• Restorative Dentistry and Endodontics
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• 제9권1호
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• pp.101-106
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• 1983

It was the purpose of this study to investigate the fracture mode of dental amalgam by observing the crack propagation, and to relate this to the microstructure of the amalgam. Caulk 20th Century Regular, Caulk Spherical, Dispersalloy, and Tytin amalgam alloys were used for this study. After each amalgam alloy and Hg measured exactly by the balance was triturated by the mechanical amalgamator (Capmaster, S.S. White), the triturated mass was inserted into the cylindrical metal mold which was 4 mm in diameter and 12 mm in height and was pressed by the Instron Universal Testing Machine at the speed of 1mm/min with 120Kg. The specimen removed from the mold was stored in the room temperature for a week. This specimen was polished with the emery papers from #100 to #200 and finally on the polishing cloth with 0.06${\mu}Al_2O_3$ powder suspended in water. The specimen was placed on the Instron testing machine in the method similar to the diametral tensile test and loaded at the crosshead speed of 0.05mm/min. The load was stopped short of fracture. The cracks on the polished surface of specimen was examined with scanning electron microscope (JSM-35) and analyzed by EPMA (Electron probe microanalyzer). The following results were obtained. 1. In low copper lathe-cut amalgam, the crack went through the voids and ${\gamma}_2$ phase, through the ${\gamma}_1$ phase around the ${\gamma}$ particles. 2. In low copper spherical amalgam, it was observed that the crack passed through the ${\gamma}_2$ and ${\gamma}_1$ phase, and through the boundary between the ${\gamma}_1$ and ${\gamma}$ phase. 3. In high copper dispersant (Dispersalloy) amalgam, the crack was found to propagate at the interface between the ${\gamma}_1$ matrix and reaction ring around the dispersant (Ag-Cu) particles, and to pass through the Ag-Sn particles. 4. In high copper single composition (Tytin) amalgam, the crack went through the ${\gamma}_1$ matrix between ${\eta}$ crystals, and through the unreacted alloy particle (core).

• 대한전자공학회논문지TC
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• 제47권11호
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• pp.69-76
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• 2010

본 논문에서는 X-Band 모노펄스 레이더 RF 프론트 엔드에서 국부발진 신호를 동일 진폭, 동일 위상으로 분배하는 도파관 천이 구조를 갖는 4-Way 윌킨슨 분배기 설계에 대해 연구하였다. X-Band에서 동작하는 모노펄스 레이더 프론트 엔드는 합, 방위각 및 고각 신호를 하강변환 하는 3개의 도파관 수신믹서와 체계 연동시 X-Band 시험신호를 발생하는 SSB 도파관 믹서로 구성된다. 프론트 엔드를 구성하는 각 믹서에 국부발진(LO : Local oscillator) 신호를 입력하기 위해서는 저 손실 특성을 가지면서 동일 전력 레벨과 동 위상으로 LO 전력을 분배하는 4-Way 분배기가 요구된다. 본 논문에서는 저 손실, 동위상으로 LO 신호를 분배하기 위해 도파관 천이 구조를 갖는 4-Way 윌킨슨 분배기를 설계/제작 하였다. 제작된 윌킨슨 전력 분배기는 X-Band에서 삽입손실이 평균 6.8dB, VSWR은 1.06~1.28였으며, 이때 각 단자 출력 위상차는 최대 4.5도 이내를 유지하였다.

• 한국관광식음료학회지:관광식음료경영연구
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• 제7권
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• pp.61-85
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• 1997

1. Background of the Study Old Testament time made some food and Sauces. Cosher food is God's Covernant. Ancient Greek cooking and Roman cooking had been Sauces. Much of what we know of Greek gastronomy is found in the writting of Archestrate, cooking is sigle and direct, Sauces are Cumin, Vinegar, Roman culinary comes from mareus, first century A.D. many of the ingredients used in apicius's recipes are seen againg in midival Eurpean cooking. ① Cumin Sauce for Oyster ② Sauce for grounds, puree, and cardoons. 2. Culinary in the Middle ages Liaquid Flavorings their Sauces tested Verjuice and Vinegar are most often called for when a Liquid is needed, Spices and Liaisons. 3. Cookery the eighteenth century The eighteen the century brought about greated Systemization of basics, coulis, Jus, and bouillons. 4. The twentieth century culinary Careme were Systematized and recorded by Auguste Escoffier in his Guide Culinare Standardized. 5. Grand Sauces are Considered one of the greatest test of a Chef's Skill, Whether they are classics, Such as Sauce, Supreme, demand the highest technical expertise. The Successful paring of Sauce with a good demonstrates an understanding of the food and an ability to judge. Sauce making allows the cook more freedom to work flavors, textures, Aromatics, Tasty, and color than any other area of cooking. A Sauce is never eaten alone, function, balance, the direct flavor, Sauces presents the basic Sauce-making techniques that have been used in the past and that are popular today, Sauces are organized around the primeifhes of classic world cooking 6. Grand Sauces are 1) Brown Sauces are 1) Brown Sauce ① Demiglace ②Espagnole ③ Fond de veau 2) Bechamel Sauce 3) Velote Sauce 4) Tomato Sauce and 5) Hollandaise Sauce ① Brown Sauce made with Stock, Roux, Tomato Paste and Mirepoix. ② Bechamel Sauce made with Roux and Milk. ③ Veloute Sauce made with Roux and White Stock. ④ Tomato Sauce made with Tomto, Vegetable and Stock. ⑤ Hollandaise Sauce made with Egg and Butter.

