Globally, traditional power systems are rapidly transforming towards the adoption of smart grid platforms. Substations which are at the center of the electric power transformation from the power plant are changing to ...Globally, traditional power systems are rapidly transforming towards the adoption of smart grid platforms. Substations which are at the center of the electric power transformation from the power plant are changing to IEC 61850 based digital substations. Therefore, within substation, there is a growing demand for the IEC 61850 based Intelligent Electronic Devices (IEDs). The operation of multiple manufacturers of IEDs in a single digital substation network increases the need for IEC 61850 communications specification conformance diagnosis to ensure interoperability for efficient data exchange between IEDs. The IEC 61850-10 presents test items for diagnosing communication specification conformance. There are many test tools available in the market today to test the compliance of the IEC 61850 communications specifications to the IED. In this paper, we propose a model-based diagnostic method for IED communication conformance testing. The proposed model-based software therefore uses the “drag and drop” technique to select the various IEC 61850 communication services (objects) required to design the test case in a user friendly Graphical User Interface (GUI). This makes the service conformance testing more flexible for test engineers and system integrators especially in situations that require test case modifications. Also, the proposed software tool makes it easy to understand the various IEC 61850 services using the friendly GUI.展开更多
In this paper, a conformance test platform is built for intelligent electronic devices (IEDs) from different manufacturers based on IEC 61850 communication protocol. A conformance test of time delay of message transmi...In this paper, a conformance test platform is built for intelligent electronic devices (IEDs) from different manufacturers based on IEC 61850 communication protocol. A conformance test of time delay of message transmission between two IEDs, made by the same or different manufacturers, is performed. The conformance test platform, as well as the test results provide a helpful reference for IEC 61850 implementation.展开更多
The session initiation protocol (SIP) is a signaling protocol for Internet telephony, multimedia conferencing, presence, event notification, and instant messaging. With the gaining popularity, more and more SIP implem...The session initiation protocol (SIP) is a signaling protocol for Internet telephony, multimedia conferencing, presence, event notification, and instant messaging. With the gaining popularity, more and more SIP implementations have been developed and deployed. How to guarantee the conformance of those SIP implementations is the key point of interconnection and interoperation among them. This paper proposes the test method and architecture for the SIP protocol based on the IPv6 tester system. Tree and tabular combined notation (TTCN-2) is adopted to describe the test suite. With an enhanced reference implementation, the data-processing ability to the original test system has been greatly improved. In the following test practices, some errors have been found in the SIP entities under test. It is proved that the proposed test method and architecture are effective to verify the conformance of the SIP entities, and the result of the conformance test may provide helpful reference to the development of SIP products.展开更多
We present a method of generating test cases from the software specifications which are modeled by nondeterministic finite state machines. It is applicable to both nondeterministic and deterministic finite state mach...We present a method of generating test cases from the software specifications which are modeled by nondeterministic finite state machines. It is applicable to both nondeterministic and deterministic finite state machines. When applied to deterministic machines, this method yields usually smaller test suites with full fault coverage than the existing methods that also assure full fault coverage. In particular, the proposed mehod can be used to test the control portion of software specified in the formalspecification languages SDL or ESTELLE.展开更多
Exchanging simulation models is currently of utmost importance.To improve interoperability between suppliers and original equipment manufacturers(OEMs),the functional mock-up interface(FMI)is exchanged in a standard f...Exchanging simulation models is currently of utmost importance.To improve interoperability between suppliers and original equipment manufacturers(OEMs),the functional mock-up interface(FMI)is exchanged in a standard format called functional mock-up unit(FMU).Since its first release,many simulation tools took the initiative to support FMI.However,since then,there have been many complaints stating that exchanging models via FMI does not work as stable as expected.The reason usually turned out to be the implementation of tool vendors that sometimes fail to comply with the standard fully.This paper introduces a methodology for testing FMI compliance of importing simulation tools using a set of reference FMUs.The standard defines the implementation of FMI functions calling sequence in a state machine.Therefore,conformance testing(also called fault detection)from automata theory is utilized to produce reference FMUs based on the FMI state-machine.展开更多
This paper describes the ISUP (ISDN User Part of CCSS7) conformance testing theory and method according to CCITT and China national standards, and presents a successful ISUP protocol conformance testing system in detail.
