• Geotechnical Engineering
• /
• v.13 no.5
• /
• pp.35-44
• /
• 1997

A finite element computer program is developed for the specific analysis of earth retaining structures in urban excavation. Unlike the existing multi -purpose FEM programs, the newly developed program (EM) consists of very simple and easy data processing system for the urban excavation. A non-linear material model(GDHM, Generalized Decoupled Hyperbolic Models is deviloped and implemented in the program EM. The results of large scale model tests for earth retaining structures are used for the vertification of EM along whit GDHM, and the results were satisfactory, but it was found that the program EM needs minor modification for the improvement of its accuracy.

• Journal of the Korean Society of Safety
• /
• v.26 no.2
• /
• pp.62-69
• /
• 2011

This paper presents a new simple two-dimensional frame finite element able to accurately estimate the load-carrying capacity of reinforced concrete beams flexurally strengthened externally bonded fiber reinforced polymer (FRP) strips and plates. The proposed analysis model considers distributed plasticity with layer-discretization of the cross-sections and the bond-slip behavior of epoxy layer. The proposed model is used to predict the load-carrying capacity and the applied load-midspan deflection response of RC beams subjected to bending loading. Numerical simulations and experimental measurements are compared based on numerous tests available in the literature and published by different authors. The numerically simulated response agree remarkably well with the corresponding experimental results. Thus, the proposed model is suitable for efficient and accurate modeling and analysis of flexural strengthening of RC beams with externally bonded FRP sheets/plates and for practical use in design-oriented parametric studies.

• Asian-Australasian Journal of Animal Sciences
• /
• v.27 no.10
• /
• pp.1406-1410
• /
• 2014

Age at first calving is an important trait for achieving earlier reproductive performance. To detect quantitative trait loci (QTL) for reproductive traits, a genome wide association study was conducted on the 96 Hanwoo cows that were born between 2008 and 2010 from 13 sires in a local farm (Juk-Am Hanwoo farm, Suncheon, Korea) and genotyped with the Illumina 50K bovine single nucleotide polymorphism (SNP) chips. Phenotypes were regressed on additive and dominance effects for each SNP using a simple linear regression model after the effects of birth-year-month and polygenes were considered. A forward regression procedure was applied to determine the best set of SNPs for age at first calving. A total of 15 QTL were detected at the comparison-wise 0.001 level. Two QTL with strong statistical evidence were found at 128.9 Mb and 111.1 Mb on bovine chromosomes (BTA) 2 and 7, respectively, each of which accounted for 22% of the phenotypic variance. Also, five significant SNPs were detected on BTAs 10, 16, 20, 26, and 29. Multiple QTL were found on BTAs 1, 2, 7, and 14. The significant QTLs may be applied via marker assisted selection to increase rate of genetic gain for the trait, after validation tests in other Hanwoo cow populations.

• Journal of Advanced Marine Engineering and Technology
• /
• v.12 no.3
• /
• pp.57-67
• /
• 1988

Although handicapped by the inability to bridge the size gap between small laboratory sample and large engineering component, the V charpy test sample method does possess certain advantages, such as each of preparation, simplicity of test method, speed, low cost in test machinery, and low cost per test. On the other hand, the COD test method does posses advantages, which reduce the size gap between the laboratory sample and actual engineering component. Consequently, the correlation between V charpy absorbed energy and the critical COD value is required for estimating critical COD value from the simple V charpy test results. In this paper, the high tensile strength steel AH36 plate specimens having a single edge cracked notch were investigated to find out the correlation between V charpy absorbed energy and critical COD value in the welded parts under such various welding methods as shielded metal arc welding, the submerged arc welding and the electro gas welding by means of V charpy impact test and static 3-point bending test. Main results obtained are as follow ; 1. The relationships between V charpy absorbed energy Wc' and critical COD value ($\delta_c$)show; $\delta_c$=0.0065 Wc'+0.1906. 2. Ductile- brittle transition behaviours can be estimated by means of fracture appearance and general yielding behaviours. 3. The V charpy absorbed energy of SMAW is higher than that of SAW, EGW and similar relationships are obtained in the COD tests.

• Structural Engineering and Mechanics
• /
• v.65 no.2
• /
• pp.183-190
• /
• 2018

The prestressed concrete (PSC) technology that was first developed by Freyssinet has significantly improved over the past century in terms of materials and structural design in order to build longer, slender, and more economic structures. The application of prestressing method in structures, which is determined by the pre-tension or post-tension processes, is also affected by the surrounding conditions such as the construction site, workforce skills, and local transportation regulations. This study proposes a prestressed concrete girder design based on a hybrid segment concept. The adopted approach combines both pre-tension and post-tension methods along a simple span bridge girder. The girder was designed using newly developed 2400 MPa PS strands and 60 MPa high-strength concrete. The new concept and high strength materials allowed longer span, lower girder depth, less materials, and slender design without affecting the lateral stability of the girder. In order to validate the applicability of the proposed hybrid prestressed segments girder, a full-scale 35 m girder was fabricated, and experimental tests were performed under various fatigue and static loading conditions. The experimental results confirmed the feasibility of the proposed long-span girder as its performance meets the railway girder standards. In addition, the comparison between the measured load-displacement curve and the simulation results indicate that simulation analysis can predict the behavior of hybrid segments girders.

