The media now regularly feature breakthroughs on the influence of prenatal hormones on the brain and behavior, for instance the link to financial performance or risk management. Based on these ...findings and their own experiments, the authors present the Hormonal Quotient (HQ) as a scientific, holistic and reliable career management and personal development tool for professionals. Eight HQ profiles and their corresponding typical business skills and preferences are presented and enable the reader to benchmark their HQ with peers, design an ideal career plan, build a winning team in business and find the perfect work-life balance. A complimentary website allows readers to easily measure their HQ online. By the author of 'The Right Sensory Mix', Berry-AMA Book Prize Finalist 2011. Diana Derval is President and Research Director of DervalResearch, global market research firm specializing in human perception and behavior, and Chair of the Board of Directors of the Better Immune System Foundation. Inventor of the Hormonal Quotient® (HQ), member of the Society for Behavioral Neuroendocrinology, and author of the books 'Wait Marketing' and 'The Right Sensory Mix', Diana turns fascinating neuroscientific breakthroughs into powerful business frameworks to identify, understand, and predict human traits, motivations, and behavior. She has accelerated the development of Fortune 500 firms including TomTom, Michelin, Sofitel, Philips, Sara Lee, and Sephora. Diana Derval teaches Innovation and Sensory Science at ESSEC Paris-Singapore Business School, and at the MBA of the University Leonard de Vinci in Paris. Over 10,000 professionals enjoyed her inspirational lectures and workshops from Chicago to Shanghai. Johan Bremer, MSc in computer science, is the owner and technology director of Bremer Studios, a firm with expertise in 3D rendering and scientific visualization.Johan and his team have implemented in the past decade must have applications for leading organizations, including lane information on TomTom GPS navigation devices, a 3D visualization of the Anne Frank Museum tree based on a laser-scanning dataset, and neuromarketing demonstrations for DervalResearch and Philips. Combining strong mathematical skills with an ability to quickly grasp needs of demanding customers, Johan Bremer also expanded the visual program Crystal Ball, an option-risk application for traders.
A method to suppress trapping-related effects when performing IV characterizations of field effect transistors is presented. Standard IV measurements usually utilize voltage sweeps with fixed start, ...stop, and step values. At high electric fields in these sweeps, the charging of electron traps with long time constants may occur. The trapped electrons cause different memory effects such as hysteresis and the kink effect. The proposed method suppresses these effects, by reordering the bias points, so to prevent charging due to high preceding electric fields. The method provides more rudimentary IV measurements, useful for e.g. technology evaluation and modeling purposes.
Cryogenic dry cooling solutions for Superconducting RF cavities allow for synergies with modern cavity production methods based on vacuum coating and A15 SC layer deposition methods. A ...proof-of-concept cryogenic performance test stand will study relevant parameters of low-temperature cooling loops with respect to the RF performance of a 1.3 GHz prototype cavity. The paper describes cooling options concerning helium forced flow heat transfer at the capillary surface plus the conduction pathway and the consequent temperature distribution in the cavity itself. Such novel and drastically reduced helium content cooling schemes can be applied to a wide variety of SC cavity or magnet assemblies. The results of the numerical evaluation of heat transfer and pressure drop relations for two-phase and single-phase supercritical flow are cited. These data form the basis for future experimental validation campaigns in the temperature range of 4.2 K to 25 K and helium pressures of up to 2.2 MPa. Special attention is paid to possible new introduced effects of mechanical vibrations or temperature gradients along the cooling capillary when compared to a stagnant He bath cooling.
NA62 liquid krypton purity monitor Bremer, J.; Bryman, D.; Danielsson, H. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2023, Letnik:
1057
Journal Article
Recenzirano
Odprti dostop
A system for determining the purity of liquid krypton employed in the NA62 rare kaon decay experiment at CERN was developed based on the use of a time projection chamber. The attenuation of drifting ...ionization electrons from absorption of 511 keV gamma rays in liquid krypton was measured to estimate the purity. The setup was tested with krypton purified from commercial sources.
