“Alone together”is an ever-changing“wicked problem.”In this research and practice,the author tries to combine experience design,referring to the theory of“interaction ritual chain theory,”and creatively add inte...“Alone together”is an ever-changing“wicked problem.”In this research and practice,the author tries to combine experience design,referring to the theory of“interaction ritual chain theory,”and creatively add interactive experience to discursive works,so that the audience can think between the real and the virtual.展开更多
Hadoop is a well-known parallel computing system for distributed computing and large-scale data processes.“Straggling”tasks,however,have a serious impact on task allocation and scheduling in a Hadoop system.Speculat...Hadoop is a well-known parallel computing system for distributed computing and large-scale data processes.“Straggling”tasks,however,have a serious impact on task allocation and scheduling in a Hadoop system.Speculative Execution(SE)is an efficient method of processing“Straggling”Tasks by monitoring real-time running status of tasks and then selectively backing up“Stragglers”in another node to increase the chance to complete the entire mission early.Present speculative execution strategies meet challenges on misjudgement of“Straggling”tasks and improper selection of backup nodes,which leads to inefficient implementation of speculative executive processes.This paper has proposed an Optimized Resource Scheduling strategy for Speculative Execution(ORSE)by introducing non-cooperative game schemes.The ORSE transforms the resource scheduling of backup tasks into a multi-party non-cooperative game problem,where the tasks are regarded as game participants,whilst total task execution time of the entire cluster as the utility function.In that case,the most benefit strategy can be implemented in each computing node when the game reaches a Nash equilibrium point,i.e.,the final resource scheduling scheme to be obtained.The strategy has been implemented in Hadoop-2.x.Experimental results depict that the ORSE can maintain the efficiency of speculative executive processes and improve fault-tolerant and computation performance under the circumstances of Normal Load,Busy Load and Busy Load with Skewed Data.展开更多
As a distributed computing platform, Hadoop provides an effective way to handle big data. In Hadoop, the completion time of job will be delayed by a straggler. Although the definitive cause of the straggler is hard to...As a distributed computing platform, Hadoop provides an effective way to handle big data. In Hadoop, the completion time of job will be delayed by a straggler. Although the definitive cause of the straggler is hard to detect, speculative execution is usually used for dealing with this problem, by simply backing up those stragglers on alternative nodes. In this paper, we design a new Speculative Execution algorithm based on C4.5 Decision Tree, SECDT, for Hadoop. In SECDT, we speculate completion time of stragglers and also of backup tasks, based on a kind of decision tree method: C4.5 decision tree. After we speculate the completion time, we compare the completion time of stragglers and of the backup tasks, calculating their differential value, and selecting the straggler with the maximum differential value to start the backup task.Experiment result shows that the SECDT can predict execution time more accurately than other speculative execution methods, hence reduce the job completion time.展开更多
There are two inaccuracies to the common belief that hot money flows into China through international trade: "hot money" and "trade channels". First, China’s domestic financial market is still at ...There are two inaccuracies to the common belief that hot money flows into China through international trade: "hot money" and "trade channels". First, China’s domestic financial market is still at the initial stage of development, and foreign exchange control has put barriers to entry and exit of overseas capital. Strictly speaking, the short-term highly liquid "hot money" does not exist in China, and is referred to as long-term speculative capital in this paper. Second, such capital does not come from trade alone. International trade is only part of corporate business operations, and a more reasonable and complete description is that "overseas capital flows into China through foreign-funded enterprises". Through analysis of the inflow channels, this paper estimates that the stock of long-term speculative capital between 1999 and 2006 stands at almost US$ 400 billion. The year 2006 saw an increase of US$ 98.09 billion, of which US$ 35.4 billion was formed through international trade, which equals to roughly 20% of trade surplus that year. But this does not mean that 20% of trade surplus is long-term speculative capital.展开更多
Speculative execution attacks can leak arbitrary program data under malicious speculation,presenting a severe security threat.Based on two key observations,this paper presents a software-transparent defense mechanism ...Speculative execution attacks can leak arbitrary program data under malicious speculation,presenting a severe security threat.Based on two key observations,this paper presents a software-transparent defense mechanism called speculative secret flow tracking(SSFT),which is capable of defending against all cache-based speculative execution attacks with a low performance overhead.First,we observe that the attacker must use array or pointer variables in the victim code to access arbitrary memory data.Therefore,we propose a strict definition of secret data to reduce the amount of data to be protected.Second,if the load is not data-dependent and control-dependent on secrets,its speculative execution will not leak any secrets.Thus,this paper introduces the concept of speculative secret flow to analyze how secret data are obtained and propagated during speculative execution.By tracking speculative secret flow in hardware,SSFT can identify all unsafe speculative loads(USLs)that are dependent on secrets.Moreover,SSFT exploits three different methods to constrain USLs’speculative execution and prevent them from leaking secrets into the cache and translation lookaside buffer(TLB)states.This paper evaluates the performance of SSFT on the SPEC CPU 2006 workloads,and the results show that SSFT is effective and its performance overhead is very low.To defend against all speculative execution attack variants,SSFT only incurs an average slowdown of 4.5%(Delay USL-L1Miss)or 3.8%(Invisible USLs)compared to a non-secure processor.Our analysis also shows that SSFT maintains a low hardware overhead.展开更多
