bluuebunny/crossref_metadata_2025 huggingface dataset:
The Evolution of Behavioral Norms of Reaction as a Problem in Ecological Genetics: Theory, Methods, and Data
Authors: Carroll Scott P. , Corneli Patrice Showers
Published: November 2020

Behavior, like other phenotypic traits, varies as a function of genes and environment. Variation occurs at all demographic levels, within individuals over time, between individuals, and between populations and species. Whether variation is important will depend on the behavior and its context. For example, whether a bird scratches its head by extending a leg above or below the adjacent wing may not have profound fitness consequences, although species differences in this character may shed light on phylogenetic relationships (e.g., Wallace 1963; Simmons 1964). In contrast, other behaviors, such as the instantaneous decision to migrate or not, may affect fitness directly by altering the schedule of fecundity or mortality (Dingle et al. 1982). Such strategic behaviors (Maynard Smith 1982), which often depend for their expression on the assessment of local cues (Moran 1992), are complicated and important evolutionary traits. The phenotypic variability that defines them, however, has hindered our ability to treat them with formal evolutionary–genetic analyses that are central to the complete understanding of any putative adaptation. Much of the evolutionarily important variation observed in strategic behavior probably stems from differences among individuals due to genotype–environment interactions. To illustrate this in the most general terms, consider that behavioral distinctions among individuals may be based on (1) differences in the environmental conditions they experience, (2) differences in genetic elements that code for specific tactics or predispositions, or (3) differences in the genotype–environment interaction, manifested through developmental or facultative pathways, that is, “norms of reaction” (Schmalhausen 1949). Norms of reaction are functions that describe how a genotype is translated into a phenotype by the environment. They are becoming widely employed as a paradigm in evolutionary studies of physiological and life-history traits (e.g., Dingle 1992; reviewed by Stearns 1989), but are not yet used widely in studies of behavioral traits (but see Thompson this volume). Because much of the variation that behaviorists observe within populations and species is likely the result of a complex combination of individual differences in genetic code and differences in environment, norms of reaction need to be explored as a method for understanding the sources and structure of behavioral variation.
Effects of Relaxed Natural Selection on the Evolution of Behavior
Authors: Coss Richard G.
Published: November 2020

Theoretical discussion of the role of natural selection in shaping behavioral variation in different habitats has been an integral part of the study of animal behavior since the late 19th century. Herbert Spencer (1888) was among the first to argue that migrating populations that fail to adjust to environmental circumstances “are the first to disappear.” A common rationale for comparing populations or related species is the desire to identify behavioral differences that correspond with habitat properties providing different patterns of selection (Tuomi 1981, Riechert 1993, this volume). Behavioral similarities are often ignored or are treated as less interesting because the thrust of the research program emphasizes behavioral differences as an empirical test of the theory of natural selection. Nevertheless, these similarities can be as revealing of evolutionary process as are differences when they reflect behavioral convergence or slow disintegration of behavior under relaxed selection (Coss and Goldthwaite 1995). When populations invade novel habitats, they not only experience new selective regimes; they can also experience relaxed selection on specific behavioral phenotypes. This is particularly common when the new habitat is missing a class of predators that was abundant in the ancestral habitat (e.g., Curio 1975, Pressley 1981). Under relaxed selection, characters may disintegrate, presumably because mutations that result in loss of the phenotype are not at a selective disadvantage. Disintegration is not always observed, however. Instead, behavioral characters are sometimes retained for long periods of time after selection has been relaxed (Coss 1991b, Kaneshiro 1989). Inferring relaxed selection requires that the history of the contrasted populations be relatively well known. Both ancestral selective regimes and behavioral characters must be known if character polarity is to be established. Character polarity must be established to distinguish disintegration from parallel evolution of novel behavior patterns. This often is a problem in population contrasts because differentiation is usually too recent to have resulted in the evolution of enough derived characters for the use of standard cladistic methods of phylogenetic reconstruction, although recent advances in statistical and molecular techniques are promising (Foster 1994, Foster and Cameron 1996). Instead, inference of character polarity has typically relied on geological evidence and comparison with closely related species.
Variation in Advertisement Calls of Anurans across Zonal Interactions: The Evolution and Breakdown of Homogamy
Authors: Littlejohn Murray J.
Published: November 2020

