[en] Short communication

[en] The traditional node wake-up mechanism usually takes the huge cost of network energy and fails to consider the expensive price of the sensor node. In order to improve this shortcoming, this paper studies the wireless sensor network monitoring area coverage rate of 100% in the existing an improved node wake-up mechanism problem is proposed in the node wake-up mode. Firstly, the problem is transformed into SAT (the satisfiability of Boolean equation), and then the MiniSAT solver is used to solve the answer. The wireless sensor network is reached with as few working nodes as possible. The complete coverage of the monitoring area and the reduction of network energy consumption show that the new node wake-up mechanism can reduce the number of active nodes in the wireless sensor network monitoring area, improve network energy utilization, and reduce the application of WSN (wireless sensor network). Cost, driving the application of wireless sensor networks. (paper)

[en] For forging process in the production of high energy consumption, this paper proposes an energy-saving scheduling model. This article will take the forgings oven minimum hours minimum energy-saving scheduling for the production target of minimizing the idle time are established to aim at oven, for the purpose of energy saving. Using the Hungarian method to hierarchical model, and finally got the forging production of energy-saving of optimal production plan, and uses case to verify the feasibility of scheduling model. (paper)

[en] Highlights: • Biomass grindability index based solely on mean mass diameters is unreliable. • Standard biomass grindability determination test should utilize volumetric samples. • Biomass grindability index should base on both energy consumption and fines increase. -- Abstract: The main objective of the research was to develop a method of biomass grindability determination (Biomass Grindability Index), which would allow for a clear classification of different types of solid biofuels in terms of their milling properties. The objective of the research included also the assessment of the possibility of adaptation of the existing coal grindability determination methods for evaluation of biomass milling. In the course of research, the biomass grindability determination method was modified to obtain the highest possible reliability of the developed index. The scope of laboratory tests being focused on influence of circumferential speed of test mill beaters, particle size distribution of sample, test time, mass and volume of sample. The results of laboratory and industrial tests have shown that the grindability index based on mean particle sizes of feed and product is unreliable. Grindability of different types of biomass, comminuted in beater mills, can be clearly determined by the index expressed as the ratio of energy consumption during the test to the amount of specified product size fraction. During the study laboratory test results obtained for proposed grindability index were compared to other grindability indices determined for utilized in research types of biomass.

[en] Manufacturing sector consumes a significant amount of energy globally. Machine tools are one of the major equipment in manufacturing sector and hence major consumer of energy. The electrical energy consumed by the machine tools results in emission of harmful gases and substantial stress on environmental. This work focuses on selection of optimum cutting parameters to minimize specific energy consumption (SEC) during turning of Al 6061 with tungsten carbide inserts in dry condition. Experiment are planned using L₂₇ orthogonal array and Taguchi method is applied to determine optimum and most influencing cutting parameters for minimizing SEC. Results shows that feed is the dominating factor followed by cutting speed and depth of cut. The optimum value of feed (mm/rev), cutting speed (m/min) and depth of cut (mm) are found 0.12, 46.2 and 1.0 respectively. Further the energy consumption maps are developed to analyse the influence of cutting parameters on specific energy consumption. The developed energy consumption maps can be used for correlating the region of minimum SEC with selected cutting parameters. (paper)

[en] Whereas most of the data are, naturally, about oil, a few figures concern nuclear energy. There is in Part 1 a flow chart of worldwide primary energy consumption by type, from 1974 to 1986, where nuclear energy consumption can be seen in relation to oil, gas, coal and hydro. The same is also given for the regions of the South. In section 3/18 the numbers of nuclear plants in construction and operation are listed separately for developing countries, centrally planned economies and industrialized countries, for 1986. (qui)

[en] An estimate is presented of the energy balance of Quebec for 1991 (unconventional energy sources excluded), and the definitive energy balance for 1990. The estimates for 1991 are based on sales data for the whole year for electric power, petroleum products, and natural gas, and on the first 9 months of data for coal and coke. In 1990, the energy consumption of Quebec reached 32.2 M TEP (tonnes of equivalent petroleum), or a decrease of 1.8% with respect to 1989. In 1991, it reached 31.1 M TEP, or a decrease of 3.5% with respect to 1990. The electric power consumption in 1991 was 149.1 TWh, an increase of 1.0% with respect to 1990, attributed in part to the economic effects of the recession. The consumption of petroleum products for energy uses attained 93.5 M bbl in 1991, or a drop of 7.3% with respect to 1990. This drop is also attributed to economic reasons. Natural gas sales in 1991 totalled 193.2 billion ft³, or a decrease of 2.3% from 1990. In the residential sector, natural gas sales fell 8%, while sales in the industrial and commercial sectors fell 1.6% and 1.3% respectively. Data on energy consumption are given as a function of the energy source (petroleum, coal and coke, natural gas and electric power), as a function of the consuming sector (for electric power and natural gas) or as a function of the nature of the product (for petroleum products). 4 figs., 4 tabs

[en] Highlights: • Emerging economies are the main source of the increase in energy consumption. • There are three mediating effects of labor costs on energy intensity. • Rising labor costs have a negative total effect on energy intensity. • The TFP growth is the main way in which labor costs affect energy intensity. The existing literatures have not systematically studied and reached a consensus on the relationship between labor costs and energy intensity. This study introduces the mediation model to solve the theoretical disputes, and proposes three mediating effects of labor costs on energy intensity, i.e., substitution effect, industrial structure effect, and total factor productivity effect. The bootstrap confidence interval method and causal steps approach are used to test the mediating effects and decompose total effect. As indicated by the empirical study using panel data of 22 emerging economies, the total effect of rising labor costs on energy intensity is negative. The contributions of substitution effect, industrial structure effect and total factor productivity effect to the total effect are −21.8%, 8.9% and 76.4% respectively. Therefore, the total factor productivity growth turns out to be the main way in which labor costs affect energy intensity in emerging economies. These findings provide new empirical support for the Neo-classical growth theory and Environment Kuznets Curve hypothesis from the perspective of labor costs.

[en] In table 3 the share of nuclear primary energy consumption in North America, Western Europe, Australia and Japan in 1973, 1980, 1986 can be seen in comparison with oil, gas, coal and hydro. 5 tabs. (qui)

[en] This paper presents a driving simulator to be used by train drivers for training their driving skills in terms of energy-efficiency. In railway operations, previous experiences have shown differences in energy consumption up to 20 % among train drivers for the same journey in similar operational conditions. This shows great saving potentials in both economic and environmental terms. For this reason, railway companies wishing to become more efficient must encourage their train drivers to balance the energy consumption towards the minimum threshold. In this sense, driving simulators are a good complement for training courses on energy-saving best practices given to train drivers, where they can put into practice the learned contents. The developed driving simulator consists in an Excel spreadsheet including an accurate energy consumption model, which was previously developed from real measurements on different train services. The fact of being an Excel spreadsheet provides a familiar interface to train drivers, making easier its use, and becomes an affordable tool for small and medium size freight private railway companies. Furthermore, the fact of being a non-real-time simulation makes possible to perform a journey of several hours in a few minutes, thus being able to test different driving strategies for the same train journey in a short time period. In this paper, the driving simulator was applied to the Valencia-Cuenca-Aranjuez railway line operated by Renfe Operadora with Diesel Multiple Units. The results are given in terms of fuel consumption, costs of fuel and CO2 emissions and enable train drivers to find by themselves the most efficient way to drive the train between two stations. Finally, this driving simulator may serve as the basis for training and evaluating train drivers in order to set up a bonus/penalty policy for rewarding the most efficient train drivers and achieve an overall energy consumption reduction. (Author)