Engine noise source identification is essential for making noise reduction strategies.Predominant noise sources of engines are normally identified as some cover components such as oil pan, valve cover and front gear c...Engine noise source identification is essential for making noise reduction strategies.Predominant noise sources of engines are normally identified as some cover components such as oil pan, valve cover and front gear cover etc. The radiated noise sources of a 6-cylinder construction diesel engine are identified with two methods-lead covering technique and surface vibration technique,and the ranking of the major cover on the basis of acoustic power is presented in this paper. Firstly the sound power level of these cover components and their contributions to the total acoustic power are determined with lead covering method under hemi-anechoic condition. Then the vibration characteristics of these components are investigated. The sound power level of various components is predicted via the mean square area average vibration. Both results basically agree well and verify the effectiveness of both techniques in engineering field.展开更多
A novel regenerative braking algorithm based on regenerative torque optimization with emulate engine compression braking (EECB) was proposed to make effective and maximum use of brake energy in order to improve fuel e...A novel regenerative braking algorithm based on regenerative torque optimization with emulate engine compression braking (EECB) was proposed to make effective and maximum use of brake energy in order to improve fuel economy.The actual brake oil pressure of driving wheel which is reduced by the amount of the regenerative braking force is supplied from the electronic hydraulic brake system.Regenerative torque optimization maximizes the actual regenerative power recuperation by energy storage component,and EECB is a useful extended type of regenerative braking.The simulation results show that actual regenerative power recuperation for the novel regenerative braking algorithm is more than using conventional one,and life-span of brake disks is prolonged for the novel algorithm.展开更多
Acoustic signals from diesel engines contain useful information but also include considerable noise components To extract information for condition monitoring purposes, continuous wavelet transform (CWT) is used for t...Acoustic signals from diesel engines contain useful information but also include considerable noise components To extract information for condition monitoring purposes, continuous wavelet transform (CWT) is used for the characterization of engine acoustics. This paper first reviews CWT characteristics represented by short duration transient signals. Wavelet selection and CWT are then implemented and wavelet transform is used to analyze the major sources of the engine front's exterior radiation sound. The research provides a reliable basis for engineering practice to reduce vehicle sound level. Comparison of the identification results of the measured acoustic signals with the identification results of the measured surface vibration showed good agreement.展开更多
A new approach for dynamic Web services discovery based on similarity computation in the treatment of massive Web information resource is put forward. Firstly, three kinds of service description information, textual, ...A new approach for dynamic Web services discovery based on similarity computation in the treatment of massive Web information resource is put forward. Firstly, three kinds of service description information, textual, semantic and structural information, were modeled to compute the similarity of services. Then a novel dynamic Web services discovery mechanism was provided and the experiment on it was carried out. Results show that the new approach achieves considerable performance on precision and efficiency metrics for dynamic Web services discovery.展开更多
For an energy-efficient induction machine, the life-cycle cost (LCC) usually is the most important index to the consumer. With this target, the optimization design of a motor is a complex nonlinear problem with constr...For an energy-efficient induction machine, the life-cycle cost (LCC) usually is the most important index to the consumer. With this target, the optimization design of a motor is a complex nonlinear problem with constraints. To solve the problem, the authors introduce a united random algorithm. At first, the problem is divided into two parts, the optimal rotor slots and the optimization of other dimensions. Before optimizing the rotor slots with genetic algorithm ( GA), the second part is solved with TABU algorithm to simplify the problem. The numerical results showed that this method is better than the method using a traditional algorithm.展开更多
Energy and environmental sustainability are important considerations for increased rice production. This study examined the energy utilization and sustainability of rice processing in sub-Saharan Africa. The community...Energy and environmental sustainability are important considerations for increased rice production. This study examined the energy utilization and sustainability of rice processing in sub-Saharan Africa. The community of Gadan Loko village in the song local government of Adamawa State, Nigeria was selected as the focus of study. Rice parboiling, the most energy intensive process in rice processing is carried out usually by women in small quantities of about 13.2 kg using traditional pots on tripod support stoves. The parboiled rice is sun dried on mats before it is taken to the milling stalls where it is milled using milling machines driven by single cylinder diesel engines. There were large variations in the quality of milled