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Initial Cost (initial + cost)

Distribution by Scientific Domains

Engineering	27%
Chemistry	18%
Business, Economics, Finance and Accounting	18%

Selected Abstracts

Computational economy improvements in PRISM

INTERNATIONAL JOURNAL OF CHEMICAL KINETICS, Issue 9 2003
Shaheen R. Tonse
The Piecewise Reusable Implementation of Solution Mapping (PRISM) procedure is applied to reactive flow simulations of (9-species) H2 + air combustion. PRISM takes the solution of the chemical kinetic ordinary differential equation system and parameterizes it with quadratic polynomials. To increase the accuracy, the parameterization is done piecewise, by dividing the multidimensional chemical composition space into hypercubes and constructing polynomials for each hypercube on demand. The polynomial coefficients are stored for subsequent repeated reuse. Initial cost of polynomial construction is expensive, but it recouped as the hypercube is reused, hence computational gain depends on the degree of hypercube reuse. We present two methods that help us to identify hypercubes that will ultimately have high reuse, this being accomplished before the expense of constructing polynomials has been incurred. One method utilizes the rate of movement of the chemical trajectory to estimate the number of steps the trajectory would make through the hypercube. The other method defers polynomial construction until a preset threshold of reuse has been met; an empirical method which, nevertheless, produces a substantial gain. The methods are tested on a 0-D chemical mixture and reactive flow 1-D and 2-D simulations of selected laminar and turbulent H2 + air flames. The computational performance of PRISM is improved by a factor of about 2 for both methods. © 2003 Wiley Periodicals, Inc., Int J Chem Kinet 35: 438,452, 2003 [source]

A parallel multigrid solver for high-frequency electromagnetic field analyses with small-scale PC cluster

ELECTRONICS & COMMUNICATIONS IN JAPAN, Issue 9 2008
Kuniaki Yosui
Abstract Finite element analyses of electromagnetic fields are commonly used for designing various electronic devices. The scale of the analyses becomes larger and larger, therefore, a fast linear solver is needed to solve linear equations arising from the finite element method. Since a multigrid solver is the fastest linear solver for these problems, parallelization of a multigrid solver is quite a useful approach. From the viewpoint of industrial applications, an effective usage of a small-scale PC cluster is important due to initial cost for introducing parallel computers. In this paper, a distributed parallel multigrid solver for a small-scale PC cluster is developed. In high-frequency electromagnetic analyses, a special block Gauss, Seidel smoother is used for the multigrid solver instead of general smoothers such as a Gauss, Seidel or Jacobi smoother in order to improve the convergence rate. The block multicolor ordering technique is applied to parallelize the smoother. A numerical example shows that a 3.7-fold speed-up in computational time and a 3.0-fold increase in the scale of the analysis were attained when the number of CPUs was increased from one to five. © 2009 Wiley Periodicals, Inc. Electron Comm Jpn, 91(9): 28, 36, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecj.10160 [source]

The optimal timing of the transfer of hidden reserves in the German and Austrian tax systems

INTELLIGENT SYSTEMS IN ACCOUNTING, FINANCE & MANAGEMENT, Issue 2 2002
Manfred FrühwirthArticle first published online: 16 DEC 200
The lower-of-cost-or-market principle implies that assets may be sold above book value, by which hidden reserves are disclosed. To avoid taxation of these hidden reserves, in German-speaking countries companies are allowed to transfer them to a newly purchased asset within a fixed time period. In this paper, the optimal timing of hidden reserves transfers is developed with special attention to the term structure of interest rates and interest rate risk, and using the replicating principle known from the field of finance. The paper presents one model under certainty and, as a generalization of this model, another model under interest rate risk. In both models, the criterion used for decision-making is the value of the right to transfer, which can be interpreted as the initial cost of a replicating/hedging strategy for tax payments saved/incurred. In the model under certainty, the net present value concept is used to derive the value of the right to transfer. The procedure used in the model under interest rate risk is a combination of flexible planning and the no-arbitrage approach common in derivatives pricing. It is shown that the right to transfer hidden reserves with flexible timing is equivalent to an American-style exchange option. In addition, the impact of term-structure volatility on the value of the right to transfer is analyzed. The technique presented in this paper can also be used to solve other timing problems resulting from trade-offs between early and late tax payments/tax benefits. Copyright © 2002 John Wiley & Sons, Ltd. [source]

Minimizing shell-and-tube heat exchanger cost with genetic algorithms and considering maintenance

INTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 9 2007
Philippe Wildi-Tremblay
Abstract This paper presents a procedure for minimizing the cost of a shell-and-tube heat exchanger based on genetic algorithms (GA). The global cost includes the operating cost (pumping power) and the initial cost expressed in terms of annuities. Eleven design variables associated with shell-and-tube heat exchanger geometries are considered: tube pitch, tube layout patterns, number of tube passes, baffle spacing at the centre, baffle spacing at the inlet and outlet, baffle cut, tube-to-baffle diametrical clearance, shell-to-baffle diametrical clearance, tube bundle outer diameter, shell diameter, and tube outer diameter. Evaluations of the heat exchangers performances are based on an adapted version of the Bell,Delaware method. Pressure drops constraints are included in the procedure. Reliability and maintenance due to fouling are taken into account by restraining the coefficient of increase of surface into a given interval. Two case studies are presented. Results show that the procedure can properly and rapidly identify the optimal design for a specified heat transfer process. Copyright © 2006 John Wiley & Sons, Ltd. [source]

Optimum matching parameters of an MPPT unit used for a PVG-powered water pumping system for maximum power transfer

INTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 6 2006
Mehmet Akbaba
Abstract Photovoltaic generator (PVG)-powered water pumping has the potential to bring potable water to millions of people in developing countries. However, due to the high initial cost of PVG units, sophisticated load matching is required between the water pumping system and PVG, in order to be able to extract maximum available power from an available PVG unit at all solar radiation levels. This requires an intermediate circuitry between the PVG unit and the motor driving the water pump, which is usually termed as maximum power point trackers (MPPT). This present paper therefore investigates the optimum matching parameters of a power conditioning circuit, which is composed of a double step-up dc,dc converter (DSUC). This MPTT circuit is used for interfacing a permanent magnet (PM) motor-driven water pumping system to a PVG for extracting maximum available power from PVG, hence maximizing the energy utilization efficiency and price,performance ratio of the whole system. It is shown that two key parameters of the DSUC, which are the duty cycle and chopping frequency, are dominating the performance of the whole system, and they are interrelated and load dependent. Therefore, optimum values of these parameters need to be determined. An example system is provided in which a complete modelling is presented in time domain and through numerical experiments it is demonstrated how the optimum values of these two key matching parameters can be determined for a given system. The MPPT circuit used in this investigation is suitable for optimum matching of all types of loads to PVG units, provided that an optimum frequency,duty cycle pair is determined for the choppers in DSUC for every 5% bands of solar radiation between 20 and 100%. Copyright © 2005 John Wiley & Sons, Ltd. [source]

SPLITTING AND BREAKING OF PISTACHIO NUTS WITH STRIKING AND HEATING

JOURNAL OF FOOD PROCESS ENGINEERING, Issue 3 2008
H.I. CEM BILIM
ABSTRACT The objective of this study was to investigate the effects of heating process and striking on splitting and breaking of pistachio nuts and obtaining their kernels without damage. For this purpose, heating process (350C) was applied to pistachio nuts. Heated nuts were dropped onto the rotating disk and then thrown to strike the wall of the container by centrifuge effect . Striking velocity was adjusted with a rotating disk that was driven by an electrical engine. Three different disk rotations (400, 500 and 600/min) with three different moisture contents of pistachios (6.5, 22.0 and 42.5%) were evaluated in the experiments. Results indicated that the highest splitting rate was obtained as 29.33% at 22.0% moisture content with 400 1/min disk velocity. The most healthy kernel percentage obtained from unsplit pistachio nuts was 25.76% at 6.5% moisture content with 500 1/min disk velocity. Additionally, the study results showed that only the heating process had no affect while heating and crushing combinations increased splitting and obtaining the kernels. PRACTICAL APPLICATIONS Consumption of healthy foods is very important for human health. Kirmizi variety of pistachio nuts contains a high ratio of unsplit pistachio nuts after harvest. These pistachio nuts are either consumed as appetizers or used in the sweets sector after extracting the inner part (kernel). The economical value of unsplit pistachio nuts is very low. For this reason, pistachio nut processing plants try to split them or extract the inner part without causing any damage. Unsplit pistachio nuts are split by hand or by primitive hand tools, such as hammer or pliers, and then extracted. This method is not healthy. This study is one of the limited studies concerning automatic, quick and economic splitting and extraction of pistachio nuts. After handling problems like splitting and extracting the kernel of pistachio nuts, pistachio nut processing plants will achieve a healthy pistachio nut production. This study offers a new system for healthy pistachio nut production, with low initial cost, lower wages and in less time. [source]

The Effect of Life Cycle Cost Information on Consumer Investment Decisions Regarding Eco-Innovation

