ISSN 
2014 Vol. 43, No. 1
2014, 43(1): 1-5.
doi: 10.3969/j.issn.1001-0548.2014.01.001
Abstract:
This article is an edited report from a workshop on complex networks organized by the Hangzhou Normal University in 2013, where ten challenging research problems in the field of network science were identified through collective discussions. These ten issues are formulated from the active complex networks research in the present big-data era, aiming to provide important research directions along with sensible suggestions and recommendations to young scholars with potential contributions into future research on complex networks.
This article is an edited report from a workshop on complex networks organized by the Hangzhou Normal University in 2013, where ten challenging research problems in the field of network science were identified through collective discussions. These ten issues are formulated from the active complex networks research in the present big-data era, aiming to provide important research directions along with sensible suggestions and recommendations to young scholars with potential contributions into future research on complex networks.
2014, 43(1): 7-20.
doi: 10.3969/j.issn.1001-0548.2014.01.002
Abstract:
In this paper, a variety of fundamental construction algorithms of null model for un-weighted networks, weighted networks, and temporal networks have been reviewed, especially the construction of null models based on randomized algorithms and their practical applications have been summarized. Randomized algorithms can not only rewire edges of networks, but also randomize some factors on the condition of keeping the original connection. By analyzing and comparing randomized algorithms, this study is helpful for researchers to know how to use randomized algorithms to construct null models of complex networks, and this study is useful to calculate relative values of various statistics by comparing the original network with its null model. Furthermore, this work can deepen our understanding and utilizing various complex systems.
In this paper, a variety of fundamental construction algorithms of null model for un-weighted networks, weighted networks, and temporal networks have been reviewed, especially the construction of null models based on randomized algorithms and their practical applications have been summarized. Randomized algorithms can not only rewire edges of networks, but also randomize some factors on the condition of keeping the original connection. By analyzing and comparing randomized algorithms, this study is helpful for researchers to know how to use randomized algorithms to construct null models of complex networks, and this study is useful to calculate relative values of various statistics by comparing the original network with its null model. Furthermore, this work can deepen our understanding and utilizing various complex systems.
2014, 43(1): 21-25.
doi: 10.3969/j.issn.1001-0548.2014.01.003
Abstract:
In this paper we study the impacts of social reinforcement, edge weight, and the non-locality effect of network on information spreading. Intimacy between two nodes is defined as the number of their common neighbors, and edge weight is defined based on its intimacy. We show that when an individual has the larger tendency to accept information from close friend, the less likely a wide range of information dissemination, in other words, strong ties will reduce the range of propagation. On the contrary, when an individual has the larger tendency to accept information from estranged friend, the more likely a wide range of information dissemination, in other words, weak ties will enlarge propagation. Meanwhile, we find that when the social reinforcement strength is small, information transmission in the random networks will have wider spread range than in the regular networks. Otherwise, the result will be opposite.
In this paper we study the impacts of social reinforcement, edge weight, and the non-locality effect of network on information spreading. Intimacy between two nodes is defined as the number of their common neighbors, and edge weight is defined based on its intimacy. We show that when an individual has the larger tendency to accept information from close friend, the less likely a wide range of information dissemination, in other words, strong ties will reduce the range of propagation. On the contrary, when an individual has the larger tendency to accept information from estranged friend, the more likely a wide range of information dissemination, in other words, weak ties will enlarge propagation. Meanwhile, we find that when the social reinforcement strength is small, information transmission in the random networks will have wider spread range than in the regular networks. Otherwise, the result will be opposite.
2014, 43(1): 26-30,41.
doi: 10.3969/j.issn.1001-0548.2014.01.004
Abstract:
Multi-base station cooperative communication can efficiently reduce the inter-cell interference, but its power allocation is a non-convex optimization problem. In this paper, we formulate the power allocation as a signal-to-interference-plus-noise-ratio (SINR) balancing problem and propose a scheme to solve the problem in its equivalent form. Based on genetic algorithm, the proposed power allocation scheme sets the path loss threshold to select the cooperative base stations for each user and considers different users' SINR fairness. Numerical results show that the proposed power allocation scheme will increase each user's average SINR about 17.75dB and 2.36dB in the same conditions of adopting equal power allocation of traditional cellular system and equal power allocation of multi-base cooperative communication system, respectively.
