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The United States mining industry has made steady progress to improve worker safety and reduce injuries. Despite these gains, the industry remains largely reactive in its approach to health and safety. There remains a primary focus on lagging indicators, such as the numbers of injuries, hours lost, and hazards found at the worksite. To facilitate a more proactive approach, new methods are needed to evaluate hazardous conditions and unsafe behaviors. This work explores the relationships among mine workers’ hazard recognition abilities, the individual’s perception of risk, and the safety culture of the mining workplace. We have conducted a literature review to identify key factors and analytical models in industries where health and safety are a major consideration, including construction, manufacturing, mining, and transportation. Our analysis considered both process-oriented frameworks, such as Systems Thinking approaches, and statistical methods, including Structural Equation Modeling (SEM). A meta-model was then developed to aggregate and examine key factors and potential causal relationships. We discuss the creation of this meta-model, identifying notable structural characteristics and hypotheses for future confirmatory analysis. Use cases are then outlined, including descriptive, evaluative, and generative applications.

To predict NFL game outcomes, we examine the application of technical stock market techniques to sentiment gathered from social media. From our analysis we found a $14.84 average return per sentiment-based wager compared to a $12.21 average return loss on the entire 256 games of the 20152016 regular season if using an odds-only approach. We further noted that wagers on underdogs (i.e., the less favored teams) that exhibit a golden cross pattern in sentiment (e.g., the most recent sentiment signal crosses the longer baseline sentiment), netted a $48.18 return per wager on 41 wagers. These results show promise of cross-domain research and we believe that applying stock market techniques to sports wagering may open an entire new research area. Gathered NFL tweet sentiment to predict outcomes and wagering decisionsUsed difference in moving averages for optimal wagering return ($14.84/game)Sentiment exhibiting a golden cross netted $48.18/game returnsFans were able to signal winning teams by their change in sentiment.

In this paper, a stochastic dynamic programming (SDP) based optimization model is formulated for the equipment replacement optimization (ERO) problem that can explicitly account for the uncertainty in vehicle utilization. The Bellman approach is developed and implemented to solving the ERO SDP problem. Particular attention is paid to the SDP state-space growth and special scenario reduction techniques are developed to resolve the “curse of dimensionality” issue that is inherent to the dynamic programming method to ensure that the computer memory and solution computational time required will not increase exponentially with the increase in time horizon. SDP software computer implementation techniques, functionalities and the Graphical User Interfaces (GUI) are discussed. The developed SDP-based ERO software is tested and validated using the current Texas Department of Transportation (TxDOT) vehicle fleet data. Comprehensive numerical results, such as statistical analyses, the software computational time and solution quality, are described and substantial cost-savings have been estimated by using this ERO software. Finally, future research directions are also suggested.

Aims to conduct an exploratory study on the organisational implications of strategic alignment within the steel stockholder supply chain by analysing the responses of a case study organisation. Increasingly fragmented and volatile markets result in pressure on organisations to strategically align all aspects of their supply chain to ensure rapid and appropriate responsiveness. There is a paucity of research in this area in the steel stockholder supply chain. A strategic alignment model was selected which incorporated alignment from four key aspects, namely markets, strategy, culture and leadership style. The model is used as an analysis framework for a case study in the steel stockholder supply chain. Data collection included a survey of a stratified sample of customers, company archive and organisational material and semi‐structured interviews. The implications for the supply chain and the organisation’s response are discussed and evaluated.

In preparation for new satellite sensors, such as VEGETATION on SPOT-4 and the MODerate Resolution Imaging Spectrometer (MODIS), we investigate the potential of the shortwave infrared (SWIR) signal to improve Leaf Area Index (LAI) retrieval in the boreal forests of Canada. Our study demonstrates that an empirical SWIR modification to the simple ratio (SR) vegetation index, termed the reduced simple ratio (RSR), has the potential to unify deciduous and conifer species in LAI retrieval, shows increased sensitivity to LAI, and demonstrates an improved correlation with LAI in individual jack pine and black spruce canopies. The unification of deciduous and conifer species suggests the possibility of not requiring a cover type stratification prior to retrieving LAI information from remotely sensed data, and has impact where no cover type information will be made or where the mix of cover types within a pixel is unknown. We use a geometric–optical canopy reflectance model to quantify the potential variation in jack pine and black spruce canopy reflectance caused by differences in background reflectance. The modeling study supports the results from the image analysis of the RSR showing increased sensitivity to LAI and reducing background effects in these conifer canopies.

As in conventional database management systems (DBMSs), to allow users to efficiently access and retrieve data objects, a multimedia database management system (MMDBMS) must employ an effective access method such as indexing and hashing. This paper provides a survey of tree-based multidimensional indexing techniques for MMDBMSs that maintain image data represented as feature vectors. These techniques support such data while maintaining desirable characteristics of a B-tree, an index structure most commonly used in traditional DBMSs. In this survey, we provide descriptions of each tree as well as give examples of the different data organization schemes. We also describe the advantages and disadvantages of using each technique. In addition, we provide classifications of the trees using several different properties. These classifications should assist researchers in identifying the strengths and weaknesses of any new indexing technique they develop as well as help users determine the most appropriate data structure for their applications.

