New Releases by Robert Harper

Stennesi Triadi is one of many human colonies that expanded throughout the stars in this sci-fi original. The planet''s previous inhabitants are an ancient and extinct alien civilisation called the Galm, who left hundreds of subterranean power nodes in the wake of their mysterious disappearance from the planet. Harnessing the power of the nodes and using them to sustain their cities, the human settlers grew too rapidly and drew too much power, and so for a night they unwittingly unleashed the Lights. All those who look upon the Lights are changed in frightening ways, and a devastating catatrophe occurs within the city of Eul. The story of this novella comprises of four chapters, each following a different struggle at different stages of the event of the Lights. First comes the sergeant, leading an extermination squad in the final days of the cataclysm. Then the merchant, who faces the chaos that ensues on the day following the appearance of the Lights. After that, the xenologist, an alien expert who is delving into the mysteries of the Galm inside the node itself. Finally, the zealot; a leader of a cult that worships the Lights as divine, and wishes only to recreate the Lights.

In the throes of World War II, two brothers enlist in the Royal Airforce''s Bomber Command. As the war intensifies, they soar into the perilous skies, leaving behind their families and loved ones. This harrowing yet heartfelt novel captures the bravery, sacrifice, and deep bond between these young men as they face unimaginable dangers on raids over Nazi occupied Europe. As the brother''s fates are sealed in the unforgiving theatre of war, their loved ones are left to grapple with the heartbreak of loss and the devastating cost of duty. From Above is not only a tribute to the courage of the few who fought in the skies, but also a poignant exploration of the far-reaching shadows cast by war. With rich historical detail and emotional depth, this true story of brotherhood, love, and loss will resonate with readers long after the final page is turned.

Available in August 2022, Electrical Principles8e has been revised to underpin the UEE30820 Certificate III in Electrotechnology Electrician qualification. Written to AQFlevel 3, this edition has been strengthened to align to the newunits of competency, and further address new emerging technologies. Additional chapters make the text also usable for UEE22020 Certificate II in Electrotechnology (Career Start),broadening the appeal and giving students the opportunity to carry the same text through two qualifications.

Electrical Principles 8e has been revised to underpin the UEE30820 Certificate III in Electrotechnology Electrician qualification. Written to AQF level 3, this edition has been strengthened to align to the new units of competency, and further address new emerging technologies. Additional chapters make the text also usable for UEE22020 Certificate II in Electrotechnology (Career Start), broadening the appeal and giving students the opportunity to carry the same text through two qualifications.

URGENT Questions: Amid the continuing political strife, social violence, media deceit, and a world-wide pandemic, is "UNDERSTANDING" important to you? Are you dealing with deep heart hungers? Is there HOPE without FEAR? God and who He has revealed Himself to be in the Bible is THE PLACE to start. Preceptive illustrations by these pictures (with "His Word" printed for the illustration, lesson, and precepts) will address your hungers for truth, love, forgiveness, and justice. Throughout The Old and The New Testaments the Bible reveals God''s personal interest in your life struggles. Through THE HOLY SPIRIT''s tutorial guidance and revealing truth, "preceptive understanding" is available.Based on a picture Bible called Preceptive Illustrations of the Bible by Thomas Varty, which dates back to the late 1700''s, these pictures form the core of this beautiful and enriching book.Johnny Harper was one of the Founding members of the Museum of The Bible in Washington, D C. He is known for his large collection of Bibles and for his extensive knowledge on this subject. From his large collection of 14th through 17th century Bibles, he selected the images from this book as the most beautiful and illustrative images to tell the story of the Bible.

Danny's life was going well. He had a steady job and plans to buy his own place. That was until some rogue junk mail decided he needed a change of scenery.Now Danny's got a new start in another world and he needs to make sure he doesn't squander this opportunity at making the most of this new life.(Updated on March 12th, 2018: Story has been proofread.)

This book offers a fresh perspective on the fundamentals of programming languages through the use of type theory.

