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11.
The intrinsic value approach amortizes over the life of the option, the difference between the stock price on the date of the grant and the exercise price of the option. The fair market value approach amortizes over the life of the option, the market value of stock options on the date of the grant. These approaches do not reflect the changes in the option–based compensation cost after the grant date. This paper proposes an economic cost approach that not only adjusts for the changes in the value of the options during its life but also records the issuance of the stock at fair market value on the exercise date. 相似文献
12.
Yu. A. Radin I. A. Grishin T. S. Kontorovich O. B. Panshina A. V. Chugin 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2006,40(2):113-119
Problems arising with connecting the second exhaust-heat boiler to the first exhaust-heat boiler under load in the case of
flow circuits of combined-cycle plants of type PGU-450 are considered. Similar problems exist for two-boiler single-turbine
units of type PGU-325 and for two-boiler single-turbine units of traditional steampower plants with an output of 200–300 MW
upon connection of the second furnace of a two-furnace boiler to the operating first furnace. Analysis of the temperature-induced
stressed state and of the cyclic strength of thick-walled elements of the steam-water conduit of PGU-450 and of two-furnace
boilers of two-boiler single-turbine units with an output of 200–300 MW (the check valve, the inlet header of the water economizer)
is used for determining the steam temperature differences in the high-pressure conduits to the steam turbine and the order
of connection of the second exhaust-heat boiler to the operating fist one. Modes of enabling a two-boiler single-turbine unit
of a combined-cycle plant, which are most “rigid” from the standpoint of thermal strength, are determined.
__________
Translated from élektricheskie Stantsii, No. 2, February 2006, pp. 11–17. 相似文献
13.
Groundwater and human development: challenges and opportunities in livelihoods and environment. 总被引:1,自引:0,他引:1
T Shah 《Water science and technology》2005,51(8):27-37
At less than 1000 km3/year, the world's annual use of groundwater is 1.5% of renewable water resource but contributes a lion's share of water-induced human welfare. Global groundwater use however has increased manifold in the past 50 years; and the human race has never had to manage groundwater use on such a large scale. Sustaining the massive welfare gains groundwater development has created without ruining the resource is a key water challenge facing the world today. In exploring this challenge, we have focused a good deal on conditions of resource occurrence but less so on resource use. I offer a typology of five groundwater demand systems as Groundwater Socio-ecologies (GwSE), each embodying a unique pattern of interactions between socio-economic and ecological variables, and each facing a distinct groundwater governance challenge. During the past century, a growing corpus of experiential knowledge has accumulated in the industrialized world on managing groundwater in various uses and contexts. A daunting global groundwater issue today is to apply this knowledge intelligently to by far the more formidable challenge that has arisen in developing regions of Asia and Africa, where groundwater irrigation has evolved into a colossal anarchy supporting billions of livelihoods but threatening the resource itself. 相似文献
14.
Comparison of nutrient cycling in a surface-flow constructed wetland and in a facultative pond treating secondary effluent. 总被引:1,自引:0,他引:1
There is a growing interest in the possibilities offered by combinations of waste stabilisation ponds (WSP) and constructed wetlands (CW). The purpose of our study was to compare treatment performances and nutrient cycling in a surface-flow wetland (SFW) and in a WSP treating secondary effluent. In the period between 2000 and 2003, a pilot SFW and a pilot WSP were constructed at the outlet of the wastewater treatment plant and their performance monitored while both were active under the same conditions. The SFW was planted with Phragmites australis and Eichhornia crassipes, while in the WSP development of algae was spontaneous. Performance efficiency was monitored by means of evaluation of physical and chemical parameters in water, by measurement of plant productivity and by analysis of N and P contents in biomass. The SFW with macrophytes proved more efficient in decreasing the suspended solids (64.6%), settleable solids (91.8%), organic N (59.3%), total N (38%), COD (67.2%) and BOD5 (72.1%) than the WSP. The WSP with algae was more efficient in treatment of ammonia nitrogen (48.9%) and ortho-phosphate (43.9%). The results of this study provide data that are of help in optimising combinations of SFW and WSP. 相似文献
15.
