•We formalize the notion of assignments and assignment strategies.•We present an SMT encoding from which assignment strategies are extracted.•We define a sound decomposition of a TLA+ formula into ...symbolic transitions.•We implement the above as part of the APALACHE model checker.•We present experimental results using several state-of-the-art TLA+ specifications.
In ▪, a system specification is written as a logical formula that restricts the system behavior. As a logic, ▪ does not have assignments and other imperative statements that are used by model checkers to compute the successor states of a system state. Model checkers compute successors either explicitly — by evaluating program statements — or symbolically — by translating program statements to an SMT formula and checking its satisfiability. To efficiently enumerate the successors, TLA's model checker TLC introduces side effects. For instance, an equality x′=e is interpreted as an assignment of e to the yet unbound variable x.
Inspired by TLC, we introduce an automatic technique for discovering expressions in ▪ formulas such as x′=e and x′∈{e1,…,ek} that can be provably used as assignments. In contrast to TLC, our technique does not explicitly evaluate expressions, but it reduces the problem of finding assignments to the satisfiability of an SMT formula. Hence, we give a way to slice a ▪ formula in symbolic transitions, which can be used as an input to a symbolic model checker. Our prototype implementation successfully extracts symbolic transitions from a few ▪ benchmarks.
is an intracellular parasite of all mammals and birds, responsible for toxoplasmosis. In healthy individuals
infections mostly remain asymptomatic, however this parasite causes severe morbidity and ...mortality in immunocompromised patients and congenital toxoplasmosis in pregnant women. The consumption of raw or undercooked pork is considered as an important risk factor to develop toxoplasmosis in humans. Since effective therapeutic interventions to treat toxoplasmosis are scarce, vaccination of meat producing animals may prevent
transmission to humans. Here, we evaluated the elicited immune responses and the efficacy of a potential vaccine candidate, generated by size fractionation of
lysate proteins, to reduce the parasite burden in tissues from experimentally
infected pigs as compared to vaccination with total lysate antigens (TLA). Our results show that both the vaccine candidate and the TLA immunization elicited strong serum IgG responses and elevated percentages of CD4
CD8
IFNγ
T cells in
infected pigs. However, the TLA vaccine induced the strongest immune response and reduced the parasite DNA load below the detection limit in brain and skeletal muscle tissue in most animals. These findings might inform the development of novel vaccines to prevent
infections in livestock species and humans.
Na območju Triglavskega narodnega parka zasledimo poseben tip travnikov – grbinaste travnike. Zaradi človekove dejavnosti imajo grbinasti travniki ne le naravovarstveno, ampak tudi kulturno vrednost. ...Zato je od leta 2004 v Programu razvoja podeželja (PRP) vzpostavljen sistemski ukrep za ohranjanje grbinastih travnikov. Kmetje so za njihovo vzdrževanje upravičeni do izravnalnih plačil, a je ta podpora nizka, med manj poznanimi in zelo slabo uveljavljenimi. Uradni prostorski sloj grbinastih travnikov je, kljub terenski preveritvi in nadgradnji v letu 2021, necelovit in deloma pomanjkljiv. Namen članka je prikaz nove metode oziroma razvoja kvantitativnega postopka identifikacije grbinastih travnikov na območju Triglavskega narodnega parka. Omejitev postopka je, da ni neposredno uporaben za zaznavanje grbinastih travnikov brez naknadnega terenskega ali digitalnega pregleda. Z njegovo uporabo smo predstavili možnost učinkovite nadgradnje obstoječega uradnega prostorskega sloja grbinastih travnikov.
Direct drive tubular linear actuators (TLAs) may be used in various applications that require fast movements and high-precision positioning, e.g., pick-and-place robots. This article presents the ...analysis, dynamic electromechanical model derivation, controller design, and system operation of a TLA with integrated magnetic bearings (MBs). Furthermore, the actuator operation is verified with extensive measurements on the prototype, which include axial position step response, standard deviation of the steady-state positions and mover tilting control. Compared with any conventional TLA, which may perform only linear motion, the mover tilting control is possible due to integrated MBs. This gives the new actuator a great advantage in high-precision positioning systems, since any thermal expansions of the parallel kinematics may be compensated.
