Blackbody Research Articles

Critical Race Theory in Literature: In The Blood By Suzan-Lori Parks

This study seeks to explore the fundamental principles of Critical Race Theory (CRT) and to use it as an analytical tool in order to discuss Suzan-Lori Parks’s play, In The Blood. Through the key tenets of CRT such as the systematic racism, race as a social construct, intersectionality and power structures, it is framed a comprehensive theoretical background for a literary analysis. Relatedly, the primary focus of this study is to deeply analyze race, gender, power relations and socio-economic conditions with CRT through the playwright’s innovative representation of blackness. CRT clearly shows that racism is constructed through discriminative practices and sustained by law and institutions resulting in justification and accordingly normalization of oppression. In line with CRT’s main concerns, In The Blood embodies societal and ideological barriers and the dehumanization of black female bodies through social judgment, racial and gender discrimination, and motherhood. CRT essentially deals with how Parks reconstructs traditional narratives of guilt, shame, and femininity and claims that Hester is portrayed both as a victim of intersectional oppression and an individual struggling with the harsh conditions of life.

Designing LiDAR‐Detectable Dark‐Tone Materials with High Near‐Infrared Reflectivity for Autonomous Driving: A Comprehensive Review

AbstractAutonomous driving relies on the precise recognition of objects using light detection and ranging (LiDAR) technology, that operates at a specific wavelength of 905 nm. Black objects, such as carbon black used in vehicle coating, tend to absorb this specific wavelength significantly, which limits the performance of LiDAR sensors. To address this issue, researchers have explored creating dark‐toned materials that can be detected by LiDAR with high NIR reflectivity while maintaining a true blackness (L* < 20 based on the CIE color coordinates). These materials fall into two categories: organic and inorganic pigments. Organic pigments can be synthetically adjusted to achieve true blackness by manipulating their functional groups, but achieving high NIR reflectivity remains challenging, often requiring a bilayer structure with NIR‐reflective white base and an upper layer of organic black pigments. Additionally, the need for hydrophobic additives and resistance to degradation from sunlight further restricts their use. In the case of inorganic pigments, the desired LiDAR‐detectable properties can be obtained through careful control of their composition, structure, and morphology, allowing for single‐layer coatings with appropriate design. This review highlights recent advancements in developing organic and inorganic LiDAR‐detectable black pigments and outlines future material design strategies for autonomous vehicle systems.

Gauss-Bonnet AdS planar and spherical black hole thermodynamics and holography

Abstract In this work, we extend the study in \cite{Bilic:2022psx} incorporating the AdS/CFT duality to establish a relationship between the local temperatures (Tolman temperatures) of a large (AdS) spherical and a (AdS) planar Schwarzschild black hole near the AdS boundary considering Gauss-Bonnet curvature correction in the gravitational action. We have shown that the higher curvature corrections appear in the local temperature relationship due to the inclusion of Gauss-Bonnet term in the bulk. By transforming the metric into Fefferman-Graham form, we have calculated the energy density of the conformal fluid at the boundary. The obtained result contains finite coupling corrections which are holographically induced by the Gauss-Bonnet curvature correction in the bulk theory. Following the well known approach of fluid/gravity duality, the energy density of the conformal fluid at the boundary is then compared with the black body radiation energy density. This comparison shows that the energy density is proportional to the temperature of the conformal fluid. The temperature of the conformal fluid is then shown to be related to the Tolman temperature of the black hole which then eventually helps us to establish both the Hawking temperature and Tolman temperature relationship between large spherically symmetric and planar Schwarzschild black holes in Gauss-Bonnet gravity near the AdS boundary.

The photons and gluons sedimentation in the Svedberg ultracentrifuge

We consider the case of rotating black body (including the rotation of the black bath with gluons) where photons and gluons can perform the settling and sedimentation. The Planck formula for photons must be, in this situation, replaced by the Exner solution of the Lamm equation for photons.

