Currently,energy saving design has been conducted on single building but not on the whole residential community in urban and rural areas.So,the paper has proposed energy saving measures for residential planning from t...Currently,energy saving design has been conducted on single building but not on the whole residential community in urban and rural areas.So,the paper has proposed energy saving measures for residential planning from the perspective of site selection and layout of buildings.Specific measures are as follows.Firstly,buildings should be constructed on the sunny side and leeside;secondly,buildings on the south should be lower than those on the north;the east side of the building should be open while the west side should be closed;thirdly,climate protection unit should be set;fourthly,buildings should be of northsouth direction primarily,and the main room should be set on the east side and the assistant rooms or passage on the west side in the buildings of east-west direction;fifthly,it should select compact and wellarranged households and the units should not be combined in point and dislocation and jointing.展开更多
In order to have an in-depth understanding of the metal ceiling radiant panel with capillary tubes, a radiant ceiling heating system is constructed to study the actual heating performance and thermal comfort by experi...In order to have an in-depth understanding of the metal ceiling radiant panel with capillary tubes, a radiant ceiling heating system is constructed to study the actual heating performance and thermal comfort by experiments. In addition, the energy saving potential of the novel heating system is discussed in terms of the COP (coefficient of performance) of the ground source heat pump and the exergy efficiency of the radiant terminal. The results indicate that the heating system shows high thermal stability and thermal comfort. When the system reaches a stable condition, the radiant heat transfer accounts for 62.7% of the total heat transfer, and the total heat transfer can meet the heating demands of most buildings. Compared to a radiant floor heating system, it offers advantages in a shorter preheating time, a lower supply water temperature and a stronger heating capability. The COP of the ground source heat pump is increased greatly when the supply water temperature is 28 to 33 ℃, and the exergy efficiency of the metal ceiling with capillary tubes is 1.6 times that of the radiant floor when the reference temperature is 5 ℃ The novel radiant ceiling heating system shows a tremendous energy saving potential.展开更多
A hybrid ground-coupled heat pump(HGCHP)project in Nanjing,China is chosen to analyze the building energy-consumption properties in terms of different control strategies,building envelope and the terminal air-condit...A hybrid ground-coupled heat pump(HGCHP)project in Nanjing,China is chosen to analyze the building energy-consumption properties in terms of different control strategies,building envelope and the terminal air-conditioning system.The HGCHP uses a supplemental heat rejecter to dissipate extra thermal energy to guarantee underground soil heat balance.The software EnergyPlus is employed to simulate the project and design the heat flow of the cooling tower and the borehole heat exchanger(BHE).Then two feasible control strategies for the cooling tower and the borehole heat exchanger are proposed.The energy-saving potential of the building envelope is analyzed in terms of the surface color of the wall/roof.With the same terminal system,it is found that in the cooling season the heat flow of the insulated building with black wall/roof is 1.2 times more than that with white wall/roof.With the same insulated building and gray wall/roof,it is concluded that the heat pump units for a primary air fan-coil system show an annual energy consumption increase of 44.7 GJ compared with a radiant floor system.展开更多
Academics have yet to agree on the effectiveness of the precautionary saving theory in explaining Chinese households’saving behavior.With the Wenchuan megaearthquake of 2008 as an uncertain event to overcome the endo...Academics have yet to agree on the effectiveness of the precautionary saving theory in explaining Chinese households’saving behavior.With the Wenchuan megaearthquake of 2008 as an uncertain event to overcome the endogeneity problem of income volatility,this paper puts forward a brand-new hypothesis that"an earthquake influences household saving rate through its effects on expected income and the variance of expected income."Then,we employ propensity score matching-difference-in-differences(PSMDID)method,the systematic GMM methods,the synthetic control method,together with instrumental variable method,for an analysis of Chinese Household Income Project(CHIP)and inter-provincial data at the micro and macro levels,respectively.We find that the Wenchuan mega-earthquake was followed by an increase in the variance of household expected income in Sichuan and a significant rise in the household saving rate.Second,social protection is negatively correlated with expected income,and has a significant substitutive relationship with saving rate.This finding indirectly proves that the earthquake’s impact on the household saving rate is subject to the variance of expected income,shedding light on how the precautionary saving motivation works in the real world.展开更多
The reduction of power consumption is important for wireless communications and networks.To develop the energy-saving technologies for future wireless transmissions and networks,this paper presents two basic study poi...The reduction of power consumption is important for wireless communications and networks.To develop the energy-saving technologies for future wireless transmissions and networks,this paper presents two basic study points:1)The multiple events are merged into a single event;2)the high-order mode is changed to the low-order mode.For this rea⁃son,we seek that multiple events in wireless transmission links are fused into a single event from Shannon formulas.We also analyze the relationship between the information modula⁃tion and the error correction,and give a fusion structure of error-corrected modulation.The energy-saving performance of the error-corrected modulation method is further analyzed through comparison with the traditional methods of modulation plus error correction.The re⁃sults of numerical analysis demonstrate the wireless energy saving methods for wireless sys⁃tems based on Shannon formulas are the achievable efficient schemes.展开更多