By applying two nonlinear Granger causality testing methods and rolling window strategy to explore the relationship between speculative activities and crude oil prices, the unidirectional Granger causality from specul...By applying two nonlinear Granger causality testing methods and rolling window strategy to explore the relationship between speculative activities and crude oil prices, the unidirectional Granger causality from speculative activities to returns of crude oil prices during the high price phase is discovered. It is proved that speculative activities did contribute to high crude oil prices after the Asian financial crisis and OPEC＇s output cut in 1998. The unidirectional Granger causality from returns of crude oil prices to speculative activities is significant in general. But after 2000, with the sharp rise in crude oil prices, this unidirectional Granger causality became a complex nonlinear relationship, which cannot be detected by any linear Granger causaIity test.展开更多
Thread partition plays an important role in speculative multithreading （SpMT） for automatic parallelization of ir- regular programs. Using unified values of partition parameters to partition different applications l...Thread partition plays an important role in speculative multithreading （SpMT） for automatic parallelization of ir- regular programs. Using unified values of partition parameters to partition different applications leads to the fact that every ap- plication cannot own its optimal partition scheme. In this paper, five parameters affecting thread partition are extracted from heuristic rules. They are the dependence threshold （DT）, lower limit of thread size （TSL）, upper limit of thread size （TSU）, lower limit of spawning distance （SDL）, and upper limit of spawning distance （SDU）. Their ranges are determined in accordance with heuristic rules, and their step-sizes are set empirically. Under the condition of setting speedup as an objective function, all com- binations of five threshold values form the solution space, and our aim is to search for the best combination to obtain the best thread granularity, thread dependence, and spawning distance, so that every application has its best partition scheme. The issue can be attributed to a single objective optimization problem. We use the artificial immune algorithm （AIA） to search for the optimal solution. On Prophet, which is a generic SpMT processor to evaluate the performance of multithreaded programs, Olden bench- marks are used to implement the process. Experiments show that we can obtain the optimal parameter values for every benchmark, and Olden benchmarks partitioned with the optimized parameter values deliver a performance improvement of 3.00% on a 4-core platform compared with a machine learning based approach, and 8.92% compared with a heuristics-based approach.展开更多
With the development and widespread use of blockchain in recent years,many projects have introduced blockchain technology to solve the growing security issues of the Industrial Internet of Things(IIoT).However,due to ...With the development and widespread use of blockchain in recent years,many projects have introduced blockchain technology to solve the growing security issues of the Industrial Internet of Things(IIoT).However,due to the conflict between the operational performance and security of the blockchain system and the compatibility issues with a large number of IIoT devices running together,the mainstream blockchain system cannot be applied to IIoT scenarios.In order to solve these problems,this paper proposes SBFT(Speculative Byzantine Consensus Protocol),a flexible and scalable blockchain consensus mechanism for the Industrial Internet of Things.SBFT has a consensus process based on speculation,improving the throughput and consensus speed of blockchain systems and reducing communication overhead.In order to improve the compatibility and scalability of the blockchain system,we select some nodes to participate in the consensus,and these nodes have better performance in the network.Since multiple properties determine node performance,we abstract the node selection problem as a joint optimization problem and use Dueling Deep Q Learning(DQL)to solve it.Finally,we evaluate the performance of the scheme through simulation,and the simulation results prove the superiority of our scheme.展开更多
Read-write dependency is an important factor restricting software efficiency.Timing Speculative(TS)is a processing architecture aiming to improve energy efficiency of microprocessors.Timing error rate,influenced by th...Read-write dependency is an important factor restricting software efficiency.Timing Speculative(TS)is a processing architecture aiming to improve energy efficiency of microprocessors.Timing error rate,influenced by the read-write dependency,bottlenecks the voltage down-scaling and so the energy efficiency of TS processors.We proposed a method called Read-Write Dependency Aware Register Allocation.It is based on the Read-Write Dependency aware Interference Graph(RWDIG)conception.Registers are reallocated to loosen the read-write dependencies,so resulting in a reduction of timing errors.The traditional no operation(Nop)padding method is also redesigned to increase the distance value to above 2.We analyzed the dependencies of registers and maximized the average distance value of read and write dependencies.Experimental results showed that we can reduce all read-write dependency by Nop padding,as well as the overhead timing errors.An energy saving of approximately 7%was achieved.展开更多
