• Journal of the Korean Geotechnical Society
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• v.26 no.7
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• pp.135-145
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• 2010

Top Base Foundation (TBF) is widely used for the increment of bearing capacity and restraining settlement of foundations when the bearing capacity of ground is not enough. The design of bearing capacity obtained from exiting Japanese standard underestimates considerably what is compared with the observation values from the field measurement. Therefore, intensive model tests and site observation programs are carried out to establish more reasonable prediction technique and understanding of TBF in soft ground. In this study, 1/5 scale model tests are performed in order to investigate the behavior of TBF with various shapes in a laboratory. Also, about 100 sites measurement data are evaluated to investigate the field behavior of TBF in various ground conditions. Based on the results of the model tests and field measurement data, it was possible to introduce more reasonable bearing capacity equations of TBF considering N-value of soils, the effect of underground water and failure mechanisms.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.436-452
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• 2008

In this study, the settlement prediction method based on field monitoring data under preloading improvement with ramp loading is developed. Settlement behavior can be predicted with field monitored settlement throughout the entire preloading process including ramp loading followed by constant loading. The developed method is verified by comparing its predicted results with results from physical model tests and field monitoring data.

• Journal of Korea Association of Health Promotion
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• v.1 no.1
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• pp.7-8
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• 2003

The health screening and promotion is an emerging field of clinical preventiemedicine and is proved to be effective for reduction of diseaseprevalence, particularly life-style related diseases in aged population. However, the goal of perodic health screening can be achieved by a reliable health screening that largely depond on the quality of tests. Various tests including ultrasonography, endoscopy, CT and automated blood analyzers are used in health screening. Thesescreening tests are usually sensitive, but not specific to the presence of diseases. It meams the tests produce more false positive results, that demand eztra-expenses for the confirmation of disease. Promising screening tests should be sensitive as well as specific. However, it is not easy to maintain the quality of laboratory tests, because it is affected by various factors, such as instruments, reagents, laboratory methods and human factors. This review focuses on internal and external quality control of laboratory tests and quality management of health screening services to obtain reliable test results.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.11 no.1
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• pp.1-11
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• 2018

This paper provides field test results to confirm and compare the receiving characteristics of digital radio in various environments. HD Radio and DRM+ was used for the in-band method, while DAB/DAB+/T-DMB were used for the out-of-band method. To run field tests for digital radio, a transceiver test bed was constructed in a region in Korea selected as suitable for the testing, and indoor and outdoor reception tests were conducted by selecting 16 test points with different levels of multipath. Not only was the receivability tested at the test point, but ATT margin was also applied, in order to derive the minimum reception level. Through various analyses, the findings obtained through the field tests can aid in the setting of a standard for determining the method of digital radio transmission to ensure a smooth reception environment for consumers.

• Smart Structures and Systems
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• v.13 no.6
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• pp.993-1014
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• 2014

In civil engineering, revolving structures (RS) are a unique structural form applied in innovative architecture design. Such structures are able to revolve around themselves or along a certain track. However, few studies are dedicated to safety design or health monitoring of RS. In this paper, a wireless dynamic sensing system is developed for RS, and field tests toward a large revolving auditorium are conducted accordingly. At first, a wheel-rail problem is proposed: The internal force redistributes in RS, which is due to wheel-rail irregularity. Then the development of the sensing system for RS is presented. It includes system architecture, network organization, vibrating wire sensor (VWS) nodes and online remote control. To keep the sensor network identifiable during revolving, the addresses of sensor nodes are reassigned dynamically when RS position changes. At last, the system is mounted on a huge outdoor revolving auditorium. Considering the influence of the proposed problem, the RS of the auditorium has been designed conservatively. Two field tests are conducted via the sensing system. In the first test, 2000 people are invited to act as the live load. During the revolving process, data is collected from RS in three different load cases. The other test is the online monitoring for the auditorium during the official performances. In the end, the field-testing result verifies the existence of the wheel-rail problem. The result also indicates the dynamic sensing system is applicable and durable even while RS is rotating.

• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.4
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• pp.105-111
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• 2018

Institutional inertia anti-disaster standard was presented mainly on the upper surface, it is necessary to improve to the soil type standard and uplift the resistance standard greenhouse that are vulnerable to strong winds. In this study, we carried out a field test using the load control method in order to evaluate the uplift resistance of continuous foundation of greenhouse with different depths of the rafters. Institutional inertia anti-disaster standard of greenhouse foundation did not protect the greenhouse structure from the damages caused by strong winds and heavy snow. Therefore, field tests for behavior characteristics of continuous greenhouse foundation were carried out to ensure stable facility cultivation. The field test condition was evaluated using different embedded depth as follows: 30cm, 40cm, 50cm and spacing 50cm, 60cm, 70 cm. As a result of the uplift resistance field tests using the load control method, the minimum uplift resistance was found to be over 90kg and uplift resistance displacement was 9.4mm. Uplift resistance of the continuous greenhouse foundation was in the range of 90-180 kg according to embedded depth and spacing. Using the test condition, there was no constant trend in the uplift resistance.

• Proceedings of the Korean Geotechical Society Conference
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• 1997.10a
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• pp.19-36
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• 1997

This paper discusses the reduction and subsequent recovery and increase of shear strength of clay in the vicinity of soil-cement column. Laboratory and field tests were conducted to investigate the effects on surrounding clay during and after soil-cement column installation in soft Ariake clay. Discussions were made on the mechanism of strength changes of clay by considering the thixotropic recovery, reconsolidation effect, penetration of cement slurry and diffusion of exchangeable cations. On the basis of field and laboratory observations, 10 days after column installation, the decreased shear strength of surrounding clay during mixing was recovered and 30 days later, shear strength of surrounding clay increased 30% by average. Therefore, it is recommended that the increase of shear strength of clay can be taken into consideration in the bearing capacity and stability analysis of the composite ground.

• Journal of The Korean Society of Agricultural Engineers
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• v.52 no.4
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• pp.45-52
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• 2010

The purposes of this research are to analyze the internal settlement behavior of Concrete Faced Rockfill Dam (CFRD) typed 'D dam' and to evaluate the stability of the 'D dam' during dam construction using internal settlement measurements and results of numerical analysis. The field measurements were obtained during dam construction period. The numerical analysis was also carried out for the same construction period. The numerical analysis focused mainly on prediction of stress and displacement behavior of 'D dam' during dam construction stage using input parameters obtained from laboratory tests, i.e. large triaxial tests. The behavior of 'D dam' was evaluated to be stable from comparing the results of field measurements and numerical analysis. A simple empirical equation is also presented to predict final settlement at the completion of dam construction, using settlement measurement monitored during dam embankment.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.11
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• pp.1051-1058
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• 2012

The unified lateral control algorithm for automatic valet parking for various types of vehicles is presented and its feasibility is shown experimentally via field tests for the given parking scenario. First, a trajectory generation algorithm for forward driving and backward multi-step parking maneuvers is developed. Then, with consideration of different types of vehicles and operating conditions, a kinematic vehicle model is used and validated using field test data. Using the nonlinear vehicle model, the lateral controller is designed based on dynamic surface control. Finally the proposed lateral control law is validated via hardware-in-the-loop simulations for different types of vehicles and experimentally using a test vehicle through field tests.

• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.277-280
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• 1995

A new improved excitation control system for power plant synchronous generators has been developed by KEPRI(Korea Electric Power Research Institute). In this paper a description of the developed control system with detailed design concept is given. Field tests are conducted to show the system performance and to obtain the model parameters. Based on the measurement approached by field tests excitation model parameters supposing a mathmatical model is given can be determinded. This paper also proposes a algorithm of parameter estimation and identification in the synchronous Generator Excitation Control System.