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Expansion and reorganization of water distribution networks by connecting sub‐networks via single or multiple pipes are common practices in developing cities to serve newly developed areas. In that context, the existing large network is often replaced with its equivalent simplified network for the optimal design of the upcoming sub‐networks to avoid the computational burden. The reservoir‐pump model is frequently used by practicing hydraulic engineers to replace an existing one; however, such a model should be applied only when the networks are connected through a single pipe. In this study, a new network reduction methodology is developed for multi‐port connections utilizing the analogy between electrical circuits and hydraulic networks. The equivalent simple network is obtained by suitably applying the generalized Thevenin theorem for electrical circuits. The number of network elements in the equivalent network is significantly reduced compared to the ones obtained by the existing water distribution network (WDN) reduction methods. Therefore, it is possible to reorganize and expand a large existing network system from a prior knowledge of its most sensitive parts. The accuracy and robustness of the proposed methodology are investigated on realistic WDNs by comparing the results with EPANET, for both Demand Driven Analysis and Pressure Driven Analysis. However, as of now, an electrical simulator is required to implement the proposed methodology due to the absence of current dependent voltage source model in hydraulic simulators. The proposed network reduction method can be of enormous utility for hydraulic engineers and opens up an opportunity to implement new elements in hydraulic simulators. Plain Language Summary: Rapid urbanization requires the existing water distribution network to be reorganized or expanded. The extended network requires multiple simulations for optimal design considering various constraints such as cost, variable nodal demands, etc. For this purpose, a computationally efficient network is required to be generated using a network reduction method. The practicing hydraulic engineers frequently use the reservoir‐pump model to replace an existing network. But such a model should be applied when the networks are connected through a single pipe. The present study explores the application of the Thevenin theorem for electrical circuits to reduce an existing network. The main advantage of this method is that the number of reduced network elements is significantly less than the ones obtained by applying any other existing water distribution network (WDN) reduction methods. The Thevenin network is then connected to the sub‐network planned for the expanded region for analysis. The accuracy and robustness of the proposed network reduction methodology are investigated on realistic WDNs by comparing the results with the established hydraulic simulator, EPANET. The proposed methodology can be a handy tool for hydraulic engineers to reorganize and expand existing WDN to new areas. Key Points: The concept of equivalent network is used for expansion and reorganization of a large water distribution networkAn analogy between electrical circuits and hydraulic pipe networks is utilized to reduce large water distribution networksThe reduced network can be connected to sub‐networks for detailed analysis without sacrificing accuracy [ABSTRACT FROM AUTHOR]

A steeper fall of fusion excitation function, compared to the predictions of coupled-channel (CC) models, at energies below the lowest barrier between the reaction partners, is termed as deep sub-barrier fusion hindrance. This phenomenon has been observed in many symmetric and nearly symmetric systems. Different physical origins of the hindrance have been proposed though a complete understanding is yet to be achieved. This work reports the measurement of the fusion (evaporation residue) cross sections for the system 19F+181Ta, from above the barrier down to the energies where fusion hindrance is expected to come into play. CC calculation with standard Woods–Saxon potential gives a fair description of the fusion excitation function down to energies ≃14% below the barrier. This is in contrast with the observation of increasing fusion hindrance in asymmetric reactions induced by increasingly heavier projectiles, viz. 6,7Li, 11B, 12C and 16O. The most likely reason for non-observation of fusion hindrance in the present system is the ‘softness’ of the collision partners. The ‘threshold’ for the onset of fusion hindrance in reactions involving well-deformed nuclei is expected to be at an energy lower than that estimated from the systematics. It is also noted that the asymmetric reactions, which have not shown any signature of fusion hindrance within the measured energy range, are induced by projectiles with low α-particle break-up threshold and have positive Q-values for most light particle pick-up channels. Since CC calculation reproduces the fusion excitation functions for these systems, probable roles of projectile break-up and particle transfer in fusion deep below the barrier are not conclusively proven. Further measurements and inclusion of break-up and transfer channels within the framework of CC formalism would be of interest. [ABSTRACT FROM AUTHOR]

Evaporation residue (ER) and fission cross sections were measured for the reaction O+ forming the compound nucleus 212Rn. Fission fragment angular distributions and anisotropies are consistent with the saddle point model predictions. Measured ER cross sections were fitted with statistical model calculations assuming shell-corrected free energy fission barrier height. The non-zero dissipation strength required to fit the ER cross section supports the dissipative nature of fission dynamics in heavy ion fusion. In the present study shell closure effects are not observed in the dissipation strength. [ABSTRACT FROM AUTHOR]

We measured giant dipole resonance (GDR) γ-rays in the 28Si + 116Cd reaction at ∼105 and 120 MeV excitation energies. The resonance widths were extracted as a function of temperature at different angular momentum values to decouple the effect of these two variables on resonance widths. The high energy GDR γ-rays from the decay of compound nucleus (CN) 144Sm were measured using a large NaI(Tl) detector in coincidence with a sum-spin multiplicity filter. The experimental data were analyzed under the framework of statistical decay of CN. The GDR cross sections were also calculated with a thermal shape fluctuation model (TSFM), which incorporates the temperature and spin dependent shell corrections within the Nilsson–Strutinsky approach. The GDR widths were extracted in the temperature range 1.5–2.2 MeV. The measured widths indicate that the increase of GDR widths with temperature at different average spin values follows a similar trend and is borne out by theoretical calculations. Present calculation shows that TSFM satisfactorily reproduces the GDR cross section as well as widths in the temperature range 1–2.2 MeV over a wide range of angular momentum. [ABSTRACT FROM AUTHOR]

Background: Intravenous adenosine has recently been used in the diagnosis of unexplained syncope, but there is no consensus as to the meaning of a ‘positive’ test. The objective is to determine the sensitivity and specificity of intravenous adenosine testing in the diagnosis of bradycardia-pacing indications [sinus node dysfunction(SND), atrio-ventricular block (AVB) and cardio-inhibitory carotid sinus syndrome (CSS)]. Design: Pilot cohort study. Methods: Patients—(i) Bradycardia-pacing group: Consecutive patients referred for pacing for SND, AVB and CSS; (ii) Consecutive head-up tilt (HUT)-positive VVS patients. Controls—(i) Simple controls (S-Con: normal examination/ECG) and (ii) Electrophysiology controls (EP-Con: consecutive subjects referred for accessory pathway ablation). Pacing referrals and EP-Con had electrophysiology studies to confirm referral diagnosis and exclude others. All subjects had bolus injection of 20 mg intravenous adenosine during continuous ECG and blood pressure monitoring (positive test: 6 s asystole, 10 s high-degree AVB post-injection). Sensitivity, specificity, safety and tolerability of the test were measured. Results: Of 264 potential participants (4 SND, 8 AVB, 7 CSS, 10 VVS, 10 EP-Con and 11 S-Con) 50 were studied. All (100%) of the bradycardia-pacing group were adenosine test-positive, as were 6 (60%) VVS. None (0%) and 3 (27%) of the EP- and S-Con groups were positive. Adenosine testing was 100% sensitive and 86% specific for bradycardia-pacing indications, and 100% specific using the diagnostically ‘clean’ EP-Con results. There were no significant adverse or side effects. Conclusions: Adenosine testing reliably identified patients with definitive bradycardia-pacing indications in whom alternative diagnoses were excluded. Further work is needed to evaluate the role of this test in the diagnosis of unexplained syncope. [ABSTRACT FROM AUTHOR]