By using GARCH（1,1）-M and EGARCH（1,1）-M models, the relationships among funds speculation transaction, arbitrage transaction and the fluctuation of international copper future price were studied. The news impact c...By using GARCH（1,1）-M and EGARCH（1,1）-M models, the relationships among funds speculation transaction, arbitrage transaction and the fluctuation of international copper future price were studied. The news impact curve of copper future price fluctuation respectively introduced funds speculation position and arbitrage position was given, and the result is consistent with the empirical study conclusion. The results show that investment funds are not the factor that causes copper future price fluctuation, but can reduce the copper future price fluctuation; the copper future price fluctuation is more sensitive to negative information, and ftmd speculative positions can reduce asymmetric effect of copper price fluctuation, while fimds arbitrage position influences less.展开更多
Timing speculative(TS)architecture is promising for improving the energy efficiency of microprocessors.Error recovery units,designed for tolerating occasional timing errors,have been used to support a wider range of v...Timing speculative(TS)architecture is promising for improving the energy efficiency of microprocessors.Error recovery units,designed for tolerating occasional timing errors,have been used to support a wider range of voltage scaling,therefore to achieve a better energy efficiency.More specifically,the timing error rate,influenced mainly by data forwarding,is the bottleneck for voltage down-scaling in TS processors.In this paper,a new Timing Error Aware Register Allocation method is proposed.First,we designed the Dependency aware Interference Graph(DIG)construction to get the information of Read after Write(RAW)in programs.To build the construction,we get the disassemble code as input and suppose that there are unlimited registers,the same way as so-called virtual registers in many compilers.Then we change the disassemble codes to the SSA form for each basic block to make sure the registers are defined only once.Based on the DIG construction,registers were real-located to eliminate the timing error,by loosening the RAW dependencies.We con-struct the DIG for each function of the program and sort the edge of DIG by an increasing weight order.Since a smaller weighted-edge value means that its owner nodes have more frequent access in instruction flows,we expect it in different registers with no read-write dependency.At the same time,we make sure that there are no additional new spill codes emerging in our algorithm to minimize the rate of spill code.A high rate of spill code will not only decrease the performance of the system but also increase the unexpected read-write dependency.Next,we reallocate the reg-isters by weight order in turn to loosen the RAW dependencies.Furthermore,we use the NOP operation to pad the instructions with a minimal distance value of 2.Experiment results showed that the average distance of RAW dependencies was increased by over 20%.展开更多
Speculative-fiction stories, in print, often depict families being wrenched apart by overwhelming new forces to which the children are better able to adapt then older generations. In making speculative-fiction movies,...Speculative-fiction stories, in print, often depict families being wrenched apart by overwhelming new forces to which the children are better able to adapt then older generations. In making speculative-fiction movies, however, Hollywood typically offers a more hopeful, comforting image of a family, at the beginning somewhat less than perfect, being restored as a result of those same forces. This paper concentrates on The Spiderwick Chronicles （2003-2004） by Tony DiTerlizzi and Holly Black, Susan Cooper＇s novel The Dark is Rising （1973）, and Lewis Padgett＇s story ＂Mimsy were the Borogoves＂ and the recent movies based （more or less loosely） thereon, Mark Waters＇ The Spiderwick Chronicles （2007）, David Cunningham＇s The Seeker （2007）, and Bob Shaye＇s The Last Mimzy （2007）, showing how the differences between the movies and the print-stories they are based on reflect an attempt on the part of the movie-makers to reaffirm and reinforce the family bonds that are to some extent sundered in the original stories展开更多
Empirical, formal, and speculative understandings of logic as identified by Hegel will be formalized. Being formalized the propositions will be deduced from how probabilities can be used to make decisions by appropria...Empirical, formal, and speculative understandings of logic as identified by Hegel will be formalized. Being formalized the propositions will be deduced from how probabilities can be used to make decisions by appropriating Hegel＇s concept of being two-sided for inferences. This will work for what I will call grounded as opposed to ungrounded probability functions. The domain of their values will be decided by a three-valued modal relation of the binomial probability function. Keynes （1920, Ch. IV ~17） and Popper＇s （1959, Ch. 59） solution to the problem of unknown proportions will be challenged by an understanding of logic that puts the content of what the axioms mean for making rational decisions before their mere being. What is true for the different types inferences will then work for the principle of the dialectic in contrast to the two proposed by Hume and the one proposed by David Lewis. In this way, it will be demonstrated that Hegel＇s understanding of logic is still more advanced than one that fails to recognize it falls within the scope of the dialectic. Dialectic as such will be a principle where the different understandings of a predicated logic will have a modal value within a higher standpoint of system.展开更多