The development of water-saving agriculture is of great significance not only for increasing farmers’ production and income, but also for protecting water resources. The purpose of this paper is to learn from the exp...The development of water-saving agriculture is of great significance not only for increasing farmers’ production and income, but also for protecting water resources. The purpose of this paper is to learn from the experience of Israel, Japan, Korea and Singapore, improve the low efficiency of agricultural water use in China, and solve the problem of water shortage, promote the development of agriculture. This article concludes that the experience of water-saving agriculture in Israel is advanced irrigation technology, sound laws and regulations, and emphasis on science and technology. Japan’s water-saving agriculture is characterized by an efficient irrigation program and a strict agricultural water management policy. Korea’s experience in water-saving agriculture is that it has a strict water management system, with the government subsidizing the cost of irrigation projects and integrating water into agricultural development planning. Singapore’s experience in water-saving agriculture is to raise awareness of water conservation and to use step water prices. In order to promote the sustainable development of water-saving agriculture in China, the research on water-saving agriculture in the future can be carried out from the aspects of agricultural production or related agricultural technology.展开更多
Denim is widely accepted among exported textile products due to its aesthetics, appearance, and fashion. Practitioners employed several physical or chemical treatments to improve denim qualities in denim finishing ope...Denim is widely accepted among exported textile products due to its aesthetics, appearance, and fashion. Practitioners employed several physical or chemical treatments to improve denim qualities in denim finishing operations. So, several treatment processes, including enzymatic, bleaching, singeing, heat set, and ozone finish, are used, which made this processing more energy consumption and time-consuming. Therefore, it is significant to investigate how changing the chemicals and raw ingredients could improve the finishing process, which is environmentally and economically beneficial for sustainable production practices in the denim finishing process. This study’s research design comprises an experimental investigation in a denim plant in Bangladesh. Two different fabrics were chosen to analyze, determining the potential savings of finishing on the denim fabrics’ performance characteristics. By deducting singeing and heat-set processes, the researchers ran an experimental process by maintaining the same length of fabric. Then, the impacts of finishing process optimization on the mechanical, thermal, and comfort parameters of drape, stiffness, and tear strength were examined. The study’s findings demonstrated that this experiment increased productivity and reduced the finishing unit’s energy consumption without compromising the denim fabrics’ quality. This study significantly impacts environmental sustainability by preserving limited energy resources and manufacturing denim finishing processes.展开更多
In the 13th century,the famous Italian traveller,Marco Polo,travelled a long way to China.During his stay in China,he saw many wonderful things. One of the things he discovered(发现)
In the 13th century,the famous Italian traveller,Marco Polo,travelled a long way to China.During his stay in China,he saw many wonderful things. One of the things he discovered(发现)
To improve ground vehicle efficiency, shift schedule energy saving was proposed for the ground vehicle automatic transmission by studying the function of the torque converter and transmission in the vehicular drivetra...To improve ground vehicle efficiency, shift schedule energy saving was proposed for the ground vehicle automatic transmission by studying the function of the torque converter and transmission in the vehicular drivetrain. The shift schedule can keep the torque converter working in the high efficiency range under all the working conditions except in the low efficiency range on the left when the transmission worked at the lowest shift, and in the low efficiency range on the right when the transmission worked at the highest shift. The shift quality key factors were analysed. The automatic trans-mission's bench-test adopting this shift schedule was made on the automatic transmission's test-bed. The experimental results showed that the shift schedule was correct and that the shift quality was controllable.展开更多
The artificial ground freezing(AGF)systems are designed to operate continuously for an extended period of time to control the groundwater seepage and to strengthen the groundwater structure surrounding excavation area...The artificial ground freezing(AGF)systems are designed to operate continuously for an extended period of time to control the groundwater seepage and to strengthen the groundwater structure surrounding excavation areas.This mode of operation requires a massive amount of energy to sustain the thickness of the frozen body.Therefore,it is of great interest to propose new concepts to reduce energy consumption while providing sufficient structural stability and safe operation.This paper discusses the principle of the freezing on demand(FoD)by means of experiment and mathematical model.A lab-scale rig that mimics the AGF process is conceived and developed.The setup is equipped with more than 80 thermocouples,flow-meters,and advanced instrumentation system to analyze the performance of the AGF process under the FoD concept.A mathematical model has been derived,validated,and utilized to simulate the transient FoD concept.The results suggest that the overall energy saving notably depends on the coolant’s temperature;the energy saving increases while decreasing the coolant inlet temperature.Moreover,applying the FoD concept in an AGF system leads to a significant drop in energy consumption.展开更多
