There are always some local damages in spatial steel structures induced by strong earthquakes, such as welding cracks of steel nodes,anchor loose of supports etc.If these local damages of spatial steel structures occu...There are always some local damages in spatial steel structures induced by strong earthquakes, such as welding cracks of steel nodes,anchor loose of supports etc.If these local damages of spatial steel structures occur,there will be serious dangers to the structural safety.In order to detect the position of local damage under earthquake quickly and accurately,the method of support damage diagnosis of spatial steel structures under earthquakes is studied by using wavelet packet decomposition,data fusion and cluster analysis.Furthermore,a scale model of spatial steel structure was tested on a seismic simulation shaking table to detect the position of damaged support.Results show that the damaged support position can be detected accurately by using the method proposed in this paper,which has practical applications to the damage detection of spatial steel structures.展开更多
Objective: Individual differences in the sensitivity to pain and the factors that may contribute to these differences are well studied. Nevertheless, there is no single test that can reliably classify subjects as bein...Objective: Individual differences in the sensitivity to pain and the factors that may contribute to these differences are well studied. Nevertheless, there is no single test that can reliably classify subjects as being sensitive or insensitive to pain. Methods: In the present study, hierarchical clustering and K-means cluster analysis was used to identify subgroups among 191 healthy subjects (105 females, 86 males) according to their sensitivity to pain. Group determination was based on the subjects’ response to experimental noxious stimuli of heat (pain intensity), cold (cold pain threshold, tolerance, and intensity), and conditioned pain modulation (CPM, tested by co-administering repeated short painful heat stimuli and a conditioning tonic cold pain stimulation). In addition, in order to determine if the subjects in these subgroups differed on personality traits scores on Cloninger’s Tridimensional Personality Questionnaire (TPQ, outcome measure) for the three dimensions of personality: Novelty Seeking (NS);Harm Avoidance (HA);and Reward Dependence (RD) were calculated. Results: Based on pain scores, subjects were grouped as low pain (57%) with a low level of sensitivity in pain parameters, or high pain (43%) cluster members. The high pain had significant higher scores of HA (p = 0.05) and RD (p = 0.05) than the low pain group. Conclusions: This method of sub-grouping may be useful for identifying the mechanisms underlying individual variability in the sensitivity to pain and may point to groups at risk for experiencing high levels of clinical pain.展开更多
Accurate test effectiveness estimation for analogue and mixed-signal Systems on a Chip (SoCs) is currently prohibitive in the design environment. One of the factors that sky rockets fault simulation costs is the numbe...Accurate test effectiveness estimation for analogue and mixed-signal Systems on a Chip (SoCs) is currently prohibitive in the design environment. One of the factors that sky rockets fault simulation costs is the number of structural faults which need to be simulated at circuit-level. The purpose of this paper is to propose a novel fault list compression technique by defining a stratified fault list, build with a set of “representative” faults, one per stratum. Criteria to partition the fault list in strata, and to identify representative faults are presented and discussed. A fault representativeness metric is proposed, based on an error probability. The proposed methodology allows different tradeoffs between fault list compression and fault representation accuracy. These tradeoffs may be optimized for each test preparation phase. The fault representativeness vs. fault list compression tradeoff is evaluated with an industrial case study—a DC-DC (switched buck converter). Although the methodology is presented in this paper using a very simple fault model, it may be easily extended to be used with more elaborate fault models. The proposed technique is a significant contribution to make mixed-signal fault simulation cost-effective as part of the production test preparation.展开更多
A design for an air-cooled test tube, with a series of modular and movable rings (cylindrical “crystallization comb”), installed in a laboratory crucible furnace is presented. The setup allows easy regulation simult...A design for an air-cooled test tube, with a series of modular and movable rings (cylindrical “crystallization comb”), installed in a laboratory crucible furnace is presented. The setup allows easy regulation simultaneous crystallization tests of a series of different crystallization rates in several columns (matrix) of test tubes, enabling fast studies of obtaining crystals. This low-budget, portable device (i.e. adjustable airstream with more simple control options), can also be applied in tube and chamber furnaces. The relations between the crystallization rate and parameters of air-cooled test tube are given and numerically analyzed.展开更多
Synchrotron radiation(SR) X-ray has significant potential for medical applications. However, the mechanisms underlying the effects of SR X-ray on biological tissues remain unclear. Because increasing evidence has indi...Synchrotron radiation(SR) X-ray has significant potential for medical applications. However, the mechanisms underlying the effects of SR X-ray on biological tissues remain unclear. Because increasing evidence has indicated critical roles of cluster of differentiation 38(CD38) in various cellular functions and cell survival, in this study we used rodent testes as a model to determine the effects of SR X-ray irradiation on the CD38 level of the testes. We found that SR X-ray irradiation led to a significant increase in the CD38 level of rodent testes one day after the irradiation. In contrast, the SR X-ray irradiation did not produce a significant increase in the CD38 level of the testes from the rats that were administered with the antioxidant N-acetyl cysteine, thus suggesting that oxidative stress plays a significant role in the SR X-ray irradiation-induced increase in the CD38 levels. Our study has also provided evidence suggesting that poly(ADP-ribose) polymerase(PARP) activity is not involved in the SR X-ray irradiation-produced effect on the CD38 levels. Collectively, this study has provided first in vivo evidence indicating that CD38 levels can be increased by ionizing radiation, in which oxidative stress plays an important role. Because oxidative stress occurs in ionizing radiation as well as such diseases as cerebral ischemia and Parkinson's disease, oxidative stress may produce pathological effects by inducing increased CD38 levels.展开更多
基金supported by the National Science and Technology Support Program Subproject Foundation of China(2006BAJ13B03)
文摘There are always some local damages in spatial steel structures induced by strong earthquakes, such as welding cracks of steel nodes,anchor loose of supports etc.If these local damages of spatial steel structures occur,there will be serious dangers to the structural safety.In order to detect the position of local damage under earthquake quickly and accurately,the method of support damage diagnosis of spatial steel structures under earthquakes is studied by using wavelet packet decomposition,data fusion and cluster analysis.Furthermore,a scale model of spatial steel structure was tested on a seismic simulation shaking table to detect the position of damaged support.Results show that the damaged support position can be detected accurately by using the method proposed in this paper,which has practical applications to the damage detection of spatial steel structures.
