3,871 research outputs found
Mark-up Pricing in South African Industry
No full textThis paper investigates the extent of the mark-up of the South African manufacturing sector, taking into account a number of characteristics of its component industries. We find significant mark-ups to be present in the South African manufacturing industry. In comparative terms, the mark-up is approximately twice that found for the US manufacturing sector. We find that industry concentration exerts a positive influence on the mark-up over marginal cost whilst an indicator of competitiveness suggests that an increase in an industry's competitiveness relative to other industries allows it to raise its mark-up. However, within-industry increases in competitiveness reduces the mark-up. We also analyze the impact of import and export penetration. Both import and export penetration serve to lower the mark-up. The impact of the business cycle on mark-up indicates that the mark-up is countercyclical. Finally, accounting for intermediate inputs significantly lowers the absolute size of the mark-up, controlling for the industry's concentration ratio. However, relative to findings on the US manufacturing sectors, SA manufacturing mark-ups remain approximately twice as large.
Numerical Analysis of Damage Iinitiation and Development in Bends of Steel Pipelines
No full textGasses and fluids are transported via an extensive infrastructure of steel pipelines. In the design of pipeline systems the use of elbows (pipe bends) is important because their flexibility makes them able to sustain significant deformations. These bends can be subjected to permanent deformations due to various load combinations which can lead to progressive material damage. There are three stages commonly observed in ductile damage: void nucleation, growth and coalescence. When subjected to varying bending loads low cycle fatigue damage may occur. Within this research project Finite Element Analysis is used to simulate the response of pipeline bends. Two element types are implemented to model a pipe bend, the classical shell element and an efficient tube element (pipe elbow element), respectively. To predict the structural response when subjected to monotonic loading a damage model is implemented for both elements. When subjected to cyclic loading three phases can be identified. During the first few cycles the permanent deformation increases rapidly. After some cycles, the rate of permanent deformation stabilizes until the point of response degradation. In order to capture this response a new material model, based upon the afore mentioned model, is proposed. Experiments have indicated that this model is well suited to determine the point of material failure.Structural MechanicsCivil Engineering and Geoscience
Embedding population dynamics in mark-recapture models
No full textMark-recapture methods use repeated captures of individually identifiable animals to provide estimates of properties of populations. Different models allow estimates to be obtained for population size and rates of processes governing population dynamics. State-space models consist of two linked processes evolving simultaneously over time. The state process models the evolution of the true, but unknown, states of the population. The observation process relates observations on the population to these true states.
Mark-recapture models specified within a state-space framework allow population dynamics models to be embedded in inference ensuring that estimated changes in the population are consistent with assumptions regarding the biology of the modelled population. This overcomes a limitation of current mark-recapture methods.
Two alternative approaches are considered. The "conditional" approach conditions on known numbers of animals possessing capture history patterns including capture in the current time period. An animal's capture history determines its state; consequently, capture parameters appear in the state process rather than the observation process. There is no observation error in the model. Uncertainty occurs only through the numbers of animals not captured in the current time period.
An "unconditional" approach is considered in which the capture histories are regarded as observations. Consequently, capture histories do not influence an animal's state and capture probability parameters appear in the observation process. Capture histories are considered a random realization of the stochastic observation process. This is more consistent with traditional mark-recapture methods.
