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
Differential Power Analysis (DPA) is an effective attack method to break the crypto chips and it has been considered to be a threat to security of information system. With analyzing the prin-ciple of resisting DPA,an ...Differential Power Analysis (DPA) is an effective attack method to break the crypto chips and it has been considered to be a threat to security of information system. With analyzing the prin-ciple of resisting DPA,an available countermeasure based on randomization is proposed in this paper. Time delay is inserted in the operation process and random number is precharged to the circuit during the delay time,the normal schedule is disturbed and the power is randomized. Following this meth-odology,a general DPA resistance random precharge architecture is proposed and DES algorithm following this architecture is implemented. This countermeasure is testified to be efficient to resist DPA.展开更多
In an integrated structure low resistance CICC joint, current is conducted by outer cable strands coming into touch with the conductive Cu sole. So it is an important condition for satisfying joint performance that ea...In an integrated structure low resistance CICC joint, current is conducted by outer cable strands coming into touch with the conductive Cu sole. So it is an important condition for satisfying joint performance that each strand of the cable inside the joint is able to come to the outermost by transposition. This paper presents analysis, calculation and figures for the strand transposition. According to the twist procedures of the superconducting cable, the author computed the actual pitch of each stage cable, consecutively computed the projection of each stage cable on the axis of the cable (z axis) and the corresponding twist angle as the z coordinate changes, which is then drawn by AutoCAD. From the results shown in the figures, the minimal cable length, which enables each strand to transpose almost equally to the outermost of the cable in such a length, call be determined as the optimal joint length.展开更多
To confirm resistance and genetic rules of Xikemai 6 against physiological races of wheat stripe rust,physiological races CYR31,CYR32 and CYR33,Su11-4 and V26 were inoculated in Xikemai 6 and Mingxian 169 and their hy...To confirm resistance and genetic rules of Xikemai 6 against physiological races of wheat stripe rust,physiological races CYR31,CYR32 and CYR33,Su11-4 and V26 were inoculated in Xikemai 6 and Mingxian 169 and their hybrid progenies F_1,F_2 and F_3 at adult plant stage on March 2015. The results showed that the resistance of Xikemai 6 against CYR31 was controlled by 2 pairs of dominant genes and a pair of recessive genes; the resistance against CYR32 was controlled by three pairs of dominant resistant genes( two pairs of genes performed cumulative effect); the resistance against CYR33 was controlled by a pair of dominant genes and a pair of recessive genes; the resistance against Su11-4 was controlled by a pair of dominant genes and a pair of recessive genes independently or collaboratively; the resistance against V26 was controlled by a pair of dominant genes independently. Due to good performance of Xikemai 6 in test and production,as well as years of resistance identification and genetic analysis,Xikemai 6 was proved to be an excellent cultivar with good resistance against stripe rust,and the inheritance of its resistance was stable,so Xikemai 6 could be used as a germplasm resource and resistance material with excellent comprehensive character. Molecular marker and localization could be further studied,to provide new resistance parents for disease-resistant breeding of wheat.展开更多
To solve the problem of life estimation of reinforced concrete (RC) members after fire, an analysis is made of the resistance of RC members after fire. On basis of the resistance, the life of RC members after fire i...To solve the problem of life estimation of reinforced concrete (RC) members after fire, an analysis is made of the resistance of RC members after fire. On basis of the resistance, the life of RC members after fire is analyzed by using JC (Jukes and Cantor) method. Then the calculation models for the resistance and the life estimation of RC members after fire are put forward, and an example analysis proves their reliability and accuracy.展开更多
[Objectives]The paper was to evaluate the resistance of indica rice varieties with bacterial blight resistance genes Xa21 and Xa23 under different genetic backgrounds.[Methods]The rice materials with bacterial blight ...[Objectives]The paper was to evaluate the resistance of indica rice varieties with bacterial blight resistance genes Xa21 and Xa23 under different genetic backgrounds.[Methods]The rice materials with bacterial blight resistance genes Xa21 or Xa23 were used as the donors,and those without the genes were used as the receptors.By back crossing,composite crossing and other methods,combined with molecular marker-assisted selection(MAS),the materials with Xa21 or Xa23 gene,and their sister lines with/without Xa21 or Xa23 gene were inoculated with 7 widely used physiological races of Xanthomonas oryzae,and the resistance of the materials to bacterial blight was analyzed.