Electrically charged black holes in [formula omitted]-Euler–Heisenberg theory

Drawing on the concept of the non-linear dynamics of electromagnetic fields in vacuum in terms of the Euler–Heisenberg system, a static and spherically symmetric black hole solution is derived by coupling the Euler–Heisenberg term and F(R) gravity. In applying the curvature singularity tools, the black hole solution induces a singular behaviour at the centre r=0 while exhibiting a regular shape at high distances. Using the heat capacity (CQ) and the Helmholtz free energy (F), we analyse the thermodynamic stability locally and globally. Furthermore, an investigation is conducted using class tools of Geometrothermodynamics (GTs) features such as Weinhold, Ruppeiner, Hendi–Panahiyan–Eslam–Momennia (HPEM), and Quevedo to identify phase transition points associated with heat capacity, including both physical boundary points (root of the heat capacity) and second critical phase transition points (divergent points of the heat capacity). We have even examined the relevant sparsity of Hawking radiation, showing how the black hole solution behaves as a black body at specific limits. Overall, this study enhances our knowledge of the mergers of a class of non-linear dynamics of electromagnetic fields in a vacuum within F(R) gravity by modelling black hole solutions.

Mother of All Labour: Vulnerability and Immunity in Times of Ebola

Wonkifong Ebola treatment unit was unique at the time of the outbreak that hit the Guinea in 2014. Contrary to other infrastructures run by Western workers, Wonkifong mainly employed personnel from Guinea, the Democratic Republic of Congo, and Cuba. Even so, the unit constituted a racialised landscape where proximity to white agencies granted privileges to certain groups of racialised people while excluding others. In a humanitarian infrastructure aimed at empowering knowledge of epidemics in the Global South, Black children were quarantined without their parents and left mostly unattended. After many months, former patients were hired as nannies to remedy the infrastructure’s blind spot. These women were employed to care for the children thanks to their immunity to the virus. Building on the concept of a ‘politics of life’ and exploring how these women were exploited as ‘medical superbodies’, my article sheds light on how the humanitarian infrastructure produced a gendered labour that mirrors other economies exploiting female Black bodies such as the colony or the plantation. Relying on an ethnography of practices of care and mobility within the unit, this piece underlines how the postcolonial segregation at play during the outbreak operated not strictly in terms of skin colour, but in terms of gender and closeness to white power.

The masses of open star clusters and their tidal tails and the stellar initial mass function

Unresolved binaries have a strong influence on the observed parameters of SC We quantify this influence and compute the resulting mass underestimates and MF N-body simulations of realistic SC were used to investigate the evolution of the binary population in a SC and its tidal tails. Together with an empirically gauged stellar mass-luminosity relation, the results were then used to determine how the presence of binaries changes the photometric mass and MF of the SC and its tails as deduced from observations. T1 which is the tidal tail caused by gas expulsion, contains a larger fraction of binaries than both the SC and T2 which forms after gas expulsion. Additionally T1 has a larger velocity dispersion. Using the luminosity of an unresolved binary, an observer would underestimate its mass. This bias sensitively depends on the companion masses due to the structure of the stellar mass-luminosity relation. Combining the effect of all binaries in the simulation, the total photometric mass of the SC is underestimated by 15<!PCT!>. Dark objects (black holes and neutron stars) increase the difference between the real and observed mass of the SC further. For both the SC and the tails, the observed power-law index of the MF between a stellar mass of 0.3 and 0.7 $M_ is smaller by up to 0.2 than the real one, the real IMF being steeper by this amount. This difference is larger for stars with a larger velocity dispersion or binary fraction. Since the stars formed in SC are the progenitors of the Galactic field stars, this work suggests that the binary fractions of different populations of stars in the Galactic disc will differ as a function of the velocity dispersion. However, the direction of this correlation is currently unclear, and a complete population synthesis will be needed to investigate this effect. Variations in the binary fractions of different clusters can lead to perceived variations of the deduced stellar MF

Temperature measurement in laser–metal processing using optical sensing: Radiometric calibration and validation of a multispectral camera