文摘Objective: Individual differences in the sensitivity to pain and the factors that may contribute to these differences are well studied. Nevertheless, there is no single test that can reliably classify subjects as being sensitive or insensitive to pain. Methods: In the present study, hierarchical clustering and K-means cluster analysis was used to identify subgroups among 191 healthy subjects (105 females, 86 males) according to their sensitivity to pain. Group determination was based on the subjects’ response to experimental noxious stimuli of heat (pain intensity), cold (cold pain threshold, tolerance, and intensity), and conditioned pain modulation (CPM, tested by co-administering repeated short painful heat stimuli and a conditioning tonic cold pain stimulation). In addition, in order to determine if the subjects in these subgroups differed on personality traits scores on Cloninger’s Tridimensional Personality Questionnaire (TPQ, outcome measure) for the three dimensions of personality: Novelty Seeking (NS);Harm Avoidance (HA);and Reward Dependence (RD) were calculated. Results: Based on pain scores, subjects were grouped as low pain (57%) with a low level of sensitivity in pain parameters, or high pain (43%) cluster members. The high pain had significant higher scores of HA (p = 0.05) and RD (p = 0.05) than the low pain group. Conclusions: This method of sub-grouping may be useful for identifying the mechanisms underlying individual variability in the sensitivity to pain and may point to groups at risk for experiencing high levels of clinical pain.
文摘Accurate test effectiveness estimation for analogue and mixed-signal Systems on a Chip (SoCs) is currently prohibitive in the design environment. One of the factors that sky rockets fault simulation costs is the number of structural faults which need to be simulated at circuit-level. The purpose of this paper is to propose a novel fault list compression technique by defining a stratified fault list, build with a set of “representative” faults, one per stratum. Criteria to partition the fault list in strata, and to identify representative faults are presented and discussed. A fault representativeness metric is proposed, based on an error probability. The proposed methodology allows different tradeoffs between fault list compression and fault representation accuracy. These tradeoffs may be optimized for each test preparation phase. The fault representativeness vs. fault list compression tradeoff is evaluated with an industrial case study—a DC-DC (switched buck converter). Although the methodology is presented in this paper using a very simple fault model, it may be easily extended to be used with more elaborate fault models. The proposed technique is a significant contribution to make mixed-signal fault simulation cost-effective as part of the production test preparation.
文摘A design for an air-cooled test tube, with a series of modular and movable rings (cylindrical “crystallization comb”), installed in a laboratory crucible furnace is presented. The setup allows easy regulation simultaneous crystallization tests of a series of different crystallization rates in several columns (matrix) of test tubes, enabling fast studies of obtaining crystals. This low-budget, portable device (i.e. adjustable airstream with more simple control options), can also be applied in tube and chamber furnaces. The relations between the crystallization rate and parameters of air-cooled test tube are given and numerically analyzed.
基金the National Basic Research Program (973) of China(No.2010CB834306)the National Natural Science Foundation of China(No.81171098)
文摘Synchrotron radiation(SR) X-ray has significant potential for medical applications. However, the mechanisms underlying the effects of SR X-ray on biological tissues remain unclear. Because increasing evidence has indicated critical roles of cluster of differentiation 38(CD38) in various cellular functions and cell survival, in this study we used rodent testes as a model to determine the effects of SR X-ray irradiation on the CD38 level of the testes. We found that SR X-ray irradiation led to a significant increase in the CD38 level of rodent testes one day after the irradiation. In contrast, the SR X-ray irradiation did not produce a significant increase in the CD38 level of the testes from the rats that were administered with the antioxidant N-acetyl cysteine, thus suggesting that oxidative stress plays a significant role in the SR X-ray irradiation-induced increase in the CD38 levels. Our study has also provided evidence suggesting that poly(ADP-ribose) polymerase(PARP) activity is not involved in the SR X-ray irradiation-produced effect on the CD38 levels. Collectively, this study has provided first in vivo evidence indicating that CD38 levels can be increased by ionizing radiation, in which oxidative stress plays an important role. Because oxidative stress occurs in ionizing radiation as well as such diseases as cerebral ischemia and Parkinson's disease, oxidative stress may produce pathological effects by inducing increased CD38 levels.