Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

A Combinatory Logic

This article explores the use of non-idempotent intersection types in the framework of the λ-calculus. Different topics are presented in a uniform framework: head normalization, weak normalization, weak head normalization, strong normalization, inhabitation, exact bounds and principal typings. The reducibility technique, traditionally used when working with idempotent types, is replaced in this framework by trivial combinatorial arguments.

Non-idempotent intersection types for the Lambda-Calculus

We introduce and study the Bang Calculus, an untyped functional calculus in which the promotion operation of Linear Logic is made explicit and where application is a bilinear operation. This calculus, which can be understood as an untyped version of Call-By-Push-Value, subsumes both Call-By-Name and Call-By-Value lambda-calculi, factorizing the Girard's translations of these calculi in Linear Logic. We build a denotational model of the Bang Calculus based on the relational interpretation of Linear Logic and prove an adequacy theorem by means of a resource Bang Calculus whose design is based on Differential Linear Logic.

The Bang Calculus: an untyped lambda-calculus generalizing call-by-name and call-by-value

Call-by-value and call-by-need l-calculi are defined using the distinguished syntactic category of values. In theoretical studies, values are variables and abstractions. In more practical works, values are usually defined simply as abstractions. This paper shows that practical values lead to a more efficient process of substitution--for both call-by-value and call-by-need--once the usual hypothesis for implementations hold terms are closed, reduction does not go under abstraction, and substitution is done in micro steps, replacing one variable occurrence at the time. Namely, the number of substitution steps becomes linear in the number of β-redexes, while theoretical values only provide a quadratic bound.

https://hal.archives-ouvertes.fr/hal-01675373/document

On the Value of Variables

We first develop a (semantical) characterization of call-by-need normalization by means of typability, i.e. we show that a term is normalizing in call-by-need if and only if it is typable in a suitable system with non-idempotent intersection types. This first result is used to derive a new completeness proof of call-by-need w.r.t. call-by-name. Concretely, we show that call-by-need and call-by-name are observationally equivalent, so that in particular, the former turns out to be a correct implementation of the latter.

Reasoning About Call-by-need by Means of Types

We define two non-idempotent intersection type systems for the linear substitution calculus, a calculus with partial substitutions acting at a distance that is a computational interpretation of linear logic proof-nets. The calculus naturally express linear-head reduction, a notion of evaluation of proof nets that is strongly related to abstract machines. We show that our first (resp. second) quantitave type system characterizes linear-head, head and weak (resp. strong) normalizing sets of terms. All such characterizations are given by means of combinatorial arguments, i.e. there is a measure based on type derivations which decreases with respect to each reduction relation considered in the paper.

/pdf/quantitative-types-for-the-linear-substitution-calculus-kaz9iemiri.pdf

Quantitative Types for the Linear Substitution Calculus

The inhabitation problem for intersection types is known to be undecidable. We study the problem in the case of non-idempotent intersection, and we prove decidability through a sound and complete algorithm. We then consider the inhabitation problem for an extended system typing the λ-calculus with pairs, and we prove the decidability in this case too. The extended system is interesting in its own, since it allows to characterize solvable terms in the λ-calculus with pairs.

/pdf/the-inhabitation-problem-for-non-idempotent-intersection-4xxgfp3195.pdf

The Inhabitation Problem for Non-idempotent Intersection Types

We define two resource aware typing systems for the λμ-calculus based on non-idempotent intersection and union types. The non-idempotent approach provides very simple combinatorial arguments –based on decreasing measures of type derivations– to characterize head and strongly normalizing terms. Moreover, typability provides upper bounds for the length of head-reduction sequences and maximal reduction sequences. 1998 ACM Subject Classification F.4.1 Mathematical Logic

Types as Resources for Classical Natural Deduction.

Call-by-Push-Value (CBPV) is a programming paradigm subsuming both Call-by-Name (CBN) and Call-by-Value (CBV) semantics. The paradigm was recently modelled by means of the Bang Calculus, a term language connecting CBPV and Linear Logic.

Delia Kesner

Papers

Reasoning About Call-by-need by Means of Types

Quantitative Types for the Linear Substitution Calculus

The Inhabitation Problem for Non-idempotent Intersection Types

Types as Resources for Classical Natural Deduction.

The Bang Calculus Revisited