• Structural Engineering and Mechanics
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• v.31 no.5
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• pp.507-526
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• 2009

Based on numerical and experimental methods, a systematic structural evaluation of a steel natatorium in service was carried out in detail in this paper. Planning of inspection tasks was proposed firstly according to some national codes in China in order to obtain the economic and reliable results. The field visual inspections and static computation were conducted in turn under in-service environmental conditions. Further a three-dimensional finite element model was developed according to its factual geometry properties obtained from the field inspection. An analytical modal analysis was performed to provide the analytical modal properties. The field vibration tests on the natatorium were conducted and then two different system identification methods were used to obtain the dynamic characteristics of the natatorium. A good correlation was achieved in results obtained from the two system identification methods and the finite element method (FEM). The numerical and experimental results demonstrated that the main structure of the natatorium in its present status is safe and it still satisfies the demand of the national codes in China. But the roof system such as purlines and skeletons must be removed and rebuilt completely. Moreover the system identification results showed that field vibration test is sufficient to identify the reliable dynamic properties of the natatorium. The constructive suggestion on structural evaluation of the natatorium is that periodic assessment work must be maintained to ensure the natatorium's safety in the future.

• Journal of Korean Library and Information Science Society
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• v.38 no.4
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• pp.441-462
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• 2007

As country try expand R&D investment and enhance its efficiency to improve the national competitiveness, research is needed to conduct qualitative enhancement and derive progressive future strategy in relation to the academic information distribution project in scientific technology field. In this study, BSC-based performance indicators were applied to an institute that is the representative of domestic academic information distribution institutes in the field of scientific technology to evaluate project performance, and then to analyze portfolio of using such evaluation results. As for the items of evaluation for the performance indicators of academic information distribution project in the scientific technology field, 12 items that includes information resource quality, information service quality, user satisfaction and economically useful value of academic information from four(4) viewpoints such as information resource, information service, user and economic viewpoints. In the portfolio analysis, it was conducted by performance indicators and by elements of the individual performance indicators as well. Based on the results of performance evaluation and portfolio analysis, the improvement method by viewpoints on academic information distribution project of an institute was suggested.

• Journal of Embryo Transfer
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• v.20 no.2
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• pp.157-162
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• 2005

To find out the possible inefficiencies of artificial inseminators at rectovaginal insemination in cows, inseminators' skill were evaluated by controlling the semen thawing procedure adopted and by using the technique of dye deposition in the genital tract of slaughtered cows. This was followed by refreshment training for the inseminators. Thirty seven artificial insemination technicians regularly working in the government, cooperative and NGO (Non Government Organization) artificial insemination programmes at different places of Bangladesh were included in the study. Individual technicians were asked to thaw a semen straw and deposit dye in the genital tract of slaughtered cows following the procedures they would have adopted in their actual practices of insemination. The time and water temperature adopted by technicians were recorded and genital tract after sham artificial insemination was dissected to determine the site of dye deposition. Then, the inseminators took part in a three days intensive training program. The training program was ended up with the same tests for thawing frozen semen straw and dye deposition in the genital tract of slaughtered cows. At pre training evaluation, only $25\%\;and\;72\%\;(n=36)$ inseminators adopted co..ect thawing time and temperature, respectively. At post training evaluation, all inseminators thawed semen straws for proper time and temperature. At pretraining evaluation, $21(57\%),\;11 (30\%)\;and\;3(8\%)$ inseminators deposited dye at the body of uterus, in the vagina or in cervix, and into the horn of uterus, respectively. In $2(5\%)$ cases dye did not pass into the genital tract, instead back flowed through the space between the barrel of insemination gun and sheath. At post training evaluation, all inseminators successfully deposited dye in the body of uterus. Frequent evaluation of inseminators' skill and subsequent training would help improvement of the artificial insemination technicians' skill.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.2
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• pp.103-107
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• 2000

The viviparity of 28 rice varieties was tested at 25 days after heading(DAH), 35DAH, and 45DAH in the laboratory and field condition for 12 days. The incubation temperature was 20/l$0^{\circ}C$ (day/night), 25/15$^{\circ}$C$ and 30/20$^{\circ}$C$ in the laboratory test, and under field water conditions in the field test. The biggest varietal difference of viviparity was found in the laboratory test when examined at 45DAH with the 6-day incubation under 25/15$^{\circ}$C$ . At this conditions the mean viviparous ratio was 32.1 % with the range of 53.9 and the variance of 259.5. In the field test, the significant varietal difference in the viviparity was also found in the lodging treatment at 45 DAH for 6 days. Correlation coefficient analysis between the field and laboratory tests was highly significant from 4 days after incubation at 45 DAH and after 6-day incubation at 35 DAH, and correlation coefficient was higher as incubation days in the laboratory and submerged days under field water became longer. Considering the correlation between the field and laboratory tests, varietal difference of viviparity and convenience of testing, the laboratory test at 45 DAH for 6-day incubation under 25/15$^{\circ}$C$ was the most efficient evaluation method for the viviparity of rice cultivar.

