• Restorative Dentistry and Endodontics
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• v.36 no.1
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• pp.37-49
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• 2011

Objectives: The aim of this study was to evaluate the surface color of indirect resin restoration according to the layering placement of different shade of incisal composite. Materials and Methods: In this study, CIE $L^*a^*b^*$ value of 16 Body composite of Tescera ATL (Bisco, Schaumburg IL,USA) was measured by spectrophotometer (NF999, Nippon Denshuku, Japan), and compared to CIE $L^*a^*b^*$ value of Vitapan shade guide. Nine shade Incisal composite of Tescera ATL were buildup to 1 mm thickness on Body composites inlay block, and CIE $L^*a^*b^*$ value was measured. Incisal composite was ground to 0.5 mm thickness and CIE $L^*a^*b^*$ value was re-measured. Color difference between Body composite and Incisal composites layered on Body composite was calculated as a function of thickness. Results: Color difference between corresponding shade of Tescera Body composite and Vitapan shade guide was from 6.88 to 12.80. $L^*$ and $b^*$ value was decreased as layering thickness of Incisal composite on Body composite was increased. But, $a^*$ value did not show specific change tendency. Conclusions: Surface color difference between Body composites and Incisal composites layered on Body composite was increased as the layering thickness of Incisal composite increased (p < 0.05).

• Journal of Korean Society of Forest Science
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• v.90 no.6
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• pp.699-706
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• 2001

This study was conducted to evaluate the effectiveness of basic oxygen furnace (BOF) slag as soil conditioner in a nursery and two natural forests. The BOF slag was applied at rates of 0, 4, 8, and 12 t/ha for seedbed nursery of three tree species-Pinus densiflora, Larix leptolepis and Amorpha fruticosa; and 0, 10, 20, and 40 t/ha for Pinus densiflora natural forests located at two sites. In case of the nursery study, the significant increase in soil pH and contents of Ca, Mg, $SiO_2$, Fe and Mn was noticed after six months of the BOF slag application. Dry weight of Pinus densiflora seedlings with BOF slag treatments was lower compared with that of control. There were no significant differences among treatments in dry weight of Larix leptolepis seedlings. Dry weight of Amorpha fruticosa seedlings, which are deciduous species and grow rapidly at seedling stage, increased significantly and T/R ratio decreased as BOF slag rate increased. The differences of effects of BOF slag application on the seedlings of tree species may be attributed to the differences of optimum pH range of the species. In Pinus densiflora natural forests, there were no significant differences in soil pH and contents of $SiO_2$, Fe and Mn among the treatments, but these values became higher as BOF slag rate increased. Contents of Ca in soil became significantly higher as BOF slag rate increased. There were no significant differences among treatments in net production of mature Pinus densiflora trees, but BOF slag rate of 10ton/ha showed the highest net production. Young Pinus densiflora trees at the plots of BOF slag rate of 10 t/ha showed significantly higher root collar diameter growth rate and twig net production than those of other treatments. It may be given as a conclusion that BOF slag application in nursery and forest soil increased soil pH and contents of Ca, $SiO_2$, Fe and Mn in soil and they showed the ability of BOF slag to be used as a soil conditioner in strongly acid soil.

• Journal of Korean Classical Literature and Education
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• no.35
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• pp.87-122
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• 2017

1) The passage "Sila seongdae so-seongdae cheonha daepyeong nahu-deog (新羅盛(聖)代 昭盛代 天下大平 羅侯德)" of the Korean Dynasty , corresponds to the primary passage of Cheonyong Rang Manghaesa(처용랑 망해사)>. These passages are ironic expressions of King Heongang's reign. This passage can therefore be interpreted as having the meaning of "People talk about King Heongang who ruined the kingdom. The bright politics of Silla's loyalty is the virtue of King Heongang." 2) "Cheoyong aba isi insaeng-ae sangbuleo hasilandae isi insaeng-ae samjaepalnan-i ilsi somyeol hasyatda (處容 아바 以是人生애 相(常)不語시란 以是人生애 相(常)不語시란 三災八難이 一時消滅샷다)." This was said by Cheoyong(처용), who was unable to reveal his anger while witnessing his wife being raped by Yuk-sin(疫神). This passage means, "Father Cheoyong(처용), in this world if a man does not express anger about the absurdity of the world, he can escape from catastrophe," or, "Father Cheoyong (처용), because in this world you had not expressed anger about the absurdity of world, you could escape from catastrophe." 3) In "maa-man maa-man haniyeo sibi jegug-i moda jiseo syeon aeu cheoyongbi-hal maa-man haniyeo (마아만 마아만 니여 十二諸國이 모다 지 셰온 아으 處容아비 마아만 니여)," the most likely interpretation of Maa is "마아(麻兒)," which means "scarecrow." In this way, this passage emphasizes that Cheyong(처용) is not a scarecrow, but a representative of the eyes of all people in all kingdoms. 4) In "meoja oeyaja logliya ppallina nae singohal maeyara (머자외야자 綠李야 리나 내 신고 야라", meoja (머자) is the double arranging shape of meotda(멎다), and oeyaja(외야자) is the double arranging shape of oeda(외다); those characters mean "ugly" and "wrong for each other." Additionally, Rokri(綠李) can be regarded as an administrator in blue or black clothes who is performing an errand of the yuksin(疫神).

