256 research outputs found

    Search for a New Conceptual Bookkeeping Model: Different Levels of Abstraction

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    Nowadays, every bookkeeping system used in practice is automated. Most bookkeeping software and integrated information systems are based on databases. In this paper, we develop a new conceptual bookkeeping model which is not based on manual techniques, but which is applicable in a database environment. The model is designed as a composition of equations. The startingpoint of these equations is the well-known accounting equation. In the development of the model, several levels of abstraction are distinguished: from an abstract level to a more concrete level. Every level of abstraction is described by one equation. This equation has both an input-function and an output-function. With the development of this model, the gap between the bookkeeping literature and bookkeeping practice has been reduced.bookkeeping;accounting information systems;conceptual modeling

    Walkability of Suburban Retrofits of the Washington DC Area: Immersion into Qualitative Constructs

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    The majority of the United States population is living in the suburbs, and yet the suburban built fabric has developed with spatial conditions that have failed to prove their efficacy on environmental, social or economic terms. Most contemporary architectural and urban theorists agree that the suburban condition is inherently problematic. In a 2010 Ted Talk, architect and urban designer Ellen Dunham-Jones discusses the problematic state of the suburban built condition, citing dependence on the vehicle, sparseness of built form, environmental costs, transportation costs, and even increased obesity rates (Dunham-Jones 2010). Because the suburbs comprise the majority of our “urbanized” areas in land-use, population, and economic activity, it is important that designers are able to rectify this American man-made landscape and build public spaces that are worth caring about. Dunham-Jones indicates that there have been demographic shifts in our culture that are calling for more urban lifestyles in the suburbs. She calls for the re-habitation, re-development, and re-greening of areas in the suburbs that have failed in their pursuits for sustainable human habitation. This capstone discusses a specific type of re-development: suburban retrofit, or the urbanization of a suburban area through the development of walkable built form as a means of generation of activity. Walkability is central to this capstone and serves as a generator of activity and performance of public space. This capstone seeks to answer two main questions. First, what are the constructs of walkability based on the writings and works of urban theorists, designers, and experts regarding suburban and urban built form? Second, in the suburban retrofits of the Washington DC area, how have these constructs of walkability been executed and what is the experiential quality of their built form? Thus, this capstone offers two main contributions. It establishes a set of urban form constructs to quantitatively analyze and qualitatively assess walkability. Second, it uses some of these constructs of walkability to assess three case studies of suburban retrofits in the Washington DC area—Bethesda Row, Mosaic District Fairfax, and Arts District Hyattsville. This metropolitan area is one of the most active markets for suburban retrofit in the United States (Dunham-Jones 11, 2009). It’s mass-transit system and internal urban structure have encouraged the development of high(er)-density nodes of walkable neighborhoods in the ring of suburbs outside the city. CONSTRUCTS OF WALKABILITY In the context of this capstone, the concept of walkability has been subdivided into four principles: density, edge condition, integration, and diversity. These principles have then been subdivided into the nine constructs of walkability. The principle of density involves (A) density of dwelling units and (B) density of built form. The principle edge condition involves the (C) definition of public space, (D) permeability of the built edge, and (E) the transparency of the built edge. The principle of integration involves the (F) integration into surrounding context and (G) access and block size. The principle of diversity involves both the (H) diversity of building age and the (I) diversity of program. These constructs are defined, diagrammed, and operationalized in this capstone. ­­­ CASE STUDY ANALYSIS OF SUBURBAN RETROFITS Some of these constructs of walkability are used to quantitatively analyze and qualitatively assess three case studies of suburban retrofits in the Washington DC area—Bethesda Row, Mosaic District Fairfax, and Arts District Hyattsville. The theoretical background of the constructs of walkability are taken into consideration and critical in the on-site assessment process, which includes sketching, diagramming, photography, and descriptive writing. These methods also deliver insight into the qualitative character and performance of each case study. The case study analysis offers an immersion into three suburban retrofits and aims to answer the following questions: What is the experiential quality of the constructs of walkability as established in this capstone? How are suburban retrofits living up the walkability promised in their development? The importance of the qualitative constructs emerged as a takeaway of this capstone, especially integration into the surrounding context. An unexpected finding of this capstone is the importance, value, and validity of on-site qualitative analysis in a study of urban form. Using the skill set of a designer of urban form and an understanding of the constructs established within this capstone, the experiential quality of the studied areas can be fully comprehended through sketching, photography, and descriptive writing. This capstone is intended to contribute more than the establishment of a simple checklist for walkable design that can be quantified and replicated. The qualitative results of the case studies reinforce the importance of the perceptual character of the qualitative constructs and the validity of on-site analysis. These qualitative constructs can only be understood in a deep immersion with the site