[Results]The proportions of cumulative resistance(HR,R,MR)of rice materials with resistance gene Xa21 were HNA1-4/PXO86(84.62%)>YN24(82.14%)>GD1358(73.08%)>PXO99(67.86%)>GDA2(63.33%)>FuJ(6.67%),indicating that the materials with Xa21 gene had no resistance to bacterial blight induced by strain FuJ,but for other strains,there were still 36.67%-15.38%of the materials susceptible to the disease.The cumulative resistance(HR,R,MR)of the materials with Xa23 gene was over 76%,but there were still 23.02%-15.52%of the materials that had no resistance to the 7 strains.The analysis of variation coefficient of lesion length showed that the resistance of materials with Xa21 or Xa23 genes varied among strains,or the resistance to the same strain varied among materials.Correlation analysis demonstrated that there was significant or extremely significant positive correlation between strain GDA2 or HNA1-4 and other 6 corresponding strains in the materials with Xa21 gene,and there was extremely significant positive correlation between strain YN24,GD1358 or PXO86 and other 6 corresponding strains in the materials with Xa23 gene.Selection of these strains for resistance identification could improve the efficiency of breeding.Analysis of sister lines showed that bacterial blight resistance of Xa21 or Xa23 genes was related to the donor of the materials.Correlation analysis showed that the resistance of the materials with Xa21 gene had extremely significant positive correlation with parents(R=0.5725**),and the resistance of the materials with Xa23 gene had significant positive correlation with parents(R=0.2212*).[Conclusions]The study provides the reference for molecular resistance breeding of bacterial blight.展开更多
The arc erosion under medium direct currents in the argon flow was tested on tungsten-copper(W-Cu) contacts which were processed by hot extrusion and heat treatment. The scanning electron microscopy(SEM) and trans...The arc erosion under medium direct currents in the argon flow was tested on tungsten-copper(W-Cu) contacts which were processed by hot extrusion and heat treatment. The scanning electron microscopy(SEM) and transmission electron microscopy(TEM) were used to study the microstructure of the W-Cu powders and compacts. The contact resistance, arcing energy, and arcing time were continuously measured by JF04C contact materials test system. Changes in tungsten-copper contact surface were observed by SEM. The test results showed that the arcing time and arcing energy all increase with current and voltage, but the changes of average contact resistance are more complicated. For a short arcing time, the average contact resistance decreases with increasing current due to the vaporization of Cu. However, for a longer arcing time, it slightly increases due to the formation of high resistant films, compound copper tungsten. The formation of compound copper tungsten was confirmed by the increased Rc kept in the range from 1.1 to 1.6 mΩ. The compound copper tungsten is first exposed with a tungsten and copper-rich surface, and then totally exposed due to evaporation of copper from the surface. At last a stabilized surface is created and the crystals decrease from 8 μm to 2 μm caused by the arc erosion.展开更多
A concept design, named integrated suction foundation, is proposed for a tension leg platform(TLP) in deep ocean. The most important improvement in comparing with the traditional one is that a pressure-resistant sto...A concept design, named integrated suction foundation, is proposed for a tension leg platform(TLP) in deep ocean. The most important improvement in comparing with the traditional one is that a pressure-resistant storage module is designed. It utilizes the high hydrostatic pressure in deep ocean to drive water into the module to generate negative pressure for bucket suction. This work aims to further approve the feasibility of the concept design in the aspect of penetration installation and the uplift force in-place. Seepage is generated during suction penetration, and can have both positive and negative effects on penetration process. To study the effect of seepage on the penetration process of the integrated suction foundation, finite element analysis(FEA) is carried out in this work. In particular, an improved methodology to calculate the penetration resistance is proposed for the integrated suction foundation with respect to the reduction factor of penetration resistance. The maximum allowable negative pressure during suction penetration is calculated with the critical hydraulic gradient method through FEA. The simulation results of the penetration process show that the integrated suction foundation can be installed safely. Moreover, the uplift resistance of the integrated suction foundation is calculated and the feasibility of the integrated suction foundation working on-site is verified. In all, the analysis in this work further approves the feasibility of the integrated suction foundation for TLPs in deep ocean applications.展开更多