rice due to lack of consistency in processing parameters. Accumulation of rice husk in the community created important environmental issues. In this study, methods of improving sustainability of rice processing were investigated. The areas included: the utilization of waste heat from the diesel engines for improved drying and efficient pre-soaking; the utilization of solar energy for pre-soaking; the utilization of rice husks as alternative fuel to firewood; and the optimization and redesign of the stoves and parboiling vessels to minimize heat loss to the environment. The results showed that the utilization of rice husk as alternative fuel and the redesign of the stoves and parboiling vessels will increase the sustainability of rice processing and can be easily adopted by the community. While solar energy pre-soaking was not economical and the utilization of waste heat from the diesel engines for drying and pre-soaking would be difficult to implement at the rural scale, because most of the parboiling is done far away from the milling stalls. The study showed that research, development of appropriate technology, and education (RATE) of the rural community is an important way of increasing sustainability.展开更多
The objective of this work is to show the benefits of a new eco-systemic fishing gear installed in three bottom trawlers after one year using it. The study has been based on fuel consumption reduction for the three ve...The objective of this work is to show the benefits of a new eco-systemic fishing gear installed in three bottom trawlers after one year using it. The study has been based on fuel consumption reduction for the three vessels and the catch in two of them. The new system minimizes the impact of the fishing gear on the seabed, with a reduction on the tow resistance. This generates significant fuel savings that improves the economical result of the fishery, helping the ship owners in the return of investment first, then in the future viability of the operation. Apart of the evident savings due to the fuel consumption reduction, in the long term, the ship owner will notice also savings on maintenance, both because the winches are towing with less tension (longer life for warps, brakes and hydraulic system) and the engine is running at low rpm's (longer life of the engine and between breakdowns). The new fishing gear does not require any modification on the way that the fisherman is working, only replacing and/or modifying some parts or components of the fishing gear. The implementation is easy and the adjustments required could be done in a couple of days.展开更多
In order to expand the natural energy and the energy conservation, "the smart PV (photovoltaic power generation) & EV (electric vehicle) system" has been proposed and the effect has been clarified. In the smart...In order to expand the natural energy and the energy conservation, "the smart PV (photovoltaic power generation) & EV (electric vehicle) system" has been proposed and the effect has been clarified. In the smart PV & EV system, it is important that electric vehicles become popular. Therefore, the AI-EV (air-conditioner integrated electric vehicle) has been proposed. In this paper, the AI-EV is designed based on the required car air-conditioner capacity. And, the value of AI-EV is compared with a gasoline vehicle, HV (hybrid vehicle) and EV using the mathematical simulation model As a result, it is clarified that the minimum displacement of the small-engine is 120 cc for AI-EV. In the smart PV & EV system, AI-EV can reduce CO_2 emissions by 20% almost the same as EV. Additionally, AI-EV is able to gain the cruising range more than twice as long as EV.展开更多
In order to reduce the noise and vibration of the diesel engine,it is crucial to exactly identify the engine noise source character.Based on "two-microphone" method,the sound intensity measurement of a vehic...In order to reduce the noise and vibration of the diesel engine,it is crucial to exactly identify the engine noise source character.Based on "two-microphone" method,the sound intensity measurement of a vehicle four-stroke diesel engine was carried out in a hemi-anechoic chamber.Then the sound intensity contour maps were obtained from the measurement results and the main noise components of different frequencies on all the measurement surfaces were picked out to construct contour maps.By analysizing the relationship between the characteristics of contour maps and the space distribution of the engine compartment,the major sources of the exterior radiation noise of the diesel engine were identified.The results provided a creditable basis for improving the noise performance of the engine in the next phase.展开更多
After the great east Japan earthquake in 2011, Japanese energy system has been expected to prioritize safety and trustworthiness. Now, distributed power systems are considered as one solution, but utilizing exhaust he...After the great east Japan earthquake in 2011, Japanese energy system has been expected to prioritize safety and trustworthiness. Now, distributed power systems are considered as one solution, but utilizing exhaust heat is an important task to be solved. The purpose of this study is to build a simulation model to harness waste heat of commercial buildings. We obtained two types of data: distributed power system in 1/15 scale model of supermarket, restaurant and real world energy consumption of the two buildings. Results showed cold cabinets, whose electricity was affected by temperatures outside and inside, consumed most in supermarket. While air conditioning, affected by air enthalpy of outside and inside, consumed most in restaurant. According to our simulation with gas engine, PV (photovoltaic) panel, PCM (phase change material), thermal storage, FCU (fan coil unit) and refrigerated cabinets in scale model, we could reduce 27% of CO_2 emission and 25% of running cost by selecting optimal size.展开更多
