A new type of liquid desiccant water chiller for applications on air-conditioning and refrigeration is introduced.The system can be driven by low-grade heat sources with temperatures of 60 to 80 ℃,which can be easily...A new type of liquid desiccant water chiller for applications on air-conditioning and refrigeration is introduced.The system can be driven by low-grade heat sources with temperatures of 60 to 80 ℃,which can be easily obtained by a flat plat solar collector,waste heat,etc.A numerical model is developed to study the system performance.The effects of different parameters on performance are discussed,including evaporating temperature,regenerating temperature,ambient condition,and mass flow rates of closed moist air and regenerating air.The results show that an acceptable performance of a cooling capacity of 2.5 kW and a coefficient of performance of 0.37 can be achieved in a reference case.The regenerating temperature and the humidity ratios of ambient air are two main factors affecting system performance,while the temperature of ambient air functions less.In addition,the mass flow rate of regenerating air and closed moist air should be carefully determined for economical operation.展开更多
As one of the key technologies for the fifth generation(5G) wireless networks,device-to-device(D2D) communications allow user equipment(UE) in close proximity to communicate with each other directly.Forwarded by a rel...As one of the key technologies for the fifth generation(5G) wireless networks,device-to-device(D2D) communications allow user equipment(UE) in close proximity to communicate with each other directly.Forwarded by a relay,the relay-aided D2D(RA-D2D) communications can not only be applied to communications in much longer distance but also achieve a high quality of service(Qo S) .In this paper,we first propose a two-layer system model allowing RA-D2 D links to underlay traditional cellular uplinks.Then we maximize the energy efficiency of the RA-D2 D link while satisfying the minimum data-rate of the cellular link.The optimal transmit power at both D2 D transmitter and D2 D relay sides is obtained by transforming the nonlinear fractional programming into a nonlinear parameter programming.Simulation results show that our proposed power allocation method is more energy efficient than the existing works,and the proposed RA-D2 D scheme outperformed direct D2 D scheme when the distance between two D2 D users is longer.展开更多
Compared with ordinary commercial products, housing has many special characteristics including the multi-function characteristic. How to evaluate the multi-functional nature of housing is very useful in both theory an...Compared with ordinary commercial products, housing has many special characteristics including the multi-function characteristic. How to evaluate the multi-functional nature of housing is very useful in both theory and in application, yet it is often ignored in China. This paper introduces an approach to estimate the multicriteria function of housing using multiattribute utility theory (MAUT) based on consumers’ ordinal multicriteria preferences as determined via questionnaires. When compared with the classic framework in which MAUT is applied, this approach needs less prior information and subjective comparisons and thus can allay many of the operational difficulties involved in assessment. Some potential applications to the China housing market are also discussed.展开更多
The control strategy is one of the most important renewable technology,and an increasing number of multi-MW wind turbines are being developed with a variable speed-variable pitch(VS-VP)technology.The main objective of...The control strategy is one of the most important renewable technology,and an increasing number of multi-MW wind turbines are being developed with a variable speed-variable pitch(VS-VP)technology.The main objective of adopting a VS-VP technology is to improve the fast response speed and capture maximum energy.But the power generated by wind turbine changes rapidly because of the continuous fluctuation of wind speed and direction.At the same time,wind energy conversion systems are of high order,time delays and strong nonlinear characteristics because of many uncertain factors.Based on analyzing the all dynamic processes of wind turbine,a kind of layered multi-mode optimal control strategy is presented which is that three control strategies:bang-bang,fuzzy and adaptive proportional integral derivative(PID)are adopted according to different stages and expected performance of wind turbine to capture optimum wind power,compensate the nonlinearity and improve the wind turbine performance at low,rated and high wind speed.展开更多
In the cloud data centers,how to map virtual machines(VMs) on physical machines(PMs) to reduce the energy consumption is becoming one of the major issues,and the existing VM scheduling schemes are mostly to reduce ene...In the cloud data centers,how to map virtual machines(VMs) on physical machines(PMs) to reduce the energy consumption is becoming one of the major issues,and the existing VM scheduling schemes are mostly to reduce energy consumption by optimizing the utilization of physical servers or network elements.However,the aggressive consolidation of these resources may lead to network performance degradation.In view of this,this paper proposes a two-stage VM scheduling scheme:(1) We propose a static VM placement scheme to minimize the number of activating PMs and network elements to reduce the energy consumption;(2) In the premise of minimizing the migration costs,we propose a dynamic VM migration scheme to minimize the maximum link utilization to improve the network performance.This scheme makes a tradeoff between energy efficiency and network performance.We design a new twostage heuristic algorithm for a solution,and the simulations show that our solution achieves good results.展开更多
