The utilization of prefabricated light modular radiant heating system has demonstrated significant increases in heat transfer efficiency and energy conservation capabilities.Within prefabricated building construction,...The utilization of prefabricated light modular radiant heating system has demonstrated significant increases in heat transfer efficiency and energy conservation capabilities.Within prefabricated building construction,this new heating method presents an opportunity for the development of comprehensive facilities.The parameters for evaluating the effectiveness of such a system are the upper surface layer’s heat flux and temperature.In this paper,thermal resistance analysis calculation based on a simplified model for this unique radiant heating system analysis is presented with the heat transfer mechanism’s evaluation.The results obtained from thermal resistance analysis calculation and numerical simulation indicate that the thermal resistance analysis method is highly accurate with temperature discrepancies ranging from 0.44℃ to−0.44℃ and a heat flux discrepancy of less than 7.54%,which can meet the requirements of practical engineering applications,suggesting a foundation for the prefabricated radiant heating system.展开更多
Taking a new type of full-fiber crankshaft forging hydraulic press as the research object,an upsetting-bending stroke coordination control is studied to improve crankshaft forming accuracy.A master-slave proportion in...Taking a new type of full-fiber crankshaft forging hydraulic press as the research object,an upsetting-bending stroke coordination control is studied to improve crankshaft forming accuracy.A master-slave proportion integration differentiation(PID)coordination control strategy based on velocity feed-forward is proposed to improve the coordination control accuracy.The structure and working process of the full-fiber crankshaft forging hydraulic press are introduced,and a mathematical model of the upsetting and bending control system are established.The coordination control strategy is verified experimentally.The experimental results show that the maximum tracking error of the coordination control strategy is reduced by 66%compared with the traditional PID controller,and the coordination motion accuracy is improved effectively.展开更多
Using the low-resolution （T31, equivalent to 3.75°× 3.75°） version of the Community Earth System Model （CESM） from the National Center for Atmospheric Research （NCAR）, a global climate simulation ...Using the low-resolution （T31, equivalent to 3.75°× 3.75°） version of the Community Earth System Model （CESM） from the National Center for Atmospheric Research （NCAR）, a global climate simulation was carried out with fixed external forcing factors （1850 Common Era. （C.E.） conditions） for the past 2000 years. Based on the simulated results, spatio-temporal structures of surface air temperature, precipitation and internal variability, such as the E1 Nifio-Southem Oscillation （ENSO）, the Atlantic Multi-decadal Oscilla- tion （AMO）, the Pacific Decadal Oscillation （PDO）, and the North Atlantic Oscillation （NAO）, were compared with reanalysis datasets to evaluate the model performance. The results are as follows： 1） CESM showed a good performance in the long-term simulation and no significant climate drift over the past 2000 years; 2） climatological patterns of global and regional climate changes simulated by the CESM were reasonable compared with the reanalysis datasets; and 3） the CESM simulated internal natural variability of the climate system performs very well. The model not only reproduced the periodicity of ENSO, AMO and PDO events but also the 3-8 years vari- ability of the ENSO. The spatial distribution of the CESM-simulated NAO was also similar to the observed. However, because of weaker total irradiation and greenhouse gas concentration forcing in the simulation than the present, the model performances had some differences from the observations. Generally, the CESM showed a good performance in simulating the global climate and internal natu- ral variability of the climate system. This paves the way for other forced climate simulations for the past 2000 years by using the CESM.展开更多
Lightweight,flexibility,and low thickness are urgent requirements for next-generation high-performance electromagnetic interference(EMI)shielding materials for catering to the demand for smart and wearable electronic ...Lightweight,flexibility,and low thickness are urgent requirements for next-generation high-performance electromagnetic interference(EMI)shielding materials for catering to the demand for smart and wearable electronic devices.Although several efforts have focused on constructing porous and flexible conductive films or aerogels,few studies have achieved a balance in terms of density,thickness,flexibility,and EMI shielding effectiveness(SE).Herein,an ultrathin,lightweight,and flexible carbon nanotube(CNT)buckypaper enhanced using MXenes(Ti3C2Tx)for high-performance EMI shielding is synthesized through a facile electrophoretic deposition process.The obtained Ti3C2Tx@CNT hybrid buckypaper exhibits an outstanding EMI SE of 60.5 dB in the X-band at 100μm.The hybrid buckypaper with an MXene content of 49.4 wt%exhibits an EMI SE of 50.4 dB in the X-band with a thickness of only 15μm,which is 105%higher than that of pristine CNT buckypaper.Furthermore,an average specific SE value of 5.7×10^(4) dB cm^(2) g^(−1) is exhibited in the 5-μm hybrid buckypaper.Thus,this assembly process proves promising for the construction of ultrathin,flexible,and high-performance EMI shielding films for application in electronic devices and wireless communications.展开更多