The regional tectonic background and characteristics of active faults of the Yutian MS7.3earthquake on February 12,2014 are discussed in this paper.After the analysis of the epicenter area of the MS7.3 earthquake in 2...The regional tectonic background and characteristics of active faults of the Yutian MS7.3earthquake on February 12,2014 are discussed in this paper.After the analysis of the epicenter area of the MS7.3 earthquake in 2014 and the focal mechanisms of the former strong earthquakes around it,the authors deduced that the seismogenic fault of the MS7.3earthquake is the east branch of the Ashikule fault.The MS7.3 earthquake in 2014 and the MS7.3 earthquake in 2008 are two strong earthquake events on the different sections of the Altun Tagh fault,where the fault behavior changes from sinistral slip to normal faulting because of the extensional tail effects in the southern end of the Altun Tagh fault.It is concluded that the two MS7.3 earthquakes have the same dynamic source,and the MS7.3earthquake in 2008 promoted the occurrence of the MS7.3 earthquake in 2014.Finally,we calculate the Coulomb stress change to the seismogenic fault of the MS7.3 earthquake in2014 from the MS7.3 earthquake in 2008 using the layered crust model.The result also shows that the MS7.3 earthquake in 2008 accelerated the occurrence of the MS7.3earthquake in 2014.展开更多
The paper is devoted to new, experimentally registered thermo physical problems of high temperature applied external and internal aerodynamics which is defined first of all by intensive interaction of the gaseous medi...The paper is devoted to new, experimentally registered thermo physical problems of high temperature applied external and internal aerodynamics which is defined first of all by intensive interaction of the gaseous media and thermal radiation. The first report section analyses basic complexities of designing high temperature air breathing engines related to origin of so-called "unexpected" heat of working process. The next parts of the report consider physical, chemical and plasma features of aerodynamics of reentry space blunt bodies and meteors with specified account of thermal radiation influence. Our solutions are based on the classical Dark Matter-Energy simulation. We present special experimental data for Dark Matter pressure registration on the earth conditions.展开更多
The combination of new intelligent materials and structure technology is becoming an effective way in energy havesting and self-powered sensing. In this work, we demonstrate a magnetically levitated/piezoelectric/trib...The combination of new intelligent materials and structure technology is becoming an effective way in energy havesting and self-powered sensing. In this work, we demonstrate a magnetically levitated/piezoelectric/triboelectric hybrid generator, which does not use complex structure and has high steady output performance. It includes three parts: magnetically levitated generator(MLG), piezoelectric generator(PNG), triboelectric nanogenerator(TENG). The peak power of each is 135 μW, 22 mW and3.6 mW, which are obtained at 1 MΩ, 10 kΩ and 1 kΩ, respectively. The hybrid generator can completely light up light-emitting diodes(LEDs) under the vibration frequency of 20 Hz and the vibration amplitude of 10 mm. It also can charge a 470 μF capacitor.On this basis, we have integrated the hybrid generaor as a power supply into a self-powered tempreature sensing system. The combination of three generators can not only broaden the operating range, but also increase the operating length and sensitivity.This work will extend the application of self-powered sensor in automatic production line and promote the development of industrial control technology.展开更多
文摘Engine noise source identification is essential for making noise reduction strategies.Predominant noise sources of engines are normally identified as some cover components such as oil pan, valve cover and front gear cover etc. The radiated noise sources of a 6-cylinder construction diesel engine are identified with two methods-lead covering technique and surface vibration technique,and the ranking of the major cover on the basis of acoustic power is presented in this paper. Firstly the sound power level of these cover components and their contributions to the total acoustic power are determined with lead covering method under hemi-anechoic condition. Then the vibration characteristics of these components are investigated. The sound power level of various components is predicted via the mean square area average vibration. Both results basically agree well and verify the effectiveness of both techniques in engineering field.
基金The National Hi-Tech Research and Development Program(863)of China(No.2002AA501700No.2003AA501012)
文摘A novel regenerative braking algorithm based on regenerative torque optimization with emulate engine compression braking (EECB) was proposed to make effective and maximum use of brake energy in order to improve fuel economy.The actual brake oil pressure of driving wheel which is reduced by the amount of the regenerative braking force is supplied from the electronic hydraulic brake system.Regenerative torque optimization maximizes the actual regenerative power recuperation by energy storage component,and EECB is a useful extended type of regenerative braking.The simulation results show that actual regenerative power recuperation for the novel regenerative braking algorithm is more than using conventional one,and life-span of brake disks is prolonged for the novel algorithm.
