• 보존과학회지
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• 제26권4호
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• pp.385-395
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• 2010

이 연구는 현풍석빙고의 미기후 특성을 분석하여 손상에 영향을 미친 기후인자를 해석하고 보존환경을 평가한 것이다. 석빙고의 내부 구성부재에는 균열, 이격, 탈락, 박락, 백화, 갈색 변색, 흑색 변색 및 생물에 의한 변색이 발생하였으며, 이 중 생물에 의한 변색이 가장 높은 훼손율(24%)을 보였다. 석빙고 내부의 환경은 외부의 기상 변화에 따라 변동하나 변동폭과 일교차가 작고 일정한 온습도를 유지하는 것으로 나타났다. 이는 석빙고 전면의 산사면과 폐쇄된 입구환경이 외기를 차단하여 온습도의 변화를 최소화하였기 때문이다. 석빙고의 단열환경은 수분의 응축과 동결 현상을 방지하여 물리적 손상도를 저감하고 장빙기능을 극대화한 것으로 판단된다. 그러나 99% 이상의 높은 상대습도는 미생물의 생장을 활성화시켜 생물학적인 손상도를 높인 것으로 해석된다.

• 한국약용작물학회지
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• 제1권2호
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• pp.158-161
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• 1993

본(本) 시험(試驗)은 1992년 충남(忠南) 농촌진흥원(農村振興院) 특작(特作) 시험포장(試驗圃場)에서 수행된 결명(決明) 적기파종(適基播種) 구명(究明)과 피복재료(被覆材料) 선발(選拔) 결과(結果)는 다음과 같다. 1. 대전 중부지역 결명 파종적기는 5윌 18일 파종이 가장 수량이 많았고, 6윌 하순도 10a당 273kg까지 생산이 가능하여 맥후작으로 이용할시 유리한 작물로 사료되었다. 2. 피복 재료 선발은 무피복대비 전구에서 수량성에 유의성이 인정되지 않았으나, 관행(무피복)보다 수량이 $20{\sim}53%$ 증수되었고 흑색 PE는 잡초제거 노력을 경감하여 생력화 할 수 있었다. 3. 결명은 조기파종시 결명 입고병이 조금 발생할뿐 파종기, 피복재료에 관계없이 농약사용없이 무공해 농산물이 생산 가능하였다.

• 한국해양공학회지
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• 제27권5호
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• pp.10-15
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• 2013

The crack-healing behavior and corrosion resistance of SiC ceramics were investigated. Heat treatments were carried out from $900^{\circ}C$ to $1300^{\circ}C$. A corrosion test of SiC was carried out in acid and alkaline solutions under KSL1607. The results showed that heat treatment in air could significantly increase the strength. The heat-treatment temperature has a profound influence on the extent of crack healing and the degree of strength recovery. The optimum heat-treatment temperature was $1100^{\circ}C$ for one hour at an atmospheric level. In the two kinds of solutions, the cracks in a specimen were reduced with increasing time, and the surface of the crack healed specimen had a greater number of black and white spots. The strength of the corroded cracked specimen was similar to that of the cracked specimen. The strength of the corroded crack healed specimen decreased 47% and 75% compared to that of the crack healed specimen in the acid and alkaline solutions, respectively. Therefore, the corrosion of SiC ceramics is faster in an alkaline solution than in an acid solution.

• 대순사상과 동아시아종교
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• 제3권2호
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• pp.71-92
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• 2024

The world we live in is becoming more convenient thanks to the inventions of science and technology. Still, the world is also becoming more and more unpredictable with the current situation of VUCA (Volatility, Uncertainty, Complexity, Ambiguity). The Covid-19 pandemic brought the biggest global disaster ever with 774,631,444 infected people and 7,031,216 deaths (WHO on February 11, 2024) but it seems that humanity is gradually forgetting this disaster. Meanwhile the economic stimulus packages worth trillions of dollars from governments after the pandemic have further caused the world debt bubble to swell. The bubble burst scenario is something that many economic experts fear. Apparently, in the transitional period of the early decades of the 21st century, the world's economic, cultural, political, social, natural, and environmental aspects have undergone profound transformations: from the real estate and finance crises in the United States since 2008; through the melting of the Arctic ice over the past several decades; to the double disaster of the earthquake and tsunami in Japan in 2011. Especially, in the context of the world economic crisis after the COVID-19 pandemic, the human achievements of the past thousands of years are in jeopardy of being wiped out in an instant. Many people are predicting a bad scenario for a chain collapse. Facing the signals of an imminent economic catastrophe based on the appearance of "the Gray Rhino, Black Swan and White Elephant," many drawn in by Eschatological thought declare that Doomsday will occur shortly. This is the time for many other people to hope for the incoming Messiah. The Messiah is said to appear when people feel despair or suffer a great disaster because faith in the Savior can help them overcome adversity mentally. This research will find out how adherents of Buddhism view and deal with civilizational crises by examining history via symbols associated with Maitreya as based upon the Buddhist Messiah, Maitreya.