The allopatric mode of speciation has become a dominant paradigm (sensu Kuhn 1970) in evolutionary biology over the last 50 years (Mayr 1942, 1992). In this model, the geographic range of a species is fragmented, the previously dedifferentiating effect of gene flow is interrupted, and the now separated populations diverge. If there is enough genetic differentiation during this period of isolation, then the disjunct daughter populations may become separate biological species (sensu Mayr 1942, 1992). This level of divergence is achieved by the development of sufficient genetic incompatibility, as reflected in an absolute infertility or sterility of hybrids or by sufficient reduction in the absolute or relative levels of adaptedness of hybrids so that none survives to maturity when in competition with parental individuals. Full and complete allopatric speciation, then, is marked by the acquisition of those properties needed for extensive and continuing coexistence. Broad overlap of geographic ranges (sympatry) can then develop without any significant interactions between individuals of the derived populations. In other situations, however, these essential properties may not have been acquired before the extrinsic barriers were removed. Thus, a critical stage is reached when the geographic ranges of previously separated daughter populations expand, and contact is established between individuals of the different genetic systems. Here the ecological compatibility, the specificity of mate choice, and the relative fitness of hybrids (if produced) are tested, and the following four outcomes may be envisaged. (1) If there is a cost to inbreeding, based on extrinsic and/or intrinsic factors, then the two lineages may diverge further in sympatry such that the attributes essential for stable coexistence arise, or are enhanced, through the direct action of natural selection within the context of the interaction (for references and recent commentaries, see Howard 1993, Littlejohn 1993, Butlin 1995). (2) If there is an ecological gradient and no cost to interbreeding because the hybrid progeny are as fit as, or fitter than, those of the parental taxa in part of the gradient, a geographically restricted and persistent hybrid zone may form (Moore 1977, Moore and Buchanan 1985, Littlejohn 1988, Hewitt 1989, Harrison 1993, Howard 1993).
Introduction
Authors: Crouch Dora P.
Published: November 2020

Cities are a constant interplay between tangible and intangible, visible and invisible factors. Long-lived cities can provide data to compensate for the brevity of our modern urban experience (Croce 1985). To overcome these gaps in research, just beginning to close, the city is a most useful unit of study. Ancient cities can serve as four-dimensional models (length, width, height, and time) of how humans survived in their ecological niches. Yet comparative studies of groups of cities—such as Rorig’s (1967) of German medieval trading cities of the Hanseatic League, Andrews’s (1975) of the urban design history of Maya cities, and Hohenberg and Lee’s (1985) of the economic history of European cities—ignore the geological setting. The setting of our study is the Mediterranean periphery where cities are united by their Greco-Roman historical and cultural relationships. From the twenty-five Greco-Roman sites studied in Water Management in Ancient Greek Cities, we have selected for further study 10 sites with sufficient geological information to form a basis of comparison. Our comparisons are based on the physical aspects—both form and function—of the local area, not the particular object. There are exciting possibilities, both intellectual and practical, in such an approach. Until recently, ancient Mediterranean cities have been investigated mainly by ancient historians and classical archaeologists. Cities, however, are so complex as to require every possible sort of investigation. Because each model and methodology leaves out too much, the use of a single model from one discipline, whether archaeological, mathematical, engineering, or historic, has limited usefulness. The documents of the classicists and the physical remains located by archaeologists seem to an urban historian like myself to be useful but incomplete sources that take for granted the geographical base, assume a past social organization, and may ignore the technological and scientific aspects of ancient urban life. As classicist M. H. Jameson (1990) has written, “The surviving literature from Classical Greece sheds light only incidentally on practical matters such as patterns of settlement and domestic architecture . . . [yet] conceptions drawn from literature, sometimes with dubious justification, continue to prevail.”
1983
Authors: Mack Maynard
Published: November 2020

I am reminded by Professor [Georges] May’s generous introduction of a story about Winston Churchill. After World War II and his stint as prime minister, he was invited back to his old school, Harrow, to give the commencement address and decided he ought probably to oblige. So he went, weathered an introduction almost as laudatory as the one you’ve just listened to (except in his case deserved) then got to his feet and said to the graduating class, “Nevah give up!” and sat down. I think you will agree that this is the most memorable commencement address you have ever heard as well as perhaps the wisest possible comment on the life that all of us here are engaged in fostering, and that I, alas, on grounds that will be no more apparent to you than they are to me, have been singled out (“fingered” is, I believe, the underworld term) to address: the life of learning. . . . Although I stand here before my betters, I do not stand here before very many of my elders. I have already drawn down from that mysterious fund with which we all begin three and a half years beyond my Biblical allowance, with the result that on any reasonably quiet afternoon I can hear my brain cells dying so fast they sound like popcorn. And that, I came to realize, is precisely what ACLS had in mind: they wanted to exhibit me, the way the Egyptians used to exhibit a skeleton at the beginning of their feasts. “Nothing like a mouldy old professor,” I could hear the Executive Board whispering, “to energize an audience of other professors into taking thought—before they get to be like him.” So do take thought, ladies and gentlemen, golden lads and girls; and as an old gravestone in Exeter churchyard says, “The faults you saw in me, Pray strive to shun; And look at home: There’s something to be done.” My instructions for this talk urged me to be somewhat personal, even to reminisce.
1992
Authors: Meinig D. W.
Published: November 2020

