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Introducing new constructs for data modelling and column generation in LP modelling languages
Through popular implementation of structured query language (SQL) and query-by-example(QBE) relational databases have become the de-facto industry standard for data modelling.We consider the indices, sets, and the declarative form of Linear Programming (LP) modelling languages and introduce new constructs which provide direct link to the database systems. The models constructed in this way are data driven and display a dynamicstructure. We then show how this approach can be naturally extended to include column generation features stated in procedural forms within an otherwise declarative modelling paradigm
Sets and indices in linear programming modelling and their integration with relational data models
LP models are usually constructed using index sets and data tables which are closely related to the attributes and relations of relational database (RDB) systems. We extend the syntax of MPL, an existing LP modelling language, in order to connect it to a given RDB system. This approach reuses existing modelling and database software, provides a rich modelling environment and achieves model and data independence. This integrated software enables Mathematical Programming to be widely used as a decision support tool by unlocking the data residing in corporate databases
Diffraction from visible lattice points and k-th power free integers
We prove that the set of visible points of any lattice of dimension at least
2 has pure point diffraction spectrum, and we determine the diffraction
spectrum explicitly. This settles previous speculation on the exact nature of
the diffraction in this situation, see math-ph/9903046 and references therein.
Using similar methods we show the same result for the 1-dimensional set of k-th
power free integers with k at least 2. Of special interest is the fact that
neither of these sets is a Delone set --- each has holes of unbounded inradius.
We provide a careful formulation of the mathematical ideas underlying the study
of diffraction from infinite point sets.Comment: 45 pages, with minor corrections and improvements; dedicated to
Ludwig Danzer on the occasion of his 70th birthda
Dark side of calling, The: a partial test of the work as calling theory (WCT) using the veterinarian occupational well-being study (VOWS)
2022 Spring.Includes bibliographical references.Although research on the concept of calling has blossomed in the last several decades, less is known about how and when having a calling may lead to less desirable outcomes (i.e., the so-called "dark side" of calling). Recently, the Work as Calling Theory (WCT - Duffy, Dik, Douglass, England, & Velez, 2018) proposed certain working conditions and individual characteristics that may lead to these negative outcomes. Many veterinarians experience lower psychological well-being (e.g., depression, thoughts of suicide, moral distress) as a result of occupational stressors and job characteristics. According to WCT, this may paradoxically be attributed to the reported likelihood that a high number of veterinarians find their work deeply meaningful and identify their work as a calling, often from a very early age. Using path analysis techniques with a sample of associate veterinarians (n = 149), the current study found support for the hypothesized relationships between living a calling and job satisfaction, which was mediated by the disengagement aspect of burnout. The relationship between living a calling and disengagement was found to be moderated by perfectionistic standards, in that, for individuals with both high perfectionistic standards and high sense of calling, increased disengagement was reported. Furthermore, while interpretation should be made with caution, the results indicated that the exhaustion subscale of burnout was also associated with living a calling and job satisfaction and acted as a mediator. Finally, the hypothesized moderators of living a calling and several characteristics of the work environment (i.e., coworker and supervisor support) and personality traits (i.e., conscientiousness, need for achievement, and self-esteem) demonstrated some relationships with burnout, and provide tentative, initial starting points to be more fully explored in other studies. This study contributes to the field in providing initial support for some of the proposed relationships within WCT and has several practical implications for veterinarians
Method of Discrete Orthogonal Basis Restoration
A method is described for utilizing discrete orthogonal basis to restore signal system, such as radio or sound waves and/or image system such as photographs or medical images that become distorted while being acquired, transmitted and/or received. The signal or image systems are of the linear type and may be represented by the equation [B] [o]= [i] wherein [o] is an original signal or image, [i] is a degraded signal or image and [B] is a system transfer function matrix. The method involves estimating a signal-to-noise ratio for a restored signal or image. Next, is the selecting of a set of orthogonal basis set functions to provide a stable inverse solution based upon the estimated signal-to-noise ratio. This is followed by removing time and/or spatially varying distortions in the restored system and obtaining an appropriate inverse solution vector
In Search of the Irish Hill Cemetery in Bulloch County
A project by Susan Moody and Dan Good to find and document the Irish cemetery of Bulloch County lore. This paper discusses the findings of the project, explains the methodology used in data collection, and reviews some of the history associated with Irish immigration into Georgia and the Bulloch County area.https://digitalcommons.georgiasouthern.edu/bchs-pubs/1018/thumbnail.jp
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