• Journal of Food Hygiene and Safety
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• v.34 no.5
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• pp.447-453
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• 2019

In this study, the contamination of 4 types of heavy metals (lead, cadmium, arsenic, and mercury) was monitored in 80 seaweeds and their processed products, and a food safety assessment was also carried out for these heavy metals. Lead, cadmium and arsenic were analyzed by ICP-OES and mercury was analyzed by mercury analyzer. The detection ranges of heavy metals were found as follows: Pb (N.D-0.802 mg/kg), Cd (N.D-0.759 mg/kg), As (0.134-17.296 mg/kg), and Hg (0.0005-0.0331 mg/kg). Pb and Hg showed no significant differences among seaweeds whereas Cd and As were significantly higher in the species hizikia fusiforme (P<0.05). Food safety assessment from seaweed intake was measured by PTWI (Provisional Tolerable Weekly Intake), PTMI (Provisional Tolerable Monthly Intake), and MADL (Maximum Allowable Daily Body Load) as set by JECFA (Joint FAO/WHO Expert Committee on Food Additives). Pb and Hg were 0.197%, 0.036% of PTWI respectively, while Cd was 1.877% of PTMI and As was 0.619% of MADL. Therefore, it was found that heavy metal levels of seaweed were low and was considered to be safe for consumption.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.6
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• pp.427-446
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• 2008

A review on the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering in 2006 has been accomplished. Focus has been put on current status of research in the aspect of heating, cooling, ventilation, sanitation and building environments. The conclusions are as follows. (1) The research trends of fluid engineering have been surveyed as groups of general fluid flow, fluid machinery and piping, etc. New research topics include micro heat exchanger and siphon cooling device using nano-fluid. Traditional CFD and flow visualization methods were still popular and widely used in research and development. Studies about diffusers and compressors were performed in fluid machinery. Characteristics of flow and heat transfer and piping optimization were studied in piping systems. (2) The papers on heat transfer have been categorized into heat transfer characteristics, heat exchangers, heat pipes, and two-phase heat transfer. The topics on heat transfer characteristics in general include thermal transport in a cryo-chamber, a LCD panel, a dryer, and heat generating electronics. Heat exchangers investigated include pin-tube type, plate type, ventilation air-to-air type, and heat transfer enhancing tubes. The research on a reversible loop heat pipe, the influence of NCG charging mass on heat transport capacity, and the chilling start-up characteristics in a heat pipe were reported. In two-phase heat transfer area, the studies on frost growth, ice slurry formation and liquid spray cooling were presented. The studies on the boiling of R-290 and the application of carbon nanotubes to enhance boiling were noticeable in this research area. (3) Many studies on refrigeration and air conditioning systems were presented on the practical issues of the performance and reliability enhancement. The air conditioning system with multi indoor units caught attention in several research works. The issues on the refrigerant charge and the control algorithm were treated. The systems with alternative refrigerants were also studied. Carbon dioxide, hydrocarbons and their mixtures were considered and the heat transfer correlations were proposed. (4) Due to high oil prices, energy consumption have been attentioned in mechanical building systems. Research works have been reviewed in this field by grouping into the research on heat and cold sources, air conditioning and cleaning research, ventilation and fire research including tunnel ventilation, and piping system research. The papers involve the promotion of efficient or effective use of energy, which helps to save energy and results in reduced environmental pollution and operating cost. (5) Studies on indoor air quality took a great portion in the field of building environments. Various other subjects such as indoor thermal comfort were also investigated through computer simulation, case study, and field experiment. Studies on energy include not only optimization study and economic analysis of building equipments but also usability of renewable energy in geothermal and solar systems.

• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.630-647
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• 2021

We determined the current problem of the restoration deposit-estimation system, stipulated by the Mountainous Districts Management Act, using the Delphi technique. Consequently, we proposed a standard model for forest land restoration to derive a reasonable deposit-estimation system. With the result of the Delphi survey, the inappropriateness of land-use type and slope gradient classifications was shown; the insufficiency of standard works was a significant problem in the current system. A way to solve these problems was devised, to reorganize the current land-use type into the subject of the site. The specific subjects included the following: (i) to permit or report forest land-use change and temporary use of forest land, (ii) to report temporary use of forest land, (iii) to permit stone collection or sale for mineral mining, and (iv) to allow sediment collection. The current slope gradient subdivision into (a) θ<10°, (b) 10°≦θ<15°, (c) 15°≦θ<20°, (d) 20°≦θ<25°, (e) 25°≦θ<30°, and (f) θ≧30° and the reorganization of 17 standard works into 22 standard works were deemed as solutions, along with seven additional works. We developed 24 standard models for the forest land restoration project based on the aforementioned results. The deposits estimated by these models ranged from 34,185,000 (Korean) won to 607,403,000 won. If additional works, premiums, discounts, and supervision fees are added to the models, the deposit increases to an estimated 668,143,000 won subject to permission for stone collection or sale and mineral mining. Experts agree on the distribution of the restoration deposits estimated by these models at a high level in the Delphi survey. Our findings are expected to contribute to securing the appropriateness of the restoration cost deposited for the smooth performance of the vicariously executed restoration project.