Had the idea of such an invitation ever crossed my mind, I would have thought the chances of being asked to give the Haskins Lecture as a good deal less likely than being struck by lightning. I found it a stunning experience, and I cannot be sure that I have recovered sufficiently to deliver a coherent response. I can only assume that I was selected because I am one of a rare species in the United States—an historical humanistic geographer—and someone must have suggested it might be of interest to have a look at such a creature, see how he might describe himself and hear how he got into such an obscure profession. Geographers are an endangered species in America, as, alas, attested by their status on this very campus [the University of Chicago], where one of the oldest and greatest graduate departments, founded ninety years ago, has been reduced to some sort of committee, and the few remaining geographers live out their lives without hope of local reproduction. I shall have more to say about this general situation, for while I have never personally felt endangered, no American geographer can work unaware of the losses of positions we suffered over many years and of the latent dangers of sudden raids from preying administrators who see us as awkward and vulnerable misfits who can be culled from the expensive herds of academics they try to manage. I have always been a geographer, but it took me a while to learn that one could make a living at it. My career began when I first looked out upon a wider world from a farmhouse on a hill overlooking a small town on the eastern edge of Washington State. My arrival on this earth at that particular place was the result of the convergence (this is a geographer’s explanation of such an event) of two quite common strands of American migration history. My paternal grandparents emigrated from a village in Saxony to Iowa in 1880, following the path of some kin.
1993
Authors: Schimmel Annemarie
Published: November 2020

Once upon a time there lived a little girl in Erfurt, a beautiful town in central Germany—a town that boasted a number of Gothic cathedrals and was a center of horticulture. The great medieval mystic Meister Eckhart had preached there; Luther had taken his vow to become a monk there and spent years in the Augustine monastery in its walls; and Goethe had met Napoleon in Erfurt, for the town’s distance from the centers of classical German literature, Weimar and Jena, was only a few hours by horseback or coach. The little girl loved reading and drawing but hated outdoor activities. As she was the only child, born rather late in her parents’ lives, they surrounded her with measureless love and care. Her father, hailing from central Germany, not far from the Erzgebirge, was an employee in the post and telegraph service; her mother, however, had grown up in the north not far from the Dutch border, daughter of a family with a centuries-long tradition of seafaring. The father was mild and gentle, and his love of mystical literature from all religions complemented the religious bent of the mother, grown up in the rigid tradition of northern German protestantism, but also endowed with strong psychic faculties as is not rare in people living close to the unpredictable ocean. To spend the summer vacations in grandmother’s village was wonderful: the stories of relatives who had performed dangerous voyages around Cape Horn or to India, of grandfather losing his frail clipper near Rio Grande del Sul after more than a hundred days of sailing with precious goods—all these stories were in the air. Mother’s younger sister was later to weave them into a novel and to capture the life in the coastal area in numerous radio plays. Both parents loved poetry, and the father used to read aloud German and, later, French classical literature to us on Sunday afternoons.
The Nightside Auroral Oval
Authors: Kennel Charles F.
Published: November 2020

The basic structure of the auroral oval was pieced together from relatively local magnetometer measurements and all-sky photographs taken on the ground. The all-sky cameras picked out relatively intense features whose intensities exceeded roughly one kilorayleigh. Their fields of view had a 500-1000 km radius at auroral altitudes, and so extended over 5-10 degrees of latitude and about 90 minutes of local time. Had the aurora been stationary and time-independent, this would have been enough, and it was enough to spot the existence of substorms. It was not enough to solve the substorm problem. As the instruments to study auroral phenomena grew in sophistication and comprehensiveness, so also did our understanding of the concept of the auroral oval. This chapter is dedicated to communicating some of this modern understanding as a prelude to the discussion of substorms in the next chapter. Ground instruments can follow the time development of events within their fields of view but have difficulty separating changes in space and time on scales longer than an hour of universal time or local time, because the observing station rotates with the earth to a local time sector where the aurora may differ. This difficulty can be offset to some extent by airplane flights that remain at a constant local time. However, the real breakthrough came with auroral imaging from space. In the 1970s, optical wavelength imaging from low-altitude polar orbit provided snapshots of the aurora over several thousand kilometer scale portions of the oval on each polar pass of the spacecraft (Shepherd et al., 1973; Anger et al., 1973; Lui and Anger, 1973; Pike and Whalen, 1974; Snyder and Akasofu, 1974). And the spacecraft could detect the precipitating particles responsible for the auroral light emitted from the magnetic footprint of the field lines along its path. The results from the first generation of auroral imaging experiments have been summarized in excellent reviews (Akasofu, 1974, 1976; Hultquist, 1974; Burch, 1979). Ultraviolet imaging allows one to see the dayside aurora.
The Role of GIS in the Interdisciplinary Investigations at Olorgesailie, Kenya, a Pleistocene Archaeological Locality
Authors: Potts Richard , Cole Daniel
Published: November 2020

