挤压凹模型腔轮廓的合理设计

挤压凹模型腔轮廓形状不同,其挤压力和所消耗的能量也不同。介绍一种力能消耗最少的凹模型腔设计方法,并将其力能消耗与楔形凹模作了比较。

China's INDC and non-fossil energy development

Global climate change promotes the energy system reform. Achieving a high proportion of renewable energy becomes the major countries＇ energy strategy. As proposed in its Intended Nationally Determined Contributions （INDC）, China intends to raise the proportion of non-fossil energy in primary energy consumption to about 20% by 2030. That ambitious goal means the non-fossil energy supplies by 2030 will be 7-8 times that of 2005, and the annual increase rate is more than 8% within the 25 years. Besides, the capacity of wind power, solar power, hy- dropower and nuclear power reaches 400 GW, 350 GW, 450 GW, and 150 GW respectively, and China＇s non-fossil power capacity is even greater than the U.S.＇s total power capacity. In addition, the scale of natural gas increases. Consequently, by 2030, the proportion of coal falls from the current 70% to below 50%, and the CO2 intensity of energy consumption decreases by 20% compared with the level of 2005, which play important roles in significantly reducing the CO2 intensity of GDE Since China has confirmed to achieve the CO2 emissions peak around 2030, at that time, the newly added energy demand will be satisfied by non-fossil energy, and the consumption of fossil fuel will stop growing. By 2030, non-fossil energy accounts for 20%, and the large scale and sound momentum of new and renewable energy industry will support the growth of total energy demand, which plays a key role in CO2 emissions peaking and beginning to decline, and lays the foundation for establishing a new energy system dominated by new and renewable energy in the second half of the 21 st century as well as finally achieving the CO2 zero-emission.

Energy dissipation of cavity expansion based on generalized non-linear failure criterion under high stresses

Based on the compression mechanism for analyzing the cavity expansion problem in soil under high stresses,generalized non-linear failure criterion and large strain and energy conservation in plastic region during the cavity expanding were adopted.The energy conservation equation was established and the limited pressure of cavity expansion under high stresses was given based on the energy dissipation analysis method,in which the energy generated from cavity expansion is absorbed by the volume change and shear strain caused in soil.The factors of large strain and dilatation were considered by the proposed method.The analysis shows that the limited pressure is determined by failure criterion,stress state,large deformation characteristic,dilatation and strength of soil.It is shown from the comparison that the results with the proposed method approximate to those of the in-situ method.The cavity expansion pressure first decreases and then increases nonlinearly with both of shear modulus and dilatation increasing.

Sources and significance of variation in basal,summit and maximal metabolic rates in birds

The rates at which birds use energy may have profound effects on fitness, thereby influencing physiology, behavior, ecology and evolution. Comparisons of standardized metabolic rates （e.g., lower and upper limits of metabolic power output） present a method for elucidating the effects of ecological and evolutionary factors on the interface between physiology and life history in birds. In this paper we review variation in avian metabolic rates [basal metabolic rate （BMR; minimum normothermic metabolic rate）, summit metabolic rate （Msum; maximal thermoregulatory metabolic rate）, and maximal metabolic rate （MMR; maximal exercise metabolic rate）], the factors associated with this variation, the evidence for functional links between these metabolic traits, and the ecological and evolutionary significance of avian metabolic diversity. Both lower and upper limits to metabolic power production are phenotypically flexible traits, and vary in association with numerous ecological and evolutionary factors. For both inter- and intraspecific comparisons, lower and upper limits to metabolic power production are generally upregulated in response to energetically demanding conditions and downregulated when energetic demands are relaxed, or under conditions of energetic scarcity. Positive correlations have been documented between BMR, Msum and MMR in some, but not all studies on birds, providing partial support for the idea of a functional link between lower and upper limits to metabolic power production, but more intraspecific studies are needed to determine the robustness of this conclusion. Correlations between BMR and field metabolic rate （or daily energy expenditure） in birds are variable, suggesting that the linkage between these traits is subject to behavioral adjustment, and studies of the relationship between field and maximal metabolic rates are lacking. Our understanding of avian metabolic diversity would benefit from future studies of： （1） the functional and mechanistic links between lower and upper limits of metabolic power output; （2） the environmental and ecological cues driving phenotypically flexible metabolic responses, and how responses to such cues might impact population responses to climate change; （3） the shapes of metabolic reaction norms and their association with environmental variability; and （4） the relationship of metabolic variation to fitness, including studies of repeatability and heritability of minimum and maximum metabolic power output [Current Zoology 56 （6）： 741-758, 2010].

