• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.561-574
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• 2018

In this study, regional variations and factors associated with prevalence of metabolic syndrome were grasped using GWR (geographically weighted regression) and methodologies for the efficient management of metabolic syndrome were then set up to resolve health inequalities. Based on the National Health Screening Statistical Yearbook published by the National Health Insurance Service (NHIS), community health survey (KCDC) and other governmental institutions, indicators of social structural and mediation factors related to the regional prevalence of metabolic syndrome were collected. First, the existence of indicators to measure variations in metabolic syndrome were confirmed with the collected data by calculating the EQ (extremal quotient) and CV (coefficient of variations). The GWR, which is able to take spatial variations into consideration, was then adopted to analyze the factors of regional variations in metabolic syndrome. The GWR analysis revealed that severity and management of the main causes need to be prioritized in accordance with the prevalence of metabolic syndrome. Consequently, the order of priority in management of regional prevalence of metabolic syndrome was established, and plans that can increase the effectiveness of management of metabolic syndrome were confirmed to be feasible.

• Journal of the Korean Society of Hazard Mitigation
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• v.7 no.5
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• pp.129-137
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• 2007

It is very urgent to research the proper recycling method of marine dredged soil as construction material for environmental conservation. Couple of developed countries have been lots of related researches on recycling of marine dredged soil for marine environmental conservation. This is highly imperative in our country. A small-scaled model test for underground pipe has been conducted on the use of controlled low strength materials with marine dredged soil. The flexible pipe, which is called PVC, was used. Four different testing materials, such as natural sand, insitu-soil, sand-CLSM with marine dredged soil and insitu-soil CLSM with marine dredged soil, were used. The vertical and lateral displacement of pipe with CLSM is one tenth of common granular materials. Also, the use of CSLM showed lower lateral and vertical pressure than that of common granular materials. The main reason is the effect of cement hardening of CLSM. This could increase of the stiffness of pipe with backfill materials. In this study, the data presented show that marine dredged soil and in-situ soil can be successfully used in CLSM and reduce the deformation and earth pressure on flexible pipe.

• Journal of the Korean Society for Marine Environment & Energy
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• v.8 no.3
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• pp.111-115
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• 2005

The concentration of atmosphere carbon dioxide ($CO_2$) which is one of the major greenhouse gas, continues to rise by the increase in fossil fuel consumption, forest destruction and decrease of biological diversity, etc. In order to weaken the global warming, a reduction of $CO_2$ discharge to the atmosphere is required. The $CO_2$ ocean sequestration technology utilizes the intrinsic oceanic capacity of $CO_2$ absorption, diluting and/or dispersing the liquefied $CO_2$ in the deep ocean (>2,000 m). This geo-engineering approach is regarded as one of the occasions to mitigate the $CO_2$ concentration in the atmosphere. Some developed centuries such as Japan, USA, Norway, etc. have intensively carried out the projects on the research and development of $CO_2$ ocean sequestration since 1990s. There have been several approaches to develop the relative technological system to mitigate the increasing $CO_2$, however, there was no systematic and practical R&D programme in the $CO_2$ ocean sequestration. This paper has described the state of the art on the three optional methods of $CO_2$ sequestration, and compared with them in the aspect of the applicable possibility.

• Microbiology and Biotechnology Letters
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• v.48 no.3
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• pp.328-336
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• 2020

Parachlorella sp. is an efficient fatty acid producer that can be used in the production of biofuels, feeds, and fertilizers. Microalgae show varying responses to culture conditions, even those within the same species. In this study, growth and fatty acid composition of a newly isolated Parachlorella sp. from the Nakdong river of Korea in different culture media were investigated. The microalga was cultivated in 400 ml bubble column photobioreactors using BG-11, BBM, TAP, and modified TAP (MTAP) media. It was shown that using BBM led to greater fatty acid accumulation (34%), while using TAP medium led to greater biomass productivity (0.34 g/l/day). Composition of the TAP medium was modified to have the N:P ratio of BBM while also varying concentrations of N and P to improve fatty acid productivity. One of the modified TAP media, MTAP-1 (104.8 mgN/l, 135.2 mgP/l, N:P ratio = 0.77), showed the highest fatty acid concentration of 0.69 ± 0.04 g/l, while those from TAP and BBM were 0.48 ± 0.06 g/l and 0.40 ± 0.02 g/l, respectively. The results showed that microalgal fatty acid productivity could be enhanced by changing the N:P ratio and concentrations.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.671-675
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• 2012