A geographic information system is an ideal tool for use in interdisciplinary studies because it provides automated means of linking and relating different spatial databases. In this paper we discuss GIS applications to ongoing archaeological and paleoecological studies at Olorgesailie, an early hominid archaeological locality in the rift valley of southern Kenya and one of the most noted Acheulian handaxe sites worldwide (Isaac 1977). The questions being asked in early hominid archaeology require thinking beyond individual artifacts and site excavations to broader spatial scales within welldefined time intervals (or chronostratigraphic units) (Blumenschine and Masao 1991; Potts 1991). The sedimentary exposures at Olorgesailie permit the smallest spatial scale of individual artifacts and fossils to be integrated with regional-scale studies. Since many of the GIS applications are still in initial form, the purpose here is largely to illustrate the conceptual framework by which GIS integrates the analysis of spatial data at varying geographic scales in the Olorgesailie basin. Covering over 4000 km in length, the African Rift System trends southward from the Afar Triangle in the Red Sea region to south of the Zambezi River in Zambia. The numerous continental rift basins that make up the rift system have a complex structural and volcanic history. For most of its length, the African Rift traverses Ethiopia, Kenya, and Tanzania. The rift is divisible into eastern and western portions, which merge into a broad faulted region in northern Tanzania (Baker et al. 1972). Between the eastern and western rifts, occupying portions of Uganda, Tanzania, and northern Kenya, is an uplifted plateau 1000 to 1200 m in elevation. Uplifted, elongated domal structures located in Ethiopia and Kenya form the structural base from which the East African Rift System has developed. The rocks that make up this shield complex are Precambrian gneisses, quartzites, and schists. In addition to intrusions by dikes and plutons, these basement rocks have been altered by partial melting and metamorphism. Significant though episodic uplift of the Kenyan dome and its flanks during the late Cretaceous and middle and late Tertiary contributed to the development of a graben structure (Baker 1986; Baker et al. 1972).
Drug Delivery
Authors: Saltzman W. Mark
Published: November 2020

Synthetic materials are a tremendous potential resource for treating human disease. For the rational design of many of these biomaterials it is necessary to have an understanding of polymer chemistry and polymer physics. Equally important to those two fields is a quantitative understanding of the principles that govern rates of drug transport, reaction, and disappearance in physiological and pathological situations. This book is a synthesis of these principles, providing a working foundation for those in the field of drug delivery. It covers advanced drug delivery and contemporary biomaterials.
Introduction
Authors: Saltzman W. Mark
Published: November 2020

Humans have always attempted to improve their health by ingesting or administering drugs. Examples appear throughout written history, from every continent and culture. Noah produced alcohol [1] and Christ was offered a sedative to ease the pain of crucifixion [2]. The use of opium was described by Theophrastus in the third century B.C., the stimulating power of methylxanthines was exploited by ancient Arabian shepherds and priors, and the paralyzing properties of curare were recognized by native South Americans centuries before the arrival of Sir Walter Raleigh [3]. The chemotherapy of cancer, which many consider a modern development, has existed in some form for over 500 years [4]. Vaccination, the intentional exposure to pathogens, was used in China and India to prevent smallpox and other infections [5] centuries before the birth of either Jenner [6] or Pasteur [7]. Even during the 20th century, drug discovery frequently resulted from empiricism and happenstance. The anticancer effects of nitrogen mustard were realized during the development of chemical-warfare agents, and penicillin was discovered after the inadvertent contamination of a bacteriological plate. As technology advanced, particularly after 1970, methods of drug and vaccine production became more sophisticated and rational. In parallel with the rise of modern pharmaceutical technology and the explosive ascent of biotechnology, the cellular and molecular basis for the action of many drugs has been uncovered. Today, drug designers benefit from an accumulated base of scientific knowledge concerning, for example, the interactions between neurotransmitters and their receptors, the regulation of hormone secretion, and the sensitivity of tumor cells to specific kinds of chemicals. New technology and clearer biological insight have led to new classes of therapeutic and prophylactic agents. Consider some of the new products made available to patients in the United States over the last few years. A revolution in drug development is clearly upon us. Even more complex agents, such as chimeric antibodies, gene-based drugs, antisense oligonucleotides, and virus-like particles, are emerging as clinically viable entities. New clinical approaches involve cells as well as molecules; the introduction of genetically modified cells into humans has blurred the distinction between conventional pharmacology and transplantation.
Pharmacokinetics of Drug Distribution
Authors: Saltzman W. Mark
Published: November 2020

