540 research outputs found

    Cost Accounting and Pricing Improvement at Helmond Print: Using Xeikon Digital Colour Printing Equipment: A Case study

    Get PDF
    Helmond Print B.V., a (fictional) Dutch print provider, is facing competitive problems. The student is expected to step into the role of an independent expert advising Helmond Print''s owner and manager. The first objective is to let the student find out, from a piece of qualitative and quantitative information about Xeikon N.V. machines, that the cost structure is much different than currently assumed. The student should try to improve the cost calculations, which will require linear and both non-linear regression analysis. A second objective is to make the student realize that the incorrect cost calculations affected Helmond Print''s pricing policy and may have lead to the competitive problems faced now. The student should therefore link their investigations to pricing, search for the weak spots in the current pricing policy and make suggestions for improvement. (Note: a solution to the case can be obtained by simple request)management and organization theory ;

    Methodology for cokemaking technology selection for operating conditions and expansion of iron and steel works

    Full text link
    Selection of cokemaking technology within an Iron & Steel Works (I&SW) setting is a complicated problem, involving analysis of coal quality, coke demand and supply, environmental regulations, and the plant energy balance. The methodology involves coal blend selection, preparation, charging, cokemaking and quenching technology selection to meet the blast furnaces’ coke quality requirements and the I&SW energy balance. Hatch’s mass and energy balance, OPEX, CAPEX, Energy/CO2 and Financial Models provide the client with NPV/IRR ranking and sensitivity analysis to assist in selecting the best strategy amongst by-product or heat recovery ovens, charging and quenching systems for replacement or expansion programs

    Methodology for Cokemaking Technology Selection

    Get PDF
    The objective of this article is the selection of cokemaking technology within an Iron & Steel Works (I&SW), involving analysis of coal quality, coke demand and supply, environmental regulations, and the plant energy balance. The methodology involves coal blend selection, preparation, charging, cokemaking and quenching technology selection to meet the blast furnaces’ coke quality requirements and the I&SW energy balance. Hatch’s mass and energy balance, OPEX, CAPEX, Energy/CO2 and Financial Models provide the client with NPV/IRR ranking and sensitivity analysis to assist in selecting the best strategy amongst by-product or heat recovery ovens, charging and quenching systems for replacement or expansion programs. The developedmethodology was successfully applied for development of coal and cokemaking strategy, estimation of required cokemaking capacity for the metallurgical giant, which incorporates four integrated iron and steel works, two stand alone coke plant and several coal and iron ore mines. Some of Hatch’s recommendationsare already implemented and tested by the client. The optimum selection of cokemaking technologies requires a careful analysis of the I&SW and companyspecific requirements in order to develop a techno-economic analysis that will provide the optimum strategy to get the most from existing assets and to ensure competitive future coke production. Development by Hatch methodology could be successfully applied for selection and construction of green site cokemaking facilities as well as for brown field modernizations. Keywords: By-product cokemaking, heat recovery cokemaking, energy balance, financial analysi

    Calculations and Competitive Benchmarking: A Case study: Xeikon N.V.

    Get PDF
    Xeikon N.V. is a young NASDAQ-listed company in the digital colour printing market. First of all, the student is expected to step into the role of an independent expert advising Xeikon''s CEO. Although it is already clear that digital colour printing is competitive mainly at relatively small order quantities, the student is expected to give more specific information about the quantities for which Xeikon equipment is competitive. This will require different kinds of break-even analysis. Furthermore, students should analyse cost data using a learning curve model. In doing so, they should address the limitations of the model, test the usefulness in this situation and recognize that learning is not the right term in this context. The investigations require the use of regression analysis. (Note: a case solution can be obtained by simple request)management and organization theory ;

    Parametrizations of Inclusive Cross Sections for Pion Production in Proton-Proton Collisions

    Full text link
    Accurate knowledge of cross sections for pion production in proton-proton collisions finds wide application in particle physics, astrophysics, cosmic ray physics and space radiation problems, especially in situations where an incident proton is transported through some medium, and one requires knowledge of the output particle spectrum given the input spectrum. In such cases accurate parametrizations of the cross sections are desired. In this paper we review much of the experimental data and compare to a wide variety of different cross section parametrizations. In so doing, we provide parametrizations of neutral and charged pion cross sections which provide a very accurate description of the experimental data. Lorentz invariant differential cross sections, spectral distributions and total cross section parametrizations are presented.Comment: 32 pages with 15 figures. Published in Physical Review D62, 094030. File includes 6 tex files. The main file is paper.tex which has include statements refering to the rest. figures are in graphs.di

    Identification campaign of supernova remnant candidates in the Milky Way - I: Chandra observation of G308.3-1.4

