开发Java Web项目中发现服务之间的调用存在超时情况,由于涉及的处理逻辑全部是异步,引入定时重试的机制,重试工具选择了JDK自带的Scheduled Thread Pool Executor。当A服务依赖B服务,B服务由于在业务高峰期处理能力降低,导致大量A服务...开发Java Web项目中发现服务之间的调用存在超时情况,由于涉及的处理逻辑全部是异步,引入定时重试的机制,重试工具选择了JDK自带的Scheduled Thread Pool Executor。当A服务依赖B服务,B服务由于在业务高峰期处理能力降低,导致大量A服务过来的请求超时,A加入了超时重试机制,间隔时间根据重试次数的多少来决定,次数越多,两次重试之间间隔的时间越多,此时的业务高峰也会给A带来大量请求,大量的超时会导致重试队列迅速堆积,直到内存溢出。该文从线程池工作机制、Scheduled Thread Pool Executor实例的创建,获取重试任务的过程以及提交任务的过程角度分析,并通过源代码的剖析和测试工具My Eclipse进行演示测试内存泄露的情况,得出避免内存泄露的解决方案。展开更多
Firstly analyzes the CHAOS and points out its shortages, and then uses the basic method—inspector/executor to deal with irregular computation, and offers the realization scheme for the CHAOS+ runtime library that sup...Firstly analyzes the CHAOS and points out its shortages, and then uses the basic method—inspector/executor to deal with irregular computation, and offers the realization scheme for the CHAOS+ runtime library that supports irregular computation, and finally gives the node code program to show the example with CHAOS+ runtime library.展开更多
After analyzing the reasons for coal mine accidents and the current management methods, effective actions for the implementation of safety management were put forward by carrying out the whole process confirmation man...After analyzing the reasons for coal mine accidents and the current management methods, effective actions for the implementation of safety management were put forward by carrying out the whole process confirmation management. The ba- sic content and the five implementation steps were described, and the implementation method and the program of every step were introduced. Some rules for the implementation of the whole process confirmation management in coal mine safety pro- duction were explained, such as during the process of preproduction, before descent, descent, after descent, walking in the roadway, post-operation, shift, and hoisting after work. The results show that the guardians and the executors should both con- firm the implementation, which can improve the workers＇ attention and self-awareness to avoid errors in detail and reduce the ＂three violations＂ phenomenon. To ensure the effect of the whole process confirmation management, relevant departments should designate a person-in-charge in the specific work in all stages, make a work plan, and strengthen the internal evaluation.展开更多
Scalability is one of the most important quality attribute of softwareintensive systems,because it maintains an effective performance parallel to the large fluctuating and sometimes unpredictable workload.In order to ...Scalability is one of the most important quality attribute of softwareintensive systems,because it maintains an effective performance parallel to the large fluctuating and sometimes unpredictable workload.In order to achieve scalability,thread pool system(TPS)(which is also known as executor service)has been used extensively as a middleware service in software-intensive systems.TPS optimization is a challenging problem that determines the optimal size of thread pool dynamically on runtime.In case of distributed-TPS(DTPS),another issue is the load balancing b/w available set of TPSs running at backend servers.Existing DTPSs are overloaded either due to an inappropriate TPS optimization strategy at backend servers or improper load balancing scheme that cannot quickly recover an overload.Consequently,the performance of software-intensive system is suffered.Thus,in this paper,we propose a new DTPS that follows the collaborative round robin load balancing that has the effect of a double-edge sword.On the one hand,it effectively performs the load balancing(in case of overload situation)among available TPSs by a fast overload recovery procedure that decelerates the load on the overloaded TPSs up to their capacities and shifts the remaining load towards other gracefully running TPSs.And on the other hand,its robust load deceleration technique which is applied to an overloaded TPS sets an appropriate upper bound of thread pool size,because the pool size in each TPS is kept equal to the request rate on it,hence dynamically optimizes TPS.We evaluated the results of the proposed system against state of the art DTPSs by a clientserver based simulator and found that our system outperformed by sustaining smaller response times.展开更多
