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Valid assessment of physical activity must be unobtrusive, practical to administer, and specific about physical activity type, frequency, duration, and intensity. Assessment methods can be categorized according to whether they provide direct or indirect (e.g., self-report) observation of physical activity, body motion, physiological response during physical activity, energy expenditure, or physiological adaptation to physical activity. (SM)

Provides information on nutritional caloric value determination. Describes the chemical components of peanuts. Explains how to construct a soda can calorimeter for determining the heat released by a burning nut. Describes how to determine calories and kilocalories. Author asserts the activity can be adopted for children of any age. (eight references) (PR)

Described are the apparatus and procedures needed for this correction technique using a microcomputer interface. Discussed are materials, apparatus construction, and experimental results. (CW)

Four applications of microcomputers in the chemical laboratory are presented. Included are "Mass Spectrometer Interface with an Apple II Computer,""Interfacing the Spectronic 20 to a Computer,""A pH-Monitoring and Control System for Teaching Laboratories," and "A Computer-Aided Optical Melting Point Device." Software, instrumentation, and uses are discussed. (CW)

Described are the design, construction, and uses of two pieces of laboratory equipment. Included are a multipurpose meter, "Calo-pH Meter," and a device for collecting water samples for determining dissolved oxygen content. (CW)

Gives a simple but fuller account of the basis for accurately calculating temperature rise in calorimetry. Points out some misconceptions regarding these calculations. Describes two basic methods, the extrapolation to zero time and the equal area method. Discusses the theoretical basis of each and their underlying assumptions. (CW)

Presents a step-by-step approach to be used in solving different forms of physics problems, starting from familiar grounds and finding well known results on the way. Uses the rate of heat flow and the resulting changes of temperature with time of a copper block as an example. (GA)

Describes a method to demonstrate induction heating by placing an ordinary mercury thermometer in a high frequency magnetic field and observing the temperature rise. Also describes an ice calorimeter for measuring the mechanical equivalent of heat. (SK)

Suggests seven take-home experiments geared toward the topic of energy that can be utilized in large, general-education physics classes that do not include laboratory sessions. An appendix provides details for the experiment to measure the heat of fusion of water. (MDH)

Suggests an apparatus to improve the measurement of the mechanical equivalent of heat. Describes the materials needed to construct the apparatus; the methodology of an experiment to measure the heat gained by lead shot falling through a distance of 100 meters; and the calculations made to register that gain. (MDH)

Background information, laboratory procedures, and a discussion of the results of an experiment designed to investigate the difference in energy gained from the aerobic and anaerobic oxidation of glucose are presented. Sample experimental and calculated data are included. (CW)

The principles and procedures for three enthalpimetric measurement experiments including a determination of the water equivalent mass of the calorimeter, the calibration of the instrument, and determination of the dissociation heat of boric acid performed with a teacher-made instrument are presented. Suggestions for further experiments are provided. (CW)

This review covers methods of sampling, analyzing, and testing coal, coke, and coal-derived solids and methods for the chemical, physical, and instrumental analyses of gaseous fuels. The review covers from October 1986, to September 1988. (MVL)

Presents an experiment in thermometric titration used in an analytic chemistry-chemical instrumentation course, consisting of two titrations, one a mixture of calcium and magnesium, the other of calcium, magnesium, and barium ions. Provides equipment and solutions list/specifications, graphs, and discussion of results. (JM)

Presents two experiments: the first one measures the heat of an exothermic reaction by the reduction of permanganate by the ferris ion; the second one measures the heat of an endothermic process, the mixing of ethanol and cyclohexane. Lists tables to aid in the use of the solution calorimeter. (MVL)

Describes two experiments designed to provide concepts on the difference between heat and temperature and also bond energy. Investigates both a neutralization experiment and a ligation experiment. Notes inexpensive chemicals are used along with simple equipment. Discusses the sharing of lab results for a single class value. (MVL)

Describes a solution calorimetry apparatus useful in measuring heats of metal ion-ligand reactions. (SK)

Briefly discusses three techniques for assessing amount of ammonia present in household cleaners. Because of disadvantages with these methods, the thermometric titration technique is suggested in which students judge the best buy based on relative cost of ammonia present in samples. Laboratory procedures, typical results, and reactions involved are considered. (JM)

Score based generative models are a new class of generative models that have been shown to accurately generate high dimensional calorimeter datasets. Recent advances in generative models have used images with 3D voxels to represent and model complex calorimeter showers. Point clouds, however, are likely a more natural representation of calorimeter showers, particularly in calorimeters with high granularity. Point clouds preserve all of the information of the original simulation, more naturally deal with sparse datasets, and can be implemented with more compact models and data files. In this work, two state-of-the-art score based models are trained on the same set of calorimeter simulation and directly compared.