Objective:To explore the relationship between IL-1β.IL-1Ra gene polymorphism and the occurrence of polycystic ovary syndrome(PCOS) infertility.Methods:A total of 59 PCOS infertility cases visiling the reproductive ce...Objective:To explore the relationship between IL-1β.IL-1Ra gene polymorphism and the occurrence of polycystic ovary syndrome(PCOS) infertility.Methods:A total of 59 PCOS infertility cases visiling the reproductive center of our hospital from Mar.2010 to Mar.2012 and 56 healthy women were selected.ELISA method was used lor the detection of IL-1β.IL-1Ra lewis,and the levels of serum supersensitivity C reaction protein(US-CRP).insulin(FINS),follieule-stimulating hormone(FSH) and fasting blood—glucose(FRG) were detected.PCR analysis technology was adopted to detect the gene polymorphism of the.511 site of IL-1βand the second introne of IL- 1Ra.Results:The levels of IL-1β.IL-1Ra.US-CRP.FINS and FBG in blood scrum of patients in PCOS group were significantly higher than those in control group(P【0.05 or P【0.01).The level of FSH in PCOS group was significantly lower than that in control group(P【0.05).The genotypic frequency of T/T.the 511 site of IL-1βin PCOS group was 42.37%.significantly higher than 1250%in control group 【P【0.01).The frequency of T allele was also significantly higher than that in control group(P【0.01).The genotypic frequency ofⅠ/Ⅴ.the second introne of IL-1Ra in PCOS group was 20.34%,signicianlly higher than 3.57%in control group(P【0.05).The frequency of V allele in PCOS group was significantly higher than that in control group(P【0.05).Conclusions: T allele of the 511 site of IL-1βgene and V allele of the second inlrone of IL-1Ra gene might be the genetic basis of the rising of IL-1β.IL-1Ra and US-CRP levels in blood serum of PCOS patients,and are associated with the infertility occurrence of PCOS patients.展开更多
To improve efficiency, reduce cost, ensure quality effectively, researchers on CNC machining have focused on virtual machine tool, cloud manufacturing, wireless manufacturing. However, low level of information shared ...To improve efficiency, reduce cost, ensure quality effectively, researchers on CNC machining have focused on virtual machine tool, cloud manufacturing, wireless manufacturing. However, low level of information shared among different systems is a common disadvantage. In this paper, a machining database with data evaluation module is set up to ensure integrity and update. An online monitoring system based on internet of things and multi-sensors ＂feel＂ a variety of signal features to ＂percept＂ the state in CNC machining process. A high efficiency and green machining parameters optimization system ＂execute＂ service-oriented manufacturing, intelligent manufacturing and green manufacturing. The intelligent CNC machining system is applied in production. CNC machining database effectively shares and manages process data among different systems. The prediction accuracy of online monitoring system is up to 98.8% by acquiring acceleration and noise in real time. High efficiency and green machining parameters optimization system optimizes the original processing parameters, and the calculation indicates that optimized processing parameters not only improve production efficiency, but also reduce carbon emissions. The application proves that the shared and service-oriented CNC machining system is reliable and effective. This research presents a shared and service-oriented CNC machining system for intelligent manufacturing process.展开更多
基金Project(NB-2020-JG-07)supported by the Research and Engineering Application of Key Technologies for New Building Industrialization Project of China Northwest Architectural Design and Research Institute Co.,Ltd.Project(2023-CXTD-29)supported by the Key Scientific and Technological Innovation Team of Shaanxi Province,ChinaProject supported by the K.C.Wong Education Foundation。
文摘The utilization of prefabricated light modular radiant heating system has demonstrated significant increases in heat transfer efficiency and energy conservation capabilities.Within prefabricated building construction,this new heating method presents an opportunity for the development of comprehensive facilities.The parameters for evaluating the effectiveness of such a system are the upper surface layer’s heat flux and temperature.In this paper,thermal resistance analysis calculation based on a simplified model for this unique radiant heating system analysis is presented with the heat transfer mechanism’s evaluation.The results obtained from thermal resistance analysis calculation and numerical simulation indicate that the thermal resistance analysis method is highly accurate with temperature discrepancies ranging from 0.44℃ to−0.44℃ and a heat flux discrepancy of less than 7.54%,which can meet the requirements of practical engineering applications,suggesting a foundation for the prefabricated radiant heating system.