Validity of service in the service system is significantly affected by reliability of providers and availability of service contents. Most service inspiring schemes in pecr-to-pecr （P2P） networks associate each prov...Validity of service in the service system is significantly affected by reliability of providers and availability of service contents. Most service inspiring schemes in pecr-to-pecr （P2P） networks associate each provider with reputation or money to ensure provider＇s reliability so as to improve the availability of service contents. However, these schemes bring considerable risk to consumers when a provider with high reputation or money publishes a malicious service content. Moreover, the number of providers decreases as some providers are rejected while they have unconsciously published one or several polluted content., ever. The risk may spread to more users and cause the collapse of the service system. Recently, some researches have shown that the unconscious polluted contents are over twice as many as the intentional polluted contents. In order to distinguish the unconscious polluled contents from the intentional polluted contents and rescue those correlative users, we propose an audit model based on each service content to improve the validity of services. In our model, each node is associated with money, and each service content is associated with reputation. The unconscious polluted contents are prevented via consumers＇ evaluation, and the intentional polluted cantents and malicious providers are rejected via audit executors＇ evaluation. Simulatinn results show that the model improves the ratio of available service contents and reliable providers.展开更多
1.Background Crop diseases diminish potential yields by over 20%annually worldwide[1],driving a century-long quest to understand and harness genetic resistance in plants.The genetic basis of disease resistance was fir...1.Background Crop diseases diminish potential yields by over 20%annually worldwide[1],driving a century-long quest to understand and harness genetic resistance in plants.The genetic basis of disease resistance was first recognized in the early 1900s,when Biffen(1905)demonstrated that resistance to stripe rust in wheat(Triticum aestivum)followed Mendelian rules of inheritance[2].This foundational insight was later expanded by Flor(1942),who formulated the“gene-for-gene”model describing the genetic interplay between host resistance(R)genes and pathogen avirulence(Avr)genes[3].展开更多
Mimic active defense technology effectively disrupts attack routes and reduces the probability of successful attacks by using a dynamic heterogeneous redundancy(DHR)architecture.However,current approaches often overlo...Mimic active defense technology effectively disrupts attack routes and reduces the probability of successful attacks by using a dynamic heterogeneous redundancy(DHR)architecture.However,current approaches often overlook the adaptability of the adjudication mechanism in complex and variable network environments,focusing primarily on system security while neglecting performance considerations.To address these limitations,we propose an output difference feedback and system benefit control based DHR architecture.This architecture introduces an adjudication mechanism based on output difference feedback,which enhances adaptability by considering the impact of each executor's output deviation on the global decision.Additionally,the architecture incorporates a scheduling strategy based on system benefit,which models the quality of service and switching overhead as a bi-objective optimization problem,balancing security with reduced computational costs and system overhead.Simulation results demonstrate that our architecture improves adaptability towards different network environments and effectively reduces both the attack success rate and average failure rate.展开更多
The majority of plant disease resistance （R） genes encode proteins that share common structural features. However, the transcription activator-like effector （TALE）-associated executor type R genes show no consider...The majority of plant disease resistance （R） genes encode proteins that share common structural features. However, the transcription activator-like effector （TALE）-associated executor type R genes show no considerable sequence homology to any known R genes. We adopted a map-based cloning approach and TALE-based technology to isolate and characterize Xa23, a new executor R gene derived from wild rice （Oryza rufipogon） that confers an extremely broad spectrum of resistance to bacterial blight caused by Xanthomonas oryzae pv. oryzae （Xoo）. Xa23 encodes a 113 amino acid protein that shares 50% identity with the known executor R protein XA10. The predicted transmembrane helices in XA23 also overlap with those of XA10. Unlike XalO, however, Xa23 transcription is specifically activated by AvrXa23, a TALE present in all examined Xoo field isolates. Moreover, the susceptible xa23 allele has an identical open reading frame of Xa23 but differs in promoter region by lacking the TALE binding element （EBE） for AvrXa23. XA23 can trigger a strong hypersensitive response in rice, tobacco, and tomato. Our results provide the first evidence that plant genomes have an executor R gene family of which members execute their function and spectrum of disease resistance by recognizing the cognate TALEs in the pathogen.展开更多
