With the development of human society,the social hub enlarges beyond one community to the extent that the world is deemed as a community as a whole.Communication,therefore,plays an increasingly important role in our d...With the development of human society,the social hub enlarges beyond one community to the extent that the world is deemed as a community as a whole.Communication,therefore,plays an increasingly important role in our daily life.As a consequence,communication model or the definition of which is not so much a definition as a guide in communication.However,some existed communication models are not as practical as it was.This paper tries to make an overall contrast among three communication models——Coded Model,Gable's Communication Model and Ostensive Inferential Model,to see how they assist people to comprehend verbal and non-verbal communication.展开更多
The current study applied classic communication models to investigating 34 laureate impromptu speeches at the 2010 and 2011 "FLTRP (Foreign Language Teaching and Research Press) Cup" English Speaking Contest, one ...The current study applied classic communication models to investigating 34 laureate impromptu speeches at the 2010 and 2011 "FLTRP (Foreign Language Teaching and Research Press) Cup" English Speaking Contest, one of the most influential of its kind in China, to identify the features of public speaking skills of Advanced Chinese EFL learners. The speech scripts and video excerpts from the subsequent manuscript collection with the CD-Rom published by FLTRP were studied. Lucas' framework of speech communication process was borrowed to bridge elements of the communication models and speech delivery process. Three key aspects of the speakers' encoding endeavors were under close examination: the verbal preferences, the non-verbal preferences, and the topic selection for exemplification. It was found that successful speakers demonstrated a clear and strong audience orientation. They chose more first person pronouns, fewer abstract words, a controlled number of dependent clauses, clear transition words, and limited figures of speech. They used very few verbal fillers, slips of tongue, a moderate speech rate and varied tone inflections. The speakers also showed distinctive features in gestures, eye contact and facial expressions. They employed anecdotes which shared a common field of experience. Pedagogical implications on the teaching of public speaking were discussed.展开更多
This paper elaborates the core and essence of situation,background,assessment,recommendation(SBAR)communication model,clarify the application status of SBAR communication model in the clinical teaching of nursing stud...This paper elaborates the core and essence of situation,background,assessment,recommendation(SBAR)communication model,clarify the application status of SBAR communication model in the clinical teaching of nursing students,and describe its effectiveness and limitations,so as to provide reference for improving clinical nursing teaching ability.展开更多
This paper reports a five-year computer-mediated intercultural exchange project between Chinese and American university students that explores the use of various social media tools with WeChat application as the main ...This paper reports a five-year computer-mediated intercultural exchange project between Chinese and American university students that explores the use of various social media tools with WeChat application as the main medium in collaborative intercultural assignments. The study combines quantitative and qualitative approaches by using questionnaires and action research, to investigate how Chinese EFL and American CFL learners increase their intercultural communication competence by assessing their knowledge, awareness, attitudes, and skills of discovery and awareness. The findings reveal their changes and progress in the following variables: knowledge about the variety and subtlety of both the home and target cultures, a different worldview, and cultural study methods;awareness of the importance of differences and similarities between the home and target cultures, their negative reactions to these differences(e.g., fear, ridicule, disgust, feeling of superiority, etc.) and therefore, critical evaluation of the target and home cultures;attitudes from excitement or blind admiration of the target culture to confusion, anxiety or frustration about the cultural differences, later to toleration and appreciation of cultural differences, adaptation to the target culture, and eventually to openness and readiness to suspend disbelief about other cultures and belief about one’s own;skills to contrast the target culture with their own, to demonstrate a capacity to interact appropriately in a variety of different social situations in the target culture and resolve cross-cultural conflicts and misunderstandings. This research will serve as a valuable reference for computer-mediated intercultural communication teaching and open up new possibilities to extend classroom teaching by bridging the gap between second-hand knowledge and hands-on experience.展开更多
