This paper considers a model of a recursive neuron whose circuit the author finds interesting, not because of its financial possibility, but because of its surprising electrical behavior. Below, a recursive neuron is ...This paper considers a model of a recursive neuron whose circuit the author finds interesting, not because of its financial possibility, but because of its surprising electrical behavior. Below, a recursive neuron is modeled with excitatory and inhibitory triggering, and simulated using Win Spice. This model is shown to be capable of controlled toggling, and so promises energy-efficient, massively parallel computing.展开更多
For training the present Neural Network(NN)models,the standard technique is to utilize decaying Learning Rates(LR).While the majority of these techniques commence with a large LR,they will decay multiple times over ti...For training the present Neural Network(NN)models,the standard technique is to utilize decaying Learning Rates(LR).While the majority of these techniques commence with a large LR,they will decay multiple times over time.Decaying has been proved to enhance generalization as well as optimization.Other parameters,such as the network’s size,the number of hidden layers,drop-outs to avoid overfitting,batch size,and so on,are solely based on heuristics.This work has proposed Adaptive Teaching Learning Based(ATLB)Heuristic to identify the optimal hyperparameters for diverse networks.Here we consider three architec-tures Recurrent Neural Networks(RNN),Long Short Term Memory(LSTM),Bidirectional Long Short Term Memory(BiLSTM)of Deep Neural Networks for classification.The evaluation of the proposed ATLB is done through the various learning rate schedulers Cyclical Learning Rate(CLR),Hyperbolic Tangent Decay(HTD),and Toggle between Hyperbolic Tangent Decay and Triangular mode with Restarts(T-HTR)techniques.Experimental results have shown the performance improvement on the 20Newsgroup,Reuters Newswire and IMDB dataset.展开更多
After nearly a decade of application and investigation, a motion amplification device with viscous dampers for energy dissipation has been recognized as an effective solution to mitigate wind or seismic excitation, es...After nearly a decade of application and investigation, a motion amplification device with viscous dampers for energy dissipation has been recognized as an effective solution to mitigate wind or seismic excitation, especially for stiff structural systems. As a result of compensation of amplified motion, it has been proved that the efficiency of viscous damper largely depends on the motion amplification device configuration, particularly for device stiflhess. In this paper, a ＂scissor-jack＂ type of motion amplification device, called a ＂toggle brace damper＂ system, is studied. It is demonstrated that the efficiency of such a device reflected by its amplification factor is not merely a function of its geometric configuration, but is highly dependent on the support elements＇ stiffness as well, similar to the mechanism of a leverage arm. Accordingly, a mathematical model in terms of complex modulus of the viscous damper with consideration of the support brace＇s stiffness is established. The results indicate that the efficiency of the motion amplification device with viscous dampers significantly depends on the stiffness of the support elements. Other parameters, such as toggle brace configuration and damping values of the viscous damper, are studied and compared. As an application example, numerical analyses are conducted to study the dynamic performance of a 39-story office tower installed with toggle brace dampers constructed on soft soil in a reclaimed area, under a combined effect of the vortex shedding of an adjacent existing 52-story building and earthquakes. The results show that viscous dampers with a motion amplification system using a properly designed toggle brace device proved to be an effective solution to alleviate the external excitations.展开更多
Jaw crusher is a kind of machine widely used in mining and aggregates industry,but it still has some shortcom- ings,such as liners wear,terrible power draw etc.The lack of research on material flow strongly limits the...Jaw crusher is a kind of machine widely used in mining and aggregates industry,but it still has some shortcom- ings,such as liners wear,terrible power draw etc.The lack of research on material flow strongly limits the design improvement. The size reduction of the jaw crusher relies on the moving jaw movement that is a kind of complicated swing.Based on the move- ment analysis of the moving jaw and the single particle breakage characters,the material flow is analyzed.The measure of the breakage force is carried out.Material flow analysis is partly confirmed by the experimental results and some new information is also learned from the crushing force distribution.The job on the material flow will be helpful to the jaw crusher design improve- ment.展开更多