Condensation is a phase-change heat-transfer phenomenon crucial in many industries involving latent heat release and mass transfer.Shell-and-tube condensers are essential contributors to the condensation process,and t...Condensation is a phase-change heat-transfer phenomenon crucial in many industries involving latent heat release and mass transfer.Shell-and-tube condensers are essential contributors to the condensation process,and their tube bundles serve as a substrate.Here,the thermal-hydraulic characteristics of condensation in a longitudinal-flow shell-and-tube condenser were investigated numerically.The shell-side longitudinal-flow condensation on the horizontal tube bundles was studied considering inlet flow rate,overheating temperature,and non-condensable gases.Related pressure drops and heat transfer coefficients were subdivided into several components to provide further insights.Two-phase interface behavior analyses were conducted to demonstrate the outcomes with respect to the non-condensable gas layer,vapor quality,and non-condensable gas type.Based on the thorough quantitative analyses outlined above,the thermal resistance of the condensation on the horizontal tube bundle was investigated.The thermal resistance outside the tube was found to dominate the condensation process.Finally,hexagon clamping baffles(HCBs)were introduced as a novel solution to impair condensate boundary layers and provide perturbations to intensify condensation heat transfer.The results revealed that the HCBs enhanced the total heat transfer coefficients by 8.1%–40.7%while reducing the critical overheating temperature and the threshold ratio between sensible and latent heat.展开更多
Pelvic fracture is among the most complicated fractures in traumatic orthopedics,with high mortality and morbidity rates.The main difficulty associated with the reduction surgery is significant muscle resistance.It th...Pelvic fracture is among the most complicated fractures in traumatic orthopedics,with high mortality and morbidity rates.The main difficulty associated with the reduction surgery is significant muscle resistance.It then becomes necessary to decrease the reduction force against this strong muscle resistance,for improving surgical safety.Here,we propose a novel traction method for decreasing the reduction force during pelvic reduction,and investigate the performance of the elastic traction method on decreasing the reduction force using experimental tests and simulation-based analyses.From the experimental results,the reduction force decreased by 59.2%when 10 kg of elastic traction was applied.We also establish a musculoskeletal model of the pelvic fracture reduction,for analyzing the muscle resistance and the optimal traction force applied in reduction surgeries.The elastic traction method can counteract the muscle resistance increase in the non-traction direction owing to its flexibility.We conclude that the optimal traction force applied should be in the 10–15 kg range,and recommend adopting a dynamic traction strategy rather than continuous traction in clinical settings.Elastic traction is very promising for various surgeries that require traction,including pelvic reduction.It significantly reduces force,which can significantly reduce the physical exertion of the operating surgeon,the possibility of additional injuries to the operated patient,and promotes robot-assisted reduction surgeries.展开更多
Objective To evaluate the predictive value and impact for the index of microcirculatory resistance(IMR)in myocardial infarction(MI)patients with elective percutaneous coronary intervention(PCI)for treating coronary ar...Objective To evaluate the predictive value and impact for the index of microcirculatory resistance(IMR)in myocardial infarction(MI)patients with elective percutaneous coronary intervention(PCI)for treating coronary artery occlusion.Methods A total of 34 patients with STEMI or non-STEMI treated after 12h time window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.
文摘Differential Power Analysis (DPA) is an effective attack method to break the crypto chips and it has been considered to be a threat to security of information system. With analyzing the prin-ciple of resisting DPA,an available countermeasure based on randomization is proposed in this paper. Time delay is inserted in the operation process and random number is precharged to the circuit during the delay time,the normal schedule is disturbed and the power is randomized. Following this meth-odology,a general DPA resistance random precharge architecture is proposed and DES algorithm following this architecture is implemented. This countermeasure is testified to be efficient to resist DPA.
文摘In an integrated structure low resistance CICC joint, current is conducted by outer cable strands coming into touch with the conductive Cu sole. So it is an important condition for satisfying joint performance that each strand of the cable inside the joint is able to come to the outermost by transposition. This paper presents analysis, calculation and figures for the strand transposition. According to the twist procedures of the superconducting cable, the author computed the actual pitch of each stage cable, consecutively computed the projection of each stage cable on the axis of the cable (z axis) and the corresponding twist angle as the z coordinate changes, which is then drawn by AutoCAD. From the results shown in the figures, the minimal cable length, which enables each strand to transpose almost equally to the outermost of the cable in such a length, call be determined as the optimal joint length.
