• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.5
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• pp.615-621
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• 2009

Since GPS receivers and INS algorithms do not work properly in the spinning vehicles due to change of the GPS signal and excess of the measurement limitation of the gyroscope, conventional GPS/INS integrated navigation systems do not provide accurate navigation outputs. This paper proposes a design method for GPS/INS integrated navigation systems of spinning vehicles. A special GPS receiver with a signal tracking loop for changed GPS signal caused by spinning and an INS with a roll estimation method are configured and the conventional integration filter is combined. The proposed method was verified through comparison of the navigation results. The result of the proposed method for the spinning vehicle was similar to that of the conventional navigation system without spinning.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.37 no.8
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• pp.767-773
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• 2009

This research have introduced wavelet signal processing technic for improving navigation signals. INS signals can be distorted with conventional pre-filtering method such as low-pass filtering by unwanted smoothing on real signals. But in this paper, wavelet thresholding method is implemented to INS signal to denoise for INS-GPS integrated system. This method reduces signal noise but not distorts the rapid varing signal. And this paper applied thresholding to INS-GPS integrated navigation system and improved navigation performance.

• Journal of the Korea Institute of Military Science and Technology
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• v.2 no.2
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• pp.186-196
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• 1999

The CPS provides data with long-term stability independent of passed time and the INS provides high-rate data with short-term stability. By integrating these complementary systems, a highly accurate navigation system can be achieved. In this paper, a loosely-coupled GPS/INS integration system is designed. It is a simple structure and is easy to implement and preserves independent navigation capability of GPS and INS. The integration system consists of a NCU, an IMU, a GPS receiver, and a monitoring system. The navigation algorithm in the NCU is designed under the multi-tasking environment based on a real-time kernel system and the monitoring system is designed using the Visual C++. The integrated Kalman filter is designed as a feedback formed 15-state filter, in which the states are position errors, velocity errors, attitude errors and sensor bias errors. The van test result shows that the integrated system provides more accurate navigation solution then the inertial or the GPS-alone navigation system.

• Journal of Genetic Medicine
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• v.21 no.1
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• pp.14-21
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• 2024

Infantile nystagmus syndrome (INS) refers to congenital forms of nystagmus that are present at birth or during infancy. This syndrome may be caused by afferent visual system disorders or abnormal development of the ocular motor system. INS is a genetically heterogeneous disorder for which there are more than 100 causative genes. Since applying clinical tests for the differential diagnosis of INS can be challenging in early infancy and children, genetic testings such as next-generation sequencing are becoming more important for achieving accurate diagnoses. An improved understanding of the molecular mechanisms of INS may also lead to the development of gene-based therapies for INS. These advantages of genetic testing have the potential to change the diagnostic paradigm of patients with INS. However, the diagnostic pathway based on genetic testing still has several limitations in terms of the therapeutic effect and methodology. This review summarizes genetic and clinical features of INS, and discusses the promise and pitfalls of genetic testing in INS.

• International Journal of Control, Automation, and Systems
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• v.6 no.4
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• pp.534-543
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• 2008

To use the Global Positioning System (GPS) carrier phase measurement for precise positioning, the integer ambiguities at the early stage of most algorithms must be determined. Furthermore, if a precise positioning is to be applied to real time navigation, fast determination and validation methods for integer ambiguity are essential. In this paper, the Wald test that simultaneously determines and validates integer ambiguities is used with assistance of the Inertial Navigation System (INS) to improve its performance. As the Wald test proceeds, it assigns a higher probability to the candidate that is considered to be true at each time step. The INS information is added during the Wald test process. Large performance improvements were achieved in convergence time as well as in requiring fewer observable GPS satellites. To test the performance improvement of the Wald test with the INS information, experimental tests were conducted using a ground vehicle. The vehicle moved in a prescribed trajectory and observed seven GPS satellites. To verify the effect of the INS information on the Wald test, the convergence times were compared with cases that considered the INS information and cases that did not consider the INS information. The results show that the benefits of using the INS were emphasized as fewer GPS satellites were observable. The performance improvement obtained by the proposed algorithm was shown through the fast convergence to the true hypothesis when using the INS measurements.

• Journal of the Korea Institute of Military Science and Technology
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• v.22 no.2
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• pp.197-206
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• 2019

Safe aircraft requires highly reliable navigation information. The traditionally used inertial navigation system (INS) often displays faulty location information due to its innate errors. To overcome this, the INS/GNSS or INS/TRN integrated navigation can be used. However, GNSS is vulnerable to jamming and spoofing, while TRN can be degraded in the flat and repetitive terrains. In this paper, to improve the performance and ensure the high reliability of the navigation system, the INS/GNSS/TRN integrated navigation based on federated filter is designed. Master filter of the integrated navigation uses the estimates and covariances of two local filters - INS/GNSS and INS/TRN integrated filters. The local filters are designed with the EKF that is feedforward type and composed of the 17st state variables. And the INS/GNSS integrated navigation includes the barometer error compensation method. Finally, the proposed INS/GNSS/TRN integrated navigation is verified by vehicle and captive flight tests.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.04a
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• pp.39-44
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• 2004

In this thesis, two test flights were conducted in Gwacheon and Suwon area to evaluate the performance of accuracy and efficiency through the analysis of results among the three photogrammetric methods, that is, traditional photogrammetry, GPS -Photogrammetry and GPS/INS-Photogrammetry. Test results shows that a large variety of advantages of GPS-Photogrammetry and GPS/INS-Photogrammetry against traditional photogrammetry is to be verified. Especially, the number of ground control points for the exterior orientation could be saved more than 70-80%, and the cost for map production 30-50%, respectively. In addition, it was convinced that the large reduction of control points has not any effect on the block accuracy. It was also proved that the number of required ground control points for GPS/INS-Photogrammetry, is similar to that of GPS-Photogrammetry. Therefore it should be noted that GPS -Photogrammetry is more efficient in the aspect of reduction of mapping cost against GPS/INS-Photogrammetry, installing only an existing GPS receiver on survey aircraft to avoid high economic burden of procurement for integrated GPS/INS equipment.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.974-977
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• 2003

The GPS/INS integration system navigation can provide improved navigation performance and has been widely used as a main navigation system for military and commercial vehicles. When two navigation systems are tightly coupled and the structure is complicated, a fault in either the GPS or the INS can lead to a disastrous failure of the whole integration system. This paper proposes a real-time fault detection method for an AGPS/INS integration system. The proposed fault detection method comprises a BIT and a fault detection algorithm based on chi-square test. It is implemented by real-time software modules to apply the AGPS/INS integration system and van test is carried out to evaluate its performance.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2006.04a
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• pp.151-158
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• 2006

As GPS 'selective availability' was turned off in 2000, GPS related fields and markets are explosively extended. In mapping area, GPS/INS aided photogrammetry proved it is much cost and time effective method keeping enough accuracy as compared with traditional photogrammetry works. The advantage of GPS/INS integration is interdependence. Even if GPS signal was blocked in some time, the position accuracy is not affected. In this study, various GPS signal time gap was used in GPS/INS AT process. Field surveyed ground points were used in accuracy check with GPS/INS AT check points. And the result showed enough accuracy of photogrammetry work rule of NGII. y.

• 한국약용작물학회:학술대회논문집
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• 2011.09a
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• pp.178-179
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• 2011