In order to save energy and make more efficient use of wireless channel, this article puts forward an energy saving cooperative relaying scheme which actuates the cooperative transmis- sion only when the feedback from...In order to save energy and make more efficient use of wireless channel, this article puts forward an energy saving cooperative relaying scheme which actuates the cooperative transmis- sion only when the feedback from the destination indicates failure of the direct transmission. The proposed scheme selects the optimal relay and its corresponding transmission power in each time slot based on channel condition and residual ener- gy with the objective of minimizing energy con- sumption and extending network lifetime. In the study, the f'mite-state Markov channel model is used to characterize the correlation structure of channel fading in wireless networks, and the pro- cedure of relay selection and transmission power decision is formulated as a M arkov decision process. Numerical and simulation results show that the proposed scheme consumes less energy and prolongs the network lifetime.展开更多
Mature technologies exist to reduce the heating,ventilation,and air-conditioning(HVAC) energy associated with ventilation and use ventilation proactively to save energy.This study investigated the energy use impacts i...Mature technologies exist to reduce the heating,ventilation,and air-conditioning(HVAC) energy associated with ventilation and use ventilation proactively to save energy.This study investigated the energy use impacts in U.S.office buildings of multiple alternative ventilation strategies that combined:economizing,demand controlled ventilation(DCV),supply air temperature reset(SR),and/or a doubled ventilation rate.We used energy simulations in a Monte Carlo analysis,sampling 17 building inputs and varying locations to match the climate zone distribution of the U.S.office stock.Results indicated the possibility for significant savings compared to a baseline that ventilated constantly at a minimum rate in both a small office type with a constant air volume(CAV) HVAC system and a medium office type with a variable air volume(VAV) system.In 95%of instances,HVAC source energy savings were 5-25%in the small-CAV office(median:11%) and 6-42%in the medium-VAV office(median:27%).In the small-CAV office,DCV typically saved the most energy,usually from heating,and heating degree days and occupant density were decisive influences.In the medium-VAV office,economizing and SR were most important,DCV usually only had minor impacts,and zone temperature setpoints,along with climate indicators,were the critical influences.Other than infiltration,envelope characteristics did not strongly influence energy impacts.The untapped primary energy savings of alternative ventilation strategies over the 74%of U.S.office floorspace reasonably represented by our modeling was estimated at 36 TWh per year,with an annual value of U.S.$ 1.25 billion.展开更多
The progress of economic globalization,the rapid growth of international trade,and the maritime transportation has played an increasingly significant role in the international supply chain.As a result,worldwide seapor...The progress of economic globalization,the rapid growth of international trade,and the maritime transportation has played an increasingly significant role in the international supply chain.As a result,worldwide seaports have suffered from a central problem,which appears in the form of massive amounts of fuel consumed and exhaust gas fumes emitted from the ships while berthed.Many ports have taken the necessary precautions to overcome this problem,while others still suffer due to the presence of technical and financial constraints.In this paper,the barriers,interconnection standards,rules,regulations,power sources,and economic and environmental analysis related to ships,shore-side power were studied in efforts to find a solution to overcome his problem.As a case study,this paper investigates the practicability,costs and benefits of switching from onboard ship auxiliary engines to shore-side power connection for high-speed crafts called Alkahera while berthed at the port of Safaga,Egypt.The results provide the national electricity grid concept as the best economical selection with 49.03 percent of annual cost saving.Moreover,environmentally,it could achieve an annual reduction in exhaust gas emissions of CO2,CO,NOx,P.M,and SO2by 276,2.32,18.87,0.825 and 3.84 tons,respectively.展开更多
Mobile Ad hoc NETwork (MANET) consists of a set of mobile hosts which can operate independently without infrastructure base stations. Energy saving is a critical issue for MANET since most mobile hosts will operate on...Mobile Ad hoc NETwork (MANET) consists of a set of mobile hosts which can operate independently without infrastructure base stations. Energy saving is a critical issue for MANET since most mobile hosts will operate on battery powers. A cross layer coordinated framework for energy saving is proposed in this letter. On-demand power management, physical layer and medium access control layer dialogue based multi-packet reception, mobile agent based topology discovery and topology control based transmit power-aware and battery power-aware dynamic source routing are some of new ideas in this framework.展开更多
