The lack of fixed infrastructure in ad hoc networks causes nodes to rely more heavily on peer nodes for communication.Nevertheless,establishing trust in such a distributed environment is very difficult, since it is no...The lack of fixed infrastructure in ad hoc networks causes nodes to rely more heavily on peer nodes for communication.Nevertheless,establishing trust in such a distributed environment is very difficult, since it is not straightforward for a node to determine if its peer nodes can be trusted.An additional concern in such an environment is with whether a peer node is merely relaying a message or if it is the originator of the message.In this paper,we propose an authentication approach for protecting nodes in mobile ad hoc networks.The security requirements for protecting data link and network layers are identified and the design criteria for creating secure ad hoc networks using several authentication protocols are analyzed.Protocols based on zero knowledge and challenge response techniques are presented and their performance is evaluated through analysis and simulation.展开更多
In the past years, distributed computing is gaining the popularity due to reduction in execution time and low cost involvement. On the basis of this, Mobile Adhoc Network (MANET) is also increasing worldwide with majo...In the past years, distributed computing is gaining the popularity due to reduction in execution time and low cost involvement. On the basis of this, Mobile Adhoc Network (MANET) is also increasing worldwide with major advantage that it has no involvement of wire and transfer of data can be done by the virtual paths if the existing path is congested. In the present work, MANET is considered in the form of step topology which consists of heterogeneous collection of the devices. The work demonstrates the resources allocation for execution of tasks and it consists of selection of right path if the link failures and by pass link failures. It also consists of the resource management over the new proposed step topology. Entire work is modeled with the help of well known modeling language known as Unified Modeling Language (UML) and model demonstrates the resources allocation for execution of the tasks.展开更多
研究旨在让机器自动生成符合人类提问习惯的阶梯式问句链,辅助智能阅读提问、智能客服、智能医疗问诊等领域对于自然语言理解与生成任务的实际需求,提出一种基于知识图谱关系预测的阶梯式问句链生成模型(stepped question chain generat...研究旨在让机器自动生成符合人类提问习惯的阶梯式问句链,辅助智能阅读提问、智能客服、智能医疗问诊等领域对于自然语言理解与生成任务的实际需求,提出一种基于知识图谱关系预测的阶梯式问句链生成模型(stepped question chain generator based on knowledge graph link prediction,SQCG-KGLP)。SQCG-KGLP模型包括编码和解码两部分,在编码部分,对问句链的问句实体进行特征初始化,并通过特征融合方法获得问句链的融合头实体和待测尾实体的初始向量。将融合头实体和待测尾实体的初始向量送入SQCG-KGLP模型的Graph Attention图表示学习模块中,从而获得融合头实体和待测尾实体的表示向量。在解码部分,将融合头实体以及待测尾实体的表示向量输入到SQCG-KGLP模型的convKB模块中进行链接预测。在自建问句链数据集上进行不同跳数的实验,以MRR、Hits@1、Hits@3、Hits@10作为评测指标。结果表明,SQCG-KGLP算法均优于基线模型。当问句链生成迭代次数增加时,支持关系预测的知识图谱跳数随之增加,下一个节点问句语义信息表达的自然性会随之下降。此外,在现实应用场景中较难获得足量的高跳数问句训练数据集。目前,该研究仅能支持三跳以下的问句链生成。利用知识图谱的语义关联及知识图谱关系预测机制,生成的阶梯式问句链具有层层递进、由易到难、环环相扣的特点,使问句链的阶梯式逻辑质量更优。展开更多
以过氧化二异丙苯(DCP)为交联剂、三烯丙基异氰脲酸酯(TAIC)为助交联剂、偶氮二甲酰胺(AC)为发泡剂,采用一步法化学交联模压发泡制备聚丙烯发泡材料(EPP),考察不同塑化参数(温度和时间)与模压工艺(温度和时间)对EPP材料力学性能的影响...以过氧化二异丙苯(DCP)为交联剂、三烯丙基异氰脲酸酯(TAIC)为助交联剂、偶氮二甲酰胺(AC)为发泡剂,采用一步法化学交联模压发泡制备聚丙烯发泡材料(EPP),考察不同塑化参数(温度和时间)与模压工艺(温度和时间)对EPP材料力学性能的影响。结果表明,当DCP用量为1.2～1.4份,物料在130℃～140℃温度下塑化10 min 15min后,置于150℃～160℃平板硫化机中模压25 min～30min,可得到密度介于190 g/cm^3～240g/cm^3,且力学性能较优的EPP材料。偏光显微镜观察结果表明,当DCP用量为1.4份时,EPP材料的泡孔结构均匀且细密。展开更多
文摘The lack of fixed infrastructure in ad hoc networks causes nodes to rely more heavily on peer nodes for communication.Nevertheless,establishing trust in such a distributed environment is very difficult, since it is not straightforward for a node to determine if its peer nodes can be trusted.An additional concern in such an environment is with whether a peer node is merely relaying a message or if it is the originator of the message.In this paper,we propose an authentication approach for protecting nodes in mobile ad hoc networks.The security requirements for protecting data link and network layers are identified and the design criteria for creating secure ad hoc networks using several authentication protocols are analyzed.Protocols based on zero knowledge and challenge response techniques are presented and their performance is evaluated through analysis and simulation.