Architectural design course is the main course of architecture major.“Master-apprentice” guidance is the main mode of architectural design course teaching.How to teach between teachers and apprentices? Architectural...Architectural design course is the main course of architecture major.“Master-apprentice” guidance is the main mode of architectural design course teaching.How to teach between teachers and apprentices? Architectural design teachers in different colleges and universities do not have a unified approach,which easily leads to confusion in teaching.This study put forward “ 3W ” teaching method,and made a preliminary discussion on its concept,structure and application.“ 3W ” method is a method that the architectural design instructor uses three progressive questions to guide the whole process of architectural design.Through a detailed discussion of the three questions,it showed that this method was a building design guiding method with simple operation,easy grasp and adaptability.展开更多
Based on the commodity property and finance property of gold in the international gold futures market,the influence factors of international gold futures price volatility are analyzed from the perspectives of supply a...Based on the commodity property and finance property of gold in the international gold futures market,the influence factors of international gold futures price volatility are analyzed from the perspectives of supply and demand factors,financial factors and speculation factors.The structural vector autoregression(SVAR)model is applied to investigating the direction and strength of the effects of influence factors on the international gold futures prices and the variance decomposition approach(VDA)is used to compare the contributions of these factors.The results show that the supply and demand factors still play a fundamental role in the international gold futures price volatility and the role of“China’s gold demand”is exaggerated.The financial factors and speculation factors have significant impacts on the international gold futures price volatility,which reflects that the financial property of gold becomes increasingly important.Governments and investors should pay close attention to the financial property of gold futures.展开更多
Over the past decade, agricultural commodity prices underwent wild swings, Periods of high growth in 2008 were followed by periods of sudden decrease in 2009, The excessive increase in food price volatility is a subje...Over the past decade, agricultural commodity prices underwent wild swings, Periods of high growth in 2008 were followed by periods of sudden decrease in 2009, The excessive increase in food price volatility is a subject of great interest because it has to do with the survival of mankind, Recent academic studies and policy makers have reached sharply different conclusions about the dynamics of such fluctuations, Also, some of them have indicated the main cause in speculative transactions and in the little regulation of futures markets, This paper intends to verify if there exists a co-implication between wheat futures price and some financial “speculative” variables, The results of cointegration analysis show that there is no evidence that financial derivative instruments determine the fluctuations of wheat futures price.展开更多
This paper presents a novel automatic mammography recognition approach used to develop computer-aided diagnostic systems that require a robust method to assist the radiologist in identifying and recognizing speculatio...This paper presents a novel automatic mammography recognition approach used to develop computer-aided diagnostic systems that require a robust method to assist the radiologist in identifying and recognizing speculations from a multitude of lines corresponding to the normal fibrous breast tissue.Following this rationale,this paper introduces a novel approach for detecting the speculated lesions in digital mammograms based on multi-scale SIFT(scale-invariant feature transform)orientations.The proposed method starts by estimating a set of key points that best represent the image mammography in a scale space.We then benefit from SIFT algorithm to locally characterize each key point by assigning a consistent orientation.Thereafter,a set of three features are extracted for each pixel in the image mammogram based on these orientations.The extracted features are fed into BDT(binary decision tree)in order to perform per pixel classification and decide whether the pixel is normal or abnormal.We evaluate the proposed system on BCDR(breast cancer digital repository)database and the experimental results show that our method is accurate with 97.95%recognition rate,while it is robust to illumination changes,rotation and scale variations.展开更多
Sneaker speculation is one of the most attractive economic phenomena.The purpose of the paper is to avoid too many consumers blindly following the trend to join the sneaker speculation and eventually causes financial ...Sneaker speculation is one of the most attractive economic phenomena.The purpose of the paper is to avoid too many consumers blindly following the trend to join the sneaker speculation and eventually causes financial lost due to the sneaker speculation trend being too hot.This study is one of the first few attempts to analyze every aspect of sneaker speculation and give youth suggestion on purchasing sneakers.First,this paper analyzed the cause and influential aspect of sneaker speculation,and made a preliminary analysis for readers who first enter the sneaker market.Second,the risk of sneaker speculation was analyzed.Then,suggestions for the youth to establish correct values and consumption concept were given.Finally,the conclusion suggested that the price of sneakers is too high over their value,consumers should buy sneaker rationally.Hopefully,consumers can establish a more rational consumption concept for consumers.More powerfully regulated sneaker market is necessary,so that the price of sneakers is more reasonable and affordable for consumers.展开更多
文摘“Alone together”is an ever-changing“wicked problem.”In this research and practice,the author tries to combine experience design,referring to the theory of“interaction ritual chain theory,”and creatively add interactive experience to discursive works,so that the audience can think between the real and the virtual.