China has achieved economic growth while great carbon emissions reduction in recent years. Amid China's effort to reduce emissions, the Five-Year Plans have guided and motivated local and foreign forces from the gove...China has achieved economic growth while great carbon emissions reduction in recent years. Amid China's effort to reduce emissions, the Five-Year Plans have guided and motivated local and foreign forces from the government, industries, and society to work together. This paper showed that a mediumehigh economic growth gate, industry structure adjustment, and energy structure adjustment, which are guaranteed under the Five-Year Plan, all contribute to energy saving in China. The economy entered a stable growing phase during the 12 th Five-Year Plan, while the economic growth rate declined to 7.8% from 11.2% in the 11 th Five-Year Plan. Simultaneously, the CO2 emissions growth rate declined from8.32%(2009-2012 mean) to 1.82%(2012-2014 mean). Industrial structure adjustment canceled out nearly one-third of the CO2 emissions caused by economic growth. Under the 13 th Five-Year Plan, China will continue its energy saving efforts on the green development path, with greener quotas, a stricter implementation process, and more key projects.展开更多
Evaporation loss from the saturated soil beneath drip irrigation emitters highly influences the irrigation efficiency of drip krigation (D1]. Subsurface drip irrigation (SDI) is one good approach to curb this ineff...Evaporation loss from the saturated soil beneath drip irrigation emitters highly influences the irrigation efficiency of drip krigation (D1]. Subsurface drip irrigation (SDI) is one good approach to curb this inefficiency, but in a new irrigation method, straight tube irrigation (STI), the irrigation tubes do not need to be buried and thus STI is recommended to increase the irrigation efficiency under normal surface-applied DI. STI consists of only connectors and water-transference tubes that can directly transfer irrigation water from the lateral emitters in the drip line to the root zone of plants. Five-month field experiments were carried out in aeolian sand soil in the forest-belts of the Taklimakan Desert, which have poor water storage capacity, to compare the potential water saving between STI and DI. The preliminary results showed that, compared with DI, STI (1) improved the soil water content in soil depths from 40 to 100 cm under the soil surface; (2) achieved the same irrigation effects in relatively shorter irrigation durations; (3) had very little water loss due to deep seepage; and (4) formed a layer of dry sand about 10 to 30 cm thick immediately below the soil surface, which lessened evaporation loss of soil water beneath the emitters on the soil surface. This demonstrates that STI can maximize the water-saving potential of DI through the reduction of wetted soil perimeters on the soil surface. This is valuable information for water-saving engineering applications and projects with STI in arid and semiarid regions.展开更多
Energy consumption of block-cutting machines represents a major cost item in the processing of travertines and other natural stones. Therefore, determining the optimum sawing conditions for a particular stone is of ma...Energy consumption of block-cutting machines represents a major cost item in the processing of travertines and other natural stones. Therefore, determining the optimum sawing conditions for a particular stone is of major importance in the natural stone-processing industry. An experimental study was carried out utilizing a fully instrumented block-cutter to investigate the sawing performances of five different types of travertine blocks during cutting with a circular diamond saw. The sawing tests were performed in the down-cutting mode. Performance measurements were determined by measuring the cutting speed and energy consumption. Then, specific energy was determined. The one main cutting parameter, cutting speed, was varied in the investigation of optimum cutting performance. Furthermore, some physico-mechanical properties of file travertine blocks were determined in the laboratory. As a result, it is found that the energy consumption (specific energy) of block cutting machines is highly affected by cutting speed. It is determined that specific energy value usually decreases when cutting speed increases. When the cutting speed is higher than the determined value, the diamond saw can become stuck in the travertine block; this situation can be a problem for the block-cutting machine. As a result, the optimum cutting speed obtained for the travertine mines examined is approximately 1.5-2.0 m/min.展开更多
Owing to overcoming the characteristics that there are many economic and technical indexes which are fuzzy and incompatibility to each other in evaluating investment project,a new method is proposed.The method is base...Owing to overcoming the characteristics that there are many economic and technical indexes which are fuzzy and incompatibility to each other in evaluating investment project,a new method is proposed.The method is based on the matter-element analysis and combined with the concepts of fuzzy mathematics,which is called the method of fuzzy matter-element analysis.It constructs the compound fuzzy matter element with the investment projects,evaluation factors and their fuzzy value.Through establishing the best subjection degree (fuzzy value),complex fuzzy matter element of relational coefficient and weight aggregation of fuzzy matter-element model,the writer achieves on optimum order of the investment projects according to the calculated relational degree and finds the best project.In this paper,the calculation of weight adopts the analytical hierarchy process method(AHP).Through the actual example,it shows that the model is simple and its calculation is reliable.It is very significant for the engineering evaluated bid and investment decision.展开更多