For the multipath fading on electromagnetic waves of wireless communication in the confined areas,the rectangular tunnel cooperative communication system was established based on the multimode channel model and the ch...For the multipath fading on electromagnetic waves of wireless communication in the confined areas,the rectangular tunnel cooperative communication system was established based on the multimode channel model and the channel capacity formula derivation was obtained.On the optimal criterion of the channel capacity,the power allocation methods of both amplifying and forwarding(AF) and decoding and forwarding(DF) cooperative communication systems were proposed in the limitation of the total power to maximize the channel capacity.The mode selection methods of single input single output(SISO) and single input multiple output(SIMO) models in the rectangular tunnel,through which the higher channel capacity can be obtained,were put forward as well.The theoretical analysis and simulation comparison show that,channel capacity of the wireless communication system in the rectangular tunnel can be effectively enhanced through the cooperative technology;channel capacity of the rectangular tunnel under complicated conditions is maximized through the proposed power allocation methods,and the optimal cooperative mode of the channel capacity can be chosen according to the cooperative mode selection methods given in the paper.展开更多
Nowadays,the communication of traditional culture is facing various challenges,including limitations of traditional culture itself,decrease of inheritors,poor construction of structure,and heterization of connotation,...Nowadays,the communication of traditional culture is facing various challenges,including limitations of traditional culture itself,decrease of inheritors,poor construction of structure,and heterization of connotation,as well as conflicts between Chinese and foreign cultures in the context of globalization.New media has provided more opportunities for the communication of outstanding Chinese traditional culture.This paper analyzed the role of new media in completing the structure and expanding the scope of communication of outstanding Chinese traditional culture,and proposed strategy for optimizing the communication route from the perspective of improving environment,changing content,and adjusting strategy.The contributions of new media to the communication of Chinese traditional culture should be highly appreciated.展开更多
While studying communication,researchers and practitioners may use different theoretical approaches or models representative of the process.Dependent on the definition of communication and the use of a linear,interact...While studying communication,researchers and practitioners may use different theoretical approaches or models representative of the process.Dependent on the definition of communication and the use of a linear,interactional or transactional model of communication,the philosophical inclination will change,as well as the questions,hypothesis,and explanations formulated by the professional.Communication takes place in diverse contexts;this text focuses on interpersonal communication settings.Interpersonal communication may become atypical when one of the parties in the exchange communicates mainly through pre-verbal,unconventional and,sometimes,peculiar behaviours.Atypical communication is common in case of a disability or neurodevelopmental condition is present.In the present research,the Complex of Continuous Communication(CCC)is formulated as a theoretical model to analyse and explain atypical interpersonal communication as a co-creative process,emphasizing the way the communication relationship is developed within the dyads.The model is based on a thorough narrative review of relevant literature in the field to determine the components of the model,clarify the relationships among them,and explain how the communicative dynamic may grow in terms of diversity and complexity.The new model is articulated with a conscious influence from the transactional conceptualization and the dialogical perspective of communication,acknowledging the need for further experimentation in order to be validated.展开更多
The article is commonly about the impact of globalization on participants of pedagogical process in the condition of communication. The globalization leaves its tracks in separate spheres of the educational system as ...The article is commonly about the impact of globalization on participants of pedagogical process in the condition of communication. The globalization leaves its tracks in separate spheres of the educational system as well as it impacts all spheres of modern life. The relation between a teacher and a student differs with its peculiarity in the contemporary life. A pupil or a student differs totally in classifying the information gained in his activity. A modem student demonstrates a special attitude to everyday events and gets an independent position. Such reality demands the teacher of the day to have a very high practice; the necessity of contemporary training in the process of training-education can be marked as the appearance of globalization. It occurs as a demand for globalization as well. All these items after being analyzed bring some conclusions.展开更多
While cellular networks have continuously evolved in re- cent years, the industry has clearly seen unprecedented chal- lenges to meet the exponentially growing expectations in the near future. The 5G system is facing ...While cellular networks have continuously evolved in re- cent years, the industry has clearly seen unprecedented chal- lenges to meet the exponentially growing expectations in the near future. The 5G system is facing grand challenges such as the ever-increasing traffic volumes and remarkably diver- sified services connecting humans and machines alike. As a result, the future network has to deliver massively increased capacity, greater flexibility, incorporated computing capabili- ty, support of significantly extended battery lifetime, and ac- commodation of varying payloads with fast setup and low latency, etc. In particular, as 5G requires more spectrum resource, higher frequency bands are desirable. Nowadays, millimeter wave has been widely accepted as one of the main communication bands for 5G.展开更多
While cellular networks have continuously evolved in recent years, the industry has clearly seen unprecedented challenges to meet the exponentially growing expectations in the near future.
