• Journal of Physiology & Pathology in Korean Medicine
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• v.33 no.1
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• pp.10-16
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• 2019

In order to investigate the effects of Eucomiae Cortex extracts on the depression caused by aging, histochemistry and immunohistochemistry were performed on the hippocampus of aged rats and the following results were obtained. Experimental animals were divided into three groups as follows: 8 week old ICR male mice, Aging-elicited group (AE group) and Eucomiae Cortex treatment group (EC group) 50 week old male ICR mice were used. The control group and AE group did not take any treatment and did not restrict diets and negatives. In the EC group, 0.51g/kg of Eucomiae Cortex extract was dissolved in distilled water once a day for 6 months. The Eucomiae Cortex extract reduced pyramidal neuronal damage in C3 hippocampus and dentate gyrus, increased DJ-1, SHH positive responses in aged mouse hippocampus, and 8-OHdG positivity was reduced, ${\beta}$-endorphin positivity was reduced in aged mouse substantia nigra. Therefore, based on the above results, Eucomiae Cortex extract reduces damage of pyramidal neurons in the hippocampus caused by aging, inhibits neuronal cell death, induces proliferation and differentiation of stem cells in the hippocampus, reduces DNA damage-induced oxidative stress, so improves the reduction of hippocampus volume. It is also thought to improves depression due to aging through ${\beta}$-endorphin which enhances mood through the inhibition of pain.

• Korean Journal of Poultry Science
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• v.46 no.1
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• pp.1-10
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• 2019

The most important times during the development of young chicks are the days immediately prior to hatching and the days immediately after hatching, known as the perinatal period. A sufficient supply of nutrients during the perinatal period is a crucial during the late stage of embryonic development and the starvation period of the young chicks. The delayed post-hatch holding time can restrict the development of the gastrointestinal tract, reduce final body weight, impair muscle development, and change immunological capacities. These symptoms are deleterious to the development of young chicks. Therefore, the post-hatch holding time and its influence on the fitness of young chicks are major concerns to the poultry industry. The in ovo feeding is a practical technology for perinatal nutrition to optimize poultry production and for attenuating the stress experienced by fasting young chicks. This study will discuss in ovo feeding and its effect on the development of the chick embryo, the establishment of a healthy microbiota, and the improving immune response.

• Journal of the Korean Geotechnical Society
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• v.26 no.7
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• pp.117-133
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• 2010

A hybrid system of soil-nailing and compression anchor is proposed in this paper; the system is composed of an anchor bar (installed at the tip) with two PC strands and a steel bar. After drilling a hole, installing proposed hybrid systems, and filling the hole with grouting material, prestress is applied to the anchor bar to restrict the deformation at the head and/or to prevent shallow slope failures. However, since the elongation rate of PC strand is much larger than that of steel bar, yield at the steel bar will occur much earlier than at the PC strand. It means that the yield load of the hybrid system will be overestimated if we simply add yield loads of the two - anchor bar and PC strands. It might be needed to try to match the yielding time of the two materials by applying the prestress to the anchor bar. It means that the main purpose of applying prestress to the anchor bar should be two-fold: to restrict the deformation at the nail head; and more importantly, to maximize the design load of the hybrid system by utilizing load transfer mechanism that transfers the prestress applied at the tip to the head through anchor bar. In order to study the load transfer mechanism in a systematic way, in-situ pullout tests were performed with the following conditions: soil-nailing only; hybrid system with the variation of prestress stresses from 0 kN to 196 kN. It was found that the prestress applied to the anchor system will induce the compressive stress to the steel bar; it will result in decrease in the slope of load-displacement curve of the steel bar. Then, the elongation at which the steel bar will reach yield stress might become similar to that of PC strands. By taking advantage of prestress to match elongations at yield, the pullout design load of the hybrid system can be increased up to twice that of the soil-nailing system.