• Korean Medical Education Review
• /
• v.16 no.1
• /
• pp.11-15
• /
• 2014

A number of medical schools in Korea have been using computer-based testing (CBT) for evaluating their students' scientific and/or clinical performance since the early 1990s. Introducing CBT to medical education would have several advantages: first, presenting figures and audio-video files of clinical content is simple with CBT, making it possible to evaluate medical students' competency with navigating more realistic clinical situations at minimum cost; second, CBT enables automatic item analysis and score reporting. To establish CBT, constructing an item bank with item parameters such as difficulty or discriminating parameters will be needed. To select more psychometrically sound items, analysis of the items according to item response theory is necessary. CBT has already been introduced in high stakes tests like the United States Medical Licensing Examination and the Medical Council of Canada Qualifying Examination. The National Health Personnel Examination Board in Korea is also planning to introduce a CBT-based version of the National Medical Examination soon. Thus all medical schools in Korea will need to introduce CBT and construct item banks to prepare their students for their licensing examinations and to measure the students' competency more accurately.

• Journal of Korea Multimedia Society
• /
• v.16 no.4
• /
• pp.520-528
• /
• 2013

Makeup simulation is a tool that tests various makeup methods on a virtual digital face using input and display devices. Although several simulation systems supporting various makeup styles have been recently developed, most systems have many limitations on realistic skin representations because they use 2D facial images. We develope a realistic makeup simulation method which can control skin reflectance and roughness parameters. The method allows a user to simulate makeup applications while changing skin parameters using high-resolution facial data acquired by 3D scanners. Besides we use a point-based shape representation which enables simple and flexible 3D rendering, and provide a more realistic makeup simulation by applying different skin parameters on each part of the face.

• Nutrition Research and Practice
• /
• v.1 no.3
• /
• pp.218-223
• /
• 2007

This study investigated: 1) what weight-related behaviors college students practiced; 2) if the behaviors were performed for weight-related reasons; and 3) whether the behavioral practices differed by gender, race, and body weight status. This cross-sectional study used a questionnaire to collect information from a non-probability sample of undergraduate students (n=379; 48% men) recruited from large introductory psychology classes. Chi-square tests were conducted to examine simple comparisons, and multiple logistic regression analyses assessed differences. Male students reported adopting significantly fewer weight-related behaviors than females. Most frequently males increased exercise (69.2%), increased fruit and vegetable consumption (50%), skipped meals (46%), cut out sweets and junk foods (40%), and cut out between-meal snacks (35%). Female students most frequently increased exercise (67.4%), skipped meals (63%), increased fruit and vegetable consumption (62%), reduced the amount of food eaten (60%), and cut out between-meal snacks (51%). Negative behaviors were engaged in by only a few participants. Weight-related reasons were a significant factor for weight-related behavior adoption. Multiple logistic regression analyses showed that gender was consistently and significantly associated with the adoption of weight-related behaviors, while race and weight status were less consistently associated. Findings of this study will be helpful to dietitians who counsel college students. Results of this study may support effects to bring more comprehensive behaviorally-focused health md nutrition interventions to college campuses.

• Journal of the Korean School Mathematics Society
• /
• v.2 no.1
• /
• pp.43-53
• /
• 1999

Two (second-grade) classes of Yu-song middle school were chosen to research the effect of the visualization in the learning of probability calculation at a middle school. One class, as an experiment class, was taught the probability calculation of probability unit by the visualization learning and the other, as a controlled class, was taught it by the traditional lecture, and then through the writing tests there was a verification on the effect of right after test and the delaying test after 3 weeks to examine the learning effect of high- and low-level groups. It was difficult for the students to visualize the problems of the probability calculation, but I suggested simple models to the students and helped them to learn meaningfully. As a result of this study, there showed statistically significant difference in high-level group in the right after test.(P< .05) In the delaying test after 3 weeks, there also showed statistically significant marks only in high-level group.(P< .05) The visualization in the learning of probability calculation took more affirmative effect in the experiment class than the comparative class only in high-level group. The students in low-level group has difficulties in the visualization activities, but all the students in high-and low-level group thought the visualization was a great help to them in learning probability calculation.

• 보존과학연구
• /
• s.30
• /
• pp.47-61
• /
• 2009

Cultural heritages are affected by various environmental factors. Main factors are temperature, humidity, light and indoor air pollutants such as ozone, nitrogen oxides. Especially humidity condition is very important. Low humidity condition can cause contraction and high humidity condition can lead to growth of microorganism. This study is conducted to appraise an applicability of the Humidity Indicator which is one of the simple method for humidity control. The Humidity Indicator shows the humidity conditions through color change. Therefore, photometer was used to correctly measure the color change of Humidity Indicator. As a result of lab test, Humidity Indicators was stabilized after one hour from en exposure in a certain humidity condition and the indicators indicated clear correlations between color changes of Humidity Indicators and humidity conditions. Some Humidity Indicators which had been selected through the lab tests were applied to preservation facilities of cultural heritages and the indicators indicated closed correlations with humidity conditions in indoor of facilities.