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The publication presents and reviews the results of a physical modelling study of the Cross Wedge Rolling process of ball-studs. The ball-studs was formed in a double system from C45 steel at 1050°C, while the physical modelling process was performed on a scale of 1:2.5 using Primo plasticine as the model material, which was formed at 5°C. For the real tests, steel tools were used, while for the model tests the tools were made of ABS plastic. The experimental tests were followed by measurements of the individual stud steps. The geometrical analysis of the specimens showed that the model material allowed the shape of the forging obtained in the rolling process to be accurately modelled. Based on the physical modelling studies of the Cross Wedge Rolling process of ball-studs, it was concluded that the ball-studs rolling process can be modelled using PRI MO plasticine. Based on the analysis of the physical modelling results obtained, it was concluded that physical modelling allows the Cross Wedge Rolling process to be modelled with a high convergence of the results obtained in real and physical tests. [ABSTRACT FROM AUTHOR]

The control rod withdrawal (CRW) transient is one of the most important safety issues for the early design phase of sodium fast reactors (SFR). CRW transients can cause core melting, which can lead to severe accidents. To ensure the integrity of the core, it is crucial to study CRW transients in detail since early design phase of the reactor. Two approaches are used in numerical modeling of transients at CEA. Reference codes (APOLLO3 (Schneider et al., 2016), GERMINAL (Lainet et al., 2019) for example) are used to perform detailed and precise calculations, recently these tools are being coupled to form multiphysics platforms such as described in Pascal et al. (2021); Li et al. (2023). Despite being robust and validated, this type of simulation is not adapted to design phases due to the need in computing resources it requires. The second type of approach, selected in this paper, is to use simplified, parametric tools with a limited validity range. We present here a new numerical tool called MORPHEE, which is capable of simulating CRW transients. MORPHEE is a multiphysics and multiscale tool that includes neutronics, thermal-hydraulics, and fuel behavior. The tool has been developed to provide a comprehensive understanding of the CRW transient and to assess the safety of SFR. It is based on MACARENa (Droin et al. 2020) and OCARINa (Herbreteau et al. 2018) tools. They have been validated for simulation of thermal-hydraulics and fuel pin behavior, respectively. MORPHEE uses finite-differences methods to solve thermal-hydraulics equations, neutron kinetics equations and mechanical equations. A machine learning model (Jeannin et al., 2022) is also used to predict fuel cladding heat transfer through the gap. The simulations have demonstrated the importance of considering the multiphysics and multiscale aspects of the CRW transient to predict the behavior of the reactor during an accident. In conclusion, MORPHEE is a numerical tool that can simulate the CRW transient in SFR. It can be used to study the safety of SFR during the early design phase and to optimize the design to ensure the safety of the reactor. • Multiphysics methodology for Sodium Fast Reactors transients simulation. • Control Rod Withdrawal (CRW) phenomenological-based modeling with MORPHEE tool. • CRW modeling tool to guide design of SFR during the conception phase regarding safety. • Fuel cladding heat exchange coefficient and impact on transients over power. • Neutronics simplified simulation of flux shape deformation. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective: To assess the accuracy of the target trajectories and complications risk rate of computed tomography (CT) guided stereotactic surgery in the diagnosis of deep seated, small and eloquent area brain lesion. Methods: This three years study from March 2006 to April 2009 was conducted at Department of Neurosurgery, Jinnah Postgraduate Medical Centre Karachi. The study includes 44 patients with clinical and radiologicaly diagnosed brain space occupied lesion (SOL). Relevant history was obtained and clinical and neurological examination was done. CT scan brain and magnetic resonance imaging (MRI) brain with contrast performed. The Cosman Roberts Well (CRW) arc based frame used for all procedures. Results: Procedure was carried on 44 patients, 15 females and 29 males with female to male ratio of 1:1.93. Biopsy was performed for deep seated lesions n=23, midline and corpus callosum tumors n=11, lobar lesion n=9 and in 1 patient biopsy taken for suprasellar cystic SOL, with reservoir placement. Astrocytic neoplasm was the commonest which include n=26 (59.09%) cases. Forty two biopsies were positive and clinically and radiologicaly correlated. Two biopsies results were not confirmed. The mortality were n=2 (4.45%). Conclusion: Stereotactic procedure is easy to perform, accurate in targeting the lesion, and spare patients from undergoing major surgical procedures. The specimen taken for biopsy is adequate for diagnosis. Target localization is more than 95% if meticulous methodology is applied. Overall, complications arising from stereotactic brain biopsy are infrequent but can be disastrous.

The National Oceanic and Atmospheric Administration (NOAA) Coral Reef Watch (CRW) program has been providing resource managers, scientific researchers, and other coral reef ecosystem stakeholders with coral bleaching heat stress products for more than 20 years. The development of the CoralTemp sea surface temperature (SST) dataset has allowed CRW to produce the Coral Bleaching Heat Stress product suite with climatologies and daily SST measurements from within the same SST dataset, significantly improving data quality. Previously, the Monthly Mean (MM) SST and Maximum Monthly Mean (MMM) SST climatologies were derived using a different dataset from the near real-time SST. Here we provide an up-to-date description of how each product within the Coral Reef Watch Coral Bleaching Heat Stress product suite version 3.1 is derived, including descriptions of the MM, MMM, SST Anomaly, Coral Bleaching HotSpot and Degree Heating Week (DHW) products.