Diffusion generative models are promising alternatives for fast surrogate models, producing high-fidelity physics simulations. However, the generation time often requires an expensive denoising process with hundreds of function evaluations, restricting the current applicability of these models in a realistic setting. In this work, we report updates on the CaloScore architecture, detailing the changes in the diffusion process, which produces higher quality samples, and the use of progressive distillation, resulting in a diffusion model capable of generating new samples with a single function evaluation. We demonstrate these improvements using the Calorimeter Simulation Challenge 2022 dataset.

In this study, a novel approach is demonstrated for converting calorimeter images from fast simulations to those akin to comprehensive full simulations, utilizing conditional Generative Adversarial Networks (GANs). The concept of Pix2pix is tailored for CALPAGAN, where images from fast simulations serve as the basis (condition) for generating outputs that closely resemble those from detailed simulations. The findings indicate a strong correlation between the generated images and those from full simulations, especially in terms of key observables like jet transverse momentum distribution, jet mass, jet subjettiness, and jet girth. Additionally, the paper explores the efficacy of this method and its intrinsic limitations. This research marks a significant step towards exploring more efficient simulation methodologies in high-energy particle physics. [ABSTRACT FROM AUTHOR]

This study analyzed the correlation between heat release rate and variations in the blower capacity ( Q fan ), hood skirt length ( L skirt ), and diameter ( D Hood ) of a calorimeter in large-scale fire experiments. The fire dynamics simulator (FDS) program was used to examine the time-averaged temperature ( T duct,avg ), flow rate ( m ˙ duct,avg ), and oxygen concentration changes ( Δ O 2 , avg ) inside the duct for n-heptane heat release rate input values ( Q ˙ input ) of 8000 kW, where Q fan = 1800 to 4000 m3 min−1, L skirt = 1 to 5 m, and D Hood = 4 to 11 m. The results showed that when L skirt = 2 m and D Hood = 9 m, as Q fan decreased, Δ O 2 , avg increased, whereas m ˙ duct,avg decreased. When Q fan = 1800 m3 min−1, the predicted heat release rate ( Q ˙ o,c ) derived from the oxygen consumption index was approximately 25% lower than Q ˙ input owing to overflow. When Q fan = 2600 m3 min−1 and D Hood = 9 m, the ambient air inflow increased as L skirt decreased. This reduced Δ O 2 , avg and T duct,avg , increasing m ˙ duct,avg . When L skirt = 1 m, Q ˙ o,c was over 20% lower than Q ˙ input . However, when Q fan = 2600 m3 min−1, L skirt = 2 m, and D Hood ≥ 4 m, D Hood did not significantly influence the design variables. Notably, T duct,avg emerged as a key variable determined by the total mass flow rate entering the calorimeter, which varied with Q fan and L skirt . Prediction equations for m ˙ duct,avg and Δ O 2 , avg in terms of T duct,avg were derived. A design range for the calorimeter heat release rate was proposed by analyzing L skirt . The findings of this study are significant for determining the range of Q fan , L skirt , and T duct,avg when designing calorimeters in the 5000–10,000 kW scale. [ABSTRACT FROM AUTHOR]

Cryogenic microcalorimeters are key tools for high-resolution X-ray spectroscopy due to their excellent energy resolution and quantum efficiency close to 100%. Multiple types of microcalorimeters exist, some of which have already proven outstanding performance. Nevertheless, they cannot yet compete with cutting-edge grating or crystal spectrometers. For this reason, novel microcalorimeter concepts are continuously developed. One such concept is based on the strong temperature dependence of the magnetic penetration depth of a superconductor operated close to its transition temperature. This so-called λ -SQUID provides an in-situ tunable gain and promises to reach sub-eV energy resolution. Here, we present some design considerations with respect to the optimization of such a detector that are derived by analytic means. We particularly show that for this detector concept the heat capacity of the sensor should match the heat capacity of the absorber. [ABSTRACT FROM AUTHOR]

