• Journal of the Korea Concrete Institute
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• v.29 no.2
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• pp.141-148
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• 2017

This study is experimentally investigated the effects of various steam curing parameters on the early-age compressive strength development of high strength concrete (over 40 MPa) in the precast plant production. High strength concrete are used only ordinary portland cement (type I) and water-cement ratio selected 3cases (25%, 35% and 45%). Also, steam curing parameters are as followings ; (1) Preset period 2cases (3 hours and 6 hours) (2) Maximum curing temperature 3cases ($45^{\circ}C$, $55^{\circ}C$ and $65^{\circ}C$) (3) Maintenance time of curing temperature 3cases (4 hours, 6 hours and 8 hours) (4) Maximum rate of heating and cooling $15^{\circ}C$/hr. Initial setting time and adiabatic temperature rising ratio of these concrete according to water-cement ratio are tested before main tests and examined the compressive strength development for the steam curing parameters. Also compressive strength are compared with optimum steam curing condition and standard curing at test ages. As test results, the optimum steam curing conditions for high strength concrete(over 40 MPa) are as followings. (1) Preset period ; over initial setting time of concrete (2) Maximum curing temperature ; bellow $55^{\circ}C$ (3) Maintenance time of curing temperature ; bellow 6hours. Also strength development of steam curing concrete show in the reversed strength at 28 days. It is to propose an efficient steam curing condition for high strength concrete in the precast method.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.3243-3254
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• 2013

It is well known that increased incidences of lung, skin, and bladder cancers are associated with occupational exposure to PAHs. Animal studies show that certain PAHs also can affect the hematopoietic and immune systems and can produce reproductive, neurologic, and developmental effects. As a consequence, several studies have been attempted to investigate the fate of PAHs in atmospheric environment during the past decades. However, there is still a lack of information in regard to the atmospheric concentration of PAHs during the "Bon Fire Night". In this study, twenty-three polycyclic aromatic hydrocarbons and twenty-eight aliphatics were identified and quantified in the $PM_{10}$ and vapour range in Birmingham ($27^{th}$ November 2001-$19^{th}$ January 2004). The measured concentrations of total particulate and vapour (P+V) PAHs were consistently higher at the BROS in both winter and summer. Arithmetic mean total (P+V) PAH concentrations were $51.04{\pm}47.62$ ng $m^{-3}$ and $22.30{\pm}19.18$ ng $m^{-3}$ at the Bristol Road Observatory Site (BROS) and Elms Road Observatory Site (EROS) respectively. In addition arithmetic mean total (P+V) B[a]P concentrations at the BROS were $0.47{\pm}0.39$ ng $m^{-3}$ which exceeded the EPAQS air quality standard of 0.25 ng $m^{-3}$. On the other hand, the arithmetic mean total (P+V) aliphatics were $81.80{\pm}69.58$ ng $m^{-3}$ and $48.00{\pm}35.38$ ng $m^{-3}$ at the BROS and EROS in that order. The lowest average of CPI and $C_{max}$ measured at the BROS supports the idea of traffic emissions being a principle source of SVOCs in an urban atmosphere. The annual trend of PAHs was investigated by using an independent t-test and oneway independent ANOVA analysis. Generally, there is no evidence of a significant decline of heavier MW PAHs from the two data sets, with only Ac, Fl, Ph, An, 2-MePh, 1+9-MePh, Fluo and B[b+j+k]F showing a statistically significant decline (p<0.05). A further attempt for statistical analysis had been conducted by dividing the data set into three groups (i.e. 2000, 2001-2002 and 2003-2004). For lighter MW compounds a significant level of decline was observed by using one-way independent ANOVA analysis. Since the annual mean of $O_3$ measured in Birmingham City Centre from 2001 to 2004 increased significantly (p<0.05), it may be possible to attribute the annul reduction of more volatile PAHs to the enhanced level of annual average $O_3$. By contrast, the heavier MW PAHs measured at the BROS did not show any significant annual reduction, implying the difficulties of 5- and 6-ring PAHs to be subject to photochemical decomposition. The deviation of SVOCs profile measured at the EROS was visually confirmed during the "Bonfire Night" festival closest to the $6^{th}$ November 2003. In this study, the atmospheric PAH concentrations were generally elevated on this day with concentrations of Fl, Ac, B[a]A, B[b+j+k]F, Ind and B[g,h,i]P being particularly high.

