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

Structure and interpretation of computer programs

Publisher Summary This chapter discusses the mathematical theory of computation. Computation essentially explores how machines can be made to carry out intellectual processes. Any intellectual process that can be carried out mechanically can be performed by a general purpose digital computer. There are three established directions of mathematical research that are relevant to the science of computation—namely, numerical analysis, theory of computability, and theory of finite automata. The chapter explores what practical results can be expected from a suitable mathematical theory. Further, the chapter presents several descriptive formalisms with a few examples of their use and theories that enable to prove the equivalence of computations expressed in these formalisms. A few mathematical results about the properties of the formalisms are also presented.

A Basis for a Mathematical Theory of Computation

morphic function test. Good definitions help one to readily recognize which pattern to apply. There is also a well written section on inheritance related bugs, carried through to chapter 11 on testing reusable components. Table 11.1 shows the six languages compared with respect to performance across abstract and generic class. The advantage of Java over the others is apparent. Chapters 13 and 14 build subsystem test into system tests. Keep in mind that subsystem and system are defined by the author for his purpose. Chapter 15 is devoted to regression where regression is defined as once having passed a baseline test but now has a modified component. The system with modified component is said to be in need of regression testing. Section 4 Test Models is composed of chapters 16 through 19. The purpose of this section is to help the reader develop application specific test automation. Since it is application specific, it may be of limited value for those that fall outside the authors application set. The book is a little quirky in the way chapters are developed. Chapter 16 is only five pages long compared to chapter 10s 175 pages. The author takes literary license here , but perhaps allowance should be made for the complexity of the topic. Chapter 17 introduces a interesting concept of building in test code into the application. The author says that a assertion is a Boolean expression that defines the necessary conditions for correct execution. Basically these are checks and double checks, and they make good sense in some applications such as an operating system. To bolster this view the author gives some amazing statistics on IBMs OS/400 operating system. Chapter 18 is on test oracles. A test oracle is a code fragment of a test code system that produces the results of a test case. An oracle is something that can be trusted to deliver the expected results. Several patterns of oracles are discussed from parametric to gold. He foes on to tackle automated test result evaluation. Some of these concepts make sense for a trusted operating system but not for an application running under a trusted OS but the author does not make that distinction. Chapter 19 is on the topic of test harness design. A test harness is the nomenclature of a set that contains test case, test suites, stubs, drivers and control systems. This is all the elements …

Theories of programming languages

Declarative programming languages advocate a programming style expressing the properties of problems and their solutions rather than how to compute individual solutions Depending on the underlying formalism to express such properties, one can distinguish different classes of declarative languages, like functional, logic, or constraint programming languages This paper surveys approaches to combine these different classes into a single programming language

/pdf/multi-paradigm-declarative-languages-4p36bxl5x6.pdf

Multi-paradigm declarative languages

Non-confluent and non-terminating rewrite systems are interesting from the point of view of programming In particular, existing functional logic languages use such kind of rewrite systems to define possibly non-strict non-deterministic functions The semantics adopted for non-determinism is call-time choice, whose combination with non-strictness is not a trivial issue that has been addressed from a semantic point of view in the Constructor-based Rewriting Logic (CRWL) framework We investigate here how to express call-time choice and non-strict semantics from a point of view closer to classical rewriting The proposed notion of rewriting uses an explicit representation for sharing with let-constructions and is proved to be equivalent to the CRWL approach Moreover, we relate this let-rewriting relation (and hence CRWL) with ordinary rewriting, providing in particular soundness and completeness of let-rewriting with respect to rewriting for a class of programs which are confluent in a certain semantic sense

http://gpd.sip.ucm.es/fraguas/papers/PPDP07.pdf

A simple rewrite notion for call-time choice semantics

How to extract negative information from programs is an important issue in logic programming. Here we address the problem for functional logic programs, from a proof-theoretic perspective. The starting point of our work is CRWL (Constructor based ReWriting Logic), a well established theoretical framework for functional logic programming, whose fundamental notion is that of non-strict non-deterministic function. We present a proof calculus, CRWLF, which is able to deduce negative information from CRWL-programs. In particular, CRWLF is able to prove finite failure of reduction within CRWL.

A Proof Theoretic Approach to Failure in Functional Logic Programming

It is known that the behavior of non-deterministic functions with call-time choice semantics, present in current functional logic languages, is not well described by usual approaches to reduction like ordinary term rewriting systems or λ-calculus. The presence of HO features makes things more difficult, since reasoning principles that are essential in a standard (i.e., deterministic) functional setting, like extensionality, become wrong. In this paper we propose HOlet-rewriting, a notion of rewriting with local bindings that turns out to be adequate for programs with HO non-deterministic functions, as it is shown by strong equivalence results with respect to HOCRWL, a previously existing semantic framework for such programs. In addition,we give a sound and complete notion of HO-let-narrowing, we show by a case study the usefulness of the achieved combination of semantic and reduction notions, and finally we prove within our framework that a standard approach to the implementation of HO features, namely translation to FO, is still valid for HO nondeterministic functions.

http://gpd.sip.ucm.es/fraguas/papers/FLOPS08-Springer.pdf

Rewriting and call-time choice: the HO case

How to extract negative information from programs is an important issue in logic programming. Here we address the problem for functional logic programs, from a proof-theoretic perspective. The starting point of our work is CRWL (Constructor based ReWriting Logic), a well established theoretical framework for functional logic programming, whose fundamental notion is that of non-strict non-deterministic function. We present a proof calculus, CRWLF, which is able to deduce negative information from CRWL-programs. In particular, CRWLF is able to prove ‘finite’ failure of reduction within CRWL.

A proof theoretic approach to failure in functional logic programming

Functional-logic programming amalgamates some of the main features of both functional and logic styles into a single paradigm. Nevertheless, negation is a widely investigated feature in logic programming that has not received much attention in such programming style. It is not difficult to incorporate some kind of negation as finite failure for ground goals, but we are interested in a constructive version able to deal with non-ground goals. With this aim, in previous works we have built a formal framework for checking (finite) failure of reduction. In this paper we adapt it for im- plementing a prototype for a functional-logic language with constructive failure as the natural counterpart to negation in logic programming.

/pdf/constructive-failure-in-functional-logic-programming-from-4z6cn6l8um.pdf

Jaime Sánchez-Hernández

Papers

A simple rewrite notion for call-time choice semantics

A Proof Theoretic Approach to Failure in Functional Logic Programming

Rewriting and call-time choice: the HO case

A proof theoretic approach to failure in functional logic programming

Constructive Failure in Functional-Logic Programming: From Theory to Implementation.