• 제목/요약/키워드: Co-cure

검색결과 154건 처리시간 0.022초

기후변화에 따른 유역의 수문요소 및 수자원 영향평가 (Impact Assessment of Climate Change on Hydrologic Components and Water Resources in Watershed)

  • 권병식;김형수;서병하;김남원
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2005년도 학술발표회 논문집
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    • pp.143-148
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    • 2005
  • The main purpose of this study is to suggest and evaluate an operational method for assessing the potential impact of climate change on hydrologic components and water resources of regional scale river basins. The method, which uses large scale climate change information provided by a state of the art general circulation model(GCM) comprises a statistical downscaling approach and a spatially distributed hydrological model applied to a river basin located in Korea. First, we construct global climate change scenarios using the YONU GCM control run and transient experiments, then transform the YONU GCM grid-box predictions with coarse resolution of climate change into the site-specific values by statistical downscaling techniques. The values are used to modify the parameters of the stochastic weather generator model for the simulation of the site-specific daily weather time series. The weather series fed into a semi-distributed hydrological model called SLURP to simulate the streamflows associated with other water resources for the condition of $2CO_2$. This approach is applied to the Yongdam dam basin in southern part of Korea. The results show that under the condition of $2CO_2$, about $7.6\% of annual mean streamflow is reduced when it is compared with the observed one. And while Seasonal streamflows in the winter and autumn are increased, a streamflow in the summer is decreased. However, the seasonality of the simulated series is similar to the observed pattern and the analysis of the duration cure shows the mean of averaged low flow is increased while the averaged wet and normal flow are decreased for the climate change.

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전부도재관용 레진시멘트의 생체적합성에 관한 연구 (A STUDY ON BlOCOMPATABILITY OF RESIN CEMENTS FOR ALL-CERAMIC CROWN)

  • 김광준;김성훈;진태호
    • 대한치과보철학회지
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    • 제41권2호
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    • pp.111-127
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    • 2003
  • Statement of problem : Resin cements were used widely on all ceramic crowns, but the influence of resin cements on biocells was not understood clearly. Purpose : This study was investigated to evaluate the biocompatibility of resin cements for all-ceramic crowns. Material and Method : The resin cements used in this study were Panavia F (Kuraray Co., Ltd. Japan), Variolink II (Vivadent Ets., Schann / Liechtenstein), and Bistite II (Bistite dual cure resin cement-clear Tokuyama Soda Co. Japan). The viability of normal human oral keratocytes, gingival fibroblast, and gingival fibroblast immortalized by Human Papilloma virus 16 was measured in vitro for evaluation of cytotoxicity on resin cements, and the response of pulp tissue was analyzed and evaluated with light microscope after application of cements at cutting edge of incisors. Results : The normal human oral keratocytes was the most sensitive to toxicity of resin cement, and toxicity of cements was higher in Bistite II than in Variolink II. The cell viability of immortalized gingival fibroblast did not affected by type of cement and cultivation period, but there was a tendency that cytotoxicity in Bistite II was higher than in Variolink II. The cell viability of gingival fibroblast was similar to that of immortalized gingival fibroblast regardless of cement type, but Bistite II showed more toxic than others after 5 days cultivation. The responses of pulp tissue according to cement type were similar after 2 days cultivation, but revealed high toxicity in Bistite II after 10 days cultivation. Conclusion : Variolink II was more biocompatible than any other resin cements used in this study.

