[en] We investigate and compare several generic depreciation methods to assess the effectiveness of possible policy measures with respect to the depreciation schedules for investments in combined heat and power plants in the United States. We assess the different depreciation methods for CHP projects of various sizes (ranging from 1 MW to 100 MW). We evaluate the impact of different depreciation schedules on the tax shield, and the resulting tax savings to potential investors. We show that a shorter depreciation cycle could have a substantial impact on the cost of producing power, making cogeneration more attractive. The savings amount to approximately 6-7 percent of capital and fixed operation and maintenance costs, when changing from the current system to a 7 year depreciation scheme with switchover from declining balance to straight line depreciation. Suggestions for further research to improve the analysis are given

[en] This paper examined the relationship between energy prices and the Canadian-United States dollar real exchange rate. The researchers evaluated the standard Amano-van Norden (AvN) equation formulated to demonstrate that higher real energy prices lead to a depreciation of the Canadian dollar. Major developments in the Canadian energy market were discussed, as well as policy initiatives designed to address Canada's trade balance by increasing energy exports. The study examined the AvN equation using Monte Carlo experiments to determine the parameter stability of the equation. Results indicated that the co-integrating relationship in the standard AvN equation were no longer supported. Structural break tests were used to demonstrate that major changes in Canada's energy policies and cross-border trade and investment strategies have led to an increase in the Canadian dollar's value when energy prices are high. The study presented a new equation designed to account for Canadian dollar's appreciation since 2003. It was concluded that net energy exports in the 1990s outweighed the negatives associated with Canada's energy-intensive production processes. 39 refs., 6 tabs., 10 figs

[en] Light Emitting Diode (LED) luminaires and lamps are energy-saving and environmental friendly alternatives to traditional lighting products. However, current luminous flux depreciation test at luminaire and lamp level requires a minimum of 6000 h testing, which is even longer than the product development cycle time. This paper develops an accelerated test method for luminous flux depreciation to reduce the test time within 2000 h at an elevated temperature. The method is based on lumen maintenance boundary curve, obtained from a collection of LED source lumen depreciation data, known as LM-80 data. The exponential decay model and Arrhenius acceleration relationship are used to determine the new threshold of lumen maintenance and acceleration factor. The proposed method has been verified by a number of simulation studies and experimental data for a wide range of LED luminaire and lamp types from both internal and external experiments. The qualification results obtained by the accelerated test method agree well with traditional 6000 h tests. - Highlights: • We develop an accelerated test method for LED luminaires and lamps. • The method is proposed based on a “Boundary Curve” concept. • The parameters of the boundary curve are extracted from LM-80 test reports. • Qualification results from the proposed method agree with ES requirements.

[en] A single item production system has been considered in this proposed work. It is also assumed that the system produced some imperfect items. For this purpose a screening process has been considered here to separate the perfect quality items and imperfect quality items. The perfect quality items have a demand in the market which is depended on the advertisement of the product as well as the selling price of the product. The imperfect quality items are sold in a lot after the production period. As the depreciation rate of the product increases and number of imperfect product increases then there will be a risk in the system of loss in profit. So a risk function has been considered here depending on the depreciation rate of the demand and imperfect production rate of the item. Keeping these phenomenon the proposed model has been maximize for profit and minimize for the risk with numerical illustration.

[en] This study investigates the time-varying volatility of two major crude oil markets, the West Texas Intermediate (WTI) and Europe Brent. A flexible autoregressive conditional heteroskedasticity (ARCH) model is used to take into account the stylized volatility facts such as clustering volatility, asymmetric news impact and long memory volatility among others. The empirical results indicate that the intensity of long-persistence volatility in the WTI is greater than in the Brent. It is also found that for the WTI, the appreciation and depreciation shocks of the WTI have similar impact on the resulting volatility. However, a leverage effect is found in Brent. Although both the estimation and diagnostic evaluations are in favor of an asymmetric long memory ARCH model, only the WTI models provide superior in the out-of-sample forecasts. On the other hand, from the empirical out-of-sample forecasts, it appears that the simplest parsimonious generalized ARCH provides the best forecasted evaluations for the Brent crude oil data. (author)

[en] The purpose of this study is to present a rational depreciation method for a pyroprocess cost calculation. Toward this end, the so-called advanced decelerated depreciation method (ADDM) was developed that complements the limitations of the existing depreciation methods such as the straight-line method and fixed percentage of declining-balance method. ADDM was used to show the trend of the direct material cost and direct labor cost compared to the straight-line or fixed percentage of the declining-balance methods that are often used today. As a result, it was demonstrated that the depreciation cost of the ADDM, which assumed a pyroprocess facility's life period to be 40 years with a deceleration rate of 5%, takes up 4.14% and 27.74% of the pyroprocess unit cost ($781/kg heavy metal) in the 1st and final years, respectively. In other words, it was found that the ADDM can cost the pyroprocess facility's capital investment rationally every year. Finally, ADDM's validity was verified by confirming that the sum of the depreciation cost by year, and the sum of the purchasing cost of the building and equipment, are the same