The objective of conformance testing is to determine whether an implementation under test (IUT) conforms to its specification. In distributed test architecture where there are multiple remote testers, the objective ca...The objective of conformance testing is to determine whether an implementation under test (IUT) conforms to its specification. In distributed test architecture where there are multiple remote testers, the objective can be complicated by the fact that testers may encounter controllability and observability problems during the application of a test sequence. A certain amount of work has been done in the area of generating test sequence that is free from these problems. However, few researchers investigate them from the aspect of test execution. This work studies the test execution phase when test sequences are applied to the imple- mentation and it is pointed out that controllability and observability problems can be resolved if and only if the test system im- plements some timing constraints. When determining these constraints, the dynamic time information during test is taken into account, which reduces the test execution time and improves test efficiency further.展开更多
Formal methods for test sequence generation from FSM have been studied widely andthoroughly,but most real communication systems can only be modeled as EFSM exactly.Data portion in EFSM brings difficulties for test sui...Formal methods for test sequence generation from FSM have been studied widely andthoroughly,but most real communication systems can only be modeled as EFSM exactly.Data portion in EFSM brings difficulties for test suite generation.In this paper,the strategyof generating test suite from protocols modelled as EFSM is presented.This strategy consid-ers testing of both the control portion and data portion of protocols.A software,the testsuite generation system(TSGS)based on above strategy,is introduced.展开更多
This paper rejuvenates the notion of conformance testing in order to assess the security of networks. It leverages the Testing and Test Control Notation Version 3 (TTCN-3) by applying it to a redefined notion of <i...This paper rejuvenates the notion of conformance testing in order to assess the security of networks. It leverages the Testing and Test Control Notation Version 3 (TTCN-3) by applying it to a redefined notion of <i>System under Test</i> (<i>SUT</i>). Instead of testing, as it is classically done, a software/firmware/ hardware element, an intangible object, namely the network, is tested in order to infer some of its security properties. After a brief introduction of TTCN-3 and Titan, its compilation and execution environment, a couple of use cases are provided to illustrate the feasibility of the approach. The pros and cons of using TTCN-3 to implement a scalable and flexible network testing environment are discussed.展开更多
As production automation systems have been and are becoming more and more complex, the task of quality assurance is increasingly challenging. Model-based testing is a research field addressing this challenge and many ...As production automation systems have been and are becoming more and more complex, the task of quality assurance is increasingly challenging. Model-based testing is a research field addressing this challenge and many approaches have been suggested for different applications. The goal of this paper is to review these approaches regarding their suitability for the domain of production automation in order to identify current trends and research gaps. The different approaches are classified and clustered according to their main focus which is either testing and test case generation from some form of model automatons, test case generation from models used within the development process of production automation systems, test case generation from fault models or test case selection and regression testing.展开更多
Korea Electric Power Corporation in charge of the power IT project ＂Development of Prototype for Advanced Substation Automation System based on the Digital Control Technology＂, is performing the verification of perf...Korea Electric Power Corporation in charge of the power IT project ＂Development of Prototype for Advanced Substation Automation System based on the Digital Control Technology＂, is performing the verification of performance of the substation automation system based on IEC 61850. In order to verify a transformer protective lED that might be operating in substation automation system, the new standardized document and procedures are required in the aspect of the utility like KEPCO. But there is nothing to describe systematically how to verify IEC 6 1850 based lED in the system environment except an individual IED testing way. This paper will present the substation automation system based ways and procedures to verify the protective function of the IED using UML （Unified Modeling Language）.展开更多
The digital substation system consists of an Intelligent Electronic Device (IED) which requires information for the supervision, protection, and control, as well as a client operating system for substation operation. ...The digital substation system consists of an Intelligent Electronic Device (IED) which requires information for the supervision, protection, and control, as well as a client operating system for substation operation. IEC 61850 communication standard has been defined for information exchange between heterogeneous digital devices in such substations. Currently, the Korea Electric Power Corporation (KEPCO) digital substation system uses unbuffered reporting and Generic Object Oriented Substation Events (GOOSE) communication functions for monitoring, protection and control automation. However, it is expected that the Setting Group function will be needed to operate