• Structural Engineering and Mechanics
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• v.58 no.1
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• pp.1-19
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• 2016

Recently, the high-strength concrete is increasingly used in the construction of reinforced concrete structures due to its benefits, but this use is influenced negatively on the local ductility of structural elements. The objective of this study is the prediction of a new approach to evaluate the curvature ductility factor of high strength concrete beams according to Eurocode 2. After the presentation of the Constitutive laws of materials and the evaluation method of curvature ductility according to the Eurocode 2, we conduct a parametric study on the factors influencing the curvature ductility of inflected sections. The calibrating of the obtained results allows predicting a very simple approach for estimating the curvature ductility factor. The proposed formula allows to calculate the curvature ductility factor of high strength concrete beams directly according to the concrete strength $f_{ck}$, the yield strength of steel $f_{yk}$ and the ratio of tension and compression reinforcements ${\rho}$ and ${\rho}^{\prime}$ respectively, this proposed formula is validated by theoretical and experimental results of different researchers.

• Journal of Ginseng Research
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• v.19 no.2
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• pp.117-121
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• 1995

We studied the effects of ginsenoside-$Rg_1$ (G-$Rg_1$) extracted from Panax ginseng C.A. Meyer on $p56^{kk}$ kinase and cell proliferation in Jurkat T cells. $p56^{kk}$ was maximally activated within 5 min after the treatment of 16.7 $\mu\textrm{g}$/ml of G-$Rg_1$ increasing the activity by 1.2-2 times relative to untreated control, thereafter its activity was gradually decreased to the level of untreated control. The action of EGTA on the kinase was altered by the addition of G-$Rg_1$, accompanying the band shift of $p56^{kk}$ to $p60^{kk}$. In addition, G-$Rg_1$promoted cell proliferation in a concentration-dependent manner. These results suggest that G-$Rg_1$ may be involved in T cell receptor-CD3 (TCR) signaling via the activation of $p56^{kk}$ and the chance of cellular calcium concentration.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.6
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• pp.63-71
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• 2015

The objective of the present study is to investigate how elevated temperature ranging from $100^{\circ}C$ to $800^{\circ}C$ as well as room temperature affects the variation of mechanical properties of high strength concrete ($over\;f_{ck}=60MPa\;grade$). In this experiment, specimens were exposed for a period of $2^{\circ}C/min$ to temperatures of $20^{\circ}C$, $100^{\circ}C$, $200^{\circ}C$, $300^{\circ}C$ $400^{\circ}C$, $500^{\circ}C$, $600^{\circ}C$, $700^{\circ}C$ and $800^{\circ}C$, respectively. Accordingly, the study investigated the fire resistance performance of high strength concrete mixed with composite fibers which composed with hybrid fibers and steel fibers. After cooling down to ambient temperature, the following basic mechanical properties were then evaluated and compared with reference values obtained prior to thermal exposure: (i) compressive strength in room temperature; (ii) residual compressive strength; (iii) Poisson's ratio; (iv) weight change; (v) SEM analysis & XRD analysis In addition, XRD and SEM Images analyses were performed to investigate chemical and physical characteristics of high strength concrete with composite fibers according to high temperature.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.18
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• pp.8293-8298
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• 2016