In this research, a fast methodology to calculate the exact value of the average dynamic power consumption for CMOS combinational logic circuits is developed. The delay model used is the unit-delay model where all gat...In this research, a fast methodology to calculate the exact value of the average dynamic power consumption for CMOS combinational logic circuits is developed. The delay model used is the unit-delay model where all gates have the same propagation delay. The main advantages of this method over other techniques are its accuracy, as it is deterministic and it requires less computational effort compared to exhaustive simulation approaches. The methodology uses the Logic Pictures concept for obtaining the nodes’ toggle rates. The proposed method is applied to well-known circuits and the results are compared to exhaustive simulation and Monte Carlosimulation methods.展开更多
By means of total energy calculations within the framework of the local density approximation (LDA), the interactions between a silicon Si(001) surface and a scanning probe are investigated. The tip of the probe, comp...By means of total energy calculations within the framework of the local density approximation (LDA), the interactions between a silicon Si(001) surface and a scanning probe are investigated. The tip of the probe, comprising 4 Si atoms scans along the dimer lines above an asymmetric p(2 × 1) surface, at a distance where the chemical interaction between tip-surface is dominant and responsible for image resolution. At that distance, the tip causes the dimer to toggle when it scans above the lower atom of a dimer. The toggled dimers create an alternating pattern, where the immediately adjacent neighbours of a toggled dimer remain unchanged. After the tip has fully scanned across the p(2 × 1) surface, causes the dimers to arrange in a p(2 × 2) reconstruction, reproducing the images obtained in scanning probe experiments. Our modelling methodology includes simulations that reveal the energy input required to overcome the barrier to the onset of dimer toggling. The results show that the energy input to overcome this barrier is lower for the p(2 × 1) surface than that for the p(2 × 2) or c(4 × 2) surfaces.展开更多
Taking the famous genetic toggle switch as an example,we numerically investigated the effect of noise on bistability.We found that extrinsic noise resulting from stochastic fluctuations in synthesis and degradation ra...Taking the famous genetic toggle switch as an example,we numerically investigated the effect of noise on bistability.We found that extrinsic noise resulting from stochastic fluctuations in synthesis and degradation rates and from the environmental fluctuation in gene regulatory processes can induce coherent switch,and that there is an optimal noise intensity such that the noise not only can induce this switch,but also can amplify a weak input signal.In addition,we found that the intrinsic noise introduced through the Poisson τ-leap algorithm cannot induce such a switch.展开更多
Background:Reports on the efficacy of modifications to the thread design of pedicle screws are scarce.The aim of the study was to investigate initial and early fixation of pedicle screws with a plasma-sprayed titanium...Background:Reports on the efficacy of modifications to the thread design of pedicle screws are scarce.The aim of the study was to investigate initial and early fixation of pedicle screws with a plasma-sprayed titanium coating and dual pitch in the pedicle region(dual pitch titanium-coated pedicle screw[DPTCPS])in a polyetheretherketone(PEEK)rod semi-rigid fixation system.Methods:Fifty-four sheep spine specimens and 64 sheep were used to investigate initial(“0-week”controls)and early(postoperative 6 months)fixation,respectively.Sheep were divided into dual pitch pedicle screw(DPPS),standard pitch pedicle screw(SPPS),DPTCPS,and standard pitch titanium-coated pedicle screw(SPTCPS)groups.Specimens/sheep were instrumented with four screws and two rods.Biomechanical evaluations were performed,and histology at the implant-bone interface was investigated.Results:At 0-week,mean axial pull-out strength was significantly higher for the DPTCPS and SPTCPS than the SPPS(557.0±25.2 vs.459.1±19.1 N,t=3.61,P<0.05;622.6±25.2 vs.459.1±19.1 N,t=3.43,P<0.05).On toggle-testing,the DPTCPS was significantly more resistant than the SPPS and SPTCPS(343.4±16.5 vs.237.5±12.9 