In the initial period of industrialization a great deal of land is needed for Chinese industry development as well as land resource per person of China is much lower than the average value in the world, thus it is nec...In the initial period of industrialization a great deal of land is needed for Chinese industry development as well as land resource per person of China is much lower than the average value in the world, thus it is necessary to save land in Chinese urban constrUction. This paper mainly discussed the features of urban land use in economic developed coastal cities: one is that the index of urban land per person in middle-small cities was higher than in large cities; another is that urban land has not been used highly and strongly; the third is that the industrial land occupied an irrationally large percentage of whole urban land; the final is that rural enterprises took up a quantity of land. Thereafter, this paper put forward five land-saving measures: first, to adopt the idea of saving land; next, to adjust the land-use structure when redeveloping the old city and alternate some land use when adjusting the industry structure of the city; the third, to develop the system of payment for using land and the management of urban planning; finally to enhance the effective regional plan and the urban landuse plan.展开更多
文摘Currently,energy saving design has been conducted on single building but not on the whole residential community in urban and rural areas.So,the paper has proposed energy saving measures for residential planning from the perspective of site selection and layout of buildings.Specific measures are as follows.Firstly,buildings should be constructed on the sunny side and leeside;secondly,buildings on the south should be lower than those on the north;the east side of the building should be open while the west side should be closed;thirdly,climate protection unit should be set;fourthly,buildings should be of northsouth direction primarily,and the main room should be set on the east side and the assistant rooms or passage on the west side in the buildings of east-west direction;fifthly,it should select compact and wellarranged households and the units should not be combined in point and dislocation and jointing.
基金The National Natural Science Foundation of China(No.51106023)the National Key Technology R&D Program during the12th Five-Year Plan Period(No.2011BAJ03B14)
文摘In order to have an in-depth understanding of the metal ceiling radiant panel with capillary tubes, a radiant ceiling heating system is constructed to study the actual heating performance and thermal comfort by experiments. In addition, the energy saving potential of the novel heating system is discussed in terms of the COP (coefficient of performance) of the ground source heat pump and the exergy efficiency of the radiant terminal. The results indicate that the heating system shows high thermal stability and thermal comfort. When the system reaches a stable condition, the radiant heat transfer accounts for 62.7% of the total heat transfer, and the total heat transfer can meet the heating demands of most buildings. Compared to a radiant floor heating system, it offers advantages in a shorter preheating time, a lower supply water temperature and a stronger heating capability. The COP of the ground source heat pump is increased greatly when the supply water temperature is 28 to 33 ℃, and the exergy efficiency of the metal ceiling with capillary tubes is 1.6 times that of the radiant floor when the reference temperature is 5 ℃ The novel radiant ceiling heating system shows a tremendous energy saving potential.
文摘A hybrid ground-coupled heat pump(HGCHP)project in Nanjing,China is chosen to analyze the building energy-consumption properties in terms of different control strategies,building envelope and the terminal air-conditioning system.The HGCHP uses a supplemental heat rejecter to dissipate extra thermal energy to guarantee underground soil heat balance.The software EnergyPlus is employed to simulate the project and design the heat flow of the cooling tower and the borehole heat exchanger(BHE).Then two feasible control strategies for the cooling tower and the borehole heat exchanger are proposed.The energy-saving potential of the building envelope is analyzed in terms of the surface color of the wall/roof.With the same terminal system,it is found that in the cooling season the heat flow of the insulated building with black wall/roof is 1.2 times more than that with white wall/roof.With the same insulated building and gray wall/roof,it is concluded that the heat pump units for a primary air fan-coil system show an annual energy consumption increase of 44.7 GJ compared with a radiant floor system.
文摘Academics have yet to agree on the effectiveness of the precautionary saving theory in explaining Chinese households’saving behavior.With the Wenchuan megaearthquake of 2008 as an uncertain event to overcome the endogeneity problem of income volatility,this paper puts forward a brand-new hypothesis that"an earthquake influences household saving rate through its effects on expected income and the variance of expected income."Then,we employ propensity score matching-difference-in-differences(PSMDID)method,the systematic GMM methods,the synthetic control method,together with instrumental variable method,for an analysis of Chinese Household Income Project(CHIP)and inter-provincial data at the micro and macro levels,respectively.We find that the Wenchuan mega-earthquake was followed by an increase in the variance of household expected income in Sichuan and a significant rise in the household saving rate.Second,social protection is negatively correlated with expected income,and has a significant substitutive relationship with saving rate.This finding indirectly proves that the earthquake’s impact on the household saving rate is subject to the variance of expected income,shedding light on how the precautionary saving motivation works in the real world.
基金This work was supported by National Natural Science Foundation of Chi⁃na(NSFC)under Grant No.61631018.
