• Korean Journal of Heritage: History & Science
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• v.53 no.1
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• pp.106-125
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• 2020

From 1949 to the present day, many Koguryo sites have been excavated, in North Korea. It can also be said that archaeological surveys and studies in North Korea have triggered Koguryo archaeological studies in South Korea. However, since the 1990s, the excavation of Koguryo sites and archaeological research in North Korea has been carried out as an extension of Daedonggang culture. Therefore, these archaeological surveys focused on the Pyongyang and more general northwestern areas of North Korea, and the conclusion was that Koguryo was a powerful nation with a millennium-long history inherited Gojoseon. Beginning in 1945 in North Korea, the archaeological surveys and related systems were organized, and burial mounds, castles, and city remains were excavated under the idea that Koguryo was a millennium-long, strong nation. In addition, archaeological research has been conducted to validate and confirm this belief. On the notion that Koguryo was founded in 277 BCE, it was insisted that the age of the tombs in Pyongyang was increased and Pyongyang took the position as a Vice Capital in the 4^th Century. Recently an excavation of the castle located in Pyongyang supports the idea that Koguryo inherited Gojoseon on a layered basis. However, the archaeological and conceptual grounds for the founding of Koguryo in the 3^rd Century BCE or the succession of Gojoseon and Koguryo were insufficient. As can be seen from the reconstruction of the royal tombs of the Dongmyung and Dangun, the archaeological surveys in North Korea were criticized for their selective discoveries and arbitrary interpretations. This further supports the necessity for joint excavations and academic exchanges between South and North Korea.

• Journal of Marine Bioscience and Biotechnology
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• v.11 no.2
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• pp.52-61
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• 2019

Over the past few decades, microalgae-based biotechnology conjugated with innovative CRISPR/Cas9-mediated genetic engineering has been attracted much attention for the cost-effective and eco-friendly value-added compounds production. However, the discharge of reproducible living modified organism (LMO) into environmental condition potentially causes serious problem in aquatic environment, and thus it is essential to assess potential environmental risk for human health. Accordingly, in this study, we monitored discharged genetically modified microalgae (GMM) near the research complex which is located in Daejeon, South Korea. After testing samples obtained from 6 points of near streams, several green-colored microalgal colonies were detected under hygromicin-containing agar plate. By identification of selection marker genes, the GMM was not detected from all the samples. For the lab-scale environmental risk assessment of GMM, acute toxicity test using rotifer Brachionus calcyflorus was performed by feeding GMM. After feeding, there was no significant difference in mortality between WT and transformant Chlamydomonas reinhardtii. According to further analysis of horizontal transfer of green fluorescence protein (GFP)-coding gene after 24 h of incubation in synthetic freshwater, we concluded that the GFP-expressed gene not transferred into predator. However, further risk assessments and construction of standard methods including prolonged toxicity test are required for the accurate ecological risk assessment.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.1
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• pp.1-7
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• 2010

The paper proposes a multi-body dynamic simulation to numerically evaluate the generated axial force(G.A.F) and plunging resistant force(P.R.F) practically related to the shudder and idling vibration of an automobile. A numerical analysis of two plunging types of CV joints, tripod joint(TJ) and very low axial tripod joint(VTJ), is conducted using the commercial program DAFUL. User-defined subroutines of a friction model illustrating the contacted parts of the outboard and inboard joint are subsequently developed to overcome the numerical instability and improve the solution performance. The Coulomb friction effect is applied to describe the contact models of the lubricated parts in the rolling and sliding mechanisms. The numerical results, in accordance with the joint articulation angle variation, are validated with experimentation. The offset between spider and tulip housing is demonstrated to be the critical role in producing the 3rd order component of the axial force that potentially causes the noise and vibration in vehicle. The VTJ shows an excellent behavior for the shudder when compared with TJ. In addition, a flexible nonlinear contact analysis coupled with rigid multi-body dynamics is also performed to show the dynamic strength characteristics of the rollers, housing, and spider.