文摘In the past years, distributed computing is gaining the popularity due to reduction in execution time and low cost involvement. On the basis of this, Mobile Adhoc Network (MANET) is also increasing worldwide with major advantage that it has no involvement of wire and transfer of data can be done by the virtual paths if the existing path is congested. In the present work, MANET is considered in the form of step topology which consists of heterogeneous collection of the devices. The work demonstrates the resources allocation for execution of tasks and it consists of selection of right path if the link failures and by pass link failures. It also consists of the resource management over the new proposed step topology. Entire work is modeled with the help of well known modeling language known as Unified Modeling Language (UML) and model demonstrates the resources allocation for execution of the tasks.
文摘研究旨在让机器自动生成符合人类提问习惯的阶梯式问句链,辅助智能阅读提问、智能客服、智能医疗问诊等领域对于自然语言理解与生成任务的实际需求,提出一种基于知识图谱关系预测的阶梯式问句链生成模型(stepped question chain generator based on knowledge graph link prediction,SQCG-KGLP)。SQCG-KGLP模型包括编码和解码两部分,在编码部分,对问句链的问句实体进行特征初始化,并通过特征融合方法获得问句链的融合头实体和待测尾实体的初始向量。将融合头实体和待测尾实体的初始向量送入SQCG-KGLP模型的Graph Attention图表示学习模块中,从而获得融合头实体和待测尾实体的表示向量。在解码部分,将融合头实体以及待测尾实体的表示向量输入到SQCG-KGLP模型的convKB模块中进行链接预测。在自建问句链数据集上进行不同跳数的实验,以MRR、Hits@1、Hits@3、Hits@10作为评测指标。结果表明,SQCG-KGLP算法均优于基线模型。当问句链生成迭代次数增加时,支持关系预测的知识图谱跳数随之增加,下一个节点问句语义信息表达的自然性会随之下降。此外,在现实应用场景中较难获得足量的高跳数问句训练数据集。目前,该研究仅能支持三跳以下的问句链生成。利用知识图谱的语义关联及知识图谱关系预测机制,生成的阶梯式问句链具有层层递进、由易到难、环环相扣的特点,使问句链的阶梯式逻辑质量更优。
文摘以过氧化二异丙苯(DCP)为交联剂、三烯丙基异氰脲酸酯(TAIC)为助交联剂、偶氮二甲酰胺(AC)为发泡剂,采用一步法化学交联模压发泡制备聚丙烯发泡材料(EPP),考察不同塑化参数(温度和时间)与模压工艺(温度和时间)对EPP材料力学性能的影响。结果表明,当DCP用量为1.2～1.4份,物料在130℃～140℃温度下塑化10 min 15min后,置于150℃～160℃平板硫化机中模压25 min～30min,可得到密度介于190 g/cm^3～240g/cm^3,且力学性能较优的EPP材料。偏光显微镜观察结果表明,当DCP用量为1.4份时,EPP材料的泡孔结构均匀且细密。
