Measurement of neutron spectra in liquid hydrogen Quarterly progress report, period ending Dec. 17, 1965

Neutron spectra measurement in liquid hydrogen, water cooled fast neutron source, thermal neutron measurements, and liquid hydrogen facility checkout using nitroge

Spatial distribution of the neutron flux on the surface of a graphite-lined cavity

Statement of responsibility on title-page reads: J.T. Madell, T.J. Thompson, A.E. Profio, and I. Kaplan"April 1, 1962.""NYO-9657."Includes bibliographical references (leaves 315-316)U.S. Atomic Energy Commission contract AT(30-1)234

Studies of reactivity and related parameters in slightly enriched uranium, heavy water lattices

Statement of responsibility as it appears on title page reads: B. K. Malaviya, I. Kaplan, D. D. Lanning, A. E. Profio , T. J. Thompson"May 25, 1964."MIT-2344-1Includes bibliographical referencesU.S. Atomic Energy Commission contract AT(30-1)234

Measurements of the spatial and energy distribution of thermal neutrons in uranium, heavy water lattices

"August 20, 1962."Statement of responsibility on title-page reads: P. S. Brown, T. J. Thompson, I. Kaplan, A. E. ProfioAlso issued by the first author as a Ph. D. thesis, Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 1962"NYO-10205."Includes bibliographical references (pages 185-210)Intracell activity distributions were measured in three natural uranium, heavy water lattices of 1. 010 inch diameter, aluminum clad rods on triangular spacings of 4. 5 inches, 5. 0 inches, and 5. 75 inches, respectively, and in a uranium, heavy water lattice of 0. 25 inch diameter, 1. 03% U 2235, aluminum-clad rods on a triangular spacing of 1. 25 inches. The distributions were measured with bare and cadmium-covered foils of gold, lutetium, and europium. The gold was used as a 1/v absorber to measure the thermal neutron density distribution. Because the activation cross sections of lutetium and europium depart considerably from 1/v behavior, their activation depends strongly on the thermal neutron energy spectrum. Hence, they were used to make integral measurements of the change in the neutron energy spectrum with position in the lattice cell. A method was developed for treating the partial absorption, by cadmium covers, of neutrons at the 0.46 ev europium resonance, and it was found possible to correct the europium activations to energy cutoffs just above and just below the resonance. The measured activity distributions were compared with those computed with the THERMOS code. In the natural uranium lattices, THERMOS gave excellent agreement with the measured gold activity distributions and very good agreement with the lutetium and europium distributions, indicating that THERMOS gives a very good estimate of the spatial and energy distribution of thermal neutrons in these lattices. In the enriched lattice, THERMOS gave a large overestimate of the activity dip in the fuel for all three detectors. The discrepancy was attributed to a breakdown in the Wigner-Seitz cylindrical cell approximation at small cell radii.However, the measured ratios of lutetium and europium activity to gold activity were in good agreement with the THERMOS values, indicating that THERMOS still gave a good estimate of the degree of spectral hardening. Neutron temperature calculations were made from the data by using Westcott effective cross sections. The temperature changes so calculated agreed well with those predicted by THERMOS. Disadvantage factors calculated by the Amouyal-Benoist-Horowitz (ABH) method were in excellent agreement with the measured values in the natural uranium lattices. The agreement was not as good in the enriched lattice because of an expected breakdown in the ABH method at small cell radii. Values of the thermal utilization obtained from experiment, from THERMOS, and with the ABH method were in excellent agreement for all the lattices studied.Radial and axial buckling measurements made with lutetium were in excellent agreement with similar measurements made with gold, indicating that the thermal neutron spectrum was uniform throughout the lattice tank. Measurements of intracell gold activity distributions made in off-center cells differed only slightly from those made in the central cell of the lattice, indicating that the radial flux distribution was almost completely separable into a macroscopic Jo and a microscopic cell distribution.U. S. Atomic Energy Commission contract AT(30-1)234