Energy method for the vibration of two types of cylindrical shells,namely thin-walled homogeneous isotropic and manifold layered isotropic cylindrical shells under uniform external lateral pressure is presented.The st...Energy method for the vibration of two types of cylindrical shells,namely thin-walled homogeneous isotropic and manifold layered isotropic cylindrical shells under uniform external lateral pressure is presented.The study is carried out based on strain-displacement relationship from Love's shell theory with beam functions as axial modal function.A manifold layered cylindrical shell configuration is formed by three layers of isotropic material where the inner and outer layers are stainless steel and the middle layer is aluminum.The homogeneous cylindrical shell is made-up of isotropic one layer with stainless steel.The governing equations with uniform external lateral pressure for homogeneous isotropic and manifold layered isotropic cylindrical shells are obtained using energy functional by the Lagrangian function with Rayleigh-Ritz method.The boundary conditions that are presented at the end conditions of the cylindrical shell are simply supported-simply supported,clamped-clamped and free-free.The influences of uniform external lateral pressure and symmetrical boundary conditions on the natural frequency characteristics for both homogeneous and manifold layered isotropic cylindrical shells are examined.For all boundary conditions considered,the natural frequency of both cylindrical shells with symmetric uniform lateral pressure increases as h/R ratio increases and those considering natural frequency of the both cylindrical shells with symmetric uniform lateral pressure decrease as L/R ratio increases.展开更多
In this paper, we developed performance assessment criteria to evaluate effects of compliance to ISPS Code's requirements on port/terminal operation in Nigeria. The primary data for the study were obtained from copie...In this paper, we developed performance assessment criteria to evaluate effects of compliance to ISPS Code's requirements on port/terminal operation in Nigeria. The primary data for the study were obtained from copies ofsurvey questionnaires administered to random sample of port users stratified by areas of specialisation. Hypotheses governing this study were based on the premise that additional port facilities provided and security measures adopted in compliance to ISPS code's requirements would have positive spillover effects on port operations. Evidence from data analysis indicated that compliance to ISPS code had positive effects on performance of operational performance of Nigeria ports. Similar effects were also observed inport users' satisfaction and profitability. The paper contributes by providing decision support framework for ports and terminals. monitoring and gauging outcomes of ISPS code administration in展开更多
Vehicle suspension design includes a number of compromises to provide good leveling of stability and ride comfort. Optimization of off-road vehicle suspension system is one of the most effective methods, which could c...Vehicle suspension design includes a number of compromises to provide good leveling of stability and ride comfort. Optimization of off-road vehicle suspension system is one of the most effective methods, which could considerably enhance the vehicle stability and controllability. In this work, a comprehensive optimization of an off-read vehicle suspension system model was carried out using software ADAMS. The geometric parameters of suspension system were optimized using genetic algorithm (GA) in a way that ride comfort, handling and stability of vehicle were improved. The results of optimized suspension system and variations of geometric parameters due to road roughness and different steering angles were presented in ADAMS and the results of optimized and conventional suspension systems during various driving maneuvers were compared. The simulation results indicate that the camber angle variations decrease by the optimized suspension system, resulting in improved handling and ride comfort characteristics.展开更多
Abstract: Nowadays energy saving and environmental protection are crucial issues in the international society. One of the best solutions for both issues is to improve energy efficiency. To improve energy efficiency, ...Abstract: Nowadays energy saving and environmental protection are crucial issues in the international society. One of the best solutions for both issues is to improve energy efficiency. To improve energy efficiency, it is commonly recognized by both standards and energy sectors that Minimum Energy Performance Standards (MEPS) could play an important role . China and the USA, the top two energy consumption countries in the world, both have adopted MEPS program to address the problem of energy conservation and environmental protection. This paper analyzes and compares the two countries' MEPS programs from a historical and legal context, examining the role of different stakeholders in the process,the process, the outcomes by standards,and then makes some recommendations for both sides.展开更多