基金Supported by the National Natural Science Foundation of China(No.51575471)Natural Science Foundation of Hebei Province(No.E2018203028)+2 种基金Open Foundation of the State Key Laboratory of Fluid Power and Mechatronic Systems(No.GZKF-201716)the Key Project of Science and Technology Plan of Higher Education of Hebei Education Department(No.ZD2017077)National Basic Research Program of China(No.2014CB046405)
文摘Taking a new type of full-fiber crankshaft forging hydraulic press as the research object,an upsetting-bending stroke coordination control is studied to improve crankshaft forming accuracy.A master-slave proportion integration differentiation(PID)coordination control strategy based on velocity feed-forward is proposed to improve the coordination control accuracy.The structure and working process of the full-fiber crankshaft forging hydraulic press are introduced,and a mathematical model of the upsetting and bending control system are established.The coordination control strategy is verified experimentally.The experimental results show that the maximum tracking error of the coordination control strategy is reduced by 66%compared with the traditional PID controller,and the coordination motion accuracy is improved effectively.
基金Under the auspices of National Basic Research Program of China(No.2010CB950102)Strategic and Special Frontier Project of Science and Technology of Chinese Academy of Sciences(No.XDA05080800)+3 种基金National Natural Science Foundation of China(No.41371209,41420104002)Special Research Fund for Doctoral Discipline of Higher Education Institutions(No.20133207110015)Natural Science Foundation of Jiangsu Higher Education Institutions(No.14KJA170002)Priority Academic Program Development of Jiangsu Higher Education Institutions(No.164320H101)
文摘Using the low-resolution （T31, equivalent to 3.75°× 3.75°） version of the Community Earth System Model （CESM） from the National Center for Atmospheric Research （NCAR）, a global climate simulation was carried out with fixed external forcing factors （1850 Common Era. （C.E.） conditions） for the past 2000 years. Based on the simulated results, spatio-temporal structures of surface air temperature, precipitation and internal variability, such as the E1 Nifio-Southem Oscillation （ENSO）, the Atlantic Multi-decadal Oscilla- tion （AMO）, the Pacific Decadal Oscillation （PDO）, and the North Atlantic Oscillation （NAO）, were compared with reanalysis datasets to evaluate the model performance. The results are as follows： 1） CESM showed a good performance in the long-term simulation and no significant climate drift over the past 2000 years; 2） climatological patterns of global and regional climate changes simulated by the CESM were reasonable compared with the reanalysis datasets; and 3） the CESM simulated internal natural variability of the climate system performs very well. The model not only reproduced the periodicity of ENSO, AMO and PDO events but also the 3-8 years vari- ability of the ENSO. The spatial distribution of the CESM-simulated NAO was also similar to the observed. However, because of weaker total irradiation and greenhouse gas concentration forcing in the simulation than the present, the model performances had some differences from the observations. Generally, the CESM showed a good performance in simulating the global climate and internal natu- ral variability of the climate system. This paves the way for other forced climate simulations for the past 2000 years by using the CESM.
基金National Natural Science Foundation of China(Grant Nos.52072415,52072306 and 51772335)the Science and Technology Program of Guangzhou(201904010450)Science Foundation of the National Key Laboratory of Science and Technology on Advanced Composites in Special Environments(6142905192509).
