Detection of neutrons is becoming of the utmost importance, especially in the studies of radioactive waste and in homeland security applications. The crisis of
3
He availability has required the ...development of innovative techniques. One solution is to develop light gas detectors for neutron counting to be used as portals for ports and airports. The neutron is converted on the Boron-coated cathode, releasing a charged particle, whose passage can be identified by the gas detector. While several technologies have been deployed in the past, the project μRANIA-V (μRwell Advanced Neutron Identification Apparatus) aims to detect thermal neutrons by means of the μRwell technology, an innovative gas detector. The goal is to produce tiles to operate as portals in homeland security or for radioactive waste management. The technological transfer towards the industry has started, thus the production can be cost-effective also owing to a construction process relatively easier compared to similar apparatus. By reading directly the signals from the amplification stage, the neutrons can be counted with simplified electronics further reducing the total cost. In this paper, the project will be described, with details on the μRwell technology and on the neutron counting, on the test beam performed, and on the future plans.
•Hydrogen based systems equipped with a storage can improve renewable integration.•Micro genetic algorithm results adequate to size hydrogen systems.•Decentralized control allows managing hydrogen ...systems in secondary substations.•The studied distribution system achieves 38.7% of self-consumed renewable energy.•Reverse power flows are reduced of 14.7% by means of 10 hydrogen systems.
The increasing penetration of distributed generation at LV and MV level is a hard challenge for Distribution System Operators (DSOs). Hydrogen technologies have recorded a great interest in the last decades as promising drivers for the energy transition. This paper proposes the installation of Hydrogen Systems (HSs), consisting of Fuel Cells, Electrolysers and hydrogen storage, in order to increase energy performances of the Distribution Network (DN) and to better integrate distributed generation. HSs location and sizing problem is solved considering the necessity for DSOs to ensure the secure and stable DN operation. HSs are not influenced by other end uses related to other energy sectors and are characterized by a fully decentralized management system, applicable in Secondary Substations (SSs). The evaluation is based on the concept of Energy Districts (EDs), defined as a group of SSs that present a single point of connection with the rest of the radially operated DN. The DN of the city of Terni is the real case study: available data measured at SSs for every quarter hour of year 2019 are used. 10 HSs are installed by the algorithm, reaching a high rate of renewable energy self-consumed and a relevant decrease of Reverse Power Flows.
The upgrade of the KLOE detector at DAFNE, the Φ-factory at the Laboratori Nazionali di Frascati, foresees the insertion of an Inner Tracker around the interaction region, composed of four layers ...with diameters from 26cm to 41cm and an active length of 70cm. Each layer is realized as a cylindrical triple-GEM detector, a solution that allows to keep the total material of the Inner Tracker below 2% of a radiation length, which is of utmost importance to limit the multiple scattering of low-momentum tracks and to minimize dead spaces, thus maximizing the detector's active area. The peculiar read-out pattern with X and V strips provides a spatial resolution of about 200μm and 400μm for azimuthal and longitudinal coordinates, respectively.
After 2 years, the construction of the Inner Tracker has been completed and the detector is ready to be inserted in the KLOE apparatus for a next data-taking run. The details of the manufacturing procedure as well as the results of validation tests are reported.
•Cross-country faults are not rare with ungrounded/high-impedance grounded neutral.•Cross-country faults can involve large currents liable to damage MV cable sheaths.•Use of current-limiting reactors ...in series with MV cable sheaths is investigated.•Reactor sizing formulas based on maximum sheath current or voltage are proposed.•Simulation of an existing 20 kV grid confirms the effectiveness of the methodology.
MV distribution networks with ungrounded or grounded neutral by compensating impedance are exposed to Cross-Country-Faults (CCFs). If CCFs occur in cable lines, fault current value can reach that of line-to-line fault current. This is because the large part of the fault current flows through cable screens and only a small amount through grounding systems of secondary and primary substations. Cable screens in the joints can reach very high local temperatures where screen and copper stocking connecting the sectioned screens are not pressed enough each other. In these small areas high electric contact resistances cause large joule losses, potentially leading to insulation burning. Successive temporary/switching over voltages can cause dielectric failure, i.e. faults to ground. A way to prevent the screen insulation thermal damage could be a drastic reduction of CCF currents, especially when they occur in different cable feeders of the MV network. The paper illustrates a countermeasure able to reduce CCF currents: the use of current limiting reactors (CLRs) connecting the cable screens to the earth electrode of the primary substation. The influence of the CLRs on the equivalent earth impedances of primary and secondary substations is investigated. The methodology is applied to an existing MV distribution network.
The paper deals with the temporary overvoltages that build up in radial MV distribution networks following the inception of a 1-phase-to-ground fault. It will be demonstrated that, for extended ...cable/overhead MV distribution networks with ungrounded neutral, in case of low resistance faults at critical locations along overhead lines, the neutral voltage can reach very large values, significantly higher than 1
p.u. (up to 2.5
p.u.). The attendant temporary overvoltages on healthy phases can be very large, much higher than √3
p.u. (up to 3.5
p.u.). Fault currents are also affected, reaching twice the value calculated with simplified methods, i.e. neglecting series impedances. Quick yet accurate analytical formulas for the prediction of maximum overvoltages, fault currents and critical fault distances are presented, together with their validation by detailed ATP-EMTP simulations. The results of a study on an existing Italian 15
kV–50
Hz extended mixed cable/overhead distribution network are finally presented and discussed.