基金This work has received funding from the European Unions Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no.701697Major Program of the National Social Science Fund of China(Grant No.17ZDA092)+2 种基金Basic Research Programs(Natural Science Foundation)of Jiangsu Province(BK20180794)333 High-Level Talent Cultivation Project of Jiangsu Province(BRA2018332)333 High-Level Talent Cultivation Project of Jiangsu Province(BRA2018332)the PAPD fund.
文摘Hadoop is a well-known parallel computing system for distributed computing and large-scale data processes.“Straggling”tasks,however,have a serious impact on task allocation and scheduling in a Hadoop system.Speculative Execution(SE)is an efficient method of processing“Straggling”Tasks by monitoring real-time running status of tasks and then selectively backing up“Stragglers”in another node to increase the chance to complete the entire mission early.Present speculative execution strategies meet challenges on misjudgement of“Straggling”tasks and improper selection of backup nodes,which leads to inefficient implementation of speculative executive processes.This paper has proposed an Optimized Resource Scheduling strategy for Speculative Execution(ORSE)by introducing non-cooperative game schemes.The ORSE transforms the resource scheduling of backup tasks into a multi-party non-cooperative game problem,where the tasks are regarded as game participants,whilst total task execution time of the entire cluster as the utility function.In that case,the most benefit strategy can be implemented in each computing node when the game reaches a Nash equilibrium point,i.e.,the final resource scheduling scheme to be obtained.The strategy has been implemented in Hadoop-2.x.Experimental results depict that the ORSE can maintain the efficiency of speculative executive processes and improve fault-tolerant and computation performance under the circumstances of Normal Load,Busy Load and Busy Load with Skewed Data.
文摘As a distributed computing platform, Hadoop provides an effective way to handle big data. In Hadoop, the completion time of job will be delayed by a straggler. Although the definitive cause of the straggler is hard to detect, speculative execution is usually used for dealing with this problem, by simply backing up those stragglers on alternative nodes. In this paper, we design a new Speculative Execution algorithm based on C4.5 Decision Tree, SECDT, for Hadoop. In SECDT, we speculate completion time of stragglers and also of backup tasks, based on a kind of decision tree method: C4.5 decision tree. After we speculate the completion time, we compare the completion time of stragglers and of the backup tasks, calculating their differential value, and selecting the straggler with the maximum differential value to start the backup task.Experiment result shows that the SECDT can predict execution time more accurately than other speculative execution methods, hence reduce the job completion time.
文摘There are two inaccuracies to the common belief that hot money flows into China through international trade: "hot money" and "trade channels". First, China’s domestic financial market is still at the initial stage of development, and foreign exchange control has put barriers to entry and exit of overseas capital. Strictly speaking, the short-term highly liquid "hot money" does not exist in China, and is referred to as long-term speculative capital in this paper. Second, such capital does not come from trade alone. International trade is only part of corporate business operations, and a more reasonable and complete description is that "overseas capital flows into China through foreign-funded enterprises". Through analysis of the inflow channels, this paper estimates that the stock of long-term speculative capital between 1999 and 2006 stands at almost US$ 400 billion. The year 2006 saw an increase of US$ 98.09 billion, of which US$ 35.4 billion was formed through international trade, which equals to roughly 20% of trade surplus that year. But this does not mean that 20% of trade surplus is long-term speculative capital.
基金supported by the Key-Area Research and Development Program of Guangdong Province of China under Grant No.2018B010115002.