Multi-base station cooperative communication can efficiently reduce the inter-cell interference, but its power allocation is a non-convex optimization problem. In this paper, we formulate the power allocation as a signal-to-interference-plus-noise-ratio (SINR) balancing problem and propose a scheme to solve the problem in its equivalent form. Based on genetic algorithm, the proposed power allocation scheme sets the path loss threshold to select the cooperative base stations for each user and considers different users' SINR fairness. Numerical results show that the proposed power allocation scheme will increase each user's average SINR about 17.75dB and 2.36dB in the same conditions of adopting equal power allocation of traditional cellular system and equal power allocation of multi-base cooperative communication system, respectively.
2014, 43(1): 31-35.
doi: 10.3969/j.issn.1001-0548.2014.01.005
Abstract:
The rate of coal desulphurization can be promoted by microwave irradiation much more, which have be recognized and validated from recent experiment results. However, there still exist many unanswered questions, which creates significant limit on its development. To investigate the best frequency for such a microwave reaction, a frequency reconfigurable microwave reaction experiment apparatus is proposed and designed in this paper, including a wideband microwave source, a wideband microwave transmission system, and a frequency reconfigurable reactor. This apparatus offers a 67% tunable bandwidth to cover the operation frequency range of 500 ～ 1 000 MHz. Compared with other reaction apparatus with the same function, our design is simple and low cost. Furthermore, it can be employed in other microwave chemical experiments.
The rate of coal desulphurization can be promoted by microwave irradiation much more, which have be recognized and validated from recent experiment results. However, there still exist many unanswered questions, which creates significant limit on its development. To investigate the best frequency for such a microwave reaction, a frequency reconfigurable microwave reaction experiment apparatus is proposed and designed in this paper, including a wideband microwave source, a wideband microwave transmission system, and a frequency reconfigurable reactor. This apparatus offers a 67% tunable bandwidth to cover the operation frequency range of 500 ～ 1 000 MHz. Compared with other reaction apparatus with the same function, our design is simple and low cost. Furthermore, it can be employed in other microwave chemical experiments.
2014, 43(1): 36-41.
doi: 10.3969/j.issn.1001-0548.2014.01.006
Abstract:
According to the problem of the ‘three crossing’ motions and compensations for the ground moving target of high speed moving multi-input and multi-output (MIMO) radar, a space model is established and the equations of delay and transmit pattern which is changing with time and period are educed. The echo characteristics are analyzed and the formulas of ‘three crossing’ are derived. A compensation method is proposed by using pre-process to compensate crossing range-cell and crossing-beam and by applying FrFT to compensate crossing Doppler-cell. The method could compensate ‘three crossing’ simultaneously with much less calculating quantities than methods presented before as pre-process of the transmit signals. At last, the phantom antenna array is used in the simulations, and the ‘sparse transmit dense receive’ is applied to the simulation of crossing-beam and its compensation. The results of simulations demonstrate the validity of the method combining pre-process and FrFT to compensate ‘three crossing’.
According to the problem of the ‘three crossing’ motions and compensations for the ground moving target of high speed moving multi-input and multi-output (MIMO) radar, a space model is established and the equations of delay and transmit pattern which is changing with time and period are educed. The echo characteristics are analyzed and the formulas of ‘three crossing’ are derived. A compensation method is proposed by using pre-process to compensate crossing range-cell and crossing-beam and by applying FrFT to compensate crossing Doppler-cell. The method could compensate ‘three crossing’ simultaneously with much less calculating quantities than methods presented before as pre-process of the transmit signals. At last, the phantom antenna array is used in the simulations, and the ‘sparse transmit dense receive’ is applied to the simulation of crossing-beam and its compensation. The results of simulations demonstrate the validity of the method combining pre-process and FrFT to compensate ‘three crossing’.
2014, 43(1): 42-48.
doi: 10.3969/j.issn.1001-0548.2014.01.007
Abstract:
Aimed at the shortage of similar region capture and directional information obtainment for SAR image despeckling using conventional non-local means method (NLM), a new NLM SAR image despeckling method is proposed based on multiple different directional anisotropic Gaussian directional window and Stein unbiased risk estimation (SURE) aggregation. The ratio measurement strategy is utilized to compute the similarity of two patches and the NLM result is computed based on the anisotropic Gaussian windows with some direction. The results of NLM with different anisotropic Gaussian windows are aggregated by using the Stein unbiased risk estimation criterion to obtain the final SAR despeckling result. For multiple SAR images, the experiment results show that the new method has advantages in the SAR image despeckling performance, and can well preserve the local geometric structure information, which is essential for understanding and interpretation of SAR image.