• Journal of Korean Medical classics
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• v.22 no.3
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• pp.31-51
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• 2009

The characteristics of Jin's ideas on clinic theory can be arranged as follows. 1. Jin emphasized warming and tonifying[溫補] in treatment and the part that shows this the best is the taking care of[調理] the Vital gate[命門], kidney, liver, and spleen. His ideas were based on his understanding of a human life's origin, and was influenced by Seolgi(薛己), Joheon-ga(趙獻可) and Janggaebin(張介賓)'s Vital gate and source Gi theory(元氣說) so scholastically, he has that in common with them but was later criticized by later doctors such as Oksamjon(玉三尊) as an 'literary doctor(文字醫)' who followed the ideas of "Uigwan(醫貫)". 2. The warming and tonifying school[溫補學派], who were influenced by Taoism, said in their theory of disease outbreak[發病學說] that since one must not hurt one's Yin essence and Yang fire [陰精陽火] there is more deficiency than excess, so that was why they used tonifying methods. Jin was also like them and this point of view is universal in internal medicine, gynecology, pediatric medicine and surgery and so on. 3. Jin, who saw the negative form of pulse diagnosis[診脈] emphasized following symptoms over pulse diagnosis using the spirit of ‘finding truth based on truth[實事求是]' in "Maekgyeolcheonmi(脈訣闡微)", but emphasized 'the combination of pulse and symptoms[脈證合參]'. He understood pulse diagnosis as a defining tool for symptoms, and in "Seoksilbirok(石室秘錄)" simplified pulse diagnosis into 10 methods : floating/sunken(浮沉), slow/fast(遲數), large/fine(大小), vacuous/replete(虛實) and slippery/rough(滑澀). 4. Jin used 'large formulas(大方)' a lot that usually featured a large dose, and in " Bonchosinpyeon(本草新編)" he thought of the seven formulas(七方) and ten preparations(十劑) as the standard when using medicine. He did away with old customs and presented a 'new(新)' and 'extra(奇)' point of view. He especially used a lot of Insam(人蔘) when tonifying Gi and Geumeunhwa(金銀花) when treating sores and ulcers. 5. In the area of surgery Jin gave priority to the early finding and treatment of disease with internal treatment[內治] and was against the overuse of acupuncture. However records of surgical measures in a special situation like lung abscesses(肺癰) and liver abscesses(肝癰), and anesthetic measures using 'Manghyeongju(忘形酒)' and 'Singoiyak(神膏異藥)' and opening the abdomen or skull, and organ transplants using a dog's tongue are important data. 6. Jin stated the diseases of Gi and blood broadly. Especially in the principles of treating blood, blood diseases had to be forwarded[順] and Gi regulation[理氣] was the number one priority and stated the following two treatments. First, in "Jeonggiinhyeolpyeon(精氣引血篇)" of volume 6 of "Oegyeongmieon(外經微言)", for the rules for treating blood he stated the pattern identification of finding Gi in blood and blood in Gi. Second, he emphasized Gi regulation(理氣) in blood diseases and stated that the Gi must be tonifyed after finding the source of the loss of blood.

• Analytical Science and Technology
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• v.13 no.5
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• pp.608-615
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• 2000

A determination method of trace nickel and cobalt in water samples was studied and developed by adsorbing their complexes on ion exchange resin suspension. The analytical ions were formed as complexes with a ligand of APDC (ammonium pyrrolidinedithiocarbamate) and adsorbed on anion exchange resin of Dowex 2-X8. After the suspension was filtered out with membrane filter, the complexes were dissolved in HCl solution by an ultrasonic vibrator for ET-AAS determination. Several conditions were optimized as followings. pH of sample solution: 5.0, amount of ligand APDC: more than 430 times in mole ratio, the type and concentration of acid: 0.1 M HCl, and vibration time: 7 minutes. The addition of palladium in the HCl solution could improve the reproducibility and sensitivity by a matrix modification in the absorbance measurement. This procedure was applied for the analysis of three kinds of real water samples. The detection limits equivalent to 3 times standard deviation of blank were Co 0.36 ng/mL and Ni 0.27 ng/mL and recoveries in spiked samples were 99-102% for cobalt and 100-105% for nickel.