[en] This study investigates the time-varying volatility of two major crude oil markets, the West Texas Intermediate (WTI) and Europe Brent. A flexible autoregressive conditional heteroskedasticity (ARCH) model is used to take into account the stylized volatility facts such as clustering volatility, asymmetric news impact and long memory volatility among others. The empirical results indicate that the intensity of long-persistence volatility in the WTI is greater than in the Brent. It is also found that for the WTI, the appreciation and depreciation shocks of the WTI have similar impact on the resulting volatility. However, a leverage effect is found in Brent. Although both the estimation and diagnostic evaluations are in favor of an asymmetric long memory ARCH model, only the WTI models provide superior in the out-of-sample forecasts. On the other hand, from the empirical out-of-sample forecasts, it appears that the simplest parsimonious generalized ARCH provides the best forecasted evaluations for the Brent crude oil data.

[en] In real situations, the value of public goods will be reduced or even lost because of external factors or for intrinsic reasons. In this work, we investigate the evolution of cooperation by considering the effect of depreciation of public goods in spatial public goods games on a square lattice. It is assumed that each individual gains full advantage if the number of the cooperators n_c within a group centered on that individual equals or exceeds the critical mass (CM). Otherwise, there is depreciation of the public goods, which is realized by rescaling the multiplication factor r to (n_c/CM)r. It is shown that the emergence of cooperation is remarkably promoted for CM > 1 even at small values of r, and a global cooperative level is achieved at an intermediate value of CM = 4 at a small r. We further study the effect of depreciation of public goods on different topologies of a regular lattice, and find that the system always reaches global cooperation at a moderate value of CM = G − 1 regardless of whether or not there exist overlapping triangle structures on the regular lattice, where G is the group size of the associated regular lattice

[en] Objectives: Exploring the variable effect of the degree of smoking dependence on the level of anxiety and depression symptoms among medical students. Methodology: This cross-section study, conducted in the Department of Pharmacology, College of Medicine, Al-Mustansiriya University, Baghdad-Iraq from December 2010 to May 2011, involving 300 medical students selected by cluster random sampling techniques. Those students completed the Hamilton rating scale for anxiety, Zung self-report depression scale and the Fagerstrom test for nicotine dependence with a value of six or more regarded as heavy smokers, and a value less than six considered as light smokers. Results: The response rate was 89%, heavy smokers were significantly older and start smoking at an earlier age than non- and light smokers (p=0.001). Heavy smokers associated with high chance of depressive symptoms in comparison with non-smokers (OR=4.8, C.I.=1.752-13.677) and light smokers (OR=4.2, C.I.=1.042-17.161). Regarding anxiety symptoms, heavy smokers demonstrate high chance of anxiety symptoms in comparison with non-smokers (OR=5.2, C.I.=1.826-15.176), and light smokers (OR=4.5, C.I.=1.318-15.526). Conclusions: Heavy smokers differ from non- and light smokers, associated with high risk of anxiety and depression, therefore heavy smoking tends to deteriorate rather than ameliorate these symptoms. (author)

[en] This paper simulates environmental protection investment (EPI) response strategies by constructing a discrete model of the interaction between EPI and economic growth while constantly improving EPI response strategies according to the simulation results. The oriented elasticity EPI was superior to the perfect elasticity EPI from the perspective of environmental quality. However, oriented elasticity EPI was not always superior to perfect elasticity EPI from the perspective of gross products. Thus, when the proportionality coefficient between the range of investment change and range of environmental quality change is less than or equal to 1.4, the maximum output of oriented elasticity EPI is higher than the maximum output of perfect elasticity EPI. The gap between oriented and perfect elasticity EPI decreases when proportionality coefficient increases. When the value of proportionality coefficient is greater than 1.4, oriented elasticity EPI is not superior to perfect elasticity EPI. Therefore, in view of the above defects, we proposed and simulated a minimal maintenance EPI. The environmental quality improves quickly and does not fluctuate after reaching the maximum value, and the minimum value of environmental quality is also higher than that when the above two EPI response strategies are used. In addition, the increased rate of environmental depreciation will improve environmental quality quickly, but reduce the level of economic development. The growth of environmental protection technology will promote both environmental quality improvements and economic development. Population growth will decrease environmental quality and economic development.