Volume 16,Issue 1,2005 Table of Contents
2005, 16(1):1-7.
Abstract:
The paper gives some thinking according to the following four aspects: 1) from the law of things development, revealing the development history of software engineering technology; 2) from the point of software natural characteristic, analyzing the construction of every abstraction layer of virtual machine; 3) from the point of software development, proposing the research content of software engineering discipline, and research the pattern of industrialized software production; 4) based on the appearance of Internet technology, exploring the development trend of software technology.
The paper gives some thinking according to the following four aspects: 1) from the law of things development, revealing the development history of software engineering technology; 2) from the point of software natural characteristic, analyzing the construction of every abstraction layer of virtual machine; 3) from the point of software development, proposing the research content of software engineering discipline, and research the pattern of industrialized software production; 4) based on the appearance of Internet technology, exploring the development trend of software technology.
2 A Description Approach to Software by HOQ Extension Concept and Its Quantitative Structuralization
2005, 16(1):8-16.
Abstract:
In order to improve the quality and productivity of software, the software structure which is deeply related to them, is observed in this paper. Firstly, the problems of software structure analysis and design of current methods are examined. Then, the HOQ (house of quality) concept of the QFD (quality function deployment) is extended as a tool for software description based on the similarity between HOQ in quality design and engineering drawing in product design. By applying Simon's idea of system's near decomposability, the quantitative structuralization method is proposed based on the QMT3 (quantification method of type 3). Furthermore, the features of this method are clarified by comparison with the current methods. Finally, the effectiveness of the method for software structure analysis and design is verified by an application. Therefore, the method can help successfully for assurance of software quality.
In order to improve the quality and productivity of software, the software structure which is deeply related to them, is observed in this paper. Firstly, the problems of software structure analysis and design of current methods are examined. Then, the HOQ (house of quality) concept of the QFD (quality function deployment) is extended as a tool for software description based on the similarity between HOQ in quality design and engineering drawing in product design. By applying Simon's idea of system's near decomposability, the quantitative structuralization method is proposed based on the QMT3 (quantification method of type 3). Furthermore, the features of this method are clarified by comparison with the current methods. Finally, the effectiveness of the method for software structure analysis and design is verified by an application. Therefore, the method can help successfully for assurance of software quality.
2005, 16(1):17-28.
Abstract:
Software engineers always find the state of some defects can influence the detecting rate of other defects. These defects are correlated defects. This paper gives the definition of correlated software defects, gets some property of correlated defects by experiment, and then proposes an approach named testing approach with defects replacement, to detect correlated defects. It also analyzes the capability and efficiency of the approach by experiment. The data show that the approach is efficient to detect correlated software defects.
Software engineers always find the state of some defects can influence the detecting rate of other defects. These defects are correlated defects. This paper gives the definition of correlated software defects, gets some property of correlated defects by experiment, and then proposes an approach named testing approach with defects replacement, to detect correlated defects. It also analyzes the capability and efficiency of the approach by experiment. The data show that the approach is efficient to detect correlated software defects.
2005, 16(1):29-36.
Abstract:
Handheld mobile computing has increasingly become a mainstream computing paradigm, in which human-computer interaction is an essential issue. Multi-Modal user interface and multi-modal interaction can effectively improve the interaction efficiency in mobile computing. This paper presents a multi-modal interaction model and discusses the application of multi-modal interaction in handheld devices. Then the tour guide system is described. An experimental evaluation shows that the multi-modal interaction, based on pen and speech, can greatly improve its interaction.
Handheld mobile computing has increasingly become a mainstream computing paradigm, in which human-computer interaction is an essential issue. Multi-Modal user interface and multi-modal interaction can effectively improve the interaction efficiency in mobile computing. This paper presents a multi-modal interaction model and discusses the application of multi-modal interaction in handheld devices. Then the tour guide system is described. An experimental evaluation shows that the multi-modal interaction, based on pen and speech, can greatly improve its interaction.
2005, 16(1):37-49.
