• Nuclear Engineering and Technology
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• v.50 no.8
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• pp.1412-1420
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• 2018

An experiment was performed using the large-scale test facility (LSTF), which simulated a 1% vessel upper head small-break loss-of-coolant accident with an accident management (AM) measure under an assumption of total-failure of high-pressure injection (HPI) system in a pressurized water reactor (PWR). In the LSTF test, liquid level in the upper head affected break flow rate. Coolant was manually injected from the HPI system into cold legs as the AM measure when the maximum core exit temperature reached 623 K. The cladding surface temperature largely increased due to late and slow response of the core exit thermocouples. The AM measure was confirmed to be effective for the core cooling. The RELAP5/MOD3.3 code indicated insufficient prediction of primary coolant distribution. The author conducted uncertainty analysis for the LSTF test employing created phenomena identification and ranking table for each component. The author clarified that peak cladding temperature was largely dependent on the combination of multiple uncertain parameters within the defined uncertain ranges.

• Korean Journal of Agricultural Science
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• v.40 no.3
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• pp.243-252
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• 2013

This study was carried out to investigate safety evaluation of agricultural reservoirs due to raising the embankment. The seepage analysis and large-scale model test were performed to compare and analyze the pore water pressure(PWP), leakage quantity, settlement and piping phenomenon in the inclined core type and the vertical core type embankments. The PWP after raising the embankment showed smaller than before raising the embankment and the stability for piping after raising the embankment. The allowable seepage quantity and the allowable leakage for the steady state and transient conditions is within the range of safe management standard. After raising the embankment in the inclined core, there was no infiltration by leakage. For the vertical core, the PWP showed a large change by faster infiltration of pore water than in the inclined core. In a rapid drawdown, inclined core was remained stable but the vertical core showed a large change in PWP. Settlement after raising the embankment showed larger amounts of settlement than before raising the embankment. The leakage quantity before raising the embankment and the inclined core type showed no leakage. From the result, an instrument system that can accurately estimate a change of PWP shall be established for the rational maintenance and stabilization of raising the embankment for agricultural reservoirs.

• Journal of the Korea Society of Computer and Information
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• v.24 no.1
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• pp.197-206
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• 2019

The purpose of this study is to develop and validate a model for diagnosing core competencies at the higher education level. Based on literature reviews, a potential model for core competencies at university was suggested. A tool for validating the model was composed of 24 items, which were delivered to 226 professors and administrative staffs, 730 students, and 134 graduates & external industrial experts. Five constructs (core competencies) were extracted from the data collected among professors and administrative staff responding to the importance of the items. The results of importance and performance surveys on core competencies with students were respectively 3.28 to 3.66 and 2.68 to 3.28 (4-point Likert scale). Statistical differences between importance level and performance level were found in all the sub-categories of core competencies. Borich priority determination formula and Locus for Focus Model were used for the determination of the priority of needs. Importance survey among graduates and external experts showed that the mean of each items ranged from 2.80 to 3.76 (4-point Likert scale). The overall results of the analyses suggest that the final model is appropriate for measuring the core competencies.

• Physical Therapy Rehabilitation Science
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• v.9 no.3
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• pp.131-139
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• 2020

Objective: The purpose of this study was to evaluate the effect of virtual reality (VR)-based core stabilization exercise on upper extremity function, postural control, and depression among persons with stroke with hemiplegia. Design: Randomized controlled trial. Methods: This study was conducted with the inclusion of 24 participants and were randomly assigned to either the VR-based trunk stability exercise group (n=12) or control group (n=12). The VR-based trunk stability exercise group performed core stabilization exercises in a VR environment for 30 minutes. Meanwhile, the control group conducted general core stabilization exercises for 30 minutes. The participants trained 3 times a week for 4 weeks. The manual functional test (MFT), Box and Block Test (BBT), Berg Balance Scale (BBS), Trunk Impairment Scale (TIS), the Geriatric Depression Scale (GDS) were used to assess all participants before and after the intervention. Results: The VR-based core stabilization exercise group had a significant improvement in upper extremity function (MFT, BBT) and postural control (BBS) compared with the control group (p<0.05). The VR-based core stabilization exercise showed a significant difference after intervention in the TIS and GDS scores (p<0.05), but they did not significantly differ between the two groups. Conclusions: The result showed that VR-based core stabilization exercise can be effective in improving upper extremity function and postural control among patients with stroke more than the sole application of general physical therapy.

• Journal of Engineering Education Research
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• v.24 no.5
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• pp.15-27
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• 2021

The purpose of this study was to develop an indicator of core competency of freshmen of an Institute of Science & Technology (IST). Through the document analysis and the expert survey, core competency indicators that include 5 core competencies and 15 sub-competencies (a total of 48 items) were developed. Then content validity was examined by experts in measurement and statistics and secondary education. Also, by using students' responses, reliability was tested with Cronbach's alpha and construct validity were tested through confirmatory factor analysis. Results suggest that the core competency indicator is reliable and valid in measuring core competencies of freshmen students in an Institute of Science & Technology. Discussions were provided in terms of improving student admission processes.