Aimed at the shortage of similar region capture and directional information obtainment for SAR image despeckling using conventional non-local means method (NLM), a new NLM SAR image despeckling method is proposed based on multiple different directional anisotropic Gaussian directional window and Stein unbiased risk estimation (SURE) aggregation. The ratio measurement strategy is utilized to compute the similarity of two patches and the NLM result is computed based on the anisotropic Gaussian windows with some direction. The results of NLM with different anisotropic Gaussian windows are aggregated by using the Stein unbiased risk estimation criterion to obtain the final SAR despeckling result. For multiple SAR images, the experiment results show that the new method has advantages in the SAR image despeckling performance, and can well preserve the local geometric structure information, which is essential for understanding and interpretation of SAR image.
2014, 43(1): 49-53,154.
doi: 10.3969/j.issn.1001-0548.2014.01.008
Abstract:
In recent years, the research of compact polarimetric (CP) modes has caught attention . By using the full polarimetric (FP) mode, the existence of orientation angle (OA) induced by terrain slope will lead to the difficulty in post-processing, such as terrain targets classification and identification. In the paper, the OA estimation is derived and analyzed by using the scattering vectors of CP SAR modes. Recurring to the circular polarimetry, the OA can be evaluated from the CP SAR data. And the experimental results based on measured data sets have been shown to improve the estimation methods, while analyzing the practicability of the estimation under CP modes and its value in engineering application.
In recent years, the research of compact polarimetric (CP) modes has caught attention . By using the full polarimetric (FP) mode, the existence of orientation angle (OA) induced by terrain slope will lead to the difficulty in post-processing, such as terrain targets classification and identification. In the paper, the OA estimation is derived and analyzed by using the scattering vectors of CP SAR modes. Recurring to the circular polarimetry, the OA can be evaluated from the CP SAR data. And the experimental results based on measured data sets have been shown to improve the estimation methods, while analyzing the practicability of the estimation under CP modes and its value in engineering application.
2014, 43(1): 54-59.
doi: 10.3969/j.issn.1001-0548.2014.01.009
Abstract:
The load resistance changes may cause the variation of operational frequency of the inductively coupled power transfer (ICPT) systems, leading to the reduction of power transfer efficiency and system instability. An improved fuzzy control strategy is designed to ensure the stability of the resonant operational frequency when the load changes by controlling the effective value of the primary resonant capacitor array. This method promotes the power transfer efficiency and stability of ICPT systems. The experimental results verify the functionality and superiority of the proposed strategy.
The load resistance changes may cause the variation of operational frequency of the inductively coupled power transfer (ICPT) systems, leading to the reduction of power transfer efficiency and system instability. An improved fuzzy control strategy is designed to ensure the stability of the resonant operational frequency when the load changes by controlling the effective value of the primary resonant capacitor array. This method promotes the power transfer efficiency and stability of ICPT systems. The experimental results verify the functionality and superiority of the proposed strategy.
2014, 43(1): 60-65.
doi: 10.3969/j.issn.1001-0548.2014.01.010
Abstract:
This paper proposes a novel method for view-invariant 3D hand trajectory-based recognition. The image depth information in gesture segmentation is collected by using Kinect sensor. View-invariant 3D hand trajectory is represented by improving centroid distance function. Hidden Markov model is applied to train and recognize hand gesture. Experiment results show that the proposed method is robust under the condition of different illumination and complex background. The illustrated system can successfully recognize spotted hand gestures with a 97.7% recognition rate for Arabic numbers 0 to 9.
This paper proposes a novel method for view-invariant 3D hand trajectory-based recognition. The image depth information in gesture segmentation is collected by using Kinect sensor. View-invariant 3D hand trajectory is represented by improving centroid distance function. Hidden Markov model is applied to train and recognize hand gesture. Experiment results show that the proposed method is robust under the condition of different illumination and complex background. The illustrated system can successfully recognize spotted hand gestures with a 97.7% recognition rate for Arabic numbers 0 to 9.