Abstract:
To accommodate the frequent changes of user requirements and operating environments, software systems have to be much more flexible. Fortunately, modeling variability is just a realistic and efficient approach to controlling variability and implementing software reuse, which does well not only in identifying and expressing variability, but also in assisting the management of variability evolution. This paper proposes an approach to modeling variability in product family. In this approach, variabilities of system behaviors are modeled through extended use case models, while variabilities in functionality and quality are captured by feature models, and above all, both the models adopt consistent mechanisms to model variability. Summarily, the whole modeling process of the approach is discussed systematically through a real software family on mobile phone.
To accommodate the frequent changes of user requirements and operating environments, software systems have to be much more flexible. Fortunately, modeling variability is just a realistic and efficient approach to controlling variability and implementing software reuse, which does well not only in identifying and expressing variability, but also in assisting the management of variability evolution. This paper proposes an approach to modeling variability in product family. In this approach, variabilities of system behaviors are modeled through extended use case models, while variabilities in functionality and quality are captured by feature models, and above all, both the models adopt consistent mechanisms to model variability. Summarily, the whole modeling process of the approach is discussed systematically through a real software family on mobile phone.
2005, 16(1):50-57.
Abstract:
Pen-Based user interface (Pen UI) is a primary style in Post-WIMP world. Two kinds of participants including the HCI designers and the user designers are involved in the development cycle of Pen UI. It is crucial to catch users intention and accomplish the linkage between presentation and control of interaction information. According to the two dimensions, OICM (orthogonal interaction information architecture coordinate model) is developed. This model is described from four quadrants including problem domain knowledge, task information, rule collection, and context linkage. The main ideas and features of OICM are declared in detail, especially the implementation method based on XML technique. Eventually, a component-oriented UI platform built on this model and some relevant systems are introduced.
Pen-Based user interface (Pen UI) is a primary style in Post-WIMP world. Two kinds of participants including the HCI designers and the user designers are involved in the development cycle of Pen UI. It is crucial to catch users intention and accomplish the linkage between presentation and control of interaction information. According to the two dimensions, OICM (orthogonal interaction information architecture coordinate model) is developed. This model is described from four quadrants including problem domain knowledge, task information, rule collection, and context linkage. The main ideas and features of OICM are declared in detail, especially the implementation method based on XML technique. Eventually, a component-oriented UI platform built on this model and some relevant systems are introduced.
2005, 16(1):58-66.
Abstract:
Jacquard image segmentation is the linchpin of jacquard pattern design. Curve evolution model is a popular method for image segmentation. However, it cannot detect image features in the presence of noise. The Mumford-Shah model is more robust than curve evolution model to detect discontinuities under noisy environment, so it is more suitable for segmentation of noisy jacquard images. In this paper, an algorithm is presented to implement the numerical solving of the Mumford-Shah model, which combines the merits of finite element method and quasi-Newton method. First, a discrete version of the model is defined on finite element spaces over adaptive triangulation. Then an adjustment scheme for the triangulation is enforced to improve the iteration efficiency before current iteration begins. Finally, a minimization method based on quasi-Newton algorithm is applied to find the absolute minimum of the discrete model in the sense of Gamma-convergence. The proposed algorithm works well when it is applied to segment noisy jacquard images.
Jacquard image segmentation is the linchpin of jacquard pattern design. Curve evolution model is a popular method for image segmentation. However, it cannot detect image features in the presence of noise. The Mumford-Shah model is more robust than curve evolution model to detect discontinuities under noisy environment, so it is more suitable for segmentation of noisy jacquard images. In this paper, an algorithm is presented to implement the numerical solving of the Mumford-Shah model, which combines the merits of finite element method and quasi-Newton method. First, a discrete version of the model is defined on finite element spaces over adaptive triangulation. Then an adjustment scheme for the triangulation is enforced to improve the iteration efficiency before current iteration begins. Finally, a minimization method based on quasi-Newton algorithm is applied to find the absolute minimum of the discrete model in the sense of Gamma-convergence. The proposed algorithm works well when it is applied to segment noisy jacquard images.
2005, 16(1):67-76.
Abstract:
In this paper, a modification to the fuzzy connectedness image segmentation is presented. Through checking the property affinity between the seed pixel and the pixel along the optimal path which has the largest fuzzy connectedness from the pixel to seed pixel, good results can be achieved, especially for those objects with blurred boundary. Additionally, an image-scanning mechanism algorithm for detecting optimal paths is proposed to calculate the fuzzy connectedness between pixels and the seed pixel one by one. This algorithm can make full use of the properties of fuzzy connectedness and property affinity, and detect the optimal path between two pixels effectively. Experimental examples show that the new method is simple, fast, and works well for some images.