In laser–metal processing such as Laser-based Powder Bed Fusion of Metals (PBF-LB/M), the quality of the final product is significantly influenced by the thermal behaviour of the melt pool. Accurate temperature measurements are challenging due to high temperature gradients and rapid cooling. This study introduces Multispectral Imaging (MSI) as a highly effective thermometry technique to address these demanding conditions. MSI captures multiple bands of radiation, enabling the simultaneous determination of absolute temperature and surface emissivity. This capability is crucial for ensuring high-quality outcomes in laser–metal processing such as PBF-LB/M, contingent upon robust radiometric calibration.To enhance reliability, two radiometric calibration models were developed: an empirical model based on linear sensor data correlations and an analytical model leveraging sensor behaviour. An efficient calibration was found for both models across a range of signal-to-noise ratios in the black body calibrator, where the analytical model even performs robust under a high noise level.Additionally, the temperature accuracy in the solid-state case was tested with a thermo-mechanical simulator. Results showed that the empirical and analytical models achieved mean relative errors of 2.0% and 1.6%, respectively, outperforming the state-of-the-art. Further, laser irradiation experiments highlighted the analytical model’s ability to accurately determine the emissivity decrease during the solid-to-liquid transition, allowing for accurate melt pool temperature estimations. Conversely, the empirical model struggled to estimate temperature effectively in the liquid phase.This study not only proposed a robust methodology of MSI in temperature measurement but also confirmed the accuracy and reliability of the system, broadening the scope for further investigation into the intricate thermal dynamics involved in laser–metal interactions.

The New (White) Normal: Human Anatomy and the Naturalisation of White Bodies in British University Teaching, 1860–1910

Summary The discipline of human anatomy has often been overlooked in histories of race science in favour of comparative anatomy, anthropology, ethnography and statistics. However, understanding the historical relationship between human anatomy and race science is particularly important because of the discipline’s central role, unlike its sister disciplines, in medical education. This article begins to redress this oversight, demonstrating that human anatomy played a key role in the development of nineteenth-century race science in Britain. This article considers three main elements of ideas about racial anatomical difference: the language of racial hierarchy, anatomists’ location of racial difference within the body and the perpetuation of these ideas over time. In so doing, I argue that research into racial difference was demonstrably anatomical during the late nineteenth century, playing a key role in British anatomists’ discipline-building processes, and that these ideas were present within the classroom, influencing generations of medical students.

Possible Manifestation of Compact, Stable Dark Matter Objects in the Solar System

Possible Manifestation of Compact, Stable Dark Matter Objects in the Solar System

Behavior of Common Swift Apus apus and House Martin Delichon urbicum towards a flying dummy

We tested for airborne epimeletic (care-giving) behaviour in Common Swift Apus apus towards young swifts during their first flight. Tests were performed where colonies of Common Swift and Western House Martin Delichon urbicum co-occur. Three variants of a flying dummy were used; two with pointed wings of which one entirely black (1) and one with partly white body (2). The third was black with broad wings (3). Reactions were documented on film. Swifts and martins had opposite reactions to dummies 1 and 2. As we anticipated, martins seemed supportive in a test with dummy 2 and seemed to “guide” the dummy epimeletically. However, a swift approached dummy 2 in a support-like attempt, but deviated after a close look. In a test with dummy 3, swifts acted highly hostilely. We discuss reasons for these outcomes and the importance of dummy appearance. We illustrate the flight paths of the dummy, swifts and martins with trajectories, and the behaviour of the Western House Martin is shown in stepwise larger magnification stills of a video.

Tracking system performance for the proposed SHADOWS experiment at CERN

The proposed SHADOWS experiment, Search for Hidden And Dark Objects With the SPS, is a proton beam-dump experiment at the CERN SPS. Positioned off-axis to suppress background, SHADOWS can profit from the high intensity ECN3 proton beam line, to explore the existence of a wide range of feebly-interacting particles (FIPs). The detector, with dimensions of 2.5 × 2.5 m2 and a length of 34 m, is designed for optimal tracking and timing performance, facilitating the identification and reconstruction of various visible final states of FIP decays. Despite the excellent outcome of the CERN SPS Committee review, the CERN Research Board decided to stop the project in March 2024. In this article we present the tracking system performance study based on simulation as presented in the Proposal. We show that using straw drift-tubes of 1 cm diameter, we can achieve a few mm vertex resolution and 1% mass resolution.

The Commodification of the Womb: A Historical Attack on Black Women’s Reproductive Freedom

The commodification of the Black body is a process deeply rooted in slavery that has transcended a century’s worth of political and social change since abolition. In a literal sense, within the context of slavery, the Black body was commodified as both a force of labour and a resource for reproduction to feed the growth of America’s slave economy. In the present day, the commodification of the Black body has taken on a political and metaphorical meaning; Black women’s bodily autonomy and reproductive freedom are commonly used as a form of political currency for anti-abortion lobbyists throughout the United States. This paper covers the history of the commodification of Black women’s bodies while also displaying the ways in which Black women’s reproductive and bodily autonomy are targeted today. Drawing on theories of the fragmented commodity, the right to privacy, and reproductive freedom, this paper displays modern issues that are part of a historical continuity of targeting black women and their right to freedom.