With the rapid spread of smart sensors,data collection is becoming more and more important in Mobile Edge Networks(MENs).The collected data can be used in many applications based on the analysis results of these data ...With the rapid spread of smart sensors,data collection is becoming more and more important in Mobile Edge Networks(MENs).The collected data can be used in many applications based on the analysis results of these data by cloud computing.Nowadays,data collection schemes have been widely studied by researchers.However,most of the researches take the amount of collected data into consideration without thinking about the problem of privacy leakage of the collected data.In this paper,we propose an energy-efficient and anonymous data collection scheme for MENs to keep a balance between energy consumption and data privacy,in which the privacy information of senors is hidden during data communication.In addition,the residual energy of nodes is taken into consideration in this scheme in particular when it comes to the selection of the relay node.The security analysis shows that no privacy information of the source node and relay node is leaked to attackers.Moreover,the simulation results demonstrate that the proposed scheme is better than other schemes in aspects of lifetime and energy consumption.At the end of the simulation part,we present a qualitative analysis for the proposed scheme and some conventional protocols.It is noteworthy that the proposed scheme outperforms the existing protocols in terms of the above indicators.展开更多
Space information network is used for real time acquiring, transmitting and processing the space information on the space platform, which provides significant communication services for communication, navigation posit...Space information network is used for real time acquiring, transmitting and processing the space information on the space platform, which provides significant communication services for communication, navigation positioning and science exploration. In this paper, the architecture of Software Defined Space Optical Network (SDSON) based on cloud platform is designed by means of Software Defined Optical Network (SDON) and cloud services. The new architecture combining centralized and distributed management-control mechanism is a multi-layer and multi-domain architecture with powerful computing and storage ability. Moreover, reliable service and unreliable service communication models employed in the space information network are proposed considering the characteristic of Disruption/Delay Tolerant Network (DTN). Finally, the functional verification and demonstration are performed on our optical experimental network platform.展开更多
The TEM-4 is important for English majors in colleges,and mock examination is a common mean to increase the passing rate.The studies that focus on the TEM-4 are much more than that of the mock one of TEM-4 even the la...The TEM-4 is important for English majors in colleges,and mock examination is a common mean to increase the passing rate.The studies that focus on the TEM-4 are much more than that of the mock one of TEM-4 even the latter can be regarded as an effective measure from the pedagogical prospective.This study,hence,paid attention to the mock test of TEM-4 by describing and analyzing the data collected from 24 subjects and found the relationship between reading section and multiple-choice section.The study also provided some suggestion of how to make good use of the mock test to improve the language competence of students.展开更多
Message passing interface (MPI) is the de facto standard in writing parallel scientific applications on distributed memory systems. Performance prediction of MPI programs on current or future parallel systems can he...Message passing interface (MPI) is the de facto standard in writing parallel scientific applications on distributed memory systems. Performance prediction of MPI programs on current or future parallel systems can help to find system bottleneck or optimize programs. To effectively analyze and predict performance of a large and complex MPI program, an efficient and accurate communication model is highly needed. A series of communication models have been proposed, such as the LogP model family, which assume that the sending overhead, message transmission, and receiving overhead of a communication is not overlapped and there is a maximum overlap degree between computation and communication. However, this assumption does not always hold for MPI programs because either sending or receiving overhead introduced by MPI implementations can decrease potential overlap for large messages. In this paper, we present a new communication model, named LogGPO, which captures the potential overlap between computation with communication of MPI programs. We design and implement a trace-driven simulator to verify the LogGPO model by predicting performance of point-to-point communication and two real applications CG and Sweep3D. The average prediction errors of LogGPO model are 2.4% and 2.0% for these two applications respectively, while the average prediction errors of LogGP model are 38.3% and 9.1% respectively.展开更多