Solid waste management is a serious problem over the world. Therefore, reduction, re-use and recycling of waste have become major issues in recent days. Gypsum waste plasterboard is considered one example of these was...Solid waste management is a serious problem over the world. Therefore, reduction, re-use and recycling of waste have become major issues in recent days. Gypsum waste plasterboard is considered one example of these waste materials. This study evaluates the use of recycled bassanite, which is derived from gypsum waste plasterboard, to enhance the performance of two types of cohesion-less soil. Recycled bassanite was utilized as a stabilizing agent to improve both compressive and splitting strengths of the tested soil. The effect of bassanite content, soil type, water content and curing time were investigated to explore the behavior of treated soil with recycled bassanite. Test results showed that increase of bassanite content is associated with increase in optimal moisture content, while no significant increase in the dry unit weight was observed. Both compressive and splitting tensile strengths enhanced with the additives of recycled bassanite. The increase of bassanite content had a more significant effect on the compressive strength compared with the effect on tensile strength. The use of recycled bassanite to enhance the strength of sandy soil had a more significant effect compared with silty soil. The effect of curing time on the strength of treated samples was more significant in early curing ages compared with late curing ages. The strength decreased significantly in case of stabilized samples prepared with water content at the wet-side of the compaction curve. However, insignificant decrease in the strength of the stabilized sample was detected with moisture content at the dry-side of compaction curve. This research meets the challenges of our society to reduce the quantities of gypsum wastes, producing useful material from waste materials that will help to a sustainable society.展开更多
An 8-week feeding experiment was conducted in an indoor recirculation seawater system to investigate the effects of partial replacement of dietary fishmeal with proteins from five sources on the growth performance and...An 8-week feeding experiment was conducted in an indoor recirculation seawater system to investigate the effects of partial replacement of dietary fishmeal with proteins from five sources on the growth performance and feed utilization of Sebastes schlegeli. Six isonitrogenous and isoenergetic diets were formulated using fishmeal(FM, the control) as sole protein source, or proteins from five sources including poultry by-product meal(PBM), meat and bone meal(MBM), soybean meal(SBM), cottonseed meal(CSM) and canola meal(CNM). Fifteen percent of the crude protein provided by fish meal was replaced, respectively. The results showed that the differences in specific growth rate(SGR) and survival rate(SR) among fish fed PBM, MBM, SBM, CSM and whole FM diets were not significant. However, SGR and SR of fish fed CNM diet was significantly lower than that of other treatments. Feeding rate, feed conversion, nutrient retention showed similar patterns to that of growth. Fish fed CSM and CNM showed significantly lower apparent digestibility coefficient(ADC) of dry matter and gross energy than those fed others while fish fed CNM showed lower ADC of crude protein than those fed others(P<0.05). These results suggested that it was feasible to substitute 15% dietary protein provided by fishmeal with PBM, MBM, SBM and CSM, respectively, but not with CNM as the replacement with CNM reduced fish growth and feed utilization.展开更多
The effects of root oxidization ability and P fertilization on As mobility in soils, and subsequently As uptake, translocation and speciation in rice plants were investigated. Results show that root oxidation signific...The effects of root oxidization ability and P fertilization on As mobility in soils, and subsequently As uptake, translocation and speciation in rice plants were investigated. Results show that root oxidation significantly influences As mobility in rhizoshphere.Genotype TD71 with higher radial oxygen loss(ROL) induces more Fe plaque formation and sequesters more As and P in iron plaque and rhizoshphere soil, leading to the reduction of As accumulation in rice plants. Additionally, P addition mobilizes As in soil solution, and increases As accumulation in rice plants. Arsenic speciation results show that the majority of As species in husks detected is inorganic As, accounting for 82%-93% of the total As, while in grains the majority of As is inorganic As and dimethyl arsenic(DMA), with DMA accounting for 33%-64% of the total As. The fraction of inorganic As decreases while fraction of DMA increases, with increasing As and P concentrations. The study further elucidates the mechanisms involved in effects of ROL on As tolerance and accumulation in rice.展开更多
A plot of 24 m × 10 m under fallow management after several years of cultivation to maize (Zea mays) was planted to tea (Camellia sinensis) cuttings at 1.0 m ×0.6 m and treated with or without fertilizer...A plot of 24 m × 10 m under fallow management after several years of cultivation to maize (Zea mays) was planted to tea (Camellia sinensis) cuttings at 1.0 m ×0.6 m and treated with or without fertilizer. The tea cuttings were applied NPK 25:5:5 (reference fertilizer), cocoa husk, cow-dung, tea fluff and poultry droppings as manures, mixtures of the manures with urea in 3:1 ratio of N contents as organomineral and the control (no fertilizer), monitored for growth performance for two years at Kusuku (6°50'N; 11 °07'E), Nigeria. The organic based fertilizers generally outperformed NPK 25:5:5 and control in all the growth parameters. Organominerals resulted in an overall higher plant height, girth, number of leaves and branches compared to the manures in the first year of establishment, while the values were higher for manure treated plants in the second year. This trend was attributed to quicker release of nutrient by the organominerals in the first year, while the manures had undergone adequate decomposition for sufficient nutrient release to the advantage of the tea plants in the second year. However, comparative cost analysis showed that organominerals were more economical to achieve optimum tea production at minimum cost in the locality.展开更多