基金Project (No. 50175078) supported by the National Natural Science Foundation of China
文摘Acoustic signals from diesel engines contain useful information but also include considerable noise components To extract information for condition monitoring purposes, continuous wavelet transform (CWT) is used for the characterization of engine acoustics. This paper first reviews CWT characteristics represented by short duration transient signals. Wavelet selection and CWT are then implemented and wavelet transform is used to analyze the major sources of the engine front's exterior radiation sound. The research provides a reliable basis for engineering practice to reduce vehicle sound level. Comparison of the identification results of the measured acoustic signals with the identification results of the measured surface vibration showed good agreement.
基金Sponsored by the National Basic Research Development Program of China (973 Program) (Grant No.2005CB321901)
文摘A new approach for dynamic Web services discovery based on similarity computation in the treatment of massive Web information resource is put forward. Firstly, three kinds of service description information, textual, semantic and structural information, were modeled to compute the similarity of services. Then a novel dynamic Web services discovery mechanism was provided and the experiment on it was carried out. Results show that the new approach achieves considerable performance on precision and efficiency metrics for dynamic Web services discovery.
文摘For an energy-efficient induction machine, the life-cycle cost (LCC) usually is the most important index to the consumer. With this target, the optimization design of a motor is a complex nonlinear problem with constraints. To solve the problem, the authors introduce a united random algorithm. At first, the problem is divided into two parts, the optimal rotor slots and the optimization of other dimensions. Before optimizing the rotor slots with genetic algorithm ( GA), the second part is solved with TABU algorithm to simplify the problem. The numerical results showed that this method is better than the method using a traditional algorithm.
文摘Energy and environmental sustainability are important considerations for increased rice production. This study examined the energy utilization and sustainability of rice processing in sub-Saharan Africa. The community of Gadan Loko village in the song local government of Adamawa State, Nigeria was selected as the focus of study. Rice parboiling, the most energy intensive process in rice processing is carried out usually by women in small quantities of about 13.2 kg using traditional pots on tripod support stoves. The parboiled rice is sun dried on mats before it is taken to the milling stalls where it is milled using milling machines driven by single cylinder diesel engines. There were large variations in the quality of milled rice due to lack of consistency in processing parameters. Accumulation of rice husk in the community created important environmental issues. In this study, methods of improving sustainability of rice processing were investigated. The areas included: the utilization of waste heat from the diesel engines for improved drying and efficient pre-soaking; the utilization of solar energy for pre-soaking; the utilization of rice husks as alternative fuel to firewood; and the optimization and redesign of the stoves and parboiling vessels to minimize heat loss to the environment. The results showed that the utilization of rice husk as alternative fuel and the redesign of the stoves and parboiling vessels will increase the sustainability of rice processing and can be easily adopted by the community. While solar energy pre-soaking was not economical and the utilization of waste heat from the diesel engines for drying and pre-soaking would be difficult to implement at the rural scale, because most of the parboiling is done far away from the milling stalls. The study showed that research, development of appropriate technology, and education (RATE) of the rural community is an important way of increasing sustainability.
文摘The objective of this work is to show the benefits of a new eco-systemic fishing gear installed in three bottom trawlers after one year using it. The study has been based on fuel consumption reduction for the three vessels and the catch in two of them. The new system minimizes the impact of the fishing gear on the seabed, with a reduction on the tow resistance. This generates significant fuel savings that improves the economical result of the fishery, helping the ship owners in the return of investment first, then in the future viability of the operation. Apart of the evident savings due to the fuel consumption reduction, in the long term, the ship owner will notice also savings on maintenance, both because the winches are towing with less tension (longer life for warps, brakes and hydraulic system) and the engine is running at low rpm's (longer life of the engine and between breakdowns). The new fishing gear does not require any modification on the way that the fisherman is working, only replacing and/or modifying some parts or components of the fishing gear. The implementation is easy and the adjustments required could be done in a couple of days.
文摘In order to expand the natural energy and the energy conservation, "the smart PV (photovoltaic power generation) & EV (electric vehicle) system" has been proposed and the effect has been clarified. In the smart PV & EV system, it is important that electric vehicles become popular. Therefore, the AI-EV (air-conditioner integrated electric vehicle) has been proposed. In this paper, the AI-EV is designed based on the required car air-conditioner capacity. And, the value of AI-EV is compared with a gasoline vehicle, HV (hybrid vehicle) and EV using the mathematical simulation model As a result, it is clarified that the minimum displacement of the small-engine is 120 cc for AI-EV. In the smart PV & EV system, AI-EV can reduce CO_2 emissions by 20% almost the same as EV. Additionally, AI-EV is able to gain the cruising range more than twice as long as EV.
