• Journal of The Korean Association For Science Education
• /
• v.43 no.1
• /
• pp.29-36
• /
• 2023

This study investigates the effects of the operation of science activity program on scientific literacy focusing on science cultural literacy and core competencies for pre-service teachers. 255 pre-service teachers of K University participated, and the effects of the program were examined through a paired-sample t-test with one group pretest-posttest design for science cultural literacy. Only the post-test was conducted on core competency growth perception, and differences in growth perceptions by competency were compared using ANOVA. As a result of the study, the average of pre-service teachers was higher than the pre-test for science culture literacy, and this difference was statistically significant (p<.05). In the core competency growth perception, 70.6% of pre-service teachers reported growth in scientific communication ability, and as a result of the post-hoc test using LSD, it shows statistically significant growth compared to other competencies (p<.05). Through this, it was possible to confirm the educational value of the science activity program as a way to develop pre-service teachers' scientific literacy.

• Journal of Aerospace System Engineering
• /
• v.18 no.4
• /
• pp.109-116
• /
• 2024

The validity of the analysis results was confirmed based on the insulation test results, and the vaporization mass generated in the common bulkhead was calculated to evaluate the common bulkhead propellant tank's insulation performance. The analysis results were validated by comparing the transient heat transfer analysis with the insulation test results. A transient heat transfer analysis was subsequently conducted on the common bulkhead propellant tank, considering the internal heat conduction in the propellant tank and natural convection heat transfer due to the outside air. This analysis extracted the heat flux generated in the common bulkhead and quantified the vaporization mass, a key indicator of insulation performance. Consequently, the vaporization mass was calculated at 0.09 kg, below the insulation design standard of 0.12 kg for the common bulkhead propellant tank, confirming it meets the insulation performance standard.

• Journal of the Korea Concrete Institute
• /
• v.17 no.4 s.88
• /
• pp.603-611
• /
• 2005

For the establishment of rational seismic design code for RC (reinforced concrete) bridge pier, this paper has analyzed the seismic code of RC bridge pier specified in )veil-known codes such as KHBDS (Korea Highway Bridge Design Specification), AASHTO Standard, ATC-32, Eurocode 8, NZS 3101, etc. So as to secure aseismic ductility of RC pier, transverse confinement steel ratios of those codes have been examined together with other design parameters such as strength of concrete and reinforcing steel, axial force ratio, aspect ratio, longitudinal steel ratio, etc. However, there has been arisen a doubt for the validity of those parameters. Thus, the objective of this study is to quantitatively evaluate the validity of design parameter of each code on the experimental seismic ductility for about 80 test specimens. It was concluded from this study that the axial force ratio is a dominant factor for the seismic displacement ductility. Therefore, it Is desirable that the axial force ratio be further taken into account in the corresponding seismic design formula of RC bridge pier in current KHBDS.

• Journal of the Korean Home Economics Association
• /
• v.44 no.9
• /
• pp.31-39
• /
• 2006

This study was conducted to reproduce the two-piece sleeve pattern of the ladies' jacket of the 1890's for Korean women of the twenties who have the standard body type and the average size. Fourteen two-piece sleeve patterns of the ladies 'jacket of the 1890's were collected and drawn to actual size. The length and width proportion of the upper-sleeve and under-sleeve pattern of the ladies' jacket of the 1890's were similar to the two-piece sleeve pattern of jacket which we see now. The elbow line of the two-piece sleeve pattern of the ladies' jacket of the 1890's was lower than the two-piece sleeve of jacket of today. The cap of the sleeve of the ladies' jacket of the 1890's was gathered and this gave volume to the upper part of sleeve but the lower part of the sleeve was tight. The study pattern of two-piece sleeve pattern which had the characteristics of the sleeve pattern of the ladies' jacket of the 1890's was designed like for Korean women of the twenties who have the standard body type and the average size through modifications based on the evaluation of dressing on two occasions. The study pattern was evaluated to have the silhouette of the sleeve of the ladies' jacket of the 1890's and to fit Korean women of the twenties who have the standard body type and the average size with the sensory test.

• Journal of the Korean Geosynthetics Society
• /
• v.11 no.4
• /
• pp.37-44
• /
• 2012

This paper describes large scale pullout test results, in order to evaluate extensibility effect of strip-type reinforcement. The same test for ribbed steel strip reinforcement also is conducted to compare the friction resistance reinforcements' evaluation results. The pullout resistance of the ribbed steel strip reinforcement, which has a small cross sectional areas, was better than the friction resistance reinforcements' due to the bearing (passive) resistance. In case of friction resistance reinforcements, the pullout resistance of extensible reinforcement was better than inextensible reinforcement' even though they have a similar cross sectional areas.