文摘Speculative execution attacks can leak arbitrary program data under malicious speculation,presenting a severe security threat.Based on two key observations,this paper presents a software-transparent defense mechanism called speculative secret flow tracking(SSFT),which is capable of defending against all cache-based speculative execution attacks with a low performance overhead.First,we observe that the attacker must use array or pointer variables in the victim code to access arbitrary memory data.Therefore,we propose a strict definition of secret data to reduce the amount of data to be protected.Second,if the load is not data-dependent and control-dependent on secrets,its speculative execution will not leak any secrets.Thus,this paper introduces the concept of speculative secret flow to analyze how secret data are obtained and propagated during speculative execution.By tracking speculative secret flow in hardware,SSFT can identify all unsafe speculative loads(USLs)that are dependent on secrets.Moreover,SSFT exploits three different methods to constrain USLs’speculative execution and prevent them from leaking secrets into the cache and translation lookaside buffer(TLB)states.This paper evaluates the performance of SSFT on the SPEC CPU 2006 workloads,and the results show that SSFT is effective and its performance overhead is very low.To defend against all speculative execution attack variants,SSFT only incurs an average slowdown of 4.5%(Delay USL-L1Miss)or 3.8%(Invisible USLs)compared to a non-secure processor.Our analysis also shows that SSFT maintains a low hardware overhead.
基金supported by the National Natural Science Foundation of China
文摘By applying two nonlinear Granger causality testing methods and rolling window strategy to explore the relationship between speculative activities and crude oil prices, the unidirectional Granger causality from speculative activities to returns of crude oil prices during the high price phase is discovered. It is proved that speculative activities did contribute to high crude oil prices after the Asian financial crisis and OPEC＇s output cut in 1998. The unidirectional Granger causality from returns of crude oil prices to speculative activities is significant in general. But after 2000, with the sharp rise in crude oil prices, this unidirectional Granger causality became a complex nonlinear relationship, which cannot be detected by any linear Granger causaIity test.
基金supported by the National Natural Science Foundation of China(No.61173040)the Doctoral Fund of Ministry of Education of China(No.2013021110012)
文摘Thread partition plays an important role in speculative multithreading （SpMT） for automatic parallelization of ir- regular programs. Using unified values of partition parameters to partition different applications leads to the fact that every ap- plication cannot own its optimal partition scheme. In this paper, five parameters affecting thread partition are extracted from heuristic rules. They are the dependence threshold （DT）, lower limit of thread size （TSL）, upper limit of thread size （TSU）, lower limit of spawning distance （SDL）, and upper limit of spawning distance （SDU）. Their ranges are determined in accordance with heuristic rules, and their step-sizes are set empirically. Under the condition of setting speedup as an objective function, all com- binations of five threshold values form the solution space, and our aim is to search for the best combination to obtain the best thread granularity, thread dependence, and spawning distance, so that every application has its best partition scheme. The issue can be attributed to a single objective optimization problem. We use the artificial immune algorithm （AIA） to search for the optimal solution. On Prophet, which is a generic SpMT processor to evaluate the performance of multithreaded programs, Olden bench- marks are used to implement the process. Experiments show that we can obtain the optimal parameter values for every benchmark, and Olden benchmarks partitioned with the optimized parameter values deliver a performance improvement of 3.00% on a 4-core platform compared with a machine learning based approach, and 8.92% compared with a heuristics-based approach.
文摘With the development and widespread use of blockchain in recent years,many projects have introduced blockchain technology to solve the growing security issues of the Industrial Internet of Things(IIoT).However,due to the conflict between the operational performance and security of the blockchain system and the compatibility issues with a large number of IIoT devices running together,the mainstream blockchain system cannot be applied to IIoT scenarios.In order to solve these problems,this paper proposes SBFT(Speculative Byzantine Consensus Protocol),a flexible and scalable blockchain consensus mechanism for the Industrial Internet of Things.SBFT has a consensus process based on speculation,improving the throughput and consensus speed of blockchain systems and reducing communication overhead.In order to improve the compatibility and scalability of the blockchain system,we select some nodes to participate in the consensus,and these nodes have better performance in the network.Since multiple properties determine node performance,we abstract the node selection problem as a joint optimization problem and use Dueling Deep Q Learning(DQL)to solve it.Finally,we evaluate the performance of the scheme through simulation,and the simulation results prove the superiority of our scheme.
基金This work was supported by the Project of Hunan Social Science Achievement Evaluation Committee(XSP20YBZ090,Sheng Xiao,2020).