• Applied Chemistry for Engineering
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• v.7 no.3
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• pp.588-596
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• 1996

The optimum conditions of the 1st and 2nd distillation had been investigated to obtaine a high quality monomeric MDI and fire reactive polymeric MDI by purification of crude MDI. Effect of additives on the monomeric MDI's color change, dimerization and the reactivity of polymeric MDI with standard polyol system has been tested. When the monomeric MDI yield is approximately 32%, 4,4'-MDI content is above 98% in the monomeric MDI at the 1st distillation. When the separation ratio of initial portion and residue percentage, reflux ratio are set at respectively, approximately 20wt%, 9wt%, above 2 in order to minimize the content of 2,4'-MDI in monomeric MDI, the freezing point of final distilled monomeric MDI is above $38.4^{\circ}C$. Since the monomeric MDI is inherently unstable in the room condition, monomeric MDI easily changes it's color and conducts self-polymerization reaction. To increase the stability of monomeric MDI, the composition of antioxidant, which is composed of phenolic 1st antioxidant, phosphorus 2nd antioxidant, UV absorbent and Hindered amine light stabilizer are used, and benzoyl chloride as antipolymerization agent test are that APHA color is less than 20, dimer content is remained less than 0.36wt% after 45 days storage of monomeric MDI.

• Journal of Korean Society of Forest Science
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• v.99 no.3
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• pp.391-396
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• 2010

To analyze the characteristics of canopy fuel in Pinus densiflora stand, which is essential to assess the crown fire hazard, allometric equations for estimation of crown fuel biomass were developed by subjectively categorized crown fuel component and crown bulk density was analyzed by available fuel component categories. Ten trees were destructively sampled at Pinus densiflora stand in Mt. Palgong in Daegu and their crown fuels were weighed separately for each fuel category by size classes and by living and dead. Regression equations that estimate crown fuel load by diameter at breast height(D) or additional total height(H) were derived. The adjusted coefficient of determination values were the highest (${R^2}_{adj}$=0.835-0.996) and standard error of estimate were the lowest (SEE=0.074-0.638) in the allometric equation lnWt=${\alpha}+{\beta}lnD+{\gamma}lnH$ in average. However, in needles and small branches categories, the differences in ${R^2}_{adj}$ and SEE between equations were not significant. Crown bulk density (CBD), which was calculated by crown fuel load divided by crown volume, was 0.067 kg/$m^3$ in average when only needles were considered as available crown fuel and 0.097 kg/$m^3$ when needles and branches (0-0.5 cm diameter) were considered. The increments of CBD of needles and small branches were little even when diameter at breast height increased.

• Journal of Haehwa Medicine
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• v.13 no.2
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• pp.205-212
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• 2004

Now many sustitution and false articles is used in korea instead of heshouwu. To use heshouwu correctly, we will make a quilitative certificational plan of heshouwu to investigate all of lieraturea, records and documents. And we could reach conclusions as folloews. 1) Source of plant Heshouwu is a root tuber of a perennial herb Polygonum multiflorum Thunberg(Family : Polygonaceae). 2) Harvest After planting 3-5 yaers, harvesting in an autumn, washin clean the mud, a big heshouwu cut off a half or section, dry in sunny place or at a little fire. When harvesting, we harvest only a big thing, a small thing transfer a field, after culturing of 1-2 years, harvest at big roots. Harvesting is done usually in an autumn after 3 years. When collecting a seed, we must harvest a heshouwu the next year. 3) Process We must process heshouwu at the decoction of black beans, heshouwu suck in the decoction of black beans, heat with steam in an iron pot. Black beans is used every 100 kg of heshouwu. 4) Quility (1) Funstional standards It is good that weight is heavy and outer skin is yellow-brown, section surface is light red color, powdery and has a figure such as clouds in section. (2) Physicochemical standards Heshouwu expesses a various chang of components in process of working. We think that it need to add a standard of detection about 2,3,5,4'-tetrahrdroxystilbene-2-O-${\beta}$ -D-glucoside in a current authentic document which is a water-soluble component of heshouwu. It must that Dry on loss is less than 14.0%, content of ash is less than 5.0%, Content of acid-nonsoluble ash is less than 1.5%, Content of extract is more than 17.0%. A fixed quantity of 2,3,5,4'-tetrahrdroxystilbene-2-O-${\beta}$ -D-glucoside is more than 1.0%. Contens of heavy metal has to detect less than 30 ppm and there is no reminding agriculural medince.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.12 no.2
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• pp.99-107
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• 1998