The number of intermediary levels between a manufacturer and the final market in a distribution channel varies from industry to industry. In some cases, none are used (i.e. the distribution function is vertically integrated), while several middleman levels are used in other cases (e.g. the use of a wholesaler, a jobber, and a retailer in the distribution of meat). In this paper we examine the effect of competition on the profit-maximizing length of the distribution channel. We find that the optimal number of middleman levels increases with the substitutability of products in the market, but that there are institutional limits on the maximum number of levels in a channel. The analysis also suggests that differences in the objectives of channel members (e.g. the maximization of total channel profit versus the maximization of each member's individual profit) affect optimal channel length: a goal of total channel profit maximization produces a channel at least as long as one of individual (non-co-operative) member profit maximization. The work thus complements existing research focusing on intra-channel (e.g. cost-based) explanations of channel length, using a framework similar to those investigating competitive incentives for vertical integration in distribution. 相似文献
16.
This article analyses the effects of action aimed at narrowing the gap between South Africa's ‘two agricultures’, specifically the effects of the Farmer Support Programme (FSP) on structural aspects of maize production under different marketing policies. This is done by assembling a sectoral linear programming model of the South African summer-rainfall grain-producing area. The emphasis is on the inclusion of supply, demand and production risk. Results show that the effects of a successful FSP on specific interest groups, e.g. consumers of a specific product, or producers in a specific region, depend on the marketing policy followed, as well as on the effectiveness of the FSP. The analysis accentuates the interrelationships in South African crop production and illustrates how past policies ignored regional comparative advantages, distorted regional development and affected social welfare. 相似文献
17.
18.
Reuse of wastewater is regarded as one important way to deal with the world's shortage of potable water. The authors focused on a disinfection system using micro-bubbles and evaluated its capability for wastewater reuse. This paper reports experimental results from examination of the basic characteristics of micro-bubbles and disinfection of secondary effluent by air or ozone micro-bubbles. The results suggest that when micro-bubbles are applied in an ozonation system it is possible to reduce the reactor size, the amount of ozone decomposition equipment needed and the ozone dose rate. 相似文献
19.
S J Chung S Balaji M Matheswaran T Ramesh I S Moon 《Water science and technology》2007,55(1-2):261-266
This study investigates the hybrid mediated electrochemical oxidation (HMEO) technology, which is a newly developed non thermal electrochemical oxidation process for organic destruction. A combination of ozone and ultrasonication processes to the mediated electrochemical oxidation (MEO) process is termed as hybrid mediated electrochemical oxidation. The electrochemical cell was developed in this laboratory. In the present study, several organic compounds, such as phenol, benzoquinone and ethylenediaminetetraacetic acid (EDTA), were chosen as the model organic pollutants to be destructed by the hybrid process. The organic destruction was monitored based on the CO2 generation and total organic carbon (TOC) reduction. The HMEO process was found to be extremely effective in the destruction of all the target organics chosen in this study. The information obtained from this study will provide an insight in adopting this technique for dealing with more recalcitrant organics (POPs). 相似文献
20.
Ponds following anaerobic reactors, such as Upflow Anaerobic Sludge Blanket (UASB) reactors, have been termed polishing ponds in the literature. The present paper analyses the removal of E. coli and helminth eggs in five UASB-polishing pond systems in Brazil. Since there were ponds in series, the total number of ponds was 10. The ponds had average retention times varying from 2 to 21 days, and depths ranging from 0.40 to 2.00 m. The shallow ponds in series, even with low retention times, were able to produce effluents complying with the coliform WHO guidelines for unrestricted irrigation (< or = 1000 MPN/100 ml). An equation for the coliform decay coefficient was proposed: Kb (dispersed flow) = 0.710H(-0955) (20 degrees C). The equation highlights the inverse relationship between the pond depth and the decay coefficient. All polishing pond systems were able to produce effluents with helminth eggs concentrations predominantly equal to zero, and satisfying the WHO guidelines for unrestricted and restricted irrigation (< or = 1 egg/L, arithmetic mean). The approximate range of helminth eggs removal efficiency was predicted satisfactorily. 相似文献