Prediction of automotive body-in-white distortion in paint baking process

Thermal-induced distortion prediction of thin shell structures is a challenging task. It often involves highly nonlinear buckling behaviour, where the critical buckling temperature and post-buckling deformations are very sensitive not only to structural stiffness and boundary conditions but also minute geometric imperfections (a.k.a., “surface quality”) of the incoming parts. In the present work, novel Computer Aided Engineering (CAE) methods were developed to predict the thermal-induced distortion of automotive Body-in-White (BIW) panels during paint shop oven-baking processes. The CAE methodology consist of a set of three Finite Element Analysis (FEA) procedures, i.e., thermal-buckling mode analysis, thermo-structural analysis, and imperfection analysis. Two vehicle level case studies showed that simulations successfully predicted the thermal-induced distortion for panels such as the Body Side Outer (BSO) header. It was concluded that the distortion depends primarily on the temperature difference between the BSO and the rest of the BIW during the oven-baking process, rather than the temperatures themselves. Body panel forming quality (e.g., residual stresses and thickness thinning) and assembly dimensional quality were also found to impact the distortions.

An analytical I-V model of SiC double-gate junctionless MOSFETs

Silicon carbide(SiC) double gate junctionless metal oxide semiconductor field-effect transistors(DG JL MOSFETs) have attracted significant attention due to their ideal high temperature characteristics and radiation resistance. Therefore, it is meaningful to exploit an I-V model for SiC DG JL MOSFETs. In this article, we make a linear approximation to describe the relationship between the surface mobile charge density and the surface electron concentration of the device. Based on this approximation and using the one-dimensional Poisson’s equation, we solve for the potential distribution of a SiC DG JL MOSFET in the subthreshold region. From this solution, we derived a functional relationship between the surface mobile charge density in the channel and the channel quasi-Fermi potential. Then we successfully developed a unified I-V model for the SiC DG JL MOSFETs. Based on the drain to source current calculation formula, the calculation expressions for the device’s transconductance and output conductance are derived. By comparing our model with the results from the two-dimensional numerical simulation software Silvaco Atlas, our model’s calculations closely match the two-dimensional numerical simulation results from the subthreshold region to the accumulation region. This model has reference significance for SiC DG JL MOSFETs in the high temperature electronic circuit application field.

Revealing the state transition of Cen X-3 at high spectral resolution with Chandra

Cen X-3 is a compact, high-mass X-ray binary (HMXRB), likely powered by Roche lobe overflow. We present a phase-resolved X-ray spectral and timing analysis of a target of opportunity Chandra observation made during a low-flux to high-flux transition. The high-resolution spectra allow us to delve into the events that occurred during this episode. The spectrum is described by a single black body absorbed by a local column density of the order of 1023 − 24 cm−2, which is one to two orders of magnitude higher than found for previous analyses of data taken at similar orbital phases. Such a large column produces a Compton shoulder in the Fe Kα line. The transition appears to be caused by the onset of efficient cooling, which cools the plasma by 10 million degrees in just 10 ks, allowing matter to enter the magnetosphere. This happens after a major disturbance, probably the arrival of a train of wind clumps with individual masses in the range 1019 − 20 g. This train moves ballistically in an eccentric orbit around the NS, producing a distinctive Doppler modulation in the Fe XXV line.

International sports federations as de facto lawmakers: Queer-feminist explorations of the gendered power of sports law

Abstract This article analyses the law-making power of international sports federations, with a specific focus on their authority of shaping global norms on gender. It explores a variety of international sporting rules from feminist and queer perspectives. These include the ban of rainbow armbands at the 2022 FIFA (Men’s) World Cup, rules on the participation of transgender persons in rugby, gendered and racialized uniform regulations in sports, and the Semenya case concerning the sports participation of women with variations in sex characteristics The analysis asserts that despite being non-state actors, international sports federations are de facto international lawmakers that disseminate hegemonic gender norms reflecting cis-hetero-sexism and white body norms. However, analysing the Semenya case and the decision of the Chamber of the European Court of Human Rights in the case shows that the law-making power of international sports federations in shaping gender norms is not absolute but embedded in a transnational network of norms. The article concludes that subjecting international sports federations to a feminist, queer, and anti-racist legal analysis assists in understanding how hegemonic norms on gender circulate transnationally and enhances knowledge on how international law works in practice.