• Progress in Superconductivity and Cryogenics
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• v.14 no.4
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• pp.41-45
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• 2012

An HTS (high temperature superconducting) coil without insulation has been investigated since a metallic insulation was suggested in the mid-1980s. The advantage of an insulationless HTS pancake coil is that it is more stable than an insulated HTS pancake coil. This paper focuses on the various characteristics of the insulationless HTS pancake coil related with stability, especially under the external magnetic field. Because HTS pancake coil may be influenced by the external magnetic field in a real operational environment of electrical devices. First, charge-discharge test was performed for the characteristics evaluation of the insulationless HTS pancake coil as compared with insulated HTS pancake coil in liquid nitrogen at 77 K. Based on the experiment results, characteristics evaluation of the insulationless HTS pancake coil was implemented under the external magnetic field. In order to carry out the experiment, we have fabricated a cylindrical solenoid coil to apply the magnetic field. The various characteristics of the insulationless HTS pancake coil were evaluated for charge-discharge and over-current conditions. This paper proves that the insulationless HTS pancake coil is more stable than the insulated HTS pancake under the external magnetic field.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.7
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• pp.1236-1240
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• 2007

In order to evaluate if the high-Tc superconducting(HTS) power cable is operating stably, the characteristics of the HTS power cable should be found out. The properties of HTS tapes by measuring the voltage with respect to the current can be archived. But, the HTS power cable is different from the case of HTS tapes. This method is invalid because of the electromagnetic fields caused by other HTS tapes. In this paper, the stability evaluation of the HTS cable was performed by the following procedure. First, the voltage-current characteristics of HTS tape were measured and the electromagnetic field distributions of the HTS power cable with the external magnetic field were analyzed. Second, the losses of the HTS power cable were calculated using the result of the measurement and the analysis. Finally, the stable operation of the HTS power cable was evaluated on the basis of the losses of the superconducting cable.

• Journal of Applied Reliability
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• v.13 no.4
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• pp.241-252
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• 2013

Because of financial and safety concerns, there are needs for more accurate prediction of bridge behavior. Underestimation of the bridge load carrying capacity can have serious economic consequences, as deficient bridges must be repaired or rehabilitated. Therefore, the knowledge of the actual bridge behavior under live load may lead to a more realistic calculation of the load carrying capacity and eventually this may allow for more bridges to remain in service with or without minor repairs. The presented research is focused on the reliability evaluation of the actual load carrying capacity of existing bridges based on the field testing. Seventeen existing bridges were tested under truck load to confirm their adequacy of reliability. The actual response of existing bridge structures under live load is measured. Reliability analysis is performed on the selected representative bridges designed in accordance with AASHTO codes for bridge component (girder). Bridges are first evaluated based on the code specified values and design resistance. However, after the field testing program, it is possible to apply the experimental results into the bridge reliability evaluation procedures. Therefore, the actual response of bridge structures, including unintentional composite action, partial fixity of supports, and contribution of nonstructural members are considered in the bridge reliability evaluation. The girder distribution factors obtained from the tests are also applied in the reliability calculation. The results indicate that the reliability indices of selected bridges can be significantly increased by reducing uncertainties without sacrificing the safety of structures, by including the result of field measurement data into calculation.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.803-812
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• 2008

Along with the increasing demand for automatic and mechanical tunnel excavation methods in Korea, the Tunnel Boring Machine (TBM) method of tunnel excavation has become increasingly popular. However, in spite of this rising demand, few studies have been performed on the TBM method, in Korea. For this reason, this study focused on evaluation of the applicability of TBM performance prediction models based on field data in order to contribute to the basic and essential parts of TBM designation and the TBM method of tunnel excavation in Korea. These rock properties can be defined as the mechanical and physical factors of rock that have an influence on a disc cutter's ability to cut rock, and provide information for the evaluation of the applicability of field data. Based on outcomes from these tests, applicability of the prediction model was evaluated and the predicted performance of a TBM was compared with real field data obtained from four different TBM construction sites in Korea.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.1251-1258
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• 2006

Field evaluation of new scour countermeasure using geobag and aggregate is performed to prepare for the basis of design and construction standard in Korea. Polyester non-woven geotextile is determined as a geobag material and tire cord is used to sew up the geobag which contain aggregate. Hwasang-gyo(bridge) is selected as a pilot test site through office review and field investigation. According to the design flood of Hwasang-gyo(bridge), the size and volume of geobag are calculated and construction area and required number of geobags are computed by considering the specification of the pier and foundation of the bridge. After construction, scour depth around geobag construction area is measured and the stability of geobag is ascertained by using pole and digital camera.

• Smart Structures and Systems
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• v.4 no.4
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• pp.449-464
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• 2008

An array based, outward monitoring, ultrasonic guided wave based SHM technique using a single transmitter and multiple receivers (STMR), with a small footprint is discussed here. The previous implementation of such SHM arrays used a phase-reconstruction algorithm (that is similar to the beam-steering algorithm) for the imaging of reflectors. These algorithms were found to have a limitation during the imaging of defects/reflectors that are present in the "near-field" of the array. Here, the "near-field" is defined to be approximately 3-4 times the diameter of the compact array. This limitation is caused by approximations in the beam-steering reconstruction algorithm. In this paper, a migration-based reconstruction algorithm, with dispersion correction in the frequency domain, is discussed. Simulation and experimental studies are used to demonstrate that this algorithm improves the reconstruction in the "near-field" without decreasing the ability to reconstruct defects in the "far-field" in both isotropic and anisotropic plates.