Pharmacology, the study of agents and their actions, can be divided into two branches. Pharmacodynamics is concerned with the effects of a drug on the body and, therefore, encompasses dose–response relationships as well as the molecular mechanisms of drug activity. Pharmacokinetics, on the other hand, is concerned with the effect of the body on the drug. Drug metabolism, transport, absorption, and elimination are components of pharmacokinetic analysis. Physiology influences the distribution of drugs within the body; overall distribution depends on rates of drug uptake, rates of distribution between tissue compartments, and rates of drug elimination or biotransformation. Each of these phenomena potentially involves aspects of drug diffusion, permeation through membranes, and fluid movement that were introduced in the previous sections. The goal of pharmacokinetics is synthesis of these isolated basic mechanisms into a functional unit; this goal is most often achieved by development of a mathematical model that incorporates descriptions of the uptake, distribution, and elimination of a drug in humans or animals. This model can then be used to predict the outcome of different dosage regimens on the time course of drug concentrations in tissues. The development of a complete pharmacokinetic model for any given drug is a substantial undertaking, since the fate of any compound introduced into a whole organism is influenced by a variety of factors, and is usually complicated—in ways that are difficult to predict—by the presence of disease. In this section, pharamacokinetics will be introduced by first considering the simplest situation: an agent is introduced into a single body compartment from which it is also eliminated. While quite sophisticated compartmental models can be developed from this basic construct, it is frequently difficult to relate model parameters (such as the volume of specific compartments or the rate of transfer between compartments) to physiological or anatomical parameters. To avoid this difficulty, physiological pharmacokinetic models are frequently employed; in these models, the kinetics of drug uptake, distribution, and elimination from local tissue sites are predicted by constructing anatomically and biochemically accurate models of the tissue environment.
Drug Modification
Authors: Saltzman W. Mark
Published: November 2020

Previous chapters present the characteristics of drug movement through the body. Diffusion is an essential mode of transport at the microscopic scale; concentration gradients drive a substantial fraction of the molecular movements within cells and the extracellular space. The confinement and regulated passage of molecules within compartments of a tissue or cell is also essential for function; membranes confine molecules to spatial locations and regulate transport between these isolated spaces (Chapter 5). Membranes frequently are the major obstacles to the entry or distribution of therapeutic compounds (Chapter 7). Therefore, much of the effort in drug design and drug delivery is devoted to overcoming these diffusional or membrane barriers. This chapter describes strategies for manipulating agents in order to increase their biological activity. The sections orbit a central assumption: i.e., agents can be modified to make analogous agents (analogs), which are chemically distinct from the original compound, but produce a similar biological effect. Nature uses a similar strategy, called “biotransformation” to assure elimination of many toxic compounds and drugs. Substantial chemical modification is often needed in order to impact physical properties that influence drug distribution such as stability or solubility; the challenge of drug modification is to identify chemical features that can be changed without sacrificing biological activity. Often, our understanding of the relationship between chemical structure and biological function for an agent is incomplete, making the rational production of analogs difficult. Drug modifications are frequently directed at altering properties that influence the concentration of the compound (i.e., its solubility), the duration of action (which is usually related to its stability in tissue), or the ability of drug molecules to move between compartments in tissues (which is often related to its permeability in membranes). A chemical modification can effect multiple properties, so these divisions are frequently not as distinct as the section headings suggest. Many agents are protected from degradation within tissues by binding. Binding provides a mechanism for sequestering an unstable or potent compound within a region of a tissue. Protective binding occurs frequently within the plasma and extracellular matrix (ECM); the complex molecular composition of these tissues provides many potential binding sites.
Parallel Models of Computation
Authors: Greenlaw Raymond , Hoover H. James , Ruzzo Walter L.
Published: November 2020

