• ETRI Journal
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• 제21권4호
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• pp.52-64
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• 1999

QoS monitoring is a kind of real-time systems which allows each level of the system to track the ongoing QoS levels achieved by the lower network layers. For these systems, real-time communications between corresponding transport protocol objects is essential for their correct behavior. When two or more entities are employed to perform a certain task as in the case of communication protocols, the capability to do so is called interoperability and considered as the essential aspect of correctness of communication systems. This paper describes a formal approach on modeling and interoperability test case generation of a real-time QoS monitoring protocol. For this, we specify the behavior of flow monitoring of transport layer QoS protocol, i.e., METS protocol, which is proposed to address QoS from an end-to-end's point of view, based on QoS architecture model which includes ATM net work in lower layers. We use a real-time Input/Output finite State Machine to model the behavior of real-time flow monitoring over time. From the modeled real-time I/OFSM, we generate interoperability test cases to check the correctness of METS protocol's flow monitoring behaviors for two end systems. A new approach to efficient interoperability testing is described and the method of interoperability test cases generation is shown with the example of METS protocol's flow monitoring. The current TTCN is not appropriate for testing real-time and multimedia systems. Because test events in TTCN are for message-based system and not for stream-based systems, the real-time in TTCN can only be approximated. This paper also proposes the notation of real-time Abstract Test Suite by means of real-time extension of TTCN. This approach gives the advantages that only a few syntactical changes are necessary, and TTCN and real-time TTCN are compatible. This formal approach on interoperability testing can be applied to the real-time protocols related to IMT-2000, B-ISDN and real-time systems.

• 정보통신설비학회논문지
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• 제3권1호
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• pp.75-87
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• 2004

The mobile industry is waking up to the reality that customers buy 'services', not technology. Thekey is to deliver a variety of differentiated services today and improve them as the advanced technology becomes available. In the increasingly data centric world of the future, the emphasis will be on the provision of a range of services audio, video, data and multimedia and of course speech. As we move closer to the realization of these mobile services in the conglomeration of converged networks, new challenges are being faced by the technology and application developers as well as the service providers to design, test and integrate new products and services. Functionalities like availability, scalability, performance and compatibility have become more important. This paper discusses the new test paradigms in the mobile networks, both from the applications and the protocols perspective.

• 한국산학기술학회논문지
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• 제10권11호
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• pp.3399-3404
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• 2009

RFID 시스템은 리더기가 물체에 부착된 태그의 정보를 무선으로 파악하는 장거리 인식용으로 사용되고 있다. 그렇지만, 각기 구현하는 방식에 조금의 차이가 있어 각 제품들 간의 호환이나, 태그와 리더기 사이의 호환이 원만히 이루어지지 않고 있는 것이 문제점이다. 따라서, 본 연구에서는 몇 가지 서로 다른 프로토콜을 탑재하여 다양한 종류의 태그와 리더기를 검사하고, 고주파 특성과 프로토콜을 동시에 검증할 수 있는 시스템을 설계 및 구현하였다.

• 한국통신학회논문지
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• 제18권10호
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• pp.1572-1581
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• 1993

프로토콜을 명세할때 결정적 유한상태기계(Deterministic Finite State Machine)가 프로토콜의 제어 흐름을 쉽게 나타낼 수 있어서 시험항목 생성시 주로 사용되었으나, 실제의 프로토콜들은 한개의 입력에 의해서 한개 이상의 상태로 천이가 발생하는 비결정성(Nondterminism)문제들을 내포할 수 있으므로 결정적 유한상태기계로는 비결정성 문제를 처리할 수 없다. 따라서 본 논문에서는 프로토콜을 먼저 프로토콜의 비결정성 특성을 잘 나타낼 수 있는 비결정적 유한상태기계(Nondeterministic FSM)로 나타내고, 이를 결정적 유한상태기계를 변환하기 위한 알고리즘을 제시하였다.

