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Constant rate costs

From the New York Times Magazine, December 25,1955, we read The United States Treasury reported that it costs eight-tenths of a cent to print dollar bills, and that of the billion and a quarter now in circulation, a billion have to be replaced annually. Assume that the bills are put into circulation at a constant rate and continuously, and that they are withdrawn from circulation without regard to their condition, in a random manner. [Pg.335]

In most instances people of different income levels are involved in different projects at a rather constant rate. Thus, it does not effect the exactness of a budget estimate too much using the budget per person (or cost of labour) averaged across all income levels. Minor adjustments may be made, if the particular project deviates considerably from the normal work distribution. [Pg.27]

Applications for a national patent or at the International Patent Office may cost up to an equivalent of US 3,000 per application for a search report and the examination. A similar amount can be assumed for the involvement of a patent attorney as long as only formalities are concerned. Creative work by a patent attorney office (e.g. formulation of the claim or of defending statements) as well as translations result in the extra cost of about US 100-300 equivalent per hour, depending on the qualification of the person who deals with it. Thus, the effective cost of the patent application may rise up to US 8,000-10,000 per country. Annuities for a national patent are raised as a constant rate per year or increase during the life-span of a patent. The figure of US 100-300 per year and country (or per patent certificate from international patent organizations) may serve as a clue for what must be expected. [Pg.93]

The hypothesis forwarded by Kimura and others (Kimura, 1968 King and Jukes, 1969) proposed a way to solve all such empirical problems. In their view if it is assumed that the vast majority of amino acid substitutions are selectively neutral, then substitutions will occur at approximately a constant rate (assuming that mutation rates do not vary over time) and it will be easy to maintain lots of polymorphism within populations with apparently no cost of selection. [Pg.316]

Optimization of an existing SMBR system Maximizing the purity of a fraction and the yield of a compormd and minimizing the solvent consumption are chosen as the three objective functions. Six decision variables were used in this optimization study, the switching time (fj), the number of columns in sections II, III, and IV, the amormt of raffinate produced, and the eluent consumed. Since the optimization of an existing system is considered, the number of columns, their lengths and their diameters were kept fixed, but the sensitivity of the results to the number of columns on the Pareto shift was studied. The flow rate in section II and the temperature of the columns were also kept constant in order to allow a comparison of the optimum results at constant operation cost. Of the two throughput parameters, the raffinate flow rate (j3) was selected as a decision variable, in order to determine the optimum raffinate flow rate for a constant feed flow rate. [Pg.931]

Dimethyl azodicarboxylate (manufactured by Tokyo Kasei Kogyo Co., Japan) was purchased from CTC Organic, 792 Windsor Street, Atlanta, GA 30315. Overheating of dimethyl azodicarboxylate should be avoided because of the danger of explosion. Distillation should be conducted from a temperature-controlled bath in the hood behind a safety shield. The material used distilled at 71-72°C (2 mm), at a bath temperature of Q4-86°C. It is important that the addition of this compound to the reaction mixture be carried out at a constant rate without interruption because it tends to freeze in the syringe needle. The checkers explored the use of diethyl azodicarboxylate because of its lower cost and wider availability. However, the corresponding hydrazine derivative Is more difficult to separate from the jJ-laclone product of this step. [Pg.4]

Uranium deposits occur in many countries, but as shown in Table 12.4 the economically recoverable reserves, like oil and gas reserves, are primarily located outside of Europe. The OECD Nuclear Energy Agency and the International Atomic Energy Agency (IAEA, 2008) expects that it will be possible to double the global uranium extraction at cost below US 80/ kgU to approximately 120,000 tU per year in 2016. At a constant rate of extraction these resources would allow for uranium extraction well into the 2040s. [Pg.259]