Before we can discuss the difficulty of solving a problem, we must first choose a suitable machine model in which to describe our computations. A machine model is a parameterized description of a class of machines. Each machine in the class is obtained from the model by giving specific values for the parameters. For example, a Turing machine is specified by giving the number of work tapes, symbol set, and program. The choice of model that we make depends on how we wish to balance such factors as simplicity, generality, historical use, novelty, plausibility of actual implementation, and ease of programming. This flexibility inevitably leads to a proliferation of different models, and parallel computation is no exception to this tendency toward diversity. The menagerie of parallel models includes bit vector machines (Pratt and Stockmeyer [293]), Boolean circuits (Borodin [40]), parallel random access machines, or PRAMs (Fortune and Wyllie [109], Goldschlager [126]), k-PRAMs (Savitch and Stimson [323]), alternating Turing machines (Chandra, Kozen, and Stockmeyer [49]), parallel pointer machines (Cook and Dymond [68], Dymond [98], Dymond and Cook [99, 100]), aggregates ([98, 99, 100]), conglomerates (Goldschlager [126]), and a large variety of machines based on fixed interconnection networks, such as grids, hypercubes, and shuffle-exchange (see Leighton [228]). Such variety makes it difficult to compare competing models. At the qualitative level, models can be distinguished by their processor granularity and their interconnection pattern. One important distinction among models is in the granularity with which they treat parallel operations. A model can be fine-grained and treat bit operations as the basic unit of parallel computation, or it can be coarsegrained and, for example, treat local sub computations on processors as the fundamental unit. In addition the model can be structured, in which case the machine can only manipulate atomic data objects and cannot access their representations (as bits for example). Another important qualitative difference among models is the nature of the communications between processing elements. Some models allow unrestricted communication between processing elements at any time. Other models require a fixed communication pattern. In some models there is no charge for the communication pathway between elements, in others there is.
Two Other Notions of P- Completeness
Authors: Greenlaw Raymond , Hoover H. James , Ruzzo Walter L.
Published: November 2020

The usual conventions of algorithm analysis express the complexity of finding a solution in terms of the length of the problem input. This will generally make the complexity sensitive to the encoding scheme used to describe problem instances. As an extreme example, the complexity of factoring a positive integer encoded in binary is quite different from that of factoring a number encoded in unary, or encoded as a product of prime factors. Realistic complexity analysis assumes that the encoding conventions for a problem are reasonable, that is, they do not make it trivial to do something for which there is evidence of difficulty (see Section 3.2). This sensitivity to encodings is particularly significant for number problems. In such problems, the numerical values of the parameters of a problem instance are much larger than the size of the problem description. For example, a description of size O(n3) can represent a network of n vertices and n2 edges, with edge capacities of size O(2n). Thus, the flows in the network described by problem instance I can be exponentially larger than the size of I. The following definition captures this concept. Definition 9.1.1 For any instance I of a problem, let Max(I) denote the maximum magnitude of all numbers in I. For any encoding scheme for the problem, let \I\ denote the length of the encoding of the instance. A problem is a number problem if and only if there exists an encoding scheme for the problem such that there does not exist a polynomial p such that for any instance I, Max(I) ≤ p(|I|). A typical characteristic of a number problem is that when binary encodings of parameters in an instance I are replaced with unary encodings, the size of the encoding increases exponentially. Often, the unary encoded version is large enough to permit the problem to be solved efficiently in terms of the input length.
Risk Analysis Of Petroleum Prospects
Authors: Harbaugh John W. , Wendebourg Johannes
Published: November 2020

Risk analysis of an oil or gas prospect requires a probability distribution with two components, a dry-hole probability plus a distribution of oil or gas volumes if there is a discovery. While these components should be estimated objectively, risk analysis as currently practiced is mostly guesswork. Geologists assign outcome probabilities without appropriate procedures or data for objective estimation. Valid estimates require frequency data on regional exploratory drilling-success ratios, frequency distributions of oil and gas field volumes, and systematic tabulations of geological variables on a prospect-by-prospect basis. Discriminant functions can be used to analyze relationships between geological variables and hydrocarbons, leading to outcome probabilities conditional on discriminant scores. These probabilities can be incorporated in risk-analysis tables to yield risk-weighted financial forecasts. Computers are required for all procedures. Prior to drilling a petroleum prospect, the likelihood of good outcomes must be weighed against the bad to obtain a risked financial estimate that combines all possibilities. Some oil operators simply contrast the value of discovery that is expected, versus the cost of a dry hole. A cashflow projection yields an estimate of the revenue that will be received if a discovery is made. This assumes an initial producing rate and an ultimate cumulative production for the operator's net revenue interest, and an oil price. When the stream of revenue is discounted and costs for the lease, the completed well, and operating expenses and taxes are subtracted, the net present value is obtained. If the hole is dry, its cost is readily estimated. Only two monetary estimates coupled with an intuitive guess about the likelihood of a producer versus a dry hole form the basis for a decision. A great deal of oil has been found by both independent operators and major oil companies using such simple decision systems. Oil companies generally use more advanced methods at present. Many require their geologists to supply probability estimates for a spectrum of outcomes for each individual prospect, ranging from the probability of a dry hole through the probability of a small discovery, a medium-sized discovery, and various magnitudes of large discoveries.
Information Management And Mapping System For Subsurface Stratigraphic Analysis
Authors: Gill D. , Levinger M.
Published: November 2020