文摘Read-write dependency is an important factor restricting software efficiency.Timing Speculative(TS)is a processing architecture aiming to improve energy efficiency of microprocessors.Timing error rate,influenced by the read-write dependency,bottlenecks the voltage down-scaling and so the energy efficiency of TS processors.We proposed a method called Read-Write Dependency Aware Register Allocation.It is based on the Read-Write Dependency aware Interference Graph(RWDIG)conception.Registers are reallocated to loosen the read-write dependencies,so resulting in a reduction of timing errors.The traditional no operation(Nop)padding method is also redesigned to increase the distance value to above 2.We analyzed the dependencies of registers and maximized the average distance value of read and write dependencies.Experimental results showed that we can reduce all read-write dependency by Nop padding,as well as the overhead timing errors.An energy saving of approximately 7%was achieved.
基金Project(20090162120086) supported by Research Fund for the Doctoral Program of Higher Education of ChinaProject(10YJCZH123) supported by Humanity and Social Science Foundation of Ministry of Education of China+2 种基金Project(12JJ4077) supported by the National Natural Science Foundation of Hunan Province of ChinaProject(2009ZK3053) supported by Soft Science Research Project of Hunan Province of ChinaProject supported by the Freedom Explore Program of Central South University,China
文摘By using GARCH（1,1）-M and EGARCH（1,1）-M models, the relationships among funds speculation transaction, arbitrage transaction and the fluctuation of international copper future price were studied. The news impact curve of copper future price fluctuation respectively introduced funds speculation position and arbitrage position was given, and the result is consistent with the empirical study conclusion. The results show that investment funds are not the factor that causes copper future price fluctuation, but can reduce the copper future price fluctuation; the copper future price fluctuation is more sensitive to negative information, and ftmd speculative positions can reduce asymmetric effect of copper price fluctuation, while fimds arbitrage position influences less.
基金This work was supported by the General Project of Humanities and Social Sciences Research of the Ministry of Education(16YJA740039,Sheng Xiao,2016)the Foundation Project of Philosophy and Social Science of Hunan(17YBA115,Sheng Xiao,2018).
文摘Timing speculative(TS)architecture is promising for improving the energy efficiency of microprocessors.Error recovery units,designed for tolerating occasional timing errors,have been used to support a wider range of voltage scaling,therefore to achieve a better energy efficiency.More specifically,the timing error rate,influenced mainly by data forwarding,is the bottleneck for voltage down-scaling in TS processors.In this paper,a new Timing Error Aware Register Allocation method is proposed.First,we designed the Dependency aware Interference Graph(DIG)construction to get the information of Read after Write(RAW)in programs.To build the construction,we get the disassemble code as input and suppose that there are unlimited registers,the same way as so-called virtual registers in many compilers.Then we change the disassemble codes to the SSA form for each basic block to make sure the registers are defined only once.Based on the DIG construction,registers were real-located to eliminate the timing error,by loosening the RAW dependencies.We con-struct the DIG for each function of the program and sort the edge of DIG by an increasing weight order.Since a smaller weighted-edge value means that its owner nodes have more frequent access in instruction flows,we expect it in different registers with no read-write dependency.At the same time,we make sure that there are no additional new spill codes emerging in our algorithm to minimize the rate of spill code.A high rate of spill code will not only decrease the performance of the system but also increase the unexpected read-write dependency.Next,we reallocate the reg-isters by weight order in turn to loosen the RAW dependencies.Furthermore,we use the NOP operation to pad the instructions with a minimal distance value of 2.Experiment results showed that the average distance of RAW dependencies was increased by over 20%.
文摘Speculative-fiction stories, in print, often depict families being wrenched apart by overwhelming new forces to which the children are better able to adapt then older generations. In making speculative-fiction movies, however, Hollywood typically offers a more hopeful, comforting image of a family, at the beginning somewhat less than perfect, being restored as a result of those same forces. This paper concentrates on The Spiderwick Chronicles （2003-2004） by Tony DiTerlizzi and Holly Black, Susan Cooper＇s novel The Dark is Rising （1973）, and Lewis Padgett＇s story ＂Mimsy were the Borogoves＂ and the recent movies based （more or less loosely） thereon, Mark Waters＇ The Spiderwick Chronicles （2007）, David Cunningham＇s The Seeker （2007）, and Bob Shaye＇s The Last Mimzy （2007）, showing how the differences between the movies and the print-stories they are based on reflect an attempt on the part of the movie-makers to reaffirm and reinforce the family bonds that are to some extent sundered in the original stories
文摘Empirical, formal, and speculative understandings of logic as identified by Hegel will be formalized. Being formalized the propositions will be deduced from how probabilities can be used to make decisions by appropriating Hegel＇s concept of being two-sided for inferences. This will work for what I will call grounded as opposed to ungrounded probability functions. The domain of their values will be decided by a three-valued modal relation of the binomial probability function. Keynes （1920, Ch. IV ~17） and Popper＇s （1959, Ch. 59） solution to the problem of unknown proportions will be challenged by an understanding of logic that puts the content of what the axioms mean for making rational decisions before their mere being. What is true for the different types inferences will then work for the principle of the dialectic in contrast to the two proposed by Hume and the one proposed by David Lewis. In this way, it will be demonstrated that Hegel＇s understanding of logic is still more advanced than one that fails to recognize it falls within the scope of the dialectic. Dialectic as such will be a principle where the different understandings of a predicated logic will have a modal value within a higher standpoint of system.