IP covert timing channel (IPCTC) is an unconventional communication channel which attaches time information to the packets of an overt channel as messages carders, e.g., using different inter-packet delays to transm...IP covert timing channel (IPCTC) is an unconventional communication channel which attaches time information to the packets of an overt channel as messages carders, e.g., using different inter-packet delays to transmit messages in a packet-switched network. Although the IPCTCs have many different communication methods, based on the concept of time, we categorized the base communication model of the IPCTCs into three types and then utilized the signal processing theory to build their mathematical models. As a result, the basic characteristics of the IPCTCs' base model were formally derived. Hence, the characteristics of any IPCTC can be derived from the base models that consist of the IPCTC. Furthermore, a set of approaches was devised to implement the base model of the IPCTCs in a TCP/IP network. Experimental results show the correctness of the pro- posed base model of the IPCTCs in this paper.展开更多
To overcome the drawback of a short operation range and low-resolution of a passive location system using a civil communication signal, the new idea that utilizes code division multiple access (CDMA) signal and repe...To overcome the drawback of a short operation range and low-resolution of a passive location system using a civil communication signal, the new idea that utilizes code division multiple access (CDMA) signal and repeater is disposed off. First, the CDMA passive location model and observation function are given, and the error source and error range are analyzed. Subsequently, the CDMA passive location algorithm in a repeater environment is described and simulated. The simulation result shows that the algorithm can provide the location value with high accuracy.展开更多
For the performance issues of satellite transceivers suffering passive intermodulation interference,a novel and effective digital suppression algorithm is presented in this paper.In contrast to analog approaches,digit...For the performance issues of satellite transceivers suffering passive intermodulation interference,a novel and effective digital suppression algorithm is presented in this paper.In contrast to analog approaches,digital passive intermodulation(PIM) suppression approaches can be easily reconfigured and therefore are highly attractive for future satellite communication systems.A simplified model of nonlinear distortion from passive microwave devices is established in consideration of the memory effect.The multiple high-order PIM products falling into the receiving band can be described as a bilinear predictor function.A suppression algorithm based on a bilinear polynomial decorrelated adaptive filter is proposed for baseband digital signal processing.In consideration of the time-varying characteristics of passive intermodulation,this algorithm can achieve the rapidness of online interference estimation and low complexity with less consumption of resources.Numerical simulation results show that the algorithm can effectively compensate the passive intermodulation interference,and achieve a high signal-to-interference ratio gain.展开更多
文摘With the development of human society,the social hub enlarges beyond one community to the extent that the world is deemed as a community as a whole.Communication,therefore,plays an increasingly important role in our daily life.As a consequence,communication model or the definition of which is not so much a definition as a guide in communication.However,some existed communication models are not as practical as it was.This paper tries to make an overall contrast among three communication models——Coded Model,Gable's Communication Model and Ostensive Inferential Model,to see how they assist people to comprehend verbal and non-verbal communication.
基金supported by the Fundamental Research Funds for the Central Universities(2011WC033)the High Level Fundamental Research Funds for the Development of Foreign Language Discipline of HUST(Huazhong University of Science and Technology)
文摘The current study applied classic communication models to investigating 34 laureate impromptu speeches at the 2010 and 2011 "FLTRP (Foreign Language Teaching and Research Press) Cup" English Speaking Contest, one of the most influential of its kind in China, to identify the features of public speaking skills of Advanced Chinese EFL learners. The speech scripts and video excerpts from the subsequent manuscript collection with the CD-Rom published by FLTRP were studied. Lucas' framework of speech communication process was borrowed to bridge elements of the communication models and speech delivery process. Three key aspects of the speakers' encoding endeavors were under close examination: the verbal preferences, the non-verbal preferences, and the topic selection for exemplification. It was found that successful speakers demonstrated a clear and strong audience orientation. They chose more first person pronouns, fewer abstract words, a controlled number of dependent clauses, clear transition words, and limited figures of speech. They used very few verbal fillers, slips of tongue, a moderate speech rate and varied tone inflections. The speakers also showed distinctive features in gestures, eye contact and facial expressions. They employed anecdotes which shared a common field of experience. Pedagogical implications on the teaching of public speaking were discussed.