Research Trends of Coronavirus: Bibliometric Analysis from 1989-2019

  • Singh, Shiv;Kataria, Sanjay;Dey, Tulika
    • International Journal of Knowledge Content Development & Technology
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    • 제11권4호
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    • pp.101-111
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    • 2021
  • The world is going through the most unprecedented time with the outbreak of novel Coronavirus disease (COVID-19), which has become a threat to millions. A Coronavirus is a group of viruses that cause a variety of diseases in mammals and birds leading to a range of illnesses in humans including common cold and more severe forms like severe acute respiratory syndrome Coronavirus (SARS-CoV), Middle East respiratory syndrome Coronavirus (MERS-CoV) and COVID-19, which are life-threatening. The virus gets its name from its shape which takes the form of a crown with protrusions around it. In December 2019, a pneumonia outbreak was reported in the Wuhan City of China, which was later traced to a novel strain of Coronavirus and termed as Novel COVID-19. It typically causes flu-like symptoms including fever, cough and shortness of breath and is transmitted through human-to-human and there is no cure for it till now. Thus, this bibliometric study has been carried out to analyze the research progress in Coronavirus and literature published during a period of 30 years (1989-2019). Data for the study were fetched from Web of Science(WoS) multidisciplinary database and the publication trends in terms of total articles, productive countries, institutions, journals, productive authors, most cited articles and authors, etc have been analyzed. In total, 4917 articles were retrieved; these were from 711 sources and were contributed by 14442 authors. The collaboration index was 3.11, which clearly indicates that there has been a lot of collaboration in this field. The most preferred journal for the study period was "Journal of Virology" and the maximum contribution has been from the University of Hong Kong.

중학교 교과과정에 따른 보건교육 내용 분석 연구 (A study on health education content analysis in middle school curriculum)

  • 유재복
    • 한국학교보건학회지
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    • 제3권1호
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    • pp.59-72
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    • 1990
  • The study reserches the related contents of the health education in the existing gymnastics and the domestics textbook, catches learning-Ulaching contents by the health-control function and compares the contents with the health-education curriculum of the Texas State in America. This study is questioned and reserched the general features of the teachers who is change in the health education, their attitudes about the teaching of it, and the recognition degree about their health education. The results above is like the following. 1. Learning-teaching contents by the health-control function. The domestics and gymnastics which contains the health education contents, is not discripted continually and at the same time is short of the contents in the health-control function according to the students' individual domains. Also the recent serious problems, (that is, Smoking, Drinking and Medical poisoning, Emotion, and Psychic domains) were no mentioned. 1) In gymnastics textbook, the physical domains are mentioned 8, 9 in juinor, and senior class, the affective, psychic domains only senior class and the social domains only 1 grade except junior and senior class. Growth-development function is concentratedly stated only 1 grade in physical domains and there is no stated in. The social domains are referred a little in senior class. In cure-recovery functions, the physical domains is being taught in 2, and 3 grade, but not 1 grade. Specially, the social domains are being taught in all grade, but, the affective domains are not at all 2) In the subject of domestics, the physical domains of the daily life functions are taught in all the years, but the emotional, mental domains are taught a little in 1 and 2 grades. The growth-development functions are being taught about the nutrition-health, in the physical parts of all graries, and the emotional-mental, social domains are being taught some in 7 and 8 grade except 3 grade, he cure-recovery functions ere taught in only 1 grade, the contents of rehabilitative functions are not being taught like gymnastics. 2. The general characteristics of the health-education teachers and the health-education. In the calss field, the average age of gymnastics-teachers is from 35 to 40 years old, and it of domestics teachers is from 24 to 29 years old. 1) In the class-hours a week, the gymnastics teachers take lessons 3 hours (75.6%) and the domestics teachers 4 hours (65.6%). In "the health-lessons hours alloted"in a semister, 3 or 4 hours is 38.7% and no hours is 18.0% in gymnastics teachers. On the other hand, there is no hours to teach the health-education in domestics teachers. About the opinion: the health subject must be taught as a independent subject, 42.9% of the gymnastics teachers agreed and 45.3 % of the domestics teachers did. 2) The factors which have an influence upon the health-teachers #. In age, the class lesson hours of a week(r= .0014), the confident manner about the lessons(r= .0485) and the necessity of the lessons (r= .0316) are closely related one another. #. In sexes, the lesson hours a class(r= .0000), the alloted hours of health lesson a semister(r= .0000) the confident manner about the class(r= .0001). the quantity of lesson(r= .0001): and, the teacher's belief(r= .0264) are co-related one another. #. In subject in change. the class hours a week(r= .0000), the alloted hours of health-lesson a semister(r= .0000) the quantity of the lesson(r= .0114) are co-related each other. #. In majority, the class lesson hours a week(r= .0000) the alloted hours of health lesson a semister(r= .0000) the quantity of the lesson are co-related each other. The quantity of lesson and the confidence about the lesson (r= .3223) and the quantity of lesson and the interest of lesson (r= .2450) are co-related each other.