The National Oceanic and Atmospheric Administration's Coral Reef Watch program developed and operates several global satellite products to monitor bleaching-level heat stress. While these products have a proven ability to predict the onset of most mass coral bleaching events, they occasionally miss events; inaccurately predict the severity of some mass coral bleaching events; or report false alarms. These products are based solely on temperature and yet coral bleaching is known to result from both temperature and light stress. This study presents a novel methodology (still under development), which combines temperature and light into a single measure of stress to predict the onset and severity of mass coral bleaching. We describe here the biological basis of the Light Stress Damage (LSD) algorithm under development. Then by using empirical relationships derived in separate experiments conducted in mesocosm facilities in the Mexican Caribbean we parameterize the LSD algorithm and demonstrate that it is able to describe three past bleaching events from the Great Barrier Reef (GBR). For this limited example, the LSD algorithm was able to better predict differences in the severity of the three past GBR bleaching events, quantifying the contribution of light to reduce or exacerbate the impact of heat stress. The new Light Stress Damage algorithm we present here is potentially a significant step forward in the evolution of satellite-based bleaching products. [ABSTRACT FROM AUTHOR]

Chemical compatibility is a key consideration throughout the chemical industry wherever two or more chemicals have the potential to mix, either inadvertently or by design. One of the most comprehensive tools available for determining chemical compatibility, the NOAA Chemical Reactivity Worksheet (CRW), has gained significant traction since the release of the third version (CRW3) in 2012. In 3 years, this free software has been downloaded >200,000 times and has become the chemical compatibility tool of choice at many organizations. As a result of an ongoing partnership between the National Oceanic and Atmospheric Administration (NOAA), The Dow Chemical Company, The Center for Chemical Process Safety (CCPS), Materials Technology Institute (MTI) and other industrial/academic/government volunteers, a fourth version of the CRW (CRW4) has been developed. The expanded capabilities of this new version include a materials of construction section, improved import/exporting/data sharing capabilities, additional reactive groups to aid in determining compatibility decisions, several user interface enhancements, along with the correction of minor issues found in the CRW3. This article will describe past development, the new features included in the CRW4, followed by a brief discussion of future development plans for the software tool. Such developments should solidify this tool's position as the gold standard within the chemical industry for determining chemical hazards. © 2016 American Institute of Chemical Engineers Process Saf Prog 36: 24-29, 2017 [ABSTRACT FROM AUTHOR]

Coral bleaching heat stress products provide real-time and rapid coral bleaching alerts for coral reefs globally. However, geographical variations in the alert accuracy of multi-source coral bleaching heat stress products exist. Taking the coral reefs in the South China Sea (SCS) as the study area, we evaluated and improved the coral bleaching alert capabilities of two coral bleaching heat stress products: Coral Reef Watch (CRW) and Coral Reef Temperature Anomaly Database (CoRTAD). Using in situ coral bleaching survey data and evaluation indicators, the optimized thresholds of degree heating weeks (DHWs) for coral bleaching alerts were determined. The results in the SCS indicated that, first, CRW was better than CoRTAD for coral bleaching event alerts. However, both products underestimated coral bleaching events using the common DHW thresholds of 4°C-weeks and 8°C-weeks. Second, the DHW optimized threshold for CRW was 3.32°C-weeks for coral bleaching event alerts and 4.52°C-weeks for severe coral bleaching event alerts. For CoRTAD products, the DHW optimized threshold was 2.36°C-weeks for coral bleaching event alerts and 4.14°C-weeks for severe coral bleaching event alerts. This study proposed a method to evaluate and optimize the alert capability of multi-source coral bleaching heat stress products, which can provide more accurate basic data for coral reef ecosystem health assessment and contribute to global coral reef ecosystem protection and restoration. • A method to evaluate and optimize the alert capability of coral bleaching heat stress products in the SCS. • Optimized DHW thresholds for coral bleaching alerts were 3.32°C-weeks for CRW and 2.36°C-weeks for CoRTAD. • Optimized DHW thresholds for coral severe bleaching alerts were 4.52°C-weeks for CRW and 4.14°C-weeks for CoRTAD. • CRW was better than CoRTAD for coral bleaching event alerts in the SCS. [ABSTRACT FROM AUTHOR]

As a result of a two-year joint effort between the National Oceanic and Atmospheric Administration (NOAA) and The Dow Chemical Company, an enhanced version (3.0) of the NOAA Chemical Reactivity Worksheet now is available. In addition to addressing previously identified limitations with version 2.0 of this tool, several enhancements have been incorporated into the tool to help with the generation and presentation of chemical compatibility charts. This article covers the development and use of this new tool, highlighting the enhancements that position this tool to become the gold standard within the chemical industry for determining chemical compatibility. © 2013 American Institute of Chemical Engineers Process Saf Prog 33: 4-18, 2014 [ABSTRACT FROM AUTHOR]