UN CLÁSICO INTERNACIONALMENTE ACLAMADO CON MÁS DE 2 MILLONES DE EJEMPLARES VENDIDOS Si está usted dispuesto a ser sincero y riguroso consigo mismo para llevar a cabo un profundo autoanálisis de sus pensamientos y de sus emociones, este libro puede ser el más importante que jamás haya leído. Pues, aunque no promete milagros, le puede ayudar más que todos los eufóricos libros de autoayuda juntos. La Terapia Racional Emotivo-Conductual (TREC) le enseñará a identificar los principales problemas emocionales que solemos padecer las personas. Pero, ¿qué podemos hacer para dejar de fustigarnos a nosotros mismos con Creencias Irracionales y fortalecer nuestro mundo emocional? La respuesta nos la ofrecen los autores que nos muestran qué hacer para cambiar las emociones y los pensamientos que nos hacen sufrir por otros que nos harán ser felices en cualquier situación. Lo importante no es la situación sino lo que yo percibo de la situación, es decir, mis pensamientos y mis emociones. Aquí encontrará métodos prácticos y probados para cambiar las emociones y las conductas con las que usted se perjudica a sí mismo. Métodos que son un reflejo de la dilatada experiencia de los autores como terapeutas y profesores de terapeutas de todo el mundo, y que han sido respaldados por centenares de estudios e investigaciones. «Éste es un libro que se ha convertido en una referencia obligada y que, muy probablemente, seguirá siéndolo durante los años venideros. Sin lugar a dudas, esta nueva edición va a resultar especialmente valiosa para los lectores de hoy en día, que tienen que afrontar retos sin precedentes en su vida diaria.» Melvin Powers, editor de Wilshire Book Company

Abstract: "Algorithms in Computational Geometry and Computer Aided Design are often developed for the Real RAM model of computation, which assumes exactness of all the input arguments and operations. In practice, however, the exactness imposes tremendous limitations on the algorithms -- even the basic operations become uncomputable, or prohibitively slow. When the computations of interest are limited to determining the sign of polynomial expressions over floating point numbers, faster approaches are available. One can evaluate the polynomial in floating point first, together with some estimate of the rounding error, and fall back to exact arithmetic only if this error is too big to determine the sign reliably. A particularly efficient variation on this approach has been used by Shewchuk in his robust implementations of Orient and InSphere geometric predicates. We extend Shewchuk's method to arbitrary polynomial expressions. The expressions are given as programs in a suitable source language featuring basic arithmetic operations of addition, subtraction, multiplication and squaring, which are to be perceived by the programmer as exact. The source language also allows for anonymous functions, and thus enables the common functional programming technique of staging. The method is presented formally through several judgments that govern the compilation of the source expression into target code, which is then easily transformed into SML or, in case of single-stage expressions, into C."

Abstract: "Decidability of definitional equality and conversion of terms into canonical form play a central role in the meta-theory of a type-theoretic logical framework. Most studies of definitional equality are based on a confluent, strongly-normalizing notion of reduction. Coquand has considered a different approach, directly proving the correctness of a practical equivalence algorithm based on the shape of terms. Neither approach appears to scale well to richer languages with unit types or subtyping, and neither directly addresses the problem of conversion to canonical form. In this paper we present a new, type-directed equivalence algorithm for the LF type theory that overcomes the weaknesses of previous approaches. The algorithm is practical, scales to more expressive languages, and yields a new notion of canonical form sufficient for adequate encodings of logical systems. The algorithm is proved complete by a Kripke-style logical relations argument similar to that suggested by Coquand. Crucially, both the algorithm itself and the logical relations rely only on the shapes of types, ignoring dependencies on terms."

This street atlas of London contains a large amount of detail, with land use clearly colour coded to aid use. It includes thousands of updates and has involved extensive and exhaustive research on the ground. It incorporates mapping at four different scales, ranging from route planning maps to large-scale central area maps.

Abstract: "We study the typing properties of closure conversion for simply-typed and polymorphic [lambda]-calculi. Unlike most accounts of closure conversion, which only treat the untyped [lambda]-calculus, we translate well-typed source programs to well-typed target programs. This allows later compiler phases to take advantage of types for representation analysis and tag-free garbage collection, and it facilitates correctness proofs. Our account of closure conversion for the simply-typed language takes advantage of a simple model of objects by mapping closures to existentials. Closure conversion for the polymorphic language requires additional type machinery, namely translucency in the style of Harper and Lillibridge''s module calculus, to express the type of a closure."