• Tuberculosis and Respiratory Diseases
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• 제80권4호
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• pp.344-350
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• 2017

Bronchial asthma is a disease characterized by the condition of airway hyper-responsiveness, which serves to produce narrowing of the airway secondary to airway inflammation and/or various spasm-inducing stimulus. Nonspecific bronchoprovocation testing is an important method implemented for the purpose of diagnosing asthma; this test measures the actual degree of airway hyper-responsiveness and utilizes direct and indirect bronchoprovocation testing. Direct bronchoprovocation testing using methacholine or histamine may have superior sensitivity as these substances directly stimulate the airway smooth muscle cells. On the other hand, this method also engenders the specific disadvantage of relatively low specificity. Indirect bronchoprovocation testing using mannitol, exercise, hypertonic saline, adenosine and hyperventilation serves to produce reactions in the airway smooth muscle cells by liberating mediators with stimulation of airway inflammatory cells. Therefore, this method has the advantage of high specificity and also demonstrates relatively low sensitivity. Direct and indirect testing both call for very precise descriptions of very specific measurement conditions. In addition, it has become evident that challenge testing utilizing each of the various bronchoconstrictor stimuli requires distinct and specific protocols. It is therefore important that the clinician understand the mechanism by which the most commonly used bronchoprovocation testing works. It is important that the clinician understand the mechanism of action in the testing, whether direct stimuli (methacholine) or indirect stimuli (mannitol, exercise) is implemented, when the testing is performed and the results interpreted.

• 한국통신학회논문지
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• 제39C권9호
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• pp.880-886
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• 2014

열차제어시스템은 최근의 컴퓨터 기술의 발달에 따른 자동화 및 지능화에 따라 소프트웨어에의 의존성이 더욱 증가하고 있으며, 동시에 소프트웨어의 오류 내재 가능성이 높아지고 실제 장애발생으로 인한 위험비용도 증가하고 있다. 이에 따라 열차제어시스템 소프트웨어의 무결성 검증이 매우 중요한 이슈가 되고 있으며, 이 중에서 열차제어 소프트웨어 기능안전성 검증을 위한 블랙박스 테스팅 도구의 필요성이 제기되고 있으나, 기존 상용도구들은 사용하기 어렵고 복잡하여 실제 현장에서 적용이 거의 되지 않고 있다. 본 논문에서는 이러한 분석을 바탕으로 열차제어시스템 소프트웨어 기능안전성 검증을 위한 실제 사용하고 있은 인터페이스를 통한 새로운 개념의 블랙박스 테스팅 도구를 제안하였다. 현재 제안한 도구의 설계 및 프로토타입이 개발되어 열차제어시스템 소프트웨어 테스팅에 시범적용 중에 있다.

• 대한수의학회지
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• 제44권2호
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• pp.317-322
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• 2004

This study was performed to evaluate echocardiographic parameters in dogs with experimental mitral regurgitation subjected to dobutamine stress testing. In 8 beagle dogs, a 4-prong grasping forceps was inserted into the left ventricle through the carotid artery with fluoroscopic guidance. The disruption of chordae or mitral valve leaflet was performed. Echocardiographic protocols included quantitative Doppler echocardiography and M-mode measurement for evaluating left ventricle function. After all measurement was obtained at rest, dobutamine was infused incrementally. In stress testing, all measurement also was performed at rest as the same method. In stress Doppler echocardiography, regurgitant fraction and aortic stroke volume was increased significantly (P<0.001). Effective regurgitant orifice and regurgitant volume was not changed. In M-mode examination, fractional shortening was increased significantly at stress test (P<0.001). From the results obtained in this study, it could be suggested that dobutamine stress echocardiography increase left ventricle performance in non-functional mitral regurgitation and quantitative Doppler echocardiography is non-invasive, accurate method in valvular regurgitation.