Background: Urinary stones are known predisposing factors for upper urinary tract carcinoma (UUTC) which are commonly detected at advanced stage with poor outcome because of rarity and lack of specific criteria for early detection. Aims and objectives: The main aim was to evaluate the impact of age, gender andstone characteristics on risk of developing UUTC in patients with chronic nephrolithiasis. We also discuss the role of aberrant angiogenesis (AA) and immunohistochemical expression of p53, p16INK4a, CK20 and Ki-67 in diagnosis of pelvicalyceal neoplastic (NL) and pre-neoplastic lesions (PNL) in these patients. Materials and Methods: Retrospective analysis of pelvicalyceal urothelial lesions from 88 nephrectomy specimens were carried out in a tertiary care centre from June 2012 to December 2014. Immunohistochemistry (IHC) was performed on 37 selected cases. Computed image analysis was performed to analyse aberrant angiogenesis. Results: All UUTC (5.7%) and metaplastic lesions were found to be associated with stones. Some 60% were pure squamous cell carcinoma and 40% were transitional cell carcinoma. Odd ratios for developing NL and PNL lesions in presence of renal stone, impacted stones, multiple and large stag horn stones were 9.39 (95% CI 1.15-76.39, p value 0.05), 6.28 (95% CI 1.59-24.85, p value 0.000) and 7.4 (95% CI, 2.29-23.94, p value 0.001) respectively. When patient age was ${\geq}55$, the odds ratio for developing NL was 3.43 (95% CI 1.19-9.88, p value 0.019). IHC analysis showed that mean Ki-67 indices were $3.15{\pm}3.63%$ for non-neoplastic lesions, $10.0{\pm}9.45%$ for PNL and $28.0{\pm}18.4%$ for NL. Sensitivity and specificity of CK20, p53, p16INK4a, AA were 76% and 95.9%; 100% and 27.5%; 100% and 26.5%; 92.3 % and 78.8% respectively. Conclusions: Age ${\geq}55years$, large stag horn stones, multiple stones and impacted stones are found to be associated with increased risk of NL and PNL in UUT. For flat lesions, a panel of markers, Ki 67 index >10 and presence of aberrant angiogenesis were more useful than individual markers.

• Journal of the Korean Geotechnical Society
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• v.19 no.1
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• pp.93-102
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• 2003

Unconfined compression test (UC) has been widely used to determine the undrained shear strength ($c_u$) of clay, because it is convenient and economical. However, UC can not represent the behaviour of in-situ stress condition and the strength obtained by the test is generally underestimated compared to that of triaxial compression, due to no confining pressure. Therefore, a simple and practical method to correct the ($c_u$) for sample disturbance and to be used in geotechnical practice is needed. This study is aimed at proposing the method to estimate in-situ undrained shear strength from UC with suction measurement. The proposed method is based on theoretical shear strength equation of perfect sample (Noorany & Seed, 1965), and effective overburden stress and analysis results ($A_f,\phi'$) of effective stress behaviour by UC are needed for the equation. The shear resistance angle ($\phi'$) can be simply estimated through the result that $K_f$-line slope of the UC is 1.6 times higher than that of triaxial compression test. The result of this study shows that the measured strength by this method is very similar to that of the undrained shear strength by triaxial compression test (CK$_0$UC).

• Journal of the Korean Geotechnical Society
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• v.19 no.6
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• pp.15-22
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• 2003

In the conventional load transfer analysis for a steel pipe drilled shaft, it was assumed that the concrete's strain is the same as the measured steel's strain and the elastic modulus of the steel and the concrete calculated by the formular as prescribed by specification is used in the calculation of pile axial load. But, the pile axial load calculation by conventional method differed to some extent from the actual pile load. So, the behavior of a steel pipe drilled shaft could not be analyzed exactly. Thus, the necessity to measure the strain for each pile component was proposed. In this study, a new approach for load transfer measurement of large diameter drilled shafts was suggested ; the strain of each pile component(i. e., steel and concrete) was measured by DRS(Deformable Rod Sensor), the elastic modulus was determined by the uniaxial compression test for concrete specimens made at test site and a value of elastic modulus was evaluated as average tangential modulus corresponding to the stress level of the (0.2-0.6)$f_{ck}$. Field application was confirmed by the results of load transfer measurement tests for 3 drilled shafts. The errors for calculated pile head load were -11 ∼16% and 3.4% separately.