Very few auxiliary components are required in such compact devices. Hydrogen is supplied at a constant rate as required, depending on the electric capacity. Hydrogen reservoirs are of a disposable cartridge type that contain a cheap catalyst such as Raney-Ni or fluorinated-Mg2 NiH4. The future cost in 2020 is expected to be less than 5/kg-NaBH4 and 0.1/kWh using an advanced production process introduced in the section below. [Pg.251]

When the useful life of the equipment has been established, the proportional procurement costs per year can be found. If the equipment is used at a constant rate over the course of its useful life, these are independent of the number of measurements. The determining factors are simply the purchase price of the equipment and its estimated useful life. [Pg.214]

One of the simplest models of demand is to use an estimate of the average demand. This average demand, assuming a constant rate each period, can then be used to understand the effect of production costs or transport costs on inventory levels. Such models are appropriate when we deal with products in situations with predictable demand, that is, low forecast error. In particular, we will focus on the... [Pg.2020]

Together with the aqueducts, the Romans also advanced the technology of water distribution from the aqueducts to multiple sites—baths, residences, fountains, etc. Plumbing is derived from the Latin word plumbum which means lead. Piping used in Roman times included lead pipes, masonry channels as well as earthenware pipes. The water was delivered to baths and some public homes at a constant rate. The cost of the water was charged based on the pipe cross-sectional area, which served as a restriction orifice (Chanson, 2002,2008). [Pg.195]

The most common high precision laboratory instruments are the thermal mass flow meters. (They are among the most expensive and can cost over 2000. ) The principle is based on an energy balance either the entire flow or a slipstream is heated at a constant rate and the temperature rise is recorded. The temperature (or temperature difference) of the fluid is measured and amplified it is proportional to the mass flow rate ... [Pg.220]

To understand such pressures, consider the relationship between a retailer and a manufacturer in a supply chain. Assuming that the retailers warehouse supplies many stores, the demand at the warehouse can be considered to be relatively stable, with a constant rate of D units per unit time. Given an ordering cost and a holding cost at the retailer, it is optimal for the retailers order sizes to follow the economic order quantity to minimize retailer ordering and holding costs. [Pg.86]

Faber et al. (1986) have compared drying rates in air and in steam-fluidized beds of pulverized coal. They found the inversion temperature of about 180°C above which the steam-drying rate in the constant-rate period in fluidized bed drying exceeds that in (dry) air drying. For a 2000-kg/h dryer for alumina, the capital cost was 20% lower for the steam dryer, while the total energy cost was lower by 15%. No credit was given to the steam produced in the steam dryer. [Pg.92]

Chakravarty and Martin [29] consider a related problem that allows for demand to decay exponentially with time, where the function has a known and constant rate of decay. Production by the seller and ordering by the buyer incur a fixed set-up charge, but holding cost is not considered in the model the... [Pg.350]

Building on this, Mendelson and Whang [105] extend [104] to include multiple classes of users, the authors derive incentive-compatible pricing controls for an M/M/1 queue with constant delay cost per unit job. As defined by Mendelson and Whang, optimal incentive-compatible means that the arrival rate and execution priorities jointly maximize the expected net value of the system while being determined on a decentralized basis , i.e., individual customers determine their service level and whether to join the queue. [Pg.363]

We first describe a basic model which will be used in this section as a reference point when we review results in this problem class. Most problems studied in this area have a similar structure and share many assumptions made in this basic model. A manufacturer produces one product on a single production line at a constant rate for a customer with a constant demand rate for the product which must be satisfied without backlog. At the manufacturer s end, there is a fixed setup cost for each production run, and a linear inventory holding cost. At the customer s end, there is a linear inventory holding cost. Between the manufacturer and the customer, there is a fixed delivery cost per order delivered from the manufacturer to the customer, regardless of the order size. The problem is to find a joint cyclic production and delivery schedule such that the total cost per unit time, including production setup costs, inventory costs at both the manufacturer and the customer, and transportation costs, is minimized over an infinite planning horizon. [Pg.717]


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See also in sourсe #XX -- [ Pg.131 ]




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