This dissertationhas confirmed the non-flam mability of cast mold transformer that is increasingly used lately. As a research progress, the investigation has been performed on the installation status and each line of the subway system which have the most mold transformer accidents, and the impediment status of the transformer for rectifier and the high-voltage distribution transformer per each manufacturer. Then, a high voltage mold of the actual mold transformer has been installed in the horiwntal heating furnace and the heat has been applied by the standard heating temperature curve of KSF 2257(Fireproof testing meth od of the construction structures: 1993). Accordingly, the combustibility of the mold transformer based on the test results has been found that 78 minutes has been required for the complete burning per the KSF 2257 combustion test curve and that, after stopping the heat application of the horizontal furnace after ignition, the flame progress has not been made but shown as the self-extinguishing characteristics when the flame progress has been checked. Thus, the non-flammability and self-extinguishability of the mold transformer have been confirmed. The result of this dissertation has indicated that the accident involving mold transformer has been progressed and expanded by the dielectric breakdown or void due to the crack in the mold rather than a fire accident caused by a short-circuit or an overload.r an overload.

• Journal of the Korea Society for Simulation
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• v.21 no.1
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• pp.81-88
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• 2012

In the M&S filed, The Battle Lab is available for acquisition, design, development tool, validation test, and training in the weapon system of development process. Recently, the Battle Lab in the military of Korea is still in an early stage, in spite of importance of battle lab construction. In the environment of network centric warfare, a practical use of the M&S which is connecting live, virtual and constructive model can be applied to all field of System Engineering process. It is necessary thar the Battle Lab is not restricted by time and space, and is possible for the technical implementation. In this paper, to guarantee the interoperability of live and virtual simulation, virtual simulators connect live simulators by using the tactical data link. To guarantee the interoperability of virtual and constructive simulation, both virtual simulators and constructive simulators use the RTI which is the standard tool of M&S. We propose the System that constructed the Air Defence Battle Lab. In case of the approach of target tracks, The Air Defence Battle Lab is the system for the engagement based on a command of an upper system in the engagement weapon system. Constructive simulators which are target track, missile, radar, and launcher simulator connect virtual simulators which are MCRC, battalion, and fire control center simulators using the RPR-FOM 1.0 that is a kind of RTI FOM. The interoperability of virtual simulators and live simulators can be guaranteed by the connection of the tactical data links which are Link-11B and ATDL-1.

• The Journal of the Convergence on Culture Technology
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• v.6 no.4
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• pp.331-337
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• 2020

The study analyzes the appropriate number of people per a household by applying an evacuation simulation to a 27-floor apartment in accordance with the NFPA 101 standard. The results of the analysis are as follows. First, if there are three people residing in each household, there would be 156 households in total, of which 85.25% were evacuated within 5 minutes. Second, 208 households with 4 residents were evacuated within 5 minutes. Third, if there are five people residing in each household, there would be a total of 260 households and 71.92% of residents were evacuated within 5 minutes. Lastly, 62.82% of the 312 households, each consisting of 6 people, were evacuated within 5 minutes. Measures to reduce evacuation time include determining the width of the stairs according to the number of people indoors, the number of floors in the building, the slope of stairs, and the users' characteristics, the design reflecting the ventilation conditions of the stairs, the installment of outdoor evacuation stairs, two-way stairs, evacuation lift, and the installation of an evacuation safety zone for people to evacuate outside of the building in the middle floors. In addition, measures, such as the mandatory installation of automatic emergency door open-close device to the rooftop, are required to facilitate rooftop evacuation.