N,t=3.52,P<0.05;343.4±16.5 vs.289.9±12.8 N,t=3.12,P<0.05;124.7±13.5 vs.41.9±4.3 cycles,t=2.18,P<0.05;124.7±13.5 vs.79.5±11.8 cycles,t=2.76,P<0.05).On cyclic loading,maximum displacement was significantly lower for the DPTCPS than the SPPS and SPTCPS(1.8±0.13 vs.3.76±0.19 mm,t=2.29,P<0.05;1.8±0.13 vs.2.46±10.20 mm,t=2.69,P<0.05).At post-operative 6 months,mean axial pull-out strength was significantly higher for the DPTCPS and SPTCPS than the SPPS(908.4±33.6 vs.646.5±59.4 N,t=3.34,P<0.05;925.9±53.9 vs.646.5±59.4 N,t=3.37,P<0.05).On toggle-testing,the DPTCPS was significantly more resistant than the SPPS and SPTCPS(496.9±17.9 vs.370.3±16.4 N,t=2.86,P<0.05;496.9±17.9 vs.414.1±12.8 N,t=2.74,P<0.05;249.1±11.0 vs.149.9±11.1 cycles,t=2.54,P<0.05;249.1±11.0 vs.199.8±7.2 cycles,t=2.61,P<0.05).On cyclic loading,maximum displacement was significantly lower for the DPTCPS than the SPPS and SPTCPS(0.96±0.11 vs.2.39±0.14 mm,t=2.57,P<0.05;0.96±0.11 vs.1.82±0.12 mm,t=2.73,P<0.05).Resistance to toggle testing(370.3±16.4 vs.414.1±12.8 N,t=3.29,P<0.05;149.9±11.1 vs.199.8±7.2 cycles,t=2.97,P<0.05)was significantly lower and maximum displacement in cyclic loading(2.39±0.14 vs.1.82±0.12 mm;t=3.06,P<0.05)was significantly higher for the SPTCPS than the DPTCPS.Bone-to-implant contact was significantly increased for the DPTCPS compared to the SPPS(58.3%±7.0%vs.36.5%±4.4%,t=2.74,P<0.05);there was no inflammatory reaction or degradation of coated particles.Conclusion:DPTCPSs might have stronger initial and early fixation in a PEEK rod semi-rigid fixation system.展开更多
Masking is one of the most commonly used Side-Channel Attack （SCA） countermeasures and is built on a security framework, such as the ISW framework, and ensures theoretical security through secret sharing. Unfortunat...Masking is one of the most commonly used Side-Channel Attack （SCA） countermeasures and is built on a security framework, such as the ISW framework, and ensures theoretical security through secret sharing. Unfortunately, the theoretical security cannot guarantee practical security, because several possible weaknesses may exist in the actual implementation. These weaknesses likely come from the masking schemes or are introduced by the implementation methods. Finding the possible weakness of the masking scheme is an interesting and important issue for real applications. In this paper, the possible weaknesses for masking schemes in Field- Programmable Gate Array （FPGA） design are discussed. It was found that the combinational circuit is the key to the security of masking schemes. The Toggle Count （TC） method and its extension are utilized to evaluate the security of masking schemes in the design phase and the implementation phase separately. Comparing different logic-level simulators for the Xilinx FPGA platform, the behavioral and post-translate simulations are considered as the analysis method in the design phase, while the post-map and the post-route simulations are used to find the weakness during the implementation phase. Moreover, a Standard Delay Format （SDF） based improvement scheme is proposed to significantly increase the effectiveness of the TC model.展开更多
文摘This paper considers a model of a recursive neuron whose circuit the author finds interesting, not because of its financial possibility, but because of its surprising electrical behavior. Below, a recursive neuron is modeled with excitatory and inhibitory triggering, and simulated using Win Spice. This model is shown to be capable of controlled toggling, and so promises energy-efficient, massively parallel computing.
文摘For training the present Neural Network(NN)models,the standard technique is to utilize decaying Learning Rates(LR).While the majority of these techniques commence with a large LR,they will decay multiple times over time.Decaying has been proved to enhance generalization as well as optimization.Other parameters,such as the network’s size,the number of hidden layers,drop-outs to avoid overfitting,batch size,and so on,are solely based on heuristics.This work has proposed Adaptive Teaching Learning Based(ATLB)Heuristic to identify the optimal hyperparameters for diverse networks.Here we consider three architec-tures Recurrent Neural Networks(RNN),Long Short Term Memory(LSTM),Bidirectional Long Short Term Memory(BiLSTM)of Deep Neural Networks for classification.The evaluation of the proposed ATLB is done through the various learning rate schedulers Cyclical Learning Rate(CLR),Hyperbolic Tangent Decay(HTD),and Toggle between Hyperbolic Tangent Decay and Triangular mode with Restarts(T-HTR)techniques.Experimental results have shown the performance improvement on the 20Newsgroup,Reuters Newswire and IMDB dataset.