This article explores immersive virtual reality as a potential educational strategy for nursing education and describes an immersive learning experience now being developed for nurses. This pioneering project is a virtual reality application targeting speed and accuracy of nurse response in emergency situations requiring cardiopulmonary resuscitation. Other potential uses and implications for the development of virtual reality learning programs are discussed.

In order to improve the robustness of systems that perform similarity searching, it may be necessary to augment a collection of images in a Multimedia DataBase Management System (MMDBMS) with an additional set of edited images. Previous research has demonstrated that space can be saved in such a system by storing the edited images as sequences of editing operations instead of as large binary objects. The existing approaches for performing similarity searching in an MMDBMS, however, typically assume that the data objects are stored as binary objects. This paper proposes algorithms for performing colour-based similarity searches of images stored as editing operations and provides a performance evaluation illustrating their respective strengths and weaknesses.

Many current multimedia database management systems perform content-based retrieval of images by extracting the values of various features from every object stored in their system. This can be time-consuming, especially if extracting the features requires a human to analyze each object. This process can be minimized in multimedia database systems that store images as a sequence of editing operations, called specifications, instead of the usual binary format. This paper discusses the advantages and applicability of such systems and the issues that must be resolved in order to develop them.

A local stability analysis is given for both the analytic and numerical solutions of the initial value problem for a system of ordinary differential equations. The standard linear stability analysis is reviewed, then it is shown that, using a proper choice of Liapunov function, a connected region of stable initial values of both the analytic solution and of the one-leg k-step numerical solution can be approximated computationally. Correspondence between the one-leg k-step solution and its associated linear k-step solution is shown, and two examples are given.

The role of the dissertation as part of academic preparation is generally accepted and unquestioned. The dissertation is intended to initiate students into serious research in their chosen field. However, what happens to the research, once completed, is another question. Apparently very few have addressed this question, and their findings are not consistent. McPhie, in a study of dissertations completed in social studies education, measured the dissemination of dissertations via library circulation. He concluded that: “These data on library circulation, even when viewed with caution, would seem to indicate a rather meager use of some potentially valuable findings.” He also found that nearly two-thirds had not published even one article from their dissertations. In a more recent study of Ph.D. dissertations in sociology, Yoels found a similar picture. He concluded, after analyzing citations to Ph.D. dissertations in the two most frequently cited journals in sociology, that “the likelihood that dissertations will be widely disseminated appears to be slim.” However, in a recent and more complete study, Hanson found that dissertations are more widely used than is indicated in the above studies. He concludes that: “When one broadens the definition of dissemination to include the media of books, monographs, chapters, presented papers, journal articles (including those not appearing in the two major journals), research bulletins, and miscellaneous forms during the professional life of the Ph.D. sociologist, a picture of more extensive transmission of dissertation results emerge. A conservative estimate would be that findings from a substantial majority of dissertations are disseminated through various media at some point in time.”

The decomposition of a block tridiagonal matrix into the product of block lowe and upper matrices is described. The cost of solving a block tridiagonal system of equations is given and compared to profile gaussian elimination. The desirability of a less expensive method is coupled to physical intuition about a common problem of solving a slowly varying sequence of such systems to motivate an iterative method based on residual correction. The method is described and convergence criteria are derived. An expression of the cost is developed and is shown to compare favourably with decomposition in many cases. Problems and advantages in computer implementation of the method are discussed and results of tests of a particular implementation on a well-known problem are given.

A local stability analysis is given for both the analytic and numerical solutions of the initial value problem for a system of ordinary differential equations. The standard linear stability analysis is reviewed, then it is shown that, using a proper choice of Liapunov function, a connected region of stable initial values of both the analytic and one leg k -step numerical solution can be approximated computationally. Correspondence between the one leg k -step solution and its associated linear k -step solution is stated. Constructive proofs are given for the existence of the stability regions for both the analytic and one leg k -step numerical solutions for a class of functions. An example is discussed.

Sufficient conditions for the convergence of methods for the numerical integration of a system of ordinary differential equations, possibly stiff, are presented. The asymptotic error formula for such a solution is developed. The existence of more stringent conditions for convergence of multi-derivative formulas over first derivative formulas is noted. A class of computationally A-stable formulas is presented, with notes on implementing a set of them in a variable stepsize, variable order method. Tests on one such implementation show the capabilities of such methods on stiff problems.