• Journal of the Korea Concrete Institute
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• v.16 no.4 s.82
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• pp.521-528
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• 2004

In general, polymer concrete has more excellent mechanical properties and durability than Portland cement concrete, but very sensitive to heat and has large deformations. In this study, the long-term creep behaviors was predicted by the short-term creep test, and then the characteristic of creep of recycled-PET polymer concrete was defined by material and experimental variables. The error in the predicted long-term creep values is less than 5 percent for all polymer concrete systems. The filler carry out an important role to restrict the creep strains of recycled PET Polymer concrete. The creep strain and specific on using the $CaCO_3$ were less than using fly-ash. The creep increases with an increase in the applied stress, but not proportional the rate of stress increase ratio. The creep behavior of polymer concrete using recycled polyester resin is not a linear viscoelastic behavior.

• Applied Biological Chemistry
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• v.40 no.3
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• pp.232-237
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• 1997

Soybean plants inoculated Bradrhizobium japonicum MN 110 were grown in outdoor perlite pots with nitrogen free nutrient solution containing 1.0 mM-P(control) and 0.05 mM-P(stress) and harvested at 28, 35, 42 and 49 days after transplanting (DAT) to examine the effect of phosphorus deficiency on ureide concentration of and distribution to diffrent plant organ in nitrogen fixing soybean plant during the vegetative growth. Total dry mass of control plants increased 8.9 fold and that of phosphorus deficient plant increased 2.7 fold during the experimental period. Phosphorus deficiency reduced total phosphorus and nitrogen accumulation by 80%,40% respectively, at 28 DAT and 93%, 84%, respectively, at 49 DAT. Nitrogen concentration was reduced by phosphorus deficiency in all tissues with leaf and stem tissues affected to a greater degree than nodule and root tissues at every sampling date. Phosphorus deficiency significantly reduced soluble reduced-N and ureide-N concentration in leaf and stem but did not affect those in root. The proportion of soluble reduced-N in leaf was reduced from 60% to 50% but increased from 10% to 20% in the roots. The proportion of ureide-N in leaf of control plants was higher than that in phosphorus deficient plants, whereas, roots of phosphorus deficient plants contained a higher propotion of ureide-N than those of control plants. These indicated that phosphorus deficiency not only inhibit nitrogen fixation of nodules but also restrict the translocation of fixed nitrogen out of the root system into the xylem.(Received April 4, 1997; accepted May 2, 1997)

• Journal of radiological science and technology
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• v.38 no.3
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• pp.287-294
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• 2015

As employment changes quickly in structure, enterprises put more and more stress on basic vocational competency skills. This study aimed to grasp the basic vocational competency skills of S College Department of Radiological Technology students and present the basic data. The gathered data was analyzed using T-Test and Oneway ANOVA. The analysis showed that the students mostly had average or higher levels in the seven areas of basic vocational competency skills. Reading and writing skills among communication skills were the lowest, followed by the skills of understanding global culture and using foreign languages among organization understanding skills, and then by numeracy skills. On the contrary, interpersonal relationship skills were the highest in level. This indicates that the students will establish good interpersonal relationships with hospital patients and members. There were also statistically significant differences in reading and writing skills among communication skills, numeracy skills, and the skills of understanding global culture and using foreign languages among organization understanding skills. This study measured the basic vocational competency skills of S College Department of Radiological Technology students, which might somewhat restrict the application of its results to the students of all universities. The results show that students should be instructed to improve the skills of communication, numeracy, organization understanding, self-management skills, etc. Therefore, it seems necessary using various programs customized to school years and student levels and performing education properly connected to industrial establishments to foster the workforce with excellent basic vocational competency skills.