• 한국환경보건학회지
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• 제40권2호
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• pp.147-156
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• 2014

Objectives: This study was carried out to examine whether the apparent photolysis with or without sensitizers [NaOH and humic acid (HA)] was prompted photodegradation of polychlorinated biphenyl (PCB) in aqueous solution. Methods: PCBs photodegradation occurred using fluorescence black lamps at ${\lambda}_{max}=300nm$. PCB congeners were exposed in 10 ppm HA or 0.05N NaOH solutions, to investigate the decreasing profile of PCB concentration with time. The PCBs were then analyzed by gas chromatography/mass spectrometry (GC-MS). Reductive degradation profile of PCB congeners in the presence of both sensitizers under oxygen-saturated protic conditions was described using the wind-rose diagrams. Results: Use of HA or NaOH decreased PCB concentration with time in the dark and on irradiation, indicating that photolysis underwent through reductive dechlorination through energy transfer and possibly with reactive oxygens. The dechlorination was marked by a chromatographic shift, observed in the GC-MS plots. Therefore it is logical to assume that increasing the dose of sensitizers would increase the photodegradation rates of PCBs. The half-lives of pentachloro-PCB (penta-3) in 0.05N NaOH and 10 ppm HA were estimated at about 47 hours and 39 hours, respectively, under the same experimental conditions of photolysis. It was found that the rate of photolysis of pentachloro-PCB in aqueous solution followed apparent first-order kinetics compared to other congeners. Conclusion: Photochemical degradation (using 328 nm UV light) of penta- and hexa-PCBs in HA or alkaline solution is a viable method for pretreatment method. The results are helpful for the further comprehension of the reaction mechanism for photolytic dechlorination of PCBs in aquatic system.

• The Journal of Advanced Prosthodontics
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• 제12권5호
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• pp.259-264
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• 2020

PURPOSE. The aim of this study was to investigate and compare the color stability of provisional restorative materials fabricated by 3D printing, dental milling, and conventional materials. MATERIALS AND METHODS. For the experimental groups, two commercially available 3D-printing provisional resins (E-Dent 100; EnvisionTEC GmbH, Germany & VeroGlaze™; Stratasys^®, USA), two dental milling blocks (PMMA Disk; Yamahachi Dental Co., Japan & Telio^®CAD; Ivoclar Vivadent AG, Liechtenstein), and two conventional materials (Alike™; GC Co., Japan & Luxatemp automix plus; DMG, Germany) were used. The water sorption and solubility test were (n=10, respectively) carried out according to ISO4049:2000 (International Standards Organization, Geneva, Switzerland). For the color stability test (n=10), coffee and black tea were used as staining solutions, and the specimens were stored for 12 weeks. Data were analyzed by one-way ANOVA and Tukey's HSD using SPSS version 22.0 (SPSS Inc. Chicago, IL, USA) (P<.05). RESULTS. Alike and Veroglaze showed the highest values and Luxatemp showed the lowest water sorption. In the color stability test, the ΔE of conventional materials varied depending on the staining solution. PMMA milling blocks showed a relatively low ΔE up to 4 weeks, and then significantly increased after 8 weeks (P<.05). 3D-printed materials exhibited a high ΔE or a significant increase over time (P<.05). CONCLUSION. The degree of discoloration increased with time, and a visually perceptible color difference value (ΔE) was shown regardless of the materials and solutions. PMMA milled and 3D-printed materials showed more rapid change in discoloration after 8 weeks.