文摘The reduction of power consumption is important for wireless communications and networks.To develop the energy-saving technologies for future wireless transmissions and networks,this paper presents two basic study points:1)The multiple events are merged into a single event;2)the high-order mode is changed to the low-order mode.For this rea⁃son,we seek that multiple events in wireless transmission links are fused into a single event from Shannon formulas.We also analyze the relationship between the information modula⁃tion and the error correction,and give a fusion structure of error-corrected modulation.The energy-saving performance of the error-corrected modulation method is further analyzed through comparison with the traditional methods of modulation plus error correction.The re⁃sults of numerical analysis demonstrate the wireless energy saving methods for wireless sys⁃tems based on Shannon formulas are the achievable efficient schemes.
文摘The development of water-saving agriculture is of great significance not only for increasing farmers’ production and income, but also for protecting water resources. The purpose of this paper is to learn from the experience of Israel, Japan, Korea and Singapore, improve the low efficiency of agricultural water use in China, and solve the problem of water shortage, promote the development of agriculture. This article concludes that the experience of water-saving agriculture in Israel is advanced irrigation technology, sound laws and regulations, and emphasis on science and technology. Japan’s water-saving agriculture is characterized by an efficient irrigation program and a strict agricultural water management policy. Korea’s experience in water-saving agriculture is that it has a strict water management system, with the government subsidizing the cost of irrigation projects and integrating water into agricultural development planning. Singapore’s experience in water-saving agriculture is to raise awareness of water conservation and to use step water prices. In order to promote the sustainable development of water-saving agriculture in China, the research on water-saving agriculture in the future can be carried out from the aspects of agricultural production or related agricultural technology.
文摘Denim is widely accepted among exported textile products due to its aesthetics, appearance, and fashion. Practitioners employed several physical or chemical treatments to improve denim qualities in denim finishing operations. So, several treatment processes, including enzymatic, bleaching, singeing, heat set, and ozone finish, are used, which made this processing more energy consumption and time-consuming. Therefore, it is significant to investigate how changing the chemicals and raw ingredients could improve the finishing process, which is environmentally and economically beneficial for sustainable production practices in the denim finishing process. This study’s research design comprises an experimental investigation in a denim plant in Bangladesh. Two different fabrics were chosen to analyze, determining the potential savings of finishing on the denim fabrics’ performance characteristics. By deducting singeing and heat-set processes, the researchers ran an experimental process by maintaining the same length of fabric. Then, the impacts of finishing process optimization on the mechanical, thermal, and comfort parameters of drape, stiffness, and tear strength were examined. The study’s findings demonstrated that this experiment increased productivity and reduced the finishing unit’s energy consumption without compromising the denim fabrics’ quality. This study significantly impacts environmental sustainability by preserving limited energy resources and manufacturing denim finishing processes.
文摘In the 13th century,the famous Italian traveller,Marco Polo,travelled a long way to China.During his stay in China,he saw many wonderful things. One of the things he discovered(发现)
文摘In the 13th century,the famous Italian traveller,Marco Polo,travelled a long way to China.During his stay in China,he saw many wonderful things. One of the things he discovered(发现)
文摘To improve ground vehicle efficiency, shift schedule energy saving was proposed for the ground vehicle automatic transmission by studying the function of the torque converter and transmission in the vehicular drivetrain. The shift schedule can keep the torque converter working in the high efficiency range under all the working conditions except in the low efficiency range on the left when the transmission worked at the lowest shift, and in the low efficiency range on the right when the transmission worked at the highest shift. The shift quality key factors were analysed. The automatic trans-mission's bench-test adopting this shift schedule was made on the automatic transmission's test-bed. The experimental results showed that the shift schedule was correct and that the shift quality was controllable.
基金McGill Engineering Doctoral Award(MEDA)Fonds de recherche du Québec-Nature et technologies(FRQNT)-Bourses de doctorat(B2X)for supporting this research
文摘The artificial ground freezing(AGF)systems are designed to operate continuously for an extended period of time to control the groundwater seepage and to strengthen the groundwater structure surrounding excavation areas.This mode of operation requires a massive amount of energy to sustain the thickness of the frozen body.Therefore,it is of great interest to propose new concepts to reduce energy consumption while providing sufficient structural stability and safe operation.This paper discusses the principle of the freezing on demand(FoD)by means of experiment and mathematical model.A lab-scale rig that mimics the AGF process is conceived and developed.The setup is equipped with more than 80 thermocouples,flow-meters,and advanced instrumentation system to analyze the performance of the AGF process under the FoD concept.A mathematical model has been derived,validated,and utilized to simulate the transient FoD concept.The results suggest that the overall energy saving notably depends on the coolant’s temperature;the energy saving increases while decreasing the coolant inlet temperature.Moreover,applying the FoD concept in an AGF system leads to a significant drop in energy consumption.