• 한국산학기술학회논문지
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• 제14권2호
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• pp.517-522
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• 2013

아이스크림제조기는 원액통과 냉각통의 증발온도가 $4^{\circ}C$와 $-8^{\circ}C$로 각각 다르므로 다수의 모세관을 이용하는데 이 경우 서로 냉매 유량에 영향을 주므로 냉동사이클 설계가 복잡하다. 본 연구에서는 증발온도가 서로 다른 두개의 증발기(냉장 및 냉동)가 장착된 소프트 아이스크림 제조기의 성능을 해석하였다. 압축기 해석에는 효율모델을 적용하였고, 모세관은 1차원 유동으로 간주하여 해석하였으며, 응축기와 증발기는 UA-LMTD법을 적용하여 해석하였다. 요소부품에서의 엔탈피, 압력 및 질량의 평형을 적용하여 냉동사이클 시뮬레이션 프로그램을 개발하였고 R404A를 사용하는 아이스크림 제조기에 적용한 결과, 냉장과 냉동 증발기의 온도를 $3^{\circ}C$ 이내로 예측하여 측정치와 대체로 일치하였다.

• 한국산학기술학회논문지
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• 제21권11호
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• pp.326-333
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• 2020

본 연구는 맞벌이 부부의 결혼만족에 대한 이해를 위해 부부 각각의 성역할 태도, 다중역할 수행에서의 갈등과 향상의 경험이 자신과 배우자에게 미치는 상호영향을 살펴보았다. 이를 위해 맞벌이 부부 95쌍, 총 190명을 대상으로 하여 대응표본 t검증과 중다회귀분석을 실시하였다. 먼저 맞벌이 부부의 성역할태도, 다중역할 경험 및 결혼만족도에 있어 부부 간 차이를 살펴본 결과, 성역할태도 및 다중역할 경험에 있어 부부 간의 유의한 차이는 없었으며, 결혼만족도에 있어 남편이 아내보다 유의하게 만족하는 것으로 나타났다. 둘째, 맞벌이 부부의 결혼만족도에 영향을 미치는 요인에 대한 상호영향을 살펴본 결과, 부부 간의 결혼만족도에 영향을 주는 변인에서 유의한 차이가 발견되었다. 남편의 경우 자신의 성역할태도, 자신의 다중역할 향상이 결혼생활의 만족도에 정적으로 유의한 영향을 주는 반면, 아내의 경우는 남편의 성역할태도가 결혼생활 만족에 있어 정적으로 영향을 미치며 아내 자신의 다중역할 갈등이 결혼생활의 만족도에 부적인 영향을 미치는 것으로 나타났다. 이는 맞벌이 부부의 결혼만족에 관한 교육 및 프로그램에 있어 남편과 아내 각각의 영향과 상호간의 영향에 대한 고려가 필요함을 시사한다.

• 대한물리의학회지
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• 제14권4호
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• pp.45-53
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• 2019

PURPOSE: This study examined the differences in the trunk impairment scores according to the levels of the gross motor classification system by evaluating trunk control in children with spastic cerebral palsy using the index of trunk impairment. In addition, the characteristics of trunk control disabilities were investigated according to the cerebral palsy type. METHODS: The subjects were 49 children (mean age 8.57±1.83 years, 11 with hemiplegia, 26 with diplegia, and 12 with quadriplegia) with spastic cerebral palsy levels I to IV under the gross motor function classification system (GMFCS). The coordination and balance of the children with cerebral palsy were evaluated using the index for trunk impairment. Statistical analyses were performed using a Kruskal-Wallis test, and Bonferroni analyses were used as a post-hoc comparison for any significant results. RESULTS: The median of the total scores of trunk impairment was 13 (range, 9-17), which was 56% of the maximum score. The total score of trunk impairment and subscales differed significantly according to the disease severity and type of motor disability. The scores for children with quadriplegia were the lowest compared to children with hemiplegia and diplegia. CONCLUSION: Trunk control function in children with spastic cerebral palsy was reduced, and varied according to the disease severity and types of motor disabilities. The degree of trunk impairment differed from the trunk control ability according to the degree of motor disability of children with cerebral palsy.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.361-364
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• 2009