An information management and mapping system combining a series of interactive computer programs for stratigraphic, lithofacies, paleogeographic, and structural analysis interfaced with a comprehensive database on subsurface geology produces contour maps of quantitative variables including structure maps, isopach maps, and maps of lithofacies parameters; detailed lithologic and stratigraphic logs; and printouts of lithofacies parameters for all levels of the lithostratigraphic subdivision. Users communicate by means of simple, on-screen, menu-driven dialogues controlled by FORTRAN programs. The system runs on DEC/Micro VAX II computers operating under VMS. This information management and mapping system for subsurface stratigraphic analysis is an integration of a comprehensive database on the subsurface geology of Israel and a series of computer programs for stratigraphic, lithofacies, paleogeographic, and structural analysis. Development of the system, referred to as "ATLAS -RELIANT," was sponsored by OEIL [Israel Oil Exploration (Investment) Ltd.). The system serves primarily as a storage and retrieval facility for information on the subsurface geology of Israel. Users can obtain printouts of lithologic and stratigraphic logs, contour maps, and value maps. The system originally was developed to run on a CDC machine under the NOS/BE operating system. Later OEIL expanded the database to include many additional items of information [inventory of cores and petrophysical logs, results of production tests, results of petrophysical analyses, geochemical analyses of recovered fluids (water samples and hydrocarbons), and results of quantitative analyses of petrophysical logs] and the system was modified to run on DEC/Micro VAX II computers under the VMS operating system (Shertok, 1969). Among other things, the ATLAS-RELIANT system was instrumental in the regional stratigraphic analysis of the subsurface geology of Israel performed by OEIL during 1968-1988 (OEIL, 1966; Cohen et al., 1990). The database, dubbed "ATLAS," is about 16 MB in size and contains information on 320 petroleum exploration and development boreholes, 50 deep water wells, and 100 columnar sections of outcrops.
A worked example
Authors: Schenck Douglas , Wilson Peter
Published: November 2020

In this Chapter we provide a complete worked example of the development of an information model. The initial model specification is taken from an ISO report, TR 9007, which, among other things, describes several means of representing this particular example. The model representations used here are the EXPRESS-G and EXPRESS languages, and this also serves as an introduction to some aspects of the languages. Minor use is also made of EXPRESS-I. For explanatory purposes we do not strictly adhere to the methodology described earlier. The principal difference being that we develop simultaneously both a graphical and a lexical version of the model. The initial model statement for the worked example is given in Section 4.1.1 and 4.1.2 and is taken from ISO TR 9007. In our modeling methodology this would be developed by the modeling team as the initial step in the modeling process. By the time the team is in a position to be as clear on the specification as given in 4.1.2 about the real world aspects of the problem, then the majority of the modeling work has been accomplished. The remaining task, which is what we will be concentrating on, is to formally describe and document the model. The scope of the model to be described has to do with the registration of cars and is limited to the scope of interest of the Registration Authority. The Registration Authority exists for the purpose of: • Knowing who is or was the registered owner of a car at any time from construction to destruction of the car. • To monitor certain laws, for example regarding fuel consumption of cars and their transfer of ownership. There are a number of manufacturers, each with one unique name. Manufacturers may start operation, with the permission of the Registration Authority (which permission cannot be withdrawn). No more than five manufacturers may be in operation at any time. A manufacturer may cease to operate provided he owns no cars, in which case permission to operate lapses. A car is of a particular model and is given a serial number by its manufacturer that is unique among the cars made by that manufacturer.
Datatypes
Authors: Schenck Douglas , Wilson Peter
Published: November 2020