This study was conducted to establish the BMPs (Best Management Practices) for preventing pollutant loadings from paddy rice field applied livestock liquid manure from 2008 through 2011. Cultivated paddy rice fields (Gyeonggi province, Korea) were treated with SCB (Slurry composting and bio-filtration process) liquid fertilizer. The BMPs for paddy rice field developed in this study includes: 1) the controlling a drainage water gate in paddy rice field from right after SCB liquid fertilizer application to 3 weeks after rice transplanting; 2) livestock liquid fertilizer application to paddy rice soils in 20 days before rice transplanting to encourage the utilization of liquid fertilizer; 3) preservation of surface water depth to 5 cm in a paddy field right after SCB liquid fertilizer applied to minimize a water pollution and enhance the utilization of liquid fertilizer; and 4) blocking a water gate at least for 2 days to inactivate E. coli survival. The findings of this study will provide useful and practical guideline to applicators of agricultural soil in deciding appropriate handling and time frames for preventing pollution of water quality for sustainable agriculture.

• 한국방재학회:학술대회논문집
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• 2011.02a
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• pp.74-74
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• 2011

본 연구에서는 중앙경간 54m, 교폭 4m의 사장교형식의 보도교로 측경간은 계단으로 이루어진 1경간 케이블교량을 대상으로 보행하중에 의한 수직진동을 제어하기 위해 제진장치(TMD)를 적용하기로 하고 실물 TMD의 설계 및 제작 그리고 설치 및 제어성능실험을 수행하였다. 우선 사장교형식의 교량. 그리고 1경간 교량이라는 점에서 상대적으로 감쇠율이 낮을 것으로 예측되었고 또한 54m의 경간장이 보행자가 가진 주파수에 근접한 고유진동수를 나타낼 것으로 사료되어 Eurocode 2 part 2(EC5-2)의 규준에 따라 1인 및 다수 보행하중에 의한 보도교의 발생가속도를 산출하였다. 이 경우 최대가속도는 다수의 보행자가 연속적으로 진행할 때 발생하였으며, 수직방향의 가속도가 사용성기준을 초과하는 것으로 나타났다. 또한 구조해석프로그램에 의한 고유치 해석결과, 보행하중의 주파수대역내에 진동모드가 존재하는 것으로 나타났다. 따라서 본 교량의 설계단계에 있어서 보행진동을 제어하기 위하여 유지관리가 용이한 수동형의 동조질량감쇠장치(Tuned Mass Damper)를 적용하기로 하였으며 TMD의 설계에서는 TMD의 제어목표를 만족시킬 수 있는 TMD의 가동질량(moving mass)을 우선적으로 결정하였고, 이로부터 Den Hartog의 제안식에 따라 TMD의 고유진동수비, 유효감쇠비를 산정하였다. 산정된 변수들을 이용하여 설계된 TMD는 현장설치 및 튜닝의 편의성을 고려하여 수평 외팔보형식으로 설계, 제작되었으며 제작된 TMD의 경우 회전축에 대해 질량, 스프링, 댐퍼의 중심거리를 조정함으로써 TMD의 진동수, 강성, 감쇠력을 상대적으로 매우 용이하게 조절할 수 있으며, 조정범위 또한 광범위하여 일반 TMD에 비해 현장설치시 대상구조물에 동조시키기가 용이하며, 작동시 마찰감쇠가 거의 없다는 장점이 있다. 현장설치전에 제작된 TMD를 대상으로 자유진동 시험을 통하여 질량의 중심거리, 스프링 크기 그리고 댐퍼의 설치유무를 각각 변화시키며 TMD의 자유진동 데이터를 취득하였다. 각각의 시험에서 얻어진 데이터로부터 스펙트럼해석을 통하여 고유진동수를 구하였고, 자유진동 파형으로 부터 감쇠비를 구하였다. TMD는 일반적으로 제어모드의 변형형상이 가장 큰 곳에 설치되었을 때 최대의 제진효과를 발휘할 수 있다. 그러나 현장여건상 설치가 불가능하거나 미관을 해치는 경우에는 가능한 범위 내에서 TMD 제어효율이 가장 크게 발휘할 수 있는 곳을 선택하여야 한다. 본 보도교의 경우, 중앙경간 중심부에서 가장 큰 모드변형형상을 나타내지만, 보도교의 상판 연결부 등에 따른 TMD 시공문제로 인하여 TMD 설치위치는 교량 중앙에서 양 방향으로 1.25m 떨어진 곳에 대칭으로 총 2기를 설치하기로 하였다. 일반적으로 TMD의 모든 설계변수는 구조물의 설계단계에서 수행된 구조해석결과에 근거하여 설정하므로 완공된 구조물, 즉 실제보도교의 동적특성을 계측하여 정확하게 진동수를 튜닝하여야 한다. 구조해석에 의한 보도교의 수직방향(TMD 작동방향) 고유진동수는 1.5225 Hz이며, 감쇠비는 규준에 의하여 0.6 %로 가정하였다. 그러나 이 값들은 구조해석모델 및 재료적 특성과 시공상의 오차에 의하여 실제와 다를 수 있으므로 현장계측에 의한 확인이 요구된다. 또한 TMD의 제진효율이 설계시의 목표대로 확보되었는지도 확인해야 하므로 현장튜닝 및 성능시험을 실시하였다. 보도교의 가진은 사전에 실시한 상시 미진동계측결과를 토대로 2Hz를 목표로 하여 인력가진실험을 수행하였고, 탁월진동 주파수는 1.9896Hz로 나타나 구조해석결과와 오차가 있음을 알 수 있다. 가진실험결과를 토대로 TMD의 진동수를 최적진동수비로 튜닝하고 인력가진 실험을 다시 실시하여 TMD의 진동제어성능을 검토하였다. TMD 튜닝 전, 후의 보도교 감쇠비를 비교한 결과, TMD를 설치함으로써 약 4.218%의 감쇠비 증가가 있음을 알 수 있다.

