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This paper describes a study of welded steel plate joints using experimental and numerical methods. The objectives of this study are to observe the mechanical behavior of welded plate joints under monotonic and cyclic loads, identify their damage degradation processes, and provide useful test data for future damage analysis of beam-column connections in steel frame structures. Six specimens were designed, of which three were tested under monotonic loads, and the other three were tested under cyclic loads. The test setup consisted of three plates arranged in a cruciform and connected by two groove welds. The monotonic and cyclic loads were applied to the free end of the two outstanding plates, inducing a pulling force on the welded joint. Because the only element studied in the present work is the weld, the sizes of the three plates were kept constant. The responses of these welded plate joints are discussed in terms of their experimentally and numerically obtained mechanical parameters, hysteretic behavior, strain variations, stiffness degradation, damage process, and failure modes. The results show that the energy damage model outperforms the displacement damage model in terms of indicating the degree of damage. Furthermore, if designed according to code, all these welded plate joints perform satisfactorily.

A tower between two regular languages is a sequence of strings such that all strings on odd positions belong to one of the languages, all strings on even positions belong to the other language, and each string can be embedded into the next string in the sequence. It is known that if there are towers of any length, then there also exists an infinite tower. We investigate upper and lower bounds on the length of finite towers between two regular languages with respect to the size of the automata representing the languages in the case there is no infinite tower. This problem is relevant to the separation problem of regular languages by piecewise testable languages.

AbstractReview: 141 refs.

Facultative paedomorphosis is an environmentally induced polymorphism that is well known for many caudate species including newts. Although facultative paedomorphosis has been documented in some smooth-newt populations, records of entirely paedomorphic populations outside the Balkans are limited. Here we present the first evidence of a paedomorphic population of the smooth newt in the Czech Republic with discussion of potential causes that need to be further tested. Acta Herpetologica, Vol 8 No 1 (2013)

Temperate grasses belonging to the Festuca–Lolium complex are important throughout the world in pasture and grassland agriculture. Tall fescue (Festuca arundinacea Schreb.) is the predominant species in the United States, covering approximately 15 million ha. Tall fescue has distinctive morphotypes, two of which are Continental (summer active) and Mediterranean (summer semidormant). This is the first report of a linkage map created for Mediterranean tall fescue, while updating the Continental map with additional simple sequence repeat and sequence‐tagged site markers. Additionally, this is the first time that diversity arrays technology (DArT) markers were used in the construction of a tall fescue map. The male parent (Continental), R43‐64, map consisted of 594 markers arranged in 22 linkage groups (LGs) and covered a total of 1577 cM. The female parent (Mediterranean), 103‐2, map was shorter (1258 cM) and consisted of only 208 markers arranged in 29 LGs. Marker densities for R43‐64 and 103‐2 were 2.65 and 6.08 cM per marker, respectively. When compared with the other Poaceae species, meadow fescue (F. pratensis Huds.), annual ryegrass (L. multiflorum Lam.), perennial ryegrass (L. perenne L.), Brachypodium distachyon (L.) Beauv., and barley (Hordeum vulgare L.), a total of 171 and 98 orthologous or homologous sequences, identified by DArT analysis, were identified in R43‐64 and 103‐2, respectively. By using genomic in situ hybridization, we aimed to identify potential progenitors of both morphotypes. However, no clear conclusion on genomic constitution was reached. These maps will aid in the search for quantitative trait loci of various traits as well as help define and distinguish genetic differences between the two morphotypes.

A relationship between the heliospheric magnetic field, atmospheric electric field, lightning activity, and secondary cosmic rays measured on the high mount of Lomnický Štít (2,634 m a.s.l.), Slovakia, during the declining phase of the solar cycle 24 is investigated with a focus on variations related to solar rotation (about 27 days). The secondary cosmic rays are detected using a neutron monitor and the detector system SEVAN, which distinguishes between different particles and energies. Using spectral analysis, we found distinct ∼27-day periodicities in variations of Bx and By components of the heliospheric magnetic field and in pressure-corrected measurements of secondary cosmic rays. The 27-day variations of secondary cosmic rays, on average, advanced and lagged the variations of Bx and By components by about 40° and −140°, respectively. Distinct 27-day periodicities were found both in the neutron monitor and the SEVAN upper and middle detector measurements. A nondominant periodicity of ∼27 days was also found for lightning activity. A cross-spectral analysis between fluctuation of the lightning activity and fluctuation of the heliospheric magnetic field (HMF) showed that fluctuation of the lightning activity was in phase and in antiphase with Bx and By components of the HMF, respectively, which is in agreement with previous studies investigating the influence of solar activity on lightning. On the other hand, the ∼27-day periodicity was not significant in the atmospheric electric field measured in Slovakia and Czechia. Therefore, no substantial influence of Bx and By on the atmospheric electric field was observed at these middle-latitude stations.

The international collaboration designing and constructingthe Deep Underground Neutrino Experiment (DUNE) at the Long-BaselineNeutrino Facility (LBNF) has developed a two-phase strategy towardthe implementation of this leading-edge, large-scale scienceproject. The 2023 report of the US Particle Physics ProjectPrioritization Panel (P5) reaffirmed this vision and stronglyendorsed DUNE Phase I and Phase II, as did the European Strategy forParticle Physics. While the construction of the DUNE Phase I is wellunderway, this White Paper focuses on DUNE Phase II planning. DUNEPhase-II consists of a third and fourth far detector (FD) module, anupgraded near detector complex, and an enhanced 2.1 MW beam. Thefourth FD module is conceived as a “Module of Opportunity”, aimedat expanding the physics opportunities, in addition to supportingthe core DUNE science program, with more advanced technologies. Thisdocument highlights the increased science opportunities offered bythe DUNE Phase II near and far detectors, including long-baselineneutrino oscillation physics, neutrino astrophysics, and physicsbeyond the standard model.