基金The authors would like to thank the reviewers for their de-tailed reviews and constructive comments, which have helped improve the quality of this paper. This work was supported by the National Natural Science Foundation of China under Grant No. 61101107 the Scientific Research and Innovation Plan for the Youth of BUPT under Grant No. 2011RC0305 the National International Science and Technology Cooperation Project under Grant No. 2010DFA11320.
文摘In order to save energy and make more efficient use of wireless channel, this article puts forward an energy saving cooperative relaying scheme which actuates the cooperative transmis- sion only when the feedback from the destination indicates failure of the direct transmission. The proposed scheme selects the optimal relay and its corresponding transmission power in each time slot based on channel condition and residual ener- gy with the objective of minimizing energy con- sumption and extending network lifetime. In the study, the f'mite-state Markov channel model is used to characterize the correlation structure of channel fading in wireless networks, and the pro- cedure of relay selection and transmission power decision is formulated as a M arkov decision process. Numerical and simulation results show that the proposed scheme consumes less energy and prolongs the network lifetime.
文摘Mature technologies exist to reduce the heating,ventilation,and air-conditioning(HVAC) energy associated with ventilation and use ventilation proactively to save energy.This study investigated the energy use impacts in U.S.office buildings of multiple alternative ventilation strategies that combined:economizing,demand controlled ventilation(DCV),supply air temperature reset(SR),and/or a doubled ventilation rate.We used energy simulations in a Monte Carlo analysis,sampling 17 building inputs and varying locations to match the climate zone distribution of the U.S.office stock.Results indicated the possibility for significant savings compared to a baseline that ventilated constantly at a minimum rate in both a small office type with a constant air volume(CAV) HVAC system and a medium office type with a variable air volume(VAV) system.In 95%of instances,HVAC source energy savings were 5-25%in the small-CAV office(median:11%) and 6-42%in the medium-VAV office(median:27%).In the small-CAV office,DCV typically saved the most energy,usually from heating,and heating degree days and occupant density were decisive influences.In the medium-VAV office,economizing and SR were most important,DCV usually only had minor impacts,and zone temperature setpoints,along with climate indicators,were the critical influences.Other than infiltration,envelope characteristics did not strongly influence energy impacts.The untapped primary energy savings of alternative ventilation strategies over the 74%of U.S.office floorspace reasonably represented by our modeling was estimated at 36 TWh per year,with an annual value of U.S.$ 1.25 billion.
文摘The progress of economic globalization,the rapid growth of international trade,and the maritime transportation has played an increasingly significant role in the international supply chain.As a result,worldwide seaports have suffered from a central problem,which appears in the form of massive amounts of fuel consumed and exhaust gas fumes emitted from the ships while berthed.Many ports have taken the necessary precautions to overcome this problem,while others still suffer due to the presence of technical and financial constraints.In this paper,the barriers,interconnection standards,rules,regulations,power sources,and economic and environmental analysis related to ships,shore-side power were studied in efforts to find a solution to overcome his problem.As a case study,this paper investigates the practicability,costs and benefits of switching from onboard ship auxiliary engines to shore-side power connection for high-speed crafts called Alkahera while berthed at the port of Safaga,Egypt.The results provide the national electricity grid concept as the best economical selection with 49.03 percent of annual cost saving.Moreover,environmentally,it could achieve an annual reduction in exhaust gas emissions of CO2,CO,NOx,P.M,and SO2by 276,2.32,18.87,0.825 and 3.84 tons,respectively.
基金863" Project Fund (No.2002AA121068) National Natural Science Foundation of China(No.60272066)
文摘Mobile Ad hoc NETwork (MANET) consists of a set of mobile hosts which can operate independently without infrastructure base stations. Energy saving is a critical issue for MANET since most mobile hosts will operate on battery powers. A cross layer coordinated framework for energy saving is proposed in this letter. On-demand power management, physical layer and medium access control layer dialogue based multi-packet reception, mobile agent based topology discovery and topology control based transmit power-aware and battery power-aware dynamic source routing are some of new ideas in this framework.
基金supported by the "study of Green space management system and protection" of mechanism Economic Development Research Center of State Forestry Administration (ZDWT-2014-3)
文摘China has achieved economic growth while great carbon emissions reduction in recent years. Amid China's effort to reduce emissions, the Five-Year Plans have guided and motivated local and foreign forces from the government, industries, and society to work together. This paper showed that a mediumehigh economic growth gate, industry structure adjustment, and energy structure adjustment, which are guaranteed under the Five-Year Plan, all contribute to energy saving in China. The economy entered a stable growing phase during the 12 th Five-Year Plan, while the economic growth rate declined to 7.8% from 11.2% in the 11 th Five-Year Plan. Simultaneously, the CO2 emissions growth rate declined from8.32%(2009-2012 mean) to 1.82%(2012-2014 mean). Industrial structure adjustment canceled out nearly one-third of the CO2 emissions caused by economic growth. Under the 13 th Five-Year Plan, China will continue its energy saving efforts on the green development path, with greener quotas, a stricter implementation process, and more key projects.