2014, 43(1): 66-70.
doi: 10.3969/j.issn.1001-0548.2014.01.011
Abstract:
Based on the Pareto optimal conception,an Improved nondominated sorting genetic algorithm II (NSGA-II) seeking non-inferior solution set of multi-objective optimization (MO) problems is proposed, while the heuristic crossover operator based on nearest-neighborhood, the improved mutation operator and the filtering of non-inferior solutions are focused and discussed. The algorithm proposed is applied to a two-objective optimization of scheduling of arrival aircrafts at an airport with multiple runways, where both the sum of all the delays squared and the fuel cost of all the aircrafts were required to be minimized. After the simulation experiment, the optimal solutions are analyzed and compared with the best solutions founded by some existing algorithms. The research result demonstrates that improved NSGA-II possesses a good application foreground for multi-objective optimization of scheduling arrival aircrafts at an airport with multiple runways.
Based on the Pareto optimal conception,an Improved nondominated sorting genetic algorithm II (NSGA-II) seeking non-inferior solution set of multi-objective optimization (MO) problems is proposed, while the heuristic crossover operator based on nearest-neighborhood, the improved mutation operator and the filtering of non-inferior solutions are focused and discussed. The algorithm proposed is applied to a two-objective optimization of scheduling of arrival aircrafts at an airport with multiple runways, where both the sum of all the delays squared and the fuel cost of all the aircrafts were required to be minimized. After the simulation experiment, the optimal solutions are analyzed and compared with the best solutions founded by some existing algorithms. The research result demonstrates that improved NSGA-II possesses a good application foreground for multi-objective optimization of scheduling arrival aircrafts at an airport with multiple runways.
2014, 43(1): 71-75.
doi: 10.3969/j.issn.1001-0548.2014.01.012
Abstract:
The paper considers the controller design problem of disturbance rejection for nonlinear systems under external persistent disturbance by using the full-state linearization approach. The disturbance rejection controller with nonlinear term is designed, in which the nonlinear control term cancels the open-loop nonlinearity. According to the internal-model principle, the internal-model compensator is constructed which has the same dynamical characteristic with disturbance. The optimal regulator of the augmented system is designed by using Pontryagin minimum principle. Then the nonlinear disturbance rejection controller based on internal model is obtained, in which the internal-model compensation control term cancels the effect produced by disturbance. Comparing with the nonlinear feedforward and feedback disturbance rejection controller, the designed nonlinear internal-model-based disturbance rejection controller can eliminate eliminating the nonlinearity and rejecting disturbance with zero steady-state error.
The paper considers the controller design problem of disturbance rejection for nonlinear systems under external persistent disturbance by using the full-state linearization approach. The disturbance rejection controller with nonlinear term is designed, in which the nonlinear control term cancels the open-loop nonlinearity. According to the internal-model principle, the internal-model compensator is constructed which has the same dynamical characteristic with disturbance. The optimal regulator of the augmented system is designed by using Pontryagin minimum principle. Then the nonlinear disturbance rejection controller based on internal model is obtained, in which the internal-model compensation control term cancels the effect produced by disturbance. Comparing with the nonlinear feedforward and feedback disturbance rejection controller, the designed nonlinear internal-model-based disturbance rejection controller can eliminate eliminating the nonlinearity and rejecting disturbance with zero steady-state error.
2014, 43(1): 76-81.
doi: 10.3969/j.issn.1001-0548.2014.01.013
Abstract:
Because of the simplicity of the implementation, various attacking forms, destructivity, and difficulty of filtering out, DoS has become one of the most serious security threats to the Internet. In this paper, we propose an improved transductive confidence machines for k-nearest neighbors (ITCM-KNN) algorithm and establish a framework for DoS detection. Evaluation and experiments of the algorithm are based on the standard dataset KDD Cup 1999 with 5 selected features using the information gain algorithm, which can ensure high detection rate while reducing the dimension of the features. The proposed algorithm does not need learning and modeling attacks. It only needs a small number of samples as training data set. The comparison results show that the true positive rate (TP) of the improved TCM-KNN algorithm is about 99.99%, which is higher than other detection algorithm such as SVM.