In this paper, a modification to the fuzzy connectedness image segmentation is presented. Through checking the property affinity between the seed pixel and the pixel along the optimal path which has the largest fuzzy connectedness from the pixel to seed pixel, good results can be achieved, especially for those objects with blurred boundary. Additionally, an image-scanning mechanism algorithm for detecting optimal paths is proposed to calculate the fuzzy connectedness between pixels and the seed pixel one by one. This algorithm can make full use of the properties of fuzzy connectedness and property affinity, and detect the optimal path between two pixels effectively. Experimental examples show that the new method is simple, fast, and works well for some images.
2005, 16(1):77-88.
Abstract:
ROI (region of interest) plays an important role in medical image analysis. In this paper, an efficient approach to ROI extraction based on monotonically marching curve evolution is proposed. The improvement is in two aspects: first, a new monotonically marching snake integrating ROI information is presented by minimizing the new defined ROI energy. Due to the region based speed term, the front could even propagate in low contrast and narrow thin areas. Second, a multi-initial fast marching algorithm is developed for numerical implementation, where a multi-initial scheme can perform the selective growth of the front, thus further reduce the front leaking. Furthermore, a multiscale scheme for numerical implementation is adopted, where a fast passing solution method is used for determining the initial solution on the finer scale that greatly reduces the computational cost. The validity of the proposed approach is demonstrated on the medical image ROI extraction. Experimental results show that the approach is efficient both in computational cost and segmentation quality. Low contrast and narrow thin ROI could be efficiently extracted precisely by the approach.
ROI (region of interest) plays an important role in medical image analysis. In this paper, an efficient approach to ROI extraction based on monotonically marching curve evolution is proposed. The improvement is in two aspects: first, a new monotonically marching snake integrating ROI information is presented by minimizing the new defined ROI energy. Due to the region based speed term, the front could even propagate in low contrast and narrow thin areas. Second, a multi-initial fast marching algorithm is developed for numerical implementation, where a multi-initial scheme can perform the selective growth of the front, thus further reduce the front leaking. Furthermore, a multiscale scheme for numerical implementation is adopted, where a fast passing solution method is used for determining the initial solution on the finer scale that greatly reduces the computational cost. The validity of the proposed approach is demonstrated on the medical image ROI extraction. Experimental results show that the approach is efficient both in computational cost and segmentation quality. Low contrast and narrow thin ROI could be efficiently extracted precisely by the approach.
2005, 16(1):89-100.
Abstract:
One of the key issues in real-time theory is the schedulable analysis of a given task set with fixed priority. All the proposed schedulability test methods can be classified into two types: polynomial time methods and exact methods. Polynomial time methods use a sufficient schedulability condition, and several least upper bounds of the processor utilization under ideal assumptions have been developed. Exact methods based on the necessary and sufficient schedulability condition guarantee that the test result for every task set is correct. However, the pseudo-polynomial complexity of the exact tests is too complex to be executed online for large task sets. This paper presents a novel ISTA (improved schedulability test algorithm) for analyzing the schedulability of periodic task sets under Rate Monotonic priority assignment. A pruning theorem for the Task_i space is derived, the schedulability correlation among tasks and its effect on the schedulability test are investigated, and the related theorems are proven. Based on the above results, a new improved pseudo-polynomial schedulability test algorithm is developed, and several comparative simulation experiments among the three methods are conducted. Extensive simulations show that the average schedulability test performance as a function of number of the tasks can be significantly improved.
One of the key issues in real-time theory is the schedulable analysis of a given task set with fixed priority. All the proposed schedulability test methods can be classified into two types: polynomial time methods and exact methods. Polynomial time methods use a sufficient schedulability condition, and several least upper bounds of the processor utilization under ideal assumptions have been developed. Exact methods based on the necessary and sufficient schedulability condition guarantee that the test result for every task set is correct. However, the pseudo-polynomial complexity of the exact tests is too complex to be executed online for large task sets. This paper presents a novel ISTA (improved schedulability test algorithm) for analyzing the schedulability of periodic task sets under Rate Monotonic priority assignment. A pruning theorem for the Task_i space is derived, the schedulability correlation among tasks and its effect on the schedulability test are investigated, and the related theorems are proven. Based on the above results, a new improved pseudo-polynomial schedulability test algorithm is developed, and several comparative simulation experiments among the three methods are conducted. Extensive simulations show that the average schedulability test performance as a function of number of the tasks can be significantly improved.
