• 대한소아치과학회지
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• 제27권1호
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• pp.85-89
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• 2000

치면열구 전색재가 교합면 열구우식의 억제에 예방효과를 보임은 이미 잘 알려져 있다. 최근에 들어서는 치면열구 전색재가 불소를 유리하도록 성분적인 첨가를 하려는 시도가 있었고, 여러 제품이 현재 이러한 특징을 가지고 시판되고 있다. 그러나, 불소를 유리하는 장점은 가졌으나, 물성의 저하가 초래되지는 않았을지 에 대한 의문을 가질 수 있다. 본 연구에서는 일반 레진계 전색재, 불소유리 전색재, GI계 전색재 등 4종의 치면열구 전색재의 유지력을 전단결합강도를 측정으로 비교 분석하여 다음과 같은 결론을 얻었다. 1. 레진계 전색재인 Helioseal과 Teethmate-A가 불소유리 레진계 전색재인 Teethmate-F에 비해 전단결합강도가 약간 크게 나타나기는 하였으나, 유의한 차는 없었다(p>0.05). 2. GI계 전색재인 Fuji III의 전단결합강도는 레진계 전색재에 비해 상당히 낮았다(p<0.05). 3. 위 실험결과에서처럼 레진계 전색재에서 우식예방효과를 증대시킬 목적으로 불소를 포함시켰을 때, 전색재의 유지력에 큰 영향을 미치지는 않는 것으로 생각되었다.

• 융복합기술연구소 논문집
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• 제5권1호
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• pp.13-17
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• 2015

In wafer level molding progress, the thermal releasing failure phenomenon is shown up as the important problem. This phenomenon can cause the problem including the warpage, crack of the molded wafer. The thermal releasing failure is due to the insufficiency of adhesion strength degradation of the molding tape. To solve this problem, we studied experimental method increasing the release property of the molding tape through the plasma surface treatment on the wafer substrate. In this research, the vacuum plasma treatment system is used for release property improvement of the molding tape and controls the operating condition of the hydrophilic($O_2$, 100kW, 10min) and hydrophobic($C_2F_6$, 200kW, 10min). In order to perform the peeling test for measuring the releasing force precisely, we remodel the micro scale material property evaluation system developed by Korea institute of industrial technology. In case of hydrophilic surface treatment on the wafer substrate, we can figure out the releasing property of molding tape increase. In order to grasp the effect that it reaches to the release property increase when repeating the hydrophilic treatment, we make an experiment with twice treatment and get the result to increase about 12%. We find out the hydrophilic surface treatment method using plasma can improve releasing property of molding tape in the wafer level molding process.

• 대한환경공학회지
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• 제29권12호
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• pp.1345-1352
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• 2007

퇴적물로부터 용출되는 영양염류가 인공호수인 남양호의 수질에 미치는 영향을 예측하기 위하여, 실험실에서 퇴적물의 조건을 호기 및 혐기조건으로 설정한 후 영양염류의 용출속도를 측정하였다. 퇴적물로부터 유기물과 질소의 용출은 일어나지 않는 것으로 판단된다. 인산염 인과 총인의 경우 수체 내 산소조건에 따라 용출 양상이 달랐는데, 혐기조건에서는 인이 용출되지 않은 반면, 호기 조건에서는 많은 양의 인이 용출되었다. 실험 결과를 기초로 호기조건에서 인의 용출 속도를 계산한 결과 인산염 인의 경우 $1.01\sim2.48$ mg-P/$m^2$/day이며, 총인의 경우는 $2.14\sim3.54$ mg-P/$m^2$/day로 나타났다. 상류에서 채집한 퇴적물에서 인의 용출 속도가 가장 빨랐는데, 이는 유입수에 쉽게 분해 가능한 유기물이 다량 포함되어 있기 때문으로 사료된다. 남양호의 경우 가장 깊은 하류의 수심이 $7\sim14$ m로 성층화가 이루어지지 않기 때문에, 대부분의 퇴적물 환경이 호기성 상태이다. 본 연구의 결과 남양호 퇴적물 중에 포함된 인이 호기성 상태에서 다량 용출되고 있기 때문에 인의 용출에 의한 수질 오염 문제에 대한 적절한 대책이 필요할 것으로 판단된다.

• 구강회복응용과학지
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• 제21권1호
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• pp.25-32
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• 2005

The purpose of this study was to examine an effect of fluoride recharging on fluoride release and surface change of fluoride-releasing restorative materials. Six commercially available fluoride releasing restorative materials (Fuji II LC Improved: FL, Compoglass F: CF, Dyract AP: DA, F2000: FT, Gradia Direct: GD, and Tetric Ceram: TC) were selected as experimental materials. Disk specimens were fabricated with split teflon mold to the final dimensions of 15 mm in diameter and 1 mm in thickness. Ten samples of each material were fabricated and stored in deionized water at $37^{\circ}C{\pm}1^{\circ}C$ for 3 months. Before fluoride recharging, all specimens were polished sequentially from #800 to #2000 emery papers. Fluoride recharging was done at 5-day interval using 2.0% NaF gel. The release of fluoride into the storage water was monitored using a fluoride ion electrode. Data were analyzed by one-way ANOVA and Tukey's multiple range test. The results obtained were summarized as follows; 1. Fluoride recharge capability were FL > CF > DA and TC group after 12 times exposure to 2.0% NaF gel (P<0.05). 2. All the experimental materials, except for FT group, showed the increase of fluoride release and surface roughness. 3. Fluoride-releasing rates returned to base line within 3 days.