Because of the simplicity of the implementation, various attacking forms, destructivity, and difficulty of filtering out, DoS has become one of the most serious security threats to the Internet. In this paper, we propose an improved transductive confidence machines for k-nearest neighbors (ITCM-KNN) algorithm and establish a framework for DoS detection. Evaluation and experiments of the algorithm are based on the standard dataset KDD Cup 1999 with 5 selected features using the information gain algorithm, which can ensure high detection rate while reducing the dimension of the features. The proposed algorithm does not need learning and modeling attacks. It only needs a small number of samples as training data set. The comparison results show that the true positive rate (TP) of the improved TCM-KNN algorithm is about 99.99%, which is higher than other detection algorithm such as SVM.
2014, 43(1): 82-87.
doi: 10.3969/j.issn.1001-0548.2014.01.014
Abstract:
How to apply wireless sensor network to monitor the water environment has become an important subject. Based on the theory of square grid partition, this paper proposes a routing algorithm with the yardstick of entropy to evaluate the stability of route in the dynamic water environment. In this algorithm, the information collecting area is subdivided by means of cube grid, the shortest route to sink node in the grid is searched, and the router is chosen by means of entropy to reduce the number of reconstructing routers or repairing routers and possibly provide QoS guarantee in the environment in which network topology ration changes frequently. The stimulated experiment and performance analysis prove that EWSQoS algorithm takes more advantage than Long-term, DBR, and DTN algorithms in the fields of the number of reconstructing routers, success rates of routers, energy consumption of network, and network latency.
How to apply wireless sensor network to monitor the water environment has become an important subject. Based on the theory of square grid partition, this paper proposes a routing algorithm with the yardstick of entropy to evaluate the stability of route in the dynamic water environment. In this algorithm, the information collecting area is subdivided by means of cube grid, the shortest route to sink node in the grid is searched, and the router is chosen by means of entropy to reduce the number of reconstructing routers or repairing routers and possibly provide QoS guarantee in the environment in which network topology ration changes frequently. The stimulated experiment and performance analysis prove that EWSQoS algorithm takes more advantage than Long-term, DBR, and DTN algorithms in the fields of the number of reconstructing routers, success rates of routers, energy consumption of network, and network latency.
2014, 43(1): 88-94.
doi: 10.3969/j.issn.1001-0548.2014.01.015
Abstract:
Near field communication (NFC) stack is a kind of middleware. Its main task is to implement the function defined by NFC Forum's specifications and protocols and to construct different service models according to the business scenario and NFC operating mode. The present NFC stack can hardly not only meet the requirement of simultaneously support of different types of operation systems and different types of NFC controllers, but also keep compatible to the third party NFC applications. So this paper proposes a cross platform NFC stack architecture. In this architecture, NFC stack can adapt to different operation systems and different NFC controllers. It can also work with different operation system service components or different application frameworks, and third party NFC applications can be supported perfectly.
Near field communication (NFC) stack is a kind of middleware. Its main task is to implement the function defined by NFC Forum's specifications and protocols and to construct different service models according to the business scenario and NFC operating mode. The present NFC stack can hardly not only meet the requirement of simultaneously support of different types of operation systems and different types of NFC controllers, but also keep compatible to the third party NFC applications. So this paper proposes a cross platform NFC stack architecture. In this architecture, NFC stack can adapt to different operation systems and different NFC controllers. It can also work with different operation system service components or different application frameworks, and third party NFC applications can be supported perfectly.
2014, 43(1): 95-100.
doi: 10.3969/j.issn.1001-0548.2014.01.016
Abstract:
Virtualization and scalability & programmability are two key characteristics to be supported by network devices for the development of Internet. In recent years, researchers have proposed many prototypes based on these two requirements. The virtual router is one representative prototype, which realizes these two requirements by the virtualization technique and scalable routing software. However, due to the overhead of virtualization techniques, the forwarding performance of a virtual router is usually limited. This paper investigates different virtualization techniques and scalable routing software, establishes the test-bed and evaluates the forwarding performance under different virtualization techniques, and conducts the assessment on several typical virtual I/O acceleration techniques.
Virtualization and scalability & programmability are two key characteristics to be supported by network devices for the development of Internet. In recent years, researchers have proposed many prototypes based on these two requirements. The virtual router is one representative prototype, which realizes these two requirements by the virtualization technique and scalable routing software. However, due to the overhead of virtualization techniques, the forwarding performance of a virtual router is usually limited. This paper investigates different virtualization techniques and scalable routing software, establishes the test-bed and evaluates the forwarding performance under different virtualization techniques, and conducts the assessment on several typical virtual I/O acceleration techniques.