Bacterial blight(BB)is a globally devastating rice disease caused by Xanthomonas oryzae pv.oryzae(Xoo).The use of disease resistance(R)genes in rice breeding is an effective and economical strategy for the control of ...Bacterial blight(BB)is a globally devastating rice disease caused by Xanthomonas oryzae pv.oryzae(Xoo).The use of disease resistance(R)genes in rice breeding is an effective and economical strategy for the control of this disease.Nevertheless,a majority of R genes lack durable resistance for long-term use under global warming conditions.Here,we report the isolation of a novel executor R gene,Xa7,that confers extremely durable,broad-spectrum,and heat-tolerant resistance to Xoo.The expression of Xa7 was induced by incompatible Xoo strains that secreted the transcription activator-like effector(TALE)AvrXa7 or PthXo3,which recognized effector binding elements(EBEs)in the Xa7 promoter.Furthermore,Xa7 induction was faster and stronger under high temperatures.Overexpression of Xa7 or co-transformation of Xa7 with avrXa7 triggered a hypersensitive response in plants.Constitutive expression of Xa7 activated a defense response in the absence of Xoo but inhibited the growth of transgenic rice plants.In addition,analysis of over 3000 rice varieties showed that the Xa7 locuswas found primarily in the indica and aus subgroups.A variation consisting of an 11-bp insertion and a base substitution(G to T)was found in EBEAvrXa7 in the tested varieties,resulting in a loss of Xa7 BB resistance.Through a decade of effort,we have identified an important BB resistance gene and characterized its distinctive interaction with Xoo strains;these findings will greatly facilitate research on the molecular mechanism of Xa7-mediated resistance and promote the use of this valuable gene in breeding.展开更多
China＇s emergency laws have emerged as a result of dealing with crises. They comprise laws and regulations, emergency plans, and military regulations, and define three exceptional or emergency states： war, emergency...China＇s emergency laws have emerged as a result of dealing with crises. They comprise laws and regulations, emergency plans, and military regulations, and define three exceptional or emergency states： war, emergency and emergency response, with the aim of constructing a comprehensive integrated system based on the specialized division of labor. In practice, however, emergency plans take the place of laws and regulations and provide the fundamental normative basis for tackling emergencies, with government and the military playing the dominant role. Developing out of necessity and possessing temporary applicability, China＇s emergency laws are characterized by authorization and prevention. Integrating emergency law with the socialist legal system with Chinese characteristics, formulating basic law for emergency situations and improving the specific mechanisms of emergency law should be regarded as major steps in its future development.展开更多
文摘开发Java Web项目中发现服务之间的调用存在超时情况,由于涉及的处理逻辑全部是异步,引入定时重试的机制,重试工具选择了JDK自带的Scheduled Thread Pool Executor。当A服务依赖B服务,B服务由于在业务高峰期处理能力降低,导致大量A服务过来的请求超时,A加入了超时重试机制,间隔时间根据重试次数的多少来决定,次数越多,两次重试之间间隔的时间越多,此时的业务高峰也会给A带来大量请求,大量的超时会导致重试队列迅速堆积,直到内存溢出。该文从线程池工作机制、Scheduled Thread Pool Executor实例的创建,获取重试任务的过程以及提交任务的过程角度分析,并通过源代码的剖析和测试工具My Eclipse进行演示测试内存泄露的情况,得出避免内存泄露的解决方案。
文摘Firstly analyzes the CHAOS and points out its shortages, and then uses the basic method—inspector/executor to deal with irregular computation, and offers the realization scheme for the CHAOS+ runtime library that supports irregular computation, and finally gives the node code program to show the example with CHAOS+ runtime library.
基金Supported by the Coal Union Fund of the National Nature Science Foundation of China （51174272） the Technology Innovation Fund of China Coal Science and Engineering Group （2012MS001）
文摘After analyzing the reasons for coal mine accidents and the current management methods, effective actions for the implementation of safety management were put forward by carrying out the whole process confirmation management. The ba- sic content and the five implementation steps were described, and the implementation method and the program of every step were introduced. Some rules for the implementation of the whole process confirmation management in coal mine safety pro- duction were explained, such as during the process of preproduction, before descent, descent, after descent, walking in the roadway, post-operation, shift, and hoisting after work. The results show that the guardians and the executors should both con- firm the implementation, which can improve the workers＇ attention and self-awareness to avoid errors in detail and reduce the ＂three violations＂ phenomenon. To ensure the effect of the whole process confirmation management, relevant departments should designate a person-in-charge in the specific work in all stages, make a work plan, and strengthen the internal evaluation.