基金supported by programfor the Top Young Academic Leaders of Higher Learning Institutions of Shanxi(2009)Natural Science Foundation of Shanxi Province,China(No.2010011031-2)
文摘In order to reduce the noise and vibration of the diesel engine,it is crucial to exactly identify the engine noise source character.Based on "two-microphone" method,the sound intensity measurement of a vehicle four-stroke diesel engine was carried out in a hemi-anechoic chamber.Then the sound intensity contour maps were obtained from the measurement results and the main noise components of different frequencies on all the measurement surfaces were picked out to construct contour maps.By analysizing the relationship between the characteristics of contour maps and the space distribution of the engine compartment,the major sources of the exterior radiation noise of the diesel engine were identified.The results provided a creditable basis for improving the noise performance of the engine in the next phase.
文摘After the great east Japan earthquake in 2011, Japanese energy system has been expected to prioritize safety and trustworthiness. Now, distributed power systems are considered as one solution, but utilizing exhaust heat is an important task to be solved. The purpose of this study is to build a simulation model to harness waste heat of commercial buildings. We obtained two types of data: distributed power system in 1/15 scale model of supermarket, restaurant and real world energy consumption of the two buildings. Results showed cold cabinets, whose electricity was affected by temperatures outside and inside, consumed most in supermarket. While air conditioning, affected by air enthalpy of outside and inside, consumed most in restaurant. According to our simulation with gas engine, PV (photovoltaic) panel, PCM (phase change material), thermal storage, FCU (fan coil unit) and refrigerated cabinets in scale model, we could reduce 27% of CO_2 emission and 25% of running cost by selecting optimal size.
基金funded by the Spark Program of Earthquake Science of China(XH15047Y)the National Science Foundation of China(41404043)
文摘The regional tectonic background and characteristics of active faults of the Yutian MS7.3earthquake on February 12,2014 are discussed in this paper.After the analysis of the epicenter area of the MS7.3 earthquake in 2014 and the focal mechanisms of the former strong earthquakes around it,the authors deduced that the seismogenic fault of the MS7.3earthquake is the east branch of the Ashikule fault.The MS7.3 earthquake in 2014 and the MS7.3 earthquake in 2008 are two strong earthquake events on the different sections of the Altun Tagh fault,where the fault behavior changes from sinistral slip to normal faulting because of the extensional tail effects in the southern end of the Altun Tagh fault.It is concluded that the two MS7.3 earthquakes have the same dynamic source,and the MS7.3earthquake in 2008 promoted the occurrence of the MS7.3 earthquake in 2014.Finally,we calculate the Coulomb stress change to the seismogenic fault of the MS7.3 earthquake in2014 from the MS7.3 earthquake in 2008 using the layered crust model.The result also shows that the MS7.3 earthquake in 2008 accelerated the occurrence of the MS7.3earthquake in 2014.
文摘The paper is devoted to new, experimentally registered thermo physical problems of high temperature applied external and internal aerodynamics which is defined first of all by intensive interaction of the gaseous media and thermal radiation. The first report section analyses basic complexities of designing high temperature air breathing engines related to origin of so-called "unexpected" heat of working process. The next parts of the report consider physical, chemical and plasma features of aerodynamics of reentry space blunt bodies and meteors with specified account of thermal radiation influence. Our solutions are based on the classical Dark Matter-Energy simulation. We present special experimental data for Dark Matter pressure registration on the earth conditions.
基金supported by the National Natural Science Foundation of China(Grant Nos.61525107,51422510&51605449)the National High Technology Research and Development Program of China(Grant No.2015AA042601)
文摘The combination of new intelligent materials and structure technology is becoming an effective way in energy havesting and self-powered sensing. In this work, we demonstrate a magnetically levitated/piezoelectric/triboelectric hybrid generator, which does not use complex structure and has high steady output performance. It includes three parts: magnetically levitated generator(MLG), piezoelectric generator(PNG), triboelectric nanogenerator(TENG). The peak power of each is 135 μW, 22 mW and3.6 mW, which are obtained at 1 MΩ, 10 kΩ and 1 kΩ, respectively. The hybrid generator can completely light up light-emitting diodes(LEDs) under the vibration frequency of 20 Hz and the vibration amplitude of 10 mm. It also can charge a 470 μF capacitor.On this basis, we have integrated the hybrid generaor as a power supply into a self-powered tempreature sensing system. The combination of three generators can not only broaden the operating range, but also increase the operating length and sensitivity.This work will extend the application of self-powered sensor in automatic production line and promote the development of industrial control technology.