基金Qingdao Binhai University,2021 Shandong Province Undergraduate and Teaching Reform Key Project Z2021037。
文摘This paper elaborates the core and essence of situation,background,assessment,recommendation(SBAR)communication model,clarify the application status of SBAR communication model in the clinical teaching of nursing students,and describe its effectiveness and limitations,so as to provide reference for improving clinical nursing teaching ability.
文摘This paper reports a five-year computer-mediated intercultural exchange project between Chinese and American university students that explores the use of various social media tools with WeChat application as the main medium in collaborative intercultural assignments. The study combines quantitative and qualitative approaches by using questionnaires and action research, to investigate how Chinese EFL and American CFL learners increase their intercultural communication competence by assessing their knowledge, awareness, attitudes, and skills of discovery and awareness. The findings reveal their changes and progress in the following variables: knowledge about the variety and subtlety of both the home and target cultures, a different worldview, and cultural study methods;awareness of the importance of differences and similarities between the home and target cultures, their negative reactions to these differences(e.g., fear, ridicule, disgust, feeling of superiority, etc.) and therefore, critical evaluation of the target and home cultures;attitudes from excitement or blind admiration of the target culture to confusion, anxiety or frustration about the cultural differences, later to toleration and appreciation of cultural differences, adaptation to the target culture, and eventually to openness and readiness to suspend disbelief about other cultures and belief about one’s own;skills to contrast the target culture with their own, to demonstrate a capacity to interact appropriately in a variety of different social situations in the target culture and resolve cross-cultural conflicts and misunderstandings. This research will serve as a valuable reference for computer-mediated intercultural communication teaching and open up new possibilities to extend classroom teaching by bridging the gap between second-hand knowledge and hands-on experience.
基金financial supports provided by the National Natural Science Foundation of China (No.51274202)the Fundamental Research Funds for the Central Universities (No.2013RC11)+3 种基金the Science and Technology Achievements Transformation Project of Jiangsu Province (No.BA2012068)the Natural Science Foundation of Jiangsu Province (Nos.BK20130199 and BK20131124)Ceeusro Prospective Joint Research Project of Jiangsu Province (No.BY2014028-01)Great Cultivating Special Project at China University of Mining and Technology (No.2014ZDPY16)
文摘For the multipath fading on electromagnetic waves of wireless communication in the confined areas,the rectangular tunnel cooperative communication system was established based on the multimode channel model and the channel capacity formula derivation was obtained.On the optimal criterion of the channel capacity,the power allocation methods of both amplifying and forwarding(AF) and decoding and forwarding(DF) cooperative communication systems were proposed in the limitation of the total power to maximize the channel capacity.The mode selection methods of single input single output(SISO) and single input multiple output(SIMO) models in the rectangular tunnel,through which the higher channel capacity can be obtained,were put forward as well.The theoretical analysis and simulation comparison show that,channel capacity of the wireless communication system in the rectangular tunnel can be effectively enhanced through the cooperative technology;channel capacity of the rectangular tunnel under complicated conditions is maximized through the proposed power allocation methods,and the optimal cooperative mode of the channel capacity can be chosen according to the cooperative mode selection methods given in the paper.
基金the research findings of the research project of Sichuan International Studies University(Serial number:Sisu2019016)Project Title The Impact of New Media Hotspots on Urban Tourism
文摘Nowadays,the communication of traditional culture is facing various challenges,including limitations of traditional culture itself,decrease of inheritors,poor construction of structure,and heterization of connotation,as well as conflicts between Chinese and foreign cultures in the context of globalization.New media has provided more opportunities for the communication of outstanding Chinese traditional culture.This paper analyzed the role of new media in completing the structure and expanding the scope of communication of outstanding Chinese traditional culture,and proposed strategy for optimizing the communication route from the perspective of improving environment,changing content,and adjusting strategy.The contributions of new media to the communication of Chinese traditional culture should be highly appreciated.
基金financially supported by National Funds through Fundação para a Ciência e a Tecnologia(FCT),I.P.,under the project UIDB/04279/2020.