• Journal of Acupuncture Research
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• v.25 no.1
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• pp.139-154
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• 2008

목적 : 홍화(紅花)는 활혈거어(活血祛瘀), 해독지통(解毒止痛)의 효능이 있어 관절염, 동맥경화(動脈硬化), 종양(腫瘍), 월경부조(月經不調), 뇌혈전(腦血栓)에 사용되어 왔다. 이에 홍화약침액(紅花藥鍼液)의 분자생물학적 효능 분석을 하고자 Lipopolysaccharide(LPS)로 염증을 유발한 RAW 264.7 cell의 유전자(遺傳子) 발현(發顯)에 미치는 영향을 Microarray를 통하여 관찰하였다. 방법 : RAW cell을 배양하고 홍화약침액(紅花藥鍼液)의 세포 독성을 확인한 후 (1) LPS, (2) 홍화약침액(紅花藥鍼液), (3) 홍화약침액(紅花藥鍼液)과 LPS를 처치했을 때의 유전자 발현양상을 microarray를 이용하여 관찰하였다. 대조군에 비해 2배 이상 발현의 차이가 있는 경우를 유의한 것으로 보았다. 결과 : 8,170개의 유전자 중 (1) LPS를 처치하였을 경우 35개의 유전자에서 발현이 상승되었고, (2) 홍화약침액(紅花藥鍼液)을 처치하였을 경우 11개의 유전자에서 발현이 상승되고 53개의 유전자에서 발현이 억제되었으며, (3) 홍화약침액(紅花藥鍼液)과 LPS를 동시에 처치하였을 경우에는 47개의 유전자에서 발현이 상승되었고 11개의 유전자에서 발현이 억제되었다. LPS 자극으로 발현이 상승되었지만 홍화약침액(紅花藥鍼液)을 처치할 때 발현이 억제되는 유전자는 SUMO1/sentrin specific protease 7(SENP7), Serine(or cysteine) proteinase inhibitor, clade B(ovalbumin), member 7(SERPINB7), M-phase phosphoprotein, mpp8(HSMPP8), Glycogenin 2(GYG2), InaD-like(Drosophila)(INADL), Copine III(CPNE3), Loss of heterozygosity, 11, chromosomal region 2, gene A(LOH11CR2A), Chromosome 9 open reading frame 33(SHC3), NADH dehydrogenase(ubiquinone) 1 beta subcomplex, 2, 8kDa(NDUFB2)로 9개가 있었다. 요약 : 홍화약침액(紅花藥鍼液)이 LPS로 염증을 유발시킨 RAW 264.7 cell의 유전자 발현에 미치는 영향을 Microarray를 통해 분석하였다. 홍화약침액(紅花藥鍼液)이 LPS로 발현을 항진시킨 35개의 유전자 중 9개를 효과적으로 억제하는 것을 확인하여 염증 치료 기전을 시사하는 유용한 자료를 얻을 수 있었으며 홍화약침액(紅花藥鍼液)이 발현을 항진시킨 유전자들을 통해 혈관생성과 종양억제 등 보다 넓은 범위에 대한 연구가 가능할 것으로 사료된다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.3
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• pp.255-263
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• 2017