This sixty-day study was performed to determine the effects of short-term starvation and refeeding cycles on growth, feeding performances and body composition of rainbow trout (Oncorhynchus mykiss). Three hundred tr...This sixty-day study was performed to determine the effects of short-term starvation and refeeding cycles on growth, feeding performances and body composition of rainbow trout (Oncorhynchus mykiss). Three hundred trout fingerlings with an average initial weight of 17.54-0.06 g were randomly distributed in 15 circular fiberglass tanks. The fish were exposed to 5 different feeding regimes; control: continuously fed twice daily to apparent satiation; T1: starved for 1 day and re-fed for 2 days; T2: starved for 1 day and re-fed for 4 days; T3: starved for 3 days and re-fed for 12 days; T4: starved for 4 days and re-fed for 16 days. At the end of the experiment, growth performance, feed utilization, whole body ash and moisture contents were not significantly (P〉0.05) different among the treatments. However, whole body protein content in T3 was significantly higher than other treatments (P〈0.05). A significant difference in whole body fat content was observed between T3 and the control group at the end of the experiment (P〈0.05). In conclusion this experiment suggests that feeding schedules involving starvation (1-4 days) and re-feeding cycles are a promising feed management tool for rainbow trout culture.展开更多
The present paper seeks to investigate the extent to which digital activism plays a role in political activism in Morocco through the intersection between women and young activists movement and the social media. By do...The present paper seeks to investigate the extent to which digital activism plays a role in political activism in Morocco through the intersection between women and young activists movement and the social media. By doing so the author argues that while facebook and the Moroccan political arena are Male dominated public areas, young female activists have emerged as prominent leaders in both spaces. The author will more particularly explain why female and youth activists are important in the current state of Moroccan politics. Next, the author provides a discussion of the February 20th Movement, and the movement's utilization of Facebook. It will show that young female activists involved in the February 20th Movement have used Facebook in unique and creative ways to further the Movement.展开更多
Land property in the post socialist countries was rebuilt in the beginning of the 1990s. The process went in different way in all of the post-socialist countries. The result of the privatization of agricultural land w...Land property in the post socialist countries was rebuilt in the beginning of the 1990s. The process went in different way in all of the post-socialist countries. The result of the privatization of agricultural land was a fragmented, direct or indirect smallholder ownership structure in most of the new member states of the EU. The land, partly or totally was given back to the owners and inheritors of land reforms following the war. It means that considerable proportion of the land is cultivated by tenants, the fragmented estate structure decreases the efficiency and the increasing rental fees further destroy the profitability and competitiveness of farming. Regarding to the competitiveness of agriculture, Poland showed a developing tendency after the accession, but Hungary suffers from serious problems. Applying descriptive statistics between the changes of land use and land ownership during the research relation analysis, emphasizing the effect in competitiveness of the land price and a land rent, the paper tries to identify the main differences and similarities in land use and property structure, and their effects on the agricultural competitiveness based on the FADN data base, since 2004-2007.展开更多
This paper briefly introduces the application of new materials in sports and effect on sports performance, points out that development of competitive sports in the process, must pay attention to the development and ut...This paper briefly introduces the application of new materials in sports and effect on sports performance, points out that development of competitive sports in the process, must pay attention to the development and utilization of new materials, development.展开更多
HVFA (high-volume fly ash) concrete could be a sustainable way for by-product utilization to conserve natural resources and protect environment. HVFA concrete can play the role of a high-performance material that ma...HVFA (high-volume fly ash) concrete could be a sustainable way for by-product utilization to conserve natural resources and protect environment. HVFA concrete can play the role of a high-performance material that may be comparable to the conventional Portland cement concrete. The results of the research programme concerning the relationships between the composition of concrete (w/b ratio, fly ash content and type of cement) and their physical and mechanical properties are presented and discussed in the paper. It is found that the introduction of high-volume fly ash into concrete has caused a decrease in compressive strength at the early age of storage. The significant increase in strength was observed between 28 days and 90 days of curing. The high-volume fly ash concretes were characterized with lower water absorbability and sorptivity than control concrete.展开更多