This chapter explains the EXPRESS pseudotypes and datatypes. You will also want to read about defined types and entity types, both of which are covered in Chapter 11. Datatypes represent domains of values. A domain is the set of possible values associated with an attribute, local variable or formal parameter. Datatype values can be operated upon as explained in Chapter 14. EXPRESS is fussy about the way datatypes are used. The datatypes are grouped this way: • Pseudo (Generic and Aggregate — see 10.1) • Simple (Integer, String, etc. — see 10.2) • Collection (Array, List, etc. — see 10.3) • Enumeration and Select (see 10.4 and 10.5). • Named (entities and defined types — Chapter 11) Then, the context in which a reference to a datatype is made will be • as the type of an attribute, • as the type of a local variable, • as the type of a formal parameter, or • as the underlying type of a defined type. At last, a summary of the datatypes that can be used in the different contexts is given in Table 10.1. Notice that pseudotypes can only be used as formal parameter types and, the enumeration and select types can only be used as the underlying types of defined types. Pseudotypes are used only as the types of the formal parameters of functions and procedures. They can be regarded as templates into which various specific types can be placed. See 11.5.1 for more about formal parameters. The domain of a generic pseudotype is every conceivable value. When a procedure or function that has a generic type parameter is invoked it will accept any kind of actual parameter. No questions asked! Functions or procedures that use formal parameters typed as generic must be prepared to deal with whatever actual stuff is tossed its way and any operations performed on them will depend on the specific type of the actual parameter. Generic parameters should never be used when a more specific type can be used instead. In any event, the mechanics involved in writing an algorithm that is capable of handling every possible input value are tricky. The message is: Don’t use generic parameters unless you simply have to.
Declarations
Authors: Schenck Douglas , Wilson Peter
Published: November 2020

This Chapter explains the objects that you create to represent information of interest to you. The purpose of EXPRESS, and the information modeling process in general, centers on these declarations. The main object you declare is a schema. Within a schema you might declare constants, types, entities, functions, procedures and rules. Within those things are sub-objects such as attributes, local variables and parameters. The structure of EXPRESS source defines the scope of declarations. The statements Schema.. .End_Schema mark the boundaries for a group of declarations. In a like manner an entity or function declaration bounds the declarations made within them and so forth. This process of declaring things inside other things indicates the way one declaration ‘owns’ other things. In the case of an entity declaration, the attributes and local rules represent the properties that define it. So, an attribute is owned by a particular entity and also is a property of it. The rule is an exception to the way the structure of the source shows ownership and property definition. Rules are structurally subordinate to a schema, but they are logically subordinate to the entities to which they apply. Unlike an attribute that is owned by exactly one entity, a rule can be owned by more than one of them and conversely, a rule can be a property of several entities. This exception to an otherwise orderly correlation between the source structure and the way ownership and property definition is shown is a potential cause of confusion. Keep this special situation in mind as you build information models with EXPRESS. Exercise 11.1 Why do you think the authors of EXPRESS treated the rule differently? A schema declaration surrounds every other thing you declare. Therefore, SCHEMA YourSchemaName; END_SCHEMA; is the smallest possible EXPRESS legal source. Normally, however, a schema declaration contains declarations of constants, entities, functions, procedures, rules and types. A schema defines a collection of objects that have a related meaning and purpose. For example, geometry might be the name of a schema that collects declarations of points, curves, surfaces and other related objects. The order in which objects are declared is never relevant to the meaning of a schema as a whole or to the individual things declared in it.
References
Authors: Schenck Douglas , Wilson Peter
Published: November 2020

Identifiers (or names) are created by a declaration. They are referenced by various statements. EXPRESS does not require declaration before reference, therefore the reference can come after or before the place where the declaration is given. The usual way of referring to a thing is to simply write its name. However, there are situations where a more elaborate reference — called a qualified reference — is needed. Some qualified names can be quite long. The Alias statement (13.2) can be used to simplify matters when the qualified name gets too clumsy to work with conveniently. A scope is a region of the source within which a name is visible. References to a name are legal in its scope but are illegal outside it. Scopes can be thought of as boxes nested within other boxes as illustrated by Figure 12.1. EXPRESS assumes that there is a giant box called the ‘universe’ which surrounds every other scope. All of the standard identifiers (Integer, Real... Abs, Usedln...) and all schemas are in the scope of the universe. As an example Figure 12.2 gives an inventory of the full names of the things shown in Figure 12.1 (but note that ‘universe’ is never specifically written). Although it may seem that some of the ‘given’ names are duplicates (AnAttribute for instance), when the full name is written out every name is unique. Name uniqueness is a requirement of EXPRESS. Peer names are visible to one another. The picture shows peer names as the ones inside the same box. The same effect is shown in the inventory by tracing common name elements from left to right until a name difference is found. Peer names are the ones at the level where the difference occurs. Visibility to other names starts at some point in the name chain. Every name along the path (reading from right to left) and their peers are visible. In the picture, start inside some box and jump outside. The names in that outer box are visible. Then jump to the next outer box, etc., until there are no more outer boxes. As an example, ASchema. AnotherEntity. AnotherAttribute (‘Universe’ will no longer be used) can ‘see’ the things shown in Figure 12.3. In fact, references can to their simple names can be used.