2005, 16(1):101-107.
Abstract:
A hard real-time system is usually subject to stringent reliability and timing constraints due to the fact that failure to produce correct results in a timely manner may lead to a disaster. Almost all fault-tolerant scheduling algorithms so far are designed to deal with hardware faults, less of those take possible software faults into account. This paper presents two software fault-tolerant real-time scheduling algorithms that are similar to EDF (earliest deadline first), called PKSA (probing K-step algorithm) and CUBA (changing utilization-based algorithm). The most important contribution of the algorithms is the probing of certain steps during the execution of tasks in order to prevent early failures in execution from triggering failures in the subsequent job executions. Therefore, the algorithms increase the successful percentage of task抯 completion, and meanwhile decrease the wasted CPU time slots. The simulation experiments show that the algorithms have much better trade-offs between scheduling costs and performance than the well-known algorithms so far.
A hard real-time system is usually subject to stringent reliability and timing constraints due to the fact that failure to produce correct results in a timely manner may lead to a disaster. Almost all fault-tolerant scheduling algorithms so far are designed to deal with hardware faults, less of those take possible software faults into account. This paper presents two software fault-tolerant real-time scheduling algorithms that are similar to EDF (earliest deadline first), called PKSA (probing K-step algorithm) and CUBA (changing utilization-based algorithm). The most important contribution of the algorithms is the probing of certain steps during the execution of tasks in order to prevent early failures in execution from triggering failures in the subsequent job executions. Therefore, the algorithms increase the successful percentage of task抯 completion, and meanwhile decrease the wasted CPU time slots. The simulation experiments show that the algorithms have much better trade-offs between scheduling costs and performance than the well-known algorithms so far.
2005, 16(1):108-115.
Abstract:
In multimedia conferencing, multi-point controlling unit (MCU) provides the capabilities to process audio, video and data stream for multi-point conference. The capability of audio processing is basic and requires more for real-time criteria. This paper categorizes and analyzes the schemes, and a new multi-point speech audio mixing scheme using align-to-self weighted algorithm is provided to meet the demand of the practical need of multi-point speech processing. By applying the adaptive mixing algorithms, these high-performance processing schemes do not use the saturation operation which is widely used in multimedia processing. Therefore, no new noise will be added to the output, and they have low complexity and good hearing perceptibility. In the mean time, the schemes are designed for parallel processing, so they can be easily implemented with hardware, such as DSPs, and widely applied in multimedia conferencing systems.
In multimedia conferencing, multi-point controlling unit (MCU) provides the capabilities to process audio, video and data stream for multi-point conference. The capability of audio processing is basic and requires more for real-time criteria. This paper categorizes and analyzes the schemes, and a new multi-point speech audio mixing scheme using align-to-self weighted algorithm is provided to meet the demand of the practical need of multi-point speech processing. By applying the adaptive mixing algorithms, these high-performance processing schemes do not use the saturation operation which is widely used in multimedia processing. Therefore, no new noise will be added to the output, and they have low complexity and good hearing perceptibility. In the mean time, the schemes are designed for parallel processing, so they can be easily implemented with hardware, such as DSPs, and widely applied in multimedia conferencing systems.
2005, 16(1):116-120.
Abstract:
This paper presents a new secret redistribution protocol for threshold sharing schemes that create n shares of the secret for n shareholders. Without having a trusted center, the protocol only requires t (t is the threshold) participants' cooperation and 6t times broadcasting to generate and to distribute the new share. At the end, it is demonstrated that the algorithm has a higher security and is better than the Shuffling scheme and Wong's protocol on reliability and secret management.
This paper presents a new secret redistribution protocol for threshold sharing schemes that create n shares of the secret for n shareholders. Without having a trusted center, the protocol only requires t (t is the threshold) participants' cooperation and 6t times broadcasting to generate and to distribute the new share. At the end, it is demonstrated that the algorithm has a higher security and is better than the Shuffling scheme and Wong's protocol on reliability and secret management.