Cilj ovog rada bio je utvrditi sastav humusa u antropogenim tlima unutar različitih agroekoloških uvjeta Istre. Istraživanje je provedeno 2020. godine na tri tipa tla: terasirano tlo, amfiglej i ...oranično tlo iz crvenice. Sa svake lokacije uzeti su uzorci tla iz oraničnog (0-30 cm) i podoraničnog sloja (30-50 cm), u 5 ponavljanja. Optička gustoća alkalnog ekstrakta humusnih tvari (E4/E6) određena je spektrofotometrijski (VIS). Prosječni sadržaj huminskih kiselina (HA) u oraničnom sloju tla snižavao se kako slijedi: amfiglej (0,58%) > oranično tlo iz crvenice (0,53%) > terasirano tlo (0,26%). U podoraničnom sloju tla najviše je HA u amfigleju (0,48%), potom u oraničnom tlu iz crvenice (0,40%), a najmanje u terasiranom tlu (0,11%). Odnos HA/FA u oba sloja istraživanih tala opadao je kako slijedi: oranično tlo iz crvenice (2,28 i 1,49) > amiglej (1,11 i 1,09) > terasirano tlo (0,39 i 0,34). U oraničnom sloju E4/E6 povećavao se kako slijedi: Oranično tlo iz crvenice (1,28) < amfiglej (1,31) < terasirano tlo (4,69), a u podoraničnom sloju: amfiglej (1,43) < oranično tlo iz crvenice (1,64) < Terraced soil (4,83) U terasiranom tlu s HA/FA < 1 i E4/E6 > 4 prevladavale su fulvo kiseline alifatske strukture i male molekulske mase, što je pokazatelj loše kakvoće humusa. U amfigleju i oraničnom tlu iz crvenice s HA/FA > 1 i E4/E6 < 4 prevladavale su aromatske, visokopolimerizirane molekulske strukture, odnosno humus je bolje kvalitete.
Tasks in modular proofs of concurrent algorithms Castañeda, Armando; Hurault, Aurélie; Quéinnec, Philippe ...
Information and computation,
June 2023, 2023-06-00, 2023-06, Letnik:
292, Številka:
Selected papers from SSS’2019, the 21st International Symposium on Stabilization, Safety, and Security of Distributed Systems
Journal Article
Recenzirano
Odprti dostop
Proving the correctness of distributed or concurrent algorithms is a complex process. Errors in the reasoning are hard to find, calling for computer-checked proof systems like Coq or TLA+. To use ...these tools, sequential specifications of base objects are required to build modular proofs by composition. Unfortunately, many concurrent objects lack a sequential specification. This article describes a method to transform any task, a specification of a concurrent one-shot distributed problem, into a sequential specification involving two calls, set and get. This enables designers to compose proofs, facilitating modular computer-checked proofs of algorithms built using tasks and sequential objects as building blocks. Moir & Anderson implementation of renaming using splitters, wait-free concurrent objects, is an algorithm designed by composition, but it is not modular. Using our transformation, a modular description of the algorithm is given in TLA+ and mechanically verified using the TLA+ Proof System. As far as we know, this is the first time this algorithm is mechanically verified.
Istraživan je utjecaj različitih sustava obrade tla i korištenja slame kao malča te njihove interakcije na prinos i agronomska svojstva jare pšenice. Pokus je postavljen u sjeverozapadnoj Hrvatskoj ...na fluvioslu u humidnim uvjetima 2021. godine s tri sustava obrade tla (glavni faktor): konvencionalna obrada s oranjem do 20 cm u jesen i tanjuranjem u proljeće (CT), primjena kombiniranog oruđa do 15 cm u proljeće (MT), podrivanje na dubinu 35-40 cm u jesen te rahljenje kombiniranim oruđem do 15 cm u proljeće (RT). Svaki sustav obrade podijeljen je na parcele sa i bez slame kao podfaktorom pokusa. Obrada tla imala je značajan učinak (p<0,05) samo za hektolitarsku masu, dok je značajan učinak korištenja malča zabilježen za masu 1000 zrna i sedimentacijsku vrijednost. Interakcija obrade i slame pokazala je značajan učinak na sva istraživana svojstva (prinos, masa 1000 zrna, hektolitarska masa, sadržaj proteina, sadržaj vlažnog lijepka, sedimentacijska vrijednost). Prema dobivenim rezultatima može se zaključiti da se plitkom obradom (MT) ostvaruje zadovoljavajući prinos u odnosu na konvencionalnu obradu, ali je za optimizaciju kemijskih karakteristika prinosa jare pšenice potrebno testirati i druge agrotehničke mjere.