文摘Lightweight,flexibility,and low thickness are urgent requirements for next-generation high-performance electromagnetic interference(EMI)shielding materials for catering to the demand for smart and wearable electronic devices.Although several efforts have focused on constructing porous and flexible conductive films or aerogels,few studies have achieved a balance in terms of density,thickness,flexibility,and EMI shielding effectiveness(SE).Herein,an ultrathin,lightweight,and flexible carbon nanotube(CNT)buckypaper enhanced using MXenes(Ti3C2Tx)for high-performance EMI shielding is synthesized through a facile electrophoretic deposition process.The obtained Ti3C2Tx@CNT hybrid buckypaper exhibits an outstanding EMI SE of 60.5 dB in the X-band at 100μm.The hybrid buckypaper with an MXene content of 49.4 wt%exhibits an EMI SE of 50.4 dB in the X-band with a thickness of only 15μm,which is 105%higher than that of pristine CNT buckypaper.Furthermore,an average specific SE value of 5.7×10^(4) dB cm^(2) g^(−1) is exhibited in the 5-μm hybrid buckypaper.Thus,this assembly process proves promising for the construction of ultrathin,flexible,and high-performance EMI shielding films for application in electronic devices and wireless communications.
文摘Objective:To explore the relationship between IL-1β.IL-1Ra gene polymorphism and the occurrence of polycystic ovary syndrome(PCOS) infertility.Methods:A total of 59 PCOS infertility cases visiling the reproductive center of our hospital from Mar.2010 to Mar.2012 and 56 healthy women were selected.ELISA method was used lor the detection of IL-1β.IL-1Ra lewis,and the levels of serum supersensitivity C reaction protein(US-CRP).insulin(FINS),follieule-stimulating hormone(FSH) and fasting blood—glucose(FRG) were detected.PCR analysis technology was adopted to detect the gene polymorphism of the.511 site of IL-1βand the second introne of IL- 1Ra.Results:The levels of IL-1β.IL-1Ra.US-CRP.FINS and FBG in blood scrum of patients in PCOS group were significantly higher than those in control group(P【0.05 or P【0.01).The level of FSH in PCOS group was significantly lower than that in control group(P【0.05).The genotypic frequency of T/T.the 511 site of IL-1βin PCOS group was 42.37%.significantly higher than 1250%in control group 【P【0.01).The frequency of T allele was also significantly higher than that in control group(P【0.01).The genotypic frequency ofⅠ/Ⅴ.the second introne of IL-1Ra in PCOS group was 20.34%,signicianlly higher than 3.57%in control group(P【0.05).The frequency of V allele in PCOS group was significantly higher than that in control group(P【0.05).Conclusions: T allele of the 511 site of IL-1βgene and V allele of the second inlrone of IL-1Ra gene might be the genetic basis of the rising of IL-1β.IL-1Ra and US-CRP levels in blood serum of PCOS patients,and are associated with the infertility occurrence of PCOS patients.
基金Supported by National Defense Basic Scientific Research of China(Grant No.A2120110002)National Science Foundation of China(Grant No.11290144)Major National Science and Technology Special Project of China(Grant Nos.2010ZX04014-052,2010ZX0414-017)
文摘To improve efficiency, reduce cost, ensure quality effectively, researchers on CNC machining have focused on virtual machine tool, cloud manufacturing, wireless manufacturing. However, low level of information shared among different systems is a common disadvantage. In this paper, a machining database with data evaluation module is set up to ensure integrity and update. An online monitoring system based on internet of things and multi-sensors ＂feel＂ a variety of signal features to ＂percept＂ the state in CNC machining process. A high efficiency and green machining parameters optimization system ＂execute＂ service-oriented manufacturing, intelligent manufacturing and green manufacturing. The intelligent CNC machining system is applied in production. CNC machining database effectively shares and manages process data among different systems. The prediction accuracy of online monitoring system is up to 98.8% by acquiring acceleration and noise in real time. High efficiency and green machining parameters optimization system optimizes the original processing parameters, and the calculation indicates that optimized processing parameters not only improve production efficiency, but also reduce carbon emissions. The application proves that the shared and service-oriented CNC machining system is reliable and effective. This research presents a shared and service-oriented CNC machining system for intelligent manufacturing process.