2005, 16(1):121-134.
Abstract:
As the applications of real-time computing technology are becoming more and more popular in many safety critical domains such as avionics, national defense and transportation systems, field network faces new requirements and challenges because of the coexistence of different kinds of synchronous real-time, asynchronous real-time and non-real-time communication requirements. The realization approach and schedulability analysis of safety critical real-time network are very crucial because of giving a way to solve the problem. Firstly, the shortcomings of the existing COTS network such as Ethernet are described. And then, a high reliable and real time Ethernet communication protocol known as E&TTE (event- and time-triggered Ethernet) based on event- and time-triggered approach is presented. The E&TTE based real time network is flexible, and the communication time is predictable. At the same time, the network scheduling model is constructed, and the global schedulability analysis is done in this paper. The rationality and feasibility of E&TTE protocol is also proven by a concrete example. With E&TTE protocol, the diverse requirements of safety critical real time network can be met better. In addition, the E&TTE protocol can be widely applied to the field control network of ordinary industry systems.
As the applications of real-time computing technology are becoming more and more popular in many safety critical domains such as avionics, national defense and transportation systems, field network faces new requirements and challenges because of the coexistence of different kinds of synchronous real-time, asynchronous real-time and non-real-time communication requirements. The realization approach and schedulability analysis of safety critical real-time network are very crucial because of giving a way to solve the problem. Firstly, the shortcomings of the existing COTS network such as Ethernet are described. And then, a high reliable and real time Ethernet communication protocol known as E&TTE (event- and time-triggered Ethernet) based on event- and time-triggered approach is presented. The E&TTE based real time network is flexible, and the communication time is predictable. At the same time, the network scheduling model is constructed, and the global schedulability analysis is done in this paper. The rationality and feasibility of E&TTE protocol is also proven by a concrete example. With E&TTE protocol, the diverse requirements of safety critical real time network can be met better. In addition, the E&TTE protocol can be widely applied to the field control network of ordinary industry systems.
2005, 16(1):135-144.
Abstract:
Mobile computing brings new challenges and requirements for checkpointing and recovery protocol. Existing checkpointing-only schemes can not guarantee the independent recovery through creating global consistent checkpoints. Message logging schemes based on mobile-MSS-mobile communication that exchanges messages among mobile hosts may incur large contention on the wireless network and high latency for message transmission relative to the direct mobile host to mobile host (m-m) communication. This paper presents a novel recovery protocol for m-m communication, in which two key problems, message order and duplicate message, are effectively solved. A proof of the protocol correctness is also given. Finally, simulation results indicate that the performance of the proposed approach is better than that of the traditional approaches in terms of fail-free and recovery overhead.
Mobile computing brings new challenges and requirements for checkpointing and recovery protocol. Existing checkpointing-only schemes can not guarantee the independent recovery through creating global consistent checkpoints. Message logging schemes based on mobile-MSS-mobile communication that exchanges messages among mobile hosts may incur large contention on the wireless network and high latency for message transmission relative to the direct mobile host to mobile host (m-m) communication. This paper presents a novel recovery protocol for m-m communication, in which two key problems, message order and duplicate message, are effectively solved. A proof of the protocol correctness is also given. Finally, simulation results indicate that the performance of the proposed approach is better than that of the traditional approaches in terms of fail-free and recovery overhead.
2005, 16(1):145-150.
Abstract:
The problem of computing delay-constrained minimum-cost multicast trees is of great interest in the last few years. So far, the Bounded Shortest Multicast Algorithm (BSMA) has been thought to be the best constrained multicast algorithm. However, the large computation time restricts its application. As a global optimizing algorithm, Genetic algorithm (GA) is applied to solve the problem of multicast more and more. GA has more powerful searching ability than traditional algorithm, however, the property of "prematurity" makes it difficult to get a good multicast tree. A Clonal Strategies (CS) based multicast algorithm is presented in this paper, which saliently solves the "prematurity" problem in Genetic based multicast algorithm. Furthermore, the algorithm is accelerated by using an adjustable parameter to reduce the search space. The algorithm has the property of simple realization and flexible control. The simulated results show that CS has better performance than BSMA and GA.