Gentrification in cities in the United States is a hot topic, but this book contributes something new to the ongoing discussion by offering a rich case study of seasonal gentrification and its ...effects on long time residents. Asbury Park, New Jersey, an iconic beachfront city, was a dynamic resort community in the late 19th and early 20th century. As the century wore on Asbury Park became an illustration of some of the macro social and economic structural changes occurring in cities across the United States with its own beachfront twist. Yet in 2019 Asbury Park’s narrative has shifted again—named among the coolest small towns in America the city has multimillion-dollar beachfront condos attracting the attention of Hollywood stars and national media attention as a travel destination. Summer days in Asbury once again mean tourists strolling the boardwalk and dining by the Atlantic Ocean. But just across the railroad tracks from the seasonal crowds, many of Asbury’s long-time residents live below poverty and struggle for their share of this prosperity throughout all four seasons of the year.
Molly Vollman Makris and Mary Gatta engage in a rich ethnographic investigation of Asbury Park to better understand the connection between jobs and seasonal gentrification and the experiences of long time residents in this beach-community city. They demonstrate how the racial inequality in the founding of Asbury Park is reverberating a century later. This book tells an important and nuanced tale of gentrification using an intersectional lens to examine the history of race relations, the too often overlooked history of the post-industrial city, the role of the LGBTQ population, barriers to employment and access to amenities, and the role of developers as the city rapidly changes. Makris and Gatta draw on in-depth interviews, focus groups, ethnographic observation as well as data analysis to tell the reader a story of life on the West Side of Asbury Park as the East Side prospers and to point to a potential path forward.
•A nonlinear thermal circuit model of underground MV power cables has been implemented.•Cold-shrinkable joints have also been modeled.•The model is validated by experimental tests in steady state and ...during transients.•Simulations show that the joint is always the coldest part of the cable.
The analysis of the thermal stress of underground MV power cable joints under different environmental conditions, both in normal operation and during faults, is crucial to assess any correlation between the occurrence of overheatings and the anomalous increase of failures (two to three times compared to previous years) which have been observed in the Italian distribution network during summer 2015 (the hottest year ever since 1880). In order to perform this analysis, we have developed a nonlinear circuit model that is able to estimate, both in stationary conditions and in transient ones, temperature profiles inside MV joints, referring to different environmental conditions and with current flowing both in the core conductor and in the metallic shield. The model has been implemented in the Simulink environment and then it has been validated with a set of experimental tests, specifically set up in order to check its performance in steady state and during transients. The numerical results were always in good agreement with the measurements. Subsequently, the circuit model has been employed to perform a predictive analysis of the joint internal temperatures, which may be achieved in operation and during faults by varying the ambient temperature. In all cases, the temperature limits tolerated by insulations have never been exceeded.
The aim of this study was to analyse the pharmacokinetic behaviour of amikacin in patients with haematological malignancies using a mixed-effect model and sparse data collected during routine ...clinical care. The patient population comprised 207 haematology patients divided into two groups: one for computing the population model (n = 134) and the other for validation (n = 73). A one-compartment model was used and the following covariates were tested for their influence on clearance and volume of distribution: age, gender, weight, parenteral nutrition, creatinine clearance, stage of antineoplastic treatment (induction, consolidation, intensification), number of weeks postchemotherapy, clinical diagnosis, Eastern Cooperative Oncology Group score, neutropenia, hypoalbuminaemia, concomitant medication (vancomycin and/or amphotericin B), overhydration, and autologous or allogenic bone marrow transplant. The nonlinear mixed-effect model (NONMEM) was used to assess the population pharmacokinetic model of amikacin in these patients. Apart from bodyweight and renal function, acute myeloblastic leukaemia and hypoalbuminaemia proved to be the most important covariates explaining the interindividual variability in amikacin pharmacokinetics in patients with haematological malignancies. The predictive performance of this population model for amikacin serum concentrations seems suitable for clinical purposes.
Aims: This study was planned to investigate the diagnostic utility of osmophobia as criterion for migraine without aura (MO) as proposed in the Appendix (A1.1) of the International Classification of ...Headache Disorders (ICHD-II, 2004).
Methods: We analysed 1020 patients presenting at 10 Italian juvenile headache centres, 622 affected by migraine (M) and 328 by tension-type headache (TTH); 70 were affected by headache not elsewhere classified (NEC) in ICHD-II. By using a semi-structured questionnaire, the prevalence of osmophobia was 26.9%, significantly higher in M than TTH patients (34.6% vs 14.3%).
Results: Osmophobia was correlated with: (i) family history of M and osmophobia; and (ii) other accompanying symptoms of M. By applying these ‘new’ criteria, we found an agreement with the current criteria for the diagnosis of migraine without aura (MO) in 96.2% of cases; 54.3% of previously unclassifiable patients received a ‘new’ diagnosis.
Conclusions: In conclusion, this study demonstrates that this new approach, proposed in the Appendix (A1.1), appears easy to apply and should improve the diagnostic standard of ICHD-II in young patients too.
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