• 의학교육논단
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• 제20권2호
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• pp.112-117
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• 2018

Attending the operation room is an essential part of surgical clerkships. Syncope or presyncopal attacks in the operation room may negatively affect students' learning and career development. This study set out to identify the prevalence of syncope and presyncopal attacks in the operation room during medical students' surgical clerkships. Data from 420 medical students (303 men and 117 women) in their 3rd year of clerkship were collected between 2014 and 2017. An anonymous questionnaire was distributed to assess the prevalence and degree of syncope and presyncopal symptoms. A total of 27% of the respondents had experienced syncope or presyncopal symptoms, 49.6% of the female students and 18.8% of the male students (p<0.001). Fifty students (43.5%) had been attending as observers at the time of the syncopal attack, while 65 students (56.5%) had been participating as assistants. Thirty-four students (29.6%) had recently eaten at the time of the syncopal attack, while 81 students (70.4%) had not recently eaten. Prodromal symptoms included the urge to sit down (21.2%), sweating (19.3%), nausea (16.9%), a feeling of warmth (13.3%), darkened vision (12.6%), yawning (11.7%), palpitation (11.0%), ear fullness (10.2%), black spots in one's vision (7.6%), and hyperventilation (7.1%). This study showed the prevalence of syncope and presyncopal symptoms in the operation room during surgical clerkships. For students' safety and effective clerkship learning, thorough proactive education on syncopal attacks is required.

• 한국식품조리과학회지
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• 제28권6호
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• pp.789-796
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• 2012

This study attempted to investigate the characteristics of Superjami, which had a high C3G (cyandin-3-glucoside) content by comparing it with common rice (Ilpum) and black rice (Heougjinju, Suwon 415) for their components and physio-chemical characteristics. There were no significant differences in the water content, however there were significant differences in crude protein and crude fat in the order of Ilpum < Superjami < Heougjinju. As for the morphological characteristics of grains, it had been learned that Superjami was heavier and longer than the common rice, moreover Superjami had bigger seeds. As for the hardness of grains, the longer the time of steeping, the more decreased their hardness was at large. In the case of color, they showed significant differences in all the L, a, and b values of grains and flours. As a result of the experiment of pigment elution after steeping of the rice flours at $20^{\circ}C$ and $40^{\circ}C$, the longer the time steeping, the more increased the pigment elution became. The values are bigger with Heougjinju and Superjami than with Ilpum. As for the elution pH after rice steeping, the longer the time of steeping, the lower pH all the assays tended to have. As a result of the analysis of the total polyphenol contents of Ilpum, Heougjinju, and Superjami, it had turned out that the total polyphenol contents of Heougjinju and Superjami are 1.2 times as high as Ilpum, a common rice, and that Superjami is significantly higher than Heougjinju. As a result of the experiment of DPPH radical scavenging ability, there are significant differences among the assays in the order of Superjami > Heougjinju > Ilpum. Futher, it has turned out that Superjami has a higher DPPH radical scavenging ability than Heougjinju. Consequently, it can be stated that Superjami has a strong anti-oxidative ability. Thus, we should more precisely grasp the cooking characteristics of Superjami, which is in the state of brown rice, via comparing it with a common brown rice, and also provide opportunities to apply Superjamii to more foods by studying its starch characteristics in addition to its grain and flour properties.

• Journal of Plant Biology
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• 제1권1호
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• pp.11-20
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• 1958