• 한국환경농학회지
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• 제11권2호
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• pp.155-162
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• 1992

수용해도가 2.53ppm인 KC-6620을 수중용출기간이 20일 정도인 입제로 제제하기 위하여 원제에 대한 용출지연효과가 가장 큰 다공성 증량제를 선발하고, PEG를 부제로 첨가한 흡착식 입제를 제제하여 실내에서 수중용출속도를 측정하였다. 1. 다공성 증량제중 KC-6620에 대하여 용출지연효과를 나타낸 것은 bentonite 소결공립이었으나 수중에 침적 20일후의 용출율이 매우 낮았다. 2. Bentonite에 pyrophyllite를 혼합하고 조립한 다음 소결시킴으로써 흡유가가 증가하였으며, 이 공립으로 제제한 KC-6620 입제의 수중용출속도도 증가하였다 BP60 입제의 경우 침적 20일후에 85% 이상의 용출율을 보여 시험한 입제중 단기용출지연제제로 가장 적합하였다. 3. BP입제는 PEG를 부제로 첨가하여 용출속도를 증가시킬 수 있었으며, PEG의 첨가비가 공립의 흡유가까지 증가할수록 용출속도도 증가하였다. 4. BP40 입제는 입제중의 유효성분함량이 높을수록 수중용출속도가 느려져서 제제농도가 용출속도를 좌우하는 가장 큰 요인이었다.

• Industrial Engineering and Management Systems
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• 제2권1호
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• pp.9-27
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• 2003

In a wafer fabrication factory, the completion time of an order is affected by many factors related to the specifics of the order and the status of the system, so is difficult to predict precisely. The level of influence of each factor on the order completion time may also depend on the production system characteristics, such as the rules for releasing and dispatching. This paper presents a method to identify those factors that significantly impact upon the order completion time under various combinations of scheduling rules. Computer simulations and statistical analyses were used to develop effective due date assignment models for improving the due date related performances. The first step of this research was to select the releasing and dispatching rules from those that were cited so frequently in related wafer fabrication factory researches. Simulation and statistical analyses were combined to identify the critical factors for predicting order completion time under various combinations of scheduling rules. In each combination of scheduling rules, two efficient due date assignment models were established by using the regression method for accurately predicting the order due date. Two due date assignment models, called the significant factor prediction model (SFM) and the key factor prediction model (KFM), are proposed to empirically compare the due date assignment rules widely used in practice. The simulation results indicate that SFM and KFM are superior to the other due date assignment rules. The releasing rule, dispatching rule and due date assignment rule have significant impacts on the due date related performances, with larger improvements coming from due date assignment and dispatching rules than from releasing rules.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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• pp.277-278
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• 2010

현재 사용되는 콘크리트의 이형제들은 대부분 소수성 물질로써 다량의 VOC를 함유하고 있을 뿐만 아니라, 콘크리트 타설 중에 포함된 기포가 형틀 표면에 부착되어 경화 후 핀홀, 펀칭홀 등을 유발시킨다. 본 연구에서는 이러한 이형제의 기본 특성 개선과 함께 마감공정을 단축시킬 수 있는 부가형 이 형제를 개발하는데 목적을 두고 있다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권5호
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• pp.2185-2190
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• 2014

Chemotherapy has significantly improved the prognosis of cancer patients with various malignancies. However, female patients, especially those whoich are premenopausal, suffer from significant chemotherapy induced ovarian function impairment, which decreases their quality of life. Many new techniques for ovarian preservation have been established in recent years. Although the use of gonadotrophin releasing hormone analogues (GnRHa) for this purpose is not a new concept, its effectiveness in protection of ovarian function is still debatable. This article deals with studies and metaanalyses which have been undertaken in the past, demonstrating the impact of GnRHa in ovarian function preservation, and whether their use can be implemented in routine practice.

• Clinical and Experimental Pediatrics
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• 제49권7호
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• pp.718-725
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• 2006

The pubertal activation of gonadotrophin releasing hormone(GnRH) requires coordinated changes in excitatory or inhibitory amino acids, growth factors, and a group of transcriptional regulators. The age of onset of puberty is progressing to younger age. Factors affecting early puberty include genetic traits, nutrition(body fat) and exposure to endocrine disrupting chemicals. In rapidly progressing central precocious puberty, gonadotrophin releasing hormone(GnRH) agonists(GnRHa) appear to increase final height if treated early stage. Further large scaled long-term follow-up study of the effects of GnRHa on final height is needed.

• 한국발생생물학회지:발생과생식
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• 제22권2호
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• pp.119-132
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• 2018

GnRH (gonadotropin-releasing hormone) is a supreme hormone regulating reproductive activity in most animals. The sequences of amino acid and nucleic acid of GnRH reported up to now are examined from the evolutionary framework of Chordata. All identified GnRH are classified into GnRH1, GnRH2, or GnRH3. In all three forms of GnRH both N-terminal and C-terminal are conserved, which allows for effective binding to their receptors. The three amino acids in the middle of GnRH1 sequence have altered diversely from the primitive Chordata, which is indicative of the adaptation process to the ambient environment. GnRH2 and GnRH3 sequences are well conserved. There are more diverse modifications in the nucleic acids than in amino acid sequence of GnRH1. These variations can result from meiosis, mutation, or epigenetics and indicate that GnRH is the product of natural selection.