• Explosives and Blasting
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• v.25 no.2
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• pp.47-60
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• 2007

The blast demolition technology has been used to demolish various industrial facilities and tall buildings since 1950s in the advanced countries such as USA and U.K. It is now considered as one of safe demolition methods in the above countries. In Korea, several companies have tried to introduce blast demolition technology in the early days of the 1990s. However, this technology is still at the beginning stage and not fully adopted due to situation of avoiding technology transfer by overseas technical tie-up companies, lack of objects to be demolished and low level recognition on blast demolition. This technology shall be considered as a cutting edge technology to be applicable to demolition of skyscrapers, various industrial structures and factory buildings in the near future. Blast demolition of a pier structure was carried out under the site condition where there were already the constructed 2 pier structures of up and down line which had safety problems in an expressway construction project. The pier structures need to be demolished and reconstructed for a short period of time in consideration of the construction work process to be followed.

• Biomolecules & Therapeutics
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• v.21 no.1
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• pp.42-48
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• 2013

Nystatin, a polyene antifungal antibiotic, is a cholesterol sequestering agent. The antifungal agent alters composition of the plasma membrane of eukaryotic cells, whereas its effects on cells are poorly investigated. In the current study, we investigated the question of whether nystatin was able to induce expression of macrophage inflammatory protein-1 (MIP-1). THP-1 cells rarely express MIP-$1{\alpha}$ and MIP-$1{\beta}$, however, upon exposure to nystatin, significantly elevated expression of MIP-$1{\alpha}$ and MIP-$1{\beta}$ was observed in a dose-dependent fashion at the messenger and protein levels. Cellular factors activated by nystatin as well as involved in nystatin-induced expression of MIP-1 proteins were identified in order to understand the molecular mechanisms of action of the anti-fungal agent. Treatment with nystatin resulted in enhanced phosphorylation of Akt, ERK, p38 MAPK, and JNK. Abrogation or significant attenuation of nystatin-induced expression of MIP-$1{\alpha}$ and MIP-$1{\beta}$ was observed by treatment with Akt inhibitor IV, LY294002, and SP6001250. Inhibition of ERK or p38MAPK using U0126 and SB202190 did not lead to attenuation of MIP-1 expression. In addition, inhibitors of protein kinase C, such as GF109203X and Ro-318220, also attenuated expression of MIP-1. These results indicate that nystatin is able to activate multiple cellular kinases and, among them, Akt and JNK play primary roles in nystatin-induced expression of MIP-1 proteins.

• Journal of the Society of Naval Architects of Korea
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• v.34 no.4
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• pp.1-11
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• 1997

When a barge is towed by a tug boat using a tow line, the barge is frequently subject to a large sway motion induced from its inherent yaw motions. This large sway motion combined with external forces due to winds and waves may makes the towing to be difficult or even dangerous. It has been reported that in worse situations, barges or tugs are capsized. In addition, the large sway motion of the towed barge gives a menace to the safety of ships navigating nearby. This paper is the results of the experimental investigation into the course stability of an 8,000 DWT barge using a Towing Tank and a Circulating Water Channel. Various skegs are designed and course stability tests for the barge with skegs are conducted in calm water and in irregular waves. It is observed that an effective skeg attached to the barge enables the sway motion to be zero while the sway amplitude of the bare hull is around 10 times its breadth.

• International Journal of Highway Engineering
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• v.5 no.1 s.15
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• pp.1-10
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• 2003

The objective of pavement design, just as with the design of other structures, is to obtain the most economical designs at specified levels of reliability. Methods that yield designs with different levels of reliability are undesirable, and over the course of time design approaches in the U.S. and Europe have converged toward the Load and Resistance Factor Design (LRFD) format in order to assure uniform reliability. At present the LRFD format has been implemented in concrete, steel, wood and bridge design specifications. In this paper, reliability theories are used to illustrate the development of an LRFD format for Mechanistic-Empirical (M-E) design of flexible pavements as an alternative of its reliability module. It is shown in this paper that ten candidate pavement sections designed with a reliability level using the AASHTO design guide (1986) do not have uniform structural reliability in terms of pavement mechanistic distress such as fatigue cracking and the uniform reliability can be achieved by using the LRFD format.