BESS energy management strategies for multiple ancillary services provision

LAUREA MAGISTRALEL’obiettivo di questo lavoro è verificare l’abilità dei sistemi d’accumulo a batteria (BESS) nel fornire servizi ancillari alle rete elettrica. In particolare, si analizzano due servizi: fornitura di riserva di controllo primaria (PCR) e secondaria (SCR). Inizialmente, si analizza esclusivamente la fornitura di PCR considerando sia il modello di mercato italiano che quello tedesco. Si confrontano varie strategie di controllo dello stato di carica (SoC) e si ottimizza la migliore. In seguito, si considera la fornitura di molteplici servizi: PCR e SCR asimmetrica. Per la PCR, si considerano i modelli di mercato italiano e tedesco, mentre la remunerazione della SCR si ispira allo schema italiano. L’allocazione di bande asimmetriche di SCR agisce come strategia di controllo del SoC. Nel caso di multi-servizio, è fondamentale prevedere lo stato di carica al termine della successiva sessione di mercato per allocare le bande di SCR in maniera ottimale: si implementano vari metodi di previsione e si valutano le loro prestazioni nella fornitura di multi-servizio. I primi tre capitoli forniscono una revisione letteraria su: (i) BESS, in particolar modo sulla tecnologia a ioni di litio adottata in questo studio; (ii) mercato dei servizi ancillari, con particolare attenzione al modello italiano e tedesco; (iii) analisi predittiva, utile all’implementazione del multi-servizio. Nel Capitolo 4, si presentano la metodologia e i modelli del BESS, del controllore PCR e del controllore SCR. Tali modelli sono sviluppati in ambiente MATLAB®-SimulinkTM. Gli ultimi due capitoli mostrano i risultati delle simulazioni. La valutazione delle prestazioni della fornitura di singolo o molteplici servizi si basa principalmente su: (i) perdita di regolazione (LoR), come principale indice tecnico; esso rappresenta la percentuale di potenza non fornita rispetto a quella richiesta; (ii) valore attuale netto (NPV) e indice di profittabilità (PI), come indici di valutazione delle prestazioni economiche. I risultati principali mostrano che: (i) nel caso di singolo servizio, tutta le strategie di gestione del SoC migliorano sia le prestazioni tecniche che economiche e il ripristino del SoC senza interruzione del servizio è la strategia migliore; (ii) nel caso di multi-servizio, l’allocazione di bande asimmetriche di SCR tramite l’utilizzo di metodi di previsione funge da strategia di ripristino del SoC, determinando maggiori flussi energetici, diminuendo la LoR e generando un ritorno economico positivo.The scope of this work is to verify the ability of a Battery Energy Storage System (BESS) in providing Ancillary Services to the electrical grid. In particular, two services are investigated: Primary Control Reserve (PCR) and Secondary Control Reserve (SCR) provision. Firstly, only PCR provision is analysed considering both the Italian and German market models. Various State of Charge (SoC) restoration strategies are compared and the best one is optimized by varying its main parameters. Afterwards, multi-service provision is considered: PCR and asymmetric SCR. Either the Italian or the German market models are considered for PCR, while the SCR remuneration mechanism is inspired on the Italian scheme. The allocation of asymmetric SCR bands acts as a SoC control strategy. In case of multi-service, it is fundamental to forecast the SoC at the end of the following market session in order to optimally allocate SCR bands: different forecasting techniques are implemented and their performances on multi-service provision are evaluated. The first three chapters provide a literature review of: (i) BESS, with particular focus on the Li-ion technology adopted in this work; (ii) Ancillary Services Market, with particular attention to the Italian and German paradigms; (iii) predictive analytics, useful for multi-service implementation. In Chapter 4, the methodology is explained and the models of the BESS, PCR controller and SCR controller are presented. All the models are developed in a MATLAB®-SimulinkTM environment. The last two chapters show the results of the simulations. Performance evaluation of both single and multi-service provision is mainly based on: (i) Loss of Regulation (LoR), as main indicator of technical performance; it is the percentage of power not provided with respect to the required quantity; (ii) Net Present Value (NPV) and Profitability Index (PI), as economic performance indices. The main outcomes show that: (i) in case of single service provision, all the SoC management techniques improve both technical and economic performances and SoC restoration without service interruption is the best strategy; (ii) in case of multi-service provision, asymmetric SCR band allocation based on forecasting tools works as a passive SoC restoration strategy, leading to enhanced energy fluxes, low values of LoR and positive economic return

In vivo quantification of photosensitizer fluorescence in the skin-fold observation chamber using dual-wavelength excitation and NIR imaging

A major challenge in biomedical optics is the accurate quantification of in vivo fluorescence images. Fluorescence imaging is often used to determine the pharmacokinetics of photosensitizers used for photodynamic therapy. Often, however, this type of imaging does not take into account differences in and changes to tissue volume and optical properties of the tissue under interrogation. To address this problem, a ratiometric quantification method was developed and applied to monitor photosensitizer meso-tetra (hydroxyphenyl) chlorin (mTHPC) pharmacokinetics in the rat skin-fold observation chamber. The method employs a combination of dual-wavelength excitation and dualwavelength detection. Excitation and detection wavelengths were selected in the NIR region. One excitation wavelength was chosen to be at the Q band of mTHPC, whereas the second excitation wavelength was close to its absorption minimum. Two fluorescence emission bands were used; one at the secondary fluorescence maximum of mTHPC centered on 720 nm, and one in a region of tissue autofluorescence. The first excitation wavelength was used to excite the mTHPC and autofluorescence and the second to excite only autofluorescence, so that this could be subtracted. Subsequently, the autofluorescence-corrected mTHPC image was divided by the autofluorescence signal to correct for variations in tissue optical properties. This correction algorithm in principle results in a linear relation between the corrected fluorescence and photosensitizer concentration. The limitations of the presented method and comparison with previously published and validated techniques are discussed

Integrated Approaches to Combatting Childhood Obesity

Background: The global prevalence of childhood obesity has grown sharply in recent decades. Obesity is considered a public health problem which directly affects the health status of children in numerous ways. To combat this trend, integrated approaches are necessary to prevent childhood obesity. Strategies require a comprehensive perspective at individual and parental level alongside the adoption of measures to engage the community and environment. Summary: Prevention is addressed as crucial in limiting the pediatric obesity epidemic in the long term. Breastfeeding and appropriate complementary feeding are recognized as early dietary factors that affect the future risk of obesity development during the first 2 years of life. During childhood and adolescence, dietary patterns, eating habits, portion size, eating frequencies, and family meals are important dietary factors to target for preventive strategies, as well as parenting style which is influenced by parents' education. Physical activity promotion and the reduction of sedentary behavior are also recommended. The adherence of children and families to obesity prevention programs is highly dependent on socioeconomic factors. Moreover, setting food quality standards and public policies to promote healthy lifestyle habits is strongly advocated. The implementation of cost-effective preventive strategies is of high priority and requires an integrated approach by healthcare services. All stakeholders involved should take an active role in supporting and empowering children and families in order to cope with this multifactorial and complex disease

IBM 7094 program for calculation of fast neutron kinetics by Monte Carlo. Progress report, October, 1963

Progress report; October, 196

Measurement of neutron spectra in liquid hydrogen Final report

Differential energy flux neutron spectra in liquid hydrogen obtained by time-of-flight technique

IBM 7094 program for calculation of fast neutron kinetics by Monte Carlo. Addendum no. 1, May 1964

Addendum no. 1; May 196