• Tunnel and Underground Space
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• v.14 no.2
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• pp.86-96
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• 2004

Rock mass classification methods such as RMR, Q system and GSl have been widely adopted with certain modifications for the design of mine openings. The GSI system is the only rock mass classification system that is related to Mohr-Coulomb and Hoek-Brown strength parameters and gives a simple method to calculate the engineering properties of rock masses which can be useful input parameters for a numerical analysis. A detailed surveying for GSI mapping as well as far calculating RMR values was undertaken at Daesung and Pyunghae underground limestone mining sites. RQD values were determined for row locations in these two mining sites. Based on GSI values and intact rock strength properties, the rock mass strength modulus of elasticity as well as the Mohr-Coulomb strength parameter c$_{m}$ and $\phi$$_{m}$ were determined. GSI and RMR are correlated.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.9
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• pp.103-109
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• 2003

The development of a pulse gun used for the combustion stability rating test(SRT) has been domestically tried out since the SRT should be accompanied in the process of the development of LREs. At the beginning of the development, a rupture problem of the pulse gun body had been solved by changing its material and increasing its thickness. Also, the sealing test was undertaken for a pulse gun equipped with a membrane before conducting a explosion test and by using a specially designed jig after a explosion test. Since it is appropriate to reuse the holder of a pulse gun cavity for an actual SRT, a series of experiments for several variants has been taken to make it reusable. After all, the solution for a reusable holder of a pulse gun has been found and applied for complementing its specification.

• Management & Information Systems Review
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• v.33 no.2
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• pp.119-133
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• 2014

This Research focuses on the effect of the price limits change in KOSDAQ market change on the volatility. The sample period ranges from 22 May 2000 to 24 March 2010 for daily data. We construct two subsample periods for comparing with the effect of the change of the price limit. These limits were relaxed from 12% to 15% on March 25, 2005. The first subsample period is from 25 March 2000 to 24 March 2005. The second subsample period is from 25 March 2005. to 24 March 2010. We employee four different volatility, which are the range-based volatility of Parkinson(1980; PK), Garman and Klass(1980; GK) Rogers and Satchell(1991; RS), Yang and Zhang(2008; YZ). The empirical result as follows. The major findings are summarized as follows; First, the volatility of individual stocks in KOSDAQ market reduces significantly after the price limit change. Second, There is so high volatile especially when the volatility of stock prices is high. Third, There is no meaningful relationship between volatility and market capitalization. Fourth, the more volume stocks reduce the volatility. Our results show the volatility decreased the more large volume, the more trading amount and the high price stock.

• Journal of the Korean Geotechnical Society
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• v.34 no.6
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• pp.17-24
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• 2018

In this study, static load test and dynamic load test were performed to evaluate pile-filling material (ZA-Soil) of soil-cement injected precast pile method which was developed by using the ash of circulating fluidized boiler as a stimulant for alkali activation reaction of blast furnace slag. As a result of the static load test, the allowable bearing capacity of pile was 1,350 kN, which was the same as the result of using ordinary portland cement. And total settlement was 6.97 mm, and net settlement was 1.48 mm. These are similar to the total settlement, 7.825 mm, and net settlement, 2.005 mm of ordinary portland cement. As a result of the dynamic load test and CAPWAP analysis, the skin friction was 375.0 kN, the end bearing capacity was 3,045.9 kN, and the allowable bearing capacity was 1,368.36 kN. These results are similar to the results of using ordinary portland cement as pile-filling material.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.284-289
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• 2006

Effects of mulberry fruit extract (MFE) on the levels of serum mineral and serum oxidative stress markers on 31 middle-aged humans (16 males and 15 females) supplemented with MFE for 4 weeks were investigated. Contents of mineral per 100 g MFE were 80.66 (Ca), 12.26 (Mg), 6.26 (Fe), 0.05 (Cu), and 4.04 mg (Zn). Relative scavenging activities of MFE and its cyanidin-3-glucoside on 1,1-diphenyl-2-picrylhydrazyl (DPPH) were 34 and 85%, respectively, using ascorbic acid as standard. Anthropometry measurements, serum mineral (Ca, Mg, Fe, Cu, and Zn)levels, and serum oxidative stress markers were analyzed before and after supplementation of MFE. After supplementation of MFE, no significant differences were observed in anthropometry measurements and levels of serum thiobarbituric acid reactive substance (TBARS) in males and females, and ferric-reducing ability plasma (FRAP) in males, whereas serum mineral levels (Fe in males, and Fe, Cu, and Zn in females) and serum FRAP levels (both males and females) increased significantly.