基金Supported by Key Research Project of Wheat Breeding in Sichuan Province(2011NZ0098-3-18)
文摘To confirm resistance and genetic rules of Xikemai 6 against physiological races of wheat stripe rust,physiological races CYR31,CYR32 and CYR33,Su11-4 and V26 were inoculated in Xikemai 6 and Mingxian 169 and their hybrid progenies F_1,F_2 and F_3 at adult plant stage on March 2015. The results showed that the resistance of Xikemai 6 against CYR31 was controlled by 2 pairs of dominant genes and a pair of recessive genes; the resistance against CYR32 was controlled by three pairs of dominant resistant genes( two pairs of genes performed cumulative effect); the resistance against CYR33 was controlled by a pair of dominant genes and a pair of recessive genes; the resistance against Su11-4 was controlled by a pair of dominant genes and a pair of recessive genes independently or collaboratively; the resistance against V26 was controlled by a pair of dominant genes independently. Due to good performance of Xikemai 6 in test and production,as well as years of resistance identification and genetic analysis,Xikemai 6 was proved to be an excellent cultivar with good resistance against stripe rust,and the inheritance of its resistance was stable,so Xikemai 6 could be used as a germplasm resource and resistance material with excellent comprehensive character. Molecular marker and localization could be further studied,to provide new resistance parents for disease-resistant breeding of wheat.
文摘To solve the problem of life estimation of reinforced concrete (RC) members after fire, an analysis is made of the resistance of RC members after fire. On basis of the resistance, the life of RC members after fire is analyzed by using JC (Jukes and Cantor) method. Then the calculation models for the resistance and the life estimation of RC members after fire are put forward, and an example analysis proves their reliability and accuracy.
基金Supported by National Natural Science Foundation of China(U19A2025)Strategic Priority Research Program of Chinese Academy of Science(XDA24030201)。
文摘[Objectives]The paper was to evaluate the resistance of indica rice varieties with bacterial blight resistance genes Xa21 and Xa23 under different genetic backgrounds.[Methods]The rice materials with bacterial blight resistance genes Xa21 or Xa23 were used as the donors,and those without the genes were used as the receptors.By back crossing,composite crossing and other methods,combined with molecular marker-assisted selection(MAS),the materials with Xa21 or Xa23 gene,and their sister lines with/without Xa21 or Xa23 gene were inoculated with 7 widely used physiological races of Xanthomonas oryzae,and the resistance of the materials to bacterial blight was analyzed.[Results]The proportions of cumulative resistance(HR,R,MR)of rice materials with resistance gene Xa21 were HNA1-4/PXO86(84.62%)>YN24(82.14%)>GD1358(73.08%)>PXO99(67.86%)>GDA2(63.33%)>FuJ(6.67%),indicating that the materials with Xa21 gene had no resistance to bacterial blight induced by strain FuJ,but for other strains,there were still 36.67%-15.38%of the materials susceptible to the disease.The cumulative resistance(HR,R,MR)of the materials with Xa23 gene was over 76%,but there were still 23.02%-15.52%of the materials that had no resistance to the 7 strains.The analysis of variation coefficient of lesion length showed that the resistance of materials with Xa21 or Xa23 genes varied among strains,or the resistance to the same strain varied among materials.Correlation analysis demonstrated that there was significant or extremely significant positive correlation between strain GDA2 or HNA1-4 and other 6 corresponding strains in the materials with Xa21 gene,and there was extremely significant positive correlation between strain YN24,GD1358 or PXO86 and other 6 corresponding strains in the materials with Xa23 gene.Selection of these strains for resistance identification could improve the efficiency of breeding.Analysis of sister lines showed that bacterial blight resistance of Xa21 or Xa23 genes was related to the donor of the materials.Correlation analysis showed that the resistance of the materials with Xa21 gene had extremely significant positive correlation with parents(R=0.5725**),and the resistance of the materials with Xa23 gene had significant positive correlation with parents(R=0.2212*).[Conclusions]The study provides the reference for molecular resistance breeding of bacterial blight.
文摘The arc erosion under medium direct currents in the argon flow was tested on tungsten-copper(W-Cu) contacts which were processed by hot extrusion and heat treatment. The scanning electron microscopy(SEM) and transmission electron microscopy(TEM) were used to study the microstructure of the W-Cu powders and compacts. The contact resistance, arcing energy, and arcing time were continuously measured by JF04C contact materials test system. Changes in tungsten-copper contact surface were observed by SEM. The test results showed that the arcing time and arcing energy all increase with current and voltage, but the changes of average contact resistance are more complicated. For a short arcing time, the average contact resistance decreases with increasing current due to the vaporization of Cu. However, for a longer arcing time, it slightly increases due to the formation of high resistant films, compound copper tungsten. The formation of compound copper tungsten was confirmed by the increased Rc kept in the range from 1.1 to 1.6 mΩ. The compound copper tungsten is first exposed with a tungsten and copper-rich surface, and then totally exposed due to evaporation of copper from the surface. At last a stabilized surface is created and the crystals decrease from 8 μm to 2 μm caused by the arc erosion.