• Journal of Educational Research in Mathematics
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• v.19 no.4
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• pp.545-564
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• 2009

TPACK (Technological Pedagogical Content Knowledge) adds the technological knowledge to PCK (Shulman 1986), completing the combination of three kinds of knowledge, i.e. teacher's content knowledge (CK), pedagogical knowledge (PK), and technological knowledge (TK). In this study, I seek to design methodological ways to improve TPACK for preservice mathematics teachers by developing and analyzing team project-based classes with technology in a class of the first semester 2009 in a teacher's college in Seoul, South Korea. The goal of the team project is to design classes to teach mathematics with technology by selecting technology tools suitable for specific mathematical concepts or mathematics sections. In the early stage of the class in the college, the confidence levels among the preservice mathematics teachers were relatively low but increased in the final stage their mathematics teaching efficacy up to from 3.88 to 4.50. Also, the pre service mathematics teachers answered the team project was helpful or very helpful in developing TPACK; this result proves that lectures with technology which based on team project are excellent tools for the teacher to design classes with technology confidently. Considering the teacher's TPACK is one of the abilities to achieve the goals required in the information technology era, the preservice mathematics teachers are asked to plan and develop the lectures with technology, rather than just taught to know how to use technology tools or adapt to specific cases. Finally, we see that national-wide discussion and research are necessary to prepare customized standards and implementable plans for TPACK in South Korea.

• The Journal of Korean Physical Therapy
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• v.15 no.2
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• pp.19-51
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• 2003

To demonstrate the effect of massages on the skeletal muscles of immobilization ddY mice models induced by right side sciatic nerve neurectomy, the cross sectional histological profiles of the muscularis (M) gastrocnemius, M. tibialis cranialis and M. tibialis caudalis were observed after 28 days of treatment of massages with the changes of body weight, thickness of hind limb and individual muscle weights. In addition, changes of serum aspartate amino- transferase (AST) and creatine phosphokinase (CK) levels were also demonstrated with diameter of individual muscle fiber and muscle fasciculata, and number of muscle fiber in each of three types of muscles located in the calf. The experimental groups were divided into five groups, 1) Sham-operated group (Sham), 2) Neurectomized but not massage control group (Control), 3) Neurectomized and massage at knee joint regions (T1), 4) Neurectomized and massage at calf regions (T2), and 5) Neurectomized and massages at achilles tendon regions (T3). The experimental animals were used 5 per groups. The results are as follow: 1. No significant changes of body weight were demonstrated in this groups during whole experimental periods compared to that of Sham group. In addition, no significant changes of body weight gains during experimental periods (Day 0 - Day 27: 28 days of treatment) were also observed. 2. The thickness of intact left side hind limb was not changes in all tested groups compared to that of Sham group. However, the thickness of right side hind limb were remarkedly decreased in Control, T1, T2 and T3 groups compared to that of Sham group. In addition, the differences of thickness of hind limb between right and left sides were also significantly increased in Control and massage groups (T1, T2 and T3) compared to that of Sham group. However, the thickness of right side of hind limb were significantly increased and the differences of thickness between both sides of hind limb were dramatically decreased in massage groups compared to that of Control group in followed order: T1 > T3 > T2. 3. Absolute and relative weight of M. gastrocnemius in the intact left side of hind limb was not changes in all tested groups compared to that of Sham group. However, the weight of right side M. gastrocnemius were remarkedly decreased in Control, T1, T2 and T3 groups compared to that of Sham group. In addition, the differences of weight of M. gastrocnemius between right and left sides were also significantly increased in Control and massage groups compared to that of Sham group. However, the weight of right side M. gastrocnemius were significantly increased and the differences of weight between both sides of M. gastrocnemius were dramatically decreased in massage groups compared to that of Control group in followed order: T3 > T1 >. 4. Absolute and relative weight of M. tibialis cranialis in the intact left side was not changes in all tested groups compared to that of Sham group. However, the weight of right side M. tibialis cranialis were remarkedly decreased in Control, T1, T2 and T3 groups compared to that of Sham group. In addition, the differences of weight of M. tibialis cranialis between right and left sides were also significantly increased in Control and massage groups compared to that of Sham group. However, the weight of right side M. tibialis cranialis were significantly increased and . the differences of weight between both sides of M. tibialis cranialis were dramatically decreased in massage groups compared to that of Control group in followed order: T3 > T1 > T2. 5. Absolute and relative weight of M. tibialis caudalis in the intact left side was not changes in all tested groups compared to that of Sham group. However, the weight of right side M. tibialis caudalis were remarkedly decreased in Control, T1, T2 and T3 groups compared to that of Sham group. In addition, the differences of weight of M. tibialis caudalis between right and left sides were also significantly increased in Control and massage groups compared to that of Sham group. However, the weight of right side M. tibialis caudalis were significantly increased and the differences of weight between both sides of M. tibialis caudalis were dramatically decreased in massage groups compared to that of Control group in followed order: T3 > T1 > T2. 6. A significant increase of serum AST levels were demonstrated in Control group. However, serum AST levels of massage groups were significantly decreased compared to that of Control group in followed order: T3 > T1 > T2. In case of 73 group, the values decreased into similar levels compared to that of Sham group. 7. A significant increase of serum CK levels were demonstrated in Control group. However, serum CK levels of massage groups were significantly decreased compared to that of Control group in followed order: T3 > T1 > T2.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.9
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• pp.1298-1304
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• 2006