Small cells have been regarded as an appealing technique to boost resource reuse ratio. On the other hand, their large-scale and self-organised tendency would complicate the interference environment of mobile networks...Small cells have been regarded as an appealing technique to boost resource reuse ratio. On the other hand, their large-scale and self-organised tendency would complicate the interference environment of mobile networks. Meanwhile, traffic class is booming in recent years, which leads to higher demand for net- work designers on Quality of Service (QoS) provision, and therefore users' diverse re- quirements may not be guaranteed in sucff'an interference limited scenario. To maximise the number of users with QoS demands as well as resource reuse ratio, we formulate the resource allocation problem into a multi-objective l0 norm form. It is shown to be NP hard, and an iterative method is employed to approach the optimal solution. Because of its limit of being not adaptive to large-scale networks, we also design a heuristic method based on chordal graph, which, however, could result in per- formance loss when the size of networks is small. Finally, by combining these two meth- ods, we devise a hybrid algorithm such that the allocation performs both efficiently and effectively. Simulation results illustrate the performance of our proposed methods in terms of outage probability and resource reuse ratio.展开更多
基金The National Natural Science Foundation of China(No.50976021)the National Key Technology R&D Program of China during the 11th Five-Year Plan Period(No.2007BA000875)
文摘A new type of liquid desiccant water chiller for applications on air-conditioning and refrigeration is introduced.The system can be driven by low-grade heat sources with temperatures of 60 to 80 ℃,which can be easily obtained by a flat plat solar collector,waste heat,etc.A numerical model is developed to study the system performance.The effects of different parameters on performance are discussed,including evaporating temperature,regenerating temperature,ambient condition,and mass flow rates of closed moist air and regenerating air.The results show that an acceptable performance of a cooling capacity of 2.5 kW and a coefficient of performance of 0.37 can be achieved in a reference case.The regenerating temperature and the humidity ratios of ambient air are two main factors affecting system performance,while the temperature of ambient air functions less.In addition,the mass flow rate of regenerating air and closed moist air should be carefully determined for economical operation.
基金supported by the ZTE Corp under Grant CON1412150018the Natural Science Foundation of China under Grant 61572389 and 61471361
文摘As one of the key technologies for the fifth generation(5G) wireless networks,device-to-device(D2D) communications allow user equipment(UE) in close proximity to communicate with each other directly.Forwarded by a relay,the relay-aided D2D(RA-D2D) communications can not only be applied to communications in much longer distance but also achieve a high quality of service(Qo S) .In this paper,we first propose a two-layer system model allowing RA-D2 D links to underlay traditional cellular uplinks.Then we maximize the energy efficiency of the RA-D2 D link while satisfying the minimum data-rate of the cellular link.The optimal transmit power at both D2 D transmitter and D2 D relay sides is obtained by transforming the nonlinear fractional programming into a nonlinear parameter programming.Simulation results show that our proposed power allocation method is more energy efficient than the existing works,and the proposed RA-D2 D scheme outperformed direct D2 D scheme when the distance between two D2 D users is longer.
文摘Compared with ordinary commercial products, housing has many special characteristics including the multi-function characteristic. How to evaluate the multi-functional nature of housing is very useful in both theory and in application, yet it is often ignored in China. This paper introduces an approach to estimate the multicriteria function of housing using multiattribute utility theory (MAUT) based on consumers’ ordinal multicriteria preferences as determined via questionnaires. When compared with the classic framework in which MAUT is applied, this approach needs less prior information and subjective comparisons and thus can allay many of the operational difficulties involved in assessment. Some potential applications to the China housing market are also discussed.
基金Science & Technology Development Foundation of Shanghai,China(No.062158017)Postdoctoral Foundation of Shanghai,China(No.05R214133)Postdoctoral Foundation of China(No.2005038435)
文摘The control strategy is one of the most important renewable technology,and an increasing number of multi-MW wind turbines are being developed with a variable speed-variable pitch(VS-VP)technology.The main objective of adopting a VS-VP technology is to improve the fast response speed and capture maximum energy.But the power generated by wind turbine changes rapidly because of the continuous fluctuation of wind speed and direction.At the same time,wind energy conversion systems are of high order,time delays and strong nonlinear characteristics because of many uncertain factors.Based on analyzing the all dynamic processes of wind turbine,a kind of layered multi-mode optimal control strategy is presented which is that three control strategies:bang-bang,fuzzy and adaptive proportional integral derivative(PID)are adopted according to different stages and expected performance of wind turbine to capture optimum wind power,compensate the nonlinearity and improve the wind turbine performance at low,rated and high wind speed.