Roll-to-roll imprint for high precision grating manufacturing

In this paper,a novel roll-to-roll imprint process is proposed to fabricate gratings in large area. The key challenges in roll-to-roll imprint process,such as the roller mold preparation,imprint system,misalignment of imprint roller and backup roller,and also the imprint pressure,are investigated. Various gratings with different periods and profiles are obtained by the roll-to-roll process. To calibrate the measuring ability of the self-made grating by imprint,a calibration system is built with a dual-frequency laser interferometer. By the calibration,the self-made gratings can achieve ±4μm accuracy in 45mm measuring distance.

Response and energy dissipation of rock under stochastic stress waves

The response and energy dissipation of rock under stochastic stress waves were analyzed based on dynamic fracture criterion of brittle materials integrating with Fourier transform methods of spectral analysis. When the stochastic stress waves transmit through rocks, the frequency and energy ratio of harmonic components were calculated by analytical and discrete analysis methods. The stress waves in shale, malmstone and liparite were taken as examples to illustrate the proposed analysis methods. The results show the harder the rock, the less absorption of energy, the more the useless elastic waves transmitting through rock, and the narrower the cutoff frequency to fracture rock. When the whole stress energy doubles either by doubling the duration time or by increasing the amplitude of stress wave, ratio of the energy of elastic waves transmitting through rock to the whole stress energy (i.e. energy dissipation ratio) is decreased to 10%-15%. When doubling the duration time, the cutoff frequency to fracture rock remains constant. However, with the increase of the amplitude of stress wave, the cutoff frequency increases accordingly.

Ecological Footprint Dynamics of Yunnan, China

A fundamental element of sustainable development is that humans live within nature's biological capacity. Quantifying this, however, remains a significant challenge for which there are many emerging tools. The concept of the Ecological Footprint is one such accounting tool for comprehensive assessment of the status of sustainable development, based on integration of resource consumption and land capacity, reflecting the human impact on the environment. A region's development is defined as unsustainable when the Ecological Footprint surpasses the biological capacity. In this paper, the Ecological Footprint concept was applied in assessing the development of Yunnan Province, China in a period between 1988 and 2006. The results showed that the Ecological Footprint per capita in Yunnan rose from 0.854 gha in 1988 to 2.11 gha in 2006. Ecological deficit, defined as when the human demand on the land surpasses the regions biological productive capacity, emerged in 1991 and quickly increased from 0.02 gha in 1991 to 1.05 gha in 2006. The increase in the ecological deficit is primarily a result of the rapid increase in population and consumption level. To achieve sustainable development in Yunnan, production and consumption rates need to be modified.

Zero steady-states electrical energy consumption clutch system

A new clutch configuration with dual diaphragm spring is proposed. It is proper designed for electric and hybrid powertrain system. With this design, the clutch engagement is controlled by current in electrornagnet coil. For special characteristic of dual diaphragm spring, the clutch does not consume energy in steady state after engaging or disengaging. To validate the feasibility of this design, author builds the mathematical model and imports it into MATLAB Simulink. The simulation shows the behavior of clutch in different control strategies.

An Approach towards Eco-labeling of Compressed Air Filters Based on Carbon Footprint

Compressed air--a major industrial energy carrier, its filters are used to reach the required cleanliness level of compressed air. These filters, however, introduce a pressure drop which results in a loss of energy. It is shown that over the life cycle of a compressed air filter, the pressure drop dominates the total energy consumption and subsequently, the carbon footprint. From an economic as well as ecologic point of view, a reduction of the pressure drop is hence of utmost importance. Based on this finding and structuring, the wide range of applications and operational parameters, a pragmatic and technically feasible eco-labeling system for compressed air filters was developed as a decision supporting tool. Using this tool, procurement managers as well as the process engineers and environmental officers are able to steer the selection of suitable compressed air filters. The approach has been proposed to and discussed with various representatives of the compressed air filter industry nevertheless there is probably a long way to go to establish such a labeling procedure in industry.

GIS for Operative Support

GIS （geographic information systems） is often used for planning purposes in forestry. This is mainly used to give directives for the operators to cut the trees. And nowadays, it is also used for marking of areas with high environmental values where considerations should be made. The minor used techniques is to incorporate soil information maps as an overlay to give information to forest machine operators where less good trafficability is to be expected, especially after a heavy rain. By marking areas with bad bearing capacity, the operators may save both time and money, and do not bog down with the machine. When the soils bearing capacity is less than 0.7 MPa and the ground pressure of the machine is more than 80 kPa, either smaller machines must be used or bogey tracks should be used to decrease the risk for getting stuck or causing severe rutting. By choosing good types of bogey tracks both rutting and fuel consumption will be decreased for the health of forest land and the contractor.