• Journal of Sensor Science and Technology
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• v.27 no.5
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• pp.317-327
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• 2018

Terahertz (THz) time-domain spectroscopy(TDS), imaging techniques, and related systems have become mature technologies, widely used in many universities and research laboratories. However, the development of creative technologies still requires improved THz application systems. A few key points are discussed, including the innovative advances of mode-locking energy-emitting semiconductor lasers and better photoconductive semiconductor quantum structures. To realize a compact, low cost, and high performance THz system, it is essential that THz spectroscopy and imaging technologies are better characterized by semiconductor and nano-devices, both static and time-resolved. We introduce the THz spectroscopy and imaging systems, the OSCAT(Optical Sampling by laser CAvity Tuning) system and the ASOPS(ASynchronous Optical Sampling) system, are constructed by our research team. We report on the THz images obtained from their use.

• Journal of Korean Medical classics
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• v.20 no.2
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• pp.231-268
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• 2007

재일본규주황한의학적전통의학지전신취시중국전통의학적지식(在日本叫做皇漢醫學的傳統醫學之前身就是中國傳統醫學的知識). 16세기이래(16世記以來), 일본불단수도이개조중국의학적최신성과(日本不斷收到而改造中國醫學的最新成果), 동양원류우부동홍류적한방의학체계점점형성적과정전후(同樣源流又不同洪流的漢方醫學體系점점形成的過程前后), 출현료4개학문유파(出現了4個學問流派). 저취시(저就是)"후세파(后世派)"."고방파(古方派)"."절충파(折衷派)"."고증파(考證派)". 소우호세파(소于호世派), 논자이경재대한한의학원전학회지적제19권3호상보고료(논者已경在大한한의학原典학회紙的第19卷3호上보告了), 본논문시연속적연구성과(本논文是연속的硏究成果). 종이재본논문상(종而在本논文上), 이한국적이정환(以한국的李政桓), 백유상(白裕相), 정창현등적연구여중국양영적연구위기초(丁彰炫等的硏究與中國梁嶸的硏九爲基礎), 요개략지보고일본의학방면상적‘고방파’(要槪略地報告日本의학方面上的'古方派'). "고방파"지칭부정근세송명의학이지지지한대장중경적"상한잡병론"지일본의가("古方派"指稱否定近世宋明醫學而只支持漢代張仲景的"傷寒雜病論"之日本醫家). 일반"상한론"전파우일본적실정시대(一般"傷寒論"傳播于日本的室町時代), 명응년간(明應年間)(1492${\sim}$1500)판정운재명유학후(阪淨運在明留학후), 타회도일본적시후(他回到日本的시候), 종명수입(종明수入)"상한잡병론(傷寒雜病論)", 이후일본후세한의칭송료이관동지역적영전덕본(以후日本후世漢醫칭송了以關東地域的永田德本)(1513-1603)위(爲)"고방파적선구자(古方派的先구者)". 도강호시대재일본학술계출현료복고사조(到江戶時代在日本學術係出現了復古思潮). 이등인제(伊藤仁劑)(1627${\sim}$1705)앙망료유학적경전(仰望了儒學的經典), 이차적극지주장료의학적복고(而且積極地主張了醫學的復古), 이후적생조래(以후荻生組徠)(1666${\sim}$1728)대우복여성인적학문부단노력(對于復與聖人的學問不斷努力). 인차복고적학문재덕천시대성위일대학파(因此復古的學問在德川時代成爲一代學派), 18세기상반기시전성시기(18世紀上半期是全盛시期). 주요의가시명고옥현의(主要醫家是名古屋玄議)(1628${\sim}$1696), 후등양산(後藤양山)(1659${\sim}$1733), 산협동양(山脅東洋), 병하천민(병河天民)(1679${\sim}$1719), 송원유악(松原維嶽)(1689${\sim}$1765), 향천수암(香川修庵)(1683${\sim}$1755), 타문복고적유학영향도흔다의학방면(他문復古的儒學影향到흔多의학方面). 중요의가길익동동(重要醫家吉益東洞)(1702${\sim}$1773)도후대피평위고방적'태두'(到后代被평위古方的'泰斗'), 동시'마귀'(同시'魔鬼'). 인차본논문소우황한의학지중"후세파"여반대후세파적"고방파"(因此本論文소于皇漢醫學之中"后世派"與反대后世派的"古方派"), 통과학파명칭여역사지위(通過學派名稱與歷史地位), 주요의가적생애(主要醫家的生涯), 학술적요지(學術的要旨), 저서등(著書等), 이연구병보고타문적학문주장(以硏究병報告他們的學問主張). 이차진저차궤회(而且진저次机회), 상회고아문한의학연착여하역사적궤적(想回고我문韓醫學沿着如何歷史的軌跡).