JOURNAL OF INDUSTRIAL ECOLOGY, Issue 1 2010
Josef Kaenzig
Summary Life cycle cost (LCC) computations are a well-established instrument for the evaluation of intertemporal choices in organizations, but they have not been widely adopted by private consumers yet. Consumer investment decisions for products and services with higher initial costs and lower operating costs are potentially subject to numerous cognitive biases, such as present-biased preferences or framing effects. This article suggests a classification for categorizing different cost profiles for eco-innovation and a conceptual model for the influence of LCC information on consumer decisions regarding eco-innovation. It derives hypotheses on the decision-making process for eco-innovation from a theoretical perspective. To verify the hypotheses, the publication reviews empirical studies evaluating the effects of LCC information on consumer investment decisions. It can be concluded that rather than finding ways to make customers pay more for environmentally sound products, the marketing challenge for eco-innovation should be reconceptualized as one of lowering customers' perceived initial cost and increasing awareness of LCC. Most existing studies report a positive effect of LCC information on the purchase likelihood of eco-innovations. Disclosing LCC information provides an important base for long-term thinking on the individual, corporate, and policy levels. [source]

Economic costs of cataract surgery using a rigid and a foldable intraocular lens,

OPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 4 2001
Asfa J. Afsar
Summary Optimal delivery of healthcare requires consideration of various costs. A foldable intraocular lens (IOL) is more expensive than an equivalent rigid IOL. However, surgical and post-operative costs may make a foldable IOL economically preferable. We compared the economic costs of cataract surgery plus implantation of a foldable IOL with implantation of a rigid IOL. Prospective audit of the clinical records of 82 pseudophakes; 39 implanted with a rigid IOL and 43 implanted with a foldable IOL by one surgeon. Average follow-up periods were 25±7 months and 23±5 months respectively. There was no difference between the two groups for the follow-up period (P=0.55), number of post-operative complications (P=0.25) or cost of post-operative visits (P=0.83). The cost of single-use theatre equipment was greater for the rigid-IOL group (P=0.0001). The total identified cost per patient was greater for the foldable-IOL group (P=0.0001). Despite possible technical advantages, implantation of the foldable IOL did not provide an economic benefit, either in the initial cost or in the costs of post-operative care. Over the 2-year period, implanting with the rigid IOL cost, on average, £57 less per patient. Despite this economic difference, a cost-benefit analysis is required, since other factors may be more important. [source]

Economical Advantages of Low-Pressure Plasma Polymerization Coating

PLASMA PROCESSES AND POLYMERS, Issue 6 2005
Hirotsugu Yasuda
Abstract Summary: Low-pressure plasma polymerization coating, as described in this paper, is an ultimately green process that uses a minimum amount of substances and produces a minimum amount of effluent and hence does not require an environmental remediation process. The super-green aspect of the processing entirely changes the equation for the viability of the process in industrial applications. The main hampering factors for the low-pressure processes are 1) psychological fear of vacuum processes, 2) relatively high initial equipment costs, and 3) a lack of adequate cost estimate for the entire process. In many cases, the first two factors are enough for planners to shy away from this promising technology. However, when one examines the overall cost of processing as a whole, the cost of initial equipment often is not the decisive factor. Such cases are presented in the nano-film coating applied in corrosion protection of aluminum alloys, steel, and surface-state modification of contact lenses. The benefits of environmental friendliness, non-hazardous processing and superior performance of products that can be achieved only by low-pressure plasma polymerization coatings are more than enough to compensate the initial cost of the equipment. For nanofilm (20 nm) coatings, the most expensive annual operation cost is for wastewater treatment, which is much more than the initial cost of vacuum plasma polymerization reactor. [source]

The Effect of Life Cycle Cost Information on Consumer Investment Decisions Regarding Eco-Innovation

The antecedents of donor commitment to voluntary organizations

NONPROFIT MANAGEMENT & LEADERSHIP, Issue 1 2005
Adrian Sargeant
The past decade has seen a rapid growth in the number of regular or so-called committed giving schemes. Charities have been increasingly eager to solicit donors onto a low-value monthly donation, collected automatically from their bank account or credit card. Although the initial costs of donor acquisition are higher than for cash donations, charities find that committed givers are less likely to lapse and therefore offer substantially higher lifetime values over time. In this article, we examine to what extent these individuals are truly committed, that is, whether they are more committed than occasional cash givers and the factors that might drive that commitment. The results of a series of ten focus groups conducted on behalf of five large national charities are reported and a model of the antecedents of commitment hypothesized. Implications for fundraising strategy are explored. [source]