文摘Scalability is one of the most important quality attribute of softwareintensive systems,because it maintains an effective performance parallel to the large fluctuating and sometimes unpredictable workload.In order to achieve scalability,thread pool system(TPS)(which is also known as executor service)has been used extensively as a middleware service in software-intensive systems.TPS optimization is a challenging problem that determines the optimal size of thread pool dynamically on runtime.In case of distributed-TPS(DTPS),another issue is the load balancing b/w available set of TPSs running at backend servers.Existing DTPSs are overloaded either due to an inappropriate TPS optimization strategy at backend servers or improper load balancing scheme that cannot quickly recover an overload.Consequently,the performance of software-intensive system is suffered.Thus,in this paper,we propose a new DTPS that follows the collaborative round robin load balancing that has the effect of a double-edge sword.On the one hand,it effectively performs the load balancing(in case of overload situation)among available TPSs by a fast overload recovery procedure that decelerates the load on the overloaded TPSs up to their capacities and shifts the remaining load towards other gracefully running TPSs.And on the other hand,its robust load deceleration technique which is applied to an overloaded TPS sets an appropriate upper bound of thread pool size,because the pool size in each TPS is kept equal to the request rate on it,hence dynamically optimizes TPS.We evaluated the results of the proposed system against state of the art DTPSs by a clientserver based simulator and found that our system outperformed by sustaining smaller response times.
基金National Natural Science Foundation of China(No.60903160)
文摘Validity of service in the service system is significantly affected by reliability of providers and availability of service contents. Most service inspiring schemes in pecr-to-pecr （P2P） networks associate each provider with reputation or money to ensure provider＇s reliability so as to improve the availability of service contents. However, these schemes bring considerable risk to consumers when a provider with high reputation or money publishes a malicious service content. Moreover, the number of providers decreases as some providers are rejected while they have unconsciously published one or several polluted content., ever. The risk may spread to more users and cause the collapse of the service system. Recently, some researches have shown that the unconscious polluted contents are over twice as many as the intentional polluted contents. In order to distinguish the unconscious polluled contents from the intentional polluted contents and rescue those correlative users, we propose an audit model based on each service content to improve the validity of services. In our model, each node is associated with money, and each service content is associated with reputation. The unconscious polluted contents are prevented via consumers＇ evaluation, and the intentional polluted cantents and malicious providers are rejected via audit executors＇ evaluation. Simulatinn results show that the model improves the ratio of available service contents and reliable providers.
基金supported by the National Natural Science Foundation of China(U21A20224)the Key Research and Development Program of Ministry of Science and Technology of China(2023YFD1200402)to Zhiyong Liu and by funding from King Abdullah University of Science and Technology to Brande B.H.Wulff.We thank Dr.Keyu Zhu(Institute of Genetics and Developmental Biology,Chinese Academy of Sciences)for helping to prepare the Figure.
文摘1.Background Crop diseases diminish potential yields by over 20%annually worldwide[1],driving a century-long quest to understand and harness genetic resistance in plants.The genetic basis of disease resistance was first recognized in the early 1900s,when Biffen(1905)demonstrated that resistance to stripe rust in wheat(Triticum aestivum)followed Mendelian rules of inheritance[2].This foundational insight was later expanded by Flor(1942),who formulated the“gene-for-gene”model describing the genetic interplay between host resistance(R)genes and pathogen avirulence(Avr)genes[3].