Energy Dissipation Within the Wave Run-Up at Stepped Revetments

To understand the processes and energy dissipation performance caused by turbulence during the wave run-up over a stepped revetment,hydraulic model tests with steady flow conditions are conducted and correlated with unsteady flow conditions of the wave run-up within a short time frame.Under irregular waves,the run-up reduction over a stepped revetment is dependent on the Iribarren number and decreases for decreasing Iribarren numbers.Velocity gradients are found to be similar in a steady and unsteady flow regime near the pseudo-bottom.

Energy Scheduling with Roles Dormant Cells （SRDC） in wireless sensor network （WSN）

Power consumption is the main challenge to expand the wireless sensor network, since the active nodes are vulnerable to energy consumption. This paper proposes the tasks scheduling and distribution energy management mechanism of roles dormant cells to curb excessive consumption of energy in the performance of duplicated tasks. Experimental results verify the proposal existing low energy adaptive clustering hierarchy （LEACH） protocol with SRDC approach establishes a low-energy communication structure and increases the lifetime.

Load Management Scheme Using Air Conditioning Electric Power Consumption and Photovoltaic Power System Generation

In the last few decades, in the world and also in the European Union, considerable resources had been invested in the rapid development of renewable energy sources and distributed generation in general. At the same time, power consumption is continuously increasing, and consumers are becoming more complex, which ultimately requires new investments in the distribution network. Concept of smart grids is generally accepted as a possible solution. Smart grid is a concept with many elements, where monitoring and control of every element in the chain of production, transmission, distribution and final consumption enable much more efficient delivery and use of electricity. One of the elements of smart grid efficiency is the ability of real-time demand-supply balancing. This balancing is carried out by monitoring of consumption and redistribution of electricity among individual end users, according to their needs. The aim of this paper is creating algorithm for real-time load management using power measurements. Algorithm for real-time load management at the ETFOS （Faculty of Electrical Engineering in Osijek）, Croatia is created based on measurements of photovoltaic power plant production, the power consumption of air conditioning system and the faculty building total electricity consumption. Expected result of real-time re-dispatching of air conditioners consumption, depending on the level of electricity production in photovoltaic power plant is decreasing peak demand of the faculty.

An effective thermodynamic transformation analysis method for actual irreversible cycle

An effective thermodynamic transformation analysis method was proposed in this study. According to the phenomenon of ex- ergy consumption always coupling with heat transfer process, the effective thermodynamic temperatures were defined, then the actual power cycle or refrigeration/heat pump cycle was transformed into the equivalent reversible Carnot or reverse Carnot cycles for thermodynamic analysis. The derived effective thermodynamic temperature of the hot reservoir of the equivalent reverse Camot cycle is the basis of the proposed method. The combined diagram of TR-h and TR-q was adopted for the analy- sis of the system performance and the exergy consumption, which takes advantage of the visual expression of the heat/work exchange and the enthalpy change, and is convenient for the calculation of the coefficient of performance and exergy con- sumptions. Take a heat pump water heater with refrigerant of R22 for example, the proposed method was systematically intro- duced, and the fitting formulas of the effective thermodynamic temperatures were given as demonstration. The results show that the proposed method has advantage and well application foreground in the performance simulation and estimation under the variable working conditions.

Development of performance and combustion system of Atkinson cycle internal combustion engine

The application of hybrid vehicle is a practical technical solution to the energy shortage and the environmental pollution.The internal combustion engine(ICE)plays a key role in the development of the hybrid vehicle.Based on the requirements of the hybrid vehicle and the characteristic of Atkinson cycle,a set of designing methods for the Atkinson cycle gasoline engine is presented through the analysis of the optimized matching for the compression ratio,valve timing and the combustion chamber.The designing method has been verified by the bench test and the results show that the fuel consumption can be improved by12%–15%with the reduction of the low speed torque by 10%,and the low fuel consumption region in the fuel map extends significantly with the rated power almost keeping constant.It may be of great reference for the development of hybrid vehicle technology in China.

Fuel-optimal trajectory design using solar electric propulsion under power constraints and performance degradation

The fuel-optimal transfer trajectories using solar electric propulsion are designed considering the power constraints and solar array performance degradation.Three different performance degradation models including linear,positive and negative exponential degradations are used in the analysis of three typical rendezvous missions including Apophis,Venus and Ceres,respectively.The optimal control problem is formulated using the calculus of variations and Pontryagin’s maximum principle,which leads to a bang-bang control that is solved by indirect method combined with a homotopic technique.In demonstrating the effects of the power constraints and solar array performance degradation on the power budget and fuel consumption,the time histories of the power profile and the fuel consumptions are compared for the three missions.This study indicates that it is necessary to consider the power constraints and solar array performance degradation for the SEP-based low-thrust trajectory design,espacially for long-duration outbound flights.