Purbanchal University

The rapid adoption of electric vehicles (EVs) globally demands expanded charging infrastructure; however, their unplanned integration into radial distribution systems (RDS) often causes voltage instability, high power losses, and system inefficiencies. This study optimizes the placement and sizing of solar photovoltaic-battery system (PV-BESS) in Nepal's 30-bus Byasi feeder to mitigate these issues. Employing particle swarm optimization (PSO) and MATLAB/Simulink, the proposed approach reduces active power loss by 56.18 % (477 kW-209 kW) and improves minimum bus voltage by 2.57 % (0.9404-0.9646 p.u.) through integration of 2576 kW PV and 1311 kW BESS. The application of novel energy management strategy further curtails peak demand by 38.3 % (3700 kW-2283 kW). The solution achieves financial viability with approximately 9-year payback period. This research pioneers a comprehensive technical-operational-economic assessment for EV charging-oriented PV-BESS planning in Nepal's RDS, demonstrating how weighted multi-objective optimization balances power loss reduction and voltage improvement while ensuring economic feasibility. The findings provide a replicable framework for sustainable EV infrastructure development in similar distribution networks, highlighting the critical importance of strategic renewable energy integration for grid stability. The study's methodology and results offer valuable insights for utilities and policymakers addressing EV charging infrastructures challenges in developing power systems.

Sclerotium rolfsii Sacc. is a destructive soil-borne pathogen causing collar rot in chili (Capsicum spp.) and several other diseases in many economically important crops. This study evaluated the efficacy of nine fungicides representing different chemical classes (triazoles, strobilurins, benzimidazoles, dithiocarbamates, and contact fungicides) against S. rolfsii using the poisoned food technique under in vitro conditions at 25, 50, and 100 parts per million (ppm) concentrations. Most systemic fungicides significantly inhibited mycelial growth compared to the untreated control, whereas captan, copper oxychloride, and mancozeb showed poor inhibition at lower concentrations. The highest inhibition of mycelial growth over control was observed with carboxin + thiram (91.25

On 26 August 2026 a rock–ice avalanche on the north face of Langtang Lirung, Nepal, initiated a debris flow and flood that ran roughly 100 km down the Lhende Khola, Bhote Koshi and Trishuli. Several contemporaneous reports asserted that satellite radar had tracked a month of accelerating slope movement before failure; that assertion has not been substantiated in published analysis. Using Copernicus Sentinel-1 IW GRD amplitude on a single relative orbit, this note (i) locates the failure independently and (ii) tests directly for a precursory signal. Co- and cross-polarised change between 16 and 28 August is concentrated on the reported detachment coordinate: within 500 m, 30.0% of VV pixels and 25.4% of VH pixels changed by more than 6 dB, against 0.8% and 0.4% respectively across the remainder of a 308 km² scene. Across five pre-event passes from 29 June to 16 August, measured against 80 terrain-matched control patches, VV shows a nominally significant negative trend (−0.20 ± 0.03 dB cycle⁻¹ across independent control draws, p ≈ 0.02) that is produced entirely by the first scene of the series; excluding it, the remaining four dates are flat (+0.01 dB cycle⁻¹, p = 0.99). VH shows a monotonic rise (+0.62 ± 0.03 dB cycle⁻¹, p < 0.01, robust to exclusion of either endpoint) which is rejected by a same-orbit seasonal baseline: in 2025 the equivalent rise occurred earlier and had completed by late June, whereas in 2026 the face was 3.05 dB below the 2025 plateau at the same date and subsequently rose 2.87 dB. The apparent precursor is the completion of a delayed seasonal transition. No precursory signal is present in the freely available amplitude record at 12-day sampling; the detection limit is approximately 1 dB of progressive change over two months.

On 26 August 2026 a rock–ice avalanche detached from Langtang Lirung, Nepal, and released a debris flood that crossed the Nepal–China border. Deformation preceding the failure has since been reported from a multi-month Sentinel-1 stack, and pre-event indications have been identified in commercial optical imagery. Both analyses began from a known failure location. This paper asks a different question: what routine, freely available Sentinel-1 products contained at the last acquisition before failure, and how large a signal would have had to be before they contained something. Three quantities are tested on a 500 m disc over the detachment — backscatter amplitude, interferometric coherence, and line-of-sight displacement from unwrapped phase — each against 120 control discs in the same scene matched on local incidence angle, aspect and slope, and against the source’s own history over the preceding two months. The last usable descending acquisition precedes failure by 50.6 hours. No quantity distinguishes the source from comparable slopes or from its own quiet behaviour: amplitude at the 67.5th percentile of controls, coherence third of five quiet intervals, cumulative displacement at the 31st percentile. The same statistics identify the collapse decisively once it falls inside the observation interval, at z = 4.57 in coherence and below all 120 controls in amplitude, so these are calibrated limits rather than uninformative nulls. No surface disturbance above approximately 2 ha of coherent decorrelation occurred in the twelve days ending 50.6 hours before failure, and no line-of-sight displacement above approximately 13 mm per month occurred over the preceding seven weeks. That bound lies above the rate reported from the multi-month stack, which is the substantive result: the deformation was measurable from orbit using free archived data, but not by the twelve-day products a monitoring service would have been screening.

A negative result from satellite radar — "no precursory deformation was detected" — carries no information unless the range of signals the measurement could have detected is reported alongside it. We measure that range at two rock–ice avalanche sources, Langtang Lirung, Nepal (2026) and Ronti Peak, India (2021), using a single procedure, and identify four determinants of it that are site-specific and not predictable from the sensor specification. Viewing geometry cannot be selected on usable-pixel fraction, the quantity most easily computed before processing: at Langtang an ascending track covering 100 per cent of the source disc has 4.1 times the variance of a descending track covering 44 per cent, and the failure is invisible on the former (z = −0.52) while the latter registers it at z = +3.65. The limiting seasonal term is variance rather than offset, and so cannot be detrended away: nine same-window February controls at Ronti span 6.95 to 32.11 per cent of the source disc below a coherence threshold, a range wider than any plausible precursor. Control design does not transfer; the published 120-disc scheme admits 46 candidates at Ronti, aspect-limited. And the upper bound is rarely stated at all. Placed against the half-fringe unwrapping limit of a 12-day pair, no published precursory detection we examined lies inside the range a single pair can measure — three sit at or below its floor, three at or above its ceiling, and every one was obtained by multi-epoch inversion accumulated over years rather than from the routine product. Neither event is detectable at its source in routine 12-day C-band products, for opposite reasons: one below the precision floor, one above the unwrapping ceiling. The sensitivity range is bounded at both ends, both bounds are site-specific and differ by an order of magnitude between sites of the same hazard class, and a null reported without them is not interpretable.