KEPRI has studied planar type SOFC stacks using anode-supported single cells and kW class co-generation systems for residential power generation. A 1kW class SOFC system consisted of a hot box part, a cold BOP part and a water reservoir. A hot box part contains a SOFC stack made up of 48 cells with $10{\times}10cm^2$ area and ferritic stainless steel interconnectors, a fuel reformer, a catalytic combustor and heat exchangers. Thermal management and insulation system were especially designed for self-sustainable operation. A cold BOP part was composed of blowers, pumps, a water trap and system control units. When a 1kW class SOFC system was operated at $750^{\circ}C$ with hydrogen, the stack power was 1.2kW at 30 A and 1.6kW at 50A. Turning off an electric furnace, the SOFC system was operated using hydrogen and city gas without any external heat source. Under self-sustainable operation conditions, the stack power was about 1.3kW with hydrogen and 1.2kW with city gas respectively. The system also recuperated heat of about 1.1kW by making hot water. Recently KEPRI developed stacks using $15{\times}15cm^2$ cells and tested them. KEPRI will develop a 5 kW class CHP system using $15{\times}15cm^2$ stacks by 2010.

• 대한물리치료과학회지
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• 제26권3호
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• pp.1-7
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• 2019

Purpose: The purpose of this study was to investigate the effects of the Otago exercise combined with action observation training on changes of the brain activity of the elderly. Design: Randomized controlled trial. Methods: Thirty elderly women in the experiment were included. Participants were randomly assigned to the Otago combined with action observation training group, the Otago exercise group, and the control group (10 in each group). The Otago combined with action observation training group and the Otago exercise group performed the strength and balance exercises of the Otago exercise program for 50 minutes three times a week for 12 weeks. The Otago combined with action observation training group underwent additional action observation training for the Otago movement for 20 minutes three times a week. No intervention was performed in the control group. PolyG-1 (LAXTHA Inc., Daejeon, Korea) was used to measure the changes in the brain activity following intervention. One-way analysis of variance was used to compare the effects among the groups and a post-hoc test was performed. Results: The relative mu rhythms in the F3, C3, and C4 regions were significantly increased in the Otago combined with action observation training group. Relative beta wave activity in the Fp1, F3, F3, and C3 regions was significantly increased in the Otago combined with action observation training group (p<0.05). Conclusion: The results indicated that the Otago exercise combined with action observation training was effective for promoting the brain activity of the elderly.

• 한국자동차공학회논문집
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• 제21권3호
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• pp.82-87
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• 2013

In this work, the 1L grade integrated metal DOC/DPF filter that can install in engine manifold position was developed to investigate the effect of platinum-coating amount of filter on the improvement of filter activation temperature and reduction of particulate matter (PM). This filter was installed in 2.9L CI engine which meets the EURO-4 emission regulation. Tests for PM reduction efficiency of filter were conducted under ND-13 mode with full-load test condition. It was revealed that the time to reach the activation temperature of metal filter ($280^{\circ}C$) was shorter as the amount of platinum-coating increased. This short activation time can be helpful for the reduction of CO and HC emissions during cold start condition. At the same time, PM reduced as the coating amount increased. The reduction percentage of $DOC_{40}$, $DOC_{20}$, and $DOC_0$ were 96.7% (2.34 mg/kW'h), 95.1% (3.47 mg/kW'h), and 94.5% (3.69 mg/kW'h) compared to previous result (71.4 mg/kW'h), respectively.

• Asian Pacific Journal of Cancer Prevention
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• 제15권3호
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• pp.1307-1312
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• 2014

Background: The objective of this study was to examine the effect of self-concept levels and perceived academic achievements of sixth, seventh and eighth grade primary school students upon their perceptions about smoking. Method: The data were collected with the Socio-Demographic Data Collection Form, Pier-Herris Self-Concept scale and Children's Decision Balance Scale. The study sample consisted of 374 students receiving education in the sixth, seventh and eighth grades of three primary schools, which were selected among primary schools of Izmir Provincial Directorate for National Education representing three socio-economic groups with a simple random sampling method. The data were collected in December 2012-January 2013. Percentages and the t test were used in the evaluation of the data. Results: While students with a positive self-concept had score averages of $7.12{\pm}2.18$ regarding the lower dimension of smoking pros and $29.0{\pm}2.47$ regarding the lower dimension of smoking cons, their counterparts with a negative self-concept had score averages of $8.61{\pm}3.76$ (p=0.000) and $28.1{\pm}3.49$ (p=0.004), respectively. According to self-perception, there was statistical difference between perceptions of students regarding smoking (p<0.01). While students perceiving themselves successful had score averages of $7.81{\pm}3.13$ and $28.5{\pm}3.19$ regarding the lower dimension of smoking benefit and harm, students perceiving themselves unsuccessful had score averages of $8.27{\pm}3.39$ (p=0.333) and $29.01{\pm}2.05$ (p=0.235), with no difference determined. Conclusion: Students with a positive self-perception had a low perception of smoking pros and a high perception of smoking cons. Perception of academic achievement did not affect the pros and cons perceptions of children regarding smoking.