The problem of computing delay-constrained minimum-cost multicast trees is of great interest in the last few years. So far, the Bounded Shortest Multicast Algorithm (BSMA) has been thought to be the best constrained multicast algorithm. However, the large computation time restricts its application. As a global optimizing algorithm, Genetic algorithm (GA) is applied to solve the problem of multicast more and more. GA has more powerful searching ability than traditional algorithm, however, the property of "prematurity" makes it difficult to get a good multicast tree. A Clonal Strategies (CS) based multicast algorithm is presented in this paper, which saliently solves the "prematurity" problem in Genetic based multicast algorithm. Furthermore, the algorithm is accelerated by using an adjustable parameter to reduce the search space. The algorithm has the property of simple realization and flexible control. The simulated results show that CS has better performance than BSMA and GA.
2005, 16(1):151-157.
Abstract:
The problem of secure and efficient revocation of membership without incurring big costs has been considered, but no satisfactory solution was reported. This paper proposes a new revocation method of membership based on the ACJT group scheme. The solution is efficient in that it only needs one multiplication to update the public key for the group manager to exclude one group member, and the signing and verifying procedure is independent of the number of the current and excluded group members. To the best of our knowledge, the signing and verifying procedure in the existing revocation schemes is dependent on the number of either the current or the excluded group members, and thus the group manager needs a heavy computation load to update the public key.
The problem of secure and efficient revocation of membership without incurring big costs has been considered, but no satisfactory solution was reported. This paper proposes a new revocation method of membership based on the ACJT group scheme. The solution is efficient in that it only needs one multiplication to update the public key for the group manager to exclude one group member, and the signing and verifying procedure is independent of the number of the current and excluded group members. To the best of our knowledge, the signing and verifying procedure in the existing revocation schemes is dependent on the number of either the current or the excluded group members, and thus the group manager needs a heavy computation load to update the public key.
2005, 16(1):158-164.
Abstract:
Gnutella is a fully decentralized and unstructured peer-to-peer network. It uses the message broadcasting mechanism of flooding. However, while bringing Gnutella network the characters of high degree of robustness and dynamic, this broadcasting mechanism makes the network give redundant messages that increase exponentially. On basis of resolving Gnutella network message broadcasting mechanism, the paper points out the necessity and feasibility of Gnutella network losing contact, and then bring forward the means which can compartmentalize Gnutella network messages PRI according to the transmitting bandwidth, the time, and the resources which are consumed by servents dealing with all kinds of messages. F-Measure is introduced to connection management, which is usually used to evaluate the performance of searching engine. The paper provides a discarding connection management algorithm, which discards the redundant connection by computation and ensures the maximal attainability of message simultaneously. Finally, the arithmetic example and discussion are given.
Gnutella is a fully decentralized and unstructured peer-to-peer network. It uses the message broadcasting mechanism of flooding. However, while bringing Gnutella network the characters of high degree of robustness and dynamic, this broadcasting mechanism makes the network give redundant messages that increase exponentially. On basis of resolving Gnutella network message broadcasting mechanism, the paper points out the necessity and feasibility of Gnutella network losing contact, and then bring forward the means which can compartmentalize Gnutella network messages PRI according to the transmitting bandwidth, the time, and the resources which are consumed by servents dealing with all kinds of messages. F-Measure is introduced to connection management, which is usually used to evaluate the performance of searching engine. The paper provides a discarding connection management algorithm, which discards the redundant connection by computation and ensures the maximal attainability of message simultaneously. Finally, the arithmetic example and discussion are given.
联系方式
- 《Journal of Software 》
- 主办单位：Institute of Software, CAS, China
- 邮编：100190
- 电话：010-62562563
- 电子邮箱：jos@iscas.ac.cn
- 网址：https://www.jos.org.cn
- 刊号：ISSN 1000-9825
- CN 11-2560/TP
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Copyright: Institute of Software, Chinese Academy of Sciences Beijing ICP No. 05046678-4
Address：4# South Fourth Street, Zhong Guan Cun, Beijing 100190,Postal Code：100190
Phone：010-62562563 Fax：010-62562533 Email：jos@iscas.ac.cn
Technical Support：Beijing Qinyun Technology Development Co., Ltd.