Abstract: "There is a middle ground between parametric and ad-hoc polymorphism in which a computation can depend upon a type parameter but is restricted to being defined at all types in an inductive fashion. We call such polymorphism non-parametric. We show how non-parametric polymorphism can be used to implement a variety of useful language mechanisms including overloading, unboxed data representations in the presence of ML-style polymorphism, and canonical representations of equivalent types. We show that, by using a second-order, explicitly typed language extended with non-parametric operations, these mechanisms can be implemented without having to tag data with type information at run-time. Furthermore, this approach retains a 'phase distinction' and permits static type checking and separate compilation. Our aim is to provide a unifying language, translation, and proof framework in which a variety of non- parametric mechanisms can be expressed and verified."

By abstracting away from the specifics of the SML/NJ compiler, the IRM readily generalizes to arbitrary ''compilation tools'' such as parser generators and embedded languages."

Abstract: "A proof of the soundness of Tofte''s imperative type discipline with respect to a structured operational semantics is given. The presentation is based on a semantic formalism that combines the benefits of the approaches considered by Wright and Felleisen, and by Tofte, leading to a particularly simple proof of soundness of Tofte''s type discipline."

Abstract: "We describe a module system for Elf, a logic programming language based on the LF logical framework. The static part of module calculus addresses name-space management and structured presentation of deductive systems. The dynamic part addresses search-space management and modularization of logic programs."

To address this question, Cardelli and Mitchell suggest an extension to their subsumption-based calculus to admit mergeability constrains [sic]. In this paper we show that a subsumption-free calculus based only on mergeability constraints suffices not only for symmetric merge, but also for a wide class of other record operations. Moreover, the proposed calculus avoids some known difficulties with recursive types associated with positive-information calculi; in particular, the motivating examples for F-bounded quantification may be readily expressed without extending the language. A number of object oriented features, such as those considered by Wand and Buneman and Ohori, may also be represented naturally in this calculus."

Abstract: "Standard ML is a useful programming language with a polymorphic type system and a flexible module facility. One notable feature of the core expression language of ML is that it is implicitly typed: no explicit type information need be supplied by the programmer. In contrast, the module language of ML is explicitly typed; in particular, the types of parameters in parametric modules must be supplied by the programmer. We study the type structure of Standard ML by giving an explicitly-typed, polymorphic function calculus that captures many of the essential aspects of both the core and the module language.

Abstract: "The Logical Framework (LF) is a system for defining a wide class of logics. It is based on a general treatment of syntax, rules, and proofs in terms of a typed [lambda]-calculus with dependent types. Syntax is treated in a style similar to, but more general than, Martin-Löf's system of arities. The treatment of rules and proofs focuses on his notion of a judgement. Logics are encoded in the LF via a new principle, the judgements as types principle, whereby each judgement is identified with the type of its proofs. This allows for a smooth treatment of discharge and variable occurrence conditions and leads to a uniform treatment of rules and proofs whereby rules are viewed as proofs of higher-order judgements and proof checking is reduced to type checking. The practical benefit of our treatment of formal systems is that logic-independent tools such as proof editors and proof checkers can be constructed."

The Generalized Calculus of Constructions (CC[superscript [omega]]) is a formal theory of types that includes such a hierarchy of universes. Although essential to the formalization of constructive mathematics, universes are tedious to use in practice, for one is required to make specific choices of universe levels and to ensure that all choices are consistent. In this paper we study several problems associated with type checking in the presence of universes in the context of CC[superscript [omega]]. First, we consider the basic type checking and well-typedness problems for this calculus.

Following standard practice, we distinguish two types of logical system of open formulae that differ in the treatment of free variables, and show how they may be induced from a logical system of closed sentences. The technical notions of a logic presentation and a uniform encoding of a logical system in LF are generalized to the present setting."