基金supported by the National Key R&D Program of China(Nos.2023YFB2904004 and 2023YFB2904000)the JiangsuKey Development Planning Project(No.BE2023004-2)+1 种基金the Natural Science Foundation of Jiangsu Province(Higher Education Institutions)(No.20KJA520001)the Postgraduate Research Practice Innovation Program of Jiangsu Province(No.KYCX22_1021)。
文摘Mimic active defense technology effectively disrupts attack routes and reduces the probability of successful attacks by using a dynamic heterogeneous redundancy(DHR)architecture.However,current approaches often overlook the adaptability of the adjudication mechanism in complex and variable network environments,focusing primarily on system security while neglecting performance considerations.To address these limitations,we propose an output difference feedback and system benefit control based DHR architecture.This architecture introduces an adjudication mechanism based on output difference feedback,which enhances adaptability by considering the impact of each executor's output deviation on the global decision.Additionally,the architecture incorporates a scheduling strategy based on system benefit,which models the quality of service and switching overhead as a bi-objective optimization problem,balancing security with reduced computational costs and system overhead.Simulation results demonstrate that our architecture improves adaptability towards different network environments and effectively reduces both the attack success rate and average failure rate.
文摘The majority of plant disease resistance （R） genes encode proteins that share common structural features. However, the transcription activator-like effector （TALE）-associated executor type R genes show no considerable sequence homology to any known R genes. We adopted a map-based cloning approach and TALE-based technology to isolate and characterize Xa23, a new executor R gene derived from wild rice （Oryza rufipogon） that confers an extremely broad spectrum of resistance to bacterial blight caused by Xanthomonas oryzae pv. oryzae （Xoo）. Xa23 encodes a 113 amino acid protein that shares 50% identity with the known executor R protein XA10. The predicted transmembrane helices in XA23 also overlap with those of XA10. Unlike XalO, however, Xa23 transcription is specifically activated by AvrXa23, a TALE present in all examined Xoo field isolates. Moreover, the susceptible xa23 allele has an identical open reading frame of Xa23 but differs in promoter region by lacking the TALE binding element （EBE） for AvrXa23. XA23 can trigger a strong hypersensitive response in rice, tobacco, and tomato. Our results provide the first evidence that plant genomes have an executor R gene family of which members execute their function and spectrum of disease resistance by recognizing the cognate TALEs in the pathogen.
基金supported by the Ministry of Agriculture and Rural Affairs of China(2016ZX08009003-001)the National Natural Science Foundation of China(32071987,31871605)the Natural Science Foundation of Zhejiang Province(LD19C130001).
文摘Bacterial blight(BB)is a globally devastating rice disease caused by Xanthomonas oryzae pv.oryzae(Xoo).The use of disease resistance(R)genes in rice breeding is an effective and economical strategy for the control of this disease.Nevertheless,a majority of R genes lack durable resistance for long-term use under global warming conditions.Here,we report the isolation of a novel executor R gene,Xa7,that confers extremely durable,broad-spectrum,and heat-tolerant resistance to Xoo.The expression of Xa7 was induced by incompatible Xoo strains that secreted the transcription activator-like effector(TALE)AvrXa7 or PthXo3,which recognized effector binding elements(EBEs)in the Xa7 promoter.Furthermore,Xa7 induction was faster and stronger under high temperatures.Overexpression of Xa7 or co-transformation of Xa7 with avrXa7 triggered a hypersensitive response in plants.Constitutive expression of Xa7 activated a defense response in the absence of Xoo but inhibited the growth of transgenic rice plants.In addition,analysis of over 3000 rice varieties showed that the Xa7 locuswas found primarily in the indica and aus subgroups.A variation consisting of an 11-bp insertion and a base substitution(G to T)was found in EBEAvrXa7 in the tested varieties,resulting in a loss of Xa7 BB resistance.Through a decade of effort,we have identified an important BB resistance gene and characterized its distinctive interaction with Xoo strains;these findings will greatly facilitate research on the molecular mechanism of Xa7-mediated resistance and promote the use of this valuable gene in breeding.
文摘China＇s emergency laws have emerged as a result of dealing with crises. They comprise laws and regulations, emergency plans, and military regulations, and define three exceptional or emergency states： war, emergency and emergency response, with the aim of constructing a comprehensive integrated system based on the specialized division of labor. In practice, however, emergency plans take the place of laws and regulations and provide the fundamental normative basis for tackling emergencies, with government and the military playing the dominant role. Developing out of necessity and possessing temporary applicability, China＇s emergency laws are characterized by authorization and prevention. Integrating emergency law with the socialist legal system with Chinese characteristics, formulating basic law for emergency situations and improving the specific mechanisms of emergency law should be regarded as major steps in its future development.