We have modified the fabrication processes of metallic magnetic calorimeters (MMCs) to improve production yield. Key modifications include (i) the stress mitigation of the sputtered Nb film by optimizing the Argon deposition gas pressure, (ii) an optimized SiO x insulator layer fabrication by switching from a lift-off to a wet-etching method and controlling the optimizing the temperature, (iii) the joint electroplating of thick gold structures for persistent current switch leads and a thermalization layer, and (iv) a reduced sputter-deposition time of the Ag:Er sensor material by introducing a new wafer holder. These modifications contribute to increased production yield, reduced fabrication time, and enhanced overall performance. Tests on MMCs fabricated with these modifications demonstrated uniformly improved critical current of the Nb meander coils, enhanced SiO x insulation properties, strengthened persistent current switch systems, and reduced probability of Ag:Er oxidation. These modified MMC detectors also functioned well in tests for alpha spectrometry measurements, demonstrating good performance. [ABSTRACT FROM AUTHOR]

Superconducting transition-edge sensors (TESs) used in X-ray and γ -ray microcalorimeters suffer degraded performance if cooled in a magnetic field B sufficient to trap flux in the sensors. We report measurements of γ -ray TESs before and after implementing measures to reduce stray B fields from sources inside and outside the cryostat. These measurements showed a correlation between anomalous features in TES current–voltage (IV) curves and degraded energy resolution. After reducing internal sources of stray B field and improving shielding against external sources, both IV curves and energy resolution improved. Finally, we placed magnetized screws with remnant fields ∼ 10 μ T near similar γ -ray TESs in a different type of detector package and observed the same effects. [ABSTRACT FROM AUTHOR]

We present advancements in a finite element method for computing the physical properties of magnetic microcalorimeters (MMCs). Utilizing the COMSOL package, we conducted 3D simulations of a meander-shaped Nb coil with a realistic geometry. The resulting magnetic field distribution showed good agreement with a previous 2D simulation and revealed non-negligible differences at the side edge of the sensor material. Employing the simulation results, we calculated the MMC properties and compared them with previous measurements. Our calculated values closely align with the measured values for the sensor magnetization, the pulse heights from alpha detection, and the coil inductance. [ABSTRACT FROM AUTHOR]

Background: Live fuel comprises a significant portion of the fuel consumed in forest and scrub crown fires. However, its flammability remains poorly understood. Although live fuel differs from dead fuel in moisture content, chemical composition, cellular structure and physiological characteristics, its higher moisture content masks the effect of other characteristics on its flammability. Aims: The aim of the study was to delineate and assess the effects of live/dead condition, moisture content and particle size on flammability of gorse (Ulex europaeus L.). Methods: Live and dead gorse material of three size classes (0–3, 3–6, and 6–10 mm in diameter) at six moisture contents (0, 10, 25, 50, 75 and 100%) was tested in a cone calorimeter to evaluate its flammability using new sample preparation and moisture conditioning techniques. Key results: On average, live fuel ignited 21% slower, reached 11% higher peak heat release rate, and had a 12% shorter burn duration than dead fuel of the same moisture content. These differences were most pronounced in coarser material. Conclusions: For gorse, fine dead fuels increase the likelihood of ignition, fine live fuels contribute to high burning intensities, and coarser live and dead fuels prolong combustion. Implications: These findings highlight the need to account for flammability differences between live and dead fuels in fire behaviour models beyond those driven by variations in moisture content. This study compares the flammability of live and dead vegetation at a range of moisture contents and particle sizes. Live fuel took longer to ignite but burned faster and more intensely than dead fuel of the same moisture content, emphasising the importance of live fuel flammability in fire prediction models. [ABSTRACT FROM AUTHOR]

Generation of simulated detector response to collision products is crucial to data analysis in particle physics, but computationally very expensive. One subdetector, the calorimeter, dominates the computational time due to the high granularity of its cells and complexity of the interactions. Generative models can provide more rapid sample production, but currently require significant effort to optimize performance for specific detector geometries, often requiring many models to describe the varying cell sizes and arrangements, without the ability to generalize to other geometries. We develop a geometry-aware autoregressive model, which learns how the calorimeter response varies with geometry, and is capable of generating simulated responses to unseen geometries without additional training. The geometry-aware model outperforms a baseline unaware model by over 50% in several metrics such as the Wasserstein distance between the generated and the true distributions of key quantities which summarize the simulated response. A single geometry-aware model could replace the hundreds of generative models currently designed for calorimeter simulation by physicists analyzing data collected at the Large Hadron Collider. This proof-of-concept study motivates the design of a foundational model that will be a crucial tool for the study of future detectors, dramatically reducing the large upfront investment usually needed to develop generative calorimeter models.