Development and implementation of particle filtering techniques for fitting these models under each approach are discussed. Simulation studies show reasonable performance for the unconditional approach and highlight problems with the conditional approach. Strengths and limitations of each approach are outlined, with reference to Soay sheep data analysis, and suggestions are presented for future analyses
CLASSICAL STUDIES:TO 155-TH ANNIVERSARY OF A.E. ALEKTOROV
No full textThe article, written in the genre of the response to read the book, devoted to the 155 anniversary since the birth of A. E. Alektorov. The author attempts to comprehend and describe the publishing and pedagogical activity of A.E. Alektorov for example, fundamental bibliographic work
The A.E. Coppard Papers at Syracuse
No full textSome of the most choice collections in the Manuscript Department of Syracuse University Libraries are also among the most modest in extent. The papers of English author and poet A.E. Coppard fit into both categories. Housed comfortably in a single box, fifty-five letters, three short stories in holograph and one speech provide a close look at Coppard\u27s literary theories, criticism, opinions of his own work and that of a few others, reaction to approaches regarding dramatizing, filming or televising his prose works, dealings with publishers, and his activities on behalf of world peace through the Authors\u27 World Peace Appeal in the early 1950\u27s
St. Catharines Collegiate Institute Entrance Examination Letter
No full textA letter from the principal of St. Catharines Collegiate Institute, A. E. Coombs, notifying the mother of Helen Smith of her examination results. Helen received honours for her entrance examination mark and the letter reads as follows: "Dear Helen, I am glad to be able to inform you that Helen Smith of 39 Church St. obtained Honours at the entrance examination with a total of 517 marks out of 650. The less fortunate H. Smith was Howard Smith of 122 Queenston St, whose name appears in the pass list. Yours truly A.E. Coombs
Covariance matrix-based fire and flame detection method in video
No full textThis paper proposes a video-based fire detection
system which uses color, spatial and temporal information.
The system divides the video into spatio-temporal blocks and
uses covariance-based features extracted from these blocks
to detect fire. Feature vectors take advantage of both the spatial and the temporal characteristics of flame-colored regions. The extracted features are trained and tested using a support vector machine (SVM) classifier. The system does not use a background subtraction method to segment moving regions and can be used, to some extent, with non-stationary cameras. The computationally efficient method can process 320×240 video frames at around 20 frames per second in an ordinary PC with a dual core 2.2 GHz processor. In addition, it is shown to outperform a previous method in terms of detection performance
Surface morphology of silica nanowires at the nanometer scale
No full textNanowires used in these experiments were manufactured from commercial optical fibers by the "microheater brushing technique", a top-down technique originally developed to manufacture nanowires from glasses with low processing temperature [15]. A commercial telecom optical fiber (SMF-1300/1550-9/125-0.25-10641, manufactured from Oz Optics), was held by two clamps mounted on translational stages (WSX-300 provided by Rockwell Automation) and heated by a ceramic microheater (manufactured by NTT-AT) with a bore 20 mm long and 2 mm wide (Fig. 1a) in air. The fiber was pulled with speeds in the range of few µm/s at both extremities while being heated up. The stages motion was computer controlled and mass conservation allowed for a great degree of control over the taper shape. The microheater temperature (T) was estimated to be ~ 1280 °C and was controlled by adjusting the current (I) flowing through it. The current was stable within 0.01A and was kept at 0.01A above the level at which the fiber broke. Fig. 1b reports the microheater calibration curve performed after the samples were manufactured by inserting a wire thermocouple inside the microheater bore and coincided within ~ 20°C with the calibration curve provided by the manufacturer. Regression of the experimental data showed that the maximum T in the microheater is related to the current flowing through it by T = 373 + 328 * I, implying that during the nanowire manufacture T inside the microheater is stable within ~ ± 3 °C. The inset of Fig. 1b shows the temperature profile inside the microheater for two different currents: experimental data is fit by a parabola and shows a hot zone smaller than 3 mm
Tools for Ferreting-out Fraud: a Book Review of Mark Nigrini's Forensic Analytics
No full textBook review of
MARK J. NIGRINI, Forensic Analytics: Methods and
Techniques for Forensic Accounting Investigations, John
Wiley & Sons (Hoboken, NJ: Wiley, 2020, ISBN: 978-0-470-
89046-2, 463 pages, $95.00)
The Ethical Economy of Customer Coproduction
No full textIn this article, the author argues that customer coproduction should be understood as an expression of a large-scale trend toward the increasing power and relevance of social production. Social production consists in the self-organized systems of (mostly immaterial) production that have evolved around the diffusion of networked information and communication tech-nologies. An analysis of the genealogy of social production is shared; this includes tracing it to the process of re-mediation of social relations put in motion by the expansion of the capitalist economy into the fields of culture and consciousness and the concomitant socialization of production relations. The author then argues that social production, including customer coproduction, follows a very particular economic logic—that is, an ethical economy where value is related to social impact rather than monetary accumulation. A detailed analysis of the logic of this ethical economy is offered; it draws out some implications for the successful management of ever more customer-centric brands, whereby the consumers are directly involved in the processes that add value
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