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접착용액을 이용한 케나프섬유 처리 유·무에 따른 케나프/천연고무 복합재료의 경화특성, 경도, 인장탄성률 및 마모에 미치는 케나프섬유의 함량 및 길이의 영향 (Effect of Kenaf Fiber Content and Length on the Cure Characteristic, Hardness, Tensile Modulus, and Abrasion of Kenaf/Natural Rubber Composites in the Presence and Absence of Kenaf Fiber Treatment with Adhesive Solution)

  • 조이석;조동환
    • 접착 및 계면
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    • 제19권2호
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    • pp.60-67
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    • 2018
  • 본 연구에서는 친환경 천연섬유인 케나프의 표면을 Chemlok 402를 함유하고 있는 접착용액으로 전처리하였을 경우, 케나프/천연고무 복합재료의 경화거동, 경도, 인장특성 그리고 마모특성에 미치는 섬유 표면처리 유 무, 섬유함량 및 섬유길이의 영향을 조사하였다. 복합재료를 구성하는 케나프섬유 함량은 평균 케나프섬유의 길이가 약 2 mm로 일정한 상태에서 각각 0, 5, 10, 15, 20 phr로 달리하였다. 또한 섬유함량이 5 phr로 고정된 상태에서 평균 섬유길이는 각각 2 mm, 35 mm, 70 mm로 달리하여 각 특성을 비교하였다. 천연고무 복합재료의 경화거동을 나타내는 Tmax 값과 tc90 값, Shore A 경도, 인장탄성률 그리고 마모저항성은 케나프섬유 함량과 길이에 크게 의존하였다. 이러한 특성들은 케나프섬유의 표면을 접착용액으로 전처리한 경우가 처리하지 않은 경우보다 더 우수한 특성을 나타냈다. 이러한 현상은 전처리된 케나프섬유와 고무매트릭스 사이의 계면접착 상태가 개선되었기 때문이다. 본 연구결과는 천연섬유강화 복합재료의 물성을 향상시키기 위해 접착용액의 적절한 사용이 가능하다는 것을 제시하여 준다.

레진시멘트의 중합방법이 포스트의 결합강도와 접착계면에 미치는 영향 (EFFECT OF CURING METHODS OF RESIN CEMENTS ON BOND STRENGTH AND ADHESIVE INTERFACE OF POST)

  • 김문홍;김혜정;조영곤
    • Restorative Dentistry and Endodontics
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    • 제34권2호
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    • pp.103-112
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    • 2009
  • 본 연구에서는 2종의 이원중합 레진시멘트 (RelyX ARC와 Variolink II)를 이용하여 접착제와 레진시멘트의 중합방법 (자가중합과 광중합)이 섬유포스트와 근관 상아질의 결합강도와 접착계면에 미치는 영향을 상호 비교하기 위하여 시행하였다. 단근관을 갖는 발거된 32개의 하악 소구치에 근관을 충전한 후, FRC Postec system의 Reamer로 9 mm 깊이의 포스트 공간을 형성하였다. 레진시멘트의 종류와 중합방법에 따라 4개의 군 (R-SC군, R-LC군, V-SC군, V-LC군)으로 분류하였다. 포스트 공간에 각 군의 접착제를 도포한 후 레진시멘트를 주입하고, No. 3 FRC Postec 포스트를 위치시켜 자가중합 또는 광중합시켰다. 각 군의 치근을 실온의 증류수에 24시간동안 보관한 다음, 저속의 diamond wheel saw를 이용하여 치관부에서 치근단부를 향해 1.5 mm두께로 연속적으로 횡절단하여 1개의 치근에서 3개의 절편을 얻었다. 각 군의 절편 (31개)은 만능시험기에서 push-out 검사를 시행하였고, 각 군의 강도 값은 반복측정 two-way ANOVA와 one-way ANOVA를 이용하여 비교 분석하였다. 각 군의 절편 (3개)은 주사전자현미경하에서 섬유포스트, 레진시멘트 및 치근 상아질 간의 계면을 관찰, 비교하였다. 본 연구의 결과 전 부식 레진시멘트를 이용하여 섬유포스트를 포스트 공간에 합착할 경우, 접착제와 레진시멘트의 중합방법은 근관 상아질의 결합강도에 영향을 주었으며, 광중합보다 자가중합 방법 이 우수한 결합강도와 계면을 나타내었다.