• Journal of Biosystems Engineering
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• v.38 no.3
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• pp.185-191
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• 2013

Purpose: The present study focused on the estimation of soluble solids content (SSC) of chestnut using reflectance and transmittance spectra in range of VIS/NIR. Methods: Four species intact/peeled chestnuts were used for acquisition of spectral data. Transmittance and reflectance spectra were used to develop the best PLS model to estimate SSC of chestnut. Results: The model developed with the transmitted energy spectra of peeled chestnuts rather than intact chestnuts and with range of NIR rather than VIS performed better. The best $R^2$ and RMSEP of cross validation were represented as 0.54 and $1.85^{\circ}Brix$. The results presented that the reflectance spectra of peeled chestnuts by species showed the best performance to predict SSC of chestnut. $R^2$ and RMSEP were 0.55 and $1.67^{\circ}Brix$. Conclusions: All developed models showed RMSEP around $1.44{\sim}2.54^{\circ}Brix$, which is considered not enough to estimate SSC accurately. It was noted that $R^2$ of cross validation that we found were not high. For all that, grading of the fruits in two or three classes of SSC during postharvest handling seems possible with an inexpensive spectrophotometer. Furthermore, the development of estimation of SSC by each chestnut species could be considered in that SSC distribution is clustering in different range by species.

• Nuclear Engineering and Technology
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• v.47 no.3
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• pp.380-387
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• 2015

A lead slowing-down spectrometer (LSDS) system is a promising nondestructive assay technique that enables a quantitative measurement of the isotopic contents of major fissile isotopes in spent nuclear fuel and its pyroprocessing counterparts, such as $^{235}U$, $^{239}Pu$, $^{241}Pu$, and, potentially, minor actinides. The LSDS system currently under development at the Korea Atomic Energy Research Institute (Daejeon, Korea) is planned to utilize a high-flux ($>10^{12}n/cm^2{\cdot}s$) neutron source comprised of a high-energy (30 MeV)/high-current (~2 A) electron beam and a heavy metal target, which results in a very intense and complex radiation field for the facility, thus demanding structural shielding to guarantee the safety. Optimization of the structural shielding design was conducted using MCNPX for neutron dose rate evaluation of several representative hypothetical designs. In order to satisfy the construction cost and neutron attenuation capability of the facility, while simultaneously achieving the aimed dose rate limit (< $0.06{\mu}Sv/h$), a few shielding materials [high-density polyethylene (HDPE)eBorax, $B_4C$, and $Li_2CO_3$] were considered for the main neutron absorber layer, which is encapsulated within the double-sided concrete wall. The MCNP simulation indicated that HDPE-Borax is the most efficient among the aforementioned candidate materials, and the combined thickness of the shielding layers should exceed 100 cm to satisfy the dose limit on the outside surface of the shielding wall of the facility when limiting the thickness of the HDPE-Borax intermediate layer to below 5 cm. However, the shielding wall must include the instrumentation and installation holes for the LSDS system. The radiation leakage through the holes was substantially mitigated by adopting a zigzag-shape with concrete covers on both sides. The suggested optimized design of the shielding structure satisfies the dose rate limit and can be used for the construction of a facility in the near future.

• Journal of Korea Ship Safrty Technology Authority
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• no.7 s.25
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• pp.47-63
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• 2008

저항성능 측면에서 한국 어선선형의 특성을 파악하기 위하여, 본 연구에서는 한국과 일본에서 건조되어진 대표적인 어선을 한 척씩 선정하여 두 어선의 선형적 특성을 비교하였다. 또한 한국 어선의 선형적 특성들, 즉 일부 대표적인 선형요소들과 이를 제외한 기타의 국부적 선형특성들을 일본어선의 선형을 참고로 보정함으로써 우리나라 어선들의 저항성능을 향상시킬 수 있는 방안에 대하여 연구하였다. 한국어선과 일본어선은 해양환경과 어업의 종류가 다를 뿐만 아니라 관습적인 이유 등으로 선형의 차이가 있게 되며, 이것은 한국 어선이 일본 어선에 비하여 같은 배수량을 가지더라도 배 길이가 짧은 반면 폭이 넓으며 흘수가 얕은 대표적인 선형요소들의 차이로 확인할 수 있다. 이러한 차이를 고려하여, 일본어선들에 대한 유효마력 추정프로그램을 한국어선들에 맞게 보정.개발하는 과정을 통하여 양국 어선의 저항성능 차이를 확인할 수 있었으며, 보정된 프로그램을 이용하여 연구대상의 한국어선에 대한 저항저감효과를 줄 수 있는 선형요소들을 도출함으로써 선형요소들의 변화에 따른 저항성능 효과를 확인할 수 있었다. 그러나 선형요소들의 보정에도 불구하고 한국어선의 저항성능은 여전히 일본어선의 그것보다 떨어짐을 확인하여, 본 연구에서는 대표적인 선형요소들뿐만 아니라 국부적 선형특성 즉, 선수부에서 차인선(chine line) 경사도, 용골의 형상, 선미길이(용골 끝에서 선미단까지의 거리)를 각각 보정해 봄으로써 보다 더 큰 저항성능의 개선효과를 확인하였다. 본 연구결과는 앞으로 저항성능이 우수하면서도 실용 가능한 개량된 한국 어선선형의 개발에 기초적인 자료로서 활용이 가능할 것으로 사료된다.

