^{2}}\left(g\left(M)+1) . (3) If the scalar curvature ρ \rho of X X satisfies 3 H 2 + 1 2 ρ ≥ c 3{H}^{2}+\frac{1}{2}\rho \ge c in X X for some c > 0 c\gt 0 , then there exist A , D > 0 A,D\gt 0 depending on c , I , r 0 , K 0 , H 0 c,I,{r}_{0},{K}_{0},{H}_{0} such that Area ( M ) ≤ A {\rm{Area}}\left(M)\le A and Diameter ( M ) ≤ D {\rm{Diameter}}\left(M)\le D . Hence, M M is compact and, by item 1, g ( M ) ≤ A / C 1 − 1 g\left(M)\le A\hspace{0.1em}\text{/}\hspace{0.1em}{C}_{1}-1 .
Statistical Analysis of Plasma Dynamics in Gyrokinetic Simulations of Stellarator Turbulence

A geometrical method for assessing stochastic processes in plasma turbulence is investigated in this study. The thermodynamic length methodology allows using a Riemannian metric on the phase space; thus, distances between thermodynamic states can be computed. It constitutes a geometric methodology to understand stochastic processes involved in, e.g., order–disorder transitions, where a sudden increase in distance is expected. We consider gyrokinetic simulations of ion-temperature-gradient (ITG)-mode-driven turbulence in the core region of the stellarator W7-X with realistic quasi-isodynamic topologies. In gyrokinetic plasma turbulence simulations, avalanches, e.g., of heat and particles, are often found, and in this work, a novel method for detection is investigated. This new method combines the singular spectrum analysis algorithm with a hierarchical clustering method such that the time series is decomposed into two parts: useful physical information and noise. The informative component of the time series is used for the calculation of the Hurst exponent, the information length, and the dynamic time. Based on these measures, the physical properties of the time series are revealed.