• Wind and Structures
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• v.20 no.6
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• pp.719-737
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• 2015

Full scale measurement on the structural dynamic characteristics and Vortex-induced Vibrations (VIV) of a long-span suspension bridge with a central span of 1650 m were conducted. Different Finite Element (FE) modeling principles for the separated twin-box girder were compared and evaluated with the field vibration test results, and the double-spine model was determined to be the best simulation model, but certain modification still needs to be made which will affect the basic modeling parameters and the dynamic response prediction values of corresponding wind tunnel tests. Based on the FE modal analysis results, small-scaled and large-scaled sectional model tests were both carried out to investigate the VIV responses, and probable Reynolds Number effects or scale effect on VIV responses were presented. Based on the observed VIV modes in the field measurement, the VIV results obtained from sectional model tests were converted into those of the three-dimensional (3D) full-scale bridge and subsequently compared with field measurement results. It is indicated that the large-scaled sectional model test can probably provide a reasonable and effective prediction on VIV response.

• Animal Bioscience
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• v.36 no.10
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• pp.1568-1577
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• 2023

Objective: A study was conducted to determine the chemical composition of banana meal and rice bran from Australia or South-East Asia and test the hypothesis that there are no differences in rice bran produced in different countries, but there are differences between full-fat and defatted rice bran. Methods: Two sources of banana meal and 22 sources of rice bran (full-fat or defatted) from Australia or South-East Asia were used. All samples were analyzed for dry matter, gross energy, nitrogen, amino acids (AA), acid hydrolyzed ether extract (AEE), ash, minerals, total starch, insoluble dietary fiber, and soluble dietary fiber. Banana meal was also analyzed for sugars including glucose, fructose, maltose, sucrose, stachyose, and raffinose. Results: Chemical analysis demonstrated that banana meal from the Philippines is primarily composed of starch. Full-fat rice bran from Australia had greater (p<0.05) concentrations of AEE, lysine, and glycine than samples from the Philippines and Vietnam. Full-fat rice bran from Australia and Thailand had greater (p<0.05) concentrations of gross energy and most AA than rice bran from Vietnam. Full-fat rice bran from Australia had greater (p<0.05) concentrations of tryptophan and manganese than all other sources, but full-fat rice bran from the Philippines contained less (p<0.05) zinc than all other sources of rice bran. Gross energy, AEE, and copper were greater (p<0.05) in full-fat rice bran compared with defatted rice bran, but defatted rice bran contained more (p<0.05) crude protein, ash, insoluble dietary fiber, total dietary fiber, AA, and some minerals than full-fat rice bran. Conclusion: Banana meal is a high-energy source that can be used as an alternative ingredient in livestock diets. Full-fat rice bran from Australia and Thailand contained more concentrations of AEE and AA than samples from the Philippines or Vietnam. Full-fat rice bran had more gross energy and AEE than defatted rice bran, whereas defatted rice bran contained more crude protein, ash, and total dietary fiber.

• 전기의세계
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• v.13 no.4
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• pp.25-29
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• 1964

This paper shows that higher amplification can be achieved by applying load current on the internal feedback winding of the magnetic amplifier under test. Since the magnetic flux of the control winding and internal feedback winding saturate the core more fully, the permeability tends to zero and load current increases to the value more than that of ordinary magnetic amplifier without feedback.

• Journal of Korean Academy of Nursing
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• v.15 no.3
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• pp.62-73
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• 1985

The problems of growth & development due to maladjustment are gradually increasing while need for the treatment of children's diseases is decreasing. The level of developmental deficiency or delay correlates with neonatal birth weight and also with gestational age, i.e. degrees of prematurity. There-fore, developmental defects and potential risk factors' are more Common in premature infants than in full term infants. The purpose of this study is to define the difference in the growth at developmental status between premature and full term infants, and to define the relation between the developmental status and the physical growth during the first 3 years' Data were collected from January 10, 1985 to April 6, 1985 at 3 hospitals including St. Mary's Hospital, and through home visiting. The subjects of this study consisted of 79 Premature infants (G.A. <37wks. & B.W. <2.5kg) and 94 full term infants (G.A.≥37 wks. & B.W.≥2.5kg). The study method used was a questionnaire, anthropometric assessment and DDST for normative data of growth & development. The collected data were analyzed using descriptive statistics, chi-square test and t-test. The results of the study were as follows: Hypothesis: 1 : That the prematures will differ from the full term infants in the physical growth status during the first 3 years was partially supported (p＜0.02) : The prematures reached up the full term infants in the physical growth status in the first 6 months. And, the first hypothesis was supported (P<0.01) : There are more cases which is below‘the Korean children's physical. growth standards’in prematures than in full term infants. Hypothesis 2 : That the prematures will differ from the full term infants in the developmental status during the first 3 years was supported (P< 0.001)；‘Normal’developmental status due to DDST was less in prematures than in full term infants. And, the second hypothesis was Partially supported (P<0.02) : The developmental status of the pre-matures was different from that of the full term infants within the first 3 months by analysis of passed items in DDST, Hypothesis 3 : That the prematures' developmental status will relate to their physical growth during the first 3 years was supported (P<0.001) : If the prematures' developmental status is in delayed status, then, their physical growth status is also in delayed status. This study shows that the prematures differed significantly from the full term infants in the growth at developmental status during their infancy. This means that the nurse can foster the growth & development of the prematures by supportive care during their infancy. Further longitudinal study is needed to verify these findings for the environmental factors.

