294 research outputs found
New Resilience Index for Urban Water Distribution Networks
The increased frequency of natural disasters and man-made catastrophes has caused major disruptions to critical infrastructures (CI) such as water distribution networks (WDNs). Therefore, reducing the vulnerability of the systems through physical and organizational restoration plans are the main concern for system engineers and utility managers that are responsible for the design, operation, and protection of WDNs. In this paper, a resilience index (R) of a WDN has been proposed that is the product of three indices: (1)the number of users temporarily without water, (2)the water level in the tank, and (3)the water quality. The resilience index is expected to help planners and engineers evaluate the functionality of a WDN, which includes: (1)delivering a certain demand of water with an acceptable level of pressure and quality, and (2)the restoration process following an extreme event. A small town in the south of Italy has been selected as a case study to show the applicability of this index using different disruptive scenarios and restoration plans. The numerical results show the importance of the partition of the network into districts to reduce the lack of services. It is also necessary to consider the indices separately to find trends that cannot be captured by the global index. Advantages and disadvantages of the different restoration plans are discussed. The proposed indices can be implemented in a decision support tool used by governmental agencies that want to include the restoration process, and the environmental and social aspects in their design procedure
Silicon Photomultipliers for Orbital Ultra High EnergyCosmic Ray Observation
Development of the Silicon photomultiplier Elementary Cell Add-on camera
(SiECA) has provided extensive information regarding the use of SiPMs for
future cosmic ray detection systems. We present the technical aspects of sensor
readout development utilizing Citiroc ASIC chips from Weeroc controlled by a
Xilinx FPGA to process and package events from four 64 channel Hamamatsu MPPC
S13361 arrays generating 128 frame events with an integration time of 2.5ms
(parameters are based on JEM-EUSO geometry but can be easily adjusted). With
single photon counting capability, SiECA proves SiPM are viable sensors to
replace Multi-Anode PhotoMultiplier Tubes in future devices, especially when
high luminosity exposure is possible potentially damaging MAPMT based systems.
Complementary to the technical aspects, computational and analysis methods for
sensor array characterization and in depth device flat-fielding are presented.
Provided channel by channel biasing, in comparison to uniform biasing with
MAPMTs, fine tuning of operating parameters with MPPC arrays allows for
substantial improvements in detector and signal uniformity.Comment: presented at the 36th ICRC (Madison, WI; 2019
The KATRIN Pre-Spectrometer at reduced Filter Energy
The KArlsruhe TRItium Neutrino experiment, KATRIN, will determine the mass of
the electron neutrino with a sensitivity of 0.2 eV (90% C.L.) via a measurement
of the beta-spectrum of gaseous tritium near its endpoint of E_0 =18.57 keV. An
ultra-low background of about b = 10 mHz is among the requirements to reach
this sensitivity. In the KATRIN main beam-line two spectrometers of MAC-E
filter type are used in a tandem configuration. This setup, however, produces a
Penning trap which could lead to increased background. We have performed test
measurements showing that the filter energy of the pre-spectrometer can be
reduced by several keV in order to diminish this trap. These measurements were
analyzed with the help of a complex computer simulation, modeling multiple
electron reflections both from the detector and the photoelectric electron
source used in our test setup.Comment: 22 pages, 12 figure
Community resilience assessment integrating network interdependencies
The concept of Disaster Resilience has received considerable attention in recent years and it is increasingly used as an approach for measuring response of communities to natural disasters. Recently a framework named PEOPLES has been developed by MCEER to measure performance of communities to natural disasters. The method includes seven dimensions that include both technical and socio-economic aspects. All resilience dimensions and their respective indices to measure community performances are obviously interdependent. As first step, the physical dimension has been implemented in software and indices have been proposed to measure performance of buildings and lifelines. This paper tries to focus on developing methodologies to consider interdependencies between buildings (e.g. hospitals, strategic buildings, etc) and lifelines (road networks, etc.). An approach considering network interdependencies have been developed which is based on the time series analysis of the restoration curves of the different infrastructures. The case study of 2011 Tohoku Earthquake has been presented to illustrate the implementations issue
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