基金supported by the National Natural Science Foundation of China(61002011)the National High Technology Research and Development Program of China(863 Program)(2013AA013303)+1 种基金the Fundamental Research Funds for the Central Universities(2013RC1104)the Open Fund of the State Key Laboratory of Software Development Environment(SKLSDE-2009KF-2-08)
文摘In the cloud data centers,how to map virtual machines(VMs) on physical machines(PMs) to reduce the energy consumption is becoming one of the major issues,and the existing VM scheduling schemes are mostly to reduce energy consumption by optimizing the utilization of physical servers or network elements.However,the aggressive consolidation of these resources may lead to network performance degradation.In view of this,this paper proposes a two-stage VM scheduling scheme:(1) We propose a static VM placement scheme to minimize the number of activating PMs and network elements to reduce the energy consumption;(2) In the premise of minimizing the migration costs,we propose a dynamic VM migration scheme to minimize the maximum link utilization to improve the network performance.This scheme makes a tradeoff between energy efficiency and network performance.We design a new twostage heuristic algorithm for a solution,and the simulations show that our solution achieves good results.
文摘Energy method for the vibration of two types of cylindrical shells,namely thin-walled homogeneous isotropic and manifold layered isotropic cylindrical shells under uniform external lateral pressure is presented.The study is carried out based on strain-displacement relationship from Love's shell theory with beam functions as axial modal function.A manifold layered cylindrical shell configuration is formed by three layers of isotropic material where the inner and outer layers are stainless steel and the middle layer is aluminum.The homogeneous cylindrical shell is made-up of isotropic one layer with stainless steel.The governing equations with uniform external lateral pressure for homogeneous isotropic and manifold layered isotropic cylindrical shells are obtained using energy functional by the Lagrangian function with Rayleigh-Ritz method.The boundary conditions that are presented at the end conditions of the cylindrical shell are simply supported-simply supported,clamped-clamped and free-free.The influences of uniform external lateral pressure and symmetrical boundary conditions on the natural frequency characteristics for both homogeneous and manifold layered isotropic cylindrical shells are examined.For all boundary conditions considered,the natural frequency of both cylindrical shells with symmetric uniform lateral pressure increases as h/R ratio increases and those considering natural frequency of the both cylindrical shells with symmetric uniform lateral pressure decrease as L/R ratio increases.
文摘In this paper, we developed performance assessment criteria to evaluate effects of compliance to ISPS Code's requirements on port/terminal operation in Nigeria. The primary data for the study were obtained from copies ofsurvey questionnaires administered to random sample of port users stratified by areas of specialisation. Hypotheses governing this study were based on the premise that additional port facilities provided and security measures adopted in compliance to ISPS code's requirements would have positive spillover effects on port operations. Evidence from data analysis indicated that compliance to ISPS code had positive effects on performance of operational performance of Nigeria ports. Similar effects were also observed inport users' satisfaction and profitability. The paper contributes by providing decision support framework for ports and terminals. monitoring and gauging outcomes of ISPS code administration in
文摘Vehicle suspension design includes a number of compromises to provide good leveling of stability and ride comfort. Optimization of off-road vehicle suspension system is one of the most effective methods, which could considerably enhance the vehicle stability and controllability. In this work, a comprehensive optimization of an off-read vehicle suspension system model was carried out using software ADAMS. The geometric parameters of suspension system were optimized using genetic algorithm (GA) in a way that ride comfort, handling and stability of vehicle were improved. The results of optimized suspension system and variations of geometric parameters due to road roughness and different steering angles were presented in ADAMS and the results of optimized and conventional suspension systems during various driving maneuvers were compared. The simulation results indicate that the camber angle variations decrease by the optimized suspension system, resulting in improved handling and ride comfort characteristics.
文摘Abstract: Nowadays energy saving and environmental protection are crucial issues in the international society. One of the best solutions for both issues is to improve energy efficiency. To improve energy efficiency, it is commonly recognized by both standards and energy sectors that Minimum Energy Performance Standards (MEPS) could play an important role . China and the USA, the top two energy consumption countries in the world, both have adopted MEPS program to address the problem of energy conservation and environmental protection. This paper analyzes and compares the two countries' MEPS programs from a historical and legal context, examining the role of different stakeholders in the process,the process, the outcomes by standards,and then makes some recommendations for both sides.
文摘Solid waste management is a serious problem over the world. Therefore, reduction, re-use and recycling of waste have become major issues in recent days. Gypsum waste plasterboard is considered one example of these waste materials. This study evaluates the use of recycled bassanite, which is derived from gypsum waste plasterboard, to enhance the performance of two types of cohesion-less soil. Recycled bassanite was utilized as a stabilizing agent to improve both compressive and splitting strengths of the tested soil. The effect of bassanite content, soil type, water content and curing time were investigated to explore the behavior of treated soil with recycled bassanite. Test results showed that increase of bassanite content is associated with increase in optimal moisture content, while no significant increase in the dry unit weight was observed. Both compressive and splitting tensile strengths enhanced with the additives of recycled bassanite. The increase of bassanite content had a more significant effect on the compressive strength compared with the effect on tensile strength. The use of recycled bassanite to enhance the strength of sandy soil had a more significant effect compared with silty soil. The effect of curing time on the strength of treated samples was more significant in early curing ages compared with late curing ages. The strength decreased significantly in case of stabilized samples prepared with water content at the wet-side of the compaction curve. However, insignificant decrease in the strength of the stabilized sample was detected with moisture content at the dry-side of compaction curve. This research meets the challenges of our society to reduce the quantities of gypsum wastes, producing useful material from waste materials that will help to a sustainable society.