基金Tarim Oilfield Corporation of China National Petroleum Corporation for providing funds
文摘Evaporation loss from the saturated soil beneath drip irrigation emitters highly influences the irrigation efficiency of drip krigation (D1]. Subsurface drip irrigation (SDI) is one good approach to curb this inefficiency, but in a new irrigation method, straight tube irrigation (STI), the irrigation tubes do not need to be buried and thus STI is recommended to increase the irrigation efficiency under normal surface-applied DI. STI consists of only connectors and water-transference tubes that can directly transfer irrigation water from the lateral emitters in the drip line to the root zone of plants. Five-month field experiments were carried out in aeolian sand soil in the forest-belts of the Taklimakan Desert, which have poor water storage capacity, to compare the potential water saving between STI and DI. The preliminary results showed that, compared with DI, STI (1) improved the soil water content in soil depths from 40 to 100 cm under the soil surface; (2) achieved the same irrigation effects in relatively shorter irrigation durations; (3) had very little water loss due to deep seepage; and (4) formed a layer of dry sand about 10 to 30 cm thick immediately below the soil surface, which lessened evaporation loss of soil water beneath the emitters on the soil surface. This demonstrates that STI can maximize the water-saving potential of DI through the reduction of wetted soil perimeters on the soil surface. This is valuable information for water-saving engineering applications and projects with STI in arid and semiarid regions.
文摘Energy consumption of block-cutting machines represents a major cost item in the processing of travertines and other natural stones. Therefore, determining the optimum sawing conditions for a particular stone is of major importance in the natural stone-processing industry. An experimental study was carried out utilizing a fully instrumented block-cutter to investigate the sawing performances of five different types of travertine blocks during cutting with a circular diamond saw. The sawing tests were performed in the down-cutting mode. Performance measurements were determined by measuring the cutting speed and energy consumption. Then, specific energy was determined. The one main cutting parameter, cutting speed, was varied in the investigation of optimum cutting performance. Furthermore, some physico-mechanical properties of file travertine blocks were determined in the laboratory. As a result, it is found that the energy consumption (specific energy) of block cutting machines is highly affected by cutting speed. It is determined that specific energy value usually decreases when cutting speed increases. When the cutting speed is higher than the determined value, the diamond saw can become stuck in the travertine block; this situation can be a problem for the block-cutting machine. As a result, the optimum cutting speed obtained for the travertine mines examined is approximately 1.5-2.0 m/min.
基金Project supported by the National High-Tech Research and Development program of China (863 Program ) (No.2 0 0 2 AA2 Z42 5 1-2 10 0 41) Postdoctoral Scientific Foundation of Northeast Agricultural U niversity. (No. 2 40 0 0 9) and postdoctoral Scien
文摘Owing to overcoming the characteristics that there are many economic and technical indexes which are fuzzy and incompatibility to each other in evaluating investment project,a new method is proposed.The method is based on the matter-element analysis and combined with the concepts of fuzzy mathematics,which is called the method of fuzzy matter-element analysis.It constructs the compound fuzzy matter element with the investment projects,evaluation factors and their fuzzy value.Through establishing the best subjection degree (fuzzy value),complex fuzzy matter element of relational coefficient and weight aggregation of fuzzy matter-element model,the writer achieves on optimum order of the investment projects according to the calculated relational degree and finds the best project.In this paper,the calculation of weight adopts the analytical hierarchy process method(AHP).Through the actual example,it shows that the model is simple and its calculation is reliable.It is very significant for the engineering evaluated bid and investment decision.
文摘In the initial period of industrialization a great deal of land is needed for Chinese industry development as well as land resource per person of China is much lower than the average value in the world, thus it is necessary to save land in Chinese urban constrUction. This paper mainly discussed the features of urban land use in economic developed coastal cities: one is that the index of urban land per person in middle-small cities was higher than in large cities; another is that urban land has not been used highly and strongly; the third is that the industrial land occupied an irrationally large percentage of whole urban land; the final is that rural enterprises took up a quantity of land. Thereafter, this paper put forward five land-saving measures: first, to adopt the idea of saving land; next, to adjust the land-use structure when redeveloping the old city and alternate some land use when adjusting the industry structure of the city; the third, to develop the system of payment for using land and the management of urban planning; finally to enhance the effective regional plan and the urban landuse plan.