This paper presents a beam element capable of conducting material and geometric nonlinear analysis for applications requiring the ultimate behavioral analysis of structures with composite cross-sections. The element formulation is based on co-rotational kinematics to simulate geometrically nonlinear behaviors, and it uses the fiber section method to calculate the stiffness and internal forces of the element. The proposed element was implemented using an in-house numerical program in which an arc-length method was adopted to trace severe nonlinear responses(such as snap-through or snapback), as well as ductile behavior after the peak load. To verify the proposed method of element formulation and the accuracy of the program that was used to employ the element, several numerical studies were conducted and the results from these numerical models were compared with those of three-dimensional continuum models and previous studies, to demonstrate the accuracy and computational efficiency of the element. Additionally, by evaluating an example case of a frame structure with a composite member, the effects of differences between composite material properties such as the elastic modulus ratio and strength ratio were analyzed. It was found that increasing the elastic modulus of the external layer of a composite cross-section caused quasi-brittle behavior, while similar responses of the composite structure to those of homogeneous and linear materials were shown to increase the yield strength of the external layer.

• Journal of Life Science
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• v.20 no.2
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• pp.231-236
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• 2010

Antibiotics in veterinary medicine have been used to treat disease, promote growth rate and improve feed efficiency. However, alternative sources are needed because of of bacterial resistance to antibiotics and residues of antibiotics. The present study was carried out to evaluate the effect of CS682, a fermentation product of Korean soil bacteria, on safety, growth rate and feed efficiency, and to evaluate its value as an alternative for antibiotics used as a feed additive. Two dosages of CS682 (0.1% and 1%) were fed to chickens for 28 days. The results showed that, when compared to chickens in the control group, growth and feed efficiency was improved. Also, mortality, hematology, general clinical signs and necropsy were examined. Chickens in the treatment groups showed no adverse effects. A total of 72 weaning pigs were used to confirm the effects of CS682 at one dose level (0.1%) regarding feed efficiency. Supplementation with 0.1% CS682 also resulted in improved weight gain and feed efficiency ratio. Based on these results, CS682 may be effective in improving feed efficiency safely as a feed additive.

• Geotechnical Engineering
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• v.1 no.1
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• pp.59-72
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• 1985

This paper deals with the numerical analysis by the (mite element method introducing Biot's theory of consolidation and the modified Cambridge model proposed by Roscoe school of Cambridge University as constitutive equation and using Christian-Boehner's technique. Especially, time interval and division of elements are investigated in vies of stability and economics. In order to check the validity of author's program, the program was tested with one-dimensional consolidation case followed by Terzaghi's exact solution and with the results of the Magnan's analysis for existing banking carried out for study at Cubzac-les-ports in France. The main conclusions obtained are summarized as follows: 1. In the case of one-dimensional consolidation, the more divided the elements are near the surface of the foundation, the higher the accuracy of the numerical analysis is. 2. For the time interval, it is stable to divide 20 times per 1-lg cycle. 3. At the element which has long drain distance, the Mandel-fryer effect appears due to time lag. 4. Lateral displacement at an initial loading stage predicted by author's program, in which the load was assumed as not concentrative. but rather in grid form, is well consistent with the value of observation. 5. The pore water pressure predicted by author's program has a better accordance with the value of observation compared with Magnan's results. 6. Optimum construction control by Matsuo-Kawamura's method is possible with the predicted lateral displacement and settlement by the program.