基金funded by National Key Basic Research Program (2009CB118702)partly by the Knowledge Innovation Program of the Chinese Academy of Sciences
文摘An 8-week feeding experiment was conducted in an indoor recirculation seawater system to investigate the effects of partial replacement of dietary fishmeal with proteins from five sources on the growth performance and feed utilization of Sebastes schlegeli. Six isonitrogenous and isoenergetic diets were formulated using fishmeal(FM, the control) as sole protein source, or proteins from five sources including poultry by-product meal(PBM), meat and bone meal(MBM), soybean meal(SBM), cottonseed meal(CSM) and canola meal(CNM). Fifteen percent of the crude protein provided by fish meal was replaced, respectively. The results showed that the differences in specific growth rate(SGR) and survival rate(SR) among fish fed PBM, MBM, SBM, CSM and whole FM diets were not significant. However, SGR and SR of fish fed CNM diet was significantly lower than that of other treatments. Feeding rate, feed conversion, nutrient retention showed similar patterns to that of growth. Fish fed CSM and CNM showed significantly lower apparent digestibility coefficient(ADC) of dry matter and gross energy than those fed others while fish fed CNM showed lower ADC of crude protein than those fed others(P<0.05). These results suggested that it was feasible to substitute 15% dietary protein provided by fishmeal with PBM, MBM, SBM and CSM, respectively, but not with CNM as the replacement with CNM reduced fish growth and feed utilization.
基金Project(41201493)supported by the National Natural Science Foundation of ChinaProject(201109056)supported by Special Scientific Research of Environmental Protection for Public Welfare Industry,China
文摘The effects of root oxidization ability and P fertilization on As mobility in soils, and subsequently As uptake, translocation and speciation in rice plants were investigated. Results show that root oxidation significantly influences As mobility in rhizoshphere.Genotype TD71 with higher radial oxygen loss(ROL) induces more Fe plaque formation and sequesters more As and P in iron plaque and rhizoshphere soil, leading to the reduction of As accumulation in rice plants. Additionally, P addition mobilizes As in soil solution, and increases As accumulation in rice plants. Arsenic speciation results show that the majority of As species in husks detected is inorganic As, accounting for 82%-93% of the total As, while in grains the majority of As is inorganic As and dimethyl arsenic(DMA), with DMA accounting for 33%-64% of the total As. The fraction of inorganic As decreases while fraction of DMA increases, with increasing As and P concentrations. The study further elucidates the mechanisms involved in effects of ROL on As tolerance and accumulation in rice.
文摘A plot of 24 m × 10 m under fallow management after several years of cultivation to maize (Zea mays) was planted to tea (Camellia sinensis) cuttings at 1.0 m ×0.6 m and treated with or without fertilizer. The tea cuttings were applied NPK 25:5:5 (reference fertilizer), cocoa husk, cow-dung, tea fluff and poultry droppings as manures, mixtures of the manures with urea in 3:1 ratio of N contents as organomineral and the control (no fertilizer), monitored for growth performance for two years at Kusuku (6°50'N; 11 °07'E), Nigeria. The organic based fertilizers generally outperformed NPK 25:5:5 and control in all the growth parameters. Organominerals resulted in an overall higher plant height, girth, number of leaves and branches compared to the manures in the first year of establishment, while the values were higher for manure treated plants in the second year. This trend was attributed to quicker release of nutrient by the organominerals in the first year, while the manures had undergone adequate decomposition for sufficient nutrient release to the advantage of the tea plants in the second year. However, comparative cost analysis showed that organominerals were more economical to achieve optimum tea production at minimum cost in the locality.