Particle dispersion and deposition in turbulent pipe flows were studied numerically. The mean flow solution was calculated via a Reynolds Stress Model. Three different stochastic models were used to evaluate the effect of instantaneous fluctuations on entrained particles including the standard Discrete Random Walk (DRW) model available in Ansys-Fluent and two Continuous Random Walk (CRW) schemes that solve a normalized Langevin equation to better account for the effects of inhomogeneous turbulence on particle entrainment. Special attention is paid to the inconsistent directional vector resulting from solving the Langevin equation in non-rectangular geometries in location-specific coordinate systems. Concentration, axial distributions of deposition velocity, and deposition velocity versus particle relaxation time were compared with existing experiments and direct numerical simulation (DNS) using two different geometries. The validity of DNS data for near wall corrections were discussed. A third geometry representative of the hot section of a gas turbine was employed to study the capability of DRW and CRW on modeling spatially-developing flows. Comparisons were drawn between different stochastic models with an all-stick condition and experimental results. It was shown that the classical DRW model tends to overpredict the effect of entrance and does not yield good agreement in the deposition statistics. The CRW model shows a promising capability of modeling particle dispersion and deposition. However, the accuracy of CRW relies heavily upon the fidelity of the underlying mean flow solution and root-mean-square turbulence statistics. • Stochastic models were employed to model particle transport in turbulent flow. • Problems for implementing CRW in nonrectangular geometry were discussed. • DRW gives poor prediction in the deposition velocity versus axial position. • Without DNS corrections, CRW tends to overpredict deposition velocity. • Particle deposition in a non-axisymmetric pipe with two inlets was modeled. [ABSTRACT FROM AUTHOR]

Abstract: Turbulent flow field and particle deposition in a realistic model of human upper airway system including: nasal cavity, nasopharynx, oropharynx, larynx and trachea were analyzed numerically. The Lagrangian approach was used to find the trajectories of micron-size particles for the breathing rates of 30, 45 and 60l/min. The continuous phase flow was evaluated using a RANS (Reynolds Average Navier-Stokes) turbulence model and the effect of turbulent fluctuations on particle trajectories was modeled using a continuous random walk (CRW) stochastic model, which is based on the normalized Langevin equation. The total and regional deposition fractions of micro-particles were evaluated and the effect of turbulent fluctuations on the particle deposition rate was investigated. [Copyright &y& Elsevier]

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The National Oceanic and Atmospheric Administration (NOAA) Coral Reef Watch (CRW) program has been providing resource managers, scientific researchers, and other coral reef ecosystem stakeholders with coral bleaching heat stress products for more than 20 years. The development of the CoralTemp sea surface temperature (SST) dataset has allowed CRW to produce the Coral Bleaching Heat Stress product suite with climatologies and daily SST measurements from within the same SST dataset, significantly improving data quality. Previously, the Monthly Mean (MM) SST and Maximum Monthly Mean (MMM) SST climatologies were derived using a different dataset from the near real-time SST. Here we provide an up-to-date description of how each product within the Coral Reef Watch Coral Bleaching Heat Stress product suite version 3.1 is derived, including descriptions of the MM, MMM, SST Anomaly, Coral Bleaching HotSpot and Degree Heating Week (DHW) products. [ABSTRACT FROM AUTHOR]

Since the beginning of recorded history, humans have sought a physical means of altering disordered behavior and consciousness. This quest has spawned numerous innovations in neurosurgery and the neurosciences, from the earliest prehistoric attempts at trepanation to the electrocortical and anatomic localization of cerebral function that emerged in the 19th century. At the start of the 20th century, the overwhelming social impact of psychiatric illness intersected with the novel but imperfect understanding of frontal lobe function, establishing a decades-long venture into the modern origin of psychosurgery, the prefrontal lobotomy. The subsequent social and ethical ramifications of the widespread overuse of transorbital lobotomies drove psychosurgery to near extinction. However, as the pharmacologic treatment of psychiatric illness was established, numerous concomitant technical and neuroscientific innovations permitted the incremental development of a new paradigm of treating the disordered mind. In this article, we retrospectively examine these early origins of psychosurgery and then look to the recent past, present, and future for emerging trends in surgery of the psyche. Recent decades have seen a revolution in minimalism, noninvasive imaging, and functional manipulation of the human cerebrum that have created new opportunities and treatment modalities for disorders of the human mind and mood. Early contemporary efforts were directed at focal lesioning of abnormal pathways, but deep-brain stimulation now aims to reversibly alter and modulate those neurologic activities responsible for not only psychiatric disorders, but also to modulate and even to augment consciousness, memory, and other elements of cerebral function. As new tools become available, the social and medical impact of psychosurgery promises to revolutionize not only neurosurgery, but also humans' capability for positively impacting life and society., (Copyright © 2012 Elsevier Inc. All rights reserved.)