• Journal of vocational education research
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• v.30 no.4
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• pp.23-49
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• 2011

Faculty performance evaluation system has been settled down as an uncomfortable but unavoidable system, and it is one of the most important factors to grow the college competitiveness up. In this study, we selected and surveyed faculty evaluation models of several universities and colleges in Korea, and analyzed by comparing each evaluation areas of educational achievement, college-industry collaboration, research, and service. We also identified the properties of the current faculty evaluation models of the junior colleges, and derived several problems from these models such as an imitation of four-year university model, a disorders of job evaluation with respect to the attributes of classified jobs, a large variation of individual item weights, and an insufficient reflection of major characteristics. Based on these surveys and analysis, an improved faculty evaluation model for the junior college is proposed in this study. This model proposed four basic areas-educational achievement, college-industry collaboration, research, and service by considering the importance of the college-industry collaboration in the junior college-as well as the team evaluation area. Weights of the SCI-class paper was selected as a criterion for the arrangement of objective comparison of each evaluation items. We showed the integration method of several different evaluation model with respect to the attributes of classified jobs of each faculties, and evaluation plan of variational characteristics according to the majors of individuals in this model. Finally, we introduced an area fail and rating system to operate efficiently the proposed faculty evaluation model.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.600-605
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• 2010

'Dagreen' (Scale cereal L.), a new rye variety was developed from the open pollination among 10 rye lines at the National Institute of Crop Science in 1995 and mass selection were made at National Institute of Crop Science from 1996 to 1999. Recurrent selections were made at Dept. Rice and Winter Cereal Crop, NICS, RDA from 2000 to 2006. This new variety has erect plant type with medium size pale green leaves. The number of spike per $m^2$ was 713 and the plant height was 103cm. The heading date of 'Dagreen' was April 24 which was 7 days earlier than that of "Koolgrazer". It was adaptable for forage use at an early stage as a whole crop. Lodging resistance was higher than that of check variety 'Koolgrazer'. The chemical components and quality of forage showed 10.2 % crude protein, 36.6 % ADF, 62.4 % NDF and 59.9 % TDN. 'Dagreen' showed high resistance to powdery mildew and leaf rust than those of check variety in the field condition. The average dry matter (7,010kg $ha^{-1}$) of 'Dagreen' harvested at April 28 were 6 % higher than 'Koolgrazer'. This variety is recommended for all of the rye cultivation area in Korea.

• Journal of The Korean Astronomical Society
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• v.52 no.1
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• pp.11-21
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• 2019

Intensive Monitoring Survey of Nearby Galaxies (IMSNG) is a high cadence observation program monitoring nearby galaxies with high probabilities of hosting supernovae (SNe). IMSNG aims to constrain the SN explosion mechanism by inferring sizes of SN progenitor systems through the detection of the shock-heated emission that lasts less than a few days after the SN explosion. To catch the signal, IMSNG utilizes a network of 0.5-m to 1-m class telescopes around the world and monitors the images of 60 nearby galaxies at distances D < 50 Mpc to a cadence as short as a few hours. The target galaxies are bright in near-ultraviolet (NUV) with $M_{NUV}$ < -18.4 AB mag and have high probabilities of hosting SNe ($0.06SN\;yr^{-1}$ per galaxy). With this strategy, we expect to detect the early light curves of 3.4 SNe per year to a depth of R ~ 19.5 mag, enabling us to detect the shock-heated emission from a progenitor star with a radius as small as $0.1R_{\odot}$. The accumulated data will be also useful for studying faint features around the target galaxies and other science projects. So far, 18 SNe have occurred in our target fields (16 in IMSNG galaxies) over 5 years, confirming our SN rate estimate of $0.06SN\;yr^{-1}$ per galaxy.

• Korean Journal of Microbiology
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• v.55 no.3
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• pp.274-277
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• 2019

Ruminococcus sp. KGMB03662 was isolated from fecal samples obtained from a healthy Korean. The whole-genome sequence of Ruminococcus sp. KGMB03662 was analyzed using the PacBio Sequel platform. The genome comprises a 2,707,502 bp chromosome with a G + C content of 43.09%, 2,484 total genes, 2,367 protein-coding gene, 14 rRNA genes, and 53 tRNA genes. In the draft genome, genes involved in the hydrolysis enzyme, fatty acid biosynthesis, fatty acid metabolite, antibiotic biosynthesis, and antibiotic resistance have been identified. Those genes of KGMB03662 may be related to the regulation of human health and disease.