• 대한핵의학회지
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• 제39권2호
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• pp.107-113
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• 2005

Pharmacologic stress testing for myocardial perfusion imaging is a widely used noninvasive method for the evaluation of known or suspected coronary artery disease. The use of exercise for cardiac stress has been practiced for over 60 years and clinicians are familial with its using. However, there are inevitabe situations in which exorcise stress is inappropriate. A large number of patients with cardiac problems are unable to exercise to their full potential due to comorbidity such as osteoarthritis, vascular disease and pulmonary disease and a standard exercise stress test for myocardial perfusion imaging is suboptimal means for assessment of coronary artery disease. This problem has led to the development of the pharmacologic stress test and to a great increase in its popularity. All of the currently used pharmacologic agents have well-documented diagnostic value. This review deals the physiological actions, clinical protocols, safety, nuclear imaging applications of currently available stress agents and future development of new vasodilating agents.

• 대한수의학회지
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• 제46권1호
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• pp.27-34
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• 2006

This paper describes the slaughter check results of breeding pigs from the Korean Swine Testing Station for the control of endemic diseases. Gross lesions monitored in the present study included those conditions commonly associated with economically significant subclinical herd infections: enzootic pneumonia, pleuropneumonia, pleuritis, atrophic rhinitis, liver white spots, papular dermatitis and ileitis. A total of 128 slaughter pigs were investigated at 4 subsequent tests according to the slaughter check procedures established. The prevalence of enzootic pneumonia, pleuropneumonia and pleuritis in the initial test was 67.9%, 28.6% and 17.9%, respectively. However, these were decreased to 46.7%, 6.7% and 6.7%, respectively, in the last test after implementation of counter measures including clean-up protocols and medication programs (p > 0.05). The mean pneumonic score also significantly decreased from 6.8 in the initial test to 2.8 in the last test. The prevalence of atrophic rhinitis (${\geq}score\;2$) was 32.2% and mean atrophic rhinitis score of 1.1 were recorded. However, no significant improvement of conditions was achieved with the counter measures indicating that atrophic rhinitis was originated from the source herds and lesions developed early in the life. In the initial test, prevalence of liver white spots and papular dermatitis lesions was 21.4% and 25.0%, respectively. These conditions were cleaned by the implementation of parasite control measures with all-in all-out, strict clean-up protocols and proper medications adopted in the present study (liver white spots, p = 0.0124; papular dermatitis lesions, p = 0.0055). The prevalence of ileitis lesions in slaughter pigs from the initial test was 28.6%, it could be gradually reduced by the use of repeated treatments and control measures but the effect was not so significant (p > 0.05). In conclusion, slaughter check procedures were successfully established and applied for the control of endemic diseases in the Korean Swine Testing Station.

• Wind and Structures
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• 제25권3호
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• pp.233-259
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• 2017

Investigations on simulated near-surface atmospheric boundary layer (ABL) in an open-jet facility are carried out by conducting experimental tests on small-scale models of low-rise buildings. The objectives of the current study are: (1) to determine the optimal location of test buildings from the exit of the open-jet facility, and (2) to investigate the scale effect on the aerodynamic pressure characteristics. Based on the results, the newly built open-jet facility is well capable of producing mean wind speed and turbulence profiles representing open-terrain conditions. The results show that the proximity of the test model to the open-jet governs the length of the separation bubble as well as the peak roof pressures. However, test models placed at a horizontal distance of 2.5H (H is height of the wind field) from the exit of the open-jet, with a width that is half the width of the wind field and a length of 1H, have consistent mean and peak pressure coefficients when compared with available results from wind tunnel testing. In addition, testing models with as large as 16% blockage ratio is feasible within the open-jet facility. This reveals the importance of open-jet facilities as a robust tool to alleviate the scale restrictions involved in physical investigations of flow pattern around civil engineering structures. The results and findings of this study are useful for putting forward recommendations and guidelines for testing protocols at open-jet facilities, eventually helping the progress of enhanced standard provisions on the design of low-rise buildings for wind.