• Journal of Electrical Engineering and Technology
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• v.6 no.4
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• pp.563-572
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• 2011

Reliability is an essential factor in a navigation system. Therefore, an integrity monitoring system is considered one of the most important parts in an avionic navigation system. A fault due to systematic malfunctioning definitely requires integrity reinforcement through systematic analysis. In this paper, we propose a method to detect faults of the GPS signal by using a distributed nonlinear filter based probability test. In order to detect faults, consistency is examined through a likelihood ratio between the main and auxiliary particle filters (PFs). Specifically, the main PF which includes all the measurements and the auxiliary PFs which only do partial measurements are used in the process of consistency testing. Through GPS measurement and the application of the autonomous integrity monitoring system, the current study illustrates the performance of the proposed fault detection algorithm.

• Journal of the Korean Society of Safety
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• v.30 no.3
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• pp.107-113
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• 2015

The goal of this paper is to investigate structural integrity factors of RMI(reflective metal insulation) to confirm the design requirements in nuclear power plant. Currently, a glass wool insulation is using now, but it will gradually be replaced with the reflective metal insulation maded by stainless steel plates. The main function of an insulation is to minimize a heat loss of vessel and pipes in RCS(reactor coolant system). It has to maintain structural a integrity in nuclear power plant life duration. In this study, the structural integrity analysis was carried out both multi-plate and outer shell plate by using a static analysis and experimental test. First, inner multi-plate has a self support structure for being air space. Because the effect of total static weight in multi-layer plate is low, a plate collapse possibility is not high. Considering optimum thin plate pressing process, it has to pre-check the basic physical properties. Second, the outer segment thickness and stiffener shape are verified by the numerical static analysis, and sample test for both type of panel and cylindrical pipe model.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.40 no.9
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• pp.760-770
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• 2012

In order to provide precision approach service based on GBAS, air navigation service providers should validate the GBAS system performance against international standard requirements and receive approval. The GBAS manufacturer should define integrity threat, analyze the integrity monitors and evaluate performance of the implemented monitors to verify integrity performance which is critical to the aircraft safety. This paper describes a statistical test result to evaluate performance of the code carrier divergence monitors implemented in KARI Integrity Monitor System software. The paper introduces analysis and test procedure which is developed for the performance evaluation and describes the analysis, the test scenario generation and the test results. The results show that the implemented monitors can detect the expected minimum detectable errors with satisfying the probability of missed detection requirements.

• 유체기계공업학회:학술대회논문집
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• 2002.12a
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• pp.419-424
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• 2002

The HANARO, a multi-purpose research reactor of 30 MWth open-tank-in-pool type, has been under normal operation since its initial criticality In February, 1995. Many experiments should be safely performed to activate the utilization of the HANARO. A flow simulation facility is being developed for the endurance test of reactivity control units for extended life times and the verification of structural integrity of those experimental facilities prior to loading in the HANARO. This test facility is composed of three major parts; a half-core structure assembly, flow circulation system and support system. The flow circulation system is composed of a circulation pump, a core flow pipe, a core bypass flow pipe and instruments. The system is to be filled with de-mineralized water and the flow should be met the design flow to simulate similar flow characteristics in the core channel of the half-core test facility to the HANARO. This paper, therefore, describes an analytical analysis to study the flow behavior of the system. The computational flow analysis has been performed for the verification of system pressure variation through the three-dimensional analysis program with standard k-$\epsilon$ turbulence model and for the verification of the structural piping integrity through the finite element method. The results of the analysis are satisfied the design requirements and structural piping integrity of flow circulation system.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.759-762
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• 1999

The concrete structures possessing good structural integrity can face durability problems due to deteriorations of concrete structures under various environmental conditions. The durability problems weaken the structural integrity in the long run. Especially, the excessive use of sea sand causes serious reinforcement corrosion and carbonation in concrete structures. An accelerated test is often used to predict deterioration as a qualitative measure, but without long term exposure test results or understanding of the relationship between the accelerated test and the long term exposure test, the accelerated test result alone can not be used effectively as a quantitative measure. In this paper, a methodology is proposed to predict the long term deteriorations, based on the result of the short-term accelerated test, of concrete containing different contents of chloride ions. Then, the correlation between two results on the steel corrosion ratio and the carbonation depth is analyzed for concrete with different chloride contents.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.4 no.2
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• pp.29-33
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• 2008

As the measures of nuclear power plant utilities and manufacturers to reduce the defects of tube expansion region during manufacturing steam generators, many types of NDEs(Non-Destructive Examinations) are conducted to inspect the expansion region. The expansion region of tube is subject to degrade because of stress concentration induced by tube expansion, sludge pile and high temperature. So the inspections for tube expansion region have been reinforced. Liquid penetrant test, helium leak test, Bobbin profile test and hydraulic test are performed to confirm the integrity of tube expanded by hydraulic expansion method. Liquid penetrant test and helium leak test are used to inspect seal weld region on tubesheet end part. Bobbin Profile test is used to inspect fully the expanded region of steam generator tube. Hydraulic test finally verifies the integrity of seal weld region on tubesheet end part.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1211-1215
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• 2003

Pressure tubes are major component of nuclear reactor, but only selected samples are periodically examined due to numerous numbers of tubes. Current in-service inspection result show there is high probability of flaw existence at un-inspected pressure tube. Probabilistic analysis is applied in this study for the integrity assessment of un-inspected pressure tube. But all the current integrity evaluations procedures are based on conventional deterministic approaches. So many integrity evaluation parameters are not directly apply to probabilistic analysis. As a result of this study failure assessment diagram are proposed based on test data.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.10
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• pp.32-39
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• 2006

An acoustic emission technique was applied to the structural strength test for the structural integrity evaluation of the nozzle assembly. These AE results were compared with data from the strain gages and displacement transducer. NDT using X-ray technique was performed to improve the test reliability before and after each test. In this structural integrity evaluation of the nozzle assembly, the internal crack initiation in the structure could not be precisely revealed by the strain and displacement results but the location and load level of the initiated crack could be precisely evaluated by using AE technique. From this test, it was proven that some new cracks can be generated in composite liner of nozzle assembly under the unexpected load due to interference between obturator and nozzle and these can be a cause of the unexpected abnormal failure.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1441_1441
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• 2009

This paper describes performance of sealing integrity and bending strain of HV polymeric bushing with thermal mechanical test. Generally the properties of FRP tube can be influenced by the winding angle, wall thickness and winding tension. As a results, multi winding bushing shows that it has max deflection in the range of 16.5~16.9 mm.

• The Journal of Korean Academic Society of Nursing Education
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• v.21 no.4
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• pp.499-508
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• 2015

Purpose: This study was conducted in order to determine the extent of ego integrity and to confirm the association between the sense of ego integrity and integrated loneliness, social support, and social activities. Methods: For this study, 146 elderly people participated. The data was analyzed with SPSS/WIN 21.0, using descriptive statistics, t-test, ANOVA, correlation analysis, and hierarchical regression analysis. Results: In regards to differences between ego integrity according to general characteristics of subjects, there was a statistically significant difference in education (F=4.13, p=.007). In elderly living alone, ego integrity was significantly positive correlated with social support and social activities, but negative correlated with loneliness. These variables explained 43.2% of the sense of ego integrity. Conclusion: The study suggested that nursing programs and social activity programs designed to aid the elderly living alone must focus on reducing loneliness, as well as increasing social support and social activities, while taking education into consideration. Also, these programs should strive to build social support systems.