Non-reflexive Nonsense: Proof-Theory for Paracomplete Weak Kleene Logic

Our aim is to provide a sequent calculus whose external consequence relation coincides with the three-valued paracomplete logic `of nonsense' introduced by Dmitry Bochvar and, independently, presented as the weak Kleene logic K3W by Stephen C. Kleene. The main features of this calculus are (i) that it is non-reflexive, i.e., Identity is not included as an explicit rule (although a restricted form of it with premises is derivable); (ii) that it includes rules where no variable-inclusion conditions are attached; and (iii) that it is hybrid, insofar as it includes both left and right operational introduction as well as elimination rules

Conjunction and Disjunction in Infectious Logics

In this paper we discuss the extent to which conjunction and disjunction can be rightfully regarded as such, in the context of infectious logics. Infectious logics are peculiar many-valued logics whose underlying algebra has an absorbing or infectious element, which is assigned to a compound formula whenever it is assigned to one of its components. To discuss these matters, we review the philosophical motivations for infectious logics due to Bochvar, Halldén, Fitting, Ferguson and Beall, noticing that none of them discusses our main question. This is why we finally turn to the analysis of the truth-conditions for conjunction and disjunction in infectious logics, employing the framework of plurivalent logics, as discussed by Priest. In doing so, we arrive at the interesting conclusion that —in the context of infectious logics— conjunction is conjunction, whereas disjunction is not disjunction

Modeling the interaction of computer errors by four-valued contaminating logics

Logics based on weak Kleene algebra (WKA) and related structures have been recently proposed as a tool for reasoning about flaws in computer programs. The key element of this proposal is the presence, in WKA and related structures, of a non-classical truth-value that is “contaminating” in the sense that whenever the value is assigned to a formula ϕ, any complex formula in which ϕ appears is assigned that value as well. Under such interpretations, the contaminating states represent occurrences of a flaw. However, since different programs and machines can interact with (or be nested into) one another, we need to account for different kind of errors, and this calls for an evaluation of systems with multiple contaminating values. In this paper, we make steps toward these evaluation systems by considering two logics, HYB1 and HYB2, whose semantic interpretations account for two contaminating values beside classical values 0 and 1. In particular, we provide two main formal contributions. First, we give a characterization of their relations of (multiple-conclusion) logical consequence—that is, necessary and sufficient conditions for a set Δ of formulas to logically follow from a set Γ of formulas in HYB1 or HYB2 . Second, we provide sound and complete sequent calculi for the two logics

Landslide phenomenon in watered geological sediments in the closed outcrop of the Piaseczno Sulfur Mine

Wyrobisko Piaseczno, po wyłączeniu pompowania wód podziemnych w rejonie Machowa, jest obecnie najniżej położonym ośrodkiem drenażowym w rejonie Tarnobrzega. Niestety, przynosi to niepożądane skutki w postaci występowania znaczącego gradientu ciśnienia wód podziemnych w otoczeniu wyrobiska. Napływ wód podziemnych zakłóca warunki równowagi stateczności skarp i zboczy wyrobiska, które uformowano w warunkach lądowych. Zmiana zawodnienia utworów geologicznych w obrębie wyrobiska powoduje nasilenie niepożądanych zjawisk osuwiskowych. Stanowią one zagrożenie dla otoczenia wyrobiska, jego przyszłych użytkowników, a obecnie także dla pracującej w obrębie odkrywki załogi. Wyniki analizy warunków stateczności pozwalają stwierdzić, że odwodnienie skarp metodą bezwykopową poprawi warunki geotechniczne. Obliczenia wskazują, że wartość wskaźnika stateczności po zastosowaniu drenażu poziomego wzrośnie od kilku do kilkudziesięciu procent. Zaletą proponowanego rozwiązania likwidacji zjawisk osuwiskowych metodą bezwykopową jest grawitacyjny, bezkosztowy sposób odprowadzenia wody do zbiornika Piaseczno. Po wykonaniu otworów drenażowych koszty utrzymania systemu odprowadzenia wody ze skarp ograniczą się do serwisowania otworów oraz ich ewentualnej renowacji za pomocą metod stosowanych powszechnie w technice sanitarnej. Przyjęty wodny kierunek rekultywacji wyrobisk spowoduje powstanie zbiornika wodnego o powierzchni lustra wody około 160 ha, dodatkowo pełniącego funkcję rekreacyjno-sportową.The Piaseczno outcrop it is the lowest drainage center in the region of Tarnobrzeg. This brings undesirable consequences such as a significant pressure gradient of groundwater in the vicinity of the outcrop The inflow of groundwater disturbs the equilibrium conditions of the escarpments and slopes, which was formed under the land conditions. As a result, the dangerous phenomenon known as a landslide occur within the outcrop. The results of analysis of stability conditions indicate that the dehydration of escarpments using trenchless methods improves the geotechnical conditions. The value of indicator stability will increase from several to several dozen percent after applying horizontal drainage. An advantage of the proposed trenchless method is also the gravitational, cost-free discharge of water to the Piaseczno reservoir. After the drainage holes, the costs of drainage system of escarpments will be limited only to the maintenance of holes (eventually renovation) by methods commonly used in sanitary techniques. The water reclamation of outcrops will lead to the forming of a water reservoir with an area of 160 ha. It will also serve as a sport and recreation area