adaptive intelligent substation system. The Setting Group function is advantageous in that it is possible to change the setting of the IED in one unified way through the client operating system, rather than changing the correction value of an IED through different manufacturer-based engineering tools. In order to utilize the Setting Group function of the IED in real substation scenario, it is necessary to test both the communication function with the host operating device and the electric functional test to ensure that correction value is properly changed. In this paper, we introduce the IEC 61850 Setting Group function, and propose a method that can integrate communication function and electrical function test of an IED conforming to the setting group functionality. We also tested the Setting Group function of the actual IED device through the proposed integrated functional test method and analyzed the results. We were able to simplify the process of testing both the electrical and communication signals in digital substations.展开更多
This paper presents an approach for extending the constraint model defined for conformity testing of a given method of class to its overriding method in subclass using inheritance principle. The first objective of the...This paper presents an approach for extending the constraint model defined for conformity testing of a given method of class to its overriding method in subclass using inheritance principle. The first objective of the proposed work is to find the relationship between the test model of an overriding method and its overridden method using the constraint propagation. In this context the approach shows that the test cases developed for testing an original method can be used for testing its overriding method in a subclass and then the number of test cases can be reduced considerably. The second objective is the use of invalid data which do not satisfy the precondition constraint and induce valid output values for introducing a new concept of test called secure testing. The implementation of this approach is based on a random generation of test data and analysis by formal proof.展开更多
The overuse of clinical laboratory services has been documented for many years. This overuse use does not contribute to the quality of medical care, does not shorten hospital stay, nor reduce mortality. The utilizatio...The overuse of clinical laboratory services has been documented for many years. This overuse use does not contribute to the quality of medical care, does not shorten hospital stay, nor reduce mortality. The utilization of diagnostic laboratories has increased over the last decade around the world. This increased laboratory use is appropriate if it allows accurate diagnoses to be made, ideal treatment to be identified and monitored, accurate prognoses to be established, and patients’ hospital stays to be shortened. Thus, improving the appropriateness of testing behavior and reducing the number of laboratory tests have been recognized as essential parts of quality improvement program. In this study, the effectiveness of a computer-based system in improving the laboratory test-ordering in a general hospital was investigated. The study was conducted through four stages, the preparation stage, the pre-intervention stage, the post-intervention 1) stage and post-intervention 2) stage. Guideline and computer system were developed during preparation stage. Medical records were reviewed against guideline recommendations before any intervention during the pre-intervention stage, after guideline dissemination through educational workshops during the post intervention 1) stage, and after implementation of the computer system with the new requesting form during the post intervention 2) stage. The study revealed that the computer-based system achieved a statistically significant increase in the percentage of appropriate use from 44.6% in the post-intervention 1) stage to 55.6%, and a statistically significant increase in the compliance with guideline by prescriber as well as increased in guideline conformity rate from 16.7% in the post-intervention 1) stage to 32.5% in the post-intervention 2) stage, and decreased in the percentage of prescribers whose level was unsatisfactory from 85.4% the post-intervention 1) stage to 66.7% in the post-intervention 2) stage.展开更多
文摘Globally, traditional power systems are rapidly transforming towards the adoption of smart grid platforms. Substations which are at the center of the electric power transformation from the power plant are changing to IEC 61850 based digital substations. Therefore, within substation, there is a growing demand for the IEC 61850 based Intelligent Electronic Devices (IEDs). The operation of multiple manufacturers of IEDs in a single digital substation network increases the need for IEC 61850 communications specification conformance diagnosis to ensure interoperability for efficient data exchange between IEDs. The IEC 61850-10 presents test items for diagnosing communication specification conformance. There are many test tools available in the market today to test the compliance of the IEC 61850 communications specifications to the IED. In this paper, we propose a model-based diagnostic method for IED communication conformance testing. The proposed model-based software therefore uses the “drag and drop” technique to select the various IEC 61850 communication services (objects) required to design the test case in a user friendly Graphical User Interface (GUI). This makes the service conformance testing more flexible for test engineers and system integrators especially in situations that require test case modifications. Also, the proposed software tool makes it easy to understand the various IEC 61850 services using the friendly GUI.