    Full text link
    ROSAT all-sky survey (RASS) data have provided another window to search for supernova remnants (SNRs). In reexamining this data archive, a list of unidentified extended X-ray objects have been suggested as promising SNR candidate. However, most of these targets have not yet been fully explored by the state-of-art X-ray observatories. For selecting a pilot target for a long-term identification campaign, we have observed the brightest candidate, G308.3-1.4, with Chandra X-ray observatory. An incomplete shell-like X-ray structure which well-correlated with the radio shell emission at 843 MHz has been revealed. The X-ray spectrum suggests the presence of a shock-heated plasma. All these evidences confirm G308.3-1.4 as a SNR. The brightest X-ray point source detected in this field-of-view is also the one locates closest to the geometrical center of G308.3-1.4, which has a soft spectrum. The intriguing temporal variability and the identification of optical/infrared counterpart rule out the possibility of an isolated neutron star. On the other hand, the spectral energy distribution from Ks band to R band suggests a late-type star. Together with a putative periodicity of \sim1.4 hrs, the interesting excesses in V, B bands and H-alpha suggest this source as a promising candidate of a compact binary survived in a supernova explosion (SN).Comment: 19 pages, 10 figures, 2 tables, accepted for publication in Ap

    Contribution of Distinct Homeodomain DNA Binding Specificities to Drosophila Embryonic Mesodermal Cell-Specific Gene Expression Programs

    Get PDF
    Homeodomain (HD) proteins are a large family of evolutionarily conserved transcription factors (TFs) having diverse developmental functions, often acting within the same cell types, yet many members of this family paradoxically recognize similar DNA sequences. Thus, with multiple family members having the potential to recognize the same DNA sequences in cis-regulatory elements, it is difficult to ascertain the role of an individual HD or a subclass of HDs in mediating a particular developmental function. To investigate this problem, we focused our studies on the Drosophila embryonic mesoderm where HD TFs are required to establish not only segmental identities (such as the Hox TFs), but also tissue and cell fate specification and differentiation (such as the NK-2 HDs, Six HDs and identity HDs (I-HDs)). Here we utilized the complete spectrum of DNA binding specificities determined by protein binding microarrays (PBMs) for a diverse collection of HDs to modify the nucleotide sequences of numerous mesodermal enhancers to be recognized by either no or a single subclass of HDs, and subsequently assayed the consequences of these changes on enhancer function in transgenic reporter assays. These studies show that individual mesodermal enhancers receive separate transcriptional input from both I–HD and Hox subclasses of HDs. In addition, we demonstrate that enhancers regulating upstream components of the mesodermal regulatory network are targeted by the Six class of HDs. Finally, we establish the necessity of NK-2 HD binding sequences to activate gene expression in multiple mesodermal tissues, supporting a potential role for the NK-2 HD TF Tinman (Tin) as a pioneer factor that cooperates with other factors to regulate cell-specific gene expression programs. Collectively, these results underscore the critical role played by HDs of multiple subclasses in inducing the unique genetic programs of individual mesodermal cells, and in coordinating the gene regulatory networks directing mesoderm development.National Institutes of Health (U.S.) (Grant R01 HG005287

    Understanding the complexity of a catalyst synthesis: Co-precipitation of mixed Cu,Zn,Al hydroxycarbonate precursors for Cu/ZnO/Al<sub>2</sub>O<sub>3</sub> catalysts investigated by titration experiments

    Get PDF
    Co-precipitation of Cu,Zn,(Al) precursor materials is the traditional way of synthesizing Cu/ZnO/(Al2O3) catalysts for industrial methanol synthesis. This process has been investigated by titration experiments of nitrate and formate solutions. It was found that the solidification of the single components proceeds sequentially in case of nitrates: Cu2+ is precipitated at pH 3 and Zn2+ (as well as Al3+) near pH 5. This behavior prevents a homogeneous distribution of all metal species in the initial precipitate upon gradual increase of pH and requires application of the constant pH micro-droplet method. This effect is less pronounced if formate instead of nitrate is used as counter ion. This can be explained by the strong modification of the hydrolysis chemistry of the metal ions due to the presence of formate anions, which act as ligands and buffer. A formate-derived Cu/ZnO/Al2O3 catalyst was more active in methanol synthesis compared to a nitrate-derived sample although the same crystallographic phases were present in the precursor after co-precipitation and ageing. The effect of precipitation temperature was studied for the binary CuZn nitrate model system. Increasing the temperature of co-precipitation above 50 °C leads to down-shift of the precipitation pH of Zn2+ by a full unit. Thus, in warm solutions more acidic conditions can be used for complete co-precipitation, while in cold solutions, some Zn2+ may remain dissolved in the mother liquor at the same precipitation pH. The higher limit of temperature is given by the tendency of the initial Cu precipitate towards formation of CuO by oxolation. On the basis of these considerations, the empirically determined optimal pH and temperature conditions of the industrially applied synthesis can be rationalized
    corecore