2014, 43(1): 101-106.
doi: 10.3969/j.issn.1001-0548.2014.01.017
Abstract:
The security problems of software become more and more serious,and software survivability is an extension of software security researches. However, the survivability models can rarely bring out a practical method by now. In this paper, we consider the effect of different system structures and runtime environments on system survivability. Firstly, we construct a service survivability model by considering the effect of environment; secondly, we consider the relationship between the system structure and services and construct a model based on service survivability to reflect the system survivability. Finally, based on this model, a recovery approach is illustrated when parts of or all the system's services are failed.
The security problems of software become more and more serious,and software survivability is an extension of software security researches. However, the survivability models can rarely bring out a practical method by now. In this paper, we consider the effect of different system structures and runtime environments on system survivability. Firstly, we construct a service survivability model by considering the effect of environment; secondly, we consider the relationship between the system structure and services and construct a model based on service survivability to reflect the system survivability. Finally, based on this model, a recovery approach is illustrated when parts of or all the system's services are failed.
2014, 43(1): 107-112.
doi: 10.3969/j.issn.1001-0548.2014.01.018
Abstract:
To separate the business rules from corresponding processes in the traditional enterpriseservice- bus (ESB) based applications could lead to the lower maintenance cost. However, with the increasing business complexities, the correctness of rule-based service composition is often hard to be verified. This paper presents a novel model checking approach to verify the correctness of rule-based message routing in ESB integrated with rule engine. First, the message routing rules are converted into the six-tuple service model which is then transformed into the input program of NuSMV. The automatic verification is finally achieved with the help of NuSMV. The example demonstrates how to verify the correctness of rule-based message routing of loan approval service and proves the feasibility of this approach.
To separate the business rules from corresponding processes in the traditional enterpriseservice- bus (ESB) based applications could lead to the lower maintenance cost. However, with the increasing business complexities, the correctness of rule-based service composition is often hard to be verified. This paper presents a novel model checking approach to verify the correctness of rule-based message routing in ESB integrated with rule engine. First, the message routing rules are converted into the six-tuple service model which is then transformed into the input program of NuSMV. The automatic verification is finally achieved with the help of NuSMV. The example demonstrates how to verify the correctness of rule-based message routing of loan approval service and proves the feasibility of this approach.
2014, 43(1): 113-118.
doi: 10.3969/j.issn.1001-0548.2014.01.019
Abstract:
To solve the bottle-neck problem of lower efficiency existed in radar echo generation and signal processing with serial simulation architecture, a multi-data links computing model based on multi-core memory-shared platform is proposed. This method could greatly promote simulation efficiency by taking advantage of multi-core. According to the independent characteristic between radar tasks in the same scheduling interval, the model takes data division, task allocation, time synchronization, and load monitoring with measurement into account to discuss its parallel characteristic. The Pentium(R) Dual-Core E5200 CPU with 2 GB memory is used to test the target scene with 20 batches. Simulation results demonstrate that, compared with serial simulation, the data frame average processing time of parallel model decreases 37.5% and the data frame processing speedup ratio curve has good acceleration performance. This parallel algorithm can reduce the simulation time greatly.
To solve the bottle-neck problem of lower efficiency existed in radar echo generation and signal processing with serial simulation architecture, a multi-data links computing model based on multi-core memory-shared platform is proposed. This method could greatly promote simulation efficiency by taking advantage of multi-core. According to the independent characteristic between radar tasks in the same scheduling interval, the model takes data division, task allocation, time synchronization, and load monitoring with measurement into account to discuss its parallel characteristic. The Pentium(R) Dual-Core E5200 CPU with 2 GB memory is used to test the target scene with 20 batches. Simulation results demonstrate that, compared with serial simulation, the data frame average processing time of parallel model decreases 37.5% and the data frame processing speedup ratio curve has good acceleration performance. This parallel algorithm can reduce the simulation time greatly.