• Journal of Korean Tunnelling and Underground Space Association
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• v.4 no.4
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• pp.277-286
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• 2002

Most of the problems in dealing with the tunnel construction are the uncertainties and complexities of the stress conditions and rock strengths in ahead of the tunnel excavation. The limitations on the investigation technology, inaccessibility of borehole test in mountain area and public hatred also restrict our knowledge on the geologic conditions on the mountainous tunneling area. Nevertheless an extensive and superior geophysical exploration data is possibly acquired deep within the mountain area, with up to the tunnel locations in the case of alternative design or turn-key base projects. An appealing claim in the use of artificial neural networks (ANN) is that they give a more trustworthy results on our data based on identifying relevant input variables such as a little geotechnical information and biological learning principles. In this study, error back-propagation algorithm that is one of the teaching techniques of ANN is applied to presupposition on Rock Mass Ratings (RMR) for unknown tunnel area. In order to verify the applicability of this model, a 4km railway tunnel's field data are verified and used as input parameters for the prediction of RMR, with the learned pattern by error back propagation logics. ANN is one of basic methods in solving the geotechnical uncertainties and helpful in solving the problems with data consistency, but needs some modification on the technical problems and we hope our study to be developed in the future design work.

• Journal of the Microelectronics and Packaging Society
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• v.20 no.3
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• pp.31-35
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• 2013

TSOP(Thin Small Outline Package) is the IC package using lead frame, which is the type of low cost package for white electronics, auto mobile, desktop PC, and so on. Its performance is not excellent compared to BGA or flip-chip CSP, but it has been used mostly because of low price of TSOP package. However, it has been issued in TSOP package that thermal deflection of lead frame occurs frequently during molding process and Au wire between semiconductor die and pad is debonded. It has been required to solve this problem through substituting materials with low CTE and improving structure of lead frame. We focused on developing the lead frame structure having thermal stability, which was carried out by numerical analysis in this study. Thermal deflection of lead frame in TSOP package was simulated with positions of anti-deflection adhesives, which was ranging 198 um~366 um from semiconductor die. It was definitely understood that thermal deflection of TSOP package with anti-deflection adhesives was improved as 30.738 um in the case of inside(198 um), which was compared to that of the conventional TSOP package. This result is caused by that the anti-deflection adhesives is contributed to restrict thermal expansion of lead frame. Therefore, it is expected that the anti-deflection adhesives can be applied to lead frame packages and enhance their thermal deflection without any change of substitutive materials with low CTE.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.1
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• pp.45-52
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• 1985

Phytotron and field experiments were conducted to determine the influence of morphological development and environmental temperature on synthesis, translocation and accumulation behaviour of Fructosan, Monoand Disaccharose in corn cv. Blizzard and fodder sorghum cv. Sioux and Pioneer 931 at Munich technical university. Sorghum and maize plants were grown for 42 days at 4 temperature regimes (30/25, 25/20, 28/18 and 28/8 dog C) and mid-summer sunlight over 13-h days. The obtained results are summarized as follows: 1 Non-structural carbohydrates in maize and sorghum were accumulated mainly as Mono- and Disaccharose. The concentrations of Mono- and Disaccharose were increased markedly after differentiation of growing points and shown at early milk stage the highest contents with 27.8-29.1% and 16.8-20.4% for maizeand sorghums respectively. 2. Non-structural carbohydrates were accumulated mainly in stalk. However, during the late maturity the most of Mono- and Disaccharose were translocated into grain and reserved as starch. The increase of starch was associated with decrease of total non-structural carbohydrates. 3. Fructosan synthesis was not affected by morphological changes and environmental factors, which shows a value of 1.5-2.5% in whole stage of maize and sorghum. 4. Sorghum and maize plants were shown to have a great photosynthetic rates to high temperature. Reserved Mono- and Diaaccharose were, however, declined when temperature exceeded 30 dog C. Under cold stress at l8/8 deg C non-structural carbohydrates were not translocated and also were accumulated in leaves too much that cause to restrict of photosynthesis. 5. Net Energy Lactation (NEL) of sorghum and maize were directly associated with synthetic rates of non-structural carbohydrates, especially Mono- and Disaccharose. The highest values of NEL were found at physiological maturity stage with 6.6- 6.9 MJ and 5.7-6.0 MJ-NEL/kg for maize and sorghum respectively.