Liquidation of "Piaseczno" excavation - water basin construction

Po zakończonej eksploatacji siarki w wyrobisku "Piaseczno" bardzo ważnym etapem jest zabezpieczenie wyrobiska górniczego. Podczas projektowania rozważone zostały różne koncepcje jego likwidacji, wybrano opcję, w ramach której prace zabezpieczające zmierzają do powstania zbiornika wodnego, który wraz z rekultywowanymi terenami otaczającymi (pogórniczymi) zostanie zagospodarowany w kierunku rekreacyjnym. Podstawowym celem jest przywrócenie wartości użytkowych terenom przekształconym wieloletnią działalnością górniczą. Dla wyrobiska w "Piasecznie" przyjęty został wodny kierunek rekultywacji o charakterze rekreacyjnym, natomiast dla zwałowiska wewnętrznego oraz obrzeży zadrzewieniowo-łąkowy o charakterze rekreacyjnym.After the end of exploitation of mining excavation, an important stage was its safeguard. For that reason different conceptions of realization were considered at the design stage. The initial liquidation of excavation and also safety works have been conducted intensively since 2005 and have aimed water basin construction, which will be developed for recreation with the post-mining land. Restoration of the area, which was dewastated by the long-term mining activity, is the fundamental aim

Silver nanoparticles deposited on calcium hydrogenphosphate – silver phosphate matrix; biological activity of the composite

The composite containing nanosilver uniformly deposited on matrix composed of CaHPO4  x 2H2 O (brushite, ca 89 mass %), CaHPO4  (monteonite, ca 9.5 mass%), and Ag3 PO4  (0.5 mas%) was obtained by addition of calcium nitrate and silver nitrate aqueous solution at 30:1 Ca:Ag molar ratio into excess of (NH4 )2 PO4  solution at pH 5.0 – 5.5. The isolated solid was characterized by STEM, XRD, and LDI mass spectrometry. It has been found that nanosilver was uniformly distributed within composite as 3 PO4  as identified by XRD method. The composite showed strong growth inhibition in E. coli and P. aeruginosa strains, and moderate towards S. aureus. The C. albicans cells were the most resistant to the tested material, although still composite was moderately cytostatic for the yeast

Modeling the Interaction of Computer Errors by Four-Valued Contaminating Logics

Logics based on weak Kleene algebra (WKA) and related structures have been recently proposed as a tool for reasoning about flaws in computer programs. The key element of this proposal is the presence, in WKA and related structures, of a non-classical truth-value that is “contaminating” in the sense that whenever the value is assigned to a formula φ, any complex formula in which φ appears is assigned that value as well. Under such interpretations, the contaminating states represent occurrences of a flaw. However, since different programs and machines can interact with (or be nested into) one another, we need to account for different kind of errors, and this calls for an evaluation of systems with multiple contaminating values. In this paper, we make steps toward these evaluation systems by considering two logics, HYB1 and HYB2, whose semantic interpretations account for two contaminating values beside classical values 0 and 1. In particular, we provide two main formal contributions. First, we give a characterization of their relations of (multiple-conclusion) logical consequence—that is, necessary and sufficient conditions for a set Δ of formulas to logically follow from a set Γ of formulas in HYB1 or HYB2. Second, we provide sound and complete sequent calculi for the two logics

Silver nanoparticles deposited on calcium hydrogenphosphate – silver phosphate matrix; biological activity of the composite

The composite containing nanosilver uniformly deposited on matrix composed of CaHPO4  x 2H2 O (brushite, ca 89 mass %), CaHPO4  (monteonite, ca 9.5 mass%), and Ag3 PO4  (0.5 mas%) was obtained by addition of calcium nitrate and silver nitrate aqueous solution at 30:1 Ca:Ag molar ratio into excess of (NH4 )2 PO4  solution at pH 5.0 – 5.5. The isolated solid was characterized by STEM, XRD, and LDI mass spectrometry. It has been found that nanosilver was uniformly distributed within composite as 3 PO4  as identified by XRD method. The composite showed strong growth inhibition in E. coli and P. aeruginosa strains, and moderate towards S. aureus. The C. albicans cells were the most resistant to the tested material, although still composite was moderately cytostatic for the yeast

Deterioration of Mechanical Properties of MBE-Grown, Metastable Semiconductor Layer with Time: the Case of Zinc Blende MnTe

Several few μm thick (001)-oriented, metastable MnTe layers with the zinc blende structure grown onto (001)GaAs substrate by MBE during different periods for the last twenty years were investigated by the scanning electron microscopy, atomic force microscopy, X-ray diffraction, and nanoindentation methods. A partial decomposition of the oldest investigated layers was demonstrated. An important decrease of Young's modulus from about 34 GPa to about 17 GPa, resulting from a deterioration of the crystal structure of such layers, was found