MIRI MRS Observations of Beta Pictoris. II. The Spectroscopic Case for a Recent Giant Collision

Modeling observations of the archetypal debris disk around β Pic, obtained in 2023 January with the MIRI Medium Resolution Spectrograph on board JWST, reveals significant differences compared with that obtained with the Infrared Spectrograph on board Spitzer. The bright 5–15 μm continuum excess modeled using a ∼600 K black body has disappeared. The previously prominent 18 and 23 μm crystalline forsterite emission features, arising from cold dust (∼100 K) in the Rayleigh limit, have disappeared and been replaced by very weak features arising from the hotter 500 K dust population. Finally, the shape of the 10 μm silicate feature has changed, consistent with a shift in the temperature of the warm dust population from ∼300 to ∼500 K and an increase in the crystalline fraction of the warm, silicate dust. Stellar radiation pressure may have blown both the hot and the cold crystalline dust particles observed in the Spitzer spectra out of the planetary system during the intervening 20 yr between the Spitzer and JWST observations. These results indicate that the β Pic system has a dynamic circumstellar environment, and that periods of enhanced collisions can create large clouds of dust that sweep through the planetary system.

Analysis of a thermal correction method for infrared spectroscopy : preparation for the future observations of the Martian moons Phobos and Deimos with the MIRS instrument

Abstract The MIRS infrared spectrometer is part of the scientific payload of JAXA’s Martian Moon eXploration (MMX) mission. From the reflected sunlight by the planetary surfaces, MIRS will provide information on the Mars atmosphere and the mineralogy and chemistry of its moons. Spectra carried out by the instrument (0.9-3.6 µm) include the thermal emission from the surface, which needs to be modeled and removed to extract the compositional information. In this study, to find an efficient and rapid way to thermally correct infrared data, we developed a simple thermal emission correction based on black body fits, and quantify its relative error. To test the method, we generated synthetic spectra of Phobos by using a thermophysical model. We found that the method can produce reflectance spectra with only a few percent errors, although some under-correction of the thermal contribution is observed. Compositional information may still be retrieved through the position of absorption bands, despite the thermal emission correction can leave some uncertainties in its strength. We conclude that the method could be used for a first and quick analysis for interpretation of the MIRS data. We also applied our thermal correction methodology to real CRISM observations of Phobos. The method looks reliable with a satisfactory removal of the thermal contribution, confirms the presence of an absorption band centered around 2.8 µm, and reveals an apparent absorption at 3.2 µm. However, we are not able to confirm the reality of the 3.2 µm band at this stage, because of the presence of an artifact in CRISM data.

An illumination-guided dual attention vision transformer for low-light image enhancement

Existing Retinex-based low-light image enhancement methods often overlook corruptions hidden in darkness or pattern collapse caused by the lit-up process. Recent deep learning approaches suggest the use of U-shaped networks with Vision in Transformer (VIT) to address these issues. However, most VIT-based methods focus on channel modeling to reduce expensive computational costs, but in which the restored images suffer from spatial illumination inconsistencies, artifacts, and blurriness. To end for this, we propose a novel one-stage Retinex-based Illumination-Guided Dual transformer model (IGDFormer) to lit up low-light images. The model consists of an estimator and a restorer. The estimator generates a light-up feature map and a lit-up image through pure Convolutional Neural Networks (CNNs). The restorer denoises the lit-up image with a U-shaped network equipped with an Illumination-Guided Dual Attention Block (IGDAB). Specifically, IGDAB consists of cascaded channel attention and window attention that achieves cross-channel/spatial modeling. Channel attention alleviates inductive bias through the CNN-Transformer collaborative layer, and window attention introduces spatial domains knowledge by partitioning and shifting. In addition, the light-up features act as values guide the interaction modeling of non-local illumination intensities in both the channel and spatial domains. Extensive experiments were conducted on 5 low-light image enhancement benchmarks and 1 dark object detection benchmark, which demonstrate that the efficacy of our IGDFormer and its superiority in restoring spatial details compared to other state-of-the-art methods. The code is available at https://github.com/YanJieWen/IGDFormer-light-up-dark.