文摘After nearly a decade of application and investigation, a motion amplification device with viscous dampers for energy dissipation has been recognized as an effective solution to mitigate wind or seismic excitation, especially for stiff structural systems. As a result of compensation of amplified motion, it has been proved that the efficiency of viscous damper largely depends on the motion amplification device configuration, particularly for device stiflhess. In this paper, a ＂scissor-jack＂ type of motion amplification device, called a ＂toggle brace damper＂ system, is studied. It is demonstrated that the efficiency of such a device reflected by its amplification factor is not merely a function of its geometric configuration, but is highly dependent on the support elements＇ stiffness as well, similar to the mechanism of a leverage arm. Accordingly, a mathematical model in terms of complex modulus of the viscous damper with consideration of the support brace＇s stiffness is established. The results indicate that the efficiency of the motion amplification device with viscous dampers significantly depends on the stiffness of the support elements. Other parameters, such as toggle brace configuration and damping values of the viscous damper, are studied and compared. As an application example, numerical analyses are conducted to study the dynamic performance of a 39-story office tower installed with toggle brace dampers constructed on soft soil in a reclaimed area, under a combined effect of the vortex shedding of an adjacent existing 52-story building and earthquakes. The results show that viscous dampers with a motion amplification system using a properly designed toggle brace device proved to be an effective solution to alleviate the external excitations.
文摘Jaw crusher is a kind of machine widely used in mining and aggregates industry,but it still has some shortcom- ings,such as liners wear,terrible power draw etc.The lack of research on material flow strongly limits the design improvement. The size reduction of the jaw crusher relies on the moving jaw movement that is a kind of complicated swing.Based on the move- ment analysis of the moving jaw and the single particle breakage characters,the material flow is analyzed.The measure of the breakage force is carried out.Material flow analysis is partly confirmed by the experimental results and some new information is also learned from the crushing force distribution.The job on the material flow will be helpful to the jaw crusher design improve- ment.
文摘In this research, a fast methodology to calculate the exact value of the average dynamic power consumption for CMOS combinational logic circuits is developed. The delay model used is the unit-delay model where all gates have the same propagation delay. The main advantages of this method over other techniques are its accuracy, as it is deterministic and it requires less computational effort compared to exhaustive simulation approaches. The methodology uses the Logic Pictures concept for obtaining the nodes’ toggle rates. The proposed method is applied to well-known circuits and the results are compared to exhaustive simulation and Monte Carlosimulation methods.
文摘By means of total energy calculations within the framework of the local density approximation (LDA), the interactions between a silicon Si(001) surface and a scanning probe are investigated. The tip of the probe, comprising 4 Si atoms scans along the dimer lines above an asymmetric p(2 × 1) surface, at a distance where the chemical interaction between tip-surface is dominant and responsible for image resolution. At that distance, the tip causes the dimer to toggle when it scans above the lower atom of a dimer. The toggled dimers create an alternating pattern, where the immediately adjacent neighbours of a toggled dimer remain unchanged. After the tip has fully scanned across the p(2 × 1) surface, causes the dimers to arrange in a p(2 × 2) reconstruction, reproducing the images obtained in scanning probe experiments. Our modelling methodology includes simulations that reveal the energy input required to overcome the barrier to the onset of dimer toggling. The results show that the energy input to overcome this barrier is lower for the p(2 × 1) surface than that for the p(2 × 2) or c(4 × 2) surfaces.
基金the National Distinguished PhD Dissertations(200521)the National Natural Science Foundation of China(Grant No.60736208)
文摘Taking the famous genetic toggle switch as an example,we numerically investigated the effect of noise on bistability.We found that extrinsic noise resulting from stochastic fluctuations in synthesis and degradation rates and from the environmental fluctuation in gene regulatory processes can induce coherent switch,and that there is an optimal noise intensity such that the noise not only can induce this switch,but also can amplify a weak input signal.In addition,we found that the intrinsic noise introduced through the Poisson τ-leap algorithm cannot induce such a switch.