• Journal of Korean Tunnelling and Underground Space Association
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• v.10 no.2
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• pp.177-184
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• 2008

In this study, in order to reduce appeals regarding vibration and noise from blasts, the optimum delay-time of the electronic detonator, which can minimize blast vibration, is found through blast-waveform composition and blasting simulation, and we have developed the full-face Sequential Blasting Method based on the studies of damping properties of full-face section blasting. The optimum delay-time of the electronic detonator and Full-face Sequential Blasting Method using electronic detonator was applied to the Gyeongbu high-speed railway construction site to test the feasibility of this method.

• Korean Journal of Childcare and Education
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• v.9 no.5
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• pp.299-320
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• 2013

This research aims to develop and evaulate the effectiveness a group theraplay program for teachers than can boost full-day kindergarteners' ego resilence, peer competence and teacher-child relationships. A total of 14 children attending a full-day kindergarten located in Seoul were the subjects of this study. The experimental group consisted of 7 children exposed to 10 sessions of group theraplay for 50 minutes per session, held twice a week. The control group consisted of 7 children who did not receive any treatment. The teacher evaluated ego resilience, children's peer competence and student-teacher relationships to investigate two group's behavioral changes. Data analysis was done by performing the non-parametric Mann-Whitney test and Wilcoxon test after classifying and evaluating pre- and post-examinations of each group. The results of this research are as follows : The group theraplay program was found to be effective based on the study results of improving ego resilience and peer competence among full-day kindergartners and strengthening teacher-child relationships.

• Smart Structures and Systems
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• v.7 no.5
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• pp.379-392
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• 2011

This paper presents a multi-functional system, consisting of a magnetorheological (MR) damper and an electromagnetic induction (EMI) device, and its applications in stay cables. The proposed system is capable of offering multiple functions: (1) mitigating excessive vibrations of cables, (2) estimating cable tension, and (3) harvesting energy for wireless sensors used health monitoring of cable-stayed bridges. In the proposed system, the EMI device, consisting of permanent magnets and a solenoid coil, can converts vibration energy into electrical energy (i.e., induced emf); hence, it acts as an energy harvesting system. Moreover, the cable tension can be estimated by using the emf signals obtained from the EMI device. In addition, the MR damper, whose damping property is controlled by the harvested energy from the EMI device, can effectively reduce excessive cable vibrations. In this study, the multi-functionality of the proposed system is experimentally evaluated by conducting a shaking table test as well as a full-scale stay cable in a laboratory setting. In the shaking table experiment, the energy harvesting capability of the EMI device for wireless sensor nodes is investigated. The performance on the cable tension estimation and the vibration mitigation are evaluated using the full-scale cable test setup. The test results show that the proposed system can sufficiently generate and store the electricity for operating a wireless sensor node twice per day, significantly alleviate vibration of a stay cable (by providing about 20% larger damping compared to the passive optimal case), and estimate the cable tension accurately within a 2.5% error.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.11
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• pp.1144-1150
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• 2009

Appropriate vibration model is required to predict in advance the vibration level of a large vehicle which carries sensitive electronic/mechanical equipments and drives often on the unpaved and/or off-road conditions. Central tire inflation system(CTIS) is recently adopted to improve the mobile operation of military and bulletproof vehicles. In this paper, full vehicle model(FVM) having 11 degrees of freedom and equipped with CTIS has been developed for a large vehicle which has $8\times8$ wheels$\times$driving wheels. Usability of the developed model is validated via road tests for three different modes (i.e. highway, country, and mud/sand/snow modes) and for various velocity conditions. The developed FVM can be used to predict the vibration level of the large vehicle as well as to determine the driving velocity criterion for different road conditions.

• Bulletin of the Society of Naval Architects of Korea
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• v.8 no.1
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• pp.29-40
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• 1971

In order to study the problem on form factor of hull form, towing test of a full ship model was carried out for different initial trims under both full and half load conditions. The results were fully discussed on the mutual relations among initial trim, mean sinkage and trim change in run, and form factor. There exists optimum initial trim in regard to form factor. Mean sinkage and trim change in run can be expressed in a uninominal approximation in the form of $k_i{\cdot}{F_n}^{2.2}$. The coefficients of this approxmation are related linearly with the initial trim. Form factor changes according to Froude number. It is considered that the trim change in run is a main reason of the fact.

• Journal of the Optical Society of Korea
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• v.12 no.4
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• pp.355-358
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• 2008

In the current GPON market and standard, the line bit rate requirement is changing from 1.25 Gbps to 2.5 Gbps. We fabricate a 2.5 Gbps burst-mode receiver with commercially available blocks and optimize it with an APD bias control. A burst-mode measurement setup is made for the full compliance test with the GPON standard. The device meets the partially defined 2.5 Gbps specs in the current ITU G.984.2 standard, also, supports 1.25 Gbps specs for the coexistence issue in an access network. The full-compliant measurement values can be used as a guideline for fixing "for further study" specs in the current GPON standard at 2.5 Gbps.