2014, 43(1): 119-124.
doi: 10.3969/j.issn.1001-0548.2014.01.020
Abstract:
An I/O_WF_Net model based on Petri nets is proposed in this paper. In the I/O_WF_Net model, the activities of a workflow are abstracted as transitions and the inputs and outputs of an activity are abstracted as places of a Petri net, so the model is convenient for test cases generating. The modeling method of the components and structures of a workflow are described, an algorithm that transforms a workflow net constrained by inputs and outputs into the I/O_WF_Net model and the corresponding simplifying method are given.
An I/O_WF_Net model based on Petri nets is proposed in this paper. In the I/O_WF_Net model, the activities of a workflow are abstracted as transitions and the inputs and outputs of an activity are abstracted as places of a Petri net, so the model is convenient for test cases generating. The modeling method of the components and structures of a workflow are described, an algorithm that transforms a workflow net constrained by inputs and outputs into the I/O_WF_Net model and the corresponding simplifying method are given.
2014, 43(1): 125-130.
doi: 10.3969/j.issn.1001-0548.2014.01.021
Abstract:
A simulation risk analysis method based on influence nets is proposed for simulation risk quantitative analysis. The simulation risk description is improved for considering variety impact of simulation failure. The influence nets model of simulation risk analysis is established by taking failure modes, decision effect and impact levels as influence nets nodes. A method for determining influence nets parameters is designed to make the quantitative description of failure mode and causal relationship to be reality. An algorithm to calculate the causal strength is given. The semi-quantitative express of simulation risk analysis is carried out by introducing two-tuple linguistic to mass the analysis results. Finally, an example is given to prove the validity and feasibility of this method.
A simulation risk analysis method based on influence nets is proposed for simulation risk quantitative analysis. The simulation risk description is improved for considering variety impact of simulation failure. The influence nets model of simulation risk analysis is established by taking failure modes, decision effect and impact levels as influence nets nodes. A method for determining influence nets parameters is designed to make the quantitative description of failure mode and causal relationship to be reality. An algorithm to calculate the causal strength is given. The semi-quantitative express of simulation risk analysis is carried out by introducing two-tuple linguistic to mass the analysis results. Finally, an example is given to prove the validity and feasibility of this method.
2014, 43(1): 131-136.
doi: 10.3969/j.issn.1001-0548.2014.01.022
Abstract:
Support vector ordinal regression (SVOR) has been proven to be the promising algorithm for solving ordinal regression problems. However, its performance tends to be strongly affected by outliers in the training datasets. To remedy this drawback, a truncated loss smooth SVOR (TLS-SVOR) is proposed. While learning ordinal regression models, the loss s of the misranked sample is bounded between 0 and the truncated coefficient u. First, a piecewise polynomial function with parameter u is approximated to s. Then, by applying the strategy of smooth support vector machine for classification, the optimization problem is replaced with an unconstrained function which is twice continuously differentiable. The algorithm employs Newton's method to obtain the unique discriminant hyperplane. The optimal parameter combination of TLS-SVOR is determined by a two-stage uniform designed model selection methodology. The experimental results on benchmark datasets show that TLS-SVOR has advantage in terms of accuracy over other ordinal regression approaches.
Support vector ordinal regression (SVOR) has been proven to be the promising algorithm for solving ordinal regression problems. However, its performance tends to be strongly affected by outliers in the training datasets. To remedy this drawback, a truncated loss smooth SVOR (TLS-SVOR) is proposed. While learning ordinal regression models, the loss s of the misranked sample is bounded between 0 and the truncated coefficient u. First, a piecewise polynomial function with parameter u is approximated to s. Then, by applying the strategy of smooth support vector machine for classification, the optimization problem is replaced with an unconstrained function which is twice continuously differentiable. The algorithm employs Newton's method to obtain the unique discriminant hyperplane. The optimal parameter combination of TLS-SVOR is determined by a two-stage uniform designed model selection methodology. The experimental results on benchmark datasets show that TLS-SVOR has advantage in terms of accuracy over other ordinal regression approaches.
2014, 43(1): 137-143.
doi: 10.3969/j.issn.1001-0548.2014.01.023
Abstract:
Case-based reasoning (CBR) which stores old problems and solution information as cases can solve new problems of the particle swarm optimization (PSO) with its long-term memory during the learning phase for multiple robots in an unknown environment. The PSO components which offer trainings to the robot in specially-designed simulation environments to deliver basic behaviors enhance their robustness and adaptivity. The CBR components which selects solution from the case base evolved for basic behaviors rank them according to their performance in the new complex enviroment and introduce them to a PSO algorithm's initial population, hence speeding up the learning process. Behavior-based multi-robot formation control task is employed as a platform to assess the effectiveness of this approach with robot simulation software MissionLab. Simulation and experimental results show that the CBR-injected PSO algorithm can quickly obtain optimal control parameters and multi-robot formation performs better in unknown environment.