文摘Background:Reports on the efficacy of modifications to the thread design of pedicle screws are scarce.The aim of the study was to investigate initial and early fixation of pedicle screws with a plasma-sprayed titanium coating and dual pitch in the pedicle region(dual pitch titanium-coated pedicle screw[DPTCPS])in a polyetheretherketone(PEEK)rod semi-rigid fixation system.Methods:Fifty-four sheep spine specimens and 64 sheep were used to investigate initial(“0-week”controls)and early(postoperative 6 months)fixation,respectively.Sheep were divided into dual pitch pedicle screw(DPPS),standard pitch pedicle screw(SPPS),DPTCPS,and standard pitch titanium-coated pedicle screw(SPTCPS)groups.Specimens/sheep were instrumented with four screws and two rods.Biomechanical evaluations were performed,and histology at the implant-bone interface was investigated.Results:At 0-week,mean axial pull-out strength was significantly higher for the DPTCPS and SPTCPS than the SPPS(557.0±25.2 vs.459.1±19.1 N,t=3.61,P<0.05;622.6±25.2 vs.459.1±19.1 N,t=3.43,P<0.05).On toggle-testing,the DPTCPS was significantly more resistant than the SPPS and SPTCPS(343.4±16.5 vs.237.5±12.9 N,t=3.52,P<0.05;343.4±16.5 vs.289.9±12.8 N,t=3.12,P<0.05;124.7±13.5 vs.41.9±4.3 cycles,t=2.18,P<0.05;124.7±13.5 vs.79.5±11.8 cycles,t=2.76,P<0.05).On cyclic loading,maximum displacement was significantly lower for the DPTCPS than the SPPS and SPTCPS(1.8±0.13 vs.3.76±0.19 mm,t=2.29,P<0.05;1.8±0.13 vs.2.46±10.20 mm,t=2.69,P<0.05).At post-operative 6 months,mean axial pull-out strength was significantly higher for the DPTCPS and SPTCPS than the SPPS(908.4±33.6 vs.646.5±59.4 N,t=3.34,P<0.05;925.9±53.9 vs.646.5±59.4 N,t=3.37,P<0.05).On toggle-testing,the DPTCPS was significantly more resistant than the SPPS and SPTCPS(496.9±17.9 vs.370.3±16.4 N,t=2.86,P<0.05;496.9±17.9 vs.414.1±12.8 N,t=2.74,P<0.05;249.1±11.0 vs.149.9±11.1 cycles,t=2.54,P<0.05;249.1±11.0 vs.199.8±7.2 cycles,t=2.61,P<0.05).On cyclic loading,maximum displacement was significantly lower for the DPTCPS than the SPPS and SPTCPS(0.96±0.11 vs.2.39±0.14 mm,t=2.57,P<0.05;0.96±0.11 vs.1.82±0.12 mm,t=2.73,P<0.05).Resistance to toggle testing(370.3±16.4 vs.414.1±12.8 N,t=3.29,P<0.05;149.9±11.1 vs.199.8±7.2 cycles,t=2.97,P<0.05)was significantly lower and maximum displacement in cyclic loading(2.39±0.14 vs.1.82±0.12 mm;t=3.06,P<0.05)was significantly higher for the SPTCPS than the DPTCPS.Bone-to-implant contact was significantly increased for the DPTCPS compared to the SPPS(58.3%±7.0%vs.36.5%±4.4%,t=2.74,P<0.05);there was no inflammatory reaction or degradation of coated particles.Conclusion:DPTCPSs might have stronger initial and early fixation in a PEEK rod semi-rigid fixation system.
基金supported in part by the National Natural Science Foundation of China under Grant (No. 61472292)the key technology research of new-generation high-speed and high-level security chip for smart grid (No. 526816160015)in part by the Technological Innovation of Hubei Province (Major Special Project, No. 2018AAA046)
文摘Masking is one of the most commonly used Side-Channel Attack （SCA） countermeasures and is built on a security framework, such as the ISW framework, and ensures theoretical security through secret sharing. Unfortunately, the theoretical security cannot guarantee practical security, because several possible weaknesses may exist in the actual implementation. These weaknesses likely come from the masking schemes or are introduced by the implementation methods. Finding the possible weakness of the masking scheme is an interesting and important issue for real applications. In this paper, the possible weaknesses for masking schemes in Field- Programmable Gate Array （FPGA） design are discussed. It was found that the combinational circuit is the key to the security of masking schemes. The Toggle Count （TC） method and its extension are utilized to evaluate the security of masking schemes in the design phase and the implementation phase separately. Comparing different logic-level simulators for the Xilinx FPGA platform, the behavioral and post-translate simulations are considered as the analysis method in the design phase, while the post-map and the post-route simulations are used to find the weakness during the implementation phase. Moreover, a Standard Delay Format （SDF） based improvement scheme is proposed to significantly increase the effectiveness of the TC model.