Further advancements with GaN based technologies relies on the ability to handle the heat flux, which consequently arises from the high power density. Advanced cooling techniques and thermal ...optimization of the technology are therefore prioritized research areas. Characterization techniques play a key role in the development of new cooling solutions, since these rely on accurate measurements of e.g. the temperature of the device. This thesis covers techniques to electrically characterize the lateral and vertical heat properties in GaN, and a temperature compensation technique for GaN MMICs.The first part outlines a methodology to electrically extract the thermal resistance of a GaN resistor without risking distortion from field induced electron trapping effects, which are exhibited by GaN heterostructures. The technique uses differential resistance measurements to identify a suitable resistor geometry, which minimizes trapping effects while enhancing the self-heating. Such conditions are crucial for electrical methods since these exploit the self- heating for a thermal analysis.Furthermore, a test structure and measurement method to electrically characterize the lateral heat spread was designed and evaluated. The structure is implemented with a thermal sensor, which utilizes the temperature-dependent IV characteristics of a GaN resistor, making it suitable for integration in GaN MMICs. The transient response can be obtained to extract the thermal time constants and propagation delay of the heat spread. At higher ambient temperatures, the propagation delay increases and the thermal coupling is increased.Lastly, a biasing technique to compensate for thermal degradation of the RF performance of an LNA was developed. By utilizing the gate- and drain voltage dependence of the RF performance, a constant gain against increasing temperature can e.g. be achieved.
The dynamic thermal coupling in integrated GaN power amplifiers is studied based on transient measurements on an amplifier structure with integrated temperature sensors. The results show that the ...thermal coupling from a transistor can modulate neighboring transistors with a low pass filtered response. Here, the cut-off frequency and amplitude of the modulation effect are reduced with separation while the phase shift increases. When applied to a large power amplifier, it is shown that the temperature gradient over the amplifier will vary dynamically, where five distinct time regions are identified. A numerical model is presented to validate the measurements. The results can be used to improve the accuracy of electro-thermal models of GaN power amplifiers.
An experimental setup is operational at the Central Cryogenics Laboratory of the European Organization for Nuclear Research to measure the cooling mechanisms of superfluid 4 He (He II) from prepared ...Rutherford-type superconducting cable stacks to a stagnant He II bath. For novel magnets designed for the so-called high-luminosity large hadron collider upgrade, a segment of a fully impregnated Nb 3 Sn 11T dipole magnet was measured. A dataset on the thermal behavior is presented, with homogeneous heat inputs of up to approximately 4.8 mW cm -3 corresponding to an average steady-state temperature of 3.1 K for the inner layer and 4.0 K for the outer layer when cooled via a 1.9 K He II bath. We discuss the steady state as well as transient behavior observed.
This paper presents a study of the lateral heat propagation in an aluminum gallium nitride/gallium nitride (AlGaN/GaN) heterostructure grown on a silicon carbide substrate. The study is enabled by ...the design of a temperature sensor that utilizes the temperature-dependent <inline-formula> <tex-math notation="LaTeX">I </tex-math></inline-formula>-<inline-formula> <tex-math notation="LaTeX">V </tex-math></inline-formula> characteristic of a semiconductor resistor, making it suitable for integration in GaN monolithic microwave integrated circuit technologies. Using the sensor, we are able to characterize the thermal transient response and extract lateral thermal time constants from the measurements. Time constants in the range from 25 <inline-formula> <tex-math notation="LaTeX">\mu \text{s} </tex-math></inline-formula> to 1.2 ms are identified. Furthermore, the heat propagation properties are characterized for heat source-to-sensor distances of 86-<inline-formula> <tex-math notation="LaTeX">484~\mu \text{m} </tex-math></inline-formula>, resulting in delay times from 3.5 to <inline-formula> <tex-math notation="LaTeX">111~\mu \text{s} </tex-math></inline-formula>. It is shown that both the time constants and propagation delay increase with temperature. An empirical model of the sensor current versus temperature and voltage is proposed and used to predict the junction temperature of the sensor. The study provides knowledge for heat management design and proposes an integrated temperature measurement solution for future highly integrated GaN applications.
An experimental setup is operational at the Central Cryogenics Laboratory of the European Organization for Nuclear Research to measure the cooling mechanisms of superfluid Formula OmittedHe (He II) ...from prepared Rutherford-type superconducting cable stacks to a stagnant He II bath. For novel magnets designed for the so-called high-luminosity large hadron collider upgrade, a segment of a fully impregnated NbFormula OmittedSn 11T dipole magnet was measured. A dataset on the thermal behavior is presented, with homogeneous heat inputs of up to approximately 4.8 mW Formula Omitted corresponding to an average steady-state temperature of 3.1 K for the inner layer and 4.0 K for the outer layer when cooled via a 1.9 K He II bath. We discuss the steady state as well as transient behavior observed.
This article presents an electric-based methodology for thermal characterization of semiconductor technologies. It is shown that for technologies such as gallium nitride (GaN) high electron mobility ...transistors, which exhibit several field induced electron trapping effects, the thermal characterization has to be performed under specific conditions. The electric field is limited to low levels to avoid activation of trap states. At the same time, the dissipated power needs to be high enough to change the operating temperature of the device. The method is demonstrated on a test structure implemented as a GaN resistor with large contact separation. It is used to evaluate the thermal properties of samples with different silicon carbide suppliers and buffer thickness.