    Effects of Computer Assisted Tier II Interventions by Gender on Math and Reading Achievement for Remediated Students

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    Response to Intervention (RtI) is a current reform initiative being examined by educators, politicians, and proponents of differentiated education. RtI has tiers of intervention designed to meet the various academic needs of all students. RtI has been developed as an educational methodology to increase student achievement through various problem-solving techniques, through the implementation of specific interventions based on each student’s individual needs, and through data-based decision making regarding the interventions used. The implementation of RtI requires schools to shift current educational paradigms of how services are delivered to students. This quantitative causal comparative study compared the effectiveness of PLATO alone, a computer-assisted instructional program, as a reading and math intervention to the combination of PLATO and differentiated instruction provided by a highly qualified teacher for fifth and sixth grade students. The study took place at two intermediate schools (grades 5 and 6) within a suburban school district in the central region of Arkansas. Fourteen intact Tier II intervention classrooms were identified to participate in the study, two at each school. Classrooms were selected because they were composed of students who were classified as being at-risk due to not scoring proficient or barely scoring proficient on the 2010 ACTAAP Augmented Benchmark Exam. Students within the classrooms were selected by stratified random sampling to ensure the overall populations as well as subpopulations of race and genders were represented. A 2 x 2 factorial analysis of covariance was conducted to investigate each of the four hypotheses. The covariates were the math and reading scaled scores on the previous year’s ACTAAP Augmented Benchmark Exam. The independent variables were type of instruction and gender, and the dependent variables were math and reading achievement measured by the scaled scores on the 2011 ACTAAP Augmented Benchmark Exam. This study found no significant interaction effects between type of instruction and gender in the four hypotheses. However, type of instruction as a main effect was significant in three of the four hypotheses. PLATO combined with a highly qualified teacher was more effective on math achievement for both grade levels and on reading achievement for at-risk fifth graders. Gender was a significant main effect in fifth grade reading with the female students scoring higher than the male students did. Within the sixth grade reading groups, although the PLATO with the highly qualified teacher group did score higher than the PLATO alone group did, the result was not significant. Therefore, the overall results of this study indicated the addition of a highly qualified teacher to the PLATO, CAI intervention, significantly improved at-risk students’ achievement for these fifth and sixth grade students within Central Arkansas

    Search for a New Conceptual Bookkeeping Model:Different Levels of Abstraction

    Get PDF
    Nowadays, every bookkeeping system used in practice is automated. Most bookkeeping software and integrated information systems are based on databases. In this paper, we develop a new conceptual bookkeeping model which is not based on manual techniques, but which is applicable in a database environment. The model is designed as a composition of equations. The startingpoint of these equations is the well-known accounting equation. In the development of the model, several levels of abstraction are distinguished: from an abstract level to a more concrete level. Every level of abstraction is described by one equation. This equation has both an input-function and an output-function. With the development of this model, the gap between the bookkeeping literature and bookkeeping practice has been reduced.