This paper presents the influence of different tillage systems and the use of straw as mulch and their interaction on yield and yield components (physical and chemical) of spring wheat. The experiment was established in northwestern Croatia on alluvial soils under humid conditions with three tillage systems (main factor): conventional tillage with plowing up to 20 cm in autumn and disc harrowing in spring (CT), use of multitiller up to 15 cm in spring (MT); subsoiling to a depth of 35-40 cm in autumn and loosening with multitiller up to 15 cm in spring (RT). Each tillage system has subplots with and without straw. The tillage factor had a significant effect (p < 0.05) only on hectolitre mass, while a significant effect of mulch use was observed on 1000-kernel weight and sedimentation value. The interaction of these factors had a significant effect on all the components studied (yield, 1000-kernel weight, hectolitre mass, protein content, wet gluten content, sedimentation value). From the short-term results obtained, it can be concluded that shallow tillage (MT) gives satisfactory yield compared to conventional tillage, but further optimization of the agrotechnical system is required to improve the chemical properties
TRENUTNO STANJE MODELA MEHANIKE TLA Đurin, Bojan; Kancijan, Matija; Aniskin, Aleksej ...
e-Zbornik, elektronički zbornik radova Građevinskog fakulteta,
12/2022, Letnik:
12, Številka:
24
Journal Article
Recenzirano
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Prilikom projektiranja geotehničkih građevina, postoji potreba za usvajanjem određenog modela kojim ćemo predstaviti tlo koje promatramo pod određenim opterećenjem. Parametri koje zadajemo tome tlu ...ponekad su nepotpuni, čemu su uzrok razni problemi poput nepotpunih podataka iz laboratorija ili terenskog (“in situ”) istraživanja. Odabir pravilnog modela ovisi o tome koliku točnost izračuna želimo dobiti, odnosno koliku nam ulogu igra rizik i do koje granice možemo prihvatiti možda neka rješenja koja ne daju pravu sliku o ponašanju tla pod opterećenjem. Zato je pravilan odabir modela prvi korak pri rješavanju geotehničkih zadaća, o čemu će nam ovisiti sav daljnji rad.
•The SBR and TLA compound modified binders had better low-temperature flow properties than TLA single modified binders did.•The concentration combination of 2% SBR and 20% TLA was recommended.•The ...workability was degraded by introducing additives but all the studied binders met the Superpave specification.
A comprehensive experiment involving different Trinidad Lake Asphalt (TLA) and Styrene–Butadiene–Rubber (SBR) compound modified binders was conducted to investigate the rheological and aging properties of TLA and SBR compound modified binders. Four TLA (5%, 10%, 20%, and 30%) and four SBR concentrations (0%, 2%, 3%, and 4%) were selected. Dynamic shear rheometer (DSR) and bending beam rheometer (BBR) tests were performed to evaluate the rheological properties. Conventional tests (penetration, softening point, and ductility tests) were conducted on TLA and SBR compound modified binders with different aging states (i.e., original, RTFO aged, and PAV aged) to investigate the physical and durability properties. Rotational viscosity tests were performed to evaluate the workability. The results indicated that compound modified binders with TLA and SBR could improve the deformation resistance of binders by increasing the early stiffness and prolong the service life of the corresponding pavement by improving the durability, compared with base asphalt binder. The addition of TLA could degrade the low-temperature flow properties, but the degradation effect could be offset by adding SBR. The combination of 2% SBR and 20% TLA was recommended based on the comprehensive analysis of test results. The workability was degraded by introducing additives, but all binders studied met the Superpave specification.
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