Case-based reasoning (CBR) which stores old problems and solution information as cases can solve new problems of the particle swarm optimization (PSO) with its long-term memory during the learning phase for multiple robots in an unknown environment. The PSO components which offer trainings to the robot in specially-designed simulation environments to deliver basic behaviors enhance their robustness and adaptivity. The CBR components which selects solution from the case base evolved for basic behaviors rank them according to their performance in the new complex enviroment and introduce them to a PSO algorithm's initial population, hence speeding up the learning process. Behavior-based multi-robot formation control task is employed as a platform to assess the effectiveness of this approach with robot simulation software MissionLab. Simulation and experimental results show that the CBR-injected PSO algorithm can quickly obtain optimal control parameters and multi-robot formation performs better in unknown environment.
2014, 43(1): 144-148.
doi: 10.3969/j.issn.1001-0548.2014.01.024
Abstract:
An authorization method and a simple key agreement protocol based on both sides' IDs of participants are proposed to meet the requirements for secure storage and secure access of smart TV payment. Combined with symmetric encryption algorithms, the data transmission and data access protections between smart TV and security storage chip are realized and the scale and complexion of the security storage chip are reduced also. The result shows that the chip gate complexity has been reduced to about 1/6 of ECC and 1/4 of RSA with the same encryption strength.
An authorization method and a simple key agreement protocol based on both sides' IDs of participants are proposed to meet the requirements for secure storage and secure access of smart TV payment. Combined with symmetric encryption algorithms, the data transmission and data access protections between smart TV and security storage chip are realized and the scale and complexion of the security storage chip are reduced also. The result shows that the chip gate complexity has been reduced to about 1/6 of ECC and 1/4 of RSA with the same encryption strength.
2014, 43(1): 149-154.
doi: 10.3969/j.issn.1001-0548.2014.01.025
Abstract:
Atmospheric limb radiation model in UV band was established based on transport theory, and spherical atmospheric accumulation solution method is proposed. According to Snell's law of refraction and spherical trigonometry formula, the calculation method of refractive path in limb geometry is presented. The calculation results of limb transmittance and limb radiance in typical atmospheric modes and tangent heights are given, and the impact of refractive effect is analyzed. The calculation results can provide a reference for space borne optical detection system in simulation and application and the study of global environmental change and climate prediction.
Atmospheric limb radiation model in UV band was established based on transport theory, and spherical atmospheric accumulation solution method is proposed. According to Snell's law of refraction and spherical trigonometry formula, the calculation method of refractive path in limb geometry is presented. The calculation results of limb transmittance and limb radiance in typical atmospheric modes and tangent heights are given, and the impact of refractive effect is analyzed. The calculation results can provide a reference for space borne optical detection system in simulation and application and the study of global environmental change and climate prediction.
2014, 43(1): 155-160.
doi: 10.3969/j.issn.1001-0548.2014.01.026
Abstract:
This paper proposed a precise numerical method to calculate the point spread function (PSF) when optical systems encounter micro-vibration within a certain amount of exposure time. Conventional methods evaluate the modulation transfer function (MTF) degradation by using the image point displacement caused by micro-vibration. They ignore the change of MTF while the vibration is happening, which may cause errors if the amplitude of the vibration is large. The proposed method eliminates this error by integrating PSFs at each moment during the vibration. This method is well suited for computing the PSF of the spatial light propagating through an unstable optical system.
This paper proposed a precise numerical method to calculate the point spread function (PSF) when optical systems encounter micro-vibration within a certain amount of exposure time. Conventional methods evaluate the modulation transfer function (MTF) degradation by using the image point displacement caused by micro-vibration. They ignore the change of MTF while the vibration is happening, which may cause errors if the amplitude of the vibration is large. The proposed method eliminates this error by integrating PSFs at each moment during the vibration. This method is well suited for computing the PSF of the spatial light propagating through an unstable optical system.