    Pair configurations to molecular activity coefficients: PAC-MAC

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    This thesis provides an overview of the development of the Pair Configuration to Molecular Activity Coefficient (PAC-MAC) model. PAC-MAC is a computational method to predict thermodynamic miscibility properties of various molecular solutions. Examples of calculated thermodynamic miscibility properties are vapor-liquid equilibrium (VLE) diagrams, mixing free energies and Flory-Huggins χ-interaction parameters. Within PAC-MAC, a unique approach is used by combining the quasi-chemical approximation of Guggenheim with the use of classical force fields. The quasi-chemical approximation is used in foregoing models for miscibility prediction (UNIFAC, COSMO-RS) whereas classical force fields are used in methods preserving the molecular 3D structure (molecular dynamics and Monte Carlo simulations). The combination of the quasi-chemical approximation with classical force fields results in a quick and accurate method containing, besides the force field parameters, only two empirically optimized parameters.SABICSoft Matter Chemistr

    Een Nieuw Conceptueel Model Voor Boekhouden Met Verschillende Abstractniveaus

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    Boekhouden wordt in de literatuur besproken als een techniek om financiele gegevens vast te leggen en te verwerken op een zodanige wijze dat een balans en een winst- en verliesrekening kunnen worden opgesteld. Steeds wordt hierbij gebruik gemaakt van een handmatig boekhoudsysteem, dat gebaseerd is op een handmatig boekhoudmodel. Onder boekhoudmodel wordt hier verstaan, het traject dat een gegeven aflegt tussen het moment van invoer in de boekhouding en de uiteindelijke output in de vorm van balans en winst- en verliesrekening. Ook de boekhoudtheorieen, die de regels beschrijven voor de vastlegging en verwerking van gegevens binnen het model, zijn gebaseerd op een handmatige boekhouding. Tegenwoordig is in de praktijk echter iedere boekhouding geautomatiseerd. De meeste boekhoudpakketten en geintegreerde informatiesystemen zijn gebaseerd op een of meer databases. In deze paper wordt een nieuw conceptueel boekhoudmodel ontwikkeld dat niet gebruikmaakt van het handmatige model, maar toepasbaar is in een database-omgeving. Het model is ontwikkeld op basis van een stelsel van vergelijkingen, met als uitgangspunt de balansvergelijking. Bij de ontwikkeling van het nieuwe model worden verschillende abstractieniveaus onderscheiden. Ieder abstractieniveau wordt door middel van een vergelijking beschreven. Deze vergelijking kent zowel een input- als een outputfunctie. Met de ontwikkeling van dit nieuwe conceptuele boekhoudmodel is de discrepantie tussen de op het handmatig model gebaseerde boekhoudliteratuur en de gecomputeriseerde boekhoudpraktijk opgeheven.

    Zinc- and cadmium-isotope evidence for redox-driven perturbations to global micronutrient cycles during Oceanic Anoxic Event 2 (Late Cretaceous)

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    This study uses organic-rich sediments from the Tarfaya Basin, Morocco, to assess the Cd- and Zn-isotope response to dramatic global palaeoenvironmental change during the Cenomanian–Turonian interval (Late Cretaceous). These organic-rich continental-margin deposits include an expression of Oceanic Anoxic Event 2 (OAE 2, ∼94 Ma), an interval associated with the spread of low-oxygen marine environments and widespread burial of organic-rich sediments. Due to placement of the Tarfaya Basin in a region of upwelling and relatively constant local environmental conditions, the stratigraphic variations in δ114Cd and δ66Zn values largely reflect changes in the seawater isotopic composition of the sub-surface proto-North Atlantic Ocean. Positive shifts of ∼0.2–0.3‰ away from background values in δ114Cd and δ66Zn are observed during the main phase of the positive carbon-isotope excursion associated with OAE 2. These isotopic shifts are coeval with decreases in Cd/TOC and Zn/TOC ratios and thus imply that drawdown of isotopically light Cd and Zn from seawater inventories was a result of extensive burial of these metals in organic-rich marine sediments globally. Low δ66Zn values during the Plenus Cold Event, a cooler episode during OAE 2, are similar in timing and magnitude to variations found in the English Chalk (Eastbourne, UK) and support the inference of a global control on these isotopic excursions. The δ66Zn values during the Plenus Cold Event are taken to record global oxygenation, possibly including the remobilization of isotopically light Zn from continental-margin sediments. A considerably smaller change in δ114Cd values for this interval implies that the Cd- and Zn-isotope systems can provide information about slightly different environmental processes, with global seawater composition with respect to Zn also being influenced by the magnitude of oxic removal sinks and isotopically light Zn input fluxes from sediments and hydrothermal fluids
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