• International Journal of Naval Architecture and Ocean Engineering
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• v.10 no.3
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• pp.403-412
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• 2018

Medium-scale tests were conducted to measure and observe the strength and failure behavior of freshwater ice rubble. A custom box measuring $3.05m{\times}0.94m{\times}0.94m$, with Plexiglas walls was built so that failure mechanisms could be observed. Ice rubble beams of nominal thickness 50 cm were produced by placing randomly sized ice pieces into the box filled with water at its freezing temperature. After the specified consolidation time, ranging between 0.2 and 70.5 h, the ice rubble beam was deformed by pushing a platen vertically downwards though the center of the beam until failure. For consolidation times less than 4 h, the ice beam failed progressively and tended to fail by shearing on macroscopic scale. At times greater than 4 h the beam failed by bending. The change in failure behaviour has been attributed to the degree of bonding between ice blocks.

• Proceedings of the IEEK Conference
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• 2000.09a
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• pp.901-904
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• 2000

A direct authentication from gray-scale image, instead of the conventional multi-step preprocessing, is proposed using Gabor filter-based features from the gray-scale fingerprint around core point. The core point is located as a reference point for the translation invariant matching. And its principal symmetry axis is detected for the rotation invariant matching from its neighboring region centered at the core point. And then fingerprint is divided into non-overlapping blocks with respect to the core point and features are directly extracted form the blocked gray level fingerprint using Gabor filter. The proposed fingerprint authentication is based on the Euclidean distance between the corresponding Gabor features of the input and the template fingerprints. Experiments are conducted on 300${\times}$300 fingerprints obtained from a CMOS sensor with 500 dpi resolution, and the proposed method could lower the False Reject Rate(FRR) to 18.2% under False Acceptance Rate(FAR) of 0%.

• Journal of Magnetics
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• v.20 no.2
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• pp.138-147
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• 2015

The unique nano-scale inter-lamellar microstructure and unparalleled heat treatment process give our developed metal powder composite its outstanding magnetic property for power inductor & motor applications. Compared to the conventional polycrystalline Fe or amorphous Fe-Cr-Si-B alloys, our unique designed inter-lamellar microstructure strongly decreases the intra-particle eddy current loss at high frequencies by blocking the mutual eddy currents. The combination of optimum permeability, magnetic flux and extremely low core loss makes this powder composite suitable for high frequency applications well above 10 MHz. Moreover, it can be also possible to SMC core for high speed motor applications in order to increase the motor efficiency by decreasing the core loss.

• The Korean Journal of Emergency Medical Services
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• v.24 no.3
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• pp.65-78
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• 2020

Purpose: The purpose of the study was to investigate the core competency and educational needs of paramedic students in disaster management. Methods: A self-reported questionnaire was completed by 207 paramedic students between June 1 and October 29, 2017. The study instrument included disaster preparedness (15 items), disaster management core competency (26 items), disaster education needs (26 items). Data were analyzed using t-test, ANOVA, and Duncan's multiple range test using IBM SPSS 24.0. Results: The students reported that only 13% had experienced or witnessed disasters; however, 95.2% would be willing to help in the event of a disaster. Their disaster preparedness was 1.84 points on a 3-point scale. We did see differences in disaster preparedness by background: hospital practice (F=5.352, p=.001); fire-fighting practice (F=8.994, p=.000). The students had a core competency of disaster management at 3.25 points on a 5-point scale with differences depending on major satisfaction (F=3.760, p=.006). The level of student demands for disaster education was 4.29 points. Conclusion: If variety of educational environments are provided for disaster-related learning and training, the core competency of disaster management for paramedic students will improve. The students will be available as disaster management experts in various fields, even after graduation.

• Journal of architectural history
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• v.16 no.5
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• pp.55-66
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• 2007

Through analysing on construction cases of stupa built in A.D. 7,8th, I have researched about these : constructive methods of inner soil of stupa, spatial compositions, characteristics of structures, arrangements of inner soil and etc. And cases analysed are six ; Mireuksajiseoktap(stone pagoda of Mireuksa Temple site), Gameunsajisamcheumgseoktap(three storied stone pagoda of Gameunsa Temple site), Goseonsajisamcheungseoktap(three storied stone pagoda of Goseonsa Temple site), Wolseong nawolliocheungseoktap(five storied stone pagoda in Nawonri, Wolseong), Guksagokseoktap(three storied stone pagoda in Guksa valley), Giamgokseoktap(three storied stone pagoda in Giam valley). Additionally we researched about inner soil of Sacheonwangsaji tapji(basement of stone stupa site in Sacheonwang Temple site) to speculate on composition of Synthetically, the foundation could be divided as core space and outer space. ; the former as structural function and the latter as ornamental function. And the core area could be divided again as center column space and buffer space. The relationship between core spaces and its formation are as belows; First, according to the area of foundation and scale of stone pagoda, formations of core are differed. As the scale of stone pagoda goes bigger, and the area of foundation goes larger, the structure of stone pagoda comprised by center column type and layered-core which endure upper load independently. On the contrary, as the scale of stone pagoda goes smaller, and the area of foundation goes lesser, the structure of stone pagoda tend to use only center column to endure upper part. Second, spatial composition of core area is comprised as two spaces, one which endure upper load and buffer space which absorb side pressure and upper pressure. The buffer space tend to be used in case of those structures which could not endure side pressure or have lots of joint. In some cases, it was located below the cover stone of foundation and gained upper load. And in case that have not gained pressure from side stone, the buffer space are comprised by smalle stone or roof tile to get structural supplement.