文摘While studying communication,researchers and practitioners may use different theoretical approaches or models representative of the process.Dependent on the definition of communication and the use of a linear,interactional or transactional model of communication,the philosophical inclination will change,as well as the questions,hypothesis,and explanations formulated by the professional.Communication takes place in diverse contexts;this text focuses on interpersonal communication settings.Interpersonal communication may become atypical when one of the parties in the exchange communicates mainly through pre-verbal,unconventional and,sometimes,peculiar behaviours.Atypical communication is common in case of a disability or neurodevelopmental condition is present.In the present research,the Complex of Continuous Communication(CCC)is formulated as a theoretical model to analyse and explain atypical interpersonal communication as a co-creative process,emphasizing the way the communication relationship is developed within the dyads.The model is based on a thorough narrative review of relevant literature in the field to determine the components of the model,clarify the relationships among them,and explain how the communicative dynamic may grow in terms of diversity and complexity.The new model is articulated with a conscious influence from the transactional conceptualization and the dialogical perspective of communication,acknowledging the need for further experimentation in order to be validated.
文摘The article is commonly about the impact of globalization on participants of pedagogical process in the condition of communication. The globalization leaves its tracks in separate spheres of the educational system as well as it impacts all spheres of modern life. The relation between a teacher and a student differs with its peculiarity in the contemporary life. A pupil or a student differs totally in classifying the information gained in his activity. A modem student demonstrates a special attitude to everyday events and gets an independent position. Such reality demands the teacher of the day to have a very high practice; the necessity of contemporary training in the process of training-education can be marked as the appearance of globalization. It occurs as a demand for globalization as well. All these items after being analyzed bring some conclusions.
文摘While cellular networks have continuously evolved in re- cent years, the industry has clearly seen unprecedented chal- lenges to meet the exponentially growing expectations in the near future. The 5G system is facing grand challenges such as the ever-increasing traffic volumes and remarkably diver- sified services connecting humans and machines alike. As a result, the future network has to deliver massively increased capacity, greater flexibility, incorporated computing capabili- ty, support of significantly extended battery lifetime, and ac- commodation of varying payloads with fast setup and low latency, etc. In particular, as 5G requires more spectrum resource, higher frequency bands are desirable. Nowadays, millimeter wave has been widely accepted as one of the main communication bands for 5G.
文摘While cellular networks have continuously evolved in recent years, the industry has clearly seen unprecedented challenges to meet the exponentially growing expectations in the near future.
基金This work is supported by the National Key R&D Program of China under Grant No.2018YFB0505000the National Natural Science Foundation of China under Grant No.U1836115,No.61922045,No.U1836115 and No.61672295+2 种基金the Natural Science Foundation of Jiangsu Province under Grant No.BK20181408the State Key Laboratory of Cryptology Foundation,Guangxi Key Laboratory of Cryptography and Information Security No.GCIS201715the CICAEET fund,and the PAPD fund.
文摘With the rapid spread of smart sensors,data collection is becoming more and more important in Mobile Edge Networks(MENs).The collected data can be used in many applications based on the analysis results of these data by cloud computing.Nowadays,data collection schemes have been widely studied by researchers.However,most of the researches take the amount of collected data into consideration without thinking about the problem of privacy leakage of the collected data.In this paper,we propose an energy-efficient and anonymous data collection scheme for MENs to keep a balance between energy consumption and data privacy,in which the privacy information of senors is hidden during data communication.In addition,the residual energy of nodes is taken into consideration in this scheme in particular when it comes to the selection of the relay node.The security analysis shows that no privacy information of the source node and relay node is leaked to attackers.Moreover,the simulation results demonstrate that the proposed scheme is better than other schemes in aspects of lifetime and energy consumption.At the end of the simulation part,we present a qualitative analysis for the proposed scheme and some conventional protocols.It is noteworthy that the proposed scheme outperforms the existing protocols in terms of the above indicators.
文摘Space information network is used for real time acquiring, transmitting and processing the space information on the space platform, which provides significant communication services for communication, navigation positioning and science exploration. In this paper, the architecture of Software Defined Space Optical Network (SDSON) based on cloud platform is designed by means of Software Defined Optical Network (SDON) and cloud services. The new architecture combining centralized and distributed management-control mechanism is a multi-layer and multi-domain architecture with powerful computing and storage ability. Moreover, reliable service and unreliable service communication models employed in the space information network are proposed considering the characteristic of Disruption/Delay Tolerant Network (DTN). Finally, the functional verification and demonstration are performed on our optical experimental network platform.