文摘In this paper, a conformance test platform is built for intelligent electronic devices (IEDs) from different manufacturers based on IEC 61850 communication protocol. A conformance test of time delay of message transmission between two IEDs, made by the same or different manufacturers, is performed. The conformance test platform, as well as the test results provide a helpful reference for IEC 61850 implementation.
基金the National Natural Science Foundation of China (No. 60572082)
文摘The session initiation protocol (SIP) is a signaling protocol for Internet telephony, multimedia conferencing, presence, event notification, and instant messaging. With the gaining popularity, more and more SIP implementations have been developed and deployed. How to guarantee the conformance of those SIP implementations is the key point of interconnection and interoperation among them. This paper proposes the test method and architecture for the SIP protocol based on the IPv6 tester system. Tree and tabular combined notation (TTCN-2) is adopted to describe the test suite. With an enhanced reference implementation, the data-processing ability to the original test system has been greatly improved. In the following test practices, some errors have been found in the SIP entities under test. It is proved that the proposed test method and architecture are effective to verify the conformance of the SIP entities, and the result of the conformance test may provide helpful reference to the development of SIP products.
文摘We present a method of generating test cases from the software specifications which are modeled by nondeterministic finite state machines. It is applicable to both nondeterministic and deterministic finite state machines. When applied to deterministic machines, this method yields usually smaller test suites with full fault coverage than the existing methods that also assure full fault coverage. In particular, the proposed mehod can be used to test the control portion of software specified in the formalspecification languages SDL or ESTELLE.
文摘Exchanging simulation models is currently of utmost importance.To improve interoperability between suppliers and original equipment manufacturers(OEMs),the functional mock-up interface(FMI)is exchanged in a standard format called functional mock-up unit(FMU).Since its first release,many simulation tools took the initiative to support FMI.However,since then,there have been many complaints stating that exchanging models via FMI does not work as stable as expected.The reason usually turned out to be the implementation of tool vendors that sometimes fail to comply with the standard fully.This paper introduces a methodology for testing FMI compliance of importing simulation tools using a set of reference FMUs.The standard defines the implementation of FMI functions calling sequence in a state machine.Therefore,conformance testing(also called fault detection)from automata theory is utilized to produce reference FMUs based on the FMI state-machine.
文摘This paper describes the ISUP (ISDN User Part of CCSS7) conformance testing theory and method according to CCITT and China national standards, and presents a successful ISUP protocol conformance testing system in detail.
文摘The objective of conformance testing is to determine whether an implementation under test (IUT) conforms to its specification. In distributed test architecture where there are multiple remote testers, the objective can be complicated by the fact that testers may encounter controllability and observability problems during the application of a test sequence. A certain amount of work has been done in the area of generating test sequence that is free from these problems. However, few researchers investigate them from the aspect of test execution. This work studies the test execution phase when test sequences are applied to the imple- mentation and it is pointed out that controllability and observability problems can be resolved if and only if the test system im- plements some timing constraints. When determining these constraints, the dynamic time information during test is taken into account, which reduces the test execution time and improves test efficiency further.
基金Sponsored by Natural Sclence Foundation of China.
文摘Formal methods for test sequence generation from FSM have been studied widely andthoroughly,but most real communication systems can only be modeled as EFSM exactly.Data portion in EFSM brings difficulties for test suite generation.In this paper,the strategyof generating test suite from protocols modelled as EFSM is presented.This strategy consid-ers testing of both the control portion and data portion of protocols.A software,the testsuite generation system(TSGS)based on above strategy,is introduced.
文摘This paper rejuvenates the notion of conformance testing in order to assess the security of networks. It leverages the Testing and Test Control Notation Version 3 (TTCN-3) by applying it to a redefined notion of <i>System under Test</i> (<i>SUT</i>). Instead of testing, as it is classically done, a software/firmware/ hardware element, an intangible object, namely the network, is tested in order to infer some of its security properties. After a brief introduction of TTCN-3 and Titan, its compilation and execution environment, a couple of use cases are provided to illustrate the feasibility of the approach. The pros and cons of using TTCN-3 to implement a scalable and flexible network testing environment are discussed.