• The Journal of Korean Medicine
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• v.38 no.3
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• pp.86-95
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• 2017

Objectives: The purpose of this clinical research was to investigate the effects of herbal cosmetics containing Caffeic acid phenethyl ester (CAPE), an ingredient compound of various herbs including Vespae Nidus, on the Whitening Effects. Methods: A total of 20 subjects who visited Pusan National University Hospital from March 2nd, 2017 to April 11th, 2017 were included. In this study, we evaluated the visual evaluation, the melanin index (M) and erythema index (E) through skin analysis equipment, the subjective whitening improvement analysis, and the adverse reaction according to product use. Statistical analysis was performed with independent t-test and Mann-Whitney's U test. Statistical significance was achieved if the probability was less than 5% (p<0.05) Results: As a result of the visual evaluation, it was effective in improving skin whitening. The subjective whitening improvement analysis also showed positive results. However, no statistically significant differences were found between the test and control cosmetics in the melanin index (M) and erythema index (E) through skin analysis equipment. In the safety evaluation, some adverse reactions were reported, but no significant were observed directly from cosmetics. Conclusions: Considering the above results, we have confirmed the possibility of herbal cosmetics containing containing CAPE of Vespae Nidus Extracts.

• Journal of Community Nutrition
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• v.1 no.2
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• pp.75-80
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• 1999

Special nutritional foods are one category of processed foods. In this category, 5 different food standards are defined in the current rule of the Korean Food Code ; that is, infant formulae, complementary foods for infants and young children, foods nutrient supplementation, processed dietary fiber-based foods, and foods for special dietary uses. The major differences between the special dietary uses. The major difference between the special nutritional foods and the other processed foods is that the special nutritional foods are characterized by their dietary uses for specific population groups rather than food ingredients or manufacturing and processing techniques which characterize and distinguish most of other processed foods. Although several countries establish similar standards for this type of foods, they use different legal names such as foods for special dietary uses(U.S.A., CODEX, Japan), foodstuffs intended for particular nutritional uses(EC), or special purpose foods(Australia). In addition, there are some other differences in the definitions for these food types and categorization of food types among countries. The major difference in the definitions is the description of 'special dietary uses' by specifying certain population groups whose nutrient requirements are different from those of ordinary men due to physiological or physical conditions and therefore may not be sufficiently met by consuming ordinary foods. The categorization of this type of foods is based on the type of dietary uses in the other countries, whereas we include foods simply supplemented with nutrients or foods having certain components such as dietary fibers even if these foods types do not have special dietary sues. Recently, a revision of standards for special nutritional food has been proposed. However, the description of 'special dietary uses' is not clearly indicated in the definition, and some food types which should not be categorized into the special nutritional foods still remain in this category. In order to correct these problems, the standard of food labeling in the Food Safety Law needs to be revised along with revision of food standards in the Food Code.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.985-988
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• 2008

Maglev is a system that a train runs levitated above a rail. Therefore it is very important to maintain a constant levitation gap for achieving serviceability and ride comfort. This study is a cooperation research subject of the 3-1 subject, performance improvement of maglev track structures, of the Center for Urban Maglev Program in Korea, started in 2006. The aim of this study is development of rapid constructions of bridge superstructure for maglev. At present, precast deck is widely used because of its superiority to cast-in-place concrete on quality and the term of works. The research group suggested basic systems of maglev guideway with PSC-U type and trapezoidal open steel box type girder, and precast deck, cooperating with Korea Railroad Research Institute, the managing institute of the 3-1 subject. In this study, full-scale structure was fabricated for structural safety evaluation of precast decks and rail, and a static performance test of those structures was performed.