文摘The TEM-4 is important for English majors in colleges,and mock examination is a common mean to increase the passing rate.The studies that focus on the TEM-4 are much more than that of the mock one of TEM-4 even the latter can be regarded as an effective measure from the pedagogical prospective.This study,hence,paid attention to the mock test of TEM-4 by describing and analyzing the data collected from 24 subjects and found the relationship between reading section and multiple-choice section.The study also provided some suggestion of how to make good use of the mock test to improve the language competence of students.
基金Supported by the National High-Tech Research & Development Program of China (Grant No. 2006AA01A105)
文摘Message passing interface (MPI) is the de facto standard in writing parallel scientific applications on distributed memory systems. Performance prediction of MPI programs on current or future parallel systems can help to find system bottleneck or optimize programs. To effectively analyze and predict performance of a large and complex MPI program, an efficient and accurate communication model is highly needed. A series of communication models have been proposed, such as the LogP model family, which assume that the sending overhead, message transmission, and receiving overhead of a communication is not overlapped and there is a maximum overlap degree between computation and communication. However, this assumption does not always hold for MPI programs because either sending or receiving overhead introduced by MPI implementations can decrease potential overlap for large messages. In this paper, we present a new communication model, named LogGPO, which captures the potential overlap between computation with communication of MPI programs. We design and implement a trace-driven simulator to verify the LogGPO model by predicting performance of point-to-point communication and two real applications CG and Sweep3D. The average prediction errors of LogGPO model are 2.4% and 2.0% for these two applications respectively, while the average prediction errors of LogGP model are 38.3% and 9.1% respectively.
基金This work was supported in part by the National Nature Science Foundation of China (Grant Nos. 61300228 and 61672269), Jiangsu Technology Support Project (BE2013103, BA2015161) Bajian Project of Jiangsu University (1213000013).
文摘IP covert timing channel (IPCTC) is an unconventional communication channel which attaches time information to the packets of an overt channel as messages carders, e.g., using different inter-packet delays to transmit messages in a packet-switched network. Although the IPCTCs have many different communication methods, based on the concept of time, we categorized the base communication model of the IPCTCs into three types and then utilized the signal processing theory to build their mathematical models. As a result, the basic characteristics of the IPCTCs' base model were formally derived. Hence, the characteristics of any IPCTC can be derived from the base models that consist of the IPCTC. Furthermore, a set of approaches was devised to implement the base model of the IPCTCs in a TCP/IP network. Experimental results show the correctness of the pro- posed base model of the IPCTCs in this paper.
基金the Key Project of Ministry of Education (207097)Education Natural Science Foundation Project of CQCSTC (2006BB2376)
文摘To overcome the drawback of a short operation range and low-resolution of a passive location system using a civil communication signal, the new idea that utilizes code division multiple access (CDMA) signal and repeater is disposed off. First, the CDMA passive location model and observation function are given, and the error source and error range are analyzed. Subsequently, the CDMA passive location algorithm in a repeater environment is described and simulated. The simulation result shows that the algorithm can provide the location value with high accuracy.
基金supported by the National Natural SciencFoundation of China(Nos.U1636125,61601027)
文摘For the performance issues of satellite transceivers suffering passive intermodulation interference,a novel and effective digital suppression algorithm is presented in this paper.In contrast to analog approaches,digital passive intermodulation(PIM) suppression approaches can be easily reconfigured and therefore are highly attractive for future satellite communication systems.A simplified model of nonlinear distortion from passive microwave devices is established in consideration of the memory effect.The multiple high-order PIM products falling into the receiving band can be described as a bilinear predictor function.A suppression algorithm based on a bilinear polynomial decorrelated adaptive filter is proposed for baseband digital signal processing.In consideration of the time-varying characteristics of passive intermodulation,this algorithm can achieve the rapidness of online interference estimation and low complexity with less consumption of resources.Numerical simulation results show that the algorithm can effectively compensate the passive intermodulation interference,and achieve a high signal-to-interference ratio gain.