基金Sponsored by Education Reform Project of Jiangxi Province in 2014(JXJG-14-2-23)
文摘Architectural design course is the main course of architecture major.“Master-apprentice” guidance is the main mode of architectural design course teaching.How to teach between teachers and apprentices? Architectural design teachers in different colleges and universities do not have a unified approach,which easily leads to confusion in teaching.This study put forward “ 3W ” teaching method,and made a preliminary discussion on its concept,structure and application.“ 3W ” method is a method that the architectural design instructor uses three progressive questions to guide the whole process of architectural design.Through a detailed discussion of the three questions,it showed that this method was a building design guiding method with simple operation,easy grasp and adaptability.
基金Projects(71874210,71633006,71501193) supported by the National Natural Science Foundation of China
文摘Based on the commodity property and finance property of gold in the international gold futures market,the influence factors of international gold futures price volatility are analyzed from the perspectives of supply and demand factors,financial factors and speculation factors.The structural vector autoregression(SVAR)model is applied to investigating the direction and strength of the effects of influence factors on the international gold futures prices and the variance decomposition approach(VDA)is used to compare the contributions of these factors.The results show that the supply and demand factors still play a fundamental role in the international gold futures price volatility and the role of“China’s gold demand”is exaggerated.The financial factors and speculation factors have significant impacts on the international gold futures price volatility,which reflects that the financial property of gold becomes increasingly important.Governments and investors should pay close attention to the financial property of gold futures.
文摘Over the past decade, agricultural commodity prices underwent wild swings, Periods of high growth in 2008 were followed by periods of sudden decrease in 2009, The excessive increase in food price volatility is a subject of great interest because it has to do with the survival of mankind, Recent academic studies and policy makers have reached sharply different conclusions about the dynamics of such fluctuations, Also, some of them have indicated the main cause in speculative transactions and in the little regulation of futures markets, This paper intends to verify if there exists a co-implication between wheat futures price and some financial “speculative” variables, The results of cointegration analysis show that there is no evidence that financial derivative instruments determine the fluctuations of wheat futures price.
文摘This paper presents a novel automatic mammography recognition approach used to develop computer-aided diagnostic systems that require a robust method to assist the radiologist in identifying and recognizing speculations from a multitude of lines corresponding to the normal fibrous breast tissue.Following this rationale,this paper introduces a novel approach for detecting the speculated lesions in digital mammograms based on multi-scale SIFT(scale-invariant feature transform)orientations.The proposed method starts by estimating a set of key points that best represent the image mammography in a scale space.We then benefit from SIFT algorithm to locally characterize each key point by assigning a consistent orientation.Thereafter,a set of three features are extracted for each pixel in the image mammogram based on these orientations.The extracted features are fed into BDT(binary decision tree)in order to perform per pixel classification and decide whether the pixel is normal or abnormal.We evaluate the proposed system on BCDR(breast cancer digital repository)database and the experimental results show that our method is accurate with 97.95%recognition rate,while it is robust to illumination changes,rotation and scale variations.
文摘Sneaker speculation is one of the most attractive economic phenomena.The purpose of the paper is to avoid too many consumers blindly following the trend to join the sneaker speculation and eventually causes financial lost due to the sneaker speculation trend being too hot.This study is one of the first few attempts to analyze every aspect of sneaker speculation and give youth suggestion on purchasing sneakers.First,this paper analyzed the cause and influential aspect of sneaker speculation,and made a preliminary analysis for readers who first enter the sneaker market.Second,the risk of sneaker speculation was analyzed.Then,suggestions for the youth to establish correct values and consumption concept were given.Finally,the conclusion suggested that the price of sneakers is too high over their value,consumers should buy sneaker rationally.Hopefully,consumers can establish a more rational consumption concept for consumers.More powerfully regulated sneaker market is necessary,so that the price of sneakers is more reasonable and affordable for consumers.