1급 와동에서 상아질과 복합레진의 결합강도에 대한 중합방법의 효과 (THE EFFECT OF DIFFERENT CURING MODES ON COMPOSITE RESIN/DENTIN BOND STRENGTH IN CLASS ICAVITIES)

  • 백신영;조영곤;송병춘
    • Restorative Dentistry and Endodontics
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    • 제33권5호
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    • pp.428-434
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    • 2008
  • 본 연구는 1급 복합레진 수복물에서 할로겐 광조사기를 이용한 4가지 중합방법이 상아질의 결합강도에 미치는 효과를 알아보기 위하여 시행하였다. 발거된 상 하악 대구치 20개의 교합면측 법랑질을 Diamond Wheel Saw를 이용하여 제거한 후 1급 와동을 형성하였다. 중합방법에 따라 파동지연 중합방법 (PD) 군, 연성 중합방법 (SS) 군, 파동 중합방법 (PC) 군, 지속 중합방법 (CC) 군의 4개 군으로 분류하고, Z250 복합레진을 각 군의 와동에 충전한 후 광조사하였다. 각 군의 시편을 주수하에 접착계면의 단면적이 $1mm^2$가 되도록 절단하여 막대모양의 시편을 제작하였고, 각 군당 20개의 시편을 사용하여 미세인장 결합강도를 측정하여 다음과 같은 결과를 얻었다. 1. PD 군은 PC 군과 CC 군보다 통계학적으로 더 높은 미세인장 결합강도를 나타내었다. 2. SS군의 미세인장 결합강도는 PC 군과 CC 군보다 높게 나타났으나, 통계학적으로 유의한 차이를 나타내지 않았다. 결론적으로, 1급 복합레진 수복물을 중합할 때 파동지연 중합방법과 연성 중합방법을 사용하여 중합속도를 조절함으로써 상아질과 복합레진의 결합강도를 개선할 수 있을 것으로 사료된다.

가족발생(家族發生) 양측성(兩側性) 성인형(成人型) 다낭종신(多囊腫腎) 3례(例)의 초음파진단(超音波診斷) - 보험가입자(保險加入者)를 대상(對象)으로 - (A Ultrasonic Diagnosis of Family Incidence Bilateral Adult Type Polycystic Kidney: Three Cases)

  • 문수형;한혜진;김강석
    • 보험의학회지
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    • 제2권1호
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    • pp.218-232
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    • 1985
  • Congenital hereditary disease is in devided into Infantile type and Adult type, Adult type is hidden for many years and keeps normal renal function till middle age. Cyst is stimultaneously made in both sides and becomes lowered in renal function in 30's to 40's. Infantile type is generally born with the big kidneys, renal failure, undergrowth of intrahepatic bile duct. Both infantile and childhood type have ureteral dilatation and portal hypertension In infantile type, it is mostly developed into renal failure, but generally faces death as a result of hepatic disease. The reason of death is that an abnormal condition of recessive autosome affects the liver and kidneys. While the incidence of infantile type is rare as $0.017{\sim}0.07%$ and it is autosomal recessive heredity, Adult type can rarely exist in infantile period. Though it exists in middle period, 50% of patients can live for 2-4 years after the first symptom incidence and 25% can less than 2 years. It is hard to cure completely in medicine and surgery. Three difficulties in familial incidence are comparative decrease of the donor who have no affection on renal transplantation. For another consideration it is to show the family history for several generations. We, the Med. Dept. of Dae Han Kyouk Life Insurance Co. Ltd., used the ultrasonic apparatus in diagnosing the one case of adult type bilateral polycystic kidney and then doubted the family history. As a result of inspecting the family we experienced bilateral polycystic kidney from 3 persons out of 4 who can be inspected. The results are as follows: 1) We could confirm the polycystic kidney from 3 persons out of 4(75%). 2) Then when they came for check up, chief complaint was the pain in all 3 cases(100%). 3) Accompanying disease was hypertension in 2 cases(67%). 4) In early disease incidence, we couldn't observe the specific change in pathological opinion. 5) All 3 cases are not accompanied with cystic lesion in liver, spleen, pancreas.