基金financially supported by the National Basic Key Research Program of China(973 Program,Grant No.2014CB46804)the Tianjin Research Program of Application Foundation and Advanced Technology(Grant No.15JCYBJC21700)
文摘A concept design, named integrated suction foundation, is proposed for a tension leg platform(TLP) in deep ocean. The most important improvement in comparing with the traditional one is that a pressure-resistant storage module is designed. It utilizes the high hydrostatic pressure in deep ocean to drive water into the module to generate negative pressure for bucket suction. This work aims to further approve the feasibility of the concept design in the aspect of penetration installation and the uplift force in-place. Seepage is generated during suction penetration, and can have both positive and negative effects on penetration process. To study the effect of seepage on the penetration process of the integrated suction foundation, finite element analysis(FEA) is carried out in this work. In particular, an improved methodology to calculate the penetration resistance is proposed for the integrated suction foundation with respect to the reduction factor of penetration resistance. The maximum allowable negative pressure during suction penetration is calculated with the critical hydraulic gradient method through FEA. The simulation results of the penetration process show that the integrated suction foundation can be installed safely. Moreover, the uplift resistance of the integrated suction foundation is calculated and the feasibility of the integrated suction foundation working on-site is verified. In all, the analysis in this work further approves the feasibility of the integrated suction foundation for TLPs in deep ocean applications.
基金financial support for this work provided by Natural Science Foundation of China(No.51876146)the Excellent Youth Foundation of Hubei Scientific Committee(No.2019CFA082)the Opening Funds of the Key Lab on Steam Power System(TPL2018B01)。
文摘Condensation is a phase-change heat-transfer phenomenon crucial in many industries involving latent heat release and mass transfer.Shell-and-tube condensers are essential contributors to the condensation process,and their tube bundles serve as a substrate.Here,the thermal-hydraulic characteristics of condensation in a longitudinal-flow shell-and-tube condenser were investigated numerically.The shell-side longitudinal-flow condensation on the horizontal tube bundles was studied considering inlet flow rate,overheating temperature,and non-condensable gases.Related pressure drops and heat transfer coefficients were subdivided into several components to provide further insights.Two-phase interface behavior analyses were conducted to demonstrate the outcomes with respect to the non-condensable gas layer,vapor quality,and non-condensable gas type.Based on the thorough quantitative analyses outlined above,the thermal resistance of the condensation on the horizontal tube bundle was investigated.The thermal resistance outside the tube was found to dominate the condensation process.Finally,hexagon clamping baffles(HCBs)were introduced as a novel solution to impair condensate boundary layers and provide perturbations to intensify condensation heat transfer.The results revealed that the HCBs enhanced the total heat transfer coefficients by 8.1%–40.7%while reducing the critical overheating temperature and the threshold ratio between sensible and latent heat.
基金This work was supported by Key research and development plan of the Ministry of science and technology of China[2019YFC0118002]National Natural Science Foundation(NSFC)Grant of China[61871019]+1 种基金Beijing science and technology project[Z18110001918024]Natural Science Foundation of Beijing[19L2011].
文摘Pelvic fracture is among the most complicated fractures in traumatic orthopedics,with high mortality and morbidity rates.The main difficulty associated with the reduction surgery is significant muscle resistance.It then becomes necessary to decrease the reduction force against this strong muscle resistance,for improving surgical safety.Here,we propose a novel traction method for decreasing the reduction force during pelvic reduction,and investigate the performance of the elastic traction method on decreasing the reduction force using experimental tests and simulation-based analyses.From the experimental results,the reduction force decreased by 59.2%when 10 kg of elastic traction was applied.We also establish a musculoskeletal model of the pelvic fracture reduction,for analyzing the muscle resistance and the optimal traction force applied in reduction surgeries.The elastic traction method can counteract the muscle resistance increase in the non-traction direction owing to its flexibility.We conclude that the optimal traction force applied should be in the 10–15 kg range,and recommend adopting a dynamic traction strategy rather than continuous traction in clinical settings.Elastic traction is very promising for various surgeries that require traction,including pelvic reduction.It significantly reduces force,which can significantly reduce the physical exertion of the operating surgeon,the possibility of additional injuries to the operated patient,and promotes robot-assisted reduction surgeries.
文摘Objective To evaluate the predictive value and impact for the index of microcirculatory resistance(IMR)in myocardial infarction(MI)patients with elective percutaneous coronary intervention(PCI)for treating coronary artery occlusion.Methods A total of 34 patients with STEMI or non-STEMI treated after 12h time window