文摘This sixty-day study was performed to determine the effects of short-term starvation and refeeding cycles on growth, feeding performances and body composition of rainbow trout (Oncorhynchus mykiss). Three hundred trout fingerlings with an average initial weight of 17.54-0.06 g were randomly distributed in 15 circular fiberglass tanks. The fish were exposed to 5 different feeding regimes; control: continuously fed twice daily to apparent satiation; T1: starved for 1 day and re-fed for 2 days; T2: starved for 1 day and re-fed for 4 days; T3: starved for 3 days and re-fed for 12 days; T4: starved for 4 days and re-fed for 16 days. At the end of the experiment, growth performance, feed utilization, whole body ash and moisture contents were not significantly (P〉0.05) different among the treatments. However, whole body protein content in T3 was significantly higher than other treatments (P〈0.05). A significant difference in whole body fat content was observed between T3 and the control group at the end of the experiment (P〈0.05). In conclusion this experiment suggests that feeding schedules involving starvation (1-4 days) and re-feeding cycles are a promising feed management tool for rainbow trout culture.
文摘The present paper seeks to investigate the extent to which digital activism plays a role in political activism in Morocco through the intersection between women and young activists movement and the social media. By doing so the author argues that while facebook and the Moroccan political arena are Male dominated public areas, young female activists have emerged as prominent leaders in both spaces. The author will more particularly explain why female and youth activists are important in the current state of Moroccan politics. Next, the author provides a discussion of the February 20th Movement, and the movement's utilization of Facebook. It will show that young female activists involved in the February 20th Movement have used Facebook in unique and creative ways to further the Movement.
文摘Land property in the post socialist countries was rebuilt in the beginning of the 1990s. The process went in different way in all of the post-socialist countries. The result of the privatization of agricultural land was a fragmented, direct or indirect smallholder ownership structure in most of the new member states of the EU. The land, partly or totally was given back to the owners and inheritors of land reforms following the war. It means that considerable proportion of the land is cultivated by tenants, the fragmented estate structure decreases the efficiency and the increasing rental fees further destroy the profitability and competitiveness of farming. Regarding to the competitiveness of agriculture, Poland showed a developing tendency after the accession, but Hungary suffers from serious problems. Applying descriptive statistics between the changes of land use and land ownership during the research relation analysis, emphasizing the effect in competitiveness of the land price and a land rent, the paper tries to identify the main differences and similarities in land use and property structure, and their effects on the agricultural competitiveness based on the FADN data base, since 2004-2007.
文摘This paper briefly introduces the application of new materials in sports and effect on sports performance, points out that development of competitive sports in the process, must pay attention to the development and utilization of new materials, development.
文摘HVFA (high-volume fly ash) concrete could be a sustainable way for by-product utilization to conserve natural resources and protect environment. HVFA concrete can play the role of a high-performance material that may be comparable to the conventional Portland cement concrete. The results of the research programme concerning the relationships between the composition of concrete (w/b ratio, fly ash content and type of cement) and their physical and mechanical properties are presented and discussed in the paper. It is found that the introduction of high-volume fly ash into concrete has caused a decrease in compressive strength at the early age of storage. The significant increase in strength was observed between 28 days and 90 days of curing. The high-volume fly ash concretes were characterized with lower water absorbability and sorptivity than control concrete.
基金ACKNOWLEDGEMENT First, thanks for the invitation from the organ- isers of IEEE/CIC ICCC 2013 held in Xi'an, China. This work was supported by the Na- tional Natural Science Foundation of China under Grants No. 60972047, No. 61231008 the National Science and Technology Major Project under Grams No. 2011ZX03005-004, No. 2011ZX03004-003, No. 2011ZX03005- 003-03, No. 2013ZX03004007-003+4 种基金 the Shannxi 13115 Project under Grant No. 2010ZDKG-26 the National Basic Research Program of China (973 Program) under Grant No. 2009CB320404 the Program for Changjiang Scholars and Inn- ovative Research Team in University under Gr- ant No. IRT0852 the 111 Project under Grant No. B08038 and the State Key Laboratory Fou- ndation under Grants No. ISN1002005, No. ISN090305.
文摘Small cells have been regarded as an appealing technique to boost resource reuse ratio. On the other hand, their large-scale and self-organised tendency would complicate the interference environment of mobile networks. Meanwhile, traffic class is booming in recent years, which leads to higher demand for net- work designers on Quality of Service (QoS) provision, and therefore users' diverse re- quirements may not be guaranteed in sucff'an interference limited scenario. To maximise the number of users with QoS demands as well as resource reuse ratio, we formulate the resource allocation problem into a multi-objective l0 norm form. It is shown to be NP hard, and an iterative method is employed to approach the optimal solution. Because of its limit of being not adaptive to large-scale networks, we also design a heuristic method based on chordal graph, which, however, could result in per- formance loss when the size of networks is small. Finally, by combining these two meth- ods, we devise a hybrid algorithm such that the allocation performs both efficiently and effectively. Simulation results illustrate the performance of our proposed methods in terms of outage probability and resource reuse ratio.