• 한국신재생에너지학회:학술대회논문집
• /
• 2010.11a
• /
• pp.129.2-129.2
• /
• 2010

As a part of the government renewable energy policy, KOWEPO is constructing 300MW IGCC plant in Taean. IGCC plant consists of gasification block, air separation unit and power block, which performance test is separately conducted. Overall performance test for IGCC plant is peformed to comply with ASME PTC 46. Major factors affected on the overall efficiency for IGCC plant are external conditions, each block performance(gasification, ASU, power block), water/steam integration and air integration. Performance parameters of IGCC plant are cold gas efficiency, oxygen consumption, sensible heat recovery of syngas cooler for gasification block and purity of oxygen, flow amount of oxygen and nitrogen, power consumption for air separation unit and steam/water integration among the each block. The gas turbine capacity applied to the IGCC plant is 20 percent higher than NGCC gas turbine due to the low caloric heating value of syngas, therefor it is possible to utilize air integration between gas turbine and air separation unit to improve overall efficiency of the IGCC plant and there is a little impact on the ambient condition. It is very important to optimize the air integration design with consideration to the optimized integration ratio and the reliable operation. Optimized steam/water integration between power block and gasification block can improve overall efficiency of IGCC plant where the optimized heat recovery from gasification block should be considered. Finally, It is possibile to achieve the target efficiency above 42 percent(HHV, Net) for 300MW Taean IGCC plant by optimized design and integration.

• Physical Therapy Rehabilitation Science
• /
• v.2 no.2
• /
• pp.115-118
• /
• 2013

Objective: Whole body vibration training is a relatively new approach for enhancement of muscle strength, physical performance, and balance. The aim of this study was to assess the effect of unilateral whole body vibration training. Design: One group pretest-posttest design. Methods: Sixteen healthy, physically active volunteers participated in this study. Whole body vibration was applied with a frequency of 20 Hz and an amplitude of 3 mm for 3 minutes. Muscle performance and static balance were assessed before and after unilateral whole body vibration training. One leg standing broad jump test was measured to determine muscle performance which is closely linked to lower extremity muscle function. The good balance system was used in evaluation static balance. All test were measured 3 times and the average value was analyzed. Results: Jumping length was significantly improved by 0.11m in all participants after intervention (p<0.05). Among static parameters, significant results were observed where in the eyes opened condition, X-speed (medial-lateral sway) changed from 4.20 mm/s to 4.95 mm/s, Y-speed (anterior-posterior sway) changed from 5.77 mm/s to 6.54 mm/s and velocity moment changed from $12.77mm^2/s$ to $13.57mm^2/s$ (p<0.05). In the eyes closed condition, X-speed changed from 4.34 mm/s to 4.85 mm/s, Y-speed changed from 7.84 mm/s to 8.16 mm/s and velocity moment changed from $16.03mm^2/s$ to $16.11mm^2/s$ (p<0.05). Conclusions: Immediate unilateral whole body vibration improved muscle performance but impaired static balance in young adults.

• Journal of the Korean Geotechnical Society
• /
• v.31 no.2
• /
• pp.65-73
• /
• 2015

The bank revetment work which is conducted on the slope of river bank to protect against flowing water as a geotechnical structure has been applied as an average value of critical tractive force based on domestic and international standard design. Currently, an appropriate evaluation is needed for the hydraulic stability and geotechnical behavior analysis of bank revetments because of the effects of climate change and ambiguous design criterion. This study has compared the critical tractive forces of soil improvement material and conventional materials used for the bank revetment work. Through various experiments, the shear strength of mixtures with soil improvement material was investigated by curing time and mixture ratio. It was found that the critical tractive force of the mixture obtained from a scour test is suitable to the reinforcement of the slope of river bank which has problems such as seepage erosion and scour.

• Journal of the Korean Geotechnical Society
• /
• v.18 no.1
• /
• pp.79-89
• /
• 2002

Various geosynthetics used as liners or protection layers are installed in the solid waste landfills. The interface shear strength between geosynthetics installed at the slope of the landfill is a very important variable for the safe design of the bottom and cover systems in the solid waste landfills. The interface shear strength between Geomembrane and Geotexile is estimated by a large direct shear test in this study, The effects of normal stress, water existing between geosynthetics and surface condition of Geomembrae, i.e. smooth or textured, were investigated. The test results show that the effect varied depending on the level of normal stress and the type of geosynthetic combinations. The shear strength was evaluated by the Mohr-Coulomb failure criterion in this research. The shear strength parameters obtained from tests considering the site specific conditions such as normal stress, dry or wet, and surface condition of geosynthetic should be applied to the design of geosynthetics installed at the slope of the landfill to construct a safe solid waste landfill.

• Archives of design research
• /
• v.18 no.2 s.60
• /
• pp.345-354
• /
• 2005

From the 20th century, as international trade increases with the development of transportation and industries, a standard pictorial language to facilitate exchanges with others in different countries became necessary. However, it is not easy to have a full agreement on a standard pictorial language among different cultures. Therefore, the evaluation of standard pictograms has been the main discussion issue of the 150 since the organization's establishment in 1947. Although the 150 has a test method, 1509186, the participating countries do not follow the test because it does not reflect individual seeing mechanism for decoding pictogram which varies with his/her own experience. This study focuses on the theory of graphic symbol and seeing mechanism, and suggests what should be taken into account in the standardization process. In Chapter 2, the study investigates whether there be any cultural shock as we live in the net culture, and defines what reality is from a digital aesthetics view. What should be studied further is also presented, and a new method for revised international standard by means of analyzing seeing mechanism of decoding pictogram is suggested.