文摘As production automation systems have been and are becoming more and more complex, the task of quality assurance is increasingly challenging. Model-based testing is a research field addressing this challenge and many approaches have been suggested for different applications. The goal of this paper is to review these approaches regarding their suitability for the domain of production automation in order to identify current trends and research gaps. The different approaches are classified and clustered according to their main focus which is either testing and test case generation from some form of model automatons, test case generation from models used within the development process of production automation systems, test case generation from fault models or test case selection and regression testing.
文摘Korea Electric Power Corporation in charge of the power IT project ＂Development of Prototype for Advanced Substation Automation System based on the Digital Control Technology＂, is performing the verification of performance of the substation automation system based on IEC 61850. In order to verify a transformer protective lED that might be operating in substation automation system, the new standardized document and procedures are required in the aspect of the utility like KEPCO. But there is nothing to describe systematically how to verify IEC 6 1850 based lED in the system environment except an individual IED testing way. This paper will present the substation automation system based ways and procedures to verify the protective function of the IED using UML （Unified Modeling Language）.
文摘The digital substation system consists of an Intelligent Electronic Device (IED) which requires information for the supervision, protection, and control, as well as a client operating system for substation operation. IEC 61850 communication standard has been defined for information exchange between heterogeneous digital devices in such substations. Currently, the Korea Electric Power Corporation (KEPCO) digital substation system uses unbuffered reporting and Generic Object Oriented Substation Events (GOOSE) communication functions for monitoring, protection and control automation. However, it is expected that the Setting Group function will be needed to operate adaptive intelligent substation system. The Setting Group function is advantageous in that it is possible to change the setting of the IED in one unified way through the client operating system, rather than changing the correction value of an IED through different manufacturer-based engineering tools. In order to utilize the Setting Group function of the IED in real substation scenario, it is necessary to test both the communication function with the host operating device and the electric functional test to ensure that correction value is properly changed. In this paper, we introduce the IEC 61850 Setting Group function, and propose a method that can integrate communication function and electrical function test of an IED conforming to the setting group functionality. We also tested the Setting Group function of the actual IED device through the proposed integrated functional test method and analyzed the results. We were able to simplify the process of testing both the electrical and communication signals in digital substations.
文摘This paper presents an approach for extending the constraint model defined for conformity testing of a given method of class to its overriding method in subclass using inheritance principle. The first objective of the proposed work is to find the relationship between the test model of an overriding method and its overridden method using the constraint propagation. In this context the approach shows that the test cases developed for testing an original method can be used for testing its overriding method in a subclass and then the number of test cases can be reduced considerably. The second objective is the use of invalid data which do not satisfy the precondition constraint and induce valid output values for introducing a new concept of test called secure testing. The implementation of this approach is based on a random generation of test data and analysis by formal proof.
文摘The overuse of clinical laboratory services has been documented for many years. This overuse use does not contribute to the quality of medical care, does not shorten hospital stay, nor reduce mortality. The utilization of diagnostic laboratories has increased over the last decade around the world. This increased laboratory use is appropriate if it allows accurate diagnoses to be made, ideal treatment to be identified and monitored, accurate prognoses to be established, and patients’ hospital stays to be shortened. Thus, improving the appropriateness of testing behavior and reducing the number of laboratory tests have been recognized as essential parts of quality improvement program. In this study, the effectiveness of a computer-based system in improving the laboratory test-ordering in a general hospital was investigated. The study was conducted through four stages, the preparation stage, the pre-intervention stage, the post-intervention 1) stage and post-intervention 2) stage. Guideline and computer system were developed during preparation stage. Medical records were reviewed against guideline recommendations before any intervention during the pre-intervention stage, after guideline dissemination through educational workshops during the post intervention 1) stage, and after implementation of the computer system with the new requesting form during the post intervention 2) stage. The study revealed that the computer-based system achieved a statistically significant increase in the percentage of appropriate use from 44.6% in the post-intervention 1) stage to 55.6%, and a statistically significant increase in the compliance with guideline by prescriber as well as increased in guideline conformity rate from 16.7% in the post-intervention 1) stage to 32.5% in the post-intervention 2) stage, and decreased in the percentage of prescribers whose level was unsatisfactory from 85.4% the post-intervention 1) stage to 66.7% in the post-intervention 2) stage.