I. Assumption: Mo-kam-ju, Koelreuteria paniculata is a woody plant mainly cistributed over Northern China. Its sporadic growth along the beaches of Korea and Japan is assumed to have been sowed by the seeds transported adrift on the current across the ocean. II. Use and Growth of the Plant: In China, this plant has been cultivated from early times mainly at temples, it seeds being used as rosaries, its flowers for yellow dyes and medicine for the eyes, and its leaves for black dyes. In Korea and Japan, these plants have been cultivated at temples and used as the material for rosaries. No natural growth of these plants was reported until 1919. III. Discoveries: In this domestic area, Dr. Chung Tae Hyun discovered the plant on the beach between Cho-Do and Chang-san-kot, Hwang-Hae Prov. in 1920. The reporter discovered them on the beach at Buk-Ni, Duk-jok-Do in 1948, at An-Hung in 1956 and on the beach at An-min-Do in 1957. In the Japan area, it was discovered for the first time twenty years ago, mainly along the coast line of the Japan Sea and some along the eastern coast line, at Subo, Yamaguchi Prefecture facing the Pacific Ocean. IV. Study and Experiment: A. Seed The seed coat is thick, non-permeable and floatable. A number of seeds were immersed in artificial sea water and fresh water separately. The seeds remained there for a hundred and forty-five (145) days from April 6, 1957 to August 29, 57. Thirty one seeds out of the fifty immersed in salt water and twenty seeds out of the fifty immersed in fresh water remained on the surface of the water, proving them to be non-permeable to both sea and fresh water. Of course, these had retained their germinating capabilities. Five (5) seeds out of twenty from the fresh water and six (6) out of thirty-one from the sea water were successfully germinated after a hole had been drilled in the seed coat and they had been planted. Thus their floating capability, non-permeability and germinating capability after a possible 145 day trip on the flowing currents has been proved satisfactory according to the assumption made above. B. Current As shown in the Data 2 and 3, the sea current initiated in the Pohai Sea flows westward down along the coast line of Korea reaching the southern part during the autumn and winter seasons. This fact also is in favor of the reporter's assumption. V. Discussion and Conclusion: The reporter concludes that, as discussed above, Koelreuteria paniculata which originates in Northern China is transported adrift on the flowing sea current to our western coast line, and also the coast lines of Shantung and Kuangtung of China and it is germinated on the sandy beaches forming new plants. Thus, the seeds drifted down on the southern beach of Korea and have been transported to the Japanese coast, adrift on the Tae-Ma current. Upon fruition, the seeds of the plants which settle on the coasts of western Korea and Japan will migrate to new places. It can be, however, assumed that while the thickness and nonpermeability of the coat enables the long travel in the water, this also can compose a difficulty in germination, consequently in developing a new distribution of this species.

• 한국작물학회지
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• 제2권
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• pp.30-37
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• 1964

대두품종의 파종기별 수량과 제특성간의 관계, 그리고 파종기별 수량의 품종간의 차이를 알고자 1962년과 1963년의 각 파종기에 대하여 실험한 바 그 결과를 요약하면 다음과 같다. 1. 파종기별 수량과 몇가지 생태적 특성과의 상관관계는 Table 1과 같이 대체로 개화일수와 생육일수는 극만파(7월파종)의 경우를 제외하고 수량과 정의 상관을 보이고 그 정도는 조기파종구에 있어서 더욱 높았다. 그리고 개화기간은 수량과 부의 상관의 경향이 보이고 결실일수는 년차나 파종기에 따라서 그 관계가 명료하지 아니 하였다. 2. 파종기별 수량과 몇가지 형태적 특성과의 상관관계는 Table 2와 같이 대체로 분기수 경직경 1주중량, 1주맥수 그리고 1주입수는 수량과 어느 파종기에 있어서도 정의 상관관계를 보이고 경장과 수량 그리고 100 입중과 수량간에는 년차 파종기에 따라서 그 관계가 명료하지 아니하였다. 따라서 수량에 영향하는 특성은 개화일수, 생육일수의 두 생태적 특성과 함께 분기수, 경직경, 1주중량, 1주맥수 그리고 1주입수의 제형태적 특성이라고 할 수 있겠다. 3. 품종수량순위가 파종기에 따라 변동하는 경향을 보면 Table 3과 같이 대체로 공시품종중 울산, 상두, 장단백자, 익산, 함안, 반청두, 안전대입은 어느 파종기에 있엇도 높은 수량을 나타내고 이들은 성숙군이 IV, V, VI에 해당하는 중, 만생종으로 우리나라 중요재래품종들이며 극조생종이나 극만생품종은 수량은 떨어지나 극조생 또는 조생종중에서도 Black Hawk, 충북백 등은 만파의 우연에, 만생종인 동산006 등은 조파의 경우에 높은 수량을 보이는 품종들이었다. 4. 품종별 수량이 파종기에 따라서 변동하는 경향을 보면 Table 4와 같이 대체로 조생종에 있어서는 파종기 연장에 따라 수량 감소의 정도가 낮고 도리어 조파보다 만파의 경우에 좋은 성적을 나타 내었으나 중생종, 만생종일수록 파종기 연장에 의한 수량 감소의 정도가 높았다. 옥면과 같은 극만생종 품종은 조반의 경우라도 상해 등으로 본실험지의 기후조건 하에서는 경제적 재배가 곤란하다고 믿는다. 따라서 조생종에 있어서는 5월 이후의 만파의 경우에, 중, 만생종에 있어서는 4월보다 도리어 5월 파종의 경우에 좋은 성적을 나타내는 경향이 있으나 품종별 파종 최적기 등의 결정문제는 앞으로 해결되어야 할 한 과제가 될 수 있을 것이라 하겠다.