Kellogg, Douglas S., Jr. (Communicable Disease Center, Atlanta, Ga.), William L. Peacock, Jr., W. E. Deacon, L. Brown, and Carl I. Pirkle . Neisseria gonorrhoeae . I. Virulence genetically linked to clonal variation. J. Bacteriol. 85: 1274–1279. 1963.—One type, obtained from the purulent exudate of acute gonorrhea was maintained by 69 selective in vitro passages, at which point the organisms produced infections in human volunteers. A predominance of clonal types found in laboratory strains and a lack of ability to infect human volunteers resulted from 69 nonselective in vitro passages. Physiological and serological characteristics of the clonal types are compared. We are now in a position to study Neisseria gonorrhoeae organisms in their virulent form.

Activation energies are calculated by the bond-energy-bond-order (BEBO) and the bond-strength-bond-length (BSBL) methods for the reactions of C2H radicals with H2, CH4, and C2H6 and for the reactions of CN radicals with H2 and CH4. The BSBL technique accurately predicts the activation energies for these reactions while the BEBO method yields energies averaging 9 kcal higher than those observed. A possible reason for the disagreement is considered.

Activation energies are calculated by the bond-energy-bond-order (BEBO) and the bond-strength-bond-length (BSBL) methods for the reactions of C2H radicals with H2, CH4, and C2H6 and for the reactions of CN radicals with H2 and CH4. The BSBL technique accurately predicts the activation energies for these reactions while the BEBO method yields energies averaging 9 kcal higher than those observed. A possible reason for the disagreement is considered.

Many important problems in fluid dynamics, among other areas, are modeled by nonlinear parabolic differential systems with initial values given in one 'independent variable' x, and boundary values in the remaining dependent variables. Hyperbolic systems can sometimes be treated as a special case. For example, the inviscid flow case of the Navier-Stokes equations is a hyperbolic system, while the viscous flow case is elliptical. A survey of currently used numerical methods is in Richtmeyer and Morton. In subsonic flow cases, the nonlinear terms are small enough to be ignored, but these terms must be included in supersonic and hypersonic flow. These numerical calculations usually involve a finite difference mesh over the boundary value problem variables, resulting in a space discretization matrix equation which for the nonlinear system varies at each step in x, the independent variable representing time in the dynamic case or one of the space variable for the steady state case. Then this nonlinear system is solved as an initial value problem in x. The initial value problem is usually solved by a one step implicit method for reasons of cost and stability. Some methods based on finite element methods for the boundary value problem can be used, but successful methods are only available for the linear cases, such as subsonic flow problems.

This chapter presents a variable stepsize variable order method that is A-stable for orders up to 7, provided the second and third analytic derivatives can be computed. It presents methods for computing these higher derivatives for linear inhomogeneous systems of ordinary differential equations; it also highlights a similar treatment for equations arising in chemical kinetics. Numerical tests run on sample problems are described, showing the applicability of the treatment. ASTIFF is a FORTRAN program. The numerical method in ASTIFF is well suited to solving the system of equations, y' = Ay + g(t), where A is a matrix, g is a vector valued function of the independent variable, and y is the solution vector. By proper linearization of certain systems of ordinary differential equations, very good approximations to y″ and y″' can be made and thus, ASTIFF can be used to integrate any such system if it is analytically stable, with no restraint on the stepsize other than controlling the truncation error. Time-dependent forcing terms can be easily accounted for by using numerical differentiation of the nonautonomous terms.

Walsh, Martin J. (Communicable Disease Center, Atlanta, Ga.), Bobby C. Brown, Leonard Brown, and Carl I. Pirkle . Use of the chick embryo in maintaining and restoring virulence of Neisseria gonorrhoeae . J. Bacteriol. 86: 478–481. 1963.—Data based on its capabilities of producing acute urethritis in human male volunteers showed that Neisseria gonorrhoeae rapidly decreased in virulence after repeated subculture on chocolate agar medium. Cultures of a particular strain (GCM13) in the allantoic cavity of a developing chick embryo maintained virulence after 82 successive transfers. Another strain (GCF62), after loss of virulence through repeated subculture on chocolate agar, was again able to produce infection after 15 consecutive transfers in chick embryo. Thus, chick embryo apparently had the capability not only to maintain the virulence factor but also to reconstitute virulence. It is postulated that chick embryo serves as a selective medium for the growth of virulent gonococci, permitting rapid multiplication of these organisms and suppressing growth of the nonvirulent organisms.

ALTHOUGH GONORRHEA had been recognized clinically since antiquity, the etiological agent was not identified until 1879. By 1906, the gonococcus had been successfully cultured and differentially stained. With the advent of sulfonamides and penicillin, easy treatment became available for the cure of diagnosed cases. It soon became apparent, however, that the control of this disease would not be possible with therapeutic programs alone. During 1961, 265,665 cases of gonorrhea were reported in the US. 1 It was felt, however, that the reported number was about one tenth the actual incidence or more than 2,000,000 cases a year. Throughout the world, cases of gonorrhea have shown a steady increase, especially in teen-age groups. In almost every report, males outnumber females 3:1 in seeking medical attention for gonorrhea. With syphilis, however, statistics indicate that the prevalence is approximately the same in both sexes. Since both diseases are acquired in like manner, this