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SBR/Organoclay Nanocomposites for the Application on Tire Tread Compounds

  • Kim, Wook-Soo;Lee, Dong-Hyun;Kim, Il-Jin;Son, Min-Jin;Kim, Won-Ho;Cho, Seong-Gyu
    • Macromolecular Research
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    • 제17권10호
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    • pp.776-784
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    • 2009
  • N,N-dimethyldodecylamine (tertiary amine)-modified MMT (DDA-MMT) was prepared as an organically modified layered silicate (OLS), after which styrene-butadiene rubber (SBR) nanocomposites reinforced with the OLS were manufactured via the latex method. The layer distance of the OLS and the morphology of the nanocomposites were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). By increasing the amount of N,N-dimethyldodecylamine (DDA) up to 2.5 g, the maximum values of torque, tensile strength and wear resistance of the SBR nanocomposites were increased due to the increased dispersion of the silicate layers in the rubber matrix and the increased crosslinking of the SBR nanocomposites by DDA itself. When SBR nanocomposites were manufactured by using the ternary filler system (carbon black/silica/OLS) to improve their dynamic properties as a tire tread compound, the tan $\delta$(at $0^{\circ}C$ and $60^{\circ}C$) property of the compounds was improved by using metal stearates instead of stearic acid. The mechanical properties and wear resistance were increased by direct substitution of calcium stearate for stearic acid because the filler-rubber interaction was increased by the strong ionic effect between the calcium cation and silicates with anionic surface. However, as the amount of calcium stearate was further increased above 0.5 phr, the mechanical properties and wear resistance were degraded due to the lubrication effect of the excessive amount of calcium stearate. Consequently, the SBR/organoclay nanocomposites that used carbon black, silica, and organoclay as their ternary filler system showed excellent dynamic properties, mechanical properties and wear resistance as a tire tread compound for passenger cars when 0.5 phr of calcium stearate was substituted for the conventionally used stearic acid.

가시광선 중합기의 조사강도 감소에 대한 조사시간 증가의 보상효과 (COMPENSATION EFFECT OF EXPOSURE TIME INCREASE TO DECREASED LIGHT INTENSITY OF VISIBLE-LIGHT CURING UNIT)

  • 윤태원;이창섭;이상호
    • 대한소아치과학회지
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    • 제24권1호
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    • pp.325-336
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    • 1997
  • The purpose of this study was to evaluate the compensation effect of exposure duration increase to decreased light intensity of visible-light curing unit. The specimen with 2mm thickness was made of Restorative $Z-100^{TM}$ (A2 shade, 3M Dental Products, U.S.A.) and cured with $Optilux^{TM}$ (Demetron Research Co. U.S.A.). The light intensity was controlled to 420 $mW/cm^2$, 540 $mW/cm^2$, 630 $mW/cm^2$ and curing time, also, controlled to 40, 60, 80 seconds. Cured specimen was stored in a light-proof container for 24 hours to post-irradation was completed. Microhardness of top and bottom surface of specimen were measured to evaluate the depth of cure. The obtained results were as follows: 1. The microhardness of top and bottom surface of the composite resin specimen was increased significantly as light intensity and exposure time was increased (P<0.01). 2. Light intensity was more correlated with bottom microhardness(${\gamma}{\geq}$0.438) than top microhardness(${\gamma}{\geq}$0.213), and exposure time was more correlated with top microhardness (${\gamma}{\geq}$0.424) than bottom microhardness(${\gamma}{\geq}$0.335). 3. The regressive equation was obtained in this study as follows : $H=0.07{\times}D+0.012{\times}I+76$ (H : Microhardness(KHN), D : Exposure time, I : Light intensity)

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