The aim of this study was to provide basic haematological information to allow improved nutritional management for velvet production in spotted deer (Cervus nippon) by investigating biochemical changes in blood values during the antler growth period. Blood samples, obtained from the jugular vein of twenty-five deer, were taken every 10 days from casting (day 0) to harvesting (day 50) of velvet antler. Negligible changes were found in the concentrations of total protein, albumin, and creatinine during the antler growth period, but there were significant changes in the concentrations of urea (p<0.05) and uric acid (p<0.01). The concentration of triglyceride was significantly higher (p<0.05) during the antler growth period compared to casting time, while serum high-density lipoprotein concentrations were low and remained unchanged during the antler growth period. Serum glucose concentration increased (p<0.05) significantly and was slightly changeable during antler growth. The serum concentrations of Ca and P did not fluctuate during antler growth, while those of Na, K and Cl showed slight differences between the time of casting and the rest of the antler growth period. No significant changes in concentrations of AST, ALT, amylase, CK, GGT and LDH were detected during the antler growth period. However, the concentration of ALK-P increased during antler growth reaching its peak on day 50 after casting. We found a significant difference in the concentration of ALK-P between the time of casting and the rest of the antler growth period (p<0.01). Consequently, antler growth was associated with mild changes in measured serum biochemical values with the exception of ALK-P activity in spotted deer.

• Journal of The Korean Society of Clinical Toxicology
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• v.3 no.1
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• pp.27-32
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• 2005

Purpose: The frequency of carbon monoxide poisoning has been decreased in the interior of the Korea. But occasionally it is occurred and the risk of exposure is high in working place so far. Because of the characteristics of gas, the detection of exposure and poisoning could be delayed and fatality is high. We should apprehend of carbon monoxide poisoning. So we would report analysis of patients with carbon monoxide poisoning. Methods: A retrospective review of CO poisoned patients visited emergency department from January 2000 to December 2004 was conducted. Results: 24 patients were enrolled. Their average of age was $37.6\pm20.9$ years old and COHb was $19.4\pm13.32\%$. The blood level of initial COHb and mental status on arrival were not correlated each other. The blood level of initial COHb and loss of consciousness were not correlated, too. Initial electrocardiography (EKG) was not correlated with cardiac enzymes such as CK-MB and troponin I. But base excess was correlated with mental status on arrival and complication such as rhabdomyolysis. Hyperbaric oxygen therapy was correlated with base excess and mental status on arrival. Conclusion: The clinical features of carbon monoxide poisoning are nonspecific. For proper diagnosis, it is important that we should consider patient's environment and take patient's history carefully. The blood level of initial COHb does not reflect severity of poisoning accurately. So We should determine the treatment of choice depending on patient's status.